diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 8f74d6a2a71..39fd95e7d2c 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -4767,6 +4767,18 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT, } } + // Any FP binop with an undef operand is folded to NaN. This matches the + // behavior of the IR optimizer. + switch (Opcode) { + case ISD::FADD: + case ISD::FSUB: + case ISD::FMUL: + case ISD::FDIV: + case ISD::FREM: + if (N1.isUndef() || N2.isUndef()) + return getConstantFP(APFloat::getNaN(EVTToAPFloatSemantics(VT)), DL, VT); + } + // Canonicalize an UNDEF to the RHS, even over a constant. if (N1.isUndef()) { if (TLI->isCommutativeBinOp(Opcode)) { @@ -4776,9 +4788,6 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT, case ISD::FP_ROUND_INREG: case ISD::SIGN_EXTEND_INREG: case ISD::SUB: - case ISD::FSUB: - case ISD::FDIV: - case ISD::FREM: return getUNDEF(VT); // fold op(undef, arg2) -> undef case ISD::UDIV: case ISD::SDIV: @@ -4813,14 +4822,6 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT, case ISD::SRL: case ISD::SHL: return getUNDEF(VT); // fold op(arg1, undef) -> undef - case ISD::FADD: - case ISD::FSUB: - case ISD::FMUL: - case ISD::FDIV: - case ISD::FREM: - if (getTarget().Options.UnsafeFPMath) - return N2; - break; case ISD::MUL: case ISD::AND: return getConstant(0, DL, VT); // fold op(arg1, undef) -> 0 |
