[AST] Stop using PointerIntPair for SIL params/results #32646
Merged
Conversation
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
The differentiability bit pushed the size of SILParameterInfo and SILResultInfo from 8 bytes to 16 bytes. Given that the low bits of the PointerIntPair are full and given that we do not want to over-align types, the PointerIntPair is not saving space anymore. Let's simplify these two data structures to make debugging easier (and the speed of debug builds slightly faster). In theory, release builds will also benefit due to fewer masking operations to extract the pointer or the low bits, but this will probably be "in the noise" for benchmarks. Note: this change is techinically not NFC because it fixes the SILResultInfo equality comparison function to check differentiability.
|
@swift-ci please smoke test |
|
It would be nice to have a |
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Outdated suggestions cannot be applied.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.
The differentiability bit pushed the size of SILParameterInfo and SILResultInfo from 8 bytes to 16 bytes. Given that the low bits of the PointerIntPair are full and given that we do not want to over-align types, the PointerIntPair is not saving space anymore. Let's simplify these two data structures to make debugging easier (and the speed of debug builds slightly faster). In theory, release builds will also benefit due to fewer masking operations to extract the pointer or the low bits, but this will probably be "in the noise" for benchmarks.
Note: this change is techinically not NFC because it fixes the SILResultInfo equality comparison function to check differentiability.