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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * 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).
 *
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 * 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_Z_ZHEAPITERATOR_HPP
#define SHARE_GC_Z_ZHEAPITERATOR_HPP

#include "gc/shared/collectedHeap.hpp"
#include "gc/shared/taskqueue.hpp"
#include "gc/shared/taskTerminator.hpp"
#include "gc/z/zGranuleMap.hpp"
#include "gc/z/zLock.hpp"
#include "gc/z/zRootsIterator.hpp"
#include "gc/z/zStat.hpp"

class ZHeapIteratorBitMap;
class ZHeapIteratorContext;

using ZHeapIteratorBitMaps = ZGranuleMap<ZHeapIteratorBitMap*>;
using ZHeapIteratorBitMapsIterator = ZGranuleMapIterator<ZHeapIteratorBitMap*, false /* Parallel */>;
using ZHeapIteratorQueue = OverflowTaskQueue<oop, mtGC>;
using ZHeapIteratorQueues = GenericTaskQueueSet<ZHeapIteratorQueue, mtGC>;
using ZHeapIteratorArrayChunkQueue = OverflowTaskQueue<ObjArrayTask, mtGC>;
using ZHeapIteratorArrayChunkQueues = GenericTaskQueueSet<ZHeapIteratorArrayChunkQueue, mtGC>;

class ZHeapIterator : public ParallelObjectIteratorImpl {
  friend class ZHeapIteratorCLDOopClosure;
  template <bool Weak> friend class ZHeapIteratorColoredRootOopClosure;
  template <bool VisitReferents> friend class ZHeapIteratorOopClosure;
  friend class ZHeapIteratorUncoloredRootOopClosure;

private:
  const bool                    _visit_weaks;
  const bool                    _for_verify;
  ZHeapIteratorBitMaps          _bitmaps;
  ZLock                         _bitmaps_lock;
  ZHeapIteratorQueues           _queues;
  ZHeapIteratorArrayChunkQueues _array_chunk_queues;
  ZRootsIteratorStrongColored   _roots_colored;
  ZRootsIteratorStrongUncolored _roots_uncolored;
  ZRootsIteratorWeakColored     _roots_weak_colored;
  TaskTerminator                _terminator;

  ZHeapIteratorBitMap* object_bitmap(oop obj);

  bool should_visit_object_at_mark() const;
  bool should_visit_object_at_follow() const;

  bool mark_object(oop obj);

  void push_strong_roots(const ZHeapIteratorContext& context);
  void push_weak_roots(const ZHeapIteratorContext& context);

  template <bool VisitWeaks>
  void push_roots(const ZHeapIteratorContext& context);

  void mark_visit_and_push(const ZHeapIteratorContext& context, oop obj);

  template <bool VisitReferents>
  void follow_object(const ZHeapIteratorContext& context, oop obj);

  void follow_array(const ZHeapIteratorContext& context, oop obj);
  void follow_array_chunk(const ZHeapIteratorContext& context, const ObjArrayTask& array);

  template <bool VisitWeaks>
  void follow(const ZHeapIteratorContext& context, oop obj);

  template <bool VisitWeaks>
  void visit_and_follow(const ZHeapIteratorContext& context, oop obj);

  template <bool VisitWeaks>
  void drain(const ZHeapIteratorContext& context);

  template <bool VisitWeaks>
  void steal(const ZHeapIteratorContext& context);

  bool steal(const ZHeapIteratorContext& context, oop& obj);
  bool steal_array_chunk(const ZHeapIteratorContext& context, ObjArrayTask& array);

  template <bool VisitWeaks>
  void drain_and_steal(const ZHeapIteratorContext& context);

  template <bool VisitWeaks>
  void object_iterate_inner(const ZHeapIteratorContext& context);

public:
  ZHeapIterator(uint nworkers, bool visit_weaks, bool for_verify);
  virtual ~ZHeapIterator();

  virtual void object_iterate(ObjectClosure* object_cl, uint worker_id);
  void object_and_field_iterate(ObjectClosure* object_cl, OopFieldClosure* field_cl, uint worker_id);
};

#endif // SHARE_GC_Z_ZHEAPITERATOR_HPP