[FFmpeg-devel] [PATCH 2/4] lavc/mpegvideo: use H263DSP dequant function

Rémi Denis-Courmont remi at remlab.net
Fri Jun 14 22:03:00 EEST 2024


Le perjantaina 14. kesäkuuta 2024, 18.41.48 EEST James Almer a écrit :
> On 6/14/2024 12:11 PM, Rémi Denis-Courmont wrote:
> > Le perjantaina 14. kesäkuuta 2024, 17.45.50 EEST Rémi Denis-Courmont a 
écrit :
> >> And x86 only has MMX.
> > 
> > And the x86 code uses inline assembler. That's not viable on any ISA with
> > sane conventions such as Arm or RISC-V. The compiler will reject our
> > vector clobbers, unless the Vector extension is included in the
> > compilation target. But then that breaks run-time detection, and will be
> > rejected by all Linux distros.
> 
> I was thinking on removing that inline version and probably replacing it
> with sse2, using the dsp prototypes you introduce in this set.

I saw that, but we can't have the cake and eat it. Those DSP callbacks can't 
exist without adding a layer of indirection.

-- 
雷米‧德尼-库尔蒙
http://www.remlab.net/





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