/*

 * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved.

 *

 * 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP

#define SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP

#include "memory/allocation.hpp"

#include "gc/shenandoah/shenandoahHeap.hpp"

#include "gc/shenandoah/shenandoahHeapRegion.hpp"

class ShenandoahHeapRegionSet;

class ShenandoahHeapRegionSetIterator : public StackObj {

private:

  const ShenandoahHeapRegionSet* _set;

  ShenandoahHeap* const _heap;

  DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile jint));

  volatile jint _current_index;

  DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);

  // No implicit copying: iterators should be passed by reference to capture the state

  ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSetIterator& that);

  ShenandoahHeapRegionSetIterator& operator=(const ShenandoahHeapRegionSetIterator& o);

public:

  ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSet* const set);

  // Reset existing iterator to new set

  void reset(const ShenandoahHeapRegionSet* const set);

  // MT version

  ShenandoahHeapRegion* claim_next();

  // Single-thread version

  ShenandoahHeapRegion* next();

};

class ShenandoahHeapRegionSet : public CHeapObj<mtGC> {

  friend class ShenandoahHeap;

private:

  ShenandoahHeap* const _heap;

  size_t const          _map_size;

  size_t const          _region_size_bytes_shift;

  jbyte* const          _set_map;

  // Bias set map's base address for fast test if an oop is in set

  jbyte* const          _biased_set_map;

  size_t                _region_count;

public:

  ShenandoahHeapRegionSet();

  ~ShenandoahHeapRegionSet();

  // Add region to set

  void add_region(ShenandoahHeapRegion* r);

  bool add_region_check_for_duplicates(ShenandoahHeapRegion* r);

  // Remove region from set

  void remove_region(ShenandoahHeapRegion* r);

  size_t count()  const { return _region_count; }

  bool is_empty() const { return _region_count == 0; }

  inline bool is_in(ShenandoahHeapRegion* r) const;

  inline bool is_in(size_t region_number)    const;

  inline bool is_in(HeapWord* p)             const;

  void print_on(outputStream* out) const;

  void clear();

private:

  jbyte* biased_map_address() const {

    return _biased_set_map;

  }

};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP