diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/LegalizeDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index 7549569636..225d2b39df 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -4697,8 +4697,20 @@ SDOperand SelectionDAGLegalize::PackVectorOp(SDOperand Op, Result = Node->getOperand(0); } else { // Returning a BUILD_VECTOR? - std::vector<SDOperand> Ops(Node->op_begin(), Node->op_end()-2); - Result = DAG.getNode(ISD::BUILD_VECTOR, NewVT, Ops); + + // If all elements of the build_vector are undefs, return an undef. + bool AllUndef = true; + for (unsigned i = 0, e = Node->getNumOperands()-2; i != e; ++i) + if (Node->getOperand(i).getOpcode() != ISD::UNDEF) { + AllUndef = false; + break; + } + if (AllUndef) { + Result = DAG.getNode(ISD::UNDEF, NewVT); + } else { + std::vector<SDOperand> Ops(Node->op_begin(), Node->op_end()-2); + Result = DAG.getNode(ISD::BUILD_VECTOR, NewVT, Ops); + } } break; case ISD::VINSERT_VECTOR_ELT: |