Refer to "checkasm: use perf API on Linux ARM*" commit for the
rationale.
The implementation is somehow duplicated with checkasm, but so is the
current usage of AV_READ_TIME(). Until these implementations and
heuristics are made consistent, I don't see a way of sharing that code.
Note: when using libavutil/timer.h, it is now important to include
before any other include due to the _GNU_SOURCE requirement.
The ISB (instruction synchronization barrier) might be too heavy for
START/STOPTIMER use but should be more accurate in checkasm where the
timing overhead is subtracted.
The new information is printed at verbose log level and can thus be switched on and off
through the log level
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Not guaranteed to be in nanosecond resolution. On iOS 7 the duration
of one tick is 125/3 ns which is still more than an order of magnitude
better then microseconds.
Replace decicycles with the neutral UNITS. Decicycles is strange but
tenths of a nanosecond and unspecific "deci"-ticks for mach_absolute_time
is just silly.
Passing an explicit filename to this command is only necessary if the
documentation in the @file block refers to a file different from the
one the block resides in.
Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk
Otherwise doxygen complains about ambiguous filenames when files exist
under the same name in different subdirectories.
Originally committed as revision 16912 to svn://svn.ffmpeg.org/ffmpeg/trunk