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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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_VM_GC_G1_G1SATBCARDTABLEMODREFBS_HPP
#define SHARE_VM_GC_G1_G1SATBCARDTABLEMODREFBS_HPP

#include "gc/g1/g1RegionToSpaceMapper.hpp"
#include "gc/shared/cardTableModRefBS.hpp"
#include "memory/memRegion.hpp"
#include "oops/oop.hpp"
#include "utilities/macros.hpp"

class DirtyCardQueueSet;
class G1SATBCardTableLoggingModRefBS;
class CardTable;
class G1CardTable;

// This barrier is specialized to use a logging barrier to support
// snapshot-at-the-beginning marking.

class G1SATBCardTableModRefBS: public CardTableModRefBS {
  friend class VMStructs;
protected:
  G1SATBCardTableModRefBS(G1CardTable* table, const BarrierSet::FakeRtti& fake_rtti);
  ~G1SATBCardTableModRefBS() { }

public:
  // Add "pre_val" to a set of objects that may have been disconnected from the
  // pre-marking object graph.
  static void enqueue(oop pre_val);

  static void enqueue_if_weak_or_archive(DecoratorSet decorators, oop value);

  template <class T> void write_ref_array_pre_work(T* dst, int count);
  virtual void write_ref_array_pre(oop* dst, int count, bool dest_uninitialized);
  virtual void write_ref_array_pre(narrowOop* dst, int count, bool dest_uninitialized);

  template <DecoratorSet decorators, typename T>
  void write_ref_field_pre(T* field);
};

template<>
struct BarrierSet::GetName<G1SATBCardTableModRefBS> {
  static const BarrierSet::Name value = BarrierSet::G1SATBCT;
};

template<>
struct BarrierSet::GetType<BarrierSet::G1SATBCT> {
  typedef G1SATBCardTableModRefBS type;
};

// Adds card-table logging to the post-barrier.
// Usual invariant: all dirty cards are logged in the DirtyCardQueueSet.
class G1SATBCardTableLoggingModRefBS: public G1SATBCardTableModRefBS {
 private:
  DirtyCardQueueSet& _dcqs;

 public:
  G1SATBCardTableLoggingModRefBS(G1CardTable* card_table);

  // NB: if you do a whole-heap invalidation, the "usual invariant" defined
  // above no longer applies.
  void invalidate(MemRegion mr);

  void write_region(MemRegion mr)         { invalidate(mr); }
  void write_ref_array_work(MemRegion mr) { invalidate(mr); }

  template <DecoratorSet decorators, typename T>
  void write_ref_field_post(T* field, oop new_val);
  void write_ref_field_post_slow(volatile jbyte* byte);

  virtual void on_thread_attach(JavaThread* thread);
  virtual void on_thread_detach(JavaThread* thread);

  // Callbacks for runtime accesses.
  template <DecoratorSet decorators, typename BarrierSetT = G1SATBCardTableLoggingModRefBS>
  class AccessBarrier: public ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> {
    typedef ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> ModRef;
    typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;

  public:
    // Needed for loads on non-heap weak references
    template <typename T>
    static oop oop_load_not_in_heap(T* addr);

    // Needed for non-heap stores
    template <typename T>
    static void oop_store_not_in_heap(T* addr, oop new_value);

    // Needed for weak references
    static oop oop_load_in_heap_at(oop base, ptrdiff_t offset);

    // Defensive: will catch weak oops at addresses in heap
    template <typename T>
    static oop oop_load_in_heap(T* addr);
  };
};

template<>
struct BarrierSet::GetName<G1SATBCardTableLoggingModRefBS> {
  static const BarrierSet::Name value = BarrierSet::G1SATBCTLogging;
};

template<>
struct BarrierSet::GetType<BarrierSet::G1SATBCTLogging> {
  typedef G1SATBCardTableLoggingModRefBS type;
};

#endif // SHARE_VM_GC_G1_G1SATBCARDTABLEMODREFBS_HPP