1 /*
2 * Copyright (c) 1997, 2024, 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 "cds/aotClassInitializer.hpp"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/cdsEnumKlass.hpp"
30 #include "cds/classListWriter.hpp"
31 #include "cds/heapShared.hpp"
32 #include "cds/metaspaceShared.hpp"
33 #include "classfile/classFileParser.hpp"
34 #include "classfile/classFileStream.hpp"
35 #include "classfile/classLoader.hpp"
36 #include "classfile/classLoaderData.inline.hpp"
37 #include "classfile/javaClasses.hpp"
38 #include "classfile/moduleEntry.hpp"
39 #include "classfile/systemDictionary.hpp"
40 #include "classfile/systemDictionaryShared.hpp"
41 #include "classfile/verifier.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "code/codeCache.hpp"
45 #include "code/dependencyContext.hpp"
46 #include "compiler/compilationPolicy.hpp"
47 #include "compiler/compileBroker.hpp"
48 #include "gc/shared/collectedHeap.inline.hpp"
49 #include "interpreter/bytecodeStream.hpp"
50 #include "interpreter/oopMapCache.hpp"
51 #include "interpreter/rewriter.hpp"
52 #include "jvm.h"
53 #include "jvmtifiles/jvmti.h"
54 #include "logging/log.hpp"
55 #include "klass.inline.hpp"
56 #include "logging/logMessage.hpp"
57 #include "logging/logStream.hpp"
58 #include "memory/allocation.inline.hpp"
59 #include "memory/iterator.inline.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceClosure.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "memory/universe.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/constantPool.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/synchronizer.hpp"
93 #include "runtime/threads.hpp"
94 #include "services/classLoadingService.hpp"
95 #include "services/finalizerService.hpp"
96 #include "services/threadService.hpp"
97 #include "utilities/dtrace.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/macros.hpp"
100 #include "utilities/stringUtils.hpp"
101 #include "utilities/pair.hpp"
102 #ifdef COMPILER1
103 #include "c1/c1_Compiler.hpp"
104 #endif
105 #if INCLUDE_JFR
106 #include "jfr/jfrEvents.hpp"
107 #endif
108
109 #ifdef DTRACE_ENABLED
110
111
112 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
113 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
114 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
115 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
116 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
117 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
118 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
119 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
120 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
121 { \
122 char* data = nullptr; \
123 int len = 0; \
124 Symbol* clss_name = name(); \
125 if (clss_name != nullptr) { \
126 data = (char*)clss_name->bytes(); \
127 len = clss_name->utf8_length(); \
128 } \
129 HOTSPOT_CLASS_INITIALIZATION_##type( \
130 data, len, (void*)class_loader(), thread_type); \
131 }
132
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
134 { \
135 char* data = nullptr; \
136 int len = 0; \
137 Symbol* clss_name = name(); \
138 if (clss_name != nullptr) { \
139 data = (char*)clss_name->bytes(); \
140 len = clss_name->utf8_length(); \
141 } \
142 HOTSPOT_CLASS_INITIALIZATION_##type( \
143 data, len, (void*)class_loader(), thread_type, wait); \
144 }
145
146 #else // ndef DTRACE_ENABLED
147
148 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
149 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
150
151 #endif // ndef DTRACE_ENABLED
152
153 bool InstanceKlass::_finalization_enabled = true;
154
155 static inline bool is_class_loader(const Symbol* class_name,
156 const ClassFileParser& parser) {
157 assert(class_name != nullptr, "invariant");
158
159 if (class_name == vmSymbols::java_lang_ClassLoader()) {
160 return true;
161 }
162
163 if (vmClasses::ClassLoader_klass_loaded()) {
164 const Klass* const super_klass = parser.super_klass();
165 if (super_klass != nullptr) {
166 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
167 return true;
168 }
169 }
170 }
171 return false;
172 }
173
174 static inline bool is_stack_chunk_class(const Symbol* class_name,
175 const ClassLoaderData* loader_data) {
176 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
177 loader_data->is_the_null_class_loader_data());
178 }
179
180 // private: called to verify that k is a static member of this nest.
181 // We know that k is an instance class in the same package and hence the
182 // same classloader.
183 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
184 assert(!is_hidden(), "unexpected hidden class");
185 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
186 if (log_is_enabled(Trace, class, nestmates)) {
187 ResourceMark rm(current);
188 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
189 k->external_name(), this->external_name());
190 }
191 return false;
192 }
193
194 if (log_is_enabled(Trace, class, nestmates)) {
195 ResourceMark rm(current);
196 log_trace(class, nestmates)("Checking nest membership of %s in %s",
197 k->external_name(), this->external_name());
198 }
199
200 // Check for the named class in _nest_members.
201 // We don't resolve, or load, any classes.
202 for (int i = 0; i < _nest_members->length(); i++) {
203 int cp_index = _nest_members->at(i);
204 Symbol* name = _constants->klass_name_at(cp_index);
205 if (name == k->name()) {
206 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
207 return true;
208 }
209 }
210 log_trace(class, nestmates)("- class is NOT a nest member!");
211 return false;
212 }
213
214 // Called to verify that k is a permitted subclass of this class
215 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
216 Thread* current = Thread::current();
217 assert(k != nullptr, "sanity check");
218 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
219 "unexpected empty _permitted_subclasses array");
220
221 if (log_is_enabled(Trace, class, sealed)) {
222 ResourceMark rm(current);
223 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
224 k->external_name(), this->external_name());
225 }
226
227 // Check that the class and its super are in the same module.
228 if (k->module() != this->module()) {
229 ResourceMark rm(current);
230 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
231 k->external_name(), this->external_name());
232 return false;
233 }
234
235 if (!k->is_public() && !is_same_class_package(k)) {
236 ResourceMark rm(current);
237 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
238 k->external_name(), this->external_name());
239 return false;
240 }
241
242 for (int i = 0; i < _permitted_subclasses->length(); i++) {
243 int cp_index = _permitted_subclasses->at(i);
244 Symbol* name = _constants->klass_name_at(cp_index);
245 if (name == k->name()) {
246 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
247 return true;
248 }
249 }
250 log_trace(class, sealed)("- class is NOT a permitted subclass!");
251 return false;
252 }
253
254 // Return nest-host class, resolving, validating and saving it if needed.
255 // In cases where this is called from a thread that cannot do classloading
256 // (such as a native JIT thread) then we simply return null, which in turn
257 // causes the access check to return false. Such code will retry the access
258 // from a more suitable environment later. Otherwise the _nest_host is always
259 // set once this method returns.
260 // Any errors from nest-host resolution must be preserved so they can be queried
261 // from higher-level access checking code, and reported as part of access checking
262 // exceptions.
263 // VirtualMachineErrors are propagated with a null return.
264 // Under any conditions where the _nest_host can be set to non-null the resulting
265 // value of it and, if applicable, the nest host resolution/validation error,
266 // are idempotent.
267 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
268 InstanceKlass* nest_host_k = _nest_host;
269 if (nest_host_k != nullptr) {
270 return nest_host_k;
271 }
272
273 ResourceMark rm(THREAD);
274
275 // need to resolve and save our nest-host class.
276 if (_nest_host_index != 0) { // we have a real nest_host
277 // Before trying to resolve check if we're in a suitable context
278 bool can_resolve = THREAD->can_call_java();
279 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
280 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
281 this->external_name());
282 return nullptr; // sentinel to say "try again from a different context"
283 }
284
285 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
286 this->external_name(),
287 _constants->klass_name_at(_nest_host_index)->as_C_string());
288
289 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
290 if (HAS_PENDING_EXCEPTION) {
291 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
292 return nullptr; // propagate VMEs
293 }
294 stringStream ss;
295 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
296 ss.print("Nest host resolution of %s with host %s failed: ",
297 this->external_name(), target_host_class);
298 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
299 const char* msg = ss.as_string(true /* on C-heap */);
300 constantPoolHandle cph(THREAD, constants());
301 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
302 CLEAR_PENDING_EXCEPTION;
303
304 log_trace(class, nestmates)("%s", msg);
305 } else {
306 // A valid nest-host is an instance class in the current package that lists this
307 // class as a nest member. If any of these conditions are not met the class is
308 // its own nest-host.
309 const char* error = nullptr;
310
311 // JVMS 5.4.4 indicates package check comes first
312 if (is_same_class_package(k)) {
313 // Now check actual membership. We can't be a member if our "host" is
314 // not an instance class.
315 if (k->is_instance_klass()) {
316 nest_host_k = InstanceKlass::cast(k);
317 bool is_member = nest_host_k->has_nest_member(THREAD, this);
318 if (is_member) {
319 _nest_host = nest_host_k; // save resolved nest-host value
320
321 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
322 this->external_name(), k->external_name());
323 return nest_host_k;
324 } else {
325 error = "current type is not listed as a nest member";
326 }
327 } else {
328 error = "host is not an instance class";
329 }
330 } else {
331 error = "types are in different packages";
332 }
333
334 // something went wrong, so record what and log it
335 {
336 stringStream ss;
337 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
338 this->external_name(),
339 this->class_loader_data()->loader_name_and_id(),
340 k->external_name(),
341 k->class_loader_data()->loader_name_and_id(),
342 error);
343 const char* msg = ss.as_string(true /* on C-heap */);
344 constantPoolHandle cph(THREAD, constants());
345 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
346 log_trace(class, nestmates)("%s", msg);
347 }
348 }
349 } else {
350 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
351 this->external_name());
352 }
353
354 // Either not in an explicit nest, or else an error occurred, so
355 // the nest-host is set to `this`. Any thread that sees this assignment
356 // will also see any setting of nest_host_error(), if applicable.
357 return (_nest_host = this);
358 }
359
360 // Dynamic nest member support: set this class's nest host to the given class.
361 // This occurs as part of the class definition, as soon as the instanceKlass
362 // has been created and doesn't require further resolution. The code:
363 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
364 // results in:
365 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
366 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
367 // We also know the "host" is a valid nest-host in the same package so we can
368 // assert some of those facts.
369 void InstanceKlass::set_nest_host(InstanceKlass* host) {
370 assert(is_hidden(), "must be a hidden class");
371 assert(host != nullptr, "null nest host specified");
372 assert(_nest_host == nullptr, "current class has resolved nest-host");
373 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
374 nest_host_error());
375 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
376 (host->_nest_host == host), "proposed host is not a valid nest-host");
377 // Can't assert this as package is not set yet:
378 // assert(is_same_class_package(host), "proposed host is in wrong package");
379
380 if (log_is_enabled(Trace, class, nestmates)) {
381 ResourceMark rm;
382 const char* msg = "";
383 // a hidden class does not expect a statically defined nest-host
384 if (_nest_host_index > 0) {
385 msg = "(the NestHost attribute in the current class is ignored)";
386 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
387 msg = "(the NestMembers attribute in the current class is ignored)";
388 }
389 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
390 this->external_name(),
391 host->external_name(),
392 msg);
393 }
394 // set dynamic nest host
395 _nest_host = host;
396 // Record dependency to keep nest host from being unloaded before this class.
397 ClassLoaderData* this_key = class_loader_data();
398 assert(this_key != nullptr, "sanity");
399 this_key->record_dependency(host);
400 }
401
402 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
403 // or we are k's nest_host - all of which is covered by comparing the two
404 // resolved_nest_hosts.
405 // Any exceptions (i.e. VMEs) are propagated.
406 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
407
408 assert(this != k, "this should be handled by higher-level code");
409
410 // Per JVMS 5.4.4 we first resolve and validate the current class, then
411 // the target class k.
412
413 InstanceKlass* cur_host = nest_host(CHECK_false);
414 if (cur_host == nullptr) {
415 return false;
416 }
417
418 Klass* k_nest_host = k->nest_host(CHECK_false);
419 if (k_nest_host == nullptr) {
420 return false;
421 }
422
423 bool access = (cur_host == k_nest_host);
424
425 ResourceMark rm(THREAD);
426 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
427 this->external_name(),
428 access ? "" : "NOT ",
429 k->external_name());
430 return access;
431 }
432
433 const char* InstanceKlass::nest_host_error() {
434 if (_nest_host_index == 0) {
435 return nullptr;
436 } else {
437 constantPoolHandle cph(Thread::current(), constants());
438 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
439 }
440 }
441
442 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
443 bool use_class_space, TRAPS) throw() {
444 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
445 }
446
447 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
448 const int size = InstanceKlass::size(parser.vtable_size(),
449 parser.itable_size(),
450 nonstatic_oop_map_size(parser.total_oop_map_count()),
451 parser.is_interface());
452
453 const Symbol* const class_name = parser.class_name();
454 assert(class_name != nullptr, "invariant");
455 ClassLoaderData* loader_data = parser.loader_data();
456 assert(loader_data != nullptr, "invariant");
457
458 InstanceKlass* ik;
459 const bool use_class_space = parser.klass_needs_narrow_id();
460
461 // Allocation
462 if (parser.is_instance_ref_klass()) {
463 // java.lang.ref.Reference
464 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
465 } else if (class_name == vmSymbols::java_lang_Class()) {
466 // mirror - java.lang.Class
467 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
468 } else if (is_stack_chunk_class(class_name, loader_data)) {
469 // stack chunk
470 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
471 } else if (is_class_loader(class_name, parser)) {
472 // class loader - java.lang.ClassLoader
473 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
474 } else {
475 // normal
476 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
477 }
478
479 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
480 assert(CompressedKlassPointers::is_encodable(ik),
481 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
482 }
483
484 // Check for pending exception before adding to the loader data and incrementing
485 // class count. Can get OOM here.
486 if (HAS_PENDING_EXCEPTION) {
487 return nullptr;
488 }
489
490 return ik;
491 }
492
493
494 // copy method ordering from resource area to Metaspace
495 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
496 if (m != nullptr) {
497 // allocate a new array and copy contents (memcpy?)
498 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
499 for (int i = 0; i < m->length(); i++) {
500 _method_ordering->at_put(i, m->at(i));
501 }
502 } else {
503 _method_ordering = Universe::the_empty_int_array();
504 }
505 }
506
507 // create a new array of vtable_indices for default methods
508 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
509 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
510 assert(default_vtable_indices() == nullptr, "only create once");
511 set_default_vtable_indices(vtable_indices);
512 return vtable_indices;
513 }
514
515
516 InstanceKlass::InstanceKlass() {
517 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
518 }
519
520 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
521 Klass(kind),
522 _nest_members(nullptr),
523 _nest_host(nullptr),
524 _permitted_subclasses(nullptr),
525 _record_components(nullptr),
526 _static_field_size(parser.static_field_size()),
527 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
528 _itable_len(parser.itable_size()),
529 _nest_host_index(0),
530 _init_state(allocated),
531 _reference_type(reference_type),
532 _init_thread(nullptr)
533 {
534 set_vtable_length(parser.vtable_size());
535 set_access_flags(parser.access_flags());
536 if (parser.is_hidden()) set_is_hidden();
537 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
538 false));
539
540 assert(nullptr == _methods, "underlying memory not zeroed?");
541 assert(is_instance_klass(), "is layout incorrect?");
542 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
543 }
544
545 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
546 Array<Method*>* methods) {
547 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
548 !methods->is_shared()) {
549 for (int i = 0; i < methods->length(); i++) {
550 Method* method = methods->at(i);
551 if (method == nullptr) continue; // maybe null if error processing
552 // Only want to delete methods that are not executing for RedefineClasses.
553 // The previous version will point to them so they're not totally dangling
554 assert (!method->on_stack(), "shouldn't be called with methods on stack");
555 MetadataFactory::free_metadata(loader_data, method);
556 }
557 MetadataFactory::free_array<Method*>(loader_data, methods);
558 }
559 }
560
561 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
562 const Klass* super_klass,
563 Array<InstanceKlass*>* local_interfaces,
564 Array<InstanceKlass*>* transitive_interfaces) {
565 // Only deallocate transitive interfaces if not empty, same as super class
566 // or same as local interfaces. See code in parseClassFile.
567 Array<InstanceKlass*>* ti = transitive_interfaces;
568 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
569 // check that the interfaces don't come from super class
570 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
571 InstanceKlass::cast(super_klass)->transitive_interfaces();
572 if (ti != sti && ti != nullptr && !ti->is_shared()) {
573 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
574 }
575 }
576
577 // local interfaces can be empty
578 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
579 local_interfaces != nullptr && !local_interfaces->is_shared()) {
580 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
581 }
582 }
583
584 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
585 Array<RecordComponent*>* record_components) {
586 if (record_components != nullptr && !record_components->is_shared()) {
587 for (int i = 0; i < record_components->length(); i++) {
588 RecordComponent* record_component = record_components->at(i);
589 MetadataFactory::free_metadata(loader_data, record_component);
590 }
591 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
592 }
593 }
594
595 // This function deallocates the metadata and C heap pointers that the
596 // InstanceKlass points to.
597 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
598 // Orphan the mirror first, CMS thinks it's still live.
599 if (java_mirror() != nullptr) {
600 java_lang_Class::set_klass(java_mirror(), nullptr);
601 }
602
603 // Also remove mirror from handles
604 loader_data->remove_handle(_java_mirror);
605
606 // Need to take this class off the class loader data list.
607 loader_data->remove_class(this);
608
609 // The array_klass for this class is created later, after error handling.
610 // For class redefinition, we keep the original class so this scratch class
611 // doesn't have an array class. Either way, assert that there is nothing
612 // to deallocate.
613 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
614
615 // Release C heap allocated data that this points to, which includes
616 // reference counting symbol names.
