1 /*
2 * Copyright (c) 1997, 2017, 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 "aot/aotLoader.hpp"
27 #include "classfile/classFileParser.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/javaClasses.hpp"
31 #include "classfile/moduleEntry.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/systemDictionaryShared.hpp"
34 #include "classfile/verifier.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "code/dependencyContext.hpp"
37 #include "compiler/compileBroker.hpp"
38 #include "gc/shared/collectedHeap.inline.hpp"
39 #include "gc/shared/specialized_oop_closures.hpp"
40 #include "interpreter/oopMapCache.hpp"
41 #include "interpreter/rewriter.hpp"
42 #include "jvmtifiles/jvmti.h"
43 #include "logging/log.hpp"
44 #include "logging/logMessage.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/heapInspection.hpp"
47 #include "memory/iterator.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.hpp"
50 #include "memory/metaspaceShared.hpp"
51 #include "memory/oopFactory.hpp"
52 #include "memory/resourceArea.hpp"
53 #include "oops/fieldStreams.hpp"
54 #include "oops/instanceClassLoaderKlass.hpp"
55 #include "oops/instanceKlass.inline.hpp"
56 #include "oops/instanceMirrorKlass.hpp"
57 #include "oops/instanceOop.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/method.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/symbol.hpp"
62 #include "prims/jvm.h"
63 #include "prims/jvmtiExport.hpp"
64 #include "prims/jvmtiRedefineClasses.hpp"
65 #include "prims/jvmtiThreadState.hpp"
66 #include "prims/methodComparator.hpp"
67 #include "runtime/atomic.hpp"
68 #include "runtime/fieldDescriptor.hpp"
69 #include "runtime/handles.inline.hpp"
70 #include "runtime/javaCalls.hpp"
71 #include "runtime/mutexLocker.hpp"
72 #include "runtime/orderAccess.inline.hpp"
73 #include "runtime/thread.inline.hpp"
74 #include "services/classLoadingService.hpp"
75 #include "services/threadService.hpp"
76 #include "utilities/dtrace.hpp"
77 #include "utilities/macros.hpp"
78 #include "utilities/stringUtils.hpp"
79 #ifdef COMPILER1
80 #include "c1/c1_Compiler.hpp"
81 #endif
82
83 #ifdef DTRACE_ENABLED
84
85
86 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
87 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
88 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
89 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
90 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
91 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
92 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
93 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
94 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
95 { \
96 char* data = NULL; \
97 int len = 0; \
98 Symbol* clss_name = name(); \
99 if (clss_name != NULL) { \
100 data = (char*)clss_name->bytes(); \
101 len = clss_name->utf8_length(); \
102 } \
103 HOTSPOT_CLASS_INITIALIZATION_##type( \
104 data, len, (void*)class_loader(), thread_type); \
105 }
106
107 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
108 { \
109 char* data = NULL; \
110 int len = 0; \
111 Symbol* clss_name = name(); \
112 if (clss_name != NULL) { \
113 data = (char*)clss_name->bytes(); \
114 len = clss_name->utf8_length(); \
115 } \
116 HOTSPOT_CLASS_INITIALIZATION_##type( \
117 data, len, (void*)class_loader(), thread_type, wait); \
118 }
119
120 #else // ndef DTRACE_ENABLED
121
122 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
123 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
124
125 #endif // ndef DTRACE_ENABLED
126
127 volatile int InstanceKlass::_total_instanceKlass_count = 0;
128
129 static inline bool is_class_loader(const Symbol* class_name,
130 const ClassFileParser& parser) {
131 assert(class_name != NULL, "invariant");
132
133 if (class_name == vmSymbols::java_lang_ClassLoader()) {
134 return true;
135 }
136
137 if (SystemDictionary::ClassLoader_klass_loaded()) {
138 const Klass* const super_klass = parser.super_klass();
139 if (super_klass != NULL) {
140 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
141 return true;
142 }
143 }
144 }
145 return false;
146 }
147
148 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
149 const int size = InstanceKlass::size(parser.vtable_size(),
150 parser.itable_size(),
151 nonstatic_oop_map_size(parser.total_oop_map_count()),
152 parser.is_interface(),
153 parser.is_anonymous(),
154 should_store_fingerprint());
155
156 const Symbol* const class_name = parser.class_name();
157 assert(class_name != NULL, "invariant");
158 ClassLoaderData* loader_data = parser.loader_data();
159 assert(loader_data != NULL, "invariant");
160
161 InstanceKlass* ik;
162
163 // Allocation
164 if (REF_NONE == parser.reference_type()) {
165 if (class_name == vmSymbols::java_lang_Class()) {
166 // mirror
167 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
168 }
169 else if (is_class_loader(class_name, parser)) {
170 // class loader
171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
172 }
173 else {
174 // normal
175 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
176 }
177 }
178 else {
179 // reference
180 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
181 }
182
183 // Check for pending exception before adding to the loader data and incrementing
184 // class count. Can get OOM here.
185 if (HAS_PENDING_EXCEPTION) {
186 return NULL;
187 }
188
189 assert(ik != NULL, "invariant");
190
191 const bool publicize = !parser.is_internal();
192
193 // Add all classes to our internal class loader list here,
194 // including classes in the bootstrap (NULL) class loader.
195 loader_data->add_class(ik, publicize);
196 Atomic::inc(&_total_instanceKlass_count);
197
198 return ik;
199 }
200
201
202 // copy method ordering from resource area to Metaspace
203 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
204 if (m != NULL) {
205 // allocate a new array and copy contents (memcpy?)
206 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
207 for (int i = 0; i < m->length(); i++) {
208 _method_ordering->at_put(i, m->at(i));
209 }
210 } else {
211 _method_ordering = Universe::the_empty_int_array();
212 }
213 }
214
215 // create a new array of vtable_indices for default methods
216 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
217 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
218 assert(default_vtable_indices() == NULL, "only create once");
219 set_default_vtable_indices(vtable_indices);
220 return vtable_indices;
221 }
222
223 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
224 _static_field_size(parser.static_field_size()),
225 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
226 _itable_len(parser.itable_size()),
227 _reference_type(parser.reference_type()) {
228 set_vtable_length(parser.vtable_size());
229 set_kind(kind);
230 set_access_flags(parser.access_flags());
231 set_is_anonymous(parser.is_anonymous());
232 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
233 false));
234
235 assert(NULL == _methods, "underlying memory not zeroed?");
236 assert(is_instance_klass(), "is layout incorrect?");
237 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
238 }
239
240 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
241 Array<Method*>* methods) {
242 if (methods != NULL && methods != Universe::the_empty_method_array() &&
243 !methods->is_shared()) {
244 for (int i = 0; i < methods->length(); i++) {
245 Method* method = methods->at(i);
246 if (method == NULL) continue; // maybe null if error processing
247 // Only want to delete methods that are not executing for RedefineClasses.
248 // The previous version will point to them so they're not totally dangling
249 assert (!method->on_stack(), "shouldn't be called with methods on stack");
250 MetadataFactory::free_metadata(loader_data, method);
251 }
252 MetadataFactory::free_array<Method*>(loader_data, methods);
253 }
254 }
255
256 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
257 const Klass* super_klass,
258 Array<Klass*>* local_interfaces,
259 Array<Klass*>* transitive_interfaces) {
260 // Only deallocate transitive interfaces if not empty, same as super class
261 // or same as local interfaces. See code in parseClassFile.
262 Array<Klass*>* ti = transitive_interfaces;
263 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
264 // check that the interfaces don't come from super class
265 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
266 InstanceKlass::cast(super_klass)->transitive_interfaces();
267 if (ti != sti && ti != NULL && !ti->is_shared()) {
268 MetadataFactory::free_array<Klass*>(loader_data, ti);
269 }
270 }
271
272 // local interfaces can be empty
273 if (local_interfaces != Universe::the_empty_klass_array() &&
274 local_interfaces != NULL && !local_interfaces->is_shared()) {
275 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
276 }
277 }
278
279 // This function deallocates the metadata and C heap pointers that the
280 // InstanceKlass points to.
281 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
282
283 // Orphan the mirror first, CMS thinks it's still live.
284 if (java_mirror() != NULL) {
285 java_lang_Class::set_klass(java_mirror(), NULL);
286 }
287
288 // Need to take this class off the class loader data list.
289 loader_data->remove_class(this);
290
291 // The array_klass for this class is created later, after error handling.
292 // For class redefinition, we keep the original class so this scratch class
293 // doesn't have an array class. Either way, assert that there is nothing
294 // to deallocate.
295 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
296
297 // Release C heap allocated data that this might point to, which includes
298 // reference counting symbol names.
299 release_C_heap_structures();
300
301 deallocate_methods(loader_data, methods());
302 set_methods(NULL);
303
304 if (method_ordering() != NULL &&
305 method_ordering() != Universe::the_empty_int_array() &&
306 !method_ordering()->is_shared()) {
307 MetadataFactory::free_array<int>(loader_data, method_ordering());
308 }
309 set_method_ordering(NULL);
310
311 // default methods can be empty
312 if (default_methods() != NULL &&
313 default_methods() != Universe::the_empty_method_array() &&
314 !default_methods()->is_shared()) {
315 MetadataFactory::free_array<Method*>(loader_data, default_methods());
316 }
317 // Do NOT deallocate the default methods, they are owned by superinterfaces.
318 set_default_methods(NULL);
319
320 // default methods vtable indices can be empty
321 if (default_vtable_indices() != NULL &&
322 !default_vtable_indices()->is_shared()) {
323 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
324 }
325 set_default_vtable_indices(NULL);
326
327
328 // This array is in Klass, but remove it with the InstanceKlass since
329 // this place would be the only caller and it can share memory with transitive
330 // interfaces.
331 if (secondary_supers() != NULL &&
332 secondary_supers() != Universe::the_empty_klass_array() &&
333 secondary_supers() != transitive_interfaces() &&
334 !secondary_supers()->is_shared()) {
335 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
336 }
337 set_secondary_supers(NULL);
338
339 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
340 set_transitive_interfaces(NULL);
341 set_local_interfaces(NULL);
342
343 if (fields() != NULL && !fields()->is_shared()) {
344 MetadataFactory::free_array<jushort>(loader_data, fields());
345 }
346 set_fields(NULL, 0);
347
348 // If a method from a redefined class is using this constant pool, don't
349 // delete it, yet. The new class's previous version will point to this.
350 if (constants() != NULL) {
351 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
352 if (!constants()->is_shared()) {
353 MetadataFactory::free_metadata(loader_data, constants());
354 }
355 // Delete any cached resolution errors for the constant pool
356 SystemDictionary::delete_resolution_error(constants());
357
358 set_constants(NULL);
359 }
360
361 if (inner_classes() != NULL &&
362 inner_classes() != Universe::the_empty_short_array() &&
363 !inner_classes()->is_shared()) {
364 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
365 }
366 set_inner_classes(NULL);
367
368 // We should deallocate the Annotations instance if it's not in shared spaces.
369 if (annotations() != NULL && !annotations()->is_shared()) {
370 MetadataFactory::free_metadata(loader_data, annotations());
371 }
372 set_annotations(NULL);
373 }
374
375 bool InstanceKlass::should_be_initialized() const {
376 return !is_initialized();
377 }
378
379 klassItable InstanceKlass::itable() const {
380 return klassItable(const_cast<InstanceKlass*>(this));
381 }
382
383 void InstanceKlass::eager_initialize(Thread *thread) {
384 if (!EagerInitialization) return;
385
386 if (this->is_not_initialized()) {
387 // abort if the the class has a class initializer
388 if (this->class_initializer() != NULL) return;
389
390 // abort if it is java.lang.Object (initialization is handled in genesis)
391 Klass* super_klass = super();
392 if (super_klass == NULL) return;
393
394 // abort if the super class should be initialized
395 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
396
397 // call body to expose the this pointer
398 eager_initialize_impl();
399 }
400 }
401
402 // JVMTI spec thinks there are signers and protection domain in the
403 // instanceKlass. These accessors pretend these fields are there.
404 // The hprof specification also thinks these fields are in InstanceKlass.
405 oop InstanceKlass::protection_domain() const {
406 // return the protection_domain from the mirror
407 return java_lang_Class::protection_domain(java_mirror());
408 }
409
410 // To remove these from requires an incompatible change and CCC request.
411 objArrayOop InstanceKlass::signers() const {
412 // return the signers from the mirror
413 return java_lang_Class::signers(java_mirror());
414 }
415
416 oop InstanceKlass::init_lock() const {
417 // return the init lock from the mirror
418 oop lock = java_lang_Class::init_lock(java_mirror());
419 // Prevent reordering with any access of initialization state
420 OrderAccess::loadload();
421 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
422 "only fully initialized state can have a null lock");
423 return lock;
424 }
425
426 // Set the initialization lock to null so the object can be GC'ed. Any racing
427 // threads to get this lock will see a null lock and will not lock.
428 // That's okay because they all check for initialized state after getting
429 // the lock and return.
430 void InstanceKlass::fence_and_clear_init_lock() {
431 // make sure previous stores are all done, notably the init_state.
432 OrderAccess::storestore();
433 java_lang_Class::set_init_lock(java_mirror(), NULL);
434 assert(!is_not_initialized(), "class must be initialized now");
435 }
436
437 void InstanceKlass::eager_initialize_impl() {
438 EXCEPTION_MARK;
439 HandleMark hm(THREAD);
440 Handle h_init_lock(THREAD, init_lock());
441 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
442
443 // abort if someone beat us to the initialization
444 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
445
446 ClassState old_state = init_state();
447 link_class_impl(true, THREAD);
448 if (HAS_PENDING_EXCEPTION) {
449 CLEAR_PENDING_EXCEPTION;
450 // Abort if linking the class throws an exception.
451
452 // Use a test to avoid redundantly resetting the state if there's
453 // no change. Set_init_state() asserts that state changes make
454 // progress, whereas here we might just be spinning in place.
455 if (old_state != _init_state)
456 set_init_state(old_state);
457 } else {
458 // linking successfull, mark class as initialized
459 set_init_state(fully_initialized);
460 fence_and_clear_init_lock();
461 // trace
462 if (log_is_enabled(Info, class, init)) {
463 ResourceMark rm(THREAD);
464 log_info(class, init)("[Initialized %s without side effects]", external_name());
465 }
466 }
467 }
468
469
470 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
471 // process. The step comments refers to the procedure described in that section.
