1 /*
   2  * Copyright (c) 1997, 2014, 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.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP
  26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
  27 
  28 #include "classfile/classLoaderData.hpp"
  29 #include "memory/referenceType.hpp"
  30 #include "oops/annotations.hpp"
  31 #include "oops/constMethod.hpp"
  32 #include "oops/fieldInfo.hpp"
  33 #include "oops/instanceOop.hpp"
  34 #include "oops/klassVtable.hpp"
  35 #include "runtime/handles.hpp"
  36 #include "runtime/os.hpp"
  37 #include "utilities/accessFlags.hpp"
  38 #include "utilities/bitMap.inline.hpp"
  39 #include "utilities/macros.hpp"
  40 #include "trace/traceMacros.hpp"
  41 
  42 // An InstanceKlass is the VM level representation of a Java class.
  43 // It contains all information needed for at class at execution runtime.
  44 
  45 //  InstanceKlass embedded field layout (after declared fields):
  46 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  47 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  48 //      The embedded nonstatic oop-map blocks are short pairs (offset, length)
  49 //      indicating where oops are located in instances of this klass.
  50 //    [EMBEDDED implementor of the interface] only exist for interface
  51 //    [EMBEDDED host klass        ] only exist for an anonymous class (JSR 292 enabled)
  52 
  53 
  54 // forward declaration for class -- see below for definition
  55 class SuperTypeClosure;
  56 class JNIid;
  57 class jniIdMapBase;
  58 class BreakpointInfo;
  59 class fieldDescriptor;
  60 class DepChange;
  61 class nmethodBucket;
  62 class JvmtiCachedClassFieldMap;
  63 class MemberNameTable;
  64 
  65 // This is used in iterators below.
  66 class FieldClosure: public StackObj {
  67 public:
  68   virtual void do_field(fieldDescriptor* fd) = 0;
  69 };
  70 
  71 #ifndef PRODUCT
  72 // Print fields.
  73 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
  74 class FieldPrinter: public FieldClosure {
  75    oop _obj;
  76    outputStream* _st;
  77  public:
  78    FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
  79    void do_field(fieldDescriptor* fd);
  80 };
  81 #endif  // !PRODUCT
  82 
  83 // ValueObjs embedded in klass. Describes where oops are located in instances of
  84 // this klass.
  85 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
  86  public:
  87   // Byte offset of the first oop mapped by this block.
  88   int offset() const          { return _offset; }
  89   void set_offset(int offset) { _offset = offset; }
  90 
  91   // Number of oops in this block.
  92   uint count() const         { return _count; }
  93   void set_count(uint count) { _count = count; }
  94 
  95   // sizeof(OopMapBlock) in HeapWords.
  96   static const int size_in_words() {
  97     return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
  98       LogHeapWordSize;
  99   }
 100 
 101  private:
 102   int  _offset;
 103   uint _count;
 104 };
 105 
 106 struct JvmtiCachedClassFileData;
 107 
 108 class InstanceKlass: public Klass {
 109   friend class VMStructs;
 110   friend class ClassFileParser;
 111   friend class CompileReplay;
 112 
 113  protected:
 114   // Constructor
 115   InstanceKlass(int vtable_len,
 116                 int itable_len,
 117                 int static_field_size,
 118                 int nonstatic_oop_map_size,
 119                 ReferenceType rt,
 120                 AccessFlags access_flags,
 121                 bool is_anonymous);
 122  public:
 123   static InstanceKlass* allocate_instance_klass(
 124                                           ClassLoaderData* loader_data,
 125                                           int vtable_len,
 126                                           int itable_len,
 127                                           int static_field_size,
 128                                           int nonstatic_oop_map_size,
 129                                           ReferenceType rt,
 130                                           AccessFlags access_flags,
 131                                           Symbol* name,
 132                                           Klass* super_klass,
 133                                           bool is_anonymous,
 134                                           TRAPS);
 135 
 136   InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
 137 
 138   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 139   // of the class loading & initialization procedure, and the use of the states.
 140   enum ClassState {
 141     allocated,                          // allocated (but not yet linked)
 142     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 143     linked,                             // successfully linked/verified (but not initialized yet)
 144     being_initialized,                  // currently running class initializer
 145     fully_initialized,                  // initialized (successfull final state)
 146     initialization_error                // error happened during initialization
 147   };
 148 
 149   static int number_of_instance_classes() { return _total_instanceKlass_count; }
 150 
 151  private:
 152   static volatile int _total_instanceKlass_count;
 153 
 154  protected:
 155   // Annotations for this class
 156   Annotations*    _annotations;
 157   // Array classes holding elements of this class.
 158   Klass*          _array_klasses;
 159   // Constant pool for this class.
 160   ConstantPool* _constants;
 161   // The InnerClasses attribute and EnclosingMethod attribute. The
 162   // _inner_classes is an array of shorts. If the class has InnerClasses
 163   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 164   // [inner_class_info_index, outer_class_info_index,
 165   // inner_name_index, inner_class_access_flags] for the InnerClasses
 166   // attribute. If the EnclosingMethod attribute exists, it occupies the
 167   // last two shorts [class_index, method_index] of the array. If only
 168   // the InnerClasses attribute exists, the _inner_classes array length is
 169   // number_of_inner_classes * 4. If the class has both InnerClasses
 170   // and EnclosingMethod attributes the _inner_classes array length is
 171   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 172   Array<jushort>* _inner_classes;
 173 
 174   // the source debug extension for this klass, NULL if not specified.
 175   // Specified as UTF-8 string without terminating zero byte in the classfile,
 176   // it is stored in the instanceklass as a NULL-terminated UTF-8 string
 177   char*           _source_debug_extension;
 178   // Array name derived from this class which needs unreferencing
 179   // if this class is unloaded.
