Bug 268421

Summary:	Avoid using x18 in WTF/libPAS assertions
Product:	WebKit	Reporter:	David Degazio <d_degazio>
Component:	Web Template Framework	Assignee:	David Degazio <d_degazio>
Status:	RESOLVED FIXED
Severity:	Normal	CC:	doremylover123, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description David Degazio 2024-01-30 16:19:01 PST

rdar://121969027

When we fail a libPAS or WTF assertion, we write the reason and some associated data to specific registers so they show up in thread dumps or can be queried easily in debuggers. Currently, however, we naively pick the registers x16 through x22 on ARM64 targets, which includes the reserved platform register x18. Even if it's only on crash, we should avoid modifying this register to play nicely with any environments or operating system features that depend on this register for their own internal use.

Comment 1 David Degazio 2024-01-30 17:21:49 PST

Pull request: https://github.com/WebKit/WebKit/pull/23552

Comment 2 Ahmad Saleem 2024-01-30 19:39:23 PST

*** Bug 258033 has been marked as a duplicate of this bug. ***

Comment 3 EWS 2024-01-31 10:00:06 PST

Committed 273835@main (0806bfc07433): <https://commits.webkit.org/273835@main>

Reviewed commits have been landed. Closing PR #23552 and removing active labels.