From: Julian Seward <jseward@acm.org>
Date: Wed, 19 Dec 2012 15:28:43 +0000 (+0000)
Subject: Constant folder: enable Sub32(x,0) ==> x.
X-Git-Tag: svn/VALGRIND_3_9_0^2~187
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d46cf7eae24e0d039cdd299881009c7b7dde3974;p=thirdparty%2Fvalgrind.git

Constant folder: enable Sub32(x,0) ==> x.


git-svn-id: svn://svn.valgrind.org/vex/trunk@2598
---

diff --git a/VEX/priv/ir_opt.c b/VEX/priv/ir_opt.c
index 1537df686f..7a879d484b 100644
--- a/VEX/priv/ir_opt.c
+++ b/VEX/priv/ir_opt.c
@@ -2063,13 +2063,14 @@ static IRExpr* fold_Expr ( IRExpr** env, IRExpr* e )
                }
                break;
 
+            case Iop_Sub32:
             case Iop_Sub64:
-               /* Sub64(x,0) ==> x */
-               if (isZeroU64(e->Iex.Binop.arg2)) {
+               /* Sub32/Sub64(x,0) ==> x */
+               if (isZeroU(e->Iex.Binop.arg2)) {
                   e2 = e->Iex.Binop.arg1;
                   break;
                }
-               /* Sub64(t,t) ==> 0, for some IRTemp t */
+               /* Sub32/Sub64(t,t) ==> 0, for some IRTemp t */
                if (sameIRExprs(env, e->Iex.Binop.arg1, e->Iex.Binop.arg2)) {
                   e2 = mkZeroOfPrimopResultType(e->Iex.Binop.op);
                   break;
@@ -2133,9 +2134,8 @@ static IRExpr* fold_Expr ( IRExpr** env, IRExpr* e )
                }
                break;
 
-            case Iop_Sub32:
             case Iop_CmpNE32:
-               /* Sub32/CmpNE32(t,t) ==> 0, for some IRTemp t */
+               /* CmpNE32(t,t) ==> 0, for some IRTemp t */
                if (sameIRExprs(env, e->Iex.Binop.arg1, e->Iex.Binop.arg2)) {
                   e2 = mkZeroOfPrimopResultType(e->Iex.Binop.op);
                   break;