diff options
Diffstat (limited to 'llvm/lib/Target/R600/AMDGPUISelLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/R600/AMDGPUISelLowering.cpp | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp index a4cb4f5c405..6c443ea828b 100644 --- a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp +++ b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp @@ -1377,6 +1377,20 @@ SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N, unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom); if (OpSignBits >= SignBits) return BitsFrom; + + EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal); + if (Signed) { + // This is a sign_extend_inreg. Replace it to take advantage of existing + // DAG Combines. If not eliminated, we will match back to BFE during + // selection. + + // TODO: The sext_inreg of extended types ends, although we can could + // handle them in a single BFE. + return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom, + DAG.getValueType(SmallVT)); + } + + return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT); } if (ConstantSDNode *Val = dyn_cast<ConstantSDNode>(N->getOperand(0))) { @@ -1396,6 +1410,13 @@ SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N, APInt Demanded = APInt::getBitsSet(32, OffsetVal, OffsetVal + WidthVal); + + if ((OffsetVal + WidthVal) >= 32) { + SDValue ShiftVal = DAG.getConstant(OffsetVal, MVT::i32); + return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32, + BitsFrom, ShiftVal); + } + APInt KnownZero, KnownOne; TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(), !DCI.isBeforeLegalizeOps()); |
