Tue, 05 Mar 2013 18:03:36 -0800
8008750: [partfait] Null pointer deference in hotspot/src/share/vm/oops/instanceKlass.hpp
Summary: fix null pointer
Reviewed-by: kvn, coleenp
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
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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).
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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23 */
25 #ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP
26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
28 #include "classfile/classLoaderData.hpp"
29 #include "oops/annotations.hpp"
30 #include "oops/constMethod.hpp"
31 #include "oops/fieldInfo.hpp"
32 #include "oops/instanceOop.hpp"
33 #include "oops/klassVtable.hpp"
34 #include "runtime/atomic.hpp"
35 #include "runtime/handles.hpp"
36 #include "runtime/os.hpp"
37 #include "utilities/accessFlags.hpp"
38 #include "utilities/bitMap.inline.hpp"
39 #include "utilities/macros.hpp"
41 // An InstanceKlass is the VM level representation of a Java class.
42 // It contains all information needed for at class at execution runtime.
44 // InstanceKlass layout:
45 // [C++ vtbl pointer ] Klass
46 // [subtype cache ] Klass
47 // [instance size ] Klass
48 // [java mirror ] Klass
49 // [super ] Klass
50 // [access_flags ] Klass
51 // [name ] Klass
52 // [first subklass ] Klass
53 // [next sibling ] Klass
54 // [array klasses ]
55 // [methods ]
56 // [local interfaces ]
57 // [transitive interfaces ]
58 // [fields ]
59 // [constants ]
60 // [class loader ]
61 // [protection domain ]
62 // [signers ]
63 // [source file name ]
64 // [inner classes ]
65 // [static field size ]
66 // [nonstatic field size ]
67 // [static oop fields size ]
68 // [nonstatic oop maps size ]
69 // [has finalize method ]
70 // [deoptimization mark bit ]
71 // [initialization state ]
72 // [initializing thread ]
73 // [Java vtable length ]
74 // [oop map cache (stack maps) ]
75 // [EMBEDDED Java vtable ] size in words = vtable_len
76 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
77 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
78 // indicating where oops are located in instances of this klass.
79 // [EMBEDDED implementor of the interface] only exist for interface
80 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled)
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;
94 // This is used in iterators below.
95 class FieldClosure: public StackObj {
96 public:
97 virtual void do_field(fieldDescriptor* fd) = 0;
98 };
100 #ifndef PRODUCT
101 // Print fields.
102 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
103 class FieldPrinter: public FieldClosure {
104 oop _obj;
105 outputStream* _st;
106 public:
107 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
108 void do_field(fieldDescriptor* fd);
109 };
110 #endif // !PRODUCT
112 // ValueObjs embedded in klass. Describes where oops are located in instances of
113 // this klass.
114 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
115 public:
116 // Byte offset of the first oop mapped by this block.
117 int offset() const { return _offset; }
118 void set_offset(int offset) { _offset = offset; }
120 // Number of oops in this block.
121 uint count() const { return _count; }
122 void set_count(uint count) { _count = count; }
124 // sizeof(OopMapBlock) in HeapWords.
125 static const int size_in_words() {
126 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
127 LogHeapWordSize;
128 }
130 private:
131 int _offset;
132 uint _count;
133 };
135 class InstanceKlass: public Klass {
136 friend class VMStructs;
137 friend class ClassFileParser;
138 friend class CompileReplay;
140 protected:
141 // Constructor
142 InstanceKlass(int vtable_len,
143 int itable_len,
144 int static_field_size,
145 int nonstatic_oop_map_size,
146 ReferenceType rt,
147 AccessFlags access_flags,
148 bool is_anonymous);
149 public:
150 static Klass* allocate_instance_klass(ClassLoaderData* loader_data,
151 int vtable_len,
152 int itable_len,
153 int static_field_size,
154 int nonstatic_oop_map_size,
155 ReferenceType rt,
156 AccessFlags access_flags,
157 Symbol* name,
158 Klass* super_klass,
159 bool is_anonymous,
160 TRAPS);
162 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
164 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
165 // of the class loading & initialization procedure, and the use of the states.
166 enum ClassState {
167 allocated, // allocated (but not yet linked)
168 loaded, // loaded and inserted in class hierarchy (but not linked yet)
169 linked, // successfully linked/verified (but not initialized yet)
170 being_initialized, // currently running class initializer
171 fully_initialized, // initialized (successfull final state)
172 initialization_error // error happened during initialization
173 };
175 static int number_of_instance_classes() { return _total_instanceKlass_count; }
177 private:
178 static volatile int _total_instanceKlass_count;
180 protected:
181 // Protection domain.
182 oop _protection_domain;
183 // Class signers.
184 objArrayOop _signers;
185 // Initialization lock. Must be one per class and it has to be a VM internal
186 // object so java code cannot lock it (like the mirror)
187 // It has to be an object not a Mutex because it's held through java calls.
188 volatile oop _init_lock;
190 // Annotations for this class
191 Annotations* _annotations;
192 // Array classes holding elements of this class.
