From 4abaa3fa312fcbe7ee9665853f52a5d37e703864 Mon Sep 17 00:00:00 2001 From: xleroy Date: Sun, 1 Jul 2012 07:51:12 +0000 Subject: Recombine x = cmp(...); if (x == 1) ... and x = cmp(...); if (x != 1) ... git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@1946 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e --- ia32/CombineOp.v | 28 ++++++++++++++++++++++++---- ia32/CombineOpproof.v | 29 +++++++++++++++++++++++++++++ 2 files changed, 53 insertions(+), 4 deletions(-) (limited to 'ia32') diff --git a/ia32/CombineOp.v b/ia32/CombineOp.v index 1391f55..07d5a79 100644 --- a/ia32/CombineOp.v +++ b/ia32/CombineOp.v @@ -43,16 +43,36 @@ Function combine_compimm_eq_0 (x: valnum) : option(condition * list valnum) := | _ => None end. +Function combine_compimm_eq_1 (x: valnum) : option(condition * list valnum) := + match get x with + | Some(Op (Ocmp c) ys) => Some (c, ys) + | _ => None + end. + +Function combine_compimm_ne_1 (x: valnum) : option(condition * list valnum) := + match get x with + | Some(Op (Ocmp c) ys) => Some (negate_condition c, ys) + | _ => None + end. + Function combine_cond (cond: condition) (args: list valnum) : option(condition * list valnum) := match cond, args with | Ccompimm Cne n, x::nil => - if Int.eq_dec n Int.zero then combine_compimm_ne_0 x else None + if Int.eq_dec n Int.zero then combine_compimm_ne_0 x + else if Int.eq_dec n Int.one then combine_compimm_ne_1 x + else None | Ccompimm Ceq n, x::nil => - if Int.eq_dec n Int.zero then combine_compimm_eq_0 x else None + if Int.eq_dec n Int.zero then combine_compimm_eq_0 x + else if Int.eq_dec n Int.one then combine_compimm_eq_1 x + else None | Ccompuimm Cne n, x::nil => - if Int.eq_dec n Int.zero then combine_compimm_ne_0 x else None + if Int.eq_dec n Int.zero then combine_compimm_ne_0 x + else if Int.eq_dec n Int.one then combine_compimm_ne_1 x + else None | Ccompuimm Ceq n, x::nil => - if Int.eq_dec n Int.zero then combine_compimm_eq_0 x else None + if Int.eq_dec n Int.zero then combine_compimm_eq_0 x + else if Int.eq_dec n Int.one then combine_compimm_eq_1 x + else None | _, _ => None end. diff --git a/ia32/CombineOpproof.v b/ia32/CombineOpproof.v index 2f1fe7b..4e07bf5 100644 --- a/ia32/CombineOpproof.v +++ b/ia32/CombineOpproof.v @@ -66,6 +66,31 @@ Proof. intros EQ; inv EQ. destruct (valu v); simpl; auto. Qed. +Lemma combine_compimm_eq_1_sound: + forall x cond args, + combine_compimm_eq_1 get x = Some(cond, args) -> + eval_condition cond (map valu args) m = Val.cmp_bool Ceq (valu x) (Vint Int.one) /\ + eval_condition cond (map valu args) m = Val.cmpu_bool (Mem.valid_pointer m) Ceq (valu x) (Vint Int.one). +Proof. + intros until args. functional induction (combine_compimm_eq_1 get x); intros EQ; inv EQ. + (* of cmp *) + exploit get_sound; eauto. unfold equation_holds. simpl. intro EQ; inv EQ. + destruct (eval_condition cond (map valu args) m); simpl; auto. destruct b; auto. +Qed. + +Lemma combine_compimm_ne_1_sound: + forall x cond args, + combine_compimm_ne_1 get x = Some(cond, args) -> + eval_condition cond (map valu args) m = Val.cmp_bool Cne (valu x) (Vint Int.one) /\ + eval_condition cond (map valu args) m = Val.cmpu_bool (Mem.valid_pointer m) Cne (valu x) (Vint Int.one). +Proof. + intros until args. functional induction (combine_compimm_eq_1 get x); intros EQ; inv EQ. + (* of cmp *) + exploit get_sound; eauto. unfold equation_holds. simpl. intro EQ; inv EQ. + rewrite eval_negate_condition. + destruct (eval_condition cond (map valu args) m); simpl; auto. destruct b; auto. +Qed. + Theorem combine_cond_sound: forall cond args cond' args', combine_cond get cond args = Some(cond', args') -> @@ -76,10 +101,14 @@ Proof. simpl; eapply combine_compimm_ne_0_sound; eauto. (* compimm eq zero *) simpl; eapply combine_compimm_eq_0_sound; eauto. + (* compimm eq one *) + simpl; eapply combine_compimm_eq_1_sound; eauto. (* compuimm ne zero *) simpl; eapply combine_compimm_ne_0_sound; eauto. (* compuimm eq zero *) simpl; eapply combine_compimm_eq_0_sound; eauto. + (* compuimm eq one *) + simpl; eapply combine_compimm_eq_1_sound; eauto. Qed. Theorem combine_addr_sound: -- cgit v1.2.3