1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24
25#ifndef SHARE_GC_SHARED_MODREFBARRIERSET_HPP
26#define SHARE_GC_SHARED_MODREFBARRIERSET_HPP
27
28#include "gc/shared/barrierSet.hpp"
29#include "memory/memRegion.hpp"
30
31class Klass;
32
33class ModRefBarrierSet: public BarrierSet {
34protected:
35 ModRefBarrierSet(BarrierSetAssembler* barrier_set_assembler,
36 BarrierSetC1* barrier_set_c1,
37 BarrierSetC2* barrier_set_c2,
38 const BarrierSet::FakeRtti& fake_rtti)
39 : BarrierSet(barrier_set_assembler,
40 barrier_set_c1,
41 barrier_set_c2,
42 NULL /* barrier_set_nmethod */,
43 fake_rtti.add_tag(BarrierSet::ModRef)) { }
44 ~ModRefBarrierSet() { }
45
46public:
47 template <DecoratorSet decorators, typename T>
48 inline void write_ref_field_pre(T* addr) {}
49
50 template <DecoratorSet decorators, typename T>
51 inline void write_ref_field_post(T *addr, oop new_value) {}
52
53 // Causes all refs in "mr" to be assumed to be modified.
54 virtual void invalidate(MemRegion mr) = 0;
55 virtual void write_region(MemRegion mr) = 0;
56
57 // Operations on arrays, or general regions (e.g., for "clone") may be
58 // optimized by some barriers.
59
60 // Below length is the # array elements being written
61 virtual void write_ref_array_pre(oop* dst, size_t length,
62 bool dest_uninitialized = false) {}
63 virtual void write_ref_array_pre(narrowOop* dst, size_t length,
64 bool dest_uninitialized = false) {}
65 // Below count is the # array elements being written, starting
66 // at the address "start", which may not necessarily be HeapWord-aligned
67 inline void write_ref_array(HeapWord* start, size_t count);
68
69 protected:
70 virtual void write_ref_array_work(MemRegion mr) = 0;
71
72 public:
73 // The ModRef abstraction introduces pre and post barriers
74 template <DecoratorSet decorators, typename BarrierSetT>
75 class AccessBarrier: public BarrierSet::AccessBarrier<decorators, BarrierSetT> {
76 typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;
77
78 public:
79 template <typename T>
80 static void oop_store_in_heap(T* addr, oop value);
81 template <typename T>
82 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value);
83 template <typename T>
84 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr);
85
86 template <typename T>
87 static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
88 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
89 size_t length);
90
91 static void clone_in_heap(oop src, oop dst, size_t size);
92
93 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
94 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);
95 }
96
97 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
98 return oop_atomic_xchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset));
99 }
100
101 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
102 return oop_atomic_cmpxchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value);
103 }
104 };
105};
106
107template<>
108struct BarrierSet::GetName<ModRefBarrierSet> {
109 static const BarrierSet::Name value = BarrierSet::ModRef;
110};
111
112#endif // SHARE_GC_SHARED_MODREFBARRIERSET_HPP
113