1 /*
2 * Copyright (c) 1997, 2014, 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/handles.hpp"
36 #include "runtime/os.hpp"
37 #include "utilities/accessFlags.hpp"
38 #include "utilities/bitMap.inline.hpp"
39 #include "utilities/macros.hpp"
40 #include "trace/traceMacros.hpp"
41
42 // An InstanceKlass is the VM level representation of a Java class.
43 // It contains all information needed for at class at execution runtime.
44
45 // InstanceKlass embedded field layout (after declared fields):
46 // [EMBEDDED Java vtable ] size in words = vtable_len
47 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
48 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
49 // indicating where oops are located in instances of this klass.
50 // [EMBEDDED implementor of the interface] only exist for interface
51 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled)
52
53
54 // forward declaration for class -- see below for definition
55 class SuperTypeClosure;
56 class JNIid;
57 class jniIdMapBase;
58 class BreakpointInfo;
59 class fieldDescriptor;
60 class DepChange;
61 class nmethodBucket;
62 class PreviousVersionNode;
63 class JvmtiCachedClassFieldMap;
64 class MemberNameTable;
65
66 // This is used in iterators below.
67 class FieldClosure: public StackObj {
68 public:
69 virtual void do_field(fieldDescriptor* fd) = 0;
70 };
71
72 #ifndef PRODUCT
73 // Print fields.
74 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
75 class FieldPrinter: public FieldClosure {
76 oop _obj;
77 outputStream* _st;
78 public:
79 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
80 void do_field(fieldDescriptor* fd);
81 };
82 #endif // !PRODUCT
83
84 // ValueObjs embedded in klass. Describes where oops are located in instances of
85 // this klass.
86 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
87 public:
88 // Byte offset of the first oop mapped by this block.
89 int offset() const { return _offset; }
90 void set_offset(int offset) { _offset = offset; }
91
92 // Number of oops in this block.
93 uint count() const { return _count; }
94 void set_count(uint count) { _count = count; }
95
96 // sizeof(OopMapBlock) in HeapWords.
97 static const int size_in_words() {
98 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
99 LogHeapWordSize;
100 }
101
102 private:
103 int _offset;
104 uint _count;
105 };
106
107 struct JvmtiCachedClassFileData;
108
109 class InstanceKlass: public Klass {
110 friend class VMStructs;
111 friend class ClassFileParser;
112 friend class CompileReplay;
113
114 protected:
115 // Constructor
116 InstanceKlass(int vtable_len,
117 int itable_len,
118 int static_field_size,
119 int nonstatic_oop_map_size,
120 ReferenceType rt,
121 AccessFlags access_flags,
122 bool is_anonymous);
123 public:
124 static InstanceKlass* allocate_instance_klass(
125 ClassLoaderData* loader_data,
126 int vtable_len,
127 int itable_len,
128 int static_field_size,
129 int nonstatic_oop_map_size,
130 ReferenceType rt,
131 AccessFlags access_flags,
132 Symbol* name,
133 Klass* super_klass,
134 bool is_anonymous,
135 TRAPS);
136
137 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
138
139 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
140 // of the class loading & initialization procedure, and the use of the states.
141 enum ClassState {
142 allocated, // allocated (but not yet linked)
143 loaded, // loaded and inserted in class hierarchy (but not linked yet)
144 linked, // successfully linked/verified (but not initialized yet)
145 being_initialized, // currently running class initializer
146 fully_initialized, // initialized (successfull final state)
147 initialization_error // error happened during initialization
148 };
149
150 static int number_of_instance_classes() { return _total_instanceKlass_count; }
151
152 private:
153 static volatile int _total_instanceKlass_count;
154
155 protected:
156 // Annotations for this class
157 Annotations* _annotations;
158 // Array classes holding elements of this class.
159 Klass* _array_klasses;
160 // Constant pool for this class.
161 ConstantPool* _constants;
162 // The InnerClasses attribute and EnclosingMethod attribute. The
163 // _inner_classes is an array of shorts. If the class has InnerClasses
164 // attribute, then the _inner_classes array begins with 4-tuples of shorts
165 // [inner_class_info_index, outer_class_info_index,
166 // inner_name_index, inner_class_access_flags] for the InnerClasses
167 // attribute. If the EnclosingMethod attribute exists, it occupies the
168 // last two shorts [class_index, method_index] of the array. If only
169 // the InnerClasses attribute exists, the _inner_classes array length is
170 // number_of_inner_classes * 4. If the class has both InnerClasses
171 // and EnclosingMethod attributes the _inner_classes array length is
172 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
173 Array<jushort>* _inner_classes;
174
175 // the source debug extension for this klass, NULL if not specified.
176 // Specified as UTF-8 string without terminating zero byte in the classfile,
177 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
178 char* _source_debug_extension;
179 // Array name derived from this class which needs unreferencing
180 // if this class is unloaded.
181 Symbol* _array_name;
182
183 // Number of heapOopSize words used by non-static fields in this klass
184 // (including inherited fields but after header_size()).
185 int _nonstatic_field_size;
186 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
187 // Constant pool index to the utf8 entry of the Generic signature,
188 // or 0 if none.