193 Klass* _array_klasses;
194 // Constant pool for this class.
195 ConstantPool* _constants;
196 // The InnerClasses attribute and EnclosingMethod attribute. The
197 // _inner_classes is an array of shorts. If the class has InnerClasses
198 // attribute, then the _inner_classes array begins with 4-tuples of shorts
199 // [inner_class_info_index, outer_class_info_index,
200 // inner_name_index, inner_class_access_flags] for the InnerClasses
201 // attribute. If the EnclosingMethod attribute exists, it occupies the
202 // last two shorts [class_index, method_index] of the array. If only
203 // the InnerClasses attribute exists, the _inner_classes array length is
204 // number_of_inner_classes * 4. If the class has both InnerClasses
205 // and EnclosingMethod attributes the _inner_classes array length is
206 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
207 Array<jushort>* _inner_classes;
209 // Name of source file containing this klass, NULL if not specified.
210 Symbol* _source_file_name;
211 // the source debug extension for this klass, NULL if not specified.
212 // Specified as UTF-8 string without terminating zero byte in the classfile,
213 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
214 char* _source_debug_extension;
215 // Generic signature, or null if none.
216 Symbol* _generic_signature;
217 // Array name derived from this class which needs unreferencing
218 // if this class is unloaded.
219 Symbol* _array_name;
221 // Number of heapOopSize words used by non-static fields in this klass
222 // (including inherited fields but after header_size()).
223 int _nonstatic_field_size;
224 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
225 u2 _static_oop_field_count;// number of static oop fields in this klass
226 u2 _java_fields_count; // The number of declared Java fields
227 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
229 // _is_marked_dependent can be set concurrently, thus cannot be part of the
230 // _misc_flags.
231 bool _is_marked_dependent; // used for marking during flushing and deoptimization
233 enum {
234 _misc_rewritten = 1 << 0, // methods rewritten.
235 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
236 _misc_should_verify_class = 1 << 2, // allow caching of preverification
237 _misc_is_anonymous = 1 << 3, // has embedded _inner_classes field
238 _misc_is_contended = 1 << 4, // marked with contended annotation
239 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods
240 };
241 u2 _misc_flags;
242 u2 _minor_version; // minor version number of class file
243 u2 _major_version; // major version number of class file
244 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
245 int _vtable_len; // length of Java vtable (in words)
246 int _itable_len; // length of Java itable (in words)
247 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
248 JNIid* _jni_ids; // First JNI identifier for static fields in this class
249 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
250 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
251 nmethodBucket* _dependencies; // list of dependent nmethods
252 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
253 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
254 // Array of interesting part(s) of the previous version(s) of this
255 // InstanceKlass. See PreviousVersionWalker below.
256 GrowableArray<PreviousVersionNode *>* _previous_versions;
257 // JVMTI fields can be moved to their own structure - see 6315920
258 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH
259 jint _cached_class_file_len; // JVMTI: length of above
261 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
263 // Class states are defined as ClassState (see above).
264 // Place the _init_state here to utilize the unused 2-byte after
265 // _idnum_allocated_count.
266 u1 _init_state; // state of class
267 u1 _reference_type; // reference type
270 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
272 // Method array.
273 Array<Method*>* _methods;
274 // Interface (Klass*s) this class declares locally to implement.
275 Array<Klass*>* _local_interfaces;
276 // Interface (Klass*s) this class implements transitively.
277 Array<Klass*>* _transitive_interfaces;
278 // Int array containing the original order of method in the class file (for JVMTI).
279 Array<int>* _method_ordering;
280 // Instance and static variable information, starts with 6-tuples of shorts
281 // [access, name index, sig index, initval index, low_offset, high_offset]
282 // for all fields, followed by the generic signature data at the end of
283 // the array. Only fields with generic signature attributes have the generic
284 // signature data set in the array. The fields array looks like following:
285 //
286 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
287 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
288 // ...
289 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
290 // [generic signature index]
291 // [generic signature index]
292 // ...
293 Array<u2>* _fields;
295 // embedded Java vtable follows here
296 // embedded Java itables follows here
297 // embedded static fields follows here
298 // embedded nonstatic oop-map blocks follows here
299 // embedded implementor of this interface follows here
300 // The embedded implementor only exists if the current klass is an
301 // iterface. The possible values of the implementor fall into following
302 // three cases:
303 // NULL: no implementor.
304 // A Klass* that's not itself: one implementor.
305 // Itsef: more than one implementors.
306 // embedded host klass follows here
307 // The embedded host klass only exists in an anonymous class for
308 // dynamic language support (JSR 292 enabled). The host class grants
309 // its access privileges to this class also. The host class is either
310 // named, or a previously loaded anonymous class. A non-anonymous class
311 // or an anonymous class loaded through normal classloading does not
312 // have this embedded field.
