inline void ParallelCompactData::RegionData::set_completed()
{

  {- -------------------------------------------
  (1) _dc_and_los フィールド(の上の方)に dc_completed 値を書き込む.
      ---------------------------------------- -}

      assert(claimed(), "must be claimed first");
      _dc_and_los = dc_completed | (region_sz_t) live_obj_size();
    }