1 /*
2 * Copyright (c) 1997, 2025, 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 "cds/aotClassInitializer.hpp"
26 #include "cds/aotMetaspace.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 "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeStream.hpp"
49 #include "interpreter/oopMapCache.hpp"
50 #include "interpreter/rewriter.hpp"
51 #include "jvm.h"
52 #include "jvmtifiles/jvmti.h"
53 #include "klass.inline.hpp"
54 #include "logging/log.hpp"
55 #include "logging/logMessage.hpp"
56 #include "logging/logStream.hpp"
57 #include "memory/allocation.inline.hpp"
58 #include "memory/iterator.inline.hpp"
59 #include "memory/metadataFactory.hpp"
60 #include "memory/metaspaceClosure.hpp"
61 #include "memory/oopFactory.hpp"
62 #include "memory/resourceArea.hpp"
63 #include "memory/universe.hpp"
64 #include "oops/constantPool.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/instanceClassLoaderKlass.hpp"
67 #include "oops/instanceKlass.inline.hpp"
68 #include "oops/instanceMirrorKlass.hpp"
69 #include "oops/instanceOop.hpp"
70 #include "oops/instanceStackChunkKlass.hpp"
71 #include "oops/klass.inline.hpp"
72 #include "oops/method.hpp"
73 #include "oops/oop.inline.hpp"
74 #include "oops/recordComponent.hpp"
75 #include "oops/symbol.hpp"
76 #include "prims/jvmtiExport.hpp"
77 #include "prims/jvmtiRedefineClasses.hpp"
78 #include "prims/jvmtiThreadState.hpp"
79 #include "prims/methodComparator.hpp"
80 #include "runtime/arguments.hpp"
81 #include "runtime/atomicAccess.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/fieldDescriptor.inline.hpp"
84 #include "runtime/handles.inline.hpp"
85 #include "runtime/javaCalls.hpp"
86 #include "runtime/javaThread.inline.hpp"
87 #include "runtime/mutexLocker.hpp"
88 #include "runtime/orderAccess.hpp"
89 #include "runtime/os.inline.hpp"
90 #include "runtime/reflection.hpp"
91 #include "runtime/synchronizer.hpp"
92 #include "runtime/threads.hpp"
93 #include "services/classLoadingService.hpp"
94 #include "services/finalizerService.hpp"
95 #include "services/threadService.hpp"
96 #include "utilities/dtrace.hpp"
97 #include "utilities/events.hpp"
98 #include "utilities/macros.hpp"
99 #include "utilities/nativeStackPrinter.hpp"
100 #include "utilities/stringUtils.hpp"
101 #ifdef COMPILER1
102 #include "c1/c1_Compiler.hpp"
103 #endif
104 #if INCLUDE_JFR
105 #include "jfr/jfrEvents.hpp"
106 #endif
107
108 #ifdef DTRACE_ENABLED
109
110
111 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
112 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
113 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
114 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
115 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
116 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
117 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
118 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
119 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
120 { \
121 char* data = nullptr; \
122 int len = 0; \
123 Symbol* clss_name = name(); \
124 if (clss_name != nullptr) { \
125 data = (char*)clss_name->bytes(); \
126 len = clss_name->utf8_length(); \
127 } \
128 HOTSPOT_CLASS_INITIALIZATION_##type( \
129 data, len, (void*)class_loader(), thread_type); \
130 }
131
132 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
133 { \
134 char* data = nullptr; \
135 int len = 0; \
136 Symbol* clss_name = name(); \
137 if (clss_name != nullptr) { \
138 data = (char*)clss_name->bytes(); \
139 len = clss_name->utf8_length(); \
140 } \
141 HOTSPOT_CLASS_INITIALIZATION_##type( \
142 data, len, (void*)class_loader(), thread_type, wait); \
143 }
144
145 #else // ndef DTRACE_ENABLED
146
147 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
148 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
149
150 #endif // ndef DTRACE_ENABLED
151
152 bool InstanceKlass::_finalization_enabled = true;
153
154 static inline bool is_class_loader(const Symbol* class_name,
155 const ClassFileParser& parser) {
156 assert(class_name != nullptr, "invariant");
157
158 if (class_name == vmSymbols::java_lang_ClassLoader()) {
159 return true;
160 }
161
162 if (vmClasses::ClassLoader_klass_is_loaded()) {
163 const Klass* const super_klass = parser.super_klass();
164 if (super_klass != nullptr) {
165 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
166 return true;
167 }
168 }
169 }
170 return false;
171 }
172
173 static inline bool is_stack_chunk_class(const Symbol* class_name,
174 const ClassLoaderData* loader_data) {
175 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
176 loader_data->is_the_null_class_loader_data());
177 }
178
179 // private: called to verify that k is a static member of this nest.
180 // We know that k is an instance class in the same package and hence the
181 // same classloader.
182 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
183 assert(!is_hidden(), "unexpected hidden class");
184 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
185 if (log_is_enabled(Trace, class, nestmates)) {
186 ResourceMark rm(current);
187 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
188 k->external_name(), this->external_name());
189 }
190 return false;
191 }
192
193 if (log_is_enabled(Trace, class, nestmates)) {
194 ResourceMark rm(current);
195 log_trace(class, nestmates)("Checking nest membership of %s in %s",
196 k->external_name(), this->external_name());
197 }
198
199 // Check for the named class in _nest_members.
200 // We don't resolve, or load, any classes.
201 for (int i = 0; i < _nest_members->length(); i++) {
202 int cp_index = _nest_members->at(i);
203 Symbol* name = _constants->klass_name_at(cp_index);
204 if (name == k->name()) {
205 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
206 return true;
207 }
208 }
209 log_trace(class, nestmates)("- class is NOT a nest member!");
210 return false;
211 }
212
213 // Called to verify that k is a permitted subclass of this class.
214 // The incoming stringStream is used to format the messages for error logging and for the caller
215 // to use for exception throwing.
216 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
217 Thread* current = Thread::current();
218 assert(k != nullptr, "sanity check");
219 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
220 "unexpected empty _permitted_subclasses array");
221
222 if (log_is_enabled(Trace, class, sealed)) {
223 ResourceMark rm(current);
224 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
225 k->external_name(), this->external_name());
226 }
227
228 // Check that the class and its super are in the same module.
229 if (k->module() != this->module()) {
230 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
231 "and sealed class %s is in module '%s' with loader %s",
232 k->external_name(),
233 k->module()->name_as_C_string(),
234 k->module()->loader_data()->loader_name_and_id(),
235 this->external_name(),
236 this->module()->name_as_C_string(),
237 this->module()->loader_data()->loader_name_and_id());
238 log_trace(class, sealed)(" - %s", ss.as_string());
239 return false;
240 }
241
242 if (!k->is_public() && !is_same_class_package(k)) {
243 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
244 "and sealed class %s is in package '%s' with classloader %s",
245 k->external_name(),
246 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
247 k->module()->loader_data()->loader_name_and_id(),
248 this->external_name(),
249 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
250 this->module()->loader_data()->loader_name_and_id());
251 log_trace(class, sealed)(" - %s", ss.as_string());
252 return false;
253 }
254
255 for (int i = 0; i < _permitted_subclasses->length(); i++) {
256 int cp_index = _permitted_subclasses->at(i);
257 Symbol* name = _constants->klass_name_at(cp_index);
258 if (name == k->name()) {
259 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
260 return true;
261 }
262 }
263
264 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
265 k->external_name(), this->external_name());
266 log_trace(class, sealed)(" - %s", ss.as_string());
267 return false;
268 }
269
270 // Return nest-host class, resolving, validating and saving it if needed.
271 // In cases where this is called from a thread that cannot do classloading
272 // (such as a native JIT thread) then we simply return null, which in turn
273 // causes the access check to return false. Such code will retry the access
274 // from a more suitable environment later. Otherwise the _nest_host is always
275 // set once this method returns.
276 // Any errors from nest-host resolution must be preserved so they can be queried
277 // from higher-level access checking code, and reported as part of access checking
278 // exceptions.
279 // VirtualMachineErrors are propagated with a null return.
280 // Under any conditions where the _nest_host can be set to non-null the resulting
281 // value of it and, if applicable, the nest host resolution/validation error,
282 // are idempotent.
283 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
284 InstanceKlass* nest_host_k = _nest_host;
285 if (nest_host_k != nullptr) {
286 return nest_host_k;
287 }
288
289 ResourceMark rm(THREAD);
290
291 // need to resolve and save our nest-host class.
292 if (_nest_host_index != 0) { // we have a real nest_host
293 // Before trying to resolve check if we're in a suitable context
294 bool can_resolve = THREAD->can_call_java();
295 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
296 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
297 this->external_name());
298 return nullptr; // sentinel to say "try again from a different context"
299 }
300
301 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
302 this->external_name(),
303 _constants->klass_name_at(_nest_host_index)->as_C_string());
304
305 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
306 if (HAS_PENDING_EXCEPTION) {
307 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
308 return nullptr; // propagate VMEs
309 }
310 stringStream ss;
311 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
312 ss.print("Nest host resolution of %s with host %s failed: ",
313 this->external_name(), target_host_class);
314 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
315 constantPoolHandle cph(THREAD, constants());
316 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
317 CLEAR_PENDING_EXCEPTION;
318
319 log_trace(class, nestmates)("%s", ss.base());
320 } else {
321 // A valid nest-host is an instance class in the current package that lists this
322 // class as a nest member. If any of these conditions are not met the class is
323 // its own nest-host.
324 const char* error = nullptr;
325
326 // JVMS 5.4.4 indicates package check comes first
327 if (is_same_class_package(k)) {
328 // Now check actual membership. We can't be a member if our "host" is
329 // not an instance class.
330 if (k->is_instance_klass()) {
331 nest_host_k = InstanceKlass::cast(k);
332 bool is_member = nest_host_k->has_nest_member(THREAD, this);
333 if (is_member) {
334 _nest_host = nest_host_k; // save resolved nest-host value
335
336 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
337 this->external_name(), k->external_name());
338 return nest_host_k;
339 } else {
340 error = "current type is not listed as a nest member";
341 }
342 } else {
343 error = "host is not an instance class";
344 }
345 } else {
346 error = "types are in different packages";
347 }
348
349 // something went wrong, so record what and log it
350 {
351 stringStream ss;
352 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
353 this->external_name(),
354 this->class_loader_data()->loader_name_and_id(),
355 k->external_name(),
356 k->class_loader_data()->loader_name_and_id(),
357 error);
358 constantPoolHandle cph(THREAD, constants());
359 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
360 log_trace(class, nestmates)("%s", ss.base());
361 }
362 }
363 } else {
364 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
365 this->external_name());
366 }
367
368 // Either not in an explicit nest, or else an error occurred, so
369 // the nest-host is set to `this`. Any thread that sees this assignment
370 // will also see any setting of nest_host_error(), if applicable.
371 return (_nest_host = this);
372 }
373
374 // Dynamic nest member support: set this class's nest host to the given class.
375 // This occurs as part of the class definition, as soon as the instanceKlass
376 // has been created and doesn't require further resolution. The code:
377 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
378 // results in:
379 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
380 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
381 // We also know the "host" is a valid nest-host in the same package so we can
382 // assert some of those facts.
383 void InstanceKlass::set_nest_host(InstanceKlass* host) {
384 assert(is_hidden(), "must be a hidden class");
385 assert(host != nullptr, "null nest host specified");
386 assert(_nest_host == nullptr, "current class has resolved nest-host");
387 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
388 nest_host_error());
389 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
390 (host->_nest_host == host), "proposed host is not a valid nest-host");
391 // Can't assert this as package is not set yet:
392 // assert(is_same_class_package(host), "proposed host is in wrong package");
393
394 if (log_is_enabled(Trace, class, nestmates)) {
395 ResourceMark rm;
396 const char* msg = "";
397 // a hidden class does not expect a statically defined nest-host
398 if (_nest_host_index > 0) {
399 msg = "(the NestHost attribute in the current class is ignored)";
400 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
401 msg = "(the NestMembers attribute in the current class is ignored)";
402 }
403 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
404 this->external_name(),
405 host->external_name(),
406 msg);
407 }
408 // set dynamic nest host
409 _nest_host = host;
410 // Record dependency to keep nest host from being unloaded before this class.
411 ClassLoaderData* this_key = class_loader_data();
412 assert(this_key != nullptr, "sanity");
413 this_key->record_dependency(host);
414 }
415
416 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
417 // or we are k's nest_host - all of which is covered by comparing the two
418 // resolved_nest_hosts.
419 // Any exceptions (i.e. VMEs) are propagated.
420 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
421
422 assert(this != k, "this should be handled by higher-level code");
423
424 // Per JVMS 5.4.4 we first resolve and validate the current class, then
425 // the target class k.
426
427 InstanceKlass* cur_host = nest_host(CHECK_false);
428 if (cur_host == nullptr) {
429 return false;
430 }
431
432 Klass* k_nest_host = k->nest_host(CHECK_false);
433 if (k_nest_host == nullptr) {
434 return false;
435 }
436
437 bool access = (cur_host == k_nest_host);
438
439 ResourceMark rm(THREAD);
440 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
441 this->external_name(),
442 access ? "" : "NOT ",
443 k->external_name());
444 return access;
445 }
446
447 const char* InstanceKlass::nest_host_error() {
448 if (_nest_host_index == 0) {
449 return nullptr;
450 } else {
451 constantPoolHandle cph(Thread::current(), constants());
452 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
453 }
454 }
455
456 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
457 const int size = InstanceKlass::size(parser.vtable_size(),
458 parser.itable_size(),
459 nonstatic_oop_map_size(parser.total_oop_map_count()),
460 parser.is_interface());
461
462 const Symbol* const class_name = parser.class_name();
463 assert(class_name != nullptr, "invariant");
464 ClassLoaderData* loader_data = parser.loader_data();
465 assert(loader_data != nullptr, "invariant");
466
467 InstanceKlass* ik;
468
469 // Allocation
470 if (parser.is_instance_ref_klass()) {
471 // java.lang.ref.Reference
472 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
473 } else if (class_name == vmSymbols::java_lang_Class()) {
474 // mirror - java.lang.Class
475 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
476 } else if (is_stack_chunk_class(class_name, loader_data)) {
477 // stack chunk
478 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
479 } else if (is_class_loader(class_name, parser)) {
480 // class loader - java.lang.ClassLoader
481 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
482 } else {
483 // normal
484 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
485 }
486
487 if (ik != nullptr && UseCompressedClassPointers) {
488 assert(CompressedKlassPointers::is_encodable(ik),
489 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
490 }
491
492 // Check for pending exception before adding to the loader data and incrementing
493 // class count. Can get OOM here.
