Bug 251603 - Non-arm64e/x86 platforms load otherwise ignored tag arguments to call/jmp
Summary: Non-arm64e/x86 platforms load otherwise ignored tag arguments to call/jmp
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Angelos Oikonomopoulos
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2023-02-02 09:46 PST by Angelos Oikonomopoulos
Modified: 2023-02-16 03:37 PST (History)
1 user (show)

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Description Angelos Oikonomopoulos 2023-02-02 09:46:56 PST 
The extra arguments to call/jmp for pointer tagging are only used on arm64e (and are ignored during code generation on other platforms). However, on risc platforms, generic passes that convert large immediates to "load immediate into reg + use reg" sequences will pointlessly generate instructions to load any extra arguments into regs. This is dead code.
Comment 1 Angelos Oikonomopoulos 2023-02-02 09:54:10 PST 
Pull request: https://github.com/WebKit/WebKit/pull/9532
Comment 2 Radar WebKit Bug Importer 2023-02-09 09:47:44 PST 
<rdar://problem/105227555>
Comment 3 EWS 2023-02-16 03:37:46 PST 
Committed 260359@main (0faaa00680c0): <https://commits.webkit.org/260359@main>

Reviewed commits have been landed. Closing PR #9532 and removing active labels.