1144361 - Enable jit code randomization on windows x64

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Tom S [:evilpie]]

Sad story, this was apparently disabled for a sunspider regression in bug 728623!
http://mxr.mozilla.org/mozilla-central/source/js/src/jit/ExecutableAllocatorWin.cpp#232

Comment 1

[(Away)]

Linking the bugs to create a path from that code comment to here.

Comment 2

[(Away)]

In quick testing I don't see the regression anymore. Definitely not the 2x slowdown seen in bug 728623. I tried both the current sunspider 1.0.2 and the 0.9.1 as originally filed. I guess 3 years can do a lot to the code!

I'm going to put up a patch and let the experts tell me what to scrutinize more closely.

Comment 3

[(Away)]

Attachment: Re-enable JIT code randomization on Win64

I just did a few local tests on the sunspider website. The overall score goes slightly down with this patch, but I think it's noise. In any case it's certainly not regressing.

What further testing should I do on this patch? Do you guys have local command line perf tests or things like that?

Comment 4

[Jan de Mooij [:jandem]]

Comment on attachment 8604904 [details] [diff] [review]
Re-enable JIT code randomization on Win64

Review of attachment 8604904 [details] [diff] [review]:
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Thanks!

The original sunspider regression is gone so we should just land this IMO.

Comment 5

[(Away)]

Ok, fair enough!

Comment 6

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/6d24046cb041

Comment 7

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/6d24046cb041