rev 49674 : 8198285: More consistent Access API for arraycopy

   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
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  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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  24 
  25 #ifndef SHARE_VM_RUNTIME_ACCESSBACKEND_INLINE_HPP
  26 #define SHARE_VM_RUNTIME_ACCESSBACKEND_INLINE_HPP
  27 
  28 #include "oops/access.hpp"
  29 #include "oops/accessBackend.hpp"
  30 #include "oops/compressedOops.inline.hpp"
  31 #include "oops/oopsHierarchy.hpp"
  32 
  33 template <DecoratorSet decorators>
  34 template <DecoratorSet idecorators, typename T>
  35 inline typename EnableIf<
  36   AccessInternal::MustConvertCompressedOop<idecorators, T>::value, T>::type
  37 RawAccessBarrier<decorators>::decode_internal(typename HeapOopType<idecorators>::type value) {
  38   if (HasDecorator<decorators, OOP_NOT_NULL>::value) {
  39     return CompressedOops::decode_not_null(value);
  40   } else {
  41     return CompressedOops::decode(value);
  42   }
  43 }
  44 
  45 template <DecoratorSet decorators>
  46 template <DecoratorSet idecorators, typename T>
  47 inline typename EnableIf<
  48   AccessInternal::MustConvertCompressedOop<idecorators, T>::value,
  49   typename HeapOopType<idecorators>::type>::type
  50 RawAccessBarrier<decorators>::encode_internal(T value) {
  51   if (HasDecorator<decorators, OOP_NOT_NULL>::value) {
  52     return CompressedOops::encode_not_null(value);
  53   } else {
  54     return CompressedOops::encode(value);
  55   }
  56 }
  57 
  58 template <DecoratorSet decorators>
  59 template <typename T>
  60 inline void RawAccessBarrier<decorators>::oop_store(void* addr, T value) {
  61   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
  62   Encoded encoded = encode(value);
  63   store(reinterpret_cast<Encoded*>(addr), encoded);
  64 }
  65 
  66 template <DecoratorSet decorators>
  67 template <typename T>
  68 inline void RawAccessBarrier<decorators>::oop_store_at(oop base, ptrdiff_t offset, T value) {
  69   oop_store(field_addr(base, offset), value);
  70 }
  71 
  72 template <DecoratorSet decorators>
  73 template <typename T>
  74 inline T RawAccessBarrier<decorators>::oop_load(void* addr) {
  75   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
  76   Encoded encoded = load<Encoded>(reinterpret_cast<Encoded*>(addr));
  77   return decode<T>(encoded);
  78 }
  79 
  80 template <DecoratorSet decorators>
  81 template <typename T>
  82 inline T RawAccessBarrier<decorators>::oop_load_at(oop base, ptrdiff_t offset) {
  83   return oop_load<T>(field_addr(base, offset));
  84 }
  85 
  86 template <DecoratorSet decorators>
  87 template <typename T>
  88 inline T RawAccessBarrier<decorators>::oop_atomic_cmpxchg(T new_value, void* addr, T compare_value) {
  89   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
  90   Encoded encoded_new = encode(new_value);
  91   Encoded encoded_compare = encode(compare_value);
  92   Encoded encoded_result = atomic_cmpxchg(encoded_new,
  93                                           reinterpret_cast<Encoded*>(addr),
  94                                           encoded_compare);
  95   return decode<T>(encoded_result);
  96 }
  97 
  98 template <DecoratorSet decorators>
  99 template <typename T>
 100 inline T RawAccessBarrier<decorators>::oop_atomic_cmpxchg_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {
 101   return oop_atomic_cmpxchg(new_value, field_addr(base, offset), compare_value);
 102 }
 103 
 104 template <DecoratorSet decorators>
 105 template <typename T>
 106 inline T RawAccessBarrier<decorators>::oop_atomic_xchg(T new_value, void* addr) {
 107   typedef typename AccessInternal::EncodedType<decorators, T>::type Encoded;
 108   Encoded encoded_new = encode(new_value);
 109   Encoded encoded_result = atomic_xchg(encoded_new, reinterpret_cast<Encoded*>(addr));
 110   return decode<T>(encoded_result);
 111 }
 112 
 113 template <DecoratorSet decorators>
 114 template <typename T>
 115 inline T RawAccessBarrier<decorators>::oop_atomic_xchg_at(T new_value, oop base, ptrdiff_t offset) {
 116   return oop_atomic_xchg(new_value, field_addr(base, offset));
 117 }
 118 
 119 template <DecoratorSet decorators>
 120 template <typename T>
 121 inline bool RawAccessBarrier<decorators>::oop_arraycopy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {
 122   return arraycopy(src_obj, dst_obj, src, dst, length);
 123 }
 124 
 125 template <DecoratorSet decorators>
 126 template <DecoratorSet ds, typename T>
 127 inline typename EnableIf<
 128   HasDecorator<ds, MO_SEQ_CST>::value, T>::type
 129 RawAccessBarrier<decorators>::load_internal(void* addr) {
 130   if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
 131     OrderAccess::fence();
 132   }
 133   return OrderAccess::load_acquire(reinterpret_cast<const volatile T*>(addr));
 134 }
 135 
 136 template <DecoratorSet decorators>
 137 template <DecoratorSet ds, typename T>
 138 inline typename EnableIf<
 139   HasDecorator<ds, MO_ACQUIRE>::value, T>::type
 140 RawAccessBarrier<decorators>::load_internal(void* addr) {
 141   return OrderAccess::load_acquire(reinterpret_cast<const volatile T*>(addr));
 142 }
 143 
 144 template <DecoratorSet decorators>
 145 template <DecoratorSet ds, typename T>
 146 inline typename EnableIf<
 147   HasDecorator<ds, MO_RELAXED>::value, T>::type
 148 RawAccessBarrier<decorators>::load_internal(void* addr) {
 149   return Atomic::load(reinterpret_cast<const volatile T*>(addr));
 150 }
 151 
 152 template <DecoratorSet decorators>
 153 template <DecoratorSet ds, typename T>
 154 inline typename EnableIf<
 155   HasDecorator<ds, MO_SEQ_CST>::value>::type
 156 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
 157   OrderAccess::release_store_fence(reinterpret_cast<volatile T*>(addr), value);
 158 }
 159 
 160 template <DecoratorSet decorators>
 161 template <DecoratorSet ds, typename T>
 162 inline typename EnableIf<
 163   HasDecorator<ds, MO_RELEASE>::value>::type
 164 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
 165   OrderAccess::release_store(reinterpret_cast<volatile T*>(addr), value);
 166 }
 167 
 168 template <DecoratorSet decorators>
 169 template <DecoratorSet ds, typename T>
 170 inline typename EnableIf<
 171   HasDecorator<ds, MO_RELAXED>::value>::type
 172 RawAccessBarrier<decorators>::store_internal(void* addr, T value) {
 173   Atomic::store(value, reinterpret_cast<volatile T*>(addr));
 174 }
 175 
 176 template <DecoratorSet decorators>
 177 template <DecoratorSet ds, typename T>
 178 inline typename EnableIf<
 179   HasDecorator<ds, MO_RELAXED>::value, T>::type
 180 RawAccessBarrier<decorators>::atomic_cmpxchg_internal(T new_value, void* addr, T compare_value) {
 181   return Atomic::cmpxchg(new_value,
 182                          reinterpret_cast<volatile T*>(addr),
 183                          compare_value,
 184                          memory_order_relaxed);
 185 }
 186 
 187 template <DecoratorSet decorators>
 188 template <DecoratorSet ds, typename T>
 189 inline typename EnableIf<
 190   HasDecorator<ds, MO_SEQ_CST>::value, T>::type
 191 RawAccessBarrier<decorators>::atomic_cmpxchg_internal(T new_value, void* addr, T compare_value) {
 192   return Atomic::cmpxchg(new_value,
 193                          reinterpret_cast<volatile T*>(addr),
 194                          compare_value,
 195                          memory_order_conservative);
 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_xchg_internal(T new_value, void* addr) {
 203   return Atomic::xchg(new_value,
 204                       reinterpret_cast<volatile T*>(addr));
 205 }
 206 
 207 // For platforms that do not have native support for wide atomics,
 208 // we can emulate the atomicity using a lock. So here we check
 209 // whether that is necessary or not.
 210 
 211 template <DecoratorSet ds>
 212 template <DecoratorSet decorators, typename T>
 213 inline typename EnableIf<
 214   AccessInternal::PossiblyLockedAccess<T>::value, T>::type
 215 RawAccessBarrier<ds>::atomic_xchg_maybe_locked(T new_value, void* addr) {
 216   if (!AccessInternal::wide_atomic_needs_locking()) {
 217     return atomic_xchg_internal<ds>(new_value, addr);
 218   } else {
 219     AccessInternal::AccessLocker access_lock;
 220     volatile T* p = reinterpret_cast<volatile T*>(addr);
 221     T old_val = RawAccess<>::load(p);
 222     RawAccess<>::store(p, new_value);
 223     return old_val;
 224   }
 225 }
 226 
 227 template <DecoratorSet ds>
 228 template <DecoratorSet decorators, typename T>
 229 inline typename EnableIf<
 230   AccessInternal::PossiblyLockedAccess<T>::value, T>::type
 231 RawAccessBarrier<ds>::atomic_cmpxchg_maybe_locked(T new_value, void* addr, T compare_value) {
 232   if (!AccessInternal::wide_atomic_needs_locking()) {
 233     return atomic_cmpxchg_internal<ds>(new_value, addr, compare_value);
 234   } else {
 235     AccessInternal::AccessLocker access_lock;
 236     volatile T* p = reinterpret_cast<volatile T*>(addr);
 237     T old_val = RawAccess<>::load(p);
 238     if (old_val == compare_value) {
 239       RawAccess<>::store(p, new_value);
 240     }
 241     return old_val;
 242   }
 243 }
 244 
 245 class RawAccessBarrierArrayCopy: public AllStatic {
 246 public:
 247   template <DecoratorSet decorators, typename T>
 248   static inline typename EnableIf<
 249   HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value>::type
 250   arraycopy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {




 251     // We do not check for ARRAYCOPY_ATOMIC for oops, because they are unconditionally always atomic.
 252     if (HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value) {
 253       AccessInternal::arraycopy_arrayof_conjoint_oops(src, dst, length);
 254     } else {
 255       typedef typename HeapOopType<decorators>::type OopType;
 256       AccessInternal::arraycopy_conjoint_oops(reinterpret_cast<OopType*>(src),
 257                                               reinterpret_cast<OopType*>(dst), length);
 258     }
 259   }
 260 
 261   template <DecoratorSet decorators, typename T>
 262   static inline typename EnableIf<
 263     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value>::type
 264   arraycopy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {




 265     if (HasDecorator<decorators, ARRAYCOPY_ARRAYOF>::value) {
 266       AccessInternal::arraycopy_arrayof_conjoint(src, dst, length);
 267     } else if (HasDecorator<decorators, ARRAYCOPY_DISJOINT>::value && sizeof(T) == HeapWordSize) {
 268       // There is only a disjoint optimization for word granularity copying
 269       if (HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value) {
 270         AccessInternal::arraycopy_disjoint_words_atomic(src, dst, length);
 271       } else {
 272         AccessInternal::arraycopy_disjoint_words(src, dst, length);
 273       }
 274     } else {
 275       if (HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value) {
 276         AccessInternal::arraycopy_conjoint_atomic(src, dst, length);
 277       } else {
 278         AccessInternal::arraycopy_conjoint(src, dst, length);
 279       }
 280     }
 281   }
 282 
 283   template <DecoratorSet decorators>
 284   static inline typename EnableIf<
 285     !HasDecorator<decorators, INTERNAL_VALUE_IS_OOP>::value>::type
 286   arraycopy(arrayOop src_obj, arrayOop dst_obj, void* src, void* dst, size_t length) {




 287     if (HasDecorator<decorators, ARRAYCOPY_ATOMIC>::value) {
 288       AccessInternal::arraycopy_conjoint_atomic(src, dst, length);
 289     } else {
 290       AccessInternal::arraycopy_conjoint(src, dst, length);
 291     }
 292   }
 293 };
 294 
 295 template <DecoratorSet decorators>
 296 template <typename T>
 297 inline bool RawAccessBarrier<decorators>::arraycopy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {
 298   RawAccessBarrierArrayCopy::arraycopy<decorators>(src_obj, dst_obj, src, dst, length);
 299   return true;
 300 }
 301 
 302 template <DecoratorSet decorators>
 303 inline void RawAccessBarrier<decorators>::clone(oop src, oop dst, size_t size) {
 304   // 4839641 (4840070): We must do an oop-atomic copy, because if another thread
 305   // is modifying a reference field in the clonee, a non-oop-atomic copy might
 306   // be suspended in the middle of copying the pointer and end up with parts
 307   // of two different pointers in the field.  Subsequent dereferences will crash.
 308   // 4846409: an oop-copy of objects with long or double fields or arrays of same
 309   // won't copy the longs/doubles atomically in 32-bit vm's, so we copy jlongs instead
 310   // of oops.  We know objects are aligned on a minimum of an jlong boundary.
 311   // The same is true of StubRoutines::object_copy and the various oop_copy
 312   // variants, and of the code generated by the inline_native_clone intrinsic.
 313 
 314   assert(MinObjAlignmentInBytes >= BytesPerLong, "objects misaligned");
 315   AccessInternal::arraycopy_conjoint_atomic(reinterpret_cast<jlong*>((oopDesc*)src),
 316                                             reinterpret_cast<jlong*>((oopDesc*)dst),
 317                                             align_object_size(size) / HeapWordsPerLong);
 318   // Clear the header
 319   dst->init_mark_raw();
 320 }
 321 
 322 #endif // SHARE_VM_RUNTIME_ACCESSBACKEND_INLINE_HPP
--- EOF ---