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24 
25 #ifndef SHARE_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP
26 #define SHARE_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP
27 
28 #include "jfr/leakprofiler/chains/edge.hpp"
29 #include "jfr/utilities/jfrHashtable.hpp"
30 #include "memory/allocation.hpp"
31 
32 typedef u8 traceid;
33 
34 class StoredEdge : public Edge {
35  private:
36   mutable traceid _gc_root_id;
37   size_t _skip_length;
38 
39  public:
40   StoredEdge();
41   StoredEdge(const Edge* parent, const oop* reference);
42   StoredEdge(const Edge& edge);
43   StoredEdge(const StoredEdge& edge);
44   void operator=(const StoredEdge& edge);
45 
gc_root_id() const46   traceid gc_root_id() const { return _gc_root_id; }
set_gc_root_id(traceid root_id) const47   void set_gc_root_id(traceid root_id) const { _gc_root_id = root_id; }
48 
is_skip_edge() const49   bool is_skip_edge() const { return _skip_length != 0; }
skip_length() const50   size_t skip_length() const { return _skip_length; }
set_skip_length(size_t length)51   void set_skip_length(size_t length) { _skip_length = length; }
52 
set_parent(const Edge * edge)53   void set_parent(const Edge* edge) { this->_parent = edge; }
54 
parent() const55   StoredEdge* parent() const {
56     return const_cast<StoredEdge*>(static_cast<const StoredEdge*>(Edge::parent()));
57   }
58 };
59 
60 class EdgeStore : public CHeapObj<mtTracing> {
61   typedef HashTableHost<StoredEdge, traceid, JfrHashtableEntry, EdgeStore> EdgeHashTable;
62   typedef EdgeHashTable::HashEntry EdgeEntry;
63   template <typename,
64             typename,
65             template<typename, typename> class,
66             typename,
67             size_t>
68   friend class HashTableHost;
69   friend class EventEmitter;
70   friend class ObjectSampleWriter;
71   friend class ObjectSampleCheckpoint;
72  private:
73   static traceid _edge_id_counter;
74   EdgeHashTable* _edges;
75 
76   // Hash table callbacks
77   void on_link(EdgeEntry* entry);
78   bool on_equals(uintptr_t hash, const EdgeEntry* entry);
79   void on_unlink(EdgeEntry* entry);
80 
81   StoredEdge* get(const oop* reference) const;
82   StoredEdge* put(const oop* reference);
83   traceid gc_root_id(const Edge* edge) const;
84 
85   bool put_edges(StoredEdge** previous, const Edge** current, size_t length);
86   bool put_skip_edge(StoredEdge** previous, const Edge** current, size_t distance_to_root);
87   void put_chain_epilogue(StoredEdge* leak_context_edge, const Edge* root) const;
88 
89   StoredEdge* associate_leak_context_with_candidate(const Edge* edge);
90   void store_gc_root_id_in_leak_context_edge(StoredEdge* leak_context_edge, const Edge* root) const;
91   StoredEdge* link_new_edge(StoredEdge** previous, const Edge** current);
92   void link_with_existing_chain(const StoredEdge* current_stored, StoredEdge** previous, size_t previous_length);
93 
94   template <typename T>
iterate(T & functor) const95   void iterate(T& functor) const { _edges->iterate_value<T>(functor); }
96 
97   DEBUG_ONLY(bool contains(const oop* reference) const;)
98 
99  public:
100   EdgeStore();
101   ~EdgeStore();
102 
103   bool is_empty() const;
104   traceid get_id(const Edge* edge) const;
105   void put_chain(const Edge* chain, size_t length);
106 };
107 
108 #endif // SHARE_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP
109