diff --git a/thys/IEEE_Floating_Point/Conversion_IEEE_Float.thy b/thys/IEEE_Floating_Point/Conversion_IEEE_Float.thy
--- a/thys/IEEE_Floating_Point/Conversion_IEEE_Float.thy
+++ b/thys/IEEE_Floating_Point/Conversion_IEEE_Float.thy
@@ -1,346 +1,346 @@
 (* Author: Fabian Hellauer
            Fabian Immler
 *)
 theory Conversion_IEEE_Float
   imports
     "HOL-Library.Float"
     IEEE_Properties
     "HOL-Library.Code_Target_Numeral"
 begin
 
 definition "of_finite (x::('e, 'f)float) =
   (if is_normal x then (Float (normal_mantissa x) (normal_exponent x))
     else if is_denormal x then (Float (denormal_mantissa x) (denormal_exponent TYPE(('e, 'f)float)))
     else 0)"
 
 lemma float_val_of_finite: "is_finite x \<Longrightarrow> of_finite x = valof x"
   by (induction x) (auto simp: normal_imp_not_denormal of_finite_def)
 
 definition is_normal_Float::"('e, 'f)float itself \<Rightarrow> Float.float \<Rightarrow> bool" where
   "is_normal_Float x f \<longleftrightarrow>
     mantissa f \<noteq> 0 \<and>
     bitlen \<bar>mantissa f\<bar> \<le> fracwidth x + 1 \<and>
     - int (bias x) - bitlen \<bar>mantissa f\<bar> + 1 < Float.exponent f \<and>
     Float.exponent f < 2^(LENGTH('e)) - bitlen \<bar>mantissa f\<bar> - bias x"
 
 definition is_denormal_Float::"('e, 'f)float itself \<Rightarrow> Float.float \<Rightarrow> bool" where
   "is_denormal_Float x f \<longleftrightarrow>
     mantissa f \<noteq> 0 \<and>
     bitlen \<bar>mantissa f\<bar> \<le> 1 - Float.exponent f - int (bias x) \<and>
     1 - 2^(LENGTH('e) - 1) - int LENGTH('f) < Float.exponent f"
 
 lemmas is_denormal_FloatD =
   is_denormal_Float_def[THEN iffD1, THEN conjunct1]
   is_denormal_Float_def[THEN iffD1, THEN conjunct2]
 
 definition is_finite_Float::"('e, 'f)float itself \<Rightarrow> Float.float \<Rightarrow> bool" where
   "is_finite_Float x f \<longleftrightarrow> is_normal_Float x f \<or> is_denormal_Float x f \<or> f = 0"
 
 lemma is_finite_Float_eq:
   "is_finite_Float TYPE(('e, 'f)float) f \<longleftrightarrow>
     (let e = Float.exponent f; bm = bitlen (abs (mantissa f))
     in bm \<le> Suc LENGTH('f) \<and>
      bm \<le> 2 ^ (LENGTH('e) - 1) - e \<and>
      1 - 2 ^ (LENGTH('e) - 1) - int LENGTH('f) < e)"
 proof -
   have *: "(2::int) ^ (LENGTH('e) - Suc 0) - 1 < 2 ^ LENGTH('e)"
     by (metis Suc_1 diff_le_self lessI linorder_not_less one_less_numeral_iff
         power_strict_increasing_iff zle_diff1_eq)
   have **: "1 - 2 ^ (LENGTH('e) - Suc 0) < int LENGTH('f)"
     by (smt len_gt_0 of_nat_0_less_iff zero_less_power)
   have ***: "2 ^ (LENGTH('e) - 1) + 1 =
     2 ^ LENGTH('e) - int (bias TYPE(('e, 'f) IEEE.float))"
-    by (simp add: bias_def power_Suc[symmetric] of_nat_diff)
+    by (simp add: bias_def power_Suc[symmetric] of_nat_diff mask_eq_exp_minus_1)
   have rewr: "x \<le> 2 ^ n - e \<longleftrightarrow> x + e < 2 ^ n + 1" for x::int and n e
     by auto
   show ?thesis
     unfolding *** rewr
     using * **
     unfolding is_finite_Float_def is_normal_Float_def is_denormal_Float_def
-    by (auto simp: Let_def bias_def mantissa_eq_zero_iff of_nat_diff
+    by (auto simp: Let_def bias_def mantissa_eq_zero_iff of_nat_diff mask_eq_exp_minus_1
         intro: le_less_trans[OF add_right_mono])
 qed
 
 lift_definition normal_of_Float :: "Float.float \<Rightarrow> ('e, 'f)float"
   is "\<lambda>x. let m = mantissa x; e = Float.exponent x in
     (if m > 0 then 0 else 1,
       word_of_int (e + int (bias TYPE(('e, 'f)float)) + bitlen \<bar>m\<bar> - 1),
       word_of_int (\<bar>m\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>m\<bar>)) - 2 ^ (LENGTH('f))))"
   .
 
 lemma sign_normal_of_Float:"sign (normal_of_Float x) = (if x > 0 then 0 else 1)"
   by transfer (auto simp: Let_def mantissa_pos_iff)
 
 lemma uint_word_of_int_bitlen_eq:
   "uint (word_of_int x::'a::len word) = x" if "bitlen x \<le> LENGTH('a)" "x \<ge> 0"
   using that by (simp add: bitlen_le_iff_power take_bit_int_eq_self unsigned_of_int)
 
 lemma fraction_normal_of_Float:"fraction (normal_of_Float x::('e, 'f)float) =
   (nat \<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>)) - 2 ^ LENGTH('f))"
   if "is_normal_Float TYPE(('e, 'f)float) x"
 proof -
   from that have bmp: "bitlen \<bar>mantissa x\<bar> > 0"
     by (metis abs_of_nonneg bitlen_bounds bitlen_def is_normal_Float_def nat_code(2) of_nat_0_le_iff
         power.simps(1) zabs_less_one_iff zero_less_abs_iff)
   have mless: "\<bar>mantissa x\<bar> < 2 ^ nat (bitlen \<bar>mantissa x\<bar>)"
     using bitlen_bounds by force
   have lem: "2 ^ nat (bitlen \<bar>mantissa x\<bar> - 1) \<le> \<bar>mantissa x\<bar>"
     using bitlen_bounds is_normal_Float_def that zero_less_abs_iff by blast
   from that have nble: "nat (bitlen \<bar>mantissa x\<bar>) \<le> Suc LENGTH('f)"
     using bitlen_bounds by (auto simp: is_normal_Float_def)
   have nn: "0 \<le> \<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>)) - 2 ^ LENGTH('f)"
     apply (rule add_le_imp_le_diff)
     apply (rule order_trans[rotated])
      apply (rule mult_right_mono)
       apply (rule lem, force)
     unfolding power_add[symmetric]
     using nble bmp
     by (auto)
   have "\<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>)) < 2 * 2 ^ LENGTH('f)"
     apply (rule less_le_trans)
      apply (rule mult_strict_right_mono)
       apply (rule mless)
      apply force
     unfolding power_add[symmetric] power_Suc[symmetric]
     apply (rule power_increasing)
     using nble
     by auto
   then have "bitlen (\<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>)) - 2 ^ LENGTH('f))
     \<le> int LENGTH('f)"
     unfolding bitlen_le_iff_power
     by simp
   then show ?thesis
     apply (transfer fixing: x)
     unfolding Let_def split_beta' fst_conv snd_conv uint_nat [symmetric] nat_uint_eq [symmetric]
     using nn
     apply (subst uint_word_of_int_bitlen_eq)
       apply (auto simp: nat_mult_distrib nat_diff_distrib nat_power_eq)
     done
 qed
 
 lemma exponent_normal_of_Float:"exponent (normal_of_Float x::('e, 'f)float) =
   nat (Float.exponent x + (bias TYPE(('e, 'f)float)) + bitlen \<bar>mantissa x\<bar> - 1)"
   if "is_normal_Float TYPE(('e, 'f)float) x"
   using that
   apply (transfer fixing: x)
   apply (simp flip: uint_nat nat_uint_eq add: Let_def)
   apply (auto simp: is_normal_Float_def bitlen_le_iff_power uint_word_of_int_bitlen_eq Let_def)
   apply transfer
   apply (simp add: nat_take_bit_eq take_bit_int_eq_self)
   done
 
 lift_definition denormal_of_Float :: "Float.float \<Rightarrow> ('e, 'f)float"
   is "\<lambda>x. let m = mantissa x; e = Float.exponent x in
   (if m \<ge> 0 then 0 else 1, 0,
     word_of_int (\<bar>m\<bar> * 2 ^ nat (e + bias TYPE(('e, 'f)float) + fracwidth TYPE(('e, 'f)float) - 1)))"
   .
 
 lemma sign_denormal_of_Float:"sign (denormal_of_Float x) = (if x \<ge> 0 then 0 else 1)"
   by transfer (auto simp: Let_def mantissa_nonneg_iff)
 
 lemma exponent_denormal_of_Float:"exponent (denormal_of_Float x::('e, 'f)float) = 0"
   by (transfer fixing: x) (auto simp: Let_def)
 
 lemma fraction_denormal_of_Float:"fraction (denormal_of_Float x::('e, 'f)float) =
   (nat \<bar>mantissa x\<bar> * 2 ^ nat (Float.exponent x + bias TYPE(('e, 'f)float) + LENGTH('f) - 1))"
   if "is_denormal_Float TYPE(('e, 'f)float) x"
 proof -
   have mless: "\<bar>mantissa x\<bar> < 2 ^ nat (bitlen \<bar>mantissa x\<bar>)"
     using bitlen_bounds by force
   have *: "nat (bitlen \<bar>mantissa x\<bar>) +
     nat (Float.exponent x + (2 ^ (LENGTH('e) - Suc 0) + int LENGTH('f)) - 2)
     \<le> LENGTH('f)"
     using that
-    by (auto simp: is_denormal_Float_def nat_diff_distrib' le_diff_conv
+    by (auto simp: is_denormal_Float_def nat_diff_distrib' le_diff_conv mask_eq_exp_minus_1
         bitlen_nonneg nat_le_iff bias_def nat_add_distrib[symmetric] of_nat_diff)
   have "\<bar>mantissa x\<bar> *  2 ^ nat (Float.exponent x + int (bias TYPE(('e, 'f)float)) +
     LENGTH('f) - 1) < 2 ^ LENGTH('f)"
     apply (rule less_le_trans)
      apply (rule mult_strict_right_mono)
       apply (rule mless, force)
     unfolding power_add[symmetric] power_Suc[symmetric]
     apply (rule power_increasing)
      apply (auto simp: bias_def)
     using that *
-    by (auto simp: is_denormal_Float_def algebra_simps of_nat_diff)
+    by (auto simp: is_denormal_Float_def algebra_simps of_nat_diff mask_eq_exp_minus_1)
   then show ?thesis
     apply (transfer fixing: x)
     apply transfer
     apply (simp add: Let_def nat_eq_iff take_bit_eq_mod)
     done
 qed
 
 definition of_finite_Float :: "Float.float \<Rightarrow> ('e, 'f) float" where
   "of_finite_Float x = (if is_normal_Float TYPE(('e, 'f)float) x then normal_of_Float x
     else if is_denormal_Float TYPE(('e, 'f)float) x then denormal_of_Float x
     else 0)"
 
 lemma valof_normal_of_Float: "valof (normal_of_Float x::('e, 'f)float) = x"
   if "is_normal_Float TYPE(('e, 'f)float) x"
 proof -
   have "valof (normal_of_Float x::('e, 'f)float) =
     (- 1) ^ sign (normal_of_Float x::('e, 'f)float) *
     ((1 + real (nat \<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>)) - 2 ^ LENGTH('f)) / 2 ^ LENGTH('f)) *
       2 powr (bitlen \<bar>mantissa x\<bar> - 1)) *
     2 powr Float.exponent x"
     (is "_ = ?s * ?m * ?e")
     using that
     by (auto simp: is_normal_Float_def valof_eq fraction_normal_of_Float
         powr_realpow[symmetric] exponent_normal_of_Float powr_diff powr_add)
   also
   have "\<bar>mantissa x\<bar> > 0"
     using that
     by (auto simp: is_normal_Float_def)
   have bound: "2 ^ LENGTH('f) \<le> nat \<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>))"
   proof -
     have "(2::nat) ^ LENGTH('f) \<le> 2 ^ nat (bitlen \<bar>mantissa x\<bar> - 1) * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>))"
       by (simp add: power_add[symmetric])
     also have "\<dots> \<le> nat \<bar>mantissa x\<bar> * 2 ^ (Suc LENGTH('f) - nat (bitlen \<bar>mantissa x\<bar>))"
       using bitlen_bounds[of "\<bar>mantissa x\<bar>"] that
       by (auto simp: is_normal_Float_def)
     finally show ?thesis .
   qed
   have "?m = abs (mantissa x)"
     apply (subst of_nat_diff)
     subgoal using bound by auto
     subgoal
       using that
       by (auto simp: powr_realpow[symmetric] powr_add[symmetric]
           is_normal_Float_def bitlen_nonneg of_nat_diff divide_simps)
     done
   finally show ?thesis
     by (auto simp: mantissa_exponent sign_normal_of_Float abs_real_def zero_less_mult_iff)
 qed
 
 lemma valof_denormal_of_Float: "valof (denormal_of_Float x::('e, 'f)float) = x"
   if "is_denormal_Float TYPE(('e, 'f)float) x"
 proof -
   have less: "0 < Float.exponent x + (int (bias TYPE(('e, 'f) IEEE.float)) + int LENGTH('f))"
     using that
-    by (auto simp: is_denormal_Float_def bias_def of_nat_diff)
+    by (auto simp: is_denormal_Float_def bias_def of_nat_diff mask_eq_exp_minus_1)
   have "valof (denormal_of_Float x::('e, 'f)float) =
     ((- 1) ^ sign (denormal_of_Float x::('e, 'f)float) * \<bar>real_of_int (mantissa x)\<bar>) *
     (2 powr real (nat (Float.exponent x + int (bias TYPE(('e, 'f) IEEE.float)) + int LENGTH('f) - 1)) /
       (2 powr real (bias TYPE(('e, 'f) IEEE.float)) * 2 powr LENGTH('f)) * 2)"
     (is "_ = ?m * ?e")
     by (auto simp: valof_eq exponent_denormal_of_Float fraction_denormal_of_Float that
         mantissa_exponent powr_realpow[symmetric])
   also have "?m = mantissa x"
     by (auto simp: sign_denormal_of_Float abs_real_def mantissa_neg_iff)
   also have "?e = 2 powr Float.exponent x"
     by (auto simp: powr_add[symmetric] divide_simps powr_mult_base less ac_simps)
   finally show ?thesis by (simp add: mantissa_exponent)
 qed
 
 lemma valof_of_finite_Float:
   "is_finite_Float (TYPE(('e, 'f) IEEE.float)) x \<Longrightarrow> valof (of_finite_Float x::('e, 'f)float) = x"
   by (auto simp: of_finite_Float_def is_finite_Float_def valof_denormal_of_Float valof_normal_of_Float)
 
 lemma is_normal_normal_of_Float:
   "is_normal (normal_of_Float x::('e, 'f)float)" if "is_normal_Float TYPE(('e, 'f)float) x"
   using that
   by (auto simp: is_normal_def exponent_normal_of_Float that is_normal_Float_def
       emax_eq nat_less_iff of_nat_diff)
 
 lemma is_denormal_denormal_of_Float: "is_denormal (denormal_of_Float x::('e, 'f)float)"
   if "is_denormal_Float TYPE(('e, 'f)float) x"
   using that
   by (auto simp: is_denormal_def exponent_denormal_of_Float that is_denormal_Float_def
       emax_eq fraction_denormal_of_Float le_nat_iff bias_def)
 
 lemma is_finite_of_finite_Float: "is_finite (of_finite_Float x)"
   by (auto simp: is_finite_def of_finite_Float_def is_normal_normal_of_Float
       is_denormal_denormal_of_Float)
 
 lemma Float_eq_zero_iff: "Float m e = 0 \<longleftrightarrow> m = 0"
   by (metis Float.compute_is_float_zero Float_0_eq_0)
 
 lemma bitlen_mantissa_Float:
   shows "bitlen \<bar>mantissa (Float m e)\<bar> = (if m = 0 then 0 else bitlen \<bar>m\<bar> + e) - Float.exponent (Float m e)"
   using bitlen_Float[of m e] by auto
 
 lemma exponent_Float:
   shows "Float.exponent (Float m e) = (if m = 0 then 0 else bitlen \<bar>m\<bar> + e) - bitlen \<bar>mantissa (Float m e)\<bar> "
   using bitlen_Float[of m e] by auto
 
 lemma is_normal_Float_normal:
   "is_normal_Float TYPE(('e, 'f)float) (Float (normal_mantissa x) (normal_exponent x))"
   if "is_normal x" for x::"('e, 'f)float"
 proof -
   define f where "f = Float (normal_mantissa x) (normal_exponent x)"
   from that have "f \<noteq> 0"
     by (auto simp: f_def is_normal_def zero_float_def[symmetric]
         Float_eq_zero_iff normal_mantissa_def add_nonneg_eq_0_iff)
   from denormalize_shift[OF f_def this] obtain i where
     i: "normal_mantissa x = mantissa f * 2 ^ i" "normal_exponent x = Float.exponent f - int i"
     by auto
   have "mantissa f \<noteq> 0"
     by (auto simp: \<open>f \<noteq> 0\<close> i mantissa_eq_zero_iff Float_eq_zero_iff)
   moreover
   have "normal_exponent x \<le> Float.exponent f" unfolding i by simp
   then have " bitlen \<bar>mantissa f\<bar> \<le> 1 + int LENGTH('f)"
     unfolding bitlen_mantissa_Float bitlen_normal_mantissa f_def
     by auto
   moreover
   have "- int (bias TYPE(('e, 'f)float)) - bitlen \<bar>mantissa f\<bar> + 1 < Float.exponent f"
     unfolding bitlen_mantissa_Float bitlen_normal_mantissa f_def
     using that
     by (auto simp: mantissa_eq_zero_iff abs_mult bias_def normal_mantissa_def normal_exponent_def
         is_normal_def emax_eq less_diff_conv add_nonneg_eq_0_iff)
   moreover
   have "2 ^ (LENGTH('e) - Suc 0) + - (1::int) * 2 ^ LENGTH('e) \<le> 0"
     by simp
   then have "(2::int) ^ (LENGTH('e) - Suc 0) < 1 + 2 ^ LENGTH('e)" by arith
   then have "Float.exponent f <
       2 ^ LENGTH('e) - bitlen \<bar>mantissa f\<bar> - int (bias TYPE(('e, 'f)float))"
     using normal_exponent_bounds_int[OF that]
     unfolding bitlen_mantissa_Float bitlen_normal_mantissa f_def
-    by (auto simp: bias_def algebra_simps power_Suc[symmetric] of_nat_diff
+    by (auto simp: bias_def algebra_simps power_Suc[symmetric] of_nat_diff mask_eq_exp_minus_1
         intro: le_less_trans[OF add_right_mono] normal_exponent_bounds_int[OF that])
   ultimately
   show ?thesis
     by (auto simp: is_normal_Float_def f_def)
 qed
 
 
 lemma is_denormal_Float_denormal:
   "is_denormal_Float TYPE(('e, 'f)float)
     (Float (denormal_mantissa x) (denormal_exponent TYPE(('e, 'f)float)))"
   if "is_denormal x" for x::"('e, 'f)float"
 proof -
   define f where "f = Float (denormal_mantissa x) (denormal_exponent TYPE(('e, 'f)float))"
   from that have "f \<noteq> 0"
     by (auto simp: f_def is_denormal_def zero_float_def[symmetric]
         Float_eq_zero_iff denormal_mantissa_def add_nonneg_eq_0_iff)
   from denormalize_shift[OF f_def this] obtain i where
     i: "denormal_mantissa x = mantissa f * 2 ^ i" "denormal_exponent TYPE(('e, 'f)float) = Float.exponent f - int i"
     by auto
   have "mantissa f \<noteq> 0"
     by (auto simp: \<open>f \<noteq> 0\<close> i mantissa_eq_zero_iff Float_eq_zero_iff)
   moreover
   have "bitlen \<bar>mantissa f\<bar> \<le> 1 - Float.exponent f - int (bias TYPE(('e, 'f) IEEE.float))"
     using \<open>mantissa f \<noteq> 0\<close>
     unfolding f_def bitlen_mantissa_Float
     using bitlen_denormal_mantissa[of x]
     by (auto simp: denormal_exponent_def)
   moreover
   have "2 - 2 ^ (LENGTH('e) - Suc 0) - int LENGTH('f) \<le> Float.exponent f"
     (is "?l \<le> _")
   proof -
     have "?l \<le> denormal_exponent TYPE(('e, 'f)float) + i"
       using that
-      by (auto simp: is_denormal_def bias_def denormal_exponent_def of_nat_diff)
+      by (auto simp: is_denormal_def bias_def denormal_exponent_def of_nat_diff mask_eq_exp_minus_1)
     also have "\<dots> = Float.exponent f" unfolding i by auto
     finally show ?thesis .
   qed
   ultimately
   show ?thesis
     unfolding is_denormal_Float_def exponent_Float f_def[symmetric]
     by auto
 qed
 
 lemma is_finite_Float_of_finite: "is_finite_Float TYPE(('e, 'f)float) (of_finite x)" for x::"('e, 'f)float"
   by (auto simp: is_finite_Float_def of_finite_def is_normal_Float_normal
       is_denormal_Float_denormal)
 
 end
diff --git a/thys/IEEE_Floating_Point/IEEE_Properties.thy b/thys/IEEE_Floating_Point/IEEE_Properties.thy
--- a/thys/IEEE_Floating_Point/IEEE_Properties.thy
+++ b/thys/IEEE_Floating_Point/IEEE_Properties.thy
@@ -1,1022 +1,1026 @@
 (* Author: Lei Yu, University of Cambridge
    Author: Fabian Hellauer
            Fabian Immler
 *)
 
 section \<open>Proofs of Properties about Floating Point Arithmetic\<close>
 
 theory IEEE_Properties
 imports IEEE
 begin
 
 subsection \<open>Theorems derived from definitions\<close>
 
 
 lemma valof_eq:
   "valof x =
     (if exponent x = 0
        then (- 1) ^ sign x * (2 / 2 ^ bias TYPE(('a, 'b) float)) *
             (real (fraction x) / 2 ^ LENGTH('b))
        else (- 1) ^ sign x * (2 ^ exponent x / 2 ^ bias TYPE(('a, 'b) float)) *
             (1 + real (fraction x) / 2 ^ LENGTH('b)))"
   for x::"('a, 'b) float"
   unfolding Let_def
   by transfer (auto simp: bias_def divide_simps unat_eq_0)
 
-lemma exponent_le[simp]:
-  "exponent a \<le> unat (-1::'a word)" for a::"('a, _)float"
-  by transfer (auto intro!: unat_mono simp: word_le_nat_alt[symmetric])
+lemma exponent_le [simp]:
+  \<open>exponent a \<le> mask LENGTH('a)\<close> for a :: \<open>('a, _) float\<close>
+  by transfer (auto simp add: of_nat_mask_eq intro: word_unat_less_le split: prod.split)
 
-lemma
-  max_word_le_exponent_iff[simp]:
-  "unat (- 1::'a word) \<le> exponent a \<longleftrightarrow> unat (- 1::'a word) = exponent a"
-  for a::"('a, _)float"
-  using le_antisym by fastforce
+lemma exponent_not_less [simp]:
+  \<open>\<not> mask LENGTH('a) < IEEE.exponent a\<close> for a :: \<open>('a, _) float\<close>
+  by (simp add: not_less)
 
 lemma infinity_simps:
   "sign (plus_infinity::('e, 'f)float) = 0"
   "sign (minus_infinity::('e, 'f)float) = 1"
   "exponent (plus_infinity::('e, 'f)float) = emax TYPE(('e, 'f)float)"
   "exponent (minus_infinity::('e, 'f)float) = emax TYPE(('e, 'f)float)"
   "fraction (plus_infinity::('e, 'f)float) = 0"
   "fraction (minus_infinity::('e, 'f)float) = 0"
   subgoal by transfer auto
   subgoal by transfer auto
-  subgoal by transfer (auto simp: emax_def)
-  subgoal by transfer (auto simp: emax_def)
+  subgoal by transfer (simp add: emax_def mask_eq_exp_minus_1)
+  subgoal by transfer (simp add: emax_def mask_eq_exp_minus_1)
   subgoal by transfer auto
   subgoal by transfer auto
   done
 
 lemma zero_simps:
   "sign (0::('e, 'f)float) = 0"
   "sign (- 0::('e, 'f)float) = 1"
   "exponent (0::('e, 'f)float) = 0"
   "exponent (- 0::('e, 'f)float) = 0"
   "fraction (0::('e, 'f)float) = 0"
   "fraction (- 0::('e, 'f)float) = 0"
   subgoal by transfer auto
   subgoal by transfer auto
   subgoal by transfer auto
   subgoal by transfer auto
   subgoal by transfer auto
   subgoal by transfer auto
   done
 
-lemma emax_eq: "emax x = 2^LENGTH('e) - 1"
+lemma emax_eq: "emax x = 2 ^ LENGTH('e) - 1"
   for x::"('e, 'f)float itself"
-  by (simp add: emax_def unat_minus_one_word)
+  by (simp add: emax_def unsigned_minus_1_eq_mask mask_eq_exp_minus_1)
 
 lemma topfloat_simps:
   "sign (topfloat::('e, 'f)float) = 0"
   "exponent (topfloat::('e, 'f)float) = emax TYPE(('e, 'f)float) - 1"
-  "fraction (topfloat::('e, 'f)float) = 2^fracwidth TYPE(('e, 'f)float) - 1"
+  "fraction (topfloat::('e, 'f)float) = 2 ^ (fracwidth TYPE(('e, 'f)float)) - 1"
   and bottomfloat_simps:
   "sign (bottomfloat::('e, 'f)float) = 1"
   "exponent (bottomfloat::('e, 'f)float) = emax TYPE(('e, 'f)float) - 1"
-  "fraction (bottomfloat::('e, 'f)float) = 2^fracwidth TYPE(('e, 'f)float) - 1"
+  "fraction (bottomfloat::('e, 'f)float) = 2 ^ (fracwidth TYPE(('e, 'f)float)) - 1"
   subgoal by transfer simp
-  subgoal by transfer (simp add: emax_eq take_bit_minus_small_eq
-    nat_diff_distrib nat_power_eq)
-  subgoal by transfer (simp add: unat_minus_one_word)
+  subgoal by transfer (simp add: emax_eq take_bit_minus_small_eq nat_diff_distrib nat_power_eq)
+  subgoal by transfer (simp add: unsigned_minus_1_eq_mask mask_eq_exp_minus_1)
   subgoal by transfer simp
-  subgoal by transfer (simp add: emax_eq take_bit_minus_small_eq
-    unat_minus_one_word nat_diff_distrib nat_power_eq)
-  subgoal by transfer (simp add: unat_minus_one_word)
+  subgoal by transfer (simp add: emax_eq take_bit_minus_small_eq nat_diff_distrib nat_power_eq)
+  subgoal by transfer (simp add: unsigned_minus_1_eq_mask mask_eq_exp_minus_1)
   done
 
 lemmas float_defs =
   is_finite_def is_infinity_def is_zero_def is_nan_def
   is_normal_def is_denormal_def valof_eq
   less_eq_float_def less_float_def
   flt_def fgt_def fle_def fge_def feq_def
   fcompare_def
   infinity_simps
   zero_simps
   topfloat_simps
   bottomfloat_simps
   float_eq_def
 
 lemma float_cases: "is_nan a \<or> is_infinity a \<or> is_normal a \<or> is_denormal a \<or> is_zero a"
-  by (auto simp: emax_def float_defs not_less)
+  by (auto simp add: float_defs not_less le_less emax_def unsigned_minus_1_eq_mask)
 
 lemma float_cases_finite: "is_nan a \<or> is_infinity a \<or> is_finite a"
   by (simp add: float_cases is_finite_def)
 
 lemma float_zero1[simp]: "is_zero 0"
   unfolding float_defs
   by transfer auto
 
 lemma float_zero2[simp]: "is_zero (- x) \<longleftrightarrow> is_zero x"
   unfolding float_defs
   by transfer auto
 
 lemma emax_pos[simp]: "0 < emax x" "emax x \<noteq> 0"
   by (auto simp: emax_def)
 
+
 text \<open>The types of floating-point numbers are mutually distinct.\<close>
 lemma float_distinct:
   "\<not> (is_nan a \<and> is_infinity a)"
   "\<not> (is_nan a \<and> is_normal a)"
   "\<not> (is_nan a \<and> is_denormal a)"
   "\<not> (is_nan a \<and> is_zero a)"
   "\<not> (is_infinity a \<and> is_normal a)"
   "\<not> (is_infinity a \<and> is_denormal a)"
   "\<not> (is_infinity a \<and> is_zero a)"
   "\<not> (is_normal a \<and> is_denormal a)"
   "\<not> (is_denormal a \<and> is_zero a)"
   by (auto simp: float_defs)
 
 lemma denormal_imp_not_zero: "is_denormal f \<Longrightarrow> \<not>is_zero f"
   by (simp add: is_denormal_def is_zero_def)
 
 lemma normal_imp_not_zero: "is_normal f \<Longrightarrow> \<not>is_zero f"
   by (simp add: is_normal_def is_zero_def)
 
 lemma normal_imp_not_denormal: "is_normal f \<Longrightarrow> \<not>is_denormal f"
   by (simp add: is_normal_def is_denormal_def)
 
 lemma denormal_zero[simp]: "\<not>is_denormal 0" "\<not>is_denormal minus_zero"
   using denormal_imp_not_zero float_zero1 float_zero2 by blast+
 
 lemma normal_zero[simp]: "\<not>is_normal 0" "\<not>is_normal minus_zero"
   using normal_imp_not_zero float_zero1 float_zero2 by blast+
 
 lemma float_distinct_finite: "\<not> (is_nan a \<and> is_finite a)" "\<not>(is_infinity a \<and> is_finite a)"
   by (auto simp: float_defs)
 
 lemma finite_infinity: "is_finite a \<Longrightarrow> \<not> is_infinity a"
   by (auto simp: float_defs)
 
 lemma finite_nan: "is_finite a \<Longrightarrow> \<not> is_nan a"
   by (auto simp: float_defs)
 
 text \<open>For every real number, the floating-point numbers closest to it always exist.\<close>
 lemma is_closest_exists:
   fixes v :: "('e, 'f)float \<Rightarrow> real"
     and s :: "('e, 'f)float set"
   assumes finite: "finite s"
     and non_empty: "s \<noteq> {}"
   shows "\<exists>a. is_closest v s x a"
   using finite non_empty
 proof (induct s rule: finite_induct)
   case empty
   then show ?case by simp
 next
   case (insert z s)
   show ?case
   proof (cases "s = {}")
     case True
     then have "is_closest v (insert z s) x z"
       by (auto simp: is_closest_def)
     then show ?thesis by metis
   next
     case False
     then obtain a where a: "is_closest v s x a"
       using insert by metis
     then show ?thesis
     proof (cases "\<bar>v a - x\<bar>" "\<bar>v z - x\<bar>" rule: le_cases)
       case le
       then show ?thesis
         by (metis insert_iff a is_closest_def)
     next
       case ge
       have "\<forall>b. b \<in> s \<longrightarrow> \<bar>v a - x\<bar> \<le> \<bar>v b - x\<bar>"
         by (metis a is_closest_def)
       then have "\<forall>b. b \<in> insert z s \<longrightarrow> \<bar>v z - x\<bar> \<le> \<bar>v b - x\<bar>"
         by (metis eq_iff ge insert_iff order.trans)
       then show ?thesis using is_closest_def a
         by (metis insertI1)
     qed
   qed
 qed
 
 lemma closest_is_everything:
   fixes v :: "('e, 'f)float \<Rightarrow> real"
     and s :: "('e, 'f)float set"
   assumes finite: "finite s"
     and non_empty: "s \<noteq> {}"
   shows "is_closest v s x (closest v p s x) \<and>
     ((\<exists>b. is_closest v s x b \<and> p b) \<longrightarrow> p (closest v p s x))"
   unfolding closest_def
   by (rule someI_ex) (metis assms is_closest_exists [of s v x])
 
 lemma closest_in_set:
   fixes v :: "('e, 'f)float \<Rightarrow> real"
   assumes "finite s" and "s \<noteq> {}"
   shows "closest v p s x \<in> s"
   by (metis assms closest_is_everything is_closest_def)
 
 lemma closest_is_closest_finite:
   fixes v :: "('e, 'f)float \<Rightarrow> real"
   assumes "finite s" and "s \<noteq> {}"
   shows "is_closest v s x (closest v p s x)"
   by (metis closest_is_everything assms)
 
 instance float::(len, len) finite proof qed (transfer, simp)
 
 lemma is_finite_nonempty: "{a. is_finite a} \<noteq> {}"
 proof -
   have "0 \<in> {a. is_finite a}"
     unfolding float_defs
     by transfer auto
   then show ?thesis by (metis empty_iff)
 qed
 
 lemma closest_is_closest:
   fixes v :: "('e, 'f)float \<Rightarrow> real"
   assumes "s \<noteq> {}"
   shows "is_closest v s x (closest v p s x)"
   by (rule closest_is_closest_finite) (auto simp: assms)
 
 
 subsection \<open>Properties about ordering and bounding\<close>
 
 text \<open>Lifting of non-exceptional comparisons.\<close>
 lemma float_lt [simp]:
   assumes "is_finite a" "is_finite b"
   shows "a < b \<longleftrightarrow> valof a < valof b"
 proof
   assume "valof a < valof b"
   moreover have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms by (auto simp: finite_nan finite_infinity)
   ultimately have "fcompare a b = Lt"
     by (auto simp add: is_infinity_def is_nan_def valof_def fcompare_def)
   then show "a < b" by (auto simp: float_defs)
 next
   assume "a < b"
   then have lt: "fcompare a b = Lt"
     by (simp add: float_defs)
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms by (auto simp: finite_nan finite_infinity)
   then show "valof a < valof b"
     using lt assms
     by (simp add: fcompare_def is_nan_def is_infinity_def valof_def split: if_split_asm)
 qed
 
 lemma float_eq [simp]:
   assumes "is_finite a" "is_finite b"
   shows "a \<doteq> b \<longleftrightarrow> valof a = valof b"
 proof
   assume *: "valof a = valof b"
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms float_distinct_finite by auto
   with * have "fcompare a b = Eq"
     by (auto simp add: is_infinity_def is_nan_def valof_def fcompare_def)
   then show "a \<doteq> b" by (auto simp: float_defs)
 next
   assume "a \<doteq> b"
   then have eq: "fcompare a b = Eq"
     by (simp add: float_defs)
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms float_distinct_finite by auto
   then show "valof a = valof b"
     using eq assms
     by (simp add: fcompare_def is_nan_def is_infinity_def valof_def split: if_split_asm)
 qed
 
 lemma float_le [simp]:
   assumes "is_finite a" "is_finite b"
   shows "a \<le> b \<longleftrightarrow> valof a \<le> valof b"
 proof -
   have "a \<le> b \<longleftrightarrow>  a < b \<or> a \<doteq> b"
     by (auto simp add: float_defs)
   then show ?thesis
     by (auto simp add: assms)
 qed
 
 text \<open>Reflexivity of equality for non-NaNs.\<close>
 lemma float_eq_refl [simp]: "a \<doteq> a \<longleftrightarrow> \<not> is_nan a"
   by (auto simp: float_defs)
 
 text \<open>Properties about Ordering.\<close>
 lemma float_lt_trans: "is_finite a \<Longrightarrow> is_finite b \<Longrightarrow> is_finite c \<Longrightarrow> a < b \<Longrightarrow> b < c \<Longrightarrow> a < c"
   by (auto simp: le_trans)
 
 lemma float_le_less_trans: "is_finite a \<Longrightarrow> is_finite b \<Longrightarrow> is_finite c \<Longrightarrow> a \<le> b \<Longrightarrow> b < c \<Longrightarrow> a < c"
   by (auto simp: le_trans)
 
 lemma float_le_trans: "is_finite a \<Longrightarrow> is_finite b \<Longrightarrow> is_finite c \<Longrightarrow> a \<le> b \<Longrightarrow> b \<le> c \<Longrightarrow> a \<le> c"
   by (auto simp: le_trans)
 
 lemma float_le_neg: "is_finite a \<Longrightarrow> is_finite b \<Longrightarrow> \<not> a < b \<longleftrightarrow> b \<le> a"
   by auto
 
 
 text \<open>Properties about bounding.\<close>
 
 lemma float_le_infinity [simp]: "\<not> is_nan a \<Longrightarrow> a \<le> plus_infinity"
   unfolding float_defs
   by auto
 
 lemma zero_le_topfloat[simp]: "0 \<le> topfloat" "- 0 \<le> topfloat"
-  by (auto simp: float_defs field_simps power_gt1_lemma of_nat_diff)
+  by (auto simp: float_defs field_simps power_gt1_lemma of_nat_diff mask_eq_exp_minus_1)
 
 lemma LENGTH_contr:
   "Suc 0 < LENGTH('e) \<Longrightarrow> 2 ^ LENGTH('e::len) \<le> Suc (Suc 0) \<Longrightarrow> False"
   by (metis le_antisym len_gt_0 n_less_equal_power_2 not_less_eq numeral_2_eq_2 one_le_numeral
       self_le_power)
 
 lemma valof_topfloat: "valof (topfloat::('e, 'f)float) = largest TYPE(('e, 'f)float)"
   if "LENGTH('e) > 1"
   using that LENGTH_contr
-  by (auto simp add: emax_eq largest_def divide_simps float_defs of_nat_diff)
+  by (auto simp add: emax_eq largest_def divide_simps float_defs of_nat_diff mask_eq_exp_minus_1)
 
 lemma float_frac_le: "fraction a \<le> 2^LENGTH('f) - 1"
   for a::"('e, 'f)float"
   unfolding float_defs
   using less_Suc_eq_le
   by transfer fastforce
 
 lemma float_exp_le: "is_finite a \<Longrightarrow> exponent a \<le> emax TYPE(('e, 'f)float) - 1"
   for a::"('e, 'f)float"
   unfolding float_defs
   by auto
 
 lemma float_sign_le: "(-1::real)^(sign a) = 1 \<or> (-1::real)^(sign a) = -1"
   by (metis neg_one_even_power neg_one_odd_power)
 
 lemma exp_less: "a \<le> b \<Longrightarrow> (2::real)^a \<le> 2^b" for a b :: nat
   by auto
 
 lemma div_less: "a \<le> b \<and> c > 0 \<Longrightarrow> a/c \<le> b/c" for a b c :: "'a::linordered_field"
   by (metis divide_le_cancel less_asym)
 
 lemma finite_topfloat: "is_finite topfloat"
   unfolding float_defs
   by auto
 
 lemmas float_leI = float_le[THEN iffD2]
 
 lemma factor_minus: "x * a - x = x * (a - 1)"
   for x a::"'a::comm_semiring_1_cancel"
   by (simp add: algebra_simps)
 
 lemma real_le_power_numeral_diff: "real a \<le> numeral b ^ n - 1 \<longleftrightarrow> a \<le> numeral b ^ n - 1"
   by (metis (mono_tags, lifting) of_nat_1 of_nat_diff of_nat_le_iff of_nat_numeral
       one_le_numeral one_le_power semiring_1_class.of_nat_power)
 
 definition denormal_exponent::"('e, 'f)float itself \<Rightarrow> int" where
   "denormal_exponent x = 1 - (int (LENGTH('f)) + int (bias TYPE(('e, 'f)float)))"
 
 definition normal_exponent::"('e, 'f)float \<Rightarrow> int" where
   "normal_exponent x = int (exponent x) - int (bias TYPE(('e, 'f)float)) - int (LENGTH('f))"
 
 definition denormal_mantissa::"('e, 'f)float \<Rightarrow> int" where
   "denormal_mantissa x = (-1::int)^sign x * int (fraction x)"
 
 definition normal_mantissa::"('e, 'f)float \<Rightarrow> int" where
   "normal_mantissa x = (-1::int)^sign x * (2^LENGTH('f) + int (fraction x))"
 
 lemma unat_one_word_le: "unat a \<le> Suc 0" for a::"1 word"
   using unat_lt2p[of a]
   by auto
 
 lemma one_word_le: "a \<le> 1" for a::"1 word"
   by (auto simp: word_le_nat_alt unat_one_word_le)
 
 lemma sign_cases[case_names pos neg]:
   obtains "sign x = 0" | "sign x = 1"
 proof cases
   assume "sign x = 0"
   then show ?thesis ..
 next
   assume "sign x \<noteq> 0"
   have "sign x \<le> 1"
     by transfer (auto simp: unat_one_word_le)
   then have "sign x = 1" using \<open>sign x \<noteq> 0\<close>
     by auto
   then show ?thesis ..
 qed
 
 lemma is_infinity_cases:
   assumes "is_infinity x"
   obtains "x = plus_infinity" | "x = minus_infinity"
 proof (cases rule: sign_cases[of x])
   assume "sign x = 0"
   then have "x = plus_infinity" using assms
-    unfolding float_defs
-    by transfer (auto simp: emax_def unat_eq_0 simp flip: word_eq_iff_unsigned)
+    apply (unfold float_defs)
+    apply transfer
+    apply (auto simp add: unat_eq_of_nat emax_def of_nat_mask_eq)
+    done
   then show ?thesis ..
 next
   assume "sign x = 1"
   then have "x = minus_infinity" using assms
-    unfolding float_defs
-    by transfer (auto simp: emax_def unat_eq_of_nat)
+    apply (unfold float_defs)
+    apply transfer
+    apply (auto simp add: unat_eq_of_nat emax_def of_nat_mask_eq)
+    done
   then show ?thesis ..
 qed
 
 lemma is_zero_cases:
   assumes "is_zero x"
   obtains "x = 0" | "x = - 0"
 proof (cases rule: sign_cases[of x])
   assume "sign x = 0"
   then have "x = 0" using assms
     unfolding float_defs
     by transfer (auto simp: emax_def unat_eq_0)
   then show ?thesis ..
 next
   assume "sign x = 1"
   then have "x = minus_zero" using assms
     unfolding float_defs
     by transfer (auto simp: emax_def unat_eq_of_nat)
   then show ?thesis ..
 qed
 
 lemma minus_minus_float[simp]: "- (-f) = f" for f::"('e, 'f)float"
   by transfer auto
 
 lemma sign_minus_float: "sign (-f) = (1 - sign f)" for f::"('e, 'f)float"
   by transfer (auto simp: unat_eq_1 one_word_le unat_sub)
 
 lemma exponent_uminus[simp]: "exponent (- f) = exponent f" by transfer auto
 lemma fraction_uminus[simp]: "fraction (- f) = fraction f" by transfer auto
 
 lemma is_normal_minus_float[simp]: "is_normal (-f) = is_normal f" for f::"('e, 'f)float"
   by (auto simp: is_normal_def)
 
 lemma is_denormal_minus_float[simp]: "is_denormal (-f) = is_denormal f" for f::"('e, 'f)float"
   by (auto simp: is_denormal_def)
 
 lemma bitlen_normal_mantissa:
   "bitlen (abs (normal_mantissa x)) = Suc LENGTH('f)" for x::"('e, 'f)float"
 proof -
   have "fraction x < 2 ^ LENGTH('f)"
     using float_frac_le[of x]
     by (metis One_nat_def Suc_pred le_imp_less_Suc pos2 zero_less_power)
   moreover have "- int (fraction x) \<le> 2 ^ LENGTH('f)"
     using negative_zle_0 order_trans zero_le_numeral zero_le_power by blast
   ultimately show ?thesis
     by (cases x rule: sign_cases)
       (auto simp: bitlen_le_iff_power bitlen_ge_iff_power nat_add_distrib
         normal_mantissa_def intro!: antisym)
 qed
 
 lemma less_int_natI: "x < y" if "0 \<le> x" "nat x < nat y"
   using that by arith
 
 lemma normal_exponent_bounds_int:
   "2 - 2 ^ (LENGTH('e) - 1) - int LENGTH('f) \<le> normal_exponent x"
   "normal_exponent x \<le> 2 ^ (LENGTH('e) - 1) - int LENGTH('f) - 1"
   if "is_normal x"
   for x::"('e, 'f)float"
   using that
-  unfolding normal_exponent_def is_normal_def emax_eq bias_def
-  by (auto simp del: zless_nat_conj intro!: less_int_natI
-      simp: of_nat_diff nat_add_distrib nat_mult_distrib nat_power_eq
-      power_Suc[symmetric])
+   apply (auto simp add: normal_exponent_def is_normal_def emax_eq bias_def diff_le_eq diff_less_eq
+    mask_eq_exp_minus_1 of_nat_diff simp flip: zless_nat_eq_int_zless power_Suc)
+  apply (simp flip: power_Suc mask_eq_exp_minus_1 add: nat_mask_eq)
+  apply (simp add: mask_eq_exp_minus_1)
+  done
 
 lemmas of_int_leI = of_int_le_iff[THEN iffD2]
 
 lemma normal_exponent_bounds_real:
   "2 - 2 ^ (LENGTH('e) - 1) - real LENGTH('f) \<le> normal_exponent x"
   "normal_exponent x \<le> 2 ^ (LENGTH('e) - 1) - real LENGTH('f) - 1"
   if "is_normal x"
   for x::"('e, 'f)float"
   subgoal by (rule order_trans[OF _ of_int_leI[OF normal_exponent_bounds_int(1)[OF that]]]) auto
   subgoal by (rule order_trans[OF of_int_leI[OF normal_exponent_bounds_int(2)[OF that]]]) auto
   done
 
 lemma float_eqI:
   "x = y" if "sign x = sign y" "fraction x = fraction y" "exponent x = exponent y"
   using that by transfer (auto simp add: word_unat_eq_iff)
 
 lemma float_induct[induct type:float, case_names normal denormal neg zero infinity nan]:
   fixes a::"('e, 'f)float"
   assumes normal:
     "\<And>x. is_normal x \<Longrightarrow> valof x = normal_mantissa x * 2 powr normal_exponent x \<Longrightarrow> P x"
   assumes denormal:
     "\<And>x. is_denormal x \<Longrightarrow>
       valof x = denormal_mantissa x * 2 powr denormal_exponent TYPE(('e, 'f)float) \<Longrightarrow>
       P x"
   assumes zero: "P 0" "P minus_zero"
   assumes infty: "P plus_infinity" "P minus_infinity"
   assumes nan: "\<And>x. is_nan x \<Longrightarrow> P x"
   shows "P a"
 proof -
   from float_cases[of a]
   consider "is_nan a" | "is_infinity a" | "is_normal a" | "is_denormal a" | "is_zero a" by blast
   then show ?thesis
   proof cases
     case 1
     then show ?thesis by (rule nan)
   next
     case 2
     then consider "a = plus_infinity" | "a = minus_infinity" by (rule is_infinity_cases)
     then show ?thesis
       by cases (auto intro: infty)
   next
     case hyps: 3
     from hyps have "valof a = normal_mantissa a * 2 powr normal_exponent a"
       by (cases a rule: sign_cases)
         (auto simp: valof_eq normal_mantissa_def normal_exponent_def is_normal_def
-          powr_realpow[symmetric] powr_diff powr_add divide_simps algebra_simps)
+          powr_realpow[symmetric] powr_diff powr_add field_simps)
     from hyps this show ?thesis
       by (rule normal)
   next
     case hyps: 4
     from hyps have "valof a = denormal_mantissa a * 2 powr denormal_exponent TYPE(('e, 'f)float)"
       by (cases a rule: sign_cases)
         (auto simp: valof_eq denormal_mantissa_def denormal_exponent_def is_denormal_def
-          powr_realpow[symmetric] powr_diff powr_add divide_simps algebra_simps)
+          powr_realpow[symmetric] powr_diff powr_add field_simps)
     from hyps this show ?thesis
       by (rule denormal)
   next
     case 5
     then consider "a = 0" | "a = minus_zero" by (rule is_zero_cases)
     then show ?thesis
       by cases (auto intro: zero)
   qed
 qed
 
 lemma infinite_infinity[simp]: "\<not> is_finite plus_infinity" "\<not> is_finite minus_infinity"
   by (auto simp: is_finite_def is_normal_def infinity_simps is_denormal_def is_zero_def)
 
 lemma nan_not_finite[simp]: "is_nan x \<Longrightarrow> \<not> is_finite x"
   using float_distinct_finite(1) by blast
 
 lemma valof_nonneg:
   "valof x \<ge> 0" if "sign x = 0" for x::"('e, 'f)float"
   by (auto simp: valof_eq that)
 
 lemma valof_nonpos:
   "valof x \<le> 0" if "sign x = 1" for x::"('e, 'f)float"
   using that
   by (auto simp: valof_eq is_finite_def)
 
 lemma real_le_intI: "x \<le> y" if "floor x \<le> floor y" "x \<in> \<int>" for x y::real
   using that(2,1)
   by (induction rule: Ints_induct) (auto elim!: Ints_induct simp: le_floor_iff)
 
 lemma real_of_int_le_2_powr_bitlenI:
   "real_of_int x \<le> 2 powr n - 1" if "bitlen (abs x) \<le> m" "m \<le> n"
 proof -
   have "real_of_int x \<le> abs (real_of_int x)" by simp
   also have "\<dots> < 2 powr (bitlen (abs x))"
     by (rule abs_real_le_2_powr_bitlen)
   finally have "real_of_int x \<le> 2 powr (bitlen (abs x)) - 1"
     by (auto simp: powr_real_of_int bitlen_nonneg intro!: real_le_intI)
   also have "\<dots> \<le> 2 powr m - 1"
     by (simp add: that)
   also have "\<dots> \<le> 2 powr n - 1"
     by (simp add: that)
   finally show ?thesis .
 qed
 
 lemma largest_eq:
   "largest TYPE(('e, 'f)float) =
     (2 ^ (LENGTH('f) + 1) - 1) * 2 powr real_of_int (2 ^ (LENGTH('e) - 1) - int LENGTH('f) - 1)"
 proof -
   have "2 ^ LENGTH('e) - 1 - 1 = (2::nat) ^ LENGTH('e) - 2"
     by arith
   then have "largest TYPE(('e, 'f)float) =
     (2 ^ (LENGTH('f) + 1) - 1) *
     2 powr (real (2 ^ LENGTH('e) - 2) + 1 - real (2 ^ (LENGTH('e) - 1)) - LENGTH('f))"
-    unfolding largest_def emax_eq bias_def
-    by (auto simp: largest_def powr_realpow[symmetric]
-        powr_minus divide_simps algebra_simps powr_diff powr_add of_nat_diff)
+    by (auto simp add: largest_def emax_eq bias_def powr_minus field_simps powr_diff powr_add of_nat_diff
+      mask_eq_exp_minus_1 simp flip: powr_realpow)
   also
   have "2 ^ LENGTH('e) \<ge> (2::nat)"
     by (simp add: self_le_power)
   then have "(real (2 ^ LENGTH('e) - 2) + 1 - real (2 ^ (LENGTH('e) - 1)) - LENGTH('f)) =
     (real (2 ^ LENGTH('e)) - 2 ^ (LENGTH('e) - 1) - LENGTH('f)) - 1"
     by (auto simp add: of_nat_diff)
   also have "real (2 ^ LENGTH('e)) = 2 ^ LENGTH('e)" by auto
   also have "(2 ^ LENGTH('e) - 2 ^ (LENGTH('e) - 1) - real LENGTH('f) - 1) =
     real_of_int ((2 ^ (LENGTH('e) - 1) - int (LENGTH('f)) - 1))"
     by (simp, subst power_Suc[symmetric], simp)
   finally show ?thesis by simp
 qed
 
 lemma bitlen_denormal_mantissa:
   "bitlen (abs (denormal_mantissa x)) \<le> LENGTH('f)" for x::"('e, 'f)float"
 proof -
   have "fraction x < 2 ^ LENGTH('f)"
     using float_frac_le[of x]
     by (metis One_nat_def Suc_pred le_imp_less_Suc pos2 zero_less_power)
   moreover have "- int (fraction x) \<le> 2 ^ LENGTH('f)"
     using negative_zle_0 order_trans zero_le_numeral zero_le_power by blast
   ultimately show ?thesis
     by (cases x rule: sign_cases)
       (auto simp: bitlen_le_iff_power denormal_mantissa_def intro!: antisym)
 qed
 
 lemma float_le_topfloat:
   fixes a::"('e, 'f)float"
   assumes "is_finite a" "LENGTH('e) > 1"
   shows "a \<le> topfloat"
   using assms(1)
 proof (induction a rule: float_induct)
   case (normal x)
   note normal(2)
   also have "real_of_int (normal_mantissa x) * 2 powr real_of_int (normal_exponent x) \<le>
     (2 powr (LENGTH('f) + 1) - 1) * 2 powr (2 ^ (LENGTH('e) - 1) - int LENGTH('f) - 1)"
     using normal_exponent_bounds_real(2)[OF \<open>is_normal x\<close>]
     by (auto intro!: mult_mono real_of_int_le_2_powr_bitlenI
         simp: bitlen_normal_mantissa powr_realpow[symmetric] ge_one_powr_ge_zero)
   also have "\<dots> = largest TYPE(('e, 'f) IEEE.float)"
     unfolding largest_eq
     by (auto simp: powr_realpow powr_add)
   also have "\<dots> = valof (topfloat::('e, 'f) float)"
     using assms
     by (simp add: valof_topfloat)
   finally show ?case
     by (intro float_leI normal finite_topfloat)
 next
   case (denormal x)
   note denormal(2)
   also
   have "3 \<le> 2 powr (1 + real (LENGTH('e) - Suc 0))"
   proof -
     have "3 \<le> 2 powr (2::real)" by simp
     also have "\<dots> \<le> 2 powr (1 + real (LENGTH('e) - Suc 0))"
       using assms
       by (subst powr_le_cancel_iff) auto
     finally show ?thesis .
   qed
   then have "real_of_int (denormal_mantissa x) * 2 powr real_of_int (denormal_exponent TYPE(('e, 'f)float)) \<le>
     (2 powr (LENGTH('f) + 1) - 1) * 2 powr (2 ^ (LENGTH('e) - 1) - int LENGTH('f) - 1)"
     using bitlen_denormal_mantissa[of x]
     by (auto intro!: mult_mono real_of_int_le_2_powr_bitlenI
-        simp: bitlen_normal_mantissa powr_realpow[symmetric] ge_one_powr_ge_zero
+        simp: bitlen_normal_mantissa powr_realpow[symmetric] ge_one_powr_ge_zero mask_eq_exp_minus_1
         denormal_exponent_def bias_def powr_mult_base of_nat_diff)
   also have "\<dots> \<le> largest TYPE(('e, 'f) IEEE.float)"
     unfolding largest_eq
     by (rule mult_mono)
       (auto simp: powr_realpow powr_add power_Suc[symmetric] simp del: power_Suc)
   also have "\<dots> = valof (topfloat::('e, 'f) float)"
     using assms
     by (simp add: valof_topfloat)
   finally show ?case
     by (intro float_leI denormal finite_topfloat)
 qed auto
 
 lemma float_val_le_largest:
   "valof a \<le> largest TYPE(('e, 'f)float)"
   if "is_finite a" "LENGTH('e) > 1"
   for a::"('e, 'f)float"
   by (metis that finite_topfloat float_le float_le_topfloat valof_topfloat)
 
 lemma float_val_lt_threshold:
   "valof a < threshold TYPE(('e, 'f)float)"
   if "is_finite a" "LENGTH('e) > 1"
   for a::"('e, 'f)float"
 proof -
   have "valof a \<le> largest TYPE(('e, 'f)float)"
     by (rule float_val_le_largest [OF that])
   also have "\<dots> < threshold TYPE(('e, 'f)float)"
     by (auto simp: largest_def threshold_def divide_simps)
   finally show ?thesis .
 qed
 
 
 subsection \<open>Algebraic properties about basic arithmetic\<close>
 
 text \<open>Commutativity of addition.\<close>
 lemma
   assumes "is_finite a" "is_finite b"
   shows float_plus_comm_eq: "a + b = b + a"
     and float_plus_comm: "is_finite (a + b) \<Longrightarrow> (a + b) \<doteq> (b + a)"
 proof -
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms by (auto simp: finite_nan finite_infinity)
   then show "a + b = b + a"
     by (simp add: float_defs fadd_def plus_float_def add.commute)
   then show "is_finite (a + b) \<Longrightarrow> (a + b) \<doteq> (b + a)"
     by (metis float_eq)
 qed
 
 text \<open>The floating-point number a falls into the same category as the negation of \<open>a\<close>.\<close>
 lemma is_zero_uminus[simp]: "is_zero (- a) \<longleftrightarrow> is_zero a"
   by (simp add: is_zero_def)
 
 lemma is_infinity_uminus [simp]: "is_infinity (- a) = is_infinity a"
   by (simp add: is_infinity_def)
 
 lemma is_finite_uminus[simp]: "is_finite (- a) \<longleftrightarrow> is_finite a"
   by (simp add: is_finite_def)
 
 lemma is_nan_uminus[simp]: "is_nan (- a) \<longleftrightarrow> is_nan a"
   by (simp add: is_nan_def)
 
 text \<open>The sign of a and the sign of a's negation is different.\<close>
 lemma float_neg_sign: "(sign a) \<noteq> (sign (- a))"
   by (cases a rule: sign_cases) (auto simp: sign_minus_float)
 
 lemma float_neg_sign1: "sign a = sign (- b) \<longleftrightarrow> sign a \<noteq> sign b"
   by (metis float_neg_sign sign_cases)
 
 lemma valof_uminus:
   assumes "is_finite a"
   shows "valof (- a) = - valof a" (is "?L = ?R")
   by (cases a rule: sign_cases)  (auto simp: valof_eq sign_minus_float)
 
 
 text \<open>Showing \<open>a + (- b) = a - b\<close>.\<close>
 lemma float_neg_add:
   "is_finite a \<Longrightarrow> is_finite b \<Longrightarrow> is_finite (a - b) \<Longrightarrow> valof a + valof (- b) = valof a - valof b"
   by (simp add: valof_uminus)
 
 lemma float_plus_minus:
   assumes "is_finite a" "is_finite b" "is_finite (a - b)"
   shows "(a + - b) \<doteq> (a - b)"
 proof -
   have nab: "\<not> is_nan a" "\<not> is_nan (- b)" "\<not> is_infinity a" "\<not> is_infinity (-  b)"
     using assms by (auto simp: finite_nan finite_infinity)
   have "a - b = (zerosign
         (if is_zero a \<and> is_zero b \<and> sign a \<noteq> sign b then (sign a) else 0)
         (round To_nearest (valof a - valof b)))"
     using nab
     by (auto simp: minus_float_def fsub_def)
   also have "\<dots> =
     (zerosign
         (if is_zero a \<and> is_zero (- b) \<and> sign a = sign (- b) then sign a else 0)
         (round To_nearest (valof a + valof (- b))))"
     using assms
     by (simp add: float_neg_sign1 float_neg_add)
   also have "\<dots> = a + - b"
     using nab by (auto simp: float_defs fadd_def plus_float_def)
   finally show ?thesis
     using assms by (metis float_eq)
 qed
 
 lemma finite_bottomfloat: "is_finite bottomfloat"
   by (simp add: finite_topfloat)
 
 lemma bottomfloat_eq_m_largest: "valof (bottomfloat::('e, 'f)float) = - largest TYPE(('e, 'f)float)"
   if "LENGTH('e) > 1"
   using that
   by (auto simp: valof_topfloat valof_uminus finite_topfloat)
 
 lemma float_val_ge_bottomfloat: "valof a \<ge> valof (bottomfloat::('e, 'f)float)"
   if "LENGTH('e) > 1" "is_finite a"
   for a::"('e,'f)float"
 proof -
   have "- a \<le> topfloat"
     using that
     by (auto intro: float_le_topfloat)
   then show ?thesis
     using that
     by (auto simp: valof_uminus finite_topfloat)
 qed
 
 lemma float_ge_bottomfloat: "is_finite a \<Longrightarrow> a \<ge> bottomfloat"
   if "LENGTH('e) > 1" "is_finite a"
   for a::"('e,'f)float"
   by (metis finite_bottomfloat float_le float_val_ge_bottomfloat that)
 
 lemma float_val_ge_largest:
   fixes a::"('e,'f)float"
   assumes "LENGTH('e) > 1" "is_finite a"
   shows "valof a \<ge> - largest TYPE(('e,'f)float)"
 proof -
   have "- largest TYPE(('e,'f)float) = valof (bottomfloat::('e,'f)float)"
     using assms
     by (simp add: bottomfloat_eq_m_largest)
   also have "\<dots> \<le> valof a"
     using assms by (simp add: float_val_ge_bottomfloat)
   finally show ?thesis .
 qed
 
 lemma float_val_gt_threshold:
   fixes a::"('e,'f)float"
   assumes "LENGTH('e) > 1" "is_finite a"
   shows "valof a > - threshold TYPE(('e,'f)float)"
 proof -
   have largest: "valof a \<ge> -largest TYPE(('e,'f)float)"
     using assms by (metis float_val_ge_largest)
   then have "-largest TYPE(('e,'f)float) > - threshold TYPE(('e,'f)float)"
     by (auto simp: bias_def threshold_def largest_def divide_simps)
   then show ?thesis
     by (metis largest less_le_trans)
 qed
 
 text \<open>Showing \<open>abs (- a) = abs a\<close>.\<close>
 lemma float_abs [simp]: "\<not> is_nan a \<Longrightarrow> abs (- a) = abs a"
   by (metis IEEE.abs_float_def float_neg_sign1 minus_minus_float zero_simps(1))
 
 lemma neg_zerosign: "- (zerosign s a) = zerosign (1 - s) (- a)"
   by (auto simp: zerosign_def)
 
 
 subsection \<open>Properties about Rounding Errors\<close>
 
 definition error :: "('e, 'f)float itself \<Rightarrow> real \<Rightarrow> real"
   where "error _ x = valof (round To_nearest x::('e, 'f)float) - x"
 
 lemma bound_at_worst_lemma:
   fixes a::"('e, 'f)float"
   assumes threshold: "\<bar>x\<bar> < threshold TYPE(('e, 'f)float)"
   assumes finite: "is_finite a"
   shows "\<bar>valof (round To_nearest x::('e, 'f)float) - x\<bar> \<le> \<bar>valof a - x\<bar>"
 proof -
   have *: "(round To_nearest x::('e,'f)float) =
       closest valof (\<lambda>a. even (fraction a)) {a. is_finite a} x"
     using threshold finite
     by auto
   have "is_closest (valof) {a. is_finite a} x (round To_nearest x::('e,'f)float)"
     using is_finite_nonempty
     unfolding *
     by (intro closest_is_closest) auto
   then show ?thesis
     using finite is_closest_def by (metis mem_Collect_eq)
 qed
 
 lemma error_at_worst_lemma:
   fixes a::"('e, 'f)float"
   assumes threshold: "\<bar>x\<bar> < threshold TYPE(('e, 'f)float)"
     and "is_finite a"
   shows "\<bar>error TYPE(('e, 'f)float) x\<bar> \<le> \<bar>valof a - x\<bar> "
   unfolding error_def
   by (rule bound_at_worst_lemma; fact)
 
 lemma error_is_zero [simp]:
   fixes a::"('e, 'f)float"
   assumes "is_finite a" "1 < LENGTH('e)"
   shows "error TYPE(('e, 'f)float) (valof a) = 0"
 proof -
   have "\<bar>valof a\<bar> < threshold TYPE(('e, 'f)float)"
     by (metis abs_less_iff minus_less_iff float_val_gt_threshold float_val_lt_threshold assms)
   then show ?thesis
     by (metis abs_le_zero_iff abs_zero diff_self error_at_worst_lemma assms(1))
 qed
 
 lemma is_finite_zerosign[simp]: "is_finite (zerosign s a) \<longleftrightarrow> is_finite a"
   by (auto simp: zerosign_def is_finite_def)
 
 lemma is_finite_closest: "is_finite (closest (v::_\<Rightarrow>real) p {a. is_finite a} x)"
   using closest_is_closest[OF is_finite_nonempty, of v x p]
   by (auto simp: is_closest_def)
 
 lemma defloat_float_zerosign_round_finite:
   assumes threshold: "\<bar>x\<bar> < threshold TYPE(('e, 'f)float)"
   shows "is_finite (zerosign s (round To_nearest x::('e, 'f)float))"
 proof -
   have "(round To_nearest x::('e, 'f)float) =
       (closest valof (\<lambda>a. even (fraction a)) {a. is_finite a} x)"
     using threshold by (metis (full_types) abs_less_iff leD le_minus_iff round.simps(1))
   then have "is_finite (round To_nearest x::('e, 'f)float)"
     by (metis is_finite_closest)
   then show ?thesis
     using is_finite_zerosign by auto
 qed
 
 lemma valof_zero[simp]: "valof 0 = 0" "valof minus_zero = 0"
   by (auto simp add: zerosign_def valof_eq zero_simps)
 
 lemma signzero_zero:
   "is_zero a \<Longrightarrow> valof (zerosign s a) = 0"
   by (auto simp add: zerosign_def)
 
 lemma val_zero: "is_zero a \<Longrightarrow> valof a = 0"
   by (cases a rule: is_zero_cases) auto
 
 lemma float_add:
   fixes a b::"('e, 'f)float"
   assumes "is_finite a"
     and "is_finite b"
     and threshold: "\<bar>valof a + valof b\<bar> < threshold TYPE(('e, 'f)float)"
   shows finite_float_add: "is_finite (a + b)"
     and error_float_add:  "valof (a + b) = valof a + valof b + error TYPE(('e, 'f)float) (valof a + valof b)"
 proof -
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms float_distinct_finite by auto
   then have ab: "(a + b) =
     (zerosign
       (if is_zero a \<and> is_zero b \<and> sign a = sign b then (sign a) else 0)
       (round To_nearest (valof a + valof b)))"
     using assms by (auto simp add: float_defs fadd_def plus_float_def)
   then show "is_finite ((a + b))"
     by (metis threshold defloat_float_zerosign_round_finite)
   have val_ab: "valof (a + b) =
     valof (zerosign
       (if is_zero a \<and> is_zero b \<and> sign a = sign b then (sign a) else 0)
       (round To_nearest (valof a + valof b)::('e, 'f)float))"
     by (auto simp: ab is_infinity_def is_nan_def valof_def)
   show "valof (a + b) = valof a + valof b + error TYPE(('e, 'f)float) (valof a + valof b)"
   proof (cases "is_zero (round To_nearest (valof a + valof b)::('e, 'f)float)")
     case True
     have "valof a + valof b + error TYPE(('e, 'f)float) (valof a + valof b) =
         valof (round To_nearest (valof a + valof b)::('e, 'f)float)"
       unfolding error_def
       by simp
     then show ?thesis
       by (metis True signzero_zero val_zero val_ab)
   next
     case False
     then show ?thesis
       by (metis ab add.commute eq_diff_eq' error_def zerosign_def)
   qed
 qed
 
 lemma float_sub:
   fixes a b::"('e, 'f)float"
   assumes "is_finite a"
     and "is_finite b"
     and threshold: "\<bar>valof a - valof b\<bar> < threshold TYPE(('e, 'f)float)"
   shows finite_float_sub: "is_finite (a - b)"
     and error_float_sub: "valof (a - b) = valof a - valof b + error TYPE(('e, 'f)float) (valof a - valof b)"
 proof -
   have "\<not> is_nan a" and "\<not> is_nan b" and "\<not> is_infinity a" and "\<not> is_infinity b"
     using assms by (auto simp: finite_nan finite_infinity)
   then have ab: "a - b =
     (zerosign
       (if is_zero a \<and> is_zero b \<and> sign a \<noteq> sign b then sign a else 0)
       (round To_nearest (valof a - valof b)))"
     using assms by (auto simp add: float_defs fsub_def minus_float_def)
   then show "is_finite (a - b)"
    by (metis threshold defloat_float_zerosign_round_finite)
   have val_ab: "valof (a - b) =
     valof (zerosign
       (if is_zero a \<and> is_zero b \<and> sign a \<noteq> sign b then sign a else 0)
       (round To_nearest (valof a - valof b)::('e, 'f)float))"
     by (auto simp: ab is_infinity_def is_nan_def valof_def)
   show "valof (a - b) = valof a - valof b + error TYPE(('e, 'f)float) (valof a - valof b)"
   proof (cases "is_zero (round To_nearest (valof a - valof b)::('e, 'f)float)")
     case True
     have "valof a - valof b + error TYPE(('e, 'f)float) (valof a - valof b) =
         valof (round To_nearest (valof a - valof b)::('e, 'f)float)"
       unfolding error_def by simp
     then show ?thesis
       by (metis True signzero_zero val_zero val_ab)
   next
     case False
     then show ?thesis
       by (metis ab add.commute eq_diff_eq' error_def zerosign_def)
   qed
 qed
 
 lemma float_mul:
   fixes a b::"('e, 'f)float"
   assumes "is_finite a"
     and "is_finite b"
     and threshold: "\<bar>valof a * valof b\<bar> < threshold TYPE(('e, 'f)float)"
   shows finite_float_mul: "is_finite (a * b)"
     and error_float_mul: "valof (a * b) = valof a * valof b + error TYPE(('e, 'f)float) (valof a * valof b)"
 proof -
   have non: "\<not> is_nan a" "\<not> is_nan b" "\<not> is_infinity a" "\<not> is_infinity b"
     using assms float_distinct_finite by auto
   then have ab: "a * b =
     (zerosign (of_bool (sign a \<noteq> sign b))
       (round To_nearest (valof a * valof b)::('e, 'f)float))"
     using assms by (auto simp: float_defs fmul_def times_float_def)
   then show "is_finite (a * b)"
     by (metis threshold defloat_float_zerosign_round_finite)
   have val_ab: "valof (a * b) =
       valof (zerosign (of_bool (sign a \<noteq> sign b))
         (round To_nearest (valof a * valof b)::('e, 'f)float))"
     by (auto simp: ab float_defs of_bool_def)
   show "valof (a * b) = valof a * valof b + error TYPE(('e, 'f)float) (valof a * valof b)"
   proof (cases "is_zero (round To_nearest (valof a * valof b)::('e, 'f)float)")
     case True
     have "valof a * valof b + error TYPE(('e, 'f)float)  (valof a * valof b) =
         valof (round To_nearest (valof a * valof b)::('e, 'f)float)"
       unfolding error_def
       by simp
     then show ?thesis
       by (metis True signzero_zero val_zero val_ab)
   next
     case False then show ?thesis
       by (metis ab add.commute eq_diff_eq' error_def zerosign_def)
   qed
 qed
 
 lemma float_div:
   fixes a b::"('e, 'f)float"
   assumes "is_finite a"
     and "is_finite b"
     and not_zero: "\<not> is_zero b"
     and threshold: "\<bar>valof a / valof b\<bar> < threshold TYPE(('e, 'f)float)"
   shows finite_float_div: "is_finite (a / b)"
     and error_float_div: "valof (a / b) = valof a / valof b + error TYPE(('e, 'f)float) (valof a / valof b)"
 proof -
   have ab: "a / b =
     (zerosign (of_bool (sign a \<noteq> sign b))
       (round To_nearest (valof a / valof b)))"
      using assms
      by (simp add: divide_float_def fdiv_def finite_infinity finite_nan not_zero float_defs [symmetric])
   then show "is_finite (a / b)"
     by (metis threshold defloat_float_zerosign_round_finite)
   have val_ab: "valof (a / b) =
       valof (zerosign (of_bool (sign a \<noteq> sign b))
         (round To_nearest (valof a / valof b))::('e, 'f)float)"
     by (auto simp: ab float_defs of_bool_def)
   show "valof (a / b) = valof a / valof b + error TYPE(('e, 'f)float)  (valof a / valof b)"
   proof (cases "is_zero (round To_nearest (valof a / valof b)::('e, 'f)float)")
     case True
     have "valof a / valof b + error TYPE(('e, 'f)float) (valof a / valof b) =
         valof (round To_nearest (valof a / valof b)::('e, 'f)float)"
       unfolding error_def
       by simp
     then show ?thesis
       by (metis True signzero_zero val_zero val_ab)
   next
     case False then show ?thesis
       by (metis ab add.commute eq_diff_eq' error_def zerosign_def)
   qed
 qed
 
-lemma valof_one[simp]: "valof (1::('e, 'f)float) = (if LENGTH('e) \<le> 1 then 0 else 1)"
-  by transfer (auto simp: bias_def unat_sub word_1_le_power p2_eq_1)
+lemma valof_one[simp]: "valof (1 :: ('e, 'f) float) = of_bool (LENGTH('e) > 1)"
+  apply transfer
+  apply (auto simp add: bias_def unat_mask_eq simp flip: mask_eq_exp_minus_1)
+  apply (simp add: mask_eq_exp_minus_1)
+  done
 
 end
diff --git a/thys/IP_Addresses/IP_Address.thy b/thys/IP_Addresses/IP_Address.thy
--- a/thys/IP_Addresses/IP_Address.thy
+++ b/thys/IP_Addresses/IP_Address.thy
@@ -1,421 +1,422 @@
 (*  Title:      IP_Address.thy
     Authors:    Cornelius Diekmann
 *)
 theory IP_Address
   imports
     Word_Lib.Word_Lemmas
     Word_Lib.Word_Syntax
     Word_Lib.Reversed_Bit_Lists
     Hs_Compat
     WordInterval
 begin
 
+ 
 section \<open>Modelling IP Adresses\<close>
   text\<open>An IP address is basically an unsigned integer.
     We model IP addresses of arbitrary lengths.
 
     We will write @{typ "'i::len word"} for IP addresses of length @{term "LENGTH('i::len)"}.
     We use the convention to write @{typ 'i} whenever we mean IP addresses instead of generic words.
     When we will later have theorems with several polymorphic types in it (e.g. arbitrarily
     extensible packets), this notation makes it easier to spot that type @{typ 'i} is for
     IP addresses.
 
     The files @{file \<open>IPv4.thy\<close>} @{file \<open>IPv6.thy\<close>} concrete this for IPv4 and IPv6.\<close>
 
   text\<open>The maximum IP address\<close>
   definition max_ip_addr :: "'i::len word" where
     "max_ip_addr \<equiv> of_nat ((2^(len_of(TYPE('i)))) - 1)"
 
   lemma max_ip_addr_max_word: "max_ip_addr = - 1"
     by (simp only: max_ip_addr_def of_nat_mask_eq flip: mask_eq_exp_minus_1) simp
 
   lemma max_ip_addr_max: "\<forall>a. a \<le> max_ip_addr"
     by(simp add: max_ip_addr_max_word)
   lemma range_0_max_UNIV: "UNIV = {0 .. max_ip_addr}" (*not in the simp set, for a reason*)
     by(simp add: max_ip_addr_max_word) fastforce
 
   lemma "size (x::'i::len word) = len_of(TYPE('i))" by(simp add:word_size)
 
 subsection\<open>Sets of IP Addresses\<close>
 
   context
     includes bit_operations_syntax
   begin
 
   (*Warning, not executable!*)
   text\<open>Specifying sets with network masks: 192.168.0.0 255.255.255.0\<close>
   definition ipset_from_netmask::"'i::len word \<Rightarrow> 'i::len word \<Rightarrow> 'i::len word set" where
     "ipset_from_netmask addr netmask \<equiv>
       let
         network_prefix = (addr AND netmask)
       in
         {network_prefix .. network_prefix OR (NOT netmask)}"
 
   text\<open>Example (pseudo syntax):
     @{const ipset_from_netmask} \<open>192.168.1.129  255.255.255.0\<close> =
         \<open>{192.168.1.0 .. 192.168.1.255}\<close>\<close>
 
   text\<open>A network mask of all ones (i.e. @{term "(- 1)::'i::len word"}).\<close>
   lemma ipset_from_netmask_minusone:
     "ipset_from_netmask ip (- 1) = {ip}" by (simp add: ipset_from_netmask_def)
   lemma ipset_from_netmask_maxword:
     "ipset_from_netmask ip (- 1) = {ip}" by (simp add: ipset_from_netmask_def)
 
   lemma ipset_from_netmask_zero:
     "ipset_from_netmask ip 0 = UNIV" by (auto simp add: ipset_from_netmask_def)
 
 
   text\<open>Specifying sets in Classless Inter-domain Routing (CIDR) notation: 192.168.0.0/24\<close>
   definition ipset_from_cidr ::"'i::len word \<Rightarrow> nat \<Rightarrow> 'i::len word set" where
     "ipset_from_cidr addr pflength \<equiv>
        ipset_from_netmask addr ((mask pflength) << (len_of(TYPE('i)) - pflength))"
 
   text\<open>Example (pseudo syntax):
     @{const ipset_from_cidr} \<open>192.168.1.129 24\<close> = \<open>{192.168.1.0 .. 192.168.1.255}\<close>\<close>
 
   (*does this simplify stuff?*)
   lemma "(case ipcidr of (base, len) \<Rightarrow> ipset_from_cidr base len) = uncurry ipset_from_cidr ipcidr"
     by(simp add: uncurry_case_stmt)
 
   lemma ipset_from_cidr_0: "ipset_from_cidr ip 0 = UNIV"
     by(auto simp add: ipset_from_cidr_def ipset_from_netmask_def Let_def)
 
   text\<open>A prefix length of word size gives back the singleton set with the IP address.
        Example: \<open>192.168.1.2/32 = {192.168.1.2}\<close>\<close>
   lemma ipset_from_cidr_wordlength:
     fixes ip :: "'i::len word"
     shows "ipset_from_cidr ip (LENGTH('i)) = {ip}"
     by (simp add: ipset_from_cidr_def ipset_from_netmask_def)
 
   text\<open>Alternative definition: Considering words as bit lists:\<close>
   lemma ipset_from_cidr_bl:
     fixes addr :: "'i::len word"
     shows "ipset_from_cidr addr pflength \<equiv>
             ipset_from_netmask addr (of_bl ((replicate pflength True) @
                                             (replicate ((len_of(TYPE('i))) - pflength)) False))"
     by(simp add: ipset_from_cidr_def mask_bl shiftl_of_bl)
 
   lemma ipset_from_cidr_alt:
     fixes pre :: "'i::len word"
     shows "ipset_from_cidr pre len =
             {pre AND (mask len << LENGTH('i) - len)
              ..
              pre OR mask (LENGTH('i) - len)}"
     apply(simp add: ipset_from_cidr_def ipset_from_netmask_def Let_def)
     apply(simp add: word_oa_dist)
     apply(simp add: NOT_mask_shifted_lenword)
     done
 
   lemma ipset_from_cidr_alt2:
     fixes base ::"'i::len word"
     shows "ipset_from_cidr base len =
            ipset_from_netmask base (NOT (mask (LENGTH('i) - len)))"
     apply(simp add: ipset_from_cidr_def)
     using NOT_mask_shifted_lenword by(metis word_not_not)
 
   text\<open>In CIDR notation, we cannot express the empty set.\<close>
   lemma ipset_from_cidr_not_empty: "ipset_from_cidr base len \<noteq> {}"
     by(simp add: ipset_from_cidr_alt bitmagic_zeroLast_leq_or1Last)
 
   text\<open>Though we can write 192.168.1.2/24, we say that 192.168.0.0/24 is well-formed.\<close>
   lemma ipset_from_cidr_base_wellforemd: fixes base:: "'i::len word"
     assumes "mask (LENGTH('i) - l) AND base = 0"
       shows "ipset_from_cidr base l = {base .. base OR mask (LENGTH('i) - l)}"
   proof -
     have maskshift_eq_not_mask_generic:
       "((mask l << LENGTH('i) - l) :: 'i::len word) = NOT (mask (LENGTH('i) - l))"
       using NOT_mask_shifted_lenword by (metis word_not_not)
     have *: "base AND NOT (mask (LENGTH('i) - l)) = base"
       unfolding mask_eq_0_eq_x[symmetric] using assms word_bw_comms(1)[of base] by simp
     hence **: "base AND NOT (mask (LENGTH('i) - l)) OR mask (LENGTH('i) - l) =
                 base OR mask (LENGTH('i) - l)" by simp
     have "ipset_from_netmask base (NOT (mask (LENGTH('i) - l))) =
             {base .. base || mask (LENGTH('i) - l)}"
       by(simp add: ipset_from_netmask_def Let_def ** *)
     thus ?thesis by(simp add: ipset_from_cidr_def maskshift_eq_not_mask_generic)
   qed
 
 
   lemma ipset_from_cidr_large_pfxlen:
     fixes ip:: "'i::len word"
     assumes "n \<ge> LENGTH('i)"
     shows "ipset_from_cidr ip n = {ip}"
   proof -
     have obviously: "mask (LENGTH('i) - n) = 0" by (simp add: assms)
     show ?thesis
       apply(subst ipset_from_cidr_base_wellforemd)
        subgoal using assms by simp
       by (simp add: obviously)
   qed
 
   lemma ipset_from_netmask_base_mask_consume:
     fixes base :: "'i::len word"
     shows "ipset_from_netmask (base AND NOT (mask (LENGTH('i) - m)))
                               (NOT (mask (LENGTH('i) - m)))
             =
              ipset_from_netmask base (NOT (mask (LENGTH('i) - m)))"
     unfolding ipset_from_netmask_def by(simp)
 
 
   text\<open>Another definition of CIDR notation:
        All IP address which are equal on the first @{term "len - n"} bits\<close>
   definition ip_cidr_set :: "'i::len word \<Rightarrow> nat \<Rightarrow> 'i word set" where
     "ip_cidr_set i r \<equiv>
       {j . i AND NOT (mask (LENGTH('i) - r)) = j AND NOT (mask (LENGTH('i) - r))}"
 
   text\<open>The definitions are equal\<close>
   lemma ipset_from_cidr_eq_ip_cidr_set:
     fixes base::"'i::len word"
     shows "ipset_from_cidr base len = ip_cidr_set base len"
   proof -
     have maskshift_eq_not_mask_generic:
       "((mask len << LENGTH('a) - len) :: 'a::len word) = NOT (mask (LENGTH('a) - len))"
       using NOT_mask_shifted_lenword by (metis word_not_not)
     have 1: "mask (len - m) AND base AND NOT (mask (len - m)) = 0"
       for len m and base::"'i::len word"
       by(simp add: word_bw_lcs)
     have 2: "mask (LENGTH('i) - len) AND pfxm_p = 0 \<Longrightarrow>
            (a \<in> ipset_from_netmask pfxm_p (NOT (mask (LENGTH('i) - len)))) \<longleftrightarrow>
            (pfxm_p = NOT (mask (LENGTH('i) - len)) AND a)" for a::"'i::len word" and pfxm_p
     apply(subst ipset_from_cidr_alt2[symmetric])
     apply(subst zero_base_lsb_imp_set_eq_as_bit_operation)
      apply(simp; fail)
     apply(subst ipset_from_cidr_base_wellforemd)
      apply(simp; fail)
     apply(simp)
     done
     from 2[OF 1, of _ base] have
       "(x \<in> ipset_from_netmask base (~~ (mask (LENGTH('i) - len)))) \<longleftrightarrow>
        (base && ~~ (mask (LENGTH('i) - len)) = x && ~~ (mask (LENGTH('i) - len)))" for x
     apply(simp add: ipset_from_netmask_base_mask_consume)
     unfolding word_bw_comms(1)[of _ " ~~ (mask (LENGTH('i) - len))"] by simp
     then show ?thesis
       unfolding ip_cidr_set_def ipset_from_cidr_def
       by(auto simp add:  maskshift_eq_not_mask_generic)
   qed
 
   lemma ip_cidr_set_change_base: "j \<in> ip_cidr_set i r \<Longrightarrow> ip_cidr_set j r = ip_cidr_set i r"
     by (auto simp: ip_cidr_set_def)
 
 
 
 subsection\<open>IP Addresses as WordIntervals\<close>
   text\<open>The nice thing is: @{typ "'i wordinterval"}s are executable.\<close>
 
   definition iprange_single :: "'i::len word \<Rightarrow> 'i wordinterval" where
     "iprange_single ip \<equiv> WordInterval ip ip"
 
   fun iprange_interval :: "('i::len word \<times> 'i::len word) \<Rightarrow> 'i wordinterval" where
     "iprange_interval (ip_start, ip_end) = WordInterval ip_start ip_end"
   declare iprange_interval.simps[simp del]
 
   lemma iprange_interval_uncurry: "iprange_interval ipcidr = uncurry WordInterval ipcidr"
     by(cases ipcidr) (simp add: iprange_interval.simps)
 
   lemma "wordinterval_to_set (iprange_single ip) = {ip}"
     by(simp add: iprange_single_def)
   lemma "wordinterval_to_set (iprange_interval (ip1, ip2)) = {ip1 .. ip2}"
     by(simp add: iprange_interval.simps)
 
   text\<open>Now we can use the set operations on @{typ "'i::len wordinterval"}s\<close>
   term wordinterval_to_set
   term wordinterval_element
   term wordinterval_union
   term wordinterval_empty
   term wordinterval_setminus
   term wordinterval_UNIV
   term wordinterval_invert
   term wordinterval_intersection
   term wordinterval_subset
   term wordinterval_eq
 
 
 subsection\<open>IP Addresses in CIDR Notation\<close>
   text\<open>We want to convert IP addresses in CIDR notation to intervals.
     We already have @{const ipset_from_cidr}, which gives back a non-executable set.
     We want to convert to something we can store in an @{typ "'i wordinterval"}.\<close>
 
   fun ipcidr_to_interval_start :: "('i::len word \<times> nat) \<Rightarrow> 'i::len word" where
     "ipcidr_to_interval_start (pre, len) = (
       let netmask = (mask len) << (LENGTH('i) - len);
           network_prefix = (pre AND netmask)
       in network_prefix)"
   fun ipcidr_to_interval_end :: "('i::len word \<times> nat) \<Rightarrow> 'i::len word" where
     "ipcidr_to_interval_end (pre, len) = (
       let netmask = (mask len) << (LENGTH('i) - len);
           network_prefix = (pre AND netmask)
       in network_prefix OR (NOT netmask))"
   definition ipcidr_to_interval :: "('i::len word \<times> nat) \<Rightarrow> ('i word \<times> 'i word)" where
     "ipcidr_to_interval cidr \<equiv> (ipcidr_to_interval_start cidr, ipcidr_to_interval_end cidr)"
 
 
   lemma ipset_from_cidr_ipcidr_to_interval:
     "ipset_from_cidr base len =
       {ipcidr_to_interval_start (base,len) .. ipcidr_to_interval_end (base,len)}"
     by(simp add: Let_def ipcidr_to_interval_def ipset_from_cidr_def ipset_from_netmask_def)
   declare ipcidr_to_interval_start.simps[simp del] ipcidr_to_interval_end.simps[simp del]
 
   lemma ipcidr_to_interval:
     "ipcidr_to_interval (base, len) = (s,e) \<Longrightarrow> ipset_from_cidr base len = {s .. e}"
     by (simp add: ipcidr_to_interval_def ipset_from_cidr_ipcidr_to_interval)
 
   definition ipcidr_tuple_to_wordinterval :: "('i::len word \<times> nat) \<Rightarrow> 'i wordinterval" where
     "ipcidr_tuple_to_wordinterval iprng \<equiv> iprange_interval (ipcidr_to_interval iprng)"
 
   lemma wordinterval_to_set_ipcidr_tuple_to_wordinterval:
     "wordinterval_to_set (ipcidr_tuple_to_wordinterval (b, m)) = ipset_from_cidr b m"
     unfolding ipcidr_tuple_to_wordinterval_def ipset_from_cidr_ipcidr_to_interval
               ipcidr_to_interval_def
     by(simp add: iprange_interval.simps)
 
   lemma wordinterval_to_set_ipcidr_tuple_to_wordinterval_uncurry:
     "wordinterval_to_set (ipcidr_tuple_to_wordinterval ipcidr) = uncurry ipset_from_cidr ipcidr"
     by(cases ipcidr, simp add: wordinterval_to_set_ipcidr_tuple_to_wordinterval)
 
   definition ipcidr_union_set :: "('i::len word \<times> nat) set \<Rightarrow> ('i word) set" where
     "ipcidr_union_set ips \<equiv> \<Union>(base, len) \<in> ips. ipset_from_cidr base len"
 
   lemma ipcidr_union_set_uncurry:
     "ipcidr_union_set ips = (\<Union> ipcidr \<in> ips. uncurry ipset_from_cidr ipcidr)"
     by(simp add: ipcidr_union_set_def uncurry_case_stmt)
 
 
 subsection\<open>Clever Operations on IP Addresses in CIDR Notation\<close>
   text\<open>Intersecting two intervals may result in a new interval.
     Example: \<open>{1..10} \<inter> {5..20} = {5..10}\<close>
 
     Intersecting two IP address ranges represented as CIDR ranges results either in the empty set
     or the smaller of the two ranges. It will never create a new range.
     \<close>
   context
   begin
     (*contributed by Lars Noschinski*)
     private lemma less_and_not_mask_eq:
       fixes i :: "('a :: len) word"
       assumes "r2 \<le> r1" "i && ~~ (mask r2) = x && ~~ (mask r2)"
       shows "i && ~~ (mask r1) = x && ~~ (mask r1)"
     proof -
       have "i AND NOT (mask r1) = (i && ~~ (mask r2)) && ~~ (mask r1)" (is "_ = ?w && _")
         using \<open>r2 \<le> r1\<close> by (simp add: and_not_mask_twice max_def)
       also have "?w = x && ~~ (mask r2)" by fact
       also have "\<dots> && ~~ (mask r1) = x && ~~ (mask r1)"
         using \<open>r2 \<le> r1\<close> by (simp add: and_not_mask_twice max_def)
       finally show ?thesis .
     qed
 
     lemma ip_cidr_set_less:
       fixes i :: "'i::len word"
       shows "r1 \<le> r2 \<Longrightarrow> ip_cidr_set i r2 \<subseteq> ip_cidr_set i r1"
       unfolding ip_cidr_set_def
       apply auto
       apply (rule less_and_not_mask_eq[where ?r2.0="LENGTH('i) - r2"])
       apply auto
       done
 
     private lemma ip_cidr_set_intersect_subset_helper:
       fixes i1 r1 i2 r2
       assumes disj: "ip_cidr_set i1 r1 \<inter> ip_cidr_set i2 r2 \<noteq> {}" and  "r1 \<le> r2"
       shows "ip_cidr_set i2 r2 \<subseteq> ip_cidr_set i1 r1"
       proof -
       from disj obtain j where "j \<in> ip_cidr_set i1 r1" "j \<in> ip_cidr_set i2 r2" by auto
       with \<open>r1 \<le> r2\<close> have "j \<in> ip_cidr_set j r1" "j \<in> ip_cidr_set j r1"
         using ip_cidr_set_change_base ip_cidr_set_less by blast+
 
       show "ip_cidr_set i2 r2 \<subseteq> ip_cidr_set i1 r1"
       proof
         fix i assume "i \<in> ip_cidr_set i2 r2"
         with \<open>j \<in> ip_cidr_set i2 r2\<close> have "i \<in> ip_cidr_set j r2" using ip_cidr_set_change_base by auto
         also have "ip_cidr_set j r2 \<subseteq> ip_cidr_set j r1" using \<open>r1 \<le> r2\<close> ip_cidr_set_less by blast
         also have "\<dots> = ip_cidr_set i1 r1" using \<open>j \<in> ip_cidr_set i1 r1\<close> ip_cidr_set_change_base by blast
         finally show "i \<in> ip_cidr_set i1 r1" .
       qed
     qed
 
     lemma ip_cidr_set_notsubset_empty_inter:
       "\<not> ip_cidr_set i1 r1 \<subseteq> ip_cidr_set i2 r2 \<Longrightarrow>
        \<not> ip_cidr_set i2 r2 \<subseteq> ip_cidr_set i1 r1 \<Longrightarrow>
        ip_cidr_set i1 r1 \<inter> ip_cidr_set i2 r2 = {}"
       apply(cases "r1 \<le> r2")
        subgoal using ip_cidr_set_intersect_subset_helper by blast
       apply(cases "r2 \<le> r1")
        subgoal using ip_cidr_set_intersect_subset_helper by blast
       by(simp)
   end
 
 
   lemma ip_cidr_intersect:
      "\<not> ipset_from_cidr b2 m2 \<subseteq> ipset_from_cidr b1 m1 \<Longrightarrow>
       \<not> ipset_from_cidr b1 m1 \<subseteq> ipset_from_cidr b2 m2 \<Longrightarrow>
       ipset_from_cidr b1 m1 \<inter> ipset_from_cidr b2 m2 = {}"
     apply(simp add: ipset_from_cidr_eq_ip_cidr_set)
     using ip_cidr_set_notsubset_empty_inter by blast
 
   text\<open>Computing the intersection of two IP address ranges in CIDR notation\<close>
   fun ipcidr_conjunct :: "('i::len word \<times> nat) \<Rightarrow> ('i word \<times> nat) \<Rightarrow> ('i word \<times> nat) option" where
     "ipcidr_conjunct (base1, m1) (base2, m2) = (
        if
          ipset_from_cidr base1 m1 \<inter> ipset_from_cidr base2 m2 = {}
        then
          None
        else if
          ipset_from_cidr base1 m1 \<subseteq> ipset_from_cidr base2 m2
        then
          Some (base1, m1)
        else
          Some (base2, m2)
       )"
 
   text\<open>Intersecting with an address with prefix length zero always yields a non-empty result.\<close>
   lemma ipcidr_conjunct_any: "ipcidr_conjunct a (x,0) \<noteq> None" "ipcidr_conjunct (y,0) b \<noteq> None"
      apply(cases a, simp add: ipset_from_cidr_0 ipset_from_cidr_not_empty)
     by(cases b, simp add: ipset_from_cidr_0 ipset_from_cidr_not_empty)
 
   lemma ipcidr_conjunct_correct: "(case ipcidr_conjunct (b1, m1) (b2, m2)
                                           of Some (bx, mx) \<Rightarrow> ipset_from_cidr bx mx
                                           |  None \<Rightarrow> {}) =
                                    (ipset_from_cidr b1 m1) \<inter> (ipset_from_cidr b2 m2)"
     apply(simp split: if_split_asm)
     using ip_cidr_intersect by fast
   declare ipcidr_conjunct.simps[simp del]
 
 
 subsection\<open>Code Equations\<close>
   text\<open>Executable definition using word intervals\<close>
   lemma ipcidr_conjunct_word[code_unfold]:
   "ipcidr_conjunct ips1 ips2 = (
      if
       wordinterval_empty (wordinterval_intersection
                             (ipcidr_tuple_to_wordinterval ips1) (ipcidr_tuple_to_wordinterval ips2))
      then
        None
      else if
        wordinterval_subset (ipcidr_tuple_to_wordinterval ips1) (ipcidr_tuple_to_wordinterval ips2)
      then
        Some ips1
      else
        Some ips2
      )"
   apply(simp)
   apply(cases ips1, cases ips2, rename_tac b1 m1 b2 m2, simp)
   apply(auto simp add: wordinterval_to_set_ipcidr_tuple_to_wordinterval ipcidr_conjunct.simps
              split: if_split_asm)
   done
 
   (*with the code_unfold lemma before, this works!*)
   lemma "ipcidr_conjunct (0::32 word,0) (8,1) = Some (8, 1)" by eval
   export_code ipcidr_conjunct checking SML
 
   text\<open>making element check executable\<close>
   lemma addr_in_ipset_from_netmask_code[code_unfold]:
     "addr \<in> (ipset_from_netmask base netmask) \<longleftrightarrow>
       (base AND netmask) \<le> addr \<and> addr \<le> (base AND netmask) OR (NOT netmask)"
     by(simp add: ipset_from_netmask_def Let_def)
   lemma addr_in_ipset_from_cidr_code[code_unfold]:
     "(addr::'i::len word) \<in> (ipset_from_cidr pre len) \<longleftrightarrow>
        (pre AND ((mask len) << (LENGTH('i) - len))) \<le> addr \<and>
         addr \<le> pre OR (mask (LENGTH('i) - len))"
   unfolding ipset_from_cidr_alt by simp
 
   end
 
 end
diff --git a/thys/IP_Addresses/IPv4.thy b/thys/IP_Addresses/IPv4.thy
--- a/thys/IP_Addresses/IPv4.thy
+++ b/thys/IP_Addresses/IPv4.thy
@@ -1,267 +1,270 @@
 (*  Title:      IPv4.thy
     Authors:    Cornelius Diekmann, Julius Michaelis
 *)
 theory IPv4
 imports IP_Address
         NumberWang_IPv4
         (* include "HOL-Library.Code_Target_Nat" if you need to work with actual numbers.*)
 begin
 
-lemma take_bit_word_beyond_length_eq:
-  \<open>take_bit n w = w\<close> if \<open>LENGTH('a) \<le> n\<close> for w :: \<open>'a::len word\<close>
-  using that by transfer simp
-
-
 section \<open>IPv4 Adresses\<close>
   text\<open>An IPv4 address is basically a 32 bit unsigned integer.\<close>
   type_synonym ipv4addr = "32 word"
 
+  lemma ipv4addr_and_mask_eq_self [simp]:
+    \<open>a && 4294967295 = a\<close> for a :: ipv4addr
+  proof -
+    have \<open>take_bit 32 a = a\<close>
+      by (rule take_bit_word_eq_self) simp
+    then show ?thesis
+      by (simp add: take_bit_eq_mask mask_numeral)
+  qed
+
   text\<open>Conversion between natural numbers and IPv4 adresses\<close>
   definition nat_of_ipv4addr :: "ipv4addr \<Rightarrow> nat" where
     "nat_of_ipv4addr a = unat a"
   definition ipv4addr_of_nat :: "nat \<Rightarrow> ipv4addr" where
     "ipv4addr_of_nat n =  of_nat n"
 
   text\<open>The maximum IPv4 addres\<close>
   definition max_ipv4_addr :: "ipv4addr" where
     "max_ipv4_addr \<equiv> ipv4addr_of_nat ((2^32) - 1)"
 
   lemma max_ipv4_addr_number: "max_ipv4_addr = 4294967295"
     unfolding max_ipv4_addr_def ipv4addr_of_nat_def by(simp)
   lemma "max_ipv4_addr = 0b11111111111111111111111111111111"
     by(fact max_ipv4_addr_number)
   lemma max_ipv4_addr_max_word: "max_ipv4_addr = - 1"
     by(simp add: max_ipv4_addr_number)
   lemma max_ipv4_addr_max[simp]: "\<forall>a. a \<le> max_ipv4_addr"
     by(simp add: max_ipv4_addr_max_word)
   lemma UNIV_ipv4addrset: "UNIV = {0 .. max_ipv4_addr}" (*not in the simp set, for a reason*)
     by(simp add: max_ipv4_addr_max_word) fastforce
 
   text\<open>identity functions\<close>
   lemma nat_of_ipv4addr_ipv4addr_of_nat_mod: "nat_of_ipv4addr (ipv4addr_of_nat n) = n mod 2^32"
     by (simp add: ipv4addr_of_nat_def nat_of_ipv4addr_def unat_of_nat take_bit_eq_mod)
   lemma nat_of_ipv4addr_ipv4addr_of_nat:
     "\<lbrakk> n \<le> nat_of_ipv4addr max_ipv4_addr \<rbrakk> \<Longrightarrow> nat_of_ipv4addr (ipv4addr_of_nat n) = n"
     by (simp add: nat_of_ipv4addr_ipv4addr_of_nat_mod max_ipv4_addr_def)
   lemma ipv4addr_of_nat_nat_of_ipv4addr: "ipv4addr_of_nat (nat_of_ipv4addr addr) = addr"
     by(simp add: ipv4addr_of_nat_def nat_of_ipv4addr_def)
 
   subsection\<open>Representing IPv4 Adresses (Syntax)\<close>
 
   context
     includes bit_operations_syntax
   begin
 
   fun ipv4addr_of_dotdecimal :: "nat \<times> nat \<times> nat \<times> nat \<Rightarrow> ipv4addr" where
     "ipv4addr_of_dotdecimal (a,b,c,d) = ipv4addr_of_nat (d + 256 * c + 65536 * b + 16777216 * a )"
 
   fun dotdecimal_of_ipv4addr :: "ipv4addr \<Rightarrow> nat \<times> nat \<times> nat \<times> nat" where
     "dotdecimal_of_ipv4addr a = (nat_of_ipv4addr ((a >> 24) AND 0xFF),
                                     nat_of_ipv4addr ((a >> 16) AND 0xFF),
                                     nat_of_ipv4addr ((a >> 8) AND 0xFF),
                                     nat_of_ipv4addr (a AND 0xff))"
 
   declare ipv4addr_of_dotdecimal.simps[simp del]
   declare dotdecimal_of_ipv4addr.simps[simp del]
 
   text\<open>Examples:\<close>
   lemma "ipv4addr_of_dotdecimal (192, 168, 0, 1) = 3232235521"
     by(simp add: ipv4addr_of_dotdecimal.simps ipv4addr_of_nat_def)
     (*could be solved by eval, but needs "HOL-Library.Code_Target_Nat"*)
   lemma "dotdecimal_of_ipv4addr 3232235521 = (192, 168, 0, 1)"
     by(simp add: dotdecimal_of_ipv4addr.simps nat_of_ipv4addr_def)
 
   text\<open>a different notation for @{term ipv4addr_of_dotdecimal}\<close>
   lemma ipv4addr_of_dotdecimal_bit:
     "ipv4addr_of_dotdecimal (a,b,c,d) =
       (ipv4addr_of_nat a << 24) + (ipv4addr_of_nat b << 16) +
        (ipv4addr_of_nat c << 8) + ipv4addr_of_nat d"
   proof -
     have a: "(ipv4addr_of_nat a) << 24 = ipv4addr_of_nat (a * 16777216)"
       by(simp add: ipv4addr_of_nat_def shiftl_t2n)
     have b: "(ipv4addr_of_nat b) << 16 = ipv4addr_of_nat (b * 65536)"
       by(simp add: ipv4addr_of_nat_def shiftl_t2n)
     have c: "(ipv4addr_of_nat c) << 8 = ipv4addr_of_nat (c * 256)"
       by(simp add: ipv4addr_of_nat_def shiftl_t2n)
     have ipv4addr_of_nat_suc: "\<And>x. ipv4addr_of_nat (Suc x) = word_succ (ipv4addr_of_nat (x))"
       by(simp add: ipv4addr_of_nat_def, metis Abs_fnat_hom_Suc of_nat_Suc)
     { fix x y
       have "ipv4addr_of_nat x + ipv4addr_of_nat y = ipv4addr_of_nat (x+y)"
         apply(induction x arbitrary: y)
          apply(simp add: ipv4addr_of_nat_def; fail)
         by(simp add: ipv4addr_of_nat_suc word_succ_p1)
     } from this a b c
     show ?thesis
       apply(simp add: ipv4addr_of_dotdecimal.simps)
       apply(rule arg_cong[where f=ipv4addr_of_nat])
       apply(thin_tac _)+
       by presburger
   qed
 
   lemma size_ipv4addr: "size (x::ipv4addr) = 32" by(simp add:word_size)
 
   lemma dotdecimal_of_ipv4addr_ipv4addr_of_dotdecimal:
   "\<lbrakk> a < 256; b < 256; c < 256; d < 256 \<rbrakk> \<Longrightarrow>
     dotdecimal_of_ipv4addr (ipv4addr_of_dotdecimal (a,b,c,d)) = (a,b,c,d)"
   proof -
     assume  "a < 256" and "b < 256" and "c < 256" and "d < 256"
     note assms= \<open>a < 256\<close> \<open>b < 256\<close> \<open>c < 256\<close> \<open>d < 256\<close>
     hence a:  "nat_of_ipv4addr ((ipv4addr_of_nat (d + 256 * c + 65536 * b + 16777216 * a) >> 24) AND mask 8) = a"
+      apply (simp only: flip: take_bit_eq_mask)
       apply (simp add: ipv4addr_of_nat_def nat_of_ipv4addr_def)
       apply transfer
       apply (simp add: drop_bit_take_bit nat_take_bit_eq flip: take_bit_eq_mask)
       apply (simp add: drop_bit_eq_div take_bit_eq_mod)
       done
     have ipv4addr_of_nat_AND_mask8: "(ipv4addr_of_nat a) AND mask 8 = (ipv4addr_of_nat (a mod 256))"
       for a
+      apply (simp only: flip: take_bit_eq_mask)
       apply (simp add: ipv4addr_of_nat_def)
       apply transfer
       apply (simp flip: take_bit_eq_mask)
       apply (simp add: take_bit_eq_mod of_nat_mod)
       done
     from assms have b:
       "nat_of_ipv4addr ((ipv4addr_of_nat (d + 256 * c + 65536 * b + 16777216 * a) >> 16) AND mask 8) = b"
+      apply (simp only: flip: take_bit_eq_mask)
       apply (simp add: ipv4addr_of_nat_def nat_of_ipv4addr_def)
       apply transfer
       apply (simp add: drop_bit_take_bit flip: take_bit_eq_mask)
       using div65536
       apply (simp add: drop_bit_eq_div take_bit_eq_mod)
       done
     from assms have c:
       "nat_of_ipv4addr ((ipv4addr_of_nat (d + 256 * c + 65536 * b + 16777216 * a) >> 8) AND mask 8) = c"
+      apply (simp only: flip: take_bit_eq_mask)
       apply (simp add: ipv4addr_of_nat_def nat_of_ipv4addr_def)
       apply transfer
       apply (simp add: drop_bit_take_bit flip: take_bit_eq_mask)
       using div256
       apply (simp add: drop_bit_eq_div take_bit_eq_mod)
       done
     from \<open>d < 256\<close> have d: "nat_of_ipv4addr (ipv4addr_of_nat (d + 256 * c + 65536 * b + 16777216 * a) AND mask 8) = d"
+      apply (simp only: flip: take_bit_eq_mask)
       apply (simp add: ipv4addr_of_nat_AND_mask8 ipv4addr_of_nat_def nat_of_ipv4addr_def)
       apply transfer
       apply (simp flip: take_bit_eq_mask)
       apply (simp add: take_bit_eq_mod nat_mod_distrib nat_add_distrib nat_mult_distrib mod256)
       done
     from a b c d show ?thesis
-      apply (simp add: ipv4addr_of_dotdecimal.simps dotdecimal_of_ipv4addr.simps)
-      apply (simp add: mask_eq push_bit_of_1)
+      apply (simp add: ipv4addr_of_dotdecimal.simps dotdecimal_of_ipv4addr.simps mask_numeral)
       done
   qed
 
   lemma ipv4addr_of_dotdecimal_dotdecimal_of_ipv4addr:
     "(ipv4addr_of_dotdecimal (dotdecimal_of_ipv4addr ip)) = ip"
   proof -
     have ip_and_mask8_bl_drop24: "(ip::ipv4addr) AND mask 8 = of_bl (drop 24 (to_bl ip))"
       by(simp add: of_drop_to_bl size_ipv4addr)
     have List_rev_drop_geqn: "length x \<ge> n \<Longrightarrow> (take n (rev x)) = rev (drop (length x - n) x)"
       for x :: "'a list" and n by(simp add: List.rev_drop)
     have and_mask_bl_take: "length x \<ge> n \<Longrightarrow> ((of_bl x) AND mask n) = (of_bl (rev (take n (rev (x)))))"
       for x n by(simp add: List_rev_drop_geqn of_bl_drop)
-    have ipv4addr_and_255: "x AND 255 = x AND mask 8" for x :: ipv4addr
-      by (simp add: mask_eq push_bit_of_1)
+    have ipv4addr_and_255: "x AND 255 = take_bit 8 x" for x :: ipv4addr
+      by (simp add: take_bit_eq_mask mask_numeral)
     have bit_equality:
       "((ip >> 24) AND 0xFF << 24) + ((ip >> 16) AND 0xFF << 16) + ((ip >> 8) AND 0xFF << 8) + (ip AND 0xFF) =
        of_bl (take 8 (to_bl ip) @ take 8 (drop 8 (to_bl ip)) @ take 8 (drop 16 (to_bl ip)) @ drop 24 (to_bl ip))"
-      apply(simp add: ipv4addr_and_255)
-      apply(simp add: shiftr_slice)
-      apply(simp add: slice_take' size_ipv4addr and_mask_bl_take flip: push_bit_and)
-      apply(simp add: List_rev_drop_geqn)
-      apply(simp add: drop_take)
-      apply(simp add: shiftl_of_bl)
-      apply(simp add: of_bl_append)
-      apply(simp add: ip_and_mask8_bl_drop24)
+      apply (simp add: ipv4addr_and_255 shiftl_def shiftr_def rev_drop rev_take drop_take)
+      apply (simp only: of_bl_append mult.commute [of \<open>2 ^ n\<close> for n] flip: push_bit_eq_mult)
+      apply (simp add: of_bl_drop_eq_take_bit take_drop of_bl_take_to_bl_eq_drop_bit take_bit_drop_bit take_bit_word_eq_self)
       done
     have blip_split: "\<And> blip. length blip = 32 \<Longrightarrow>
       blip = (take 8 blip) @ (take 8 (drop 8 blip)) @ (take 8 (drop 16 blip)) @ (take 8 (drop 24 blip))"
       by(rename_tac blip,case_tac blip,simp_all)+ (*I'm so sorry for this ...*)
     have "ipv4addr_of_dotdecimal (dotdecimal_of_ipv4addr ip) = of_bl (to_bl ip)"
       apply (subst blip_split)
        apply simp
       apply (simp add: ipv4addr_of_dotdecimal_bit dotdecimal_of_ipv4addr.simps)
       apply (simp add: ipv4addr_of_nat_nat_of_ipv4addr)
       apply (simp flip: bit_equality)
       done
     thus ?thesis using word_bl.Rep_inverse[symmetric] by simp
   qed
 
   lemma ipv4addr_of_dotdecimal_eqE:
     "\<lbrakk> ipv4addr_of_dotdecimal (a,b,c,d) = ipv4addr_of_dotdecimal (e,f,g,h);
        a < 256; b < 256; c < 256; d < 256; e < 256; f < 256; g < 256; h < 256 \<rbrakk> \<Longrightarrow>
          a = e \<and> b = f \<and> c = g \<and> d = h"
      by (metis Pair_inject dotdecimal_of_ipv4addr_ipv4addr_of_dotdecimal)
 
 subsection\<open>IP Ranges: Examples\<close>
   lemma "(UNIV :: ipv4addr set) = {0 .. max_ipv4_addr}" by(simp add: UNIV_ipv4addrset)
   lemma "(42::ipv4addr) \<in> UNIV" by(simp)
 
   (*Warning, not executable!*)
 
   lemma "ipset_from_netmask (ipv4addr_of_dotdecimal (192,168,0,42)) (ipv4addr_of_dotdecimal (255,255,0,0)) =
           {ipv4addr_of_dotdecimal (192,168,0,0) .. ipv4addr_of_dotdecimal (192,168,255,255)}"
    by(simp add: ipset_from_netmask_def ipv4addr_of_dotdecimal.simps ipv4addr_of_nat_def)
 
   lemma "ipset_from_netmask (ipv4addr_of_dotdecimal (192,168,0,42)) (ipv4addr_of_dotdecimal (0,0,0,0)) = UNIV"
     by(simp add: UNIV_ipv4addrset ipset_from_netmask_def ipv4addr_of_dotdecimal.simps
                  ipv4addr_of_nat_def max_ipv4_addr_max_word)
 
   text\<open>192.168.0.0/24\<close>
 
   lemma fixes addr :: ipv4addr
     shows "ipset_from_cidr addr pflength =
             ipset_from_netmask addr ((mask pflength) << (32 - pflength))"
     by(simp add: ipset_from_cidr_def)
 
   lemma "ipset_from_cidr (ipv4addr_of_dotdecimal (192,168,0,42)) 16 =
           {ipv4addr_of_dotdecimal (192,168,0,0) .. ipv4addr_of_dotdecimal (192,168,255,255)}"
-   by(simp add: ipset_from_cidr_alt mask_eq ipv4addr_of_dotdecimal.simps ipv4addr_of_nat_def push_bit_of_1)
+   by(simp add: ipset_from_cidr_alt mask_eq ipv4addr_of_dotdecimal.simps ipv4addr_of_nat_def)
 
   lemma "ip \<in> (ipset_from_cidr (ipv4addr_of_dotdecimal (0, 0, 0, 0)) 0)"
     by(simp add: ipset_from_cidr_0)
 
   lemma ipv4set_from_cidr_32: fixes addr :: ipv4addr
     shows "ipset_from_cidr addr 32 = {addr}"
-    by (simp add: ipset_from_cidr_alt take_bit_word_beyond_length_eq flip: take_bit_eq_mask)
+    by (simp add: ipset_from_cidr_alt mask_numeral)
 
-  lemma  fixes pre :: ipv4addr
+  lemma fixes pre :: ipv4addr
     shows "ipset_from_cidr pre len = {(pre AND ((mask len) << (32 - len))) .. pre OR (mask (32 - len))}"
     by (simp add: ipset_from_cidr_alt ipset_from_cidr_def)
 
   text\<open>making element check executable\<close>
   lemma addr_in_ipv4set_from_netmask_code[code_unfold]:
     fixes addr :: ipv4addr
     shows "addr \<in> (ipset_from_netmask base netmask) \<longleftrightarrow>
             (base AND netmask) \<le> addr \<and> addr \<le> (base AND netmask) OR (NOT netmask)"
     by (simp add: addr_in_ipset_from_netmask_code)
   lemma addr_in_ipv4set_from_cidr_code[code_unfold]:
     fixes addr :: ipv4addr
     shows "addr \<in> (ipset_from_cidr pre len) \<longleftrightarrow>
               (pre AND ((mask len) << (32 - len))) \<le> addr \<and> addr \<le> pre OR (mask (32 - len))"
     by(simp add: addr_in_ipset_from_cidr_code)
 
   (*small numbers because we didn't load Code_Target_Nat. Should work by eval*)
-lemma "ipv4addr_of_dotdecimal (192,168,42,8) \<in> (ipset_from_cidr (ipv4addr_of_dotdecimal (192,168,0,0)) 16)"
-  by (simp add: ipv4addr_of_nat_def ipset_from_cidr_def ipv4addr_of_dotdecimal.simps
-    ipset_from_netmask_def mask_eq_exp_minus_1 word_le_def take_bit_minus_one_eq_mask)
+  lemma "ipv4addr_of_dotdecimal (192,168,42,8) \<in> (ipset_from_cidr (ipv4addr_of_dotdecimal (192,168,0,0)) 16)"
+    by (simp add: ipv4addr_of_nat_def ipset_from_cidr_def ipv4addr_of_dotdecimal.simps
+      ipset_from_netmask_def mask_eq_exp_minus_1 word_le_def)
 
   definition ipv4range_UNIV :: "32 wordinterval" where "ipv4range_UNIV \<equiv> wordinterval_UNIV"
 
   lemma ipv4range_UNIV_set_eq: "wordinterval_to_set ipv4range_UNIV = UNIV"
     by(simp only: ipv4range_UNIV_def wordinterval_UNIV_set_eq)
 
 
   thm iffD1[OF wordinterval_eq_set_eq]
   (*TODO: probably the following is a good idea?*)
   (*
   declare iffD1[OF wordinterval_eq_set_eq, cong]
   *)
 
 
   text\<open>This \<open>LENGTH('a)\<close> is 32 for IPv4 addresses.\<close>
   lemma ipv4cidr_to_interval_simps[code_unfold]: "ipcidr_to_interval ((pre::ipv4addr), len) = (
       let netmask = (mask len) << (32 - len);
           network_prefix = (pre AND netmask)
       in (network_prefix, network_prefix OR (NOT netmask)))"
   by(simp add: ipcidr_to_interval_def Let_def ipcidr_to_interval_start.simps ipcidr_to_interval_end.simps)
 
   end
 
 end
diff --git a/thys/IP_Addresses/IPv6.thy b/thys/IP_Addresses/IPv6.thy
--- a/thys/IP_Addresses/IPv6.thy
+++ b/thys/IP_Addresses/IPv6.thy
@@ -1,964 +1,955 @@
 (*  Title:      IPv6.thy
     Authors:    Cornelius Diekmann
 *)
 theory IPv6
   imports
     IP_Address
     NumberWang_IPv6
     (* include "HOL-Library.Code_Target_Nat" if you need to work with actual numbers.*)
 begin
 
 section \<open>IPv6 Addresses\<close>
   text\<open>An IPv6 address is basically a 128 bit unsigned integer. RFC 4291, Section 2.\<close>
   type_synonym ipv6addr = "128 word"
  
   text\<open>Conversion between natural numbers and IPv6 adresses\<close>
   definition nat_of_ipv6addr :: "ipv6addr \<Rightarrow> nat" where
     "nat_of_ipv6addr a = unat a"
   definition ipv6addr_of_nat :: "nat \<Rightarrow> ipv6addr" where
     "ipv6addr_of_nat n =  of_nat n"
 
   lemma "ipv6addr_of_nat n = word_of_int (int n)"
     by(simp add: ipv6addr_of_nat_def)
 
   text\<open>The maximum IPv6 address\<close>
   definition max_ipv6_addr :: "ipv6addr" where 
     "max_ipv6_addr \<equiv> ipv6addr_of_nat ((2^128) - 1)"
 
   lemma max_ipv6_addr_number: "max_ipv6_addr = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
     unfolding max_ipv6_addr_def ipv6addr_of_nat_def by(simp)
   lemma "max_ipv6_addr = 340282366920938463463374607431768211455"
     by(fact max_ipv6_addr_number)
   lemma max_ipv6_addr_max_word: "max_ipv6_addr = - 1"
     by(simp add: max_ipv6_addr_number)
   lemma max_ipv6_addr_max: "\<forall>a. a \<le> max_ipv6_addr"
     by(simp add: max_ipv6_addr_max_word)
   lemma UNIV_ipv6addrset: "UNIV = {0 .. max_ipv6_addr}" (*not in the simp set, for a reason*)
     by(simp add: max_ipv6_addr_max_word) fastforce
 
   text\<open>identity functions\<close>
   lemma nat_of_ipv6addr_ipv6addr_of_nat_mod: "nat_of_ipv6addr (ipv6addr_of_nat n) = n mod 2^128"
     by (simp add: ipv6addr_of_nat_def nat_of_ipv6addr_def unat_of_nat take_bit_eq_mod)
   lemma nat_of_ipv6addr_ipv6addr_of_nat:
     "n \<le> nat_of_ipv6addr max_ipv6_addr \<Longrightarrow> nat_of_ipv6addr (ipv6addr_of_nat n) = n"
     by (simp add: nat_of_ipv6addr_ipv6addr_of_nat_mod max_ipv6_addr_def)
   lemma ipv6addr_of_nat_nat_of_ipv6addr: "ipv6addr_of_nat (nat_of_ipv6addr addr) = addr"
     by(simp add: ipv6addr_of_nat_def nat_of_ipv6addr_def)
 
   subsection\<open>Syntax of IPv6 Adresses\<close>
   text\<open>RFC 4291, Section 2.2.: Text Representation of Addresses\<close>
 
   text\<open>Quoting the RFC (note: errata exists):\<close>
   text_raw\<open>
   \begin{verbatim}
    1. The preferred form is x:x:x:x:x:x:x:x, where the 'x's are one to
       four hexadecimal digits of the eight 16-bit pieces of the address.
       Examples:
          ABCD:EF01:2345:6789:ABCD:EF01:2345:6789
          2001:DB8:0:0:8:800:200C:417A
   \end{verbatim}
 \<close>
   datatype ipv6addr_syntax = 
     IPv6AddrPreferred "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" "16 word"
 
   text_raw\<open>
   \begin{verbatim}
    2. [...] In order to make writing addresses containing zero
       bits easier, a special syntax is available to compress the zeros.
       The use of "::" indicates one or more groups of 16 bits of zeros.
       The "::" can only appear once in an address.  The "::" can also be
       used to compress leading or trailing zeros in an address.
 
