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 "memory/referenceType.hpp"
30 #include "oops/annotations.hpp"
31 #include "oops/constMethod.hpp"
32 #include "oops/fieldInfo.hpp"
33 #include "oops/instanceOop.hpp"
34 #include "oops/klassVtable.hpp"
35 #include "runtime/atomic.hpp"
36 #include "runtime/handles.hpp"
37 #include "runtime/os.hpp"
38 #include "utilities/accessFlags.hpp"
39 #include "utilities/bitMap.inline.hpp"
40 #include "utilities/macros.hpp"
41 #include "trace/traceMacros.hpp"
42
43 // An InstanceKlass is the VM level representation of a Java class.
44 // It contains all information needed for at class at execution runtime.
45
46 // InstanceKlass layout:
47 // [C++ vtbl pointer ] Klass
48 // [subtype cache ] Klass
49 // [instance size ] Klass
50 // [java mirror ] Klass
51 // [super ] Klass
52 // [access_flags ] Klass
53 // [name ] Klass
54 // [first subklass ] Klass
55 // [next sibling ] Klass
56 // [array klasses ]
57 // [methods ]
58 // [local interfaces ]
59 // [transitive interfaces ]
60 // [fields ]
61 // [constants ]
62 // [class loader ]
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 class MemberNameTable;
94
95 // This is used in iterators below.
96 class FieldClosure: public StackObj {
97 public:
98 virtual void do_field(fieldDescriptor* fd) = 0;
99 };
100
101 #ifndef PRODUCT
102 // Print fields.
103 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
104 class FieldPrinter: public FieldClosure {
105 oop _obj;
106 outputStream* _st;
107 public:
108 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
109 void do_field(fieldDescriptor* fd);
110 };
111 #endif // !PRODUCT
112
113 // ValueObjs embedded in klass. Describes where oops are located in instances of
114 // this klass.
115 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
116 public:
117 // Byte offset of the first oop mapped by this block.
118 int offset() const { return _offset; }
119 void set_offset(int offset) { _offset = offset; }
120
121 // Number of oops in this block.
122 uint count() const { return _count; }
123 void set_count(uint count) { _count = count; }
124
125 // sizeof(OopMapBlock) in HeapWords.
126 static const int size_in_words() {
127 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
128 LogHeapWordSize;
129 }
130
131 private:
132 int _offset;
133 uint _count;
134 };
135
136 struct JvmtiCachedClassFileData;
137
138 class InstanceKlass: public Klass {
139 friend class VMStructs;
140 friend class ClassFileParser;
141 friend class CompileReplay;
142
143 protected:
144 // Constructor
145 InstanceKlass(int vtable_len,
146 int itable_len,
147 int static_field_size,
148 int nonstatic_oop_map_size,
149 ReferenceType rt,
150 AccessFlags access_flags,
151 bool is_anonymous);
152 public:
153 static InstanceKlass* allocate_instance_klass(
154 ClassLoaderData* loader_data,
155 int vtable_len,
156 int itable_len,
157 int static_field_size,
158 int nonstatic_oop_map_size,
159 ReferenceType rt,
160 AccessFlags access_flags,
161 Symbol* name,
162 Klass* super_klass,
163 bool is_anonymous,
164 TRAPS);
165
166 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
167
168 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
169 // of the class loading & initialization procedure, and the use of the states.
170 enum ClassState {
171 allocated, // allocated (but not yet linked)
172 loaded, // loaded and inserted in class hierarchy (but not linked yet)
173 linked, // successfully linked/verified (but not initialized yet)
174 being_initialized, // currently running class initializer
175 fully_initialized, // initialized (successfull final state)
176 initialization_error // error happened during initialization
177 };
178
179 static int number_of_instance_classes() { return _total_instanceKlass_count; }
180
181 private:
182 static volatile int _total_instanceKlass_count;
183
184 protected:
185 // Annotations for this class
186 Annotations* _annotations;
187 // Array classes holding elements of this class.
188 Klass* _array_klasses;
189 // Constant pool for this class.
190 ConstantPool* _constants;
191 // The InnerClasses attribute and EnclosingMethod attribute. The
192 // _inner_classes is an array of shorts. If the class has InnerClasses
193 // attribute, then the _inner_classes array begins with 4-tuples of shorts
194 // [inner_class_info_index, outer_class_info_index,
195 // inner_name_index, inner_class_access_flags] for the InnerClasses
196 // attribute. If the EnclosingMethod attribute exists, it occupies the
197 // last two shorts [class_index, method_index] of the array. If only
198 // the InnerClasses attribute exists, the _inner_classes array length is
199 // number_of_inner_classes * 4. If the class has both InnerClasses
200 // and EnclosingMethod attributes the _inner_classes array length is
201 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
202 Array<jushort>* _inner_classes;
203
204 // the source debug extension for this klass, NULL if not specified.
205 // Specified as UTF-8 string without terminating zero byte in the classfile,
206 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
207 char* _source_debug_extension;
208 // Array name derived from this class which needs unreferencing
209 // if this class is unloaded.
210 Symbol* _array_name;
211
212 // Number of heapOopSize words used by non-static fields in this klass
213 // (including inherited fields but after header_size()).
214 int _nonstatic_field_size;
215 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
216 // Constant pool index to the utf8 entry of the Generic signature,
217 // or 0 if none.
218 u2 _generic_signature_index;
219 // Constant pool index to the utf8 entry for the name of source file
220 // containing this klass, 0 if not specified.
221 u2 _source_file_name_index;
222 u2 _static_oop_field_count;// number of static oop fields in this klass
223 u2 _java_fields_count; // The number of declared Java fields
224 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
225
226 // _is_marked_dependent can be set concurrently, thus cannot be part of the
227 // _misc_flags.
228 bool _is_marked_dependent; // used for marking during flushing and deoptimization
229
230 enum {
231 _misc_rewritten = 1 << 0, // methods rewritten.
232 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
233 _misc_should_verify_class = 1 << 2, // allow caching of preverification
234 _misc_is_anonymous = 1 << 3, // has embedded _host_klass field
235 _misc_is_contended = 1 << 4, // marked with contended annotation
236 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods
237 };
238 u2 _misc_flags;
239 u2 _minor_version; // minor version number of class file
240 u2 _major_version; // major version number of class file
241 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
242 int _vtable_len; // length of Java vtable (in words)
243 int _itable_len; // length of Java itable (in words)
244 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
245 MemberNameTable* _member_names; // Member names
246 JNIid* _jni_ids; // First JNI identifier for static fields in this class
247 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
248 nmethodBucket* _dependencies; // list of dependent nmethods
249 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
250 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
251 // Array of interesting part(s) of the previous version(s) of this
252 // InstanceKlass. See PreviousVersionWalker below.
253 GrowableArray<PreviousVersionNode *>* _previous_versions;
254 // JVMTI fields can be moved to their own structure - see 6315920
255 // JVMTI: cached class file, before retransformable agent modified it in CFLH
256 JvmtiCachedClassFileData* _cached_class_file;
257
258 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
259
260 // Class states are defined as ClassState (see above).
261 // Place the _init_state here to utilize the unused 2-byte after
262 // _idnum_allocated_count.
263 u1 _init_state; // state of class
264 u1 _reference_type; // reference type
265
266 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
267
268 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
269
270 // Method array.
271 Array<Method*>* _methods;
272 // Default Method Array, concrete methods inherited from interfaces
273 Array<Method*>* _default_methods;
274 // Interface (Klass*s) this class declares locally to implement.
275 Array<Klass*>* _local_interfaces;
276 // Interface (Klass*s) this class implements transitively.
277 Array<Klass*>* _transitive_interfaces;
278 // Int array containing the original order of method in the class file (for JVMTI).
279 Array<int>* _method_ordering;
280 // Int array containing the vtable_indices for default_methods
281 // offset matches _default_methods offset
282 Array<int>* _default_vtable_indices;
283
284 // Instance and static variable information, starts with 6-tuples of shorts
285 // [access, name index, sig index, initval index, low_offset, high_offset]
286 // for all fields, followed by the generic signature data at the end of
287 // the array. Only fields with generic signature attributes have the generic
288 // signature data set in the array. The fields array looks like following:
289 //
290 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
291 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
292 // ...
293 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
294 // [generic signature index]
295 // [generic signature index]
296 // ...
297 Array<u2>* _fields;
298
299 // embedded Java vtable follows here
300 // embedded Java itables follows here
301 // embedded static fields follows here
302 // embedded nonstatic oop-map blocks follows here
303 // embedded implementor of this interface follows here
304 // The embedded implementor only exists if the current klass is an
305 // iterface. The possible values of the implementor fall into following
306 // three cases:
307 // NULL: no implementor.
308 // A Klass* that's not itself: one implementor.
309 // Itsef: more than one implementors.
310 // embedded host klass follows here
311 // The embedded host klass only exists in an anonymous class for
312 // dynamic language support (JSR 292 enabled). The host class grants
313 // its access privileges to this class also. The host class is either
314 // named, or a previously loaded anonymous class. A non-anonymous class
315 // or an anonymous class loaded through normal classloading does not
316 // have this embedded field.
317 //
318
319 friend class SystemDictionary;
320
321 public:
322 bool has_nonstatic_fields() const {
323 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
324 }
325 void set_has_nonstatic_fields(bool b) {
326 if (b) {
327 _misc_flags |= _misc_has_nonstatic_fields;
328 } else {
329 _misc_flags &= ~_misc_has_nonstatic_fields;
330 }
331 }
332
333 // field sizes
334 int nonstatic_field_size() const { return _nonstatic_field_size; }
335 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
336
337 int static_field_size() const { return _static_field_size; }
338 void set_static_field_size(int size) { _static_field_size = size; }
339
340 int static_oop_field_count() const { return (int)_static_oop_field_count; }
341 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
342
343 // Java vtable
344 int vtable_length() const { return _vtable_len; }
345 void set_vtable_length(int len) { _vtable_len = len; }
346
347 // Java itable
348 int itable_length() const { return _itable_len; }
349 void set_itable_length(int len) { _itable_len = len; }
350
351 // array klasses
352 Klass* array_klasses() const { return _array_klasses; }
353 void set_array_klasses(Klass* k) { _array_klasses = k; }
354
355 // methods
356 Array<Method*>* methods() const { return _methods; }
357 void set_methods(Array<Method*>* a) { _methods = a; }
358 Method* method_with_idnum(int idnum);
359
360 // method ordering
361 Array<int>* method_ordering() const { return _method_ordering; }
362 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
363 void copy_method_ordering(intArray* m, TRAPS);
364
365 // default_methods
366 Array<Method*>* default_methods() const { return _default_methods; }
367 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
368
369 // default method vtable_indices
370 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
371 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
372 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
373
374 // interfaces
375 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
376 void set_local_interfaces(Array<Klass*>* a) {
377 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
378 _local_interfaces = a; }
379
380 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
381 void set_transitive_interfaces(Array<Klass*>* a) {
382 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
383 _transitive_interfaces = a;
384 }
385
386 private:
387 friend class fieldDescriptor;
388 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
389
390 public:
391 int field_offset (int index) const { return field(index)->offset(); }
392 int field_access_flags(int index) const { return field(index)->access_flags(); }
393 Symbol* field_name (int index) const { return field(index)->name(constants()); }
394 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
395
396 // Number of Java declared fields
397 int java_fields_count() const { return (int)_java_fields_count; }
398
399 Array<u2>* fields() const { return _fields; }
400 void set_fields(Array<u2>* f, u2 java_fields_count) {
401 guarantee(_fields == NULL || f == NULL, "Just checking");
402 _fields = f;
403 _java_fields_count = java_fields_count;
404 }
405
406 // inner classes
407 Array<u2>* inner_classes() const { return _inner_classes; }
408 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
409
410 enum InnerClassAttributeOffset {
411 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
412 inner_class_inner_class_info_offset = 0,
413 inner_class_outer_class_info_offset = 1,
414 inner_class_inner_name_offset = 2,
415 inner_class_access_flags_offset = 3,
416 inner_class_next_offset = 4
417 };
418
419 enum EnclosingMethodAttributeOffset {
420 enclosing_method_class_index_offset = 0,
421 enclosing_method_method_index_offset = 1,
422 enclosing_method_attribute_size = 2
423 };
424
425 // method override check
426 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
427
428 // package
429 bool is_same_class_package(Klass* class2);
430 bool is_same_class_package(oop classloader2, Symbol* classname2);
431 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
432
433 // find an enclosing class (defined where original code was, in jvm.cpp!)
434 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
435 instanceKlassHandle self(THREAD, this);
436 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
437 }
438 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
439 bool* inner_is_member, TRAPS);
440
441 // tell if two classes have the same enclosing class (at package level)
442 bool is_same_package_member(Klass* class2, TRAPS) {
443 instanceKlassHandle self(THREAD, this);
444 return is_same_package_member_impl(self, class2, THREAD);
445 }
446 static bool is_same_package_member_impl(instanceKlassHandle self,
447 Klass* class2, TRAPS);
448
449 // initialization state
450 bool is_loaded() const { return _init_state >= loaded; }
451 bool is_linked() const { return _init_state >= linked; }
452 bool is_initialized() const { return _init_state == fully_initialized; }
453 bool is_not_initialized() const { return _init_state < being_initialized; }
454 bool is_being_initialized() const { return _init_state == being_initialized; }
455 bool is_in_error_state() const { return _init_state == initialization_error; }
456 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
457 ClassState init_state() { return (ClassState)_init_state; }
458 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
459
460 // defineClass specified verification
461 bool should_verify_class() const {
462 return (_misc_flags & _misc_should_verify_class) != 0;
463 }
464 void set_should_verify_class(bool value) {
465 if (value) {
466 _misc_flags |= _misc_should_verify_class;
467 } else {
468 _misc_flags &= ~_misc_should_verify_class;
469 }
470 }
471
472 // marking
473 bool is_marked_dependent() const { return _is_marked_dependent; }
474 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
475
476 // initialization (virtuals from Klass)
477 bool should_be_initialized() const; // means that initialize should be called
478 void initialize(TRAPS);
479 void link_class(TRAPS);
480 bool link_class_or_fail(TRAPS); // returns false on failure
481 void unlink_class();
482 void rewrite_class(TRAPS);
483 void link_methods(TRAPS);
484 Method* class_initializer();
485
486 // set the class to initialized if no static initializer is present
487 void eager_initialize(Thread *thread);
488
489 // reference type
490 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
491 void set_reference_type(ReferenceType t) {
492 assert(t == (u1)t, "overflow");
493 _reference_type = (u1)t;
494 }
495
496 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
497
498 // find local field, returns true if found
499 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
500 // find field in direct superinterfaces, returns the interface in which the field is defined
501 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
502 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
503 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
504 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
505 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
506
507 // find a non-static or static field given its offset within the class.
508 bool contains_field_offset(int offset) {
509 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
510 }
511
512 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
513 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
514
515 // find a local method (returns NULL if not found)
516 Method* find_method(Symbol* name, Symbol* signature) const;
517 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
518 static Method* find_instance_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
519
520 // find a local method index in default_methods (returns -1 if not found)
521 static int find_method_index(Array<Method*>* methods, Symbol* name, Symbol* signature);
522
523 // lookup operation (returns NULL if not found)
524 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const;
525
526 // lookup a method in all the interfaces that this class implements
527 // (returns NULL if not found)
528 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, bool skip_default_methods) const;
529
530 // lookup a method in local defaults then in all interfaces
531 // (returns NULL if not found)
532 Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
533
534 // Find method indices by name. If a method with the specified name is
535 // found the index to the first method is returned, and 'end' is filled in
536 // with the index of first non-name-matching method. If no method is found
537 // -1 is returned.
538 int find_method_by_name(Symbol* name, int* end);
539 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
540
541 // constant pool
542 ConstantPool* constants() const { return _constants; }
543 void set_constants(ConstantPool* c) { _constants = c; }
544
545 // protection domain
546 oop protection_domain() const;
547
548 // signers
549 objArrayOop signers() const;
550
551 // host class
552 Klass* host_klass() const {
553 Klass** hk = (Klass**)adr_host_klass();
554 if (hk == NULL) {
555 return NULL;
556 } else {
557 return *hk;
558 }
559 }
560 void set_host_klass(Klass* host) {
561 assert(is_anonymous(), "not anonymous");
562 Klass** addr = (Klass**)adr_host_klass();
563 assert(addr != NULL, "no reversed space");
564 if (addr != NULL) {
565 *addr = host;
566 }
567 }
568 bool is_anonymous() const {
569 return (_misc_flags & _misc_is_anonymous) != 0;
570 }
571 void set_is_anonymous(bool value) {
572 if (value) {
573 _misc_flags |= _misc_is_anonymous;
574 } else {
575 _misc_flags &= ~_misc_is_anonymous;
576 }
577 }
578
579 // Oop that keeps the metadata for this class from being unloaded
580 // in places where the metadata is stored in other places, like nmethods
581 oop klass_holder() const {
582 return is_anonymous() ? java_mirror() : class_loader();
583 }
584
585 bool is_contended() const {
586 return (_misc_flags & _misc_is_contended) != 0;
587 }
588 void set_is_contended(bool value) {
589 if (value) {
590 _misc_flags |= _misc_is_contended;
591 } else {
592 _misc_flags &= ~_misc_is_contended;
593 }
594 }
595
596 // source file name
597 Symbol* source_file_name() const {
598 return (_source_file_name_index == 0) ?
599 (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
600 }
601 u2 source_file_name_index() const {
602 return _source_file_name_index;
603 }
604 void set_source_file_name_index(u2 sourcefile_index) {
605 _source_file_name_index = sourcefile_index;
606 }
607
608 // minor and major version numbers of class file
609 u2 minor_version() const { return _minor_version; }
610 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
611 u2 major_version() const { return _major_version; }
612 void set_major_version(u2 major_version) { _major_version = major_version; }
613
614 // source debug extension
615 char* source_debug_extension() const { return _source_debug_extension; }
616 void set_source_debug_extension(char* array, int length);
617
618 // symbol unloading support (refcount already added)
619 Symbol* array_name() { return _array_name; }
620 void set_array_name(Symbol* name) { assert(_array_name == NULL || name == NULL, "name already created"); _array_name = name; }
621
622 // nonstatic oop-map blocks
623 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
624 return oop_map_count * OopMapBlock::size_in_words();
625 }
626 unsigned int nonstatic_oop_map_count() const {
627 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
628 }
629 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
630 void set_nonstatic_oop_map_size(int words) {
631 _nonstatic_oop_map_size = words;
632 }
633
634 // RedefineClasses() support for previous versions:
635 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
636 int emcp_method_count);
637 // If the _previous_versions array is non-NULL, then this klass
638 // has been redefined at least once even if we aren't currently
639 // tracking a previous version.
640 bool has_been_redefined() const { return _previous_versions != NULL; }
641 bool has_previous_version() const;
642 void init_previous_versions() {
643 _previous_versions = NULL;
644 }
645 GrowableArray<PreviousVersionNode *>* previous_versions() const {
646 return _previous_versions;
647 }
648
649 static void purge_previous_versions(InstanceKlass* ik);
650
651 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
652 void set_cached_class_file(JvmtiCachedClassFileData *data) {
653 _cached_class_file = data;
654 }
655 JvmtiCachedClassFileData * get_cached_class_file() { return _cached_class_file; }
656 jint get_cached_class_file_len();
657 unsigned char * get_cached_class_file_bytes();
658
659 // JVMTI: Support for caching of field indices, types, and offsets
660 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
661 _jvmti_cached_class_field_map = descriptor;
662 }
663 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
664 return _jvmti_cached_class_field_map;
665 }
666
667 bool has_default_methods() const {
668 return (_misc_flags & _misc_has_default_methods) != 0;
669 }
670 void set_has_default_methods(bool b) {
671 if (b) {
672 _misc_flags |= _misc_has_default_methods;
673 } else {
674 _misc_flags &= ~_misc_has_default_methods;
675 }
676 }
677
678 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
679 inline u2 next_method_idnum();
680 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
681
682 // generics support
683 Symbol* generic_signature() const {
684 return (_generic_signature_index == 0) ?
685 (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
686 }
687 u2 generic_signature_index() const {
688 return _generic_signature_index;
689 }
690 void set_generic_signature_index(u2 sig_index) {
691 _generic_signature_index = sig_index;
692 }
693
694 u2 enclosing_method_data(int offset);
695 u2 enclosing_method_class_index() {
696 return enclosing_method_data(enclosing_method_class_index_offset);
697 }
698 u2 enclosing_method_method_index() {
699 return enclosing_method_data(enclosing_method_method_index_offset);
700 }
701 void set_enclosing_method_indices(u2 class_index,
702 u2 method_index);
703
704 // jmethodID support
705 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
706 methodHandle method_h);
707 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
708 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
709 jmethodID* to_dealloc_id_p,
710 jmethodID** to_dealloc_jmeths_p);
711 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
712 size_t *length_p, jmethodID* id_p);
713 jmethodID jmethod_id_or_null(Method* method);
714
715 // annotations support
716 Annotations* annotations() const { return _annotations; }
717 void set_annotations(Annotations* anno) { _annotations = anno; }
718
719 AnnotationArray* class_annotations() const {
720 return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
721 }
722 Array<AnnotationArray*>* fields_annotations() const {
723 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
724 }
725 AnnotationArray* class_type_annotations() const {
726 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
727 }
728 Array<AnnotationArray*>* fields_type_annotations() const {
729 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
730 }
731 // allocation
732 instanceOop allocate_instance(TRAPS);
733
734 // additional member function to return a handle
735 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
736
737 objArrayOop allocate_objArray(int n, int length, TRAPS);
738 // Helper function
739 static instanceOop register_finalizer(instanceOop i, TRAPS);
740
741 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
742 // if not, throw either an Error or an Exception.
743 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
744
745 // initialization
746 void call_class_initializer(TRAPS);
747 void set_initialization_state_and_notify(ClassState state, TRAPS);
748
749 // OopMapCache support
750 OopMapCache* oop_map_cache() { return _oop_map_cache; }
751 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
752 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
753
754 // JNI identifier support (for static fields - for jni performance)
755 JNIid* jni_ids() { return _jni_ids; }
756 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
757 JNIid* jni_id_for(int offset);
758
759 // maintenance of deoptimization dependencies
760 int mark_dependent_nmethods(DepChange& changes);
761 void add_dependent_nmethod(nmethod* nm);
762 void remove_dependent_nmethod(nmethod* nm);
763
764 // On-stack replacement support
765 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
766 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
767 void add_osr_nmethod(nmethod* n);
768 void remove_osr_nmethod(nmethod* n);
769 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
770
771 // Breakpoint support (see methods on Method* for details)
772 BreakpointInfo* breakpoints() const { return _breakpoints; };
773 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
774
775 // support for stub routines
776 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
777 TRACE_DEFINE_OFFSET;
778 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
779
780 // subclass/subinterface checks
781 bool implements_interface(Klass* k) const;
782 bool is_same_or_direct_interface(Klass* k) const;
783
784 // Access to the implementor of an interface.
785 Klass* implementor() const
786 {
787 Klass** k = adr_implementor();
788 if (k == NULL) {
789 return NULL;
790 } else {
791 return *k;
792 }
793 }
794
795 void set_implementor(Klass* k) {
796 assert(is_interface(), "not interface");
797 Klass** addr = adr_implementor();
798 assert(addr != NULL, "null addr");
799 if (addr != NULL) {
800 *addr = k;
801 }
802 }
803
804 int nof_implementors() const {
805 Klass* k = implementor();
806 if (k == NULL) {
807 return 0;
808 } else if (k != this) {
809 return 1;
810 } else {
811 return 2;
812 }
813 }
814
815 void add_implementor(Klass* k); // k is a new class that implements this interface
816 void init_implementor(); // initialize
817
818 // link this class into the implementors list of every interface it implements
819 void process_interfaces(Thread *thread);
820
821 // virtual operations from Klass
822 bool is_leaf_class() const { return _subklass == NULL; }
823 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
824 bool compute_is_subtype_of(Klass* k);
825 bool can_be_primary_super_slow() const;
826 int oop_size(oop obj) const { return size_helper(); }
827 bool oop_is_instance_slow() const { return true; }
828
829 // Iterators
830 void do_local_static_fields(FieldClosure* cl);
831 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
832 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
833
834 void methods_do(void f(Method* method));
835 void array_klasses_do(void f(Klass* k));
836 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
837 bool super_types_do(SuperTypeClosure* blk);
838
839 // Casting from Klass*
840 static InstanceKlass* cast(Klass* k) {
841 assert(k->is_klass(), "must be");
842 assert(k->oop_is_instance(), "cast to InstanceKlass");
843 return (InstanceKlass*) k;
844 }
845
846 InstanceKlass* java_super() const {
847 return (super() == NULL) ? NULL : cast(super());
848 }
849
850 // Sizing (in words)
851 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
852
853 static int size(int vtable_length, int itable_length,
854 int nonstatic_oop_map_size,
855 bool is_interface, bool is_anonymous) {
856 return align_object_size(header_size() +
857 align_object_offset(vtable_length) +
858 align_object_offset(itable_length) +
859 ((is_interface || is_anonymous) ?
860 align_object_offset(nonstatic_oop_map_size) :
861 nonstatic_oop_map_size) +
862 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
863 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
864 }
865 int size() const { return size(vtable_length(),
866 itable_length(),
867 nonstatic_oop_map_size(),
868 is_interface(),
869 is_anonymous());
870 }
871 #if INCLUDE_SERVICES
872 virtual void collect_statistics(KlassSizeStats *sz) const;
873 #endif
874
875 static int vtable_start_offset() { return header_size(); }
876 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
877
878 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
879 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
880 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
881
882 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
883
884 address static_field_addr(int offset);
885
886 OopMapBlock* start_of_nonstatic_oop_maps() const {
887 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
888 }
889
890 Klass** end_of_nonstatic_oop_maps() const {
891 return (Klass**)(start_of_nonstatic_oop_maps() +
892 nonstatic_oop_map_count());
893 }
894
895 Klass** adr_implementor() const {
896 if (is_interface()) {
897 return (Klass**)end_of_nonstatic_oop_maps();
898 } else {
899 return NULL;
900 }
901 };
902
903 Klass** adr_host_klass() const {
904 if (is_anonymous()) {
905 Klass** adr_impl = adr_implementor();
906 if (adr_impl != NULL) {
907 return adr_impl + 1;
908 } else {
909 return end_of_nonstatic_oop_maps();
910 }
911 } else {
912 return NULL;
913 }
914 }
915
916 // Use this to return the size of an instance in heap words:
917 int size_helper() const {
918 return layout_helper_to_size_helper(layout_helper());
919 }
920
921 // This bit is initialized in classFileParser.cpp.
922 // It is false under any of the following conditions:
923 // - the class is abstract (including any interface)
924 // - the class has a finalizer (if !RegisterFinalizersAtInit)
925 // - the class size is larger than FastAllocateSizeLimit
926 // - the class is java/lang/Class, which cannot be allocated directly
927 bool can_be_fastpath_allocated() const {
928 return !layout_helper_needs_slow_path(layout_helper());
929 }
930
931 // Java vtable/itable
932 klassVtable* vtable() const; // return new klassVtable wrapper
933 inline Method* method_at_vtable(int index);
934 klassItable* itable() const; // return new klassItable wrapper
935 Method* method_at_itable(Klass* holder, int index, TRAPS);
936
937 #if INCLUDE_JVMTI
938 void adjust_default_methods(Method** old_methods, Method** new_methods,
939 int methods_length, bool* trace_name_printed);
940 #endif // INCLUDE_JVMTI
941
942 // Garbage collection
943 void oop_follow_contents(oop obj);
944 int oop_adjust_pointers(oop obj);
945
946 void clean_implementors_list(BoolObjectClosure* is_alive);
947 void clean_method_data(BoolObjectClosure* is_alive);
948
949 // Explicit metaspace deallocation of fields
950 // For RedefineClasses and class file parsing errors, we need to deallocate
951 // instanceKlasses and the metadata they point to.
952 void deallocate_contents(ClassLoaderData* loader_data);
953 static void deallocate_methods(ClassLoaderData* loader_data,
954 Array<Method*>* methods);
955 void static deallocate_interfaces(ClassLoaderData* loader_data,
956 Klass* super_klass,
957 Array<Klass*>* local_interfaces,
958 Array<Klass*>* transitive_interfaces);
959
960 // The constant pool is on stack if any of the methods are executing or
961 // referenced by handles.
962 bool on_stack() const { return _constants->on_stack(); }
963
964 // callbacks for actions during class unloading
965 static void notify_unload_class(InstanceKlass* ik);
966 static void release_C_heap_structures(InstanceKlass* ik);
967
968 // Parallel Scavenge and Parallel Old
969 PARALLEL_GC_DECLS
970
971 // Naming
972 const char* signature_name() const;
973
974 // Iterators
975 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
976 return oop_oop_iterate_v(obj, blk);
977 }
978
979 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
980 return oop_oop_iterate_v_m(obj, blk, mr);
981 }
982
983 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
984 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
985 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
986 MemRegion mr);
987
988 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
989 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
990
991 #if INCLUDE_ALL_GCS
992 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
993 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
994
995 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
996 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
997 #endif // INCLUDE_ALL_GCS
998
999 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
1000
1001 private:
1002 // initialization state
1003 #ifdef ASSERT
1004 void set_init_state(ClassState state);
1005 #else
1006 void set_init_state(ClassState state) { _init_state = (u1)state; }
1007 #endif
1008 void set_rewritten() { _misc_flags |= _misc_rewritten; }
1009 void set_init_thread(Thread *thread) { _init_thread = thread; }
1010
1011 // The RedefineClasses() API can cause new method idnums to be needed
1012 // which will cause the caches to grow. Safety requires different
1013 // cache management logic if the caches can grow instead of just
1014 // going from NULL to non-NULL.
1015 bool idnum_can_increment() const { return has_been_redefined(); }
1016 jmethodID* methods_jmethod_ids_acquire() const
1017 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
1018 void release_set_methods_jmethod_ids(jmethodID* jmeths)
1019 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
1020
1021 // Lock during initialization
1022 public:
1023 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1024 // Must be one per class and it has to be a VM internal object so java code
1025 // cannot lock it (like the mirror).
1026 // It has to be an object not a Mutex because it's held through java calls.
1027 oop init_lock() const;
1028 private:
1029 void fence_and_clear_init_lock();
1030
1031 // Static methods that are used to implement member methods where an exposed this pointer
1032 // is needed due to possible GCs
1033 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1034 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1035 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
1036 static void eager_initialize_impl (instanceKlassHandle this_oop);
1037 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
1038 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
1039 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
1040 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
1041 /* jni_id_for_impl for jfieldID only */
1042 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
1043
1044 // Returns the array class for the n'th dimension
1045 Klass* array_klass_impl(bool or_null, int n, TRAPS);
1046
1047 // Returns the array class with this class as element type
1048 Klass* array_klass_impl(bool or_null, TRAPS);
1049
1050 // Free CHeap allocated fields.
1051 void release_C_heap_structures();
1052 public:
1053 // CDS support - remove and restore oops from metadata. Oops are not shared.
1054 virtual void remove_unshareable_info();
1055 virtual void restore_unshareable_info(TRAPS);
1056
1057 // jvm support
1058 jint compute_modifier_flags(TRAPS) const;
1059
1060 // JSR-292 support
1061 MemberNameTable* member_names() { return _member_names; }
1062 void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1063 void add_member_name(int index, Handle member_name);
1064 oop get_member_name(int index);
1065
1066 public:
1067 // JVMTI support
1068 jint jvmti_class_status() const;
1069
1070 public:
1071 // Printing
1072 #ifndef PRODUCT
1073 void print_on(outputStream* st) const;
1074 #endif
1075 void print_value_on(outputStream* st) const;
1076
1077 void oop_print_value_on(oop obj, outputStream* st);
1078
1079 #ifndef PRODUCT
1080 void oop_print_on (oop obj, outputStream* st);
1081
1082 void print_dependent_nmethods(bool verbose = false);
1083 bool is_dependent_nmethod(nmethod* nm);
1084 #endif
1085
1086 const char* internal_name() const;
1087
1088 // Verification
1089 void verify_on(outputStream* st, bool check_dictionary);
1090
1091 void oop_verify_on(oop obj, outputStream* st);
1092 };
1093
1094 inline Method* InstanceKlass::method_at_vtable(int index) {
1095 #ifndef PRODUCT
1096 assert(index >= 0, "valid vtable index");
1097 if (DebugVtables) {
1098 verify_vtable_index(index);
1099 }
1100 #endif
1101 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1102 return ve[index].method();
1103 }
1104
1105 // for adding methods
1106 // UNSET_IDNUM return means no more ids available
1107 inline u2 InstanceKlass::next_method_idnum() {
1108 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1109 return ConstMethod::UNSET_IDNUM; // no more ids available
1110 } else {
1111 return _idnum_allocated_count++;
1112 }
1113 }
1114
1115
1116 /* JNIid class for jfieldIDs only */
1117 class JNIid: public CHeapObj<mtClass> {
1118 friend class VMStructs;
1119 private:
1120 Klass* _holder;
1121 JNIid* _next;
1122 int _offset;
1123 #ifdef ASSERT
1124 bool _is_static_field_id;
1125 #endif
1126
1127 public:
1128 // Accessors
1129 Klass* holder() const { return _holder; }
1130 int offset() const { return _offset; }
1131 JNIid* next() { return _next; }
1132 // Constructor
1133 JNIid(Klass* holder, int offset, JNIid* next);
1134 // Identifier lookup
1135 JNIid* find(int offset);
1136
1137 bool find_local_field(fieldDescriptor* fd) {
1138 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1139 }
1140
1141 static void deallocate(JNIid* id);
1142 // Debugging
1143 #ifdef ASSERT
1144 bool is_static_field_id() const { return _is_static_field_id; }
1145 void set_is_static_field_id() { _is_static_field_id = true; }
1146 #endif
1147 void verify(Klass* holder);
1148 };
1149
1150
1151 // If breakpoints are more numerous than just JVMTI breakpoints,
1152 // consider compressing this data structure.
1153 // It is currently a simple linked list defined in method.hpp.
1154
1155 class BreakpointInfo;
1156
1157
1158 // A collection point for interesting information about the previous
1159 // version(s) of an InstanceKlass. A GrowableArray of PreviousVersionNodes
1160 // is attached to the InstanceKlass as needed. See PreviousVersionWalker below.
1161 class PreviousVersionNode : public CHeapObj<mtClass> {
1162 private:
1163 ConstantPool* _prev_constant_pool;
1164
1165 // If the previous version of the InstanceKlass doesn't have any
1166 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1167 // EMCP methods have been collected, then _prev_EMCP_methods can
1168 // have a length of zero.
1169 GrowableArray<Method*>* _prev_EMCP_methods;
1170
1171 public:
1172 PreviousVersionNode(ConstantPool* prev_constant_pool,
1173 GrowableArray<Method*>* prev_EMCP_methods);
1174 ~PreviousVersionNode();
1175 ConstantPool* prev_constant_pool() const {
1176 return _prev_constant_pool;
1177 }
1178 GrowableArray<Method*>* prev_EMCP_methods() const {
1179 return _prev_EMCP_methods;
1180 }
1181 };
1182
1183
1184 // Helper object for walking previous versions.
1185 class PreviousVersionWalker : public StackObj {
1186 private:
1187 Thread* _thread;
1188 GrowableArray<PreviousVersionNode *>* _previous_versions;
1189 int _current_index;
1190
1191 // A pointer to the current node object so we can handle the deletes.
1192 PreviousVersionNode* _current_p;
1193
1194 // The constant pool handle keeps all the methods in this class from being
1195 // deallocated from the metaspace during class unloading.
1196 constantPoolHandle _current_constant_pool_handle;
1197
1198 public:
1199 PreviousVersionWalker(Thread* thread, InstanceKlass *ik);
1200
1201 // Return the interesting information for the next previous version
1202 // of the klass. Returns NULL if there are no more previous versions.
1203 PreviousVersionNode* next_previous_version();
1204 };
1205
1206
1207 //
1208 // nmethodBucket is used to record dependent nmethods for
1209 // deoptimization. nmethod dependencies are actually <klass, method>
1210 // pairs but we really only care about the klass part for purposes of
1211 // finding nmethods which might need to be deoptimized. Instead of
1212 // recording the method, a count of how many times a particular nmethod
1213 // was recorded is kept. This ensures that any recording errors are
1214 // noticed since an nmethod should be removed as many times are it's
1215 // added.
1216 //
1217 class nmethodBucket: public CHeapObj<mtClass> {
1218 friend class VMStructs;
1219 private:
1220 nmethod* _nmethod;
1221 int _count;
1222 nmethodBucket* _next;
1223
1224 public:
1225 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1226 _nmethod = nmethod;
1227 _next = next;
1228 _count = 1;
1229 }
1230 int count() { return _count; }
1231 int increment() { _count += 1; return _count; }
1232 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1233 nmethodBucket* next() { return _next; }
1234 void set_next(nmethodBucket* b) { _next = b; }
1235 nmethod* get_nmethod() { return _nmethod; }
1236 };
1237
1238 // An iterator that's used to access the inner classes indices in the
1239 // InstanceKlass::_inner_classes array.
1240 class InnerClassesIterator : public StackObj {
1241 private:
1242 Array<jushort>* _inner_classes;
1243 int _length;
1244 int _idx;
1245 public:
1246
1247 InnerClassesIterator(instanceKlassHandle k) {
1248 _inner_classes = k->inner_classes();
1249 if (k->inner_classes() != NULL) {
1250 _length = _inner_classes->length();
1251 // The inner class array's length should be the multiple of
1252 // inner_class_next_offset if it only contains the InnerClasses
1253 // attribute data, or it should be
1254 // n*inner_class_next_offset+enclosing_method_attribute_size
1255 // if it also contains the EnclosingMethod data.
1256 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1257 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1258 "just checking");
1259 // Remove the enclosing_method portion if exists.
1260 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1261 _length -= InstanceKlass::enclosing_method_attribute_size;
1262 }
1263 } else {
1264 _length = 0;
1265 }
1266 _idx = 0;
1267 }
1268
1269 int length() const {
1270 return _length;
1271 }
1272
1273 void next() {
1274 _idx += InstanceKlass::inner_class_next_offset;
1275 }
1276
1277 bool done() const {
1278 return (_idx >= _length);
1279 }
1280
1281 u2 inner_class_info_index() const {
1282 return _inner_classes->at(
1283 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1284 }
1285
1286 void set_inner_class_info_index(u2 index) {
1287 _inner_classes->at_put(
1288 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1289 }
1290
1291 u2 outer_class_info_index() const {
1292 return _inner_classes->at(
1293 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1294 }
1295
1296 void set_outer_class_info_index(u2 index) {
1297 _inner_classes->at_put(
1298 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1299 }
1300
1301 u2 inner_name_index() const {
1302 return _inner_classes->at(
1303 _idx + InstanceKlass::inner_class_inner_name_offset);
1304 }
1305
1306 void set_inner_name_index(u2 index) {
1307 _inner_classes->at_put(
1308 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1309 }
1310
1311 u2 inner_access_flags() const {
1312 return _inner_classes->at(
1313 _idx + InstanceKlass::inner_class_access_flags_offset);
1314 }
1315 };
1316
1317 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP