1 /*
2 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classFileParser.hpp"
27 #include "classfile/classFileStream.hpp"
28 #include "classfile/classLoader.hpp"
29 #include "classfile/javaClasses.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/systemDictionaryShared.hpp"
32 #include "classfile/verifier.hpp"
33 #include "classfile/vmSymbols.hpp"
34 #include "code/dependencyContext.hpp"
35 #include "compiler/compileBroker.hpp"
36 #include "gc/shared/collectedHeap.inline.hpp"
37 #include "gc/shared/specialized_oop_closures.hpp"
38 #include "interpreter/oopMapCache.hpp"
39 #include "interpreter/rewriter.hpp"
40 #include "jvmtifiles/jvmti.h"
41 #include "logging/log.hpp"
42 #include "memory/heapInspection.hpp"
43 #include "memory/iterator.inline.hpp"
44 #include "memory/metadataFactory.hpp"
45 #include "memory/metaspaceShared.hpp"
46 #include "memory/oopFactory.hpp"
47 #include "memory/resourceArea.hpp"
48 #include "oops/fieldStreams.hpp"
49 #include "oops/instanceClassLoaderKlass.hpp"
50 #include "oops/instanceKlass.inline.hpp"
51 #include "oops/instanceMirrorKlass.hpp"
52 #include "oops/instanceOop.hpp"
53 #include "oops/klass.inline.hpp"
54 #include "oops/method.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "oops/symbol.hpp"
57 #include "prims/jvmtiExport.hpp"
58 #include "prims/jvmtiRedefineClasses.hpp"
59 #include "prims/jvmtiThreadState.hpp"
60 #include "prims/methodComparator.hpp"
61 #include "aot/aotLoader.hpp"
62 #include "runtime/atomic.hpp"
63 #include "runtime/fieldDescriptor.hpp"
64 #include "runtime/handles.inline.hpp"
65 #include "runtime/javaCalls.hpp"
66 #include "runtime/mutexLocker.hpp"
67 #include "runtime/orderAccess.inline.hpp"
68 #include "runtime/thread.inline.hpp"
69 #include "services/classLoadingService.hpp"
70 #include "services/threadService.hpp"
71 #include "utilities/dtrace.hpp"
72 #include "utilities/macros.hpp"
73 #include "utilities/stringUtils.hpp"
74 #include "logging/log.hpp"
75 #ifdef COMPILER1
76 #include "c1/c1_Compiler.hpp"
77 #endif
78
79 #ifdef DTRACE_ENABLED
80
81
82 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
83 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
84 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
85 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
86 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
87 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
88 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
89 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
90 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
91 { \
92 char* data = NULL; \
93 int len = 0; \
94 Symbol* name = (clss)->name(); \
95 if (name != NULL) { \
96 data = (char*)name->bytes(); \
97 len = name->utf8_length(); \
98 } \
99 HOTSPOT_CLASS_INITIALIZATION_##type( \
100 data, len, (clss)->class_loader(), thread_type); \
101 }
102
103 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
104 { \
105 char* data = NULL; \
106 int len = 0; \
107 Symbol* name = (clss)->name(); \
108 if (name != NULL) { \
109 data = (char*)name->bytes(); \
110 len = name->utf8_length(); \
111 } \
112 HOTSPOT_CLASS_INITIALIZATION_##type( \
113 data, len, (clss)->class_loader(), thread_type, wait); \
114 }
115
116 #else // ndef DTRACE_ENABLED
117
118 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
119 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
120
121 #endif // ndef DTRACE_ENABLED
122
123 volatile int InstanceKlass::_total_instanceKlass_count = 0;
124
125 static inline bool is_class_loader(const Symbol* class_name,
126 const ClassFileParser& parser) {
127 assert(class_name != NULL, "invariant");
128
129 if (class_name == vmSymbols::java_lang_ClassLoader()) {
130 return true;
131 }
132
133 if (SystemDictionary::ClassLoader_klass_loaded()) {
134 const Klass* const super_klass = parser.super_klass();
135 if (super_klass != NULL) {
136 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
137 return true;
138 }
139 }
140 }
141 return false;
142 }
143
144 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
145 const int size = InstanceKlass::size(parser.vtable_size(),
146 parser.itable_size(),
147 nonstatic_oop_map_size(parser.total_oop_map_count()),
148 parser.is_interface(),
149 parser.is_anonymous(),
150 should_store_fingerprint());
151
152 const Symbol* const class_name = parser.class_name();
153 assert(class_name != NULL, "invariant");
154 ClassLoaderData* loader_data = parser.loader_data();
155 assert(loader_data != NULL, "invariant");
156
157 InstanceKlass* ik;
158
159 // Allocation
160 if (REF_NONE == parser.reference_type()) {
161 if (class_name == vmSymbols::java_lang_Class()) {
162 // mirror
163 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
164 }
165 else if (is_class_loader(class_name, parser)) {
166 // class loader
167 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
168 }
169 else {
170 // normal
171 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
172 }
173 }
174 else {
175 // reference
176 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
177 }
178
179 // Check for pending exception before adding to the loader data and incrementing
180 // class count. Can get OOM here.
181 if (HAS_PENDING_EXCEPTION) {
182 return NULL;
183 }
184
185 assert(ik != NULL, "invariant");
186
187 const bool publicize = !parser.is_internal();
188
189 // Add all classes to our internal class loader list here,
190 // including classes in the bootstrap (NULL) class loader.
191 loader_data->add_class(ik, publicize);
192 Atomic::inc(&_total_instanceKlass_count);
193
194 return ik;
195 }
196
197
198 // copy method ordering from resource area to Metaspace
199 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
200 if (m != NULL) {
201 // allocate a new array and copy contents (memcpy?)
202 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
203 for (int i = 0; i < m->length(); i++) {
204 _method_ordering->at_put(i, m->at(i));
205 }
206 } else {
207 _method_ordering = Universe::the_empty_int_array();
208 }
209 }
210
211 // create a new array of vtable_indices for default methods
212 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
213 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
214 assert(default_vtable_indices() == NULL, "only create once");
215 set_default_vtable_indices(vtable_indices);
216 return vtable_indices;
217 }
218
219 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
220 _static_field_size(parser.static_field_size()),
221 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
222 _itable_len(parser.itable_size()),
223 _reference_type(parser.reference_type()) {
224 set_vtable_length(parser.vtable_size());
225 set_kind(kind);
226 set_access_flags(parser.access_flags());
227 set_is_anonymous(parser.is_anonymous());
228 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
229 false));
230
231 assert(NULL == _methods, "underlying memory not zeroed?");
232 assert(is_instance_klass(), "is layout incorrect?");
233 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
234 }
235
236 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
237 Array<Method*>* methods) {
238 if (methods != NULL && methods != Universe::the_empty_method_array() &&
239 !methods->is_shared()) {
240 for (int i = 0; i < methods->length(); i++) {
241 Method* method = methods->at(i);
242 if (method == NULL) continue; // maybe null if error processing
243 // Only want to delete methods that are not executing for RedefineClasses.
244 // The previous version will point to them so they're not totally dangling
245 assert (!method->on_stack(), "shouldn't be called with methods on stack");
246 MetadataFactory::free_metadata(loader_data, method);
247 }
248 MetadataFactory::free_array<Method*>(loader_data, methods);
249 }
250 }
251
252 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
253 const Klass* super_klass,
254 Array<Klass*>* local_interfaces,
255 Array<Klass*>* transitive_interfaces) {
256 // Only deallocate transitive interfaces if not empty, same as super class
257 // or same as local interfaces. See code in parseClassFile.
258 Array<Klass*>* ti = transitive_interfaces;
259 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
260 // check that the interfaces don't come from super class
261 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
262 InstanceKlass::cast(super_klass)->transitive_interfaces();
263 if (ti != sti && ti != NULL && !ti->is_shared()) {
264 MetadataFactory::free_array<Klass*>(loader_data, ti);
265 }
266 }
267
268 // local interfaces can be empty
269 if (local_interfaces != Universe::the_empty_klass_array() &&
270 local_interfaces != NULL && !local_interfaces->is_shared()) {
271 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
272 }
273 }
274
275 // This function deallocates the metadata and C heap pointers that the
276 // InstanceKlass points to.
277 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
278
279 // Orphan the mirror first, CMS thinks it's still live.
280 if (java_mirror() != NULL) {
281 java_lang_Class::set_klass(java_mirror(), NULL);
282 }
283
284 // Need to take this class off the class loader data list.
285 loader_data->remove_class(this);
286
287 // The array_klass for this class is created later, after error handling.
288 // For class redefinition, we keep the original class so this scratch class
289 // doesn't have an array class. Either way, assert that there is nothing
290 // to deallocate.
291 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
292
293 // Release C heap allocated data that this might point to, which includes
294 // reference counting symbol names.
295 release_C_heap_structures();
296
297 deallocate_methods(loader_data, methods());
298 set_methods(NULL);
299
300 if (method_ordering() != NULL &&
301 method_ordering() != Universe::the_empty_int_array() &&
302 !method_ordering()->is_shared()) {
303 MetadataFactory::free_array<int>(loader_data, method_ordering());
304 }
305 set_method_ordering(NULL);
306
307 // default methods can be empty
308 if (default_methods() != NULL &&
309 default_methods() != Universe::the_empty_method_array() &&
310 !default_methods()->is_shared()) {
311 MetadataFactory::free_array<Method*>(loader_data, default_methods());
312 }
313 // Do NOT deallocate the default methods, they are owned by superinterfaces.
314 set_default_methods(NULL);
315
316 // default methods vtable indices can be empty
317 if (default_vtable_indices() != NULL &&
318 !default_vtable_indices()->is_shared()) {
319 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
320 }
321 set_default_vtable_indices(NULL);
322
323
324 // This array is in Klass, but remove it with the InstanceKlass since
325 // this place would be the only caller and it can share memory with transitive
326 // interfaces.
327 if (secondary_supers() != NULL &&
328 secondary_supers() != Universe::the_empty_klass_array() &&
329 secondary_supers() != transitive_interfaces() &&
330 !secondary_supers()->is_shared()) {
331 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
332 }
333 set_secondary_supers(NULL);
334
335 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
336 set_transitive_interfaces(NULL);
337 set_local_interfaces(NULL);
338
339 if (fields() != NULL && !fields()->is_shared()) {
340 MetadataFactory::free_array<jushort>(loader_data, fields());
341 }
342 set_fields(NULL, 0);
343
344 // If a method from a redefined class is using this constant pool, don't
345 // delete it, yet. The new class's previous version will point to this.
346 if (constants() != NULL) {
347 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
348 if (!constants()->is_shared()) {
349 MetadataFactory::free_metadata(loader_data, constants());
350 }
351 // Delete any cached resolution errors for the constant pool
352 SystemDictionary::delete_resolution_error(constants());
353
354 set_constants(NULL);
355 }
356
357 if (inner_classes() != NULL &&
358 inner_classes() != Universe::the_empty_short_array() &&
359 !inner_classes()->is_shared()) {
360 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
361 }
362 set_inner_classes(NULL);
363
364 // We should deallocate the Annotations instance if it's not in shared spaces.
365 if (annotations() != NULL && !annotations()->is_shared()) {
366 MetadataFactory::free_metadata(loader_data, annotations());
367 }
368 set_annotations(NULL);
369 }
370
371 bool InstanceKlass::should_be_initialized() const {
372 return !is_initialized();
373 }
374
375 klassItable* InstanceKlass::itable() const {
376 return new klassItable(instanceKlassHandle(this));
377 }
378
379 void InstanceKlass::eager_initialize(Thread *thread) {
380 if (!EagerInitialization) return;
381
382 if (this->is_not_initialized()) {
383 // abort if the the class has a class initializer
384 if (this->class_initializer() != NULL) return;
385
386 // abort if it is java.lang.Object (initialization is handled in genesis)
387 Klass* super = this->super();
388 if (super == NULL) return;
389
390 // abort if the super class should be initialized
391 if (!InstanceKlass::cast(super)->is_initialized()) return;
392
393 // call body to expose the this pointer
394 instanceKlassHandle this_k(thread, this);
395 eager_initialize_impl(this_k);
396 }
397 }
398
399 // JVMTI spec thinks there are signers and protection domain in the
400 // instanceKlass. These accessors pretend these fields are there.
401 // The hprof specification also thinks these fields are in InstanceKlass.
402 oop InstanceKlass::protection_domain() const {
403 // return the protection_domain from the mirror
404 return java_lang_Class::protection_domain(java_mirror());
405 }
406
407 // To remove these from requires an incompatible change and CCC request.
408 objArrayOop InstanceKlass::signers() const {
409 // return the signers from the mirror
410 return java_lang_Class::signers(java_mirror());
411 }
412
413 oop InstanceKlass::init_lock() const {
414 // return the init lock from the mirror
415 oop lock = java_lang_Class::init_lock(java_mirror());
416 // Prevent reordering with any access of initialization state
417 OrderAccess::loadload();
418 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
419 "only fully initialized state can have a null lock");
420 return lock;
421 }
422
423 // Set the initialization lock to null so the object can be GC'ed. Any racing
424 // threads to get this lock will see a null lock and will not lock.
425 // That's okay because they all check for initialized state after getting
426 // the lock and return.
427 void InstanceKlass::fence_and_clear_init_lock() {
428 // make sure previous stores are all done, notably the init_state.
429 OrderAccess::storestore();
430 java_lang_Class::set_init_lock(java_mirror(), NULL);
431 assert(!is_not_initialized(), "class must be initialized now");
432 }
433
434 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
435 EXCEPTION_MARK;
436 oop init_lock = this_k->init_lock();
437 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
438
439 // abort if someone beat us to the initialization
440 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized()
441
442 ClassState old_state = this_k->init_state();
443 link_class_impl(this_k, true, THREAD);
444 if (HAS_PENDING_EXCEPTION) {
445 CLEAR_PENDING_EXCEPTION;
446 // Abort if linking the class throws an exception.
447
448 // Use a test to avoid redundantly resetting the state if there's
449 // no change. Set_init_state() asserts that state changes make
450 // progress, whereas here we might just be spinning in place.
451 if( old_state != this_k->_init_state )
452 this_k->set_init_state (old_state);
453 } else {
454 // linking successfull, mark class as initialized
455 this_k->set_init_state (fully_initialized);
456 this_k->fence_and_clear_init_lock();
457 // trace
458 if (log_is_enabled(Info, class, init)) {
459 ResourceMark rm(THREAD);
460 log_info(class, init)("[Initialized %s without side effects]", this_k->external_name());
461 }
462 }
463 }
464
465
466 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
467 // process. The step comments refers to the procedure described in that section.
468 // Note: implementation moved to static method to expose the this pointer.
469 void InstanceKlass::initialize(TRAPS) {
470 if (this->should_be_initialized()) {
471 HandleMark hm(THREAD);
472 instanceKlassHandle this_k(THREAD, this);
473 initialize_impl(this_k, CHECK);
474 // Note: at this point the class may be initialized
475 // OR it may be in the state of being initialized
476 // in case of recursive initialization!
477 } else {
478 assert(is_initialized(), "sanity check");
479 }
480 }
481
482
483 bool InstanceKlass::verify_code(
484 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
485 // 1) Verify the bytecodes
486 Verifier::Mode mode =
487 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
488 return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
489 }
490
491
492 // Used exclusively by the shared spaces dump mechanism to prevent
493 // classes mapped into the shared regions in new VMs from appearing linked.
494
495 void InstanceKlass::unlink_class() {
496 assert(is_linked(), "must be linked");
497 _init_state = loaded;
498 }
499
500 void InstanceKlass::link_class(TRAPS) {
501 assert(is_loaded(), "must be loaded");
502 if (!is_linked()) {
503 HandleMark hm(THREAD);
504 instanceKlassHandle this_k(THREAD, this);
505 link_class_impl(this_k, true, CHECK);
506 }
507 }
508
509 // Called to verify that a class can link during initialization, without
510 // throwing a VerifyError.
511 bool InstanceKlass::link_class_or_fail(TRAPS) {
512 assert(is_loaded(), "must be loaded");
513 if (!is_linked()) {
514 HandleMark hm(THREAD);
515 instanceKlassHandle this_k(THREAD, this);
516 link_class_impl(this_k, false, CHECK_false);
517 }
518 return is_linked();
519 }
520
521 bool InstanceKlass::link_class_impl(
522 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
523 if (DumpSharedSpaces && this_k->is_in_error_state()) {
524 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
525 // the class has failed verification. Throwing the NoClassDefFoundError here is just
526 // a convenient way to stop repeat attempts to verify the same (bad) class.
527 //
528 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
529 // if we are executing Java code. This is not a problem for CDS dumping phase since
530 // it doesn't execute any Java code.
531 ResourceMark rm(THREAD);
532 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
533 this_k->external_name(), false);
534 }
535 // return if already verified
536 if (this_k->is_linked()) {
537 return true;
538 }
539
540 // Timing
541 // timer handles recursion
542 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
543 JavaThread* jt = (JavaThread*)THREAD;
544
545 // link super class before linking this class
546 instanceKlassHandle super(THREAD, this_k->super());
547 if (super.not_null()) {
548 if (super->is_interface()) { // check if super class is an interface
549 ResourceMark rm(THREAD);
550 Exceptions::fthrow(
551 THREAD_AND_LOCATION,
552 vmSymbols::java_lang_IncompatibleClassChangeError(),
553 "class %s has interface %s as super class",
554 this_k->external_name(),
555 super->external_name()
556 );
557 return false;
558 }
559
560 link_class_impl(super, throw_verifyerror, CHECK_false);
561 }
562
563 // link all interfaces implemented by this class before linking this class
564 Array<Klass*>* interfaces = this_k->local_interfaces();
565 int num_interfaces = interfaces->length();
566 for (int index = 0; index < num_interfaces; index++) {
567 HandleMark hm(THREAD);
568 instanceKlassHandle ih(THREAD, interfaces->at(index));
569 link_class_impl(ih, throw_verifyerror, CHECK_false);
570 }
571
572 // in case the class is linked in the process of linking its superclasses
573 if (this_k->is_linked()) {
574 return true;
575 }
576
577 // trace only the link time for this klass that includes
578 // the verification time
579 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
580 ClassLoader::perf_class_link_selftime(),
581 ClassLoader::perf_classes_linked(),
582 jt->get_thread_stat()->perf_recursion_counts_addr(),
583 jt->get_thread_stat()->perf_timers_addr(),
584 PerfClassTraceTime::CLASS_LINK);
585
586 // verification & rewriting
587 {
588 oop init_lock = this_k->init_lock();
589 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
590 // rewritten will have been set if loader constraint error found
591 // on an earlier link attempt
592 // don't verify or rewrite if already rewritten
593
594 if (!this_k->is_linked()) {
595 if (!this_k->is_rewritten()) {
596 {
597 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
598 if (!verify_ok) {
599 return false;
600 }
601 }
602
603 // Just in case a side-effect of verify linked this class already
604 // (which can sometimes happen since the verifier loads classes
605 // using custom class loaders, which are free to initialize things)
606 if (this_k->is_linked()) {
607 return true;
608 }
609
610 // also sets rewritten
611 this_k->rewrite_class(CHECK_false);
612 } else if (this_k->is_shared()) {
613 SystemDictionaryShared::check_verification_constraints(this_k, CHECK_false);
614 }
615
616 // relocate jsrs and link methods after they are all rewritten
617 this_k->link_methods(CHECK_false);
618
619 // Initialize the vtable and interface table after
620 // methods have been rewritten since rewrite may
621 // fabricate new Method*s.
622 // also does loader constraint checking
623 //
624 // initialize_vtable and initialize_itable need to be rerun for
625 // a shared class if the class is not loaded by the NULL classloader.
626 ClassLoaderData * loader_data = this_k->class_loader_data();
627 if (!(this_k->is_shared() &&
628 loader_data->is_the_null_class_loader_data())) {
629 ResourceMark rm(THREAD);
630 this_k->vtable()->initialize_vtable(true, CHECK_false);
631 this_k->itable()->initialize_itable(true, CHECK_false);
632 }
633 #ifdef ASSERT
634 else {
635 ResourceMark rm(THREAD);
636 this_k->vtable()->verify(tty, true);
637 // In case itable verification is ever added.
638 // this_k->itable()->verify(tty, true);
639 }
640 #endif
641 this_k->set_init_state(linked);
642 if (JvmtiExport::should_post_class_prepare()) {
643 Thread *thread = THREAD;
644 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
645 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
646 }
647 }
648 }
649 return true;
650 }
651
652
653 // Rewrite the byte codes of all of the methods of a class.
654 // The rewriter must be called exactly once. Rewriting must happen after
655 // verification but before the first method of the class is executed.
656 void InstanceKlass::rewrite_class(TRAPS) {
657 assert(is_loaded(), "must be loaded");
658 instanceKlassHandle this_k(THREAD, this);
659 if (this_k->is_rewritten()) {
660 assert(this_k()->is_shared(), "rewriting an unshared class?");
661 return;
662 }
663 Rewriter::rewrite(this_k, CHECK);
664 this_k->set_rewritten();
665 }
666
667 // Now relocate and link method entry points after class is rewritten.
668 // This is outside is_rewritten flag. In case of an exception, it can be
669 // executed more than once.
670 void InstanceKlass::link_methods(TRAPS) {
671 int len = methods()->length();
672 for (int i = len-1; i >= 0; i--) {
673 methodHandle m(THREAD, methods()->at(i));
674
675 // Set up method entry points for compiler and interpreter .
676 m->link_method(m, CHECK);
677 }
678 }
679
680 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
681 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
682 assert (this_k->has_nonstatic_concrete_methods(), "caller should have checked this");
683 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
684 Klass* iface = this_k->local_interfaces()->at(i);
685 InstanceKlass* ik = InstanceKlass::cast(iface);
686
687 // Initialization is depth first search ie. we start with top of the inheritance tree
688 // has_nonstatic_concrete_methods drives searching superinterfaces since it
689 // means has_nonstatic_concrete_methods in its superinterface hierarchy
690 if (ik->has_nonstatic_concrete_methods()) {
691 ik->initialize_super_interfaces(ik, CHECK);
692 }
693
694 // Only initialize() interfaces that "declare" concrete methods.
695 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
696 ik->initialize(CHECK);
697 }
698 }
699 }
700
701 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
702 // Make sure klass is linked (verified) before initialization
703 // A class could already be verified, since it has been reflected upon.
704 this_k->link_class(CHECK);
705
706 DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
707
708 bool wait = false;
709
710 // refer to the JVM book page 47 for description of steps
711 // Step 1
712 {
713 oop init_lock = this_k->init_lock();
714 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
715
716 Thread *self = THREAD; // it's passed the current thread
717
718 // Step 2
719 // If we were to use wait() instead of waitInterruptibly() then
720 // we might end up throwing IE from link/symbol resolution sites
721 // that aren't expected to throw. This would wreak havoc. See 6320309.
722 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
723 wait = true;
724 ol.waitUninterruptibly(CHECK);
725 }
726
727 // Step 3
728 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
729 DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
730 return;
731 }
732
733 // Step 4
734 if (this_k->is_initialized()) {
735 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
736 return;
737 }
738
739 // Step 5
740 if (this_k->is_in_error_state()) {
741 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
742 ResourceMark rm(THREAD);
743 const char* desc = "Could not initialize class ";
744 const char* className = this_k->external_name();
745 size_t msglen = strlen(desc) + strlen(className) + 1;
746 char* message = NEW_RESOURCE_ARRAY(char, msglen);
747 if (NULL == message) {
748 // Out of memory: can't create detailed error message
749 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
750 } else {
751 jio_snprintf(message, msglen, "%s%s", desc, className);
752 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
753 }
754 }
755
756 // Step 6
757 this_k->set_init_state(being_initialized);
758 this_k->set_init_thread(self);
759 }
760
761 // Step 7
762 // Next, if C is a class rather than an interface, initialize it's super class and super
763 // interfaces.
764 if (!this_k->is_interface()) {
765 Klass* super_klass = this_k->super();
766 if (super_klass != NULL && super_klass->should_be_initialized()) {
767 super_klass->initialize(THREAD);
768 }
769 // If C implements any interface that declares a non-static, concrete method,
770 // the initialization of C triggers initialization of its super interfaces.
771 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
772 // having a superinterface that declares, non-static, concrete methods
773 if (!HAS_PENDING_EXCEPTION && this_k->has_nonstatic_concrete_methods()) {
774 this_k->initialize_super_interfaces(this_k, THREAD);
775 }
776
777 // If any exceptions, complete abruptly, throwing the same exception as above.
778 if (HAS_PENDING_EXCEPTION) {
779 Handle e(THREAD, PENDING_EXCEPTION);
780 CLEAR_PENDING_EXCEPTION;
781 {
782 EXCEPTION_MARK;
783 // Locks object, set state, and notify all waiting threads
784 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
785 CLEAR_PENDING_EXCEPTION;
786 }
787 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
788 THROW_OOP(e());
789 }
790 }
791
792
793 if (UseAOT) {
794 // Look for aot compiled methods for this klass, including class initializer.
795 AOTLoader::load_for_klass(this_k, THREAD);
796 }
797
798 // Step 8
799 {
800 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
801 JavaThread* jt = (JavaThread*)THREAD;
802 DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
803 // Timer includes any side effects of class initialization (resolution,
804 // etc), but not recursive entry into call_class_initializer().
805 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
806 ClassLoader::perf_class_init_selftime(),
807 ClassLoader::perf_classes_inited(),
808 jt->get_thread_stat()->perf_recursion_counts_addr(),
809 jt->get_thread_stat()->perf_timers_addr(),
810 PerfClassTraceTime::CLASS_CLINIT);
811 this_k->call_class_initializer(THREAD);
812 }
813
814 // Step 9
815 if (!HAS_PENDING_EXCEPTION) {
816 this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
817 { ResourceMark rm(THREAD);
818 debug_only(this_k->vtable()->verify(tty, true);)
819 }
820 }
821 else {
822 // Step 10 and 11
823 Handle e(THREAD, PENDING_EXCEPTION);
824 CLEAR_PENDING_EXCEPTION;
825 // JVMTI has already reported the pending exception
826 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
827 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
828 {
829 EXCEPTION_MARK;
830 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
831 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
832 // JVMTI has already reported the pending exception
833 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
834 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
835 }
836 DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
837 if (e->is_a(SystemDictionary::Error_klass())) {
838 THROW_OOP(e());
839 } else {
840 JavaCallArguments args(e);
841 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
842 vmSymbols::throwable_void_signature(),
843 &args);
844 }
845 }
846 DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
847 }
848
849
850 // Note: implementation moved to static method to expose the this pointer.
851 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
852 instanceKlassHandle kh(THREAD, this);
853 set_initialization_state_and_notify_impl(kh, state, CHECK);
854 }
855
856 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
857 oop init_lock = this_k->init_lock();
858 if (init_lock != NULL) {
859 ObjectLocker ol(init_lock, THREAD);
860 this_k->set_init_state(state);
861 this_k->fence_and_clear_init_lock();
862 ol.notify_all(CHECK);
863 } else {
864 assert(init_lock != NULL, "The initialization state should never be set twice");
865 this_k->set_init_state(state);
866 }
867 }
868
869 // The embedded _implementor field can only record one implementor.
870 // When there are more than one implementors, the _implementor field
871 // is set to the interface Klass* itself. Following are the possible
872 // values for the _implementor field:
873 // NULL - no implementor
874 // implementor Klass* - one implementor
875 // self - more than one implementor
876 //
877 // The _implementor field only exists for interfaces.
878 void InstanceKlass::add_implementor(Klass* k) {
879 assert(Compile_lock->owned_by_self(), "");
880 assert(is_interface(), "not interface");
881 // Filter out my subinterfaces.
882 // (Note: Interfaces are never on the subklass list.)
883 if (InstanceKlass::cast(k)->is_interface()) return;
884
885 // Filter out subclasses whose supers already implement me.
886 // (Note: CHA must walk subclasses of direct implementors
887 // in order to locate indirect implementors.)
888 Klass* sk = k->super();
889 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
890 // We only need to check one immediate superclass, since the
891 // implements_interface query looks at transitive_interfaces.
892 // Any supers of the super have the same (or fewer) transitive_interfaces.
893 return;
894
895 Klass* ik = implementor();
896 if (ik == NULL) {
897 set_implementor(k);
898 } else if (ik != this) {
899 // There is already an implementor. Use itself as an indicator of
900 // more than one implementors.
901 set_implementor(this);
902 }
903
904 // The implementor also implements the transitive_interfaces
905 for (int index = 0; index < local_interfaces()->length(); index++) {
906 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
907 }
908 }
909
910 void InstanceKlass::init_implementor() {
911 if (is_interface()) {
912 set_implementor(NULL);
913 }
914 }
915
916
917 void InstanceKlass::process_interfaces(Thread *thread) {
918 // link this class into the implementors list of every interface it implements
919 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
920 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
921 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
922 assert(interf->is_interface(), "expected interface");
923 interf->add_implementor(this);
924 }
925 }
926
927 bool InstanceKlass::can_be_primary_super_slow() const {
928 if (is_interface())
929 return false;
930 else
931 return Klass::can_be_primary_super_slow();
932 }
933
934 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
935 // The secondaries are the implemented interfaces.
936 Array<Klass*>* interfaces = transitive_interfaces();
937 int num_secondaries = num_extra_slots + interfaces->length();
938 if (num_secondaries == 0) {
939 // Must share this for correct bootstrapping!
940 set_secondary_supers(Universe::the_empty_klass_array());
941 return NULL;
942 } else if (num_extra_slots == 0) {
943 // The secondary super list is exactly the same as the transitive interfaces.
944 // Redefine classes has to be careful not to delete this!
945 set_secondary_supers(interfaces);
946 return NULL;
947 } else {
948 // Copy transitive interfaces to a temporary growable array to be constructed
949 // into the secondary super list with extra slots.
950 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
951 for (int i = 0; i < interfaces->length(); i++) {
952 secondaries->push(interfaces->at(i));
953 }
954 return secondaries;
955 }
956 }
957
958 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
959 if (k->is_interface()) {
960 return implements_interface(k);
961 } else {
962 return Klass::compute_is_subtype_of(k);
963 }
964 }
965
966 bool InstanceKlass::implements_interface(Klass* k) const {
967 if (this == k) return true;
968 assert(k->is_interface(), "should be an interface class");
969 for (int i = 0; i < transitive_interfaces()->length(); i++) {
970 if (transitive_interfaces()->at(i) == k) {
971 return true;
972 }
973 }
974 return false;
975 }
976
977 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
978 // Verify direct super interface
979 if (this == k) return true;
980 assert(k->is_interface(), "should be an interface class");
981 for (int i = 0; i < local_interfaces()->length(); i++) {
982 if (local_interfaces()->at(i) == k) {
983 return true;
984 }
985 }
986 return false;
987 }
988
989 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
990 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
991 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
992 report_java_out_of_memory("Requested array size exceeds VM limit");
993 JvmtiExport::post_array_size_exhausted();
994 THROW_OOP_0(Universe::out_of_memory_error_array_size());
995 }
996 int size = objArrayOopDesc::object_size(length);
997 Klass* ak = array_klass(n, CHECK_NULL);
998 KlassHandle h_ak (THREAD, ak);
999 objArrayOop o =
1000 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1001 return o;
1002 }
1003
1004 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1005 if (TraceFinalizerRegistration) {
1006 tty->print("Registered ");
1007 i->print_value_on(tty);
1008 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1009 }
1010 instanceHandle h_i(THREAD, i);
1011 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1012 JavaValue result(T_VOID);
1013 JavaCallArguments args(h_i);
1014 methodHandle mh (THREAD, Universe::finalizer_register_method());
1015 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1016 return h_i();
1017 }
1018
1019 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1020 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1021 int size = size_helper(); // Query before forming handle.
1022
1023 KlassHandle h_k(THREAD, this);
1024
1025 instanceOop i;
1026
1027 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1028 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1029 i = register_finalizer(i, CHECK_NULL);
1030 }
1031 return i;
1032 }
1033
1034 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1035 if (is_interface() || is_abstract()) {
1036 ResourceMark rm(THREAD);
1037 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1038 : vmSymbols::java_lang_InstantiationException(), external_name());
1039 }
1040 if (this == SystemDictionary::Class_klass()) {
1041 ResourceMark rm(THREAD);
1042 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1043 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1044 }
1045 }
1046
1047 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1048 instanceKlassHandle this_k(THREAD, this);
1049 return array_klass_impl(this_k, or_null, n, THREAD);
1050 }
1051
1052 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1053 // Need load-acquire for lock-free read
1054 if (this_k->array_klasses_acquire() == NULL) {
1055 if (or_null) return NULL;
1056
1057 ResourceMark rm;
1058 JavaThread *jt = (JavaThread *)THREAD;
1059 {
1060 // Atomic creation of array_klasses
1061 MutexLocker mc(Compile_lock, THREAD); // for vtables
1062 MutexLocker ma(MultiArray_lock, THREAD);
1063
1064 // Check if update has already taken place
1065 if (this_k->array_klasses() == NULL) {
1066 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1067 // use 'release' to pair with lock-free load
1068 this_k->release_set_array_klasses(k);
1069 }
1070 }
1071 }
1072 // _this will always be set at this point
1073 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1074 if (or_null) {
1075 return oak->array_klass_or_null(n);
1076 }
1077 return oak->array_klass(n, THREAD);
1078 }
1079
1080 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1081 return array_klass_impl(or_null, 1, THREAD);
1082 }
1083
1084 void InstanceKlass::call_class_initializer(TRAPS) {
1085 instanceKlassHandle ik (THREAD, this);
1086 call_class_initializer_impl(ik, THREAD);
1087 }
1088
1089 static int call_class_initializer_impl_counter = 0; // for debugging
1090
1091 Method* InstanceKlass::class_initializer() {
1092 Method* clinit = find_method(
1093 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1094 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1095 return clinit;
1096 }
1097 return NULL;
1098 }
1099
1100 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1101 if (ReplayCompiles &&
1102 (ReplaySuppressInitializers == 1 ||
1103 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1104 // Hide the existence of the initializer for the purpose of replaying the compile
1105 return;
1106 }
1107
1108 methodHandle h_method(THREAD, this_k->class_initializer());
1109 assert(!this_k->is_initialized(), "we cannot initialize twice");
1110 if (log_is_enabled(Info, class, init)) {
1111 ResourceMark rm;
1112 outputStream* log = Log(class, init)::info_stream();
1113 log->print("%d Initializing ", call_class_initializer_impl_counter++);
1114 this_k->name()->print_value_on(log);
1115 log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1116 }
1117 if (h_method() != NULL) {
1118 JavaCallArguments args; // No arguments
1119 JavaValue result(T_VOID);
1120 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1121 }
1122 }
1123
1124
1125 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1126 InterpreterOopMap* entry_for) {
1127 // Lazily create the _oop_map_cache at first request
1128 // Lock-free access requires load_ptr_acquire.
1129 OopMapCache* oop_map_cache =
1130 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache));
1131 if (oop_map_cache == NULL) {
1132 MutexLocker x(OopMapCacheAlloc_lock);
1133 // Check if _oop_map_cache was allocated while we were waiting for this lock
1134 if ((oop_map_cache = _oop_map_cache) == NULL) {
1135 oop_map_cache = new OopMapCache();
1136 // Ensure _oop_map_cache is stable, since it is examined without a lock
1137 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache);
1138 }
1139 }
1140 // _oop_map_cache is constant after init; lookup below does its own locking.
1141 oop_map_cache->lookup(method, bci, entry_for);
1142 }
1143
1144
1145 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1146 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1147 Symbol* f_name = fs.name();
1148 Symbol* f_sig = fs.signature();
1149 if (f_name == name && f_sig == sig) {
1150 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1151 return true;
1152 }
1153 }
1154 return false;
1155 }
1156
1157
1158 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1159 const int n = local_interfaces()->length();
1160 for (int i = 0; i < n; i++) {
1161 Klass* intf1 = local_interfaces()->at(i);
1162 assert(intf1->is_interface(), "just checking type");
1163 // search for field in current interface
1164 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1165 assert(fd->is_static(), "interface field must be static");
1166 return intf1;
1167 }
1168 // search for field in direct superinterfaces
1169 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1170 if (intf2 != NULL) return intf2;
1171 }
1172 // otherwise field lookup fails
1173 return NULL;
1174 }
1175
1176
1177 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1178 // search order according to newest JVM spec (5.4.3.2, p.167).
1179 // 1) search for field in current klass
1180 if (find_local_field(name, sig, fd)) {
1181 return const_cast<InstanceKlass*>(this);
1182 }
1183 // 2) search for field recursively in direct superinterfaces
1184 { Klass* intf = find_interface_field(name, sig, fd);
1185 if (intf != NULL) return intf;
1186 }
1187 // 3) apply field lookup recursively if superclass exists
1188 { Klass* supr = super();
1189 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1190 }
1191 // 4) otherwise field lookup fails
1192 return NULL;
1193 }
1194
1195
1196 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1197 // search order according to newest JVM spec (5.4.3.2, p.167).
1198 // 1) search for field in current klass
1199 if (find_local_field(name, sig, fd)) {
1200 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1201 }
1202 // 2) search for field recursively in direct superinterfaces
1203 if (is_static) {
1204 Klass* intf = find_interface_field(name, sig, fd);
1205 if (intf != NULL) return intf;
1206 }
1207 // 3) apply field lookup recursively if superclass exists
1208 { Klass* supr = super();
1209 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1210 }
1211 // 4) otherwise field lookup fails
1212 return NULL;
1213 }
1214
1215
1216 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1217 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1218 if (fs.offset() == offset) {
1219 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1220 if (fd->is_static() == is_static) return true;
1221 }
1222 }
1223 return false;
1224 }
1225
1226
1227 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1228 Klass* klass = const_cast<InstanceKlass*>(this);
1229 while (klass != NULL) {
1230 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1231 return true;
1232 }
1233 klass = klass->super();
1234 }
1235 return false;
1236 }
1237
1238
1239 void InstanceKlass::methods_do(void f(Method* method)) {
1240 // Methods aren't stable until they are loaded. This can be read outside
1241 // a lock through the ClassLoaderData for profiling
1242 if (!is_loaded()) {
1243 return;
1244 }
1245
1246 int len = methods()->length();
1247 for (int index = 0; index < len; index++) {
1248 Method* m = methods()->at(index);
1249 assert(m->is_method(), "must be method");
1250 f(m);
1251 }
1252 }
1253
1254
1255 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1256 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1257 if (fs.access_flags().is_static()) {
1258 fieldDescriptor& fd = fs.field_descriptor();
1259 cl->do_field(&fd);
1260 }
1261 }
1262 }
1263
1264
1265 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1266 instanceKlassHandle h_this(THREAD, this);
1267 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1268 }
1269
1270
1271 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1272 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1273 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1274 if (fs.access_flags().is_static()) {
1275 fieldDescriptor& fd = fs.field_descriptor();
1276 f(&fd, mirror, CHECK);
1277 }
1278 }
1279 }
1280
1281
1282 static int compare_fields_by_offset(int* a, int* b) {
1283 return a[0] - b[0];
1284 }
1285
1286 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1287 InstanceKlass* super = superklass();
1288 if (super != NULL) {
1289 super->do_nonstatic_fields(cl);
1290 }
1291 fieldDescriptor fd;
1292 int length = java_fields_count();
1293 // In DebugInfo nonstatic fields are sorted by offset.
1294 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1295 int j = 0;
1296 for (int i = 0; i < length; i += 1) {
1297 fd.reinitialize(this, i);
1298 if (!fd.is_static()) {
1299 fields_sorted[j + 0] = fd.offset();
1300 fields_sorted[j + 1] = i;
1301 j += 2;
1302 }
1303 }
1304 if (j > 0) {
1305 length = j;
1306 // _sort_Fn is defined in growableArray.hpp.
1307 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1308 for (int i = 0; i < length; i += 2) {
1309 fd.reinitialize(this, fields_sorted[i + 1]);
1310 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1311 cl->do_field(&fd);
1312 }
1313 }
1314 FREE_C_HEAP_ARRAY(int, fields_sorted);
1315 }
1316
1317
1318 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1319 if (array_klasses() != NULL)
1320 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1321 }
1322
1323 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1324 if (array_klasses() != NULL)
1325 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1326 }
1327
1328 #ifdef ASSERT
1329 static int linear_search(const Array<Method*>* methods,
1330 const Symbol* name,
1331 const Symbol* signature) {
1332 const int len = methods->length();
1333 for (int index = 0; index < len; index++) {
1334 const Method* const m = methods->at(index);
1335 assert(m->is_method(), "must be method");
1336 if (m->signature() == signature && m->name() == name) {
1337 return index;
1338 }
1339 }
1340 return -1;
1341 }
1342 #endif
1343
1344 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1345 int len = methods->length();
1346 // methods are sorted, so do binary search
1347 int l = 0;
1348 int h = len - 1;
1349 while (l <= h) {
1350 int mid = (l + h) >> 1;
1351 Method* m = methods->at(mid);
1352 assert(m->is_method(), "must be method");
1353 int res = m->name()->fast_compare(name);
1354 if (res == 0) {
1355 return mid;
1356 } else if (res < 0) {
1357 l = mid + 1;
1358 } else {
1359 h = mid - 1;
1360 }
1361 }
1362 return -1;
1363 }
1364
1365 // find_method looks up the name/signature in the local methods array
1366 Method* InstanceKlass::find_method(const Symbol* name,
1367 const Symbol* signature) const {
1368 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1369 }
1370
1371 Method* InstanceKlass::find_method_impl(const Symbol* name,
1372 const Symbol* signature,
1373 OverpassLookupMode overpass_mode,
1374 StaticLookupMode static_mode,
1375 PrivateLookupMode private_mode) const {
1376 return InstanceKlass::find_method_impl(methods(),
1377 name,
1378 signature,
1379 overpass_mode,
1380 static_mode,
1381 private_mode);
1382 }
1383
1384 // find_instance_method looks up the name/signature in the local methods array
1385 // and skips over static methods
1386 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1387 const Symbol* name,
1388 const Symbol* signature) {
1389 Method* const meth = InstanceKlass::find_method_impl(methods,
1390 name,
1391 signature,
1392 find_overpass,
1393 skip_static,
1394 find_private);
1395 assert(((meth == NULL) || !meth->is_static()),
1396 "find_instance_method should have skipped statics");
1397 return meth;
1398 }
1399
1400 // find_instance_method looks up the name/signature in the local methods array
1401 // and skips over static methods
1402 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1403 return InstanceKlass::find_instance_method(methods(), name, signature);
1404 }
1405
1406 // Find looks up the name/signature in the local methods array
1407 // and filters on the overpass, static and private flags
1408 // This returns the first one found
1409 // note that the local methods array can have up to one overpass, one static
1410 // and one instance (private or not) with the same name/signature
1411 Method* InstanceKlass::find_local_method(const Symbol* name,
1412 const Symbol* signature,
1413 OverpassLookupMode overpass_mode,
1414 StaticLookupMode static_mode,
1415 PrivateLookupMode private_mode) const {
1416 return InstanceKlass::find_method_impl(methods(),
1417 name,
1418 signature,
1419 overpass_mode,
1420 static_mode,
1421 private_mode);
1422 }
1423
1424 // Find looks up the name/signature in the local methods array
1425 // and filters on the overpass, static and private flags
1426 // This returns the first one found
1427 // note that the local methods array can have up to one overpass, one static
1428 // and one instance (private or not) with the same name/signature
1429 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1430 const Symbol* name,
1431 const Symbol* signature,
1432 OverpassLookupMode overpass_mode,
1433 StaticLookupMode static_mode,
1434 PrivateLookupMode private_mode) {
1435 return InstanceKlass::find_method_impl(methods,
1436 name,
1437 signature,
1438 overpass_mode,
1439 static_mode,
1440 private_mode);
1441 }
1442
1443 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1444 const Symbol* name,
1445 const Symbol* signature) {
1446 return InstanceKlass::find_method_impl(methods,
1447 name,
1448 signature,
1449 find_overpass,
1450 find_static,
1451 find_private);
1452 }
1453
1454 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1455 const Symbol* name,
1456 const Symbol* signature,
1457 OverpassLookupMode overpass_mode,
1458 StaticLookupMode static_mode,
1459 PrivateLookupMode private_mode) {
1460 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1461 return hit >= 0 ? methods->at(hit): NULL;
1462 }
1463
1464 // true if method matches signature and conforms to skipping_X conditions.
1465 static bool method_matches(const Method* m,
1466 const Symbol* signature,
1467 bool skipping_overpass,
1468 bool skipping_static,
1469 bool skipping_private) {
1470 return ((m->signature() == signature) &&
1471 (!skipping_overpass || !m->is_overpass()) &&
1472 (!skipping_static || !m->is_static()) &&
1473 (!skipping_private || !m->is_private()));
1474 }
1475
1476 // Used directly for default_methods to find the index into the
1477 // default_vtable_indices, and indirectly by find_method
1478 // find_method_index looks in the local methods array to return the index
1479 // of the matching name/signature. If, overpass methods are being ignored,
1480 // the search continues to find a potential non-overpass match. This capability
1481 // is important during method resolution to prefer a static method, for example,
1482 // over an overpass method.
1483 // There is the possibility in any _method's array to have the same name/signature
1484 // for a static method, an overpass method and a local instance method
1485 // To correctly catch a given method, the search criteria may need
1486 // to explicitly skip the other two. For local instance methods, it
1487 // is often necessary to skip private methods
1488 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1489 const Symbol* name,
1490 const Symbol* signature,
1491 OverpassLookupMode overpass_mode,
1492 StaticLookupMode static_mode,
1493 PrivateLookupMode private_mode) {
1494 const bool skipping_overpass = (overpass_mode == skip_overpass);
1495 const bool skipping_static = (static_mode == skip_static);
1496 const bool skipping_private = (private_mode == skip_private);
1497 const int hit = binary_search(methods, name);
1498 if (hit != -1) {
1499 const Method* const m = methods->at(hit);
1500
1501 // Do linear search to find matching signature. First, quick check
1502 // for common case, ignoring overpasses if requested.
1503 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1504 return hit;
1505 }
1506
1507 // search downwards through overloaded methods
1508 int i;
1509 for (i = hit - 1; i >= 0; --i) {
1510 const Method* const m = methods->at(i);
1511 assert(m->is_method(), "must be method");
1512 if (m->name() != name) {
1513 break;
1514 }
1515 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1516 return i;
1517 }
1518 }
1519 // search upwards
1520 for (i = hit + 1; i < methods->length(); ++i) {
1521 const Method* const m = methods->at(i);
1522 assert(m->is_method(), "must be method");
1523 if (m->name() != name) {
1524 break;
1525 }
1526 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1527 return i;
1528 }
1529 }
1530 // not found
1531 #ifdef ASSERT
1532 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1533 linear_search(methods, name, signature);
1534 assert(-1 == index, "binary search should have found entry %d", index);
1535 #endif
1536 }
1537 return -1;
1538 }
1539
1540 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1541 return find_method_by_name(methods(), name, end);
1542 }
1543
1544 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1545 const Symbol* name,
1546 int* end_ptr) {
1547 assert(end_ptr != NULL, "just checking");
1548 int start = binary_search(methods, name);
1549 int end = start + 1;
1550 if (start != -1) {
1551 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1552 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1553 *end_ptr = end;
1554 return start;
1555 }
1556 return -1;
1557 }
1558
1559 // uncached_lookup_method searches both the local class methods array and all
1560 // superclasses methods arrays, skipping any overpass methods in superclasses.
1561 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1562 const Symbol* signature,
1563 OverpassLookupMode overpass_mode) const {
1564 OverpassLookupMode overpass_local_mode = overpass_mode;
1565 const Klass* klass = this;
1566 while (klass != NULL) {
1567 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1568 signature,
1569 overpass_local_mode,
1570 find_static,
1571 find_private);
1572 if (method != NULL) {
1573 return method;
1574 }
1575 klass = klass->super();
1576 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1577 }
1578 return NULL;
1579 }
1580
1581 #ifdef ASSERT
1582 // search through class hierarchy and return true if this class or
1583 // one of the superclasses was redefined
1584 bool InstanceKlass::has_redefined_this_or_super() const {
1585 const Klass* klass = this;
1586 while (klass != NULL) {
1587 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1588 return true;
1589 }
1590 klass = klass->super();
1591 }
1592 return false;
1593 }
1594 #endif
1595
1596 // lookup a method in the default methods list then in all transitive interfaces
1597 // Do NOT return private or static methods
1598 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1599 Symbol* signature) const {
1600 Method* m = NULL;
1601 if (default_methods() != NULL) {
1602 m = find_method(default_methods(), name, signature);
1603 }
1604 // Look up interfaces
1605 if (m == NULL) {
1606 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1607 }
1608 return m;
1609 }
1610
1611 // lookup a method in all the interfaces that this class implements
1612 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1613 // They should only be found in the initial InterfaceMethodRef
1614 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1615 Symbol* signature,
1616 DefaultsLookupMode defaults_mode) const {
1617 Array<Klass*>* all_ifs = transitive_interfaces();
1618 int num_ifs = all_ifs->length();
1619 InstanceKlass *ik = NULL;
1620 for (int i = 0; i < num_ifs; i++) {
1621 ik = InstanceKlass::cast(all_ifs->at(i));
1622 Method* m = ik->lookup_method(name, signature);
1623 if (m != NULL && m->is_public() && !m->is_static() &&
1624 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1625 return m;
1626 }
1627 }
1628 return NULL;
1629 }
1630
1631 /* jni_id_for_impl for jfieldIds only */
1632 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1633 MutexLocker ml(JfieldIdCreation_lock);
1634 // Retry lookup after we got the lock
1635 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1636 if (probe == NULL) {
1637 // Slow case, allocate new static field identifier
1638 probe = new JNIid(this_k(), offset, this_k->jni_ids());
1639 this_k->set_jni_ids(probe);
1640 }
1641 return probe;
1642 }
1643
1644
1645 /* jni_id_for for jfieldIds only */
1646 JNIid* InstanceKlass::jni_id_for(int offset) {
1647 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1648 if (probe == NULL) {
1649 probe = jni_id_for_impl(this, offset);
1650 }
1651 return probe;
1652 }
1653
1654 u2 InstanceKlass::enclosing_method_data(int offset) const {
1655 const Array<jushort>* const inner_class_list = inner_classes();
1656 if (inner_class_list == NULL) {
1657 return 0;
1658 }
1659 const int length = inner_class_list->length();
1660 if (length % inner_class_next_offset == 0) {
1661 return 0;
1662 }
1663 const int index = length - enclosing_method_attribute_size;
1664 assert(offset < enclosing_method_attribute_size, "invalid offset");
1665 return inner_class_list->at(index + offset);
1666 }
1667
1668 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1669 u2 method_index) {
1670 Array<jushort>* inner_class_list = inner_classes();
1671 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1672 int length = inner_class_list->length();
1673 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1674 int index = length - enclosing_method_attribute_size;
1675 inner_class_list->at_put(
1676 index + enclosing_method_class_index_offset, class_index);
1677 inner_class_list->at_put(
1678 index + enclosing_method_method_index_offset, method_index);
1679 }
1680 }
1681
1682 // Lookup or create a jmethodID.
1683 // This code is called by the VMThread and JavaThreads so the
1684 // locking has to be done very carefully to avoid deadlocks
1685 // and/or other cache consistency problems.
1686 //
1687 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1688 size_t idnum = (size_t)method_h->method_idnum();
1689 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1690 size_t length = 0;
1691 jmethodID id = NULL;
1692
1693 // We use a double-check locking idiom here because this cache is
1694 // performance sensitive. In the normal system, this cache only
1695 // transitions from NULL to non-NULL which is safe because we use
1696 // release_set_methods_jmethod_ids() to advertise the new cache.
1697 // A partially constructed cache should never be seen by a racing
1698 // thread. We also use release_store_ptr() to save a new jmethodID
1699 // in the cache so a partially constructed jmethodID should never be
1700 // seen either. Cache reads of existing jmethodIDs proceed without a
1701 // lock, but cache writes of a new jmethodID requires uniqueness and
1702 // creation of the cache itself requires no leaks so a lock is
1703 // generally acquired in those two cases.
1704 //
1705 // If the RedefineClasses() API has been used, then this cache can
1706 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1707 // Cache creation requires no leaks and we require safety between all
1708 // cache accesses and freeing of the old cache so a lock is generally
1709 // acquired when the RedefineClasses() API has been used.
1710
1711 if (jmeths != NULL) {
1712 // the cache already exists
1713 if (!ik_h->idnum_can_increment()) {
1714 // the cache can't grow so we can just get the current values
1715 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1716 } else {
1717 // cache can grow so we have to be more careful
1718 if (Threads::number_of_threads() == 0 ||
1719 SafepointSynchronize::is_at_safepoint()) {
1720 // we're single threaded or at a safepoint - no locking needed
1721 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1722 } else {
1723 MutexLocker ml(JmethodIdCreation_lock);
1724 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1725 }
1726 }
1727 }
1728 // implied else:
1729 // we need to allocate a cache so default length and id values are good
1730
1731 if (jmeths == NULL || // no cache yet
1732 length <= idnum || // cache is too short
1733 id == NULL) { // cache doesn't contain entry
1734
1735 // This function can be called by the VMThread so we have to do all
1736 // things that might block on a safepoint before grabbing the lock.
1737 // Otherwise, we can deadlock with the VMThread or have a cache
1738 // consistency issue. These vars keep track of what we might have
1739 // to free after the lock is dropped.
1740 jmethodID to_dealloc_id = NULL;
1741 jmethodID* to_dealloc_jmeths = NULL;
1742
1743 // may not allocate new_jmeths or use it if we allocate it
1744 jmethodID* new_jmeths = NULL;
1745 if (length <= idnum) {
1746 // allocate a new cache that might be used
1747 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1748 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1749 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1750 // cache size is stored in element[0], other elements offset by one
1751 new_jmeths[0] = (jmethodID)size;
1752 }
1753
1754 // allocate a new jmethodID that might be used
1755 jmethodID new_id = NULL;
1756 if (method_h->is_old() && !method_h->is_obsolete()) {
1757 // The method passed in is old (but not obsolete), we need to use the current version
1758 Method* current_method = ik_h->method_with_idnum((int)idnum);
1759 assert(current_method != NULL, "old and but not obsolete, so should exist");
1760 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1761 } else {
1762 // It is the current version of the method or an obsolete method,
1763 // use the version passed in
1764 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1765 }
1766
1767 if (Threads::number_of_threads() == 0 ||
1768 SafepointSynchronize::is_at_safepoint()) {
1769 // we're single threaded or at a safepoint - no locking needed
1770 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1771 &to_dealloc_id, &to_dealloc_jmeths);
1772 } else {
1773 MutexLocker ml(JmethodIdCreation_lock);
1774 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1775 &to_dealloc_id, &to_dealloc_jmeths);
1776 }
1777
1778 // The lock has been dropped so we can free resources.
1779 // Free up either the old cache or the new cache if we allocated one.
1780 if (to_dealloc_jmeths != NULL) {
1781 FreeHeap(to_dealloc_jmeths);
1782 }
1783 // free up the new ID since it wasn't needed
1784 if (to_dealloc_id != NULL) {
1785 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1786 }
1787 }
1788 return id;
1789 }
1790
1791 // Figure out how many jmethodIDs haven't been allocated, and make
1792 // sure space for them is pre-allocated. This makes getting all
1793 // method ids much, much faster with classes with more than 8
1794 // methods, and has a *substantial* effect on performance with jvmti
1795 // code that loads all jmethodIDs for all classes.
1796 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1797 int new_jmeths = 0;
1798 int length = methods()->length();
1799 for (int index = start_offset; index < length; index++) {
1800 Method* m = methods()->at(index);
1801 jmethodID id = m->find_jmethod_id_or_null();
1802 if (id == NULL) {
1803 new_jmeths++;
1804 }
1805 }
1806 if (new_jmeths != 0) {
1807 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1808 }
1809 }
1810
1811 // Common code to fetch the jmethodID from the cache or update the
1812 // cache with the new jmethodID. This function should never do anything
1813 // that causes the caller to go to a safepoint or we can deadlock with
1814 // the VMThread or have cache consistency issues.
1815 //
1816 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1817 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1818 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1819 jmethodID** to_dealloc_jmeths_p) {
1820 assert(new_id != NULL, "sanity check");
1821 assert(to_dealloc_id_p != NULL, "sanity check");
1822 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1823 assert(Threads::number_of_threads() == 0 ||
1824 SafepointSynchronize::is_at_safepoint() ||
1825 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1826
1827 // reacquire the cache - we are locked, single threaded or at a safepoint
1828 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1829 jmethodID id = NULL;
1830 size_t length = 0;
1831
1832 if (jmeths == NULL || // no cache yet
1833 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1834 if (jmeths != NULL) {
1835 // copy any existing entries from the old cache
1836 for (size_t index = 0; index < length; index++) {
1837 new_jmeths[index+1] = jmeths[index+1];
1838 }
1839 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1840 }
1841 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1842 } else {
1843 // fetch jmethodID (if any) from the existing cache
1844 id = jmeths[idnum+1];
1845 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1846 }
1847 if (id == NULL) {
1848 // No matching jmethodID in the existing cache or we have a new
1849 // cache or we just grew the cache. This cache write is done here
1850 // by the first thread to win the foot race because a jmethodID
1851 // needs to be unique once it is generally available.
1852 id = new_id;
1853
1854 // The jmethodID cache can be read while unlocked so we have to
1855 // make sure the new jmethodID is complete before installing it
1856 // in the cache.
1857 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1858 } else {
1859 *to_dealloc_id_p = new_id; // save new id for later delete
1860 }
1861 return id;
1862 }
1863
1864
1865 // Common code to get the jmethodID cache length and the jmethodID
1866 // value at index idnum if there is one.
1867 //
1868 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1869 size_t idnum, size_t *length_p, jmethodID* id_p) {
1870 assert(cache != NULL, "sanity check");
1871 assert(length_p != NULL, "sanity check");
1872 assert(id_p != NULL, "sanity check");
1873
1874 // cache size is stored in element[0], other elements offset by one
1875 *length_p = (size_t)cache[0];
1876 if (*length_p <= idnum) { // cache is too short
1877 *id_p = NULL;
1878 } else {
1879 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1880 }
1881 }
1882
1883
1884 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1885 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1886 size_t idnum = (size_t)method->method_idnum();
1887 jmethodID* jmeths = methods_jmethod_ids_acquire();
1888 size_t length; // length assigned as debugging crumb
1889 jmethodID id = NULL;
1890 if (jmeths != NULL && // If there is a cache
1891 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1892 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1893 }
1894 return id;
1895 }
1896
1897 inline DependencyContext InstanceKlass::dependencies() {
1898 DependencyContext dep_context(&_dep_context);
1899 return dep_context;
1900 }
1901
1902 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1903 return dependencies().mark_dependent_nmethods(changes);
1904 }
1905
1906 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1907 dependencies().add_dependent_nmethod(nm);
1908 }
1909
1910 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1911 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1912 }
1913
1914 #ifndef PRODUCT
1915 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1916 dependencies().print_dependent_nmethods(verbose);
1917 }
1918
1919 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1920 return dependencies().is_dependent_nmethod(nm);
1921 }
1922 #endif //PRODUCT
1923
1924 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1925 clean_implementors_list(is_alive);
1926 clean_method_data(is_alive);
1927
1928 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1929 DependencyContext dep_context(&_dep_context);
1930 dep_context.expunge_stale_entries();
1931 }
1932
1933 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1934 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1935 if (is_interface()) {
1936 if (ClassUnloading) {
1937 Klass* impl = implementor();
1938 if (impl != NULL) {
1939 if (!impl->is_loader_alive(is_alive)) {
1940 // remove this guy
1941 Klass** klass = adr_implementor();
1942 assert(klass != NULL, "null klass");
1943 if (klass != NULL) {
1944 *klass = NULL;
1945 }
1946 }
1947 }
1948 }
1949 }
1950 }
1951
1952 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1953 for (int m = 0; m < methods()->length(); m++) {
1954 MethodData* mdo = methods()->at(m)->method_data();
1955 if (mdo != NULL) {
1956 mdo->clean_method_data(is_alive);
1957 }
1958 }
1959 }
1960
1961 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
1962 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
1963 ResourceMark rm;
1964 log_trace(classfingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
1965 return false;
1966 }
1967
1968 Array<Klass*>* local_interfaces = this->local_interfaces();
1969 if (local_interfaces != NULL) {
1970 int length = local_interfaces->length();
1971 for (int i = 0; i < length; i++) {
1972 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
1973 if (!intf->has_passed_fingerprint_check()) {
1974 ResourceMark rm;
1975 log_trace(classfingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
1976 return false;
1977 }
1978 }
1979 }
1980
1981 return true;
1982 }
1983
1984 bool InstanceKlass::should_store_fingerprint() {
1985 #if INCLUDE_AOT
1986 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
1987 if (EnableJVMCI && !UseJVMCICompiler) {
1988 // (1) We are running AOT to generate a shared library.
1989 return true;
1990 }
1991 if (DumpSharedSpaces) {
1992 // (2) We are running -Xshare:dump to create a shared archive
1993 return true;
1994 }
1995 #endif
1996
1997 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
1998 // but do not store the 64-bit fingerprint to save space.
1999 return false;
2000 }
2001
2002 bool InstanceKlass::has_stored_fingerprint() const {
2003 #if INCLUDE_AOT
2004 return should_store_fingerprint() || is_shared();
2005 #else
2006 return false;
2007 #endif
2008 }
2009
2010 uint64_t InstanceKlass::get_stored_fingerprint() const {
2011 if (has_stored_fingerprint()) {
2012 address adr = adr_fingerprint();
2013 assert(adr != NULL, "sanity");
2014 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2015 }
2016 return 0;
2017 }
2018
2019 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2020 assert(should_store_fingerprint(), "must be");
2021 address adr = adr_fingerprint();
2022 assert(adr != NULL, "sanity");
2023 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2024
2025 ResourceMark rm;
2026 log_trace(classfingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2027 }
2028
2029 static void remove_unshareable_in_class(Klass* k) {
2030 // remove klass's unshareable info
2031 k->remove_unshareable_info();
2032 }
2033
2034 void InstanceKlass::remove_unshareable_info() {
2035 Klass::remove_unshareable_info();
2036 // Unlink the class
2037 if (is_linked()) {
2038 unlink_class();
2039 }
2040 init_implementor();
2041
2042 constants()->remove_unshareable_info();
2043
2044 assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
2045
2046 for (int i = 0; i < methods()->length(); i++) {
2047 Method* m = methods()->at(i);
2048 m->remove_unshareable_info();
2049 }
2050
2051 // do array classes also.
2052 array_klasses_do(remove_unshareable_in_class);
2053 }
2054
2055 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2056 // Array classes have null protection domain.
2057 // --> see ArrayKlass::complete_create_array_klass()
2058 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2059 }
2060
2061 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2062 instanceKlassHandle ik(THREAD, this);
2063 ik->set_package(loader_data, CHECK);
2064 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2065
2066 Array<Method*>* methods = ik->methods();
2067 int num_methods = methods->length();
2068 for (int index2 = 0; index2 < num_methods; ++index2) {
2069 methodHandle m(THREAD, methods->at(index2));
2070 m->restore_unshareable_info(CHECK);
2071 }
2072 if (JvmtiExport::has_redefined_a_class()) {
2073 // Reinitialize vtable because RedefineClasses may have changed some
2074 // entries in this vtable for super classes so the CDS vtable might
2075 // point to old or obsolete entries. RedefineClasses doesn't fix up
2076 // vtables in the shared system dictionary, only the main one.
2077 // It also redefines the itable too so fix that too.
2078 ResourceMark rm(THREAD);
2079 ik->vtable()->initialize_vtable(false, CHECK);
2080 ik->itable()->initialize_itable(false, CHECK);
2081 }
2082
2083 // restore constant pool resolved references
2084 ik->constants()->restore_unshareable_info(CHECK);
2085
2086 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2087 }
2088
2089 // returns true IFF is_in_error_state() has been changed as a result of this call.
2090 bool InstanceKlass::check_sharing_error_state() {
2091 assert(DumpSharedSpaces, "should only be called during dumping");
2092 bool old_state = is_in_error_state();
2093
2094 if (!is_in_error_state()) {
2095 bool bad = false;
2096 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2097 if (sup->is_in_error_state()) {
2098 bad = true;
2099 break;
2100 }
2101 }
2102 if (!bad) {
2103 Array<Klass*>* interfaces = transitive_interfaces();
2104 for (int i = 0; i < interfaces->length(); i++) {
2105 Klass* iface = interfaces->at(i);
2106 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2107 bad = true;
2108 break;
2109 }
2110 }
2111 }
2112
2113 if (bad) {
2114 set_in_error_state();
2115 }
2116 }
2117
2118 return (old_state != is_in_error_state());
2119 }
2120
2121 #if INCLUDE_JVMTI
2122 static void clear_all_breakpoints(Method* m) {
2123 m->clear_all_breakpoints();
2124 }
2125 #endif
2126
2127 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2128 // notify the debugger
2129 if (JvmtiExport::should_post_class_unload()) {
2130 JvmtiExport::post_class_unload(ik);
2131 }
2132
2133 // notify ClassLoadingService of class unload
2134 ClassLoadingService::notify_class_unloaded(ik);
2135 }
2136
2137 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2138 // Clean up C heap
2139 ik->release_C_heap_structures();
2140 ik->constants()->release_C_heap_structures();
2141 }
2142
2143 void InstanceKlass::release_C_heap_structures() {
2144 assert(!this->is_shared(), "should not be called for a shared class");
2145
2146 // Can't release the constant pool here because the constant pool can be
2147 // deallocated separately from the InstanceKlass for default methods and
2148 // redefine classes.
2149
2150 // Deallocate oop map cache
2151 if (_oop_map_cache != NULL) {
2152 delete _oop_map_cache;
2153 _oop_map_cache = NULL;
2154 }
2155
2156 // Deallocate JNI identifiers for jfieldIDs
2157 JNIid::deallocate(jni_ids());
2158 set_jni_ids(NULL);
2159
2160 jmethodID* jmeths = methods_jmethod_ids_acquire();
2161 if (jmeths != (jmethodID*)NULL) {
2162 release_set_methods_jmethod_ids(NULL);
2163 FreeHeap(jmeths);
2164 }
2165
2166 // Deallocate MemberNameTable
2167 {
2168 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2169 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2170 MemberNameTable* mnt = member_names();
2171 if (mnt != NULL) {
2172 delete mnt;
2173 set_member_names(NULL);
2174 }
2175 }
2176
2177 // Release dependencies.
2178 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2179 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2180 // context can contain live dependencies, since there's a race between nmethod &
2181 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2182 // dependencies aren't removed from the context associated with the class (see
2183 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2184 // live dependencies pointing to unloaded nmethods and causes a crash in
2185 // DC::remove_all_dependents() when it touches unloaded nmethod.
2186 dependencies().wipe();
2187
2188 #if INCLUDE_JVMTI
2189 // Deallocate breakpoint records
2190 if (breakpoints() != 0x0) {
2191 methods_do(clear_all_breakpoints);
2192 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2193 }
2194
2195 // deallocate the cached class file
2196 if (_cached_class_file != NULL) {
2197 os::free(_cached_class_file);
2198 _cached_class_file = NULL;
2199 }
2200 #endif
2201
2202 // Decrement symbol reference counts associated with the unloaded class.
2203 if (_name != NULL) _name->decrement_refcount();
2204 // unreference array name derived from this class name (arrays of an unloaded
2205 // class can't be referenced anymore).
2206 if (_array_name != NULL) _array_name->decrement_refcount();
2207 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2208
2209 assert(_total_instanceKlass_count >= 1, "Sanity check");
2210 Atomic::dec(&_total_instanceKlass_count);
2211 }
2212
2213 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2214 if (array == NULL) {
2215 _source_debug_extension = NULL;
2216 } else {
2217 // Adding one to the attribute length in order to store a null terminator
2218 // character could cause an overflow because the attribute length is
2219 // already coded with an u4 in the classfile, but in practice, it's
2220 // unlikely to happen.
2221 assert((length+1) > length, "Overflow checking");
2222 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2223 for (int i = 0; i < length; i++) {
2224 sde[i] = array[i];
2225 }
2226 sde[length] = '\0';
2227 _source_debug_extension = sde;
2228 }
2229 }
2230
2231 address InstanceKlass::static_field_addr(int offset) {
2232 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2233 }
2234
2235
2236 const char* InstanceKlass::signature_name() const {
2237 int hash_len = 0;
2238 char hash_buf[40];
2239
2240 // If this is an anonymous class, append a hash to make the name unique
2241 if (is_anonymous()) {
2242 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2243 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2244 hash_len = (int)strlen(hash_buf);
2245 }
2246
2247 // Get the internal name as a c string
2248 const char* src = (const char*) (name()->as_C_string());
2249 const int src_length = (int)strlen(src);
2250
2251 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2252
2253 // Add L as type indicator
2254 int dest_index = 0;
2255 dest[dest_index++] = 'L';
2256
2257 // Add the actual class name
2258 for (int src_index = 0; src_index < src_length; ) {
2259 dest[dest_index++] = src[src_index++];
2260 }
2261
2262 // If we have a hash, append it
2263 for (int hash_index = 0; hash_index < hash_len; ) {
2264 dest[dest_index++] = hash_buf[hash_index++];
2265 }
2266
2267 // Add the semicolon and the NULL
2268 dest[dest_index++] = ';';
2269 dest[dest_index] = '\0';
2270 return dest;
2271 }
2272
2273 // Used to obtain the package name from a fully qualified class name.
2274 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2275 if (name == NULL) {
2276 return NULL;
2277 } else {
2278 if (name->utf8_length() <= 0) {
2279 return NULL;
2280 }
2281 ResourceMark rm;
2282 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2283 if (package_name == NULL) {
2284 return NULL;
2285 }
2286 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2287 return pkg_name;
2288 }
2289 }
2290
2291 ModuleEntry* InstanceKlass::module() const {
2292 if (!in_unnamed_package()) {
2293 return _package_entry->module();
2294 }
2295 const Klass* host = host_klass();
2296 if (host == NULL) {
2297 return class_loader_data()->modules()->unnamed_module();
2298 }
2299 return host->class_loader_data()->modules()->unnamed_module();
2300 }
2301
2302 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2303
2304 // ensure java/ packages only loaded by boot or platform builtin loaders
2305 check_prohibited_package(name(), loader_data->class_loader(), CHECK);
2306
2307 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2308
2309 if (pkg_name != NULL && loader_data != NULL) {
2310
2311 // Find in class loader's package entry table.
2312 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2313
2314 // If the package name is not found in the loader's package
2315 // entry table, it is an indication that the package has not
2316 // been defined. Consider it defined within the unnamed module.
2317 if (_package_entry == NULL) {
2318 ResourceMark rm;
2319
2320 if (!ModuleEntryTable::javabase_defined()) {
2321 // Before java.base is defined during bootstrapping, define all packages in
2322 // the java.base module. If a non-java.base package is erroneously placed
2323 // in the java.base module it will be caught later when java.base
2324 // is defined by ModuleEntryTable::verify_javabase_packages check.
2325 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, "java.base module is NULL");
2326 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2327 } else {
2328 assert(loader_data->modules()->unnamed_module() != NULL, "unnamed module is NULL");
2329 _package_entry = loader_data->packages()->lookup(pkg_name,
2330 loader_data->modules()->unnamed_module());
2331 }
2332
2333 // A package should have been successfully created
2334 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2335 name()->as_C_string(), loader_data->loader_name());
2336 }
2337
2338 if (log_is_enabled(Debug, modules)) {
2339 ResourceMark rm;
2340 ModuleEntry* m = _package_entry->module();
2341 log_trace(modules)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2342 external_name(),
2343 pkg_name->as_C_string(),
2344 loader_data->loader_name(),
2345 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2346 }
2347 } else {
2348 ResourceMark rm;
2349 log_trace(modules)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2350 external_name(),
2351 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2352 UNNAMED_MODULE);
2353 }
2354 }
2355
2356
2357 // different versions of is_same_class_package
2358
2359 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2360 oop classloader1 = this->class_loader();
2361 PackageEntry* classpkg1 = this->package();
2362 if (class2->is_objArray_klass()) {
2363 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2364 }
2365
2366 oop classloader2;
2367 PackageEntry* classpkg2;
2368 if (class2->is_instance_klass()) {
2369 classloader2 = class2->class_loader();
2370 classpkg2 = class2->package();
2371 } else {
2372 assert(class2->is_typeArray_klass(), "should be type array");
2373 classloader2 = NULL;
2374 classpkg2 = NULL;
2375 }
2376
2377 // Same package is determined by comparing class loader
2378 // and package entries. Both must be the same. This rule
2379 // applies even to classes that are defined in the unnamed
2380 // package, they still must have the same class loader.
2381 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2382 return true;
2383 }
2384
2385 return false;
2386 }
2387
2388 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2389 const Symbol* other_class_name) const {
2390 oop this_class_loader = class_loader();
2391 const Symbol* const this_class_name = name();
2392
2393 return InstanceKlass::is_same_class_package(this_class_loader,
2394 this_class_name,
2395 other_class_loader,
2396 other_class_name);
2397 }
2398
2399 // return true if two classes are in the same package, classloader
2400 // and classname information is enough to determine a class's package
2401 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1,
2402 oop class_loader2, const Symbol* class_name2) {
2403 if (class_loader1 != class_loader2) {
2404 return false;
2405 } else if (class_name1 == class_name2) {
2406 return true;
2407 } else {
2408 ResourceMark rm;
2409
2410 bool bad_class_name = false;
2411 const char* name1 = ClassLoader::package_from_name((const char*) class_name1->as_C_string(), &bad_class_name);
2412 if (bad_class_name) {
2413 return false;
2414 }
2415
2416 const char* name2 = ClassLoader::package_from_name((const char*) class_name2->as_C_string(), &bad_class_name);
2417 if (bad_class_name) {
2418 return false;
2419 }
2420
2421 if ((name1 == NULL) || (name2 == NULL)) {
2422 // One of the two doesn't have a package. Only return true
2423 // if the other one also doesn't have a package.
2424 return name1 == name2;
2425 }
2426
2427 // Check that package is identical
2428 return (strcmp(name1, name2) == 0);
2429 }
2430 }
2431
2432 // Returns true iff super_method can be overridden by a method in targetclassname
2433 // See JLS 3rd edition 8.4.6.1
2434 // Assumes name-signature match
2435 // "this" is InstanceKlass of super_method which must exist
2436 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2437 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2438 // Private methods can not be overridden
2439 if (super_method->is_private()) {
2440 return false;
2441 }
2442 // If super method is accessible, then override
2443 if ((super_method->is_protected()) ||
2444 (super_method->is_public())) {
2445 return true;
2446 }
2447 // Package-private methods are not inherited outside of package
2448 assert(super_method->is_package_private(), "must be package private");
2449 return(is_same_class_package(targetclassloader(), targetclassname));
2450 }
2451
2452 /* defined for now in jvm.cpp, for historical reasons *--
2453 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2454 Symbol*& simple_name_result, TRAPS) {
2455 ...
2456 }
2457 */
2458
2459 // Only boot and platform class loaders can define classes in "java/" packages.
2460 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2461 Handle class_loader,
2462 TRAPS) {
2463 const char* javapkg = "java/";
2464 ResourceMark rm(THREAD);
2465 if (!class_loader.is_null() &&
2466 !SystemDictionary::is_platform_class_loader(class_loader) &&
2467 class_name != NULL &&
2468 strncmp(class_name->as_C_string(), javapkg, strlen(javapkg)) == 0) {
2469 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2470 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2471 char* name = pkg_name->as_C_string();
2472 const char* class_loader_name = InstanceKlass::cast(class_loader()->klass())->name()->as_C_string();
2473 StringUtils::replace_no_expand(name, "/", ".");
2474 const char* msg_text1 = "Class loader (instance of): ";
2475 const char* msg_text2 = " tried to load prohibited package name: ";
2476 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2477 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2478 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2479 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2480 }
2481 return;
2482 }
2483
2484 // tell if two classes have the same enclosing class (at package level)
2485 bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1,
2486 const Klass* class2,
2487 TRAPS) {
2488 if (class2 == class1) return true;
2489 if (!class2->is_instance_klass()) return false;
2490
2491 // must be in same package before we try anything else
2492 if (!class1->is_same_class_package(class2))
2493 return false;
2494
2495 // As long as there is an outer1.getEnclosingClass,
2496 // shift the search outward.
2497 const InstanceKlass* outer1 = class1;
2498 for (;;) {
2499 // As we walk along, look for equalities between outer1 and class2.
2500 // Eventually, the walks will terminate as outer1 stops
2501 // at the top-level class around the original class.
2502 bool ignore_inner_is_member;
2503 const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2504 CHECK_false);
2505 if (next == NULL) break;
2506 if (next == class2) return true;
2507 outer1 = InstanceKlass::cast(next);
2508 }
2509
2510 // Now do the same for class2.
2511 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2512 for (;;) {
2513 bool ignore_inner_is_member;
2514 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2515 CHECK_false);
2516 if (next == NULL) break;
2517 // Might as well check the new outer against all available values.
2518 if (next == class1) return true;
2519 if (next == outer1) return true;
2520 outer2 = InstanceKlass::cast(next);
2521 }
2522
2523 // If by this point we have not found an equality between the
2524 // two classes, we know they are in separate package members.
2525 return false;
2526 }
2527
2528 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) {
2529 constantPoolHandle i_cp(THREAD, k->constants());
2530 for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2531 int ioff = iter.inner_class_info_index();
2532 if (ioff != 0) {
2533 // Check to see if the name matches the class we're looking for
2534 // before attempting to find the class.
2535 if (i_cp->klass_name_at_matches(k, ioff)) {
2536 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2537 if (k() == inner_klass) {
2538 *ooff = iter.outer_class_info_index();
2539 *noff = iter.inner_name_index();
2540 return true;
2541 }
2542 }
2543 }
2544 }
2545 return false;
2546 }
2547
2548 InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k,
2549 bool* inner_is_member,
2550 TRAPS) {
2551 InstanceKlass* outer_klass = NULL;
2552 *inner_is_member = false;
2553 int ooff = 0, noff = 0;
2554 if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2555 constantPoolHandle i_cp(THREAD, k->constants());
2556 if (ooff != 0) {
2557 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2558 outer_klass = InstanceKlass::cast(ok);
2559 *inner_is_member = true;
2560 }
2561 if (NULL == outer_klass) {
2562 // It may be anonymous; try for that.
2563 int encl_method_class_idx = k->enclosing_method_class_index();
2564 if (encl_method_class_idx != 0) {
2565 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2566 outer_klass = InstanceKlass::cast(ok);
2567 *inner_is_member = false;
2568 }
2569 }
2570 }
2571
2572 // If no inner class attribute found for this class.
2573 if (NULL == outer_klass) return NULL;
2574
2575 // Throws an exception if outer klass has not declared k as an inner klass
2576 // We need evidence that each klass knows about the other, or else
2577 // the system could allow a spoof of an inner class to gain access rights.
2578 Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2579 return outer_klass;
2580 }
2581
2582 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2583 jint access = access_flags().as_int();
2584
2585 // But check if it happens to be member class.
2586 instanceKlassHandle ik(THREAD, this);
2587 InnerClassesIterator iter(ik);
2588 for (; !iter.done(); iter.next()) {
2589 int ioff = iter.inner_class_info_index();
2590 // Inner class attribute can be zero, skip it.
2591 // Strange but true: JVM spec. allows null inner class refs.
2592 if (ioff == 0) continue;
2593
2594 // only look at classes that are already loaded
2595 // since we are looking for the flags for our self.
2596 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2597 if ((ik->name() == inner_name)) {
2598 // This is really a member class.
2599 access = iter.inner_access_flags();
2600 break;
2601 }
2602 }
2603 // Remember to strip ACC_SUPER bit
2604 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2605 }
2606
2607 jint InstanceKlass::jvmti_class_status() const {
2608 jint result = 0;
2609
2610 if (is_linked()) {
2611 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2612 }
2613
2614 if (is_initialized()) {
2615 assert(is_linked(), "Class status is not consistent");
2616 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2617 }
2618 if (is_in_error_state()) {
2619 result |= JVMTI_CLASS_STATUS_ERROR;
2620 }
2621 return result;
2622 }
2623
2624 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2625 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2626 int method_table_offset_in_words = ioe->offset()/wordSize;
2627 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2628 / itableOffsetEntry::size();
2629
2630 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2631 // If the interface isn't implemented by the receiver class,
2632 // the VM should throw IncompatibleClassChangeError.
2633 if (cnt >= nof_interfaces) {
2634 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2635 }
2636
2637 Klass* ik = ioe->interface_klass();
2638 if (ik == holder) break;
2639 }
2640
2641 itableMethodEntry* ime = ioe->first_method_entry(this);
2642 Method* m = ime[index].method();
2643 if (m == NULL) {
2644 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2645 }
2646 return m;
2647 }
2648
2649
2650 #if INCLUDE_JVMTI
2651 // update default_methods for redefineclasses for methods that are
2652 // not yet in the vtable due to concurrent subclass define and superinterface
2653 // redefinition
2654 // Note: those in the vtable, should have been updated via adjust_method_entries
2655 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2656 // search the default_methods for uses of either obsolete or EMCP methods
2657 if (default_methods() != NULL) {
2658 for (int index = 0; index < default_methods()->length(); index ++) {
2659 Method* old_method = default_methods()->at(index);
2660 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2661 continue; // skip uninteresting entries
2662 }
2663 assert(!old_method->is_deleted(), "default methods may not be deleted");
2664
2665 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2666
2667 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2668 assert(old_method != new_method, "sanity check");
2669
2670 default_methods()->at_put(index, new_method);
2671 if (log_is_enabled(Info, redefine, class, update)) {
2672 ResourceMark rm;
2673 if (!(*trace_name_printed)) {
2674 log_info(redefine, class, update)
2675 ("adjust: klassname=%s default methods from name=%s",
2676 external_name(), old_method->method_holder()->external_name());
2677 *trace_name_printed = true;
2678 }
2679 log_debug(redefine, class, update, vtables)
2680 ("default method update: %s(%s) ",
2681 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2682 }
2683 }
2684 }
2685 }
2686 #endif // INCLUDE_JVMTI
2687
2688 // On-stack replacement stuff
2689 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2690 // only one compilation can be active
2691 {
2692 // This is a short non-blocking critical region, so the no safepoint check is ok.
2693 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2694 assert(n->is_osr_method(), "wrong kind of nmethod");
2695 n->set_osr_link(osr_nmethods_head());
2696 set_osr_nmethods_head(n);
2697 // Raise the highest osr level if necessary
2698 if (TieredCompilation) {
2699 Method* m = n->method();
2700 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2701 }
2702 }
2703
2704 // Get rid of the osr methods for the same bci that have lower levels.
2705 if (TieredCompilation) {
2706 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2707 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2708 if (inv != NULL && inv->is_in_use()) {
2709 inv->make_not_entrant();
2710 }
2711 }
2712 }
2713 }
2714
2715 // Remove osr nmethod from the list. Return true if found and removed.
2716 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2717 // This is a short non-blocking critical region, so the no safepoint check is ok.
2718 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2719 assert(n->is_osr_method(), "wrong kind of nmethod");
2720 nmethod* last = NULL;
2721 nmethod* cur = osr_nmethods_head();
2722 int max_level = CompLevel_none; // Find the max comp level excluding n
2723 Method* m = n->method();
2724 // Search for match
2725 bool found = false;
2726 while(cur != NULL && cur != n) {
2727 if (TieredCompilation && m == cur->method()) {
2728 // Find max level before n
2729 max_level = MAX2(max_level, cur->comp_level());
2730 }
2731 last = cur;
2732 cur = cur->osr_link();
2733 }
2734 nmethod* next = NULL;
2735 if (cur == n) {
2736 found = true;
2737 next = cur->osr_link();
2738 if (last == NULL) {
2739 // Remove first element
2740 set_osr_nmethods_head(next);
2741 } else {
2742 last->set_osr_link(next);
2743 }
2744 }
2745 n->set_osr_link(NULL);
2746 if (TieredCompilation) {
2747 cur = next;
2748 while (cur != NULL) {
2749 // Find max level after n
2750 if (m == cur->method()) {
2751 max_level = MAX2(max_level, cur->comp_level());
2752 }
2753 cur = cur->osr_link();
2754 }
2755 m->set_highest_osr_comp_level(max_level);
2756 }
2757 return found;
2758 }
2759
2760 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2761 // This is a short non-blocking critical region, so the no safepoint check is ok.
2762 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2763 nmethod* osr = osr_nmethods_head();
2764 int found = 0;
2765 while (osr != NULL) {
2766 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2767 if (osr->method() == m) {
2768 osr->mark_for_deoptimization();
2769 found++;
2770 }
2771 osr = osr->osr_link();
2772 }
2773 return found;
2774 }
2775
2776 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2777 // This is a short non-blocking critical region, so the no safepoint check is ok.
2778 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2779 nmethod* osr = osr_nmethods_head();
2780 nmethod* best = NULL;
2781 while (osr != NULL) {
2782 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2783 // There can be a time when a c1 osr method exists but we are waiting
2784 // for a c2 version. When c2 completes its osr nmethod we will trash
2785 // the c1 version and only be able to find the c2 version. However
2786 // while we overflow in the c1 code at back branches we don't want to
2787 // try and switch to the same code as we are already running
2788
2789 if (osr->method() == m &&
2790 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2791 if (match_level) {
2792 if (osr->comp_level() == comp_level) {
2793 // Found a match - return it.
2794 return osr;
2795 }
2796 } else {
2797 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2798 if (osr->comp_level() == CompLevel_highest_tier) {
2799 // Found the best possible - return it.
2800 return osr;
2801 }
2802 best = osr;
2803 }
2804 }
2805 }
2806 osr = osr->osr_link();
2807 }
2808 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2809 return best;
2810 }
2811 return NULL;
2812 }
2813
2814 bool InstanceKlass::add_member_name(Handle mem_name) {
2815 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2816 MutexLocker ml(MemberNameTable_lock);
2817 DEBUG_ONLY(NoSafepointVerifier nsv);
2818
2819 // Check if method has been redefined while taking out MemberNameTable_lock, if so
2820 // return false. We cannot cache obsolete methods. They will crash when the function
2821 // is called!
2822 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2823 if (method->is_obsolete()) {
2824 return false;
2825 } else if (method->is_old()) {
2826 // Replace method with redefined version
2827 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2828 }
2829
2830 if (_member_names == NULL) {
2831 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2832 }
2833 _member_names->add_member_name(mem_name_wref);
2834 return true;
2835 }
2836
2837 // -----------------------------------------------------------------------------------------------------
2838 // Printing
2839
2840 #ifndef PRODUCT
2841
2842 #define BULLET " - "
2843
2844 static const char* state_names[] = {
2845 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2846 };
2847
2848 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2849 for (int i = 0; i < len; i++) {
2850 intptr_t e = start[i];
2851 st->print("%d : " INTPTR_FORMAT, i, e);
2852 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2853 st->print(" ");
2854 ((Metadata*)e)->print_value_on(st);
2855 }
2856 st->cr();
2857 }
2858 }
2859
2860 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2861 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
2862 }
2863
2864 void InstanceKlass::print_on(outputStream* st) const {
2865 assert(is_klass(), "must be klass");
2866 Klass::print_on(st);
2867
2868 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2869 st->print(BULLET"klass size: %d", size()); st->cr();
2870 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2871 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2872 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2873 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2874 st->print(BULLET"sub: ");
2875 Klass* sub = subklass();
2876 int n;
2877 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2878 if (n < MaxSubklassPrintSize) {
2879 sub->print_value_on(st);
2880 st->print(" ");
2881 }
2882 }
2883 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2884 st->cr();
2885
2886 if (is_interface()) {
2887 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2888 if (nof_implementors() == 1) {
2889 st->print_cr(BULLET"implementor: ");
2890 st->print(" ");
2891 implementor()->print_value_on(st);
2892 st->cr();
2893 }
2894 }
2895
2896 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2897 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2898 if (Verbose || WizardMode) {
2899 Array<Method*>* method_array = methods();
2900 for (int i = 0; i < method_array->length(); i++) {
2901 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2902 }
2903 }
2904 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2905 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2906 if (Verbose && default_methods() != NULL) {
2907 Array<Method*>* method_array = default_methods();
2908 for (int i = 0; i < method_array->length(); i++) {
2909 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2910 }
2911 }
2912 if (default_vtable_indices() != NULL) {
2913 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2914 }
2915 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2916 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2917 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2918 if (class_loader_data() != NULL) {
2919 st->print(BULLET"class loader data: ");
2920 class_loader_data()->print_value_on(st);
2921 st->cr();
2922 }
2923 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2924 if (source_file_name() != NULL) {
2925 st->print(BULLET"source file: ");
2926 source_file_name()->print_value_on(st);
2927 st->cr();
2928 }
2929 if (source_debug_extension() != NULL) {
2930 st->print(BULLET"source debug extension: ");
2931 st->print("%s", source_debug_extension());
2932 st->cr();
2933 }
2934 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2935 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2936 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2937 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2938 {
2939 bool have_pv = false;
2940 // previous versions are linked together through the InstanceKlass
2941 for (InstanceKlass* pv_node = previous_versions();
2942 pv_node != NULL;
2943 pv_node = pv_node->previous_versions()) {
2944 if (!have_pv)
2945 st->print(BULLET"previous version: ");
2946 have_pv = true;
2947 pv_node->constants()->print_value_on(st);
2948 }
2949 if (have_pv) st->cr();
2950 }
2951
2952 if (generic_signature() != NULL) {
2953 st->print(BULLET"generic signature: ");
2954 generic_signature()->print_value_on(st);
2955 st->cr();
2956 }
2957 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2958 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2959 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2960 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2961 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2962 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2963 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2964 FieldPrinter print_static_field(st);
2965 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2966 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2967 FieldPrinter print_nonstatic_field(st);
2968 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2969 ik->do_nonstatic_fields(&print_nonstatic_field);
2970
2971 st->print(BULLET"non-static oop maps: ");
2972 OopMapBlock* map = start_of_nonstatic_oop_maps();
2973 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2974 while (map < end_map) {
2975 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2976 map++;
2977 }
2978 st->cr();
2979 }
2980
2981 #endif //PRODUCT
2982
2983 void InstanceKlass::print_value_on(outputStream* st) const {
2984 assert(is_klass(), "must be klass");
2985 if (Verbose || WizardMode) access_flags().print_on(st);
2986 name()->print_value_on(st);
2987 }
2988
2989 #ifndef PRODUCT
2990
2991 void FieldPrinter::do_field(fieldDescriptor* fd) {
2992 _st->print(BULLET);
2993 if (_obj == NULL) {
2994 fd->print_on(_st);
2995 _st->cr();
2996 } else {
2997 fd->print_on_for(_st, _obj);
2998 _st->cr();
2999 }
3000 }
3001
3002
3003 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3004 Klass::oop_print_on(obj, st);
3005
3006 if (this == SystemDictionary::String_klass()) {
3007 typeArrayOop value = java_lang_String::value(obj);
3008 juint length = java_lang_String::length(obj);
3009 if (value != NULL &&
3010 value->is_typeArray() &&
3011 length <= (juint) value->length()) {
3012 st->print(BULLET"string: ");
3013 java_lang_String::print(obj, st);
3014 st->cr();
3015 if (!WizardMode) return; // that is enough
3016 }
3017 }
3018
3019 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3020 FieldPrinter print_field(st, obj);
3021 do_nonstatic_fields(&print_field);
3022
3023 if (this == SystemDictionary::Class_klass()) {
3024 st->print(BULLET"signature: ");
3025 java_lang_Class::print_signature(obj, st);
3026 st->cr();
3027 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3028 st->print(BULLET"fake entry for mirror: ");
3029 mirrored_klass->print_value_on_maybe_null(st);
3030 st->cr();
3031 Klass* array_klass = java_lang_Class::array_klass(obj);
3032 st->print(BULLET"fake entry for array: ");
3033 array_klass->print_value_on_maybe_null(st);
3034 st->cr();
3035 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3036 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3037 Klass* real_klass = java_lang_Class::as_Klass(obj);
3038 if (real_klass != NULL && real_klass->is_instance_klass()) {
3039 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3040 }
3041 } else if (this == SystemDictionary::MethodType_klass()) {
3042 st->print(BULLET"signature: ");
3043 java_lang_invoke_MethodType::print_signature(obj, st);
3044 st->cr();
3045 }
3046 }
3047
3048 #endif //PRODUCT
3049
3050 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3051 st->print("a ");
3052 name()->print_value_on(st);
3053 obj->print_address_on(st);
3054 if (this == SystemDictionary::String_klass()
3055 && java_lang_String::value(obj) != NULL) {
3056 ResourceMark rm;
3057 int len = java_lang_String::length(obj);
3058 int plen = (len < 24 ? len : 12);
3059 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3060 st->print(" = \"%s\"", str);
3061 if (len > plen)
3062 st->print("...[%d]", len);
3063 } else if (this == SystemDictionary::Class_klass()) {
3064 Klass* k = java_lang_Class::as_Klass(obj);
3065 st->print(" = ");
3066 if (k != NULL) {
3067 k->print_value_on(st);
3068 } else {
3069 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3070 st->print("%s", tname ? tname : "type?");
3071 }
3072 } else if (this == SystemDictionary::MethodType_klass()) {
3073 st->print(" = ");
3074 java_lang_invoke_MethodType::print_signature(obj, st);
3075 } else if (java_lang_boxing_object::is_instance(obj)) {
3076 st->print(" = ");
3077 java_lang_boxing_object::print(obj, st);
3078 } else if (this == SystemDictionary::LambdaForm_klass()) {
3079 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3080 if (vmentry != NULL) {
3081 st->print(" => ");
3082 vmentry->print_value_on(st);
3083 }
3084 } else if (this == SystemDictionary::MemberName_klass()) {
3085 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3086 if (vmtarget != NULL) {
3087 st->print(" = ");
3088 vmtarget->print_value_on(st);
3089 } else {
3090 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3091 st->print(".");
3092 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3093 }
3094 }
3095 }
3096
3097 const char* InstanceKlass::internal_name() const {
3098 return external_name();
3099 }
3100
3101 void InstanceKlass::print_loading_log(LogLevel::type type,
3102 ClassLoaderData* loader_data,
3103 const char* module_name,
3104 const ClassFileStream* cfs) const {
3105 ResourceMark rm;
3106 outputStream* log;
3107
3108 assert(type == LogLevel::Info || type == LogLevel::Debug, "sanity");
3109
3110 if (type == LogLevel::Info) {
3111 log = Log(class, load)::info_stream();
3112 } else {
3113 assert(type == LogLevel::Debug,
3114 "print_loading_log supports only Debug and Info levels");
3115 log = Log(class, load)::debug_stream();
3116 }
3117
3118 // Name and class hierarchy info
3119 log->print("%s", external_name());
3120
3121 // Source
3122 if (cfs != NULL) {
3123 if (cfs->source() != NULL) {
3124 if (module_name != NULL) {
3125 if (ClassLoader::is_jrt(cfs->source())) {
3126 log->print(" source: jrt:/%s", module_name);
3127 } else {
3128 log->print(" source: %s", cfs->source());
3129 }
3130 } else {
3131 log->print(" source: %s", cfs->source());
3132 }
3133 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3134 Thread* THREAD = Thread::current();
3135 Klass* caller =
3136 THREAD->is_Java_thread()
3137 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3138 : NULL;
3139 // caller can be NULL, for example, during a JVMTI VM_Init hook
3140 if (caller != NULL) {
3141 log->print(" source: instance of %s", caller->external_name());
3142 } else {
3143 // source is unknown
3144 }
3145 } else {
3146 Handle class_loader(loader_data->class_loader());
3147 log->print(" source: %s", class_loader->klass()->external_name());
3148 }
3149 } else {
3150 log->print(" source: shared objects file");
3151 }
3152
3153 if (type == LogLevel::Debug) {
3154 // Class hierarchy info
3155 log->print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3156 p2i(this), p2i(superklass()));
3157
3158 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3159 log->print(" interfaces:");
3160 int length = local_interfaces()->length();
3161 for (int i = 0; i < length; i++) {
3162 log->print(" " INTPTR_FORMAT,
3163 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3164 }
3165 }
3166
3167 // Class loader
3168 log->print(" loader: [");
3169 loader_data->print_value_on(log);
3170 log->print("]");
3171
3172 // Classfile checksum
3173 if (cfs) {
3174 log->print(" bytes: %d checksum: %08x",
3175 cfs->length(),
3176 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3177 cfs->length()));
3178 }
3179 }
3180 log->cr();
3181 }
3182
3183 #if INCLUDE_SERVICES
3184 // Size Statistics
3185 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3186 Klass::collect_statistics(sz);
3187
3188 sz->_inst_size = wordSize * size_helper();
3189 sz->_vtab_bytes = wordSize * vtable_length();
3190 sz->_itab_bytes = wordSize * itable_length();
3191 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3192
3193 int n = 0;
3194 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3195 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3196 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3197 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3198 n += (sz->_fields_bytes = sz->count_array(fields()));
3199 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3200 sz->_ro_bytes += n;
3201
3202 const ConstantPool* cp = constants();
3203 if (cp) {
3204 cp->collect_statistics(sz);
3205 }
3206
3207 const Annotations* anno = annotations();
3208 if (anno) {
3209 anno->collect_statistics(sz);
3210 }
3211
3212 const Array<Method*>* methods_array = methods();
3213 if (methods()) {
3214 for (int i = 0; i < methods_array->length(); i++) {
3215 Method* method = methods_array->at(i);
3216 if (method) {
3217 sz->_method_count ++;
3218 method->collect_statistics(sz);
3219 }
3220 }
3221 }
3222 }
3223 #endif // INCLUDE_SERVICES
3224
3225 // Verification
3226
3227 class VerifyFieldClosure: public OopClosure {
3228 protected:
3229 template <class T> void do_oop_work(T* p) {
3230 oop obj = oopDesc::load_decode_heap_oop(p);
3231 if (!obj->is_oop_or_null()) {
3232 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3233 Universe::print_on(tty);
3234 guarantee(false, "boom");
3235 }
3236 }
3237 public:
3238 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3239 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3240 };
3241
3242 void InstanceKlass::verify_on(outputStream* st) {
3243 #ifndef PRODUCT
3244 // Avoid redundant verifies, this really should be in product.
3245 if (_verify_count == Universe::verify_count()) return;
3246 _verify_count = Universe::verify_count();
3247 #endif
3248
3249 // Verify Klass
3250 Klass::verify_on(st);
3251
3252 // Verify that klass is present in ClassLoaderData
3253 guarantee(class_loader_data()->contains_klass(this),
3254 "this class isn't found in class loader data");
3255
3256 // Verify vtables
3257 if (is_linked()) {
3258 ResourceMark rm;
3259 // $$$ This used to be done only for m/s collections. Doing it
3260 // always seemed a valid generalization. (DLD -- 6/00)
3261 vtable()->verify(st);
3262 }
3263
3264 // Verify first subklass
3265 if (subklass() != NULL) {
3266 guarantee(subklass()->is_klass(), "should be klass");
3267 }
3268
3269 // Verify siblings
3270 Klass* super = this->super();
3271 Klass* sib = next_sibling();
3272 if (sib != NULL) {
3273 if (sib == this) {
3274 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3275 }
3276
3277 guarantee(sib->is_klass(), "should be klass");
3278 guarantee(sib->super() == super, "siblings should have same superklass");
3279 }
3280
3281 // Verify implementor fields
3282 Klass* im = implementor();
3283 if (im != NULL) {
3284 guarantee(is_interface(), "only interfaces should have implementor set");
3285 guarantee(im->is_klass(), "should be klass");
3286 guarantee(!im->is_interface() || im == this,
3287 "implementors cannot be interfaces");
3288 }
3289
3290 // Verify local interfaces
3291 if (local_interfaces()) {
3292 Array<Klass*>* local_interfaces = this->local_interfaces();
3293 for (int j = 0; j < local_interfaces->length(); j++) {
3294 Klass* e = local_interfaces->at(j);
3295 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3296 }
3297 }
3298
3299 // Verify transitive interfaces
3300 if (transitive_interfaces() != NULL) {
3301 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3302 for (int j = 0; j < transitive_interfaces->length(); j++) {
3303 Klass* e = transitive_interfaces->at(j);
3304 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3305 }
3306 }
3307
3308 // Verify methods
3309 if (methods() != NULL) {
3310 Array<Method*>* methods = this->methods();
3311 for (int j = 0; j < methods->length(); j++) {
3312 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3313 }
3314 for (int j = 0; j < methods->length() - 1; j++) {
3315 Method* m1 = methods->at(j);
3316 Method* m2 = methods->at(j + 1);
3317 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3318 }
3319 }
3320
3321 // Verify method ordering
3322 if (method_ordering() != NULL) {
3323 Array<int>* method_ordering = this->method_ordering();
3324 int length = method_ordering->length();
3325 if (JvmtiExport::can_maintain_original_method_order() ||
3326 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3327 guarantee(length == methods()->length(), "invalid method ordering length");
3328 jlong sum = 0;
3329 for (int j = 0; j < length; j++) {
3330 int original_index = method_ordering->at(j);
3331 guarantee(original_index >= 0, "invalid method ordering index");
3332 guarantee(original_index < length, "invalid method ordering index");
3333 sum += original_index;
3334 }
3335 // Verify sum of indices 0,1,...,length-1
3336 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3337 } else {
3338 guarantee(length == 0, "invalid method ordering length");
3339 }
3340 }
3341
3342 // Verify default methods
3343 if (default_methods() != NULL) {
3344 Array<Method*>* methods = this->default_methods();
3345 for (int j = 0; j < methods->length(); j++) {
3346 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3347 }
3348 for (int j = 0; j < methods->length() - 1; j++) {
3349 Method* m1 = methods->at(j);
3350 Method* m2 = methods->at(j + 1);
3351 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3352 }
3353 }
3354
3355 // Verify JNI static field identifiers
3356 if (jni_ids() != NULL) {
3357 jni_ids()->verify(this);
3358 }
3359
3360 // Verify other fields
3361 if (array_klasses() != NULL) {
3362 guarantee(array_klasses()->is_klass(), "should be klass");
3363 }
3364 if (constants() != NULL) {
3365 guarantee(constants()->is_constantPool(), "should be constant pool");
3366 }
3367 const Klass* host = host_klass();
3368 if (host != NULL) {
3369 guarantee(host->is_klass(), "should be klass");
3370 }
3371 }
3372
3373 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3374 Klass::oop_verify_on(obj, st);
3375 VerifyFieldClosure blk;
3376 obj->oop_iterate_no_header(&blk);
3377 }
3378
3379
3380 // JNIid class for jfieldIDs only
3381 // Note to reviewers:
3382 // These JNI functions are just moved over to column 1 and not changed
3383 // in the compressed oops workspace.
3384 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3385 _holder = holder;
3386 _offset = offset;
3387 _next = next;
3388 debug_only(_is_static_field_id = false;)
3389 }
3390
3391
3392 JNIid* JNIid::find(int offset) {
3393 JNIid* current = this;
3394 while (current != NULL) {
3395 if (current->offset() == offset) return current;
3396 current = current->next();
3397 }
3398 return NULL;
3399 }
3400
3401 void JNIid::deallocate(JNIid* current) {
3402 while (current != NULL) {
3403 JNIid* next = current->next();
3404 delete current;
3405 current = next;
3406 }
3407 }
3408
3409
3410 void JNIid::verify(Klass* holder) {
3411 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3412 int end_field_offset;
3413 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3414
3415 JNIid* current = this;
3416 while (current != NULL) {
3417 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3418 #ifdef ASSERT
3419 int o = current->offset();
3420 if (current->is_static_field_id()) {
3421 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3422 }
3423 #endif
3424 current = current->next();
3425 }
3426 }
3427
3428
3429 #ifdef ASSERT
3430 void InstanceKlass::set_init_state(ClassState state) {
3431 bool good_state = is_shared() ? (_init_state <= state)
3432 : (_init_state < state);
3433 assert(good_state || state == allocated, "illegal state transition");
3434 _init_state = (u1)state;
3435 }
3436 #endif
3437
3438 #if INCLUDE_JVMTI
3439
3440 // RedefineClasses() support for previous versions
3441
3442 // Globally, there is at least one previous version of a class to walk
3443 // during class unloading, which is saved because old methods in the class
3444 // are still running. Otherwise the previous version list is cleaned up.
3445 bool InstanceKlass::_has_previous_versions = false;
3446
3447 // Returns true if there are previous versions of a class for class
3448 // unloading only. Also resets the flag to false. purge_previous_version
3449 // will set the flag to true if there are any left, i.e., if there's any
3450 // work to do for next time. This is to avoid the expensive code cache
3451 // walk in CLDG::do_unloading().
3452 bool InstanceKlass::has_previous_versions_and_reset() {
3453 bool ret = _has_previous_versions;
3454 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3455 ret ? "true" : "false");
3456 _has_previous_versions = false;
3457 return ret;
3458 }
3459
3460 // Purge previous versions before adding new previous versions of the class and
3461 // during class unloading.
3462 void InstanceKlass::purge_previous_version_list() {
3463 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3464 assert(has_been_redefined(), "Should only be called for main class");
3465
3466 // Quick exit.
3467 if (previous_versions() == NULL) {
3468 return;
3469 }
3470
3471 // This klass has previous versions so see what we can cleanup
3472 // while it is safe to do so.
3473
3474 int deleted_count = 0; // leave debugging breadcrumbs
3475 int live_count = 0;
3476 ClassLoaderData* loader_data = class_loader_data();
3477 assert(loader_data != NULL, "should never be null");
3478
3479 ResourceMark rm;
3480 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3481
3482 // previous versions are linked together through the InstanceKlass
3483 InstanceKlass* pv_node = previous_versions();
3484 InstanceKlass* last = this;
3485 int version = 0;
3486
3487 // check the previous versions list
3488 for (; pv_node != NULL; ) {
3489
3490 ConstantPool* pvcp = pv_node->constants();
3491 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3492
3493 if (!pvcp->on_stack()) {
3494 // If the constant pool isn't on stack, none of the methods
3495 // are executing. Unlink this previous_version.
3496 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3497 // so will be deallocated during the next phase of class unloading.
3498 log_trace(redefine, class, iklass, purge)
3499 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3500 // For debugging purposes.
3501 pv_node->set_is_scratch_class();
3502 // Unlink from previous version list.
3503 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3504 InstanceKlass* next = pv_node->previous_versions();
3505 pv_node->link_previous_versions(NULL); // point next to NULL
3506 last->link_previous_versions(next);
3507 // Add to the deallocate list after unlinking
3508 loader_data->add_to_deallocate_list(pv_node);
3509 pv_node = next;
3510 deleted_count++;
3511 version++;
3512 continue;
3513 } else {
3514 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3515 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3516 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3517 live_count++;
3518 // found a previous version for next time we do class unloading
3519 _has_previous_versions = true;
3520 }
3521
3522 // At least one method is live in this previous version.
3523 // Reset dead EMCP methods not to get breakpoints.
3524 // All methods are deallocated when all of the methods for this class are no
3525 // longer running.
3526 Array<Method*>* method_refs = pv_node->methods();
3527 if (method_refs != NULL) {
3528 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3529 for (int j = 0; j < method_refs->length(); j++) {
3530 Method* method = method_refs->at(j);
3531
3532 if (!method->on_stack()) {
3533 // no breakpoints for non-running methods
3534 if (method->is_running_emcp()) {
3535 method->set_running_emcp(false);
3536 }
3537 } else {
3538 assert (method->is_obsolete() || method->is_running_emcp(),
3539 "emcp method cannot run after emcp bit is cleared");
3540 log_trace(redefine, class, iklass, purge)
3541 ("purge: %s(%s): prev method @%d in version @%d is alive",
3542 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3543 }
3544 }
3545 }
3546 // next previous version
3547 last = pv_node;
3548 pv_node = pv_node->previous_versions();
3549 version++;
3550 }
3551 log_trace(redefine, class, iklass, purge)
3552 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3553 }
3554
3555 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3556 int emcp_method_count) {
3557 int obsolete_method_count = old_methods->length() - emcp_method_count;
3558
3559 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3560 _previous_versions != NULL) {
3561 // We have a mix of obsolete and EMCP methods so we have to
3562 // clear out any matching EMCP method entries the hard way.
3563 int local_count = 0;
3564 for (int i = 0; i < old_methods->length(); i++) {
3565 Method* old_method = old_methods->at(i);
3566 if (old_method->is_obsolete()) {
3567 // only obsolete methods are interesting
3568 Symbol* m_name = old_method->name();
3569 Symbol* m_signature = old_method->signature();
3570
3571 // previous versions are linked together through the InstanceKlass
3572 int j = 0;
3573 for (InstanceKlass* prev_version = _previous_versions;
3574 prev_version != NULL;
3575 prev_version = prev_version->previous_versions(), j++) {
3576
3577 Array<Method*>* method_refs = prev_version->methods();
3578 for (int k = 0; k < method_refs->length(); k++) {
3579 Method* method = method_refs->at(k);
3580
3581 if (!method->is_obsolete() &&
3582 method->name() == m_name &&
3583 method->signature() == m_signature) {
3584 // The current RedefineClasses() call has made all EMCP
3585 // versions of this method obsolete so mark it as obsolete
3586 log_trace(redefine, class, iklass, add)
3587 ("%s(%s): flush obsolete method @%d in version @%d",
3588 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3589
3590 method->set_is_obsolete();
3591 break;
3592 }
3593 }
3594
3595 // The previous loop may not find a matching EMCP method, but
3596 // that doesn't mean that we can optimize and not go any
3597 // further back in the PreviousVersion generations. The EMCP
3598 // method for this generation could have already been made obsolete,
3599 // but there still may be an older EMCP method that has not
3600 // been made obsolete.
3601 }
3602
3603 if (++local_count >= obsolete_method_count) {
3604 // no more obsolete methods so bail out now
3605 break;
3606 }
3607 }
3608 }
3609 }
3610 }
3611
3612 // Save the scratch_class as the previous version if any of the methods are running.
3613 // The previous_versions are used to set breakpoints in EMCP methods and they are
3614 // also used to clean MethodData links to redefined methods that are no longer running.
3615 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3616 int emcp_method_count) {
3617 assert(Thread::current()->is_VM_thread(),
3618 "only VMThread can add previous versions");
3619
3620 ResourceMark rm;
3621 log_trace(redefine, class, iklass, add)
3622 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3623
3624 // Clean out old previous versions for this class
3625 purge_previous_version_list();
3626
3627 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3628 // a previous redefinition may be made obsolete by this redefinition.
3629 Array<Method*>* old_methods = scratch_class->methods();
3630 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3631
3632 // If the constant pool for this previous version of the class
3633 // is not marked as being on the stack, then none of the methods
3634 // in this previous version of the class are on the stack so
3635 // we don't need to add this as a previous version.
3636 ConstantPool* cp_ref = scratch_class->constants();
3637 if (!cp_ref->on_stack()) {
3638 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3639 // For debugging purposes.
3640 scratch_class->set_is_scratch_class();
3641 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3642 return;
3643 }
3644
3645 if (emcp_method_count != 0) {
3646 // At least one method is still running, check for EMCP methods
3647 for (int i = 0; i < old_methods->length(); i++) {
3648 Method* old_method = old_methods->at(i);
3649 if (!old_method->is_obsolete() && old_method->on_stack()) {
3650 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3651 // we can add breakpoints for it.
3652
3653 // We set the method->on_stack bit during safepoints for class redefinition
3654 // and use this bit to set the is_running_emcp bit.
3655 // After the safepoint, the on_stack bit is cleared and the running emcp
3656 // method may exit. If so, we would set a breakpoint in a method that
3657 // is never reached, but this won't be noticeable to the programmer.
3658 old_method->set_running_emcp(true);
3659 log_trace(redefine, class, iklass, add)
3660 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3661 } else if (!old_method->is_obsolete()) {
3662 log_trace(redefine, class, iklass, add)
3663 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3664 }
3665 }
3666 }
3667
3668 // Add previous version if any methods are still running.
3669 // Set has_previous_version flag for processing during class unloading.
3670 _has_previous_versions = true;
3671 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3672 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3673 scratch_class->link_previous_versions(previous_versions());
3674 link_previous_versions(scratch_class());
3675 } // end add_previous_version()
3676
3677 #endif // INCLUDE_JVMTI
3678
3679 Method* InstanceKlass::method_with_idnum(int idnum) {
3680 Method* m = NULL;
3681 if (idnum < methods()->length()) {
3682 m = methods()->at(idnum);
3683 }
3684 if (m == NULL || m->method_idnum() != idnum) {
3685 for (int index = 0; index < methods()->length(); ++index) {
3686 m = methods()->at(index);
3687 if (m->method_idnum() == idnum) {
3688 return m;
3689 }
3690 }
3691 // None found, return null for the caller to handle.
3692 return NULL;
3693 }
3694 return m;
3695 }
3696
3697
3698 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3699 if (idnum >= methods()->length()) {
3700 return NULL;
3701 }
3702 Method* m = methods()->at(idnum);
3703 if (m != NULL && m->orig_method_idnum() == idnum) {
3704 return m;
3705 }
3706 // Obsolete method idnum does not match the original idnum
3707 for (int index = 0; index < methods()->length(); ++index) {
3708 m = methods()->at(index);
3709 if (m->orig_method_idnum() == idnum) {
3710 return m;
3711 }
3712 }
3713 // None found, return null for the caller to handle.
3714 return NULL;
3715 }
3716
3717
3718 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3719 InstanceKlass* holder = get_klass_version(version);
3720 if (holder == NULL) {
3721 return NULL; // The version of klass is gone, no method is found
3722 }
3723 Method* method = holder->method_with_orig_idnum(idnum);
3724 return method;
3725 }
3726
3727 #if INCLUDE_JVMTI
3728 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3729 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3730 // Ignore the archived class stream data
3731 return NULL;
3732 } else {
3733 return _cached_class_file;
3734 }
3735 }
3736
3737 jint InstanceKlass::get_cached_class_file_len() {
3738 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3739 }
3740
3741 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3742 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3743 }
3744
3745 #if INCLUDE_CDS
3746 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3747 assert(this->is_shared(), "class should be shared");
3748 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3749 return _cached_class_file;
3750 } else {
3751 return NULL;
3752 }
3753 }
3754 #endif
3755 #endif