Use @c instead of @_cdecl in the Embedded Swift runtime #85505
Merged
+138
−66
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
This eliminates a SIL verification error with `@c` functions, which provide definitions for foreign entrypoints. We were serializing @c definitions when we shouldn't be, which would cause problems down the line if those @c definitions referenced something internal that they shouldn't.
This change moves us toward the official feature, and eliminates the extra level of "thunk" that was implied by `@_cdecl`. Amusingly, this trips up the LLVM-level ARC optimizations, because we are trying to perform ARC optimizations within the retain/release runtime functions. Teach those optimization passes to leave swift_retainN et al alone.
DougGregor
requested review from
a team,
Xazax-hun,
egorzhdan,
hnrklssn,
j-hui,
jckarter and
susmonteiro
as code owners
Member
Author
|
@swift-ci please smoke test |
Contributor
|
Looks good |
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Outdated suggestions cannot be applied.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.
This change moves us toward the official feature, and eliminates the extra level of "thunk" that was implied by
@_cdecl. Amusingly, this trips up the LLVM-level ARC optimizations, because we are trying to perform ARC optimizations within the retain/release runtime functions. Teach those optimization passes to leave swift_retainN et al alone.Note that this also required a bug fix in our handling of
@cfunctions, where we would always serialize the SIL for them because they were being lumped in with foreign thunks.