1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/heapInspection.hpp"
38 #include "memory/metadataFactory.hpp"
39 #include "memory/oopFactory.hpp"
40 #include "oops/fieldStreams.hpp"
41 #include "oops/instanceClassLoaderKlass.hpp"
42 #include "oops/instanceKlass.hpp"
43 #include "oops/instanceMirrorKlass.hpp"
44 #include "oops/instanceOop.hpp"
45 #include "oops/klass.inline.hpp"
46 #include "oops/method.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/symbol.hpp"
49 #include "prims/jvmtiExport.hpp"
50 #include "prims/jvmtiRedefineClassesTrace.hpp"
51 #include "prims/jvmtiRedefineClasses.hpp"
52 #include "prims/methodComparator.hpp"
53 #include "runtime/fieldDescriptor.hpp"
54 #include "runtime/handles.inline.hpp"
55 #include "runtime/javaCalls.hpp"
56 #include "runtime/mutexLocker.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "services/classLoadingService.hpp"
59 #include "services/threadService.hpp"
60 #include "utilities/dtrace.hpp"
61 #include "utilities/macros.hpp"
62 #if INCLUDE_ALL_GCS
63 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
64 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
65 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
66 #include "gc_implementation/g1/g1RemSet.inline.hpp"
67 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
68 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
69 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
70 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
71 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
72 #include "oops/oop.pcgc.inline.hpp"
73 #endif // INCLUDE_ALL_GCS
74 #ifdef COMPILER1
75 #include "c1/c1_Compiler.hpp"
76 #endif
77
78 #ifdef DTRACE_ENABLED
79
80 #ifndef USDT2
81
82 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
83 char*, intptr_t, oop, intptr_t);
84 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
85 char*, intptr_t, oop, intptr_t, int);
86 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
87 char*, intptr_t, oop, intptr_t, int);
88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
89 char*, intptr_t, oop, intptr_t, int);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
95 char*, intptr_t, oop, intptr_t, int);
96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
97 char*, intptr_t, oop, intptr_t, int);
98
99 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
100 { \
101 char* data = NULL; \
102 int len = 0; \
103 Symbol* name = (clss)->name(); \
104 if (name != NULL) { \
105 data = (char*)name->bytes(); \
106 len = name->utf8_length(); \
107 } \
108 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
109 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type); \
110 }
111
112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
113 { \
114 char* data = NULL; \
115 int len = 0; \
116 Symbol* name = (clss)->name(); \
117 if (name != NULL) { \
118 data = (char*)name->bytes(); \
119 len = name->utf8_length(); \
120 } \
121 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
122 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type, wait); \
123 }
124 #else /* USDT2 */
125
126 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
127 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
128 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
129 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
130 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
131 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
132 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
133 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
134 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
135 { \
136 char* data = NULL; \
137 int len = 0; \
138 Symbol* name = (clss)->name(); \
139 if (name != NULL) { \
140 data = (char*)name->bytes(); \
141 len = name->utf8_length(); \
142 } \
143 HOTSPOT_CLASS_INITIALIZATION_##type( \
144 data, len, (clss)->class_loader(), thread_type); \
145 }
146
147 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
148 { \
149 char* data = NULL; \
150 int len = 0; \
151 Symbol* name = (clss)->name(); \
152 if (name != NULL) { \
153 data = (char*)name->bytes(); \
154 len = name->utf8_length(); \
155 } \
156 HOTSPOT_CLASS_INITIALIZATION_##type( \
157 data, len, (clss)->class_loader(), thread_type, wait); \
158 }
159 #endif /* USDT2 */
160
161 #else // ndef DTRACE_ENABLED
162
163 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
164 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
165
166 #endif // ndef DTRACE_ENABLED
167
168 volatile int InstanceKlass::_total_instanceKlass_count = 0;
169
170 InstanceKlass* InstanceKlass::allocate_instance_klass(
171 ClassLoaderData* loader_data,
172 int vtable_len,
173 int itable_len,
174 int static_field_size,
175 int nonstatic_oop_map_size,
176 ReferenceType rt,
177 AccessFlags access_flags,
178 Symbol* name,
179 Klass* super_klass,
180 bool is_anonymous,
181 TRAPS) {
182
183 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
184 access_flags.is_interface(), is_anonymous);
185
186 // Allocation
187 InstanceKlass* ik;
188 if (rt == REF_NONE) {
189 if (name == vmSymbols::java_lang_Class()) {
190 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
191 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
192 access_flags, is_anonymous);
193 } else if (name == vmSymbols::java_lang_ClassLoader() ||
194 (SystemDictionary::ClassLoader_klass_loaded() &&
195 super_klass != NULL &&
196 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
197 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
198 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
199 access_flags, is_anonymous);
200 } else {
201 // normal class
202 ik = new (loader_data, size, THREAD) InstanceKlass(
203 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
204 access_flags, is_anonymous);
205 }
206 } else {
207 // reference klass
208 ik = new (loader_data, size, THREAD) InstanceRefKlass(
209 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
210 access_flags, is_anonymous);
211 }
212
213 // Check for pending exception before adding to the loader data and incrementing
214 // class count. Can get OOM here.
215 if (HAS_PENDING_EXCEPTION) {
216 return NULL;
217 }
218
219 // Add all classes to our internal class loader list here,
220 // including classes in the bootstrap (NULL) class loader.
221 loader_data->add_class(ik);
222
223 Atomic::inc(&_total_instanceKlass_count);
224 return ik;
225 }
226
227
228 // copy method ordering from resource area to Metaspace
229 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
230 if (m != NULL) {
231 // allocate a new array and copy contents (memcpy?)
232 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
233 for (int i = 0; i < m->length(); i++) {
234 _method_ordering->at_put(i, m->at(i));
235 }
236 } else {
237 _method_ordering = Universe::the_empty_int_array();
238 }
239 }
240
241 // create a new array of vtable_indices for default methods
242 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
243 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
244 assert(default_vtable_indices() == NULL, "only create once");
245 set_default_vtable_indices(vtable_indices);
246 return vtable_indices;
247 }
248
249 InstanceKlass::InstanceKlass(int vtable_len,
250 int itable_len,
251 int static_field_size,
252 int nonstatic_oop_map_size,
253 ReferenceType rt,
254 AccessFlags access_flags,
255 bool is_anonymous) {
256 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
257
258 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
259 access_flags.is_interface(), is_anonymous);
260
261 set_vtable_length(vtable_len);
262 set_itable_length(itable_len);
263 set_static_field_size(static_field_size);
264 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
265 set_access_flags(access_flags);
266 _misc_flags = 0; // initialize to zero
267 set_is_anonymous(is_anonymous);
268 assert(size() == iksize, "wrong size for object");
269
270 set_array_klasses(NULL);
271 set_methods(NULL);
272 set_method_ordering(NULL);
273 set_default_methods(NULL);
274 set_default_vtable_indices(NULL);
275 set_local_interfaces(NULL);
276 set_transitive_interfaces(NULL);
277 init_implementor();
278 set_fields(NULL, 0);
279 set_constants(NULL);
280 set_class_loader_data(NULL);
281 set_source_file_name_index(0);
282 set_source_debug_extension(NULL, 0);
283 set_array_name(NULL);
284 set_inner_classes(NULL);
285 set_static_oop_field_count(0);
286 set_nonstatic_field_size(0);
287 set_is_marked_dependent(false);
288 set_init_state(InstanceKlass::allocated);
289 set_init_thread(NULL);
290 set_reference_type(rt);
291 set_oop_map_cache(NULL);
292 set_jni_ids(NULL);
293 set_osr_nmethods_head(NULL);
294 set_breakpoints(NULL);
295 init_previous_versions();
296 set_generic_signature_index(0);
297 release_set_methods_jmethod_ids(NULL);
298 set_annotations(NULL);
299 set_jvmti_cached_class_field_map(NULL);
300 set_initial_method_idnum(0);
301 _dependencies = NULL;
302 set_jvmti_cached_class_field_map(NULL);
303 set_cached_class_file(NULL);
304 set_initial_method_idnum(0);
305 set_minor_version(0);
306 set_major_version(0);
307 NOT_PRODUCT(_verify_count = 0;)
308
309 // initialize the non-header words to zero
310 intptr_t* p = (intptr_t*)this;
311 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
312 p[index] = NULL_WORD;
313 }
314
315 // Set temporary value until parseClassFile updates it with the real instance
316 // size.
317 set_layout_helper(Klass::instance_layout_helper(0, true));
318 }
319
320
321 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
322 Array<Method*>* methods) {
323 if (methods != NULL && methods != Universe::the_empty_method_array() &&
324 !methods->is_shared()) {
325 for (int i = 0; i < methods->length(); i++) {
326 Method* method = methods->at(i);
327 if (method == NULL) continue; // maybe null if error processing
328 // Only want to delete methods that are not executing for RedefineClasses.
329 // The previous version will point to them so they're not totally dangling
330 assert (!method->on_stack(), "shouldn't be called with methods on stack");
331 MetadataFactory::free_metadata(loader_data, method);
332 }
333 MetadataFactory::free_array<Method*>(loader_data, methods);
334 }
335 }
336
337 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
338 Klass* super_klass,
339 Array<Klass*>* local_interfaces,
340 Array<Klass*>* transitive_interfaces) {
341 // Only deallocate transitive interfaces if not empty, same as super class
342 // or same as local interfaces. See code in parseClassFile.
343 Array<Klass*>* ti = transitive_interfaces;
344 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
345 // check that the interfaces don't come from super class
346 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
347 InstanceKlass::cast(super_klass)->transitive_interfaces();
348 if (ti != sti && ti != NULL && !ti->is_shared()) {
349 MetadataFactory::free_array<Klass*>(loader_data, ti);
350 }
351 }
352
353 // local interfaces can be empty
354 if (local_interfaces != Universe::the_empty_klass_array() &&
355 local_interfaces != NULL && !local_interfaces->is_shared()) {
356 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
357 }
358 }
359
360 // This function deallocates the metadata and C heap pointers that the
361 // InstanceKlass points to.
362 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
363
364 // Orphan the mirror first, CMS thinks it's still live.
365 if (java_mirror() != NULL) {
366 java_lang_Class::set_klass(java_mirror(), NULL);
367 }
368
369 // Need to take this class off the class loader data list.
370 loader_data->remove_class(this);
371
372 // The array_klass for this class is created later, after error handling.
373 // For class redefinition, we keep the original class so this scratch class
374 // doesn't have an array class. Either way, assert that there is nothing
375 // to deallocate.
376 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
377
378 // Release C heap allocated data that this might point to, which includes
379 // reference counting symbol names.
380 release_C_heap_structures();
381
382 deallocate_methods(loader_data, methods());
383 set_methods(NULL);
384
385 if (method_ordering() != NULL &&
386 method_ordering() != Universe::the_empty_int_array() &&
387 !method_ordering()->is_shared()) {
388 MetadataFactory::free_array<int>(loader_data, method_ordering());
389 }
390 set_method_ordering(NULL);
391
392 // default methods can be empty
393 if (default_methods() != NULL &&
394 default_methods() != Universe::the_empty_method_array() &&
395 !default_methods()->is_shared()) {
396 MetadataFactory::free_array<Method*>(loader_data, default_methods());
397 }
398 // Do NOT deallocate the default methods, they are owned by superinterfaces.
399 set_default_methods(NULL);
400
401 // default methods vtable indices can be empty
402 if (default_vtable_indices() != NULL &&
403 !default_vtable_indices()->is_shared()) {
404 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
405 }
406 set_default_vtable_indices(NULL);
407
408
409 // This array is in Klass, but remove it with the InstanceKlass since
410 // this place would be the only caller and it can share memory with transitive
411 // interfaces.
412 if (secondary_supers() != NULL &&
413 secondary_supers() != Universe::the_empty_klass_array() &&
414 secondary_supers() != transitive_interfaces() &&
415 !secondary_supers()->is_shared()) {
416 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
417 }
418 set_secondary_supers(NULL);
419
420 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
421 set_transitive_interfaces(NULL);
422 set_local_interfaces(NULL);
423
424 if (fields() != NULL && !fields()->is_shared()) {
425 MetadataFactory::free_array<jushort>(loader_data, fields());
426 }
427 set_fields(NULL, 0);
428
429 // If a method from a redefined class is using this constant pool, don't
430 // delete it, yet. The new class's previous version will point to this.
431 if (constants() != NULL) {
432 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
433 if (!constants()->is_shared()) {
434 MetadataFactory::free_metadata(loader_data, constants());
435 }
436 set_constants(NULL);
437 }
438
439 if (inner_classes() != NULL &&
440 inner_classes() != Universe::the_empty_short_array() &&
441 !inner_classes()->is_shared()) {
442 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
443 }
444 set_inner_classes(NULL);
445
446 // We should deallocate the Annotations instance if it's not in shared spaces.
447 if (annotations() != NULL && !annotations()->is_shared()) {
448 MetadataFactory::free_metadata(loader_data, annotations());
449 }
450 set_annotations(NULL);
451 }
452
453 bool InstanceKlass::should_be_initialized() const {
454 return !is_initialized();
455 }
456
457 klassVtable* InstanceKlass::vtable() const {
458 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
459 }
460
461 klassItable* InstanceKlass::itable() const {
462 return new klassItable(instanceKlassHandle(this));
463 }
464
465 void InstanceKlass::eager_initialize(Thread *thread) {
466 if (!EagerInitialization) return;
467
468 if (this->is_not_initialized()) {
469 // abort if the the class has a class initializer
470 if (this->class_initializer() != NULL) return;
471
472 // abort if it is java.lang.Object (initialization is handled in genesis)
473 Klass* super = this->super();
474 if (super == NULL) return;
475
476 // abort if the super class should be initialized
477 if (!InstanceKlass::cast(super)->is_initialized()) return;
478
479 // call body to expose the this pointer
480 instanceKlassHandle this_oop(thread, this);
481 eager_initialize_impl(this_oop);
482 }
483 }
484
485 // JVMTI spec thinks there are signers and protection domain in the
486 // instanceKlass. These accessors pretend these fields are there.
487 // The hprof specification also thinks these fields are in InstanceKlass.
488 oop InstanceKlass::protection_domain() const {
489 // return the protection_domain from the mirror
490 return java_lang_Class::protection_domain(java_mirror());
491 }
492
493 // To remove these from requires an incompatible change and CCC request.
494 objArrayOop InstanceKlass::signers() const {
495 // return the signers from the mirror
496 return java_lang_Class::signers(java_mirror());
497 }
498
499 oop InstanceKlass::init_lock() const {
500 // return the init lock from the mirror
501 oop lock = java_lang_Class::init_lock(java_mirror());
502 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
503 "only fully initialized state can have a null lock");
504 return lock;
505 }
506
507 // Set the initialization lock to null so the object can be GC'ed. Any racing
508 // threads to get this lock will see a null lock and will not lock.
509 // That's okay because they all check for initialized state after getting
510 // the lock and return.
511 void InstanceKlass::fence_and_clear_init_lock() {
512 // make sure previous stores are all done, notably the init_state.
513 OrderAccess::storestore();
514 java_lang_Class::set_init_lock(java_mirror(), NULL);
515 assert(!is_not_initialized(), "class must be initialized now");
516 }
517
518 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
519 EXCEPTION_MARK;
520 oop init_lock = this_oop->init_lock();
521 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
522
523 // abort if someone beat us to the initialization
524 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
525
526 ClassState old_state = this_oop->init_state();
527 link_class_impl(this_oop, true, THREAD);
528 if (HAS_PENDING_EXCEPTION) {
529 CLEAR_PENDING_EXCEPTION;
530 // Abort if linking the class throws an exception.
531
532 // Use a test to avoid redundantly resetting the state if there's
533 // no change. Set_init_state() asserts that state changes make
534 // progress, whereas here we might just be spinning in place.
535 if( old_state != this_oop->_init_state )
536 this_oop->set_init_state (old_state);
537 } else {
538 // linking successfull, mark class as initialized
539 this_oop->set_init_state (fully_initialized);
540 this_oop->fence_and_clear_init_lock();
541 // trace
542 if (TraceClassInitialization) {
543 ResourceMark rm(THREAD);
544 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
545 }
546 }
547 }
548
549
550 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
551 // process. The step comments refers to the procedure described in that section.
552 // Note: implementation moved to static method to expose the this pointer.
553 void InstanceKlass::initialize(TRAPS) {
554 if (this->should_be_initialized()) {
555 HandleMark hm(THREAD);
556 instanceKlassHandle this_oop(THREAD, this);
557 initialize_impl(this_oop, CHECK);
558 // Note: at this point the class may be initialized
559 // OR it may be in the state of being initialized
560 // in case of recursive initialization!
561 } else {
562 assert(is_initialized(), "sanity check");
563 }
564 }
565
566
567 bool InstanceKlass::verify_code(
568 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
569 // 1) Verify the bytecodes
570 Verifier::Mode mode =
571 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
572 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
573 }
574
575
576 // Used exclusively by the shared spaces dump mechanism to prevent
577 // classes mapped into the shared regions in new VMs from appearing linked.
578
579 void InstanceKlass::unlink_class() {
580 assert(is_linked(), "must be linked");
581 _init_state = loaded;
582 }
583
584 void InstanceKlass::link_class(TRAPS) {
585 assert(is_loaded(), "must be loaded");
586 if (!is_linked()) {
587 HandleMark hm(THREAD);
588 instanceKlassHandle this_oop(THREAD, this);
589 link_class_impl(this_oop, true, CHECK);
590 }
591 }
592
593 // Called to verify that a class can link during initialization, without
594 // throwing a VerifyError.
595 bool InstanceKlass::link_class_or_fail(TRAPS) {
596 assert(is_loaded(), "must be loaded");
597 if (!is_linked()) {
598 HandleMark hm(THREAD);
599 instanceKlassHandle this_oop(THREAD, this);
600 link_class_impl(this_oop, false, CHECK_false);
601 }
602 return is_linked();
603 }
604
605 bool InstanceKlass::link_class_impl(
606 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
607 // check for error state
608 if (this_oop->is_in_error_state()) {
609 ResourceMark rm(THREAD);
610 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
611 this_oop->external_name(), false);
612 }
613 // return if already verified
614 if (this_oop->is_linked()) {
615 return true;
616 }
617
618 // Timing
619 // timer handles recursion
620 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
621 JavaThread* jt = (JavaThread*)THREAD;
622
623 // link super class before linking this class
624 instanceKlassHandle super(THREAD, this_oop->super());
625 if (super.not_null()) {
626 if (super->is_interface()) { // check if super class is an interface
627 ResourceMark rm(THREAD);
628 Exceptions::fthrow(
629 THREAD_AND_LOCATION,
630 vmSymbols::java_lang_IncompatibleClassChangeError(),
631 "class %s has interface %s as super class",
632 this_oop->external_name(),
633 super->external_name()
634 );
635 return false;
636 }
637
638 link_class_impl(super, throw_verifyerror, CHECK_false);
639 }
640
641 // link all interfaces implemented by this class before linking this class
642 Array<Klass*>* interfaces = this_oop->local_interfaces();
643 int num_interfaces = interfaces->length();
644 for (int index = 0; index < num_interfaces; index++) {
645 HandleMark hm(THREAD);
646 instanceKlassHandle ih(THREAD, interfaces->at(index));
647 link_class_impl(ih, throw_verifyerror, CHECK_false);
648 }
649
650 // in case the class is linked in the process of linking its superclasses
651 if (this_oop->is_linked()) {
652 return true;
653 }
654
655 // trace only the link time for this klass that includes
656 // the verification time
657 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
658 ClassLoader::perf_class_link_selftime(),
659 ClassLoader::perf_classes_linked(),
660 jt->get_thread_stat()->perf_recursion_counts_addr(),
661 jt->get_thread_stat()->perf_timers_addr(),
662 PerfClassTraceTime::CLASS_LINK);
663
664 // verification & rewriting
665 {
666 oop init_lock = this_oop->init_lock();
667 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
668 // rewritten will have been set if loader constraint error found
669 // on an earlier link attempt
670 // don't verify or rewrite if already rewritten
671
672 if (!this_oop->is_linked()) {
673 if (!this_oop->is_rewritten()) {
674 {
675 // Timer includes any side effects of class verification (resolution,
676 // etc), but not recursive entry into verify_code().
677 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
678 ClassLoader::perf_class_verify_selftime(),
679 ClassLoader::perf_classes_verified(),
680 jt->get_thread_stat()->perf_recursion_counts_addr(),
681 jt->get_thread_stat()->perf_timers_addr(),
682 PerfClassTraceTime::CLASS_VERIFY);
683 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
684 if (!verify_ok) {
685 return false;
686 }
687 }
688
689 // Just in case a side-effect of verify linked this class already
690 // (which can sometimes happen since the verifier loads classes
691 // using custom class loaders, which are free to initialize things)
692 if (this_oop->is_linked()) {
693 return true;
694 }
695
696 // also sets rewritten
697 this_oop->rewrite_class(CHECK_false);
698 }
699
700 // relocate jsrs and link methods after they are all rewritten
701 this_oop->link_methods(CHECK_false);
702
703 // Initialize the vtable and interface table after
704 // methods have been rewritten since rewrite may
705 // fabricate new Method*s.
706 // also does loader constraint checking
707 if (!this_oop()->is_shared()) {
708 ResourceMark rm(THREAD);
709 this_oop->vtable()->initialize_vtable(true, CHECK_false);
710 this_oop->itable()->initialize_itable(true, CHECK_false);
711 }
712 #ifdef ASSERT
713 else {
714 ResourceMark rm(THREAD);
715 this_oop->vtable()->verify(tty, true);
716 // In case itable verification is ever added.
717 // this_oop->itable()->verify(tty, true);
718 }
719 #endif
720 this_oop->set_init_state(linked);
721 if (JvmtiExport::should_post_class_prepare()) {
722 Thread *thread = THREAD;
723 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
724 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
725 }
726 }
727 }
728 return true;
729 }
730
731
732 // Rewrite the byte codes of all of the methods of a class.
733 // The rewriter must be called exactly once. Rewriting must happen after
734 // verification but before the first method of the class is executed.
735 void InstanceKlass::rewrite_class(TRAPS) {
736 assert(is_loaded(), "must be loaded");
737 instanceKlassHandle this_oop(THREAD, this);
738 if (this_oop->is_rewritten()) {
739 assert(this_oop()->is_shared(), "rewriting an unshared class?");
740 return;
741 }
742 Rewriter::rewrite(this_oop, CHECK);
743 this_oop->set_rewritten();
744 }
745
746 // Now relocate and link method entry points after class is rewritten.
747 // This is outside is_rewritten flag. In case of an exception, it can be
748 // executed more than once.
749 void InstanceKlass::link_methods(TRAPS) {
750 int len = methods()->length();
751 for (int i = len-1; i >= 0; i--) {
752 methodHandle m(THREAD, methods()->at(i));
753
754 // Set up method entry points for compiler and interpreter .
755 m->link_method(m, CHECK);
756
757 // This is for JVMTI and unrelated to relocator but the last thing we do
758 #ifdef ASSERT
759 if (StressMethodComparator) {
760 ResourceMark rm(THREAD);
761 static int nmc = 0;
762 for (int j = i; j >= 0 && j >= i-4; j--) {
763 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
764 bool z = MethodComparator::methods_EMCP(m(),
765 methods()->at(j));
766 if (j == i && !z) {
767 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
768 assert(z, "method must compare equal to itself");
769 }
770 }
771 }
772 #endif //ASSERT
773 }
774 }
775
776
777 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
778 // Make sure klass is linked (verified) before initialization
779 // A class could already be verified, since it has been reflected upon.
780 this_oop->link_class(CHECK);
781
782 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
783
784 bool wait = false;
785
786 // refer to the JVM book page 47 for description of steps
787 // Step 1
788 {
789 oop init_lock = this_oop->init_lock();
790 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
791
792 Thread *self = THREAD; // it's passed the current thread
793
794 // Step 2
795 // If we were to use wait() instead of waitInterruptibly() then
796 // we might end up throwing IE from link/symbol resolution sites
797 // that aren't expected to throw. This would wreak havoc. See 6320309.
798 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
799 wait = true;
800 ol.waitUninterruptibly(CHECK);
801 }
802
803 // Step 3
804 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
805 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
806 return;
807 }
808
809 // Step 4
810 if (this_oop->is_initialized()) {
811 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
812 return;
813 }
814
815 // Step 5
816 if (this_oop->is_in_error_state()) {
817 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
818 ResourceMark rm(THREAD);
819 const char* desc = "Could not initialize class ";
820 const char* className = this_oop->external_name();
821 size_t msglen = strlen(desc) + strlen(className) + 1;
822 char* message = NEW_RESOURCE_ARRAY(char, msglen);
823 if (NULL == message) {
824 // Out of memory: can't create detailed error message
825 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
826 } else {
827 jio_snprintf(message, msglen, "%s%s", desc, className);
828 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
829 }
830 }
831
832 // Step 6
833 this_oop->set_init_state(being_initialized);
834 this_oop->set_init_thread(self);
835 }
836
837 // Step 7
838 Klass* super_klass = this_oop->super();
839 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
840 super_klass->initialize(THREAD);
841
842 if (HAS_PENDING_EXCEPTION) {
843 Handle e(THREAD, PENDING_EXCEPTION);
844 CLEAR_PENDING_EXCEPTION;
845 {
846 EXCEPTION_MARK;
847 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
848 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
849 }
850 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
851 THROW_OOP(e());
852 }
853 }
854
855 if (this_oop->has_default_methods()) {
856 // Step 7.5: initialize any interfaces which have default methods
857 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
858 Klass* iface = this_oop->local_interfaces()->at(i);
859 InstanceKlass* ik = InstanceKlass::cast(iface);
860 if (ik->has_default_methods() && ik->should_be_initialized()) {
861 ik->initialize(THREAD);
862
863 if (HAS_PENDING_EXCEPTION) {
864 Handle e(THREAD, PENDING_EXCEPTION);
865 CLEAR_PENDING_EXCEPTION;
866 {
867 EXCEPTION_MARK;
868 // Locks object, set state, and notify all waiting threads
869 this_oop->set_initialization_state_and_notify(
870 initialization_error, THREAD);
871
872 // ignore any exception thrown, superclass initialization error is
873 // thrown below
874 CLEAR_PENDING_EXCEPTION;
875 }
876 DTRACE_CLASSINIT_PROBE_WAIT(
877 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
878 THROW_OOP(e());
879 }
880 }
881 }
882 }
883
884 // Step 8
885 {
886 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
887 JavaThread* jt = (JavaThread*)THREAD;
888 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
889 // Timer includes any side effects of class initialization (resolution,
890 // etc), but not recursive entry into call_class_initializer().
891 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
892 ClassLoader::perf_class_init_selftime(),
893 ClassLoader::perf_classes_inited(),
894 jt->get_thread_stat()->perf_recursion_counts_addr(),
895 jt->get_thread_stat()->perf_timers_addr(),
896 PerfClassTraceTime::CLASS_CLINIT);
897 this_oop->call_class_initializer(THREAD);
898 }
899
900 // Step 9
901 if (!HAS_PENDING_EXCEPTION) {
902 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
903 { ResourceMark rm(THREAD);
904 debug_only(this_oop->vtable()->verify(tty, true);)
905 }
906 }
907 else {
908 // Step 10 and 11
909 Handle e(THREAD, PENDING_EXCEPTION);
910 CLEAR_PENDING_EXCEPTION;
911 {
912 EXCEPTION_MARK;
913 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
914 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
915 }
916 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
917 if (e->is_a(SystemDictionary::Error_klass())) {
918 THROW_OOP(e());
919 } else {
920 JavaCallArguments args(e);
921 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
922 vmSymbols::throwable_void_signature(),
923 &args);
924 }
925 }
926 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
927 }
928
929
930 // Note: implementation moved to static method to expose the this pointer.
931 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
932 instanceKlassHandle kh(THREAD, this);
933 set_initialization_state_and_notify_impl(kh, state, CHECK);
934 }
935
936 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
937 oop init_lock = this_oop->init_lock();
938 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
939 this_oop->set_init_state(state);
940 this_oop->fence_and_clear_init_lock();
941 ol.notify_all(CHECK);
942 }
943
944 // The embedded _implementor field can only record one implementor.
945 // When there are more than one implementors, the _implementor field
946 // is set to the interface Klass* itself. Following are the possible
947 // values for the _implementor field:
948 // NULL - no implementor
949 // implementor Klass* - one implementor
950 // self - more than one implementor
951 //
952 // The _implementor field only exists for interfaces.
953 void InstanceKlass::add_implementor(Klass* k) {
954 assert(Compile_lock->owned_by_self(), "");
955 assert(is_interface(), "not interface");
956 // Filter out my subinterfaces.
957 // (Note: Interfaces are never on the subklass list.)
958 if (InstanceKlass::cast(k)->is_interface()) return;
959
960 // Filter out subclasses whose supers already implement me.
961 // (Note: CHA must walk subclasses of direct implementors
962 // in order to locate indirect implementors.)
963 Klass* sk = InstanceKlass::cast(k)->super();
964 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
965 // We only need to check one immediate superclass, since the
966 // implements_interface query looks at transitive_interfaces.
967 // Any supers of the super have the same (or fewer) transitive_interfaces.
968 return;
969
970 Klass* ik = implementor();
971 if (ik == NULL) {
972 set_implementor(k);
973 } else if (ik != this) {
974 // There is already an implementor. Use itself as an indicator of
975 // more than one implementors.
976 set_implementor(this);
977 }
978
979 // The implementor also implements the transitive_interfaces
980 for (int index = 0; index < local_interfaces()->length(); index++) {
981 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
982 }
983 }
984
985 void InstanceKlass::init_implementor() {
986 if (is_interface()) {
987 set_implementor(NULL);
988 }
989 }
990
991
992 void InstanceKlass::process_interfaces(Thread *thread) {
993 // link this class into the implementors list of every interface it implements
994 Klass* this_as_klass_oop = this;
995 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
996 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
997 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
998 assert(interf->is_interface(), "expected interface");
999 interf->add_implementor(this_as_klass_oop);
1000 }
1001 }
1002
1003 bool InstanceKlass::can_be_primary_super_slow() const {
1004 if (is_interface())
1005 return false;
1006 else
1007 return Klass::can_be_primary_super_slow();
1008 }
1009
1010 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1011 // The secondaries are the implemented interfaces.
1012 InstanceKlass* ik = InstanceKlass::cast(this);
1013 Array<Klass*>* interfaces = ik->transitive_interfaces();
1014 int num_secondaries = num_extra_slots + interfaces->length();
1015 if (num_secondaries == 0) {
1016 // Must share this for correct bootstrapping!
1017 set_secondary_supers(Universe::the_empty_klass_array());
1018 return NULL;
1019 } else if (num_extra_slots == 0) {
1020 // The secondary super list is exactly the same as the transitive interfaces.
1021 // Redefine classes has to be careful not to delete this!
1022 set_secondary_supers(interfaces);
1023 return NULL;
1024 } else {
1025 // Copy transitive interfaces to a temporary growable array to be constructed
1026 // into the secondary super list with extra slots.
1027 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1028 for (int i = 0; i < interfaces->length(); i++) {
1029 secondaries->push(interfaces->at(i));
1030 }
1031 return secondaries;
1032 }
1033 }
1034
1035 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1036 if (k->is_interface()) {
1037 return implements_interface(k);
1038 } else {
1039 return Klass::compute_is_subtype_of(k);
1040 }
1041 }
1042
1043 bool InstanceKlass::implements_interface(Klass* k) const {
1044 if (this == k) return true;
1045 assert(k->is_interface(), "should be an interface class");
1046 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1047 if (transitive_interfaces()->at(i) == k) {
1048 return true;
1049 }
1050 }
1051 return false;
1052 }
1053
1054 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1055 // Verify direct super interface
1056 if (this == k) return true;
1057 assert(k->is_interface(), "should be an interface class");
1058 for (int i = 0; i < local_interfaces()->length(); i++) {
1059 if (local_interfaces()->at(i) == k) {
1060 return true;
1061 }
1062 }
1063 return false;
1064 }
1065
1066 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1067 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1068 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1069 report_java_out_of_memory("Requested array size exceeds VM limit");
1070 JvmtiExport::post_array_size_exhausted();
1071 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1072 }
1073 int size = objArrayOopDesc::object_size(length);
1074 Klass* ak = array_klass(n, CHECK_NULL);
1075 KlassHandle h_ak (THREAD, ak);
1076 objArrayOop o =
1077 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1078 return o;
1079 }
1080
1081 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1082 if (TraceFinalizerRegistration) {
1083 tty->print("Registered ");
1084 i->print_value_on(tty);
1085 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1086 }
1087 instanceHandle h_i(THREAD, i);
1088 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1089 JavaValue result(T_VOID);
1090 JavaCallArguments args(h_i);
1091 methodHandle mh (THREAD, Universe::finalizer_register_method());
1092 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1093 return h_i();
1094 }
1095
1096 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1097 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1098 int size = size_helper(); // Query before forming handle.
1099
1100 KlassHandle h_k(THREAD, this);
1101
1102 instanceOop i;
1103
1104 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1105 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1106 i = register_finalizer(i, CHECK_NULL);
1107 }
1108 return i;
1109 }
1110
1111 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1112 if (is_interface() || is_abstract()) {
1113 ResourceMark rm(THREAD);
1114 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1115 : vmSymbols::java_lang_InstantiationException(), external_name());
1116 }
1117 if (this == SystemDictionary::Class_klass()) {
1118 ResourceMark rm(THREAD);
1119 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1120 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1121 }
1122 }
1123
1124 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1125 instanceKlassHandle this_oop(THREAD, this);
1126 return array_klass_impl(this_oop, or_null, n, THREAD);
1127 }
1128
1129 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1130 if (this_oop->array_klasses() == NULL) {
1131 if (or_null) return NULL;
1132
1133 ResourceMark rm;
1134 JavaThread *jt = (JavaThread *)THREAD;
1135 {
1136 // Atomic creation of array_klasses
1137 MutexLocker mc(Compile_lock, THREAD); // for vtables
1138 MutexLocker ma(MultiArray_lock, THREAD);
1139
1140 // Check if update has already taken place
1141 if (this_oop->array_klasses() == NULL) {
1142 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1143 this_oop->set_array_klasses(k);
1144 }
1145 }
1146 }
1147 // _this will always be set at this point
1148 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1149 if (or_null) {
1150 return oak->array_klass_or_null(n);
1151 }
1152 return oak->array_klass(n, CHECK_NULL);
1153 }
1154
1155 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1156 return array_klass_impl(or_null, 1, THREAD);
1157 }
1158
1159 void InstanceKlass::call_class_initializer(TRAPS) {
1160 instanceKlassHandle ik (THREAD, this);
1161 call_class_initializer_impl(ik, THREAD);
1162 }
1163
1164 static int call_class_initializer_impl_counter = 0; // for debugging
1165
1166 Method* InstanceKlass::class_initializer() {
1167 Method* clinit = find_method(
1168 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1169 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1170 return clinit;
1171 }
1172 return NULL;
1173 }
1174
1175 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1176 if (ReplayCompiles &&
1177 (ReplaySuppressInitializers == 1 ||
1178 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1179 // Hide the existence of the initializer for the purpose of replaying the compile
1180 return;
1181 }
1182
1183 methodHandle h_method(THREAD, this_oop->class_initializer());
1184 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1185 if (TraceClassInitialization) {
1186 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1187 this_oop->name()->print_value();
1188 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1189 }
1190 if (h_method() != NULL) {
1191 JavaCallArguments args; // No arguments
1192 JavaValue result(T_VOID);
1193 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1194 }
1195 }
1196
1197
1198 void InstanceKlass::mask_for(methodHandle method, int bci,
1199 InterpreterOopMap* entry_for) {
1200 // Dirty read, then double-check under a lock.
1201 if (_oop_map_cache == NULL) {
1202 // Otherwise, allocate a new one.
1203 MutexLocker x(OopMapCacheAlloc_lock);
1204 // First time use. Allocate a cache in C heap
1205 if (_oop_map_cache == NULL) {
1206 _oop_map_cache = new OopMapCache();
1207 }
1208 }
1209 // _oop_map_cache is constant after init; lookup below does is own locking.
1210 _oop_map_cache->lookup(method, bci, entry_for);
1211 }
1212
1213
1214 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1215 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1216 Symbol* f_name = fs.name();
1217 Symbol* f_sig = fs.signature();
1218 if (f_name == name && f_sig == sig) {
1219 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1220 return true;
1221 }
1222 }
1223 return false;
1224 }
1225
1226
1227 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1228 const int n = local_interfaces()->length();
1229 for (int i = 0; i < n; i++) {
1230 Klass* intf1 = local_interfaces()->at(i);
1231 assert(intf1->is_interface(), "just checking type");
1232 // search for field in current interface
1233 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1234 assert(fd->is_static(), "interface field must be static");
1235 return intf1;
1236 }
1237 // search for field in direct superinterfaces
1238 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1239 if (intf2 != NULL) return intf2;
1240 }
1241 // otherwise field lookup fails
1242 return NULL;
1243 }
1244
1245
1246 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1247 // search order according to newest JVM spec (5.4.3.2, p.167).
1248 // 1) search for field in current klass
1249 if (find_local_field(name, sig, fd)) {
1250 return const_cast<InstanceKlass*>(this);
1251 }
1252 // 2) search for field recursively in direct superinterfaces
1253 { Klass* intf = find_interface_field(name, sig, fd);
1254 if (intf != NULL) return intf;
1255 }
1256 // 3) apply field lookup recursively if superclass exists
1257 { Klass* supr = super();
1258 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1259 }
1260 // 4) otherwise field lookup fails
1261 return NULL;
1262 }
1263
1264
1265 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1266 // search order according to newest JVM spec (5.4.3.2, p.167).
1267 // 1) search for field in current klass
1268 if (find_local_field(name, sig, fd)) {
1269 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1270 }
1271 // 2) search for field recursively in direct superinterfaces
1272 if (is_static) {
1273 Klass* intf = find_interface_field(name, sig, fd);
1274 if (intf != NULL) return intf;
1275 }
1276 // 3) apply field lookup recursively if superclass exists
1277 { Klass* supr = super();
1278 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1279 }
1280 // 4) otherwise field lookup fails
1281 return NULL;
1282 }
1283
1284
1285 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1286 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1287 if (fs.offset() == offset) {
1288 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1289 if (fd->is_static() == is_static) return true;
1290 }
1291 }
1292 return false;
1293 }
1294
1295
1296 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1297 Klass* klass = const_cast<InstanceKlass*>(this);
1298 while (klass != NULL) {
1299 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1300 return true;
1301 }
1302 klass = klass->super();
1303 }
1304 return false;
1305 }
1306
1307
1308 void InstanceKlass::methods_do(void f(Method* method)) {
1309 int len = methods()->length();
1310 for (int index = 0; index < len; index++) {
1311 Method* m = methods()->at(index);
1312 assert(m->is_method(), "must be method");
1313 f(m);
1314 }
1315 }
1316
1317
1318 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1319 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1320 if (fs.access_flags().is_static()) {
1321 fieldDescriptor& fd = fs.field_descriptor();
1322 cl->do_field(&fd);
1323 }
1324 }
1325 }
1326
1327
1328 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
1329 instanceKlassHandle h_this(THREAD, this);
1330 do_local_static_fields_impl(h_this, f, CHECK);
1331 }
1332
1333
1334 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
1335 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
1336 if (fs.access_flags().is_static()) {
1337 fieldDescriptor& fd = fs.field_descriptor();
1338 f(&fd, CHECK);
1339 }
1340 }
1341 }
1342
1343
1344 static int compare_fields_by_offset(int* a, int* b) {
1345 return a[0] - b[0];
1346 }
1347
1348 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1349 InstanceKlass* super = superklass();
1350 if (super != NULL) {
1351 super->do_nonstatic_fields(cl);
1352 }
1353 fieldDescriptor fd;
1354 int length = java_fields_count();
1355 // In DebugInfo nonstatic fields are sorted by offset.
1356 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1357 int j = 0;
1358 for (int i = 0; i < length; i += 1) {
1359 fd.reinitialize(this, i);
1360 if (!fd.is_static()) {
1361 fields_sorted[j + 0] = fd.offset();
1362 fields_sorted[j + 1] = i;
1363 j += 2;
1364 }
1365 }
1366 if (j > 0) {
1367 length = j;
1368 // _sort_Fn is defined in growableArray.hpp.
1369 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1370 for (int i = 0; i < length; i += 2) {
1371 fd.reinitialize(this, fields_sorted[i + 1]);
1372 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1373 cl->do_field(&fd);
1374 }
1375 }
1376 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1377 }
1378
1379
1380 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1381 if (array_klasses() != NULL)
1382 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1383 }
1384
1385 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1386 if (array_klasses() != NULL)
1387 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1388 }
1389
1390 #ifdef ASSERT
1391 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1392 int len = methods->length();
1393 for (int index = 0; index < len; index++) {
1394 Method* m = methods->at(index);
1395 assert(m->is_method(), "must be method");
1396 if (m->signature() == signature && m->name() == name) {
1397 return index;
1398 }
1399 }
1400 return -1;
1401 }
1402 #endif
1403
1404 static int binary_search(Array<Method*>* methods, Symbol* name) {
1405 int len = methods->length();
1406 // methods are sorted, so do binary search
1407 int l = 0;
1408 int h = len - 1;
1409 while (l <= h) {
1410 int mid = (l + h) >> 1;
1411 Method* m = methods->at(mid);
1412 assert(m->is_method(), "must be method");
1413 int res = m->name()->fast_compare(name);
1414 if (res == 0) {
1415 return mid;
1416 } else if (res < 0) {
1417 l = mid + 1;
1418 } else {
1419 h = mid - 1;
1420 }
1421 }
1422 return -1;
1423 }
1424
1425 // find_method looks up the name/signature in the local methods array
1426 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1427 return InstanceKlass::find_method(methods(), name, signature);
1428 }
1429
1430 // find_instance_method looks up the name/signature in the local methods array
1431 // and skips over static methods
1432 Method* InstanceKlass::find_instance_method(
1433 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1434 Method* meth = InstanceKlass::find_method(methods, name, signature);
1435 if (meth != NULL && meth->is_static()) {
1436 meth = NULL;
1437 }
1438 return meth;
1439 }
1440
1441 // find_method looks up the name/signature in the local methods array
1442 Method* InstanceKlass::find_method(
1443 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1444 int hit = find_method_index(methods, name, signature);
1445 return hit >= 0 ? methods->at(hit): NULL;
1446 }
1447
1448 // Used directly for default_methods to find the index into the
1449 // default_vtable_indices, and indirectly by find_method
1450 // find_method_index looks in the local methods array to return the index
1451 // of the matching name/signature
1452 int InstanceKlass::find_method_index(
1453 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1454 int hit = binary_search(methods, name);
1455 if (hit != -1) {
1456 Method* m = methods->at(hit);
1457 // Do linear search to find matching signature. First, quick check
1458 // for common case
1459 if (m->signature() == signature) return hit;
1460 // search downwards through overloaded methods
1461 int i;
1462 for (i = hit - 1; i >= 0; --i) {
1463 Method* m = methods->at(i);
1464 assert(m->is_method(), "must be method");
1465 if (m->name() != name) break;
1466 if (m->signature() == signature) return i;
1467 }
1468 // search upwards
1469 for (i = hit + 1; i < methods->length(); ++i) {
1470 Method* m = methods->at(i);
1471 assert(m->is_method(), "must be method");
1472 if (m->name() != name) break;
1473 if (m->signature() == signature) return i;
1474 }
1475 // not found
1476 #ifdef ASSERT
1477 int index = linear_search(methods, name, signature);
1478 assert(index == -1, err_msg("binary search should have found entry %d", index));
1479 #endif
1480 }
1481 return -1;
1482 }
1483 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1484 return find_method_by_name(methods(), name, end);
1485 }
1486
1487 int InstanceKlass::find_method_by_name(
1488 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1489 assert(end_ptr != NULL, "just checking");
1490 int start = binary_search(methods, name);
1491 int end = start + 1;
1492 if (start != -1) {
1493 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1494 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1495 *end_ptr = end;
1496 return start;
1497 }
1498 return -1;
1499 }
1500
1501 // uncached_lookup_method searches both the local class methods array and all
1502 // superclasses methods arrays, skipping any overpass methods in superclasses.
1503 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1504 Klass* klass = const_cast<InstanceKlass*>(this);
1505 bool dont_ignore_overpasses = true; // For the class being searched, find its overpasses.
1506 while (klass != NULL) {
1507 Method* method = InstanceKlass::cast(klass)->find_method(name, signature);
1508 if ((method != NULL) && (dont_ignore_overpasses || !method->is_overpass())) {
1509 return method;
1510 }
1511 klass = InstanceKlass::cast(klass)->super();
1512 dont_ignore_overpasses = false; // Ignore overpass methods in all superclasses.
1513 }
1514 return NULL;
1515 }
1516
1517 // lookup a method in the default methods list then in all transitive interfaces
1518 // Do NOT return private or static methods
1519 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1520 Symbol* signature) const {
1521 Method* m = NULL;
1522 if (default_methods() != NULL) {
1523 m = find_method(default_methods(), name, signature);
1524 }
1525 // Look up interfaces
1526 if (m == NULL) {
1527 m = lookup_method_in_all_interfaces(name, signature, false);
1528 }
1529 return m;
1530 }
1531
1532 // lookup a method in all the interfaces that this class implements
1533 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1534 // They should only be found in the initial InterfaceMethodRef
1535 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1536 Symbol* signature,
1537 bool skip_default_methods) const {
1538 Array<Klass*>* all_ifs = transitive_interfaces();
1539 int num_ifs = all_ifs->length();
1540 InstanceKlass *ik = NULL;
1541 for (int i = 0; i < num_ifs; i++) {
1542 ik = InstanceKlass::cast(all_ifs->at(i));
1543 Method* m = ik->lookup_method(name, signature);
1544 if (m != NULL && m->is_public() && !m->is_static() &&
1545 (!skip_default_methods || !m->is_default_method())) {
1546 return m;
1547 }
1548 }
1549 return NULL;
1550 }
1551
1552 /* jni_id_for_impl for jfieldIds only */
1553 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1554 MutexLocker ml(JfieldIdCreation_lock);
1555 // Retry lookup after we got the lock
1556 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1557 if (probe == NULL) {
1558 // Slow case, allocate new static field identifier
1559 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1560 this_oop->set_jni_ids(probe);
1561 }
1562 return probe;
1563 }
1564
1565
1566 /* jni_id_for for jfieldIds only */
1567 JNIid* InstanceKlass::jni_id_for(int offset) {
1568 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1569 if (probe == NULL) {
1570 probe = jni_id_for_impl(this, offset);
1571 }
1572 return probe;
1573 }
1574
1575 u2 InstanceKlass::enclosing_method_data(int offset) {
1576 Array<jushort>* inner_class_list = inner_classes();
1577 if (inner_class_list == NULL) {
1578 return 0;
1579 }
1580 int length = inner_class_list->length();
1581 if (length % inner_class_next_offset == 0) {
1582 return 0;
1583 } else {
1584 int index = length - enclosing_method_attribute_size;
1585 assert(offset < enclosing_method_attribute_size, "invalid offset");
1586 return inner_class_list->at(index + offset);
1587 }
1588 }
1589
1590 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1591 u2 method_index) {
1592 Array<jushort>* inner_class_list = inner_classes();
1593 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1594 int length = inner_class_list->length();
1595 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1596 int index = length - enclosing_method_attribute_size;
1597 inner_class_list->at_put(
1598 index + enclosing_method_class_index_offset, class_index);
1599 inner_class_list->at_put(
1600 index + enclosing_method_method_index_offset, method_index);
1601 }
1602 }
1603
1604 // Lookup or create a jmethodID.
1605 // This code is called by the VMThread and JavaThreads so the
1606 // locking has to be done very carefully to avoid deadlocks
1607 // and/or other cache consistency problems.
1608 //
1609 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1610 size_t idnum = (size_t)method_h->method_idnum();
1611 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1612 size_t length = 0;
1613 jmethodID id = NULL;
1614
1615 // We use a double-check locking idiom here because this cache is
1616 // performance sensitive. In the normal system, this cache only
1617 // transitions from NULL to non-NULL which is safe because we use
1618 // release_set_methods_jmethod_ids() to advertise the new cache.
1619 // A partially constructed cache should never be seen by a racing
1620 // thread. We also use release_store_ptr() to save a new jmethodID
1621 // in the cache so a partially constructed jmethodID should never be
1622 // seen either. Cache reads of existing jmethodIDs proceed without a
1623 // lock, but cache writes of a new jmethodID requires uniqueness and
1624 // creation of the cache itself requires no leaks so a lock is
1625 // generally acquired in those two cases.
1626 //
1627 // If the RedefineClasses() API has been used, then this cache can
1628 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1629 // Cache creation requires no leaks and we require safety between all
1630 // cache accesses and freeing of the old cache so a lock is generally
1631 // acquired when the RedefineClasses() API has been used.
1632
1633 if (jmeths != NULL) {
1634 // the cache already exists
1635 if (!ik_h->idnum_can_increment()) {
1636 // the cache can't grow so we can just get the current values
1637 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1638 } else {
1639 // cache can grow so we have to be more careful
1640 if (Threads::number_of_threads() == 0 ||
1641 SafepointSynchronize::is_at_safepoint()) {
1642 // we're single threaded or at a safepoint - no locking needed
1643 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1644 } else {
1645 MutexLocker ml(JmethodIdCreation_lock);
1646 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1647 }
1648 }
1649 }
1650 // implied else:
1651 // we need to allocate a cache so default length and id values are good
1652
1653 if (jmeths == NULL || // no cache yet
1654 length <= idnum || // cache is too short
1655 id == NULL) { // cache doesn't contain entry
1656
1657 // This function can be called by the VMThread so we have to do all
1658 // things that might block on a safepoint before grabbing the lock.
1659 // Otherwise, we can deadlock with the VMThread or have a cache
1660 // consistency issue. These vars keep track of what we might have
1661 // to free after the lock is dropped.
1662 jmethodID to_dealloc_id = NULL;
1663 jmethodID* to_dealloc_jmeths = NULL;
1664
1665 // may not allocate new_jmeths or use it if we allocate it
1666 jmethodID* new_jmeths = NULL;
1667 if (length <= idnum) {
1668 // allocate a new cache that might be used
1669 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1670 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1671 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1672 // cache size is stored in element[0], other elements offset by one
1673 new_jmeths[0] = (jmethodID)size;
1674 }
1675
1676 // allocate a new jmethodID that might be used
1677 jmethodID new_id = NULL;
1678 if (method_h->is_old() && !method_h->is_obsolete()) {
1679 // The method passed in is old (but not obsolete), we need to use the current version
1680 Method* current_method = ik_h->method_with_idnum((int)idnum);
1681 assert(current_method != NULL, "old and but not obsolete, so should exist");
1682 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1683 } else {
1684 // It is the current version of the method or an obsolete method,
1685 // use the version passed in
1686 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1687 }
1688
1689 if (Threads::number_of_threads() == 0 ||
1690 SafepointSynchronize::is_at_safepoint()) {
1691 // we're single threaded or at a safepoint - no locking needed
1692 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1693 &to_dealloc_id, &to_dealloc_jmeths);
1694 } else {
1695 MutexLocker ml(JmethodIdCreation_lock);
1696 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1697 &to_dealloc_id, &to_dealloc_jmeths);
1698 }
1699
1700 // The lock has been dropped so we can free resources.
1701 // Free up either the old cache or the new cache if we allocated one.
1702 if (to_dealloc_jmeths != NULL) {
1703 FreeHeap(to_dealloc_jmeths);
1704 }
1705 // free up the new ID since it wasn't needed
1706 if (to_dealloc_id != NULL) {
1707 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1708 }
1709 }
1710 return id;
1711 }
1712
1713
1714 // Common code to fetch the jmethodID from the cache or update the
1715 // cache with the new jmethodID. This function should never do anything
1716 // that causes the caller to go to a safepoint or we can deadlock with
1717 // the VMThread or have cache consistency issues.
1718 //
1719 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1720 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1721 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1722 jmethodID** to_dealloc_jmeths_p) {
1723 assert(new_id != NULL, "sanity check");
1724 assert(to_dealloc_id_p != NULL, "sanity check");
1725 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1726 assert(Threads::number_of_threads() == 0 ||
1727 SafepointSynchronize::is_at_safepoint() ||
1728 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1729
1730 // reacquire the cache - we are locked, single threaded or at a safepoint
1731 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1732 jmethodID id = NULL;
1733 size_t length = 0;
1734
1735 if (jmeths == NULL || // no cache yet
1736 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1737 if (jmeths != NULL) {
1738 // copy any existing entries from the old cache
1739 for (size_t index = 0; index < length; index++) {
1740 new_jmeths[index+1] = jmeths[index+1];
1741 }
1742 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1743 }
1744 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1745 } else {
1746 // fetch jmethodID (if any) from the existing cache
1747 id = jmeths[idnum+1];
1748 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1749 }
1750 if (id == NULL) {
1751 // No matching jmethodID in the existing cache or we have a new
1752 // cache or we just grew the cache. This cache write is done here
1753 // by the first thread to win the foot race because a jmethodID
1754 // needs to be unique once it is generally available.
1755 id = new_id;
1756
1757 // The jmethodID cache can be read while unlocked so we have to
1758 // make sure the new jmethodID is complete before installing it
1759 // in the cache.
1760 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1761 } else {
1762 *to_dealloc_id_p = new_id; // save new id for later delete
1763 }
1764 return id;
1765 }
1766
1767
1768 // Common code to get the jmethodID cache length and the jmethodID
1769 // value at index idnum if there is one.
1770 //
1771 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1772 size_t idnum, size_t *length_p, jmethodID* id_p) {
1773 assert(cache != NULL, "sanity check");
1774 assert(length_p != NULL, "sanity check");
1775 assert(id_p != NULL, "sanity check");
1776
1777 // cache size is stored in element[0], other elements offset by one
1778 *length_p = (size_t)cache[0];
1779 if (*length_p <= idnum) { // cache is too short
1780 *id_p = NULL;
1781 } else {
1782 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1783 }
1784 }
1785
1786
1787 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1788 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1789 size_t idnum = (size_t)method->method_idnum();
1790 jmethodID* jmeths = methods_jmethod_ids_acquire();
1791 size_t length; // length assigned as debugging crumb
1792 jmethodID id = NULL;
1793 if (jmeths != NULL && // If there is a cache
1794 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1795 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1796 }
1797 return id;
1798 }
1799
1800
1801 //
1802 // Walk the list of dependent nmethods searching for nmethods which
1803 // are dependent on the changes that were passed in and mark them for
1804 // deoptimization. Returns the number of nmethods found.
1805 //
1806 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1807 assert_locked_or_safepoint(CodeCache_lock);
1808 int found = 0;
1809 nmethodBucket* b = _dependencies;
1810 while (b != NULL) {
1811 nmethod* nm = b->get_nmethod();
1812 // since dependencies aren't removed until an nmethod becomes a zombie,
1813 // the dependency list may contain nmethods which aren't alive.
1814 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1815 if (TraceDependencies) {
1816 ResourceMark rm;
1817 tty->print_cr("Marked for deoptimization");
1818 tty->print_cr(" context = %s", this->external_name());
1819 changes.print();
1820 nm->print();
1821 nm->print_dependencies();
1822 }
1823 nm->mark_for_deoptimization();
1824 found++;
1825 }
1826 b = b->next();
1827 }
1828 return found;
1829 }
1830
1831
1832 //
1833 // Add an nmethodBucket to the list of dependencies for this nmethod.
1834 // It's possible that an nmethod has multiple dependencies on this klass
1835 // so a count is kept for each bucket to guarantee that creation and
1836 // deletion of dependencies is consistent.
1837 //
1838 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1839 assert_locked_or_safepoint(CodeCache_lock);
1840 nmethodBucket* b = _dependencies;
1841 nmethodBucket* last = NULL;
1842 while (b != NULL) {
1843 if (nm == b->get_nmethod()) {
1844 b->increment();
1845 return;
1846 }
1847 b = b->next();
1848 }
1849 _dependencies = new nmethodBucket(nm, _dependencies);
1850 }
1851
1852
1853 //
1854 // Decrement count of the nmethod in the dependency list and remove
1855 // the bucket competely when the count goes to 0. This method must
1856 // find a corresponding bucket otherwise there's a bug in the
1857 // recording of dependecies.
