instanceKlass.hpp revision 1879:f95d63e2154a
12337Scsgr/* 22337Scsgr * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. 32337Scsgr * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 42337Scsgr * 52337Scsgr * This code is free software; you can redistribute it and/or modify it 62337Scsgr * under the terms of the GNU General Public License version 2 only, as 72337Scsgr * published by the Free Software Foundation. 82337Scsgr * 92337Scsgr * This code is distributed in the hope that it will be useful, but WITHOUT 102337Scsgr * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 112337Scsgr * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 122337Scsgr * version 2 for more details (a copy is included in the LICENSE file that 132337Scsgr * accompanied this code). 142337Scsgr * 152337Scsgr * You should have received a copy of the GNU General Public License version 162337Scsgr * 2 along with this work; if not, write to the Free Software Foundation, 172337Scsgr * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 182337Scsgr * 192337Scsgr * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 202337Scsgr * or visit www.oracle.com if you need additional information or have any 212337Scsgr * questions. 222337Scsgr * 232337Scsgr */ 242337Scsgr 252337Scsgr#ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP 262337Scsgr#define SHARE_VM_OOPS_INSTANCEKLASS_HPP 272337Scsgr 282337Scsgr#include "oops/constMethodOop.hpp" 292337Scsgr#include "oops/constantPoolOop.hpp" 302337Scsgr#include "oops/instanceOop.hpp" 312337Scsgr#include "oops/klassOop.hpp" 322337Scsgr#include "oops/klassVtable.hpp" 332337Scsgr#include "oops/objArrayOop.hpp" 342337Scsgr#include "runtime/handles.hpp" 3531422Scharnier#include "runtime/os.hpp" 3650476Speter#include "utilities/accessFlags.hpp" 372337Scsgr#include "utilities/bitMap.inline.hpp" 382337Scsgr 3932312Scharnier// An instanceKlass is the VM level representation of a Java class. 4032312Scharnier// It contains all information needed for at class at execution runtime. 4132312Scharnier 422337Scsgr// instanceKlass layout: 4331422Scharnier// [header ] klassOop 4431422Scharnier// [klass pointer ] klassOop 452337Scsgr// [C++ vtbl pointer ] Klass 46115668Sobrien// [subtype cache ] Klass 4731422Scharnier// [instance size ] Klass 48202210Sed// [java mirror ] Klass 492337Scsgr// [super ] Klass 502337Scsgr// [access_flags ] Klass 512337Scsgr// [name ] Klass 522337Scsgr// [first subklass ] Klass 532337Scsgr// [next sibling ] Klass 542337Scsgr// [array klasses ] 552337Scsgr// [methods ] 56241777Sed// [local interfaces ] 57241777Sed// [transitive interfaces ] 582337Scsgr// [number of implementors ] 592337Scsgr// [implementors ] klassOop[2] 602337Scsgr// [fields ] 612337Scsgr// [constants ] 62201146Sed// [class loader ] 63201192Sed// [protection domain ] 64201192Sed// [signers ] 652337Scsgr// [source file name ] 662337Scsgr// [inner classes ] 67201146Sed// [static field size ] 682337Scsgr// [nonstatic field size ] 692337Scsgr// [static oop fields size ] 702337Scsgr// [nonstatic oop maps size ] 712337Scsgr// [has finalize method ] 7290336Simp// [deoptimization mark bit ] 732337Scsgr// [initialization state ] 742337Scsgr// [initializing thread ] 752337Scsgr// [Java vtable length ] 762337Scsgr// [oop map cache (stack maps) ] 772337Scsgr// [EMBEDDED Java vtable ] size in words = vtable_len 782337Scsgr// [EMBEDDED static oop fields ] size in words = static_oop_fields_size 79201146Sed// [ static non-oop fields ] size in words = static_field_size - static_oop_fields_size 80201146Sed// [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size 812337Scsgr// 82201146Sed// The embedded nonstatic oop-map blocks are short pairs (offset, length) indicating 83201146Sed// where oops are located in instances of this klass. 84201146Sed 85201146Sed 86201146Sed// forward declaration for class -- see below for definition 87201146Sedclass SuperTypeClosure; 88201146Sedclass JNIid; 89201146Sedclass jniIdMapBase; 90201146Sedclass BreakpointInfo; 91201146Sedclass fieldDescriptor; 92201146Sedclass DepChange; 93201146Sedclass nmethodBucket; 94201146Sedclass PreviousVersionNode; 95201146Sedclass JvmtiCachedClassFieldMap; 96201146Sed 97201146Sed// This is used in iterators below. 98201146Sedclass FieldClosure: public StackObj { 99201146Sedpublic: 100201146Sed virtual void do_field(fieldDescriptor* fd) = 0; 101201146Sed}; 102201146Sed 103201146Sed#ifndef PRODUCT 104201146Sed// Print fields. 1052337Scsgr// If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields. 106201146Sedclass FieldPrinter: public FieldClosure { 107201146Sed oop _obj; 1082337Scsgr outputStream* _st; 1092337Scsgr public: 1102337Scsgr FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {} 1112337Scsgr void do_field(fieldDescriptor* fd); 112201146Sed}; 1132337Scsgr#endif // !PRODUCT 114201146Sed 115201146Sed// ValueObjs embedded in klass. Describes where oops are located in instances of 116201146Sed// this klass. 117201146Sedclass OopMapBlock VALUE_OBJ_CLASS_SPEC { 1188870Srgrimes public: 119201146Sed // Byte offset of the first oop mapped by this block. 120201146Sed int offset() const { return _offset; } 121201146Sed void set_offset(int offset) { _offset = offset; } 122201146Sed 1232337Scsgr // Number of oops in this block. 124201146Sed uint count() const { return _count; } 125201146Sed void set_count(uint count) { _count = count; } 1262337Scsgr 127201146Sed // sizeof(OopMapBlock) in HeapWords. 128201146Sed static const int size_in_words() { 129201146Sed return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >> 1304131Sjkh LogHeapWordSize; 131201146Sed } 1322337Scsgr 133201146Sed private: 1342337Scsgr int _offset; 135201146Sed uint _count; 136201146Sed}; 137201146Sed 138201146Sedclass instanceKlass: public Klass { 139201146Sed friend class VMStructs; 1402337Scsgr public: 141201146Sed // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description 1422337Scsgr // of the class loading & initialization procedure, and the use of the states. 143201146Sed enum ClassState { 144201146Sed unparsable_by_gc = 0, // object is not yet parsable by gc. Value of _init_state at object allocation. 145201146Sed allocated, // allocated (but not yet linked) 1462337Scsgr loaded, // loaded and inserted in class hierarchy (but not linked yet) 147201146Sed linked, // successfully linked/verified (but not initialized yet) 148201146Sed being_initialized, // currently running class initializer 1492337Scsgr fully_initialized, // initialized (successfull final state) 150201146Sed initialization_error // error happened during initialization 151201146Sed }; 152201146Sed 1532337Scsgr public: 154201146Sed oop* oop_block_beg() const { return adr_array_klasses(); } 1552337Scsgr oop* oop_block_end() const { return adr_methods_default_annotations() + 1; } 1568870Srgrimes 1572337Scsgr enum { 158201146Sed implementors_limit = 2 // how many implems can we track? 1592337Scsgr }; 160201146Sed 161201192Sed protected: 162201146Sed // 1638870Srgrimes // The oop block. See comment in klass.hpp before making changes. 164201192Sed // 165201146Sed 1668870Srgrimes // Array classes holding elements of this class. 167201192Sed klassOop _array_klasses; 168201192Sed // Method array. 169201192Sed objArrayOop _methods; 170201192Sed // Int array containing the original order of method in the class file (for 1712337Scsgr // JVMTI). 172201192Sed typeArrayOop _method_ordering; 173201192Sed // Interface (klassOops) this class declares locally to implement. 174201192Sed objArrayOop _local_interfaces; 175201192Sed // Interface (klassOops) this class implements transitively. 176201192Sed objArrayOop _transitive_interfaces; 177201192Sed // Instance and static variable information, 5-tuples of shorts [access, name 178201192Sed // index, sig index, initval index, offset]. 179201192Sed typeArrayOop _fields; 180201192Sed // Constant pool for this class. 181201192Sed constantPoolOop _constants; 1828870Srgrimes // Class loader used to load this class, NULL if VM loader used. 183201192Sed oop _class_loader; 184201192Sed // Protection domain. 185201192Sed oop _protection_domain; 1862337Scsgr // Host class, which grants its access privileges to this class also. 187201146Sed // This is only non-null for an anonymous class (AnonymousClasses enabled). 188201146Sed // The host class is either named, or a previously loaded anonymous class. 1892337Scsgr klassOop _host_klass; 1902337Scsgr // Class signers. 191201146Sed objArrayOop _signers; 192201146Sed // Name of source file containing this klass, NULL if not specified. 1932337Scsgr symbolOop _source_file_name; 194201146Sed // the source debug extension for this klass, NULL if not specified. 195201192Sed symbolOop _source_debug_extension; 196201192Sed // inner_classes attribute. 197201192Sed typeArrayOop _inner_classes; 198201192Sed // Implementors of this interface (not valid if it overflows) 199201192Sed klassOop _implementors[implementors_limit]; 200201192Sed // Generic signature, or null if none. 201201192Sed symbolOop _generic_signature; 202201146Sed // invokedynamic bootstrap method (a java.dyn.MethodHandle) 203201192Sed oop _bootstrap_method; 204201192Sed // Annotations for this class, or null if none. 205201146Sed typeArrayOop _class_annotations; 2062337Scsgr // Annotation objects (byte arrays) for fields, or null if no annotations. 2072337Scsgr // Indices correspond to entries (not indices) in fields array. 2082337Scsgr objArrayOop _fields_annotations; 209201146Sed // Annotation objects (byte arrays) for methods, or null if no annotations. 2102337Scsgr // Index is the idnum, which is initially the same as the methods array index. 211201146Sed objArrayOop _methods_annotations; 212201146Sed // Annotation objects (byte arrays) for methods' parameters, or null if no 213201146Sed // such annotations. 2148870Srgrimes // Index is the idnum, which is initially the same as the methods array index. 215201146Sed objArrayOop _methods_parameter_annotations; 2168870Srgrimes // Annotation objects (byte arrays) for methods' default values, or null if no 217201146Sed // such annotations. 218201146Sed // Index is the idnum, which is initially the same as the methods array index. 219201146Sed objArrayOop _methods_default_annotations; 220201146Sed 221201146Sed // 222201146Sed // End of the oop block. 223201146Sed // 2248870Srgrimes 225201146Sed // Number of heapOopSize words used by non-static fields in this klass 2268870Srgrimes // (including inherited fields but after header_size()). 227201146Sed int _nonstatic_field_size; 2282337Scsgr int _static_field_size; // number words used by static fields (oop and non-oop) in this klass 2292337Scsgr int _static_oop_field_size;// number of static oop fields in this klass 2302337Scsgr int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks 231201146Sed bool _is_marked_dependent; // used for marking during flushing and deoptimization 2322337Scsgr bool _rewritten; // methods rewritten. 233201146Sed bool _has_nonstatic_fields; // for sizing with UseCompressedOops 234201146Sed bool _should_verify_class; // allow caching of preverification 2352337Scsgr u2 _minor_version; // minor version number of class file 2362337Scsgr u2 _major_version; // major version number of class file 2372337Scsgr ClassState _init_state; // state of class 238201146Sed Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization) 2392337Scsgr int _vtable_len; // length of Java vtable (in words) 240201146Sed int _itable_len; // length of Java itable (in words) 241201146Sed ReferenceType _reference_type; // reference type 2422337Scsgr OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily) 2432337Scsgr JNIid* _jni_ids; // First JNI identifier for static fields in this class 2442337Scsgr jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none 245201146Sed int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL 2462337Scsgr nmethodBucket* _dependencies; // list of dependent nmethods 247201146Sed nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class 248201146Sed BreakpointInfo* _breakpoints; // bpt lists, managed by methodOop 2492337Scsgr int _nof_implementors; // No of implementors of this interface (zero if not an interface) 2502337Scsgr // Array of interesting part(s) of the previous version(s) of this 2512337Scsgr // instanceKlass. See PreviousVersionWalker below. 252201146Sed GrowableArray<PreviousVersionNode *>* _previous_versions; 2532337Scsgr u2 _enclosing_method_class_index; // Constant pool index for class of enclosing method, or 0 if none 254201146Sed u2 _enclosing_method_method_index; // Constant pool index for name and type of enclosing method, or 0 if none 255201146Sed // JVMTI fields can be moved to their own structure - see 6315920 2562337Scsgr unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH 2572337Scsgr jint _cached_class_file_len; // JVMTI: length of above 258201146Sed JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration 259201146Sed volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change 2602337Scsgr 26190336Simp // embedded Java vtable follows here 2622337Scsgr // embedded Java itables follows here 2632337Scsgr // embedded static fields follows here 2642337Scsgr // embedded nonstatic oop-map blocks follows here 2652337Scsgr 2662337Scsgr friend class instanceKlassKlass; 267201146Sed friend class SystemDictionary; 268201146Sed 2692337Scsgr public: 2702337Scsgr bool has_nonstatic_fields() const { return _has_nonstatic_fields; } 2712337Scsgr void set_has_nonstatic_fields(bool b) { _has_nonstatic_fields = b; } 27295658Sdes 2732337Scsgr // field sizes 2742337Scsgr int nonstatic_field_size() const { return _nonstatic_field_size; } 2752337Scsgr void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; } 276201146Sed 277201146Sed int static_field_size() const { return _static_field_size; } 278201146Sed void set_static_field_size(int size) { _static_field_size = size; } 2792337Scsgr 2802337Scsgr int static_oop_field_size() const { return _static_oop_field_size; } 2812337Scsgr void set_static_oop_field_size(int size) { _static_oop_field_size = size; } 282201146Sed 283201146Sed // Java vtable 284201146Sed int vtable_length() const { return _vtable_len; } 285201146Sed void set_vtable_length(int len) { _vtable_len = len; } 286201146Sed 287201146Sed // Java itable 288201146Sed int itable_length() const { return _itable_len; } 289201146Sed void set_itable_length(int len) { _itable_len = len; } 290201146Sed 291201146Sed // array klasses 292201146Sed klassOop array_klasses() const { return _array_klasses; } 293201146Sed void set_array_klasses(klassOop k) { oop_store_without_check((oop*) &_array_klasses, (oop) k); } 294201146Sed 295201146Sed // methods 2962337Scsgr objArrayOop methods() const { return _methods; } 2972337Scsgr void set_methods(objArrayOop a) { oop_store_without_check((oop*) &_methods, (oop) a); } 2982337Scsgr methodOop method_with_idnum(int idnum); 299201146Sed 300201146Sed // method ordering 301201146Sed typeArrayOop method_ordering() const { return _method_ordering; } 302201146Sed void set_method_ordering(typeArrayOop m) { oop_store_without_check((oop*) &_method_ordering, (oop) m); } 303201146Sed 304201146Sed // interfaces 305201146Sed objArrayOop local_interfaces() const { return _local_interfaces; } 306201146Sed void set_local_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_local_interfaces, (oop) a); } 307201146Sed objArrayOop transitive_interfaces() const { return _transitive_interfaces; } 308201146Sed void set_transitive_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_transitive_interfaces, (oop) a); } 309201146Sed 310201146Sed // fields 311201146Sed // Field info extracted from the class file and stored 312201146Sed // as an array of 7 shorts 3132337Scsgr enum FieldOffset { 3142337Scsgr access_flags_offset = 0, 3152337Scsgr name_index_offset = 1, 3162337Scsgr signature_index_offset = 2, 3172337Scsgr initval_index_offset = 3, 3182337Scsgr low_offset = 4, 31995658Sdes high_offset = 5, 32095658Sdes generic_signature_offset = 6, 3212337Scsgr next_offset = 7 3222337Scsgr }; 3232337Scsgr 3242337Scsgr typeArrayOop fields() const { return _fields; } 32595658Sdes int offset_from_fields( int index ) const { 32695658Sdes return build_int_from_shorts( fields()->ushort_at(index + low_offset), 3272337Scsgr fields()->ushort_at(index + high_offset) ); 3282337Scsgr } 32995658Sdes 33032312Scharnier void set_fields(typeArrayOop f) { oop_store_without_check((oop*) &_fields, (oop) f); } 33132312Scharnier 33232312Scharnier // inner classes 3332337Scsgr typeArrayOop inner_classes() const { return _inner_classes; } 334201146Sed void set_inner_classes(typeArrayOop f) { oop_store_without_check((oop*) &_inner_classes, (oop) f); } 335201146Sed 3362337Scsgr enum InnerClassAttributeOffset { 337 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814 338 inner_class_inner_class_info_offset = 0, 339 inner_class_outer_class_info_offset = 1, 340 inner_class_inner_name_offset = 2, 341 inner_class_access_flags_offset = 3, 342 inner_class_next_offset = 4 343 }; 344 345 // method override check 346 bool is_override(methodHandle super_method, Handle targetclassloader, symbolHandle targetclassname, TRAPS); 347 348 // package 349 bool is_same_class_package(klassOop class2); 350 bool is_same_class_package(oop classloader2, symbolOop classname2); 351 static bool is_same_class_package(oop class_loader1, symbolOop class_name1, oop class_loader2, symbolOop class_name2); 352 353 // find an enclosing class (defined where original code was, in jvm.cpp!) 354 klassOop compute_enclosing_class(bool* inner_is_member, TRAPS) { 355 instanceKlassHandle self(THREAD, this->as_klassOop()); 356 return compute_enclosing_class_impl(self, inner_is_member, THREAD); 357 } 358 static klassOop compute_enclosing_class_impl(instanceKlassHandle self, 359 bool* inner_is_member, TRAPS); 360 361 // tell if two classes have the same enclosing class (at package level) 362 bool is_same_package_member(klassOop class2, TRAPS) { 363 instanceKlassHandle self(THREAD, this->as_klassOop()); 364 return is_same_package_member_impl(self, class2, THREAD); 365 } 366 static bool is_same_package_member_impl(instanceKlassHandle self, 367 klassOop class2, TRAPS); 368 369 // initialization state 370 bool is_loaded() const { return _init_state >= loaded; } 371 bool is_linked() const { return _init_state >= linked; } 372 bool is_initialized() const { return _init_state == fully_initialized; } 373 bool is_not_initialized() const { return _init_state < being_initialized; } 374 bool is_being_initialized() const { return _init_state == being_initialized; } 375 bool is_in_error_state() const { return _init_state == initialization_error; } 376 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; } 377 int get_init_state() { return _init_state; } // Useful for debugging 378 bool is_rewritten() const { return _rewritten; } 379 380 // defineClass specified verification 381 bool should_verify_class() const { return _should_verify_class; } 382 void set_should_verify_class(bool value) { _should_verify_class = value; } 383 384 // marking 385 bool is_marked_dependent() const { return _is_marked_dependent; } 386 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; } 387 388 // initialization (virtuals from Klass) 389 bool should_be_initialized() const; // means that initialize should be called 390 void initialize(TRAPS); 391 void link_class(TRAPS); 392 bool link_class_or_fail(TRAPS); // returns false on failure 393 void unlink_class(); 394 void rewrite_class(TRAPS); 395 methodOop class_initializer(); 396 397 // set the class to initialized if no static initializer is present 398 void eager_initialize(Thread *thread); 399 400 // reference type 401 ReferenceType reference_type() const { return _reference_type; } 402 void set_reference_type(ReferenceType t) { _reference_type = t; } 403 404 // find local field, returns true if found 405 bool find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; 406 // find field in direct superinterfaces, returns the interface in which the field is defined 407 klassOop find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; 408 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined 409 klassOop find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; 410 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined 411 klassOop find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const; 412 413 // find a non-static or static field given its offset within the class. 414 bool contains_field_offset(int offset) { 415 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size()); 416 } 417 418 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; 419 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; 420 421 // find a local method (returns NULL if not found) 422 methodOop find_method(symbolOop name, symbolOop signature) const; 423 static methodOop find_method(objArrayOop methods, symbolOop name, symbolOop signature); 424 425 // lookup operation (returns NULL if not found) 426 methodOop uncached_lookup_method(symbolOop name, symbolOop signature) const; 427 428 // lookup a method in all the interfaces that this class implements 429 // (returns NULL if not found) 430 methodOop lookup_method_in_all_interfaces(symbolOop name, symbolOop signature) const; 431 432 // constant pool 433 constantPoolOop constants() const { return _constants; } 434 void set_constants(constantPoolOop c) { oop_store_without_check((oop*) &_constants, (oop) c); } 435 436 // class loader 437 oop class_loader() const { return _class_loader; } 438 void set_class_loader(oop l) { oop_store((oop*) &_class_loader, l); } 439 440 // protection domain 441 oop protection_domain() { return _protection_domain; } 442 void set_protection_domain(oop pd) { oop_store((oop*) &_protection_domain, pd); } 443 444 // host class 445 oop host_klass() const { return _host_klass; } 446 void set_host_klass(oop host) { oop_store((oop*) &_host_klass, host); } 447 bool is_anonymous() const { return _host_klass != NULL; } 448 449 // signers 450 objArrayOop signers() const { return _signers; } 451 void set_signers(objArrayOop s) { oop_store((oop*) &_signers, oop(s)); } 452 453 // source file name 454 symbolOop source_file_name() const { return _source_file_name; } 455 void set_source_file_name(symbolOop n) { oop_store_without_check((oop*) &_source_file_name, (oop) n); } 456 457 // minor and major version numbers of class file 458 u2 minor_version() const { return _minor_version; } 459 void set_minor_version(u2 minor_version) { _minor_version = minor_version; } 460 u2 major_version() const { return _major_version; } 461 void set_major_version(u2 major_version) { _major_version = major_version; } 462 463 // source debug extension 464 symbolOop source_debug_extension() const { return _source_debug_extension; } 465 void set_source_debug_extension(symbolOop n){ oop_store_without_check((oop*) &_source_debug_extension, (oop) n); } 466 467 // nonstatic oop-map blocks 468 static int nonstatic_oop_map_size(unsigned int oop_map_count) { 469 return oop_map_count * OopMapBlock::size_in_words(); 470 } 471 unsigned int nonstatic_oop_map_count() const { 472 return _nonstatic_oop_map_size / OopMapBlock::size_in_words(); 473 } 474 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; } 475 void set_nonstatic_oop_map_size(int words) { 476 _nonstatic_oop_map_size = words; 477 } 478 479 // RedefineClasses() support for previous versions: 480 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods, 481 int emcp_method_count); 482 // If the _previous_versions array is non-NULL, then this klass 483 // has been redefined at least once even if we aren't currently 484 // tracking a previous version. 