diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/TargetLowering.cpp')
-rw-r--r-- | lib/CodeGen/SelectionDAG/TargetLowering.cpp | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp index 6212918d6c..2aed084800 100644 --- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -2390,21 +2390,29 @@ TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1, } if (N0 == N1) { + // The sext(setcc()) => setcc() optimization relies on the appropriate + // constant being emitted. + uint64_t EqVal; + switch (getBooleanContents(N0.getValueType().isVector())) { + default: llvm_unreachable("Unknown boolean contents!"); + case UndefinedBooleanContent: + case ZeroOrOneBooleanContent: + EqVal = ISD::isTrueWhenEqual(Cond); + break; + case ZeroOrNegativeOneBooleanContent: + EqVal = ISD::isTrueWhenEqual(Cond) ? -1 : 0; + break; + } + // We can always fold X == X for integer setcc's. if (N0.getValueType().isInteger()) { - switch (getBooleanContents(N0.getValueType().isVector())) { - case UndefinedBooleanContent: - case ZeroOrOneBooleanContent: - return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT); - case ZeroOrNegativeOneBooleanContent: - return DAG.getConstant(ISD::isTrueWhenEqual(Cond) ? -1 : 0, VT); - } + return DAG.getConstant(EqVal, VT); } unsigned UOF = ISD::getUnorderedFlavor(Cond); if (UOF == 2) // FP operators that are undefined on NaNs. - return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT); + return DAG.getConstant(EqVal, VT); if (UOF == unsigned(ISD::isTrueWhenEqual(Cond))) - return DAG.getConstant(UOF, VT); + return DAG.getConstant(EqVal, VT); // Otherwise, we can't fold it. However, we can simplify it to SETUO/SETO // if it is not already. ISD::CondCode NewCond = UOF == 0 ? ISD::SETO : ISD::SETUO; |