617 // Can't release the constant pool or MethodData C heap data here because the constant
618 // pool can be deallocated separately from the InstanceKlass for default methods and
619 // redefine classes. MethodData can also be released separately.
620 release_C_heap_structures(/* release_sub_metadata */ false);
621
622 deallocate_methods(loader_data, methods());
623 set_methods(nullptr);
624
625 deallocate_record_components(loader_data, record_components());
626 set_record_components(nullptr);
627
628 if (method_ordering() != nullptr &&
629 method_ordering() != Universe::the_empty_int_array() &&
630 !method_ordering()->is_shared()) {
631 MetadataFactory::free_array<int>(loader_data, method_ordering());
632 }
633 set_method_ordering(nullptr);
634
635 // default methods can be empty
636 if (default_methods() != nullptr &&
637 default_methods() != Universe::the_empty_method_array() &&
638 !default_methods()->is_shared()) {
639 MetadataFactory::free_array<Method*>(loader_data, default_methods());
640 }
641 // Do NOT deallocate the default methods, they are owned by superinterfaces.
642 set_default_methods(nullptr);
643
644 // default methods vtable indices can be empty
645 if (default_vtable_indices() != nullptr &&
646 !default_vtable_indices()->is_shared()) {
647 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
648 }
649 set_default_vtable_indices(nullptr);
650
651
652 // This array is in Klass, but remove it with the InstanceKlass since
653 // this place would be the only caller and it can share memory with transitive
654 // interfaces.
655 if (secondary_supers() != nullptr &&
656 secondary_supers() != Universe::the_empty_klass_array() &&
657 // see comments in compute_secondary_supers about the following cast
658 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
659 !secondary_supers()->is_shared()) {
660 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
661 }
662 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
663
664 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
665 set_transitive_interfaces(nullptr);
666 set_local_interfaces(nullptr);
667
668 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
669 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
670 }
671 set_fieldinfo_stream(nullptr);
672
673 if (fields_status() != nullptr && !fields_status()->is_shared()) {
674 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
675 }
676 set_fields_status(nullptr);
677
678 // If a method from a redefined class is using this constant pool, don't
679 // delete it, yet. The new class's previous version will point to this.
680 if (constants() != nullptr) {
681 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
682 if (!constants()->is_shared()) {
683 MetadataFactory::free_metadata(loader_data, constants());
684 }
685 // Delete any cached resolution errors for the constant pool
686 SystemDictionary::delete_resolution_error(constants());
687
688 set_constants(nullptr);
689 }
690
691 if (inner_classes() != nullptr &&
692 inner_classes() != Universe::the_empty_short_array() &&
693 !inner_classes()->is_shared()) {
694 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
695 }
696 set_inner_classes(nullptr);
697
698 if (nest_members() != nullptr &&
699 nest_members() != Universe::the_empty_short_array() &&
700 !nest_members()->is_shared()) {
701 MetadataFactory::free_array<jushort>(loader_data, nest_members());
702 }
703 set_nest_members(nullptr);
704
705 if (permitted_subclasses() != nullptr &&
706 permitted_subclasses() != Universe::the_empty_short_array() &&
707 !permitted_subclasses()->is_shared()) {
708 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
709 }
710 set_permitted_subclasses(nullptr);
711
712 // We should deallocate the Annotations instance if it's not in shared spaces.
713 if (annotations() != nullptr && !annotations()->is_shared()) {
714 MetadataFactory::free_metadata(loader_data, annotations());
715 }
716 set_annotations(nullptr);
717
718 SystemDictionaryShared::handle_class_unloading(this);
719
720 #if INCLUDE_CDS_JAVA_HEAP
721 if (CDSConfig::is_dumping_heap()) {
722 HeapShared::remove_scratch_objects(this);
723 }
724 #endif
725 }
726
727 bool InstanceKlass::is_record() const {
728 return _record_components != nullptr &&
729 is_final() &&
730 java_super() == vmClasses::Record_klass();
731 }
732
733 bool InstanceKlass::is_sealed() const {
734 return _permitted_subclasses != nullptr &&
735 _permitted_subclasses != Universe::the_empty_short_array();
736 }
737
738 // JLS 8.9: An enum class is either implicitly final and derives
739 // from java.lang.Enum, or else is implicitly sealed to its
740 // anonymous subclasses. This query detects both kinds.
741 // It does not validate the finality or
742 // sealing conditions: it merely checks for a super of Enum.
743 // This is sufficient for recognizing well-formed enums.
744 bool InstanceKlass::is_enum_subclass() const {
745 InstanceKlass* s = java_super();
746 return (s == vmClasses::Enum_klass() ||
747 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
748 }
749
750 bool InstanceKlass::should_be_initialized() const {
751 return !is_initialized();
752 }
753
754 klassItable InstanceKlass::itable() const {
755 return klassItable(const_cast<InstanceKlass*>(this));
756 }
757
758 // JVMTI spec thinks there are signers and protection domain in the
759 // instanceKlass. These accessors pretend these fields are there.
760 // The hprof specification also thinks these fields are in InstanceKlass.
761 oop InstanceKlass::protection_domain() const {
762 // return the protection_domain from the mirror
763 return java_lang_Class::protection_domain(java_mirror());
764 }
765
766 objArrayOop InstanceKlass::signers() const {
767 // return the signers from the mirror
768 return java_lang_Class::signers(java_mirror());
769 }
770
771 oop InstanceKlass::init_lock() const {
772 // return the init lock from the mirror
773 oop lock = java_lang_Class::init_lock(java_mirror());
774 // Prevent reordering with any access of initialization state
775 OrderAccess::loadload();
776 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
777 "only fully initialized state can have a null lock");
778 return lock;
779 }
780
781 // Set the initialization lock to null so the object can be GC'ed. Any racing
782 // threads to get this lock will see a null lock and will not lock.
783 // That's okay because they all check for initialized state after getting
784 // the lock and return.
785 void InstanceKlass::fence_and_clear_init_lock() {
786 // make sure previous stores are all done, notably the init_state.
787 OrderAccess::storestore();
788 java_lang_Class::clear_init_lock(java_mirror());
789 assert(!is_not_initialized(), "class must be initialized now");
790 }
791
792
793 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
794 // process. The step comments refers to the procedure described in that section.
795 // Note: implementation moved to static method to expose the this pointer.
796 void InstanceKlass::initialize(TRAPS) {
797 if (this->should_be_initialized()) {
798 initialize_impl(CHECK);
799 // Note: at this point the class may be initialized
800 // OR it may be in the state of being initialized
801 // in case of recursive initialization!
802 } else {
803 assert(is_initialized(), "sanity check");
804 }
805 }
806
807 #ifdef ASSERT
808 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
809 assert(has_aot_initialized_mirror(), "must be");
810
811 InstanceKlass* s = java_super();
812 if (s != nullptr) {
813 DEBUG_ONLY(ResourceMark rm);
814 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
815 s->external_name(), external_name());
816 s->assert_no_clinit_will_run_for_aot_initialized_class();
817 }
818
819 Array<InstanceKlass*>* interfaces = local_interfaces();
820 int len = interfaces->length();
821 for (int i = 0; i < len; i++) {
822 InstanceKlass* intf = interfaces->at(i);
823 if (!intf->is_initialized()) {
824 ResourceMark rm;
825 // Note: an interface needs to be marked as is_initialized() only if
826 // - it has a <clinit>
827 // - it has declared a default method.
828 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
829 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
830 intf->external_name(), external_name());
831 }
832 }
833 }
834 #endif
835
836 #if INCLUDE_CDS
837 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
838 assert(has_aot_initialized_mirror(), "must be");
839 assert(CDSConfig::is_loading_heap(), "must be");
840 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
841 assert_no_clinit_will_run_for_aot_initialized_class();
842
843 if (is_initialized()) {
844 return;
845 }
846
847 if (log_is_enabled(Info, cds, init)) {
848 ResourceMark rm;
849 log_info(cds, init)("%s (aot-inited)", external_name());
850 }
851
852 link_class(CHECK);
853
854 #ifdef ASSERT
855 {
856 Handle h_init_lock(THREAD, init_lock());
857 ObjectLocker ol(h_init_lock, THREAD);
858 assert(!is_initialized(), "sanity");
859 assert(!is_being_initialized(), "sanity");
860 assert(!is_in_error_state(), "sanity");
861 }
862 #endif
863
864 set_init_thread(THREAD);
865 AOTClassInitializer::call_runtime_setup(THREAD, this);
866 set_initialization_state_and_notify(fully_initialized, CHECK);
867 }
868 #endif
869
870 bool InstanceKlass::verify_code(TRAPS) {
871 // 1) Verify the bytecodes
872 return Verifier::verify(this, should_verify_class(), THREAD);
873 }
874
875 void InstanceKlass::link_class(TRAPS) {
876 assert(is_loaded(), "must be loaded");
877 if (!is_linked()) {
878 link_class_impl(CHECK);
879 }
880 }
881
882 // Called to verify that a class can link during initialization, without
883 // throwing a VerifyError.
884 bool InstanceKlass::link_class_or_fail(TRAPS) {
885 assert(is_loaded(), "must be loaded");
886 if (!is_linked()) {
887 link_class_impl(CHECK_false);
888 }
889 return is_linked();
890 }
891
892 bool InstanceKlass::link_class_impl(TRAPS) {
893 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
894 // This is for CDS static dump only -- we use the in_error_state to indicate that
895 // the class has failed verification. Throwing the NoClassDefFoundError here is just
896 // a convenient way to stop repeat attempts to verify the same (bad) class.
897 //
898 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
899 // if we are executing Java code. This is not a problem for CDS dumping phase since
900 // it doesn't execute any Java code.
901 ResourceMark rm(THREAD);
902 Exceptions::fthrow(THREAD_AND_LOCATION,
903 vmSymbols::java_lang_NoClassDefFoundError(),
904 "Class %s, or one of its supertypes, failed class initialization",
905 external_name());
906 return false;
907 }
908 // return if already verified
909 if (is_linked()) {
910 return true;
911 }
912
913 // Timing
914 // timer handles recursion
915 JavaThread* jt = THREAD;
916
917 // link super class before linking this class
918 Klass* super_klass = super();
919 if (super_klass != nullptr) {
920 if (super_klass->is_interface()) { // check if super class is an interface
921 ResourceMark rm(THREAD);
922 Exceptions::fthrow(
923 THREAD_AND_LOCATION,
924 vmSymbols::java_lang_IncompatibleClassChangeError(),
925 "class %s has interface %s as super class",
926 external_name(),
927 super_klass->external_name()
928 );
929 return false;
930 }
931
932 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
933 ik_super->link_class_impl(CHECK_false);
934 }
935
936 // link all interfaces implemented by this class before linking this class
937 Array<InstanceKlass*>* interfaces = local_interfaces();
938 int num_interfaces = interfaces->length();
939 for (int index = 0; index < num_interfaces; index++) {
940 InstanceKlass* interk = interfaces->at(index);
941 interk->link_class_impl(CHECK_false);
942 }
943
944 // in case the class is linked in the process of linking its superclasses
945 if (is_linked()) {
946 return true;
947 }
948
949 // trace only the link time for this klass that includes
950 // the verification time
951 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
952 ClassLoader::perf_class_link_selftime(),
953 ClassLoader::perf_classes_linked(),
954 jt->get_thread_stat()->perf_recursion_counts_addr(),
955 jt->get_thread_stat()->perf_timers_addr(),
956 PerfClassTraceTime::CLASS_LINK);
957
958 // verification & rewriting
959 {
960 HandleMark hm(THREAD);
961 Handle h_init_lock(THREAD, init_lock());
962 ObjectLocker ol(h_init_lock, jt);
963 // rewritten will have been set if loader constraint error found
964 // on an earlier link attempt
965 // don't verify or rewrite if already rewritten
966 //
967
968 if (!is_linked()) {
969 if (!is_rewritten()) {
970 if (is_shared()) {
971 assert(!verified_at_dump_time(), "must be");
972 }
973 {
974 bool verify_ok = verify_code(THREAD);
975 if (!verify_ok) {
976 return false;
977 }
978 }
979
980 // Just in case a side-effect of verify linked this class already
981 // (which can sometimes happen since the verifier loads classes
982 // using custom class loaders, which are free to initialize things)
983 if (is_linked()) {
984 return true;
985 }
986
987 // also sets rewritten
988 rewrite_class(CHECK_false);
989 } else if (is_shared()) {
990 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
991 }
992
993 // relocate jsrs and link methods after they are all rewritten
994 link_methods(CHECK_false);
995
996 // Initialize the vtable and interface table after
997 // methods have been rewritten since rewrite may
998 // fabricate new Method*s.
999 // also does loader constraint checking
1000 //
1001 // initialize_vtable and initialize_itable need to be rerun
1002 // for a shared class if
1003 // 1) the class is loaded by custom class loader or
1004 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1005 // 3) the class was not verified during dump time
1006 bool need_init_table = true;
1007 if (is_shared() && verified_at_dump_time() &&
1008 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1009 need_init_table = false;
1010 }
1011 if (need_init_table) {
1012 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1013 itable().initialize_itable_and_check_constraints(CHECK_false);
1014 }
1015 #ifdef ASSERT
1016 vtable().verify(tty, true);
1017 // In case itable verification is ever added.
1018 // itable().verify(tty, true);
1019 #endif
1020 if (Universe::is_fully_initialized()) {
1021 DeoptimizationScope deopt_scope;
1022 {
1023 // Now mark all code that assumes the class is not linked.
1024 // Set state under the Compile_lock also.
1025 MutexLocker ml(THREAD, Compile_lock);
1026
1027 set_init_state(linked);
1028 CodeCache::mark_dependents_on(&deopt_scope, this);
1029 }
1030 // Perform the deopt handshake outside Compile_lock.
1031 deopt_scope.deoptimize_marked();
1032 } else {
1033 set_init_state(linked);
1034 }
1035 if (JvmtiExport::should_post_class_prepare()) {
1036 JvmtiExport::post_class_prepare(THREAD, this);
1037 }
1038 }
1039 }
1040 return true;
1041 }
1042
1043 // Rewrite the byte codes of all of the methods of a class.
1044 // The rewriter must be called exactly once. Rewriting must happen after
1045 // verification but before the first method of the class is executed.
1046 void InstanceKlass::rewrite_class(TRAPS) {
1047 assert(is_loaded(), "must be loaded");
1048 if (is_rewritten()) {
1049 assert(is_shared(), "rewriting an unshared class?");
1050 return;
1051 }
1052 Rewriter::rewrite(this, CHECK);
1053 set_rewritten();
1054 }
1055
1056 // Now relocate and link method entry points after class is rewritten.
1057 // This is outside is_rewritten flag. In case of an exception, it can be
1058 // executed more than once.
1059 void InstanceKlass::link_methods(TRAPS) {
1060 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1061
1062 int len = methods()->length();
1063 for (int i = len-1; i >= 0; i--) {
1064 methodHandle m(THREAD, methods()->at(i));
1065
1066 // Set up method entry points for compiler and interpreter .
1067 m->link_method(m, CHECK);
1068 }
1069 }
1070
1071 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1072 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1073 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1074 for (int i = 0; i < local_interfaces()->length(); ++i) {
1075 InstanceKlass* ik = local_interfaces()->at(i);
1076
1077 // Initialization is depth first search ie. we start with top of the inheritance tree
1078 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1079 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1080 if (ik->has_nonstatic_concrete_methods()) {
1081 ik->initialize_super_interfaces(CHECK);
1082 }
1083
1084 // Only initialize() interfaces that "declare" concrete methods.
1085 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1086 ik->initialize(CHECK);
1087 }
1088 }
1089 }
1090
1091 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1092 static InitializationErrorTable* _initialization_error_table;
1093
1094 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1095 // Create the same exception with a message indicating the thread name,
1096 // and the StackTraceElements.
1097 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1098 ResourceMark rm(current);
1099 if (init_error.is_null()) {
1100 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1101
1102 // We failed to create the new exception, most likely due to either out-of-memory or
1103 // a stackoverflow error. If the original exception was either of those then we save
1104 // the shared, pre-allocated, stackless, instance of that exception.
1105 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1106 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1107 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1108 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1109 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1110 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1111 } else {
1112 return;
1113 }
1114 }
1115
1116 MutexLocker ml(current, ClassInitError_lock);
1117 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1118 bool created;
1119 if (_initialization_error_table == nullptr) {
1120 _initialization_error_table = new (mtClass) InitializationErrorTable();
1121 }
1122 _initialization_error_table->put_if_absent(this, elem, &created);
1123 assert(created, "Initialization is single threaded");
1124 log_trace(class, init)("Initialization error added for class %s", external_name());
1125 }
1126
1127 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1128 MutexLocker ml(current, ClassInitError_lock);
1129 if (_initialization_error_table == nullptr) {
1130 return nullptr;
1131 }
1132 OopHandle* h = _initialization_error_table->get(this);
1133 return (h != nullptr) ? h->resolve() : nullptr;
1134 }
1135
1136 // Need to remove entries for unloaded classes.
1137 void InstanceKlass::clean_initialization_error_table() {
1138 struct InitErrorTableCleaner {
1139 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1140 if (!ik->is_loader_alive()) {
1141 h.release(Universe::vm_global());
1142 return true;
1143 } else {
1144 return false;
1145 }
1146 }
1147 };
1148
1149 assert_locked_or_safepoint(ClassInitError_lock);
1150 InitErrorTableCleaner cleaner;
1151 if (_initialization_error_table != nullptr) {
1152 _initialization_error_table->unlink(&cleaner);
1153 }
1154 }
1155
1156 void InstanceKlass::initialize_impl(TRAPS) {
1157 HandleMark hm(THREAD);
1158
1159 // Make sure klass is linked (verified) before initialization
1160 // A class could already be verified, since it has been reflected upon.
