Changeset cb93df0d in ffmpeg

Timestamp:
Dec 9, 2015, 12:36:58 PM (9 years ago)
Author:
Ganesh Ajjanagadde <gajjanagadde@gmail.com>
Branches:
master
Children:
00c32201
Parents:
e74f1a12
git-author:
Ganesh Ajjanagadde <gajjanagadde@gmail.com> (11/30/15 03:35:00)
git-committer:
Ganesh Ajjanagadde <gajjanagadde@gmail.com> (12/09/15 12:36:58)
Message:

avcodec/aacsbr_tablegen: always initialize tables at runtime

This gets rid of virtually useless hardcoded tables hackery. The reason
it is useless is that a 320 element lut is anyway placed regardless of
--enable-hardcoded-tables, from which all necessary tables are trivially
derived at runtime at very low cost:

sample benchmark (x86-64, Haswell, GNU/Linux, single run is really
what is relevant here since looping drastically changes the bench). Fluctuations
are on the order of 10% for the single run test:
39400 decicycles in aacsbr_tableinit, 1 runs, 0 skips
25325 decicycles in aacsbr_tableinit, 2 runs, 0 skips
18475 decicycles in aacsbr_tableinit, 4 runs, 0 skips
15008 decicycles in aacsbr_tableinit, 8 runs, 0 skips
13016 decicycles in aacsbr_tableinit, 16 runs, 0 skips
12005 decicycles in aacsbr_tableinit, 32 runs, 0 skips
11546 decicycles in aacsbr_tableinit, 64 runs, 0 skips
11506 decicycles in aacsbr_tableinit, 128 runs, 0 skips
11500 decicycles in aacsbr_tableinit, 256 runs, 0 skips
11183 decicycles in aacsbr_tableinit, 509 runs, 3 skips

Tested with FATE with/without --enable-hardcoded-tables.

Reviewed-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

(No files)

Note: See TracChangeset for help on using the changeset viewer.