Preserve fast-math flags when folding (fsub x, (fneg y)) to (fadd x, y).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187462 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index 1fa6897..534feb8 100644
--- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -1530,17 +1530,24 @@
// If this is a 'B = x-(-A)', change to B = x+A, potentially looking
// through FP extensions/truncations along the way.
- if (Value *V = dyn_castFNegVal(Op1))
- return BinaryOperator::CreateFAdd(Op0, V);
+ if (Value *V = dyn_castFNegVal(Op1)) {
+ Instruction *NewI = BinaryOperator::CreateFAdd(Op0, V);
+ NewI->copyFastMathFlags(&I);
+ return NewI;
+ }
if (FPTruncInst *FPTI = dyn_cast<FPTruncInst>(Op1)) {
if (Value *V = dyn_castFNegVal(FPTI->getOperand(0))) {
Value *NewTrunc = Builder->CreateFPTrunc(V, I.getType());
- return BinaryOperator::CreateFAdd(Op0, NewTrunc);
+ Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewTrunc);
+ NewI->copyFastMathFlags(&I);
+ return NewI;
}
} else if (FPExtInst *FPEI = dyn_cast<FPExtInst>(Op1)) {
if (Value *V = dyn_castFNegVal(FPEI->getOperand(0))) {
Value *NewExt = Builder->CreateFPExt(V, I.getType());
- return BinaryOperator::CreateFAdd(Op0, NewExt);
+ Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewExt);
+ NewI->copyFastMathFlags(&I);
+ return NewI;
}
}