diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp index 3bbc8397c92..de77ef94af5 100644 --- a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp +++ b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp @@ -458,8 +458,15 @@ SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) { SH = (Op1Opc == ISD::SHL) ? Value : 32 - Value; } if (Op1Opc == ISD::AND) { + // The AND mask might not be a constant, and we need to make sure that + // if we're going to fold the masking with the insert, all bits not + // know to be zero in the mask are known to be one. + APInt MKZ, MKO; + CurDAG->ComputeMaskedBits(Op1.getOperand(1), MKZ, MKO); + bool CanFoldMask = InsertMask == MKO.getZExtValue(); + unsigned SHOpc = Op1.getOperand(0).getOpcode(); - if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) && + if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) && CanFoldMask && isInt32Immediate(Op1.getOperand(0).getOperand(1), Value)) { // Note that Value must be in range here (less than 32) because // otherwise there would not be any bits set in InsertMask. |