313 //
315 friend class SystemDictionary;
317 public:
318 bool has_nonstatic_fields() const {
319 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
320 }
321 void set_has_nonstatic_fields(bool b) {
322 if (b) {
323 _misc_flags |= _misc_has_nonstatic_fields;
324 } else {
325 _misc_flags &= ~_misc_has_nonstatic_fields;
326 }
327 }
329 // field sizes
330 int nonstatic_field_size() const { return _nonstatic_field_size; }
331 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
333 int static_field_size() const { return _static_field_size; }
334 void set_static_field_size(int size) { _static_field_size = size; }
336 int static_oop_field_count() const { return (int)_static_oop_field_count; }
337 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
339 // Java vtable
340 int vtable_length() const { return _vtable_len; }
341 void set_vtable_length(int len) { _vtable_len = len; }
343 // Java itable
344 int itable_length() const { return _itable_len; }
345 void set_itable_length(int len) { _itable_len = len; }
347 // array klasses
348 Klass* array_klasses() const { return _array_klasses; }
349 void set_array_klasses(Klass* k) { _array_klasses = k; }
351 // methods
352 Array<Method*>* methods() const { return _methods; }
353 void set_methods(Array<Method*>* a) { _methods = a; }
354 Method* method_with_idnum(int idnum);
356 // method ordering
357 Array<int>* method_ordering() const { return _method_ordering; }
358 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
360 // interfaces
361 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
362 void set_local_interfaces(Array<Klass*>* a) {
363 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
364 _local_interfaces = a; }
365 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
366 void set_transitive_interfaces(Array<Klass*>* a) {
367 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
368 _transitive_interfaces = a; }
370 private:
371 friend class fieldDescriptor;
372 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
374 public:
375 int field_offset (int index) const { return field(index)->offset(); }
376 int field_access_flags(int index) const { return field(index)->access_flags(); }
377 Symbol* field_name (int index) const { return field(index)->name(constants()); }
378 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
380 // Number of Java declared fields
381 int java_fields_count() const { return (int)_java_fields_count; }
383 Array<u2>* fields() const { return _fields; }
385 void set_fields(Array<u2>* f, u2 java_fields_count) {
386 guarantee(_fields == NULL || f == NULL, "Just checking");
387 _fields = f;
388 _java_fields_count = java_fields_count;
389 }
391 // inner classes
392 Array<u2>* inner_classes() const { return _inner_classes; }
393 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
395 enum InnerClassAttributeOffset {
396 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
397 inner_class_inner_class_info_offset = 0,
398 inner_class_outer_class_info_offset = 1,
399 inner_class_inner_name_offset = 2,
400 inner_class_access_flags_offset = 3,
401 inner_class_next_offset = 4
402 };
404 enum EnclosingMethodAttributeOffset {
405 enclosing_method_class_index_offset = 0,
406 enclosing_method_method_index_offset = 1,
407 enclosing_method_attribute_size = 2
408 };
410 // method override check
411 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
413 // package
414 bool is_same_class_package(Klass* class2);
415 bool is_same_class_package(oop classloader2, Symbol* classname2);
416 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
418 // find an enclosing class (defined where original code was, in jvm.cpp!)
419 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
420 instanceKlassHandle self(THREAD, this);
421 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
422 }
423 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
424 bool* inner_is_member, TRAPS);
426 // tell if two classes have the same enclosing class (at package level)
427 bool is_same_package_member(Klass* class2, TRAPS) {
428 instanceKlassHandle self(THREAD, this);
429 return is_same_package_member_impl(self, class2, THREAD);
430 }
431 static bool is_same_package_member_impl(instanceKlassHandle self,
432 Klass* class2, TRAPS);
434 // initialization state
435 bool is_loaded() const { return _init_state >= loaded; }
436 bool is_linked() const { return _init_state >= linked; }
437 bool is_initialized() const { return _init_state == fully_initialized; }
438 bool is_not_initialized() const { return _init_state < being_initialized; }
439 bool is_being_initialized() const { return _init_state == being_initialized; }
440 bool is_in_error_state() const { return _init_state == initialization_error; }
441 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
442 ClassState init_state() { return (ClassState)_init_state; }
443 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
445 // defineClass specified verification
446 bool should_verify_class() const {
447 return (_misc_flags & _misc_should_verify_class) != 0;
448 }
449 void set_should_verify_class(bool value) {
450 if (value) {
451 _misc_flags |= _misc_should_verify_class;
452 } else {
453 _misc_flags &= ~_misc_should_verify_class;
454 }
455 }
457 // marking
458 bool is_marked_dependent() const { return _is_marked_dependent; }
459 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
461 // initialization (virtuals from Klass)
462 bool should_be_initialized() const; // means that initialize should be called
463 void initialize(TRAPS);
464 void link_class(TRAPS);
465 bool link_class_or_fail(TRAPS); // returns false on failure
466 void unlink_class();
467 void rewrite_class(TRAPS);
468 void link_methods(TRAPS);
469 Method* class_initializer();
471 // set the class to initialized if no static initializer is present
472 void eager_initialize(Thread *thread);
474 // reference type
475 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
476 void set_reference_type(ReferenceType t) {
477 assert(t == (u1)t, "overflow");
478 _reference_type = (u1)t;
479 }
481 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
483 // find local field, returns true if found
484 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
485 // find field in direct superinterfaces, returns the interface in which the field is defined
486 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
487 // find field 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, fieldDescriptor* fd) const;
489 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
490 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
492 // find a non-static or static field given its offset within the class.
493 bool contains_field_offset(int offset) {
494 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
495 }
497 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
498 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
500 // find a local method (returns NULL if not found)
501 Method* find_method(Symbol* name, Symbol* signature) const;
502 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
504 // lookup operation (returns NULL if not found)
505 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const;
507 // lookup a method in all the interfaces that this class implements
508 // (returns NULL if not found)
509 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature) const;
511 // Find method indices by name. If a method with the specified name is
512 // found the index to the first method is returned, and 'end' is filled in
513 // with the index of first non-name-matching method. If no method is found
514 // -1 is returned.
515 int find_method_by_name(Symbol* name, int* end);
516 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
518 // constant pool
519 ConstantPool* constants() const { return _constants; }
520 void set_constants(ConstantPool* c) { _constants = c; }
522 // protection domain
523 oop protection_domain() { return _protection_domain; }
524 void set_protection_domain(oop pd) { klass_oop_store(&_protection_domain, pd); }
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 }
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 }
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 }
571 // signers
572 objArrayOop signers() const { return _signers; }
573 void set_signers(objArrayOop s) { klass_oop_store((oop*)&_signers, s); }
575 // source file name
576 Symbol* source_file_name() const { return _source_file_name; }
577 void set_source_file_name(Symbol* n);
579 // minor and major version numbers of class file
580 u2 minor_version() const { return _minor_version; }
581 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
582 u2 major_version() const { return _major_version; }
583 void set_major_version(u2 major_version) { _major_version = major_version; }
585 // source debug extension
586 char* source_debug_extension() const { return _source_debug_extension; }
587 void set_source_debug_extension(char* array, int length);
589 // symbol unloading support (refcount already added)
590 Symbol* array_name() { return _array_name; }
591 void set_array_name(Symbol* name) { assert(_array_name == NULL, "name already created"); _array_name = name; }
593 // nonstatic oop-map blocks
594 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
595 return oop_map_count * OopMapBlock::size_in_words();
596 }
597 unsigned int nonstatic_oop_map_count() const {
598 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
599 }
600 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
601 void set_nonstatic_oop_map_size(int words) {
602 _nonstatic_oop_map_size = words;
603 }
605 // RedefineClasses() support for previous versions:
606 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
607 int emcp_method_count);
608 // If the _previous_versions array is non-NULL, then this klass
609 // has been redefined at least once even if we aren't currently
610 // tracking a previous version.
611 bool has_been_redefined() const { return _previous_versions != NULL; }
612 bool has_previous_version() const;
613 void init_previous_versions() {
614 _previous_versions = NULL;
615 }
616 GrowableArray<PreviousVersionNode *>* previous_versions() const {
617 return _previous_versions;
618 }
620 static void purge_previous_versions(InstanceKlass* ik);
622 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
623 void set_cached_class_file(unsigned char *class_file_bytes,
624 jint class_file_len) { _cached_class_file_len = class_file_len;
625 _cached_class_file_bytes = class_file_bytes; }
626 jint get_cached_class_file_len() { return _cached_class_file_len; }
627 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; }
629 // JVMTI: Support for caching of field indices, types, and offsets
630 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
631 _jvmti_cached_class_field_map = descriptor;
632 }
633 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
634 return _jvmti_cached_class_field_map;
635 }
637 bool has_default_methods() const {
638 return (_misc_flags & _misc_has_default_methods) != 0;
639 }
640 void set_has_default_methods(bool b) {
641 if (b) {
642 _misc_flags |= _misc_has_default_methods;
643 } else {
644 _misc_flags &= ~_misc_has_default_methods;
645 }
646 }
648 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
649 inline u2 next_method_idnum();
650 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
652 // generics support
653 Symbol* generic_signature() const { return _generic_signature; }
654 void set_generic_signature(Symbol* sig) { _generic_signature = sig; }
656 u2 enclosing_method_data(int offset);
657 u2 enclosing_method_class_index() {
658 return enclosing_method_data(enclosing_method_class_index_offset);
659 }
660 u2 enclosing_method_method_index() {
661 return enclosing_method_data(enclosing_method_method_index_offset);
662 }
663 void set_enclosing_method_indices(u2 class_index,
664 u2 method_index);
666 // jmethodID support
667 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
668 methodHandle method_h);
669 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
670 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
671 jmethodID* to_dealloc_id_p,
672 jmethodID** to_dealloc_jmeths_p);
673 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
674 size_t *length_p, jmethodID* id_p);
675 jmethodID jmethod_id_or_null(Method* method);
677 // cached itable index support
678 void set_cached_itable_index(size_t idnum, int index);
679 int cached_itable_index(size_t idnum);
681 // annotations support
682 Annotations* annotations() const { return _annotations; }
683 void set_annotations(Annotations* anno) { _annotations = anno; }
685 AnnotationArray* class_annotations() const {
686 return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
687 }
688 Array<AnnotationArray*>* fields_annotations() const {
689 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
690 }
691 AnnotationArray* class_type_annotations() const {
692 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
693 }
694 Array<AnnotationArray*>* fields_type_annotations() const {
695 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
696 }
697 // allocation
698 instanceOop allocate_instance(TRAPS);
700 // additional member function to return a handle
701 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
703 objArrayOop allocate_objArray(int n, int length, TRAPS);
704 // Helper function
705 static instanceOop register_finalizer(instanceOop i, TRAPS);
707 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
708 // if not, throw either an Error or an Exception.
