dfsClosure.hpp

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#ifndef SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP
#define SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP

#include "jfr/leakprofiler/utilities/unifiedOopRef.hpp"
#include "memory/iterator.hpp"

class BitSet;
class Edge;
class EdgeStore;
class EdgeQueue;

// Class responsible for iterating the heap depth-first
class DFSClosure : public BasicOopIterateClosure {
 private:
  // max dfs depth should not exceed size of stack
  static const size_t max_dfs_depth = 4000;
  static UnifiedOopRef _reference_stack[max_dfs_depth];

  EdgeStore* _edge_store;
  BitSet* _mark_bits;
  const Edge*_start_edge;
  size_t _max_depth;
  size_t _depth;
  bool _ignore_root_set;

  DFSClosure(EdgeStore* edge_store, BitSet* mark_bits, const Edge* start_edge);

  void add_chain();
  void closure_impl(UnifiedOopRef reference, const oop pointee);

 public:
  virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS_EXCEPT_REFERENT; }

  static void find_leaks_from_edge(EdgeStore* edge_store, BitSet* mark_bits, const Edge* start_edge);
  static void find_leaks_from_root_set(EdgeStore* edge_store, BitSet* mark_bits);
  void do_root(UnifiedOopRef ref);

  virtual void do_oop(oop* ref);
  virtual void do_oop(narrowOop* ref);
};

#endif // SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP