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| author | Michael Niedermayer <michaelni@gmx.at> | 2006-03-31 16:50:43 +0000 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2006-03-31 16:50:43 +0000 |
| commit | ac2549b583f88d488326ad65b3d2f4539b1ae732 (patch) | |
| tree | c6bccfd06726acae26a227e492d33e38746a5bcc | |
| parent | 9296d45d29d0b747d54c824a7073cfbcb4cc7b96 (diff) | |
| download | ffmpeg-ac2549b583f88d488326ad65b3d2f4539b1ae732.tar.gz | |
avoid hard to predict branch (idea by arpi)
Originally committed as revision 5252 to svn://svn.ffmpeg.org/ffmpeg/trunk
| -rw-r--r-- | libavcodec/mjpeg.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/libavcodec/mjpeg.c b/libavcodec/mjpeg.c index 7a86482874..dbcbaed61d 100644 --- a/libavcodec/mjpeg.c +++ b/libavcodec/mjpeg.c @@ -1288,11 +1288,10 @@ static int decode_block(MJpegDecodeContext *s, DCTELEM *block, code &= 0xf; UPDATE_CACHE(re, &s->gb) - - if ((int32_t)GET_CACHE(re,&s->gb)<0) { //MSB=1 - level = NEG_USR32( GET_CACHE(re,&s->gb),code); - } else { - level = - NEG_USR32(~GET_CACHE(re,&s->gb),code); + { + int cache=GET_CACHE(re,gb); + int sign=(~cache)>>31; + level = (NEG_USR32(sign ^ cache,code) ^ sign) + (sign&1) ; } LAST_SKIP_BITS(re, &s->gb, code) |