Bug 242417

Summary:

Insert break instructions in the LLInt asm to ensure that some global labels are not aliased.

Product:

WebKit

Reporter:

Mark Lam <mark.lam>

Component:

JavaScriptCore

Assignee:

Mark Lam <mark.lam>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

ews-watchlist, keith_miller, msaboff, saam, tzagallo, webkit-bug-importer

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

Attachments:

Description	Flags
EWS testing.	none

Description Mark Lam 2022-07-06 19:44:47 PDT

This is needed because the linker may not handle aliased global labels (multiple global labels pointing to the same location) well.

To achieve this, we also remove the hacks in offlineasm's enterAsm and leaveAsm functions that use to add the _llintPCRangeStart and _llintPCRangeEnd labels.  Instead, we'll add them explicitly in LowLevelInterpreter.asm.  This allows us to easily append a break instruction after _llintPCRangeEnd.

Comment 1 Mark Lam 2022-07-06 19:45:18 PDT

<rdar://problem/94232529>

Comment 2 Mark Lam 2022-07-06 19:48:40 PDT

Created attachment 460728 [details]
EWS testing.

Comment 3 Mark Lam 2022-07-06 20:44:58 PDT

Pull request: https://github.com/WebKit/WebKit/pull/2149

Comment 4 EWS 2022-07-07 08:23:09 PDT

Committed 252214@main (98df1786d72c): <https://commits.webkit.org/252214@main>

Reviewed commits have been landed. Closing PR #2149 and removing active labels.