Skip to content

[GISel][SDAG] Avoid push_back in loops for some shuffle mask handling. #119434

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Dec 11, 2024
Merged

[GISel][SDAG] Avoid push_back in loops for some shuffle mask handling. #119434

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b8bc3d8
[GISel][SDAG] Avoid push_back in loops for some shuffle mask handling.
topperc Dec 10, 2024
2c9d19f
fixup! Address review comments.
topperc Dec 10, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
13 changes: 5 additions & 8 deletions llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6172,9 +6172,8 @@ LegalizerHelper::equalizeVectorShuffleLengths(MachineInstr &MI) {
if (MaskNumElts < SrcNumElts) {
// Extend mask to match new destination vector size with
// undef values.
SmallVector<int, 16> NewMask(Mask);
for (unsigned I = MaskNumElts; I < SrcNumElts; ++I)
NewMask.push_back(-1);
SmallVector<int, 16> NewMask(SrcNumElts, -1);
llvm::copy(Mask, NewMask.begin());

moreElementsVectorDst(MI, SrcTy, 0);
MIRBuilder.setInstrAndDebugLoc(MI);
Expand Down Expand Up @@ -6254,16 +6253,14 @@ LegalizerHelper::moreElementsVectorShuffle(MachineInstr &MI,
moreElementsVectorSrc(MI, MoreTy, 2);

// Adjust mask based on new input vector length.
SmallVector<int, 16> NewMask;
SmallVector<int, 16> NewMask(WidenNumElts, -1);
for (unsigned I = 0; I != NumElts; ++I) {
int Idx = Mask[I];
if (Idx < static_cast<int>(NumElts))
NewMask.push_back(Idx);
NewMask[I] = Idx;
else
NewMask.push_back(Idx - NumElts + WidenNumElts);
NewMask[I] = Idx - NumElts + WidenNumElts;
}
for (unsigned I = NumElts; I != WidenNumElts; ++I)
NewMask.push_back(-1);
moreElementsVectorDst(MI, MoreTy, 0);
MIRBuilder.setInstrAndDebugLoc(MI);
MIRBuilder.buildShuffleVector(MI.getOperand(0).getReg(),
Expand Down
16 changes: 5 additions & 11 deletions llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6421,16 +6421,14 @@ SDValue DAGTypeLegalizer::WidenVecRes_VECTOR_SHUFFLE(ShuffleVectorSDNode *N) {
SDValue InOp2 = GetWidenedVector(N->getOperand(1));

// Adjust mask based on new input vector length.
SmallVector<int, 16> NewMask;
SmallVector<int, 16> NewMask(WidenNumElts, -1);
for (unsigned i = 0; i != NumElts; ++i) {
int Idx = N->getMaskElt(i);
if (Idx < (int)NumElts)
NewMask.push_back(Idx);
NewMask[i] = Idx;
else
NewMask.push_back(Idx - NumElts + WidenNumElts);
NewMask[i] = Idx - NumElts + WidenNumElts;
}
for (unsigned i = NumElts; i != WidenNumElts; ++i)
NewMask.push_back(-1);
return DAG.getVectorShuffle(WidenVT, dl, InOp1, InOp2, NewMask);
}

Expand Down Expand Up @@ -6478,12 +6476,8 @@ SDValue DAGTypeLegalizer::WidenVecRes_VECTOR_REVERSE(SDNode *N) {

// Use VECTOR_SHUFFLE to combine new vector from 'ReverseVal' for
// fixed-vectors.
SmallVector<int, 16> Mask;
for (unsigned i = 0; i != VTNumElts; ++i) {
Mask.push_back(IdxVal + i);
}
for (unsigned i = VTNumElts; i != WidenNumElts; ++i)
Mask.push_back(-1);
SmallVector<int, 16> Mask(WidenNumElts, -1);
Copy link
Collaborator Author

@topperc topperc Dec 10, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This code isn't tested because VECTOR_REVERSE is converted to a generic VECTOR_SHUFFLE for fixed vectors.

std::iota(Mask.begin(), Mask.begin() + VTNumElts, IdxVal);

return DAG.getVectorShuffle(WidenVT, dl, ReverseVal, DAG.getUNDEF(WidenVT),
Mask);
Expand Down
Loading