1161 link_class(CHECK);
1162
1163 DTRACE_CLASSINIT_PROBE(required, -1);
1164
1165 bool wait = false;
1166
1167 JavaThread* jt = THREAD;
1168
1169 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1170
1171 // refer to the JVM book page 47 for description of steps
1172 // Step 1
1173 {
1174 Handle h_init_lock(THREAD, init_lock());
1175 ObjectLocker ol(h_init_lock, jt);
1176
1177 // Step 2
1178 // If we were to use wait() instead of waitInterruptibly() then
1179 // we might end up throwing IE from link/symbol resolution sites
1180 // that aren't expected to throw. This would wreak havoc. See 6320309.
1181 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1182 if (debug_logging_enabled) {
1183 ResourceMark rm(jt);
1184 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1185 jt->name(), external_name(), init_thread_name());
1186 }
1187 wait = true;
1188 jt->set_class_to_be_initialized(this);
1189 ol.wait_uninterruptibly(jt);
1190 jt->set_class_to_be_initialized(nullptr);
1191 }
1192
1193 // Step 3
1194 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1195 if (debug_logging_enabled) {
1196 ResourceMark rm(jt);
1197 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1198 jt->name(), external_name());
1199 }
1200 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1201 return;
1202 }
1203
1204 // Step 4
1205 if (is_initialized()) {
1206 if (debug_logging_enabled) {
1207 ResourceMark rm(jt);
1208 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1209 jt->name(), external_name());
1210 }
1211 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1212 return;
1213 }
1214
1215 // Step 5
1216 if (is_in_error_state()) {
1217 if (debug_logging_enabled) {
1218 ResourceMark rm(jt);
1219 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1220 jt->name(), external_name());
1221 }
1222
1223 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1224 ResourceMark rm(THREAD);
1225 Handle cause(THREAD, get_initialization_error(THREAD));
1226
1227 stringStream ss;
1228 ss.print("Could not initialize class %s", external_name());
1229 if (cause.is_null()) {
1230 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1231 } else {
1232 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1233 ss.as_string(), cause);
1234 }
1235 } else {
1236
1237 // Step 6
1238 set_init_state(being_initialized);
1239 set_init_thread(jt);
1240 if (debug_logging_enabled) {
1241 ResourceMark rm(jt);
1242 log_debug(class, init)("Thread \"%s\" is initializing %s",
1243 jt->name(), external_name());
1244 }
1245 }
1246 }
1247
1248 // Step 7
1249 // Next, if C is a class rather than an interface, initialize it's super class and super
1250 // interfaces.
1251 if (!is_interface()) {
1252 Klass* super_klass = super();
1253 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1254 super_klass->initialize(THREAD);
1255 }
1256 // If C implements any interface that declares a non-static, concrete method,
1257 // the initialization of C triggers initialization of its super interfaces.
1258 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1259 // having a superinterface that declares, non-static, concrete methods
1260 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1261 initialize_super_interfaces(THREAD);
1262 }
1263
1264 // If any exceptions, complete abruptly, throwing the same exception as above.
1265 if (HAS_PENDING_EXCEPTION) {
1266 Handle e(THREAD, PENDING_EXCEPTION);
1267 CLEAR_PENDING_EXCEPTION;
1268 {
1269 EXCEPTION_MARK;
1270 add_initialization_error(THREAD, e);
1271 // Locks object, set state, and notify all waiting threads
1272 set_initialization_state_and_notify(initialization_error, THREAD);
1273 CLEAR_PENDING_EXCEPTION;
1274 }
1275 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1276 THROW_OOP(e());
1277 }
1278 }
1279
1280
1281 // Step 8
1282 {
1283 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1284 if (class_initializer() != nullptr) {
1285 // Timer includes any side effects of class initialization (resolution,
1286 // etc), but not recursive entry into call_class_initializer().
1287 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1288 ClassLoader::perf_class_init_selftime(),
1289 ClassLoader::perf_classes_inited(),
1290 jt->get_thread_stat()->perf_recursion_counts_addr(),
1291 jt->get_thread_stat()->perf_timers_addr(),
1292 PerfClassTraceTime::CLASS_CLINIT);
1293 call_class_initializer(THREAD);
1294 } else {
1295 // The elapsed time is so small it's not worth counting.
1296 if (UsePerfData) {
1297 ClassLoader::perf_classes_inited()->inc();
1298 }
1299 call_class_initializer(THREAD);
1300 }
1301 }
1302
1303 // Step 9
1304 if (!HAS_PENDING_EXCEPTION) {
1305 set_initialization_state_and_notify(fully_initialized, CHECK);
1306 debug_only(vtable().verify(tty, true);)
1307 }
1308 else {
1309 // Step 10 and 11
1310 Handle e(THREAD, PENDING_EXCEPTION);
1311 CLEAR_PENDING_EXCEPTION;
1312 // JVMTI has already reported the pending exception
1313 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1314 JvmtiExport::clear_detected_exception(jt);
1315 {
1316 EXCEPTION_MARK;
1317 add_initialization_error(THREAD, e);
1318 set_initialization_state_and_notify(initialization_error, THREAD);
1319 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1320 // JVMTI has already reported the pending exception
1321 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1322 JvmtiExport::clear_detected_exception(jt);
1323 }
1324 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1325 if (e->is_a(vmClasses::Error_klass())) {
1326 THROW_OOP(e());
1327 } else {
1328 JavaCallArguments args(e);
1329 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1330 vmSymbols::throwable_void_signature(),
1331 &args);
1332 }
1333 }
1334 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1335 }
1336
1337
1338 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1339 Handle h_init_lock(THREAD, init_lock());
1340 if (h_init_lock() != nullptr) {
1341 ObjectLocker ol(h_init_lock, THREAD);
1342 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1343 set_init_state(state);
1344 fence_and_clear_init_lock();
1345 ol.notify_all(CHECK);
1346 } else {
1347 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1348 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1349 set_init_state(state);
1350 }
1351 }
1352
1353 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1354 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1355 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1356 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1357
1358 DeoptimizationScope deopt_scope;
1359 {
1360 MutexLocker ml(current, Compile_lock);
1361
1362 set_init_state(InstanceKlass::loaded);
1363 // make sure init_state store is already done.
1364 // The compiler reads the hierarchy outside of the Compile_lock.
1365 // Access ordering is used to add to hierarchy.
1366
1367 // Link into hierarchy.
1368 append_to_sibling_list(); // add to superklass/sibling list
1369 process_interfaces(); // handle all "implements" declarations
1370
1371 // Now mark all code that depended on old class hierarchy.
1372 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1373 if (Universe::is_fully_initialized()) {
1374 CodeCache::mark_dependents_on(&deopt_scope, this);
1375 }
1376 }
1377 // Perform the deopt handshake outside Compile_lock.
1378 deopt_scope.deoptimize_marked();
1379 }
1380
1381
1382 InstanceKlass* InstanceKlass::implementor() const {
1383 InstanceKlass* volatile* ik = adr_implementor();
1384 if (ik == nullptr) {
1385 return nullptr;
1386 } else {
1387 // This load races with inserts, and therefore needs acquire.
1388 InstanceKlass* ikls = Atomic::load_acquire(ik);
1389 if (ikls != nullptr && !ikls->is_loader_alive()) {
1390 return nullptr; // don't return unloaded class
1391 } else {
1392 return ikls;
1393 }
1394 }
1395 }
1396
1397
1398 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1399 assert_locked_or_safepoint(Compile_lock);
1400 assert(is_interface(), "not interface");
1401 InstanceKlass* volatile* addr = adr_implementor();
1402 assert(addr != nullptr, "null addr");
1403 if (addr != nullptr) {
1404 Atomic::release_store(addr, ik);
1405 }
1406 }
1407
1408 int InstanceKlass::nof_implementors() const {
1409 InstanceKlass* ik = implementor();
1410 if (ik == nullptr) {
1411 return 0;
1412 } else if (ik != this) {
1413 return 1;
1414 } else {
1415 return 2;
1416 }
1417 }
1418
1419 // The embedded _implementor field can only record one implementor.
1420 // When there are more than one implementors, the _implementor field
1421 // is set to the interface Klass* itself. Following are the possible
1422 // values for the _implementor field:
1423 // null - no implementor
1424 // implementor Klass* - one implementor
1425 // self - more than one implementor
1426 //
1427 // The _implementor field only exists for interfaces.
1428 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1429 if (Universe::is_fully_initialized()) {
1430 assert_lock_strong(Compile_lock);
1431 }
1432 assert(is_interface(), "not interface");
1433 // Filter out my subinterfaces.
1434 // (Note: Interfaces are never on the subklass list.)
1435 if (ik->is_interface()) return;
1436
1437 // Filter out subclasses whose supers already implement me.
1438 // (Note: CHA must walk subclasses of direct implementors
1439 // in order to locate indirect implementors.)
1440 InstanceKlass* super_ik = ik->java_super();
1441 if (super_ik != nullptr && super_ik->implements_interface(this))
1442 // We only need to check one immediate superclass, since the
1443 // implements_interface query looks at transitive_interfaces.
1444 // Any supers of the super have the same (or fewer) transitive_interfaces.
1445 return;
1446
1447 InstanceKlass* iklass = implementor();
1448 if (iklass == nullptr) {
1449 set_implementor(ik);
1450 } else if (iklass != this && iklass != ik) {
1451 // There is already an implementor. Use itself as an indicator of
1452 // more than one implementors.
1453 set_implementor(this);
1454 }
1455
1456 // The implementor also implements the transitive_interfaces
1457 for (int index = 0; index < local_interfaces()->length(); index++) {
1458 local_interfaces()->at(index)->add_implementor(ik);
1459 }
1460 }
1461
1462 void InstanceKlass::init_implementor() {
1463 if (is_interface()) {
1464 set_implementor(nullptr);
1465 }
1466 }
1467
1468
1469 void InstanceKlass::process_interfaces() {
1470 // link this class into the implementors list of every interface it implements
1471 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1472 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1473 InstanceKlass* interf = local_interfaces()->at(i);
1474 assert(interf->is_interface(), "expected interface");
1475 interf->add_implementor(this);
1476 }
1477 }
1478
1479 bool InstanceKlass::can_be_primary_super_slow() const {
1480 if (is_interface())
1481 return false;
1482 else
1483 return Klass::can_be_primary_super_slow();
1484 }
1485
1486 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1487 Array<InstanceKlass*>* transitive_interfaces) {
1488 // The secondaries are the implemented interfaces.
1489 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1490 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1491 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1492 int num_secondaries = num_extra_slots + interfaces->length();
1493 if (num_secondaries == 0) {
1494 // Must share this for correct bootstrapping!
1495 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1496 return nullptr;
1497 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1498 // We will reuse the transitive interfaces list if we're certain
1499 // it's in hash order.
1500 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1501 set_secondary_supers(interfaces, bitmap);
1502 return nullptr;
1503 }
1504 // Copy transitive interfaces to a temporary growable array to be constructed
1505 // into the secondary super list with extra slots.
1506 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1507 for (int i = 0; i < interfaces->length(); i++) {
1508 secondaries->push(interfaces->at(i));
1509 }
1510 return secondaries;
1511 }
1512
1513 bool InstanceKlass::implements_interface(Klass* k) const {
1514 if (this == k) return true;
1515 assert(k->is_interface(), "should be an interface class");
1516 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1517 if (transitive_interfaces()->at(i) == k) {
1518 return true;
1519 }
1520 }
1521 return false;
1522 }
1523
1524 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1525 // Verify direct super interface
1526 if (this == k) return true;
1527 assert(k->is_interface(), "should be an interface class");
1528 for (int i = 0; i < local_interfaces()->length(); i++) {
1529 if (local_interfaces()->at(i) == k) {
1530 return true;
1531 }
1532 }
1533 return false;
1534 }
1535
1536 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1537 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1538 size_t size = objArrayOopDesc::object_size(length);
1539 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1540 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1541 /* do_zero */ true, CHECK_NULL);
1542 return o;
1543 }
1544
1545 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1546 if (TraceFinalizerRegistration) {
1547 tty->print("Registered ");
1548 i->print_value_on(tty);
1549 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1550 }
1551 instanceHandle h_i(THREAD, i);
1552 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1553 JavaValue result(T_VOID);
1554 JavaCallArguments args(h_i);
1555 methodHandle mh(THREAD, Universe::finalizer_register_method());
1556 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1557 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1558 return h_i();
1559 }
1560
1561 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1562 assert(!is_abstract() && !is_interface(), "Should not create this object");
1563 size_t size = size_helper(); // Query before forming handle.
1564 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1565 }
1566
1567 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1568 Klass* k = java_lang_Class::as_Klass(java_class);
1569 if (k == nullptr) {
1570 ResourceMark rm(THREAD);
1571 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1572 }
1573 InstanceKlass* ik = cast(k);
1574 ik->check_valid_for_instantiation(false, CHECK_NULL);
1575 ik->initialize(CHECK_NULL);
1576 return ik->allocate_instance(THREAD);
1577 }
1578
1579 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1580 return instanceHandle(THREAD, allocate_instance(THREAD));
1581 }
1582
1583 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1584 if (is_interface() || is_abstract()) {
1585 ResourceMark rm(THREAD);
1586 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1587 : vmSymbols::java_lang_InstantiationException(), external_name());
1588 }
1589 if (this == vmClasses::Class_klass()) {
1590 ResourceMark rm(THREAD);
1591 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1592 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1593 }
1594 }
1595
1596 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1597 // Need load-acquire for lock-free read
1598 if (array_klasses_acquire() == nullptr) {
1599
1600 // Recursively lock array allocation
1601 RecursiveLocker rl(MultiArray_lock, THREAD);
1602
1603 // Check if another thread created the array klass while we were waiting for the lock.
1604 if (array_klasses() == nullptr) {
1605 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1606 // use 'release' to pair with lock-free load
1607 release_set_array_klasses(k);
1608 }
1609 }
1610
1611 // array_klasses() will always be set at this point
1612 ObjArrayKlass* ak = array_klasses();
1613 assert(ak != nullptr, "should be set");
1614 return ak->array_klass(n, THREAD);
1615 }
1616
1617 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1618 // Need load-acquire for lock-free read
1619 ObjArrayKlass* oak = array_klasses_acquire();
1620 if (oak == nullptr) {
1621 return nullptr;
1622 } else {
1623 return oak->array_klass_or_null(n);
1624 }
1625 }
1626
1627 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1628 return array_klass(1, THREAD);
1629 }
1630
1631 ArrayKlass* InstanceKlass::array_klass_or_null() {
1632 return array_klass_or_null(1);
1633 }
1634
1635 static int call_class_initializer_counter = 0; // for debugging
1636
1637 Method* InstanceKlass::class_initializer() const {
1638 Method* clinit = find_method(
1639 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1640 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1641 return clinit;
1642 }
1643 return nullptr;
1644 }
1645
1646 void InstanceKlass::call_class_initializer(TRAPS) {
1647 if (ReplayCompiles &&
1648 (ReplaySuppressInitializers == 1 ||
1649 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1650 // Hide the existence of the initializer for the purpose of replaying the compile
1651 return;
1652 }
1653
1654 #if INCLUDE_CDS
1655 // This is needed to ensure the consistency of the archived heap objects.
1656 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1657 AOTClassInitializer::call_runtime_setup(THREAD, this);
1658 return;
1659 } else if (has_archived_enum_objs()) {
1660 assert(is_shared(), "must be");
1661 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1662 if (initialized) {
1663 return;
1664 }
1665 }
1666 #endif
1667
1668 methodHandle h_method(THREAD, class_initializer());
1669 assert(!is_initialized(), "we cannot initialize twice");
1670 LogTarget(Info, class, init) lt;
1671 if (lt.is_enabled()) {
1672 ResourceMark rm(THREAD);
1673 LogStream ls(lt);
1674 ls.print("%d Initializing ", call_class_initializer_counter++);
1675 name()->print_value_on(&ls);
1676 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1677 h_method() == nullptr ? "(no method)" : "", p2i(this),
1678 THREAD->name());
1679 }
1680 if (h_method() != nullptr) {
1681 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1682 JavaCallArguments args; // No arguments
1683 JavaValue result(T_VOID);
1684 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1685 }
1686 }
1687
1688 // If a class that implements this interface is initialized, is the JVM required
1689 // to first execute a <clinit> method declared in this interface,
1690 // or (if also_check_supers==true) any of the super types of this interface?
1691 //
1692 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1693 // an interface, then let SC be its superclass and let SI1, ..., SIn
1694 // be all superinterfaces of C (whether direct or indirect) that
1695 // declare at least one non-abstract, non-static method.
1696 //
1697 // So when an interface is initialized, it does not look at its
1698 // supers. But a proper class will ensure that all of its supers have
1699 // run their <clinit> methods, except that it disregards interfaces
1700 // that lack a non-static concrete method (i.e., a default method).
1701 // Therefore, you should probably call this method only when the
1702 // current class is a super of some proper class, not an interface.
1703 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1704 assert(is_interface(), "must be");
1705
1706 if (!has_nonstatic_concrete_methods()) {
1707 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1708 return false;
1709 }
1710
1711 // JVMS 5.5. Initialization
1712 // ...If C is an interface that declares a non-abstract,
1713 // non-static method, the initialization of a class that
1714 // implements C directly or indirectly.
