/*

 * Copyright 2001-2008 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.

 *

 */

class MutableSpace;

class ObjectStartArray;

class PSPromotionManager;

class GCTaskQueue;

class CardTableExtension : public CardTableModRefBS {

 private:

  // Support methods for resizing the card table.

  void resize_commit_uncommit(int changed_region, MemRegion new_region);

  void resize_update_card_table_entries(int changed_region,

                                        MemRegion new_region);

  void resize_update_committed_table(int changed_region, MemRegion new_region);

  void resize_update_covered_table(int changed_region, MemRegion new_region);

 protected:

  static void verify_all_young_refs_precise_helper(MemRegion mr);

 public:

  enum ExtendedCardValue {

    youngergen_card   = CardTableModRefBS::CT_MR_BS_last_reserved + 1,

    verify_card       = CardTableModRefBS::CT_MR_BS_last_reserved + 5

  };

  CardTableExtension(MemRegion whole_heap, int max_covered_regions) :

    CardTableModRefBS(whole_heap, max_covered_regions) { }

  // Too risky for the 4/10/02 putback

  // BarrierSet::Name kind() { return BarrierSet::CardTableExtension; }

  // Scavenge support

  void scavenge_contents(ObjectStartArray* start_array,

                         MutableSpace* sp,

                         HeapWord* space_top,

                         PSPromotionManager* pm);

  void scavenge_contents_parallel(ObjectStartArray* start_array,

                                  MutableSpace* sp,

                                  HeapWord* space_top,

                                  PSPromotionManager* pm,

                                  uint stripe_number);

  // Verification

  static void verify_all_young_refs_imprecise();

  static void verify_all_young_refs_precise();

  bool addr_is_marked_imprecise(void *addr);

  bool addr_is_marked_precise(void *addr);

  void set_card_newgen(void* addr)   { jbyte* p = byte_for(addr); *p = verify_card; }

  // Testers for entries

  static bool card_is_dirty(int value)      { return value == dirty_card; }

  static bool card_is_newgen(int value)     { return value == youngergen_card; }

  static bool card_is_clean(int value)      { return value == clean_card; }

  static bool card_is_verify(int value)     { return value == verify_card; }

  // Card marking

  void inline_write_ref_field_gc(void* field, oop new_val) {

    jbyte* byte = byte_for(field);

    *byte = youngergen_card;

  }

  // Adaptive size policy support

  // Allows adjustment of the base and size of the covered regions

  void resize_covered_region(MemRegion new_region);

  // Finds the covered region to resize based on the start address

  // of the covered regions.

  void resize_covered_region_by_start(MemRegion new_region);

  // Finds the covered region to resize based on the end address

  // of the covered regions.

  void resize_covered_region_by_end(int changed_region, MemRegion new_region);

  // Finds the lowest start address of a covered region that is

  // previous (i.e., lower index) to the covered region with index "ind".

  HeapWord* lowest_prev_committed_start(int ind) const;

#ifdef ASSERT

  bool is_valid_card_address(jbyte* addr) {

    return (addr >= _byte_map) && (addr < _byte_map + _byte_map_size);

  }

#endif // ASSERT

};