libvpx crashes when using VP8_COPY_REFERENCE and VP8_SET_REFERENCE on iOS neon builds

[GoogleCodeExporter]

What is the expected behavior? What do you see instead?
Lib crashes in vp8_vpxyv12_extendframeborders_neon.asm.s with bad access (line 
218 vst1.8          {q8, q9}, [r6]!).

What version are you using? On what operating system?
Version: latest drop from git repo.
OS: iOS with enabled neon (without neon it works ok)

Can you reproduce using the vpxdec or vpxenc tools? What command line are
you using?

I am using custom code that encodes video with only one reference frame (first 
frame) and all other frames are delta frames. On client side i'm setting again 
reference frame when decoding. I'm doing this because I need fast frame seek.

Please provide any additional information below.

Original issue reported on code.google.com by romih.ma...@gmail.com on 13 Feb 2013 at 9:36

[GoogleCodeExporter]

Basically the crash occurs when I call

(vpx_codec_control(&codec, VP8_COPY_REFERENCE, refLast))

but this happens only when I use armv7 build with neon support

Original comment by romih.ma...@gmail.com on 14 Feb 2013 at 9:17

[GoogleCodeExporter]

Original comment by jkoles...@google.com on 14 Mar 2013 at 10:08

• Changed state: Assigned

[GoogleCodeExporter]

Can you provide any more details? Frame resolution? If you could provide sample 
input that would be ideal.

Does this occur during encode or decode? If encode, all options. If decode, 
just an output stream. Generating an IVF file is quite easy. See 
simple_encoder.c (it is generated when you enable the examples).

Original comment by johannkoenig@google.com on 14 Mar 2013 at 10:25

[GoogleCodeExporter]

It happens when decoding and only if I try to decode bigger frames (it
works with some artifacts on smaller 480x320px resolution but it fails on
960x640px).

Because I have video with very similar frames I'm using custom encoder that
sets reference frame to the first frame of the video and for every other
frame (this way all other frames are delta frames).

The decoder is also adjusted so that it is using first frame as the
reference when decoding.

But the issue is not how video is encoded/decoded because when I use normal
non NEON build it works fine but when I use NEON build it fails on bigger
frame sizes and has some weird artifacts on smaller frame sizes.

Original comment by romih.ma...@gmail.com on 17 Mar 2013 at 11:07

[GoogleCodeExporter]

If you use an unmodified decoder do you get the same crash? Can you send me 
files which cause the artifacts/crashes?

Original comment by johannkoenig@google.com on 18 Mar 2013 at 6:33

[GoogleCodeExporter]

Please reopen if this is still an issue.

Original comment by johannkoenig@google.com on 6 Nov 2014 at 1:28

• Changed state: WontFix