This isn't quite a 100% clean sweep of IWYU.
There are some false positives where clang fails.
Additionally there are still a few missed in the frontend side of things
that I didn't get to
This is working towards getting the stack frame for guest signals being
pushed over to the Frontend.
Still some more work to do but this is the first step that can be split
up.
In the case of SRA plus a signal not using siginfo then we were not
spilling SRA registers.
In this case we would then shift the signal frame and fill the guest
context with garbage register data.
This would potentially cause some issues but haven't noticed anything
outside outside of my test applications.
Hangover currently abuses the syscall op for thunking purposes.
Very likely this will be changed in the future but for now make sure to
support that use case.
This was using the implicit thread TLS object. All users of this
have access to the thread object directly.
Use that instead. Fixes a subtle bug were the frontend could be trying
to do a callback and TLS sections weren't correctly set.
This always returns success and for easier state management, just return
our parent thread.
Frontend needs full visibility of this state anyway for thread
management.
si_addr is set to the address that is trying to be accessed, not the RIP
that is trying to access it.
We just need to copy our host value over for this.
SIGFPE and SIGILL we still don't have a good answer for.
We were checking the PC after we set the new location in the data
structure.
Didn't matter for x86-64 since it doesn't use SRA but it does matter for
ARM.
Now on signal while in JIT code it will spill correctly
MOVS, LODS, and STOS ops are only documented to support the REP prefix.
These instructions actually repeat correctly with the REPNE prefix as
well.
Behaviour is the same.
Fixes POD Gold
32-bit doesn't store XMM registers 8-15 since they don't exist there.
This technically falls under the "reserved" slot so applications can't
rely on them to not be written.
Saves us a bit of CPU overhead at the very least
There are two checks to the alt stack that the signal handler needs to
check.
First it needs to check if the signal handler was registered with teh
flag SA_ONSTACK.
Then it needs to check if the alt stack is actually enabled by not
having flag SS_DISABLE.
Additionally, 32-bit x86 doesn't have a redzone so stop offsetting by
128
We were failing to store the updated ESP on 32-bit.
On 64-bit or CPL change (which we don't support) the stack pointer is
pulled from the frame.
This resolves an issue in wine's 32-bit loader where it was getting zero
for one of the context pointers since the stack pointer wasn't adjusted
This information is only ever going to be offline. Will be useful for multiple reasons.
1) Searching for split lock usage in applications, which can be a programming bug.
a) This isn't visible on AMD systems and on Intel is a fairly new linux feature
2) Having more information about when an application breaks.
3) Useful for some minor profiling for devs looking for statistical data
A decent amount of this was broken.
To the point that the ABI was incorrect even, causing 32-bit signals to completely crash in most instances.
This is enough to get my 32-bit signal handler test application to work and basic SIGUSR behaviour
vsyscall is a legacy interface to expose three syscalls in a faster fashion.
Most applications should have moved to vDSO but this isn't entirely the case.
golang specifically still used vsyscall in the case that vdso isn't available.
Which that isn't completely safe since vsyscall can be completely disabled.
This is fixed in a newer version of their runtime but we must support legacy behaviour.
This makes it so FEX checks if the incoming RIP is a "special" region and adjusts where it
loads instructions from accordingly. Lying to the guest application about the instruction stream
while maintaining the illusion that its RIP is in the correct location.
This was fairly straightforward since we already decoupled the instruction stream from the RIP location.
This fixes golang execution as long as you also disable their preempt signaling.
environment variable to do so is `GODEBUG=asyncpreemptoff=1`
These are some fairly large separate files still.
Don't want these to be too terribly small but helps significantly with compile time when working
in the OpcodeDispatcher
Prior to the introduction of fmt, there wasn't a nice and easy way to
format std::string_view, but now that we have it in place, we can modify
relevant log calls to make use of it and get rid of the need to
construct a string around the view.
While we're in the same area, we can make the rest of the modified file
use fmt where appropriate.
The entire object didn't need to be an Allocator.
Additionally there was an overwrite happening on the Size variable.
This was causing the shutdown to free a size of zero.
MUL is handled in a different function, so this isn't needed there anymore.
This was causing a problem where if you force enabled LOCK on all capable ops it was causing a crash.
Issue #1164 is set to track getting unit tests for these.
This needs to end up 32-bit space which means we shouldn't use the FEXCore Allocator.
FEXCore allocator has a hack in it for fixed offset in 32-bit space, but we shouldn't rely on it
In the case that paranoid TSO is enabled, we can force all unaligned loadstores
down this path.
Instead of backpatching, just do the unaligned loadstore in the handler
Ryan Houdek