Le lauantaina 6. heinäkuuta 2024, 18.23.00 EEST Andreas Rheinhardt a écrit :
> > static void dct_unquantize_h263_inter_c(MpegEncContext *s,
> >
> > int16_t *block, int n, int qscale)
> >
> > {
> >
> > - int i, level, qmul, qadd;
> > + int qmul = qscale << 1;
> > + int qadd = (qscale - 1) | 1;
> >
> > int nCoeffs;
> >
> > av_assert2(s->block_last_index[n]>=0);
> >
> > - qadd = (qscale - 1) | 1;
> > - qmul = qscale << 1;
> > -
> >
> > nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
> >
> > -
> > - for(i=0; i<=nCoeffs; i++) {
> > - level = block[i];
> > - if (level) {
> > - if (level < 0) {
> > - level = level * qmul - qadd;
> > - } else {
> > - level = level * qmul + qadd;
> > - }
> > - block[i] = level;
> > - }
> > - }
> > + s->h263dsp.h263_dct_unquantize_inter(block, nCoeffs, qmul, qadd);
>
> This adds an indirection. I have asked you to actually benchmark this
> code (and not only the DSP function you add), but you never did.
I already pointed out previously that this is the way this project does DSP
code. Certainly it would be nice to hard-code the path when there is only one
possible. This is often the case on Armv8 notably, and of course on platforms
without optimisations.
But that's a general problem way beyond the scope of this patchset. We always
add indirect function calls in this sort of situation, and I don't see why I
would have duty to benchmark it, so I am going to ignore this.
--
雷米‧德尼-库尔蒙
http://www.remlab.net/
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