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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * 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).
 *
 * 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_G1_G1EDENREGIONS_HPP
#define SHARE_GC_G1_G1EDENREGIONS_HPP

#include "gc/g1/heapRegion.hpp"
#include "runtime/globals.hpp"
#include "utilities/debug.hpp"

class G1EdenRegions {
private:
  int    _length;
  // Sum of used bytes from all retired eden regions.
  // I.e. updated when mutator regions are retired.
  volatile size_t _used_bytes;

public:
  G1EdenRegions() : _length(0), _used_bytes(0) { }

  // Called when a heap region is added to eden region.
  void add(HeapRegion* hr) {
    assert(!hr->is_eden(), "should not already be set");
    _length++;
  }

  void clear() {
    _length = 0;
    _used_bytes = 0;
  }

  // Returns actual number of heap regions tagged as eden.
  // I.e. retained heap region is also included.
  uint length() const { return _length; }

  // Sum of used bytes of all eden regions except used bytes of a retained region.
  size_t used_bytes() const { return _used_bytes; }

  // Called when the mutator region retires.
  // Exclude used bytes of a retained region.
  void add_used_bytes(HeapRegion* alloc_region, size_t used_bytes) {
    _used_bytes += used_bytes;
  }
};

#endif // SHARE_GC_G1_G1EDENREGIONS_HPP