_Unwind_GetCFA
uint64_t fp = _Unwind_GetCFA(ctx);
uint64_t _Unwind_GetCFA(struct _Unwind_Context *context);
cfa = _Unwind_GetCFA(context);
fp = _Unwind_GetCFA(ctx);
exception_object->private_2 = _Unwind_GetCFA(ctx);
if (exception_object->private_2 == _Unwind_GetCFA(ctx)) {