       For example, the following addresses
          2001:DB8:0:0:8:800:200C:417A   a unicast address
          FF01:0:0:0:0:0:0:101           a multicast address
          0:0:0:0:0:0:0:1                the loopback address
          0:0:0:0:0:0:0:0                the unspecified address
 
       may be represented as
          2001:DB8::8:800:200C:417A      a unicast address
          FF01::101                      a multicast address
          ::1                            the loopback address
          ::                             the unspecified address
   \end{verbatim}
 \<close>
   (*datatype may take some minutes to load*)
   datatype ipv6addr_syntax_compressed =
   \<comment> \<open>using @{typ unit} for the omission @{text "::"}. 
 
      Naming convention of the datatype: 
       The first number is the position where the omission occurs.
       The second number is the length of the specified address pieces.
         I.e. `8 minus the second number' pieces are omitted.\<close>
     IPv6AddrCompressed1_0 unit
   | IPv6AddrCompressed1_1 unit "16 word"
   | IPv6AddrCompressed1_2 unit "16 word" "16 word"
   | IPv6AddrCompressed1_3 unit "16 word" "16 word" "16 word"
   | IPv6AddrCompressed1_4 unit "16 word" "16 word" "16 word" "16 word" 
   | IPv6AddrCompressed1_5 unit "16 word" "16 word" "16 word" "16 word" "16 word"
   | IPv6AddrCompressed1_6 unit "16 word" "16 word" "16 word" "16 word" "16 word" "16 word"
   | IPv6AddrCompressed1_7 unit "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" "16 word"
 
   | IPv6AddrCompressed2_1 "16 word" unit
   | IPv6AddrCompressed2_2 "16 word" unit "16 word"
   | IPv6AddrCompressed2_3 "16 word" unit "16 word" "16 word"
   | IPv6AddrCompressed2_4 "16 word" unit "16 word" "16 word" "16 word"
   | IPv6AddrCompressed2_5 "16 word" unit "16 word" "16 word" "16 word" "16 word"
   | IPv6AddrCompressed2_6 "16 word" unit "16 word" "16 word" "16 word" "16 word" "16 word"
   | IPv6AddrCompressed2_7 "16 word" unit "16 word" "16 word" "16 word" "16 word" "16 word" "16 word"
 
   | IPv6AddrCompressed3_2 "16 word" "16 word" unit
   | IPv6AddrCompressed3_3 "16 word" "16 word" unit "16 word"
   | IPv6AddrCompressed3_4 "16 word" "16 word" unit "16 word" "16 word"
   | IPv6AddrCompressed3_5 "16 word" "16 word" unit "16 word" "16 word" "16 word"
   | IPv6AddrCompressed3_6 "16 word" "16 word" unit "16 word" "16 word" "16 word" "16 word"
   | IPv6AddrCompressed3_7 "16 word" "16 word" unit "16 word" "16 word" "16 word" "16 word" "16 word"
 
   | IPv6AddrCompressed4_3 "16 word" "16 word" "16 word" unit
   | IPv6AddrCompressed4_4 "16 word" "16 word" "16 word" unit "16 word"
   | IPv6AddrCompressed4_5 "16 word" "16 word" "16 word" unit "16 word" "16 word"
   | IPv6AddrCompressed4_6 "16 word" "16 word" "16 word" unit "16 word" "16 word" "16 word"
   | IPv6AddrCompressed4_7 "16 word" "16 word" "16 word" unit "16 word" "16 word" "16 word" "16 word"
 
   | IPv6AddrCompressed5_4 "16 word" "16 word" "16 word" "16 word" unit
   | IPv6AddrCompressed5_5 "16 word" "16 word" "16 word" "16 word" unit "16 word"
   | IPv6AddrCompressed5_6 "16 word" "16 word" "16 word" "16 word" unit "16 word" "16 word"
   | IPv6AddrCompressed5_7 "16 word" "16 word" "16 word" "16 word" unit "16 word" "16 word" "16 word"
 
   | IPv6AddrCompressed6_5 "16 word" "16 word" "16 word" "16 word" "16 word" unit
   | IPv6AddrCompressed6_6 "16 word" "16 word" "16 word" "16 word" "16 word" unit "16 word"
   | IPv6AddrCompressed6_7 "16 word" "16 word" "16 word" "16 word" "16 word" unit "16 word" "16 word"
 
   | IPv6AddrCompressed7_6 "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" unit
   | IPv6AddrCompressed7_7 "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" unit "16 word"
 
   | IPv6AddrCompressed8_7 "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" "16 word" unit
 
   (*RFC 5952:
     """
     4.  A Recommendation for IPv6 Text Representation
     4.2.2.  Handling One 16-Bit 0 Field
        The symbol "::" MUST NOT be used to shorten just one 16-bit 0 field.
        For example, the representation 2001:db8:0:1:1:1:1:1 is correct, but
        2001:db8::1:1:1:1:1 is not correct.
     """
 
     So we could remove all IPv6AddrCompressed*_7 constructors.
     But these are `recommendations', we might still see these non-recommended definitions.
     "[...] all implementations must accept and be able to handle any legitimate RFC 4291 format."
   *)
 
   (*More convenient parser helper function for compressed IPv6 addresses:
     Input list (from parser):
       Some 16word \<longrightarrow> address piece
       None \<longrightarrow> omission '::'
     
   
    Basically, the parser must only do the following (python syntax):
      split the string which is an ipv6 address at ':'
      map empty string to None
      map everything else to Some (string_to_16word str)
      sanitize empty strings at the start and the end (see toString and parser theories)
    Example:
      "1:2:3".split(":")  = ['1', '2', '3']
      ":2:3:4".split(":") = ['', '2', '3', '4']
      ":2::3".split(":")  = ['', '2', '', '3']
      "1:2:3:".split(":") = ['1', '2', '3', '']
   *)
   definition parse_ipv6_address_compressed :: "((16 word) option) list \<Rightarrow> ipv6addr_syntax_compressed option" where
     "parse_ipv6_address_compressed as = (case as of 
       [None] \<Rightarrow> Some (IPv6AddrCompressed1_0 ())
     | [None, Some a] \<Rightarrow> Some (IPv6AddrCompressed1_1 () a)
     | [None, Some a, Some b] \<Rightarrow> Some (IPv6AddrCompressed1_2 () a b)
     | [None, Some a, Some b, Some c] \<Rightarrow> Some (IPv6AddrCompressed1_3 () a b c)
     | [None, Some a, Some b, Some c, Some d] \<Rightarrow> Some (IPv6AddrCompressed1_4 () a b c d)
     | [None, Some a, Some b, Some c, Some d, Some e] \<Rightarrow> Some (IPv6AddrCompressed1_5 () a b c d e)
     | [None, Some a, Some b, Some c, Some d, Some e, Some f] \<Rightarrow> Some (IPv6AddrCompressed1_6 () a b c d e f)
     | [None, Some a, Some b, Some c, Some d, Some e, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed1_7 () a b c d e f g)
   
     | [Some a, None] \<Rightarrow> Some (IPv6AddrCompressed2_1 a ())
     | [Some a, None, Some b] \<Rightarrow> Some (IPv6AddrCompressed2_2 a () b)
     | [Some a, None, Some b, Some c] \<Rightarrow> Some (IPv6AddrCompressed2_3 a () b c)
     | [Some a, None, Some b, Some c, Some d] \<Rightarrow> Some (IPv6AddrCompressed2_4 a () b c d)
     | [Some a, None, Some b, Some c, Some d, Some e] \<Rightarrow> Some (IPv6AddrCompressed2_5 a () b c d e)
     | [Some a, None, Some b, Some c, Some d, Some e, Some f] \<Rightarrow> Some (IPv6AddrCompressed2_6 a () b c d e f)
     | [Some a, None, Some b, Some c, Some d, Some e, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed2_7 a () b c d e f g)
   
     | [Some a, Some b, None] \<Rightarrow> Some (IPv6AddrCompressed3_2 a b ())
     | [Some a, Some b, None, Some c] \<Rightarrow> Some (IPv6AddrCompressed3_3 a b () c)
     | [Some a, Some b, None, Some c, Some d] \<Rightarrow> Some (IPv6AddrCompressed3_4 a b () c d)
     | [Some a, Some b, None, Some c, Some d, Some e] \<Rightarrow> Some (IPv6AddrCompressed3_5 a b () c d e)
     | [Some a, Some b, None, Some c, Some d, Some e, Some f] \<Rightarrow> Some (IPv6AddrCompressed3_6 a b () c d e f)
     | [Some a, Some b, None, Some c, Some d, Some e, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed3_7 a b () c d e f g)
   
     | [Some a, Some b, Some c, None] \<Rightarrow> Some (IPv6AddrCompressed4_3 a b c ())
     | [Some a, Some b, Some c, None, Some d] \<Rightarrow> Some (IPv6AddrCompressed4_4 a b c () d)
     | [Some a, Some b, Some c, None, Some d, Some e] \<Rightarrow> Some (IPv6AddrCompressed4_5 a b c () d e)
     | [Some a, Some b, Some c, None, Some d, Some e, Some f] \<Rightarrow> Some (IPv6AddrCompressed4_6 a b c () d e f)
     | [Some a, Some b, Some c, None, Some d, Some e, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed4_7 a b c () d e f g)
   
     | [Some a, Some b, Some c, Some d, None] \<Rightarrow> Some (IPv6AddrCompressed5_4 a b c d ())
     | [Some a, Some b, Some c, Some d, None, Some e] \<Rightarrow> Some (IPv6AddrCompressed5_5 a b c d () e)
     | [Some a, Some b, Some c, Some d, None, Some e, Some f] \<Rightarrow> Some (IPv6AddrCompressed5_6 a b c d () e f)
     | [Some a, Some b, Some c, Some d, None, Some e, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed5_7 a b c d () e f g)
   
     | [Some a, Some b, Some c, Some d, Some e, None] \<Rightarrow> Some (IPv6AddrCompressed6_5 a b c d e ())
     | [Some a, Some b, Some c, Some d, Some e, None, Some f] \<Rightarrow> Some (IPv6AddrCompressed6_6 a b c d e () f)
     | [Some a, Some b, Some c, Some d, Some e, None, Some f, Some g] \<Rightarrow> Some (IPv6AddrCompressed6_7 a b c d e () f g)
   
     | [Some a, Some b, Some c, Some d, Some e, Some f, None] \<Rightarrow> Some (IPv6AddrCompressed7_6 a b c d e f ())
     | [Some a, Some b, Some c, Some d, Some e, Some f, None, Some g] \<Rightarrow> Some (IPv6AddrCompressed7_7 a b c d e f () g)
 
     | [Some a, Some b, Some c, Some d, Some e, Some f, Some g, None] \<Rightarrow> Some (IPv6AddrCompressed8_7 a b c d e f g ())
     | _ \<Rightarrow> None \<comment> \<open>invalid ipv6 copressed address.\<close>
 )"
 
   fun ipv6addr_syntax_compressed_to_list :: "ipv6addr_syntax_compressed \<Rightarrow> ((16 word) option) list"
     where 
       "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_0 _) =
                                      [None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_1 () a) =
                                      [None, Some a]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_2 () a b) =
                                      [None, Some a, Some b]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_3 () a b c) =
                                      [None, Some a, Some b, Some c]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_4 () a b c d) =
                                      [None, Some a, Some b, Some c, Some d]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_5 () a b c d e) =
                                      [None, Some a, Some b, Some c, Some d, Some e]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_6 () a b c d e f) =
                                      [None, Some a, Some b, Some c, Some d, Some e, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed1_7 () a b c d e f g) =
                                      [None, Some a, Some b, Some c, Some d, Some e, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_1 a ()) =
                                      [Some a, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_2 a () b) =
                                      [Some a, None, Some b]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_3 a () b c) =
                                      [Some a, None, Some b, Some c]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_4 a () b c d) =
                                      [Some a, None, Some b, Some c, Some d]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_5 a () b c d e) =
                                      [Some a, None, Some b, Some c, Some d, Some e]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_6 a () b c d e f) =
                                      [Some a, None, Some b, Some c, Some d, Some e, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed2_7 a () b c d e f g) =
                                      [Some a, None, Some b, Some c, Some d, Some e, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_2 a b ()) = [Some a, Some b, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_3 a b () c) =
                                      [Some a, Some b, None, Some c]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_4 a b () c d) =
                                      [Some a, Some b, None, Some c, Some d]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_5 a b () c d e) =
                                      [Some a, Some b, None, Some c, Some d, Some e]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_6 a b () c d e f) =
                                      [Some a, Some b, None, Some c, Some d, Some e, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed3_7 a b () c d e f g) =
                                      [Some a, Some b, None, Some c, Some d, Some e, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed4_3 a b c ()) =
                                      [Some a, Some b, Some c, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed4_4 a b c () d) =
                                      [Some a, Some b, Some c, None, Some d]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed4_5 a b c () d e) =
                                      [Some a, Some b, Some c, None, Some d, Some e]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed4_6 a b c () d e f) =
                                      [Some a, Some b, Some c, None, Some d, Some e, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed4_7 a b c () d e f g) =
                                      [Some a, Some b, Some c, None, Some d, Some e, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed5_4 a b c d ()) =
                                      [Some a, Some b, Some c, Some d, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed5_5 a b c d () e) =
                                      [Some a, Some b, Some c, Some d, None, Some e]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed5_6 a b c d () e f) =
                                      [Some a, Some b, Some c, Some d, None, Some e, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed5_7 a b c d () e f g) =
                                      [Some a, Some b, Some c, Some d, None, Some e, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed6_5 a b c d e ()) =
                                      [Some a, Some b, Some c, Some d, Some e, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed6_6 a b c d e () f) =
                                      [Some a, Some b, Some c, Some d, Some e, None, Some f]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed6_7 a b c d e () f g) =
                                      [Some a, Some b, Some c, Some d, Some e, None, Some f, Some g]"
   
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed7_6 a b c d e f ()) =
                                      [Some a, Some b, Some c, Some d, Some e, Some f, None]"
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed7_7 a b c d e f () g) =
                                      [Some a, Some b, Some c, Some d, Some e, Some f, None, Some g]"
 
     | "ipv6addr_syntax_compressed_to_list (IPv6AddrCompressed8_7 a b c d e f g ()) =
                                      [Some a, Some b, Some c, Some d, Some e, Some f, Some g, None]"
 
 
 (*for all ipv6_syntax, there is a corresponding list representation*)
 lemma parse_ipv6_address_compressed_exists:
   obtains ss where "parse_ipv6_address_compressed ss = Some ipv6_syntax"
 proof
   define ss where "ss = ipv6addr_syntax_compressed_to_list ipv6_syntax"
   thus "parse_ipv6_address_compressed ss = Some ipv6_syntax"
     by (cases ipv6_syntax; simp add: parse_ipv6_address_compressed_def)
 qed
 
 lemma parse_ipv6_address_compressed_identity:
       "parse_ipv6_address_compressed (ipv6addr_syntax_compressed_to_list (ipv6_syntax)) = Some ipv6_syntax"
   by(cases ipv6_syntax; simp add: parse_ipv6_address_compressed_def)
 
 
 lemma parse_ipv6_address_compressed_someE:
   assumes "parse_ipv6_address_compressed as = Some ipv6"
   obtains
     "as = [None]" "ipv6 = (IPv6AddrCompressed1_0 ())"  |
     a where "as = [None, Some a]" "ipv6 = (IPv6AddrCompressed1_1 () a)"  |
     a b where "as = [None, Some a, Some b]" "ipv6 = (IPv6AddrCompressed1_2 () a b)"  |
     a b c where "as = [None, Some a, Some b, Some c]" "ipv6 = (IPv6AddrCompressed1_3 () a b c)" |
     a b c d where "as = [None, Some a, Some b, Some c, Some d]" "ipv6 = (IPv6AddrCompressed1_4 () a b c d)" |
     a b c d e where "as = [None, Some a, Some b, Some c, Some d, Some e]" "ipv6 = (IPv6AddrCompressed1_5 () a b c d e)" |
     a b c d e f where "as = [None, Some a, Some b, Some c, Some d, Some e, Some f]" "ipv6 = (IPv6AddrCompressed1_6 () a b c d e f)" |
     a b c d e f g where "as = [None, Some a, Some b, Some c, Some d, Some e, Some f, Some g]" "ipv6 = (IPv6AddrCompressed1_7 () a b c d e f g)" |
   
     a where "as = [Some a, None]" "ipv6 = (IPv6AddrCompressed2_1 a ())" |
     a b where "as = [Some a, None, Some b]" "ipv6 = (IPv6AddrCompressed2_2 a () b)" |
     a b c where "as = [Some a, None, Some b, Some c]" "ipv6 = (IPv6AddrCompressed2_3 a () b c)" |
     a b c d where "as = [Some a, None, Some b, Some c, Some d]" "ipv6 = (IPv6AddrCompressed2_4 a () b c d)" |
     a b c d e where "as = [Some a, None, Some b, Some c, Some d, Some e]" "ipv6 = (IPv6AddrCompressed2_5 a () b c d e)" |
     a b c d e f where "as = [Some a, None, Some b, Some c, Some d, Some e, Some f]" "ipv6 = (IPv6AddrCompressed2_6 a () b c d e f)" |
     a b c d e f g where "as = [Some a, None, Some b, Some c, Some d, Some e, Some f, Some g]" "ipv6 = (IPv6AddrCompressed2_7 a () b c d e f g)" |
   
     a b where "as = [Some a, Some b, None]" "ipv6 = (IPv6AddrCompressed3_2 a b ())" |
     a b c where "as = [Some a, Some b, None, Some c]" "ipv6 = (IPv6AddrCompressed3_3 a b () c)" |
     a b c d where "as = [Some a, Some b, None, Some c, Some d]" "ipv6 = (IPv6AddrCompressed3_4 a b () c d)" |
     a b c d e where "as = [Some a, Some b, None, Some c, Some d, Some e]" "ipv6 = (IPv6AddrCompressed3_5 a b () c d e)" |
     a b c d e f where "as = [Some a, Some b, None, Some c, Some d, Some e, Some f]" "ipv6 = (IPv6AddrCompressed3_6 a b () c d e f)" |
     a b c d e f g where "as = [Some a, Some b, None, Some c, Some d, Some e, Some f, Some g]" "ipv6 = (IPv6AddrCompressed3_7 a b () c d e f g)" |
   
     a b c where "as = [Some a, Some b, Some c, None]" "ipv6 = (IPv6AddrCompressed4_3 a b c ())" |
     a b c d where "as = [Some a, Some b, Some c, None, Some d]" "ipv6 = (IPv6AddrCompressed4_4 a b c () d)" |
     a b c d e where "as = [Some a, Some b, Some c, None, Some d, Some e]" "ipv6 = (IPv6AddrCompressed4_5 a b c () d e)" |
     a b c d e f where "as = [Some a, Some b, Some c, None, Some d, Some e, Some f]" "ipv6 = (IPv6AddrCompressed4_6 a b c () d e f)" |
     a b c d e f g where "as = [Some a, Some b, Some c, None, Some d, Some e, Some f, Some g]" "ipv6 = (IPv6AddrCompressed4_7 a b c () d e f g)" |
   
     a b c d where "as = [Some a, Some b, Some c, Some d, None]" "ipv6 = (IPv6AddrCompressed5_4 a b c d ())" |
     a b c d e where "as = [Some a, Some b, Some c, Some d, None, Some e]" "ipv6 = (IPv6AddrCompressed5_5 a b c d () e)" |
     a b c d e f where "as = [Some a, Some b, Some c, Some d, None, Some e, Some f]" "ipv6 = (IPv6AddrCompressed5_6 a b c d () e f)" |
     a b c d e f g where "as = [Some a, Some b, Some c, Some d, None, Some e, Some f, Some g]" "ipv6 = (IPv6AddrCompressed5_7 a b c d () e f g)" |
   
     a b c d e where "as = [Some a, Some b, Some c, Some d, Some e, None]" "ipv6 = (IPv6AddrCompressed6_5 a b c d e ())" |
     a b c d e f where "as = [Some a, Some b, Some c, Some d, Some e, None, Some f]" "ipv6 = (IPv6AddrCompressed6_6 a b c d e () f)" |
     a b c d e f g where "as = [Some a, Some b, Some c, Some d, Some e, None, Some f, Some g]" "ipv6 = (IPv6AddrCompressed6_7 a b c d e () f g)" |
   
     a b c d e f where "as = [Some a, Some b, Some c, Some d, Some e, Some f, None]" "ipv6 = (IPv6AddrCompressed7_6 a b c d e f ())" |
     a b c d e f g where "as = [Some a, Some b, Some c, Some d, Some e, Some f, None, Some g]" "ipv6 = (IPv6AddrCompressed7_7 a b c d e f () g)" |
 
     a b c d e f g where "as = [Some a, Some b, Some c, Some d, Some e, Some f, Some g, None]" "ipv6 = (IPv6AddrCompressed8_7 a b c d e f g ())"
 using assms
 unfolding parse_ipv6_address_compressed_def
 by (auto split: list.split_asm option.split_asm) (* takes a minute *)
 
 lemma parse_ipv6_address_compressed_identity2:
       "ipv6addr_syntax_compressed_to_list ipv6_syntax = ls \<longleftrightarrow>
         (parse_ipv6_address_compressed ls) = Some ipv6_syntax"
       (is "?lhs = ?rhs")
 proof
   assume ?rhs
   thus ?lhs
     by (auto elim: parse_ipv6_address_compressed_someE)
 next
   assume ?lhs
   thus ?rhs
     by (cases ipv6_syntax) (auto simp: parse_ipv6_address_compressed_def)
 qed
 
 text\<open>Valid IPv6 compressed notation:
   \<^item> at most one omission
   \<^item> at most 7 pieces
 \<close>
 lemma RFC_4291_format: "parse_ipv6_address_compressed as \<noteq> None \<longleftrightarrow>
        length (filter (\<lambda>p. p = None) as) = 1 \<and> length (filter (\<lambda>p. p \<noteq> None) as) \<le> 7"
        (is "?lhs = ?rhs")
 proof
   assume ?lhs
   then obtain addr where "parse_ipv6_address_compressed as = Some addr"
     by blast
   thus ?rhs
     by (elim parse_ipv6_address_compressed_someE; simp)
 next
   assume ?rhs
   thus ?lhs
     unfolding parse_ipv6_address_compressed_def
     by (auto split: option.split list.split if_split_asm)
 qed
 
   text_raw\<open>
   \begin{verbatim}
   3. An alternative form that is sometimes more convenient when dealing
       with a mixed environment of IPv4 and IPv6 nodes is
       x:x:x:x:x:x:d.d.d.d, where the 'x's are the hexadecimal values of
       the six high-order 16-bit pieces of the address, and the 'd's are
       the decimal values of the four low-order 8-bit pieces of the
       address (standard IPv4 representation).  Examples:
 
          0:0:0:0:0:0:13.1.68.3
          0:0:0:0:0:FFFF:129.144.52.38
 
       or in compressed form:
 
          ::13.1.68.3
          ::FFFF:129.144.52.38
   \end{verbatim}
 
   This is currently not supported by our library!
 \<close>
   (*TODO*)
   (*TODO: oh boy, they can also be compressed*)
 
   subsection\<open>Semantics\<close>
 
   context
     includes bit_operations_syntax
   begin
 
   fun ipv6preferred_to_int :: "ipv6addr_syntax \<Rightarrow> ipv6addr" where
     "ipv6preferred_to_int (IPv6AddrPreferred a b c d e f g h) = (ucast a << (16 * 7)) OR
                                                                 (ucast b << (16 * 6)) OR
                                                                 (ucast c << (16 * 5)) OR
                                                                 (ucast d << (16 * 4)) OR
                                                                 (ucast e << (16 * 3)) OR
                                                                 (ucast f << (16 * 2)) OR
                                                                 (ucast g << (16 * 1)) OR
                                                                 (ucast h << (16 * 0))"
 
   lemma "ipv6preferred_to_int (IPv6AddrPreferred 0x2001 0xDB8 0x0 0x0 0x8 0x800 0x200C 0x417A) = 
           42540766411282592856906245548098208122" by eval
 
   lemma "ipv6preferred_to_int (IPv6AddrPreferred 0xFF01 0x0 0x0 0x0 0x0 0x0 0x0 0x101) = 
           338958331222012082418099330867817087233" by eval
 
   declare ipv6preferred_to_int.simps[simp del]
 
   definition int_to_ipv6preferred :: "ipv6addr \<Rightarrow> ipv6addr_syntax" where
     "int_to_ipv6preferred i = IPv6AddrPreferred (ucast ((i AND 0xFFFF0000000000000000000000000000) >> 16*7))
                                                 (ucast ((i AND 0xFFFF000000000000000000000000) >> 16*6))
                                                 (ucast ((i AND 0xFFFF00000000000000000000) >> 16*5))
                                                 (ucast ((i AND 0xFFFF0000000000000000) >> 16*4))
                                                 (ucast ((i AND 0xFFFF000000000000) >> 16*3))
                                                 (ucast ((i AND 0xFFFF00000000) >> 16*2))
                                                 (ucast ((i AND 0xFFFF0000) >> 16*1))
                                                 (ucast ((i AND 0xFFFF)))"
 
   lemma "int_to_ipv6preferred 42540766411282592856906245548098208122 =
          IPv6AddrPreferred 0x2001 0xDB8 0x0 0x0 0x8 0x800 0x200C 0x417A" by eval
 
   lemma word128_masks_ipv6pieces:
     "(0xFFFF0000000000000000000000000000::ipv6addr) = (mask 16) << 112"
     "(0xFFFF000000000000000000000000::ipv6addr) = (mask 16) << 96"
     "(0xFFFF00000000000000000000::ipv6addr) = (mask 16) << 80"
     "(0xFFFF0000000000000000::ipv6addr) = (mask 16) << 64"
     "(0xFFFF000000000000::ipv6addr) = (mask 16) << 48"
     "(0xFFFF00000000::ipv6addr) = (mask 16) << 32"
     "(0xFFFF0000::ipv6addr) = (mask 16) << 16"
     "(0xFFFF::ipv6addr) = (mask 16)"
-    by (simp_all add: mask_eq push_bit_of_1)
+    by (simp_all add: mask_eq)
 
 
   text\<open>Correctness: round trip property one\<close>
+
   lemma ipv6preferred_to_int_int_to_ipv6preferred:
     "ipv6preferred_to_int (int_to_ipv6preferred ip) = ip"
   proof -
     have and_mask_shift_helper: "w AND (mask m << n) >> n << n = w AND (mask m << n)"
       for m n::nat and w::ipv6addr
       by (metis is_aligned_shift is_aligned_shiftr_shiftl shiftr_and_eq_shiftl)
     have ucast_ipv6_piece_rule:
       "length (dropWhile Not (to_bl w)) \<le> 16 \<Longrightarrow> (ucast::16 word \<Rightarrow> 128 word) ((ucast::128 word \<Rightarrow> 16 word) w) = w"
       for w::ipv6addr 
       by(rule ucast_short_ucast_long_ingoreLeadingZero) (simp_all)
     have ucast_ipv6_piece: "16 \<le> 128 - n \<Longrightarrow> 
       (ucast::16 word \<Rightarrow> 128 word) ((ucast::128 word \<Rightarrow> 16 word) (w AND (mask 16 << n) >> n)) << n = w AND (mask 16 << n)"
       for w::ipv6addr and n::nat
       apply(subst ucast_ipv6_piece_rule)
        apply(rule length_drop_mask_inner)
        apply(simp; fail)
       apply(subst and_mask_shift_helper)
       apply simp
       done
 
     have ucast16_ucast128_masks_highest_bits:
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF0000000000000000000000000000 >> 112)) << 112) = 
              (ip AND 0xFFFF0000000000000000000000000000)"
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF000000000000000000000000 >> 96)) << 96) =
            ip AND 0xFFFF000000000000000000000000"
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF00000000000000000000 >> 80)) << 80) =
            ip AND 0xFFFF00000000000000000000" 
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF0000000000000000 >> 64)) << 64) =
            ip AND 0xFFFF0000000000000000"
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF000000000000 >> 48)) << 48) =
            ip AND 0xFFFF000000000000"
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF00000000 >> 32)) << 32) =
            ip AND 0xFFFF00000000"
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF0000 >> 16)) << 16) =
            ip AND 0xFFFF0000"
-            apply (simp_all add: word128_masks_ipv6pieces ucast_ipv6_piece and_mask2 word_size flip: take_bit_eq_mask)
-            apply (simp_all add: bit_eq_iff)
-            apply (auto simp add: bit_simps)
+            apply (simp_all only: word128_masks_ipv6pieces ucast_ipv6_piece and_mask2 word_size bit_eq_iff bit_simps comp_def)
+      apply auto
       done
 
     have ucast16_ucast128_masks_highest_bits0: 
       "(ucast ((ucast::ipv6addr \<Rightarrow> 16 word) (ip AND 0xFFFF))) = ip AND 0xFFFF"
-      apply(subst word128_masks_ipv6pieces)+
-      apply(subst ucast_short_ucast_long_ingoreLeadingZero)
-        apply simp_all
-      by (simp add: length_drop_mask)
+      apply (simp only: word128_masks_ipv6pieces flip: take_bit_eq_mask)
+      apply (simp add: unsigned_ucast_eq)
+      done
 
     have mask_len_word:"n = (LENGTH('a)) \<Longrightarrow> w AND mask n = w"
       for n and w::"'a::len word" by (simp add: mask_eq_iff) 
 
     have ipv6addr_16word_pieces_compose_or:
             "ip && (mask 16 << 112) ||
              ip && (mask 16 << 96) ||
              ip && (mask 16 << 80) ||
              ip && (mask 16 << 64) ||
              ip && (mask 16 << 48) ||
              ip && (mask 16 << 32) ||
              ip && (mask 16 << 16) ||
              ip && mask 16 =
              ip"
       apply(subst word_ao_dist2[symmetric])+
-      apply(simp add: mask_eq push_bit_of_1)
+      apply(simp add: mask_numeral)
       apply(subst mask128)
       apply(rule mask_len_word)
       apply simp
       done
 
     show ?thesis
-      apply (simp add: ipv6preferred_to_int.simps int_to_ipv6preferred_def)
-      apply (simp add: ucast16_ucast128_masks_highest_bits ucast16_ucast128_masks_highest_bits0)
-      apply (simp add: word128_masks_ipv6pieces ucast_ucast_mask)
+      apply (simp add: ipv6preferred_to_int.simps int_to_ipv6preferred_def shiftl_def shiftr_def)
+      apply (simp only: word128_masks_ipv6pieces flip: take_bit_eq_mask)
+      apply (simp add: unsigned_ucast_eq push_bit_take_bit)
       using ipv6addr_16word_pieces_compose_or
-      apply (simp flip: push_bit_and add: shiftr_and_eq_shiftl)
+      apply (simp add: take_bit_push_bit slice_eq_mask)
+      apply (simp add: take_bit_eq_mask shiftl_def push_bit_mask_eq)
       done
   qed
 
   text\<open>Correctness: round trip property two\<close>
   lemma int_to_ipv6preferred_ipv6preferred_to_int: "int_to_ipv6preferred (ipv6preferred_to_int ip) = ip"
   proof -
     note ucast_shift_simps=helper_masked_ucast_generic helper_masked_ucast_reverse_generic
                            helper_masked_ucast_generic[where n=0, simplified]
                            helper_masked_ucast_equal_generic 
     note ucast_simps=helper_masked_ucast_reverse_generic[where m=0, simplified]
                      helper_masked_ucast_equal_generic[where n=0, simplified]
     show ?thesis
     apply (cases ip, rename_tac a b c d e f g h)
     apply (simp add: ipv6preferred_to_int.simps int_to_ipv6preferred_def)
     apply (simp add: word128_masks_ipv6pieces)
       apply (simp add: word_ao_dist ucast_shift_simps ucast_simps)
-      apply (simp add: unsigned_or_eq)
-      apply (simp flip: take_bit_eq_mask add: unsigned_take_bit_eq take_bit_word_eq_self)
-      apply (simp add: shiftl_shiftr1 shiftl_shiftr2)
-      apply (simp flip: take_bit_eq_mask push_bit_and add: word_size)
-      apply (simp add: unsigned_take_bit_eq take_bit_word_eq_self)
-      apply (simp flip: unsigned_take_bit_eq)
-      apply (simp add: unsigned_ucast_eq)
-      apply (simp add: unsigned_push_bit_eq take_bit_word_eq_self)
-      apply (simp flip: ucast_drop_bit_eq)
       done
   qed
 
 
 text\<open>compressed to preferred format\<close>
 fun ipv6addr_c2p :: "ipv6addr_syntax_compressed \<Rightarrow> ipv6addr_syntax" where
     "ipv6addr_c2p (IPv6AddrCompressed1_0 ()) = IPv6AddrPreferred 0 0 0 0 0 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed1_1 () h) = IPv6AddrPreferred 0 0 0 0 0 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_2 () g h) = IPv6AddrPreferred 0 0 0 0 0 0 g h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_3 () f g h) = IPv6AddrPreferred 0 0 0 0 0 f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_4 () e f g h) = IPv6AddrPreferred 0 0 0 0 e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_5 () d e f g h) = IPv6AddrPreferred 0 0 0 d e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_6 () c d e f g h) = IPv6AddrPreferred 0 0 c d e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed1_7 () b c d e f g h) = IPv6AddrPreferred 0 b c d e f g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed2_1 a ()) = IPv6AddrPreferred a 0 0 0 0 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed2_2 a () h) = IPv6AddrPreferred a 0 0 0 0 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed2_3 a () g h) = IPv6AddrPreferred a 0 0 0 0 0 g h"
   | "ipv6addr_c2p (IPv6AddrCompressed2_4 a () f g h) = IPv6AddrPreferred a 0 0 0 0 f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed2_5 a () e f g h) = IPv6AddrPreferred a 0 0 0 e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed2_6 a () d e f g h) = IPv6AddrPreferred a 0 0 d e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed2_7 a () c d e f g h) = IPv6AddrPreferred a 0 c d e f g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed3_2 a b ()) = IPv6AddrPreferred a b 0 0 0 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed3_3 a b () h) = IPv6AddrPreferred a b 0 0 0 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed3_4 a b () g h) = IPv6AddrPreferred a b 0 0 0 0 g h"
   | "ipv6addr_c2p (IPv6AddrCompressed3_5 a b () f g h) = IPv6AddrPreferred a b 0 0 0 f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed3_6 a b () e f g h) = IPv6AddrPreferred a b 0 0 e f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed3_7 a b () d e f g h) = IPv6AddrPreferred a b 0 d e f g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed4_3 a b c ()) = IPv6AddrPreferred a b c 0 0 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed4_4 a b c () h) = IPv6AddrPreferred a b c 0 0 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed4_5 a b c () g h) = IPv6AddrPreferred a b c 0 0 0 g h"
   | "ipv6addr_c2p (IPv6AddrCompressed4_6 a b c () f g h) = IPv6AddrPreferred a b c 0 0 f g h"
   | "ipv6addr_c2p (IPv6AddrCompressed4_7 a b c () e f g h) = IPv6AddrPreferred a b c 0 e f g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed5_4 a b c d ()) = IPv6AddrPreferred a b c d 0 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed5_5 a b c d () h) = IPv6AddrPreferred a b c d 0 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed5_6 a b c d () g h) = IPv6AddrPreferred a b c d 0 0 g h"
   | "ipv6addr_c2p (IPv6AddrCompressed5_7 a b c d () f g h) = IPv6AddrPreferred a b c d 0 f g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed6_5 a b c d e ()) = IPv6AddrPreferred a b c d e 0 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed6_6 a b c d e () h) = IPv6AddrPreferred a b c d e 0 0 h"
   | "ipv6addr_c2p (IPv6AddrCompressed6_7 a b c d e () g h) = IPv6AddrPreferred a b c d e 0 g h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed7_6 a b c d e f ()) = IPv6AddrPreferred a b c d e f 0 0"
   | "ipv6addr_c2p (IPv6AddrCompressed7_7 a b c d e f () h) = IPv6AddrPreferred a b c d e f 0 h"
 
   | "ipv6addr_c2p (IPv6AddrCompressed8_7 a b c d e f g ()) = IPv6AddrPreferred a b c d e f g 0"
 
 
 definition ipv6_unparsed_compressed_to_preferred :: "((16 word) option) list \<Rightarrow> ipv6addr_syntax option" where
   "ipv6_unparsed_compressed_to_preferred ls = (
     if
       length (filter (\<lambda>p. p = None) ls) \<noteq> 1 \<or> length (filter (\<lambda>p. p \<noteq> None) ls) > 7
     then
       None
     else
       let
         before_omission = map the (takeWhile (\<lambda>x. x \<noteq> None) ls);
         after_omission = map the (drop 1 (dropWhile (\<lambda>x. x \<noteq> None) ls));
         num_omissions = 8 - (length before_omission + length after_omission);
         expanded = before_omission @ (replicate num_omissions 0) @ after_omission
       in
         case expanded of [a,b,c,d,e,f,g,h] \<Rightarrow> Some (IPv6AddrPreferred a b c d e f g h)
                          | _               \<Rightarrow> None
       )"
 
   lemma "ipv6_unparsed_compressed_to_preferred
     [Some 0x2001, Some 0xDB8, None, Some 0x8, Some 0x800, Some 0x200C, Some 0x417A]
       = Some (IPv6AddrPreferred 0x2001 0xDB8 0 0 8 0x800 0x200C 0x417A)" by eval
 
   lemma "ipv6_unparsed_compressed_to_preferred [None] = Some (IPv6AddrPreferred 0 0 0 0 0 0 0 0)" by eval
 
   lemma "ipv6_unparsed_compressed_to_preferred [] = None" by eval
 
 
   lemma ipv6_unparsed_compressed_to_preferred_identity1:
    "ipv6_unparsed_compressed_to_preferred (ipv6addr_syntax_compressed_to_list ipv6compressed) = Some ipv6prferred
     \<longleftrightarrow> ipv6addr_c2p ipv6compressed = ipv6prferred"
     by (cases ipv6compressed) (simp_all add: ipv6_unparsed_compressed_to_preferred_def numeral_eq_Suc) (*1s*)
  
   lemma ipv6_unparsed_compressed_to_preferred_identity2: 
     "ipv6_unparsed_compressed_to_preferred ls = Some ipv6prferred
      \<longleftrightarrow> (\<exists>ipv6compressed. parse_ipv6_address_compressed ls = Some ipv6compressed \<and>
                            ipv6addr_c2p ipv6compressed = ipv6prferred)"
   apply(rule iffI)
    apply(subgoal_tac "parse_ipv6_address_compressed ls \<noteq> None")
     prefer 2
     apply(subst RFC_4291_format)
     apply(simp add: ipv6_unparsed_compressed_to_preferred_def split: if_split_asm; fail)
    apply(simp)
    apply(erule exE, rename_tac ipv6compressed)
    apply(rule_tac x="ipv6compressed" in exI)
    apply(simp)
    apply(subgoal_tac "(ipv6addr_syntax_compressed_to_list ipv6compressed = ls)")
     prefer 2
     using parse_ipv6_address_compressed_identity2 apply presburger
    using ipv6_unparsed_compressed_to_preferred_identity1 apply blast
   apply(erule exE, rename_tac ipv6compressed)
   apply(subgoal_tac "(ipv6addr_syntax_compressed_to_list ipv6compressed = ls)")
    prefer 2
    using parse_ipv6_address_compressed_identity2 apply presburger
   using ipv6_unparsed_compressed_to_preferred_identity1 apply blast
   done
 
   end
 
 subsection\<open>IPv6 Pretty Printing (converting to compressed format)\<close>
 text_raw\<open>
 RFC5952:
 \begin{verbatim}
 4.  A Recommendation for IPv6 Text Representation
 
    A recommendation for a canonical text representation format of IPv6
    addresses is presented in this section.  The recommendation in this
    document is one that complies fully with [RFC4291], is implemented by
    various operating systems, and is human friendly.  The recommendation
    in this section SHOULD be followed by systems when generating an
    address to be represented as text, but all implementations MUST
    accept and be able to handle any legitimate [RFC4291] format.  It is
    advised that humans also follow these recommendations when spelling
    an address.
 
 4.1.  Handling Leading Zeros in a 16-Bit Field
 
    Leading zeros MUST be suppressed.  For example, 2001:0db8::0001 is
    not acceptable and must be represented as 2001:db8::1.  A single 16-
    bit 0000 field MUST be represented as 0.
 
 4.2.  "::" Usage
 
 4.2.1.  Shorten as Much as Possible
 
    The use of the symbol "::" MUST be used to its maximum capability.
    For example, 2001:db8:0:0:0:0:2:1 must be shortened to 2001:db8::2:1.
    Likewise, 2001:db8::0:1 is not acceptable, because the symbol "::"
    could have been used to produce a shorter representation 2001:db8::1.
 
 4.2.2.  Handling One 16-Bit 0 Field
 
    The symbol "::" MUST NOT be used to shorten just one 16-bit 0 field.
    For example, the representation 2001:db8:0:1:1:1:1:1 is correct, but
    2001:db8::1:1:1:1:1 is not correct.
 
 4.2.3.  Choice in Placement of "::"
 
    When there is an alternative choice in the placement of a "::", the
    longest run of consecutive 16-bit 0 fields MUST be shortened (i.e.,
    the sequence with three consecutive zero fields is shortened in 2001:
    0:0:1:0:0:0:1).  When the length of the consecutive 16-bit 0 fields
    are equal (i.e., 2001:db8:0:0:1:0:0:1), the first sequence of zero
    bits MUST be shortened.  For example, 2001:db8::1:0:0:1 is correct
    representation.
 
 4.3.  Lowercase
 
    The characters "a", "b", "c", "d", "e", and "f" in an IPv6 address
    MUST be represented in lowercase.
 \end{verbatim}
 \<close>
 text\<open>See @{file \<open>IP_Address_toString.thy\<close>} for examples and test cases.\<close>
 context
 begin
   private function goup_by_zeros :: "16 word list \<Rightarrow> 16 word list list" where
     "goup_by_zeros [] = []" |
     "goup_by_zeros (x#xs) = (
         if x = 0
         then takeWhile (\<lambda>x. x = 0) (x#xs) # (goup_by_zeros (dropWhile (\<lambda>x. x = 0) xs))
         else [x]#(goup_by_zeros xs))"
   by(pat_completeness, auto)
   
   termination goup_by_zeros
 	 apply(relation "measure (\<lambda>xs. length xs)")
 	   apply(simp_all)
 	 by (simp add: le_imp_less_Suc length_dropWhile_le)
 	
 	private lemma "goup_by_zeros [0,1,2,3,0,0,0,0,3,4,0,0,0,2,0,0,2,0,3,0] =
 	        [[0], [1], [2], [3], [0, 0, 0, 0], [3], [4], [0, 0, 0], [2], [0, 0], [2], [0], [3], [0]]"
 	by eval
 	
 	private lemma "concat (goup_by_zeros ls) = ls"
 	  by(induction ls rule:goup_by_zeros.induct) simp+
 	
 	private lemma "[] \<notin> set (goup_by_zeros ls)"
 	  by(induction ls rule:goup_by_zeros.induct) simp+
 	  
   private primrec List_replace1 :: "'a \<Rightarrow> 'a \<Rightarrow> 'a list \<Rightarrow> 'a list" where
     "List_replace1 _ _ [] = []" |
     "List_replace1 a b (x#xs) = (if a = x then b#xs else x#List_replace1 a b xs)"
     
 	private lemma "List_replace1 a a ls = ls"
 	  by(induction ls) simp_all
 	
 	private lemma "a \<notin> set ls \<Longrightarrow> List_replace1 a b ls = ls"
 	  by(induction ls) simp_all
 	
 	private lemma "a \<in> set ls \<Longrightarrow> b \<in> set (List_replace1 a b ls)"
 	  apply(induction ls)
 	   apply(simp)
 	  apply(simp)
 	  by blast
   
 	private fun List_explode :: "'a list list \<Rightarrow> ('a option) list" where
 	  "List_explode [] = []" |
 	  "List_explode ([]#xs) = None#List_explode xs" |
 	  "List_explode (xs1#xs2) = map Some xs1@List_explode xs2"
 	  
   private lemma "List_explode [[0::int], [2,3], [], [3,4]] = [Some 0, Some 2, Some 3, None, Some 3, Some 4]"
   by eval
 
   private lemma List_explode_def: 
     "List_explode xss = concat (map (\<lambda>xs. if xs = [] then [None] else map Some xs) xss)"
     by(induction xss rule: List_explode.induct) simp+
 	  
   private lemma List_explode_no_empty: "[] \<notin> set xss \<Longrightarrow> List_explode xss = map Some (concat xss)"
     by(induction xss rule: List_explode.induct) simp+
 
   private lemma List_explode_replace1: "[] \<notin> set xss \<Longrightarrow> foo \<in> set xss \<Longrightarrow>
           List_explode (List_replace1 foo [] xss) =
             map Some (concat (takeWhile (\<lambda>xs. xs \<noteq> foo) xss)) @ [None] @
               map Some (concat (tl (dropWhile (\<lambda>xs. xs \<noteq> foo) xss)))"
     apply(induction xss rule: List_explode.induct)
       apply(simp; fail)
      apply(simp; fail)
     apply(simp)
     apply safe
       apply(simp_all add: List_explode_no_empty)
     done
     
   fun ipv6_preferred_to_compressed :: "ipv6addr_syntax \<Rightarrow> ((16 word) option) list" where
   "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (
     let lss = goup_by_zeros [a,b,c,d,e,f,g,h];
         max_zero_seq = foldr (\<lambda>xs. max (length xs)) lss 0;
         shortened = if max_zero_seq > 1 then List_replace1 (replicate max_zero_seq 0) [] lss else lss
     in
       List_explode shortened
     )"
   declare ipv6_preferred_to_compressed.simps[simp del]
 
   private lemma foldr_max_length: "foldr (\<lambda>xs. max (length xs)) lss n = fold max (map length lss) n"
     apply(subst List.foldr_fold)
      apply fastforce
     apply(induction lss arbitrary: n)
      apply(simp; fail)
     apply(simp)
     done
 
   private lemma List_explode_goup_by_zeros: "List_explode (goup_by_zeros xs) = map Some xs"
     apply(induction xs rule: goup_by_zeros.induct)
      apply(simp; fail)
     apply(simp)
     apply(safe)
      apply(simp)
     by (metis map_append takeWhile_dropWhile_id)
   
   private definition "max_zero_streak xs \<equiv> foldr (\<lambda>xs. max (length xs)) (goup_by_zeros xs) 0"    
 
   private lemma max_zero_streak_def2: "max_zero_streak xs = fold max (map length (goup_by_zeros xs)) 0"
     unfolding max_zero_streak_def
     by(simp add: foldr_max_length)
 
   private lemma ipv6_preferred_to_compressed_pull_out_if:
     "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (
     if max_zero_streak [a,b,c,d,e,f,g,h] > 1 then
       List_explode (List_replace1 (replicate (max_zero_streak [a,b,c,d,e,f,g,h]) 0) [] (goup_by_zeros [a,b,c,d,e,f,g,h]))
     else
       map Some [a,b,c,d,e,f,g,h]
     )"
     apply (simp only: ipv6_preferred_to_compressed.simps Let_def max_zero_streak_def List_explode_goup_by_zeros)
     using List_explode_goup_by_zeros by presburger
 
 
     
   private lemma "ipv6_preferred_to_compressed (IPv6AddrPreferred 0 0 0 0 0 0 0 0) = [None]" by eval
   private lemma "ipv6_preferred_to_compressed (IPv6AddrPreferred 0x2001 0xDB8 0 0 8 0x800 0x200C 0x417A) =
                 [Some 0x2001, Some 0xDB8, None,           Some 8, Some 0x800, Some 0x200C, Some 0x417A]" by eval
   private lemma "ipv6_preferred_to_compressed (IPv6AddrPreferred 0x2001 0xDB8 0 3 8 0x800 0x200C 0x417A) =
                 [Some 0x2001, Some 0xDB8, Some 0, Some 3, Some 8, Some 0x800, Some 0x200C, Some 0x417A]" by eval
 
   (*the output should even conform to RFC5952, ...*)
   lemma ipv6_preferred_to_compressed_RFC_4291_format:
     "ipv6_preferred_to_compressed ip = as \<Longrightarrow> 
           length (filter (\<lambda>p. p = None) as) = 0 \<and> length as = 8
           \<or>
           length (filter (\<lambda>p. p = None) as) = 1 \<and> length (filter (\<lambda>p. p \<noteq> None) as) \<le> 7"
   apply(cases ip)
   apply(simp add: ipv6_preferred_to_compressed_pull_out_if)
   apply(simp only: split: if_split_asm)
    subgoal for a b c d e f g h
    apply(rule disjI2)
    apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
          case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
    by(auto simp add: max_zero_streak_def) (*1min*)
   subgoal
   apply(rule disjI1)
   apply(simp)
   by force
   done
 
   \<comment> \<open>Idea for the following proof:\<close>
   private lemma "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = None#xs \<Longrightarrow>
       xs = map Some (dropWhile (\<lambda>x. x=0) [a,b,c,d,e,f,g,h])"
     apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
           case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
     by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*20s*)
 
 
  
   lemma ipv6_preferred_to_compressed:
     assumes "ipv6_unparsed_compressed_to_preferred (ipv6_preferred_to_compressed ip) = Some ip'"
     shows "ip = ip'"
   proof -
     from assms have 1: "\<exists>ipv6compressed.
          parse_ipv6_address_compressed (ipv6_preferred_to_compressed ip) = Some ipv6compressed \<and>
          ipv6addr_c2p ipv6compressed = ip'" using ipv6_unparsed_compressed_to_preferred_identity2 by simp
   
     obtain a b c d e f g h where ip: "ip = IPv6AddrPreferred a b c d e f g h" by(cases ip)
   
     have ipv6_preferred_to_compressed_None1:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [a,b,c,d,e,f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a b c d e f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None2:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [b,c,d,e,f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b c d e f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None3:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [c,d,e,f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c d e f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a' b'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None4:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#(Some c')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [d,e,f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c' d e f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a' b' c'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None5:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#(Some c')#(Some d')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [e,f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c' d' e f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a' b' c' d'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None6:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#(Some c')#(Some d')#(Some e')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [f,g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c' d' e' f g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a' b' c' d' e'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None7:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#(Some c')#(Some d')#(Some e')#(Some f')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [g,h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c' d' e' f' g h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'"  for xs a' b' c' d' e' f'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
     have ipv6_preferred_to_compressed_None8:
       "ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h) = (Some a')#(Some b')#(Some c')#(Some d')#(Some e')#(Some f')#(Some g')#None#xs \<Longrightarrow>
         (map Some (dropWhile (\<lambda>x. x=0) [h]) = xs \<Longrightarrow> (IPv6AddrPreferred a' b' c' d' e' f' g' h) = ip') \<Longrightarrow>
         (IPv6AddrPreferred a b c d e f g h) = ip'" for xs a' b' c' d' e' f' g'
       apply(case_tac "a=0",case_tac [!] "b=0",case_tac [!] "c=0",case_tac [!] "d=0",
             case_tac [!] "e=0",case_tac [!] "f=0",case_tac [!] "g=0",case_tac [!] "h=0")
       by(simp_all add: ipv6_preferred_to_compressed_pull_out_if max_zero_streak_def) (*5s*)
 
     have 2: "parse_ipv6_address_compressed (ipv6_preferred_to_compressed (IPv6AddrPreferred a b c d e f g h))
                 = Some ipv6compressed \<Longrightarrow>
        ipv6addr_c2p ipv6compressed = ip' \<Longrightarrow>
        IPv6AddrPreferred a b c d e f g h = ip'"
     for ipv6compressed
       apply(erule parse_ipv6_address_compressed_someE)
                                          apply(simp_all)
                                          apply(erule ipv6_preferred_to_compressed_None1, simp split: if_split_asm)+
                                  apply(erule ipv6_preferred_to_compressed_None2, simp split: if_split_asm)+
                          apply(erule ipv6_preferred_to_compressed_None3, simp split: if_split_asm)+
                     apply(erule ipv6_preferred_to_compressed_None4, simp split: if_split_asm)+
                apply(erule ipv6_preferred_to_compressed_None5, simp split: if_split_asm)+
            apply(erule ipv6_preferred_to_compressed_None6, simp split: if_split_asm)+
         apply(erule ipv6_preferred_to_compressed_None7, simp split: if_split_asm)+
       apply(erule ipv6_preferred_to_compressed_None8, simp split: if_split_asm)
       done
     from 1 2 ip show ?thesis by(elim exE conjE, simp)
   qed
 
 end
 
 end
diff --git a/thys/IP_Addresses/Lib_Word_toString.thy b/thys/IP_Addresses/Lib_Word_toString.thy
--- a/thys/IP_Addresses/Lib_Word_toString.thy
+++ b/thys/IP_Addresses/Lib_Word_toString.thy
@@ -1,220 +1,218 @@
 theory Lib_Word_toString
 imports Lib_Numbers_toString
         Word_Lib.Word_Lemmas
 begin
 
 context unique_euclidean_semiring_numeral
 begin
 
 lemma exp_estimate [simp]:
   \<open>numeral Num.One \<le> 2 ^ n\<close>  (is \<open>?P1\<close>)
   \<open>numeral Num.One < 2 ^ n \<longleftrightarrow> 1 \<le> n\<close>  (is \<open>?P2\<close>)
   \<open>numeral (Num.Bit0 k) \<le> 2 ^ n \<longleftrightarrow> 1 \<le> n \<and> numeral k \<le> 2 ^ (n - 1)\<close>  (is \<open>?P3\<close>)
   \<open>numeral (Num.Bit0 k) < 2 ^ n \<longleftrightarrow> 1 \<le> n \<and> numeral k < 2 ^ (n - 1)\<close>  (is \<open>?P4\<close>)
   \<open>numeral (Num.Bit1 k) \<le> 2 ^ n \<longleftrightarrow> 1 \<le> n \<and> numeral k < 2 ^ (n - 1)\<close>  (is \<open>?P5\<close>)
   \<open>numeral (Num.Bit1 k) < 2 ^ n \<longleftrightarrow> 1 \<le> n \<and> numeral k < 2 ^ (n - 1)\<close>  (is \<open>?P6\<close>)
 proof -
   show ?P1
     by simp
   show ?P2
     using one_less_power power_eq_if by auto
 
   let ?K = \<open>numeral k :: nat\<close>
 
   define m where \<open>m = n - 1\<close>
   then consider \<open>n = 0\<close> | \<open>n = Suc m\<close>
     by (cases n) simp_all
   note Suc = this
 
   have \<open>2 * ?K \<le> 2 * 2 ^ m \<longleftrightarrow> ?K \<le> 2 ^ m\<close>
     by linarith
   then have \<open>of_nat (2 * ?K) \<le> of_nat (2 * 2 ^ m) \<longleftrightarrow> of_nat ?K \<le> of_nat (2 ^ m)\<close>
     by (simp only: of_nat_le_iff)
   then show ?P3
     by (auto intro: Suc)
 
   have \<open>2 * ?K < 2 * 2 ^ m \<longleftrightarrow> ?K < 2 ^ m\<close>
     by linarith
   then have \<open>of_nat (2 * ?K) < of_nat (2 * 2 ^ m) \<longleftrightarrow> of_nat ?K < of_nat (2 ^ m)\<close>
     by (simp only: of_nat_less_iff)
   then show ?P4
     by (auto intro: Suc)
 
   have \<open>Suc (2 * ?K) \<le> 2 * 2 ^ m \<longleftrightarrow> ?K < 2 ^ m\<close>
     by linarith
   then have \<open>of_nat (Suc (2 * ?K)) \<le> of_nat (2 * 2 ^ m) \<longleftrightarrow> of_nat ?K < of_nat (2 ^ m)\<close>
     by (simp only: of_nat_le_iff of_nat_less_iff)
   then show ?P5
     by (auto intro: Suc)
 
   have \<open>Suc (2 * ?K) < 2 * 2 ^ m \<longleftrightarrow> ?K < 2 ^ m\<close>
     by linarith
   then have \<open>of_nat (Suc (2 * ?K)) < of_nat (2 * 2 ^ m) \<longleftrightarrow> of_nat ?K < of_nat (2 ^ m)\<close>
     by (simp only: of_nat_less_iff)
   then show ?P6
     by (auto intro: Suc)
 
 qed
 
 end
 
 
 section\<open>Printing Machine Words\<close>
 
 (*imitation of http://stackoverflow.com/questions/23864965/string-of-nat-in-isabelle*)
 (*parameters:
     lc = lower-case
     w  = word to print*)
 definition string_of_word_single :: "bool \<Rightarrow> 'a::len word \<Rightarrow> string" where
   "string_of_word_single lc w \<equiv>
     (if
        w < 10
      then
        [char_of (48 + unat w)]
      else if
        w < 36
      then
        [char_of ((if lc then 87 else 55) + unat w)]
      else
        undefined)"
 
 text\<open>Example:\<close>
 lemma "let word_upto = ((\<lambda> i j. map (of_nat \<circ> nat) [i .. j]) :: int \<Rightarrow> int \<Rightarrow> 32 word list)
        in map (string_of_word_single False) (word_upto 1 35) =
   [''1'', ''2'', ''3'', ''4'', ''5'', ''6'', ''7'', ''8'', ''9'',
    ''A'', ''B'', ''C'', ''D'', ''E'', ''F'', ''G'', ''H'', ''I'',
    ''J'', ''K'', ''L'', ''M'', ''N'', ''O'', ''P'', ''Q'', ''R'',
    ''S'', ''T'', ''U'', ''V'', ''W'', ''X'', ''Y'', ''Z'']" by eval
 
 (* parameters: lowercase, base, minimum length - 1, to-be-serialized word *) 
 function string_of_word :: "bool \<Rightarrow> ('a :: len) word \<Rightarrow> nat \<Rightarrow> ('a :: len) word \<Rightarrow> string" where
   "string_of_word lc base ml w =
     (if
        base < 2 \<or> LENGTH('a) < 2
      then
        undefined
      else if
        w < base \<and> ml = 0
      then
        string_of_word_single lc w
      else
        string_of_word lc base (ml - 1) (w div base) @ string_of_word_single lc (w mod base)
      )"
 by pat_completeness auto
 
 definition "hex_string_of_word l \<equiv> string_of_word True (16 :: ('a::len) word) l"
 definition "hex_string_of_word0 \<equiv> hex_string_of_word 0"
 (* be careful though, these functions only make sense with words > length 4.
    With 4 bits, base 16 is not representable. *)
 definition "dec_string_of_word0 \<equiv> string_of_word True 10 0"
 
 termination string_of_word
 	apply(relation "measure (\<lambda>(a,b,c,d). unat d + c)")
 	 apply(rule wf_measure)
 	apply(subst in_measure)
 	apply(clarsimp)
 	subgoal for base ml n
     apply(case_tac "ml \<noteq> 0")
      apply(simp add: less_eq_Suc_le unat_div)
     apply(simp)
     apply(subgoal_tac "(n div base) < n")
      apply(blast intro: unat_mono)
     apply(rule div_less_dividend_word)
      apply (auto simp add: not_less word_le_nat_alt)
   done
 done
 
 declare string_of_word.simps[simp del]
 
 lemma "hex_string_of_word0 (0xdeadbeef42 :: 42 word) = ''deadbeef42''" by eval
 
 lemma "hex_string_of_word 1 (0x1 :: 5 word) = ''01''" by eval
 lemma "hex_string_of_word 8 (0xff::32 word) = ''0000000ff''" by eval
 
 lemma "dec_string_of_word0 (8::32 word) = ''8''" by eval
 lemma "dec_string_of_word0 (3::2 word) = ''11''" by eval
 lemma "dec_string_of_word0 (-1::8 word) = ''255''" by eval
 
 lemma string_of_word_single_atoi:
   "n < 10 \<Longrightarrow> string_of_word_single True n = [char_of (48 + unat n)]"
   by(simp add: string_of_word_single_def)
 
 (*TODO: move!*)
 lemma bintrunc_pos_eq: "x \<ge> 0 \<Longrightarrow> take_bit n x = x \<longleftrightarrow> x < 2^n" for x :: int
   by (simp add: take_bit_int_eq_self_iff)
 
 (*The following lemma [symmetric] as [code_unfold] may give some cool speedup*)
 lemma string_of_word_base_ten_zeropad:
   fixes w ::"'a::len word"
   assumes lena: "LENGTH('a) \<ge> 5" (*word must be long enough to encode 10 = 0xA*)
   shows "base = 10 \<Longrightarrow> zero = 0 \<Longrightarrow> string_of_word True base zero w = string_of_nat (unat w)"
 proof(induction True base zero w rule: string_of_word.induct)
   case (1 base ml n)
 
   note  Word.word_less_no[simp del]
   note  Word.uint_bintrunc[simp del]
 
   define l where \<open>l = LENGTH('a) - 5\<close>
   with lena have l: \<open>LENGTH('a) = l + 5\<close>
     by simp
 
   have [simp]: \<open>take_bit LENGTH('a) (10 :: nat) = 10\<close>
     using lena by (auto simp add: take_bit_nat_eq_self_iff l Suc_lessI)
 
   have [simp]: \<open>take_bit LENGTH('a) (10 :: int) = 10\<close>
     using lena by (auto simp add: take_bit_int_eq_self_iff l)
       (smt (verit) zero_less_power)
 
   have unat_mod_ten: "unat (n mod 0xA) = unat n mod 10"
     by (simp add: nat_take_bit_eq unat_mod)
     
   have unat_div_ten: "(unat (n div 0xA)) = unat n div 10"
     by (simp add: nat_take_bit_eq unat_div)
 
   have n_less_ten_unat: "n < 0xA \<Longrightarrow> (unat n < 10)"
     by (simp add: unat_less_helper)
 
   have "0xA \<le> n \<Longrightarrow> 10 \<le> unat n" 
     by (simp add: nat_take_bit_eq word_le_nat_alt)
 
   hence n_less_ten_unat_not: "\<not> n < 0xA \<Longrightarrow> \<not> unat n < 10" by fastforce
   have not_wordlength_too_small: "\<not> LENGTH('a) < 2" using lena by fastforce
   have "2 \<le> (0xA::'a word)"
     by simp
   hence ten_not_less_two: "\<not> (0xA::'a word) < 2" by (simp add: Word.word_less_no Word.uint_bintrunc)
   with 1(2,3) have " \<not> (base < 2 \<or> LENGTH(32) < 2)"
     by(simp)
   with 1 not_wordlength_too_small have IH: "\<not> n < 0xA \<Longrightarrow> string_of_word True 0xA 0 (n div 0xA) = string_of_nat (unat (n div 0xA))"
     by(simp)
   show ?case
     apply(simp add: 1)
     apply(cases "n < 0xA")
      subgoal
      apply(subst(1) string_of_word.simps)
      apply(subst(1) string_of_nat.simps)
      apply(simp add: n_less_ten_unat)
-     by(simp add: not_wordlength_too_small ten_not_less_two string_of_word_single_atoi)
+       using lena apply(simp add: not_wordlength_too_small ten_not_less_two string_of_word_single_atoi)
+       done
     using sym[OF IH] apply(simp)
     apply(subst(1) string_of_word.simps)
     apply(simp)
     apply(subst(1) string_of_nat.simps)
     apply(simp)
-    apply(simp add: not_wordlength_too_small ten_not_less_two)
-    apply(subst string_of_word_single_atoi)
-     apply(rule Word.word_mod_less_divisor)
-     apply (auto simp add: not_less)
-    apply (metis \<open>10 \<le> n \<Longrightarrow> 10 \<le> unat n\<close> not_le string_of_nat.simps unat_div_ten unat_mod_ten)
+    apply (simp add: string_of_word_single_atoi Word.word_mod_less_divisor unat_div_ten unat_mod_ten)
+    using \<open>10 \<le> n \<Longrightarrow> 10 \<le> unat n\<close> not_wordlength_too_small apply (auto simp add: not_less)
     done
 qed
 
 (*TODO: one for all words?*)
 lemma dec_string_of_word0:
   "dec_string_of_word0 (w8:: 8 word) = string_of_nat (unat w8)"
   "dec_string_of_word0 (w16:: 16 word) = string_of_nat (unat w16)"
   "dec_string_of_word0 (w32:: 32 word) = string_of_nat (unat w32)"
   "dec_string_of_word0 (w64:: 64 word) = string_of_nat (unat w64)"
   "dec_string_of_word0 (w128:: 128 word) = string_of_nat (unat w128)"
   unfolding dec_string_of_word0_def
   using string_of_word_base_ten_zeropad by force+
 
 end
diff --git a/thys/IP_Addresses/NumberWang_IPv6.thy b/thys/IP_Addresses/NumberWang_IPv6.thy
--- a/thys/IP_Addresses/NumberWang_IPv6.thy
+++ b/thys/IP_Addresses/NumberWang_IPv6.thy
@@ -1,236 +1,233 @@
 theory NumberWang_IPv6
 imports 
   Word_Lib.Word_Lemmas
   Word_Lib.Word_Syntax
   Word_Lib.Reversed_Bit_Lists
 begin
 
 section\<open>Helper Lemmas for Low-Level Operations on Machine Words\<close>
 text\<open>Needed for IPv6 Syntax\<close>
 
 lemma length_drop_bl: "length (dropWhile Not (to_bl (of_bl bs))) \<le> length bs"
 proof -
   have length_takeWhile_Not_replicate_False:
     "length (takeWhile Not (replicate n False @ ls)) = n + length (takeWhile Not ls)"
   for n ls by(subst takeWhile_append2) simp+
   show ?thesis by(simp add: word_rep_drop dropWhile_eq_drop length_takeWhile_Not_replicate_False)
 qed
 
 lemma bl_drop_leading_zeros: 
       "(of_bl:: bool list \<Rightarrow> 'a::len word) (dropWhile Not bs) =
        (of_bl:: bool list \<Rightarrow> 'a::len word) bs"
 by(induction bs) simp_all
 
 
 lemma bl_length_drop_bound: assumes "length (dropWhile Not bs) \<le> n"
   shows "length (dropWhile Not (to_bl ((of_bl:: bool list \<Rightarrow> 'a::len word) bs))) \<le> n"
 proof -
   have bl_length_drop_twice: 
       "length (dropWhile Not (to_bl ((of_bl:: bool list \<Rightarrow> 'a::len word) (dropWhile Not bs)))) =
        length (dropWhile Not (to_bl ((of_bl:: bool list \<Rightarrow> 'a::len word) bs)))"
     by(simp add: bl_drop_leading_zeros)
   from length_drop_bl
   have *: "length (dropWhile Not (to_bl ((of_bl:: bool list \<Rightarrow> 'a::len word) bs))) \<le> length (dropWhile Not bs)"
    apply(rule dual_order.trans)
    apply(subst bl_length_drop_twice)
    ..
   show ?thesis
   apply(rule order.trans, rule *)
   using assms by(simp)
 qed
 
 context
   includes bit_operations_syntax
 begin
 
 lemma length_drop_mask_outer: fixes ip::"'a::len word"
   shows "LENGTH('a) - n' = len \<Longrightarrow> length (dropWhile Not (to_bl (ip AND (mask n << n') >> n'))) \<le> len"
   apply(subst word_and_mask_shiftl)
   apply(subst shiftl_shiftr1)
    apply(simp; fail)
   apply(simp)
   apply(subst and_mask)
   apply(simp add: word_size)
   apply(simp add: length_drop_mask)
   done
 
 lemma length_drop_mask_inner: fixes ip::"'a::len word"
   shows "n \<le> LENGTH('a) - n' \<Longrightarrow> length (dropWhile Not (to_bl (ip AND (mask n << n') >> n'))) \<le> n"
   apply(subst word_and_mask_shiftl)
   apply(subst shiftl_shiftr3)
    apply(simp; fail)
   apply(simp)
   apply(simp add: word_size)
   apply(simp add: mask_twice)
   apply(simp add: length_drop_mask)
   done
 
 end
 
 lemma mask128: "0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF = (mask 128 :: 'a::len word)"
-  by (simp add: mask_eq push_bit_of_1)
+  by (simp add: mask_numeral)
 
 
 (*-------------- things for ipv6 syntax round trip property two ------------------*)
 
 (*n small, m large*)
 lemma helper_masked_ucast_generic:
   fixes b::"16 word"
   assumes "n + 16 \<le> m" and "m < 128"
   shows "((ucast:: 16 word \<Rightarrow> 128 word) b << n) && (mask 16 << m) = 0"
 proof -
   have "x < 2 ^ (m - n)" if mnh2: "x < 0x10000"
     for x::"128 word"
   proof -
     from assms(1) have mnh3: "16 \<le> m - n" by fastforce
     have power_2_16_nat: "(16::nat) \<le> n \<Longrightarrow> (65535::nat) < 2 ^ n" if a:"16 \<le> n"for n
     proof -
       have power2_rule: "a \<le> b \<Longrightarrow> (2::nat)^a \<le> 2 ^ b" for a b by fastforce
       show ?thesis
        apply(subgoal_tac "65536 \<le> 2 ^ n")
         apply(subst Nat.less_eq_Suc_le)
         apply(simp; fail)
        apply(subgoal_tac "(65536::nat) = 2^16")
         subgoal using power2_rule \<open>16 \<le> n\<close> by presburger
        by(simp)
     qed
     have "65536 = unat (65536::128 word)" by auto
     moreover from mnh2 have "unat x <  unat (65536::128 word)" by(rule Word.unat_mono)
     ultimately have x: "unat x < 65536" by simp
     with mnh3 have "unat x < 2 ^ (m - n)" 
       using power_2_16_nat [of \<open>m - n\<close>] by simp
     with assms(2) show ?thesis by(subst word_less_nat_alt) simp
   qed
   hence mnhelper2: "(of_bl::bool list \<Rightarrow> 128 word) (to_bl b) < 2 ^ (m - n)"
     apply(subgoal_tac "(of_bl::bool list \<Rightarrow> 128 word) (to_bl b) < 2^(LENGTH(16))")
      apply(simp; fail)
     by(rule of_bl_length_less) simp+
   have mnhelper3: "(of_bl::bool list \<Rightarrow> 128 word) (to_bl b) * 2 ^ n < 2 ^ m"
     apply(rule div_lt_mult)
      apply(rule word_less_two_pow_divI)
        using assms by(simp_all add: mnhelper2 p2_gt_0)
 
-  from assms show ?thesis
-    apply(subst ucast_bl)+
-    apply(subst shiftl_of_bl)
-    apply(subst of_bl_append)
-    apply simp
-    apply(subst word_and_mask_shiftl)
-    apply(subst shiftr_div_2n_w)
-     subgoal by(simp add: word_size; fail)
-    apply(subst word_div_less)
-     subgoal by(rule mnhelper3)
-    apply simp
-    done
+     show ?thesis
+       apply (rule bit_word_eqI)
+       apply (simp only: bit_simps)
+       using assms(1)
+       apply auto
+       apply (transfer fixing: m n)
+       apply auto
+       done
 qed
 
 
 lemma unat_of_bl_128_16_less_helper:
   fixes b::"16 word"
   shows "unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) < 2^16"
 proof -
   from word_bl_Rep' have 1: "length (to_bl b) = 16" by simp
   have "unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) < 2^(length (to_bl b))"
     by(fact unat_of_bl_length)
   with 1 show ?thesis by auto
 qed
 lemma unat_of_bl_128_16_le_helper: "unat ((of_bl:: bool list \<Rightarrow> 128 word) (to_bl (b::16 word))) \<le> 65535"
 proof -
   from unat_of_bl_128_16_less_helper[of b] have
     "unat ((of_bl:: bool list \<Rightarrow> 128 word) (to_bl b)) < 65536" by simp 
   from Suc_leI[OF this] show ?thesis by simp
 qed
 
 
 (*reverse*)
  lemma helper_masked_ucast_reverse_generic:
    fixes b::"16 word"
    assumes "m + 16 \<le> n" and "n \<le> 128 - 16"
    shows "((ucast:: 16 word \<Rightarrow> 128 word) b << n) && (mask 16 << m) = 0"
  proof -
 
    have power_less_128_helper: "2 ^ n * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) < 2 ^ LENGTH(128)"
      if n: "n \<le> 128 - 16" for n
    proof -
      have help_mult: "n \<le> l \<Longrightarrow> 2 ^ n * x < 2 ^ l \<longleftrightarrow> x < 2 ^ (l - n)" for x::nat and l
        by (simp add: nat_mult_power_less_eq semiring_normalization_rules(7))
      from n show ?thesis
        apply(subst help_mult)
         subgoal by (simp)
        apply(rule order_less_le_trans)
         apply(rule unat_of_bl_128_16_less_helper)
        apply(rule Power.power_increasing)
         apply(simp_all)
        done
    qed
 
    have *: "2 ^ m * (2 ^ (n - m) * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b))) = 
             2 ^ n * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b))"
    proof(cases "unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) = 0")
    case True thus ?thesis by simp
    next
    case False
     have help_mult: "x \<noteq> 0 \<Longrightarrow> b * (c * x) = a * (x::nat)  \<longleftrightarrow> b * c = a" for x a b c by simp
     from assms show ?thesis
      apply(subst help_mult[OF False])
      apply(subst Power.monoid_mult_class.power_add[symmetric])
      apply(simp)
      done
    qed
 
   from assms have "unat ((2 ^ n)::128 word) * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) mod 2 ^ LENGTH(128) =
         2 ^ m * (2 ^ (n - m) * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) mod 2 ^ LENGTH(128))"
      apply(subst nat_mod_eq')
       subgoal apply(subst unat_power_lower)
        subgoal by(simp; fail)
       subgoal by (rule power_less_128_helper) simp
       done
      apply(subst nat_mod_eq')
       subgoal by(rule power_less_128_helper) simp
      apply(subst unat_power_lower)
       apply(simp; fail)
      apply(simp only: *)
      done
    hence ex_k: "\<exists>k. unat ((2 ^ n)::128 word) * unat ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b)) mod 2 ^ LENGTH(128) = 2 ^ m * k"
      by blast
 
    hence aligned: "is_aligned ((of_bl::bool list \<Rightarrow> 128 word) (to_bl b) << n) m"
      unfolding is_aligned_iff_dvd_nat
      unfolding dvd_def
      unfolding shiftl_t2n
      unfolding Word.unat_word_ariths(2)
      by assumption
 
    from assms have of_bl_to_bl_shift_mask: "((of_bl::bool list \<Rightarrow> 128 word) (to_bl b) << n) && mask (16 + m) = 0"
     using is_aligned_mask is_aligned_shiftl by force (*sledgehammer*)
 
    show ?thesis
     apply(subst ucast_bl)+
     apply(subst word_and_mask_shiftl)
     apply(subst aligned_shiftr_mask_shiftl)
      subgoal by (fact aligned)
     subgoal by (fact of_bl_to_bl_shift_mask)
     done
 qed
 
 
 lemma helper_masked_ucast_equal_generic:
   fixes b::"16 word"
   assumes "n \<le> 128 - 16"
   shows "ucast (((ucast:: 16 word \<Rightarrow> 128 word) b << n) && (mask 16 << n) >> n) = b"
 proof -
   have ucast_mask: "(ucast:: 16 word \<Rightarrow> 128 word) b && mask 16 = ucast b" 
-    by transfer (simp flip: take_bit_eq_mask)
+    by (simp only: flip: take_bit_eq_mask unsigned_take_bit_eq) (simp add: take_bit_word_eq_self)
   from assms have "ucast (((ucast:: 16 word \<Rightarrow> 128 word) b && mask (128 - n) && mask 16) && mask (128 - n)) = b"
-    by (auto simp add: bit_simps word_size intro!: bit_word_eqI)
+    by (simp only: take_bit_mask flip: take_bit_eq_mask unsigned_take_bit_eq)
+      (simp add: unsigned_ucast_eq take_bit_word_eq_self)
   thus ?thesis
   apply(subst word_and_mask_shiftl)
   apply(subst shiftl_shiftr3)
    apply(simp; fail)
   apply(simp)
   apply(subst shiftl_shiftr3)
     apply(simp_all add: word_size and.assoc)
   done
 qed
 
 end
diff --git a/thys/Word_Lib/Aligned.thy b/thys/Word_Lib/Aligned.thy
--- a/thys/Word_Lib/Aligned.thy
+++ b/thys/Word_Lib/Aligned.thy
@@ -1,1331 +1,1325 @@
 (*
  * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section "Word Alignment"
 
 theory Aligned
   imports
     "HOL-Library.Word"
     More_Word
-    Word_EqI
+    Bit_Shifts_Infix_Syntax
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 lift_definition is_aligned :: \<open>'a::len word \<Rightarrow> nat \<Rightarrow> bool\<close>
   is \<open>\<lambda>k n. 2 ^ n dvd take_bit LENGTH('a) k\<close>
   by simp
 
 lemma is_aligned_iff_udvd:
   \<open>is_aligned w n \<longleftrightarrow> 2 ^ n udvd w\<close>
   by transfer (simp flip: take_bit_eq_0_iff add: min_def)
 
 lemma is_aligned_iff_take_bit_eq_0:
   \<open>is_aligned w n \<longleftrightarrow> take_bit n w = 0\<close>
   by (simp add: is_aligned_iff_udvd take_bit_eq_0_iff exp_dvd_iff_exp_udvd)
 
 lemma is_aligned_iff_dvd_int:
   \<open>is_aligned ptr n \<longleftrightarrow> 2 ^ n dvd uint ptr\<close>
   by transfer simp
 
 lemma is_aligned_iff_dvd_nat:
   \<open>is_aligned ptr n \<longleftrightarrow> 2 ^ n dvd unat ptr\<close>
 proof -
   have \<open>unat ptr = nat \<bar>uint ptr\<bar>\<close>
     by transfer simp
   then have \<open>2 ^ n dvd unat ptr \<longleftrightarrow> 2 ^ n dvd uint ptr\<close>
     by (simp only: dvd_nat_abs_iff) simp
   then show ?thesis
     by (simp add: is_aligned_iff_dvd_int)
 qed
 
 lemma is_aligned_0 [simp]:
   \<open>is_aligned 0 n\<close>
   by transfer simp
 
 lemma is_aligned_at_0 [simp]:
   \<open>is_aligned w 0\<close>
   by transfer simp
 
 lemma is_aligned_beyond_length:
   \<open>is_aligned w n \<longleftrightarrow> w = 0\<close> if \<open>LENGTH('a) \<le> n\<close> for w :: \<open>'a::len word\<close>
   using that
   apply (simp add: is_aligned_iff_udvd)
   apply transfer
   apply auto
   done
 
 lemma is_alignedI [intro?]:
   \<open>is_aligned x n\<close> if \<open>x = 2 ^ n * k\<close> for x :: \<open>'a::len word\<close>
 proof (unfold is_aligned_iff_udvd)
   from that show \<open>2 ^ n udvd x\<close>
     using dvd_triv_left exp_dvd_iff_exp_udvd by blast
 qed
 
 lemma is_alignedE:
   fixes w :: \<open>'a::len word\<close>
   assumes \<open>is_aligned w n\<close>
   obtains q where \<open>w = 2 ^ n * word_of_nat q\<close> \<open>q < 2 ^ (LENGTH('a) - n)\<close>
 proof (cases \<open>n < LENGTH('a)\<close>)
   case False
   with assms have \<open>w = 0\<close>
     by (simp add: is_aligned_beyond_length)
   with that [of 0] show thesis
     by simp
 next
   case True
   moreover define m where \<open>m = LENGTH('a) - n\<close>
   ultimately have l: \<open>LENGTH('a) = n + m\<close> and \<open>m \<noteq> 0\<close>
     by simp_all
   from \<open>n < LENGTH('a)\<close> have *: \<open>unat (2 ^ n :: 'a word) = 2 ^ n\<close>
     by transfer simp
   from assms have \<open>2 ^ n udvd w\<close>
     by (simp add: is_aligned_iff_udvd)
   then obtain v :: \<open>'a word\<close>
     where \<open>unat w = unat (2 ^ n :: 'a word) * unat v\<close> ..
   moreover define q where \<open>q = unat v\<close>
   ultimately have unat_w: \<open>unat w = 2 ^ n * q\<close>
     by (simp add: *)
   then have \<open>word_of_nat (unat w) = (word_of_nat (2 ^ n * q) :: 'a word)\<close>
     by simp
   then have w: \<open>w = 2 ^ n * word_of_nat q\<close>
     by simp
   moreover have \<open>q < 2 ^ (LENGTH('a) - n)\<close>
   proof (rule ccontr)
     assume \<open>\<not> q < 2 ^ (LENGTH('a) - n)\<close>
     then have \<open>2 ^ (LENGTH('a) - n) \<le> q\<close>
       by simp
     then have \<open>2 ^ LENGTH('a) \<le> 2 ^ n * q\<close>
       by (simp add: l power_add)
     with unat_w [symmetric] show False
       by (metis le_antisym nat_less_le unsigned_less) 
   qed
   ultimately show thesis
     using that by blast
 qed
 
 lemma is_alignedE' [elim?]:
   fixes w :: \<open>'a::len word\<close>
   assumes \<open>is_aligned w n\<close>
   obtains q where \<open>w = push_bit n (word_of_nat q)\<close> \<open>q < 2 ^ (LENGTH('a) - n)\<close>
 proof -
   from assms
   obtain q where \<open>w = 2 ^ n * word_of_nat q\<close> \<open>q < 2 ^ (LENGTH('a) - n)\<close>
     by (rule is_alignedE)
   then have \<open>w = push_bit n (word_of_nat q)\<close>
     by (simp add: push_bit_eq_mult)
   with that show thesis
     using \<open>q < 2 ^ (LENGTH('a) - n)\<close> .
 qed
 
 lemma is_aligned_mask:
   \<open>is_aligned w n \<longleftrightarrow> w AND mask n = 0\<close>
   by (simp add: is_aligned_iff_take_bit_eq_0 take_bit_eq_mask)
 
 lemma is_aligned_imp_not_bit:
   \<open>\<not> bit w m\<close> if \<open>is_aligned w n\<close> and \<open>m < n\<close>
   for w :: \<open>'a::len word\<close>
 proof -
   from \<open>is_aligned w n\<close>
   obtain q where \<open>w = push_bit n (word_of_nat q)\<close> \<open>q < 2 ^ (LENGTH('a) - n)\<close> ..
   moreover have \<open>\<not> bit (push_bit n (word_of_nat q :: 'a word)) m\<close>
     using \<open>m < n\<close> by (simp add: bit_simps)
   ultimately show ?thesis
     by simp
 qed
 
 lemma is_aligned_weaken:
   "\<lbrakk> is_aligned w x; x \<ge> y \<rbrakk> \<Longrightarrow> is_aligned w y"
   unfolding is_aligned_iff_dvd_nat
   by (erule dvd_trans [rotated]) (simp add: le_imp_power_dvd)
 
 lemma is_alignedE_pre:
   fixes w::"'a::len word"
   assumes aligned: "is_aligned w n"
   shows        rl: "\<exists>q. w = 2 ^ n * (of_nat q) \<and> q < 2 ^ (LENGTH('a) - n)"
   using aligned is_alignedE by blast
 
 lemma aligned_add_aligned:
   fixes x::"'a::len word"
   assumes aligned1: "is_aligned x n"
   and     aligned2: "is_aligned y m"
   and           lt: "m \<le> n"
   shows   "is_aligned (x + y) m"
 proof cases
   assume nlt: "n < LENGTH('a)"
   show ?thesis
     unfolding is_aligned_iff_dvd_nat dvd_def
   proof -
     from aligned2 obtain q2 where yv: "y = 2 ^ m * of_nat q2"
       and q2v: "q2 < 2 ^ (LENGTH('a) - m)"
       by (auto elim: is_alignedE)
 
     from lt obtain k where kv: "m + k = n" by (auto simp: le_iff_add)
     with aligned1 obtain q1 where xv: "x = 2 ^ (m + k) * of_nat q1"
       and q1v: "q1 < 2 ^ (LENGTH('a) - (m + k))"
       by (auto elim: is_alignedE)
 
     have l1: "2 ^ (m + k) * q1 < 2 ^ LENGTH('a)"
       by (rule nat_less_power_trans [OF q1v])
          (subst kv, rule order_less_imp_le [OF nlt])
 
     have l2: "2 ^ m * q2 < 2 ^ LENGTH('a)"
       by (rule nat_less_power_trans [OF q2v],
           rule order_less_imp_le [OF order_le_less_trans])
          fact+
 
     have "x = of_nat (2 ^ (m + k) *  q1)" using xv
       by simp
 
     moreover have "y = of_nat (2 ^ m * q2)" using yv
       by simp
 
     ultimately have upls: "unat x + unat y = 2 ^ m * (2 ^ k * q1 + q2)"
     proof -
       have f1: "unat x = 2 ^ (m + k) * q1"
         using q1v unat_mult_power_lem xv by blast
       have "unat y = 2 ^ m * q2"
         using q2v unat_mult_power_lem yv by blast
       then show ?thesis
         using f1 by (simp add: power_add semiring_normalization_rules(34))
     qed
 
     (* (2 ^ k * q1 + q2) *)
     show "\<exists>d. unat (x + y) = 2 ^ m * d"
     proof (cases "unat x + unat y < 2 ^ LENGTH('a)")
       case True
 
       have "unat (x + y) = unat x + unat y"
         by (subst unat_plus_if', rule if_P) fact
 
       also have "\<dots> = 2 ^ m * (2 ^ k * q1 + q2)" by (rule upls)
       finally show ?thesis ..
     next
       case False
       then have "unat (x + y) = (unat x + unat y) mod 2 ^ LENGTH('a)"
         by (subst unat_word_ariths(1)) simp
 
       also have "\<dots> = (2 ^ m * (2 ^ k * q1 + q2)) mod 2 ^ LENGTH('a)"
         by (subst upls, rule refl)
 
       also
       have "\<dots> = 2 ^ m * ((2 ^ k * q1 +  q2) mod 2 ^ (LENGTH('a) - m))"
       proof -
         have "m \<le> len_of (TYPE('a))"
           by (meson le_trans less_imp_le_nat lt nlt)
         then show ?thesis
           by (metis mult_mod_right ordered_cancel_comm_monoid_diff_class.add_diff_inverse power_add)
       qed
 
       finally show ?thesis ..
     qed
   qed
 next
   assume "\<not> n < LENGTH('a)"
   with assms
   show ?thesis
     by (simp add: is_aligned_mask not_less take_bit_eq_mod power_overflow word_arith_nat_defs(7) flip: take_bit_eq_mask)
 qed
 
 corollary aligned_sub_aligned:
   "\<lbrakk>is_aligned (x::'a::len word) n; is_aligned y m; m \<le> n\<rbrakk>
    \<Longrightarrow> is_aligned (x - y) m"
   apply (simp del: add_uminus_conv_diff add:diff_conv_add_uminus)
   apply (erule aligned_add_aligned, simp_all)
   apply (erule is_alignedE)
   apply (rule_tac k="- of_nat q" in is_alignedI)
   apply simp
   done
 
 lemma is_aligned_shift:
   fixes k::"'a::len word"
-  shows "is_aligned (push_bit m k) m"
+  shows "is_aligned (k << m) m"
 proof cases
   assume mv: "m < LENGTH('a)"
   from mv obtain q where mq: "m + q = LENGTH('a)" and "0 < q"
     by (auto dest: less_imp_add_positive)
 
   have "(2::nat) ^ m dvd unat (push_bit m k)"
   proof
     have kv: "(unat k div 2 ^ q) * 2 ^ q + unat k mod 2 ^ q = unat k"
       by (rule div_mult_mod_eq)
 
     have "unat (push_bit m k) = unat (2 ^ m * k)"
       by (simp add: push_bit_eq_mult ac_simps)
     also have "\<dots> = (2 ^ m * unat k) mod (2 ^ LENGTH('a))" using mv
       by (simp add: unat_word_ariths(2))
     also have "\<dots> = 2 ^ m * (unat k mod 2 ^ q)"
       by (subst mq [symmetric], subst power_add, subst mod_mult2_eq) simp
     finally show "unat (push_bit m k) = 2 ^ m * (unat k mod 2 ^ q)" .
   qed
-
-  then show ?thesis by (unfold is_aligned_iff_dvd_nat)
+  then show ?thesis by (unfold is_aligned_iff_dvd_nat shiftl_def)
 next
   assume "\<not> m < LENGTH('a)"
   then show ?thesis
-    by (simp add: not_less power_overflow is_aligned_mask word_size)
+    by (simp add: not_less power_overflow is_aligned_mask word_size shiftl_def)
 qed
 
-lemma word_mod_by_0: "k mod (0::'a::len word) = k"
-  by (simp add: word_arith_nat_mod)
-
 lemma aligned_mod_eq_0:
   fixes p::"'a::len word"
   assumes al: "is_aligned p sz"
   shows   "p mod 2 ^ sz = 0"
 proof cases
   assume szv: "sz < LENGTH('a)"
   with al
   show ?thesis
     unfolding is_aligned_iff_dvd_nat
     by (simp add: and_mask_dvd_nat p2_gt_0 word_mod_2p_is_mask)
 next
   assume "\<not> sz < LENGTH('a)"
   with al show ?thesis
     by (simp add: is_aligned_mask flip: take_bit_eq_mask take_bit_eq_mod)
 qed
 
 lemma is_aligned_triv: "is_aligned (2 ^ n ::'a::len word) n"
   by (rule is_alignedI [where k = 1], simp)
 
 lemma is_aligned_mult_triv1: "is_aligned (2 ^ n * x  ::'a::len word) n"
   by (rule is_alignedI [OF refl])
 
 lemma is_aligned_mult_triv2: "is_aligned (x * 2 ^ n ::'a::len word) n"
   by (subst mult.commute, simp add: is_aligned_mult_triv1)
 
 lemma word_power_less_0_is_0:
   fixes x :: "'a::len word"
   shows "x < a ^ 0 \<Longrightarrow> x = 0" by simp
 
 lemma is_aligned_no_wrap:
   fixes off :: "'a::len word"
   fixes ptr :: "'a::len word"
   assumes al: "is_aligned ptr sz"
   and    off: "off < 2 ^ sz"
   shows  "unat ptr + unat off < 2 ^ LENGTH('a)"
 proof -
   have szv: "sz < LENGTH('a)"
   using off p2_gt_0 word_neq_0_conv by fastforce
 
   from al obtain q where ptrq: "ptr = 2 ^ sz * of_nat q" and
     qv: "q < 2 ^ (LENGTH('a) - sz)" by (auto elim: is_alignedE)
 
   show ?thesis
   proof (cases "sz = 0")
     case True
     then show ?thesis using off ptrq qv
       by simp
   next
     case False
     then have sne: "0 < sz" ..
 
     show ?thesis
     proof -
       have uq: "unat (of_nat q ::'a::len word) = q"
         apply (subst unat_of_nat)
         apply (rule mod_less)
         apply (rule order_less_trans [OF qv])
         apply (rule power_strict_increasing [OF diff_less [OF sne]])
          apply (simp_all)
         done
 
       have uptr: "unat ptr = 2 ^ sz * q"
         apply (subst ptrq)
         apply (subst iffD1 [OF unat_mult_lem])
          apply (subst unat_power_lower [OF szv])
          apply (subst uq)
          apply (rule nat_less_power_trans [OF qv order_less_imp_le [OF szv]])
         apply (subst uq)
         apply (subst unat_power_lower [OF szv])
         apply simp
         done
 
       show "unat ptr + unat off < 2 ^ LENGTH('a)" using szv
         apply (subst uptr)
         apply (subst mult.commute, rule nat_add_offset_less [OF _ qv])
         apply (rule order_less_le_trans [OF unat_mono [OF off] order_eq_refl])
          apply simp_all
         done
     qed
   qed
 qed
 
 lemma is_aligned_no_wrap':
   fixes ptr :: "'a::len word"
   assumes al: "is_aligned ptr sz"
   and    off: "off < 2 ^ sz"
   shows  "ptr \<le> ptr + off"
   by (subst no_plus_overflow_unat_size, subst word_size, rule is_aligned_no_wrap) fact+
 
 lemma is_aligned_no_overflow':
   fixes p :: "'a::len word"
   assumes al: "is_aligned p n"
   shows "p \<le> p + (2 ^ n - 1)"
 proof cases
   assume "n<LENGTH('a)"
   with al
   have "2^n - (1::'a::len word) < 2^n"
     by (simp add: word_less_nat_alt unat_sub_if_size)
   with al
   show ?thesis by (rule is_aligned_no_wrap')
 next
   assume "\<not> n<LENGTH('a)"
   with al
   show ?thesis
   by (simp add: not_less power_overflow is_aligned_mask mask_2pm1)
 qed
 
 lemma is_aligned_no_overflow:
   "is_aligned ptr sz \<Longrightarrow> ptr \<le> ptr + 2^sz - 1"
   by (drule is_aligned_no_overflow') (simp add: field_simps)
 
 lemma replicate_not_True:
   "\<And>n. xs = replicate n False \<Longrightarrow> True \<notin> set xs"
   by (induct xs) auto
 
 lemma map_zip_replicate_False_xor:
   "n = length xs \<Longrightarrow> map (\<lambda>(x, y). x = (\<not> y)) (zip xs (replicate n False)) = xs"
   by (induct xs arbitrary: n, auto)
 
 lemma drop_minus_lem:
   "\<lbrakk> n \<le> length xs; 0 < n; n' = length xs \<rbrakk> \<Longrightarrow> drop (n' - n) xs = rev xs ! (n - 1)  # drop (Suc (n' - n)) xs"
 proof (induct xs arbitrary: n n')
   case Nil then show ?case by simp
 next
   case (Cons y ys)
   from Cons.prems
   show ?case
     apply simp
     apply (cases "n = Suc (length ys)")
      apply (simp add: nth_append)
     apply (simp add: Suc_diff_le Cons.hyps nth_append)
     apply clarsimp
     apply arith
     done
 qed
 
 lemma drop_minus:
   "\<lbrakk> n < length xs; n' = length xs \<rbrakk> \<Longrightarrow> drop (n' - Suc n) xs = rev xs ! n  # drop (n' - n) xs"
   apply (subst drop_minus_lem)
      apply simp
     apply simp
    apply simp
   apply simp
   apply (cases "length xs", simp)
   apply (simp add: Suc_diff_le)
   done
 
 lemma aligned_add_xor:
   \<open>(x + 2 ^ n) XOR 2 ^ n = x\<close>
   if al: \<open>is_aligned (x::'a::len word) n'\<close> and le: \<open>n < n'\<close>
 proof -
   have \<open>\<not> bit x n\<close>
     using that by (rule is_aligned_imp_not_bit)
   then have \<open>x + 2 ^ n = x OR 2 ^ n\<close>
     by (subst disjunctive_add) (auto simp add: bit_simps disjunctive_add)
   moreover have \<open>(x OR 2 ^ n) XOR 2 ^ n = x\<close>
     by (rule bit_word_eqI) (auto simp add: bit_simps \<open>\<not> bit x n\<close>)
   ultimately show ?thesis
     by simp
 qed
 
 lemma is_aligned_add_mult_multI:
   fixes p :: "'a::len word"
   shows "\<lbrakk>is_aligned p m; n \<le> m; n' = n\<rbrakk> \<Longrightarrow> is_aligned (p + x * 2 ^ n * z) n'"
   apply (erule aligned_add_aligned)
   apply (auto intro: is_alignedI [where k="x*z"])
   done
 
 lemma is_aligned_add_multI:
   fixes p :: "'a::len word"
   shows "\<lbrakk>is_aligned p m; n \<le> m; n' = n\<rbrakk> \<Longrightarrow> is_aligned (p + x * 2 ^ n) n'"
   apply (erule aligned_add_aligned)
   apply (auto intro: is_alignedI [where k="x"])
   done
 
 lemma is_aligned_no_wrap''':
   fixes ptr :: "'a::len word"
   shows"\<lbrakk> is_aligned ptr sz; sz < LENGTH('a); off < 2 ^ sz \<rbrakk>
          \<Longrightarrow> unat ptr + off < 2 ^ LENGTH('a)"
   apply (drule is_aligned_no_wrap[where off="of_nat off"])
    apply (simp add: word_less_nat_alt)
    apply (erule order_le_less_trans[rotated])
   apply (simp add: take_bit_eq_mod unsigned_of_nat)
   apply (subst(asm) unat_of_nat_len)
    apply (erule order_less_trans)
    apply (erule power_strict_increasing)
    apply simp
   apply assumption
   done
 
 lemma is_aligned_get_word_bits:
   fixes p :: "'a::len word"
   shows "\<lbrakk> is_aligned p n; \<lbrakk> is_aligned p n; n < LENGTH('a) \<rbrakk> \<Longrightarrow> P;
            \<lbrakk> p = 0; n \<ge> LENGTH('a) \<rbrakk> \<Longrightarrow> P \<rbrakk> \<Longrightarrow> P"
   apply (cases "n < LENGTH('a)")
    apply simp
   apply simp
   apply (erule meta_mp)
   apply (simp add: is_aligned_mask power_add power_overflow not_less
     flip: take_bit_eq_mask)
   apply (metis take_bit_length_eq take_bit_of_0 take_bit_tightened)
   done
 
 lemma aligned_small_is_0:
   "\<lbrakk> is_aligned x n; x < 2 ^ n \<rbrakk> \<Longrightarrow> x = 0"
   by (simp add: is_aligned_mask less_mask_eq)
 
 corollary is_aligned_less_sz:
   "\<lbrakk>is_aligned a sz; a \<noteq> 0\<rbrakk> \<Longrightarrow> \<not> a < 2 ^ sz"
   by (rule notI, drule(1) aligned_small_is_0, erule(1) notE)
 
 lemma aligned_at_least_t2n_diff:
   "\<lbrakk>is_aligned x n; is_aligned y n; x < y\<rbrakk> \<Longrightarrow> x \<le> y - 2 ^ n"
   apply (erule is_aligned_get_word_bits[where p=y])
    apply (rule ccontr)
    apply (clarsimp simp: linorder_not_le)
    apply (subgoal_tac "y - x = 0")
     apply clarsimp
    apply (rule aligned_small_is_0)
     apply (erule(1) aligned_sub_aligned)
     apply simp
    apply unat_arith
   apply simp
   done
 
 lemma is_aligned_no_overflow'':
   "\<lbrakk>is_aligned x n; x + 2 ^ n \<noteq> 0\<rbrakk> \<Longrightarrow> x \<le> x + 2 ^ n"
   apply (frule is_aligned_no_overflow')
   apply (erule order_trans)
   apply (simp add: field_simps)
   apply (erule word_sub_1_le)
   done
 
 lemma is_aligned_bitI:
   \<open>is_aligned p m\<close> if \<open>\<And>n. n < m \<Longrightarrow> \<not> bit p n\<close>
   apply (simp add: is_aligned_mask)
   apply (rule bit_word_eqI)
   using that
   apply (auto simp add: bit_simps)
   done
 
-lemma is_aligned_nth [word_eqI_simps]:
+lemma is_aligned_nth:
   "is_aligned p m = (\<forall>n < m. \<not> bit p n)"
   apply (auto intro: is_aligned_bitI simp add: is_aligned_mask bit_eq_iff)
    apply (auto simp: bit_simps)
   using bit_imp_le_length not_less apply blast
   done
 
 lemma range_inter:
   "({a..b} \<inter> {c..d} = {}) = (\<forall>x. \<not>(a \<le> x \<and> x \<le> b \<and> c \<le> x \<and> x \<le> d))"
   by auto
 
 lemma aligned_inter_non_empty:
   "\<lbrakk> {p..p + (2 ^ n - 1)} \<inter> {p..p + 2 ^ m - 1} = {};
      is_aligned p n; is_aligned p m\<rbrakk> \<Longrightarrow> False"
   apply (clarsimp simp only: range_inter)
   apply (erule_tac x=p in allE)
   apply simp
   apply (erule impE)
    apply (erule is_aligned_no_overflow')
   apply (erule notE)
   apply (erule is_aligned_no_overflow)
   done
 
 lemma not_aligned_mod_nz:
   assumes al: "\<not> is_aligned a n"
   shows "a mod 2 ^ n \<noteq> 0"
   apply (rule ccontr)
   using al apply (rule notE)
   apply simp
   apply (rule is_alignedI [of _ _ \<open>a div 2 ^ n\<close>])
   apply (metis add.right_neutral mult.commute word_mod_div_equality)
   done
 
 lemma nat_add_offset_le:
   fixes x :: nat
   assumes yv: "y \<le> 2 ^ n"
   and     xv: "x < 2 ^ m"
   and     mn: "sz = m + n"
   shows   "x * 2 ^ n + y \<le> 2 ^ sz"
 proof (subst mn)
   from yv obtain qy where "y + qy = 2 ^ n"
     by (auto simp: le_iff_add)
 
   have "x * 2 ^ n + y \<le> x * 2 ^ n + 2 ^ n"
     using yv xv by simp
   also have "\<dots> = (x + 1) * 2 ^ n" by simp
   also have "\<dots> \<le> 2 ^ (m + n)" using xv
     by (subst power_add) (rule mult_le_mono1, simp)
   finally show "x * 2 ^ n + y \<le> 2 ^ (m + n)" .
 qed
 
 lemma is_aligned_no_wrap_le:
   fixes ptr::"'a::len word"
   assumes al: "is_aligned ptr sz"
   and    szv: "sz < LENGTH('a)"
   and    off: "off \<le> 2 ^ sz"
   shows  "unat ptr + off \<le> 2 ^ LENGTH('a)"
 proof -
   from al obtain q where ptrq: "ptr = 2 ^ sz * of_nat q" and
     qv: "q < 2 ^ (LENGTH('a) - sz)" by (auto elim: is_alignedE)
 
   show ?thesis
   proof (cases "sz = 0")
     case True
     then show ?thesis using off ptrq qv
       by (auto simp add: le_Suc_eq Suc_le_eq) (simp add: le_less)
   next
     case False
     then have sne: "0 < sz" ..
 
     show ?thesis
     proof -
       have uq: "unat (of_nat q :: 'a word) = q"
         apply (subst unat_of_nat)
         apply (rule mod_less)
         apply (rule order_less_trans [OF qv])
         apply (rule power_strict_increasing [OF diff_less [OF sne]])
         apply simp_all
         done
 
       have uptr: "unat ptr = 2 ^ sz * q"
         apply (subst ptrq)
         apply (subst iffD1 [OF unat_mult_lem])
         apply (subst unat_power_lower [OF szv])
         apply (subst uq)
         apply (rule nat_less_power_trans [OF qv order_less_imp_le [OF szv]])
         apply (subst uq)
         apply (subst unat_power_lower [OF szv])
         apply simp
         done
 
       show "unat ptr + off \<le> 2 ^ LENGTH('a)" using szv
         apply (subst uptr)
         apply (subst mult.commute, rule nat_add_offset_le [OF off qv])
         apply simp
         done
     qed
   qed
 qed
 
 lemma is_aligned_neg_mask:
   "m \<le> n \<Longrightarrow> is_aligned (x AND NOT (mask n)) m"
   by (rule is_aligned_bitI) (simp add: bit_simps)
 
 lemma unat_minus:
   "unat (- (x :: 'a :: len word)) = (if x = 0 then 0 else 2 ^ size x - unat x)"
   using unat_sub_if_size[where x="2 ^ size x" and y=x]
   by (simp add: unat_eq_0 word_size)
 
 lemma is_aligned_minus:
   \<open>is_aligned (- p) n\<close> if \<open>is_aligned p n\<close> for p :: \<open>'a::len word\<close>
   using that
   apply (cases \<open>n < LENGTH('a)\<close>)
   apply (simp_all add: not_less is_aligned_beyond_length)
   apply transfer
   apply (simp flip: take_bit_eq_0_iff)
   apply (subst take_bit_minus [symmetric])
   apply simp
   done
 
 lemma add_mask_lower_bits:
   "\<lbrakk>is_aligned (x :: 'a :: len word) n;
     \<forall>n' \<ge> n. n' < LENGTH('a) \<longrightarrow> \<not> bit p n'\<rbrakk> \<Longrightarrow> x + p AND NOT (mask n) = x"
   apply (subst word_plus_and_or_coroll)
    apply (rule word_eqI)
    apply (clarsimp simp: word_size is_aligned_nth)
    apply (erule_tac x=na in allE)+
    apply (simp add: bit_simps)
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps not_less word_size)
   apply (metis is_aligned_nth not_le)
   done
 
 lemma is_aligned_andI1:
   "is_aligned x n \<Longrightarrow> is_aligned (x AND y) n"
   by (simp add: is_aligned_nth bit_simps)
 
 lemma is_aligned_andI2:
   "is_aligned y n \<Longrightarrow> is_aligned (x AND y) n"
   by (simp add: is_aligned_nth bit_simps)
 
 lemma is_aligned_shiftl:
-  "is_aligned w (n - m) \<Longrightarrow> is_aligned (push_bit m w) n"
+  "is_aligned w (n - m) \<Longrightarrow> is_aligned (w << m) n"
   by (simp add: is_aligned_nth bit_simps)
 
 lemma is_aligned_shiftr:
-  "is_aligned w (n + m) \<Longrightarrow> is_aligned (drop_bit m w) n"
+  "is_aligned w (n + m) \<Longrightarrow> is_aligned (w >> m) n"
   by (simp add: is_aligned_nth bit_simps)
 
 lemma is_aligned_shiftl_self:
-  "is_aligned (push_bit n p) n"
+  "is_aligned (p << n) n"
   by (rule is_aligned_shift)
 
 lemma is_aligned_neg_mask_eq:
   "is_aligned p n \<Longrightarrow> p AND NOT (mask n) = p"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps is_aligned_nth)
   done
 
 lemma is_aligned_shiftr_shiftl:
-  "is_aligned w n \<Longrightarrow> push_bit n (drop_bit n w) = w"
+  "is_aligned w n \<Longrightarrow> w >> n << n = w"
   apply (rule bit_word_eqI)
-  apply (auto simp add: bit_simps is_aligned_nth)
-  using not_le_imp_less apply blast
-  apply (metis add_diff_inverse_nat)
+  apply (auto simp add: bit_simps is_aligned_nth intro: ccontr)
+  apply (subst add_diff_inverse_nat)
+   apply (auto intro: ccontr)
   done
 
 lemma aligned_shiftr_mask_shiftl:
-  "is_aligned x n \<Longrightarrow> push_bit n (drop_bit n x AND mask v) = x AND mask (v + n)"
+  "is_aligned x n \<Longrightarrow> ((x >> n) AND mask v) << n = x AND mask (v + n)"
   apply (rule word_eqI)
   apply (simp add: word_size bit_simps)
   apply (subgoal_tac "\<forall>m. bit x m \<longrightarrow> m \<ge> n")
    apply auto[1]
   apply (clarsimp simp: is_aligned_mask)
   apply (drule_tac x=m in word_eqD)
   apply (frule test_bit_size)
   apply (simp add: word_size bit_simps)
   done
 
 lemma mask_zero:
   "is_aligned x a \<Longrightarrow> x AND mask a = 0"
   by (metis is_aligned_mask)
 
 lemma is_aligned_neg_mask_eq_concrete:
   "\<lbrakk> is_aligned p n; msk AND NOT (mask n) = NOT (mask n) \<rbrakk>
    \<Longrightarrow> p AND msk = p"
   by (metis word_bw_assocs(1) word_bw_comms(1) is_aligned_neg_mask_eq)
 
 lemma is_aligned_and_not_zero:
   "\<lbrakk> is_aligned n k; n \<noteq> 0 \<rbrakk> \<Longrightarrow> 2 ^ k \<le> n"
   using is_aligned_less_sz leI by blast
 
 lemma is_aligned_and_2_to_k:
   "(n AND 2 ^ k - 1) = 0 \<Longrightarrow> is_aligned (n :: 'a :: len word) k"
   by (simp add: is_aligned_mask mask_eq_decr_exp)
 
 lemma is_aligned_power2:
   "b \<le> a \<Longrightarrow> is_aligned (2 ^ a) b"
   by (metis is_aligned_triv is_aligned_weaken)
 
 lemma aligned_sub_aligned':
   "\<lbrakk> is_aligned (a :: 'a :: len word) n; is_aligned b n; n < LENGTH('a) \<rbrakk>
    \<Longrightarrow> is_aligned (a - b) n"
   by (simp add: aligned_sub_aligned)
 
 lemma is_aligned_neg_mask_weaken:
   "\<lbrakk> is_aligned p n; m \<le> n \<rbrakk> \<Longrightarrow> p AND NOT (mask m) = p"
    using is_aligned_neg_mask_eq is_aligned_weaken by blast
 
 lemma is_aligned_neg_mask2 [simp]:
   "is_aligned (a AND NOT (mask n)) n"
   by (rule is_aligned_bitI) (simp add: bit_simps)
 
 lemma is_aligned_0':
   "is_aligned 0 n"
   by (fact is_aligned_0)
 
 lemma aligned_add_offset_no_wrap:
   fixes off :: "('a::len) word"
   and     x :: "'a word"
   assumes al: "is_aligned x sz"
   and   offv: "off < 2 ^ sz"
   shows  "unat x + unat off < 2 ^ LENGTH('a)"
 proof cases
   assume szv: "sz < LENGTH('a)"
   from al obtain k where xv: "x = 2 ^ sz * (of_nat k)"
     and kl: "k < 2 ^ (LENGTH('a) - sz)"
     by (auto elim: is_alignedE)
 
   show ?thesis using szv
     apply (subst xv)
     apply (subst unat_mult_power_lem[OF kl])
     apply (subst mult.commute, rule nat_add_offset_less)
       apply (rule less_le_trans[OF unat_mono[OF offv, simplified]])
       apply (erule eq_imp_le[OF unat_power_lower])
      apply (rule kl)
     apply simp
    done
 next
   assume "\<not> sz < LENGTH('a)"
   with offv show ?thesis by (simp add: not_less power_overflow )
 qed
 
 lemma aligned_add_offset_mod:
   fixes x :: "('a::len) word"
   assumes al: "is_aligned x sz"
   and     kv: "k < 2 ^ sz"
   shows   "(x + k) mod 2 ^ sz = k"
 proof cases
   assume szv: "sz < LENGTH('a)"
 
   have ux: "unat x + unat k < 2 ^ LENGTH('a)"
     by (rule aligned_add_offset_no_wrap) fact+
 
   show ?thesis using al szv
     apply (simp flip: take_bit_eq_mod)
     apply (rule bit_word_eqI)
     apply (auto simp add: bit_simps)
     apply (metis assms(2) bit_or_iff is_aligned_mask is_aligned_nth leD less_mask_eq word_and_le1 word_bw_lcs(1) word_neq_0_conv word_plus_and_or_coroll)
      apply (meson assms(2) leI less_2p_is_upper_bits_unset)
     apply (metis assms(2) bit_disjunctive_add_iff bit_imp_le_length bit_push_bit_iff is_alignedE' less_2p_is_upper_bits_unset)
     done
 next
   assume "\<not> sz < LENGTH('a)"
   with al show ?thesis
     by (simp add: not_less power_overflow is_aligned_mask mask_eq_decr_exp
                   word_mod_by_0)
 qed
 
 lemma aligned_neq_into_no_overlap:
   fixes x :: "'a::len word"
   assumes neq: "x \<noteq> y"
   and     alx: "is_aligned x sz"
   and     aly: "is_aligned y sz"
   shows  "{x .. x + (2 ^ sz - 1)} \<inter> {y .. y + (2 ^ sz - 1)} = {}"
 proof cases
   assume szv: "sz < LENGTH('a)"
   show ?thesis
   proof (rule equals0I, clarsimp)
     fix z
     assume xb: "x \<le> z" and xt: "z \<le> x + (2 ^ sz - 1)"
       and yb: "y \<le> z" and yt: "z \<le> y + (2 ^ sz - 1)"
 
     have rl: "\<And>(p::'a word) k w. \<lbrakk>uint p + uint k < 2 ^ LENGTH('a); w = p + k; w \<le> p + (2 ^ sz - 1) \<rbrakk>
       \<Longrightarrow> k < 2 ^ sz"
       apply -
       apply simp
       apply (subst (asm) add.commute, subst (asm) add.commute, drule word_plus_mcs_4)
        apply (subst add.commute, subst no_plus_overflow_uint_size)
        apply transfer
       apply simp
       apply (auto simp add: le_less power_2_ge_iff szv)
       apply (metis le_less_trans mask_eq_decr_exp mask_lt_2pn order_less_imp_le szv)
       done
 
     from xb obtain kx where
       kx: "z = x + kx" and
       kxl: "uint x + uint kx < 2 ^ LENGTH('a)"
       by (clarsimp dest!: word_le_exists')
 
     from yb obtain ky where
       ky: "z = y + ky" and
       kyl: "uint y + uint ky < 2 ^ LENGTH('a)"
       by (clarsimp dest!: word_le_exists')
 
     have "x = y"
     proof -
       have "kx = z mod 2 ^ sz"
       proof (subst kx, rule sym, rule aligned_add_offset_mod)
         show "kx < 2 ^ sz" by (rule rl) fact+
       qed fact+
 
       also have "\<dots> = ky"
       proof (subst ky, rule aligned_add_offset_mod)
         show "ky < 2 ^ sz"
           using kyl ky yt by (rule rl)
       qed fact+
 
       finally have kxky: "kx = ky" .
       moreover have "x + kx = y + ky" by (simp add: kx [symmetric] ky [symmetric])
       ultimately show ?thesis by simp
     qed
     then show False using neq by simp
   qed
 next
   assume "\<not> sz < LENGTH('a)"
   with neq alx aly
   have False by (simp add: is_aligned_mask mask_eq_decr_exp power_overflow)
   then show ?thesis ..
 qed
 
 lemma is_aligned_add_helper:
   "\<lbrakk> is_aligned p n; d < 2 ^ n \<rbrakk>
      \<Longrightarrow> (p + d AND mask n = d) \<and> (p + d AND (NOT (mask n)) = p)"
   apply (subst (asm) is_aligned_mask)
   apply (drule less_mask_eq)
   apply (rule context_conjI)
    apply (subst word_plus_and_or_coroll)
     apply (simp_all flip: take_bit_eq_mask)
    apply (metis take_bit_eq_mask word_bw_lcs(1) word_log_esimps(1))
   apply (metis add.commute add_left_imp_eq take_bit_eq_mask word_plus_and_or_coroll2)
   done
 
 lemmas mask_inner_mask = mask_eqs(1)
 
 lemma mask_add_aligned:
   "is_aligned p n \<Longrightarrow> (p + q) AND mask n = q AND mask n"
   apply (simp add: is_aligned_mask)
   apply (subst mask_inner_mask [symmetric])
   apply simp
   done
 
 lemma mask_out_add_aligned:
   assumes al: "is_aligned p n"
   shows "p + (q AND NOT (mask n)) = (p + q) AND NOT (mask n)"
   using mask_add_aligned [OF al]
   by (simp add: mask_out_sub_mask)
 
 lemma is_aligned_add_or:
   "\<lbrakk>is_aligned p n; d < 2 ^ n\<rbrakk> \<Longrightarrow> p + d = p OR d"
   apply (subst disjunctive_add, simp_all)
   apply (clarsimp simp: is_aligned_nth less_2p_is_upper_bits_unset)
   subgoal for m
     apply (cases \<open>m < n\<close>)
      apply (auto simp add: not_less dest: bit_imp_possible_bit)
     done
   done
 
 lemma not_greatest_aligned:
   "\<lbrakk> x < y; is_aligned x n; is_aligned y n \<rbrakk> \<Longrightarrow> x + 2 ^ n \<noteq> 0"
   by (metis NOT_mask add_diff_cancel_right' diff_0 is_aligned_neg_mask_eq not_le word_and_le1)
 
 lemma neg_mask_mono_le:
   "x \<le> y \<Longrightarrow> x AND NOT(mask n) \<le> y AND NOT(mask n)" for x :: "'a :: len word"
 proof (rule ccontr, simp add: linorder_not_le, cases "n < LENGTH('a)")
   case False
   then show "y AND NOT(mask n) < x AND NOT(mask n) \<Longrightarrow> False"
     by (simp add: mask_eq_decr_exp linorder_not_less power_overflow)
 next
   case True
   assume a: "x \<le> y" and b: "y AND NOT(mask n) < x AND NOT(mask n)"
   have word_bits: "n < LENGTH('a)" by fact
   have "y \<le> (y AND NOT(mask n)) + (y AND mask n)"
     by (simp add: word_plus_and_or_coroll2 add.commute)
   also have "\<dots> \<le> (y AND NOT(mask n)) + 2 ^ n"
     apply (rule word_plus_mono_right)
      apply (rule order_less_imp_le, rule and_mask_less_size)
      apply (simp add: word_size word_bits)
     apply (rule is_aligned_no_overflow'', simp add: is_aligned_neg_mask word_bits)
     apply (rule not_greatest_aligned, rule b; simp add: is_aligned_neg_mask)
     done
   also have "\<dots> \<le> x AND NOT(mask n)"
     using b
     apply (subst add.commute)
     apply (rule le_plus)
      apply (rule aligned_at_least_t2n_diff; simp add: is_aligned_neg_mask)
     apply (rule ccontr, simp add: linorder_not_le)
     apply (drule aligned_small_is_0[rotated]; simp add: is_aligned_neg_mask)
     done
   also have "\<dots> \<le> x" by (rule word_and_le2)
   also have "x \<le> y" by fact
   finally
   show "False" using b by simp
 qed
 
 lemma and_neg_mask_eq_iff_not_mask_le:
   "w AND NOT(mask n) = NOT(mask n) \<longleftrightarrow> NOT(mask n) \<le> w"
   for w :: \<open>'a::len word\<close>
   by (metis eq_iff neg_mask_mono_le word_and_le1 word_and_le2 word_bw_same(1))
 
-lemma neg_mask_le_high_bits [word_eqI_simps]:
+lemma neg_mask_le_high_bits:
   \<open>NOT (mask n) \<le> w \<longleftrightarrow> (\<forall>i \<in> {n ..< size w}. bit w i)\<close> (is \<open>?P \<longleftrightarrow> ?Q\<close>)
   for w :: \<open>'a::len word\<close>
 proof
   assume ?Q
   then have \<open>w AND NOT (mask n) = NOT (mask n)\<close>
     by (auto simp add: bit_simps word_size intro: bit_word_eqI)
   then show ?P
     by (simp add: and_neg_mask_eq_iff_not_mask_le)
 next
   assume ?P
   then have *: \<open>w AND NOT (mask n) = NOT (mask n)\<close>
     by (simp add: and_neg_mask_eq_iff_not_mask_le)
   show \<open>?Q\<close>
   proof (rule ccontr)
     assume \<open>\<not> (\<forall>i\<in>{n..<size w}. bit w i)\<close>
     then obtain m where m: \<open>\<not> bit w m\<close> \<open>n \<le> m\<close> \<open>m < LENGTH('a)\<close>
       by (auto simp add: word_size)
     from * have \<open>bit (w AND NOT (mask n)) m \<longleftrightarrow> bit (NOT (mask n :: 'a word)) m\<close>
       by auto
     with m show False by (auto simp add: bit_simps)
   qed
 qed
 
 lemma is_aligned_add_less_t2n:
   "\<lbrakk>is_aligned (p::'a::len word) n; d < 2^n; n \<le> m; p < 2^m\<rbrakk> \<Longrightarrow> p + d < 2^m"
   apply (case_tac "m < LENGTH('a)")
    apply (subst mask_eq_iff_w2p[symmetric])
     apply (simp add: word_size)
    apply (simp add: is_aligned_add_or word_ao_dist less_mask_eq)
    apply (subst less_mask_eq)
     apply (erule order_less_le_trans)
     apply (erule(1) two_power_increasing)
    apply simp
   apply (simp add: power_overflow)
   done
 
 lemma aligned_offset_non_zero:
   "\<lbrakk> is_aligned x n; y < 2 ^ n; x \<noteq> 0 \<rbrakk> \<Longrightarrow> x + y \<noteq> 0"
   apply (cases "y = 0")
    apply simp
   apply (subst word_neq_0_conv)
   apply (subst gt0_iff_gem1)
   apply (erule is_aligned_get_word_bits)
    apply (subst field_simps[symmetric], subst plus_le_left_cancel_nowrap)
      apply (rule is_aligned_no_wrap')
       apply simp
      apply (rule word_leq_le_minus_one)
       apply simp
      apply assumption
     apply (erule (1) is_aligned_no_wrap')
    apply (simp add: gt0_iff_gem1 [symmetric] word_neq_0_conv)
   apply simp
   done
 
 lemma is_aligned_over_length:
   "\<lbrakk> is_aligned p n; LENGTH('a) \<le> n \<rbrakk> \<Longrightarrow> (p::'a::len word) = 0"
   by (simp add: is_aligned_mask mask_over_length)
 
 lemma is_aligned_no_overflow_mask:
   "is_aligned x n \<Longrightarrow> x \<le> x + mask n"
   by (simp add: mask_eq_decr_exp) (erule is_aligned_no_overflow')
 
 lemma aligned_mask_step:
   "\<lbrakk> n' \<le> n; p' \<le> p + mask n; is_aligned p n; is_aligned p' n' \<rbrakk> \<Longrightarrow>
    (p'::'a::len word) + mask n' \<le> p + mask n"
   apply (cases "LENGTH('a) \<le> n")
    apply (frule (1) is_aligned_over_length)
    apply (drule mask_over_length)
    apply clarsimp
   apply (simp add: not_le)
   apply (simp add: word_le_nat_alt unat_plus_simple)
   apply (subst unat_plus_simple[THEN iffD1], erule is_aligned_no_overflow_mask)+
   apply (subst (asm) unat_plus_simple[THEN iffD1], erule is_aligned_no_overflow_mask)
   apply (clarsimp simp: dvd_def is_aligned_iff_dvd_nat)
   apply (rename_tac k k')
   apply (thin_tac "unat p = x" for p x)+
   apply (subst Suc_le_mono[symmetric])
   apply (simp only: Suc_2p_unat_mask)
   apply (drule le_imp_less_Suc, subst (asm) Suc_2p_unat_mask, assumption)
   apply (erule (1) power_2_mult_step_le)
   done
 
 lemma is_aligned_mask_offset_unat:
   fixes off :: "('a::len) word"
   and     x :: "'a word"
   assumes al: "is_aligned x sz"
   and   offv: "off \<le> mask sz"
   shows  "unat x + unat off < 2 ^ LENGTH('a)"
 proof cases
   assume szv: "sz < LENGTH('a)"
   from al obtain k where xv: "x = 2 ^ sz * (of_nat k)"
     and kl: "k < 2 ^ (LENGTH('a) - sz)"
     by (auto elim: is_alignedE)
 
   from offv szv have offv': "unat off < 2 ^ sz"
     by (simp add: mask_2pm1 unat_less_power)
 
   show ?thesis using szv
     using al is_aligned_no_wrap''' offv' by blast
 next
   assume "\<not> sz < LENGTH('a)"
   with al have "x = 0"
     by (meson is_aligned_get_word_bits) 
   thus ?thesis by simp
 qed
 
 lemma aligned_less_plus_1:
   "\<lbrakk> is_aligned x n; n > 0 \<rbrakk> \<Longrightarrow> x < x + 1"
   apply (rule plus_one_helper2)
    apply (rule order_refl)
   apply (clarsimp simp: field_simps)
   apply (drule arg_cong[where f="\<lambda>x. x - 1"])
   apply (clarsimp simp: is_aligned_mask)
-  apply (drule word_eqD[where x=0])
-  apply (simp add: even_mask_iff)
   done
 
 lemma aligned_add_offset_less:
   "\<lbrakk>is_aligned x n; is_aligned y n; x < y; z < 2 ^ n\<rbrakk> \<Longrightarrow> x + z < y"
   apply (cases "y = 0")
    apply simp
   apply (erule is_aligned_get_word_bits[where p=y], simp_all)
   apply (cases "z = 0", simp_all)
   apply (drule(2) aligned_at_least_t2n_diff[rotated -1])
   apply (drule plus_one_helper2)
    apply (rule less_is_non_zero_p1)
    apply (rule aligned_less_plus_1)
     apply (erule aligned_sub_aligned[OF _ _ order_refl],
            simp_all add: is_aligned_triv)[1]
    apply (cases n, simp_all)[1]
   apply (simp only: trans[OF diff_add_eq diff_diff_eq2[symmetric]])
   apply (drule word_less_add_right)
    apply (rule ccontr, simp add: linorder_not_le)
    apply (drule aligned_small_is_0, erule order_less_trans)
     apply (clarsimp simp: power_overflow)
    apply simp
   apply (erule order_le_less_trans[rotated],
          rule word_plus_mono_right)
    apply (erule word_le_minus_one_leq)
   apply (simp add: is_aligned_no_wrap' is_aligned_no_overflow field_simps)
   done
 
 lemma gap_between_aligned:
   "\<lbrakk>a < (b :: 'a ::len word); is_aligned a n; is_aligned b n; n < LENGTH('a) \<rbrakk>
   \<Longrightarrow> a + (2^n - 1) < b"
   by (simp add: aligned_add_offset_less)
 
 lemma is_aligned_add_step_le:
   "\<lbrakk> is_aligned (a::'a::len word) n; is_aligned b n; a < b; b \<le> a + mask n \<rbrakk> \<Longrightarrow> False"
   apply (simp flip: not_le)
   apply (erule notE)
   apply (cases "LENGTH('a) \<le> n")
    apply (drule (1) is_aligned_over_length)+
    apply (drule mask_over_length)
    apply clarsimp
   apply (clarsimp simp: word_le_nat_alt not_less not_le)
   apply (subst (asm) unat_plus_simple[THEN iffD1], erule is_aligned_no_overflow_mask)
   apply (subst (asm) unat_add_lem' [symmetric])
    apply (simp add: is_aligned_mask_offset_unat)
   apply (metis gap_between_aligned linorder_not_less mask_eq_decr_exp unat_arith_simps(2))
   done
 
 lemma aligned_add_mask_lessD:
   "\<lbrakk> x + mask n < y; is_aligned x n \<rbrakk> \<Longrightarrow> x < y" for y::"'a::len word"
   by (metis is_aligned_no_overflow' mask_2pm1 order_le_less_trans)
 
 lemma aligned_add_mask_less_eq:
   "\<lbrakk> is_aligned x n; is_aligned y n;  n < LENGTH('a) \<rbrakk> \<Longrightarrow> (x + mask n < y) = (x < y)"
   for y::"'a::len word"
   using aligned_add_mask_lessD is_aligned_add_step_le word_le_not_less by blast
 
 lemma is_aligned_diff:
   fixes m :: "'a::len word"
   assumes alm: "is_aligned m s1"
   and     aln: "is_aligned n s2"
   and    s2wb: "s2 < LENGTH('a)"
   and      nm: "m \<in> {n .. n + (2 ^ s2 - 1)}"
   and    s1s2: "s1 \<le> s2"
   and     s10: "0 < s1" (* Probably can be folded into the proof \<dots> *)
 shows  "\<exists>q. m - n = of_nat q * 2 ^ s1 \<and> q < 2 ^ (s2 - s1)"
 proof -
   have rl: "\<And>m s. \<lbrakk> m < 2 ^ (LENGTH('a) - s); s < LENGTH('a) \<rbrakk> \<Longrightarrow> unat ((2::'a word) ^ s * of_nat m) = 2 ^ s * m"
   proof -
     fix m :: nat and  s
     assume m: "m < 2 ^ (LENGTH('a) - s)" and s: "s < LENGTH('a)"
     then have "unat ((of_nat m) :: 'a word) = m"
       apply (subst unat_of_nat)
       apply (subst mod_less)
        apply (erule order_less_le_trans)
        apply (rule power_increasing)
         apply simp_all
       done
 
     then show "?thesis m s" using s m
       apply (subst iffD1 [OF unat_mult_lem])
       apply (simp add: nat_less_power_trans)+
       done
   qed
   have s1wb: "s1 < LENGTH('a)" using s2wb s1s2 by simp
   from alm obtain mq where mmq: "m = 2 ^ s1 * of_nat mq" and mq: "mq < 2 ^ (LENGTH('a) - s1)"
     by (auto elim: is_alignedE simp: field_simps)
   from aln obtain nq where nnq: "n = 2 ^ s2 * of_nat nq" and nq: "nq < 2 ^ (LENGTH('a) - s2)"
     by (auto elim: is_alignedE simp: field_simps)
   from s1s2 obtain sq where sq: "s2 = s1 + sq" by (auto simp: le_iff_add)
 
   note us1 = rl [OF mq s1wb]
   note us2 = rl [OF nq s2wb]
 
   from nm have "n \<le> m" by clarsimp
   then have "(2::'a word) ^ s2 * of_nat nq \<le> 2 ^ s1 * of_nat mq" using nnq mmq by simp
   then have "2 ^ s2 * nq \<le> 2 ^ s1 * mq" using s1wb s2wb
     by (simp add: word_le_nat_alt us1 us2)
   then have nqmq: "2 ^ sq * nq \<le> mq" using sq by (simp add: power_add)
 
   have "m - n = 2 ^ s1 * of_nat mq - 2 ^ s2 * of_nat nq" using mmq nnq by simp
   also have "\<dots> = 2 ^ s1 * of_nat mq - 2 ^ s1 * 2 ^ sq * of_nat nq" using sq by (simp add: power_add)
   also have "\<dots> = 2 ^ s1 * (of_nat mq - 2 ^ sq * of_nat nq)" by (simp add: field_simps)
   also have "\<dots> = 2 ^ s1 * of_nat (mq - 2 ^ sq * nq)" using s1wb s2wb us1 us2 nqmq
     by (simp add: of_nat_diff)
   finally have mn: "m - n = of_nat (mq - 2 ^ sq * nq) * 2 ^ s1" by simp
   moreover
   from nm have "m - n \<le> 2 ^ s2 - 1"
     by - (rule word_diff_ls', (simp add: field_simps)+)
   then have "(2::'a word) ^ s1 * of_nat (mq - 2 ^ sq * nq) < 2 ^ s2" using mn s2wb by (simp add: field_simps)
   then have "of_nat (mq - 2 ^ sq * nq) < (2::'a word) ^ (s2 - s1)"
   proof (rule word_power_less_diff)
     have mm: "mq - 2 ^ sq * nq < 2 ^ (LENGTH('a) - s1)" using mq by simp
     moreover from s10 have "LENGTH('a) - s1 < LENGTH('a)"
       by (rule diff_less, simp)
     ultimately show "of_nat (mq - 2 ^ sq * nq) < (2::'a word) ^ (LENGTH('a) - s1)"
       using take_bit_nat_less_self_iff [of \<open>LENGTH('a)\<close> \<open>mq - 2 ^ sq * nq\<close>]
       apply (auto simp add: word_less_nat_alt not_le not_less unsigned_of_nat)
       apply (metis take_bit_nat_eq_self_iff)
       done
   qed
   then have "mq - 2 ^ sq * nq < 2 ^ (s2 - s1)" using mq s2wb
     apply (simp add: word_less_nat_alt take_bit_eq_mod unsigned_of_nat)
     apply (subst (asm) mod_less)
     apply auto
      apply (rule order_le_less_trans)
       apply (rule diff_le_self)
      apply (erule order_less_le_trans)
     apply simp
     done
   ultimately show ?thesis
     by auto
 qed
 
 lemma is_aligned_addD1:
   assumes al1: "is_aligned (x + y) n"
   and     al2: "is_aligned (x::'a::len word) n"
   shows "is_aligned y n"
   using al2
 proof (rule is_aligned_get_word_bits)
   assume "x = 0" then show ?thesis using al1 by simp
 next
   assume nv: "n < LENGTH('a)"
   from al1 obtain q1
     where xy: "x + y = 2 ^ n * of_nat q1" and "q1 < 2 ^ (LENGTH('a) - n)"
     by (rule is_alignedE)
   moreover from al2 obtain q2
     where x: "x = 2 ^ n * of_nat q2" and "q2 < 2 ^ (LENGTH('a) - n)"
     by (rule is_alignedE)
   ultimately have "y = 2 ^ n * (of_nat q1 - of_nat q2)"
     by (simp add: field_simps)
   then show ?thesis using nv by (simp add: is_aligned_mult_triv1)
 qed
 
 lemmas is_aligned_addD2 =
        is_aligned_addD1[OF subst[OF add.commute,
                                  of "%x. is_aligned x n" for n]]
 
 lemma is_aligned_add:
   "\<lbrakk>is_aligned p n; is_aligned q n\<rbrakk> \<Longrightarrow> is_aligned (p + q) n"
   by (simp add: is_aligned_mask mask_add_aligned)
 
 lemma aligned_shift:
   "\<lbrakk>x < 2 ^ n; is_aligned (y :: 'a :: len word) n;n \<le> LENGTH('a)\<rbrakk>
-   \<Longrightarrow> drop_bit n (x + y) = drop_bit n y"
+   \<Longrightarrow> (x + y) >> n = y >> n"
   apply (subst word_plus_and_or_coroll; rule bit_word_eqI)
    apply (auto simp add: bit_simps is_aligned_nth)
    apply (metis less_2p_is_upper_bits_unset not_le)
   apply (metis le_add1 less_2p_is_upper_bits_unset test_bit_bin)
   done
 
 lemma aligned_shift':
   "\<lbrakk>x < 2 ^ n; is_aligned (y :: 'a :: len word) n;n \<le> LENGTH('a)\<rbrakk>
-   \<Longrightarrow> drop_bit n (y + x) = drop_bit n y"
+   \<Longrightarrow> (y + x) >> n = y >> n"
   apply (subst word_plus_and_or_coroll; rule bit_word_eqI)
    apply (auto simp add: bit_simps is_aligned_nth)
    apply (metis less_2p_is_upper_bits_unset not_le)
   apply (metis bit_imp_le_length le_add1 less_2p_is_upper_bits_unset)
   done
 
 lemma and_neg_mask_plus_mask_mono: "(p AND NOT (mask n)) + mask n \<ge> p"
   for p :: \<open>'a::len word\<close>
   apply (rule word_le_minus_cancel[where x = "p AND NOT (mask n)"])
    apply (clarsimp simp: subtract_mask)
    using word_and_le1[where a = "mask n" and y = p]
     apply (clarsimp simp: mask_eq_decr_exp word_le_less_eq)
   apply (rule is_aligned_no_overflow'[folded mask_2pm1])
   apply (clarsimp simp: is_aligned_neg_mask)
   done
 
 lemma word_neg_and_le:
   "ptr \<le> (ptr AND NOT (mask n)) + (2 ^ n - 1)"
   for ptr :: \<open>'a::len word\<close>
   by (simp add: and_neg_mask_plus_mask_mono mask_2pm1[symmetric])
 
 lemma is_aligned_sub_helper:
   "\<lbrakk> is_aligned (p - d) n; d < 2 ^ n \<rbrakk>
      \<Longrightarrow> (p AND mask n = d) \<and> (p AND (NOT (mask n)) = p - d)"
   by (drule(1) is_aligned_add_helper, simp)
 
 lemma is_aligned_after_mask:
   "\<lbrakk>is_aligned k m;m\<le> n\<rbrakk> \<Longrightarrow> is_aligned (k AND mask n) m"
   by (rule is_aligned_andI1)
 
 lemma and_mask_plus:
   "\<lbrakk>is_aligned ptr m; m \<le> n; a < 2 ^ m\<rbrakk>
    \<Longrightarrow> ptr + a AND mask n = (ptr AND mask n) + a"
   apply (rule mask_eqI[where n = m])
    apply (simp add:mask_twice min_def)
     apply (simp add:is_aligned_add_helper)
     apply (subst is_aligned_add_helper[THEN conjunct1])
       apply (erule is_aligned_after_mask)
      apply simp
     apply simp
    apply simp
   apply (subgoal_tac "(ptr + a AND mask n) AND NOT (mask m)
      = (ptr + a AND NOT (mask m) ) AND mask n")
    apply (simp add:is_aligned_add_helper)
    apply (subst is_aligned_add_helper[THEN conjunct2])
      apply (simp add:is_aligned_after_mask)
     apply simp
    apply simp
   apply (simp add:word_bw_comms word_bw_lcs)
   done
 
 lemma is_aligned_add_not_aligned:
   "\<lbrakk>is_aligned (p::'a::len word) n; \<not> is_aligned (q::'a::len word) n\<rbrakk> \<Longrightarrow> \<not> is_aligned (p + q) n"
   by (metis is_aligned_addD1)
 
 lemma neg_mask_add_aligned:
   "\<lbrakk> is_aligned p n; q < 2 ^ n \<rbrakk> \<Longrightarrow> (p + q) AND NOT (mask n) = p AND NOT (mask n)"
   by (metis is_aligned_add_helper is_aligned_neg_mask_eq)
 
 lemma word_add_power_off:
   fixes a :: "'a :: len word"
   assumes ak: "a < k"
   and kw: "k < 2 ^ (LENGTH('a) - m)"
   and mw: "m < LENGTH('a)"
   and off: "off < 2 ^ m"
 shows "(a * 2 ^ m) + off < k * 2 ^ m"
 proof (cases "m = 0")
   case True
   then show ?thesis using off ak by simp
 next
   case False
 
   from ak have ak1: "a + 1 \<le> k" by (rule inc_le)
   then have "(a + 1) * 2 ^ m \<noteq> 0"
     apply -
     apply (rule word_power_nonzero)
     apply (erule order_le_less_trans  [OF _ kw])
     apply (rule mw)
     apply (rule less_is_non_zero_p1 [OF ak])
     done
   then have "(a * 2 ^ m) + off < ((a + 1) * 2 ^ m)" using kw mw
     apply -
     apply (simp add: distrib_right)
     apply (rule word_plus_strict_mono_right [OF off])
     apply (rule is_aligned_no_overflow'')
     apply (rule is_aligned_mult_triv2)
     apply assumption
     done
   also have "\<dots> \<le> k * 2 ^ m" using ak1 mw kw False
     apply -
     apply (erule word_mult_le_mono1)
     apply (simp add: p2_gt_0)
     apply (simp add: word_less_nat_alt)
     apply (meson nat_mult_power_less_eq zero_less_numeral)
     done
   finally show ?thesis .
 qed
 
 lemma offset_not_aligned:
   "\<lbrakk> is_aligned (p::'a::len word) n; i > 0; i < 2 ^ n; n < LENGTH('a)\<rbrakk> \<Longrightarrow>
    \<not> is_aligned (p + of_nat i) n"
   apply (erule is_aligned_add_not_aligned)
   apply transfer
   apply (auto simp add: is_aligned_iff_udvd)
   apply (metis (no_types, lifting) le_less_trans less_not_refl2 less_or_eq_imp_le of_nat_eq_0_iff take_bit_eq_0_iff take_bit_nat_eq_self_iff take_bit_of_nat unat_lt2p unat_power_lower)
   done
 
 lemma le_or_mask:
   "w \<le> w' \<Longrightarrow> w OR mask x \<le> w' OR mask x"
   for w w' :: \<open>'a::len word\<close>
   by (metis neg_mask_add_mask add.commute le_word_or1 mask_2pm1 neg_mask_mono_le word_plus_mono_left)
 
 end
 
 end
diff --git a/thys/Word_Lib/Bit_Shifts_Infix_Syntax.thy b/thys/Word_Lib/Bit_Shifts_Infix_Syntax.thy
--- a/thys/Word_Lib/Bit_Shifts_Infix_Syntax.thy
+++ b/thys/Word_Lib/Bit_Shifts_Infix_Syntax.thy
@@ -1,29 +1,201 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (* Author: Jeremy Dawson, NICTA *)
 
-section \<open>Shift operations with traditional infix syntax\<close>
+section \<open>Shift operations with infix syntax\<close>
 
 theory Bit_Shifts_Infix_Syntax
-  imports "HOL-Library.Word"
+  imports "HOL-Library.Word" More_Word
 begin
 
 context semiring_bit_operations
 begin
 
-abbreviation shiftl :: \<open>'a \<Rightarrow> nat \<Rightarrow> 'a\<close>  (infixl "<<" 55)
-  where \<open>a << n \<equiv> push_bit n a\<close>
+definition shiftl :: \<open>'a \<Rightarrow> nat \<Rightarrow> 'a\<close>  (infixl "<<" 55)
+  where [code_unfold]: \<open>a << n = push_bit n a\<close>
 
-abbreviation shiftr :: \<open>'a \<Rightarrow> nat \<Rightarrow> 'a\<close>  (infixl ">>" 55)
-  where \<open>a >> n \<equiv> drop_bit n a\<close>
+lemma bit_shiftl_iff [bit_simps]:
+  \<open>bit (a << m) n \<longleftrightarrow> m \<le> n \<and> possible_bit TYPE('a) n \<and> bit a (n - m)\<close>
+  by (simp add: shiftl_def bit_simps)
+
+definition shiftr :: \<open>'a \<Rightarrow> nat \<Rightarrow> 'a\<close>  (infixl ">>" 55)
+  where [code_unfold]: \<open>a >> n = drop_bit n a\<close>
+
+lemma bit_shiftr_eq [bit_simps]:
+  \<open>bit (a >> n) = bit a \<circ> (+) n\<close>
+  by (simp add: shiftr_def bit_simps)
 
 end
 
-abbreviation sshiftr :: \<open>'a::len word \<Rightarrow> nat \<Rightarrow> 'a word\<close>  (infixl \<open>>>>\<close> 55)
-  where \<open>w >>> n \<equiv> signed_drop_bit n w\<close>
+definition sshiftr :: \<open>'a::len word \<Rightarrow> nat \<Rightarrow> 'a word\<close>  (infixl \<open>>>>\<close> 55)
+  where [code_unfold]: \<open>w >>> n = signed_drop_bit n w\<close>
+
+lemma bit_sshiftr_iff [bit_simps]:
+  \<open>bit (w >>> m) n \<longleftrightarrow> bit w (if LENGTH('a) - m \<le> n \<and> n < LENGTH('a) then LENGTH('a) - 1 else m + n)\<close>
+  for w :: \<open>'a::len word\<close>
+  by (simp add: sshiftr_def bit_simps)
+
+context
+  includes lifting_syntax
+begin
+
+lemma shiftl_word_transfer [transfer_rule]:
+  \<open>(pcr_word ===> (=) ===> pcr_word) (\<lambda>k n. push_bit n k) (<<)\<close>
+  apply (unfold shiftl_def)
+  apply transfer_prover
+  done
+
+lemma shiftr_word_transfer [transfer_rule]:
+  \<open>((pcr_word :: int \<Rightarrow> 'a::len word \<Rightarrow> _) ===> (=) ===> pcr_word)
+    (\<lambda>k n. drop_bit n (take_bit LENGTH('a) k))
+    (>>)\<close>
+proof -
+  have \<open>((pcr_word :: int \<Rightarrow> 'a::len word \<Rightarrow> _) ===> (=) ===> pcr_word)
+    (\<lambda>k n. (drop_bit n \<circ> take_bit LENGTH('a)) k)
+    (>>)\<close>
+    by (unfold shiftr_def) transfer_prover
+  then show ?thesis
+    by simp
+qed
+
+lemma sshiftr_transfer [transfer_rule]:
+  \<open>((pcr_word :: int \<Rightarrow> 'a::len word \<Rightarrow> _) ===> (=) ===> pcr_word)
+    (\<lambda>k n. drop_bit n (signed_take_bit (LENGTH('a) - Suc 0) k))
+    (>>>)\<close>
+proof -
+  have \<open>((pcr_word :: int \<Rightarrow> 'a::len word \<Rightarrow> _) ===> (=) ===> pcr_word)
+    (\<lambda>k n. (drop_bit n \<circ> signed_take_bit (LENGTH('a) - Suc 0)) k)
+    (>>>)\<close>
+    by (unfold sshiftr_def) transfer_prover
+  then show ?thesis
+    by simp
+qed
 
 end
+
+context semiring_bit_operations
+begin
+
+lemma shiftl_0 [simp]:
+  \<open>0 << n = 0\<close>
+  by (simp add: shiftl_def)
+
+lemma shiftl_of_0 [simp]:
+  \<open>a << 0 = a\<close>
+  by (simp add: shiftl_def)
+
+lemma shiftl_of_Suc [simp]:
+  \<open>a << Suc n = (a * 2) << n\<close>
+  by (simp add: shiftl_def)
+
+lemma shiftl_1 [simp]:
+  \<open>1 << n = 2 ^ n\<close>
+  by (simp add: shiftl_def)
+
+lemma shiftl_numeral_Suc [simp]:
+  \<open>numeral m << Suc n = push_bit (Suc n) (numeral m)\<close>
+  by (fact shiftl_def)
+
+lemma shiftl_numeral_numeral [simp]:
+  \<open>numeral m << numeral n = push_bit (numeral n) (numeral m)\<close>
+  by (fact shiftl_def)
+
+lemma shiftr_0 [simp]:
+  \<open>0 >> n = 0\<close>
+  by (simp add: shiftr_def)
+
+lemma shiftr_of_0 [simp]:
+  \<open>a >> 0 = a\<close>
+  by (simp add: shiftr_def)
+
+lemma shiftr_1 [simp]:
+  \<open>1 >> n = of_bool (n = 0)\<close>
+  by (simp add: shiftr_def)
+
+lemma shiftr_numeral_Suc [simp]:
+  \<open>numeral m >> Suc n = drop_bit (Suc n) (numeral m)\<close>
+  by (fact shiftr_def)
+
+lemma shiftr_numeral_numeral [simp]:
+  \<open>numeral m >> numeral n = drop_bit (numeral n) (numeral m)\<close>
+  by (fact shiftr_def)
+
+end
+
+context ring_bit_operations
+begin
+
+context
+  includes bit_operations_syntax
+begin
+
+lemma shiftl_minus_1_numeral [simp]:
+  \<open>- 1 << numeral n = NOT (mask (numeral n))\<close>
+  by (simp add: shiftl_def)
+
+end
+
+end
+
+lemma shiftl_Suc_0 [simp]:
+  \<open>Suc 0 << n = 2 ^ n\<close>
+  by (simp add: shiftl_def)
+
+lemma shiftr_Suc_0 [simp]:
+  \<open>Suc 0 >> n = of_bool (n = 0)\<close>
+  by (simp add: shiftr_def)
+
+lemma sshiftr_numeral_Suc [simp]:
+  \<open>numeral m >>> Suc n = signed_drop_bit (Suc n) (numeral m)\<close>
+  by (fact sshiftr_def)
+
+lemma sshiftr_numeral_numeral [simp]:
+  \<open>numeral m >>> numeral n = signed_drop_bit (numeral n) (numeral m)\<close>
+  by (fact sshiftr_def)
+
+context ring_bit_operations
+begin
+
+lemma shiftl_minus_numeral_Suc [simp]:
+  \<open>- numeral m << Suc n = push_bit (Suc n) (- numeral m)\<close>
+  by (fact shiftl_def)
+
+lemma shiftl_minus_numeral_numeral [simp]:
+  \<open>- numeral m << numeral n = push_bit (numeral n) (- numeral m)\<close>
+  by (fact shiftl_def)
+
+lemma shiftr_minus_numeral_Suc [simp]:
+  \<open>- numeral m >> Suc n = drop_bit (Suc n) (- numeral m)\<close>
+  by (fact shiftr_def)
+
+lemma shiftr_minus_numeral_numeral [simp]:
+  \<open>- numeral m >> numeral n = drop_bit (numeral n) (- numeral m)\<close>
+  by (fact shiftr_def)
+
+end
+
+lemma sshiftr_0 [simp]:
+  \<open>0 >>> n = 0\<close>
+  by (simp add: sshiftr_def)
+
+lemma sshiftr_of_0 [simp]:
+  \<open>w >>> 0 = w\<close>
+  by (simp add: sshiftr_def)
+
+lemma sshiftr_1 [simp]:
+  \<open>(1 :: 'a::len word) >>> n = of_bool (LENGTH('a) = 1 \<or> n = 0)\<close>
+  by (simp add: sshiftr_def)
+
+lemma sshiftr_minus_numeral_Suc [simp]:
+  \<open>- numeral m >>> Suc n = signed_drop_bit (Suc n) (- numeral m)\<close>
+  by (fact sshiftr_def)
+
+lemma sshiftr_minus_numeral_numeral [simp]:
+  \<open>- numeral m >>> numeral n = signed_drop_bit (numeral n) (- numeral m)\<close>
+  by (fact sshiftr_def)
+
+end
diff --git a/thys/Word_Lib/Bits_Int.thy b/thys/Word_Lib/Bits_Int.thy
--- a/thys/Word_Lib/Bits_Int.thy
+++ b/thys/Word_Lib/Bits_Int.thy
@@ -1,1573 +1,1573 @@
 (*
  * Copyright Brian Huffman, PSU; Jeremy Dawson and Gerwin Klein, NICTA
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section \<open>Bitwise Operations on integers\<close>
 
 theory Bits_Int
   imports
     "Word_Lib.Most_significant_bit"
     "Word_Lib.Least_significant_bit"
     "Word_Lib.Generic_set_bit"
     "Word_Lib.Bit_Comprehension"
 begin
 
 subsection \<open>Implicit bit representation of \<^typ>\<open>int\<close>\<close>
 
 lemma bin_last_def:
   "(odd :: int \<Rightarrow> bool) w \<longleftrightarrow> w mod 2 = 1"
   by (fact odd_iff_mod_2_eq_one)
 
 lemma bin_last_numeral_simps [simp]:
   "\<not> odd (0 :: int)"
   "odd (1 :: int)"
   "odd (- 1 :: int)"
   "odd (Numeral1 :: int)"
   "\<not> odd (numeral (Num.Bit0 w) :: int)"
   "odd (numeral (Num.Bit1 w) :: int)"
   "\<not> odd (- numeral (Num.Bit0 w) :: int)"
   "odd (- numeral (Num.Bit1 w) :: int)"
   by simp_all
 
 lemma bin_rest_numeral_simps [simp]:
   "(\<lambda>k::int. k div 2) 0 = 0"
   "(\<lambda>k::int. k div 2) 1 = 0"
   "(\<lambda>k::int. k div 2) (- 1) = - 1"
   "(\<lambda>k::int. k div 2) Numeral1 = 0"
   "(\<lambda>k::int. k div 2) (numeral (Num.Bit0 w)) = numeral w"
   "(\<lambda>k::int. k div 2) (numeral (Num.Bit1 w)) = numeral w"
   "(\<lambda>k::int. k div 2) (- numeral (Num.Bit0 w)) = - numeral w"
   "(\<lambda>k::int. k div 2) (- numeral (Num.Bit1 w)) = - numeral (w + Num.One)"
   by simp_all
 
 lemma bin_rl_eqI: "\<lbrakk>(\<lambda>k::int. k div 2) x = (\<lambda>k::int. k div 2) y; odd x = odd y\<rbrakk> \<Longrightarrow> x = y"
   by (auto elim: oddE)
 
 lemma [simp]:
   shows bin_rest_lt0: "(\<lambda>k::int. k div 2) i < 0 \<longleftrightarrow> i < 0"
   and  bin_rest_ge_0: "(\<lambda>k::int. k div 2) i \<ge> 0 \<longleftrightarrow> i \<ge> 0"
   by auto
 
 lemma bin_rest_gt_0 [simp]: "(\<lambda>k::int. k div 2) x > 0 \<longleftrightarrow> x > 1"
   by auto
 
 
 subsection \<open>Bit projection\<close>
 
 lemma bin_nth_eq_iff: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) x = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y \<longleftrightarrow> x = y"
   by (simp add: bit_eq_iff fun_eq_iff)
 
 lemma bin_eqI:
   "x = y" if "\<And>n. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n \<longleftrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n"
   using that by (rule bit_eqI)
 
 lemma bin_eq_iff: "x = y \<longleftrightarrow> (\<forall>n. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n)"
   by (metis bit_eq_iff)
 
 lemma bin_nth_zero [simp]: "\<not> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) 0 n"
   by simp
 
 lemma bin_nth_1 [simp]: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) 1 n \<longleftrightarrow> n = 0"
   by (cases n) (simp_all add: bit_Suc)
 
 lemma bin_nth_minus1 [simp]: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (- 1) n"
   by simp
 
 lemma bin_nth_numeral: "(\<lambda>k::int. k div 2) x = y \<Longrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x (numeral n) = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y (pred_numeral n)"
   by (simp add: numeral_eq_Suc bit_Suc)
 
 lemmas bin_nth_numeral_simps [simp] =
   bin_nth_numeral [OF bin_rest_numeral_simps(8)]
 
 lemmas bin_nth_simps =
   bit_0 bit_Suc bin_nth_zero bin_nth_minus1
   bin_nth_numeral_simps
 
 lemma nth_2p_bin: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (2 ^ n) m = (m = n)" \<comment> \<open>for use when simplifying with \<open>bin_nth_Bit\<close>\<close>
   by (auto simp add: bit_exp_iff)
 
 lemma nth_rest_power_bin: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (((\<lambda>k::int. k div 2) ^^ k) w) n = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w (n + k)"
   apply (induct k arbitrary: n)
    apply clarsimp
   apply clarsimp
   apply (simp only: bit_Suc [symmetric] add_Suc)
   done
 
 lemma bin_nth_numeral_unfold:
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral (num.Bit0 x)) n \<longleftrightarrow> n > 0 \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral x) (n - 1)"
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral (num.Bit1 x)) n \<longleftrightarrow> (n > 0 \<longrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral x) (n - 1))"
   by (cases n; simp)+
 
 
 subsection \<open>Truncating\<close>
 
 definition bin_sign :: "int \<Rightarrow> int"
   where "bin_sign k = (if k \<ge> 0 then 0 else - 1)"
 
 lemma bin_sign_simps [simp]:
   "bin_sign 0 = 0"
   "bin_sign 1 = 0"
   "bin_sign (- 1) = - 1"
   "bin_sign (numeral k) = 0"
   "bin_sign (- numeral k) = -1"
   by (simp_all add: bin_sign_def)
 
 lemma bin_sign_rest [simp]: "bin_sign ((\<lambda>k::int. k div 2) w) = bin_sign w"
   by (simp add: bin_sign_def)
 
 lemma bintrunc_mod2p: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w = w mod 2 ^ n"
   by (fact take_bit_eq_mod)
 
 lemma sbintrunc_mod2p: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w = (w + 2 ^ n) mod 2 ^ Suc n - 2 ^ n"
   by (simp add: bintrunc_mod2p signed_take_bit_eq_take_bit_shift)
 
 lemma sbintrunc_eq_take_bit:
   \<open>(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n k = take_bit (Suc n) (k + 2 ^ n) - 2 ^ n\<close>
   by (fact signed_take_bit_eq_take_bit_shift)
 
 lemma sign_bintr: "bin_sign ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = 0"
   by (simp add: bin_sign_def)
 
 lemma bintrunc_n_0: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n 0 = 0"
   by (fact take_bit_of_0)
 
 lemma sbintrunc_n_0: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n 0 = 0"
   by (fact signed_take_bit_of_0)
 
 lemma sbintrunc_n_minus1: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- 1) = -1"
   by (fact signed_take_bit_of_minus_1)
 
 lemma bintrunc_Suc_numeral:
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) 1 = 1"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- 1) = 1 + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- 1)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (numeral (Num.Bit0 w)) = 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (numeral (Num.Bit1 w)) = 1 + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- numeral (Num.Bit0 w)) = 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- numeral (Num.Bit1 w)) = 1 + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- numeral (w + Num.One))"
-  by (simp_all add: take_bit_Suc)
+  by (simp_all add: take_bit_Suc del: take_bit_minus_one_eq_mask)
 
 lemma sbintrunc_0_numeral [simp]:
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) 0 1 = -1"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) 0 (numeral (Num.Bit0 w)) = 0"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) 0 (numeral (Num.Bit1 w)) = -1"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) 0 (- numeral (Num.Bit0 w)) = 0"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) 0 (- numeral (Num.Bit1 w)) = -1"
   by simp_all
 
 lemma sbintrunc_Suc_numeral:
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) 1 = 1"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (numeral (Num.Bit0 w)) = 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (numeral (Num.Bit1 w)) = 1 + 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- numeral (Num.Bit0 w)) = 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- numeral (Num.Bit1 w)) = 1 + 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- numeral (w + Num.One))"
   by (simp_all add: signed_take_bit_Suc)
 
 lemma bin_sign_lem: "(bin_sign ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin) = -1) = bit bin n"
   by (simp add: bin_sign_def)
 
 lemma nth_bintr: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w) n \<longleftrightarrow> n < m \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w n"
   by (fact bit_take_bit_iff)
 
 lemma nth_sbintr: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w) n = (if n < m then (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w n else (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w m)"
   by (simp add: bit_signed_take_bit_iff min_def)
 
 lemma bin_nth_Bit0:
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral (Num.Bit0 w)) n \<longleftrightarrow>
     (\<exists>m. n = Suc m \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral w) m)"
   using bit_double_iff [of \<open>numeral w :: int\<close> n]
   by (auto intro: exI [of _ \<open>n - 1\<close>])
 
 lemma bin_nth_Bit1:
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral (Num.Bit1 w)) n \<longleftrightarrow>
     n = 0 \<or> (\<exists>m. n = Suc m \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (numeral w) m)"
   using even_bit_succ_iff [of \<open>2 * numeral w :: int\<close> n]
     bit_double_iff [of \<open>numeral w :: int\<close> n]
   by auto
 
 lemma bintrunc_bintrunc_l: "n \<le> m \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
-  by (simp add: min.absorb2)
+  by simp
 
 lemma sbintrunc_sbintrunc_l: "n \<le> m \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
-  by (simp add: min.absorb2)
+  by simp
 
 lemma bintrunc_bintrunc_ge: "n \<le> m \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (rule bin_eqI) (auto simp: nth_bintr)
 
 lemma bintrunc_bintrunc_min [simp]: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (min m n) w"
   by (rule take_bit_take_bit)
 
 lemma sbintrunc_sbintrunc_min [simp]: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (min m n) w"
   by (rule signed_take_bit_signed_take_bit)
 
 lemmas sbintrunc_Suc_Pls =
   signed_take_bit_Suc [where a="0::int", simplified bin_last_numeral_simps bin_rest_numeral_simps]
 
 lemmas sbintrunc_Suc_Min =
   signed_take_bit_Suc [where a="-1::int", simplified bin_last_numeral_simps bin_rest_numeral_simps]
 
 lemmas sbintrunc_Sucs = sbintrunc_Suc_Pls sbintrunc_Suc_Min
   sbintrunc_Suc_numeral
 
 lemmas sbintrunc_Pls =
   signed_take_bit_0 [where a="0::int", simplified bin_last_numeral_simps bin_rest_numeral_simps]
 
 lemmas sbintrunc_Min =
   signed_take_bit_0 [where a="-1::int", simplified bin_last_numeral_simps bin_rest_numeral_simps]
 
 lemmas sbintrunc_0_simps =
   sbintrunc_Pls sbintrunc_Min
 
 lemmas sbintrunc_simps = sbintrunc_0_simps sbintrunc_Sucs
 
 lemma bintrunc_minus: "0 < n \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc (n - 1)) w = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by auto
 
 lemma sbintrunc_minus: "0 < n \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc (n - 1)) w = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by auto
 
 lemmas sbintrunc_minus_simps =
   sbintrunc_Sucs [THEN [2] sbintrunc_minus [symmetric, THEN trans]]
 
 lemma sbintrunc_BIT_I:
   \<open>0 < n \<Longrightarrow>
   (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) 0 = y \<Longrightarrow>
   (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n 0 = 2 * y\<close>
   by simp
 
 lemma sbintrunc_Suc_Is:
   \<open>(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- 1) = y \<Longrightarrow>
   (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) (- 1) = 1 + 2 * y\<close>
   by auto
 
 lemma sbintrunc_Suc_lem: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) x = y \<Longrightarrow> m = Suc n \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m x = y"
   by (rule ssubst)
 
 lemmas sbintrunc_Suc_Ialts =
   sbintrunc_Suc_Is [THEN sbintrunc_Suc_lem]
 
 lemma sbintrunc_bintrunc_lt: "m > n \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w) = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (rule bin_eqI) (auto simp: nth_sbintr nth_bintr)
 
 lemma bintrunc_sbintrunc_le: "m \<le> Suc n \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w"
   by (rule take_bit_signed_take_bit)
 
 lemmas bintrunc_sbintrunc [simp] = order_refl [THEN bintrunc_sbintrunc_le]
 lemmas sbintrunc_bintrunc [simp] = lessI [THEN sbintrunc_bintrunc_lt]
 lemmas bintrunc_bintrunc [simp] = order_refl [THEN bintrunc_bintrunc_l]
 lemmas sbintrunc_sbintrunc [simp] = order_refl [THEN sbintrunc_sbintrunc_l]
 
 lemma bintrunc_sbintrunc' [simp]: "0 < n \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) w) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (cases n) simp_all
 
 lemma sbintrunc_bintrunc' [simp]: "0 < n \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w) = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) w"
   by (cases n) simp_all
 
 lemma bin_sbin_eq_iff: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) x = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) y \<longleftrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y"
   apply (rule iffI)
    apply (rule box_equals [OF _ sbintrunc_bintrunc sbintrunc_bintrunc])
    apply simp
   apply (rule box_equals [OF _ bintrunc_sbintrunc bintrunc_sbintrunc])
   apply simp
   done
 
 lemma bin_sbin_eq_iff':
   "0 < n \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y \<longleftrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) x = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) y"
   by (cases n) (simp_all add: bin_sbin_eq_iff)
 
 lemmas bintrunc_sbintruncS0 [simp] = bintrunc_sbintrunc' [unfolded One_nat_def]
 lemmas sbintrunc_bintruncS0 [simp] = sbintrunc_bintrunc' [unfolded One_nat_def]
 
 lemmas bintrunc_bintrunc_l' = le_add1 [THEN bintrunc_bintrunc_l]
 lemmas sbintrunc_sbintrunc_l' = le_add1 [THEN sbintrunc_sbintrunc_l]
 
 (* although bintrunc_minus_simps, if added to default simpset,
   tends to get applied where it's not wanted in developing the theories,
   we get a version for when the word length is given literally *)
 
 lemmas nat_non0_gr =
   trans [OF iszero_def [THEN Not_eq_iff [THEN iffD2]] refl]
 
 lemma bintrunc_numeral:
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) x = of_bool (odd x) + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (x div 2)"
   by (simp add: numeral_eq_Suc take_bit_Suc mod_2_eq_odd)
 
 lemma sbintrunc_numeral:
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) x = of_bool (odd x) + 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (x div 2)"
   by (simp add: numeral_eq_Suc signed_take_bit_Suc mod2_eq_if)
 
 lemma bintrunc_numeral_simps [simp]:
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (numeral (Num.Bit0 w)) =
     2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (numeral (Num.Bit1 w)) =
     1 + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (- numeral (Num.Bit0 w)) =
     2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (- numeral w)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (- numeral (Num.Bit1 w)) =
     1 + 2 * (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (- numeral (w + Num.One))"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) 1 = 1"
   by (simp_all add: bintrunc_numeral)
 
 lemma sbintrunc_numeral_simps [simp]:
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (numeral (Num.Bit0 w)) =
     2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (numeral (Num.Bit1 w)) =
     1 + 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (- numeral (Num.Bit0 w)) =
     2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (- numeral w)"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) (- numeral (Num.Bit1 w)) =
     1 + 2 * (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (pred_numeral k) (- numeral (w + Num.One))"
   "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (numeral k) 1 = 1"
   by (simp_all add: sbintrunc_numeral)
 
 lemma no_bintr_alt1: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n = (\<lambda>w. w mod 2 ^ n :: int)"
   by (rule ext) (rule bintrunc_mod2p)
 
 lemma range_bintrunc: "range ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n) = {i. 0 \<le> i \<and> i < 2 ^ n}"
   by (auto simp add: take_bit_eq_mod image_iff) (metis mod_pos_pos_trivial)
 
 lemma no_sbintr_alt2: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n = (\<lambda>w. (w + 2 ^ n) mod 2 ^ Suc n - 2 ^ n :: int)"
   by (rule ext) (simp add : sbintrunc_mod2p)
 
 lemma range_sbintrunc: "range ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n) = {i. - (2 ^ n) \<le> i \<and> i < 2 ^ n}"
 proof -
   have \<open>surj (\<lambda>k::int. k + 2 ^ n)\<close>
     by (rule surjI [of _ \<open>(\<lambda>k. k - 2 ^ n)\<close>]) simp
   moreover have \<open>(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n = ((\<lambda>k. k - 2 ^ n) \<circ> take_bit (Suc n) \<circ> (\<lambda>k. k + 2 ^ n))\<close>
     by (simp add: sbintrunc_eq_take_bit fun_eq_iff)
   ultimately show ?thesis
     apply (simp only: fun.set_map range_bintrunc)
     apply (auto simp add: image_iff)
     apply presburger
     done
 qed
 
 lemma sbintrunc_inc:
   \<open>k + 2 ^ Suc n \<le> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n k\<close> if \<open>k < - (2 ^ n)\<close>
   using that by (fact signed_take_bit_int_greater_eq)
 
 lemma sbintrunc_dec:
   \<open>(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n k \<le> k - 2 ^ (Suc n)\<close> if \<open>k \<ge> 2 ^ n\<close>
   using that by (fact signed_take_bit_int_less_eq)
 
 lemma bintr_ge0: "0 \<le> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (simp add: bintrunc_mod2p)
 
 lemma bintr_lt2p: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w < 2 ^ n"
   by (simp add: bintrunc_mod2p)
 
 lemma bintr_Min: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- 1) = 2 ^ n - 1"
-  by (simp add: stable_imp_take_bit_eq)
+  by (simp add: stable_imp_take_bit_eq mask_eq_exp_minus_1)
 
 lemma sbintr_ge: "- (2 ^ n) \<le> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (fact signed_take_bit_int_greater_eq_minus_exp)
 
 lemma sbintr_lt: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w < 2 ^ n"
   by (fact signed_take_bit_int_less_exp)
 
 lemma sign_Pls_ge_0: "bin_sign bin = 0 \<longleftrightarrow> bin \<ge> 0"
   for bin :: int
   by (simp add: bin_sign_def)
 
 lemma sign_Min_lt_0: "bin_sign bin = -1 \<longleftrightarrow> bin < 0"
   for bin :: int
   by (simp add: bin_sign_def)
 
 lemma bin_rest_trunc: "(\<lambda>k::int. k div 2) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - 1) ((\<lambda>k::int. k div 2) bin)"
   by (simp add: take_bit_rec [of n bin])
 
 lemma bin_rest_power_trunc:
   "((\<lambda>k::int. k div 2) ^^ k) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (n - k) (((\<lambda>k::int. k div 2) ^^ k) bin)"
   by (induct k) (auto simp: bin_rest_trunc)
 
 lemma bin_rest_trunc_i: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((\<lambda>k::int. k div 2) bin) = (\<lambda>k::int. k div 2) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) bin)"
   by (auto simp add: take_bit_Suc)
 
 lemma bin_rest_strunc: "(\<lambda>k::int. k div 2) ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (Suc n) bin) = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((\<lambda>k::int. k div 2) bin)"
   by (simp add: signed_take_bit_Suc)
 
 lemma bintrunc_rest [simp]: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((\<lambda>k::int. k div 2) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin)) = (\<lambda>k::int. k div 2) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin)"
   by (induct n arbitrary: bin) (simp_all add: take_bit_Suc)
 
 lemma sbintrunc_rest [simp]: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((\<lambda>k::int. k div 2) ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin)) = (\<lambda>k::int. k div 2) ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n bin)"
   by (induct n arbitrary: bin) (simp_all add: signed_take_bit_Suc mod2_eq_if)
 
 lemma bintrunc_rest': "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n \<circ> (\<lambda>k::int. k div 2) \<circ> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n = (\<lambda>k::int. k div 2) \<circ> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n"
   by (rule ext) auto
 
 lemma sbintrunc_rest': "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n \<circ> (\<lambda>k::int. k div 2) \<circ> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n = (\<lambda>k::int. k div 2) \<circ> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n"
   by (rule ext) auto
 
 lemma rco_lem: "f \<circ> g \<circ> f = g \<circ> f \<Longrightarrow> f \<circ> (g \<circ> f) ^^ n = g ^^ n \<circ> f"
   apply (rule ext)
   apply (induct_tac n)
    apply (simp_all (no_asm))
   apply (drule fun_cong)
   apply (unfold o_def)
   apply (erule trans)
   apply simp
   done
 
 lemmas rco_bintr = bintrunc_rest'
   [THEN rco_lem [THEN fun_cong], unfolded o_def]
 lemmas rco_sbintr = sbintrunc_rest'
   [THEN rco_lem [THEN fun_cong], unfolded o_def]
 
 
 subsection \<open>Splitting and concatenation\<close>
 
 definition bin_split :: \<open>nat \<Rightarrow> int \<Rightarrow> int \<times> int\<close>
   where [simp]: \<open>bin_split n k = (drop_bit n k, take_bit n k)\<close>
 
 lemma [code]:
   "bin_split (Suc n) w = (let (w1, w2) = bin_split n (w div 2) in (w1, of_bool (odd w) + 2 * w2))"
   "bin_split 0 w = (w, 0)"
   by (simp_all add: drop_bit_Suc take_bit_Suc mod_2_eq_odd)
 
 lemma bin_cat_eq_push_bit_add_take_bit:
   \<open>concat_bit n l k = push_bit n k + take_bit n l\<close>
   by (simp add: concat_bit_eq)
 
 lemma bin_sign_cat: "bin_sign ((\<lambda>k n l. concat_bit n l k) x n y) = bin_sign x"
 proof -
   have \<open>0 \<le> x\<close> if \<open>0 \<le> x * 2 ^ n + y mod 2 ^ n\<close>
   proof -
     have \<open>y mod 2 ^ n < 2 ^ n\<close>
       using pos_mod_bound [of \<open>2 ^ n\<close> y] by simp
     then have \<open>\<not> y mod 2 ^ n \<ge> 2 ^ n\<close>
       by (simp add: less_le)
     with that have \<open>x \<noteq> - 1\<close>
       by auto
     have *: \<open>- 1 \<le> (- (y mod 2 ^ n)) div 2 ^ n\<close>
       by (simp add: zdiv_zminus1_eq_if)
     from that have \<open>- (y mod 2 ^ n) \<le> x * 2 ^ n\<close>
       by simp
     then have \<open>(- (y mod 2 ^ n)) div 2 ^ n \<le> (x * 2 ^ n) div 2 ^ n\<close>
       using zdiv_mono1 zero_less_numeral zero_less_power by blast
     with * have \<open>- 1 \<le> x * 2 ^ n div 2 ^ n\<close> by simp
     with \<open>x \<noteq> - 1\<close> show ?thesis
       by simp
   qed
   then show ?thesis
     by (simp add: bin_sign_def not_le not_less bin_cat_eq_push_bit_add_take_bit push_bit_eq_mult take_bit_eq_mod)
 qed
 
 lemma bin_cat_assoc: "(\<lambda>k n l. concat_bit n l k) ((\<lambda>k n l. concat_bit n l k) x m y) n z = (\<lambda>k n l. concat_bit n l k) x (m + n) ((\<lambda>k n l. concat_bit n l k) y n z)"
   by (fact concat_bit_assoc)
 
 lemma bin_cat_assoc_sym: "(\<lambda>k n l. concat_bit n l k) x m ((\<lambda>k n l. concat_bit n l k) y n z) = (\<lambda>k n l. concat_bit n l k) ((\<lambda>k n l. concat_bit n l k) x (m - n) y) (min m n) z"
   by (fact concat_bit_assoc_sym)
 
 definition bin_rcat :: \<open>nat \<Rightarrow> int list \<Rightarrow> int\<close>
   where \<open>bin_rcat n = horner_sum (take_bit n) (2 ^ n) \<circ> rev\<close>
 
 lemma bin_rcat_eq_foldl:
   \<open>bin_rcat n = foldl (\<lambda>u v. (\<lambda>k n l. concat_bit n l k) u n v) 0\<close>
 proof
   fix ks :: \<open>int list\<close>
   show \<open>bin_rcat n ks = foldl (\<lambda>u v. (\<lambda>k n l. concat_bit n l k) u n v) 0 ks\<close>
     by (induction ks rule: rev_induct)
       (simp_all add: bin_rcat_def concat_bit_eq push_bit_eq_mult)
 qed
 
 fun bin_rsplit_aux :: "nat \<Rightarrow> nat \<Rightarrow> int \<Rightarrow> int list \<Rightarrow> int list"
   where "bin_rsplit_aux n m c bs =
     (if m = 0 \<or> n = 0 then bs
      else
       let (a, b) = bin_split n c
       in bin_rsplit_aux n (m - n) a (b # bs))"
 
 definition bin_rsplit :: "nat \<Rightarrow> nat \<times> int \<Rightarrow> int list"
   where "bin_rsplit n w = bin_rsplit_aux n (fst w) (snd w) []"
 
 fun bin_rsplitl_aux :: "nat \<Rightarrow> nat \<Rightarrow> int \<Rightarrow> int list \<Rightarrow> int list"
   where "bin_rsplitl_aux n m c bs =
     (if m = 0 \<or> n = 0 then bs
      else
       let (a, b) = bin_split (min m n) c
       in bin_rsplitl_aux n (m - n) a (b # bs))"
 
 definition bin_rsplitl :: "nat \<Rightarrow> nat \<times> int \<Rightarrow> int list"
   where "bin_rsplitl n w = bin_rsplitl_aux n (fst w) (snd w) []"
 
 declare bin_rsplit_aux.simps [simp del]
 declare bin_rsplitl_aux.simps [simp del]
 
 lemma bin_nth_cat:
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) ((\<lambda>k n l. concat_bit n l k) x k y) n =
     (if n < k then (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n else (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x (n - k))"
   by (simp add: bit_concat_bit_iff)
 
 lemma bin_nth_drop_bit_iff:
   \<open>(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (drop_bit n c) k \<longleftrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) c (n + k)\<close>
   by (simp add: bit_drop_bit_eq)
 
 lemma bin_nth_take_bit_iff:
   \<open>(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (take_bit n c) k \<longleftrightarrow> k < n \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) c k\<close>
   by (fact bit_take_bit_iff)
 
 lemma bin_nth_split:
   "bin_split n c = (a, b) \<Longrightarrow>
     (\<forall>k. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) a k = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) c (n + k)) \<and>
     (\<forall>k. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) b k = (k < n \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) c k))"
   by (auto simp add: bin_nth_drop_bit_iff bin_nth_take_bit_iff)
 
 lemma bin_cat_zero [simp]: "(\<lambda>k n l. concat_bit n l k) 0 n w = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (simp add: bin_cat_eq_push_bit_add_take_bit)
 
 lemma bintr_cat1: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (k + n) ((\<lambda>k n l. concat_bit n l k) a n b) = (\<lambda>k n l. concat_bit n l k) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) k a) n b"
   by (metis bin_cat_assoc bin_cat_zero)
 
 lemma bintr_cat: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m ((\<lambda>k n l. concat_bit n l k) a n b) =
     (\<lambda>k n l. concat_bit n l k) ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (m - n) a) n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (min m n) b)"
   by (rule bin_eqI) (auto simp: bin_nth_cat nth_bintr)
 
 lemma bintr_cat_same [simp]: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((\<lambda>k n l. concat_bit n l k) a n b) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n b"
   by (auto simp add : bintr_cat)
 
 lemma cat_bintr [simp]: "(\<lambda>k n l. concat_bit n l k) a n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n b) = (\<lambda>k n l. concat_bit n l k) a n b"
   by (simp add: bin_cat_eq_push_bit_add_take_bit)
 
 lemma split_bintrunc: "bin_split n c = (a, b) \<Longrightarrow> b = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n c"
   by simp
 
 lemma bin_cat_split: "bin_split n w = (u, v) \<Longrightarrow> w = (\<lambda>k n l. concat_bit n l k) u n v"
   by (auto simp add: bin_cat_eq_push_bit_add_take_bit bits_ident)
 
 lemma drop_bit_bin_cat_eq:
   \<open>drop_bit n ((\<lambda>k n l. concat_bit n l k) v n w) = v\<close>
   by (rule bit_eqI) (simp add: bit_drop_bit_eq bit_concat_bit_iff)
 
 lemma take_bit_bin_cat_eq:
   \<open>take_bit n ((\<lambda>k n l. concat_bit n l k) v n w) = take_bit n w\<close>
   by (rule bit_eqI) (simp add: bit_concat_bit_iff)
 
 lemma bin_split_cat: "bin_split n ((\<lambda>k n l. concat_bit n l k) v n w) = (v, (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w)"
   by (simp add: drop_bit_bin_cat_eq take_bit_bin_cat_eq)
 
 lemma bin_split_zero [simp]: "bin_split n 0 = (0, 0)"
   by simp
 
 lemma bin_split_minus1 [simp]:
   "bin_split n (- 1) = (- 1, (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (- 1))"
   by simp
 
 lemma bin_split_trunc:
   "bin_split (min m n) c = (a, b) \<Longrightarrow>
     bin_split n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m c) = ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (m - n) a, b)"
   apply (induct n arbitrary: m b c, clarsimp)
   apply (simp add: bin_rest_trunc Let_def split: prod.split_asm)
   apply (case_tac m)
    apply (auto simp: Let_def drop_bit_Suc take_bit_Suc mod_2_eq_odd split: prod.split_asm)
   done
 
 lemma bin_split_trunc1:
   "bin_split n c = (a, b) \<Longrightarrow>
     bin_split n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m c) = ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (m - n) a, (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m b)"
   apply (induct n arbitrary: m b c, clarsimp)
   apply (simp add: bin_rest_trunc Let_def split: prod.split_asm)
   apply (case_tac m)
    apply (auto simp: Let_def drop_bit_Suc take_bit_Suc mod_2_eq_odd split: prod.split_asm)
   done
 
 lemma bin_cat_num: "(\<lambda>k n l. concat_bit n l k) a n b = a * 2 ^ n + (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n b"
   by (simp add: bin_cat_eq_push_bit_add_take_bit push_bit_eq_mult)
 
 lemma bin_split_num: "bin_split n b = (b div 2 ^ n, b mod 2 ^ n)"
   by (simp add: drop_bit_eq_div take_bit_eq_mod)
 
 lemmas bin_rsplit_aux_simps = bin_rsplit_aux.simps bin_rsplitl_aux.simps
 lemmas rsplit_aux_simps = bin_rsplit_aux_simps
 
 lemmas th_if_simp1 = if_split [where P = "(=) l", THEN iffD1, THEN conjunct1, THEN mp] for l
 lemmas th_if_simp2 = if_split [where P = "(=) l", THEN iffD1, THEN conjunct2, THEN mp] for l
 
 lemmas rsplit_aux_simp1s = rsplit_aux_simps [THEN th_if_simp1]
 
 lemmas rsplit_aux_simp2ls = rsplit_aux_simps [THEN th_if_simp2]
 \<comment> \<open>these safe to \<open>[simp add]\<close> as require calculating \<open>m - n\<close>\<close>
 lemmas bin_rsplit_aux_simp2s [simp] = rsplit_aux_simp2ls [unfolded Let_def]
 lemmas rbscl = bin_rsplit_aux_simp2s (2)
 
 lemmas rsplit_aux_0_simps [simp] =
   rsplit_aux_simp1s [OF disjI1] rsplit_aux_simp1s [OF disjI2]
 
 lemma bin_rsplit_aux_append: "bin_rsplit_aux n m c (bs @ cs) = bin_rsplit_aux n m c bs @ cs"
   apply (induct n m c bs rule: bin_rsplit_aux.induct)
   apply (subst bin_rsplit_aux.simps)
   apply (subst bin_rsplit_aux.simps)
   apply (clarsimp split: prod.split)
   done
 
 lemma bin_rsplitl_aux_append: "bin_rsplitl_aux n m c (bs @ cs) = bin_rsplitl_aux n m c bs @ cs"
   apply (induct n m c bs rule: bin_rsplitl_aux.induct)
   apply (subst bin_rsplitl_aux.simps)
   apply (subst bin_rsplitl_aux.simps)
   apply (clarsimp split: prod.split)
   done
 
 lemmas rsplit_aux_apps [where bs = "[]"] =
   bin_rsplit_aux_append bin_rsplitl_aux_append
 
 lemmas rsplit_def_auxs = bin_rsplit_def bin_rsplitl_def
 
 lemmas rsplit_aux_alts = rsplit_aux_apps
   [unfolded append_Nil rsplit_def_auxs [symmetric]]
 
 lemma bin_split_minus: "0 < n \<Longrightarrow> bin_split (Suc (n - 1)) w = bin_split n w"
   by auto
 
 lemma bin_split_pred_simp [simp]:
   "(0::nat) < numeral bin \<Longrightarrow>
     bin_split (numeral bin) w =
       (let (w1, w2) = bin_split (numeral bin - 1) ((\<lambda>k::int. k div 2) w)
        in (w1, of_bool (odd w) + 2 * w2))"
   by (simp add: take_bit_rec drop_bit_rec mod_2_eq_odd)
 
 lemma bin_rsplit_aux_simp_alt:
   "bin_rsplit_aux n m c bs =
     (if m = 0 \<or> n = 0 then bs
      else let (a, b) = bin_split n c in bin_rsplit n (m - n, a) @ b # bs)"
   apply (simp add: bin_rsplit_aux.simps [of n m c bs])
   apply (subst rsplit_aux_alts)
   apply (simp add: bin_rsplit_def)
   done
 
 lemmas bin_rsplit_simp_alt =
   trans [OF bin_rsplit_def bin_rsplit_aux_simp_alt]
 
 lemmas bthrs = bin_rsplit_simp_alt [THEN [2] trans]
 
 lemma bin_rsplit_size_sign' [rule_format]:
   "n > 0 \<Longrightarrow> rev sw = bin_rsplit n (nw, w) \<Longrightarrow> \<forall>v\<in>set sw. (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n v = v"
   apply (induct sw arbitrary: nw w)
    apply clarsimp
   apply clarsimp
   apply (drule bthrs)
   apply (simp (no_asm_use) add: Let_def split: prod.split_asm if_split_asm)
   apply clarify
   apply simp
   done
 
 lemmas bin_rsplit_size_sign = bin_rsplit_size_sign' [OF asm_rl
   rev_rev_ident [THEN trans] set_rev [THEN equalityD2 [THEN subsetD]]]
 
 lemma bin_nth_rsplit [rule_format] :
   "n > 0 \<Longrightarrow> m < n \<Longrightarrow>
     \<forall>w k nw.
       rev sw = bin_rsplit n (nw, w) \<longrightarrow>
       k < size sw \<longrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (sw ! k) m = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w (k * n + m)"
   apply (induct sw)
    apply clarsimp
   apply clarsimp
   apply (drule bthrs)
   apply (simp (no_asm_use) add: Let_def split: prod.split_asm if_split_asm)
   apply (erule allE, erule impE, erule exI)
   apply (case_tac k)
    apply clarsimp
    prefer 2
    apply clarsimp
    apply (erule allE)
    apply (erule (1) impE)
    apply (simp add: bit_drop_bit_eq ac_simps)
   apply (simp add: bit_take_bit_iff ac_simps)
   done
 
 lemma bin_rsplit_all: "0 < nw \<Longrightarrow> nw \<le> n \<Longrightarrow> bin_rsplit n (nw, w) = [(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w]"
   by (auto simp: bin_rsplit_def rsplit_aux_simp2ls split: prod.split dest!: split_bintrunc)
 
 lemma bin_rsplit_l [rule_format]:
   "\<forall>bin. bin_rsplitl n (m, bin) = bin_rsplit n (m, (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m bin)"
   apply (rule_tac a = "m" in wf_less_than [THEN wf_induct])
   apply (simp (no_asm) add: bin_rsplitl_def bin_rsplit_def)
   apply (rule allI)
   apply (subst bin_rsplitl_aux.simps)
   apply (subst bin_rsplit_aux.simps)
   apply (clarsimp simp: Let_def split: prod.split)
   apply (simp add: ac_simps)
   apply (subst rsplit_aux_alts(1))
   apply (subst rsplit_aux_alts(2))
   apply clarsimp
   unfolding bin_rsplit_def bin_rsplitl_def
   apply (simp add: drop_bit_take_bit)
   apply (case_tac \<open>x < n\<close>)
   apply (simp_all add: not_less min_def)
   done
 
 lemma bin_rsplit_rcat [rule_format]:
   "n > 0 \<longrightarrow> bin_rsplit n (n * size ws, bin_rcat n ws) = map ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n) ws"
   apply (unfold bin_rsplit_def bin_rcat_eq_foldl)
   apply (rule_tac xs = ws in rev_induct)
    apply clarsimp
   apply clarsimp
   apply (subst rsplit_aux_alts)
   apply (simp add: drop_bit_bin_cat_eq take_bit_bin_cat_eq)
   done
 
 lemma bin_rsplit_aux_len_le [rule_format] :
   "\<forall>ws m. n \<noteq> 0 \<longrightarrow> ws = bin_rsplit_aux n nw w bs \<longrightarrow>
     length ws \<le> m \<longleftrightarrow> nw + length bs * n \<le> m * n"
 proof -
   have *: R
     if d: "i \<le> j \<or> m < j'"
     and R1: "i * k \<le> j * k \<Longrightarrow> R"
     and R2: "Suc m * k' \<le> j' * k' \<Longrightarrow> R"
     for i j j' k k' m :: nat and R
     using d
     apply safe
     apply (rule R1, erule mult_le_mono1)
     apply (rule R2, erule Suc_le_eq [THEN iffD2 [THEN mult_le_mono1]])
     done
   have **: "0 < sc \<Longrightarrow> sc - n + (n + lb * n) \<le> m * n \<longleftrightarrow> sc + lb * n \<le> m * n"
     for sc m n lb :: nat
     apply safe
      apply arith
     apply (case_tac "sc \<ge> n")
      apply arith
     apply (insert linorder_le_less_linear [of m lb])
     apply (erule_tac k=n and k'=n in *)
      apply arith
     apply simp
     done
   show ?thesis
     apply (induct n nw w bs rule: bin_rsplit_aux.induct)
     apply (subst bin_rsplit_aux.simps)
     apply (simp add: ** Let_def split: prod.split)
     done
 qed
 
 lemma bin_rsplit_len_le: "n \<noteq> 0 \<longrightarrow> ws = bin_rsplit n (nw, w) \<longrightarrow> length ws \<le> m \<longleftrightarrow> nw \<le> m * n"
   by (auto simp: bin_rsplit_def bin_rsplit_aux_len_le)
 
 lemma bin_rsplit_aux_len:
   "n \<noteq> 0 \<Longrightarrow> length (bin_rsplit_aux n nw w cs) = (nw + n - 1) div n + length cs"
   apply (induct n nw w cs rule: bin_rsplit_aux.induct)
   apply (subst bin_rsplit_aux.simps)
   apply (clarsimp simp: Let_def split: prod.split)
   apply (erule thin_rl)
   apply (case_tac m)
    apply simp
   apply (case_tac "m \<le> n")
    apply (auto simp add: div_add_self2)
   done
 
 lemma bin_rsplit_len: "n \<noteq> 0 \<Longrightarrow> length (bin_rsplit n (nw, w)) = (nw + n - 1) div n"
   by (auto simp: bin_rsplit_def bin_rsplit_aux_len)
 
 lemma bin_rsplit_aux_len_indep:
   "n \<noteq> 0 \<Longrightarrow> length bs = length cs \<Longrightarrow>
     length (bin_rsplit_aux n nw v bs) =
     length (bin_rsplit_aux n nw w cs)"
 proof (induct n nw w cs arbitrary: v bs rule: bin_rsplit_aux.induct)
   case (1 n m w cs v bs)
   show ?case
   proof (cases "m = 0")
     case True
     with \<open>length bs = length cs\<close> show ?thesis by simp
   next
     case False
     from "1.hyps" [of \<open>bin_split n w\<close> \<open>drop_bit n w\<close> \<open>take_bit n w\<close>] \<open>m \<noteq> 0\<close> \<open>n \<noteq> 0\<close>
     have hyp: "\<And>v bs. length bs = Suc (length cs) \<Longrightarrow>
       length (bin_rsplit_aux n (m - n) v bs) =
       length (bin_rsplit_aux n (m - n) (drop_bit n w) (take_bit n w # cs))"
       using bin_rsplit_aux_len by fastforce
     from \<open>length bs = length cs\<close> \<open>n \<noteq> 0\<close> show ?thesis
       by (auto simp add: bin_rsplit_aux_simp_alt Let_def bin_rsplit_len split: prod.split)
   qed
 qed
 
 lemma bin_rsplit_len_indep:
   "n \<noteq> 0 \<Longrightarrow> length (bin_rsplit n (nw, v)) = length (bin_rsplit n (nw, w))"
   apply (unfold bin_rsplit_def)
   apply (simp (no_asm))
   apply (erule bin_rsplit_aux_len_indep)
   apply (rule refl)
   done
 
 
 subsection \<open>Logical operations\<close>
 
 abbreviation (input) bin_sc :: \<open>nat \<Rightarrow> bool \<Rightarrow> int \<Rightarrow> int\<close>
   where \<open>bin_sc n b i \<equiv> set_bit i n b\<close>
 
 lemma bin_sc_0 [simp]:
   "bin_sc 0 b w = of_bool b + 2 * (\<lambda>k::int. k div 2) w"
   by (simp add: set_bit_int_def)
 
 lemma bin_sc_Suc [simp]:
   "bin_sc (Suc n) b w = of_bool (odd w) + 2 * bin_sc n b (w div 2)"
   by (simp add: set_bit_int_def set_bit_Suc unset_bit_Suc bin_last_def)
 
 lemma bin_nth_sc [bit_simps]: "bit (bin_sc n b w) n \<longleftrightarrow> b"
   by (simp add: bit_simps)
 
 lemma bin_sc_sc_same [simp]: "bin_sc n c (bin_sc n b w) = bin_sc n c w"
   by (induction n arbitrary: w) (simp_all add: bit_Suc)
 
 lemma bin_sc_sc_diff: "m \<noteq> n \<Longrightarrow> bin_sc m c (bin_sc n b w) = bin_sc n b (bin_sc m c w)"
   apply (induct n arbitrary: w m)
    apply (case_tac [!] m)
      apply auto
   done
 
 lemma bin_nth_sc_gen: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (bin_sc n b w) m = (if m = n then b else (bit :: int \<Rightarrow> nat \<Rightarrow> bool) w m)"
   apply (induct n arbitrary: w m)
    apply (case_tac m; simp add: bit_Suc)
   apply (case_tac m; simp add: bit_Suc)
   done
 
 lemma bin_sc_eq:
   \<open>bin_sc n False = unset_bit n\<close>
   \<open>bin_sc n True = Bit_Operations.set_bit n\<close>
    apply (simp_all add: fun_eq_iff bit_eq_iff)
   apply (simp_all add: bit_simps bin_nth_sc_gen)
   done
 
 lemma bin_sc_nth [simp]: "bin_sc n ((bit :: int \<Rightarrow> nat \<Rightarrow> bool) w n) w = w"
   by (rule bit_eqI) (simp add: bin_nth_sc_gen)
 
 lemma bin_sign_sc [simp]: "bin_sign (bin_sc n b w) = bin_sign w"
 proof (induction n arbitrary: w)
   case 0
   then show ?case
     by (auto simp add: bin_sign_def) (use bin_rest_ge_0 in fastforce)
 next
   case (Suc n)
   from Suc [of \<open>w div 2\<close>]
   show ?case by (auto simp add: bin_sign_def split: if_splits)
 qed
 
 lemma bin_sc_bintr [simp]:
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m (bin_sc n x ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m w)) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) m (bin_sc n x w)"
   apply (rule bit_eqI)
   apply (cases x)
    apply (auto simp add: bit_simps bin_sc_eq)
   done
 
 lemma bin_clr_le: "bin_sc n False w \<le> w"
   by (simp add: set_bit_int_def unset_bit_less_eq)
 
 lemma bin_set_ge: "bin_sc n True w \<ge> w"
   by (simp add: set_bit_int_def set_bit_greater_eq)
 
 lemma bintr_bin_clr_le: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (bin_sc m False w) \<le> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (simp add: set_bit_int_def take_bit_unset_bit_eq unset_bit_less_eq)
 
 lemma bintr_bin_set_ge: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (bin_sc m True w) \<ge> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n w"
   by (simp add: set_bit_int_def take_bit_set_bit_eq set_bit_greater_eq)
 
 lemma bin_sc_FP [simp]: "bin_sc n False 0 = 0"
   by (induct n) auto
 
 lemma bin_sc_TM [simp]: "bin_sc n True (- 1) = - 1"
   by (induct n) auto
 
 lemmas bin_sc_simps = bin_sc_0 bin_sc_Suc bin_sc_TM bin_sc_FP
 
 lemma bin_sc_minus: "0 < n \<Longrightarrow> bin_sc (Suc (n - 1)) b w = bin_sc n b w"
   by auto
 
 lemmas bin_sc_Suc_minus =
   trans [OF bin_sc_minus [symmetric] bin_sc_Suc]
 
 lemma bin_sc_numeral [simp]:
   "bin_sc (numeral k) b w =
     of_bool (odd w) + 2 * bin_sc (pred_numeral k) b (w div 2)"
   by (simp add: numeral_eq_Suc)
 
 lemmas bin_sc_minus_simps =
   bin_sc_simps (2,3,4) [THEN [2] trans, OF bin_sc_minus [THEN sym]]
 
 lemma int_set_bit_0 [simp]: fixes x :: int shows
   "set_bit x 0 b = of_bool b + 2 * (x div 2)"
   by (fact bin_sc_0)
 
 lemma int_set_bit_Suc: fixes x :: int shows
   "set_bit x (Suc n) b = of_bool (odd x) + 2 * set_bit (x div 2) n b"
   by (fact bin_sc_Suc)
 
 lemma bin_last_set_bit:
   "odd (set_bit x n b :: int) = (if n > 0 then odd x else b)"
   by (cases n) (simp_all add: int_set_bit_Suc)
 
 lemma bin_rest_set_bit:
   "(set_bit x n b :: int) div 2 = (if n > 0 then set_bit (x div 2) (n - 1) b else x div 2)"
   by (cases n) (simp_all add: int_set_bit_Suc)
 
 lemma int_set_bit_numeral: fixes x :: int shows
   "set_bit x (numeral w) b = of_bool (odd x) + 2 * set_bit (x div 2) (pred_numeral w) b"
   by (fact bin_sc_numeral)
 
 lemmas int_set_bit_numerals [simp] =
   int_set_bit_numeral[where x="numeral w'"]
   int_set_bit_numeral[where x="- numeral w'"]
   int_set_bit_numeral[where x="Numeral1"]
   int_set_bit_numeral[where x="1"]
   int_set_bit_numeral[where x="0"]
   int_set_bit_Suc[where x="numeral w'"]
   int_set_bit_Suc[where x="- numeral w'"]
   int_set_bit_Suc[where x="Numeral1"]
   int_set_bit_Suc[where x="1"]
   int_set_bit_Suc[where x="0"]
   for w'
 
 lemma msb_set_bit [simp]:
   "msb (set_bit (x :: int) n b) \<longleftrightarrow> msb x"
   by (simp add: msb_int_def set_bit_int_def)
 
 lemma word_set_bit_def:
   \<open>set_bit a n x = word_of_int (bin_sc n x (uint a))\<close>
   apply (rule bit_word_eqI)
   apply (cases x)
    apply (simp_all add: bit_simps bin_sc_eq)
   done
 
 lemma set_bit_word_of_int:
   "set_bit (word_of_int x) n b = word_of_int (bin_sc n b x)"
   unfolding word_set_bit_def
   by (rule word_eqI) (simp add: word_size bin_nth_sc_gen nth_bintr bit_simps)
 
 lemma word_set_numeral [simp]:
   "set_bit (numeral bin::'a::len word) n b =
     word_of_int (bin_sc n b (numeral bin))"
   unfolding word_numeral_alt by (rule set_bit_word_of_int)
 
 lemma word_set_neg_numeral [simp]:
   "set_bit (- numeral bin::'a::len word) n b =
     word_of_int (bin_sc n b (- numeral bin))"
   unfolding word_neg_numeral_alt by (rule set_bit_word_of_int)
 
 lemma word_set_bit_0 [simp]: "set_bit 0 n b = word_of_int (bin_sc n b 0)"
   unfolding word_0_wi by (rule set_bit_word_of_int)
 
 lemma word_set_bit_1 [simp]: "set_bit 1 n b = word_of_int (bin_sc n b 1)"
   unfolding word_1_wi by (rule set_bit_word_of_int)
 
 lemma shiftl_int_def:
   "push_bit n x = x * 2 ^ n" for x :: int
   by (fact push_bit_eq_mult)
 
 lemma shiftr_int_def:
   "drop_bit n x = x div 2 ^ n" for x :: int
   by (fact drop_bit_eq_div)
 
 
 subsubsection \<open>Basic simplification rules\<close>
 
 context
   includes bit_operations_syntax
 begin
 
 lemmas int_not_def = not_int_def
 
 lemma int_not_simps:
   "NOT (0::int) = -1"
   "NOT (1::int) = -2"
   "NOT (- 1::int) = 0"
   "NOT (numeral w::int) = - numeral (w + Num.One)"
   "NOT (- numeral (Num.Bit0 w)::int) = numeral (Num.BitM w)"
   "NOT (- numeral (Num.Bit1 w)::int) = numeral (Num.Bit0 w)"
   by (simp_all add: not_int_def)
 
 lemma int_not_not: "NOT (NOT x) = x"
   for x :: int
   by (fact bit.double_compl)
 
 lemma int_and_0 [simp]: "0 AND x = 0"
   for x :: int
   by (fact bit.conj_zero_left)
 
 lemma int_and_m1 [simp]: "-1 AND x = x"
   for x :: int
   by (fact and.left_neutral)
 
 lemma int_or_zero [simp]: "0 OR x = x"
   for x :: int
   by (fact or.left_neutral)
 
 lemma int_or_minus1 [simp]: "-1 OR x = -1"
   for x :: int
   by (fact bit.disj_one_left)
 
 lemma int_xor_zero [simp]: "0 XOR x = x"
   for x :: int
   by (fact xor.left_neutral)
 
 
 subsubsection \<open>Binary destructors\<close>
 
 lemma bin_rest_NOT [simp]: "(\<lambda>k::int. k div 2) (NOT x) = NOT ((\<lambda>k::int. k div 2) x)"
   by (fact not_int_div_2)
 
 lemma bin_last_NOT [simp]: "(odd :: int \<Rightarrow> bool) (NOT x) \<longleftrightarrow> \<not> (odd :: int \<Rightarrow> bool) x"
   by simp
 
 lemma bin_rest_AND [simp]: "(\<lambda>k::int. k div 2) (x AND y) = (\<lambda>k::int. k div 2) x AND (\<lambda>k::int. k div 2) y"
   by (subst and_int_rec) auto
 
 lemma bin_last_AND [simp]: "(odd :: int \<Rightarrow> bool) (x AND y) \<longleftrightarrow> (odd :: int \<Rightarrow> bool) x \<and> (odd :: int \<Rightarrow> bool) y"
   by (subst and_int_rec) auto
 
 lemma bin_rest_OR [simp]: "(\<lambda>k::int. k div 2) (x OR y) = (\<lambda>k::int. k div 2) x OR (\<lambda>k::int. k div 2) y"
   by (subst or_int_rec) auto
 
 lemma bin_last_OR [simp]: "(odd :: int \<Rightarrow> bool) (x OR y) \<longleftrightarrow> (odd :: int \<Rightarrow> bool) x \<or> (odd :: int \<Rightarrow> bool) y"
   by (subst or_int_rec) auto
 
 lemma bin_rest_XOR [simp]: "(\<lambda>k::int. k div 2) (x XOR y) = (\<lambda>k::int. k div 2) x XOR (\<lambda>k::int. k div 2) y"
   by (subst xor_int_rec) auto
 
 lemma bin_last_XOR [simp]: "(odd :: int \<Rightarrow> bool) (x XOR y) \<longleftrightarrow> ((odd :: int \<Rightarrow> bool) x \<or> (odd :: int \<Rightarrow> bool) y) \<and> \<not> ((odd :: int \<Rightarrow> bool) x \<and> (odd :: int \<Rightarrow> bool) y)"
   by (subst xor_int_rec) auto
 
 lemma bin_nth_ops:
   "\<And>x y. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (x AND y) n \<longleftrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n"
   "\<And>x y. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (x OR y) n \<longleftrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n \<or> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n"
   "\<And>x y. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (x XOR y) n \<longleftrightarrow> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n \<noteq> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) y n"
   "\<And>x. (bit :: int \<Rightarrow> nat \<Rightarrow> bool) (NOT x) n \<longleftrightarrow> \<not> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n"
   by (simp_all add: bit_and_iff bit_or_iff bit_xor_iff bit_not_iff)
 
 
 subsubsection \<open>Derived properties\<close>
 
 lemma int_xor_minus1 [simp]: "-1 XOR x = NOT x"
   for x :: int
   by (fact bit.xor_one_left)
 
 lemma int_xor_extra_simps [simp]:
   "w XOR 0 = w"
   "w XOR -1 = NOT w"
   for w :: int
   by simp_all
 
 lemma int_or_extra_simps [simp]:
   "w OR 0 = w"
   "w OR -1 = -1"
   for w :: int
   by simp_all
 
 lemma int_and_extra_simps [simp]:
   "w AND 0 = 0"
   "w AND -1 = w"
   for w :: int
   by simp_all
 
 text \<open>Commutativity of the above.\<close>
 lemma bin_ops_comm:
   fixes x y :: int
   shows int_and_comm: "x AND y = y AND x"
     and int_or_comm:  "x OR y = y OR x"
     and int_xor_comm: "x XOR y = y XOR x"
   by (simp_all add: ac_simps)
 
 lemma bin_ops_same [simp]:
   "x AND x = x"
   "x OR x = x"
   "x XOR x = 0"
   for x :: int
   by simp_all
 
 lemmas bin_log_esimps =
   int_and_extra_simps  int_or_extra_simps  int_xor_extra_simps
   int_and_0 int_and_m1 int_or_zero int_or_minus1 int_xor_zero int_xor_minus1
 
 
 subsubsection \<open>Basic properties of logical (bit-wise) operations\<close>
 
 lemma bbw_ao_absorb: "x AND (y OR x) = x \<and> x OR (y AND x) = x"
   for x y :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma bbw_ao_absorbs_other:
   "x AND (x OR y) = x \<and> (y AND x) OR x = x"
   "(y OR x) AND x = x \<and> x OR (x AND y) = x"
   "(x OR y) AND x = x \<and> (x AND y) OR x = x"
   for x y :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemmas bbw_ao_absorbs [simp] = bbw_ao_absorb bbw_ao_absorbs_other
 
 lemma int_xor_not: "(NOT x) XOR y = NOT (x XOR y) \<and> x XOR (NOT y) = NOT (x XOR y)"
   for x y :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma int_and_assoc: "(x AND y) AND z = x AND (y AND z)"
   for x y z :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma int_or_assoc: "(x OR y) OR z = x OR (y OR z)"
   for x y z :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma int_xor_assoc: "(x XOR y) XOR z = x XOR (y XOR z)"
   for x y z :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemmas bbw_assocs = int_and_assoc int_or_assoc int_xor_assoc
 
 (* BH: Why are these declared as simp rules??? *)
 lemma bbw_lcs [simp]:
   "y AND (x AND z) = x AND (y AND z)"
   "y OR (x OR z) = x OR (y OR z)"
   "y XOR (x XOR z) = x XOR (y XOR z)"
   for x y :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma bbw_not_dist:
   "NOT (x OR y) = (NOT x) AND (NOT y)"
   "NOT (x AND y) = (NOT x) OR (NOT y)"
   for x y :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma bbw_oa_dist: "(x AND y) OR z = (x OR z) AND (y OR z)"
   for x y z :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 lemma bbw_ao_dist: "(x OR y) AND z = (x AND z) OR (y AND z)"
   for x y z :: int
   by (auto simp add: bin_eq_iff bin_nth_ops)
 
 
 subsubsection \<open>Simplification with numerals\<close>
 
 text \<open>Cases for \<open>0\<close> and \<open>-1\<close> are already covered by other simp rules.\<close>
 
 lemma bin_rest_neg_numeral_BitM [simp]:
   "(\<lambda>k::int. k div 2) (- numeral (Num.BitM w)) = - numeral w"
   by simp
 
 lemma bin_last_neg_numeral_BitM [simp]:
   "(odd :: int \<Rightarrow> bool) (- numeral (Num.BitM w))"
   by simp
 
 
 subsubsection \<open>Interactions with arithmetic\<close>
 
 lemma le_int_or: "bin_sign y = 0 \<Longrightarrow> x \<le> x OR y"
   for x y :: int
   by (simp add: bin_sign_def or_greater_eq split: if_splits)
 
 lemmas int_and_le =
   xtrans(3) [OF bbw_ao_absorbs (2) [THEN conjunct2, symmetric] le_int_or]
 
 text \<open>Interaction between bit-wise and arithmetic: good example of \<open>bin_induction\<close>.\<close>
 lemma bin_add_not: "x + NOT x = (-1::int)"
   by (simp add: not_int_def)
 
 lemma AND_mod: "x AND (2 ^ n - 1) = x mod 2 ^ n"
   for x :: int
   by (simp flip: take_bit_eq_mod add: take_bit_eq_mask mask_eq_exp_minus_1)
 
 
 subsubsection \<open>Truncating results of bit-wise operations\<close>
 
 lemma bin_trunc_ao:
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x AND (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (x AND y)"
   "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x OR (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (x OR y)"
   by simp_all
 
 lemma bin_trunc_xor: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x XOR (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (x XOR y)"
   by simp
 
 lemma bin_trunc_not: "(take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (NOT ((take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x)) = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n (NOT x)"
   by (fact take_bit_not_take_bit)
 
 text \<open>Want theorems of the form of \<open>bin_trunc_xor\<close>.\<close>
 lemma bintr_bintr_i: "x = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y \<Longrightarrow> (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x = (take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n y"
   by auto
 
 lemmas bin_trunc_and = bin_trunc_ao(1) [THEN bintr_bintr_i]
 lemmas bin_trunc_or = bin_trunc_ao(2) [THEN bintr_bintr_i]
 
 
 subsubsection \<open>More lemmas\<close>
 
 lemma not_int_cmp_0 [simp]:
   fixes i :: int shows
   "0 < NOT i \<longleftrightarrow> i < -1"
   "0 \<le> NOT i \<longleftrightarrow> i < 0"
   "NOT i < 0 \<longleftrightarrow> i \<ge> 0"
   "NOT i \<le> 0 \<longleftrightarrow> i \<ge> -1"
 by(simp_all add: int_not_def) arith+
 
 lemma bbw_ao_dist2: "(x :: int) AND (y OR z) = x AND y OR x AND z"
   by (fact bit.conj_disj_distrib)
 
 lemmas int_and_ac = bbw_lcs(1) int_and_comm int_and_assoc
 
 lemma int_nand_same [simp]: fixes x :: int shows "x AND NOT x = 0"
   by simp
 
 lemma int_nand_same_middle: fixes x :: int shows "x AND y AND NOT x = 0"
   by (simp add: bit_eq_iff bit_and_iff bit_not_iff)
 
 lemma and_xor_dist: fixes x :: int shows
   "x AND (y XOR z) = (x AND y) XOR (x AND z)"
   by (fact bit.conj_xor_distrib)
 
 lemma int_and_lt0 [simp]:
   \<open>x AND y < 0 \<longleftrightarrow> x < 0 \<and> y < 0\<close> for x y :: int
   by (fact and_negative_int_iff)
 
 lemma int_and_ge0 [simp]:
   \<open>x AND y \<ge> 0 \<longleftrightarrow> x \<ge> 0 \<or> y \<ge> 0\<close> for x y :: int
   by (fact and_nonnegative_int_iff)
 
 lemma int_and_1: fixes x :: int shows "x AND 1 = x mod 2"
   by (fact and_one_eq)
 
 lemma int_1_and: fixes x :: int shows "1 AND x = x mod 2"
   by (fact one_and_eq)
 
 lemma int_or_lt0 [simp]:
   \<open>x OR y < 0 \<longleftrightarrow> x < 0 \<or> y < 0\<close> for x y :: int
   by (fact or_negative_int_iff)
 
 lemma int_or_ge0 [simp]:
   \<open>x OR y \<ge> 0 \<longleftrightarrow> x \<ge> 0 \<and> y \<ge> 0\<close> for x y :: int
   by (fact or_nonnegative_int_iff)
 
 lemma int_xor_lt0 [simp]:
   \<open>x XOR y < 0 \<longleftrightarrow> (x < 0) \<noteq> (y < 0)\<close> for x y :: int
   by (fact xor_negative_int_iff)
 
 lemma int_xor_ge0 [simp]:
   \<open>x XOR y \<ge> 0 \<longleftrightarrow> (x \<ge> 0 \<longleftrightarrow> y \<ge> 0)\<close> for x y :: int
   by (fact xor_nonnegative_int_iff)
 
 lemma even_conv_AND:
   \<open>even i \<longleftrightarrow> i AND 1 = 0\<close> for i :: int
   by (simp add: and_one_eq mod2_eq_if)
 
 lemma bin_last_conv_AND:
   "(odd :: int \<Rightarrow> bool) i \<longleftrightarrow> i AND 1 \<noteq> 0"
   by (simp add: and_one_eq mod2_eq_if)
 
 lemma bitval_bin_last:
   "of_bool ((odd :: int \<Rightarrow> bool) i) = i AND 1"
   by (simp add: and_one_eq mod2_eq_if)
 
 lemma bin_sign_and:
   "bin_sign (i AND j) = - (bin_sign i * bin_sign j)"
 by(simp add: bin_sign_def)
 
 lemma int_not_neg_numeral: "NOT (- numeral n) = (Num.sub n num.One :: int)"
 by(simp add: int_not_def)
 
 lemma int_neg_numeral_pOne_conv_not: "- numeral (n + num.One) = (NOT (numeral n) :: int)"
 by(simp add: int_not_def)
 
 
 subsection \<open>Setting and clearing bits\<close>
 
 lemma int_shiftl_BIT: fixes x :: int
   shows int_shiftl0: "push_bit 0 x = x"
   and int_shiftl_Suc: "push_bit (Suc n) x = 2 * push_bit n x"
   by (auto simp add: shiftl_int_def)
 
 lemma int_0_shiftl: "push_bit n 0 = (0 :: int)"
   by (fact push_bit_of_0)
 
 lemma bin_last_shiftl: "odd (push_bit n x) \<longleftrightarrow> n = 0 \<and> (odd :: int \<Rightarrow> bool) x"
   by simp
 
 lemma bin_rest_shiftl: "(\<lambda>k::int. k div 2) (push_bit n x) = (if n > 0 then push_bit (n - 1) x else (\<lambda>k::int. k div 2) x)"
   by (cases n) (simp_all add: push_bit_eq_mult)
 
 lemma bin_nth_shiftl: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (push_bit n x) m \<longleftrightarrow> n \<le> m \<and> (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x (m - n)"
   by (fact bit_push_bit_iff_int)
 
 lemma bin_last_shiftr: "odd (drop_bit n x) \<longleftrightarrow> bit x n" for x :: int
   by (simp add: bit_iff_odd_drop_bit)
 
 lemma bin_rest_shiftr: "(\<lambda>k::int. k div 2) (drop_bit n x) = drop_bit (Suc n) x"
   by (simp add: drop_bit_Suc drop_bit_half)
 
 lemma bin_nth_shiftr: "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) (drop_bit n x) m = (bit :: int \<Rightarrow> nat \<Rightarrow> bool) x (n + m)"
   by (simp add: bit_simps)
 
 lemma bin_nth_conv_AND:
   fixes x :: int shows
   "(bit :: int \<Rightarrow> nat \<Rightarrow> bool) x n \<longleftrightarrow> x AND (push_bit n 1) \<noteq> 0"
   by (fact bit_iff_and_push_bit_not_eq_0)
 
 lemma int_shiftl_numeral [simp]:
   "push_bit (numeral w') (numeral w :: int) = push_bit (pred_numeral w') (numeral (num.Bit0 w))"
   "push_bit (numeral w') (- numeral w :: int) = push_bit (pred_numeral w') (- numeral (num.Bit0 w))"
 by(simp_all add: numeral_eq_Suc shiftl_int_def)
   (metis add_One mult_inc semiring_norm(11) semiring_norm(13) semiring_norm(2) semiring_norm(6) semiring_norm(87))+
 
 lemma int_shiftl_One_numeral [simp]:
   "push_bit (numeral w) (1::int) = push_bit (pred_numeral w) 2"
   using int_shiftl_numeral [of Num.One w]
-  by (simp add: numeral_eq_Suc) 
+  by (simp only: numeral_eq_Suc push_bit_Suc) simp
 
 lemma shiftl_ge_0: fixes i :: int shows "push_bit n i \<ge> 0 \<longleftrightarrow> i \<ge> 0"
   by (fact push_bit_nonnegative_int_iff)
 
 lemma shiftl_lt_0: fixes i :: int shows "push_bit n i < 0 \<longleftrightarrow> i < 0"
   by (fact push_bit_negative_int_iff)
 
 lemma int_shiftl_test_bit: "bit (push_bit i n :: int) m \<longleftrightarrow> m \<ge> i \<and> bit n (m - i)"
   by (fact bit_push_bit_iff_int)
 
 lemma int_0shiftr: "drop_bit x (0 :: int) = 0"
   by (fact drop_bit_of_0)
 
 lemma int_minus1_shiftr: "drop_bit x (-1 :: int) = -1"
   by (fact drop_bit_minus_one)
 
 lemma int_shiftr_ge_0: fixes i :: int shows "drop_bit n i \<ge> 0 \<longleftrightarrow> i \<ge> 0"
   by (fact drop_bit_nonnegative_int_iff)
 
 lemma int_shiftr_lt_0 [simp]: fixes i :: int shows "drop_bit n i < 0 \<longleftrightarrow> i < 0"
   by (fact drop_bit_negative_int_iff)
 
 lemma int_shiftr_numeral [simp]:
   "drop_bit (numeral w') (1 :: int) = 0"
   "drop_bit (numeral w') (numeral num.One :: int) = 0"
   "drop_bit (numeral w') (numeral (num.Bit0 w) :: int) = drop_bit (pred_numeral w') (numeral w)"
   "drop_bit (numeral w') (numeral (num.Bit1 w) :: int) = drop_bit (pred_numeral w') (numeral w)"
   "drop_bit (numeral w') (- numeral (num.Bit0 w) :: int) = drop_bit (pred_numeral w') (- numeral w)"
   "drop_bit (numeral w') (- numeral (num.Bit1 w) :: int) = drop_bit (pred_numeral w') (- numeral (Num.inc w))"
   by (simp_all add: numeral_eq_Suc add_One drop_bit_Suc)
 
 lemma int_shiftr_numeral_Suc0 [simp]:
   "drop_bit (Suc 0) (1 :: int) = 0"
   "drop_bit (Suc 0) (numeral num.One :: int) = 0"
   "drop_bit (Suc 0) (numeral (num.Bit0 w) :: int) = numeral w"
   "drop_bit (Suc 0) (numeral (num.Bit1 w) :: int) = numeral w"
   "drop_bit (Suc 0) (- numeral (num.Bit0 w) :: int) = - numeral w"
   "drop_bit (Suc 0) (- numeral (num.Bit1 w) :: int) = - numeral (Num.inc w)"
   by (simp_all add: drop_bit_Suc add_One)
 
 lemma bin_nth_minus_p2:
   assumes sign: "bin_sign x = 0"
   and y: "y = push_bit n 1"
   and m: "m < n"
   and x: "x < y"
   shows "bit (x - y) m = bit x m"
 proof -
   from sign y x have \<open>x \<ge> 0\<close> and \<open>y = 2 ^ n\<close> and \<open>x < 2 ^ n\<close>
     by (simp_all add: bin_sign_def push_bit_eq_mult split: if_splits)
   from \<open>0 \<le> x\<close> \<open>x < 2 ^ n\<close> \<open>m < n\<close> have \<open>bit x m \<longleftrightarrow> bit (x - 2 ^ n) m\<close>
   proof (induction m arbitrary: x n)
     case 0
     then show ?case
       by simp
   next
     case (Suc m)
     moreover define q where \<open>q = n - 1\<close>
     ultimately have n: \<open>n = Suc q\<close>
       by simp
     have \<open>(x - 2 ^ Suc q) div 2 = x div 2 - 2 ^ q\<close>
       by simp
     moreover from Suc.IH [of \<open>x div 2\<close> q] Suc.prems
     have \<open>bit (x div 2) m \<longleftrightarrow> bit (x div 2 - 2 ^ q) m\<close>
       by (simp add: n)
     ultimately show ?case
       by (simp add: bit_Suc n)
   qed
   with \<open>y = 2 ^ n\<close> show ?thesis
     by simp
 qed
 
 lemma bin_clr_conv_NAND:
   "bin_sc n False i = i AND NOT (push_bit n 1)"
   by (rule bit_eqI) (auto simp add: bin_sc_eq bit_simps)
 
 lemma bin_set_conv_OR:
   "bin_sc n True i = i OR (push_bit n 1)"
   by (rule bit_eqI) (auto simp add: bin_sc_eq bit_simps)
 
 end
 
 
 subsection \<open>More lemmas on words\<close>
 
 lemma msb_conv_bin_sign:
   "msb x \<longleftrightarrow> bin_sign x = -1"
   by (simp add: bin_sign_def not_le msb_int_def)
 
-lemma msb_bin_sc [simp]:
+lemma msb_bin_sc:
   "msb (bin_sc n b x) \<longleftrightarrow> msb x"
   by (simp add: msb_conv_bin_sign)
 
 lemma msb_word_def:
   \<open>msb a \<longleftrightarrow> bin_sign (signed_take_bit (LENGTH('a) - 1) (uint a)) = - 1\<close>
   for a :: \<open>'a::len word\<close>
   by (simp add: bin_sign_def bit_simps msb_word_iff_bit)
 
 lemma word_msb_def:
   "msb a \<longleftrightarrow> bin_sign (sint a) = - 1"
   by (simp add: msb_word_def sint_uint)
 
 lemma word_rcat_eq:
   \<open>word_rcat ws = word_of_int (bin_rcat (LENGTH('a::len)) (map uint ws))\<close>
   for ws :: \<open>'a::len word list\<close>
   apply (simp add: word_rcat_def bin_rcat_def rev_map)
   apply transfer
   apply (simp add: horner_sum_foldr foldr_map comp_def)
   done
 
 lemma sign_uint_Pls [simp]: "bin_sign (uint x) = 0"
   by (simp add: sign_Pls_ge_0)
 
 lemmas bin_log_bintrs = bin_trunc_not bin_trunc_xor bin_trunc_and bin_trunc_or
 
 \<comment> \<open>following definitions require both arithmetic and bit-wise word operations\<close>
 
 \<comment> \<open>to get \<open>word_no_log_defs\<close> from \<open>word_log_defs\<close>, using \<open>bin_log_bintrs\<close>\<close>
 lemmas wils1 = bin_log_bintrs [THEN word_of_int_eq_iff [THEN iffD2],
   folded uint_word_of_int_eq, THEN eq_reflection]
 
 \<comment> \<open>the binary operations only\<close>  (* BH: why is this needed? *)
 lemmas word_log_binary_defs =
   word_and_def word_or_def word_xor_def
 
 lemma setBit_no: "Bit_Operations.set_bit n (numeral bin) = word_of_int (bin_sc n True (numeral bin))"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma clearBit_no:
   "unset_bit n (numeral bin) = word_of_int (bin_sc n False (numeral bin))"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma eq_mod_iff: "0 < n \<Longrightarrow> b = b mod n \<longleftrightarrow> 0 \<le> b \<and> b < n"
   for b n :: int
   by auto (metis pos_mod_conj)+
 
 lemma split_uint_lem: "bin_split n (uint w) = (a, b) \<Longrightarrow>
     a = take_bit (LENGTH('a) - n) a \<and> b = take_bit (LENGTH('a)) b"
   for w :: "'a::len word"
   by transfer (simp add: drop_bit_take_bit ac_simps)
 
