1 /*
2 * Copyright (c) 1997, 2018, 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 "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/verifier.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/dependencyContext.hpp"
39 #include "compiler/compileBroker.hpp"
40 #include "gc/shared/collectedHeap.inline.hpp"
41 #include "gc/shared/specialized_oop_closures.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "interpreter/rewriter.hpp"
44 #include "jvmtifiles/jvmti.h"
45 #include "logging/log.hpp"
46 #include "logging/logMessage.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.hpp"
49 #include "memory/heapInspection.hpp"
50 #include "memory/iterator.inline.hpp"
51 #include "memory/metadataFactory.hpp"
52 #include "memory/metaspaceClosure.hpp"
53 #include "memory/metaspaceShared.hpp"
54 #include "memory/oopFactory.hpp"
55 #include "memory/resourceArea.hpp"
56 #include "oops/fieldStreams.hpp"
57 #include "oops/instanceClassLoaderKlass.hpp"
58 #include "oops/instanceKlass.inline.hpp"
59 #include "oops/instanceMirrorKlass.hpp"
60 #include "oops/instanceOop.hpp"
61 #include "oops/klass.inline.hpp"
62 #include "oops/method.hpp"
63 #include "oops/oop.inline.hpp"
64 #include "oops/symbol.hpp"
65 #include "prims/jvmtiExport.hpp"
66 #include "prims/jvmtiRedefineClasses.hpp"
67 #include "prims/jvmtiThreadState.hpp"
68 #include "prims/methodComparator.hpp"
69 #include "runtime/atomic.hpp"
70 #include "runtime/fieldDescriptor.hpp"
71 #include "runtime/handles.inline.hpp"
72 #include "runtime/javaCalls.hpp"
73 #include "runtime/mutexLocker.hpp"
74 #include "runtime/orderAccess.inline.hpp"
75 #include "runtime/thread.inline.hpp"
76 #include "services/classLoadingService.hpp"
77 #include "services/threadService.hpp"
78 #include "utilities/dtrace.hpp"
79 #include "utilities/macros.hpp"
80 #include "utilities/stringUtils.hpp"
81 #ifdef COMPILER1
82 #include "c1/c1_Compiler.hpp"
83 #endif
84
85 #ifdef DTRACE_ENABLED
86
87
88 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
89 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
90 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
91 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
92 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
93 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
94 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
95 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
96 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
97 { \
98 char* data = NULL; \
99 int len = 0; \
100 Symbol* clss_name = name(); \
101 if (clss_name != NULL) { \
102 data = (char*)clss_name->bytes(); \
103 len = clss_name->utf8_length(); \
104 } \
105 HOTSPOT_CLASS_INITIALIZATION_##type( \
106 data, len, (void*)class_loader(), thread_type); \
107 }
108
109 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
110 { \
111 char* data = NULL; \
112 int len = 0; \
113 Symbol* clss_name = name(); \
114 if (clss_name != NULL) { \
115 data = (char*)clss_name->bytes(); \
116 len = clss_name->utf8_length(); \
117 } \
118 HOTSPOT_CLASS_INITIALIZATION_##type( \
119 data, len, (void*)class_loader(), thread_type, wait); \
120 }
121
122 #else // ndef DTRACE_ENABLED
123
124 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
125 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
126
127 #endif // ndef DTRACE_ENABLED
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(parser.is_anonymous()));
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 return ik;
190 }
191
192
193 // copy method ordering from resource area to Metaspace
194 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
195 if (m != NULL) {
196 // allocate a new array and copy contents (memcpy?)
197 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
198 for (int i = 0; i < m->length(); i++) {
199 _method_ordering->at_put(i, m->at(i));
200 }
201 } else {
202 _method_ordering = Universe::the_empty_int_array();
203 }
204 }
205
206 // create a new array of vtable_indices for default methods
207 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
208 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
209 assert(default_vtable_indices() == NULL, "only create once");
210 set_default_vtable_indices(vtable_indices);
211 return vtable_indices;
212 }
213
214 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
215 _static_field_size(parser.static_field_size()),
216 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
217 _itable_len(parser.itable_size()),
218 _reference_type(parser.reference_type()) {
219 set_vtable_length(parser.vtable_size());
220 set_kind(kind);
221 set_access_flags(parser.access_flags());
222 set_is_anonymous(parser.is_anonymous());
223 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
224 false));
225
226 assert(NULL == _methods, "underlying memory not zeroed?");
227 assert(is_instance_klass(), "is layout incorrect?");
228 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
229 }
230
231 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
232 Array<Method*>* methods) {
233 if (methods != NULL && methods != Universe::the_empty_method_array() &&
234 !methods->is_shared()) {
235 for (int i = 0; i < methods->length(); i++) {
236 Method* method = methods->at(i);
237 if (method == NULL) continue; // maybe null if error processing
238 // Only want to delete methods that are not executing for RedefineClasses.
239 // The previous version will point to them so they're not totally dangling
240 assert (!method->on_stack(), "shouldn't be called with methods on stack");
241 MetadataFactory::free_metadata(loader_data, method);
242 }
243 MetadataFactory::free_array<Method*>(loader_data, methods);
244 }
245 }
246
247 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
248 const Klass* super_klass,
249 Array<Klass*>* local_interfaces,
250 Array<Klass*>* transitive_interfaces) {
251 // Only deallocate transitive interfaces if not empty, same as super class
252 // or same as local interfaces. See code in parseClassFile.
253 Array<Klass*>* ti = transitive_interfaces;
254 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
255 // check that the interfaces don't come from super class
256 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
257 InstanceKlass::cast(super_klass)->transitive_interfaces();
258 if (ti != sti && ti != NULL && !ti->is_shared()) {
259 MetadataFactory::free_array<Klass*>(loader_data, ti);
260 }
261 }
262
263 // local interfaces can be empty
264 if (local_interfaces != Universe::the_empty_klass_array() &&
265 local_interfaces != NULL && !local_interfaces->is_shared()) {
266 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
267 }
268 }
269
270 // This function deallocates the metadata and C heap pointers that the
271 // InstanceKlass points to.
272 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
273
274 // Orphan the mirror first, CMS thinks it's still live.
275 if (java_mirror() != NULL) {
276 java_lang_Class::set_klass(java_mirror(), NULL);
277 }
278
279 // Also remove mirror from handles
280 loader_data->remove_handle(_java_mirror);
281
282 // Need to take this class off the class loader data list.
283 loader_data->remove_class(this);
284
285 // The array_klass for this class is created later, after error handling.
286 // For class redefinition, we keep the original class so this scratch class
287 // doesn't have an array class. Either way, assert that there is nothing
288 // to deallocate.
289 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
290
291 // Release C heap allocated data that this might point to, which includes
292 // reference counting symbol names.
293 release_C_heap_structures();
294
295 deallocate_methods(loader_data, methods());
296 set_methods(NULL);
297
298 if (method_ordering() != NULL &&
299 method_ordering() != Universe::the_empty_int_array() &&
300 !method_ordering()->is_shared()) {
301 MetadataFactory::free_array<int>(loader_data, method_ordering());
302 }
303 set_method_ordering(NULL);
304
305 // default methods can be empty
306 if (default_methods() != NULL &&
307 default_methods() != Universe::the_empty_method_array() &&
308 !default_methods()->is_shared()) {
309 MetadataFactory::free_array<Method*>(loader_data, default_methods());
310 }
311 // Do NOT deallocate the default methods, they are owned by superinterfaces.
312 set_default_methods(NULL);
313
314 // default methods vtable indices can be empty
315 if (default_vtable_indices() != NULL &&
316 !default_vtable_indices()->is_shared()) {
317 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
318 }
319 set_default_vtable_indices(NULL);
320
321
322 // This array is in Klass, but remove it with the InstanceKlass since
323 // this place would be the only caller and it can share memory with transitive
324 // interfaces.
325 if (secondary_supers() != NULL &&
326 secondary_supers() != Universe::the_empty_klass_array() &&
327 secondary_supers() != transitive_interfaces() &&
328 !secondary_supers()->is_shared()) {
329 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
330 }
331 set_secondary_supers(NULL);
332
333 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
334 set_transitive_interfaces(NULL);
335 set_local_interfaces(NULL);
336
337 if (fields() != NULL && !fields()->is_shared()) {
338 MetadataFactory::free_array<jushort>(loader_data, fields());
339 }
340 set_fields(NULL, 0);
341
342 // If a method from a redefined class is using this constant pool, don't
343 // delete it, yet. The new class's previous version will point to this.
344 if (constants() != NULL) {
345 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
346 if (!constants()->is_shared()) {
347 MetadataFactory::free_metadata(loader_data, constants());
348 }
349 // Delete any cached resolution errors for the constant pool
350 SystemDictionary::delete_resolution_error(constants());
351
352 set_constants(NULL);
353 }
354
355 if (inner_classes() != NULL &&
356 inner_classes() != Universe::the_empty_short_array() &&
357 !inner_classes()->is_shared()) {
358 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
359 }
360 set_inner_classes(NULL);
361
362 // We should deallocate the Annotations instance if it's not in shared spaces.
363 if (annotations() != NULL && !annotations()->is_shared()) {
364 MetadataFactory::free_metadata(loader_data, annotations());
365 }
366 set_annotations(NULL);
367 }
368
369 bool InstanceKlass::should_be_initialized() const {
370 return !is_initialized();
371 }
372
373 klassItable InstanceKlass::itable() const {
374 return klassItable(const_cast<InstanceKlass*>(this));
375 }
376
377 void InstanceKlass::eager_initialize(Thread *thread) {
378 if (!EagerInitialization) return;
379
380 if (this->is_not_initialized()) {
381 // abort if the the class has a class initializer
382 if (this->class_initializer() != NULL) return;
383
384 // abort if it is java.lang.Object (initialization is handled in genesis)
385 Klass* super_klass = super();
386 if (super_klass == NULL) return;
387
388 // abort if the super class should be initialized
389 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
390
391 // call body to expose the this pointer
392 eager_initialize_impl();
393 }
394 }
395
396 // JVMTI spec thinks there are signers and protection domain in the
397 // instanceKlass. These accessors pretend these fields are there.
398 // The hprof specification also thinks these fields are in InstanceKlass.
399 oop InstanceKlass::protection_domain() const {
400 // return the protection_domain from the mirror
401 return java_lang_Class::protection_domain(java_mirror());
402 }
403
404 // To remove these from requires an incompatible change and CCC request.
405 objArrayOop InstanceKlass::signers() const {
406 // return the signers from the mirror
407 return java_lang_Class::signers(java_mirror());
408 }
409
410 oop InstanceKlass::init_lock() const {
411 // return the init lock from the mirror
412 oop lock = java_lang_Class::init_lock(java_mirror());
413 // Prevent reordering with any access of initialization state
414 OrderAccess::loadload();
415 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
416 "only fully initialized state can have a null lock");
417 return lock;
418 }
419
420 // Set the initialization lock to null so the object can be GC'ed. Any racing
421 // threads to get this lock will see a null lock and will not lock.
422 // That's okay because they all check for initialized state after getting
423 // the lock and return.
424 void InstanceKlass::fence_and_clear_init_lock() {
425 // make sure previous stores are all done, notably the init_state.
426 OrderAccess::storestore();
427 java_lang_Class::set_init_lock(java_mirror(), NULL);
428 assert(!is_not_initialized(), "class must be initialized now");
429 }
430
431 void InstanceKlass::eager_initialize_impl() {
432 EXCEPTION_MARK;
433 HandleMark hm(THREAD);
434 Handle h_init_lock(THREAD, init_lock());
435 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
436
437 // abort if someone beat us to the initialization
438 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
439
440 ClassState old_state = init_state();
441 link_class_impl(true, THREAD);
442 if (HAS_PENDING_EXCEPTION) {
443 CLEAR_PENDING_EXCEPTION;
444 // Abort if linking the class throws an exception.
445
446 // Use a test to avoid redundantly resetting the state if there's
447 // no change. Set_init_state() asserts that state changes make
448 // progress, whereas here we might just be spinning in place.
449 if (old_state != _init_state)
450 set_init_state(old_state);
451 } else {
452 // linking successfull, mark class as initialized
453 set_init_state(fully_initialized);
454 fence_and_clear_init_lock();
455 // trace
456 if (log_is_enabled(Info, class, init)) {
457 ResourceMark rm(THREAD);
458 log_info(class, init)("[Initialized %s without side effects]", external_name());
459 }
460 }
461 }
462
463
464 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
465 // process. The step comments refers to the procedure described in that section.
466 // Note: implementation moved to static method to expose the this pointer.
467 void InstanceKlass::initialize(TRAPS) {
468 if (this->should_be_initialized()) {
469 initialize_impl(CHECK);
470 // Note: at this point the class may be initialized
471 // OR it may be in the state of being initialized
472 // in case of recursive initialization!
473 } else {
474 assert(is_initialized(), "sanity check");
475 }
476 }
477
478
479 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
480 // 1) Verify the bytecodes
481 Verifier::Mode mode =
482 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
483 return Verifier::verify(this, mode, should_verify_class(), THREAD);
484 }
485
486
487 // Used exclusively by the shared spaces dump mechanism to prevent
488 // classes mapped into the shared regions in new VMs from appearing linked.
489
490 void InstanceKlass::unlink_class() {
491 assert(is_linked(), "must be linked");
492 _init_state = loaded;
493 }
494
495 void InstanceKlass::link_class(TRAPS) {
496 assert(is_loaded(), "must be loaded");
497 if (!is_linked()) {
498 link_class_impl(true, CHECK);
499 }
500 }
501
502 // Called to verify that a class can link during initialization, without
503 // throwing a VerifyError.
504 bool InstanceKlass::link_class_or_fail(TRAPS) {
505 assert(is_loaded(), "must be loaded");
506 if (!is_linked()) {
507 link_class_impl(false, CHECK_false);
508 }
509 return is_linked();
510 }
511
512 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
513 if (DumpSharedSpaces && is_in_error_state()) {
514 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
515 // the class has failed verification. Throwing the NoClassDefFoundError here is just
516 // a convenient way to stop repeated attempts to verify the same (bad) class.
517 //
518 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
519 // if we are executing Java code. This is not a problem for CDS dumping phase since
520 // it doesn't execute any Java code.
521 ResourceMark rm(THREAD);
522 stringStream ss;
523 ss.print("%s: cannot link class because prior initialization attempt failed",
524 class_loader_and_module_name());
525 // Chain the exception that originally caused clinit to fail.
