avfilter,swresample,swscale: use fabs, fabsf instead of FFABS

It is well known that fabs and fabsf are at least as fast and sometimes
faster than the FFABS macro, at least on the gcc+glibc combination.
For instance, see the reference:
http://patchwork.sourceware.org/patch/6735/.
This was a patch to glibc in order to remove their usages of a macro.

The reason essentially boils down to fabs using the __builtin_fabs of
the compiler, while FFABS needs to infer to not use a branch and to
simply change the sign bit. Usually the inference works, but sometimes
it does not. This may be easily checked by looking at the asm.

This also has the added benefit of reducing macro usage, which has
problems with side-effects.

Note that avcodec is not handled here, as it is huge and
most things there are integer arithmetic anyway.

Tested with FATE.

Reviewed-by: Clément Bœsch <u@pkh.me>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/libavfilter/vf_framerate.c b/libavfilter/vf_framerate.c
index e8fba285d8..237a4873b3 100644
--- a/libavfilter/vf_framerate.c
+++ b/libavfilter/vf_framerate.c
@@ -223,7 +223,7 @@ static int blend_frames16(AVFilterContext *ctx, float interpolate,
     }
     // decide if the shot-change detection allows us to blend two frames
     if (interpolate_scene_score < s->scene_score && copy_src2) {
-        uint16_t src2_factor = FFABS(interpolate) * (1 << (s->bitdepth - 8));
+        uint16_t src2_factor = fabsf(interpolate) * (1 << (s->bitdepth - 8));
         uint16_t src1_factor = s->max - src2_factor;
         const int half = s->max / 2;
         const int uv = (s->max + 1) * half;
@@ -287,7 +287,7 @@ static int blend_frames8(AVFilterContext *ctx, float interpolate,
     }
     // decide if the shot-change detection allows us to blend two frames
     if (interpolate_scene_score < s->scene_score && copy_src2) {
-        uint16_t src2_factor = FFABS(interpolate);
+        uint16_t src2_factor = fabsf(interpolate);
         uint16_t src1_factor = 256 - src2_factor;
         int plane, line, pixel;