 \<comment> \<open>limited hom result\<close>
 lemma word_cat_hom:
   "LENGTH('a::len) \<le> LENGTH('b::len) + LENGTH('c::len) \<Longrightarrow>
     (word_cat (word_of_int w :: 'b word) (b :: 'c word) :: 'a word) =
     word_of_int ((\<lambda>k n l. concat_bit n l k) w (size b) (uint b))"
   by transfer (simp add: take_bit_concat_bit_eq)
 
 lemma bintrunc_shiftl:
   "take_bit n (push_bit i m) = push_bit i (take_bit (n - i) m)"
   for m :: int
   by (fact take_bit_push_bit)
 
 lemma uint_shiftl:
   "uint (push_bit i n) = take_bit (size n) (push_bit i (uint n))"
   by (simp add: unsigned_push_bit_eq word_size)
 
 lemma bin_mask_conv_pow2:
   "mask n = 2 ^ n - (1 :: int)"
   by (fact mask_eq_exp_minus_1)
 
 lemma bin_mask_ge0: "mask n \<ge> (0 :: int)"
   by (fact mask_nonnegative_int)
 
 context
   includes bit_operations_syntax
 begin
 
 lemma and_bin_mask_conv_mod: "x AND mask n = x mod 2 ^ n"
   for x :: int
   by (simp flip: take_bit_eq_mod add: take_bit_eq_mask)
 
 end
 
 lemma bin_mask_numeral:
   "mask (numeral n) = (1 :: int) + 2 * mask (pred_numeral n)"
   by (fact mask_numeral)
 
 lemma bin_nth_mask: "bit (mask n :: int) i \<longleftrightarrow> i < n"
   by (simp add: bit_mask_iff)
 
 lemma bin_sign_mask [simp]: "bin_sign (mask n) = 0"
   by (simp add: bin_sign_def bin_mask_conv_pow2)
 
 lemma bin_mask_p1_conv_shift: "mask n + 1 = push_bit n (1 :: int)"
   by (simp add: bin_mask_conv_pow2 shiftl_int_def)
 
 lemma sbintrunc_eq_in_range:
   "((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x = x) = (x \<in> range ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n))"
   "(x = (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x) = (x \<in> range ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n))"
   apply (simp_all add: image_def)
   apply (metis sbintrunc_sbintrunc)+
   done
 
 lemma sbintrunc_If:
   "- 3 * (2 ^ n) \<le> x \<and> x < 3 * (2 ^ n)
     \<Longrightarrow> (signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) n x = (if x < - (2 ^ n) then x + 2 * (2 ^ n)
         else if x \<ge> 2 ^ n then x - 2 * (2 ^ n) else x)"
   apply (simp add: no_sbintr_alt2, safe)
    apply (simp add: mod_pos_geq)
   apply (subst mod_add_self1[symmetric], simp)
   done
 
 lemma sint_range':
   \<open>- (2 ^ (LENGTH('a) - Suc 0)) \<le> sint x \<and> sint x < 2 ^ (LENGTH('a) - Suc 0)\<close>
   for x :: \<open>'a::len word\<close>
   apply transfer
   using sbintr_ge sbintr_lt apply auto
   done
 
 lemma signed_arith_eq_checks_to_ord:
   "(sint a + sint b = sint (a + b ))
     = ((a <=s a + b) = (0 <=s b))"
   "(sint a - sint b = sint (a - b ))
     = ((0 <=s a - b) = (b <=s a))"
   "(- sint a = sint (- a)) = (0 <=s (- a) = (a <=s 0))"
   using sint_range'[where x=a] sint_range'[where x=b]
   by (simp_all add: sint_word_ariths word_sle_eq word_sless_alt sbintrunc_If)
 
 lemma signed_mult_eq_checks_double_size:
   assumes mult_le: "(2 ^ (len_of TYPE ('a) - 1) + 1) ^ 2 \<le> (2 :: int) ^ (len_of TYPE ('b) - 1)"
            and le: "2 ^ (LENGTH('a) - 1) \<le> (2 :: int) ^ (len_of TYPE ('b) - 1)"
   shows "(sint (a :: 'a :: len word) * sint b = sint (a * b))
        = (scast a * scast b = (scast (a * b) :: 'b :: len word))"
 proof -
   have P: "(signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (size a - 1) (sint a * sint b) \<in> range ((signed_take_bit :: nat \<Rightarrow> int \<Rightarrow> int) (size a - 1))"
     by simp
 
   have abs: "!! x :: 'a word. abs (sint x) < 2 ^ (size a - 1) + 1"
     apply (cut_tac x=x in sint_range')
     apply (simp add: abs_le_iff word_size)
     done
   have abs_ab: "abs (sint a * sint b) < 2 ^ (LENGTH('b) - 1)"
     using abs_mult_less[OF abs[where x=a] abs[where x=b]] mult_le
     by (simp add: abs_mult power2_eq_square word_size)
   define r s where \<open>r = LENGTH('a) - 1\<close> \<open>s = LENGTH('b) - 1\<close>
   then have \<open>LENGTH('a) = Suc r\<close> \<open>LENGTH('b) = Suc s\<close>
     \<open>size a = Suc r\<close> \<open>size b = Suc r\<close>
     by (simp_all add: word_size)
   then show ?thesis
     using P[unfolded range_sbintrunc] abs_ab le
     apply clarsimp
     apply (transfer fixing: r s)
-    apply (auto simp add: signed_take_bit_int_eq_self min.absorb2 simp flip: signed_take_bit_eq_iff_take_bit_eq)
+    apply (auto simp add: signed_take_bit_int_eq_self simp flip: signed_take_bit_eq_iff_take_bit_eq)
     done
 qed
 
 lemma bintrunc_id:
   "\<lbrakk>m \<le> int n; 0 < m\<rbrakk> \<Longrightarrow> take_bit n m = m"
-  by (simp add: take_bit_int_eq_self_iff le_less_trans less_exp)
+  by (simp add: take_bit_int_eq_self_iff le_less_trans)
 
 lemma bin_cat_cong: "concat_bit n b a = concat_bit m d c"
   if "n = m" "a = c" "take_bit m b = take_bit m d"
   using that(3) unfolding that(1,2)
   by (simp add: bin_cat_eq_push_bit_add_take_bit)
 
 lemma bin_cat_eqD1: "concat_bit n b a = concat_bit n d c \<Longrightarrow> a = c"
   by (metis drop_bit_bin_cat_eq)
 
 lemma bin_cat_eqD2: "concat_bit n b a = concat_bit n d c \<Longrightarrow> take_bit n b = take_bit n d"
   by (metis take_bit_bin_cat_eq)
 
 lemma bin_cat_inj: "(concat_bit n b a) = concat_bit n d c \<longleftrightarrow> a = c \<and> take_bit n b = take_bit n d"
   by (auto intro: bin_cat_cong bin_cat_eqD1 bin_cat_eqD2)
 
 code_identifier
   code_module Bits_Int \<rightharpoonup>
   (SML) Bit_Operations and (OCaml) Bit_Operations and (Haskell) Bit_Operations and (Scala) Bit_Operations
 
 end
diff --git a/thys/Word_Lib/Bitwise.thy b/thys/Word_Lib/Bitwise.thy
--- a/thys/Word_Lib/Bitwise.thy
+++ b/thys/Word_Lib/Bitwise.thy
@@ -1,507 +1,507 @@
 (*
  * Copyright Thomas Sewell, NICTA and Sascha Boehme, TU Muenchen
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 theory Bitwise
   imports
     "HOL-Library.Word"
     More_Arithmetic
     Reversed_Bit_Lists
     Bit_Shifts_Infix_Syntax
 begin
 
 text \<open>Helper constants used in defining addition\<close>
 
 definition xor3 :: "bool \<Rightarrow> bool \<Rightarrow> bool \<Rightarrow> bool"
   where "xor3 a b c = (a = (b = c))"
 
 definition carry :: "bool \<Rightarrow> bool \<Rightarrow> bool \<Rightarrow> bool"
   where "carry a b c = ((a \<and> (b \<or> c)) \<or> (b \<and> c))"
 
 lemma carry_simps:
   "carry True a b = (a \<or> b)"
   "carry a True b = (a \<or> b)"
   "carry a b True = (a \<or> b)"
   "carry False a b = (a \<and> b)"
   "carry a False b = (a \<and> b)"
   "carry a b False = (a \<and> b)"
   by (auto simp add: carry_def)
 
 lemma xor3_simps:
   "xor3 True a b = (a = b)"
   "xor3 a True b = (a = b)"
   "xor3 a b True = (a = b)"
   "xor3 False a b = (a \<noteq> b)"
   "xor3 a False b = (a \<noteq> b)"
   "xor3 a b False = (a \<noteq> b)"
   by (simp_all add: xor3_def)
 
 text \<open>Breaking up word equalities into equalities on their
   bit lists. Equalities are generated and manipulated in the
   reverse order to \<^const>\<open>to_bl\<close>.\<close>
 
 lemma bl_word_sub: "to_bl (x - y) = to_bl (x + (- y))"
   by simp
 
 lemma rbl_word_1: "rev (to_bl (1 :: 'a::len word)) = takefill False (LENGTH('a)) [True]"
   apply (rule_tac s="rev (to_bl (word_succ (0 :: 'a word)))" in trans)
    apply simp
   apply (simp only: rtb_rbl_ariths(1)[OF refl])
   apply simp
   apply (case_tac "LENGTH('a)")
    apply simp
   apply (simp add: takefill_alt)
   done
 
 lemma rbl_word_if: "rev (to_bl (if P then x else y)) = map2 (If P) (rev (to_bl x)) (rev (to_bl y))"
   by (simp add: split_def)
 
 lemma rbl_add_carry_Cons:
   "(if car then rbl_succ else id) (rbl_add (x # xs) (y # ys)) =
     xor3 x y car # (if carry x y car then rbl_succ else id) (rbl_add xs ys)"
   by (simp add: carry_def xor3_def)
 
 lemma rbl_add_suc_carry_fold:
   "length xs = length ys \<Longrightarrow>
     \<forall>car. (if car then rbl_succ else id) (rbl_add xs ys) =
       (foldr (\<lambda>(x, y) res car. xor3 x y car # res (carry x y car)) (zip xs ys) (\<lambda>_. [])) car"
   apply (erule list_induct2)
    apply simp
   apply (simp only: rbl_add_carry_Cons)
   apply simp
   done
 
 lemma to_bl_plus_carry:
   "to_bl (x + y) =
     rev (foldr (\<lambda>(x, y) res car. xor3 x y car # res (carry x y car))
       (rev (zip (to_bl x) (to_bl y))) (\<lambda>_. []) False)"
   using rbl_add_suc_carry_fold[where xs="rev (to_bl x)" and ys="rev (to_bl y)"]
   apply (simp add: word_add_rbl[OF refl refl])
   apply (drule_tac x=False in spec)
   apply (simp add: zip_rev)
   done
 
 definition "rbl_plus cin xs ys =
   foldr (\<lambda>(x, y) res car. xor3 x y car # res (carry x y car)) (zip xs ys) (\<lambda>_. []) cin"
 
 lemma rbl_plus_simps:
   "rbl_plus cin (x # xs) (y # ys) = xor3 x y cin # rbl_plus (carry x y cin) xs ys"
   "rbl_plus cin [] ys = []"
   "rbl_plus cin xs [] = []"
   by (simp_all add: rbl_plus_def)
 
 lemma rbl_word_plus: "rev (to_bl (x + y)) = rbl_plus False (rev (to_bl x)) (rev (to_bl y))"
   by (simp add: rbl_plus_def to_bl_plus_carry zip_rev)
 
 definition "rbl_succ2 b xs = (if b then rbl_succ xs else xs)"
 
 lemma rbl_succ2_simps:
   "rbl_succ2 b [] = []"
   "rbl_succ2 b (x # xs) = (b \<noteq> x) # rbl_succ2 (x \<and> b) xs"
   by (simp_all add: rbl_succ2_def)
 
 lemma twos_complement: "- x = word_succ (not x)"
   using arg_cong[OF word_add_not[where x=x], where f="\<lambda>a. a - x + 1"]
   by (simp add: word_succ_p1 word_sp_01[unfolded word_succ_p1] del: word_add_not)
 
 lemma rbl_word_neg: "rev (to_bl (- x)) = rbl_succ2 True (map Not (rev (to_bl x)))"
   for x :: \<open>'a::len word\<close>
   by (simp add: twos_complement word_succ_rbl[OF refl] bl_word_not rev_map rbl_succ2_def)
 
 lemma rbl_word_cat:
   "rev (to_bl (word_cat x y :: 'a::len word)) =
     takefill False (LENGTH('a)) (rev (to_bl y) @ rev (to_bl x))"
   by (simp add: word_cat_bl word_rev_tf)
 
 lemma rbl_word_slice:
   "rev (to_bl (slice n w :: 'a::len word)) =
     takefill False (LENGTH('a)) (drop n (rev (to_bl w)))"
   apply (simp add: slice_take word_rev_tf rev_take)
   apply (cases "n < LENGTH('b)", simp_all)
   done
 
 lemma rbl_word_ucast:
   "rev (to_bl (ucast x :: 'a::len word)) = takefill False (LENGTH('a)) (rev (to_bl x))"
   apply (simp add: to_bl_ucast takefill_alt)
   apply (simp add: rev_drop)
   apply (cases "LENGTH('a) < LENGTH('b)")
    apply simp_all
   done
 
 lemma rbl_shiftl:
   "rev (to_bl (w << n)) = takefill False (size w) (replicate n False @ rev (to_bl w))"
   by (simp add: bl_shiftl takefill_alt word_size rev_drop)
 
 lemma rbl_shiftr:
   "rev (to_bl (w >> n)) = takefill False (size w) (drop n (rev (to_bl w)))"
   by (simp add: shiftr_slice rbl_word_slice word_size)
 
 definition "drop_nonempty v n xs = (if n < length xs then drop n xs else [last (v # xs)])"
 
 lemma drop_nonempty_simps:
   "drop_nonempty v (Suc n) (x # xs) = drop_nonempty x n xs"
   "drop_nonempty v 0 (x # xs) = (x # xs)"
   "drop_nonempty v n [] = [v]"
   by (simp_all add: drop_nonempty_def)
 
 definition "takefill_last x n xs = takefill (last (x # xs)) n xs"
 
 lemma takefill_last_simps:
   "takefill_last z (Suc n) (x # xs) = x # takefill_last x n xs"
   "takefill_last z 0 xs = []"
   "takefill_last z n [] = replicate n z"
   by (simp_all add: takefill_last_def) (simp_all add: takefill_alt)
 
 lemma rbl_sshiftr:
   "rev (to_bl (w >>> n)) = takefill_last False (size w) (drop_nonempty False n (rev (to_bl w)))"
   apply (cases "n < size w")
    apply (simp add: bl_sshiftr takefill_last_def word_size
       takefill_alt rev_take last_rev
       drop_nonempty_def)
   apply (subgoal_tac "(w >>> n) = of_bl (replicate (size w) (msb w))")
    apply (simp add: word_size takefill_last_def takefill_alt
       last_rev word_msb_alt word_rev_tf
       drop_nonempty_def take_Cons')
    apply (case_tac "LENGTH('a)", simp_all)
   apply (rule word_eqI)
   apply (simp add: bit_simps word_size test_bit_of_bl
       msb_nth)
   done
 
 lemma nth_word_of_int:
   "bit (word_of_int x :: 'a::len word) n = (n < LENGTH('a) \<and> bit x n)"
   apply (simp add: test_bit_bl word_size to_bl_of_bin)
   apply (subst conj_cong[OF refl], erule bin_nth_bl)
   apply auto
   done
 
 lemma nth_scast:
   "bit (scast (x :: 'a::len word) :: 'b::len word) n =
     (n < LENGTH('b) \<and>
     (if n < LENGTH('a) - 1 then bit x n
      else bit x (LENGTH('a) - 1)))"
   apply transfer
   apply (auto simp add: bit_signed_take_bit_iff min_def)
   done
 
 lemma rbl_word_scast:
   "rev (to_bl (scast x :: 'a::len word)) = takefill_last False (LENGTH('a)) (rev (to_bl x))"
   apply (rule nth_equalityI)
    apply (simp add: word_size takefill_last_def)
   apply (clarsimp simp: nth_scast takefill_last_def
       nth_takefill word_size rev_nth to_bl_nth)
   apply (cases "LENGTH('b)")
    apply simp
   apply (clarsimp simp: less_Suc_eq_le linorder_not_less
       last_rev word_msb_alt[symmetric]
       msb_nth)
   done
 
 definition rbl_mul :: "bool list \<Rightarrow> bool list \<Rightarrow> bool list"
   where "rbl_mul xs ys = foldr (\<lambda>x sm. rbl_plus False (map ((\<and>) x) ys) (False # sm)) xs []"
 
 lemma rbl_mul_simps:
   "rbl_mul (x # xs) ys = rbl_plus False (map ((\<and>) x) ys) (False # rbl_mul xs ys)"
   "rbl_mul [] ys = []"
   by (simp_all add: rbl_mul_def)
 
 lemma takefill_le2: "length xs \<le> n \<Longrightarrow> takefill x m (takefill x n xs) = takefill x m xs"
   by (simp add: takefill_alt replicate_add[symmetric])
 
 lemma take_rbl_plus: "\<forall>n b. take n (rbl_plus b xs ys) = rbl_plus b (take n xs) (take n ys)"
   apply (simp add: rbl_plus_def take_zip[symmetric])
   apply (rule_tac list="zip xs ys" in list.induct)
    apply simp
   apply (clarsimp simp: split_def)
   apply (case_tac n, simp_all)
   done
 
 lemma word_rbl_mul_induct:
   "length xs \<le> size y \<Longrightarrow>
     rbl_mul xs (rev (to_bl y)) = take (length xs) (rev (to_bl (of_bl (rev xs) * y)))"
   for y :: "'a::len word"
 proof (induct xs)
   case Nil
   show ?case by (simp add: rbl_mul_simps)
 next
   case (Cons z zs)
 
   have rbl_word_plus': "to_bl (x + y) = rev (rbl_plus False (rev (to_bl x)) (rev (to_bl y)))"
     for x y :: "'a word"
     by (simp add: rbl_word_plus[symmetric])
 
   have mult_bit: "to_bl (of_bl [z] * y) = map ((\<and>) z) (to_bl y)"
     by (cases z) (simp cong: map_cong, simp add: map_replicate_const cong: map_cong)
 
   have shiftl: "of_bl xs * 2 * y = (of_bl xs * y) << 1" for xs
-    by (simp add: push_bit_eq_mult)
+    by (simp add: push_bit_eq_mult shiftl_def)
 
   have zip_take_triv: "\<And>xs ys n. n = length ys \<Longrightarrow> zip (take n xs) ys = zip xs ys"
     by (rule nth_equalityI) simp_all
 
   from Cons show ?case
     apply (simp add: trans [OF of_bl_append add.commute]
         rbl_mul_simps rbl_word_plus' distrib_right mult_bit shiftl rbl_shiftl)
     apply (simp add: takefill_alt word_size rev_map take_rbl_plus min_def)
     apply (simp add: rbl_plus_def)
     apply (simp add: zip_take_triv)
-    apply (simp only: mult.commute [of _ 2] mult.assoc to_bl_double_eq)
+    apply (simp only: mult.commute [of _ 2] to_bl_double_eq)
     apply (simp flip: butlast_rev add: take_butlast)
     done
 qed
 
 lemma rbl_word_mul: "rev (to_bl (x * y)) = rbl_mul (rev (to_bl x)) (rev (to_bl y))"
   for x :: "'a::len word"
   using word_rbl_mul_induct[where xs="rev (to_bl x)" and y=y] by (simp add: word_size)
 
 text \<open>Breaking up inequalities into bitlist properties.\<close>
 
 definition
   "rev_bl_order F xs ys =
      (length xs = length ys \<and>
        ((xs = ys \<and> F)
           \<or> (\<exists>n < length xs. drop (Suc n) xs = drop (Suc n) ys
                    \<and> \<not> xs ! n \<and> ys ! n)))"
 
 lemma rev_bl_order_simps:
   "rev_bl_order F [] [] = F"
   "rev_bl_order F (x # xs) (y # ys) = rev_bl_order ((y \<and> \<not> x) \<or> ((y \<or> \<not> x) \<and> F)) xs ys"
    apply (simp_all add: rev_bl_order_def)
   apply (rule conj_cong[OF refl])
   apply (cases "xs = ys")
    apply (simp add: nth_Cons')
    apply blast
   apply (simp add: nth_Cons')
   apply safe
    apply (rule_tac x="n - 1" in exI)
    apply simp
   apply (rule_tac x="Suc n" in exI)
   apply simp
   done
 
 lemma rev_bl_order_rev_simp:
   "length xs = length ys \<Longrightarrow>
    rev_bl_order F (xs @ [x]) (ys @ [y]) = ((y \<and> \<not> x) \<or> ((y \<or> \<not> x) \<and> rev_bl_order F xs ys))"
   by (induct arbitrary: F rule: list_induct2) (auto simp: rev_bl_order_simps)
 
 lemma rev_bl_order_bl_to_bin:
   "length xs = length ys \<Longrightarrow>
     rev_bl_order True xs ys = (bl_to_bin (rev xs) \<le> bl_to_bin (rev ys)) \<and>
     rev_bl_order False xs ys = (bl_to_bin (rev xs) < bl_to_bin (rev ys))"
   apply (induct xs ys rule: list_induct2)
    apply (simp_all add: rev_bl_order_simps bl_to_bin_app_cat concat_bit_Suc)
   apply (auto simp add: bl_to_bin_def add1_zle_eq)
   done
 
 lemma word_le_rbl: "x \<le> y \<longleftrightarrow> rev_bl_order True (rev (to_bl x)) (rev (to_bl y))"
   for x y :: "'a::len word"
   by (simp add: rev_bl_order_bl_to_bin word_le_def)
 
 lemma word_less_rbl: "x < y \<longleftrightarrow> rev_bl_order False (rev (to_bl x)) (rev (to_bl y))"
   for x y :: "'a::len word"
   by (simp add: word_less_alt rev_bl_order_bl_to_bin)
 
 definition "map_last f xs = (if xs = [] then [] else butlast xs @ [f (last xs)])"
 
 lemma map_last_simps:
   "map_last f [] = []"
   "map_last f [x] = [f x]"
   "map_last f (x # y # zs) = x # map_last f (y # zs)"
   by (simp_all add: map_last_def)
 
 lemma word_sle_rbl:
   "x <=s y \<longleftrightarrow> rev_bl_order True (map_last Not (rev (to_bl x))) (map_last Not (rev (to_bl y)))"
   using word_msb_alt[where w=x] word_msb_alt[where w=y]
   apply (simp add: word_sle_msb_le word_le_rbl)
   apply (subgoal_tac "length (to_bl x) = length (to_bl y)")
    apply (cases "to_bl x", simp)
    apply (cases "to_bl y", simp)
    apply (clarsimp simp: map_last_def rev_bl_order_rev_simp)
    apply auto
   done
 
 lemma word_sless_rbl:
   "x <s y \<longleftrightarrow> rev_bl_order False (map_last Not (rev (to_bl x))) (map_last Not (rev (to_bl y)))"
   using word_msb_alt[where w=x] word_msb_alt[where w=y]
   apply (simp add: word_sless_msb_less word_less_rbl)
   apply (subgoal_tac "length (to_bl x) = length (to_bl y)")
    apply (cases "to_bl x", simp)
    apply (cases "to_bl y", simp)
    apply (clarsimp simp: map_last_def rev_bl_order_rev_simp)
    apply auto
   done
 
 text \<open>Lemmas for unpacking \<^term>\<open>rev (to_bl n)\<close> for numerals n and also
   for irreducible values and expressions.\<close>
 
 lemma rev_bin_to_bl_simps:
   "rev (bin_to_bl 0 x) = []"
   "rev (bin_to_bl (Suc n) (numeral (num.Bit0 nm))) = False # rev (bin_to_bl n (numeral nm))"
   "rev (bin_to_bl (Suc n) (numeral (num.Bit1 nm))) = True # rev (bin_to_bl n (numeral nm))"
   "rev (bin_to_bl (Suc n) (numeral (num.One))) = True # replicate n False"
   "rev (bin_to_bl (Suc n) (- numeral (num.Bit0 nm))) = False # rev (bin_to_bl n (- numeral nm))"
   "rev (bin_to_bl (Suc n) (- numeral (num.Bit1 nm))) =
     True # rev (bin_to_bl n (- numeral (nm + num.One)))"
   "rev (bin_to_bl (Suc n) (- numeral (num.One))) = True # replicate n True"
   "rev (bin_to_bl (Suc n) (- numeral (num.Bit0 nm + num.One))) =
     True # rev (bin_to_bl n (- numeral (nm + num.One)))"
   "rev (bin_to_bl (Suc n) (- numeral (num.Bit1 nm + num.One))) =
     False # rev (bin_to_bl n (- numeral (nm + num.One)))"
   "rev (bin_to_bl (Suc n) (- numeral (num.One + num.One))) =
     False # rev (bin_to_bl n (- numeral num.One))"
   by (simp_all add: bin_to_bl_aux_append bin_to_bl_zero_aux bin_to_bl_minus1_aux replicate_append_same)
 
 lemma to_bl_upt: "to_bl x = rev (map (bit x) [0 ..< size x])"
   by (simp add: to_bl_eq_rev word_size rev_map)
 
 lemma rev_to_bl_upt: "rev (to_bl x) = map (bit x) [0 ..< size x]"
   by (simp add: to_bl_upt)
 
 lemma upt_eq_list_intros:
   "j \<le> i \<Longrightarrow> [i ..< j] = []"
   "i = x \<Longrightarrow> x < j \<Longrightarrow> [x + 1 ..< j] = xs \<Longrightarrow> [i ..< j] = (x # xs)"
   by (simp_all add: upt_eq_Cons_conv)
 
 
 subsection \<open>Tactic definition\<close>
 
 lemma if_bool_simps:
   "If p True y = (p \<or> y) \<and> If p False y = (\<not> p \<and> y) \<and>
     If p y True = (p \<longrightarrow> y) \<and> If p y False = (p \<and> y)"
   by auto
 
 ML \<open>
 structure Word_Bitwise_Tac =
 struct
 
 val word_ss = simpset_of \<^theory_context>\<open>Word\<close>;
 
 fun mk_nat_clist ns =
   fold_rev (Thm.mk_binop \<^cterm>\<open>Cons :: nat \<Rightarrow> _\<close>)
     ns \<^cterm>\<open>[] :: nat list\<close>;
 
 fun upt_conv ctxt ct =
   case Thm.term_of ct of
     \<^Const_>\<open>upt for n m\<close> =>
       let
         val (i, j) = apply2 (snd o HOLogic.dest_number) (n, m);
         val ns = map (Numeral.mk_cnumber \<^ctyp>\<open>nat\<close>) (i upto (j - 1))
           |> mk_nat_clist;
         val prop =
           Thm.mk_binop \<^cterm>\<open>(=) :: nat list \<Rightarrow> _\<close> ct ns
           |> Thm.apply \<^cterm>\<open>Trueprop\<close>;
       in
         try (fn () =>
           Goal.prove_internal ctxt [] prop
             (K (REPEAT_DETERM (resolve_tac ctxt @{thms upt_eq_list_intros} 1
                 ORELSE simp_tac (put_simpset word_ss ctxt) 1))) |> mk_meta_eq) ()
       end
   | _ => NONE;
 
 val expand_upt_simproc =
   Simplifier.make_simproc \<^context> "expand_upt"
    {lhss = [\<^term>\<open>upt x y\<close>], proc = K upt_conv};
 
 fun word_len_simproc_fn ctxt ct =
   (case Thm.term_of ct of
     \<^Const_>\<open>len_of _ for t\<close> =>
      (let
         val T = fastype_of t |> dest_Type |> snd |> the_single
         val n = Numeral.mk_cnumber \<^ctyp>\<open>nat\<close> (Word_Lib.dest_binT T);
         val prop =
           Thm.mk_binop \<^cterm>\<open>(=) :: nat \<Rightarrow> _\<close> ct n
           |> Thm.apply \<^cterm>\<open>Trueprop\<close>;
       in
         Goal.prove_internal ctxt [] prop (K (simp_tac (put_simpset word_ss ctxt) 1))
         |> mk_meta_eq |> SOME
       end handle TERM _ => NONE | TYPE _ => NONE)
   | _ => NONE);
 
 val word_len_simproc =
   Simplifier.make_simproc \<^context> "word_len"
    {lhss = [\<^term>\<open>len_of x\<close>], proc = K word_len_simproc_fn};
 
 (* convert 5 or nat 5 to Suc 4 when n_sucs = 1, Suc (Suc 4) when n_sucs = 2,
    or just 5 (discarding nat) when n_sucs = 0 *)
 
 fun nat_get_Suc_simproc_fn n_sucs ctxt ct =
   let
     val (f, arg) = dest_comb (Thm.term_of ct);
     val n =
       (case arg of \<^term>\<open>nat\<close> $ n => n | n => n)
       |> HOLogic.dest_number |> snd;
     val (i, j) = if n > n_sucs then (n_sucs, n - n_sucs) else (n, 0);
     val arg' = funpow i HOLogic.mk_Suc (HOLogic.mk_number \<^typ>\<open>nat\<close> j);
     val _ = if arg = arg' then raise TERM ("", []) else ();
     fun propfn g =
       HOLogic.mk_eq (g arg, g arg')
       |> HOLogic.mk_Trueprop |> Thm.cterm_of ctxt;
     val eq1 =
       Goal.prove_internal ctxt [] (propfn I)
         (K (simp_tac (put_simpset word_ss ctxt) 1));
   in
     Goal.prove_internal ctxt [] (propfn (curry (op $) f))
       (K (simp_tac (put_simpset HOL_ss ctxt addsimps [eq1]) 1))
     |> mk_meta_eq |> SOME
   end handle TERM _ => NONE;
 
 fun nat_get_Suc_simproc n_sucs ts =
   Simplifier.make_simproc \<^context> "nat_get_Suc"
    {lhss = map (fn t => t $ \<^term>\<open>n :: nat\<close>) ts,
     proc = K (nat_get_Suc_simproc_fn n_sucs)};
 
 val no_split_ss =
   simpset_of (put_simpset HOL_ss \<^context>
     |> Splitter.del_split @{thm if_split});
 
 val expand_word_eq_sss =
   (simpset_of (put_simpset HOL_basic_ss \<^context> addsimps
        @{thms word_eq_rbl_eq word_le_rbl word_less_rbl word_sle_rbl word_sless_rbl}),
   map simpset_of [
    put_simpset no_split_ss \<^context> addsimps
     @{thms rbl_word_plus rbl_word_and rbl_word_or rbl_word_not
                                 rbl_word_neg bl_word_sub rbl_word_xor
                                 rbl_word_cat rbl_word_slice rbl_word_scast
                                 rbl_word_ucast rbl_shiftl rbl_shiftr rbl_sshiftr
                                 rbl_word_if},
    put_simpset no_split_ss \<^context> addsimps
     @{thms to_bl_numeral to_bl_neg_numeral to_bl_0 rbl_word_1},
    put_simpset no_split_ss \<^context> addsimps
     @{thms rev_rev_ident rev_replicate rev_map to_bl_upt word_size}
           addsimprocs [word_len_simproc],
    put_simpset no_split_ss \<^context> addsimps
     @{thms list.simps split_conv replicate.simps list.map
                                 zip_Cons_Cons zip_Nil drop_Suc_Cons drop_0 drop_Nil
                                 foldr.simps list.map zip.simps(1) zip_Nil zip_Cons_Cons takefill_Suc_Cons
                                 takefill_Suc_Nil takefill.Z rbl_succ2_simps
                                 rbl_plus_simps rev_bin_to_bl_simps append.simps
                                 takefill_last_simps drop_nonempty_simps
                                 rev_bl_order_simps}
           addsimprocs [expand_upt_simproc,
                        nat_get_Suc_simproc 4
                          [\<^term>\<open>replicate\<close>, \<^term>\<open>takefill x\<close>,
                           \<^term>\<open>drop\<close>, \<^term>\<open>bin_to_bl\<close>,
                           \<^term>\<open>takefill_last x\<close>,
                           \<^term>\<open>drop_nonempty x\<close>]],
     put_simpset no_split_ss \<^context> addsimps @{thms xor3_simps carry_simps if_bool_simps}
   ])
 
 fun tac ctxt =
   let
     val (ss, sss) = expand_word_eq_sss;
   in
     foldr1 (op THEN_ALL_NEW)
       ((CHANGED o safe_full_simp_tac (put_simpset ss ctxt)) ::
         map (fn ss => safe_full_simp_tac (put_simpset ss ctxt)) sss)
   end;
 
 end
 \<close>
 
 method_setup word_bitwise =
   \<open>Scan.succeed (fn ctxt => Method.SIMPLE_METHOD (Word_Bitwise_Tac.tac ctxt 1))\<close>
   "decomposer for word equalities and inequalities into bit propositions"
 
 end
diff --git a/thys/Word_Lib/Examples.thy b/thys/Word_Lib/Examples.thy
--- a/thys/Word_Lib/Examples.thy
+++ b/thys/Word_Lib/Examples.thy
@@ -1,584 +1,1194 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 theory Examples
   imports
     Bit_Shifts_Infix_Syntax Next_and_Prev Signed_Division_Word Bitwise
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 section \<open>\<^typ>\<open>nat\<close>\<close>
 
 lemma
-  \<open>\<not> bit (1 :: nat) (Suc (Suc (Suc 0)))\<close>
-  by simp
-
-lemma
-  \<open>\<not> bit (1 :: nat) 3\<close>
-  by simp
-
-lemma
   \<open>bit (1705 :: nat) (Suc (Suc (Suc 0)))\<close>
   by simp
 
 lemma
   \<open>bit (1705 :: nat) 3\<close>
   by simp
 
 lemma
+  \<open>\<not> bit (1 :: nat) (Suc (Suc (Suc 0)))\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (1 :: nat) 3\<close>
+  by simp
+
+lemma
   \<open>(1705 :: nat) AND 42 = 40\<close>
   by simp
 
 lemma
+  \<open>(1705 :: nat) AND Suc 0 = 1\<close>
+  by simp
+
+lemma
   \<open>(1705 :: nat) OR 42 = 1707\<close>
   by simp
 
 lemma
+  \<open>(1705 :: nat) OR Suc 0 = 1705\<close>
+  by simp
+
+lemma
   \<open>(1705 :: nat) XOR 42 = 1667\<close>
   by simp
 
 lemma
+  \<open>(1705 :: nat) XOR 1 = 1704\<close>
+  by simp
+
+lemma
   \<open>push_bit 3 (1705 :: nat) = 13640\<close>
   by simp
 
 lemma
   \<open>push_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 13640\<close>
   by simp
 
 lemma
+  \<open>push_bit 3 (Suc 0) = 8\<close>
+  by simp
+
+lemma
+  \<open>push_bit (Suc (Suc (Suc 0))) (Suc 0) = 8\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: nat) << 3 = 13640\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: nat) << Suc (Suc (Suc 0)) = 13640\<close>
+  by simp
+
+lemma
+  \<open>Suc 0 << 3 = 8\<close>
+  by simp
+
+lemma
+  \<open>Suc 0 << Suc (Suc (Suc 0)) = 8\<close>
+  by simp
+
+lemma
   \<open>drop_bit 3 (1705 :: nat) = 213\<close>
   by simp
 
 lemma
   \<open>drop_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 213\<close>
   by simp
 
 lemma
+  \<open>drop_bit 3 (Suc 0) = 0\<close>
+  by simp
+
+lemma
+  \<open>drop_bit (Suc (Suc (Suc 0))) (Suc 0) = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: nat) >> 3 = 213\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: nat) >> Suc (Suc (Suc 0)) = 213\<close>
+  by simp
+
+lemma
+  \<open>Suc 0 >> 3 = 0\<close>
+  by simp
+
+lemma
+  \<open>Suc 0 >> Suc (Suc (Suc 0)) = 0\<close>
+  by simp
+
+lemma
   \<open>take_bit 3 (1705 :: nat) = 1\<close>
   by simp
 
 lemma
   \<open>take_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 1\<close>
   by simp
 
+lemma
+  \<open>take_bit 3 (Suc 0) = 1\<close>
+  by simp
+
+lemma
+  \<open>take_bit (Suc (Suc (Suc 0))) (Suc 0) = 1\<close>
+  by simp
+
+
 section \<open>\<^typ>\<open>int\<close>\<close>
 
 lemma
+  \<open>bit (1705 :: int) (Suc (Suc (Suc 0)))\<close>
+  by simp
+
+lemma
+  \<open>bit (1705 :: int) 3\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (- 1705 :: int) (Suc (Suc (Suc 0)))\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (- 1705 :: int) 3\<close>
+  by simp
+
+lemma
   \<open>\<not> bit (1 :: int) (Suc (Suc (Suc 0)))\<close>
   by simp
 
 lemma
   \<open>\<not> bit (1 :: int) 3\<close>
   by simp
 
 lemma
-  \<open>bit (1705 :: int) (Suc (Suc (Suc 0)))\<close>
-  by simp
-
-lemma
-  \<open>bit (1705 :: int) 3\<close>
-  by simp
-
-lemma
   \<open>(NOT 1705 :: int) = - 1706\<close>
   by simp
 
 lemma
   \<open>(NOT (- 42 :: int)) = 41\<close>
   by simp
 
 lemma
+  \<open>(NOT 1 :: int) = - 2\<close>
+  by simp
+
+lemma
   \<open>(1705 :: int) AND 42 = 40\<close>
   by simp
 
 lemma
   \<open>(1705 :: int) AND - 42 = 1664\<close>
   by simp
 
 lemma
+  \<open>(1705 :: int) AND 1 = 1\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: int) AND 42 = 2\<close>
   by simp
 
 lemma
   \<open>- (1705 :: int) AND - 42 = - 1706\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: int) AND 1 = 1\<close>
+  by simp
+
+lemma
   \<open>(1705 :: int) OR 42 = 1707\<close>
   by simp
 
 lemma
   \<open>(1705 :: int) OR - 42 = - 1\<close>
   by simp
 
 lemma
+  \<open>(1705 :: int) OR 1 = 1705\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: int) OR 42 = - 1665\<close>
   by simp
 
 lemma
   \<open>- (1705 :: int) OR - 42 = - 41\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: int) OR 1 = - 1705\<close>
+  by simp
+
+lemma
   \<open>(1705 :: int) XOR 42 = 1667\<close>
   by simp
 
 lemma
   \<open>(1705 :: int) XOR - 42 = - 1665\<close>
   by simp
 
 lemma
+  \<open>(1705 :: int) XOR 1 = 1704\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: int) XOR 42 = - 1667\<close>
   by simp
 
 lemma
   \<open>- (1705 :: int) XOR - 42 = 1665\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: int) XOR 1 = - 1706\<close>
+  by simp
+
+lemma
   \<open>push_bit 3 (1705 :: int) = 13640\<close>
   by simp
 
 lemma
   \<open>push_bit (Suc (Suc (Suc 0))) (1705 :: int) = 13640\<close>
   by simp
 
 lemma
   \<open>push_bit 3 (- 1705 :: int) = - 13640\<close>
   by simp
 
 lemma
   \<open>push_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = - 13640\<close>
   by simp
 
 lemma
+  \<open>push_bit 3 (1 :: int) = 8\<close>
+  by simp
+
+lemma
+  \<open>push_bit (Suc (Suc (Suc 0))) (1 :: int) = 8\<close>
+  by simp
+
+lemma
+  \<open>push_bit 3 (- 1 :: int) = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>push_bit (Suc (Suc (Suc 0))) (- 1 :: int) = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>(1705 :: int) << 3  = 13640\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: int) << Suc (Suc (Suc 0)) = 13640\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: int) << 3 = - 13640\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: int) << Suc (Suc (Suc 0)) = - 13640\<close>
+  by simp
+
+lemma
+  \<open>(1 :: int) << 3 = 8\<close>
+  by simp
+
+lemma
+  \<open>(1 :: int) << Suc (Suc (Suc 0)) = 8\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: int) << 3 = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>(- 1 :: int) << Suc (Suc (Suc 0)) = - 8\<close>
+  by simp
+
+lemma
   \<open>drop_bit 3 (1705 :: int) = 213\<close>
   by simp
 
 lemma
   \<open>drop_bit (Suc (Suc (Suc 0))) (1705 :: int) = 213\<close>
   by simp
 
 lemma
   \<open>drop_bit 3 (- 1705 :: int) = - 214\<close>
   by simp
 
 lemma
   \<open>drop_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = - 214\<close>
   by simp
 
 lemma
+  \<open>drop_bit 3 (1 :: int) = 0\<close>
+  by simp
+
+lemma
+  \<open>drop_bit (Suc (Suc (Suc 0))) (1 :: int) = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: int) >> 3 = 213\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: int) >> Suc (Suc (Suc 0)) = 213\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: int) >> 3 = - 214\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: int) >> Suc (Suc (Suc 0)) = - 214\<close>
+  by simp
+
+lemma
+  \<open>(1 :: int) >> 3 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1 :: int) >> Suc (Suc (Suc 0)) = 0\<close>
+  by simp
+
+lemma
   \<open>take_bit 3 (1705 :: int) = 1\<close>
   by simp
 
 lemma
   \<open>take_bit (Suc (Suc (Suc 0))) (1705 :: int) = 1\<close>
   by simp
 
 lemma
   \<open>take_bit 3 (- 1705 :: int) = 7\<close>
   by simp
 
 lemma
   \<open>take_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = 7\<close>
   by simp
 
 lemma
+  \<open>take_bit 3 (1 :: int) = 1\<close>
+  by simp
+
+lemma
+  \<open>take_bit (Suc (Suc (Suc 0))) (1 :: int) = 1\<close>
+  by simp
+
+lemma
+  \<open>take_bit 3 (- 1 :: int) = 7\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>take_bit (Suc (Suc (Suc 0))) (- 1 :: int) = 7\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
   \<open>signed_take_bit 3 (1705 :: int) = - 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit (Suc (Suc (Suc 0))) (1705 :: int) = - 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit 3 (- 1705 :: int) = 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = 7\<close>
   by simp
 
+lemma
+  \<open>signed_take_bit 3 (1 :: int) = 1\<close>
+  by simp
+
+lemma
+  \<open>signed_take_bit (Suc (Suc (Suc 0))) (1 :: int) = 1\<close>
+  by simp
+
+
 section \<open>\<^typ>\<open>'a word\<close>\<close>
 
 lemma
-  \<open>\<not> bit (1 :: 'a::len word) (Suc (Suc (Suc 0)))\<close>
+  \<open>(1705 :: 8 word) = 169\<close>
   by simp
 
 lemma
-  \<open>\<not> bit (1 :: 'a::len word) 3\<close>
+  \<open>(- 1705 :: 8 word) = 87\<close>
+  by simp
+
+lemma
+  \<open>(257 :: 8 word) = 1\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) \<le> 1705\<close>
+  by simp
+
+lemma
+  \<open>(- 42 :: 8 word) \<le> 230\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) \<le> - 1705\<close>
+  by simp
+
+lemma
+  \<open>- (42 :: 8 word) \<le> 235\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 8 word) \<le> 1705\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 8 word) \<le> 65535\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) < 1705\<close>
+  by simp
+
+lemma
+  \<open>(- 42 :: 8 word) < 230\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) < - 1705\<close>
+  by simp
+
+lemma
+  \<open>- (42 :: 8 word) < 230\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 8 word) < 1705\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 8 word) < - 1\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) \<le>s 1333\<close>
+  by simp
+
+lemma
+  \<open>(- 42 :: 8 word) \<le>s 230\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) \<le>s - 1705\<close>
+  by simp
+
+lemma
+  \<open>- (42 :: 8 word) \<le>s - 1705\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 8 word) \<le>s 42\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) <s 1333\<close>
+  by simp
+
+lemma
+  \<open>(- 42 :: 8 word) <s 230\<close>
+  by simp
+
+lemma
+  \<open>(42 :: 8 word) <s - 1705\<close>
+  by simp
+
+lemma
+  \<open>- (42 :: 8 word) <s - 1705\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 8 word) <s 42\<close>
   by simp
 
 lemma
   \<open>bit (1705 :: 16 word) (Suc (Suc (Suc 0)))\<close>
   by simp
 
 lemma
   \<open>bit (1705 :: 16 word) 3\<close>
   by simp
 
 lemma
+  \<open>\<not> bit (- 1705 :: 16 word) (Suc (Suc (Suc 0)))\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (- 1705 :: 16 word) 3\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (1 :: 'a::len word) (Suc (Suc (Suc 0)))\<close>
+  by simp
+
+lemma
+  \<open>\<not> bit (1 :: 'a::len word) 3\<close>
+  by simp
+
+lemma
   \<open>(NOT 1705 :: 'a::len word) = - 1706\<close>
   by simp
 
 lemma
   \<open>(NOT (- 42 :: 'a::len word)) = 41\<close>
   by simp
 
 lemma
+  \<open>(NOT 1 :: 'a::len word) = - 2\<close>
+  by simp
+
+lemma
   \<open>(1705 :: 'a::len word) AND 42 = 40\<close>
   by simp
 
 lemma
   \<open>(1705 :: 'a::len word) AND - 42 = 1664\<close>
   by simp
 
 lemma
+  \<open>(1705 :: 'a::len word) AND 1 = 1\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: 'a::len word) AND 42 = 2\<close>
   by simp
 
 lemma
   \<open>- (1705 :: 'a::len word) AND - 42 = - 1706\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: 'a::len word) AND 1 = 1\<close>
+  by simp
+
+lemma
   \<open>(1705 :: 'a::len word) OR 42 = 1707\<close>
   by simp
 
 lemma
   \<open>(1705 :: 'a::len word) OR - 42 = - 1\<close>
   by simp
 
 lemma
+  \<open>(1705 :: 'a::len word) OR 1 = 1705\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: 'a::len word) OR 42 = - 1665\<close>
   by simp
 
 lemma
   \<open>- (1705 :: 'a::len word) OR - 42 = - 41\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: 'a::len word) OR 1 = - 1705\<close>
+  by simp
+
+lemma
   \<open>(1705 :: 'a::len word) XOR 42 = 1667\<close>
   by simp
 
 lemma
   \<open>(1705 :: 'a::len word) XOR - 42 = - 1665\<close>
   by simp
 
 lemma
+  \<open>(1705 :: 'a::len word) XOR 1 = 1704\<close>
+  by simp
+
+lemma
   \<open>- (1705 :: 'a::len word) XOR 42 = - 1667\<close>
   by simp
 
 lemma
   \<open>- (1705 :: 'a::len word) XOR - 42 = 1665\<close>
   by simp
 
 lemma
+  \<open>- (1705 :: 'a::len word) XOR 1 = - 1706\<close>
+  by simp
+
+lemma
   \<open>push_bit 3 (1705 :: 'a::len word) = 13640\<close>
   by simp
 
 lemma
   \<open>push_bit (Suc (Suc (Suc 0))) (1705 :: 'a::len word) = 13640\<close>
   by simp
 
 lemma
   \<open>push_bit 3 (- 1705 :: 'a::len word) = - 13640\<close>
   by simp
 
 lemma
   \<open>push_bit (Suc (Suc (Suc 0))) (- 1705 :: 'a::len word) = - 13640\<close>
   by simp
 
 lemma
+  \<open>push_bit 3 (1 :: 'a::len word) = 8\<close>
+  by simp
+
+lemma
+  \<open>push_bit (Suc (Suc (Suc 0))) (1 :: 'a::len word) = 8\<close>
+  by simp
+
+lemma
+  \<open>push_bit 3 (- 1 :: 'a::len word) = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>push_bit (Suc (Suc (Suc 0))) (- 1 :: 'a::len word) = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>(1705 :: 'a::len word) << 3 = 13640\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 'a::len word) << Suc (Suc (Suc 0)) = 13640\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 'a::len word) << 3 = - 13640\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 'a::len word) << Suc (Suc (Suc 0)) = - 13640\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 'a::len word) << 3 = 8\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 'a::len word) << Suc (Suc (Suc 0)) = 8\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 'a::len word) << 3 = - 8\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>(- 1 :: 'a::len word) << Suc (Suc (Suc 0)) = - 8\<close>
+  by simp
+
+lemma
   \<open>drop_bit 3 (1705 :: 16 word) = 213\<close>
   by simp
 
 lemma
   \<open>drop_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 213\<close>
   by simp
 
 lemma
   \<open>drop_bit 3 (- 1705 :: 16 word) = 7978\<close>
   by simp
 
 lemma
   \<open>drop_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7978\<close>
   by simp
 
 lemma
+  \<open>drop_bit 3 (1 :: 16 word) = 0\<close>
+  by simp
+
+lemma
+  \<open>drop_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) >> 3 = 213\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) >> Suc (Suc (Suc 0)) = 213\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) >> 3 = 7978\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) >> Suc (Suc (Suc 0)) = 7978\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) >> 3 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) >> Suc (Suc (Suc 0)) = 0\<close>
+  by simp
+
+lemma
   \<open>signed_drop_bit 3 (1705 :: 16 word) = 213\<close>
   by simp
 
 lemma
   \<open>signed_drop_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 213\<close>
   by simp
 
 lemma
   \<open>signed_drop_bit 3 (- 1705 :: 16 word) = - 214\<close>
   by simp
 
 lemma
   \<open>signed_drop_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = - 214\<close>
   by simp
 
 lemma
+  \<open>signed_drop_bit 3 (1 :: 16 word) = 0\<close>
+  by simp
+
+lemma
+  \<open>signed_drop_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) >>> 3 = 213\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) >>> Suc (Suc (Suc 0)) = 213\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) >>> 3 = - 214\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) >>> Suc (Suc (Suc 0)) = - 214\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) >>> 3 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) >>> Suc (Suc (Suc 0)) = 0\<close>
+  by simp
+
+lemma
   \<open>take_bit 3 (1705 :: 16 word) = 1\<close>
   by simp
 
 lemma
   \<open>take_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 1\<close>
   by simp
 
 lemma
   \<open>take_bit 3 (- 1705 :: 16 word) = 7\<close>
   by simp
 
 lemma
   \<open>take_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7\<close>
   by simp
 
 lemma
+  \<open>take_bit 3 (1 :: 16 word) = 1\<close>
+  by simp
+
+lemma
+  \<open>take_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 1\<close>
+  by simp
+
+lemma
+  \<open>take_bit 3 (- 1 :: 16 word) = 7\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
+  \<open>take_bit (Suc (Suc (Suc 0))) (- 1 :: 16 word) = 7\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma
   \<open>signed_take_bit 3 (1705 :: 16 word) = - 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = - 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit 3 (- 1705 :: 16 word) = 7\<close>
   by simp
 
 lemma
   \<open>signed_take_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7\<close>
   by simp
 
+lemma
+  \<open>signed_take_bit 3 (1 :: 16 word) = 1\<close>
+  by simp
+
+lemma
+  \<open>signed_take_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 1\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) div 42 = 40\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) div 42 = 1519\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) div - 42 = 0\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) div - 42 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) div 1 = 1705\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) div - 1 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) div 42 = 0\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 16 word) div 42 = 1560\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) mod 42 = 25\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) mod 42 = 33\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) mod - 42 = 1705\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) mod - 42 = 63831\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) mod 1 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) mod - 1 = 1705\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) mod 42 = 1\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 16 word) mod 42 = 15\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) sdiv 42 = 40\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) sdiv 42 = 65496\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) sdiv - 42 = 65496\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) sdiv - 42 = 40\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) sdiv 1 = 1705\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) sdiv - 1 = 63831\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) sdiv 42 = 0\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 16 word) sdiv 42 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) smod 42 = 25\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) smod 42 = 65511\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) smod - 42 = 25\<close>
+  by simp
+
+lemma
+  \<open>(- 1705 :: 16 word) smod - 42 = 65511\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) smod 1 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1705 :: 16 word) smod - 1 = 0\<close>
+  by simp
+
+lemma
+  \<open>(1 :: 16 word) smod 42 = 1\<close>
+  by simp
+
+lemma
+  \<open>(- 1 :: 16 word) smod 42 = 65535\<close>
+  by simp
+
 text "modulus"
 
 lemma "(27 :: 4 word) = -5" by simp
 
 lemma "(27 :: 4 word) = 11" by simp
 
 lemma "27 \<noteq> (11 :: 6 word)" by simp
 
 text "signed"
 
 lemma "(127 :: 6 word) = -1" by simp
 
 text "number ring simps"
 
 lemma
   "27 + 11 = (38::'a::len word)"
   "27 + 11 = (6::5 word)"
   "7 * 3 = (21::'a::len word)"
   "11 - 27 = (-16::'a::len word)"
   "- (- 11) = (11::'a::len word)"
   "-40 + 1 = (-39::'a::len word)"
   by simp_all
 
 lemma "word_pred 2 = 1" by simp
 
 lemma "word_succ (- 3) = -2" by simp
 
 lemma "23 < (27::8 word)" by simp
 lemma "23 \<le> (27::8 word)" by simp
 lemma "\<not> 23 < (27::2 word)" by simp
 lemma "0 < (4::3 word)" by simp
 lemma "1 < (4::3 word)" by simp
 lemma "0 < (1::3 word)" by simp
 
 text "ring operations"
 
 lemma "a + 2 * b + c - b = (b + c) + (a :: 32 word)" by simp
 
 text "casting"
 
 lemma "uint (234567 :: 10 word) = 71" by simp
 lemma "uint (-234567 :: 10 word) = 953" by simp
 lemma "sint (234567 :: 10 word) = 71" by simp
 lemma "sint (-234567 :: 10 word) = -71" by simp
 lemma "uint (1 :: 10 word) = 1" by simp
 
 lemma "unat (-234567 :: 10 word) = 953" by simp
 lemma "unat (1 :: 10 word) = 1" by simp
 
 lemma "ucast (0b1010 :: 4 word) = (0b10 :: 2 word)" by simp
 lemma "ucast (0b1010 :: 4 word) = (0b1010 :: 10 word)" by simp
 lemma "scast (0b1010 :: 4 word) = (0b111010 :: 6 word)" by simp
 lemma "ucast (1 :: 4 word) = (1 :: 2 word)" by simp
 
 text "reducing goals to nat or int and arith:"
 lemma "i < x \<Longrightarrow> i < i + 1" for i x :: "'a::len word"
   by unat_arith
 lemma "i < x \<Longrightarrow> i < i + 1" for i x :: "'a::len word"
   by unat_arith
 
 text "bit operations"
 
 lemma "0b110 AND 0b101 = (0b100 :: 32 word)" by simp
 lemma "0b110 OR 0b011 = (0b111 :: 8 word)" by simp
 lemma "0xF0 XOR 0xFF = (0x0F :: 8 word)" by simp
 lemma "NOT (0xF0 :: 16 word) = 0xFF0F" by simp
 lemma "0 AND 5 = (0 :: 8 word)" by simp
 lemma "1 AND 1 = (1 :: 8 word)" by simp
 lemma "1 AND 0 = (0 :: 8 word)" by simp
 lemma "1 AND 5 = (1 :: 8 word)" by simp
 lemma "1 OR 6 = (7 :: 8 word)" by simp
 lemma "1 OR 1 = (1 :: 8 word)" by simp
 lemma "1 XOR 7 = (6 :: 8 word)" by simp
 lemma "1 XOR 1 = (0 :: 8 word)" by simp
 lemma "NOT 1 = (254 :: 8 word)" by simp
 lemma "NOT 0 = (255 :: 8 word)" by simp
 
 lemma "(-1 :: 32 word) = 0xFFFFFFFF" by simp
 
 lemma "bit (0b0010 :: 4 word) 1" by simp
 lemma "\<not> bit (0b0010 :: 4 word) 0" by simp
 lemma "\<not> bit (0b1000 :: 3 word) 4" by simp
 lemma "\<not> bit (1 :: 3 word) 2" by simp
 
 lemma "bit (0b11000 :: 10 word) n = (n = 4 \<or> n = 3)"
   by (auto simp add: bit_numeral_rec bit_1_iff split: nat.splits)
 
 lemma "set_bit 55 7 True = (183::'a::len word)" by simp
 lemma "set_bit 0b0010 7 True = (0b10000010::'a::len word)" by simp
 lemma "set_bit 0b0010 1 False = (0::'a::len word)" by simp
 lemma "set_bit 1 3 True = (0b1001::'a::len word)" by simp
 lemma "set_bit 1 0 False = (0::'a::len word)" by simp
 lemma "set_bit 0 3 True = (0b1000::'a::len word)" by simp
 lemma "set_bit 0 3 False = (0::'a::len word)" by simp
 
 lemma "odd (0b0101::'a::len word)" by simp
 lemma "even (0b1000::'a::len word)" by simp
 lemma "odd (1::'a::len word)" by simp
 lemma "even (0::'a::len word)" by simp
 
 lemma "\<not> msb (0b0101::4 word)" by simp
 lemma   "msb (0b1000::4 word)" by simp
 lemma "\<not> msb (1::4 word)" by simp
 lemma "\<not> msb (0::4 word)" by simp
 
 lemma "word_cat (27::4 word) (27::8 word) = (2843::'a::len word)"
   by simp
 lemma "word_cat (0b0011::4 word) (0b1111::6word) = (0b0011001111 :: 10 word)"
   by simp
 
 lemma "0b1011 << 2 = (0b101100::'a::len word)" by simp
 lemma "0b1011 >> 2 = (0b10::8 word)" by simp
 lemma "0b1011 >>> 2 = (0b10::8 word)" by simp
 lemma "1 << 2 = (0b100::'a::len word)" apply simp? oops
 
 lemma "slice 3 (0b101111::6 word) = (0b101::3 word)" by simp
 lemma "slice 3 (1::6 word) = (0::3 word)" apply simp? oops
 
 lemma "word_rotr 2 0b0110 = (0b1001::4 word)" by simp
 lemma "word_rotl 1 0b1110 = (0b1101::4 word)" by simp
 lemma "word_roti 2 0b1110 = (0b1011::4 word)" by simp
 lemma "word_roti (- 2) 0b0110 = (0b1001::4 word)" by simp
 lemma "word_rotr 2 0 = (0::4 word)" by simp
 lemma "word_rotr 2 1 = (0b0100::4 word)" apply simp? oops
 lemma "word_rotl 2 1 = (0b0100::4 word)" apply simp? oops
 lemma "word_roti (- 2) 1 = (0b0100::4 word)" apply simp? oops
 
 lemma "(x AND 0xff00) OR (x AND 0x00ff) = (x::16 word)"
 proof -
   have "(x AND 0xff00) OR (x AND 0x00ff) = x AND (0xff00 OR 0x00ff)"
     by (simp only: word_ao_dist2)
   also have "0xff00 OR 0x00ff = (-1::16 word)"
     by simp
   also have "x AND -1 = x"
     by simp
   finally show ?thesis .
 qed
 
 lemma "word_next (2:: 8 word) = 3" by eval
 lemma "word_next (255:: 8 word) = 255" by eval
 lemma "word_prev (2:: 8 word) = 1" by eval
 lemma "word_prev (0:: 8 word) = 0" by eval
 
 text \<open>singed division\<close>
 
 lemma
   "( 4 :: 32 word) sdiv  4 =  1"
   "(-4 :: 32 word) sdiv  4 = -1"
   "(-3 :: 32 word) sdiv  4 =  0"
   "( 3 :: 32 word) sdiv -4 =  0"
   "(-3 :: 32 word) sdiv -4 =  0"
   "(-5 :: 32 word) sdiv -4 =  1"
   "( 5 :: 32 word) sdiv -4 = -1"
   by (simp_all add: sdiv_word_def signed_divide_int_def)
 
 lemma
   "( 4 :: 32 word) smod  4 =   0"
   "( 3 :: 32 word) smod  4 =   3"
   "(-3 :: 32 word) smod  4 =  -3"
   "( 3 :: 32 word) smod -4 =   3"
   "(-3 :: 32 word) smod -4 =  -3"
   "(-5 :: 32 word) smod -4 =  -1"
   "( 5 :: 32 word) smod -4 =   1"
   by (simp_all add: smod_word_def signed_modulo_int_def signed_divide_int_def)
 
 
 text \<open>comparison\<close>
 
 lemma "1 < (1024::32 word) \<and> 1 \<le> (1024::32 word)"
   by simp
 
 text "bool lists"
 
 lemma "of_bl [True, False, True, True] = (0b1011::'a::len word)" by simp
 
 lemma "to_bl (0b110::4 word) = [False, True, True, False]" by simp
 
 lemma "of_bl (replicate 32 True) = (0xFFFFFFFF::32 word)"
   by (simp add: numeral_eq_Suc)
 
 text "proofs using bitwise expansion"
 
 lemma "(x AND 0xff00) OR (x AND 0x00ff) = (x::16 word)"
   by word_bitwise
 
 lemma "(x AND NOT 3) >> 4 << 2 = ((x >> 2) AND NOT 3)"
   for x :: "10 word"
   by word_bitwise
 
 lemma "((x AND -8) >> 3) AND 7 = (x AND 56) >> 3"
   for x :: "12 word"
   by word_bitwise
 
 text "some problems require further reasoning after bit expansion"
 
 lemma "x \<le> 42 \<Longrightarrow> x \<le> 89"
   for x :: "8 word"
   apply word_bitwise
   apply blast
   done
 
 lemma "(x AND 1023) = 0 \<Longrightarrow> x \<le> -1024"
   for x :: \<open>32 word\<close>
   apply word_bitwise
   apply clarsimp
   done
 
 text "operations like shifts by non-numerals will expose some internal list
  representations but may still be easy to solve"
 
 lemma shiftr_overflow: "32 \<le> a \<Longrightarrow> b >> a = 0"
   for b :: \<open>32 word\<close>
   apply word_bitwise
   apply simp
   done
 
 (* testing for presence of word_bitwise *)
 lemma "((x :: 32 word) >> 3) AND 7 = (x AND 56) >> 3"
   by word_bitwise
 
 end
 
 end
diff --git a/thys/Word_Lib/Generic_set_bit.thy b/thys/Word_Lib/Generic_set_bit.thy
--- a/thys/Word_Lib/Generic_set_bit.thy
+++ b/thys/Word_Lib/Generic_set_bit.thy
@@ -1,123 +1,124 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (* Author: Jeremy Dawson, NICTA *)
 
 section \<open>Operation variant for setting and unsetting bits\<close>
 
 theory Generic_set_bit
   imports
     "HOL-Library.Word"
     Most_significant_bit
 begin
 
 class set_bit = semiring_bits +
   fixes set_bit :: \<open>'a \<Rightarrow> nat \<Rightarrow> bool \<Rightarrow> 'a\<close>
   assumes bit_set_bit_iff_2n:
     \<open>bit (set_bit a m b) n \<longleftrightarrow>
       (if m = n then b else bit a n) \<and> 2 ^ n \<noteq> 0\<close>
 
 lemmas bit_set_bit_iff[bit_simps] = bit_set_bit_iff_2n[simplified fold_possible_bit simp_thms]
 
 lemma set_bit_eq:
   \<open>set_bit a n b = (if b then Bit_Operations.set_bit else unset_bit) n a\<close>
   for a :: \<open>'a::{ring_bit_operations, set_bit}\<close>
   by (rule bit_eqI) (simp add: bit_simps)
 
 instantiation int :: set_bit
 begin
 
 definition set_bit_int :: \<open>int \<Rightarrow> nat \<Rightarrow> bool \<Rightarrow> int\<close>
   where \<open>set_bit_int i n b = (if b then Bit_Operations.set_bit else Bit_Operations.unset_bit) n i\<close>
 
 instance
   by standard (simp_all add: set_bit_int_def bit_simps)
 
 end
 
 instantiation word :: (len) set_bit
 begin
 
 definition set_bit_word :: \<open>'a word \<Rightarrow> nat \<Rightarrow> bool \<Rightarrow> 'a word\<close>
   where set_bit_unfold: \<open>set_bit w n b = (if b then Bit_Operations.set_bit n w else unset_bit n w)\<close>
   for w :: \<open>'a::len word\<close>
 
 instance
   by standard (auto simp add: set_bit_unfold bit_simps dest: bit_imp_le_length)
 
 end
 
 lemma bit_set_bit_word_iff [bit_simps]:
   \<open>bit (set_bit w m b) n \<longleftrightarrow> (if m = n then n < LENGTH('a) \<and> b else bit w n)\<close>
   for w :: \<open>'a::len word\<close>
   by (auto simp add: bit_simps dest: bit_imp_le_length)
 
 lemma test_bit_set_gen:
   "bit (set_bit w n x) m \<longleftrightarrow> (if m = n then n < size w \<and> x else bit w m)"
   for w :: "'a::len word"
   by (simp add: bit_set_bit_word_iff word_size)
 
 lemma test_bit_set:
   "bit (set_bit w n x) n \<longleftrightarrow> n < size w \<and> x"
   for w :: "'a::len word"
   by (auto simp add: bit_simps word_size)
 
 lemma word_set_nth: "set_bit w n (bit w n) = w"
   for w :: "'a::len word"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma word_set_set_same [simp]: "set_bit (set_bit w n x) n y = set_bit w n y"
   for w :: "'a::len word"
   by (rule word_eqI) (simp add : test_bit_set_gen word_size)
 
 lemma word_set_set_diff:
   fixes w :: "'a::len word"
   assumes "m \<noteq> n"
   shows "set_bit (set_bit w m x) n y = set_bit (set_bit w n y) m x"
   by (rule word_eqI) (auto simp: test_bit_set_gen word_size assms)
 
 lemma word_set_nth_iff: "set_bit w n b = w \<longleftrightarrow> bit w n = b \<or> n \<ge> size w"
   for w :: "'a::len word"
   apply (rule iffI)
    apply (rule disjCI)
    apply (drule word_eqD)
    apply (erule sym [THEN trans])
    apply (simp add: test_bit_set)
   apply (erule disjE)
    apply clarsimp
   apply (rule word_eqI)
    apply (clarsimp simp add : test_bit_set_gen)
    apply (auto simp add: word_size)
   apply (rule bit_eqI)
   apply (simp add: bit_simps)
   done
 
 lemma word_clr_le: "w \<ge> set_bit w n False"
   for w :: "'a::len word"
   apply (simp add: set_bit_unfold)
   apply transfer
   apply (simp add: take_bit_unset_bit_eq unset_bit_less_eq)
   done
 
 lemma word_set_ge: "w \<le> set_bit w n True"
   for w :: "'a::len word"
   apply (simp add: set_bit_unfold)
   apply transfer
   apply (simp add: take_bit_set_bit_eq set_bit_greater_eq)
   done
 
 lemma set_bit_beyond:
   "size x \<le> n \<Longrightarrow> set_bit x n b = x" for x :: "'a :: len word"
   by (simp add: word_set_nth_iff)
 
-lemma one_bit_shiftl: "set_bit 0 n True = push_bit n (1 :: 'a :: len word)"
+lemma one_bit_shiftl: "set_bit 0 n True = (1 :: 'a :: len word) << n"
   apply (rule word_eqI)
   apply (auto simp add: word_size bit_simps)
   done
 
-lemmas one_bit_pow = trans [OF one_bit_shiftl push_bit_of_1]
+lemma one_bit_pow: "set_bit 0 n True = (2 :: 'a :: len word) ^ n"
+  by (simp add: one_bit_shiftl shiftl_def)
 
 end
diff --git a/thys/Word_Lib/Guide.thy b/thys/Word_Lib/Guide.thy
--- a/thys/Word_Lib/Guide.thy
+++ b/thys/Word_Lib/Guide.thy
@@ -1,432 +1,414 @@
 (*
  * Copyright Florian Haftmann
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (*<*)
 theory Guide
   imports Word_Lib_Sumo Word_64 Ancient_Numeral
 begin
 
 context semiring_bit_operations
 begin
 
 lemma bit_eq_iff:
   \<open>a = b \<longleftrightarrow> (\<forall>n. 2 ^ n \<noteq> 0 \<longrightarrow> bit a n \<longleftrightarrow> bit b n)\<close>
   using bit_eq_iff [of a b] by (simp add: possible_bit_def)
 
 end
 
-notation (output)  push_bit (\<open>push'_bit\<close>)
-
-notation (output)  drop_bit (\<open>drop'_bit\<close>)
-
-notation (output)  signed_drop_bit (\<open>signed'_drop'_bit\<close>)
-
 notation (output)  Generic_set_bit.set_bit (\<open>Generic'_set'_bit.set'_bit\<close>)
 
-hide_const (open) Generic_set_bit.set_bit push_bit drop_bit signed_drop_bit
+hide_const (open) Generic_set_bit.set_bit
 
 no_notation bit  (infixl \<open>!!\<close> 100)
 
-abbreviation \<open>push_bit n a \<equiv> a << n\<close>
-
-abbreviation \<open>drop_bit n a \<equiv> a >> n\<close>
-
-abbreviation \<open>signed_drop_bit n a \<equiv> a >>> n\<close>
-
 (*>*)
 section \<open>A short overview over bit operations and word types\<close>
 
 subsection \<open>Key principles\<close>
 
 text \<open>
   When formalizing bit operations, it is tempting to represent
   bit values as explicit lists over a binary type. This however
   is a bad idea, mainly due to the inherent ambiguities in
   representation concerning repeating leading bits.
 
   Hence this approach avoids such explicit lists altogether
   following an algebraic path:
 
     \<^item> Bit values are represented by numeric types: idealized
       unbounded bit values can be represented by type \<^typ>\<open>int\<close>,
       bounded bit values by quotient types over \<^typ>\<open>int\<close>, aka \<^typ>\<open>'a word\<close>.
 
     \<^item> (A special case are idealized unbounded bit values ending
       in @{term [source] 0} which can be represented by type \<^typ>\<open>nat\<close> but
       only support a restricted set of operations).
 
   The fundamental principles are developed in theory \<^theory>\<open>HOL.Bit_Operations\<close>
   (which is part of \<^theory>\<open>Main\<close>):
 
     \<^item> Multiplication by \<^term>\<open>2 :: int\<close> is a bit shift to the left and
 
     \<^item> Division by \<^term>\<open>2 :: int\<close> is a bit shift to the right.
 
     \<^item> Concerning bounded bit values, iterated shifts to the left
     may result in eliminating all bits by shifting them all
     beyond the boundary.  The property \<^prop>\<open>(2 :: int) ^ n \<noteq> 0\<close>
     represents that \<^term>\<open>n\<close> is \<^emph>\<open>not\<close> beyond that boundary.
 
     \<^item> The projection on a single bit is then @{thm [mode=iff] bit_iff_odd [where ?'a = int, no_vars]}.
 
     \<^item> This leads to the most fundamental properties of bit values:
 
       \<^item> Equality rule: @{thm [display, mode=iff] bit_eq_iff [where ?'a = int, no_vars]}
 
       \<^item> Induction rule: @{thm [display, mode=iff] bits_induct [where ?'a = int, no_vars]}
 
     \<^item> Characteristic properties @{prop [source] \<open>bit (f x) n \<longleftrightarrow> P x n\<close>}
       are available in fact collection \<^text>\<open>bit_simps\<close>.
 
-  On top of this, the following generic operations are provided::
+  On top of this, the following generic operations are provided:
 
     \<^item> Singleton \<^term>\<open>n\<close>th bit: \<^term>\<open>(2 :: int) ^ n\<close>
 
     \<^item> Bit mask upto bit \<^term>\<open>n\<close>: @{thm mask_eq_exp_minus_1 [where ?'a = int, no_vars]}
 
     \<^item> Left shift: @{thm push_bit_eq_mult [where ?'a = int, no_vars]}
 
     \<^item> Right shift: @{thm drop_bit_eq_div [where ?'a = int, no_vars]}
 
     \<^item> Truncation: @{thm take_bit_eq_mod [where ?'a = int, no_vars]}
 
     \<^item> Bitwise negation: @{thm [mode=iff] bit_not_iff_eq [where ?'a = int, no_vars]}
 
     \<^item> Bitwise conjunction: @{thm [mode=iff] bit_and_iff [where ?'a = int, no_vars]}
 
     \<^item> Bitwise disjunction: @{thm [mode=iff] bit_or_iff [where ?'a = int, no_vars]}
 
     \<^item> Bitwise exclusive disjunction: @{thm [mode=iff] bit_xor_iff [where ?'a = int, no_vars]}
 
     \<^item> Setting a single bit: @{thm set_bit_def [where ?'a = int, no_vars]}
 
     \<^item> Unsetting a single bit: @{thm unset_bit_def [where ?'a = int, no_vars]}
 
     \<^item> Flipping a single bit: @{thm flip_bit_def [where ?'a = int, no_vars]}
 
     \<^item> Signed truncation, or modulus centered around \<^term>\<open>0::int\<close>:
         @{thm [display] signed_take_bit_def [where ?'a = int, no_vars]}
 
     \<^item> (Bounded) conversion from and to a list of bits:
         @{thm [display] horner_sum_bit_eq_take_bit [where ?'a = int, no_vars]}
 
   Bit concatenation on \<^typ>\<open>int\<close> as given by 
     @{thm [display] concat_bit_def [no_vars]}
   appears quite
   technical but is the logical foundation for the quite natural bit concatenation
   on \<^typ>\<open>'a word\<close> (see below).
 \<close>
 
 subsection \<open>Core word theory\<close>
 
 text \<open>
   Proper word types are introduced in theory \<^theory>\<open>HOL-Library.Word\<close>, with
   the following specific operations:
 
     \<^item> Standard arithmetic:
         @{term \<open>(+) :: 'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>},
         @{term \<open>uminus :: 'a::len word \<Rightarrow> 'a word\<close>},
         @{term \<open>(-) :: 'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>},
         @{term \<open>(*) :: 'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>},
         @{term \<open>0 :: 'a::len word\<close>}, @{term \<open>1 :: 'a::len word\<close>}, numerals etc.
 
     \<^item> Standard bit operations: see above.
 
     \<^item> Conversion with unsigned interpretation of words:
 
         \<^item> @{term [source] \<open>unsigned :: 'a::len word \<Rightarrow> 'b::semiring_1\<close>}
 
         \<^item> Important special cases as abbreviations:
 
             \<^item> @{term [source] \<open>unat :: 'a::len word \<Rightarrow> nat\<close>}
 
             \<^item> @{term [source] \<open>uint :: 'a::len word \<Rightarrow> int\<close>}
 
             \<^item> @{term [source] \<open>ucast :: 'a::len word \<Rightarrow> 'b::len word\<close>}
 
     \<^item> Conversion with signed interpretation of words:
 
         \<^item> @{term [source] \<open>signed :: 'a::len word \<Rightarrow> 'b::ring_1\<close>}
 
         \<^item> Important special cases as abbreviations:
 
             \<^item> @{term [source] \<open>sint :: 'a::len word \<Rightarrow> int\<close>}
 
             \<^item> @{term [source] \<open>scast :: 'a::len word \<Rightarrow> 'b::len word\<close>}
 
     \<^item> Operations with unsigned interpretation of words:
 
         \<^item> @{thm [mode=iff] word_le_nat_alt [no_vars]}
 
         \<^item> @{thm [mode=iff] word_less_nat_alt [no_vars]}
 
         \<^item> @{thm unat_div_distrib [no_vars]}
 
         \<^item> @{thm unat_drop_bit_eq [no_vars]}
 
         \<^item> @{thm unat_mod_distrib [no_vars]}
 
         \<^item> @{thm [mode=iff] udvd_iff_dvd [no_vars]}
 
     \<^item> Operations with signed interpretation of words:
 
         \<^item> @{thm [mode=iff] word_sle_eq [no_vars]}
 
         \<^item> @{thm [mode=iff] word_sless_alt [no_vars]}
 
         \<^item> @{thm sint_signed_drop_bit_eq [no_vars]}
 
     \<^item> Rotation and reversal:
 
         \<^item> @{term [source] \<open>word_rotl :: nat \<Rightarrow> 'a::len word \<Rightarrow> 'a word\<close>}
 
         \<^item> @{term [source] \<open>word_rotr :: nat \<Rightarrow> 'a::len word \<Rightarrow> 'a word\<close>}
 
         \<^item> @{term [source] \<open>word_roti :: int \<Rightarrow> 'a::len word \<Rightarrow> 'a word\<close>}
 
         \<^item> @{term [source] \<open>word_reverse :: 'a::len word \<Rightarrow> 'a word\<close>}
 
     \<^item> Concatenation: @{term [source, display] \<open>word_cat :: 'a::len word \<Rightarrow> 'b::len word \<Rightarrow> 'c::len word\<close>}
 
   For proofs about words the following default strategies are applicable:
 
-    \<^item> Using bit extensionality (facts \<^text>\<open>bit_eq_iff\<close>, \<^text>\<open>bit_eqI\<close>; fact
+    \<^item> Using bit extensionality (facts \<^text>\<open>bit_eq_iff\<close>, \<^text>\<open>bit_word_eqI\<close>; fact
       collection \<^text>\<open>bit_simps\<close>).
 
     \<^item> Using the @{method transfer} method.
 \<close>
 
+
 subsection \<open>More library theories\<close>
 
 text \<open>
-  Note: currently, the theories listed here are hardly separate
+  Note: currently, most theories listed here are hardly separate
   entities since they import each other in various ways.
   Always inspect them to understand what you pull in if you
   want to import one.
 
     \<^descr>[Syntax]
 
       \<^descr>[\<^theory>\<open>Word_Lib.Syntax_Bundles\<close>]
         Bundles to provide alternative syntax for various bit operations.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Hex_Words\<close>]
         Printing word numerals as hexadecimal numerals.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Type_Syntax\<close>]
         Pretty type-sensitive syntax for cast operations.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_Syntax\<close>]
         Specific ASCII syntax for prominent bit operations on word.
 
     \<^descr>[Proof tools]
 
       \<^descr>[\<^theory>\<open>Word_Lib.Norm_Words\<close>]
         Rewriting word numerals to normal forms.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Bitwise\<close>]
         Method @{method word_bitwise} decomposes word equalities and inequalities into bit propositions.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Bitwise_Signed\<close>]
         Method @{method word_bitwise_signed} decomposes word equalities and inequalities into bit propositions.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_EqI\<close>]
         Method @{method word_eqI_solve} decomposes word equalities and inequalities into bit propositions.
 
     \<^descr>[Operations]
 
       \<^descr>[\<^theory>\<open>Word_Lib.Signed_Division_Word\<close>]
 
         Signed division on word:
 
           \<^item> @{term [source] \<open>(sdiv) :: 'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>}
 
           \<^item> @{term [source] \<open>(smod) :: 'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Aligned\<close>] \
 
           \<^item> @{thm [mode=iff] is_aligned_iff_udvd [no_vars]}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Least_significant_bit\<close>]
 
         The least significant bit as an alias:
         @{thm [mode=iff] lsb_odd [where ?'a = int, no_vars]}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Most_significant_bit\<close>]
 
         The most significant bit:
 
           \<^item> @{thm [mode=iff] msb_int_def [of k]}
 
           \<^item> @{thm [mode=iff] word_msb_sint [no_vars]}
 
           \<^item> @{thm [mode=iff] msb_word_iff_sless_0 [no_vars]}
 
           \<^item> @{thm [mode=iff] msb_word_iff_bit [no_vars]}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Bit_Shifts_Infix_Syntax\<close>]
 
-        Abbreviations for bit shifts decorated with
-        traditional infix syntax:
+        Bit shifts decorated with infix syntax:
 
-          \<^item> @{abbrev shiftl}
+          \<^item> @{thm Bit_Shifts_Infix_Syntax.shiftl_def [no_vars]}
 
-          \<^item> @{abbrev shiftr}
+          \<^item> @{thm Bit_Shifts_Infix_Syntax.shiftr_def [no_vars]}
 
-          \<^item> @{abbrev sshiftr}
+          \<^item> @{thm Bit_Shifts_Infix_Syntax.sshiftr_def [no_vars]}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Next_and_Prev\<close>] \
 
           \<^item> @{thm word_next_unfold [no_vars]}
 
           \<^item> @{thm word_prev_unfold [no_vars]}
 
       \<^descr>[\<^theory>\<open>Word_Lib.Enumeration_Word\<close>]
 
         More on explicit enumeration of word types.
 
       \<^descr>[\<^theory>\<open>Word_Lib.More_Word_Operations\<close>]
 
         Even more operations on word.
 
     \<^descr>[Types]
 
       \<^descr>[\<^theory>\<open>Word_Lib.Signed_Words\<close>]
 
           Formal tagging of word types with a \<^text>\<open>signed\<close> marker.
 
     \<^descr>[Lemmas]
 
       \<^descr>[\<^theory>\<open>Word_Lib.More_Word\<close>]
 
           More lemmas on words.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_Lemmas\<close>]
 
           More lemmas on words, covering many other theories mentioned here.
 
     \<^descr>[Words of popular lengths].
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_8\<close>]
 
           for 8-bit words.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_16\<close>]
 
           for 16-bit words.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_32\<close>]
 
           for 32-bit words.
 
       \<^descr>[\<^theory>\<open>Word_Lib.Word_64\<close>]
 
           for 64-bit words. This theory is not part of \<^text>\<open>Word_Lib_Sumo\<close>, because it shadows
           names from \<^theory>\<open>Word_Lib.Word_32\<close>. They can be used together, but then require
           to use qualified names in applications.
 \<close>
 
 
 subsection \<open>More library sessions\<close>
 
 text \<open>
   \<^descr>[\<^text>\<open>Native_Word\<close>] Makes machine words and machine arithmetic available for code generation.
   It provides a common abstraction that hides the differences between the different target languages.
   The code generator maps these operations to the APIs of the target languages.
 \<close>
 
 subsection \<open>Legacy theories\<close>
 
 text \<open>
   The following theories contain material which has been
   factored out since it is not recommended to use it in
   new applications, mostly because matters can be expressed
   succinctly using already existing operations.
 
   This section gives some indication how to migrate away
   from those theories.  However theorem coverage may still
   be terse in some cases.
 
   \<^descr>[\<^theory>\<open>Word_Lib.Word_Lib_Sumo\<close>]
 
     An entry point importing any relevant theory in that session.  Intended
     for backward compatibility: start importing this theory when
     migrating applications to Isabelle2021, and later sort out
     what you really need. You may need to include
    \<^theory>\<open>Word_Lib.Word_64\<close> separately.
 
   \<^descr>[\<^theory>\<open>Word_Lib.Generic_set_bit\<close>]
 
     Kind of an alias: @{thm set_bit_eq [no_vars]}
 
   \<^descr>[\<^theory>\<open>Word_Lib.Typedef_Morphisms\<close>]
 
     A low-level extension to HOL typedef providing
     conversions along type morphisms.  The @{method transfer} method
     seems to be sufficient for most applications though.
 
   \<^descr>[\<^theory>\<open>Word_Lib.Bit_Comprehension\<close>]
 
     Comprehension syntax for bit values over predicates
     \<^typ>\<open>nat \<Rightarrow> bool\<close>.  For \<^typ>\<open>'a::len word\<close>, straightforward
     alternatives exist; difficult to handle for \<^typ>\<open>int\<close>.
 
   \<^descr>[\<^theory>\<open>Word_Lib.Reversed_Bit_Lists\<close>]
 
     Representation of bit values as explicit list in
     \<^emph>\<open>reversed\<close> order.
 
     This should rarely be necessary: the \<^const>\<open>bit\<close> projection
     should be sufficient in most cases.  In case explicit lists
     are needed, existing operations can be used:
 
     @{thm [display] horner_sum_bit_eq_take_bit [where ?'a = int, no_vars]}
 
   \<^descr>[\<^theory>\<open>Word_Lib.Many_More\<close>]
 
     Collection of operations and theorems which are kept for backward
     compatibility and not used in other theories in session \<^text>\<open>Word_Lib\<close>.
     They are used in applications of \<^text>\<open>Word_Lib\<close>, but should be migrated to there.
 \<close>
 
 section \<open>Changelog\<close>
 
 text \<open>
   \<^descr>[Changes since AFP 2021] ~
 
     \<^item> Theory \<^theory>\<open>Word_Lib.Ancient_Numeral\<close> is no part of \<^theory>\<open>Word_Lib.Word_Lib_Sumo\<close>
       any longer.
 
     \<^item> Infix syntax for \<^term>\<open>(AND)\<close>, \<^term>\<open>(OR)\<close>, \<^term>\<open>(XOR)\<close> organized in
       syntax bundle \<^bundle>\<open>bit_operations_syntax\<close>.
 
     \<^item> Abbreviation \<^abbrev>\<open>max_word\<close> moved from distribution into theory
       \<^theory>\<open>Word_Lib.Legacy_Aliases\<close>.
 
     \<^item> Operation \<^const>\<open>test_bit\<close> replaced by input abbreviation \<^abbrev>\<open>test_bit\<close>.
 
-    \<^item> Operation \<^const>\<open>shiftl\<close> replaced by abbreviation \<^abbrev>\<open>shiftl\<close>.
-
-    \<^item> Operation \<^const>\<open>shiftr\<close> replaced by abbreviation \<^abbrev>\<open>shiftr\<close>.
-
-    \<^item> Operation \<^const>\<open>sshiftr\<close> replaced by abbreviation \<^abbrev>\<open>sshiftr\<close>.
-
     \<^item> Abbreviations \<^abbrev>\<open>bin_nth\<close>, \<^abbrev>\<open>bin_last\<close>, \<^abbrev>\<open>bin_rest\<close>,
       \<^abbrev>\<open>bintrunc\<close>, \<^abbrev>\<open>sbintrunc\<close>, \<^abbrev>\<open>norm_sint\<close>,
       \<^abbrev>\<open>bin_cat\<close> moved into theory \<^theory>\<open>Word_Lib.Legacy_Aliases\<close>.
 
     \<^item> Operations \<^abbrev>\<open>bshiftr1\<close>,
       \<^abbrev>\<open>setBit\<close>, \<^abbrev>\<open>clearBit\<close> moved from distribution into theory
       \<^theory>\<open>Word_Lib.Legacy_Aliases\<close> and replaced by input abbreviations.
 
     \<^item> Operations \<^const>\<open>shiftl1\<close>, \<^const>\<open>shiftr1\<close>, \<^const>\<open>sshiftr1\<close>
       moved here from distribution.
 
     \<^item> Operation \<^const>\<open>complement\<close> replaced by input abbreviation \<^abbrev>\<open>complement\<close>.
 \<close>
 
 (*<*)
 end
 (*>*)
diff --git a/thys/Word_Lib/More_Arithmetic.thy b/thys/Word_Lib/More_Arithmetic.thy
--- a/thys/Word_Lib/More_Arithmetic.thy
+++ b/thys/Word_Lib/More_Arithmetic.thy
@@ -1,137 +1,143 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section \<open>Arithmetic lemmas\<close>
 
 theory More_Arithmetic
   imports Main "HOL-Library.Type_Length"
 begin
 
 lemma n_less_equal_power_2:
   "n < 2 ^ n"
   by (fact less_exp)
 
 lemma min_pm [simp]: "min a b + (a - b) = a"
   for a b :: nat
   by arith
 
 lemma min_pm1 [simp]: "a - b + min a b = a"
   for a b :: nat
   by arith
 
 lemma rev_min_pm [simp]: "min b a + (a - b) = a"
   for a b :: nat
   by arith
 
 lemma rev_min_pm1 [simp]: "a - b + min b a = a"
   for a b :: nat
   by arith
 
 lemma min_minus [simp]: "min m (m - k) = m - k"
   for m k :: nat
   by arith
 
 lemma min_minus' [simp]: "min (m - k) m = m - k"
   for m k :: nat
   by arith
 
 lemma nat_less_power_trans:
   fixes n :: nat
   assumes nv: "n < 2 ^ (m - k)"
   and     kv: "k \<le> m"
   shows "2 ^ k * n < 2 ^ m"
 proof (rule order_less_le_trans)
   show "2 ^ k * n < 2 ^ k * 2 ^ (m - k)"
     by (rule mult_less_mono2 [OF nv zero_less_power]) simp
   show "(2::nat) ^ k * 2 ^ (m - k) \<le> 2 ^ m" using nv kv
     by (subst power_add [symmetric]) simp
 qed
 
 lemma nat_le_power_trans:
   fixes n :: nat
   shows "\<lbrakk>n \<le> 2 ^ (m - k); k \<le> m\<rbrakk> \<Longrightarrow> 2 ^ k * n \<le> 2 ^ m"
   by (metis le_add_diff_inverse mult_le_mono2 semiring_normalization_rules(26))
 
 lemma nat_add_offset_less:
   fixes x :: nat
   assumes yv: "y < 2 ^ n"
   and     xv: "x < 2 ^ m"
   and     mn: "sz = m + n"
   shows   "x * 2 ^ n + y < 2 ^ sz"
 proof (subst mn)
   from yv obtain qy where "y + qy = 2 ^ n" and "0 < qy"
     by (auto dest: less_imp_add_positive)
 
   have "x * 2 ^ n + y < x * 2 ^ n + 2 ^ n" by simp fact+
   also have "\<dots> = (x + 1) * 2 ^ n" by simp
   also have "\<dots> \<le> 2 ^ (m + n)" using xv
     by (subst power_add) (rule mult_le_mono1, simp)
   finally show "x * 2 ^ n + y < 2 ^ (m + n)" .
 qed
 
 lemma nat_power_less_diff:
   assumes lt: "(2::nat) ^ n * q < 2 ^ m"
   shows "q < 2 ^ (m - n)"
   using lt
 proof (induct n arbitrary: m)
   case 0
   then show ?case by simp
 next
   case (Suc n)
 
   have ih: "\<And>m. 2 ^ n * q < 2 ^ m \<Longrightarrow> q < 2 ^ (m - n)"
     and prem: "2 ^ Suc n * q < 2 ^ m" by fact+
 
   show ?case
   proof (cases m)
     case 0
     then show ?thesis using Suc by simp
   next
     case (Suc m')
     then show ?thesis using prem
       by (simp add: ac_simps ih)
   qed
 qed
 
 lemma power_2_mult_step_le:
   "\<lbrakk>n' \<le> n; 2 ^ n' * k' < 2 ^ n * k\<rbrakk> \<Longrightarrow> 2 ^ n' * (k' + 1) \<le> 2 ^ n * (k::nat)"
   apply (cases "n'=n", simp)
    apply (metis Suc_leI le_refl mult_Suc_right mult_le_mono semiring_normalization_rules(7))
   apply (drule (1) le_neq_trans)
   apply clarsimp
   apply (subgoal_tac "\<exists>m. n = n' + m")
    prefer 2
    apply (simp add: le_Suc_ex)
   apply (clarsimp simp: power_add)
   apply (metis Suc_leI mult.assoc mult_Suc_right nat_mult_le_cancel_disj)
   done
 
 lemma nat_mult_power_less_eq:
   "b > 0 \<Longrightarrow> (a * b ^ n < (b :: nat) ^ m) = (a < b ^ (m - n))"
   using mult_less_cancel2[where m = a and k = "b ^ n" and n="b ^ (m - n)"]
         mult_less_cancel2[where m="a * b ^ (n - m)" and k="b ^ m" and n=1]
   apply (simp only: power_add[symmetric] nat_minus_add_max)
   apply (simp only: power_add[symmetric] nat_minus_add_max ac_simps)
   apply (simp add: max_def split: if_split_asm)
   done
 
 lemma diff_diff_less:
   "(i < m - (m - (n :: nat))) = (i < m \<and> i < n)"
   by auto
 
 lemma small_powers_of_2:
   \<open>x < 2 ^ (x - 1)\<close> if \<open>x \<ge> 3\<close> for x :: nat
 proof -
   define m where \<open>m = x - 3\<close>
   with that have \<open>x = m + 3\<close>
     by simp
   moreover have \<open>m + 3 < 4 * 2 ^ m\<close>
     by (induction m) simp_all
   ultimately show ?thesis
     by simp
 qed
 
+lemma msrevs:
+  "0 < n \<Longrightarrow> (k * n + m) div n = m div n + k"
+  "(k * n + m) mod n = m mod n"
+  for n :: nat
+  by simp_all
+
 end
diff --git a/thys/Word_Lib/More_Word.thy b/thys/Word_Lib/More_Word.thy
--- a/thys/Word_Lib/More_Word.thy
+++ b/thys/Word_Lib/More_Word.thy
@@ -1,2547 +1,2975 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section \<open>Lemmas on words\<close>
 
 theory More_Word
   imports
     "HOL-Library.Word"
     More_Arithmetic
     More_Divides
 begin
 
+context ring_bit_operations
+begin
+
+context
+  includes bit_operations_syntax
+begin
+
+lemma push_bit_mask_eq: \<comment> \<open>TODO move\<close>
+  \<open>push_bit m (mask n) = mask (n + m) AND NOT (mask m)\<close>
+  apply (rule bit_eqI)
+  apply (auto simp add: bit_simps not_less possible_bit_def)
+  apply (drule sym [of 0])
+  apply (simp only:)
+  using exp_not_zero_imp_exp_diff_not_zero apply (blast dest: exp_not_zero_imp_exp_diff_not_zero)
+  done
+
+end
+
+end
+
+text \<open>\<close> \<comment> \<open>TODO move\<close>
+
+context semiring_1
+begin
+
+lemma numeral_num_of_nat_unfold:
+  \<open>numeral (num_of_nat n) = (if n = 0 then 1 else of_nat n)\<close>
+  by (induction n) (simp_all add: numeral_inc ac_simps)
+
+lemma num_of_nat_numeral_eq [simp]:
+  \<open>num_of_nat (numeral q) = q\<close>
+proof (induction q)
+  case One
+  then show ?case
+    by simp
+next
+  case (Bit0 q)
+  then show ?case
+    apply (simp only: Num.numeral_Bit0 Num.numeral_add)
+    apply (subst num_of_nat_double)
+     apply simp_all
+    done
+next
+  case (Bit1 q)
+  then show ?case
+    apply (simp only: Num.numeral_Bit1 Num.numeral_add)
+    apply (subst num_of_nat_plus_distrib)
+      apply simp
+     apply simp
+    apply (subst num_of_nat_double)
+     apply simp_all
+    done
+qed
+
+end
+
+definition take_bit_num :: \<open>nat \<Rightarrow> num \<Rightarrow> num option\<close>
+  where \<open>take_bit_num n m =
+    (if take_bit n (numeral m ::nat) = 0 then None else Some (num_of_nat (take_bit n (numeral m ::nat))))\<close>
+
+lemma take_bit_num_simps [code]:
+  \<open>take_bit_num 0 m = None\<close>
+  \<open>take_bit_num (Suc n) Num.One =
+    Some Num.One\<close>
+  \<open>take_bit_num (Suc n) (Num.Bit0 m) =
+    (case take_bit_num n m of None \<Rightarrow> None | Some q \<Rightarrow> Some (Num.Bit0 q))\<close>
+  \<open>take_bit_num (Suc n) (Num.Bit1 m) =
+    Some (case take_bit_num n m of None \<Rightarrow> Num.One | Some q \<Rightarrow> Num.Bit1 q)\<close>
+  by (auto simp add: take_bit_num_def ac_simps mult_2 num_of_nat_double)
+
+lemma take_bit_num_numeral_simps:
+  \<open>take_bit_num (numeral n) Num.One =
+    Some Num.One\<close>
+  \<open>take_bit_num (numeral n) (Num.Bit0 m) =
+    (case take_bit_num (pred_numeral n) m of None \<Rightarrow> None | Some q \<Rightarrow> Some (Num.Bit0 q))\<close>
+  \<open>take_bit_num (numeral n) (Num.Bit1 m) =
+    Some (case take_bit_num (pred_numeral n) m of None \<Rightarrow> Num.One | Some q \<Rightarrow> Num.Bit1 q)\<close>
+  by (auto simp add: take_bit_num_def ac_simps mult_2 num_of_nat_double)
+
+context semiring_bit_operations
+begin
+
+lemma take_bit_num_eq_None_imp:
+  \<open>take_bit m (numeral n) = 0\<close> if \<open>take_bit_num m n = None\<close>
+proof -
+  from that have \<open>take_bit m (numeral n :: nat) = 0\<close>
+    by (simp add: take_bit_num_def split: if_splits)
+  then have \<open>of_nat (take_bit m (numeral n)) = of_nat 0\<close>
+    by simp
+  then show ?thesis
+    by (simp add: of_nat_take_bit)
+qed
+    
+lemma take_bit_num_eq_Some_imp:
+  \<open>take_bit m (numeral n) = numeral q\<close> if \<open>take_bit_num m n = Some q\<close>
+proof -
+  from that have \<open>take_bit m (numeral n :: nat) = numeral q\<close>
+    by (auto simp add: take_bit_num_def More_Word.numeral_num_of_nat_unfold split: if_splits)
+  then have \<open>of_nat (take_bit m (numeral n)) = of_nat (numeral q)\<close>
+    by simp
+  then show ?thesis
+    by (simp add: of_nat_take_bit)
+qed
+
+lemma take_bit_numeral_numeral:
+  \<open>take_bit (numeral m) (numeral n) =
+    (case take_bit_num (numeral m) n of None \<Rightarrow> 0 | Some q \<Rightarrow> numeral q)\<close>
+  by (auto split: option.split dest: take_bit_num_eq_None_imp take_bit_num_eq_Some_imp)
+
+end
+
+lemma take_bit_numeral_minus_numeral_int:
+  \<open>take_bit (numeral m) (- numeral n :: int) =
+    (case take_bit_num (numeral m) n of None \<Rightarrow> 0 | Some q \<Rightarrow> take_bit (numeral m) (2 ^ numeral m - numeral q))\<close> (is \<open>?lhs = ?rhs\<close>)
+proof (cases \<open>take_bit_num (numeral m) n\<close>)
+  case None
+  then show ?thesis
+    by (auto dest: take_bit_num_eq_None_imp [where ?'a = int] simp add: take_bit_eq_0_iff)
+next
+  case (Some q)
+  then have q: \<open>take_bit (numeral m) (numeral n :: int) = numeral q\<close>
+    by (auto dest: take_bit_num_eq_Some_imp)
+  let ?T = \<open>take_bit (numeral m) :: int \<Rightarrow> int\<close>
+  have *: \<open>?T (2 ^ numeral m) = ?T (?T 0)\<close>
+    by (simp add: take_bit_eq_0_iff)
+  have \<open>?lhs = ?T (0 - numeral n)\<close>
+    by simp
+  also have \<open>\<dots> = ?T (?T (?T 0) - ?T (?T (numeral n)))\<close>
+    by (simp only: take_bit_diff)
+  also have \<open>\<dots> = ?T (2 ^ numeral m - ?T (numeral n))\<close>
+    by (simp only: take_bit_diff flip: *)
+  also have \<open>\<dots> = ?rhs\<close>
+    by (simp add: q Some)
+  finally show ?thesis .
+qed
+
+lemma take_bit_numeral_minus_numeral_word:
+  \<open>take_bit (numeral m) (- numeral n :: 'a::len word) =
+    (case take_bit_num (numeral m) n of None \<Rightarrow> 0 | Some q \<Rightarrow> take_bit (numeral m) (2 ^ numeral m - numeral q))\<close> (is \<open>?lhs = ?rhs\<close>)
+proof (cases \<open>LENGTH('a) \<le> numeral m\<close>)
+  case True
+  then have *: \<open>(take_bit (numeral m) :: 'a word \<Rightarrow> 'a word) = id\<close>
+    by (simp add: fun_eq_iff take_bit_word_eq_self)
+  have **: \<open>2 ^ numeral m = (0 :: 'a word)\<close>
+    using True by (simp flip: exp_eq_zero_iff)
+  show ?thesis
+    by (auto simp only: * ** split: option.split
+      dest!: take_bit_num_eq_None_imp [where ?'a = \<open>'a word\<close>] take_bit_num_eq_Some_imp [where ?'a = \<open>'a word\<close>])
+      simp_all
+next
+  case False
+  then show ?thesis
+    by (transfer fixing: m n) (simp add: take_bit_numeral_minus_numeral_int)
+qed
+
+declare take_bit_num_simps [simp] take_bit_num_numeral_simps [simp] take_bit_numeral_numeral [simp]
+  take_bit_numeral_minus_numeral_int [simp] take_bit_numeral_minus_numeral_word [simp]
+
+context semiring_bit_operations \<comment> \<open>TODO move, overwrite\<close>
+begin
+
+lemma of_nat_mask_eq:
+  \<open>of_nat (mask n) = mask n\<close>
+  by (induction n) (simp_all add: mask_Suc_double Bit_Operations.mask_Suc_double of_nat_or_eq)
+
+end
+
+lemma nat_mask_eq: \<comment> \<open>TODO move\<close>
+  \<open>nat (mask n) = mask n\<close>
+  by (simp add: nat_eq_iff of_nat_mask_eq)
+
+lemma (in semiring_bit_operations) unsigned_minus_1_eq_mask: \<comment> \<open>TODO move\<close>
+  \<open>unsigned (- 1 :: 'b::len word) = mask LENGTH('b)\<close>
+  by (transfer fixing: mask) (simp add: take_bit_minus_one_eq_mask nat_mask_eq of_nat_mask_eq)
+
+declare (in semiring_bit_operations) push_bit_of_1 [simp] \<comment> \<open>TODO move\<close>
+
+context ring_bit_operations
+begin
+
+context
+  includes bit_operations_syntax
+begin
+
+lemma slice_eq_mask:
+  \<open>push_bit n (take_bit m (drop_bit n a)) = a AND mask (m + n) AND NOT (mask n)\<close>
+  by (rule bit_eqI) (auto simp add: bit_simps)
+
+end
+
+end
+
+context semiring_bit_operations
+begin
+
+lemma mask_eq_0_iff [simp]: \<comment> \<open>TODO move\<close>
+  \<open>mask n = 0 \<longleftrightarrow> n = 0\<close>
+  by (cases n) (simp_all add: mask_Suc_double or_eq_0_iff)
+
+end
+
+lemma mask_nat_less_exp [simp]: \<comment> \<open>TODO move\<close>
+  \<open>(mask n :: nat) < 2 ^ n\<close>
+  by (simp add: mask_eq_exp_minus_1)
+
+lemma mask_nat_positive_iff [simp]: \<comment> \<open>TODO move\<close>
+  \<open>(0::nat) < mask n \<longleftrightarrow> 0 < n\<close>
+proof (cases \<open>n = 0\<close>)
+  case True
+  then show ?thesis
+    by simp
+next
+  case False
+  then have \<open>0 < n\<close>
+    by simp
+  then have \<open>(0::nat) < mask n\<close>
+    using less_eq_mask [of n] by (rule order_less_le_trans)
+  with \<open>0 < n\<close> show ?thesis
+    by simp
+qed
+
+lemma div_word_self: \<comment> \<open>TODO move\<close>
+  \<open>w div w = 1\<close> if \<open>w \<noteq> 0\<close> for w :: \<open>'a::len word\<close>
+  using that by transfer simp
+
+lemma mod_word_self [simp]:  \<comment> \<open>TODO move\<close>
+  \<open>w mod w = 0\<close> for w :: \<open>'a::len word\<close>
+  apply (cases \<open>w = 0\<close>)
+  apply auto
+  using word_mod_div_equality [of w w] by (simp add: div_word_self)
+
+lemma div_word_less: \<comment> \<open>TODO move\<close>
+  \<open>w div v = 0\<close> if \<open>w < v\<close> for w v :: \<open>'a::len word\<close>
+  using that by transfer simp
+
+lemma mod_word_less: \<comment> \<open>TODO move\<close>
+  \<open>w mod v = w\<close> if \<open>w < v\<close> for w v :: \<open>'a::len word\<close>
+  using word_mod_div_equality [of w v] using that by (simp add: div_word_less)
+
+lemma div_word_one [simp]: \<comment> \<open>TODO move\<close>
+  \<open>1 div w = of_bool (w = 1)\<close> for w :: \<open>'a::len word\<close>
+proof transfer
+  fix k :: int
+  show \<open>take_bit LENGTH('a) (take_bit LENGTH('a) 1 div take_bit LENGTH('a) k) =
+         take_bit LENGTH('a) (of_bool (take_bit LENGTH('a) k = take_bit LENGTH('a) 1))\<close>
+  proof (cases \<open>take_bit LENGTH('a) k > 1\<close>)
+    case False
+    with take_bit_nonnegative [of \<open>LENGTH('a)\<close> k]
+    have \<open>take_bit LENGTH('a) k = 0 \<or> take_bit LENGTH('a) k = 1\<close>
+      by linarith
+    then show ?thesis
+      by auto
+  next
+    case True
+    then show ?thesis
+      by simp
+  qed
+qed
+
+lemma mod_word_one [simp]: \<comment> \<open>TODO move\<close>
+  \<open>1 mod w = 1 - w * of_bool (w = 1)\<close> for w :: \<open>'a::len word\<close>
+  using word_mod_div_equality [of 1 w] by simp
+
+lemma div_word_by_minus_1_eq [simp]: \<comment> \<open>TODO move\<close>
+  \<open>w div - 1 = of_bool (w = - 1)\<close> for w :: \<open>'a::len word\<close>
+  by (auto intro: div_word_less simp add: div_word_self word_order.not_eq_extremum)
+
+lemma mod_word_by_minus_1_eq [simp]: \<comment> \<open>TODO move\<close>
+  \<open>w mod - 1 = w * of_bool (w < - 1)\<close> for w :: \<open>'a::len word\<close>
+  apply (cases \<open>w = - 1\<close>)
+   apply (auto simp add: word_order.not_eq_extremum)
+  using word_mod_div_equality [of w \<open>- 1\<close>] by simp
+
+text \<open>\<close> \<comment> \<open>TODO move\<close>
+
+lemmas less_eq_word_numeral_numeral [simp] =
+  word_le_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_numeral_numeral [simp] =
+  word_less_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_eq_word_minus_numeral_numeral [simp] =
+  word_le_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_minus_numeral_numeral [simp] =
+  word_less_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_eq_word_numeral_minus_numeral [simp] =
+  word_le_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_numeral_minus_numeral [simp] =
+  word_less_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_eq_word_minus_numeral_minus_numeral [simp] =
+  word_le_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_minus_numeral_minus_numeral [simp] =
+  word_less_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_numeral_minus_1 [simp] =
+  word_less_def [of \<open>numeral a\<close> \<open>- 1\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas less_word_minus_numeral_minus_1 [simp] =
+  word_less_def [of \<open>- numeral a\<close> \<open>- 1\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+
+lemmas sless_eq_word_numeral_numeral [simp] =
+  word_sle_eq [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_word_numeral_numeral [simp] =
+  word_sless_alt [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_eq_word_minus_numeral_numeral [simp] =
+  word_sle_eq [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_word_minus_numeral_numeral [simp] =
+  word_sless_alt [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_eq_word_numeral_minus_numeral [simp] =
+  word_sle_eq [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_word_numeral_minus_numeral [simp] =
+  word_sless_alt [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_eq_word_minus_numeral_minus_numeral [simp] =
+  word_sle_eq [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sless_word_minus_numeral_minus_numeral [simp] =
+  word_sless_alt [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+
+lemmas div_word_numeral_numeral [simp] =
+  word_div_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas div_word_minus_numeral_numeral [simp] =
+  word_div_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas div_word_numeral_minus_numeral [simp] =
+  word_div_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas div_word_minus_numeral_minus_numeral [simp] =
+  word_div_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas div_word_minus_1_numeral [simp] =
+  word_div_def [of \<open>- 1\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas div_word_minus_1_minus_numeral [simp] =
+  word_div_def [of \<open>- 1\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+
+lemmas mod_word_numeral_numeral [simp] =
+  word_mod_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas mod_word_minus_numeral_numeral [simp] =
+  word_mod_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas mod_word_numeral_minus_numeral [simp] =
+  word_mod_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas mod_word_minus_numeral_minus_numeral [simp] =
+  word_mod_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas mod_word_minus_1_numeral [simp] =
+  word_mod_def [of \<open>- 1\<close> \<open>numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+lemmas mod_word_minus_1_minus_numeral [simp] =
+  word_mod_def [of \<open>- 1\<close> \<open>- numeral b\<close>, simplified uint_bintrunc uint_bintrunc_neg unsigned_minus_1_eq_mask mask_eq_exp_minus_1]
+  for a b
+
+context ring_bit_operations
+begin
+
+lemmas take_bit_Suc_minus_1 [simp] = take_bit_Suc_1 \<comment> \<open>TODO move\<close>
+
+lemmas take_bit_numeral_minus_1 = take_bit_numeral_1 \<comment> \<open>TODO move\<close>
+
+declare take_bit_minus_one_eq_mask [simp] \<comment> \<open>TODO move, preferred variant\<close>
+
+declare push_bit_minus_one_eq_not_mask [simp] \<comment> \<open>TODO move\<close>
+
+end
+
+lemma bit_minus_numeral_Bit0_Suc_iff [simp]: \<comment> \<open>TODO move\<close>
+  \<open>bit (- numeral (num.Bit0 w) :: int) (Suc n) \<longleftrightarrow> bit (- numeral w :: int) n\<close>
+  by (simp add: bit_Suc)
+
+lemma bit_minus_numeral_Bit1_Suc_iff [simp]: \<comment> \<open>TODO move\<close>
+  \<open>bit (- numeral (num.Bit1 w) :: int) (Suc n) \<longleftrightarrow> \<not> bit (numeral w :: int) n\<close>
+  by (simp add: bit_Suc add_One flip: bit_not_int_iff)
+
+lemma (in ring_bit_operations) push_bit_numeral_minus_1 [simp]: \<comment> \<open>TODO move\<close>
+  \<open>push_bit (numeral n) (- 1) = - (2 ^ numeral n)\<close>
+  by (simp add: push_bit_eq_mult)
+
+lemma take_bit_tightened_less_eq_nat: \<comment> \<open>TODO move\<close>
+  \<open>take_bit m q \<le> take_bit n q\<close> if \<open>m \<le> n\<close> for q :: nat
+proof -
+  have \<open>take_bit m (take_bit n q) \<le> take_bit n q\<close>
+    by (rule take_bit_nat_less_eq_self)
+  with that show ?thesis
+    by simp
+qed
+
+lemma take_bit_tightened_less_eq_int: \<comment> \<open>TODO move\<close>
+  \<open>take_bit m k \<le> take_bit n k\<close> if \<open>m \<le> n\<close> for k :: int
+proof -
+  have \<open>take_bit m (take_bit n k) \<le> take_bit n k\<close>
+    by (simp only: take_bit_int_less_eq_self_iff take_bit_nonnegative)
+  with that show ?thesis
+    by simp
+qed
+
+lemma signed_drop_bit_of_1 [simp]: \<comment> \<open>TODO move\<close>
+  \<open>signed_drop_bit n (1 :: 'a::len word) = of_bool (LENGTH('a) = 1 \<or> n = 0)\<close>
+  apply (transfer fixing: n)
+  apply (cases \<open>LENGTH('a)\<close>)
+   apply (auto simp add: take_bit_signed_take_bit)
+  apply (auto simp add: take_bit_drop_bit gr0_conv_Suc simp flip: take_bit_eq_self_iff_drop_bit_eq_0)
+  done
+
+lemma take_bit_word_beyond_length_eq: \<comment> \<open>TODO move\<close>
+  \<open>take_bit n w = w\<close> if \<open>LENGTH('a) \<le> n\<close> for w :: \<open>'a::len word\<close>
+  using that by transfer simp
+
+
 context
   includes bit_operations_syntax
 begin
 
 \<comment> \<open>problem posed by TPHOLs referee:
       criterion for overflow of addition of signed integers\<close>
 
 lemma sofl_test:
   \<open>sint x + sint y = sint (x + y) \<longleftrightarrow>
     drop_bit (size x - 1) ((x + y XOR x) AND (x + y XOR y)) = 0\<close>
   for x y :: \<open>'a::len word\<close>
 proof -
   obtain n where n: \<open>LENGTH('a) = Suc n\<close>
     by (cases \<open>LENGTH('a)\<close>) simp_all
   have *: \<open>sint x + sint y + 2 ^ Suc n > signed_take_bit n (sint x + sint y) \<Longrightarrow> sint x + sint y \<ge> - (2 ^ n)\<close>
     \<open>signed_take_bit n (sint x + sint y) > sint x + sint y - 2 ^ Suc n \<Longrightarrow> 2 ^ n > sint x + sint y\<close>
     using signed_take_bit_int_greater_eq [of \<open>sint x + sint y\<close> n] signed_take_bit_int_less_eq [of n \<open>sint x + sint y\<close>]
     by (auto intro: ccontr)
   have \<open>sint x + sint y = sint (x + y) \<longleftrightarrow>
     (sint (x + y) < 0 \<longleftrightarrow> sint x < 0) \<or>
     (sint (x + y) < 0 \<longleftrightarrow> sint y < 0)\<close>
     using sint_less [of x] sint_greater_eq [of x] sint_less [of y] sint_greater_eq [of y]
     signed_take_bit_int_eq_self [of \<open>LENGTH('a) - 1\<close> \<open>sint x + sint y\<close>]
     apply (auto simp add: not_less)
        apply (unfold sint_word_ariths)
        apply (subst signed_take_bit_int_eq_self)
          prefer 4
          apply (subst signed_take_bit_int_eq_self)
            prefer 7
            apply (subst signed_take_bit_int_eq_self)
              prefer 10
              apply (subst signed_take_bit_int_eq_self)
                apply (auto simp add: signed_take_bit_int_eq_self signed_take_bit_eq_take_bit_minus take_bit_Suc_from_most n not_less intro!: *)
        apply (smt (z3) take_bit_nonnegative)
       apply (smt (z3) take_bit_int_less_exp)
      apply (smt (z3) take_bit_nonnegative)
     apply (smt (z3) take_bit_int_less_exp)
     done
   then show ?thesis
     apply (simp only: One_nat_def word_size drop_bit_eq_zero_iff_not_bit_last bit_and_iff bit_xor_iff)
     apply (simp add: bit_last_iff)
     done
 qed
 
 lemma unat_power_lower [simp]:
   "unat ((2::'a::len word) ^ n) = 2 ^ n" if "n < LENGTH('a::len)"
   using that by transfer simp
 
 lemma unat_p2: "n < LENGTH('a :: len) \<Longrightarrow> unat (2 ^ n :: 'a word) = 2 ^ n"
   by (fact unat_power_lower)
 
 lemma word_div_lt_eq_0:
   "x < y \<Longrightarrow> x div y = 0" for x :: "'a :: len word"
   by transfer simp
 
 lemma word_div_eq_1_iff: "n div m = 1 \<longleftrightarrow> n \<ge> m \<and> unat n < 2 * unat (m :: 'a :: len word)"
   apply (simp only: word_arith_nat_defs word_le_nat_alt word_of_nat_eq_iff flip: nat_div_eq_Suc_0_iff)
   apply (simp flip: unat_div unsigned_take_bit_eq)
   done
 
 lemma AND_twice [simp]:
   "(w AND m) AND m = w AND m"
   by (fact and.right_idem)
 
 lemma word_combine_masks:
   "w AND m = z \<Longrightarrow> w AND m' = z' \<Longrightarrow> w AND (m OR m') = (z OR z')"
   for w m m' z z' :: \<open>'a::len word\<close>
   by (simp add: bit.conj_disj_distrib)
 
 lemma p2_gt_0:
   "(0 < (2 ^ n :: 'a :: len word)) = (n < LENGTH('a))"
   by (simp add : word_gt_0 not_le)
 
 lemma uint_2p_alt:
   \<open>n < LENGTH('a::len) \<Longrightarrow> uint ((2::'a::len word) ^ n) = 2 ^ n\<close>
   using p2_gt_0 [of n, where ?'a = 'a] by (simp add: uint_2p)
 
 lemma p2_eq_0:
   \<open>(2::'a::len word) ^ n = 0 \<longleftrightarrow> LENGTH('a::len) \<le> n\<close>
   by (fact exp_eq_zero_iff)
 
 lemma p2len:
   \<open>(2 :: 'a word) ^ LENGTH('a::len) = 0\<close>
   by simp
 
 lemma neg_mask_is_div:
   "w AND NOT (mask n) = (w div 2^n) * 2^n"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI)
     (auto simp add: bit_simps simp flip: push_bit_eq_mult drop_bit_eq_div)
 
 lemma neg_mask_is_div':
   "n < size w \<Longrightarrow> w AND NOT (mask n) = ((w div (2 ^ n)) * (2 ^ n))"
   for w :: \<open>'a::len word\<close>
   by (rule neg_mask_is_div)
 
 lemma and_mask_arith:
   "w AND mask n = (w * 2^(size w - n)) div 2^(size w - n)"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI)
     (auto simp add: bit_simps word_size simp flip: push_bit_eq_mult drop_bit_eq_div)
 
 lemma and_mask_arith':
   "0 < n \<Longrightarrow> w AND mask n = (w * 2^(size w - n)) div 2^(size w - n)"
   for w :: \<open>'a::len word\<close>
   by (rule and_mask_arith)
 
 lemma mask_2pm1: "mask n = 2 ^ n - (1 :: 'a::len word)"
   by (fact mask_eq_decr_exp)
 
 lemma add_mask_fold:
   "x + 2 ^ n - 1 = x + mask n"
   for x :: \<open>'a::len word\<close>
   by (simp add: mask_eq_decr_exp)
 
 lemma word_and_mask_le_2pm1: "w AND mask n \<le> 2 ^ n - 1"
   for w :: \<open>'a::len word\<close>
   by (simp add: mask_2pm1[symmetric] word_and_le1)
 
 lemma is_aligned_AND_less_0:
   "u AND mask n = 0 \<Longrightarrow> v < 2^n \<Longrightarrow> u AND v = 0"
   for u v :: \<open>'a::len word\<close>
   apply (drule less_mask_eq)
   apply (simp flip: take_bit_eq_mask)
   apply (simp add: bit_eq_iff)
   apply (auto simp add: bit_simps)
   done
 
 lemma and_mask_eq_iff_le_mask:
   \<open>w AND mask n = w \<longleftrightarrow> w \<le> mask n\<close>
   for w :: \<open>'a::len word\<close>
   apply (simp flip: take_bit_eq_mask)
   apply (cases \<open>n \<ge> LENGTH('a)\<close>; transfer)
    apply (simp_all add: not_le min_def)
    apply (simp_all add: mask_eq_exp_minus_1)
   apply auto
    apply (metis take_bit_int_less_exp)
   apply (metis min_def nat_less_le take_bit_int_eq_self_iff take_bit_take_bit)
   done
 
 lemma less_eq_mask_iff_take_bit_eq_self:
   \<open>w \<le> mask n \<longleftrightarrow> take_bit n w = w\<close>
   for w :: \<open>'a::len word\<close>
   by (simp add: and_mask_eq_iff_le_mask take_bit_eq_mask)
 
 lemma NOT_eq:
   "NOT (x :: 'a :: len word) = - x - 1"
   apply (cut_tac x = "x" in word_add_not)
   apply (drule add.commute [THEN trans])
   apply (drule eq_diff_eq [THEN iffD2])
   by simp
 
 lemma NOT_mask: "NOT (mask n :: 'a::len word) = - (2 ^ n)"
   by (simp add : NOT_eq mask_2pm1)
 
 lemma le_m1_iff_lt: "(x > (0 :: 'a :: len word)) = ((y \<le> x - 1) = (y < x))"
   by uint_arith
 
 lemma gt0_iff_gem1:
   \<open>0 < x \<longleftrightarrow> x - 1 < x\<close>
   for x :: \<open>'a::len word\<close>
   by (metis add.right_neutral diff_add_cancel less_irrefl measure_unat unat_arith_simps(2) word_neq_0_conv word_sub_less_iff)
 
 lemma power_2_ge_iff:
   \<open>2 ^ n - (1 :: 'a::len word) < 2 ^ n \<longleftrightarrow> n < LENGTH('a)\<close>
   using gt0_iff_gem1 p2_gt_0 by blast
 
 lemma le_mask_iff_lt_2n:
   "n < len_of TYPE ('a) = (((w :: 'a :: len word) \<le> mask n) = (w < 2 ^ n))"
   unfolding mask_2pm1 by (rule trans [OF p2_gt_0 [THEN sym] le_m1_iff_lt])
 
 lemma mask_lt_2pn:
   \<open>n < LENGTH('a) \<Longrightarrow> mask n < (2 :: 'a::len word) ^ n\<close>
   by (simp add: mask_eq_exp_minus_1 power_2_ge_iff)
 
 lemma word_unat_power:
   "(2 :: 'a :: len word) ^ n = of_nat (2 ^ n)"
   by simp
 
 lemma of_nat_mono_maybe:
   assumes xlt: "x < 2 ^ len_of TYPE ('a)"
   shows   "y < x \<Longrightarrow> of_nat y < (of_nat x :: 'a :: len word)"
   apply (subst word_less_nat_alt)
   apply (subst unat_of_nat)+
   apply (subst mod_less)
    apply (erule order_less_trans [OF _ xlt])
   apply (subst mod_less [OF xlt])
   apply assumption
   done
 
 lemma word_and_max_word:
   fixes a::"'a::len word"
   shows "x = - 1 \<Longrightarrow> a AND x = a"
   by simp
 
 lemma word_and_full_mask_simp:
   \<open>x AND mask LENGTH('a) = x\<close> for x :: \<open>'a::len word\<close>
   by (simp add: bit_eq_iff bit_simps)
 
 lemma of_int_uint:
   "of_int (uint x) = x"
   by (fact word_of_int_uint)
 
 corollary word_plus_and_or_coroll:
   "x AND y = 0 \<Longrightarrow> x + y = x OR y"
   for x y :: \<open>'a::len word\<close>
   using word_plus_and_or[where x=x and y=y]
   by simp
 
 corollary word_plus_and_or_coroll2:
   "(x AND w) + (x AND NOT w) = x"
   for x w :: \<open>'a::len word\<close>
   apply (subst disjunctive_add)
    apply (simp add: bit_simps)
   apply (simp flip: bit.conj_disj_distrib)
   done
 
