/*

 * Copyright 2005-2009 Sun Microsystems, Inc.  All Rights Reserved.

 * 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.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

// Move to some global location

#define HAS_BEEN_MOVED 0x1501d01d

// End move to some global location

class MutableSpace;

class PSOldGen;

class ParCompactionManager;

class ObjectStartArray;

class ParallelCompactData;

class ParMarkBitMap;

class ParCompactionManager : public CHeapObj {

  friend class ParallelTaskTerminator;

  friend class ParMarkBitMap;

  friend class PSParallelCompact;

  friend class StealRegionCompactionTask;

  friend class UpdateAndFillClosure;

  friend class RefProcTaskExecutor;

 public:

// ------------------------  Don't putback if not needed

  // Actions that the compaction manager should take.

  enum Action {

    Update,

    Copy,

    UpdateAndCopy,

    CopyAndUpdate,

    VerifyUpdate,

    ResetObjects,

    NotValid

  };

// ------------------------  End don't putback if not needed

 private:

  // 32-bit:  4K * 8 = 32KiB; 64-bit:  8K * 16 = 128KiB

  #define OBJARRAY_QUEUE_SIZE (1 << NOT_LP64(12) LP64_ONLY(13))

  typedef GenericTaskQueue<ObjArrayTask, OBJARRAY_QUEUE_SIZE> ObjArrayTaskQueue;

  typedef GenericTaskQueueSet<ObjArrayTaskQueue> ObjArrayTaskQueueSet;

  #undef OBJARRAY_QUEUE_SIZE

  static ParCompactionManager** _manager_array;

  static OopTaskQueueSet*       _stack_array;

  static ObjArrayTaskQueueSet*  _objarray_queues;

  static ObjectStartArray*      _start_array;

  static RegionTaskQueueSet*    _region_array;

  static PSOldGen*              _old_gen;

private:

  OopTaskQueue                  _marking_stack;

  GrowableArray<oop>*           _overflow_stack;

  typedef GrowableArray<ObjArrayTask> ObjArrayOverflowStack;

  ObjArrayTaskQueue             _objarray_queue;

  ObjArrayOverflowStack*        _objarray_overflow_stack;

  // Is there a way to reuse the _marking_stack for the

  // saving empty regions?  For now just create a different

  // type of TaskQueue.

#ifdef USE_RegionTaskQueueWithOverflow

  RegionTaskQueueWithOverflow   _region_stack;

#else

  RegionTaskQueue               _region_stack;

  GrowableArray<size_t>*        _region_overflow_stack;

#endif

#if 1  // does this happen enough to need a per thread stack?

  GrowableArray<Klass*>*        _revisit_klass_stack;

  GrowableArray<DataLayout*>*   _revisit_mdo_stack;

#endif

  static ParMarkBitMap* _mark_bitmap;

  Action _action;

  static PSOldGen* old_gen()             { return _old_gen; }

  static ObjectStartArray* start_array() { return _start_array; }

  static OopTaskQueueSet* stack_array()  { return _stack_array; }

  static void initialize(ParMarkBitMap* mbm);

 protected:

  // Array of tasks.  Needed by the ParallelTaskTerminator.

  static RegionTaskQueueSet* region_array()      { return _region_array; }

  OopTaskQueue*  marking_stack()                 { return &_marking_stack; }

  GrowableArray<oop>* overflow_stack()           { return _overflow_stack; }

#ifdef USE_RegionTaskQueueWithOverflow

  RegionTaskQueueWithOverflow* region_stack()    { return &_region_stack; }

#else

  RegionTaskQueue*  region_stack()               { return &_region_stack; }

  GrowableArray<size_t>* region_overflow_stack() {

    return _region_overflow_stack;

  }

#endif

  // Pushes onto the marking stack.  If the marking stack is full,

  // pushes onto the overflow stack.

  void stack_push(oop obj);

  // Do not implement an equivalent stack_pop.  Deal with the

  // marking stack and overflow stack directly.

  // Pushes onto the region stack.  If the region stack is full,

  // pushes onto the region overflow stack.

  void region_stack_push(size_t region_index);

public:

  Action action() { return _action; }

  void set_action(Action v) { _action = v; }

  inline static ParCompactionManager* manager_array(int index);

  ParCompactionManager();

  ~ParCompactionManager();

  void allocate_stacks();

  void deallocate_stacks();

  ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }

  // Take actions in preparation for a compaction.

  static void reset();

  // void drain_stacks();

  bool should_update();

  bool should_copy();

  bool should_verify_only();

  bool should_reset_only();

#if 1

  // Probably stays as a growable array

  GrowableArray<Klass*>* revisit_klass_stack() { return _revisit_klass_stack; }

  GrowableArray<DataLayout*>* revisit_mdo_stack() { return _revisit_mdo_stack; }

#endif

  // Save oop for later processing.  Must not fail.

  void save_for_scanning(oop m);

  // Get a oop for scanning.  If returns null, no oop were found.

  oop retrieve_for_scanning();

  inline void push_objarray(oop obj, size_t index);

  // Save region for later processing.  Must not fail.

  void save_for_processing(size_t region_index);

  // Get a region for processing.  If returns null, no region were found.

  bool retrieve_for_processing(size_t& region_index);

  // Access function for compaction managers

  static ParCompactionManager* gc_thread_compaction_manager(int index);

  static bool steal(int queue_num, int* seed, Task& t) {

    return stack_array()->steal(queue_num, seed, t);

  }

  static bool steal_objarray(int queue_num, int* seed, ObjArrayTask& t) {

    return _objarray_queues->steal(queue_num, seed, t);

  }

  static bool steal(int queue_num, int* seed, RegionTask& t) {

    return region_array()->steal(queue_num, seed, t);

  }

  // Process tasks remaining on any marking stack

  void follow_marking_stacks();

  inline bool marking_stacks_empty() const;

  // Process tasks remaining on any stack

  void drain_region_stacks();

  // Process tasks remaining on any stack

  void drain_region_overflow_stack();

  // Debugging support

#ifdef ASSERT

  bool stacks_have_been_allocated();

#endif

};

inline ParCompactionManager* ParCompactionManager::manager_array(int index) {

  assert(_manager_array != NULL, "access of NULL manager_array");

  assert(index >= 0 && index <= (int)ParallelGCThreads,

    "out of range manager_array access");

  return _manager_array[index];

}

bool ParCompactionManager::marking_stacks_empty() const {

  return _marking_stack.size() == 0 && _overflow_stack->is_empty() &&

    _objarray_queue.size() == 0 && _objarray_overflow_stack->is_empty();

}