1/*
2 * Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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24
25#ifndef SHARE_JFR_LEAKPROFILER_CHAINS_BFSCLOSURE_HPP
26#define SHARE_JFR_LEAKPROFILER_CHAINS_BFSCLOSURE_HPP
27
28#include "memory/iterator.hpp"
29
30class BitSet;
31class Edge;
32class EdgeStore;
33class EdgeQueue;
34
35// Class responsible for iterating the heap breadth-first
36class BFSClosure : public BasicOopIterateClosure {
37 private:
38 EdgeQueue* _edge_queue;
39 EdgeStore* _edge_store;
40 BitSet* _mark_bits;
41 const Edge* _current_parent;
42 mutable size_t _current_frontier_level;
43 mutable size_t _next_frontier_idx;
44 mutable size_t _prev_frontier_idx;
45 size_t _dfs_fallback_idx;
46 bool _use_dfs;
47
48 void log_completed_frontier() const;
49 void log_dfs_fallback() const;
50
51 bool is_complete() const;
52 void step_frontier() const;
53
54 void closure_impl(const oop* reference, const oop pointee);
55 void add_chain(const oop* reference, const oop pointee);
56 void dfs_fallback();
57
58 void iterate(const Edge* parent);
59 void process(const oop* reference, const oop pointee);
60
61 void process_root_set();
62 void process_queue();
63
64 public:
65 BFSClosure(EdgeQueue* edge_queue, EdgeStore* edge_store, BitSet* mark_bits);
66 void process();
67 void do_root(const oop* ref);
68
69 virtual void do_oop(oop* ref);
70 virtual void do_oop(narrowOop* ref);
71};
72
73#endif // SHARE_JFR_LEAKPROFILER_CHAINS_BFSCLOSURE_HPP
74