diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 1c90f78435..a559d3e469 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -2419,7 +2419,17 @@ SDOperand DAGCombiner::visitVBUILD_VECTOR(SDNode *N) { // Return the new VVECTOR_SHUFFLE node. std::vector<SDOperand> Ops; Ops.push_back(VecIn1); - Ops.push_back(VecIn2.Val ? VecIn2 : VecIn1); // Use V1 twice if no V2. + if (VecIn2.Val) { + Ops.push_back(VecIn2); + } else { + // Use an undef vbuild_vector as input for the second operand. + std::vector<SDOperand> UnOps(NumInScalars, + DAG.getNode(ISD::UNDEF, + cast<VTSDNode>(EltType)->getVT())); + UnOps.push_back(NumElts); + UnOps.push_back(EltType); + Ops.push_back(DAG.getNode(ISD::VBUILD_VECTOR, MVT::Vector, UnOps)); + } Ops.push_back(DAG.getNode(ISD::VBUILD_VECTOR,MVT::Vector, BuildVecIndices)); Ops.push_back(NumElts); Ops.push_back(EltType); |