Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2001, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.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.

   // resize_commit_uncommit() returns true if the pages were committed or

   // uncommitted

   bool 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

 };