[FFmpeg-devel] [PATCH v4 1/9] lavc/vp8dsp: R-V put_vp8_pixels

[Rémi Denis-Courmont]

Le tiistaina 7. toukokuuta 2024, 20.41.30 EEST Lynne a écrit :
> May 7, 2024, 18:54 by uk7b at foxmail.com:
> > From: sunyuechi <sunyuechi at iscas.ac.cn>
> > 
> > C908:
> > vp8_put_pixels4_c: 78.0
> > vp8_put_pixels4_rvi: 33.7
> > vp8_put_pixels8_c: 278.0
> > vp8_put_pixels8_rvi: 55.0
> > vp8_put_pixels16_c: 999.0
> > vp8_put_pixels16_rvi: 86.7
> > ---
> > 
> >  libavcodec/riscv/Makefile      |  1 +
> >  libavcodec/riscv/vp8dsp.h      | 75 ++++++++++++++++++++++++++++++++++
> >  libavcodec/riscv/vp8dsp_init.c | 22 ++++++++++
> >  libavcodec/riscv/vp8dsp_rvi.S  | 61 +++++++++++++++++++++++++++
> >  libavcodec/vp8dsp.c            |  2 +
> >  libavcodec/vp8dsp.h            |  1 +
> >  6 files changed, 162 insertions(+)
> >  create mode 100644 libavcodec/riscv/vp8dsp.h
> >  create mode 100644 libavcodec/riscv/vp8dsp_rvi.S
> > 
> > +
> > +av_cold void ff_vp78dsp_init_riscv(VP8DSPContext *c)
> > +{
> > +#if HAVE_RV
> > +    int flags = av_get_cpu_flags();
> > +    if (flags & AV_CPU_FLAG_RVI) {
> > +#if __riscv_xlen >= 64
> 
> Why are you not detecting this at runtime?

XLEN is a compile time constant of the ABI. You cannot run 32-bit code in 64-
bit mode, and the ELF loader will not allow you to do so.

-- 
Rémi Denis-Courmont
http://www.remlab.net/