diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index bda9d934a4..f5287b0cf2 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -2357,7 +2357,8 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL, return Operand.getOperand(0); break; case ISD::FNEG: - if (OpOpcode == ISD::FSUB) // -(X-Y) -> (Y-X) + // -(X-Y) -> (Y-X) is unsafe because when X==Y, -0.0 != +0.0 + if (UnsafeFPMath && OpOpcode == ISD::FSUB) return getNode(ISD::FSUB, VT, Operand.getNode()->getOperand(1), Operand.getNode()->getOperand(0)); if (OpOpcode == ISD::FNEG) // --X -> X |