Prevents invalidations being missed under the following circumstances:
Thread A JITs block A into the global codebuffer, adding the guest to host
mapping to its CodePages, thread A is then killed.
Thread B then performs SMC on block A. An exception will be triggered but
as CodePages was stored per-thread, and thread A is now killed when all
threads are iterated over by the frontend to perform invalidations it
will be missed.
The accumulator is introduced to handle the case where multiple threads
have the same code entry in their local caches but share the same codebuffer.
Consider a thread C in the above example that also has block A in its cache,
without an accumulator, when invalidating thread B the entrypoint of A is erased
from the shared guest to host map. So when C is invalidated, the local cache entry
for A is not removed since it was removed from CodePages when invalidating B.
As section permissions are set on the unix side we don't get a
protection callback for them, workaround this by iterating over
the sections of all executables after mapping and tracking the RWX
ones.
Unmapping a section will unmap the whole size initially allocated,
irrespective of how their protections are changed afterwards. Make sure
to follow this logic for invalidation too.
When thread management was moved to the frontend, invalidation moved
from being a global operation to per-thread but the WOW64 backend wasn't
updated to account for this. Now for any invalidation event loop over
all threads tracked by the frontend and invalidate the appropriate
range.
FEXCore includes was including an FHU header which would result in
compilation failure for external projects trying to link to libFEXCore.
Moves it over to fix this, it was the only FHU usage in FEXCore/include
NFC
Billy Laws