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24 
25 #ifndef SHARE_GC_G1_G1BARRIERSET_INLINE_HPP
26 #define SHARE_GC_G1_G1BARRIERSET_INLINE_HPP
27 
28 #include "gc/g1/g1BarrierSet.hpp"
29 #include "gc/g1/g1CardTable.hpp"
30 #include "gc/shared/accessBarrierSupport.inline.hpp"
31 #include "oops/access.inline.hpp"
32 #include "oops/compressedOops.inline.hpp"
33 #include "oops/oop.hpp"
34 
35 template <DecoratorSet decorators, typename T>
write_ref_field_pre(T * field)36 inline void G1BarrierSet::write_ref_field_pre(T* field) {
37   if (HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value ||
38       HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
39     return;
40   }
41 
42   T heap_oop = RawAccess<MO_VOLATILE>::oop_load(field);
43   if (!CompressedOops::is_null(heap_oop)) {
44     enqueue(CompressedOops::decode_not_null(heap_oop));
45   }
46 }
47 
48 template <DecoratorSet decorators, typename T>
write_ref_field_post(T * field,oop new_val)49 inline void G1BarrierSet::write_ref_field_post(T* field, oop new_val) {
50   volatile CardValue* byte = _card_table->byte_for(field);
51   if (*byte != G1CardTable::g1_young_card_val()) {
52     // Take a slow path for cards in old
53     write_ref_field_post_slow(byte);
54   }
55 }
56 
enqueue_if_weak(DecoratorSet decorators,oop value)57 inline void G1BarrierSet::enqueue_if_weak(DecoratorSet decorators, oop value) {
58   assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
59   // Loading from a weak or phantom reference needs enqueueing, as
60   // the object may not have been reachable (part of the snapshot)
61   // when marking started.
62   const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
63   const bool peek              = (decorators & AS_NO_KEEPALIVE) != 0;
64   const bool needs_enqueue     = (!peek && !on_strong_oop_ref);
65 
66   if (needs_enqueue && value != NULL) {
67     enqueue(value);
68   }
69 }
70 
71 template <DecoratorSet decorators, typename BarrierSetT>
72 template <typename T>
73 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_load_not_in_heap(T * addr)74 oop_load_not_in_heap(T* addr) {
75   oop value = ModRef::oop_load_not_in_heap(addr);
76   enqueue_if_weak(decorators, value);
77   return value;
78 }
79 
80 template <DecoratorSet decorators, typename BarrierSetT>
81 template <typename T>
82 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_load_in_heap(T * addr)83 oop_load_in_heap(T* addr) {
84   oop value = ModRef::oop_load_in_heap(addr);
85   enqueue_if_weak(decorators, value);
86   return value;
87 }
88 
89 template <DecoratorSet decorators, typename BarrierSetT>
90 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_load_in_heap_at(oop base,ptrdiff_t offset)91 oop_load_in_heap_at(oop base, ptrdiff_t offset) {
92   oop value = ModRef::oop_load_in_heap_at(base, offset);
93   enqueue_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);
94   return value;
95 }
96 
97 template <DecoratorSet decorators, typename BarrierSetT>
98 template <typename T>
99 inline void G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_store_not_in_heap(T * addr,oop new_value)100 oop_store_not_in_heap(T* addr, oop new_value) {
101   // Apply SATB barriers for all non-heap references, to allow
102   // concurrent scanning of such references.
103   G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set());
104   bs->write_ref_field_pre<decorators>(addr);
105   Raw::oop_store(addr, new_value);
106 }
107 
108 #endif // SHARE_GC_G1_G1BARRIERSET_INLINE_HPP
109