diff options
Diffstat (limited to 'lib/CodeGen')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp index 653614379d..9bd8bb521b 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp @@ -696,12 +696,25 @@ SDValue DAGTypeLegalizer::PromoteIntOp_BRCOND(SDNode *N, unsigned OpNo) { assert(OpNo == 1 && "only know how to promote condition"); SDValue Cond = GetPromotedInteger(N->getOperand(1)); // Promote condition. - // The top bits of the promoted condition are not necessarily zero, ensure - // that the value is properly zero extended. - unsigned BitWidth = Cond.getValueSizeInBits(); - if (!DAG.MaskedValueIsZero(Cond, - APInt::getHighBitsSet(BitWidth, BitWidth-1))) - Cond = DAG.getZeroExtendInReg(Cond, MVT::i1); + // Make sure the extra bits coming from type promotion conform to + // getSetCCResultContents. + unsigned CondBits = Cond.getValueSizeInBits(); + switch (TLI.getSetCCResultContents()) { + default: + assert(false && "Unknown SetCCResultValue!"); + case TargetLowering::UndefinedSetCCResult: + // The promoted value, which may contain rubbish in the upper bits, is fine. + break; + case TargetLowering::ZeroOrOneSetCCResult: + if (!DAG.MaskedValueIsZero(Cond,APInt::getHighBitsSet(CondBits,CondBits-1))) + Cond = DAG.getZeroExtendInReg(Cond, MVT::i1); + break; + case TargetLowering::ZeroOrNegativeOneSetCCResult: + if (DAG.ComputeNumSignBits(Cond) != CondBits) + Cond = DAG.getNode(ISD::SIGN_EXTEND_INREG, Cond.getValueType(), Cond, + DAG.getValueType(MVT::i1)); + break; + } // The chain (Op#0) and basic block destination (Op#2) are always legal types. return DAG.UpdateNodeOperands(SDValue(N, 0), N->getOperand(0), Cond, |