494 if (HAS_PENDING_EXCEPTION) {
495 return nullptr;
496 }
497
498 return ik;
499 }
500
501
502 // copy method ordering from resource area to Metaspace
503 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
504 if (m != nullptr) {
505 // allocate a new array and copy contents (memcpy?)
506 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
507 for (int i = 0; i < m->length(); i++) {
508 _method_ordering->at_put(i, m->at(i));
509 }
510 } else {
511 _method_ordering = Universe::the_empty_int_array();
512 }
513 }
514
515 // create a new array of vtable_indices for default methods
516 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
517 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
518 assert(default_vtable_indices() == nullptr, "only create once");
519 set_default_vtable_indices(vtable_indices);
520 return vtable_indices;
521 }
522
523
524 InstanceKlass::InstanceKlass() {
525 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
526 }
527
528 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
529 Klass(kind),
530 _nest_members(nullptr),
531 _nest_host(nullptr),
532 _permitted_subclasses(nullptr),
533 _record_components(nullptr),
534 _static_field_size(parser.static_field_size()),
535 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
536 _itable_len(parser.itable_size()),
537 _nest_host_index(0),
538 _init_state(allocated),
539 _reference_type(reference_type),
540 _init_thread(nullptr)
541 {
542 set_vtable_length(parser.vtable_size());
543 set_access_flags(parser.access_flags());
544 if (parser.is_hidden()) set_is_hidden();
545 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
546 false));
547
548 assert(nullptr == _methods, "underlying memory not zeroed?");
549 assert(is_instance_klass(), "is layout incorrect?");
550 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
551 }
552
553 void InstanceKlass::set_is_cloneable() {
554 if (name() == vmSymbols::java_lang_invoke_MemberName()) {
555 assert(is_final(), "no subclasses allowed");
556 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
557 } else if (reference_type() != REF_NONE) {
558 // Reference cloning should not be intrinsified and always happen in JVM_Clone.
559 } else {
560 set_is_cloneable_fast();
561 }
562 }
563
564 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
565 Array<Method*>* methods) {
566 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
567 !methods->in_aot_cache()) {
568 for (int i = 0; i < methods->length(); i++) {
569 Method* method = methods->at(i);
570 if (method == nullptr) continue; // maybe null if error processing
571 // Only want to delete methods that are not executing for RedefineClasses.
572 // The previous version will point to them so they're not totally dangling
573 assert (!method->on_stack(), "shouldn't be called with methods on stack");
574 MetadataFactory::free_metadata(loader_data, method);
575 }
576 MetadataFactory::free_array<Method*>(loader_data, methods);
577 }
578 }
579
580 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
581 const InstanceKlass* super_klass,
582 Array<InstanceKlass*>* local_interfaces,
583 Array<InstanceKlass*>* transitive_interfaces) {
584 // Only deallocate transitive interfaces if not empty, same as super class
585 // or same as local interfaces. See code in parseClassFile.
586 Array<InstanceKlass*>* ti = transitive_interfaces;
587 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
588 // check that the interfaces don't come from super class
589 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
590 super_klass->transitive_interfaces();
591 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
592 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
593 }
594 }
595
596 // local interfaces can be empty
597 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
598 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
599 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
600 }
601 }
602
603 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
604 Array<RecordComponent*>* record_components) {
605 if (record_components != nullptr && !record_components->in_aot_cache()) {
606 for (int i = 0; i < record_components->length(); i++) {
607 RecordComponent* record_component = record_components->at(i);
608 MetadataFactory::free_metadata(loader_data, record_component);
609 }
610 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
611 }
612 }
613
614 // This function deallocates the metadata and C heap pointers that the
615 // InstanceKlass points to.
616 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
617 // Orphan the mirror first, CMS thinks it's still live.
618 if (java_mirror() != nullptr) {
619 java_lang_Class::set_klass(java_mirror(), nullptr);
620 }
621
622 // Also remove mirror from handles
623 loader_data->remove_handle(_java_mirror);
624
625 // Need to take this class off the class loader data list.
626 loader_data->remove_class(this);
627
628 // The array_klass for this class is created later, after error handling.
629 // For class redefinition, we keep the original class so this scratch class
630 // doesn't have an array class. Either way, assert that there is nothing
631 // to deallocate.
632 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
633
634 // Release C heap allocated data that this points to, which includes
635 // reference counting symbol names.
636 // Can't release the constant pool or MethodData C heap data here because the constant
637 // pool can be deallocated separately from the InstanceKlass for default methods and
638 // redefine classes. MethodData can also be released separately.
639 release_C_heap_structures(/* release_sub_metadata */ false);
640
641 deallocate_methods(loader_data, methods());
642 set_methods(nullptr);
643
644 deallocate_record_components(loader_data, record_components());
645 set_record_components(nullptr);
646
647 if (method_ordering() != nullptr &&
648 method_ordering() != Universe::the_empty_int_array() &&
649 !method_ordering()->in_aot_cache()) {
650 MetadataFactory::free_array<int>(loader_data, method_ordering());
651 }
652 set_method_ordering(nullptr);
653
654 // default methods can be empty
655 if (default_methods() != nullptr &&
656 default_methods() != Universe::the_empty_method_array() &&
657 !default_methods()->in_aot_cache()) {
658 MetadataFactory::free_array<Method*>(loader_data, default_methods());
659 }
660 // Do NOT deallocate the default methods, they are owned by superinterfaces.
661 set_default_methods(nullptr);
662
663 // default methods vtable indices can be empty
664 if (default_vtable_indices() != nullptr &&
665 !default_vtable_indices()->in_aot_cache()) {
666 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
667 }
668 set_default_vtable_indices(nullptr);
669
670
671 // This array is in Klass, but remove it with the InstanceKlass since
672 // this place would be the only caller and it can share memory with transitive
673 // interfaces.
674 if (secondary_supers() != nullptr &&
675 secondary_supers() != Universe::the_empty_klass_array() &&
676 // see comments in compute_secondary_supers about the following cast
677 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
678 !secondary_supers()->in_aot_cache()) {
679 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
680 }
681 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
682
683 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
684 set_transitive_interfaces(nullptr);
685 set_local_interfaces(nullptr);
686
687 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
688 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
689 }
690 set_fieldinfo_stream(nullptr);
691
692 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
693 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
694 }
695 set_fieldinfo_search_table(nullptr);
696
697 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
698 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
699 }
700 set_fields_status(nullptr);
701
702 // If a method from a redefined class is using this constant pool, don't
703 // delete it, yet. The new class's previous version will point to this.
704 if (constants() != nullptr) {
705 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
706 if (!constants()->in_aot_cache()) {
707 MetadataFactory::free_metadata(loader_data, constants());
708 }
709 // Delete any cached resolution errors for the constant pool
710 SystemDictionary::delete_resolution_error(constants());
711
712 set_constants(nullptr);
713 }
714
715 if (inner_classes() != nullptr &&
716 inner_classes() != Universe::the_empty_short_array() &&
717 !inner_classes()->in_aot_cache()) {
718 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
719 }
720 set_inner_classes(nullptr);
721
722 if (nest_members() != nullptr &&
723 nest_members() != Universe::the_empty_short_array() &&
724 !nest_members()->in_aot_cache()) {
725 MetadataFactory::free_array<jushort>(loader_data, nest_members());
726 }
727 set_nest_members(nullptr);
728
729 if (permitted_subclasses() != nullptr &&
730 permitted_subclasses() != Universe::the_empty_short_array() &&
731 !permitted_subclasses()->in_aot_cache()) {
732 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
733 }
734 set_permitted_subclasses(nullptr);
735
736 // We should deallocate the Annotations instance if it's not in shared spaces.
737 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
738 MetadataFactory::free_metadata(loader_data, annotations());
739 }
740 set_annotations(nullptr);
741
742 SystemDictionaryShared::handle_class_unloading(this);
743
744 #if INCLUDE_CDS_JAVA_HEAP
745 if (CDSConfig::is_dumping_heap()) {
746 HeapShared::remove_scratch_objects(this);
747 }
748 #endif
749 }
750
751 bool InstanceKlass::is_record() const {
752 return _record_components != nullptr &&
753 is_final() &&
754 super() == vmClasses::Record_klass();
755 }
756
757 bool InstanceKlass::is_sealed() const {
758 return _permitted_subclasses != nullptr &&
759 _permitted_subclasses != Universe::the_empty_short_array();
760 }
761
762 // JLS 8.9: An enum class is either implicitly final and derives
763 // from java.lang.Enum, or else is implicitly sealed to its
764 // anonymous subclasses. This query detects both kinds.
765 // It does not validate the finality or
766 // sealing conditions: it merely checks for a super of Enum.
767 // This is sufficient for recognizing well-formed enums.
768 bool InstanceKlass::is_enum_subclass() const {
769 InstanceKlass* s = super();
770 return (s == vmClasses::Enum_klass() ||
771 (s != nullptr && s->super() == vmClasses::Enum_klass()));
772 }
773
774 bool InstanceKlass::should_be_initialized() const {
775 return !is_initialized();
776 }
777
778 klassItable InstanceKlass::itable() const {
779 return klassItable(const_cast<InstanceKlass*>(this));
780 }
781
782 // JVMTI spec thinks there are signers and protection domain in the
783 // instanceKlass. These accessors pretend these fields are there.
784 // The hprof specification also thinks these fields are in InstanceKlass.
785 oop InstanceKlass::protection_domain() const {
786 // return the protection_domain from the mirror
787 return java_lang_Class::protection_domain(java_mirror());
788 }
789
790 objArrayOop InstanceKlass::signers() const {
791 // return the signers from the mirror
792 return java_lang_Class::signers(java_mirror());
793 }
794
795 oop InstanceKlass::init_lock() const {
796 // return the init lock from the mirror
797 oop lock = java_lang_Class::init_lock(java_mirror());
798 // Prevent reordering with any access of initialization state
799 OrderAccess::loadload();
800 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
801 "only fully initialized state can have a null lock");
802 return lock;
803 }
804
805 // Set the initialization lock to null so the object can be GC'ed. Any racing
806 // threads to get this lock will see a null lock and will not lock.
807 // That's okay because they all check for initialized state after getting
808 // the lock and return. For preempted vthreads we keep the oop protected
809 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()).
810 void InstanceKlass::fence_and_clear_init_lock() {
811 // make sure previous stores are all done, notably the init_state.
812 OrderAccess::storestore();
813 java_lang_Class::clear_init_lock(java_mirror());
814 assert(!is_not_initialized(), "class must be initialized now");
815 }
816
817 class PreemptableInitCall {
818 JavaThread* _thread;
819 bool _previous;
820 DEBUG_ONLY(InstanceKlass* _previous_klass;)
821 public:
822 PreemptableInitCall(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
823 _previous = thread->at_preemptable_init();
824 _thread->set_at_preemptable_init(true);
825 DEBUG_ONLY(_previous_klass = _thread->preempt_init_klass();)
826 DEBUG_ONLY(_thread->set_preempt_init_klass(ik));
827 }
828 ~PreemptableInitCall() {
829 _thread->set_at_preemptable_init(_previous);
830 DEBUG_ONLY(_thread->set_preempt_init_klass(_previous_klass));
831 }
832 };
833
834 void InstanceKlass::initialize_preemptable(TRAPS) {
835 if (this->should_be_initialized()) {
836 PreemptableInitCall pic(THREAD, this);
837 initialize_impl(THREAD);
838 } else {
839 assert(is_initialized(), "sanity check");
840 }
841 }
842
843 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
844 // process. The step comments refers to the procedure described in that section.
845 // Note: implementation moved to static method to expose the this pointer.
846 void InstanceKlass::initialize(TRAPS) {
847 if (this->should_be_initialized()) {
848 initialize_impl(CHECK);
849 // Note: at this point the class may be initialized
850 // OR it may be in the state of being initialized
851 // in case of recursive initialization!
852 } else {
853 assert(is_initialized(), "sanity check");
854 }
855 }
856
857 #ifdef ASSERT
858 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
859 assert(has_aot_initialized_mirror(), "must be");
860
861 InstanceKlass* s = super();
862 if (s != nullptr) {
863 DEBUG_ONLY(ResourceMark rm);
864 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
865 s->external_name(), external_name());
866 s->assert_no_clinit_will_run_for_aot_initialized_class();
867 }
868
869 Array<InstanceKlass*>* interfaces = local_interfaces();
870 int len = interfaces->length();
871 for (int i = 0; i < len; i++) {
872 InstanceKlass* intf = interfaces->at(i);
873 if (!intf->is_initialized()) {
874 ResourceMark rm;
875 // Note: an interface needs to be marked as is_initialized() only if
876 // - it has a <clinit>
877 // - it has declared a default method.
878 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
879 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
880 intf->external_name(), external_name());
881 }
882 }
883 }
884 #endif
885
886 #if INCLUDE_CDS
887 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
888 assert(has_aot_initialized_mirror(), "must be");
889 assert(CDSConfig::is_loading_heap(), "must be");
890 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
891 assert_no_clinit_will_run_for_aot_initialized_class();
892
893 if (is_initialized()) {
894 return;
895 }
896
897 if (is_runtime_setup_required()) {
898 // Need to take the slow path, which will call the runtimeSetup() function instead
899 // of <clinit>
900 initialize(CHECK);
901 return;
902 }
903 if (log_is_enabled(Info, aot, init)) {
904 ResourceMark rm;
905 log_info(aot, init)("%s (aot-inited)", external_name());
906 }
907
908 link_class(CHECK);
909
910 #ifdef ASSERT
911 {
912 Handle h_init_lock(THREAD, init_lock());
913 ObjectLocker ol(h_init_lock, THREAD);
914 assert(!is_initialized(), "sanity");
915 assert(!is_being_initialized(), "sanity");
916 assert(!is_in_error_state(), "sanity");
917 }
918 #endif
919
920 set_init_thread(THREAD);
921 set_initialization_state_and_notify(fully_initialized, CHECK);
922 }
923 #endif
924
925 bool InstanceKlass::verify_code(TRAPS) {
926 // 1) Verify the bytecodes
927 return Verifier::verify(this, should_verify_class(), THREAD);
928 }
929
930 void InstanceKlass::link_class(TRAPS) {
931 assert(is_loaded(), "must be loaded");
932 if (!is_linked()) {
933 link_class_impl(CHECK);
934 }
935 }
936
937 // Called to verify that a class can link during initialization, without
938 // throwing a VerifyError.
