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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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#include "gc/g1/g1YCTypes.hpp"

#include "utilities/globalDefinitions.hpp"

// State of the G1 collection.

class G1CollectorState {

  // Indicates whether we are in the phase where we do partial gcs that only contain

  // the young generation. Not set while _in_full_gc is set.

  bool _in_young_only_phase;

  // Indicates whether we are in the last young gc before the mixed gc phase. This GC

  // is required to keep pause time requirements.

  bool _in_young_gc_before_mixed;

  // If _initiate_conc_mark_if_possible is set at the beginning of a

  // pause, it is a suggestion that the pause should start a marking

  // cycle by doing the initial-mark work. However, it is possible

  // that the concurrent marking thread is still finishing up the

  // previous marking cycle (e.g., clearing the next marking

  // bitmap). If that is the case we cannot start a new cycle and

  // we'll have to wait for the concurrent marking thread to finish

  // what it is doing. In this case we will postpone the marking cycle

  // initiation decision for the next pause. When we eventually decide

  // to start a cycle, we will set _in_initial_mark_gc which

  // will stay true until the end of the initial-mark pause doing the

  // initial-mark work.

  volatile bool _in_initial_mark_gc;

  // At the end of a pause we check the heap occupancy and we decide

  // whether we will start a marking cycle during the next pause. If

  // we decide that we want to do that, set this parameter. This parameter will

  // stay set until the beginning of a subsequent pause (not necessarily

  // the next one) when we decide that we will indeed start a marking cycle and

  // do the initial-mark work.

  volatile bool _initiate_conc_mark_if_possible;

  // Marking or rebuilding remembered set work is in progress. Set from the end

  // of the initial mark pause to the end of the Cleanup pause.

  bool _mark_or_rebuild_in_progress;

  // The next bitmap is currently being cleared or about to be cleared. TAMS and bitmap

  // may be out of sync.

  bool _clearing_next_bitmap;

  // Set during a full gc pause.

  bool _in_full_gc;

public:

  G1CollectorState() :

    _in_young_only_phase(true),

    _in_young_gc_before_mixed(false),

    _in_initial_mark_gc(false),

    _initiate_conc_mark_if_possible(false),

    _mark_or_rebuild_in_progress(false),

    _clearing_next_bitmap(false),

    _in_full_gc(false) { }

  // Phase setters

  void set_in_young_only_phase(bool v) { _in_young_only_phase = v; }

  // Pause setters

  void set_in_young_gc_before_mixed(bool v) { _in_young_gc_before_mixed = v; }

  void set_in_initial_mark_gc(bool v) { _in_initial_mark_gc = v; }

  void set_in_full_gc(bool v) { _in_full_gc = v; }

  void set_initiate_conc_mark_if_possible(bool v) { _initiate_conc_mark_if_possible = v; }

  void set_mark_or_rebuild_in_progress(bool v) { _mark_or_rebuild_in_progress = v; }

  void set_clearing_next_bitmap(bool v) { _clearing_next_bitmap = v; }

  // Phase getters

  bool in_young_only_phase() const { return _in_young_only_phase && !_in_full_gc; }

  bool in_mixed_phase() const { return !in_young_only_phase() && !_in_full_gc; }

  // Specific pauses

  bool in_young_gc_before_mixed() const { return _in_young_gc_before_mixed; }

  bool in_full_gc() const { return _in_full_gc; }

  bool in_initial_mark_gc() const { return _in_initial_mark_gc; }

  bool initiate_conc_mark_if_possible() const { return _initiate_conc_mark_if_possible; }

  bool mark_or_rebuild_in_progress() const { return _mark_or_rebuild_in_progress; }

  bool clearing_next_bitmap() const { return _clearing_next_bitmap; }

  G1YCType yc_type() const {

    if (in_initial_mark_gc()) {

      return InitialMark;

    } else if (mark_or_rebuild_in_progress()) {

      return DuringMarkOrRebuild;

    } else if (in_young_only_phase()) {

      return Normal;

    } else {

      return Mixed;

    }

  }

};