diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 85747ac623b..026572222ea 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -2906,9 +2906,20 @@ unsigned SelectionDAG::ComputeNumSignBits(SDValue Op, unsigned Depth) const { } case ISD::BUILD_VECTOR: - Tmp = ComputeNumSignBits(Op.getOperand(0), Depth + 1); - for (unsigned i = 1, e = Op.getNumOperands(); (i < e) && (Tmp > 1); ++i) - Tmp = std::min(Tmp, ComputeNumSignBits(Op.getOperand(i), Depth + 1)); + Tmp = VTBits; + for (unsigned i = 0, e = Op.getNumOperands(); (i < e) && (Tmp > 1); ++i) { + SDValue SrcOp = Op.getOperand(i); + Tmp2 = ComputeNumSignBits(Op.getOperand(i), Depth + 1); + + // BUILD_VECTOR can implicitly truncate sources, we must handle this. + if (SrcOp.getValueSizeInBits() != VTBits) { + assert(SrcOp.getValueSizeInBits() > VTBits && + "Expected BUILD_VECTOR implicit truncation"); + unsigned ExtraBits = SrcOp.getValueSizeInBits() - VTBits; + Tmp2 = (Tmp2 > ExtraBits ? Tmp2 - ExtraBits : 1); + } + Tmp = std::min(Tmp, Tmp2); + } return Tmp; case ISD::SIGN_EXTEND: |