-lemma nat_mask_eq:
-  \<open>nat (mask n) = mask n\<close>
-  by (simp add: nat_eq_iff of_nat_mask_eq)
-
 lemma unat_mask_eq:
   \<open>unat (mask n :: 'a::len word) = mask (min LENGTH('a) n)\<close>
   by transfer (simp add: nat_mask_eq)
 
 lemma word_plus_mono_left:
   fixes x :: "'a :: len word"
   shows "\<lbrakk>y \<le> z; x \<le> x + z\<rbrakk> \<Longrightarrow> y + x \<le> z + x"
   by unat_arith
 
 lemma less_Suc_unat_less_bound:
   "n < Suc (unat (x :: 'a :: len word)) \<Longrightarrow> n < 2 ^ LENGTH('a)"
   by (auto elim!: order_less_le_trans intro: Suc_leI)
 
 lemma up_ucast_inj:
   "\<lbrakk> ucast x = (ucast y::'b::len word); LENGTH('a) \<le> len_of TYPE ('b) \<rbrakk> \<Longrightarrow> x = (y::'a::len word)"
   by transfer (simp add: min_def split: if_splits)
 
 lemmas ucast_up_inj = up_ucast_inj
 
 lemma up_ucast_inj_eq:
   "LENGTH('a) \<le> len_of TYPE ('b) \<Longrightarrow> (ucast x = (ucast y::'b::len word)) = (x = (y::'a::len word))"
   by (fastforce dest: up_ucast_inj)
 
 lemma no_plus_overflow_neg:
   "(x :: 'a :: len word) < -y \<Longrightarrow> x \<le> x + y"
   by (metis diff_minus_eq_add less_imp_le sub_wrap_lt)
 
 lemma ucast_ucast_eq:
   "\<lbrakk> ucast x = (ucast (ucast y::'a word)::'c::len word); LENGTH('a) \<le> LENGTH('b);
      LENGTH('b) \<le> LENGTH('c) \<rbrakk> \<Longrightarrow>
    x = ucast y" for x :: "'a::len word" and y :: "'b::len word"
   apply transfer
   apply (cases \<open>LENGTH('c) = LENGTH('a)\<close>)
    apply (auto simp add: min_def)
   done
 
 lemma ucast_0_I:
   "x = 0 \<Longrightarrow> ucast x = 0"
   by simp
 
 lemma word_add_offset_less:
   fixes x :: "'a :: len word"
   assumes yv: "y < 2 ^ n"
   and     xv: "x < 2 ^ m"
   and     mnv: "sz < LENGTH('a :: len)"
   and    xv': "x < 2 ^ (LENGTH('a :: len) - n)"
   and     mn: "sz = m + n"
   shows   "x * 2 ^ n + y < 2 ^ sz"
 proof (subst mn)
   from mnv mn have nv: "n < LENGTH('a)" and mv: "m < LENGTH('a)"  by auto
 
   have uy: "unat y < 2 ^ n"
     by (rule order_less_le_trans [OF unat_mono [OF yv] order_eq_refl],
         rule unat_power_lower[OF nv])
 
   have ux: "unat x < 2 ^ m"
     by (rule order_less_le_trans [OF unat_mono [OF xv] order_eq_refl],
         rule unat_power_lower[OF mv])
 
   then show "x * 2 ^ n + y < 2 ^ (m + n)" using ux uy nv mnv xv'
     apply (subst word_less_nat_alt)
     apply (subst unat_word_ariths)+
     apply (subst mod_less)
      apply simp
      apply (subst mult.commute)
      apply (rule nat_less_power_trans [OF _ order_less_imp_le [OF nv]])
      apply (rule order_less_le_trans [OF unat_mono [OF xv']])
      apply (cases "n = 0"; simp)
     apply (subst unat_power_lower[OF nv])
     apply (subst mod_less)
      apply (erule order_less_le_trans [OF nat_add_offset_less], assumption)
       apply (rule mn)
      apply simp
     apply (simp add: mn mnv)
     apply (erule nat_add_offset_less; simp)
     done
 qed
 
 lemma word_less_power_trans:
   fixes n :: "'a :: len word"
   assumes nv: "n < 2 ^ (m - k)"
   and     kv: "k \<le> m"
   and     mv: "m < len_of TYPE ('a)"
   shows "2 ^ k * n < 2 ^ m"
   using nv kv mv
   apply -
   apply (subst word_less_nat_alt)
   apply (subst unat_word_ariths)
   apply (subst mod_less)
    apply simp
    apply (rule nat_less_power_trans)
     apply (erule order_less_trans [OF unat_mono])
     apply simp
    apply simp
   apply simp
   apply (rule nat_less_power_trans)
    apply (subst unat_power_lower[where 'a = 'a, symmetric])
     apply simp
    apply (erule unat_mono)
   apply simp
   done
 
 lemma  word_less_power_trans2:
   fixes n :: "'a::len word"
   shows "\<lbrakk>n < 2 ^ (m - k); k \<le> m; m < LENGTH('a)\<rbrakk> \<Longrightarrow> n * 2 ^ k < 2 ^ m"
   by (subst field_simps, rule word_less_power_trans)
 
 lemma Suc_unat_diff_1:
   fixes x :: "'a :: len word"
   assumes lt: "1 \<le> x"
   shows "Suc (unat (x - 1)) = unat x"
 proof -
   have "0 < unat x"
     by (rule order_less_le_trans [where y = 1], simp, subst unat_1 [symmetric],
         rule iffD1 [OF word_le_nat_alt lt])
 
   then show ?thesis
     by ((subst unat_sub [OF lt])+, simp only:  unat_1)
 qed
 
 lemma word_eq_unatI:
   \<open>v = w\<close> if \<open>unat v = unat w\<close>
   using that by transfer (simp add: nat_eq_iff)
 
 lemma word_div_sub:
   fixes x :: "'a :: len word"
   assumes yx: "y \<le> x"
   and     y0: "0 < y"
   shows "(x - y) div y = x div y - 1"
   apply (rule word_eq_unatI)
   apply (subst unat_div)
   apply (subst unat_sub [OF yx])
   apply (subst unat_sub)
    apply (subst word_le_nat_alt)
    apply (subst unat_div)
    apply (subst le_div_geq)
      apply (rule order_le_less_trans [OF _ unat_mono [OF y0]])
      apply simp
     apply (subst word_le_nat_alt [symmetric], rule yx)
    apply simp
   apply (subst unat_div)
   apply (subst le_div_geq [OF _ iffD1 [OF word_le_nat_alt yx]])
    apply (rule order_le_less_trans [OF _ unat_mono [OF y0]])
    apply simp
   apply simp
   done
 
 lemma word_mult_less_mono1:
   fixes i :: "'a :: len word"
   assumes ij: "i < j"
   and    knz: "0 < k"
   and    ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows  "i * k < j * k"
 proof -
   from ij ujk knz have jk: "unat i * unat k < 2 ^ len_of TYPE ('a)"
     by (auto intro: order_less_subst2 simp: word_less_nat_alt elim: mult_less_mono1)
 
   then show ?thesis using ujk knz ij
     by (auto simp: word_less_nat_alt iffD1 [OF unat_mult_lem])
 qed
 
 lemma word_mult_less_dest:
   fixes i :: "'a :: len word"
   assumes ij: "i * k < j * k"
   and    uik: "unat i * unat k < 2 ^ len_of TYPE ('a)"
   and    ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows  "i < j"
   using uik ujk ij
   by (auto simp: word_less_nat_alt iffD1 [OF unat_mult_lem] elim: mult_less_mono1)
 
 lemma word_mult_less_cancel:
   fixes k :: "'a :: len word"
   assumes knz: "0 < k"
   and    uik: "unat i * unat k < 2 ^ len_of TYPE ('a)"
   and    ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows "(i * k < j * k) = (i < j)"
   by (rule iffI [OF word_mult_less_dest [OF _ uik ujk] word_mult_less_mono1 [OF _ knz ujk]])
 
 lemma Suc_div_unat_helper:
   assumes szv: "sz < LENGTH('a :: len)"
   and   usszv: "us \<le> sz"
   shows "2 ^ (sz - us) = Suc (unat (((2::'a :: len word) ^ sz - 1) div 2 ^ us))"
 proof -
   note usv = order_le_less_trans [OF usszv szv]
 
   from usszv obtain q where qv: "sz = us + q" by (auto simp: le_iff_add)
 
   have "Suc (unat (((2:: 'a word) ^ sz - 1) div 2 ^ us)) =
     (2 ^ us + unat ((2:: 'a word) ^ sz - 1)) div 2 ^ us"
     apply (subst unat_div unat_power_lower[OF usv])+
     apply (subst div_add_self1, simp+)
     done
 
   also have "\<dots> = ((2 ^ us - 1) + 2 ^ sz) div 2 ^ us" using szv
     by (simp add: unat_minus_one)
 
   also have "\<dots> = 2 ^ q + ((2 ^ us - 1) div 2 ^ us)"
     apply (subst qv)
     apply (subst power_add)
     apply (subst div_mult_self2; simp)
     done
 
   also have "\<dots> = 2 ^ (sz - us)" using qv by simp
 
   finally show ?thesis ..
 qed
 
 lemma enum_word_nth_eq:
   \<open>(Enum.enum :: 'a::len word list) ! n = word_of_nat n\<close>
     if \<open>n < 2 ^ LENGTH('a)\<close>
     for n
   using that by (simp add: enum_word_def)
 
 lemma length_enum_word_eq:
   \<open>length (Enum.enum :: 'a::len word list) = 2 ^ LENGTH('a)\<close>
   by (simp add: enum_word_def)
 
 lemma unat_lt2p [iff]:
   \<open>unat x < 2 ^ LENGTH('a)\<close> for x :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma of_nat_unat [simp]:
   "of_nat \<circ> unat = id"
   by (rule ext, simp)
 
 lemma Suc_unat_minus_one [simp]:
   "x \<noteq> 0 \<Longrightarrow> Suc (unat (x - 1)) = unat x"
   by (metis Suc_diff_1 unat_gt_0 unat_minus_one)
 
 lemma word_add_le_dest:
   fixes i :: "'a :: len word"
   assumes le: "i + k \<le> j + k"
   and    uik: "unat i + unat k < 2 ^ len_of TYPE ('a)"
   and    ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "i \<le> j"
   using uik ujk le
   by (auto simp: word_le_nat_alt iffD1 [OF unat_add_lem] elim: add_le_mono1)
 
 lemma word_add_le_mono1:
   fixes i :: "'a :: len word"
   assumes ij: "i \<le> j"
   and    ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "i + k \<le> j + k"
 proof -
   from ij ujk have jk: "unat i + unat k < 2 ^ len_of TYPE ('a)"
     by (auto elim: order_le_less_subst2 simp: word_le_nat_alt elim: add_le_mono1)
 
   then show ?thesis using ujk ij
     by (auto simp: word_le_nat_alt iffD1 [OF unat_add_lem])
 qed
 
 lemma word_add_le_mono2:
   fixes i :: "'a :: len word"
   shows "\<lbrakk>i \<le> j; unat j + unat k < 2 ^ LENGTH('a)\<rbrakk> \<Longrightarrow> k + i \<le> k + j"
   by (subst field_simps, subst field_simps, erule (1) word_add_le_mono1)
 
 lemma word_add_le_iff:
   fixes i :: "'a :: len word"
   assumes uik: "unat i + unat k < 2 ^ len_of TYPE ('a)"
   and     ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "(i + k \<le> j + k) = (i \<le> j)"
 proof
   assume "i \<le> j"
   show "i + k \<le> j + k" by (rule word_add_le_mono1) fact+
 next
   assume "i + k \<le> j + k"
   show "i \<le> j" by (rule word_add_le_dest) fact+
 qed
 
 lemma word_add_less_mono1:
   fixes i :: "'a :: len word"
   assumes ij: "i < j"
   and    ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "i + k < j + k"
 proof -
   from ij ujk have jk: "unat i + unat k < 2 ^ len_of TYPE ('a)"
     by (auto elim: order_le_less_subst2 simp: word_less_nat_alt elim: add_less_mono1)
 
   then show ?thesis using ujk ij
     by (auto simp: word_less_nat_alt iffD1 [OF unat_add_lem])
 qed
 
 lemma word_add_less_dest:
   fixes i :: "'a :: len word"
   assumes le: "i + k < j + k"
   and    uik: "unat i + unat k < 2 ^ len_of TYPE ('a)"
   and    ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "i < j"
   using uik ujk le
   by (auto simp: word_less_nat_alt iffD1 [OF unat_add_lem] elim: add_less_mono1)
 
 lemma word_add_less_iff:
   fixes i :: "'a :: len word"
   assumes uik: "unat i + unat k < 2 ^ len_of TYPE ('a)"
   and     ujk: "unat j + unat k < 2 ^ len_of TYPE ('a)"
   shows  "(i + k < j + k) = (i < j)"
 proof
   assume "i < j"
   show "i + k < j + k" by (rule word_add_less_mono1) fact+
 next
   assume "i + k < j + k"
   show "i < j" by (rule word_add_less_dest) fact+
 qed
 
 lemma word_mult_less_iff:
   fixes i :: "'a :: len word"
   assumes knz: "0 < k"
   and     uik: "unat i * unat k < 2 ^ len_of TYPE ('a)"
   and     ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows  "(i * k < j * k) = (i < j)"
   using assms by (rule word_mult_less_cancel)
 
 lemma word_le_imp_diff_le:
   fixes n :: "'a::len word"
   shows "\<lbrakk>k \<le> n; n \<le> m\<rbrakk> \<Longrightarrow> n - k \<le> m"
   by (auto simp: unat_sub word_le_nat_alt)
 
 lemma word_less_imp_diff_less:
   fixes n :: "'a::len word"
   shows "\<lbrakk>k \<le> n; n < m\<rbrakk> \<Longrightarrow> n - k < m"
   by (clarsimp simp: unat_sub word_less_nat_alt
              intro!: less_imp_diff_less)
 
 lemma word_mult_le_mono1:
   fixes i :: "'a :: len word"
   assumes ij: "i \<le> j"
   and    knz: "0 < k"
   and    ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows  "i * k \<le> j * k"
 proof -
   from ij ujk knz have jk: "unat i * unat k < 2 ^ len_of TYPE ('a)"
     by (auto elim: order_le_less_subst2 simp: word_le_nat_alt elim: mult_le_mono1)
 
   then show ?thesis using ujk knz ij
     by (auto simp: word_le_nat_alt iffD1 [OF unat_mult_lem])
 qed
 
 lemma word_mult_le_iff:
   fixes i :: "'a :: len word"
   assumes knz: "0 < k"
   and     uik: "unat i * unat k < 2 ^ len_of TYPE ('a)"
   and     ujk: "unat j * unat k < 2 ^ len_of TYPE ('a)"
   shows  "(i * k \<le> j * k) = (i \<le> j)"
 proof
   assume "i \<le> j"
   show "i * k \<le> j * k" by (rule word_mult_le_mono1) fact+
 next
   assume p: "i * k \<le> j * k"
 
   have "0 < unat k" using knz by (simp add: word_less_nat_alt)
   then show "i \<le> j" using p
     by (clarsimp simp: word_le_nat_alt iffD1 [OF unat_mult_lem uik]
       iffD1 [OF unat_mult_lem ujk])
 qed
 
 lemma word_diff_less:
   fixes n :: "'a :: len word"
   shows "\<lbrakk>0 < n; 0 < m; n \<le> m\<rbrakk> \<Longrightarrow> m - n < m"
   apply (subst word_less_nat_alt)
   apply (subst unat_sub)
    apply assumption
   apply (rule diff_less)
    apply (simp_all add: word_less_nat_alt)
   done
 
 lemma word_add_increasing:
   fixes x :: "'a :: len word"
   shows "\<lbrakk> p + w \<le> x; p \<le> p + w \<rbrakk> \<Longrightarrow> p \<le> x"
   by unat_arith
 
 lemma word_random:
   fixes x :: "'a :: len word"
   shows "\<lbrakk> p \<le> p + x'; x \<le> x' \<rbrakk> \<Longrightarrow> p \<le> p + x"
   by unat_arith
 
 lemma word_sub_mono:
   "\<lbrakk> a \<le> c; d \<le> b; a - b \<le> a; c - d \<le> c \<rbrakk>
     \<Longrightarrow> (a - b) \<le> (c - d :: 'a :: len word)"
   by unat_arith
 
 lemma power_not_zero:
   "n < LENGTH('a::len) \<Longrightarrow> (2 :: 'a word) ^ n \<noteq> 0"
   by (metis p2_gt_0 word_neq_0_conv)
 
 lemma word_gt_a_gt_0:
   "a < n \<Longrightarrow> (0 :: 'a::len word) < n"
   apply (case_tac "n = 0")
    apply clarsimp
   apply (clarsimp simp: word_neq_0_conv)
   done
 
 lemma word_power_less_1 [simp]:
   "sz < LENGTH('a::len) \<Longrightarrow> (2::'a word) ^ sz - 1 < 2 ^ sz"
   apply (simp add: word_less_nat_alt)
   apply (subst unat_minus_one)
   apply simp_all
   done
 
 lemma word_sub_1_le:
   "x \<noteq> 0 \<Longrightarrow> x - 1 \<le> (x :: ('a :: len) word)"
   apply (subst no_ulen_sub)
   apply simp
   apply (cases "uint x = 0")
    apply (simp add: uint_0_iff)
   apply (insert uint_ge_0[where x=x])
   apply arith
   done
 
 lemma push_bit_word_eq_nonzero:
   \<open>push_bit n w \<noteq> 0\<close> if \<open>w < 2 ^ m\<close> \<open>m + n < LENGTH('a)\<close> \<open>w \<noteq> 0\<close>
     for w :: \<open>'a::len word\<close>
   using that
   apply (simp only: word_neq_0_conv word_less_nat_alt
                     mod_0 unat_word_ariths
                     unat_power_lower word_le_nat_alt)
   apply (metis add_diff_cancel_right' gr0I gr_implies_not0 less_or_eq_imp_le min_def push_bit_eq_0_iff take_bit_nat_eq_self_iff take_bit_push_bit take_bit_take_bit unsigned_push_bit_eq)
   done
 
 lemma unat_less_power:
   fixes k :: "'a::len word"
   assumes szv: "sz < LENGTH('a)"
   and     kv:  "k < 2 ^ sz"
   shows   "unat k < 2 ^ sz"
   using szv unat_mono [OF kv] by simp
 
 lemma unat_mult_power_lem:
   assumes kv: "k < 2 ^ (LENGTH('a::len) - sz)"
   shows "unat (2 ^ sz * of_nat k :: (('a::len) word)) = 2 ^ sz * k"
 proof (cases \<open>sz < LENGTH('a)\<close>)
   case True
   with assms show ?thesis
     by (simp add: unat_word_ariths take_bit_eq_mod mod_simps unsigned_of_nat)
       (simp add: take_bit_nat_eq_self_iff nat_less_power_trans flip: take_bit_eq_mod)
 next
   case False
   with assms show ?thesis
     by simp
 qed
 
 lemma word_plus_mcs_4:
   "\<lbrakk>v + x \<le> w + x; x \<le> v + x\<rbrakk> \<Longrightarrow> v \<le> (w::'a::len word)"
   by uint_arith
 
 lemma word_plus_mcs_3:
   "\<lbrakk>v \<le> w; x \<le> w + x\<rbrakk> \<Longrightarrow> v + x \<le> w + (x::'a::len word)"
   by unat_arith
 
 lemma word_le_minus_one_leq:
   "x < y \<Longrightarrow> x \<le> y - 1" for x :: "'a :: len word"
   by transfer (metis le_less_trans less_irrefl take_bit_decr_eq take_bit_nonnegative zle_diff1_eq)
 
 lemma word_less_sub_le[simp]:
   fixes x :: "'a :: len word"
   assumes nv: "n < LENGTH('a)"
   shows "(x \<le> 2 ^ n - 1) = (x < 2 ^ n)"
   using le_less_trans word_le_minus_one_leq nv power_2_ge_iff by blast
 
 lemma unat_of_nat_len:
   "x < 2 ^ LENGTH('a) \<Longrightarrow> unat (of_nat x :: 'a::len word) = x"
   by (simp add: unsigned_of_nat take_bit_nat_eq_self_iff)
 
 lemma unat_of_nat_eq:
   "x < 2 ^ LENGTH('a) \<Longrightarrow> unat (of_nat x ::'a::len word) = x"
   by (rule unat_of_nat_len)
 
 lemma unat_eq_of_nat:
   "n < 2 ^ LENGTH('a) \<Longrightarrow> (unat (x :: 'a::len word) = n) = (x = of_nat n)"
   by transfer
     (auto simp add: take_bit_of_nat nat_eq_iff take_bit_nat_eq_self_iff intro: sym)
 
 lemma alignUp_div_helper:
   fixes a :: "'a::len word"
   assumes kv: "k < 2 ^ (LENGTH('a) - n)"
   and     xk: "x = 2 ^ n * of_nat k"
   and    le: "a \<le> x"
   and    sz: "n < LENGTH('a)"
   and   anz: "a mod 2 ^ n \<noteq> 0"
   shows "a div 2 ^ n < of_nat k"
 proof -
   have kn: "unat (of_nat k :: 'a word) * unat ((2::'a word) ^ n) < 2 ^ LENGTH('a)"
     using xk kv sz
     apply (subst unat_of_nat_eq)
      apply (erule order_less_le_trans)
      apply simp
     apply (subst unat_power_lower, simp)
     apply (subst mult.commute)
     apply (rule nat_less_power_trans)
      apply simp
     apply simp
     done
 
   have "unat a div 2 ^ n * 2 ^ n \<noteq> unat a"
   proof -
     have "unat a = unat a div 2 ^ n * 2 ^ n + unat a mod 2 ^ n"
       by (simp add: div_mult_mod_eq)
     also have "\<dots> \<noteq> unat a div 2 ^ n * 2 ^ n" using sz anz
       by (simp add: unat_arith_simps)
     finally show ?thesis ..
   qed
 
   then have "a div 2 ^ n * 2 ^ n < a" using sz anz
     apply (subst word_less_nat_alt)
     apply (subst unat_word_ariths)
     apply (subst unat_div)
     apply simp
     apply (rule order_le_less_trans [OF mod_less_eq_dividend])
     apply (erule order_le_neq_trans [OF div_mult_le])
     done
 
   also from xk le have "\<dots> \<le> of_nat k * 2 ^ n" by (simp add: field_simps)
   finally show ?thesis using sz kv
     apply -
     apply (erule word_mult_less_dest [OF _ _ kn])
     apply (simp add: unat_div)
     apply (rule order_le_less_trans [OF div_mult_le])
     apply (rule unat_lt2p)
     done
 qed
 
 lemma mask_out_sub_mask:
   "(x AND NOT (mask n)) = x - (x AND (mask n))"
   for x :: \<open>'a::len word\<close>
   by (simp add: field_simps word_plus_and_or_coroll2)
 
 lemma subtract_mask:
   "p - (p AND mask n) = (p AND NOT (mask n))"
   "p - (p AND NOT (mask n)) = (p AND mask n)"
   for p :: \<open>'a::len word\<close>
   by (simp add: field_simps word_plus_and_or_coroll2)+
 
 lemma take_bit_word_eq_self_iff:
   \<open>take_bit n w = w \<longleftrightarrow> n \<ge> LENGTH('a) \<or> w < 2 ^ n\<close>
   for w :: \<open>'a::len word\<close>
   using take_bit_int_eq_self_iff [of n \<open>take_bit LENGTH('a) (uint w)\<close>]
   by (transfer fixing: n) auto
 
 lemma word_power_increasing:
   assumes x: "2 ^ x < (2 ^ y::'a::len word)" "x < LENGTH('a::len)" "y < LENGTH('a::len)"
   shows "x < y" using x
   using assms by transfer simp
 
 lemma mask_twice:
   "(x AND mask n) AND mask m = x AND mask (min m n)"
   for x :: \<open>'a::len word\<close>
   by (simp flip: take_bit_eq_mask)
 
 lemma plus_one_helper[elim!]:
   "x < n + (1 :: 'a :: len word) \<Longrightarrow> x \<le> n"
   apply (simp add: word_less_nat_alt word_le_nat_alt field_simps)
   apply (case_tac "1 + n = 0")
    apply simp_all
   apply (subst(asm) unatSuc, assumption)
   apply arith
   done
 
 lemma plus_one_helper2:
   "\<lbrakk> x \<le> n; n + 1 \<noteq> 0 \<rbrakk> \<Longrightarrow> x < n + (1 :: 'a :: len word)"
   by (simp add: word_less_nat_alt word_le_nat_alt field_simps
                 unatSuc)
 
 lemma less_x_plus_1:
   fixes x :: "'a :: len word" shows
   "x \<noteq> - 1 \<Longrightarrow> (y < (x + 1)) = (y < x \<or> y = x)"
   apply (rule iffI)
    apply (rule disjCI)
    apply (drule plus_one_helper)
    apply simp
   apply (subgoal_tac "x < x + 1")
    apply (erule disjE, simp_all)
   apply (rule plus_one_helper2 [OF order_refl])
   apply (rule notI, drule max_word_wrap)
   apply simp
   done
 
 lemma word_Suc_leq:
   fixes k::"'a::len word" shows "k \<noteq> - 1 \<Longrightarrow> x < k + 1 \<longleftrightarrow> x \<le> k"
   using less_x_plus_1 word_le_less_eq by auto
 
 lemma word_Suc_le:
    fixes k::"'a::len word" shows "x \<noteq> - 1 \<Longrightarrow> x + 1 \<le> k \<longleftrightarrow> x < k"
   by (meson not_less word_Suc_leq)
 
 lemma word_lessThan_Suc_atMost:
   \<open>{..< k + 1} = {..k}\<close> if \<open>k \<noteq> - 1\<close> for k :: \<open>'a::len word\<close>
   using that by (simp add: lessThan_def atMost_def word_Suc_leq)
 
 lemma word_atLeastLessThan_Suc_atLeastAtMost:
   \<open>{l ..< u + 1} = {l..u}\<close> if \<open>u \<noteq> - 1\<close> for l :: \<open>'a::len word\<close>
   using that by (simp add: atLeastAtMost_def atLeastLessThan_def word_lessThan_Suc_atMost)
 
 lemma word_atLeastAtMost_Suc_greaterThanAtMost:
   \<open>{m<..u} = {m + 1..u}\<close> if \<open>m \<noteq> - 1\<close> for m :: \<open>'a::len word\<close>
   using that by (simp add: greaterThanAtMost_def greaterThan_def atLeastAtMost_def atLeast_def word_Suc_le)
 
 lemma word_atLeastLessThan_Suc_atLeastAtMost_union:
   fixes l::"'a::len word"
   assumes "m \<noteq> - 1" and "l \<le> m" and "m \<le> u"
   shows "{l..m} \<union> {m+1..u} = {l..u}"
   proof -
   from ivl_disj_un_two(8)[OF assms(2) assms(3)] have "{l..u} = {l..m} \<union> {m<..u}" by blast
   with assms show ?thesis by(simp add: word_atLeastAtMost_Suc_greaterThanAtMost)
   qed
 
 lemma max_word_less_eq_iff [simp]:
   \<open>- 1 \<le> w \<longleftrightarrow> w = - 1\<close> for w :: \<open>'a::len word\<close>
   by (fact word_order.extremum_unique)
 
 lemma word_or_zero:
   "(a OR b = 0) = (a = 0 \<and> b = 0)"
   for a b :: \<open>'a::len word\<close>
   by (fact or_eq_0_iff)
 
 lemma word_2p_mult_inc:
   assumes x: "2 * 2 ^ n < (2::'a::len word) * 2 ^ m"
   assumes suc_n: "Suc n < LENGTH('a::len)"
   shows "2^n < (2::'a::len word)^m"
   by (smt suc_n le_less_trans lessI nat_less_le nat_mult_less_cancel_disj p2_gt_0
           power_Suc power_Suc unat_power_lower word_less_nat_alt x)
 
 lemma power_overflow:
   "n \<ge> LENGTH('a) \<Longrightarrow> 2 ^ n = (0 :: 'a::len word)"
   by simp
 
 lemmas extra_sle_sless_unfolds [simp] =
     word_sle_eq[where a=0 and b=1]
     word_sle_eq[where a=0 and b="numeral n"]
     word_sle_eq[where a=1 and b=0]
     word_sle_eq[where a=1 and b="numeral n"]
     word_sle_eq[where a="numeral n" and b=0]
     word_sle_eq[where a="numeral n" and b=1]
     word_sless_alt[where a=0 and b=1]
     word_sless_alt[where a=0 and b="numeral n"]
     word_sless_alt[where a=1 and b=0]
     word_sless_alt[where a=1 and b="numeral n"]
     word_sless_alt[where a="numeral n" and b=0]
     word_sless_alt[where a="numeral n" and b=1]
   for n
 
 lemma word_sint_1:
   "sint (1::'a::len word) = (if LENGTH('a) = 1 then -1 else 1)"
   by (fact signed_1)
 
 lemma ucast_of_nat:
   "is_down (ucast :: 'a :: len word \<Rightarrow> 'b :: len word)
     \<Longrightarrow> ucast (of_nat n :: 'a word) = (of_nat n :: 'b word)"
   by transfer simp
 
 lemma scast_1':
   "(scast (1::'a::len word) :: 'b::len word) =
    (word_of_int (signed_take_bit (LENGTH('a::len) - Suc 0) (1::int)))"
   by transfer simp
 
 lemma scast_1:
   "(scast (1::'a::len word) :: 'b::len word) = (if LENGTH('a) = 1 then -1 else 1)"
   by (fact signed_1)
 
 lemma unat_minus_one_word:
   "unat (-1 :: 'a :: len word) = 2 ^ LENGTH('a) - 1"
-  apply (simp only: flip: mask_eq_exp_minus_1)
-  apply transfer
-  apply (simp add: take_bit_minus_one_eq_mask nat_mask_eq)
-  done
+  by (simp add: mask_eq_exp_minus_1 unsigned_minus_1_eq_mask)
 
 lemmas word_diff_ls'' = word_diff_ls [where xa=x and x=x for x]
 lemmas word_diff_ls' = word_diff_ls'' [simplified]
 
 lemmas word_l_diffs' = word_l_diffs [where xa=x and x=x for x]
 lemmas word_l_diffs = word_l_diffs' [simplified]
 
 lemma two_power_increasing:
   "\<lbrakk> n \<le> m; m < LENGTH('a) \<rbrakk> \<Longrightarrow> (2 :: 'a :: len word) ^ n \<le> 2 ^ m"
   by (simp add: word_le_nat_alt)
 
 lemma word_leq_le_minus_one:
   "\<lbrakk> x \<le> y; x \<noteq> 0 \<rbrakk> \<Longrightarrow> x - 1 < (y :: 'a :: len word)"
   apply (simp add: word_less_nat_alt word_le_nat_alt)
   apply (subst unat_minus_one)
    apply assumption
   apply (cases "unat x")
    apply (simp add: unat_eq_zero)
   apply arith
   done
 
 lemma neg_mask_combine:
   "NOT(mask a) AND NOT(mask b) = NOT(mask (max a b) :: 'a::len word)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma neg_mask_twice:
   "x AND NOT(mask n) AND NOT(mask m) = x AND NOT(mask (max n m))"
   for x :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma multiple_mask_trivia:
   "n \<ge> m \<Longrightarrow> (x AND NOT(mask n)) + (x AND mask n AND NOT(mask m)) = x AND NOT(mask m)"
   for x :: \<open>'a::len word\<close>
   apply (rule trans[rotated], rule_tac w="mask n" in word_plus_and_or_coroll2)
   apply (simp add: word_bw_assocs word_bw_comms word_bw_lcs neg_mask_twice
                    max_absorb2)
   done
 
 lemma word_of_nat_less:
   "\<lbrakk> n < unat x \<rbrakk> \<Longrightarrow> of_nat n < x"
   apply (simp add: word_less_nat_alt)
   apply (erule order_le_less_trans[rotated])
   apply (simp add: unsigned_of_nat take_bit_eq_mod)
   done
 
 lemma unat_mask:
   "unat (mask n :: 'a :: len word) = 2 ^ (min n (LENGTH('a))) - 1"
   apply (subst min.commute)
   apply (simp add: mask_eq_decr_exp not_less min_def  split: if_split_asm)
   apply (intro conjI impI)
    apply (simp add: unat_sub_if_size)
    apply (simp add: power_overflow word_size)
   apply (simp add: unat_sub_if_size)
   done
 
 lemma mask_over_length:
   "LENGTH('a) \<le> n \<Longrightarrow> mask n = (-1::'a::len word)"
   by (simp add: mask_eq_decr_exp)
 
 lemma Suc_2p_unat_mask:
   "n < LENGTH('a) \<Longrightarrow> Suc (2 ^ n * k + unat (mask n :: 'a::len word)) = 2 ^ n * (k+1)"
   by (simp add: unat_mask)
 
 lemma sint_of_nat_ge_zero:
   "x < 2 ^ (LENGTH('a) - 1) \<Longrightarrow> sint (of_nat x :: 'a :: len word) \<ge> 0"
   by (simp add: bit_iff_odd signed_of_nat)
 
 lemma int_eq_sint:
   "x < 2 ^ (LENGTH('a) - 1) \<Longrightarrow> sint (of_nat x :: 'a :: len word) = int x"
   apply transfer
   apply (rule signed_take_bit_int_eq_self)
    apply simp_all
   apply (metis negative_zle numeral_power_eq_of_nat_cancel_iff)
   done
 
 lemma sint_of_nat_le:
   "\<lbrakk> b < 2 ^ (LENGTH('a) - 1); a \<le> b \<rbrakk>
    \<Longrightarrow> sint (of_nat a :: 'a :: len word) \<le> sint (of_nat b :: 'a :: len word)"
   apply (cases \<open>LENGTH('a)\<close>)
   apply simp_all
   apply transfer
   apply (subst signed_take_bit_eq_if_positive)
    apply (simp add: bit_simps)
   apply (metis bit_take_bit_iff nat_less_le order_less_le_trans take_bit_nat_eq_self_iff)
   apply (subst signed_take_bit_eq_if_positive)
     apply (simp add: bit_simps)
   apply (metis bit_take_bit_iff nat_less_le take_bit_nat_eq_self_iff)
     apply (simp flip: of_nat_take_bit add: take_bit_nat_eq_self)
   done
 
 lemma word_le_not_less:
   "((b::'a::len word) \<le> a) = (\<not>(a < b))"
   by fastforce
 
 lemma less_is_non_zero_p1:
   fixes a :: "'a :: len word"
   shows "a < k \<Longrightarrow> a + 1 \<noteq> 0"
   apply (erule contrapos_pn)
   apply (drule max_word_wrap)
   apply (simp add: not_less)
   done
 
 lemma unat_add_lem':
   "(unat x + unat y < 2 ^ LENGTH('a)) \<Longrightarrow>
     (unat (x + y :: 'a :: len word) = unat x + unat y)"
   by (subst unat_add_lem[symmetric], assumption)
 
 lemma word_less_two_pow_divI:
   "\<lbrakk> (x :: 'a::len word) < 2 ^ (n - m); m \<le> n; n < LENGTH('a) \<rbrakk> \<Longrightarrow> x < 2 ^ n div 2 ^ m"
   apply (simp add: word_less_nat_alt)
   apply (subst unat_word_ariths)
   apply (subst mod_less)
    apply (rule order_le_less_trans [OF div_le_dividend])
    apply (rule unat_lt2p)
   apply (simp add: power_sub)
   done
 
 lemma word_less_two_pow_divD:
   "\<lbrakk> (x :: 'a::len word) < 2 ^ n div 2 ^ m \<rbrakk>
      \<Longrightarrow> n \<ge> m \<and> (x < 2 ^ (n - m))"
   apply (cases "n < LENGTH('a)")
    apply (cases "m < LENGTH('a)")
     apply (simp add: word_less_nat_alt)
     apply (subst(asm) unat_word_ariths)
     apply (subst(asm) mod_less)
      apply (rule order_le_less_trans [OF div_le_dividend])
      apply (rule unat_lt2p)
     apply (clarsimp dest!: less_two_pow_divD)
    apply (simp add: power_overflow)
    apply (simp add: word_div_def)
   apply (simp add: power_overflow word_div_def)
   done
 
 lemma of_nat_less_two_pow_div_set:
   "\<lbrakk> n < LENGTH('a) \<rbrakk> \<Longrightarrow>
    {x. x < (2 ^ n div 2 ^ m :: 'a::len word)}
       = of_nat ` {k. k < 2 ^ n div 2 ^ m}"
   apply (simp add: image_def)
   apply (safe dest!: word_less_two_pow_divD less_two_pow_divD
              intro!: word_less_two_pow_divI)
    apply (rule_tac x="unat x" in exI)
    apply (simp add: power_sub[symmetric])
    apply (subst unat_power_lower[symmetric, where 'a='a])
     apply simp
    apply (erule unat_mono)
   apply (subst word_unat_power)
   apply (rule of_nat_mono_maybe)
    apply (rule power_strict_increasing)
     apply simp
    apply simp
   apply assumption
   done
 
 lemma ucast_less:
   "LENGTH('b) < LENGTH('a) \<Longrightarrow>
    (ucast (x :: 'b :: len word) :: ('a :: len word)) < 2 ^ LENGTH('b)"
   by transfer simp
 
 lemma ucast_range_less:
   "LENGTH('a :: len) < LENGTH('b :: len) \<Longrightarrow>
    range (ucast :: 'a word \<Rightarrow> 'b word) = {x. x < 2 ^ len_of TYPE ('a)}"
   apply safe
    apply (erule ucast_less)
   apply (simp add: image_def)
   apply (rule_tac x="ucast x" in exI)
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps)
   apply (metis bit_take_bit_iff take_bit_word_eq_self_iff)
   done
 
 lemma word_power_less_diff:
   "\<lbrakk>2 ^ n * q < (2::'a::len word) ^ m; q < 2 ^ (LENGTH('a) - n)\<rbrakk> \<Longrightarrow> q < 2 ^ (m - n)"
   apply (case_tac "m \<ge> LENGTH('a)")
    apply (simp add: power_overflow)
   apply (case_tac "n \<ge> LENGTH('a)")
    apply (simp add: power_overflow)
   apply (cases "n = 0")
    apply simp
   apply (subst word_less_nat_alt)
   apply (subst unat_power_lower)
    apply simp
   apply (rule nat_power_less_diff)
   apply (simp add: word_less_nat_alt)
   apply (subst (asm) iffD1 [OF unat_mult_lem])
    apply (simp add:nat_less_power_trans)
   apply simp
   done
 
 lemma word_less_sub_1:
   "x < (y :: 'a :: len word) \<Longrightarrow> x \<le> y - 1"
   by (fact word_le_minus_one_leq)
 
 lemma word_sub_mono2:
   "\<lbrakk> a + b \<le> c + d; c \<le> a; b \<le> a + b; d \<le> c + d \<rbrakk>
     \<Longrightarrow> b \<le> (d :: 'a :: len word)"
   apply (drule(1) word_sub_mono)
     apply simp
    apply simp
   apply simp
   done
 
 lemma word_not_le:
   "(\<not> x \<le> (y :: 'a :: len word)) = (y < x)"
   by fastforce
 
 lemma word_subset_less:
   "\<lbrakk> {x .. x + r - 1} \<subseteq> {y .. y + s - 1};
      x \<le> x + r - 1; y \<le> y + (s :: 'a :: len word) - 1;
      s \<noteq> 0 \<rbrakk>
      \<Longrightarrow> r \<le> s"
   apply (frule subsetD[where c=x])
    apply simp
   apply (drule subsetD[where c="x + r - 1"])
    apply simp
   apply (clarsimp simp: add_diff_eq[symmetric])
   apply (drule(1) word_sub_mono2)
     apply (simp_all add: olen_add_eqv[symmetric])
   apply (erule word_le_minus_cancel)
   apply (rule ccontr)
   apply (simp add: word_not_le)
   done
 
 lemma uint_power_lower:
   "n < LENGTH('a) \<Longrightarrow> uint (2 ^ n :: 'a :: len word) = (2 ^ n :: int)"
   by (rule uint_2p_alt)
 
 lemma power_le_mono:
   "\<lbrakk>2 ^ n \<le> (2::'a::len word) ^ m; n < LENGTH('a); m < LENGTH('a)\<rbrakk>
    \<Longrightarrow> n \<le> m"
   apply (clarsimp simp add: le_less)
   apply safe
   apply (simp add: word_less_nat_alt)
   apply (simp only: uint_arith_simps(3))
   apply (drule uint_power_lower)+
   apply simp
   done
 
 lemma two_power_eq:
   "\<lbrakk>n < LENGTH('a); m < LENGTH('a)\<rbrakk>
    \<Longrightarrow> ((2::'a::len word) ^ n = 2 ^ m) = (n = m)"
   apply safe
   apply (rule order_antisym)
    apply (simp add: power_le_mono[where 'a='a])+
   done
 
 lemma unat_less_helper:
   "x < of_nat n \<Longrightarrow> unat x < n"
   apply (simp add: word_less_nat_alt)
   apply (erule order_less_le_trans)
   apply (simp add: take_bit_eq_mod unsigned_of_nat)
   done
 
 lemma nat_uint_less_helper:
   "nat (uint y) = z \<Longrightarrow> x < y \<Longrightarrow> nat (uint x) < z"
   apply (erule subst)
   apply (subst unat_eq_nat_uint [symmetric])
   apply (subst unat_eq_nat_uint [symmetric])
   by (simp add: unat_mono)
 
 lemma of_nat_0:
   "\<lbrakk>of_nat n = (0::'a::len word); n < 2 ^ LENGTH('a)\<rbrakk> \<Longrightarrow> n = 0"
   by (auto simp add: word_of_nat_eq_0_iff)
 
 lemma of_nat_inj:
   "\<lbrakk>x < 2 ^ LENGTH('a); y < 2 ^ LENGTH('a)\<rbrakk> \<Longrightarrow>
    (of_nat x = (of_nat y :: 'a :: len word)) = (x = y)"
   by (metis unat_of_nat_len)
 
 lemma div_to_mult_word_lt:
   "\<lbrakk> (x :: 'a :: len word) \<le> y div z \<rbrakk> \<Longrightarrow> x * z \<le> y"
   apply (cases "z = 0")
    apply simp
   apply (simp add: word_neq_0_conv)
   apply (rule order_trans)
    apply (erule(1) word_mult_le_mono1)
    apply (simp add: unat_div)
    apply (rule order_le_less_trans [OF div_mult_le])
    apply simp
   apply (rule word_div_mult_le)
   done
 
 lemma ucast_ucast_mask:
   "(ucast :: 'a :: len word \<Rightarrow> 'b :: len word) (ucast x) = x AND mask (len_of TYPE ('a))"
   apply (simp flip: take_bit_eq_mask)
   apply transfer
   apply (simp add: ac_simps)
   done
 
 lemma ucast_ucast_len:
   "\<lbrakk> x < 2 ^ LENGTH('b) \<rbrakk> \<Longrightarrow> ucast (ucast x::'b::len word) = (x::'a::len word)"
   apply (subst ucast_ucast_mask)
   apply (erule less_mask_eq)
   done
 
 lemma ucast_ucast_id:
   "LENGTH('a) < LENGTH('b) \<Longrightarrow> ucast (ucast (x::'a::len word)::'b::len word) = x"
   by (auto intro: ucast_up_ucast_id simp: is_up_def source_size_def target_size_def word_size)
 
 lemma unat_ucast:
   "unat (ucast x :: ('a :: len) word) = unat x mod 2 ^ (LENGTH('a))"
 proof -
   have \<open>2 ^ LENGTH('a) = nat (2 ^ LENGTH('a))\<close>
     by simp
   moreover have \<open>unat (ucast x :: 'a word) = unat x mod nat (2 ^ LENGTH('a))\<close>
     by transfer (simp flip: nat_mod_distrib take_bit_eq_mod)
   ultimately show ?thesis
     by (simp only:)
 qed
 
 lemma ucast_less_ucast:
   "LENGTH('a) \<le> LENGTH('b) \<Longrightarrow>
    (ucast x < ((ucast (y :: 'a::len word)) :: 'b::len word)) = (x < y)"
   apply (simp add: word_less_nat_alt unat_ucast)
   apply (subst mod_less)
    apply(rule less_le_trans[OF unat_lt2p], simp)
   apply (subst mod_less)
    apply(rule less_le_trans[OF unat_lt2p], simp)
   apply simp
   done
 
 \<comment> \<open>This weaker version was previously called @{text ucast_less_ucast}. We retain it to
     support existing proofs.\<close>
 lemmas ucast_less_ucast_weak = ucast_less_ucast[OF order.strict_implies_order]
 
 lemma unat_Suc2:
   fixes n :: "'a :: len word"
   shows
   "n \<noteq> -1 \<Longrightarrow> unat (n + 1) = Suc (unat n)"
   apply (subst add.commute, rule unatSuc)
   apply (subst eq_diff_eq[symmetric], simp add: minus_equation_iff)
   done
 
 lemma word_div_1:
   "(n :: 'a :: len word) div 1 = n"
   by (fact bits_div_by_1)
 
 lemma word_minus_one_le:
   "-1 \<le> (x :: 'a :: len word) = (x = -1)"
   by (fact word_order.extremum_unique)
 
 lemma up_scast_inj:
       "\<lbrakk> scast x = (scast y :: 'b :: len word); size x \<le> LENGTH('b) \<rbrakk>
          \<Longrightarrow> x = y"
   apply transfer
   apply (cases \<open>LENGTH('a)\<close>)
   apply simp_all
   apply (metis order_refl take_bit_signed_take_bit take_bit_tightened)
   done
 
 lemma up_scast_inj_eq:
   "LENGTH('a) \<le> len_of TYPE ('b) \<Longrightarrow>
   (scast x = (scast y::'b::len word)) = (x = (y::'a::len word))"
   by (fastforce dest: up_scast_inj simp: word_size)
 
 lemma word_le_add:
   fixes x :: "'a :: len word"
   shows "x \<le> y \<Longrightarrow> \<exists>n. y = x + of_nat n"
   by (rule exI [where x = "unat (y - x)"]) simp
 
 lemma word_plus_mcs_4':
   fixes x :: "'a :: len word"
   shows "\<lbrakk>x + v \<le> x + w; x \<le> x + v\<rbrakk> \<Longrightarrow> v \<le> w"
   apply (rule word_plus_mcs_4)
    apply (simp add: add.commute)
   apply (simp add: add.commute)
   done
 
 lemma unat_eq_1:
   \<open>unat x = Suc 0 \<longleftrightarrow> x = 1\<close>
   by (auto intro!: unsigned_word_eqI [where ?'a = nat])
 
 lemma word_unat_Rep_inject1:
   \<open>unat x = unat 1 \<longleftrightarrow> x = 1\<close>
   by (simp add: unat_eq_1)
 
 lemma and_not_mask_twice:
   "(w AND NOT (mask n)) AND NOT (mask m) = w AND NOT (mask (max m n))"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma word_less_cases:
   "x < y \<Longrightarrow> x = y - 1 \<or> x < y - (1 ::'a::len word)"
   apply (drule word_less_sub_1)
   apply (drule order_le_imp_less_or_eq)
   apply auto
   done
 
 lemma mask_and_mask:
   "mask a AND mask b = (mask (min a b) :: 'a::len word)"
   by (simp flip: take_bit_eq_mask ac_simps)
 
 lemma mask_eq_0_eq_x:
   "(x AND w = 0) = (x AND NOT w = x)"
   for x w :: \<open>'a::len word\<close>
   using word_plus_and_or_coroll2[where x=x and w=w]
   by auto
 
 lemma mask_eq_x_eq_0:
   "(x AND w = x) = (x AND NOT w = 0)"
   for x w :: \<open>'a::len word\<close>
   using word_plus_and_or_coroll2[where x=x and w=w]
   by auto
 
 lemma compl_of_1: "NOT 1 = (-2 :: 'a :: len word)"
   by (fact not_one_eq)
 
 lemma split_word_eq_on_mask:
   "(x = y) = (x AND m = y AND m \<and> x AND NOT m = y AND NOT m)"
   for x y m :: \<open>'a::len word\<close>
   apply transfer
   apply (simp add: bit_eq_iff)
   apply (auto simp add: bit_simps ac_simps)
   done
 
 lemma word_FF_is_mask:
   "0xFF = (mask 8 :: 'a::len word)"
   by (simp add: mask_eq_decr_exp)
 
 lemma word_1FF_is_mask:
   "0x1FF = (mask 9 :: 'a::len word)"
   by (simp add: mask_eq_decr_exp)
 
 lemma ucast_of_nat_small:
   "x < 2 ^ LENGTH('a) \<Longrightarrow> ucast (of_nat x :: 'a :: len word) = (of_nat x :: 'b :: len word)"
   apply transfer
   apply (auto simp add: take_bit_of_nat min_def not_le)
   apply (metis linorder_not_less min_def take_bit_nat_eq_self take_bit_take_bit)
   done
 
 lemma word_le_make_less:
   fixes x :: "'a :: len word"
   shows "y \<noteq> -1 \<Longrightarrow> (x \<le> y) = (x < (y + 1))"
   apply safe
   apply (erule plus_one_helper2)
   apply (simp add: eq_diff_eq[symmetric])
   done
 
 lemmas finite_word = finite [where 'a="'a::len word"]
 
 lemma word_to_1_set:
   "{0 ..< (1 :: 'a :: len word)} = {0}"
   by fastforce
 
 lemma word_leq_minus_one_le:
   fixes x :: "'a::len word"
   shows "\<lbrakk>y \<noteq> 0; x \<le> y - 1 \<rbrakk> \<Longrightarrow> x < y"
   using le_m1_iff_lt word_neq_0_conv by blast
 
 lemma word_count_from_top:
   "n \<noteq> 0 \<Longrightarrow> {0 ..< n :: 'a :: len word} = {0 ..< n - 1} \<union> {n - 1}"
   apply (rule set_eqI, rule iffI)
    apply simp
    apply (drule word_le_minus_one_leq)
    apply (rule disjCI)
    apply simp
   apply simp
   apply (erule word_leq_minus_one_le)
   apply fastforce
   done
 
 lemma word_minus_one_le_leq:
   "\<lbrakk> x - 1 < y \<rbrakk> \<Longrightarrow> x \<le> (y :: 'a :: len word)"
   apply (cases "x = 0")
    apply simp
   apply (simp add: word_less_nat_alt word_le_nat_alt)
   apply (subst(asm) unat_minus_one)
    apply (simp add: word_less_nat_alt)
   apply (cases "unat x")
    apply (simp add: unat_eq_zero)
   apply arith
   done
 
-lemma word_div_less:
-  "m < n \<Longrightarrow> m div n = 0" for m :: "'a :: len word"
-  by (simp add: unat_mono word_arith_nat_defs(6))
-
 lemma word_must_wrap:
   "\<lbrakk> x \<le> n - 1; n \<le> x \<rbrakk> \<Longrightarrow> n = (0 :: 'a :: len word)"
   using dual_order.trans sub_wrap word_less_1 by blast
 
 lemma range_subset_card:
   "\<lbrakk> {a :: 'a :: len word .. b} \<subseteq> {c .. d}; b \<ge> a \<rbrakk> \<Longrightarrow> d \<ge> c \<and> d - c \<ge> b - a"
   using word_sub_le word_sub_mono by fastforce
 
 lemma less_1_simp:
   "n - 1 < m = (n \<le> (m :: 'a :: len word) \<and> n \<noteq> 0)"
   by unat_arith
 
 lemma word_power_mod_div:
   fixes x :: "'a::len word"
   shows "\<lbrakk> n < LENGTH('a); m < LENGTH('a)\<rbrakk>
   \<Longrightarrow> x mod 2 ^ n div 2 ^ m = x div 2 ^ m mod 2 ^ (n - m)"
   apply (simp add: word_arith_nat_div unat_mod power_mod_div)
   apply (subst unat_arith_simps(3))
   apply (subst unat_mod)
   apply (subst unat_of_nat)+
   apply (simp add: mod_mod_power min.commute)
   done
 
 lemma word_range_minus_1':
   fixes a :: "'a :: len word"
   shows "a \<noteq> 0 \<Longrightarrow> {a - 1<..b} = {a..b}"
   by (simp add: greaterThanAtMost_def atLeastAtMost_def greaterThan_def atLeast_def less_1_simp)
 
 lemma word_range_minus_1:
   fixes a :: "'a :: len word"
   shows "b \<noteq> 0 \<Longrightarrow> {a..b - 1} = {a..<b}"
   apply (simp add: atLeastLessThan_def atLeastAtMost_def atMost_def lessThan_def)
   apply (rule arg_cong [where f = "\<lambda>x. {a..} \<inter> x"])
   apply rule
    apply clarsimp
    apply (erule contrapos_pp)
    apply (simp add: linorder_not_less linorder_not_le word_must_wrap)
   apply (clarsimp)
   apply (drule word_le_minus_one_leq)
   apply (auto simp: word_less_sub_1)
   done
 
 lemma ucast_nat_def:
   "of_nat (unat x) = (ucast :: 'a :: len word \<Rightarrow> 'b :: len word) x"
   by transfer simp
 
 lemma overflow_plus_one_self:
   "(1 + p \<le> p) = (p = (-1 :: 'a :: len word))"
   apply rule
   apply (rule ccontr)
    apply (drule plus_one_helper2)
    apply (rule notI)
    apply (drule arg_cong[where f="\<lambda>x. x - 1"])
    apply simp
    apply (simp add: field_simps)
   apply simp
   done
 
 lemma plus_1_less:
   "(x + 1 \<le> (x :: 'a :: len word)) = (x = -1)"
   apply (rule iffI)
    apply (rule ccontr)
    apply (cut_tac plus_one_helper2[where x=x, OF order_refl])
     apply simp
    apply clarsimp
    apply (drule arg_cong[where f="\<lambda>x. x - 1"])
    apply simp
   apply simp
   done
 
 lemma pos_mult_pos_ge:
   "[|x > (0::int); n>=0 |] ==> n * x >= n*1"
   apply (simp only: mult_left_mono)
   done
 
 lemma word_plus_strict_mono_right:
   fixes x :: "'a :: len word"
   shows "\<lbrakk>y < z; x \<le> x + z\<rbrakk> \<Longrightarrow> x + y < x + z"
   by unat_arith
 
 lemma word_div_mult:
   "0 < c \<Longrightarrow> a < b * c \<Longrightarrow> a div c < b" for a b c :: "'a::len word"
   by (rule classical)
      (use div_to_mult_word_lt [of b a c] in
       \<open>auto simp add: word_less_nat_alt word_le_nat_alt unat_div\<close>)
 
 lemma word_less_power_trans_ofnat:
   "\<lbrakk>n < 2 ^ (m - k); k \<le> m; m < LENGTH('a)\<rbrakk>
    \<Longrightarrow> of_nat n * 2 ^ k < (2::'a::len word) ^ m"
   apply (subst mult.commute)
   apply (rule word_less_power_trans)
     apply (simp_all add: word_less_nat_alt unsigned_of_nat)
   using take_bit_nat_less_eq_self
   apply (rule le_less_trans)
   apply assumption
   done
 
 lemma word_1_le_power:
   "n < LENGTH('a) \<Longrightarrow> (1 :: 'a :: len word) \<le> 2 ^ n"
   by (rule inc_le[where i=0, simplified], erule iffD2[OF p2_gt_0])
 
 lemma unat_1_0:
   "1 \<le> (x::'a::len word) = (0 < unat x)"
   by (auto simp add: word_le_nat_alt)
 
 lemma x_less_2_0_1':
   fixes x :: "'a::len word"
   shows "\<lbrakk>LENGTH('a) \<noteq> 1; x < 2\<rbrakk> \<Longrightarrow> x = 0 \<or> x = 1"
   apply (cases \<open>2 \<le> LENGTH('a)\<close>)
   apply simp_all
   apply transfer
   apply auto
   apply (metis add.commute add.right_neutral even_two_times_div_two mod_div_trivial mod_pos_pos_trivial mult.commute mult_zero_left not_less not_take_bit_negative odd_two_times_div_two_succ)
   done
 
 lemmas word_add_le_iff2 = word_add_le_iff [folded no_olen_add_nat]
 
 lemma of_nat_power:
   shows "\<lbrakk> p < 2 ^ x; x < len_of TYPE ('a) \<rbrakk> \<Longrightarrow> of_nat p < (2 :: 'a :: len word) ^ x"
   apply (rule order_less_le_trans)
    apply (rule of_nat_mono_maybe)
     apply (erule power_strict_increasing)
     apply simp
    apply assumption
   apply (simp add: word_unat_power del: of_nat_power)
   done
 
 lemma of_nat_n_less_equal_power_2:
   "n < LENGTH('a::len) \<Longrightarrow> ((of_nat n)::'a word) < 2 ^ n"
   apply (induct n)
    apply clarsimp
   apply clarsimp
   apply (metis of_nat_power n_less_equal_power_2 of_nat_Suc power_Suc)
   done
 
 lemma eq_mask_less:
   fixes w :: "'a::len word"
   assumes eqm: "w = w AND mask n"
   and      sz: "n < len_of TYPE ('a)"
   shows "w < (2::'a word) ^ n"
   by (subst eqm, rule and_mask_less' [OF sz])
 
 lemma of_nat_mono_maybe':
   fixes Y :: "nat"
   assumes xlt: "x < 2 ^ len_of TYPE ('a)"
   assumes ylt: "y < 2 ^ len_of TYPE ('a)"
   shows   "(y < x) = (of_nat y < (of_nat x :: 'a :: len word))"
   apply (subst word_less_nat_alt)
   apply (subst unat_of_nat)+
   apply (subst mod_less)
    apply (rule ylt)
   apply (subst mod_less)
    apply (rule xlt)
   apply simp
   done
 
 lemma of_nat_mono_maybe_le:
   "\<lbrakk>x < 2 ^ LENGTH('a); y < 2 ^ LENGTH('a)\<rbrakk> \<Longrightarrow>
   (y \<le> x) = ((of_nat y :: 'a :: len word) \<le> of_nat x)"
   apply (clarsimp simp: le_less)
   apply (rule disj_cong)
    apply (rule of_nat_mono_maybe', assumption+)
   apply auto
   using of_nat_inj apply blast
   done
 
 lemma mask_AND_NOT_mask:
   "(w AND NOT (mask n)) AND mask n = 0"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma AND_NOT_mask_plus_AND_mask_eq:
   "(w AND NOT (mask n)) + (w AND mask n) = w"
   for w :: \<open>'a::len word\<close>
   apply (subst disjunctive_add)
   apply (auto simp add: bit_simps)
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps)
   done
 
 lemma mask_eqI:
   fixes x :: "'a :: len word"
   assumes m1: "x AND mask n = y AND mask n"
   and     m2: "x AND NOT (mask n) = y AND NOT (mask n)"
   shows "x = y"
 proof -
   have *: \<open>x = x AND mask n OR x AND NOT (mask n)\<close> for x :: \<open>'a word\<close>
     by (rule bit_word_eqI) (auto simp add: bit_simps)
   from assms * [of x] * [of y] show ?thesis
     by simp
 qed
 
 lemma neq_0_no_wrap:
   fixes x :: "'a :: len word"
   shows "\<lbrakk> x \<le> x + y; x \<noteq> 0 \<rbrakk> \<Longrightarrow> x + y \<noteq> 0"
   by clarsimp
 
 lemma unatSuc2:
   fixes n :: "'a :: len word"
   shows "n + 1 \<noteq> 0 \<Longrightarrow> unat (n + 1) = Suc (unat n)"
   by (simp add: add.commute unatSuc)
 
 lemma word_of_nat_le:
   "n \<le> unat x \<Longrightarrow> of_nat n \<le> x"
   apply (simp add: word_le_nat_alt unat_of_nat)
   apply (erule order_trans[rotated])
   apply (simp add: take_bit_eq_mod)
   done
 
 lemma word_unat_less_le:
   "a \<le> of_nat b \<Longrightarrow> unat a \<le> b"
   by (metis eq_iff le_cases le_unat_uoi word_of_nat_le)
 
 lemma mask_Suc_0 : "mask (Suc 0) = (1 :: 'a::len word)"
   by (simp add: mask_eq_decr_exp)
 
 lemma bool_mask':
   fixes x :: "'a :: len word"
   shows "2 < LENGTH('a) \<Longrightarrow> (0 < x AND 1) = (x AND 1 = 1)"
   by (simp add: and_one_eq mod_2_eq_odd)
 
 lemma ucast_ucast_add:
   fixes x :: "'a :: len word"
   fixes y :: "'b :: len word"
   shows
   "LENGTH('b) \<ge> LENGTH('a) \<Longrightarrow>
     ucast (ucast x + y) = x + ucast y"
   apply transfer
   apply simp
   apply (subst (2) take_bit_add [symmetric])
   apply (subst take_bit_add [symmetric])
   apply simp
   done
 
 lemma lt1_neq0:
   fixes x :: "'a :: len word"
   shows "(1 \<le> x) = (x \<noteq> 0)" by unat_arith
 
 lemma word_plus_one_nonzero:
   fixes x :: "'a :: len word"
   shows "\<lbrakk>x \<le> x + y; y \<noteq> 0\<rbrakk> \<Longrightarrow> x + 1 \<noteq> 0"
   apply (subst lt1_neq0 [symmetric])
   apply (subst olen_add_eqv [symmetric])
   apply (erule word_random)
   apply (simp add: lt1_neq0)
   done
 
 lemma word_sub_plus_one_nonzero:
   fixes n :: "'a :: len word"
   shows "\<lbrakk>n' \<le> n; n' \<noteq> 0\<rbrakk> \<Longrightarrow> (n - n') + 1 \<noteq> 0"
   apply (subst lt1_neq0 [symmetric])
   apply (subst olen_add_eqv [symmetric])
   apply (rule word_random [where x' = n'])
    apply simp
    apply (erule word_sub_le)
   apply (simp add: lt1_neq0)
   done
 
 lemma word_le_minus_mono_right:
   fixes x :: "'a :: len word"
   shows "\<lbrakk> z \<le> y; y \<le> x; z \<le> x \<rbrakk> \<Longrightarrow> x - y \<le> x - z"
   apply (rule word_sub_mono)
      apply simp
     apply assumption
    apply (erule word_sub_le)
   apply (erule word_sub_le)
   done
 
 lemma word_0_sle_from_less:
   \<open>0 \<le>s x\<close> if \<open>x < 2 ^ (LENGTH('a) - 1)\<close> for x :: \<open>'a::len word\<close>
   using that
   apply transfer
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply (metis bit_take_bit_iff min_def nat_less_le not_less_eq take_bit_int_eq_self_iff take_bit_take_bit)
   done
 
 lemma ucast_sub_ucast:
   fixes x :: "'a::len word"
   assumes "y \<le> x"
   assumes T: "LENGTH('a) \<le> LENGTH('b)"
   shows "ucast (x - y) = (ucast x - ucast y :: 'b::len word)"
 proof -
   from T
   have P: "unat x < 2 ^ LENGTH('b)" "unat y < 2 ^ LENGTH('b)"
     by (fastforce intro!: less_le_trans[OF unat_lt2p])+
   then show ?thesis
     by (simp add: unat_arith_simps unat_ucast assms[simplified unat_arith_simps])
 qed
 
 lemma word_1_0:
   "\<lbrakk>a + (1::('a::len) word) \<le> b; a < of_nat x\<rbrakk> \<Longrightarrow> a < b"
   apply transfer
   apply (subst (asm) take_bit_incr_eq)
    apply (auto simp add: diff_less_eq)
   using take_bit_int_less_exp le_less_trans by blast
 
 lemma unat_of_nat_less:"\<lbrakk> a < b; unat b = c \<rbrakk> \<Longrightarrow> a < of_nat c"
   by fastforce
 
 lemma word_le_plus_1: "\<lbrakk> (y::('a::len) word) < y + n; a < n \<rbrakk> \<Longrightarrow> y + a \<le> y + a + 1"
   by unat_arith
 
 lemma word_le_plus:"\<lbrakk>(a::('a::len) word) < a + b; c < b\<rbrakk> \<Longrightarrow> a \<le> a + c"
   by (metis order_less_imp_le word_random)
 
 lemma sint_minus1 [simp]: "(sint x = -1) = (x = -1)"
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply transfer
+  apply (simp only: flip: signed_take_bit_eq_iff_take_bit_eq)
   apply simp
-  apply (simp flip: signed_take_bit_eq_iff_take_bit_eq)
   done
 
 lemma sint_0 [simp]: "(sint x = 0) = (x = 0)"
   by (fact signed_eq_0_iff)
 
 (* It is not always that case that "sint 1 = 1", because of 1-bit word sizes.
  * This lemma produces the different cases. *)
 lemma sint_1_cases:
   P if \<open>\<lbrakk> len_of TYPE ('a::len) = 1; (a::'a word) = 0; sint a = 0 \<rbrakk> \<Longrightarrow> P\<close>
      \<open>\<lbrakk> len_of TYPE ('a) = 1; a = 1; sint (1 :: 'a word) = -1 \<rbrakk> \<Longrightarrow> P\<close>
      \<open>\<lbrakk> len_of TYPE ('a) > 1; sint (1 :: 'a word) = 1 \<rbrakk> \<Longrightarrow> P\<close>
 proof (cases \<open>LENGTH('a) = 1\<close>)
   case True
   then have \<open>a = 0 \<or> a = 1\<close>
     by transfer auto
   with True that show ?thesis
     by auto
 next
   case False
   with that show ?thesis
     by (simp add: less_le Suc_le_eq)
 qed
 
 lemma sint_int_min:
   "sint (- (2 ^ (LENGTH('a) - Suc 0)) :: ('a::len) word) = - (2 ^ (LENGTH('a) - Suc 0))"
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply transfer
   apply (simp add: signed_take_bit_int_eq_self)
   done
 
 lemma sint_int_max_plus_1:
   "sint (2 ^ (LENGTH('a) - Suc 0) :: ('a::len) word) = - (2 ^ (LENGTH('a) - Suc 0))"
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply (subst word_of_int_2p [symmetric])
   apply (subst int_word_sint)
   apply simp
   done
 
 lemma uint_range':
   \<open>0 \<le> uint x \<and> uint x < 2 ^ LENGTH('a)\<close>
   for x :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma sint_of_int_eq:
   "\<lbrakk> - (2 ^ (LENGTH('a) - 1)) \<le> x; x < 2 ^ (LENGTH('a) - 1) \<rbrakk> \<Longrightarrow> sint (of_int x :: ('a::len) word) = x"
   by (simp add: signed_take_bit_int_eq_self signed_of_int)
 
 lemma of_int_sint:
   "of_int (sint a) = a"
   by simp
 
 lemma sint_ucast_eq_uint:
     "\<lbrakk> \<not> is_down (ucast :: ('a::len word \<Rightarrow> 'b::len word)) \<rbrakk>
             \<Longrightarrow> sint ((ucast :: ('a::len word \<Rightarrow> 'b::len word)) x) = uint x"
   apply transfer
   apply (simp add: signed_take_bit_take_bit)
   done
 
 lemma word_less_nowrapI':
   "(x :: 'a :: len word) \<le> z - k \<Longrightarrow> k \<le> z \<Longrightarrow> 0 < k \<Longrightarrow> x < x + k"
   by uint_arith
 
 lemma mask_plus_1:
   "mask n + 1 = (2 ^ n :: 'a::len word)"
   by (clarsimp simp: mask_eq_decr_exp)
 
 lemma unat_inj: "inj unat"
   by (metis eq_iff injI word_le_nat_alt)
 
 lemma unat_ucast_upcast:
   "is_up (ucast :: 'b word \<Rightarrow> 'a word)
       \<Longrightarrow> unat (ucast x :: ('a::len) word) = unat (x :: ('b::len) word)"
   unfolding ucast_eq unat_eq_nat_uint
   apply transfer
   apply simp
   done
 
 lemma ucast_mono:
   "\<lbrakk> (x :: 'b :: len word) < y; y < 2 ^ LENGTH('a) \<rbrakk>
    \<Longrightarrow> ucast x < ((ucast y) :: 'a :: len word)"
   apply (simp only: flip: ucast_nat_def)
   apply (rule of_nat_mono_maybe)
   apply (rule unat_less_helper)
   apply simp
   apply (simp add: word_less_nat_alt)
   done
 
 lemma ucast_mono_le:
   "\<lbrakk>x \<le> y; y < 2 ^ LENGTH('b)\<rbrakk> \<Longrightarrow> (ucast (x :: 'a :: len word) :: 'b :: len word) \<le> ucast y"
   apply (simp only: flip: ucast_nat_def)
   apply (subst of_nat_mono_maybe_le[symmetric])
     apply (rule unat_less_helper)
     apply simp
    apply (rule unat_less_helper)
    apply (erule le_less_trans)
   apply (simp_all add: word_le_nat_alt)
   done
 
 lemma ucast_mono_le':
   "\<lbrakk> unat y < 2 ^ LENGTH('b); LENGTH('b::len) < LENGTH('a::len); x \<le> y \<rbrakk>
    \<Longrightarrow> ucast x \<le> (ucast y :: 'b word)" for x y :: \<open>'a::len word\<close>
   by (auto simp: word_less_nat_alt intro: ucast_mono_le)
 
 lemma neg_mask_add_mask:
   "((x:: 'a :: len word) AND NOT (mask n)) + (2 ^ n - 1) = x OR mask n"
   unfolding mask_2pm1 [symmetric]
   apply (subst word_plus_and_or_coroll; rule bit_word_eqI)
    apply (auto simp add: bit_simps)
   done
 
 lemma le_step_down_word:"\<lbrakk>(i::('a::len) word) \<le> n; i = n \<longrightarrow> P; i \<le> n - 1 \<longrightarrow> P\<rbrakk> \<Longrightarrow> P"
   by unat_arith
 
 lemma le_step_down_word_2:
   fixes x :: "'a::len word"
   shows "\<lbrakk>x \<le>  y; x \<noteq> y\<rbrakk> \<Longrightarrow> x \<le> y - 1"
   by (subst (asm) word_le_less_eq,
       clarsimp,
       simp add: word_le_minus_one_leq)
 
 lemma NOT_mask_AND_mask[simp]: "(w AND mask n) AND NOT (mask n) = 0"
   by (rule bit_eqI) (simp add: bit_simps)
 
 lemma and_and_not[simp]:"(a AND b) AND NOT b = 0"
   for a b :: \<open>'a::len word\<close>
   apply (subst word_bw_assocs(1))
   apply clarsimp
   done
 
 lemma ex_mask_1[simp]: "(\<exists>x. mask x = (1 :: 'a::len word))"
   apply (rule_tac x=1 in exI)
   apply (simp add:mask_eq_decr_exp)
   done
 
 lemma not_switch:"NOT a = x \<Longrightarrow> a = NOT x"
   by auto
 
 lemma test_bit_eq_iff: "bit u = bit v \<longleftrightarrow> u = v"
   for u v :: "'a::len word"
   by (auto intro: bit_eqI simp add: fun_eq_iff)
 
 lemma test_bit_size: "bit w n \<Longrightarrow> n < size w"
   for w :: "'a::len word"
   by transfer simp
 
 lemma word_eq_iff: "x = y \<longleftrightarrow> (\<forall>n<LENGTH('a). bit x n = bit y n)" (is \<open>?P \<longleftrightarrow> ?Q\<close>)
   for x y :: "'a::len word"
   by transfer (auto simp add: bit_eq_iff bit_take_bit_iff)
 
 lemma word_eqI: "(\<And>n. n < size u \<longrightarrow> bit u n = bit v n) \<Longrightarrow> u = v"
   for u :: "'a::len word"
   by (simp add: word_size word_eq_iff)
 
 lemma word_eqD: "u = v \<Longrightarrow> bit u x = bit v x"
   for u v :: "'a::len word"
   by simp
 
 lemma test_bit_bin': "bit w n \<longleftrightarrow> n < size w \<and> bit (uint w) n"
   by transfer (simp add: bit_take_bit_iff)
 
 lemmas test_bit_bin = test_bit_bin' [unfolded word_size]
 
 lemma word_test_bit_def:
   \<open>bit a = bit (uint a)\<close>
   by transfer (simp add: fun_eq_iff bit_take_bit_iff)
 
 lemmas test_bit_def' = word_test_bit_def [THEN fun_cong]
 
 lemma word_test_bit_transfer [transfer_rule]:
   "(rel_fun pcr_word (rel_fun (=) (=)))
     (\<lambda>x n. n < LENGTH('a) \<and> bit x n) (bit :: 'a::len word \<Rightarrow> _)"
   by transfer_prover
 
 lemma test_bit_wi:
   "bit (word_of_int x :: 'a::len word) n \<longleftrightarrow> n < LENGTH('a) \<and> bit x n"
   by transfer simp
 
 lemma word_ops_nth_size:
   "n < size x \<Longrightarrow>
     bit (x OR y) n = (bit x n | bit y n) \<and>
     bit (x AND y) n = (bit x n \<and> bit y n) \<and>
     bit (x XOR y) n = (bit x n \<noteq> bit y n) \<and>
     bit (NOT x) n = (\<not> bit x n)"
   for x :: "'a::len word"
   by transfer (simp add: bit_or_iff bit_and_iff bit_xor_iff bit_not_iff)
 
 lemma word_ao_nth:
   "bit (x OR y) n = (bit x n | bit y n) \<and>
     bit (x AND y) n = (bit x n \<and> bit y n)"
   for x :: "'a::len word"
   by transfer (auto simp add: bit_or_iff bit_and_iff)
 
 lemmas lsb0 = len_gt_0 [THEN word_ops_nth_size [unfolded word_size]]
 
 lemma nth_sint:
   fixes w :: "'a::len word"
   defines "l \<equiv> LENGTH('a)"
   shows "bit (sint w) n = (if n < l - 1 then bit w n else bit w (l - 1))"
   unfolding sint_uint l_def
   by (auto simp: bit_signed_take_bit_iff word_test_bit_def not_less min_def)
 
 lemma test_bit_2p: "bit (word_of_int (2 ^ n)::'a::len word) m \<longleftrightarrow> m = n \<and> m < LENGTH('a)"
   by transfer (auto simp add: bit_exp_iff)
 
 lemma nth_w2p: "bit ((2::'a::len word) ^ n) m \<longleftrightarrow> m = n \<and> m < LENGTH('a::len)"
   by transfer (auto simp add: bit_exp_iff)
 
 lemma bang_is_le: "bit x m \<Longrightarrow> 2 ^ m \<le> x"
   for x :: "'a::len word"
   apply (rule xtrans(3))
    apply (rule_tac [2] y = "x" in le_word_or2)
   apply (rule word_eqI)
   apply (auto simp add: word_ao_nth nth_w2p word_size)
   done
 
 lemmas msb0 = len_gt_0 [THEN diff_Suc_less, THEN word_ops_nth_size [unfolded word_size]]
 lemmas msb1 = msb0 [where i = 0]
 
 lemma test_bit_1 [iff]: "bit (1 :: 'a::len word) n \<longleftrightarrow> n = 0"
   by transfer (auto simp add: bit_1_iff)
 
 lemma nth_0: "\<not> bit (0 :: 'a::len word) n"
   by transfer simp
 
 lemma nth_minus1: "bit (-1 :: 'a::len word) n \<longleftrightarrow> n < LENGTH('a)"
   by transfer simp
 
 lemma nth_ucast:
   "bit (ucast w::'a::len word) n = (bit w n \<and> n < LENGTH('a))"
   by transfer (simp add: bit_take_bit_iff ac_simps)
 
 lemma drop_bit_numeral_bit0_1 [simp]:
   \<open>drop_bit (Suc 0) (numeral k) =
     (word_of_int (drop_bit (Suc 0) (take_bit LENGTH('a) (numeral k))) :: 'a::len word)\<close>
   by (metis Word_eq_word_of_int drop_bit_word.abs_eq of_int_numeral)
 
 lemma nth_mask:
   \<open>bit (mask n :: 'a::len word) i \<longleftrightarrow> i < n \<and> i < size (mask n :: 'a word)\<close>
   by (auto simp add: word_size Word.bit_mask_iff)
 
 lemma nth_slice: "bit (slice n w :: 'a::len word) m = (bit w (m + n) \<and> m < LENGTH('a))"
   apply (auto simp add: bit_simps less_diff_conv dest: bit_imp_le_length)
   using bit_imp_le_length
   apply fastforce
   done
 
 lemma test_bit_cat [OF refl]:
   "wc = word_cat a b \<Longrightarrow> bit wc n = (n < size wc \<and>
     (if n < size b then bit b n else bit a (n - size b)))"
   apply (simp add: word_size not_less; transfer)
        apply (auto simp add: bit_concat_bit_iff bit_take_bit_iff)
   done
 
 \<comment> \<open>keep quantifiers for use in simplification\<close>
 lemma test_bit_split':
   "word_split c = (a, b) \<longrightarrow>
     (\<forall>n m.
       bit b n = (n < size b \<and> bit c n) \<and>
       bit a m = (m < size a \<and> bit c (m + size b)))"
   by (auto simp add: word_split_bin' bit_unsigned_iff word_size bit_drop_bit_eq ac_simps
            dest: bit_imp_le_length)
 
 lemma test_bit_split:
   "word_split c = (a, b) \<Longrightarrow>
     (\<forall>n::nat. bit b n \<longleftrightarrow> n < size b \<and> bit c n) \<and>
     (\<forall>m::nat. bit a m \<longleftrightarrow> m < size a \<and> bit c (m + size b))"
   by (simp add: test_bit_split')
 
 lemma test_bit_split_eq:
   "word_split c = (a, b) \<longleftrightarrow>
     ((\<forall>n::nat. bit b n = (n < size b \<and> bit c n)) \<and>
      (\<forall>m::nat. bit a m = (m < size a \<and> bit c (m + size b))))"
   apply (rule_tac iffI)
    apply (rule_tac conjI)
     apply (erule test_bit_split [THEN conjunct1])
    apply (erule test_bit_split [THEN conjunct2])
   apply (case_tac "word_split c")
   apply (frule test_bit_split)
   apply (erule trans)
   apply (fastforce intro!: word_eqI simp add: word_size)
   done
 
 lemma test_bit_rcat:
   "sw = size (hd wl) \<Longrightarrow> rc = word_rcat wl \<Longrightarrow> bit rc n =
     (n < size rc \<and> n div sw < size wl \<and> bit ((rev wl) ! (n div sw)) (n mod sw))"
   for wl :: "'a::len word list"
   by (simp add: word_size word_rcat_def rev_map bit_horner_sum_uint_exp_iff bit_simps not_le)
 
 lemmas test_bit_cong = arg_cong [where f = "bit", THEN fun_cong]
 
 lemma max_test_bit: "bit (- 1::'a::len word) n \<longleftrightarrow> n < LENGTH('a)"
   by (fact nth_minus1)
 
 lemma map_nth_0 [simp]: "map (bit (0::'a::len word)) xs = replicate (length xs) False"
   by (simp flip: map_replicate_const)
 
 lemma word_and_1:
   "n AND 1 = (if bit n 0 then 1 else 0)" for n :: "_ word"
   by (rule bit_word_eqI) (auto simp add: bit_and_iff bit_1_iff intro: gr0I)
 
 lemma test_bit_1':
   "bit (1 :: 'a :: len word) n \<longleftrightarrow> 0 < LENGTH('a) \<and> n = 0"
   by simp
 
 lemma nth_w2p_same:
   "bit (2^n :: 'a :: len word) n = (n < LENGTH('a))"
   by (simp add: nth_w2p)
 
 lemma word_leI:
   "(\<And>n.  \<lbrakk>n < size (u::'a::len word); bit u n \<rbrakk> \<Longrightarrow> bit (v::'a::len word) n) \<Longrightarrow> u <= v"
   apply (rule order_trans [of u \<open>u AND v\<close> v])
    apply (rule eq_refl)
    apply (rule bit_word_eqI)
    apply (auto simp add: bit_simps word_and_le1 word_size)
   done
 
 lemma bang_eq:
   fixes x :: "'a::len word"
   shows "(x = y) = (\<forall>n. bit x n = bit y n)"
   by (auto intro!: bit_eqI)
 
 lemma neg_mask_test_bit:
   "bit (NOT(mask n) :: 'a :: len word) m = (n \<le> m \<and> m < LENGTH('a))"
   by (auto simp add: bit_simps)
 
 lemma upper_bits_unset_is_l2p:
   \<open>(\<forall>n' \<ge> n. n' < LENGTH('a) \<longrightarrow> \<not> bit p n') \<longleftrightarrow> (p < 2 ^ n)\<close> (is \<open>?P \<longleftrightarrow> ?Q\<close>)
     if \<open>n < LENGTH('a)\<close>
     for p :: "'a :: len word"
 proof
   assume ?Q
   then show ?P
     by (meson bang_is_le le_less_trans not_le word_power_increasing)
 next
   assume ?P
   have \<open>take_bit n p = p\<close>
   proof (rule bit_word_eqI)
     fix q
     assume \<open>q < LENGTH('a)\<close>
     show \<open>bit (take_bit n p) q \<longleftrightarrow> bit p q\<close>
     proof (cases \<open>q < n\<close>)
       case True
       then show ?thesis
         by (auto simp add: bit_simps)
     next
       case False
       then have \<open>n \<le> q\<close>
         by simp
       with \<open>?P\<close> \<open>q < LENGTH('a)\<close> have \<open>\<not> bit p q\<close>
         by simp
       then show ?thesis
         by (simp add: bit_simps)
     qed
   qed
   with that show ?Q
     using take_bit_word_eq_self_iff [of n p] by auto
 qed
 
 lemma less_2p_is_upper_bits_unset:
   "p < 2 ^ n \<longleftrightarrow> n < LENGTH('a) \<and> (\<forall>n' \<ge> n. n' < LENGTH('a) \<longrightarrow> \<not> bit p n')" for p :: "'a :: len word"
   by (meson le_less_trans le_mask_iff_lt_2n upper_bits_unset_is_l2p word_zero_le)
 
 lemma test_bit_over:
   "n \<ge> size (x::'a::len word) \<Longrightarrow> (bit x n) = False"
   by transfer auto
 
 lemma le_mask_high_bits:
   "w \<le> mask n \<longleftrightarrow> (\<forall>i \<in> {n ..< size w}. \<not> bit w i)"
   for w :: \<open>'a::len word\<close>
   apply (auto simp add: bit_simps word_size less_eq_mask_iff_take_bit_eq_self)
    apply (metis bit_take_bit_iff leD)
   apply (metis atLeastLessThan_iff leI take_bit_word_eq_self_iff upper_bits_unset_is_l2p)
   done
 
 lemma test_bit_conj_lt:
   "(bit x m \<and> m < LENGTH('a)) = bit x m" for x :: "'a :: len word"
   using test_bit_bin by blast
 
 lemma neg_test_bit:
   "bit (NOT x) n = (\<not> bit x n \<and> n < LENGTH('a))" for x :: "'a::len word"
   by (cases "n < LENGTH('a)") (auto simp add: test_bit_over word_ops_nth_size word_size)
 
 lemma nth_bounded:
   "\<lbrakk>bit (x :: 'a :: len word) n; x < 2 ^ m; m \<le> len_of TYPE ('a)\<rbrakk> \<Longrightarrow> n < m"
   apply (rule ccontr)
   apply (auto simp add: not_less)
   apply (meson bit_imp_le_length bit_uint_iff less_2p_is_upper_bits_unset test_bit_bin)
   done
 
 lemma and_neq_0_is_nth:
   \<open>x AND y \<noteq> 0 \<longleftrightarrow> bit x n\<close> if \<open>y = 2 ^ n\<close> for x y :: \<open>'a::len word\<close>
   apply (simp add: bit_eq_iff bit_simps)
   using that apply (simp add: bit_simps not_le)
   apply transfer
   apply auto
   done
 
 lemma nth_is_and_neq_0:
   "bit (x::'a::len word) n = (x AND 2 ^ n \<noteq> 0)"
   by (subst and_neq_0_is_nth; rule refl)
 
 lemma max_word_not_less [simp]:
    "\<not> - 1 < x" for x :: \<open>'a::len word\<close>
   by (fact word_order.extremum_strict)
 
 lemma bit_twiddle_min:
   "(y::'a::len word) XOR (((x::'a::len word) XOR y) AND (if x < y then -1 else 0)) = min x y"
   by (rule bit_eqI) (auto simp add: bit_simps)
 
 lemma bit_twiddle_max:
   "(x::'a::len word) XOR (((x::'a::len word) XOR y) AND (if x < y then -1 else 0)) = max x y"
   by (rule bit_eqI) (auto simp add: bit_simps max_def)
 
 lemma swap_with_xor:
   "\<lbrakk>(x::'a::len word) = a XOR b; y = b XOR x; z = x XOR y\<rbrakk> \<Longrightarrow> z = b \<and> y = a"
   by (auto intro: bit_word_eqI simp add: bit_simps)
 
 lemma le_mask_imp_and_mask:
   "(x::'a::len word) \<le> mask n \<Longrightarrow> x AND mask n = x"
   by (metis and_mask_eq_iff_le_mask)
 
 lemma or_not_mask_nop:
   "((x::'a::len word) OR NOT (mask n)) AND mask n = x AND mask n"
   by (metis word_and_not word_ao_dist2 word_bw_comms(1) word_log_esimps(3))
 
 lemma mask_subsume:
   "\<lbrakk>n \<le> m\<rbrakk> \<Longrightarrow> ((x::'a::len word) OR y AND mask n) AND NOT (mask m) = x AND NOT (mask m)"
   by (rule bit_word_eqI) (auto simp add: bit_simps word_size)
 
 lemma and_mask_0_iff_le_mask:
   fixes w :: "'a::len word"
   shows "(w AND NOT(mask n) = 0) = (w \<le> mask n)"
   by (simp add: mask_eq_0_eq_x le_mask_imp_and_mask and_mask_eq_iff_le_mask)
 
 lemma mask_twice2:
   "n \<le> m \<Longrightarrow> ((x::'a::len word) AND mask m) AND mask n = x AND mask n"
   by (metis mask_twice min_def)
 
 lemma uint_2_id:
   "LENGTH('a) \<ge> 2 \<Longrightarrow> uint (2::('a::len) word) = 2"
   by simp
 
 lemma div_of_0_id[simp]:"(0::('a::len) word) div n = 0"
   by (simp add: word_div_def)
 
 lemma degenerate_word:"LENGTH('a) = 1 \<Longrightarrow> (x::('a::len) word) = 0 \<or> x = 1"
   by (metis One_nat_def less_irrefl_nat sint_1_cases)
 
 lemma div_by_0_word:"(x::('a::len) word) div 0 = 0"
   by (metis div_0 div_by_0 unat_0 word_arith_nat_defs(6) word_div_1)
 
 lemma div_less_dividend_word:"\<lbrakk>x \<noteq> 0; n \<noteq> 1\<rbrakk> \<Longrightarrow> (x::('a::len) word) div n < x"
   apply (cases \<open>n = 0\<close>)
    apply clarsimp
    apply (simp add:word_neq_0_conv)
   apply (subst word_arith_nat_div)
   apply (rule word_of_nat_less)
   apply (rule div_less_dividend)
   using unat_eq_zero word_unat_Rep_inject1 apply force
   apply (simp add:unat_gt_0)
   done
 
 lemma word_less_div:
   fixes x :: "('a::len) word"
     and y :: "('a::len) word"
   shows "x div y = 0 \<Longrightarrow> y = 0 \<or> x < y"
   apply (case_tac "y = 0", clarsimp+)
   by (metis One_nat_def Suc_le_mono le0 le_div_geq not_less unat_0 unat_div unat_gt_0 word_less_nat_alt zero_less_one)
 
 lemma not_degenerate_imp_2_neq_0:"LENGTH('a) > 1 \<Longrightarrow> (2::('a::len) word) \<noteq> 0"
   by (metis numerals(1) power_not_zero power_zero_numeral)
 
 lemma word_overflow:"(x::('a::len) word) + 1 > x \<or> x + 1 = 0"
   apply clarsimp
   by (metis diff_0 eq_diff_eq less_x_plus_1)
 
 lemma word_overflow_unat:"unat ((x::('a::len) word) + 1) = unat x + 1 \<or> x + 1 = 0"
   by (metis Suc_eq_plus1 add.commute unatSuc)
 
 lemma even_word_imp_odd_next:"even (unat (x::('a::len) word)) \<Longrightarrow> x + 1 = 0 \<or> odd (unat (x + 1))"
   apply (cut_tac x=x in word_overflow_unat)
   apply clarsimp
   done
 
 lemma odd_word_imp_even_next:"odd (unat (x::('a::len) word)) \<Longrightarrow> x + 1 = 0 \<or> even (unat (x + 1))"
   apply (cut_tac x=x in word_overflow_unat)
   apply clarsimp
   done
 
 lemma overflow_imp_lsb:"(x::('a::len) word) + 1 = 0 \<Longrightarrow> bit x 0"
   using even_plus_one_iff [of x] by simp
 
 lemma odd_iff_lsb:"odd (unat (x::('a::len) word)) = bit x 0"
   by transfer (simp add: even_nat_iff)
 
 lemma of_nat_neq_iff_word:
       "x mod 2 ^ LENGTH('a) \<noteq> y mod 2 ^ LENGTH('a) \<Longrightarrow>
          (((of_nat x)::('a::len) word) \<noteq> of_nat y) = (x \<noteq> y)"
   apply (rule iffI)
    apply (case_tac "x = y")
    apply (subst (asm) of_nat_eq_iff[symmetric])
    apply auto
   apply (case_tac "((of_nat x)::('a::len) word) = of_nat y")
   apply auto
    apply (metis unat_of_nat)
   done
 
 lemma lsb_this_or_next: "\<not> (bit ((x::('a::len) word) + 1) 0) \<Longrightarrow> bit x 0"
   by simp
 
 lemma mask_or_not_mask:
   "x AND mask n OR x AND NOT (mask n) = x"
   for x :: \<open>'a::len word\<close>
   apply (subst word_oa_dist, simp)
   apply (subst word_oa_dist2, simp)
   done
 
 lemma word_gr0_conv_Suc: "(m::'a::len word) > 0 \<Longrightarrow> \<exists>n. m = n + 1"
   by (metis add.commute add_minus_cancel)
 
 lemma revcast_down_us [OF refl]:
   "rc = revcast \<Longrightarrow> source_size rc = target_size rc + n \<Longrightarrow> rc w = ucast (signed_drop_bit n w)"
   for w :: "'a::len word"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps ac_simps)
   done
 
 lemma revcast_down_ss [OF refl]:
   "rc = revcast \<Longrightarrow> source_size rc = target_size rc + n \<Longrightarrow> rc w = scast (signed_drop_bit n w)"
   for w :: "'a::len word"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps ac_simps)
   done
 
 lemma revcast_down_uu [OF refl]:
   "rc = revcast \<Longrightarrow> source_size rc = target_size rc + n \<Longrightarrow> rc w = ucast (drop_bit n w)"
   for w :: "'a::len word"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps ac_simps)
   done
 
 lemma revcast_down_su [OF refl]:
   "rc = revcast \<Longrightarrow> source_size rc = target_size rc + n \<Longrightarrow> rc w = scast (drop_bit n w)"
   for w :: "'a::len word"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps ac_simps)
   done
 
 lemma cast_down_rev [OF refl]:
   "uc = ucast \<Longrightarrow> source_size uc = target_size uc + n \<Longrightarrow> uc w = revcast (push_bit n w)"
   for w :: "'a::len word"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps)
   done
 
 lemma revcast_up [OF refl]:
   "rc = revcast \<Longrightarrow> source_size rc + n = target_size rc \<Longrightarrow>
     rc w = push_bit n (ucast w :: 'a::len word)"
   apply (simp add: source_size_def target_size_def)
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps)
   apply auto
   apply (metis add.commute add_diff_cancel_right)
   apply (metis diff_add_inverse2 diff_diff_add)
   done
 
 lemmas rc1 = revcast_up [THEN
   revcast_rev_ucast [symmetric, THEN trans, THEN word_rev_gal, symmetric]]
 lemmas rc2 = revcast_down_uu [THEN
   revcast_rev_ucast [symmetric, THEN trans, THEN word_rev_gal, symmetric]]
 
 lemma word_ops_nth:
   fixes x y :: \<open>'a::len word\<close>
   shows
   word_or_nth:  "bit (x OR y) n = (bit x n \<or> bit y n)" and
   word_and_nth: "bit (x AND y) n = (bit x n \<and> bit y n)" and
   word_xor_nth: "bit (x XOR y) n = (bit x n \<noteq> bit y n)"
   by (simp_all add: bit_simps)
 
 lemma word_power_nonzero:
   "\<lbrakk> (x :: 'a::len word) < 2 ^ (LENGTH('a) - n); n < LENGTH('a); x \<noteq> 0 \<rbrakk>
   \<Longrightarrow> x * 2 ^ n \<noteq> 0"
   by (metis gr_implies_not0 mult_eq_0_iff nat_mult_power_less_eq numeral_2_eq_2
     p2_gt_0 unat_eq_zero unat_less_power unat_mult_lem unat_power_lower word_gt_a_gt_0 zero_less_Suc)
 
 lemma less_1_helper:
   "n \<le> m \<Longrightarrow> (n - 1 :: int) < m"
   by arith
 
 lemma div_power_helper:
   "\<lbrakk> x \<le> y; y < LENGTH('a) \<rbrakk> \<Longrightarrow> (2 ^ y - 1) div (2 ^ x :: 'a::len word) = 2 ^ (y - x) - 1"
   apply (simp flip: mask_eq_exp_minus_1 drop_bit_eq_div)
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps not_le)
   done
 
 lemma max_word_mask:
   "(- 1 :: 'a::len word) = mask LENGTH('a)"
   by (fact minus_1_eq_mask)
 
 lemmas mask_len_max = max_word_mask[symmetric]
 
 lemma mask_out_first_mask_some:
   "\<lbrakk> x AND NOT (mask n) = y; n \<le> m \<rbrakk> \<Longrightarrow> x AND NOT (mask m) = y AND NOT (mask m)"
   for x y :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps word_size)
 
 lemma mask_lower_twice:
   "n \<le> m \<Longrightarrow> (x AND NOT (mask n)) AND NOT (mask m) = x AND NOT (mask m)"
   for x :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps word_size)
 
 lemma mask_lower_twice2:
   "(a AND NOT (mask n)) AND NOT (mask m) = a AND NOT (mask (max n m))"
   for a :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma ucast_and_neg_mask:
   "ucast (x AND NOT (mask n)) = ucast x AND NOT (mask n)"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps dest: bit_imp_le_length)
   done
 
 lemma ucast_and_mask:
   "ucast (x AND mask n) = ucast x AND mask n"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps dest: bit_imp_le_length)
   done
 
 lemma ucast_mask_drop:
   "LENGTH('a :: len) \<le> n \<Longrightarrow> (ucast (x AND mask n) :: 'a word) = ucast x"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps dest: bit_imp_le_length)
   done
 
 lemma mask_exceed:
   "n \<ge> LENGTH('a) \<Longrightarrow> (x::'a::len word) AND NOT (mask n) = 0"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma word_add_no_overflow:"(x::'a::len word) < - 1 \<Longrightarrow> x < x + 1"
   using less_x_plus_1 order_less_le by blast
 
 lemma lt_plus_1_le_word:
   fixes x :: "'a::len word"
   assumes bound:"n < unat (maxBound::'a word)"
   shows "x < 1 + of_nat n = (x \<le> of_nat n)"
   by (metis add.commute bound max_word_max word_Suc_leq word_not_le word_of_nat_less)
 
 lemma unat_ucast_up_simp:
   fixes x :: "'a::len word"
   assumes "LENGTH('a) \<le> LENGTH('b)"
   shows "unat (ucast x :: 'b::len word) = unat x"
   apply (rule bit_eqI)
   using assms apply (auto simp add: bit_simps dest: bit_imp_le_length)
   done
 
 lemma unat_ucast_less_no_overflow:
   "\<lbrakk>n < 2 ^ LENGTH('a); unat f < n\<rbrakk> \<Longrightarrow> (f::('a::len) word) < of_nat n"
   by (erule (1)  order_le_less_trans[OF _ of_nat_mono_maybe,rotated]) simp
 
 lemma unat_ucast_less_no_overflow_simp:
   "n < 2 ^ LENGTH('a) \<Longrightarrow> (unat f < n) = ((f::('a::len) word) < of_nat n)"
   using unat_less_helper unat_ucast_less_no_overflow by blast
 
 lemma unat_ucast_no_overflow_le:
   assumes no_overflow: "unat b < (2 :: nat) ^ LENGTH('a)"
   and upward_cast: "LENGTH('a) < LENGTH('b)"
   shows "(ucast (f::'a::len word) < (b :: 'b :: len word)) = (unat f < unat b)"
 proof -
   have LR: "ucast f < b \<Longrightarrow> unat f < unat b"
     apply (rule unat_less_helper)
     apply (simp add:ucast_nat_def)
     apply (rule_tac 'b1 = 'b in  ucast_less_ucast[OF order.strict_implies_order, THEN iffD1])
      apply (rule upward_cast)
     apply (simp add: ucast_ucast_mask less_mask_eq word_less_nat_alt
                      unat_power_lower[OF upward_cast] no_overflow)
     done
   have RL: "unat f < unat b \<Longrightarrow> ucast f < b"
   proof-
     assume ineq: "unat f < unat b"
     have "ucast (f::'a::len word) < ((ucast (ucast b ::'a::len word)) :: 'b :: len word)"
       apply (simp add: ucast_less_ucast[OF order.strict_implies_order] upward_cast)
       apply (simp only: flip: ucast_nat_def)
       apply (rule unat_ucast_less_no_overflow[OF no_overflow ineq])
       done
     then show ?thesis
       apply (rule order_less_le_trans)
       apply (simp add:ucast_ucast_mask word_and_le2)
       done
   qed
   then show ?thesis by (simp add:RL LR iffI)
 qed
 
 lemmas ucast_up_mono = ucast_less_ucast[THEN iffD2]
 
 lemma minus_one_word:
   "(-1 :: 'a :: len word) = 2 ^ LENGTH('a) - 1"
   by simp
 
 lemma le_2p_upper_bits:
   "\<lbrakk> (p::'a::len word) \<le> 2^n - 1; n < LENGTH('a) \<rbrakk> \<Longrightarrow>
   \<forall>n'\<ge>n. n' < LENGTH('a) \<longrightarrow> \<not> bit p n'"
   by (subst upper_bits_unset_is_l2p; simp)
 
 lemma le2p_bits_unset:
   "p \<le> 2 ^ n - 1 \<Longrightarrow> \<forall>n'\<ge>n. n' < LENGTH('a) \<longrightarrow> \<not> bit (p::'a::len word) n'"
   using upper_bits_unset_is_l2p [where p=p]
   by (cases "n < LENGTH('a)") auto
 
 lemma complement_nth_w2p:
   shows "n' < LENGTH('a) \<Longrightarrow> bit (NOT (2 ^ n :: 'a::len word)) n' = (n' \<noteq> n)"
   by (fastforce simp: word_ops_nth_size word_size nth_w2p)
 
 lemma word_unat_and_lt:
   "unat x < n \<or> unat y < n \<Longrightarrow> unat (x AND y) < n"
   by (meson le_less_trans word_and_le1 word_and_le2 word_le_nat_alt)
 
 lemma word_unat_mask_lt:
   "m \<le> size w \<Longrightarrow> unat ((w::'a::len word) AND mask m) < 2 ^ m"
   by (rule word_unat_and_lt) (simp add: unat_mask word_size)
 
 lemma word_sless_sint_le:"x <s y \<Longrightarrow> sint x \<le> sint y - 1"
   by (metis word_sless_alt zle_diff1_eq)
 
 lemma upper_trivial:
   fixes x :: "'a::len word"
   shows "x \<noteq> 2 ^ LENGTH('a) - 1 \<Longrightarrow> x < 2 ^ LENGTH('a) - 1"
   by (simp add: less_le)
 
 lemma constraint_expand:
   fixes x :: "'a::len word"
   shows "x \<in> {y. lower \<le> y \<and> y \<le> upper} = (lower \<le> x \<and> x \<le> upper)"
   by (rule mem_Collect_eq)
 
 lemma card_map_elide:
   "card ((of_nat :: nat \<Rightarrow> 'a::len word) ` {0..<n}) = card {0..<n}"
   if "n \<le> CARD('a::len word)"
 proof -
   let ?of_nat = "of_nat :: nat \<Rightarrow> 'a word"
   have "inj_on ?of_nat {i. i < CARD('a word)}"
     by (rule inj_onI) (simp add: card_word of_nat_inj)
   moreover have "{0..<n} \<subseteq> {i. i < CARD('a word)}"
     using that by auto
   ultimately have "inj_on ?of_nat {0..<n}"
     by (rule inj_on_subset)
   then show ?thesis
     by (simp add: card_image)
 qed
 
 lemma card_map_elide2:
   "n \<le> CARD('a::len word) \<Longrightarrow> card ((of_nat::nat \<Rightarrow> 'a::len word) ` {0..<n}) = n"
   by (subst card_map_elide) clarsimp+
 
 lemma eq_ucast_ucast_eq:
   "LENGTH('b) \<le> LENGTH('a) \<Longrightarrow> x = ucast y \<Longrightarrow> ucast x = y"
   for x :: "'a::len word" and y :: "'b::len word"
   by transfer simp
 
 lemma le_ucast_ucast_le:
   "x \<le> ucast y \<Longrightarrow> ucast x \<le> y"
   for x :: "'a::len word" and y :: "'b::len word"
   by (smt le_unat_uoi linorder_not_less order_less_imp_le ucast_nat_def unat_arith_simps(1))
 
 lemma less_ucast_ucast_less:
   "LENGTH('b) \<le> LENGTH('a) \<Longrightarrow> x < ucast y \<Longrightarrow> ucast x < y"
   for x :: "'a::len word" and y :: "'b::len word"
   by (metis ucast_nat_def unat_mono unat_ucast_up_simp word_of_nat_less)
 
 lemma ucast_le_ucast:
   "LENGTH('a) \<le> LENGTH('b) \<Longrightarrow> (ucast x \<le> (ucast y::'b::len word)) = (x \<le> y)"
   for x :: "'a::len word"
   by (simp add: unat_arith_simps(1) unat_ucast_up_simp)
 
 lemmas ucast_up_mono_le = ucast_le_ucast[THEN iffD2]
 
 lemma ucast_or_distrib:
   fixes x :: "'a::len word"
   fixes y :: "'a::len word"
   shows "(ucast (x OR y) :: ('b::len) word) = ucast x OR ucast y"
   by (fact unsigned_or_eq)
 
 lemma word_exists_nth:
   "(w::'a::len word) \<noteq> 0 \<Longrightarrow> \<exists>i. bit w i"
   by (auto simp add: bit_eq_iff)
 
 lemma max_word_not_0 [simp]:
   "- 1 \<noteq> (0 :: 'a::len word)"
   by simp
 
 lemma unat_max_word_pos[simp]: "0 < unat (- 1 :: 'a::len word)"
   using unat_gt_0 [of \<open>- 1 :: 'a::len word\<close>] by simp
 
 
 (* Miscellaneous conditional injectivity rules. *)
 
 lemma mult_pow2_inj:
   assumes ws: "m + n \<le> LENGTH('a)"
   assumes le: "x \<le> mask m" "y \<le> mask m"
   assumes eq: "x * 2 ^ n = y * (2 ^ n::'a::len word)"
   shows "x = y"
 proof (rule bit_word_eqI)
   fix q
   assume \<open>q < LENGTH('a)\<close>
   from eq have \<open>push_bit n x = push_bit n y\<close>
     by (simp add: push_bit_eq_mult)
   moreover from le have \<open>take_bit m x = x\<close> \<open>take_bit m y = y\<close>
     by (simp_all add: less_eq_mask_iff_take_bit_eq_self)
   ultimately have \<open>push_bit n (take_bit m x) = push_bit n (take_bit m y)\<close>
     by simp_all
   with \<open>q < LENGTH('a)\<close> ws show \<open>bit x q \<longleftrightarrow> bit y q\<close>
     apply (simp add: push_bit_take_bit)
     unfolding bit_eq_iff
     apply (simp add: bit_simps not_le)
     apply (metis (full_types) \<open>take_bit m x = x\<close> \<open>take_bit m y = y\<close> add.commute add_diff_cancel_right' add_less_cancel_right bit_take_bit_iff le_add2 less_le_trans)
     done
 qed
 
 lemma word_of_nat_inj:
   assumes bounded: "x < 2 ^ LENGTH('a)" "y < 2 ^ LENGTH('a)"
   assumes of_nats: "of_nat x = (of_nat y :: 'a::len word)"
   shows "x = y"
   by (rule contrapos_pp[OF of_nats]; cases "x < y"; cases "y < x")
      (auto dest: bounded[THEN of_nat_mono_maybe])
 
 lemma word_of_int_bin_cat_eq_iff:
   "(word_of_int (concat_bit LENGTH('b) (uint b) (uint a))::'c::len word) =
   word_of_int (concat_bit LENGTH('b) (uint d) (uint c)) \<longleftrightarrow> b = d \<and> a = c"
   if "LENGTH('a) + LENGTH('b) \<le> LENGTH('c)"
   for a::"'a::len word" and b::"'b::len word"
 proof -
   from that show ?thesis
   using that concat_bit_eq_iff [of \<open>LENGTH('b)\<close> \<open>uint b\<close> \<open>uint a\<close> \<open>uint d\<close> \<open>uint c\<close>]
   apply (simp add: word_of_int_eq_iff take_bit_int_eq_self flip: word_eq_iff_unsigned)
   apply (simp add: concat_bit_def take_bit_int_eq_self bintr_uint take_bit_push_bit)
   done
 qed
 
 lemma word_cat_inj: "(word_cat a b::'c::len word) = word_cat c d \<longleftrightarrow> a = c \<and> b = d"
   if "LENGTH('a) + LENGTH('b) \<le> LENGTH('c)"
   for a::"'a::len word" and b::"'b::len word"
   using word_of_int_bin_cat_eq_iff [OF that, of b a d c]
   by (simp add: word_cat_eq' ac_simps)
 
 lemma p2_eq_1: "2 ^ n = (1::'a::len word) \<longleftrightarrow> n = 0"
 proof -
   have "2 ^ n = (1::'a word) \<Longrightarrow> n = 0"
     by (metis One_nat_def not_less one_less_numeral_iff p2_eq_0 p2_gt_0 power_0 power_0
         power_inject_exp semiring_norm(76) unat_power_lower zero_neq_one)
   then show ?thesis by auto
 qed
 
 end
 
+lemmas word_div_less = div_word_less
+
+(* FIXME: move to Word distribution? *)
+lemma bin_nth_minus_Bit0[simp]:
+  "0 < n \<Longrightarrow> bit (numeral (num.Bit0 w) :: int) n = bit (numeral w :: int) (n - 1)"
+  by (cases n; simp)
+
+lemma bin_nth_minus_Bit1[simp]:
+  "0 < n \<Longrightarrow> bit (numeral (num.Bit1 w) :: int) n = bit (numeral w :: int) (n - 1)"
+  by (cases n; simp)
+
+lemma word_mod_by_0: "k mod (0::'a::len word) = k"
+  by (simp add: word_arith_nat_mod)
+
 end
diff --git a/thys/Word_Lib/More_Word_Operations.thy b/thys/Word_Lib/More_Word_Operations.thy
--- a/thys/Word_Lib/More_Word_Operations.thy
+++ b/thys/Word_Lib/More_Word_Operations.thy
@@ -1,1064 +1,1015 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section \<open>Misc word operations\<close>
 
 theory More_Word_Operations
   imports
     "HOL-Library.Word"
     Aligned
     Reversed_Bit_Lists
     More_Misc
     Signed_Words
     Word_Lemmas
+    Word_EqI
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 definition
   ptr_add :: "'a :: len word \<Rightarrow> nat \<Rightarrow> 'a word" where
   "ptr_add ptr n \<equiv> ptr + of_nat n"
 
 definition
   alignUp :: "'a::len word \<Rightarrow> nat \<Rightarrow> 'a word" where
  "alignUp x n \<equiv> x + 2 ^ n - 1 AND NOT (2 ^ n - 1)"
 
 lemma alignUp_unfold:
   \<open>alignUp w n = (w + mask n) AND NOT (mask n)\<close>
   by (simp add: alignUp_def mask_eq_exp_minus_1 add_mask_fold)
 
 (* standard notation for blocks of 2^n-1 words, usually aligned;
    abbreviation so it simplifies directly *)
 abbreviation mask_range :: "'a::len word \<Rightarrow> nat \<Rightarrow> 'a word set" where
   "mask_range p n \<equiv> {p .. p + mask n}"
 
 definition
   w2byte :: "'a :: len word \<Rightarrow> 8 word" where
   "w2byte \<equiv> ucast"
 
 (* Count leading zeros  *)
 definition
   word_clz :: "'a::len word \<Rightarrow> nat"
 where
   "word_clz w \<equiv> length (takeWhile Not (to_bl w))"
 
 (* Count trailing zeros  *)
 definition
   word_ctz :: "'a::len word \<Rightarrow> nat"
 where
   "word_ctz w \<equiv> length (takeWhile Not (rev (to_bl w)))"
 
 lemma word_ctz_unfold:
   \<open>word_ctz w = length (takeWhile (Not \<circ> bit w) [0..<LENGTH('a)])\<close> for w :: \<open>'a::len word\<close>
   by (simp add: word_ctz_def rev_to_bl_eq takeWhile_map)
 
 lemma word_ctz_unfold':
   \<open>word_ctz w = Min (insert LENGTH('a) {n. bit w n})\<close> for w :: \<open>'a::len word\<close>
 proof (cases \<open>\<exists>n. bit w n\<close>)
   case True
   then obtain n where \<open>bit w n\<close> ..
   from \<open>bit w n\<close> show ?thesis
     apply (simp add: word_ctz_unfold)
     apply (subst Min_eq_length_takeWhile [symmetric])
       apply (auto simp add: bit_imp_le_length)
     apply (subst Min_insert)
       apply auto
     apply (subst min.absorb2)
      apply (subst Min_le_iff)
        apply auto
     apply (meson bit_imp_le_length order_less_le)
     done
 next
   case False
   then have \<open>bit w = bot\<close>
     by auto
   then have \<open>word_ctz w = LENGTH('a)\<close>
     by (simp add: word_ctz_def rev_to_bl_eq bot_fun_def map_replicate_const)
   with \<open>bit w = bot\<close> show ?thesis
     by simp
 qed
 
 lemma word_ctz_le:
   "word_ctz (w :: ('a::len word)) \<le> LENGTH('a)"
   apply (clarsimp simp: word_ctz_def)
   using length_takeWhile_le apply (rule order_trans)
   apply simp
   done
 
 lemma word_ctz_less:
   "w \<noteq> 0 \<Longrightarrow> word_ctz (w :: ('a::len word)) < LENGTH('a)"
   apply (clarsimp simp: word_ctz_def eq_zero_set_bl)
   using length_takeWhile_less apply (rule less_le_trans)
   apply auto
   done
 
 lemma take_bit_word_ctz_eq [simp]:
   \<open>take_bit LENGTH('a) (word_ctz w) = word_ctz w\<close>
   for w :: \<open>'a::len word\<close>
   apply (simp add: take_bit_nat_eq_self_iff word_ctz_def to_bl_unfold)
   using length_takeWhile_le apply (rule le_less_trans)
   apply simp
   done
 
 lemma word_ctz_not_minus_1:
   \<open>word_of_nat (word_ctz (w :: 'a :: len word)) \<noteq> (- 1 :: 'a::len word)\<close> if \<open>1 < LENGTH('a)\<close>
 proof -
   note word_ctz_le
   also from that have \<open>LENGTH('a) < mask LENGTH('a)\<close>
     by (simp add: less_mask)
   finally have \<open>word_ctz w < mask LENGTH('a)\<close> .
   then have \<open>word_of_nat (word_ctz w) < (word_of_nat (mask LENGTH('a)) :: 'a word)\<close>
     by (simp add: of_nat_word_less_iff)
   also have \<open>\<dots> = - 1\<close>
     by (rule bit_word_eqI) (simp add: bit_simps)
   finally show ?thesis
     by simp
 qed
 
 lemma unat_of_nat_ctz_mw:
   "unat (of_nat (word_ctz (w :: 'a :: len word)) :: 'a :: len word) = word_ctz w"
   by (simp add: unsigned_of_nat)
 
 lemma unat_of_nat_ctz_smw:
   "unat (of_nat (word_ctz (w :: 'a :: len word)) :: 'a :: len signed word) = word_ctz w"
   by (simp add: unsigned_of_nat)
 
 definition
   word_log2 :: "'a::len word \<Rightarrow> nat"
 where
   "word_log2 (w::'a::len word) \<equiv> size w - 1 - word_clz w"
 