189 u2 _generic_signature_index;
190 // Constant pool index to the utf8 entry for the name of source file
191 // containing this klass, 0 if not specified.
192 u2 _source_file_name_index;
193 u2 _static_oop_field_count;// number of static oop fields in this klass
194 u2 _java_fields_count; // The number of declared Java fields
195 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
196
197 // _is_marked_dependent can be set concurrently, thus cannot be part of the
198 // _misc_flags.
199 bool _is_marked_dependent; // used for marking during flushing and deoptimization
200 bool _has_unloaded_dependent;
201
202 enum {
203 _misc_rewritten = 1 << 0, // methods rewritten.
204 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
205 _misc_should_verify_class = 1 << 2, // allow caching of preverification
206 _misc_is_anonymous = 1 << 3, // has embedded _host_klass field
207 _misc_is_contended = 1 << 4, // marked with contended annotation
208 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods
209 };
210 u2 _misc_flags;
211 u2 _minor_version; // minor version number of class file
212 u2 _major_version; // major version number of class file
213 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
214 int _vtable_len; // length of Java vtable (in words)
215 int _itable_len; // length of Java itable (in words)
216 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
217 MemberNameTable* _member_names; // Member names
218 JNIid* _jni_ids; // First JNI identifier for static fields in this class
219 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
220 nmethodBucket* _dependencies; // list of dependent nmethods
221 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
222 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
223 // Array of interesting part(s) of the previous version(s) of this
224 // InstanceKlass. See PreviousVersionWalker below.
225 GrowableArray<PreviousVersionNode *>* _previous_versions;
226 // JVMTI fields can be moved to their own structure - see 6315920
227 // JVMTI: cached class file, before retransformable agent modified it in CFLH
228 JvmtiCachedClassFileData* _cached_class_file;
229
230 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
231
232 // Class states are defined as ClassState (see above).
233 // Place the _init_state here to utilize the unused 2-byte after
234 // _idnum_allocated_count.
235 u1 _init_state; // state of class
236 u1 _reference_type; // reference type
237
238 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
239
240 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
241
242 // Method array.
243 Array<Method*>* _methods;
244 // Default Method Array, concrete methods inherited from interfaces
245 Array<Method*>* _default_methods;
246 // Interface (Klass*s) this class declares locally to implement.
247 Array<Klass*>* _local_interfaces;
248 // Interface (Klass*s) this class implements transitively.
249 Array<Klass*>* _transitive_interfaces;
250 // Int array containing the original order of method in the class file (for JVMTI).
251 Array<int>* _method_ordering;
252 // Int array containing the vtable_indices for default_methods
253 // offset matches _default_methods offset
254 Array<int>* _default_vtable_indices;
255
256 // Instance and static variable information, starts with 6-tuples of shorts
257 // [access, name index, sig index, initval index, low_offset, high_offset]
258 // for all fields, followed by the generic signature data at the end of
259 // the array. Only fields with generic signature attributes have the generic
260 // signature data set in the array. The fields array looks like following:
261 //
262 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
263 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
264 // ...
265 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
266 // [generic signature index]
267 // [generic signature index]
268 // ...
269 Array<u2>* _fields;
270
271 // embedded Java vtable follows here
272 // embedded Java itables follows here
273 // embedded static fields follows here
274 // embedded nonstatic oop-map blocks follows here
275 // embedded implementor of this interface follows here
276 // The embedded implementor only exists if the current klass is an
277 // iterface. The possible values of the implementor fall into following
278 // three cases:
279 // NULL: no implementor.
280 // A Klass* that's not itself: one implementor.
281 // Itself: more than one implementors.
282 // embedded host klass follows here
283 // The embedded host klass only exists in an anonymous class for
284 // dynamic language support (JSR 292 enabled). The host class grants
285 // its access privileges to this class also. The host class is either
286 // named, or a previously loaded anonymous class. A non-anonymous class
287 // or an anonymous class loaded through normal classloading does not
288 // have this embedded field.
