Commit 00d19664 authored by Simon Pilgrim's avatar Simon Pilgrim
Browse files

[X86] matchIndexRecursively - don't peek through SIGN_EXTEND for vector indices 

Don't rely on implicit extension for gather/scatter ops
parent d43f324f

llvm/lib/Target/X86/X86ISelDAGToDAG.cpp

+3 −2
Original line number Diff line number Diff line
@@ -2225,6 +2225,8 @@ SDValue X86DAGToDAGISel::matchIndexRecursively(SDValue N, 
  if (Depth >= SelectionDAG::MaxRecursionDepth)

    return N;



  EVT VT = N.getValueType();



  // index: add(x,c) -> index: x, disp + c

  if (CurDAG->isBaseWithConstantOffset(N)) {

    auto *AddVal = cast<ConstantSDNode>(N.getOperand(1));
@@ -2253,7 +2255,7 @@ SDValue X86DAGToDAGISel::matchIndexRecursively(SDValue N, 


  // index: sext(add_nsw(x,c)) -> index: sext(x), disp + sext(c)

  // TODO: call matchIndexRecursively(AddSrc) if we won't corrupt sext?

  if (N.getOpcode() == ISD::SIGN_EXTEND) {

  if (N.getOpcode() == ISD::SIGN_EXTEND && !VT.isVector()) {

    SDValue Src = N.getOperand(0);

    if (Src.getOpcode() == ISD::ADD && Src->getFlags().hasNoSignedWrap()) {

      if (CurDAG->isBaseWithConstantOffset(Src)) {
@@ -2262,7 +2264,6 @@ SDValue X86DAGToDAGISel::matchIndexRecursively(SDValue N, 
        uint64_t Offset = (uint64_t)AddVal->getSExtValue() * AM.Scale;

        if (!foldOffsetIntoAddress(Offset, AM)) {

          SDLoc DL(N);

          EVT VT = N.getValueType();

          SDValue ExtSrc = CurDAG->getNode(ISD::SIGN_EXTEND, DL, VT, AddSrc);

          SDValue ExtVal = CurDAG->getConstant(AddVal->getSExtValue(), DL, VT);

          SDValue ExtAdd = CurDAG->getNode(ISD::ADD, DL, VT, ExtSrc, ExtVal);