1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP
26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
27
28 #include "classfile/classLoaderData.hpp"
29 #include "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"
40
41 // An InstanceKlass is the VM level representation of a Java class.
42 // It contains all information needed for at class at execution runtime.
43
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)
81
82
83 // forward declaration for class -- see below for definition
84 class SuperTypeClosure;
85 class JNIid;
86 class jniIdMapBase;
87 class BreakpointInfo;
88 class fieldDescriptor;
89 class DepChange;
90 class nmethodBucket;
91 class PreviousVersionNode;
92 class JvmtiCachedClassFieldMap;
93 class MemberNameTable;
94
95 // This is used in iterators below.
96 class FieldClosure: public StackObj {
97 public:
98 virtual void do_field(fieldDescriptor* fd) = 0;
99 };
100
101 #ifndef PRODUCT
102 // Print fields.
103 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
104 class FieldPrinter: public FieldClosure {
105 oop _obj;
106 outputStream* _st;
107 public:
108 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
109 void do_field(fieldDescriptor* fd);
110 };
111 #endif // !PRODUCT
112
113 // ValueObjs embedded in klass. Describes where oops are located in instances of
114 // this klass.
115 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
116 public:
117 // Byte offset of the first oop mapped by this block.
118 int offset() const { return _offset; }
119 void set_offset(int offset) { _offset = offset; }
120
121 // Number of oops in this block.
122 uint count() const { return _count; }
123 void set_count(uint count) { _count = count; }
124
125 // sizeof(OopMapBlock) in HeapWords.
126 static const int size_in_words() {
127 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
128 LogHeapWordSize;
129 }
130
131 private:
132 int _offset;
133 uint _count;
134 };
135
136 class InstanceKlass: public Klass {
137 friend class VMStructs;
138 friend class ClassFileParser;
139 friend class CompileReplay;
140
141 protected:
142 // Constructor
143 InstanceKlass(int vtable_len,
144 int itable_len,
145 int static_field_size,
146 int nonstatic_oop_map_size,
147 ReferenceType rt,
148 AccessFlags access_flags,
149 bool is_anonymous);
150 public:
151 static InstanceKlass* allocate_instance_klass(
152 ClassLoaderData* loader_data,
153 int vtable_len,
154 int itable_len,
155 int static_field_size,
156 int nonstatic_oop_map_size,
157 ReferenceType rt,
158 AccessFlags access_flags,
159 Symbol* name,
160 Klass* super_klass,
161 bool is_anonymous,
162 TRAPS);
163
164 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
165
166 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
167 // of the class loading & initialization procedure, and the use of the states.
168 enum ClassState {
169 allocated, // allocated (but not yet linked)
170 loaded, // loaded and inserted in class hierarchy (but not linked yet)
171 linked, // successfully linked/verified (but not initialized yet)
172 being_initialized, // currently running class initializer
173 fully_initialized, // initialized (successfull final state)
174 initialization_error // error happened during initialization
175 };
176
177 static int number_of_instance_classes() { return _total_instanceKlass_count; }
178
179 private:
180 static volatile int _total_instanceKlass_count;
181
182 protected:
183 // Protection domain.
184 oop _protection_domain;
185 // Class signers.
186 objArrayOop _signers;
187 // Initialization lock. Must be one per class and it has to be a VM internal
188 // object so java code cannot lock it (like the mirror)
189 // It has to be an object not a Mutex because it's held through java calls.
190 volatile oop _init_lock;
191
192 // Annotations for this class
193 Annotations* _annotations;
194 // Array classes holding elements of this class.
195 Klass* _array_klasses;
196 // Constant pool for this class.
197 ConstantPool* _constants;
198 // The InnerClasses attribute and EnclosingMethod attribute. The
199 // _inner_classes is an array of shorts. If the class has InnerClasses
200 // attribute, then the _inner_classes array begins with 4-tuples of shorts
201 // [inner_class_info_index, outer_class_info_index,
202 // inner_name_index, inner_class_access_flags] for the InnerClasses
203 // attribute. If the EnclosingMethod attribute exists, it occupies the
204 // last two shorts [class_index, method_index] of the array. If only
205 // the InnerClasses attribute exists, the _inner_classes array length is
206 // number_of_inner_classes * 4. If the class has both InnerClasses
207 // and EnclosingMethod attributes the _inner_classes array length is
208 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
209 Array<jushort>* _inner_classes;
210
211 // Name of source file containing this klass, NULL if not specified.
212 Symbol* _source_file_name;
213 // the source debug extension for this klass, NULL if not specified.
214 // Specified as UTF-8 string without terminating zero byte in the classfile,
215 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
216 char* _source_debug_extension;
217 // Generic signature, or null if none.
218 Symbol* _generic_signature;
219 // Array name derived from this class which needs unreferencing
220 // if this class is unloaded.
221 Symbol* _array_name;
222
223 // Number of heapOopSize words used by non-static fields in this klass
224 // (including inherited fields but after header_size()).
225 int _nonstatic_field_size;
226 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
227 u2 _static_oop_field_count;// number of static oop fields in this klass
228 u2 _java_fields_count; // The number of declared Java fields
229 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
230
231 // _is_marked_dependent can be set concurrently, thus cannot be part of the
232 // _misc_flags.
