[Ffmpeg-devel] Re: [PATCH] SIMD accelected SNOW decoding

Guillaume POIRIER poirierg
Wed Nov 30 23:24:52 CET 2005


On 11/28/05, Guillaume POIRIER <poirierg at gmail.com> wrote:
> commenting out _just_
> inner_add_yblock_mmx in snow.c gives me a grayish picture but no
> segfault.

Good, it looks like I managed to fix 'vertical_compose97i_asm': the
grayish picture is all gone now.

Please find in attachment the fixed files, which should be tested, if
possible, on IA-32 and AMD64.

Now I'm off to find a solution to fix 'inner_add_yblock_mmx' (which
still segfault when it executes the instruction 'movdqa
I suspected that the problem could be an unaligned memory access and
changed all movdqa to movdqu with no luck.

Then I had a closer look at the machine regs and it does look to me
that rdi being equal to 0xad73ba9000002aba (= -5948205555188225350)
couldn't be right.
I guess fixing the value given to rdi should do the trick.


Please do keep in mind that current version is work-in-progress: I'll
do my best to address Michael's comments when the SIMD code is fixed.

MPlayer's doc is offline. Find some fresh one here:
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