 (* Bit population count. Equivalent of __builtin_popcount. *)
 definition
   pop_count :: "('a::len) word \<Rightarrow> nat"
 where
   "pop_count w \<equiv> length (filter id (to_bl w))"
 
 (* Sign extension from bit n *)
 definition
   sign_extend :: "nat \<Rightarrow> 'a::len word \<Rightarrow> 'a word"
 where
   "sign_extend n w \<equiv> if bit w n then w OR NOT (mask n) else w AND mask n"
 
 lemma sign_extend_eq_signed_take_bit:
   \<open>sign_extend = signed_take_bit\<close>
 proof (rule ext)+
   fix n and w :: \<open>'a::len word\<close>
   show \<open>sign_extend n w = signed_take_bit n w\<close>
   proof (rule bit_word_eqI)
     fix q
     assume \<open>q < LENGTH('a)\<close>
     then show \<open>bit (sign_extend n w) q \<longleftrightarrow> bit (signed_take_bit n w) q\<close>
       by (auto simp add: bit_signed_take_bit_iff
         sign_extend_def bit_and_iff bit_or_iff bit_not_iff bit_mask_iff not_less
         exp_eq_0_imp_not_bit not_le min_def)
   qed
 qed
 
 definition
   sign_extended :: "nat \<Rightarrow> 'a::len word \<Rightarrow> bool"
 where
   "sign_extended n w \<equiv> \<forall>i. n < i \<longrightarrow> i < size w \<longrightarrow> bit w i = bit w n"
 
 lemma ptr_add_0 [simp]:
   "ptr_add ref 0 = ref "
   unfolding ptr_add_def by simp
 
 lemma pop_count_0[simp]:
   "pop_count 0 = 0"
   by (clarsimp simp:pop_count_def)
 
 lemma pop_count_1[simp]:
   "pop_count 1 = 1"
   by (clarsimp simp:pop_count_def to_bl_1)
 
 lemma pop_count_0_imp_0:
   "(pop_count w = 0) = (w = 0)"
   apply (rule iffI)
    apply (clarsimp simp:pop_count_def)
    apply (subst (asm) filter_empty_conv)
    apply (clarsimp simp:eq_zero_set_bl)
    apply fast
   apply simp
   done
 
 lemma word_log2_zero_eq [simp]:
   \<open>word_log2 0 = 0\<close>
   by (simp add: word_log2_def word_clz_def word_size)
 
 lemma word_log2_unfold:
   \<open>word_log2 w = (if w = 0 then 0 else Max {n. bit w n})\<close>
   for w :: \<open>'a::len word\<close>
 proof (cases \<open>w = 0\<close>)
   case True
   then show ?thesis
     by simp
 next
   case False
   then obtain r where \<open>bit w r\<close>
     by (auto simp add: bit_eq_iff)
   then have \<open>Max {m. bit w m} = LENGTH('a) - Suc (length
     (takeWhile (Not \<circ> bit w) (rev [0..<LENGTH('a)])))\<close>
     by (subst Max_eq_length_takeWhile [of _ \<open>LENGTH('a)\<close>])
       (auto simp add: bit_imp_le_length)
   then have \<open>word_log2 w = Max {x. bit w x}\<close>
     by (simp add: word_log2_def word_clz_def word_size to_bl_unfold rev_map takeWhile_map)
   with \<open>w \<noteq> 0\<close> show ?thesis
     by simp
 qed
 
 lemma word_log2_eqI:
   \<open>word_log2 w = n\<close>
   if \<open>w \<noteq> 0\<close> \<open>bit w n\<close> \<open>\<And>m. bit w m \<Longrightarrow> m \<le> n\<close>
   for w :: \<open>'a::len word\<close>
 proof -
   from \<open>w \<noteq> 0\<close> have \<open>word_log2 w = Max {n. bit w n}\<close>
     by (simp add: word_log2_unfold)
   also have \<open>Max {n. bit w n} = n\<close>
     using that by (auto intro: Max_eqI)
   finally show ?thesis .
 qed
 
 lemma bit_word_log2:
   \<open>bit w (word_log2 w)\<close> if \<open>w \<noteq> 0\<close>
 proof -
   from \<open>w \<noteq> 0\<close> have \<open>\<exists>r. bit w r\<close>
     by (auto intro: bit_eqI)
   then obtain r where \<open>bit w r\<close> ..
   from \<open>w \<noteq> 0\<close> have \<open>word_log2 w = Max {n. bit w n}\<close>
     by (simp add: word_log2_unfold)
   also have \<open>Max {n. bit w n} \<in> {n. bit w n}\<close>
     using \<open>bit w r\<close> by (subst Max_in) auto
   finally show ?thesis
     by simp
 qed
 
 lemma word_log2_maximum:
   \<open>n \<le> word_log2 w\<close> if \<open>bit w n\<close>
 proof -
   have \<open>n \<le> Max {n. bit w n}\<close>
     using that by (auto intro: Max_ge)
   also from that have \<open>w \<noteq> 0\<close>
     by force
   then have \<open>Max {n. bit w n} = word_log2 w\<close>
     by (simp add: word_log2_unfold)
   finally show ?thesis .
 qed
 
 lemma word_log2_nth_same:
   "w \<noteq> 0 \<Longrightarrow> bit w (word_log2 w)"
   by (drule bit_word_log2) simp
 
 lemma word_log2_nth_not_set:
   "\<lbrakk> word_log2 w < i ; i < size w \<rbrakk> \<Longrightarrow> \<not> bit w i"
   using word_log2_maximum [of w i] by auto
 
 lemma word_log2_highest:
   assumes a: "bit w i"
   shows "i \<le> word_log2 w"
   using a by (simp add: word_log2_maximum)
 
 lemma word_log2_max:
   "word_log2 w < size w"
   apply (cases \<open>w = 0\<close>)
    apply (simp_all add: word_size)
   apply (drule bit_word_log2)
   apply (fact bit_imp_le_length)
   done
 
 lemma word_clz_0[simp]:
   "word_clz (0::'a::len word) = LENGTH('a)"
   unfolding word_clz_def by simp
 
 lemma word_clz_minus_one[simp]:
   "word_clz (-1::'a::len word) = 0"
   unfolding word_clz_def by simp
 
 lemma is_aligned_alignUp[simp]:
   "is_aligned (alignUp p n) n"
   by (simp add: alignUp_def is_aligned_mask mask_eq_decr_exp word_bw_assocs)
 
 lemma alignUp_le[simp]:
   "alignUp p n \<le> p + 2 ^ n - 1"
   unfolding alignUp_def by (rule word_and_le2)
 
 lemma alignUp_idem:
   fixes a :: "'a::len word"
   assumes "is_aligned a n" "n < LENGTH('a)"
   shows "alignUp a n = a"
   using assms unfolding alignUp_def
   by (metis add_cancel_right_right add_diff_eq and_mask_eq_iff_le_mask mask_eq_decr_exp mask_out_add_aligned order_refl word_plus_and_or_coroll2)
 
 lemma alignUp_not_aligned_eq:
   fixes a :: "'a :: len word"
   assumes al: "\<not> is_aligned a n"
   and     sz: "n < LENGTH('a)"
   shows   "alignUp a n = (a div 2 ^ n + 1) * 2 ^ n"
 proof -
   have anz: "a mod 2 ^ n \<noteq> 0"
     by (rule not_aligned_mod_nz) fact+
 
   then have um: "unat (a mod 2 ^ n - 1) div 2 ^ n = 0" using sz
     by (meson Euclidean_Division.div_eq_0_iff le_m1_iff_lt measure_unat order_less_trans
               unat_less_power word_less_sub_le word_mod_less_divisor)
 
   have "a + 2 ^ n - 1 = (a div 2 ^ n) * 2 ^ n + (a mod 2 ^ n) + 2 ^ n - 1"
     by (simp add: word_mod_div_equality)
   also have "\<dots> = (a mod 2 ^ n - 1) + (a div 2 ^ n + 1) * 2 ^ n"
     by (simp add: field_simps)
   finally show "alignUp a n = (a div 2 ^ n + 1) * 2 ^ n" using sz
     unfolding alignUp_def
     apply (subst mask_eq_decr_exp [symmetric])
     apply (erule ssubst)
     apply (subst neg_mask_is_div)
     apply (simp add: word_arith_nat_div)
     apply (subst unat_word_ariths(1) unat_word_ariths(2))+
     apply (subst uno_simps)
     apply (subst unat_1)
     apply (subst mod_add_right_eq)
     apply simp
     apply (subst power_mod_div)
     apply (subst div_mult_self1)
      apply simp
     apply (subst um)
     apply simp
     apply (subst mod_mod_power)
     apply simp
     apply (subst word_unat_power, subst Abs_fnat_hom_mult)
     apply (subst mult_mod_left)
     apply (subst power_add [symmetric])
     apply simp
     apply (subst Abs_fnat_hom_1)
     apply (subst Abs_fnat_hom_add)
     apply (subst word_unat_power, subst Abs_fnat_hom_mult)
     apply (subst word_unat.Rep_inverse[symmetric], subst Abs_fnat_hom_mult)
     apply simp
     done
 qed
 
 lemma alignUp_ge:
   fixes a :: "'a :: len word"
   assumes sz: "n < LENGTH('a)"
   and nowrap: "alignUp a n \<noteq> 0"
   shows "a \<le> alignUp a n"
 proof (cases "is_aligned a n")
   case True
   then show ?thesis using sz
     by (subst alignUp_idem, simp_all)
 next
   case False
 
   have lt0: "unat a div 2 ^ n < 2 ^ (LENGTH('a) - n)" using sz
     by (metis le_add_diff_inverse2 less_mult_imp_div_less order_less_imp_le power_add unsigned_less)
 
   have"2 ^ n * (unat a div 2 ^ n + 1) \<le> 2 ^ LENGTH('a)" using sz
     by (metis One_nat_def Suc_leI add.right_neutral add_Suc_right lt0 nat_le_power_trans nat_less_le)
   moreover have "2 ^ n * (unat a div 2 ^ n + 1) \<noteq> 2 ^ LENGTH('a)" using nowrap sz
     apply -
     apply (erule contrapos_nn)
     apply (subst alignUp_not_aligned_eq [OF False sz])
     apply (subst unat_arith_simps)
     apply (subst unat_word_ariths)
     apply (subst unat_word_ariths)
     apply simp
     apply (subst mult_mod_left)
     apply (simp add: unat_div field_simps power_add[symmetric] mod_mod_power)
     done
   ultimately have lt: "2 ^ n * (unat a div 2 ^ n + 1) < 2 ^ LENGTH('a)" by simp
 
   have "a = a div 2 ^ n * 2 ^ n + a mod 2 ^ n" by (rule word_mod_div_equality [symmetric])
   also have "\<dots> < (a div 2 ^ n + 1) * 2 ^ n" using sz lt
     apply (simp add: field_simps)
     apply (rule word_add_less_mono1)
     apply (rule word_mod_less_divisor)
     apply (simp add: word_less_nat_alt)
     apply (subst unat_word_ariths)
     apply (simp add: unat_div)
     done
   also have "\<dots> =  alignUp a n"
     by (rule alignUp_not_aligned_eq [symmetric]) fact+
   finally show ?thesis by (rule order_less_imp_le)
 qed
 
 lemma alignUp_le_greater_al:
   fixes x :: "'a :: len word"
   assumes le: "a \<le> x"
   and     sz: "n < LENGTH('a)"
   and     al: "is_aligned x n"
   shows   "alignUp a n \<le> x"
 proof (cases "is_aligned a n")
   case True
   then show ?thesis using sz le by (simp add: alignUp_idem)
 next
   case False
 
   then have anz: "a mod 2 ^ n \<noteq> 0"
     by (rule not_aligned_mod_nz)
 
   from al obtain k where xk: "x = 2 ^ n * of_nat k" and kv: "k < 2 ^ (LENGTH('a) - n)"
     by (auto elim!: is_alignedE)
 
   then have kn: "unat (of_nat k :: 'a word) * unat ((2::'a word) ^ n) < 2 ^ LENGTH('a)"
     using sz
     apply (subst unat_of_nat_eq)
      apply (erule order_less_le_trans)
      apply simp
     apply (subst mult.commute)
     apply simp
     apply (rule nat_less_power_trans)
      apply simp
     apply simp
     done
 
   have au: "alignUp a n = (a div 2 ^ n + 1) * 2 ^ n"
     by (rule alignUp_not_aligned_eq) fact+
   also have "\<dots> \<le> of_nat k * 2 ^ n"
   proof (rule word_mult_le_mono1 [OF inc_le _ kn])
     show "a div 2 ^ n < of_nat k" using kv xk le sz anz
       by (simp add: alignUp_div_helper)
 
     show "(0:: 'a word) < 2 ^ n" using sz by (simp add: p2_gt_0 sz)
   qed
 
   finally show ?thesis using xk by (simp add: field_simps)
 qed
 
 lemma alignUp_is_aligned_nz:
   fixes a :: "'a :: len word"
   assumes al: "is_aligned x n"
   and     sz: "n < LENGTH('a)"
   and     ax: "a \<le> x"
   and     az: "a \<noteq> 0"
   shows   "alignUp (a::'a :: len word) n \<noteq> 0"
 proof (cases "is_aligned a n")
   case True
   then have "alignUp a n = a" using sz by (simp add: alignUp_idem)
   then show ?thesis using az by simp
 next
   case False
   then have anz: "a mod 2 ^ n \<noteq> 0"
     by (rule not_aligned_mod_nz)
 
   {
     assume asm: "alignUp a n = 0"
 
     have lt0: "unat a div 2 ^ n < 2 ^ (LENGTH('a) - n)" using sz
       by (metis le_add_diff_inverse2 less_mult_imp_div_less order_less_imp_le power_add unsigned_less)
 
     have leq: "2 ^ n * (unat a div 2 ^ n + 1) \<le> 2 ^ LENGTH('a)" using sz
       by (metis One_nat_def Suc_leI add.right_neutral add_Suc_right lt0 nat_le_power_trans
                 order_less_imp_le)
 
     from al obtain k where  kv: "k < 2 ^ (LENGTH('a) - n)" and xk: "x = 2 ^ n * of_nat k"
       by (auto elim!: is_alignedE)
 
     then have "a div 2 ^ n < of_nat k" using ax sz anz
       by (rule alignUp_div_helper)
 
     then have r: "unat a div 2 ^ n < k" using sz
       by (simp flip: drop_bit_eq_div unat_drop_bit_eq) (metis leI le_unat_uoi unat_mono)
 
     have "alignUp a n = (a div 2 ^ n + 1) * 2 ^ n"
       by (rule alignUp_not_aligned_eq) fact+
 
     then have "\<dots> = 0" using asm by simp
     then have "2 ^ LENGTH('a) dvd 2 ^ n * (unat a div 2 ^ n + 1)"
       using sz by (simp add: unat_arith_simps ac_simps)
                   (simp add: unat_word_ariths mod_simps mod_eq_0_iff_dvd)
     with leq have "2 ^ n * (unat a div 2 ^ n + 1) = 2 ^ LENGTH('a)"
       by (force elim!: le_SucE)
     then have "unat a div 2 ^ n = 2 ^ LENGTH('a) div 2 ^ n - 1"
       by (metis (no_types, opaque_lifting) Groups.add_ac(2) add.right_neutral
                 add_diff_cancel_left' div_le_dividend div_mult_self4 gr_implies_not0
                 le_neq_implies_less power_eq_0_iff zero_neq_numeral)
     then have "unat a div 2 ^ n = 2 ^ (LENGTH('a) - n) - 1"
       using sz by (simp add: power_sub)
     then have "2 ^ (LENGTH('a) - n) - 1 < k" using r
       by simp
     then have False using kv by simp
   } then show ?thesis by clarsimp
 qed
 
 lemma alignUp_ar_helper:
   fixes a :: "'a :: len word"
   assumes al: "is_aligned x n"
   and     sz: "n < LENGTH('a)"
   and    sub: "{x..x + 2 ^ n - 1} \<subseteq> {a..b}"
   and    anz: "a \<noteq> 0"
   shows "a \<le> alignUp a n \<and> alignUp a n + 2 ^ n - 1 \<le> b"
 proof
   from al have xl: "x \<le> x + 2 ^ n - 1" by (simp add: is_aligned_no_overflow)
 
   from xl sub have ax: "a \<le> x"
     by auto
 
   show "a \<le> alignUp a n"
   proof (rule alignUp_ge)
     show "alignUp a n \<noteq> 0" using al sz ax anz
       by (rule alignUp_is_aligned_nz)
   qed fact+
 
   show "alignUp a n + 2 ^ n - 1 \<le> b"
   proof (rule order_trans)
     from xl show tp: "x + 2 ^ n - 1 \<le> b" using sub
       by auto
 
     from ax have "alignUp a n \<le> x"
       by (rule alignUp_le_greater_al) fact+
     then have "alignUp a n + (2 ^ n - 1) \<le> x + (2 ^ n - 1)"
       using xl al is_aligned_no_overflow' olen_add_eqv word_plus_mcs_3 by blast
     then show "alignUp a n + 2 ^ n - 1 \<le> x + 2 ^ n - 1"
       by (simp add: field_simps)
   qed
 qed
 
 lemma alignUp_def2:
   "alignUp a sz = a + 2 ^ sz - 1 AND NOT (mask sz)"
   by (simp add: alignUp_def flip: mask_eq_decr_exp)
 
 lemma alignUp_def3:
   "alignUp a sz = 2^ sz + (a - 1 AND NOT (mask sz))"
   by (simp add: alignUp_def2 is_aligned_triv field_simps mask_out_add_aligned)
 
 lemma  alignUp_plus:
   "is_aligned w us \<Longrightarrow> alignUp (w + a) us  = w + alignUp a us"
   by (clarsimp simp: alignUp_def2 mask_out_add_aligned field_simps)
 
 lemma alignUp_distance:
   "alignUp (q :: 'a :: len word) sz - q \<le> mask sz"
   by (metis (no_types) add.commute add_diff_cancel_left alignUp_def2 diff_add_cancel
                        mask_2pm1 subtract_mask(2) word_and_le1 word_sub_le_iff)
 
 lemma is_aligned_diff_neg_mask:
   "is_aligned p sz \<Longrightarrow> (p - q AND NOT (mask sz)) = (p - ((alignUp q sz) AND NOT (mask sz)))"
   apply (clarsimp simp only:word_and_le2 diff_conv_add_uminus)
   apply (subst mask_out_add_aligned[symmetric]; simp)
   apply (simp add: eq_neg_iff_add_eq_0)
   apply (subst add.commute)
   apply (simp add: alignUp_distance is_aligned_neg_mask_eq mask_out_add_aligned and_mask_eq_iff_le_mask flip: mask_eq_x_eq_0)
   done
 
 lemma word_clz_max:
   "word_clz w \<le> size (w::'a::len word)"
   unfolding word_clz_def
   by (metis length_takeWhile_le word_size_bl)
 
 lemma word_clz_nonzero_max:
   fixes w :: "'a::len word"
   assumes nz: "w \<noteq> 0"
   shows "word_clz w < size (w::'a::len word)"
 proof -
   {
     assume a: "word_clz w = size (w::'a::len word)"
     hence "length (takeWhile Not (to_bl w)) = length (to_bl w)"
       by (simp add: word_clz_def word_size)
     hence allj: "\<forall>j\<in>set(to_bl w). \<not> j"
       by (metis a length_takeWhile_less less_irrefl_nat word_clz_def)
     hence "to_bl w = replicate (length (to_bl w)) False"
       using eq_zero_set_bl nz by fastforce
     hence "w = 0"
       by (metis to_bl_0 word_bl.Rep_eqD word_bl_Rep')
     with nz have False by simp
   }
   thus ?thesis using word_clz_max
     by (fastforce intro: le_neq_trans)
 qed
 
 (* Sign extension from bit n. *)
 
 lemma bin_sign_extend_iff [bit_simps]:
   \<open>bit (sign_extend e w) i \<longleftrightarrow> bit w (min e i)\<close>
   if \<open>i < LENGTH('a)\<close> for w :: \<open>'a::len word\<close>
   using that by (simp add: sign_extend_def bit_simps min_def)
 
 lemma sign_extend_bitwise_if:
   "i < size w \<Longrightarrow> bit (sign_extend e w) i \<longleftrightarrow> (if i < e then bit w i else bit w e)"
   by (simp add: word_size bit_simps)
 
 lemma sign_extend_bitwise_if'  [word_eqI_simps]:
   \<open>i < LENGTH('a) \<Longrightarrow> bit (sign_extend e w) i \<longleftrightarrow> (if i < e then bit w i else bit w e)\<close>
   for w :: \<open>'a::len word\<close>
   using sign_extend_bitwise_if [of i w e] by (simp add: word_size)
 
 lemma sign_extend_bitwise_disj:
   "i < size w \<Longrightarrow> bit (sign_extend e w) i \<longleftrightarrow> i \<le> e \<and> bit w i \<or> e \<le> i \<and> bit w e"
   by (auto simp: sign_extend_bitwise_if)
 
 lemma sign_extend_bitwise_cases:
   "i < size w \<Longrightarrow> bit (sign_extend e w) i \<longleftrightarrow> (i \<le> e \<longrightarrow> bit w i) \<and> (e \<le> i \<longrightarrow> bit w e)"
   by (auto simp: sign_extend_bitwise_if)
 
 lemmas sign_extend_bitwise_disj' = sign_extend_bitwise_disj[simplified word_size]
 lemmas sign_extend_bitwise_cases' = sign_extend_bitwise_cases[simplified word_size]
 
 (* Often, it is easier to reason about an operation which does not overwrite
    the bit which determines which mask operation to apply. *)
 lemma sign_extend_def':
   "sign_extend n w = (if bit w n then w OR NOT (mask (Suc n)) else w AND mask (Suc n))"
   by (rule bit_word_eqI) (auto simp add: bit_simps sign_extend_eq_signed_take_bit min_def less_Suc_eq_le)
 
 lemma sign_extended_sign_extend:
   "sign_extended n (sign_extend n w)"
   by (clarsimp simp: sign_extended_def word_size sign_extend_bitwise_if)
 
 lemma sign_extended_iff_sign_extend:
   "sign_extended n w \<longleftrightarrow> sign_extend n w = w"
   apply auto
    apply (auto simp add: bit_eq_iff)
     apply (simp_all add: bit_simps sign_extend_eq_signed_take_bit not_le min_def sign_extended_def word_size split: if_splits)
   using le_imp_less_or_eq apply auto
   done
 
 lemma sign_extended_weaken:
   "sign_extended n w \<Longrightarrow> n \<le> m \<Longrightarrow> sign_extended m w"
   unfolding sign_extended_def by (cases "n < m") auto
 
 lemma sign_extend_sign_extend_eq:
   "sign_extend m (sign_extend n w) = sign_extend (min m n) w"
   by (rule bit_word_eqI) (simp add: sign_extend_eq_signed_take_bit bit_simps)
 
 lemma sign_extended_high_bits:
   "\<lbrakk> sign_extended e p; j < size p; e \<le> i; i < j \<rbrakk> \<Longrightarrow> bit p i = bit p j"
   by (drule (1) sign_extended_weaken; simp add: sign_extended_def)
 
 lemma sign_extend_eq:
   "w AND mask (Suc n) = v AND mask (Suc n) \<Longrightarrow> sign_extend n w = sign_extend n v"
   by (simp flip: take_bit_eq_mask add: sign_extend_eq_signed_take_bit signed_take_bit_eq_iff_take_bit_eq)
 
 lemma sign_extended_add:
   assumes p: "is_aligned p n"
   assumes f: "f < 2 ^ n"
   assumes e: "n \<le> e"
   assumes "sign_extended e p"
   shows "sign_extended e (p + f)"
 proof (cases "e < size p")
   case True
   note and_or = is_aligned_add_or[OF p f]
   have "\<not> bit f e"
     using True e less_2p_is_upper_bits_unset[THEN iffD1, OF f]
     by (fastforce simp: word_size)
   hence i: "bit (p + f) e = bit p e"
     by (simp add: and_or bit_simps)
   have fm: "f AND mask e = f"
     by (fastforce intro: subst[where P="\<lambda>f. f AND mask e = f", OF less_mask_eq[OF f]]
                   simp: mask_twice e)
   show ?thesis
     using assms
      apply (simp add: sign_extended_iff_sign_extend sign_extend_def i)
      apply (simp add: and_or word_bw_comms[of p f])
      apply (clarsimp simp: word_ao_dist fm word_bw_assocs split: if_splits)
     done
 next
   case False thus ?thesis
     by (simp add: sign_extended_def word_size)
 qed
 
 lemma sign_extended_neq_mask:
   "\<lbrakk>sign_extended n ptr; m \<le> n\<rbrakk> \<Longrightarrow> sign_extended n (ptr AND NOT (mask m))"
   by (fastforce simp: sign_extended_def word_size neg_mask_test_bit bit_simps)
 
 definition
   "limited_and (x :: 'a :: len word) y \<longleftrightarrow> (x AND y = x)"
 
 lemma limited_and_eq_0:
   "\<lbrakk> limited_and x z; y AND NOT z = y \<rbrakk> \<Longrightarrow> x AND y = 0"
   unfolding limited_and_def
   apply (subst arg_cong2[where f="(AND)"])
     apply (erule sym)+
   apply (simp(no_asm) add: word_bw_assocs word_bw_comms word_bw_lcs)
   done
 
 lemma limited_and_eq_id:
   "\<lbrakk> limited_and x z; y AND z = z \<rbrakk> \<Longrightarrow> x AND y = x"
   unfolding limited_and_def
   by (erule subst, fastforce simp: word_bw_lcs word_bw_assocs word_bw_comms)
 
 lemma lshift_limited_and:
   "limited_and x z \<Longrightarrow> limited_and (x << n) (z << n)"
-  unfolding limited_and_def
-  by (metis push_bit_and)
+  using push_bit_and [of n x z] by (simp add: limited_and_def shiftl_def)
 
 lemma rshift_limited_and:
   "limited_and x z \<Longrightarrow> limited_and (x >> n) (z >> n)"
-  unfolding limited_and_def
-  by (metis drop_bit_and)
+  using drop_bit_and [of n x z] by (simp add: limited_and_def shiftr_def)
 
 lemmas limited_and_simps1 = limited_and_eq_0 limited_and_eq_id
 
 lemmas is_aligned_limited_and
     = is_aligned_neg_mask_eq[unfolded mask_eq_decr_exp, folded limited_and_def]
 
 lemmas limited_and_simps = limited_and_simps1
        limited_and_simps1[OF is_aligned_limited_and]
        limited_and_simps1[OF lshift_limited_and]
        limited_and_simps1[OF rshift_limited_and]
        limited_and_simps1[OF rshift_limited_and, OF is_aligned_limited_and]
        not_one_eq
 
 definition
   from_bool :: "bool \<Rightarrow> 'a::len word" where
   "from_bool b \<equiv> case b of True \<Rightarrow> of_nat 1
                          | False \<Rightarrow> of_nat 0"
 
 lemma from_bool_eq:
   \<open>from_bool = of_bool\<close>
   by (simp add: fun_eq_iff from_bool_def)
 
 lemma from_bool_0:
   "(from_bool x = 0) = (\<not> x)"
   by (simp add: from_bool_def split: bool.split)
 
 lemma from_bool_eq_if':
   "((if P then 1 else 0) = from_bool Q) = (P = Q)"
   by (cases Q) (simp_all add: from_bool_def)
 
 definition
   to_bool :: "'a::len word \<Rightarrow> bool" where
   "to_bool \<equiv> (\<noteq>) 0"
 
 lemma to_bool_and_1:
   "to_bool (x AND 1) \<longleftrightarrow> bit x 0"
   by (simp add: to_bool_def and_one_eq mod_2_eq_odd)
 
 lemma to_bool_from_bool [simp]:
   "to_bool (from_bool r) = r"
   unfolding from_bool_def to_bool_def
   by (simp split: bool.splits)
 
 lemma from_bool_neq_0 [simp]:
   "(from_bool b \<noteq> 0) = b"
   by (simp add: from_bool_def split: bool.splits)
 
 lemma from_bool_mask_simp [simp]:
   "(from_bool r :: 'a::len word) AND 1 = from_bool r"
   unfolding from_bool_def
   by (clarsimp split: bool.splits)
 
 lemma from_bool_1 [simp]:
   "(from_bool P = 1) = P"
   by (simp add: from_bool_def split: bool.splits)
 
 lemma ge_0_from_bool [simp]:
   "(0 < from_bool P) = P"
   by (simp add: from_bool_def split: bool.splits)
 
 lemma limited_and_from_bool:
   "limited_and (from_bool b) 1"
   by (simp add: from_bool_def limited_and_def split: bool.split)
 
 lemma to_bool_1 [simp]: "to_bool 1" by (simp add: to_bool_def)
 lemma to_bool_0 [simp]: "\<not>to_bool 0" by (simp add: to_bool_def)
 
 lemma from_bool_eq_if:
   "(from_bool Q = (if P then 1 else 0)) = (P = Q)"
   by (cases Q) (simp_all add: from_bool_def)
 
 lemma to_bool_eq_0:
   "(\<not> to_bool x) = (x = 0)"
   by (simp add: to_bool_def)
 
 lemma to_bool_neq_0:
   "(to_bool x) = (x \<noteq> 0)"
   by (simp add: to_bool_def)
 
 lemma from_bool_all_helper:
   "(\<forall>bool. from_bool bool = val \<longrightarrow> P bool)
       = ((\<exists>bool. from_bool bool = val) \<longrightarrow> P (val \<noteq> 0))"
   by (auto simp: from_bool_0)
 
 lemma fold_eq_0_to_bool:
   "(v = 0) = (\<not> to_bool v)"
   by (simp add: to_bool_def)
 
 lemma from_bool_to_bool_iff:
   "w = from_bool b \<longleftrightarrow> to_bool w = b \<and> (w = 0 \<or> w = 1)"
   by (cases b) (auto simp: from_bool_def to_bool_def)
 
 lemma from_bool_eqI:
   "from_bool x = from_bool y \<Longrightarrow> x = y"
   unfolding from_bool_def
   by (auto split: bool.splits)
 
 lemma neg_mask_in_mask_range:
   "is_aligned ptr bits \<Longrightarrow> (ptr' AND NOT(mask bits) = ptr) = (ptr' \<in> mask_range ptr bits)"
   apply (erule is_aligned_get_word_bits)
    apply (rule iffI)
     apply (drule sym)
     apply (simp add: word_and_le2)
     apply (subst word_plus_and_or_coroll, word_eqI_solve)
     apply (metis bit.disj_ac(2) bit.disj_conj_distrib2 le_word_or2 word_and_max word_or_not)
    apply clarsimp
    apply (smt add.right_neutral eq_iff is_aligned_neg_mask_eq mask_out_add_aligned neg_mask_mono_le
               word_and_not)
   apply (simp add: power_overflow mask_eq_decr_exp)
   done
 
 lemma aligned_offset_in_range:
   "\<lbrakk> is_aligned (x :: 'a :: len word) m; y < 2 ^ m; is_aligned p n; n \<ge> m; n < LENGTH('a) \<rbrakk>
    \<Longrightarrow> (x + y \<in> {p .. p + mask n}) = (x \<in> mask_range p n)"
   apply (subst disjunctive_add)
    apply (simp add: bit_simps)
   apply (erule is_alignedE')
    apply (auto simp add: bit_simps not_le)[1]
    apply (metis less_2p_is_upper_bits_unset)
   apply (simp only: is_aligned_add_or word_ao_dist flip: neg_mask_in_mask_range)
   apply (subgoal_tac \<open>y AND NOT (mask n) = 0\<close>)
    apply simp
   apply (metis (full_types) is_aligned_mask is_aligned_neg_mask less_mask_eq word_bw_comms(1) word_bw_lcs(1))
   done
 
 lemma mask_range_to_bl':
   "\<lbrakk> is_aligned (ptr :: 'a :: len word) bits; bits < LENGTH('a) \<rbrakk>
    \<Longrightarrow> mask_range ptr bits
        = {x. take (LENGTH('a) - bits) (to_bl x) = take (LENGTH('a) - bits) (to_bl ptr)}"
   apply (rule set_eqI, rule iffI)
    apply clarsimp
    apply (subgoal_tac "\<exists>y. x = ptr + y \<and> y < 2 ^ bits")
     apply clarsimp
     apply (subst is_aligned_add_conv)
        apply assumption
       apply simp
     apply simp
    apply (rule_tac x="x - ptr" in exI)
    apply (simp add: add_diff_eq[symmetric])
    apply (simp only: word_less_sub_le[symmetric])
    apply (rule word_diff_ls')
     apply (simp add: field_simps mask_eq_decr_exp)
    apply assumption
   apply simp
   apply (subgoal_tac "\<exists>y. y < 2 ^ bits \<and> to_bl (ptr + y) = to_bl x")
    apply clarsimp
    apply (rule conjI)
     apply (erule(1) is_aligned_no_wrap')
    apply (simp only: add_diff_eq[symmetric] mask_eq_decr_exp)
    apply (rule word_plus_mono_right)
     apply simp
    apply (erule is_aligned_no_wrap')
    apply simp
   apply (rule_tac x="of_bl (drop (LENGTH('a) - bits) (to_bl x))" in exI)
   apply (rule context_conjI)
    apply (rule order_less_le_trans [OF of_bl_length])
     apply simp
    apply simp
   apply (subst is_aligned_add_conv)
      apply assumption
     apply simp
   apply (drule sym)
   apply (simp add: word_rep_drop)
   done
 
 lemma mask_range_to_bl:
   "is_aligned (ptr :: 'a :: len word) bits
    \<Longrightarrow> mask_range ptr bits
         = {x. take (LENGTH('a) - bits) (to_bl x) = take (LENGTH('a) - bits) (to_bl ptr)}"
   apply (erule is_aligned_get_word_bits)
    apply (erule(1) mask_range_to_bl')
   apply (rule set_eqI)
   apply (simp add: power_overflow mask_eq_decr_exp)
   done
 
 lemma aligned_mask_range_cases:
   "\<lbrakk> is_aligned (p :: 'a :: len word) n; is_aligned (p' :: 'a :: len word) n' \<rbrakk>
    \<Longrightarrow> mask_range p n \<inter> mask_range p' n' = {} \<or>
        mask_range p n \<subseteq> mask_range p' n' \<or>
        mask_range p n \<supseteq> mask_range p' n'"
   apply (simp add: mask_range_to_bl)
   apply (rule Meson.disj_comm, rule disjCI)
   apply auto
   apply (subgoal_tac "(\<exists>n''. LENGTH('a) - n = (LENGTH('a) - n') + n'')
                     \<or> (\<exists>n''. LENGTH('a) - n' = (LENGTH('a) - n) + n'')")
    apply (fastforce simp: take_add)
   apply arith
   done
 
 lemma aligned_mask_range_offset_subset:
   assumes al: "is_aligned (ptr :: 'a :: len word) sz" and al': "is_aligned x sz'"
   and szv: "sz' \<le> sz"
   and xsz: "x < 2 ^ sz"
   shows "mask_range (ptr+x) sz' \<subseteq> mask_range ptr sz"
   using al
 proof (rule is_aligned_get_word_bits)
   assume p0: "ptr = 0" and szv': "LENGTH ('a) \<le> sz"
   then have "(2 ::'a word) ^ sz = 0" by simp
   show ?thesis using p0
     by (simp add: \<open>2 ^ sz = 0\<close> mask_eq_decr_exp)
 next
   assume szv': "sz < LENGTH('a)"
 
   hence blah: "2 ^ (sz - sz') < (2 :: nat) ^ LENGTH('a)"
     using szv by auto
   show ?thesis using szv szv'
     apply auto
     using al assms(4) is_aligned_no_wrap' apply blast
     apply (simp only: flip: add_diff_eq add_mask_fold)
     apply (subst add.assoc, rule word_plus_mono_right)
      using al' is_aligned_add_less_t2n xsz
      apply fastforce
     apply (simp add: field_simps szv al is_aligned_no_overflow)
     done
 qed
 
 lemma aligned_mask_ranges_disjoint:
   "\<lbrakk> is_aligned (p :: 'a :: len word) n; is_aligned (p' :: 'a :: len word) n';
      p AND NOT(mask n') \<noteq> p'; p' AND NOT(mask n) \<noteq> p \<rbrakk>
    \<Longrightarrow> mask_range p n \<inter> mask_range p' n' = {}"
   using aligned_mask_range_cases
   by (auto simp: neg_mask_in_mask_range)
 
 lemma aligned_mask_ranges_disjoint2:
   "\<lbrakk> is_aligned p n; is_aligned ptr bits; n \<ge> m; n < size p; m \<le> bits;
      (\<forall>y < 2 ^ (n - m). p + (y << m) \<notin> mask_range ptr bits) \<rbrakk>
    \<Longrightarrow> mask_range p n \<inter> mask_range ptr bits = {}"
   apply safe
   apply (simp only: flip: neg_mask_in_mask_range)
   apply (drule_tac x="x AND mask n >> m" in spec)
   apply (erule notE[OF mp])
-   apply (rule shiftr_less_t2n)
+   apply (simp flip: take_bit_eq_mask add: shiftr_def drop_bit_take_bit)
+   apply transfer
+  apply simp
    apply (simp add: word_size and_mask_less_size)
   apply (subst disjunctive_add)
    apply (auto simp add: bit_simps word_size intro!: bit_eqI)
   done
 
 lemma word_clz_sint_upper[simp]:
   "LENGTH('a) \<ge> 3 \<Longrightarrow> sint (of_nat (word_clz (w :: 'a :: len word)) :: 'a sword) \<le> int (LENGTH('a))"
   using word_clz_max [of w]
   apply (simp add: word_size signed_of_nat)
   apply (subst signed_take_bit_int_eq_self)
     apply simp_all
    apply (metis negative_zle of_nat_numeral semiring_1_class.of_nat_power)
   apply (drule small_powers_of_2)
   apply (erule le_less_trans)
   apply simp
   done
 
 lemma word_clz_sint_lower[simp]:
   "LENGTH('a) \<ge> 3
    \<Longrightarrow> - sint (of_nat (word_clz (w :: 'a :: len word)) :: 'a signed word) \<le> int (LENGTH('a))"
   apply (subst sint_eq_uint)
   using word_clz_max [of w]
    apply (simp_all add: word_size unsigned_of_nat)
   apply (rule not_msb_from_less)
   apply (simp add: word_less_nat_alt unsigned_of_nat)
   apply (subst take_bit_nat_eq_self)
    apply (simp add: le_less_trans)
   apply (drule small_powers_of_2)
   apply (erule le_less_trans)
   apply simp
   done
 
 lemma mask_range_subsetD:
   "\<lbrakk> p' \<in> mask_range p n; x' \<in> mask_range p' n'; n' \<le> n; is_aligned p n; is_aligned p' n' \<rbrakk> \<Longrightarrow>
    x' \<in> mask_range p n"
   using aligned_mask_step by fastforce
 
-lemma nasty_split_lt:
-  "\<lbrakk> (x :: 'a:: len word) < 2 ^ (m - n); n \<le> m; m < LENGTH('a::len) \<rbrakk>
-     \<Longrightarrow> x * 2 ^ n + (2 ^ n - 1) \<le> 2 ^ m - 1"
-  apply (simp only: add_diff_eq)
-  apply (subst mult_1[symmetric], subst distrib_right[symmetric])
-  apply (rule word_sub_mono)
-     apply (rule order_trans)
-      apply (rule word_mult_le_mono1)
-        apply (rule inc_le)
-        apply assumption
-       apply (subst word_neq_0_conv[symmetric])
-       apply (rule power_not_zero)
-       apply simp
-      apply (subst unat_power_lower, simp)+
-      apply (subst power_add[symmetric])
-      apply (rule power_strict_increasing)
-       apply simp
-      apply simp
-     apply (subst power_add[symmetric])
-     apply simp
-    apply simp
-   apply (rule word_sub_1_le)
-   apply (subst mult.commute)
-   apply (subst shiftl_t2n[symmetric])
-   apply (rule word_shift_nonzero)
-     apply (erule inc_le)
-    apply simp
-   apply (unat_arith)
-  apply (drule word_power_less_1)
-  apply simp
-  done
-
-lemma nasty_split_less:
-  "\<lbrakk>m \<le> n; n \<le> nm; nm < LENGTH('a::len); x < 2 ^ (nm - n)\<rbrakk>
-   \<Longrightarrow> (x :: 'a word) * 2 ^ n + (2 ^ m - 1) < 2 ^ nm"
-  apply (simp only: word_less_sub_le[symmetric])
-  apply (rule order_trans [OF _ nasty_split_lt])
-     apply (rule word_plus_mono_right)
-      apply (rule word_sub_mono)
-         apply (simp add: word_le_nat_alt)
-        apply simp
-       apply (simp add: word_sub_1_le[OF power_not_zero])
-      apply (simp add: word_sub_1_le[OF power_not_zero])
-     apply (rule is_aligned_no_wrap')
-      apply (rule is_aligned_mult_triv2)
-     apply simp
-    apply (erule order_le_less_trans, simp)
-   apply simp+
-  done
-
 lemma add_mult_in_mask_range:
   "\<lbrakk> is_aligned (base :: 'a :: len word) n; n < LENGTH('a); bits \<le> n; x < 2 ^ (n - bits) \<rbrakk>
    \<Longrightarrow> base + x * 2^bits \<in> mask_range base n"
   by (simp add: is_aligned_no_wrap' mask_2pm1 nasty_split_lt word_less_power_trans2
                 word_plus_mono_right)
 
 lemma from_to_bool_last_bit:
   "from_bool (to_bool (x AND 1)) = x AND 1"
   by (metis from_bool_to_bool_iff word_and_1)
 
 lemma sint_ctz:
   \<open>0 \<le> sint (of_nat (word_ctz (x :: 'a :: len word)) :: 'a signed word)
      \<and> sint (of_nat (word_ctz x) :: 'a signed word) \<le> int (LENGTH('a))\<close> (is \<open>?P \<and> ?Q\<close>)
   if \<open>LENGTH('a) > 2\<close>
 proof
   have *: \<open>word_ctz x < 2 ^ (LENGTH('a) - Suc 0)\<close>
     using word_ctz_le apply (rule le_less_trans)
     using that small_powers_of_2 [of \<open>LENGTH('a)\<close>] apply simp
     done
   have \<open>int (word_ctz x) div 2 ^ (LENGTH('a) - Suc 0) = 0\<close>
     apply (rule div_pos_pos_trivial)
      apply (simp_all add: *)
     done
   then show ?P by (simp add: signed_of_nat bit_iff_odd)
   show ?Q
     apply (auto simp add: signed_of_nat)
     apply (subst signed_take_bit_int_eq_self)
       apply (auto simp add: word_ctz_le * minus_le_iff [of _ \<open>int (word_ctz x)\<close>])
     apply (rule order.trans [of _ 0])
      apply simp_all
     done
 qed
 
 lemma unat_of_nat_word_log2:
   "LENGTH('a) < 2 ^ LENGTH('b)
    \<Longrightarrow> unat (of_nat (word_log2 (n :: 'a :: len word)) :: 'b :: len word) = word_log2 n"
   by (metis less_trans unat_of_nat_eq word_log2_max word_size)
 
 lemma aligned_mask_diff:
   "\<lbrakk> is_aligned (dest :: 'a :: len word) bits; is_aligned (ptr :: 'a :: len word) sz;
      bits \<le> sz; sz < LENGTH('a); dest < ptr \<rbrakk>
    \<Longrightarrow> mask bits + dest < ptr"
   apply (frule_tac p' = ptr in aligned_mask_range_cases, assumption)
   apply (elim disjE)
     apply (drule_tac is_aligned_no_overflow_mask, simp)+
     apply (simp add: algebra_split_simps word_le_not_less)
    apply (drule is_aligned_no_overflow_mask; fastforce)
   apply (simp add: is_aligned_weaken algebra_split_simps)
   apply (auto simp add: not_le)
   using is_aligned_no_overflow_mask leD apply blast
   apply (meson aligned_add_mask_less_eq is_aligned_weaken le_less_trans)
   done
 
 end
 
 end
\ No newline at end of file
diff --git a/thys/Word_Lib/Most_significant_bit.thy b/thys/Word_Lib/Most_significant_bit.thy
--- a/thys/Word_Lib/Most_significant_bit.thy
+++ b/thys/Word_Lib/Most_significant_bit.thy
@@ -1,193 +1,194 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (* Author: Jeremy Dawson, NICTA *)
 
 section \<open>Dedicated operation for the most significant bit\<close>
 
 theory Most_significant_bit
   imports
     "HOL-Library.Word"
+    Bit_Shifts_Infix_Syntax
     More_Word
     More_Arithmetic
 begin
 
 class msb =
   fixes msb :: \<open>'a \<Rightarrow> bool\<close>
 
 instantiation int :: msb
 begin
 
 definition \<open>msb x \<longleftrightarrow> x < 0\<close> for x :: int
 
 instance ..
 
 end
 
 lemma msb_bin_rest [simp]: "msb (x div 2) = msb x"
   for x :: int
   by (simp add: msb_int_def)
 
 context
   includes bit_operations_syntax
 begin
 
 lemma int_msb_and [simp]: "msb ((x :: int) AND y) \<longleftrightarrow> msb x \<and> msb y"
 by(simp add: msb_int_def)
 
 lemma int_msb_or [simp]: "msb ((x :: int) OR y) \<longleftrightarrow> msb x \<or> msb y"
 by(simp add: msb_int_def)
 
 lemma int_msb_xor [simp]: "msb ((x :: int) XOR y) \<longleftrightarrow> msb x \<noteq> msb y"
 by(simp add: msb_int_def)
 
 lemma int_msb_not [simp]: "msb (NOT (x :: int)) \<longleftrightarrow> \<not> msb x"
 by(simp add: msb_int_def not_less)
 
 end
 
-lemma msb_shiftl [simp]: "msb (push_bit n (x :: int)) \<longleftrightarrow> msb x"
-by(simp add: msb_int_def)
+lemma msb_shiftl [simp]: "msb ((x :: int) << n) \<longleftrightarrow> msb x"
+  by (simp add: msb_int_def shiftl_def)
 
-lemma msb_shiftr [simp]: "msb (drop_bit r (x :: int)) \<longleftrightarrow> msb x"
-by(simp add: msb_int_def)
+lemma msb_shiftr [simp]: "msb ((x :: int) >> r) \<longleftrightarrow> msb x"
+  by (simp add: msb_int_def shiftr_def)
 
 lemma msb_0 [simp]: "msb (0 :: int) = False"
 by(simp add: msb_int_def)
 
 lemma msb_1 [simp]: "msb (1 :: int) = False"
 by(simp add: msb_int_def)
 
 lemma msb_numeral [simp]:
   "msb (numeral n :: int) = False"
   "msb (- numeral n :: int) = True"
 by(simp_all add: msb_int_def)
 
 instantiation word :: (len) msb
 begin
 
 definition msb_word :: \<open>'a word \<Rightarrow> bool\<close>
   where msb_word_iff_bit: \<open>msb w \<longleftrightarrow> bit w (LENGTH('a) - Suc 0)\<close> for w :: \<open>'a::len word\<close>
 
 instance ..
 
 end
 
 lemma msb_word_eq:
   \<open>msb w \<longleftrightarrow> bit w (LENGTH('a) - 1)\<close> for w :: \<open>'a::len word\<close>
   by (simp add: msb_word_iff_bit)
 
 lemma word_msb_sint: "msb w \<longleftrightarrow> sint w < 0"
   by (simp add: msb_word_eq bit_last_iff)
 
 lemma msb_word_iff_sless_0:
   \<open>msb w \<longleftrightarrow> w <s 0\<close>
   by (simp add: word_msb_sint word_sless_alt)
 
 lemma msb_word_of_int:
   "msb (word_of_int x::'a::len word) = bit x (LENGTH('a) - 1)"
   by (simp add: msb_word_iff_bit bit_simps)
 
 lemma word_msb_numeral [simp]:
   "msb (numeral w::'a::len word) = bit (numeral w :: int) (LENGTH('a) - 1)"
   unfolding word_numeral_alt by (rule msb_word_of_int)
 
 lemma word_msb_neg_numeral [simp]:
   "msb (- numeral w::'a::len word) = bit (- numeral w :: int) (LENGTH('a) - 1)"
   unfolding word_neg_numeral_alt by (rule msb_word_of_int)
 
 lemma word_msb_0 [simp]: "\<not> msb (0::'a::len word)"
   by (simp add: msb_word_iff_bit)
 
 lemma word_msb_1 [simp]: "msb (1::'a::len word) \<longleftrightarrow> LENGTH('a) = 1"
   by (simp add: msb_word_iff_bit le_Suc_eq)
 
 lemma word_msb_nth: "msb w = bit (uint w) (LENGTH('a) - 1)"
   for w :: "'a::len word"
   by (simp add: msb_word_iff_bit bit_simps)
 
 lemma msb_nth: "msb w = bit w (LENGTH('a) - 1)"
   for w :: "'a::len word"
   by (fact msb_word_eq)
   
 lemma word_msb_n1 [simp]: "msb (-1::'a::len word)"
   by (simp add: msb_word_eq not_le)
 
-lemma msb_shift: "msb w \<longleftrightarrow> drop_bit (LENGTH('a) - 1) w \<noteq> 0"
+lemma msb_shift: "msb w \<longleftrightarrow> w >> LENGTH('a) - 1 \<noteq> 0"
   for w :: "'a::len word"
-  by (simp add: msb_word_eq bit_iff_odd_drop_bit drop_bit_eq_zero_iff_not_bit_last)
+  by (simp add: drop_bit_eq_zero_iff_not_bit_last msb_word_eq shiftr_def)
 
 lemmas word_ops_msb = msb1 [unfolded msb_nth [symmetric, unfolded One_nat_def]]
 
 lemma word_sint_msb_eq: "sint x = uint x - (if msb x then 2 ^ size x else 0)"
   apply (cases \<open>LENGTH('a)\<close>)
   apply (simp_all add: msb_word_iff_bit word_size)
   apply transfer
   apply (simp add: signed_take_bit_eq_take_bit_minus)
   done
 
 lemma word_sle_msb_le: "x <=s y \<longleftrightarrow> (msb y \<longrightarrow> msb x) \<and> ((msb x \<and> \<not> msb y) \<or> x \<le> y)"
   apply (simp add: word_sle_eq word_sint_msb_eq word_size word_le_def)
   apply safe
    apply (rule order_trans[OF _ uint_ge_0])
    apply (simp add: order_less_imp_le)
   apply (erule notE[OF leD])
   apply (rule order_less_le_trans[OF _ uint_ge_0])
   apply simp
   done
 
 lemma word_sless_msb_less: "x <s y \<longleftrightarrow> (msb y \<longrightarrow> msb x) \<and> ((msb x \<and> \<not> msb y) \<or> x < y)"
   by (auto simp add: word_sless_eq word_sle_msb_le)
 
 lemma not_msb_from_less:
   "(v :: 'a word) < 2 ^ (LENGTH('a :: len) - 1) \<Longrightarrow> \<not> msb v"
   apply (clarsimp simp add: msb_nth)
   apply (drule less_mask_eq)
   apply (drule word_eqD, drule(1) iffD2)
   apply (simp add: bit_simps)
   done
 
 lemma sint_eq_uint:
   "\<not> msb x \<Longrightarrow> sint x = uint x"
   apply (cases \<open>LENGTH('a)\<close>)
   apply (simp_all add: msb_word_iff_bit)
   apply transfer
   apply (simp add: signed_take_bit_eq_take_bit_minus)
   done
 
 lemma scast_eq_ucast:
   "\<not> msb x \<Longrightarrow> scast x = ucast x"
   apply (cases \<open>LENGTH('a)\<close>)
   apply simp
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_signed_iff bit_unsigned_iff min_def msb_word_eq)
   apply (erule notE)
   apply (metis le_less_Suc_eq test_bit_bin)
   done
 
 lemma msb_ucast_eq:
     "LENGTH('a) = LENGTH('b) \<Longrightarrow>
          msb (ucast x :: ('a::len) word) = msb (x :: ('b::len) word)"
   by (simp add: msb_word_eq bit_simps)
 
 lemma msb_big:
   \<open>msb a \<longleftrightarrow> 2 ^ (LENGTH('a) - Suc 0) \<le> a\<close>
   for a :: \<open>'a::len word\<close>
   using bang_is_le [of a \<open>LENGTH('a) - Suc 0\<close>]
   apply (auto simp add: msb_nth word_le_not_less)
   apply (rule ccontr)
   apply (erule notE)
   apply (rule ccontr)
   apply (clarsimp simp: not_less)
   apply (subgoal_tac "a = take_bit (LENGTH('a) - Suc 0) a")
    apply (cut_tac and_mask_less' [where w=a and n="LENGTH('a) - Suc 0"])
     apply auto
   apply (simp flip: take_bit_eq_mask)
   apply (rule sym)
   apply (simp add: take_bit_eq_self_iff_drop_bit_eq_0 drop_bit_eq_zero_iff_not_bit_last)
   done
 
 end
diff --git a/thys/Word_Lib/Next_and_Prev.thy b/thys/Word_Lib/Next_and_Prev.thy
--- a/thys/Word_Lib/Next_and_Prev.thy
+++ b/thys/Word_Lib/Next_and_Prev.thy
@@ -1,51 +1,51 @@
 (*
  * Copyright Julius Michaelis, Cornelius Diekmann
  * SPDX-License-Identifier: BSD-3-Clause
  *)
 
 section\<open>Increment and Decrement Machine Words Without Wrap-Around\<close>
 
 theory Next_and_Prev
 imports
   Aligned
 begin
 
 text \<open>Previous and next words addresses, without wrap around.\<close>
 
 lift_definition word_next :: \<open>'a::len word \<Rightarrow> 'a word\<close>
   is \<open>\<lambda>k. if 2 ^ LENGTH('a) dvd k + 1 then - 1 else k + 1\<close>
   by (simp flip: take_bit_eq_0_iff) (metis take_bit_add)
 
 lift_definition word_prev :: \<open>'a::len word \<Rightarrow> 'a word\<close>
   is \<open>\<lambda>k. if 2 ^ LENGTH('a) dvd k then 0 else k - 1\<close>
   by (simp flip: take_bit_eq_0_iff) (metis take_bit_diff)
 
 lemma word_next_unfold:
   \<open>word_next w = (if w = - 1 then - 1 else w + 1)\<close>
-  by transfer (simp add: take_bit_minus_one_eq_mask flip: take_bit_eq_mask_iff_exp_dvd)
+  by transfer (simp flip: take_bit_eq_mask_iff_exp_dvd)
 
 lemma word_prev_unfold:
   \<open>word_prev w = (if w = 0 then 0 else w - 1)\<close>
   by transfer (simp flip: take_bit_eq_0_iff)
 
 lemma [code]:
   \<open>Word.the_int (word_next w :: 'a::len word) =
     (if w = - 1 then Word.the_int w else Word.the_int w + 1)\<close>
   by transfer
-    (simp add: take_bit_minus_one_eq_mask mask_eq_exp_minus_1 take_bit_incr_eq flip: take_bit_eq_mask_iff_exp_dvd)
+    (simp add: mask_eq_exp_minus_1 take_bit_incr_eq flip: take_bit_eq_mask_iff_exp_dvd)
 
 lemma [code]:
   \<open>Word.the_int (word_prev w :: 'a::len word) =
     (if w = 0 then Word.the_int w else Word.the_int w - 1)\<close>
   by transfer (simp add: take_bit_eq_0_iff take_bit_decr_eq)
 
 lemma word_adjacent_union:
   "word_next e = s' \<Longrightarrow> s \<le> e \<Longrightarrow> s' \<le> e' \<Longrightarrow> {s..e} \<union> {s'..e'} = {s .. e'}"
   apply (simp add: word_next_unfold ivl_disj_un_two_touch split: if_splits)
   apply (drule sym)
   apply simp
   apply (subst word_atLeastLessThan_Suc_atLeastAtMost_union)
      apply (simp_all add: word_Suc_le)
   done
 
 end
diff --git a/thys/Word_Lib/Reversed_Bit_Lists.thy b/thys/Word_Lib/Reversed_Bit_Lists.thy
--- a/thys/Word_Lib/Reversed_Bit_Lists.thy
+++ b/thys/Word_Lib/Reversed_Bit_Lists.thy
@@ -1,2250 +1,2240 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (* Author: Jeremy Dawson, NICTA *)
 
 section \<open>Bit values as reversed lists of bools\<close>
 
 theory Reversed_Bit_Lists
   imports
     "HOL-Library.Word"
     Typedef_Morphisms
     Least_significant_bit
     Most_significant_bit
     Even_More_List
     "HOL-Library.Sublist"
     Aligned
     Singleton_Bit_Shifts
     Legacy_Aliases
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 lemma horner_sum_of_bool_2_concat:
   \<open>horner_sum of_bool 2 (concat (map (\<lambda>x. map (bit x) [0..<LENGTH('a)]) ws)) = horner_sum uint (2 ^ LENGTH('a)) ws\<close>
   for ws :: \<open>'a::len word list\<close>
 proof (induction ws)
   case Nil
   then show ?case
     by simp
 next
   case (Cons w ws)
   moreover have \<open>horner_sum of_bool 2 (map (bit w) [0..<LENGTH('a)]) = uint w\<close>
   proof transfer
     fix k :: int
     have \<open>map (\<lambda>n. n < LENGTH('a) \<and> bit k n) [0..<LENGTH('a)]
       = map (bit k) [0..<LENGTH('a)]\<close>
       by simp
     then show \<open>horner_sum of_bool 2 (map (\<lambda>n. n < LENGTH('a) \<and> bit k n) [0..<LENGTH('a)])
       = take_bit LENGTH('a) k\<close>
       by (simp only: horner_sum_bit_eq_take_bit)
   qed
   ultimately show ?case
     by (simp add: horner_sum_append)
 qed
 
 
 subsection \<open>Implicit augmentation of list prefixes\<close>
 
 primrec takefill :: "'a \<Rightarrow> nat \<Rightarrow> 'a list \<Rightarrow> 'a list"
 where
     Z: "takefill fill 0 xs = []"
   | Suc: "takefill fill (Suc n) xs =
       (case xs of
         [] \<Rightarrow> fill # takefill fill n xs
       | y # ys \<Rightarrow> y # takefill fill n ys)"
 
 lemma nth_takefill: "m < n \<Longrightarrow> takefill fill n l ! m = (if m < length l then l ! m else fill)"
   apply (induct n arbitrary: m l)
    apply clarsimp
   apply clarsimp
   apply (case_tac m)
    apply (simp split: list.split)
   apply (simp split: list.split)
   done
 
 lemma takefill_alt: "takefill fill n l = take n l @ replicate (n - length l) fill"
   by (induct n arbitrary: l) (auto split: list.split)
 
 lemma takefill_replicate [simp]: "takefill fill n (replicate m fill) = replicate n fill"
   by (simp add: takefill_alt replicate_add [symmetric])
 
 lemma takefill_le': "n = m + k \<Longrightarrow> takefill x m (takefill x n l) = takefill x m l"
   by (induct m arbitrary: l n) (auto split: list.split)
 
 lemma length_takefill [simp]: "length (takefill fill n l) = n"
   by (simp add: takefill_alt)
 
 lemma take_takefill': "n = k + m \<Longrightarrow> take k (takefill fill n w) = takefill fill k w"
   by (induct k arbitrary: w n) (auto split: list.split)
 
 lemma drop_takefill: "drop k (takefill fill (m + k) w) = takefill fill m (drop k w)"
   by (induct k arbitrary: w) (auto split: list.split)
 
 lemma takefill_le [simp]: "m \<le> n \<Longrightarrow> takefill x m (takefill x n l) = takefill x m l"
   by (auto simp: le_iff_add takefill_le')
 
 lemma take_takefill [simp]: "m \<le> n \<Longrightarrow> take m (takefill fill n w) = takefill fill m w"
   by (auto simp: le_iff_add take_takefill')
 
 lemma takefill_append: "takefill fill (m + length xs) (xs @ w) = xs @ (takefill fill m w)"
   by (induct xs) auto
 
 lemma takefill_same': "l = length xs \<Longrightarrow> takefill fill l xs = xs"
   by (induct xs arbitrary: l) auto
 
 lemmas takefill_same [simp] = takefill_same' [OF refl]
 
 lemma tf_rev:
   "n + k = m + length bl \<Longrightarrow> takefill x m (rev (takefill y n bl)) =
     rev (takefill y m (rev (takefill x k (rev bl))))"
   apply (rule nth_equalityI)
    apply (auto simp add: nth_takefill rev_nth)
   apply (rule_tac f = "\<lambda>n. bl ! n" in arg_cong)
   apply arith
   done
 
 lemma takefill_minus: "0 < n \<Longrightarrow> takefill fill (Suc (n - 1)) w = takefill fill n w"
   by auto
 
 lemmas takefill_Suc_cases =
   list.cases [THEN takefill.Suc [THEN trans]]
 
 lemmas takefill_Suc_Nil = takefill_Suc_cases (1)
 lemmas takefill_Suc_Cons = takefill_Suc_cases (2)
 
 lemmas takefill_minus_simps = takefill_Suc_cases [THEN [2]
   takefill_minus [symmetric, THEN trans]]
 
 lemma takefill_numeral_Nil [simp]:
   "takefill fill (numeral k) [] = fill # takefill fill (pred_numeral k) []"
   by (simp add: numeral_eq_Suc)
 
 lemma takefill_numeral_Cons [simp]:
   "takefill fill (numeral k) (x # xs) = x # takefill fill (pred_numeral k) xs"
   by (simp add: numeral_eq_Suc)
 
 
 subsection \<open>Range projection\<close>
 
 definition bl_of_nth :: "nat \<Rightarrow> (nat \<Rightarrow> 'a) \<Rightarrow> 'a list"
   where "bl_of_nth n f = map f (rev [0..<n])"
 
 lemma bl_of_nth_simps [simp, code]:
   "bl_of_nth 0 f = []"
   "bl_of_nth (Suc n) f = f n # bl_of_nth n f"
   by (simp_all add: bl_of_nth_def)
 
 lemma length_bl_of_nth [simp]: "length (bl_of_nth n f) = n"
   by (simp add: bl_of_nth_def)
 
 lemma nth_bl_of_nth [simp]: "m < n \<Longrightarrow> rev (bl_of_nth n f) ! m = f m"
   by (simp add: bl_of_nth_def rev_map)
 
 lemma bl_of_nth_inj: "(\<And>k. k < n \<Longrightarrow> f k = g k) \<Longrightarrow> bl_of_nth n f = bl_of_nth n g"
   by (simp add: bl_of_nth_def)
 
 lemma bl_of_nth_nth_le: "n \<le> length xs \<Longrightarrow> bl_of_nth n (nth (rev xs)) = drop (length xs - n) xs"
   apply (induct n arbitrary: xs)
    apply clarsimp
   apply clarsimp
   apply (rule trans [OF _ hd_Cons_tl])
    apply (frule Suc_le_lessD)
    apply (simp add: rev_nth trans [OF drop_Suc drop_tl, symmetric])
    apply (subst hd_drop_conv_nth)
     apply force
    apply simp_all
   apply (rule_tac f = "\<lambda>n. drop n xs" in arg_cong)
   apply simp
   done
 
 lemma bl_of_nth_nth [simp]: "bl_of_nth (length xs) ((!) (rev xs)) = xs"
   by (simp add: bl_of_nth_nth_le)
 
 
 subsection \<open>More\<close>
 
 definition rotater1 :: "'a list \<Rightarrow> 'a list"
   where "rotater1 ys =
     (case ys of [] \<Rightarrow> [] | x # xs \<Rightarrow> last ys # butlast ys)"
 
 definition rotater :: "nat \<Rightarrow> 'a list \<Rightarrow> 'a list"
   where "rotater n = rotater1 ^^ n"
 
 lemmas rotater_0' [simp] = rotater_def [where n = "0", simplified]
 
 lemma rotate1_rl': "rotater1 (l @ [a]) = a # l"
   by (cases l) (auto simp: rotater1_def)
 
 lemma rotate1_rl [simp] : "rotater1 (rotate1 l) = l"
   apply (unfold rotater1_def)
   apply (cases "l")
    apply (case_tac [2] "list")
     apply auto
   done
 
 lemma rotate1_lr [simp] : "rotate1 (rotater1 l) = l"
   by (cases l) (auto simp: rotater1_def)
 
 lemma rotater1_rev': "rotater1 (rev xs) = rev (rotate1 xs)"
   by (cases "xs") (simp add: rotater1_def, simp add: rotate1_rl')
 
 lemma rotater_rev': "rotater n (rev xs) = rev (rotate n xs)"
   by (induct n) (auto simp: rotater_def intro: rotater1_rev')
 
 lemma rotater_rev: "rotater n ys = rev (rotate n (rev ys))"
   using rotater_rev' [where xs = "rev ys"] by simp
 
 lemma rotater_drop_take:
   "rotater n xs =
     drop (length xs - n mod length xs) xs @
     take (length xs - n mod length xs) xs"
   by (auto simp: rotater_rev rotate_drop_take rev_take rev_drop)
 
 lemma rotater_Suc [simp]: "rotater (Suc n) xs = rotater1 (rotater n xs)"
   unfolding rotater_def by auto
 
 lemma nth_rotater:
   \<open>rotater m xs ! n = xs ! ((n + (length xs - m mod length xs)) mod length xs)\<close> if \<open>n < length xs\<close>
   using that by (simp add: rotater_drop_take nth_append not_less less_diff_conv ac_simps le_mod_geq)
 
 lemma nth_rotater1:
   \<open>rotater1 xs ! n = xs ! ((n + (length xs - 1)) mod length xs)\<close> if \<open>n < length xs\<close>
   using that nth_rotater [of n xs 1] by simp
 
 lemma rotate_inv_plus [rule_format]:
   "\<forall>k. k = m + n \<longrightarrow> rotater k (rotate n xs) = rotater m xs \<and>
     rotate k (rotater n xs) = rotate m xs \<and>
     rotater n (rotate k xs) = rotate m xs \<and>
     rotate n (rotater k xs) = rotater m xs"
   by (induct n) (auto simp: rotater_def rotate_def intro: funpow_swap1 [THEN trans])
 
 lemmas rotate_inv_rel = le_add_diff_inverse2 [symmetric, THEN rotate_inv_plus]
 
 lemmas rotate_inv_eq = order_refl [THEN rotate_inv_rel, simplified]
 
 lemmas rotate_lr [simp] = rotate_inv_eq [THEN conjunct1]
 lemmas rotate_rl [simp] = rotate_inv_eq [THEN conjunct2, THEN conjunct1]
 
 lemma rotate_gal: "rotater n xs = ys \<longleftrightarrow> rotate n ys = xs"
   by auto
 
 lemma rotate_gal': "ys = rotater n xs \<longleftrightarrow> xs = rotate n ys"
   by auto
 
 lemma length_rotater [simp]: "length (rotater n xs) = length xs"
   by (simp add : rotater_rev)
 
 lemma rotate_eq_mod: "m mod length xs = n mod length xs \<Longrightarrow> rotate m xs = rotate n xs"
   apply (rule box_equals)
     defer
     apply (rule rotate_conv_mod [symmetric])+
   apply simp
   done
 
 lemma restrict_to_left: "x = y \<Longrightarrow> x = z \<longleftrightarrow> y = z"
   by simp
 
 lemmas rotate_eqs =
   trans [OF rotate0 [THEN fun_cong] id_apply]
   rotate_rotate [symmetric]
   rotate_id
   rotate_conv_mod
   rotate_eq_mod
 
 lemmas rrs0 = rotate_eqs [THEN restrict_to_left,
   simplified rotate_gal [symmetric] rotate_gal' [symmetric]]
 lemmas rrs1 = rrs0 [THEN refl [THEN rev_iffD1]]
 lemmas rotater_eqs = rrs1 [simplified length_rotater]
 lemmas rotater_0 = rotater_eqs (1)
 lemmas rotater_add = rotater_eqs (2)
 
 lemma butlast_map: "xs \<noteq> [] \<Longrightarrow> butlast (map f xs) = map f (butlast xs)"
   by (induct xs) auto
 
 lemma rotater1_map: "rotater1 (map f xs) = map f (rotater1 xs)"
   by (cases xs) (auto simp: rotater1_def last_map butlast_map)
 
 lemma rotater_map: "rotater n (map f xs) = map f (rotater n xs)"
   by (induct n) (auto simp: rotater_def rotater1_map)
 
 lemma but_last_zip [rule_format] :
   "\<forall>ys. length xs = length ys \<longrightarrow> xs \<noteq> [] \<longrightarrow>
     last (zip xs ys) = (last xs, last ys) \<and>
     butlast (zip xs ys) = zip (butlast xs) (butlast ys)"
   apply (induct xs)
    apply auto
      apply ((case_tac ys, auto simp: neq_Nil_conv)[1])+
   done
 
 lemma but_last_map2 [rule_format] :
   "\<forall>ys. length xs = length ys \<longrightarrow> xs \<noteq> [] \<longrightarrow>
     last (map2 f xs ys) = f (last xs) (last ys) \<and>
     butlast (map2 f xs ys) = map2 f (butlast xs) (butlast ys)"
   apply (induct xs)
    apply auto
      apply ((case_tac ys, auto simp: neq_Nil_conv)[1])+
   done
 
 lemma rotater1_zip:
   "length xs = length ys \<Longrightarrow>
     rotater1 (zip xs ys) = zip (rotater1 xs) (rotater1 ys)"
   apply (unfold rotater1_def)
   apply (cases xs)
    apply auto
    apply ((case_tac ys, auto simp: neq_Nil_conv but_last_zip)[1])+
   done
 
 lemma rotater1_map2:
   "length xs = length ys \<Longrightarrow>
     rotater1 (map2 f xs ys) = map2 f (rotater1 xs) (rotater1 ys)"
   by (simp add: rotater1_map rotater1_zip)
 
 lemmas lrth =
   box_equals [OF asm_rl length_rotater [symmetric]
                  length_rotater [symmetric],
               THEN rotater1_map2]
 
 lemma rotater_map2:
   "length xs = length ys \<Longrightarrow>
     rotater n (map2 f xs ys) = map2 f (rotater n xs) (rotater n ys)"
   by (induct n) (auto intro!: lrth)
 
 lemma rotate1_map2:
   "length xs = length ys \<Longrightarrow>
     rotate1 (map2 f xs ys) = map2 f (rotate1 xs) (rotate1 ys)"
   by (cases xs; cases ys) auto
 
 lemmas lth = box_equals [OF asm_rl length_rotate [symmetric]
   length_rotate [symmetric], THEN rotate1_map2]
 
 lemma rotate_map2:
   "length xs = length ys \<Longrightarrow>
     rotate n (map2 f xs ys) = map2 f (rotate n xs) (rotate n ys)"
   by (induct n) (auto intro!: lth)
 
 
 subsection \<open>Explicit bit representation of \<^typ>\<open>int\<close>\<close>
 
 primrec bl_to_bin_aux :: "bool list \<Rightarrow> int \<Rightarrow> int"
   where
     Nil: "bl_to_bin_aux [] w = w"
   | Cons: "bl_to_bin_aux (b # bs) w = bl_to_bin_aux bs (of_bool b + 2 * w)"
 
 definition bl_to_bin :: "bool list \<Rightarrow> int"
   where "bl_to_bin bs = bl_to_bin_aux bs 0"
 
 primrec bin_to_bl_aux :: "nat \<Rightarrow> int \<Rightarrow> bool list \<Rightarrow> bool list"
   where
     Z: "bin_to_bl_aux 0 w bl = bl"
   | Suc: "bin_to_bl_aux (Suc n) w bl = bin_to_bl_aux n (w div 2) (odd w # bl)"
 
 definition bin_to_bl :: "nat \<Rightarrow> int \<Rightarrow> bool list"
   where "bin_to_bl n w = bin_to_bl_aux n w []"
 
 lemma bin_to_bl_aux_zero_minus_simp [simp]:
   "0 < n \<Longrightarrow> bin_to_bl_aux n 0 bl = bin_to_bl_aux (n - 1) 0 (False # bl)"
   by (cases n) auto
 
 lemma bin_to_bl_aux_minus1_minus_simp [simp]:
   "0 < n \<Longrightarrow> bin_to_bl_aux n (- 1) bl = bin_to_bl_aux (n - 1) (- 1) (True # bl)"
   by (cases n) auto
 
 lemma bin_to_bl_aux_one_minus_simp [simp]:
   "0 < n \<Longrightarrow> bin_to_bl_aux n 1 bl = bin_to_bl_aux (n - 1) 0 (True # bl)"
   by (cases n) auto
 
 lemma bin_to_bl_aux_Bit0_minus_simp [simp]:
   "0 < n \<Longrightarrow>
     bin_to_bl_aux n (numeral (Num.Bit0 w)) bl = bin_to_bl_aux (n - 1) (numeral w) (False # bl)"
   by (cases n) simp_all
 
 lemma bin_to_bl_aux_Bit1_minus_simp [simp]:
   "0 < n \<Longrightarrow>
     bin_to_bl_aux n (numeral (Num.Bit1 w)) bl = bin_to_bl_aux (n - 1) (numeral w) (True # bl)"
   by (cases n) simp_all
 
 lemma bl_to_bin_aux_append: "bl_to_bin_aux (bs @ cs) w = bl_to_bin_aux cs (bl_to_bin_aux bs w)"
   by (induct bs arbitrary: w) auto
 
 lemma bin_to_bl_aux_append: "bin_to_bl_aux n w bs @ cs = bin_to_bl_aux n w (bs @ cs)"
   by (induct n arbitrary: w bs) auto
 
 lemma bl_to_bin_append: "bl_to_bin (bs @ cs) = bl_to_bin_aux cs (bl_to_bin bs)"
   unfolding bl_to_bin_def by (rule bl_to_bin_aux_append)
 
 lemma bin_to_bl_aux_alt: "bin_to_bl_aux n w bs = bin_to_bl n w @ bs"
   by (simp add: bin_to_bl_def bin_to_bl_aux_append)
 
 lemma bin_to_bl_0 [simp]: "bin_to_bl 0 bs = []"
   by (auto simp: bin_to_bl_def)
 
 lemma size_bin_to_bl_aux: "length (bin_to_bl_aux n w bs) = n + length bs"
   by (induct n arbitrary: w bs) auto
 
 lemma size_bin_to_bl [simp]: "length (bin_to_bl n w) = n"
   by (simp add: bin_to_bl_def size_bin_to_bl_aux)
 
 lemma bl_bin_bl': "bin_to_bl (n + length bs) (bl_to_bin_aux bs w) = bin_to_bl_aux n w bs"
   apply (induct bs arbitrary: w n)
    apply auto
     apply (simp_all only: add_Suc [symmetric])
     apply (auto simp add: bin_to_bl_def)
   done
 
 lemma bl_bin_bl [simp]: "bin_to_bl (length bs) (bl_to_bin bs) = bs"
   unfolding bl_to_bin_def
   apply (rule box_equals)
     apply (rule bl_bin_bl')
    prefer 2
    apply (rule bin_to_bl_aux.Z)
   apply simp
   done
 
 lemma bl_to_bin_inj: "bl_to_bin bs = bl_to_bin cs \<Longrightarrow> length bs = length cs \<Longrightarrow> bs = cs"
   apply (rule_tac box_equals)
     defer
     apply (rule bl_bin_bl)
    apply (rule bl_bin_bl)
   apply simp
   done
 
 lemma bl_to_bin_False [simp]: "bl_to_bin (False # bl) = bl_to_bin bl"
   by (auto simp: bl_to_bin_def)
 
 lemma bl_to_bin_Nil [simp]: "bl_to_bin [] = 0"
   by (auto simp: bl_to_bin_def)
 
 lemma bin_to_bl_zero_aux: "bin_to_bl_aux n 0 bl = replicate n False @ bl"
   by (induct n arbitrary: bl) (auto simp: replicate_app_Cons_same)
 
 lemma bin_to_bl_zero: "bin_to_bl n 0 = replicate n False"
   by (simp add: bin_to_bl_def bin_to_bl_zero_aux)
 
 lemma bin_to_bl_minus1_aux: "bin_to_bl_aux n (- 1) bl = replicate n True @ bl"
   by (induct n arbitrary: bl) (auto simp: replicate_app_Cons_same)
 
 lemma bin_to_bl_minus1: "bin_to_bl n (- 1) = replicate n True"
   by (simp add: bin_to_bl_def bin_to_bl_minus1_aux)
 
 
 subsection \<open>Semantic interpretation of \<^typ>\<open>bool list\<close> as \<^typ>\<open>int\<close>\<close>
 
 lemma bin_bl_bin': "bl_to_bin (bin_to_bl_aux n w bs) = bl_to_bin_aux bs (take_bit n w)"
   by (induct n arbitrary: w bs) (auto simp: bl_to_bin_def take_bit_Suc ac_simps mod_2_eq_odd)
 
 lemma bin_bl_bin [simp]: "bl_to_bin (bin_to_bl n w) = take_bit n w"
   by (auto simp: bin_to_bl_def bin_bl_bin')
 
 lemma bl_to_bin_rep_F: "bl_to_bin (replicate n False @ bl) = bl_to_bin bl"
   by (simp add: bin_to_bl_zero_aux [symmetric] bin_bl_bin') (simp add: bl_to_bin_def)
 
 lemma bin_to_bl_trunc [simp]: "n \<le> m \<Longrightarrow> bin_to_bl n (take_bit m w) = bin_to_bl n w"
   by (auto intro: bl_to_bin_inj)
 
 lemma bin_to_bl_aux_bintr:
   "bin_to_bl_aux n (take_bit m bin) bl =
     replicate (n - m) False @ bin_to_bl_aux (min n m) bin bl"
   apply (induct n arbitrary: m bin bl)
    apply clarsimp
   apply clarsimp
   apply (case_tac "m")
    apply (clarsimp simp: bin_to_bl_zero_aux)
    apply (erule thin_rl)
    apply (induct_tac n)
     apply (auto simp add: take_bit_Suc)
   done
 
 lemma bin_to_bl_bintr:
   "bin_to_bl n (take_bit m bin) = replicate (n - m) False @ bin_to_bl (min n m) bin"
   unfolding bin_to_bl_def by (rule bin_to_bl_aux_bintr)
 
 lemma bl_to_bin_rep_False: "bl_to_bin (replicate n False) = 0"
   by (induct n) auto
 
 lemma len_bin_to_bl_aux: "length (bin_to_bl_aux n w bs) = n + length bs"
   by (fact size_bin_to_bl_aux)
 
 lemma len_bin_to_bl: "length (bin_to_bl n w) = n"
   by (fact size_bin_to_bl) (* FIXME: duplicate *)
 
 lemma sign_bl_bin': "bin_sign (bl_to_bin_aux bs w) = bin_sign w"
   by (induction bs arbitrary: w) (simp_all add: bin_sign_def)
 
 lemma sign_bl_bin: "bin_sign (bl_to_bin bs) = 0"
   by (simp add: bl_to_bin_def sign_bl_bin')
 
 lemma bl_sbin_sign_aux: "hd (bin_to_bl_aux (Suc n) w bs) = (bin_sign (signed_take_bit n w) = -1)"
   by (induction n arbitrary: w bs) (auto simp add: bin_sign_def even_iff_mod_2_eq_zero bit_Suc)
 
 lemma bl_sbin_sign: "hd (bin_to_bl (Suc n) w) = (bin_sign (signed_take_bit n w) = -1)"
   unfolding bin_to_bl_def by (rule bl_sbin_sign_aux)
 
 lemma bin_nth_of_bl_aux:
   "bit (bl_to_bin_aux bl w) n =
     (n < size bl \<and> rev bl ! n \<or> n \<ge> length bl \<and> bit w (n - size bl))"
   apply (induction bl arbitrary: w)
    apply simp_all
   apply safe
                       apply (simp_all add: not_le nth_append bit_double_iff even_bit_succ_iff split: if_splits)
   done
 
 lemma bin_nth_of_bl: "bit (bl_to_bin bl) n = (n < length bl \<and> rev bl ! n)"
   by (simp add: bl_to_bin_def bin_nth_of_bl_aux)
 
 lemma bin_nth_bl: "n < m \<Longrightarrow> bit w n = nth (rev (bin_to_bl m w)) n"
   apply (induct n arbitrary: m w)
    apply clarsimp
    apply (case_tac m, clarsimp)
    apply (clarsimp simp: bin_to_bl_def)
    apply (simp add: bin_to_bl_aux_alt)
   apply (case_tac m, clarsimp)
   apply (clarsimp simp: bin_to_bl_def)
   apply (simp add: bin_to_bl_aux_alt bit_Suc)
   done
 
 lemma nth_bin_to_bl_aux:
   "n < m + length bl \<Longrightarrow> (bin_to_bl_aux m w bl) ! n =
     (if n < m then bit w (m - 1 - n) else bl ! (n - m))"
   apply (induction bl arbitrary: w)
    apply simp_all
    apply (simp add: bin_nth_bl [of \<open>m - Suc n\<close> m] rev_nth flip: bin_to_bl_def)
    apply (metis One_nat_def Suc_pred add_diff_cancel_left'
      add_diff_cancel_right' bin_to_bl_aux_alt bin_to_bl_def
      diff_Suc_Suc diff_is_0_eq diff_zero less_Suc_eq_0_disj
      less_antisym less_imp_Suc_add list.size(3) nat_less_le nth_append size_bin_to_bl_aux)
   done
 
 lemma nth_bin_to_bl: "n < m \<Longrightarrow> (bin_to_bl m w) ! n = bit w (m - Suc n)"
   by (simp add: bin_to_bl_def nth_bin_to_bl_aux)
 
 lemma takefill_bintrunc: "takefill False n bl = rev (bin_to_bl n (bl_to_bin (rev bl)))"
   apply (rule nth_equalityI)
    apply simp
   apply (clarsimp simp: nth_takefill rev_nth nth_bin_to_bl bin_nth_of_bl)
   done
 
 lemma bl_bin_bl_rtf: "bin_to_bl n (bl_to_bin bl) = rev (takefill False n (rev bl))"
   by (simp add: takefill_bintrunc)
 
 lemma bl_to_bin_lt2p_aux: "bl_to_bin_aux bs w < (w + 1) * (2 ^ length bs)"
 proof (induction bs arbitrary: w)
   case Nil
   then show ?case
     by simp
 next
   case (Cons b bs)
   from Cons.IH [of \<open>1 + 2 * w\<close>] Cons.IH [of \<open>2 * w\<close>]
   show ?case
     apply (auto simp add: algebra_simps)
     apply (subst mult_2 [of \<open>2 ^ length bs\<close>])
     apply (simp only: add.assoc)
     apply (rule pos_add_strict)
      apply simp_all
     done
 qed
 
 lemma bl_to_bin_lt2p_drop: "bl_to_bin bs < 2 ^ length (dropWhile Not bs)"
 proof (induct bs)
   case Nil
   then show ?case by simp
 next
   case (Cons b bs)
   with bl_to_bin_lt2p_aux[where w=1] show ?case
     by (simp add: bl_to_bin_def)
 qed
 
 lemma bl_to_bin_lt2p: "bl_to_bin bs < 2 ^ length bs"
   by (metis bin_bl_bin bintr_lt2p bl_bin_bl)
 
 lemma bl_to_bin_ge2p_aux: "bl_to_bin_aux bs w \<ge> w * (2 ^ length bs)"
 proof (induction bs arbitrary: w)
   case Nil
   then show ?case
     by simp
 next
   case (Cons b bs)
   from Cons.IH [of \<open>1 + 2 * w\<close>] Cons.IH [of \<open>2 * w\<close>]
   show ?case
     apply (auto simp add: algebra_simps)
     apply (rule add_le_imp_le_left [of \<open>2 ^ length bs\<close>])
     apply (rule add_increasing)
     apply simp_all
     done
 qed
 
 lemma bl_to_bin_ge0: "bl_to_bin bs \<ge> 0"
   apply (unfold bl_to_bin_def)
   apply (rule xtrans(4))
    apply (rule bl_to_bin_ge2p_aux)
   apply simp
   done
 
 lemma butlast_rest_bin: "butlast (bin_to_bl n w) = bin_to_bl (n - 1) (w div 2)"
   apply (unfold bin_to_bl_def)
   apply (cases n, clarsimp)
   apply clarsimp
   apply (auto simp add: bin_to_bl_aux_alt)
   done
 
 lemma butlast_bin_rest: "butlast bl = bin_to_bl (length bl - Suc 0) (bl_to_bin bl div 2)"
   using butlast_rest_bin [where w="bl_to_bin bl" and n="length bl"] by simp
 
 lemma butlast_rest_bl2bin_aux:
   "bl \<noteq> [] \<Longrightarrow> bl_to_bin_aux (butlast bl) w = bl_to_bin_aux bl w div 2"
   by (induct bl arbitrary: w) auto
 
 lemma butlast_rest_bl2bin: "bl_to_bin (butlast bl) = bl_to_bin bl div 2"
   by (cases bl) (auto simp: bl_to_bin_def butlast_rest_bl2bin_aux)
 
 lemma trunc_bl2bin_aux:
   "take_bit m (bl_to_bin_aux bl w) =
     bl_to_bin_aux (drop (length bl - m) bl) (take_bit (m - length bl) w)"
 proof (induct bl arbitrary: w)
   case Nil
   show ?case by simp
 next
   case (Cons b bl)
   show ?case
   proof (cases "m - length bl")
     case 0
     then have "Suc (length bl) - m = Suc (length bl - m)" by simp
     with Cons show ?thesis by simp
   next
     case (Suc n)
     then have "m - Suc (length bl) = n" by simp
     with Cons Suc show ?thesis by (simp add: take_bit_Suc ac_simps)
   qed
 qed
 
 lemma trunc_bl2bin: "take_bit m (bl_to_bin bl) = bl_to_bin (drop (length bl - m) bl)"
   by (simp add: bl_to_bin_def trunc_bl2bin_aux)
 
 lemma trunc_bl2bin_len [simp]: "take_bit (length bl) (bl_to_bin bl) = bl_to_bin bl"
   by (simp add: trunc_bl2bin)
 
 lemma bl2bin_drop: "bl_to_bin (drop k bl) = take_bit (length bl - k) (bl_to_bin bl)"
   apply (rule trans)
    prefer 2
    apply (rule trunc_bl2bin [symmetric])
   apply (cases "k \<le> length bl")
    apply auto
   done
 
 lemma take_rest_power_bin: "m \<le> n \<Longrightarrow> take m (bin_to_bl n w) = bin_to_bl m (((\<lambda>w. w div 2) ^^ (n - m)) w)"
   apply (rule nth_equalityI)
    apply simp
   apply (clarsimp simp add: nth_bin_to_bl nth_rest_power_bin)
   done
 
 lemma last_bin_last': "size xs > 0 \<Longrightarrow> last xs \<longleftrightarrow> odd (bl_to_bin_aux xs w)"
   by (induct xs arbitrary: w) auto
 
 lemma last_bin_last: "size xs > 0 \<Longrightarrow> last xs \<longleftrightarrow> odd (bl_to_bin xs)"
   unfolding bl_to_bin_def by (erule last_bin_last')
 
 lemma bin_last_last: "odd w \<longleftrightarrow> last (bin_to_bl (Suc n) w)"
   by (simp add: bin_to_bl_def) (auto simp: bin_to_bl_aux_alt)
 
 lemma drop_bin2bl_aux:
   "drop m (bin_to_bl_aux n bin bs) =
     bin_to_bl_aux (n - m) bin (drop (m - n) bs)"
   apply (induction n arbitrary: m bin bs)
    apply auto
   apply (case_tac "m \<le> n")
    apply (auto simp add: not_le Suc_diff_le)
   apply (case_tac "m - n")
    apply auto
   apply (use Suc_diff_Suc in fastforce)
   done
 
 lemma drop_bin2bl: "drop m (bin_to_bl n bin) = bin_to_bl (n - m) bin"
   by (simp add: bin_to_bl_def drop_bin2bl_aux)
 
 lemma take_bin2bl_lem1: "take m (bin_to_bl_aux m w bs) = bin_to_bl m w"
   apply (induct m arbitrary: w bs)
    apply clarsimp
   apply clarsimp
   apply (simp add: bin_to_bl_aux_alt)
   apply (simp add: bin_to_bl_def)
   apply (simp add: bin_to_bl_aux_alt)
   done
 
 lemma take_bin2bl_lem: "take m (bin_to_bl_aux (m + n) w bs) = take m (bin_to_bl (m + n) w)"
   by (induct n arbitrary: w bs) (simp_all (no_asm) add: bin_to_bl_def take_bin2bl_lem1, simp)
 
 lemma bin_split_take: "bin_split n c = (a, b) \<Longrightarrow> bin_to_bl m a = take m (bin_to_bl (m + n) c)"
   apply (induct n arbitrary: b c)
    apply clarsimp
   apply (clarsimp simp: Let_def split: prod.split_asm)
   apply (simp add: bin_to_bl_def)
   apply (simp add: take_bin2bl_lem drop_bit_Suc)
   done
 
 lemma bin_to_bl_drop_bit:
   "k = m + n \<Longrightarrow> bin_to_bl m (drop_bit n c) = take m (bin_to_bl k c)"
   using bin_split_take by simp
 
 lemma bin_split_take1:
   "k = m + n \<Longrightarrow> bin_split n c = (a, b) \<Longrightarrow> bin_to_bl m a = take m (bin_to_bl k c)"
   using bin_split_take by simp
 
 lemma bl_bin_bl_rep_drop:
   "bin_to_bl n (bl_to_bin bl) =
     replicate (n - length bl) False @ drop (length bl - n) bl"
   by (simp add: bl_to_bin_inj bl_to_bin_rep_F trunc_bl2bin)
 
 lemma bl_to_bin_aux_cat:
   "bl_to_bin_aux bs (concat_bit nv v w) =
     concat_bit (nv + length bs) (bl_to_bin_aux bs v) w"
   by (rule bit_eqI)
     (auto simp add: bin_nth_of_bl_aux bin_nth_cat algebra_simps)
 
 lemma bin_to_bl_aux_cat:
   "bin_to_bl_aux (nv + nw) (concat_bit nw w v) bs =
     bin_to_bl_aux nv v (bin_to_bl_aux nw w bs)"
   by (induction nw arbitrary: w bs) (simp_all add: concat_bit_Suc)
 
 lemma bl_to_bin_aux_alt: "bl_to_bin_aux bs w = concat_bit (length bs) (bl_to_bin bs) w"
   using bl_to_bin_aux_cat [where nv = "0" and v = "0"]
   by (simp add: bl_to_bin_def [symmetric])
 
 lemma bin_to_bl_cat:
   "bin_to_bl (nv + nw) (concat_bit nw w v) =
     bin_to_bl_aux nv v (bin_to_bl nw w)"
   by (simp add: bin_to_bl_def bin_to_bl_aux_cat)
 
 lemmas bl_to_bin_aux_app_cat =
   trans [OF bl_to_bin_aux_append bl_to_bin_aux_alt]
 
 lemmas bin_to_bl_aux_cat_app =
   trans [OF bin_to_bl_aux_cat bin_to_bl_aux_alt]
 
 lemma bl_to_bin_app_cat:
   "bl_to_bin (bsa @ bs) = concat_bit (length bs) (bl_to_bin bs) (bl_to_bin bsa)"
   by (simp only: bl_to_bin_aux_app_cat bl_to_bin_def)
 
 lemma bin_to_bl_cat_app:
   "bin_to_bl (n + nw) (concat_bit nw wa w) = bin_to_bl n w @ bin_to_bl nw wa"
   by (simp only: bin_to_bl_def bin_to_bl_aux_cat_app)
 
 text \<open>\<open>bl_to_bin_app_cat_alt\<close> and \<open>bl_to_bin_app_cat\<close> are easily interderivable.\<close>
 lemma bl_to_bin_app_cat_alt: "concat_bit n w (bl_to_bin cs) = bl_to_bin (cs @ bin_to_bl n w)"
   by (simp add: bl_to_bin_app_cat)
 
 lemma mask_lem: "(bl_to_bin (True # replicate n False)) = bl_to_bin (replicate n True) + 1"
   apply (unfold bl_to_bin_def)
   apply (induct n)
    apply simp
   apply (simp only: Suc_eq_plus1 replicate_add append_Cons [symmetric] bl_to_bin_aux_append)
   apply simp
   done
 
 lemma bin_exhaust:
   "(\<And>x b. bin = of_bool b + 2 * x \<Longrightarrow> Q) \<Longrightarrow> Q" for bin :: int
   apply (cases \<open>even bin\<close>)
    apply (auto elim!: evenE oddE)
    apply fastforce
   apply fastforce
   done
 
 primrec rbl_succ :: "bool list \<Rightarrow> bool list"
   where
     Nil: "rbl_succ Nil = Nil"
   | Cons: "rbl_succ (x # xs) = (if x then False # rbl_succ xs else True # xs)"
 
 primrec rbl_pred :: "bool list \<Rightarrow> bool list"
   where
     Nil: "rbl_pred Nil = Nil"
   | Cons: "rbl_pred (x # xs) = (if x then False # xs else True # rbl_pred xs)"
 
 primrec rbl_add :: "bool list \<Rightarrow> bool list \<Rightarrow> bool list"
   where \<comment> \<open>result is length of first arg, second arg may be longer\<close>
     Nil: "rbl_add Nil x = Nil"
   | Cons: "rbl_add (y # ys) x =
       (let ws = rbl_add ys (tl x)
        in (y \<noteq> hd x) # (if hd x \<and> y then rbl_succ ws else ws))"
 
 primrec rbl_mult :: "bool list \<Rightarrow> bool list \<Rightarrow> bool list"
   where \<comment> \<open>result is length of first arg, second arg may be longer\<close>
     Nil: "rbl_mult Nil x = Nil"
   | Cons: "rbl_mult (y # ys) x =
       (let ws = False # rbl_mult ys x
        in if y then rbl_add ws x else ws)"
 
 lemma size_rbl_pred: "length (rbl_pred bl) = length bl"
   by (induct bl) auto
 
 lemma size_rbl_succ: "length (rbl_succ bl) = length bl"
   by (induct bl) auto
 
 lemma size_rbl_add: "length (rbl_add bl cl) = length bl"
   by (induct bl arbitrary: cl) (auto simp: Let_def size_rbl_succ)
 
 lemma size_rbl_mult: "length (rbl_mult bl cl) = length bl"
   by (induct bl arbitrary: cl) (auto simp add: Let_def size_rbl_add)
 
 lemmas rbl_sizes [simp] =
   size_rbl_pred size_rbl_succ size_rbl_add size_rbl_mult
 
 lemmas rbl_Nils =
   rbl_pred.Nil rbl_succ.Nil rbl_add.Nil rbl_mult.Nil
 
 lemma rbl_add_app2: "length blb \<ge> length bla \<Longrightarrow> rbl_add bla (blb @ blc) = rbl_add bla blb"
   apply (induct bla arbitrary: blb)
    apply simp
   apply clarsimp
   apply (case_tac blb, clarsimp)
   apply (clarsimp simp: Let_def)
   done
 
 lemma rbl_add_take2:
   "length blb \<ge> length bla \<Longrightarrow> rbl_add bla (take (length bla) blb) = rbl_add bla blb"
   apply (induct bla arbitrary: blb)
    apply simp
   apply clarsimp
   apply (case_tac blb, clarsimp)
   apply (clarsimp simp: Let_def)
   done
 
 lemma rbl_mult_app2: "length blb \<ge> length bla \<Longrightarrow> rbl_mult bla (blb @ blc) = rbl_mult bla blb"
   apply (induct bla arbitrary: blb)
    apply simp
   apply clarsimp
   apply (case_tac blb, clarsimp)
   apply (clarsimp simp: Let_def rbl_add_app2)
   done
 
 lemma rbl_mult_take2:
   "length blb \<ge> length bla \<Longrightarrow> rbl_mult bla (take (length bla) blb) = rbl_mult bla blb"
   apply (rule trans)
    apply (rule rbl_mult_app2 [symmetric])
    apply simp
   apply (rule_tac f = "rbl_mult bla" in arg_cong)
   apply (rule append_take_drop_id)
   done
 
 lemma rbl_add_split:
   "P (rbl_add (y # ys) (x # xs)) =
     (\<forall>ws. length ws = length ys \<longrightarrow> ws = rbl_add ys xs \<longrightarrow>
       (y \<longrightarrow> ((x \<longrightarrow> P (False # rbl_succ ws)) \<and> (\<not> x \<longrightarrow> P (True # ws)))) \<and>
       (\<not> y \<longrightarrow> P (x # ws)))"
   by (cases y) (auto simp: Let_def)
 
 lemma rbl_mult_split:
   "P (rbl_mult (y # ys) xs) =
     (\<forall>ws. length ws = Suc (length ys) \<longrightarrow> ws = False # rbl_mult ys xs \<longrightarrow>
       (y \<longrightarrow> P (rbl_add ws xs)) \<and> (\<not> y \<longrightarrow> P ws))"
   by (auto simp: Let_def)
 
 lemma rbl_pred: "rbl_pred (rev (bin_to_bl n bin)) = rev (bin_to_bl n (bin - 1))"
 proof (unfold bin_to_bl_def, induction n arbitrary: bin)
   case 0
   then show ?case
     by simp
 next
   case (Suc n)
   obtain b k where \<open>bin = of_bool b + 2 * k\<close>
     using bin_exhaust by blast
   moreover have \<open>(2 * k - 1) div 2 = k - 1\<close>
     using even_succ_div_2 [of \<open>2 * (k - 1)\<close>]
     by simp
   ultimately show ?case
     using Suc [of \<open>bin div 2\<close>]
     by simp (auto simp add: bin_to_bl_aux_alt)
 qed
 
 lemma rbl_succ: "rbl_succ (rev (bin_to_bl n bin)) = rev (bin_to_bl n (bin + 1))"
   apply (unfold bin_to_bl_def)
   apply (induction n arbitrary: bin)
    apply simp_all
   apply (case_tac bin rule: bin_exhaust)
    apply (simp_all add: bin_to_bl_aux_alt ac_simps)
   done
 
 lemma rbl_add:
   "\<And>bina binb. rbl_add (rev (bin_to_bl n bina)) (rev (bin_to_bl n binb)) =
     rev (bin_to_bl n (bina + binb))"
   apply (unfold bin_to_bl_def)
   apply (induct n)
    apply simp
   apply clarsimp
   apply (case_tac bina rule: bin_exhaust)
   apply (case_tac binb rule: bin_exhaust)
   apply (case_tac b)
    apply (case_tac [!] "ba")
      apply (auto simp: rbl_succ bin_to_bl_aux_alt Let_def ac_simps)
   done
 
 lemma rbl_add_long:
   "m \<ge> n \<Longrightarrow> rbl_add (rev (bin_to_bl n bina)) (rev (bin_to_bl m binb)) =
     rev (bin_to_bl n (bina + binb))"
   apply (rule box_equals [OF _ rbl_add_take2 rbl_add])
    apply (rule_tac f = "rbl_add (rev (bin_to_bl n bina))" in arg_cong)
    apply (rule rev_swap [THEN iffD1])
    apply (simp add: rev_take drop_bin2bl)
   apply simp
   done
 
 lemma rbl_mult_gt1:
   "m \<ge> length bl \<Longrightarrow>
     rbl_mult bl (rev (bin_to_bl m binb)) =
     rbl_mult bl (rev (bin_to_bl (length bl) binb))"
   apply (rule trans)
    apply (rule rbl_mult_take2 [symmetric])
    apply simp_all
   apply (rule_tac f = "rbl_mult bl" in arg_cong)
   apply (rule rev_swap [THEN iffD1])
   apply (simp add: rev_take drop_bin2bl)
   done
 
 lemma rbl_mult_gt:
   "m > n \<Longrightarrow>
     rbl_mult (rev (bin_to_bl n bina)) (rev (bin_to_bl m binb)) =
     rbl_mult (rev (bin_to_bl n bina)) (rev (bin_to_bl n binb))"
   by (auto intro: trans [OF rbl_mult_gt1])
 
 lemmas rbl_mult_Suc = lessI [THEN rbl_mult_gt]
 
 lemma rbbl_Cons: "b # rev (bin_to_bl n x) = rev (bin_to_bl (Suc n) (of_bool b + 2 * x))"
   by (simp add: bin_to_bl_def) (simp add: bin_to_bl_aux_alt)
 
 lemma rbl_mult:
   "rbl_mult (rev (bin_to_bl n bina)) (rev (bin_to_bl n binb)) =
     rev (bin_to_bl n (bina * binb))"
   apply (induct n arbitrary: bina binb)
    apply simp_all
   apply (unfold bin_to_bl_def)
   apply clarsimp
   apply (case_tac bina rule: bin_exhaust)
   apply (case_tac binb rule: bin_exhaust)
   apply (simp_all add: bin_to_bl_aux_alt)
   apply (simp_all add: rbbl_Cons rbl_mult_Suc rbl_add algebra_simps)
   done
 
 lemma sclem: "size (concat (map (bin_to_bl n) xs)) = length xs * n"
   by (simp add: length_concat comp_def sum_list_triv)
 
 lemma bin_cat_foldl_lem:
   "foldl (\<lambda>u k. concat_bit n k u) x xs =
     concat_bit (size xs * n) (foldl (\<lambda>u k. concat_bit n k u) y xs) x"
   apply (induct xs arbitrary: x)
    apply simp
   apply (simp (no_asm))
   apply (frule asm_rl)
   apply (drule meta_spec)
   apply (erule trans)
   apply (drule_tac x = "concat_bit n a y" in meta_spec)
   apply (simp add: bin_cat_assoc_sym)
   done
 
 lemma bin_rcat_bl: "bin_rcat n wl = bl_to_bin (concat (map (bin_to_bl n) wl))"
   apply (unfold bin_rcat_eq_foldl)
   apply (rule sym)
   apply (induct wl)
    apply (auto simp add: bl_to_bin_append)
   apply (simp add: bl_to_bin_aux_alt sclem)
   apply (simp add: bin_cat_foldl_lem [symmetric])
   done
 
 lemma bin_last_bl_to_bin: "odd (bl_to_bin bs) \<longleftrightarrow> bs \<noteq> [] \<and> last bs"
 by(cases "bs = []")(auto simp add: bl_to_bin_def last_bin_last'[where w=0])
 
 lemma bin_rest_bl_to_bin: "bl_to_bin bs div 2 = bl_to_bin (butlast bs)"
 by(cases "bs = []")(simp_all add: bl_to_bin_def butlast_rest_bl2bin_aux)
 
 lemma bl_xor_aux_bin:
   "map2 (\<lambda>x y. x \<noteq> y) (bin_to_bl_aux n v bs) (bin_to_bl_aux n w cs) =
     bin_to_bl_aux n (v XOR w) (map2 (\<lambda>x y. x \<noteq> y) bs cs)"
   apply (induction n arbitrary: v w bs cs)
    apply auto
   apply (case_tac v rule: bin_exhaust)
   apply (case_tac w rule: bin_exhaust)
   apply clarsimp
   done
 
 lemma bl_or_aux_bin:
   "map2 (\<or>) (bin_to_bl_aux n v bs) (bin_to_bl_aux n w cs) =
     bin_to_bl_aux n (v OR w) (map2 (\<or>) bs cs)"
   by (induct n arbitrary: v w bs cs) simp_all
 
 lemma bl_and_aux_bin:
   "map2 (\<and>) (bin_to_bl_aux n v bs) (bin_to_bl_aux n w cs) =
     bin_to_bl_aux n (v AND w) (map2 (\<and>) bs cs)"
   by (induction n arbitrary: v w bs cs) simp_all
 
 lemma bl_not_aux_bin: "map Not (bin_to_bl_aux n w cs) = bin_to_bl_aux n (NOT w) (map Not cs)"
   by (induct n arbitrary: w cs) auto
 
 lemma bl_not_bin: "map Not (bin_to_bl n w) = bin_to_bl n (NOT w)"
   by (simp add: bin_to_bl_def bl_not_aux_bin)
 
 lemma bl_and_bin: "map2 (\<and>) (bin_to_bl n v) (bin_to_bl n w) = bin_to_bl n (v AND w)"
   by (simp add: bin_to_bl_def bl_and_aux_bin)
 
 lemma bl_or_bin: "map2 (\<or>) (bin_to_bl n v) (bin_to_bl n w) = bin_to_bl n (v OR w)"
   by (simp add: bin_to_bl_def bl_or_aux_bin)
 
 lemma bl_xor_bin: "map2 (\<noteq>) (bin_to_bl n v) (bin_to_bl n w) = bin_to_bl n (v XOR w)"
   using bl_xor_aux_bin by (simp add: bin_to_bl_def)
 
 
 subsection \<open>Type \<^typ>\<open>'a word\<close>\<close>
 
 lift_definition of_bl :: \<open>bool list \<Rightarrow> 'a::len word\<close>
   is bl_to_bin .
 
 lift_definition to_bl :: \<open>'a::len word \<Rightarrow> bool list\<close>
   is \<open>bin_to_bl LENGTH('a)\<close>
   by (simp add: bl_to_bin_inj)
 
 lemma to_bl_eq:
   \<open>to_bl w = bin_to_bl (LENGTH('a)) (uint w)\<close>
   for w :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma bit_of_bl_iff [bit_simps]:
   \<open>bit (of_bl bs :: 'a word) n \<longleftrightarrow> rev bs ! n \<and> n < LENGTH('a::len) \<and> n < length bs\<close>
   by transfer (simp add: bin_nth_of_bl ac_simps)
 
 lemma rev_to_bl_eq:
   \<open>rev (to_bl w) = map (bit w) [0..<LENGTH('a)]\<close>
   for w :: \<open>'a::len word\<close>
   apply (rule nth_equalityI)
    apply (simp add: to_bl.rep_eq)
   apply (simp add: bin_nth_bl bit_word.rep_eq to_bl.rep_eq)
   done
 
 lemma to_bl_eq_rev:
   \<open>to_bl w = map (bit w) (rev [0..<LENGTH('a)])\<close>
   for w :: \<open>'a::len word\<close>
   using rev_to_bl_eq [of w]
   apply (subst rev_is_rev_conv [symmetric])
   apply (simp add: rev_map)
   done
 
 lemma of_bl_rev_eq:
   \<open>of_bl (rev bs) = horner_sum of_bool 2 bs\<close>
   apply (rule bit_word_eqI)
   apply (simp add: bit_of_bl_iff)
   apply transfer
   apply (simp add: bit_horner_sum_bit_iff ac_simps)
   done
 
 lemma of_bl_eq:
   \<open>of_bl bs = horner_sum of_bool 2 (rev bs)\<close>
   using of_bl_rev_eq [of \<open>rev bs\<close>] by simp
 
 lemma bshiftr1_eq:
   \<open>bshiftr1 b w = of_bl (b # butlast (to_bl w))\<close>
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps to_bl_eq_rev nth_append rev_nth nth_butlast not_less simp flip: bit_Suc)
   apply (metis Suc_pred len_gt_0 less_eq_decr_length_iff not_bit_length verit_la_disequality)
   done
 
 lemma length_to_bl_eq:
   \<open>length (to_bl w) = LENGTH('a)\<close>
   for w :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma word_rotr_eq:
   \<open>word_rotr n w = of_bl (rotater n (to_bl w))\<close>
   apply (rule bit_word_eqI)
   subgoal for n
     apply (cases \<open>n < LENGTH('a)\<close>)
      apply (simp_all add: bit_word_rotr_iff bit_of_bl_iff rotater_rev length_to_bl_eq nth_rotate rev_to_bl_eq ac_simps)
     done
   done
 
 lemma word_rotl_eq:
   \<open>word_rotl n w = of_bl (rotate n (to_bl w))\<close>
 proof -
   have \<open>rotate n (to_bl w) = rev (rotater n (rev (to_bl w)))\<close>
     by (simp add: rotater_rev')
   then show ?thesis
     apply (simp add: word_rotl_eq_word_rotr bit_of_bl_iff length_to_bl_eq rev_to_bl_eq)
     apply (rule bit_word_eqI)
     subgoal for n
       apply (cases \<open>n < LENGTH('a)\<close>)
        apply (simp_all add: bit_word_rotr_iff bit_of_bl_iff nth_rotater)
       done
     done
 qed
 
 lemma to_bl_def': "(to_bl :: 'a::len word \<Rightarrow> bool list) = bin_to_bl (LENGTH('a)) \<circ> uint"
   by transfer (simp add: fun_eq_iff)
 
 \<comment> \<open>type definitions theorem for in terms of equivalent bool list\<close>
 lemma td_bl:
   "type_definition
     (to_bl :: 'a::len word \<Rightarrow> bool list)
     of_bl
     {bl. length bl = LENGTH('a)}"
   apply (standard; transfer)
   apply (auto dest: sym)
   done
 
 global_interpretation word_bl:
   type_definition
     "to_bl :: 'a::len word \<Rightarrow> bool list"
     of_bl
     "{bl. length bl = LENGTH('a::len)}"
   by (fact td_bl)
 
 lemmas word_bl_Rep' = word_bl.Rep [unfolded mem_Collect_eq, iff]
 
 lemma word_size_bl: "size w = size (to_bl w)"
   by (auto simp: word_size)
 
 lemma to_bl_use_of_bl: "to_bl w = bl \<longleftrightarrow> w = of_bl bl \<and> length bl = length (to_bl w)"
   by (fastforce elim!: word_bl.Abs_inverse [unfolded mem_Collect_eq])
 
 lemma length_bl_gt_0 [iff]: "0 < length (to_bl x)"
   for x :: "'a::len word"
   unfolding word_bl_Rep' by (rule len_gt_0)
 
 lemma bl_not_Nil [iff]: "to_bl x \<noteq> []"
   for x :: "'a::len word"
   by (fact length_bl_gt_0 [unfolded length_greater_0_conv])
 
 lemma length_bl_neq_0 [iff]: "length (to_bl x) \<noteq> 0"
   for x :: "'a::len word"
   by (fact length_bl_gt_0 [THEN gr_implies_not0])
 
+lemma hd_to_bl_iff:
+  \<open>hd (to_bl w) \<longleftrightarrow> bit w (LENGTH('a) - 1)\<close>
+  for w :: \<open>'a::len word\<close>
+  by (simp add: to_bl_eq_rev hd_map hd_rev)
+
 lemma hd_bl_sign_sint: "hd (to_bl w) = (bin_sign (sint w) = -1)"
-  apply transfer
-  apply (auto simp add: bin_sign_def)
-  using bin_sign_lem bl_sbin_sign apply fastforce
-  using bin_sign_lem bl_sbin_sign apply force
-  done
+  by (simp add: hd_to_bl_iff bit_last_iff bin_sign_def)
 
 lemma of_bl_drop':
   "lend = length bl - LENGTH('a::len) \<Longrightarrow>
     of_bl (drop lend bl) = (of_bl bl :: 'a word)"
   by transfer (simp flip: trunc_bl2bin)
 
 lemma test_bit_of_bl:
   "bit (of_bl bl::'a::len word) n = (rev bl ! n \<and> n < LENGTH('a) \<and> n < length bl)"
   by transfer (simp add: bin_nth_of_bl ac_simps)
 
 lemma no_of_bl: "(numeral bin ::'a::len word) = of_bl (bin_to_bl (LENGTH('a)) (numeral bin))"
   by transfer simp
 
 lemma uint_bl: "to_bl w = bin_to_bl (size w) (uint w)"
   by transfer simp
 
 lemma to_bl_bin: "bl_to_bin (to_bl w) = uint w"
   by (simp add: uint_bl word_size)
 
 lemma to_bl_of_bin: "to_bl (word_of_int bin::'a::len word) = bin_to_bl (LENGTH('a)) bin"
   by (auto simp: uint_bl word_ubin.eq_norm word_size)
 
 lemma to_bl_numeral [simp]:
   "to_bl (numeral bin::'a::len word) =
     bin_to_bl (LENGTH('a)) (numeral bin)"
   unfolding word_numeral_alt by (rule to_bl_of_bin)
 
 lemma to_bl_neg_numeral [simp]:
   "to_bl (- numeral bin::'a::len word) =
     bin_to_bl (LENGTH('a)) (- numeral bin)"
   unfolding word_neg_numeral_alt by (rule to_bl_of_bin)
 
 lemma to_bl_to_bin [simp] : "bl_to_bin (to_bl w) = uint w"
   by (simp add: uint_bl word_size)
 
 lemma uint_bl_bin: "bl_to_bin (bin_to_bl (LENGTH('a)) (uint x)) = uint x"
   for x :: "'a::len word"
   by (rule trans [OF bin_bl_bin word_ubin.norm_Rep])
 
 lemma ucast_bl: "ucast w = of_bl (to_bl w)"
   by transfer simp
 
 lemma ucast_down_bl:
   \<open>(ucast :: 'a::len word \<Rightarrow> 'b::len word) (of_bl bl) = of_bl bl\<close>
     if \<open>is_down (ucast :: 'a::len word \<Rightarrow> 'b::len word)\<close>
   using that by transfer simp
 
 lemma of_bl_append_same: "of_bl (X @ to_bl w) = w"
   by transfer (simp add: bl_to_bin_app_cat)
 
 lemma ucast_of_bl_up:
   \<open>ucast (of_bl bl :: 'a::len word) = of_bl bl\<close>
   if \<open>size bl \<le> size (of_bl bl :: 'a::len word)\<close>
   using that
   apply transfer
   apply (rule bit_eqI)
   apply (auto simp add: bit_take_bit_iff)
   apply (subst (asm) trunc_bl2bin_len [symmetric])
   apply (auto simp only: bit_take_bit_iff)
   done
 
 lemma word_rev_tf:
   "to_bl (of_bl bl::'a::len word) =
     rev (takefill False (LENGTH('a)) (rev bl))"
   by transfer (simp add: bl_bin_bl_rtf)
 
 lemma word_rep_drop:
   "to_bl (of_bl bl::'a::len word) =
     replicate (LENGTH('a) - length bl) False @
     drop (length bl - LENGTH('a)) bl"
   by (simp add: word_rev_tf takefill_alt rev_take)
 
 lemma to_bl_ucast:
   "to_bl (ucast (w::'b::len word) ::'a::len word) =
     replicate (LENGTH('a) - LENGTH('b)) False @
     drop (LENGTH('b) - LENGTH('a)) (to_bl w)"
   apply (unfold ucast_bl)
   apply (rule trans)
    apply (rule word_rep_drop)
   apply simp
   done
 
 lemma ucast_up_app:
   \<open>to_bl (ucast w :: 'b::len word) = replicate n False @ (to_bl w)\<close>
     if \<open>source_size (ucast :: 'a word \<Rightarrow> 'b word) + n = target_size (ucast :: 'a word \<Rightarrow> 'b word)\<close>
     for w :: \<open>'a::len word\<close>
   using that
   by (auto simp add : source_size target_size to_bl_ucast)
 
 lemma ucast_down_drop [OF refl]:
   "uc = ucast \<Longrightarrow> source_size uc = target_size uc + n \<Longrightarrow>
     to_bl (uc w) = drop n (to_bl w)"
   by (auto simp add : source_size target_size to_bl_ucast)
 
 lemma scast_down_drop [OF refl]:
   "sc = scast \<Longrightarrow> source_size sc = target_size sc + n \<Longrightarrow>
     to_bl (sc w) = drop n (to_bl w)"
   apply (subgoal_tac "sc = ucast")
    apply safe
    apply simp
    apply (erule ucast_down_drop)
   apply (rule down_cast_same [symmetric])
   apply (simp add : source_size target_size is_down)
   done
 
 lemma word_0_bl [simp]: "of_bl [] = 0"
   by transfer simp
 
 lemma word_1_bl: "of_bl [True] = 1"
   by transfer (simp add: bl_to_bin_def)
 
 lemma of_bl_0 [simp]: "of_bl (replicate n False) = 0"
   by transfer (simp add: bl_to_bin_rep_False)
 
 lemma to_bl_0 [simp]: "to_bl (0::'a::len word) = replicate (LENGTH('a)) False"
   by (simp add: uint_bl word_size bin_to_bl_zero)
 
