diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 157b0a26b4e..424942b3e9b 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1396,8 +1396,16 @@ SDOperand DAGCombiner::visitXOR(SDNode *N) { DAG.getConstant(N1C->getValue()^N01C->getValue(), VT)); } // fold (xor x, x) -> 0 - if (N0 == N1) - return DAG.getConstant(0, VT); + if (N0 == N1) { + if (!MVT::isVector(VT)) { + return DAG.getConstant(0, VT); + } else if (!AfterLegalize || TLI.isOperationLegal(ISD::BUILD_VECTOR, VT)) { + // Produce a vector of zeros. + SDOperand El = DAG.getConstant(0, MVT::getVectorBaseType(VT)); + std::vector Ops(MVT::getVectorNumElements(VT), El); + return DAG.getNode(ISD::BUILD_VECTOR, VT, Ops); + } + } // fold (xor (zext x), (zext y)) -> (zext (xor x, y)) if (N0.getOpcode() == ISD::ZERO_EXTEND && N1.getOpcode() == ISD::ZERO_EXTEND &&