827359 - WebRTC signal processing doesn't do runtime detection of NEON

Status: RESOLVED FIXED

(Core :: WebRTC, defect, P2)

Description

[Gian-Carlo Pascutto [:gcp]]

See https://bugzilla.mozilla.org/show_bug.cgi?id=812650#c6

This is because the current code is assuming ARMv7 always implies NEON. This is fixed upstream, so bug 818631 will fix it. 

A patch to disable NEON will work around the issue for now, but not sure what to think of taking the performance penalty - it only really breaks Tegra 2 devices, but those aren't exceptional.

Comment 1

[Gian-Carlo Pascutto [:gcp]]

Attachment: Patch 1. Disable NEON acceleration for now.

Comment 2

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 698746 [details] [diff] [review]
Patch 1. Disable NEON acceleration for now.

Review of attachment 698746 [details] [diff] [review]:
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Link it to the webrtc-updates bug so we know to look to back it out after we update

Comment 3

[Maire Reavy [:mreavy]]

Once we update the webrtc.org code, we will want to back this out.  Making webrtc-blocking+ and marking leave-open so we remember to back this out after our update.

Comment 4

[Gian-Carlo Pascutto [:gcp]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/1a8aaa10865d

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/1a8aaa10865d

Comment 6

[Randell Jesup [:jesup] (needinfo me)]

The current 3.20 merge patchset resolves this

Comment 7

[Nils Ohlmeier [:drno]]

I'm pretty sure the patch is no longer in our tree.