1715 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1716 return true;
1717 }
1718 if (also_check_supers) {
1719 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1720 for (int i = 0; i < all_ifs->length(); ++i) {
1721 InstanceKlass* super_intf = all_ifs->at(i);
1722 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1723 return true;
1724 }
1725 }
1726 }
1727 return false;
1728 }
1729
1730 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1731 InterpreterOopMap* entry_for) {
1732 // Lazily create the _oop_map_cache at first request.
1733 // Load_acquire is needed to safely get instance published with CAS by another thread.
1734 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1735 if (oop_map_cache == nullptr) {
1736 // Try to install new instance atomically.
1737 oop_map_cache = new OopMapCache();
1738 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1739 if (other != nullptr) {
1740 // Someone else managed to install before us, ditch local copy and use the existing one.
1741 delete oop_map_cache;
1742 oop_map_cache = other;
1743 }
1744 }
1745 // _oop_map_cache is constant after init; lookup below does its own locking.
1746 oop_map_cache->lookup(method, bci, entry_for);
1747 }
1748
1749 bool InstanceKlass::contains_field_offset(int offset) {
1750 fieldDescriptor fd;
1751 return find_field_from_offset(offset, false, &fd);
1752 }
1753
1754 FieldInfo InstanceKlass::field(int index) const {
1755 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1756 if (fs.index() == index) {
1757 return fs.to_FieldInfo();
1758 }
1759 }
1760 fatal("Field not found");
1761 return FieldInfo();
1762 }
1763
1764 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1765 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1766 Symbol* f_name = fs.name();
1767 Symbol* f_sig = fs.signature();
1768 if (f_name == name && f_sig == sig) {
1769 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1770 return true;
1771 }
1772 }
1773 return false;
1774 }
1775
1776
1777 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1778 const int n = local_interfaces()->length();
1779 for (int i = 0; i < n; i++) {
1780 Klass* intf1 = local_interfaces()->at(i);
1781 assert(intf1->is_interface(), "just checking type");
1782 // search for field in current interface
1783 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1784 assert(fd->is_static(), "interface field must be static");
1785 return intf1;
1786 }
1787 // search for field in direct superinterfaces
1788 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1789 if (intf2 != nullptr) return intf2;
1790 }
1791 // otherwise field lookup fails
1792 return nullptr;
1793 }
1794
1795
1796 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1797 // search order according to newest JVM spec (5.4.3.2, p.167).
1798 // 1) search for field in current klass
1799 if (find_local_field(name, sig, fd)) {
1800 return const_cast<InstanceKlass*>(this);
1801 }
1802 // 2) search for field recursively in direct superinterfaces
1803 { Klass* intf = find_interface_field(name, sig, fd);
1804 if (intf != nullptr) return intf;
1805 }
1806 // 3) apply field lookup recursively if superclass exists
1807 { Klass* supr = super();
1808 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1809 }
1810 // 4) otherwise field lookup fails
1811 return nullptr;
1812 }
1813
1814
1815 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1816 // search order according to newest JVM spec (5.4.3.2, p.167).
1817 // 1) search for field in current klass
1818 if (find_local_field(name, sig, fd)) {
1819 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1820 }
1821 // 2) search for field recursively in direct superinterfaces
1822 if (is_static) {
1823 Klass* intf = find_interface_field(name, sig, fd);
1824 if (intf != nullptr) return intf;
1825 }
1826 // 3) apply field lookup recursively if superclass exists
1827 { Klass* supr = super();
1828 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1829 }
1830 // 4) otherwise field lookup fails
1831 return nullptr;
1832 }
1833
1834
1835 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1836 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1837 if (fs.offset() == offset) {
1838 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1839 if (fd->is_static() == is_static) return true;
1840 }
1841 }
1842 return false;
1843 }
1844
1845
1846 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1847 Klass* klass = const_cast<InstanceKlass*>(this);
1848 while (klass != nullptr) {
1849 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1850 return true;
1851 }
1852 klass = klass->super();
1853 }
1854 return false;
1855 }
1856
1857
1858 void InstanceKlass::methods_do(void f(Method* method)) {
1859 // Methods aren't stable until they are loaded. This can be read outside
1860 // a lock through the ClassLoaderData for profiling
1861 // Redefined scratch classes are on the list and need to be cleaned
1862 if (!is_loaded() && !is_scratch_class()) {
1863 return;
1864 }
1865
1866 int len = methods()->length();
1867 for (int index = 0; index < len; index++) {
1868 Method* m = methods()->at(index);
1869 assert(m->is_method(), "must be method");
1870 f(m);
1871 }
1872 }
1873
1874
1875 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1876 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1877 if (fs.access_flags().is_static()) {
1878 fieldDescriptor& fd = fs.field_descriptor();
1879 cl->do_field(&fd);
1880 }
1881 }
1882 }
1883
1884
1885 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1886 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1887 if (fs.access_flags().is_static()) {
1888 fieldDescriptor& fd = fs.field_descriptor();
1889 f(&fd, mirror, CHECK);
1890 }
1891 }
1892 }
1893
1894 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1895 InstanceKlass* super = superklass();
1896 if (super != nullptr) {
1897 super->do_nonstatic_fields(cl);
1898 }
1899 fieldDescriptor fd;
1900 int length = java_fields_count();
1901 for (int i = 0; i < length; i += 1) {
1902 fd.reinitialize(this, i);
1903 if (!fd.is_static()) {
1904 cl->do_field(&fd);
1905 }
1906 }
1907 }
1908
1909 // first in Pair is offset, second is index.
1910 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1911 return a->first - b->first;
1912 }
1913
1914 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1915 InstanceKlass* super = superklass();
1916 if (super != nullptr) {
1917 super->print_nonstatic_fields(cl);
1918 }
1919 ResourceMark rm;
1920 fieldDescriptor fd;
1921 // In DebugInfo nonstatic fields are sorted by offset.
1922 GrowableArray<Pair<int,int> > fields_sorted;
1923 int i = 0;
1924 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1925 if (!fs.access_flags().is_static()) {
1926 fd = fs.field_descriptor();
1927 Pair<int,int> f(fs.offset(), fs.index());
1928 fields_sorted.push(f);
1929 i++;
1930 }
1931 }
1932 if (i > 0) {
1933 int length = i;
1934 assert(length == fields_sorted.length(), "duh");
1935 fields_sorted.sort(compare_fields_by_offset);
1936 for (int i = 0; i < length; i++) {
1937 fd.reinitialize(this, fields_sorted.at(i).second);
1938 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1939 cl->do_field(&fd);
1940 }
1941 }
1942 }
1943
1944 #ifdef ASSERT
1945 static int linear_search(const Array<Method*>* methods,
1946 const Symbol* name,
1947 const Symbol* signature) {
1948 const int len = methods->length();
1949 for (int index = 0; index < len; index++) {
1950 const Method* const m = methods->at(index);
1951 assert(m->is_method(), "must be method");
1952 if (m->signature() == signature && m->name() == name) {
1953 return index;
1954 }
1955 }
1956 return -1;
1957 }
1958 #endif
1959
1960 bool InstanceKlass::_disable_method_binary_search = false;
1961
1962 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1963 int len = methods->length();
1964 int l = 0;
1965 int h = len - 1;
1966 while (l <= h) {
1967 Method* m = methods->at(l);
1968 if (m->name() == name) {
1969 return l;
1970 }
1971 l++;
1972 }
1973 return -1;
1974 }
1975
1976 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1977 if (_disable_method_binary_search) {
1978 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
1979 // At the final stage of dynamic dumping, the methods array may not be sorted
1980 // by ascending addresses of their names, so we can't use binary search anymore.
1981 // However, methods with the same name are still laid out consecutively inside the
1982 // methods array, so let's look for the first one that matches.
1983 return linear_search(methods, name);
1984 }
1985
1986 int len = methods->length();
1987 int l = 0;
1988 int h = len - 1;
1989
1990 // methods are sorted by ascending addresses of their names, so do binary search
1991 while (l <= h) {
1992 int mid = (l + h) >> 1;
1993 Method* m = methods->at(mid);
1994 assert(m->is_method(), "must be method");
1995 int res = m->name()->fast_compare(name);
1996 if (res == 0) {
1997 return mid;
1998 } else if (res < 0) {
1999 l = mid + 1;
2000 } else {
2001 h = mid - 1;
2002 }
2003 }
2004 return -1;
2005 }
2006
2007 // find_method looks up the name/signature in the local methods array
2008 Method* InstanceKlass::find_method(const Symbol* name,
2009 const Symbol* signature) const {
2010 return find_method_impl(name, signature,
2011 OverpassLookupMode::find,
2012 StaticLookupMode::find,
2013 PrivateLookupMode::find);
2014 }
2015
2016 Method* InstanceKlass::find_method_impl(const Symbol* name,
2017 const Symbol* signature,
2018 OverpassLookupMode overpass_mode,
2019 StaticLookupMode static_mode,
2020 PrivateLookupMode private_mode) const {
2021 return InstanceKlass::find_method_impl(methods(),
2022 name,
2023 signature,
2024 overpass_mode,
2025 static_mode,
2026 private_mode);
2027 }
2028
2029 // find_instance_method looks up the name/signature in the local methods array
2030 // and skips over static methods
2031 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2032 const Symbol* name,
2033 const Symbol* signature,
2034 PrivateLookupMode private_mode) {
2035 Method* const meth = InstanceKlass::find_method_impl(methods,
2036 name,
2037 signature,
2038 OverpassLookupMode::find,
2039 StaticLookupMode::skip,
2040 private_mode);
2041 assert(((meth == nullptr) || !meth->is_static()),
2042 "find_instance_method should have skipped statics");
2043 return meth;
2044 }
2045
2046 // find_instance_method looks up the name/signature in the local methods array
2047 // and skips over static methods
2048 Method* InstanceKlass::find_instance_method(const Symbol* name,
2049 const Symbol* signature,
2050 PrivateLookupMode private_mode) const {
2051 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2052 }
2053
2054 // Find looks up the name/signature in the local methods array
2055 // and filters on the overpass, static and private flags
2056 // This returns the first one found
2057 // note that the local methods array can have up to one overpass, one static
2058 // and one instance (private or not) with the same name/signature
2059 Method* InstanceKlass::find_local_method(const Symbol* name,
2060 const Symbol* signature,
2061 OverpassLookupMode overpass_mode,
2062 StaticLookupMode static_mode,
2063 PrivateLookupMode private_mode) const {
2064 return InstanceKlass::find_method_impl(methods(),
2065 name,
2066 signature,
2067 overpass_mode,
2068 static_mode,
2069 private_mode);
2070 }
2071
2072 // Find looks up the name/signature in the local methods array
2073 // and filters on the overpass, static and private flags
2074 // This returns the first one found
2075 // note that the local methods array can have up to one overpass, one static
2076 // and one instance (private or not) with the same name/signature
2077 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2078 const Symbol* name,
2079 const Symbol* signature,
2080 OverpassLookupMode overpass_mode,
2081 StaticLookupMode static_mode,
2082 PrivateLookupMode private_mode) {
2083 return InstanceKlass::find_method_impl(methods,
2084 name,
2085 signature,
2086 overpass_mode,
2087 static_mode,
2088 private_mode);
2089 }
2090
2091 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2092 const Symbol* name,
2093 const Symbol* signature) {
2094 return InstanceKlass::find_method_impl(methods,
2095 name,
2096 signature,
2097 OverpassLookupMode::find,
2098 StaticLookupMode::find,
2099 PrivateLookupMode::find);
2100 }
2101
2102 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2103 const Symbol* name,
2104 const Symbol* signature,
2105 OverpassLookupMode overpass_mode,
2106 StaticLookupMode static_mode,
2107 PrivateLookupMode private_mode) {
2108 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2109 return hit >= 0 ? methods->at(hit): nullptr;
2110 }
2111
2112 // true if method matches signature and conforms to skipping_X conditions.
2113 static bool method_matches(const Method* m,
2114 const Symbol* signature,
2115 bool skipping_overpass,
2116 bool skipping_static,
2117 bool skipping_private) {
2118 return ((m->signature() == signature) &&
2119 (!skipping_overpass || !m->is_overpass()) &&
2120 (!skipping_static || !m->is_static()) &&
2121 (!skipping_private || !m->is_private()));
2122 }
2123
2124 // Used directly for default_methods to find the index into the
2125 // default_vtable_indices, and indirectly by find_method
2126 // find_method_index looks in the local methods array to return the index
2127 // of the matching name/signature. If, overpass methods are being ignored,
2128 // the search continues to find a potential non-overpass match. This capability
2129 // is important during method resolution to prefer a static method, for example,
2130 // over an overpass method.
2131 // There is the possibility in any _method's array to have the same name/signature
2132 // for a static method, an overpass method and a local instance method
2133 // To correctly catch a given method, the search criteria may need
2134 // to explicitly skip the other two. For local instance methods, it
2135 // is often necessary to skip private methods
2136 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2137 const Symbol* name,
2138 const Symbol* signature,
2139 OverpassLookupMode overpass_mode,
2140 StaticLookupMode static_mode,
2141 PrivateLookupMode private_mode) {
2142 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2143 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2144 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2145 const int hit = quick_search(methods, name);
2146 if (hit != -1) {
2147 const Method* const m = methods->at(hit);
2148
2149 // Do linear search to find matching signature. First, quick check
2150 // for common case, ignoring overpasses if requested.
2151 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2152 return hit;
2153 }
2154
2155 // search downwards through overloaded methods
2156 int i;
2157 for (i = hit - 1; i >= 0; --i) {
2158 const Method* const m = methods->at(i);
2159 assert(m->is_method(), "must be method");
2160 if (m->name() != name) {
2161 break;
2162 }
2163 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2164 return i;
2165 }
2166 }
2167 // search upwards
2168 for (i = hit + 1; i < methods->length(); ++i) {
2169 const Method* const m = methods->at(i);
2170 assert(m->is_method(), "must be method");
2171 if (m->name() != name) {
2172 break;
2173 }
2174 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2175 return i;
2176 }
2177 }
2178 // not found
2179 #ifdef ASSERT
2180 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2181 linear_search(methods, name, signature);
2182 assert(-1 == index, "binary search should have found entry %d", index);
2183 #endif
2184 }
2185 return -1;
2186 }
2187
2188 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2189 return find_method_by_name(methods(), name, end);
2190 }
2191
2192 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2193 const Symbol* name,
2194 int* end_ptr) {
2195 assert(end_ptr != nullptr, "just checking");
2196 int start = quick_search(methods, name);
2197 int end = start + 1;
2198 if (start != -1) {
2199 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2200 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2201 *end_ptr = end;
2202 return start;
2203 }
2204 return -1;
2205 }
2206
2207 // uncached_lookup_method searches both the local class methods array and all
2208 // superclasses methods arrays, skipping any overpass methods in superclasses,
2209 // and possibly skipping private methods.
