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