1 /*
2 * Copyright (c) 1997, 2012, 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
40 // An InstanceKlass is the VM level representation of a Java class.
41 // It contains all information needed for at class at execution runtime.
42
43 // InstanceKlass layout:
44 // [C++ vtbl pointer ] Klass
45 // [subtype cache ] Klass
46 // [instance size ] Klass
47 // [java mirror ] Klass
48 // [super ] Klass
49 // [access_flags ] Klass
50 // [name ] Klass
51 // [first subklass ] Klass
52 // [next sibling ] Klass
53 // [array klasses ]
54 // [methods ]
55 // [local interfaces ]
56 // [transitive interfaces ]
57 // [fields ]
58 // [constants ]
59 // [class loader ]
60 // [protection domain ]
61 // [signers ]
62 // [source file name ]
63 // [inner classes ]
64 // [static field size ]
65 // [nonstatic field size ]
66 // [static oop fields size ]
67 // [nonstatic oop maps size ]
68 // [has finalize method ]
69 // [deoptimization mark bit ]
70 // [initialization state ]
71 // [initializing thread ]
72 // [Java vtable length ]
73 // [oop map cache (stack maps) ]
74 // [EMBEDDED Java vtable ] size in words = vtable_len
75 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
76 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
77 // indicating where oops are located in instances of this klass.
78 // [EMBEDDED implementor of the interface] only exist for interface
79 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled)
80
81
82 // forward declaration for class -- see below for definition
83 class SuperTypeClosure;
84 class JNIid;
85 class jniIdMapBase;
86 class BreakpointInfo;
87 class fieldDescriptor;
88 class DepChange;
89 class nmethodBucket;
90 class PreviousVersionNode;
91 class JvmtiCachedClassFieldMap;
92
93 // This is used in iterators below.
94 class FieldClosure: public StackObj {
95 public:
96 virtual void do_field(fieldDescriptor* fd) = 0;
97 };
98
99 #ifndef PRODUCT
100 // Print fields.
101 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
102 class FieldPrinter: public FieldClosure {
103 oop _obj;
104 outputStream* _st;
105 public:
106 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
107 void do_field(fieldDescriptor* fd);
108 };
109 #endif // !PRODUCT
110
111 // ValueObjs embedded in klass. Describes where oops are located in instances of
112 // this klass.
113 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
114 public:
115 // Byte offset of the first oop mapped by this block.
116 int offset() const { return _offset; }
117 void set_offset(int offset) { _offset = offset; }
118
119 // Number of oops in this block.
120 uint count() const { return _count; }
121 void set_count(uint count) { _count = count; }
122
123 // sizeof(OopMapBlock) in HeapWords.
124 static const int size_in_words() {
125 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
126 LogHeapWordSize;
127 }
128
129 private:
130 int _offset;
131 uint _count;
132 };
133
134 class InstanceKlass: public Klass {
135 friend class VMStructs;
136 friend class ClassFileParser;
137 friend class CompileReplay;
138
139 protected:
140 // Constructor
141 InstanceKlass(int vtable_len,
142 int itable_len,
143 int static_field_size,
144 int nonstatic_oop_map_size,
145 ReferenceType rt,
146 AccessFlags access_flags,
147 bool is_anonymous);
148 public:
149 static Klass* allocate_instance_klass(ClassLoaderData* loader_data,
150 int vtable_len,
151 int itable_len,
152 int static_field_size,
153 int nonstatic_oop_map_size,
154 ReferenceType rt,
155 AccessFlags access_flags,
156 Symbol* name,
157 Klass* super_klass,
158 KlassHandle host_klass,
159 TRAPS);
160
161 InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
162
163 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
164 // of the class loading & initialization procedure, and the use of the states.
165 enum ClassState {
166 allocated, // allocated (but not yet linked)
167 loaded, // loaded and inserted in class hierarchy (but not linked yet)
168 linked, // successfully linked/verified (but not initialized yet)
169 being_initialized, // currently running class initializer
170 fully_initialized, // initialized (successfull final state)
171 initialization_error // error happened during initialization
172 };
173
174 static int number_of_instance_classes() { return _total_instanceKlass_count; }
175
176 private:
177 static volatile int _total_instanceKlass_count;
178
179 protected:
180 // Protection domain.
181 oop _protection_domain;
182 // Class signers.
183 objArrayOop _signers;
184 // Initialization lock. Must be one per class and it has to be a VM internal
185 // object so java code cannot lock it (like the mirror)
186 // It has to be an object not a Mutex because it's held through java calls.
187 volatile oop _init_lock;
188
189 // Annotations for this class
190 Annotations* _annotations;
191 // Array classes holding elements of this class.
192 Klass* _array_klasses;
193 // Constant pool for this class.
194 ConstantPool* _constants;
195 // The InnerClasses attribute and EnclosingMethod attribute. The
196 // _inner_classes is an array of shorts. If the class has InnerClasses
197 // attribute, then the _inner_classes array begins with 4-tuples of shorts
198 // [inner_class_info_index, outer_class_info_index,
199 // inner_name_index, inner_class_access_flags] for the InnerClasses
200 // attribute. If the EnclosingMethod attribute exists, it occupies the
201 // last two shorts [class_index, method_index] of the array. If only
202 // the InnerClasses attribute exists, the _inner_classes array length is
203 // number_of_inner_classes * 4. If the class has both InnerClasses
204 // and EnclosingMethod attributes the _inner_classes array length is
205 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
206 Array<jushort>* _inner_classes;
207
208 // Name of source file containing this klass, NULL if not specified.
209 Symbol* _source_file_name;
210 // the source debug extension for this klass, NULL if not specified.
211 // Specified as UTF-8 string without terminating zero byte in the classfile,
212 // it is stored in the instanceklass as a NULL-terminated UTF-8 string
213 char* _source_debug_extension;
214 // Generic signature, or null if none.
215 Symbol* _generic_signature;
216 // Array name derived from this class which needs unreferencing
217 // if this class is unloaded.
218 Symbol* _array_name;
219
220 // Number of heapOopSize words used by non-static fields in this klass
221 // (including inherited fields but after header_size()).
222 int _nonstatic_field_size;
223 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
224 u2 _static_oop_field_count;// number of static oop fields in this klass
225 u2 _java_fields_count; // The number of declared Java fields
226 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
227
228 // _is_marked_dependent can be set concurrently, thus cannot be part of the
229 // _misc_flags.
230 bool _is_marked_dependent; // used for marking during flushing and deoptimization
231
232 enum {
233 _misc_rewritten = 1 << 0, // methods rewritten.
234 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
235 _misc_should_verify_class = 1 << 2, // allow caching of preverification
236 _misc_is_anonymous = 1 << 3, // has embedded _inner_classes field
237 _misc_is_contended = 1 << 4, // marked with contended annotation
238 _misc_has_default_methods = 1 << 5 // class/superclass/implemented interfaces has default methods
239 };
240 u2 _misc_flags;
241 u2 _minor_version; // minor version number of class file
242 u2 _major_version; // major version number of class file
243 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
244 int _vtable_len; // length of Java vtable (in words)
245 int _itable_len; // length of Java itable (in words)
246 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
247 JNIid* _jni_ids; // First JNI identifier for static fields in this class
248 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
249 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
250 nmethodBucket* _dependencies; // list of dependent nmethods
251 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
252 BreakpointInfo* _breakpoints; // bpt lists, managed by Method*
253 // Array of interesting part(s) of the previous version(s) of this
254 // InstanceKlass. See PreviousVersionWalker below.
255 GrowableArray<PreviousVersionNode *>* _previous_versions;
256 // JVMTI fields can be moved to their own structure - see 6315920
257 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH
258 jint _cached_class_file_len; // JVMTI: length of above
259
260 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
261
262 // Class states are defined as ClassState (see above).
263 // Place the _init_state here to utilize the unused 2-byte after
264 // _idnum_allocated_count.
265 u1 _init_state; // state of class
266 u1 _reference_type; // reference type
267
268
269 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
270
271 // Method array.
272 Array<Method*>* _methods;
273 // Interface (Klass*s) this class declares locally to implement.
274 Array<Klass*>* _local_interfaces;
275 // Interface (Klass*s) this class implements transitively.
276 Array<Klass*>* _transitive_interfaces;
277 // Int array containing the original order of method in the class file (for JVMTI).
278 Array<int>* _method_ordering;
279 // Instance and static variable information, starts with 6-tuples of shorts
280 // [access, name index, sig index, initval index, low_offset, high_offset]
281 // for all fields, followed by the generic signature data at the end of
282 // the array. Only fields with generic signature attributes have the generic
283 // signature data set in the array. The fields array looks like following:
284 //
285 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
286 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
287 // ...
288 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
289 // [generic signature index]
290 // [generic signature index]
291 // ...
292 Array<u2>* _fields;
293
294 // embedded Java vtable follows here
295 // embedded Java itables follows here
296 // embedded static fields follows here
297 // embedded nonstatic oop-map blocks follows here
298 // embedded implementor of this interface follows here
299 // The embedded implementor only exists if the current klass is an
300 // iterface. The possible values of the implementor fall into following
301 // three cases:
302 // NULL: no implementor.
303 // A Klass* that's not itself: one implementor.
304 // Itsef: more than one implementors.
305 // embedded host klass follows here
306 // The embedded host klass only exists in an anonymous class for
307 // dynamic language support (JSR 292 enabled). The host class grants
308 // its access privileges to this class also. The host class is either
309 // named, or a previously loaded anonymous class. A non-anonymous class
310 // or an anonymous class loaded through normal classloading does not
311 // have this embedded field.
312 //
313
314 friend class SystemDictionary;
315
316 public:
317 bool has_nonstatic_fields() const {
318 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
319 }
320 void set_has_nonstatic_fields(bool b) {
321 if (b) {
322 _misc_flags |= _misc_has_nonstatic_fields;
323 } else {
324 _misc_flags &= ~_misc_has_nonstatic_fields;
325 }
326 }
327
328 // field sizes
329 int nonstatic_field_size() const { return _nonstatic_field_size; }
330 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
331
332 int static_field_size() const { return _static_field_size; }
333 void set_static_field_size(int size) { _static_field_size = size; }
334
335 int static_oop_field_count() const { return (int)_static_oop_field_count; }
336 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
337
338 // Java vtable
339 int vtable_length() const { return _vtable_len; }
340 void set_vtable_length(int len) { _vtable_len = len; }
341
342 // Java itable
343 int itable_length() const { return _itable_len; }
344 void set_itable_length(int len) { _itable_len = len; }
345
346 // array klasses
347 Klass* array_klasses() const { return _array_klasses; }
348 void set_array_klasses(Klass* k) { _array_klasses = k; }
349
350 // methods
351 Array<Method*>* methods() const { return _methods; }
352 void set_methods(Array<Method*>* a) { _methods = a; }
353 Method* method_with_idnum(int idnum);
354
355 // method ordering
356 Array<int>* method_ordering() const { return _method_ordering; }
357 void set_method_ordering(Array<int>* m) { _method_ordering = m; }
358
359 // interfaces
360 Array<Klass*>* local_interfaces() const { return _local_interfaces; }
361 void set_local_interfaces(Array<Klass*>* a) {
362 guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
363 _local_interfaces = a; }
364 Array<Klass*>* transitive_interfaces() const { return _transitive_interfaces; }
365 void set_transitive_interfaces(Array<Klass*>* a) {
366 guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
367 _transitive_interfaces = a; }
368
369 private:
370 friend class fieldDescriptor;
371 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
372
373 public:
374 int field_offset (int index) const { return field(index)->offset(); }
375 int field_access_flags(int index) const { return field(index)->access_flags(); }
376 Symbol* field_name (int index) const { return field(index)->name(constants()); }
377 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
378
379 // Number of Java declared fields
380 int java_fields_count() const { return (int)_java_fields_count; }
381
382 Array<u2>* fields() const { return _fields; }
383
384 void set_fields(Array<u2>* f, u2 java_fields_count) {
385 guarantee(_fields == NULL || f == NULL, "Just checking");
386 _fields = f;
387 _java_fields_count = java_fields_count;
388 }
389
390 // inner classes
391 Array<u2>* inner_classes() const { return _inner_classes; }
392 void set_inner_classes(Array<u2>* f) { _inner_classes = f; }
393
394 enum InnerClassAttributeOffset {
395 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
396 inner_class_inner_class_info_offset = 0,
397 inner_class_outer_class_info_offset = 1,
398 inner_class_inner_name_offset = 2,
399 inner_class_access_flags_offset = 3,
400 inner_class_next_offset = 4
401 };
402
403 enum EnclosingMethodAttributeOffset {
404 enclosing_method_class_index_offset = 0,
405 enclosing_method_method_index_offset = 1,
406 enclosing_method_attribute_size = 2
407 };
408
409 // method override check
410 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
411
412 // package
413 bool is_same_class_package(Klass* class2);
414 bool is_same_class_package(oop classloader2, Symbol* classname2);
415 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
416
417 // find an enclosing class (defined where original code was, in jvm.cpp!)
418 Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
419 instanceKlassHandle self(THREAD, this);
420 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
421 }
422 static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
423 bool* inner_is_member, TRAPS);
424
425 // tell if two classes have the same enclosing class (at package level)
426 bool is_same_package_member(Klass* class2, TRAPS) {
427 instanceKlassHandle self(THREAD, this);
428 return is_same_package_member_impl(self, class2, THREAD);
429 }
430 static bool is_same_package_member_impl(instanceKlassHandle self,
431 Klass* class2, TRAPS);
432
433 // initialization state
434 bool is_loaded() const { return _init_state >= loaded; }
435 bool is_linked() const { return _init_state >= linked; }
436 bool is_initialized() const { return _init_state == fully_initialized; }
437 bool is_not_initialized() const { return _init_state < being_initialized; }
438 bool is_being_initialized() const { return _init_state == being_initialized; }
439 bool is_in_error_state() const { return _init_state == initialization_error; }
440 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
441 ClassState init_state() { return (ClassState)_init_state; }
442 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
443
444 // defineClass specified verification
445 bool should_verify_class() const {
446 return (_misc_flags & _misc_should_verify_class) != 0;
447 }
448 void set_should_verify_class(bool value) {
449 if (value) {
450 _misc_flags |= _misc_should_verify_class;
451 } else {
452 _misc_flags &= ~_misc_should_verify_class;
453 }
454 }
455
456 // marking
457 bool is_marked_dependent() const { return _is_marked_dependent; }
458 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
459
460 // initialization (virtuals from Klass)
461 bool should_be_initialized() const; // means that initialize should be called
462 void initialize(TRAPS);
463 void link_class(TRAPS);
464 bool link_class_or_fail(TRAPS); // returns false on failure
465 void unlink_class();
466 void rewrite_class(TRAPS);
467 void link_methods(TRAPS);
468 Method* class_initializer();
469
470 // set the class to initialized if no static initializer is present
471 void eager_initialize(Thread *thread);
472
473 // reference type
474 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
475 void set_reference_type(ReferenceType t) {
476 assert(t == (u1)t, "overflow");
477 _reference_type = (u1)t;
478 }
479
480 static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
481
482 // find local field, returns true if found
483 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
484 // find field in direct superinterfaces, returns the interface in which the field is defined
485 Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
486 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
487 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
488 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
489 Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
490
491 // find a non-static or static field given its offset within the class.
492 bool contains_field_offset(int offset) {
493 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
494 }
495
496 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
497 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
498
499 // find a local method (returns NULL if not found)
500 Method* find_method(Symbol* name, Symbol* signature) const;
501 static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
502
503 // lookup operation (returns NULL if not found)
504 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const;
505
506 // lookup a method in all the interfaces that this class implements
507 // (returns NULL if not found)
508 Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature) const;
509
510 // Find method indices by name. If a method with the specified name is
511 // found the index to the first method is returned, and 'end' is filled in
512 // with the index of first non-name-matching method. If no method is found
513 // -1 is returned.
514 int find_method_by_name(Symbol* name, int* end);
515 static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
516
517 // constant pool
518 ConstantPool* constants() const { return _constants; }
519 void set_constants(ConstantPool* c) { _constants = c; }
520
521 // protection domain
522 oop protection_domain() { return _protection_domain; }
523 void set_protection_domain(oop pd) { klass_oop_store(&_protection_domain, pd); }
524
525 // host class
526 Klass* host_klass() const {
527 Klass** hk = (Klass**)adr_host_klass();
528 if (hk == NULL) {
529 return NULL;
530 } else {
531 return *hk;
532 }
533 }
534 void set_host_klass(Klass* host) {
535 assert(is_anonymous(), "not anonymous");
536 Klass** addr = (Klass**)adr_host_klass();
537 assert(addr != NULL, "no reversed space");
538 *addr = host;
539 }
540 bool is_anonymous() const {
541 return (_misc_flags & _misc_is_anonymous) != 0;
542 }
543 void set_is_anonymous(bool value) {
544 if (value) {
545 _misc_flags |= _misc_is_anonymous;
546 } else {
547 _misc_flags &= ~_misc_is_anonymous;
548 }
549 }
550
551 // Oop that keeps the metadata for this class from being unloaded
552 // in places where the metadata is stored in other places, like nmethods
553 oop klass_holder() const {
554 return is_anonymous() ? java_mirror() : class_loader();
555 }
556
557 bool is_contended() const {
558 return (_misc_flags & _misc_is_contended) != 0;
559 }
560 void set_is_contended(bool value) {
561 if (value) {
562 _misc_flags |= _misc_is_contended;
563 } else {
564 _misc_flags &= ~_misc_is_contended;
565 }
566 }
567
568 // signers
569 objArrayOop signers() const { return _signers; }
570 void set_signers(objArrayOop s) { klass_oop_store((oop*)&_signers, s); }
571
572 // source file name
573 Symbol* source_file_name() const { return _source_file_name; }
574 void set_source_file_name(Symbol* n);
575
576 // minor and major version numbers of class file
577 u2 minor_version() const { return _minor_version; }
578 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
579 u2 major_version() const { return _major_version; }
580 void set_major_version(u2 major_version) { _major_version = major_version; }
581
582 // source debug extension
583 char* source_debug_extension() const { return _source_debug_extension; }
584 void set_source_debug_extension(char* array, int length);
585
586 // symbol unloading support (refcount already added)
587 Symbol* array_name() { return _array_name; }
588 void set_array_name(Symbol* name) { assert(_array_name == NULL, "name already created"); _array_name = name; }
589
590 // nonstatic oop-map blocks
591 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
592 return oop_map_count * OopMapBlock::size_in_words();
593 }
594 unsigned int nonstatic_oop_map_count() const {
595 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
596 }
597 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
598 void set_nonstatic_oop_map_size(int words) {
599 _nonstatic_oop_map_size = words;
600 }
601
602 // RedefineClasses() support for previous versions:
603 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
604 int emcp_method_count);
605 // If the _previous_versions array is non-NULL, then this klass
606 // has been redefined at least once even if we aren't currently
607 // tracking a previous version.
608 bool has_been_redefined() const { return _previous_versions != NULL; }
609 bool has_previous_version() const;
610 void init_previous_versions() {
611 _previous_versions = NULL;
612 }
613 GrowableArray<PreviousVersionNode *>* previous_versions() const {
614 return _previous_versions;
615 }
616
617 static void purge_previous_versions(InstanceKlass* ik);
618
619 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
620 void set_cached_class_file(unsigned char *class_file_bytes,
621 jint class_file_len) { _cached_class_file_len = class_file_len;
622 _cached_class_file_bytes = class_file_bytes; }
623 jint get_cached_class_file_len() { return _cached_class_file_len; }
624 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; }
625
626 // JVMTI: Support for caching of field indices, types, and offsets
627 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
628 _jvmti_cached_class_field_map = descriptor;
629 }
630 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
631 return _jvmti_cached_class_field_map;
632 }
633
634 bool has_default_methods() const {
635 return (_misc_flags & _misc_has_default_methods) != 0;
636 }
637 void set_has_default_methods(bool b) {
638 if (b) {
639 _misc_flags |= _misc_has_default_methods;
640 } else {
641 _misc_flags &= ~_misc_has_default_methods;
642 }
643 }
644
645 // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
646 inline u2 next_method_idnum();
647 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
648
649 // generics support
650 Symbol* generic_signature() const { return _generic_signature; }
651 void set_generic_signature(Symbol* sig) { _generic_signature = sig; }
652
653 u2 enclosing_method_data(int offset);
654 u2 enclosing_method_class_index() {
655 return enclosing_method_data(enclosing_method_class_index_offset);
656 }
657 u2 enclosing_method_method_index() {
658 return enclosing_method_data(enclosing_method_method_index_offset);
659 }
660 void set_enclosing_method_indices(u2 class_index,
661 u2 method_index);
662
663 // jmethodID support
664 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
665 methodHandle method_h);
666 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
667 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
668 jmethodID* to_dealloc_id_p,
669 jmethodID** to_dealloc_jmeths_p);
670 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
671 size_t *length_p, jmethodID* id_p);
672 jmethodID jmethod_id_or_null(Method* method);
673
674 // cached itable index support
675 void set_cached_itable_index(size_t idnum, int index);
676 int cached_itable_index(size_t idnum);
677
678 // annotations support
679 Annotations* annotations() const { return _annotations; }
680 void set_annotations(Annotations* anno) { _annotations = anno; }
681 AnnotationArray* class_annotations() const {
682 if (annotations() == NULL) return NULL;
683 return annotations()->class_annotations();
684 }
685 Array<AnnotationArray*>* fields_annotations() const {
686 if (annotations() == NULL) return NULL;
687 return annotations()->fields_annotations();
688 }
689 Annotations* type_annotations() const {
690 if (annotations() == NULL) return NULL;
691 return annotations()->type_annotations();
692 }
693
694 // allocation
695 instanceOop allocate_instance(TRAPS);
696
697 // additional member function to return a handle
698 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
699
700 objArrayOop allocate_objArray(int n, int length, TRAPS);
701 // Helper function
702 static instanceOop register_finalizer(instanceOop i, TRAPS);
703
704 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
705 // if not, throw either an Error or an Exception.
706 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
707
708 // initialization
709 void call_class_initializer(TRAPS);
710 void set_initialization_state_and_notify(ClassState state, TRAPS);
711
712 // OopMapCache support
713 OopMapCache* oop_map_cache() { return _oop_map_cache; }
714 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
715 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
716
717 // JNI identifier support (for static fields - for jni performance)
718 JNIid* jni_ids() { return _jni_ids; }
719 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
720 JNIid* jni_id_for(int offset);
721
722 // maintenance of deoptimization dependencies
723 int mark_dependent_nmethods(DepChange& changes);
724 void add_dependent_nmethod(nmethod* nm);
725 void remove_dependent_nmethod(nmethod* nm);
726
727 // On-stack replacement support
728 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
729 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
730 void add_osr_nmethod(nmethod* n);
731 void remove_osr_nmethod(nmethod* n);
732 nmethod* lookup_osr_nmethod(Method* const m, int bci, int level, bool match_level) const;
733
734 // Breakpoint support (see methods on Method* for details)
735 BreakpointInfo* breakpoints() const { return _breakpoints; };
736 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
737
738 // support for stub routines
739 static ByteSize init_state_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
740 TRACE_DEFINE_OFFSET;
741 static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
742
743 // subclass/subinterface checks
744 bool implements_interface(Klass* k) const;
745
746 // Access to the implementor of an interface.
747 Klass* implementor() const
748 {
749 Klass** k = adr_implementor();
750 if (k == NULL) {
751 return NULL;
752 } else {
753 return *k;
754 }
755 }
756
757 void set_implementor(Klass* k) {
758 assert(is_interface(), "not interface");
759 Klass** addr = adr_implementor();
760 *addr = k;
761 }
762
763 int nof_implementors() const {
764 Klass* k = implementor();
765 if (k == NULL) {
766 return 0;
767 } else if (k != this) {
768 return 1;
769 } else {
770 return 2;
771 }
772 }
773
774 void add_implementor(Klass* k); // k is a new class that implements this interface
775 void init_implementor(); // initialize
776
777 // link this class into the implementors list of every interface it implements
778 void process_interfaces(Thread *thread);
779
780 // virtual operations from Klass
781 bool is_leaf_class() const { return _subklass == NULL; }
782 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
783 bool compute_is_subtype_of(Klass* k);
784 bool can_be_primary_super_slow() const;
785 int oop_size(oop obj) const { return size_helper(); }
786 bool oop_is_instance_slow() const { return true; }
787
788 // Iterators
789 void do_local_static_fields(FieldClosure* cl);
790 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
791 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
792
793 void methods_do(void f(Method* method));
794 void array_klasses_do(void f(Klass* k));
795 void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
796 void with_array_klasses_do(void f(Klass* k));
797 bool super_types_do(SuperTypeClosure* blk);
798
799 // Casting from Klass*
800 static InstanceKlass* cast(Klass* k) {
801 assert(k->is_klass(), "must be");
802 assert(k->oop_is_instance(), "cast to InstanceKlass");
803 return (InstanceKlass*) k;
804 }
805
806 InstanceKlass* java_super() const {
807 return (super() == NULL) ? NULL : cast(super());
808 }
809
810 // Sizing (in words)
811 static int header_size() { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
812 static int size(int vtable_length, int itable_length,
813 int nonstatic_oop_map_size,
814 bool is_interface, bool is_anonymous) {
815 return align_object_size(header_size() +
816 align_object_offset(vtable_length) +
817 align_object_offset(itable_length) +
818 ((is_interface || is_anonymous) ?
