1087496 - Optimize IsNullOrLikeUndefined(AndBranch)

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Jan de Mooij [:jandem]]

Attachment: Patch

These instructions currently emit two branches, to handle null and undefined. In many cases though we know the input can be null but not undefined, or vice versa, so we have to emit only one branch.

Octane-richards has some hot IsNullOrLikeUndefinedAndBranch tests, where we know the input is never undefined.

There's probably more room for improvement here but we can do that later.

Comment 1

[Hannes Verschore [:h4writer]]

Comment on attachment 8509691 [details] [diff] [review]
Patch

Review of attachment 8509691 [details] [diff] [review]:
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Nice!

Comment 2

[Jan de Mooij [:jandem]]

Thanks for the quick review!

https://hg.mozilla.org/integration/mozilla-inbound/rev/1220cafa6058

Comment 3

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

https://hg.mozilla.org/mozilla-central/rev/1220cafa6058