When we execute a JIT block, we have to make sure that both the PC and
the DR/IR bits of MSR are the same as they were when the block was
compiled. When jumping to a block from the dispatcher, this is done in
the way you would expect: By checking the PC and the relevant MSR bits.
However, when returning to a block using the BLR optimization, we only
check the PC. Checking the MSR bits is done by instead resetting the
stack when the MSR changes, making PC checks afterwards fail.
Except... We were only resetting the stack on rfi instructions. There
are actually many more ways for the MSR to change, and we weren't
covering those at all. I looked into resetting the stack on all of them,
but it would be pretty cumbersome both in terms of writing the code and
in terms of how often at runtime we'd have to reset the stack, so I
think the better option would be to check the MSR bits along with the
PC. That's what this commit implements.
We had one implementation of this type of data structure in Arm64Emitter
and one in VideoCommon. This moves the Arm64Emitter implementation to
its own file and adds begin and end functions to it, so that VideoCommon
can use it.
You may notice that the license header for the new file is CC0. I wrote
the Arm64Emitter implementation of SmallVector, so this should be no
problem.
Turns out that we have two subsystems that want to register CPU thread
callbacks from a different thread than the CPU thread: FreeLookConfig
and VideoConfig. Both seem to happen from the host thread before the CPU
thread starts, so there's no thread safety issue. But ideally, if we
want to allow registering callbacks from threads other than the CPU
thread, we should make registering callbacks actually thread-safe. This
is an unsolved problem for the regular Config system, so I would like to
leave it outside the scope of this PR.
This fixes a problem that started happening in CoreTimingTest after the
previous commit. CPUThreadConfigCallback registers a Config callback
only once per run of the process, but CoreTimingTest calls
Config::Shutdown after each test, and Config::Shutdown was clearing all
callbacks, preventing the callback from running after that.
In theory, our config system supports calling Set from any thread. But
because we have config callbacks that call RunAsCPUThread, it's a lot
more restricted in practice. Calling Set from any thread other than the
host thread or the CPU thread is formally thread unsafe, and calling Set
on the host thread while the CPU thread is showing a panic alert causes
a deadlock. This is especially a problem because 04072f0 made the
"Ignore for this session" button in panic alerts call Set.
Because so many of our config callbacks want their code to run on the
CPU thread, I thought it would make sense to have a centralized way to
move execution to the CPU thread for config callbacks. To solve the
deadlock problem, this new way is non-blocking. This means that threads
other than the CPU thread might continue executing before the CPU thread
is informed of the new config, but I don't think there's any problem
with that.
Intends to fix https://bugs.dolphin-emu.org/issues/13108.
In std::string, you can store strings using any encoding, but in Dolphin
we have decided to use UTF-8. The problem is that if you convert between
std::string and std::filesystem::path using the built-in methods, the
standard library will make up its own assumption of what encoding you're
using in the std::string. On most OSes this is UTF-8, but on Windows
it's whatever the user's code page is.
What I believe is the C++ standard authors' intended solution to this is
to use std::u8string instead of std::string, but that's a big hassle to
move over to, because there's no convenient way to convert between
std::string and std::u8string. Instead, in Dolphin, we have added helper
functions that convert between std::string and std::filesystem::path in
the manner we want. You *always* have to use these when converting
between std::string and std::filesystem::path, otherwise we get these
kinds of encoding problems that we've been having with custom textures.
Fixes https://bugs.dolphin-emu.org/issues/13328.
Now block link nearcode is back to a length of three instructions.
Unfortunately, the code I'm adding to Jit.cpp ends up being a bit messy
because we need to handle the case of already being in farcode...
Jumping between linked blocks currently works as follows: First, at the
end of the first block, we check if the downcount is greater than zero.
If it is, we jump to the `normalEntry` of the block. So far so good. But
if the downcount wasn't greater than zero, we jump to the `checkedEntry`
of the block, which checks the downcount *again* and then jumps to
`do_timing` if it's less than zero (which seems like an off by one error
- Jit64 doesn't do anything like this). This second check is rather
redundant. Let's jump to `do_timing` where we previously jumped to
`checkedEntry`.
Jit64 doesn't check the downcount on block entry. See 5236dc3.
Dolphin no longer supports Windows 7, so the fact that there are (were?)
more people who use Windows 7 than who use a GPU that doesn't support
the required feature is no longer relevant.
We want to have a low number of instructions between the LDP and the
MADD so that the MADD can start immediately after the LDP finishes
even if we're on a lower-end in-order CPU.
We can utilize the fact that if swapping two instructions causes another
swap to become possible, that swap involves one of the two instructions
we just swapped. There's need to search for new swap opportunities as
far back as the beginning of the block; we can just go one step back.
I've received a report from an Android user with a gamepad (a "BSP-D3")
where one physical trigger is controlling two analog axes at the same
time. This was causing RemoveSpuriousTriggerCombinations to delete both
axes, which is clearly not a desireable outcome.
With this change, now the axis with the greatest smoothness is kept,
or both in case they have the same smoothness.
Accessing any of the submenus "Buttons", "Motion Simulation" or
"Motion Input" for Wii Remotes 2-4 would actually lead to the
corresponding submenu for Wii Remote 1.
This reverts commit cfe3683668.
On Windows systems with 125% DPI scaling, this was causing both icons
and the OSD to be upscaled by 25% using nearest neighbor scaling, which
looks really bad. shuffle2 has said that this will be improved later,
but we should revert it for now for the sake of the upcoming beta build.
JosJuice