// Whenever a thread transitions from native to vm/java it must suspend
  // if external|deopt suspend is present.

  bool is_suspend_after_native() const {

  {- -------------------------------------------
  (1) _suspend_flags 中の _external_suspend ビット, もしくは _deopt_suspend ビットが立っていれば, true をリターンする.
      (See: [here](no2114zBI.html) for details)
      ---------------------------------------- -}

        return (_suspend_flags & (_external_suspend | _deopt_suspend) ) != 0;
      }