[FFmpeg-devel] [PATCH 1/3] riscv: add CPU flags for the RISC-V Vector extension

[Rémi Denis-Courmont]

Le lauantaina 3. syyskuuta 2022, 22.20.20 EEST Lynne a écrit :
> Sep 3, 2022, 21:01 by remi at remlab.net:
> > From: Rémi Denis-Courmont <remi at remlab.net>
> > 
> > RVV defines a total of 12 different extensions: V, Zvl32b, Zvl64b,
> > Zvl128b, Zvl256b, Zvl512b, Zvl1024b, Zve32x, Zve32f, Zve64x, Zve64f and
> > Zve64d.
> > 
> > At this stage, we don't care about the vector length extensions Zvl*,
> > as most or all optimisations will be running in a loop that is
> > independent on the data set size.
> 
> I need to know the maximum length to write an FFT.
> Could you add flags for it?

I think we should cross that bridge if/when the need actually arises. In most 
cases, the vector length returned at run-time from VSETVL is good enough.

-- 
雷米‧德尼-库尔蒙
http://www.remlab.net/