1 /* 2 * Copyright (c) 1997, 2013, 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 "oops/annotations.hpp" 30 #include "oops/constMethod.hpp" 31 #include "oops/fieldInfo.hpp" 32 #include "oops/instanceOop.hpp" 33 #include "oops/klassVtable.hpp" 34 #include "runtime/atomic.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 41 // An InstanceKlass is the VM level representation of a Java class. 42 // It contains all information needed for at class at execution runtime. 43 44 // InstanceKlass layout: 45 // [C++ vtbl pointer ] Klass 46 // [subtype cache ] Klass 47 // [instance size ] Klass 48 // [java mirror ] Klass 49 // [super ] Klass 50 // [access_flags ] Klass 51 // [name ] Klass 52 // [first subklass ] Klass 53 // [next sibling ] Klass 54 // [array klasses ] 55 // [methods ] 56 // [local interfaces ] 57 // [transitive interfaces ] 58 // [fields ] 59 // [constants ] 60 // [class loader ] 61 // [protection domain ] 62 // [signers ] 63 // [source file name ] 64 // [inner classes ] 65 // [static field size ] 66 // [nonstatic field size ] 67 // [static oop fields size ] 68 // [nonstatic oop maps size ] 69 // [has finalize method ] 70 // [deoptimization mark bit ] 71 // [initialization state ] 72 // [initializing thread ] 73 // [Java vtable length ] 74 // [oop map cache (stack maps) ] 75 // [EMBEDDED Java vtable ] size in words = vtable_len 76 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size 77 // The embedded nonstatic oop-map blocks are short pairs (offset, length) 78 // indicating where oops are located in instances of this klass. 79 // [EMBEDDED implementor of the interface] only exist for interface 80 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled) 81 82 83 // forward declaration for class -- see below for definition 84 class SuperTypeClosure; 85 class JNIid; 86 class jniIdMapBase; 87 class BreakpointInfo; 88 class fieldDescriptor; 89 class DepChange; 90 class nmethodBucket; 91 class PreviousVersionNode; 92 class JvmtiCachedClassFieldMap; 93 94 // This is used in iterators below. 95 class FieldClosure: public StackObj { 96 public: 97 virtual void do_field(fieldDescriptor* fd) = 0; 98 }; 99 100 #ifndef PRODUCT 101 // Print fields. 102 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields. 103 class FieldPrinter: public FieldClosure { 104 oop _obj; 105 outputStream* _st; 106 public: 107 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {} 108 void do_field(fieldDescriptor* fd); 109 }; 110 #endif // !PRODUCT 111 112 // ValueObjs embedded in klass. Describes where oops are located in instances of 113 // this klass. 114 class OopMapBlock VALUE_OBJ_CLASS_SPEC { 115 public: 116 // Byte offset of the first oop mapped by this block. 117 int offset() const { return _offset; } 118 void set_offset(int offset) { _offset = offset; } 119 120 // Number of oops in this block. 121 uint count() const { return _count; } 122 void set_count(uint count) { _count = count; } 123 124 // sizeof(OopMapBlock) in HeapWords. 125 static const int size_in_words() { 126 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >> 127 LogHeapWordSize; 128 } 129 130 private: 131 int _offset; 132 uint _count; 133 }; 134 135 class InstanceKlass: public Klass { 136 friend class VMStructs; 137 friend class ClassFileParser; 138 friend class CompileReplay; 139 140 protected: 141 // Constructor 142 InstanceKlass(int vtable_len, 143 int itable_len, 144 int static_field_size, 145 int nonstatic_oop_map_size, 146 ReferenceType rt, 147 AccessFlags access_flags, 148 bool is_anonymous); 149 public: 150 static InstanceKlass* allocate_instance_klass( 151 ClassLoaderData* loader_data, 152 int vtable_len, 153 int itable_len, 154 int static_field_size, 155 int nonstatic_oop_map_size, 156 ReferenceType rt, 157 AccessFlags access_flags, 158 Symbol* name, 159 Klass* super_klass, 160 bool is_anonymous, 161 TRAPS); 162 163 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); } 164 165 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description 166 // of the class loading & initialization procedure, and the use of the states. 167 enum ClassState { 168 allocated, // allocated (but not yet linked) 169 loaded, // loaded and inserted in class hierarchy (but not linked yet) 170 linked, // successfully linked/verified (but not initialized yet) 171 being_initialized, // currently running class initializer 172 fully_initialized, // initialized (successfull final state) 173 initialization_error // error happened during initialization 174 }; 175 176 static int number_of_instance_classes() { return _total_instanceKlass_count; } 177 178 private: 179 static volatile int _total_instanceKlass_count; 180 181 protected: 182 // Protection domain. 183 oop _protection_domain; 184 // Class signers. 185 objArrayOop _signers; 186 // Initialization lock. Must be one per class and it has to be a VM internal 187 // object so java code cannot lock it (like the mirror) 188 // It has to be an object not a Mutex because it's held through java calls. 189 volatile oop _init_lock; 190 191 // Annotations for this class 192 Annotations* _annotations; 193 // Array classes holding elements of this class. 194 Klass* _array_klasses; 195 // Constant pool for this class. 196 ConstantPool* _constants; 197 // The InnerClasses attribute and EnclosingMethod attribute. The 198 // _inner_classes is an array of shorts. If the class has InnerClasses 199 // attribute, then the _inner_classes array begins with 4-tuples of shorts 200 // [inner_class_info_index, outer_class_info_index, 201 // inner_name_index, inner_class_access_flags] for the InnerClasses 202 // attribute. If the EnclosingMethod attribute exists, it occupies the 203 // last two shorts [class_index, method_index] of the array. If only 204 // the InnerClasses attribute exists, the _inner_classes array length is 205 // number_of_inner_classes * 4. If the class has both InnerClasses 206 // and EnclosingMethod attributes the _inner_classes array length is 207 // number_of_inner_classes * 4 + enclosing_method_attribute_size. 208 Array<jushort>* _inner_classes; 209 210 // Name of source file containing this klass, NULL if not specified. 