Bug 141632 - Rare case profiling should actually work
Summary: Rare case profiling should actually work
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: 528+ (Nightly build)
Hardware: All All
: P2 Normal
Assignee: Filip Pizlo
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2015-02-15 21:18 PST by Filip Pizlo
Modified: 2015-02-15 22:19 PST (History)
0 users

See Also:

Attachments
the patch (1.83 KB, patch)
2015-02-15 22:13 PST, Filip Pizlo 		msaboff: review+
Details | Formatted Diff | Diff
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Description Filip Pizlo 2015-02-15 21:18:46 PST 
Currently, the "likelyToTakeSlowCaseMinimumCount" threshold is 100, which is larger than the number of times a typical bytecode instruction will execute before being DFG compiled (that threshold averages around 1000/15 ~ 66).  This means that the rare case profiling doesn't actually help us avoid overspeculating.
Comment 1 Filip Pizlo 2015-02-15 22:13:35 PST 
Created attachment 246634 [details]
the patch
Comment 2 Michael Saboff 2015-02-15 22:15:22 PST 
Comment on attachment 246634 [details]
the patch

r=me
Comment 3 Filip Pizlo 2015-02-15 22:19:45 PST 
Landed in http://trac.webkit.org/changeset/180137