526 Exceptions::_throw_msg_cause(THREAD_AND_LOCATION,
527 vmSymbols::java_lang_NoClassDefFoundError(),
528 ss.as_string(),
529 Handle(THREAD, java_lang_Class::exceptionThrownDuringClinit(java_mirror())));
530 return false;
531 }
532 // return if already verified
533 if (is_linked()) {
534 return true;
535 }
536
537 // Timing
538 // timer handles recursion
539 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
540 JavaThread* jt = (JavaThread*)THREAD;
541
542 // link super class before linking this class
543 Klass* super_klass = super();
544 if (super_klass != NULL) {
545 if (super_klass->is_interface()) { // check if super class is an interface
546 ResourceMark rm(THREAD);
547 Exceptions::fthrow(
548 THREAD_AND_LOCATION,
549 vmSymbols::java_lang_IncompatibleClassChangeError(),
550 "class %s has interface %s as super class",
551 external_name(),
552 super_klass->external_name()
553 );
554 return false;
555 }
556
557 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
558 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
559 }
560
561 // link all interfaces implemented by this class before linking this class
562 Array<Klass*>* interfaces = local_interfaces();
563 int num_interfaces = interfaces->length();
564 for (int index = 0; index < num_interfaces; index++) {
565 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
566 interk->link_class_impl(throw_verifyerror, CHECK_false);
567 }
568
569 // in case the class is linked in the process of linking its superclasses
570 if (is_linked()) {
571 return true;
572 }
573
574 // trace only the link time for this klass that includes
575 // the verification time
576 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
577 ClassLoader::perf_class_link_selftime(),
578 ClassLoader::perf_classes_linked(),
579 jt->get_thread_stat()->perf_recursion_counts_addr(),
580 jt->get_thread_stat()->perf_timers_addr(),
581 PerfClassTraceTime::CLASS_LINK);
582
583 // verification & rewriting
584 {
585 HandleMark hm(THREAD);
586 Handle h_init_lock(THREAD, init_lock());
587 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
588 // rewritten will have been set if loader constraint error found
589 // on an earlier link attempt
590 // don't verify or rewrite if already rewritten
591 //
592
593 if (!is_linked()) {
594 if (!is_rewritten()) {
595 {
596 bool verify_ok = verify_code(throw_verifyerror, THREAD);
597 if (!verify_ok) {
598 return false;
599 }
600 }
601
602 // Just in case a side-effect of verify linked this class already
603 // (which can sometimes happen since the verifier loads classes
604 // using custom class loaders, which are free to initialize things)
605 if (is_linked()) {
606 return true;
607 }
608
609 // also sets rewritten
610 rewrite_class(CHECK_false);
611 } else if (is_shared()) {
612 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
613 }
614
615 // relocate jsrs and link methods after they are all rewritten
616 link_methods(CHECK_false);
617
618 // Initialize the vtable and interface table after
619 // methods have been rewritten since rewrite may
620 // fabricate new Method*s.
621 // also does loader constraint checking
622 //
623 // initialize_vtable and initialize_itable need to be rerun for
624 // a shared class if the class is not loaded by the NULL classloader.
625 ClassLoaderData * loader_data = class_loader_data();
626 if (!(is_shared() &&
627 loader_data->is_the_null_class_loader_data())) {
628 ResourceMark rm(THREAD);
629 vtable().initialize_vtable(true, CHECK_false);
630 itable().initialize_itable(true, CHECK_false);
631 }
632 #ifdef ASSERT
633 else {
634 vtable().verify(tty, true);
635 // In case itable verification is ever added.
636 // itable().verify(tty, true);
637 }
638 #endif
639 set_init_state(linked);
640 if (JvmtiExport::should_post_class_prepare()) {
641 Thread *thread = THREAD;
642 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
643 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
644 }
645 }
646 }
647 return true;
648 }
649
650
651 // Rewrite the byte codes of all of the methods of a class.
652 // The rewriter must be called exactly once. Rewriting must happen after
653 // verification but before the first method of the class is executed.
654 void InstanceKlass::rewrite_class(TRAPS) {
655 assert(is_loaded(), "must be loaded");
656 if (is_rewritten()) {
657 assert(is_shared(), "rewriting an unshared class?");
658 return;
659 }
660 Rewriter::rewrite(this, CHECK);
661 set_rewritten();
662 }
663
664 // Now relocate and link method entry points after class is rewritten.
665 // This is outside is_rewritten flag. In case of an exception, it can be
666 // executed more than once.
667 void InstanceKlass::link_methods(TRAPS) {
668 int len = methods()->length();
669 for (int i = len-1; i >= 0; i--) {
670 methodHandle m(THREAD, methods()->at(i));
671
672 // Set up method entry points for compiler and interpreter .
673 m->link_method(m, CHECK);
674 }
675 }
676
677 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
678 void InstanceKlass::initialize_super_interfaces(TRAPS) {
679 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
680 for (int i = 0; i < local_interfaces()->length(); ++i) {
681 Klass* iface = local_interfaces()->at(i);
682 InstanceKlass* ik = InstanceKlass::cast(iface);
683
684 // Initialization is depth first search ie. we start with top of the inheritance tree
685 // has_nonstatic_concrete_methods drives searching superinterfaces since it
686 // means has_nonstatic_concrete_methods in its superinterface hierarchy
687 if (ik->has_nonstatic_concrete_methods()) {
688 ik->initialize_super_interfaces(CHECK);
689 }
690
691 // Only initialize() interfaces that "declare" concrete methods.
692 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
693 ik->initialize(CHECK);
694 }
695 }
696 }
697
698 // Store exception h_exception thrown during clinit to the corresponding field of the
699 // class that could not be initialized by calling the appropriate java method.
700 static void set_exception_thrown_during_clinit(Handle h_mirror, Handle h_exception, TRAPS) {
701 JavaValue result(T_VOID);
702 JavaCalls::call_virtual(&result, h_mirror, h_mirror->klass(),
703 vmSymbols::setExceptionThrownDuringClinit_name(),
704 vmSymbols::throwable_void_signature(), h_exception, CHECK);
705 }
706
707 void InstanceKlass::initialize_impl(TRAPS) {
708 HandleMark hm(THREAD);
709
710 // Make sure klass is linked (verified) before initialization
711 // A class could already be verified, since it has been reflected upon.
712 link_class(CHECK);
713
714 DTRACE_CLASSINIT_PROBE(required, -1);
715
716 bool wait = false;
717
718 // refer to the JVM book page 47 for description of steps
719 // Step 1
720 {
721 Handle h_init_lock(THREAD, init_lock());
722 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
723
724 Thread *self = THREAD; // it's passed the current thread
725
726 // Step 2
727 // If we were to use wait() instead of waitInterruptibly() then
728 // we might end up throwing IE from link/symbol resolution sites
729 // that aren't expected to throw. This would wreak havoc. See 6320309.
730 while(is_being_initialized() && !is_reentrant_initialization(self)) {
731 wait = true;
732 ol.waitUninterruptibly(CHECK);
733 }
734
735 // Step 3
736 if (is_being_initialized() && is_reentrant_initialization(self)) {
737 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
738 return;
739 }
740
741 // Step 4
742 if (is_initialized()) {
743 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
744 return;
745 }
746
747 // Step 5
748 if (is_in_error_state()) {
749 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
750 ResourceMark rm(THREAD);
751 stringStream ss;
752 ss.print("%s: cannot initialize class because prior initialization attempt failed",
753 class_loader_and_module_name());
754 // Chain the exception that originally caused clinit to fail.
755 Exceptions::_throw_msg_cause(THREAD_AND_LOCATION,
756 vmSymbols::java_lang_NoClassDefFoundError(),
757 ss.as_string(),
758 Handle(THREAD, java_lang_Class::exceptionThrownDuringClinit(java_mirror())));
759 return;
760 }
761
762 // Step 6
763 set_init_state(being_initialized);
764 set_init_thread(self);
765 }
766
767 // Step 7
768 // Next, if C is a class rather than an interface, initialize it's super class and super
769 // interfaces.
770 if (!is_interface()) {
771 Klass* super_klass = super();
772 if (super_klass != NULL && super_klass->should_be_initialized()) {
773 super_klass->initialize(THREAD);
774 }
775 // If C implements any interface that declares a non-static, concrete method,
776 // the initialization of C triggers initialization of its super interfaces.
777 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
778 // having a superinterface that declares, non-static, concrete methods
779 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
780 initialize_super_interfaces(THREAD);
781 }
782
783 // If any exceptions, complete abruptly, throwing the same exception as above.
784 if (HAS_PENDING_EXCEPTION) {
785 Handle e(THREAD, PENDING_EXCEPTION);
786 CLEAR_PENDING_EXCEPTION;
787 {
788 EXCEPTION_MARK;
789 // Store the exception that originally caused clinit to fail so it can be
790 // chained in later NoClassDefFoundErrors.
791 set_exception_thrown_during_clinit(Handle(THREAD, java_mirror()), e, THREAD);
792 // Locks object, set state, and notify all waiting threads
793 set_initialization_state_and_notify(initialization_error, THREAD);
794 CLEAR_PENDING_EXCEPTION;
795 }
796 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
797 THROW_OOP(e());
798 }
799 }
800
801 // Look for aot compiled methods for this klass, including class initializer.
802 AOTLoader::load_for_klass(this, THREAD);
803
804 // Step 8
805 {
806 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
807 JavaThread* jt = (JavaThread*)THREAD;
808 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
809 // Timer includes any side effects of class initialization (resolution,
810 // etc), but not recursive entry into call_class_initializer().
811 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
812 ClassLoader::perf_class_init_selftime(),
813 ClassLoader::perf_classes_inited(),
814 jt->get_thread_stat()->perf_recursion_counts_addr(),
815 jt->get_thread_stat()->perf_timers_addr(),
816 PerfClassTraceTime::CLASS_CLINIT);
817 call_class_initializer(THREAD);
818 }
819
820 // Step 9
821 if (!HAS_PENDING_EXCEPTION) {
822 set_initialization_state_and_notify(fully_initialized, CHECK);
823 {
824 debug_only(vtable().verify(tty, true);)
825 }
826 }
827 else {
828 // Step 10 and 11
829 Handle e(THREAD, PENDING_EXCEPTION);
830 CLEAR_PENDING_EXCEPTION;
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 EXCEPTION_MARK;
836 // Wrap anything but errors into ExceptionInInitializerError.
837 if (!e->is_a(SystemDictionary::Error_klass())) {
838 JavaCallArguments args(e);
839 Handle h_loader(THREAD, NULL);
840 Handle h_prot(THREAD, NULL);
841 Handle h_cause(THREAD, NULL);
842 e = Exceptions::new_exception(THREAD, vmSymbols::java_lang_ExceptionInInitializerError(),
843 vmSymbols::throwable_void_signature(), &args, h_cause, h_loader, h_prot);
844 // If we failed to wrap, something like an OOM must have
845 // occurred - just pass that on. The previous code does the
846 // wrapping after the CLEAR_PENDING_EXCEPTION below (with
847 // identical effect for the user), but we want to store the
848 // wrapped exception as exception_thrown_during_clinit, so we
849 // must wrap it here. In fact, whatever is thrown during
850 // wrapping (Error or RuntimeException) is passed on to the
851 // caller.
852 if (HAS_PENDING_EXCEPTION) {
853 e = Handle(THREAD, PENDING_EXCEPTION);
854 CLEAR_PENDING_EXCEPTION; // Ignore any exception thrown, e is thrown below.
855 }
856 }
857
858 // Store the exception that originally caused clinit to fail so it can be
859 // chained in later NoClassDefFoundErrors.
860 set_exception_thrown_during_clinit(Handle(THREAD, java_mirror()), e, THREAD);
861 set_initialization_state_and_notify(initialization_error, THREAD);
862 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
863 // JVMTI has already reported the pending exception
864 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
865 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
866 }
867 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
868 THROW_OOP(e());
869 }
870 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
871 }
872
873 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
874 Handle h_init_lock(THREAD, init_lock());
875 if (h_init_lock() != NULL) {
876 ObjectLocker ol(h_init_lock, THREAD);
877 set_init_state(state);
878 fence_and_clear_init_lock();
879 ol.notify_all(CHECK);
880 } else {
881 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
882 set_init_state(state);
883 }
884 }
885
886 // The embedded _implementor field can only record one implementor.
887 // When there are more than one implementors, the _implementor field
888 // is set to the interface Klass* itself. Following are the possible
889 // values for the _implementor field:
890 // NULL - no implementor
891 // implementor Klass* - one implementor
892 // self - more than one implementor
893 //
894 // The _implementor field only exists for interfaces.
895 void InstanceKlass::add_implementor(Klass* k) {
896 assert(Compile_lock->owned_by_self(), "");
897 assert(is_interface(), "not interface");
898 // Filter out my subinterfaces.
899 // (Note: Interfaces are never on the subklass list.)
900 if (InstanceKlass::cast(k)->is_interface()) return;
901
902 // Filter out subclasses whose supers already implement me.
903 // (Note: CHA must walk subclasses of direct implementors
904 // in order to locate indirect implementors.)
905 Klass* sk = k->super();
906 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
907 // We only need to check one immediate superclass, since the
908 // implements_interface query looks at transitive_interfaces.
909 // Any supers of the super have the same (or fewer) transitive_interfaces.
910 return;
911
912 Klass* ik = implementor();
913 if (ik == NULL) {
914 set_implementor(k);
915 } else if (ik != this) {
916 // There is already an implementor. Use itself as an indicator of
917 // more than one implementors.
918 set_implementor(this);
919 }
920
921 // The implementor also implements the transitive_interfaces
922 for (int index = 0; index < local_interfaces()->length(); index++) {
923 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
924 }
925 }
926
927 void InstanceKlass::init_implementor() {
928 if (is_interface()) {
929 set_implementor(NULL);
930 }
931 }
932
933
934 void InstanceKlass::process_interfaces(Thread *thread) {
935 // link this class into the implementors list of every interface it implements
936 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
937 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
938 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
939 assert(interf->is_interface(), "expected interface");
940 interf->add_implementor(this);
941 }
942 }
943
944 bool InstanceKlass::can_be_primary_super_slow() const {
945 if (is_interface())
946 return false;
947 else
948 return Klass::can_be_primary_super_slow();
949 }
950
951 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
952 Array<Klass*>* transitive_interfaces) {
953 // The secondaries are the implemented interfaces.
954 Array<Klass*>* interfaces = transitive_interfaces;
955 int num_secondaries = num_extra_slots + interfaces->length();
956 if (num_secondaries == 0) {
957 // Must share this for correct bootstrapping!
958 set_secondary_supers(Universe::the_empty_klass_array());
959 return NULL;
960 } else if (num_extra_slots == 0) {
961 // The secondary super list is exactly the same as the transitive interfaces.
962 // Redefine classes has to be careful not to delete this!
963 set_secondary_supers(interfaces);
964 return NULL;
965 } else {
966 // Copy transitive interfaces to a temporary growable array to be constructed
967 // into the secondary super list with extra slots.
968 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
969 for (int i = 0; i < interfaces->length(); i++) {
970 secondaries->push(interfaces->at(i));
971 }
972 return secondaries;
973 }
974 }
975
976 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
977 if (k->is_interface()) {
978 return implements_interface(k);
979 } else {
980 return Klass::compute_is_subtype_of(k);
981 }
982 }
983
984 bool InstanceKlass::implements_interface(Klass* k) const {
985 if (this == k) return true;
986 assert(k->is_interface(), "should be an interface class");
987 for (int i = 0; i < transitive_interfaces()->length(); i++) {
988 if (transitive_interfaces()->at(i) == k) {
989 return true;
990 }
991 }
992 return false;
993 }
994
995 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
996 // Verify direct super interface
997 if (this == k) return true;
998 assert(k->is_interface(), "should be an interface class");
999 for (int i = 0; i < local_interfaces()->length(); i++) {
1000 if (local_interfaces()->at(i) == k) {
1001 return true;
1002 }
1003 }
1004 return false;
1005 }
1006
1007 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1008 if (length < 0) {
1009 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1010 }
1011 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1012 report_java_out_of_memory("Requested array size exceeds VM limit");
1013 JvmtiExport::post_array_size_exhausted();
1014 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1015 }
1016 int size = objArrayOopDesc::object_size(length);
1017 Klass* ak = array_klass(n, CHECK_NULL);
1018 objArrayOop o =
1019 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1020 return o;
1021 }
1022
1023 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1024 if (TraceFinalizerRegistration) {
1025 tty->print("Registered ");
1026 i->print_value_on(tty);
1027 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1028 }
1029 instanceHandle h_i(THREAD, i);
1030 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1031 JavaValue result(T_VOID);
1032 JavaCallArguments args(h_i);
1033 methodHandle mh (THREAD, Universe::finalizer_register_method());
1034 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1035 return h_i();
1036 }
1037
1038 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1039 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1040 int size = size_helper(); // Query before forming handle.
1041
1042 instanceOop i;
1043
1044 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1045 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1046 i = register_finalizer(i, CHECK_NULL);
1047 }
1048 return i;
1049 }
1050
1051 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1052 return instanceHandle(THREAD, allocate_instance(THREAD));
1053 }
1054
1055 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1056 if (is_interface() || is_abstract()) {
1057 ResourceMark rm(THREAD);
1058 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1059 : vmSymbols::java_lang_InstantiationException(), external_name());
1060 }
1061 if (this == SystemDictionary::Class_klass()) {
1062 ResourceMark rm(THREAD);
1063 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1064 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1065 }
1066 }
1067
1068 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1069 // Need load-acquire for lock-free read
1070 if (array_klasses_acquire() == NULL) {
1071 if (or_null) return NULL;
1072
1073 ResourceMark rm;
1074 JavaThread *jt = (JavaThread *)THREAD;
1075 {
1076 // Atomic creation of array_klasses
1077 MutexLocker mc(Compile_lock, THREAD); // for vtables
1078 MutexLocker ma(MultiArray_lock, THREAD);
1079
1080 // Check if update has already taken place
1081 if (array_klasses() == NULL) {
1082 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1083 // use 'release' to pair with lock-free load
1084 release_set_array_klasses(k);
1085 }
1086 }
1087 }
1088 // _this will always be set at this point
1089 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1090 if (or_null) {
1091 return oak->array_klass_or_null(n);
1092 }
1093 return oak->array_klass(n, THREAD);
1094 }
1095
1096 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1097 return array_klass_impl(or_null, 1, THREAD);
1098 }
1099
1100 static int call_class_initializer_counter = 0; // for debugging
1101
1102 Method* InstanceKlass::class_initializer() const {
1103 Method* clinit = find_method(
1104 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1105 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1106 return clinit;
1107 }
1108 return NULL;
1109 }
1110
1111 void InstanceKlass::call_class_initializer(TRAPS) {
1112 if (ReplayCompiles &&
1113 (ReplaySuppressInitializers == 1 ||
1114 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1115 // Hide the existence of the initializer for the purpose of replaying the compile
1116 return;
1117 }
1118
1119 methodHandle h_method(THREAD, class_initializer());
1120 assert(!is_initialized(), "we cannot initialize twice");
1121 LogTarget(Info, class, init) lt;
1122 if (lt.is_enabled()) {
1123 ResourceMark rm;
1124 LogStream ls(lt);
1125 ls.print("%d Initializing ", call_class_initializer_counter++);
1126 name()->print_value_on(&ls);
1127 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1128 }
1129 if (h_method() != NULL) {
1130 JavaCallArguments args; // No arguments
1131 JavaValue result(T_VOID);
1132 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1133 }
1134 }
1135
1136
1137 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1138 InterpreterOopMap* entry_for) {
1139 // Lazily create the _oop_map_cache at first request
1140 // Lock-free access requires load_acquire.
1141 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1142 if (oop_map_cache == NULL) {
1143 MutexLocker x(OopMapCacheAlloc_lock);
1144 // Check if _oop_map_cache was allocated while we were waiting for this lock
1145 if ((oop_map_cache = _oop_map_cache) == NULL) {
1146 oop_map_cache = new OopMapCache();
1147 // Ensure _oop_map_cache is stable, since it is examined without a lock
1148 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1149 }
1150 }
1151 // _oop_map_cache is constant after init; lookup below does its own locking.
1152 oop_map_cache->lookup(method, bci, entry_for);
1153 }
1154
1155
1156 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1157 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1158 Symbol* f_name = fs.name();
1159 Symbol* f_sig = fs.signature();
1160 if (f_name == name && f_sig == sig) {
1161 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1162 return true;
1163 }
1164 }
1165 return false;
1166 }
1167
1168
1169 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1170 const int n = local_interfaces()->length();
1171 for (int i = 0; i < n; i++) {
1172 Klass* intf1 = local_interfaces()->at(i);
1173 assert(intf1->is_interface(), "just checking type");
1174 // search for field in current interface
1175 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1176 assert(fd->is_static(), "interface field must be static");
1177 return intf1;
1178 }
1179 // search for field in direct superinterfaces
1180 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1181 if (intf2 != NULL) return intf2;
1182 }
1183 // otherwise field lookup fails
1184 return NULL;
1185 }
1186
1187
1188 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1189 // search order according to newest JVM spec (5.4.3.2, p.167).
1190 // 1) search for field in current klass
1191 if (find_local_field(name, sig, fd)) {
1192 return const_cast<InstanceKlass*>(this);
1193 }
1194 // 2) search for field recursively in direct superinterfaces
1195 { Klass* intf = find_interface_field(name, sig, fd);
1196 if (intf != NULL) return intf;
1197 }
1198 // 3) apply field lookup recursively if superclass exists
1199 { Klass* supr = super();
1200 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1201 }
1202 // 4) otherwise field lookup fails
1203 return NULL;
1204 }
1205
1206
1207 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1208 // search order according to newest JVM spec (5.4.3.2, p.167).
1209 // 1) search for field in current klass
1210 if (find_local_field(name, sig, fd)) {
1211 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1212 }
1213 // 2) search for field recursively in direct superinterfaces
1214 if (is_static) {
1215 Klass* intf = find_interface_field(name, sig, fd);
1216 if (intf != NULL) return intf;
1217 }
1218 // 3) apply field lookup recursively if superclass exists
1219 { Klass* supr = super();
1220 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1221 }
1222 // 4) otherwise field lookup fails
1223 return NULL;
1224 }
1225
1226
1227 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1228 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1229 if (fs.offset() == offset) {
1230 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1231 if (fd->is_static() == is_static) return true;
1232 }
1233 }
1234 return false;
1235 }
1236
1237
1238 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1239 Klass* klass = const_cast<InstanceKlass*>(this);
1240 while (klass != NULL) {
1241 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1242 return true;
1243 }
1244 klass = klass->super();
1245 }
1246 return false;
1247 }
1248
1249
1250 void InstanceKlass::methods_do(void f(Method* method)) {
1251 // Methods aren't stable until they are loaded. This can be read outside
1252 // a lock through the ClassLoaderData for profiling
1253 if (!is_loaded()) {
1254 return;
1255 }
1256
1257 int len = methods()->length();
1258 for (int index = 0; index < len; index++) {
1259 Method* m = methods()->at(index);
1260 assert(m->is_method(), "must be method");
1261 f(m);
1262 }
1263 }
1264
1265
1266 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1267 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1268 if (fs.access_flags().is_static()) {
1269 fieldDescriptor& fd = fs.field_descriptor();
1270 cl->do_field(&fd);
1271 }
1272 }
1273 }
1274
1275
1276 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1277 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1278 if (fs.access_flags().is_static()) {
1279 fieldDescriptor& fd = fs.field_descriptor();
1280 f(&fd, mirror, CHECK);
1281 }
1282 }
1283 }
1284
1285
1286 static int compare_fields_by_offset(int* a, int* b) {
1287 return a[0] - b[0];
1288 }
1289
1290 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1291 InstanceKlass* super = superklass();
1292 if (super != NULL) {
1293 super->do_nonstatic_fields(cl);
1294 }
1295 fieldDescriptor fd;
1296 int length = java_fields_count();
1297 // In DebugInfo nonstatic fields are sorted by offset.
1298 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1299 int j = 0;
1300 for (int i = 0; i < length; i += 1) {
1301 fd.reinitialize(this, i);
1302 if (!fd.is_static()) {
1303 fields_sorted[j + 0] = fd.offset();
1304 fields_sorted[j + 1] = i;
1305 j += 2;
1306 }
1307 }
1308 if (j > 0) {
1309 length = j;
1310 // _sort_Fn is defined in growableArray.hpp.
1311 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1312 for (int i = 0; i < length; i += 2) {
1313 fd.reinitialize(this, fields_sorted[i + 1]);
1314 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1315 cl->do_field(&fd);
1316 }
1317 }
1318 FREE_C_HEAP_ARRAY(int, fields_sorted);
1319 }
1320
1321
1322 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1323 if (array_klasses() != NULL)
1324 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1325 }
1326
1327 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1328 if (array_klasses() != NULL)
1329 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1330 }
1331
1332 #ifdef ASSERT
1333 static int linear_search(const Array<Method*>* methods,
1334 const Symbol* name,
1335 const Symbol* signature) {
1336 const int len = methods->length();
1337 for (int index = 0; index < len; index++) {
1338 const Method* const m = methods->at(index);
1339 assert(m->is_method(), "must be method");
1340 if (m->signature() == signature && m->name() == name) {
1341 return index;
1342 }
1343 }
1344 return -1;
1345 }
1346 #endif
1347
1348 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1349 int len = methods->length();
1350 // methods are sorted, so do binary search
1351 int l = 0;
1352 int h = len - 1;
1353 while (l <= h) {
1354 int mid = (l + h) >> 1;
1355 Method* m = methods->at(mid);
1356 assert(m->is_method(), "must be method");
1357 int res = m->name()->fast_compare(name);
1358 if (res == 0) {
1359 return mid;
1360 } else if (res < 0) {
1361 l = mid + 1;
1362 } else {
1363 h = mid - 1;
1364 }
1365 }
1366 return -1;
1367 }
1368
1369 // find_method looks up the name/signature in the local methods array
1370 Method* InstanceKlass::find_method(const Symbol* name,
1371 const Symbol* signature) const {
1372 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1373 }
1374
1375 Method* InstanceKlass::find_method_impl(const Symbol* name,
1376 const Symbol* signature,
1377 OverpassLookupMode overpass_mode,
1378 StaticLookupMode static_mode,
1379 PrivateLookupMode private_mode) const {
1380 return InstanceKlass::find_method_impl(methods(),
1381 name,
1382 signature,
1383 overpass_mode,
1384 static_mode,
1385 private_mode);
1386 }
1387
1388 // find_instance_method looks up the name/signature in the local methods array
1389 // and skips over static methods
1390 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1391 const Symbol* name,
1392 const Symbol* signature) {
1393 Method* const meth = InstanceKlass::find_method_impl(methods,
1394 name,
1395 signature,
1396 find_overpass,
1397 skip_static,
1398 find_private);
1399 assert(((meth == NULL) || !meth->is_static()),
1400 "find_instance_method should have skipped statics");
1401 return meth;
1402 }
1403
1404 // find_instance_method looks up the name/signature in the local methods array
1405 // and skips over static methods
1406 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1407 return InstanceKlass::find_instance_method(methods(), name, signature);
1408 }
1409
1410 // Find looks up the name/signature in the local methods array
1411 // and filters on the overpass, static and private flags
1412 // This returns the first one found
1413 // note that the local methods array can have up to one overpass, one static
1414 // and one instance (private or not) with the same name/signature
1415 Method* InstanceKlass::find_local_method(const Symbol* name,
1416 const Symbol* signature,
1417 OverpassLookupMode overpass_mode,
1418 StaticLookupMode static_mode,
1419 PrivateLookupMode private_mode) const {
1420 return InstanceKlass::find_method_impl(methods(),
1421 name,
1422 signature,
1423 overpass_mode,
1424 static_mode,
1425 private_mode);
1426 }
1427
1428 // Find looks up the name/signature in the local methods array
1429 // and filters on the overpass, static and private flags
1430 // This returns the first one found
1431 // note that the local methods array can have up to one overpass, one static
1432 // and one instance (private or not) with the same name/signature
1433 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1434 const Symbol* name,
1435 const Symbol* signature,
1436 OverpassLookupMode overpass_mode,
1437 StaticLookupMode static_mode,
1438 PrivateLookupMode private_mode) {
1439 return InstanceKlass::find_method_impl(methods,
1440 name,
1441 signature,
1442 overpass_mode,
1443 static_mode,
1444 private_mode);
1445 }
1446
1447 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1448 const Symbol* name,
1449 const Symbol* signature) {
1450 return InstanceKlass::find_method_impl(methods,
1451 name,
1452 signature,
1453 find_overpass,
1454 find_static,
1455 find_private);
1456 }
1457
1458 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1459 const Symbol* name,
1460 const Symbol* signature,
1461 OverpassLookupMode overpass_mode,
1462 StaticLookupMode static_mode,
1463 PrivateLookupMode private_mode) {
1464 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1465 return hit >= 0 ? methods->at(hit): NULL;
1466 }
1467
1468 // true if method matches signature and conforms to skipping_X conditions.
