8198949_arraycopy
36 // As it currently stands, this barrier is *imprecise*: when a ref field in
37 // an object "o" is modified, the card table entry for the card containing
38 // the head of "o" is dirtied, not necessarily the card containing the
39 // modified field itself. For object arrays, however, the barrier *is*
40 // precise; only the card containing the modified element is dirtied.
41 // Closures used to scan dirty cards should take these
42 // considerations into account.
43
44 class CardTableModRefBS: public ModRefBarrierSet {
45 // Some classes get to look at some private stuff.
46 friend class VMStructs;
47 protected:
48
49 // Used in support of ReduceInitialCardMarks; only consulted if COMPILER2
50 // or INCLUDE_JVMCI is being used
51 bool _defer_initial_card_mark;
52 CardTable* _card_table;
53
54 CardTableModRefBS(CardTable* card_table, const BarrierSet::FakeRtti& fake_rtti);
55
56 public:
57 CardTableModRefBS(CardTable* card_table);
58 ~CardTableModRefBS();
59
60 CardTable* card_table() const { return _card_table; }
61
62 virtual void initialize();
63
64 void write_region(MemRegion mr) {
65 invalidate(mr);
66 }
67
68 protected:
69 void write_ref_array_work(MemRegion mr);
70
71 public:
72 // Record a reference update. Note that these versions are precise!
73 // The scanning code has to handle the fact that the write barrier may be
74 // either precise or imprecise. We make non-virtual inline variants of
75 // these functions here for performance.
76 template <DecoratorSet decorators, typename T>
77 void write_ref_field_post(T* field, oop newVal);
78
79 virtual void invalidate(MemRegion mr);
80
81 // ReduceInitialCardMarks
82 void initialize_deferred_card_mark_barriers();
83
84 // If the CollectedHeap was asked to defer a store barrier above,
85 // this informs it to flush such a deferred store barrier to the
86 // remembered set.
87 void flush_deferred_card_mark_barrier(JavaThread* thread);
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36 // As it currently stands, this barrier is *imprecise*: when a ref field in
37 // an object "o" is modified, the card table entry for the card containing
38 // the head of "o" is dirtied, not necessarily the card containing the
39 // modified field itself. For object arrays, however, the barrier *is*
40 // precise; only the card containing the modified element is dirtied.
41 // Closures used to scan dirty cards should take these
42 // considerations into account.
43
44 class CardTableModRefBS: public ModRefBarrierSet {
45 // Some classes get to look at some private stuff.
46 friend class VMStructs;
47 protected:
48
49 // Used in support of ReduceInitialCardMarks; only consulted if COMPILER2
50 // or INCLUDE_JVMCI is being used
51 bool _defer_initial_card_mark;
52 CardTable* _card_table;
53
54 CardTableModRefBS(CardTable* card_table, const BarrierSet::FakeRtti& fake_rtti);
55
56 BarrierSetCodeGen* make_code_gen();
57
58 public:
59 CardTableModRefBS(CardTable* card_table);
60 ~CardTableModRefBS();
61
62 CardTable* card_table() const { return _card_table; }
63
64 virtual void initialize();
65
66 void write_region(MemRegion mr) {
67 invalidate(mr);
68 }
69
70 void write_ref_array_work(MemRegion mr);
71
72 public:
73 // Record a reference update. Note that these versions are precise!
74 // The scanning code has to handle the fact that the write barrier may be
75 // either precise or imprecise. We make non-virtual inline variants of
76 // these functions here for performance.
77 template <DecoratorSet decorators, typename T>
78 void write_ref_field_post(T* field, oop newVal);
79
80 virtual void invalidate(MemRegion mr);
81
82 // ReduceInitialCardMarks
83 void initialize_deferred_card_mark_barriers();
84
85 // If the CollectedHeap was asked to defer a store barrier above,
86 // this informs it to flush such a deferred store barrier to the
87 // remembered set.
88 void flush_deferred_card_mark_barrier(JavaThread* thread);
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