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