1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   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.
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  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_VM_OOPS_ARRAYKLASS_HPP
  26 #define SHARE_VM_OOPS_ARRAYKLASS_HPP
  27 
  28 #include "memory/universe.hpp"
  29 #include "oops/klass.hpp"
  30 
  31 class fieldDescriptor;
  32 class klassVtable;
  33 
  34 // ArrayKlass is the abstract baseclass for all array classes
  35 
  36 class ArrayKlass: public Klass {
  37   friend class VMStructs;
  38  private:
  39   // If you add a new field that points to any metaspace object, you
  40   // must add this field to ArrayKlass::metaspace_pointers_do().
  41   int      _dimension;         // This is n'th-dimensional array.
  42   Klass* volatile _higher_dimension;  // Refers the (n+1)'th-dimensional array (if present).
  43   Klass* volatile _lower_dimension;   // Refers the (n-1)'th-dimensional array (if present).
  44 
  45  protected:
  46   // Constructors
  47   // The constructor with the Symbol argument does the real array
  48   // initialization, the other is a dummy
  49   ArrayKlass(Symbol* name);
  50   ArrayKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for cds"); }
  51 
  52  public:
  53   // Testing operation
  54   DEBUG_ONLY(bool is_array_klass_slow() const { return true; })
  55 
  56   // Instance variables
  57   int dimension() const                 { return _dimension;      }
  58   void set_dimension(int dimension)     { _dimension = dimension; }
  59 
  60   Klass* higher_dimension() const     { return _higher_dimension; }
  61   inline Klass* higher_dimension_acquire() const; // load with acquire semantics
  62   void set_higher_dimension(Klass* k) { _higher_dimension = k; }
  63   inline void release_set_higher_dimension(Klass* k); // store with release semantics
  64   Klass** adr_higher_dimension()      { return (Klass**)&this->_higher_dimension;}
  65 
  66   Klass* lower_dimension() const      { return _lower_dimension; }
  67   void set_lower_dimension(Klass* k)  { _lower_dimension = k; }
  68   Klass** adr_lower_dimension()       { return (Klass**)&this->_lower_dimension;}
  69 
  70   // offset of first element, including any padding for the sake of alignment
  71   int  array_header_in_bytes() const    { return layout_helper_header_size(layout_helper()); }
  72   int  log2_element_size() const        { return layout_helper_log2_element_size(layout_helper()); }
  73   // type of elements (T_OBJECT for both oop arrays and array-arrays)
  74   BasicType element_type() const        { return layout_helper_element_type(layout_helper()); }
  75 
  76   virtual Klass* java_super() const;//{ return SystemDictionary::Object_klass(); }
  77 
  78   // Allocation
  79   // Sizes points to the first dimension of the array, subsequent dimensions
  80   // are always in higher memory.  The callers of these set that up.
  81   virtual oop multi_allocate(int rank, jint* sizes, TRAPS);
  82   objArrayOop allocate_arrayArray(int n, int length, TRAPS);
  83 
  84   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
  85   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
  86 
  87   // Lookup operations
  88   Method* uncached_lookup_method(const Symbol* name,
  89                                  const Symbol* signature,
  90                                  OverpassLookupMode overpass_mode) const;
  91 
  92   static ArrayKlass* cast(Klass* k) {
  93     return const_cast<ArrayKlass*>(cast(const_cast<const Klass*>(k)));
  94   }
  95 
  96   static const ArrayKlass* cast(const Klass* k) {
  97     assert(k->is_array_klass(), "cast to ArrayKlass");
  98     return static_cast<const ArrayKlass*>(k);
  99   }
 100 
 101   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
 102                                                   Array<Klass*>* transitive_interfaces);
 103   bool compute_is_subtype_of(Klass* k);
 104 
 105   // Sizing
 106   static int static_size(int header_size);
 107 
 108   virtual void metaspace_pointers_do(MetaspaceClosure* iter);
 109 
 110 #if INCLUDE_SERVICES
 111   virtual void collect_statistics(KlassSizeStats *sz) const {
 112     Klass::collect_statistics(sz);
 113     // Do nothing for now, but remember to modify if you add new
 114     // stuff to ArrayKlass.
 115   }
 116 #endif
 117 
 118   // Iterators
 119   void array_klasses_do(void f(Klass* k));
 120   void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
 121 
 122   // Return a handle.
 123   static void     complete_create_array_klass(ArrayKlass* k, Klass* super_klass, ModuleEntry* module, TRAPS);
 124 
 125 
 126   // jvm support
 127   jint compute_modifier_flags(TRAPS) const;
 128 
 129   // JVMTI support
 130   jint jvmti_class_status() const;
 131 
 132   // CDS support - remove and restore oops from metadata. Oops are not shared.
 133   virtual void remove_unshareable_info();
 134   virtual void remove_java_mirror();
 135   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
 136 
 137   // Printing
 138   void print_on(outputStream* st) const;
 139   void print_value_on(outputStream* st) const;
 140 
 141   void oop_print_on(oop obj, outputStream* st);
 142 
 143   // Verification
 144   void verify_on(outputStream* st);
 145 
 146   void oop_verify_on(oop obj, outputStream* st);
 147 };
 148 
 149 // Array oop iteration macros for declarations.
 150 // Used to generate the declarations in the *ArrayKlass header files.
 151 
 152 #define OOP_OOP_ITERATE_DECL_RANGE(OopClosureType, nv_suffix)                                   \
 153   void oop_oop_iterate_range##nv_suffix(oop obj, OopClosureType* closure, int start, int end);
 154 
 155 #if INCLUDE_OOP_OOP_ITERATE_BACKWARDS
 156 // Named NO_BACKWARDS because the definition used by *ArrayKlass isn't reversed, see below.
 157 #define OOP_OOP_ITERATE_DECL_NO_BACKWARDS(OopClosureType, nv_suffix)            \
 158   void oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* closure);
 159 #endif
 160 
 161 
 162 // Array oop iteration macros for definitions.
 163 // Used to generate the definitions in the *ArrayKlass.inline.hpp files.
 164 
 165 #define OOP_OOP_ITERATE_DEFN_RANGE(KlassType, OopClosureType, nv_suffix)                                  \
 166                                                                                                           \
 167 void KlassType::oop_oop_iterate_range##nv_suffix(oop obj, OopClosureType* closure, int start, int end) {  \
 168   oop_oop_iterate_range<nvs_to_bool(nv_suffix)>(obj, closure, start, end);                                \
 169 }
 170 
 171 #if INCLUDE_OOP_OOP_ITERATE_BACKWARDS
 172 #define OOP_OOP_ITERATE_DEFN_NO_BACKWARDS(KlassType, OopClosureType, nv_suffix)           \
 173 void KlassType::oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* closure) {  \
 174   /* No reverse implementation ATM. */                                                    \
 175   oop_oop_iterate<nvs_to_bool(nv_suffix)>(obj, closure);                                  \
 176 }
 177 #else
 178 #define OOP_OOP_ITERATE_DEFN_NO_BACKWARDS(KlassType, OopClosureType, nv_suffix)
 179 #endif
 180 
 181 #endif // SHARE_VM_OOPS_ARRAYKLASS_HPP