1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
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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).
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  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_OOPS_ACCESS_INLINE_HPP
  26 #define SHARE_OOPS_ACCESS_INLINE_HPP
  27 
  28 #include "gc/shared/barrierSet.inline.hpp"
  29 #include "gc/shared/barrierSetConfig.inline.hpp"
  30 #include "oops/access.hpp"
  31 #include "oops/accessBackend.inline.hpp"
  32 
  33 // This file outlines the last 2 steps of the template pipeline of accesses going through
  34 // the Access API.
  35 // * Step 5.a: Barrier resolution. This step is invoked the first time a runtime-dispatch
  36 //             happens for an access. The appropriate BarrierSet::AccessBarrier accessor
  37 //             is resolved, then the function pointer is updated to that accessor for
  38 //             future invocations.
  39 // * Step 5.b: Post-runtime dispatch. This step now casts previously unknown types such
  40 //             as the address type of an oop on the heap (is it oop* or narrowOop*) to
  41 //             the appropriate type. It also splits sufficiently orthogonal accesses into
  42 //             different functions, such as whether the access involves oops or primitives
  43 //             and whether the access is performed on the heap or outside. Then the
  44 //             appropriate BarrierSet::AccessBarrier is called to perform the access.
  45 
  46 namespace AccessInternal {
  47   // Step 5.b: Post-runtime dispatch.
  48   // This class is the last step before calling the BarrierSet::AccessBarrier.
  49   // Here we make sure to figure out types that were not known prior to the
  50   // runtime dispatch, such as whether an oop on the heap is oop or narrowOop.
  51   // We also split orthogonal barriers such as handling primitives vs oops
  52   // and on-heap vs off-heap into different calls to the barrier set.
  53   template <class GCBarrierType, BarrierType type, DecoratorSet decorators>
  54   struct PostRuntimeDispatch: public AllStatic { };
  55 
  56   template <class GCBarrierType, DecoratorSet decorators>
  57   struct PostRuntimeDispatch<GCBarrierType, BARRIER_STORE, decorators>: public AllStatic {
  58     template <typename T>
  59     static void access_barrier(void* addr, T value) {
  60       GCBarrierType::store_in_heap(reinterpret_cast<T*>(addr), value);
  61     }
  62 
  63     static void oop_access_barrier(void* addr, oop value) {
  64       typedef typename HeapOopType<decorators>::type OopType;
  65       if (HasDecorator<decorators, IN_HEAP>::value) {
  66         GCBarrierType::oop_store_in_heap(reinterpret_cast<OopType*>(addr), value);
  67       } else {
  68         GCBarrierType::oop_store_not_in_heap(reinterpret_cast<OopType*>(addr), value);
  69       }
  70     }
  71   };
  72 
  73   template <class GCBarrierType, DecoratorSet decorators>
  74   struct PostRuntimeDispatch<GCBarrierType, BARRIER_LOAD, decorators>: public AllStatic {
  75     template <typename T>
  76     static T access_barrier(void* addr) {
  77       return GCBarrierType::load_in_heap(reinterpret_cast<T*>(addr));
  78     }
  79 
  80     static oop oop_access_barrier(void* addr) {
  81       typedef typename HeapOopType<decorators>::type OopType;
  82       if (HasDecorator<decorators, IN_HEAP>::value) {
  83         return GCBarrierType::oop_load_in_heap(reinterpret_cast<OopType*>(addr));
  84       } else {
  85         return GCBarrierType::oop_load_not_in_heap(reinterpret_cast<OopType*>(addr));
  86       }
  87     }
  88   };
  89 
  90   template <class GCBarrierType, DecoratorSet decorators>
  91   struct PostRuntimeDispatch<GCBarrierType, BARRIER_ATOMIC_XCHG, decorators>: public AllStatic {
  92     template <typename T>
  93     static T access_barrier(T new_value, void* addr) {
  94       return GCBarrierType::atomic_xchg_in_heap(new_value, reinterpret_cast<T*>(addr));
  95     }
  96 
  97     static oop oop_access_barrier(oop new_value, void* addr) {
  98       typedef typename HeapOopType<decorators>::type OopType;
  99       if (HasDecorator<decorators, IN_HEAP>::value) {
 100         return GCBarrierType::oop_atomic_xchg_in_heap(new_value, reinterpret_cast<OopType*>(addr));
 101       } else {
 102         return GCBarrierType::oop_atomic_xchg_not_in_heap(new_value, reinterpret_cast<OopType*>(addr));
 103       }
 104     }
 105   };
 106 
 107   template <class GCBarrierType, DecoratorSet decorators>
 108   struct PostRuntimeDispatch<GCBarrierType, BARRIER_ATOMIC_CMPXCHG, decorators>: public AllStatic {
 109     template <typename T>
 110     static T access_barrier(T new_value, void* addr, T compare_value) {
 111       return GCBarrierType::atomic_cmpxchg_in_heap(new_value, reinterpret_cast<T*>(addr), compare_value);
 112     }
 113 
 114     static oop oop_access_barrier(oop new_value, void* addr, oop compare_value) {
 115       typedef typename HeapOopType<decorators>::type OopType;
 116       if (HasDecorator<decorators, IN_HEAP>::value) {
 117         return GCBarrierType::oop_atomic_cmpxchg_in_heap(new_value, reinterpret_cast<OopType*>(addr), compare_value);
 118       } else {
 119         return GCBarrierType::oop_atomic_cmpxchg_not_in_heap(new_value, reinterpret_cast<OopType*>(addr), compare_value);
 120       }
 121     }
 122   };
 123 
 124   template <class GCBarrierType, DecoratorSet decorators>
 125   struct PostRuntimeDispatch<GCBarrierType, BARRIER_ARRAYCOPY, decorators>: public AllStatic {
 126     template <typename T>
 127     static bool access_barrier(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
 128                                arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
 129                                size_t length) {
 130       GCBarrierType::arraycopy_in_heap(src_obj, src_offset_in_bytes, src_raw,
 131                                        dst_obj, dst_offset_in_bytes, dst_raw,
 132                                        length);
 133       return true;
 134     }
 135 
 136     template <typename T>
 137     static bool oop_access_barrier(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
 138                                    arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
 139                                    size_t length) {
 140       typedef typename HeapOopType<decorators>::type OopType;
 141       return GCBarrierType::oop_arraycopy_in_heap(src_obj, src_offset_in_bytes, reinterpret_cast<OopType*>(src_raw),
 142                                                   dst_obj, dst_offset_in_bytes, reinterpret_cast<OopType*>(dst_raw),
 143                                                   length);
 144     }
 145   };
 146 
 147   template <class GCBarrierType, DecoratorSet decorators>
 148   struct PostRuntimeDispatch<GCBarrierType, BARRIER_STORE_AT, decorators>: public AllStatic {
 149     template <typename T>
 150     static void access_barrier(oop base, ptrdiff_t offset, T value) {
 151       GCBarrierType::store_in_heap_at(base, offset, value);
 152     }
 153 
 154     static void oop_access_barrier(oop base, ptrdiff_t offset, oop value) {
 155       GCBarrierType::oop_store_in_heap_at(base, offset, value);
 156     }
 157   };
 158 
 159   template <class GCBarrierType, DecoratorSet decorators>
 160   struct PostRuntimeDispatch<GCBarrierType, BARRIER_LOAD_AT, decorators>: public AllStatic {
 161     template <typename T>
 162     static T access_barrier(oop base, ptrdiff_t offset) {
 163       return GCBarrierType::template load_in_heap_at<T>(base, offset);
 164     }
 165 
 166     static oop oop_access_barrier(oop base, ptrdiff_t offset) {
 167       return GCBarrierType::oop_load_in_heap_at(base, offset);
 168     }
 169   };
 170 
 171   template <class GCBarrierType, DecoratorSet decorators>
 172   struct PostRuntimeDispatch<GCBarrierType, BARRIER_ATOMIC_XCHG_AT, decorators>: public AllStatic {
 173     template <typename T>
 174     static T access_barrier(T new_value, oop base, ptrdiff_t offset) {
 175       return GCBarrierType::atomic_xchg_in_heap_at(new_value, base, offset);
 176     }
 177 
 178     static oop oop_access_barrier(oop new_value, oop base, ptrdiff_t offset) {
 179       return GCBarrierType::oop_atomic_xchg_in_heap_at(new_value, base, offset);
 180     }
 181   };
 182 
 183   template <class GCBarrierType, DecoratorSet decorators>
 184   struct PostRuntimeDispatch<GCBarrierType, BARRIER_ATOMIC_CMPXCHG_AT, decorators>: public AllStatic {
 185     template <typename T>
 186     static T access_barrier(T new_value, oop base, ptrdiff_t offset, T compare_value) {
 187       return GCBarrierType::atomic_cmpxchg_in_heap_at(new_value, base, offset, compare_value);
 188     }
 189 
 190     static oop oop_access_barrier(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
 191       return GCBarrierType::oop_atomic_cmpxchg_in_heap_at(new_value, base, offset, compare_value);
 192     }
 193   };
 194 
 195   template <class GCBarrierType, DecoratorSet decorators>
 196   struct PostRuntimeDispatch<GCBarrierType, BARRIER_CLONE, decorators>: public AllStatic {
 197     static void access_barrier(oop src, oop dst, size_t size) {
 198       GCBarrierType::clone_in_heap(src, dst, size);
 199     }
 200   };
 201 
 202   template <class GCBarrierType, DecoratorSet decorators>
 203   struct PostRuntimeDispatch<GCBarrierType, BARRIER_RESOLVE, decorators>: public AllStatic {
 204     static oop access_barrier(oop obj) {
 205       return GCBarrierType::resolve(obj);
 206     }
 207   };
 208 
 209   template <class GCBarrierType, DecoratorSet decorators>
 210   struct PostRuntimeDispatch<GCBarrierType, BARRIER_EQUALS, decorators>: public AllStatic {
 211     static bool access_barrier(oop o1, oop o2) {
 212       return GCBarrierType::equals(o1, o2);
 213     }
 214   };
 215 
 216   // Resolving accessors with barriers from the barrier set happens in two steps.
 217   // 1. Expand paths with runtime-decorators, e.g. is UseCompressedOops on or off.
 218   // 2. Expand paths for each BarrierSet available in the system.
 219   template <DecoratorSet decorators, typename FunctionPointerT, BarrierType barrier_type>
 220   struct BarrierResolver: public AllStatic {
 221     template <DecoratorSet ds>
 222     static typename EnableIf<
 223       HasDecorator<ds, INTERNAL_VALUE_IS_OOP>::value,
 224       FunctionPointerT>::type
 225     resolve_barrier_gc() {
 226       BarrierSet* bs = BarrierSet::barrier_set();
 227       assert(bs != NULL, "GC barriers invoked before BarrierSet is set");
 228       switch (bs->kind()) {
 229 #define BARRIER_SET_RESOLVE_BARRIER_CLOSURE(bs_name)                    \
 230         case BarrierSet::bs_name: {                                     \
 231           return PostRuntimeDispatch<typename BarrierSet::GetType<BarrierSet::bs_name>::type:: \
 232             AccessBarrier<ds>, barrier_type, ds>::oop_access_barrier; \
 233         }                                                               \
 234         break;
 235         FOR_EACH_CONCRETE_BARRIER_SET_DO(BARRIER_SET_RESOLVE_BARRIER_CLOSURE)
 236 #undef BARRIER_SET_RESOLVE_BARRIER_CLOSURE
 237 
 238       default:
 239         fatal("BarrierSet AccessBarrier resolving not implemented");
 240         return NULL;
 241       };
 242     }
 243 
 244     template <DecoratorSet ds>
 245     static typename EnableIf<
 246       !HasDecorator<ds, INTERNAL_VALUE_IS_OOP>::value,
 247       FunctionPointerT>::type
 248     resolve_barrier_gc() {
 249       BarrierSet* bs = BarrierSet::barrier_set();
 250       assert(bs != NULL, "GC barriers invoked before BarrierSet is set");
 251       switch (bs->kind()) {
 252 #define BARRIER_SET_RESOLVE_BARRIER_CLOSURE(bs_name)                    \
 253         case BarrierSet::bs_name: {                                       \
 254           return PostRuntimeDispatch<typename BarrierSet::GetType<BarrierSet::bs_name>::type:: \
 255             AccessBarrier<ds>, barrier_type, ds>::access_barrier; \
 256         }                                                                 \
 257         break;
 258         FOR_EACH_CONCRETE_BARRIER_SET_DO(BARRIER_SET_RESOLVE_BARRIER_CLOSURE)
 259 #undef BARRIER_SET_RESOLVE_BARRIER_CLOSURE
 260 
 261       default:
 262         fatal("BarrierSet AccessBarrier resolving not implemented");
 263         return NULL;
 264       };
 265     }
 266 
 267     static FunctionPointerT resolve_barrier_rt() {
 268       if (UseCompressedOops) {
 269         const DecoratorSet expanded_decorators = decorators | INTERNAL_RT_USE_COMPRESSED_OOPS;
 270         return resolve_barrier_gc<expanded_decorators>();
 271       } else {
 272         return resolve_barrier_gc<decorators>();
 273       }
 274     }
 275 
 276     static FunctionPointerT resolve_barrier() {
 277       return resolve_barrier_rt();
 278     }
 279   };
 280 
 281   // Step 5.a: Barrier resolution
 282   // The RuntimeDispatch class is responsible for performing a runtime dispatch of the
 283   // accessor. This is required when the access either depends on whether compressed oops
 284   // is being used, or it depends on which GC implementation was chosen (e.g. requires GC
 285   // barriers). The way it works is that a function pointer initially pointing to an
 286   // accessor resolution function gets called for each access. Upon first invocation,
 287   // it resolves which accessor to be used in future invocations and patches the
 288   // function pointer to this new accessor.
 289 
 290   template <DecoratorSet decorators, typename T>
 291   void RuntimeDispatch<decorators, T, BARRIER_STORE>::store_init(void* addr, T value) {
 292     func_t function = BarrierResolver<decorators, func_t, BARRIER_STORE>::resolve_barrier();
 293     _store_func = function;
 294     function(addr, value);
 295   }
 296 
 297   template <DecoratorSet decorators, typename T>
 298   void RuntimeDispatch<decorators, T, BARRIER_STORE_AT>::store_at_init(oop base, ptrdiff_t offset, T value) {
 299     func_t function = BarrierResolver<decorators, func_t, BARRIER_STORE_AT>::resolve_barrier();
 300     _store_at_func = function;
 301     function(base, offset, value);
 302   }
 303 
 304   template <DecoratorSet decorators, typename T>
 305   T RuntimeDispatch<decorators, T, BARRIER_LOAD>::load_init(void* addr) {
 306     func_t function = BarrierResolver<decorators, func_t, BARRIER_LOAD>::resolve_barrier();
 307     _load_func = function;
 308     return function(addr);
 309   }
 310 
 311   template <DecoratorSet decorators, typename T>
 312   T RuntimeDispatch<decorators, T, BARRIER_LOAD_AT>::load_at_init(oop base, ptrdiff_t offset) {
 313     func_t function = BarrierResolver<decorators, func_t, BARRIER_LOAD_AT>::resolve_barrier();
 314     _load_at_func = function;
 315     return function(base, offset);
 316   }
 317 
 318   template <DecoratorSet decorators, typename T>
 319   T RuntimeDispatch<decorators, T, BARRIER_ATOMIC_CMPXCHG>::atomic_cmpxchg_init(T new_value, void* addr, T compare_value) {
 320     func_t function = BarrierResolver<decorators, func_t, BARRIER_ATOMIC_CMPXCHG>::resolve_barrier();
 321     _atomic_cmpxchg_func = function;
 322     return function(new_value, addr, compare_value);
 323   }
 324 
 325   template <DecoratorSet decorators, typename T>
 326   T RuntimeDispatch<decorators, T, BARRIER_ATOMIC_CMPXCHG_AT>::atomic_cmpxchg_at_init(T new_value, oop base, ptrdiff_t offset, T compare_value) {
 327     func_t function = BarrierResolver<decorators, func_t, BARRIER_ATOMIC_CMPXCHG_AT>::resolve_barrier();
 328     _atomic_cmpxchg_at_func = function;
 329     return function(new_value, base, offset, compare_value);
 330   }
 331 
 332   template <DecoratorSet decorators, typename T>
 333   T RuntimeDispatch<decorators, T, BARRIER_ATOMIC_XCHG>::atomic_xchg_init(T new_value, void* addr) {
 334     func_t function = BarrierResolver<decorators, func_t, BARRIER_ATOMIC_XCHG>::resolve_barrier();
 335     _atomic_xchg_func = function;
 336     return function(new_value, addr);
 337   }
 338 
 339   template <DecoratorSet decorators, typename T>
 340   T RuntimeDispatch<decorators, T, BARRIER_ATOMIC_XCHG_AT>::atomic_xchg_at_init(T new_value, oop base, ptrdiff_t offset) {
 341     func_t function = BarrierResolver<decorators, func_t, BARRIER_ATOMIC_XCHG_AT>::resolve_barrier();
 342     _atomic_xchg_at_func = function;
 343     return function(new_value, base, offset);
 344   }
 345 
 346   template <DecoratorSet decorators, typename T>
 347   bool RuntimeDispatch<decorators, T, BARRIER_ARRAYCOPY>::arraycopy_init(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
 348                                                                          arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
 349                                                                          size_t length) {
 350     func_t function = BarrierResolver<decorators, func_t, BARRIER_ARRAYCOPY>::resolve_barrier();
 351     _arraycopy_func = function;
 352     return function(src_obj, src_offset_in_bytes, src_raw,
 353                     dst_obj, dst_offset_in_bytes, dst_raw,
 354                     length);
 355   }
 356 
 357   template <DecoratorSet decorators, typename T>
 358   void RuntimeDispatch<decorators, T, BARRIER_CLONE>::clone_init(oop src, oop dst, size_t size) {
 359     func_t function = BarrierResolver<decorators, func_t, BARRIER_CLONE>::resolve_barrier();
 360     _clone_func = function;
 361     function(src, dst, size);
 362   }
 363 
 364   template <DecoratorSet decorators, typename T>
 365   oop RuntimeDispatch<decorators, T, BARRIER_RESOLVE>::resolve_init(oop obj) {
 366     func_t function = BarrierResolver<decorators, func_t, BARRIER_RESOLVE>::resolve_barrier();
 367     _resolve_func = function;
 368     return function(obj);
 369   }
 370 
 371   template <DecoratorSet decorators, typename T>
 372   bool RuntimeDispatch<decorators, T, BARRIER_EQUALS>::equals_init(oop o1, oop o2) {
 373     func_t function = BarrierResolver<decorators, func_t, BARRIER_EQUALS>::resolve_barrier();
 374     _equals_func = function;
 375     return function(o1, o2);
 376   }
 377 }
 378 
 379 #endif // SHARE_OOPS_ACCESS_INLINE_HPP