changed the `process_frames` argument in the construction of the `RegisterMap` in `OptoRuntime::handle_exception_C()` from `true` to `false`. That should be ok, since we don't touch any oops in that context. However, that changed caused intermittent failures in testing.
later reverted that change and worked around it by instead adding a ThreadWXEnable scope in `ZBarrierSetNMethod::nmethod_entry_barrier()`. However, it seems like the original fix in
might have uncovered some other issue that we should investigate further as it suggests that we might not be processing a frame somewhere else where we should.