1024678 - Avoid using xmm registers in regexp code

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Brian Hackett [Laid off!]]

Attachment: patch

Floating point registers can't be accessed if the JIT does not support them.  While irregexp never accesses these registers, when external calls are made all volatile registers are pushed, including these registers.

Comment 1

[Brian Hackett [Laid off!]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/7a079e370c33

Comment 2

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

https://hg.mozilla.org/mozilla-central/rev/7a079e370c33

Comment 3

[Ken]

Is this fix going to be pushed down to Aurora 32.0a2?

It looks like crashes I had in Nightly 32.0a1 [involving js::irregexp (e.g. bug #1013586), which were fixed with this patch (Bug) landing], are now occurring in Aurora 32.0a2.

Or, is there a different bug# I should follow for this fix being applied to Aurora?

Comment 4

[Brian Hackett [Laid off!]]

Comment on attachment 8439426 [details] [diff] [review]
patch

[Approval Request Comment]
Bug caused by (feature/regressing bug #): bug 976446
User impact if declined: crashes on older CPUs
Testing completed (on m-c, etc.): on m-c
Risk to taking this patch (and alternatives if risky): none

Comment 5

[Lukas Blakk [:lsblakk] use ?needinfo]

Comment on attachment 8439426 [details] [diff] [review]
patch

Not serious enough to track, but uplift is low risk and helps with crashes so approving.

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-aurora/rev/b10a750d205d