594126 - [TM+JM]Script time out on en.wikipedia.org

Status: RESOLVED DUPLICATE of bug 594108

(Core :: JavaScript Engine, defect)

Description

[Alice0775 White]

Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100907 Firefox/4.0b6pre ID:20100907044230

On the latest nightly of TraceMonkey build.

Alert message:
A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.

Script: http://bits.wikimedia.org/skins-1.5/common/jquery.min.js?283r:166

Reproducible: Always

Steps to Reproduce:
1. Start TM build with New profile
2. Open URL ( http://en.wikipedia.org/wiki/Mozilla )

Actual Results:
 Script timeout.

Regression window:
Works:
http://hg.mozilla.org/tracemonkey/rev/66c8ad02543b
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b5pre) Gecko/20100831 Firefox/4.0b5pre ID:20100901152948
Fails:
http://hg.mozilla.org/tracemonkey/rev/24749e6ae6e9
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b5pre) Gecko/20100901 Firefox/4.0b5pre ID:20100901175430
Pushlog;
http://hg.mozilla.org/tracemonkey/pushloghtml?fromchange=66c8ad02543b&tochange=24749e6ae6e9
Candidate:
Bug 581595 - Optimize creation of RegExp.prototype.exec's return value

Comment 1

[David Mandelin [:dmandelin]]

This is probably bug 594108.

Comment 2

[David Mandelin [:dmandelin]]

Attachment: Patch disabling optimization suspected of introducing the bug

I confirmed that disabling the optimization introduced in bug 581595 makes the problem go away.

Comment 3

[David Mandelin [:dmandelin]]

Duping over to bug 594108 as that one has the note saying this is blocking merging to m-c. Will continue work there.

Comment 4

[Alice0775 White]

WFM on the following TM hourly.
http://hg.mozilla.org/tracemonkey/rev/2bfe3a246736
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100907 Firefox/4.0b6pre ID:20100907192826

It also fixed the problem of Script timeout at http://journal.mycom.co.jp/ .