[OSSACanonicalizeOwned] Fix liveness passed to completion. #78624
nate-chandler
merged
7 commits into
swiftlang:main
from
nate-chandler:rdar142520491_2
[SIL] Print AST types with print-module-on-error.
9f87e0a8
[NFC] SILCombine: Ennamespace canonicalize class.
afe95135
[NFC] SILCombine: Extract processing function.
5ce6c6cf
[Test] Renamed test case.
6deba027
[Test] Added test for SILCombiner::processInst.
af5cd31f
[NFC] PrunedLiveness: Permit postDomBlocks dupes.
4135540f
nate-chandler157 days ago
Source compat failures match failures in baseline.
[OSSACanOwned] Fix liveness passed to completion.
ebf60280
nate-chandler156 days ago
@swift-ci please test
nate-chandler156 days ago
@swift-ci please apple silicon benchmark
nate-chandler156 days ago
@swift-ci please test source compatibility
nate-chandler156 days ago
@swift-ci please test macos platform
atrick
approved these changes
on 2025-01-15
atrick156 days ago
LGTM
Login to write a write a comment.
To determine where a lifetime ends within dead-end blocks,
OSSACanonicalizeOwnedusesOSSACompleteLifetime's visitAvailabilityBoundary. This API takes a liveness which it uses to walk forward to the availability boundary. Specifically, the liveness passed fromOSSACanonicalizeOwnedtoOSSACompleteLifetimeis a variation ofOSSACanonicalizeOwned's own liveness (it has destroys added).There is a mismatch in the characteristics of livenesses created by
OSSACanonicalizeOwnedandOSSACompleteLifetime: The former deals with not only direct uses of a value but also uses of its copies; that introduces the possibility for consuming uses in the middle of liveness. The latter on the other hand deals only with uses of a single value (nestedly, but at each level of nesting only a single value). Passing a liveness from the former to the latter without handling this mismatch is incorrect:OSSACompleteLifetimeunderstands consuming uses to always end a lifetime, even when they are in the middle of a copy-extended liveness. The result is thatOSSACompleteLifetimeproduces non-sensical results when provided with such a liveness.To address this, fixup the liveness passed from
OSSACanonicalizeOwnedtoOSSACompleteLifetimeby demoting consuming uses that appear within (that's to say not on the boundary) of liveness to non-consuming uses.Also, check in a few other changes that facilitated tracking this down:
-sil-print-module-on-errorSILCombineto extract the processing it does on a single instruction into a separate functionFunctionTestto call that newSILCombinefunctionrdar://142846936