Index: lib/CodeGen/SelectionDAG/LegalizeDAG.cpp =================================================================== --- lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -4438,6 +4438,34 @@ Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewVec)); break; } + case ISD::SCALAR_TO_VECTOR: { + MVT EltVT = OVT.getVectorElementType(); + MVT NewEltVT = NVT.getVectorElementType(); + + // Handle bitcasts to different vector type with the smae total bit size. + // + // e.g. v2i64 = scalar_to_vector x:i64 + // => + // concat_vectors (v2i32 bitcast x:i64), (v2i32 undef) + // + + MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT); + SDValue Val = Node->getOperand(0); + SDLoc SL(Node); + + SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, MidVT, Val); + SDValue Undef = DAG.getUNDEF(MidVT); + + SmallVector NewElts; + NewElts.push_back(CastVal); + for (unsigned I = 1, NElts = OVT.getVectorNumElements(); I != NElts; ++I) + NewElts.push_back(Undef); + + SDValue Concat = DAG.getNode(ISD::CONCAT_VECTORS, SL, NVT, NewElts); + SDValue CvtVec = DAG.getNode(ISD::BITCAST, SL, OVT, Concat); + Results.push_back(CvtVec); + break; + } } // Replace the original node with the legalized result.