939 bool InstanceKlass::link_class_or_fail(TRAPS) {
940 assert(is_loaded(), "must be loaded");
941 if (!is_linked()) {
942 link_class_impl(CHECK_false);
943 }
944 return is_linked();
945 }
946
947 bool InstanceKlass::link_class_impl(TRAPS) {
948 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
949 // This is for CDS static dump only -- we use the in_error_state to indicate that
950 // the class has failed verification. Throwing the NoClassDefFoundError here is just
951 // a convenient way to stop repeat attempts to verify the same (bad) class.
952 //
953 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
954 // if we are executing Java code. This is not a problem for CDS dumping phase since
955 // it doesn't execute any Java code.
956 ResourceMark rm(THREAD);
957 // Names are all known to be < 64k so we know this formatted message is not excessively large.
958 Exceptions::fthrow(THREAD_AND_LOCATION,
959 vmSymbols::java_lang_NoClassDefFoundError(),
960 "Class %s, or one of its supertypes, failed class initialization",
961 external_name());
962 return false;
963 }
964 // return if already verified
965 if (is_linked()) {
966 return true;
967 }
968
969 // Timing
970 // timer handles recursion
971 JavaThread* jt = THREAD;
972
973 // link super class before linking this class
974 InstanceKlass* super_klass = super();
975 if (super_klass != nullptr) {
976 if (super_klass->is_interface()) { // check if super class is an interface
977 ResourceMark rm(THREAD);
978 // Names are all known to be < 64k so we know this formatted message is not excessively large.
979 Exceptions::fthrow(
980 THREAD_AND_LOCATION,
981 vmSymbols::java_lang_IncompatibleClassChangeError(),
982 "class %s has interface %s as super class",
983 external_name(),
984 super_klass->external_name()
985 );
986 return false;
987 }
988
989 super_klass->link_class_impl(CHECK_false);
990 }
991
992 // link all interfaces implemented by this class before linking this class
993 Array<InstanceKlass*>* interfaces = local_interfaces();
994 int num_interfaces = interfaces->length();
995 for (int index = 0; index < num_interfaces; index++) {
996 InstanceKlass* interk = interfaces->at(index);
997 interk->link_class_impl(CHECK_false);
998 }
999
1000 // in case the class is linked in the process of linking its superclasses
1001 if (is_linked()) {
1002 return true;
1003 }
1004
1005 // trace only the link time for this klass that includes
1006 // the verification time
1007 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1008 ClassLoader::perf_class_link_selftime(),
1009 ClassLoader::perf_classes_linked(),
1010 jt->get_thread_stat()->perf_recursion_counts_addr(),
1011 jt->get_thread_stat()->perf_timers_addr(),
1012 PerfClassTraceTime::CLASS_LINK);
1013
1014 // verification & rewriting
1015 {
1016 HandleMark hm(THREAD);
1017 Handle h_init_lock(THREAD, init_lock());
1018 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false);
1019 // Don't allow preemption if we link/initialize classes below,
1020 // since that would release this monitor while we are in the
1021 // middle of linking this class.
1022 NoPreemptMark npm(THREAD);
1023
1024 // rewritten will have been set if loader constraint error found
1025 // on an earlier link attempt
1026 // don't verify or rewrite if already rewritten
1027 //
1028
1029 if (!is_linked()) {
1030 if (!is_rewritten()) {
1031 if (in_aot_cache()) {
1032 assert(!verified_at_dump_time(), "must be");
1033 }
1034 {
1035 bool verify_ok = verify_code(THREAD);
1036 if (!verify_ok) {
1037 return false;
1038 }
1039 }
1040
1041 // Just in case a side-effect of verify linked this class already
1042 // (which can sometimes happen since the verifier loads classes
1043 // using custom class loaders, which are free to initialize things)
1044 if (is_linked()) {
1045 return true;
1046 }
1047
1048 // also sets rewritten
1049 rewrite_class(CHECK_false);
1050 } else if (in_aot_cache()) {
1051 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1052 }
1053
1054 // relocate jsrs and link methods after they are all rewritten
1055 link_methods(CHECK_false);
1056
1057 // Initialize the vtable and interface table after
1058 // methods have been rewritten since rewrite may
1059 // fabricate new Method*s.
1060 // also does loader constraint checking
1061 //
1062 // initialize_vtable and initialize_itable need to be rerun
1063 // for a shared class if
1064 // 1) the class is loaded by custom class loader or
1065 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1066 // 3) the class was not verified during dump time
1067 bool need_init_table = true;
1068 if (in_aot_cache() && verified_at_dump_time() &&
1069 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1070 need_init_table = false;
1071 }
1072 if (need_init_table) {
1073 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1074 itable().initialize_itable_and_check_constraints(CHECK_false);
1075 }
1076 #ifdef ASSERT
1077 vtable().verify(tty, true);
1078 // In case itable verification is ever added.
1079 // itable().verify(tty, true);
1080 #endif
1081 if (Universe::is_fully_initialized()) {
1082 DeoptimizationScope deopt_scope;
1083 {
1084 // Now mark all code that assumes the class is not linked.
1085 // Set state under the Compile_lock also.
1086 MutexLocker ml(THREAD, Compile_lock);
1087
1088 set_init_state(linked);
1089 CodeCache::mark_dependents_on(&deopt_scope, this);
1090 }
1091 // Perform the deopt handshake outside Compile_lock.
1092 deopt_scope.deoptimize_marked();
1093 } else {
1094 set_init_state(linked);
1095 }
1096 if (JvmtiExport::should_post_class_prepare()) {
1097 JvmtiExport::post_class_prepare(THREAD, this);
1098 }
1099 }
1100 }
1101 return true;
1102 }
1103
1104 // Rewrite the byte codes of all of the methods of a class.
1105 // The rewriter must be called exactly once. Rewriting must happen after
1106 // verification but before the first method of the class is executed.
1107 void InstanceKlass::rewrite_class(TRAPS) {
1108 assert(is_loaded(), "must be loaded");
1109 if (is_rewritten()) {
1110 assert(in_aot_cache(), "rewriting an unshared class?");
1111 return;
1112 }
1113 Rewriter::rewrite(this, CHECK);
1114 set_rewritten();
1115 }
1116
1117 // Now relocate and link method entry points after class is rewritten.
1118 // This is outside is_rewritten flag. In case of an exception, it can be
1119 // executed more than once.
1120 void InstanceKlass::link_methods(TRAPS) {
1121 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1122
1123 int len = methods()->length();
1124 for (int i = len-1; i >= 0; i--) {
1125 methodHandle m(THREAD, methods()->at(i));
1126
1127 // Set up method entry points for compiler and interpreter .
1128 m->link_method(m, CHECK);
1129 }
1130 }
1131
1132 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1133 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1134 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1135 for (int i = 0; i < local_interfaces()->length(); ++i) {
1136 InstanceKlass* ik = local_interfaces()->at(i);
1137
1138 // Initialization is depth first search ie. we start with top of the inheritance tree
1139 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1140 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1141 if (ik->has_nonstatic_concrete_methods()) {
1142 ik->initialize_super_interfaces(CHECK);
1143 }
1144
1145 // Only initialize() interfaces that "declare" concrete methods.
1146 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1147 ik->initialize(CHECK);
1148 }
1149 }
1150 }
1151
1152 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1153 static InitializationErrorTable* _initialization_error_table;
1154
1155 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1156 // Create the same exception with a message indicating the thread name,
1157 // and the StackTraceElements.
1158 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1159 ResourceMark rm(current);
1160 if (init_error.is_null()) {
1161 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1162
1163 // We failed to create the new exception, most likely due to either out-of-memory or
1164 // a stackoverflow error. If the original exception was either of those then we save
1165 // the shared, pre-allocated, stackless, instance of that exception.
1166 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1167 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1168 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1169 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1170 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1171 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1172 } else {
1173 return;
1174 }
1175 }
1176
1177 MutexLocker ml(current, ClassInitError_lock);
1178 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1179 bool created;
1180 if (_initialization_error_table == nullptr) {
1181 _initialization_error_table = new (mtClass) InitializationErrorTable();
1182 }
1183 _initialization_error_table->put_if_absent(this, elem, &created);
1184 assert(created, "Initialization is single threaded");
1185 log_trace(class, init)("Initialization error added for class %s", external_name());
1186 }
1187
1188 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1189 MutexLocker ml(current, ClassInitError_lock);
1190 if (_initialization_error_table == nullptr) {
1191 return nullptr;
1192 }
1193 OopHandle* h = _initialization_error_table->get(this);
1194 return (h != nullptr) ? h->resolve() : nullptr;
1195 }
1196
1197 // Need to remove entries for unloaded classes.
1198 void InstanceKlass::clean_initialization_error_table() {
1199 struct InitErrorTableCleaner {
1200 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1201 if (!ik->is_loader_alive()) {
1202 h.release(Universe::vm_global());
1203 return true;
1204 } else {
1205 return false;
1206 }
1207 }
1208 };
1209
1210 assert_locked_or_safepoint(ClassInitError_lock);
1211 InitErrorTableCleaner cleaner;
1212 if (_initialization_error_table != nullptr) {
1213 _initialization_error_table->unlink(&cleaner);
1214 }
1215 }
1216
1217 class ThreadWaitingForClassInit : public StackObj {
1218 JavaThread* _thread;
1219 public:
1220 ThreadWaitingForClassInit(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
1221 _thread->set_class_to_be_initialized(ik);
1222 }
1223 ~ThreadWaitingForClassInit() {
1224 _thread->set_class_to_be_initialized(nullptr);
1225 }
1226 };
1227
1228 void InstanceKlass::initialize_impl(TRAPS) {
1229 HandleMark hm(THREAD);
1230
1231 // Make sure klass is linked (verified) before initialization
1232 // A class could already be verified, since it has been reflected upon.
1233 link_class(CHECK);
1234
1235 DTRACE_CLASSINIT_PROBE(required, -1);
1236
1237 bool wait = false;
1238
1239 JavaThread* jt = THREAD;
1240
1241 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1242
1243 // refer to the JVM book page 47 for description of steps
1244 // Step 1
1245 {
1246 Handle h_init_lock(THREAD, init_lock());
1247 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE);
1248
1249 // Step 2
1250 // If we were to use wait() instead of waitInterruptibly() then
1251 // we might end up throwing IE from link/symbol resolution sites
1252 // that aren't expected to throw. This would wreak havoc. See 6320309.
1253 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1254 if (debug_logging_enabled) {
1255 ResourceMark rm(jt);
1256 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1257 jt->name(), external_name(), init_thread_name());
1258 }
1259 wait = true;
1260 ThreadWaitingForClassInit twcl(THREAD, this);
1261 ol.wait_uninterruptibly(CHECK_PREEMPTABLE);
1262 }
1263
1264 // Step 3
1265 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1266 if (debug_logging_enabled) {
1267 ResourceMark rm(jt);
1268 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1269 jt->name(), external_name());
1270 }
1271 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1272 return;
1273 }
1274
1275 // Step 4
1276 if (is_initialized()) {
1277 if (debug_logging_enabled) {
1278 ResourceMark rm(jt);
1279 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1280 jt->name(), external_name());
1281 }
1282 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1283 return;
1284 }
1285
1286 // Step 5
1287 if (is_in_error_state()) {
1288 if (debug_logging_enabled) {
1289 ResourceMark rm(jt);
1290 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1291 jt->name(), external_name());
1292 }
1293
1294 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1295 ResourceMark rm(THREAD);
1296 Handle cause(THREAD, get_initialization_error(THREAD));
1297
1298 stringStream ss;
1299 ss.print("Could not initialize class %s", external_name());
1300 if (cause.is_null()) {
1301 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1302 } else {
1303 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1304 ss.as_string(), cause);
1305 }
1306 } else {
1307
1308 // Step 6
1309 set_init_state(being_initialized);
1310 set_init_thread(jt);
1311 if (debug_logging_enabled) {
1312 ResourceMark rm(jt);
1313 log_debug(class, init)("Thread \"%s\" is initializing %s",
1314 jt->name(), external_name());
1315 }
1316 }
1317 }
1318
1319 // Block preemption once we are the initializer thread. Unmounting now
1320 // would complicate the reentrant case (identity is platform thread).
1321 NoPreemptMark npm(THREAD);
1322
1323 // Step 7
1324 // Next, if C is a class rather than an interface, initialize it's super class and super
1325 // interfaces.
1326 if (!is_interface()) {
1327 Klass* super_klass = super();
1328 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1329 super_klass->initialize(THREAD);
1330 }
1331 // If C implements any interface that declares a non-static, concrete method,
1332 // the initialization of C triggers initialization of its super interfaces.
1333 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1334 // having a superinterface that declares, non-static, concrete methods
1335 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1336 initialize_super_interfaces(THREAD);
1337 }
1338
1339 // If any exceptions, complete abruptly, throwing the same exception as above.
1340 if (HAS_PENDING_EXCEPTION) {
1341 Handle e(THREAD, PENDING_EXCEPTION);
1342 CLEAR_PENDING_EXCEPTION;
1343 {
1344 EXCEPTION_MARK;
1345 add_initialization_error(THREAD, e);
1346 // Locks object, set state, and notify all waiting threads
1347 set_initialization_state_and_notify(initialization_error, THREAD);
1348 CLEAR_PENDING_EXCEPTION;
1349 }
1350 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1351 THROW_OOP(e());
1352 }
1353 }
1354
1355
1356 // Step 8
1357 {
1358 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1359 if (class_initializer() != nullptr) {
1360 // Timer includes any side effects of class initialization (resolution,
1361 // etc), but not recursive entry into call_class_initializer().
1362 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1363 ClassLoader::perf_class_init_selftime(),
1364 ClassLoader::perf_classes_inited(),
1365 jt->get_thread_stat()->perf_recursion_counts_addr(),
1366 jt->get_thread_stat()->perf_timers_addr(),
1367 PerfClassTraceTime::CLASS_CLINIT);
1368 call_class_initializer(THREAD);
1369 } else {
1370 // The elapsed time is so small it's not worth counting.
1371 if (UsePerfData) {
1372 ClassLoader::perf_classes_inited()->inc();
1373 }
1374 call_class_initializer(THREAD);
1375 }
1376 }
1377
1378 // Step 9
1379 if (!HAS_PENDING_EXCEPTION) {
1380 set_initialization_state_and_notify(fully_initialized, CHECK);
1381 DEBUG_ONLY(vtable().verify(tty, true);)
1382 CompilationPolicy::replay_training_at_init(this, THREAD);
1383 }
1384 else {
1385 // Step 10 and 11
1386 Handle e(THREAD, PENDING_EXCEPTION);
1387 CLEAR_PENDING_EXCEPTION;
1388 // JVMTI has already reported the pending exception
1389 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1390 JvmtiExport::clear_detected_exception(jt);
1391 {
1392 EXCEPTION_MARK;
1393 add_initialization_error(THREAD, e);
1394 set_initialization_state_and_notify(initialization_error, THREAD);
1395 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1396 // JVMTI has already reported the pending exception
1397 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1398 JvmtiExport::clear_detected_exception(jt);
1399 }
1400 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1401 if (e->is_a(vmClasses::Error_klass())) {
1402 THROW_OOP(e());
1403 } else {
1404 JavaCallArguments args(e);
1405 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1406 vmSymbols::throwable_void_signature(),
1407 &args);
1408 }
1409 }
1410 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1411 }
1412
1413
1414 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1415 Handle h_init_lock(THREAD, init_lock());
1416 if (h_init_lock() != nullptr) {
1417 ObjectLocker ol(h_init_lock, THREAD);
1418 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1419 set_init_state(state);
1420 fence_and_clear_init_lock();
1421 ol.notify_all(CHECK);
1422 } else {
1423 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1424 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1425 set_init_state(state);
1426 }
1427 }
1428
1429 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1430 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1431 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1432 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1433
1434 DeoptimizationScope deopt_scope;
1435 {
1436 MutexLocker ml(current, Compile_lock);
1437
1438 set_init_state(InstanceKlass::loaded);
1439 // make sure init_state store is already done.
1440 // The compiler reads the hierarchy outside of the Compile_lock.
1441 // Access ordering is used to add to hierarchy.
1442
1443 // Link into hierarchy.
1444 append_to_sibling_list(); // add to superklass/sibling list
1445 process_interfaces(); // handle all "implements" declarations
1446
1447 // Now mark all code that depended on old class hierarchy.
1448 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1449 if (Universe::is_fully_initialized()) {
1450 CodeCache::mark_dependents_on(&deopt_scope, this);
1451 }
1452 }
1453 // Perform the deopt handshake outside Compile_lock.
1454 deopt_scope.deoptimize_marked();
1455 }
1456
1457
1458 InstanceKlass* InstanceKlass::implementor() const {
1459 InstanceKlass* volatile* ik = adr_implementor();
1460 if (ik == nullptr) {
1461 return nullptr;
1462 } else {
1463 // This load races with inserts, and therefore needs acquire.
1464 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1465 if (ikls != nullptr && !ikls->is_loader_alive()) {
1466 return nullptr; // don't return unloaded class
1467 } else {
1468 return ikls;
1469 }
1470 }
1471 }
1472
1473
1474 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1475 assert_locked_or_safepoint(Compile_lock);
1476 assert(is_interface(), "not interface");
1477 InstanceKlass* volatile* addr = adr_implementor();
1478 assert(addr != nullptr, "null addr");
1479 if (addr != nullptr) {
1480 AtomicAccess::release_store(addr, ik);
1481 }
1482 }
1483
1484 int InstanceKlass::nof_implementors() const {
1485 InstanceKlass* ik = implementor();
1486 if (ik == nullptr) {
1487 return 0;
1488 } else if (ik != this) {
1489 return 1;
1490 } else {
1491 return 2;
1492 }
1493 }
1494
1495 // The embedded _implementor field can only record one implementor.
1496 // When there are more than one implementors, the _implementor field
1497 // is set to the interface Klass* itself. Following are the possible
1498 // values for the _implementor field:
1499 // null - no implementor
1500 // implementor Klass* - one implementor
1501 // self - more than one implementor
1502 //
1503 // The _implementor field only exists for interfaces.
1504 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1505 if (Universe::is_fully_initialized()) {
1506 assert_lock_strong(Compile_lock);
1507 }
1508 assert(is_interface(), "not interface");
1509 // Filter out my subinterfaces.
1510 // (Note: Interfaces are never on the subklass list.)
1511 if (ik->is_interface()) return;
1512
1513 // Filter out subclasses whose supers already implement me.
1514 // (Note: CHA must walk subclasses of direct implementors
1515 // in order to locate indirect implementors.)
1516 InstanceKlass* super_ik = ik->super();
1517 if (super_ik != nullptr && super_ik->implements_interface(this))
1518 // We only need to check one immediate superclass, since the
1519 // implements_interface query looks at transitive_interfaces.
1520 // Any supers of the super have the same (or fewer) transitive_interfaces.
1521 return;
1522
1523 InstanceKlass* iklass = implementor();
1524 if (iklass == nullptr) {
1525 set_implementor(ik);
1526 } else if (iklass != this && iklass != ik) {
1527 // There is already an implementor. Use itself as an indicator of
1528 // more than one implementors.
1529 set_implementor(this);
1530 }
1531
1532 // The implementor also implements the transitive_interfaces
1533 for (int index = 0; index < local_interfaces()->length(); index++) {
1534 local_interfaces()->at(index)->add_implementor(ik);
1535 }
1536 }
1537
1538 void InstanceKlass::init_implementor() {
1539 if (is_interface()) {
1540 set_implementor(nullptr);
1541 }
1542 }
1543
1544
1545 void InstanceKlass::process_interfaces() {
1546 // link this class into the implementors list of every interface it implements
1547 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1548 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1549 InstanceKlass* interf = local_interfaces()->at(i);
1550 assert(interf->is_interface(), "expected interface");
1551 interf->add_implementor(this);
1552 }
1553 }
1554
1555 bool InstanceKlass::can_be_primary_super_slow() const {
1556 if (is_interface())
1557 return false;
1558 else
1559 return Klass::can_be_primary_super_slow();
1560 }
1561
1562 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1563 Array<InstanceKlass*>* transitive_interfaces) {
1564 // The secondaries are the implemented interfaces.
1565 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1566 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1567 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1568 int num_secondaries = num_extra_slots + interfaces->length();
1569 if (num_secondaries == 0) {
1570 // Must share this for correct bootstrapping!
1571 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1572 return nullptr;
1573 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1574 // We will reuse the transitive interfaces list if we're certain
1575 // it's in hash order.
1576 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1577 set_secondary_supers(interfaces, bitmap);
1578 return nullptr;
1579 }
1580 // Copy transitive interfaces to a temporary growable array to be constructed
1581 // into the secondary super list with extra slots.
1582 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1583 for (int i = 0; i < interfaces->length(); i++) {
1584 secondaries->push(interfaces->at(i));
1585 }
1586 return secondaries;
1587 }
1588
1589 bool InstanceKlass::implements_interface(Klass* k) const {
1590 if (this == k) return true;
1591 assert(k->is_interface(), "should be an interface class");
1592 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1593 if (transitive_interfaces()->at(i) == k) {
1594 return true;
1595 }
1596 }
1597 return false;
1598 }
1599
1600 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1601 // Verify direct super interface
1602 if (this == k) return true;
1603 assert(k->is_interface(), "should be an interface class");
1604 for (int i = 0; i < local_interfaces()->length(); i++) {
1605 if (local_interfaces()->at(i) == k) {
1606 return true;
1607 }
1608 }
1609 return false;
1610 }
1611
1612 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1613 if (TraceFinalizerRegistration) {
1614 tty->print("Registered ");
1615 i->print_value_on(tty);
1616 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1617 }
1618 instanceHandle h_i(THREAD, i);
1619 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1620 JavaValue result(T_VOID);
1621 JavaCallArguments args(h_i);
1622 methodHandle mh(THREAD, Universe::finalizer_register_method());
1623 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1624 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1625 return h_i();
1626 }
1627
1628 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1629 assert(!is_abstract() && !is_interface(), "Should not create this object");
1630 size_t size = size_helper(); // Query before forming handle.
1631 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1632 }
1633
1634 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1635 Klass* k = java_lang_Class::as_Klass(java_class);
1636 if (k == nullptr) {
1637 ResourceMark rm(THREAD);
1638 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1639 }
1640 InstanceKlass* ik = cast(k);
1641 ik->check_valid_for_instantiation(false, CHECK_NULL);
1642 ik->initialize(CHECK_NULL);
1643 return ik->allocate_instance(THREAD);
1644 }
1645
1646 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1647 return instanceHandle(THREAD, allocate_instance(THREAD));
1648 }
1649
1650 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1651 if (is_interface() || is_abstract()) {
1652 ResourceMark rm(THREAD);
1653 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1654 : vmSymbols::java_lang_InstantiationException(), external_name());
1655 }
1656 if (this == vmClasses::Class_klass()) {
1657 ResourceMark rm(THREAD);
1658 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1659 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1660 }
1661 }
1662
1663 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1664 // Need load-acquire for lock-free read
1665 if (array_klasses_acquire() == nullptr) {
1666
1667 // Recursively lock array allocation
1668 RecursiveLocker rl(MultiArray_lock, THREAD);
1669
1670 // Check if another thread created the array klass while we were waiting for the lock.
1671 if (array_klasses() == nullptr) {
1672 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1673 // use 'release' to pair with lock-free load
1674 release_set_array_klasses(k);
1675 }
1676 }
1677
1678 // array_klasses() will always be set at this point
1679 ObjArrayKlass* ak = array_klasses();
1680 assert(ak != nullptr, "should be set");
1681 return ak->array_klass(n, THREAD);
1682 }
1683
1684 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1685 // Need load-acquire for lock-free read
1686 ObjArrayKlass* oak = array_klasses_acquire();
1687 if (oak == nullptr) {
1688 return nullptr;
1689 } else {
1690 return oak->array_klass_or_null(n);
1691 }
1692 }
1693
1694 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1695 return array_klass(1, THREAD);
1696 }
1697
1698 ArrayKlass* InstanceKlass::array_klass_or_null() {
1699 return array_klass_or_null(1);
1700 }
1701
1702 static int call_class_initializer_counter = 0; // for debugging
1703
1704 Method* InstanceKlass::class_initializer() const {
1705 Method* clinit = find_method(
1706 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1707 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1708 return clinit;
1709 }
1710 return nullptr;
1711 }
1712
1713 void InstanceKlass::call_class_initializer(TRAPS) {
1714 if (ReplayCompiles &&
1715 (ReplaySuppressInitializers == 1 ||
1716 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1717 // Hide the existence of the initializer for the purpose of replaying the compile
1718 return;
1719 }
1720
1721 #if INCLUDE_CDS
1722 // This is needed to ensure the consistency of the archived heap objects.
1723 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1724 AOTClassInitializer::call_runtime_setup(THREAD, this);
1725 return;
1726 } else if (has_archived_enum_objs()) {
1727 assert(in_aot_cache(), "must be");
1728 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1729 if (initialized) {
1730 return;
1731 }
1732 }
1733 #endif
1734
1735 methodHandle h_method(THREAD, class_initializer());
1736 assert(!is_initialized(), "we cannot initialize twice");
1737 LogTarget(Info, class, init) lt;
1738 if (lt.is_enabled()) {
1739 ResourceMark rm(THREAD);
1740 LogStream ls(lt);
1741 ls.print("%d Initializing ", call_class_initializer_counter++);
1742 name()->print_value_on(&ls);
1743 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1744 h_method() == nullptr ? "(no method)" : "", p2i(this),
1745 THREAD->name());
1746 }
1747 if (h_method() != nullptr) {
1748 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1749 JavaCallArguments args; // No arguments
1750 JavaValue result(T_VOID);
1751 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1752 }
1753 }
1754
1755 // If a class that implements this interface is initialized, is the JVM required
1756 // to first execute a <clinit> method declared in this interface,
1757 // or (if also_check_supers==true) any of the super types of this interface?
1758 //
1759 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1760 // an interface, then let SC be its superclass and let SI1, ..., SIn
1761 // be all superinterfaces of C (whether direct or indirect) that
1762 // declare at least one non-abstract, non-static method.
1763 //
1764 // So when an interface is initialized, it does not look at its
1765 // supers. But a proper class will ensure that all of its supers have
1766 // run their <clinit> methods, except that it disregards interfaces
1767 // that lack a non-static concrete method (i.e., a default method).
1768 // Therefore, you should probably call this method only when the
1769 // current class is a super of some proper class, not an interface.
1770 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1771 assert(is_interface(), "must be");
1772
1773 if (!has_nonstatic_concrete_methods()) {
1774 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1775 return false;
1776 }
1777
1778 // JVMS 5.5. Initialization
1779 // ...If C is an interface that declares a non-abstract,
1780 // non-static method, the initialization of a class that
1781 // implements C directly or indirectly.
1782 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1783 return true;
1784 }
1785 if (also_check_supers) {
1786 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1787 for (int i = 0; i < all_ifs->length(); ++i) {
1788 InstanceKlass* super_intf = all_ifs->at(i);
1789 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1790 return true;
1791 }
1792 }
1793 }
1794 return false;
1795 }
1796
1797 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1798 InterpreterOopMap* entry_for) {
1799 // Lazily create the _oop_map_cache at first request.
1800 // Load_acquire is needed to safely get instance published with CAS by another thread.
1801 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
1802 if (oop_map_cache == nullptr) {
1803 // Try to install new instance atomically.
1804 oop_map_cache = new OopMapCache();
1805 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1806 if (other != nullptr) {
1807 // Someone else managed to install before us, ditch local copy and use the existing one.
1808 delete oop_map_cache;
1809 oop_map_cache = other;
1810 }
1811 }
1812 // _oop_map_cache is constant after init; lookup below does its own locking.
1813 oop_map_cache->lookup(method, bci, entry_for);
1814 }
1815
1816 bool InstanceKlass::contains_field_offset(int offset) {
1817 fieldDescriptor fd;
1818 return find_field_from_offset(offset, false, &fd);
1819 }
1820
1821 FieldInfo InstanceKlass::field(int index) const {
1822 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1823 if (fs.index() == index) {
1824 return fs.to_FieldInfo();
1825 }
1826 }
1827 fatal("Field not found");
1828 return FieldInfo();
1829 }
1830
1831 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1832 JavaFieldStream fs(this);
1833 if (fs.lookup(name, sig)) {
1834 assert(fs.name() == name, "name must match");
1835 assert(fs.signature() == sig, "signature must match");
1836 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1837 return true;
1838 }
1839 return false;
1840 }
1841
1842
1843 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1844 const int n = local_interfaces()->length();
1845 for (int i = 0; i < n; i++) {
1846 InstanceKlass* intf1 = local_interfaces()->at(i);
1847 assert(intf1->is_interface(), "just checking type");
1848 // search for field in current interface
1849 if (intf1->find_local_field(name, sig, fd)) {
1850 assert(fd->is_static(), "interface field must be static");
1851 return intf1;
1852 }
1853 // search for field in direct superinterfaces
1854 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
1855 if (intf2 != nullptr) return intf2;
1856 }
1857 // otherwise field lookup fails
1858 return nullptr;
1859 }
1860
1861
1862 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1863 // search order according to newest JVM spec (5.4.3.2, p.167).
1864 // 1) search for field in current klass
1865 if (find_local_field(name, sig, fd)) {
1866 return const_cast<InstanceKlass*>(this);
1867 }
1868 // 2) search for field recursively in direct superinterfaces
1869 { Klass* intf = find_interface_field(name, sig, fd);
1870 if (intf != nullptr) return intf;
1871 }
1872 // 3) apply field lookup recursively if superclass exists
1873 { InstanceKlass* supr = super();
1874 if (supr != nullptr) return supr->find_field(name, sig, fd);
1875 }
1876 // 4) otherwise field lookup fails
1877 return nullptr;
1878 }
1879
1880
1881 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1882 // search order according to newest JVM spec (5.4.3.2, p.167).
1883 // 1) search for field in current klass
1884 if (find_local_field(name, sig, fd)) {
1885 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1886 }
1887 // 2) search for field recursively in direct superinterfaces
1888 if (is_static) {
1889 Klass* intf = find_interface_field(name, sig, fd);
1890 if (intf != nullptr) return intf;
1891 }
1892 // 3) apply field lookup recursively if superclass exists
1893 { InstanceKlass* supr = super();
1894 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
1895 }
1896 // 4) otherwise field lookup fails
1897 return nullptr;
1898 }
1899
1900
1901 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1902 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1903 if (fs.offset() == offset) {
1904 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1905 if (fd->is_static() == is_static) return true;
1906 }
1907 }
1908 return false;
1909 }
1910
1911
1912 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1913 const InstanceKlass* klass = this;
1914 while (klass != nullptr) {
1915 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
1916 return true;
1917 }
1918 klass = klass->super();
1919 }
1920 return false;
1921 }
1922
1923
1924 void InstanceKlass::methods_do(void f(Method* method)) {
1925 // Methods aren't stable until they are loaded. This can be read outside
1926 // a lock through the ClassLoaderData for profiling
1927 // Redefined scratch classes are on the list and need to be cleaned
1928 if (!is_loaded() && !is_scratch_class()) {
1929 return;
1930 }
1931
1932 int len = methods()->length();
1933 for (int index = 0; index < len; index++) {
1934 Method* m = methods()->at(index);
1935 assert(m->is_method(), "must be method");
1936 f(m);
1937 }
1938 }
1939
1940
1941 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1942 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1943 if (fs.access_flags().is_static()) {
1944 fieldDescriptor& fd = fs.field_descriptor();
1945 cl->do_field(&fd);
1946 }
1947 }
1948 }
1949
1950
1951 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1952 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1953 if (fs.access_flags().is_static()) {
1954 fieldDescriptor& fd = fs.field_descriptor();
1955 f(&fd, mirror, CHECK);
1956 }
1957 }
1958 }
1959
1960 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1961 InstanceKlass* super = this->super();
1962 if (super != nullptr) {
1963 super->do_nonstatic_fields(cl);
1964 }
1965 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1966 fieldDescriptor& fd = fs.field_descriptor();
1967 if (!fd.is_static()) {
1968 cl->do_field(&fd);
1969 }
1970 }
1971 }
1972
1973 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
1974 return a->offset() - b->offset();
1975 }
1976
1977 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1978 InstanceKlass* super = this->super();
1979 if (super != nullptr) {
1980 super->print_nonstatic_fields(cl);
1981 }
1982 ResourceMark rm;
1983 // In DebugInfo nonstatic fields are sorted by offset.
1984 GrowableArray<FieldInfo> fields_sorted;
1985 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1986 if (!fs.access_flags().is_static()) {
1987 fields_sorted.push(fs.to_FieldInfo());
1988 }
1989 }
1990 int length = fields_sorted.length();
1991 if (length > 0) {
1992 fields_sorted.sort(compare_fields_by_offset);
1993 fieldDescriptor fd;
1994 for (int i = 0; i < length; i++) {
1995 fd.reinitialize(this, fields_sorted.at(i));
1996 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
1997 cl->do_field(&fd);
1998 }
1999 }
2000 }
2001
2002 #ifdef ASSERT
2003 static int linear_search(const Array<Method*>* methods,
2004 const Symbol* name,
2005 const Symbol* signature) {
2006 const int len = methods->length();
2007 for (int index = 0; index < len; index++) {
2008 const Method* const m = methods->at(index);
2009 assert(m->is_method(), "must be method");
2010 if (m->signature() == signature && m->name() == name) {
2011 return index;
2012 }
2013 }
2014 return -1;
2015 }
2016 #endif
2017
2018 bool InstanceKlass::_disable_method_binary_search = false;
2019
2020 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2021 int len = methods->length();
2022 int l = 0;
2023 int h = len - 1;
2024 while (l <= h) {
2025 Method* m = methods->at(l);
2026 if (m->name() == name) {
2027 return l;
2028 }
2029 l++;
2030 }
2031 return -1;
2032 }
2033
2034 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2035 if (_disable_method_binary_search) {
2036 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2037 // At the final stage of dynamic dumping, the methods array may not be sorted
2038 // by ascending addresses of their names, so we can't use binary search anymore.
2039 // However, methods with the same name are still laid out consecutively inside the
2040 // methods array, so let's look for the first one that matches.
2041 return linear_search(methods, name);
2042 }
2043
2044 int len = methods->length();
2045 int l = 0;
2046 int h = len - 1;
2047
2048 // methods are sorted by ascending addresses of their names, so do binary search
2049 while (l <= h) {
2050 int mid = (l + h) >> 1;
2051 Method* m = methods->at(mid);
2052 assert(m->is_method(), "must be method");
2053 int res = m->name()->fast_compare(name);
2054 if (res == 0) {
2055 return mid;
2056 } else if (res < 0) {
2057 l = mid + 1;
2058 } else {
2059 h = mid - 1;
2060 }
2061 }
2062 return -1;
2063 }
2064
2065 // find_method looks up the name/signature in the local methods array
2066 Method* InstanceKlass::find_method(const Symbol* name,
2067 const Symbol* signature) const {
2068 return find_method_impl(name, signature,
2069 OverpassLookupMode::find,
2070 StaticLookupMode::find,
2071 PrivateLookupMode::find);
2072 }
2073
2074 Method* InstanceKlass::find_method_impl(const Symbol* name,
2075 const Symbol* signature,
2076 OverpassLookupMode overpass_mode,
2077 StaticLookupMode static_mode,
2078 PrivateLookupMode private_mode) const {
2079 return InstanceKlass::find_method_impl(methods(),
2080 name,
2081 signature,
2082 overpass_mode,
2083 static_mode,
2084 private_mode);
2085 }
2086
2087 // find_instance_method looks up the name/signature in the local methods array
2088 // and skips over static methods
2089 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2090 const Symbol* name,
2091 const Symbol* signature,
2092 PrivateLookupMode private_mode) {
2093 Method* const meth = InstanceKlass::find_method_impl(methods,
2094 name,
2095 signature,
2096 OverpassLookupMode::find,
2097 StaticLookupMode::skip,
2098 private_mode);
2099 assert(((meth == nullptr) || !meth->is_static()),
2100 "find_instance_method should have skipped statics");
2101 return meth;
2102 }
2103
2104 // find_instance_method looks up the name/signature in the local methods array
2105 // and skips over static methods
2106 Method* InstanceKlass::find_instance_method(const Symbol* name,
2107 const Symbol* signature,
2108 PrivateLookupMode private_mode) const {
2109 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2110 }
2111
2112 // Find looks up the name/signature in the local methods array
2113 // and filters on the overpass, static and private flags
2114 // This returns the first one found
2115 // note that the local methods array can have up to one overpass, one static
2116 // and one instance (private or not) with the same name/signature
2117 Method* InstanceKlass::find_local_method(const Symbol* name,
2118 const Symbol* signature,
2119 OverpassLookupMode overpass_mode,
2120 StaticLookupMode static_mode,
2121 PrivateLookupMode private_mode) const {
2122 return InstanceKlass::find_method_impl(methods(),
2123 name,
2124 signature,
2125 overpass_mode,
2126 static_mode,
2127 private_mode);
2128 }
2129
2130 // Find looks up the name/signature in the local methods array
2131 // and filters on the overpass, static and private flags
2132 // This returns the first one found
2133 // note that the local methods array can have up to one overpass, one static
2134 // and one instance (private or not) with the same name/signature
2135 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2136 const Symbol* name,
2137 const Symbol* signature,
2138 OverpassLookupMode overpass_mode,
2139 StaticLookupMode static_mode,
2140 PrivateLookupMode private_mode) {
2141 return InstanceKlass::find_method_impl(methods,
2142 name,
2143 signature,
2144 overpass_mode,
2145 static_mode,
2146 private_mode);
2147 }
2148
2149 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2150 const Symbol* name,
2151 const Symbol* signature) {
2152 return InstanceKlass::find_method_impl(methods,
2153 name,
2154 signature,
2155 OverpassLookupMode::find,
2156 StaticLookupMode::find,
2157 PrivateLookupMode::find);
2158 }
2159
2160 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2161 const Symbol* name,
2162 const Symbol* signature,
2163 OverpassLookupMode overpass_mode,
2164 StaticLookupMode static_mode,
2165 PrivateLookupMode private_mode) {
2166 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2167 return hit >= 0 ? methods->at(hit): nullptr;
2168 }
2169
2170 // true if method matches signature and conforms to skipping_X conditions.
2171 static bool method_matches(const Method* m,
2172 const Symbol* signature,
2173 bool skipping_overpass,
2174 bool skipping_static,
2175 bool skipping_private) {
2176 return ((m->signature() == signature) &&
2177 (!skipping_overpass || !m->is_overpass()) &&
2178 (!skipping_static || !m->is_static()) &&
2179 (!skipping_private || !m->is_private()));
2180 }
2181
2182 // Used directly for default_methods to find the index into the
2183 // default_vtable_indices, and indirectly by find_method
2184 // find_method_index looks in the local methods array to return the index
2185 // of the matching name/signature. If, overpass methods are being ignored,
2186 // the search continues to find a potential non-overpass match. This capability
2187 // is important during method resolution to prefer a static method, for example,
2188 // over an overpass method.
2189 // There is the possibility in any _method's array to have the same name/signature
2190 // for a static method, an overpass method and a local instance method
2191 // To correctly catch a given method, the search criteria may need
2192 // to explicitly skip the other two. For local instance methods, it
2193 // is often necessary to skip private methods
2194 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2195 const Symbol* name,
2196 const Symbol* signature,
2197 OverpassLookupMode overpass_mode,
2198 StaticLookupMode static_mode,
2199 PrivateLookupMode private_mode) {
2200 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2201 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2202 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2203 const int hit = quick_search(methods, name);
2204 if (hit != -1) {
2205 const Method* const m = methods->at(hit);
2206
2207 // Do linear search to find matching signature. First, quick check
2208 // for common case, ignoring overpasses if requested.
2209 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2210 return hit;
2211 }
2212
2213 // search downwards through overloaded methods
2214 int i;
2215 for (i = hit - 1; i >= 0; --i) {
2216 const Method* const m = methods->at(i);
2217 assert(m->is_method(), "must be method");
2218 if (m->name() != name) {
2219 break;
2220 }
2221 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2222 return i;
2223 }
2224 }
2225 // search upwards
2226 for (i = hit + 1; i < methods->length(); ++i) {
2227 const Method* const m = methods->at(i);
2228 assert(m->is_method(), "must be method");
2229 if (m->name() != name) {
2230 break;
2231 }
2232 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2233 return i;
2234 }
2235 }
2236 // not found
2237 #ifdef ASSERT
2238 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2239 linear_search(methods, name, signature);
2240 assert(-1 == index, "binary search should have found entry %d", index);
2241 #endif
2242 }
2243 return -1;
2244 }
2245
2246 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2247 return find_method_by_name(methods(), name, end);
2248 }
2249
2250 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2251 const Symbol* name,
2252 int* end_ptr) {
2253 assert(end_ptr != nullptr, "just checking");
2254 int start = quick_search(methods, name);
2255 int end = start + 1;
2256 if (start != -1) {
2257 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2258 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2259 *end_ptr = end;
2260 return start;
2261 }
2262 return -1;
2263 }
2264
2265 // uncached_lookup_method searches both the local class methods array and all
2266 // superclasses methods arrays, skipping any overpass methods in superclasses,
2267 // and possibly skipping private methods.
