Bug 65212

Summary: DFG speculative JIT never emits inline double comparisons, even when it would be obvious more efficient to do so
Product: WebKit Reporter: Filip Pizlo <fpizlo>
Component: JavaScriptCoreAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: barraclough, fpizlo, webkit.review.bot
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Attachments:
Description Flags
the patch none

Filip Pizlo
Reported 2011-07-26 15:42:39 PDT
The DFG speculative JIT gets some of its performance improvement from treating certain numbers as doubles and never as ints. But comparisons don't take advantage of this, and instead either speculate integer, or perform slow C calls. The DFG speculative JIT's compare/branch implementations should inline double comparisons if it's obvious that this would be a win, for example if both operands are known to be double.
Attachments
the patch (9.47 KB, patch)
2011-07-26 15:47 PDT, Filip Pizlo 		no flags
DetailsFormatted DiffDiff
View All Add attachment proposed patch, testcase, etc.
Filip Pizlo
Comment 1 2011-07-26 15:47:45 PDT
Created attachment 102066 [details] the patch
WebKit Review Bot
Comment 2 2011-07-26 18:27:56 PDT
Comment on attachment 102066 [details] the patch Clearing flags on attachment: 102066 Committed r91807: <http://trac.webkit.org/changeset/91807>
WebKit Review Bot
Comment 3 2011-07-26 18:28:01 PDT
All reviewed patches have been landed. Closing bug.
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