1 /*
2 * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
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23 */
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/compressedOops.inline.hpp"
31 #include "oops/klass.inline.hpp"
32 #include "oops/objArrayOop.hpp"
33 #include "oops/oop.hpp"
34
35 // count is number of array elements being written
write_ref_array(HeapWord * start,size_t count)36 void ModRefBarrierSet::write_ref_array(HeapWord* start, size_t count) {
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>::
oop_store_in_heap(T * addr,oop value)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>::
oop_atomic_cmpxchg_in_heap(oop new_value,T * addr,oop compare_value)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>::
oop_atomic_xchg_in_heap(oop new_value,T * addr)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>::
oop_arraycopy_in_heap(arrayOop src_obj,size_t src_offset_in_bytes,T * src_raw,arrayOop dst_obj,size_t dst_offset_in_bytes,T * dst_raw,size_t length)94 oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
95 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
96 size_t length) {
97 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
98
99 src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
100 dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
101
102 if (!HasDecorator<decorators, ARRAYCOPY_CHECKCAST>::value) {
103 // Optimized covariant case
104 bs->write_ref_array_pre(dst_raw, length,
105 HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value);
106 Raw::oop_arraycopy(NULL, 0, src_raw, NULL, 0, dst_raw, length);
107 bs->write_ref_array((HeapWord*)dst_raw, length);
108 } else {
109 assert(dst_obj != NULL, "better have an actual oop");
110 Klass* bound = objArrayOop(dst_obj)->element_klass();
111 T* from = const_cast<T*>(src_raw);
112 T* end = from + length;
113 for (T* p = dst_raw; from < end; from++, p++) {
114 T element = *from;
115 if (oopDesc::is_instanceof_or_null(CompressedOops::decode(element), bound)) {
116 bs->template write_ref_field_pre<decorators>(p);
117 *p = element;
118 } else {
119 // We must do a barrier to cover the partial copy.
120 const size_t pd = pointer_delta(p, dst_raw, (size_t)heapOopSize);
121 // pointer delta is scaled to number of elements (length field in
122 // objArrayOop) which we assume is 32 bit.
123 assert(pd == (size_t)(int)pd, "length field overflow");
124 bs->write_ref_array((HeapWord*)dst_raw, pd);
125 return false;
126 }
127 }
128 bs->write_ref_array((HeapWord*)dst_raw, length);
129 }
130 return true;
131 }
132
133 template <DecoratorSet decorators, typename BarrierSetT>
134 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
clone_in_heap(oop src,oop dst,size_t size)135 clone_in_heap(oop src, oop dst, size_t size) {
136 Raw::clone(src, dst, size);
137 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
138 bs->write_region(MemRegion((HeapWord*)(void*)dst, size));
139 }
140
141 #endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP
142