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[X86][NFC] Use std::move to avoid copy #141455

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Merged
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Jun 21, 2025
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[X86][NFC] Use std::move to avoid copy #141455

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2 changes: 1 addition & 1 deletion llvm/lib/Target/X86/X86ISelLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -41193,7 +41193,7 @@ static SDValue combineX86ShufflesRecursively(
resolveTargetShuffleFromZeroables(OpMask, OpUndef, OpZero,
ResolveKnownZeros);

Mask = OpMask;
Mask = std::move(OpMask);
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@topperc topperc Jun 21, 2025

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Since OpMask and Mask are SmallVectors, this doesn't avoid a copy if the small storage is being used. The data has to be copied from the small storage of OpMask. I believe the SmallVectors are sized so that they are always using the small size.

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@abhishek-kaushik22 abhishek-kaushik22 Jun 22, 2025

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Sorry, I have reverted this.

Ops.append(OpInputs.begin(), OpInputs.end());
} else {
resolveTargetShuffleFromZeroables(OpMask, OpUndef, OpZero);
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