Commit Graph

9 Commits

Author SHA1 Message Date
James Almer
93e7b7fb34 avutil/x86/intmath: add missing check for inline assembly
Signed-off-by: James Almer <jamrial@gmail.com>
2015-06-27 14:33:53 -03:00
James Almer
1e51e517be avutil/x86/intmath: use bzhi gcc builtin in av_mod_uintp2()
Signed-off-by: James Almer <jamrial@gmail.com>
2015-06-27 12:56:55 -03:00
James Almer
60b9373dbd libavutil: add bmi2 optimized av_mod_uintp2
Reviewed-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: James Almer <jamrial@gmail.com>
2015-03-20 15:47:43 -03:00
James Almer
bc65abc8d7 libavutil: add x86 optimized av_popcount
Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2015-02-25 19:58:00 -03:00
Mans Rullgard
5b170c0bea x86: remove FASTDIV inline asm
GCC 4.3 and later do the right thing with the plain C code.  Earlier
versions in 32-bit mode generate one extra instruction, needlessly
zeroing what would be the high half of the shifted value.  At least
two gcc configurations miscompile the inline asm in some situations.

In 64-bit mode, all gcc versions generate imul r64, r64 followed by
shr.  On Intel i7 and later, this imul is faster 32-bit mul.  On
older Intel and all AMD, it is slightly slower.  On Atom it is much
slower.

Considering where the FASTDIV macro is used, any overall negative
performance impact of this change should be negligible.  If anyone
cares, they should file a bug against gcc and get the instruction
selection fixed.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-08-22 14:29:10 +01:00
Ronald S. Bultje
8123e0901f x86: place some inline asm under #if HAVE_INLINE_ASM
Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-06-25 13:23:12 +01:00
Mans Rullgard
2912e87a6c Replace FFmpeg with Libav in licence headers
Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-03-19 13:33:20 +00:00
Måns Rullgård
2ed6f39944 Replace many includes of libavutil/common.h with what is actually needed
This reduces the number of false dependencies on header files and
speeds up compilation.

Originally committed as revision 22407 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-03-09 17:39:19 +00:00
Måns Rullgård
75fb5c24ed Move FASTDIV macro to intmath.h
Originally committed as revision 21335 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-01-19 23:25:36 +00:00