709 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
711 // initialization
712 void call_class_initializer(TRAPS);
713 void set_initialization_state_and_notify(ClassState state, TRAPS);
715 // OopMapCache support
716 OopMapCache* oop_map_cache() { return _oop_map_cache; }
717 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
718 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
720 // JNI identifier support (for static fields - for jni performance)
721 JNIid* jni_ids() { return _jni_ids; }
722 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
723 JNIid* jni_id_for(int offset);
725 // maintenance of deoptimization dependencies
726 int mark_dependent_nmethods(DepChange& changes);
727 void add_dependent_nmethod(nmethod* nm);
728 void remove_dependent_nmethod(nmethod* nm);
730 // On-stack replacement support
731 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
732 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
733 void add_osr_nmethod(nmethod* n);
734 void remove_osr_nmethod(nmethod* n);
735 nmethod* lookup_osr_nmethod(Method* const m, int bci, int level, bool match_level) const;
737 // Breakpoint support (see methods on Method* for details)
738 BreakpointInfo* breakpoints() const { return _breakpoints; };
739 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
741 // support for stub routines
742 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
743 TRACE_DEFINE_OFFSET;
744 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
746 // subclass/subinterface checks
747 bool implements_interface(Klass* k) const;
749 // Access to the implementor of an interface.
750 Klass* implementor() const
751 {
752 Klass** k = adr_implementor();
753 if (k == NULL) {
754 return NULL;
755 } else {
756 return *k;
757 }
758 }
760 void set_implementor(Klass* k) {
761 assert(is_interface(), "not interface");
762 Klass** addr = adr_implementor();
763 assert(addr != NULL, "null addr");
764 if (addr != NULL) {
765 *addr = k;
766 }
767 }
769 int nof_implementors() const {
770 Klass* k = implementor();
771 if (k == NULL) {
772 return 0;
773 } else if (k != this) {
774 return 1;
775 } else {
776 return 2;
777 }
778 }
780 void add_implementor(Klass* k); // k is a new class that implements this interface
781 void init_implementor(); // initialize
783 // link this class into the implementors list of every interface it implements
784 void process_interfaces(Thread *thread);
786 // virtual operations from Klass
787 bool is_leaf_class() const { return _subklass == NULL; }
788 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
789 bool compute_is_subtype_of(Klass* k);
790 bool can_be_primary_super_slow() const;
791 int oop_size(oop obj) const { return size_helper(); }
792 bool oop_is_instance_slow() const { return true; }
794 // Iterators
795 void do_local_static_fields(FieldClosure* cl);
796 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
797 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
799 void methods_do(void f(Method* method));
800 void array_klasses_do(void f(Klass* k));
801 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
802 void with_array_klasses_do(void f(Klass* k));
803 bool super_types_do(SuperTypeClosure* blk);
805 // Casting from Klass*
806 static InstanceKlass* cast(Klass* k) {
807 assert(k->is_klass(), "must be");
808 assert(k->oop_is_instance(), "cast to InstanceKlass");
809 return (InstanceKlass*) k;
810 }
812 InstanceKlass* java_super() const {
813 return (super() == NULL) ? NULL : cast(super());
814 }
816 // Sizing (in words)
817 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
819 static int size(int vtable_length, int itable_length,
820 int nonstatic_oop_map_size,
821 bool is_interface, bool is_anonymous) {
822 return align_object_size(header_size() +
823 align_object_offset(vtable_length) +
824 align_object_offset(itable_length) +
825 ((is_interface || is_anonymous) ?
826 align_object_offset(nonstatic_oop_map_size) :
827 nonstatic_oop_map_size) +
828 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
829 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
830 }
831 int size() const { return size(vtable_length(),
832 itable_length(),
833 nonstatic_oop_map_size(),
834 is_interface(),
835 is_anonymous());
836 }
837 #if INCLUDE_SERVICES
838 virtual void collect_statistics(KlassSizeStats *sz) const;
839 #endif
841 static int vtable_start_offset() { return header_size(); }
842 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
844 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
845 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
846 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
848 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
850 address static_field_addr(int offset);
852 OopMapBlock* start_of_nonstatic_oop_maps() const {
853 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
854 }
856 Klass** end_of_nonstatic_oop_maps() const {
857 return (Klass**)(start_of_nonstatic_oop_maps() +
858 nonstatic_oop_map_count());
859 }
861 Klass** adr_implementor() const {
862 if (is_interface()) {
863 return (Klass**)end_of_nonstatic_oop_maps();
864 } else {
865 return NULL;
866 }
867 };
869 Klass** adr_host_klass() const {
870 if (is_anonymous()) {
871 Klass** adr_impl = adr_implementor();
872 if (adr_impl != NULL) {
873 return adr_impl + 1;
874 } else {
875 return end_of_nonstatic_oop_maps();
876 }
877 } else {
878 return NULL;
879 }
880 }
882 // Allocation profiling support
883 juint alloc_size() const { return _alloc_count * size_helper(); }
884 void set_alloc_size(juint n) {}
886 // Use this to return the size of an instance in heap words:
887 int size_helper() const {
888 return layout_helper_to_size_helper(layout_helper());
889 }
891 // This bit is initialized in classFileParser.cpp.
892 // It is false under any of the following conditions:
893 // - the class is abstract (including any interface)
894 // - the class has a finalizer (if !RegisterFinalizersAtInit)
895 // - the class size is larger than FastAllocateSizeLimit
896 // - the class is java/lang/Class, which cannot be allocated directly
897 bool can_be_fastpath_allocated() const {
898 return !layout_helper_needs_slow_path(layout_helper());
899 }
901 // Java vtable/itable
902 klassVtable* vtable() const; // return new klassVtable wrapper
903 inline Method* method_at_vtable(int index);
904 klassItable* itable() const; // return new klassItable wrapper
905 Method* method_at_itable(Klass* holder, int index, TRAPS);
907 // Garbage collection
908 virtual void oops_do(OopClosure* cl);
910 void oop_follow_contents(oop obj);
911 int oop_adjust_pointers(oop obj);
913 void clean_implementors_list(BoolObjectClosure* is_alive);
914 void clean_method_data(BoolObjectClosure* is_alive);
916 // Explicit metaspace deallocation of fields
917 // For RedefineClasses, we need to deallocate instanceKlasses
918 void deallocate_contents(ClassLoaderData* loader_data);
920 // The constant pool is on stack if any of the methods are executing or
921 // referenced by handles.
922 bool on_stack() const { return _constants->on_stack(); }
924 void release_C_heap_structures();
926 // Parallel Scavenge and Parallel Old
927 PARALLEL_GC_DECLS
929 // Naming
930 const char* signature_name() const;
932 // Iterators
933 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
934 return oop_oop_iterate_v(obj, blk);
935 }
937 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
938 return oop_oop_iterate_v_m(obj, blk, mr);
939 }
941 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
942 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
943 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
944 MemRegion mr);
946 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
947 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
949 #if INCLUDE_ALL_GCS
950 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
951 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
953 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
954 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
955 #endif // INCLUDE_ALL_GCS
957 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
958 private:
959 // initialization state
960 #ifdef ASSERT
961 void set_init_state(ClassState state);
962 #else
963 void set_init_state(ClassState state) { _init_state = (u1)state; }
964 #endif
965 void set_rewritten() { _misc_flags |= _misc_rewritten; }
966 void set_init_thread(Thread *thread) { _init_thread = thread; }
968 // The RedefineClasses() API can cause new method idnums to be needed
969 // which will cause the caches to grow. Safety requires different
970 // cache management logic if the caches can grow instead of just
971 // going from NULL to non-NULL.
972 bool idnum_can_increment() const { return has_been_redefined(); }
973 jmethodID* methods_jmethod_ids_acquire() const
974 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
975 void release_set_methods_jmethod_ids(jmethodID* jmeths)
976 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
978 int* methods_cached_itable_indices_acquire() const
979 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
980 void release_set_methods_cached_itable_indices(int* indices)
981 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
983 // Lock during initialization
984 volatile oop init_lock() const;
985 void set_init_lock(oop value) { klass_oop_store(&_init_lock, value); }
986 void fence_and_clear_init_lock(); // after fully_initialized
988 // Offsets for memory management
989 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
990 oop* adr_signers() const { return (oop*)&this->_signers;}
991 oop* adr_init_lock() const { return (oop*)&this->_init_lock;}
993 // Static methods that are used to implement member methods where an exposed this pointer
994 // is needed due to possible GCs
995 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
996 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
997 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
998 static void eager_initialize_impl (instanceKlassHandle this_oop);
999 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
1000 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
1001 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
1002 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
1003 /* jni_id_for_impl for jfieldID only */
1004 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
1006 // Returns the array class for the n'th dimension
1007 Klass* array_klass_impl(bool or_null, int n, TRAPS);
1009 // Returns the array class with this class as element type
1010 Klass* array_klass_impl(bool or_null, TRAPS);
1012 public:
1013 // CDS support - remove and restore oops from metadata. Oops are not shared.
1014 virtual void remove_unshareable_info();
1015 virtual void restore_unshareable_info(TRAPS);
1017 // jvm support
1018 jint compute_modifier_flags(TRAPS) const;
1020 public:
1021 // JVMTI support
1022 jint jvmti_class_status() const;
1024 public:
1025 // Printing
1026 #ifndef PRODUCT
1027 void print_on(outputStream* st) const;
1028 #endif
1029 void print_value_on(outputStream* st) const;
1031 void oop_print_value_on(oop obj, outputStream* st);
1033 #ifndef PRODUCT
1034 void oop_print_on (oop obj, outputStream* st);
1036 void print_dependent_nmethods(bool verbose = false);
1037 bool is_dependent_nmethod(nmethod* nm);
1038 #endif
1040 const char* internal_name() const;
1042 // Verification
1043 void verify_on(outputStream* st);
1045 void oop_verify_on(oop obj, outputStream* st);
1046 };
1048 inline Method* InstanceKlass::method_at_vtable(int index) {
1049 #ifndef PRODUCT
1050 assert(index >= 0, "valid vtable index");
1051 if (DebugVtables) {
1052 verify_vtable_index(index);
1053 }
1054 #endif
1055 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1056 return ve[index].method();
1057 }
1059 // for adding methods
1060 // UNSET_IDNUM return means no more ids available
1061 inline u2 InstanceKlass::next_method_idnum() {
1062 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1063 return ConstMethod::UNSET_IDNUM; // no more ids available
1064 } else {
1065 return _idnum_allocated_count++;
1066 }
1067 }
1070 /* JNIid class for jfieldIDs only */
1071 class JNIid: public CHeapObj<mtClass> {
1072 friend class VMStructs;
1073 private:
1074 Klass* _holder;
1075 JNIid* _next;
1076 int _offset;
1077 #ifdef ASSERT
1078 bool _is_static_field_id;
1079 #endif
1081 public:
1082 // Accessors
1083 Klass* holder() const { return _holder; }
1084 int offset() const { return _offset; }
1085 JNIid* next() { return _next; }
1086 // Constructor
1087 JNIid(Klass* holder, int offset, JNIid* next);
1088 // Identifier lookup
1089 JNIid* find(int offset);
1091 bool find_local_field(fieldDescriptor* fd) {
1092 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1093 }
1095 static void deallocate(JNIid* id);
1096 // Debugging
1097 #ifdef ASSERT
1098 bool is_static_field_id() const { return _is_static_field_id; }
1099 void set_is_static_field_id() { _is_static_field_id = true; }
1100 #endif
1101 void verify(Klass* holder);
1102 };
1105 // If breakpoints are more numerous than just JVMTI breakpoints,
1106 // consider compressing this data structure.
1107 // It is currently a simple linked list defined in method.hpp.
1109 class BreakpointInfo;
1112 // A collection point for interesting information about the previous
1113 // version(s) of an InstanceKlass. This class uses weak references to
1114 // the information so that the information may be collected as needed
1115 // by the system. If the information is shared, then a regular
1116 // reference must be used because a weak reference would be seen as
1117 // collectible. A GrowableArray of PreviousVersionNodes is attached
1118 // to the InstanceKlass as needed. See PreviousVersionWalker below.
1119 class PreviousVersionNode : public CHeapObj<mtClass> {
1120 private:
1121 // A shared ConstantPool is never collected so we'll always have
1122 // a reference to it so we can update items in the cache. We'll
1123 // have a weak reference to a non-shared ConstantPool until all
1124 // of the methods (EMCP or obsolete) have been collected; the
1125 // non-shared ConstantPool becomes collectible at that point.
1126 ConstantPool* _prev_constant_pool; // regular or weak reference
1127 bool _prev_cp_is_weak; // true if not a shared ConstantPool
1129 // If the previous version of the InstanceKlass doesn't have any
1130 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1131 // EMCP methods have been collected, then _prev_EMCP_methods can
1132 // have a length of zero.
1133 GrowableArray<Method*>* _prev_EMCP_methods;
1135 public:
1136 PreviousVersionNode(ConstantPool* prev_constant_pool, bool prev_cp_is_weak,
1137 GrowableArray<Method*>* prev_EMCP_methods);
1138 ~PreviousVersionNode();
1139 ConstantPool* prev_constant_pool() const {
1140 return _prev_constant_pool;
1141 }
1142 GrowableArray<Method*>* prev_EMCP_methods() const {
1143 return _prev_EMCP_methods;
1144 }
1145 };
1148 // A Handle-ized version of PreviousVersionNode.
1149 class PreviousVersionInfo : public ResourceObj {
1150 private:
1151 constantPoolHandle _prev_constant_pool_handle;
1152 // If the previous version of the InstanceKlass doesn't have any
1153 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
1154 // methods cannot be collected while we hold a handle,
1155 // _prev_EMCP_methods should never have a length of zero.
1156 GrowableArray<methodHandle>* _prev_EMCP_method_handles;
1158 public:
1159 PreviousVersionInfo(PreviousVersionNode *pv_node);
1160 ~PreviousVersionInfo();
1161 constantPoolHandle prev_constant_pool_handle() const {
1162 return _prev_constant_pool_handle;
1163 }
1164 GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
1165 return _prev_EMCP_method_handles;
1166 }
1167 };
1170 // Helper object for walking previous versions. This helper cleans up
1171 // the Handles that it allocates when the helper object is destroyed.
1172 // The PreviousVersionInfo object returned by next_previous_version()
1173 // is only valid until a subsequent call to next_previous_version() or
1174 // the helper object is destroyed.
1175 class PreviousVersionWalker : public StackObj {
1176 private:
1177 GrowableArray<PreviousVersionNode *>* _previous_versions;
1178 int _current_index;
1179 // Fields for cleaning up when we are done walking the previous versions:
1180 // A HandleMark for the PreviousVersionInfo handles:
1181 HandleMark _hm;
1183 // It would be nice to have a ResourceMark field in this helper also,
1184 // but the ResourceMark code says to be careful to delete handles held
1185 // in GrowableArrays _before_ deleting the GrowableArray. Since we
1186 // can't guarantee the order in which the fields are destroyed, we
1187 // have to let the creator of the PreviousVersionWalker object do
1188 // the right thing. Also, adding a ResourceMark here causes an
1189 // include loop.
1191 // A pointer to the current info object so we can handle the deletes.
1192 PreviousVersionInfo * _current_p;
1194 public:
1195 PreviousVersionWalker(InstanceKlass *ik);
1196 ~PreviousVersionWalker();
1198 // Return the interesting information for the next previous version
1199 // of the klass. Returns NULL if there are no more previous versions.
1200 PreviousVersionInfo* next_previous_version();
1201 };
1204 //
1205 // nmethodBucket is used to record dependent nmethods for
1206 // deoptimization. nmethod dependencies are actually <klass, method>
1207 // pairs but we really only care about the klass part for purposes of
1208 // finding nmethods which might need to be deoptimized. Instead of
1209 // recording the method, a count of how many times a particular nmethod
1210 // was recorded is kept. This ensures that any recording errors are
1211 // noticed since an nmethod should be removed as many times are it's
1212 // added.
1213 //
1214 class nmethodBucket: public CHeapObj<mtClass> {
1215 friend class VMStructs;
1216 private:
1217 nmethod* _nmethod;
1218 int _count;
1219 nmethodBucket* _next;
1221 public:
1222 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1223 _nmethod = nmethod;
1224 _next = next;
1225 _count = 1;
1226 }
1227 int count() { return _count; }
1228 int increment() { _count += 1; return _count; }
1229 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1230 nmethodBucket* next() { return _next; }
1231 void set_next(nmethodBucket* b) { _next = b; }
1232 nmethod* get_nmethod() { return _nmethod; }
1233 };
1235 // An iterator that's used to access the inner classes indices in the
1236 // InstanceKlass::_inner_classes array.
1237 class InnerClassesIterator : public StackObj {
1238 private:
1239 Array<jushort>* _inner_classes;
1240 int _length;
1241 int _idx;
1242 public:
1244 InnerClassesIterator(instanceKlassHandle k) {
1245 _inner_classes = k->inner_classes();
1246 if (k->inner_classes() != NULL) {
1247 _length = _inner_classes->length();
1248 // The inner class array's length should be the multiple of
1249 // inner_class_next_offset if it only contains the InnerClasses
1250 // attribute data, or it should be
1251 // n*inner_class_next_offset+enclosing_method_attribute_size
1252 // if it also contains the EnclosingMethod data.
1253 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1254 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1255 "just checking");
1256 // Remove the enclosing_method portion if exists.
1257 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1258 _length -= InstanceKlass::enclosing_method_attribute_size;
1259 }
1260 } else {
1261 _length = 0;
1262 }
1263 _idx = 0;
1264 }
1266 int length() const {
1267 return _length;
1268 }
1270 void next() {
1271 _idx += InstanceKlass::inner_class_next_offset;
1272 }
1274 bool done() const {
1275 return (_idx >= _length);
1276 }
1278 u2 inner_class_info_index() const {
1279 return _inner_classes->at(
1280 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1281 }
1283 void set_inner_class_info_index(u2 index) {
1284 _inner_classes->at_put(
1285 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1286 }
1288 u2 outer_class_info_index() const {
1289 return _inner_classes->at(
1290 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1291 }
1293 void set_outer_class_info_index(u2 index) {
1294 _inner_classes->at_put(
1295 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1296 }
1298 u2 inner_name_index() const {
1299 return _inner_classes->at(
1300 _idx + InstanceKlass::inner_class_inner_name_offset);
1301 }
1303 void set_inner_name_index(u2 index) {
1304 _inner_classes->at_put(
1305 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1306 }
1308 u2 inner_access_flags() const {
1309 return _inner_classes->at(
1310 _idx + InstanceKlass::inner_class_access_flags_offset);
1311 }
1312 };
1314 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP