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isabelle2021-1 word_lib: tweak word_eqI method 

More controlled simpset setup, so we don't get warnings if we have
bit_simps in the simpset already.

Signed-off-by: Gerwin Klein <gerwin.klein@proofcraft.systems>
This commit is contained in:
Gerwin Klein 2021-11-16 17:08:50 +11:00 committed by Gerwin Klein
parent a0bf14024e
commit c9f8e023f4
2 changed files with 9 additions and 6 deletions
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9
lib/Word_Lib/Word_EqI.thy
View File

@ -59,12 +59,15 @@ method word_eqI uses simp simp_del split split_del cong flip =
(* turn x < 2^n assumptions into mask equations: *)
((drule less_mask_eq)+)?,
(* expand and distribute test_bit everywhere: *)
(clarsimp simp: bit_simps word_eqI_simps simp not_less not_le simp del: simp_del simp flip: flip
(simp only: bit_simps word_eqI_simps)?,
(* clarsimp normal form again, also resolve negated < and \<le> *)
(clarsimp simp: simp not_less not_le 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: bit_simps word_eqI_simps simp simp del: simp_del simp flip: flip
(simp only: bit_simps word_eqI_simps)?,
(clarsimp simp: 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)?)
@ -72,7 +75,7 @@ method word_eqI uses simp simp_del split split_del cong flip =
method word_eqI_solve uses simp simp_del split split_del cong flip dest =
solves \<open>word_eqI simp: simp simp_del: simp_del split: split split_del: split_del
cong: cong simp flip: flip;
(fastforce dest: dest simp: bit_simps word_eqI_simps simp flip: flip
(fastforce dest: dest simp: simp flip: flip
simp: simp simp del: simp_del split: split split del: split_del cong: cong)?\<close>
end

6
lib/Word_Lib/Word_Lemmas.thy
View File

@ -1020,11 +1020,11 @@ lemma word_and_less':
lemma shiftr_w2p:
"x < LENGTH('a) \<Longrightarrow> 2 ^ x = (2 ^ (LENGTH('a) - 1) >> (LENGTH('a) - 1 - x) :: 'a :: len word)"
by (rule bit_word_eqI) (auto simp add: bit_simps)
by word_eqI_solve
lemma t2p_shiftr:
"\<lbrakk> b \<le> a; a < LENGTH('a) \<rbrakk> \<Longrightarrow> (2 :: 'a :: len word) ^ a >> b = 2 ^ (a - b)"
by (rule bit_word_eqI) (auto simp add: bit_simps)
by word_eqI_solve
lemma scast_1[simp]:
"scast (1 :: 'a :: len signed word) = (1 :: 'a word)"
@ -1360,7 +1360,7 @@ lemma unat_2tp_if:
lemma mask_of_mask:
"mask (n::nat) AND mask (m::nat) = (mask (min m n) :: 'a::len word)"
by (rule bit_word_eqI) (auto simp add: bit_simps)
by word_eqI_solve
lemma unat_signed_ucast_less_ucast:
"LENGTH('a) \<le> LENGTH('b) \<Longrightarrow> unat (ucast (x :: 'a :: len word) :: 'b :: len signed word) = unat x"