2268 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2269 const Symbol* signature,
2270 OverpassLookupMode overpass_mode,
2271 PrivateLookupMode private_mode) const {
2272 OverpassLookupMode overpass_local_mode = overpass_mode;
2273 const InstanceKlass* klass = this;
2274 while (klass != nullptr) {
2275 Method* const method = klass->find_method_impl(name,
2276 signature,
2277 overpass_local_mode,
2278 StaticLookupMode::find,
2279 private_mode);
2280 if (method != nullptr) {
2281 return method;
2282 }
2283 klass = klass->super();
2284 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2285 }
2286 return nullptr;
2287 }
2288
2289 #ifdef ASSERT
2290 // search through class hierarchy and return true if this class or
2291 // one of the superclasses was redefined
2292 bool InstanceKlass::has_redefined_this_or_super() const {
2293 const InstanceKlass* klass = this;
2294 while (klass != nullptr) {
2295 if (klass->has_been_redefined()) {
2296 return true;
2297 }
2298 klass = klass->super();
2299 }
2300 return false;
2301 }
2302 #endif
2303
2304 // lookup a method in the default methods list then in all transitive interfaces
2305 // Do NOT return private or static methods
2306 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2307 Symbol* signature) const {
2308 Method* m = nullptr;
2309 if (default_methods() != nullptr) {
2310 m = find_method(default_methods(), name, signature);
2311 }
2312 // Look up interfaces
2313 if (m == nullptr) {
2314 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2315 }
2316 return m;
2317 }
2318
2319 // lookup a method in all the interfaces that this class implements
2320 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2321 // They should only be found in the initial InterfaceMethodRef
2322 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2323 Symbol* signature,
2324 DefaultsLookupMode defaults_mode) const {
2325 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2326 int num_ifs = all_ifs->length();
2327 InstanceKlass *ik = nullptr;
2328 for (int i = 0; i < num_ifs; i++) {
2329 ik = all_ifs->at(i);
2330 Method* m = ik->lookup_method(name, signature);
2331 if (m != nullptr && m->is_public() && !m->is_static() &&
2332 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2333 return m;
2334 }
2335 }
2336 return nullptr;
2337 }
2338
2339 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2340 :_st(st), _verbose(verbose) {
2341 ResourceMark rm;
2342 _st->print("%-18s ", "KlassAddr");
2343 _st->print("%-4s ", "Size");
2344 _st->print("%-20s ", "State");
2345 _st->print("%-7s ", "Flags");
2346 _st->print("%-5s ", "ClassName");
2347 _st->cr();
2348 }
2349
2350 void PrintClassClosure::do_klass(Klass* k) {
2351 ResourceMark rm;
2352 // klass pointer
2353 _st->print(PTR_FORMAT " ", p2i(k));
2354 // klass size
2355 _st->print("%4d ", k->size());
2356 // initialization state
2357 if (k->is_instance_klass()) {
2358 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2359 } else {
2360 _st->print("%-20s ","");
2361 }
2362 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2363 char buf[10];
2364 int i = 0;
2365 if (k->has_finalizer()) buf[i++] = 'F';
2366 if (k->is_instance_klass()) {
2367 InstanceKlass* ik = InstanceKlass::cast(k);
2368 if (ik->has_final_method()) buf[i++] = 'f';
2369 if (ik->is_rewritten()) buf[i++] = 'W';
2370 if (ik->is_contended()) buf[i++] = 'C';
2371 if (ik->has_been_redefined()) buf[i++] = 'R';
2372 if (ik->in_aot_cache()) buf[i++] = 'S';
2373 }
2374 buf[i++] = '\0';
2375 _st->print("%-7s ", buf);
2376 // klass name
2377 _st->print("%-5s ", k->external_name());
2378 // end
2379 _st->cr();
2380 if (_verbose) {
2381 k->print_on(_st);
2382 }
2383 }
2384
2385 /* jni_id_for for jfieldIds only */
2386 JNIid* InstanceKlass::jni_id_for(int offset) {
2387 MutexLocker ml(JfieldIdCreation_lock);
2388 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2389 if (probe == nullptr) {
2390 // Allocate new static field identifier
2391 probe = new JNIid(this, offset, jni_ids());
2392 set_jni_ids(probe);
2393 }
2394 return probe;
2395 }
2396
2397 u2 InstanceKlass::enclosing_method_data(int offset) const {
2398 const Array<jushort>* const inner_class_list = inner_classes();
2399 if (inner_class_list == nullptr) {
2400 return 0;
2401 }
2402 const int length = inner_class_list->length();
2403 if (length % inner_class_next_offset == 0) {
2404 return 0;
2405 }
2406 const int index = length - enclosing_method_attribute_size;
2407 assert(offset < enclosing_method_attribute_size, "invalid offset");
2408 return inner_class_list->at(index + offset);
2409 }
2410
2411 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2412 u2 method_index) {
2413 Array<jushort>* inner_class_list = inner_classes();
2414 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2415 int length = inner_class_list->length();
2416 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2417 int index = length - enclosing_method_attribute_size;
2418 inner_class_list->at_put(
2419 index + enclosing_method_class_index_offset, class_index);
2420 inner_class_list->at_put(
2421 index + enclosing_method_method_index_offset, method_index);
2422 }
2423 }
2424
2425 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2426 if (method->is_old() && !method->is_obsolete()) {
2427 // If the method passed in is old (but not obsolete), use the current version.
2428 method = method_with_idnum((int)idnum);
2429 assert(method != nullptr, "old and but not obsolete, so should exist");
2430 }
2431 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2432 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2433 return new_id;
2434 }
2435
2436 // Allocate the jmethodID cache.
2437 static jmethodID* create_jmethod_id_cache(size_t size) {
2438 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2439 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2440 // cache size is stored in element[0], other elements offset by one
2441 jmeths[0] = (jmethodID)size;
2442 return jmeths;
2443 }
2444
2445 // When reading outside a lock, use this.
2446 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2447 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2448 }
2449
2450 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2451 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2452 }
2453
2454 // Lookup or create a jmethodID.
2455 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2456 int idnum = method->method_idnum();
2457 jmethodID* jmeths = methods_jmethod_ids_acquire();
2458
2459 // We use a double-check locking idiom here because this cache is
2460 // performance sensitive. In the normal system, this cache only
2461 // transitions from null to non-null which is safe because we use
2462 // release_set_methods_jmethod_ids() to advertise the new cache.
2463 // A partially constructed cache should never be seen by a racing
2464 // thread. We also use release_store() to save a new jmethodID
2465 // in the cache so a partially constructed jmethodID should never be
2466 // seen either. Cache reads of existing jmethodIDs proceed without a
2467 // lock, but cache writes of a new jmethodID requires uniqueness and
2468 // creation of the cache itself requires no leaks so a lock is
2469 // acquired in those two cases.
2470 //
2471 // If the RedefineClasses() API has been used, then this cache grows
2472 // in the redefinition safepoint.
2473
2474 if (jmeths == nullptr) {
2475 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2476 jmeths = _methods_jmethod_ids;
2477 // Still null?
2478 if (jmeths == nullptr) {
2479 size_t size = idnum_allocated_count();
2480 assert(size > (size_t)idnum, "should already have space");
2481 jmeths = create_jmethod_id_cache(size);
2482 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2483
2484 // publish jmeths
2485 release_set_methods_jmethod_ids(jmeths);
2486 return new_id;
2487 }
2488 }
2489
2490 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2491 if (id == nullptr) {
2492 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2493 id = jmeths[idnum + 1];
2494 // Still null?
2495 if (id == nullptr) {
2496 return update_jmethod_id(jmeths, method, idnum);
2497 }
2498 }
2499 return id;
2500 }
2501
2502 void InstanceKlass::update_methods_jmethod_cache() {
2503 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2504 jmethodID* cache = _methods_jmethod_ids;
2505 if (cache != nullptr) {
2506 size_t size = idnum_allocated_count();
2507 size_t old_size = (size_t)cache[0];
2508 if (old_size < size + 1) {
2509 // Allocate a larger one and copy entries to the new one.
2510 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2511 jmethodID* new_cache = create_jmethod_id_cache(size);
2512
2513 for (int i = 1; i <= (int)old_size; i++) {
2514 new_cache[i] = cache[i];
2515 }
2516 _methods_jmethod_ids = new_cache;
2517 FREE_C_HEAP_ARRAY(jmethodID, cache);
2518 }
2519 }
2520 }
2521
2522 // Make a jmethodID for all methods in this class. This makes getting all method
2523 // ids much, much faster with classes with more than 8
2524 // methods, and has a *substantial* effect on performance with jvmti
2525 // code that loads all jmethodIDs for all classes.
2526 void InstanceKlass::make_methods_jmethod_ids() {
2527 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2528 jmethodID* jmeths = _methods_jmethod_ids;
2529 if (jmeths == nullptr) {
2530 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2531 release_set_methods_jmethod_ids(jmeths);
2532 }
2533
2534 int length = methods()->length();
2535 for (int index = 0; index < length; index++) {
2536 Method* m = methods()->at(index);
2537 int idnum = m->method_idnum();
2538 assert(!m->is_old(), "should not have old methods or I'm confused");
2539 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2540 if (!m->is_overpass() && // skip overpasses
2541 id == nullptr) {
2542 id = Method::make_jmethod_id(class_loader_data(), m);
2543 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2544 }
2545 }
2546 }
2547
2548 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2549 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2550 int idnum = method->method_idnum();
2551 jmethodID* jmeths = methods_jmethod_ids_acquire();
2552 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2553 }
2554
2555 inline DependencyContext InstanceKlass::dependencies() {
2556 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2557 return dep_context;
2558 }
2559
2560 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2561 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2562 }
2563
2564 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2565 assert_lock_strong(CodeCache_lock);
2566 dependencies().add_dependent_nmethod(nm);
2567 }
2568
2569 void InstanceKlass::clean_dependency_context() {
2570 dependencies().clean_unloading_dependents();
2571 }
2572
2573 #ifndef PRODUCT
2574 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2575 dependencies().print_dependent_nmethods(verbose);
2576 }
2577
2578 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2579 return dependencies().is_dependent_nmethod(nm);
2580 }
2581 #endif //PRODUCT
2582
2583 void InstanceKlass::clean_weak_instanceklass_links() {
2584 clean_implementors_list();
2585 clean_method_data();
2586 }
2587
2588 void InstanceKlass::clean_implementors_list() {
2589 assert(is_loader_alive(), "this klass should be live");
2590 if (is_interface()) {
2591 assert (ClassUnloading, "only called for ClassUnloading");
2592 for (;;) {
2593 // Use load_acquire due to competing with inserts
2594 InstanceKlass* volatile* iklass = adr_implementor();
2595 assert(iklass != nullptr, "Klass must not be null");
2596 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2597 if (impl != nullptr && !impl->is_loader_alive()) {
2598 // null this field, might be an unloaded instance klass or null
2599 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2600 // Successfully unlinking implementor.
2601 if (log_is_enabled(Trace, class, unload)) {
2602 ResourceMark rm;
2603 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2604 }
2605 return;
2606 }
2607 } else {
2608 return;
2609 }
2610 }
2611 }
2612 }
2613
2614 void InstanceKlass::clean_method_data() {
2615 for (int m = 0; m < methods()->length(); m++) {
2616 MethodData* mdo = methods()->at(m)->method_data();
2617 if (mdo != nullptr) {
2618 mdo->clean_method_data(/*always_clean*/false);
2619 }
2620 }
2621 }
2622
2623 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2624 Klass::metaspace_pointers_do(it);
2625
2626 if (log_is_enabled(Trace, aot)) {
2627 ResourceMark rm;
2628 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2629 }
2630
2631 it->push(&_annotations);
2632 it->push((Klass**)&_array_klasses);
2633 if (!is_rewritten()) {
2634 it->push(&_constants, MetaspaceClosure::_writable);
2635 } else {
2636 it->push(&_constants);
2637 }
2638 it->push(&_inner_classes);
2639 #if INCLUDE_JVMTI
2640 it->push(&_previous_versions);
2641 #endif
2642 #if INCLUDE_CDS
2643 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2644 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2645 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2646 // The length check on the _methods is necessary because classes which don't have any
2647 // methods share the Universe::_the_empty_method_array which is in the RO region.
2648 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2649 // To handle jsr bytecode, new Method* maybe stored into _methods
2650 it->push(&_methods, MetaspaceClosure::_writable);
2651 } else {
2652 #endif
2653 it->push(&_methods);
2654 #if INCLUDE_CDS
2655 }
2656 #endif
2657 it->push(&_default_methods);
2658 it->push(&_local_interfaces);
2659 it->push(&_transitive_interfaces);
2660 it->push(&_method_ordering);
2661 if (!is_rewritten()) {
2662 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2663 } else {
2664 it->push(&_default_vtable_indices);
2665 }
2666
2667 it->push(&_fieldinfo_stream);
2668 it->push(&_fieldinfo_search_table);
2669 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2670 it->push(&_fields_status, MetaspaceClosure::_writable);
2671
2672 if (itable_length() > 0) {
2673 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2674 int method_table_offset_in_words = ioe->offset()/wordSize;
2675 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2676
2677 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2678 / itableOffsetEntry::size();
2679
2680 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2681 if (ioe->interface_klass() != nullptr) {
2682 it->push(ioe->interface_klass_addr());
2683 itableMethodEntry* ime = ioe->first_method_entry(this);
2684 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2685 for (int index = 0; index < n; index ++) {
2686 it->push(ime[index].method_addr());
2687 }
2688 }
2689 }
2690 }
2691
2692 it->push(&_nest_host);
2693 it->push(&_nest_members);
2694 it->push(&_permitted_subclasses);
2695 it->push(&_record_components);
2696 }
2697
2698 #if INCLUDE_CDS
2699 void InstanceKlass::remove_unshareable_info() {
2700
2701 if (is_linked()) {
2702 assert(can_be_verified_at_dumptime(), "must be");
2703 // Remember this so we can avoid walking the hierarchy at runtime.
2704 set_verified_at_dump_time();
2705 }
2706
2707 _misc_flags.set_has_init_deps_processed(false);
2708
2709 Klass::remove_unshareable_info();
2710
2711 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2712 // Classes are attempted to link during dumping and may fail,
2713 // but these classes are still in the dictionary and class list in CLD.
2714 // If the class has failed verification, there is nothing else to remove.
2715 return;
2716 }
2717
2718 // Reset to the 'allocated' state to prevent any premature accessing to
2719 // a shared class at runtime while the class is still being loaded and
2720 // restored. A class' init_state is set to 'loaded' at runtime when it's
2721 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2722 _init_state = allocated;
2723
2724 { // Otherwise this needs to take out the Compile_lock.
2725 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2726 init_implementor();
2727 }
2728
2729 // Call remove_unshareable_info() on other objects that belong to this class, except
2730 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2731 // ArchiveBuilder::make_klasses_shareable(),
2732
2733 for (int i = 0; i < methods()->length(); i++) {
2734 Method* m = methods()->at(i);
2735 m->remove_unshareable_info();
2736 }
2737
2738 // do array classes also.
2739 if (array_klasses() != nullptr) {
2740 array_klasses()->remove_unshareable_info();
2741 }
2742
2743 // These are not allocated from metaspace. They are safe to set to null.
2744 _source_debug_extension = nullptr;
2745 _dep_context = nullptr;
2746 _osr_nmethods_head = nullptr;
2747 #if INCLUDE_JVMTI
2748 _breakpoints = nullptr;
2749 _previous_versions = nullptr;
2750 _cached_class_file = nullptr;
2751 _jvmti_cached_class_field_map = nullptr;
2752 #endif
2753
2754 _init_thread = nullptr;
2755 _methods_jmethod_ids = nullptr;
2756 _jni_ids = nullptr;
2757 _oop_map_cache = nullptr;
2758 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2759 // keep _nest_host
2760 } else {
2761 // clear _nest_host to ensure re-load at runtime
2762 _nest_host = nullptr;
2763 }
2764 init_shared_package_entry();
2765 _dep_context_last_cleaned = 0;
2766 DEBUG_ONLY(_shared_class_load_count = 0);
2767
2768 remove_unshareable_flags();
2769
2770 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2771 }
2772
2773 void InstanceKlass::remove_unshareable_flags() {
2774 // clear all the flags/stats that shouldn't be in the archived version
2775 assert(!is_scratch_class(), "must be");
2776 assert(!has_been_redefined(), "must be");
2777 #if INCLUDE_JVMTI
2778 set_is_being_redefined(false);
2779 #endif
2780 set_has_resolved_methods(false);
2781 }
2782
2783 void InstanceKlass::remove_java_mirror() {
2784 Klass::remove_java_mirror();
2785
2786 // do array classes also.
2787 if (array_klasses() != nullptr) {
2788 array_klasses()->remove_java_mirror();
2789 }
2790 }
2791
2792 void InstanceKlass::init_shared_package_entry() {
2793 assert(CDSConfig::is_dumping_archive(), "must be");
2794 #if !INCLUDE_CDS_JAVA_HEAP
2795 _package_entry = nullptr;
2796 #else
2797 if (CDSConfig::is_dumping_full_module_graph()) {
2798 if (defined_by_other_loaders()) {
2799 _package_entry = nullptr;
2800 } else {
2801 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2802 }
2803 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2804 CDSConfig::is_using_full_module_graph() &&
2805 AOTMetaspace::in_aot_cache(_package_entry)) {
2806 // _package_entry is an archived package in the base archive. Leave it as is.
2807 } else {
2808 _package_entry = nullptr;
2809 }
2810 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2811 #endif
2812 }
2813
2814 void InstanceKlass::compute_has_loops_flag_for_methods() {
2815 Array<Method*>* methods = this->methods();
2816 for (int index = 0; index < methods->length(); ++index) {
2817 Method* m = methods->at(index);
2818 if (!m->is_overpass()) { // work around JDK-8305771
2819 m->compute_has_loops_flag();
2820 }
2821 }
2822 }
2823
2824 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2825 PackageEntry* pkg_entry, TRAPS) {
2826 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2827 // before the InstanceKlass is added to the SystemDictionary. Make
2828 // sure the current state is <loaded.
2829 assert(!is_loaded(), "invalid init state");
2830 assert(!shared_loading_failed(), "Must not try to load failed class again");
2831 set_package(loader_data, pkg_entry, CHECK);
2832 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2833
2834 Array<Method*>* methods = this->methods();
2835 int num_methods = methods->length();
2836 for (int index = 0; index < num_methods; ++index) {
2837 methods->at(index)->restore_unshareable_info(CHECK);
2838 }
2839 #if INCLUDE_JVMTI
2840 if (JvmtiExport::has_redefined_a_class()) {
2841 // Reinitialize vtable because RedefineClasses may have changed some
2842 // entries in this vtable for super classes so the CDS vtable might
2843 // point to old or obsolete entries. RedefineClasses doesn't fix up
2844 // vtables in the shared system dictionary, only the main one.
2845 // It also redefines the itable too so fix that too.
2846 // First fix any default methods that point to a super class that may
2847 // have been redefined.
2848 bool trace_name_printed = false;
2849 adjust_default_methods(&trace_name_printed);
2850 if (verified_at_dump_time()) {
2851 // Initialize vtable and itable for classes which can be verified at dump time.
2852 // Unlinked classes such as old classes with major version < 50 cannot be verified
2853 // at dump time.
2854 vtable().initialize_vtable();
2855 itable().initialize_itable();
2856 }
2857 }
2858 #endif // INCLUDE_JVMTI
2859
2860 // restore constant pool resolved references
2861 constants()->restore_unshareable_info(CHECK);
2862
2863 if (array_klasses() != nullptr) {
2864 // To get a consistent list of classes we need MultiArray_lock to ensure
2865 // array classes aren't observed while they are being restored.
2866 RecursiveLocker rl(MultiArray_lock, THREAD);
2867 assert(this == array_klasses()->bottom_klass(), "sanity");
2868 // Array classes have null protection domain.
2869 // --> see ArrayKlass::complete_create_array_klass()
2870 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2871 }
2872
2873 // Initialize @ValueBased class annotation if not already set in the archived klass.
2874 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2875 set_is_value_based();
2876 }
2877
2878 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2879 }
2880
2881 bool InstanceKlass::can_be_verified_at_dumptime() const {
2882 if (CDSConfig::is_dumping_dynamic_archive() && AOTMetaspace::in_aot_cache(this)) {
2883 // This is a class that was dumped into the base archive, so we know
2884 // it was verified at dump time.
2885 return true;
2886 }
2887
2888 if (CDSConfig::is_preserving_verification_constraints()) {
2889 return true;
2890 }
2891
2892 if (CDSConfig::is_old_class_for_verifier(this)) {
2893 // The old verifier does not save verification constraints, so at run time
2894 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
2895 return false;
2896 }
2897 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
2898 return false;
2899 }
2900 Array<InstanceKlass*>* interfaces = local_interfaces();
2901 int len = interfaces->length();
2902 for (int i = 0; i < len; i++) {
2903 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2904 return false;
2905 }
2906 }
2907 return true;
2908 }
2909
2910 #endif // INCLUDE_CDS
2911
2912 #if INCLUDE_JVMTI
2913 static void clear_all_breakpoints(Method* m) {
2914 m->clear_all_breakpoints();
2915 }
2916 #endif
2917
2918 void InstanceKlass::unload_class(InstanceKlass* ik) {
2919
2920 if (ik->is_scratch_class()) {
2921 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2922 return;
2923 }
2924 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2925
2926 // Release dependencies.
2927 ik->dependencies().remove_all_dependents();
2928
2929 // notify the debugger
2930 if (JvmtiExport::should_post_class_unload()) {
2931 JvmtiExport::post_class_unload(ik);
2932 }
2933
2934 // notify ClassLoadingService of class unload
2935 ClassLoadingService::notify_class_unloaded(ik);
2936
2937 SystemDictionaryShared::handle_class_unloading(ik);
2938
2939 if (log_is_enabled(Info, class, unload)) {
2940 ResourceMark rm;
2941 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2942 }
2943
2944 Events::log_class_unloading(Thread::current(), ik);
2945
2946 #if INCLUDE_JFR
2947 assert(ik != nullptr, "invariant");
2948 EventClassUnload event;
2949 event.set_unloadedClass(ik);
2950 event.set_definingClassLoader(ik->class_loader_data());
2951 event.commit();
2952 #endif
2953 }
2954
2955 static void method_release_C_heap_structures(Method* m) {
2956 m->release_C_heap_structures();
2957 }
2958
2959 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2960 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2961 // Clean up C heap
2962 Klass::release_C_heap_structures();
2963
2964 // Deallocate and call destructors for MDO mutexes
2965 if (release_sub_metadata) {
2966 methods_do(method_release_C_heap_structures);
2967 }
2968
2969 // Deallocate oop map cache
2970 if (_oop_map_cache != nullptr) {
2971 delete _oop_map_cache;
2972 _oop_map_cache = nullptr;
2973 }
2974
2975 // Deallocate JNI identifiers for jfieldIDs
2976 JNIid::deallocate(jni_ids());
2977 set_jni_ids(nullptr);
2978
2979 jmethodID* jmeths = _methods_jmethod_ids;
2980 if (jmeths != nullptr) {
2981 release_set_methods_jmethod_ids(nullptr);
2982 FreeHeap(jmeths);
2983 }
2984
2985 assert(_dep_context == nullptr,
2986 "dependencies should already be cleaned");
2987
2988 #if INCLUDE_JVMTI
2989 // Deallocate breakpoint records
2990 if (breakpoints() != nullptr) {
2991 methods_do(clear_all_breakpoints);
2992 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2993 }
2994
2995 // deallocate the cached class file
2996 if (_cached_class_file != nullptr) {
2997 os::free(_cached_class_file);
2998 _cached_class_file = nullptr;
2999 }
3000 #endif
3001
3002 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3003
3004 if (release_sub_metadata) {
3005 constants()->release_C_heap_structures();
3006 }
3007 }
3008
3009 // The constant pool is on stack if any of the methods are executing or
3010 // referenced by handles.
3011 bool InstanceKlass::on_stack() const {
3012 return _constants->on_stack();
3013 }
3014
3015 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3016 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3017 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3018
3019 // minor and major version numbers of class file
3020 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3021 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3022 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3023 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3024
3025 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3026 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3027 if (ik->constants()->version() == version) {
3028 return ik;
3029 }
3030 }
3031 return nullptr;
3032 }
3033
3034 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3035 if (array == nullptr) {
3036 _source_debug_extension = nullptr;
3037 } else {
3038 // Adding one to the attribute length in order to store a null terminator
3039 // character could cause an overflow because the attribute length is
3040 // already coded with an u4 in the classfile, but in practice, it's
3041 // unlikely to happen.
3042 assert((length+1) > length, "Overflow checking");
3043 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3044 for (int i = 0; i < length; i++) {
3045 sde[i] = array[i];
3046 }
3047 sde[length] = '\0';
3048 _source_debug_extension = sde;
3049 }
3050 }
3051
3052 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3053 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3054 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3055
3056 const char* InstanceKlass::signature_name() const {
3057
3058 // Get the internal name as a c string
3059 const char* src = (const char*) (name()->as_C_string());
3060 const int src_length = (int)strlen(src);
3061
3062 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3063
3064 // Add L as type indicator
3065 int dest_index = 0;
3066 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3067
3068 // Add the actual class name
3069 for (int src_index = 0; src_index < src_length; ) {
3070 dest[dest_index++] = src[src_index++];
3071 }
3072
3073 if (is_hidden()) { // Replace the last '+' with a '.'.
3074 for (int index = (int)src_length; index > 0; index--) {
3075 if (dest[index] == '+') {
3076 dest[index] = JVM_SIGNATURE_DOT;
3077 break;
3078 }
3079 }
3080 }
3081
3082 // Add the semicolon and the null
3083 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3084 dest[dest_index] = '\0';
3085 return dest;
3086 }
3087
3088 ModuleEntry* InstanceKlass::module() const {
3089 if (is_hidden() &&
3090 in_unnamed_package() &&
3091 class_loader_data()->has_class_mirror_holder()) {
3092 // For a non-strong hidden class defined to an unnamed package,
3093 // its (class held) CLD will not have an unnamed module created for it.
3094 // Two choices to find the correct ModuleEntry:
3095 // 1. If hidden class is within a nest, use nest host's module
3096 // 2. Find the unnamed module off from the class loader
3097 // For now option #2 is used since a nest host is not set until
3098 // after the instance class is created in jvm_lookup_define_class().
3099 if (class_loader_data()->is_boot_class_loader_data()) {
3100 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3101 } else {
3102 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3103 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3104 return java_lang_Module::module_entry(module);
3105 }
3106 }
3107
3108 // Class is in a named package
3109 if (!in_unnamed_package()) {
3110 return _package_entry->module();
3111 }
3112
3113 // Class is in an unnamed package, return its loader's unnamed module
3114 return class_loader_data()->unnamed_module();
3115 }
3116
3117 bool InstanceKlass::in_javabase_module() const {
3118 return module()->name() == vmSymbols::java_base();
3119 }
3120
3121 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3122
3123 // ensure java/ packages only loaded by boot or platform builtin loaders
3124 // not needed for shared class since CDS does not archive prohibited classes.
3125 if (!in_aot_cache()) {
3126 check_prohibited_package(name(), loader_data, CHECK);
3127 }
3128
3129 if (in_aot_cache() && _package_entry != nullptr) {
3130 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3131 // we can use the saved package
3132 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3133 return;
3134 } else {
3135 _package_entry = nullptr;
3136 }
3137 }
3138
3139 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3140 // it returns, so we need to decrement it when the current function exits.
3141 TempNewSymbol from_class_name =
3142 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3143
3144 Symbol* pkg_name;
3145 if (pkg_entry != nullptr) {
3146 pkg_name = pkg_entry->name();
3147 } else {
3148 pkg_name = from_class_name;
3149 }
3150
3151 if (pkg_name != nullptr && loader_data != nullptr) {
3152
3153 // Find in class loader's package entry table.
3154 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3155
3156 // If the package name is not found in the loader's package
3157 // entry table, it is an indication that the package has not
3158 // been defined. Consider it defined within the unnamed module.
3159 if (_package_entry == nullptr) {
3160
3161 if (!ModuleEntryTable::javabase_defined()) {
3162 // Before java.base is defined during bootstrapping, define all packages in
3163 // the java.base module. If a non-java.base package is erroneously placed
3164 // in the java.base module it will be caught later when java.base
3165 // is defined by ModuleEntryTable::verify_javabase_packages check.
3166 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3167 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3168 } else {
3169 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3170 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3171 }
3172
3173 // A package should have been successfully created
3174 DEBUG_ONLY(ResourceMark rm(THREAD));
3175 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3176 name()->as_C_string(), loader_data->loader_name_and_id());
3177 }
3178
3179 if (log_is_enabled(Debug, module)) {
3180 ResourceMark rm(THREAD);
3181 ModuleEntry* m = _package_entry->module();
3182 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3183 external_name(),
3184 pkg_name->as_C_string(),
3185 loader_data->loader_name_and_id(),
3186 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3187 }
3188 } else {
3189 ResourceMark rm(THREAD);
3190 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3191 external_name(),
3192 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3193 UNNAMED_MODULE);
3194 }
3195 }
3196
3197 // Function set_classpath_index ensures that for a non-null _package_entry
3198 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3199 // It then sets the classpath_index in the package entry record.
3200 //
3201 // The classpath_index field is used to find the entry on the boot loader class
3202 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3203 // in an unnamed module. It is also used to indicate (for all packages whose
3204 // classes are loaded by the boot loader) that at least one of the package's
3205 // classes has been loaded.
3206 void InstanceKlass::set_classpath_index(s2 path_index) {
3207 if (_package_entry != nullptr) {
3208 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3209 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3210 assert(path_index != -1, "Unexpected classpath_index");
3211 _package_entry->set_classpath_index(path_index);
3212 }
3213 }
3214
3215 // different versions of is_same_class_package
3216
3217 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3218 oop classloader1 = this->class_loader();
3219 PackageEntry* classpkg1 = this->package();
3220 if (class2->is_objArray_klass()) {
3221 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3222 }
3223
3224 oop classloader2;
3225 PackageEntry* classpkg2;
3226 if (class2->is_instance_klass()) {
3227 classloader2 = class2->class_loader();
3228 classpkg2 = class2->package();
3229 } else {
3230 assert(class2->is_typeArray_klass(), "should be type array");
3231 classloader2 = nullptr;
3232 classpkg2 = nullptr;
3233 }
3234
3235 // Same package is determined by comparing class loader
3236 // and package entries. Both must be the same. This rule
3237 // applies even to classes that are defined in the unnamed
3238 // package, they still must have the same class loader.
3239 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3240 return true;
3241 }
3242
3243 return false;
3244 }
3245
3246 // return true if this class and other_class are in the same package. Classloader
3247 // and classname information is enough to determine a class's package
3248 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3249 const Symbol* other_class_name) const {
3250 if (class_loader() != other_class_loader) {
3251 return false;
3252 }
3253 if (name()->fast_compare(other_class_name) == 0) {
3254 return true;
3255 }
3256
3257 {
3258 ResourceMark rm;
3259
3260 bool bad_class_name = false;
3261 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3262 if (bad_class_name) {
3263 return false;
3264 }
3265 // Check that package_from_class_name() returns null, not "", if there is no package.