2210 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2211 const Symbol* signature,
2212 OverpassLookupMode overpass_mode,
2213 PrivateLookupMode private_mode) const {
2214 OverpassLookupMode overpass_local_mode = overpass_mode;
2215 const Klass* klass = this;
2216 while (klass != nullptr) {
2217 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2218 signature,
2219 overpass_local_mode,
2220 StaticLookupMode::find,
2221 private_mode);
2222 if (method != nullptr) {
2223 return method;
2224 }
2225 klass = klass->super();
2226 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2227 }
2228 return nullptr;
2229 }
2230
2231 #ifdef ASSERT
2232 // search through class hierarchy and return true if this class or
2233 // one of the superclasses was redefined
2234 bool InstanceKlass::has_redefined_this_or_super() const {
2235 const Klass* klass = this;
2236 while (klass != nullptr) {
2237 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2238 return true;
2239 }
2240 klass = klass->super();
2241 }
2242 return false;
2243 }
2244 #endif
2245
2246 // lookup a method in the default methods list then in all transitive interfaces
2247 // Do NOT return private or static methods
2248 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2249 Symbol* signature) const {
2250 Method* m = nullptr;
2251 if (default_methods() != nullptr) {
2252 m = find_method(default_methods(), name, signature);
2253 }
2254 // Look up interfaces
2255 if (m == nullptr) {
2256 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2257 }
2258 return m;
2259 }
2260
2261 // lookup a method in all the interfaces that this class implements
2262 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2263 // They should only be found in the initial InterfaceMethodRef
2264 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2265 Symbol* signature,
2266 DefaultsLookupMode defaults_mode) const {
2267 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2268 int num_ifs = all_ifs->length();
2269 InstanceKlass *ik = nullptr;
2270 for (int i = 0; i < num_ifs; i++) {
2271 ik = all_ifs->at(i);
2272 Method* m = ik->lookup_method(name, signature);
2273 if (m != nullptr && m->is_public() && !m->is_static() &&
2274 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2275 return m;
2276 }
2277 }
2278 return nullptr;
2279 }
2280
2281 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2282 :_st(st), _verbose(verbose) {
2283 ResourceMark rm;
2284 _st->print("%-18s ", "KlassAddr");
2285 _st->print("%-4s ", "Size");
2286 _st->print("%-20s ", "State");
2287 _st->print("%-7s ", "Flags");
2288 _st->print("%-5s ", "ClassName");
2289 _st->cr();
2290 }
2291
2292 void PrintClassClosure::do_klass(Klass* k) {
2293 ResourceMark rm;
2294 // klass pointer
2295 _st->print(PTR_FORMAT " ", p2i(k));
2296 // klass size
2297 _st->print("%4d ", k->size());
2298 // initialization state
2299 if (k->is_instance_klass()) {
2300 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2301 } else {
2302 _st->print("%-20s ","");
2303 }
2304 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2305 char buf[10];
2306 int i = 0;
2307 if (k->has_finalizer()) buf[i++] = 'F';
2308 if (k->is_instance_klass()) {
2309 InstanceKlass* ik = InstanceKlass::cast(k);
2310 if (ik->has_final_method()) buf[i++] = 'f';
2311 if (ik->is_rewritten()) buf[i++] = 'W';
2312 if (ik->is_contended()) buf[i++] = 'C';
2313 if (ik->has_been_redefined()) buf[i++] = 'R';
2314 if (ik->is_shared()) buf[i++] = 'S';
2315 }
2316 buf[i++] = '\0';
2317 _st->print("%-7s ", buf);
2318 // klass name
2319 _st->print("%-5s ", k->external_name());
2320 // end
2321 _st->cr();
2322 if (_verbose) {
2323 k->print_on(_st);
2324 }
2325 }
2326
2327 /* jni_id_for for jfieldIds only */
2328 JNIid* InstanceKlass::jni_id_for(int offset) {
2329 MutexLocker ml(JfieldIdCreation_lock);
2330 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2331 if (probe == nullptr) {
2332 // Allocate new static field identifier
2333 probe = new JNIid(this, offset, jni_ids());
2334 set_jni_ids(probe);
2335 }
2336 return probe;
2337 }
2338
2339 u2 InstanceKlass::enclosing_method_data(int offset) const {
2340 const Array<jushort>* const inner_class_list = inner_classes();
2341 if (inner_class_list == nullptr) {
2342 return 0;
2343 }
2344 const int length = inner_class_list->length();
2345 if (length % inner_class_next_offset == 0) {
2346 return 0;
2347 }
2348 const int index = length - enclosing_method_attribute_size;
2349 assert(offset < enclosing_method_attribute_size, "invalid offset");
2350 return inner_class_list->at(index + offset);
2351 }
2352
2353 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2354 u2 method_index) {
2355 Array<jushort>* inner_class_list = inner_classes();
2356 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2357 int length = inner_class_list->length();
2358 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2359 int index = length - enclosing_method_attribute_size;
2360 inner_class_list->at_put(
2361 index + enclosing_method_class_index_offset, class_index);
2362 inner_class_list->at_put(
2363 index + enclosing_method_method_index_offset, method_index);
2364 }
2365 }
2366
2367 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2368 if (method->is_old() && !method->is_obsolete()) {
2369 // If the method passed in is old (but not obsolete), use the current version.
2370 method = method_with_idnum((int)idnum);
2371 assert(method != nullptr, "old and but not obsolete, so should exist");
2372 }
2373 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2374 Atomic::release_store(&jmeths[idnum + 1], new_id);
2375 return new_id;
2376 }
2377
2378 // Lookup or create a jmethodID.
2379 // This code is called by the VMThread and JavaThreads so the
2380 // locking has to be done very carefully to avoid deadlocks
2381 // and/or other cache consistency problems.
2382 //
2383 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2384 Method* method = method_h();
2385 int idnum = method->method_idnum();
2386 jmethodID* jmeths = methods_jmethod_ids_acquire();
2387
2388 // We use a double-check locking idiom here because this cache is
2389 // performance sensitive. In the normal system, this cache only
2390 // transitions from null to non-null which is safe because we use
2391 // release_set_methods_jmethod_ids() to advertise the new cache.
2392 // A partially constructed cache should never be seen by a racing
2393 // thread. We also use release_store() to save a new jmethodID
2394 // in the cache so a partially constructed jmethodID should never be
2395 // seen either. Cache reads of existing jmethodIDs proceed without a
2396 // lock, but cache writes of a new jmethodID requires uniqueness and
2397 // creation of the cache itself requires no leaks so a lock is
2398 // acquired in those two cases.
2399 //
2400 // If the RedefineClasses() API has been used, then this cache grows
2401 // in the redefinition safepoint.
2402
2403 if (jmeths == nullptr) {
2404 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2405 jmeths = methods_jmethod_ids_acquire();
2406 // Still null?
2407 if (jmeths == nullptr) {
2408 size_t size = idnum_allocated_count();
2409 assert(size > (size_t)idnum, "should already have space");
2410 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2411 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2412 // cache size is stored in element[0], other elements offset by one
2413 jmeths[0] = (jmethodID)size;
2414 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2415
2416 // publish jmeths
2417 release_set_methods_jmethod_ids(jmeths);
2418 return new_id;
2419 }
2420 }
2421
2422 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2423 if (id == nullptr) {
2424 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2425 id = jmeths[idnum + 1];
2426 // Still null?
2427 if (id == nullptr) {
2428 return update_jmethod_id(jmeths, method, idnum);
2429 }
2430 }
2431 return id;
2432 }
2433
2434 void InstanceKlass::update_methods_jmethod_cache() {
2435 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2436 jmethodID* cache = _methods_jmethod_ids;
2437 if (cache != nullptr) {
2438 size_t size = idnum_allocated_count();
2439 size_t old_size = (size_t)cache[0];
2440 if (old_size < size + 1) {
2441 // Allocate a larger one and copy entries to the new one.
2442 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2443 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2444 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2445 // The cache size is stored in element[0]; the other elements are offset by one.
2446 new_cache[0] = (jmethodID)size;
2447
2448 for (int i = 1; i <= (int)old_size; i++) {
2449 new_cache[i] = cache[i];
2450 }
2451 _methods_jmethod_ids = new_cache;
2452 FREE_C_HEAP_ARRAY(jmethodID, cache);
2453 }
2454 }
2455 }
2456
2457 // Figure out how many jmethodIDs haven't been allocated, and make
2458 // sure space for them is pre-allocated. This makes getting all
2459 // method ids much, much faster with classes with more than 8
2460 // methods, and has a *substantial* effect on performance with jvmti
2461 // code that loads all jmethodIDs for all classes.
2462 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2463 int new_jmeths = 0;
2464 int length = methods()->length();
2465 for (int index = start_offset; index < length; index++) {
2466 Method* m = methods()->at(index);
2467 jmethodID id = m->find_jmethod_id_or_null();
2468 if (id == nullptr) {
2469 new_jmeths++;
2470 }
2471 }
2472 if (new_jmeths != 0) {
2473 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2474 }
2475 }
2476
2477 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2478 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2479 int idnum = method->method_idnum();
2480 jmethodID* jmeths = methods_jmethod_ids_acquire();
2481 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2482 }
2483
2484 inline DependencyContext InstanceKlass::dependencies() {
2485 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2486 return dep_context;
2487 }
2488
2489 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2490 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2491 }
2492
2493 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2494 dependencies().add_dependent_nmethod(nm);
2495 }
2496
2497 void InstanceKlass::clean_dependency_context() {
2498 dependencies().clean_unloading_dependents();
2499 }
2500
2501 #ifndef PRODUCT
2502 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2503 dependencies().print_dependent_nmethods(verbose);
2504 }
2505
2506 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2507 return dependencies().is_dependent_nmethod(nm);
2508 }
2509 #endif //PRODUCT
2510
2511 void InstanceKlass::clean_weak_instanceklass_links() {
2512 clean_implementors_list();
2513 clean_method_data();
2514 }
2515
2516 void InstanceKlass::clean_implementors_list() {
2517 assert(is_loader_alive(), "this klass should be live");
2518 if (is_interface()) {
2519 assert (ClassUnloading, "only called for ClassUnloading");
2520 for (;;) {
2521 // Use load_acquire due to competing with inserts
2522 InstanceKlass* volatile* iklass = adr_implementor();
2523 assert(iklass != nullptr, "Klass must not be null");
2524 InstanceKlass* impl = Atomic::load_acquire(iklass);
2525 if (impl != nullptr && !impl->is_loader_alive()) {
2526 // null this field, might be an unloaded instance klass or null
2527 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2528 // Successfully unlinking implementor.
2529 if (log_is_enabled(Trace, class, unload)) {
2530 ResourceMark rm;
2531 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2532 }
2533 return;
2534 }
2535 } else {
2536 return;
2537 }
2538 }
2539 }
2540 }
2541
2542 void InstanceKlass::clean_method_data() {
2543 for (int m = 0; m < methods()->length(); m++) {
2544 MethodData* mdo = methods()->at(m)->method_data();
2545 if (mdo != nullptr) {
2546 mdo->clean_method_data(/*always_clean*/false);
2547 }
2548 }
2549 }
2550
2551 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2552 Klass::metaspace_pointers_do(it);
2553
2554 if (log_is_enabled(Trace, cds)) {
2555 ResourceMark rm;
2556 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2557 }
2558
2559 it->push(&_annotations);
2560 it->push((Klass**)&_array_klasses);
2561 if (!is_rewritten()) {
2562 it->push(&_constants, MetaspaceClosure::_writable);
2563 } else {
2564 it->push(&_constants);
2565 }
2566 it->push(&_inner_classes);
2567 #if INCLUDE_JVMTI
2568 it->push(&_previous_versions);
2569 #endif
2570 #if INCLUDE_CDS
2571 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2572 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2573 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2574 // The length check on the _methods is necessary because classes which don't have any
2575 // methods share the Universe::_the_empty_method_array which is in the RO region.
2576 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2577 // To handle jsr bytecode, new Method* maybe stored into _methods
2578 it->push(&_methods, MetaspaceClosure::_writable);
2579 } else {
2580 #endif
2581 it->push(&_methods);
2582 #if INCLUDE_CDS
2583 }
2584 #endif
2585 it->push(&_default_methods);
2586 it->push(&_local_interfaces);
2587 it->push(&_transitive_interfaces);
2588 it->push(&_method_ordering);
2589 if (!is_rewritten()) {
2590 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2591 } else {
2592 it->push(&_default_vtable_indices);
2593 }
2594
2595 it->push(&_fieldinfo_stream);
2596 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2597 it->push(&_fields_status, MetaspaceClosure::_writable);
2598
2599 if (itable_length() > 0) {
2600 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2601 int method_table_offset_in_words = ioe->offset()/wordSize;
2602 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2603
2604 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2605 / itableOffsetEntry::size();
2606
2607 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2608 if (ioe->interface_klass() != nullptr) {
2609 it->push(ioe->interface_klass_addr());
2610 itableMethodEntry* ime = ioe->first_method_entry(this);
2611 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2612 for (int index = 0; index < n; index ++) {
2613 it->push(ime[index].method_addr());
2614 }
2615 }
2616 }
2617 }
2618
2619 it->push(&_nest_host);
2620 it->push(&_nest_members);
2621 it->push(&_permitted_subclasses);
2622 it->push(&_record_components);
2623 }
2624
2625 #if INCLUDE_CDS
2626 void InstanceKlass::remove_unshareable_info() {
2627
2628 if (is_linked()) {
2629 assert(can_be_verified_at_dumptime(), "must be");
2630 // Remember this so we can avoid walking the hierarchy at runtime.
2631 set_verified_at_dump_time();
2632 }
2633
2634 Klass::remove_unshareable_info();
2635
2636 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2637 // Classes are attempted to link during dumping and may fail,
2638 // but these classes are still in the dictionary and class list in CLD.
2639 // If the class has failed verification, there is nothing else to remove.
2640 return;
2641 }
2642
2643 // Reset to the 'allocated' state to prevent any premature accessing to
2644 // a shared class at runtime while the class is still being loaded and
2645 // restored. A class' init_state is set to 'loaded' at runtime when it's
2646 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2647 _init_state = allocated;
2648
2649 { // Otherwise this needs to take out the Compile_lock.
2650 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2651 init_implementor();
2652 }
2653
2654 // Call remove_unshareable_info() on other objects that belong to this class, except
2655 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2656 // ArchiveBuilder::make_klasses_shareable(),
2657
2658 for (int i = 0; i < methods()->length(); i++) {
2659 Method* m = methods()->at(i);
2660 m->remove_unshareable_info();
2661 }
2662
2663 // do array classes also.
2664 if (array_klasses() != nullptr) {
2665 array_klasses()->remove_unshareable_info();
2666 }
2667
2668 // These are not allocated from metaspace. They are safe to set to null.
2669 _source_debug_extension = nullptr;
2670 _dep_context = nullptr;
2671 _osr_nmethods_head = nullptr;
2672 #if INCLUDE_JVMTI
2673 _breakpoints = nullptr;
2674 _previous_versions = nullptr;
2675 _cached_class_file = nullptr;
2676 _jvmti_cached_class_field_map = nullptr;
2677 #endif
2678
2679 _init_thread = nullptr;
2680 _methods_jmethod_ids = nullptr;
2681 _jni_ids = nullptr;
2682 _oop_map_cache = nullptr;
2683 if (CDSConfig::is_dumping_invokedynamic() && HeapShared::is_lambda_proxy_klass(this)) {
2684 // keep _nest_host
2685 } else {
2686 // clear _nest_host to ensure re-load at runtime
2687 _nest_host = nullptr;
2688 }
2689 init_shared_package_entry();
2690 _dep_context_last_cleaned = 0;
2691
2692 remove_unshareable_flags();
2693 }
2694
2695 void InstanceKlass::remove_unshareable_flags() {
2696 // clear all the flags/stats that shouldn't be in the archived version
2697 assert(!is_scratch_class(), "must be");
2698 assert(!has_been_redefined(), "must be");
2699 #if INCLUDE_JVMTI
2700 set_is_being_redefined(false);
2701 #endif
2702 set_has_resolved_methods(false);
2703 }
2704
2705 void InstanceKlass::remove_java_mirror() {
2706 Klass::remove_java_mirror();
2707
2708 // do array classes also.
2709 if (array_klasses() != nullptr) {
2710 array_klasses()->remove_java_mirror();
2711 }
2712 }
2713
2714 void InstanceKlass::init_shared_package_entry() {
2715 assert(CDSConfig::is_dumping_archive(), "must be");
2716 #if !INCLUDE_CDS_JAVA_HEAP
2717 _package_entry = nullptr;
2718 #else
2719 if (CDSConfig::is_dumping_full_module_graph()) {
2720 if (is_shared_unregistered_class()) {
2721 _package_entry = nullptr;
2722 } else {
2723 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2724 }
2725 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2726 CDSConfig::is_using_full_module_graph() &&
2727 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2728 // _package_entry is an archived package in the base archive. Leave it as is.
2729 } else {
2730 _package_entry = nullptr;
2731 }
2732 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2733 #endif
2734 }
2735
2736 void InstanceKlass::compute_has_loops_flag_for_methods() {
2737 Array<Method*>* methods = this->methods();
2738 for (int index = 0; index < methods->length(); ++index) {
2739 Method* m = methods->at(index);
2740 if (!m->is_overpass()) { // work around JDK-8305771
2741 m->compute_has_loops_flag();
2742 }
2743 }
2744 }
2745
2746 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2747 PackageEntry* pkg_entry, TRAPS) {
2748 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2749 // before the InstanceKlass is added to the SystemDictionary. Make
2750 // sure the current state is <loaded.
2751 assert(!is_loaded(), "invalid init state");
2752 assert(!shared_loading_failed(), "Must not try to load failed class again");
2753 set_package(loader_data, pkg_entry, CHECK);
2754 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2755
2756 Array<Method*>* methods = this->methods();
2757 int num_methods = methods->length();
2758 for (int index = 0; index < num_methods; ++index) {
2759 methods->at(index)->restore_unshareable_info(CHECK);
2760 }
2761 #if INCLUDE_JVMTI
2762 if (JvmtiExport::has_redefined_a_class()) {
2763 // Reinitialize vtable because RedefineClasses may have changed some
2764 // entries in this vtable for super classes so the CDS vtable might
2765 // point to old or obsolete entries. RedefineClasses doesn't fix up
2766 // vtables in the shared system dictionary, only the main one.
2767 // It also redefines the itable too so fix that too.
2768 // First fix any default methods that point to a super class that may
2769 // have been redefined.
2770 bool trace_name_printed = false;
2771 adjust_default_methods(&trace_name_printed);
2772 if (verified_at_dump_time()) {
2773 // Initialize vtable and itable for classes which can be verified at dump time.
2774 // Unlinked classes such as old classes with major version < 50 cannot be verified
2775 // at dump time.
2776 vtable().initialize_vtable();
2777 itable().initialize_itable();
2778 }
2779 }
2780 #endif // INCLUDE_JVMTI
2781
2782 // restore constant pool resolved references
2783 constants()->restore_unshareable_info(CHECK);
2784
2785 if (array_klasses() != nullptr) {
2786 // To get a consistent list of classes we need MultiArray_lock to ensure
2787 // array classes aren't observed while they are being restored.
2788 RecursiveLocker rl(MultiArray_lock, THREAD);
2789 assert(this == array_klasses()->bottom_klass(), "sanity");
2790 // Array classes have null protection domain.
2791 // --> see ArrayKlass::complete_create_array_klass()
2792 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2793 }
2794
2795 // Initialize @ValueBased class annotation if not already set in the archived klass.
2796 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2797 set_is_value_based();
2798 }
2799 }
2800
2801 // Check if a class or any of its supertypes has a version older than 50.
2802 // CDS will not perform verification of old classes during dump time because
2803 // without changing the old verifier, the verification constraint cannot be
2804 // retrieved during dump time.
2805 // Verification of archived old classes will be performed during run time.
2806 bool InstanceKlass::can_be_verified_at_dumptime() const {
2807 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2808 // This is a class that was dumped into the base archive, so we know
2809 // it was verified at dump time.
