[FFmpeg-devel] avfilter/x86/vf_blend : add avx2 version for 8b func (WIP)

[Martin Vignali]

2017-12-17 19:41 GMT+01:00 Henrik Gramner <henrik at gramner.com>:

> On Thu, Dec 14, 2017 at 11:16 AM, Martin Vignali
> <martin.vignali at gmail.com> wrote:
> > 2017-12-13 17:37 GMT+01:00 Henrik Gramner <henrik at gramner.com>:
> >> You could also do vextracti128 + 128-bit packuswb instead of 256-bit
> >> packuswb + vpermq.
> >>
> > Sorry don't understand this part
> > do you mean 128 bit packuswb + movh for each lane ?
> > or something else ?
>
> packuswb      m0, m0
> vpermq        m0, m0, q3120
>
> vs.
>
> vextracti128 xm1, m0, 1
> packuswb     xm0, xm1
>
> Uses a 128-bit op instead of a 256-bit one which is generally
> preferable whenever possible.
>
>
Thanks !
I will send a new patch, using this way.

Martin