[InstCombine] fix propagation of fast-math-flags
Noticed while working on D4583:
http://reviews.llvm.org/D4583
llvm-svn: 253997
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 10a517a..e95a655 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1245,16 +1245,11 @@
/// specified one but with other operands.
static Value *CreateBinOpAsGiven(BinaryOperator &Inst, Value *LHS, Value *RHS,
InstCombiner::BuilderTy *B) {
- Value *BORes = B->CreateBinOp(Inst.getOpcode(), LHS, RHS);
- if (BinaryOperator *NewBO = dyn_cast<BinaryOperator>(BORes)) {
- if (isa<OverflowingBinaryOperator>(NewBO)) {
- NewBO->setHasNoSignedWrap(Inst.hasNoSignedWrap());
- NewBO->setHasNoUnsignedWrap(Inst.hasNoUnsignedWrap());
- }
- if (isa<PossiblyExactOperator>(NewBO))
- NewBO->setIsExact(Inst.isExact());
- }
- return BORes;
+ Value *BO = B->CreateBinOp(Inst.getOpcode(), LHS, RHS);
+ // If LHS and RHS are constant, BO won't be a binary operator.
+ if (BinaryOperator *NewBO = dyn_cast<BinaryOperator>(BO))
+ NewBO->copyIRFlags(&Inst);
+ return BO;
}
/// \brief Makes transformation of binary operation specific for vector types.