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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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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,
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#ifndef SHARE_GC_Z_ZLIVEMAP_HPP
#define SHARE_GC_Z_ZLIVEMAP_HPP

#include "gc/z/zAddress.hpp"
#include "gc/z/zBitMap.hpp"
#include "gc/z/zGenerationId.hpp"
#include "memory/allocation.hpp"

class ObjectClosure;

class ZLiveMap {
  friend class ZLiveMapTest;

private:
  static const uint32_t NumSegments = 64;
  static const uint32_t BitsPerObject = 2;

  const uint32_t    _segment_size;
  const int         _segment_shift;

  volatile uint32_t _seqnum;
  volatile uint32_t _live_objects;
  volatile size_t   _live_bytes;
  BitMap::bm_word_t _segment_live_bits;
  BitMap::bm_word_t _segment_claim_bits;
  ZBitMap           _bitmap;

  const BitMapView segment_live_bits() const;
  const BitMapView segment_claim_bits() const;

  BitMapView segment_live_bits();
  BitMapView segment_claim_bits();

  BitMap::idx_t segment_start(BitMap::idx_t segment) const;
  BitMap::idx_t segment_end(BitMap::idx_t segment) const;

  bool is_segment_live(BitMap::idx_t segment) const;
  bool set_segment_live(BitMap::idx_t segment);

  BitMap::idx_t first_live_segment() const;
  BitMap::idx_t next_live_segment(BitMap::idx_t segment) const;
  BitMap::idx_t index_to_segment(BitMap::idx_t index) const;

  bool claim_segment(BitMap::idx_t segment);

  void initialize_bitmap();

  void reset(ZGenerationId id);
  void reset_segment(BitMap::idx_t segment);

  size_t do_object(ObjectClosure* cl, zaddress addr) const;

  template <typename Function>
  void iterate_segment(BitMap::idx_t segment, Function function);

public:
  ZLiveMap(uint32_t object_max_count);
  ZLiveMap(const ZLiveMap& other) = delete;

  void reset();

  bool is_marked(ZGenerationId id) const;

  uint32_t live_objects() const;
  size_t live_bytes() const;

  bool get(ZGenerationId id, BitMap::idx_t index) const;
  bool set(ZGenerationId id, BitMap::idx_t index, bool finalizable, bool& inc_live);

  void inc_live(uint32_t objects, size_t bytes);

  template <typename Function>
  void iterate(ZGenerationId id, Function function);

  BitMap::idx_t find_base_bit(BitMap::idx_t index);
  BitMap::idx_t find_base_bit_in_segment(BitMap::idx_t start, BitMap::idx_t index);
};

#endif // SHARE_GC_Z_ZLIVEMAP_HPP