1 /*
   2  * Copyright (c) 1997, 2016, 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.
   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
  21  * questions.
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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   Klass* _element_klass;            // The klass of the elements of this array type
  39   Klass* _bottom_klass;             // The one-dimensional type (InstanceKlass or TypeArrayKlass)
  40 
  41   // Constructor
  42   ObjArrayKlass(int n, KlassHandle element_klass, Symbol* name);
  43   static ObjArrayKlass* allocate(ClassLoaderData* loader_data, int n, KlassHandle klass_handle, Symbol* name, TRAPS);
  44  public:
  45   // For dummy objects
  46   ObjArrayKlass() {}
  47 
  48   // Instance variables
  49   Klass* element_klass() const      { return _element_klass; }
  50   void set_element_klass(Klass* k)  { _element_klass = k; }
  51   Klass** element_klass_addr()      { return &_element_klass; }
  52 
  53   Klass* bottom_klass() const       { return _bottom_klass; }
  54   void set_bottom_klass(Klass* k)   { _bottom_klass = k; }
  55   Klass** bottom_klass_addr()       { return &_bottom_klass; }
  56 
  57   // Compiler/Interpreter offset
  58   static ByteSize element_klass_offset() { return in_ByteSize(offset_of(ObjArrayKlass, _element_klass)); }
  59 
  60   // Dispatched operation
  61   bool can_be_primary_super_slow() const;
  62   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
  63   bool compute_is_subtype_of(Klass* k);
  64   DEBUG_ONLY(bool is_objArray_klass_slow()  const  { return true; })
  65   int oop_size(oop obj) const;
  66 
  67   // Allocation
  68   static Klass* allocate_objArray_klass(ClassLoaderData* loader_data,
  69                                           int n, KlassHandle element_klass, TRAPS);
  70 
  71   objArrayOop allocate(int length, TRAPS);
  72   oop multi_allocate(int rank, jint* sizes, TRAPS);
  73 
  74   // Copying
  75   void  copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS);
  76 
  77   // Compute protection domain
  78   oop protection_domain() const { return bottom_klass()->protection_domain(); }
  79 
  80  private:
  81   // Either oop or narrowOop depending on UseCompressedOops.
  82   // must be called from within ObjArrayKlass.cpp
  83   template <class T> void do_copy(arrayOop s, T* src, arrayOop d,
  84                                   T* dst, int length, TRAPS);
  85  protected:
  86   // Returns the ObjArrayKlass for n'th dimension.
  87   virtual Klass* array_klass_impl(bool or_null, int n, TRAPS);
  88 
  89   // Returns the array class with this class as element type.
  90   virtual Klass* array_klass_impl(bool or_null, TRAPS);
  91 
  92  public:
  93 
  94   static ObjArrayKlass* cast(Klass* k) {
  95     return const_cast<ObjArrayKlass*>(cast(const_cast<const Klass*>(k)));
  96   }
  97 
  98   static const ObjArrayKlass* cast(const Klass* k) {
  99     assert(k->is_objArray_klass(), "cast to ObjArrayKlass");
 100     return static_cast<const ObjArrayKlass*>(k);
 101   }
 102 
 103   // Sizing
 104   static int header_size()                { return sizeof(ObjArrayKlass)/wordSize; }
 105   int size() const                        { return ArrayKlass::static_size(header_size()); }
 106 
 107   // Initialization (virtual from Klass)
 108   void initialize(TRAPS);
 109 
 110   // GC specific object visitors
 111   //
 112   // Mark Sweep
 113   int  oop_ms_adjust_pointers(oop obj);
 114 #if INCLUDE_ALL_GCS
 115   // Parallel Scavenge
 116   void oop_ps_push_contents(  oop obj, PSPromotionManager* pm);
 117   // Parallel Compact
 118   void oop_pc_follow_contents(oop obj, ParCompactionManager* cm);
 119   void oop_pc_update_pointers(oop obj, ParCompactionManager* cm);
 120 #endif
 121 
 122   // Oop fields (and metadata) iterators
 123   //  [nv = true]  Use non-virtual calls to do_oop_nv.
 124   //  [nv = false] Use virtual calls to do_oop.
 125   //
 126   // The ObjArrayKlass iterators also visits the Object's klass.
 127 
 128  private:
 129 
 130   // Iterate over oop elements and metadata.
 131   template <bool nv, typename OopClosureType>
 132   inline void oop_oop_iterate(oop obj, OopClosureType* closure);
 133 
 134   // Iterate over oop elements within mr, and metadata.
 135   template <bool nv, typename OopClosureType>
 136   inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
 137 
 138   // Iterate over oop elements with indices within [start, end), and metadata.
 139   template <bool nv, class OopClosureType>
 140   inline void oop_oop_iterate_range(oop obj, OopClosureType* closure, int start, int end);
 141 
 142   // Iterate over oop elements within [start, end), and metadata.
 143   // Specialized for [T = oop] or [T = narrowOop].
 144   template <bool nv, typename T, class OopClosureType>
 145   inline void oop_oop_iterate_range_specialized(objArrayOop a, OopClosureType* closure, int start, int end);
 146 
 147  public:
 148   // Iterate over all oop elements.
 149   template <bool nv, class OopClosureType>
 150   inline void oop_oop_iterate_elements(objArrayOop a, OopClosureType* closure);
 151 
 152  private:
 153   // Iterate over all oop elements.
 154   // Specialized for [T = oop] or [T = narrowOop].
 155   template <bool nv, typename T, class OopClosureType>
 156   inline void oop_oop_iterate_elements_specialized(objArrayOop a, OopClosureType* closure);
 157 
 158   // Iterate over all oop elements with indices within mr.
 159   template <bool nv, class OopClosureType>
 160   inline void oop_oop_iterate_elements_bounded(objArrayOop a, OopClosureType* closure, MemRegion mr);
 161 
 162   // Iterate over oop elements within [low, high)..
 163   // Specialized for [T = oop] or [T = narrowOop].
 164   template <bool nv, typename T, class OopClosureType>
 165   inline void oop_oop_iterate_elements_specialized_bounded(objArrayOop a, OopClosureType* closure, void* low, void* high);
 166 
 167 
 168  public:
 169 
 170   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL)
 171   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL)
 172   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL_RANGE)
 173   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL_RANGE)
 174 
 175 #if INCLUDE_ALL_GCS
 176   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL_NO_BACKWARDS)
 177   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL_NO_BACKWARDS)
 178 #endif // INCLUDE_ALL_GCS
 179 
 180   // JVM support
 181   jint compute_modifier_flags(TRAPS) const;
 182 
 183  public:
 184   // Printing
 185   void print_on(outputStream* st) const;
 186   void print_value_on(outputStream* st) const;
 187 
 188   void oop_print_value_on(oop obj, outputStream* st);
 189 #ifndef PRODUCT
 190   void oop_print_on      (oop obj, outputStream* st);
 191 #endif //PRODUCT
 192 
 193   const char* internal_name() const;
 194 
 195   // Verification
 196   void verify_on(outputStream* st);
 197 
 198   void oop_verify_on(oop obj, outputStream* st);
 199 };
 200 
 201 #endif // SHARE_VM_OOPS_OBJARRAYKLASS_HPP