1 /*
   2  * Copyright 1997-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 // An instanceKlass is the VM level representation of a Java class.
  26 // It contains all information needed for at class at execution runtime.
  27 
  28 //  instanceKlass layout:
  29 //    [header                     ] klassOop
  30 //    [klass pointer              ] klassOop
  31 //    [C++ vtbl pointer           ] Klass
  32 //    [subtype cache              ] Klass
  33 //    [instance size              ] Klass
  34 //    [java mirror                ] Klass
  35 //    [super                      ] Klass
  36 //    [access_flags               ] Klass
  37 //    [name                       ] Klass
  38 //    [first subklass             ] Klass
  39 //    [next sibling               ] Klass
  40 //    [array klasses              ]
  41 //    [methods                    ]
  42 //    [local interfaces           ]
  43 //    [transitive interfaces      ]
  44 //    [number of implementors     ]
  45 //    [implementors               ] klassOop[2]
  46 //    [fields                     ]
  47 //    [constants                  ]
  48 //    [class loader               ]
  49 //    [protection domain          ]
  50 //    [signers                    ]
  51 //    [source file name           ]
  52 //    [inner classes              ]
  53 //    [static field size          ]
  54 //    [nonstatic field size       ]
  55 //    [static oop fields size     ]
  56 //    [nonstatic oop maps size    ]
  57 //    [has finalize method        ]
  58 //    [deoptimization mark bit    ]
  59 //    [initialization state       ]
  60 //    [initializing thread        ]
  61 //    [Java vtable length         ]
  62 //    [oop map cache (stack maps) ]
  63 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  64 //    [EMBEDDED static oop fields       ] size in words = static_oop_fields_size
  65 //    [         static non-oop fields   ] size in words = static_field_size - static_oop_fields_size
  66 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  67 //
  68 //    The embedded nonstatic oop-map blocks are short pairs (offset, length) indicating
  69 //    where oops are located in instances of this klass.
  70 
  71 
  72 // forward declaration for class -- see below for definition
  73 class SuperTypeClosure;
  74 class OopMapBlock;
  75 class JNIid;
  76 class jniIdMapBase;
  77 class BreakpointInfo;
  78 class fieldDescriptor;
  79 class DepChange;
  80 class nmethodBucket;
  81 class PreviousVersionNode;
  82 class JvmtiCachedClassFieldMap;
  83 
  84 // This is used in iterators below.
  85 class FieldClosure: public StackObj {
  86 public:
  87   virtual void do_field(fieldDescriptor* fd) = 0;
  88 };
  89 
  90 #ifndef PRODUCT
  91 // Print fields.
  92 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
  93 class FieldPrinter: public FieldClosure {
  94    oop _obj;
  95    outputStream* _st;
  96  public:
  97    FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
  98    void do_field(fieldDescriptor* fd);
  99 };
 100 #endif  // !PRODUCT
 101 
 102 class instanceKlass: public Klass {
 103   friend class VMStructs;
 104  public:
 105   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 106   // of the class loading & initialization procedure, and the use of the states.
 107   enum ClassState {
 108     unparsable_by_gc = 0,               // object is not yet parsable by gc. Value of _init_state at object allocation.
 109     allocated,                          // allocated (but not yet linked)
 110     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 111     linked,                             // successfully linked/verified (but not initialized yet)
 112     being_initialized,                  // currently running class initializer
 113     fully_initialized,                  // initialized (successfull final state)
 114     initialization_error                // error happened during initialization
 115   };
 116 
 117  public:
 118   oop* oop_block_beg() const { return adr_array_klasses(); }
 119   oop* oop_block_end() const { return adr_methods_default_annotations() + 1; }
 120 
 121   enum {
 122     implementors_limit = 2              // how many implems can we track?
 123   };
 124 
 125  protected:
 126   //
 127   // The oop block.  See comment in klass.hpp before making changes.
 128   //
 129 
 130   // Array classes holding elements of this class.
 131   klassOop        _array_klasses;
 132   // Method array.
 133   objArrayOop     _methods;
 134   // Int array containing the original order of method in the class file (for
 135   // JVMTI).
 136   typeArrayOop    _method_ordering;
 137   // Interface (klassOops) this class declares locally to implement.
 138   objArrayOop     _local_interfaces;
 139   // Interface (klassOops) this class implements transitively.
 140   objArrayOop     _transitive_interfaces;
 141   // Instance and static variable information, 5-tuples of shorts [access, name
 142   // index, sig index, initval index, offset].
 143   typeArrayOop    _fields;
 144   // Constant pool for this class.
 145   constantPoolOop _constants;
 146   // Class loader used to load this class, NULL if VM loader used.
 147   oop             _class_loader;
 148   // Protection domain.
 149   oop             _protection_domain;
 150   // Host class, which shares access with this class
 151   klassOop        _host_klass;
 152   // Class signers.
 153   objArrayOop     _signers;
 154   // Name of source file containing this klass, NULL if not specified.
 155   symbolOop       _source_file_name;
 156   // the source debug extension for this klass, NULL if not specified.