819 align_object_offset(nonstatic_oop_map_size) :
820 nonstatic_oop_map_size) +
821 (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
822 (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
823 }
824 int size() const { return size(vtable_length(),
825 itable_length(),
826 nonstatic_oop_map_size(),
827 is_interface(),
828 is_anonymous());
829 }
830
831 static int vtable_start_offset() { return header_size(); }
832 static int vtable_length_offset() { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
833
834 intptr_t* start_of_vtable() const { return ((intptr_t*)this) + vtable_start_offset(); }
835 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
836 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
837
838 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
839
840 address static_field_addr(int offset);
841
842 OopMapBlock* start_of_nonstatic_oop_maps() const {
843 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
844 }
845
846 Klass** adr_implementor() const {
847 if (is_interface()) {
848 return (Klass**)(start_of_nonstatic_oop_maps() +
849 nonstatic_oop_map_count());
850 } else {
851 return NULL;
852 }
853 };
854
855 Klass** adr_host_klass() const {
856 if (is_anonymous()) {
857 Klass** adr_impl = adr_implementor();
858 if (adr_impl != NULL) {
859 return adr_impl + 1;
860 } else {
861 return (Klass**)(start_of_nonstatic_oop_maps() +
862 nonstatic_oop_map_count());
863 }
864 } else {
865 return NULL;
866 }
867 }
868
869 // Allocation profiling support
870 juint alloc_size() const { return _alloc_count * size_helper(); }
871 void set_alloc_size(juint n) {}
872
873 // Use this to return the size of an instance in heap words:
874 int size_helper() const {
875 return layout_helper_to_size_helper(layout_helper());
876 }
877
878 // This bit is initialized in classFileParser.cpp.
879 // It is false under any of the following conditions:
880 // - the class is abstract (including any interface)
881 // - the class has a finalizer (if !RegisterFinalizersAtInit)
882 // - the class size is larger than FastAllocateSizeLimit
883 // - the class is java/lang/Class, which cannot be allocated directly
884 bool can_be_fastpath_allocated() const {
885 return !layout_helper_needs_slow_path(layout_helper());
886 }
887
888 // Java vtable/itable
889 klassVtable* vtable() const; // return new klassVtable wrapper
890 inline Method* method_at_vtable(int index);
891 klassItable* itable() const; // return new klassItable wrapper
892 Method* method_at_itable(Klass* holder, int index, TRAPS);
893
894 // Garbage collection
895 virtual void oops_do(OopClosure* cl);
896
897 void oop_follow_contents(oop obj);
898 int oop_adjust_pointers(oop obj);
899
900 void clean_implementors_list(BoolObjectClosure* is_alive);
901 void clean_method_data(BoolObjectClosure* is_alive);
902
903 // Explicit metaspace deallocation of fields
904 // For RedefineClasses, we need to deallocate instanceKlasses
905 void deallocate_contents(ClassLoaderData* loader_data);
906
907 // The constant pool is on stack if any of the methods are executing or
908 // referenced by handles.
909 bool on_stack() const { return _constants->on_stack(); }
910
911 void release_C_heap_structures();
912
913 // Parallel Scavenge and Parallel Old
914 PARALLEL_GC_DECLS
915
916 // Naming
917 const char* signature_name() const;
918
919 // Iterators
920 int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
921 return oop_oop_iterate_v(obj, blk);
922 }
923
924 int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
925 return oop_oop_iterate_v_m(obj, blk, mr);
926 }
927
928 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
929 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
930 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
931 MemRegion mr);
932
933 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
934 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
935
936 #ifndef SERIALGC
937 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
938 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
939
940 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
941 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
942 #endif // !SERIALGC
943
944 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
945 private:
946 // initialization state
947 #ifdef ASSERT
948 void set_init_state(ClassState state);
949 #else
950 void set_init_state(ClassState state) { _init_state = (u1)state; }
951 #endif
952 void set_rewritten() { _misc_flags |= _misc_rewritten; }
953 void set_init_thread(Thread *thread) { _init_thread = thread; }
954
955 // The RedefineClasses() API can cause new method idnums to be needed
956 // which will cause the caches to grow. Safety requires different
957 // cache management logic if the caches can grow instead of just
958 // going from NULL to non-NULL.
959 bool idnum_can_increment() const { return has_been_redefined(); }
960 jmethodID* methods_jmethod_ids_acquire() const
961 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
962 void release_set_methods_jmethod_ids(jmethodID* jmeths)
963 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
964
965 int* methods_cached_itable_indices_acquire() const
966 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
967 void release_set_methods_cached_itable_indices(int* indices)
968 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
969
970 // Lock during initialization
971 volatile oop init_lock() const;
972 void set_init_lock(oop value) { klass_oop_store(&_init_lock, value); }
973 void fence_and_clear_init_lock(); // after fully_initialized
974
975 // Offsets for memory management
976 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
977 oop* adr_signers() const { return (oop*)&this->_signers;}
978 oop* adr_init_lock() const { return (oop*)&this->_init_lock;}
979
980 // Static methods that are used to implement member methods where an exposed this pointer
981 // is needed due to possible GCs
982 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
983 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
984 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
985 static void eager_initialize_impl (instanceKlassHandle this_oop);
986 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
987 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
988 static Klass* array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
989 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
990 /* jni_id_for_impl for jfieldID only */
991 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
992
993 // Returns the array class for the n'th dimension
994 Klass* array_klass_impl(bool or_null, int n, TRAPS);
995
996 // Returns the array class with this class as element type
997 Klass* array_klass_impl(bool or_null, TRAPS);
998
999 public:
1000 // CDS support - remove and restore oops from metadata. Oops are not shared.
1001 virtual void remove_unshareable_info();
1002 virtual void restore_unshareable_info(TRAPS);
1003
1004 // jvm support
1005 jint compute_modifier_flags(TRAPS) const;
1006
1007 public:
1008 // JVMTI support
1009 jint jvmti_class_status() const;
1010
1011 public:
1012 // Printing
1013 #ifndef PRODUCT
1014 void print_on(outputStream* st) const;
1015 #endif
1016 void print_value_on(outputStream* st) const;
1017
1018 void oop_print_value_on(oop obj, outputStream* st);
1019
1020 #ifndef PRODUCT
1021 void oop_print_on (oop obj, outputStream* st);
1022
1023 void print_dependent_nmethods(bool verbose = false);
1024 bool is_dependent_nmethod(nmethod* nm);
1025 #endif
1026
1027 const char* internal_name() const;
1028
1029 // Verification
1030 void verify_on(outputStream* st);
1031
1032 void oop_verify_on(oop obj, outputStream* st);
1033 };
1034
1035 inline Method* InstanceKlass::method_at_vtable(int index) {
1036 #ifndef PRODUCT
1037 assert(index >= 0, "valid vtable index");
1038 if (DebugVtables) {
1039 verify_vtable_index(index);
1040 }
1041 #endif
1042 vtableEntry* ve = (vtableEntry*)start_of_vtable();
1043 return ve[index].method();
1044 }
1045
1046 // for adding methods
1047 // UNSET_IDNUM return means no more ids available
1048 inline u2 InstanceKlass::next_method_idnum() {
1049 if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1050 return ConstMethod::UNSET_IDNUM; // no more ids available
1051 } else {
1052 return _idnum_allocated_count++;
1053 }
1054 }
1055
1056
1057 /* JNIid class for jfieldIDs only */
1058 class JNIid: public CHeapObj<mtClass> {
1059 friend class VMStructs;
1060 private:
1061 Klass* _holder;
1062 JNIid* _next;
1063 int _offset;
1064 #ifdef ASSERT
1065 bool _is_static_field_id;
1066 #endif
1067
1068 public:
1069 // Accessors
1070 Klass* holder() const { return _holder; }
1071 int offset() const { return _offset; }
1072 JNIid* next() { return _next; }
1073 // Constructor
1074 JNIid(Klass* holder, int offset, JNIid* next);
1075 // Identifier lookup
1076 JNIid* find(int offset);
1077
1078 bool find_local_field(fieldDescriptor* fd) {
1079 return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1080 }
1081
1082 static void deallocate(JNIid* id);
1083 // Debugging
1084 #ifdef ASSERT
1085 bool is_static_field_id() const { return _is_static_field_id; }
1086 void set_is_static_field_id() { _is_static_field_id = true; }
1087 #endif
1088 void verify(Klass* holder);
1089 };
1090
1091
1092 // If breakpoints are more numerous than just JVMTI breakpoints,
1093 // consider compressing this data structure.
1094 // It is currently a simple linked list defined in method.hpp.
1095
1096 class BreakpointInfo;
1097
1098
1099 // A collection point for interesting information about the previous
1100 // version(s) of an InstanceKlass. This class uses weak references to
1101 // the information so that the information may be collected as needed
1102 // by the system. If the information is shared, then a regular
1103 // reference must be used because a weak reference would be seen as
1104 // collectible. A GrowableArray of PreviousVersionNodes is attached
1105 // to the InstanceKlass as needed. See PreviousVersionWalker below.
1106 class PreviousVersionNode : public CHeapObj<mtClass> {
1107 private:
1108 // A shared ConstantPool is never collected so we'll always have
1109 // a reference to it so we can update items in the cache. We'll
1110 // have a weak reference to a non-shared ConstantPool until all
1111 // of the methods (EMCP or obsolete) have been collected; the
1112 // non-shared ConstantPool becomes collectible at that point.
1113 ConstantPool* _prev_constant_pool; // regular or weak reference
1114 bool _prev_cp_is_weak; // true if not a shared ConstantPool
1115
1116 // If the previous version of the InstanceKlass doesn't have any
1117 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1118 // EMCP methods have been collected, then _prev_EMCP_methods can
1119 // have a length of zero.
1120 GrowableArray<Method*>* _prev_EMCP_methods;
1121
1122 public:
1123 PreviousVersionNode(ConstantPool* prev_constant_pool, bool prev_cp_is_weak,
1124 GrowableArray<Method*>* prev_EMCP_methods);
1125 ~PreviousVersionNode();
1126 ConstantPool* prev_constant_pool() const {
1127 return _prev_constant_pool;
1128 }
1129 GrowableArray<Method*>* prev_EMCP_methods() const {
1130 return _prev_EMCP_methods;
1131 }
1132 };
1133
1134
1135 // A Handle-ized version of PreviousVersionNode.
1136 class PreviousVersionInfo : public ResourceObj {
1137 private:
1138 constantPoolHandle _prev_constant_pool_handle;
1139 // If the previous version of the InstanceKlass doesn't have any
1140 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
1141 // methods cannot be collected while we hold a handle,
1142 // _prev_EMCP_methods should never have a length of zero.
