Bug 68723

Summary:

Resolve opcodes should have value profiling.

Product:

WebKit

Reporter:

Filip Pizlo <fpizlo>

Component:

JavaScriptCore

Assignee:

Nobody <webkit-unassigned>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

barraclough, fpizlo, oliver

Priority:

Version:

528+ (Nightly build)

Hardware:

All

OS:

All

Bug Depends on:

Bug Blocks:

68677

Attachments:

Description	Flags
the patch	oliver: review+

Description Filip Pizlo 2011-09-23 13:29:18 PDT

We want all operations that load values from the heap to have value profiling.  The Resolve opcodes are the last ones that don't.

Comment 1 Filip Pizlo 2011-09-23 15:27:13 PDT

Created attachment 108546 [details]
the patch

This is pretty much performance neutral.  There is a spurious, but totally reproducible, 0.3% slow-down in V8 on my MacBook Pro.  There are similarly sized, though not as reproducible, speed-ups in SunSpider and Kraken.  I checked and none of the benchmarks that have performance variations make any use of any of the affected opcodes.  So these are just insignificant variations due to code layout.

Comment 2 Filip Pizlo 2011-09-23 16:27:36 PDT

Landed in r95887.