 157   symbolOop       _source_debug_extension;
 158   // inner_classes attribute.
 159   typeArrayOop    _inner_classes;
 160   // Implementors of this interface (not valid if it overflows)
 161   klassOop        _implementors[implementors_limit];
 162   // Generic signature, or null if none.
 163   symbolOop       _generic_signature;
 164   // Annotations for this class, or null if none.
 165   typeArrayOop    _class_annotations;
 166   // Annotation objects (byte arrays) for fields, or null if no annotations.
 167   // Indices correspond to entries (not indices) in fields array.
 168   objArrayOop     _fields_annotations;
 169   // Annotation objects (byte arrays) for methods, or null if no annotations.
 170   // Index is the idnum, which is initially the same as the methods array index.
 171   objArrayOop     _methods_annotations;
 172   // Annotation objects (byte arrays) for methods' parameters, or null if no
 173   // such annotations.
 174   // Index is the idnum, which is initially the same as the methods array index.
 175   objArrayOop     _methods_parameter_annotations;
 176   // Annotation objects (byte arrays) for methods' default values, or null if no
 177   // such annotations.
 178   // Index is the idnum, which is initially the same as the methods array index.
 179   objArrayOop     _methods_default_annotations;
 180 
 181   //
 182   // End of the oop block.
 183   //
 184 
 185   int             _nonstatic_field_size; // number of non-static fields in this klass (including inherited fields)
 186   int             _static_field_size;    // number of static fields (oop and non-oop) in this klass
 187   int             _static_oop_field_size;// number of static oop fields in this klass
 188   int             _nonstatic_oop_map_size;// number of nonstatic oop-map blocks allocated at end of this klass
 189   bool            _is_marked_dependent;  // used for marking during flushing and deoptimization
 190   bool            _rewritten;            // methods rewritten.
 191   u2              _minor_version;        // minor version number of class file
 192   u2              _major_version;        // major version number of class file
 193   ClassState      _init_state;           // state of class
 194   Thread*         _init_thread;          // Pointer to current thread doing initialization (to handle recusive initialization)
 195   int             _vtable_len;           // length of Java vtable (in words)
 196   int             _itable_len;           // length of Java itable (in words)
 197   ReferenceType   _reference_type;       // reference type
 198   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 199   JNIid*          _jni_ids;              // First JNI identifier for static fields in this class
 200   jmethodID*      _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or NULL if none
 201   int*            _methods_cached_itable_indices;  // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
 202   nmethodBucket*  _dependencies;         // list of dependent nmethods
 203   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 204   BreakpointInfo* _breakpoints;          // bpt lists, managed by methodOop
 205   int             _nof_implementors;     // No of implementors of this interface (zero if not an interface)
 206   // Array of interesting part(s) of the previous version(s) of this
 207   // instanceKlass. See PreviousVersionWalker below.
 208   GrowableArray<PreviousVersionNode *>* _previous_versions;
 209   u2              _enclosing_method_class_index;  // Constant pool index for class of enclosing method, or 0 if none
 210   u2              _enclosing_method_method_index; // Constant pool index for name and type of enclosing method, or 0 if none
 211   // JVMTI fields can be moved to their own structure - see 6315920
 212   unsigned char * _cached_class_file_bytes;       // JVMTI: cached class file, before retransformable agent modified it in CFLH
 213   jint            _cached_class_file_len;         // JVMTI: length of above
 214   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 215   volatile u2     _idnum_allocated_count;         // JNI/JVMTI: increments with the addition of methods, old ids don't change
 216 
 217   // embedded Java vtable follows here
 218   // embedded Java itables follows here
 219   // embedded static fields follows here
 220   // embedded nonstatic oop-map blocks follows here
 221 
 222   friend class instanceKlassKlass;
 223   friend class SystemDictionary;
 224 
 225  public:
 226   // field sizes
 227   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 228   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 229 
 230   int static_field_size() const            { return _static_field_size; }
 231   void set_static_field_size(int size)     { _static_field_size = size; }
 232 
 233   int static_oop_field_size() const        { return _static_oop_field_size; }
 234   void set_static_oop_field_size(int size) { _static_oop_field_size = size; }
 235 
 236   // Java vtable
 237   int  vtable_length() const               { return _vtable_len; }
 238   void set_vtable_length(int len)          { _vtable_len = len; }
 239 
 240   // Java itable
 241   int  itable_length() const               { return _itable_len; }
 242   void set_itable_length(int len)          { _itable_len = len; }
 243 
 244   // array klasses
 245   klassOop array_klasses() const           { return _array_klasses; }
 246   void set_array_klasses(klassOop k)       { oop_store_without_check((oop*) &_array_klasses, (oop) k); }
 247 
 248   // methods
 249   objArrayOop methods() const              { return _methods; }
 250   void set_methods(objArrayOop a)          { oop_store_without_check((oop*) &_methods, (oop) a); }
 251   methodOop method_with_idnum(int idnum);
 252 
 253   // method ordering
 254   typeArrayOop method_ordering() const     { return _method_ordering; }
 255   void set_method_ordering(typeArrayOop m) { oop_store_without_check((oop*) &_method_ordering, (oop) m); }
 256 
 257   // interfaces
 258   objArrayOop local_interfaces() const          { return _local_interfaces; }
 259   void set_local_interfaces(objArrayOop a)      { oop_store_without_check((oop*) &_local_interfaces, (oop) a); }
 260   objArrayOop transitive_interfaces() const     { return _transitive_interfaces; }
 261   void set_transitive_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_transitive_interfaces, (oop) a); }
 262 
 263   // fields
 264   // Field info extracted from the class file and stored
 265   // as an array of 7 shorts
 266   enum FieldOffset {
 267     access_flags_offset    = 0,
 268     name_index_offset      = 1,
 269     signature_index_offset = 2,
 270     initval_index_offset   = 3,
 271     low_offset             = 4,
 272     high_offset            = 5,
 273     generic_signature_offset = 6,
 274     next_offset            = 7
 275   };
 276 
 277   typeArrayOop fields() const              { return _fields; }
 278   int offset_from_fields( int index ) const {
 279     return build_int_from_shorts( fields()->ushort_at(index + low_offset),
 280                                   fields()->ushort_at(index + high_offset) );
 281   }
 282 
 283   void set_fields(typeArrayOop f)          { oop_store_without_check((oop*) &_fields, (oop) f); }
 284 
 285   // inner classes
 286   typeArrayOop inner_classes() const       { return _inner_classes; }
 287   void set_inner_classes(typeArrayOop f)   { oop_store_without_check((oop*) &_inner_classes, (oop) f); }
 288 
 289   enum InnerClassAttributeOffset {
 290     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 291     inner_class_inner_class_info_offset = 0,
 292     inner_class_outer_class_info_offset = 1,
 293     inner_class_inner_name_offset = 2,
 294     inner_class_access_flags_offset = 3,
 295     inner_class_next_offset = 4
 296   };
 297 
 298   // package
 299   bool is_same_class_package(klassOop class2);
 300   bool is_same_class_package(oop classloader2, symbolOop classname2);
 301   static bool is_same_class_package(oop class_loader1, symbolOop class_name1, oop class_loader2, symbolOop class_name2);
 302 
 303   // initialization state
 304   bool is_loaded() const                   { return _init_state >= loaded; }
 305   bool is_linked() const                   { return _init_state >= linked; }
 306   bool is_initialized() const              { return _init_state == fully_initialized; }
 307   bool is_not_initialized() const          { return _init_state <  being_initialized; }
 308   bool is_being_initialized() const        { return _init_state == being_initialized; }
 309   bool is_in_error_state() const           { return _init_state == initialization_error; }
 310   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 311   int  get_init_state()                    { return _init_state; } // Useful for debugging
 312   bool is_rewritten() const                { return _rewritten; }
 313 
 314   // marking
 315   bool is_marked_dependent() const         { return _is_marked_dependent; }
 316   void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
 317 
 318   // initialization (virtuals from Klass)
 319   bool should_be_initialized() const;  // means that initialize should be called
 320   void initialize(TRAPS);
 321   void link_class(TRAPS);
 322   bool link_class_or_fail(TRAPS); // returns false on failure
 323   void unlink_class();
 324   void rewrite_class(TRAPS);
 325   methodOop class_initializer();
 326 
 327   // set the class to initialized if no static initializer is present
 328   void eager_initialize(Thread *thread);
 329 
 330   // reference type
 331   ReferenceType reference_type() const     { return _reference_type; }
 332   void set_reference_type(ReferenceType t) { _reference_type = t; }
 333 
 334   // find local field, returns true if found
 335   bool find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
 336   // find field in direct superinterfaces, returns the interface in which the field is defined
 337   klassOop find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
 338   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 339   klassOop find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const;
 340   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 341   klassOop find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const;
 342 
 343   // find a non-static or static field given its offset within the class.
 344   bool contains_field_offset(int offset) {
 345       return ((offset/wordSize) >= instanceOopDesc::header_size() &&
 346              (offset/wordSize)-instanceOopDesc::header_size() < nonstatic_field_size());
 347   }
 348 
 349   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 350   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 351 
 352   // find a local method (returns NULL if not found)
 353   methodOop find_method(symbolOop name, symbolOop signature) const;
 354   static methodOop find_method(objArrayOop methods, symbolOop name, symbolOop signature);
 355 
 356   // lookup operation (returns NULL if not found)
 357   methodOop uncached_lookup_method(symbolOop name, symbolOop signature) const;
 358 
 359   // lookup a method in all the interfaces that this class implements
 360   // (returns NULL if not found)
 361   methodOop lookup_method_in_all_interfaces(symbolOop name, symbolOop signature) const;
 362 
 363   // constant pool
 364   constantPoolOop constants() const        { return _constants; }
 365   void set_constants(constantPoolOop c)    { oop_store_without_check((oop*) &_constants, (oop) c); }
 366 
 367   // class loader
 368   oop class_loader() const                 { return _class_loader; }
 369   void set_class_loader(oop l)             { oop_store((oop*) &_class_loader, l); }
 370 
 371   // protection domain
 372   oop protection_domain()                  { return _protection_domain; }
 373   void set_protection_domain(oop pd)       { oop_store((oop*) &_protection_domain, pd); }
 374 
 375   // host class
 376   oop host_klass() const                   { return _host_klass; }
 377   void set_host_klass(oop host)            { oop_store((oop*) &_host_klass, host); }
 378   bool is_anonymous() const                { return _host_klass != NULL; }
 379 
 380   // signers
 381   objArrayOop signers() const              { return _signers; }
 382   void set_signers(objArrayOop s)          { oop_store((oop*) &_signers, oop(s)); }
 383 
 384   // source file name
 385   symbolOop source_file_name() const       { return _source_file_name; }
 386   void set_source_file_name(symbolOop n)   { oop_store_without_check((oop*) &_source_file_name, (oop) n); }
 387 
 388   // minor and major version numbers of class file
 389   u2 minor_version() const                 { return _minor_version; }
 390   void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
 391   u2 major_version() const                 { return _major_version; }
 392   void set_major_version(u2 major_version) { _major_version = major_version; }
 393 
 394   // source debug extension
 395   symbolOop source_debug_extension() const    { return _source_debug_extension; }
 396   void set_source_debug_extension(symbolOop n){ oop_store_without_check((oop*) &_source_debug_extension, (oop) n); }
 397 
 398   // nonstatic oop-map blocks
 399   int nonstatic_oop_map_size() const        { return _nonstatic_oop_map_size; }
 400   void set_nonstatic_oop_map_size(int size) { _nonstatic_oop_map_size = size; }
 401 
 402   // RedefineClasses() support for previous versions:
 403   void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
 404          int emcp_method_count);
 405   bool has_previous_version() const;
 406   void init_previous_versions() {
 407     _previous_versions = NULL;
 408   }
 409   GrowableArray<PreviousVersionNode *>* previous_versions() const {
 410     return _previous_versions;
 411   }
 412 
 413   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 414   void set_cached_class_file(unsigned char *class_file_bytes,
 415                              jint class_file_len)     { _cached_class_file_len = class_file_len;
 416                                                         _cached_class_file_bytes = class_file_bytes; }
 417   jint get_cached_class_file_len()                    { return _cached_class_file_len; }
 418   unsigned char * get_cached_class_file_bytes()       { return _cached_class_file_bytes; }
 419 
 420   // JVMTI: Support for caching of field indices, types, and offsets
 421   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 422     _jvmti_cached_class_field_map = descriptor;
 423   }
 424   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 425     return _jvmti_cached_class_field_map;
 426   }
 427 
 428   // for adding methods, constMethodOopDesc::UNSET_IDNUM means no more ids available
 429   inline u2 next_method_idnum();
 430   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 431 
 432   // generics support
 433   symbolOop generic_signature() const                 { return _generic_signature; }
 434   void set_generic_signature(symbolOop sig)           { oop_store_without_check((oop*)&_generic_signature, (oop)sig); }
 435   u2 enclosing_method_class_index() const             { return _enclosing_method_class_index; }
 436   u2 enclosing_method_method_index() const            { return _enclosing_method_method_index; }
 437   void set_enclosing_method_indices(u2 class_index,
 438                                     u2 method_index)  { _enclosing_method_class_index  = class_index;
 439                                                         _enclosing_method_method_index = method_index; }
 440 
 441   // jmethodID support
 442   static jmethodID jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h);
 443   jmethodID jmethod_id_or_null(methodOop method);
 444 
 445   // cached itable index support
 446   void set_cached_itable_index(size_t idnum, int index);
 447   int cached_itable_index(size_t idnum);
 448 
 449   // annotations support
 450   typeArrayOop class_annotations() const              { return _class_annotations; }
 451   objArrayOop fields_annotations() const              { return _fields_annotations; }
 452   objArrayOop methods_annotations() const             { return _methods_annotations; }
 453   objArrayOop methods_parameter_annotations() const   { return _methods_parameter_annotations; }
 454   objArrayOop methods_default_annotations() const     { return _methods_default_annotations; }
 455   void set_class_annotations(typeArrayOop md)            { oop_store_without_check((oop*)&_class_annotations, (oop)md); }
 456   void set_fields_annotations(objArrayOop md)            { set_annotations(md, &_fields_annotations); }
 457   void set_methods_annotations(objArrayOop md)           { set_annotations(md, &_methods_annotations); }
 458   void set_methods_parameter_annotations(objArrayOop md) { set_annotations(md, &_methods_parameter_annotations); }
 459   void set_methods_default_annotations(objArrayOop md)   { set_annotations(md, &_methods_default_annotations); }
 460   typeArrayOop get_method_annotations_of(int idnum)
 461                                                 { return get_method_annotations_from(idnum, _methods_annotations); }
 462   typeArrayOop get_method_parameter_annotations_of(int idnum)
 463                                                 { return get_method_annotations_from(idnum, _methods_parameter_annotations); }
 464   typeArrayOop get_method_default_annotations_of(int idnum)
 465                                                 { return get_method_annotations_from(idnum, _methods_default_annotations); }
 466   void set_method_annotations_of(int idnum, typeArrayOop anno)
 467                                                 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
 468   void set_method_parameter_annotations_of(int idnum, typeArrayOop anno)
 469                                                 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
 470   void set_method_default_annotations_of(int idnum, typeArrayOop anno)
 471                                                 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
 472 
 473   // allocation
 474   DEFINE_ALLOCATE_PERMANENT(instanceKlass);
 475   instanceOop allocate_instance(TRAPS);
 476   instanceOop allocate_permanent_instance(TRAPS);
 477 
 478   // additional member function to return a handle
 479   instanceHandle allocate_instance_handle(TRAPS)      { return instanceHandle(THREAD, allocate_instance(THREAD)); }
 480 
 481   objArrayOop allocate_objArray(int n, int length, TRAPS);
 482   // Helper function
 483   static instanceOop register_finalizer(instanceOop i, TRAPS);
 484 
 485   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 486   // if not, throw either an Error or an Exception.
 487   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
 488 
 489   // initialization
 490   void call_class_initializer(TRAPS);
 491   void set_initialization_state_and_notify(ClassState state, TRAPS);
 492 
 493   // OopMapCache support
 494   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 495   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 496   void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
 497 
 498   // JNI identifier support (for static fields - for jni performance)
 499   JNIid* jni_ids()                               { return _jni_ids; }
 500   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 501   JNIid* jni_id_for(int offset);
 502 
 503   // maintenance of deoptimization dependencies
 504   int mark_dependent_nmethods(DepChange& changes);
 505   void add_dependent_nmethod(nmethod* nm);
 506   void remove_dependent_nmethod(nmethod* nm);
 507 
 508   // On-stack replacement support
 509   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 510   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 511   void add_osr_nmethod(nmethod* n);
 512   void remove_osr_nmethod(nmethod* n);
 513   nmethod* lookup_osr_nmethod(const methodOop m, int bci) const;
 514 
 515   // Breakpoint support (see methods on methodOop for details)
 516   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 517   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 518 
 519   // support for stub routines
 520   static int init_state_offset_in_bytes()    { return offset_of(instanceKlass, _init_state); }
 521   static int init_thread_offset_in_bytes()   { return offset_of(instanceKlass, _init_thread); }
 522 
 523   // subclass/subinterface checks
 524   bool implements_interface(klassOop k) const;
 525 
 526   // Access to implementors of an interface. We only store the count
 527   // of implementors, and in case, there are only a few
 528   // implementors, we store them in a short list.
 529   // This accessor returns NULL if we walk off the end of the list.
 530   klassOop implementor(int i) const {
 531     return (i < implementors_limit)? _implementors[i]: (klassOop) NULL;
 532   }
 533   int  nof_implementors() const       { return _nof_implementors; }
 534   void add_implementor(klassOop k);  // k is a new class that implements this interface
 535   void init_implementor();           // initialize
 536 
 537   // link this class into the implementors list of every interface it implements
 538   void process_interfaces(Thread *thread);
 539 
 540   // virtual operations from Klass
 541   bool is_leaf_class() const               { return _subklass == NULL; }
 542   objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS);
 543   bool compute_is_subtype_of(klassOop k);
 544   bool can_be_primary_super_slow() const;
 545   klassOop java_super() const              { return super(); }
 546   int oop_size(oop obj)  const             { return size_helper(); }
 547   int klass_oop_size() const               { return object_size(); }
 548   bool oop_is_instance_slow() const        { return true; }
 549 
 550   // Iterators
 551   void do_local_static_fields(FieldClosure* cl);
 552   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
 553   void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
 554 
 555   void methods_do(void f(methodOop method));
 556   void array_klasses_do(void f(klassOop k));
 557   void with_array_klasses_do(void f(klassOop k));
 558   bool super_types_do(SuperTypeClosure* blk);
 559 
 560   // Casting from klassOop
 561   static instanceKlass* cast(klassOop k) {
 562     Klass* kp = k->klass_part();
 563     assert(kp->null_vtbl() || kp->oop_is_instance_slow(), "cast to instanceKlass");
 564     return (instanceKlass*) kp;
 565   }
 566 
 567   // Sizing (in words)
 568   static int header_size()            { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); }
 569   int object_size() const             { return object_size(align_object_offset(vtable_length()) + align_object_offset(itable_length()) + static_field_size() + nonstatic_oop_map_size()); }
 570   static int vtable_start_offset()    { return header_size(); }
 571   static int vtable_length_offset()   { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; }
 572   static int object_size(int extra)   { return align_object_size(header_size() + extra); }
 573 
 574   intptr_t* start_of_vtable() const        { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); }
 575   intptr_t* start_of_itable() const        { return start_of_vtable() + align_object_offset(vtable_length()); }
 576   int  itable_offset_in_words() const { return start_of_itable() - (intptr_t*)as_klassOop(); }
 577 
 578   oop* start_of_static_fields() const { return (oop*)(start_of_itable() + align_object_offset(itable_length())); }
 579   intptr_t* end_of_itable() const          { return start_of_itable() + itable_length(); }
 580   oop* end_of_static_fields() const   { return start_of_static_fields() + static_field_size(); }
 581   int offset_of_static_fields() const { return (intptr_t)start_of_static_fields() - (intptr_t)as_klassOop(); }
 582 
 583   OopMapBlock* start_of_nonstatic_oop_maps() const { return (OopMapBlock*) (start_of_static_fields() + static_field_size()); }
 584 
 585   // Allocation profiling support
 586   juint alloc_size() const            { return _alloc_count * size_helper(); }
 587   void set_alloc_size(juint n)        {}
 588 
 589   // Use this to return the size of an instance in heap words:
 590   int size_helper() const {
 591     return layout_helper_to_size_helper(layout_helper());
 592   }
 593 
 594   // This bit is initialized in classFileParser.cpp.
 595   // It is false under any of the following conditions:
 596   //  - the class is abstract (including any interface)
 597   //  - the class has a finalizer (if !RegisterFinalizersAtInit)
 598   //  - the class size is larger than FastAllocateSizeLimit
 599   //  - the class is java/lang/Class, which cannot be allocated directly
 600   bool can_be_fastpath_allocated() const {
 601     return !layout_helper_needs_slow_path(layout_helper());
 602   }
 603 
 604   // Java vtable/itable
 605   klassVtable* vtable() const;        // return new klassVtable wrapper
 606   inline methodOop method_at_vtable(int index);
 607   klassItable* itable() const;        // return new klassItable wrapper
 608   methodOop method_at_itable(klassOop holder, int index, TRAPS);
 609 
 610   // Garbage collection
 611   void oop_follow_contents(oop obj);
 612   void follow_static_fields();
 613   void adjust_static_fields();
 614   int  oop_adjust_pointers(oop obj);
 615   bool object_is_parsable() const { return _init_state != unparsable_by_gc; }
 616        // Value of _init_state must be zero (unparsable_by_gc) when klass field is set.
 617 
 618   void follow_weak_klass_links(
 619     BoolObjectClosure* is_alive, OopClosure* keep_alive);
 620   void release_C_heap_structures();
 621 
 622   // Parallel Scavenge and Parallel Old
 623   PARALLEL_GC_DECLS
 624 
 625 #ifndef SERIALGC
 626   // Parallel Scavenge
 627   void copy_static_fields(PSPromotionManager* pm);
 628   void push_static_fields(PSPromotionManager* pm);
 629 
 630   // Parallel Old
 631   void follow_static_fields(ParCompactionManager* cm);
 632   void copy_static_fields(ParCompactionManager* cm);
 633   void update_static_fields();
 634   void update_static_fields(HeapWord* beg_addr, HeapWord* end_addr);
 635 #endif // SERIALGC
 636 
 637   // Naming
 638   char* signature_name() const;
 639 
 640   // Iterators
 641   int oop_oop_iterate(oop obj, OopClosure* blk) {
 642     return oop_oop_iterate_v(obj, blk);
 643   }
 644 
 645   int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
 646     return oop_oop_iterate_v_m(obj, blk, mr);
 647   }
 648 
 649 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix)   \
 650   int  oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk);        \
 651   int  oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk,     \
 652                                       MemRegion mr);
 653 
 654   ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
 655   ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DECL)
 656 
 657   void iterate_static_fields(OopClosure* closure);
 658   void iterate_static_fields(OopClosure* closure, MemRegion mr);
 659 
 660 private:
 661   // initialization state
 662 #ifdef ASSERT
 663   void set_init_state(ClassState state);
 664 #else
 665   void set_init_state(ClassState state) { _init_state = state; }
 666 #endif
 667   void set_rewritten()                  { _rewritten = true; }
 668   void set_init_thread(Thread *thread)  { _init_thread = thread; }
 669 
 670   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
 671   jmethodID* methods_jmethod_ids_acquire() const
 672          { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
 673   void release_set_methods_jmethod_ids(jmethodID* jmeths)
 674          { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
 675 
 676   int* methods_cached_itable_indices_acquire() const
 677          { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
 678   void release_set_methods_cached_itable_indices(int* indices)
 679          { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
 680 
 681   inline typeArrayOop get_method_annotations_from(int idnum, objArrayOop annos);
 682   void set_annotations(objArrayOop md, objArrayOop* md_p)  { oop_store_without_check((oop*)md_p, (oop)md); }
 683   void set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p);
 684 
 685   // Offsets for memory management
 686   oop* adr_array_klasses() const     { return (oop*)&this->_array_klasses;}
 687   oop* adr_methods() const           { return (oop*)&this->_methods;}
 688   oop* adr_method_ordering() const   { return (oop*)&this->_method_ordering;}
 689   oop* adr_local_interfaces() const  { return (oop*)&this->_local_interfaces;}
 690   oop* adr_transitive_interfaces() const  { return (oop*)&this->_transitive_interfaces;}
 691   oop* adr_fields() const            { return (oop*)&this->_fields;}
 692   oop* adr_constants() const         { return (oop*)&this->_constants;}
 693   oop* adr_class_loader() const      { return (oop*)&this->_class_loader;}
 694   oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