1469 static bool method_matches(const Method* m,
1470 const Symbol* signature,
1471 bool skipping_overpass,
1472 bool skipping_static,
1473 bool skipping_private) {
1474 return ((m->signature() == signature) &&
1475 (!skipping_overpass || !m->is_overpass()) &&
1476 (!skipping_static || !m->is_static()) &&
1477 (!skipping_private || !m->is_private()));
1478 }
1479
1480 // Used directly for default_methods to find the index into the
1481 // default_vtable_indices, and indirectly by find_method
1482 // find_method_index looks in the local methods array to return the index
1483 // of the matching name/signature. If, overpass methods are being ignored,
1484 // the search continues to find a potential non-overpass match. This capability
1485 // is important during method resolution to prefer a static method, for example,
1486 // over an overpass method.
1487 // There is the possibility in any _method's array to have the same name/signature
1488 // for a static method, an overpass method and a local instance method
1489 // To correctly catch a given method, the search criteria may need
1490 // to explicitly skip the other two. For local instance methods, it
1491 // is often necessary to skip private methods
1492 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1493 const Symbol* name,
1494 const Symbol* signature,
1495 OverpassLookupMode overpass_mode,
1496 StaticLookupMode static_mode,
1497 PrivateLookupMode private_mode) {
1498 const bool skipping_overpass = (overpass_mode == skip_overpass);
1499 const bool skipping_static = (static_mode == skip_static);
1500 const bool skipping_private = (private_mode == skip_private);
1501 const int hit = binary_search(methods, name);
1502 if (hit != -1) {
1503 const Method* const m = methods->at(hit);
1504
1505 // Do linear search to find matching signature. First, quick check
1506 // for common case, ignoring overpasses if requested.
1507 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1508 return hit;
1509 }
1510
1511 // search downwards through overloaded methods
1512 int i;
1513 for (i = hit - 1; i >= 0; --i) {
1514 const Method* const m = methods->at(i);
1515 assert(m->is_method(), "must be method");
1516 if (m->name() != name) {
1517 break;
1518 }
1519 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1520 return i;
1521 }
1522 }
1523 // search upwards
1524 for (i = hit + 1; i < methods->length(); ++i) {
1525 const Method* const m = methods->at(i);
1526 assert(m->is_method(), "must be method");
1527 if (m->name() != name) {
1528 break;
1529 }
1530 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1531 return i;
1532 }
1533 }
1534 // not found
1535 #ifdef ASSERT
1536 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1537 linear_search(methods, name, signature);
1538 assert(-1 == index, "binary search should have found entry %d", index);
1539 #endif
1540 }
1541 return -1;
1542 }
1543
1544 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1545 return find_method_by_name(methods(), name, end);
1546 }
1547
1548 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1549 const Symbol* name,
1550 int* end_ptr) {
1551 assert(end_ptr != NULL, "just checking");
1552 int start = binary_search(methods, name);
1553 int end = start + 1;
1554 if (start != -1) {
1555 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1556 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1557 *end_ptr = end;
1558 return start;
1559 }
1560 return -1;
1561 }
1562
1563 // uncached_lookup_method searches both the local class methods array and all
1564 // superclasses methods arrays, skipping any overpass methods in superclasses.
1565 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1566 const Symbol* signature,
1567 OverpassLookupMode overpass_mode) const {
1568 OverpassLookupMode overpass_local_mode = overpass_mode;
1569 const Klass* klass = this;
1570 while (klass != NULL) {
1571 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1572 signature,
1573 overpass_local_mode,
1574 find_static,
1575 find_private);
1576 if (method != NULL) {
1577 return method;
1578 }
1579 klass = klass->super();
1580 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1581 }
1582 return NULL;
1583 }
1584
1585 #ifdef ASSERT
1586 // search through class hierarchy and return true if this class or
1587 // one of the superclasses was redefined
1588 bool InstanceKlass::has_redefined_this_or_super() const {
1589 const Klass* klass = this;
1590 while (klass != NULL) {
1591 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1592 return true;
1593 }
1594 klass = klass->super();
1595 }
1596 return false;
1597 }
1598 #endif
1599
1600 // lookup a method in the default methods list then in all transitive interfaces
1601 // Do NOT return private or static methods
1602 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1603 Symbol* signature) const {
1604 Method* m = NULL;
1605 if (default_methods() != NULL) {
1606 m = find_method(default_methods(), name, signature);
1607 }
1608 // Look up interfaces
1609 if (m == NULL) {
1610 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1611 }
1612 return m;
1613 }
1614
1615 // lookup a method in all the interfaces that this class implements
1616 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1617 // They should only be found in the initial InterfaceMethodRef
1618 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1619 Symbol* signature,
1620 DefaultsLookupMode defaults_mode) const {
1621 Array<Klass*>* all_ifs = transitive_interfaces();
1622 int num_ifs = all_ifs->length();
1623 InstanceKlass *ik = NULL;
1624 for (int i = 0; i < num_ifs; i++) {
1625 ik = InstanceKlass::cast(all_ifs->at(i));
1626 Method* m = ik->lookup_method(name, signature);
1627 if (m != NULL && m->is_public() && !m->is_static() &&
1628 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1629 return m;
1630 }
1631 }
1632 return NULL;
1633 }
1634
1635 /* jni_id_for_impl for jfieldIds only */
1636 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1637 MutexLocker ml(JfieldIdCreation_lock);
1638 // Retry lookup after we got the lock
1639 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1640 if (probe == NULL) {
1641 // Slow case, allocate new static field identifier
1642 probe = new JNIid(this, offset, jni_ids());
1643 set_jni_ids(probe);
1644 }
1645 return probe;
1646 }
1647
1648
1649 /* jni_id_for for jfieldIds only */
1650 JNIid* InstanceKlass::jni_id_for(int offset) {
1651 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1652 if (probe == NULL) {
1653 probe = jni_id_for_impl(offset);
1654 }
1655 return probe;
1656 }
1657
1658 u2 InstanceKlass::enclosing_method_data(int offset) const {
1659 const Array<jushort>* const inner_class_list = inner_classes();
1660 if (inner_class_list == NULL) {
1661 return 0;
1662 }
1663 const int length = inner_class_list->length();
1664 if (length % inner_class_next_offset == 0) {
1665 return 0;
1666 }
1667 const int index = length - enclosing_method_attribute_size;
1668 assert(offset < enclosing_method_attribute_size, "invalid offset");
1669 return inner_class_list->at(index + offset);
1670 }
1671
1672 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1673 u2 method_index) {
1674 Array<jushort>* inner_class_list = inner_classes();
1675 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1676 int length = inner_class_list->length();
1677 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1678 int index = length - enclosing_method_attribute_size;
1679 inner_class_list->at_put(
1680 index + enclosing_method_class_index_offset, class_index);
1681 inner_class_list->at_put(
1682 index + enclosing_method_method_index_offset, method_index);
1683 }
1684 }
1685
1686 // Lookup or create a jmethodID.
1687 // This code is called by the VMThread and JavaThreads so the
1688 // locking has to be done very carefully to avoid deadlocks
1689 // and/or other cache consistency problems.
1690 //
1691 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1692 size_t idnum = (size_t)method_h->method_idnum();
1693 jmethodID* jmeths = methods_jmethod_ids_acquire();
1694 size_t length = 0;
1695 jmethodID id = NULL;
1696
1697 // We use a double-check locking idiom here because this cache is
1698 // performance sensitive. In the normal system, this cache only
1699 // transitions from NULL to non-NULL which is safe because we use
1700 // release_set_methods_jmethod_ids() to advertise the new cache.
1701 // A partially constructed cache should never be seen by a racing
1702 // thread. We also use release_store() to save a new jmethodID
1703 // in the cache so a partially constructed jmethodID should never be
1704 // seen either. Cache reads of existing jmethodIDs proceed without a
1705 // lock, but cache writes of a new jmethodID requires uniqueness and
1706 // creation of the cache itself requires no leaks so a lock is
1707 // generally acquired in those two cases.
1708 //
1709 // If the RedefineClasses() API has been used, then this cache can
1710 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1711 // Cache creation requires no leaks and we require safety between all
1712 // cache accesses and freeing of the old cache so a lock is generally
1713 // acquired when the RedefineClasses() API has been used.
1714
1715 if (jmeths != NULL) {
1716 // the cache already exists
1717 if (!idnum_can_increment()) {
1718 // the cache can't grow so we can just get the current values
1719 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1720 } else {
1721 // cache can grow so we have to be more careful
1722 if (Threads::number_of_threads() == 0 ||
1723 SafepointSynchronize::is_at_safepoint()) {
1724 // we're single threaded or at a safepoint - no locking needed
1725 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1726 } else {
1727 MutexLocker ml(JmethodIdCreation_lock);
1728 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1729 }
1730 }
1731 }
1732 // implied else:
1733 // we need to allocate a cache so default length and id values are good
1734
1735 if (jmeths == NULL || // no cache yet
1736 length <= idnum || // cache is too short
1737 id == NULL) { // cache doesn't contain entry
1738
1739 // This function can be called by the VMThread so we have to do all
1740 // things that might block on a safepoint before grabbing the lock.
1741 // Otherwise, we can deadlock with the VMThread or have a cache
1742 // consistency issue. These vars keep track of what we might have
1743 // to free after the lock is dropped.
1744 jmethodID to_dealloc_id = NULL;
1745 jmethodID* to_dealloc_jmeths = NULL;
1746
1747 // may not allocate new_jmeths or use it if we allocate it
1748 jmethodID* new_jmeths = NULL;
1749 if (length <= idnum) {
1750 // allocate a new cache that might be used
1751 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1752 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1753 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1754 // cache size is stored in element[0], other elements offset by one
1755 new_jmeths[0] = (jmethodID)size;
1756 }
1757
1758 // allocate a new jmethodID that might be used
1759 jmethodID new_id = NULL;
1760 if (method_h->is_old() && !method_h->is_obsolete()) {
1761 // The method passed in is old (but not obsolete), we need to use the current version
1762 Method* current_method = method_with_idnum((int)idnum);
1763 assert(current_method != NULL, "old and but not obsolete, so should exist");
1764 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1765 } else {
1766 // It is the current version of the method or an obsolete method,
1767 // use the version passed in
1768 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1769 }
1770
1771 if (Threads::number_of_threads() == 0 ||
1772 SafepointSynchronize::is_at_safepoint()) {
1773 // we're single threaded or at a safepoint - no locking needed
1774 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1775 &to_dealloc_id, &to_dealloc_jmeths);
1776 } else {
1777 MutexLocker ml(JmethodIdCreation_lock);
1778 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1779 &to_dealloc_id, &to_dealloc_jmeths);
1780 }
1781
1782 // The lock has been dropped so we can free resources.
1783 // Free up either the old cache or the new cache if we allocated one.
1784 if (to_dealloc_jmeths != NULL) {
1785 FreeHeap(to_dealloc_jmeths);
1786 }
1787 // free up the new ID since it wasn't needed
1788 if (to_dealloc_id != NULL) {
1789 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1790 }
1791 }
1792 return id;
1793 }
1794
1795 // Figure out how many jmethodIDs haven't been allocated, and make
1796 // sure space for them is pre-allocated. This makes getting all
1797 // method ids much, much faster with classes with more than 8
1798 // methods, and has a *substantial* effect on performance with jvmti
1799 // code that loads all jmethodIDs for all classes.
1800 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1801 int new_jmeths = 0;
1802 int length = methods()->length();
1803 for (int index = start_offset; index < length; index++) {
1804 Method* m = methods()->at(index);
1805 jmethodID id = m->find_jmethod_id_or_null();
1806 if (id == NULL) {
1807 new_jmeths++;
1808 }
1809 }
1810 if (new_jmeths != 0) {
1811 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1812 }
1813 }
1814
1815 // Common code to fetch the jmethodID from the cache or update the
1816 // cache with the new jmethodID. This function should never do anything
1817 // that causes the caller to go to a safepoint or we can deadlock with
1818 // the VMThread or have cache consistency issues.
1819 //
1820 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1821 size_t idnum, jmethodID new_id,
1822 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1823 jmethodID** to_dealloc_jmeths_p) {
1824 assert(new_id != NULL, "sanity check");
1825 assert(to_dealloc_id_p != NULL, "sanity check");
1826 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1827 assert(Threads::number_of_threads() == 0 ||
1828 SafepointSynchronize::is_at_safepoint() ||
1829 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1830
1831 // reacquire the cache - we are locked, single threaded or at a safepoint
1832 jmethodID* jmeths = methods_jmethod_ids_acquire();
1833 jmethodID id = NULL;
1834 size_t length = 0;
1835
1836 if (jmeths == NULL || // no cache yet
1837 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1838 if (jmeths != NULL) {
1839 // copy any existing entries from the old cache
1840 for (size_t index = 0; index < length; index++) {
1841 new_jmeths[index+1] = jmeths[index+1];
1842 }
1843 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1844 }
1845 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1846 } else {
1847 // fetch jmethodID (if any) from the existing cache
1848 id = jmeths[idnum+1];
1849 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1850 }
1851 if (id == NULL) {
1852 // No matching jmethodID in the existing cache or we have a new
1853 // cache or we just grew the cache. This cache write is done here
1854 // by the first thread to win the foot race because a jmethodID
1855 // needs to be unique once it is generally available.
1856 id = new_id;
1857
1858 // The jmethodID cache can be read while unlocked so we have to
1859 // make sure the new jmethodID is complete before installing it
1860 // in the cache.
1861 OrderAccess::release_store(&jmeths[idnum+1], id);
1862 } else {
1863 *to_dealloc_id_p = new_id; // save new id for later delete
1864 }
1865 return id;
1866 }
1867
1868
1869 // Common code to get the jmethodID cache length and the jmethodID
1870 // value at index idnum if there is one.
1871 //
1872 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1873 size_t idnum, size_t *length_p, jmethodID* id_p) {
1874 assert(cache != NULL, "sanity check");
1875 assert(length_p != NULL, "sanity check");
1876 assert(id_p != NULL, "sanity check");
1877
1878 // cache size is stored in element[0], other elements offset by one
1879 *length_p = (size_t)cache[0];
1880 if (*length_p <= idnum) { // cache is too short
1881 *id_p = NULL;
1882 } else {
1883 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1884 }
1885 }
1886
1887
1888 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1889 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1890 size_t idnum = (size_t)method->method_idnum();
1891 jmethodID* jmeths = methods_jmethod_ids_acquire();
1892 size_t length; // length assigned as debugging crumb
1893 jmethodID id = NULL;
1894 if (jmeths != NULL && // If there is a cache
1895 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1896 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1897 }
1898 return id;
1899 }
1900
1901 inline DependencyContext InstanceKlass::dependencies() {
1902 DependencyContext dep_context(&_dep_context);
1903 return dep_context;
1904 }
1905
1906 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1907 return dependencies().mark_dependent_nmethods(changes);
1908 }
1909
1910 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1911 dependencies().add_dependent_nmethod(nm);
1912 }
1913
1914 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1915 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1916 }
1917
1918 #ifndef PRODUCT
1919 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1920 dependencies().print_dependent_nmethods(verbose);
1921 }
1922
1923 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1924 return dependencies().is_dependent_nmethod(nm);
1925 }
1926 #endif //PRODUCT
1927
1928 void InstanceKlass::clean_weak_instanceklass_links() {
1929 clean_implementors_list();
1930 clean_method_data();
1931
1932 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1933 DependencyContext dep_context(&_dep_context);
1934 dep_context.expunge_stale_entries();
1935 }
1936
1937 void InstanceKlass::clean_implementors_list() {
1938 assert(is_loader_alive(), "this klass should be live");
1939 if (is_interface()) {
1940 if (ClassUnloading) {
1941 Klass* impl = implementor();
1942 if (impl != NULL) {
1943 if (!impl->is_loader_alive()) {
1944 // remove this guy
1945 Klass** klass = adr_implementor();
1946 assert(klass != NULL, "null klass");
1947 if (klass != NULL) {
1948 *klass = NULL;
1949 }
1950 }
1951 }
1952 }
1953 }
1954 }
1955
1956 void InstanceKlass::clean_method_data() {
1957 for (int m = 0; m < methods()->length(); m++) {
1958 MethodData* mdo = methods()->at(m)->method_data();
1959 if (mdo != NULL) {
1960 mdo->clean_method_data(/*always_clean*/false);
1961 }
1962 }
1963 }
1964
1965 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
1966 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
1967 ResourceMark rm;
1968 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
1969 return false;
1970 }
1971
1972 Array<Klass*>* local_interfaces = this->local_interfaces();
1973 if (local_interfaces != NULL) {
1974 int length = local_interfaces->length();
1975 for (int i = 0; i < length; i++) {
1976 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
1977 if (!intf->has_passed_fingerprint_check()) {
1978 ResourceMark rm;
1979 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
1980 return false;
1981 }
1982 }
1983 }
1984
1985 return true;
1986 }
1987
1988 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
1989 #if INCLUDE_AOT
1990 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
1991 if (CalculateClassFingerprint) {
1992 // (1) We are running AOT to generate a shared library.
1993 return true;
1994 }
1995 if (DumpSharedSpaces) {
1996 // (2) We are running -Xshare:dump to create a shared archive
1997 return true;
1998 }
1999 if (UseAOT && is_anonymous) {
2000 // (3) We are using AOT code from a shared library and see an anonymous class
2001 return true;
2002 }
2003 #endif
2004
2005 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2006 // but do not store the 64-bit fingerprint to save space.
2007 return false;
2008 }
2009
2010 bool InstanceKlass::has_stored_fingerprint() const {
2011 #if INCLUDE_AOT
2012 return should_store_fingerprint() || is_shared();
2013 #else
2014 return false;
2015 #endif
2016 }
2017
2018 uint64_t InstanceKlass::get_stored_fingerprint() const {
2019 address adr = adr_fingerprint();
2020 if (adr != NULL) {
2021 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2022 }
2023 return 0;
2024 }
2025
2026 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2027 address adr = adr_fingerprint();
2028 if (adr != NULL) {
2029 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2030
2031 ResourceMark rm;
2032 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2033 }
2034 }
2035
2036 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2037 Klass::metaspace_pointers_do(it);
2038
2039 if (log_is_enabled(Trace, cds)) {
2040 ResourceMark rm;
2041 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2042 }
2043
2044 it->push(&_annotations);
2045 it->push((Klass**)&_array_klasses);
2046 it->push(&_constants);
2047 it->push(&_inner_classes);
2048 it->push(&_array_name);
2049 #if INCLUDE_JVMTI
2050 it->push(&_previous_versions);
2051 #endif
2052 it->push(&_methods);
2053 it->push(&_default_methods);
2054 it->push(&_local_interfaces);
2055 it->push(&_transitive_interfaces);
2056 it->push(&_method_ordering);
2057 it->push(&_default_vtable_indices);
2058 it->push(&_fields);
2059
2060 if (itable_length() > 0) {
2061 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2062 int method_table_offset_in_words = ioe->offset()/wordSize;
2063 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2064 / itableOffsetEntry::size();
2065
2066 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2067 if (ioe->interface_klass() != NULL) {
2068 it->push(ioe->interface_klass_addr());
2069 itableMethodEntry* ime = ioe->first_method_entry(this);
2070 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2071 for (int index = 0; index < n; index ++) {
2072 it->push(ime[index].method_addr());
2073 }
2074 }
2075 }
2076 }
2077 }
2078
2079 void InstanceKlass::remove_unshareable_info() {
2080 Klass::remove_unshareable_info();
2081
2082 if (is_in_error_state()) {
2083 // Classes are attempted to link during dumping and may fail,
2084 // but these classes are still in the dictionary and class list in CLD.
2085 // Check in_error state first because in_error is > linked state, so
2086 // is_linked() is true.
2087 // If there's a linking error, there is nothing else to remove.
2088 return;
2089 }
2090
2091 // Unlink the class
2092 if (is_linked()) {
2093 unlink_class();
2094 }
2095 init_implementor();
2096
2097 constants()->remove_unshareable_info();
2098
2099 for (int i = 0; i < methods()->length(); i++) {
2100 Method* m = methods()->at(i);
2101 m->remove_unshareable_info();
2102 }
2103
2104 // do array classes also.
2105 if (array_klasses() != NULL) {
2106 array_klasses()->remove_unshareable_info();
2107 }
2108
2109 // These are not allocated from metaspace, but they should should all be empty
2110 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2111 guarantee(_source_debug_extension == NULL, "must be");
2112 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2113 guarantee(_osr_nmethods_head == NULL, "must be");
2114
2115 #if INCLUDE_JVMTI
2116 guarantee(_breakpoints == NULL, "must be");
2117 guarantee(_previous_versions == NULL, "must be");
2118 #endif
2119
2120 _init_thread = NULL;
2121 _methods_jmethod_ids = NULL;
2122 _jni_ids = NULL;
2123 _oop_map_cache = NULL;
2124 }
2125
2126 void InstanceKlass::remove_java_mirror() {
2127 Klass::remove_java_mirror();
2128
2129 // do array classes also.
2130 if (array_klasses() != NULL) {
2131 array_klasses()->remove_java_mirror();
2132 }
2133 }
2134
2135 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2136 set_package(loader_data, CHECK);
2137 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2138
2139 Array<Method*>* methods = this->methods();
2140 int num_methods = methods->length();
2141 for (int index2 = 0; index2 < num_methods; ++index2) {
2142 methodHandle m(THREAD, methods->at(index2));
2143 m->restore_unshareable_info(CHECK);
2144 }
2145 if (JvmtiExport::has_redefined_a_class()) {
2146 // Reinitialize vtable because RedefineClasses may have changed some
2147 // entries in this vtable for super classes so the CDS vtable might
2148 // point to old or obsolete entries. RedefineClasses doesn't fix up
2149 // vtables in the shared system dictionary, only the main one.
2150 // It also redefines the itable too so fix that too.
2151 ResourceMark rm(THREAD);
2152 vtable().initialize_vtable(false, CHECK);
2153 itable().initialize_itable(false, CHECK);
2154 }
2155
2156 // restore constant pool resolved references
2157 constants()->restore_unshareable_info(CHECK);
2158
2159 if (array_klasses() != NULL) {
2160 // Array classes have null protection domain.
2161 // --> see ArrayKlass::complete_create_array_klass()
2162 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2163 }
2164 }
2165
2166 // returns true IFF is_in_error_state() has been changed as a result of this call.
2167 bool InstanceKlass::check_sharing_error_state() {
2168 assert(DumpSharedSpaces, "should only be called during dumping");
2169 bool old_state = is_in_error_state();
2170
2171 if (!is_in_error_state()) {
2172 bool bad = false;
2173 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2174 if (sup->is_in_error_state()) {
2175 bad = true;
2176 break;
2177 }
2178 }
2179 if (!bad) {
2180 Array<Klass*>* interfaces = transitive_interfaces();
2181 for (int i = 0; i < interfaces->length(); i++) {
2182 Klass* iface = interfaces->at(i);
2183 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2184 bad = true;
2185 break;
2186 }
2187 }
2188 }
2189
2190 if (bad) {
2191 set_in_error_state();
2192 }
2193 }
2194
2195 return (old_state != is_in_error_state());
2196 }
2197
2198 #if INCLUDE_JVMTI
2199 static void clear_all_breakpoints(Method* m) {
2200 m->clear_all_breakpoints();
2201 }
2202 #endif
2203
2204 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2205 // notify the debugger
2206 if (JvmtiExport::should_post_class_unload()) {
2207 JvmtiExport::post_class_unload(ik);
2208 }
2209
2210 // notify ClassLoadingService of class unload
2211 ClassLoadingService::notify_class_unloaded(ik);
2212 }
2213
2214 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2215 // Clean up C heap
2216 ik->release_C_heap_structures();
2217 ik->constants()->release_C_heap_structures();
2218 }
2219
2220 void InstanceKlass::release_C_heap_structures() {
2221 // Can't release the constant pool here because the constant pool can be
2222 // deallocated separately from the InstanceKlass for default methods and
2223 // redefine classes.
2224
2225 // Deallocate oop map cache
2226 if (_oop_map_cache != NULL) {
2227 delete _oop_map_cache;
2228 _oop_map_cache = NULL;
2229 }
2230
2231 // Deallocate JNI identifiers for jfieldIDs
2232 JNIid::deallocate(jni_ids());
2233 set_jni_ids(NULL);
2234
2235 jmethodID* jmeths = methods_jmethod_ids_acquire();
2236 if (jmeths != (jmethodID*)NULL) {
2237 release_set_methods_jmethod_ids(NULL);
2238 FreeHeap(jmeths);
2239 }
2240
2241 // Release dependencies.
2242 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2243 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2244 // context can contain live dependencies, since there's a race between nmethod &
2245 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2246 // dependencies aren't removed from the context associated with the class (see
2247 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2248 // live dependencies pointing to unloaded nmethods and causes a crash in
2249 // DC::remove_all_dependents() when it touches unloaded nmethod.
2250 dependencies().wipe();
2251
2252 #if INCLUDE_JVMTI
2253 // Deallocate breakpoint records
2254 if (breakpoints() != 0x0) {
2255 methods_do(clear_all_breakpoints);
2256 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2257 }
2258
2259 // deallocate the cached class file
2260 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2261 os::free(_cached_class_file);
2262 _cached_class_file = NULL;
2263 }
2264 #endif
2265
2266 // Decrement symbol reference counts associated with the unloaded class.
2267 if (_name != NULL) _name->decrement_refcount();
2268 // unreference array name derived from this class name (arrays of an unloaded
2269 // class can't be referenced anymore).
2270 if (_array_name != NULL) _array_name->decrement_refcount();
2271 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2272 }
2273
2274 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2275 if (array == NULL) {
2276 _source_debug_extension = NULL;
2277 } else {
2278 // Adding one to the attribute length in order to store a null terminator
2279 // character could cause an overflow because the attribute length is
2280 // already coded with an u4 in the classfile, but in practice, it's
2281 // unlikely to happen.
2282 assert((length+1) > length, "Overflow checking");
2283 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2284 for (int i = 0; i < length; i++) {
2285 sde[i] = array[i];
2286 }
2287 sde[length] = '\0';
2288 _source_debug_extension = sde;
2289 }
2290 }
2291
2292 const char* InstanceKlass::signature_name() const {
2293 int hash_len = 0;
2294 char hash_buf[40];
2295
2296 // If this is an anonymous class, append a hash to make the name unique
2297 if (is_anonymous()) {
2298 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2299 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2300 hash_len = (int)strlen(hash_buf);
2301 }
2302
2303 // Get the internal name as a c string
2304 const char* src = (const char*) (name()->as_C_string());
2305 const int src_length = (int)strlen(src);
2306
2307 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2308
2309 // Add L as type indicator
2310 int dest_index = 0;
2311 dest[dest_index++] = 'L';
2312
2313 // Add the actual class name
2314 for (int src_index = 0; src_index < src_length; ) {
2315 dest[dest_index++] = src[src_index++];
2316 }
2317
2318 // If we have a hash, append it
2319 for (int hash_index = 0; hash_index < hash_len; ) {
2320 dest[dest_index++] = hash_buf[hash_index++];
2321 }
2322
2323 // Add the semicolon and the NULL
2324 dest[dest_index++] = ';';
2325 dest[dest_index] = '\0';
2326 return dest;
2327 }
2328
2329 // Used to obtain the package name from a fully qualified class name.
2330 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2331 if (name == NULL) {
2332 return NULL;
2333 } else {
2334 if (name->utf8_length() <= 0) {
2335 return NULL;
2336 }
2337 ResourceMark rm;
2338 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2339 if (package_name == NULL) {
2340 return NULL;
2341 }
2342 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2343 return pkg_name;
2344 }
2345 }
2346
2347 ModuleEntry* InstanceKlass::module() const {
2348 if (!in_unnamed_package()) {
2349 return _package_entry->module();
2350 }
2351 const Klass* host = host_klass();
2352 if (host == NULL) {
2353 return class_loader_data()->unnamed_module();
2354 }
2355 return host->class_loader_data()->unnamed_module();
2356 }
2357
2358 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2359
2360 // ensure java/ packages only loaded by boot or platform builtin loaders
2361 Handle class_loader(THREAD, loader_data->class_loader());
2362 check_prohibited_package(name(), class_loader, CHECK);
2363
2364 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2365
2366 if (pkg_name != NULL && loader_data != NULL) {
2367
2368 // Find in class loader's package entry table.
2369 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2370
2371 // If the package name is not found in the loader's package
2372 // entry table, it is an indication that the package has not
2373 // been defined. Consider it defined within the unnamed module.
2374 if (_package_entry == NULL) {
2375 ResourceMark rm;
2376
2377 if (!ModuleEntryTable::javabase_defined()) {
2378 // Before java.base is defined during bootstrapping, define all packages in
2379 // the java.base module. If a non-java.base package is erroneously placed
2380 // in the java.base module it will be caught later when java.base
2381 // is defined by ModuleEntryTable::verify_javabase_packages check.
2382 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2383 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2384 } else {
2385 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2386 _package_entry = loader_data->packages()->lookup(pkg_name,
2387 loader_data->unnamed_module());
2388 }
2389
2390 // A package should have been successfully created
2391 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2392 name()->as_C_string(), loader_data->loader_name());
2393 }
2394
2395 if (log_is_enabled(Debug, module)) {
2396 ResourceMark rm;
2397 ModuleEntry* m = _package_entry->module();
2398 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2399 external_name(),
2400 pkg_name->as_C_string(),
2401 loader_data->loader_name(),
2402 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2403 }
2404 } else {
2405 ResourceMark rm;
2406 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2407 external_name(),
2408 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2409 UNNAMED_MODULE);
2410 }
2411 }
2412
2413
2414 // different versions of is_same_class_package
2415
2416 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2417 oop classloader1 = this->class_loader();
2418 PackageEntry* classpkg1 = this->package();
2419 if (class2->is_objArray_klass()) {
2420 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2421 }
2422
2423 oop classloader2;
2424 PackageEntry* classpkg2;
2425 if (class2->is_instance_klass()) {
2426 classloader2 = class2->class_loader();
2427 classpkg2 = class2->package();
2428 } else {
2429 assert(class2->is_typeArray_klass(), "should be type array");
2430 classloader2 = NULL;
2431 classpkg2 = NULL;
2432 }
2433
2434 // Same package is determined by comparing class loader
2435 // and package entries. Both must be the same. This rule
2436 // applies even to classes that are defined in the unnamed
2437 // package, they still must have the same class loader.
2438 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2439 return true;
2440 }
2441
2442 return false;
2443 }
2444
2445 // return true if this class and other_class are in the same package. Classloader
2446 // and classname information is enough to determine a class's package
2447 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2448 const Symbol* other_class_name) const {
2449 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2450 return false;
2451 }
2452 if (name()->fast_compare(other_class_name) == 0) {
2453 return true;
2454 }
2455
2456 {
2457 ResourceMark rm;
2458
2459 bool bad_class_name = false;
2460 const char* other_pkg =
2461 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2462 if (bad_class_name) {
2463 return false;
2464 }
2465 // Check that package_from_name() returns NULL, not "", if there is no package.
2466 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2467
2468 const Symbol* const this_package_name =
2469 this->package() != NULL ? this->package()->name() : NULL;
2470
2471 if (this_package_name == NULL || other_pkg == NULL) {
2472 // One of the two doesn't have a package. Only return true if the other
2473 // one also doesn't have a package.
2474 return (const char*)this_package_name == other_pkg;
2475 }
2476
2477 // Check if package is identical
2478 return this_package_name->equals(other_pkg);
2479 }
2480 }
2481
2482 // Returns true iff super_method can be overridden by a method in targetclassname
2483 // See JLS 3rd edition 8.4.6.1
2484 // Assumes name-signature match
2485 // "this" is InstanceKlass of super_method which must exist
2486 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2487 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2488 // Private methods can not be overridden
2489 if (super_method->is_private()) {
2490 return false;
2491 }
2492 // If super method is accessible, then override
2493 if ((super_method->is_protected()) ||
2494 (super_method->is_public())) {
2495 return true;
2496 }
2497 // Package-private methods are not inherited outside of package
2498 assert(super_method->is_package_private(), "must be package private");
2499 return(is_same_class_package(targetclassloader(), targetclassname));
2500 }
2501
2502 // Only boot and platform class loaders can define classes in "java/" packages.
2503 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2504 Handle class_loader,
2505 TRAPS) {
2506 if (!class_loader.is_null() &&
2507 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2508 class_name != NULL) {
2509 ResourceMark rm(THREAD);
2510 char* name = class_name->as_C_string();
2511 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2512 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2513 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2514 name = pkg_name->as_C_string();
2515 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2516 StringUtils::replace_no_expand(name, "/", ".");
2517 const char* msg_text1 = "Class loader (instance of): ";
2518 const char* msg_text2 = " tried to load prohibited package name: ";
2519 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2520 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2521 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2522 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2523 }
2524 }
2525 return;
2526 }
2527
2528 // tell if two classes have the same enclosing class (at package level)
2529 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2530 if (class2 == this) return true;
2531 if (!class2->is_instance_klass()) return false;
2532
2533 // must be in same package before we try anything else
2534 if (!is_same_class_package(class2))
2535 return false;
2536
2537 // As long as there is an outer_this.getEnclosingClass,
2538 // shift the search outward.
2539 const InstanceKlass* outer_this = this;
2540 for (;;) {
2541 // As we walk along, look for equalities between outer_this and class2.
2542 // Eventually, the walks will terminate as outer_this stops
2543 // at the top-level class around the original class.
2544 bool ignore_inner_is_member;
2545 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2546 CHECK_false);
2547 if (next == NULL) break;
2548 if (next == class2) return true;
2549 outer_this = InstanceKlass::cast(next);
2550 }
2551
2552 // Now do the same for class2.
2553 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2554 for (;;) {
2555 bool ignore_inner_is_member;
2556 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2557 CHECK_false);
2558 if (next == NULL) break;
2559 // Might as well check the new outer against all available values.
2560 if (next == this) return true;
2561 if (next == outer_this) return true;
2562 outer2 = InstanceKlass::cast(next);
2563 }
2564
2565 // If by this point we have not found an equality between the
2566 // two classes, we know they are in separate package members.
2567 return false;
2568 }
2569
2570 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2571 constantPoolHandle i_cp(THREAD, constants());
2572 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2573 int ioff = iter.inner_class_info_index();
2574 if (ioff != 0) {
2575 // Check to see if the name matches the class we're looking for
2576 // before attempting to find the class.
2577 if (i_cp->klass_name_at_matches(this, ioff)) {
2578 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2579 if (this == inner_klass) {
2580 *ooff = iter.outer_class_info_index();
2581 *noff = iter.inner_name_index();
2582 return true;
2583 }
2584 }
2585 }
2586 }
2587 return false;
2588 }
2589
2590 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2591 InstanceKlass* outer_klass = NULL;
2592 *inner_is_member = false;
2593 int ooff = 0, noff = 0;
2594 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2595 if (has_inner_classes_attr) {
2596 constantPoolHandle i_cp(THREAD, constants());
2597 if (ooff != 0) {
2598 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2599 outer_klass = InstanceKlass::cast(ok);
2600 *inner_is_member = true;
2601 }
2602 if (NULL == outer_klass) {
2603 // It may be anonymous; try for that.
2604 int encl_method_class_idx = enclosing_method_class_index();
2605 if (encl_method_class_idx != 0) {
2606 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2607 outer_klass = InstanceKlass::cast(ok);
2608 *inner_is_member = false;
2609 }
2610 }
2611 }
2612
2613 // If no inner class attribute found for this class.
2614 if (NULL == outer_klass) return NULL;
2615
2616 // Throws an exception if outer klass has not declared k as an inner klass
2617 // We need evidence that each klass knows about the other, or else
2618 // the system could allow a spoof of an inner class to gain access rights.
2619 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2620 return outer_klass;
2621 }
2622
2623 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2624 jint access = access_flags().as_int();
2625
2626 // But check if it happens to be member class.
2627 InnerClassesIterator iter(this);
2628 for (; !iter.done(); iter.next()) {
2629 int ioff = iter.inner_class_info_index();
2630 // Inner class attribute can be zero, skip it.
2631 // Strange but true: JVM spec. allows null inner class refs.
2632 if (ioff == 0) continue;
2633
2634 // only look at classes that are already loaded
2635 // since we are looking for the flags for our self.
2636 Symbol* inner_name = constants()->klass_name_at(ioff);
2637 if (name() == inner_name) {
2638 // This is really a member class.
2639 access = iter.inner_access_flags();
2640 break;
2641 }
2642 }
2643 // Remember to strip ACC_SUPER bit
2644 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2645 }
2646
2647 jint InstanceKlass::jvmti_class_status() const {
2648 jint result = 0;
2649
2650 if (is_linked()) {
2651 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2652 }
2653
2654 if (is_initialized()) {
2655 assert(is_linked(), "Class status is not consistent");
2656 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2657 }
2658 if (is_in_error_state()) {
2659 result |= JVMTI_CLASS_STATUS_ERROR;
2660 }
2661 return result;
2662 }
2663
2664 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2665 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2666 int method_table_offset_in_words = ioe->offset()/wordSize;
2667 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2668 / itableOffsetEntry::size();
2669
2670 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2671 // If the interface isn't implemented by the receiver class,
2672 // the VM should throw IncompatibleClassChangeError.
2673 if (cnt >= nof_interfaces) {
2674 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2675 }
2676
2677 Klass* ik = ioe->interface_klass();
2678 if (ik == holder) break;
2679 }
2680
2681 itableMethodEntry* ime = ioe->first_method_entry(this);
2682 Method* m = ime[index].method();
2683 if (m == NULL) {
2684 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2685 }
2686 return m;
2687 }
2688
2689
2690 #if INCLUDE_JVMTI
2691 // update default_methods for redefineclasses for methods that are
2692 // not yet in the vtable due to concurrent subclass define and superinterface
2693 // redefinition
2694 // Note: those in the vtable, should have been updated via adjust_method_entries
2695 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2696 // search the default_methods for uses of either obsolete or EMCP methods
2697 if (default_methods() != NULL) {
2698 for (int index = 0; index < default_methods()->length(); index ++) {
2699 Method* old_method = default_methods()->at(index);
2700 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2701 continue; // skip uninteresting entries
2702 }
2703 assert(!old_method->is_deleted(), "default methods may not be deleted");
2704
2705 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2706
2707 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2708 assert(old_method != new_method, "sanity check");
2709
2710 default_methods()->at_put(index, new_method);
2711 if (log_is_enabled(Info, redefine, class, update)) {
2712 ResourceMark rm;
2713 if (!(*trace_name_printed)) {
2714 log_info(redefine, class, update)
2715 ("adjust: klassname=%s default methods from name=%s",
2716 external_name(), old_method->method_holder()->external_name());
2717 *trace_name_printed = true;
2718 }
2719 log_debug(redefine, class, update, vtables)
2720 ("default method update: %s(%s) ",
2721 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2722 }
2723 }
2724 }
2725 }
2726 #endif // INCLUDE_JVMTI
2727
2728 // On-stack replacement stuff
2729 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2730 // only one compilation can be active
2731 {
2732 // This is a short non-blocking critical region, so the no safepoint check is ok.
2733 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2734 assert(n->is_osr_method(), "wrong kind of nmethod");
2735 n->set_osr_link(osr_nmethods_head());
2736 set_osr_nmethods_head(n);
2737 // Raise the highest osr level if necessary
2738 if (TieredCompilation) {
2739 Method* m = n->method();
2740 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2741 }
2742 }
2743
2744 // Get rid of the osr methods for the same bci that have lower levels.
2745 if (TieredCompilation) {
2746 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2747 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2748 if (inv != NULL && inv->is_in_use()) {
2749 inv->make_not_entrant();
2750 }
2751 }
2752 }
2753 }
2754
2755 // Remove osr nmethod from the list. Return true if found and removed.
2756 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2757 // This is a short non-blocking critical region, so the no safepoint check is ok.
2758 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2759 assert(n->is_osr_method(), "wrong kind of nmethod");
2760 nmethod* last = NULL;
2761 nmethod* cur = osr_nmethods_head();
2762 int max_level = CompLevel_none; // Find the max comp level excluding n
2763 Method* m = n->method();
2764 // Search for match
2765 bool found = false;
2766 while(cur != NULL && cur != n) {
2767 if (TieredCompilation && m == cur->method()) {
2768 // Find max level before n
2769 max_level = MAX2(max_level, cur->comp_level());
2770 }
2771 last = cur;
2772 cur = cur->osr_link();
2773 }
2774 nmethod* next = NULL;
2775 if (cur == n) {
2776 found = true;
2777 next = cur->osr_link();
2778 if (last == NULL) {
2779 // Remove first element
2780 set_osr_nmethods_head(next);
2781 } else {
2782 last->set_osr_link(next);
2783 }
2784 }
2785 n->set_osr_link(NULL);
2786 if (TieredCompilation) {
2787 cur = next;
2788 while (cur != NULL) {
2789 // Find max level after n
2790 if (m == cur->method()) {
2791 max_level = MAX2(max_level, cur->comp_level());
2792 }
2793 cur = cur->osr_link();
2794 }
2795 m->set_highest_osr_comp_level(max_level);
2796 }
2797 return found;
2798 }
2799
2800 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2801 // This is a short non-blocking critical region, so the no safepoint check is ok.
2802 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2803 nmethod* osr = osr_nmethods_head();
2804 int found = 0;
2805 while (osr != NULL) {
2806 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2807 if (osr->method() == m) {
2808 osr->mark_for_deoptimization();
2809 found++;
2810 }
2811 osr = osr->osr_link();
2812 }
2813 return found;
2814 }
2815
2816 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2817 // This is a short non-blocking critical region, so the no safepoint check is ok.
2818 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2819 nmethod* osr = osr_nmethods_head();
2820 nmethod* best = NULL;
2821 while (osr != NULL) {
2822 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2823 // There can be a time when a c1 osr method exists but we are waiting
2824 // for a c2 version. When c2 completes its osr nmethod we will trash
2825 // the c1 version and only be able to find the c2 version. However
2826 // while we overflow in the c1 code at back branches we don't want to
2827 // try and switch to the same code as we are already running
2828
2829 if (osr->method() == m &&
2830 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2831 if (match_level) {
2832 if (osr->comp_level() == comp_level) {
2833 // Found a match - return it.
2834 return osr;
2835 }
2836 } else {
2837 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2838 if (osr->comp_level() == CompLevel_highest_tier) {
2839 // Found the best possible - return it.
2840 return osr;
2841 }
2842 best = osr;
2843 }
2844 }
2845 }
2846 osr = osr->osr_link();
2847 }
2848 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2849 return best;
2850 }
2851 return NULL;
2852 }
2853
2854 // -----------------------------------------------------------------------------------------------------
2855 // Printing
2856
2857 #ifndef PRODUCT
2858
2859 #define BULLET " - "
2860
2861 static const char* state_names[] = {
2862 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2863 };
2864
2865 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2866 for (int i = 0; i < len; i++) {
2867 intptr_t e = start[i];
2868 st->print("%d : " INTPTR_FORMAT, i, e);
2869 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2870 st->print(" ");
2871 ((Metadata*)e)->print_value_on(st);
2872 }
2873 st->cr();
2874 }
2875 }
2876
2877 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2878 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
2879 }
2880
2881 void InstanceKlass::print_on(outputStream* st) const {
2882 assert(is_klass(), "must be klass");
2883 Klass::print_on(st);
2884
2885 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2886 st->print(BULLET"klass size: %d", size()); st->cr();
2887 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2888 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2889 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2890 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2891 st->print(BULLET"sub: ");
2892 Klass* sub = subklass();
2893 int n;
2894 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2895 if (n < MaxSubklassPrintSize) {
2896 sub->print_value_on(st);
2897 st->print(" ");
2898 }
2899 }
2900 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2901 st->cr();
2902
2903 if (is_interface()) {
2904 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2905 if (nof_implementors() == 1) {
2906 st->print_cr(BULLET"implementor: ");
2907 st->print(" ");
2908 implementor()->print_value_on(st);
2909 st->cr();
2910 }
2911 }
2912
2913 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2914 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2915 if (Verbose || WizardMode) {
2916 Array<Method*>* method_array = methods();
2917 for (int i = 0; i < method_array->length(); i++) {
2918 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2919 }
2920 }
2921 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2922 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2923 if (Verbose && default_methods() != NULL) {
2924 Array<Method*>* method_array = default_methods();
2925 for (int i = 0; i < method_array->length(); i++) {
2926 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2927 }
2928 }
2929 if (default_vtable_indices() != NULL) {
2930 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2931 }
2932 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2933 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2934 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2935 if (class_loader_data() != NULL) {
2936 st->print(BULLET"class loader data: ");
2937 class_loader_data()->print_value_on(st);
2938 st->cr();
2939 }
2940 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2941 if (source_file_name() != NULL) {
2942 st->print(BULLET"source file: ");
2943 source_file_name()->print_value_on(st);
2944 st->cr();
2945 }
2946 if (source_debug_extension() != NULL) {
2947 st->print(BULLET"source debug extension: ");
2948 st->print("%s", source_debug_extension());
2949 st->cr();
2950 }
2951 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2952 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2953 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2954 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2955 {
2956 bool have_pv = false;
2957 // previous versions are linked together through the InstanceKlass
2958 for (InstanceKlass* pv_node = previous_versions();
2959 pv_node != NULL;
2960 pv_node = pv_node->previous_versions()) {
2961 if (!have_pv)
2962 st->print(BULLET"previous version: ");
2963 have_pv = true;
2964 pv_node->constants()->print_value_on(st);
2965 }
2966 if (have_pv) st->cr();
2967 }
2968
2969 if (generic_signature() != NULL) {
2970 st->print(BULLET"generic signature: ");
2971 generic_signature()->print_value_on(st);
2972 st->cr();
2973 }
2974 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2975 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2976 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2977 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2978 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2979 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2980 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2981 FieldPrinter print_static_field(st);
2982 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2983 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2984 FieldPrinter print_nonstatic_field(st);
2985 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2986 ik->do_nonstatic_fields(&print_nonstatic_field);
2987
2988 st->print(BULLET"non-static oop maps: ");
2989 OopMapBlock* map = start_of_nonstatic_oop_maps();
2990 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2991 while (map < end_map) {
2992 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2993 map++;
2994 }
2995 st->cr();
2996 }
2997
2998 #endif //PRODUCT
2999
3000 void InstanceKlass::print_value_on(outputStream* st) const {
3001 assert(is_klass(), "must be klass");
3002 if (Verbose || WizardMode) access_flags().print_on(st);
3003 name()->print_value_on(st);
3004 }
3005
3006 #ifndef PRODUCT
3007
3008 void FieldPrinter::do_field(fieldDescriptor* fd) {
3009 _st->print(BULLET);
3010 if (_obj == NULL) {
3011 fd->print_on(_st);
3012 _st->cr();
3013 } else {
3014 fd->print_on_for(_st, _obj);
3015 _st->cr();
3016 }
3017 }
3018
3019
3020 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3021 Klass::oop_print_on(obj, st);
3022
3023 if (this == SystemDictionary::String_klass()) {
3024 typeArrayOop value = java_lang_String::value(obj);
3025 juint length = java_lang_String::length(obj);
3026 if (value != NULL &&
3027 value->is_typeArray() &&
3028 length <= (juint) value->length()) {
3029 st->print(BULLET"string: ");
3030 java_lang_String::print(obj, st);
3031 st->cr();
3032 if (!WizardMode) return; // that is enough
3033 }
3034 }
3035
3036 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3037 FieldPrinter print_field(st, obj);
3038 do_nonstatic_fields(&print_field);
3039
3040 if (this == SystemDictionary::Class_klass()) {
3041 st->print(BULLET"signature: ");
3042 java_lang_Class::print_signature(obj, st);
3043 st->cr();
3044 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3045 st->print(BULLET"fake entry for mirror: ");
3046 mirrored_klass->print_value_on_maybe_null(st);
3047 st->cr();
3048 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3049 st->print(BULLET"fake entry for array: ");
3050 array_klass->print_value_on_maybe_null(st);
3051 st->cr();
3052 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3053 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3054 Klass* real_klass = java_lang_Class::as_Klass(obj);
3055 if (real_klass != NULL && real_klass->is_instance_klass()) {
3056 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3057 }
3058 } else if (this == SystemDictionary::MethodType_klass()) {
3059 st->print(BULLET"signature: ");
3060 java_lang_invoke_MethodType::print_signature(obj, st);
3061 st->cr();
3062 }
3063 }
3064
3065 #endif //PRODUCT
3066
3067 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3068 st->print("a ");
3069 name()->print_value_on(st);
3070 obj->print_address_on(st);
3071 if (this == SystemDictionary::String_klass()
3072 && java_lang_String::value(obj) != NULL) {
3073 ResourceMark rm;
3074 int len = java_lang_String::length(obj);
3075 int plen = (len < 24 ? len : 12);
3076 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3077 st->print(" = \"%s\"", str);
3078 if (len > plen)
3079 st->print("...[%d]", len);
3080 } else if (this == SystemDictionary::Class_klass()) {
3081 Klass* k = java_lang_Class::as_Klass(obj);
3082 st->print(" = ");
3083 if (k != NULL) {
3084 k->print_value_on(st);
3085 } else {
3086 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3087 st->print("%s", tname ? tname : "type?");
3088 }
3089 } else if (this == SystemDictionary::MethodType_klass()) {
3090 st->print(" = ");
3091 java_lang_invoke_MethodType::print_signature(obj, st);
3092 } else if (java_lang_boxing_object::is_instance(obj)) {
3093 st->print(" = ");
3094 java_lang_boxing_object::print(obj, st);
3095 } else if (this == SystemDictionary::LambdaForm_klass()) {
3096 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3097 if (vmentry != NULL) {
3098 st->print(" => ");
3099 vmentry->print_value_on(st);
3100 }
3101 } else if (this == SystemDictionary::MemberName_klass()) {
3102 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3103 if (vmtarget != NULL) {
3104 st->print(" = ");
3105 vmtarget->print_value_on(st);
3106 } else {
3107 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3108 st->print(".");
3109 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3110 }
3111 }
3112 }
3113
3114 const char* InstanceKlass::internal_name() const {
3115 return external_name();
3116 }
3117
3118 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3119 const char* module_name,
3120 const ClassFileStream* cfs) const {
3121 if (!log_is_enabled(Info, class, load)) {
3122 return;
3123 }
3124
3125 ResourceMark rm;
3126 LogMessage(class, load) msg;
3127 stringStream info_stream;
3128
3129 // Name and class hierarchy info
3130 info_stream.print("%s", external_name());
3131
3132 // Source
3133 if (cfs != NULL) {
3134 if (cfs->source() != NULL) {
3135 if (module_name != NULL) {
3136 if (ClassLoader::is_modules_image(cfs->source())) {
3137 info_stream.print(" source: jrt:/%s", module_name);
3138 } else {
3139 info_stream.print(" source: %s", cfs->source());
3140 }
3141 } else {
3142 info_stream.print(" source: %s", cfs->source());
3143 }
3144 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3145 Thread* THREAD = Thread::current();
3146 Klass* caller =
3147 THREAD->is_Java_thread()
3148 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3149 : NULL;
3150 // caller can be NULL, for example, during a JVMTI VM_Init hook
3151 if (caller != NULL) {
3152 info_stream.print(" source: instance of %s", caller->external_name());
3153 } else {
3154 // source is unknown
3155 }
3156 } else {
3157 oop class_loader = loader_data->class_loader();
3158 info_stream.print(" source: %s", class_loader->klass()->external_name());
3159 }
3160 } else {
3161 info_stream.print(" source: shared objects file");
3162 }
3163
3164 msg.info("%s", info_stream.as_string());
3165
3166 if (log_is_enabled(Debug, class, load)) {
3167 stringStream debug_stream;
3168
3169 // Class hierarchy info
3170 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3171 p2i(this), p2i(superklass()));
3172
3173 // Interfaces
3174 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3175 debug_stream.print(" interfaces:");
3176 int length = local_interfaces()->length();
3177 for (int i = 0; i < length; i++) {
3178 debug_stream.print(" " INTPTR_FORMAT,
3179 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3180 }
3181 }
3182
3183 // Class loader
3184 debug_stream.print(" loader: [");
3185 loader_data->print_value_on(&debug_stream);
3186 debug_stream.print("]");
3187
3188 // Classfile checksum
3189 if (cfs) {
3190 debug_stream.print(" bytes: %d checksum: %08x",
3191 cfs->length(),
3192 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3193 cfs->length()));
3194 }
3195
3196 msg.debug("%s", debug_stream.as_string());
3197 }
3198 }
3199
3200 #if INCLUDE_SERVICES
3201 // Size Statistics
3202 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3203 Klass::collect_statistics(sz);
3204
3205 sz->_inst_size = wordSize * size_helper();
3206 sz->_vtab_bytes = wordSize * vtable_length();
3207 sz->_itab_bytes = wordSize * itable_length();
3208 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3209
3210 int n = 0;
3211 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3212 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3213 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3214 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3215 n += (sz->_fields_bytes = sz->count_array(fields()));
3216 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3217 sz->_ro_bytes += n;
3218
3219 const ConstantPool* cp = constants();
3220 if (cp) {
3221 cp->collect_statistics(sz);
3222 }
3223
3224 const Annotations* anno = annotations();
3225 if (anno) {
3226 anno->collect_statistics(sz);
3227 }
3228
3229 const Array<Method*>* methods_array = methods();
3230 if (methods()) {
3231 for (int i = 0; i < methods_array->length(); i++) {
3232 Method* method = methods_array->at(i);
3233 if (method) {
3234 sz->_method_count ++;
3235 method->collect_statistics(sz);
3236 }
3237 }
3238 }
3239 }
3240 #endif // INCLUDE_SERVICES
3241
3242 // Verification
3243
3244 class VerifyFieldClosure: public OopClosure {
3245 protected:
3246 template <class T> void do_oop_work(T* p) {
3247 oop obj = RawAccess<>::oop_load(p);
3248 if (!oopDesc::is_oop_or_null(obj)) {
3249 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3250 Universe::print_on(tty);
3251 guarantee(false, "boom");
3252 }
3253 }
3254 public:
3255 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3256 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3257 };
3258
3259 void InstanceKlass::verify_on(outputStream* st) {
3260 #ifndef PRODUCT
3261 // Avoid redundant verifies, this really should be in product.
3262 if (_verify_count == Universe::verify_count()) return;
3263 _verify_count = Universe::verify_count();
3264 #endif
3265
3266 // Verify Klass
3267 Klass::verify_on(st);
3268
3269 // Verify that klass is present in ClassLoaderData
3270 guarantee(class_loader_data()->contains_klass(this),
3271 "this class isn't found in class loader data");
3272
3273 // Verify vtables
3274 if (is_linked()) {
3275 // $$$ This used to be done only for m/s collections. Doing it
3276 // always seemed a valid generalization. (DLD -- 6/00)
3277 vtable().verify(st);
3278 }
3279
3280 // Verify first subklass
3281 if (subklass() != NULL) {
3282 guarantee(subklass()->is_klass(), "should be klass");
3283 }
3284
3285 // Verify siblings
3286 Klass* super = this->super();
3287 Klass* sib = next_sibling();
3288 if (sib != NULL) {
3289 if (sib == this) {
3290 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3291 }
3292
3293 guarantee(sib->is_klass(), "should be klass");
3294 guarantee(sib->super() == super, "siblings should have same superklass");
3295 }
3296
3297 // Verify implementor fields
3298 Klass* im = implementor();
3299 if (im != NULL) {
3300 guarantee(is_interface(), "only interfaces should have implementor set");
3301 guarantee(im->is_klass(), "should be klass");
3302 guarantee(!im->is_interface() || im == this,
3303 "implementors cannot be interfaces");
3304 }
3305
3306 // Verify local interfaces
3307 if (local_interfaces()) {
3308 Array<Klass*>* local_interfaces = this->local_interfaces();
3309 for (int j = 0; j < local_interfaces->length(); j++) {
3310 Klass* e = local_interfaces->at(j);
3311 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3312 }
3313 }
3314
3315 // Verify transitive interfaces
3316 if (transitive_interfaces() != NULL) {
3317 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3318 for (int j = 0; j < transitive_interfaces->length(); j++) {
3319 Klass* e = transitive_interfaces->at(j);
3320 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3321 }
3322 }
3323
3324 // Verify methods
3325 if (methods() != NULL) {
3326 Array<Method*>* methods = this->methods();
3327 for (int j = 0; j < methods->length(); j++) {
3328 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3329 }
3330 for (int j = 0; j < methods->length() - 1; j++) {
3331 Method* m1 = methods->at(j);
3332 Method* m2 = methods->at(j + 1);
3333 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3334 }
3335 }
3336
3337 // Verify method ordering
3338 if (method_ordering() != NULL) {
3339 Array<int>* method_ordering = this->method_ordering();
3340 int length = method_ordering->length();
3341 if (JvmtiExport::can_maintain_original_method_order() ||
3342 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3343 guarantee(length == methods()->length(), "invalid method ordering length");
3344 jlong sum = 0;
3345 for (int j = 0; j < length; j++) {
3346 int original_index = method_ordering->at(j);
3347 guarantee(original_index >= 0, "invalid method ordering index");
3348 guarantee(original_index < length, "invalid method ordering index");
3349 sum += original_index;
3350 }
3351 // Verify sum of indices 0,1,...,length-1
3352 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3353 } else {
3354 guarantee(length == 0, "invalid method ordering length");
3355 }
3356 }
3357
3358 // Verify default methods
3359 if (default_methods() != NULL) {
3360 Array<Method*>* methods = this->default_methods();
3361 for (int j = 0; j < methods->length(); j++) {
3362 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3363 }
3364 for (int j = 0; j < methods->length() - 1; j++) {
3365 Method* m1 = methods->at(j);
3366 Method* m2 = methods->at(j + 1);
3367 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3368 }
3369 }
3370
3371 // Verify JNI static field identifiers
3372 if (jni_ids() != NULL) {
3373 jni_ids()->verify(this);
3374 }
3375
3376 // Verify other fields
3377 if (array_klasses() != NULL) {
3378 guarantee(array_klasses()->is_klass(), "should be klass");
3379 }
3380 if (constants() != NULL) {
3381 guarantee(constants()->is_constantPool(), "should be constant pool");
3382 }
3383 const Klass* host = host_klass();
3384 if (host != NULL) {
3385 guarantee(host->is_klass(), "should be klass");
3386 }
3387 }
3388
3389 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3390 Klass::oop_verify_on(obj, st);
3391 VerifyFieldClosure blk;
3392 obj->oop_iterate_no_header(&blk);
3393 }
3394
3395
3396 // JNIid class for jfieldIDs only
3397 // Note to reviewers:
3398 // These JNI functions are just moved over to column 1 and not changed
3399 // in the compressed oops workspace.
3400 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3401 _holder = holder;
3402 _offset = offset;
3403 _next = next;
3404 debug_only(_is_static_field_id = false;)
3405 }
3406
3407
3408 JNIid* JNIid::find(int offset) {
3409 JNIid* current = this;
3410 while (current != NULL) {
3411 if (current->offset() == offset) return current;
3412 current = current->next();
3413 }
3414 return NULL;
3415 }
3416
3417 void JNIid::deallocate(JNIid* current) {
3418 while (current != NULL) {
3419 JNIid* next = current->next();
3420 delete current;
3421 current = next;
3422 }
3423 }
3424
3425
3426 void JNIid::verify(Klass* holder) {
3427 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3428 int end_field_offset;
3429 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3430
3431 JNIid* current = this;
3432 while (current != NULL) {
3433 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3434 #ifdef ASSERT
3435 int o = current->offset();
3436 if (current->is_static_field_id()) {
3437 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3438 }
3439 #endif
3440 current = current->next();
3441 }
3442 }
3443
3444 oop InstanceKlass::holder_phantom() const {
3445 return class_loader_data()->holder_phantom();
3446 }
3447
3448 #ifdef ASSERT
3449 void InstanceKlass::set_init_state(ClassState state) {
3450 bool good_state = is_shared() ? (_init_state <= state)
3451 : (_init_state < state);
3452 assert(good_state || state == allocated, "illegal state transition");
3453 _init_state = (u1)state;
3454 }
3455 #endif
3456
3457 #if INCLUDE_JVMTI
3458
3459 // RedefineClasses() support for previous versions
3460
3461 // Globally, there is at least one previous version of a class to walk
3462 // during class unloading, which is saved because old methods in the class
3463 // are still running. Otherwise the previous version list is cleaned up.
3464 bool InstanceKlass::_has_previous_versions = false;
3465
3466 // Returns true if there are previous versions of a class for class
3467 // unloading only. Also resets the flag to false. purge_previous_version
3468 // will set the flag to true if there are any left, i.e., if there's any
3469 // work to do for next time. This is to avoid the expensive code cache
3470 // walk in CLDG::do_unloading().
3471 bool InstanceKlass::has_previous_versions_and_reset() {
3472 bool ret = _has_previous_versions;
3473 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3474 ret ? "true" : "false");
3475 _has_previous_versions = false;
3476 return ret;
3477 }
3478
3479 // Purge previous versions before adding new previous versions of the class and
3480 // during class unloading.
3481 void InstanceKlass::purge_previous_version_list() {
3482 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3483 assert(has_been_redefined(), "Should only be called for main class");
3484
3485 // Quick exit.
3486 if (previous_versions() == NULL) {
3487 return;
3488 }
3489
3490 // This klass has previous versions so see what we can cleanup
3491 // while it is safe to do so.
3492
3493 int deleted_count = 0; // leave debugging breadcrumbs
3494 int live_count = 0;
3495 ClassLoaderData* loader_data = class_loader_data();
3496 assert(loader_data != NULL, "should never be null");
3497
3498 ResourceMark rm;
3499 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3500
3501 // previous versions are linked together through the InstanceKlass
3502 InstanceKlass* pv_node = previous_versions();
3503 InstanceKlass* last = this;
3504 int version = 0;
3505
3506 // check the previous versions list
3507 for (; pv_node != NULL; ) {
3508
3509 ConstantPool* pvcp = pv_node->constants();
3510 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3511
3512 if (!pvcp->on_stack()) {
3513 // If the constant pool isn't on stack, none of the methods
3514 // are executing. Unlink this previous_version.
3515 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3516 // so will be deallocated during the next phase of class unloading.
3517 log_trace(redefine, class, iklass, purge)
3518 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3519 // For debugging purposes.
3520 pv_node->set_is_scratch_class();
3521 // Unlink from previous version list.
3522 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3523 InstanceKlass* next = pv_node->previous_versions();
3524 pv_node->link_previous_versions(NULL); // point next to NULL
3525 last->link_previous_versions(next);
3526 // Add to the deallocate list after unlinking
3527 loader_data->add_to_deallocate_list(pv_node);
3528 pv_node = next;
3529 deleted_count++;
3530 version++;
3531 continue;
3532 } else {
3533 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3534 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3535 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3536 live_count++;
3537 // found a previous version for next time we do class unloading
3538 _has_previous_versions = true;
3539 }
3540
3541 // At least one method is live in this previous version.
3542 // Reset dead EMCP methods not to get breakpoints.
3543 // All methods are deallocated when all of the methods for this class are no
3544 // longer running.
3545 Array<Method*>* method_refs = pv_node->methods();
3546 if (method_refs != NULL) {
3547 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3548 for (int j = 0; j < method_refs->length(); j++) {
3549 Method* method = method_refs->at(j);
3550
3551 if (!method->on_stack()) {
3552 // no breakpoints for non-running methods
3553 if (method->is_running_emcp()) {
3554 method->set_running_emcp(false);
3555 }
3556 } else {
3557 assert (method->is_obsolete() || method->is_running_emcp(),
3558 "emcp method cannot run after emcp bit is cleared");
3559 log_trace(redefine, class, iklass, purge)
3560 ("purge: %s(%s): prev method @%d in version @%d is alive",
3561 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3562 }
3563 }
3564 }
3565 // next previous version
3566 last = pv_node;
3567 pv_node = pv_node->previous_versions();
3568 version++;
3569 }
3570 log_trace(redefine, class, iklass, purge)
3571 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3572 }
3573
3574 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3575 int emcp_method_count) {
3576 int obsolete_method_count = old_methods->length() - emcp_method_count;
3577
3578 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3579 _previous_versions != NULL) {
3580 // We have a mix of obsolete and EMCP methods so we have to
3581 // clear out any matching EMCP method entries the hard way.
3582 int local_count = 0;
3583 for (int i = 0; i < old_methods->length(); i++) {
3584 Method* old_method = old_methods->at(i);
3585 if (old_method->is_obsolete()) {
3586 // only obsolete methods are interesting
3587 Symbol* m_name = old_method->name();
3588 Symbol* m_signature = old_method->signature();
3589
3590 // previous versions are linked together through the InstanceKlass
3591 int j = 0;
3592 for (InstanceKlass* prev_version = _previous_versions;
3593 prev_version != NULL;
3594 prev_version = prev_version->previous_versions(), j++) {
3595
3596 Array<Method*>* method_refs = prev_version->methods();
3597 for (int k = 0; k < method_refs->length(); k++) {
3598 Method* method = method_refs->at(k);
3599
3600 if (!method->is_obsolete() &&
3601 method->name() == m_name &&
3602 method->signature() == m_signature) {
3603 // The current RedefineClasses() call has made all EMCP
3604 // versions of this method obsolete so mark it as obsolete
3605 log_trace(redefine, class, iklass, add)
3606 ("%s(%s): flush obsolete method @%d in version @%d",
3607 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3608
3609 method->set_is_obsolete();
3610 break;
3611 }
3612 }
3613
3614 // The previous loop may not find a matching EMCP method, but
3615 // that doesn't mean that we can optimize and not go any
3616 // further back in the PreviousVersion generations. The EMCP
3617 // method for this generation could have already been made obsolete,
3618 // but there still may be an older EMCP method that has not
3619 // been made obsolete.
3620 }
3621
3622 if (++local_count >= obsolete_method_count) {
3623 // no more obsolete methods so bail out now
3624 break;
3625 }
3626 }
3627 }
3628 }
3629 }
3630
3631 // Save the scratch_class as the previous version if any of the methods are running.
3632 // The previous_versions are used to set breakpoints in EMCP methods and they are
3633 // also used to clean MethodData links to redefined methods that are no longer running.
3634 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3635 int emcp_method_count) {
3636 assert(Thread::current()->is_VM_thread(),
3637 "only VMThread can add previous versions");
3638
3639 ResourceMark rm;
3640 log_trace(redefine, class, iklass, add)
3641 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3642
3643 // Clean out old previous versions for this class
3644 purge_previous_version_list();
3645
3646 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3647 // a previous redefinition may be made obsolete by this redefinition.
3648 Array<Method*>* old_methods = scratch_class->methods();
3649 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3650
3651 // If the constant pool for this previous version of the class
3652 // is not marked as being on the stack, then none of the methods
3653 // in this previous version of the class are on the stack so
3654 // we don't need to add this as a previous version.
3655 ConstantPool* cp_ref = scratch_class->constants();
3656 if (!cp_ref->on_stack()) {
3657 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3658 // For debugging purposes.
3659 scratch_class->set_is_scratch_class();
3660 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3661 return;
3662 }
3663
3664 if (emcp_method_count != 0) {
3665 // At least one method is still running, check for EMCP methods
3666 for (int i = 0; i < old_methods->length(); i++) {
3667 Method* old_method = old_methods->at(i);
3668 if (!old_method->is_obsolete() && old_method->on_stack()) {
3669 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3670 // we can add breakpoints for it.
3671
3672 // We set the method->on_stack bit during safepoints for class redefinition
3673 // and use this bit to set the is_running_emcp bit.
3674 // After the safepoint, the on_stack bit is cleared and the running emcp
3675 // method may exit. If so, we would set a breakpoint in a method that
3676 // is never reached, but this won't be noticeable to the programmer.
3677 old_method->set_running_emcp(true);
3678 log_trace(redefine, class, iklass, add)
3679 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3680 } else if (!old_method->is_obsolete()) {
3681 log_trace(redefine, class, iklass, add)
3682 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3683 }
3684 }
3685 }
3686
3687 // Add previous version if any methods are still running.
3688 // Set has_previous_version flag for processing during class unloading.
3689 _has_previous_versions = true;
3690 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3691 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3692 scratch_class->link_previous_versions(previous_versions());
3693 link_previous_versions(scratch_class);
3694 } // end add_previous_version()
3695
3696 #endif // INCLUDE_JVMTI
3697
3698 Method* InstanceKlass::method_with_idnum(int idnum) {
3699 Method* m = NULL;
3700 if (idnum < methods()->length()) {
3701 m = methods()->at(idnum);
3702 }
3703 if (m == NULL || m->method_idnum() != idnum) {
3704 for (int index = 0; index < methods()->length(); ++index) {
3705 m = methods()->at(index);
3706 if (m->method_idnum() == idnum) {
3707 return m;
3708 }
3709 }
3710 // None found, return null for the caller to handle.
3711 return NULL;
3712 }
3713 return m;
3714 }
3715
3716
3717 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3718 if (idnum >= methods()->length()) {
3719 return NULL;
3720 }
3721 Method* m = methods()->at(idnum);
3722 if (m != NULL && m->orig_method_idnum() == idnum) {
3723 return m;
3724 }
3725 // Obsolete method idnum does not match the original idnum
3726 for (int index = 0; index < methods()->length(); ++index) {
3727 m = methods()->at(index);
3728 if (m->orig_method_idnum() == idnum) {
3729 return m;
3730 }
3731 }
3732 // None found, return null for the caller to handle.
3733 return NULL;
3734 }
3735
3736
3737 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3738 InstanceKlass* holder = get_klass_version(version);
3739 if (holder == NULL) {
3740 return NULL; // The version of klass is gone, no method is found
3741 }
3742 Method* method = holder->method_with_orig_idnum(idnum);
3743 return method;
3744 }
3745
3746 #if INCLUDE_JVMTI
3747 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3748 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3749 // Ignore the archived class stream data
3750 return NULL;
3751 } else {
3752 return _cached_class_file;
3753 }
3754 }
3755
3756 jint InstanceKlass::get_cached_class_file_len() {
3757 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3758 }
3759
3760 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3761 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3762 }
3763
3764 #if INCLUDE_CDS
3765 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3766 if (DumpSharedSpaces) {
3767 return _cached_class_file;
3768 } else {
3769 assert(this->is_shared(), "class should be shared");
3770 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3771 return _cached_class_file;
3772 } else {
3773 return NULL;
3774 }
3775 }
3776 }
3777 #endif
3778 #endif