[FFmpeg-devel] FFMpeg on SH4 (STi7109)

Måns Rullgård mans
Wed Nov 19 01:54:55 CET 2008

"Jean-Michel Hautbois" <jhautbois at gmail.com> writes:

> 2008/11/18 Vitor Sessak <vitor1001 at gmail.com>
>> Hi
>> Jean-Michel Hautbois wrote:
>>> It runs, on the CPU. Now, the big work will start !
>> Nice. Does "make test" pass?
> I don't know, I will try next week I think (and hope).
>> The "right" way is to make the optimizations in qpel.c compile and work.
>> Did you try something in the line of the attached patch (completely
>> untested, I do not have a cross-compiler installed)?
> I tried something like that, an it didn't solve everything.
> I will go really further, inclunding QPel optimizations, before
> submitting anything.

I have fixed the code so it builds out of the box now.  It also works
to the extent qemu allows me to test it (qemu sh4 support is buggy).

Could I ask you to run some simple benchmarks with and without the
functions from qpel.c and dsputil_align.c?  I have the feeling those
optimisations are not all that optimal when all comes around.  A
comment in qpel.c talks about *p++ vs. p[n] to access arrays, and most
functions in this file seem to be the plain C functions rewritten to
use *p++ access.  There is, however, very little difference in the
generated code.

M?ns Rullg?rd
mans at mansr.com

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