This improves performance pretty much across the board for games.
The increase in performance is mainly from removing some code from the main JIT blocks of code (pushing and popping millions of registers) and
throwing them in farcode where it doesn't pollute the icache.
This is required to make sure two code spaces are relatively close to one another.
In this case I need the AArch64 JIT codespace and its farcode space to be within 128MB of one another for branches.
When the emulation is paused and the ALSA backend is used, make the audio
thread wait on a condition variable instead of busy-waiting. This commit
fixes bug #7729
Since the ALSA API is not thread-safe, calls to snd_pcm_drop() and snd_pcm_prepare()
in AlsaSound::Clear() are protected by the same mutex as the condition variable in AlsaSound::SoundLoop()
to make sure that we do not call these functions while a call to
snd_pcm_writei() is ongoing.
This fixes a race condition:
Before this commit, there was a race condition when starting a game:
Core::EmuThread(), after having started (but not necessarily completed)
the initialization of the audio thread, calls Core::SetState() which calls
CCPU::EnableStepping(), which in turns calls AudioCommon::ClearAudioBuffer().
This means that SoundStream::Clear() can be called before
AlsaSound::AlsaInit() has completed.
If the selected audio backend fails to Start() (which could happen for
example if there is no audio device), we currently still use the backend
anyway. This can lead to crashes on some platforms (such as Windows) and
is outright wrong anyway.
This commit fallbacks to the Null audio backend if the selected backend
couldn't be started.
This fixes bug #6001
For some dumb reason, llvm-config doesn't provide the flags to link
against the dynamic library copy of LLVM (as opposed to static), so the
script has to guess the library name. However, in some installations
(such as mine), there is no dynamic copy, which caused Dolphin to fail
to link. Change the script to do a link test. If it fails, one option
would be to fall back on static linking, but I just have it fail to
detect LLVM, because statically linking Dolphin against LLVM is really
not a great idea - huge binary, long link time.