211 Symbol* _source_file_name; 212 // the source debug extension for this klass, NULL if not specified. 213 // Specified as UTF-8 string without terminating zero byte in the classfile, 214 // it is stored in the instanceklass as a NULL-terminated UTF-8 string 215 char* _source_debug_extension; 216 // Generic signature, or null if none. 217 Symbol* _generic_signature; 218 // Array name derived from this class which needs unreferencing 219 // if this class is unloaded. 220 Symbol* _array_name; 221 222 // Number of heapOopSize words used by non-static fields in this klass 223 // (including inherited fields but after header_size()). 224 int _nonstatic_field_size; 225 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass 226 u2 _static_oop_field_count;// number of static oop fields in this klass 227 u2 _java_fields_count; // The number of declared Java fields 228 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks 229 230 // _is_marked_dependent can be set concurrently, thus cannot be part of the 231 // _misc_flags. 232 bool _is_marked_dependent; // used for marking during flushing and deoptimization 233 234 enum { 235 _misc_rewritten = 1 << 0, // methods rewritten. 236 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops 237 _misc_should_verify_class = 1 << 2, // allow caching of preverification 238 _misc_is_anonymous = 1 << 3, // has embedded _inner_classes field 239 _misc_is_contended = 1 << 4, // marked with contended annotation 240 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods 241 }; 242 u2 _misc_flags; 243 u2 _minor_version; // minor version number of class file 244 u2 _major_version; // major version number of class file 245 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization) 246 int _vtable_len; // length of Java vtable (in words) 247 int _itable_len; // length of Java itable (in words) 248 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily) 249 JNIid* _jni_ids; // First JNI identifier for static fields in this class 250 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none 251 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL 252 nmethodBucket* _dependencies; // list of dependent nmethods 253 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class 254 BreakpointInfo* _breakpoints; // bpt lists, managed by Method* 255 // Array of interesting part(s) of the previous version(s) of this 256 // InstanceKlass. See PreviousVersionWalker below. 257 GrowableArray<PreviousVersionNode *>* _previous_versions; 258 // JVMTI fields can be moved to their own structure - see 6315920 259 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH 260 jint _cached_class_file_len; // JVMTI: length of above 261 262 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change 263 264 // Class states are defined as ClassState (see above). 265 // Place the _init_state here to utilize the unused 2-byte after 266 // _idnum_allocated_count. 267 u1 _init_state; // state of class 268 u1 _reference_type; // reference type 269 270 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration 271 272 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies 273 274 // Method array. 275 Array<Method*>* _methods; 276 // Interface (Klass*s) this class declares locally to implement. 277 Array<Klass*>* _local_interfaces; 278 // Interface (Klass*s) this class implements transitively. 279 Array<Klass*>* _transitive_interfaces; 280 // Int array containing the original order of method in the class file (for JVMTI). 281 Array<int>* _method_ordering; 282 // Instance and static variable information, starts with 6-tuples of shorts 283 // [access, name index, sig index, initval index, low_offset, high_offset] 284 // for all fields, followed by the generic signature data at the end of 285 // the array. Only fields with generic signature attributes have the generic 286 // signature data set in the array. The fields array looks like following: 287 // 288 // f1: [access, name index, sig index, initial value index, low_offset, high_offset] 289 // f2: [access, name index, sig index, initial value index, low_offset, high_offset] 290 // ... 291 // fn: [access, name index, sig index, initial value index, low_offset, high_offset] 292 // [generic signature index] 293 // [generic signature index] 294 // ... 295 Array<u2>* _fields; 296 297 // embedded Java vtable follows here 298 // embedded Java itables follows here 299 // embedded static fields follows here 300 // embedded nonstatic oop-map blocks follows here 301 // embedded implementor of this interface follows here 302 // The embedded implementor only exists if the current klass is an 303 // iterface. The possible values of the implementor fall into following 304 // three cases: 305 // NULL: no implementor. 306 // A Klass* that's not itself: one implementor. 307 // Itsef: more than one implementors. 308 // embedded host klass follows here 309 // The embedded host klass only exists in an anonymous class for 310 // dynamic language support (JSR 292 enabled). The host class grants 311 // its access privileges to this class also. The host class is either 312 // named, or a previously loaded anonymous class. A non-anonymous class 313 // or an anonymous class loaded through normal classloading does not 314 // have this embedded field. 