[X86] getFauxShuffleMask - OR(BITCAST(SHUFFLE()),BITCAST(SHUFFLE())) patterns should return bitcasted source values #134993
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…patterns should return bitcasted source values Noticed while investigating llvm#133947 regressions - if we peek through bitcasts we can lose track of oneuse/combined nodes Same current codegen as combineX86ShufflesRecursively still peeks through the bitcasts itself, but we will soon handle this consistently as another part of llvm#133947
|
@llvm/pr-subscribers-backend-x86 Author: Simon Pilgrim (RKSimon) ChangesNoticed while investigating #133947 regressions - if we peek through bitcasts we can lose track of oneuse/combined nodes in shuffle combining Currently the same codegen as combineX86ShufflesRecursively still peeks through the bitcasts itself, but we will soon handle this consistently as another part of #133947 Full diff: https://github.com/llvm/llvm-project/pull/134993.diff 1 Files Affected:
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 47ac1ee571269..53bed634c3cc6 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -6155,8 +6155,8 @@ static bool getFauxShuffleMask(SDValue N, const APInt &DemandedElts,
else
return false;
}
- Ops.push_back(N0);
- Ops.push_back(N1);
+ Ops.push_back(N.getOperand(0));
+ Ops.push_back(N.getOperand(1));
return true;
}
case ISD::CONCAT_VECTORS: {
|
AllinLeeYL
pushed a commit
to AllinLeeYL/llvm-project
that referenced
this pull request
Apr 10, 2025
…patterns should return bitcasted source values (llvm#134993) Noticed while investigating llvm#133947 regressions - if we peek through bitcasts we can lose track of oneuse/combined nodes in shuffle combining Currently the same codegen as combineX86ShufflesRecursively still peeks through the bitcasts itself, but we will soon handle this consistently as another part of llvm#133947
var-const
pushed a commit
to ldionne/llvm-project
that referenced
this pull request
Apr 17, 2025
…patterns should return bitcasted source values (llvm#134993) Noticed while investigating llvm#133947 regressions - if we peek through bitcasts we can lose track of oneuse/combined nodes in shuffle combining Currently the same codegen as combineX86ShufflesRecursively still peeks through the bitcasts itself, but we will soon handle this consistently as another part of llvm#133947
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Noticed while investigating #133947 regressions - if we peek through bitcasts we can lose track of oneuse/combined nodes in shuffle combining
Currently the same codegen as combineX86ShufflesRecursively still peeks through the bitcasts itself, but we will soon handle this consistently as another part of #133947