psMarkSweepDecorator.hpp revision 8413:92457dfb91bd 
1/*
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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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24
25#ifndef SHARE_VM_GC_PARALLEL_PSMARKSWEEPDECORATOR_HPP
26#define SHARE_VM_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), _start_array(start_array),
56    _allowed_dead_ratio(allowed_dead_ratio) { }
57
58  // During a compacting collection, we need to collapse objects into
59  // spaces in a given order. We want to fill space A, space B, and so
60  // on. The code that controls that order is in the following methods.
61  static void set_destination_decorator_tenured();
62  static void advance_destination_decorator();
63  static PSMarkSweepDecorator* destination_decorator();
64
65  // Accessors
66  MutableSpace* space()                     { return _space; }
67  ObjectStartArray* start_array()           { return _start_array; }
68
69  HeapWord* compaction_top()                { return _compaction_top; }
70  void set_compaction_top(HeapWord* value)  { _compaction_top = value; }
71
72  size_t allowed_dead_ratio()               { return _allowed_dead_ratio; }
73  void set_allowed_dead_ratio(size_t value) { _allowed_dead_ratio = value; }
74
75  // Work methods
76  void adjust_pointers();
77  void precompact();
78  void compact(bool mangle_free_space);
79};
80
81#endif // SHARE_VM_GC_PARALLEL_PSMARKSWEEPDECORATOR_HPP
82