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