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[doc] Atomic.add, .subtract: Add note on atomic codegen #78799

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Merged
merged 1 commit into from
May 17, 2025
Merged

[doc] Atomic.add, .subtract: Add note on atomic codegen #78799

merged 1 commit into from
May 17, 2025

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@lorentey lorentey commented Jan 22, 2025

Add this note to the doc string of Atomic.add and Atomic.subtract, highlighting a subtle aspect that tends to surprise folks who're porting code from C/C++:

The need to check for overflow means that this operation is typically compiled into a compare-exchange loop. For use cases that require a direct atomic addition, see the wrappingAdd operation: it avoids the loop, but in exchange it allows silent wraps on overflow.
@lorentey lorentey requested a review from Azoy January 22, 2025 00:02
@lorentey lorentey requested a review from a team as a code owner January 22, 2025 00:02
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lorentey commented Jan 22, 2025

@swift-ci test
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lorentey commented Jan 23, 2025

@swift-ci smoke test linux platform
@lorentey lorentey marked this pull request as draft January 23, 2025 17:49
@lorentey lorentey marked this pull request as ready for review February 1, 2025 02:15
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lorentey commented Feb 1, 2025

@swift-ci smoke test
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lorentey commented Apr 10, 2025

@swift-ci test linux platform
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lorentey commented Apr 28, 2025

@swift-ci test linux platform
@lorentey lorentey merged commit 02adf95 into swiftlang:main May 17, 2025
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@lorentey lorentey deleted the note-cas-loops branch May 17, 2025 02:05
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