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_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP
26 #define SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP
27
28 #include "gc/shared/barrierSet.hpp"
29 #include "gc/shared/modRefBarrierSet.hpp"
30 #include "oops/klass.inline.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "oops/oop.hpp"
33
34 // count is number of array elements being written
35 void ModRefBarrierSet::write_ref_array(HeapWord* start, size_t count) {
36 HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
37 // In the case of compressed oops, start and end may potentially be misaligned;
38 // so we need to conservatively align the first downward (this is not
39 // strictly necessary for current uses, but a case of good hygiene and,
40 // if you will, aesthetics) and the second upward (this is essential for
41 // current uses) to a HeapWord boundary, so we mark all cards overlapping
42 // this write. If this evolves in the future to calling a
43 // logging barrier of narrow oop granularity, like the pre-barrier for G1
44 // (mentioned here merely by way of example), we will need to change this
45 // interface, so it is "exactly precise" (if i may be allowed the adverbial
46 // redundancy for emphasis) and does not include narrow oop slots not
47 // included in the original write interval.
48 HeapWord* aligned_start = align_down(start, HeapWordSize);
49 HeapWord* aligned_end = align_up (end, HeapWordSize);
50 // If compressed oops were not being used, these should already be aligned
51 assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
52 "Expected heap word alignment of start and end");
53 write_ref_array_work(MemRegion(aligned_start, aligned_end));
54 }
55
56 template <DecoratorSet decorators, typename BarrierSetT>
57 template <typename T>
58 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
59 oop_store_in_heap(T* addr, oop value) {
60 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
61 bs->template write_ref_field_pre<decorators>(addr);
62 Raw::oop_store(addr, value);
63 bs->template write_ref_field_post<decorators>(addr, value);
64 }
65
66 template <DecoratorSet decorators, typename BarrierSetT>
67 template <typename T>
68 inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
69 oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
70 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
71 bs->template write_ref_field_pre<decorators>(addr);
72 oop result = Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
73 if (result == compare_value) {
74 bs->template write_ref_field_post<decorators>(addr, new_value);
75 }
76 return result;
77 }
78
79 template <DecoratorSet decorators, typename BarrierSetT>
80 template <typename T>
81 inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
82 oop_atomic_xchg_in_heap(oop new_value, T* addr) {
83 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
84 bs->template write_ref_field_pre<decorators>(addr);
85 oop result = Raw::oop_atomic_xchg(new_value, addr);
86 bs->template write_ref_field_post<decorators>(addr, new_value);
87 return result;
88 }
89
90 template <DecoratorSet decorators, typename BarrierSetT>
91 template <typename T>
92 inline bool ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
93 oop_arraycopy_in_heap(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {
94 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
95
96 if (!HasDecorator<decorators, ARRAYCOPY_CHECKCAST>::value) {
97 // Optimized covariant case
98 bs->write_ref_array_pre(dst, length,
99 HasDecorator<decorators, AS_DEST_NOT_INITIALIZED>::value);
100 Raw::oop_arraycopy(src_obj, dst_obj, src, dst, length);
101 bs->write_ref_array((HeapWord*)dst, length);
102 } else {
103 Klass* bound = objArrayOop(dst_obj)->element_klass();
104 T* from = src;
105 T* end = from + length;
106 for (T* p = dst; from < end; from++, p++) {
107 T element = *from;
108 if (bound->is_instanceof_or_null(element)) {
109 bs->template write_ref_field_pre<decorators>(p);
110 *p = element;
111 } else {
112 // We must do a barrier to cover the partial copy.
113 const size_t pd = pointer_delta(p, dst, (size_t)heapOopSize);
114 // pointer delta is scaled to number of elements (length field in
115 // objArrayOop) which we assume is 32 bit.
116 assert(pd == (size_t)(int)pd, "length field overflow");
117 bs->write_ref_array((HeapWord*)dst, pd);
118 return false;
119 }
120 }
121 bs->write_ref_array((HeapWord*)dst, length);
122 }
123 return true;
124 }
125
126 template <DecoratorSet decorators, typename BarrierSetT>
127 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
128 clone_in_heap(oop src, oop dst, size_t size) {
129 Raw::clone(src, dst, size);
130 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
131 bs->write_region(MemRegion((HeapWord*)(void*)dst, size));
132 }
133
134 #endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP