[FFmpeg-devel] [PATCH] avcodec/utvideodec: use cached bitstream reader only on targets with fast 64bit ops

James Almer jamrial at gmail.com
Sun Sep 2 20:46:33 EEST 2018

On 9/2/2018 5:30 AM, Carl Eugen Hoyos wrote:
>> Am 02.09.2018 um 01:18 schrieb James Almer <jamrial at gmail.com>:
>> Signed-off-by: James Almer <jamrial at gmail.com>
>> ---
>> Unbenched, but if x86_32 is slow with it, then chances are so are arm
>> and similar 32bit architectures.
> Please do not commit without benchmarks, I found no other architecture where the new reader is slower.

I can't bench on anything but x86, which is why i sent this patch to get
other people's opinions.

You tried other 32 bit architectures like arm7 or PPC? fast_64 is a
configure time constant used in a lot of speed critical modules to
choose between using 32bit or 64bit ops, so seeing how this new
bitstream reader uses a 64bit cache I'd expect it to be slower in such
targets as well.

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