 695   oop* adr_host_klass() const        { return (oop*)&this->_host_klass;}
 696   oop* adr_signers() const           { return (oop*)&this->_signers;}
 697   oop* adr_source_file_name() const  { return (oop*)&this->_source_file_name;}
 698   oop* adr_source_debug_extension() const { return (oop*)&this->_source_debug_extension;}
 699   oop* adr_inner_classes() const     { return (oop*)&this->_inner_classes;}
 700   oop* adr_implementors() const      { return (oop*)&this->_implementors[0];}
 701   oop* adr_generic_signature() const { return (oop*)&this->_generic_signature;}
 702   oop* adr_methods_jmethod_ids() const             { return (oop*)&this->_methods_jmethod_ids;}
 703   oop* adr_methods_cached_itable_indices() const   { return (oop*)&this->_methods_cached_itable_indices;}
 704   oop* adr_class_annotations() const   { return (oop*)&this->_class_annotations;}
 705   oop* adr_fields_annotations() const  { return (oop*)&this->_fields_annotations;}
 706   oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;}
 707   oop* adr_methods_parameter_annotations() const { return (oop*)&this->_methods_parameter_annotations;}
 708   oop* adr_methods_default_annotations() const { return (oop*)&this->_methods_default_annotations;}
 709 
 710   // Static methods that are used to implement member methods where an exposed this pointer
 711   // is needed due to possible GCs
 712   static bool link_class_impl                           (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
 713   static bool verify_code                               (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
 714   static void initialize_impl                           (instanceKlassHandle this_oop, TRAPS);
 715   static void eager_initialize_impl                     (instanceKlassHandle this_oop);
 716   static void set_initialization_state_and_notify_impl  (instanceKlassHandle this_oop, ClassState state, TRAPS);
 717   static void call_class_initializer_impl               (instanceKlassHandle this_oop, TRAPS);
 718   static klassOop array_klass_impl                      (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
 719   static void do_local_static_fields_impl               (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
 720   /* jni_id_for_impl for jfieldID only */
 721   static JNIid* jni_id_for_impl                         (instanceKlassHandle this_oop, int offset);
 722 
 723   // Returns the array class for the n'th dimension
 724   klassOop array_klass_impl(bool or_null, int n, TRAPS);
 725 
 726   // Returns the array class with this class as element type
 727   klassOop array_klass_impl(bool or_null, TRAPS);
 728 
 729 public:
 730   // sharing support
 731   virtual void remove_unshareable_info();
 732   void field_names_and_sigs_iterate(OopClosure* closure);
 733 
 734   // jvm support
 735   jint compute_modifier_flags(TRAPS) const;
 736 
 737 public:
 738   // JVMTI support
 739   jint jvmti_class_status() const;
 740 
 741 #ifndef PRODUCT
 742  public:
 743   // Printing
 744   void oop_print_on      (oop obj, outputStream* st);
 745   void oop_print_value_on(oop obj, outputStream* st);
 746 
 747   void print_dependent_nmethods(bool verbose = false);
 748   bool is_dependent_nmethod(nmethod* nm);
 749 #endif
 750 
 751  public:
 752   // Verification
 753   const char* internal_name() const;
 754   void oop_verify_on(oop obj, outputStream* st);
 755 
 756 #ifndef PRODUCT
 757   static void verify_class_klass_nonstatic_oop_maps(klassOop k) PRODUCT_RETURN;
 758 #endif
 759 };
 760 
 761 inline methodOop instanceKlass::method_at_vtable(int index)  {
 762 #ifndef PRODUCT
 763   assert(index >= 0, "valid vtable index");
 764   if (DebugVtables) {
 765     verify_vtable_index(index);
 766   }
 767 #endif
 768   vtableEntry* ve = (vtableEntry*)start_of_vtable();
 769   return ve[index].method();
 770 }
 771 
 772 inline typeArrayOop instanceKlass::get_method_annotations_from(int idnum, objArrayOop annos) {
 773   if (annos == NULL || annos->length() <= idnum) {
 774     return NULL;
 775   }
 776   return typeArrayOop(annos->obj_at(idnum));
 777 }
 778 
 779 // for adding methods
 780 // UNSET_IDNUM return means no more ids available
 781 inline u2 instanceKlass::next_method_idnum() {
 782   if (_idnum_allocated_count == constMethodOopDesc::MAX_IDNUM) {
 783     return constMethodOopDesc::UNSET_IDNUM; // no more ids available
 784   } else {
 785     return _idnum_allocated_count++;
 786   }
 787 }
 788 
 789 
 790 // ValueObjs embedded in klass. Describes where oops are located in instances of this klass.
