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