 180   Symbol*         _array_name;
 181 
 182   // Number of heapOopSize words used by non-static fields in this klass
 183   // (including inherited fields but after header_size()).
 184   int             _nonstatic_field_size;
 185   int             _static_field_size;    // number words used by static fields (oop and non-oop) in this klass
 186   // Constant pool index to the utf8 entry of the Generic signature,
 187   // or 0 if none.
 188   u2              _generic_signature_index;
 189   // Constant pool index to the utf8 entry for the name of source file
 190   // containing this klass, 0 if not specified.
 191   u2              _source_file_name_index;
 192   u2              _static_oop_field_count;// number of static oop fields in this klass
 193   u2              _java_fields_count;    // The number of declared Java fields
 194   int             _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
 195 
 196   // _is_marked_dependent can be set concurrently, thus cannot be part of the
 197   // _misc_flags.
 198   bool            _is_marked_dependent;  // used for marking during flushing and deoptimization
 199   bool            _has_unloaded_dependent;
 200 
 201   enum {
 202     _misc_rewritten                = 1 << 0, // methods rewritten.
 203     _misc_has_nonstatic_fields     = 1 << 1, // for sizing with UseCompressedOops
 204     _misc_should_verify_class      = 1 << 2, // allow caching of preverification
 205     _misc_is_anonymous             = 1 << 3, // has embedded _host_klass field
 206     _misc_is_contended             = 1 << 4, // marked with contended annotation
 207     _misc_has_default_methods      = 1 << 5, // class/superclass/implemented interfaces has default methods
 208     _misc_declares_default_methods = 1 << 6, // directly declares default methods (any access)
 209     _misc_has_been_redefined       = 1 << 7  // class has been redefined
 210   };
 211   u2              _misc_flags;
 212   u2              _minor_version;        // minor version number of class file
 213   u2              _major_version;        // major version number of class file
 214   Thread*         _init_thread;          // Pointer to current thread doing initialization (to handle recusive initialization)
 215   int             _vtable_len;           // length of Java vtable (in words)
 216   int             _itable_len;           // length of Java itable (in words)
 217   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 218   MemberNameTable* _member_names;        // Member names
 219   JNIid*          _jni_ids;              // First JNI identifier for static fields in this class
 220   jmethodID*      _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or NULL if none
 221   nmethodBucket*  _dependencies;         // list of dependent nmethods
 222   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 223   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 224   // Linked instanceKlasses of previous versions
 225   InstanceKlass* _previous_versions;
 226   // JVMTI fields can be moved to their own structure - see 6315920
 227   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 228   JvmtiCachedClassFileData* _cached_class_file;
 229 
 230   volatile u2     _idnum_allocated_count;         // JNI/JVMTI: increments with the addition of methods, old ids don't change
 231 
 232   // Class states are defined as ClassState (see above).
 233   // Place the _init_state here to utilize the unused 2-byte after
 234   // _idnum_allocated_count.
 235   u1              _init_state;                    // state of class
 236   u1              _reference_type;                // reference type
 237 
 238   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 239 
 240   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 241 
 242   // Method array.
 243   Array<Method*>* _methods;
 244   // Default Method Array, concrete methods inherited from interfaces
 245   Array<Method*>* _default_methods;
 246   // Interface (Klass*s) this class declares locally to implement.
 247   Array<Klass*>* _local_interfaces;
 248   // Interface (Klass*s) this class implements transitively.
 249   Array<Klass*>* _transitive_interfaces;
 250   // Int array containing the original order of method in the class file (for JVMTI).
 251   Array<int>*     _method_ordering;
 252   // Int array containing the vtable_indices for default_methods
 253   // offset matches _default_methods offset
 254   Array<int>*     _default_vtable_indices;
 255 
 256   // Instance and static variable information, starts with 6-tuples of shorts
 257   // [access, name index, sig index, initval index, low_offset, high_offset]
 258   // for all fields, followed by the generic signature data at the end of
 259   // the array. Only fields with generic signature attributes have the generic
 260   // signature data set in the array. The fields array looks like following:
 261   //
 262   // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
 263   // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
 264   //      ...
 265   // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
 266   //     [generic signature index]
 267   //     [generic signature index]
 268   //     ...
 269   Array<u2>*      _fields;
 270 
 271   // embedded Java vtable follows here
 272   // embedded Java itables follows here
 273   // embedded static fields follows here
 274   // embedded nonstatic oop-map blocks follows here
 275   // embedded implementor of this interface follows here
 276   //   The embedded implementor only exists if the current klass is an
 277   //   iterface. The possible values of the implementor fall into following
 278   //   three cases:
 279   //     NULL: no implementor.
 280   //     A Klass* that's not itself: one implementor.
 281   //     Itself: more than one implementors.
 282   // embedded host klass follows here
 283   //   The embedded host klass only exists in an anonymous class for
 284   //   dynamic language support (JSR 292 enabled). The host class grants
 285   //   its access privileges to this class also. The host class is either
 286   //   named, or a previously loaded anonymous class. A non-anonymous class
 287   //   or an anonymous class loaded through normal classloading does not
 288   //   have this embedded field.
 289   //
 290 
 291   friend class SystemDictionary;
 292 
 293  public:
 294   bool has_nonstatic_fields() const        {
 295     return (_misc_flags & _misc_has_nonstatic_fields) != 0;
 296   }
 297   void set_has_nonstatic_fields(bool b)    {
 298     if (b) {
 299       _misc_flags |= _misc_has_nonstatic_fields;
 300     } else {
 301       _misc_flags &= ~_misc_has_nonstatic_fields;
 302     }
 303   }
 304 
 305   // field sizes
 306   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 307   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 308 
 309   int static_field_size() const            { return _static_field_size; }
 310   void set_static_field_size(int size)     { _static_field_size = size; }
 311 
 312   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 313   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 314 
 315   // Java vtable
 316   int  vtable_length() const               { return _vtable_len; }
 317   void set_vtable_length(int len)          { _vtable_len = len; }
 318 
 319   // Java itable
 320   int  itable_length() const               { return _itable_len; }
 321   void set_itable_length(int len)          { _itable_len = len; }
 322 
 323   // array klasses
 324   Klass* array_klasses() const             { return _array_klasses; }
 325   void set_array_klasses(Klass* k)         { _array_klasses = k; }
 326 
 327   // methods
 328   Array<Method*>* methods() const          { return _methods; }
 329   void set_methods(Array<Method*>* a)      { _methods = a; }
 330   Method* method_with_idnum(int idnum);
 331 
 332   // method ordering
 333   Array<int>* method_ordering() const     { return _method_ordering; }
 334   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 335   void copy_method_ordering(intArray* m, TRAPS);
 336 
 337   // default_methods
 338   Array<Method*>* default_methods() const  { return _default_methods; }
 339   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 340 
 341   // default method vtable_indices
 342   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 343   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 344   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 345 
 346   // interfaces
 347   Array<Klass*>* local_interfaces() const          { return _local_interfaces; }
 348   void set_local_interfaces(Array<Klass*>* a)      {
 349     guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
 350     _local_interfaces = a; }
 351 
 352   Array<Klass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 353   void set_transitive_interfaces(Array<Klass*>* a) {
 354     guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
 355     _transitive_interfaces = a;
 356   }
 357 
 358  private:
 359   friend class fieldDescriptor;
 360   FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
 361 
 362  public:
 363   int     field_offset      (int index) const { return field(index)->offset(); }
 364   int     field_access_flags(int index) const { return field(index)->access_flags(); }
 365   Symbol* field_name        (int index) const { return field(index)->name(constants()); }
 366   Symbol* field_signature   (int index) const { return field(index)->signature(constants()); }
 367 
 368   // Number of Java declared fields
 369   int java_fields_count() const           { return (int)_java_fields_count; }
 370 
 371   Array<u2>* fields() const            { return _fields; }
 372   void set_fields(Array<u2>* f, u2 java_fields_count) {
 373     guarantee(_fields == NULL || f == NULL, "Just checking");
 374     _fields = f;
 375     _java_fields_count = java_fields_count;
 376   }
 377 
 378   // inner classes
 379   Array<u2>* inner_classes() const       { return _inner_classes; }
 380   void set_inner_classes(Array<u2>* f)   { _inner_classes = f; }
 381 
 382   enum InnerClassAttributeOffset {
 383     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 384     inner_class_inner_class_info_offset = 0,
 385     inner_class_outer_class_info_offset = 1,
 386     inner_class_inner_name_offset = 2,
 387     inner_class_access_flags_offset = 3,
 388     inner_class_next_offset = 4
 389   };
 390 
 391   enum EnclosingMethodAttributeOffset {
 392     enclosing_method_class_index_offset = 0,
 393     enclosing_method_method_index_offset = 1,
 394     enclosing_method_attribute_size = 2
 395   };
 396 
 397   // method override check
 398   bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
 399 
 400   // package
 401   bool is_same_class_package(Klass* class2);
 402   bool is_same_class_package(oop classloader2, Symbol* classname2);
 403   static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
 404 
 405   // find an enclosing class (defined where original code was, in jvm.cpp!)
 406   Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
 407     instanceKlassHandle self(THREAD, this);
 408     return compute_enclosing_class_impl(self, inner_is_member, THREAD);
 409   }
 410   static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
 411                                                bool* inner_is_member, TRAPS);
 412 
 413   // tell if two classes have the same enclosing class (at package level)
 414   bool is_same_package_member(Klass* class2, TRAPS) {
 415     instanceKlassHandle self(THREAD, this);
 416     return is_same_package_member_impl(self, class2, THREAD);
 417   }
 418   static bool is_same_package_member_impl(instanceKlassHandle self,
 419                                           Klass* class2, TRAPS);
 420 
 421   // initialization state
 422   bool is_loaded() const                   { return _init_state >= loaded; }
 423   bool is_linked() const                   { return _init_state >= linked; }
 424   bool is_initialized() const              { return _init_state == fully_initialized; }
 425   bool is_not_initialized() const          { return _init_state <  being_initialized; }
 426   bool is_being_initialized() const        { return _init_state == being_initialized; }
 427   bool is_in_error_state() const           { return _init_state == initialization_error; }
 428   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 429   ClassState  init_state()                 { return (ClassState)_init_state; }
 430   bool is_rewritten() const                { return (_misc_flags & _misc_rewritten) != 0; }
 431 
 432   // defineClass specified verification
 433   bool should_verify_class() const         {
 434     return (_misc_flags & _misc_should_verify_class) != 0;
 435   }
 436   void set_should_verify_class(bool value) {
 437     if (value) {
 438       _misc_flags |= _misc_should_verify_class;
 439     } else {
 440       _misc_flags &= ~_misc_should_verify_class;
 441     }
 442   }
 443 
 444   // marking
 445   bool is_marked_dependent() const         { return _is_marked_dependent; }
 446   void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
 447 
 448   bool has_unloaded_dependent() const         { return _has_unloaded_dependent; }
 449   void set_has_unloaded_dependent(bool value) { _has_unloaded_dependent = value; }
 450 
 451   // initialization (virtuals from Klass)
 452   bool should_be_initialized() const;  // means that initialize should be called
 453   void initialize(TRAPS);
 454   void link_class(TRAPS);
 455   bool link_class_or_fail(TRAPS); // returns false on failure
 456   void unlink_class();
 457   void rewrite_class(TRAPS);
 458   void link_methods(TRAPS);
 459   Method* class_initializer();
 460 
 461   // set the class to initialized if no static initializer is present
 462   void eager_initialize(Thread *thread);
 463 
 464   // reference type
 465   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 466   void set_reference_type(ReferenceType t) {
 467     assert(t == (u1)t, "overflow");
 468     _reference_type = (u1)t;
 469   }
 470 
 471   static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
 472 
 473   // find local field, returns true if found
 474   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 475   // find field in direct superinterfaces, returns the interface in which the field is defined
 476   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 477   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 478   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 479   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 480   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 481 
 482   // find a non-static or static field given its offset within the class.
 483   bool contains_field_offset(int offset) {
 484     return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
 485   }
 486 
 487   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 488   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 489 
 490   // find a local method (returns NULL if not found)
 491   Method* find_method(Symbol* name, Symbol* signature) const;
 492   static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
 493   static Method* find_instance_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
 494 
 495   // find a local method index in default_methods (returns -1 if not found)
 496   static int find_method_index(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
 497 
 498   // lookup operation (returns NULL if not found)
 499   Method* uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
 500 
 501   // lookup a method in all the interfaces that this class implements
 502   // (returns NULL if not found)
 503   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
 504 
 505   // lookup a method in local defaults then in all interfaces
 506   // (returns NULL if not found)
 507   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 508 
 509   // Find method indices by name.  If a method with the specified name is
 510   // found the index to the first method is returned, and 'end' is filled in
 511   // with the index of first non-name-matching method.  If no method is found
 512   // -1 is returned.
 513   int find_method_by_name(Symbol* name, int* end);
 514   static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
 515 
 516   // constant pool
 517   ConstantPool* constants() const        { return _constants; }
 518   void set_constants(ConstantPool* c)    { _constants = c; }
 519 
 520   // protection domain
 521   oop protection_domain() const;
 522 
 523   // signers
 524   objArrayOop signers() const;
 525 
 526   // host class
 527   Klass* host_klass() const              {
 528     Klass** hk = (Klass**)adr_host_klass();
 529     if (hk == NULL) {
 530       return NULL;
 531     } else {
 532       assert(*hk != NULL, "host klass should always be set if the address is not null");
 533       return *hk;
 534     }
 535   }
 536   void set_host_klass(Klass* host)            {
 537     assert(is_anonymous(), "not anonymous");
 538     Klass** addr = (Klass**)adr_host_klass();
 539     assert(addr != NULL, "no reversed space");
 540     if (addr != NULL) {
 541       *addr = host;
 542     }
 543   }
 544   bool is_anonymous() const                {
 545     return (_misc_flags & _misc_is_anonymous) != 0;
 546   }
 547   void set_is_anonymous(bool value)        {
 548     if (value) {
 549       _misc_flags |= _misc_is_anonymous;
 550     } else {
 551       _misc_flags &= ~_misc_is_anonymous;
 552     }
 553   }
 554 
 555   // Oop that keeps the metadata for this class from being unloaded
 556   // in places where the metadata is stored in other places, like nmethods
 557   oop klass_holder() const {
 558     return is_anonymous() ? java_mirror() : class_loader();
 559   }
 560 
 561   bool is_contended() const                {
 562     return (_misc_flags & _misc_is_contended) != 0;
 563   }
 564   void set_is_contended(bool value)        {
 565     if (value) {
 566       _misc_flags |= _misc_is_contended;
 567     } else {
 568       _misc_flags &= ~_misc_is_contended;
 569     }
 570   }
 571 
 572   // source file name
 573   Symbol* source_file_name() const               {
 574     return (_source_file_name_index == 0) ?
 575       (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
 576   }
 577   u2 source_file_name_index() const              {
 578     return _source_file_name_index;
 579   }
 580   void set_source_file_name_index(u2 sourcefile_index) {
 581     _source_file_name_index = sourcefile_index;
 582   }
 583 
 584   // minor and major version numbers of class file
 585   u2 minor_version() const                 { return _minor_version; }
 586   void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
 587   u2 major_version() const                 { return _major_version; }
 588   void set_major_version(u2 major_version) { _major_version = major_version; }
 589 
 590   // source debug extension
 591   char* source_debug_extension() const     { return _source_debug_extension; }
 592   void set_source_debug_extension(char* array, int length);
 593 
 594   // symbol unloading support (refcount already added)
 595   Symbol* array_name()                     { return _array_name; }
 596   void set_array_name(Symbol* name)        { assert(_array_name == NULL  || name == NULL, "name already created"); _array_name = name; }
 597 
 598   // nonstatic oop-map blocks
 599   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 600     return oop_map_count * OopMapBlock::size_in_words();
 601   }
 602   unsigned int nonstatic_oop_map_count() const {
 603     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 604   }
 605   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 606   void set_nonstatic_oop_map_size(int words) {
 607     _nonstatic_oop_map_size = words;
 608   }
 609 
 610   // RedefineClasses() support for previous versions:
 611   void add_previous_version(instanceKlassHandle ikh, int emcp_method_count);
 612 
 613   InstanceKlass* previous_versions() const { return _previous_versions; }
 614 
 615   bool has_been_redefined() const {
 616     return (_misc_flags & _misc_has_been_redefined) != 0;
 617   }
 618   void set_has_been_redefined() {
 619     _misc_flags |= _misc_has_been_redefined;
 620   }
 621 
 622   void init_previous_versions() {
 623     _previous_versions = NULL;
 624   }
 625 
 626   static void purge_previous_versions(InstanceKlass* ik);
 627 
 628   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 629   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 630     _cached_class_file = data;
 631   }
 632   JvmtiCachedClassFileData * get_cached_class_file() { return _cached_class_file; }
 633   jint get_cached_class_file_len();
 634   unsigned char * get_cached_class_file_bytes();
 635 
 636   // JVMTI: Support for caching of field indices, types, and offsets
 637   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 638     _jvmti_cached_class_field_map = descriptor;
 639   }
 640   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 641     return _jvmti_cached_class_field_map;
 642   }
 643 
 644   bool has_default_methods() const {
 645     return (_misc_flags & _misc_has_default_methods) != 0;
 646   }
 647   void set_has_default_methods(bool b) {
 648     if (b) {
 649       _misc_flags |= _misc_has_default_methods;
 650     } else {
 651       _misc_flags &= ~_misc_has_default_methods;
 652     }
 653   }
 654 
 655   bool declares_default_methods() const {
 656     return (_misc_flags & _misc_declares_default_methods) != 0;
 657   }
 658   void set_declares_default_methods(bool b) {
 659     if (b) {
 660       _misc_flags |= _misc_declares_default_methods;
 661     } else {
 662       _misc_flags &= ~_misc_declares_default_methods;
 663     }
 664   }
 665 
 666   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 667   inline u2 next_method_idnum();
 668   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 669 
 670   // generics support
 671   Symbol* generic_signature() const                   {
 672     return (_generic_signature_index == 0) ?
 673       (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
 674   }
 675   u2 generic_signature_index() const                  {
 676     return _generic_signature_index;
 677   }
 678   void set_generic_signature_index(u2 sig_index)      {
 679     _generic_signature_index = sig_index;
 680   }
 681 
 682   u2 enclosing_method_data(int offset);
 683   u2 enclosing_method_class_index() {
 684     return enclosing_method_data(enclosing_method_class_index_offset);
 685   }
 686   u2 enclosing_method_method_index() {
 687     return enclosing_method_data(enclosing_method_method_index_offset);
 688   }
 689   void set_enclosing_method_indices(u2 class_index,
 690                                     u2 method_index);
 691 
 692   // jmethodID support
 693   static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
 694                      methodHandle method_h);
 695   static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
 696                      size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
 697                      jmethodID* to_dealloc_id_p,
 698                      jmethodID** to_dealloc_jmeths_p);
 699   static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
 700                 size_t *length_p, jmethodID* id_p);
 701   jmethodID jmethod_id_or_null(Method* method);
 702 
 703   // annotations support
 704   Annotations* annotations() const          { return _annotations; }
 705   void set_annotations(Annotations* anno)   { _annotations = anno; }
 706 
 707   AnnotationArray* class_annotations() const {
 708     return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
 709   }
 710   Array<AnnotationArray*>* fields_annotations() const {
 711     return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
 712   }
 713   AnnotationArray* class_type_annotations() const {
 714     return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
 715   }
 716   Array<AnnotationArray*>* fields_type_annotations() const {
 717     return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
 718   }
 719   // allocation
 720   instanceOop allocate_instance(TRAPS);
 721 
 722   // additional member function to return a handle
 723   instanceHandle allocate_instance_handle(TRAPS)      { return instanceHandle(THREAD, allocate_instance(THREAD)); }
 724 
 725   objArrayOop allocate_objArray(int n, int length, TRAPS);
 726   // Helper function
 727   static instanceOop register_finalizer(instanceOop i, TRAPS);
 728 
 729   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 730   // if not, throw either an Error or an Exception.
 731   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
 732 
 733   // initialization
 734   void call_class_initializer(TRAPS);
 735   void set_initialization_state_and_notify(ClassState state, TRAPS);
 736 
 737   // OopMapCache support
 738   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 739   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 740   void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
 741 
 742   // JNI identifier support (for static fields - for jni performance)
 743   JNIid* jni_ids()                               { return _jni_ids; }
 744   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 745   JNIid* jni_id_for(int offset);
 746 
 747   // maintenance of deoptimization dependencies
 748   int mark_dependent_nmethods(DepChange& changes);
 749   void add_dependent_nmethod(nmethod* nm);
 750   void remove_dependent_nmethod(nmethod* nm);
 751 
 752   // On-stack replacement support
 753   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 754   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 755   void add_osr_nmethod(nmethod* n);
 756   void remove_osr_nmethod(nmethod* n);
 757   int mark_osr_nmethods(const Method* m);
 758   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 759 
 760   // Breakpoint support (see methods on Method* for details)
 761   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 762   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 763 
 764   // support for stub routines
 765   static ByteSize init_state_offset()  { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
 766   TRACE_DEFINE_OFFSET;
 767   static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
 768 
 769   // subclass/subinterface checks
 770   bool implements_interface(Klass* k) const;
 771   bool is_same_or_direct_interface(Klass* k) const;
 772 
 773 #ifdef ASSERT
 774   // check whether this class or one of its superclasses was redefined
 775   bool has_redefined_this_or_super() const;
 776 #endif
 777 
 778   // Access to the implementor of an interface.
