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:
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 $PATH. The theory is that higan forks,
then the child tries to exec icarus and fails, so it exits, all the
unique_ptrs clean up their resources and tell the X server to free
things the parent process is still using. Calling _exit() prevents
destructors from running, and seems to prevent the problem. -Ed.]
byuu says:
Changelog:
- WS: fixed sprite window clipping (again)
- WS: don't set IRQ status bits of IRQ enable bits are clear
- SFC: signed/unsigned -> int/uint for DSP core
- SFC: removed eBoot
- SFC: added 21fx (not the same as the old precursor to MSU1; just
reusing the name)
Note: XI Little doesn't seem to be fixed after all ... but the other
three are. So I guess we're at 13 bugs :( And holy shit that music when
you choose a menu option is one of the worst sounds I've ever heard in
my life >_<
byuu says:
Changelog:
- icarus: WS/C detects RAM type/size heuristically now
- icarus: WS/C uses ram type=$type instead of $type
- WS: use back color instead of white for backdrop
- WS: fixed sprite count limit; removes all the garbled sprites from
GunPey
- WS: hopefully fixed sprite priority with screen 2
- WS: implemented keypad polling; GunPey is now fully playable
- SNES: added Super Disc expansion port device (doesn't do anything,
just for testing)
Note: WS is hard-coded to vertical orientation right now. But there's
basic code in there for all the horizontal stuff.
byuu says:
Changelog:
- restructured the project and removed a whole bunch of old/dead
directives from higan/GNUmakefile
- huge amounts of work on hiro/cocoa (compiles but ~70% of the
functionality is commented out)
- fixed a masking error in my ARM CPU disassembler [Lioncash]
- SFC: decided to change board cic=(411,413) back to board
region=(ntsc,pal) ... the former was too obtuse
If you rename Boolean (it's a problem with an include from ruby, not
from hiro) and disable all the ruby drivers, you can compile an
OS X binary, but obviously it's not going to do anything.
It's a boring WIP, I just wanted to push out the project structure
change now at the start of this WIP cycle.
Tim Allen