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