 \<comment> \<open>links with \<open>rbl\<close> operations\<close>
 lemma word_succ_rbl: "to_bl w = bl \<Longrightarrow> to_bl (word_succ w) = rev (rbl_succ (rev bl))"
   by transfer (simp add: rbl_succ)
 
 lemma word_pred_rbl: "to_bl w = bl \<Longrightarrow> to_bl (word_pred w) = rev (rbl_pred (rev bl))"
   by transfer (simp add: rbl_pred)
 
 lemma word_add_rbl:
   "to_bl v = vbl \<Longrightarrow> to_bl w = wbl \<Longrightarrow>
     to_bl (v + w) = rev (rbl_add (rev vbl) (rev wbl))"
   apply transfer
   apply (drule sym)
   apply (drule sym)
   apply (simp add: rbl_add)
   done
 
 lemma word_mult_rbl:
   "to_bl v = vbl \<Longrightarrow> to_bl w = wbl \<Longrightarrow>
     to_bl (v * w) = rev (rbl_mult (rev vbl) (rev wbl))"
   apply transfer
   apply (drule sym)
   apply (drule sym)
   apply (simp add: rbl_mult)
   done
 
 lemma rtb_rbl_ariths:
   "rev (to_bl w) = ys \<Longrightarrow> rev (to_bl (word_succ w)) = rbl_succ ys"
   "rev (to_bl w) = ys \<Longrightarrow> rev (to_bl (word_pred w)) = rbl_pred ys"
   "rev (to_bl v) = ys \<Longrightarrow> rev (to_bl w) = xs \<Longrightarrow> rev (to_bl (v * w)) = rbl_mult ys xs"
   "rev (to_bl v) = ys \<Longrightarrow> rev (to_bl w) = xs \<Longrightarrow> rev (to_bl (v + w)) = rbl_add ys xs"
   by (auto simp: rev_swap [symmetric] word_succ_rbl word_pred_rbl word_mult_rbl word_add_rbl)
 
 lemma of_bl_length_less:
   \<open>(of_bl x :: 'a::len word) < 2 ^ k\<close>
     if \<open>length x = k\<close> \<open>k < LENGTH('a)\<close>
 proof -
   from that have \<open>length x < LENGTH('a)\<close>
     by simp
   then have \<open>(of_bl x :: 'a::len word) < 2 ^ length x\<close>
     apply (simp add: of_bl_eq)
     apply transfer
     apply (simp add: take_bit_horner_sum_bit_eq)
     apply (subst length_rev [symmetric])
     apply (simp only: horner_sum_of_bool_2_less)
     done
   with that show ?thesis
     by simp
 qed
 
 lemma word_eq_rbl_eq: "x = y \<longleftrightarrow> rev (to_bl x) = rev (to_bl y)"
   by simp
 
 lemma bl_word_not: "to_bl (NOT w) = map Not (to_bl w)"
   by transfer (simp add: bl_not_bin)
 
 lemma bl_word_xor: "to_bl (v XOR w) = map2 (\<noteq>) (to_bl v) (to_bl w)"
   by transfer (simp flip: bl_xor_bin)
 
 lemma bl_word_or: "to_bl (v OR w) = map2 (\<or>) (to_bl v) (to_bl w)"
   by transfer (simp flip: bl_or_bin)
 
 lemma bl_word_and: "to_bl (v AND w) = map2 (\<and>) (to_bl v) (to_bl w)"
   by transfer (simp flip: bl_and_bin)
 
 lemma bin_nth_uint': "bit (uint w) n \<longleftrightarrow> rev (bin_to_bl (size w) (uint w)) ! n \<and> n < size w"
   apply (unfold word_size)
   apply (safe elim!: bin_nth_uint_imp)
    apply (frule bin_nth_uint_imp)
    apply (fast dest!: bin_nth_bl)+
   done
 
 lemmas bin_nth_uint = bin_nth_uint' [unfolded word_size]
 
 lemma test_bit_bl: "bit w n \<longleftrightarrow> rev (to_bl w) ! n \<and> n < size w"
   by transfer (auto simp add: bin_nth_bl)
 
 lemma to_bl_nth: "n < size w \<Longrightarrow> to_bl w ! n = bit w (size w - Suc n)"
   by (simp add: word_size rev_nth test_bit_bl)
 
 lemma map_bit_interval_eq:
   \<open>map (bit w) [0..<n] = takefill False n (rev (to_bl w))\<close> for w :: \<open>'a::len word\<close>
 proof (rule nth_equalityI)
   show \<open>length (map (bit w) [0..<n]) =
     length (takefill False n (rev (to_bl w)))\<close>
     by simp
   fix m
   assume \<open>m < length (map (bit w) [0..<n])\<close>
   then have \<open>m < n\<close>
     by simp
   then have \<open>bit w m \<longleftrightarrow> takefill False n (rev (to_bl w)) ! m\<close>
     by (auto simp add: nth_takefill not_less rev_nth to_bl_nth word_size dest: bit_imp_le_length)
   with \<open>m < n \<close>show \<open>map (bit w) [0..<n] ! m \<longleftrightarrow> takefill False n (rev (to_bl w)) ! m\<close>
     by simp
 qed
 
 lemma to_bl_unfold:
   \<open>to_bl w = rev (map (bit w) [0..<LENGTH('a)])\<close> for w :: \<open>'a::len word\<close>
   by (simp add: map_bit_interval_eq takefill_bintrunc to_bl_def flip: bin_to_bl_def)
 
 lemma nth_rev_to_bl:
   \<open>rev (to_bl w) ! n \<longleftrightarrow> bit w n\<close>
   if \<open>n < LENGTH('a)\<close> for w :: \<open>'a::len word\<close>
   using that by (simp add: to_bl_unfold)
 
 lemma nth_to_bl:
   \<open>to_bl w ! n \<longleftrightarrow> bit w (LENGTH('a) - Suc n)\<close>
   if \<open>n < LENGTH('a)\<close> for w :: \<open>'a::len word\<close>
   using that by (simp add: to_bl_unfold rev_nth)
 
 lemma of_bl_rep_False: "of_bl (replicate n False @ bs) = of_bl bs"
   by (auto simp: of_bl_def bl_to_bin_rep_F)
 
 lemma [code abstract]:
   \<open>Word.the_int (of_bl bs :: 'a word) = horner_sum of_bool 2 (take LENGTH('a::len) (rev bs))\<close>
   apply (simp add: of_bl_eq flip: take_bit_horner_sum_bit_eq)
   apply transfer
   apply simp
   done
 
 lemma [code]:
   \<open>to_bl w = map (bit w) (rev [0..<LENGTH('a::len)])\<close>
   for w :: \<open>'a::len word\<close>
   by (fact to_bl_eq_rev)
 
 lemma word_reverse_eq_of_bl_rev_to_bl:
   \<open>word_reverse w = of_bl (rev (to_bl w))\<close>
   by (rule bit_word_eqI)
     (auto simp add: bit_word_reverse_iff bit_of_bl_iff nth_to_bl)
 
 lemmas word_reverse_no_def [simp] =
   word_reverse_eq_of_bl_rev_to_bl [of "numeral w"] for w
 
 lemma to_bl_word_rev: "to_bl (word_reverse w) = rev (to_bl w)"
   by (rule nth_equalityI) (simp_all add: nth_rev_to_bl word_reverse_def word_rep_drop flip: of_bl_eq)
 
 lemma to_bl_n1 [simp]: "to_bl (-1::'a::len word) = replicate (LENGTH('a)) True"
   apply (rule word_bl.Abs_inverse')
    apply simp
   apply (rule word_eqI)
   apply (clarsimp simp add: word_size)
   apply (auto simp add: word_bl.Abs_inverse test_bit_bl word_size)
   done
 
 lemma rbl_word_or: "rev (to_bl (x OR y)) = map2 (\<or>) (rev (to_bl x)) (rev (to_bl y))"
   by (simp add: zip_rev bl_word_or rev_map)
 
 lemma rbl_word_and: "rev (to_bl (x AND y)) = map2 (\<and>) (rev (to_bl x)) (rev (to_bl y))"
   by (simp add: zip_rev bl_word_and rev_map)
 
 lemma rbl_word_xor: "rev (to_bl (x XOR y)) = map2 (\<noteq>) (rev (to_bl x)) (rev (to_bl y))"
   by (simp add: zip_rev bl_word_xor rev_map)
 
 lemma rbl_word_not: "rev (to_bl (NOT x)) = map Not (rev (to_bl x))"
   by (simp add: bl_word_not rev_map)
 
 lemma bshiftr1_numeral [simp]:
   \<open>bshiftr1 b (numeral w :: 'a word) = of_bl (b # butlast (bin_to_bl LENGTH('a::len) (numeral w)))\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps rev_nth nth_append nth_butlast nth_bin_to_bl simp flip: bit_Suc)
 
 lemma bshiftr1_bl: "to_bl (bshiftr1 b w) = b # butlast (to_bl w)"
   unfolding bshiftr1_eq by (rule word_bl.Abs_inverse) simp
 
 lemma shiftl1_of_bl: "shiftl1 (of_bl bl) = of_bl (bl @ [False])"
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps)
   subgoal for n
     apply (cases n)
      apply simp_all
     done
   done
 
 lemma shiftl1_bl: "shiftl1 w = of_bl (to_bl w @ [False])"
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps)
   subgoal for n
     apply (cases n)
      apply (simp_all add: nth_rev_to_bl)
     done
   done
 
 lemma bl_shiftl1: "to_bl (shiftl1 w) = tl (to_bl w) @ [False]"
   for w :: "'a::len word"
   by (simp add: shiftl1_bl word_rep_drop drop_Suc drop_Cons') (fast intro!: Suc_leI)
 
 lemma to_bl_double_eq:
   \<open>to_bl (2 * w) = tl (to_bl w) @ [False]\<close>
   using bl_shiftl1 [of w] by (simp add: shiftl1_def ac_simps)
 
 \<comment> \<open>Generalized version of \<open>bl_shiftl1\<close>. Maybe this one should replace it?\<close>
 lemma bl_shiftl1': "to_bl (shiftl1 w) = tl (to_bl w @ [False])"
   by (simp add: shiftl1_bl word_rep_drop drop_Suc del: drop_append)
 
 lemma shiftr1_bl:
   \<open>shiftr1 w = of_bl (butlast (to_bl w))\<close>
 proof (rule bit_word_eqI)
   fix n
   assume \<open>n < LENGTH('a)\<close>
   show \<open>bit (shiftr1 w) n \<longleftrightarrow> bit (of_bl (butlast (to_bl w)) :: 'a word) n\<close>
   proof (cases \<open>n = LENGTH('a) - 1\<close>)
     case True
     then show ?thesis
       by (simp add: bit_shiftr1_iff bit_of_bl_iff)
   next
     case False
     with \<open>n < LENGTH('a)\<close>
     have \<open>n < LENGTH('a) - 1\<close>
       by simp
     with \<open>n < LENGTH('a)\<close> show ?thesis
       by (simp add: bit_shiftr1_iff bit_of_bl_iff rev_nth nth_butlast
         word_size to_bl_nth)
   qed
 qed
 
 lemma bl_shiftr1: "to_bl (shiftr1 w) = False # butlast (to_bl w)"
   for w :: "'a::len word"
   by (simp add: shiftr1_bl word_rep_drop len_gt_0 [THEN Suc_leI])
 
 \<comment> \<open>Generalized version of \<open>bl_shiftr1\<close>. Maybe this one should replace it?\<close>
 lemma bl_shiftr1': "to_bl (shiftr1 w) = butlast (False # to_bl w)"
   apply (rule word_bl.Abs_inverse')
    apply (simp del: butlast.simps)
   apply (simp add: shiftr1_bl of_bl_def)
   done
 
 lemma bl_sshiftr1: "to_bl (sshiftr1 w) = hd (to_bl w) # butlast (to_bl w)"
   for w :: "'a::len word"
 proof (rule nth_equalityI)
   fix n
   assume \<open>n < length (to_bl (sshiftr1 w))\<close>
   then have \<open>n < LENGTH('a)\<close>
     by simp
   then show \<open>to_bl (sshiftr1 w) ! n \<longleftrightarrow> (hd (to_bl w) # butlast (to_bl w)) ! n\<close>
     apply (cases n)
      apply (simp_all add: to_bl_nth word_size hd_conv_nth bit_sshiftr1_iff nth_butlast Suc_diff_Suc nth_to_bl)
     done
 qed simp
 
-lemma drop_shiftr: "drop n (to_bl (drop_bit n w)) = take (size w - n) (to_bl w)"
+lemma drop_shiftr: "drop n (to_bl (w >> n)) = take (size w - n) (to_bl w)"
   for w :: "'a::len word"
   apply (rule nth_equalityI)
    apply (simp_all add: word_size to_bl_nth bit_simps)
   done
 
-lemma drop_sshiftr: "drop n (to_bl (signed_drop_bit n w)) = take (size w - n) (to_bl w)"
+lemma drop_sshiftr: "drop n (to_bl (w >>> n)) = take (size w - n) (to_bl w)"
   for w :: "'a::len word"
-   apply (simp_all add: word_size)
   apply (rule nth_equalityI)
-   apply (simp_all add: word_size nth_to_bl bit_signed_drop_bit_iff)
+   apply (simp_all add: word_size nth_to_bl bit_simps)
   done
 
-lemma take_shiftr: "n \<le> size w \<Longrightarrow> take n (to_bl (drop_bit n w)) = replicate n False"
+lemma take_shiftr: "n \<le> size w \<Longrightarrow> take n (to_bl (w >> n)) = replicate n False"
   apply (rule nth_equalityI)
-   apply (simp_all add: word_size to_bl_nth bit_simps)
-  using bit_imp_le_length by fastforce
+   apply (auto simp add: word_size to_bl_nth bit_simps dest: bit_imp_le_length)
+  done
 
 lemma take_sshiftr':
-  "n \<le> size w \<Longrightarrow> hd (to_bl (signed_drop_bit n w)) = hd (to_bl w) \<and>
-    take n (to_bl (signed_drop_bit n w)) = replicate n (hd (to_bl w))"
+  "n \<le> size w \<Longrightarrow> hd (to_bl (w >>> n)) = hd (to_bl w) \<and>
+    take n (to_bl (w >>> n)) = replicate n (hd (to_bl w))"
   for w :: "'a::len word"
-  apply (auto simp add: hd_bl_sign_sint bin_sign_def not_le word_size sint_signed_drop_bit_eq)
+  apply (cases n)
+   apply (auto simp add: hd_to_bl_iff bit_simps not_less word_size)
   apply (rule nth_equalityI)
-    apply (auto simp add: nth_to_bl bit_signed_drop_bit_iff bit_last_iff)
-  apply (rule nth_equalityI)
-   apply (auto simp add: nth_to_bl bit_signed_drop_bit_iff bit_last_iff)
+   apply (auto simp add: nth_to_bl bit_simps nth_Cons split: nat.split)
   done
 
 lemmas hd_sshiftr = take_sshiftr' [THEN conjunct1]
 lemmas take_sshiftr = take_sshiftr' [THEN conjunct2]
 
 lemma atd_lem: "take n xs = t \<Longrightarrow> drop n xs = d \<Longrightarrow> xs = t @ d"
   by (auto intro: append_take_drop_id [symmetric])
 
 lemmas bl_shiftr = atd_lem [OF take_shiftr drop_shiftr]
 lemmas bl_sshiftr = atd_lem [OF take_sshiftr drop_sshiftr]
 
-lemma shiftl_of_bl: "push_bit n (of_bl bl) = of_bl (bl @ replicate n False)"
+lemma shiftl_of_bl: "of_bl bl << n = of_bl (bl @ replicate n False)"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps nth_append)
   done
 
-lemma shiftl_bl: "push_bit n w = of_bl (to_bl w @ replicate n False)"
+lemma shiftl_bl: "w << n = of_bl (to_bl w @ replicate n False)"
   for w :: "'a::len word"
-proof -
-  have "push_bit n w = push_bit n (of_bl (to_bl w))"
-    by simp
-  also have "\<dots> = of_bl (to_bl w @ replicate n False)"
-    by (rule shiftl_of_bl)
-  finally show ?thesis .
-qed
+  by (simp flip: shiftl_of_bl)
 
-lemma bl_shiftl: "to_bl (push_bit n w) = drop n (to_bl w) @ replicate (min (size w) n) False"
+lemma bl_shiftl: "to_bl (w << n) = drop n (to_bl w) @ replicate (min (size w) n) False"
   by (simp add: shiftl_bl word_rep_drop word_size)
 
 lemma shiftr1_bl_of:
   "length bl \<le> LENGTH('a) \<Longrightarrow>
     shiftr1 (of_bl bl::'a::len word) = of_bl (butlast bl)"
   apply (rule bit_word_eqI)
   apply (simp add: bit_simps)
   apply (cases bl rule: rev_cases)
   apply auto
   done
 
 lemma shiftr_bl_of:
   "length bl \<le> LENGTH('a) \<Longrightarrow>
-    drop_bit n (of_bl bl::'a::len word) = of_bl (take (length bl - n) bl)"
+     (of_bl bl::'a::len word) >> n = of_bl (take (length bl - n) bl)"
   by (rule bit_word_eqI) (auto simp add: bit_simps rev_nth)
 
-lemma shiftr_bl: "drop_bit n x \<equiv> of_bl (take (LENGTH('a) - n) (to_bl x))"
+lemma shiftr_bl: "x >> n \<equiv> of_bl (take (LENGTH('a) - n) (to_bl x))"
   for x :: "'a::len word"
   using shiftr_bl_of [where 'a='a, of "to_bl x"] by simp
 
 lemma aligned_bl_add_size [OF refl]:
   "size x - n = m \<Longrightarrow> n \<le> size x \<Longrightarrow> drop m (to_bl x) = replicate n False \<Longrightarrow>
     take m (to_bl y) = replicate m False \<Longrightarrow>
     to_bl (x + y) = take m (to_bl x) @ drop m (to_bl y)" for x :: \<open>'a::len word\<close>
   apply (subgoal_tac "x AND y = 0")
    prefer 2
    apply (rule word_bl.Rep_eqD)
    apply (simp add: bl_word_and)
    apply (rule align_lem_and [THEN trans])
        apply (simp_all add: word_size)[5]
    apply simp
   apply (subst word_plus_and_or [symmetric])
   apply (simp add : bl_word_or)
   apply (rule align_lem_or)
      apply (simp_all add: word_size)
   done
 
 lemma mask_bl: "mask n = of_bl (replicate n True)"
   by (auto simp add: bit_simps intro!: word_eqI)
 
 lemma bl_and_mask':
   "to_bl (w AND mask n :: 'a::len word) =
     replicate (LENGTH('a) - n) False @
     drop (LENGTH('a) - n) (to_bl w)"
   apply (rule nth_equalityI)
    apply simp
   apply (clarsimp simp add: to_bl_nth word_size bit_simps)
   apply (auto simp add: word_size test_bit_bl nth_append rev_nth)
   done
 
 lemma slice1_eq_of_bl:
   \<open>(slice1 n w :: 'b::len word) = of_bl (takefill False n (to_bl w))\<close>
   for w :: \<open>'a::len word\<close>
 proof (rule bit_word_eqI)
   fix m
   assume \<open>m < LENGTH('b)\<close>
   show \<open>bit (slice1 n w :: 'b::len word) m \<longleftrightarrow> bit (of_bl (takefill False n (to_bl w)) :: 'b word) m\<close>
     by (cases \<open>m \<ge> n\<close>; cases \<open>LENGTH('a) \<ge> n\<close>)
       (auto simp add: bit_slice1_iff bit_of_bl_iff not_less rev_nth not_le nth_takefill nth_to_bl algebra_simps)
 qed
 
 lemma slice1_no_bin [simp]:
   "slice1 n (numeral w :: 'b word) = of_bl (takefill False n (bin_to_bl (LENGTH('b::len)) (numeral w)))"
   by (simp add: slice1_eq_of_bl) (* TODO: neg_numeral *)
 
 lemma slice_no_bin [simp]:
   "slice n (numeral w :: 'b word) = of_bl (takefill False (LENGTH('b::len) - n)
     (bin_to_bl (LENGTH('b::len)) (numeral w)))"
   by (simp add: slice_def) (* TODO: neg_numeral *)
 
 lemma slice_take': "slice n w = of_bl (take (size w - n) (to_bl w))"
   by (simp add: slice_def word_size slice1_eq_of_bl takefill_alt)
 
 lemmas slice_take = slice_take' [unfolded word_size]
 
 \<comment> \<open>shiftr to a word of the same size is just slice,
     slice is just shiftr then ucast\<close>
 lemmas shiftr_slice = trans [OF shiftr_bl [THEN meta_eq_to_obj_eq] slice_take [symmetric]]
 
 lemma slice1_down_alt':
   "sl = slice1 n w \<Longrightarrow> fs = size sl \<Longrightarrow> fs + k = n \<Longrightarrow>
     to_bl sl = takefill False fs (drop k (to_bl w))"
   apply (simp add: slice1_eq_of_bl)
   apply transfer
   apply (simp add: bl_bin_bl_rep_drop)
   using drop_takefill
   apply force
   done
 
 lemma slice1_up_alt':
   "sl = slice1 n w \<Longrightarrow> fs = size sl \<Longrightarrow> fs = n + k \<Longrightarrow>
     to_bl sl = takefill False fs (replicate k False @ (to_bl w))"
   apply (simp add: slice1_eq_of_bl)
   apply transfer
   apply (simp add: bl_bin_bl_rep_drop flip: takefill_append)
   apply (metis diff_add_inverse)
   done
 
 lemmas sd1 = slice1_down_alt' [OF refl refl, unfolded word_size]
 lemmas su1 = slice1_up_alt' [OF refl refl, unfolded word_size]
 lemmas slice1_down_alt = le_add_diff_inverse [THEN sd1]
 lemmas slice1_up_alts =
   le_add_diff_inverse [symmetric, THEN su1]
   le_add_diff_inverse2 [symmetric, THEN su1]
 
 lemma slice1_tf_tf':
   "to_bl (slice1 n w :: 'a::len word) =
     rev (takefill False (LENGTH('a)) (rev (takefill False n (to_bl w))))"
   unfolding slice1_eq_of_bl by (rule word_rev_tf)
 
 lemmas slice1_tf_tf = slice1_tf_tf' [THEN word_bl.Rep_inverse', symmetric]
 
 lemma revcast_eq_of_bl:
   \<open>(revcast w :: 'b::len word) = of_bl (takefill False (LENGTH('b)) (to_bl w))\<close>
   for w :: \<open>'a::len word\<close>
   by (simp add: revcast_def slice1_eq_of_bl)
 
 lemmas revcast_no_def [simp] = revcast_eq_of_bl [where w="numeral w", unfolded word_size] for w
 
 lemma to_bl_revcast:
   "to_bl (revcast w :: 'a::len word) = takefill False (LENGTH('a)) (to_bl w)"
   apply (rule nth_equalityI)
   apply simp
   apply (cases \<open>LENGTH('a) \<le> LENGTH('b)\<close>)
    apply (auto simp add: nth_to_bl nth_takefill bit_revcast_iff)
   done
 
 lemma word_cat_bl: "word_cat a b = of_bl (to_bl a @ to_bl b)"
   apply (rule bit_word_eqI)
   apply (simp add: bit_word_cat_iff bit_of_bl_iff nth_append not_less nth_rev_to_bl)
   apply (meson bit_word.rep_eq less_diff_conv2 nth_rev_to_bl)
   done
 
 lemma of_bl_append:
   "(of_bl (xs @ ys) :: 'a::len word) = of_bl xs * 2^(length ys) + of_bl ys"
   apply transfer
   apply (simp add: bl_to_bin_app_cat bin_cat_num)
   done
 
 lemma of_bl_False [simp]: "of_bl (False#xs) = of_bl xs"
   by (rule word_eqI) (auto simp: test_bit_of_bl nth_append)
 
 lemma of_bl_True [simp]: "(of_bl (True # xs) :: 'a::len word) = 2^length xs + of_bl xs"
   by (subst of_bl_append [where xs="[True]", simplified]) (simp add: word_1_bl)
 
 lemma of_bl_Cons: "of_bl (x#xs) = of_bool x * 2^length xs + of_bl xs"
   by (cases x) simp_all
 
 lemma word_split_bl':
   "std = size c - size b \<Longrightarrow> (word_split c = (a, b)) \<Longrightarrow>
     (a = of_bl (take std (to_bl c)) \<and> b = of_bl (drop std (to_bl c)))"
   apply (simp add: word_split_def)
   apply transfer
   apply (cases \<open>LENGTH('b) \<le> LENGTH('a)\<close>)
    apply (auto simp add: drop_bit_take_bit drop_bin2bl bin_to_bl_drop_bit [symmetric, of \<open>LENGTH('a)\<close> \<open>LENGTH('a) - LENGTH('b)\<close> \<open>LENGTH('b)\<close>] min_absorb2)
   done
 
 lemma word_split_bl: "std = size c - size b \<Longrightarrow>
     (a = of_bl (take std (to_bl c)) \<and> b = of_bl (drop std (to_bl c))) \<longleftrightarrow>
     word_split c = (a, b)"
   apply (rule iffI)
    defer
    apply (erule (1) word_split_bl')
   apply (case_tac "word_split c")
   apply (auto simp add: word_size)
   apply (frule word_split_bl' [rotated])
    apply (auto simp add: word_size)
   done
 
 lemma word_split_bl_eq:
   "(word_split c :: ('c::len word \<times> 'd::len word)) =
     (of_bl (take (LENGTH('a::len) - LENGTH('d::len)) (to_bl c)),
      of_bl (drop (LENGTH('a) - LENGTH('d)) (to_bl c)))"
   for c :: "'a::len word"
   apply (rule word_split_bl [THEN iffD1])
    apply (unfold word_size)
    apply (rule refl conjI)+
   done
 
 lemma word_rcat_bl:
   \<open>word_rcat wl = of_bl (concat (map to_bl wl))\<close>
 proof -
   define ws where \<open>ws = rev wl\<close>
   moreover have \<open>word_rcat (rev ws) = of_bl (concat (map to_bl (rev ws)))\<close>
     apply (simp add: word_rcat_def of_bl_eq rev_concat rev_map comp_def rev_to_bl_eq flip: horner_sum_of_bool_2_concat)
     apply transfer
     apply simp
     done
   ultimately show ?thesis
     by simp
 qed
 
 lemma size_rcat_lem': "size (concat (map to_bl wl)) = length wl * size (hd wl)"
   by (induct wl) (auto simp: word_size)
 
 lemmas size_rcat_lem = size_rcat_lem' [unfolded word_size]
 
 lemma nth_rcat_lem:
   "n < length (wl::'a word list) * LENGTH('a::len) \<Longrightarrow>
     rev (concat (map to_bl wl)) ! n =
     rev (to_bl (rev wl ! (n div LENGTH('a)))) ! (n mod LENGTH('a))"
   apply (induct wl)
    apply clarsimp
   apply (clarsimp simp add : nth_append size_rcat_lem)
   apply (simp flip: mult_Suc minus_div_mult_eq_mod add: less_Suc_eq_le not_less)
   apply (metis (no_types, lifting) diff_is_0_eq div_le_mono len_not_eq_0 less_Suc_eq less_mult_imp_div_less nonzero_mult_div_cancel_right not_le nth_Cons_0)
   done
 
 lemma foldl_eq_foldr: "foldl (+) x xs = foldr (+) (x # xs) 0"
   for x :: "'a::comm_monoid_add"
   by (induct xs arbitrary: x) (auto simp: add.assoc)
 
 lemmas word_cat_bl_no_bin [simp] =
   word_cat_bl [where a="numeral a" and b="numeral b", unfolded to_bl_numeral]
   for a b (* FIXME: negative numerals, 0 and 1 *)
 
 lemmas word_split_bl_no_bin [simp] =
   word_split_bl_eq [where c="numeral c", unfolded to_bl_numeral] for c
 
 lemmas word_rot_defs = word_roti_eq_word_rotr_word_rotl word_rotr_eq word_rotl_eq
 
 lemma to_bl_rotl: "to_bl (word_rotl n w) = rotate n (to_bl w)"
   by (simp add: word_rotl_eq to_bl_use_of_bl)
 
 lemmas blrs0 = rotate_eqs [THEN to_bl_rotl [THEN trans]]
 
 lemmas word_rotl_eqs =
   blrs0 [simplified word_bl_Rep' word_bl.Rep_inject to_bl_rotl [symmetric]]
 
 lemma to_bl_rotr: "to_bl (word_rotr n w) = rotater n (to_bl w)"
   by (simp add: word_rotr_eq to_bl_use_of_bl)
 
 lemmas brrs0 = rotater_eqs [THEN to_bl_rotr [THEN trans]]
 
 lemmas word_rotr_eqs =
   brrs0 [simplified word_bl_Rep' word_bl.Rep_inject to_bl_rotr [symmetric]]
 
 declare word_rotr_eqs (1) [simp]
 declare word_rotl_eqs (1) [simp]
 
 lemmas abl_cong = arg_cong [where f = "of_bl"]
 
 end
 
 locale word_rotate
 begin
 
 lemmas word_rot_defs' = to_bl_rotl to_bl_rotr
 
 lemmas blwl_syms [symmetric] = bl_word_not bl_word_and bl_word_or bl_word_xor
 
 lemmas lbl_lbl = trans [OF word_bl_Rep' word_bl_Rep' [symmetric]]
 
 lemmas ths_map2 [OF lbl_lbl] = rotate_map2 rotater_map2
 
 lemmas ths_map [where xs = "to_bl v"] = rotate_map rotater_map for v
 
 lemmas th1s [simplified word_rot_defs' [symmetric]] = ths_map2 ths_map
 
 end
 
 lemmas bl_word_rotl_dt = trans [OF to_bl_rotl rotate_drop_take,
   simplified word_bl_Rep']
 
 lemmas bl_word_rotr_dt = trans [OF to_bl_rotr rotater_drop_take,
   simplified word_bl_Rep']
 
 lemma bl_word_roti_dt':
   "n = nat ((- i) mod int (size (w :: 'a::len word))) \<Longrightarrow>
     to_bl (word_roti i w) = drop n (to_bl w) @ take n (to_bl w)"
   apply (unfold word_roti_eq_word_rotr_word_rotl)
   apply (simp add: bl_word_rotl_dt bl_word_rotr_dt word_size)
   apply safe
    apply (simp add: zmod_zminus1_eq_if)
    apply safe
     apply (simp add: nat_mult_distrib)
    apply (simp add: nat_diff_distrib [OF pos_mod_sign pos_mod_conj
                                       [THEN conjunct2, THEN order_less_imp_le]]
                     nat_mod_distrib)
   apply (simp add: nat_mod_distrib)
   done
 
 lemmas bl_word_roti_dt = bl_word_roti_dt' [unfolded word_size]
 
 lemmas word_rotl_dt = bl_word_rotl_dt [THEN word_bl.Rep_inverse' [symmetric]]
 lemmas word_rotr_dt = bl_word_rotr_dt [THEN word_bl.Rep_inverse' [symmetric]]
 lemmas word_roti_dt = bl_word_roti_dt [THEN word_bl.Rep_inverse' [symmetric]]
 
 lemmas word_rotr_dt_no_bin' [simp] =
   word_rotr_dt [where w="numeral w", unfolded to_bl_numeral] for w
   (* FIXME: negative numerals, 0 and 1 *)
 
 lemmas word_rotl_dt_no_bin' [simp] =
   word_rotl_dt [where w="numeral w", unfolded to_bl_numeral] for w
   (* FIXME: negative numerals, 0 and 1 *)
 
 lemma max_word_bl: "to_bl (- 1::'a::len word) = replicate LENGTH('a) True"
   by (fact to_bl_n1)
 
 lemma to_bl_mask:
   "to_bl (mask n :: 'a::len word) =
   replicate (LENGTH('a) - n) False @
     replicate (min (LENGTH('a)) n) True"
   by (simp add: mask_bl word_rep_drop min_def)
 
 lemma map_replicate_True:
   "n = length xs \<Longrightarrow>
     map (\<lambda>(x,y). x \<and> y) (zip xs (replicate n True)) = xs"
   by (induct xs arbitrary: n) auto
 
 lemma map_replicate_False:
   "n = length xs \<Longrightarrow> map (\<lambda>(x,y). x \<and> y)
     (zip xs (replicate n False)) = replicate n False"
   by (induct xs arbitrary: n) auto
 
 context
   includes bit_operations_syntax
 begin
 
 lemma bl_and_mask:
   fixes w :: "'a::len word"
     and n :: nat
   defines "n' \<equiv> LENGTH('a) - n"
   shows "to_bl (w AND mask n) = replicate n' False @ drop n' (to_bl w)"
 proof -
   note [simp] = map_replicate_True map_replicate_False
   have "to_bl (w AND mask n) = map2 (\<and>) (to_bl w) (to_bl (mask n::'a::len word))"
     by (simp add: bl_word_and)
   also have "to_bl w = take n' (to_bl w) @ drop n' (to_bl w)"
     by simp
   also have "map2 (\<and>) \<dots> (to_bl (mask n::'a::len word)) =
       replicate n' False @ drop n' (to_bl w)"
     unfolding to_bl_mask n'_def by (subst zip_append) auto
   finally show ?thesis .
 qed
 
 lemma drop_rev_takefill:
   "length xs \<le> n \<Longrightarrow>
     drop (n - length xs) (rev (takefill False n (rev xs))) = xs"
   by (simp add: takefill_alt rev_take)
 
 declare bin_to_bl_def [simp]
 
 lemmas of_bl_reasoning = to_bl_use_of_bl of_bl_append
 
 lemma uint_of_bl_is_bl_to_bin_drop:
   "length (dropWhile Not l) \<le> LENGTH('a) \<Longrightarrow> uint (of_bl l :: 'a::len word) = bl_to_bin l"
   apply transfer
   apply (simp add: take_bit_eq_mod)
   apply (rule Divides.mod_less)
    apply (rule bl_to_bin_ge0)
   using bl_to_bin_lt2p_drop apply (rule order.strict_trans2)
   apply simp
   done
 
 corollary uint_of_bl_is_bl_to_bin:
   "length l\<le>LENGTH('a) \<Longrightarrow> uint ((of_bl::bool list\<Rightarrow> ('a :: len) word) l) = bl_to_bin l"
   apply(rule uint_of_bl_is_bl_to_bin_drop)
   using le_trans length_dropWhile_le by blast
 
 lemma bin_to_bl_or:
   "bin_to_bl n (a OR b) = map2 (\<or>) (bin_to_bl n a) (bin_to_bl n b)"
   using bl_or_aux_bin[where n=n and v=a and w=b and bs="[]" and cs="[]"]
   by simp
 
 lemma word_and_1_bl:
   fixes x::"'a::len word"
   shows "(x AND 1) = of_bl [bit x 0]"
   by (simp add: mod_2_eq_odd and_one_eq)
 
 lemma word_1_and_bl:
   fixes x::"'a::len word"
   shows "(1 AND x) = of_bl [bit x 0]"
   by (simp add: mod_2_eq_odd one_and_eq)
 
 lemma of_bl_drop:
   "of_bl (drop n xs) = (of_bl xs AND mask (length xs - n))"
   apply (rule bit_word_eqI)
   apply (auto simp: rev_nth bit_simps cong: rev_conj_cong)
   done
 
 lemma to_bl_1:
   "to_bl (1::'a::len word) = replicate (LENGTH('a) - 1) False @ [True]"
   by (rule nth_equalityI) (auto simp add: to_bl_unfold nth_append rev_nth bit_1_iff not_less not_le)
 
 lemma eq_zero_set_bl:
   "(w = 0) = (True \<notin> set (to_bl w))"
   apply (auto simp add: to_bl_unfold)
   apply (rule bit_word_eqI)
   apply auto
   done
 
 lemma of_drop_to_bl:
   "of_bl (drop n (to_bl x)) = (x AND mask (size x - n))"
   by (simp add: of_bl_drop word_size_bl)
 
 lemma unat_of_bl_length:
   "unat (of_bl xs :: 'a::len word) < 2 ^ (length xs)"
 proof (cases "length xs < LENGTH('a)")
   case True
   then have "(of_bl xs::'a::len word) < 2 ^ length xs"
     by (simp add: of_bl_length_less)
   with True
   show ?thesis
     by (simp add: word_less_nat_alt unat_of_nat)
 next
   case False
   have "unat (of_bl xs::'a::len word) < 2 ^ LENGTH('a)"
     by (simp split: unat_split)
   also
   from False
   have "LENGTH('a) \<le> length xs" by simp
   then have "2 ^ LENGTH('a) \<le> (2::nat) ^ length xs"
     by (rule power_increasing) simp
   finally
   show ?thesis .
 qed
 
 lemma word_msb_alt: "msb w \<longleftrightarrow> hd (to_bl w)"
   for w :: "'a::len word"
   apply (simp add: msb_word_eq)
   apply (subst hd_conv_nth)
    apply simp
   apply (subst nth_to_bl)
    apply simp
   apply simp
   done
 
 lemma word_lsb_last:
   \<open>lsb w \<longleftrightarrow> last (to_bl w)\<close>
   for w :: \<open>'a::len word\<close>
   using nth_to_bl [of \<open>LENGTH('a) - Suc 0\<close> w]
   by (simp add: lsb_odd last_conv_nth)
 
 lemma is_aligned_to_bl:
   "is_aligned (w :: 'a :: len word) n = (True \<notin> set (drop (size w - n) (to_bl w)))"
   by (simp add: is_aligned_mask eq_zero_set_bl bl_and_mask word_size)
 
 lemma is_aligned_replicate:
   fixes w::"'a::len word"
   assumes aligned: "is_aligned w n"
   and          nv: "n \<le> LENGTH('a)"
   shows   "to_bl w = (take (LENGTH('a) - n) (to_bl w)) @ replicate n False"
   apply (rule nth_equalityI)
   using assms apply (simp_all add: nth_append not_less word_size to_bl_nth is_aligned_imp_not_bit)
   done
 
 lemma is_aligned_drop:
   fixes w::"'a::len word"
   assumes "is_aligned w n" "n \<le> LENGTH('a)"
   shows "drop (LENGTH('a) - n) (to_bl w) = replicate n False"
 proof -
   have "to_bl w = take (LENGTH('a) - n) (to_bl w) @ replicate n False"
     by (rule is_aligned_replicate) fact+
   then have "drop (LENGTH('a) - n) (to_bl w) = drop (LENGTH('a) - n) \<dots>" by simp
   also have "\<dots> = replicate n False" by simp
   finally show ?thesis .
 qed
 
 lemma less_is_drop_replicate:
   fixes x::"'a::len word"
   assumes lt: "x < 2 ^ n"
   shows   "to_bl x = replicate (LENGTH('a) - n) False @ drop (LENGTH('a) - n) (to_bl x)"
   by (metis assms bl_and_mask' less_mask_eq)
 
 lemma is_aligned_add_conv:
   fixes off::"'a::len word"
   assumes aligned: "is_aligned w n"
   and        offv: "off < 2 ^ n"
   shows    "to_bl (w + off) =
    (take (LENGTH('a) - n) (to_bl w)) @ (drop (LENGTH('a) - n) (to_bl off))"
 proof cases
   assume nv: "n \<le> LENGTH('a)"
   show ?thesis
   proof (subst aligned_bl_add_size, simp_all only: word_size)
     show "drop (LENGTH('a) - n) (to_bl w) = replicate n False"
       by (subst is_aligned_replicate [OF aligned nv]) (simp add: word_size)
 
     from offv show "take (LENGTH('a) - n) (to_bl off) =
                     replicate (LENGTH('a) - n) False"
       by (subst less_is_drop_replicate, assumption) simp
   qed fact
 next
   assume "\<not> n \<le> LENGTH('a)"
   with offv show ?thesis by (simp add: power_overflow)
 qed
 
 lemma is_aligned_replicateI:
   "to_bl p = addr @ replicate n False \<Longrightarrow> is_aligned (p::'a::len word) n"
   apply (simp add: is_aligned_to_bl word_size)
   apply (subgoal_tac "length addr = LENGTH('a) - n")
    apply (simp add: replicate_not_True)
   apply (drule arg_cong [where f=length])
   apply simp
   done
 
 lemma to_bl_2p:
   "n < LENGTH('a) \<Longrightarrow>
    to_bl ((2::'a::len word) ^ n) =
    replicate (LENGTH('a) - Suc n) False @ True # replicate n False"
   apply (rule nth_equalityI)
    apply (auto simp add: nth_append to_bl_nth word_size bit_simps not_less nth_Cons le_diff_conv)
   subgoal for i
   apply (cases \<open>Suc (i + n) - LENGTH('a)\<close>)
   apply simp_all
     done
   done
 
 lemma xor_2p_to_bl:
   fixes x::"'a::len word"
   shows "to_bl (x XOR 2^n) =
   (if n < LENGTH('a)
    then take (LENGTH('a)-Suc n) (to_bl x) @ (\<not>rev (to_bl x)!n) # drop (LENGTH('a)-n) (to_bl x)
    else to_bl x)"
   apply (auto simp add: to_bl_eq_rev take_map drop_map take_rev drop_rev bit_simps)
   apply (rule nth_equalityI)
    apply (auto simp add: bit_simps rev_nth nth_append Suc_diff_Suc)
   done
 
 lemma is_aligned_replicateD:
   "\<lbrakk> is_aligned (w::'a::len word) n; n \<le> LENGTH('a) \<rbrakk>
      \<Longrightarrow> \<exists>xs. to_bl w = xs @ replicate n False
                \<and> length xs = size w - n"
   apply (subst is_aligned_replicate, assumption+)
   apply (rule exI, rule conjI, rule refl)
   apply (simp add: word_size)
   done
 
 text \<open>right-padding a word to a certain length\<close>
 
 definition
   "bl_pad_to bl sz \<equiv> bl @ (replicate (sz - length bl) False)"
 
 lemma bl_pad_to_length:
   assumes lbl: "length bl \<le> sz"
   shows   "length (bl_pad_to bl sz) = sz"
   using lbl by (simp add: bl_pad_to_def)
 
 lemma bl_pad_to_prefix:
   "prefix bl (bl_pad_to bl sz)"
   by (simp add: bl_pad_to_def)
 
 
 lemma of_bl_length:
   "length xs < LENGTH('a) \<Longrightarrow> of_bl xs < (2 :: 'a::len word) ^ length xs"
   by (simp add: of_bl_length_less)
 
 lemma of_bl_mult_and_not_mask_eq:
   "\<lbrakk>is_aligned (a :: 'a::len word) n; length b + m \<le> n\<rbrakk>
    \<Longrightarrow> a + of_bl b * (2^m) AND NOT(mask n) = a"
   apply (simp flip: push_bit_eq_mult subtract_mask(1) take_bit_eq_mask)
   apply (subst disjunctive_add)
    apply (auto simp add: bit_simps not_le not_less)
    apply (meson is_aligned_imp_not_bit is_aligned_weaken less_diff_conv2)
   apply (erule is_alignedE')
   apply (simp add: take_bit_push_bit)
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps)
   done
 
 lemma bin_to_bl_of_bl_eq:
   "\<lbrakk>is_aligned (a::'a::len word) n; length b + c \<le> n; length b + c < LENGTH('a)\<rbrakk>
-  \<Longrightarrow> bin_to_bl (length b) (uint (drop_bit c (a + of_bl b * 2^c))) = b"
+  \<Longrightarrow> bin_to_bl (length b) (uint ((a + of_bl b * 2^c) >> c)) = b"
   apply (simp flip: push_bit_eq_mult take_bit_eq_mask)
   apply (subst disjunctive_add)
    apply (auto simp add: bit_simps not_le not_less unsigned_or_eq unsigned_drop_bit_eq
      unsigned_push_bit_eq bin_to_bl_or simp flip: bin_to_bl_def)
    apply (meson is_aligned_imp_not_bit is_aligned_weaken less_diff_conv2)
   apply (erule is_alignedE')
   apply (rule nth_equalityI)
    apply (auto simp add: nth_bin_to_bl bit_simps rev_nth simp flip: bin_to_bl_def)
   done
 
-(* FIXME: move to Word distribution *)
-lemma bin_nth_minus_Bit0[simp]:
-  "0 < n \<Longrightarrow> bit (numeral (num.Bit0 w) :: int) n = bit (numeral w :: int) (n - 1)"
-  by (cases n; simp)
-
-lemma bin_nth_minus_Bit1[simp]:
-  "0 < n \<Longrightarrow> bit (numeral (num.Bit1 w) :: int) n = bit (numeral w :: int) (n - 1)"
-  by (cases n; simp)
-
 (* casting a long word to a shorter word and casting back to the long word
    is equal to the original long word -- if the word is small enough.
   'l is the longer word.
   's is the shorter word.
 *)
 lemma bl_cast_long_short_long_ingoreLeadingZero_generic:
   "\<lbrakk> length (dropWhile Not (to_bl w)) \<le> LENGTH('s); LENGTH('s) \<le> LENGTH('l) \<rbrakk> \<Longrightarrow>
    (of_bl :: _ \<Rightarrow> 'l::len word) (to_bl ((of_bl::_ \<Rightarrow> 's::len word) (to_bl w))) = w"
   by (rule word_uint_eqI) (simp add: uint_of_bl_is_bl_to_bin uint_of_bl_is_bl_to_bin_drop)
 
 (*
  Casting between longer and shorter word.
   'l is the longer word.
   's is the shorter word.
  For example: 'l::len word is 128 word (full ipv6 address)
               's::len word is 16 word (address piece of ipv6 address in colon-text-representation)
 *)
 corollary ucast_short_ucast_long_ingoreLeadingZero:
   "\<lbrakk> length (dropWhile Not (to_bl w)) \<le> LENGTH('s); LENGTH('s) \<le> LENGTH('l) \<rbrakk> \<Longrightarrow>
    (ucast:: 's::len word \<Rightarrow> 'l::len word) ((ucast:: 'l::len word \<Rightarrow> 's::len word) w) = w"
   apply (subst ucast_bl)+
   apply (rule bl_cast_long_short_long_ingoreLeadingZero_generic; simp)
   done
 
 lemma length_drop_mask:
   fixes w::"'a::len word"
   shows "length (dropWhile Not (to_bl (w AND mask n))) \<le> n"
 proof -
   have "length (takeWhile Not (replicate n False @ ls)) = n + length (takeWhile Not ls)"
     for ls n by(subst takeWhile_append2) simp+
   then show ?thesis
     unfolding bl_and_mask by (simp add: dropWhile_eq_drop)
 qed
 
 lemma map_bits_rev_to_bl:
   "map (bit x) [0..<size x] = rev (to_bl x)"
   by (auto simp: list_eq_iff_nth_eq test_bit_bl word_size)
 
 lemma of_bl_length2:
   "length xs + c < LENGTH('a) \<Longrightarrow> of_bl xs * 2^c < (2::'a::len word) ^ (length xs + c)"
   by (simp add: of_bl_length word_less_power_trans2)
 
 lemma of_bl_max:
   "(of_bl xs :: 'a::len word) \<le> mask (length xs)"
 proof -
   define ys where \<open>ys = rev xs\<close>
   have \<open>take_bit (length ys) (horner_sum of_bool 2 ys :: 'a word) = horner_sum of_bool 2 ys\<close>
     by transfer (simp add: take_bit_horner_sum_bit_eq min_def)
   then have \<open>(of_bl (rev ys) :: 'a word) \<le> mask (length ys)\<close>
     by (simp only: of_bl_rev_eq less_eq_mask_iff_take_bit_eq_self)
   with ys_def show ?thesis
     by simp
 qed
 
 text\<open>Some auxiliaries for sign-shifting by the entire word length or more\<close>
 
 lemma sshiftr_clamp_pos:
   assumes
     "LENGTH('a) \<le> n"
     "0 \<le> sint x"
-  shows "signed_drop_bit n (x::'a::len word) = 0"
-  apply (rule word_sint.Rep_eqD)
-  apply (simp add: sint_signed_drop_bit_eq)
+  shows "(x::'a::len word) >>> n = 0"
+  apply (rule bit_word_eqI)
   using assms
-  by (metis Word.sint_0 bit_last_iff not_less signed_drop_bit_beyond sint_signed_drop_bit_eq) 
+  apply (auto simp add: bit_simps bit_last_iff)
+  done
 
 lemma sshiftr_clamp_neg:
   assumes
     "LENGTH('a) \<le> n"
     "sint x < 0"
-  shows "signed_drop_bit n (x::'a::len word) = -1"
-  apply (rule word_sint.Rep_eqD)
-  apply (simp add: sint_signed_drop_bit_eq)
+  shows "(x::'a::len word) >>> n = -1"
+  apply (rule bit_word_eqI)
   using assms
-  by (metis bit_last_iff signed_drop_bit_beyond sint_n1 sint_signed_drop_bit_eq) 
+  apply (auto simp add: bit_simps bit_last_iff)
+  done
 
 lemma sshiftr_clamp:
   assumes "LENGTH('a) \<le> n"
-  shows "signed_drop_bit n (x::'a::len word) = signed_drop_bit LENGTH('a) x"
-  apply (cases "0 \<le> sint x")
-  subgoal
-    apply (subst sshiftr_clamp_pos[OF assms])
-    defer apply (subst sshiftr_clamp_pos)
-    by auto
-  apply (subst sshiftr_clamp_neg[OF assms])
-  defer apply (subst sshiftr_clamp_neg)
-  by auto
+  shows "(x::'a::len word) >>> n = x >>> LENGTH('a)"
+  apply (rule bit_word_eqI)
+  using assms
+  apply (auto simp add: bit_simps bit_last_iff)
+  done
 
 text\<open>
 Like @{thm shiftr1_bl_of}, but the precondition is stronger because we need to pick the msb out of
 the list.
 \<close>
 lemma sshiftr1_bl_of:
   "length bl = LENGTH('a) \<Longrightarrow>
     sshiftr1 (of_bl bl::'a::len word) = of_bl (hd bl # butlast bl)"
   apply (rule word_bl.Rep_eqD)
   apply (subst bl_sshiftr1[of "of_bl bl :: 'a word"])
   by (simp add: word_bl.Abs_inverse)
 
 text\<open>
 Like @{thm sshiftr1_bl_of}, with a weaker precondition.
 We still get a direct equation for @{term \<open>sshiftr1 (of_bl bl)\<close>}, it's just uglier.
 \<close>
 lemma sshiftr1_bl_of':
   "LENGTH('a) \<le> length bl \<Longrightarrow>
     sshiftr1 (of_bl bl::'a::len word) =
     of_bl (hd (drop (length bl - LENGTH('a)) bl) # butlast (drop (length bl - LENGTH('a)) bl))"
   apply (subst of_bl_drop'[symmetric, of "length bl - LENGTH('a)"])
   using sshiftr1_bl_of[of "drop (length bl - LENGTH('a)) bl"]
   by auto
 
 text\<open>
 Like @{thm shiftr_bl_of}.
 \<close>
 lemma sshiftr_bl_of:
   assumes "length bl = LENGTH('a)"
-  shows "signed_drop_bit n (of_bl bl::'a::len word) = of_bl (replicate n (hd bl) @ take (length bl - n) bl)"
+  shows "(of_bl bl::'a::len word) >>> n = of_bl (replicate n (hd bl) @ take (length bl - n) bl)"
 proof -
   from assms obtain b bs where \<open>bl = b # bs\<close>
     by (cases bl) simp_all
   then have *: \<open>bl ! 0 \<longleftrightarrow> b\<close> \<open>hd bl \<longleftrightarrow> b\<close>
     by simp_all
   show ?thesis
   apply (rule bit_word_eqI)
     using assms * by (auto simp add: bit_simps nth_append rev_nth not_less)
 qed
 
 text\<open>Like @{thm shiftr_bl}\<close>
-lemma sshiftr_bl: "signed_drop_bit n x \<equiv> of_bl (replicate n (msb x) @ take (LENGTH('a) - n) (to_bl x))"
+lemma sshiftr_bl: "x >>> n \<equiv> of_bl (replicate n (msb x) @ take (LENGTH('a) - n) (to_bl x))"
   for x :: "'a::len word"
   unfolding word_msb_alt
   by (smt (z3) length_to_bl_eq sshiftr_bl_of word_bl.Rep_inverse)
 
 end
 
+lemma of_bl_drop_eq_take_bit:
+  \<open>of_bl (drop n xs) = take_bit (length xs - n) (of_bl xs)\<close>
+  by (simp add: of_bl_drop take_bit_eq_mask)
+
+lemma of_bl_take_to_bl_eq_drop_bit:
+  \<open>of_bl (take n (to_bl w)) = drop_bit (LENGTH('a) - n) w\<close>
+    if \<open>n \<le> LENGTH('a)\<close>
+    for w :: \<open>'a::len word\<close>
+  using that shiftr_bl [of w \<open>LENGTH('a) - n\<close>] by (simp add: shiftr_def)
+
 end
diff --git a/thys/Word_Lib/Rsplit.thy b/thys/Word_Lib/Rsplit.thy
--- a/thys/Word_Lib/Rsplit.thy
+++ b/thys/Word_Lib/Rsplit.thy
@@ -1,168 +1,163 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 (* Author: Jeremy Dawson and Gerwin Klein, NICTA *)
 
 section \<open>Splitting words into lists\<close>
 
 theory Rsplit
   imports "HOL-Library.Word" More_Word Bits_Int
 begin
 
 definition word_rsplit :: "'a::len word \<Rightarrow> 'b::len word list"
   where "word_rsplit w = map word_of_int (bin_rsplit LENGTH('b) (LENGTH('a), uint w))"
 
 lemma word_rsplit_no:
   "(word_rsplit (numeral bin :: 'b::len word) :: 'a word list) =
     map word_of_int (bin_rsplit (LENGTH('a::len))
       (LENGTH('b), take_bit (LENGTH('b)) (numeral bin)))"
   by (simp add: word_rsplit_def of_nat_take_bit)
 
 lemmas word_rsplit_no_cl [simp] = word_rsplit_no
   [unfolded bin_rsplitl_def bin_rsplit_l [symmetric]]
 
 text \<open>
   This odd result arises from the fact that the statement of the
   result implies that the decoded words are of the same type,
   and therefore of the same length, as the original word.\<close>
 
 lemma word_rsplit_same: "word_rsplit w = [w]"
   apply (simp add: word_rsplit_def bin_rsplit_all)
   apply transfer
   apply simp
   done
 
 lemma word_rsplit_empty_iff_size: "word_rsplit w = [] \<longleftrightarrow> size w = 0"
   by (simp add: word_rsplit_def bin_rsplit_def word_size bin_rsplit_aux_simp_alt Let_def
       split: prod.split)
 
 lemma test_bit_rsplit:
   "sw = word_rsplit w \<Longrightarrow> m < size (hd sw) \<Longrightarrow>
     k < length sw \<Longrightarrow> bit (rev sw ! k) m = bit w (k * size (hd sw) + m)"
   for sw :: "'a::len word list"
   apply (unfold word_rsplit_def word_test_bit_def)
   apply (rule trans)
    apply (rule_tac f = "\<lambda>x. bit x m" in arg_cong)
    apply (rule nth_map [symmetric])
    apply simp
   apply (rule bin_nth_rsplit)
      apply simp_all
   apply (simp add : word_size rev_map)
   apply (rule trans)
    defer
    apply (rule map_ident [THEN fun_cong])
   apply (rule refl [THEN map_cong])
   apply (simp add: unsigned_of_int take_bit_int_eq_self_iff)
   using bin_rsplit_size_sign take_bit_int_eq_self_iff by blast
 
 lemma test_bit_rsplit_alt:
   \<open>bit ((word_rsplit w  :: 'b::len word list) ! i) m \<longleftrightarrow>
     bit w ((length (word_rsplit w :: 'b::len word list) - Suc i) * size (hd (word_rsplit w :: 'b::len word list)) + m)\<close>
   if \<open>i < length (word_rsplit w :: 'b::len word list)\<close> \<open>m < size (hd (word_rsplit w :: 'b::len word list))\<close> \<open>0 < length (word_rsplit w :: 'b::len word list)\<close>
   for w :: \<open>'a::len word\<close>
   apply (rule trans)
    apply (rule test_bit_cong)
    apply (rule rev_nth [of _ \<open>rev (word_rsplit w)\<close>, simplified rev_rev_ident])
   apply simp
    apply (rule that(1))
   apply simp
   apply (rule test_bit_rsplit)
     apply (rule refl)
   apply (rule asm_rl)
    apply (rule that(2))
   apply (rule diff_Suc_less)
   apply (rule that(3))
   done
 
 lemma word_rsplit_len_indep [OF refl refl refl refl]:
   "[u,v] = p \<Longrightarrow> [su,sv] = q \<Longrightarrow> word_rsplit u = su \<Longrightarrow>
     word_rsplit v = sv \<Longrightarrow> length su = length sv"
   by (auto simp: word_rsplit_def bin_rsplit_len_indep)
 
 lemma length_word_rsplit_size:
   "n = LENGTH('a::len) \<Longrightarrow>
     length (word_rsplit w :: 'a word list) \<le> m \<longleftrightarrow> size w \<le> m * n"
   by (auto simp: word_rsplit_def word_size bin_rsplit_len_le)
 
 lemmas length_word_rsplit_lt_size =
   length_word_rsplit_size [unfolded Not_eq_iff linorder_not_less [symmetric]]
 
 lemma length_word_rsplit_exp_size:
   "n = LENGTH('a::len) \<Longrightarrow>
     length (word_rsplit w :: 'a word list) = (size w + n - 1) div n"
   by (auto simp: word_rsplit_def word_size bin_rsplit_len)
 
 lemma length_word_rsplit_even_size:
   "n = LENGTH('a::len) \<Longrightarrow> size w = m * n \<Longrightarrow>
     length (word_rsplit w :: 'a word list) = m"
   by (cases \<open>LENGTH('a)\<close>) (simp_all add: length_word_rsplit_exp_size div_nat_eqI)
 
 lemmas length_word_rsplit_exp_size' = refl [THEN length_word_rsplit_exp_size]
 
 \<comment> \<open>alternative proof of \<open>word_rcat_rsplit\<close>\<close>
 lemmas tdle = times_div_less_eq_dividend
 lemmas dtle = xtrans(4) [OF tdle mult.commute]
 
 lemma word_rcat_rsplit: "word_rcat (word_rsplit w) = w"
   apply (rule word_eqI)
   apply (clarsimp simp: test_bit_rcat word_size)
   apply (subst refl [THEN test_bit_rsplit])
     apply (simp_all add: word_size
       refl [THEN length_word_rsplit_size [simplified not_less [symmetric], simplified]])
    apply safe
    apply (erule xtrans(7), rule dtle)+
   done
 
 lemma size_word_rsplit_rcat_size:
   "word_rcat ws = frcw \<Longrightarrow> size frcw = length ws * LENGTH('a)
     \<Longrightarrow> length (word_rsplit frcw::'a word list) = length ws"
   for ws :: "'a::len word list" and frcw :: "'b::len word"
   by (cases \<open>LENGTH('a)\<close>) (simp_all add: word_size length_word_rsplit_exp_size' div_nat_eqI)
 
-lemma msrevs:
-  "0 < n \<Longrightarrow> (k * n + m) div n = m div n + k"
-  "(k * n + m) mod n = m mod n"
-  for n :: nat
-  by (auto simp: add.commute)
-
 lemma word_rsplit_rcat_size [OF refl]:
   "word_rcat ws = frcw \<Longrightarrow>
     size frcw = length ws * LENGTH('a) \<Longrightarrow> word_rsplit frcw = ws"
   for ws :: "'a::len word list"
   apply (frule size_word_rsplit_rcat_size, assumption)
   apply (clarsimp simp add : word_size)
   apply (rule nth_equalityI, assumption)
   apply clarsimp
   apply (rule word_eqI [rule_format])
   apply (rule trans)
    apply (rule test_bit_rsplit_alt)
      apply (clarsimp simp: word_size)+
   apply (rule trans)
    apply (rule test_bit_rcat [OF refl refl])
   apply (simp add: word_size)
   apply (subst rev_nth)
    apply arith
   apply (simp add: le0 [THEN [2] xtrans(7), THEN diff_Suc_less])
   apply safe
   apply (simp add: diff_mult_distrib)
    apply (cases "size ws")
     apply simp_all
   done
 
 lemma word_rsplit_upt:
   "\<lbrakk> size x = LENGTH('a :: len) * n; n \<noteq> 0 \<rbrakk>
-    \<Longrightarrow> word_rsplit x = map (\<lambda>i. ucast (drop_bit (i * LENGTH('a)) x) :: 'a word) (rev [0 ..< n])"
+    \<Longrightarrow> word_rsplit x = map (\<lambda>i. ucast (x >> (i * LENGTH('a))) :: 'a word) (rev [0 ..< n])"
   apply (subgoal_tac "length (word_rsplit x :: 'a word list) = n")
    apply (rule nth_equalityI, simp)
    apply (intro allI word_eqI impI)
    apply (simp add: test_bit_rsplit_alt word_size)
    apply (simp add: nth_ucast bit_simps rev_nth field_simps)
-  apply (simp add: length_word_rsplit_exp_size)
-  apply transfer
-  apply (metis (no_types, lifting) Nat.add_diff_assoc Suc_leI add_0_left diff_Suc_less div_less len_gt_0 msrevs(1) mult.commute)
+  apply (simp add: length_word_rsplit_exp_size word_size)
+  apply (subst diff_add_assoc)
+   apply (simp flip: less_eq_Suc_le)
+  apply simp
   done
 
 end
\ No newline at end of file
diff --git a/thys/Word_Lib/Signed_Division_Word.thy b/thys/Word_Lib/Signed_Division_Word.thy
--- a/thys/Word_Lib/Signed_Division_Word.thy
+++ b/thys/Word_Lib/Signed_Division_Word.thy
@@ -1,175 +1,271 @@
 (*
  * Copyright Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section \<open>Signed division on word\<close>
 
 theory Signed_Division_Word
   imports "HOL-Library.Signed_Division" "HOL-Library.Word"
 begin
 
+lemma minus_sdiv_eq [simp]:
+  \<open>- k sdiv l = - (k sdiv l)\<close> for k l :: int
+  by (simp add: signed_divide_int_def)
+
+lemma sdiv_minus_eq [simp]:
+  \<open>k sdiv - l = - (k sdiv l)\<close> for k l :: int
+  by (simp add: signed_divide_int_def)
+
+lemma sdiv_int_numeral_numeral [simp]:
+  \<open>numeral m sdiv numeral n = numeral m div (numeral n :: int)\<close>
+  by (simp add: signed_divide_int_def)
+
+lemma minus_smod_eq [simp]:
+  \<open>- k smod l = - (k smod l)\<close> for k l :: int
+  by (simp add: smod_int_alt_def)
+
+lemma smod_minus_eq [simp]:
+  \<open>k smod - l = k smod l\<close> for k l :: int
+  by (simp add: smod_int_alt_def)
+
+lemma smod_int_numeral_numeral [simp]:
+  \<open>numeral m smod numeral n = numeral m mod (numeral n :: int)\<close>
+  by (simp add: smod_int_alt_def) 
+
 instantiation word :: (len) signed_division
 begin
 
 lift_definition signed_divide_word :: \<open>'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>
   is \<open>\<lambda>k l. signed_take_bit (LENGTH('a) - Suc 0) k sdiv signed_take_bit (LENGTH('a) - Suc 0) l\<close>
   by (simp flip: signed_take_bit_decr_length_iff)
 
 lift_definition signed_modulo_word :: \<open>'a::len word \<Rightarrow> 'a word \<Rightarrow> 'a word\<close>
   is \<open>\<lambda>k l. signed_take_bit (LENGTH('a) - Suc 0) k smod signed_take_bit (LENGTH('a) - Suc 0) l\<close>
   by (simp flip: signed_take_bit_decr_length_iff)
 
 instance ..
 
 end
 
 lemma sdiv_word_def [code]:
   \<open>v sdiv w = word_of_int (sint v sdiv sint w)\<close>
   for v w :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma smod_word_def [code]:
   \<open>v smod w = word_of_int (sint v smod sint w)\<close>
   for v w :: \<open>'a::len word\<close>
   by transfer simp
 
 lemma sdiv_smod_id:
   \<open>(a sdiv b) * b + (a smod b) = a\<close>
   for a b :: \<open>'a::len word\<close>
   by (cases \<open>sint a < 0\<close>; cases \<open>sint b < 0\<close>) (simp_all add: signed_modulo_int_def sdiv_word_def smod_word_def)
 
 lemma signed_div_arith:
     "sint ((a::('a::len) word) sdiv b) = signed_take_bit (LENGTH('a) - 1) (sint a sdiv sint b)"
   apply transfer
   apply simp
   done
 
 lemma signed_mod_arith:
     "sint ((a::('a::len) word) smod b) = signed_take_bit (LENGTH('a) - 1) (sint a smod sint b)"
   apply transfer
   apply simp
   done
 
+lemma word_sdiv_div0 [simp]:
+    "(a :: ('a::len) word) sdiv 0 = 0"
+  apply (auto simp: sdiv_word_def signed_divide_int_def sgn_if)
+  done
+
+lemma smod_word_zero [simp]:
+  \<open>w smod 0 = w\<close> for w :: \<open>'a::len word\<close>
+  by (simp add: smod_word_def signed_modulo_int_def)
+
 lemma word_sdiv_div1 [simp]:
     "(a :: ('a::len) word) sdiv 1 = a"
   apply (cases \<open>LENGTH('a)\<close>)
   apply simp_all
   apply transfer
   apply simp
   apply (case_tac nat)
    apply simp_all
   apply (simp add: take_bit_signed_take_bit)
   done
 
-lemma word_sdiv_div0 [simp]:
-    "(a :: ('a::len) word) sdiv 0 = 0"
-  apply (auto simp: sdiv_word_def signed_divide_int_def sgn_if)
-  done
+lemma smod_word_one [simp]:
+  \<open>w smod 1 = 0\<close> for w :: \<open>'a::len word\<close>
+  by (simp add: smod_word_def signed_modulo_int_def)
 
 lemma word_sdiv_div_minus1 [simp]:
     "(a :: ('a::len) word) sdiv -1 = -a"
   apply (auto simp: sdiv_word_def signed_divide_int_def sgn_if)
   apply transfer
   apply simp
   apply (metis Suc_pred len_gt_0 signed_take_bit_eq_iff_take_bit_eq signed_take_bit_of_0 take_bit_of_0)
   done
 
+lemma smod_word_minus_one [simp]:
+  \<open>w smod - 1 = 0\<close> for w :: \<open>'a::len word\<close>
+  by (simp add: smod_word_def signed_modulo_int_def)
+
+lemma one_sdiv_word_eq [simp]:
+  \<open>1 sdiv w = of_bool (w = 1 \<or> w = - 1) * w\<close> for w :: \<open>'a::len word\<close>
+proof (cases \<open>1 < \<bar>sint w\<bar>\<close>)
+  case True
+  then show ?thesis
+    by (auto simp add: sdiv_word_def signed_divide_int_def split: if_splits)
+next
+  case False
+  then have \<open>\<bar>sint w\<bar> \<le> 1\<close>
+    by simp
+  then have \<open>sint w \<in> {- 1, 0, 1}\<close>
+    by auto
+  then have \<open>(word_of_int (sint w) :: 'a::len word) \<in> word_of_int ` {- 1, 0, 1}\<close>
+    by blast
+  then have \<open>w \<in> {- 1, 0, 1}\<close>
+    by simp
+  then show ?thesis by auto
+qed
+
+lemma one_smod_word_eq [simp]:
+  \<open>1 smod w = 1 - of_bool (w = 1 \<or> w = - 1)\<close> for w :: \<open>'a::len word\<close>
+  using sdiv_smod_id [of 1 w] by auto
+
+lemma minus_one_sdiv_word_eq [simp]:
+  \<open>- 1 sdiv w = - (1 sdiv w)\<close> for w :: \<open>'a::len word\<close>
+  apply (auto simp add: sdiv_word_def signed_divide_int_def)
+  apply transfer
+  apply simp
+  done
+
+lemma minus_one_smod_word_eq [simp]:
+  \<open>- 1 smod w = - (1 smod w)\<close> for w :: \<open>'a::len word\<close>
+  using sdiv_smod_id [of \<open>- 1\<close> w] by auto
+
+lemma smod_word_alt_def:
+  "(a :: ('a::len) word) smod b = a - (a sdiv b) * b"
+  apply (cases \<open>a \<noteq> - (2 ^ (LENGTH('a) - 1)) \<or> b \<noteq> - 1\<close>)
+   apply (clarsimp simp: smod_word_def sdiv_word_def signed_modulo_int_def
+     simp flip: wi_hom_sub wi_hom_mult)
+  apply (clarsimp simp: smod_word_def signed_modulo_int_def)
+  done
+
+lemmas sdiv_word_numeral_numeral [simp] =
+  sdiv_word_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sdiv_word_minus_numeral_numeral [simp] =
+  sdiv_word_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sdiv_word_numeral_minus_numeral [simp] =
+  sdiv_word_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas sdiv_word_minus_numeral_minus_numeral [simp] =
+  sdiv_word_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+
+lemmas smod_word_numeral_numeral [simp] =
+  smod_word_def [of \<open>numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas smod_word_minus_numeral_numeral [simp] =
+  smod_word_def [of \<open>- numeral a\<close> \<open>numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas smod_word_numeral_minus_numeral [simp] =
+  smod_word_def [of \<open>numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+lemmas smod_word_minus_numeral_minus_numeral [simp] =
+  smod_word_def [of \<open>- numeral a\<close> \<open>- numeral b\<close>, simplified sint_sbintrunc sint_sbintrunc_neg]
+  for a b
+
 lemmas word_sdiv_0 = word_sdiv_div0
 
 lemma sdiv_word_min:
     "- (2 ^ (size a - 1)) \<le> sint (a :: ('a::len) word) sdiv sint (b :: ('a::len) word)"
   using sdiv_int_range [where a="sint a" and b="sint b"]
   apply auto
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply transfer
   apply simp
   apply (rule order_trans)
    defer
    apply assumption
   apply simp
   apply (metis abs_le_iff add.inverse_inverse le_cases le_minus_iff not_le signed_take_bit_int_eq_self_iff signed_take_bit_minus)
   done
 
 lemma sdiv_word_max:
   \<open>sint a sdiv sint b \<le> 2 ^ (size a - Suc 0)\<close>
   for a b :: \<open>'a::len word\<close>
 proof (cases \<open>sint a = 0 \<or> sint b = 0 \<or> sgn (sint a) \<noteq> sgn (sint b)\<close>)
   case True then show ?thesis
     apply (auto simp add: sgn_if not_less signed_divide_int_def split: if_splits)
      apply (smt (z3) pos_imp_zdiv_neg_iff zero_le_power)
     apply (smt (z3) not_exp_less_eq_0_int pos_imp_zdiv_neg_iff)
     done
 next
   case False
   then have \<open>\<bar>sint a\<bar> div \<bar>sint b\<bar> \<le> \<bar>sint a\<bar>\<close>
     by (subst nat_le_eq_zle [symmetric]) (simp_all add: div_abs_eq_div_nat)
   also have \<open>\<bar>sint a\<bar> \<le> 2 ^ (size a - Suc 0)\<close>
     using sint_range_size [of a] by auto
   finally show ?thesis
     using False by (simp add: signed_divide_int_def)
 qed
 
 lemmas word_sdiv_numerals_lhs = sdiv_word_def[where v="numeral x" for x]
     sdiv_word_def[where v=0] sdiv_word_def[where v=1]
 
 lemmas word_sdiv_numerals = word_sdiv_numerals_lhs[where w="numeral y" for y]
     word_sdiv_numerals_lhs[where w=0] word_sdiv_numerals_lhs[where w=1]
 
-lemma smod_word_mod_0 [simp]:
+lemma smod_word_mod_0:
   "x smod (0 :: ('a::len) word) = x"
-  by (clarsimp simp: smod_word_def)
+  by (fact smod_word_zero)
 
 lemma smod_word_0_mod [simp]:
   "0 smod (x :: ('a::len) word) = 0"
   by (clarsimp simp: smod_word_def)
 
 lemma smod_word_max:
   "sint (a::'a word) smod sint (b::'a word) < 2 ^ (LENGTH('a::len) - Suc 0)"
   apply (cases \<open>sint b = 0\<close>)
    apply (simp_all add: sint_less)
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   using smod_int_range [where a="sint a" and b="sint b"]
   apply auto
   apply (rule less_le_trans)
    apply assumption
   apply (auto simp add: abs_le_iff)
    apply (metis diff_Suc_1 le_cases linorder_not_le sint_lt)
   apply (metis add.inverse_inverse diff_Suc_1 linorder_not_less neg_less_iff_less sint_ge)
   done
 
 lemma smod_word_min:
   "- (2 ^ (LENGTH('a::len) - Suc 0)) \<le> sint (a::'a word) smod sint (b::'a word)"
   apply (cases \<open>LENGTH('a)\<close>)
    apply simp_all
   apply (cases \<open>sint b = 0\<close>)
    apply simp_all
    apply (metis diff_Suc_1 sint_ge)
   using smod_int_range [where a="sint a" and b="sint b"]
   apply auto
   apply (rule order_trans)
    defer
    apply assumption
   apply (auto simp add: algebra_simps abs_le_iff)
    apply (metis abs_zero add.left_neutral add_mono_thms_linordered_semiring(1) diff_Suc_1 le_cases linorder_not_less sint_lt zabs_less_one_iff)
   apply (metis abs_zero add.inverse_inverse add.left_neutral add_mono_thms_linordered_semiring(1) diff_Suc_1 le_cases le_minus_iff linorder_not_less sint_ge zabs_less_one_iff)
   done
 
-lemma smod_word_alt_def:
-  "(a :: ('a::len) word) smod b = a - (a sdiv b) * b"
-  apply (cases \<open>a \<noteq> - (2 ^ (LENGTH('a) - 1)) \<or> b \<noteq> - 1\<close>)
-   apply (clarsimp simp: smod_word_def sdiv_word_def signed_modulo_int_def
-     simp flip: wi_hom_sub wi_hom_mult)
-  apply (clarsimp simp: smod_word_def signed_modulo_int_def)
-  done
-
 lemmas word_smod_numerals_lhs = smod_word_def[where v="numeral x" for x]
     smod_word_def[where v=0] smod_word_def[where v=1]
 
 lemmas word_smod_numerals = word_smod_numerals_lhs[where w="numeral y" for y]
     word_smod_numerals_lhs[where w=0] word_smod_numerals_lhs[where w=1]
 
 end
\ No newline at end of file
diff --git a/thys/Word_Lib/Singleton_Bit_Shifts.thy b/thys/Word_Lib/Singleton_Bit_Shifts.thy
--- a/thys/Word_Lib/Singleton_Bit_Shifts.thy
+++ b/thys/Word_Lib/Singleton_Bit_Shifts.thy
@@ -1,138 +1,148 @@
 theory Singleton_Bit_Shifts
-  imports "HOL-Library.Word"
+  imports
+    "HOL-Library.Word"
+    Bit_Shifts_Infix_Syntax
 begin
 
 definition shiftl1 :: \<open>'a::len word \<Rightarrow> 'a word\<close>
   where \<open>shiftl1 = push_bit 1\<close>
 
 lemma bit_shiftl1_iff [bit_simps]:
   \<open>bit (shiftl1 w) n \<longleftrightarrow> 0 < n \<and> n < LENGTH('a) \<and> bit w (n - 1)\<close>
   for w :: \<open>'a::len word\<close>
   by (simp only: shiftl1_def bit_push_bit_iff) auto
 
 definition shiftr1 :: \<open>'a::len word \<Rightarrow> 'a word\<close>
   where \<open>shiftr1 = drop_bit 1\<close>
 
 lemma bit_shiftr1_iff [bit_simps]:
   \<open>bit (shiftr1 w) n \<longleftrightarrow> bit w (Suc n)\<close>
   for w :: \<open>'a::len word\<close>
   by (simp add: shiftr1_def bit_drop_bit_eq)
 
 definition sshiftr1 :: \<open>'a::len word \<Rightarrow> 'a word\<close>
   where \<open>sshiftr1 \<equiv> signed_drop_bit 1\<close>
 
 lemma bit_sshiftr1_iff [bit_simps]:
   \<open>bit (sshiftr1 w) n \<longleftrightarrow> bit w (if n = LENGTH('a) - 1 then LENGTH('a) - 1 else Suc n)\<close>
   for w :: \<open>'a::len word\<close>
   by (auto simp add: sshiftr1_def bit_signed_drop_bit_iff)
 
 lemma shiftr1_1: "shiftr1 (1::'a::len word) = 0"
   by (simp add: shiftr1_def)
 
 lemma sshiftr1_eq:
   \<open>sshiftr1 w = word_of_int (sint w div 2)\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps min_def simp flip: bit_Suc elim: le_SucE)
 
 lemma shiftl1_eq:
   \<open>shiftl1 w = word_of_int (2 * uint w)\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma shiftr1_eq:
   \<open>shiftr1 w = word_of_int (uint w div 2)\<close>
   by (rule bit_word_eqI) (simp add: bit_simps flip: bit_Suc)
 
 lemma shiftl1_rev:
   "shiftl1 w = word_reverse (shiftr1 (word_reverse w))"
   by (rule bit_word_eqI) (auto simp add: bit_simps Suc_diff_Suc simp flip: bit_Suc)
 
 lemma shiftl1_p:
   "shiftl1 w = w + w"
   for w :: "'a::len word"
   by (simp add: shiftl1_def)
 
 lemma shiftr1_bintr:
   "(shiftr1 (numeral w) :: 'a::len word) =
     word_of_int (take_bit LENGTH('a) (numeral w) div 2)"
   by (rule bit_word_eqI) (simp add: bit_simps bit_numeral_iff [where ?'a = int] flip: bit_Suc)
 
 lemma sshiftr1_sbintr:
   "(sshiftr1 (numeral w) :: 'a::len word) =
     word_of_int (signed_take_bit (LENGTH('a) - 1) (numeral w) div 2)"
   apply (cases \<open>LENGTH('a)\<close>)
   apply simp_all
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps min_def simp flip: bit_Suc elim: le_SucE)
   done
 
 lemma shiftl1_wi:
   "shiftl1 (word_of_int w) = word_of_int (2 * w)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma shiftl1_numeral:
   "shiftl1 (numeral w) = numeral (Num.Bit0 w)"
   unfolding word_numeral_alt shiftl1_wi by simp
 
 lemma shiftl1_neg_numeral:
   "shiftl1 (- numeral w) = - numeral (Num.Bit0 w)"
   unfolding word_neg_numeral_alt shiftl1_wi by simp
 
 lemma shiftl1_0:
   "shiftl1 0 = 0"
   by (simp add: shiftl1_def)
 
 lemma shiftl1_def_u:
   "shiftl1 w = word_of_int (2 * uint w)"
   by (fact shiftl1_eq)
 
 lemma shiftl1_def_s:
   "shiftl1 w = word_of_int (2 * sint w)"
   by (simp add: shiftl1_def)
 
 lemma shiftr1_0:
   "shiftr1 0 = 0"
   by (simp add: shiftr1_def)
 
 lemma sshiftr1_0:
   "sshiftr1 0 = 0"
   by (simp add: sshiftr1_def)
 
 lemma sshiftr1_n1:
   "sshiftr1 (- 1) = - 1"
   by (simp add: sshiftr1_def)
 
 lemma uint_shiftr1:
   "uint (shiftr1 w) = uint w div 2"
   by (rule bit_eqI) (simp add: bit_simps flip: bit_Suc)
 
 lemma shiftr1_div_2:
   "uint (shiftr1 w) = uint w div 2"
   by (fact uint_shiftr1)
 
 lemma sshiftr1_div_2:
   "sint (sshiftr1 w) = sint w div 2"
   by (rule bit_eqI) (auto simp add: bit_simps ac_simps min_def simp flip: bit_Suc elim: le_SucE)
 
 lemma nth_shiftl1:
   "bit (shiftl1 w) n \<longleftrightarrow> n < size w \<and> n > 0 \<and> bit w (n - 1)"
   by (auto simp add: word_size bit_simps)
 
 lemma nth_shiftr1:
   "bit (shiftr1 w) n = bit w (Suc n)"
   by (fact bit_shiftr1_iff)
 
 lemma nth_sshiftr1: "bit (sshiftr1 w) n = (if n = size w - 1 then bit w n else bit w (Suc n))"
   by (auto simp add: word_size bit_simps)
 
 lemma shiftl_power:
   "(shiftl1 ^^ x) (y::'a::len word) = 2 ^ x * y"
   by (induction x) (simp_all add: shiftl1_def)
 
 lemma le_shiftr1:
   \<open>shiftr1 u \<le> shiftr1 v\<close> if \<open>u \<le> v\<close>
   using that by (simp add: word_le_nat_alt unat_div div_le_mono shiftr1_def drop_bit_Suc)
 
 lemma le_shiftr1':
   "\<lbrakk> shiftr1 u \<le> shiftr1 v ; shiftr1 u \<noteq> shiftr1 v \<rbrakk> \<Longrightarrow> u \<le> v"
   by (meson dual_order.antisym le_cases le_shiftr1)
 
-end
\ No newline at end of file
+lemma sshiftr_eq_funpow_sshiftr1:
+  \<open>w >>> n = (sshiftr1 ^^ n) w\<close>
+  apply (rule sym)
+  apply (simp add: sshiftr1_def sshiftr_def)
+  apply (induction n)
+   apply simp_all
+  done
+
+end
diff --git a/thys/Word_Lib/Word_32.thy b/thys/Word_Lib/Word_32.thy
--- a/thys/Word_Lib/Word_32.thy
+++ b/thys/Word_Lib/Word_32.thy
@@ -1,345 +1,345 @@
 (*
  * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section "Words of Length 32"
 
 theory Word_32
   imports
     Word_Lemmas
     Word_Syntax
     Word_Names
     Rsplit
     More_Word_Operations
     Bitwise
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 type_synonym word32 = "32 word"
 lemma len32: "len_of (x :: 32 itself) = 32" by simp
 
 type_synonym sword32 = "32 sword"
 
 type_synonym machine_word_len = 32
 type_synonym machine_word = "machine_word_len word"
 
 definition word_bits :: nat
 where
   "word_bits = LENGTH(machine_word_len)"
 
 text \<open>The following two are numerals so they can be used as nats and words.\<close>
 definition word_size_bits :: "'a :: numeral"
 where
   "word_size_bits = 2"
 
 definition word_size :: "'a :: numeral"
 where
   "word_size = 4"
 
 lemma word_bits_conv[code]:
   "word_bits = 32"
   unfolding word_bits_def by simp
 
 lemma word_size_word_size_bits:
   "(word_size::nat) = 2 ^ word_size_bits"
   unfolding word_size_def word_size_bits_def by simp
 
 lemma word_bits_word_size_conv:
   "word_bits = word_size * 8"
   unfolding word_bits_def word_size_def by simp
 
 lemma ucast_8_32_inj:
   "inj (ucast ::  8 word \<Rightarrow> 32 word)"
   by (rule down_ucast_inj) (clarsimp simp: is_down_def target_size source_size)
 
 lemma upto_2_helper:
   "{0..<2 :: 32 word} = {0, 1}"
   by (safe; simp) unat_arith
 
 lemmas upper_bits_unset_is_l2p_32 = upper_bits_unset_is_l2p [where 'a=32, folded word_bits_def]
 lemmas le_2p_upper_bits_32 = le_2p_upper_bits [where 'a=32, folded word_bits_def]
 lemmas le2p_bits_unset_32 = le2p_bits_unset[where 'a=32, folded word_bits_def]
 
 lemma word_bits_len_of:
   "len_of TYPE (32) = word_bits"
   by (simp add: word_bits_conv)
 
 lemmas unat_power_lower32' = unat_power_lower[where 'a=32]
 lemmas unat_power_lower32 [simp] = unat_power_lower32'[unfolded word_bits_len_of]
 
 lemmas word32_less_sub_le' = word_less_sub_le[where 'a = 32]
 lemmas word32_less_sub_le[simp] = word32_less_sub_le' [folded word_bits_def]
 
 lemma word_bits_size:
   "size (w::word32) = word_bits"
   by (simp add: word_bits_def word_size)
 
 lemmas word32_power_less_1' = word_power_less_1[where 'a = 32]
 lemmas word32_power_less_1[simp] = word32_power_less_1'[folded word_bits_def]
 
 lemma of_nat32_0:
   "\<lbrakk>of_nat n = (0::word32); n < 2 ^ word_bits\<rbrakk> \<Longrightarrow> n = 0"
   by (erule of_nat_0, simp add: word_bits_def)
 
 lemma unat_mask_2_less_4:
   "unat (p && mask 2 :: word32) < 4"
-  by (rule unat_less_helper) (simp flip: take_bit_eq_mask add: take_bit_eq_mod word_mod_less_divisor)
+  by (rule unat_less_helper) (simp only: take_bit_eq_mod word_mod_less_divisor flip: take_bit_eq_mask, simp add: word_mod_less_divisor)
 
 lemmas unat_of_nat32' = unat_of_nat_eq[where 'a=32]
 lemmas unat_of_nat32 = unat_of_nat32'[unfolded word_bits_len_of]
 
 lemmas word_power_nonzero_32 = word_power_nonzero [where 'a=32, folded word_bits_def]
 
 lemmas unat_mult_simple = iffD1 [OF unat_mult_lem [where 'a = 32, unfolded word_bits_len_of]]
 
 lemmas div_power_helper_32 = div_power_helper [where 'a=32, folded word_bits_def]
 
 lemma n_less_word_bits:
   "(n < word_bits) = (n < 32)"
   by (simp add: word_bits_def)
 
 lemmas of_nat_less_pow_32 = of_nat_power [where 'a=32, folded word_bits_def]
 
 lemma lt_word_bits_lt_pow:
   "sz < word_bits \<Longrightarrow> sz < 2 ^ word_bits"
   by (simp add: word_bits_conv)
 
 lemma unat_less_word_bits:
   fixes y :: word32
   shows "x < unat y \<Longrightarrow> x < 2 ^ word_bits"
   unfolding word_bits_def
   by (rule order_less_trans [OF _ unat_lt2p])
 
 lemmas unat_mask_word32' = unat_mask[where 'a=32]
 lemmas unat_mask_word32 = unat_mask_word32'[folded word_bits_def]
 
 lemma unat_less_2p_word_bits:
   "unat (x :: 32 word) < 2 ^ word_bits"
   apply (simp only: word_bits_def)
   apply (rule unat_lt2p)
   done
 
 lemma Suc_unat_mask_div:
   "Suc (unat (mask sz div word_size::word32)) = 2 ^ (min sz word_bits - 2)"
 proof (cases \<open>sz \<ge> 2\<close>)
   case False
   then have \<open>sz \<in> {0, 1}\<close>
     by auto
   then show ?thesis by (auto simp add: unat_div word_size_def)
 next
   case True
   moreover define n where \<open>n = sz - 2\<close>
   ultimately have \<open>sz = n + 2\<close>
     by simp
   moreover have \<open>4 * 2 ^ n = 2 ^ n * (4::nat)\<close>
     by (simp add: ac_simps)
   then have \<open>4 * 2 ^ n - Suc 0 = (2 ^ n - 1) * 4 + 3\<close>
     by (simp add: mult_eq_if)
   ultimately show ?thesis
     by (simp add: unat_div unat_mask word_size_def word_bits_def min_def)
 qed
 
 lemmas word32_minus_one_le' = word_minus_one_le[where 'a=32]
 lemmas word32_minus_one_le = word32_minus_one_le'[simplified]
 
 lemma ucast_not_helper:
   fixes a::"8 word"
   assumes a: "a \<noteq> 0xFF"
   shows "ucast a \<noteq> (0xFF::word32)"
 proof
   assume "ucast a = (0xFF::word32)"
   also
   have "(0xFF::word32) = ucast (0xFF::8 word)" by simp
   finally
   show False using a
     apply -
     apply (drule up_ucast_inj, simp)
     apply simp
     done
 qed
 
 lemma less_4_cases:
   "(x::word32) < 4 \<Longrightarrow> x=0 \<or> x=1 \<or> x=2 \<or> x=3"
   apply clarsimp
   apply (drule word_less_cases, erule disjE, simp, simp)+
   done
 
 lemma unat_ucast_8_32:
   fixes x :: "8 word"
   shows "unat (ucast x :: word32) = unat x"
   by transfer simp
 
 lemma if_then_1_else_0:
   "((if P then 1 else 0) = (0 :: word32)) = (\<not> P)"
   by simp
 
 lemma if_then_0_else_1:
   "((if P then 0 else 1) = (0 :: word32)) = (P)"
   by simp
 
 lemmas if_then_simps = if_then_0_else_1 if_then_1_else_0
 
 lemma ucast_le_ucast_8_32:
   "(ucast x \<le> (ucast y :: word32)) = (x \<le> (y :: 8 word))"
   by (simp add: ucast_le_ucast)
 
 lemma in_16_range:
   "0 \<in> S \<Longrightarrow> r \<in> (\<lambda>x. r + x * (16 :: word32)) ` S"
   "n - 1 \<in> S \<Longrightarrow> (r + (16 * n - 16)) \<in> (\<lambda>x :: word32. r + x * 16) ` S"
   by (clarsimp simp: image_def elim!: bexI[rotated])+
 
 lemma eq_2_32_0:
   "(2 ^ 32 :: word32) = 0"
   by simp
 
 lemma x_less_2_0_1:
   fixes x :: word32 shows
   "x < 2 \<Longrightarrow> x = 0 \<or> x = 1"
   by (rule x_less_2_0_1') auto
 
 lemmas mask_32_max_word  = max_word_mask [symmetric, where 'a=32, simplified]
 
 lemma of_nat32_n_less_equal_power_2:
  "n < 32 \<Longrightarrow> ((of_nat n)::32 word) < 2 ^ n"
   by (rule of_nat_n_less_equal_power_2, clarsimp simp: word_size)
 
 lemma word_rsplit_0:
   "word_rsplit (0 :: word32) = [0, 0, 0, 0 :: 8 word]"
   by (simp add: word_rsplit_def bin_rsplit_def)
 
 lemma unat_ucast_10_32 :
   fixes x :: "10 word"
   shows "unat (ucast x :: word32) = unat x"
   by transfer simp
 
 lemma bool_mask [simp]:
   fixes x :: word32
   shows "(0 < x && 1) = (x && 1 = 1)"
   by (rule bool_mask') auto
 
 lemma word32_bounds:
   "- (2 ^ (size (x :: word32) - 1)) = (-2147483648 :: int)"
   "((2 ^ (size (x :: word32) - 1)) - 1) = (2147483647 :: int)"
   "- (2 ^ (size (y :: 32 signed word) - 1)) = (-2147483648 :: int)"
   "((2 ^ (size (y :: 32 signed word) - 1)) - 1) = (2147483647 :: int)"
   by (simp_all add: word_size)
 
 lemma word_ge_min:"sint (x::32 word) \<ge> -2147483648"
   by (metis sint_ge word32_bounds(1) word_size)
 
 lemmas signed_arith_ineq_checks_to_eq_word32'
     = signed_arith_ineq_checks_to_eq[where 'a=32]
       signed_arith_ineq_checks_to_eq[where 'a="32 signed"]
 
 lemmas signed_arith_ineq_checks_to_eq_word32
     = signed_arith_ineq_checks_to_eq_word32' [unfolded word32_bounds]
 
 lemmas signed_mult_eq_checks32_to_64'
     = signed_mult_eq_checks_double_size[where 'a=32 and 'b=64]
       signed_mult_eq_checks_double_size[where 'a="32 signed" and 'b=64]
 
 lemmas signed_mult_eq_checks32_to_64 = signed_mult_eq_checks32_to_64'[simplified]
 
 lemmas sdiv_word32_max' = sdiv_word_max [where 'a=32] sdiv_word_max [where 'a="32 signed"]
 lemmas sdiv_word32_max = sdiv_word32_max'[simplified word_size, simplified]
 
 lemmas sdiv_word32_min' = sdiv_word_min [where 'a=32] sdiv_word_min [where 'a="32 signed"]
 lemmas sdiv_word32_min = sdiv_word32_min' [simplified word_size, simplified]
 
 lemmas sint32_of_int_eq' = sint_of_int_eq [where 'a=32]
 lemmas sint32_of_int_eq = sint32_of_int_eq' [simplified]
 
 lemma ucast_of_nats [simp]:
   "(ucast (of_nat x :: word32) :: sword32) = (of_nat x)"
   "(ucast (of_nat x :: word32) :: 16 sword) = (of_nat x)"
   "(ucast (of_nat x :: word32) :: 8 sword) = (of_nat x)"
   "(ucast (of_nat x :: 16 word) :: 16 sword) = (of_nat x)"
   "(ucast (of_nat x :: 16 word) :: 8 sword) = (of_nat x)"
   "(ucast (of_nat x :: 8 word) :: 8 sword) = (of_nat x)"
   by (simp_all add: of_nat_take_bit take_bit_word_eq_self unsigned_of_nat)
 
 lemmas signed_shift_guard_simpler_32'
     = power_strict_increasing_iff[where b="2 :: nat" and y=31]
 lemmas signed_shift_guard_simpler_32 = signed_shift_guard_simpler_32'[simplified]
 
 lemma word32_31_less:
   "31 < len_of TYPE (32 signed)" "31 > (0 :: nat)"
   "31 < len_of TYPE (32)" "31 > (0 :: nat)"
   by auto
 
 lemmas signed_shift_guard_to_word_32
     = signed_shift_guard_to_word[OF word32_31_less(1-2)]
     signed_shift_guard_to_word[OF word32_31_less(3-4)]
 
 lemma le_step_down_word_3:
   fixes x :: "32 word"
   shows "\<lbrakk>x \<le>  y; x \<noteq> y; y < 2 ^ 32 - 1\<rbrakk> \<Longrightarrow> x \<le> y - 1"
   by (rule le_step_down_word_2, assumption+)
 
 lemma shiftr_1:
   "(x::word32) >> 1 = 0 \<Longrightarrow> x < 2"
   by transfer (simp add: take_bit_drop_bit drop_bit_Suc)
 
 lemma has_zero_byte:
   "~~ (((((v::word32) && 0x7f7f7f7f) + 0x7f7f7f7f) || v) || 0x7f7f7f7f) \<noteq> 0
     \<Longrightarrow> v && 0xff000000 = 0 \<or> v && 0xff0000 = 0 \<or> v && 0xff00 = 0 \<or> v && 0xff = 0"
   by word_bitwise auto
 
 lemma mask_step_down_32:
   \<open>\<exists>x. mask x = b\<close> if \<open>b && 1 = 1\<close>
     and \<open>\<exists>x. x < 32 \<and> mask x = b >> 1\<close> for b :: \<open>32word\<close>
 proof -
   from \<open>b && 1 = 1\<close> have \<open>odd b\<close>
     by (auto simp add: mod_2_eq_odd and_one_eq)
   then have \<open>b mod 2 = 1\<close>
     using odd_iff_mod_2_eq_one by blast
   from \<open>\<exists>x. x < 32 \<and> mask x = b >> 1\<close> obtain x where \<open>x < 32\<close> \<open>mask x = b >> 1\<close> by blast
   then have \<open>mask x = b div 2\<close>
     using shiftr1_is_div_2 [of b] by simp
   with \<open>b mod 2 = 1\<close> have \<open>2 * mask x + 1 = 2 * (b div 2) + b mod 2\<close>
     by (simp only:)
   also have \<open>\<dots> = b\<close>
     by (simp add: mult_div_mod_eq)
   finally have \<open>2 * mask x + 1 = b\<close> .
   moreover have \<open>mask (Suc x) = 2 * mask x + (1 :: 'a::len word)\<close>
     by (simp add: mask_Suc_rec)
   ultimately show ?thesis
     by auto
 qed
 
 lemma unat_of_int_32:
   "\<lbrakk>i \<ge> 0; i \<le>2 ^ 31\<rbrakk> \<Longrightarrow> (unat ((of_int i)::sword32)) = nat i"
   by (simp add: unsigned_of_int nat_take_bit_eq take_bit_nat_eq_self)
 
 lemmas word_ctz_not_minus_1_32 = word_ctz_not_minus_1[where 'a=32, simplified]
 
 (* Helper for packing then unpacking a 64-bit variable. *)
 lemma cast_chunk_assemble_id_64[simp]:
   "(((ucast ((ucast (x::64 word))::32 word))::64 word) || (((ucast ((ucast (x >> 32))::32 word))::64 word) << 32)) = x"
   by (simp add:cast_chunk_assemble_id)
 
 (* Another variant of packing and unpacking a 64-bit variable. *)
 lemma cast_chunk_assemble_id_64'[simp]:
   "(((ucast ((scast (x::64 word))::32 word))::64 word) || (((ucast ((scast (x >> 32))::32 word))::64 word) << 32)) = x"
   by (simp add:cast_chunk_scast_assemble_id)
 
 (* Specialisations of down_cast_same for adding to local simpsets. *)
 lemma cast_down_u64: "(scast::64 word \<Rightarrow> 32 word) = (ucast::64 word \<Rightarrow> 32 word)"
   by (subst down_cast_same[symmetric]; simp add:is_down)+
 
 lemma cast_down_s64: "(scast::64 sword \<Rightarrow> 32 word) = (ucast::64 sword \<Rightarrow> 32 word)"
   by (subst down_cast_same[symmetric]; simp add:is_down)
 
 lemma word32_and_max_simp:
   \<open>x AND 0xFFFFFFFF = x\<close> for x :: \<open>32 word\<close>
   using word_and_full_mask_simp [of x]
   by (simp add: numeral_eq_Suc mask_Suc_exp)
 
 end
 
 end
diff --git a/thys/Word_Lib/Word_64.thy b/thys/Word_Lib/Word_64.thy
--- a/thys/Word_Lib/Word_64.thy
+++ b/thys/Word_Lib/Word_64.thy
@@ -1,309 +1,309 @@
 (*
  * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section "Words of Length 64"
 
 theory Word_64
   imports
     Word_Lemmas
     Word_Names
     Word_Syntax
     Rsplit
     More_Word_Operations
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 lemma len64: "len_of (x :: 64 itself) = 64" by simp
 
 type_synonym machine_word_len = 64
 type_synonym machine_word = "machine_word_len word"
 
 definition word_bits :: nat
 where
   "word_bits = LENGTH(machine_word_len)"
 
 text \<open>The following two are numerals so they can be used as nats and words.\<close>
 definition word_size_bits :: "'a :: numeral"
 where
   "word_size_bits = 3"
 
 definition word_size :: "'a :: numeral"
 where
   "word_size = 8"
 
 lemma word_bits_conv[code]:
   "word_bits = 64"
   unfolding word_bits_def by simp
 
 lemma word_size_word_size_bits:
   "(word_size::nat) = 2 ^ word_size_bits"
   unfolding word_size_def word_size_bits_def by simp
 
 lemma word_bits_word_size_conv:
   "word_bits = word_size * 8"
   unfolding word_bits_def word_size_def by simp
 
 lemma ucast_8_64_inj:
   "inj (ucast ::  8 word \<Rightarrow> 64 word)"
   by (rule down_ucast_inj) (clarsimp simp: is_down_def target_size source_size)
 
 lemma upto_2_helper:
   "{0..<2 :: 64 word} = {0, 1}"
   by (safe; simp) unat_arith
 
 lemmas upper_bits_unset_is_l2p_64 = upper_bits_unset_is_l2p [where 'a=64, folded word_bits_def]
 lemmas le_2p_upper_bits_64 = le_2p_upper_bits [where 'a=64, folded word_bits_def]
 lemmas le2p_bits_unset_64 = le2p_bits_unset[where 'a=64, folded word_bits_def]
 
 lemma word_bits_len_of:
   "len_of TYPE (64) = word_bits"
   by (simp add: word_bits_conv)
 
 lemmas unat_power_lower64' = unat_power_lower[where 'a=64]
 lemmas unat_power_lower64 [simp] = unat_power_lower64'[unfolded word_bits_len_of]
 
 lemmas word64_less_sub_le' = word_less_sub_le[where 'a = 64]
 lemmas word64_less_sub_le[simp] = word64_less_sub_le' [folded word_bits_def]
 
 lemma word_bits_size:
   "size (w::word64) = word_bits"
   by (simp add: word_bits_def word_size)
 
 lemmas word64_power_less_1' = word_power_less_1[where 'a = 64]
 lemmas word64_power_less_1[simp] = word64_power_less_1'[folded word_bits_def]
 
 lemma of_nat64_0:
   "\<lbrakk>of_nat n = (0::word64); n < 2 ^ word_bits\<rbrakk> \<Longrightarrow> n = 0"
   by (erule of_nat_0, simp add: word_bits_def)
 
 lemma unat_mask_2_less_4:
   "unat (p && mask 2 :: word64) < 4"
-  by (rule unat_less_helper) (simp flip: take_bit_eq_mask add: take_bit_eq_mod word_mod_less_divisor)
+  by (rule unat_less_helper) (simp only: take_bit_eq_mod word_mod_less_divisor flip: take_bit_eq_mask, simp add: word_mod_less_divisor)
 
 lemmas unat_of_nat64' = unat_of_nat_eq[where 'a=64]
 lemmas unat_of_nat64 = unat_of_nat64'[unfolded word_bits_len_of]
 
 lemmas word_power_nonzero_64 = word_power_nonzero [where 'a=64, folded word_bits_def]
 
 lemmas unat_mult_simple = iffD1 [OF unat_mult_lem [where 'a = 64, unfolded word_bits_len_of]]
 
 lemmas div_power_helper_64 = div_power_helper [where 'a=64, folded word_bits_def]
 
 lemma n_less_word_bits:
   "(n < word_bits) = (n < 64)"
   by (simp add: word_bits_def)
 
 lemmas of_nat_less_pow_64 = of_nat_power [where 'a=64, folded word_bits_def]
 
 lemma lt_word_bits_lt_pow:
   "sz < word_bits \<Longrightarrow> sz < 2 ^ word_bits"
   by (simp add: word_bits_conv)
 
 lemma unat_less_word_bits:
   fixes y :: word64
   shows "x < unat y \<Longrightarrow> x < 2 ^ word_bits"
   unfolding word_bits_def
   by (rule order_less_trans [OF _ unat_lt2p])
 
 lemmas unat_mask_word64' = unat_mask[where 'a=64]
 lemmas unat_mask_word64 = unat_mask_word64'[folded word_bits_def]
 
 lemma unat_less_2p_word_bits:
   "unat (x :: 64 word) < 2 ^ word_bits"
   apply (simp only: word_bits_def)
   apply (rule unat_lt2p)
   done
 
 lemma Suc_unat_mask_div:
   "Suc (unat (mask sz div word_size::word64)) = 2 ^ (min sz word_bits - 3)"
 proof (cases \<open>sz \<ge> 3\<close>)
   case False
   then have \<open>sz \<in> {0, 1, 2}\<close>
     by auto
   then show ?thesis by (auto simp add: unat_div word_size_def unat_mask)
 next
   case True
   moreover define n where \<open>n = sz - 3\<close>
   ultimately have \<open>sz = n + 3\<close>
     by simp
   moreover have \<open>2 ^ n * 8 - Suc 0 = (2 ^ n - 1) * 8 + 7\<close>
     by (simp add: mult_eq_if)
   ultimately show ?thesis
     by (simp add: unat_div unat_mask word_size_def word_bits_def min_def power_add)
 qed
 
 lemmas word64_minus_one_le' = word_minus_one_le[where 'a=64]
 lemmas word64_minus_one_le = word64_minus_one_le'[simplified]
 
 lemma ucast_not_helper:
   fixes a::"8 word"
   assumes a: "a \<noteq> 0xFF"
   shows "ucast a \<noteq> (0xFF::word64)"
 proof
   assume "ucast a = (0xFF::word64)"
   also
   have "(0xFF::word64) = ucast (0xFF::8 word)" by simp
   finally
   show False using a
     apply -
     apply (drule up_ucast_inj, simp)
     apply simp
     done
 qed
 
 lemma less_4_cases:
   "(x::word64) < 4 \<Longrightarrow> x=0 \<or> x=1 \<or> x=2 \<or> x=3"
   apply clarsimp
   apply (drule word_less_cases, erule disjE, simp, simp)+
   done
 
 lemma if_then_1_else_0:
   "((if P then 1 else 0) = (0 :: word64)) = (\<not> P)"
   by simp
 
 lemma if_then_0_else_1:
   "((if P then 0 else 1) = (0 :: word64)) = (P)"
   by simp
 
 lemmas if_then_simps = if_then_0_else_1 if_then_1_else_0
 
 lemma ucast_le_ucast_8_64:
   "(ucast x \<le> (ucast y :: word64)) = (x \<le> (y :: 8 word))"
   by (simp add: ucast_le_ucast)
 
 lemma in_16_range:
   "0 \<in> S \<Longrightarrow> r \<in> (\<lambda>x. r + x * (16 :: word64)) ` S"
   "n - 1 \<in> S \<Longrightarrow> (r + (16 * n - 16)) \<in> (\<lambda>x :: word64. r + x * 16) ` S"
   by (clarsimp simp: image_def elim!: bexI[rotated])+
 
 lemma eq_2_64_0:
   "(2 ^ 64 :: word64) = 0"
   by simp
 
 lemma x_less_2_0_1:
   fixes x :: word64 shows
   "x < 2 \<Longrightarrow> x = 0 \<or> x = 1"
   by (rule x_less_2_0_1') auto
 
 lemmas mask_64_max_word  = max_word_mask [symmetric, where 'a=64, simplified]
 
 lemma of_nat64_n_less_equal_power_2:
  "n < 64 \<Longrightarrow> ((of_nat n)::64 word) < 2 ^ n"
   by (rule of_nat_n_less_equal_power_2, clarsimp simp: word_size)
 
 lemma word_rsplit_0:
   "word_rsplit (0 :: word64) = [0, 0, 0, 0, 0, 0, 0, 0 :: 8 word]"
   by (simp add: word_rsplit_def bin_rsplit_def)
 
 lemma unat_ucast_10_64 :
   fixes x :: "10 word"
   shows "unat (ucast x :: word64) = unat x"
   by transfer simp
 
 lemma bool_mask [simp]:
   fixes x :: word64
   shows "(0 < x && 1) = (x && 1 = 1)"
   by (rule bool_mask') auto
 
 lemma word64_bounds:
   "- (2 ^ (size (x :: word64) - 1)) = (-9223372036854775808 :: int)"
   "((2 ^ (size (x :: word64) - 1)) - 1) = (9223372036854775807 :: int)"
   "- (2 ^ (size (y :: 64 signed word) - 1)) = (-9223372036854775808 :: int)"
   "((2 ^ (size (y :: 64 signed word) - 1)) - 1) = (9223372036854775807 :: int)"
   by (simp_all add: word_size)
 
 lemma word_ge_min:"sint (x::64 word) \<ge> -9223372036854775808"
   by (metis sint_ge word64_bounds(1) word_size)
 
 lemmas signed_arith_ineq_checks_to_eq_word64'
     = signed_arith_ineq_checks_to_eq[where 'a=64]
       signed_arith_ineq_checks_to_eq[where 'a="64 signed"]
 
 lemmas signed_arith_ineq_checks_to_eq_word64
     = signed_arith_ineq_checks_to_eq_word64' [unfolded word64_bounds]
 
 lemmas signed_mult_eq_checks64_to_64'
     = signed_mult_eq_checks_double_size[where 'a=64 and 'b=64]
       signed_mult_eq_checks_double_size[where 'a="64 signed" and 'b=64]
 
 lemmas signed_mult_eq_checks64_to_64 = signed_mult_eq_checks64_to_64'[simplified]
 
 lemmas sdiv_word64_max' = sdiv_word_max [where 'a=64] sdiv_word_max [where 'a="64 signed"]
 lemmas sdiv_word64_max = sdiv_word64_max'[simplified word_size, simplified]
 
 lemmas sdiv_word64_min' = sdiv_word_min [where 'a=64] sdiv_word_min [where 'a="64 signed"]
 lemmas sdiv_word64_min = sdiv_word64_min' [simplified word_size, simplified]
 
 lemmas sint64_of_int_eq' = sint_of_int_eq [where 'a=64]
 lemmas sint64_of_int_eq = sint64_of_int_eq' [simplified]
 
 lemma ucast_of_nats [simp]:
   "(ucast (of_nat x :: word64) :: sword64) = (of_nat x)"
   "(ucast (of_nat x :: word64) :: 16 sword) = (of_nat x)"
   "(ucast (of_nat x :: word64) :: 8 sword) = (of_nat x)"
   by (simp_all add: of_nat_take_bit take_bit_word_eq_self unsigned_of_nat)
 
 lemmas signed_shift_guard_simpler_64'
     = power_strict_increasing_iff[where b="2 :: nat" and y=31]
 lemmas signed_shift_guard_simpler_64 = signed_shift_guard_simpler_64'[simplified]
 
 lemma word64_31_less:
   "31 < len_of TYPE (64 signed)" "31 > (0 :: nat)"
   "31 < len_of TYPE (64)" "31 > (0 :: nat)"
   by auto
 
 lemmas signed_shift_guard_to_word_64
     = signed_shift_guard_to_word[OF word64_31_less(1-2)]
     signed_shift_guard_to_word[OF word64_31_less(3-4)]
 
 lemma le_step_down_word_3:
   fixes x :: "64 word"
   shows "\<lbrakk>x \<le>  y; x \<noteq> y; y < 2 ^ 64 - 1\<rbrakk> \<Longrightarrow> x \<le> y - 1"
   by (rule le_step_down_word_2, assumption+)
 
 lemma shiftr_1:
   "(x::word64) >> 1 = 0 \<Longrightarrow> x < 2"
   by transfer (simp add: take_bit_drop_bit drop_bit_Suc)
 
 lemma mask_step_down_64:
   \<open>\<exists>x. mask x = b\<close> if \<open>b && 1 = 1\<close>
     and \<open>\<exists>x. x < 64 \<and> mask x = b >> 1\<close> for b :: \<open>64word\<close>
 proof -
   from \<open>b && 1 = 1\<close> have \<open>odd b\<close>
     by (auto simp add: mod_2_eq_odd and_one_eq)
   then have \<open>b mod 2 = 1\<close>
     using odd_iff_mod_2_eq_one by blast
   from \<open>\<exists>x. x < 64 \<and> mask x = b >> 1\<close> obtain x where \<open>x < 64\<close> \<open>mask x = b >> 1\<close> by blast
   then have \<open>mask x = b div 2\<close>
     using shiftr1_is_div_2 [of b] by simp
   with \<open>b mod 2 = 1\<close> have \<open>2 * mask x + 1 = 2 * (b div 2) + b mod 2\<close>
     by (simp only:)
   also have \<open>\<dots> = b\<close>
     by (simp add: mult_div_mod_eq)
   finally have \<open>2 * mask x + 1 = b\<close> .
   moreover have \<open>mask (Suc x) = 2 * mask x + (1 :: 'a::len word)\<close>
     by (simp add: mask_Suc_rec)
   ultimately show ?thesis
     by auto
 qed
 
 lemma unat_of_int_64:
   "\<lbrakk>i \<ge> 0; i \<le> 2 ^ 63\<rbrakk> \<Longrightarrow> (unat ((of_int i)::sword64)) = nat i"
   by (simp add: unsigned_of_int nat_take_bit_eq take_bit_nat_eq_self)
 
 lemmas word_ctz_not_minus_1_64 = word_ctz_not_minus_1[where 'a=64, simplified]
 
 lemma word64_and_max_simp:
   \<open>x AND 0xFFFFFFFFFFFFFFFF = x\<close> for x :: \<open>64 word\<close>
   using word_and_full_mask_simp [of x]
   by (simp add: numeral_eq_Suc mask_Suc_exp)
 
 end
 
 end
diff --git a/thys/Word_Lib/Word_EqI.thy b/thys/Word_Lib/Word_EqI.thy
--- a/thys/Word_Lib/Word_EqI.thy
+++ b/thys/Word_Lib/Word_EqI.thy
@@ -1,69 +1,72 @@
 (*
  * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section "Solving Word Equalities"
 
 theory Word_EqI
   imports
     More_Word
+    Aligned
     "HOL-Eisbach.Eisbach_Tools"
 begin
 
 text \<open>
   Some word equalities can be solved by considering the problem bitwise for all
   @{prop "n < LENGTH('a::len)"}, which is different to running @{text word_bitwise}
   and expanding into an explicit list of bits.
 \<close>
 
 named_theorems word_eqI_simps
 
 lemmas [word_eqI_simps] =
   word_ops_nth_size
   bit_mask_iff
   word_size
   word_or_zero
   neg_mask_test_bit
   nth_ucast
   nth_w2p bit_push_bit_iff
   bit_drop_bit_eq
   less_2p_is_upper_bits_unset
   le_mask_high_bits
   bang_eq
   neg_test_bit
   is_up
   is_down
+  is_aligned_nth
+  neg_mask_le_high_bits
 
 lemmas word_eqI_rule = word_eqI [rule_format]
 
 lemma test_bit_lenD:
   "bit x n \<Longrightarrow> n < LENGTH('a) \<and> bit x n" for x :: "'a :: len word"
   by (fastforce dest: test_bit_size simp: word_size)
 
 method word_eqI uses simp simp_del split split_del cong flip =
   ((* reduce conclusion to test_bit: *)
    rule word_eqI_rule,
    (* make sure we're in clarsimp normal form: *)
    (clarsimp simp: simp simp del: simp_del simp flip: flip split: split split del: split_del cong: cong)?,
    (* turn x < 2^n assumptions into mask equations: *)
    ((drule less_mask_eq)+)?,
    (* expand and distribute test_bit everywhere: *)
    (clarsimp simp: word_eqI_simps simp simp del: simp_del simp flip: flip
              split: split split del: split_del cong: cong)?,
    (* add any additional word size constraints to new indices: *)
    ((drule test_bit_lenD)+)?,
    (* try to make progress (can't use +, would loop): *)
    (clarsimp simp: word_eqI_simps simp simp del: simp_del simp flip: flip
              split: split split del: split_del cong: cong)?,
    (* helps sometimes, rarely: *)
    (simp add: simp test_bit_conj_lt del: simp_del flip: flip split: split split del: split_del cong: cong)?)
 
