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/methodComparator.hpp"
52 #include "runtime/fieldDescriptor.hpp"
53 #include "runtime/handles.inline.hpp"
54 #include "runtime/javaCalls.hpp"
55 #include "runtime/mutexLocker.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "services/threadService.hpp"
58 #include "utilities/dtrace.hpp"
59 #include "utilities/macros.hpp"
60 #if INCLUDE_ALL_GCS
61 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
62 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
63 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
64 #include "gc_implementation/g1/g1RemSet.inline.hpp"
65 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
66 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
67 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
68 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
69 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
70 #include "oops/oop.pcgc.inline.hpp"
71 #endif // INCLUDE_ALL_GCS
72 #ifdef COMPILER1
73 #include "c1/c1_Compiler.hpp"
74 #endif
75
76 #ifdef DTRACE_ENABLED
77
78 #ifndef USDT2
79
80 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
81 char*, intptr_t, oop, intptr_t);
82 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
83 char*, intptr_t, oop, intptr_t, int);
84 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
85 char*, intptr_t, oop, intptr_t, int);
86 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
87 char*, intptr_t, oop, intptr_t, int);
88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
89 char*, intptr_t, oop, intptr_t, int);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
95 char*, intptr_t, oop, intptr_t, int);
96
97 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
98 { \
99 char* data = NULL; \
100 int len = 0; \
101 Symbol* name = (clss)->name(); \
102 if (name != NULL) { \
103 data = (char*)name->bytes(); \
104 len = name->utf8_length(); \
105 } \
106 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
107 data, len, (clss)->class_loader(), thread_type); \
108 }
109
110 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
111 { \
112 char* data = NULL; \
113 int len = 0; \
114 Symbol* name = (clss)->name(); \
115 if (name != NULL) { \
116 data = (char*)name->bytes(); \
117 len = name->utf8_length(); \
118 } \
119 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
120 data, len, (clss)->class_loader(), thread_type, wait); \
121 }
122 #else /* USDT2 */
123
124 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
125 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
126 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
127 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
128 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
129 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
130 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
131 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
132 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
133 { \
134 char* data = NULL; \
135 int len = 0; \
136 Symbol* name = (clss)->name(); \
137 if (name != NULL) { \
138 data = (char*)name->bytes(); \
139 len = name->utf8_length(); \
140 } \
141 HOTSPOT_CLASS_INITIALIZATION_##type( \
142 data, len, (clss)->class_loader(), thread_type); \
143 }
144
145 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
146 { \
147 char* data = NULL; \
148 int len = 0; \
149 Symbol* name = (clss)->name(); \
150 if (name != NULL) { \
151 data = (char*)name->bytes(); \
152 len = name->utf8_length(); \
153 } \
154 HOTSPOT_CLASS_INITIALIZATION_##type( \
155 data, len, (clss)->class_loader(), thread_type, wait); \
156 }
157 #endif /* USDT2 */
158
159 #else // ndef DTRACE_ENABLED
160
161 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
162 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
163
164 #endif // ndef DTRACE_ENABLED
165
166 volatile int InstanceKlass::_total_instanceKlass_count = 0;
167
168 InstanceKlass* InstanceKlass::allocate_instance_klass(
169 ClassLoaderData* loader_data,
170 int vtable_len,
171 int itable_len,
172 int static_field_size,
173 int nonstatic_oop_map_size,
174 ReferenceType rt,
175 AccessFlags access_flags,
176 Symbol* name,
177 Klass* super_klass,
178 bool is_anonymous,
179 TRAPS) {
180
181 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
182 access_flags.is_interface(), is_anonymous);
183
184 // Allocation
185 InstanceKlass* ik;
186 if (rt == REF_NONE) {
187 if (name == vmSymbols::java_lang_Class()) {
188 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
189 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
190 access_flags, is_anonymous);
191 } else if (name == vmSymbols::java_lang_ClassLoader() ||
192 (SystemDictionary::ClassLoader_klass_loaded() &&
193 super_klass != NULL &&
194 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
195 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
196 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
197 access_flags, is_anonymous);
198 } else {
199 // normal class
200 ik = new (loader_data, size, THREAD) InstanceKlass(
201 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
202 access_flags, is_anonymous);
203 }
204 } else {
205 // reference klass
206 ik = new (loader_data, size, THREAD) InstanceRefKlass(
207 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
208 access_flags, is_anonymous);
209 }
210
211 // Check for pending exception before adding to the loader data and incrementing
212 // class count. Can get OOM here.
213 if (HAS_PENDING_EXCEPTION) {
214 return NULL;
215 }
216
217 // Add all classes to our internal class loader list here,
218 // including classes in the bootstrap (NULL) class loader.
219 loader_data->add_class(ik);
220
221 Atomic::inc(&_total_instanceKlass_count);
222 return ik;
223 }
224
225
226 // copy method ordering from resource area to Metaspace
227 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
228 if (m != NULL) {
229 // allocate a new array and copy contents (memcpy?)
230 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
231 for (int i = 0; i < m->length(); i++) {
232 _method_ordering->at_put(i, m->at(i));
233 }
234 } else {
235 _method_ordering = Universe::the_empty_int_array();
236 }
237 }
238
239
240 InstanceKlass::InstanceKlass(int vtable_len,
241 int itable_len,
242 int static_field_size,
243 int nonstatic_oop_map_size,
244 ReferenceType rt,
245 AccessFlags access_flags,
246 bool is_anonymous) {
247 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
248
249 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
250 access_flags.is_interface(), is_anonymous);
251
252 set_vtable_length(vtable_len);
253 set_itable_length(itable_len);
254 set_static_field_size(static_field_size);
255 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
256 set_access_flags(access_flags);
257 _misc_flags = 0; // initialize to zero
258 set_is_anonymous(is_anonymous);
259 assert(size() == iksize, "wrong size for object");
260
261 set_array_klasses(NULL);
262 set_methods(NULL);
263 set_method_ordering(NULL);
264 set_local_interfaces(NULL);
265 set_transitive_interfaces(NULL);
266 init_implementor();
267 set_fields(NULL, 0);
268 set_constants(NULL);
269 set_class_loader_data(NULL);
270 set_protection_domain(NULL);
271 set_signers(NULL);
272 set_source_file_name(NULL);
273 set_source_debug_extension(NULL, 0);
274 set_array_name(NULL);
275 set_inner_classes(NULL);
276 set_static_oop_field_count(0);
277 set_nonstatic_field_size(0);
278 set_is_marked_dependent(false);
279 set_init_state(InstanceKlass::allocated);
280 set_init_thread(NULL);
281 set_init_lock(NULL);
282 set_reference_type(rt);
283 set_oop_map_cache(NULL);
284 set_jni_ids(NULL);
285 set_osr_nmethods_head(NULL);
286 set_breakpoints(NULL);
287 init_previous_versions();
288 set_generic_signature(NULL);
289 release_set_methods_jmethod_ids(NULL);
290 release_set_methods_cached_itable_indices(NULL);
291 set_annotations(NULL);
292 set_jvmti_cached_class_field_map(NULL);
293 set_initial_method_idnum(0);
294 _dependencies = NULL;
295 set_jvmti_cached_class_field_map(NULL);
296 set_cached_class_file(NULL, 0);
297 set_initial_method_idnum(0);
298 set_minor_version(0);
299 set_major_version(0);
300 NOT_PRODUCT(_verify_count = 0;)
301
302 // initialize the non-header words to zero
303 intptr_t* p = (intptr_t*)this;
304 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
305 p[index] = NULL_WORD;
306 }
307
308 // Set temporary value until parseClassFile updates it with the real instance
309 // size.
310 set_layout_helper(Klass::instance_layout_helper(0, true));
311 }
312
313
314 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
315 Array<Method*>* methods) {
316 if (methods != NULL && methods != Universe::the_empty_method_array()) {
317 for (int i = 0; i < methods->length(); i++) {
318 Method* method = methods->at(i);
319 if (method == NULL) continue; // maybe null if error processing
320 // Only want to delete methods that are not executing for RedefineClasses.
321 // The previous version will point to them so they're not totally dangling
322 assert (!method->on_stack(), "shouldn't be called with methods on stack");
323 MetadataFactory::free_metadata(loader_data, method);
324 }
325 MetadataFactory::free_array<Method*>(loader_data, methods);
326 }
327 }
328
329 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
330 Klass* super_klass,
331 Array<Klass*>* local_interfaces,
332 Array<Klass*>* transitive_interfaces) {
333 // Only deallocate transitive interfaces if not empty, same as super class
334 // or same as local interfaces. See code in parseClassFile.
335 Array<Klass*>* ti = transitive_interfaces;
336 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
337 // check that the interfaces don't come from super class
338 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
339 InstanceKlass::cast(super_klass)->transitive_interfaces();
340 if (ti != sti) {
341 MetadataFactory::free_array<Klass*>(loader_data, ti);
342 }
343 }
344
345 // local interfaces can be empty
346 if (local_interfaces != Universe::the_empty_klass_array()) {
347 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
348 }
349 }
350
351 // This function deallocates the metadata and C heap pointers that the
352 // InstanceKlass points to.
353 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
354
355 // Orphan the mirror first, CMS thinks it's still live.
356 if (java_mirror() != NULL) {
357 java_lang_Class::set_klass(java_mirror(), NULL);
358 }
359
360 // Need to take this class off the class loader data list.
361 loader_data->remove_class(this);
362
363 // The array_klass for this class is created later, after error handling.
364 // For class redefinition, we keep the original class so this scratch class
365 // doesn't have an array class. Either way, assert that there is nothing
366 // to deallocate.
367 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
368
369 // Release C heap allocated data that this might point to, which includes
370 // reference counting symbol names.
371 release_C_heap_structures();
372
373 deallocate_methods(loader_data, methods());
374 set_methods(NULL);
375
376 if (method_ordering() != Universe::the_empty_int_array()) {
377 MetadataFactory::free_array<int>(loader_data, method_ordering());
378 }
379 set_method_ordering(NULL);
380
381 // This array is in Klass, but remove it with the InstanceKlass since
382 // this place would be the only caller and it can share memory with transitive
383 // interfaces.
384 if (secondary_supers() != Universe::the_empty_klass_array() &&
385 secondary_supers() != transitive_interfaces()) {
386 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
387 }
388 set_secondary_supers(NULL);
389
390 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
391 set_transitive_interfaces(NULL);
392 set_local_interfaces(NULL);
393
394 MetadataFactory::free_array<jushort>(loader_data, fields());
395 set_fields(NULL, 0);
396
397 // If a method from a redefined class is using this constant pool, don't
398 // delete it, yet. The new class's previous version will point to this.
399 if (constants() != NULL) {
400 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
401 MetadataFactory::free_metadata(loader_data, constants());
402 set_constants(NULL);
403 }
404
405 if (inner_classes() != Universe::the_empty_short_array()) {
406 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
407 }
408 set_inner_classes(NULL);
409
410 // Null out Java heap objects, although these won't be walked to keep
411 // alive once this InstanceKlass is deallocated.
412 set_protection_domain(NULL);
413 set_signers(NULL);
414 set_init_lock(NULL);
415
416 // We should deallocate the Annotations instance
417 MetadataFactory::free_metadata(loader_data, annotations());
418 set_annotations(NULL);
419 }
420
421 volatile oop InstanceKlass::init_lock() const {
422 volatile oop lock = _init_lock; // read once
423 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
424 "only fully initialized state can have a null lock");
425 return lock;
426 }
427
428 // Set the initialization lock to null so the object can be GC'ed. Any racing
429 // threads to get this lock will see a null lock and will not lock.
430 // That's okay because they all check for initialized state after getting
431 // the lock and return.
432 void InstanceKlass::fence_and_clear_init_lock() {
433 // make sure previous stores are all done, notably the init_state.
434 OrderAccess::storestore();
435 klass_oop_store(&_init_lock, NULL);
436 assert(!is_not_initialized(), "class must be initialized now");
437 }
438
439
440 bool InstanceKlass::should_be_initialized() const {
441 return !is_initialized();
442 }
443
444 klassVtable* InstanceKlass::vtable() const {
445 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
446 }
447
448 klassItable* InstanceKlass::itable() const {
449 return new klassItable(instanceKlassHandle(this));
450 }
451
452 void InstanceKlass::eager_initialize(Thread *thread) {
453 if (!EagerInitialization) return;
454
455 if (this->is_not_initialized()) {
456 // abort if the the class has a class initializer
457 if (this->class_initializer() != NULL) return;
458
459 // abort if it is java.lang.Object (initialization is handled in genesis)
460 Klass* super = this->super();
461 if (super == NULL) return;
462
463 // abort if the super class should be initialized
464 if (!InstanceKlass::cast(super)->is_initialized()) return;
465
466 // call body to expose the this pointer
467 instanceKlassHandle this_oop(thread, this);
468 eager_initialize_impl(this_oop);
469 }
470 }
471
472
473 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
474 EXCEPTION_MARK;
475 volatile oop init_lock = this_oop->init_lock();
476 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
477
478 // abort if someone beat us to the initialization
479 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
480
481 ClassState old_state = this_oop->init_state();
482 link_class_impl(this_oop, true, THREAD);
483 if (HAS_PENDING_EXCEPTION) {
484 CLEAR_PENDING_EXCEPTION;
485 // Abort if linking the class throws an exception.
486
487 // Use a test to avoid redundantly resetting the state if there's
488 // no change. Set_init_state() asserts that state changes make
489 // progress, whereas here we might just be spinning in place.
490 if( old_state != this_oop->_init_state )
491 this_oop->set_init_state (old_state);
492 } else {
493 // linking successfull, mark class as initialized
494 this_oop->set_init_state (fully_initialized);
495 this_oop->fence_and_clear_init_lock();
496 // trace
497 if (TraceClassInitialization) {
498 ResourceMark rm(THREAD);
499 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
500 }
501 }
502 }
503
504
505 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
506 // process. The step comments refers to the procedure described in that section.
507 // Note: implementation moved to static method to expose the this pointer.
508 void InstanceKlass::initialize(TRAPS) {
509 if (this->should_be_initialized()) {
510 HandleMark hm(THREAD);
511 instanceKlassHandle this_oop(THREAD, this);
512 initialize_impl(this_oop, CHECK);
513 // Note: at this point the class may be initialized
514 // OR it may be in the state of being initialized
515 // in case of recursive initialization!
