4-operation form is preferred over 3-operation because it breaks a long
dependency chain, thus allowing a superscalar processor to execute more
operations in parallel.
The idea was taken from: http://www.zorinaq.com/papers/md5-amd64.html
AMD Athlon(tm) II X3 450 Processor, x86_64
$ for i in $(seq 1 4); do ./avutil_md5_test2; done
size: 1048576 runs: 1024 time: 5.821 +- 0.019
size: 1048576 runs: 1024 time: 5.822 +- 0.019
size: 1048576 runs: 1024 time: 5.841 +- 0.018
size: 1048576 runs: 1024 time: 5.821 +- 0.018
$ for i in $(seq 1 4); do ./avutil_md5_test2; done
size: 1048576 runs: 1024 time: 5.646 +- 0.019
size: 1048576 runs: 1024 time: 5.646 +- 0.018
size: 1048576 runs: 1024 time: 5.642 +- 0.019
size: 1048576 runs: 1024 time: 5.641 +- 0.019
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Allows decoding with only three frame buffers with frame reference
counting. Fixes VAAPI based decoding in vlc which uses only three
frame buffers for the mpegvideo-based codecs.
The use of ff_inverse speeds up slightly arches + compilers that
do not provide a division faster than the whole machinery, such
as ppc32 + gcc4.7, but has operational limits.
Drop the always-enable assert and provide a fallback.
MSVC 2010 (or more precisely, Windows SDK 7.0 which comes with MSVC
2010) sets _WIN32_WINNT to the constant for Windows 7 if nothing is
set. This could lead to the libav configure script detecting and
using functions only present in Windows 7 or newer, which in most
cases isn't desired. If the caller explicitly wants this, the caller
can add the _WIN32_WINNT define via --extra-cflags, setting the desired
version.
Signed-off-by: Martin Storsjö <martin@martin.st>
* commit '8e673efc6f5b7a095557664660305148f2788d30':
prores: update FATE test to account for alpha plane present in the test sample
configure: Add basic valgrind-massif support
Conflicts:
tests/fate/prores.mak
tests/ref/fate/prores-alpha
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Both strtoll and atoll have different names on MSVC, and strtoll has a
compatibility layer in place for this case.
Fixes compilation on MSVC.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
With the parameter --toolchain valgrind-massif, the configure
script sets reasonable defaults that can be overridden as explained
in the documentation.
Fixes crash on SSE2
Fixes Ticket2443
Note, its possible to restructure the code to avoid the 16pixel limitation,
and such change is welcome!
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
It was previously declared as int.
Does not change fate results for x86.
Conflicts:
libavcodec/ppc/fmtconvert_altivec.c
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
