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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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#ifndef SHARE_GC_SHENANDOAH_SHENANDOAHMARK_HPP
#define SHARE_GC_SHENANDOAH_SHENANDOAHMARK_HPP

#include "gc/shared/ageTable.hpp"
#include "gc/shared/stringdedup/stringDedup.hpp"
#include "gc/shared/taskTerminator.hpp"
#include "gc/shenandoah/shenandoahGeneration.hpp"
#include "gc/shenandoah/shenandoahGenerationType.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahTaskqueue.hpp"

enum StringDedupMode {
  NO_DEDUP,      // Do not do anything for String deduplication
  ENQUEUE_DEDUP, // Enqueue candidate Strings for deduplication, if meet age threshold
  ALWAYS_DEDUP   // Enqueue Strings for deduplication
};

class ShenandoahMarkingContext;
class ShenandoahReferenceProcessor;

// Base class for mark
// Mark class does not maintain states. Instead, mark states are
// maintained by task queues, mark bitmap and SATB buffers (concurrent mark)
class ShenandoahMark: public StackObj {
protected:
  ShenandoahGeneration* const _generation;
  ShenandoahObjToScanQueueSet* const _task_queues;
  ShenandoahObjToScanQueueSet* const _old_gen_task_queues;

protected:
  ShenandoahMark(ShenandoahGeneration* generation);

public:
  template<class T, ShenandoahGenerationType GENERATION>
  static inline void mark_through_ref(T* p, ShenandoahObjToScanQueue* q, ShenandoahObjToScanQueue* old_q, ShenandoahMarkingContext* const mark_context, bool weak);

  // Loom support
  void start_mark();
  void end_mark();

  // Helpers
  inline ShenandoahObjToScanQueueSet* task_queues() const;
  ShenandoahObjToScanQueueSet* old_task_queues() {
    return _old_gen_task_queues;
  }

  inline ShenandoahObjToScanQueue* get_queue(uint index) const;
  inline ShenandoahObjToScanQueue* get_old_queue(uint index) const;

  inline ShenandoahGeneration* generation() { return _generation; };

private:
// ---------- Marking loop and tasks

  template <class T, ShenandoahGenerationType GENERATION, StringDedupMode STRING_DEDUP>
  inline void do_task(ShenandoahObjToScanQueue* q, T* cl, ShenandoahLiveData* live_data, StringDedup::Requests* const req, ShenandoahMarkTask* task, uint worker_id);

  template <class T>
  inline void do_chunked_array_start(ShenandoahObjToScanQueue* q, T* cl, oop array, bool weak);

  template <class T>
  inline void do_chunked_array(ShenandoahObjToScanQueue* q, T* cl, oop array, int chunk, int pow, bool weak);

  template <ShenandoahGenerationType GENERATION>
  inline void count_liveness(ShenandoahLiveData* live_data, oop obj, uint worker_id);

  template <class T, ShenandoahGenerationType GENERATION, bool CANCELLABLE, StringDedupMode STRING_DEDUP>
  void mark_loop_work(T* cl, ShenandoahLiveData* live_data, uint worker_id, TaskTerminator *t, StringDedup::Requests* const req);

  template <ShenandoahGenerationType GENERATION, bool CANCELLABLE, StringDedupMode STRING_DEDUP>
  void mark_loop_prework(uint worker_id, TaskTerminator *terminator, ShenandoahReferenceProcessor *rp, StringDedup::Requests* const req, bool update_refs);

  template <ShenandoahGenerationType GENERATION>
  static bool in_generation(ShenandoahHeap* const heap, oop obj);

  template <class T>
  static void mark_non_generational_ref(T *p, ShenandoahObjToScanQueue* q, ShenandoahMarkingContext* const mark_context, bool weak);

  static void mark_ref(ShenandoahObjToScanQueue* q,
                       ShenandoahMarkingContext* const mark_context,
                       bool weak, oop obj);

  template <StringDedupMode STRING_DEDUP>
  inline void dedup_string(oop obj, StringDedup::Requests* const req);
protected:
  template<bool CANCELLABLE, StringDedupMode STRING_DEDUP>
  void mark_loop(uint worker_id, TaskTerminator* terminator, ShenandoahReferenceProcessor *rp,
                 ShenandoahGenerationType generation, StringDedup::Requests* const req);

  void mark_loop(uint worker_id, TaskTerminator* terminator, ShenandoahReferenceProcessor *rp,
                 ShenandoahGenerationType generation, bool cancellable, StringDedupMode dedup_mode, StringDedup::Requests* const req);
};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHMARK_HPP