516 } else {
517 assert(is_initialized(), "sanity check");
518 }
519 }
520
521
522 bool InstanceKlass::verify_code(
523 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
524 // 1) Verify the bytecodes
525 Verifier::Mode mode =
526 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
527 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
528 }
529
530
531 // Used exclusively by the shared spaces dump mechanism to prevent
532 // classes mapped into the shared regions in new VMs from appearing linked.
533
534 void InstanceKlass::unlink_class() {
535 assert(is_linked(), "must be linked");
536 _init_state = loaded;
537 }
538
539 void InstanceKlass::link_class(TRAPS) {
540 assert(is_loaded(), "must be loaded");
541 if (!is_linked()) {
542 HandleMark hm(THREAD);
543 instanceKlassHandle this_oop(THREAD, this);
544 link_class_impl(this_oop, true, CHECK);
545 }
546 }
547
548 // Called to verify that a class can link during initialization, without
549 // throwing a VerifyError.
550 bool InstanceKlass::link_class_or_fail(TRAPS) {
551 assert(is_loaded(), "must be loaded");
552 if (!is_linked()) {
553 HandleMark hm(THREAD);
554 instanceKlassHandle this_oop(THREAD, this);
555 link_class_impl(this_oop, false, CHECK_false);
556 }
557 return is_linked();
558 }
559
560 bool InstanceKlass::link_class_impl(
561 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
562 // check for error state
563 if (this_oop->is_in_error_state()) {
564 ResourceMark rm(THREAD);
565 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
566 this_oop->external_name(), false);
567 }
568 // return if already verified
569 if (this_oop->is_linked()) {
570 return true;
571 }
572
573 // Timing
574 // timer handles recursion
575 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
576 JavaThread* jt = (JavaThread*)THREAD;
577
578 // link super class before linking this class
579 instanceKlassHandle super(THREAD, this_oop->super());
580 if (super.not_null()) {
581 if (super->is_interface()) { // check if super class is an interface
582 ResourceMark rm(THREAD);
583 Exceptions::fthrow(
584 THREAD_AND_LOCATION,
585 vmSymbols::java_lang_IncompatibleClassChangeError(),
586 "class %s has interface %s as super class",
587 this_oop->external_name(),
588 super->external_name()
589 );
590 return false;
591 }
592
593 link_class_impl(super, throw_verifyerror, CHECK_false);
594 }
595
596 // link all interfaces implemented by this class before linking this class
597 Array<Klass*>* interfaces = this_oop->local_interfaces();
598 int num_interfaces = interfaces->length();
599 for (int index = 0; index < num_interfaces; index++) {
600 HandleMark hm(THREAD);
601 instanceKlassHandle ih(THREAD, interfaces->at(index));
602 link_class_impl(ih, throw_verifyerror, CHECK_false);
603 }
604
605 // in case the class is linked in the process of linking its superclasses
606 if (this_oop->is_linked()) {
607 return true;
608 }
609
610 // trace only the link time for this klass that includes
611 // the verification time
612 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
613 ClassLoader::perf_class_link_selftime(),
614 ClassLoader::perf_classes_linked(),
615 jt->get_thread_stat()->perf_recursion_counts_addr(),
616 jt->get_thread_stat()->perf_timers_addr(),
617 PerfClassTraceTime::CLASS_LINK);
618
619 // verification & rewriting
620 {
621 volatile oop init_lock = this_oop->init_lock();
622 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
623 // rewritten will have been set if loader constraint error found
624 // on an earlier link attempt
625 // don't verify or rewrite if already rewritten
626
627 if (!this_oop->is_linked()) {
628 if (!this_oop->is_rewritten()) {
629 {
630 // Timer includes any side effects of class verification (resolution,
631 // etc), but not recursive entry into verify_code().
632 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
633 ClassLoader::perf_class_verify_selftime(),
634 ClassLoader::perf_classes_verified(),
635 jt->get_thread_stat()->perf_recursion_counts_addr(),
636 jt->get_thread_stat()->perf_timers_addr(),
637 PerfClassTraceTime::CLASS_VERIFY);
638 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
639 if (!verify_ok) {
640 return false;
641 }
642 }
643
644 // Just in case a side-effect of verify linked this class already
645 // (which can sometimes happen since the verifier loads classes
646 // using custom class loaders, which are free to initialize things)
647 if (this_oop->is_linked()) {
648 return true;
649 }
650
651 // also sets rewritten
652 this_oop->rewrite_class(CHECK_false);
653 }
654
655 // relocate jsrs and link methods after they are all rewritten
656 this_oop->link_methods(CHECK_false);
657
658 // Initialize the vtable and interface table after
659 // methods have been rewritten since rewrite may
660 // fabricate new Method*s.
661 // also does loader constraint checking
662 if (!this_oop()->is_shared()) {
663 ResourceMark rm(THREAD);
664 this_oop->vtable()->initialize_vtable(true, CHECK_false);
665 this_oop->itable()->initialize_itable(true, CHECK_false);
666 }
667 #ifdef ASSERT
668 else {
669 ResourceMark rm(THREAD);
670 this_oop->vtable()->verify(tty, true);
671 // In case itable verification is ever added.
672 // this_oop->itable()->verify(tty, true);
673 }
674 #endif
675 this_oop->set_init_state(linked);
676 if (JvmtiExport::should_post_class_prepare()) {
677 Thread *thread = THREAD;
678 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
679 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
680 }
681 }
682 }
683 return true;
684 }
685
686
687 // Rewrite the byte codes of all of the methods of a class.
688 // The rewriter must be called exactly once. Rewriting must happen after
689 // verification but before the first method of the class is executed.
690 void InstanceKlass::rewrite_class(TRAPS) {
691 assert(is_loaded(), "must be loaded");
692 instanceKlassHandle this_oop(THREAD, this);
693 if (this_oop->is_rewritten()) {
694 assert(this_oop()->is_shared(), "rewriting an unshared class?");
695 return;
696 }
697 Rewriter::rewrite(this_oop, CHECK);
698 this_oop->set_rewritten();
699 }
700
701 // Now relocate and link method entry points after class is rewritten.
702 // This is outside is_rewritten flag. In case of an exception, it can be
703 // executed more than once.
704 void InstanceKlass::link_methods(TRAPS) {
705 int len = methods()->length();
706 for (int i = len-1; i >= 0; i--) {
707 methodHandle m(THREAD, methods()->at(i));
708
709 // Set up method entry points for compiler and interpreter .
710 m->link_method(m, CHECK);
711
712 // This is for JVMTI and unrelated to relocator but the last thing we do
713 #ifdef ASSERT
714 if (StressMethodComparator) {
715 ResourceMark rm(THREAD);
716 static int nmc = 0;
717 for (int j = i; j >= 0 && j >= i-4; j--) {
718 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
719 bool z = MethodComparator::methods_EMCP(m(),
720 methods()->at(j));
721 if (j == i && !z) {
722 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
723 assert(z, "method must compare equal to itself");
724 }
725 }
726 }
727 #endif //ASSERT
728 }
729 }
730
731
732 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
733 // Make sure klass is linked (verified) before initialization
734 // A class could already be verified, since it has been reflected upon.
735 this_oop->link_class(CHECK);
736
737 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
738
739 bool wait = false;
740
741 // refer to the JVM book page 47 for description of steps
742 // Step 1
743 {
744 volatile oop init_lock = this_oop->init_lock();
745 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
746
747 Thread *self = THREAD; // it's passed the current thread
748
749 // Step 2
750 // If we were to use wait() instead of waitInterruptibly() then
751 // we might end up throwing IE from link/symbol resolution sites
752 // that aren't expected to throw. This would wreak havoc. See 6320309.
753 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
754 wait = true;
755 ol.waitUninterruptibly(CHECK);
756 }
757
758 // Step 3
759 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
760 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
761 return;
762 }
763
764 // Step 4
765 if (this_oop->is_initialized()) {
766 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
767 return;
768 }
769
770 // Step 5
771 if (this_oop->is_in_error_state()) {
772 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
773 ResourceMark rm(THREAD);
774 const char* desc = "Could not initialize class ";
775 const char* className = this_oop->external_name();
776 size_t msglen = strlen(desc) + strlen(className) + 1;
777 char* message = NEW_RESOURCE_ARRAY(char, msglen);
778 if (NULL == message) {
779 // Out of memory: can't create detailed error message
780 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
781 } else {
782 jio_snprintf(message, msglen, "%s%s", desc, className);
783 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
784 }
785 }
786
787 // Step 6
788 this_oop->set_init_state(being_initialized);
789 this_oop->set_init_thread(self);
790 }
791
792 // Step 7
793 Klass* super_klass = this_oop->super();
794 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
795 super_klass->initialize(THREAD);
796
797 if (HAS_PENDING_EXCEPTION) {
798 Handle e(THREAD, PENDING_EXCEPTION);
799 CLEAR_PENDING_EXCEPTION;
800 {
801 EXCEPTION_MARK;
802 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
803 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
804 }
805 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
806 THROW_OOP(e());
807 }
808 }
809
810 if (this_oop->has_default_methods()) {
811 // Step 7.5: initialize any interfaces which have default methods
812 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
813 Klass* iface = this_oop->local_interfaces()->at(i);
814 InstanceKlass* ik = InstanceKlass::cast(iface);
815 if (ik->has_default_methods() && ik->should_be_initialized()) {
816 ik->initialize(THREAD);
817
818 if (HAS_PENDING_EXCEPTION) {
819 Handle e(THREAD, PENDING_EXCEPTION);
820 CLEAR_PENDING_EXCEPTION;
821 {
822 EXCEPTION_MARK;
823 // Locks object, set state, and notify all waiting threads
824 this_oop->set_initialization_state_and_notify(
825 initialization_error, THREAD);
826
827 // ignore any exception thrown, superclass initialization error is
828 // thrown below
829 CLEAR_PENDING_EXCEPTION;
830 }
831 DTRACE_CLASSINIT_PROBE_WAIT(
832 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
833 THROW_OOP(e());
834 }
835 }
836 }
837 }
838
839 // Step 8
840 {
841 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
842 JavaThread* jt = (JavaThread*)THREAD;
843 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
844 // Timer includes any side effects of class initialization (resolution,
845 // etc), but not recursive entry into call_class_initializer().
846 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
847 ClassLoader::perf_class_init_selftime(),
848 ClassLoader::perf_classes_inited(),
849 jt->get_thread_stat()->perf_recursion_counts_addr(),
850 jt->get_thread_stat()->perf_timers_addr(),
851 PerfClassTraceTime::CLASS_CLINIT);
852 this_oop->call_class_initializer(THREAD);
853 }
854
855 // Step 9
856 if (!HAS_PENDING_EXCEPTION) {
857 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
858 { ResourceMark rm(THREAD);
859 debug_only(this_oop->vtable()->verify(tty, true);)
860 }
861 }
862 else {
863 // Step 10 and 11
864 Handle e(THREAD, PENDING_EXCEPTION);
865 CLEAR_PENDING_EXCEPTION;
866 {
867 EXCEPTION_MARK;
868 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
869 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
870 }
871 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
872 if (e->is_a(SystemDictionary::Error_klass())) {
873 THROW_OOP(e());
874 } else {
875 JavaCallArguments args(e);
876 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
877 vmSymbols::throwable_void_signature(),
878 &args);
879 }
880 }
881 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
882 }
883
884
885 // Note: implementation moved to static method to expose the this pointer.
886 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
887 instanceKlassHandle kh(THREAD, this);
888 set_initialization_state_and_notify_impl(kh, state, CHECK);
889 }
890
891 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
892 volatile oop init_lock = this_oop->init_lock();
893 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
894 this_oop->set_init_state(state);
895 this_oop->fence_and_clear_init_lock();
896 ol.notify_all(CHECK);
897 }
898
899 // The embedded _implementor field can only record one implementor.
900 // When there are more than one implementors, the _implementor field
901 // is set to the interface Klass* itself. Following are the possible
902 // values for the _implementor field:
903 // NULL - no implementor
904 // implementor Klass* - one implementor
905 // self - more than one implementor
906 //
907 // The _implementor field only exists for interfaces.
908 void InstanceKlass::add_implementor(Klass* k) {
909 assert(Compile_lock->owned_by_self(), "");
910 assert(is_interface(), "not interface");
911 // Filter out my subinterfaces.
912 // (Note: Interfaces are never on the subklass list.)
913 if (InstanceKlass::cast(k)->is_interface()) return;
914
915 // Filter out subclasses whose supers already implement me.
916 // (Note: CHA must walk subclasses of direct implementors
917 // in order to locate indirect implementors.)
918 Klass* sk = InstanceKlass::cast(k)->super();
919 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
920 // We only need to check one immediate superclass, since the
921 // implements_interface query looks at transitive_interfaces.
922 // Any supers of the super have the same (or fewer) transitive_interfaces.
923 return;
924
925 Klass* ik = implementor();
926 if (ik == NULL) {
927 set_implementor(k);
928 } else if (ik != this) {
929 // There is already an implementor. Use itself as an indicator of
930 // more than one implementors.
931 set_implementor(this);
932 }
933
934 // The implementor also implements the transitive_interfaces
935 for (int index = 0; index < local_interfaces()->length(); index++) {
936 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
937 }
938 }
939
940 void InstanceKlass::init_implementor() {
941 if (is_interface()) {
942 set_implementor(NULL);
943 }
944 }
945
946
947 void InstanceKlass::process_interfaces(Thread *thread) {
948 // link this class into the implementors list of every interface it implements
949 Klass* this_as_klass_oop = this;
950 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
951 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
952 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
953 assert(interf->is_interface(), "expected interface");
954 interf->add_implementor(this_as_klass_oop);
955 }
956 }
957
958 bool InstanceKlass::can_be_primary_super_slow() const {
959 if (is_interface())
960 return false;
961 else
962 return Klass::can_be_primary_super_slow();
963 }
964
965 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
966 // The secondaries are the implemented interfaces.
967 InstanceKlass* ik = InstanceKlass::cast(this);
968 Array<Klass*>* interfaces = ik->transitive_interfaces();
969 int num_secondaries = num_extra_slots + interfaces->length();
970 if (num_secondaries == 0) {
971 // Must share this for correct bootstrapping!
972 set_secondary_supers(Universe::the_empty_klass_array());
973 return NULL;
974 } else if (num_extra_slots == 0) {
975 // The secondary super list is exactly the same as the transitive interfaces.
976 // Redefine classes has to be careful not to delete this!
977 set_secondary_supers(interfaces);
978 return NULL;
979 } else {
980 // Copy transitive interfaces to a temporary growable array to be constructed
981 // into the secondary super list with extra slots.
982 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
983 for (int i = 0; i < interfaces->length(); i++) {
984 secondaries->push(interfaces->at(i));
985 }
986 return secondaries;
987 }
988 }
989
990 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
991 if (k->is_interface()) {
992 return implements_interface(k);
993 } else {
994 return Klass::compute_is_subtype_of(k);
995 }
996 }
997
998 bool InstanceKlass::implements_interface(Klass* k) const {
999 if (this == k) return true;
1000 assert(k->is_interface(), "should be an interface class");
1001 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1002 if (transitive_interfaces()->at(i) == k) {
1003 return true;
1004 }
1005 }
1006 return false;
1007 }
1008
1009 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1010 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1011 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1012 report_java_out_of_memory("Requested array size exceeds VM limit");
1013 JvmtiExport::post_array_size_exhausted();
1014 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1015 }
1016 int size = objArrayOopDesc::object_size(length);
1017 Klass* ak = array_klass(n, CHECK_NULL);
1018 KlassHandle h_ak (THREAD, ak);
1019 objArrayOop o =
1020 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1021 return o;
1022 }
1023
1024 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1025 if (TraceFinalizerRegistration) {
1026 tty->print("Registered ");
1027 i->print_value_on(tty);
1028 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1029 }
1030 instanceHandle h_i(THREAD, i);
1031 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1032 JavaValue result(T_VOID);
1033 JavaCallArguments args(h_i);
1034 methodHandle mh (THREAD, Universe::finalizer_register_method());
1035 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1036 return h_i();
1037 }
1038
1039 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1040 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1041 int size = size_helper(); // Query before forming handle.
1042
1043 KlassHandle h_k(THREAD, this);
1044
1045 instanceOop i;
1046
1047 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1048 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1049 i = register_finalizer(i, CHECK_NULL);
1050 }
1051 return i;
1052 }
1053
1054 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1055 if (is_interface() || is_abstract()) {
1056 ResourceMark rm(THREAD);
1057 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1058 : vmSymbols::java_lang_InstantiationException(), external_name());
1059 }
1060 if (this == SystemDictionary::Class_klass()) {
1061 ResourceMark rm(THREAD);
1062 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1063 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1064 }
1065 }
1066
1067 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1068 instanceKlassHandle this_oop(THREAD, this);
1069 return array_klass_impl(this_oop, or_null, n, THREAD);
1070 }
1071
1072 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1073 if (this_oop->array_klasses() == NULL) {
1074 if (or_null) return NULL;
1075
1076 ResourceMark rm;
1077 JavaThread *jt = (JavaThread *)THREAD;
1078 {
1079 // Atomic creation of array_klasses
1080 MutexLocker mc(Compile_lock, THREAD); // for vtables
1081 MutexLocker ma(MultiArray_lock, THREAD);
1082
1083 // Check if update has already taken place
1084 if (this_oop->array_klasses() == NULL) {
1085 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1086 this_oop->set_array_klasses(k);
1087 }
1088 }
1089 }
1090 // _this will always be set at this point
1091 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1092 if (or_null) {
1093 return oak->array_klass_or_null(n);
1094 }
1095 return oak->array_klass(n, CHECK_NULL);
1096 }
1097
1098 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1099 return array_klass_impl(or_null, 1, THREAD);
1100 }
1101
1102 void InstanceKlass::call_class_initializer(TRAPS) {
1103 instanceKlassHandle ik (THREAD, this);
1104 call_class_initializer_impl(ik, THREAD);
1105 }
1106
1107 static int call_class_initializer_impl_counter = 0; // for debugging
1108
1109 Method* InstanceKlass::class_initializer() {
1110 Method* clinit = find_method(
1111 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1112 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1113 return clinit;
1114 }
1115 return NULL;
1116 }
1117
1118 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1119 if (ReplayCompiles &&
1120 (ReplaySuppressInitializers == 1 ||
1121 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1122 // Hide the existence of the initializer for the purpose of replaying the compile
1123 return;
1124 }
1125
1126 methodHandle h_method(THREAD, this_oop->class_initializer());
1127 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1128 if (TraceClassInitialization) {
1129 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1130 this_oop->name()->print_value();
1131 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1132 }
1133 if (h_method() != NULL) {
1134 JavaCallArguments args; // No arguments
1135 JavaValue result(T_VOID);
1136 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1137 }
1138 }
1139
1140
1141 void InstanceKlass::mask_for(methodHandle method, int bci,
1142 InterpreterOopMap* entry_for) {
1143 // Dirty read, then double-check under a lock.
1144 if (_oop_map_cache == NULL) {
1145 // Otherwise, allocate a new one.
1146 MutexLocker x(OopMapCacheAlloc_lock);
1147 // First time use. Allocate a cache in C heap
1148 if (_oop_map_cache == NULL) {
1149 _oop_map_cache = new OopMapCache();
1150 }
1151 }
1152 // _oop_map_cache is constant after init; lookup below does is own locking.
1153 _oop_map_cache->lookup(method, bci, entry_for);
1154 }
1155
1156
1157 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1158 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1159 Symbol* f_name = fs.name();
1160 Symbol* f_sig = fs.signature();
1161 if (f_name == name && f_sig == sig) {
1162 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1163 return true;
1164 }
1165 }
1166 return false;
1167 }
1168
1169
1170 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1171 const int n = local_interfaces()->length();
1172 for (int i = 0; i < n; i++) {
1173 Klass* intf1 = local_interfaces()->at(i);
1174 assert(intf1->is_interface(), "just checking type");
1175 // search for field in current interface
1176 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1177 assert(fd->is_static(), "interface field must be static");
1178 return intf1;
1179 }
1180 // search for field in direct superinterfaces
1181 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1182 if (intf2 != NULL) return intf2;
1183 }
1184 // otherwise field lookup fails
1185 return NULL;
1186 }
1187
1188
1189 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1190 // search order according to newest JVM spec (5.4.3.2, p.167).
1191 // 1) search for field in current klass
1192 if (find_local_field(name, sig, fd)) {
1193 return const_cast<InstanceKlass*>(this);
1194 }
1195 // 2) search for field recursively in direct superinterfaces
1196 { Klass* intf = find_interface_field(name, sig, fd);
1197 if (intf != NULL) return intf;
1198 }
1199 // 3) apply field lookup recursively if superclass exists
1200 { Klass* supr = super();
1201 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1202 }
1203 // 4) otherwise field lookup fails
1204 return NULL;
1205 }
1206
1207
1208 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1209 // search order according to newest JVM spec (5.4.3.2, p.167).
1210 // 1) search for field in current klass
1211 if (find_local_field(name, sig, fd)) {
1212 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1213 }
1214 // 2) search for field recursively in direct superinterfaces
1215 if (is_static) {
1216 Klass* intf = find_interface_field(name, sig, fd);
1217 if (intf != NULL) return intf;
1218 }
1219 // 3) apply field lookup recursively if superclass exists
1220 { Klass* supr = super();
1221 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1222 }
1223 // 4) otherwise field lookup fails
1224 return NULL;
1225 }
1226
1227
1228 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1229 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1230 if (fs.offset() == offset) {
1231 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1232 if (fd->is_static() == is_static) return true;
1233 }
1234 }
1235 return false;
1236 }
1237
1238
1239 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1240 Klass* klass = const_cast<InstanceKlass*>(this);
1241 while (klass != NULL) {
1242 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1243 return true;
1244 }
1245 klass = klass->super();
1246 }
1247 return false;
1248 }
1249
1250
1251 void InstanceKlass::methods_do(void f(Method* method)) {
1252 int len = methods()->length();
1253 for (int index = 0; index < len; index++) {
1254 Method* m = methods()->at(index);
1255 assert(m->is_method(), "must be method");
1256 f(m);
1257 }
1258 }
1259
1260
1261 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1262 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1263 if (fs.access_flags().is_static()) {
1264 fieldDescriptor fd;
1265 fd.initialize(this, fs.index());
1266 cl->do_field(&fd);
1267 }
1268 }
1269 }
1270
1271
1272 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
1273 instanceKlassHandle h_this(THREAD, this);
1274 do_local_static_fields_impl(h_this, f, CHECK);
1275 }
1276
1277
1278 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
1279 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
1280 if (fs.access_flags().is_static()) {
1281 fieldDescriptor fd;
1282 fd.initialize(this_oop(), fs.index());
1283 f(&fd, CHECK);
1284 }
1285 }
1286 }
1287
1288
1289 static int compare_fields_by_offset(int* a, int* b) {
1290 return a[0] - b[0];
1291 }
1292
1293 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1294 InstanceKlass* super = superklass();
1295 if (super != NULL) {
1296 super->do_nonstatic_fields(cl);
1297 }
1298 fieldDescriptor fd;
1299 int length = java_fields_count();
1300 // In DebugInfo nonstatic fields are sorted by offset.
1301 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1302 int j = 0;
1303 for (int i = 0; i < length; i += 1) {
1304 fd.initialize(this, i);
1305 if (!fd.is_static()) {
1306 fields_sorted[j + 0] = fd.offset();
1307 fields_sorted[j + 1] = i;
1308 j += 2;
1309 }
1310 }
1311 if (j > 0) {
1312 length = j;
1313 // _sort_Fn is defined in growableArray.hpp.
1314 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1315 for (int i = 0; i < length; i += 2) {
1316 fd.initialize(this, fields_sorted[i + 1]);
1317 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1318 cl->do_field(&fd);
1319 }
1320 }
1321 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1322 }
1323
1324
1325 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1326 if (array_klasses() != NULL)
1327 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1328 }
1329
1330 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1331 if (array_klasses() != NULL)
1332 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1333 }
1334
1335
1336 void InstanceKlass::with_array_klasses_do(void f(Klass* k)) {
1337 f(this);
1338 array_klasses_do(f);
1339 }
1340
1341 #ifdef ASSERT
1342 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1343 int len = methods->length();
1344 for (int index = 0; index < len; index++) {
1345 Method* m = methods->at(index);
1346 assert(m->is_method(), "must be method");
1347 if (m->signature() == signature && m->name() == name) {
1348 return index;
1349 }
1350 }
1351 return -1;
1352 }
1353 #endif
1354
1355 static int binary_search(Array<Method*>* methods, Symbol* name) {
1356 int len = methods->length();
1357 // methods are sorted, so do binary search
1358 int l = 0;
1359 int h = len - 1;
1360 while (l <= h) {
1361 int mid = (l + h) >> 1;
1362 Method* m = methods->at(mid);
1363 assert(m->is_method(), "must be method");
1364 int res = m->name()->fast_compare(name);
1365 if (res == 0) {
1366 return mid;
1367 } else if (res < 0) {
1368 l = mid + 1;
1369 } else {
1370 h = mid - 1;
1371 }
1372 }
1373 return -1;
1374 }
1375
1376 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1377 return InstanceKlass::find_method(methods(), name, signature);
1378 }
1379
1380 Method* InstanceKlass::find_method(
1381 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1382 int hit = binary_search(methods, name);
1383 if (hit != -1) {
1384 Method* m = methods->at(hit);
1385 // Do linear search to find matching signature. First, quick check
1386 // for common case
1387 if (m->signature() == signature) return m;
1388 // search downwards through overloaded methods
1389 int i;
1390 for (i = hit - 1; i >= 0; --i) {
1391 Method* m = methods->at(i);
1392 assert(m->is_method(), "must be method");
1393 if (m->name() != name) break;
1394 if (m->signature() == signature) return m;
1395 }
1396 // search upwards
1397 for (i = hit + 1; i < methods->length(); ++i) {
1398 Method* m = methods->at(i);
1399 assert(m->is_method(), "must be method");
1400 if (m->name() != name) break;
1401 if (m->signature() == signature) return m;
1402 }
1403 // not found
1404 #ifdef ASSERT
1405 int index = linear_search(methods, name, signature);
1406 assert(index == -1, err_msg("binary search should have found entry %d", index));
1407 #endif
1408 }
1409 return NULL;
1410 }
1411
1412 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1413 return find_method_by_name(methods(), name, end);
1414 }
1415
1416 int InstanceKlass::find_method_by_name(
1417 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1418 assert(end_ptr != NULL, "just checking");
1419 int start = binary_search(methods, name);
1420 int end = start + 1;
1421 if (start != -1) {
1422 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1423 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1424 *end_ptr = end;
1425 return start;
1426 }
1427 return -1;
1428 }
1429
1430 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1431 Klass* klass = const_cast<InstanceKlass*>(this);
1432 while (klass != NULL) {
1433 Method* method = InstanceKlass::cast(klass)->find_method(name, signature);
1434 if (method != NULL) return method;
1435 klass = InstanceKlass::cast(klass)->super();
1436 }
1437 return NULL;
1438 }
1439
1440 // lookup a method in all the interfaces that this class implements
1441 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1442 Symbol* signature) const {
1443 Array<Klass*>* all_ifs = transitive_interfaces();
1444 int num_ifs = all_ifs->length();
1445 InstanceKlass *ik = NULL;
1446 for (int i = 0; i < num_ifs; i++) {
1447 ik = InstanceKlass::cast(all_ifs->at(i));
1448 Method* m = ik->lookup_method(name, signature);
1449 if (m != NULL) {
1450 return m;
1451 }
1452 }
1453 return NULL;
1454 }
1455
1456 /* jni_id_for_impl for jfieldIds only */
1457 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1458 MutexLocker ml(JfieldIdCreation_lock);
1459 // Retry lookup after we got the lock
1460 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1461 if (probe == NULL) {
1462 // Slow case, allocate new static field identifier
1463 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1464 this_oop->set_jni_ids(probe);
1465 }
1466 return probe;
1467 }
1468
1469
1470 /* jni_id_for for jfieldIds only */
1471 JNIid* InstanceKlass::jni_id_for(int offset) {
1472 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1473 if (probe == NULL) {
1474 probe = jni_id_for_impl(this, offset);
1475 }
1476 return probe;
1477 }
1478
1479 u2 InstanceKlass::enclosing_method_data(int offset) {
1480 Array<jushort>* inner_class_list = inner_classes();
1481 if (inner_class_list == NULL) {
1482 return 0;
1483 }
1484 int length = inner_class_list->length();
1485 if (length % inner_class_next_offset == 0) {
1486 return 0;
1487 } else {
1488 int index = length - enclosing_method_attribute_size;
1489 assert(offset < enclosing_method_attribute_size, "invalid offset");
1490 return inner_class_list->at(index + offset);
1491 }
1492 }
1493
1494 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1495 u2 method_index) {
1496 Array<jushort>* inner_class_list = inner_classes();
1497 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1498 int length = inner_class_list->length();
1499 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1500 int index = length - enclosing_method_attribute_size;
1501 inner_class_list->at_put(
1502 index + enclosing_method_class_index_offset, class_index);
1503 inner_class_list->at_put(
1504 index + enclosing_method_method_index_offset, method_index);
1505 }
1506 }
1507
1508 // Lookup or create a jmethodID.
1509 // This code is called by the VMThread and JavaThreads so the
1510 // locking has to be done very carefully to avoid deadlocks
1511 // and/or other cache consistency problems.
1512 //
1513 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1514 size_t idnum = (size_t)method_h->method_idnum();
1515 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1516 size_t length = 0;
1517 jmethodID id = NULL;
1518
1519 // We use a double-check locking idiom here because this cache is
1520 // performance sensitive. In the normal system, this cache only
1521 // transitions from NULL to non-NULL which is safe because we use
1522 // release_set_methods_jmethod_ids() to advertise the new cache.
1523 // A partially constructed cache should never be seen by a racing
1524 // thread. We also use release_store_ptr() to save a new jmethodID
1525 // in the cache so a partially constructed jmethodID should never be
1526 // seen either. Cache reads of existing jmethodIDs proceed without a
1527 // lock, but cache writes of a new jmethodID requires uniqueness and
1528 // creation of the cache itself requires no leaks so a lock is
1529 // generally acquired in those two cases.
1530 //
1531 // If the RedefineClasses() API has been used, then this cache can
1532 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1533 // Cache creation requires no leaks and we require safety between all
1534 // cache accesses and freeing of the old cache so a lock is generally
1535 // acquired when the RedefineClasses() API has been used.
1536
1537 if (jmeths != NULL) {
1538 // the cache already exists
1539 if (!ik_h->idnum_can_increment()) {
1540 // the cache can't grow so we can just get the current values
1541 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1542 } else {
1543 // cache can grow so we have to be more careful
1544 if (Threads::number_of_threads() == 0 ||
1545 SafepointSynchronize::is_at_safepoint()) {
1546 // we're single threaded or at a safepoint - no locking needed
1547 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1548 } else {
1549 MutexLocker ml(JmethodIdCreation_lock);
1550 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1551 }
1552 }
1553 }
1554 // implied else:
1555 // we need to allocate a cache so default length and id values are good
1556
1557 if (jmeths == NULL || // no cache yet
1558 length <= idnum || // cache is too short
1559 id == NULL) { // cache doesn't contain entry
1560
1561 // This function can be called by the VMThread so we have to do all
1562 // things that might block on a safepoint before grabbing the lock.
1563 // Otherwise, we can deadlock with the VMThread or have a cache
1564 // consistency issue. These vars keep track of what we might have
1565 // to free after the lock is dropped.
1566 jmethodID to_dealloc_id = NULL;
1567 jmethodID* to_dealloc_jmeths = NULL;
1568
1569 // may not allocate new_jmeths or use it if we allocate it
1570 jmethodID* new_jmeths = NULL;
1571 if (length <= idnum) {
1572 // allocate a new cache that might be used
1573 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1574 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1575 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1576 // cache size is stored in element[0], other elements offset by one
1577 new_jmeths[0] = (jmethodID)size;
1578 }
1579
1580 // allocate a new jmethodID that might be used
1581 jmethodID new_id = NULL;
1582 if (method_h->is_old() && !method_h->is_obsolete()) {
1583 // The method passed in is old (but not obsolete), we need to use the current version
1584 Method* current_method = ik_h->method_with_idnum((int)idnum);
1585 assert(current_method != NULL, "old and but not obsolete, so should exist");
1586 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1587 } else {
1588 // It is the current version of the method or an obsolete method,
1589 // use the version passed in
1590 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1591 }
1592
1593 if (Threads::number_of_threads() == 0 ||
1594 SafepointSynchronize::is_at_safepoint()) {
1595 // we're single threaded or at a safepoint - no locking needed
1596 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1597 &to_dealloc_id, &to_dealloc_jmeths);
1598 } else {
1599 MutexLocker ml(JmethodIdCreation_lock);
1600 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1601 &to_dealloc_id, &to_dealloc_jmeths);
1602 }
1603
1604 // The lock has been dropped so we can free resources.
1605 // Free up either the old cache or the new cache if we allocated one.
1606 if (to_dealloc_jmeths != NULL) {
1607 FreeHeap(to_dealloc_jmeths);
1608 }
1609 // free up the new ID since it wasn't needed
1610 if (to_dealloc_id != NULL) {
1611 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1612 }
1613 }
1614 return id;
1615 }
1616
1617
1618 // Common code to fetch the jmethodID from the cache or update the
1619 // cache with the new jmethodID. This function should never do anything
1620 // that causes the caller to go to a safepoint or we can deadlock with
1621 // the VMThread or have cache consistency issues.
1622 //
1623 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1624 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1625 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1626 jmethodID** to_dealloc_jmeths_p) {
1627 assert(new_id != NULL, "sanity check");
1628 assert(to_dealloc_id_p != NULL, "sanity check");
1629 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1630 assert(Threads::number_of_threads() == 0 ||
1631 SafepointSynchronize::is_at_safepoint() ||
1632 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1633
1634 // reacquire the cache - we are locked, single threaded or at a safepoint
1635 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1636 jmethodID id = NULL;
1637 size_t length = 0;
1638
1639 if (jmeths == NULL || // no cache yet
1640 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1641 if (jmeths != NULL) {
1642 // copy any existing entries from the old cache
1643 for (size_t index = 0; index < length; index++) {
1644 new_jmeths[index+1] = jmeths[index+1];
1645 }
1646 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1647 }
1648 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1649 } else {
1650 // fetch jmethodID (if any) from the existing cache
1651 id = jmeths[idnum+1];
1652 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1653 }
1654 if (id == NULL) {
1655 // No matching jmethodID in the existing cache or we have a new
1656 // cache or we just grew the cache. This cache write is done here
1657 // by the first thread to win the foot race because a jmethodID
1658 // needs to be unique once it is generally available.
1659 id = new_id;
1660
1661 // The jmethodID cache can be read while unlocked so we have to
1662 // make sure the new jmethodID is complete before installing it
1663 // in the cache.
1664 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1665 } else {
1666 *to_dealloc_id_p = new_id; // save new id for later delete
1667 }
1668 return id;
1669 }
1670
1671
1672 // Common code to get the jmethodID cache length and the jmethodID
1673 // value at index idnum if there is one.
1674 //
1675 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1676 size_t idnum, size_t *length_p, jmethodID* id_p) {
1677 assert(cache != NULL, "sanity check");
1678 assert(length_p != NULL, "sanity check");
1679 assert(id_p != NULL, "sanity check");
1680
1681 // cache size is stored in element[0], other elements offset by one
1682 *length_p = (size_t)cache[0];
1683 if (*length_p <= idnum) { // cache is too short
1684 *id_p = NULL;
1685 } else {
1686 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1687 }
1688 }
1689
1690
1691 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1692 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1693 size_t idnum = (size_t)method->method_idnum();
1694 jmethodID* jmeths = methods_jmethod_ids_acquire();
1695 size_t length; // length assigned as debugging crumb
1696 jmethodID id = NULL;
1697 if (jmeths != NULL && // If there is a cache
1698 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1699 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1700 }
1701 return id;
1702 }
1703
1704
1705 // Cache an itable index
1706 void InstanceKlass::set_cached_itable_index(size_t idnum, int index) {
1707 int* indices = methods_cached_itable_indices_acquire();
1708 int* to_dealloc_indices = NULL;
1709
1710 // We use a double-check locking idiom here because this cache is
1711 // performance sensitive. In the normal system, this cache only
1712 // transitions from NULL to non-NULL which is safe because we use
1713 // release_set_methods_cached_itable_indices() to advertise the
1714 // new cache. A partially constructed cache should never be seen
1715 // by a racing thread. Cache reads and writes proceed without a
1716 // lock, but creation of the cache itself requires no leaks so a
1717 // lock is generally acquired in that case.
1718 //
1719 // If the RedefineClasses() API has been used, then this cache can
1720 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1721 // Cache creation requires no leaks and we require safety between all
1722 // cache accesses and freeing of the old cache so a lock is generally
1723 // acquired when the RedefineClasses() API has been used.
1724
1725 if (indices == NULL || idnum_can_increment()) {
1726 // we need a cache or the cache can grow
1727 MutexLocker ml(JNICachedItableIndex_lock);
1728 // reacquire the cache to see if another thread already did the work
1729 indices = methods_cached_itable_indices_acquire();
1730 size_t length = 0;
1731 // cache size is stored in element[0], other elements offset by one
1732 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1733 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1734 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1, mtClass);
1735 new_indices[0] = (int)size;
1736 // copy any existing entries
1737 size_t i;
1738 for (i = 0; i < length; i++) {
1739 new_indices[i+1] = indices[i+1];
1740 }
1741 // Set all the rest to -1
1742 for (i = length; i < size; i++) {
1743 new_indices[i+1] = -1;
1744 }
1745 if (indices != NULL) {
1746 // We have an old cache to delete so save it for after we
1747 // drop the lock.
1748 to_dealloc_indices = indices;
1749 }
1750 release_set_methods_cached_itable_indices(indices = new_indices);
1751 }
1752
1753 if (idnum_can_increment()) {
1754 // this cache can grow so we have to write to it safely
1755 indices[idnum+1] = index;
1756 }
1757 } else {
1758 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1759 }
1760
1761 if (!idnum_can_increment()) {
1762 // The cache cannot grow and this JNI itable index value does not
1763 // have to be unique like a jmethodID. If there is a race to set it,
1764 // it doesn't matter.
1765 indices[idnum+1] = index;
1766 }
1767
1768 if (to_dealloc_indices != NULL) {
1769 // we allocated a new cache so free the old one
1770 FreeHeap(to_dealloc_indices);
1771 }
1772 }
1773
1774
1775 // Retrieve a cached itable index
1776 int InstanceKlass::cached_itable_index(size_t idnum) {
1777 int* indices = methods_cached_itable_indices_acquire();
1778 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1779 // indices exist and are long enough, retrieve possible cached
1780 return indices[idnum+1];
1781 }
1782 return -1;
1783 }
1784
1785
1786 //
1787 // Walk the list of dependent nmethods searching for nmethods which
1788 // are dependent on the changes that were passed in and mark them for
1789 // deoptimization. Returns the number of nmethods found.
1790 //
1791 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1792 assert_locked_or_safepoint(CodeCache_lock);
1793 int found = 0;
1794 nmethodBucket* b = _dependencies;
1795 while (b != NULL) {
1796 nmethod* nm = b->get_nmethod();
1797 // since dependencies aren't removed until an nmethod becomes a zombie,
1798 // the dependency list may contain nmethods which aren't alive.
1799 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1800 if (TraceDependencies) {
1801 ResourceMark rm;
1802 tty->print_cr("Marked for deoptimization");
1803 tty->print_cr(" context = %s", this->external_name());
1804 changes.print();
1805 nm->print();
1806 nm->print_dependencies();
1807 }
1808 nm->mark_for_deoptimization();
1809 found++;
1810 }
1811 b = b->next();
1812 }
1813 return found;
1814 }
1815
1816
1817 //
1818 // Add an nmethodBucket to the list of dependencies for this nmethod.
1819 // It's possible that an nmethod has multiple dependencies on this klass
1820 // so a count is kept for each bucket to guarantee that creation and
1821 // deletion of dependencies is consistent.
1822 //
1823 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1824 assert_locked_or_safepoint(CodeCache_lock);
1825 nmethodBucket* b = _dependencies;
1826 nmethodBucket* last = NULL;
1827 while (b != NULL) {
1828 if (nm == b->get_nmethod()) {
1829 b->increment();
1830 return;
1831 }
1832 b = b->next();
1833 }
1834 _dependencies = new nmethodBucket(nm, _dependencies);
1835 }
1836
1837
1838 //
1839 // Decrement count of the nmethod in the dependency list and remove
1840 // the bucket competely when the count goes to 0. This method must
1841 // find a corresponding bucket otherwise there's a bug in the
1842 // recording of dependecies.
1843 //
1844 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1845 assert_locked_or_safepoint(CodeCache_lock);
1846 nmethodBucket* b = _dependencies;
1847 nmethodBucket* last = NULL;
1848 while (b != NULL) {
1849 if (nm == b->get_nmethod()) {
1850 if (b->decrement() == 0) {
1851 if (last == NULL) {
1852 _dependencies = b->next();
1853 } else {
1854 last->set_next(b->next());
1855 }
1856 delete b;
1857 }
1858 return;
1859 }
1860 last = b;
1861 b = b->next();
1862 }
1863 #ifdef ASSERT
1864 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1865 nm->print();
1866 #endif // ASSERT
1867 ShouldNotReachHere();
1868 }
1869
1870
1871 #ifndef PRODUCT
1872 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1873 nmethodBucket* b = _dependencies;
1874 int idx = 0;
1875 while (b != NULL) {
1876 nmethod* nm = b->get_nmethod();
1877 tty->print("[%d] count=%d { ", idx++, b->count());
1878 if (!verbose) {
1879 nm->print_on(tty, "nmethod");
1880 tty->print_cr(" } ");
1881 } else {
1882 nm->print();
1883 nm->print_dependencies();
1884 tty->print_cr("--- } ");
1885 }
1886 b = b->next();
1887 }
1888 }
1889
1890
1891 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1892 nmethodBucket* b = _dependencies;
1893 while (b != NULL) {
1894 if (nm == b->get_nmethod()) {
1895 return true;
1896 }
1897 b = b->next();
1898 }
1899 return false;
1900 }
1901 #endif //PRODUCT
1902
1903
1904 // Garbage collection
1905
1906 void InstanceKlass::oops_do(OopClosure* cl) {
1907 Klass::oops_do(cl);
1908
1909 cl->do_oop(adr_protection_domain());
1910 cl->do_oop(adr_signers());
1911 cl->do_oop(adr_init_lock());
1912
1913 // Don't walk the arrays since they are walked from the ClassLoaderData objects.
1914 }
1915
1916 #ifdef ASSERT
1917 template <class T> void assert_is_in(T *p) {
1918 T heap_oop = oopDesc::load_heap_oop(p);
1919 if (!oopDesc::is_null(heap_oop)) {
1920 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1921 assert(Universe::heap()->is_in(o), "should be in heap");
1922 }
1923 }
1924 template <class T> void assert_is_in_closed_subset(T *p) {
1925 T heap_oop = oopDesc::load_heap_oop(p);
1926 if (!oopDesc::is_null(heap_oop)) {
1927 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1928 assert(Universe::heap()->is_in_closed_subset(o),
1929 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1930 }
1931 }
1932 template <class T> void assert_is_in_reserved(T *p) {
1933 T heap_oop = oopDesc::load_heap_oop(p);
1934 if (!oopDesc::is_null(heap_oop)) {
1935 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1936 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1937 }
1938 }
1939 template <class T> void assert_nothing(T *p) {}
1940
1941 #else
1942 template <class T> void assert_is_in(T *p) {}
1943 template <class T> void assert_is_in_closed_subset(T *p) {}
1944 template <class T> void assert_is_in_reserved(T *p) {}
1945 template <class T> void assert_nothing(T *p) {}
1946 #endif // ASSERT
1947
1948 //
1949 // Macros that iterate over areas of oops which are specialized on type of
1950 // oop pointer either narrow or wide, depending on UseCompressedOops
1951 //
1952 // Parameters are:
1953 // T - type of oop to point to (either oop or narrowOop)
1954 // start_p - starting pointer for region to iterate over
1955 // count - number of oops or narrowOops to iterate over
1956 // do_oop - action to perform on each oop (it's arbitrary C code which
1957 // makes it more efficient to put in a macro rather than making
1958 // it a template function)
1959 // assert_fn - assert function which is template function because performance
1960 // doesn't matter when enabled.
1961 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1962 T, start_p, count, do_oop, \
1963 assert_fn) \
1964 { \
1965 T* p = (T*)(start_p); \
1966 T* const end = p + (count); \
1967 while (p < end) { \
1968 (assert_fn)(p); \
1969 do_oop; \
1970 ++p; \
1971 } \
1972 }
1973
1974 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1975 T, start_p, count, do_oop, \
1976 assert_fn) \
1977 { \
1978 T* const start = (T*)(start_p); \
1979 T* p = start + (count); \
1980 while (start < p) { \
1981 --p; \
1982 (assert_fn)(p); \
1983 do_oop; \
1984 } \
1985 }
1986
1987 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1988 T, start_p, count, low, high, \
1989 do_oop, assert_fn) \
1990 { \
1991 T* const l = (T*)(low); \
1992 T* const h = (T*)(high); \
1993 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1994 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1995 "bounded region must be properly aligned"); \
1996 T* p = (T*)(start_p); \
1997 T* end = p + (count); \
1998 if (p < l) p = l; \
1999 if (end > h) end = h; \
2000 while (p < end) { \
2001 (assert_fn)(p); \
2002 do_oop; \
2003 ++p; \
2004 } \
2005 }
2006
2007
2008 // The following macros call specialized macros, passing either oop or
2009 // narrowOop as the specialization type. These test the UseCompressedOops
2010 // flag.
2011 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2012 { \
2013 /* Compute oopmap block range. The common case \
2014 is nonstatic_oop_map_size == 1. */ \
2015 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2016 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2017 if (UseCompressedOops) { \
2018 while (map < end_map) { \
2019 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2020 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2021 do_oop, assert_fn) \
2022 ++map; \
2023 } \
2024 } else { \
2025 while (map < end_map) { \
2026 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2027 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2028 do_oop, assert_fn) \
2029 ++map; \
2030 } \
2031 } \
2032 }
2033
2034 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2035 { \
2036 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2037 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2038 if (UseCompressedOops) { \
2039 while (start_map < map) { \
2040 --map; \
2041 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2042 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2043 do_oop, assert_fn) \
2044 } \
2045 } else { \
2046 while (start_map < map) { \
2047 --map; \
2048 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2049 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2050 do_oop, assert_fn) \
2051 } \
2052 } \
2053 }
2054
2055 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2056 assert_fn) \
2057 { \
2058 /* Compute oopmap block range. The common case is \
2059 nonstatic_oop_map_size == 1, so we accept the \
2060 usually non-existent extra overhead of examining \
2061 all the maps. */ \
2062 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2063 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2064 if (UseCompressedOops) { \
2065 while (map < end_map) { \
2066 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2067 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2068 low, high, \
2069 do_oop, assert_fn) \
2070 ++map; \
2071 } \
2072 } else { \
2073 while (map < end_map) { \
2074 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2075 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2076 low, high, \
2077 do_oop, assert_fn) \
2078 ++map; \
2079 } \
2080 } \
2081 }
2082
2083 void InstanceKlass::oop_follow_contents(oop obj) {
2084 assert(obj != NULL, "can't follow the content of NULL object");
2085 MarkSweep::follow_klass(obj->klass());
2086 InstanceKlass_OOP_MAP_ITERATE( \
2087 obj, \
2088 MarkSweep::mark_and_push(p), \
2089 assert_is_in_closed_subset)
2090 }
2091
2092 #if INCLUDE_ALL_GCS
2093 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2094 oop obj) {
2095 assert(obj != NULL, "can't follow the content of NULL object");
2096 PSParallelCompact::follow_klass(cm, obj->klass());
2097 // Only mark the header and let the scan of the meta-data mark
2098 // everything else.
2099 InstanceKlass_OOP_MAP_ITERATE( \
2100 obj, \
2101 PSParallelCompact::mark_and_push(cm, p), \
2102 assert_is_in)
2103 }
2104 #endif // INCLUDE_ALL_GCS
2105
2106 // closure's do_metadata() method dictates whether the given closure should be
2107 // applied to the klass ptr in the object header.
2108
2109 #define if_do_metadata_checked(closure, nv_suffix) \
2110 /* Make sure the non-virtual and the virtual versions match. */ \
2111 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2112 "Inconsistency in do_metadata"); \
2113 if (closure->do_metadata##nv_suffix())
2114
2115 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2116 \
2117 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2118 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2119 /* header */ \
2120 if_do_metadata_checked(closure, nv_suffix) { \
2121 closure->do_klass##nv_suffix(obj->klass()); \
2122 } \
2123 InstanceKlass_OOP_MAP_ITERATE( \
2124 obj, \
2125 SpecializationStats:: \
2126 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2127 (closure)->do_oop##nv_suffix(p), \
2128 assert_is_in_closed_subset) \
2129 return size_helper(); \
2130 }
2131
2132 #if INCLUDE_ALL_GCS
2133 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2134 \
2135 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2136 OopClosureType* closure) { \
2137 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2138 /* header */ \
2139 if_do_metadata_checked(closure, nv_suffix) { \
2140 closure->do_klass##nv_suffix(obj->klass()); \
2141 } \
2142 /* instance variables */ \
2143 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2144 obj, \
2145 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2146 (closure)->do_oop##nv_suffix(p), \
2147 assert_is_in_closed_subset) \
2148 return size_helper(); \
2149 }
2150 #endif // INCLUDE_ALL_GCS
2151
2152 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2153 \
2154 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2155 OopClosureType* closure, \
2156 MemRegion mr) { \
2157 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2158 if_do_metadata_checked(closure, nv_suffix) { \
2159 if (mr.contains(obj)) { \
2160 closure->do_klass##nv_suffix(obj->klass()); \
2161 } \
2162 } \
2163 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2164 obj, mr.start(), mr.end(), \
2165 (closure)->do_oop##nv_suffix(p), \
2166 assert_is_in_closed_subset) \
2167 return size_helper(); \
2168 }
2169
2170 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2171 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2172 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2173 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2174 #if INCLUDE_ALL_GCS
2175 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2176 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2177 #endif // INCLUDE_ALL_GCS
2178
2179 int InstanceKlass::oop_adjust_pointers(oop obj) {
2180 int size = size_helper();
2181 InstanceKlass_OOP_MAP_ITERATE( \
2182 obj, \
2183 MarkSweep::adjust_pointer(p), \
2184 assert_is_in)
2185 MarkSweep::adjust_klass(obj->klass());
2186 return size;
2187 }
2188
2189 #if INCLUDE_ALL_GCS
2190 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2191 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2192 obj, \
2193 if (PSScavenge::should_scavenge(p)) { \
2194 pm->claim_or_forward_depth(p); \
2195 }, \
2196 assert_nothing )
2197 }
2198
2199 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2200 int size = size_helper();
2201 InstanceKlass_OOP_MAP_ITERATE( \
2202 obj, \
2203 PSParallelCompact::adjust_pointer(p), \
2204 assert_is_in)
2205 obj->update_header(cm);
2206 return size;
2207 }
2208
2209 #endif // INCLUDE_ALL_GCS
2210
2211 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2212 assert(is_loader_alive(is_alive), "this klass should be live");
2213 if (is_interface()) {
2214 if (ClassUnloading) {
2215 Klass* impl = implementor();
2216 if (impl != NULL) {
2217 if (!impl->is_loader_alive(is_alive)) {
2218 // remove this guy
2219 Klass** klass = adr_implementor();
2220 assert(klass != NULL, "null klass");
2221 if (klass != NULL) {
2222 *klass = NULL;
2223 }
2224 }
2225 }
2226 }
2227 }
2228 }
2229
2230 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2231 #ifdef COMPILER2
2232 // Currently only used by C2.
2233 for (int m = 0; m < methods()->length(); m++) {
2234 MethodData* mdo = methods()->at(m)->method_data();
2235 if (mdo != NULL) {
2236 for (ProfileData* data = mdo->first_data();
2237 mdo->is_valid(data);
2238 data = mdo->next_data(data)) {
2239 data->clean_weak_klass_links(is_alive);
2240 }
2241 }
2242 }
2243 #else
2244 #ifdef ASSERT
2245 // Verify that we haven't started to use MDOs for C1.
2246 for (int m = 0; m < methods()->length(); m++) {
2247 MethodData* mdo = methods()->at(m)->method_data();
2248 assert(mdo == NULL, "Didn't expect C1 to use MDOs");
2249 }
2250 #endif // ASSERT
2251 #endif // !COMPILER2
2252 }
2253
2254
2255 static void remove_unshareable_in_class(Klass* k) {
2256 // remove klass's unshareable info
2257 k->remove_unshareable_info();
2258 }
2259
2260 void InstanceKlass::remove_unshareable_info() {
2261 Klass::remove_unshareable_info();
2262 // Unlink the class
2263 if (is_linked()) {
2264 unlink_class();
2265 }
2266 init_implementor();
2267
2268 constants()->remove_unshareable_info();
2269
2270 for (int i = 0; i < methods()->length(); i++) {
2271 Method* m = methods()->at(i);
2272 m->remove_unshareable_info();
2273 }
2274
2275 // Need to reinstate when reading back the class.
2276 set_init_lock(NULL);
2277
2278 // do array classes also.
2279 array_klasses_do(remove_unshareable_in_class);
2280 }
2281
2282 void restore_unshareable_in_class(Klass* k, TRAPS) {
2283 k->restore_unshareable_info(CHECK);
2284 }
2285
2286 void InstanceKlass::restore_unshareable_info(TRAPS) {
2287 Klass::restore_unshareable_info(CHECK);
2288 instanceKlassHandle ik(THREAD, this);
2289
2290 Array<Method*>* methods = ik->methods();
2291 int num_methods = methods->length();
2292 for (int index2 = 0; index2 < num_methods; ++index2) {
2293 methodHandle m(THREAD, methods->at(index2));
2294 m()->link_method(m, CHECK);
2295 // restore method's vtable by calling a virtual function
2296 m->restore_vtable();
2297 }
2298 if (JvmtiExport::has_redefined_a_class()) {
2299 // Reinitialize vtable because RedefineClasses may have changed some
2300 // entries in this vtable for super classes so the CDS vtable might
2301 // point to old or obsolete entries. RedefineClasses doesn't fix up
2302 // vtables in the shared system dictionary, only the main one.
2303 // It also redefines the itable too so fix that too.
2304 ResourceMark rm(THREAD);
2305 ik->vtable()->initialize_vtable(false, CHECK);
2306 ik->itable()->initialize_itable(false, CHECK);
2307 }
2308
2309 // Allocate a simple java object for a lock.
2310 // This needs to be a java object because during class initialization
2311 // it can be held across a java call.
2312 typeArrayOop r = oopFactory::new_typeArray(T_INT, 0, CHECK);
2313 Handle h(THREAD, (oop)r);
2314 ik->set_init_lock(h());
2315
2316 // restore constant pool resolved references
2317 ik->constants()->restore_unshareable_info(CHECK);
2318
2319 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2320 }
2321
2322 static void clear_all_breakpoints(Method* m) {
2323 m->clear_all_breakpoints();
2324 }
2325
2326 void InstanceKlass::release_C_heap_structures() {
2327 // Deallocate oop map cache
2328 if (_oop_map_cache != NULL) {
2329 delete _oop_map_cache;
2330 _oop_map_cache = NULL;
2331 }
2332
2333 // Deallocate JNI identifiers for jfieldIDs
2334 JNIid::deallocate(jni_ids());
2335 set_jni_ids(NULL);
2336
2337 jmethodID* jmeths = methods_jmethod_ids_acquire();
2338 if (jmeths != (jmethodID*)NULL) {
2339 release_set_methods_jmethod_ids(NULL);
2340 FreeHeap(jmeths);
2341 }
2342
2343 int* indices = methods_cached_itable_indices_acquire();
2344 if (indices != (int*)NULL) {
2345 release_set_methods_cached_itable_indices(NULL);
2346 FreeHeap(indices);
2347 }
2348
2349 // release dependencies
2350 nmethodBucket* b = _dependencies;
2351 _dependencies = NULL;
2352 while (b != NULL) {
2353 nmethodBucket* next = b->next();
2354 delete b;
2355 b = next;
2356 }
2357
2358 // Deallocate breakpoint records
2359 if (breakpoints() != 0x0) {
2360 methods_do(clear_all_breakpoints);
2361 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2362 }
2363
2364 // deallocate information about previous versions
2365 if (_previous_versions != NULL) {
2366 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2367 PreviousVersionNode * pv_node = _previous_versions->at(i);
2368 delete pv_node;
2369 }
2370 delete _previous_versions;
2371 _previous_versions = NULL;
2372 }
2373
2374 // deallocate the cached class file
2375 if (_cached_class_file_bytes != NULL) {
2376 os::free(_cached_class_file_bytes, mtClass);
2377 _cached_class_file_bytes = NULL;
2378 _cached_class_file_len = 0;
2379 }
2380
2381 // Decrement symbol reference counts associated with the unloaded class.
2382 if (_name != NULL) _name->decrement_refcount();
2383 // unreference array name derived from this class name (arrays of an unloaded
2384 // class can't be referenced anymore).
2385 if (_array_name != NULL) _array_name->decrement_refcount();
2386 if (_source_file_name != NULL) _source_file_name->decrement_refcount();
2387 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2388
2389 assert(_total_instanceKlass_count >= 1, "Sanity check");
2390 Atomic::dec(&_total_instanceKlass_count);
2391 }
2392
2393 void InstanceKlass::set_source_file_name(Symbol* n) {
2394 _source_file_name = n;
2395 if (_source_file_name != NULL) _source_file_name->increment_refcount();
2396 }
2397
2398 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2399 if (array == NULL) {
2400 _source_debug_extension = NULL;
2401 } else {
2402 // Adding one to the attribute length in order to store a null terminator
2403 // character could cause an overflow because the attribute length is
2404 // already coded with an u4 in the classfile, but in practice, it's
2405 // unlikely to happen.
2406 assert((length+1) > length, "Overflow checking");
2407 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2408 for (int i = 0; i < length; i++) {
2409 sde[i] = array[i];
2410 }
2411 sde[length] = '\0';
2412 _source_debug_extension = sde;
2413 }
2414 }
2415
2416 address InstanceKlass::static_field_addr(int offset) {
2417 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror());
2418 }
2419
2420
2421 const char* InstanceKlass::signature_name() const {
2422 const char* src = (const char*) (name()->as_C_string());
2423 const int src_length = (int)strlen(src);
2424 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
2425 int src_index = 0;
2426 int dest_index = 0;
2427 dest[dest_index++] = 'L';
2428 while (src_index < src_length) {
2429 dest[dest_index++] = src[src_index++];
2430 }
2431 dest[dest_index++] = ';';
2432 dest[dest_index] = '\0';
2433 return dest;
2434 }
2435
2436 // different verisons of is_same_class_package
2437 bool InstanceKlass::is_same_class_package(Klass* class2) {
2438 Klass* class1 = this;
2439 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2440 Symbol* classname1 = class1->name();
2441
2442 if (class2->oop_is_objArray()) {
2443 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2444 }
2445 oop classloader2;
2446 if (class2->oop_is_instance()) {
2447 classloader2 = InstanceKlass::cast(class2)->class_loader();
2448 } else {
2449 assert(class2->oop_is_typeArray(), "should be type array");
2450 classloader2 = NULL;
2451 }
2452 Symbol* classname2 = class2->name();
2453
2454 return InstanceKlass::is_same_class_package(classloader1, classname1,
2455 classloader2, classname2);
2456 }
2457
2458 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2459 Klass* class1 = this;
2460 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2461 Symbol* classname1 = class1->name();
2462
2463 return InstanceKlass::is_same_class_package(classloader1, classname1,
2464 classloader2, classname2);
2465 }
2466
2467 // return true if two classes are in the same package, classloader
2468 // and classname information is enough to determine a class's package
2469 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2470 oop class_loader2, Symbol* class_name2) {
2471 if (class_loader1 != class_loader2) {
2472 return false;
2473 } else if (class_name1 == class_name2) {
2474 return true; // skip painful bytewise comparison
2475 } else {
2476 ResourceMark rm;
2477
2478 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2479 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2480 // Otherwise, we just compare jbyte values between the strings.
2481 const jbyte *name1 = class_name1->base();
2482 const jbyte *name2 = class_name2->base();
2483
2484 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2485 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2486
2487 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2488 // One of the two doesn't have a package. Only return true
2489 // if the other one also doesn't have a package.
2490 return last_slash1 == last_slash2;
2491 } else {
2492 // Skip over '['s
2493 if (*name1 == '[') {
2494 do {
2495 name1++;
2496 } while (*name1 == '[');
2497 if (*name1 != 'L') {
2498 // Something is terribly wrong. Shouldn't be here.
2499 return false;
2500 }
2501 }
2502 if (*name2 == '[') {
2503 do {
2504 name2++;
2505 } while (*name2 == '[');
2506 if (*name2 != 'L') {
2507 // Something is terribly wrong. Shouldn't be here.
2508 return false;
2509 }
2510 }
2511
2512 // Check that package part is identical
2513 int length1 = last_slash1 - name1;
2514 int length2 = last_slash2 - name2;
2515
2516 return UTF8::equal(name1, length1, name2, length2);
2517 }
2518 }
2519 }
2520
2521 // Returns true iff super_method can be overridden by a method in targetclassname
2522 // See JSL 3rd edition 8.4.6.1
2523 // Assumes name-signature match
2524 // "this" is InstanceKlass of super_method which must exist
2525 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2526 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2527 // Private methods can not be overridden
2528 if (super_method->is_private()) {
2529 return false;
2530 }
2531 // If super method is accessible, then override
2532 if ((super_method->is_protected()) ||
2533 (super_method->is_public())) {
2534 return true;
2535 }
2536 // Package-private methods are not inherited outside of package
2537 assert(super_method->is_package_private(), "must be package private");
2538 return(is_same_class_package(targetclassloader(), targetclassname));
2539 }
2540
2541 /* defined for now in jvm.cpp, for historical reasons *--
2542 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2543 Symbol*& simple_name_result, TRAPS) {
2544 ...
2545 }
2546 */
2547
2548 // tell if two classes have the same enclosing class (at package level)
2549 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2550 Klass* class2_oop, TRAPS) {
2551 if (class2_oop == class1()) return true;
2552 if (!class2_oop->oop_is_instance()) return false;
2553 instanceKlassHandle class2(THREAD, class2_oop);
2554
2555 // must be in same package before we try anything else
2556 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2557 return false;
2558
2559 // As long as there is an outer1.getEnclosingClass,
2560 // shift the search outward.
2561 instanceKlassHandle outer1 = class1;
2562 for (;;) {
2563 // As we walk along, look for equalities between outer1 and class2.
2564 // Eventually, the walks will terminate as outer1 stops
2565 // at the top-level class around the original class.
2566 bool ignore_inner_is_member;
2567 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2568 CHECK_false);
2569 if (next == NULL) break;
2570 if (next == class2()) return true;
2571 outer1 = instanceKlassHandle(THREAD, next);
2572 }
2573
2574 // Now do the same for class2.
2575 instanceKlassHandle outer2 = class2;
2576 for (;;) {
2577 bool ignore_inner_is_member;
2578 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2579 CHECK_false);
2580 if (next == NULL) break;
2581 // Might as well check the new outer against all available values.
2582 if (next == class1()) return true;
2583 if (next == outer1()) return true;
2584 outer2 = instanceKlassHandle(THREAD, next);
2585 }
2586
2587 // If by this point we have not found an equality between the
2588 // two classes, we know they are in separate package members.
2589 return false;
2590 }
2591
2592
2593 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2594 jint access = access_flags().as_int();
2595
2596 // But check if it happens to be member class.
2597 instanceKlassHandle ik(THREAD, this);
2598 InnerClassesIterator iter(ik);
2599 for (; !iter.done(); iter.next()) {
2600 int ioff = iter.inner_class_info_index();
2601 // Inner class attribute can be zero, skip it.
2602 // Strange but true: JVM spec. allows null inner class refs.
2603 if (ioff == 0) continue;
2604
2605 // only look at classes that are already loaded
2606 // since we are looking for the flags for our self.
2607 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2608 if ((ik->name() == inner_name)) {
2609 // This is really a member class.
2610 access = iter.inner_access_flags();
2611 break;
2612 }
2613 }
2614 // Remember to strip ACC_SUPER bit
2615 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2616 }
2617
2618 jint InstanceKlass::jvmti_class_status() const {
2619 jint result = 0;
2620
2621 if (is_linked()) {
2622 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2623 }
2624
2625 if (is_initialized()) {
2626 assert(is_linked(), "Class status is not consistent");
2627 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2628 }
2629 if (is_in_error_state()) {
2630 result |= JVMTI_CLASS_STATUS_ERROR;
2631 }
2632 return result;
2633 }
2634
2635 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2636 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2637 int method_table_offset_in_words = ioe->offset()/wordSize;
2638 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2639 / itableOffsetEntry::size();
2640
2641 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2642 // If the interface isn't implemented by the receiver class,
2643 // the VM should throw IncompatibleClassChangeError.
2644 if (cnt >= nof_interfaces) {
2645 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2646 }
2647
2648 Klass* ik = ioe->interface_klass();
2649 if (ik == holder) break;
2650 }
2651
2652 itableMethodEntry* ime = ioe->first_method_entry(this);
2653 Method* m = ime[index].method();
2654 if (m == NULL) {
2655 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2656 }
2657 return m;
2658 }
2659
2660 // On-stack replacement stuff
2661 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2662 // only one compilation can be active
2663 NEEDS_CLEANUP
2664 // This is a short non-blocking critical region, so the no safepoint check is ok.
2665 OsrList_lock->lock_without_safepoint_check();
2666 assert(n->is_osr_method(), "wrong kind of nmethod");
2667 n->set_osr_link(osr_nmethods_head());
2668 set_osr_nmethods_head(n);
2669 // Raise the highest osr level if necessary
2670 if (TieredCompilation) {
2671 Method* m = n->method();
2672 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2673 }
2674 // Remember to unlock again
2675 OsrList_lock->unlock();
2676
2677 // Get rid of the osr methods for the same bci that have lower levels.
2678 if (TieredCompilation) {
2679 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2680 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2681 if (inv != NULL && inv->is_in_use()) {
2682 inv->make_not_entrant();
2683 }
2684 }
2685 }
2686 }
2687
2688
2689 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2690 // This is a short non-blocking critical region, so the no safepoint check is ok.
2691 OsrList_lock->lock_without_safepoint_check();
2692 assert(n->is_osr_method(), "wrong kind of nmethod");
2693 nmethod* last = NULL;
2694 nmethod* cur = osr_nmethods_head();
2695 int max_level = CompLevel_none; // Find the max comp level excluding n
2696 Method* m = n->method();
2697 // Search for match
2698 while(cur != NULL && cur != n) {
2699 if (TieredCompilation) {
2700 // Find max level before n
2701 max_level = MAX2(max_level, cur->comp_level());
2702 }
2703 last = cur;
2704 cur = cur->osr_link();
2705 }
2706 nmethod* next = NULL;
2707 if (cur == n) {
2708 next = cur->osr_link();
2709 if (last == NULL) {
2710 // Remove first element
2711 set_osr_nmethods_head(next);
2712 } else {
2713 last->set_osr_link(next);
2714 }
2715 }
2716 n->set_osr_link(NULL);
2717 if (TieredCompilation) {
2718 cur = next;
2719 while (cur != NULL) {
2720 // Find max level after n
2721 max_level = MAX2(max_level, cur->comp_level());
2722 cur = cur->osr_link();
2723 }
2724 m->set_highest_osr_comp_level(max_level);
2725 }
2726 // Remember to unlock again
2727 OsrList_lock->unlock();
2728 }
2729
2730 nmethod* InstanceKlass::lookup_osr_nmethod(Method* const m, int bci, int comp_level, bool match_level) const {
2731 // This is a short non-blocking critical region, so the no safepoint check is ok.
2732 OsrList_lock->lock_without_safepoint_check();
2733 nmethod* osr = osr_nmethods_head();
2734 nmethod* best = NULL;
2735 while (osr != NULL) {
2736 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2737 // There can be a time when a c1 osr method exists but we are waiting
2738 // for a c2 version. When c2 completes its osr nmethod we will trash
2739 // the c1 version and only be able to find the c2 version. However
2740 // while we overflow in the c1 code at back branches we don't want to
2741 // try and switch to the same code as we are already running
2742
2743 if (osr->method() == m &&
2744 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2745 if (match_level) {
2746 if (osr->comp_level() == comp_level) {
2747 // Found a match - return it.
2748 OsrList_lock->unlock();
2749 return osr;
2750 }
2751 } else {
2752 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2753 if (osr->comp_level() == CompLevel_highest_tier) {
2754 // Found the best possible - return it.
2755 OsrList_lock->unlock();
2756 return osr;
2757 }
2758 best = osr;
2759 }
2760 }
2761 }
2762 osr = osr->osr_link();
2763 }
2764 OsrList_lock->unlock();
2765 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2766 return best;
2767 }
2768 return NULL;
2769 }
2770
2771 // -----------------------------------------------------------------------------------------------------
2772 // Printing
2773
2774 #ifndef PRODUCT
2775
2776 #define BULLET " - "
2777
2778 static const char* state_names[] = {
2779 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2780 };
2781
2782 void InstanceKlass::print_on(outputStream* st) const {
2783 assert(is_klass(), "must be klass");
2784 Klass::print_on(st);
2785
2786 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2787 st->print(BULLET"klass size: %d", size()); st->cr();
2788 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2789 st->print(BULLET"state: "); st->print_cr(state_names[_init_state]);
2790 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2791 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2792 st->print(BULLET"sub: ");
2793 Klass* sub = subklass();
2794 int n;
2795 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2796 if (n < MaxSubklassPrintSize) {
2797 sub->print_value_on(st);
2798 st->print(" ");
2799 }
2800 }
2801 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2802 st->cr();
2803
2804 if (is_interface()) {
2805 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2806 if (nof_implementors() == 1) {
2807 st->print_cr(BULLET"implementor: ");
2808 st->print(" ");
2809 implementor()->print_value_on(st);
2810 st->cr();
2811 }
2812 }
2813
2814 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2815 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2816 if (Verbose) {
2817 Array<Method*>* method_array = methods();
2818 for(int i = 0; i < method_array->length(); i++) {
2819 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2820 }
2821 }
2822 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2823 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2824 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2825 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2826 if (class_loader_data() != NULL) {
2827 st->print(BULLET"class loader data: ");
2828 class_loader_data()->print_value_on(st);
2829 st->cr();
2830 }
2831 st->print(BULLET"protection domain: "); ((InstanceKlass*)this)->protection_domain()->print_value_on(st); st->cr();
2832 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2833 st->print(BULLET"signers: "); signers()->print_value_on(st); st->cr();
2834 st->print(BULLET"init_lock: "); ((oop)_init_lock)->print_value_on(st); st->cr();
2835 if (source_file_name() != NULL) {
2836 st->print(BULLET"source file: ");
2837 source_file_name()->print_value_on(st);
2838 st->cr();
2839 }
2840 if (source_debug_extension() != NULL) {
2841 st->print(BULLET"source debug extension: ");
2842 st->print("%s", source_debug_extension());
2843 st->cr();
2844 }
2845 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2846 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2847 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2848 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2849 {
2850 ResourceMark rm;
2851 // PreviousVersionInfo objects returned via PreviousVersionWalker
2852 // contain a GrowableArray of handles. We have to clean up the
2853 // GrowableArray _after_ the PreviousVersionWalker destructor
2854 // has destroyed the handles.
2855 {
2856 bool have_pv = false;
2857 PreviousVersionWalker pvw((InstanceKlass*)this);
2858 for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
2859 pv_info != NULL; pv_info = pvw.next_previous_version()) {
2860 if (!have_pv)
2861 st->print(BULLET"previous version: ");
2862 have_pv = true;
2863 pv_info->prev_constant_pool_handle()()->print_value_on(st);
2864 }
2865 if (have_pv) st->cr();
2866 } // pvw is cleaned up
2867 } // rm is cleaned up
2868
2869 if (generic_signature() != NULL) {
2870 st->print(BULLET"generic signature: ");
2871 generic_signature()->print_value_on(st);
2872 st->cr();
2873 }
2874 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2875 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2876 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2877 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2878 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2879 FieldPrinter print_static_field(st);
2880 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2881 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2882 FieldPrinter print_nonstatic_field(st);
2883 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2884
2885 st->print(BULLET"non-static oop maps: ");
2886 OopMapBlock* map = start_of_nonstatic_oop_maps();
2887 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2888 while (map < end_map) {
2889 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2890 map++;
2891 }
2892 st->cr();
2893 }
2894
2895 #endif //PRODUCT
2896
2897 void InstanceKlass::print_value_on(outputStream* st) const {
2898 assert(is_klass(), "must be klass");
2899 name()->print_value_on(st);
2900 }
2901
2902 #ifndef PRODUCT
2903
2904 void FieldPrinter::do_field(fieldDescriptor* fd) {
2905 _st->print(BULLET);
2906 if (_obj == NULL) {
2907 fd->print_on(_st);
2908 _st->cr();
2909 } else {
2910 fd->print_on_for(_st, _obj);
2911 _st->cr();
2912 }
2913 }
2914
2915
2916 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2917 Klass::oop_print_on(obj, st);
2918
2919 if (this == SystemDictionary::String_klass()) {
2920 typeArrayOop value = java_lang_String::value(obj);
2921 juint offset = java_lang_String::offset(obj);
2922 juint length = java_lang_String::length(obj);
2923 if (value != NULL &&
2924 value->is_typeArray() &&
2925 offset <= (juint) value->length() &&
2926 offset + length <= (juint) value->length()) {
2927 st->print(BULLET"string: ");
2928 Handle h_obj(obj);
2929 java_lang_String::print(h_obj, st);
2930 st->cr();
2931 if (!WizardMode) return; // that is enough
2932 }
2933 }
2934
2935 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2936 FieldPrinter print_field(st, obj);
2937 do_nonstatic_fields(&print_field);
2938
2939 if (this == SystemDictionary::Class_klass()) {
2940 st->print(BULLET"signature: ");
2941 java_lang_Class::print_signature(obj, st);
2942 st->cr();
2943 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2944 st->print(BULLET"fake entry for mirror: ");
2945 mirrored_klass->print_value_on_maybe_null(st);
2946 st->cr();
2947 Klass* array_klass = java_lang_Class::array_klass(obj);
2948 st->print(BULLET"fake entry for array: ");
2949 array_klass->print_value_on_maybe_null(st);
2950 st->cr();
2951 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2952 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2953 Klass* real_klass = java_lang_Class::as_Klass(obj);
2954 if (real_klass != NULL && real_klass->oop_is_instance()) {
2955 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2956 }
2957 } else if (this == SystemDictionary::MethodType_klass()) {
2958 st->print(BULLET"signature: ");
2959 java_lang_invoke_MethodType::print_signature(obj, st);
2960 st->cr();
2961 }
2962 }
2963
2964 #endif //PRODUCT
2965
2966 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2967 st->print("a ");
2968 name()->print_value_on(st);
2969 obj->print_address_on(st);
2970 if (this == SystemDictionary::String_klass()
2971 && java_lang_String::value(obj) != NULL) {
2972 ResourceMark rm;
2973 int len = java_lang_String::length(obj);
2974 int plen = (len < 24 ? len : 12);
2975 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2976 st->print(" = \"%s\"", str);
2977 if (len > plen)
2978 st->print("...[%d]", len);
2979 } else if (this == SystemDictionary::Class_klass()) {
2980 Klass* k = java_lang_Class::as_Klass(obj);
2981 st->print(" = ");
2982 if (k != NULL) {
2983 k->print_value_on(st);
2984 } else {
2985 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2986 st->print("%s", tname ? tname : "type?");
2987 }
2988 } else if (this == SystemDictionary::MethodType_klass()) {
2989 st->print(" = ");
2990 java_lang_invoke_MethodType::print_signature(obj, st);
2991 } else if (java_lang_boxing_object::is_instance(obj)) {
2992 st->print(" = ");
2993 java_lang_boxing_object::print(obj, st);
2994 } else if (this == SystemDictionary::LambdaForm_klass()) {
2995 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2996 if (vmentry != NULL) {
2997 st->print(" => ");
2998 vmentry->print_value_on(st);
2999 }
3000 } else if (this == SystemDictionary::MemberName_klass()) {
3001 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3002 if (vmtarget != NULL) {
3003 st->print(" = ");
3004 vmtarget->print_value_on(st);
3005 } else {
3006 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3007 st->print(".");
3008 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3009 }
3010 }
3011 }
3012
3013 const char* InstanceKlass::internal_name() const {
3014 return external_name();
3015 }
3016
3017 #if INCLUDE_SERVICES
3018 // Size Statistics
3019 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3020 Klass::collect_statistics(sz);
3021
3022 sz->_inst_size = HeapWordSize * size_helper();
3023 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3024 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3025 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3026 ((is_interface() || is_anonymous()) ?
3027 align_object_offset(nonstatic_oop_map_size()) :
3028 nonstatic_oop_map_size());
3029
3030 int n = 0;
3031 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3032 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3033 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3034 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3035 n += (sz->_signers_bytes = sz->count_array(signers()));
3036 n += (sz->_fields_bytes = sz->count_array(fields()));
3037 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3038 sz->_ro_bytes += n;
3039
3040 const ConstantPool* cp = constants();
3041 if (cp) {
3042 cp->collect_statistics(sz);
3043 }
3044
3045 const Annotations* anno = annotations();
3046 if (anno) {
3047 anno->collect_statistics(sz);
3048 }
3049
3050 const Array<Method*>* methods_array = methods();
3051 if (methods()) {
3052 for (int i = 0; i < methods_array->length(); i++) {
3053 Method* method = methods_array->at(i);
3054 if (method) {
3055 sz->_method_count ++;
3056 method->collect_statistics(sz);
3057 }
3058 }
3059 }
3060 }
3061 #endif // INCLUDE_SERVICES
3062
3063 // Verification
3064
3065 class VerifyFieldClosure: public OopClosure {
3066 protected:
3067 template <class T> void do_oop_work(T* p) {
3068 oop obj = oopDesc::load_decode_heap_oop(p);
3069 if (!obj->is_oop_or_null()) {
3070 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3071 Universe::print();
3072 guarantee(false, "boom");
3073 }
3074 }
3075 public:
3076 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3077 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3078 };
3079
3080 void InstanceKlass::verify_on(outputStream* st) {
3081 Klass::verify_on(st);
3082 Thread *thread = Thread::current();
3083
3084 #ifndef PRODUCT
3085 // Avoid redundant verifies
3086 if (_verify_count == Universe::verify_count()) return;
3087 _verify_count = Universe::verify_count();
3088 #endif
3089 // Verify that klass is present in SystemDictionary
3090 if (is_loaded() && !is_anonymous()) {
3091 Symbol* h_name = name();
3092 SystemDictionary::verify_obj_klass_present(h_name, class_loader_data());
3093 }
3094
3095 // Verify static fields
3096 VerifyFieldClosure blk;
3097
3098 // Verify vtables
3099 if (is_linked()) {
3100 ResourceMark rm(thread);
3101 // $$$ This used to be done only for m/s collections. Doing it
3102 // always seemed a valid generalization. (DLD -- 6/00)
3103 vtable()->verify(st);
3104 }
3105
3106 // Verify first subklass
3107 if (subklass_oop() != NULL) {
3108 guarantee(subklass_oop()->is_metadata(), "should be in metaspace");
3109 guarantee(subklass_oop()->is_klass(), "should be klass");
3110 }
3111
3112 // Verify siblings
3113 Klass* super = this->super();
3114 Klass* sib = next_sibling();
3115 if (sib != NULL) {
3116 if (sib == this) {
3117 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3118 }
3119
3120 guarantee(sib->is_metadata(), "should be in metaspace");
3121 guarantee(sib->is_klass(), "should be klass");
3122 guarantee(sib->super() == super, "siblings should have same superklass");
3123 }
3124
3125 // Verify implementor fields
3126 Klass* im = implementor();
3127 if (im != NULL) {
3128 guarantee(is_interface(), "only interfaces should have implementor set");
3129 guarantee(im->is_klass(), "should be klass");
3130 guarantee(!im->is_interface() || im == this,
3131 "implementors cannot be interfaces");
3132 }
3133
3134 // Verify local interfaces
3135 if (local_interfaces()) {
3136 Array<Klass*>* local_interfaces = this->local_interfaces();
3137 for (int j = 0; j < local_interfaces->length(); j++) {
3138 Klass* e = local_interfaces->at(j);
3139 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3140 }
3141 }
3142
3143 // Verify transitive interfaces
3144 if (transitive_interfaces() != NULL) {
3145 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3146 for (int j = 0; j < transitive_interfaces->length(); j++) {
3147 Klass* e = transitive_interfaces->at(j);
3148 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3149 }
3150 }
3151
3152 // Verify methods
3153 if (methods() != NULL) {
3154 Array<Method*>* methods = this->methods();
3155 for (int j = 0; j < methods->length(); j++) {
3156 guarantee(methods->at(j)->is_metadata(), "should be in metaspace");
3157 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3158 }
3159 for (int j = 0; j < methods->length() - 1; j++) {
3160 Method* m1 = methods->at(j);
3161 Method* m2 = methods->at(j + 1);
3162 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3163 }
3164 }
3165
3166 // Verify method ordering
3167 if (method_ordering() != NULL) {
3168 Array<int>* method_ordering = this->method_ordering();
3169 int length = method_ordering->length();
3170 if (JvmtiExport::can_maintain_original_method_order() ||
3171 (UseSharedSpaces && length != 0)) {
3172 guarantee(length == methods()->length(), "invalid method ordering length");
3173 jlong sum = 0;
3174 for (int j = 0; j < length; j++) {
3175 int original_index = method_ordering->at(j);
3176 guarantee(original_index >= 0, "invalid method ordering index");
3177 guarantee(original_index < length, "invalid method ordering index");
3178 sum += original_index;
3179 }
3180 // Verify sum of indices 0,1,...,length-1
3181 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3182 } else {
3183 guarantee(length == 0, "invalid method ordering length");
3184 }
3185 }
3186
3187 // Verify JNI static field identifiers
3188 if (jni_ids() != NULL) {
3189 jni_ids()->verify(this);
3190 }
3191
3192 // Verify other fields
3193 if (array_klasses() != NULL) {
3194 guarantee(array_klasses()->is_metadata(), "should be in metaspace");
3195 guarantee(array_klasses()->is_klass(), "should be klass");
3196 }
3197 if (constants() != NULL) {
3198 guarantee(constants()->is_metadata(), "should be in metaspace");
3199 guarantee(constants()->is_constantPool(), "should be constant pool");
3200 }
3201 if (protection_domain() != NULL) {
3202 guarantee(protection_domain()->is_oop(), "should be oop");
3203 }
3204 const Klass* host = host_klass();
3205 if (host != NULL) {
3206 guarantee(host->is_metadata(), "should be in metaspace");
3207 guarantee(host->is_klass(), "should be klass");
3208 }
3209 if (signers() != NULL) {
3210 guarantee(signers()->is_objArray(), "should be obj array");
3211 }
3212 }
3213
3214 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3215 Klass::oop_verify_on(obj, st);
3216 VerifyFieldClosure blk;
3217 obj->oop_iterate_no_header(&blk);
3218 }
3219
3220
3221 // JNIid class for jfieldIDs only
3222 // Note to reviewers:
3223 // These JNI functions are just moved over to column 1 and not changed
3224 // in the compressed oops workspace.
3225 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3226 _holder = holder;
3227 _offset = offset;
3228 _next = next;
3229 debug_only(_is_static_field_id = false;)
3230 }
3231
3232
3233 JNIid* JNIid::find(int offset) {
3234 JNIid* current = this;
3235 while (current != NULL) {
3236 if (current->offset() == offset) return current;
3237 current = current->next();
3238 }
3239 return NULL;
3240 }
3241
3242 void JNIid::deallocate(JNIid* current) {
3243 while (current != NULL) {
3244 JNIid* next = current->next();
3245 delete current;
3246 current = next;
3247 }
3248 }
3249
3250
3251 void JNIid::verify(Klass* holder) {
3252 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3253 int end_field_offset;
3254 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3255
3256 JNIid* current = this;
3257 while (current != NULL) {
3258 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3259 #ifdef ASSERT
3260 int o = current->offset();
3261 if (current->is_static_field_id()) {
3262 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3263 }
3264 #endif
3265 current = current->next();
3266 }
3267 }
3268
3269
3270 #ifdef ASSERT
3271 void InstanceKlass::set_init_state(ClassState state) {
3272 bool good_state = is_shared() ? (_init_state <= state)
3273 : (_init_state < state);
3274 assert(good_state || state == allocated, "illegal state transition");
3275 _init_state = (u1)state;
3276 }
3277 #endif
3278
3279
3280 // RedefineClasses() support for previous versions:
3281
3282 // Purge previous versions
3283 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3284 if (ik->previous_versions() != NULL) {
3285 // This klass has previous versions so see what we can cleanup
3286 // while it is safe to do so.
3287
3288 int deleted_count = 0; // leave debugging breadcrumbs
3289 int live_count = 0;
3290 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3291 ClassLoaderData::the_null_class_loader_data() :
3292 ik->class_loader_data();
3293
3294 // RC_TRACE macro has an embedded ResourceMark
3295 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3296 ik->external_name(), ik->previous_versions()->length()));
3297
3298 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3299 // check the previous versions array
3300 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3301 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3302 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3303
3304 ConstantPool* pvcp = cp_ref;
3305 if (!pvcp->on_stack()) {
3306 // If the constant pool isn't on stack, none of the methods
3307 // are executing. Delete all the methods, the constant pool and
3308 // and this previous version node.
3309 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3310 if (method_refs != NULL) {
3311 for (int j = method_refs->length() - 1; j >= 0; j--) {
3312 Method* method = method_refs->at(j);
3313 assert(method != NULL, "method ref was unexpectedly cleared");
3314 method_refs->remove_at(j);
3315 // method will be freed with associated class.
3316 }
3317 }
3318 // Remove the constant pool
3319 delete pv_node;
3320 // Since we are traversing the array backwards, we don't have to
3321 // do anything special with the index.
3322 ik->previous_versions()->remove_at(i);
3323 deleted_count++;
3324 continue;
3325 } else {
3326 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3327 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3328 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3329 live_count++;
3330 }
3331
3332 // At least one method is live in this previous version, clean out
3333 // the others or mark them as obsolete.
3334 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3335 if (method_refs != NULL) {
3336 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3337 method_refs->length()));
3338 for (int j = method_refs->length() - 1; j >= 0; j--) {
3339 Method* method = method_refs->at(j);
3340 assert(method != NULL, "method ref was unexpectedly cleared");
3341
3342 // Remove the emcp method if it's not executing
3343 // If it's been made obsolete by a redefinition of a non-emcp
3344 // method, mark it as obsolete but leave it to clean up later.
3345 if (!method->on_stack()) {
3346 method_refs->remove_at(j);
3347 } else if (emcp_method_count == 0) {
3348 method->set_is_obsolete();
3349 } else {
3350 // RC_TRACE macro has an embedded ResourceMark
3351 RC_TRACE(0x00000200,
3352 ("purge: %s(%s): prev method @%d in version @%d is alive",
3353 method->name()->as_C_string(),
3354 method->signature()->as_C_string(), j, i));
3355 }
3356 }
3357 }
3358 }
3359 assert(ik->previous_versions()->length() == live_count, "sanity check");
3360 RC_TRACE(0x00000200,
3361 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3362 deleted_count));
3363 }
3364 }
3365
3366 // External interface for use during class unloading.
3367 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3368 // Call with >0 emcp methods since they are not currently being redefined.
3369 purge_previous_versions_internal(ik, 1);
3370 }
3371
3372
3373 // Potentially add an information node that contains pointers to the
3374 // interesting parts of the previous version of the_class.
3375 // This is also where we clean out any unused references.
3376 // Note that while we delete nodes from the _previous_versions
3377 // array, we never delete the array itself until the klass is
3378 // unloaded. The has_been_redefined() query depends on that fact.
3379 //
3380 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3381 BitMap* emcp_methods, int emcp_method_count) {
3382 assert(Thread::current()->is_VM_thread(),
3383 "only VMThread can add previous versions");
3384
3385 if (_previous_versions == NULL) {
3386 // This is the first previous version so make some space.
3387 // Start with 2 elements under the assumption that the class
3388 // won't be redefined much.
3389 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3390 GrowableArray<PreviousVersionNode *>(2, true);
3391 }
3392
3393 ConstantPool* cp_ref = ikh->constants();
3394
3395 // RC_TRACE macro has an embedded ResourceMark
3396 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3397 "on_stack=%d",
3398 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3399 cp_ref->on_stack()));
3400
3401 // If the constant pool for this previous version of the class
3402 // is not marked as being on the stack, then none of the methods
3403 // in this previous version of the class are on the stack so
3404 // we don't need to create a new PreviousVersionNode. However,
3405 // we still need to examine older previous versions below.
3406 Array<Method*>* old_methods = ikh->methods();
3407
3408 if (cp_ref->on_stack()) {
3409 PreviousVersionNode * pv_node = NULL;
3410 if (emcp_method_count == 0) {
3411 // non-shared ConstantPool gets a reference
3412 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), NULL);
3413 RC_TRACE(0x00000400,
3414 ("add: all methods are obsolete; flushing any EMCP refs"));
3415 } else {
3416 int local_count = 0;
3417 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3418 GrowableArray<Method*>(emcp_method_count, true);
3419 for (int i = 0; i < old_methods->length(); i++) {
3420 if (emcp_methods->at(i)) {
3421 // this old method is EMCP. Save it only if it's on the stack
3422 Method* old_method = old_methods->at(i);
3423 if (old_method->on_stack()) {
3424 method_refs->append(old_method);
3425 }
3426 if (++local_count >= emcp_method_count) {
3427 // no more EMCP methods so bail out now
3428 break;
3429 }
3430 }
3431 }
3432 // non-shared ConstantPool gets a reference
3433 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), method_refs);
3434 }
3435 // append new previous version.
3436 _previous_versions->append(pv_node);
3437 }
3438
3439 // Since the caller is the VMThread and we are at a safepoint, this
3440 // is a good time to clear out unused references.
3441
3442 RC_TRACE(0x00000400, ("add: previous version length=%d",
3443 _previous_versions->length()));
3444
3445 // Purge previous versions not executing on the stack
3446 purge_previous_versions_internal(this, emcp_method_count);
3447
3448 int obsolete_method_count = old_methods->length() - emcp_method_count;
3449
3450 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3451 _previous_versions->length() > 0) {
3452 // We have a mix of obsolete and EMCP methods so we have to
3453 // clear out any matching EMCP method entries the hard way.
3454 int local_count = 0;
3455 for (int i = 0; i < old_methods->length(); i++) {
3456 if (!emcp_methods->at(i)) {
3457 // only obsolete methods are interesting
3458 Method* old_method = old_methods->at(i);
3459 Symbol* m_name = old_method->name();
3460 Symbol* m_signature = old_method->signature();
3461
3462 // we might not have added the last entry
3463 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3464 // check the previous versions array for non executing obsolete methods
3465 PreviousVersionNode * pv_node = _previous_versions->at(j);
3466
3467 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3468 if (method_refs == NULL) {
3469 // We have run into a PreviousVersion generation where
3470 // all methods were made obsolete during that generation's
3471 // RedefineClasses() operation. At the time of that
3472 // operation, all EMCP methods were flushed so we don't
3473 // have to go back any further.
3474 //
3475 // A NULL method_refs is different than an empty method_refs.
3476 // We cannot infer any optimizations about older generations
3477 // from an empty method_refs for the current generation.
3478 break;
3479 }
3480
3481 for (int k = method_refs->length() - 1; k >= 0; k--) {
3482 Method* method = method_refs->at(k);
3483
3484 if (!method->is_obsolete() &&
3485 method->name() == m_name &&
3486 method->signature() == m_signature) {
3487 // The current RedefineClasses() call has made all EMCP
3488 // versions of this method obsolete so mark it as obsolete
3489 // and remove the reference.
3490 RC_TRACE(0x00000400,
3491 ("add: %s(%s): flush obsolete method @%d in version @%d",
3492 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3493
3494 method->set_is_obsolete();
3495 // Leave obsolete methods on the previous version list to
3496 // clean up later.
3497 break;
3498 }
3499 }
3500
3501 // The previous loop may not find a matching EMCP method, but
3502 // that doesn't mean that we can optimize and not go any
3503 // further back in the PreviousVersion generations. The EMCP
3504 // method for this generation could have already been deleted,
3505 // but there still may be an older EMCP method that has not
3506 // been deleted.
3507 }
3508
3509 if (++local_count >= obsolete_method_count) {
3510 // no more obsolete methods so bail out now
3511 break;
3512 }
3513 }
3514 }
3515 }
3516 } // end add_previous_version()
3517
3518
3519 // Determine if InstanceKlass has a previous version.
3520 bool InstanceKlass::has_previous_version() const {
3521 return (_previous_versions != NULL && _previous_versions->length() > 0);
3522 } // end has_previous_version()
3523
3524
3525 Method* InstanceKlass::method_with_idnum(int idnum) {
3526 Method* m = NULL;
3527 if (idnum < methods()->length()) {
3528 m = methods()->at(idnum);
3529 }
3530 if (m == NULL || m->method_idnum() != idnum) {
3531 for (int index = 0; index < methods()->length(); ++index) {
3532 m = methods()->at(index);
3533 if (m->method_idnum() == idnum) {
3534 return m;
3535 }
3536 }
3537 }
3538 return m;
3539 }
3540
3541
3542 // Construct a PreviousVersionNode entry for the array hung off
3543 // the InstanceKlass.
3544 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3545 bool prev_cp_is_weak, GrowableArray<Method*>* prev_EMCP_methods) {
3546
3547 _prev_constant_pool = prev_constant_pool;
3548 _prev_cp_is_weak = prev_cp_is_weak;
3549 _prev_EMCP_methods = prev_EMCP_methods;
3550 }
3551
3552
3553 // Destroy a PreviousVersionNode
3554 PreviousVersionNode::~PreviousVersionNode() {
3555 if (_prev_constant_pool != NULL) {
3556 _prev_constant_pool = NULL;
3557 }
3558
3559 if (_prev_EMCP_methods != NULL) {
3560 delete _prev_EMCP_methods;
3561 }
3562 }
3563
3564
3565 // Construct a PreviousVersionInfo entry
3566 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
3567 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
3568 _prev_EMCP_method_handles = NULL;
3569
3570 ConstantPool* cp = pv_node->prev_constant_pool();
3571 assert(cp != NULL, "constant pool ref was unexpectedly cleared");
3572 if (cp == NULL) {
3573 return; // robustness
3574 }
3575
3576 // make the ConstantPool* safe to return
3577 _prev_constant_pool_handle = constantPoolHandle(cp);
3578
3579 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3580 if (method_refs == NULL) {
3581 // the InstanceKlass did not have any EMCP methods
3582 return;
3583 }
3584
3585 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
3586
3587 int n_methods = method_refs->length();
3588 for (int i = 0; i < n_methods; i++) {
3589 Method* method = method_refs->at(i);
3590 assert (method != NULL, "method has been cleared");
3591 if (method == NULL) {
3592 continue; // robustness
3593 }
3594 // make the Method* safe to return
3595 _prev_EMCP_method_handles->append(methodHandle(method));
3596 }
3597 }
3598
3599
3600 // Destroy a PreviousVersionInfo
3601 PreviousVersionInfo::~PreviousVersionInfo() {
3602 // Since _prev_EMCP_method_handles is not C-heap allocated, we
3603 // don't have to delete it.
3604 }
3605
3606
3607 // Construct a helper for walking the previous versions array
3608 PreviousVersionWalker::PreviousVersionWalker(InstanceKlass *ik) {
3609 _previous_versions = ik->previous_versions();
3610 _current_index = 0;
3611 // _hm needs no initialization
3612 _current_p = NULL;
3613 }
3614
3615
3616 // Destroy a PreviousVersionWalker
3617 PreviousVersionWalker::~PreviousVersionWalker() {
3618 // Delete the current info just in case the caller didn't walk to
3619 // the end of the previous versions list. No harm if _current_p is
3620 // already NULL.
3621 delete _current_p;
3622
3623 // When _hm is destroyed, all the Handles returned in
3624 // PreviousVersionInfo objects will be destroyed.
3625 // Also, after this destructor is finished it will be
3626 // safe to delete the GrowableArray allocated in the
3627 // PreviousVersionInfo objects.
3628 }
3629
3630
3631 // Return the interesting information for the next previous version
3632 // of the klass. Returns NULL if there are no more previous versions.
3633 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
3634 if (_previous_versions == NULL) {
3635 // no previous versions so nothing to return
3636 return NULL;
3637 }
3638
3639 delete _current_p; // cleanup the previous info for the caller
3640 _current_p = NULL; // reset to NULL so we don't delete same object twice
3641
3642 int length = _previous_versions->length();
3643
3644 while (_current_index < length) {
3645 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3646 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP, mtClass)
3647 PreviousVersionInfo(pv_node);
3648
3649 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
3650 assert (!cp_h.is_null(), "null cp found in previous version");
3651
3652 // The caller will need to delete pv_info when they are done with it.
3653 _current_p = pv_info;
3654 return pv_info;
3655 }
3656
3657 // all of the underlying nodes' info has been deleted
3658 return NULL;
3659 } // end next_previous_version()