/*

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * 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_SHARED_COLLECTORPOLICY_HPP

#define SHARE_GC_SHARED_COLLECTORPOLICY_HPP

#include "gc/shared/barrierSet.hpp"

#include "gc/shared/cardTableRS.hpp"

#include "gc/shared/generationSpec.hpp"

#include "memory/allocation.hpp"

#include "utilities/macros.hpp"

// This class (or more correctly, subtypes of this class)

// are used to define global garbage collector attributes.

// This includes initialization of generations and any other

// shared resources they may need.

//

// In general, all flag adjustment and validation should be

// done in initialize_flags(), which is called prior to

// initialize_size_info().

//

// This class is not fully developed yet. As more collector(s)

// are added, it is expected that we will come across further

// behavior that requires global attention. The correct place

// to deal with those issues is this class.

// Forward declarations.

class GenCollectorPolicy;

class AdaptiveSizePolicy;

class ConcurrentMarkSweepPolicy;

class G1CollectorPolicy;

class MarkSweepPolicy;

class CollectorPolicy : public CHeapObj<mtGC> {

 protected:

  virtual void initialize_alignments() = 0;

  virtual void initialize_flags();

  virtual void initialize_size_info();

  DEBUG_ONLY(virtual void assert_flags();)

  DEBUG_ONLY(virtual void assert_size_info();)

  size_t _initial_heap_byte_size;

  size_t _max_heap_byte_size;

  size_t _min_heap_byte_size;

  size_t _space_alignment;

  size_t _heap_alignment;

  CollectorPolicy();

 public:

  void initialize_all() {

    initialize_alignments();

    initialize_flags();

    initialize_size_info();

  }

  // Return maximum heap alignment that may be imposed by the policy.

  static size_t compute_heap_alignment();

  size_t space_alignment()        { return _space_alignment; }

  size_t heap_alignment()         { return _heap_alignment; }

  size_t initial_heap_byte_size() { return _initial_heap_byte_size; }

  size_t max_heap_byte_size()     { return _max_heap_byte_size; }

  size_t min_heap_byte_size()     { return _min_heap_byte_size; }

};

class GenCollectorPolicy : public CollectorPolicy {

  friend class TestGenCollectorPolicy;

  friend class VMStructs;

protected:

  size_t _min_young_size;

  size_t _initial_young_size;

  size_t _max_young_size;

  size_t _min_old_size;

  size_t _initial_old_size;

  size_t _max_old_size;

  // _gen_alignment and _space_alignment will have the same value most of the

  // time. When using large pages they can differ.

  size_t _gen_alignment;

  void initialize_flags();

  void initialize_size_info();

  DEBUG_ONLY(void assert_flags();)

  DEBUG_ONLY(void assert_size_info();)

  // Compute max heap alignment.

  size_t compute_max_alignment();

  // Scale the base_size by NewRatio according to

  //     result = base_size / (NewRatio + 1)

  // and align by min_alignment()

  size_t scale_by_NewRatio_aligned(size_t base_size);

  // Bound the value by the given maximum minus the min_alignment.

  size_t bound_minus_alignment(size_t desired_size, size_t maximum_size);

 public:

  GenCollectorPolicy();

  // Accessors

  size_t min_young_size()     { return _min_young_size; }

  size_t initial_young_size() { return _initial_young_size; }

  size_t max_young_size()     { return _max_young_size; }

  size_t gen_alignment()      { return _gen_alignment; }

  size_t min_old_size()       { return _min_old_size; }

  size_t initial_old_size()   { return _initial_old_size; }

  size_t max_old_size()       { return _max_old_size; }

  size_t young_gen_size_lower_bound();

  size_t old_gen_size_lower_bound();

};

class MarkSweepPolicy : public GenCollectorPolicy {

 protected:

  void initialize_alignments();

 public:

  MarkSweepPolicy() {}

};

#endif // SHARE_GC_SHARED_COLLECTORPOLICY_HPP