Fix more instances of dropped fast math flags when optimizing FADD instructions. All found by inspection (aka grep).

llvm-svn: 199528

1 files changed, 14 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index 283bec2881f..555ffc77523 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -901,6 +901,11 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
             Value *NegVal;  // Compute -Z
             if (SI.getType()->isFPOrFPVectorTy()) {
               NegVal = Builder->CreateFNeg(SubOp->getOperand(1));
+              if (Instruction *NegInst = dyn_cast<Instruction>(NegVal)) {
+                FastMathFlags Flags = AddOp->getFastMathFlags();
+                Flags &= SubOp->getFastMathFlags();
+                NegInst->setFastMathFlags(Flags);
+              }
             } else {
               NegVal = Builder->CreateNeg(SubOp->getOperand(1));
             }
@@ -913,9 +918,15 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
               Builder->CreateSelect(CondVal, NewTrueOp,
                                     NewFalseOp, SI.getName() + ".p");
 
-            if (SI.getType()->isFPOrFPVectorTy())
-              return BinaryOperator::CreateFAdd(SubOp->getOperand(0), NewSel);
-            else
+            if (SI.getType()->isFPOrFPVectorTy()) {
+              Instruction *RI =
+                BinaryOperator::CreateFAdd(SubOp->getOperand(0), NewSel);
+
+              FastMathFlags Flags = AddOp->getFastMathFlags();
+              Flags &= SubOp->getFastMathFlags();
+              RI->setFastMathFlags(Flags);
+              return RI;
+            } else
               return BinaryOperator::CreateAdd(SubOp->getOperand(0), NewSel);
           }
         }