On Thu, Nov 26, 2015 at 10:44 AM, Ganesh Ajjanagadde <gajjanaga...@gmail.com> wrote: > On Thu, Nov 26, 2015 at 10:37 AM, Ronald S. Bultje <rsbul...@gmail.com> wrote: >> Hi, >> >> On Thu, Nov 26, 2015 at 10:23 AM, Ganesh Ajjanagadde >> <gajjanaga...@gmail.com> wrote: >>> >>> This does some miscellaneous stuff mainly avoiding the usage of pow to >>> achieve significant speedups. This is not speed critical, but is >>> unnecessary latency and cycles wasted for a user. >>> >>> All tables tested and are identical to the old ones >>> (bit-exact even in floating point case). >>> >>> Sample benchmark (x86-64, Haswell, GNU/Linux): >>> old: >>> 102329530 decicycles in mpegaudio_tableinit, 1 runs, 0 skips >>> >>> new: >>> 34111900 decicycles in mpegaudio_tableinit, 1 runs, 0 skips >>> >>> Signed-off-by: Ganesh Ajjanagadde <gajjanaga...@gmail.com> >>> --- >>> libavcodec/mpegaudio_tablegen.h | 21 +++++++++++++++------ >>> 1 file changed, 15 insertions(+), 6 deletions(-) >>> >>> diff --git a/libavcodec/mpegaudio_tablegen.h >>> b/libavcodec/mpegaudio_tablegen.h >>> index 86b2cd3..6cd5ad6 100644 >>> --- a/libavcodec/mpegaudio_tablegen.h >>> +++ b/libavcodec/mpegaudio_tablegen.h >>> @@ -29,9 +29,11 @@ >>> >>> #define TABLE_4_3_SIZE (8191 + 16)*4 >>> #if CONFIG_HARDCODED_TABLES >>> +#include "libavutil/tablegen.h" >>> #define mpegaudio_tableinit() >>> #include "libavcodec/mpegaudio_tables.h" >>> #else >>> +#include "libavutil/libm.h" >> >> >> I don't think this works yet. Check mpegaudio_tablegen.c (it should be >> obvious why it does this): >> >> #include <stdlib.h> >> #define CONFIG_HARDCODED_TABLES 0 >> #include "mpegaudio_tablegen.h" >> #include "tableprint.h" >> >> Note that this is the table generation which runs on the host platform. So, >> the location where you add this, is important. I would recommend including >> tablegen.h inside mpegaudio_tablegen.c, and then including libavutil/libm.h >> outside the scope of this header, e.g. in users of this header, if >> tablegen.h wasn't included. Make sure make checkheaders passes after your >> changes, and the build works with as well as without hardcoded_tables. > > I did a build test with and without hardcoded , did not think of > checkheaders, will recheck and correct depending on the result.
checkheaders also passes with just this patch (both with or without hardcoded). Nevertheless, I agree with you and have now posted v3, tested with/without checkheaders and with/without --enable-hardcoded-tables. [...] > >> >> Ronald _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
