00d1f50eff introduced a regression for PPC
since the `signal()` based detection for altivec in libmpeg2 is not thread
safe unlike our own. here we restore use of our own detection for PPC,
bypassing libmpeg2's unsafe auto-detection otherwise triggered in
`mpeg2_init()`.
fixes#25948.
in the qt codebase properties are often used but they are not
overridden by a derived class.
according to the Qt docs, the presence of final attribute can
be used for performance optimizations.
../../modules/demux/adaptive/logic/BufferingLogic.cpp: In member function ‘uint64_t adaptive::logic::DefaultBufferingLogic::getLiveStartSegmentNumber(adaptive::playlist::BaseRepresentation*) const’:
../../modules/demux/adaptive/logic/BufferingLogic.cpp:363:30: warning: ‘this’ pointer is null [-Wnonnull]
363 | if(!timeline->isValid())
| ~~~~~~~~~~~~~~~~~^~
Typo from 573752cfad
this:
- enables SSE2 (when available at runtime), which was added 13 years ago
([1]) but we never enabled use of it until now.
- removes use of the MMX/MMXEXT availability testing functions, helping
pave the way towards our goal of purging all MMX/MMXEXT code.
- makes the code cleaner and reduces maintenance burden.
- allows us to pick up use of new SIMD variant additions, if any more are
ever added (unlikely) without having to explicitly add code to enable it.
as pointed out in review, the `mpeg2_init()` call makes a call to
`mpeg2_accel()` with `MPEG2_ACCEL_DETECT` itself, so there is no need to
make such a call ourselves, thus the `mpeg2_init()` call alone is
sufficient. the entire code block can thus be safely removed.
[1]: c80d1dc2f1
new "auto" color scheme automatically switches between "day" and
"night" color scheme based on system settings
available color schemes -
on windows: auto, day, night
other: system, day, night
Closes#25590
a call made to `x264_param_default[_mpeg2]()` triggers cpu feature
detection built into the x262/x264 lib, setting up the default value of the
cpu flags 'param' attribute. the block of code deleted here pointlessly
tried to subsequently remove a certain subset of flags from this where the
vlc detection found those features to not be available.
this dates back to before VLC v1.2 when we had core options that gave users
a means of disabling use of individual SIMD variants - this block of code
would apply such user choices to the use of the x262/x264 lib.
those options were removed in 1081b213dc for
v1.2, but blocks of code like this were left behind. some adjustments to
the cpu detection code were done for v1.3, which touched these code blocks,
but seems to not have involved evaluating their necessity.
without those old options, this block of code is utterly pointless,
achieving nothing.
Lyndon Brown