guest instruction
Single instruction blocks need to be treated specially when inline SMC
is detected, the frontend only needs to reprotect RWX and invalidate
caches then continue execution as side effects from the SMC shouldn't be
seen until the instruction executes.
Frontends need to detect this in order to handle SMC within the current
block (inline SMC) differently to regular SMC which can just reprotect
and continue.
When set - either via POPF or a thread context operation - the trap flag
raises a single step exception after the execution of each instruction.
As e.g. a JUMP instruction with TF set will raise an exception at the
jump target. Handle this on the FEX side by storing both the flag itself
(in bit 0) and a 'block exceptions' flag (in bit 1, inverted). Each
generated block when TF is set is then forced to a single instruction
with logic to raise the exception at the start. Initially after setting
TF exceptions are blocked, then at the start of the block they are
unblocked so that after the instruction executes an exception is raised
at the start of the next block.
Now that all the threading behaviour has been correctly separated/moved
to the frontend, these functions serve no purpose.
- Instead of using RunUntilExit, all threads can use `ExecuteThread`
directly, since there's nothing special about the primary thread now.
- This also removes the public function definition of `ExecutionThread` since that was only used for threading logic.
- Instead of using an exit handler, just do the same cleanup after
`ExecuteThread` has returned.
- Just make gdbserver is cleaned up early if it exists since it may
want to send some things to the connected gdb instance before
threads are exited.
These are all frontend constructs with mostly deprecated constraints.
WaitingToStart isn't used anymore, Running is effectively always true
(and behaviour has changed that if a thread is alive, it's running).
The only one that remains is `ThreadSleeping` which is only handled in
the frontend, and there was some conflation between ThreadSleeping and
Running which was hard to gauge. So delete `Running` and
`WaitingToStart`, but move `ThreadSleeping` to the frontend.
We were using this variable for two things, letting the frontend signal
to the backend that it wants to start executing once the thread is
created, and also for handling thread pausing. These two features are
conflated with one another and actually makes things more confusing.
- Move StartRunning/StartPaused to the frontend, because its a construct
that only needs to exist in the frontend
- Adds a FEX::HLE::ThreadStateObject CV for handling pausing, which only
needs to exist for gdbserver
FEXCore hasn't been returning anything other than EXIT_SHUTDOWN for a
long time, so this ended up just moving data around for no reason.
This isn't going to be used for further GdbServer work anyway, so just
completely remove it.
This is a Linux construct, move it to the frontend.
This is going to need some changes in the future since exit_group and
exit syscalls are supposed to behave differently than how FEX implements
it. For now just move it to the frontend.
Alloc::OSAllocator uses a TLS variable of the thread object so it can
use a forkable mutex plus a deferring signal section. This was setup
when the FEXCore "ExecutionThread" function is called, which is a bit
awkward and is an artifact from when the thread creation was mixed
between the frontend and the backend.
Instead let the frontend inform the backend when to install the TLS
variable.
This is one step required to make GdbServer work correctly again since
the thread initialization and pausing is awkward today.
This was working around an edge case in the GdbServer where a thread was
getting created while the process was shutting down. This edge case is
getting removed so get rid of it.
We were creating a copy of the FEXCore::Core::CPUState object when we
didn't need to. We can pass the host thread's CPUState frame through to
the creation handlers since it's read-only (so modify it to be const).
We then just move the RAX and RSP setting to /after/ the CreateThread
handling instead of before.
This reduces stack usage from ~1392 bytes to ~80 bytes.
Since the frontend has changed to informing the backend if AVX is
supported, there is no reason to feed that configuration back in to
SignalDelegator from the backend.
Instead inform the SignalDelegator directly in the frontend instead of
this now weird round-about path.
No functional change here.
- CoreRunningMode enum and variable wasn't used anymore.
- Code was moved to the frontend
- CustomCPUFactory wasn't used anymore
- All special signal handling and various features were moved to
TestHarnessRunner
- We also don't want to support actual custom CPU cores.
- TestHarnessRunner just runs as a host runner if compiled on an
x86-64 device if vixl sim isn't enabled now.
- Removes the Core config option entirely.
- Moves VDSOPointers struct to the frontend
- Every use of this lives in the Linux frontend instead now
These are a Linux construct and should live here. Removes a weird
passthrough API from FEXCore and keeps it in the frontend instead.
This isn't even typically allocated in a real setup, as it's only a
fallback for if VDSO isn't loaded.
The CallbackReturn function stays in FEXCore because it would have
caused an API in the other direction instead.
The MIDR querying is inherently OS specific and needs a bit of special
casing. Instead let the frontend inform FEXCore how many CPU cores there
are and their MIDRs instead.
This lets us keep the Linux specific code in the frontend.
This used to exist in the FEXCore header since the unaligned handler was
done in the frontend. Once it got moved in to FEXCore it had stayed
there. Move it over now.
Billy Laws