DAGCombine: prevent formation of illegal ConstantFP nodes.
llvm-svn: 207850
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 290f2a1..de715e4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -7181,11 +7181,16 @@
// (fneg (fmul c, x)) -> (fmul -c, x)
if (N0.getOpcode() == ISD::FMUL) {
ConstantFPSDNode *CFP1 = dyn_cast<ConstantFPSDNode>(N0.getOperand(1));
- if (CFP1)
- return DAG.getNode(ISD::FMUL, SDLoc(N), VT,
- N0.getOperand(0),
- DAG.getNode(ISD::FNEG, SDLoc(N), VT,
- N0.getOperand(1)));
+ if (CFP1) {
+ APFloat CVal = CFP1->getValueAPF();
+ CVal.changeSign();
+ if (Level >= AfterLegalizeDAG &&
+ (TLI.isFPImmLegal(CVal, N->getValueType(0)) ||
+ TLI.isOperationLegal(ISD::ConstantFP, N->getValueType(0))))
+ return DAG.getNode(
+ ISD::FMUL, SDLoc(N), VT, N0.getOperand(0),
+ DAG.getNode(ISD::FNEG, SDLoc(N), VT, N0.getOperand(1)));
+ }
}
return SDValue();