1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 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
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
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 23  */
 24 
 25 #ifndef SHARE_OOPS_ACCESSBACKEND_INLINE_HPP
 26 #define SHARE_OOPS_ACCESSBACKEND_INLINE_HPP
 27 
 28 #include "oops/accessBackend.hpp"
 29 
 30 #include "oops/access.hpp"
 31 #include "oops/arrayOop.hpp"
 32 #include "oops/compressedOops.inline.hpp"
 33 #include "oops/oopsHierarchy.hpp"
 34 #include "runtime/atomic.hpp"
 35 #include "runtime/orderAccess.hpp"
 36 #include "oops/inlineKlass.hpp"
 37 
 38 #include <type_traits>
 39 
 40 template <DecoratorSet decorators>
 41 template <DecoratorSet idecorators, typename T>
 42 inline typename EnableIf<
 43   AccessInternal::MustConvertCompressedOop<idecorators, T>::value, T>::type
 44 RawAccessBarrier<decorators>::decode_internal(typename HeapOopType<idecorators>::type value) {
 45   if (HasDecorator<decorators, IS_NOT_NULL>::value) {
 46     return CompressedOops::decode_not_null(value);
 47   } else {
 48     return CompressedOops::decode(value);
 49   }
 50 }
 51 
 52 template <DecoratorSet decorators>
 53 template <DecoratorSet idecorators, typename T>
 54 inline typename EnableIf<
 55   AccessInternal::MustConvertCompressedOop<idecorators, T>::value,
 56   typename HeapOopType<idecorators>::type>::type
 57 RawAccessBarrier<decorators>::encode_internal(T value) {
 58   if (HasDecorator<decorators, IS_NOT_NULL>::value) {
 59     return CompressedOops::encode_not_null(value);
 60   } else {
 61     return CompressedOops::encode(value);
 62   }
 63 }
 64 
 65 template <DecoratorSet decorators>
 66 template <typename T>
 67 inline void RawAccessBarrier<decorators>::oop_store(void* addr, T value) {
 68   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
 69   Encoded encoded = encode(value);
 70   store(reinterpret_cast<Encoded*>(addr), encoded);
 71 }
 72 
 73 template <DecoratorSet decorators>
 74 template <typename T>
 75 inline void RawAccessBarrier<decorators>::oop_store_at(oop base, ptrdiff_t offset, T value) {
 76   oop_store(field_addr(base, offset), value);
 77 }
 78 
 79 template <DecoratorSet decorators>
 80 template <typename T>
 81 inline T RawAccessBarrier<decorators>::oop_load(void* addr) {
 82   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
 83   Encoded encoded = load<Encoded>(reinterpret_cast<Encoded*>(addr));
 84   return decode<T>(encoded);
 85 }
 86 
 87 template <DecoratorSet decorators>
 88 template <typename T>
 89 inline T RawAccessBarrier<decorators>::oop_load_at(oop base, ptrdiff_t offset) {
 90   return oop_load<T>(field_addr(base, offset));
 91 }
 92 
 93 template <DecoratorSet decorators>
 94 template <typename T>
 95 inline T RawAccessBarrier<decorators>::oop_atomic_cmpxchg(void* addr, T compare_value, T new_value) {
 96   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
 97   Encoded encoded_new = encode(new_value);
 98   Encoded encoded_compare = encode(compare_value);
 99   Encoded encoded_result = atomic_cmpxchg(reinterpret_cast<Encoded*>(addr),
100                                           encoded_compare,
101                                           encoded_new);
102   return decode<T>(encoded_result);
103 }
104 
105 template <DecoratorSet decorators>
106 template <typename T>
107 inline T RawAccessBarrier<decorators>::oop_atomic_cmpxchg_at(oop base, ptrdiff_t offset, T compare_value, T new_value) {
108   return oop_atomic_cmpxchg(field_addr(base, offset), compare_value, new_value);
109 }
110 
111 template <DecoratorSet decorators>
112 template <typename T>
113 inline T RawAccessBarrier<decorators>::oop_atomic_xchg(void* addr, T new_value) {
114   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
115   Encoded encoded_new = encode(new_value);
116   Encoded encoded_result = atomic_xchg(reinterpret_cast<Encoded*>(addr), encoded_new);
117   return decode<T>(encoded_result);
118 }
119 
120 template <DecoratorSet decorators>
121 template <typename T>
122 inline T RawAccessBarrier<decorators>::oop_atomic_xchg_at(oop base, ptrdiff_t offset, T new_value) {
123   return oop_atomic_xchg(field_addr(base, offset), new_value);
124 }
125 
126 template <DecoratorSet decorators>
127 template <typename T>
128 inline void RawAccessBarrier<decorators>::oop_arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
129                                                         arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
130                                                         size_t length) {
131   arraycopy(src_obj, src_offset_in_bytes, src_raw,
132             dst_obj, dst_offset_in_bytes, dst_raw,
133             length);
134 }
135 
136 template <DecoratorSet decorators>
137 template <DecoratorSet ds, typename T>
138 inline typename EnableIf<
139   HasDecorator<ds, MO_SEQ_CST>::value, T>::type
140 RawAccessBarrier<decorators>::load_internal(void* addr) {
141   if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
142     OrderAccess::fence();
143   }
144   return Atomic::load_acquire(reinterpret_cast<const volatile T*>(addr));
145 }
146 
147 template <DecoratorSet decorators>
148 template <DecoratorSet ds, typename T>
149 inline typename EnableIf<
150   HasDecorator<ds, MO_ACQUIRE>::value, T>::type
151 RawAccessBarrier<decorators>::load_internal(void* addr) {
152   return Atomic::load_acquire(reinterpret_cast<const volatile T*>(addr));
153 }
154 
155 template <DecoratorSet decorators>
156 template <DecoratorSet ds, typename T>
157 inline typename EnableIf<
158   HasDecorator<ds, MO_RELAXED>::value, T>::type
159 RawAccessBarrier<decorators>::load_internal(void* addr) {
160   return Atomic::load(reinterpret_cast<const volatile T*>(addr));
161 }
162 
163 template <DecoratorSet decorators>
164 template <DecoratorSet ds, typename T>
165 inline typename EnableIf<
166   HasDecorator<ds, MO_SEQ_CST>::value>::type
167 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
168   Atomic::release_store_fence(reinterpret_cast<volatile T*>(addr), value);
169 }
170 
171 template <DecoratorSet decorators>
172 template <DecoratorSet ds, typename T>
173 inline typename EnableIf<
174   HasDecorator<ds, MO_RELEASE>::value>::type
175 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
176   Atomic::release_store(reinterpret_cast<volatile T*>(addr), value);
177 }
178 
179 template <DecoratorSet decorators>
180 template <DecoratorSet ds, typename T>
181 inline typename EnableIf<
182   HasDecorator<ds, MO_RELAXED>::value>::type
183 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
184   Atomic::store(reinterpret_cast<volatile T*>(addr), value);
185 }
186 
187 template <DecoratorSet decorators>
188 template <DecoratorSet ds, typename T>
189 inline typename EnableIf<
190   HasDecorator<ds, MO_RELAXED>::value, T>::type
191 RawAccessBarrier<decorators>::atomic_cmpxchg_internal(void* addr, T compare_value, T new_value) {
192   return Atomic::cmpxchg(reinterpret_cast<volatile T*>(addr),
193                          compare_value,
194                          new_value,
195                          memory_order_relaxed);
196 }
197 
198 template <DecoratorSet decorators>
199 template <DecoratorSet ds, typename T>
200 inline typename EnableIf<
201   HasDecorator<ds, MO_SEQ_CST>::value, T>::type
202 RawAccessBarrier<decorators>::atomic_cmpxchg_internal(void* addr, T compare_value, T new_value) {
203   return Atomic::cmpxchg(reinterpret_cast<volatile T*>(addr),
204                          compare_value,
205                          new_value,
206                          memory_order_conservative);
207 }
208 
209 template <DecoratorSet decorators>
210 template <DecoratorSet ds, typename T>
211 inline typename EnableIf<
212   HasDecorator<ds, MO_SEQ_CST>::value, T>::type
213 RawAccessBarrier<decorators>::atomic_xchg_internal(void* addr, T new_value) {
214   return Atomic::xchg(reinterpret_cast<volatile T*>(addr),
215                       new_value);
216 }
217 
218 class RawAccessBarrierArrayCopy: public AllStatic {
219   template<typename T> struct IsHeapWordSized: public std::integral_constant<bool, sizeof(T) == HeapWordSize> { };
220 public:
221   template <DecoratorSet decorators, typename T>
222   static inline typename EnableIf<
223     HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value>::type
224   arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
225             arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
226             size_t length) {
227     src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
228     dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
229 
230     // We do not check for ARRAYCOPY_ATOMIC for oops, because they are unconditionally always atomic.
231     if (HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value) {
232       AccessInternal::arraycopy_arrayof_conjoint_oops(src_raw, dst_raw, length);
233     } else {
234       typedef typename HeapOopType<decorators>::type OopType;
235       AccessInternal::arraycopy_conjoint_oops(reinterpret_cast<OopType*>(src_raw),
236                                               reinterpret_cast<OopType*>(dst_raw), length);
237     }
238   }
239 
240   template <DecoratorSet decorators, typename T>
241   static inline typename EnableIf<
242     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value &&
243     HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value>::type
244   arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
245             arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
246             size_t length) {
247     src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
248     dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
249 
250     AccessInternal::arraycopy_arrayof_conjoint(src_raw, dst_raw, length);
251   }
252 
253   template <DecoratorSet decorators, typename T>
254   static inline typename EnableIf<
255     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value &&
256     HasDecorator<decorators, ARRAYCOPY_DISJOINT>::value && IsHeapWordSized<T>::value>::type
257   arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
258             arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
259             size_t length) {
260     src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
261     dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
262 
263     // There is only a disjoint optimization for word granularity copying
264     if (HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value) {
265       AccessInternal::arraycopy_disjoint_words_atomic(src_raw, dst_raw, length);
266     } else {
267       AccessInternal::arraycopy_disjoint_words(src_raw, dst_raw, length);
268     }
269   }
270 
271   template <DecoratorSet decorators, typename T>
272   static inline typename EnableIf<
273     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value &&
274     !(HasDecorator<decorators, ARRAYCOPY_DISJOINT>::value && IsHeapWordSized<T>::value) &&
275     !HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value &&
276     !HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value>::type
277   arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
278             arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
279             size_t length) {
280     src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
281     dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
282 
283     AccessInternal::arraycopy_conjoint(src_raw, dst_raw, length);
284   }
285 
286   template <DecoratorSet decorators, typename T>
287   static inline typename EnableIf<
288     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value &&
289     !(HasDecorator<decorators, ARRAYCOPY_DISJOINT>::value && IsHeapWordSized<T>::value) &&
290     !HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value &&
291     HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value>::type
292   arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
293             arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
294             size_t length) {
295     src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
296     dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
297 
298     AccessInternal::arraycopy_conjoint_atomic(src_raw, dst_raw, length);
299   }
300 };
301 
302 template<> struct RawAccessBarrierArrayCopy::IsHeapWordSized<void>: public std::false_type { };
303 
304 template <DecoratorSet decorators>
305 template <typename T>
306 inline void RawAccessBarrier<decorators>::arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
307                                                     arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
308                                                     size_t length) {
309   RawAccessBarrierArrayCopy::arraycopy<decorators>(src_obj, src_offset_in_bytes, src_raw,
310                                                    dst_obj, dst_offset_in_bytes, dst_raw,
311                                                    length);
312 }
313 
314 template <DecoratorSet decorators>
315 inline void RawAccessBarrier<decorators>::clone(oop src, oop dst, size_t size) {
316   // 4839641 (4840070): We must do an oop-atomic copy, because if another thread
317   // is modifying a reference field in the clonee, a non-oop-atomic copy might
318   // be suspended in the middle of copying the pointer and end up with parts
319   // of two different pointers in the field.  Subsequent dereferences will crash.
320   // 4846409: an oop-copy of objects with long or double fields or arrays of same
321   // won't copy the longs/doubles atomically in 32-bit vm's, so we copy jlongs instead
322   // of oops.  We know objects are aligned on a minimum of an jlong boundary.
323   // The same is true of StubRoutines::object_copy and the various oop_copy
324   // variants, and of the code generated by the inline_native_clone intrinsic.
325 
326   assert(MinObjAlignmentInBytes >= BytesPerLong, "objects misaligned");
327   AccessInternal::arraycopy_conjoint_atomic(reinterpret_cast<jlong*>((oopDesc*)src),
328                                             reinterpret_cast<jlong*>((oopDesc*)dst),
329                                             align_object_size(size) / HeapWordsPerLong);
330   // Clear the header
331   dst->init_mark();
332 }
333 
334 template <DecoratorSet decorators>
335 inline void RawAccessBarrier<decorators>::value_copy(void* src, void* dst, InlineKlass* md) {
336   assert(is_aligned(src, md->get_alignment()) && is_aligned(dst, md->get_alignment()), "Unalign value_copy");
337   AccessInternal::arraycopy_conjoint_atomic(src, dst, static_cast<size_t>(md->get_payload_size_in_bytes()));
338 }
339 #endif // SHARE_OOPS_ACCESSBACKEND_INLINE_HPP