1858 //
1859 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1860 assert_locked_or_safepoint(CodeCache_lock);
1861 nmethodBucket* b = _dependencies;
1862 nmethodBucket* last = NULL;
1863 while (b != NULL) {
1864 if (nm == b->get_nmethod()) {
1865 if (b->decrement() == 0) {
1866 if (last == NULL) {
1867 _dependencies = b->next();
1868 } else {
1869 last->set_next(b->next());
1870 }
1871 delete b;
1872 }
1873 return;
1874 }
1875 last = b;
1876 b = b->next();
1877 }
1878 #ifdef ASSERT
1879 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1880 nm->print();
1881 #endif // ASSERT
1882 ShouldNotReachHere();
1883 }
1884
1885
1886 #ifndef PRODUCT
1887 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1888 nmethodBucket* b = _dependencies;
1889 int idx = 0;
1890 while (b != NULL) {
1891 nmethod* nm = b->get_nmethod();
1892 tty->print("[%d] count=%d { ", idx++, b->count());
1893 if (!verbose) {
1894 nm->print_on(tty, "nmethod");
1895 tty->print_cr(" } ");
1896 } else {
1897 nm->print();
1898 nm->print_dependencies();
1899 tty->print_cr("--- } ");
1900 }
1901 b = b->next();
1902 }
1903 }
1904
1905
1906 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1907 nmethodBucket* b = _dependencies;
1908 while (b != NULL) {
1909 if (nm == b->get_nmethod()) {
1910 return true;
1911 }
1912 b = b->next();
1913 }
1914 return false;
1915 }
1916 #endif //PRODUCT
1917
1918
1919 // Garbage collection
1920
1921 #ifdef ASSERT
1922 template <class T> void assert_is_in(T *p) {
1923 T heap_oop = oopDesc::load_heap_oop(p);
1924 if (!oopDesc::is_null(heap_oop)) {
1925 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1926 assert(Universe::heap()->is_in(o), "should be in heap");
1927 }
1928 }
1929 template <class T> void assert_is_in_closed_subset(T *p) {
1930 T heap_oop = oopDesc::load_heap_oop(p);
1931 if (!oopDesc::is_null(heap_oop)) {
1932 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1933 assert(Universe::heap()->is_in_closed_subset(o),
1934 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1935 }
1936 }
1937 template <class T> void assert_is_in_reserved(T *p) {
1938 T heap_oop = oopDesc::load_heap_oop(p);
1939 if (!oopDesc::is_null(heap_oop)) {
1940 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1941 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1942 }
1943 }
1944 template <class T> void assert_nothing(T *p) {}
1945
1946 #else
1947 template <class T> void assert_is_in(T *p) {}
1948 template <class T> void assert_is_in_closed_subset(T *p) {}
1949 template <class T> void assert_is_in_reserved(T *p) {}
1950 template <class T> void assert_nothing(T *p) {}
1951 #endif // ASSERT
1952
1953 //
1954 // Macros that iterate over areas of oops which are specialized on type of
1955 // oop pointer either narrow or wide, depending on UseCompressedOops
1956 //
1957 // Parameters are:
1958 // T - type of oop to point to (either oop or narrowOop)
1959 // start_p - starting pointer for region to iterate over
1960 // count - number of oops or narrowOops to iterate over
1961 // do_oop - action to perform on each oop (it's arbitrary C code which
1962 // makes it more efficient to put in a macro rather than making
1963 // it a template function)
1964 // assert_fn - assert function which is template function because performance
1965 // doesn't matter when enabled.
1966 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1967 T, start_p, count, do_oop, \
1968 assert_fn) \
1969 { \
1970 T* p = (T*)(start_p); \
1971 T* const end = p + (count); \
1972 while (p < end) { \
1973 (assert_fn)(p); \
1974 do_oop; \
1975 ++p; \
1976 } \
1977 }
1978
1979 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1980 T, start_p, count, do_oop, \
1981 assert_fn) \
1982 { \
1983 T* const start = (T*)(start_p); \
1984 T* p = start + (count); \
1985 while (start < p) { \
1986 --p; \
1987 (assert_fn)(p); \
1988 do_oop; \
1989 } \
1990 }
1991
1992 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1993 T, start_p, count, low, high, \
1994 do_oop, assert_fn) \
1995 { \
1996 T* const l = (T*)(low); \
1997 T* const h = (T*)(high); \
1998 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1999 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2000 "bounded region must be properly aligned"); \
2001 T* p = (T*)(start_p); \
2002 T* end = p + (count); \
2003 if (p < l) p = l; \
2004 if (end > h) end = h; \
2005 while (p < end) { \
2006 (assert_fn)(p); \
2007 do_oop; \
2008 ++p; \
2009 } \
2010 }
2011
2012
2013 // The following macros call specialized macros, passing either oop or
2014 // narrowOop as the specialization type. These test the UseCompressedOops
2015 // flag.
2016 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2017 { \
2018 /* Compute oopmap block range. The common case \
2019 is nonstatic_oop_map_size == 1. */ \
2020 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2021 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2022 if (UseCompressedOops) { \
2023 while (map < end_map) { \
2024 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2025 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2026 do_oop, assert_fn) \
2027 ++map; \
2028 } \
2029 } else { \
2030 while (map < end_map) { \
2031 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2032 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2033 do_oop, assert_fn) \
2034 ++map; \
2035 } \
2036 } \
2037 }
2038
2039 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2040 { \
2041 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2042 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2043 if (UseCompressedOops) { \
2044 while (start_map < map) { \
2045 --map; \
2046 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2047 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2048 do_oop, assert_fn) \
2049 } \
2050 } else { \
2051 while (start_map < map) { \
2052 --map; \
2053 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2054 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2055 do_oop, assert_fn) \
2056 } \
2057 } \
2058 }
2059
2060 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2061 assert_fn) \
2062 { \
2063 /* Compute oopmap block range. The common case is \
2064 nonstatic_oop_map_size == 1, so we accept the \
2065 usually non-existent extra overhead of examining \
2066 all the maps. */ \
2067 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2068 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2069 if (UseCompressedOops) { \
2070 while (map < end_map) { \
2071 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2072 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2073 low, high, \
2074 do_oop, assert_fn) \
2075 ++map; \
2076 } \
2077 } else { \
2078 while (map < end_map) { \
2079 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2080 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2081 low, high, \
2082 do_oop, assert_fn) \
2083 ++map; \
2084 } \
2085 } \
2086 }
2087
2088 void InstanceKlass::oop_follow_contents(oop obj) {
2089 assert(obj != NULL, "can't follow the content of NULL object");
2090 MarkSweep::follow_klass(obj->klass());
2091 InstanceKlass_OOP_MAP_ITERATE( \
2092 obj, \
2093 MarkSweep::mark_and_push(p), \
2094 assert_is_in_closed_subset)
2095 }
2096
2097 #if INCLUDE_ALL_GCS
2098 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2099 oop obj) {
2100 assert(obj != NULL, "can't follow the content of NULL object");
2101 PSParallelCompact::follow_klass(cm, obj->klass());
2102 // Only mark the header and let the scan of the meta-data mark
2103 // everything else.
2104 InstanceKlass_OOP_MAP_ITERATE( \
2105 obj, \
2106 PSParallelCompact::mark_and_push(cm, p), \
2107 assert_is_in)
2108 }
2109 #endif // INCLUDE_ALL_GCS
2110
2111 // closure's do_metadata() method dictates whether the given closure should be
2112 // applied to the klass ptr in the object header.
2113
2114 #define if_do_metadata_checked(closure, nv_suffix) \
2115 /* Make sure the non-virtual and the virtual versions match. */ \
2116 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2117 "Inconsistency in do_metadata"); \
2118 if (closure->do_metadata##nv_suffix())
2119
2120 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2121 \
2122 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2123 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2124 /* header */ \
2125 if_do_metadata_checked(closure, nv_suffix) { \
2126 closure->do_klass##nv_suffix(obj->klass()); \
2127 } \
2128 InstanceKlass_OOP_MAP_ITERATE( \
2129 obj, \
2130 SpecializationStats:: \
2131 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2132 (closure)->do_oop##nv_suffix(p), \
2133 assert_is_in_closed_subset) \
2134 return size_helper(); \
2135 }
2136
2137 #if INCLUDE_ALL_GCS
2138 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2139 \
2140 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2141 OopClosureType* closure) { \
2142 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2143 /* header */ \
2144 if_do_metadata_checked(closure, nv_suffix) { \
2145 closure->do_klass##nv_suffix(obj->klass()); \
2146 } \
2147 /* instance variables */ \
2148 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2149 obj, \
2150 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2151 (closure)->do_oop##nv_suffix(p), \
2152 assert_is_in_closed_subset) \
2153 return size_helper(); \
2154 }
2155 #endif // INCLUDE_ALL_GCS
2156
2157 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2158 \
2159 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2160 OopClosureType* closure, \
2161 MemRegion mr) { \
2162 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2163 if_do_metadata_checked(closure, nv_suffix) { \
2164 if (mr.contains(obj)) { \
2165 closure->do_klass##nv_suffix(obj->klass()); \
2166 } \
2167 } \
2168 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2169 obj, mr.start(), mr.end(), \
2170 (closure)->do_oop##nv_suffix(p), \
2171 assert_is_in_closed_subset) \
2172 return size_helper(); \
2173 }
2174
2175 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2176 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2177 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2178 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2179 #if INCLUDE_ALL_GCS
2180 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2181 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2182 #endif // INCLUDE_ALL_GCS
2183
2184 int InstanceKlass::oop_adjust_pointers(oop obj) {
2185 int size = size_helper();
2186 InstanceKlass_OOP_MAP_ITERATE( \
2187 obj, \
2188 MarkSweep::adjust_pointer(p), \
2189 assert_is_in)
2190 return size;
2191 }
2192
2193 #if INCLUDE_ALL_GCS
2194 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2195 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2196 obj, \
2197 if (PSScavenge::should_scavenge(p)) { \
2198 pm->claim_or_forward_depth(p); \
2199 }, \
2200 assert_nothing )
2201 }
2202
2203 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2204 int size = size_helper();
2205 InstanceKlass_OOP_MAP_ITERATE( \
2206 obj, \
2207 PSParallelCompact::adjust_pointer(p), \
2208 assert_is_in)
2209 obj->update_header(cm);
2210 return size;
2211 }
2212
2213 #endif // INCLUDE_ALL_GCS
2214
2215 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2216 assert(is_loader_alive(is_alive), "this klass should be live");
2217 if (is_interface()) {
2218 if (ClassUnloading) {
2219 Klass* impl = implementor();
2220 if (impl != NULL) {
2221 if (!impl->is_loader_alive(is_alive)) {
2222 // remove this guy
2223 Klass** klass = adr_implementor();
2224 assert(klass != NULL, "null klass");
2225 if (klass != NULL) {
2226 *klass = NULL;
2227 }
2228 }
2229 }
2230 }
2231 }
2232 }
2233
2234 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2235 for (int m = 0; m < methods()->length(); m++) {
2236 MethodData* mdo = methods()->at(m)->method_data();
2237 if (mdo != NULL) {
2238 for (ProfileData* data = mdo->first_data();
2239 mdo->is_valid(data);
2240 data = mdo->next_data(data)) {
2241 data->clean_weak_klass_links(is_alive);
2242 }
2243 ParametersTypeData* parameters = mdo->parameters_type_data();
2244 if (parameters != NULL) {
2245 parameters->clean_weak_klass_links(is_alive);
2246 }
2247 }
2248 }
2249 }
2250
2251
2252 static void remove_unshareable_in_class(Klass* k) {
2253 // remove klass's unshareable info
2254 k->remove_unshareable_info();
2255 }
2256
2257 void InstanceKlass::remove_unshareable_info() {
2258 Klass::remove_unshareable_info();
2259 // Unlink the class
2260 if (is_linked()) {
2261 unlink_class();
2262 }
2263 init_implementor();
2264
2265 constants()->remove_unshareable_info();
2266
2267 for (int i = 0; i < methods()->length(); i++) {
2268 Method* m = methods()->at(i);
2269 m->remove_unshareable_info();
2270 }
2271
2272 // do array classes also.
2273 array_klasses_do(remove_unshareable_in_class);
2274 }
2275
2276 void restore_unshareable_in_class(Klass* k, TRAPS) {
2277 k->restore_unshareable_info(CHECK);
2278 }
2279
2280 void InstanceKlass::restore_unshareable_info(TRAPS) {
2281 Klass::restore_unshareable_info(CHECK);
2282 instanceKlassHandle ik(THREAD, this);
2283
2284 Array<Method*>* methods = ik->methods();
2285 int num_methods = methods->length();
2286 for (int index2 = 0; index2 < num_methods; ++index2) {
2287 methodHandle m(THREAD, methods->at(index2));
2288 m()->link_method(m, CHECK);
2289 // restore method's vtable by calling a virtual function
2290 m->restore_vtable();
2291 }
2292 if (JvmtiExport::has_redefined_a_class()) {
2293 // Reinitialize vtable because RedefineClasses may have changed some
2294 // entries in this vtable for super classes so the CDS vtable might
2295 // point to old or obsolete entries. RedefineClasses doesn't fix up
2296 // vtables in the shared system dictionary, only the main one.
2297 // It also redefines the itable too so fix that too.
2298 ResourceMark rm(THREAD);
2299 ik->vtable()->initialize_vtable(false, CHECK);
2300 ik->itable()->initialize_itable(false, CHECK);
2301 }
2302
2303 // restore constant pool resolved references
2304 ik->constants()->restore_unshareable_info(CHECK);
2305
2306 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2307 }
2308
2309 static void clear_all_breakpoints(Method* m) {
2310 m->clear_all_breakpoints();
2311 }
2312
2313
2314 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2315 // notify the debugger
2316 if (JvmtiExport::should_post_class_unload()) {
2317 JvmtiExport::post_class_unload(ik);
2318 }
2319
2320 // notify ClassLoadingService of class unload
2321 ClassLoadingService::notify_class_unloaded(ik);
2322 }
2323
2324 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2325 // Clean up C heap
2326 ik->release_C_heap_structures();
2327 ik->constants()->release_C_heap_structures();
2328 }
2329
2330 void InstanceKlass::release_C_heap_structures() {
2331
2332 // Can't release the constant pool here because the constant pool can be
2333 // deallocated separately from the InstanceKlass for default methods and
2334 // redefine classes.
2335
2336 // Deallocate oop map cache
2337 if (_oop_map_cache != NULL) {
2338 delete _oop_map_cache;
2339 _oop_map_cache = NULL;
2340 }
2341
2342 // Deallocate JNI identifiers for jfieldIDs
2343 JNIid::deallocate(jni_ids());
2344 set_jni_ids(NULL);
2345
2346 jmethodID* jmeths = methods_jmethod_ids_acquire();
2347 if (jmeths != (jmethodID*)NULL) {
2348 release_set_methods_jmethod_ids(NULL);
2349 FreeHeap(jmeths);
2350 }
2351
2352 // Deallocate MemberNameTable
2353 {
2354 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2355 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2356 MemberNameTable* mnt = member_names();
2357 if (mnt != NULL) {
2358 delete mnt;
2359 set_member_names(NULL);
2360 }
2361 }
2362
2363 // release dependencies
2364 nmethodBucket* b = _dependencies;
2365 _dependencies = NULL;
2366 while (b != NULL) {
2367 nmethodBucket* next = b->next();
2368 delete b;
2369 b = next;
2370 }
2371
2372 // Deallocate breakpoint records
2373 if (breakpoints() != 0x0) {
2374 methods_do(clear_all_breakpoints);
2375 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2376 }
2377
2378 // deallocate information about previous versions
2379 if (_previous_versions != NULL) {
2380 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2381 PreviousVersionNode * pv_node = _previous_versions->at(i);
2382 delete pv_node;
2383 }
2384 delete _previous_versions;
2385 _previous_versions = NULL;
2386 }
2387
2388 // deallocate the cached class file
2389 if (_cached_class_file != NULL) {
2390 os::free(_cached_class_file, mtClass);
2391 _cached_class_file = NULL;
2392 }
2393
2394 // Decrement symbol reference counts associated with the unloaded class.
2395 if (_name != NULL) _name->decrement_refcount();
2396 // unreference array name derived from this class name (arrays of an unloaded
2397 // class can't be referenced anymore).
2398 if (_array_name != NULL) _array_name->decrement_refcount();
2399 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2400
2401 assert(_total_instanceKlass_count >= 1, "Sanity check");
2402 Atomic::dec(&_total_instanceKlass_count);
2403 }
2404
2405 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2406 if (array == NULL) {
2407 _source_debug_extension = NULL;
2408 } else {
2409 // Adding one to the attribute length in order to store a null terminator
2410 // character could cause an overflow because the attribute length is
2411 // already coded with an u4 in the classfile, but in practice, it's
2412 // unlikely to happen.
2413 assert((length+1) > length, "Overflow checking");
2414 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2415 for (int i = 0; i < length; i++) {
2416 sde[i] = array[i];
2417 }
2418 sde[length] = '\0';
2419 _source_debug_extension = sde;
2420 }
2421 }
2422
2423 address InstanceKlass::static_field_addr(int offset) {
2424 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2425 }
2426
2427
2428 const char* InstanceKlass::signature_name() const {
2429 int hash_len = 0;
2430 char hash_buf[40];
2431
2432 // If this is an anonymous class, append a hash to make the name unique
2433 if (is_anonymous()) {
2434 assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
2435 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2436 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2437 hash_len = (int)strlen(hash_buf);
2438 }
2439
2440 // Get the internal name as a c string
2441 const char* src = (const char*) (name()->as_C_string());
2442 const int src_length = (int)strlen(src);
2443
2444 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2445
2446 // Add L as type indicator
2447 int dest_index = 0;
2448 dest[dest_index++] = 'L';
2449
2450 // Add the actual class name
2451 for (int src_index = 0; src_index < src_length; ) {
2452 dest[dest_index++] = src[src_index++];
2453 }
2454
2455 // If we have a hash, append it
2456 for (int hash_index = 0; hash_index < hash_len; ) {
2457 dest[dest_index++] = hash_buf[hash_index++];
2458 }
2459
2460 // Add the semicolon and the NULL
2461 dest[dest_index++] = ';';
2462 dest[dest_index] = '\0';
2463 return dest;
2464 }
2465
2466 // different verisons of is_same_class_package
2467 bool InstanceKlass::is_same_class_package(Klass* class2) {
2468 Klass* class1 = this;
2469 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2470 Symbol* classname1 = class1->name();
2471
2472 if (class2->oop_is_objArray()) {
2473 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2474 }
2475 oop classloader2;
2476 if (class2->oop_is_instance()) {
2477 classloader2 = InstanceKlass::cast(class2)->class_loader();
2478 } else {
2479 assert(class2->oop_is_typeArray(), "should be type array");
2480 classloader2 = NULL;
2481 }
2482 Symbol* classname2 = class2->name();
2483
2484 return InstanceKlass::is_same_class_package(classloader1, classname1,
2485 classloader2, classname2);
2486 }
2487
2488 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2489 Klass* class1 = this;
2490 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2491 Symbol* classname1 = class1->name();
2492
2493 return InstanceKlass::is_same_class_package(classloader1, classname1,
2494 classloader2, classname2);
2495 }
2496
2497 // return true if two classes are in the same package, classloader
2498 // and classname information is enough to determine a class's package
2499 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2500 oop class_loader2, Symbol* class_name2) {
2501 if (class_loader1 != class_loader2) {
2502 return false;
2503 } else if (class_name1 == class_name2) {
2504 return true; // skip painful bytewise comparison
2505 } else {
2506 ResourceMark rm;
2507
2508 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2509 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2510 // Otherwise, we just compare jbyte values between the strings.
2511 const jbyte *name1 = class_name1->base();
2512 const jbyte *name2 = class_name2->base();
2513
2514 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2515 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2516
2517 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2518 // One of the two doesn't have a package. Only return true
2519 // if the other one also doesn't have a package.
2520 return last_slash1 == last_slash2;
2521 } else {
2522 // Skip over '['s
2523 if (*name1 == '[') {
2524 do {
2525 name1++;
2526 } while (*name1 == '[');
2527 if (*name1 != 'L') {
2528 // Something is terribly wrong. Shouldn't be here.
2529 return false;
2530 }
2531 }
2532 if (*name2 == '[') {
2533 do {
2534 name2++;
2535 } while (*name2 == '[');
2536 if (*name2 != 'L') {
2537 // Something is terribly wrong. Shouldn't be here.
2538 return false;
2539 }
2540 }
2541
2542 // Check that package part is identical
2543 int length1 = last_slash1 - name1;
2544 int length2 = last_slash2 - name2;
2545
2546 return UTF8::equal(name1, length1, name2, length2);
2547 }
2548 }
2549 }
2550
2551 // Returns true iff super_method can be overridden by a method in targetclassname
2552 // See JSL 3rd edition 8.4.6.1
2553 // Assumes name-signature match
2554 // "this" is InstanceKlass of super_method which must exist
2555 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2556 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2557 // Private methods can not be overridden
2558 if (super_method->is_private()) {
2559 return false;
2560 }
2561 // If super method is accessible, then override
2562 if ((super_method->is_protected()) ||
2563 (super_method->is_public())) {
2564 return true;
2565 }
2566 // Package-private methods are not inherited outside of package
2567 assert(super_method->is_package_private(), "must be package private");
2568 return(is_same_class_package(targetclassloader(), targetclassname));
2569 }
2570
2571 /* defined for now in jvm.cpp, for historical reasons *--
2572 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2573 Symbol*& simple_name_result, TRAPS) {
2574 ...
2575 }
2576 */
2577
2578 // tell if two classes have the same enclosing class (at package level)
2579 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2580 Klass* class2_oop, TRAPS) {
2581 if (class2_oop == class1()) return true;
2582 if (!class2_oop->oop_is_instance()) return false;
2583 instanceKlassHandle class2(THREAD, class2_oop);
2584
2585 // must be in same package before we try anything else
2586 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2587 return false;
2588
2589 // As long as there is an outer1.getEnclosingClass,
2590 // shift the search outward.
2591 instanceKlassHandle outer1 = class1;
2592 for (;;) {
2593 // As we walk along, look for equalities between outer1 and class2.
2594 // Eventually, the walks will terminate as outer1 stops
2595 // at the top-level class around the original class.
2596 bool ignore_inner_is_member;
2597 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2598 CHECK_false);
2599 if (next == NULL) break;
2600 if (next == class2()) return true;
2601 outer1 = instanceKlassHandle(THREAD, next);
2602 }
2603
2604 // Now do the same for class2.
2605 instanceKlassHandle outer2 = class2;
2606 for (;;) {
2607 bool ignore_inner_is_member;
2608 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2609 CHECK_false);
2610 if (next == NULL) break;
2611 // Might as well check the new outer against all available values.
2612 if (next == class1()) return true;
2613 if (next == outer1()) return true;
2614 outer2 = instanceKlassHandle(THREAD, next);
2615 }
2616
2617 // If by this point we have not found an equality between the
2618 // two classes, we know they are in separate package members.
2619 return false;
2620 }
2621
2622
2623 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2624 jint access = access_flags().as_int();
2625
2626 // But check if it happens to be member class.
2627 instanceKlassHandle ik(THREAD, this);
2628 InnerClassesIterator iter(ik);
2629 for (; !iter.done(); iter.next()) {
2630 int ioff = iter.inner_class_info_index();
2631 // Inner class attribute can be zero, skip it.
2632 // Strange but true: JVM spec. allows null inner class refs.
2633 if (ioff == 0) continue;
2634
2635 // only look at classes that are already loaded
2636 // since we are looking for the flags for our self.
2637 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2638 if ((ik->name() == inner_name)) {
2639 // This is really a member class.
2640 access = iter.inner_access_flags();
2641 break;
2642 }
2643 }
2644 // Remember to strip ACC_SUPER bit
2645 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2646 }
2647
2648 jint InstanceKlass::jvmti_class_status() const {
2649 jint result = 0;
2650
2651 if (is_linked()) {
2652 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2653 }
2654
2655 if (is_initialized()) {
2656 assert(is_linked(), "Class status is not consistent");
2657 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2658 }
2659 if (is_in_error_state()) {
2660 result |= JVMTI_CLASS_STATUS_ERROR;
2661 }
2662 return result;
2663 }
2664
2665 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2666 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2667 int method_table_offset_in_words = ioe->offset()/wordSize;
2668 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2669 / itableOffsetEntry::size();
2670
2671 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2672 // If the interface isn't implemented by the receiver class,
2673 // the VM should throw IncompatibleClassChangeError.
2674 if (cnt >= nof_interfaces) {
2675 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2676 }
2677
2678 Klass* ik = ioe->interface_klass();
2679 if (ik == holder) break;
2680 }
2681
2682 itableMethodEntry* ime = ioe->first_method_entry(this);
2683 Method* m = ime[index].method();
2684 if (m == NULL) {
2685 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2686 }
2687 return m;
2688 }
2689
2690
2691 #if INCLUDE_JVMTI
2692 // update default_methods for redefineclasses for methods that are
2693 // not yet in the vtable due to concurrent subclass define and superinterface
2694 // redefinition
2695 // Note: those in the vtable, should have been updated via adjust_method_entries
2696 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2697 int methods_length, bool* trace_name_printed) {
2698 // search the default_methods for uses of either obsolete or EMCP methods
2699 if (default_methods() != NULL) {
2700 for (int j = 0; j < methods_length; j++) {
2701 Method* old_method = old_methods[j];
2702 Method* new_method = new_methods[j];
2703
2704 for (int index = 0; index < default_methods()->length(); index ++) {
2705 if (default_methods()->at(index) == old_method) {
2706 default_methods()->at_put(index, new_method);
2707 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2708 if (!(*trace_name_printed)) {
2709 // RC_TRACE_MESG macro has an embedded ResourceMark
2710 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2711 external_name(),
2712 old_method->method_holder()->external_name()));
2713 *trace_name_printed = true;
2714 }
2715 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2716 new_method->name()->as_C_string(),
2717 new_method->signature()->as_C_string()));
2718 }
2719 }
2720 }
2721 }
2722 }
2723 }
2724 #endif // INCLUDE_JVMTI
2725
2726 // On-stack replacement stuff
2727 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2728 // only one compilation can be active
2729 NEEDS_CLEANUP
2730 // This is a short non-blocking critical region, so the no safepoint check is ok.
2731 OsrList_lock->lock_without_safepoint_check();
2732 assert(n->is_osr_method(), "wrong kind of nmethod");
2733 n->set_osr_link(osr_nmethods_head());
2734 set_osr_nmethods_head(n);
2735 // Raise the highest osr level if necessary
2736 if (TieredCompilation) {
2737 Method* m = n->method();
2738 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2739 }
2740 // Remember to unlock again
2741 OsrList_lock->unlock();
2742
2743 // Get rid of the osr methods for the same bci that have lower levels.
2744 if (TieredCompilation) {
2745 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2746 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2747 if (inv != NULL && inv->is_in_use()) {
2748 inv->make_not_entrant();
2749 }
2750 }
2751 }
2752 }
2753
2754
2755 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2756 // This is a short non-blocking critical region, so the no safepoint check is ok.
2757 OsrList_lock->lock_without_safepoint_check();
2758 assert(n->is_osr_method(), "wrong kind of nmethod");
2759 nmethod* last = NULL;
2760 nmethod* cur = osr_nmethods_head();
2761 int max_level = CompLevel_none; // Find the max comp level excluding n
2762 Method* m = n->method();
2763 // Search for match
2764 while(cur != NULL && cur != n) {
2765 if (TieredCompilation) {
2766 // Find max level before n
2767 max_level = MAX2(max_level, cur->comp_level());
2768 }
2769 last = cur;
2770 cur = cur->osr_link();
2771 }
2772 nmethod* next = NULL;
2773 if (cur == n) {
2774 next = cur->osr_link();
2775 if (last == NULL) {
2776 // Remove first element
2777 set_osr_nmethods_head(next);
2778 } else {
2779 last->set_osr_link(next);
2780 }
2781 }
2782 n->set_osr_link(NULL);
2783 if (TieredCompilation) {
2784 cur = next;
2785 while (cur != NULL) {
2786 // Find max level after n
2787 max_level = MAX2(max_level, cur->comp_level());
2788 cur = cur->osr_link();
2789 }
2790 m->set_highest_osr_comp_level(max_level);
2791 }
2792 // Remember to unlock again
2793 OsrList_lock->unlock();
2794 }
2795
2796 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2797 // This is a short non-blocking critical region, so the no safepoint check is ok.
2798 OsrList_lock->lock_without_safepoint_check();
2799 nmethod* osr = osr_nmethods_head();
2800 nmethod* best = NULL;
2801 while (osr != NULL) {
2802 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2803 // There can be a time when a c1 osr method exists but we are waiting
2804 // for a c2 version. When c2 completes its osr nmethod we will trash
2805 // the c1 version and only be able to find the c2 version. However
2806 // while we overflow in the c1 code at back branches we don't want to
2807 // try and switch to the same code as we are already running
2808
2809 if (osr->method() == m &&
2810 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2811 if (match_level) {
2812 if (osr->comp_level() == comp_level) {
2813 // Found a match - return it.
2814 OsrList_lock->unlock();
2815 return osr;
2816 }
2817 } else {
2818 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2819 if (osr->comp_level() == CompLevel_highest_tier) {
2820 // Found the best possible - return it.
2821 OsrList_lock->unlock();
2822 return osr;
2823 }
2824 best = osr;
2825 }
2826 }
2827 }
2828 osr = osr->osr_link();
2829 }
2830 OsrList_lock->unlock();
2831 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2832 return best;
2833 }
2834 return NULL;
2835 }
2836
2837 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2838 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2839 MutexLocker ml(MemberNameTable_lock);
2840 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2841 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2842
2843 if (_member_names == NULL) {
2844 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2845 }
2846 _member_names->add_member_name(index, mem_name_wref);
2847 }
2848
2849 oop InstanceKlass::get_member_name(int index) {
2850 MutexLocker ml(MemberNameTable_lock);
2851 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2852 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2853
2854 if (_member_names == NULL) {
2855 return NULL;
2856 }
2857 oop mem_name =_member_names->get_member_name(index);
2858 return mem_name;
2859 }
2860
2861 // -----------------------------------------------------------------------------------------------------
2862 // Printing
2863
2864 #ifndef PRODUCT
2865
2866 #define BULLET " - "
2867
2868 static const char* state_names[] = {
2869 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2870 };
2871
2872 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2873 for (int i = 0; i < len; i++) {
2874 intptr_t e = start[i];
2875 st->print("%d : " INTPTR_FORMAT, i, e);
2876 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2877 st->print(" ");
2878 ((Metadata*)e)->print_value_on(st);
2879 }
2880 st->cr();
2881 }
2882 }
2883
2884 void InstanceKlass::print_on(outputStream* st) const {
2885 assert(is_klass(), "must be klass");
2886 Klass::print_on(st);
2887
2888 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2889 st->print(BULLET"klass size: %d", size()); st->cr();
2890 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2891 st->print(BULLET"state: "); st->print_cr(state_names[_init_state]);
2892 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2893 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2894 st->print(BULLET"sub: ");
2895 Klass* sub = subklass();
2896 int n;
2897 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2898 if (n < MaxSubklassPrintSize) {
2899 sub->print_value_on(st);
2900 st->print(" ");
2901 }
2902 }
2903 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2904 st->cr();
2905
2906 if (is_interface()) {
2907 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2908 if (nof_implementors() == 1) {
2909 st->print_cr(BULLET"implementor: ");
2910 st->print(" ");
2911 implementor()->print_value_on(st);
2912 st->cr();
2913 }
2914 }
2915
2916 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2917 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2918 if (Verbose || WizardMode) {
2919 Array<Method*>* method_array = methods();
2920 for (int i = 0; i < method_array->length(); i++) {
2921 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2922 }
2923 }
2924 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2925 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2926 if (Verbose && default_methods() != NULL) {
2927 Array<Method*>* method_array = default_methods();
2928 for (int i = 0; i < method_array->length(); i++) {
2929 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2930 }
2931 }
2932 if (default_vtable_indices() != NULL) {
2933 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2934 }
2935 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2936 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2937 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2938 if (class_loader_data() != NULL) {
2939 st->print(BULLET"class loader data: ");
2940 class_loader_data()->print_value_on(st);
2941 st->cr();
2942 }
2943 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2944 if (source_file_name() != NULL) {
2945 st->print(BULLET"source file: ");
2946 source_file_name()->print_value_on(st);
2947 st->cr();
2948 }
2949 if (source_debug_extension() != NULL) {
2950 st->print(BULLET"source debug extension: ");
2951 st->print("%s", source_debug_extension());
2952 st->cr();
2953 }
2954 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2955 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2956 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2957 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2958 {
2959 bool have_pv = false;
2960 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
2961 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
2962 pv_node != NULL; pv_node = pvw.next_previous_version()) {
2963 if (!have_pv)
2964 st->print(BULLET"previous version: ");
2965 have_pv = true;
2966 pv_node->prev_constant_pool()->print_value_on(st);
2967 }
2968 if (have_pv) st->cr();
2969 } // pvw is cleaned up
2970
2971 if (generic_signature() != NULL) {
2972 st->print(BULLET"generic signature: ");
2973 generic_signature()->print_value_on(st);
2974 st->cr();
2975 }
2976 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2977 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2978 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2979 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2980 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2981 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2982 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2983 FieldPrinter print_static_field(st);
2984 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2985 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2986 FieldPrinter print_nonstatic_field(st);
2987 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2988
2989 st->print(BULLET"non-static oop maps: ");
2990 OopMapBlock* map = start_of_nonstatic_oop_maps();
2991 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2992 while (map < end_map) {
2993 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2994 map++;
2995 }
2996 st->cr();
2997 }
2998
2999 #endif //PRODUCT
3000
3001 void InstanceKlass::print_value_on(outputStream* st) const {
3002 assert(is_klass(), "must be klass");
3003 if (Verbose || WizardMode) access_flags().print_on(st);
3004 name()->print_value_on(st);
3005 }
3006
3007 #ifndef PRODUCT
3008
3009 void FieldPrinter::do_field(fieldDescriptor* fd) {
3010 _st->print(BULLET);
3011 if (_obj == NULL) {
3012 fd->print_on(_st);
3013 _st->cr();
3014 } else {
3015 fd->print_on_for(_st, _obj);
3016 _st->cr();
3017 }
3018 }
3019
3020
3021 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3022 Klass::oop_print_on(obj, st);
3023
3024 if (this == SystemDictionary::String_klass()) {
3025 typeArrayOop value = java_lang_String::value(obj);
3026 juint offset = java_lang_String::offset(obj);
3027 juint length = java_lang_String::length(obj);
3028 if (value != NULL &&
3029 value->is_typeArray() &&
3030 offset <= (juint) value->length() &&
3031 offset + length <= (juint) value->length()) {
3032 st->print(BULLET"string: ");
3033 Handle h_obj(obj);
3034 java_lang_String::print(h_obj, st);
3035 st->cr();
3036 if (!WizardMode) return; // that is enough
3037 }
3038 }
3039
3040 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3041 FieldPrinter print_field(st, obj);
3042 do_nonstatic_fields(&print_field);
3043
3044 if (this == SystemDictionary::Class_klass()) {
3045 st->print(BULLET"signature: ");
3046 java_lang_Class::print_signature(obj, st);
3047 st->cr();
3048 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3049 st->print(BULLET"fake entry for mirror: ");
3050 mirrored_klass->print_value_on_maybe_null(st);
3051 st->cr();
3052 Klass* array_klass = java_lang_Class::array_klass(obj);
3053 st->print(BULLET"fake entry for array: ");
3054 array_klass->print_value_on_maybe_null(st);
3055 st->cr();
3056 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3057 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3058 Klass* real_klass = java_lang_Class::as_Klass(obj);
3059 if (real_klass != NULL && real_klass->oop_is_instance()) {
3060 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3061 }
3062 } else if (this == SystemDictionary::MethodType_klass()) {
3063 st->print(BULLET"signature: ");
3064 java_lang_invoke_MethodType::print_signature(obj, st);
3065 st->cr();
3066 }
3067 }
3068
3069 #endif //PRODUCT
3070
3071 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3072 st->print("a ");
3073 name()->print_value_on(st);
3074 obj->print_address_on(st);
3075 if (this == SystemDictionary::String_klass()
3076 && java_lang_String::value(obj) != NULL) {
3077 ResourceMark rm;
3078 int len = java_lang_String::length(obj);
3079 int plen = (len < 24 ? len : 12);
3080 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3081 st->print(" = \"%s\"", str);
3082 if (len > plen)
3083 st->print("...[%d]", len);
3084 } else if (this == SystemDictionary::Class_klass()) {
3085 Klass* k = java_lang_Class::as_Klass(obj);
3086 st->print(" = ");
3087 if (k != NULL) {
3088 k->print_value_on(st);
3089 } else {
3090 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3091 st->print("%s", tname ? tname : "type?");
3092 }
3093 } else if (this == SystemDictionary::MethodType_klass()) {
3094 st->print(" = ");
3095 java_lang_invoke_MethodType::print_signature(obj, st);
3096 } else if (java_lang_boxing_object::is_instance(obj)) {
3097 st->print(" = ");
3098 java_lang_boxing_object::print(obj, st);
3099 } else if (this == SystemDictionary::LambdaForm_klass()) {
3100 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3101 if (vmentry != NULL) {
3102 st->print(" => ");
3103 vmentry->print_value_on(st);
3104 }
3105 } else if (this == SystemDictionary::MemberName_klass()) {
3106 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3107 if (vmtarget != NULL) {
3108 st->print(" = ");
3109 vmtarget->print_value_on(st);
3110 } else {
3111 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3112 st->print(".");
3113 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3114 }
3115 }
3116 }
3117
3118 const char* InstanceKlass::internal_name() const {
3119 return external_name();
3120 }
3121
3122 #if INCLUDE_SERVICES
3123 // Size Statistics
3124 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3125 Klass::collect_statistics(sz);
3126
3127 sz->_inst_size = HeapWordSize * size_helper();
3128 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3129 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3130 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3131 ((is_interface() || is_anonymous()) ?
3132 align_object_offset(nonstatic_oop_map_size()) :
3133 nonstatic_oop_map_size());
3134
3135 int n = 0;
3136 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3137 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3138 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3139 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3140 n += (sz->_fields_bytes = sz->count_array(fields()));
3141 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3142 sz->_ro_bytes += n;
3143
3144 const ConstantPool* cp = constants();
3145 if (cp) {
3146 cp->collect_statistics(sz);
3147 }
3148
3149 const Annotations* anno = annotations();
3150 if (anno) {
3151 anno->collect_statistics(sz);
3152 }
3153
3154 const Array<Method*>* methods_array = methods();
3155 if (methods()) {
3156 for (int i = 0; i < methods_array->length(); i++) {
3157 Method* method = methods_array->at(i);
3158 if (method) {
3159 sz->_method_count ++;
3160 method->collect_statistics(sz);
3161 }
3162 }
3163 }
3164 }
3165 #endif // INCLUDE_SERVICES
3166
3167 // Verification
3168
3169 class VerifyFieldClosure: public OopClosure {
3170 protected:
3171 template <class T> void do_oop_work(T* p) {
3172 oop obj = oopDesc::load_decode_heap_oop(p);
3173 if (!obj->is_oop_or_null()) {
3174 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3175 Universe::print();
3176 guarantee(false, "boom");
3177 }
3178 }
3179 public:
3180 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3181 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3182 };
3183
3184 void InstanceKlass::verify_on(outputStream* st, bool check_dictionary) {
3185 #ifndef PRODUCT
3186 // Avoid redundant verifies, this really should be in product.
3187 if (_verify_count == Universe::verify_count()) return;
3188 _verify_count = Universe::verify_count();
3189 #endif
3190
3191 // Verify Klass
3192 Klass::verify_on(st, check_dictionary);
3193
3194 // Verify that klass is present in SystemDictionary if not already
3195 // verifying the SystemDictionary.
3196 if (is_loaded() && !is_anonymous() && check_dictionary) {
3197 Symbol* h_name = name();
3198 SystemDictionary::verify_obj_klass_present(h_name, class_loader_data());
3199 }
3200
3201 // Verify vtables
3202 if (is_linked()) {
3203 ResourceMark rm;
3204 // $$$ This used to be done only for m/s collections. Doing it
3205 // always seemed a valid generalization. (DLD -- 6/00)
3206 vtable()->verify(st);
3207 }
3208
3209 // Verify first subklass
3210 if (subklass_oop() != NULL) {
3211 guarantee(subklass_oop()->is_klass(), "should be klass");
3212 }
3213
3214 // Verify siblings
3215 Klass* super = this->super();
3216 Klass* sib = next_sibling();
3217 if (sib != NULL) {
3218 if (sib == this) {
3219 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3220 }
3221
3222 guarantee(sib->is_klass(), "should be klass");
3223 guarantee(sib->super() == super, "siblings should have same superklass");
3224 }
3225
3226 // Verify implementor fields
3227 Klass* im = implementor();
3228 if (im != NULL) {
3229 guarantee(is_interface(), "only interfaces should have implementor set");
3230 guarantee(im->is_klass(), "should be klass");
3231 guarantee(!im->is_interface() || im == this,
3232 "implementors cannot be interfaces");
3233 }
3234
3235 // Verify local interfaces
3236 if (local_interfaces()) {
3237 Array<Klass*>* local_interfaces = this->local_interfaces();
3238 for (int j = 0; j < local_interfaces->length(); j++) {
3239 Klass* e = local_interfaces->at(j);
3240 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3241 }
3242 }
3243
3244 // Verify transitive interfaces
3245 if (transitive_interfaces() != NULL) {
3246 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3247 for (int j = 0; j < transitive_interfaces->length(); j++) {
3248 Klass* e = transitive_interfaces->at(j);
3249 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3250 }
3251 }
3252
3253 // Verify methods
3254 if (methods() != NULL) {
3255 Array<Method*>* methods = this->methods();
3256 for (int j = 0; j < methods->length(); j++) {
3257 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3258 }
3259 for (int j = 0; j < methods->length() - 1; j++) {
3260 Method* m1 = methods->at(j);
3261 Method* m2 = methods->at(j + 1);
3262 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3263 }
3264 }
3265
3266 // Verify method ordering
3267 if (method_ordering() != NULL) {
3268 Array<int>* method_ordering = this->method_ordering();
3269 int length = method_ordering->length();
3270 if (JvmtiExport::can_maintain_original_method_order() ||
3271 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3272 guarantee(length == methods()->length(), "invalid method ordering length");
3273 jlong sum = 0;
3274 for (int j = 0; j < length; j++) {
3275 int original_index = method_ordering->at(j);
3276 guarantee(original_index >= 0, "invalid method ordering index");
3277 guarantee(original_index < length, "invalid method ordering index");
3278 sum += original_index;
3279 }
3280 // Verify sum of indices 0,1,...,length-1
3281 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3282 } else {
3283 guarantee(length == 0, "invalid method ordering length");
3284 }
3285 }
3286
3287 // Verify default methods
3288 if (default_methods() != NULL) {
3289 Array<Method*>* methods = this->default_methods();
3290 for (int j = 0; j < methods->length(); j++) {
3291 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3292 }
3293 for (int j = 0; j < methods->length() - 1; j++) {
3294 Method* m1 = methods->at(j);
3295 Method* m2 = methods->at(j + 1);
3296 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3297 }
3298 }
3299
3300 // Verify JNI static field identifiers
3301 if (jni_ids() != NULL) {
3302 jni_ids()->verify(this);
3303 }
3304
3305 // Verify other fields
3306 if (array_klasses() != NULL) {
3307 guarantee(array_klasses()->is_klass(), "should be klass");
3308 }
3309 if (constants() != NULL) {
3310 guarantee(constants()->is_constantPool(), "should be constant pool");
3311 }
3312 const Klass* host = host_klass();
3313 if (host != NULL) {
3314 guarantee(host->is_klass(), "should be klass");
3315 }
3316 }
3317
3318 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3319 Klass::oop_verify_on(obj, st);
3320 VerifyFieldClosure blk;
3321 obj->oop_iterate_no_header(&blk);
3322 }
3323
3324
3325 // JNIid class for jfieldIDs only
3326 // Note to reviewers:
3327 // These JNI functions are just moved over to column 1 and not changed
3328 // in the compressed oops workspace.
3329 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3330 _holder = holder;
3331 _offset = offset;
3332 _next = next;
3333 debug_only(_is_static_field_id = false;)
3334 }
3335
3336
3337 JNIid* JNIid::find(int offset) {
3338 JNIid* current = this;
3339 while (current != NULL) {
3340 if (current->offset() == offset) return current;
3341 current = current->next();
3342 }
3343 return NULL;
3344 }
3345
3346 void JNIid::deallocate(JNIid* current) {
3347 while (current != NULL) {
3348 JNIid* next = current->next();
3349 delete current;
3350 current = next;
3351 }
3352 }
3353
3354
3355 void JNIid::verify(Klass* holder) {
3356 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3357 int end_field_offset;
3358 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3359
3360 JNIid* current = this;
3361 while (current != NULL) {
3362 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3363 #ifdef ASSERT
3364 int o = current->offset();
3365 if (current->is_static_field_id()) {
3366 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3367 }
3368 #endif
3369 current = current->next();
3370 }
3371 }
3372
3373
3374 #ifdef ASSERT
3375 void InstanceKlass::set_init_state(ClassState state) {
3376 bool good_state = is_shared() ? (_init_state <= state)
3377 : (_init_state < state);
3378 assert(good_state || state == allocated, "illegal state transition");
3379 _init_state = (u1)state;
3380 }
3381 #endif
3382
3383
3384 // RedefineClasses() support for previous versions:
3385
3386 // Purge previous versions
3387 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3388 if (ik->previous_versions() != NULL) {
3389 // This klass has previous versions so see what we can cleanup
3390 // while it is safe to do so.
3391
3392 int deleted_count = 0; // leave debugging breadcrumbs
3393 int live_count = 0;
3394 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3395 ClassLoaderData::the_null_class_loader_data() :
3396 ik->class_loader_data();
3397
3398 // RC_TRACE macro has an embedded ResourceMark
3399 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3400 ik->external_name(), ik->previous_versions()->length()));
3401
3402 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3403 // check the previous versions array
3404 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3405 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3406 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3407
3408 ConstantPool* pvcp = cp_ref;
3409 if (!pvcp->on_stack()) {
3410 // If the constant pool isn't on stack, none of the methods
3411 // are executing. Delete all the methods, the constant pool and
3412 // and this previous version node.
3413 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3414 if (method_refs != NULL) {
3415 for (int j = method_refs->length() - 1; j >= 0; j--) {
3416 Method* method = method_refs->at(j);
3417 assert(method != NULL, "method ref was unexpectedly cleared");
3418 method_refs->remove_at(j);
3419 // method will be freed with associated class.
3420 }
3421 }
3422 // Remove the constant pool
3423 delete pv_node;
3424 // Since we are traversing the array backwards, we don't have to
3425 // do anything special with the index.
3426 ik->previous_versions()->remove_at(i);
3427 deleted_count++;
3428 continue;
3429 } else {
3430 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3431 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3432 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3433 live_count++;
3434 }
3435
3436 // At least one method is live in this previous version, clean out
3437 // the others or mark them as obsolete.
3438 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3439 if (method_refs != NULL) {
3440 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3441 method_refs->length()));
3442 for (int j = method_refs->length() - 1; j >= 0; j--) {
3443 Method* method = method_refs->at(j);
3444 assert(method != NULL, "method ref was unexpectedly cleared");
3445
3446 // Remove the emcp method if it's not executing
3447 // If it's been made obsolete by a redefinition of a non-emcp
3448 // method, mark it as obsolete but leave it to clean up later.
3449 if (!method->on_stack()) {
3450 method_refs->remove_at(j);
3451 } else if (emcp_method_count == 0) {
3452 method->set_is_obsolete();
3453 } else {
3454 // RC_TRACE macro has an embedded ResourceMark
3455 RC_TRACE(0x00000200,
3456 ("purge: %s(%s): prev method @%d in version @%d is alive",
3457 method->name()->as_C_string(),
3458 method->signature()->as_C_string(), j, i));
3459 }
3460 }
3461 }
3462 }
3463 assert(ik->previous_versions()->length() == live_count, "sanity check");
3464 RC_TRACE(0x00000200,
3465 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3466 deleted_count));
3467 }
3468 }
3469
3470 // External interface for use during class unloading.
3471 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3472 // Call with >0 emcp methods since they are not currently being redefined.
3473 purge_previous_versions_internal(ik, 1);
3474 }
3475
3476
3477 // Potentially add an information node that contains pointers to the
3478 // interesting parts of the previous version of the_class.
3479 // This is also where we clean out any unused references.
3480 // Note that while we delete nodes from the _previous_versions
3481 // array, we never delete the array itself until the klass is
3482 // unloaded. The has_been_redefined() query depends on that fact.
3483 //
3484 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3485 BitMap* emcp_methods, int emcp_method_count) {
3486 assert(Thread::current()->is_VM_thread(),
3487 "only VMThread can add previous versions");
3488
3489 if (_previous_versions == NULL) {
3490 // This is the first previous version so make some space.
3491 // Start with 2 elements under the assumption that the class
3492 // won't be redefined much.
3493 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3494 GrowableArray<PreviousVersionNode *>(2, true);
3495 }
3496
3497 ConstantPool* cp_ref = ikh->constants();
3498
3499 // RC_TRACE macro has an embedded ResourceMark
3500 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3501 "on_stack=%d",
3502 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3503 cp_ref->on_stack()));
3504
3505 // If the constant pool for this previous version of the class
3506 // is not marked as being on the stack, then none of the methods
3507 // in this previous version of the class are on the stack so
3508 // we don't need to create a new PreviousVersionNode. However,
3509 // we still need to examine older previous versions below.
3510 Array<Method*>* old_methods = ikh->methods();
3511
3512 if (cp_ref->on_stack()) {
3513 PreviousVersionNode * pv_node = NULL;
3514 if (emcp_method_count == 0) {
3515 // non-shared ConstantPool gets a reference
3516 pv_node = new PreviousVersionNode(cp_ref, NULL);
3517 RC_TRACE(0x00000400,
3518 ("add: all methods are obsolete; flushing any EMCP refs"));
3519 } else {
3520 int local_count = 0;
3521 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3522 GrowableArray<Method*>(emcp_method_count, true);
3523 for (int i = 0; i < old_methods->length(); i++) {
3524 if (emcp_methods->at(i)) {
3525 // this old method is EMCP. Save it only if it's on the stack
3526 Method* old_method = old_methods->at(i);
3527 if (old_method->on_stack()) {
3528 method_refs->append(old_method);
3529 }
3530 if (++local_count >= emcp_method_count) {
3531 // no more EMCP methods so bail out now
3532 break;
3533 }
3534 }
3535 }
3536 // non-shared ConstantPool gets a reference
3537 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3538 }
3539 // append new previous version.
3540 _previous_versions->append(pv_node);
3541 }
3542
3543 // Since the caller is the VMThread and we are at a safepoint, this
3544 // is a good time to clear out unused references.
3545
3546 RC_TRACE(0x00000400, ("add: previous version length=%d",
3547 _previous_versions->length()));
3548
3549 // Purge previous versions not executing on the stack
3550 purge_previous_versions_internal(this, emcp_method_count);
3551
3552 int obsolete_method_count = old_methods->length() - emcp_method_count;
3553
3554 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3555 _previous_versions->length() > 0) {
3556 // We have a mix of obsolete and EMCP methods so we have to
3557 // clear out any matching EMCP method entries the hard way.
3558 int local_count = 0;
3559 for (int i = 0; i < old_methods->length(); i++) {
3560 if (!emcp_methods->at(i)) {
3561 // only obsolete methods are interesting
3562 Method* old_method = old_methods->at(i);
3563 Symbol* m_name = old_method->name();
3564 Symbol* m_signature = old_method->signature();
3565
3566 // we might not have added the last entry
3567 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3568 // check the previous versions array for non executing obsolete methods
3569 PreviousVersionNode * pv_node = _previous_versions->at(j);
3570
3571 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3572 if (method_refs == NULL) {
3573 // We have run into a PreviousVersion generation where
3574 // all methods were made obsolete during that generation's
3575 // RedefineClasses() operation. At the time of that
3576 // operation, all EMCP methods were flushed so we don't
3577 // have to go back any further.
3578 //
3579 // A NULL method_refs is different than an empty method_refs.
3580 // We cannot infer any optimizations about older generations
3581 // from an empty method_refs for the current generation.
3582 break;
3583 }
3584
3585 for (int k = method_refs->length() - 1; k >= 0; k--) {
3586 Method* method = method_refs->at(k);
3587
3588 if (!method->is_obsolete() &&
3589 method->name() == m_name &&
3590 method->signature() == m_signature) {
3591 // The current RedefineClasses() call has made all EMCP
3592 // versions of this method obsolete so mark it as obsolete
3593 // and remove the reference.
3594 RC_TRACE(0x00000400,
3595 ("add: %s(%s): flush obsolete method @%d in version @%d",
3596 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3597
3598 method->set_is_obsolete();
3599 // Leave obsolete methods on the previous version list to
3600 // clean up later.
3601 break;
3602 }
3603 }
3604
3605 // The previous loop may not find a matching EMCP method, but
3606 // that doesn't mean that we can optimize and not go any
3607 // further back in the PreviousVersion generations. The EMCP
3608 // method for this generation could have already been deleted,
3609 // but there still may be an older EMCP method that has not
3610 // been deleted.
3611 }
3612
3613 if (++local_count >= obsolete_method_count) {
3614 // no more obsolete methods so bail out now
3615 break;
3616 }
3617 }
3618 }
3619 }
3620 } // end add_previous_version()
3621
3622
3623 // Determine if InstanceKlass has a previous version.
3624 bool InstanceKlass::has_previous_version() const {
3625 return (_previous_versions != NULL && _previous_versions->length() > 0);
3626 } // end has_previous_version()
3627
3628
3629 Method* InstanceKlass::method_with_idnum(int idnum) {
3630 Method* m = NULL;
3631 if (idnum < methods()->length()) {
3632 m = methods()->at(idnum);
3633 }
3634 if (m == NULL || m->method_idnum() != idnum) {
3635 for (int index = 0; index < methods()->length(); ++index) {
3636 m = methods()->at(index);
3637 if (m->method_idnum() == idnum) {
3638 return m;
3639 }
3640 }
3641 // None found, return null for the caller to handle.
3642 return NULL;
3643 }
3644 return m;
3645 }
3646
3647 jint InstanceKlass::get_cached_class_file_len() {
3648 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3649 }
3650
3651 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3652 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3653 }
3654
3655
3656 // Construct a PreviousVersionNode entry for the array hung off
3657 // the InstanceKlass.
3658 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3659 GrowableArray<Method*>* prev_EMCP_methods) {
3660
3661 _prev_constant_pool = prev_constant_pool;
3662 _prev_EMCP_methods = prev_EMCP_methods;
3663 }
3664
3665
3666 // Destroy a PreviousVersionNode
3667 PreviousVersionNode::~PreviousVersionNode() {
3668 if (_prev_constant_pool != NULL) {
3669 _prev_constant_pool = NULL;
3670 }
3671
3672 if (_prev_EMCP_methods != NULL) {
3673 delete _prev_EMCP_methods;
3674 }
3675 }
3676
3677 // Construct a helper for walking the previous versions array
3678 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3679 _thread = thread;
3680 _previous_versions = ik->previous_versions();
3681 _current_index = 0;
3682 _current_p = NULL;
3683 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3684 }
3685
3686
3687 // Return the interesting information for the next previous version
3688 // of the klass. Returns NULL if there are no more previous versions.
3689 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3690 if (_previous_versions == NULL) {
3691 // no previous versions so nothing to return
3692 return NULL;
3693 }
3694
3695 _current_p = NULL; // reset to NULL
3696 _current_constant_pool_handle = NULL;
3697
3698 int length = _previous_versions->length();
3699
3700 while (_current_index < length) {
3701 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3702
3703 // Save a handle to the constant pool for this previous version,
3704 // which keeps all the methods from being deallocated.
3705 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3706 _current_p = pv_node;
3707 return pv_node;
3708 }
3709
3710 return NULL;
3711 } // end next_previous_version()