2810 return true;
2811 }
2812 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2813 return false;
2814 }
2815 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2816 return false;
2817 }
2818 Array<InstanceKlass*>* interfaces = local_interfaces();
2819 int len = interfaces->length();
2820 for (int i = 0; i < len; i++) {
2821 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2822 return false;
2823 }
2824 }
2825 return true;
2826 }
2827
2828 int InstanceKlass::shared_class_loader_type() const {
2829 if (is_shared_boot_class()) {
2830 return ClassLoader::BOOT_LOADER;
2831 } else if (is_shared_platform_class()) {
2832 return ClassLoader::PLATFORM_LOADER;
2833 } else if (is_shared_app_class()) {
2834 return ClassLoader::APP_LOADER;
2835 } else {
2836 return ClassLoader::OTHER;
2837 }
2838 }
2839 #endif // INCLUDE_CDS
2840
2841 #if INCLUDE_JVMTI
2842 static void clear_all_breakpoints(Method* m) {
2843 m->clear_all_breakpoints();
2844 }
2845 #endif
2846
2847 void InstanceKlass::unload_class(InstanceKlass* ik) {
2848
2849 if (ik->is_scratch_class()) {
2850 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2851 return;
2852 }
2853 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2854
2855 // Release dependencies.
2856 ik->dependencies().remove_all_dependents();
2857
2858 // notify the debugger
2859 if (JvmtiExport::should_post_class_unload()) {
2860 JvmtiExport::post_class_unload(ik);
2861 }
2862
2863 // notify ClassLoadingService of class unload
2864 ClassLoadingService::notify_class_unloaded(ik);
2865
2866 SystemDictionaryShared::handle_class_unloading(ik);
2867
2868 if (log_is_enabled(Info, class, unload)) {
2869 ResourceMark rm;
2870 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2871 }
2872
2873 Events::log_class_unloading(Thread::current(), ik);
2874
2875 #if INCLUDE_JFR
2876 assert(ik != nullptr, "invariant");
2877 EventClassUnload event;
2878 event.set_unloadedClass(ik);
2879 event.set_definingClassLoader(ik->class_loader_data());
2880 event.commit();
2881 #endif
2882 }
2883
2884 static void method_release_C_heap_structures(Method* m) {
2885 m->release_C_heap_structures();
2886 }
2887
2888 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2889 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2890 // Clean up C heap
2891 Klass::release_C_heap_structures();
2892
2893 // Deallocate and call destructors for MDO mutexes
2894 if (release_sub_metadata) {
2895 methods_do(method_release_C_heap_structures);
2896 }
2897
2898 // Deallocate oop map cache
2899 if (_oop_map_cache != nullptr) {
2900 delete _oop_map_cache;
2901 _oop_map_cache = nullptr;
2902 }
2903
2904 // Deallocate JNI identifiers for jfieldIDs
2905 JNIid::deallocate(jni_ids());
2906 set_jni_ids(nullptr);
2907
2908 jmethodID* jmeths = methods_jmethod_ids_acquire();
2909 if (jmeths != nullptr) {
2910 release_set_methods_jmethod_ids(nullptr);
2911 FreeHeap(jmeths);
2912 }
2913
2914 assert(_dep_context == nullptr,
2915 "dependencies should already be cleaned");
2916
2917 #if INCLUDE_JVMTI
2918 // Deallocate breakpoint records
2919 if (breakpoints() != nullptr) {
2920 methods_do(clear_all_breakpoints);
2921 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2922 }
2923
2924 // deallocate the cached class file
2925 if (_cached_class_file != nullptr) {
2926 os::free(_cached_class_file);
2927 _cached_class_file = nullptr;
2928 }
2929 #endif
2930
2931 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2932
2933 if (release_sub_metadata) {
2934 constants()->release_C_heap_structures();
2935 }
2936 }
2937
2938 // The constant pool is on stack if any of the methods are executing or
2939 // referenced by handles.
2940 bool InstanceKlass::on_stack() const {
2941 return _constants->on_stack();
2942 }
2943
2944 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
2945 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
2946 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
2947
2948 // minor and major version numbers of class file
2949 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
2950 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
2951 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
2952 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
2953
2954 InstanceKlass* InstanceKlass::get_klass_version(int version) {
2955 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
2956 if (ik->constants()->version() == version) {
2957 return ik;
2958 }
2959 }
2960 return nullptr;
2961 }
2962
2963 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2964 if (array == nullptr) {
2965 _source_debug_extension = nullptr;
2966 } else {
2967 // Adding one to the attribute length in order to store a null terminator
2968 // character could cause an overflow because the attribute length is
2969 // already coded with an u4 in the classfile, but in practice, it's
2970 // unlikely to happen.
2971 assert((length+1) > length, "Overflow checking");
2972 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2973 for (int i = 0; i < length; i++) {
2974 sde[i] = array[i];
2975 }
2976 sde[length] = '\0';
2977 _source_debug_extension = sde;
2978 }
2979 }
2980
2981 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
2982 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
2983 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
2984
2985 const char* InstanceKlass::signature_name() const {
2986
2987 // Get the internal name as a c string
2988 const char* src = (const char*) (name()->as_C_string());
2989 const int src_length = (int)strlen(src);
2990
2991 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
2992
2993 // Add L as type indicator
2994 int dest_index = 0;
2995 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2996
2997 // Add the actual class name
2998 for (int src_index = 0; src_index < src_length; ) {
2999 dest[dest_index++] = src[src_index++];
3000 }
3001
3002 if (is_hidden()) { // Replace the last '+' with a '.'.
3003 for (int index = (int)src_length; index > 0; index--) {
3004 if (dest[index] == '+') {
3005 dest[index] = JVM_SIGNATURE_DOT;
3006 break;
3007 }
3008 }
3009 }
3010
3011 // Add the semicolon and the null
3012 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3013 dest[dest_index] = '\0';
3014 return dest;
3015 }
3016
3017 ModuleEntry* InstanceKlass::module() const {
3018 if (is_hidden() &&
3019 in_unnamed_package() &&
3020 class_loader_data()->has_class_mirror_holder()) {
3021 // For a non-strong hidden class defined to an unnamed package,
3022 // its (class held) CLD will not have an unnamed module created for it.
3023 // Two choices to find the correct ModuleEntry:
3024 // 1. If hidden class is within a nest, use nest host's module
3025 // 2. Find the unnamed module off from the class loader
3026 // For now option #2 is used since a nest host is not set until
3027 // after the instance class is created in jvm_lookup_define_class().
3028 if (class_loader_data()->is_boot_class_loader_data()) {
3029 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3030 } else {
3031 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3032 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3033 return java_lang_Module::module_entry(module);
3034 }
3035 }
3036
3037 // Class is in a named package
3038 if (!in_unnamed_package()) {
3039 return _package_entry->module();
3040 }
3041
3042 // Class is in an unnamed package, return its loader's unnamed module
3043 return class_loader_data()->unnamed_module();
3044 }
3045
3046 bool InstanceKlass::in_javabase_module() const {
3047 return module()->name() == vmSymbols::java_base();
3048 }
3049
3050 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3051
3052 // ensure java/ packages only loaded by boot or platform builtin loaders
3053 // not needed for shared class since CDS does not archive prohibited classes.
3054 if (!is_shared()) {
3055 check_prohibited_package(name(), loader_data, CHECK);
3056 }
3057
3058 if (is_shared() && _package_entry != nullptr) {
3059 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3060 // we can use the saved package
3061 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3062 return;
3063 } else {
3064 _package_entry = nullptr;
3065 }
3066 }
3067
3068 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3069 // it returns, so we need to decrement it when the current function exits.
3070 TempNewSymbol from_class_name =
3071 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3072
3073 Symbol* pkg_name;
3074 if (pkg_entry != nullptr) {
3075 pkg_name = pkg_entry->name();
3076 } else {
3077 pkg_name = from_class_name;
3078 }
3079
3080 if (pkg_name != nullptr && loader_data != nullptr) {
3081
3082 // Find in class loader's package entry table.
3083 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3084
3085 // If the package name is not found in the loader's package
3086 // entry table, it is an indication that the package has not
3087 // been defined. Consider it defined within the unnamed module.
3088 if (_package_entry == nullptr) {
3089
3090 if (!ModuleEntryTable::javabase_defined()) {
3091 // Before java.base is defined during bootstrapping, define all packages in
3092 // the java.base module. If a non-java.base package is erroneously placed
3093 // in the java.base module it will be caught later when java.base
3094 // is defined by ModuleEntryTable::verify_javabase_packages check.
3095 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3096 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3097 } else {
3098 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3099 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3100 }
3101
3102 // A package should have been successfully created
3103 DEBUG_ONLY(ResourceMark rm(THREAD));
3104 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3105 name()->as_C_string(), loader_data->loader_name_and_id());
3106 }
3107
3108 if (log_is_enabled(Debug, module)) {
3109 ResourceMark rm(THREAD);
3110 ModuleEntry* m = _package_entry->module();
3111 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3112 external_name(),
3113 pkg_name->as_C_string(),
3114 loader_data->loader_name_and_id(),
3115 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3116 }
3117 } else {
3118 ResourceMark rm(THREAD);
3119 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3120 external_name(),
3121 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3122 UNNAMED_MODULE);
3123 }
3124 }
3125
3126 // Function set_classpath_index ensures that for a non-null _package_entry
3127 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3128 // It then sets the classpath_index in the package entry record.
3129 //
3130 // The classpath_index field is used to find the entry on the boot loader class
3131 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3132 // in an unnamed module. It is also used to indicate (for all packages whose
3133 // classes are loaded by the boot loader) that at least one of the package's
3134 // classes has been loaded.
3135 void InstanceKlass::set_classpath_index(s2 path_index) {
3136 if (_package_entry != nullptr) {
3137 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3138 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3139 assert(path_index != -1, "Unexpected classpath_index");
3140 _package_entry->set_classpath_index(path_index);
3141 }
3142 }
3143
3144 // different versions of is_same_class_package
3145
3146 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3147 oop classloader1 = this->class_loader();
3148 PackageEntry* classpkg1 = this->package();
3149 if (class2->is_objArray_klass()) {
3150 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3151 }
3152
3153 oop classloader2;
3154 PackageEntry* classpkg2;
3155 if (class2->is_instance_klass()) {
3156 classloader2 = class2->class_loader();
3157 classpkg2 = class2->package();
3158 } else {
3159 assert(class2->is_typeArray_klass(), "should be type array");
3160 classloader2 = nullptr;
3161 classpkg2 = nullptr;
3162 }
3163
3164 // Same package is determined by comparing class loader
3165 // and package entries. Both must be the same. This rule
3166 // applies even to classes that are defined in the unnamed
3167 // package, they still must have the same class loader.
3168 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3169 return true;
3170 }
3171
3172 return false;
3173 }
3174
3175 // return true if this class and other_class are in the same package. Classloader
3176 // and classname information is enough to determine a class's package
3177 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3178 const Symbol* other_class_name) const {
3179 if (class_loader() != other_class_loader) {
3180 return false;
3181 }
3182 if (name()->fast_compare(other_class_name) == 0) {
3183 return true;
3184 }
3185
3186 {
3187 ResourceMark rm;
3188
3189 bool bad_class_name = false;
3190 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3191 if (bad_class_name) {
3192 return false;
3193 }
3194 // Check that package_from_class_name() returns null, not "", if there is no package.
3195 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3196
3197 const Symbol* const this_package_name =
3198 this->package() != nullptr ? this->package()->name() : nullptr;
3199
3200 if (this_package_name == nullptr || other_pkg == nullptr) {
3201 // One of the two doesn't have a package. Only return true if the other
3202 // one also doesn't have a package.
3203 return this_package_name == other_pkg;
3204 }
3205
3206 // Check if package is identical
3207 return this_package_name->fast_compare(other_pkg) == 0;
3208 }
3209 }
3210
3211 static bool is_prohibited_package_slow(Symbol* class_name) {
3212 // Caller has ResourceMark
3213 int length;
3214 jchar* unicode = class_name->as_unicode(length);
3215 return (length >= 5 &&
3216 unicode[0] == 'j' &&
3217 unicode[1] == 'a' &&
3218 unicode[2] == 'v' &&
3219 unicode[3] == 'a' &&
3220 unicode[4] == '/');
3221 }
3222
3223 // Only boot and platform class loaders can define classes in "java/" packages.
3224 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3225 ClassLoaderData* loader_data,
3226 TRAPS) {
3227 if (!loader_data->is_boot_class_loader_data() &&
3228 !loader_data->is_platform_class_loader_data() &&
3229 class_name != nullptr && class_name->utf8_length() >= 5) {
3230 ResourceMark rm(THREAD);
3231 bool prohibited;
3232 const u1* base = class_name->base();
3233 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3234 prohibited = is_prohibited_package_slow(class_name);
3235 } else {
3236 char* name = class_name->as_C_string();
3237 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3238 }
3239 if (prohibited) {
3240 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3241 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3242 char* name = pkg_name->as_C_string();
3243 const char* class_loader_name = loader_data->loader_name_and_id();
3244 StringUtils::replace_no_expand(name, "/", ".");
3245 const char* msg_text1 = "Class loader (instance of): ";
3246 const char* msg_text2 = " tried to load prohibited package name: ";
3247 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3248 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3249 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3250 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3251 }
3252 }
3253 return;
3254 }
3255
3256 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3257 constantPoolHandle i_cp(THREAD, constants());
3258 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3259 int ioff = iter.inner_class_info_index();
3260 if (ioff != 0) {
3261 // Check to see if the name matches the class we're looking for
3262 // before attempting to find the class.
3263 if (i_cp->klass_name_at_matches(this, ioff)) {
3264 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3265 if (this == inner_klass) {
3266 *ooff = iter.outer_class_info_index();
3267 *noff = iter.inner_name_index();
3268 return true;
3269 }
3270 }
3271 }
3272 }
3273 return false;
3274 }
3275
3276 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3277 InstanceKlass* outer_klass = nullptr;
3278 *inner_is_member = false;
3279 int ooff = 0, noff = 0;
3280 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3281 if (has_inner_classes_attr) {
3282 constantPoolHandle i_cp(THREAD, constants());
3283 if (ooff != 0) {
3284 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3285 if (!ok->is_instance_klass()) {
3286 // If the outer class is not an instance klass then it cannot have
3287 // declared any inner classes.
3288 ResourceMark rm(THREAD);
3289 Exceptions::fthrow(
3290 THREAD_AND_LOCATION,
3291 vmSymbols::java_lang_IncompatibleClassChangeError(),
3292 "%s and %s disagree on InnerClasses attribute",
3293 ok->external_name(),
3294 external_name());
3295 return nullptr;
3296 }
3297 outer_klass = InstanceKlass::cast(ok);
3298 *inner_is_member = true;
3299 }
3300 if (nullptr == outer_klass) {
3301 // It may be a local class; try for that.
3302 int encl_method_class_idx = enclosing_method_class_index();
3303 if (encl_method_class_idx != 0) {
3304 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3305 outer_klass = InstanceKlass::cast(ok);
3306 *inner_is_member = false;
3307 }
3308 }
3309 }
3310
3311 // If no inner class attribute found for this class.
3312 if (nullptr == outer_klass) return nullptr;
3313
3314 // Throws an exception if outer klass has not declared k as an inner klass
3315 // We need evidence that each klass knows about the other, or else
3316 // the system could allow a spoof of an inner class to gain access rights.
3317 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3318 return outer_klass;
3319 }
3320
3321 jint InstanceKlass::compute_modifier_flags() const {
3322 jint access = access_flags().as_int();
3323
3324 // But check if it happens to be member class.
3325 InnerClassesIterator iter(this);
3326 for (; !iter.done(); iter.next()) {
3327 int ioff = iter.inner_class_info_index();
3328 // Inner class attribute can be zero, skip it.
3329 // Strange but true: JVM spec. allows null inner class refs.
3330 if (ioff == 0) continue;
3331
3332 // only look at classes that are already loaded
3333 // since we are looking for the flags for our self.
3334 Symbol* inner_name = constants()->klass_name_at(ioff);
3335 if (name() == inner_name) {
3336 // This is really a member class.
3337 access = iter.inner_access_flags();
3338 break;
3339 }
3340 }
3341 // Remember to strip ACC_SUPER bit
3342 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3343 }
3344
3345 jint InstanceKlass::jvmti_class_status() const {
3346 jint result = 0;
3347
3348 if (is_linked()) {
3349 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3350 }
3351
3352 if (is_initialized()) {
3353 assert(is_linked(), "Class status is not consistent");
3354 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3355 }
3356 if (is_in_error_state()) {
3357 result |= JVMTI_CLASS_STATUS_ERROR;
3358 }
3359 return result;
3360 }
3361
3362 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3363 bool implements_interface; // initialized by method_at_itable_or_null
3364 Method* m = method_at_itable_or_null(holder, index,
3365 implements_interface); // out parameter
3366 if (m != nullptr) {
3367 assert(implements_interface, "sanity");
3368 return m;
3369 } else if (implements_interface) {
3370 // Throw AbstractMethodError since corresponding itable slot is empty.
3371 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3372 } else {
3373 // If the interface isn't implemented by the receiver class,
3374 // the VM should throw IncompatibleClassChangeError.
3375 ResourceMark rm(THREAD);
3376 stringStream ss;
3377 bool same_module = (module() == holder->module());
3378 ss.print("Receiver class %s does not implement "
3379 "the interface %s defining the method to be called "
3380 "(%s%s%s)",
3381 external_name(), holder->external_name(),
3382 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3383 (same_module) ? "" : "; ",
3384 (same_module) ? "" : holder->class_in_module_of_loader());
3385 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3386 }
3387 }
3388
3389 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3390 klassItable itable(this);
3391 for (int i = 0; i < itable.size_offset_table(); i++) {
3392 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3393 if (offset_entry->interface_klass() == holder) {
3394 implements_interface = true;
3395 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3396 Method* m = ime[index].method();
3397 return m;
3398 }
3399 }
3400 implements_interface = false;
3401 return nullptr; // offset entry not found
3402 }
3403
3404 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3405 assert(is_linked(), "required");
3406 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3407 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3408
3409 int vtable_index = Method::invalid_vtable_index;
3410 Symbol* name = intf_method->name();
3411 Symbol* signature = intf_method->signature();
3412
3413 // First check in default method array
3414 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3415 int index = find_method_index(default_methods(),
3416 name, signature,
3417 Klass::OverpassLookupMode::find,
3418 Klass::StaticLookupMode::find,
3419 Klass::PrivateLookupMode::find);
3420 if (index >= 0) {
3421 vtable_index = default_vtable_indices()->at(index);
3422 }
3423 }
3424 if (vtable_index == Method::invalid_vtable_index) {
3425 // get vtable_index for miranda methods
3426 klassVtable vt = vtable();
3427 vtable_index = vt.index_of_miranda(name, signature);
3428 }
3429 return vtable_index;
3430 }
3431
3432 #if INCLUDE_JVMTI
3433 // update default_methods for redefineclasses for methods that are
3434 // not yet in the vtable due to concurrent subclass define and superinterface
3435 // redefinition
3436 // Note: those in the vtable, should have been updated via adjust_method_entries
3437 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3438 // search the default_methods for uses of either obsolete or EMCP methods
3439 if (default_methods() != nullptr) {
3440 for (int index = 0; index < default_methods()->length(); index ++) {
3441 Method* old_method = default_methods()->at(index);
3442 if (old_method == nullptr || !old_method->is_old()) {
3443 continue; // skip uninteresting entries
3444 }
3445 assert(!old_method->is_deleted(), "default methods may not be deleted");
3446 Method* new_method = old_method->get_new_method();
3447 default_methods()->at_put(index, new_method);
3448
3449 if (log_is_enabled(Info, redefine, class, update)) {
3450 ResourceMark rm;
3451 if (!(*trace_name_printed)) {
3452 log_info(redefine, class, update)
3453 ("adjust: klassname=%s default methods from name=%s",
3454 external_name(), old_method->method_holder()->external_name());
3455 *trace_name_printed = true;
3456 }
3457 log_debug(redefine, class, update, vtables)
3458 ("default method update: %s(%s) ",
3459 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3460 }
3461 }
3462 }
3463 }
3464 #endif // INCLUDE_JVMTI
3465
3466 // On-stack replacement stuff
3467 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3468 assert_lock_strong(NMethodState_lock);
3469 #ifndef PRODUCT
3470 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3471 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3472 "redundant OSR recompilation detected. memory leak in CodeCache!");
3473 #endif
3474 // only one compilation can be active
3475 assert(n->is_osr_method(), "wrong kind of nmethod");
3476 n->set_osr_link(osr_nmethods_head());
3477 set_osr_nmethods_head(n);
3478 // Raise the highest osr level if necessary
3479 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3480
3481 // Get rid of the osr methods for the same bci that have lower levels.
3482 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3483 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3484 if (inv != nullptr && inv->is_in_use()) {
3485 inv->make_not_entrant();
3486 }
3487 }
3488 }
3489
3490 // Remove osr nmethod from the list. Return true if found and removed.
3491 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3492 // This is a short non-blocking critical region, so the no safepoint check is ok.
3493 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3494 assert(n->is_osr_method(), "wrong kind of nmethod");
3495 nmethod* last = nullptr;
3496 nmethod* cur = osr_nmethods_head();
3497 int max_level = CompLevel_none; // Find the max comp level excluding n
3498 Method* m = n->method();
3499 // Search for match
3500 bool found = false;
3501 while(cur != nullptr && cur != n) {
3502 if (m == cur->method()) {
3503 // Find max level before n
3504 max_level = MAX2(max_level, cur->comp_level());
3505 }
3506 last = cur;
3507 cur = cur->osr_link();
3508 }
3509 nmethod* next = nullptr;
3510 if (cur == n) {
3511 found = true;
3512 next = cur->osr_link();
3513 if (last == nullptr) {
3514 // Remove first element
3515 set_osr_nmethods_head(next);
3516 } else {
3517 last->set_osr_link(next);
3518 }
3519 }
3520 n->set_osr_link(nullptr);
3521 cur = next;
3522 while (cur != nullptr) {
3523 // Find max level after n
3524 if (m == cur->method()) {
3525 max_level = MAX2(max_level, cur->comp_level());
3526 }
3527 cur = cur->osr_link();
3528 }
3529 m->set_highest_osr_comp_level(max_level);
3530 return found;
3531 }
3532
3533 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3534 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3535 nmethod* osr = osr_nmethods_head();
3536 int found = 0;
3537 while (osr != nullptr) {
3538 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3539 if (osr->method() == m) {
3540 deopt_scope->mark(osr);
3541 found++;
3542 }
3543 osr = osr->osr_link();
3544 }
3545 return found;
3546 }
3547
3548 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3549 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3550 nmethod* osr = osr_nmethods_head();
3551 nmethod* best = nullptr;
3552 while (osr != nullptr) {
3553 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3554 // There can be a time when a c1 osr method exists but we are waiting
3555 // for a c2 version. When c2 completes its osr nmethod we will trash
3556 // the c1 version and only be able to find the c2 version. However
3557 // while we overflow in the c1 code at back branches we don't want to
3558 // try and switch to the same code as we are already running
3559
3560 if (osr->method() == m &&
3561 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3562 if (match_level) {
3563 if (osr->comp_level() == comp_level) {
3564 // Found a match - return it.
3565 return osr;
3566 }
3567 } else {
3568 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3569 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3570 // Found the best possible - return it.
3571 return osr;
3572 }
3573 best = osr;
3574 }
3575 }
3576 }
3577 osr = osr->osr_link();
3578 }
3579
3580 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3581 if (best != nullptr && best->comp_level() >= comp_level) {
3582 return best;
3583 }
3584 return nullptr;
3585 }
3586
3587 // -----------------------------------------------------------------------------------------------------
3588 // Printing
3589
3590 #define BULLET " - "
3591
3592 static const char* state_names[] = {
3593 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3594 };
3595
3596 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3597 for (int i = 0; i < len; i++) {
3598 intptr_t e = start[i];
3599 st->print("%d : " INTPTR_FORMAT, i, e);
3600 if (MetaspaceObj::is_valid((Metadata*)e)) {
3601 st->print(" ");
3602 ((Metadata*)e)->print_value_on(st);
3603 }
3604 st->cr();
3605 }
3606 }
3607
3608 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3609 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3610 }
3611
3612 const char* InstanceKlass::init_state_name() const {
3613 return state_names[init_state()];
3614 }
3615
3616 void InstanceKlass::print_on(outputStream* st) const {
3617 assert(is_klass(), "must be klass");
3618 Klass::print_on(st);
3619
3620 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3621 st->print(BULLET"klass size: %d", size()); st->cr();
3622 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3623 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3624 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3625 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3626 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3627 st->print(BULLET"sub: ");
3628 Klass* sub = subklass();
3629 int n;
3630 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3631 if (n < MaxSubklassPrintSize) {
3632 sub->print_value_on(st);
3633 st->print(" ");
3634 }
3635 }
3636 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3637 st->cr();
3638
3639 if (is_interface()) {
3640 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3641 if (nof_implementors() == 1) {
3642 st->print_cr(BULLET"implementor: ");
3643 st->print(" ");
3644 implementor()->print_value_on(st);
3645 st->cr();
3646 }
3647 }
3648
3649 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3650 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3651 if (Verbose || WizardMode) {
3652 Array<Method*>* method_array = methods();
3653 for (int i = 0; i < method_array->length(); i++) {
3654 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3655 }
3656 }
3657 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3658 if (default_methods() != nullptr) {
3659 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3660 if (Verbose) {
3661 Array<Method*>* method_array = default_methods();
3662 for (int i = 0; i < method_array->length(); i++) {
3663 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3664 }
3665 }
3666 }
3667 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3668 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3669 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3670
3671 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3672
3673 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3674 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3675
3676 if (secondary_supers() != nullptr) {
3677 if (Verbose) {
3678 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3679 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3680 for (int i = 0; i < _secondary_supers->length(); i++) {
3681 ResourceMark rm; // for external_name()
3682 Klass* secondary_super = _secondary_supers->at(i);
3683 st->print(BULLET"%2d:", i);
3684 if (is_hashed) {
3685 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3686 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3687 st->print(" dist:%02d:", distance);
3688 }
3689 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3690 }
3691 }
3692 }
3693 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3694
3695 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3696 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3697 if (source_debug_extension() != nullptr) {
3698 st->print(BULLET"source debug extension: ");
3699 st->print("%s", source_debug_extension());
3700 st->cr();
3701 }
3702 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3703 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3704 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3705 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3706 {
3707 bool have_pv = false;
3708 // previous versions are linked together through the InstanceKlass
3709 for (InstanceKlass* pv_node = previous_versions();
3710 pv_node != nullptr;
3711 pv_node = pv_node->previous_versions()) {
3712 if (!have_pv)
3713 st->print(BULLET"previous version: ");
3714 have_pv = true;
3715 pv_node->constants()->print_value_on(st);
3716 }
3717 if (have_pv) st->cr();
3718 }
3719
3720 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3721 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3722 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3723 print_on_maybe_null(st, BULLET"record components: ", record_components());
3724 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3725 if (java_mirror() != nullptr) {
3726 st->print(BULLET"java mirror: ");
3727 java_mirror()->print_value_on(st);
3728 st->cr();
3729 } else {
3730 st->print_cr(BULLET"java mirror: null");
3731 }
3732 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3733 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3734 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3735 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3736 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3737
3738 FieldPrinter print_static_field(st);
3739 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3740 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3741 FieldPrinter print_nonstatic_field(st);
3742 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3743 ik->print_nonstatic_fields(&print_nonstatic_field);
3744
3745 st->print(BULLET"non-static oop maps: ");
3746 OopMapBlock* map = start_of_nonstatic_oop_maps();
3747 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3748 while (map < end_map) {
3749 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3750 map++;
3751 }
3752 st->cr();
3753 }
3754
3755 void InstanceKlass::print_value_on(outputStream* st) const {
3756 assert(is_klass(), "must be klass");
3757 if (Verbose || WizardMode) access_flags().print_on(st);
3758 name()->print_value_on(st);
3759 }
3760
3761 void FieldPrinter::do_field(fieldDescriptor* fd) {
3762 _st->print(BULLET);
3763 if (_obj == nullptr) {
3764 fd->print_on(_st);
3765 _st->cr();
3766 } else {
3767 fd->print_on_for(_st, _obj);
3768 _st->cr();
3769 }
3770 }
3771
3772
3773 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3774 Klass::oop_print_on(obj, st);
3775
3776 if (this == vmClasses::String_klass()) {
3777 typeArrayOop value = java_lang_String::value(obj);
3778 juint length = java_lang_String::length(obj);
3779 if (value != nullptr &&
3780 value->is_typeArray() &&
3781 length <= (juint) value->length()) {
3782 st->print(BULLET"string: ");
3783 java_lang_String::print(obj, st);
3784 st->cr();
3785 }
3786 }
3787
3788 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3789 FieldPrinter print_field(st, obj);
3790 print_nonstatic_fields(&print_field);
3791
3792 if (this == vmClasses::Class_klass()) {
3793 st->print(BULLET"signature: ");
3794 java_lang_Class::print_signature(obj, st);
3795 st->cr();
3796 Klass* real_klass = java_lang_Class::as_Klass(obj);
3797 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3798 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3799 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3800 }
3801 } else if (this == vmClasses::MethodType_klass()) {
3802 st->print(BULLET"signature: ");
3803 java_lang_invoke_MethodType::print_signature(obj, st);
3804 st->cr();
3805 }
3806 }
3807
3808 #ifndef PRODUCT
3809
3810 bool InstanceKlass::verify_itable_index(int i) {
3811 int method_count = klassItable::method_count_for_interface(this);
3812 assert(i >= 0 && i < method_count, "index out of bounds");
3813 return true;
3814 }
3815
3816 #endif //PRODUCT
3817
3818 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3819 st->print("a ");
3820 name()->print_value_on(st);
3821 obj->print_address_on(st);
3822 if (this == vmClasses::String_klass()
3823 && java_lang_String::value(obj) != nullptr) {
3824 ResourceMark rm;
3825 int len = java_lang_String::length(obj);
3826 int plen = (len < 24 ? len : 12);
3827 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3828 st->print(" = \"%s\"", str);
3829 if (len > plen)
3830 st->print("...[%d]", len);
3831 } else if (this == vmClasses::Class_klass()) {
3832 Klass* k = java_lang_Class::as_Klass(obj);
3833 st->print(" = ");
3834 if (k != nullptr) {
3835 k->print_value_on(st);
3836 } else {
3837 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3838 st->print("%s", tname ? tname : "type?");
3839 }
3840 } else if (this == vmClasses::MethodType_klass()) {
3841 st->print(" = ");
3842 java_lang_invoke_MethodType::print_signature(obj, st);
3843 } else if (java_lang_boxing_object::is_instance(obj)) {
3844 st->print(" = ");
3845 java_lang_boxing_object::print(obj, st);
3846 } else if (this == vmClasses::LambdaForm_klass()) {
3847 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3848 if (vmentry != nullptr) {
3849 st->print(" => ");
3850 vmentry->print_value_on(st);
3851 }
3852 } else if (this == vmClasses::MemberName_klass()) {
3853 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3854 if (vmtarget != nullptr) {
3855 st->print(" = ");
3856 vmtarget->print_value_on(st);
3857 } else {
3858 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3859 oop name = java_lang_invoke_MemberName::name(obj);
3860 if (clazz != nullptr) {
3861 clazz->print_value_on(st);
3862 } else {
3863 st->print("null");
3864 }
3865 st->print(".");
3866 if (name != nullptr) {
3867 name->print_value_on(st);
3868 } else {
3869 st->print("null");
3870 }
3871 }
3872 }
3873 }
3874
3875 const char* InstanceKlass::internal_name() const {
3876 return external_name();
3877 }
3878
3879 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3880 const ModuleEntry* module_entry,
3881 const ClassFileStream* cfs) const {
3882
3883 if (ClassListWriter::is_enabled()) {
3884 ClassListWriter::write(this, cfs);
3885 }
3886
3887 print_class_load_helper(loader_data, module_entry, cfs);
3888 print_class_load_cause_logging();
3889 }
3890
3891 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3892 const ModuleEntry* module_entry,
3893 const ClassFileStream* cfs) const {
3894
3895 if (!log_is_enabled(Info, class, load)) {
3896 return;
3897 }
3898
3899 ResourceMark rm;
3900 LogMessage(class, load) msg;
3901 stringStream info_stream;
3902
3903 // Name and class hierarchy info
3904 info_stream.print("%s", external_name());
3905
3906 // Source
3907 if (cfs != nullptr) {
3908 if (cfs->source() != nullptr) {
3909 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3910 if (module_name != nullptr) {
3911 // When the boot loader created the stream, it didn't know the module name
3912 // yet. Let's format it now.
3913 if (cfs->from_boot_loader_modules_image()) {
3914 info_stream.print(" source: jrt:/%s", module_name);
3915 } else {
3916 info_stream.print(" source: %s", cfs->source());
3917 }
3918 } else {
3919 info_stream.print(" source: %s", cfs->source());
3920 }
3921 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3922 Thread* current = Thread::current();
3923 Klass* caller = current->is_Java_thread() ?
3924 JavaThread::cast(current)->security_get_caller_class(1):
3925 nullptr;
3926 // caller can be null, for example, during a JVMTI VM_Init hook
3927 if (caller != nullptr) {
3928 info_stream.print(" source: instance of %s", caller->external_name());
3929 } else {
3930 // source is unknown
3931 }
3932 } else {
3933 oop class_loader = loader_data->class_loader();
3934 info_stream.print(" source: %s", class_loader->klass()->external_name());
3935 }
3936 } else {
3937 assert(this->is_shared(), "must be");
3938 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3939 info_stream.print(" source: shared objects file (top)");
3940 } else {
3941 info_stream.print(" source: shared objects file");
3942 }
3943 }
3944
3945 msg.info("%s", info_stream.as_string());
3946
3947 if (log_is_enabled(Debug, class, load)) {
3948 stringStream debug_stream;
3949
3950 // Class hierarchy info
3951 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
3952 p2i(this), p2i(superklass()));
3953
3954 // Interfaces
3955 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
3956 debug_stream.print(" interfaces:");
3957 int length = local_interfaces()->length();
3958 for (int i = 0; i < length; i++) {
3959 debug_stream.print(" " PTR_FORMAT,
3960 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3961 }
3962 }
3963
3964 // Class loader
3965 debug_stream.print(" loader: [");
3966 loader_data->print_value_on(&debug_stream);
3967 debug_stream.print("]");
3968
3969 // Classfile checksum
3970 if (cfs) {
3971 debug_stream.print(" bytes: %d checksum: %08x",
3972 cfs->length(),
3973 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3974 cfs->length()));
3975 }
3976
3977 msg.debug("%s", debug_stream.as_string());
3978 }
3979 }
3980
3981 void InstanceKlass::print_class_load_cause_logging() const {
3982 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
3983 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
3984 JavaThread* current = JavaThread::current();
3985 ResourceMark rm(current);
3986 const char* name = external_name();
3987
3988 if (LogClassLoadingCauseFor == nullptr ||
3989 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
3990 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
3991 return;
3992 }
3993
3994 // Log Java stack first
3995 {
3996 LogMessage(class, load, cause) msg;
3997 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
3998
3999 info_stream.print_cr("Java stack when loading %s:", name);
4000 current->print_stack_on(&info_stream);
4001 }
4002
4003 // Log native stack second
4004 if (log_cause_native) {
4005 // Log to string first so that lines can be indented
4006 stringStream stack_stream;
4007 char buf[O_BUFLEN];
4008 address lastpc = nullptr;
4009 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4010 // We have printed the native stack in platform-specific code,
4011 // so nothing else to do in this case.
4012 } else {
4013 frame f = os::current_frame();
4014 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4015 -1 /* max stack_stream */, buf, O_BUFLEN);
4016 }
4017
4018 LogMessage(class, load, cause, native) msg;
4019 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4020 info_stream.print_cr("Native stack when loading %s:", name);
4021
4022 // Print each native stack line to the log
4023 int size = (int) stack_stream.size();
4024 char* stack = stack_stream.as_string();
4025 char* stack_end = stack + size;
4026 char* line_start = stack;
4027 for (char* p = stack; p < stack_end; p++) {
4028 if (*p == '\n') {
4029 *p = '\0';
4030 info_stream.print_cr("\t%s", line_start);
4031 line_start = p + 1;
4032 }
4033 }
4034 if (line_start < stack_end) {
4035 info_stream.print_cr("\t%s", line_start);
4036 }
4037 }
4038 }
4039 }
4040
4041 // Verification
4042
4043 class VerifyFieldClosure: public BasicOopIterateClosure {
4044 protected:
4045 template <class T> void do_oop_work(T* p) {
4046 oop obj = RawAccess<>::oop_load(p);
4047 if (!oopDesc::is_oop_or_null(obj)) {
4048 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4049 Universe::print_on(tty);
4050 guarantee(false, "boom");
4051 }
4052 }
4053 public:
4054 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4055 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4056 };
4057
4058 void InstanceKlass::verify_on(outputStream* st) {
4059 #ifndef PRODUCT
4060 // Avoid redundant verifies, this really should be in product.
4061 if (_verify_count == Universe::verify_count()) return;
4062 _verify_count = Universe::verify_count();
4063 #endif
4064
4065 // Verify Klass
4066 Klass::verify_on(st);
4067
4068 // Verify that klass is present in ClassLoaderData
4069 guarantee(class_loader_data()->contains_klass(this),
4070 "this class isn't found in class loader data");
4071
4072 // Verify vtables
4073 if (is_linked()) {
4074 // $$$ This used to be done only for m/s collections. Doing it
4075 // always seemed a valid generalization. (DLD -- 6/00)
4076 vtable().verify(st);
4077 }
4078
4079 // Verify first subklass
4080 if (subklass() != nullptr) {
4081 guarantee(subklass()->is_klass(), "should be klass");
4082 }
4083
4084 // Verify siblings
4085 Klass* super = this->super();
4086 Klass* sib = next_sibling();
4087 if (sib != nullptr) {
4088 if (sib == this) {
4089 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4090 }
4091
4092 guarantee(sib->is_klass(), "should be klass");
4093 guarantee(sib->super() == super, "siblings should have same superklass");
4094 }
4095
4096 // Verify local interfaces
4097 if (local_interfaces()) {
4098 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4099 for (int j = 0; j < local_interfaces->length(); j++) {
4100 InstanceKlass* e = local_interfaces->at(j);
4101 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4102 }
4103 }
4104
4105 // Verify transitive interfaces
4106 if (transitive_interfaces() != nullptr) {
4107 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4108 for (int j = 0; j < transitive_interfaces->length(); j++) {
4109 InstanceKlass* e = transitive_interfaces->at(j);
4110 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4111 }
4112 }
4113
4114 // Verify methods
4115 if (methods() != nullptr) {
4116 Array<Method*>* methods = this->methods();
4117 for (int j = 0; j < methods->length(); j++) {
4118 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4119 }
4120 for (int j = 0; j < methods->length() - 1; j++) {
4121 Method* m1 = methods->at(j);
4122 Method* m2 = methods->at(j + 1);
4123 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4124 }
4125 }
4126
4127 // Verify method ordering
4128 if (method_ordering() != nullptr) {
4129 Array<int>* method_ordering = this->method_ordering();
4130 int length = method_ordering->length();
4131 if (JvmtiExport::can_maintain_original_method_order() ||
4132 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4133 guarantee(length == methods()->length(), "invalid method ordering length");
4134 jlong sum = 0;
4135 for (int j = 0; j < length; j++) {
4136 int original_index = method_ordering->at(j);
4137 guarantee(original_index >= 0, "invalid method ordering index");
4138 guarantee(original_index < length, "invalid method ordering index");
4139 sum += original_index;
4140 }
4141 // Verify sum of indices 0,1,...,length-1
4142 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4143 } else {
4144 guarantee(length == 0, "invalid method ordering length");
4145 }
4146 }
4147
4148 // Verify default methods
4149 if (default_methods() != nullptr) {
4150 Array<Method*>* methods = this->default_methods();
4151 for (int j = 0; j < methods->length(); j++) {
4152 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4153 }
4154 for (int j = 0; j < methods->length() - 1; j++) {
4155 Method* m1 = methods->at(j);
4156 Method* m2 = methods->at(j + 1);
4157 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4158 }
4159 }
4160
4161 // Verify JNI static field identifiers
4162 if (jni_ids() != nullptr) {
4163 jni_ids()->verify(this);
4164 }
4165
4166 // Verify other fields
4167 if (constants() != nullptr) {
4168 guarantee(constants()->is_constantPool(), "should be constant pool");
4169 }
4170 }
4171
4172 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4173 Klass::oop_verify_on(obj, st);
4174 VerifyFieldClosure blk;
4175 obj->oop_iterate(&blk);
4176 }
4177
4178
4179 // JNIid class for jfieldIDs only
4180 // Note to reviewers:
4181 // These JNI functions are just moved over to column 1 and not changed
4182 // in the compressed oops workspace.
4183 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4184 _holder = holder;
4185 _offset = offset;
4186 _next = next;
4187 debug_only(_is_static_field_id = false;)
4188 }
4189
4190
4191 JNIid* JNIid::find(int offset) {
4192 JNIid* current = this;
4193 while (current != nullptr) {
4194 if (current->offset() == offset) return current;
4195 current = current->next();
4196 }
4197 return nullptr;
4198 }
4199
4200 void JNIid::deallocate(JNIid* current) {
4201 while (current != nullptr) {
4202 JNIid* next = current->next();
4203 delete current;
4204 current = next;
4205 }
4206 }
4207
4208
4209 void JNIid::verify(Klass* holder) {
4210 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4211 int end_field_offset;
4212 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4213
4214 JNIid* current = this;
4215 while (current != nullptr) {
4216 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4217 #ifdef ASSERT
4218 int o = current->offset();
4219 if (current->is_static_field_id()) {
4220 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4221 }
4222 #endif
4223 current = current->next();
4224 }
4225 }
4226
4227 void InstanceKlass::set_init_state(ClassState state) {
4228 #ifdef ASSERT
4229 bool good_state = is_shared() ? (_init_state <= state)
4230 : (_init_state < state);
4231 assert(good_state || state == allocated, "illegal state transition");
4232 #endif
4233 assert(_init_thread == nullptr, "should be cleared before state change");
4234 Atomic::release_store(&_init_state, state);
4235 }
4236
4237 #if INCLUDE_JVMTI
4238
4239 // RedefineClasses() support for previous versions
4240
4241 // Globally, there is at least one previous version of a class to walk
4242 // during class unloading, which is saved because old methods in the class
4243 // are still running. Otherwise the previous version list is cleaned up.
4244 bool InstanceKlass::_should_clean_previous_versions = false;
4245
4246 // Returns true if there are previous versions of a class for class
4247 // unloading only. Also resets the flag to false. purge_previous_version
4248 // will set the flag to true if there are any left, i.e., if there's any
4249 // work to do for next time. This is to avoid the expensive code cache
4250 // walk in CLDG::clean_deallocate_lists().
4251 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4252 bool ret = _should_clean_previous_versions;
4253 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4254 ret ? "true" : "false");
4255 _should_clean_previous_versions = false;
4256 return ret;
4257 }
4258
4259 // This nulls out jmethodIDs for all methods in 'klass'
4260 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4261 // during class unloading.
4262 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4263 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4264 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4265 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4266 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4267 Array<Method*>* method_refs = klass->methods();
4268 for (int k = 0; k < method_refs->length(); k++) {
4269 Method* method = method_refs->at(k);
4270 if (method != nullptr && method->is_obsolete()) {
4271 method->clear_jmethod_id();
4272 }
4273 }
4274 }
4275
4276 // Purge previous versions before adding new previous versions of the class and
4277 // during class unloading.
4278 void InstanceKlass::purge_previous_version_list() {
4279 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4280 assert(has_been_redefined(), "Should only be called for main class");
4281
4282 // Quick exit.
4283 if (previous_versions() == nullptr) {
4284 return;
4285 }
4286
4287 // This klass has previous versions so see what we can cleanup
4288 // while it is safe to do so.
4289
4290 int deleted_count = 0; // leave debugging breadcrumbs
4291 int live_count = 0;
4292 ClassLoaderData* loader_data = class_loader_data();
4293 assert(loader_data != nullptr, "should never be null");
4294
4295 ResourceMark rm;
4296 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4297
4298 // previous versions are linked together through the InstanceKlass
4299 InstanceKlass* pv_node = previous_versions();
4300 InstanceKlass* last = this;
4301 int version = 0;
4302
4303 // check the previous versions list
4304 for (; pv_node != nullptr; ) {
4305
4306 ConstantPool* pvcp = pv_node->constants();
4307 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4308
4309 if (!pvcp->on_stack()) {
4310 // If the constant pool isn't on stack, none of the methods
4311 // are executing. Unlink this previous_version.
4312 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4313 // so will be deallocated during the next phase of class unloading.
4314 log_trace(redefine, class, iklass, purge)
4315 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4316 // Unlink from previous version list.
4317 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4318 InstanceKlass* next = pv_node->previous_versions();
4319 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4320 pv_node->link_previous_versions(nullptr); // point next to null
4321 last->link_previous_versions(next);
4322 // Delete this node directly. Nothing is referring to it and we don't
4323 // want it to increase the counter for metadata to delete in CLDG.
4324 MetadataFactory::free_metadata(loader_data, pv_node);
4325 pv_node = next;
4326 deleted_count++;
4327 version++;
4328 continue;
4329 } else {
4330 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4331 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4332 live_count++;
4333 if (pvcp->is_shared()) {
4334 // Shared previous versions can never be removed so no cleaning is needed.
4335 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4336 } else {
4337 // Previous version alive, set that clean is needed for next time.
4338 _should_clean_previous_versions = true;
4339 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4340 }
4341 }
4342
4343 // next previous version
4344 last = pv_node;
4345 pv_node = pv_node->previous_versions();
4346 version++;
4347 }
4348 log_trace(redefine, class, iklass, purge)
4349 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4350 }
4351
4352 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4353 int emcp_method_count) {
4354 int obsolete_method_count = old_methods->length() - emcp_method_count;
4355
4356 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4357 _previous_versions != nullptr) {
4358 // We have a mix of obsolete and EMCP methods so we have to
4359 // clear out any matching EMCP method entries the hard way.
4360 int local_count = 0;
4361 for (int i = 0; i < old_methods->length(); i++) {
4362 Method* old_method = old_methods->at(i);
4363 if (old_method->is_obsolete()) {
4364 // only obsolete methods are interesting
4365 Symbol* m_name = old_method->name();
4366 Symbol* m_signature = old_method->signature();
4367
4368 // previous versions are linked together through the InstanceKlass
4369 int j = 0;
4370 for (InstanceKlass* prev_version = _previous_versions;
4371 prev_version != nullptr;
4372 prev_version = prev_version->previous_versions(), j++) {
4373
4374 Array<Method*>* method_refs = prev_version->methods();
4375 for (int k = 0; k < method_refs->length(); k++) {
4376 Method* method = method_refs->at(k);
4377
4378 if (!method->is_obsolete() &&
4379 method->name() == m_name &&
4380 method->signature() == m_signature) {
4381 // The current RedefineClasses() call has made all EMCP
4382 // versions of this method obsolete so mark it as obsolete
4383 log_trace(redefine, class, iklass, add)
4384 ("%s(%s): flush obsolete method @%d in version @%d",
4385 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4386
4387 method->set_is_obsolete();
4388 break;
4389 }
4390 }
4391
4392 // The previous loop may not find a matching EMCP method, but
4393 // that doesn't mean that we can optimize and not go any
4394 // further back in the PreviousVersion generations. The EMCP
4395 // method for this generation could have already been made obsolete,
4396 // but there still may be an older EMCP method that has not
4397 // been made obsolete.
4398 }
4399
4400 if (++local_count >= obsolete_method_count) {
4401 // no more obsolete methods so bail out now
4402 break;
4403 }
4404 }
4405 }
4406 }
4407 }
4408
4409 // Save the scratch_class as the previous version if any of the methods are running.
4410 // The previous_versions are used to set breakpoints in EMCP methods and they are
4411 // also used to clean MethodData links to redefined methods that are no longer running.
4412 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4413 int emcp_method_count) {
4414 assert(Thread::current()->is_VM_thread(),
4415 "only VMThread can add previous versions");
4416
4417 ResourceMark rm;
4418 log_trace(redefine, class, iklass, add)
4419 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4420
4421 // Clean out old previous versions for this class
4422 purge_previous_version_list();
4423
4424 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4425 // a previous redefinition may be made obsolete by this redefinition.
4426 Array<Method*>* old_methods = scratch_class->methods();
4427 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4428
4429 // If the constant pool for this previous version of the class
4430 // is not marked as being on the stack, then none of the methods
4431 // in this previous version of the class are on the stack so
4432 // we don't need to add this as a previous version.
4433 ConstantPool* cp_ref = scratch_class->constants();
4434 if (!cp_ref->on_stack()) {
4435 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4436 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4437 return;
4438 }
4439
4440 // Add previous version if any methods are still running or if this is
4441 // a shared class which should never be removed.
4442 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4443 scratch_class->link_previous_versions(previous_versions());
4444 link_previous_versions(scratch_class);
4445 if (cp_ref->is_shared()) {
4446 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4447 } else {
4448 // We only set clean_previous_versions flag for processing during class
4449 // unloading for non-shared classes.
4450 _should_clean_previous_versions = true;
4451 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4452 }
4453 } // end add_previous_version()
4454
4455 #endif // INCLUDE_JVMTI
4456
4457 Method* InstanceKlass::method_with_idnum(int idnum) {
4458 Method* m = nullptr;
4459 if (idnum < methods()->length()) {
4460 m = methods()->at(idnum);
4461 }
4462 if (m == nullptr || m->method_idnum() != idnum) {
4463 for (int index = 0; index < methods()->length(); ++index) {
4464 m = methods()->at(index);
4465 if (m->method_idnum() == idnum) {
4466 return m;
4467 }
4468 }
4469 // None found, return null for the caller to handle.
4470 return nullptr;
4471 }
4472 return m;
4473 }
4474
4475
4476 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4477 if (idnum >= methods()->length()) {
4478 return nullptr;
4479 }
4480 Method* m = methods()->at(idnum);
4481 if (m != nullptr && m->orig_method_idnum() == idnum) {
4482 return m;
4483 }
4484 // Obsolete method idnum does not match the original idnum
4485 for (int index = 0; index < methods()->length(); ++index) {
4486 m = methods()->at(index);
4487 if (m->orig_method_idnum() == idnum) {
4488 return m;
4489 }
4490 }
4491 // None found, return null for the caller to handle.
4492 return nullptr;
4493 }
4494
4495
4496 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4497 InstanceKlass* holder = get_klass_version(version);
4498 if (holder == nullptr) {
4499 return nullptr; // The version of klass is gone, no method is found
4500 }
4501 Method* method = holder->method_with_orig_idnum(idnum);
4502 return method;
4503 }
4504
4505 #if INCLUDE_JVMTI
4506 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4507 return _cached_class_file;
4508 }
4509
4510 jint InstanceKlass::get_cached_class_file_len() {
4511 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4512 }
4513
4514 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4515 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4516 }
4517 #endif
4518
4519 // Make a step iterating over the class hierarchy under the root class.
4520 // Skips subclasses if requested.
4521 void ClassHierarchyIterator::next() {
4522 assert(_current != nullptr, "required");
4523 if (_visit_subclasses && _current->subklass() != nullptr) {
4524 _current = _current->subklass();
4525 return; // visit next subclass
4526 }
4527 _visit_subclasses = true; // reset
4528 while (_current->next_sibling() == nullptr && _current != _root) {
4529 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4530 }
4531 if (_current == _root) {
4532 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4533 _current = nullptr;
4534 return;
4535 }
4536 _current = _current->next_sibling();
4537 return; // visit next sibling subclass
4538 }