485 bool has_been_redefined() const { return _previous_versions != NULL; } 486 bool has_previous_version() const; 487 void init_previous_versions() { 488 _previous_versions = NULL; 489 } 490 GrowableArray<PreviousVersionNode *>* previous_versions() const { 491 return _previous_versions; 492 } 493 494 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation 495 void set_cached_class_file(unsigned char *class_file_bytes, 496 jint class_file_len) { _cached_class_file_len = class_file_len; 497 _cached_class_file_bytes = class_file_bytes; } 498 jint get_cached_class_file_len() { return _cached_class_file_len; } 499 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; } 500 501 // JVMTI: Support for caching of field indices, types, and offsets 502 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) { 503 _jvmti_cached_class_field_map = descriptor; 504 } 505 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const { 506 return _jvmti_cached_class_field_map; 507 } 508 509 // for adding methods, constMethodOopDesc::UNSET_IDNUM means no more ids available 510 inline u2 next_method_idnum(); 511 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; } 512 513 // generics support 514 symbolOop generic_signature() const { return _generic_signature; } 515 void set_generic_signature(symbolOop sig) { oop_store_without_check((oop*)&_generic_signature, (oop)sig); } 516 u2 enclosing_method_class_index() const { return _enclosing_method_class_index; } 517 u2 enclosing_method_method_index() const { return _enclosing_method_method_index; } 518 void set_enclosing_method_indices(u2 class_index, 519 u2 method_index) { _enclosing_method_class_index = class_index; 520 _enclosing_method_method_index = method_index; } 521 522 // JSR 292 support 523 oop bootstrap_method() const { return _bootstrap_method; } 524 void set_bootstrap_method(oop mh) { oop_store(&_bootstrap_method, mh); } 525 526 // jmethodID support 527 static jmethodID get_jmethod_id(instanceKlassHandle ik_h, 528 methodHandle method_h); 529 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h, 530 size_t idnum, jmethodID new_id, jmethodID* new_jmeths, 531 jmethodID* to_dealloc_id_p, 532 jmethodID** to_dealloc_jmeths_p); 533 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum, 534 size_t *length_p, jmethodID* id_p); 535 jmethodID jmethod_id_or_null(methodOop method); 536 537 // cached itable index support 538 void set_cached_itable_index(size_t idnum, int index); 539 int cached_itable_index(size_t idnum); 540 541 // annotations support 542 typeArrayOop class_annotations() const { return _class_annotations; } 543 objArrayOop fields_annotations() const { return _fields_annotations; } 544 objArrayOop methods_annotations() const { return _methods_annotations; } 545 objArrayOop methods_parameter_annotations() const { return _methods_parameter_annotations; } 546 objArrayOop methods_default_annotations() const { return _methods_default_annotations; } 547 void set_class_annotations(typeArrayOop md) { oop_store_without_check((oop*)&_class_annotations, (oop)md); } 548 void set_fields_annotations(objArrayOop md) { set_annotations(md, &_fields_annotations); } 549 void set_methods_annotations(objArrayOop md) { set_annotations(md, &_methods_annotations); } 550 void set_methods_parameter_annotations(objArrayOop md) { set_annotations(md, &_methods_parameter_annotations); } 551 void set_methods_default_annotations(objArrayOop md) { set_annotations(md, &_methods_default_annotations); } 552 typeArrayOop get_method_annotations_of(int idnum) 553 { return get_method_annotations_from(idnum, _methods_annotations); } 554 typeArrayOop get_method_parameter_annotations_of(int idnum) 555 { return get_method_annotations_from(idnum, _methods_parameter_annotations); } 556 typeArrayOop get_method_default_annotations_of(int idnum) 557 { return get_method_annotations_from(idnum, _methods_default_annotations); } 558 void set_method_annotations_of(int idnum, typeArrayOop anno) 559 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } 560 void set_method_parameter_annotations_of(int idnum, typeArrayOop anno) 561 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } 562 void set_method_default_annotations_of(int idnum, typeArrayOop anno) 563 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } 564 565 // allocation 566 DEFINE_ALLOCATE_PERMANENT(instanceKlass); 567 instanceOop allocate_instance(TRAPS); 568 instanceOop allocate_permanent_instance(TRAPS); 569 570 // additional member function to return a handle 571 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); } 572 573 objArrayOop allocate_objArray(int n, int length, TRAPS); 574 // Helper function 575 static instanceOop register_finalizer(instanceOop i, TRAPS); 576 577 // Check whether reflection/jni/jvm code is allowed to instantiate this class; 578 // if not, throw either an Error or an Exception. 579 virtual void check_valid_for_instantiation(bool throwError, TRAPS); 580 581 // initialization 582 void call_class_initializer(TRAPS); 583 void set_initialization_state_and_notify(ClassState state, TRAPS); 584 585 // OopMapCache support 586 OopMapCache* oop_map_cache() { return _oop_map_cache; } 587 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; } 588 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry); 589 590 // JNI identifier support (for static fields - for jni performance) 591 JNIid* jni_ids() { return _jni_ids; } 592 void set_jni_ids(JNIid* ids) { _jni_ids = ids; } 593 JNIid* jni_id_for(int offset); 594 595 // maintenance of deoptimization dependencies 596 int mark_dependent_nmethods(DepChange& changes); 597 void add_dependent_nmethod(nmethod* nm); 598 void remove_dependent_nmethod(nmethod* nm); 599 600 // On-stack replacement support 601 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; }; 602 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; }; 603 void add_osr_nmethod(nmethod* n); 604 void remove_osr_nmethod(nmethod* n); 605 nmethod* lookup_osr_nmethod(const methodOop m, int bci, int level, bool match_level) const; 606 607 // Breakpoint support (see methods on methodOop for details) 608 BreakpointInfo* breakpoints() const { return _breakpoints; }; 609 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; }; 610 611 // support for stub routines 612 static int init_state_offset_in_bytes() { return offset_of(instanceKlass, _init_state); } 613 static int init_thread_offset_in_bytes() { return offset_of(instanceKlass, _init_thread); } 614 615 // subclass/subinterface checks 616 bool implements_interface(klassOop k) const; 617 618 // Access to implementors of an interface. We only store the count 619 // of implementors, and in case, there are only a few 620 // implementors, we store them in a short list. 621 // This accessor returns NULL if we walk off the end of the list. 622 klassOop implementor(int i) const { 623 return (i < implementors_limit)? _implementors[i]: (klassOop) NULL; 624 } 625 int nof_implementors() const { return _nof_implementors; } 626 void add_implementor(klassOop k); // k is a new class that implements this interface 627 void init_implementor(); // initialize 628 629 // link this class into the implementors list of every interface it implements 630 void process_interfaces(Thread *thread); 631 632 // virtual operations from Klass 633 bool is_leaf_class() const { return _subklass == NULL; } 634 objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS); 635 bool compute_is_subtype_of(klassOop k); 636 bool can_be_primary_super_slow() const; 637 klassOop java_super() const { return super(); } 638 int oop_size(oop obj) const { return size_helper(); } 639 int klass_oop_size() const { return object_size(); } 640 bool oop_is_instance_slow() const { return true; } 641 642 // Iterators 643 void do_local_static_fields(FieldClosure* cl); 644 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields 645 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS); 646 647 void methods_do(void f(methodOop method)); 648 void array_klasses_do(void f(klassOop k)); 649 void with_array_klasses_do(void f(klassOop k)); 650 bool super_types_do(SuperTypeClosure* blk); 651 652 // Casting from klassOop 653 static instanceKlass* cast(klassOop k) { 654 Klass* kp = k->klass_part(); 655 assert(kp->null_vtbl() || kp->oop_is_instance_slow(), "cast to instanceKlass"); 656 return (instanceKlass*) kp; 657 } 658 659 // Sizing (in words) 660 static int header_size() { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); } 661 int object_size() const { return object_size(align_object_offset(vtable_length()) + align_object_offset(itable_length()) + static_field_size() + nonstatic_oop_map_size()); } 662 static int vtable_start_offset() { return header_size(); } 663 static int vtable_length_offset() { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; } 664 static int object_size(int extra) { return align_object_size(header_size() + extra); } 665 666 intptr_t* start_of_vtable() const { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); } 667 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); } 668 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)as_klassOop(); } 669 670 // Static field offset is an offset into the Heap, should be converted by 671 // based on UseCompressedOop for traversal 672 HeapWord* start_of_static_fields() const { 673 return (HeapWord*)(start_of_itable() + align_object_offset(itable_length())); 674 } 675 676 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); } 677 678 int offset_of_static_fields() const { 679 return (intptr_t)start_of_static_fields() - (intptr_t)as_klassOop(); 680 } 681 682 OopMapBlock* start_of_nonstatic_oop_maps() const { 683 return (OopMapBlock*) (start_of_static_fields() + static_field_size()); 684 } 685 686 // Allocation profiling support 687 juint alloc_size() const { return _alloc_count * size_helper(); } 688 void set_alloc_size(juint n) {} 689 690 // Use this to return the size of an instance in heap words: 691 int size_helper() const { 692 return layout_helper_to_size_helper(layout_helper()); 693 } 694 695 // This bit is initialized in classFileParser.cpp. 696 // It is false under any of the following conditions: 697 // - the class is abstract (including any interface) 698 // - the class has a finalizer (if !RegisterFinalizersAtInit) 699 // - the class size is larger than FastAllocateSizeLimit 700 // - the class is java/lang/Class, which cannot be allocated directly 701 bool can_be_fastpath_allocated() const { 702 return !layout_helper_needs_slow_path(layout_helper()); 703 } 704 705 // Java vtable/itable 706 klassVtable* vtable() const; // return new klassVtable wrapper 707 inline methodOop method_at_vtable(int index); 708 klassItable* itable() const; // return new klassItable wrapper 709 methodOop method_at_itable(klassOop holder, int index, TRAPS); 710 711 // Garbage collection 712 void oop_follow_contents(oop obj); 713 void follow_static_fields(); 714 void adjust_static_fields(); 715 int oop_adjust_pointers(oop obj); 716 bool object_is_parsable() const { return _init_state != unparsable_by_gc; } 717 // Value of _init_state must be zero (unparsable_by_gc) when klass field is set. 718 719 void follow_weak_klass_links( 720 BoolObjectClosure* is_alive, OopClosure* keep_alive); 721 void release_C_heap_structures(); 722 723 // Parallel Scavenge and Parallel Old 724 PARALLEL_GC_DECLS 725 726#ifndef SERIALGC 727 // Parallel Scavenge 728 void push_static_fields(PSPromotionManager* pm); 729 730 // Parallel Old 731 void follow_static_fields(ParCompactionManager* cm); 732 void copy_static_fields(ParCompactionManager* cm); 733 void update_static_fields(); 734 void update_static_fields(HeapWord* beg_addr, HeapWord* end_addr); 735#endif // SERIALGC 736 737 // Naming 738 const char* signature_name() const; 739 740 // Iterators 741 int oop_oop_iterate(oop obj, OopClosure* blk) { 742 return oop_oop_iterate_v(obj, blk); 743 } 744 745 int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) { 746 return oop_oop_iterate_v_m(obj, blk, mr); 747 } 748 749#define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \ 750 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \ 751 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \ 752 MemRegion mr); 753 754 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL) 755 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL) 756 757#ifndef SERIALGC 758#define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \ 759 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk); 760 761 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL) 762 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL) 763#endif // !SERIALGC 764 765 void iterate_static_fields(OopClosure* closure); 766 void iterate_static_fields(OopClosure* closure, MemRegion mr); 767 768private: 769 // initialization state 770#ifdef ASSERT 771 void set_init_state(ClassState state); 772#else 773 void set_init_state(ClassState state) { _init_state = state; } 774#endif 775 void set_rewritten() { _rewritten = true; } 776 void set_init_thread(Thread *thread) { _init_thread = thread; } 777 778 u2 idnum_allocated_count() const { return _idnum_allocated_count; } 779 // The RedefineClasses() API can cause new method idnums to be needed 780 // which will cause the caches to grow. Safety requires different 781 // cache management logic if the caches can grow instead of just 782 // going from NULL to non-NULL. 783 bool idnum_can_increment() const { return has_been_redefined(); } 784 jmethodID* methods_jmethod_ids_acquire() const 785 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); } 786 void release_set_methods_jmethod_ids(jmethodID* jmeths) 787 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); } 788 789 int* methods_cached_itable_indices_acquire() const 790 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); } 791 void release_set_methods_cached_itable_indices(int* indices) 792 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); } 793 794 inline typeArrayOop get_method_annotations_from(int idnum, objArrayOop annos); 795 void set_annotations(objArrayOop md, objArrayOop* md_p) { oop_store_without_check((oop*)md_p, (oop)md); } 796 void set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p); 797 798 // Offsets for memory management 799 oop* adr_array_klasses() const { return (oop*)&this->_array_klasses;} 800 oop* adr_methods() const { return (oop*)&this->_methods;} 801 oop* adr_method_ordering() const { return (oop*)&this->_method_ordering;} 802 oop* adr_local_interfaces() const { return (oop*)&this->_local_interfaces;} 803 oop* adr_transitive_interfaces() const { return (oop*)&this->_transitive_interfaces;} 804 oop* adr_fields() const { return (oop*)&this->_fields;} 805 oop* adr_constants() const { return (oop*)&this->_constants;} 806 oop* adr_class_loader() const { return (oop*)&this->_class_loader;} 807 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;} 808 oop* adr_host_klass() const { return (oop*)&this->_host_klass;} 809 oop* adr_signers() const { return (oop*)&this->_signers;} 810 oop* adr_source_file_name() const { return (oop*)&this->_source_file_name;} 811 oop* adr_source_debug_extension() const { return (oop*)&this->_source_debug_extension;} 812 oop* adr_inner_classes() const { return (oop*)&this->_inner_classes;} 813 oop* adr_implementors() const { return (oop*)&this->_implementors[0];} 814 oop* adr_generic_signature() const { return (oop*)&this->_generic_signature;} 815 oop* adr_bootstrap_method() const { return (oop*)&this->_bootstrap_method;} 816 oop* adr_methods_jmethod_ids() const { return (oop*)&this->_methods_jmethod_ids;} 817 oop* adr_methods_cached_itable_indices() const { return (oop*)&this->_methods_cached_itable_indices;} 818 oop* adr_class_annotations() const { return (oop*)&this->_class_annotations;} 819 oop* adr_fields_annotations() const { return (oop*)&this->_fields_annotations;} 820 oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;} 821 oop* adr_methods_parameter_annotations() const { return (oop*)&this->_methods_parameter_annotations;} 822 oop* adr_methods_default_annotations() const { return (oop*)&this->_methods_default_annotations;} 823 824 // Static methods that are used to implement member methods where an exposed this pointer 825 // is needed due to possible GCs 826 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); 827 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); 828 static void initialize_impl (instanceKlassHandle this_oop, TRAPS); 829 static void eager_initialize_impl (instanceKlassHandle this_oop); 830 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS); 831 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS); 832 static klassOop array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS); 833 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS); 834 /* jni_id_for_impl for jfieldID only */ 835 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset); 836 837 // Returns the array class for the n'th dimension 838 klassOop array_klass_impl(bool or_null, int n, TRAPS); 839 840 // Returns the array class with this class as element type 841 klassOop array_klass_impl(bool or_null, TRAPS); 842 843public: 844 // sharing support 845 virtual void remove_unshareable_info(); 846 void field_names_and_sigs_iterate(OopClosure* closure); 847 848 // jvm support 849 jint compute_modifier_flags(TRAPS) const; 850 851public: 852 // JVMTI support 853 jint jvmti_class_status() const; 854 855 public: 856 // Printing 857 void oop_print_value_on(oop obj, outputStream* st); 858#ifndef PRODUCT 859 void oop_print_on (oop obj, outputStream* st); 860 861 void print_dependent_nmethods(bool verbose = false); 862 bool is_dependent_nmethod(nmethod* nm); 863#endif 864 865 // Verification 866 const char* internal_name() const; 867 void oop_verify_on(oop obj, outputStream* st); 868 869#ifndef PRODUCT 870 static void verify_class_klass_nonstatic_oop_maps(klassOop k) PRODUCT_RETURN; 871#endif 872}; 873 874inline methodOop instanceKlass::method_at_vtable(int index) { 875#ifndef PRODUCT 876 assert(index >= 0, "valid vtable index"); 877 if (DebugVtables) { 878 verify_vtable_index(index); 879 } 880#endif 881 vtableEntry* ve = (vtableEntry*)start_of_vtable(); 882 return ve[index].method(); 883} 884 885inline typeArrayOop instanceKlass::get_method_annotations_from(int idnum, objArrayOop annos) { 886 if (annos == NULL || annos->length() <= idnum) { 887 return NULL; 888 } 889 return typeArrayOop(annos->obj_at(idnum)); 890} 891 892// for adding methods 893// UNSET_IDNUM return means no more ids available 894inline u2 instanceKlass::next_method_idnum() { 895 if (_idnum_allocated_count == constMethodOopDesc::MAX_IDNUM) { 896 return constMethodOopDesc::UNSET_IDNUM; // no more ids available 897 } else { 898 return _idnum_allocated_count++; 899 } 900} 901 902 903/* JNIid class for jfieldIDs only */ 904class JNIid: public CHeapObj { 905 friend class VMStructs; 906 private: 907 klassOop _holder; 908 JNIid* _next; 909 int _offset; 910#ifdef ASSERT 911 bool _is_static_field_id; 912#endif 913 914 public: 915 // Accessors 916 klassOop holder() const { return _holder; } 917 int offset() const { return _offset; } 918 JNIid* next() { return _next; } 919 // Constructor 920 JNIid(klassOop holder, int offset, JNIid* next); 921 // Identifier lookup 922 JNIid* find(int offset); 923 924 // Garbage collection support 925 oop* holder_addr() { return (oop*)&_holder; } 926 void oops_do(OopClosure* f); 927 static void deallocate(JNIid* id); 928 // Debugging 929#ifdef ASSERT 930 bool is_static_field_id() const { return _is_static_field_id; } 931 void set_is_static_field_id() { _is_static_field_id = true; } 932#endif 933 void verify(klassOop holder); 934}; 935 936 937// If breakpoints are more numerous than just JVMTI breakpoints, 938// consider compressing this data structure. 939// It is currently a simple linked list defined in methodOop.hpp. 940 941class BreakpointInfo; 942 943 944// A collection point for interesting information about the previous 945// version(s) of an instanceKlass. This class uses weak references to 946// the information so that the information may be collected as needed 947// by the system. If the information is shared, then a regular 948// reference must be used because a weak reference would be seen as 949// collectible. A GrowableArray of PreviousVersionNodes is attached 950// to the instanceKlass as needed. See PreviousVersionWalker below. 951class PreviousVersionNode : public CHeapObj { 952 private: 953 // A shared ConstantPool is never collected so we'll always have 954 // a reference to it so we can update items in the cache. We'll 955 // have a weak reference to a non-shared ConstantPool until all 956 // of the methods (EMCP or obsolete) have been collected; the 957 // non-shared ConstantPool becomes collectible at that point. 958 jobject _prev_constant_pool; // regular or weak reference 959 bool _prev_cp_is_weak; // true if not a shared ConstantPool 960 961 // If the previous version of the instanceKlass doesn't have any 962 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the 963 // EMCP methods have been collected, then _prev_EMCP_methods can 964 // have a length of zero. 965 GrowableArray<jweak>* _prev_EMCP_methods; 966 967public: 968 PreviousVersionNode(jobject prev_constant_pool, bool prev_cp_is_weak, 969 GrowableArray<jweak>* prev_EMCP_methods); 970 ~PreviousVersionNode(); 971 jobject prev_constant_pool() const { 972 return _prev_constant_pool; 973 } 974 GrowableArray<jweak>* prev_EMCP_methods() const { 975 return _prev_EMCP_methods; 976 } 977}; 978 979 980// A Handle-ized version of PreviousVersionNode. 981class PreviousVersionInfo : public ResourceObj { 982 private: 983 constantPoolHandle _prev_constant_pool_handle; 984 // If the previous version of the instanceKlass doesn't have any 985 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the 986 // methods cannot be collected while we hold a handle, 987 // _prev_EMCP_methods should never have a length of zero. 988 GrowableArray<methodHandle>* _prev_EMCP_method_handles; 989 990public: 991 PreviousVersionInfo(PreviousVersionNode *pv_node); 992 ~PreviousVersionInfo(); 993 constantPoolHandle prev_constant_pool_handle() const { 994 return _prev_constant_pool_handle; 995 } 996 GrowableArray<methodHandle>* prev_EMCP_method_handles() const { 997 return _prev_EMCP_method_handles; 998 } 999}; 1000 1001 1002// Helper object for walking previous versions. This helper cleans up 1003// the Handles that it allocates when the helper object is destroyed. 1004// The PreviousVersionInfo object returned by next_previous_version() 1005// is only valid until a subsequent call to next_previous_version() or 1006// the helper object is destroyed. 1007class PreviousVersionWalker : public StackObj { 1008 private: 1009 GrowableArray<PreviousVersionNode *>* _previous_versions; 1010 int _current_index; 1011 // Fields for cleaning up when we are done walking the previous versions: 1012 // A HandleMark for the PreviousVersionInfo handles: 1013 HandleMark _hm; 1014 1015 // It would be nice to have a ResourceMark field in this helper also, 1016 // but the ResourceMark code says to be careful to delete handles held 1017 // in GrowableArrays _before_ deleting the GrowableArray. Since we 1018 // can't guarantee the order in which the fields are destroyed, we 1019 // have to let the creator of the PreviousVersionWalker object do 1020 // the right thing. Also, adding a ResourceMark here causes an 1021 // include loop. 1022 1023 // A pointer to the current info object so we can handle the deletes. 1024 PreviousVersionInfo * _current_p; 1025 1026 public: 1027 PreviousVersionWalker(instanceKlass *ik); 1028 ~PreviousVersionWalker(); 1029 1030 // Return the interesting information for the next previous version 1031 // of the klass. Returns NULL if there are no more previous versions. 1032 PreviousVersionInfo* next_previous_version(); 1033}; 1034 1035#endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP 1036