289 //
290
291 friend class SystemDictionary;
292
293 public:
294 bool has_nonstatic_fields() const {
295 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
296 }
297 void set_has_nonstatic_fields(bool b) {
298 if (b) {
299 _misc_flags |= _misc_has_nonstatic_fields;
300 } else {
301 _misc_flags &= ~_misc_has_nonstatic_fields;
302 }
303 }
304
305 // field sizes
306 int nonstatic_field_size() const { return _nonstatic_field_size; }
307 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
308
309 int static_field_size() const { return _static_field_size; }
310 void set_static_field_size(int size) { _static_field_size = size; }
311
312 int static_oop_field_count() const { return (int)_static_oop_field_count; }
313 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
314
315 // Java vtable
316 int vtable_length() const { return _vtable_len; }
317 void set_vtable_length(int len) { _vtable_len = len; }
318
319 // Java itable
320 int itable_length() const { return _itable_len; }
321 void set_itable_length(int len) { _itable_len = len; }
322
323 // array klasses
324 Klass* array_klasses() const { return _array_klasses; }
325 void set_array_klasses(Klass* k) { _array_klasses = k; }
326
327 // methods
328 Array<Method*>* methods() const { return _methods; }
329 void set_methods(Array<Method*>* a) { _methods = a; }
330 Method* method_with_idnum(int idnum);
331
332 // method ordering
333 Array<int>* method_ordering() const { return _method_ordering; }
334 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
335 void copy_method_ordering(intArray* m, TRAPS);
336
337 // default_methods
338 Array<Method*>* default_methods() const { return _default_methods; }
339 void set_default_methods(Array<Method*>* a) { _default_methods = a; }
340
341 // default method vtable_indices
342 Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
343 void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
344 Array<int>* create_new_default_vtable_indices(int len, TRAPS);
345
346 // interfaces
347 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
348 void set_local_interfaces(Array<Klass*>* a) {
349 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
350 _local_interfaces = a; }
351
352 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
353 void set_transitive_interfaces(Array<Klass*>* a) {
354 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
355 _transitive_interfaces = a;
356 }
357
358 private:
359 friend class fieldDescriptor;
360 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
361
362 public:
363 int field_offset (int index) const { return field(index)->offset(); }
364 int field_access_flags(int index) const { return field(index)->access_flags(); }
365 Symbol* field_name (int index) const { return field(index)->name(constants()); }
366 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
367
368 // Number of Java declared fields
369 int java_fields_count() const { return (int)_java_fields_count; }
370
371 Array<u2>* fields() const { return _fields; }
372 void set_fields(Array<u2>* f, u2 java_fields_count) {
373 guarantee(_fields == NULL || f == NULL, "Just checking");
374 _fields = f;
375 _java_fields_count = java_fields_count;
376 }
377
378 // inner classes
379 Array<u2>* inner_classes() const { return _inner_classes; }
380 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
381
382 enum InnerClassAttributeOffset {
383 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
384 inner_class_inner_class_info_offset = 0,
385 inner_class_outer_class_info_offset = 1,
386 inner_class_inner_name_offset = 2,
387 inner_class_access_flags_offset = 3,
388 inner_class_next_offset = 4
389 };
390
391 enum EnclosingMethodAttributeOffset {
392 enclosing_method_class_index_offset = 0,
393 enclosing_method_method_index_offset = 1,
394 enclosing_method_attribute_size = 2
395 };
396
397 // method override check
398 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
399
400 // package
401 bool is_same_class_package(Klass* class2);
402 bool is_same_class_package(oop classloader2, Symbol* classname2);
403 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
404
405 // find an enclosing class (defined where original code was, in jvm.cpp!)
406 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
407 instanceKlassHandle self(THREAD, this);
408 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
409 }
410 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
411 bool* inner_is_member, TRAPS);
412
413 // tell if two classes have the same enclosing class (at package level)
414 bool is_same_package_member(Klass* class2, TRAPS) {
415 instanceKlassHandle self(THREAD, this);
416 return is_same_package_member_impl(self, class2, THREAD);
417 }
418 static bool is_same_package_member_impl(instanceKlassHandle self,
419 Klass* class2, TRAPS);
420
421 // initialization state
422 bool is_loaded() const { return _init_state >= loaded; }
423 bool is_linked() const { return _init_state >= linked; }
424 bool is_initialized() const { return _init_state == fully_initialized; }
425 bool is_not_initialized() const { return _init_state < being_initialized; }
426 bool is_being_initialized() const { return _init_state == being_initialized; }
427 bool is_in_error_state() const { return _init_state == initialization_error; }
428 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
429 ClassState init_state() { return (ClassState)_init_state; }
430 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
431
432 // defineClass specified verification
433 bool should_verify_class() const {
434 return (_misc_flags & _misc_should_verify_class) != 0;
435 }
436 void set_should_verify_class(bool value) {
437 if (value) {
438 _misc_flags |= _misc_should_verify_class;
439 } else {
440 _misc_flags &= ~_misc_should_verify_class;
441 }
442 }
443
444 // marking
445 bool is_marked_dependent() const { return _is_marked_dependent; }
446 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
447
448 bool has_unloaded_dependent() const { return _has_unloaded_dependent; }
449 void set_has_unloaded_dependent(bool value) { _has_unloaded_dependent = value; }
450
451 // initialization (virtuals from Klass)
452 bool should_be_initialized() const; // means that initialize should be called
453 void initialize(TRAPS);
454 void link_class(TRAPS);
455 bool link_class_or_fail(TRAPS); // returns false on failure
456 void unlink_class();
457 void rewrite_class(TRAPS);
458 void link_methods(TRAPS);
459 Method* class_initializer();
460
461 // set the class to initialized if no static initializer is present
462 void eager_initialize(Thread *thread);
463
464 // reference type
465 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
466 void set_reference_type(ReferenceType t) {
467 assert(t == (u1)t, "overflow");
468 _reference_type = (u1)t;
469 }
470
471 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
472
473 // find local field, returns true if found
474 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
475 // find field in direct superinterfaces, returns the interface in which the field is defined
476 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
477 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
478 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
479 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
480 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
481
482 // find a non-static or static field given its offset within the class.
483 bool contains_field_offset(int offset) {
484 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
485 }
486
487 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
488 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
489
490 // find a local method (returns NULL if not found)
491 Method* find_method(Symbol* name, Symbol* signature) const;
492 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
493 static Method* find_instance_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
494
495 // find a local method index in default_methods (returns -1 if not found)
496 static int find_method_index(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
497
498 // lookup operation (returns NULL if not found)
499 Method* uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
500
501 // lookup a method in all the interfaces that this class implements
502 // (returns NULL if not found)
503 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
504
505 // lookup a method in local defaults then in all interfaces
506 // (returns NULL if not found)
507 Method* lookup_method_in_ordered_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 assert(*hk != NULL, "host klass should always be set if the address is not null");
533 return *hk;
534 }
535 }
536 void set_host_klass(Klass* host) {
537 assert(is_anonymous(), "not anonymous");
538 Klass** addr = (Klass**)adr_host_klass();
539 assert(addr != NULL, "no reversed space");
540 if (addr != NULL) {
541 *addr = host;
542 }
543 }
544 bool is_anonymous() const {
545 return (_misc_flags & _misc_is_anonymous) != 0;
546 }
547 void set_is_anonymous(bool value) {
548 if (value) {
549 _misc_flags |= _misc_is_anonymous;
550 } else {
551 _misc_flags &= ~_misc_is_anonymous;
552 }
553 }
554
555 // Oop that keeps the metadata for this class from being unloaded
556 // in places where the metadata is stored in other places, like nmethods
557 oop klass_holder() const {
558 return is_anonymous() ? java_mirror() : class_loader();
559 }
560
561 bool is_contended() const {
562 return (_misc_flags & _misc_is_contended) != 0;
563 }
564 void set_is_contended(bool value) {
565 if (value) {
566 _misc_flags |= _misc_is_contended;
567 } else {
568 _misc_flags &= ~_misc_is_contended;
569 }
570 }
571
572 // source file name
573 Symbol* source_file_name() const {
574 return (_source_file_name_index == 0) ?
575 (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
576 }
577 u2 source_file_name_index() const {
578 return _source_file_name_index;
579 }
580 void set_source_file_name_index(u2 sourcefile_index) {
581 _source_file_name_index = sourcefile_index;
582 }
583
584 // minor and major version numbers of class file
585 u2 minor_version() const { return _minor_version; }
586 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
587 u2 major_version() const { return _major_version; }
588 void set_major_version(u2 major_version) { _major_version = major_version; }
589
590 // source debug extension
591 char* source_debug_extension() const { return _source_debug_extension; }
592 void set_source_debug_extension(char* array, int length);
593
594 // symbol unloading support (refcount already added)
595 Symbol* array_name() { return _array_name; }
596 void set_array_name(Symbol* name) { assert(_array_name == NULL || name == NULL, "name already created"); _array_name = name; }
597
598 // nonstatic oop-map blocks
599 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
600 return oop_map_count * OopMapBlock::size_in_words();
601 }
602 unsigned int nonstatic_oop_map_count() const {
603 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
604 }
605 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
606 void set_nonstatic_oop_map_size(int words) {
607 _nonstatic_oop_map_size = words;
608 }
609
610 // RedefineClasses() support for previous versions:
611 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
612 int emcp_method_count);
613 // If the _previous_versions array is non-NULL, then this klass
614 // has been redefined at least once even if we aren't currently
615 // tracking a previous version.
616 bool has_been_redefined() const { return _previous_versions != NULL; }
617 bool has_previous_version() const;
618 void init_previous_versions() {
619 _previous_versions = NULL;
620 }
621 GrowableArray<PreviousVersionNode *>* previous_versions() const {
622 return _previous_versions;
623 }
624
625 static void purge_previous_versions(InstanceKlass* ik);
626
627 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
628 void set_cached_class_file(JvmtiCachedClassFileData *data) {
629 _cached_class_file = data;
630 }
631 JvmtiCachedClassFileData * get_cached_class_file() { return _cached_class_file; }
632 jint get_cached_class_file_len();
633 unsigned char * get_cached_class_file_bytes();
634
635 // JVMTI: Support for caching of field indices, types, and offsets
636 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
637 _jvmti_cached_class_field_map = descriptor;
638 }
639 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
640 return _jvmti_cached_class_field_map;
641 }
642
643 bool has_default_methods() const {
644 return (_misc_flags & _misc_has_default_methods) != 0;
645 }
646 void set_has_default_methods(bool b) {
647 if (b) {
648 _misc_flags |= _misc_has_default_methods;
649 } else {
650 _misc_flags &= ~_misc_has_default_methods;
651 }
652 }
653
654 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
655 inline u2 next_method_idnum();
656 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
657
658 // generics support
659 Symbol* generic_signature() const {
660 return (_generic_signature_index == 0) ?
661 (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
662 }
663 u2 generic_signature_index() const {
664 return _generic_signature_index;
665 }
666 void set_generic_signature_index(u2 sig_index) {
667 _generic_signature_index = sig_index;
668 }
669
670 u2 enclosing_method_data(int offset);
671 u2 enclosing_method_class_index() {
672 return enclosing_method_data(enclosing_method_class_index_offset);
673 }
674 u2 enclosing_method_method_index() {
675 return enclosing_method_data(enclosing_method_method_index_offset);
676 }
677 void set_enclosing_method_indices(u2 class_index,
678 u2 method_index);
679
680 // jmethodID support
681 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
682 methodHandle method_h);
683 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
684 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
685 jmethodID* to_dealloc_id_p,
686 jmethodID** to_dealloc_jmeths_p);
687 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
688 size_t *length_p, jmethodID* id_p);
689 jmethodID jmethod_id_or_null(Method* method);
690
691 // annotations support
692 Annotations* annotations() const { return _annotations; }
693 void set_annotations(Annotations* anno) { _annotations = anno; }
694
695 AnnotationArray* class_annotations() const {
696 return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
697 }
698 Array<AnnotationArray*>* fields_annotations() const {
699 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
700 }
701 AnnotationArray* class_type_annotations() const {
702 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
703 }
704 Array<AnnotationArray*>* fields_type_annotations() const {
705 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
706 }
707 // allocation
708 instanceOop allocate_instance(TRAPS);
709
710 // additional member function to return a handle
711 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
712
713 objArrayOop allocate_objArray(int n, int length, TRAPS);
714 // Helper function
715 static instanceOop register_finalizer(instanceOop i, TRAPS);
716
717 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
718 // if not, throw either an Error or an Exception.
719 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
720
721 // initialization
722 void call_class_initializer(TRAPS);
723 void set_initialization_state_and_notify(ClassState state, TRAPS);
724
725 // OopMapCache support
726 OopMapCache* oop_map_cache() { return _oop_map_cache; }
727 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
728 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
729
730 // JNI identifier support (for static fields - for jni performance)
731 JNIid* jni_ids() { return _jni_ids; }
732 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
733 JNIid* jni_id_for(int offset);
734
735 // maintenance of deoptimization dependencies
736 int mark_dependent_nmethods(DepChange& changes);
737 void add_dependent_nmethod(nmethod* nm);
738 void remove_dependent_nmethod(nmethod* nm);
739
740 // On-stack replacement support
741 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
742 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
743 void add_osr_nmethod(nmethod* n);
744 void remove_osr_nmethod(nmethod* n);
745 nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
746
747 // Breakpoint support (see methods on Method* for details)
748 BreakpointInfo* breakpoints() const { return _breakpoints; };
749 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
750
751 // support for stub routines
752 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
753 TRACE_DEFINE_OFFSET;
754 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
755
756 // subclass/subinterface checks
757 bool implements_interface(Klass* k) const;
758 bool is_same_or_direct_interface(Klass* k) const;
759
760 #ifdef ASSERT
761 // check whether this class or one of its superclasses was redefined
762 bool has_redefined_this_or_super() const;
763 #endif
764
765 // Access to the implementor of an interface.
766 Klass* implementor() const
767 {
768 Klass** k = adr_implementor();
769 if (k == NULL) {
770 return NULL;
771 } else {
772 return *k;
773 }
774 }
775
776 void set_implementor(Klass* k) {
777 assert(is_interface(), "not interface");
778 Klass** addr = adr_implementor();
779 assert(addr != NULL, "null addr");
780 if (addr != NULL) {
781 *addr = k;
782 }
783 }
784
785 int nof_implementors() const {
786 Klass* k = implementor();
787 if (k == NULL) {
788 return 0;
789 } else if (k != this) {
790 return 1;
791 } else {
792 return 2;
793 }
794 }
795
796 void add_implementor(Klass* k); // k is a new class that implements this interface
797 void init_implementor(); // initialize
798
799 // link this class into the implementors list of every interface it implements
800 void process_interfaces(Thread *thread);
801
802 // virtual operations from Klass
803 bool is_leaf_class() const { return _subklass == NULL; }
804 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
805 bool compute_is_subtype_of(Klass* k);
806 bool can_be_primary_super_slow() const;
807 int oop_size(oop obj) const { return size_helper(); }
808 bool oop_is_instance_slow() const { return true; }
809
810 // Iterators
811 void do_local_static_fields(FieldClosure* cl);
812 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
813 void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
814
815 void methods_do(void f(Method* method));
816 void array_klasses_do(void f(Klass* k));
817 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
818 bool super_types_do(SuperTypeClosure* blk);
819
820 // Casting from Klass*
821 static InstanceKlass* cast(Klass* k) {
822 assert(k == NULL || k->is_klass(), "must be");
823 assert(k == NULL || k->oop_is_instance(), "cast to InstanceKlass");
824 return (InstanceKlass*) k;
825 }
826
827 InstanceKlass* java_super() const {
828 return (super() == NULL) ? NULL : cast(super());
829 }
830
831 // Sizing (in words)
832 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
833
834 static int size(int vtable_length, int itable_length,
835 int nonstatic_oop_map_size,
836 bool is_interface, bool is_anonymous) {
837 return align_object_size(header_size() +
838 align_object_offset(vtable_length) +
839 align_object_offset(itable_length) +
840 ((is_interface || is_anonymous) ?
841 align_object_offset(nonstatic_oop_map_size) :
842 nonstatic_oop_map_size) +
843 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
844 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
845 }
846 int size() const { return size(vtable_length(),
847 itable_length(),
848 nonstatic_oop_map_size(),
849 is_interface(),
850 is_anonymous());
851 }
852 #if INCLUDE_SERVICES
853 virtual void collect_statistics(KlassSizeStats *sz) const;
854 #endif
855
856 static int vtable_start_offset() { return header_size(); }
857 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
858
859 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
860 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
861 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
862
863 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
864
865 address static_field_addr(int offset);
866
867 OopMapBlock* start_of_nonstatic_oop_maps() const {
868 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
869 }
870
871 Klass** end_of_nonstatic_oop_maps() const {
872 return (Klass**)(start_of_nonstatic_oop_maps() +
873 nonstatic_oop_map_count());
874 }
875
876 Klass** adr_implementor() const {
877 if (is_interface()) {
878 return (Klass**)end_of_nonstatic_oop_maps();
879 } else {
880 return NULL;
881 }
882 };
883
884 Klass** adr_host_klass() const {
885 if (is_anonymous()) {
886 Klass** adr_impl = adr_implementor();
887 if (adr_impl != NULL) {
888 return adr_impl + 1;
889 } else {
890 return end_of_nonstatic_oop_maps();
891 }
892 } else {
893 return NULL;
894 }
895 }
896
897 // Use this to return the size of an instance in heap words:
898 int size_helper() const {
899 return layout_helper_to_size_helper(layout_helper());
900 }
901
902 // This bit is initialized in classFileParser.cpp.
903 // It is false under any of the following conditions:
904 // - the class is abstract (including any interface)
905 // - the class has a finalizer (if !RegisterFinalizersAtInit)
906 // - the class size is larger than FastAllocateSizeLimit
907 // - the class is java/lang/Class, which cannot be allocated directly
908 bool can_be_fastpath_allocated() const {
909 return !layout_helper_needs_slow_path(layout_helper());
910 }
911
912 // Java vtable/itable
913 klassVtable* vtable() const; // return new klassVtable wrapper
914 inline Method* method_at_vtable(int index);
915 klassItable* itable() const; // return new klassItable wrapper
916 Method* method_at_itable(Klass* holder, int index, TRAPS);
917
918 #if INCLUDE_JVMTI
919 void adjust_default_methods(Method** old_methods, Method** new_methods,
920 int methods_length, bool* trace_name_printed);
921 #endif // INCLUDE_JVMTI
922
923 // Garbage collection
924 void oop_follow_contents(oop obj);
925 int oop_adjust_pointers(oop obj);
926
927 void clean_implementors_list(BoolObjectClosure* is_alive);
928 void clean_method_data(BoolObjectClosure* is_alive);
929 void clean_dependent_nmethods();
930
931 // Explicit metaspace deallocation of fields
932 // For RedefineClasses and class file parsing errors, we need to deallocate
933 // instanceKlasses and the metadata they point to.
934 void deallocate_contents(ClassLoaderData* loader_data);
935 static void deallocate_methods(ClassLoaderData* loader_data,
936 Array<Method*>* methods);
937 void static deallocate_interfaces(ClassLoaderData* loader_data,
938 Klass* super_klass,
939 Array<Klass*>* local_interfaces,
940 Array<Klass*>* transitive_interfaces);
941
942 // The constant pool is on stack if any of the methods are executing or
943 // referenced by handles.
944 bool on_stack() const { return _constants->on_stack(); }
945
946 // callbacks for actions during class unloading
947 static void notify_unload_class(InstanceKlass* ik);
948 static void release_C_heap_structures(InstanceKlass* ik);
949
950 // Parallel Scavenge and Parallel Old
951 PARALLEL_GC_DECLS
952
953 // Naming
954 const char* signature_name() const;
955
956 // Iterators
957 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
958 return oop_oop_iterate_v(obj, blk);
959 }
960
961 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
962 return oop_oop_iterate_v_m(obj, blk, mr);
963 }
964
965 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
966 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
967 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
968 MemRegion mr);
969
970 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
971 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
972
973 #if INCLUDE_ALL_GCS
974 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
975 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
976
977 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
978 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
979 #endif // INCLUDE_ALL_GCS
980
981 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
982
983 private:
984 // initialization state
985 #ifdef ASSERT
986 void set_init_state(ClassState state);
987 #else
988 void set_init_state(ClassState state) { _init_state = (u1)state; }
989 #endif
990 void set_rewritten() { _misc_flags |= _misc_rewritten; }
991 void set_init_thread(Thread *thread) { _init_thread = thread; }
992
993 // The RedefineClasses() API can cause new method idnums to be needed
994 // which will cause the caches to grow. Safety requires different
995 // cache management logic if the caches can grow instead of just
996 // going from NULL to non-NULL.
997 bool idnum_can_increment() const { return has_been_redefined(); }
998 jmethodID* methods_jmethod_ids_acquire() const
999 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
1000 void release_set_methods_jmethod_ids(jmethodID* jmeths)
1001 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
1002
1003 // Lock during initialization
1004 public:
1005 // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1006 // Must be one per class and it has to be a VM internal object so java code
1007 // cannot lock it (like the mirror).
1008 // It has to be an object not a Mutex because it's held through java calls.
1009 oop init_lock() const;
1010 private:
1011 void fence_and_clear_init_lock();
1012
1013 // Static methods that are used to implement member methods where an exposed this pointer
1014 // is needed due to possible GCs
1015 static bool link_class_impl (instanceKlassHandle this_k, bool throw_verifyerror, TRAPS);
1016 static bool verify_code (instanceKlassHandle this_k, bool throw_verifyerror, TRAPS);
1017 static void initialize_impl (instanceKlassHandle this_k, TRAPS);
1018 static void eager_initialize_impl (instanceKlassHandle this_k);
1019 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_k, ClassState state, TRAPS);
1020 static void call_class_initializer_impl (instanceKlassHandle this_k, TRAPS);
1021 static Klass* array_klass_impl (instanceKlassHandle this_k, bool or_null, int n, TRAPS);
1022 static void do_local_static_fields_impl (instanceKlassHandle this_k, void f(fieldDescriptor* fd, Handle, TRAPS), Handle, TRAPS);
1023 /* jni_id_for_impl for jfieldID only */
1024 static JNIid* jni_id_for_impl (instanceKlassHandle this_k, int offset);
1025
1026 // Returns the array class for the n'th dimension
1027 Klass* array_klass_impl(bool or_null, int n, TRAPS);
1028
1029 // Returns the array class with this class as element type
1030 Klass* array_klass_impl(bool or_null, TRAPS);
1031
1032 // find a local method (returns NULL if not found)
1033 Method* find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const;
1034 static Method* find_method_impl(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
1035
1036 // Free CHeap allocated fields.
1037 void release_C_heap_structures();
1038 public:
1039 // CDS support - remove and restore oops from metadata. Oops are not shared.
1040 virtual void remove_unshareable_info();
1041 virtual void restore_unshareable_info(TRAPS);
1042
1043 // jvm support
1044 jint compute_modifier_flags(TRAPS) const;
1045
1046 // JSR-292 support
1047 MemberNameTable* member_names() { return _member_names; }
1048 void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1049 void add_member_name(int index, Handle member_name);
1050 oop get_member_name(int index);
1051
1052 public:
1053 // JVMTI support
1054 jint jvmti_class_status() const;
1055
1056 public:
1057 // Printing
1058 #ifndef PRODUCT
1059 void print_on(outputStream* st) const;
1060 #endif
1061 void print_value_on(outputStream* st) const;
1062
1063 void oop_print_value_on(oop obj, outputStream* st);
1064
1065 #ifndef PRODUCT
1066 void oop_print_on (oop obj, outputStream* st);
1067
1068 void print_dependent_nmethods(bool verbose = false);
1069 bool is_dependent_nmethod(nmethod* nm);
1070 #endif
1071
1072 const char* internal_name() const;
1073
1074 // Verification
1075 void verify_on(outputStream* st);
1076
1077 void oop_verify_on(oop obj, outputStream* st);
1078 };
1079
1080 inline Method* InstanceKlass::method_at_vtable(int index) {
1081 #ifndef PRODUCT
1082 assert(index >= 0, "valid vtable index");
1083 if (DebugVtables) {
1084 verify_vtable_index(index);
1085 }
1086 #endif
1087 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1088 return ve[index].method();
1089 }
1090
1091 // for adding methods
1092 // UNSET_IDNUM return means no more ids available
1093 inline u2 InstanceKlass::next_method_idnum() {
1094 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1095 return ConstMethod::UNSET_IDNUM; // no more ids available
1096 } else {
1097 return _idnum_allocated_count++;
1098 }
1099 }
1100
1101
1102 /* JNIid class for jfieldIDs only */
1103 class JNIid: public CHeapObj<mtClass> {
1104 friend class VMStructs;
1105 private:
1106 Klass* _holder;
1107 JNIid* _next;
1108 int _offset;
1109 #ifdef ASSERT
1110 bool _is_static_field_id;
1111 #endif
1112
1113 public:
1114 // Accessors
1115 Klass* holder() const { return _holder; }
1116 int offset() const { return _offset; }
1117 JNIid* next() { return _next; }
1118 // Constructor
1119 JNIid(Klass* holder, int offset, JNIid* next);
1120 // Identifier lookup
1121 JNIid* find(int offset);
1122
1123 bool find_local_field(fieldDescriptor* fd) {
1124 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1125 }
1126
1127 static void deallocate(JNIid* id);
1128 // Debugging
1129 #ifdef ASSERT
1130 bool is_static_field_id() const { return _is_static_field_id; }
1131 void set_is_static_field_id() { _is_static_field_id = true; }
1132 #endif
1133 void verify(Klass* holder);
1134 };
1135
1136
1137 // If breakpoints are more numerous than just JVMTI breakpoints,
1138 // consider compressing this data structure.
1139 // It is currently a simple linked list defined in method.hpp.
1140
1141 class BreakpointInfo;
1142
1143
1144 // A collection point for interesting information about the previous
1145 // version(s) of an InstanceKlass. A GrowableArray of PreviousVersionNodes
1146 // is attached to the InstanceKlass as needed. See PreviousVersionWalker below.
1147 class PreviousVersionNode : public CHeapObj<mtClass> {
1148 private:
1149 ConstantPool* _prev_constant_pool;
1150
1151 // If the previous version of the InstanceKlass doesn't have any
1152 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1153 // EMCP methods have been collected, then _prev_EMCP_methods can
1154 // have a length of zero.
1155 GrowableArray<Method*>* _prev_EMCP_methods;
1156
1157 public:
1158 PreviousVersionNode(ConstantPool* prev_constant_pool,
1159 GrowableArray<Method*>* prev_EMCP_methods);
1160 ~PreviousVersionNode();
1161 ConstantPool* prev_constant_pool() const {
1162 return _prev_constant_pool;
1163 }
1164 GrowableArray<Method*>* prev_EMCP_methods() const {
1165 return _prev_EMCP_methods;
1166 }
1167 };
1168
1169
1170 // Helper object for walking previous versions.
1171 class PreviousVersionWalker : public StackObj {
1172 private:
1173 Thread* _thread;
1174 GrowableArray<PreviousVersionNode *>* _previous_versions;
1175 int _current_index;
1176
1177 // A pointer to the current node object so we can handle the deletes.
1178 PreviousVersionNode* _current_p;
1179
1180 // The constant pool handle keeps all the methods in this class from being
1181 // deallocated from the metaspace during class unloading.
1182 constantPoolHandle _current_constant_pool_handle;
1183
1184 public:
1185 PreviousVersionWalker(Thread* thread, InstanceKlass *ik);
1186
1187 // Return the interesting information for the next previous version
1188 // of the klass. Returns NULL if there are no more previous versions.
1189 PreviousVersionNode* next_previous_version();
1190 };
1191
1192
1193 //
1194 // nmethodBucket is used to record dependent nmethods for
1195 // deoptimization. nmethod dependencies are actually <klass, method>
1196 // pairs but we really only care about the klass part for purposes of
1197 // finding nmethods which might need to be deoptimized. Instead of
1198 // recording the method, a count of how many times a particular nmethod
1199 // was recorded is kept. This ensures that any recording errors are
1200 // noticed since an nmethod should be removed as many times are it's
1201 // added.
1202 //
1203 class nmethodBucket: public CHeapObj<mtClass> {
1204 friend class VMStructs;
1205 private:
1206 nmethod* _nmethod;
1207 int _count;
1208 nmethodBucket* _next;
1209
1210 public:
1211 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1212 _nmethod = nmethod;
1213 _next = next;
1214 _count = 1;
1215 }
1216 int count() { return _count; }
1217 int increment() { _count += 1; return _count; }
1218 int decrement();
1219 nmethodBucket* next() { return _next; }
1220 void set_next(nmethodBucket* b) { _next = b; }
1221 nmethod* get_nmethod() { return _nmethod; }
1222 };
1223
1224 // An iterator that's used to access the inner classes indices in the
1225 // InstanceKlass::_inner_classes array.
1226 class InnerClassesIterator : public StackObj {
1227 private:
1228 Array<jushort>* _inner_classes;
1229 int _length;
1230 int _idx;
1231 public:
1232
1233 InnerClassesIterator(instanceKlassHandle k) {
1234 _inner_classes = k->inner_classes();
1235 if (k->inner_classes() != NULL) {
1236 _length = _inner_classes->length();
1237 // The inner class array's length should be the multiple of
1238 // inner_class_next_offset if it only contains the InnerClasses
1239 // attribute data, or it should be
1240 // n*inner_class_next_offset+enclosing_method_attribute_size
1241 // if it also contains the EnclosingMethod data.
1242 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1243 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1244 "just checking");
1245 // Remove the enclosing_method portion if exists.
1246 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1247 _length -= InstanceKlass::enclosing_method_attribute_size;
1248 }
1249 } else {
1250 _length = 0;
1251 }
1252 _idx = 0;
1253 }
1254
1255 int length() const {
1256 return _length;
1257 }
1258
1259 void next() {
1260 _idx += InstanceKlass::inner_class_next_offset;
1261 }
1262
1263 bool done() const {
1264 return (_idx >= _length);
1265 }
1266
1267 u2 inner_class_info_index() const {
1268 return _inner_classes->at(
1269 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1270 }
1271
1272 void set_inner_class_info_index(u2 index) {
1273 _inner_classes->at_put(
1274 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1275 }
1276
1277 u2 outer_class_info_index() const {
1278 return _inner_classes->at(
1279 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1280 }
1281
1282 void set_outer_class_info_index(u2 index) {
1283 _inner_classes->at_put(
1284 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1285 }
1286
1287 u2 inner_name_index() const {
1288 return _inner_classes->at(
1289 _idx + InstanceKlass::inner_class_inner_name_offset);
1290 }
1291
1292 void set_inner_name_index(u2 index) {
1293 _inner_classes->at_put(
1294 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1295 }
1296
1297 u2 inner_access_flags() const {
1298 return _inner_classes->at(
1299 _idx + InstanceKlass::inner_class_access_flags_offset);
1300 }
1301 };
1302
1303 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP