Mercurial > hg > graal-jvmci-8
annotate src/share/vm/oops/instanceKlass.hpp @ 47:2c106685d6d0
6497639: 4/3 Profiling Swing application caused JVM crash
Summary: Make RedefineClasses() interoperate better with class sharing.
Reviewed-by: sspitsyn, jmasa
author | dcubed |
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date | Wed, 12 Mar 2008 18:06:50 -0700 |
parents | a61af66fc99e |
children | 31000d79ec71 |
rev | line source |
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0 | 1 /* |
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 // An instanceKlass is the VM level representation of a Java class. | |
26 // It contains all information needed for at class at execution runtime. | |
27 | |
28 // instanceKlass layout: | |
29 // [header ] klassOop | |
30 // [klass pointer ] klassOop | |
31 // [C++ vtbl pointer ] Klass | |
32 // [subtype cache ] Klass | |
33 // [instance size ] Klass | |
34 // [java mirror ] Klass | |
35 // [super ] Klass | |
36 // [access_flags ] Klass | |
37 // [name ] Klass | |
38 // [first subklass ] Klass | |
39 // [next sibling ] Klass | |
40 // [array klasses ] | |
41 // [methods ] | |
42 // [local interfaces ] | |
43 // [transitive interfaces ] | |
44 // [number of implementors ] | |
45 // [implementors ] klassOop[2] | |
46 // [fields ] | |
47 // [constants ] | |
48 // [class loader ] | |
49 // [protection domain ] | |
50 // [signers ] | |
51 // [source file name ] | |
52 // [inner classes ] | |
53 // [static field size ] | |
54 // [nonstatic field size ] | |
55 // [static oop fields size ] | |
56 // [nonstatic oop maps size ] | |
57 // [has finalize method ] | |
58 // [deoptimization mark bit ] | |
59 // [initialization state ] | |
60 // [initializing thread ] | |
61 // [Java vtable length ] | |
62 // [oop map cache (stack maps) ] | |
63 // [EMBEDDED Java vtable ] size in words = vtable_len | |
64 // [EMBEDDED static oop fields ] size in words = static_oop_fields_size | |
65 // [ static non-oop fields ] size in words = static_field_size - static_oop_fields_size | |
66 // [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size | |
67 // | |
68 // The embedded nonstatic oop-map blocks are short pairs (offset, length) indicating | |
69 // where oops are located in instances of this klass. | |
70 | |
71 | |
72 // forward declaration for class -- see below for definition | |
73 class SuperTypeClosure; | |
74 class OopMapBlock; | |
75 class JNIid; | |
76 class jniIdMapBase; | |
77 class BreakpointInfo; | |
78 class fieldDescriptor; | |
79 class DepChange; | |
80 class nmethodBucket; | |
81 class PreviousVersionNode; | |
82 class JvmtiCachedClassFieldMap; | |
83 | |
84 // This is used in iterators below. | |
85 class FieldClosure: public StackObj { | |
86 public: | |
87 virtual void do_field(fieldDescriptor* fd) = 0; | |
88 }; | |
89 | |
90 #ifndef PRODUCT | |
91 // Print fields. | |
92 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields. | |
93 class FieldPrinter: public FieldClosure { | |
94 oop _obj; | |
95 outputStream* _st; | |
96 public: | |
97 FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {} | |
98 void do_field(fieldDescriptor* fd); | |
99 }; | |
100 #endif // !PRODUCT | |
101 | |
102 class instanceKlass: public Klass { | |
103 friend class VMStructs; | |
104 public: | |
105 // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description | |
106 // of the class loading & initialization procedure, and the use of the states. | |
107 enum ClassState { | |
108 unparsable_by_gc = 0, // object is not yet parsable by gc. Value of _init_state at object allocation. | |
109 allocated, // allocated (but not yet linked) | |
110 loaded, // loaded and inserted in class hierarchy (but not linked yet) | |
111 linked, // successfully linked/verified (but not initialized yet) | |
112 being_initialized, // currently running class initializer | |
113 fully_initialized, // initialized (successfull final state) | |
114 initialization_error // error happened during initialization | |
115 }; | |
116 | |
117 public: | |
118 oop* oop_block_beg() const { return adr_array_klasses(); } | |
119 oop* oop_block_end() const { return adr_methods_default_annotations() + 1; } | |
120 | |
121 enum { | |
122 implementors_limit = 2 // how many implems can we track? | |
123 }; | |
124 | |
125 protected: | |
126 // | |
127 // The oop block. See comment in klass.hpp before making changes. | |
128 // | |
129 | |
130 // Array classes holding elements of this class. | |
131 klassOop _array_klasses; | |
132 // Method array. | |
133 objArrayOop _methods; | |
134 // Int array containing the original order of method in the class file (for | |
135 // JVMTI). | |
136 typeArrayOop _method_ordering; | |
137 // Interface (klassOops) this class declares locally to implement. | |
138 objArrayOop _local_interfaces; | |
139 // Interface (klassOops) this class implements transitively. | |
140 objArrayOop _transitive_interfaces; | |
141 // Instance and static variable information, 5-tuples of shorts [access, name | |
142 // index, sig index, initval index, offset]. | |
143 typeArrayOop _fields; | |
144 // Constant pool for this class. | |
145 constantPoolOop _constants; | |
146 // Class loader used to load this class, NULL if VM loader used. | |
147 oop _class_loader; | |
148 // Protection domain. | |
149 oop _protection_domain; | |
150 // Class signers. | |
151 objArrayOop _signers; | |
152 // Name of source file containing this klass, NULL if not specified. | |
153 symbolOop _source_file_name; | |
154 // the source debug extension for this klass, NULL if not specified. | |
155 symbolOop _source_debug_extension; | |
156 // inner_classes attribute. | |
157 typeArrayOop _inner_classes; | |
158 // Implementors of this interface (not valid if it overflows) | |
159 klassOop _implementors[implementors_limit]; | |
160 // Generic signature, or null if none. | |
161 symbolOop _generic_signature; | |
162 // Annotations for this class, or null if none. | |
163 typeArrayOop _class_annotations; | |
164 // Annotation objects (byte arrays) for fields, or null if no annotations. | |
165 // Indices correspond to entries (not indices) in fields array. | |
166 objArrayOop _fields_annotations; | |
167 // Annotation objects (byte arrays) for methods, or null if no annotations. | |
168 // Index is the idnum, which is initially the same as the methods array index. | |
169 objArrayOop _methods_annotations; | |
170 // Annotation objects (byte arrays) for methods' parameters, or null if no | |
171 // such annotations. | |
172 // Index is the idnum, which is initially the same as the methods array index. | |
173 objArrayOop _methods_parameter_annotations; | |
174 // Annotation objects (byte arrays) for methods' default values, or null if no | |
175 // such annotations. | |
176 // Index is the idnum, which is initially the same as the methods array index. | |
177 objArrayOop _methods_default_annotations; | |
178 | |
179 // | |
180 // End of the oop block. | |
181 // | |
182 | |
183 int _nonstatic_field_size; // number of non-static fields in this klass (including inherited fields) | |
184 int _static_field_size; // number of static fields (oop and non-oop) in this klass | |
185 int _static_oop_field_size;// number of static oop fields in this klass | |
186 int _nonstatic_oop_map_size;// number of nonstatic oop-map blocks allocated at end of this klass | |
187 bool _is_marked_dependent; // used for marking during flushing and deoptimization | |
188 bool _rewritten; // methods rewritten. | |
189 u2 _minor_version; // minor version number of class file | |
190 u2 _major_version; // major version number of class file | |
191 ClassState _init_state; // state of class | |
192 Thread* _init_thread; // Pointer to current thread doing initialization (to handle recusive initialization) | |
193 int _vtable_len; // length of Java vtable (in words) | |
194 int _itable_len; // length of Java itable (in words) | |
195 ReferenceType _reference_type; // reference type | |
196 OopMapCache* volatile _oop_map_cache; // OopMapCache for all methods in the klass (allocated lazily) | |
197 JNIid* _jni_ids; // First JNI identifier for static fields in this class | |
198 jmethodID* _methods_jmethod_ids; // jmethodIDs corresponding to method_idnum, or NULL if none | |
199 int* _methods_cached_itable_indices; // itable_index cache for JNI invoke corresponding to methods idnum, or NULL | |
200 nmethodBucket* _dependencies; // list of dependent nmethods | |
201 nmethod* _osr_nmethods_head; // Head of list of on-stack replacement nmethods for this class | |
202 BreakpointInfo* _breakpoints; // bpt lists, managed by methodOop | |
203 int _nof_implementors; // No of implementors of this interface (zero if not an interface) | |
204 // Array of interesting part(s) of the previous version(s) of this | |
205 // instanceKlass. See PreviousVersionWalker below. | |
206 GrowableArray<PreviousVersionNode *>* _previous_versions; | |
207 u2 _enclosing_method_class_index; // Constant pool index for class of enclosing method, or 0 if none | |
208 u2 _enclosing_method_method_index; // Constant pool index for name and type of enclosing method, or 0 if none | |
209 // JVMTI fields can be moved to their own structure - see 6315920 | |
210 unsigned char * _cached_class_file_bytes; // JVMTI: cached class file, before retransformable agent modified it in CFLH | |
211 jint _cached_class_file_len; // JVMTI: length of above | |
212 JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration | |
213 volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change | |
214 | |
215 // embedded Java vtable follows here | |
216 // embedded Java itables follows here | |
217 // embedded static fields follows here | |
218 // embedded nonstatic oop-map blocks follows here | |
219 | |
220 friend class instanceKlassKlass; | |
221 friend class SystemDictionary; | |
222 | |
223 public: | |
224 // field sizes | |
225 int nonstatic_field_size() const { return _nonstatic_field_size; } | |
226 void set_nonstatic_field_size(int size) { _nonstatic_field_size = size; } | |
227 | |
228 int static_field_size() const { return _static_field_size; } | |
229 void set_static_field_size(int size) { _static_field_size = size; } | |
230 | |
231 int static_oop_field_size() const { return _static_oop_field_size; } | |
232 void set_static_oop_field_size(int size) { _static_oop_field_size = size; } | |
233 | |
234 // Java vtable | |
235 int vtable_length() const { return _vtable_len; } | |
236 void set_vtable_length(int len) { _vtable_len = len; } | |
237 | |
238 // Java itable | |
239 int itable_length() const { return _itable_len; } | |
240 void set_itable_length(int len) { _itable_len = len; } | |
241 | |
242 // array klasses | |
243 klassOop array_klasses() const { return _array_klasses; } | |
244 void set_array_klasses(klassOop k) { oop_store_without_check((oop*) &_array_klasses, (oop) k); } | |
245 | |
246 // methods | |
247 objArrayOop methods() const { return _methods; } | |
248 void set_methods(objArrayOop a) { oop_store_without_check((oop*) &_methods, (oop) a); } | |
249 methodOop method_with_idnum(int idnum); | |
250 | |
251 // method ordering | |
252 typeArrayOop method_ordering() const { return _method_ordering; } | |
253 void set_method_ordering(typeArrayOop m) { oop_store_without_check((oop*) &_method_ordering, (oop) m); } | |
254 | |
255 // interfaces | |
256 objArrayOop local_interfaces() const { return _local_interfaces; } | |
257 void set_local_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_local_interfaces, (oop) a); } | |
258 objArrayOop transitive_interfaces() const { return _transitive_interfaces; } | |
259 void set_transitive_interfaces(objArrayOop a) { oop_store_without_check((oop*) &_transitive_interfaces, (oop) a); } | |
260 | |
261 // fields | |
262 // Field info extracted from the class file and stored | |
263 // as an array of 7 shorts | |
264 enum FieldOffset { | |
265 access_flags_offset = 0, | |
266 name_index_offset = 1, | |
267 signature_index_offset = 2, | |
268 initval_index_offset = 3, | |
269 low_offset = 4, | |
270 high_offset = 5, | |
271 generic_signature_offset = 6, | |
272 next_offset = 7 | |
273 }; | |
274 | |
275 typeArrayOop fields() const { return _fields; } | |
276 int offset_from_fields( int index ) const { | |
277 return build_int_from_shorts( fields()->ushort_at(index + low_offset), | |
278 fields()->ushort_at(index + high_offset) ); | |
279 } | |
280 | |
281 void set_fields(typeArrayOop f) { oop_store_without_check((oop*) &_fields, (oop) f); } | |
282 | |
283 // inner classes | |
284 typeArrayOop inner_classes() const { return _inner_classes; } | |
285 void set_inner_classes(typeArrayOop f) { oop_store_without_check((oop*) &_inner_classes, (oop) f); } | |
286 | |
287 enum InnerClassAttributeOffset { | |
288 // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814 | |
289 inner_class_inner_class_info_offset = 0, | |
290 inner_class_outer_class_info_offset = 1, | |
291 inner_class_inner_name_offset = 2, | |
292 inner_class_access_flags_offset = 3, | |
293 inner_class_next_offset = 4 | |
294 }; | |
295 | |
296 // package | |
297 bool is_same_class_package(klassOop class2); | |
298 bool is_same_class_package(oop classloader2, symbolOop classname2); | |
299 static bool is_same_class_package(oop class_loader1, symbolOop class_name1, oop class_loader2, symbolOop class_name2); | |
300 | |
301 // initialization state | |
302 bool is_loaded() const { return _init_state >= loaded; } | |
303 bool is_linked() const { return _init_state >= linked; } | |
304 bool is_initialized() const { return _init_state == fully_initialized; } | |
305 bool is_not_initialized() const { return _init_state < being_initialized; } | |
306 bool is_being_initialized() const { return _init_state == being_initialized; } | |
307 bool is_in_error_state() const { return _init_state == initialization_error; } | |
308 bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; } | |
309 int get_init_state() { return _init_state; } // Useful for debugging | |
310 bool is_rewritten() const { return _rewritten; } | |
311 | |
312 // marking | |
313 bool is_marked_dependent() const { return _is_marked_dependent; } | |
314 void set_is_marked_dependent(bool value) { _is_marked_dependent = value; } | |
315 | |
316 // initialization (virtuals from Klass) | |
317 bool should_be_initialized() const; // means that initialize should be called | |
318 void initialize(TRAPS); | |
319 void link_class(TRAPS); | |
320 bool link_class_or_fail(TRAPS); // returns false on failure | |
321 void unlink_class(); | |
322 void rewrite_class(TRAPS); | |
323 methodOop class_initializer(); | |
324 | |
325 // set the class to initialized if no static initializer is present | |
326 void eager_initialize(Thread *thread); | |
327 | |
328 // reference type | |
329 ReferenceType reference_type() const { return _reference_type; } | |
330 void set_reference_type(ReferenceType t) { _reference_type = t; } | |
331 | |
332 // find local field, returns true if found | |
333 bool find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; | |
334 // find field in direct superinterfaces, returns the interface in which the field is defined | |
335 klassOop find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; | |
336 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined | |
337 klassOop find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const; | |
338 // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined | |
339 klassOop find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const; | |
340 | |
341 // find a non-static or static field given its offset within the class. | |
342 bool contains_field_offset(int offset) { | |
343 return ((offset/wordSize) >= instanceOopDesc::header_size() && | |
344 (offset/wordSize)-instanceOopDesc::header_size() < nonstatic_field_size()); | |
345 } | |
346 | |
347 bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; | |
348 bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const; | |
349 | |
350 // find a local method (returns NULL if not found) | |
351 methodOop find_method(symbolOop name, symbolOop signature) const; | |
352 static methodOop find_method(objArrayOop methods, symbolOop name, symbolOop signature); | |
353 | |
354 // lookup operation (returns NULL if not found) | |
355 methodOop uncached_lookup_method(symbolOop name, symbolOop signature) const; | |
356 | |
357 // lookup a method in all the interfaces that this class implements | |
358 // (returns NULL if not found) | |
359 methodOop lookup_method_in_all_interfaces(symbolOop name, symbolOop signature) const; | |
360 | |
361 // constant pool | |
362 constantPoolOop constants() const { return _constants; } | |
363 void set_constants(constantPoolOop c) { oop_store_without_check((oop*) &_constants, (oop) c); } | |
364 | |
365 // class loader | |
366 oop class_loader() const { return _class_loader; } | |
367 void set_class_loader(oop l) { oop_store((oop*) &_class_loader, l); } | |
368 | |
369 // protection domain | |
370 oop protection_domain() { return _protection_domain; } | |
371 void set_protection_domain(oop pd) { oop_store((oop*) &_protection_domain, pd); } | |
372 | |
373 // signers | |
374 objArrayOop signers() const { return _signers; } | |
375 void set_signers(objArrayOop s) { oop_store((oop*) &_signers, oop(s)); } | |
376 | |
377 // source file name | |
378 symbolOop source_file_name() const { return _source_file_name; } | |
379 void set_source_file_name(symbolOop n) { oop_store_without_check((oop*) &_source_file_name, (oop) n); } | |
380 | |
381 // minor and major version numbers of class file | |
382 u2 minor_version() const { return _minor_version; } | |
383 void set_minor_version(u2 minor_version) { _minor_version = minor_version; } | |
384 u2 major_version() const { return _major_version; } | |
385 void set_major_version(u2 major_version) { _major_version = major_version; } | |
386 | |
387 // source debug extension | |
388 symbolOop source_debug_extension() const { return _source_debug_extension; } | |
389 void set_source_debug_extension(symbolOop n){ oop_store_without_check((oop*) &_source_debug_extension, (oop) n); } | |
390 | |
391 // nonstatic oop-map blocks | |
392 int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; } | |
393 void set_nonstatic_oop_map_size(int size) { _nonstatic_oop_map_size = size; } | |
394 | |
395 // RedefineClasses() support for previous versions: | |
396 void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods, | |
397 int emcp_method_count); | |
398 bool has_previous_version() const; | |
399 void init_previous_versions() { | |
400 _previous_versions = NULL; | |
401 } | |
402 GrowableArray<PreviousVersionNode *>* previous_versions() const { | |
403 return _previous_versions; | |
404 } | |
405 | |
406 // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation | |
407 void set_cached_class_file(unsigned char *class_file_bytes, | |
408 jint class_file_len) { _cached_class_file_len = class_file_len; | |
409 _cached_class_file_bytes = class_file_bytes; } | |
410 jint get_cached_class_file_len() { return _cached_class_file_len; } | |
411 unsigned char * get_cached_class_file_bytes() { return _cached_class_file_bytes; } | |
412 | |
413 // JVMTI: Support for caching of field indices, types, and offsets | |
414 void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) { | |
415 _jvmti_cached_class_field_map = descriptor; | |
416 } | |
417 JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const { | |
418 return _jvmti_cached_class_field_map; | |
419 } | |
420 | |
421 // for adding methods, constMethodOopDesc::UNSET_IDNUM means no more ids available | |
422 inline u2 next_method_idnum(); | |
423 void set_initial_method_idnum(u2 value) { _idnum_allocated_count = value; } | |
424 | |
425 // generics support | |
426 symbolOop generic_signature() const { return _generic_signature; } | |
427 void set_generic_signature(symbolOop sig) { oop_store_without_check((oop*)&_generic_signature, (oop)sig); } | |
428 u2 enclosing_method_class_index() const { return _enclosing_method_class_index; } | |
429 u2 enclosing_method_method_index() const { return _enclosing_method_method_index; } | |
430 void set_enclosing_method_indices(u2 class_index, | |
431 u2 method_index) { _enclosing_method_class_index = class_index; | |
432 _enclosing_method_method_index = method_index; } | |
433 | |
434 // jmethodID support | |
435 static jmethodID jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h); | |
436 jmethodID jmethod_id_or_null(methodOop method); | |
437 | |
438 // cached itable index support | |
439 void set_cached_itable_index(size_t idnum, int index); | |
440 int cached_itable_index(size_t idnum); | |
441 | |
442 // annotations support | |
443 typeArrayOop class_annotations() const { return _class_annotations; } | |
444 objArrayOop fields_annotations() const { return _fields_annotations; } | |
445 objArrayOop methods_annotations() const { return _methods_annotations; } | |
446 objArrayOop methods_parameter_annotations() const { return _methods_parameter_annotations; } | |
447 objArrayOop methods_default_annotations() const { return _methods_default_annotations; } | |
448 void set_class_annotations(typeArrayOop md) { oop_store_without_check((oop*)&_class_annotations, (oop)md); } | |
449 void set_fields_annotations(objArrayOop md) { set_annotations(md, &_fields_annotations); } | |
450 void set_methods_annotations(objArrayOop md) { set_annotations(md, &_methods_annotations); } | |
451 void set_methods_parameter_annotations(objArrayOop md) { set_annotations(md, &_methods_parameter_annotations); } | |
452 void set_methods_default_annotations(objArrayOop md) { set_annotations(md, &_methods_default_annotations); } | |
453 typeArrayOop get_method_annotations_of(int idnum) | |
454 { return get_method_annotations_from(idnum, _methods_annotations); } | |
455 typeArrayOop get_method_parameter_annotations_of(int idnum) | |
456 { return get_method_annotations_from(idnum, _methods_parameter_annotations); } | |
457 typeArrayOop get_method_default_annotations_of(int idnum) | |
458 { return get_method_annotations_from(idnum, _methods_default_annotations); } | |
459 void set_method_annotations_of(int idnum, typeArrayOop anno) | |
460 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } | |
461 void set_method_parameter_annotations_of(int idnum, typeArrayOop anno) | |
462 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } | |
463 void set_method_default_annotations_of(int idnum, typeArrayOop anno) | |
464 { set_methods_annotations_of(idnum, anno, &_methods_annotations); } | |
465 | |
466 // allocation | |
467 DEFINE_ALLOCATE_PERMANENT(instanceKlass); | |
468 instanceOop allocate_instance(TRAPS); | |
469 instanceOop allocate_permanent_instance(TRAPS); | |
470 | |
471 // additional member function to return a handle | |
472 instanceHandle allocate_instance_handle(TRAPS) { return instanceHandle(THREAD, allocate_instance(THREAD)); } | |
473 | |
474 objArrayOop allocate_objArray(int n, int length, TRAPS); | |
475 // Helper function | |
476 static instanceOop register_finalizer(instanceOop i, TRAPS); | |
477 | |
478 // Check whether reflection/jni/jvm code is allowed to instantiate this class; | |
479 // if not, throw either an Error or an Exception. | |
480 virtual void check_valid_for_instantiation(bool throwError, TRAPS); | |
481 | |
482 // initialization | |
483 void call_class_initializer(TRAPS); | |
484 void set_initialization_state_and_notify(ClassState state, TRAPS); | |
485 | |
486 // OopMapCache support | |
487 OopMapCache* oop_map_cache() { return _oop_map_cache; } | |
488 void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; } | |
489 void mask_for(methodHandle method, int bci, InterpreterOopMap* entry); | |
490 | |
491 // JNI identifier support (for static fields - for jni performance) | |
492 JNIid* jni_ids() { return _jni_ids; } | |
493 void set_jni_ids(JNIid* ids) { _jni_ids = ids; } | |
494 JNIid* jni_id_for(int offset); | |
495 | |
496 // maintenance of deoptimization dependencies | |
497 int mark_dependent_nmethods(DepChange& changes); | |
498 void add_dependent_nmethod(nmethod* nm); | |
499 void remove_dependent_nmethod(nmethod* nm); | |
500 | |
501 // On-stack replacement support | |
502 nmethod* osr_nmethods_head() const { return _osr_nmethods_head; }; | |
503 void set_osr_nmethods_head(nmethod* h) { _osr_nmethods_head = h; }; | |
504 void add_osr_nmethod(nmethod* n); | |
505 void remove_osr_nmethod(nmethod* n); | |
506 nmethod* lookup_osr_nmethod(const methodOop m, int bci) const; | |
507 | |
508 // Breakpoint support (see methods on methodOop for details) | |
509 BreakpointInfo* breakpoints() const { return _breakpoints; }; | |
510 void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; }; | |
511 | |
512 // support for stub routines | |
513 static int init_state_offset_in_bytes() { return offset_of(instanceKlass, _init_state); } | |
514 static int init_thread_offset_in_bytes() { return offset_of(instanceKlass, _init_thread); } | |
515 | |
516 // subclass/subinterface checks | |
517 bool implements_interface(klassOop k) const; | |
518 | |
519 // Access to implementors of an interface. We only store the count | |
520 // of implementors, and in case, there are only a few | |
521 // implementors, we store them in a short list. | |
522 // This accessor returns NULL if we walk off the end of the list. | |
523 klassOop implementor(int i) const { | |
524 return (i < implementors_limit)? _implementors[i]: (klassOop) NULL; | |
525 } | |
526 int nof_implementors() const { return _nof_implementors; } | |
527 void add_implementor(klassOop k); // k is a new class that implements this interface | |
528 void init_implementor(); // initialize | |
529 | |
530 // link this class into the implementors list of every interface it implements | |
531 void process_interfaces(Thread *thread); | |
532 | |
533 // virtual operations from Klass | |
534 bool is_leaf_class() const { return _subklass == NULL; } | |
535 objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS); | |
536 bool compute_is_subtype_of(klassOop k); | |
537 bool can_be_primary_super_slow() const; | |
538 klassOop java_super() const { return super(); } | |
539 int oop_size(oop obj) const { return size_helper(); } | |
540 int klass_oop_size() const { return object_size(); } | |
541 bool oop_is_instance_slow() const { return true; } | |
542 | |
543 // Iterators | |
544 void do_local_static_fields(FieldClosure* cl); | |
545 void do_nonstatic_fields(FieldClosure* cl); // including inherited fields | |
546 void do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS); | |
547 | |
548 void methods_do(void f(methodOop method)); | |
549 void array_klasses_do(void f(klassOop k)); | |
550 void with_array_klasses_do(void f(klassOop k)); | |
551 bool super_types_do(SuperTypeClosure* blk); | |
552 | |
553 // Casting from klassOop | |
554 static instanceKlass* cast(klassOop k) { | |
555 Klass* kp = k->klass_part(); | |
556 assert(kp->null_vtbl() || kp->oop_is_instance_slow(), "cast to instanceKlass"); | |
557 return (instanceKlass*) kp; | |
558 } | |
559 | |
560 // Sizing (in words) | |
561 static int header_size() { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); } | |
562 int object_size() const { return object_size(align_object_offset(vtable_length()) + align_object_offset(itable_length()) + static_field_size() + nonstatic_oop_map_size()); } | |
563 static int vtable_start_offset() { return header_size(); } | |
564 static int vtable_length_offset() { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; } | |
565 static int object_size(int extra) { return align_object_size(header_size() + extra); } | |
566 | |
567 intptr_t* start_of_vtable() const { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); } | |
568 intptr_t* start_of_itable() const { return start_of_vtable() + align_object_offset(vtable_length()); } | |
569 int itable_offset_in_words() const { return start_of_itable() - (intptr_t*)as_klassOop(); } | |
570 | |
571 oop* start_of_static_fields() const { return (oop*)(start_of_itable() + align_object_offset(itable_length())); } | |
572 intptr_t* end_of_itable() const { return start_of_itable() + itable_length(); } | |
573 oop* end_of_static_fields() const { return start_of_static_fields() + static_field_size(); } | |
574 int offset_of_static_fields() const { return (intptr_t)start_of_static_fields() - (intptr_t)as_klassOop(); } | |
575 | |
576 OopMapBlock* start_of_nonstatic_oop_maps() const { return (OopMapBlock*) (start_of_static_fields() + static_field_size()); } | |
577 | |
578 // Allocation profiling support | |
579 juint alloc_size() const { return _alloc_count * size_helper(); } | |
580 void set_alloc_size(juint n) {} | |
581 | |
582 // Use this to return the size of an instance in heap words: | |
583 int size_helper() const { | |
584 return layout_helper_to_size_helper(layout_helper()); | |
585 } | |
586 | |
587 // This bit is initialized in classFileParser.cpp. | |
588 // It is false under any of the following conditions: | |
589 // - the class is abstract (including any interface) | |
590 // - the class has a finalizer (if !RegisterFinalizersAtInit) | |
591 // - the class size is larger than FastAllocateSizeLimit | |
592 // - the class is java/lang/Class, which cannot be allocated directly | |
593 bool can_be_fastpath_allocated() const { | |
594 return !layout_helper_needs_slow_path(layout_helper()); | |
595 } | |
596 | |
597 // Java vtable/itable | |
598 klassVtable* vtable() const; // return new klassVtable wrapper | |
599 inline methodOop method_at_vtable(int index); | |
600 klassItable* itable() const; // return new klassItable wrapper | |
601 methodOop method_at_itable(klassOop holder, int index, TRAPS); | |
602 | |
603 // Garbage collection | |
604 void oop_follow_contents(oop obj); | |
605 void follow_static_fields(); | |
606 void adjust_static_fields(); | |
607 int oop_adjust_pointers(oop obj); | |
608 bool object_is_parsable() const { return _init_state != unparsable_by_gc; } | |
609 // Value of _init_state must be zero (unparsable_by_gc) when klass field is set. | |
610 | |
611 void follow_weak_klass_links( | |
612 BoolObjectClosure* is_alive, OopClosure* keep_alive); | |
613 void release_C_heap_structures(); | |
614 | |
615 // Parallel Scavenge and Parallel Old | |
616 PARALLEL_GC_DECLS | |
617 | |
618 #ifndef SERIALGC | |
619 // Parallel Scavenge | |
620 void copy_static_fields(PSPromotionManager* pm); | |
621 void push_static_fields(PSPromotionManager* pm); | |
622 | |
623 // Parallel Old | |
624 void follow_static_fields(ParCompactionManager* cm); | |
625 void copy_static_fields(ParCompactionManager* cm); | |
626 void update_static_fields(); | |
627 void update_static_fields(HeapWord* beg_addr, HeapWord* end_addr); | |
628 #endif // SERIALGC | |
629 | |
630 // Naming | |
631 char* signature_name() const; | |
632 | |
633 // Iterators | |
634 int oop_oop_iterate(oop obj, OopClosure* blk) { | |
635 return oop_oop_iterate_v(obj, blk); | |
636 } | |
637 | |
638 int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) { | |
639 return oop_oop_iterate_v_m(obj, blk, mr); | |
640 } | |
641 | |
642 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \ | |
643 int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk); \ | |
644 int oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk, \ | |
645 MemRegion mr); | |
646 | |
647 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL) | |
648 ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DECL) | |
649 | |
650 void iterate_static_fields(OopClosure* closure); | |
651 void iterate_static_fields(OopClosure* closure, MemRegion mr); | |
652 | |
653 private: | |
654 // initialization state | |
655 #ifdef ASSERT | |
656 void set_init_state(ClassState state); | |
657 #else | |
658 void set_init_state(ClassState state) { _init_state = state; } | |
659 #endif | |
660 void set_rewritten() { _rewritten = true; } | |
661 void set_init_thread(Thread *thread) { _init_thread = thread; } | |
662 | |
663 u2 idnum_allocated_count() const { return _idnum_allocated_count; } | |
664 jmethodID* methods_jmethod_ids_acquire() const | |
665 { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); } | |
666 void release_set_methods_jmethod_ids(jmethodID* jmeths) | |
667 { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); } | |
668 | |
669 int* methods_cached_itable_indices_acquire() const | |
670 { return (int*)OrderAccess::load_ptr_acquire(&_methods_cached_itable_indices); } | |
671 void release_set_methods_cached_itable_indices(int* indices) | |
672 { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); } | |
673 | |
674 inline typeArrayOop get_method_annotations_from(int idnum, objArrayOop annos); | |
675 void set_annotations(objArrayOop md, objArrayOop* md_p) { oop_store_without_check((oop*)md_p, (oop)md); } | |
676 void set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p); | |
677 | |
678 // Offsets for memory management | |
679 oop* adr_array_klasses() const { return (oop*)&this->_array_klasses;} | |
680 oop* adr_methods() const { return (oop*)&this->_methods;} | |
681 oop* adr_method_ordering() const { return (oop*)&this->_method_ordering;} | |
682 oop* adr_local_interfaces() const { return (oop*)&this->_local_interfaces;} | |
683 oop* adr_transitive_interfaces() const { return (oop*)&this->_transitive_interfaces;} | |
684 oop* adr_fields() const { return (oop*)&this->_fields;} | |
685 oop* adr_constants() const { return (oop*)&this->_constants;} | |
686 oop* adr_class_loader() const { return (oop*)&this->_class_loader;} | |
687 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;} | |
688 oop* adr_signers() const { return (oop*)&this->_signers;} | |
689 oop* adr_source_file_name() const { return (oop*)&this->_source_file_name;} | |
690 oop* adr_source_debug_extension() const { return (oop*)&this->_source_debug_extension;} | |
691 oop* adr_inner_classes() const { return (oop*)&this->_inner_classes;} | |
692 oop* adr_implementors() const { return (oop*)&this->_implementors[0];} | |
693 oop* adr_generic_signature() const { return (oop*)&this->_generic_signature;} | |
694 oop* adr_methods_jmethod_ids() const { return (oop*)&this->_methods_jmethod_ids;} | |
695 oop* adr_methods_cached_itable_indices() const { return (oop*)&this->_methods_cached_itable_indices;} | |
696 oop* adr_class_annotations() const { return (oop*)&this->_class_annotations;} | |
697 oop* adr_fields_annotations() const { return (oop*)&this->_fields_annotations;} | |
698 oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;} | |
699 oop* adr_methods_parameter_annotations() const { return (oop*)&this->_methods_parameter_annotations;} | |
700 oop* adr_methods_default_annotations() const { return (oop*)&this->_methods_default_annotations;} | |
701 | |
702 // Static methods that are used to implement member methods where an exposed this pointer | |
703 // is needed due to possible GCs | |
704 static bool link_class_impl (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); | |
705 static bool verify_code (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS); | |
706 static void initialize_impl (instanceKlassHandle this_oop, TRAPS); | |
707 static void eager_initialize_impl (instanceKlassHandle this_oop); | |
708 static void set_initialization_state_and_notify_impl (instanceKlassHandle this_oop, ClassState state, TRAPS); | |
709 static void call_class_initializer_impl (instanceKlassHandle this_oop, TRAPS); | |
710 static klassOop array_klass_impl (instanceKlassHandle this_oop, bool or_null, int n, TRAPS); | |
711 static void do_local_static_fields_impl (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS); | |
712 /* jni_id_for_impl for jfieldID only */ | |
713 static JNIid* jni_id_for_impl (instanceKlassHandle this_oop, int offset); | |
714 | |
715 // Returns the array class for the n'th dimension | |
716 klassOop array_klass_impl(bool or_null, int n, TRAPS); | |
717 | |
718 // Returns the array class with this class as element type | |
719 klassOop array_klass_impl(bool or_null, TRAPS); | |
720 | |
721 public: | |
722 // sharing support | |
723 virtual void remove_unshareable_info(); | |
724 void field_names_and_sigs_iterate(OopClosure* closure); | |
725 | |
726 // jvm support | |
727 jint compute_modifier_flags(TRAPS) const; | |
728 | |
729 public: | |
730 // JVMTI support | |
731 jint jvmti_class_status() const; | |
732 | |
733 #ifndef PRODUCT | |
734 public: | |
735 // Printing | |
736 void oop_print_on (oop obj, outputStream* st); | |
737 void oop_print_value_on(oop obj, outputStream* st); | |
738 | |
739 void print_dependent_nmethods(bool verbose = false); | |
740 bool is_dependent_nmethod(nmethod* nm); | |
741 #endif | |
742 | |
743 public: | |
744 // Verification | |
745 const char* internal_name() const; | |
746 void oop_verify_on(oop obj, outputStream* st); | |
747 | |
748 #ifndef PRODUCT | |
749 static void verify_class_klass_nonstatic_oop_maps(klassOop k) PRODUCT_RETURN; | |
750 #endif | |
751 }; | |
752 | |
753 inline methodOop instanceKlass::method_at_vtable(int index) { | |
754 #ifndef PRODUCT | |
755 assert(index >= 0, "valid vtable index"); | |
756 if (DebugVtables) { | |
757 verify_vtable_index(index); | |
758 } | |
759 #endif | |
760 vtableEntry* ve = (vtableEntry*)start_of_vtable(); | |
761 return ve[index].method(); | |
762 } | |
763 | |
764 inline typeArrayOop instanceKlass::get_method_annotations_from(int idnum, objArrayOop annos) { | |
765 if (annos == NULL || annos->length() <= idnum) { | |
766 return NULL; | |
767 } | |
768 return typeArrayOop(annos->obj_at(idnum)); | |
769 } | |
770 | |
771 // for adding methods | |
772 // UNSET_IDNUM return means no more ids available | |
773 inline u2 instanceKlass::next_method_idnum() { | |
774 if (_idnum_allocated_count == constMethodOopDesc::MAX_IDNUM) { | |
775 return constMethodOopDesc::UNSET_IDNUM; // no more ids available | |
776 } else { | |
777 return _idnum_allocated_count++; | |
778 } | |
779 } | |
780 | |
781 | |
782 // ValueObjs embedded in klass. Describes where oops are located in instances of this klass. | |
783 | |
784 class OopMapBlock VALUE_OBJ_CLASS_SPEC { | |
785 private: | |
786 jushort _offset; // Offset of first oop in oop-map block | |
787 jushort _length; // Length of oop-map block | |
788 public: | |
789 // Accessors | |
790 jushort offset() const { return _offset; } | |
791 void set_offset(jushort offset) { _offset = offset; } | |
792 | |
793 jushort length() const { return _length; } | |
794 void set_length(jushort length) { _length = length; } | |
795 }; | |
796 | |
797 /* JNIid class for jfieldIDs only */ | |
798 class JNIid: public CHeapObj { | |
799 friend class VMStructs; | |
800 private: | |
801 klassOop _holder; | |
802 JNIid* _next; | |
803 int _offset; | |
804 #ifdef ASSERT | |
805 bool _is_static_field_id; | |
806 #endif | |
807 | |
808 public: | |
809 // Accessors | |
810 klassOop holder() const { return _holder; } | |
811 int offset() const { return _offset; } | |
812 JNIid* next() { return _next; } | |
813 // Constructor | |
814 JNIid(klassOop holder, int offset, JNIid* next); | |
815 // Identifier lookup | |
816 JNIid* find(int offset); | |
817 | |
818 // Garbage collection support | |
819 oop* holder_addr() { return (oop*)&_holder; } | |
820 void oops_do(OopClosure* f); | |
821 static void deallocate(JNIid* id); | |
822 // Debugging | |
823 #ifdef ASSERT | |
824 bool is_static_field_id() const { return _is_static_field_id; } | |
825 void set_is_static_field_id() { _is_static_field_id = true; } | |
826 #endif | |
827 void verify(klassOop holder); | |
828 }; | |
829 | |
830 | |
831 // If breakpoints are more numerous than just JVMTI breakpoints, | |
832 // consider compressing this data structure. | |
833 // It is currently a simple linked list defined in methodOop.hpp. | |
834 | |
835 class BreakpointInfo; | |
836 | |
837 | |
838 // A collection point for interesting information about the previous | |
839 // version(s) of an instanceKlass. This class uses weak references to | |
840 // the information so that the information may be collected as needed | |
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841 // by the system. If the information is shared, then a regular |
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842 // reference must be used because a weak reference would be seen as |
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843 // collectible. A GrowableArray of PreviousVersionNodes is attached |
0 | 844 // to the instanceKlass as needed. See PreviousVersionWalker below. |
845 class PreviousVersionNode : public CHeapObj { | |
846 private: | |
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847 // A shared ConstantPool is never collected so we'll always have |
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848 // a reference to it so we can update items in the cache. We'll |
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849 // have a weak reference to a non-shared ConstantPool until all |
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850 // of the methods (EMCP or obsolete) have been collected; the |
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851 // non-shared ConstantPool becomes collectible at that point. |
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852 jobject _prev_constant_pool; // regular or weak reference |
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853 bool _prev_cp_is_weak; // true if not a shared ConstantPool |
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854 |
0 | 855 // If the previous version of the instanceKlass doesn't have any |
856 // EMCP methods, then _prev_EMCP_methods will be NULL. If all the | |
857 // EMCP methods have been collected, then _prev_EMCP_methods can | |
858 // have a length of zero. | |
859 GrowableArray<jweak>* _prev_EMCP_methods; | |
860 | |
861 public: | |
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862 PreviousVersionNode(jobject prev_constant_pool, bool prev_cp_is_weak, |
0 | 863 GrowableArray<jweak>* prev_EMCP_methods); |
864 ~PreviousVersionNode(); | |
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865 jobject prev_constant_pool() const { |
0 | 866 return _prev_constant_pool; |
867 } | |
868 GrowableArray<jweak>* prev_EMCP_methods() const { | |
869 return _prev_EMCP_methods; | |
870 } | |
871 }; | |
872 | |
873 | |
874 // A Handle-ized version of PreviousVersionNode. | |
875 class PreviousVersionInfo : public ResourceObj { | |
876 private: | |
877 constantPoolHandle _prev_constant_pool_handle; | |
878 // If the previous version of the instanceKlass doesn't have any | |
879 // EMCP methods, then _prev_EMCP_methods will be NULL. Since the | |
880 // methods cannot be collected while we hold a handle, | |
881 // _prev_EMCP_methods should never have a length of zero. | |
882 GrowableArray<methodHandle>* _prev_EMCP_method_handles; | |
883 | |
884 public: | |
885 PreviousVersionInfo(PreviousVersionNode *pv_node); | |
886 ~PreviousVersionInfo(); | |
887 constantPoolHandle prev_constant_pool_handle() const { | |
888 return _prev_constant_pool_handle; | |
889 } | |
890 GrowableArray<methodHandle>* prev_EMCP_method_handles() const { | |
891 return _prev_EMCP_method_handles; | |
892 } | |
893 }; | |
894 | |
895 | |
896 // Helper object for walking previous versions. This helper cleans up | |
897 // the Handles that it allocates when the helper object is destroyed. | |
898 // The PreviousVersionInfo object returned by next_previous_version() | |
899 // is only valid until a subsequent call to next_previous_version() or | |
900 // the helper object is destroyed. | |
901 class PreviousVersionWalker : public StackObj { | |
902 private: | |
903 GrowableArray<PreviousVersionNode *>* _previous_versions; | |
904 int _current_index; | |
905 // Fields for cleaning up when we are done walking the previous versions: | |
906 // A HandleMark for the PreviousVersionInfo handles: | |
907 HandleMark _hm; | |
908 | |
909 // It would be nice to have a ResourceMark field in this helper also, | |
910 // but the ResourceMark code says to be careful to delete handles held | |
911 // in GrowableArrays _before_ deleting the GrowableArray. Since we | |
912 // can't guarantee the order in which the fields are destroyed, we | |
913 // have to let the creator of the PreviousVersionWalker object do | |
914 // the right thing. Also, adding a ResourceMark here causes an | |
915 // include loop. | |
916 | |
917 // A pointer to the current info object so we can handle the deletes. | |
918 PreviousVersionInfo * _current_p; | |
919 | |
920 public: | |
921 PreviousVersionWalker(instanceKlass *ik); | |
922 ~PreviousVersionWalker(); | |
923 | |
924 // Return the interesting information for the next previous version | |
925 // of the klass. Returns NULL if there are no more previous versions. | |
926 PreviousVersionInfo* next_previous_version(); | |
927 }; |