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_CARDTABLEBARRIERSET_INLINE_HPP
26 #define SHARE_GC_SHARED_CARDTABLEBARRIERSET_INLINE_HPP
27
28 #include "gc/shared/cardTableBarrierSet.hpp"
29
30 #include "gc/shared/barrierSet.hpp"
31 #include "gc/shared/cardTable.hpp"
32 #include "oops/compressedOops.inline.hpp"
33 #include "oops/inlineKlass.inline.hpp"
34 #include "oops/layoutKind.hpp"
35 #include "oops/objArrayOop.hpp"
36 #include "oops/oop.hpp"
37 #include "utilities/debug.hpp"
38
39 template <DecoratorSet decorators, typename T>
40 inline void CardTableBarrierSet::write_ref_field_post(T* field) {
41 volatile CardValue* byte = card_table()->byte_for(field);
42 *byte = CardTable::dirty_card_val();
43 }
44
45 class Klass;
46
47 // count is number of array elements being written
48 void CardTableBarrierSet::write_ref_array(HeapWord* start, size_t count) {
49 HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
50 // In the case of compressed oops, start and end may potentially be misaligned;
51 // so we need to conservatively align the first downward (this is not
52 // strictly necessary for current uses, but a case of good hygiene and,
53 // if you will, aesthetics) and the second upward (this is essential for
54 // current uses) to a HeapWord boundary, so we mark all cards overlapping
55 // this write. If this evolves in the future to calling a
56 // logging barrier of narrow oop granularity, like the pre-barrier for G1
57 // (mentioned here merely by way of example), we will need to change this
58 // interface, so it is "exactly precise" (if i may be allowed the adverbial
59 // redundancy for emphasis) and does not include narrow oop slots not
60 // included in the original write interval.
61 HeapWord* aligned_start = align_down(start, HeapWordSize);
62 HeapWord* aligned_end = align_up (end, HeapWordSize);
63 // If compressed oops were not being used, these should already be aligned
64 assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
65 "Expected heap word alignment of start and end");
66 write_region(MemRegion(aligned_start, aligned_end));
67 }
68
69 template <DecoratorSet decorators, typename BarrierSetT>
70 template <typename T>
71 inline void CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
72 oop_store_in_heap(T* addr, oop value) {
73 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
74 bs->template write_ref_field_pre<decorators>(addr);
75 Raw::oop_store(addr, value);
76 bs->template write_ref_field_post<decorators>(addr);
77 }
78
79 template <DecoratorSet decorators, typename BarrierSetT>
80 template <typename T>
81 inline oop CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
82 oop_atomic_cmpxchg_in_heap(T* addr, oop compare_value, oop new_value) {
83 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
84 bs->template write_ref_field_pre<decorators>(addr);
85 oop result = Raw::oop_atomic_cmpxchg(addr, compare_value, new_value);
86 if (result == compare_value) {
87 bs->template write_ref_field_post<decorators>(addr);
88 }
89 return result;
90 }
91
92 template <DecoratorSet decorators, typename BarrierSetT>
93 template <typename T>
94 inline oop CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
95 oop_atomic_xchg_in_heap(T* addr, oop new_value) {
96 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
97 bs->template write_ref_field_pre<decorators>(addr);
98 oop result = Raw::oop_atomic_xchg(addr, new_value);
99 bs->template write_ref_field_post<decorators>(addr);
100 return result;
101 }
102
103 template <DecoratorSet decorators, typename BarrierSetT>
104 template <typename T>
105 inline void CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
106 oop_arraycopy_partial_barrier(BarrierSetT *bs, T* dst_raw, T* p) {
107 const size_t pd = pointer_delta(p, dst_raw, (size_t)heapOopSize);
108 // pointer delta is scaled to number of elements (length field in
109 // objArrayOop) which we assume is 32 bit.
110 assert(pd == (size_t)(int)pd, "length field overflow");
111 if (pd > 0) {
112 // Copied at least one element; call the barrier.
