[Reassociate] Don't propogate flags when creating negations

[oota-llvm.git] / lib / Transforms / Scalar / Reassociate.cpp

diff --git a/lib/Transforms/Scalar/Reassociate.cpp b/lib/Transforms/Scalar/Reassociate.cpp
index 6c66b58729e9a5d08691f4c42038fc28cf30fd49..d1acf785d07ec7e01003346cde9d878fddfac10f 100644 (file)
--- a/lib/Transforms/Scalar/Reassociate.cpp
+++ b/lib/Transforms/Scalar/Reassociate.cpp
@@ -936,6 +936,10 @@ static Value *NegateValue(Value *V, Instruction *BI) {
     // Push the negates through the add.
     I->setOperand(0, NegateValue(I->getOperand(0), BI));
     I->setOperand(1, NegateValue(I->getOperand(1), BI));
+    if (I->getOpcode() == Instruction::Add) {
+      I->setHasNoUnsignedWrap(false);
+      I->setHasNoSignedWrap(false);
+    }
 
     // We must move the add instruction here, because the neg instructions do
     // not dominate the old add instruction in general.  By moving it, we are
@@ -976,6 +980,12 @@ static Value *NegateValue(Value *V, Instruction *BI) {
       InsertPt = TheNeg->getParent()->getParent()->getEntryBlock().begin();
     }
     TheNeg->moveBefore(InsertPt);
+    if (TheNeg->getOpcode() == Instruction::Sub) {
+      TheNeg->setHasNoUnsignedWrap(false);
+      TheNeg->setHasNoSignedWrap(false);
+    } else {
+      TheNeg->andIRFlags(BI);
+    }
     return TheNeg;
   }