diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 3b14e00efab..3597c6d86c5 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -4482,6 +4482,10 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT, return Operand.getOperand(0); break; case ISD::FNEG: + // Negation of an unknown bag of bits is still completely undefined. + if (OpOpcode == ISD::UNDEF) + return getUNDEF(VT); + // -(X-Y) -> (Y-X) is unsafe because when X==Y, -0.0 != +0.0 if ((getTarget().Options.UnsafeFPMath || Flags.hasNoSignedZeros()) && OpOpcode == ISD::FSUB) |