315 // 316 317 friend class SystemDictionary; 318 319 public: 320 bool has_nonstatic_fields() const { 321 return (_misc_flags & _misc_has_nonstatic_fields) != 0; 322 } 323 void set_has_nonstatic_fields(bool b) { 324 if (b) { 325 _misc_flags |= _misc_has_nonstatic_fields; 326 } else { 327 _misc_flags &= ~_misc_has_nonstatic_fields; 328 } 329 } 330 331 // field sizes 332 int nonstatic_field_size() const { return _nonstatic_field_size; } 333 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; } 334 335 int static_field_size() const { return _static_field_size; } 336 void set_static_field_size(int size) { _static_field_size = size; } 337 338 int static_oop_field_count() const { return (int)_static_oop_field_count; } 339 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; } 340 341 // Java vtable 342 int vtable_length() const { return _vtable_len; } 343 void set_vtable_length(int len) { _vtable_len = len; } 344 345 // Java itable 346 int itable_length() const { return _itable_len; } 347 void set_itable_length(int len) { _itable_len = len; } 348 349 // array klasses 350 Klass* array_klasses() const { return _array_klasses; } 351 void set_array_klasses(Klass* k) { _array_klasses = k; } 352 353 // methods 354 Array<Method*>* methods() const { return _methods; } 355 void set_methods(Array<Method*>* a) { _methods = a; } 356 Method* method_with_idnum(int idnum); 357 358 // method ordering 359 Array<int>* method_ordering() const { return _method_ordering; } 360 void set_method_ordering(Array<int>* m) { _method_ordering = m; } 361 void copy_method_ordering(intArray* m, TRAPS); 362 363 // interfaces 364 Array<Klass*>* local_interfaces() const { return _local_interfaces; } 365 void set_local_interfaces(Array<Klass*>* a) { 366 guarantee(_local_interfaces == NULL || a == NULL, "Just checking"); 367 _local_interfaces = a; } 368 369 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; } 370 void set_transitive_interfaces(Array<Klass*>* a) { 371 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking"); 372 _transitive_interfaces = a; 373 } 374 375 private: 376 friend class fieldDescriptor; 377 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); } 378 379 public: 380 int field_offset (int index) const { return field(index)->offset(); } 381 int field_access_flags(int index) const { return field(index)->access_flags(); } 382 Symbol* field_name (int index) const { return field(index)->name(constants()); } 383 Symbol* field_signature (int index) const { return field(index)->signature(constants()); } 384 385 // Number of Java declared fields 386 int java_fields_count() const { return (int)_java_fields_count; } 387 388 Array<u2>* fields() const { return _fields; } 389 void set_fields(Array<u2>* f, u2 java_fields_count) { 390 guarantee(_fields == NULL || f == NULL, "Just checking"); 391 _fields = f; 392 _java_fields_count = java_fields_count; 393 } 394 395 // inner classes 396 Array<u2>* inner_classes() const { return _inner_classes; } 397 void set_inner_classes(Array<u2>* f) { _inner_classes = f; } 398 399 enum InnerClassAttributeOffset { 400 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814 401 inner_class_inner_class_info_offset = 0, 402 inner_class_outer_class_info_offset = 1, 403 inner_class_inner_name_offset = 2, 404 inner_class_access_flags_offset = 3, 405 inner_class_next_offset = 4 406 }; 407 408 enum EnclosingMethodAttributeOffset { 409 enclosing_method_class_index_offset = 0, 410 enclosing_method_method_index_offset = 1, 411 enclosing_method_attribute_size = 2 412 }; 413 414 // method override check 415 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS); 416 417 // package 418 bool is_same_class_package(Klass* class2); 419 bool is_same_class_package(oop classloader2, Symbol* classname2); 420 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2); 421 422 // find an enclosing class (defined where original code was, in jvm.cpp!) 423 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) { 424 instanceKlassHandle self(THREAD, this); 425 return compute_enclosing_class_impl(self, inner_is_member, THREAD); 426 } 427 static Klass* compute_enclosing_class_impl(instanceKlassHandle self, 428 bool* inner_is_member, TRAPS); 429 430 // tell if two classes have the same enclosing class (at package level) 431 bool is_same_package_member(Klass* class2, TRAPS) { 432 instanceKlassHandle self(THREAD, this); 433 return is_same_package_member_impl(self, class2, THREAD); 434 } 435 static bool is_same_package_member_impl(instanceKlassHandle self, 436 Klass* class2, TRAPS); 437 438 // initialization state 439 bool is_loaded() const { return _init_state >= loaded; } 440 bool is_linked() const { return _init_state >= linked; } 441 bool is_initialized() const { return _init_state == fully_initialized; } 442 bool is_not_initialized() const { return _init_state < being_initialized; } 443 bool is_being_initialized() const { return _init_state == being_initialized; } 444 bool is_in_error_state() const { return _init_state == initialization_error; } 445 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; } 446 ClassState init_state() { return (ClassState)_init_state; } 447 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; } 448 449 // defineClass specified verification 450 bool should_verify_class() const { 451 return (_misc_flags & _misc_should_verify_class) != 0; 452 } 453 void set_should_verify_class(bool value) { 454 if (value) { 455 _misc_flags |= _misc_should_verify_class; 456 } else { 457 _misc_flags &= ~_misc_should_verify_class; 458 } 459 } 460 461 // marking 462 bool is_marked_dependent() const { return _is_marked_dependent; } 463 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; } 464 465 // initialization (virtuals from Klass) 466 bool should_be_initialized() const; // means that initialize should be called 467 void initialize(TRAPS); 468 void link_class(TRAPS); 469 bool link_class_or_fail(TRAPS); // returns false on failure 470 void unlink_class(); 471 void rewrite_class(TRAPS); 472 void link_methods(TRAPS); 473 Method* class_initializer(); 474 475 // set the class to initialized if no static initializer is present 476 void eager_initialize(Thread *thread); 477 478 // reference type 479 ReferenceType reference_type() const { return (ReferenceType)_reference_type; } 480 void set_reference_type(ReferenceType t) { 481 assert(t == (u1)t, "overflow"); 482 _reference_type = (u1)t; 483 } 484 485 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); } 486 487 // find local field, returns true if found 488 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const; 489 // find field in direct superinterfaces, returns the interface in which the field is defined 490 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const; 491 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined 492 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const; 493 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined 494 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const; 495 496 // find a non-static or static field given its offset within the class. 497 bool contains_field_offset(int offset) { 498 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size()); 499 } 500 501 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; 502 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; 503 504 // find a local method (returns NULL if not found) 505 Method* find_method(Symbol* name, Symbol* signature) const; 506 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature); 507 508 // lookup operation (returns NULL if not found) 509 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const; 510 511 // lookup a method in all the interfaces that this class implements 512 // (returns NULL if not found) 513 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature) const; 514 515 // Find method indices by name. If a method with the specified name is 516 // found the index to the first method is returned, and 'end' is filled in 517 // with the index of first non-name-matching method. If no method is found 518 // -1 is returned. 519 int find_method_by_name(Symbol* name, int* end); 520 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end); 521 522 // constant pool 523 ConstantPool* constants() const { return _constants; } 524 void set_constants(ConstantPool* c) { _constants = c; } 525 526 // protection domain 527 oop protection_domain() { return _protection_domain; } 528 void set_protection_domain(oop pd) { klass_oop_store(&_protection_domain, pd); } 529 530 // host class 531 Klass* host_klass() const { 532 Klass** hk = (Klass**)adr_host_klass(); 533 if (hk == NULL) { 534 return NULL; 535 } else { 536 return *hk; 537 } 538 } 539 void set_host_klass(Klass* host) { 540 assert(is_anonymous(), "not anonymous"); 541 Klass** addr = (Klass**)adr_host_klass(); 542 assert(addr != NULL, "no reversed space"); 543 if (addr != NULL) { 544 *addr = host; 545 } 546 } 547 bool is_anonymous() const { 548 return (_misc_flags & _misc_is_anonymous) != 0; 549 } 550 void set_is_anonymous(bool value) { 551 if (value) { 552 _misc_flags |= _misc_is_anonymous; 553 } else { 554 _misc_flags &= ~_misc_is_anonymous; 555 } 556 } 557 558 // Oop that keeps the metadata for this class from being unloaded 559 // in places where the metadata is stored in other places, like nmethods 560 oop klass_holder() const { 561 return is_anonymous() ? java_mirror() : class_loader(); 562 } 563 564 bool is_contended() const { 565 return (_misc_flags & _misc_is_contended) != 0; 566 } 567 void set_is_contended(bool value) { 568 if (value) { 569 _misc_flags |= _misc_is_contended; 570 } else { 571 _misc_flags &= ~_misc_is_contended; 572 } 573 } 574 575 // signers 576 objArrayOop signers() const { return _signers; } 577 void set_signers(objArrayOop s) { klass_oop_store((oop*)&_signers, s); } 578 579 // source file name 580 Symbol* source_file_name() const { return _source_file_name; } 581 void set_source_file_name(Symbol* n); 582 583 // minor and major version numbers of class file 584 u2 minor_version() const { return _minor_version; } 585 void set_minor_version(u2 minor_version) { _minor_version = minor_version; } 586 u2 major_version() const { return _major_version; } 587 void set_major_version(u2 major_version) { _major_version = major_version; } 588 589 // source debug extension 590 char* source_debug_extension() const { return _source_debug_extension; } 591 void set_source_debug_extension(char* array, int length); 592 593 // symbol unloading support (refcount already added) 594 Symbol* array_name() { return _array_name; } 595 void set_array_name(Symbol* name) { assert(_array_name == NULL || name == NULL, "name already created"); _array_name = name; } 596 597 // nonstatic oop-map blocks 598 static int nonstatic_oop_map_size(unsigned int oop_map_count) { 599 return oop_map_count * OopMapBlock::size_in_words(); 600 } 601 unsigned int nonstatic_oop_map_count() const { 602 return _nonstatic_oop_map_size / OopMapBlock::size_in_words(); 603 } 604 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; } 605 void set_nonstatic_oop_map_size(int words) { 606 _nonstatic_oop_map_size = words; 607 } 608 609 // RedefineClasses() support for previous versions: 610 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods, 611 int emcp_method_count); 612 // If the _previous_versions array is non-NULL, then this klass 613 // has been redefined at least once even if we aren't currently 614 // tracking a previous version. 615 bool has_been_redefined() const { return _previous_versions != NULL; } 616 bool has_previous_version() const; 617 void init_previous_versions() { 618 _previous_versions = NULL; 619 } 620 GrowableArray<PreviousVersionNode *>* previous_versions() const { 621 return _previous_versions; 622 } 623 624 static void purge_previous_versions(InstanceKlass* ik); 625 626 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation 627 void set_cached_class_file(unsigned char *class_file_bytes, 628 jint class_file_len) { _cached_class_file_len = class_file_len; 629 _cached_class_file_bytes = class_file_bytes; } 630 jint get_cached_class_file_len() { return _cached_class_file_len; } 631 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; } 632 633 // JVMTI: Support for caching of field indices, types, and offsets 634 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) { 635 _jvmti_cached_class_field_map = descriptor; 636 } 637 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const { 638 return _jvmti_cached_class_field_map; 639 } 640 641 bool has_default_methods() const { 642 return (_misc_flags & _misc_has_default_methods) != 0; 643 } 644 void set_has_default_methods(bool b) { 645 if (b) { 646 _misc_flags |= _misc_has_default_methods; 647 } else { 648 _misc_flags &= ~_misc_has_default_methods; 649 } 650 } 651 652 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available 653 inline u2 next_method_idnum(); 654 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; } 655 656 // generics support 657 Symbol* generic_signature() const { return _generic_signature; } 658 void set_generic_signature(Symbol* sig) { _generic_signature = sig; } 659 660 u2 enclosing_method_data(int offset); 661 u2 enclosing_method_class_index() { 662 return enclosing_method_data(enclosing_method_class_index_offset); 663 } 664 u2 enclosing_method_method_index() { 665 return enclosing_method_data(enclosing_method_method_index_offset); 666 } 667 void set_enclosing_method_indices(u2 class_index, 668 u2 method_index); 669 670 // jmethodID support 671 static jmethodID get_jmethod_id(instanceKlassHandle ik_h, 672 methodHandle method_h); 673 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h, 674 size_t idnum, jmethodID new_id, jmethodID* new_jmeths, 675 jmethodID* to_dealloc_id_p, 676 jmethodID** to_dealloc_jmeths_p); 677 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum, 678 size_t *length_p, jmethodID* id_p); 679 jmethodID jmethod_id_or_null(Method* method); 680 681 // cached itable index support 682 void set_cached_itable_index(size_t idnum, int index); 683 int cached_itable_index(size_t idnum); 684 685 // annotations support 686 Annotations* annotations() const { return _annotations; } 687 void set_annotations(Annotations* anno) { _annotations = anno; } 688 689 AnnotationArray* class_annotations() const { 690 return (_annotations != NULL) ? _annotations->class_annotations() : NULL; 691 } 692 Array<AnnotationArray*>* fields_annotations() const { 693 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL; 694 } 695 AnnotationArray* class_type_annotations() const { 696 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL; 697 } 698 Array<AnnotationArray*>* fields_type_annotations() const { 699 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL; 700 } 701 // allocation 702 instanceOop allocate_instance(TRAPS); 703 704 // additional member function to return a handle 705 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); } 706 707 objArrayOop allocate_objArray(int n, int length, TRAPS); 708 // Helper function 709 static instanceOop register_finalizer(instanceOop i, TRAPS); 710 711 // Check whether reflection/jni/jvm code is allowed to instantiate this class; 712 // if not, throw either an Error or an Exception. 713 virtual void check_valid_for_instantiation(bool throwError, TRAPS); 714 715 // initialization 716 void call_class_initializer(TRAPS); 717 void set_initialization_state_and_notify(ClassState state, TRAPS); 718 719 // OopMapCache support 720 OopMapCache* oop_map_cache() { return _oop_map_cache; } 721 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; } 722 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry); 723 724 // JNI identifier support (for static fields - for jni performance) 725 JNIid* jni_ids() { return _jni_ids; } 726 void set_jni_ids(JNIid* ids) { _jni_ids = ids; } 727 JNIid* jni_id_for(int offset); 728 729 // maintenance of deoptimization dependencies 730 int mark_dependent_nmethods(DepChange& changes); 731 void add_dependent_nmethod(nmethod* nm); 732 void remove_dependent_nmethod(nmethod* nm); 733 734 // On-stack replacement support 735 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; }; 736 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; }; 737 void add_osr_nmethod(nmethod* n); 738 void remove_osr_nmethod(nmethod* n); 739 nmethod* lookup_osr_nmethod(Method* const m, int bci, int level, bool match_level) const; 740 741 // Breakpoint support (see methods on Method* for details) 742 BreakpointInfo* breakpoints() const { return _breakpoints; }; 743 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; }; 744 745 // support for stub routines 746 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); } 747 TRACE_DEFINE_OFFSET; 748 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); } 749 750 // subclass/subinterface checks 751 bool implements_interface(Klass* k) const; 752 753 // Access to the implementor of an interface. 754 Klass* implementor() const 755 { 756 Klass** k = adr_implementor(); 757 if (k == NULL) { 758 return NULL; 759 } else { 760 return *k; 761 } 762 } 763 764 void set_implementor(Klass* k) { 765 assert(is_interface(), "not interface"); 766 Klass** addr = adr_implementor(); 767 assert(addr != NULL, "null addr"); 768 if (addr != NULL) { 769 *addr = k; 770 } 771 } 772 773 int nof_implementors() const { 774 Klass* k = implementor(); 775 if (k == NULL) { 776 return 0; 777 } else if (k != this) { 778 return 1; 779 } else { 780 return 2; 781 } 782 } 783 784 void add_implementor(Klass* k); // k is a new class that implements this interface 785 void init_implementor(); // initialize 786 787 // link this class into the implementors list of every interface it implements 788 void process_interfaces(Thread *thread); 789 790 // virtual operations from Klass 791 bool is_leaf_class() const { return _subklass == NULL; } 792 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots); 793 bool compute_is_subtype_of(Klass* k); 794 bool can_be_primary_super_slow() const; 795 int oop_size(oop obj) const { return size_helper(); } 796 bool oop_is_instance_slow() const { return true; } 797 798 // Iterators 799 void do_local_static_fields(FieldClosure* cl); 800 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields 801 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS); 802 803 void methods_do(void f(Method* method)); 804 void array_klasses_do(void f(Klass* k)); 805 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS); 806 void with_array_klasses_do(void f(Klass* k)); 807 bool super_types_do(SuperTypeClosure* blk); 808 809 // Casting from Klass* 810 static InstanceKlass* cast(Klass* k) { 811 assert(k->is_klass(), "must be"); 812 assert(k->oop_is_instance(), "cast to InstanceKlass"); 813 return (InstanceKlass*) k; 814 } 815 816 InstanceKlass* java_super() const { 817 return (super() == NULL) ? NULL : cast(super()); 818 } 819 820 // Sizing (in words) 821 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); } 822 823 static int size(int vtable_length, int itable_length, 824 int nonstatic_oop_map_size, 825 bool is_interface, bool is_anonymous) { 826 return align_object_size(header_size() + 827 align_object_offset(vtable_length) + 828 align_object_offset(itable_length) + 829 ((is_interface || is_anonymous) ? 