Bug 150688

Summary:

Air::handleCalleeSaves shouldn't save/restore the frame pointer

Product:

WebKit

Reporter:

Filip Pizlo <fpizlo>

Component:

JavaScriptCore

Assignee:

Filip Pizlo <fpizlo>

Status:

RESOLVED FIXED

Severity:

Normal

Priority:

Version:

WebKit Nightly Build

Hardware:

All

OS:

All

Bug Depends on:

Bug Blocks:

150279

Attachments:

Description	Flags
the patch	msaboff: review+

Description Filip Pizlo 2015-10-29 13:01:26 PDT

Patch forthcoming.

Comment 1 Filip Pizlo 2015-10-29 16:55:03 PDT

Created attachment 264366 [details]
the patch

Comment 2 Saam Barati 2015-10-29 17:27:31 PDT

Comment on attachment 264366 [details]
the patch

r=me

Comment 3 Michael Saboff 2015-10-29 17:31:40 PDT

Comment on attachment 264366 [details]
the patch

View in context: https://bugs.webkit.org/attachment.cgi?id=264366&action=review

r-

> Source/JavaScriptCore/b3/air/AirHandleCalleeSaves.cpp:55
>      usedCalleeSaves.filter(RegisterSet::calleeSaveRegisters());
> +    usedCalleeSaves.exclude(RegisterSet::stackRegisters()); // We don't need to save FP here.

RegisterSet::calleeSaveRegisters() already contains the frame pointer.  In all cases, it uses the native register name.

Comment 4 Michael Saboff 2015-10-29 17:33:38 PDT

Comment on attachment 264366 [details]
the patch

View in context: https://bugs.webkit.org/attachment.cgi?id=264366&action=review

r+

>> Source/JavaScriptCore/b3/air/AirHandleCalleeSaves.cpp:55
>>      usedCalleeSaves.filter(RegisterSet::calleeSaveRegisters());
>> +    usedCalleeSaves.exclude(RegisterSet::stackRegisters()); // We don't need to save FP here.
> 
> RegisterSet::calleeSaveRegisters() already contains the frame pointer.  In all cases, it uses the native register name.

Sorry, didn't see the .filter for RegisterSet::calleeSaveRegisters().

Comment 5 Filip Pizlo 2015-10-29 18:47:20 PDT

Landed in http://trac.webkit.org/changeset/191771