233 bool _is_marked_dependent; // used for marking during flushing and deoptimization
234
235 enum {
236 _misc_rewritten = 1 << 0, // methods rewritten.
237 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
238 _misc_should_verify_class = 1 << 2, // allow caching of preverification
239 _misc_is_anonymous = 1 << 3, // has embedded _inner_classes field
240 _misc_is_contended = 1 << 4, // marked with contended annotation
241 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods
242 };
243 u2 _misc_flags;
244 u2 _minor_version; // minor version number of class file
245 u2 _major_version; // major version number of class file
246 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
247 int _vtable_len; // length of Java vtable (in words)
248 int _itable_len; // length of Java itable (in words)
249 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
250 MemberNameTable* _member_names; // Member names
251 JNIid* _jni_ids; // First JNI identifier for static fields in this class
252 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
253 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
254 nmethodBucket* _dependencies; // list of dependent nmethods
255 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
256 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
257 // Array of interesting part(s) of the previous version(s) of this
258 // InstanceKlass. See PreviousVersionWalker below.
259 GrowableArray<PreviousVersionNode *>* _previous_versions;
260 // JVMTI fields can be moved to their own structure - see 6315920
261 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH
262 jint _cached_class_file_len; // JVMTI: length of above
263
264 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
265
266 // Class states are defined as ClassState (see above).
267 // Place the _init_state here to utilize the unused 2-byte after
268 // _idnum_allocated_count.
269 u1 _init_state; // state of class
270 u1 _reference_type; // reference type
271
272 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
273
274 NOT_PRODUCT(int _verify_count;) // to avoid redundant verifies
275
276 // Method array.
277 Array<Method*>* _methods;
278 // Interface (Klass*s) this class declares locally to implement.
279 Array<Klass*>* _local_interfaces;
280 // Interface (Klass*s) this class implements transitively.
281 Array<Klass*>* _transitive_interfaces;
282 // Int array containing the original order of method in the class file (for JVMTI).
283 Array<int>* _method_ordering;
284 // Instance and static variable information, starts with 6-tuples of shorts
285 // [access, name index, sig index, initval index, low_offset, high_offset]
286 // for all fields, followed by the generic signature data at the end of
287 // the array. Only fields with generic signature attributes have the generic
288 // signature data set in the array. The fields array looks like following:
289 //
290 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
291 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
292 // ...
293 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
294 // [generic signature index]
295 // [generic signature index]
296 // ...
297 Array<u2>* _fields;
298
299 // embedded Java vtable follows here
300 // embedded Java itables follows here
301 // embedded static fields follows here
302 // embedded nonstatic oop-map blocks follows here
303 // embedded implementor of this interface follows here
304 // The embedded implementor only exists if the current klass is an
305 // iterface. The possible values of the implementor fall into following
306 // three cases:
307 // NULL: no implementor.
308 // A Klass* that's not itself: one implementor.
309 // Itsef: more than one implementors.
310 // embedded host klass follows here
311 // The embedded host klass only exists in an anonymous class for
312 // dynamic language support (JSR 292 enabled). The host class grants
313 // its access privileges to this class also. The host class is either
314 // named, or a previously loaded anonymous class. A non-anonymous class
315 // or an anonymous class loaded through normal classloading does not
316 // have this embedded field.
317 //
318
319 friend class SystemDictionary;
320
321 public:
322 bool has_nonstatic_fields() const {
323 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
324 }
325 void set_has_nonstatic_fields(bool b) {
326 if (b) {
327 _misc_flags |= _misc_has_nonstatic_fields;
328 } else {
329 _misc_flags &= ~_misc_has_nonstatic_fields;
330 }
331 }
332
333 // field sizes
334 int nonstatic_field_size() const { return _nonstatic_field_size; }
335 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
336
337 int static_field_size() const { return _static_field_size; }
338 void set_static_field_size(int size) { _static_field_size = size; }
339
340 int static_oop_field_count() const { return (int)_static_oop_field_count; }
341 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
342
343 // Java vtable
344 int vtable_length() const { return _vtable_len; }
345 void set_vtable_length(int len) { _vtable_len = len; }
346
347 // Java itable
348 int itable_length() const { return _itable_len; }
349 void set_itable_length(int len) { _itable_len = len; }
350
351 // array klasses
352 Klass* array_klasses() const { return _array_klasses; }
353 void set_array_klasses(Klass* k) { _array_klasses = k; }
354
355 // methods
356 Array<Method*>* methods() const { return _methods; }
357 void set_methods(Array<Method*>* a) { _methods = a; }
358 Method* method_with_idnum(int idnum);
359
360 // method ordering
361 Array<int>* method_ordering() const { return _method_ordering; }
362 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
363 void copy_method_ordering(intArray* m, TRAPS);
364
365 // interfaces
366 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
367 void set_local_interfaces(Array<Klass*>* a) {
368 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
369 _local_interfaces = a; }
370
371 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