 779   Klass* implementor() const
 780   {
 781     Klass** k = adr_implementor();
 782     if (k == NULL) {
 783       return NULL;
 784     } else {
 785       return *k;
 786     }
 787   }
 788 
 789   void set_implementor(Klass* k) {
 790     assert(is_interface(), "not interface");
 791     Klass** addr = adr_implementor();
 792     assert(addr != NULL, "null addr");
 793     if (addr != NULL) {
 794       *addr = k;
 795     }
 796   }
 797 
 798   int  nof_implementors() const       {
 799     Klass* k = implementor();
 800     if (k == NULL) {
 801       return 0;
 802     } else if (k != this) {
 803       return 1;
 804     } else {
 805       return 2;
 806     }
 807   }
 808 
 809   void add_implementor(Klass* k);  // k is a new class that implements this interface
 810   void init_implementor();           // initialize
 811 
 812   // link this class into the implementors list of every interface it implements
 813   void process_interfaces(Thread *thread);
 814 
 815   // virtual operations from Klass
 816   bool is_leaf_class() const               { return _subklass == NULL; }
 817   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
 818   bool compute_is_subtype_of(Klass* k);
 819   bool can_be_primary_super_slow() const;
 820   int oop_size(oop obj)  const             { return size_helper(); }
 821   bool oop_is_instance_slow() const        { return true; }
 822 
 823   // Iterators
 824   void do_local_static_fields(FieldClosure* cl);
 825   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
 826   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
 827 
 828   void methods_do(void f(Method* method));
 829   void array_klasses_do(void f(Klass* k));
 830   void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
 831   bool super_types_do(SuperTypeClosure* blk);
 832 
 833   // Casting from Klass*
 834   static InstanceKlass* cast(Klass* k) {
 835     assert(k == NULL || k->is_klass(), "must be");
 836     assert(k == NULL || k->oop_is_instance(), "cast to InstanceKlass");
 837     return (InstanceKlass*) k;
 838   }
 839 
 840   InstanceKlass* java_super() const {
 841     return (super() == NULL) ? NULL : cast(super());
 842   }
 843 
 844   // Sizing (in words)
 845   static int header_size()            { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
 846 
 847   static int size(int vtable_length, int itable_length,
 848                   int nonstatic_oop_map_size,
 849                   bool is_interface, bool is_anonymous) {
 850     return align_object_size(header_size() +
 851            align_object_offset(vtable_length) +
 852            align_object_offset(itable_length) +
 853            ((is_interface || is_anonymous) ?
 854              align_object_offset(nonstatic_oop_map_size) :
 855              nonstatic_oop_map_size) +
 856            (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
 857            (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
 858   }
 859   int size() const                    { return size(vtable_length(),
 860                                                itable_length(),
 861                                                nonstatic_oop_map_size(),
 862                                                is_interface(),
 863                                                is_anonymous());
 864   }
 865 #if INCLUDE_SERVICES
 866   virtual void collect_statistics(KlassSizeStats *sz) const;
 867 #endif
 868 
 869   static int vtable_start_offset()    { return header_size(); }
 870   static int vtable_length_offset()   { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
 871 
 872   intptr_t* start_of_vtable() const        { return ((intptr_t*)this) + vtable_start_offset(); }
 873   intptr_t* start_of_itable() const        { return start_of_vtable() + align_object_offset(vtable_length()); }
 874   int  itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
 875 
 876   intptr_t* end_of_itable() const          { return start_of_itable() + itable_length(); }
 877 
 878   address static_field_addr(int offset);
 879 
 880   OopMapBlock* start_of_nonstatic_oop_maps() const {
 881     return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
 882   }
 883 
 884   Klass** end_of_nonstatic_oop_maps() const {
 885     return (Klass**)(start_of_nonstatic_oop_maps() +
 886                      nonstatic_oop_map_count());
 887   }
 888 
 889   Klass** adr_implementor() const {
 890     if (is_interface()) {
 891       return (Klass**)end_of_nonstatic_oop_maps();
 892     } else {
 893       return NULL;
 894     }
 895   };
 896 
 897   Klass** adr_host_klass() const {
 898     if (is_anonymous()) {
 899       Klass** adr_impl = adr_implementor();
 900       if (adr_impl != NULL) {
 901         return adr_impl + 1;
 902       } else {
 903         return end_of_nonstatic_oop_maps();
 904       }
 905     } else {
 906       return NULL;
 907     }
 908   }
 909 
 910   // Use this to return the size of an instance in heap words:
 911   int size_helper() const {
 912     return layout_helper_to_size_helper(layout_helper());
 913   }
 914 
 915   // This bit is initialized in classFileParser.cpp.
 916   // It is false under any of the following conditions:
 917   //  - the class is abstract (including any interface)
 918   //  - the class has a finalizer (if !RegisterFinalizersAtInit)
 919   //  - the class size is larger than FastAllocateSizeLimit
 920   //  - the class is java/lang/Class, which cannot be allocated directly
 921   bool can_be_fastpath_allocated() const {
 922     return !layout_helper_needs_slow_path(layout_helper());
 923   }
 924 
 925   // Java vtable/itable
 926   klassVtable* vtable() const;        // return new klassVtable wrapper
 927   inline Method* method_at_vtable(int index);
 928   klassItable* itable() const;        // return new klassItable wrapper
 929   Method* method_at_itable(Klass* holder, int index, TRAPS);
 930 
 931 #if INCLUDE_JVMTI
 932   void adjust_default_methods(Method** old_methods, Method** new_methods,
 933                               int methods_length, bool* trace_name_printed);
 934 #endif // INCLUDE_JVMTI
 935 
 936   // Garbage collection
 937   void oop_follow_contents(oop obj);
 938   int  oop_adjust_pointers(oop obj);
 939 
 940   void clean_implementors_list(BoolObjectClosure* is_alive);
 941   void clean_method_data(BoolObjectClosure* is_alive);
 942   void clean_dependent_nmethods();
 943 
 944   // Explicit metaspace deallocation of fields
 945   // For RedefineClasses and class file parsing errors, we need to deallocate
 946   // instanceKlasses and the metadata they point to.
 947   void deallocate_contents(ClassLoaderData* loader_data);
 948   static void deallocate_methods(ClassLoaderData* loader_data,
 949                                  Array<Method*>* methods);
 950   void static deallocate_interfaces(ClassLoaderData* loader_data,
 951                                     Klass* super_klass,
 952                                     Array<Klass*>* local_interfaces,
 953                                     Array<Klass*>* transitive_interfaces);
 954 
 955   // The constant pool is on stack if any of the methods are executing or
 956   // referenced by handles.
 957   bool on_stack() const { return _constants->on_stack(); }
 958 
 959   // callbacks for actions during class unloading
 960   static void notify_unload_class(InstanceKlass* ik);
 961   static void release_C_heap_structures(InstanceKlass* ik);
 962 
 963   // Parallel Scavenge and Parallel Old
 964   PARALLEL_GC_DECLS
 965 
 966   // Naming
 967   const char* signature_name() const;
 968 
 969   // Iterators
 970   int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
 971     return oop_oop_iterate_v(obj, blk);
 972   }
 973 
 974   int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
 975     return oop_oop_iterate_v_m(obj, blk, mr);
 976   }
 977 
 978 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix)      \
 979   int  oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk);           \
 980   int  oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk,        \
 981                                       MemRegion mr);
 982 
 983   ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
 984   ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
 985 
 986 #if INCLUDE_ALL_GCS
 987 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
 988   int  oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
 989 
 990   ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
 991   ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
 992 #endif // INCLUDE_ALL_GCS
 993 
 994   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
 995 
 996 public:
 997   void set_in_error_state() {
 998     assert(DumpSharedSpaces, "only call this when dumping archive");
 999     _init_state = initialization_error;
1000   }
1001   bool check_sharing_error_state();
1002 
1003 private:
1004   // initialization state
1005 #ifdef ASSERT
1006   void set_init_state(ClassState state);
1007 #else
1008   void set_init_state(ClassState state) { _init_state = (u1)state; }
1009 #endif
1010   void set_rewritten()                  { _misc_flags |= _misc_rewritten; }
1011   void set_init_thread(Thread *thread)  { _init_thread = thread; }
1012 
1013   // The RedefineClasses() API can cause new method idnums to be needed
1014   // which will cause the caches to grow. Safety requires different
1015   // cache management logic if the caches can grow instead of just
1016   // going from NULL to non-NULL.
1017   bool idnum_can_increment() const      { return has_been_redefined(); }
1018   jmethodID* methods_jmethod_ids_acquire() const
1019          { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
1020   void release_set_methods_jmethod_ids(jmethodID* jmeths)
1021          { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
1022 
1023   // Lock during initialization
1024 public:
1025   // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1026   // Must be one per class and it has to be a VM internal object so java code
1027   // cannot lock it (like the mirror).
1028   // It has to be an object not a Mutex because it's held through java calls.
1029   oop init_lock() const;
1030 private:
1031   void fence_and_clear_init_lock();
1032 
1033   // Static methods that are used to implement member methods where an exposed this pointer
1034   // is needed due to possible GCs
1035   static bool link_class_impl                           (instanceKlassHandle this_k, bool throw_verifyerror, TRAPS);
1036   static bool verify_code                               (instanceKlassHandle this_k, bool throw_verifyerror, TRAPS);
1037   static void initialize_impl                           (instanceKlassHandle this_k, TRAPS);
1038   static void initialize_super_interfaces               (instanceKlassHandle this_k, TRAPS);
1039   static void eager_initialize_impl                     (instanceKlassHandle this_k);
1040   static void set_initialization_state_and_notify_impl  (instanceKlassHandle this_k, ClassState state, TRAPS);
1041   static void call_class_initializer_impl               (instanceKlassHandle this_k, TRAPS);
1042   static Klass* array_klass_impl                        (instanceKlassHandle this_k, bool or_null, int n, TRAPS);
1043   static void do_local_static_fields_impl               (instanceKlassHandle this_k, void f(fieldDescriptor* fd, Handle, TRAPS), Handle, TRAPS);
1044   /* jni_id_for_impl for jfieldID only */
1045   static JNIid* jni_id_for_impl                         (instanceKlassHandle this_k, int offset);
1046 
1047   // Returns the array class for the n'th dimension
1048   Klass* array_klass_impl(bool or_null, int n, TRAPS);
1049 
1050   // Returns the array class with this class as element type
1051   Klass* array_klass_impl(bool or_null, TRAPS);
1052 
1053   // find a local method (returns NULL if not found)
1054   Method* find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const;
1055   static Method* find_method_impl(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
1056 
1057   // Free CHeap allocated fields.
1058   void release_C_heap_structures();
1059 
1060   // RedefineClasses support
1061   void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1062   void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1063 public:
1064   // CDS support - remove and restore oops from metadata. Oops are not shared.
