[libunwind] [SEH] Add debug logging in __libunwind_seh_personality

libunwind/src/Unwind-seh.cpp

__libunwind_seh_personality(int version, _Unwind_Action state,
   ms_exc.ExceptionCode = STATUS_GCC_THROW;
   ms_exc.ExceptionFlags = 0;
   ms_exc.NumberParameters = 3;
   ms_exc.ExceptionInformation[0] = (ULONG_PTR)exc;
   ms_exc.ExceptionInformation[1] = (ULONG_PTR)context;
   ms_exc.ExceptionInformation[2] = state;
   DISPATCHER_CONTEXT *disp_ctx =
       __unw_seh_get_disp_ctx((unw_cursor_t *)context);
+  _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() calling "
+                             "LanguageHandler %p(%p, %p, %p, %p)",
+                             (void *)disp_ctx->LanguageHandler, (void *)&ms_exc,
+                             (void *)disp_ctx->EstablisherFrame,
+                             (void *)disp_ctx->ContextRecord, (void *)disp_ctx);
   EXCEPTION_DISPOSITION ms_act = disp_ctx->LanguageHandler(&ms_exc,
                                                            (PVOID)disp_ctx->EstablisherFrame,
                                                            disp_ctx->ContextRecord,
                                                            disp_ctx);
+  _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() LanguageHandler "
+                             "returned %d",
+                             (int)ms_act);
   switch (ms_act) {
   case ExceptionContinueExecution: return _URC_END_OF_STACK;
   case ExceptionContinueSearch: return _URC_CONTINUE_UNWIND;
   case 4 /*ExceptionExecuteHandler*/:
     return phase2 ? _URC_INSTALL_CONTEXT : _URC_HANDLER_FOUND;
   default:
     return phase2 ? _URC_FATAL_PHASE2_ERROR : _URC_FATAL_PHASE1_ERROR;
   }