Unlike x86, fmin/fmax are single instructions, not function calls. They are much much faster than doing a comparison, then branching based on its results. With this, audiodsp.vector_clipf gets almost twice as fast, and a properly unrollled version of it gets 4-5x faster, on SiFive-U74. This is only the low-hanging fruit: FFMIN and FFMAX are presumably affected as well.
This likely applies to other instruction sets with native IEEE floats, especially those lacking a conditional select instruction. --- libavutil/riscv/intmath.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/libavutil/riscv/intmath.h b/libavutil/riscv/intmath.h index 3e7ab864c5..24f165eef1 100644 --- a/libavutil/riscv/intmath.h +++ b/libavutil/riscv/intmath.h @@ -22,6 +22,7 @@ #define AVUTIL_RISCV_INTMATH_H #include <stdint.h> +#include <math.h> #include "config.h" #include "libavutil/attributes.h" @@ -72,6 +73,24 @@ static av_always_inline av_const int av_clip_intp2_rvi(int a, int p) return b; } +#if defined (__riscv_f) || defined (__riscv_zfinx) +#define av_clipf av_clipf_rvf +static av_always_inline av_const float av_clipf_rvf(float a, float min, + float max) +{ + return fminf(fmaxf(a, min), max); +} +#endif + +#if defined (__riscv_d) || defined (__riscv_zdinx) +#define av_clipd av_clipd_rvd +static av_always_inline av_const float av_clipd_rvd(double a, double min, + double max) +{ + return fmin(fmax(a, min), max); +} +#endif + #if defined (__GNUC__) || defined (__clang__) static inline av_const int ff_ctz_rv(int x) { -- 2.45.2 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".