1/*
2 * Copyright (c) 2001, 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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12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
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24
25#ifndef SHARE_GC_PARALLEL_PSMARKSWEEPDECORATOR_HPP
26#define SHARE_GC_PARALLEL_PSMARKSWEEPDECORATOR_HPP
27
28#include "gc/parallel/mutableSpace.hpp"
29
30//
31// A PSMarkSweepDecorator is used to add "ParallelScavenge" style mark sweep operations
32// to a MutableSpace.
33//
34
35class ObjectStartArray;
36
37class PSMarkSweepDecorator: public CHeapObj<mtGC> {
38 private:
39 static PSMarkSweepDecorator* _destination_decorator;
40
41 protected:
42 MutableSpace* _space;
43 ObjectStartArray* _start_array;
44 HeapWord* _first_dead;
45 HeapWord* _end_of_live;
46 HeapWord* _compaction_top;
47 size_t _allowed_dead_ratio;
48
49 bool insert_deadspace(size_t& allowed_deadspace_words, HeapWord* q,
50 size_t word_len);
51
52 public:
53 PSMarkSweepDecorator(MutableSpace* space, ObjectStartArray* start_array,
54 size_t allowed_dead_ratio) :
55 _space(space),
56 _start_array(start_array),
57 _first_dead(NULL),
58 _end_of_live(NULL),
59 _compaction_top(NULL),
60 _allowed_dead_ratio(allowed_dead_ratio) { }
61
62 // During a compacting collection, we need to collapse objects into
63 // spaces in a given order. We want to fill space A, space B, and so
64 // on. The code that controls that order is in the following methods.
65 static void set_destination_decorator_tenured();
66 static void advance_destination_decorator();
67 static PSMarkSweepDecorator* destination_decorator();
68
69 // Accessors
70 MutableSpace* space() { return _space; }
71 ObjectStartArray* start_array() { return _start_array; }
72
73 HeapWord* compaction_top() { return _compaction_top; }
74 void set_compaction_top(HeapWord* value) { _compaction_top = value; }
75
76 size_t allowed_dead_ratio() { return _allowed_dead_ratio; }
77 void set_allowed_dead_ratio(size_t value) { _allowed_dead_ratio = value; }
78
79 // Work methods
80 void adjust_pointers();
81 void precompact();
82 void compact(bool mangle_free_space);
83};
84
85#endif // SHARE_GC_PARALLEL_PSMARKSWEEPDECORATOR_HPP
86