830 align_object_offset(nonstatic_oop_map_size) : 831 nonstatic_oop_map_size) + 832 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) + 833 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0)); 834 } 835 int size() const { return size(vtable_length(), 836 itable_length(), 837 nonstatic_oop_map_size(), 838 is_interface(), 839 is_anonymous()); 840 } 841 #if INCLUDE_SERVICES 842 virtual void collect_statistics(KlassSizeStats *sz) const; 843 #endif 844 845 static int vtable_start_offset() { return header_size(); } 846 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; } 847 848 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); } 849 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); } 850 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; } 851 852 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); } 853 854 address static_field_addr(int offset); 855 856 OopMapBlock* start_of_nonstatic_oop_maps() const { 857 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length())); 858 } 859 860 Klass** end_of_nonstatic_oop_maps() const { 861 return (Klass**)(start_of_nonstatic_oop_maps() + 862 nonstatic_oop_map_count()); 863 } 864 865 Klass** adr_implementor() const { 866 if (is_interface()) { 867 return (Klass**)end_of_nonstatic_oop_maps(); 868 } else { 869 return NULL; 870 } 871 }; 872 873 Klass** adr_host_klass() const { 874 if (is_anonymous()) { 875 Klass** adr_impl = adr_implementor(); 876 if (adr_impl != NULL) { 877 return adr_impl + 1; 878 } else { 879 return end_of_nonstatic_oop_maps(); 880 } 881 } else { 882 return NULL; 883 } 884 } 885 886 // Allocation profiling support 887 juint alloc_size() const { return _alloc_count * size_helper(); } 888 void set_alloc_size(juint n) {} 889 890 // Use this to return the size of an instance in heap words: 891 int size_helper() const { 892 return layout_helper_to_size_helper(layout_helper()); 893 } 894 895 // This bit is initialized in classFileParser.cpp. 896 // It is false under any of the following conditions: 897 // - the class is abstract (including any interface) 898 // - the class has a finalizer (if !RegisterFinalizersAtInit) 899 // - the class size is larger than FastAllocateSizeLimit 900 // - the class is java/lang/Class, which cannot be allocated directly 901 bool can_be_fastpath_allocated() const { 902 return !layout_helper_needs_slow_path(layout_helper()); 903 } 904 905 // Java vtable/itable 906 klassVtable* vtable() const; // return new klassVtable wrapper 907 inline Method* method_at_vtable(int index); 908 klassItable* itable() const; // return new klassItable wrapper 909 Method* method_at_itable(Klass* holder, int index, TRAPS); 910 911 // Garbage collection 912 virtual void oops_do(OopClosure* cl); 913 914 void oop_follow_contents(oop obj); 915 int oop_adjust_pointers(oop obj); 916 917 void clean_implementors_list(BoolObjectClosure* is_alive); 918 void clean_method_data(BoolObjectClosure* is_alive); 919 920 // Explicit metaspace deallocation of fields 921 // For RedefineClasses and class file parsing errors, we need to deallocate 922 // instanceKlasses and the metadata they point to. 923 void deallocate_contents(ClassLoaderData* loader_data); 924 static void deallocate_methods(ClassLoaderData* loader_data, 925 Array<Method*>* methods); 926 void static deallocate_interfaces(ClassLoaderData* loader_data, 927 Klass* super_klass, 928 Array<Klass*>* local_interfaces, 929 Array<Klass*>* transitive_interfaces); 930 931 // The constant pool is on stack if any of the methods are executing or 932 // referenced by handles. 933 bool on_stack() const { return _constants->on_stack(); } 934 935 void release_C_heap_structures(); 936 937 // Parallel Scavenge and Parallel Old 938 PARALLEL_GC_DECLS 939 940 // Naming 941 const char* signature_name() const; 942 943 // Iterators 944 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) { 945 return oop_oop_iterate_v(obj, blk); 946 } 947 948 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) { 949 return oop_oop_iterate_v_m(obj, blk, mr); 950 } 951 952 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \ 953 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \ 954 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \ 955 MemRegion mr); 956 957 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL) 958 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL) 959 960 #if INCLUDE_ALL_GCS 961 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \ 962 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk); 963 964 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL) 965 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL) 966 #endif // INCLUDE_ALL_GCS 967 968 u2 idnum_allocated_count() const { return _idnum_allocated_count; } 969 private: 970 // initialization state 971 #ifdef ASSERT 972 void set_init_state(ClassState state); 973 #else 974 void set_init_state(ClassState state) { _init_state = (u1)state; } 975 #endif 976 void set_rewritten() { _misc_flags |= _misc_rewritten; } 977 void set_init_thread(Thread *thread) { _init_thread = thread; } 978 979 // The RedefineClasses() API can cause new method idnums to be needed 980 // which will cause the caches to grow. Safety requires different 981 // cache management logic if the caches can grow instead of just 982 // going from NULL to non-NULL. 983 bool idnum_can_increment() const { return has_been_redefined(); } 984 jmethodID* methods_jmethod_ids_acquire() const 985 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); } 986 void release_set_methods_jmethod_ids(jmethodID* jmeths) 987 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); } 988 989 int* methods_cached_itable_indices_acquire() const 990 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); } 991 void release_set_methods_cached_itable_indices(int* indices) 992 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); } 993 994 // Lock during initialization 995 volatile oop init_lock() const; 996 void set_init_lock(oop value) { klass_oop_store(&_init_lock, value); } 997 void fence_and_clear_init_lock(); // after fully_initialized 998 999 // Offsets for memory management 1000 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;} 1001 oop* adr_signers() const { return (oop*)&this->_signers;} 1002 oop* adr_init_lock() const { return (oop*)&this->_init_lock;} 1003 1004 // Static methods that are used to implement member methods where an exposed this pointer 1005 // is needed due to possible GCs 1006 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); 1007 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); 1008 static void initialize_impl (instanceKlassHandle this_oop, TRAPS); 1009 static void eager_initialize_impl (instanceKlassHandle this_oop); 1010 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS); 1011 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS); 1012 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS); 1013 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS); 1014 /* jni_id_for_impl for jfieldID only */ 1015 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset); 1016 1017 // Returns the array class for the n'th dimension 1018 Klass* array_klass_impl(bool or_null, int n, TRAPS); 1019 1020 // Returns the array class with this class as element type 1021 Klass* array_klass_impl(bool or_null, TRAPS); 1022 1023 public: 1024 // CDS support - remove and restore oops from metadata. Oops are not shared. 1025 virtual void remove_unshareable_info(); 1026 virtual void restore_unshareable_info(TRAPS); 1027 1028 // jvm support 1029 jint compute_modifier_flags(TRAPS) const; 1030 1031 public: 1032 // JVMTI support 1033 jint jvmti_class_status() const; 1034 1035 public: 1036 // Printing 1037 #ifndef PRODUCT 1038 void print_on(outputStream* st) const; 1039 #endif 1040 void print_value_on(outputStream* st) const; 1041 1042 void oop_print_value_on(oop obj, outputStream* st); 1043 1044 #ifndef PRODUCT 1045 void oop_print_on (oop obj, outputStream* st); 1046 1047 void print_dependent_nmethods(bool verbose = false); 1048 bool is_dependent_nmethod(nmethod* nm); 1049 #endif 1050 1051 const char* internal_name() const; 1052 1053 // Verification 1054 void verify_on(outputStream* st); 1055 1056 void oop_verify_on(oop obj, outputStream* st); 1057 }; 1058 1059 inline Method* InstanceKlass::method_at_vtable(int index) { 1060 #ifndef PRODUCT 1061 assert(index >= 0, "valid vtable index"); 1062 if (DebugVtables) { 1063 verify_vtable_index(index); 1064 } 1065 #endif 1066 vtableEntry* ve = (vtableEntry*)start_of_vtable(); 1067 return ve[index].method(); 1068 } 1069 1070 // for adding methods 1071 // UNSET_IDNUM return means no more ids available 1072 inline u2 InstanceKlass::next_method_idnum() { 1073 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) { 1074 return ConstMethod::UNSET_IDNUM; // no more ids available 1075 } else { 1076 return _idnum_allocated_count++; 1077 } 1078 } 1079 1080 1081 /* JNIid class for jfieldIDs only */ 1082 class JNIid: public CHeapObj<mtClass> { 1083 friend class VMStructs; 1084 private: 1085 Klass* _holder; 1086 JNIid* _next; 1087 int _offset; 1088 #ifdef ASSERT 1089 bool _is_static_field_id; 1090 #endif 1091 1092 public: 1093 // Accessors 1094 Klass* holder() const { return _holder; } 1095 int offset() const { return _offset; } 1096 JNIid* next() { return _next; } 1097 // Constructor 1098 JNIid(Klass* holder, int offset, JNIid* next); 1099 // Identifier lookup 1100 JNIid* find(int offset); 1101 1102 bool find_local_field(fieldDescriptor* fd) { 1103 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd); 1104 } 1105 1106 static void deallocate(JNIid* id); 1107 // Debugging 1108 #ifdef ASSERT 1109 bool is_static_field_id() const { return _is_static_field_id; } 1110 void set_is_static_field_id() { _is_static_field_id = true; } 1111 #endif 1112 void verify(Klass* holder); 1113 }; 1114 1115 1116 // If breakpoints are more numerous than just JVMTI breakpoints, 1117 // consider compressing this data structure. 1118 // It is currently a simple linked list defined in method.hpp. 1119 1120 class BreakpointInfo; 1121 1122 1123 // A collection point for interesting information about the previous 1124 // version(s) of an InstanceKlass. This class uses weak references to 1125 // the information so that the information may be collected as needed 1126 // by the system. If the information is shared, then a regular 1127 // reference must be used because a weak reference would be seen as 1128 // collectible. A GrowableArray of PreviousVersionNodes is attached 1129 // to the InstanceKlass as needed. See PreviousVersionWalker below. 1130 class PreviousVersionNode : public CHeapObj<mtClass> { 1131 private: 1132 // A shared ConstantPool is never collected so we'll always have 1133 // a reference to it so we can update items in the cache. We'll 1134 // have a weak reference to a non-shared ConstantPool until all 1135 // of the methods (EMCP or obsolete) have been collected; the 1136 // non-shared ConstantPool becomes collectible at that point. 1137 ConstantPool* _prev_constant_pool; // regular or weak reference 1138 bool _prev_cp_is_weak; // true if not a shared ConstantPool 1139 1140 // If the previous version of the InstanceKlass doesn't have any 1141 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the 1142 // EMCP methods have been collected, then _prev_EMCP_methods can 1143 // have a length of zero. 1144 GrowableArray<Method*>* _prev_EMCP_methods; 1145 1146 public: 1147 PreviousVersionNode(ConstantPool* prev_constant_pool, bool prev_cp_is_weak, 1148 GrowableArray<Method*>* prev_EMCP_methods); 1149 ~PreviousVersionNode(); 1150 ConstantPool* prev_constant_pool() const { 1151 return _prev_constant_pool; 1152 } 1153 GrowableArray<Method*>* prev_EMCP_methods() const { 1154 return _prev_EMCP_methods; 1155 } 1156 }; 1157 1158 1159 // A Handle-ized version of PreviousVersionNode. 1160 class PreviousVersionInfo : public ResourceObj { 1161 private: 1162 constantPoolHandle _prev_constant_pool_handle; 1163 // If the previous version of the InstanceKlass doesn't have any 1164 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the 1165 // methods cannot be collected while we hold a handle, 1166 // _prev_EMCP_methods should never have a length of zero. 1167 GrowableArray<methodHandle>* _prev_EMCP_method_handles; 1168 1169 public: 1170 PreviousVersionInfo(PreviousVersionNode *pv_node); 1171 ~PreviousVersionInfo(); 1172 constantPoolHandle prev_constant_pool_handle() const { 1173 return _prev_constant_pool_handle; 1174 } 1175 GrowableArray<methodHandle>* prev_EMCP_method_handles() const { 1176 return _prev_EMCP_method_handles; 1177 } 1178 }; 1179 1180 1181 // Helper object for walking previous versions. This helper cleans up 1182 // the Handles that it allocates when the helper object is destroyed. 1183 // The PreviousVersionInfo object returned by next_previous_version() 1184 // is only valid until a subsequent call to next_previous_version() or 1185 // the helper object is destroyed. 1186 class PreviousVersionWalker : public StackObj { 1187 private: 1188 GrowableArray<PreviousVersionNode *>* _previous_versions; 1189 int _current_index; 1190 // Fields for cleaning up when we are done walking the previous versions: 1191 // A HandleMark for the PreviousVersionInfo handles: 1192 HandleMark _hm; 1193 1194 // It would be nice to have a ResourceMark field in this helper also, 1195 // but the ResourceMark code says to be careful to delete handles held 1196 // in GrowableArrays _before_ deleting the GrowableArray. Since we 1197 // can't guarantee the order in which the fields are destroyed, we 1198 // have to let the creator of the PreviousVersionWalker object do 1199 // the right thing. Also, adding a ResourceMark here causes an 1200 // include loop. 1201 1202 // A pointer to the current info object so we can handle the deletes. 1203 PreviousVersionInfo * _current_p; 1204 1205 public: 1206 PreviousVersionWalker(InstanceKlass *ik); 1207 ~PreviousVersionWalker(); 1208 1209 // Return the interesting information for the next previous version 1210 // of the klass. Returns NULL if there are no more previous versions. 1211 PreviousVersionInfo* next_previous_version(); 1212 }; 1213 1214 1215 // 1216 // nmethodBucket is used to record dependent nmethods for 1217 // deoptimization. nmethod dependencies are actually <klass, method> 1218 // pairs but we really only care about the klass part for purposes of 1219 // finding nmethods which might need to be deoptimized. Instead of 1220 // recording the method, a count of how many times a particular nmethod 1221 // was recorded is kept. This ensures that any recording errors are 1222 // noticed since an nmethod should be removed as many times are it's 1223 // added. 1224 // 1225 class nmethodBucket: public CHeapObj<mtClass> { 1226 friend class VMStructs; 1227 private: 1228 nmethod* _nmethod; 1229 int _count; 1230 nmethodBucket* _next; 1231 1232 public: 1233 nmethodBucket(nmethod* nmethod, nmethodBucket* next) { 1234 _nmethod = nmethod; 1235 _next = next; 1236 _count = 1; 1237 } 1238 int count() { return _count; } 1239 int increment() { _count += 1; return _count; } 1240 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; } 1241 nmethodBucket* next() { return _next; } 1242 void set_next(nmethodBucket* b) { _next = b; } 1243 nmethod* get_nmethod() { return _nmethod; } 1244 }; 1245 1246 // An iterator that's used to access the inner classes indices in the 1247 // InstanceKlass::_inner_classes array. 1248 class InnerClassesIterator : public StackObj { 1249 private: 1250 Array<jushort>* _inner_classes; 1251 int _length; 1252 int _idx; 1253 public: 1254 1255 InnerClassesIterator(instanceKlassHandle k) { 1256 _inner_classes = k->inner_classes(); 1257 if (k->inner_classes() != NULL) { 1258 _length = _inner_classes->length(); 1259 // The inner class array's length should be the multiple of 1260 // inner_class_next_offset if it only contains the InnerClasses 1261 // attribute data, or it should be 1262 // n*inner_class_next_offset+enclosing_method_attribute_size 1263 // if it also contains the EnclosingMethod data. 1264 assert((_length % InstanceKlass::inner_class_next_offset == 0 || 1265 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size), 1266 "just checking"); 1267 // Remove the enclosing_method portion if exists. 1268 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) { 1269 _length -= InstanceKlass::enclosing_method_attribute_size; 1270 } 1271 } else { 1272 _length = 0; 1273 } 1274 _idx = 0; 1275 } 1276 1277 int length() const { 1278 return _length; 1279 } 1280 1281 void next() { 1282 _idx += InstanceKlass::inner_class_next_offset; 1283 } 1284 1285 bool done() const { 1286 return (_idx >= _length); 1287 } 1288 1289 u2 inner_class_info_index() const { 1290 return _inner_classes->at( 1291 _idx + InstanceKlass::inner_class_inner_class_info_offset); 1292 } 1293 1294 void set_inner_class_info_index(u2 index) { 1295 _inner_classes->at_put( 1296 _idx + InstanceKlass::inner_class_inner_class_info_offset, index); 1297 } 1298 1299 u2 outer_class_info_index() const { 1300 return _inner_classes->at( 1301 _idx + InstanceKlass::inner_class_outer_class_info_offset); 1302 } 1303 1304 void set_outer_class_info_index(u2 index) { 1305 _inner_classes->at_put( 1306 _idx + InstanceKlass::inner_class_outer_class_info_offset, index); 1307 } 1308 1309 u2 inner_name_index() const { 1310 return _inner_classes->at( 1311 _idx + InstanceKlass::inner_class_inner_name_offset); 1312 } 1313 1314 void set_inner_name_index(u2 index) { 1315 _inner_classes->at_put( 1316 _idx + InstanceKlass::inner_class_inner_name_offset, index); 1317 } 1318 1319 u2 inner_access_flags() const { 1320 return _inner_classes->at( 1321 _idx + InstanceKlass::inner_class_access_flags_offset); 1322 } 1323 }; 1324 1325 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP