Thu, 28 Jun 2012 17:03:16 -0400
6995781: Native Memory Tracking (Phase 1)
7151532: DCmd for hotspot native memory tracking
Summary: Implementation of native memory tracking phase 1, which tracks VM native memory usage, and related DCmd
Reviewed-by: acorn, coleenp, fparain
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 */
25 #ifndef SHARE_VM_OOPS_INSTANCEKLASS_HPP
26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
28 #include "oops/constMethodOop.hpp"
29 #include "oops/constantPoolOop.hpp"
30 #include "oops/fieldInfo.hpp"
31 #include "oops/instanceOop.hpp"
32 #include "oops/klassOop.hpp"
33 #include "oops/klassVtable.hpp"
34 #include "oops/objArrayOop.hpp"
35 #include "runtime/handles.hpp"
36 #include "runtime/os.hpp"
37 #include "utilities/accessFlags.hpp"
38 #include "utilities/bitMap.inline.hpp"
40 // An instanceKlass is the VM level representation of a Java class.
41 // It contains all information needed for at class at execution runtime.
43 // instanceKlass layout:
44 // [header ] klassOop
45 // [klass pointer ] klassOop
46 // [C++ vtbl pointer ] Klass
47 // [subtype cache ] Klass
48 // [instance size ] Klass
49 // [java mirror ] Klass
50 // [super ] Klass
51 // [access_flags ] Klass
52 // [name ] Klass
53 // [first subklass ] Klass
54 // [next sibling ] Klass
55 // [array klasses ]
56 // [methods ]
57 // [local interfaces ]
58 // [transitive interfaces ]
59 // [fields ]
60 // [constants ]
61 // [class loader ]
62 // [protection domain ]
63 // [signers ]
64 // [source file name ]
65 // [inner classes ]
66 // [static field size ]
67 // [nonstatic field size ]
68 // [static oop fields size ]
69 // [nonstatic oop maps size ]
70 // [has finalize method ]
71 // [deoptimization mark bit ]
72 // [initialization state ]
73 // [initializing thread ]
74 // [Java vtable length ]
75 // [oop map cache (stack maps) ]
76 // [EMBEDDED Java vtable ] size in words = vtable_len
77 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
78 // The embedded nonstatic oop-map blocks are short pairs (offset, length)
79 // indicating where oops are located in instances of this klass.
80 // [EMBEDDED implementor of the interface] only exist for interface
81 // [EMBEDDED host klass ] only exist for an anonymous class (JSR 292 enabled)
84 // forward declaration for class -- see below for definition
85 class SuperTypeClosure;
86 class JNIid;
87 class jniIdMapBase;
88 class BreakpointInfo;
89 class fieldDescriptor;
90 class DepChange;
91 class nmethodBucket;
92 class PreviousVersionNode;
93 class JvmtiCachedClassFieldMap;
95 // This is used in iterators below.
96 class FieldClosure: public StackObj {
97 public:
98 virtual void do_field(fieldDescriptor* fd) = 0;
99 };
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
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; }
121 // Number of oops in this block.
122 uint count() const { return _count; }
123 void set_count(uint count) { _count = count; }
125 // sizeof(OopMapBlock) in HeapWords.
126 static const int size_in_words() {
127 return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
128 LogHeapWordSize;
129 }
131 private:
132 int _offset;
133 uint _count;
134 };
136 class instanceKlass: public Klass {
137 friend class VMStructs;
138 public:
139 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
140 // of the class loading & initialization procedure, and the use of the states.
141 enum ClassState {
142 unparsable_by_gc = 0, // object is not yet parsable by gc. Value of _init_state at object allocation.
143 allocated, // allocated (but not yet linked)
144 loaded, // loaded and inserted in class hierarchy (but not linked yet)
145 linked, // successfully linked/verified (but not initialized yet)
146 being_initialized, // currently running class initializer
147 fully_initialized, // initialized (successfull final state)
148 initialization_error // error happened during initialization
149 };
151 public:
152 oop* oop_block_beg() const { return adr_array_klasses(); }
153 oop* oop_block_end() const { return adr_methods_default_annotations() + 1; }
155 protected:
156 //
157 // The oop block. See comment in klass.hpp before making changes.
158 //
160 // Array classes holding elements of this class.
161 klassOop _array_klasses;
162 // Method array.
163 objArrayOop _methods;
164 // Int array containing the original order of method in the class file (for
165 // JVMTI).
166 typeArrayOop _method_ordering;
167 // Interface (klassOops) this class declares locally to implement.
168 objArrayOop _local_interfaces;
169 // Interface (klassOops) this class implements transitively.
170 objArrayOop _transitive_interfaces;
171 // Instance and static variable information, starts with 6-tuples of shorts
172 // [access, name index, sig index, initval index, low_offset, high_offset]
173 // for all fields, followed by the generic signature data at the end of
174 // the array. Only fields with generic signature attributes have the generic
175 // signature data set in the array. The fields array looks like following:
176 //
177 // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
178 // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
179 // ...
180 // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
181 // [generic signature index]
182 // [generic signature index]
183 // ...
184 typeArrayOop _fields;
185 // Constant pool for this class.
186 constantPoolOop _constants;
187 // Class loader used to load this class, NULL if VM loader used.
188 oop _class_loader;
189 // Protection domain.
190 oop _protection_domain;
191 // Class signers.
192 objArrayOop _signers;
193 // The InnerClasses attribute and EnclosingMethod attribute. The
194 // _inner_classes is an array of shorts. If the class has InnerClasses
195 // attribute, then the _inner_classes array begins with 4-tuples of shorts
196 // [inner_class_info_index, outer_class_info_index,
197 // inner_name_index, inner_class_access_flags] for the InnerClasses
198 // attribute. If the EnclosingMethod attribute exists, it occupies the
199 // last two shorts [class_index, method_index] of the array. If only
200 // the InnerClasses attribute exists, the _inner_classes array length is
201 // number_of_inner_classes * 4. If the class has both InnerClasses
202 // and EnclosingMethod attributes the _inner_classes array length is
203 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
204 typeArrayOop _inner_classes;
205 // Annotations for this class, or null if none.
206 typeArrayOop _class_annotations;
207 // Annotation objects (byte arrays) for fields, or null if no annotations.
208 // Indices correspond to entries (not indices) in fields array.
209 objArrayOop _fields_annotations;
210 // Annotation objects (byte arrays) for methods, or null if no annotations.
211 // Index is the idnum, which is initially the same as the methods array index.
212 objArrayOop _methods_annotations;
213 // Annotation objects (byte arrays) for methods' parameters, or null if no
214 // such annotations.
215 // Index is the idnum, which is initially the same as the methods array index.
216 objArrayOop _methods_parameter_annotations;
217 // Annotation objects (byte arrays) for methods' default values, or null if no
218 // such annotations.
219 // Index is the idnum, which is initially the same as the methods array index.
220 objArrayOop _methods_default_annotations;
222 //
223 // End of the oop block.
224 //
226 // Name of source file containing this klass, NULL if not specified.
227 Symbol* _source_file_name;
228 // the source debug extension for this klass, NULL if not specified.
229 Symbol* _source_debug_extension;
230 // Generic signature, or null if none.
231 Symbol* _generic_signature;
232 // Array name derived from this class which needs unreferencing
233 // if this class is unloaded.
234 Symbol* _array_name;
236 // Number of heapOopSize words used by non-static fields in this klass
237 // (including inherited fields but after header_size()).
238 int _nonstatic_field_size;
239 int _static_field_size; // number words used by static fields (oop and non-oop) in this klass
240 u2 _static_oop_field_count;// number of static oop fields in this klass
241 u2 _java_fields_count; // The number of declared Java fields
242 int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
244 bool _is_marked_dependent; // used for marking during flushing and deoptimization
245 enum {
246 _misc_rewritten = 1 << 0, // methods rewritten.
247 _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
248 _misc_should_verify_class = 1 << 2, // allow caching of preverification
249 _misc_is_anonymous = 1 << 3 // has embedded _inner_classes field
250 };
251 u2 _misc_flags;
252 u2 _minor_version; // minor version number of class file
253 u2 _major_version; // major version number of class file
254 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization)
255 int _vtable_len; // length of Java vtable (in words)
256 int _itable_len; // length of Java itable (in words)
257 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily)
258 JNIid* _jni_ids; // First JNI identifier for static fields in this class
259 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none
260 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
261 nmethodBucket* _dependencies; // list of dependent nmethods
262 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class
263 BreakpointInfo* _breakpoints; // bpt lists, managed by methodOop
264 // Array of interesting part(s) of the previous version(s) of this
265 // instanceKlass. See PreviousVersionWalker below.
266 GrowableArray<PreviousVersionNode *>* _previous_versions;
267 // JVMTI fields can be moved to their own structure - see 6315920
268 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH
269 jint _cached_class_file_len; // JVMTI: length of above
270 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration
271 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change
273 // Class states are defined as ClassState (see above).
274 // Place the _init_state here to utilize the unused 2-byte after
275 // _idnum_allocated_count.
276 u1 _init_state; // state of class
278 u1 _reference_type; // reference type
280 // embedded Java vtable follows here
281 // embedded Java itables follows here
282 // embedded static fields follows here
283 // embedded nonstatic oop-map blocks follows here
284 // embedded implementor of this interface follows here
285 // The embedded implementor only exists if the current klass is an
286 // iterface. The possible values of the implementor fall into following
287 // three cases:
288 // NULL: no implementor.
289 // A klassOop that's not itself: one implementor.
290 // Itsef: more than one implementors.
291 // embedded host klass follows here
292 // The embedded host klass only exists in an anonymous class for
293 // dynamic language support (JSR 292 enabled). The host class grants
294 // its access privileges to this class also. The host class is either
295 // named, or a previously loaded anonymous class. A non-anonymous class
296 // or an anonymous class loaded through normal classloading does not
297 // have this embedded field.
298 //
300 friend class instanceKlassKlass;
301 friend class SystemDictionary;
303 public:
304 bool has_nonstatic_fields() const {
305 return (_misc_flags & _misc_has_nonstatic_fields) != 0;
306 }
307 void set_has_nonstatic_fields(bool b) {
308 if (b) {
309 _misc_flags |= _misc_has_nonstatic_fields;
310 } else {
311 _misc_flags &= ~_misc_has_nonstatic_fields;
312 }
313 }
315 // field sizes
316 int nonstatic_field_size() const { return _nonstatic_field_size; }
317 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; }
319 int static_field_size() const { return _static_field_size; }
320 void set_static_field_size(int size) { _static_field_size = size; }
322 int static_oop_field_count() const { return (int)_static_oop_field_count; }
323 void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
325 // Java vtable
326 int vtable_length() const { return _vtable_len; }
327 void set_vtable_length(int len) { _vtable_len = len; }
329 // Java itable
330 int itable_length() const { return _itable_len; }
331 void set_itable_length(int len) { _itable_len = len; }
333 // array klasses
334 klassOop array_klasses() const { return _array_klasses; }
335 void set_array_klasses(klassOop k) { oop_store_without_check((oop*) &_array_klasses, (oop) k); }
337 // methods
338 objArrayOop methods() const { return _methods; }
339 void set_methods(objArrayOop a) { oop_store_without_check((oop*) &_methods, (oop) a); }
340 methodOop method_with_idnum(int idnum);
342 // method ordering
343 typeArrayOop method_ordering() const { return _method_ordering; }
344 void set_method_ordering(typeArrayOop m) { oop_store_without_check((oop*) &_method_ordering, (oop) m); }
346 // interfaces
347 objArrayOop local_interfaces() const { return _local_interfaces; }
348 void set_local_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_local_interfaces, (oop) a); }
349 objArrayOop transitive_interfaces() const { return _transitive_interfaces; }
350 void set_transitive_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_transitive_interfaces, (oop) a); }
352 private:
353 friend class fieldDescriptor;
354 FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
356 public:
357 int field_offset (int index) const { return field(index)->offset(); }
358 int field_access_flags(int index) const { return field(index)->access_flags(); }
359 Symbol* field_name (int index) const { return field(index)->name(constants()); }
360 Symbol* field_signature (int index) const { return field(index)->signature(constants()); }
362 // Number of Java declared fields
363 int java_fields_count() const { return (int)_java_fields_count; }
365 typeArrayOop fields() const { return _fields; }
367 void set_fields(typeArrayOop f, u2 java_fields_count) {
368 oop_store_without_check((oop*) &_fields, (oop) f);
369 _java_fields_count = java_fields_count;
370 }
372 // inner classes
373 typeArrayOop inner_classes() const { return _inner_classes; }
374 void set_inner_classes(typeArrayOop f) { oop_store_without_check((oop*) &_inner_classes, (oop) f); }
376 enum InnerClassAttributeOffset {
377 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
378 inner_class_inner_class_info_offset = 0,
379 inner_class_outer_class_info_offset = 1,
380 inner_class_inner_name_offset = 2,
381 inner_class_access_flags_offset = 3,
382 inner_class_next_offset = 4
383 };
385 enum EnclosingMethodAttributeOffset {
386 enclosing_method_class_index_offset = 0,
387 enclosing_method_method_index_offset = 1,
388 enclosing_method_attribute_size = 2
389 };
391 // method override check
392 bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
394 // package
395 bool is_same_class_package(klassOop class2);
396 bool is_same_class_package(oop classloader2, Symbol* classname2);
397 static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
399 // find an enclosing class (defined where original code was, in jvm.cpp!)
400 klassOop compute_enclosing_class(bool* inner_is_member, TRAPS) {
401 instanceKlassHandle self(THREAD, this->as_klassOop());
402 return compute_enclosing_class_impl(self, inner_is_member, THREAD);
403 }
404 static klassOop compute_enclosing_class_impl(instanceKlassHandle self,
405 bool* inner_is_member, TRAPS);
407 // tell if two classes have the same enclosing class (at package level)
408 bool is_same_package_member(klassOop class2, TRAPS) {
409 instanceKlassHandle self(THREAD, this->as_klassOop());
410 return is_same_package_member_impl(self, class2, THREAD);
411 }
412 static bool is_same_package_member_impl(instanceKlassHandle self,
413 klassOop class2, TRAPS);
415 // initialization state
416 bool is_loaded() const { return _init_state >= loaded; }
417 bool is_linked() const { return _init_state >= linked; }
418 bool is_initialized() const { return _init_state == fully_initialized; }
419 bool is_not_initialized() const { return _init_state < being_initialized; }
420 bool is_being_initialized() const { return _init_state == being_initialized; }
421 bool is_in_error_state() const { return _init_state == initialization_error; }
422 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; }
423 ClassState init_state() { return (ClassState)_init_state; }
424 bool is_rewritten() const { return (_misc_flags & _misc_rewritten) != 0; }
426 // defineClass specified verification
427 bool should_verify_class() const {
428 return (_misc_flags & _misc_should_verify_class) != 0;
429 }
430 void set_should_verify_class(bool value) {
431 if (value) {
432 _misc_flags |= _misc_should_verify_class;
433 } else {
434 _misc_flags &= ~_misc_should_verify_class;
435 }
436 }
438 // marking
439 bool is_marked_dependent() const { return _is_marked_dependent; }
440 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
442 // initialization (virtuals from Klass)
443 bool should_be_initialized() const; // means that initialize should be called
444 void initialize(TRAPS);
445 void link_class(TRAPS);
446 bool link_class_or_fail(TRAPS); // returns false on failure
447 void unlink_class();
448 void rewrite_class(TRAPS);
449 void relocate_and_link_methods(TRAPS);
450 methodOop class_initializer();
452 // set the class to initialized if no static initializer is present
453 void eager_initialize(Thread *thread);
455 // reference type
456 ReferenceType reference_type() const { return (ReferenceType)_reference_type; }
457 void set_reference_type(ReferenceType t) {
458 assert(t == (u1)t, "overflow");
459 _reference_type = (u1)t;
460 }
462 static ByteSize reference_type_offset() { return in_ByteSize(sizeof(klassOopDesc) + offset_of(instanceKlass, _reference_type)); }
464 // find local field, returns true if found
465 bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
466 // find field in direct superinterfaces, returns the interface in which the field is defined
467 klassOop find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
468 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
469 klassOop find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
470 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
471 klassOop find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
473 // find a non-static or static field given its offset within the class.
474 bool contains_field_offset(int offset) {
475 return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
476 }
478 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
479 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
481 // find a local method (returns NULL if not found)
482 methodOop find_method(Symbol* name, Symbol* signature) const;
483 static methodOop find_method(objArrayOop methods, Symbol* name, Symbol* signature);
485 // lookup operation (returns NULL if not found)
486 methodOop uncached_lookup_method(Symbol* name, Symbol* signature) const;
488 // lookup a method in all the interfaces that this class implements
489 // (returns NULL if not found)
490 methodOop lookup_method_in_all_interfaces(Symbol* name, Symbol* signature) const;
492 // constant pool
493 constantPoolOop constants() const { return _constants; }
494 void set_constants(constantPoolOop c) { oop_store_without_check((oop*) &_constants, (oop) c); }
496 // class loader
497 oop class_loader() const { return _class_loader; }
498 void set_class_loader(oop l) { oop_store((oop*) &_class_loader, l); }
500 // protection domain
501 oop protection_domain() { return _protection_domain; }
502 void set_protection_domain(oop pd) { oop_store((oop*) &_protection_domain, pd); }
504 // host class
505 oop host_klass() const {
506 oop* hk = adr_host_klass();
507 if (hk == NULL) {
508 return NULL;
509 } else {
510 return *hk;
511 }
512 }
513 void set_host_klass(oop host) {
514 assert(is_anonymous(), "not anonymous");
515 oop* addr = adr_host_klass();
516 assert(addr != NULL, "no reversed space");
517 oop_store(addr, host);
518 }
519 bool is_anonymous() const {
520 return (_misc_flags & _misc_is_anonymous) != 0;
521 }
522 void set_is_anonymous(bool value) {
523 if (value) {
524 _misc_flags |= _misc_is_anonymous;
525 } else {
526 _misc_flags &= ~_misc_is_anonymous;
527 }
528 }
530 // signers
531 objArrayOop signers() const { return _signers; }
532 void set_signers(objArrayOop s) { oop_store((oop*) &_signers, oop(s)); }
534 // source file name
535 Symbol* source_file_name() const { return _source_file_name; }
536 void set_source_file_name(Symbol* n);
538 // minor and major version numbers of class file
539 u2 minor_version() const { return _minor_version; }
540 void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
541 u2 major_version() const { return _major_version; }
542 void set_major_version(u2 major_version) { _major_version = major_version; }
544 // source debug extension
545 Symbol* source_debug_extension() const { return _source_debug_extension; }
546 void set_source_debug_extension(Symbol* n);
548 // symbol unloading support (refcount already added)
549 Symbol* array_name() { return _array_name; }
550 void set_array_name(Symbol* name) { assert(_array_name == NULL, "name already created"); _array_name = name; }
552 // nonstatic oop-map blocks
553 static int nonstatic_oop_map_size(unsigned int oop_map_count) {
554 return oop_map_count * OopMapBlock::size_in_words();
555 }
556 unsigned int nonstatic_oop_map_count() const {
557 return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
558 }
559 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
560 void set_nonstatic_oop_map_size(int words) {
561 _nonstatic_oop_map_size = words;
562 }
564 // RedefineClasses() support for previous versions:
565 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
566 int emcp_method_count);
567 // If the _previous_versions array is non-NULL, then this klass
568 // has been redefined at least once even if we aren't currently
569 // tracking a previous version.
570 bool has_been_redefined() const { return _previous_versions != NULL; }
571 bool has_previous_version() const;
572 void init_previous_versions() {
573 _previous_versions = NULL;
574 }
575 GrowableArray<PreviousVersionNode *>* previous_versions() const {
576 return _previous_versions;
577 }
579 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
580 void set_cached_class_file(unsigned char *class_file_bytes,
581 jint class_file_len) { _cached_class_file_len = class_file_len;
582 _cached_class_file_bytes = class_file_bytes; }
583 jint get_cached_class_file_len() { return _cached_class_file_len; }
584 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; }
586 // JVMTI: Support for caching of field indices, types, and offsets
587 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
588 _jvmti_cached_class_field_map = descriptor;
589 }
590 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
591 return _jvmti_cached_class_field_map;
592 }
594 // for adding methods, constMethodOopDesc::UNSET_IDNUM means no more ids available
595 inline u2 next_method_idnum();
596 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; }
598 // generics support
599 Symbol* generic_signature() const { return _generic_signature; }
600 void set_generic_signature(Symbol* sig) { _generic_signature = sig; }
602 u2 enclosing_method_data(int offset);
603 u2 enclosing_method_class_index() {
604 return enclosing_method_data(enclosing_method_class_index_offset);
605 }
606 u2 enclosing_method_method_index() {
607 return enclosing_method_data(enclosing_method_method_index_offset);
608 }
609 void set_enclosing_method_indices(u2 class_index,
610 u2 method_index);
612 // jmethodID support
613 static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
614 methodHandle method_h);
615 static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
616 size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
617 jmethodID* to_dealloc_id_p,
618 jmethodID** to_dealloc_jmeths_p);
619 static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
620 size_t *length_p, jmethodID* id_p);
621 jmethodID jmethod_id_or_null(methodOop method);
623 // cached itable index support
624 void set_cached_itable_index(size_t idnum, int index);
625 int cached_itable_index(size_t idnum);
627 // annotations support
628 typeArrayOop class_annotations() const { return _class_annotations; }
629 objArrayOop fields_annotations() const { return _fields_annotations; }
630 objArrayOop methods_annotations() const { return _methods_annotations; }
631 objArrayOop methods_parameter_annotations() const { return _methods_parameter_annotations; }
632 objArrayOop methods_default_annotations() const { return _methods_default_annotations; }
633 void set_class_annotations(typeArrayOop md) { oop_store_without_check((oop*)&_class_annotations, (oop)md); }
634 void set_fields_annotations(objArrayOop md) { set_annotations(md, &_fields_annotations); }
635 void set_methods_annotations(objArrayOop md) { set_annotations(md, &_methods_annotations); }
636 void set_methods_parameter_annotations(objArrayOop md) { set_annotations(md, &_methods_parameter_annotations); }
637 void set_methods_default_annotations(objArrayOop md) { set_annotations(md, &_methods_default_annotations); }
638 typeArrayOop get_method_annotations_of(int idnum)
639 { return get_method_annotations_from(idnum, _methods_annotations); }
640 typeArrayOop get_method_parameter_annotations_of(int idnum)
641 { return get_method_annotations_from(idnum, _methods_parameter_annotations); }
642 typeArrayOop get_method_default_annotations_of(int idnum)
643 { return get_method_annotations_from(idnum, _methods_default_annotations); }
644 void set_method_annotations_of(int idnum, typeArrayOop anno)
645 { set_methods_annotations_of(idnum, anno, &_methods_annotations); }
646 void set_method_parameter_annotations_of(int idnum, typeArrayOop anno)
647 { set_methods_annotations_of(idnum, anno, &_methods_parameter_annotations); }
648 void set_method_default_annotations_of(int idnum, typeArrayOop anno)
649 { set_methods_annotations_of(idnum, anno, &_methods_default_annotations); }
651 // allocation
652 DEFINE_ALLOCATE_PERMANENT(instanceKlass);
653 instanceOop allocate_instance(TRAPS);
654 instanceOop allocate_permanent_instance(TRAPS);
656 // additional member function to return a handle
657 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); }
659 objArrayOop allocate_objArray(int n, int length, TRAPS);
660 // Helper function
661 static instanceOop register_finalizer(instanceOop i, TRAPS);
663 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
664 // if not, throw either an Error or an Exception.
665 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
667 // initialization
668 void call_class_initializer(TRAPS);
669 void set_initialization_state_and_notify(ClassState state, TRAPS);
671 // OopMapCache support
672 OopMapCache* oop_map_cache() { return _oop_map_cache; }
673 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
674 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
676 // JNI identifier support (for static fields - for jni performance)
677 JNIid* jni_ids() { return _jni_ids; }
678 void set_jni_ids(JNIid* ids) { _jni_ids = ids; }
679 JNIid* jni_id_for(int offset);
681 // maintenance of deoptimization dependencies
682 int mark_dependent_nmethods(DepChange& changes);
683 void add_dependent_nmethod(nmethod* nm);
684 void remove_dependent_nmethod(nmethod* nm);
686 // On-stack replacement support
687 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; };
688 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; };
689 void add_osr_nmethod(nmethod* n);
690 void remove_osr_nmethod(nmethod* n);
691 nmethod* lookup_osr_nmethod(const methodOop m, int bci, int level, bool match_level) const;
693 // Breakpoint support (see methods on methodOop for details)
694 BreakpointInfo* breakpoints() const { return _breakpoints; };
695 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
697 // support for stub routines
698 static ByteSize init_state_offset() { return in_ByteSize(sizeof(klassOopDesc) + offset_of(instanceKlass, _init_state)); }
699 TRACE_DEFINE_OFFSET;
700 static ByteSize init_thread_offset() { return in_ByteSize(sizeof(klassOopDesc) + offset_of(instanceKlass, _init_thread)); }
702 // subclass/subinterface checks
703 bool implements_interface(klassOop k) const;
705 // Access to the implementor of an interface.
706 klassOop implementor() const
707 {
708 klassOop* k = (klassOop*)adr_implementor();
709 if (k == NULL) {
710 return NULL;
711 } else {
712 return *k;
713 }
714 }
716 void set_implementor(klassOop k) {
717 assert(is_interface(), "not interface");
718 oop* addr = adr_implementor();
719 oop_store_without_check(addr, k);
720 }
722 int nof_implementors() const {
723 klassOop k = implementor();
724 if (k == NULL) {
725 return 0;
726 } else if (k != this->as_klassOop()) {
727 return 1;
728 } else {
729 return 2;
730 }
731 }
733 void add_implementor(klassOop k); // k is a new class that implements this interface
734 void init_implementor(); // initialize
736 // link this class into the implementors list of every interface it implements
737 void process_interfaces(Thread *thread);
739 // virtual operations from Klass
740 bool is_leaf_class() const { return _subklass == NULL; }
741 objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS);
742 bool compute_is_subtype_of(klassOop k);
743 bool can_be_primary_super_slow() const;
744 klassOop java_super() const { return super(); }
745 int oop_size(oop obj) const { return size_helper(); }
746 int klass_oop_size() const { return object_size(); }
747 bool oop_is_instance_slow() const { return true; }
749 // Iterators
750 void do_local_static_fields(FieldClosure* cl);
751 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
752 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS);
754 void methods_do(void f(methodOop method));
755 void array_klasses_do(void f(klassOop k));
756 void with_array_klasses_do(void f(klassOop k));
757 bool super_types_do(SuperTypeClosure* blk);
759 // Casting from klassOop
760 static instanceKlass* cast(klassOop k) {
761 assert(k->is_klass(), "must be");
762 Klass* kp = k->klass_part();
763 assert(kp->null_vtbl() || kp->oop_is_instance_slow(), "cast to instanceKlass");
764 return (instanceKlass*) kp;
765 }
767 // Sizing (in words)
768 static int header_size() { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); }
770 int object_size() const
771 {
772 return object_size(align_object_offset(vtable_length()) +
773 align_object_offset(itable_length()) +
774 ((is_interface() || is_anonymous()) ?
775 align_object_offset(nonstatic_oop_map_size()) :
776 nonstatic_oop_map_size()) +
777 (is_interface() ? (int)sizeof(klassOop)/HeapWordSize : 0) +
778 (is_anonymous() ? (int)sizeof(klassOop)/HeapWordSize : 0));
779 }
780 static int vtable_start_offset() { return header_size(); }
781 static int vtable_length_offset() { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; }
782 static int object_size(int extra) { return align_object_size(header_size() + extra); }
784 intptr_t* start_of_vtable() const { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); }
785 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); }
786 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)as_klassOop(); }
788 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); }
790 address static_field_addr(int offset);
792 OopMapBlock* start_of_nonstatic_oop_maps() const {
793 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
794 }
796 oop* adr_implementor() const {
797 if (is_interface()) {
798 return (oop*)(start_of_nonstatic_oop_maps() +
799 nonstatic_oop_map_count());
800 } else {
801 return NULL;
802 }
803 };
805 oop* adr_host_klass() const {
806 if (is_anonymous()) {
807 oop* adr_impl = adr_implementor();
808 if (adr_impl != NULL) {
809 return adr_impl + 1;
810 } else {
811 return (oop*)(start_of_nonstatic_oop_maps() +
812 nonstatic_oop_map_count());
813 }
814 } else {
815 return NULL;
816 }
817 }
819 // Allocation profiling support
820 juint alloc_size() const { return _alloc_count * size_helper(); }
821 void set_alloc_size(juint n) {}
823 // Use this to return the size of an instance in heap words:
824 int size_helper() const {
825 return layout_helper_to_size_helper(layout_helper());
826 }
828 // This bit is initialized in classFileParser.cpp.
829 // It is false under any of the following conditions:
830 // - the class is abstract (including any interface)
831 // - the class has a finalizer (if !RegisterFinalizersAtInit)
832 // - the class size is larger than FastAllocateSizeLimit
833 // - the class is java/lang/Class, which cannot be allocated directly
834 bool can_be_fastpath_allocated() const {
835 return !layout_helper_needs_slow_path(layout_helper());
836 }
838 // Java vtable/itable
839 klassVtable* vtable() const; // return new klassVtable wrapper
840 inline methodOop method_at_vtable(int index);
841 klassItable* itable() const; // return new klassItable wrapper
842 methodOop method_at_itable(klassOop holder, int index, TRAPS);
844 // Garbage collection
845 void oop_follow_contents(oop obj);
846 int oop_adjust_pointers(oop obj);
847 bool object_is_parsable() const { return _init_state != unparsable_by_gc; }
848 // Value of _init_state must be zero (unparsable_by_gc) when klass field is set.
850 void follow_weak_klass_links(
851 BoolObjectClosure* is_alive, OopClosure* keep_alive);
852 void release_C_heap_structures();
854 // Parallel Scavenge and Parallel Old
855 PARALLEL_GC_DECLS
857 // Naming
858 const char* signature_name() const;
860 // Iterators
861 int oop_oop_iterate(oop obj, OopClosure* blk) {
862 return oop_oop_iterate_v(obj, blk);
863 }
865 int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
866 return oop_oop_iterate_v_m(obj, blk, mr);
867 }
869 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
870 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \
871 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \
872 MemRegion mr);
874 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
875 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
877 #ifndef SERIALGC
878 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
879 int oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
881 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
882 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
883 #endif // !SERIALGC
885 private:
886 // initialization state
887 #ifdef ASSERT
888 void set_init_state(ClassState state);
889 #else
890 void set_init_state(ClassState state) { _init_state = (u1)state; }
891 #endif
892 void set_rewritten() { _misc_flags |= _misc_rewritten; }
893 void set_init_thread(Thread *thread) { _init_thread = thread; }
895 u2 idnum_allocated_count() const { return _idnum_allocated_count; }
896 // The RedefineClasses() API can cause new method idnums to be needed
897 // which will cause the caches to grow. Safety requires different
898 // cache management logic if the caches can grow instead of just
899 // going from NULL to non-NULL.
900 bool idnum_can_increment() const { return has_been_redefined(); }
901 jmethodID* methods_jmethod_ids_acquire() const
902 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
903 void release_set_methods_jmethod_ids(jmethodID* jmeths)
904 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
906 int* methods_cached_itable_indices_acquire() const
907 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); }
908 void release_set_methods_cached_itable_indices(int* indices)
909 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
911 inline typeArrayOop get_method_annotations_from(int idnum, objArrayOop annos);
912 void set_annotations(objArrayOop md, objArrayOop* md_p) { oop_store_without_check((oop*)md_p, (oop)md); }
913 void set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p);
915 // Offsets for memory management
916 oop* adr_array_klasses() const { return (oop*)&this->_array_klasses;}
917 oop* adr_methods() const { return (oop*)&this->_methods;}
918 oop* adr_method_ordering() const { return (oop*)&this->_method_ordering;}
919 oop* adr_local_interfaces() const { return (oop*)&this->_local_interfaces;}
920 oop* adr_transitive_interfaces() const { return (oop*)&this->_transitive_interfaces;}
921 oop* adr_fields() const { return (oop*)&this->_fields;}
922 oop* adr_constants() const { return (oop*)&this->_constants;}
923 oop* adr_class_loader() const { return (oop*)&this->_class_loader;}
924 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
925 oop* adr_signers() const { return (oop*)&this->_signers;}
926 oop* adr_inner_classes() const { return (oop*)&this->_inner_classes;}
927 oop* adr_methods_jmethod_ids() const { return (oop*)&this->_methods_jmethod_ids;}
928 oop* adr_methods_cached_itable_indices() const { return (oop*)&this->_methods_cached_itable_indices;}
929 oop* adr_class_annotations() const { return (oop*)&this->_class_annotations;}
930 oop* adr_fields_annotations() const { return (oop*)&this->_fields_annotations;}
931 oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;}
932 oop* adr_methods_parameter_annotations() const { return (oop*)&this->_methods_parameter_annotations;}
933 oop* adr_methods_default_annotations() const { return (oop*)&this->_methods_default_annotations;}
935 // Static methods that are used to implement member methods where an exposed this pointer
936 // is needed due to possible GCs
937 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
938 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
939 static void initialize_impl (instanceKlassHandle this_oop, TRAPS);
940 static void eager_initialize_impl (instanceKlassHandle this_oop);
941 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS);
942 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS);
943 static klassOop array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
944 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS);
945 /* jni_id_for_impl for jfieldID only */
946 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset);
948 // Returns the array class for the n'th dimension
949 klassOop array_klass_impl(bool or_null, int n, TRAPS);
951 // Returns the array class with this class as element type
952 klassOop array_klass_impl(bool or_null, TRAPS);
954 public:
955 // sharing support
956 virtual void remove_unshareable_info();
957 virtual void shared_symbols_iterate(SymbolClosure* closure);
959 // jvm support
960 jint compute_modifier_flags(TRAPS) const;
962 public:
963 // JVMTI support
964 jint jvmti_class_status() const;
966 public:
967 // Printing
968 void oop_print_value_on(oop obj, outputStream* st);
969 #ifndef PRODUCT
970 void oop_print_on (oop obj, outputStream* st);
972 void print_dependent_nmethods(bool verbose = false);
973 bool is_dependent_nmethod(nmethod* nm);
974 #endif
976 // Verification
977 const char* internal_name() const;
978 void oop_verify_on(oop obj, outputStream* st);
979 };
981 inline methodOop instanceKlass::method_at_vtable(int index) {
982 #ifndef PRODUCT
983 assert(index >= 0, "valid vtable index");
984 if (DebugVtables) {
985 verify_vtable_index(index);
986 }
987 #endif
988 vtableEntry* ve = (vtableEntry*)start_of_vtable();
989 return ve[index].method();
990 }
992 inline typeArrayOop instanceKlass::get_method_annotations_from(int idnum, objArrayOop annos) {
993 if (annos == NULL || annos->length() <= idnum) {
994 return NULL;
995 }
996 return typeArrayOop(annos->obj_at(idnum));
997 }
999 // for adding methods
1000 // UNSET_IDNUM return means no more ids available
1001 inline u2 instanceKlass::next_method_idnum() {
1002 if (_idnum_allocated_count == constMethodOopDesc::MAX_IDNUM) {
1003 return constMethodOopDesc::UNSET_IDNUM; // no more ids available
1004 } else {
1005 return _idnum_allocated_count++;
1006 }
1007 }
1010 /* JNIid class for jfieldIDs only */
1011 class JNIid: public CHeapObj<mtClass> {
1012 friend class VMStructs;
1013 private:
1014 klassOop _holder;
1015 JNIid* _next;
1016 int _offset;
1017 #ifdef ASSERT
1018 bool _is_static_field_id;
1019 #endif
1021 public:
1022 // Accessors
1023 klassOop holder() const { return _holder; }
1024 int offset() const { return _offset; }
1025 JNIid* next() { return _next; }
1026 // Constructor
1027 JNIid(klassOop holder, int offset, JNIid* next);
1028 // Identifier lookup
1029 JNIid* find(int offset);
1031 bool find_local_field(fieldDescriptor* fd) {
1032 return instanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1033 }
1035 // Garbage collection support
1036 oop* holder_addr() { return (oop*)&_holder; }
1037 void oops_do(OopClosure* f);
1038 static void deallocate(JNIid* id);
1039 // Debugging
1040 #ifdef ASSERT
1041 bool is_static_field_id() const { return _is_static_field_id; }
1042 void set_is_static_field_id() { _is_static_field_id = true; }
1043 #endif
1044 void verify(klassOop holder);
1045 };
1048 // If breakpoints are more numerous than just JVMTI breakpoints,
1049 // consider compressing this data structure.
1050 // It is currently a simple linked list defined in methodOop.hpp.
1052 class BreakpointInfo;
1055 // A collection point for interesting information about the previous
1056 // version(s) of an instanceKlass. This class uses weak references to
1057 // the information so that the information may be collected as needed
1058 // by the system. If the information is shared, then a regular
1059 // reference must be used because a weak reference would be seen as
1060 // collectible. A GrowableArray of PreviousVersionNodes is attached
1061 // to the instanceKlass as needed. See PreviousVersionWalker below.
1062 class PreviousVersionNode : public CHeapObj<mtClass> {
1063 private:
1064 // A shared ConstantPool is never collected so we'll always have
1065 // a reference to it so we can update items in the cache. We'll
1066 // have a weak reference to a non-shared ConstantPool until all
1067 // of the methods (EMCP or obsolete) have been collected; the
1068 // non-shared ConstantPool becomes collectible at that point.
1069 jobject _prev_constant_pool; // regular or weak reference
1070 bool _prev_cp_is_weak; // true if not a shared ConstantPool
1072 // If the previous version of the instanceKlass doesn't have any
1073 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1074 // EMCP methods have been collected, then _prev_EMCP_methods can
1075 // have a length of zero.
1076 GrowableArray<jweak>* _prev_EMCP_methods;
1078 public:
1079 PreviousVersionNode(jobject prev_constant_pool, bool prev_cp_is_weak,
1080 GrowableArray<jweak>* prev_EMCP_methods);
1081 ~PreviousVersionNode();
1082 jobject prev_constant_pool() const {
1083 return _prev_constant_pool;
1084 }
1085 GrowableArray<jweak>* prev_EMCP_methods() const {
1086 return _prev_EMCP_methods;
1087 }
1088 };
1091 // A Handle-ized version of PreviousVersionNode.
1092 class PreviousVersionInfo : public ResourceObj {
1093 private:
1094 constantPoolHandle _prev_constant_pool_handle;
1095 // If the previous version of the instanceKlass doesn't have any
1096 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the
1097 // methods cannot be collected while we hold a handle,
1098 // _prev_EMCP_methods should never have a length of zero.
1099 GrowableArray<methodHandle>* _prev_EMCP_method_handles;
1101 public:
1102 PreviousVersionInfo(PreviousVersionNode *pv_node);
1103 ~PreviousVersionInfo();
1104 constantPoolHandle prev_constant_pool_handle() const {
1105 return _prev_constant_pool_handle;
1106 }
1107 GrowableArray<methodHandle>* prev_EMCP_method_handles() const {
1108 return _prev_EMCP_method_handles;
1109 }
1110 };
1113 // Helper object for walking previous versions. This helper cleans up
1114 // the Handles that it allocates when the helper object is destroyed.
1115 // The PreviousVersionInfo object returned by next_previous_version()
1116 // is only valid until a subsequent call to next_previous_version() or
1117 // the helper object is destroyed.
1118 class PreviousVersionWalker : public StackObj {
1119 private:
1120 GrowableArray<PreviousVersionNode *>* _previous_versions;
1121 int _current_index;
1122 // Fields for cleaning up when we are done walking the previous versions:
1123 // A HandleMark for the PreviousVersionInfo handles:
1124 HandleMark _hm;
1126 // It would be nice to have a ResourceMark field in this helper also,
1127 // but the ResourceMark code says to be careful to delete handles held
1128 // in GrowableArrays _before_ deleting the GrowableArray. Since we
1129 // can't guarantee the order in which the fields are destroyed, we
1130 // have to let the creator of the PreviousVersionWalker object do
1131 // the right thing. Also, adding a ResourceMark here causes an
1132 // include loop.
1134 // A pointer to the current info object so we can handle the deletes.
1135 PreviousVersionInfo * _current_p;
1137 public:
1138 PreviousVersionWalker(instanceKlass *ik);
1139 ~PreviousVersionWalker();
1141 // Return the interesting information for the next previous version
1142 // of the klass. Returns NULL if there are no more previous versions.
1143 PreviousVersionInfo* next_previous_version();
1144 };
1147 //
1148 // nmethodBucket is used to record dependent nmethods for
1149 // deoptimization. nmethod dependencies are actually <klass, method>
1150 // pairs but we really only care about the klass part for purposes of
1151 // finding nmethods which might need to be deoptimized. Instead of
1152 // recording the method, a count of how many times a particular nmethod
1153 // was recorded is kept. This ensures that any recording errors are
1154 // noticed since an nmethod should be removed as many times are it's
1155 // added.
1156 //
1157 class nmethodBucket: public CHeapObj<mtClass> {
1158 friend class VMStructs;
1159 private:
1160 nmethod* _nmethod;
1161 int _count;
1162 nmethodBucket* _next;
1164 public:
1165 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1166 _nmethod = nmethod;
1167 _next = next;
1168 _count = 1;
1169 }
1170 int count() { return _count; }
1171 int increment() { _count += 1; return _count; }
1172 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1173 nmethodBucket* next() { return _next; }
1174 void set_next(nmethodBucket* b) { _next = b; }
1175 nmethod* get_nmethod() { return _nmethod; }
1176 };
1178 // An iterator that's used to access the inner classes indices in the
1179 // instanceKlass::_inner_classes array.
1180 class InnerClassesIterator : public StackObj {
1181 private:
1182 typeArrayHandle _inner_classes;
1183 int _length;
1184 int _idx;
1185 public:
1187 InnerClassesIterator(instanceKlassHandle k) {
1188 _inner_classes = k->inner_classes();
1189 if (k->inner_classes() != NULL) {
1190 _length = _inner_classes->length();
1191 // The inner class array's length should be the multiple of
1192 // inner_class_next_offset if it only contains the InnerClasses
1193 // attribute data, or it should be
1194 // n*inner_class_next_offset+enclosing_method_attribute_size
1195 // if it also contains the EnclosingMethod data.
1196 assert((_length % instanceKlass::inner_class_next_offset == 0 ||
1197 _length % instanceKlass::inner_class_next_offset == instanceKlass::enclosing_method_attribute_size),
1198 "just checking");
1199 // Remove the enclosing_method portion if exists.
1200 if (_length % instanceKlass::inner_class_next_offset == instanceKlass::enclosing_method_attribute_size) {
1201 _length -= instanceKlass::enclosing_method_attribute_size;
1202 }
1203 } else {
1204 _length = 0;
1205 }
1206 _idx = 0;
1207 }
1209 int length() const {
1210 return _length;
1211 }
1213 void next() {
1214 _idx += instanceKlass::inner_class_next_offset;
1215 }
1217 bool done() const {
1218 return (_idx >= _length);
1219 }
1221 u2 inner_class_info_index() const {
1222 return _inner_classes->ushort_at(
1223 _idx + instanceKlass::inner_class_inner_class_info_offset);
1224 }
1226 void set_inner_class_info_index(u2 index) {
1227 _inner_classes->ushort_at_put(
1228 _idx + instanceKlass::inner_class_inner_class_info_offset, index);
1229 }
1231 u2 outer_class_info_index() const {
1232 return _inner_classes->ushort_at(
1233 _idx + instanceKlass::inner_class_outer_class_info_offset);
1234 }
1236 void set_outer_class_info_index(u2 index) {
1237 _inner_classes->ushort_at_put(
1238 _idx + instanceKlass::inner_class_outer_class_info_offset, index);
1239 }
1241 u2 inner_name_index() const {
1242 return _inner_classes->ushort_at(
1243 _idx + instanceKlass::inner_class_inner_name_offset);
1244 }
1246 void set_inner_name_index(u2 index) {
1247 _inner_classes->ushort_at_put(
1248 _idx + instanceKlass::inner_class_inner_name_offset, index);
1249 }
1251 u2 inner_access_flags() const {
1252 return _inner_classes->ushort_at(
1253 _idx + instanceKlass::inner_class_access_flags_offset);
1254 }
1255 };
1257 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP