Bug 264041 - countTrailingZeros is redundant and slower than ctz
Summary: countTrailingZeros is redundant and slower than ctz
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Web Template Framework (show other bugs)
Version: WebKit Local Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2023-11-01 09:46 PDT by Seija K.
Modified: 2023-11-01 13:45 PDT (History)
1 user (show)

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Description Seija K. 2023-11-01 09:46:06 PDT 
In addition to being redundant because of ctz existing, the lookup table in itself is slower due to the operations happening to the variable v before retrieving the value. Source: https://godbolt.org/z/Pnd9nPPbo
Comment 1 EWS 2023-11-01 13:44:12 PDT 
Committed 270076@main (37c77f48561a): <https://commits.webkit.org/270076@main>

Reviewed commits have been landed. Closing PR #19840 and removing active labels.
Comment 2 Radar WebKit Bug Importer 2023-11-01 13:45:30 PDT 
<rdar://problem/117813174>