Do not eliminate casts from FP types when optimizing narrow stores#53667
Merged
kunalspathak merged 1 commit intoJul 13, 2021
Conversation
SingleAccretion
force-pushed
the
Fix-Potential-Issue-With-Cast-Elimination-For-Stores
branch
from
June 3, 2021 09:36
ff54d81 to
4dd49bb
Compare
SingleAccretion
marked this pull request as ready for review
June 3, 2021 14:47
An optimization in morph was deleting casts on the RHS of a narrow store if the cast-to-type was wider than the type being stored. This is only valid for casts from integral types, as the backend does not handle "STOREIND(byte*, double)", nor is there an instruction to go from an XMM register to a narrow memory location on x86/x64. The issue is not reproducible right now because fgMorphCast wraps the casts in question, but it is an invalid IR transformation nonetheless, and similar code in fgMorphSmpOpOptional guards against non-integral sources.
SingleAccretion
force-pushed
the
Fix-Potential-Issue-With-Cast-Elimination-For-Stores
branch
from
June 7, 2021 20:50
4dd49bb to
94de26a
Compare
Member
|
CC. @dotnet/jit-contrib, community PR |
Member
|
@kunalspathak @dotnet/jit-contrib PTAL community PR. |
Contributor
|
@SingleAccretion - No asmdiffs? |
Contributor
Author
Yes, no diffs as expected. |
SingleAccretion
deleted the
Fix-Potential-Issue-With-Cast-Elimination-For-Stores
branch
July 13, 2021 16:49
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 subscribe to this conversation on GitHub.
Already have an account?
Sign in.
4 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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
An optimization in morph was deleting casts on the RHS of a narrow store if the cast-to-type
was wider than the type being stored. This is only valid for casts from integral types, as the backend
does not handle
STOREIND(byte*, double), nor is there an instruction to go from anXMMregister to a narrow memory location on x86/x64.The issue is not reproducible right now because
fgMorphCastwraps the casts in question, but it is an invalid IR transformation nonetheless, and similar code infgMorphSmpOpOptionalguards against non-integral sources.Also, while I was there, modernized the code a little bit.