Fix incorrect Vector256->Vector512 in SpanHelpers#123850
Merged
stephentoub merged 1 commit intodotnet:mainfrom Feb 1, 2026
Merged
Fix incorrect Vector256->Vector512 in SpanHelpers#123850stephentoub merged 1 commit intodotnet:mainfrom
stephentoub merged 1 commit intodotnet:mainfrom
Conversation
Contributor
|
Tagging subscribers to this area: @dotnet/area-system-memory |
Contributor
There was a problem hiding this comment.
Pull request overview
Fixes an incorrect pointer increment in the Vector512 fast-path of NonPackedIndexOfAnyInRangeUnsignedNumber, which would cause unnecessary overlap/re-processing (performance impact) when Vector512 is used.
Changes:
- Update the Vector512 loop to advance by
Vector512<T>.Countinstead ofVector256<T>.Count.
MihaZupan
approved these changes
Feb 1, 2026
Member
MihaZupan
left a comment
MihaZupan
left a comment
There was a problem hiding this comment.
Nice catch.
Does looks like the only effect is that we were throwing away half the throughput
tannergooding
approved these changes
Feb 1, 2026
This file contains hidden or 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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
I think this would only manifest as a perf rather than correctness issue.