 method word_eqI_solve uses simp simp_del split split_del cong flip =
   solves \<open>word_eqI simp: simp simp_del: simp_del split: split split_del: split_del
                    cong: cong simp flip: flip;
           (fastforce dest: test_bit_size simp: word_eqI_simps simp flip: flip
                      simp: simp simp del: simp_del split: split split del: split_del cong: cong)?\<close>
 
 end
diff --git a/thys/Word_Lib/Word_Lemmas.thy b/thys/Word_Lib/Word_Lemmas.thy
--- a/thys/Word_Lib/Word_Lemmas.thy
+++ b/thys/Word_Lib/Word_Lemmas.thy
@@ -1,1940 +1,1961 @@
 (*
  * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
  *
  * SPDX-License-Identifier: BSD-2-Clause
  *)
 
 section "Lemmas with Generic Word Length"
 
 theory Word_Lemmas
   imports
     Type_Syntax
     Signed_Division_Word
     Signed_Words
     More_Word
     Most_significant_bit
     Enumeration_Word
     Aligned
     Bit_Shifts_Infix_Syntax
 begin
 
 context
   includes bit_operations_syntax
 begin
 
 lemma ucast_le_ucast_eq:
   fixes x y :: "'a::len word"
   assumes x: "x < 2 ^ n"
   assumes y: "y < 2 ^ n"
   assumes n: "n = LENGTH('b::len)"
   shows "(UCAST('a \<rightarrow> 'b) x \<le> UCAST('a \<rightarrow> 'b) y) = (x \<le> y)"
   apply (rule iffI)
    apply (cases "LENGTH('b) < LENGTH('a)")
     apply (subst less_mask_eq[OF x, symmetric])
     apply (subst less_mask_eq[OF y, symmetric])
     apply (unfold n)
     apply (subst ucast_ucast_mask[symmetric])+
     apply (simp add: ucast_le_ucast)+
   apply (erule ucast_mono_le[OF _ y[unfolded n]])
   done
 
 lemma ucast_zero_is_aligned:
   \<open>is_aligned w n\<close> if \<open>UCAST('a::len \<rightarrow> 'b::len) w = 0\<close> \<open>n \<le> LENGTH('b)\<close>
 proof (rule is_aligned_bitI)
   fix q
   assume \<open>q < n\<close>
   moreover have \<open>bit (UCAST('a::len \<rightarrow> 'b::len) w) q = bit 0 q\<close>
     using that by simp
   with \<open>q < n\<close> \<open>n \<le> LENGTH('b)\<close> show \<open>\<not> bit w q\<close>
     by (simp add: bit_simps)
 qed
 
 lemma unat_ucast_eq_unat_and_mask:
   "unat (UCAST('b::len \<rightarrow> 'a::len) w) = unat (w AND mask LENGTH('a))"
   apply (simp flip: take_bit_eq_mask)
   apply transfer
   apply (simp add: ac_simps)
   done
 
 lemma le_max_word_ucast_id:
   \<open>UCAST('b \<rightarrow> 'a) (UCAST('a \<rightarrow> 'b) x) = x\<close>
     if \<open>x \<le> UCAST('b::len \<rightarrow> 'a) (- 1)\<close>
     for x :: \<open>'a::len word\<close>
 proof -
   from that have a1: \<open>x \<le> word_of_int (uint (word_of_int (2 ^ LENGTH('b) - 1) :: 'b word))\<close>
-    by simp
+    by (simp add: of_int_mask_eq)
   have f2: "((\<exists>i ia. (0::int) \<le> i \<and> \<not> 0 \<le> i + - 1 * ia \<and> i mod ia \<noteq> i) \<or>
             \<not> (0::int) \<le> - 1 + 2 ^ LENGTH('b) \<or> (0::int) \<le> - 1 + 2 ^ LENGTH('b) + - 1 * 2 ^ LENGTH('b) \<or>
             (- (1::int) + 2 ^ LENGTH('b)) mod 2 ^ LENGTH('b) =
               - 1 + 2 ^ LENGTH('b)) = ((\<exists>i ia. (0::int) \<le> i \<and> \<not> 0 \<le> i + - 1 * ia \<and> i mod ia \<noteq> i) \<or>
             \<not> (1::int) \<le> 2 ^ LENGTH('b) \<or>
             2 ^ LENGTH('b) + - (1::int) * ((- 1 + 2 ^ LENGTH('b)) mod 2 ^ LENGTH('b)) = 1)"
     by force
   have f3: "\<forall>i ia. \<not> (0::int) \<le> i \<or> 0 \<le> i + - 1 * ia \<or> i mod ia = i"
     using mod_pos_pos_trivial by force
   have "(1::int) \<le> 2 ^ LENGTH('b)"
     by simp
   then have "2 ^ LENGTH('b) + - (1::int) * ((- 1 + 2 ^ LENGTH('b)) mod 2 ^ len_of TYPE ('b)) = 1"
     using f3 f2 by blast
   then have f4: "- (1::int) + 2 ^ LENGTH('b) = (- 1 + 2 ^ LENGTH('b)) mod 2 ^ LENGTH('b)"
     by linarith
   have f5: "x \<le> word_of_int (uint (word_of_int (- 1 + 2 ^ LENGTH('b))::'b word))"
     using a1 by force
   have f6: "2 ^ LENGTH('b) + - (1::int) = - 1 + 2 ^ LENGTH('b)"
     by force
   have f7: "- (1::int) * 1 = - 1"
     by auto
   have "\<forall>x0 x1. (x1::int) - x0 = x1 + - 1 * x0"
     by force
   then have "x \<le> 2 ^ LENGTH('b) - 1"
     using f7 f6 f5 f4 by (metis uint_word_of_int wi_homs(2) word_arith_wis(8) word_of_int_2p)
   then have \<open>uint x \<le> uint (2 ^ LENGTH('b) - (1 :: 'a word))\<close>
     by (simp add: word_le_def)
   then have \<open>uint x \<le> 2 ^ LENGTH('b) - 1\<close>
     by (simp add: uint_word_ariths)
       (metis \<open>1 \<le> 2 ^ LENGTH('b)\<close> \<open>uint x \<le> uint (2 ^ LENGTH('b) - 1)\<close> linorder_not_less lt2p_lem uint_1 uint_minus_simple_alt uint_power_lower word_le_def zle_diff1_eq)
   then show ?thesis
     apply (simp add: unsigned_ucast_eq take_bit_word_eq_self_iff)
     apply (meson \<open>x \<le> 2 ^ LENGTH('b) - 1\<close> not_le word_less_sub_le)
     done
 qed
 
 lemma uint_shiftr_eq:
   \<open>uint (w >> n) = uint w div 2 ^ n\<close>
-  by transfer (simp flip: drop_bit_eq_div add: drop_bit_take_bit min_def le_less less_diff_conv)
+  by (rule bit_eqI) (simp flip: drop_bit_eq_div add: bit_simps)
 
 lemma bit_shiftl_word_iff [bit_simps]:
   \<open>bit (w << m) n \<longleftrightarrow> m \<le> n \<and> n < LENGTH('a) \<and> bit w (n - m)\<close>
   for w :: \<open>'a::len word\<close>
-  by (simp add: bit_push_bit_iff not_le)
-
-lemma shiftl_def:
-  \<open>w << n = ((*) 2 ^^ n) w\<close> for w :: \<open>'a::len word\<close>
-proof -
-  have \<open>push_bit n = (((*) 2 ^^ n) :: int \<Rightarrow> int)\<close> for n
-    by (induction n) (simp_all add: fun_eq_iff funpow_swap1, simp add: ac_simps)
-  then show ?thesis
-    by transfer simp
-qed
-
-lemma shiftr_def:
-  \<open>w >> n = ((\<lambda>w. w div 2) ^^ n) w\<close> for w :: \<open>'a::len word\<close>
-proof -
-  have \<open>(\<lambda>w. w div 2) ^^ n = (drop_bit n :: 'a word \<Rightarrow> 'a word)\<close>
-    by (induction n) (simp_all add: drop_bit_half drop_bit_Suc)
-  then show ?thesis
-    by simp
-qed
+  by (simp add: bit_simps)
 
 lemma bit_shiftr_word_iff:
   \<open>bit (w >> m) n \<longleftrightarrow> bit w (m + n)\<close>
   for w :: \<open>'a::len word\<close>
   by (simp add: bit_simps)
 
-lemma sshiftr_eq_funpow_sshiftr1:
-  \<open>w >>> n = (signed_drop_bit (Suc 0) ^^ n) w\<close>
-  apply (rule sym)
-  apply (induction n)
-   apply simp_all
-  done
-
 lemma uint_sshiftr_eq:
   \<open>uint (w >>> n) = take_bit LENGTH('a) (sint w div 2 ^  n)\<close>
   for w :: \<open>'a::len word\<close>
-  by transfer (simp flip: drop_bit_eq_div)
+  by (rule bit_eqI) (auto simp add: bit_simps not_less simp flip: drop_bit_eq_div dest: bit_imp_le_length)
 
 lemma sshiftr_0: "0 >>> n = 0"
-  by (fact signed_drop_bit_of_0)
-
+  by (simp add: sshiftr_def)
+  
 lemma sshiftr_n1: "-1 >>> n = -1"
-  by (fact signed_drop_bit_of_minus_1)
+  by (simp add: sshiftr_def)
 
 lemma bit_sshiftr_word_iff:
   \<open>bit (w >>> m) n \<longleftrightarrow> bit w (if LENGTH('a) - m \<le> n \<and> n < LENGTH('a) then LENGTH('a) - 1 else (m + n))\<close>
   for w :: \<open>'a::len word\<close>
-  by (fact bit_signed_drop_bit_iff)
+  by (fact bit_sshiftr_iff)
 
 lemma nth_sshiftr :
   "bit (w >>> m) n =
     (n < size w \<and> (if n + m \<ge> size w then bit w (size w - 1) else bit w (n + m)))"
   apply (auto simp add: bit_simps word_size ac_simps not_less)
   apply (meson bit_imp_le_length bit_shiftr_word_iff leD)
   done
 
 lemma sshiftr_numeral:
   \<open>(numeral k >>> numeral n :: 'a::len word) =
-    word_of_int (drop_bit (numeral n) (signed_take_bit (LENGTH('a) - 1) (numeral k)))\<close>
-  by (fact signed_drop_bit_word_numeral)
+    word_of_int (signed_take_bit (LENGTH('a) - 1) (numeral k) >> numeral n)\<close>
+  using signed_drop_bit_word_numeral [of n k] by (simp add: sshiftr_def shiftr_def)
 
 lemma sshiftr_div_2n: "sint (w >>> n) = sint w div 2 ^ n"
-  using sint_signed_drop_bit_eq [of n w]
-  by (simp add: drop_bit_eq_div)
+  apply (rule bit_eqI)
+  apply (cases \<open>n < LENGTH('a)\<close>)
+   apply (auto simp add: bit_simps not_less le_diff_conv2 simp flip: drop_bit_eq_div)
+  done
 
 lemma mask_eq:
   \<open>mask n = (1 << n) - (1 :: 'a::len word)\<close>
-  by (simp add: mask_eq_exp_minus_1 push_bit_of_1)
-
-lemma shiftl_0: "(0::'a::len word) << n = 0"
-  by (fact push_bit_of_0)
-
-lemma shiftr_0: "(0::'a::len word) >> n = 0"
-  by (fact drop_bit_of_0)
+  by (simp add: mask_eq_exp_minus_1 shiftl_def)
 
 lemma nth_shiftl': "bit (w << m) n \<longleftrightarrow> n < size w \<and> n >= m \<and> bit w (n - m)"
   for w :: "'a::len word"
-  by transfer (auto simp add: bit_push_bit_iff)
+  by (simp add: bit_simps word_size ac_simps)
 
 lemmas nth_shiftl = nth_shiftl' [unfolded word_size]
 
 lemma nth_shiftr: "bit (w >> m) n = bit w (n + m)"
   for w :: "'a::len word"
   by (simp add: bit_simps ac_simps)
 
 lemma shiftr_div_2n: "uint (shiftr w n) = uint w div 2 ^ n"
   by (fact uint_shiftr_eq)
 
 lemma shiftl_rev: "shiftl w n = word_reverse (shiftr (word_reverse w) n)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma rev_shiftl: "word_reverse w << n = word_reverse (w >> n)"
   by (simp add: shiftl_rev)
 
 lemma shiftr_rev: "w >> n = word_reverse (word_reverse w << n)"
   by (simp add: rev_shiftl)
 
 lemma rev_shiftr: "word_reverse w >> n = word_reverse (w << n)"
   by (simp add: shiftr_rev)
 
 lemmas ucast_up =
   rc1 [simplified rev_shiftr [symmetric] revcast_ucast [symmetric]]
 lemmas ucast_down =
   rc2 [simplified rev_shiftr revcast_ucast [symmetric]]
 
 lemma shiftl_zero_size: "size x \<le> n \<Longrightarrow> x << n = 0"
   for x :: "'a::len word"
-  apply transfer
-  apply (simp add: take_bit_push_bit)
-  done
+  by (simp add: shiftl_def word_size)
 
 lemma shiftl_t2n: "shiftl w n = 2 ^ n * w"
   for w :: "'a::len word"
-  by (simp add: push_bit_eq_mult)
+  by (simp add: shiftl_def push_bit_eq_mult)
 
 lemma word_shift_by_2:
   "x * 4 = (x::'a::len word) << 2"
   by (simp add: shiftl_t2n)
 
 lemma slice_shiftr: "slice n w = ucast (w >> n)"
   apply (rule bit_word_eqI)
   apply (cases \<open>n \<le> LENGTH('b)\<close>)
    apply (auto simp add: bit_slice_iff bit_ucast_iff bit_shiftr_word_iff ac_simps
     dest: bit_imp_le_length)
   done
 
 lemma shiftr_zero_size: "size x \<le> n \<Longrightarrow> x >> n = 0"
   for x :: "'a :: len word"
   by (rule word_eqI) (auto simp add: nth_shiftr dest: test_bit_size)
 
-lemma shiftr_x_0: "x >> 0 = x"
+lemma shiftr_x_0 [simp]: "x >> 0 = x"
   for x :: "'a::len word"
-  by simp
+  by (simp add: shiftr_def)
 
-lemma shiftl_x_0: "x << 0 = x"
+lemma shiftl_x_0 [simp]: "x << 0 = x"
   for x :: "'a::len word"
-  by simp
+  by (simp add: shiftl_def)
 
 lemma shiftl_1: "(1::'a::len word) << n = 2^n"
-  by (fact push_bit_of_1)
+  by (simp add: shiftl_def)
 
-lemma shiftr_1: "(1::'a::len word) >> n = (if n = 0 then 1 else 0)"
-  by simp
+lemma shiftr_1 [simp]: "(1::'a::len word) >> n = (if n = 0 then 1 else 0)"
+  by (simp add: shiftr_def)
 
 lemma shiftl0:
   "x << 0 = (x :: 'a :: len word)"
   by (fact shiftl_x_0)
 
 lemma and_not_mask:
   "w AND NOT (mask n) = (w >> n) << n"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma and_mask:
   "w AND mask n = (w << (size w - n)) >> (size w - n)"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (auto simp add: bit_simps word_size)
 
 lemma shiftr_div_2n_w: "n < size w \<Longrightarrow> w >> n = w div (2^n :: 'a :: len word)"
   apply (unfold word_div_def)
   apply (simp add: uint_2p_alt word_size)
   apply (metis uint_shiftr_eq word_of_int_uint)
   done
 
 lemma le_shiftr:
   "u \<le> v \<Longrightarrow> u >> (n :: nat) \<le> (v :: 'a :: len word) >> n"
+  apply (unfold shiftr_def)
   apply transfer
   apply (simp add: take_bit_drop_bit)
   apply (simp add: drop_bit_eq_div zdiv_mono1)
   done
 
 lemma le_shiftr':
   "\<lbrakk> u >> n \<le> v >> n ; u >> n \<noteq> v >> n \<rbrakk> \<Longrightarrow> (u::'a::len word) \<le> v"
   apply (metis le_cases le_shiftr verit_la_disequality)
   done
 
 lemma shiftr_mask_le:
   "n <= m \<Longrightarrow> mask n >> m = (0 :: 'a::len word)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma shiftr_mask [simp]:
   \<open>mask m >> m = (0::'a::len word)\<close>
   by (rule shiftr_mask_le) simp
 
 lemma le_mask_iff:
   "(w \<le> mask n) = (w >> n = 0)"
   for w :: \<open>'a::len word\<close>
   apply safe
    apply (rule word_le_0_iff [THEN iffD1])
    apply (rule xtrans(3))
     apply (erule_tac [2] le_shiftr)
    apply simp
   apply (rule word_leI)
   apply (rename_tac n')
   apply (drule_tac x = "n' - n" in word_eqD)
   apply (simp add : nth_shiftr word_size bit_simps)
   apply (case_tac "n <= n'")
   by auto
 
 lemma and_mask_eq_iff_shiftr_0:
   "(w AND mask n = w) = (w >> n = 0)"
   for w :: \<open>'a::len word\<close>
-  apply (unfold test_bit_eq_iff [THEN sym])
-  apply (rule iffI)
-   apply (rule ext)
-   apply (rule_tac [2] ext)
-   apply (auto simp add : word_ao_nth nth_shiftr)
-    apply (drule arg_cong)
-    apply (drule iffD2)
-     apply assumption
-    apply (simp add : word_ao_nth)
-   prefer 2
-   apply (simp add : word_size test_bit_bin)
-  apply transfer
-  apply (auto simp add: fun_eq_iff bit_simps)
-  apply (metis add_diff_inverse_nat)
-  done
+  by (simp flip: take_bit_eq_mask add: shiftr_def take_bit_eq_self_iff_drop_bit_eq_0)
 
 lemma mask_shiftl_decompose:
   "mask m << n = mask (m + n) AND NOT (mask n :: 'a::len word)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma shiftl_over_and_dist:
   fixes a::"'a::len word"
   shows "(a AND b) << c = (a << c) AND (b << c)"
-  by (fact push_bit_and)
+  by (unfold shiftl_def) (fact push_bit_and)
 
 lemma shiftr_over_and_dist:
   fixes a::"'a::len word"
   shows "a AND b >> c = (a >> c) AND (b >> c)"
-  by (fact drop_bit_and)
+  by (unfold shiftr_def) (fact drop_bit_and)
 
 lemma sshiftr_over_and_dist:
   fixes a::"'a::len word"
   shows "a AND b >>> c = (a >>> c) AND (b >>> c)"
   apply(rule word_eqI)
   apply(simp add:nth_sshiftr word_ao_nth word_size)
   done
 
 lemma shiftl_over_or_dist:
   fixes a::"'a::len word"
   shows "a OR b << c = (a << c) OR (b << c)"
-  by (fact push_bit_or)
+  by (unfold shiftl_def) (fact push_bit_or)
 
 lemma shiftr_over_or_dist:
   fixes a::"'a::len word"
   shows "a OR b >> c = (a >> c) OR (b >> c)"
-  by (fact drop_bit_or)
+  by (unfold shiftr_def) (fact drop_bit_or)
 
 lemma sshiftr_over_or_dist:
   fixes a::"'a::len word"
   shows "a OR b >>> c = (a >>> c) OR (b >>> c)"
-  apply(rule word_eqI)
-  apply(simp add:nth_sshiftr word_ao_nth word_size)
-  done
+  by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemmas shift_over_ao_dists =
   shiftl_over_or_dist shiftr_over_or_dist
   sshiftr_over_or_dist shiftl_over_and_dist
   shiftr_over_and_dist sshiftr_over_and_dist
 
 lemma shiftl_shiftl:
   fixes a::"'a::len word"
   shows "a << b << c = a << (b + c)"
   apply(rule word_eqI)
   apply(auto simp:word_size nth_shiftl add.commute add.left_commute)
   done
 
 lemma shiftr_shiftr:
   fixes a::"'a::len word"
   shows "a >> b >> c = a >> (b + c)"
   apply(rule word_eqI)
   apply(simp add:word_size nth_shiftr add.left_commute add.commute)
   done
 
 lemma shiftl_shiftr1:
   fixes a::"'a::len word"
   shows "c \<le> b \<Longrightarrow> a << b >> c = a AND (mask (size a - b)) << (b - c)"
   apply (rule word_eqI)
   apply (auto simp add: bit_simps not_le word_size ac_simps)
   done
 
 lemma shiftl_shiftr2:
   fixes a::"'a::len word"
   shows "b < c \<Longrightarrow> a << b >> c = (a >> (c - b)) AND (mask (size a - c))"
   apply(rule word_eqI)
   apply(auto simp:nth_shiftr nth_shiftl word_size word_ao_nth bit_simps)
   done
 
 lemma shiftr_shiftl1:
   fixes a::"'a::len word"
   shows "c \<le> b \<Longrightarrow> a >> b << c = (a >> (b - c)) AND (NOT (mask c))"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma shiftr_shiftl2:
   fixes a::"'a::len word"
   shows "b < c \<Longrightarrow> a >> b << c = (a << (c - b)) AND (NOT (mask c))"
   apply (rule word_eqI)
   apply (auto simp add: bit_simps not_le word_size ac_simps)
   done
 
 lemmas multi_shift_simps =
   shiftl_shiftl shiftr_shiftr
   shiftl_shiftr1 shiftl_shiftr2
   shiftr_shiftl1 shiftr_shiftl2
 
 lemma shiftr_mask2:
   "n \<le> LENGTH('a) \<Longrightarrow> (mask n >> m :: ('a :: len) word) = mask (n - m)"
   by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma word_shiftl_add_distrib:
   fixes x :: "'a :: len word"
   shows "(x + y) << n = (x << n) + (y << n)"
   by (simp add: shiftl_t2n ring_distribs)
 
 lemma mask_shift:
   "(x AND NOT (mask y)) >> y = x >> y"
   for x :: \<open>'a::len word\<close>
   apply (rule bit_eqI)
   apply (simp add: bit_and_iff bit_not_iff bit_shiftr_word_iff bit_mask_iff not_le)
   using bit_imp_le_length apply auto
   done
 
 lemma shiftr_div_2n':
   "unat (w >> n) = unat w div 2 ^ n"
   apply (unfold unat_eq_nat_uint)
   apply (subst shiftr_div_2n)
   apply (subst nat_div_distrib)
    apply simp
   apply (simp add: nat_power_eq)
   done
 
 lemma shiftl_shiftr_id:
   assumes nv: "n < LENGTH('a)"
   and     xv: "x < 2 ^ (LENGTH('a) - n)"
   shows "x << n >> n = (x::'a::len word)"
   apply (simp add: shiftl_t2n)
   apply (rule word_eq_unatI)
   apply (subst shiftr_div_2n')
   apply (cases n)
    apply simp
   apply (subst iffD1 [OF unat_mult_lem])+
    apply (subst unat_power_lower[OF nv])
    apply (rule nat_less_power_trans [OF _ order_less_imp_le [OF nv]])
    apply (rule order_less_le_trans [OF unat_mono [OF xv] order_eq_refl])
    apply (rule unat_power_lower)
    apply simp
   apply (subst unat_power_lower[OF nv])
   apply simp
   done
 
 lemma ucast_shiftl_eq_0:
   fixes w :: "'a :: len word"
   shows "\<lbrakk> n \<ge> LENGTH('b) \<rbrakk> \<Longrightarrow> ucast (w << n) = (0 :: 'b :: len word)"
-  by transfer (simp add: take_bit_push_bit)
+  by (transfer fixing: n) (simp add: take_bit_push_bit)
 
 lemma word_shift_nonzero:
   "\<lbrakk> (x::'a::len word) \<le> 2 ^ m; m + n < LENGTH('a::len); x \<noteq> 0\<rbrakk>
    \<Longrightarrow> x << n \<noteq> 0"
   apply (simp only: word_neq_0_conv word_less_nat_alt
                     shiftl_t2n mod_0 unat_word_ariths
                     unat_power_lower word_le_nat_alt)
   apply (subst mod_less)
    apply (rule order_le_less_trans)
     apply (erule mult_le_mono2)
    apply (subst power_add[symmetric])
    apply (rule power_strict_increasing)
     apply simp
    apply simp
   apply simp
   done
 
 lemma word_shiftr_lt:
   fixes w :: "'a::len word"
   shows "unat (w >> n) < (2 ^ (LENGTH('a) - n))"
   apply (subst shiftr_div_2n')
   apply transfer
   apply (simp flip: drop_bit_eq_div add: drop_bit_nat_eq drop_bit_take_bit)
   done
 
 lemma shiftr_less_t2n':
   "\<lbrakk> x AND mask (n + m) = x; m < LENGTH('a) \<rbrakk> \<Longrightarrow> x >> n < 2 ^ m" for x :: "'a :: len word"
   apply (simp add: word_size mask_eq_iff_w2p [symmetric] flip: take_bit_eq_mask)
   apply transfer
   apply (simp add: take_bit_drop_bit ac_simps)
   done
 
 lemma shiftr_less_t2n:
   "x < 2 ^ (n + m) \<Longrightarrow> x >> n < 2 ^ m" for x :: "'a :: len word"
   apply (rule shiftr_less_t2n')
    apply (erule less_mask_eq)
   apply (rule ccontr)
   apply (simp add: not_less)
   apply (subst (asm) p2_eq_0[symmetric])
   apply (simp add: power_add)
   done
 
 lemma shiftr_eq_0:
   "n \<ge> LENGTH('a) \<Longrightarrow> ((w::'a::len word) >> n) = 0"
   apply (cut_tac shiftr_less_t2n'[of w n 0], simp)
    apply (simp add: mask_eq_iff)
   apply (simp add: lt2p_lem)
   apply simp
   done
 
 lemma shiftl_less_t2n:
   fixes x :: "'a :: len word"
   shows "\<lbrakk> x < (2 ^ (m - n)); m < LENGTH('a) \<rbrakk> \<Longrightarrow> (x << n) < 2 ^ m"
   apply (simp add: word_size mask_eq_iff_w2p [symmetric] flip: take_bit_eq_mask)
   apply transfer
   apply (simp add: take_bit_push_bit)
   done
 
 lemma shiftl_less_t2n':
   "(x::'a::len word) < 2 ^ m \<Longrightarrow> m+n < LENGTH('a) \<Longrightarrow> x << n < 2 ^ (m + n)"
   by (rule shiftl_less_t2n) simp_all
 
 lemma scast_bit_test [simp]:
   "scast ((1 :: 'a::len signed word) << n) = (1 :: 'a word) << n"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma signed_shift_guard_to_word:
   \<open>unat x * 2 ^ y < 2 ^ n \<longleftrightarrow> x = 0 \<or> x < 1 << n >> y\<close>
     if \<open>n < LENGTH('a)\<close> \<open>0 < n\<close>
     for x :: \<open>'a::len word\<close>
 proof (cases \<open>x = 0\<close>)
   case True
   then show ?thesis
     by simp
 next
   case False
   then have \<open>unat x \<noteq> 0\<close>
     by (simp add: unat_eq_0)
   then have \<open>unat x \<ge> 1\<close>
     by simp
   show ?thesis
   proof (cases \<open>y < n\<close>)
     case False
     then have \<open>n \<le> y\<close>
       by simp
     then obtain q where \<open>y = n + q\<close>
       using le_Suc_ex by blast
     moreover have \<open>(2 :: nat) ^ n >> n + q \<le> 1\<close>
-      by (simp add: drop_bit_eq_div power_add)
+      by (simp add: drop_bit_eq_div power_add shiftr_def)
     ultimately show ?thesis
       using \<open>x \<noteq> 0\<close> \<open>unat x \<ge> 1\<close> \<open>n < LENGTH('a)\<close>
-      by (simp add: power_add not_less word_le_nat_alt unat_drop_bit_eq push_bit_of_1)
+      by (simp add: power_add not_less word_le_nat_alt unat_drop_bit_eq shiftr_def shiftl_def)
   next
     case True
     with that have \<open>y < LENGTH('a)\<close>
       by simp
     show ?thesis
     proof (cases \<open>2 ^ n = unat x * 2 ^ y\<close>)
       case True
       moreover have \<open>unat x * 2 ^ y < 2 ^ LENGTH('a)\<close>
         using \<open>n < LENGTH('a)\<close> by (simp flip: True)
       moreover have \<open>(word_of_nat (2 ^ n) :: 'a word) = word_of_nat (unat x * 2 ^ y)\<close>
         using True by simp
       then have \<open>2 ^ n = x * 2 ^ y\<close>
         by simp
       ultimately show ?thesis
         using \<open>y < LENGTH('a)\<close>
-        by (auto simp add: push_bit_of_1 drop_bit_eq_div word_less_nat_alt unat_div unat_word_ariths)
+        by (auto simp add: drop_bit_eq_div word_less_nat_alt unat_div unat_word_ariths
+          shiftr_def shiftl_def)
     next
       case False
       with \<open>y < n\<close> have *: \<open>unat x \<noteq> 2 ^ n div 2 ^ y\<close>
         by (auto simp flip: power_sub power_add)
       have \<open>unat x * 2 ^ y < 2 ^ n \<longleftrightarrow> unat x * 2 ^ y \<le> 2 ^ n\<close>
         using False by (simp add: less_le)
       also have \<open>\<dots> \<longleftrightarrow> unat x \<le> 2 ^ n div 2 ^ y\<close>
         by (simp add: less_eq_div_iff_mult_less_eq)
       also have \<open>\<dots> \<longleftrightarrow> unat x < 2 ^ n div 2 ^ y\<close>
         using * by (simp add: less_le)
       finally show ?thesis
       using that \<open>x \<noteq> 0\<close> by (simp flip: push_bit_eq_mult drop_bit_eq_div
-        add: push_bit_of_1 unat_drop_bit_eq word_less_iff_unsigned [where ?'a = nat])
+        add: shiftr_def shiftl_def unat_drop_bit_eq word_less_iff_unsigned [where ?'a = nat])
     qed
   qed
 qed
 
 lemma shiftr_not_mask_0:
   "n+m \<ge> LENGTH('a :: len) \<Longrightarrow> ((w::'a::len word) >> n) AND NOT (mask m) = 0"
   by (rule bit_word_eqI) (auto simp add: bit_simps word_size dest: bit_imp_le_length)
 
 lemma shiftl_mask_is_0[simp]:
   "(x << n) AND mask n = 0"
   for x :: \<open>'a::len word\<close>
-  by (simp flip: take_bit_eq_mask add: take_bit_push_bit)
+  by (simp flip: take_bit_eq_mask add: take_bit_push_bit shiftl_def)
 
 lemma rshift_sub_mask_eq:
   "(a >> (size a - b)) AND mask b = a >> (size a - b)"
   for a :: \<open>'a::len word\<close>
   using shiftl_shiftr2[where a=a and b=0 and c="size a - b"]
   apply (cases "b < size a")
    apply simp
   apply (simp add: linorder_not_less mask_eq_decr_exp word_size
                    p2_eq_0[THEN iffD2])
   done
 
 lemma shiftl_shiftr3:
   "b \<le> c \<Longrightarrow> a << b >> c = (a >> c - b) AND mask (size a - c)"
   for a :: \<open>'a::len word\<close>
   apply (cases "b = c")
    apply (simp add: shiftl_shiftr1)
   apply (simp add: shiftl_shiftr2)
   done
 
 lemma and_mask_shiftr_comm:
   "m \<le> size w \<Longrightarrow> (w AND mask m) >> n = (w >> n) AND mask (m-n)"
   for w :: \<open>'a::len word\<close>
   by (simp add: and_mask shiftr_shiftr) (simp add: word_size shiftl_shiftr3)
 
 lemma and_mask_shiftl_comm:
   "m+n \<le> size w \<Longrightarrow> (w AND mask m) << n = (w << n) AND mask (m+n)"
   for w :: \<open>'a::len word\<close>
   by (simp add: and_mask word_size shiftl_shiftl) (simp add: shiftl_shiftr1)
 
 lemma le_mask_shiftl_le_mask: "s = m + n \<Longrightarrow> x \<le> mask n \<Longrightarrow> x << m \<le> mask s"
   for x :: \<open>'a::len word\<close>
   by (simp add: le_mask_iff shiftl_shiftr3)
 
 lemma word_and_1_shiftl:
   "x AND (1 << n) = (if bit x n then (1 << n) else 0)" for x :: "'a :: len word"
   apply (rule bit_word_eqI; transfer)
   apply (auto simp add: bit_simps not_le ac_simps)
   done
 
 lemmas word_and_1_shiftls'
     = word_and_1_shiftl[where n=0]
       word_and_1_shiftl[where n=1]
       word_and_1_shiftl[where n=2]
 
 lemmas word_and_1_shiftls = word_and_1_shiftls' [simplified]
 
 lemma word_and_mask_shiftl:
   "x AND (mask n << m) = ((x >> m) AND mask n) << m"
   for x :: \<open>'a::len word\<close>
   apply (rule bit_word_eqI; transfer)
   apply (auto simp add: bit_simps not_le ac_simps)
   done
 
 lemma shift_times_fold:
   "(x :: 'a :: len word) * (2 ^ n) << m = x << (m + n)"
   by (simp add: shiftl_t2n ac_simps power_add)
 
 lemma of_bool_nth:
   "of_bool (bit x v) = (x >> v) AND 1"
   for x :: \<open>'a::len word\<close>
-  by (simp add: bit_iff_odd_drop_bit word_and_1)
+  by (simp add: bit_iff_odd_drop_bit word_and_1 shiftr_def)
 
 lemma shiftr_mask_eq:
   "(x >> n) AND mask (size x - n) = x >> n" for x :: "'a :: len word"
   apply (simp flip: take_bit_eq_mask)
   apply transfer
   apply (simp add: take_bit_drop_bit)
   done
 
 lemma shiftr_mask_eq':
   "m = (size x - n) \<Longrightarrow> (x >> n) AND mask m = x >> n" for x :: "'a :: len word"
   by (simp add: shiftr_mask_eq)
 
 lemma and_eq_0_is_nth:
   fixes x :: "'a :: len word"
   shows "y = 1 << n \<Longrightarrow> ((x AND y) = 0) = (\<not> (bit x n))"
-  by (simp add: and_exp_eq_0_iff_not_bit push_bit_of_1)
+  by (simp add: and_exp_eq_0_iff_not_bit shiftl_def)
 
 lemma word_shift_zero:
   "\<lbrakk> x << n = 0; x \<le> 2^m; m + n < LENGTH('a)\<rbrakk> \<Longrightarrow> (x::'a::len word) = 0"
   apply (rule ccontr)
   apply (drule (2) word_shift_nonzero)
   apply simp
   done
 
 lemma mask_shift_and_negate[simp]:"(w AND mask n << m) AND NOT (mask n << m) = 0"
   for w :: \<open>'a::len word\<close>
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 (* The seL4 bitfield generator produces functions containing mask and shift operations, such that
  * invoking two of them consecutively can produce something like the following.
  *)
 lemma bitfield_op_twice:
   "(x AND NOT (mask n << m) OR ((y AND mask n) << m)) AND NOT (mask n << m) = x AND NOT (mask n << m)"
   for x :: \<open>'a::len word\<close>
   by (induct n arbitrary: m) (auto simp: word_ao_dist)
 
 lemma bitfield_op_twice'':
   "\<lbrakk>NOT a = b << c; \<exists>x. b = mask x\<rbrakk> \<Longrightarrow> (x AND a OR (y AND b << c)) AND a = x AND a"
   for a b :: \<open>'a::len word\<close>
   apply clarsimp
   apply (cut_tac n=xa and m=c and x=x and y=y in bitfield_op_twice)
   apply (clarsimp simp:mask_eq_decr_exp)
   apply (drule not_switch)
   apply clarsimp
   done
 
 lemma shiftr1_unfold: "x div 2 = x >> 1"
-  by (simp add: drop_bit_eq_div)
+  by (simp add: drop_bit_eq_div shiftr_def)
 
 lemma shiftr1_is_div_2: "(x::('a::len) word) >> 1 = x div 2"
-  by (simp add: drop_bit_eq_div)
+  by (simp add: drop_bit_eq_div shiftr_def)
 
 lemma shiftl1_is_mult: "(x << 1) = (x :: 'a::len word) * 2"
   by (metis One_nat_def mult_2 mult_2_right one_add_one
         power_0 power_Suc shiftl_t2n)
 
 lemma shiftr1_lt:"x \<noteq> 0 \<Longrightarrow> (x::('a::len) word) >> 1 < x"
   apply (subst shiftr1_is_div_2)
   apply (rule div_less_dividend_word)
    apply simp+
   done
 
 lemma shiftr1_0_or_1:"(x::('a::len) word) >> 1 = 0 \<Longrightarrow> x = 0 \<or> x = 1"
   apply (subst (asm) shiftr1_is_div_2)
   apply (drule word_less_div)
   apply (case_tac "LENGTH('a) = 1")
    apply (simp add:degenerate_word)
   apply (erule disjE)
    apply (subgoal_tac "(2::'a word) \<noteq> 0")
     apply simp
    apply (rule not_degenerate_imp_2_neq_0)
    apply (subgoal_tac "LENGTH('a) \<noteq> 0")
     apply arith
    apply simp
   apply (rule x_less_2_0_1', simp+)
   done
 
 lemma shiftr1_irrelevant_lsb: "bit (x::('a::len) word) 0 \<or> x >> 1 = (x + 1) >> 1"
   apply (cases \<open>LENGTH('a)\<close>; transfer)
    apply (simp_all add: take_bit_drop_bit)
   apply (simp add: drop_bit_take_bit drop_bit_Suc)
   done
 
 lemma shiftr1_0_imp_only_lsb:"((x::('a::len) word) + 1) >> 1 = 0 \<Longrightarrow> x = 0 \<or> x + 1 = 0"
   by (metis One_nat_def shiftr1_0_or_1 word_less_1 word_overflow)
 
 lemma shiftr1_irrelevant_lsb': "\<not> (bit (x::('a::len) word) 0) \<Longrightarrow> x >> 1 = (x + 1) >> 1"
   by (metis shiftr1_irrelevant_lsb)
 
 (* Perhaps this one should be a simp lemma, but it seems a little dangerous. *)
 lemma cast_chunk_assemble_id:
   "\<lbrakk>n = LENGTH('a::len); m = LENGTH('b::len); n * 2 = m\<rbrakk> \<Longrightarrow>
   (((ucast ((ucast (x::'b word))::'a word))::'b word) OR (((ucast ((ucast (x >> n))::'a word))::'b word) << n)) = x"
   apply (subgoal_tac "((ucast ((ucast (x >> n))::'a word))::'b word) = x >> n")
    apply clarsimp
    apply (subst and_not_mask[symmetric])
    apply (subst ucast_ucast_mask)
    apply (subst word_ao_dist2[symmetric])
    apply clarsimp
   apply (rule ucast_ucast_len)
   apply (rule shiftr_less_t2n')
    apply (subst and_mask_eq_iff_le_mask)
    apply (simp_all add: mask_eq_decr_exp flip: mult_2_right)
   apply (metis add_diff_cancel_left' len_gt_0 mult_2_right zero_less_diff)
   done
 
 lemma cast_chunk_scast_assemble_id:
   "\<lbrakk>n = LENGTH('a::len); m = LENGTH('b::len); n * 2 = m\<rbrakk> \<Longrightarrow>
   (((ucast ((scast (x::'b word))::'a word))::'b word) OR
    (((ucast ((scast (x >> n))::'a word))::'b word) << n)) = x"
   apply (subgoal_tac "((scast x)::'a word) = ((ucast x)::'a word)")
    apply (subgoal_tac "((scast (x >> n))::'a word) = ((ucast (x >> n))::'a word)")
     apply (simp add:cast_chunk_assemble_id)
    apply (subst down_cast_same[symmetric], subst is_down, arith, simp)+
   done
 
 lemma unat_shiftr_less_t2n:
   fixes x :: "'a :: len word"
   shows "unat x < 2 ^ (n + m) \<Longrightarrow> unat (x >> n) < 2 ^ m"
   by (simp add: shiftr_div_2n' power_add mult.commute less_mult_imp_div_less)
 
 lemma ucast_less_shiftl_helper:
   "\<lbrakk> LENGTH('b) + 2 < LENGTH('a); 2 ^ (LENGTH('b) + 2) \<le> n\<rbrakk>
     \<Longrightarrow> (ucast (x :: 'b::len word) << 2) < (n :: 'a::len word)"
   apply (erule order_less_le_trans[rotated])
   using ucast_less[where x=x and 'a='a]
   apply (simp only: shiftl_t2n field_simps)
   apply (rule word_less_power_trans2; simp)
   done
 
 (* negating a mask which has been shifted to the very left *)
 lemma NOT_mask_shifted_lenword:
   "NOT (mask len << (LENGTH('a) - len) ::'a::len word) = mask (LENGTH('a) - len)"
   by (rule bit_word_eqI)
-    (auto simp add: word_size bit_not_iff bit_push_bit_iff bit_mask_iff)
+    (auto simp add: word_size bit_not_iff bit_push_bit_iff bit_mask_iff shiftl_def)
 
 (* Comparisons between different word sizes. *)
 
 lemma shiftr_less:
   "(w::'a::len word) < k \<Longrightarrow> w >> n < k"
   by (metis div_le_dividend le_less_trans shiftr_div_2n' unat_arith_simps(2))
 
 lemma word_and_notzeroD:
   "w AND w' \<noteq> 0 \<Longrightarrow> w \<noteq> 0 \<and> w' \<noteq> 0"
   by auto
 
 lemma shiftr_le_0:
   "unat (w::'a::len word) < 2 ^ n \<Longrightarrow> w >> n = (0::'a::len word)"
-  apply (auto simp add: take_bit_word_eq_self_iff word_less_nat_alt
-    simp flip: take_bit_eq_self_iff_drop_bit_eq_0)
-  apply (rule ccontr)
-  apply (simp add: not_le)
-  done
+  by (auto simp add: take_bit_word_eq_self_iff word_less_nat_alt shiftr_def
+    simp flip: take_bit_eq_self_iff_drop_bit_eq_0 intro: ccontr)
 
 lemma of_nat_shiftl:
   "(of_nat x << n) = (of_nat (x * 2 ^ n) :: ('a::len) word)"
 proof -
   have "(of_nat x::'a word) << n = of_nat (2 ^ n) * of_nat x"
     using shiftl_t2n by (metis word_unat_power)
   thus ?thesis by simp
 qed
 
 lemma shiftl_1_not_0:
   "n < LENGTH('a) \<Longrightarrow> (1::'a::len word) << n \<noteq> 0"
   by (simp add: shiftl_t2n)
 
 (* continue sorting out from here *)
 
 (* usually: x,y = (len_of TYPE ('a)) *)
 lemma bitmagic_zeroLast_leq_or1Last:
   "(a::('a::len) word) AND (mask len << x - len) \<le> a OR mask (y - len)"
   by (meson le_word_or2 order_trans word_and_le2)
 
 lemma zero_base_lsb_imp_set_eq_as_bit_operation:
   fixes base ::"'a::len word"
   assumes valid_prefix: "mask (LENGTH('a) - len) AND base = 0"
   shows "(base = NOT (mask (LENGTH('a) - len)) AND a) \<longleftrightarrow>
          (a \<in> {base .. base OR mask (LENGTH('a) - len)})"
 proof
   have helper3: "x OR y = x OR y AND NOT x" for x y ::"'a::len word" by (simp add: word_oa_dist2)
   from assms show "base = NOT (mask (LENGTH('a) - len)) AND a \<Longrightarrow>
                     a \<in> {base..base OR mask (LENGTH('a) - len)}"
     apply(simp add: word_and_le1)
     apply(metis helper3 le_word_or2 word_bw_comms(1) word_bw_comms(2))
   done
 next
   assume "a \<in> {base..base OR mask (LENGTH('a) - len)}"
   hence a: "base \<le> a \<and> a \<le> base OR mask (LENGTH('a) - len)" by simp
   show "base = NOT (mask (LENGTH('a) - len)) AND a"
   proof -
     have f2: "\<forall>x\<^sub>0. base AND NOT (mask x\<^sub>0) \<le> a AND NOT (mask x\<^sub>0)"
       using a neg_mask_mono_le by blast
     have f3: "\<forall>x\<^sub>0. a AND NOT (mask x\<^sub>0) \<le> (base OR mask (LENGTH('a) - len)) AND NOT (mask x\<^sub>0)"
       using a neg_mask_mono_le by blast
     have f4: "base = base AND NOT (mask (LENGTH('a) - len))"
       using valid_prefix by (metis mask_eq_0_eq_x word_bw_comms(1))
     hence f5: "\<forall>x\<^sub>6. (base OR x\<^sub>6) AND NOT (mask (LENGTH('a) - len)) =
                       base OR x\<^sub>6 AND NOT (mask (LENGTH('a) - len))"
       using word_ao_dist by (metis)
     have f6: "\<forall>x\<^sub>2 x\<^sub>3. a AND NOT (mask x\<^sub>2) \<le> x\<^sub>3 \<or>
                       \<not> (base OR mask (LENGTH('a) - len)) AND NOT (mask x\<^sub>2) \<le> x\<^sub>3"
       using f3 dual_order.trans by auto
     have "base = (base OR mask (LENGTH('a) - len)) AND NOT (mask (LENGTH('a) - len))"
       using f5 by auto
     hence "base = a AND NOT (mask (LENGTH('a) - len))"
       using f2 f4 f6 by (metis eq_iff)
     thus "base = NOT (mask (LENGTH('a) - len)) AND a"
       by (metis word_bw_comms(1))
   qed
 qed
 
 lemma of_nat_eq_signed_scast:
   "(of_nat x = (y :: ('a::len) signed word))
    = (of_nat x = (scast y :: 'a word))"
   by (metis scast_of_nat scast_scast_id(2))
 
 lemma word_aligned_add_no_wrap_bounded:
   "\<lbrakk> w + 2^n \<le> x; w + 2^n \<noteq> 0; is_aligned w n \<rbrakk> \<Longrightarrow> (w::'a::len word) < x"
   by (blast dest: is_aligned_no_overflow le_less_trans word_leq_le_minus_one)
 
 lemma mask_Suc:
   "mask (Suc n) = (2 :: 'a::len word) ^ n + mask n"
   by (simp add: mask_eq_decr_exp)
 
 lemma mask_mono:
   "sz' \<le> sz \<Longrightarrow> mask sz' \<le> (mask sz :: 'a::len word)"
   by (simp add: le_mask_iff shiftr_mask_le)
 
 lemma aligned_mask_disjoint:
   "\<lbrakk> is_aligned (a :: 'a :: len word) n; b \<le> mask n \<rbrakk> \<Longrightarrow> a AND b = 0"
   by (metis and_zero_eq is_aligned_mask le_mask_imp_and_mask word_bw_lcs(1))
 
 lemma word_and_or_mask_aligned:
   "\<lbrakk> is_aligned a n; b \<le> mask n \<rbrakk> \<Longrightarrow> a + b = a OR b"
   by (simp add: aligned_mask_disjoint word_plus_and_or_coroll)
 
 lemma word_and_or_mask_aligned2:
   \<open>is_aligned b n \<Longrightarrow> a \<le> mask n \<Longrightarrow> a + b = a OR b\<close>
   using word_and_or_mask_aligned [of b n a] by (simp add: ac_simps)
 
 lemma is_aligned_ucastI:
   "is_aligned w n \<Longrightarrow> is_aligned (ucast w) n"
   by (simp add: bit_ucast_iff is_aligned_nth)
 
 lemma ucast_le_maskI:
   "a \<le> mask n \<Longrightarrow> UCAST('a::len \<rightarrow> 'b::len) a \<le> mask n"
   by (metis and_mask_eq_iff_le_mask ucast_and_mask)
 
 lemma ucast_add_mask_aligned:
   "\<lbrakk> a \<le> mask n; is_aligned b n \<rbrakk> \<Longrightarrow> UCAST ('a::len \<rightarrow> 'b::len) (a + b) = ucast a + ucast b"
   by (metis add.commute is_aligned_ucastI ucast_le_maskI ucast_or_distrib word_and_or_mask_aligned)
 
 lemma ucast_shiftl:
   "LENGTH('b) \<le> LENGTH ('a) \<Longrightarrow> UCAST ('a::len \<rightarrow> 'b::len) x << n = ucast (x << n)"
-  by word_eqI_solve
+  by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma ucast_leq_mask:
   "LENGTH('a) \<le> n \<Longrightarrow> ucast (x::'a::len word) \<le> mask n"
   apply (simp add: less_eq_mask_iff_take_bit_eq_self)
   apply transfer
   apply (simp add: ac_simps)
   done
 
 lemma shiftl_inj:
-  "\<lbrakk> x << n = y << n; x \<le> mask (LENGTH('a)-n); y \<le> mask (LENGTH('a)-n) \<rbrakk> \<Longrightarrow>
-   x = (y :: 'a :: len word)"
-  apply word_eqI
-  apply (rename_tac n')
-  apply (case_tac "LENGTH('a) - n \<le> n'", simp)
-  by (metis add.commute add.right_neutral diff_add_inverse le_diff_conv linorder_not_less zero_order(1))
+  \<open>x = y\<close>
+    if \<open>x << n = y << n\<close> \<open>x \<le> mask (LENGTH('a) - n)\<close> \<open>y \<le> mask (LENGTH('a) - n)\<close>
+    for x y :: \<open>'a::len word\<close>
+proof (cases \<open>n < LENGTH('a)\<close>)
+  case False
+  with that show ?thesis
+    by simp
+next
+  case True
+  moreover from that have \<open>take_bit (LENGTH('a) - n) x = x\<close> \<open>take_bit (LENGTH('a) - n) y = y\<close>
+    by (simp_all add: less_eq_mask_iff_take_bit_eq_self)
+  ultimately show ?thesis
+    using \<open>x << n = y << n\<close> by (metis diff_less gr_implies_not0 linorder_cases linorder_not_le shiftl_shiftr_id shiftl_x_0 take_bit_word_eq_self_iff)
+qed
 
 lemma distinct_word_add_ucast_shift_inj:
   \<open>p' = p \<and> off' = off\<close>
   if *: \<open>p + (UCAST('a::len \<rightarrow> 'b::len) off << n) = p' + (ucast off' << n)\<close>
     and \<open>is_aligned p n'\<close> \<open>is_aligned p' n'\<close> \<open>n' = n + LENGTH('a)\<close> \<open>n' < LENGTH('b)\<close>
 proof -
   from \<open>n' = n + LENGTH('a)\<close>
   have [simp]: \<open>n' - n = LENGTH('a)\<close> \<open>n + LENGTH('a) = n'\<close>
     by simp_all
   from \<open>is_aligned p n'\<close> obtain q
     where p: \<open>p = push_bit n' (word_of_nat q)\<close> \<open>q < 2 ^ (LENGTH('b) - n')\<close>
     by (rule is_alignedE')
   from \<open>is_aligned p' n'\<close> obtain q'
     where p': \<open>p' = push_bit n' (word_of_nat q')\<close> \<open>q' < 2 ^ (LENGTH('b) - n')\<close>
     by (rule is_alignedE')
   define m :: nat where \<open>m = unat off\<close>
   then have off: \<open>off = word_of_nat m\<close>
     by simp
   define m' :: nat where \<open>m' = unat off'\<close>
   then have off': \<open>off' = word_of_nat m'\<close>
     by simp
   have \<open>push_bit n' q + take_bit n' (push_bit n m) < 2 ^ LENGTH('b)\<close>
     by (metis id_apply is_aligned_no_wrap''' of_nat_eq_id of_nat_push_bit p(1) p(2) take_bit_nat_eq_self_iff take_bit_nat_less_exp take_bit_push_bit that(2) that(5) unsigned_of_nat)
   moreover have \<open>push_bit n' q' + take_bit n' (push_bit n m') < 2 ^ LENGTH('b)\<close>
     by (metis \<open>n' - n = LENGTH('a)\<close> id_apply is_aligned_no_wrap''' m'_def of_nat_eq_id of_nat_push_bit off' p'(1) p'(2) take_bit_nat_eq_self_iff take_bit_push_bit that(3) that(5) unsigned_of_nat)
   ultimately have \<open>push_bit n' q + take_bit n' (push_bit n m) = push_bit n' q' + take_bit n' (push_bit n m')\<close>
-    using * by (simp add: p p' off off' push_bit_of_nat push_bit_take_bit word_of_nat_inj unsigned_of_nat flip: of_nat_add)
+    using * by (simp add: p p' off off' push_bit_of_nat push_bit_take_bit word_of_nat_inj unsigned_of_nat shiftl_def flip: of_nat_add)
   then have \<open>int (push_bit n' q + take_bit n' (push_bit n m))
     = int (push_bit n' q' + take_bit n' (push_bit n m'))\<close>
     by simp
   then have \<open>concat_bit n' (int (push_bit n m)) (int q)
     = concat_bit n' (int (push_bit n m')) (int q')\<close>
     by (simp add: of_nat_push_bit of_nat_take_bit concat_bit_eq)
   then show ?thesis
     by (simp add: p p' off off' take_bit_of_nat take_bit_push_bit word_of_nat_eq_iff concat_bit_eq_iff)
       (simp add: push_bit_eq_mult)
 qed
 
 lemma word_upto_Nil:
   "y < x \<Longrightarrow> [x .e. y ::'a::len word] = []"
   by (simp add: upto_enum_red not_le word_less_nat_alt)
 
 lemma word_enum_decomp_elem:
   assumes "[x .e. (y ::'a::len word)] = as @ a # bs"
   shows "x \<le> a \<and> a \<le> y"
 proof -
   have "set as \<subseteq> set [x .e. y] \<and> a \<in> set [x .e. y]"
     using assms by (auto dest: arg_cong[where f=set])
   then show ?thesis by auto
 qed
 
 lemma word_enum_prefix:
   "[x .e. (y ::'a::len word)] = as @ a # bs \<Longrightarrow> as = (if x < a then [x .e. a - 1] else [])"
   apply (induct as arbitrary: x; clarsimp)
    apply (case_tac "x < y")
     prefer 2
     apply (case_tac "x = y", simp)
     apply (simp add: not_less)
     apply (drule (1) dual_order.not_eq_order_implies_strict)
     apply (simp add: word_upto_Nil)
    apply (simp add: word_upto_Cons_eq)
   apply (case_tac "x < y")
    prefer 2
    apply (case_tac "x = y", simp)
    apply (simp add: not_less)
    apply (drule (1) dual_order.not_eq_order_implies_strict)
    apply (simp add: word_upto_Nil)
   apply (clarsimp simp: word_upto_Cons_eq)
   apply (frule word_enum_decomp_elem)
   apply clarsimp
   apply (rule conjI)
    prefer 2
    apply (subst word_Suc_le[symmetric]; clarsimp)
   apply (drule meta_spec)
   apply (drule (1) meta_mp)
   apply clarsimp
   apply (rule conjI; clarsimp)
   apply (subst (2) word_upto_Cons_eq)
    apply unat_arith
   apply simp
   done
 
 lemma word_enum_decomp_set:
   "[x .e. (y ::'a::len word)] = as @ a # bs \<Longrightarrow> a \<notin> set as"
   by (metis distinct_append distinct_enum_upto' not_distinct_conv_prefix)
 
 lemma word_enum_decomp:
   assumes "[x .e. (y ::'a::len word)] = as @ a # bs"
   shows "x \<le> a \<and> a \<le> y \<and> a \<notin> set as \<and> (\<forall>z \<in> set as. x \<le> z \<and> z \<le> y)"
 proof -
   from assms
   have "set as \<subseteq> set [x .e. y] \<and> a \<in> set [x .e. y]"
     by (auto dest: arg_cong[where f=set])
   with word_enum_decomp_set[OF assms]
   show ?thesis by auto
 qed
 
 lemma of_nat_unat_le_mask_ucast:
   "\<lbrakk>of_nat (unat t) = w; t \<le> mask LENGTH('a)\<rbrakk> \<Longrightarrow> t = UCAST('a::len \<rightarrow> 'b::len) w"
   by (clarsimp simp: ucast_nat_def ucast_ucast_mask simp flip: and_mask_eq_iff_le_mask)
 
 lemma less_diff_gt0:
   "a < b \<Longrightarrow> (0 :: 'a :: len word) < b - a"
   by unat_arith
 
 lemma unat_plus_gt:
   "unat ((a :: 'a :: len word) + b) \<le> unat a + unat b"
   by (clarsimp simp: unat_plus_if_size)
 
 lemma const_less:
   "\<lbrakk> (a :: 'a :: len word) - 1 < b; a \<noteq> b \<rbrakk> \<Longrightarrow> a < b"
   by (metis less_1_simp word_le_less_eq)
 
 lemma add_mult_aligned_neg_mask:
   \<open>(x + y * m) AND NOT(mask n) = (x AND NOT(mask n)) + y * m\<close>
   if \<open>m AND (2 ^ n - 1) = 0\<close>
   for x y m :: \<open>'a::len word\<close>
   by (metis (no_types, opaque_lifting)
     add.assoc add.commute add.right_neutral add_uminus_conv_diff
    mask_eq_decr_exp mask_eqs(2) mask_eqs(6) mult.commute mult_zero_left
    subtract_mask(1) that)
 
 lemma unat_of_nat_minus_1:
   "\<lbrakk> n < 2 ^ LENGTH('a); n \<noteq> 0 \<rbrakk> \<Longrightarrow> unat ((of_nat n:: 'a :: len word) - 1) = n - 1"
   by (simp add: of_nat_diff unat_eq_of_nat)
 
 lemma word_eq_zeroI:
   "a \<le> a - 1 \<Longrightarrow> a = 0" for a :: "'a :: len word"
   by (simp add: word_must_wrap)
 
 lemma word_add_format:
   "(-1 :: 'a :: len  word) + b + c = b + (c - 1)"
   by simp
 
 lemma upto_enum_word_nth:
   "\<lbrakk> i \<le> j; k \<le> unat (j - i) \<rbrakk> \<Longrightarrow> [i .e. j] ! k = i + of_nat k"
   apply (clarsimp simp: upto_enum_def nth_append)
   apply (clarsimp simp: word_le_nat_alt[symmetric])
   apply (rule conjI, clarsimp)
    apply (subst toEnum_of_nat, unat_arith)
    apply unat_arith
   apply (clarsimp simp: not_less unat_sub[symmetric])
   apply unat_arith
   done
 
 lemma upto_enum_step_nth:
   "\<lbrakk> a \<le> c; n \<le> unat ((c - a) div (b - a)) \<rbrakk>
    \<Longrightarrow> [a, b .e. c] ! n = a + of_nat n * (b - a)"
   by (clarsimp simp: upto_enum_step_def not_less[symmetric] upto_enum_word_nth)
 
 lemma upto_enum_inc_1_len:
   "a < - 1 \<Longrightarrow> [(0 :: 'a :: len word) .e. 1 + a] = [0 .e. a] @ [1 + a]"
   apply (simp add: upto_enum_word)
   apply (subgoal_tac "unat (1+a) = 1 + unat a")
    apply simp
   apply (subst unat_plus_simple[THEN iffD1])
    apply (metis add.commute no_plus_overflow_neg olen_add_eqv)
   apply unat_arith
   done
 
 lemma neg_mask_add:
   "y AND mask n = 0 \<Longrightarrow> x + y AND NOT(mask n) = (x AND NOT(mask n)) + y"
   for x y :: \<open>'a::len word\<close>
   by (clarsimp simp: mask_out_sub_mask mask_eqs(7)[symmetric] mask_twice)
 
 lemma shiftr_shiftl_shiftr[simp]:
   "(x :: 'a :: len word) >> a << a >> a = x >> a"
-  by word_eqI_solve
+  by (rule bit_word_eqI) (auto simp add: bit_simps dest: bit_imp_le_length)
 
 lemma add_right_shift:
   "\<lbrakk> x AND mask n = 0; y AND mask n = 0; x \<le> x + y \<rbrakk>
    \<Longrightarrow> (x + y :: ('a :: len) word) >> n = (x >> n) + (y >> n)"
   apply (simp add: no_olen_add_nat is_aligned_mask[symmetric])
   apply (simp add: unat_arith_simps shiftr_div_2n' split del: if_split)
   apply (subst if_P)
    apply (erule order_le_less_trans[rotated])
    apply (simp add: add_mono)
   apply (simp add: shiftr_div_2n' is_aligned_iff_dvd_nat)
   done
 
 lemma sub_right_shift:
   "\<lbrakk> x AND mask n = 0; y AND mask n = 0; y \<le> x \<rbrakk>
    \<Longrightarrow> (x - y) >> n = (x >> n :: 'a :: len word) - (y >> n)"
   using add_right_shift[where x="x - y" and y=y and n=n]
   by (simp add: aligned_sub_aligned is_aligned_mask[symmetric] word_sub_le)
 
 lemma and_and_mask_simple:
   "y AND mask n = mask n \<Longrightarrow> (x AND y) AND mask n = x AND mask n"
   by (simp add: ac_simps)
 
 lemma and_and_mask_simple_not:
   "y AND mask n = 0 \<Longrightarrow> (x AND y) AND mask n = 0"
   by (simp add: ac_simps)
 
 lemma word_and_le':
   "b \<le> c \<Longrightarrow> (a :: 'a :: len word) AND b \<le> c"
   by (metis word_and_le1 order_trans)
 
 lemma word_and_less':
   "b < c \<Longrightarrow> (a :: 'a :: len word) AND b < c"
   by transfer simp
 
 lemma shiftr_w2p:
   "x < LENGTH('a) \<Longrightarrow> 2 ^ x = (2 ^ (LENGTH('a) - 1) >> (LENGTH('a) - 1 - x) :: 'a :: len word)"
-  by word_eqI_solve
+  by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma t2p_shiftr:
   "\<lbrakk> b \<le> a; a < LENGTH('a) \<rbrakk> \<Longrightarrow> (2 :: 'a :: len word) ^ a >> b = 2 ^ (a - b)"
-  by word_eqI_solve
+  by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma scast_1[simp]:
   "scast (1 :: 'a :: len signed word) = (1 :: 'a word)"
   by simp
 
 lemma unsigned_uminus1 [simp]:
   \<open>(unsigned (-1::'b::len word)::'c::len word) = mask LENGTH('b)\<close>
-  by (rule bit_word_eqI) (auto simp add: bit_simps)
+  by (fact unsigned_minus_1_eq_mask)
 
 lemma ucast_ucast_mask_eq:
   "\<lbrakk> UCAST('a::len \<rightarrow> 'b::len) x = y; x AND mask LENGTH('b) = x \<rbrakk> \<Longrightarrow> x = ucast y"
   by (drule sym) (simp flip: take_bit_eq_mask add: unsigned_ucast_eq)
 
 lemma ucast_up_eq:
   "\<lbrakk> ucast x = (ucast y::'b::len word); LENGTH('a) \<le> LENGTH ('b) \<rbrakk>
    \<Longrightarrow> ucast x = (ucast y::'a::len word)"
-  by word_eqI_solve
+  by (simp add: word_eq_iff bit_simps)
 
 lemma ucast_up_neq:
   "\<lbrakk> ucast x \<noteq> (ucast y::'b::len word); LENGTH('b) \<le> LENGTH ('a) \<rbrakk>
    \<Longrightarrow> ucast x \<noteq> (ucast y::'a::len word)"
   by (fastforce dest: ucast_up_eq)
 
 lemma mask_AND_less_0:
   "\<lbrakk> x AND mask n = 0; m \<le> n \<rbrakk> \<Longrightarrow> x AND mask m = 0"
   for x :: \<open>'a::len word\<close>
   by (metis mask_twice2 word_and_notzeroD)
 
 lemma mask_len_id [simp]:
   "(x :: 'a :: len word) AND mask LENGTH('a) = x"
   using uint_lt2p [of x] by (simp add: mask_eq_iff)
 
 lemma scast_ucast_down_same:
   "LENGTH('b) \<le> LENGTH('a) \<Longrightarrow> SCAST('a \<rightarrow> 'b) = UCAST('a::len \<rightarrow> 'b::len)"
   by (simp add: down_cast_same is_down)
 
 lemma word_aligned_0_sum:
   "\<lbrakk> a + b = 0; is_aligned (a :: 'a :: len word) n; b \<le> mask n; n < LENGTH('a) \<rbrakk>
    \<Longrightarrow> a = 0 \<and> b = 0"
   by (simp add: word_plus_and_or_coroll aligned_mask_disjoint word_or_zero)
 
 lemma mask_eq1_nochoice:
   "\<lbrakk> LENGTH('a) > 1; (x :: 'a :: len word) AND 1 = x \<rbrakk> \<Longrightarrow> x = 0 \<or> x = 1"
   by (metis word_and_1)
 
 lemma shiftr_and_eq_shiftl:
   "(w >> n) AND x = y \<Longrightarrow> w AND (x << n) = (y << n)" for y :: "'a:: len word"
   apply (drule sym)
   apply simp
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps)
   done
 
 lemma add_mask_lower_bits':
   "\<lbrakk> len = LENGTH('a); is_aligned (x :: 'a :: len word) n;
      \<forall>n' \<ge> n. n' < len \<longrightarrow> \<not> bit p n' \<rbrakk>
    \<Longrightarrow> x + p AND NOT(mask n) = x"
   using add_mask_lower_bits by auto
 
 lemma leq_mask_shift:
   "(x :: 'a :: len word) \<le> mask (low_bits + high_bits) \<Longrightarrow> (x >> low_bits) \<le> mask high_bits"
   by (simp add: le_mask_iff shiftr_shiftr ac_simps)
 
 lemma ucast_ucast_eq_mask_shift:
   "(x :: 'a :: len word) \<le> mask (low_bits + LENGTH('b))
    \<Longrightarrow> ucast((ucast (x >> low_bits)) :: 'b :: len word) = x >> low_bits"
   by (meson and_mask_eq_iff_le_mask eq_ucast_ucast_eq not_le_imp_less shiftr_less_t2n'
             ucast_ucast_len)
 
 lemma const_le_unat:
   "\<lbrakk> b < 2 ^ LENGTH('a); of_nat b \<le> a \<rbrakk> \<Longrightarrow> b \<le> unat (a :: 'a :: len word)"
   by (simp add: word_le_nat_alt unsigned_of_nat take_bit_nat_eq_self)
 
 lemma upt_enum_offset_trivial:
   "\<lbrakk> x < 2 ^ LENGTH('a) - 1 ; n \<le> unat x \<rbrakk>
    \<Longrightarrow> ([(0 :: 'a :: len word) .e. x] ! n) = of_nat n"
   apply (induct x arbitrary: n)
     apply simp
   by (simp add: upto_enum_word_nth)
 
 lemma word_le_mask_out_plus_2sz:
   "x \<le> (x AND NOT(mask sz)) + 2 ^ sz - 1"
   for x :: \<open>'a::len word\<close>
   by (metis add_diff_eq word_neg_and_le)
 
 lemma ucast_add:
   "ucast (a + (b :: 'a :: len word)) = ucast a + (ucast b :: ('a signed word))"
   by transfer (simp add: take_bit_add)
 
 lemma ucast_minus:
   "ucast (a - (b :: 'a :: len word)) = ucast a - (ucast b :: ('a signed word))"
   apply (insert ucast_add[where a=a and b="-b"])
   apply (metis (no_types, opaque_lifting) add_diff_eq diff_add_cancel ucast_add)
   done
 
 lemma scast_ucast_add_one [simp]:
   "scast (ucast (x :: 'a::len word) + (1 :: 'a signed word)) = x + 1"
   apply (subst ucast_1[symmetric])
   apply (subst ucast_add[symmetric])
   apply clarsimp
   done
 
 lemma word_and_le_plus_one:
   "a > 0 \<Longrightarrow> (x :: 'a :: len word) AND (a - 1) < a"
   by (simp add: gt0_iff_gem1 word_and_less')
 
 lemma unat_of_ucast_then_shift_eq_unat_of_shift[simp]:
   "LENGTH('b) \<ge> LENGTH('a)
    \<Longrightarrow> unat ((ucast (x :: 'a :: len word) :: 'b :: len word) >> n) = unat (x >> n)"
   by (simp add: shiftr_div_2n' unat_ucast_up_simp)
 
 lemma unat_of_ucast_then_mask_eq_unat_of_mask[simp]:
   "LENGTH('b) \<ge> LENGTH('a)
    \<Longrightarrow> unat ((ucast (x :: 'a :: len word) :: 'b :: len word) AND mask m) = unat (x AND mask m)"
   by (metis ucast_and_mask unat_ucast_up_simp)
 
 lemma shiftr_less_t2n3:
   "\<lbrakk> (2 :: 'a word) ^ (n + m) = 0; m < LENGTH('a) \<rbrakk>
    \<Longrightarrow> (x :: 'a :: len word) >> n < 2 ^ m"
   by (fastforce intro: shiftr_less_t2n' simp: mask_eq_decr_exp power_overflow)
 
 lemma unat_shiftr_le_bound:
   "\<lbrakk> 2 ^ (LENGTH('a :: len) - n) - 1 \<le> bnd; 0 < n \<rbrakk>
    \<Longrightarrow> unat ((x :: 'a word) >> n) \<le> bnd"
   apply transfer
   apply (simp add: take_bit_drop_bit)
   apply (simp add: drop_bit_take_bit)
   apply (rule order_trans)
    defer
    apply assumption
   apply (simp add: nat_le_iff of_nat_diff)
   done
 
 lemma shiftr_eqD:
   "\<lbrakk> x >> n = y >> n; is_aligned x n; is_aligned y n \<rbrakk>
    \<Longrightarrow> x = y"
   by (metis is_aligned_shiftr_shiftl)
 
 lemma word_shiftr_shiftl_shiftr_eq_shiftr:
   "a \<ge> b \<Longrightarrow> (x :: 'a :: len word) >> a << b >> b = x >> a"
   apply (rule bit_word_eqI)
   apply (auto simp add: bit_simps dest: bit_imp_le_length)
   done
 
 lemma of_int_uint_ucast:
    "of_int (uint (x :: 'a::len word)) = (ucast x :: 'b::len word)"
   by (fact Word.of_int_uint)
 
 lemma mod_mask_drop:
   "\<lbrakk> m = 2 ^ n; 0 < m; mask n AND msk = mask n \<rbrakk>
    \<Longrightarrow> (x mod m) AND msk = x mod m"
   for x :: \<open>'a::len word\<close>
   by (simp add: word_mod_2p_is_mask word_bw_assocs)
 
 lemma mask_eq_ucast_eq:
   "\<lbrakk> x AND mask LENGTH('a) = (x :: ('c :: len word));
      LENGTH('a) \<le> LENGTH('b)\<rbrakk>
     \<Longrightarrow> ucast (ucast x :: ('a :: len word)) = (ucast x :: ('b :: len word))"
   by (metis ucast_and_mask ucast_id ucast_ucast_mask ucast_up_eq)
 
 lemma of_nat_less_t2n:
   "of_nat i < (2 :: ('a :: len) word) ^ n \<Longrightarrow> n < LENGTH('a) \<and> unat (of_nat i :: 'a word) < 2 ^ n"
   by (metis order_less_trans p2_gt_0 unat_less_power word_neq_0_conv)
 
 lemma two_power_increasing_less_1:
   "\<lbrakk> n \<le> m; m \<le> LENGTH('a) \<rbrakk> \<Longrightarrow> (2 :: 'a :: len word) ^ n - 1 \<le> 2 ^ m - 1"
   by (metis diff_diff_cancel le_m1_iff_lt less_imp_diff_less p2_gt_0 two_power_increasing
             word_1_le_power word_le_minus_mono_left word_less_sub_1)
 
 lemma word_sub_mono4:
   "\<lbrakk> y + x \<le> z + x; y \<le> y + x; z \<le> z + x \<rbrakk> \<Longrightarrow> y \<le> z" for y :: "'a :: len word"
   by (simp add: word_add_le_iff2)
 
 lemma eq_or_less_helperD:
   "\<lbrakk> n = unat (2 ^ m - 1 :: 'a :: len word) \<or> n < unat (2 ^ m - 1 :: 'a word); m < LENGTH('a) \<rbrakk>
    \<Longrightarrow> n < 2 ^ m"
   by (meson le_less_trans nat_less_le unat_less_power word_power_less_1)
 
 lemma mask_sub:
   "n \<le> m \<Longrightarrow> mask m - mask n = mask m AND NOT(mask n :: 'a::len word)"
   by (metis (full_types) and_mask_eq_iff_shiftr_0 mask_out_sub_mask shiftr_mask_le word_bw_comms(1))
 
 lemma neg_mask_diff_bound:
   "sz'\<le> sz \<Longrightarrow> (ptr AND NOT(mask sz')) - (ptr AND NOT(mask sz)) \<le> 2 ^ sz - 2 ^ sz'"
   (is "_ \<Longrightarrow> ?lhs \<le> ?rhs")
   for ptr :: \<open>'a::len word\<close>
 proof -
   assume lt: "sz' \<le> sz"
   hence "?lhs = ptr AND (mask sz AND NOT(mask sz'))"
     by (metis add_diff_cancel_left' multiple_mask_trivia)
   also have "\<dots> \<le> ?rhs" using lt
     by (metis (mono_tags) add_diff_eq diff_eq_eq eq_iff mask_2pm1 mask_sub word_and_le')
   finally show ?thesis by simp
 qed
 
 lemma mask_out_eq_0:
   "\<lbrakk> idx < 2 ^ sz; sz < LENGTH('a) \<rbrakk> \<Longrightarrow> (of_nat idx :: 'a :: len word) AND NOT(mask sz) = 0"
   by (simp add: of_nat_power less_mask_eq mask_eq_0_eq_x)
 
 lemma is_aligned_neg_mask_eq':
   "is_aligned ptr sz = (ptr AND NOT(mask sz) = ptr)"
   using is_aligned_mask mask_eq_0_eq_x by blast
 
 lemma neg_mask_mask_unat:
   "sz < LENGTH('a)
    \<Longrightarrow> unat ((ptr :: 'a :: len word) AND NOT(mask sz)) + unat (ptr AND mask sz) = unat ptr"
   by (metis AND_NOT_mask_plus_AND_mask_eq unat_plus_simple word_and_le2)
 
 lemma unat_pow_le_intro:
   "LENGTH('a) \<le> n \<Longrightarrow> unat (x :: 'a :: len word) < 2 ^ n"
   by (metis lt2p_lem not_le of_nat_le_iff of_nat_numeral semiring_1_class.of_nat_power uint_nat)
 
 lemma unat_shiftl_less_t2n:
-  "\<lbrakk> unat (x :: 'a :: len word) < 2 ^ (m - n); m < LENGTH('a) \<rbrakk> \<Longrightarrow> unat (x << n) < 2 ^ m"
-  by (metis More_Word.of_nat_power nat_mult_power_less_eq numeral_2_eq_2 of_nat_push_bit push_bit_eq_mult unat_less_power unat_of_nat_len unsigned_less word_eq_unatI zero_less_Suc)
+  \<open>unat (x << n) < 2 ^ m\<close>
+  if \<open>unat (x :: 'a :: len word) < 2 ^ (m - n)\<close> \<open>m < LENGTH('a)\<close>
+proof (cases \<open>n \<le> m\<close>)
+  case False
+  with that show ?thesis
+    apply (transfer fixing: m n)
+    apply (simp add: not_le take_bit_push_bit)
+    apply (metis diff_le_self order_le_less_trans push_bit_of_0 take_bit_0 take_bit_int_eq_self 
+      take_bit_int_less_exp take_bit_nonnegative take_bit_tightened)    
+    done
+next
+  case True
+  moreover define q r where \<open>q = m - n\<close> and \<open>r = LENGTH('a) - n - q\<close>
+  ultimately have \<open>m - n = q\<close> \<open>m = n + q\<close> \<open>LENGTH('a) = r + q + n\<close>
+    using that by simp_all
+  with that show ?thesis
+    apply (transfer fixing: m n q r)
+    apply (simp add: not_le take_bit_push_bit)
+    apply (simp add: push_bit_eq_mult power_add)
+    using take_bit_tightened_less_eq_int [of \<open>r + q\<close> \<open>r + q + n\<close>]
+    apply (rule le_less_trans)
+     apply simp_all
+    done
+qed
 
 lemma unat_is_aligned_add:
   "\<lbrakk> is_aligned p n; unat d < 2 ^ n \<rbrakk>
    \<Longrightarrow> unat (p + d AND mask n) = unat d \<and> unat (p + d AND NOT(mask n)) = unat p"
   by (metis add.right_neutral and_mask_eq_iff_le_mask and_not_mask le_mask_iff mask_add_aligned
             mask_out_add_aligned mult_zero_right shiftl_t2n shiftr_le_0)
 
 lemma unat_shiftr_shiftl_mask_zero:
   "\<lbrakk> c + a \<ge> LENGTH('a) + b ; c < LENGTH('a) \<rbrakk>
    \<Longrightarrow> unat (((q :: 'a :: len word) >> a << b) AND NOT(mask c)) = 0"
   by (fastforce intro: unat_is_aligned_add[where p=0 and n=c, simplified, THEN conjunct2]
                        unat_shiftl_less_t2n unat_shiftr_less_t2n unat_pow_le_intro)
 
 lemmas of_nat_ucast = ucast_of_nat[symmetric]
 
 lemma shift_then_mask_eq_shift_low_bits:
   "x \<le> mask (low_bits + high_bits) \<Longrightarrow> (x >> low_bits) AND mask high_bits = x >> low_bits"
   for x :: \<open>'a::len word\<close>
   by (simp add: leq_mask_shift le_mask_imp_and_mask)
 
 lemma leq_low_bits_iff_zero:
   "\<lbrakk> x \<le> mask (low bits + high bits); x >> low_bits = 0 \<rbrakk> \<Longrightarrow> (x AND mask low_bits = 0) = (x = 0)"
   for x :: \<open>'a::len word\<close>
   using and_mask_eq_iff_shiftr_0 by force
 
 lemma unat_less_iff:
   "\<lbrakk> unat (a :: 'a :: len word) = b; c < 2 ^ LENGTH('a) \<rbrakk> \<Longrightarrow> (a < of_nat c) = (b < c)"
   using unat_ucast_less_no_overflow_simp by blast
 
 lemma is_aligned_no_overflow3:
  "\<lbrakk> is_aligned (a :: 'a :: len word) n; n < LENGTH('a); b < 2 ^ n; c \<le> 2 ^ n; b < c \<rbrakk>
   \<Longrightarrow> a + b \<le> a + (c - 1)"
   by (meson is_aligned_no_wrap' le_m1_iff_lt not_le word_less_sub_1 word_plus_mono_right)
 
 lemma mask_add_aligned_right:
   "is_aligned p n \<Longrightarrow> (q + p) AND mask n = q AND mask n"
   by (simp add: mask_add_aligned add.commute)
 
 lemma leq_high_bits_shiftr_low_bits_leq_bits_mask:
   "x \<le> mask high_bits \<Longrightarrow> (x :: 'a :: len word) << low_bits \<le> mask (low_bits + high_bits)"
   by (metis le_mask_shiftl_le_mask)
 
 lemma word_two_power_neg_ineq:
   "2 ^ m \<noteq> (0 :: 'a word) \<Longrightarrow> 2 ^ n \<le> - (2 ^ m :: 'a :: len word)"
   apply (cases "n < LENGTH('a)"; simp add: power_overflow)
   apply (cases "m < LENGTH('a)"; simp add: power_overflow)
   apply (simp add: word_le_nat_alt unat_minus word_size)
   apply (cases "LENGTH('a)"; simp)
   apply (simp add: less_Suc_eq_le)
   apply (drule power_increasing[where a=2 and n=n] power_increasing[where a=2 and n=m], simp)+
   apply (drule(1) add_le_mono)
   apply simp
   done
 
 lemma unat_shiftl_absorb:
   "\<lbrakk> x \<le> 2 ^ p; p + k < LENGTH('a) \<rbrakk> \<Longrightarrow> unat (x :: 'a :: len word) * 2 ^ k = unat (x * 2 ^ k)"
   by (smt add_diff_cancel_right' add_lessD1 le_add2 le_less_trans mult.commute nat_le_power_trans
           unat_lt2p unat_mult_lem unat_power_lower word_le_nat_alt)
 
 lemma word_plus_mono_right_split:
   "\<lbrakk> unat ((x :: 'a :: len word) AND mask sz) + unat z < 2 ^ sz; sz < LENGTH('a) \<rbrakk>
    \<Longrightarrow> x \<le> x + z"
   apply (subgoal_tac "(x AND NOT(mask sz)) + (x AND mask sz) \<le> (x AND NOT(mask sz)) + ((x AND mask sz) + z)")
    apply (simp add:word_plus_and_or_coroll2 field_simps)
   apply (rule word_plus_mono_right)
    apply (simp add: less_le_trans no_olen_add_nat)
   using of_nat_power is_aligned_no_wrap' by force
 
 lemma mul_not_mask_eq_neg_shiftl:
   "NOT(mask n :: 'a::len word) = -1 << n"
   by (simp add: NOT_mask shiftl_t2n)
 
 lemma shiftr_mul_not_mask_eq_and_not_mask:
   "(x >> n) * NOT(mask n) = - (x AND NOT(mask n))"
   for x :: \<open>'a::len word\<close>
   by (metis NOT_mask and_not_mask mult_minus_left semiring_normalization_rules(7) shiftl_t2n)
 
 lemma mask_eq_n1_shiftr:
   "n \<le> LENGTH('a) \<Longrightarrow> (mask n :: 'a :: len word) = -1 >> (LENGTH('a) - n)"
   by (metis diff_diff_cancel eq_refl mask_full shiftr_mask2)
 
 lemma is_aligned_mask_out_add_eq:
   "is_aligned p n \<Longrightarrow> (p + x) AND NOT(mask n) = p + (x AND NOT(mask n))"
   by (simp add: mask_out_sub_mask mask_add_aligned)
 
 lemmas is_aligned_mask_out_add_eq_sub
     = is_aligned_mask_out_add_eq[where x="a - b" for a b, simplified field_simps]
 
 lemma aligned_bump_down:
   "is_aligned x n \<Longrightarrow> (x - 1) AND NOT(mask n) = x - 2 ^ n"
   by (drule is_aligned_mask_out_add_eq[where x="-1"]) (simp add: NOT_mask)
 
 lemma unat_2tp_if:
   "unat (2 ^ n :: ('a :: len) word) = (if n < LENGTH ('a) then 2 ^ n else 0)"
   by (split if_split, simp_all add: power_overflow)
 
 lemma mask_of_mask:
   "mask (n::nat) AND mask (m::nat) = (mask (min m n) :: 'a::len word)"
-  by word_eqI_solve
+  by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma unat_signed_ucast_less_ucast:
   "LENGTH('a) \<le> LENGTH('b) \<Longrightarrow> unat (ucast (x :: 'a :: len word) :: 'b :: len signed word) = unat x"
   by (simp add: unat_ucast_up_simp)
 
 lemma toEnum_of_ucast:
   "LENGTH('b) \<le> LENGTH('a) \<Longrightarrow>
    (toEnum (unat (b::'b :: len word))::'a :: len word) = of_nat (unat b)"
   by (simp add: unat_pow_le_intro)
 
 lemmas unat_ucast_mask = unat_ucast_eq_unat_and_mask[where w=a for a]
 
 lemma t2n_mask_eq_if:
   "2 ^ n AND mask m = (if n < m then 2 ^ n else (0 :: 'a::len word))"
   by (rule word_eqI) (auto simp add: bit_simps)
 
 lemma unat_ucast_le:
   "unat (ucast (x :: 'a :: len word) :: 'b :: len word) \<le> unat x"
   by (simp add: ucast_nat_def word_unat_less_le)
 
 lemma ucast_le_up_down_iff:
   "\<lbrakk> LENGTH('a) \<le> LENGTH('b); (x :: 'b :: len word) \<le> ucast (- 1 :: 'a :: len word) \<rbrakk>
    \<Longrightarrow> (ucast x \<le> (y :: 'a word)) = (x \<le> ucast y)"
   using le_max_word_ucast_id ucast_le_ucast by metis
 
 lemma ucast_ucast_mask_shift:
   "a \<le> LENGTH('a) + b
    \<Longrightarrow> ucast (ucast (p AND mask a >> b) :: 'a :: len word) = p AND mask a >> b"
   by (metis add.commute le_mask_iff shiftr_mask_le ucast_ucast_eq_mask_shift word_and_le')
 
 lemma unat_ucast_mask_shift:
   "a \<le> LENGTH('a) + b
    \<Longrightarrow> unat (ucast (p AND mask a >> b) :: 'a :: len word) = unat (p AND mask a >> b)"
   by (metis linear ucast_ucast_mask_shift unat_ucast_up_simp)
 
 lemma mask_overlap_zero:
   "a \<le> b \<Longrightarrow> (p AND mask a) AND NOT(mask b) = 0"
   for p :: \<open>'a::len word\<close>
   by (metis NOT_mask_AND_mask mask_lower_twice2 max_def)
 
 lemma mask_shifl_overlap_zero:
   "a + c \<le> b \<Longrightarrow> (p AND mask a << c) AND NOT(mask b) = 0"
   for p :: \<open>'a::len word\<close>
   by (metis and_mask_0_iff_le_mask mask_mono mask_shiftl_decompose order_trans shiftl_over_and_dist word_and_le' word_and_le2)
 
 lemma mask_overlap_zero':
   "a \<ge> b \<Longrightarrow> (p AND NOT(mask a)) AND mask b = 0"
   for p :: \<open>'a::len word\<close>
   using mask_AND_NOT_mask mask_AND_less_0 by blast
 
 lemma mask_rshift_mult_eq_rshift_lshift:
   "((a :: 'a :: len word) >> b) * (1 << c) = (a >> b << c)"
   by (simp add: shiftl_t2n)
 
 lemma shift_alignment:
   "a \<ge> b \<Longrightarrow> is_aligned (p >> a << a) b"
   using is_aligned_shift is_aligned_weaken by blast
 
 lemma mask_split_sum_twice:
   "a \<ge> b \<Longrightarrow> (p AND NOT(mask a)) + ((p AND mask a) AND NOT(mask b)) + (p AND mask b) = p"
   for p :: \<open>'a::len word\<close>
   by (simp add: add.commute multiple_mask_trivia word_bw_comms(1) word_bw_lcs(1) word_plus_and_or_coroll2)
 
 lemma mask_shift_eq_mask_mask:
   "(p AND mask a >> b << b) = (p AND mask a) AND NOT(mask b)"
   for p :: \<open>'a::len word\<close>
   by (simp add: and_not_mask)
 
 lemma mask_shift_sum:
   "\<lbrakk> a \<ge> b; unat n = unat (p AND mask b) \<rbrakk>
    \<Longrightarrow> (p AND NOT(mask a)) + (p AND mask a >> b) * (1 << b) + n = (p :: 'a :: len word)"
-  apply (simp add: push_bit_of_1 flip: push_bit_eq_mult)
+  apply (simp add: shiftl_def shiftr_def flip: push_bit_eq_mult take_bit_eq_mask word_unat_eq_iff)
   apply (subst disjunctive_add)
    apply (auto simp add: bit_simps)
-  apply (smt (z3) AND_NOT_mask_plus_AND_mask_eq and.comm_neutral and.right_idem and_not_mask bit.conj_disj_distrib bit.disj_cancel_right mask_out_first_mask_some word_bw_assocs(1) word_bw_comms(1) word_bw_comms(2) word_eq_unatI)
+  apply (subst disjunctive_add)
+   apply (auto simp add: bit_simps)
+    apply (rule bit_word_eqI)
+  apply (auto simp add: bit_simps)
   done
 
 lemma is_up_compose:
   "\<lbrakk> is_up uc; is_up uc' \<rbrakk> \<Longrightarrow> is_up (uc' \<circ> uc)"
   unfolding is_up_def by (simp add: Word.target_size Word.source_size)
 
 lemma of_int_sint_scast:
   "of_int (sint (x :: 'a :: len word)) = (scast x :: 'b :: len word)"
   by (fact Word.of_int_sint)
 
 lemma scast_of_nat_to_signed [simp]:
   "scast (of_nat x :: 'a :: len word) = (of_nat x :: 'a signed word)"
   by (rule bit_word_eqI) (simp add: bit_simps)
 
 lemma scast_of_nat_signed_to_unsigned_add:
   "scast (of_nat x + of_nat y :: 'a :: len signed word) = (of_nat x + of_nat y :: 'a :: len word)"
   by (metis of_nat_add scast_of_nat)
 
 lemma scast_of_nat_unsigned_to_signed_add:
   "(scast (of_nat x + of_nat y :: 'a :: len word)) = (of_nat x + of_nat y :: 'a :: len signed word)"
   by (metis Abs_fnat_hom_add scast_of_nat_to_signed)
 
 lemma and_mask_cases:
   fixes x :: "'a :: len word"
   assumes len: "n < LENGTH('a)"
   shows "x AND mask n \<in> of_nat ` set [0 ..< 2 ^ n]"
   apply (simp flip: take_bit_eq_mask)
   apply (rule image_eqI [of _ _ \<open>unat (take_bit n x)\<close>])
   using len apply simp_all
   apply transfer
   apply simp
   done
 
 lemma sint_eq_uint_2pl:
   "\<lbrakk> (a :: 'a :: len word) < 2 ^ (LENGTH('a) - 1) \<rbrakk>
    \<Longrightarrow> sint a = uint a"
   by (simp add: not_msb_from_less sint_eq_uint word_2p_lem word_size)
 
 lemma pow_sub_less:
   "\<lbrakk> a + b \<le> LENGTH('a); unat (x :: 'a :: len word) = 2 ^ a \<rbrakk>
    \<Longrightarrow> unat (x * 2 ^ b - 1) < 2 ^ (a + b)"
   by (smt (z3) eq_or_less_helperD le_add2 le_eq_less_or_eq le_trans power_add unat_mult_lem unat_pow_le_intro unat_power_lower word_eq_unatI)
 
 lemma sle_le_2pl:
   "\<lbrakk> (b :: 'a :: len word) < 2 ^ (LENGTH('a) - 1); a \<le> b \<rbrakk> \<Longrightarrow> a <=s b"
   by (simp add: not_msb_from_less word_sle_msb_le)
 
 lemma sless_less_2pl:
   "\<lbrakk> (b :: 'a :: len word) < 2 ^ (LENGTH('a) - 1); a < b \<rbrakk> \<Longrightarrow> a <s b"
   using not_msb_from_less word_sless_msb_less by blast
 
 lemma and_mask2:
   "w << n >> n = w AND mask (size w - n)"
   for w :: \<open>'a::len word\<close>
-  by (cases "n \<le> size w"; clarsimp simp: word_and_le2 and_mask shiftl_zero_size)
+  by (rule bit_word_eqI) (auto simp add: bit_simps word_size)
 
 lemma aligned_sub_aligned_simple:
   "\<lbrakk> is_aligned a n; is_aligned b n \<rbrakk> \<Longrightarrow> is_aligned (a - b) n"
   by (simp add: aligned_sub_aligned)
 
 lemma minus_one_shift:
   "- (1 << n) = (-1 << n :: 'a::len word)"
-  by (simp flip: mul_not_mask_eq_neg_shiftl minus_exp_eq_not_mask add: push_bit_of_1)
+  by (simp add: shiftl_def minus_exp_eq_not_mask push_bit_minus_one_eq_not_mask)
 
 lemma ucast_eq_mask:
   "(UCAST('a::len \<rightarrow> 'b::len) x = UCAST('a \<rightarrow> 'b) y) =
    (x AND mask LENGTH('b) = y AND mask LENGTH('b))"
   by transfer (simp flip: take_bit_eq_mask add: ac_simps)
 
 context
   fixes w :: "'a::len word"
 begin
 
 private lemma sbintrunc_uint_ucast:
   assumes "Suc n = LENGTH('b::len)"
   shows "signed_take_bit n (uint (ucast w :: 'b word)) = signed_take_bit n (uint w)"
   by (rule bit_eqI) (use assms in \<open>simp add: bit_simps\<close>)
 
 private lemma test_bit_sbintrunc:
   assumes "i < LENGTH('a)"
   shows "bit (word_of_int (signed_take_bit n (uint w)) :: 'a word) i
            = (if n < i then bit w n else bit w i)"
   using assms by (simp add: bit_simps)
 
 private lemma test_bit_sbintrunc_ucast:
   assumes len_a: "i < LENGTH('a)"
   shows "bit (word_of_int (signed_take_bit (LENGTH('b) - 1) (uint (ucast w :: 'b word))) :: 'a word) i
           = (if LENGTH('b::len) \<le> i then bit w (LENGTH('b) - 1) else bit w i)"
   using len_a by (auto simp add: sbintrunc_uint_ucast bit_simps)
 
 lemma scast_ucast_high_bits:
   \<open>scast (ucast w :: 'b::len word) = w
      \<longleftrightarrow> (\<forall> i \<in> {LENGTH('b) ..< size w}. bit w i = bit w (LENGTH('b) - 1))\<close>
 proof (cases \<open>LENGTH('a) \<le> LENGTH('b)\<close>)
   case True
   moreover define m where \<open>m = LENGTH('b) - LENGTH('a)\<close>
   ultimately have \<open>LENGTH('b) = m + LENGTH('a)\<close>
     by simp
   then show ?thesis
     apply (simp_all add: signed_ucast_eq word_size)
     apply (rule bit_word_eqI)
     apply (simp add: bit_signed_take_bit_iff)
     done
 next
   case False
   define q where \<open>q = LENGTH('b) - 1\<close>
   then have \<open>LENGTH('b) = Suc q\<close>
     by simp
   moreover define m where \<open>m = Suc LENGTH('a) - LENGTH('b)\<close>
   with False \<open>LENGTH('b) = Suc q\<close> have \<open>LENGTH('a) = m + q\<close>
     by (simp add: not_le)
   ultimately show ?thesis
     apply (simp_all add: signed_ucast_eq word_size)
     apply (transfer fixing: m q)
     apply (simp add: signed_take_bit_take_bit)
     apply rule
     apply (subst bit_eq_iff)
     apply (simp add: bit_take_bit_iff bit_signed_take_bit_iff min_def)
     apply (auto simp add: Suc_le_eq)
     using less_imp_le_nat apply blast
     using less_imp_le_nat apply blast
     done
 qed
 
 lemma scast_ucast_mask_compare:
   "scast (ucast w :: 'b::len word) = w
    \<longleftrightarrow> (w \<le> mask (LENGTH('b) - 1) \<or> NOT(mask (LENGTH('b) - 1)) \<le> w)"
   apply (clarsimp simp: le_mask_high_bits neg_mask_le_high_bits scast_ucast_high_bits word_size)
   apply (rule iffI; clarsimp)
    apply (rename_tac i j; case_tac "i = LENGTH('b) - 1"; case_tac "j = LENGTH('b) - 1")
   by auto
 
 lemma ucast_less_shiftl_helper':
   "\<lbrakk> LENGTH('b) + (a::nat) < LENGTH('a); 2 ^ (LENGTH('b) + a) \<le> n\<rbrakk>
    \<Longrightarrow> (ucast (x :: 'b::len word) << a) < (n :: 'a::len word)"
   apply (erule order_less_le_trans[rotated])
   using ucast_less[where x=x and 'a='a]
   apply (simp only: shiftl_t2n field_simps)
   apply (rule word_less_power_trans2; simp)
   done
 
 end
 
 lemma ucast_ucast_mask2:
   "is_down (UCAST ('a \<rightarrow> 'b)) \<Longrightarrow>
    UCAST ('b::len \<rightarrow> 'c::len) (UCAST ('a::len \<rightarrow> 'b::len) x) = UCAST ('a \<rightarrow> 'c) (x AND mask LENGTH('b))"
   apply (simp flip: take_bit_eq_mask)
   apply transfer
   apply simp
   done
 
 lemma ucast_NOT:
   "ucast (NOT x) = NOT(ucast x) AND mask (LENGTH('a))" for x::"'a::len word"
-  by word_eqI
+  by (rule bit_word_eqI) (auto simp add: bit_simps)
 
 lemma ucast_NOT_down:
   "is_down UCAST('a::len \<rightarrow> 'b::len) \<Longrightarrow> UCAST('a \<rightarrow> 'b) (NOT x) = NOT(UCAST('a \<rightarrow> 'b) x)"
-  by word_eqI
+  by (rule bit_word_eqI) (auto simp add: bit_simps is_down.rep_eq)
 
 lemma upto_enum_step_shift:
   "\<lbrakk> is_aligned p n \<rbrakk> \<Longrightarrow>
   ([p , p + 2 ^ m .e. p + 2 ^ n - 1])
       = map ((+) p) [0, 2 ^ m .e. 2 ^ n - 1]"
   apply (erule is_aligned_get_word_bits)
    prefer 2
    apply (simp add: map_idI)
   apply (clarsimp simp: upto_enum_step_def)
   apply (frule is_aligned_no_overflow)
   apply (simp add: linorder_not_le [symmetric])
   done
 
 lemma upto_enum_step_shift_red:
   "\<lbrakk> is_aligned p sz; sz < LENGTH('a); us \<le> sz \<rbrakk>
      \<Longrightarrow> [p :: 'a :: len word, p + 2 ^ us .e. p + 2 ^ sz - 1]
           = map (\<lambda>x. p + of_nat x * 2 ^ us) [0 ..< 2 ^ (sz - us)]"
   apply (subst upto_enum_step_shift, assumption)
   apply (simp add: upto_enum_step_red)
   done
 
 lemma upto_enum_step_subset:
   "set [x, y .e. z] \<subseteq> {x .. z}"
   apply (clarsimp simp: upto_enum_step_def linorder_not_less)
   apply (drule div_to_mult_word_lt)
   apply (rule conjI)
    apply (erule word_random[rotated])
    apply simp
   apply (rule order_trans)
    apply (erule word_plus_mono_right)
    apply simp
   apply simp
   done
 
 lemma ucast_distrib:
   fixes M :: "'a::len word \<Rightarrow> 'a::len word \<Rightarrow> 'a::len word"
   fixes M' :: "'b::len word \<Rightarrow> 'b::len word \<Rightarrow> 'b::len word"
   fixes L :: "int \<Rightarrow> int \<Rightarrow> int"
   assumes lift_M: "\<And>x y. uint (M x y) = L (uint x) (uint y)  mod 2 ^ LENGTH('a)"
   assumes lift_M': "\<And>x y. uint (M' x y) = L (uint x) (uint y)  mod 2 ^ LENGTH('b)"
   assumes distrib: "\<And>x y. (L (x mod (2 ^ LENGTH('b))) (y mod (2 ^ LENGTH('b)))) mod (2 ^ LENGTH('b))
                                = (L x y) mod (2 ^ LENGTH('b))"
   assumes is_down: "is_down (ucast :: 'a word \<Rightarrow> 'b word)"
   shows "ucast (M a b) = M' (ucast a) (ucast b)"
   apply (simp only: ucast_eq)
   apply (subst lift_M)
   apply (subst of_int_uint [symmetric], subst lift_M')
   apply (metis local.distrib local.is_down take_bit_eq_mod ucast_down_wi uint_word_of_int_eq word_of_int_uint)
   done
 
 lemma ucast_down_add:
     "is_down (ucast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  ucast ((a :: 'a::len word) + b) = (ucast a + ucast b :: 'b::len word)"
   by (rule ucast_distrib [where L="(+)"], (clarsimp simp: uint_word_ariths)+, presburger, simp)
 
 lemma ucast_down_minus:
     "is_down (ucast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  ucast ((a :: 'a::len word) - b) = (ucast a - ucast b :: 'b::len word)"
   apply (rule ucast_distrib [where L="(-)"], (clarsimp simp: uint_word_ariths)+)
   apply (metis mod_diff_left_eq mod_diff_right_eq)
   apply simp
   done
 
 lemma ucast_down_mult:
     "is_down (ucast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  ucast ((a :: 'a::len word) * b) = (ucast a * ucast b :: 'b::len word)"
   apply (rule ucast_distrib [where L="(*)"], (clarsimp simp: uint_word_ariths)+)
   apply (metis mod_mult_eq)
   apply simp
   done
 
 lemma scast_distrib:
   fixes M :: "'a::len word \<Rightarrow> 'a::len word \<Rightarrow> 'a::len word"
   fixes M' :: "'b::len word \<Rightarrow> 'b::len word \<Rightarrow> 'b::len word"
   fixes L :: "int \<Rightarrow> int \<Rightarrow> int"
   assumes lift_M: "\<And>x y. uint (M x y) = L (uint x) (uint y)  mod 2 ^ LENGTH('a)"
   assumes lift_M': "\<And>x y. uint (M' x y) = L (uint x) (uint y)  mod 2 ^ LENGTH('b)"
   assumes distrib: "\<And>x y. (L (x mod (2 ^ LENGTH('b))) (y mod (2 ^ LENGTH('b)))) mod (2 ^ LENGTH('b))
                                = (L x y) mod (2 ^ LENGTH('b))"
   assumes is_down: "is_down (scast :: 'a word \<Rightarrow> 'b word)"
   shows "scast (M a b) = M' (scast a) (scast b)"
   apply (subst (1 2 3) down_cast_same [symmetric])
    apply (insert is_down)
    apply (clarsimp simp: is_down_def target_size source_size is_down)
   apply (rule ucast_distrib [where L=L, OF lift_M lift_M' distrib])
   apply (insert is_down)
   apply (clarsimp simp: is_down_def target_size source_size is_down)
   done
 
 lemma scast_down_add:
     "is_down (scast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  scast ((a :: 'a::len word) + b) = (scast a + scast b :: 'b::len word)"
   by (rule scast_distrib [where L="(+)"], (clarsimp simp: uint_word_ariths)+, presburger, simp)
 
 lemma scast_down_minus:
     "is_down (scast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  scast ((a :: 'a::len word) - b) = (scast a - scast b :: 'b::len word)"
   apply (rule scast_distrib [where L="(-)"], (clarsimp simp: uint_word_ariths)+)
   apply (metis mod_diff_left_eq mod_diff_right_eq)
   apply simp
   done
 
 lemma scast_down_mult:
     "is_down (scast:: 'a word \<Rightarrow> 'b word) \<Longrightarrow>  scast ((a :: 'a::len word) * b) = (scast a * scast b :: 'b::len word)"
   apply (rule scast_distrib [where L="(*)"], (clarsimp simp: uint_word_ariths)+)
   apply (metis mod_mult_eq)
   apply simp
   done
 
 lemma scast_ucast_1:
   "\<lbrakk> is_down (ucast :: 'a word \<Rightarrow> 'b word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
          (scast (ucast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = ucast a"
   by (metis down_cast_same ucast_eq ucast_down_wi)
 
 lemma scast_ucast_3:
   "\<lbrakk> is_down (ucast :: 'a word \<Rightarrow> 'c word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
          (scast (ucast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = ucast a"
   by (metis down_cast_same ucast_eq ucast_down_wi)
 
 lemma scast_ucast_4:
   "\<lbrakk> is_up (ucast :: 'a word \<Rightarrow> 'b word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
          (scast (ucast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = ucast a"
   by (metis down_cast_same ucast_eq ucast_down_wi)
 
 lemma scast_scast_b:
   "\<lbrakk> is_up (scast :: 'a word \<Rightarrow> 'b word) \<rbrakk> \<Longrightarrow>
      (scast (scast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = scast a"
   by (metis scast_eq sint_up_scast)
 
 lemma ucast_scast_1:
   "\<lbrakk> is_down (scast :: 'a word \<Rightarrow> 'b word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
             (ucast (scast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = scast a"
   by (metis scast_eq ucast_down_wi)
 
 lemma ucast_scast_3:
   "\<lbrakk> is_down (scast :: 'a word \<Rightarrow> 'c word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
      (ucast (scast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = scast a"
   by (metis scast_eq ucast_down_wi)
 
 lemma ucast_scast_4:
   "\<lbrakk> is_up (scast :: 'a word \<Rightarrow> 'b word); is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
      (ucast (scast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = scast a"
   by (metis down_cast_same scast_eq sint_up_scast)
 
 lemma ucast_ucast_a:
   "\<lbrakk> is_down (ucast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
         (ucast (ucast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = ucast a"
   by (metis down_cast_same ucast_eq ucast_down_wi)
 
 lemma ucast_ucast_b:
   "\<lbrakk> is_up (ucast :: 'a word \<Rightarrow> 'b word) \<rbrakk> \<Longrightarrow>
      (ucast (ucast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = ucast a"
   by (metis ucast_up_ucast)
 
 lemma scast_scast_a:
   "\<lbrakk> is_down (scast :: 'b word \<Rightarrow> 'c word) \<rbrakk> \<Longrightarrow>
             (scast (scast (a :: 'a::len word) :: 'b::len word) :: 'c::len word) = scast a"
   apply (simp only: scast_eq)
   apply (metis down_cast_same is_up_down scast_eq ucast_down_wi)
   done
 
 lemma scast_down_wi [OF refl]:
   "uc = scast \<Longrightarrow> is_down uc \<Longrightarrow> uc (word_of_int x) = word_of_int x"
   by (metis down_cast_same is_up_down ucast_down_wi)
 
 lemmas cast_simps =
   is_down is_up
   scast_down_add scast_down_minus scast_down_mult
   ucast_down_add ucast_down_minus ucast_down_mult
   scast_ucast_1 scast_ucast_3 scast_ucast_4
   ucast_scast_1 ucast_scast_3 ucast_scast_4
   ucast_ucast_a ucast_ucast_b
   scast_scast_a scast_scast_b
   ucast_down_wi scast_down_wi
   ucast_of_nat scast_of_nat
   uint_up_ucast sint_up_scast
   up_scast_surj up_ucast_surj
 
 lemma sdiv_word_max:
     "(sint (a :: ('a::len) word) sdiv sint (b :: ('a::len) word) < (2 ^ (size a - 1))) =
           ((a \<noteq> - (2 ^ (size a - 1)) \<or> (b \<noteq> -1)))"
     (is "?lhs = (\<not> ?a_int_min \<or> \<not> ?b_minus1)")
 proof (rule classical)
   assume not_thesis: "\<not> ?thesis"
 
   have not_zero: "b \<noteq> 0"
     using not_thesis
     by (clarsimp)
 
   let ?range = \<open>{- (2 ^ (size a - 1))..<2 ^ (size a - 1)} :: int set\<close>
 
   have result_range: "sint a sdiv sint b \<in> ?range \<union> {2 ^ (size a - 1)}"
     using sdiv_word_min [of a b] sdiv_word_max [of a b] by auto
 
   have result_range_overflow: "(sint a sdiv sint b = 2 ^ (size a - 1)) = (?a_int_min \<and> ?b_minus1)"
     apply (rule iffI [rotated])
      apply (clarsimp simp: signed_divide_int_def sgn_if word_size sint_int_min)
     apply (rule classical)
     apply (case_tac "?a_int_min")
      apply (clarsimp simp: word_size sint_int_min)
      apply (metis diff_0_right
               int_sdiv_negated_is_minus1 minus_diff_eq minus_int_code(2)
               power_eq_0_iff sint_minus1 zero_neq_numeral)
     apply (subgoal_tac "abs (sint a) < 2 ^ (size a - 1)")
      apply (insert sdiv_int_range [where a="sint a" and b="sint b"])[1]
      apply (clarsimp simp: word_size)
     apply (insert sdiv_int_range [where a="sint a" and b="sint b"])[1]
     apply auto
     apply (cases \<open>size a\<close>)
      apply simp_all
     apply (smt (z3) One_nat_def diff_Suc_1 signed_word_eqI sint_int_min sint_range_size wsst_TYs(3))
     done
 
   have result_range_simple: "(sint a sdiv sint b \<in> ?range) \<Longrightarrow> ?thesis"
     apply (insert sdiv_int_range [where a="sint a" and b="sint b"])
     apply (clarsimp simp: word_size sint_int_min)
     done
 
   show ?thesis
     apply (rule UnE [OF result_range result_range_simple])
      apply simp
     apply (clarsimp simp: word_size)
     using result_range_overflow
     apply (clarsimp simp: word_size)
     done
 qed
 
 lemmas sdiv_word_min' = sdiv_word_min [simplified word_size, simplified]
 lemmas sdiv_word_max' = sdiv_word_max [simplified word_size, simplified]
 
 lemma signed_arith_ineq_checks_to_eq:
   "((- (2 ^ (size a - 1)) \<le> (sint a + sint b)) \<and> (sint a + sint b \<le> (2 ^ (size a - 1) - 1)))
     = (sint a + sint b = sint (a + b ))"
   "((- (2 ^ (size a - 1)) \<le> (sint a - sint b)) \<and> (sint a - sint b \<le> (2 ^ (size a - 1) - 1)))
     = (sint a - sint b = sint (a - b))"
   "((- (2 ^ (size a - 1)) \<le> (- sint a)) \<and> (- sint a) \<le> (2 ^ (size a - 1) - 1))
     = ((- sint a) = sint (- a))"
   "((- (2 ^ (size a - 1)) \<le> (sint a * sint b)) \<and> (sint a * sint b \<le> (2 ^ (size a - 1) - 1)))
     = (sint a * sint b = sint (a * b))"
   "((- (2 ^ (size a - 1)) \<le> (sint a sdiv sint b)) \<and> (sint a sdiv sint b \<le> (2 ^ (size a - 1) - 1)))
     = (sint a sdiv sint b = sint (a sdiv b))"
   "((- (2 ^ (size a - 1)) \<le> (sint a smod sint b)) \<and> (sint a smod sint b \<le> (2 ^ (size a - 1) - 1)))
     = (sint a smod sint b = sint (a smod b))"
   by (auto simp: sint_word_ariths word_size signed_div_arith signed_mod_arith signed_take_bit_int_eq_self_iff intro: sym dest: sym)
 
 lemma signed_arith_sint:
   "((- (2 ^ (size a - 1)) \<le> (sint a + sint b)) \<and> (sint a + sint b \<le> (2 ^ (size a - 1) - 1)))
     \<Longrightarrow> sint (a + b) = (sint a + sint b)"
   "((- (2 ^ (size a - 1)) \<le> (sint a - sint b)) \<and> (sint a - sint b \<le> (2 ^ (size a - 1) - 1)))
     \<Longrightarrow> sint (a - b) = (sint a - sint b)"
   "((- (2 ^ (size a - 1)) \<le> (- sint a)) \<and> (- sint a) \<le> (2 ^ (size a - 1) - 1))
     \<Longrightarrow> sint (- a) = (- sint a)"
   "((- (2 ^ (size a - 1)) \<le> (sint a * sint b)) \<and> (sint a * sint b \<le> (2 ^ (size a - 1) - 1)))
     \<Longrightarrow> sint (a * b) = (sint a * sint b)"
   "((- (2 ^ (size a - 1)) \<le> (sint a sdiv sint b)) \<and> (sint a sdiv sint b \<le> (2 ^ (size a - 1) - 1)))
     \<Longrightarrow> sint (a sdiv b) = (sint a sdiv sint b)"
   "((- (2 ^ (size a - 1)) \<le> (sint a smod sint b)) \<and> (sint a smod sint b \<le> (2 ^ (size a - 1) - 1)))
     \<Longrightarrow> sint (a smod b) = (sint a smod sint b)"
   by (subst (asm) signed_arith_ineq_checks_to_eq; simp)+
 
+lemma nasty_split_lt:
+  \<open>x * 2 ^ n + (2 ^ n - 1) \<le> 2 ^ m - 1\<close>
+    if \<open>x < 2 ^ (m - n)\<close> \<open>n \<le> m\<close> \<open>m < LENGTH('a::len)\<close>
+    for x :: \<open>'a::len word\<close>
+proof -
+  define q where \<open>q = m - n\<close>
+  with \<open>n \<le> m\<close> have \<open>m = q + n\<close>
+    by simp
+  with \<open>x < 2 ^ (m - n)\<close> have *: \<open>i < q\<close> if \<open>bit x i\<close> for i
+    using that by simp (metis bit_take_bit_iff take_bit_word_eq_self_iff)
+  from \<open>m = q + n\<close> have \<open>push_bit n x OR mask n \<le> mask m\<close>
+    by (auto simp add: le_mask_high_bits word_size bit_simps dest!: *)
+  then have \<open>push_bit n x + mask n \<le> mask m\<close>
+    by (simp add: disjunctive_add bit_simps)
+  then show ?thesis
+    by (simp add: mask_eq_exp_minus_1 push_bit_eq_mult)
+qed
+
+lemma nasty_split_less:
+  "\<lbrakk>m \<le> n; n \<le> nm; nm < LENGTH('a::len); x < 2 ^ (nm - n)\<rbrakk>
+   \<Longrightarrow> (x :: 'a word) * 2 ^ n + (2 ^ m - 1) < 2 ^ nm"
+  apply (simp only: word_less_sub_le[symmetric])
+  apply (rule order_trans [OF _ nasty_split_lt])
+     apply (rule word_plus_mono_right)
+      apply (rule word_sub_mono)
+         apply (simp add: word_le_nat_alt)
+        apply simp
+       apply (simp add: word_sub_1_le[OF power_not_zero])
+      apply (simp add: word_sub_1_le[OF power_not_zero])
+     apply (rule is_aligned_no_wrap')
+      apply (rule is_aligned_mult_triv2)
+     apply simp
+    apply (erule order_le_less_trans, simp)
+   apply simp+
+  done
+
 end
 
 end