113 bs->write_ref_array((HeapWord*)dst_raw, pd);
114 }
115 }
116
117 template <DecoratorSet decorators, typename BarrierSetT>
118 template <typename T>
119 inline OopCopyResult CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
120 oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
121 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
122 size_t length) {
123 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
124
125 src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
126 dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
127
128 if ((!HasDecorator<decorators, ARRAYCOPY_CHECKCAST>::value) &&
129 (!HasDecorator<decorators, ARRAYCOPY_NOTNULL>::value)) {
130 // Optimized covariant case
131 if (!HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value) {
132 bs->write_ref_array_pre(dst_raw, length);
133 }
134 Raw::oop_arraycopy(nullptr, 0, src_raw, nullptr, 0, dst_raw, length);
135 bs->write_ref_array((HeapWord*)dst_raw, length);
136 } else {
137 assert(dst_obj != nullptr, "better have an actual oop");
138 Klass* bound = objArrayOop(dst_obj)->element_klass();
139 T* from = const_cast<T*>(src_raw);
140 T* end = from + length;
141 for (T* p = dst_raw; from < end; from++, p++) {
142 T element = *from;
143 // Apply any required checks
144 if (HasDecorator<decorators, ARRAYCOPY_NOTNULL>::value && CompressedOops::is_null(element)) {
145 oop_arraycopy_partial_barrier(bs, dst_raw, p);
146 return OopCopyResult::failed_check_null;
147 }
148 if (HasDecorator<decorators, ARRAYCOPY_CHECKCAST>::value &&
149 (!oopDesc::is_instanceof_or_null(CompressedOops::decode(element), bound))) {
150 oop_arraycopy_partial_barrier(bs, dst_raw, p);
151 return OopCopyResult::failed_check_class_cast;
152 }
153 // write
154 bs->template write_ref_field_pre<decorators>(p);
155 *p = element;
156 }
157 bs->write_ref_array((HeapWord*)dst_raw, length);
158 }
159
160 return OopCopyResult::ok;
161 }
162
163 template <DecoratorSet decorators, typename BarrierSetT>
164 inline void CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
165 clone_in_heap(oop src, oop dst, size_t size) {
166 Raw::clone(src, dst, size);
167 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
168 bs->write_region(MemRegion((HeapWord*)(void*)dst, size));
169 }
170
171 template <DecoratorSet decorators, typename BarrierSetT>
172 inline void CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
173 value_copy_in_heap(const ValuePayload& src, const ValuePayload& dst) {
174 precond(src.klass() == dst.klass());
175
176 const InlineKlass* md = src.klass();
177 if (!md->contains_oops()) {
178 // If we do not have oops in the flat array, we can just do a raw copy.
179 Raw::value_copy(src, dst);
180 } else {
181 BarrierSetT* bs = barrier_set_cast<BarrierSetT>(BarrierSet::barrier_set());
182 // addr() points at the payload start, the oop map offset are relative to
183 // the object header, adjust address to account for this discrepancy.
184 const address oop_map_adjusted_dst_addr = dst.addr() - md->payload_offset();
185 typedef typename ValueOopType<decorators>::type OopType;
186
187 // Pre-barriers...
188 if (!HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value) {
189 OopMapBlock* map = md->start_of_nonstatic_oop_maps();
190 OopMapBlock* const end = map + md->nonstatic_oop_map_count();
191
192 while (map != end) {
193 address doop_address = oop_map_adjusted_dst_addr + map->offset();
194
195 bs->write_ref_array_pre((OopType*) doop_address, map->count());
196 map++;
197 }
198 }
199
200 Raw::value_copy(src, dst);
201
202 // Post-barriers...
203 OopMapBlock* map = md->start_of_nonstatic_oop_maps();
204 OopMapBlock* const end = map + md->nonstatic_oop_map_count();
205 while (map != end) {
206 address doop_address = oop_map_adjusted_dst_addr + map->offset();
207 // The post-barrier needs to be called for initialized and uninitialized destinations.
208 bs->write_ref_array((HeapWord*) doop_address, map->count());
209 map++;
210 }
211 }
212 }
213
214 template <DecoratorSet decorators, typename BarrierSetT>
215 inline void CardTableBarrierSet::AccessBarrier<decorators, BarrierSetT>::
216 value_store_null_in_heap(const ValuePayload& dst) {
217 const InlineKlass* md = dst.klass();
218 if (!md->contains_oops()) {
219 // If we do not have oops in the flat array, we can just do a raw clear.
220 Raw::value_store_null(dst);
221 } else {
222 BarrierSetT* bs = barrier_set_cast<BarrierSetT>(BarrierSet::barrier_set());
223 // addr() points at the payload start, the oop map offset are relative to
224 // the object header, adjust address to account for this discrepancy.
225 const address oop_map_adjusted_dst_addr = dst.addr() - md->payload_offset();
226 typedef typename ValueOopType<decorators>::type OopType;
227
228 // Pre-barriers...
229 if (!HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value) {
230 OopMapBlock* map = md->start_of_nonstatic_oop_maps();
231 OopMapBlock* const end = map + md->nonstatic_oop_map_count();
232 while (map != end) {
233 address doop_address = oop_map_adjusted_dst_addr + map->offset();
234 bs->write_ref_array_pre((OopType*) doop_address, map->count());
235 map++;
236 }
237 }
238
239 Raw::value_store_null(dst);
240
241 // Storing null does not require post-barriers
242 }
243 }
244
245 #endif // SHARE_GC_SHARED_CARDTABLEBARRIERSET_INLINE_HPP