JitArm64: Skip checking last input for NaN for non-SIMD operations #12092
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
JosJuice
force-pushed
the
jitarm64-last-nan
branch
from
56e4cb2
to
a12b54c
Compare
|
Needs a rebase |
AArch64's handling of NaNs in arithmetic instructions matches PowerPC's as long as no more than one of the operands is NaN. If we know that all inputs except the last input are non-NaN, we can therefore skip checking the last input. This is an optimization that in principle only works for non-SIMD operations, but ps_sumX effectively is non-SIMD as far as the arithmetic part of it is concerned, so we can use it there too.
So short that using farcode is pointless!
JosJuice
force-pushed
the
jitarm64-last-nan
branch
from
a12b54c
to
fc95d59
Compare
lioncash
approved these changes
Nov 28, 2023
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Outdated suggestions cannot be applied.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.
AArch64's handling of NaNs in arithmetic instructions matches PowerPC's as long as no more than one of the operands is NaN. If we know that all inputs except the last input are non-NaN, we can therefore skip checking the last input. This is an optimization that in principle only works for non-SIMD operations, but ps_sumX effectively is non-SIMD as far as the arithmetic part of it is concerned, so we can use it there too.