Bug 225983

Summary: Ripping out broken Baseline JIT rare case profiling.
Product: WebKit Reporter: Mark Lam <mark.lam>
Component: JavaScriptCoreAssignee: Mark Lam <mark.lam>
Status: RESOLVED FIXED    
Severity: Normal CC: ews-watchlist, keith_miller, msaboff, rmorisset, saam, tzagallo, webkit-bug-importer, ysuzuki
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
proposed patch. saam: review+

Description Mark Lam 2021-05-19 14:30:10 PDT 
The profiling has been broken in recent times.  Fixing it to work does not appear to improve performance.  Ripping out the profiling appears to not hurt performance.  However, ripping out the profiling appears to save on code size generated for the Baseline JIT.
Comment 1 Mark Lam 2021-05-19 14:47:38 PDT 
Created attachment 429098 [details]
proposed patch.
Comment 2 Yusuke Suzuki 2021-05-19 14:55:19 PDT 
*** Bug 224618 has been marked as a duplicate of this bug. ***
Comment 3 Robin Morisset 2021-05-19 14:55:38 PDT 
Comment on attachment 429098 [details]
proposed patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=429098&action=review

r=me too

> Source/JavaScriptCore/ChangeLog:9
> +        to improve performance.  Ripping out the profiling appears to not hurt performance.

Can you mention in the Changelog what performance test you ran to verify this (JetStream2? Speedometer?)?.
Comment 4 Mark Lam 2021-05-19 15:30:57 PDT 
Thanks for the reviews.  Landed in r277758: <http://trac.webkit.org/r277758>.
Comment 5 Radar WebKit Bug Importer 2021-05-19 15:31:18 PDT 
<rdar://problem/78227853>