- VEXTOffsets[i] = MinElts[i];
- SDValue VEXTSrc1 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VT,
- SourceVecs[i],
- DAG.getIntPtrConstant(0, dl));
- SDValue VEXTSrc2 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VT,
- SourceVecs[i],
- DAG.getIntPtrConstant(NumElts, dl));
- ShuffleSrcs[i] = DAG.getNode(ARMISD::VEXT, dl, VT, VEXTSrc1, VEXTSrc2,
- DAG.getConstant(VEXTOffsets[i], dl,
- MVT::i32));
- }
- }
-
- SmallVector<int, 8> Mask;
-
- for (unsigned i = 0; i < NumElts; ++i) {
+ SDValue VEXTSrc1 =
+ DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, DestVT, Src.ShuffleVec,
+ DAG.getConstant(0, dl, MVT::i32));
+ SDValue VEXTSrc2 =
+ DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, DestVT, Src.ShuffleVec,
+ DAG.getConstant(NumSrcElts, dl, MVT::i32));
+ unsigned Imm = Src.MinElt * getExtFactor(VEXTSrc1);
+
+ Src.ShuffleVec = DAG.getNode(ARMISD::VEXT, dl, DestVT, VEXTSrc1,
+ VEXTSrc2,
+ DAG.getConstant(Imm, dl, MVT::i32));
+ Src.WindowBase = -Src.MinElt;
+ }
+ }
+
+ // Another possible incompatibility occurs from the vector element types. We
+ // can fix this by bitcasting the source vectors to the same type we intend
+ // for the shuffle.
+ for (auto &Src : Sources) {
+ EVT SrcEltTy = Src.ShuffleVec.getValueType().getVectorElementType();
+ if (SrcEltTy == SmallestEltTy)
+ continue;
+ assert(ShuffleVT.getVectorElementType() == SmallestEltTy);
+ Src.ShuffleVec = DAG.getNode(ISD::BITCAST, dl, ShuffleVT, Src.ShuffleVec);
+ Src.WindowScale = SrcEltTy.getSizeInBits() / SmallestEltTy.getSizeInBits();
+ Src.WindowBase *= Src.WindowScale;
+ }
+
+ // Final sanity check before we try to actually produce a shuffle.
+ DEBUG(
+ for (auto Src : Sources)
+ assert(Src.ShuffleVec.getValueType() == ShuffleVT);
+ );
+
+ // The stars all align, our next step is to produce the mask for the shuffle.
+ SmallVector<int, 8> Mask(ShuffleVT.getVectorNumElements(), -1);
+ int BitsPerShuffleLane = ShuffleVT.getVectorElementType().getSizeInBits();
+ for (unsigned i = 0; i < VT.getVectorNumElements(); ++i) {