 791 
 792 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
 793  private:
 794   jushort _offset;    // Offset of first oop in oop-map block
 795   jushort _length;    // Length of oop-map block
 796  public:
 797   // Accessors
 798   jushort offset() const          { return _offset; }
 799   void set_offset(jushort offset) { _offset = offset; }
 800 
 801   jushort length() const          { return _length; }
 802   void set_length(jushort length) { _length = length; }
 803 };
 804 
 805 /* JNIid class for jfieldIDs only */
 806 class JNIid: public CHeapObj {
 807   friend class VMStructs;
 808  private:
 809   klassOop           _holder;
 810   JNIid*             _next;
 811   int                _offset;
 812 #ifdef ASSERT
 813   bool               _is_static_field_id;
 814 #endif
 815 
 816  public:
 817   // Accessors
 818   klassOop holder() const         { return _holder; }
 819   int offset() const              { return _offset; }
 820   JNIid* next()                   { return _next; }
 821   // Constructor
 822   JNIid(klassOop holder, int offset, JNIid* next);
 823   // Identifier lookup
 824   JNIid* find(int offset);
 825 
 826   // Garbage collection support
 827   oop* holder_addr() { return (oop*)&_holder; }
 828   void oops_do(OopClosure* f);
 829   static void deallocate(JNIid* id);
 830   // Debugging
 831 #ifdef ASSERT
 832   bool is_static_field_id() const { return _is_static_field_id; }
 833   void set_is_static_field_id()   { _is_static_field_id = true; }
 834 #endif
 835   void verify(klassOop holder);
 836 };
 837 
 838 
 839 // If breakpoints are more numerous than just JVMTI breakpoints,
 840 // consider compressing this data structure.
 841 // It is currently a simple linked list defined in methodOop.hpp.
 842 
 843 class BreakpointInfo;
 844 
 845 
 846 // A collection point for interesting information about the previous
 847 // version(s) of an instanceKlass. This class uses weak references to
 848 // the information so that the information may be collected as needed
 849 // by the system. A GrowableArray of PreviousVersionNodes is attached
 850 // to the instanceKlass as needed. See PreviousVersionWalker below.
 851 class PreviousVersionNode : public CHeapObj {
 852  private:
 853   jweak _prev_constant_pool;
 854   // If the previous version of the instanceKlass doesn't have any
 855   // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
 856   // EMCP methods have been collected, then _prev_EMCP_methods can
 857   // have a length of zero.
 858   GrowableArray<jweak>* _prev_EMCP_methods;
 859 
 860 public:
 861   PreviousVersionNode(jweak prev_constant_pool,
 862     GrowableArray<jweak>* prev_EMCP_methods);
 863   ~PreviousVersionNode();
 864   jweak prev_constant_pool() const {
 865     return _prev_constant_pool;
 866   }
 867   GrowableArray<jweak>* prev_EMCP_methods() const {
 868     return _prev_EMCP_methods;
 869   }
 870 };
 871 
 872 
 873 // A Handle-ized version of PreviousVersionNode.
 874 class PreviousVersionInfo : public ResourceObj {
 875  private:
 876   constantPoolHandle   _prev_constant_pool_handle;
 877   // If the previous version of the instanceKlass doesn't have any
 878   // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
 879   // methods cannot be collected while we hold a handle,
 880   // _prev_EMCP_methods should never have a length of zero.
 881   GrowableArray<methodHandle>* _prev_EMCP_method_handles;
 882 
 883 public:
 884   PreviousVersionInfo(PreviousVersionNode *pv_node);
 885   ~PreviousVersionInfo();
 886   constantPoolHandle prev_constant_pool_handle() const {
 887     return _prev_constant_pool_handle;
 888   }
 889   GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
 890     return _prev_EMCP_method_handles;
 891   }
 892 };
 893 
 894 
 895 // Helper object for walking previous versions. This helper cleans up
 896 // the Handles that it allocates when the helper object is destroyed.
 897 // The PreviousVersionInfo object returned by next_previous_version()
 898 // is only valid until a subsequent call to next_previous_version() or
 899 // the helper object is destroyed.
 900 class PreviousVersionWalker : public StackObj {
 901  private:
 902   GrowableArray<PreviousVersionNode *>* _previous_versions;
 903   int                                   _current_index;
 904   // Fields for cleaning up when we are done walking the previous versions:
 905   // A HandleMark for the PreviousVersionInfo handles:
 906   HandleMark                            _hm;
 907 
 908   // It would be nice to have a ResourceMark field in this helper also,
 909   // but the ResourceMark code says to be careful to delete handles held
 910   // in GrowableArrays _before_ deleting the GrowableArray. Since we
 911   // can't guarantee the order in which the fields are destroyed, we
 912   // have to let the creator of the PreviousVersionWalker object do
 913   // the right thing. Also, adding a ResourceMark here causes an
 914   // include loop.
 915 
 916   // A pointer to the current info object so we can handle the deletes.
 917   PreviousVersionInfo *                 _current_p;
 918 
 919  public:
 920   PreviousVersionWalker(instanceKlass *ik);
 921   ~PreviousVersionWalker();
 922 
 923   // Return the interesting information for the next previous version
 924   // of the klass. Returns NULL if there are no more previous versions.
 925   PreviousVersionInfo* next_previous_version();
 926 };