byuu says:
(Windows: compile with -fpermissive to silence an annoying error. I'll
fix it in the next WIP.)
I completely replaced the time management system in higan and overhauled
the scheduler.
Before, processor threads would have "int64 clock"; and there would
be a 1:1 relationship between two threads. When thread A ran for X
cycles, it'd subtract X * B.Frequency from clock; and when thread B ran
for Y cycles, it'd add Y * A.Frequency from clock. This worked well
and allowed perfect precision; but it doesn't work when you have more
complicated relationships: eg the 68K can sync to the Z80 and PSG; the
Z80 to the 68K and PSG; so the PSG needs two counters.
The new system instead uses a "uint64 clock" variable that represents
time in attoseconds. Every time the scheduler exits, it subtracts
the smallest clock count from all threads, to prevent an overflow
scenario. The only real downside is that rounding errors mean that
roughly every 20 minutes, we have a rounding error of one clock cycle
(one 20,000,000th of a second.) However, this only applies to systems
with multiple oscillators, like the SNES. And when you're in that
situation ... there's no such thing as a perfect oscillator anyway. A
real SNES will be thousands of times less out of spec than 1hz per 20
minutes.
The advantages are pretty immense. First, we obviously can now support
more complex relationships between threads. Second, we can build a
much more abstracted scheduler. All of libco is now abstracted away
completely, which may permit a state-machine / coroutine version of
Thread in the future. We've basically gone from this:
auto SMP::step(uint clocks) -> void {
clock += clocks * (uint64)cpu.frequency;
dsp.clock -= clocks;
if(dsp.clock < 0 && !scheduler.synchronizing()) co_switch(dsp.thread);
if(clock >= 0 && !scheduler.synchronizing()) co_switch(cpu.thread);
}
To this:
auto SMP::step(uint clocks) -> void {
Thread::step(clocks);
synchronize(dsp);
synchronize(cpu);
}
As you can see, we don't have to do multiple clock adjustments anymore.
This is a huge win for the SNES CPU that had to update the SMP, DSP, all
peripherals and all coprocessors. Likewise, we don't have to synchronize
all coprocessors when one runs, now we can just synchronize the active
one to the CPU.
Third, when changing the frequencies of threads (think SGB speed setting
modes, GBC double-speed mode, etc), it no longer causes the "int64
clock" value to be erroneous.
Fourth, this results in a fairly decent speedup, mostly across the
board. Aside from the GBA being mostly a wash (for unknown reasons),
it's about an 8% - 12% speedup in every other emulation core.
Now, all of this said ... this was an unbelievably massive change, so
... you know what that means >_> If anyone can help test all types of
SNES coprocessors, and some other system games, it'd be appreciated.
----
Lastly, we have a bitchin' new about screen. It unfortunately adds
~200KiB onto the binary size, because the PNG->C++ header file
transformation doesn't compress very well, and I want to keep the
original resource files in with the higan archive. I might try some
things to work around this file size increase in the future, but for now
... yeah, slightly larger archive sizes, sorry.
The logo's a bit busted on Windows (the Label control's background
transparency and alignment settings aren't working), but works well on
GTK. I'll have to fix Windows before the next official release. For now,
look on my Twitter feed if you want to see what it's supposed to look
like.
----
EDIT: forgot about ICD2::Enter. It's doing some weird inverse
run-to-save thing that I need to implement support for somehow. So, save
states on the SGB core probably won't work with this WIP.
byuu says:
Changelog:
- nall::lstring -> nall::string_vector
- added IntegerBitField<type, lo, hi> -- hopefully it works correctly...
- Multitap 1-4 -> Super Multitap 2-5
- fixed SFC PPU CGRAM read regression
- huge amounts of SFC PPU IO register cleanups -- .bits really is lovely
- re-added the read/write(VRAM,OAM,CGRAM) helpers for the SFC PPU
- but they're now optimized to the realities of the PPU (16-bit data
sizes / no address parameter / where appropriate)
- basically used to get the active-display overrides in a unified place;
but also reduces duplicate code in (read,write)IO
byuu says:
It took several hours, but I've rebuilt much of the SNES' bus memory
mapping architecture.
The new design unifies the cartridge string-based mapping
("00-3f,80-bf:8000-ffff") and internal bus.map calls. The map() function
now has an accompanying unmap() function, and instead of a fixed 256
callbacks, it'll scan to find the first available slot. unmap() will
free slots up when zero addresses reference a given slot.
The controllers and expansion port are now both entirely dynamic.
Instead of load/unload/power/reset, they only have the constructor
(power/reset/load) and destructor (unload). What this means is you can
now dynamically change even expansion port devices after the system is
loaded.
Note that this is incredibly dangerous and stupid, but ... oh well. The
whole point of this was for 21fx. There's no way to change the expansion
port device prior to loading a game, but if the 21fx isn't active, then
the reset vector hijack won't work. Now you can load a 21fx game, change
the expansion port device, and simply reset the system to active the
device.
The unification of design between controller port devices and expansion
port devices is nice, and overall this results in a reduction of code
(all of the Mapping stuff in Cartridge is gone, replaced with direct bus
mapping.) And there's always the potential to expand this system more in
the future now.
The big missing feature right now is the ability to push/pop mappings.
So if you look at how the 21fx does the reset vector, you might vomit
a little bit. But ... it works.
Also changed exit(0) to _exit(0) in the POSIX version of nall::execute.
[The _exit(0) thing is an attempt to make higan not crash when it tries
to launch icarus and it's not on $PATH. The theory is that higan forks,
then the child tries to exec icarus and fails, so it exits, all the
unique_ptrs clean up their resources and tell the X server to free
things the parent process is still using. Calling _exit() prevents
destructors from running, and seems to prevent the problem. -Ed.]
byuu says:
Changelog:
- SFC: balanced profile removed
- SFC: performance profile removed
- SFC: code for handling non-threaded CPU, SMP, DSP, PPU removed
- SFC: Coprocessor, Controller (and expansion port) shared Thread code
merged to SFC::Cothread
- Cothread here just means "Thread with CPU affinity" (couldn't think
of a better name, sorry)
- SFC: CPU now has vector<Thread*> coprocessors, peripherals;
- this is the beginning of work to allow expansion port devices to be
dynamically changed at run-time
- ruby: all audio drivers default to 48000hz instead of 22050hz now if
no frequency is assigned
- note: the WASAPI driver can default to whatever the native frequency
is; doesn't have to be 48000hz
- tomoko: removed the ability to change the frequency from the UI (but
it will display the frequency used)
- tomoko: removed the timing settings panel
- the goal is to work toward smooth video via adaptive sync
- the model is broken by not being in control of the audio frequency
anyway
- it's further broken by PAL running at 50hz and WSC running at 75hz
- it was always broken anyway by SNES interlace timing varying from
progressive timing
- higan: audio/ stub created (for now, it's just nall/dsp/ moved here
and included as a header)
- higan: video/ stub created
- higan/GNUmakefile: now includes build rules for essential components
(libco, emulator, audio, video)
The audio changes are in preparation to merge wareya's awesome WASAPI
work without the need for the nall/dsp resampler.
byuu says:
Changelog:
- WS: fixed sprite window clipping (again)
- WS: don't set IRQ status bits of IRQ enable bits are clear
- SFC: signed/unsigned -> int/uint for DSP core
- SFC: removed eBoot
- SFC: added 21fx (not the same as the old precursor to MSU1; just
reusing the name)
Note: XI Little doesn't seem to be fixed after all ... but the other
three are. So I guess we're at 13 bugs :( And holy shit that music when
you choose a menu option is one of the worst sounds I've ever heard in
my life >_<
Tim Allen