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