472 // Note: implementation moved to static method to expose the this pointer.
473 void InstanceKlass::initialize(TRAPS) {
474 if (this->should_be_initialized()) {
475 initialize_impl(CHECK);
476 // Note: at this point the class may be initialized
477 // OR it may be in the state of being initialized
478 // in case of recursive initialization!
479 } else {
480 assert(is_initialized(), "sanity check");
481 }
482 }
483
484
485 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
486 // 1) Verify the bytecodes
487 Verifier::Mode mode =
488 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
489 return Verifier::verify(this, mode, should_verify_class(), THREAD);
490 }
491
492
493 // Used exclusively by the shared spaces dump mechanism to prevent
494 // classes mapped into the shared regions in new VMs from appearing linked.
495
496 void InstanceKlass::unlink_class() {
497 assert(is_linked(), "must be linked");
498 _init_state = loaded;
499 }
500
501 void InstanceKlass::link_class(TRAPS) {
502 assert(is_loaded(), "must be loaded");
503 if (!is_linked()) {
504 link_class_impl(true, CHECK);
505 }
506 }
507
508 // Called to verify that a class can link during initialization, without
509 // throwing a VerifyError.
510 bool InstanceKlass::link_class_or_fail(TRAPS) {
511 assert(is_loaded(), "must be loaded");
512 if (!is_linked()) {
513 link_class_impl(false, CHECK_false);
514 }
515 return is_linked();
516 }
517
518 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
519 if (DumpSharedSpaces && is_in_error_state()) {
520 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
521 // the class has failed verification. Throwing the NoClassDefFoundError here is just
522 // a convenient way to stop repeat attempts to verify the same (bad) class.
523 //
524 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
525 // if we are executing Java code. This is not a problem for CDS dumping phase since
526 // it doesn't execute any Java code.
527 ResourceMark rm(THREAD);
528 Exceptions::fthrow(THREAD_AND_LOCATION,
529 vmSymbols::java_lang_NoClassDefFoundError(),
530 "Class %s, or one of its supertypes, failed class initialization",
531 external_name());
532 return false;
533 }
534 // return if already verified
535 if (is_linked()) {
536 return true;
537 }
538
539 // Timing
540 // timer handles recursion
541 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
542 JavaThread* jt = (JavaThread*)THREAD;
543
544 // link super class before linking this class
545 Klass* super_klass = super();
546 if (super_klass != NULL) {
547 if (super_klass->is_interface()) { // check if super class is an interface
548 ResourceMark rm(THREAD);
549 Exceptions::fthrow(
550 THREAD_AND_LOCATION,
551 vmSymbols::java_lang_IncompatibleClassChangeError(),
552 "class %s has interface %s as super class",
553 external_name(),
554 super_klass->external_name()
555 );
556 return false;
557 }
558
559 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
560 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
561 }
562
563 // link all interfaces implemented by this class before linking this class
564 Array<Klass*>* interfaces = local_interfaces();
565 int num_interfaces = interfaces->length();
566 for (int index = 0; index < num_interfaces; index++) {
567 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
568 interk->link_class_impl(throw_verifyerror, CHECK_false);
569 }
570
571 // in case the class is linked in the process of linking its superclasses
572 if (is_linked()) {
573 return true;
574 }
575
576 // trace only the link time for this klass that includes
577 // the verification time
578 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
579 ClassLoader::perf_class_link_selftime(),
580 ClassLoader::perf_classes_linked(),
581 jt->get_thread_stat()->perf_recursion_counts_addr(),
582 jt->get_thread_stat()->perf_timers_addr(),
583 PerfClassTraceTime::CLASS_LINK);
584
585 // verification & rewriting
586 {
587 HandleMark hm(THREAD);
588 Handle h_init_lock(THREAD, init_lock());
589 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
590 // rewritten will have been set if loader constraint error found
591 // on an earlier link attempt
592 // don't verify or rewrite if already rewritten
593 //
594
595 if (!is_linked()) {
596 if (!is_rewritten()) {
597 {
598 bool verify_ok = verify_code(throw_verifyerror, THREAD);
599 if (!verify_ok) {
600 return false;
601 }
602 }
603
604 // Just in case a side-effect of verify linked this class already
605 // (which can sometimes happen since the verifier loads classes
606 // using custom class loaders, which are free to initialize things)
607 if (is_linked()) {
608 return true;
609 }
610
611 // also sets rewritten
612 rewrite_class(CHECK_false);
613 } else if (is_shared()) {
614 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
615 }
616
617 // relocate jsrs and link methods after they are all rewritten
618 link_methods(CHECK_false);
619
620 // Initialize the vtable and interface table after
621 // methods have been rewritten since rewrite may
622 // fabricate new Method*s.
623 // also does loader constraint checking
624 //
625 // initialize_vtable and initialize_itable need to be rerun for
626 // a shared class if the class is not loaded by the NULL classloader.
627 ClassLoaderData * loader_data = class_loader_data();
628 if (!(is_shared() &&
629 loader_data->is_the_null_class_loader_data())) {
630 ResourceMark rm(THREAD);
631 vtable().initialize_vtable(true, CHECK_false);
632 itable().initialize_itable(true, CHECK_false);
633 }
634 #ifdef ASSERT
635 else {
636 vtable().verify(tty, true);
637 // In case itable verification is ever added.
638 // itable().verify(tty, true);
639 }
640 #endif
641 set_init_state(linked);
642 if (JvmtiExport::should_post_class_prepare()) {
643 Thread *thread = THREAD;
644 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
645 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
646 }
647 }
648 }
649 return true;
650 }
651
652
653 // Rewrite the byte codes of all of the methods of a class.
654 // The rewriter must be called exactly once. Rewriting must happen after
655 // verification but before the first method of the class is executed.
656 void InstanceKlass::rewrite_class(TRAPS) {
657 assert(is_loaded(), "must be loaded");
658 if (is_rewritten()) {
659 assert(is_shared(), "rewriting an unshared class?");
660 return;
661 }
662 Rewriter::rewrite(this, CHECK);
663 set_rewritten();
664 }
665
666 // Now relocate and link method entry points after class is rewritten.
667 // This is outside is_rewritten flag. In case of an exception, it can be
668 // executed more than once.
669 void InstanceKlass::link_methods(TRAPS) {
670 int len = methods()->length();
671 for (int i = len-1; i >= 0; i--) {
672 methodHandle m(THREAD, methods()->at(i));
673
674 // Set up method entry points for compiler and interpreter .
675 m->link_method(m, CHECK);
676 }
677 }
678
679 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
680 void InstanceKlass::initialize_super_interfaces(TRAPS) {
681 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
682 for (int i = 0; i < local_interfaces()->length(); ++i) {
683 Klass* iface = local_interfaces()->at(i);
684 InstanceKlass* ik = InstanceKlass::cast(iface);
685
686 // Initialization is depth first search ie. we start with top of the inheritance tree
687 // has_nonstatic_concrete_methods drives searching superinterfaces since it
688 // means has_nonstatic_concrete_methods in its superinterface hierarchy
689 if (ik->has_nonstatic_concrete_methods()) {
690 ik->initialize_super_interfaces(CHECK);
691 }
692
693 // Only initialize() interfaces that "declare" concrete methods.
694 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
695 ik->initialize(CHECK);
696 }
697 }
698 }
699
700 void InstanceKlass::initialize_impl(TRAPS) {
701 HandleMark hm(THREAD);
702
703 // Make sure klass is linked (verified) before initialization
704 // A class could already be verified, since it has been reflected upon.
705 link_class(CHECK);
706
707 DTRACE_CLASSINIT_PROBE(required, -1);
708
709 bool wait = false;
710
711 // refer to the JVM book page 47 for description of steps
712 // Step 1
713 {
714 Handle h_init_lock(THREAD, init_lock());
715 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
716
717 Thread *self = THREAD; // it's passed the current thread
718
719 // Step 2
720 // If we were to use wait() instead of waitInterruptibly() then
721 // we might end up throwing IE from link/symbol resolution sites
722 // that aren't expected to throw. This would wreak havoc. See 6320309.
723 while(is_being_initialized() && !is_reentrant_initialization(self)) {
724 wait = true;
725 ol.waitUninterruptibly(CHECK);
726 }
727
728 // Step 3
729 if (is_being_initialized() && is_reentrant_initialization(self)) {
730 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
731 return;
732 }
733
734 // Step 4
735 if (is_initialized()) {
736 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
737 return;
738 }
739
740 // Step 5
741 if (is_in_error_state()) {
742 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
743 ResourceMark rm(THREAD);
744 const char* desc = "Could not initialize class ";
745 const char* className = external_name();
746 size_t msglen = strlen(desc) + strlen(className) + 1;
747 char* message = NEW_RESOURCE_ARRAY(char, msglen);
748 if (NULL == message) {
749 // Out of memory: can't create detailed error message
750 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
751 } else {
752 jio_snprintf(message, msglen, "%s%s", desc, className);
753 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
754 }
755 }
756
757 // Step 6
758 set_init_state(being_initialized);
759 set_init_thread(self);
760 }
761
762 // Step 7
763 // Next, if C is a class rather than an interface, initialize it's super class and super
764 // interfaces.
765 if (!is_interface()) {
766 Klass* super_klass = super();
767 if (super_klass != NULL && super_klass->should_be_initialized()) {
768 super_klass->initialize(THREAD);
769 }
770 // If C implements any interface that declares a non-static, concrete method,
771 // the initialization of C triggers initialization of its super interfaces.
772 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
773 // having a superinterface that declares, non-static, concrete methods
774 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
775 initialize_super_interfaces(THREAD);
776 }
777
778 // If any exceptions, complete abruptly, throwing the same exception as above.
779 if (HAS_PENDING_EXCEPTION) {
780 Handle e(THREAD, PENDING_EXCEPTION);
781 CLEAR_PENDING_EXCEPTION;
782 {
783 EXCEPTION_MARK;
784 // Locks object, set state, and notify all waiting threads
785 set_initialization_state_and_notify(initialization_error, THREAD);
786 CLEAR_PENDING_EXCEPTION;
787 }
788 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
789 THROW_OOP(e());
790 }
791 }
792
793
794 // Look for aot compiled methods for this klass, including class initializer.
795 AOTLoader::load_for_klass(this, THREAD);
796
797 // Step 8
798 {
799 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
800 JavaThread* jt = (JavaThread*)THREAD;
801 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
802 // Timer includes any side effects of class initialization (resolution,
803 // etc), but not recursive entry into call_class_initializer().
804 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
805 ClassLoader::perf_class_init_selftime(),
806 ClassLoader::perf_classes_inited(),
807 jt->get_thread_stat()->perf_recursion_counts_addr(),
808 jt->get_thread_stat()->perf_timers_addr(),
809 PerfClassTraceTime::CLASS_CLINIT);
810 call_class_initializer(THREAD);
811 }
812
813 // Step 9
814 if (!HAS_PENDING_EXCEPTION) {
815 set_initialization_state_and_notify(fully_initialized, CHECK);
816 {
817 debug_only(vtable().verify(tty, true);)
818 }
819 }
820 else {
821 // Step 10 and 11
822 Handle e(THREAD, PENDING_EXCEPTION);
823 CLEAR_PENDING_EXCEPTION;
824 // JVMTI has already reported the pending exception
825 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
826 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
827 {
828 EXCEPTION_MARK;
829 set_initialization_state_and_notify(initialization_error, THREAD);
830 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
831 // JVMTI has already reported the pending exception
832 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
833 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
834 }
835 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
836 if (e->is_a(SystemDictionary::Error_klass())) {
837 THROW_OOP(e());
838 } else {
839 JavaCallArguments args(e);
840 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
841 vmSymbols::throwable_void_signature(),
842 &args);
843 }
844 }
845 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
846 }
847
848
849 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
850 Handle h_init_lock(THREAD, init_lock());
851 if (h_init_lock() != NULL) {
852 ObjectLocker ol(h_init_lock, THREAD);
853 set_init_state(state);
854 fence_and_clear_init_lock();
855 ol.notify_all(CHECK);
856 } else {
857 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
858 set_init_state(state);
859 }
860 }
861
862 // The embedded _implementor field can only record one implementor.
863 // When there are more than one implementors, the _implementor field
864 // is set to the interface Klass* itself. Following are the possible
865 // values for the _implementor field:
866 // NULL - no implementor
867 // implementor Klass* - one implementor
868 // self - more than one implementor
869 //
870 // The _implementor field only exists for interfaces.
871 void InstanceKlass::add_implementor(Klass* k) {
872 assert(Compile_lock->owned_by_self(), "");
873 assert(is_interface(), "not interface");
874 // Filter out my subinterfaces.
875 // (Note: Interfaces are never on the subklass list.)
876 if (InstanceKlass::cast(k)->is_interface()) return;
877
878 // Filter out subclasses whose supers already implement me.
879 // (Note: CHA must walk subclasses of direct implementors
880 // in order to locate indirect implementors.)
881 Klass* sk = k->super();
882 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
883 // We only need to check one immediate superclass, since the
884 // implements_interface query looks at transitive_interfaces.
885 // Any supers of the super have the same (or fewer) transitive_interfaces.
886 return;
887
888 Klass* ik = implementor();
889 if (ik == NULL) {
890 set_implementor(k);
891 } else if (ik != this) {
892 // There is already an implementor. Use itself as an indicator of
893 // more than one implementors.
894 set_implementor(this);
895 }
896
897 // The implementor also implements the transitive_interfaces
898 for (int index = 0; index < local_interfaces()->length(); index++) {
899 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
900 }
901 }
902
903 void InstanceKlass::init_implementor() {
904 if (is_interface()) {
905 set_implementor(NULL);
906 }
907 }
908
909
910 void InstanceKlass::process_interfaces(Thread *thread) {
911 // link this class into the implementors list of every interface it implements
912 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
913 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
914 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
915 assert(interf->is_interface(), "expected interface");
916 interf->add_implementor(this);
917 }
918 }
919
920 bool InstanceKlass::can_be_primary_super_slow() const {
921 if (is_interface())
922 return false;
923 else
924 return Klass::can_be_primary_super_slow();
925 }
926
927 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
928 // The secondaries are the implemented interfaces.
929 Array<Klass*>* interfaces = transitive_interfaces();
930 int num_secondaries = num_extra_slots + interfaces->length();
931 if (num_secondaries == 0) {
932 // Must share this for correct bootstrapping!
933 set_secondary_supers(Universe::the_empty_klass_array());
934 return NULL;
935 } else if (num_extra_slots == 0) {
936 // The secondary super list is exactly the same as the transitive interfaces.
937 // Redefine classes has to be careful not to delete this!
938 set_secondary_supers(interfaces);
939 return NULL;
940 } else {
941 // Copy transitive interfaces to a temporary growable array to be constructed
942 // into the secondary super list with extra slots.
943 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
944 for (int i = 0; i < interfaces->length(); i++) {
945 secondaries->push(interfaces->at(i));
946 }
947 return secondaries;
948 }
949 }
950
951 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
952 if (k->is_interface()) {
953 return implements_interface(k);
954 } else {
955 return Klass::compute_is_subtype_of(k);
956 }
957 }
958
959 bool InstanceKlass::implements_interface(Klass* k) const {
960 if (this == k) return true;
961 assert(k->is_interface(), "should be an interface class");
962 for (int i = 0; i < transitive_interfaces()->length(); i++) {
963 if (transitive_interfaces()->at(i) == k) {
964 return true;
965 }
966 }
967 return false;
968 }
969
970 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
971 // Verify direct super interface
972 if (this == k) return true;
973 assert(k->is_interface(), "should be an interface class");
974 for (int i = 0; i < local_interfaces()->length(); i++) {
975 if (local_interfaces()->at(i) == k) {
976 return true;
977 }
978 }
979 return false;
980 }
981
982 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
983 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
984 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
985 report_java_out_of_memory("Requested array size exceeds VM limit");
986 JvmtiExport::post_array_size_exhausted();
987 THROW_OOP_0(Universe::out_of_memory_error_array_size());
988 }
989 int size = objArrayOopDesc::object_size(length);
990 Klass* ak = array_klass(n, CHECK_NULL);
991 objArrayOop o =
992 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
993 return o;
994 }
995
996 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
997 if (TraceFinalizerRegistration) {
998 tty->print("Registered ");
999 i->print_value_on(tty);
1000 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1001 }
1002 instanceHandle h_i(THREAD, i);
1003 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1004 JavaValue result(T_VOID);
1005 JavaCallArguments args(h_i);
1006 methodHandle mh (THREAD, Universe::finalizer_register_method());
1007 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1008 return h_i();
1009 }
1010
1011 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1012 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1013 int size = size_helper(); // Query before forming handle.
1014
1015 instanceOop i;
1016
1017 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1018 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1019 i = register_finalizer(i, CHECK_NULL);
1020 }
1021 return i;
1022 }
1023
1024 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1025 if (is_interface() || is_abstract()) {
1026 ResourceMark rm(THREAD);
1027 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1028 : vmSymbols::java_lang_InstantiationException(), external_name());
1029 }
1030 if (this == SystemDictionary::Class_klass()) {
1031 ResourceMark rm(THREAD);
1032 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1033 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1034 }
1035 }
1036
1037 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1038 // Need load-acquire for lock-free read
1039 if (array_klasses_acquire() == NULL) {
1040 if (or_null) return NULL;
1041
1042 ResourceMark rm;
1043 JavaThread *jt = (JavaThread *)THREAD;
1044 {
1045 // Atomic creation of array_klasses
1046 MutexLocker mc(Compile_lock, THREAD); // for vtables
1047 MutexLocker ma(MultiArray_lock, THREAD);
1048
1049 // Check if update has already taken place
1050 if (array_klasses() == NULL) {
1051 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1052 // use 'release' to pair with lock-free load
1053 release_set_array_klasses(k);
1054 }
1055 }
1056 }
1057 // _this will always be set at this point
1058 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1059 if (or_null) {
1060 return oak->array_klass_or_null(n);
1061 }
1062 return oak->array_klass(n, THREAD);
1063 }
1064
1065 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1066 return array_klass_impl(or_null, 1, THREAD);
1067 }
1068
1069 static int call_class_initializer_counter = 0; // for debugging
1070
1071 Method* InstanceKlass::class_initializer() const {
1072 Method* clinit = find_method(
1073 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1074 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1075 return clinit;
1076 }
1077 return NULL;
1078 }
1079
1080 void InstanceKlass::call_class_initializer(TRAPS) {
1081 if (ReplayCompiles &&
1082 (ReplaySuppressInitializers == 1 ||
1083 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1084 // Hide the existence of the initializer for the purpose of replaying the compile
1085 return;
1086 }
1087
1088 methodHandle h_method(THREAD, class_initializer());
1089 assert(!is_initialized(), "we cannot initialize twice");
1090 LogTarget(Info, class, init) lt;
1091 if (lt.is_enabled()) {
1092 ResourceMark rm;
1093 LogStream ls(lt);
1094 ls.print("%d Initializing ", call_class_initializer_counter++);
1095 name()->print_value_on(&ls);
1096 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1097 }
1098 if (h_method() != NULL) {
1099 JavaCallArguments args; // No arguments
1100 JavaValue result(T_VOID);
1101 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1102 }
1103 }
1104
1105
1106 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1107 InterpreterOopMap* entry_for) {
1108 // Lazily create the _oop_map_cache at first request
1109 // Lock-free access requires load_ptr_acquire.
1110 OopMapCache* oop_map_cache =
1111 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache));
1112 if (oop_map_cache == NULL) {
1113 MutexLocker x(OopMapCacheAlloc_lock);
1114 // Check if _oop_map_cache was allocated while we were waiting for this lock
1115 if ((oop_map_cache = _oop_map_cache) == NULL) {
1116 oop_map_cache = new OopMapCache();
1117 // Ensure _oop_map_cache is stable, since it is examined without a lock
1118 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache);
1119 }
1120 }
1121 // _oop_map_cache is constant after init; lookup below does its own locking.
1122 oop_map_cache->lookup(method, bci, entry_for);
1123 }
1124
1125
1126 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1127 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1128 Symbol* f_name = fs.name();
1129 Symbol* f_sig = fs.signature();
1130 if (f_name == name && f_sig == sig) {
1131 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1132 return true;
1133 }
1134 }
1135 return false;
1136 }
1137
1138
1139 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1140 const int n = local_interfaces()->length();
1141 for (int i = 0; i < n; i++) {
1142 Klass* intf1 = local_interfaces()->at(i);
1143 assert(intf1->is_interface(), "just checking type");
1144 // search for field in current interface
1145 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1146 assert(fd->is_static(), "interface field must be static");
1147 return intf1;
1148 }
1149 // search for field in direct superinterfaces
1150 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1151 if (intf2 != NULL) return intf2;
1152 }
1153 // otherwise field lookup fails
1154 return NULL;
1155 }
1156
1157
1158 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1159 // search order according to newest JVM spec (5.4.3.2, p.167).
1160 // 1) search for field in current klass
1161 if (find_local_field(name, sig, fd)) {
1162 return const_cast<InstanceKlass*>(this);
1163 }
1164 // 2) search for field recursively in direct superinterfaces
1165 { Klass* intf = find_interface_field(name, sig, fd);
1166 if (intf != NULL) return intf;
1167 }
1168 // 3) apply field lookup recursively if superclass exists
1169 { Klass* supr = super();
1170 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1171 }
1172 // 4) otherwise field lookup fails
1173 return NULL;
1174 }
1175
1176
1177 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1178 // search order according to newest JVM spec (5.4.3.2, p.167).
1179 // 1) search for field in current klass
1180 if (find_local_field(name, sig, fd)) {
1181 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1182 }
1183 // 2) search for field recursively in direct superinterfaces
1184 if (is_static) {
1185 Klass* intf = find_interface_field(name, sig, fd);
1186 if (intf != NULL) return intf;
1187 }
1188 // 3) apply field lookup recursively if superclass exists
1189 { Klass* supr = super();
1190 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1191 }
1192 // 4) otherwise field lookup fails
1193 return NULL;
1194 }
1195
1196
1197 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1198 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1199 if (fs.offset() == offset) {
1200 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1201 if (fd->is_static() == is_static) return true;
1202 }
1203 }
1204 return false;
1205 }
1206
1207
1208 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1209 Klass* klass = const_cast<InstanceKlass*>(this);
1210 while (klass != NULL) {
1211 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1212 return true;
1213 }
1214 klass = klass->super();
1215 }
1216 return false;
1217 }
1218
1219
1220 void InstanceKlass::methods_do(void f(Method* method)) {
1221 // Methods aren't stable until they are loaded. This can be read outside
1222 // a lock through the ClassLoaderData for profiling
1223 if (!is_loaded()) {
1224 return;
1225 }
1226
1227 int len = methods()->length();
1228 for (int index = 0; index < len; index++) {
1229 Method* m = methods()->at(index);
1230 assert(m->is_method(), "must be method");
1231 f(m);
1232 }
1233 }
1234
1235
1236 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1237 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1238 if (fs.access_flags().is_static()) {
1239 fieldDescriptor& fd = fs.field_descriptor();
1240 cl->do_field(&fd);
1241 }
1242 }
1243 }
1244
1245
1246 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1247 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1248 if (fs.access_flags().is_static()) {
1249 fieldDescriptor& fd = fs.field_descriptor();
1250 f(&fd, mirror, CHECK);
1251 }
1252 }
1253 }
1254
1255
1256 static int compare_fields_by_offset(int* a, int* b) {
1257 return a[0] - b[0];
1258 }
1259
1260 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1261 InstanceKlass* super = superklass();
1262 if (super != NULL) {
1263 super->do_nonstatic_fields(cl);
1264 }
1265 fieldDescriptor fd;
1266 int length = java_fields_count();
1267 // In DebugInfo nonstatic fields are sorted by offset.
1268 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1269 int j = 0;
1270 for (int i = 0; i < length; i += 1) {
1271 fd.reinitialize(this, i);
1272 if (!fd.is_static()) {
1273 fields_sorted[j + 0] = fd.offset();
1274 fields_sorted[j + 1] = i;
1275 j += 2;
1276 }
1277 }
1278 if (j > 0) {
1279 length = j;
1280 // _sort_Fn is defined in growableArray.hpp.
1281 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1282 for (int i = 0; i < length; i += 2) {
1283 fd.reinitialize(this, fields_sorted[i + 1]);
1284 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1285 cl->do_field(&fd);
1286 }
1287 }
1288 FREE_C_HEAP_ARRAY(int, fields_sorted);
1289 }
1290
1291
1292 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1293 if (array_klasses() != NULL)
1294 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1295 }
1296
1297 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1298 if (array_klasses() != NULL)
1299 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1300 }
1301
1302 #ifdef ASSERT
1303 static int linear_search(const Array<Method*>* methods,
1304 const Symbol* name,
1305 const Symbol* signature) {
1306 const int len = methods->length();
1307 for (int index = 0; index < len; index++) {
1308 const Method* const m = methods->at(index);
1309 assert(m->is_method(), "must be method");
1310 if (m->signature() == signature && m->name() == name) {
1311 return index;
1312 }
1313 }
1314 return -1;
1315 }
1316 #endif
1317
1318 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1319 int len = methods->length();
1320 // methods are sorted, so do binary search
1321 int l = 0;
1322 int h = len - 1;
1323 while (l <= h) {
1324 int mid = (l + h) >> 1;
1325 Method* m = methods->at(mid);
1326 assert(m->is_method(), "must be method");
1327 int res = m->name()->fast_compare(name);
1328 if (res == 0) {
1329 return mid;
1330 } else if (res < 0) {
1331 l = mid + 1;
1332 } else {
1333 h = mid - 1;
1334 }
1335 }
1336 return -1;
1337 }
1338
1339 // find_method looks up the name/signature in the local methods array
1340 Method* InstanceKlass::find_method(const Symbol* name,
1341 const Symbol* signature) const {
1342 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1343 }
1344
1345 Method* InstanceKlass::find_method_impl(const Symbol* name,
1346 const Symbol* signature,
1347 OverpassLookupMode overpass_mode,
1348 StaticLookupMode static_mode,
1349 PrivateLookupMode private_mode) const {
1350 return InstanceKlass::find_method_impl(methods(),
1351 name,
1352 signature,
1353 overpass_mode,
1354 static_mode,
1355 private_mode);
1356 }
1357
1358 // find_instance_method looks up the name/signature in the local methods array
1359 // and skips over static methods
1360 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1361 const Symbol* name,
1362 const Symbol* signature) {
1363 Method* const meth = InstanceKlass::find_method_impl(methods,
1364 name,
1365 signature,
1366 find_overpass,
1367 skip_static,
1368 find_private);
1369 assert(((meth == NULL) || !meth->is_static()),
1370 "find_instance_method should have skipped statics");
1371 return meth;
1372 }
1373
1374 // find_instance_method looks up the name/signature in the local methods array
1375 // and skips over static methods
1376 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1377 return InstanceKlass::find_instance_method(methods(), name, signature);
1378 }
1379
1380 // Find looks up the name/signature in the local methods array
1381 // and filters on the overpass, static and private flags
1382 // This returns the first one found
1383 // note that the local methods array can have up to one overpass, one static
1384 // and one instance (private or not) with the same name/signature
1385 Method* InstanceKlass::find_local_method(const Symbol* name,
1386 const Symbol* signature,
1387 OverpassLookupMode overpass_mode,
1388 StaticLookupMode static_mode,
1389 PrivateLookupMode private_mode) const {
1390 return InstanceKlass::find_method_impl(methods(),
1391 name,
1392 signature,
1393 overpass_mode,
1394 static_mode,
1395 private_mode);
1396 }
1397
1398 // Find looks up the name/signature in the local methods array
1399 // and filters on the overpass, static and private flags
1400 // This returns the first one found
1401 // note that the local methods array can have up to one overpass, one static
1402 // and one instance (private or not) with the same name/signature
1403 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1404 const Symbol* name,
1405 const Symbol* signature,
1406 OverpassLookupMode overpass_mode,
1407 StaticLookupMode static_mode,
1408 PrivateLookupMode private_mode) {
1409 return InstanceKlass::find_method_impl(methods,
1410 name,
1411 signature,
1412 overpass_mode,
1413 static_mode,
1414 private_mode);
1415 }
1416
1417 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1418 const Symbol* name,
1419 const Symbol* signature) {
1420 return InstanceKlass::find_method_impl(methods,
1421 name,
1422 signature,
1423 find_overpass,
1424 find_static,
1425 find_private);
1426 }
1427
1428 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1429 const Symbol* name,
1430 const Symbol* signature,
1431 OverpassLookupMode overpass_mode,
1432 StaticLookupMode static_mode,
1433 PrivateLookupMode private_mode) {
1434 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1435 return hit >= 0 ? methods->at(hit): NULL;
1436 }
1437
1438 // true if method matches signature and conforms to skipping_X conditions.
1439 static bool method_matches(const Method* m,
1440 const Symbol* signature,
1441 bool skipping_overpass,
1442 bool skipping_static,
1443 bool skipping_private) {
1444 return ((m->signature() == signature) &&
1445 (!skipping_overpass || !m->is_overpass()) &&
1446 (!skipping_static || !m->is_static()) &&
1447 (!skipping_private || !m->is_private()));
1448 }
1449
1450 // Used directly for default_methods to find the index into the
1451 // default_vtable_indices, and indirectly by find_method
1452 // find_method_index looks in the local methods array to return the index
1453 // of the matching name/signature. If, overpass methods are being ignored,
1454 // the search continues to find a potential non-overpass match. This capability
1455 // is important during method resolution to prefer a static method, for example,
1456 // over an overpass method.
1457 // There is the possibility in any _method's array to have the same name/signature
1458 // for a static method, an overpass method and a local instance method
1459 // To correctly catch a given method, the search criteria may need
1460 // to explicitly skip the other two. For local instance methods, it
1461 // is often necessary to skip private methods
1462 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1463 const Symbol* name,
1464 const Symbol* signature,
1465 OverpassLookupMode overpass_mode,
1466 StaticLookupMode static_mode,
1467 PrivateLookupMode private_mode) {
1468 const bool skipping_overpass = (overpass_mode == skip_overpass);
1469 const bool skipping_static = (static_mode == skip_static);
1470 const bool skipping_private = (private_mode == skip_private);
1471 const int hit = binary_search(methods, name);
1472 if (hit != -1) {
1473 const Method* const m = methods->at(hit);
1474
1475 // Do linear search to find matching signature. First, quick check
1476 // for common case, ignoring overpasses if requested.
1477 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1478 return hit;
1479 }
1480
1481 // search downwards through overloaded methods
1482 int i;
1483 for (i = hit - 1; i >= 0; --i) {
1484 const Method* const m = methods->at(i);
1485 assert(m->is_method(), "must be method");
1486 if (m->name() != name) {
1487 break;
1488 }
1489 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1490 return i;
1491 }
1492 }
1493 // search upwards
1494 for (i = hit + 1; i < methods->length(); ++i) {
1495 const Method* const m = methods->at(i);
1496 assert(m->is_method(), "must be method");
1497 if (m->name() != name) {
1498 break;
1499 }
1500 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1501 return i;
1502 }
1503 }
1504 // not found
1505 #ifdef ASSERT
1506 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1507 linear_search(methods, name, signature);
1508 assert(-1 == index, "binary search should have found entry %d", index);
1509 #endif
1510 }
1511 return -1;
1512 }
1513
1514 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1515 return find_method_by_name(methods(), name, end);
1516 }
1517
1518 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1519 const Symbol* name,
1520 int* end_ptr) {
1521 assert(end_ptr != NULL, "just checking");
1522 int start = binary_search(methods, name);
1523 int end = start + 1;
1524 if (start != -1) {
1525 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1526 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1527 *end_ptr = end;
1528 return start;
1529 }
1530 return -1;
1531 }
1532
1533 // uncached_lookup_method searches both the local class methods array and all
1534 // superclasses methods arrays, skipping any overpass methods in superclasses.
1535 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1536 const Symbol* signature,
1537 OverpassLookupMode overpass_mode) const {
1538 OverpassLookupMode overpass_local_mode = overpass_mode;
1539 const Klass* klass = this;
1540 while (klass != NULL) {
1541 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1542 signature,
1543 overpass_local_mode,
1544 find_static,
1545 find_private);
1546 if (method != NULL) {
1547 return method;
1548 }
1549 klass = klass->super();
1550 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1551 }
1552 return NULL;
1553 }
1554
1555 #ifdef ASSERT
1556 // search through class hierarchy and return true if this class or
1557 // one of the superclasses was redefined
1558 bool InstanceKlass::has_redefined_this_or_super() const {
1559 const Klass* klass = this;
1560 while (klass != NULL) {
1561 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1562 return true;
1563 }
1564 klass = klass->super();
1565 }
1566 return false;
1567 }
1568 #endif
1569
1570 // lookup a method in the default methods list then in all transitive interfaces
1571 // Do NOT return private or static methods
1572 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1573 Symbol* signature) const {
1574 Method* m = NULL;
1575 if (default_methods() != NULL) {
1576 m = find_method(default_methods(), name, signature);
1577 }
1578 // Look up interfaces
1579 if (m == NULL) {
1580 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1581 }
1582 return m;
1583 }
1584
1585 // lookup a method in all the interfaces that this class implements
1586 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1587 // They should only be found in the initial InterfaceMethodRef
1588 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1589 Symbol* signature,
1590 DefaultsLookupMode defaults_mode) const {
1591 Array<Klass*>* all_ifs = transitive_interfaces();
1592 int num_ifs = all_ifs->length();
1593 InstanceKlass *ik = NULL;
1594 for (int i = 0; i < num_ifs; i++) {
1595 ik = InstanceKlass::cast(all_ifs->at(i));
1596 Method* m = ik->lookup_method(name, signature);
1597 if (m != NULL && m->is_public() && !m->is_static() &&
1598 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1599 return m;
1600 }
1601 }
1602 return NULL;
1603 }
1604
1605 /* jni_id_for_impl for jfieldIds only */
1606 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1607 MutexLocker ml(JfieldIdCreation_lock);
1608 // Retry lookup after we got the lock
1609 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1610 if (probe == NULL) {
1611 // Slow case, allocate new static field identifier
1612 probe = new JNIid(this, offset, jni_ids());
1613 set_jni_ids(probe);
1614 }
1615 return probe;
1616 }
1617
1618
1619 /* jni_id_for for jfieldIds only */
1620 JNIid* InstanceKlass::jni_id_for(int offset) {
1621 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1622 if (probe == NULL) {
1623 probe = jni_id_for_impl(offset);
1624 }
1625 return probe;
1626 }
1627
1628 u2 InstanceKlass::enclosing_method_data(int offset) const {
1629 const Array<jushort>* const inner_class_list = inner_classes();
1630 if (inner_class_list == NULL) {
1631 return 0;
1632 }
1633 const int length = inner_class_list->length();
1634 if (length % inner_class_next_offset == 0) {
1635 return 0;
1636 }
1637 const int index = length - enclosing_method_attribute_size;
1638 assert(offset < enclosing_method_attribute_size, "invalid offset");
1639 return inner_class_list->at(index + offset);
1640 }
1641
1642 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1643 u2 method_index) {
1644 Array<jushort>* inner_class_list = inner_classes();
1645 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1646 int length = inner_class_list->length();
1647 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1648 int index = length - enclosing_method_attribute_size;
1649 inner_class_list->at_put(
1650 index + enclosing_method_class_index_offset, class_index);
1651 inner_class_list->at_put(
1652 index + enclosing_method_method_index_offset, method_index);
1653 }
1654 }
1655
1656 // Lookup or create a jmethodID.
1657 // This code is called by the VMThread and JavaThreads so the
1658 // locking has to be done very carefully to avoid deadlocks
1659 // and/or other cache consistency problems.
1660 //
1661 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1662 size_t idnum = (size_t)method_h->method_idnum();
1663 jmethodID* jmeths = methods_jmethod_ids_acquire();
1664 size_t length = 0;
1665 jmethodID id = NULL;
1666
1667 // We use a double-check locking idiom here because this cache is
1668 // performance sensitive. In the normal system, this cache only
1669 // transitions from NULL to non-NULL which is safe because we use
1670 // release_set_methods_jmethod_ids() to advertise the new cache.
1671 // A partially constructed cache should never be seen by a racing
1672 // thread. We also use release_store_ptr() to save a new jmethodID
1673 // in the cache so a partially constructed jmethodID should never be
1674 // seen either. Cache reads of existing jmethodIDs proceed without a
1675 // lock, but cache writes of a new jmethodID requires uniqueness and
1676 // creation of the cache itself requires no leaks so a lock is
1677 // generally acquired in those two cases.
1678 //
1679 // If the RedefineClasses() API has been used, then this cache can
1680 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1681 // Cache creation requires no leaks and we require safety between all
1682 // cache accesses and freeing of the old cache so a lock is generally
1683 // acquired when the RedefineClasses() API has been used.
1684
1685 if (jmeths != NULL) {
1686 // the cache already exists
1687 if (!idnum_can_increment()) {
1688 // the cache can't grow so we can just get the current values
1689 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1690 } else {
1691 // cache can grow so we have to be more careful
1692 if (Threads::number_of_threads() == 0 ||
1693 SafepointSynchronize::is_at_safepoint()) {
1694 // we're single threaded or at a safepoint - no locking needed
1695 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1696 } else {
1697 MutexLocker ml(JmethodIdCreation_lock);
1698 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1699 }
1700 }
1701 }
1702 // implied else:
1703 // we need to allocate a cache so default length and id values are good
1704
1705 if (jmeths == NULL || // no cache yet
1706 length <= idnum || // cache is too short
1707 id == NULL) { // cache doesn't contain entry
1708
1709 // This function can be called by the VMThread so we have to do all
1710 // things that might block on a safepoint before grabbing the lock.
1711 // Otherwise, we can deadlock with the VMThread or have a cache
1712 // consistency issue. These vars keep track of what we might have
1713 // to free after the lock is dropped.
1714 jmethodID to_dealloc_id = NULL;
1715 jmethodID* to_dealloc_jmeths = NULL;
1716
1717 // may not allocate new_jmeths or use it if we allocate it
1718 jmethodID* new_jmeths = NULL;
1719 if (length <= idnum) {
1720 // allocate a new cache that might be used
1721 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1722 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1723 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1724 // cache size is stored in element[0], other elements offset by one
1725 new_jmeths[0] = (jmethodID)size;
1726 }
1727
1728 // allocate a new jmethodID that might be used
1729 jmethodID new_id = NULL;
1730 if (method_h->is_old() && !method_h->is_obsolete()) {
1731 // The method passed in is old (but not obsolete), we need to use the current version
1732 Method* current_method = method_with_idnum((int)idnum);
1733 assert(current_method != NULL, "old and but not obsolete, so should exist");
1734 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1735 } else {
1736 // It is the current version of the method or an obsolete method,
1737 // use the version passed in
1738 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1739 }
1740
1741 if (Threads::number_of_threads() == 0 ||
1742 SafepointSynchronize::is_at_safepoint()) {
1743 // we're single threaded or at a safepoint - no locking needed
1744 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1745 &to_dealloc_id, &to_dealloc_jmeths);
1746 } else {
1747 MutexLocker ml(JmethodIdCreation_lock);
1748 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1749 &to_dealloc_id, &to_dealloc_jmeths);
1750 }
1751
1752 // The lock has been dropped so we can free resources.
1753 // Free up either the old cache or the new cache if we allocated one.
1754 if (to_dealloc_jmeths != NULL) {
1755 FreeHeap(to_dealloc_jmeths);
1756 }
1757 // free up the new ID since it wasn't needed
1758 if (to_dealloc_id != NULL) {
1759 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1760 }
1761 }
1762 return id;
1763 }
1764
1765 // Figure out how many jmethodIDs haven't been allocated, and make
1766 // sure space for them is pre-allocated. This makes getting all
1767 // method ids much, much faster with classes with more than 8
1768 // methods, and has a *substantial* effect on performance with jvmti
1769 // code that loads all jmethodIDs for all classes.
1770 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1771 int new_jmeths = 0;
1772 int length = methods()->length();
1773 for (int index = start_offset; index < length; index++) {
1774 Method* m = methods()->at(index);
1775 jmethodID id = m->find_jmethod_id_or_null();
1776 if (id == NULL) {
1777 new_jmeths++;
1778 }
1779 }
1780 if (new_jmeths != 0) {
1781 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1782 }
1783 }
1784
1785 // Common code to fetch the jmethodID from the cache or update the
1786 // cache with the new jmethodID. This function should never do anything
1787 // that causes the caller to go to a safepoint or we can deadlock with
1788 // the VMThread or have cache consistency issues.
1789 //
1790 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1791 size_t idnum, jmethodID new_id,
1792 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1793 jmethodID** to_dealloc_jmeths_p) {
1794 assert(new_id != NULL, "sanity check");
1795 assert(to_dealloc_id_p != NULL, "sanity check");
1796 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1797 assert(Threads::number_of_threads() == 0 ||
1798 SafepointSynchronize::is_at_safepoint() ||
1799 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1800
1801 // reacquire the cache - we are locked, single threaded or at a safepoint
1802 jmethodID* jmeths = methods_jmethod_ids_acquire();
1803 jmethodID id = NULL;
1804 size_t length = 0;
1805
1806 if (jmeths == NULL || // no cache yet
1807 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1808 if (jmeths != NULL) {
1809 // copy any existing entries from the old cache
1810 for (size_t index = 0; index < length; index++) {
1811 new_jmeths[index+1] = jmeths[index+1];
1812 }
1813 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1814 }
1815 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1816 } else {
1817 // fetch jmethodID (if any) from the existing cache
1818 id = jmeths[idnum+1];
1819 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1820 }
1821 if (id == NULL) {
1822 // No matching jmethodID in the existing cache or we have a new
1823 // cache or we just grew the cache. This cache write is done here
1824 // by the first thread to win the foot race because a jmethodID
1825 // needs to be unique once it is generally available.
1826 id = new_id;
1827
1828 // The jmethodID cache can be read while unlocked so we have to
1829 // make sure the new jmethodID is complete before installing it
1830 // in the cache.
1831 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1832 } else {
1833 *to_dealloc_id_p = new_id; // save new id for later delete
1834 }
1835 return id;
1836 }
1837
1838
1839 // Common code to get the jmethodID cache length and the jmethodID
1840 // value at index idnum if there is one.
1841 //
1842 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1843 size_t idnum, size_t *length_p, jmethodID* id_p) {
1844 assert(cache != NULL, "sanity check");
1845 assert(length_p != NULL, "sanity check");
1846 assert(id_p != NULL, "sanity check");
1847
1848 // cache size is stored in element[0], other elements offset by one
1849 *length_p = (size_t)cache[0];
1850 if (*length_p <= idnum) { // cache is too short
1851 *id_p = NULL;
1852 } else {
1853 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1854 }
1855 }
1856
1857
1858 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1859 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1860 size_t idnum = (size_t)method->method_idnum();
1861 jmethodID* jmeths = methods_jmethod_ids_acquire();
1862 size_t length; // length assigned as debugging crumb
1863 jmethodID id = NULL;
1864 if (jmeths != NULL && // If there is a cache
1865 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1866 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1867 }
1868 return id;
1869 }
1870
1871 inline DependencyContext InstanceKlass::dependencies() {
1872 DependencyContext dep_context(&_dep_context);
1873 return dep_context;
1874 }
1875
1876 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1877 return dependencies().mark_dependent_nmethods(changes);
1878 }
1879
1880 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1881 dependencies().add_dependent_nmethod(nm);
1882 }
1883
1884 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1885 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1886 }
1887
1888 #ifndef PRODUCT
1889 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1890 dependencies().print_dependent_nmethods(verbose);
1891 }
1892
1893 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1894 return dependencies().is_dependent_nmethod(nm);
1895 }
1896 #endif //PRODUCT
1897
1898 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1899 clean_implementors_list(is_alive);
1900 clean_method_data(is_alive);
1901
1902 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1903 DependencyContext dep_context(&_dep_context);
1904 dep_context.expunge_stale_entries();
1905 }
1906
1907 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1908 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1909 if (is_interface()) {
1910 if (ClassUnloading) {
1911 Klass* impl = implementor();
1912 if (impl != NULL) {
1913 if (!impl->is_loader_alive(is_alive)) {
1914 // remove this guy
1915 Klass** klass = adr_implementor();
1916 assert(klass != NULL, "null klass");
1917 if (klass != NULL) {
1918 *klass = NULL;
1919 }
1920 }
1921 }
1922 }
1923 }
1924 }
1925
1926 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1927 for (int m = 0; m < methods()->length(); m++) {
1928 MethodData* mdo = methods()->at(m)->method_data();
1929 if (mdo != NULL) {
1930 mdo->clean_method_data(is_alive);
1931 }
1932 }
1933 }
1934
1935 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
1936 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
1937 ResourceMark rm;
1938 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
1939 return false;
1940 }
1941
1942 Array<Klass*>* local_interfaces = this->local_interfaces();
1943 if (local_interfaces != NULL) {
1944 int length = local_interfaces->length();
1945 for (int i = 0; i < length; i++) {
1946 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
1947 if (!intf->has_passed_fingerprint_check()) {
1948 ResourceMark rm;
1949 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
1950 return false;
1951 }
1952 }
1953 }
1954
1955 return true;
1956 }
1957
1958 bool InstanceKlass::should_store_fingerprint() {
1959 #if INCLUDE_AOT
1960 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
1961 if (CalculateClassFingerprint) {
1962 // (1) We are running AOT to generate a shared library.
1963 return true;
1964 }
1965 if (DumpSharedSpaces) {
1966 // (2) We are running -Xshare:dump to create a shared archive
1967 return true;
1968 }
1969 #endif
1970
1971 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
1972 // but do not store the 64-bit fingerprint to save space.
1973 return false;
1974 }
1975
1976 bool InstanceKlass::has_stored_fingerprint() const {
1977 #if INCLUDE_AOT
1978 return should_store_fingerprint() || is_shared();
1979 #else
1980 return false;
1981 #endif
1982 }
1983
1984 uint64_t InstanceKlass::get_stored_fingerprint() const {
1985 address adr = adr_fingerprint();
1986 if (adr != NULL) {
1987 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
1988 }
1989 return 0;
1990 }
1991
1992 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
1993 address adr = adr_fingerprint();
1994 if (adr != NULL) {
1995 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
1996
1997 ResourceMark rm;
1998 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
1999 }
2000 }
2001
2002 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2003 Klass::metaspace_pointers_do(it);
2004
2005 if (log_is_enabled(Trace, cds)) {
2006 ResourceMark rm;
2007 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2008 }
2009
2010 it->push(&_annotations);
2011 it->push((Klass**)&_array_klasses);
2012 it->push(&_constants);
2013 it->push(&_inner_classes);
2014 it->push(&_array_name);
2015 #if INCLUDE_JVMTI
2016 it->push(&_previous_versions);
2017 #endif
2018 it->push(&_methods);
2019 it->push(&_default_methods);
2020 it->push(&_local_interfaces);
2021 it->push(&_transitive_interfaces);
2022 it->push(&_method_ordering);
2023 it->push(&_default_vtable_indices);
2024 it->push(&_fields);
2025
2026 if (itable_length() > 0) {
2027 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2028 int method_table_offset_in_words = ioe->offset()/wordSize;
2029 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2030 / itableOffsetEntry::size();
2031
2032 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2033 if (ioe->interface_klass() != NULL) {
2034 it->push(ioe->interface_klass_addr());
2035 itableMethodEntry* ime = ioe->first_method_entry(this);
2036 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2037 for (int index = 0; index < n; index ++) {
2038 it->push(ime[index].method_addr());
2039 }
2040 }
2041 }
2042 }
2043 }
2044
2045 void InstanceKlass::remove_unshareable_info() {
2046 Klass::remove_unshareable_info();
2047
2048 if (is_in_error_state()) {
2049 // Classes are attempted to link during dumping and may fail,
2050 // but these classes are still in the dictionary and class list in CLD.
2051 // Check in_error state first because in_error is > linked state, so
2052 // is_linked() is true.
2053 // If there's a linking error, there is nothing else to remove.
2054 return;
2055 }
2056
2057 // Unlink the class
2058 if (is_linked()) {
2059 unlink_class();
2060 }
2061 init_implementor();
2062
2063 constants()->remove_unshareable_info();
2064
2065 for (int i = 0; i < methods()->length(); i++) {
2066 Method* m = methods()->at(i);
2067 m->remove_unshareable_info();
2068 }
2069
2070 // do array classes also.
2071 if (array_klasses() != NULL) {
2072 array_klasses()->remove_unshareable_info();
2073 }
2074
2075 // These are not allocated from metaspace, but they should should all be empty
2076 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2077 guarantee(_source_debug_extension == NULL, "must be");
2078 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2079 guarantee(_osr_nmethods_head == NULL, "must be");
2080
2081 #if INCLUDE_JVMTI
2082 guarantee(_breakpoints == NULL, "must be");
2083 guarantee(_previous_versions == NULL, "must be");
2084 #endif
2085
2086 _init_thread = NULL;
2087 _methods_jmethod_ids = NULL;
2088 _jni_ids = NULL;
2089 _oop_map_cache = NULL;
2090 }
2091
2092 void InstanceKlass::remove_java_mirror() {
2093 Klass::remove_java_mirror();
2094
2095 // do array classes also.
2096 if (array_klasses() != NULL) {
2097 array_klasses()->remove_java_mirror();
2098 }
2099 }
2100
2101 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2102 set_package(loader_data, CHECK);
2103 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2104
2105 Array<Method*>* methods = this->methods();
2106 int num_methods = methods->length();
2107 for (int index2 = 0; index2 < num_methods; ++index2) {
2108 methodHandle m(THREAD, methods->at(index2));
2109 m->restore_unshareable_info(CHECK);
2110 }
2111 if (JvmtiExport::has_redefined_a_class()) {
2112 // Reinitialize vtable because RedefineClasses may have changed some
2113 // entries in this vtable for super classes so the CDS vtable might
2114 // point to old or obsolete entries. RedefineClasses doesn't fix up
2115 // vtables in the shared system dictionary, only the main one.
2116 // It also redefines the itable too so fix that too.
2117 ResourceMark rm(THREAD);
2118 vtable().initialize_vtable(false, CHECK);
2119 itable().initialize_itable(false, CHECK);
2120 }
2121
2122 // restore constant pool resolved references
2123 constants()->restore_unshareable_info(CHECK);
2124
2125 if (array_klasses() != NULL) {
2126 // Array classes have null protection domain.
2127 // --> see ArrayKlass::complete_create_array_klass()
2128 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2129 }
2130 }
2131
2132 // returns true IFF is_in_error_state() has been changed as a result of this call.
2133 bool InstanceKlass::check_sharing_error_state() {
2134 assert(DumpSharedSpaces, "should only be called during dumping");
2135 bool old_state = is_in_error_state();
2136
2137 if (!is_in_error_state()) {
2138 bool bad = false;
2139 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2140 if (sup->is_in_error_state()) {
2141 bad = true;
2142 break;
2143 }
2144 }
2145 if (!bad) {
2146 Array<Klass*>* interfaces = transitive_interfaces();
2147 for (int i = 0; i < interfaces->length(); i++) {
2148 Klass* iface = interfaces->at(i);
2149 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2150 bad = true;
2151 break;
2152 }
2153 }
2154 }
2155
2156 if (bad) {
2157 set_in_error_state();
2158 }
2159 }
2160
2161 return (old_state != is_in_error_state());
2162 }
2163
2164 #if INCLUDE_JVMTI
2165 static void clear_all_breakpoints(Method* m) {
2166 m->clear_all_breakpoints();
2167 }
2168 #endif
2169
2170 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2171 // notify the debugger
2172 if (JvmtiExport::should_post_class_unload()) {
2173 JvmtiExport::post_class_unload(ik);
2174 }
2175
2176 // notify ClassLoadingService of class unload
2177 ClassLoadingService::notify_class_unloaded(ik);
2178 }
2179
2180 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2181 // Clean up C heap
2182 ik->release_C_heap_structures();
2183 ik->constants()->release_C_heap_structures();
2184 }
2185
2186 void InstanceKlass::release_C_heap_structures() {
2187 // Can't release the constant pool here because the constant pool can be
2188 // deallocated separately from the InstanceKlass for default methods and
2189 // redefine classes.
2190
2191 // Deallocate oop map cache
2192 if (_oop_map_cache != NULL) {
2193 delete _oop_map_cache;
2194 _oop_map_cache = NULL;
2195 }
2196
2197 // Deallocate JNI identifiers for jfieldIDs
2198 JNIid::deallocate(jni_ids());
2199 set_jni_ids(NULL);
2200
2201 jmethodID* jmeths = methods_jmethod_ids_acquire();
2202 if (jmeths != (jmethodID*)NULL) {
2203 release_set_methods_jmethod_ids(NULL);
2204 FreeHeap(jmeths);
2205 }
2206
2207 // Release dependencies.
2208 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2209 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2210 // context can contain live dependencies, since there's a race between nmethod &
2211 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2212 // dependencies aren't removed from the context associated with the class (see
2213 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2214 // live dependencies pointing to unloaded nmethods and causes a crash in
2215 // DC::remove_all_dependents() when it touches unloaded nmethod.
2216 dependencies().wipe();
2217
2218 #if INCLUDE_JVMTI
2219 // Deallocate breakpoint records
2220 if (breakpoints() != 0x0) {
2221 methods_do(clear_all_breakpoints);
2222 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2223 }
2224
2225 // deallocate the cached class file
2226 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) {
2227 os::free(_cached_class_file);
2228 _cached_class_file = NULL;
2229 }
2230 #endif
2231
2232 // Decrement symbol reference counts associated with the unloaded class.
2233 if (_name != NULL) _name->decrement_refcount();
2234 // unreference array name derived from this class name (arrays of an unloaded
2235 // class can't be referenced anymore).
2236 if (_array_name != NULL) _array_name->decrement_refcount();
2237 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2238
2239 assert(_total_instanceKlass_count >= 1, "Sanity check");
2240 Atomic::dec(&_total_instanceKlass_count);
2241 }
2242
2243 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2244 if (array == NULL) {
2245 _source_debug_extension = NULL;
2246 } else {
2247 // Adding one to the attribute length in order to store a null terminator
2248 // character could cause an overflow because the attribute length is
2249 // already coded with an u4 in the classfile, but in practice, it's
2250 // unlikely to happen.
2251 assert((length+1) > length, "Overflow checking");
2252 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2253 for (int i = 0; i < length; i++) {
2254 sde[i] = array[i];
2255 }
2256 sde[length] = '\0';
2257 _source_debug_extension = sde;
2258 }
2259 }
2260
2261 address InstanceKlass::static_field_addr(int offset) {
2262 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2263 }
2264
2265
2266 const char* InstanceKlass::signature_name() const {
2267 int hash_len = 0;
2268 char hash_buf[40];
2269
2270 // If this is an anonymous class, append a hash to make the name unique
2271 if (is_anonymous()) {
2272 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2273 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2274 hash_len = (int)strlen(hash_buf);
2275 }
2276
2277 // Get the internal name as a c string
2278 const char* src = (const char*) (name()->as_C_string());
2279 const int src_length = (int)strlen(src);
2280
2281 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2282
2283 // Add L as type indicator
2284 int dest_index = 0;
2285 dest[dest_index++] = 'L';
2286
2287 // Add the actual class name
2288 for (int src_index = 0; src_index < src_length; ) {
2289 dest[dest_index++] = src[src_index++];
2290 }
2291
2292 // If we have a hash, append it
2293 for (int hash_index = 0; hash_index < hash_len; ) {
2294 dest[dest_index++] = hash_buf[hash_index++];
2295 }
2296
2297 // Add the semicolon and the NULL
2298 dest[dest_index++] = ';';
2299 dest[dest_index] = '\0';
2300 return dest;
2301 }
2302
2303 // Used to obtain the package name from a fully qualified class name.
2304 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2305 if (name == NULL) {
2306 return NULL;
2307 } else {
2308 if (name->utf8_length() <= 0) {
2309 return NULL;
2310 }
2311 ResourceMark rm;
2312 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2313 if (package_name == NULL) {
2314 return NULL;
2315 }
2316 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2317 return pkg_name;
2318 }
2319 }
2320
2321 ModuleEntry* InstanceKlass::module() const {
2322 if (!in_unnamed_package()) {
2323 return _package_entry->module();
2324 }
2325 const Klass* host = host_klass();
2326 if (host == NULL) {
2327 return class_loader_data()->unnamed_module();
2328 }
2329 return host->class_loader_data()->unnamed_module();
2330 }
2331
2332 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2333
2334 // ensure java/ packages only loaded by boot or platform builtin loaders
2335 Handle class_loader(THREAD, loader_data->class_loader());
2336 check_prohibited_package(name(), class_loader, CHECK);
2337
2338 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2339
2340 if (pkg_name != NULL && loader_data != NULL) {
2341
2342 // Find in class loader's package entry table.
2343 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2344
2345 // If the package name is not found in the loader's package
2346 // entry table, it is an indication that the package has not
2347 // been defined. Consider it defined within the unnamed module.
2348 if (_package_entry == NULL) {
2349 ResourceMark rm;
2350
2351 if (!ModuleEntryTable::javabase_defined()) {
2352 // Before java.base is defined during bootstrapping, define all packages in
2353 // the java.base module. If a non-java.base package is erroneously placed
2354 // in the java.base module it will be caught later when java.base
2355 // is defined by ModuleEntryTable::verify_javabase_packages check.
2356 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2357 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2358 } else {
2359 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2360 _package_entry = loader_data->packages()->lookup(pkg_name,
2361 loader_data->unnamed_module());
2362 }
2363
2364 // A package should have been successfully created
2365 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2366 name()->as_C_string(), loader_data->loader_name());
2367 }
2368
2369 if (log_is_enabled(Debug, module)) {
2370 ResourceMark rm;
2371 ModuleEntry* m = _package_entry->module();
2372 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2373 external_name(),
2374 pkg_name->as_C_string(),
2375 loader_data->loader_name(),
2376 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2377 }
2378 } else {
2379 ResourceMark rm;
2380 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2381 external_name(),
2382 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2383 UNNAMED_MODULE);
2384 }
2385 }
2386
2387
2388 // different versions of is_same_class_package
2389
2390 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2391 oop classloader1 = this->class_loader();
2392 PackageEntry* classpkg1 = this->package();
2393 if (class2->is_objArray_klass()) {
2394 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2395 }
2396
2397 oop classloader2;
2398 PackageEntry* classpkg2;
2399 if (class2->is_instance_klass()) {
2400 classloader2 = class2->class_loader();
2401 classpkg2 = class2->package();
2402 } else {
2403 assert(class2->is_typeArray_klass(), "should be type array");
2404 classloader2 = NULL;
2405 classpkg2 = NULL;
2406 }
2407
2408 // Same package is determined by comparing class loader
2409 // and package entries. Both must be the same. This rule
2410 // applies even to classes that are defined in the unnamed
2411 // package, they still must have the same class loader.
2412 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2413 return true;
2414 }
2415
2416 return false;
2417 }
2418
2419 // return true if this class and other_class are in the same package. Classloader
2420 // and classname information is enough to determine a class's package
2421 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2422 const Symbol* other_class_name) const {
2423 if (class_loader() != other_class_loader) {
2424 return false;
2425 }
2426 if (name()->fast_compare(other_class_name) == 0) {
2427 return true;
2428 }
2429
2430 {
2431 ResourceMark rm;
2432
2433 bool bad_class_name = false;
2434 const char* other_pkg =
2435 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2436 if (bad_class_name) {
2437 return false;
2438 }
2439 // Check that package_from_name() returns NULL, not "", if there is no package.
2440 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2441
2442 const Symbol* const this_package_name =
2443 this->package() != NULL ? this->package()->name() : NULL;
2444
2445 if (this_package_name == NULL || other_pkg == NULL) {
2446 // One of the two doesn't have a package. Only return true if the other
2447 // one also doesn't have a package.
2448 return (const char*)this_package_name == other_pkg;
2449 }
2450
2451 // Check if package is identical
2452 return this_package_name->equals(other_pkg);
2453 }
2454 }
2455
2456 // Returns true iff super_method can be overridden by a method in targetclassname
2457 // See JLS 3rd edition 8.4.6.1
2458 // Assumes name-signature match
2459 // "this" is InstanceKlass of super_method which must exist
2460 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2461 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2462 // Private methods can not be overridden
2463 if (super_method->is_private()) {
2464 return false;
2465 }
2466 // If super method is accessible, then override
2467 if ((super_method->is_protected()) ||
2468 (super_method->is_public())) {
2469 return true;
2470 }
2471 // Package-private methods are not inherited outside of package
2472 assert(super_method->is_package_private(), "must be package private");
2473 return(is_same_class_package(targetclassloader(), targetclassname));
2474 }
2475
2476 // Only boot and platform class loaders can define classes in "java/" packages.
2477 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2478 Handle class_loader,
2479 TRAPS) {
2480 if (!class_loader.is_null() &&
2481 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2482 class_name != NULL) {
2483 ResourceMark rm(THREAD);
2484 char* name = class_name->as_C_string();
2485 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2486 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2487 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2488 name = pkg_name->as_C_string();
2489 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2490 StringUtils::replace_no_expand(name, "/", ".");
2491 const char* msg_text1 = "Class loader (instance of): ";
2492 const char* msg_text2 = " tried to load prohibited package name: ";
2493 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2494 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2495 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2496 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2497 }
2498 }
2499 return;
2500 }
2501
2502 // tell if two classes have the same enclosing class (at package level)
2503 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2504 if (class2 == this) return true;
2505 if (!class2->is_instance_klass()) return false;
2506
2507 // must be in same package before we try anything else
2508 if (!is_same_class_package(class2))
2509 return false;
2510
2511 // As long as there is an outer_this.getEnclosingClass,
2512 // shift the search outward.
2513 const InstanceKlass* outer_this = this;
2514 for (;;) {
2515 // As we walk along, look for equalities between outer_this and class2.
2516 // Eventually, the walks will terminate as outer_this stops
2517 // at the top-level class around the original class.
2518 bool ignore_inner_is_member;
2519 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2520 CHECK_false);
2521 if (next == NULL) break;
2522 if (next == class2) return true;
2523 outer_this = InstanceKlass::cast(next);
2524 }
2525
2526 // Now do the same for class2.
2527 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2528 for (;;) {
2529 bool ignore_inner_is_member;
2530 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2531 CHECK_false);
2532 if (next == NULL) break;
2533 // Might as well check the new outer against all available values.
2534 if (next == this) return true;
2535 if (next == outer_this) return true;
2536 outer2 = InstanceKlass::cast(next);
2537 }
2538
2539 // If by this point we have not found an equality between the
2540 // two classes, we know they are in separate package members.
2541 return false;
2542 }
2543
2544 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2545 constantPoolHandle i_cp(THREAD, constants());
2546 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2547 int ioff = iter.inner_class_info_index();
2548 if (ioff != 0) {
2549 // Check to see if the name matches the class we're looking for
2550 // before attempting to find the class.
2551 if (i_cp->klass_name_at_matches(this, ioff)) {
2552 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2553 if (this == inner_klass) {
2554 *ooff = iter.outer_class_info_index();
2555 *noff = iter.inner_name_index();
2556 return true;
2557 }
2558 }
2559 }
2560 }
2561 return false;
2562 }
2563
2564 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2565 InstanceKlass* outer_klass = NULL;
2566 *inner_is_member = false;
2567 int ooff = 0, noff = 0;
2568 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2569 if (has_inner_classes_attr) {
2570 constantPoolHandle i_cp(THREAD, constants());
2571 if (ooff != 0) {
2572 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2573 outer_klass = InstanceKlass::cast(ok);
2574 *inner_is_member = true;
2575 }
2576 if (NULL == outer_klass) {
2577 // It may be anonymous; try for that.
2578 int encl_method_class_idx = enclosing_method_class_index();
2579 if (encl_method_class_idx != 0) {
2580 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2581 outer_klass = InstanceKlass::cast(ok);
2582 *inner_is_member = false;
2583 }
2584 }
2585 }
2586
2587 // If no inner class attribute found for this class.
2588 if (NULL == outer_klass) return NULL;
2589
2590 // Throws an exception if outer klass has not declared k as an inner klass
2591 // We need evidence that each klass knows about the other, or else
2592 // the system could allow a spoof of an inner class to gain access rights.
2593 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2594 return outer_klass;
2595 }
2596
2597 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2598 jint access = access_flags().as_int();
2599
2600 // But check if it happens to be member class.
2601 InnerClassesIterator iter(this);
2602 for (; !iter.done(); iter.next()) {
2603 int ioff = iter.inner_class_info_index();
2604 // Inner class attribute can be zero, skip it.
2605 // Strange but true: JVM spec. allows null inner class refs.
2606 if (ioff == 0) continue;
2607
2608 // only look at classes that are already loaded
2609 // since we are looking for the flags for our self.
2610 Symbol* inner_name = constants()->klass_name_at(ioff);
2611 if (name() == inner_name) {
2612 // This is really a member class.
2613 access = iter.inner_access_flags();
2614 break;
2615 }
2616 }
2617 // Remember to strip ACC_SUPER bit
2618 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2619 }
2620
2621 jint InstanceKlass::jvmti_class_status() const {
2622 jint result = 0;
2623
2624 if (is_linked()) {
2625 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2626 }
2627
2628 if (is_initialized()) {
2629 assert(is_linked(), "Class status is not consistent");
2630 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2631 }
2632 if (is_in_error_state()) {
2633 result |= JVMTI_CLASS_STATUS_ERROR;
2634 }
2635 return result;
2636 }
2637
2638 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2639 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2640 int method_table_offset_in_words = ioe->offset()/wordSize;
2641 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2642 / itableOffsetEntry::size();
2643
2644 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2645 // If the interface isn't implemented by the receiver class,
2646 // the VM should throw IncompatibleClassChangeError.
2647 if (cnt >= nof_interfaces) {
2648 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2649 }
2650
2651 Klass* ik = ioe->interface_klass();
2652 if (ik == holder) break;
2653 }
2654
2655 itableMethodEntry* ime = ioe->first_method_entry(this);
2656 Method* m = ime[index].method();
2657 if (m == NULL) {
2658 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2659 }
2660 return m;
2661 }
2662
2663
2664 #if INCLUDE_JVMTI
2665 // update default_methods for redefineclasses for methods that are
2666 // not yet in the vtable due to concurrent subclass define and superinterface
2667 // redefinition
2668 // Note: those in the vtable, should have been updated via adjust_method_entries
2669 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2670 // search the default_methods for uses of either obsolete or EMCP methods
2671 if (default_methods() != NULL) {
2672 for (int index = 0; index < default_methods()->length(); index ++) {
2673 Method* old_method = default_methods()->at(index);
2674 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2675 continue; // skip uninteresting entries
2676 }
2677 assert(!old_method->is_deleted(), "default methods may not be deleted");
2678
2679 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2680
2681 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2682 assert(old_method != new_method, "sanity check");
2683
2684 default_methods()->at_put(index, new_method);
2685 if (log_is_enabled(Info, redefine, class, update)) {
2686 ResourceMark rm;
2687 if (!(*trace_name_printed)) {
2688 log_info(redefine, class, update)
2689 ("adjust: klassname=%s default methods from name=%s",
2690 external_name(), old_method->method_holder()->external_name());
2691 *trace_name_printed = true;
2692 }
2693 log_debug(redefine, class, update, vtables)
2694 ("default method update: %s(%s) ",
2695 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2696 }
2697 }
2698 }
2699 }
2700 #endif // INCLUDE_JVMTI
2701
2702 // On-stack replacement stuff
2703 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2704 // only one compilation can be active
2705 {
2706 // This is a short non-blocking critical region, so the no safepoint check is ok.
2707 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2708 assert(n->is_osr_method(), "wrong kind of nmethod");
2709 n->set_osr_link(osr_nmethods_head());
2710 set_osr_nmethods_head(n);
2711 // Raise the highest osr level if necessary
2712 if (TieredCompilation) {
2713 Method* m = n->method();
2714 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2715 }
2716 }
2717
2718 // Get rid of the osr methods for the same bci that have lower levels.
2719 if (TieredCompilation) {
2720 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2721 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2722 if (inv != NULL && inv->is_in_use()) {
2723 inv->make_not_entrant();
2724 }
2725 }
2726 }
2727 }
2728
2729 // Remove osr nmethod from the list. Return true if found and removed.
2730 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2731 // This is a short non-blocking critical region, so the no safepoint check is ok.
2732 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2733 assert(n->is_osr_method(), "wrong kind of nmethod");
2734 nmethod* last = NULL;
2735 nmethod* cur = osr_nmethods_head();
2736 int max_level = CompLevel_none; // Find the max comp level excluding n
2737 Method* m = n->method();
2738 // Search for match
2739 bool found = false;
2740 while(cur != NULL && cur != n) {
2741 if (TieredCompilation && m == cur->method()) {
2742 // Find max level before n
2743 max_level = MAX2(max_level, cur->comp_level());
2744 }
2745 last = cur;
2746 cur = cur->osr_link();
2747 }
2748 nmethod* next = NULL;
2749 if (cur == n) {
2750 found = true;
2751 next = cur->osr_link();
2752 if (last == NULL) {
2753 // Remove first element
2754 set_osr_nmethods_head(next);
2755 } else {
2756 last->set_osr_link(next);
2757 }
2758 }
2759 n->set_osr_link(NULL);
2760 if (TieredCompilation) {
2761 cur = next;
2762 while (cur != NULL) {
2763 // Find max level after n
2764 if (m == cur->method()) {
2765 max_level = MAX2(max_level, cur->comp_level());
2766 }
2767 cur = cur->osr_link();
2768 }
2769 m->set_highest_osr_comp_level(max_level);
2770 }
2771 return found;
2772 }
2773
2774 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2775 // This is a short non-blocking critical region, so the no safepoint check is ok.
2776 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2777 nmethod* osr = osr_nmethods_head();
2778 int found = 0;
2779 while (osr != NULL) {
2780 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2781 if (osr->method() == m) {
2782 osr->mark_for_deoptimization();
2783 found++;
2784 }
2785 osr = osr->osr_link();
2786 }
2787 return found;
2788 }
2789
2790 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2791 // This is a short non-blocking critical region, so the no safepoint check is ok.
2792 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2793 nmethod* osr = osr_nmethods_head();
2794 nmethod* best = NULL;
2795 while (osr != NULL) {
2796 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2797 // There can be a time when a c1 osr method exists but we are waiting
2798 // for a c2 version. When c2 completes its osr nmethod we will trash
2799 // the c1 version and only be able to find the c2 version. However
2800 // while we overflow in the c1 code at back branches we don't want to
2801 // try and switch to the same code as we are already running
2802
2803 if (osr->method() == m &&
2804 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2805 if (match_level) {
2806 if (osr->comp_level() == comp_level) {
2807 // Found a match - return it.
2808 return osr;
2809 }
2810 } else {
2811 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2812 if (osr->comp_level() == CompLevel_highest_tier) {
2813 // Found the best possible - return it.
2814 return osr;
2815 }
2816 best = osr;
2817 }
2818 }
2819 }
2820 osr = osr->osr_link();
2821 }
2822 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2823 return best;
2824 }
2825 return NULL;
2826 }
2827
2828 // -----------------------------------------------------------------------------------------------------
2829 // Printing
2830
2831 #ifndef PRODUCT
2832
2833 #define BULLET " - "
2834
2835 static const char* state_names[] = {
2836 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2837 };
2838
2839 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2840 for (int i = 0; i < len; i++) {
2841 intptr_t e = start[i];
2842 st->print("%d : " INTPTR_FORMAT, i, e);
2843 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2844 st->print(" ");
2845 ((Metadata*)e)->print_value_on(st);
2846 }
2847 st->cr();
2848 }
2849 }
2850
2851 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2852 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
2853 }
2854
2855 void InstanceKlass::print_on(outputStream* st) const {
2856 assert(is_klass(), "must be klass");
2857 Klass::print_on(st);
2858
2859 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2860 st->print(BULLET"klass size: %d", size()); st->cr();
2861 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2862 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2863 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2864 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2865 st->print(BULLET"sub: ");
2866 Klass* sub = subklass();
2867 int n;
2868 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2869 if (n < MaxSubklassPrintSize) {
2870 sub->print_value_on(st);
2871 st->print(" ");
2872 }
2873 }
2874 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2875 st->cr();
2876
2877 if (is_interface()) {
2878 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2879 if (nof_implementors() == 1) {
2880 st->print_cr(BULLET"implementor: ");
2881 st->print(" ");
2882 implementor()->print_value_on(st);
2883 st->cr();
2884 }
2885 }
2886
2887 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2888 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2889 if (Verbose || WizardMode) {
2890 Array<Method*>* method_array = methods();
2891 for (int i = 0; i < method_array->length(); i++) {
2892 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2893 }
2894 }
2895 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2896 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2897 if (Verbose && default_methods() != NULL) {
2898 Array<Method*>* method_array = default_methods();
2899 for (int i = 0; i < method_array->length(); i++) {
2900 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2901 }
2902 }
2903 if (default_vtable_indices() != NULL) {
2904 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2905 }
2906 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2907 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2908 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2909 if (class_loader_data() != NULL) {
2910 st->print(BULLET"class loader data: ");
2911 class_loader_data()->print_value_on(st);
2912 st->cr();
2913 }
2914 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2915 if (source_file_name() != NULL) {
2916 st->print(BULLET"source file: ");
2917 source_file_name()->print_value_on(st);
2918 st->cr();
2919 }
2920 if (source_debug_extension() != NULL) {
2921 st->print(BULLET"source debug extension: ");
2922 st->print("%s", source_debug_extension());
2923 st->cr();
2924 }
2925 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2926 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2927 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2928 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2929 {
2930 bool have_pv = false;
2931 // previous versions are linked together through the InstanceKlass
2932 for (InstanceKlass* pv_node = previous_versions();
2933 pv_node != NULL;
2934 pv_node = pv_node->previous_versions()) {
2935 if (!have_pv)
2936 st->print(BULLET"previous version: ");
2937 have_pv = true;
2938 pv_node->constants()->print_value_on(st);
2939 }
2940 if (have_pv) st->cr();
2941 }
2942
2943 if (generic_signature() != NULL) {
2944 st->print(BULLET"generic signature: ");
2945 generic_signature()->print_value_on(st);
2946 st->cr();
2947 }
2948 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2949 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2950 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2951 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2952 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2953 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2954 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2955 FieldPrinter print_static_field(st);
2956 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2957 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2958 FieldPrinter print_nonstatic_field(st);
2959 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2960 ik->do_nonstatic_fields(&print_nonstatic_field);
2961
2962 st->print(BULLET"non-static oop maps: ");
2963 OopMapBlock* map = start_of_nonstatic_oop_maps();
2964 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2965 while (map < end_map) {
2966 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2967 map++;
2968 }
2969 st->cr();
2970 }
2971
2972 #endif //PRODUCT
2973
2974 void InstanceKlass::print_value_on(outputStream* st) const {
2975 assert(is_klass(), "must be klass");
2976 if (Verbose || WizardMode) access_flags().print_on(st);
2977 name()->print_value_on(st);
2978 }
2979
2980 #ifndef PRODUCT
2981
2982 void FieldPrinter::do_field(fieldDescriptor* fd) {
2983 _st->print(BULLET);
2984 if (_obj == NULL) {
2985 fd->print_on(_st);
2986 _st->cr();
2987 } else {
2988 fd->print_on_for(_st, _obj);
2989 _st->cr();
2990 }
2991 }
2992
2993
2994 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2995 Klass::oop_print_on(obj, st);
2996
2997 if (this == SystemDictionary::String_klass()) {
2998 typeArrayOop value = java_lang_String::value(obj);
2999 juint length = java_lang_String::length(obj);
3000 if (value != NULL &&
3001 value->is_typeArray() &&
3002 length <= (juint) value->length()) {
3003 st->print(BULLET"string: ");
3004 java_lang_String::print(obj, st);
3005 st->cr();
3006 if (!WizardMode) return; // that is enough
3007 }
3008 }
3009
3010 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3011 FieldPrinter print_field(st, obj);
3012 do_nonstatic_fields(&print_field);
3013
3014 if (this == SystemDictionary::Class_klass()) {
3015 st->print(BULLET"signature: ");
3016 java_lang_Class::print_signature(obj, st);
3017 st->cr();
3018 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3019 st->print(BULLET"fake entry for mirror: ");
3020 mirrored_klass->print_value_on_maybe_null(st);
3021 st->cr();
3022 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3023 st->print(BULLET"fake entry for array: ");
3024 array_klass->print_value_on_maybe_null(st);
3025 st->cr();
3026 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3027 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3028 Klass* real_klass = java_lang_Class::as_Klass(obj);
3029 if (real_klass != NULL && real_klass->is_instance_klass()) {
3030 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3031 }
3032 } else if (this == SystemDictionary::MethodType_klass()) {
3033 st->print(BULLET"signature: ");
3034 java_lang_invoke_MethodType::print_signature(obj, st);
3035 st->cr();
3036 }
3037 }
3038
3039 #endif //PRODUCT
3040
3041 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3042 st->print("a ");
3043 name()->print_value_on(st);
3044 obj->print_address_on(st);
3045 if (this == SystemDictionary::String_klass()
3046 && java_lang_String::value(obj) != NULL) {
3047 ResourceMark rm;
3048 int len = java_lang_String::length(obj);
3049 int plen = (len < 24 ? len : 12);
3050 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3051 st->print(" = \"%s\"", str);
3052 if (len > plen)
3053 st->print("...[%d]", len);
3054 } else if (this == SystemDictionary::Class_klass()) {
3055 Klass* k = java_lang_Class::as_Klass(obj);
3056 st->print(" = ");
3057 if (k != NULL) {
3058 k->print_value_on(st);
3059 } else {
3060 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3061 st->print("%s", tname ? tname : "type?");
3062 }
3063 } else if (this == SystemDictionary::MethodType_klass()) {
3064 st->print(" = ");
3065 java_lang_invoke_MethodType::print_signature(obj, st);
3066 } else if (java_lang_boxing_object::is_instance(obj)) {
3067 st->print(" = ");
3068 java_lang_boxing_object::print(obj, st);
3069 } else if (this == SystemDictionary::LambdaForm_klass()) {
3070 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3071 if (vmentry != NULL) {
3072 st->print(" => ");
3073 vmentry->print_value_on(st);
3074 }
3075 } else if (this == SystemDictionary::MemberName_klass()) {
3076 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3077 if (vmtarget != NULL) {
3078 st->print(" = ");
3079 vmtarget->print_value_on(st);
3080 } else {
3081 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3082 st->print(".");
3083 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3084 }
3085 }
3086 }
3087
3088 const char* InstanceKlass::internal_name() const {
3089 return external_name();
3090 }
3091
3092 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3093 const char* module_name,
3094 const ClassFileStream* cfs) const {
3095 if (!log_is_enabled(Info, class, load)) {
3096 return;
3097 }
3098
3099 ResourceMark rm;
3100 LogMessage(class, load) msg;
3101 stringStream info_stream;
3102
3103 // Name and class hierarchy info
3104 info_stream.print("%s", external_name());
3105
3106 // Source
3107 if (cfs != NULL) {
3108 if (cfs->source() != NULL) {
3109 if (module_name != NULL) {
3110 if (ClassLoader::is_jrt(cfs->source())) {
3111 info_stream.print(" source: jrt:/%s", module_name);
3112 } else {
3113 info_stream.print(" source: %s", cfs->source());
3114 }
3115 } else {
3116 info_stream.print(" source: %s", cfs->source());
3117 }
3118 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3119 Thread* THREAD = Thread::current();
3120 Klass* caller =
3121 THREAD->is_Java_thread()
3122 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3123 : NULL;
3124 // caller can be NULL, for example, during a JVMTI VM_Init hook
3125 if (caller != NULL) {
3126 info_stream.print(" source: instance of %s", caller->external_name());
3127 } else {
3128 // source is unknown
3129 }
3130 } else {
3131 oop class_loader = loader_data->class_loader();
3132 info_stream.print(" source: %s", class_loader->klass()->external_name());
3133 }
3134 } else {
3135 info_stream.print(" source: shared objects file");
3136 }
3137
3138 msg.info("%s", info_stream.as_string());
3139
3140 if (log_is_enabled(Debug, class, load)) {
3141 stringStream debug_stream;
3142
3143 // Class hierarchy info
3144 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3145 p2i(this), p2i(superklass()));
3146
3147 // Interfaces
3148 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3149 debug_stream.print(" interfaces:");
3150 int length = local_interfaces()->length();
3151 for (int i = 0; i < length; i++) {
3152 debug_stream.print(" " INTPTR_FORMAT,
3153 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3154 }
3155 }
3156
3157 // Class loader
3158 debug_stream.print(" loader: [");
3159 loader_data->print_value_on(&debug_stream);
3160 debug_stream.print("]");
3161
3162 // Classfile checksum
3163 if (cfs) {
3164 debug_stream.print(" bytes: %d checksum: %08x",
3165 cfs->length(),
3166 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3167 cfs->length()));
3168 }
3169
3170 msg.debug("%s", debug_stream.as_string());
3171 }
3172 }
3173
3174 #if INCLUDE_SERVICES
3175 // Size Statistics
3176 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3177 Klass::collect_statistics(sz);
3178
3179 sz->_inst_size = wordSize * size_helper();
3180 sz->_vtab_bytes = wordSize * vtable_length();
3181 sz->_itab_bytes = wordSize * itable_length();
3182 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3183
3184 int n = 0;
3185 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3186 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3187 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3188 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3189 n += (sz->_fields_bytes = sz->count_array(fields()));
3190 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3191 sz->_ro_bytes += n;
3192
3193 const ConstantPool* cp = constants();
3194 if (cp) {
3195 cp->collect_statistics(sz);
3196 }
3197
3198 const Annotations* anno = annotations();
3199 if (anno) {
3200 anno->collect_statistics(sz);
3201 }
3202
3203 const Array<Method*>* methods_array = methods();
3204 if (methods()) {
3205 for (int i = 0; i < methods_array->length(); i++) {
3206 Method* method = methods_array->at(i);
3207 if (method) {
3208 sz->_method_count ++;
3209 method->collect_statistics(sz);
3210 }
3211 }
3212 }
3213 }
3214 #endif // INCLUDE_SERVICES
3215
3216 // Verification
3217
3218 class VerifyFieldClosure: public OopClosure {
3219 protected:
3220 template <class T> void do_oop_work(T* p) {
3221 oop obj = oopDesc::load_decode_heap_oop(p);
3222 if (!oopDesc::is_oop_or_null(obj)) {
3223 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3224 Universe::print_on(tty);
3225 guarantee(false, "boom");
3226 }
3227 }
3228 public:
3229 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3230 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3231 };
3232
3233 void InstanceKlass::verify_on(outputStream* st) {
3234 #ifndef PRODUCT
3235 // Avoid redundant verifies, this really should be in product.
3236 if (_verify_count == Universe::verify_count()) return;
3237 _verify_count = Universe::verify_count();
3238 #endif
3239
3240 // Verify Klass
3241 Klass::verify_on(st);
3242
3243 // Verify that klass is present in ClassLoaderData
3244 guarantee(class_loader_data()->contains_klass(this),
3245 "this class isn't found in class loader data");
3246
3247 // Verify vtables
3248 if (is_linked()) {
3249 // $$$ This used to be done only for m/s collections. Doing it
3250 // always seemed a valid generalization. (DLD -- 6/00)
3251 vtable().verify(st);
3252 }
3253
3254 // Verify first subklass
3255 if (subklass() != NULL) {
3256 guarantee(subklass()->is_klass(), "should be klass");
3257 }
3258
3259 // Verify siblings
3260 Klass* super = this->super();
3261 Klass* sib = next_sibling();
3262 if (sib != NULL) {
3263 if (sib == this) {
3264 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3265 }
3266
3267 guarantee(sib->is_klass(), "should be klass");
3268 guarantee(sib->super() == super, "siblings should have same superklass");
3269 }
3270
3271 // Verify implementor fields
3272 Klass* im = implementor();
3273 if (im != NULL) {
3274 guarantee(is_interface(), "only interfaces should have implementor set");
3275 guarantee(im->is_klass(), "should be klass");
3276 guarantee(!im->is_interface() || im == this,
3277 "implementors cannot be interfaces");
3278 }
3279
3280 // Verify local interfaces
3281 if (local_interfaces()) {
3282 Array<Klass*>* local_interfaces = this->local_interfaces();
3283 for (int j = 0; j < local_interfaces->length(); j++) {
3284 Klass* e = local_interfaces->at(j);
3285 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3286 }
3287 }
3288
3289 // Verify transitive interfaces
3290 if (transitive_interfaces() != NULL) {
3291 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3292 for (int j = 0; j < transitive_interfaces->length(); j++) {
3293 Klass* e = transitive_interfaces->at(j);
3294 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3295 }
3296 }
3297
3298 // Verify methods
3299 if (methods() != NULL) {
3300 Array<Method*>* methods = this->methods();
3301 for (int j = 0; j < methods->length(); j++) {
3302 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3303 }
3304 for (int j = 0; j < methods->length() - 1; j++) {
3305 Method* m1 = methods->at(j);
3306 Method* m2 = methods->at(j + 1);
3307 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3308 }
3309 }
3310
3311 // Verify method ordering
3312 if (method_ordering() != NULL) {
3313 Array<int>* method_ordering = this->method_ordering();
3314 int length = method_ordering->length();
3315 if (JvmtiExport::can_maintain_original_method_order() ||
3316 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3317 guarantee(length == methods()->length(), "invalid method ordering length");
3318 jlong sum = 0;
3319 for (int j = 0; j < length; j++) {
3320 int original_index = method_ordering->at(j);
3321 guarantee(original_index >= 0, "invalid method ordering index");
3322 guarantee(original_index < length, "invalid method ordering index");
3323 sum += original_index;
3324 }
3325 // Verify sum of indices 0,1,...,length-1
3326 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3327 } else {
3328 guarantee(length == 0, "invalid method ordering length");
3329 }
3330 }
3331
3332 // Verify default methods
3333 if (default_methods() != NULL) {
3334 Array<Method*>* methods = this->default_methods();
3335 for (int j = 0; j < methods->length(); j++) {
3336 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3337 }
3338 for (int j = 0; j < methods->length() - 1; j++) {
3339 Method* m1 = methods->at(j);
3340 Method* m2 = methods->at(j + 1);
3341 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3342 }
3343 }
3344
3345 // Verify JNI static field identifiers
3346 if (jni_ids() != NULL) {
3347 jni_ids()->verify(this);
3348 }
3349
3350 // Verify other fields
3351 if (array_klasses() != NULL) {
3352 guarantee(array_klasses()->is_klass(), "should be klass");
3353 }
3354 if (constants() != NULL) {
3355 guarantee(constants()->is_constantPool(), "should be constant pool");
3356 }
3357 const Klass* host = host_klass();
3358 if (host != NULL) {
3359 guarantee(host->is_klass(), "should be klass");
3360 }
3361 }
3362
3363 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3364 Klass::oop_verify_on(obj, st);
3365 VerifyFieldClosure blk;
3366 obj->oop_iterate_no_header(&blk);
3367 }
3368
3369
3370 // JNIid class for jfieldIDs only
3371 // Note to reviewers:
3372 // These JNI functions are just moved over to column 1 and not changed
3373 // in the compressed oops workspace.
3374 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3375 _holder = holder;
3376 _offset = offset;
3377 _next = next;
3378 debug_only(_is_static_field_id = false;)
3379 }
3380
3381
3382 JNIid* JNIid::find(int offset) {
3383 JNIid* current = this;
3384 while (current != NULL) {
3385 if (current->offset() == offset) return current;
3386 current = current->next();
3387 }
3388 return NULL;
3389 }
3390
3391 void JNIid::deallocate(JNIid* current) {
3392 while (current != NULL) {
3393 JNIid* next = current->next();
3394 delete current;
3395 current = next;
3396 }
3397 }
3398
3399
3400 void JNIid::verify(Klass* holder) {
3401 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3402 int end_field_offset;
3403 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3404
3405 JNIid* current = this;
3406 while (current != NULL) {
3407 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3408 #ifdef ASSERT
3409 int o = current->offset();
3410 if (current->is_static_field_id()) {
3411 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3412 }
3413 #endif
3414 current = current->next();
3415 }
3416 }
3417
3418
3419 #ifdef ASSERT
3420 void InstanceKlass::set_init_state(ClassState state) {
3421 bool good_state = is_shared() ? (_init_state <= state)
3422 : (_init_state < state);
3423 assert(good_state || state == allocated, "illegal state transition");
3424 _init_state = (u1)state;
3425 }
3426 #endif
3427
3428 #if INCLUDE_JVMTI
3429
3430 // RedefineClasses() support for previous versions
3431
3432 // Globally, there is at least one previous version of a class to walk
3433 // during class unloading, which is saved because old methods in the class
3434 // are still running. Otherwise the previous version list is cleaned up.
3435 bool InstanceKlass::_has_previous_versions = false;
3436
3437 // Returns true if there are previous versions of a class for class
3438 // unloading only. Also resets the flag to false. purge_previous_version
3439 // will set the flag to true if there are any left, i.e., if there's any
3440 // work to do for next time. This is to avoid the expensive code cache
3441 // walk in CLDG::do_unloading().
3442 bool InstanceKlass::has_previous_versions_and_reset() {
3443 bool ret = _has_previous_versions;
3444 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3445 ret ? "true" : "false");
3446 _has_previous_versions = false;
3447 return ret;
3448 }
3449
3450 // Purge previous versions before adding new previous versions of the class and
3451 // during class unloading.
3452 void InstanceKlass::purge_previous_version_list() {
3453 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3454 assert(has_been_redefined(), "Should only be called for main class");
3455
3456 // Quick exit.
3457 if (previous_versions() == NULL) {
3458 return;
3459 }
3460
3461 // This klass has previous versions so see what we can cleanup
3462 // while it is safe to do so.
3463
3464 int deleted_count = 0; // leave debugging breadcrumbs
3465 int live_count = 0;
3466 ClassLoaderData* loader_data = class_loader_data();
3467 assert(loader_data != NULL, "should never be null");
3468
3469 ResourceMark rm;
3470 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3471
3472 // previous versions are linked together through the InstanceKlass
3473 InstanceKlass* pv_node = previous_versions();
3474 InstanceKlass* last = this;
3475 int version = 0;
3476
3477 // check the previous versions list
3478 for (; pv_node != NULL; ) {
3479
3480 ConstantPool* pvcp = pv_node->constants();
3481 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3482
3483 if (!pvcp->on_stack()) {
3484 // If the constant pool isn't on stack, none of the methods
3485 // are executing. Unlink this previous_version.
3486 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3487 // so will be deallocated during the next phase of class unloading.
3488 log_trace(redefine, class, iklass, purge)
3489 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3490 // For debugging purposes.
3491 pv_node->set_is_scratch_class();
3492 // Unlink from previous version list.
3493 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3494 InstanceKlass* next = pv_node->previous_versions();
3495 pv_node->link_previous_versions(NULL); // point next to NULL
3496 last->link_previous_versions(next);
3497 // Add to the deallocate list after unlinking
3498 loader_data->add_to_deallocate_list(pv_node);
3499 pv_node = next;
3500 deleted_count++;
3501 version++;
3502 continue;
3503 } else {
3504 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3505 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3506 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3507 live_count++;
3508 // found a previous version for next time we do class unloading
3509 _has_previous_versions = true;
3510 }
3511
3512 // At least one method is live in this previous version.
3513 // Reset dead EMCP methods not to get breakpoints.
3514 // All methods are deallocated when all of the methods for this class are no
3515 // longer running.
3516 Array<Method*>* method_refs = pv_node->methods();
3517 if (method_refs != NULL) {
3518 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3519 for (int j = 0; j < method_refs->length(); j++) {
3520 Method* method = method_refs->at(j);
3521
3522 if (!method->on_stack()) {
3523 // no breakpoints for non-running methods
3524 if (method->is_running_emcp()) {
3525 method->set_running_emcp(false);
3526 }
3527 } else {
3528 assert (method->is_obsolete() || method->is_running_emcp(),
3529 "emcp method cannot run after emcp bit is cleared");
3530 log_trace(redefine, class, iklass, purge)
3531 ("purge: %s(%s): prev method @%d in version @%d is alive",
3532 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3533 }
3534 }
3535 }
3536 // next previous version
3537 last = pv_node;
3538 pv_node = pv_node->previous_versions();
3539 version++;
3540 }
3541 log_trace(redefine, class, iklass, purge)
3542 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3543 }
3544
3545 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3546 int emcp_method_count) {
3547 int obsolete_method_count = old_methods->length() - emcp_method_count;
3548
3549 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3550 _previous_versions != NULL) {
3551 // We have a mix of obsolete and EMCP methods so we have to
3552 // clear out any matching EMCP method entries the hard way.
3553 int local_count = 0;
3554 for (int i = 0; i < old_methods->length(); i++) {
3555 Method* old_method = old_methods->at(i);
3556 if (old_method->is_obsolete()) {
3557 // only obsolete methods are interesting
3558 Symbol* m_name = old_method->name();
3559 Symbol* m_signature = old_method->signature();
3560
3561 // previous versions are linked together through the InstanceKlass
3562 int j = 0;
3563 for (InstanceKlass* prev_version = _previous_versions;
3564 prev_version != NULL;
3565 prev_version = prev_version->previous_versions(), j++) {
3566
3567 Array<Method*>* method_refs = prev_version->methods();
3568 for (int k = 0; k < method_refs->length(); k++) {
3569 Method* method = method_refs->at(k);
3570
3571 if (!method->is_obsolete() &&
3572 method->name() == m_name &&
3573 method->signature() == m_signature) {
3574 // The current RedefineClasses() call has made all EMCP
3575 // versions of this method obsolete so mark it as obsolete
3576 log_trace(redefine, class, iklass, add)
3577 ("%s(%s): flush obsolete method @%d in version @%d",
3578 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3579
3580 method->set_is_obsolete();
3581 break;
3582 }
3583 }
3584
3585 // The previous loop may not find a matching EMCP method, but
3586 // that doesn't mean that we can optimize and not go any
3587 // further back in the PreviousVersion generations. The EMCP
3588 // method for this generation could have already been made obsolete,
3589 // but there still may be an older EMCP method that has not
3590 // been made obsolete.
3591 }
3592
3593 if (++local_count >= obsolete_method_count) {
3594 // no more obsolete methods so bail out now
3595 break;
3596 }
3597 }
3598 }
3599 }
3600 }
3601
3602 // Save the scratch_class as the previous version if any of the methods are running.
3603 // The previous_versions are used to set breakpoints in EMCP methods and they are
3604 // also used to clean MethodData links to redefined methods that are no longer running.
3605 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3606 int emcp_method_count) {
3607 assert(Thread::current()->is_VM_thread(),
3608 "only VMThread can add previous versions");
3609
3610 ResourceMark rm;
3611 log_trace(redefine, class, iklass, add)
3612 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3613
3614 // Clean out old previous versions for this class
3615 purge_previous_version_list();
3616
3617 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3618 // a previous redefinition may be made obsolete by this redefinition.
3619 Array<Method*>* old_methods = scratch_class->methods();
3620 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3621
3622 // If the constant pool for this previous version of the class
3623 // is not marked as being on the stack, then none of the methods
3624 // in this previous version of the class are on the stack so
3625 // we don't need to add this as a previous version.
3626 ConstantPool* cp_ref = scratch_class->constants();
3627 if (!cp_ref->on_stack()) {
3628 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3629 // For debugging purposes.
3630 scratch_class->set_is_scratch_class();
3631 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3632 return;
3633 }
3634
3635 if (emcp_method_count != 0) {
3636 // At least one method is still running, check for EMCP methods
3637 for (int i = 0; i < old_methods->length(); i++) {
3638 Method* old_method = old_methods->at(i);
3639 if (!old_method->is_obsolete() && old_method->on_stack()) {
3640 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3641 // we can add breakpoints for it.
3642
3643 // We set the method->on_stack bit during safepoints for class redefinition
3644 // and use this bit to set the is_running_emcp bit.
3645 // After the safepoint, the on_stack bit is cleared and the running emcp
3646 // method may exit. If so, we would set a breakpoint in a method that
3647 // is never reached, but this won't be noticeable to the programmer.
3648 old_method->set_running_emcp(true);
3649 log_trace(redefine, class, iklass, add)
3650 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3651 } else if (!old_method->is_obsolete()) {
3652 log_trace(redefine, class, iklass, add)
3653 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3654 }
3655 }
3656 }
3657
3658 // Add previous version if any methods are still running.
3659 // Set has_previous_version flag for processing during class unloading.
3660 _has_previous_versions = true;
3661 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3662 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3663 scratch_class->link_previous_versions(previous_versions());
3664 link_previous_versions(scratch_class);
3665 } // end add_previous_version()
3666
3667 #endif // INCLUDE_JVMTI
3668
3669 Method* InstanceKlass::method_with_idnum(int idnum) {
3670 Method* m = NULL;
3671 if (idnum < methods()->length()) {
3672 m = methods()->at(idnum);
3673 }
3674 if (m == NULL || m->method_idnum() != idnum) {
3675 for (int index = 0; index < methods()->length(); ++index) {
3676 m = methods()->at(index);
3677 if (m->method_idnum() == idnum) {
3678 return m;
3679 }
3680 }
3681 // None found, return null for the caller to handle.
3682 return NULL;
3683 }
3684 return m;
3685 }
3686
3687
3688 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3689 if (idnum >= methods()->length()) {
3690 return NULL;
3691 }
3692 Method* m = methods()->at(idnum);
3693 if (m != NULL && m->orig_method_idnum() == idnum) {
3694 return m;
3695 }
3696 // Obsolete method idnum does not match the original idnum
3697 for (int index = 0; index < methods()->length(); ++index) {
3698 m = methods()->at(index);
3699 if (m->orig_method_idnum() == idnum) {
3700 return m;
3701 }
3702 }
3703 // None found, return null for the caller to handle.
3704 return NULL;
3705 }
3706
3707
3708 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3709 InstanceKlass* holder = get_klass_version(version);
3710 if (holder == NULL) {
3711 return NULL; // The version of klass is gone, no method is found
3712 }
3713 Method* method = holder->method_with_orig_idnum(idnum);
3714 return method;
3715 }
3716
3717 #if INCLUDE_JVMTI
3718 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3719 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3720 // Ignore the archived class stream data
3721 return NULL;
3722 } else {
3723 return _cached_class_file;
3724 }
3725 }
3726
3727 jint InstanceKlass::get_cached_class_file_len() {
3728 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3729 }
3730
3731 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3732 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3733 }
3734
3735 #if INCLUDE_CDS
3736 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3737 if (DumpSharedSpaces) {
3738 return _cached_class_file;
3739 } else {
3740 assert(this->is_shared(), "class should be shared");
3741 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3742 return _cached_class_file;
3743 } else {
3744 return NULL;
3745 }
3746 }
3747 }
3748 #endif
3749 #endif