[FFmpeg-devel] [PATCH 6/6] lavc/ac3dsp: RISC-V B ac3_extract_exponents

[Rémi Denis-Courmont]

Le torstaina 15. kesäkuuta 2023, 13.36.45 EEST Peiting Shen a écrit :
> From: Shen Peiting <shenpeiting at eswincomputing.com>
> 
> Use RVB instruction clz to calculate the number of leading zeros of MSB
> instead of av_log2.
> 
> Benchmarks on Spike(cycles):
> ac3_extract_exponents_c: 8226
> ac3_extract_exponents_rvb: 1167

FWIW, RV-Zbb can be benchmarked on real hardware.

I would have done it already if only there was a checkasm case for this.

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