1065   virtual void remove_unshareable_info();
1066   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
1067 
1068   // jvm support
1069   jint compute_modifier_flags(TRAPS) const;
1070 
1071   // JSR-292 support
1072   MemberNameTable* member_names() { return _member_names; }
1073   void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1074   void add_member_name(int index, Handle member_name);
1075   oop  get_member_name(int index);
1076 
1077 public:
1078   // JVMTI support
1079   jint jvmti_class_status() const;
1080 
1081  public:
1082   // Printing
1083 #ifndef PRODUCT
1084   void print_on(outputStream* st) const;
1085 #endif
1086   void print_value_on(outputStream* st) const;
1087 
1088   void oop_print_value_on(oop obj, outputStream* st);
1089 
1090 #ifndef PRODUCT
1091   void oop_print_on      (oop obj, outputStream* st);
1092 
1093   void print_dependent_nmethods(bool verbose = false);
1094   bool is_dependent_nmethod(nmethod* nm);
1095 #endif
1096 
1097   const char* internal_name() const;
1098 
1099   // Verification
1100   void verify_on(outputStream* st);
1101 
1102   void oop_verify_on(oop obj, outputStream* st);
1103 };
1104 
1105 inline Method* InstanceKlass::method_at_vtable(int index)  {
1106 #ifndef PRODUCT
1107   assert(index >= 0, "valid vtable index");
1108   if (DebugVtables) {
1109     verify_vtable_index(index);
1110   }
1111 #endif
1112   vtableEntry* ve = (vtableEntry*)start_of_vtable();
1113   return ve[index].method();
1114 }
1115 
1116 // for adding methods
1117 // UNSET_IDNUM return means no more ids available
1118 inline u2 InstanceKlass::next_method_idnum() {
1119   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1120     return ConstMethod::UNSET_IDNUM; // no more ids available
1121   } else {
1122     return _idnum_allocated_count++;
1123   }
1124 }
1125 
1126 
1127 /* JNIid class for jfieldIDs only */
1128 class JNIid: public CHeapObj<mtClass> {
1129   friend class VMStructs;
1130  private:
1131   Klass*             _holder;
1132   JNIid*             _next;
1133   int                _offset;
1134 #ifdef ASSERT
1135   bool               _is_static_field_id;
1136 #endif
1137 
1138  public:
1139   // Accessors
1140   Klass* holder() const           { return _holder; }
1141   int offset() const              { return _offset; }
1142   JNIid* next()                   { return _next; }
1143   // Constructor
1144   JNIid(Klass* holder, int offset, JNIid* next);
1145   // Identifier lookup
1146   JNIid* find(int offset);
1147 
1148   bool find_local_field(fieldDescriptor* fd) {
1149     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1150   }
1151 
1152   static void deallocate(JNIid* id);
1153   // Debugging
1154 #ifdef ASSERT
1155   bool is_static_field_id() const { return _is_static_field_id; }
1156   void set_is_static_field_id()   { _is_static_field_id = true; }
1157 #endif
1158   void verify(Klass* holder);
1159 };
1160 
1161 
1162 //
1163 // nmethodBucket is used to record dependent nmethods for
1164 // deoptimization.  nmethod dependencies are actually <klass, method>
1165 // pairs but we really only care about the klass part for purposes of
1166 // finding nmethods which might need to be deoptimized.  Instead of
1167 // recording the method, a count of how many times a particular nmethod
1168 // was recorded is kept.  This ensures that any recording errors are
1169 // noticed since an nmethod should be removed as many times are it's
1170 // added.
1171 //
1172 class nmethodBucket: public CHeapObj<mtClass> {
1173   friend class VMStructs;
1174  private:
1175   nmethod*       _nmethod;
1176   int            _count;
1177   nmethodBucket* _next;
1178 
1179  public:
1180   nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1181     _nmethod = nmethod;
1182     _next = next;
1183     _count = 1;
1184   }
1185   int count()                             { return _count; }
1186   int increment()                         { _count += 1; return _count; }
1187   int decrement();
1188   nmethodBucket* next()                   { return _next; }
1189   void set_next(nmethodBucket* b)         { _next = b; }
1190   nmethod* get_nmethod()                  { return _nmethod; }
1191 };
1192 
1193 // An iterator that's used to access the inner classes indices in the
1194 // InstanceKlass::_inner_classes array.
1195 class InnerClassesIterator : public StackObj {
1196  private:
1197   Array<jushort>* _inner_classes;
1198   int _length;
1199   int _idx;
1200  public:
1201 
1202   InnerClassesIterator(instanceKlassHandle k) {
1203     _inner_classes = k->inner_classes();
1204     if (k->inner_classes() != NULL) {
1205       _length = _inner_classes->length();
1206       // The inner class array's length should be the multiple of
1207       // inner_class_next_offset if it only contains the InnerClasses
1208       // attribute data, or it should be
1209       // n*inner_class_next_offset+enclosing_method_attribute_size
1210       // if it also contains the EnclosingMethod data.
1211       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1212               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1213              "just checking");
1214       // Remove the enclosing_method portion if exists.
1215       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1216         _length -= InstanceKlass::enclosing_method_attribute_size;
1217       }
1218     } else {
1219       _length = 0;
1220     }
1221     _idx = 0;
1222   }
1223 
1224   int length() const {
1225     return _length;
1226   }
1227 
1228   void next() {
1229     _idx += InstanceKlass::inner_class_next_offset;
1230   }
1231 
1232   bool done() const {
1233     return (_idx >= _length);
1234   }
1235 
1236   u2 inner_class_info_index() const {
1237     return _inner_classes->at(
1238                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1239   }
1240 
1241   void set_inner_class_info_index(u2 index) {
1242     _inner_classes->at_put(
1243                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1244   }
1245 
1246   u2 outer_class_info_index() const {
1247     return _inner_classes->at(
1248                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1249   }
1250 
1251   void set_outer_class_info_index(u2 index) {
1252     _inner_classes->at_put(
1253                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1254   }
1255 
1256   u2 inner_name_index() const {
1257     return _inner_classes->at(
1258                _idx + InstanceKlass::inner_class_inner_name_offset);
1259   }
1260 
1261   void set_inner_name_index(u2 index) {
1262     _inner_classes->at_put(
1263                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1264   }
1265 
1266   u2 inner_access_flags() const {
1267     return _inner_classes->at(
1268                _idx + InstanceKlass::inner_class_access_flags_offset);
1269   }
1270 };
1271 
1272 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP