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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).
 *
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 * 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_OBJECTMARKER_HPP
#define SHARE_GC_SHARED_OBJECTMARKER_HPP

#include "memory/allocation.hpp"
#include "oops/markWord.hpp"
#include "utilities/growableArray.hpp"

// ObjectMarker is used to support JVMTI for marking objects when walking the
// heap.
class ObjectMarker : public CHeapObj<mtInternal> {
protected:
  bool _needs_reset;
public:
  // initialize
  virtual bool init() = 0;
  // clean-up
  virtual void done() = 0;

  // mark an object if not yet marked.
  // return true if the oop is marked by this call
  virtual bool mark(oop o) = 0;
  // check if the object has been
  virtual bool marked(oop o) = 0;

  bool needs_reset() const      { return _needs_reset; }
  void set_needs_reset(bool v)  { _needs_reset = v; }
};

// Default implementation
class DefaultObjectMarker : public ObjectMarker {
 private:
  // saved headers
  GrowableArray<oop>* _saved_oop_stack;
  GrowableArray<markWord>* _saved_mark_stack;

 public:
  DefaultObjectMarker();
  bool init();
  void done();

  bool mark(oop o);
  bool marked(oop o);
};

#endif // SHARE_GC_SHARED_OBJECTMARKER_HPP