372 void set_transitive_interfaces(Array<Klass*>* a) {
373 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
374 _transitive_interfaces = a;
375 }
376
377 private:
378 friend class fieldDescriptor;
379 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
380
381 public:
382 int field_offset (int index) const { return field(index)->offset(); }
383 int field_access_flags(int index) const { return field(index)->access_flags(); }
384 Symbol* field_name (int index) const { return field(index)->name(constants()); }
385 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
386
387 // Number of Java declared fields
388 int java_fields_count() const { return (int)_java_fields_count; }
389
390 Array<u2>* fields() const { return _fields; }
391 void set_fields(Array<u2>* f, u2 java_fields_count) {
392 guarantee(_fields == NULL || f == NULL, "Just checking");
393 _fields = f;
394 _java_fields_count = java_fields_count;
395 }
396
397 // inner classes
398 Array<u2>* inner_classes() const { return _inner_classes; }
399 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
400
401 enum InnerClassAttributeOffset {
402 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
403 inner_class_inner_class_info_offset = 0,
404 inner_class_outer_class_info_offset = 1,
405 inner_class_inner_name_offset = 2,
406 inner_class_access_flags_offset = 3,
407 inner_class_next_offset = 4
408 };
409
410 enum EnclosingMethodAttributeOffset {
411 enclosing_method_class_index_offset = 0,
412 enclosing_method_method_index_offset = 1,
413 enclosing_method_attribute_size = 2
414 };
415
416 // method override check
417 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
418
419 // package
420 bool is_same_class_package(Klass* class2);
421 bool is_same_class_package(oop classloader2, Symbol* classname2);
422 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
423
424 // find an enclosing class (defined where original code was, in jvm.cpp!)
425 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
426 instanceKlassHandle self(THREAD, this);
427 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
428 }
429 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
430 bool* inner_is_member, TRAPS);
431
432 // tell if two classes have the same enclosing class (at package level)
433 bool is_same_package_member(Klass* class2, TRAPS) {
434 instanceKlassHandle self(THREAD, this);
435 return is_same_package_member_impl(self, class2, THREAD);
436 }
437 static bool is_same_package_member_impl(instanceKlassHandle self,
438 Klass* class2, TRAPS);
439
440 // initialization state
441 bool is_loaded() const { return _init_state >= loaded; }
442 bool is_linked() const { return _init_state >= linked; }
443 bool is_initialized() const { return _init_state == fully_initialized; }
444 bool is_not_initialized() const { return _init_state < being_initialized; }
445 bool is_being_initialized() const { return _init_state == being_initialized; }
446 bool is_in_error_state() const { return _init_state == initialization_error; }
447 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
448 ClassState init_state() { return (ClassState)_init_state; }
449 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
450
451 // defineClass specified verification
452 bool should_verify_class() const {
453 return (_misc_flags & _misc_should_verify_class) != 0;
454 }
455 void set_should_verify_class(bool value) {
456 if (value) {
457 _misc_flags |= _misc_should_verify_class;
458 } else {
459 _misc_flags &= ~_misc_should_verify_class;
460 }
461 }
462
463 // marking
464 bool is_marked_dependent() const { return _is_marked_dependent; }
465 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
466
467 // initialization (virtuals from Klass)
468 bool should_be_initialized() const; // means that initialize should be called
469 void initialize(TRAPS);
470 void link_class(TRAPS);
471 bool link_class_or_fail(TRAPS); // returns false on failure
472 void unlink_class();
473 void rewrite_class(TRAPS);
474 void link_methods(TRAPS);
475 Method* class_initializer();
476
477 // set the class to initialized if no static initializer is present
478 void eager_initialize(Thread *thread);
479
480 // reference type
481 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
482 void set_reference_type(ReferenceType t) {
483 assert(t == (u1)t, "overflow");
484 _reference_type = (u1)t;
485 }
486
487 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
488
489 // find local field, returns true if found
490 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
491 // find field in direct superinterfaces, returns the interface in which the field is defined
492 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
493 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
494 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
495 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
496 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
497
498 // find a non-static or static field given its offset within the class.
499 bool contains_field_offset(int offset) {
500 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
501 }
502
503 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
504 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
505
506 // find a local method (returns NULL if not found)
507 Method* find_method(Symbol* name, Symbol* signature) const;
508 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
509
510 // lookup operation (returns NULL if not found)
511 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const;
512
513 // lookup a method in all the interfaces that this class implements
514 // (returns NULL if not found)
515 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature) const;
516
517 // Find method indices by name. If a method with the specified name is
518 // found the index to the first method is returned, and 'end' is filled in
519 // with the index of first non-name-matching method. If no method is found
520 // -1 is returned.