1143 GrowableArray<methodHandle>* _prev_EMCP_method_handles;
1144
1145 public:
1146 PreviousVersionInfo(PreviousVersionNode *pv_node);
1147 ~PreviousVersionInfo();
1148 constantPoolHandle prev_constant_pool_handle() const {
1149 return _prev_constant_pool_handle;
1150 }
1151 GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
1152 return _prev_EMCP_method_handles;
1153 }
1154 };
1155
1156
1157 // Helper object for walking previous versions. This helper cleans up
1158 // the Handles that it allocates when the helper object is destroyed.
1159 // The PreviousVersionInfo object returned by next_previous_version()
1160 // is only valid until a subsequent call to next_previous_version() or
1161 // the helper object is destroyed.
1162 class PreviousVersionWalker : public StackObj {
1163 private:
1164 GrowableArray<PreviousVersionNode *>* _previous_versions;
1165 int _current_index;
1166 // Fields for cleaning up when we are done walking the previous versions:
1167 // A HandleMark for the PreviousVersionInfo handles:
1168 HandleMark _hm;
1169
1170 // It would be nice to have a ResourceMark field in this helper also,
1171 // but the ResourceMark code says to be careful to delete handles held
1172 // in GrowableArrays _before_ deleting the GrowableArray. Since we
1173 // can't guarantee the order in which the fields are destroyed, we
1174 // have to let the creator of the PreviousVersionWalker object do
1175 // the right thing. Also, adding a ResourceMark here causes an
1176 // include loop.
1177
1178 // A pointer to the current info object so we can handle the deletes.
1179 PreviousVersionInfo * _current_p;
1180
1181 public:
1182 PreviousVersionWalker(InstanceKlass *ik);
1183 ~PreviousVersionWalker();
1184
1185 // Return the interesting information for the next previous version
1186 // of the klass. Returns NULL if there are no more previous versions.
1187 PreviousVersionInfo* next_previous_version();
1188 };
1189
1190
1191 //
1192 // nmethodBucket is used to record dependent nmethods for
1193 // deoptimization. nmethod dependencies are actually <klass, method>
1194 // pairs but we really only care about the klass part for purposes of
1195 // finding nmethods which might need to be deoptimized. Instead of
1196 // recording the method, a count of how many times a particular nmethod
1197 // was recorded is kept. This ensures that any recording errors are
1198 // noticed since an nmethod should be removed as many times are it's
1199 // added.
1200 //
1201 class nmethodBucket: public CHeapObj<mtClass> {
1202 friend class VMStructs;
1203 private:
1204 nmethod* _nmethod;
1205 int _count;
1206 nmethodBucket* _next;
1207
1208 public:
1209 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1210 _nmethod = nmethod;
1211 _next = next;
1212 _count = 1;
1213 }
1214 int count() { return _count; }
1215 int increment() { _count += 1; return _count; }
1216 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1217 nmethodBucket* next() { return _next; }
1218 void set_next(nmethodBucket* b) { _next = b; }
1219 nmethod* get_nmethod() { return _nmethod; }
1220 };
1221
1222 // An iterator that's used to access the inner classes indices in the
1223 // InstanceKlass::_inner_classes array.
1224 class InnerClassesIterator : public StackObj {
1225 private:
1226 Array<jushort>* _inner_classes;
1227 int _length;
1228 int _idx;
1229 public:
1230
1231 InnerClassesIterator(instanceKlassHandle k) {
1232 _inner_classes = k->inner_classes();
1233 if (k->inner_classes() != NULL) {
1234 _length = _inner_classes->length();
1235 // The inner class array's length should be the multiple of
1236 // inner_class_next_offset if it only contains the InnerClasses
1237 // attribute data, or it should be
1238 // n*inner_class_next_offset+enclosing_method_attribute_size
1239 // if it also contains the EnclosingMethod data.
1240 assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1241 _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1242 "just checking");
1243 // Remove the enclosing_method portion if exists.
1244 if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1245 _length -= InstanceKlass::enclosing_method_attribute_size;
1246 }
1247 } else {
1248 _length = 0;
1249 }
1250 _idx = 0;
1251 }
1252
1253 int length() const {
1254 return _length;
1255 }
1256
1257 void next() {
1258 _idx += InstanceKlass::inner_class_next_offset;
1259 }
1260
1261 bool done() const {
1262 return (_idx >= _length);
1263 }
1264
1265 u2 inner_class_info_index() const {
1266 return _inner_classes->at(
1267 _idx + InstanceKlass::inner_class_inner_class_info_offset);
1268 }
1269
1270 void set_inner_class_info_index(u2 index) {
1271 _inner_classes->at_put(
1272 _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1273 }
1274
1275 u2 outer_class_info_index() const {
1276 return _inner_classes->at(
1277 _idx + InstanceKlass::inner_class_outer_class_info_offset);
1278 }
1279
1280 void set_outer_class_info_index(u2 index) {
1281 _inner_classes->at_put(
1282 _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1283 }
1284
1285 u2 inner_name_index() const {
1286 return _inner_classes->at(
1287 _idx + InstanceKlass::inner_class_inner_name_offset);
1288 }
1289
1290 void set_inner_name_index(u2 index) {
1291 _inner_classes->at_put(
1292 _idx + InstanceKlass::inner_class_inner_name_offset, index);
1293 }
1294
1295 u2 inner_access_flags() const {
1296 return _inner_classes->at(
1297 _idx + InstanceKlass::inner_class_access_flags_offset);
1298 }
1299 };
1300
1301 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP