diff options
Diffstat (limited to 'backend')
| -rw-r--r-- | backend/NeedDomain.v | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/backend/NeedDomain.v b/backend/NeedDomain.v index 99d70a8..47f6975 100644 --- a/backend/NeedDomain.v +++ b/backend/NeedDomain.v @@ -603,7 +603,7 @@ Proof. - destruct v; auto with na. Qed. -(** Modular arithmetic operations: add, mul. +(** Modular arithmetic operations: add, mul, opposite. (But not subtraction because of the pointer - pointer case. *) Definition modarith (x: nval) := @@ -642,6 +642,19 @@ Proof. - inv H; auto. inv H0; auto. destruct w1; auto. Qed. +Lemma neg_sound: + forall v w x, + vagree v w (modarith x) -> + vagree (Val.neg v) (Val.neg w) x. +Proof. + intros; destruct x; simpl in *. +- auto. +- unfold Val.neg; InvAgree. + apply eqmod_iagree. apply Int.eqmod_neg. apply iagree_eqmod; auto. +- destruct v, w; simpl; auto. +- inv H; simpl; auto. +Qed. + (** Conversions: zero extension, sign extension, single-of-float *) Definition zero_ext (n: Z) (x: nval) := |