521 int find_method_by_name(Symbol* name, int* end);
522 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
523
524 // constant pool
525 ConstantPool* constants() const { return _constants; }
526 void set_constants(ConstantPool* c) { _constants = c; }
527
528 // protection domain
529 oop protection_domain() { return _protection_domain; }
530 void set_protection_domain(oop pd) { klass_oop_store(&_protection_domain, pd); }
531
532 // host class
533 Klass* host_klass() const {
534 Klass** hk = (Klass**)adr_host_klass();
535 if (hk == NULL) {
536 return NULL;
537 } else {
538 return *hk;
539 }
540 }
541 void set_host_klass(Klass* host) {
542 assert(is_anonymous(), "not anonymous");
543 Klass** addr = (Klass**)adr_host_klass();
544 assert(addr != NULL, "no reversed space");
545 if (addr != NULL) {
546 *addr = host;
547 }
548 }
549 bool is_anonymous() const {
550 return (_misc_flags & _misc_is_anonymous) != 0;
551 }
552 void set_is_anonymous(bool value) {
553 if (value) {
554 _misc_flags |= _misc_is_anonymous;
555 } else {
556 _misc_flags &= ~_misc_is_anonymous;
557 }
558 }
559
560 // Oop that keeps the metadata for this class from being unloaded
561 // in places where the metadata is stored in other places, like nmethods
562 oop klass_holder() const {
563 return is_anonymous() ? java_mirror() : class_loader();
564 }
565
566 bool is_contended() const {
567 return (_misc_flags & _misc_is_contended) != 0;
568 }
569 void set_is_contended(bool value) {
570 if (value) {
571 _misc_flags |= _misc_is_contended;
572 } else {
573 _misc_flags &= ~_misc_is_contended;
574 }
575 }
576
577 // signers
578 objArrayOop signers() const { return _signers; }
579 void set_signers(objArrayOop s) { klass_oop_store((oop*)&_signers, s); }
580
581 // source file name
582 Symbol* source_file_name() const { return _source_file_name; }
583 void set_source_file_name(Symbol* n);
584
585 // minor and major version numbers of class file
586 u2 minor_version() const { return _minor_version; }
587 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
588 u2 major_version() const { return _major_version; }
589 void set_major_version(u2 major_version) { _major_version = major_version; }
590
591 // source debug extension
592 char* source_debug_extension() const { return _source_debug_extension; }
593 void set_source_debug_extension(char* array, int length);
594
595 // symbol unloading support (refcount already added)
596 Symbol* array_name() { return _array_name; }
597 void set_array_name(Symbol* name) { assert(_array_name == NULL || name == NULL, "name already created"); _array_name = name; }
598
599 // nonstatic oop-map blocks
600 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
601 return oop_map_count * OopMapBlock::size_in_words();
602 }
603 unsigned int nonstatic_oop_map_count() const {
604 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
605 }
606 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
607 void set_nonstatic_oop_map_size(int words) {
608 _nonstatic_oop_map_size = words;
609 }
610
611 // RedefineClasses() support for previous versions:
612 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
613 int emcp_method_count);
614 // If the _previous_versions array is non-NULL, then this klass
615 // has been redefined at least once even if we aren't currently
616 // tracking a previous version.
617 bool has_been_redefined() const { return _previous_versions != NULL; }
618 bool has_previous_version() const;
619 void init_previous_versions() {
620 _previous_versions = NULL;
621 }
622 GrowableArray<PreviousVersionNode *>* previous_versions() const {
623 return _previous_versions;
624 }
625
626 static void purge_previous_versions(InstanceKlass* ik);
627
628 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
629 void set_cached_class_file(unsigned char *class_file_bytes,
630 jint class_file_len) { _cached_class_file_len = class_file_len;
631 _cached_class_file_bytes = class_file_bytes; }
632 jint get_cached_class_file_len() { return _cached_class_file_len; }
633 unsigned char * get_cached_class_file_bytes() { return _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 { return _generic_signature; }
660 void set_generic_signature(Symbol* sig) { _generic_signature = sig; }
661
662 u2 enclosing_method_data(int offset);
663 u2 enclosing_method_class_index() {
664 return enclosing_method_data(enclosing_method_class_index_offset);
665 }
666 u2 enclosing_method_method_index() {
667 return enclosing_method_data(enclosing_method_method_index_offset);
668 }
669 void set_enclosing_method_indices(u2 class_index,
670 u2 method_index);
671
672 // jmethodID support
673 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
674 methodHandle method_h);
675 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
676 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
677 jmethodID* to_dealloc_id_p,
678 jmethodID** to_dealloc_jmeths_p);
679 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
680 size_t *length_p, jmethodID* id_p);
681 jmethodID jmethod_id_or_null(Method* method);
682
683 // cached itable index support
684 void set_cached_itable_index(size_t idnum, int index);
685 int cached_itable_index(size_t idnum);
686
687 // annotations support
688 Annotations* annotations() const { return _annotations; }
689 void set_annotations(Annotations* anno) { _annotations = anno; }
690
691 AnnotationArray* class_annotations() const {
692 return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
693 }
694 Array<AnnotationArray*>* fields_annotations() const {
695 return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
696 }
697 AnnotationArray* class_type_annotations() const {
698 return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
699 }
700 Array<AnnotationArray*>* fields_type_annotations() const {
701 return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
702 }
703 // allocation
704 instanceOop allocate_instance(TRAPS);
705
706 // additional member function to return a handle
707 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
708
709 objArrayOop allocate_objArray(int n, int length, TRAPS);
710 // Helper function
711 static instanceOop register_finalizer(instanceOop i, TRAPS);
712
713 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
714 // if not, throw either an Error or an Exception.
715 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
716
717 // initialization
718 void call_class_initializer(TRAPS);
719 void set_initialization_state_and_notify(ClassState state, TRAPS);
720
721 // OopMapCache support
722 OopMapCache* oop_map_cache() { return _oop_map_cache; }
723 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
724 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
725
726 // JNI identifier support (for static fields - for jni performance)
727 JNIid* jni_ids() { return _jni_ids; }
728 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
729 JNIid* jni_id_for(int offset);
730
731 // maintenance of deoptimization dependencies
732 int mark_dependent_nmethods(DepChange& changes);
733 void add_dependent_nmethod(nmethod* nm);
734 void remove_dependent_nmethod(nmethod* nm);
735
736 // On-stack replacement support
737 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
738 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
739 void add_osr_nmethod(nmethod* n);
740 void remove_osr_nmethod(nmethod* n);
741 nmethod* lookup_osr_nmethod(Method* const m, int bci, int level, bool match_level) const;
742
743 // Breakpoint support (see methods on Method* for details)
744 BreakpointInfo* breakpoints() const { return _breakpoints; };
745 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
746
747 // support for stub routines
748 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
749 TRACE_DEFINE_OFFSET;
750 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
751
752 // subclass/subinterface checks
753 bool implements_interface(Klass* k) const;
754
755 // Access to the implementor of an interface.
756 Klass* implementor() const
757 {
758 Klass** k = adr_implementor();
759 if (k == NULL) {
760 return NULL;
761 } else {
762 return *k;
763 }
764 }
765
766 void set_implementor(Klass* k) {
767 assert(is_interface(), "not interface");
768 Klass** addr = adr_implementor();
769 assert(addr != NULL, "null addr");
770 if (addr != NULL) {
771 *addr = k;
772 }
773 }
774
775 int nof_implementors() const {
776 Klass* k = implementor();
777 if (k == NULL) {
778 return 0;
779 } else if (k != this) {
780 return 1;
781 } else {
782 return 2;
783 }
784 }
785
786 void add_implementor(Klass* k); // k is a new class that implements this interface
787 void init_implementor(); // initialize
788
789 // link this class into the implementors list of every interface it implements
790 void process_interfaces(Thread *thread);
791
792 // virtual operations from Klass
793 bool is_leaf_class() const { return _subklass == NULL; }
794 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
795 bool compute_is_subtype_of(Klass* k);
796 bool can_be_primary_super_slow() const;
797 int oop_size(oop obj) const { return size_helper(); }
798 bool oop_is_instance_slow() const { return true; }
799
800 // Iterators
801 void do_local_static_fields(FieldClosure* cl);
802 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
803 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
804
805 void methods_do(void f(Method* method));
806 void array_klasses_do(void f(Klass* k));
807 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
808 void with_array_klasses_do(void f(Klass* k));
809 bool super_types_do(SuperTypeClosure* blk);
810
811 // Casting from Klass*
812 static InstanceKlass* cast(Klass* k) {
813 assert(k->is_klass(), "must be");
814 assert(k->oop_is_instance(), "cast to InstanceKlass");
815 return (InstanceKlass*) k;
816 }
817
818 InstanceKlass* java_super() const {
819 return (super() == NULL) ? NULL : cast(super());
820 }
821
822 // Sizing (in words)
823 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
824
825 static int size(int vtable_length, int itable_length,
826 int nonstatic_oop_map_size,
827 bool is_interface, bool is_anonymous) {
828 return align_object_size(header_size() +
829 align_object_offset(vtable_length) +
830 align_object_offset(itable_length) +
831 ((is_interface || is_anonymous) ?
832 align_object_offset(nonstatic_oop_map_size) :
833 nonstatic_oop_map_size) +
834 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
835 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
836 }
837 int size() const { return size(vtable_length(),
838 itable_length(),
839 nonstatic_oop_map_size(),
840 is_interface(),
841 is_anonymous());
842 }
843 #if INCLUDE_SERVICES
844 virtual void collect_statistics(KlassSizeStats *sz) const;
845 #endif
846
847 static int vtable_start_offset() { return header_size(); }
848 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
849
850 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
851 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
852 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
853
854 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
855
856 address static_field_addr(int offset);
857
858 OopMapBlock* start_of_nonstatic_oop_maps() const {
859 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
860 }
861
862 Klass** end_of_nonstatic_oop_maps() const {
863 return (Klass**)(start_of_nonstatic_oop_maps() +
864 nonstatic_oop_map_count());
865 }
866
867 Klass** adr_implementor() const {
868 if (is_interface()) {
869 return (Klass**)end_of_nonstatic_oop_maps();
870 } else {
871 return NULL;
872 }
873 };
874
875 Klass** adr_host_klass() const {
876 if (is_anonymous()) {
877 Klass** adr_impl = adr_implementor();
878 if (adr_impl != NULL) {
879 return adr_impl + 1;
880 } else {
881 return end_of_nonstatic_oop_maps();
882 }
883 } else {
884 return NULL;
885 }
886 }
887
888 // Allocation profiling support
889 juint alloc_size() const { return _alloc_count * size_helper(); }
890 void set_alloc_size(juint n) {}
891
892 // Use this to return the size of an instance in heap words:
893 int size_helper() const {
894 return layout_helper_to_size_helper(layout_helper());
895 }
896
897 // This bit is initialized in classFileParser.cpp.
898 // It is false under any of the following conditions:
899 // - the class is abstract (including any interface)
900 // - the class has a finalizer (if !RegisterFinalizersAtInit)
901 // - the class size is larger than FastAllocateSizeLimit
902 // - the class is java/lang/Class, which cannot be allocated directly
903 bool can_be_fastpath_allocated() const {
904 return !layout_helper_needs_slow_path(layout_helper());
905 }
906
907 // Java vtable/itable
908 klassVtable* vtable() const; // return new klassVtable wrapper
909 inline Method* method_at_vtable(int index);
910 klassItable* itable() const; // return new klassItable wrapper
911 Method* method_at_itable(Klass* holder, int index, TRAPS);
912
913 // Garbage collection
914 virtual void oops_do(OopClosure* cl);
915
916 void oop_follow_contents(oop obj);
917 int oop_adjust_pointers(oop obj);
918
919 void clean_implementors_list(BoolObjectClosure* is_alive);
920 void clean_method_data(BoolObjectClosure* is_alive);
921
922 // Explicit metaspace deallocation of fields
923 // For RedefineClasses and class file parsing errors, we need to deallocate
924 // instanceKlasses and the metadata they point to.
925 void deallocate_contents(ClassLoaderData* loader_data);
926 static void deallocate_methods(ClassLoaderData* loader_data,
927 Array<Method*>* methods);
928 void static deallocate_interfaces(ClassLoaderData* loader_data,
929 Klass* super_klass,
930 Array<Klass*>* local_interfaces,
931 Array<Klass*>* transitive_interfaces);
932
933 // The constant pool is on stack if any of the methods are executing or
934 // referenced by handles.
935 bool on_stack() const { return _constants->on_stack(); }
936
937 void release_C_heap_structures();
938
939 // Parallel Scavenge and Parallel Old
940 PARALLEL_GC_DECLS
941
942 // Naming
943 const char* signature_name() const;
944
945 // Iterators
946 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
947 return oop_oop_iterate_v(obj, blk);
948 }
949
950 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
951 return oop_oop_iterate_v_m(obj, blk, mr);
952 }
953
954 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
955 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
956 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
957 MemRegion mr);
958
959 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
960 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
961
962 #if INCLUDE_ALL_GCS
963 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
964 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
965
966 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
967 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
968 #endif // INCLUDE_ALL_GCS
969
970 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
971 private:
972 // initialization state
973 #ifdef ASSERT
974 void set_init_state(ClassState state);
975 #else
976 void set_init_state(ClassState state) { _init_state = (u1)state; }
977 #endif
978 void set_rewritten() { _misc_flags |= _misc_rewritten; }
979 void set_init_thread(Thread *thread) { _init_thread = thread; }
980
981 // The RedefineClasses() API can cause new method idnums to be needed
982 // which will cause the caches to grow. Safety requires different
983 // cache management logic if the caches can grow instead of just
984 // going from NULL to non-NULL.
985 bool idnum_can_increment() const { return has_been_redefined(); }
986 jmethodID* methods_jmethod_ids_acquire() const
987 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
988 void release_set_methods_jmethod_ids(jmethodID* jmeths)
989 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
990
991 int* methods_cached_itable_indices_acquire() const
992 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
993 void release_set_methods_cached_itable_indices(int* indices)
994 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
995
996 // Lock during initialization
997 volatile oop init_lock() const;
998 void set_init_lock(oop value) { klass_oop_store(&_init_lock, value); }
999 void fence_and_clear_init_lock(); // after fully_initialized
1000
1001 // Offsets for memory management
1002 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
1003 oop* adr_signers() const { return (oop*)&this->_signers;}
1004 oop* adr_init_lock() const { return (oop*)&this->_init_lock;}
1005
1006 // Static methods that are used to implement member methods where an exposed this pointer
1007 // is needed due to possible GCs
1008 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1009 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1010 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
1011 static void eager_initialize_impl (instanceKlassHandle this_oop);
1012 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
1013 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
1014 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
1015 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
1016 /* jni_id_for_impl for jfieldID only */
1017 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
1018
1019 // Returns the array class for the n'th dimension
1020 Klass* array_klass_impl(bool or_null, int n, TRAPS);
1021
1022 // Returns the array class with this class as element type
1023 Klass* array_klass_impl(bool or_null, TRAPS);
1024
1025 public:
1026 // CDS support - remove and restore oops from metadata. Oops are not shared.
1027 virtual void remove_unshareable_info();
1028 virtual void restore_unshareable_info(TRAPS);
1029
1030 // jvm support
1031 jint compute_modifier_flags(TRAPS) const;
1032
1033 // JSR-292 support
1034 MemberNameTable* member_names() { return _member_names; }
1035 void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1036 void add_member_name(Handle member_name);
1037
1038 public:
1039 // JVMTI support
1040 jint jvmti_class_status() const;
1041
1042 public:
1043 // Printing
1044 #ifndef PRODUCT
1045 void print_on(outputStream* st) const;
1046 #endif
1047 void print_value_on(outputStream* st) const;
1048
1049 void oop_print_value_on(oop obj, outputStream* st);
1050
1051 #ifndef PRODUCT
1052 void oop_print_on (oop obj, outputStream* st);
1053
1054 void print_dependent_nmethods(bool verbose = false);
1055 bool is_dependent_nmethod(nmethod* nm);
1056 #endif
1057
1058 const char* internal_name() const;
1059
1060 // Verification
1061 void verify_on(outputStream* st);
1062
1063 void oop_verify_on(oop obj, outputStream* st);
1064 };
1065
1066 inline Method* InstanceKlass::method_at_vtable(int index) {
1067 #ifndef PRODUCT
1068 assert(index >= 0, "valid vtable index");
1069 if (DebugVtables) {
1070 verify_vtable_index(index);
1071 }
1072 #endif
1073 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1074 return ve[index].method();
1075 }
1076
1077 // for adding methods
1078 // UNSET_IDNUM return means no more ids available
1079 inline u2 InstanceKlass::next_method_idnum() {
1080 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1081 return ConstMethod::UNSET_IDNUM; // no more ids available
1082 } else {
1083 return _idnum_allocated_count++;
1084 }
1085 }
1086
1087
1088 /* JNIid class for jfieldIDs only */
1089 class JNIid: public CHeapObj<mtClass> {
1090 friend class VMStructs;
1091 private:
1092 Klass* _holder;
1093 JNIid* _next;
1094 int _offset;
1095 #ifdef ASSERT
1096 bool _is_static_field_id;
1097 #endif
1098
1099 public:
1100 // Accessors
1101 Klass* holder() const { return _holder; }
1102 int offset() const { return _offset; }
1103 JNIid* next() { return _next; }
1104 // Constructor
1105 JNIid(Klass* holder, int offset, JNIid* next);
1106 // Identifier lookup
1107 JNIid* find(int offset);
1108
1109 bool find_local_field(fieldDescriptor* fd) {
1110 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1111 }
1112
1113 static void deallocate(JNIid* id);
1114 // Debugging
1115 #ifdef ASSERT
1116 bool is_static_field_id() const { return _is_static_field_id; }
1117 void set_is_static_field_id() { _is_static_field_id = true; }
1118 #endif
1119 void verify(Klass* holder);
1120 };
1121
1122
1123 // If breakpoints are more numerous than just JVMTI breakpoints,
1124 // consider compressing this data structure.
1125 // It is currently a simple linked list defined in method.hpp.
1126
1127 class BreakpointInfo;
1128
1129
1130 // A collection point for interesting information about the previous
1131 // version(s) of an InstanceKlass. This class uses weak references to
1132 // the information so that the information may be collected as needed
1133 // by the system. If the information is shared, then a regular
1134 // reference must be used because a weak reference would be seen as
1135 // collectible. A GrowableArray of PreviousVersionNodes is attached
1136 // to the InstanceKlass as needed. See PreviousVersionWalker below.
1137 class PreviousVersionNode : public CHeapObj<mtClass> {
1138 private:
1139 // A shared ConstantPool is never collected so we'll always have
1140 // a reference to it so we can update items in the cache. We'll
1141 // have a weak reference to a non-shared ConstantPool until all
1142 // of the methods (EMCP or obsolete) have been collected; the
1143 // non-shared ConstantPool becomes collectible at that point.
1144 ConstantPool* _prev_constant_pool; // regular or weak reference
1145 bool _prev_cp_is_weak; // true if not a shared ConstantPool
1146
1147 // If the previous version of the InstanceKlass doesn't have any
1148 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1149 // EMCP methods have been collected, then _prev_EMCP_methods can
1150 // have a length of zero.
1151 GrowableArray<Method*>* _prev_EMCP_methods;
1152
1153 public:
1154 PreviousVersionNode(ConstantPool* prev_constant_pool, bool prev_cp_is_weak,
1155 GrowableArray<Method*>* prev_EMCP_methods);
1156 ~PreviousVersionNode();
1157 ConstantPool* prev_constant_pool() const {
1158 return _prev_constant_pool;
1159 }
1160 GrowableArray<Method*>* prev_EMCP_methods() const {
1161 return _prev_EMCP_methods;
1162 }
1163 };
1164
1165
1166 // A Handle-ized version of PreviousVersionNode.
1167 class PreviousVersionInfo : public ResourceObj {
1168 private:
1169 constantPoolHandle _prev_constant_pool_handle;
1170 // If the previous version of the InstanceKlass doesn't have any
1171 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
1172 // methods cannot be collected while we hold a handle,
1173 // _prev_EMCP_methods should never have a length of zero.
1174 GrowableArray<methodHandle>* _prev_EMCP_method_handles;
1175
1176 public:
1177 PreviousVersionInfo(PreviousVersionNode *pv_node);
1178 ~PreviousVersionInfo();
1179 constantPoolHandle prev_constant_pool_handle() const {
1180 return _prev_constant_pool_handle;
1181 }
1182 GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
1183 return _prev_EMCP_method_handles;
1184 }
1185 };
1186
1187
1188 // Helper object for walking previous versions. This helper cleans up
1189 // the Handles that it allocates when the helper object is destroyed.
1190 // The PreviousVersionInfo object returned by next_previous_version()
1191 // is only valid until a subsequent call to next_previous_version() or
1192 // the helper object is destroyed.
1193 class PreviousVersionWalker : public StackObj {
1194 private:
1195 GrowableArray<PreviousVersionNode *>* _previous_versions;
1196 int _current_index;
1197 // Fields for cleaning up when we are done walking the previous versions:
1198 // A HandleMark for the PreviousVersionInfo handles:
1199 HandleMark _hm;
1200
1201 // It would be nice to have a ResourceMark field in this helper also,
1202 // but the ResourceMark code says to be careful to delete handles held
1203 // in GrowableArrays _before_ deleting the GrowableArray. Since we
1204 // can't guarantee the order in which the fields are destroyed, we
1205 // have to let the creator of the PreviousVersionWalker object do
1206 // the right thing. Also, adding a ResourceMark here causes an
1207 // include loop.
1208
1209 // A pointer to the current info object so we can handle the deletes.
1210 PreviousVersionInfo * _current_p;
1211
1212 public:
1213 PreviousVersionWalker(InstanceKlass *ik);
1214 ~PreviousVersionWalker();
1215
1216 // Return the interesting information for the next previous version
1217 // of the klass. Returns NULL if there are no more previous versions.
1218 PreviousVersionInfo* next_previous_version();
1219 };
1220
1221
1222 //
1223 // nmethodBucket is used to record dependent nmethods for
1224 // deoptimization. nmethod dependencies are actually <klass, method>
1225 // pairs but we really only care about the klass part for purposes of
1226 // finding nmethods which might need to be deoptimized. Instead of
1227 // recording the method, a count of how many times a particular nmethod
1228 // was recorded is kept. This ensures that any recording errors are
1229 // noticed since an nmethod should be removed as many times are it's
1230 // added.
1231 //
1232 class nmethodBucket: public CHeapObj<mtClass> {
1233 friend class VMStructs;
1234 private:
1235 nmethod* _nmethod;
1236 int _count;
1237 nmethodBucket* _next;
1238
1239 public:
1240 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1241 _nmethod = nmethod;
1242 _next = next;
1243 _count = 1;
1244 }
1245 int count() { return _count; }
1246 int increment() { _count += 1; return _count; }
1247 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1248 nmethodBucket* next() { return _next; }
1249 void set_next(nmethodBucket* b) { _next = b; }
1250 nmethod* get_nmethod() { return _nmethod; }
1251 };
1252
1253 // An iterator that's used to access the inner classes indices in the
1254 // InstanceKlass::_inner_classes array.
1255 class InnerClassesIterator : public StackObj {
1256 private:
1257 Array<jushort>* _inner_classes;
1258 int _length;
1259 int _idx;
1260 public:
1261
1262 InnerClassesIterator(instanceKlassHandle k) {
1263 _inner_classes = k->inner_classes();
1264 if (k->inner_classes() != NULL) {
1265 _length = _inner_classes->length();
1266 // The inner class array's length should be the multiple of
1267 // inner_class_next_offset if it only contains the InnerClasses
1268 // attribute data, or it should be
1269 // n*inner_class_next_offset+enclosing_method_attribute_size
1270 // if it also contains the EnclosingMethod data.
1271 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1272 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1273 "just checking");
1274 // Remove the enclosing_method portion if exists.
1275 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1276 _length -= InstanceKlass::enclosing_method_attribute_size;
1277 }
1278 } else {
1279 _length = 0;
1280 }
1281 _idx = 0;
1282 }
1283
1284 int length() const {
1285 return _length;
1286 }
1287
1288 void next() {
1289 _idx += InstanceKlass::inner_class_next_offset;
1290 }
1291
1292 bool done() const {
1293 return (_idx >= _length);
1294 }
1295
1296 u2 inner_class_info_index() const {
1297 return _inner_classes->at(
1298 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1299 }
1300
1301 void set_inner_class_info_index(u2 index) {
1302 _inner_classes->at_put(
1303 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1304 }
1305
1306 u2 outer_class_info_index() const {
1307 return _inner_classes->at(
1308 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1309 }
1310
1311 void set_outer_class_info_index(u2 index) {
1312 _inner_classes->at_put(
1313 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1314 }
1315
1316 u2 inner_name_index() const {
1317 return _inner_classes->at(
1318 _idx + InstanceKlass::inner_class_inner_name_offset);
1319 }
1320
1321 void set_inner_name_index(u2 index) {
1322 _inner_classes->at_put(
1323 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1324 }
1325
1326 u2 inner_access_flags() const {
1327 return _inner_classes->at(
1328 _idx + InstanceKlass::inner_class_access_flags_offset);
1329 }
1330 };
1331
1332 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP