rev 50331 : 8198285: More consistent Access API for arraycopy

   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
   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).
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  24 
  25 #ifndef SHARE_VM_GC_SHARED_BARRIERSET_HPP
  26 #define SHARE_VM_GC_SHARED_BARRIERSET_HPP
  27 
  28 #include "gc/shared/barrierSetConfig.hpp"
  29 #include "memory/memRegion.hpp"
  30 #include "oops/access.hpp"
  31 #include "oops/accessBackend.hpp"
  32 #include "oops/oopsHierarchy.hpp"
  33 #include "utilities/fakeRttiSupport.hpp"
  34 #include "utilities/macros.hpp"
  35 
  36 class BarrierSetAssembler;
  37 class BarrierSetC1;
  38 class BarrierSetC2;
  39 class JavaThread;
  40 
  41 // This class provides the interface between a barrier implementation and
  42 // the rest of the system.
  43 
  44 class BarrierSet: public CHeapObj<mtGC> {
  45   friend class VMStructs;
  46 
  47   static BarrierSet* _barrier_set;
  48 
  49 public:
  50   enum Name {
  51 #define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
  52     FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
  53 #undef BARRIER_SET_DECLARE_BS_ENUM
  54     UnknownBS
  55   };
  56 
  57 protected:
  58   // Fake RTTI support.  For a derived class T to participate
  59   // - T must have a corresponding Name entry.
  60   // - GetName<T> must be specialized to return the corresponding Name
  61   //   entry.
  62   // - If T is a base class, the constructor must have a FakeRtti
  63   //   parameter and pass it up to its base class, with the tag set
  64   //   augmented with the corresponding Name entry.
  65   // - If T is a concrete class, the constructor must create a
  66   //   FakeRtti object whose tag set includes the corresponding Name
  67   //   entry, and pass it up to its base class.
  68   typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
  69 
  70 private:
  71   FakeRtti _fake_rtti;
  72   BarrierSetAssembler* _barrier_set_assembler;
  73   BarrierSetC1* _barrier_set_c1;
  74   BarrierSetC2* _barrier_set_c2;
  75 
  76 public:
  77   // Metafunction mapping a class derived from BarrierSet to the
  78   // corresponding Name enum tag.
  79   template<typename T> struct GetName;
  80 
  81   // Metafunction mapping a Name enum type to the corresponding
  82   // lass derived from BarrierSet.
  83   template<BarrierSet::Name T> struct GetType;
  84 
  85   // Note: This is not presently the Name corresponding to the
  86   // concrete class of this object.
  87   BarrierSet::Name kind() const { return _fake_rtti.concrete_tag(); }
  88 
  89   // Test whether this object is of the type corresponding to bsn.
  90   bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
  91 
  92   // End of fake RTTI support.
  93 
  94 protected:
  95   BarrierSet(BarrierSetAssembler* barrier_set_assembler,
  96              BarrierSetC1* barrier_set_c1,
  97              BarrierSetC2* barrier_set_c2,
  98              const FakeRtti& fake_rtti) :
  99     _fake_rtti(fake_rtti),
 100     _barrier_set_assembler(barrier_set_assembler),
 101     _barrier_set_c1(barrier_set_c1),
 102     _barrier_set_c2(barrier_set_c2) {}
 103   ~BarrierSet() { }
 104 
 105   template <class BarrierSetAssemblerT>
 106   BarrierSetAssembler* make_barrier_set_assembler() {
 107     return NOT_ZERO(new BarrierSetAssemblerT()) ZERO_ONLY(NULL);
 108   }
 109 
 110   template <class BarrierSetC1T>
 111   BarrierSetC1* make_barrier_set_c1() {
 112     return COMPILER1_PRESENT(new BarrierSetC1T()) NOT_COMPILER1(NULL);
 113   }
 114 
 115   template <class BarrierSetC2T>
 116   BarrierSetC2* make_barrier_set_c2() {
 117     return COMPILER2_PRESENT(new BarrierSetC2T()) NOT_COMPILER2(NULL);
 118   }
 119 
 120 public:
 121   // Support for optimizing compilers to call the barrier set on slow path allocations
 122   // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks.
 123   // The allocation is safe to use iff it returns true. If not, the slow-path allocation
 124   // is redone until it succeeds. This can e.g. prevent allocations from the slow path
 125   // to be in old.
 126   virtual void on_slowpath_allocation_exit(JavaThread* thread, oop new_obj) {}
 127   virtual void on_thread_create(Thread* thread) {}
 128   virtual void on_thread_destroy(Thread* thread) {}
 129   virtual void on_thread_attach(JavaThread* thread) {}
 130   virtual void on_thread_detach(JavaThread* thread) {}
 131   virtual void make_parsable(JavaThread* thread) {}
 132 
 133 public:
 134   // Print a description of the memory for the barrier set
 135   virtual void print_on(outputStream* st) const = 0;
 136 
 137   static BarrierSet* barrier_set() { return _barrier_set; }
 138   static void set_barrier_set(BarrierSet* barrier_set);
 139 
 140   BarrierSetAssembler* barrier_set_assembler() {
 141     assert(_barrier_set_assembler != NULL, "should be set");
 142     return _barrier_set_assembler;
 143   }
 144 
 145   BarrierSetC1* barrier_set_c1() {
 146     assert(_barrier_set_c1 != NULL, "should be set");
 147     return _barrier_set_c1;
 148   }
 149 
 150   BarrierSetC2* barrier_set_c2() {
 151     assert(_barrier_set_c2 != NULL, "should be set");
 152     return _barrier_set_c2;
 153   }
 154 
 155   // The AccessBarrier of a BarrierSet subclass is called by the Access API
 156   // (cf. oops/access.hpp) to perform decorated accesses. GC implementations
 157   // may override these default access operations by declaring an
 158   // AccessBarrier class in its BarrierSet. Its accessors will then be
 159   // automatically resolved at runtime.
 160   //
 161   // In order to register a new FooBarrierSet::AccessBarrier with the Access API,
 162   // the following steps should be taken:
 163   // 1) Provide an enum "name" for the BarrierSet in barrierSetConfig.hpp
 164   // 2) Make sure the barrier set headers are included from barrierSetConfig.inline.hpp
 165   // 3) Provide specializations for BarrierSet::GetName and BarrierSet::GetType.
 166   template <DecoratorSet decorators, typename BarrierSetT>
 167   class AccessBarrier: protected RawAccessBarrier<decorators> {
 168   private:
 169     typedef RawAccessBarrier<decorators> Raw;
 170 
 171   public:
 172     // Primitive heap accesses. These accessors get resolved when
 173     // IN_HEAP is set (e.g. when using the HeapAccess API), it is
 174     // not an oop_* overload, and the barrier strength is AS_NORMAL.
 175     template <typename T>
 176     static T load_in_heap(T* addr) {
 177       return Raw::template load<T>(addr);
 178     }
 179 
 180     template <typename T>
 181     static T load_in_heap_at(oop base, ptrdiff_t offset) {
 182       return Raw::template load_at<T>(base, offset);
 183     }
 184 
 185     template <typename T>
 186     static void store_in_heap(T* addr, T value) {
 187       Raw::store(addr, value);
 188     }
 189 
 190     template <typename T>
 191     static void store_in_heap_at(oop base, ptrdiff_t offset, T value) {
 192       Raw::store_at(base, offset, value);
 193     }
 194 
 195     template <typename T>
 196     static T atomic_cmpxchg_in_heap(T new_value, T* addr, T compare_value) {
 197       return Raw::atomic_cmpxchg(new_value, addr, compare_value);
 198     }
 199 
 200     template <typename T>
 201     static T atomic_cmpxchg_in_heap_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {
 202       return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
 203     }
 204 
 205     template <typename T>
 206     static T atomic_xchg_in_heap(T new_value, T* addr) {
 207       return Raw::atomic_xchg(new_value, addr);
 208     }
 209 
 210     template <typename T>
 211     static T atomic_xchg_in_heap_at(T new_value, oop base, ptrdiff_t offset) {
 212       return Raw::atomic_xchg_at(new_value, base, offset);
 213     }
 214 
 215     template <typename T>
 216     static void arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, const T* src_raw, arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw, size_t length) {
 217       Raw::arraycopy(src_obj, src_offset_in_bytes, src_raw, dst_obj, dst_offset_in_bytes, dst_raw, length);
 218     }
 219 
 220     // Heap oop accesses. These accessors get resolved when
 221     // IN_HEAP is set (e.g. when using the HeapAccess API), it is
 222     // an oop_* overload, and the barrier strength is AS_NORMAL.
 223     template <typename T>
 224     static oop oop_load_in_heap(T* addr) {
 225       return Raw::template oop_load<oop>(addr);
 226     }
 227 
 228     static oop oop_load_in_heap_at(oop base, ptrdiff_t offset) {
 229       return Raw::template oop_load_at<oop>(base, offset);
 230     }
 231 
 232     template <typename T>
 233     static void oop_store_in_heap(T* addr, oop value) {
 234       Raw::oop_store(addr, value);
 235     }
 236 
 237     static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
 238       Raw::oop_store_at(base, offset, value);
 239     }
 240 
 241     template <typename T>
 242     static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
 243       return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
 244     }
 245 
 246     static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
 247       return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
 248     }
 249 
 250     template <typename T>
 251     static oop oop_atomic_xchg_in_heap(oop new_value, T* addr) {
 252       return Raw::oop_atomic_xchg(new_value, addr);
 253     }
 254 
 255     static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
 256       return Raw::oop_atomic_xchg_at(new_value, base, offset);
 257     }
 258 
 259     template <typename T>
 260     static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, const T* src_raw, arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw, size_t length) {
 261       return Raw::oop_arraycopy(src_obj, src_offset_in_bytes, src_raw, dst_obj, dst_offset_in_bytes, dst_raw, length);
 262     }
 263 
 264     // Off-heap oop accesses. These accessors get resolved when
 265     // IN_HEAP is not set (e.g. when using the RootAccess API), it is
 266     // an oop* overload, and the barrier strength is AS_NORMAL.
 267     template <typename T>
 268     static oop oop_load_not_in_heap(T* addr) {
 269       return Raw::template oop_load<oop>(addr);
 270     }
 271 
 272     template <typename T>
 273     static void oop_store_not_in_heap(T* addr, oop value) {
 274       Raw::oop_store(addr, value);
 275     }
 276 
 277     template <typename T>
 278     static oop oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
 279       return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
 280     }
 281 
 282     template <typename T>
 283     static oop oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
 284       return Raw::oop_atomic_xchg(new_value, addr);
 285     }
 286 
 287     // Clone barrier support
 288     static void clone_in_heap(oop src, oop dst, size_t size) {
 289       Raw::clone(src, dst, size);
 290     }
 291 
 292     static oop resolve(oop obj) {
 293       return Raw::resolve(obj);
 294     }
 295 
 296     static bool equals(oop o1, oop o2) {
 297       return Raw::equals(o1, o2);
 298     }
 299   };
 300 };
 301 
 302 template<typename T>
 303 inline T* barrier_set_cast(BarrierSet* bs) {
 304   assert(bs->is_a(BarrierSet::GetName<T>::value), "wrong type of barrier set");
 305   return static_cast<T*>(bs);
 306 }
 307 
 308 #endif // SHARE_VM_GC_SHARED_BARRIERSET_HPP
--- EOF ---