Bug 185151 - B3::demoteValues should be able to handle patchpoint terminals
Summary: B3::demoteValues should be able to handle patchpoint terminals
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: All All
: P2 Normal
Assignee: Filip Pizlo
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2018-04-30 17:50 PDT by Filip Pizlo
Modified: 2018-05-01 12:57 PDT (History)
6 users (show)

See Also:

Attachments
the patch (12.14 KB, patch)
2018-04-30 17:59 PDT, Filip Pizlo 		saam: review+
Details | Formatted Diff | Diff
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Description Filip Pizlo 2018-04-30 17:50:22 PDT 
Patch forthcoming.
Comment 1 Filip Pizlo 2018-04-30 17:59:58 PDT 
Created attachment 339168 [details]
the patch
Comment 2 Saam Barati 2018-04-30 18:14:06 PDT 
Comment on attachment 339168 [details]
the patch

View in context: https://bugs.webkit.org/attachment.cgi?id=339168&action=review

r=me

> Source/JavaScriptCore/b3/B3BreakCriticalEdges.cpp:44
> +        // Non-void terminals that are the moral equivalent of jumps trigger critical edge braking
> +        // because of fixSSA's demoteValues.

"of jumps trigger" => "of jumps that trigger"
"braking" => "breaking"

I would also say instead of "because of fixSSA's demote values" something like "fixSSA's demote values relies on this invariant"

> Source/JavaScriptCore/b3/B3FixSSA.cpp:306
> +            if (variable) {

I think some comment saying this is for terminal patchpoints that are non void might make whoever reads this code in ~6months happier.
Comment 3 Filip Pizlo 2018-05-01 12:56:14 PDT 
Landed in https://trac.webkit.org/changeset/231204/webkit
Comment 4 Radar WebKit Bug Importer 2018-05-01 12:57:25 PDT 
<rdar://problem/39875383>