From: Dan Gohman <gohman@apple.com>
Date: Fri, 9 Oct 2009 00:41:22 +0000 (+0000)
Subject: Preserve HasNSW and HasNUW when constructing SCEVs for Add and Mul
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4db3581a288dcd7e56f0a1ecdc2316cd85e183c7;p=oota-llvm.git

Preserve HasNSW and HasNUW when constructing SCEVs for Add and Mul
instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83606 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 9300de11685..bdf31f9a706 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -2951,12 +2951,20 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
 
   Operator *U = cast<Operator>(V);
   switch (Opcode) {
-  case Instruction::Add:
+  case Instruction::Add: {
+    AddOperator *A = cast<AddOperator>(U);
     return getAddExpr(getSCEV(U->getOperand(0)),
-                      getSCEV(U->getOperand(1)));
-  case Instruction::Mul:
+                      getSCEV(U->getOperand(1)),
+                      A->hasNoUnsignedWrap(),
+                      A->hasNoSignedWrap());
+  }
+  case Instruction::Mul: {
+    MulOperator *M = cast<MulOperator>(U);
     return getMulExpr(getSCEV(U->getOperand(0)),
-                      getSCEV(U->getOperand(1)));
+                      getSCEV(U->getOperand(1)),
+                      M->hasNoUnsignedWrap(),
+                      M->hasNoSignedWrap());
+  }
   case Instruction::UDiv:
     return getUDivExpr(getSCEV(U->getOperand(0)),
                        getSCEV(U->getOperand(1)));