1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   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.
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   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  *
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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_OOPS_OBJARRAYKLASS_HPP
  26 #define SHARE_VM_OOPS_OBJARRAYKLASS_HPP
  27 
  28 #include "classfile/classLoaderData.hpp"
  29 #include "oops/arrayKlass.hpp"
  30 #include "utilities/macros.hpp"
  31 
  32 // ObjArrayKlass is the klass for objArrays
  33 
  34 class ObjArrayKlass : public ArrayKlass {
  35   friend class VMStructs;
  36   friend class JVMCIVMStructs;
  37  private:
  38   // If you add a new field that points to any metaspace object, you
  39   // must add this field to ObjArrayKlass::metaspace_pointers_do().
  40   Klass* _element_klass;            // The klass of the elements of this array type
  41   Klass* _bottom_klass;             // The one-dimensional type (InstanceKlass or TypeArrayKlass)
  42 
  43   // Constructor
  44   ObjArrayKlass(int n, Klass* element_klass, Symbol* name);
  45   static ObjArrayKlass* allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS);
  46  public:
  47   // For dummy objects
  48   ObjArrayKlass() {}
  49 
  50   // Instance variables
  51   Klass* element_klass() const      { return _element_klass; }
  52   void set_element_klass(Klass* k)  { _element_klass = k; }
  53   Klass** element_klass_addr()      { return &_element_klass; }
  54 
  55   Klass* bottom_klass() const       { return _bottom_klass; }
  56   void set_bottom_klass(Klass* k)   { _bottom_klass = k; }
  57   Klass** bottom_klass_addr()       { return &_bottom_klass; }
  58 
  59   ModuleEntry* module() const;
  60   PackageEntry* package() const;
  61 
  62   // Compiler/Interpreter offset
  63   static ByteSize element_klass_offset() { return in_ByteSize(offset_of(ObjArrayKlass, _element_klass)); }
  64 
  65   // Dispatched operation
  66   bool can_be_primary_super_slow() const;
  67   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
  68   bool compute_is_subtype_of(Klass* k);
  69   DEBUG_ONLY(bool is_objArray_klass_slow()  const  { return true; })
  70   int oop_size(oop obj) const;
  71 
  72   // Allocation
  73   static Klass* allocate_objArray_klass(ClassLoaderData* loader_data,
  74                                           int n, Klass* element_klass, TRAPS);
  75 
  76   objArrayOop allocate(int length, TRAPS);
  77   oop multi_allocate(int rank, jint* sizes, TRAPS);
  78 
  79   // Copying
  80   void  copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS);
  81 
  82   // Compute protection domain
  83   oop protection_domain() const { return bottom_klass()->protection_domain(); }
  84 
  85   virtual void metaspace_pointers_do(MetaspaceClosure* iter);
  86 
  87  private:
  88   // Either oop or narrowOop depending on UseCompressedOops.
  89   // must be called from within ObjArrayKlass.cpp
  90   template <class T> void do_copy(arrayOop s, size_t src_offset,
  91                                   arrayOop d, size_t dst_offset,
  92                                   int length, TRAPS);
  93  protected:
  94   // Returns the ObjArrayKlass for n'th dimension.
  95   virtual Klass* array_klass_impl(bool or_null, int n, TRAPS);
  96 
  97   // Returns the array class with this class as element type.
  98   virtual Klass* array_klass_impl(bool or_null, TRAPS);
  99 
 100  public:
 101 
 102   static ObjArrayKlass* cast(Klass* k) {
 103     return const_cast<ObjArrayKlass*>(cast(const_cast<const Klass*>(k)));
 104   }
 105 
 106   static const ObjArrayKlass* cast(const Klass* k) {
 107     assert(k->is_objArray_klass(), "cast to ObjArrayKlass");
 108     return static_cast<const ObjArrayKlass*>(k);
 109   }
 110 
 111   // Sizing
 112   static int header_size()                { return sizeof(ObjArrayKlass)/wordSize; }
 113   int size() const                        { return ArrayKlass::static_size(header_size()); }
 114 
 115   // Initialization (virtual from Klass)
 116   void initialize(TRAPS);
 117 
 118   // GC specific object visitors
 119   //
 120 #if INCLUDE_ALL_GCS
 121   // Parallel Scavenge
 122   void oop_ps_push_contents(  oop obj, PSPromotionManager* pm);
 123   // Parallel Compact
 124   void oop_pc_follow_contents(oop obj, ParCompactionManager* cm);
 125   void oop_pc_update_pointers(oop obj, ParCompactionManager* cm);
 126 #endif
 127 
 128   // Oop fields (and metadata) iterators
 129   //  [nv = true]  Use non-virtual calls to do_oop_nv.
 130   //  [nv = false] Use virtual calls to do_oop.
 131   //
 132   // The ObjArrayKlass iterators also visits the Object's klass.
 133 
 134  private:
 135 
 136   // Iterate over oop elements and metadata.
 137   template <bool nv, typename OopClosureType>
 138   inline void oop_oop_iterate(oop obj, OopClosureType* closure);
 139 
 140   // Iterate over oop elements within mr, and metadata.
 141   template <bool nv, typename OopClosureType>
 142   inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
 143 
 144   // Iterate over oop elements with indices within [start, end), and metadata.
 145   template <bool nv, class OopClosureType>
 146   inline void oop_oop_iterate_range(oop obj, OopClosureType* closure, int start, int end);
 147 
 148   // Iterate over oop elements within [start, end), and metadata.
 149   // Specialized for [T = oop] or [T = narrowOop].
 150   template <bool nv, typename T, class OopClosureType>
 151   inline void oop_oop_iterate_range_specialized(objArrayOop a, OopClosureType* closure, int start, int end);
 152 
 153  public:
 154   // Iterate over all oop elements.
 155   template <bool nv, class OopClosureType>
 156   inline void oop_oop_iterate_elements(objArrayOop a, OopClosureType* closure);
 157 
 158  private:
 159   // Iterate over all oop elements.
 160   // Specialized for [T = oop] or [T = narrowOop].
 161   template <bool nv, typename T, class OopClosureType>
 162   inline void oop_oop_iterate_elements_specialized(objArrayOop a, OopClosureType* closure);
 163 
 164   // Iterate over all oop elements with indices within mr.
 165   template <bool nv, class OopClosureType>
 166   inline void oop_oop_iterate_elements_bounded(objArrayOop a, OopClosureType* closure, MemRegion mr);
 167 
 168   // Iterate over oop elements within [low, high)..
 169   // Specialized for [T = oop] or [T = narrowOop].
 170   template <bool nv, typename T, class OopClosureType>
 171   inline void oop_oop_iterate_elements_specialized_bounded(objArrayOop a, OopClosureType* closure, void* low, void* high);
 172 
 173 
 174  public:
 175 
 176   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL)
 177   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL)
 178   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL_RANGE)
 179   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL_RANGE)
 180 
 181 #if INCLUDE_ALL_GCS
 182   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL_NO_BACKWARDS)
 183   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL_NO_BACKWARDS)
 184 #endif // INCLUDE_ALL_GCS
 185 
 186   // JVM support
 187   jint compute_modifier_flags(TRAPS) const;
 188 
 189  public:
 190   // Printing
 191   void print_on(outputStream* st) const;
 192   void print_value_on(outputStream* st) const;
 193 
 194   void oop_print_value_on(oop obj, outputStream* st);
 195 #ifndef PRODUCT
 196   void oop_print_on      (oop obj, outputStream* st);
 197 #endif //PRODUCT
 198 
 199   const char* internal_name() const;
 200 
 201   // Verification
 202   void verify_on(outputStream* st);
 203 
 204   void oop_verify_on(oop obj, outputStream* st);
 205 };
 206 
 207 #endif // SHARE_VM_OOPS_OBJARRAYKLASS_HPP