Bug 154828 - B3::fixSSA() has problems in Octane/regexp
Summary: B3::fixSSA() has problems in Octane/regexp
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: All All
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks: 154319
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Reported: 2016-02-29 11:41 PST by Filip Pizlo
Modified: 2019-06-09 19:20 PDT (History)
1 user (show)

See Also:

Attachments
fixSSA going nuts according to Instruments (493.21 KB, image/png)
2016-02-29 11:46 PST, Filip Pizlo 		no flags Details
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Description Filip Pizlo 2016-02-29 11:41:50 PST 
Usually you know that everything is OK when the compiler spends 95% of its time in IRC.  But in Octane/regexp, this is not the case!  We spent lots of time in fixSSA() instead.  That usually means a scalability problem in that phase.

I've known for a while now that our SSA conversion has scalability problems, and it looks like we're now seeing this.

Note: I don't think that this is actually bottlenecking Octane/regexp performance.  So it's not a high priority right now.
Comment 1 Filip Pizlo 2016-02-29 11:46:23 PST 
Created attachment 272507 [details]
fixSSA going nuts according to Instruments