3266 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3267
3268 const Symbol* const this_package_name =
3269 this->package() != nullptr ? this->package()->name() : nullptr;
3270
3271 if (this_package_name == nullptr || other_pkg == nullptr) {
3272 // One of the two doesn't have a package. Only return true if the other
3273 // one also doesn't have a package.
3274 return this_package_name == other_pkg;
3275 }
3276
3277 // Check if package is identical
3278 return this_package_name->fast_compare(other_pkg) == 0;
3279 }
3280 }
3281
3282 static bool is_prohibited_package_slow(Symbol* class_name) {
3283 // Caller has ResourceMark
3284 int length;
3285 jchar* unicode = class_name->as_unicode(length);
3286 return (length >= 5 &&
3287 unicode[0] == 'j' &&
3288 unicode[1] == 'a' &&
3289 unicode[2] == 'v' &&
3290 unicode[3] == 'a' &&
3291 unicode[4] == '/');
3292 }
3293
3294 // Only boot and platform class loaders can define classes in "java/" packages.
3295 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3296 ClassLoaderData* loader_data,
3297 TRAPS) {
3298 if (!loader_data->is_boot_class_loader_data() &&
3299 !loader_data->is_platform_class_loader_data() &&
3300 class_name != nullptr && class_name->utf8_length() >= 5) {
3301 ResourceMark rm(THREAD);
3302 bool prohibited;
3303 const u1* base = class_name->base();
3304 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3305 prohibited = is_prohibited_package_slow(class_name);
3306 } else {
3307 char* name = class_name->as_C_string();
3308 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3309 }
3310 if (prohibited) {
3311 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3312 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3313 char* name = pkg_name->as_C_string();
3314 const char* class_loader_name = loader_data->loader_name_and_id();
3315 StringUtils::replace_no_expand(name, "/", ".");
3316 const char* msg_text1 = "Class loader (instance of): ";
3317 const char* msg_text2 = " tried to load prohibited package name: ";
3318 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3319 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3320 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3321 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3322 }
3323 }
3324 return;
3325 }
3326
3327 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3328 constantPoolHandle i_cp(THREAD, constants());
3329 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3330 int ioff = iter.inner_class_info_index();
3331 if (ioff != 0) {
3332 // Check to see if the name matches the class we're looking for
3333 // before attempting to find the class.
3334 if (i_cp->klass_name_at_matches(this, ioff)) {
3335 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3336 if (this == inner_klass) {
3337 *ooff = iter.outer_class_info_index();
3338 *noff = iter.inner_name_index();
3339 return true;
3340 }
3341 }
3342 }
3343 }
3344 return false;
3345 }
3346
3347 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3348 InstanceKlass* outer_klass = nullptr;
3349 *inner_is_member = false;
3350 int ooff = 0, noff = 0;
3351 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3352 if (has_inner_classes_attr) {
3353 constantPoolHandle i_cp(THREAD, constants());
3354 if (ooff != 0) {
3355 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3356 if (!ok->is_instance_klass()) {
3357 // If the outer class is not an instance klass then it cannot have
3358 // declared any inner classes.
3359 ResourceMark rm(THREAD);
3360 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3361 Exceptions::fthrow(
3362 THREAD_AND_LOCATION,
3363 vmSymbols::java_lang_IncompatibleClassChangeError(),
3364 "%s and %s disagree on InnerClasses attribute",
3365 ok->external_name(),
3366 external_name());
3367 return nullptr;
3368 }
3369 outer_klass = InstanceKlass::cast(ok);
3370 *inner_is_member = true;
3371 }
3372 if (nullptr == outer_klass) {
3373 // It may be a local class; try for that.
3374 int encl_method_class_idx = enclosing_method_class_index();
3375 if (encl_method_class_idx != 0) {
3376 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3377 outer_klass = InstanceKlass::cast(ok);
3378 *inner_is_member = false;
3379 }
3380 }
3381 }
3382
3383 // If no inner class attribute found for this class.
3384 if (nullptr == outer_klass) return nullptr;
3385
3386 // Throws an exception if outer klass has not declared k as an inner klass
3387 // We need evidence that each klass knows about the other, or else
3388 // the system could allow a spoof of an inner class to gain access rights.
3389 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3390 return outer_klass;
3391 }
3392
3393 u2 InstanceKlass::compute_modifier_flags() const {
3394 u2 access = access_flags().as_unsigned_short();
3395
3396 // But check if it happens to be member class.
3397 InnerClassesIterator iter(this);
3398 for (; !iter.done(); iter.next()) {
3399 int ioff = iter.inner_class_info_index();
3400 // Inner class attribute can be zero, skip it.
3401 // Strange but true: JVM spec. allows null inner class refs.
3402 if (ioff == 0) continue;
3403
3404 // only look at classes that are already loaded
3405 // since we are looking for the flags for our self.
3406 Symbol* inner_name = constants()->klass_name_at(ioff);
3407 if (name() == inner_name) {
3408 // This is really a member class.
3409 access = iter.inner_access_flags();
3410 break;
3411 }
3412 }
3413 // Remember to strip ACC_SUPER bit
3414 return (access & (~JVM_ACC_SUPER));
3415 }
3416
3417 jint InstanceKlass::jvmti_class_status() const {
3418 jint result = 0;
3419
3420 if (is_linked()) {
3421 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3422 }
3423
3424 if (is_initialized()) {
3425 assert(is_linked(), "Class status is not consistent");
3426 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3427 }
3428 if (is_in_error_state()) {
3429 result |= JVMTI_CLASS_STATUS_ERROR;
3430 }
3431 return result;
3432 }
3433
3434 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3435 bool implements_interface; // initialized by method_at_itable_or_null
3436 Method* m = method_at_itable_or_null(holder, index,
3437 implements_interface); // out parameter
3438 if (m != nullptr) {
3439 assert(implements_interface, "sanity");
3440 return m;
3441 } else if (implements_interface) {
3442 // Throw AbstractMethodError since corresponding itable slot is empty.
3443 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3444 } else {
3445 // If the interface isn't implemented by the receiver class,
3446 // the VM should throw IncompatibleClassChangeError.
3447 ResourceMark rm(THREAD);
3448 stringStream ss;
3449 bool same_module = (module() == holder->module());
3450 ss.print("Receiver class %s does not implement "
3451 "the interface %s defining the method to be called "
3452 "(%s%s%s)",
3453 external_name(), holder->external_name(),
3454 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3455 (same_module) ? "" : "; ",
3456 (same_module) ? "" : holder->class_in_module_of_loader());
3457 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3458 }
3459 }
3460
3461 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3462 klassItable itable(this);
3463 for (int i = 0; i < itable.size_offset_table(); i++) {
3464 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3465 if (offset_entry->interface_klass() == holder) {
3466 implements_interface = true;
3467 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3468 Method* m = ime[index].method();
3469 return m;
3470 }
3471 }
3472 implements_interface = false;
3473 return nullptr; // offset entry not found
3474 }
3475
3476 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3477 assert(is_linked(), "required");
3478 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3479 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3480
3481 int vtable_index = Method::invalid_vtable_index;
3482 Symbol* name = intf_method->name();
3483 Symbol* signature = intf_method->signature();
3484
3485 // First check in default method array
3486 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3487 int index = find_method_index(default_methods(),
3488 name, signature,
3489 Klass::OverpassLookupMode::find,
3490 Klass::StaticLookupMode::find,
3491 Klass::PrivateLookupMode::find);
3492 if (index >= 0) {
3493 vtable_index = default_vtable_indices()->at(index);
3494 }
3495 }
3496 if (vtable_index == Method::invalid_vtable_index) {
3497 // get vtable_index for miranda methods
3498 klassVtable vt = vtable();
3499 vtable_index = vt.index_of_miranda(name, signature);
3500 }
3501 return vtable_index;
3502 }
3503
3504 #if INCLUDE_JVMTI
3505 // update default_methods for redefineclasses for methods that are
3506 // not yet in the vtable due to concurrent subclass define and superinterface
3507 // redefinition
3508 // Note: those in the vtable, should have been updated via adjust_method_entries
3509 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3510 // search the default_methods for uses of either obsolete or EMCP methods
3511 if (default_methods() != nullptr) {
3512 for (int index = 0; index < default_methods()->length(); index ++) {
3513 Method* old_method = default_methods()->at(index);
3514 if (old_method == nullptr || !old_method->is_old()) {
3515 continue; // skip uninteresting entries
3516 }
3517 assert(!old_method->is_deleted(), "default methods may not be deleted");
3518 Method* new_method = old_method->get_new_method();
3519 default_methods()->at_put(index, new_method);
3520
3521 if (log_is_enabled(Info, redefine, class, update)) {
3522 ResourceMark rm;
3523 if (!(*trace_name_printed)) {
3524 log_info(redefine, class, update)
3525 ("adjust: klassname=%s default methods from name=%s",
3526 external_name(), old_method->method_holder()->external_name());
3527 *trace_name_printed = true;
3528 }
3529 log_debug(redefine, class, update, vtables)
3530 ("default method update: %s(%s) ",
3531 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3532 }
3533 }
3534 }
3535 }
3536 #endif // INCLUDE_JVMTI
3537
3538 // On-stack replacement stuff
3539 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3540 assert_lock_strong(NMethodState_lock);
3541 #ifndef PRODUCT
3542 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3543 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3544 "redundant OSR recompilation detected. memory leak in CodeCache!");
3545 #endif
3546 // only one compilation can be active
3547 assert(n->is_osr_method(), "wrong kind of nmethod");
3548 n->set_osr_link(osr_nmethods_head());
3549 set_osr_nmethods_head(n);
3550 // Raise the highest osr level if necessary
3551 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3552
3553 // Get rid of the osr methods for the same bci that have lower levels.
3554 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3555 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3556 if (inv != nullptr && inv->is_in_use()) {
3557 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3558 }
3559 }
3560 }
3561
3562 // Remove osr nmethod from the list. Return true if found and removed.
3563 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3564 // This is a short non-blocking critical region, so the no safepoint check is ok.
3565 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3566 assert(n->is_osr_method(), "wrong kind of nmethod");
3567 nmethod* last = nullptr;
3568 nmethod* cur = osr_nmethods_head();
3569 int max_level = CompLevel_none; // Find the max comp level excluding n
3570 Method* m = n->method();
3571 // Search for match
3572 bool found = false;
3573 while(cur != nullptr && cur != n) {
3574 if (m == cur->method()) {
3575 // Find max level before n
3576 max_level = MAX2(max_level, cur->comp_level());
3577 }
3578 last = cur;
3579 cur = cur->osr_link();
3580 }
3581 nmethod* next = nullptr;
3582 if (cur == n) {
3583 found = true;
3584 next = cur->osr_link();
3585 if (last == nullptr) {
3586 // Remove first element
3587 set_osr_nmethods_head(next);
3588 } else {
3589 last->set_osr_link(next);
3590 }
3591 }
3592 n->set_osr_link(nullptr);
3593 cur = next;
3594 while (cur != nullptr) {
3595 // Find max level after n
3596 if (m == cur->method()) {
3597 max_level = MAX2(max_level, cur->comp_level());
3598 }
3599 cur = cur->osr_link();
3600 }
3601 m->set_highest_osr_comp_level(max_level);
3602 return found;
3603 }
3604
3605 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3606 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3607 nmethod* osr = osr_nmethods_head();
3608 int found = 0;
3609 while (osr != nullptr) {
3610 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3611 if (osr->method() == m) {
3612 deopt_scope->mark(osr);
3613 found++;
3614 }
3615 osr = osr->osr_link();
3616 }
3617 return found;
3618 }
3619
3620 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3621 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3622 nmethod* osr = osr_nmethods_head();
3623 nmethod* best = nullptr;
3624 while (osr != nullptr) {
3625 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3626 // There can be a time when a c1 osr method exists but we are waiting
3627 // for a c2 version. When c2 completes its osr nmethod we will trash
3628 // the c1 version and only be able to find the c2 version. However
3629 // while we overflow in the c1 code at back branches we don't want to
3630 // try and switch to the same code as we are already running
3631
3632 if (osr->method() == m &&
3633 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3634 if (match_level) {
3635 if (osr->comp_level() == comp_level) {
3636 // Found a match - return it.
3637 return osr;
3638 }
3639 } else {
3640 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3641 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3642 // Found the best possible - return it.
3643 return osr;
3644 }
3645 best = osr;
3646 }
3647 }
3648 }
3649 osr = osr->osr_link();
3650 }
3651
3652 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3653 if (best != nullptr && best->comp_level() >= comp_level) {
3654 return best;
3655 }
3656 return nullptr;
3657 }
3658
3659 // -----------------------------------------------------------------------------------------------------
3660 // Printing
3661
3662 #define BULLET " - "
3663
3664 static const char* state_names[] = {
3665 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3666 };
3667
3668 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3669 for (int i = 0; i < len; i++) {
3670 intptr_t e = start[i];
3671 st->print("%d : " INTPTR_FORMAT, i, e);
3672 if (MetaspaceObj::is_valid((Metadata*)e)) {
3673 st->print(" ");
3674 ((Metadata*)e)->print_value_on(st);
3675 }
3676 st->cr();
3677 }
3678 }
3679
3680 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3681 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3682 }
3683
3684 const char* InstanceKlass::init_state_name() const {
3685 return state_names[init_state()];
3686 }
3687
3688 void InstanceKlass::print_on(outputStream* st) const {
3689 assert(is_klass(), "must be klass");
3690 Klass::print_on(st);
3691
3692 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3693 st->print(BULLET"klass size: %d", size()); st->cr();
3694 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3695 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3696 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3697 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3698 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3699 st->print(BULLET"sub: ");
3700 Klass* sub = subklass();
3701 int n;
3702 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3703 if (n < MaxSubklassPrintSize) {
3704 sub->print_value_on(st);
3705 st->print(" ");
3706 }
3707 }
3708 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3709 st->cr();
3710
3711 if (is_interface()) {
3712 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3713 if (nof_implementors() == 1) {
3714 st->print_cr(BULLET"implementor: ");
3715 st->print(" ");
3716 implementor()->print_value_on(st);
3717 st->cr();
3718 }
3719 }
3720
3721 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3722 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3723 if (Verbose || WizardMode) {
3724 Array<Method*>* method_array = methods();
3725 for (int i = 0; i < method_array->length(); i++) {
3726 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3727 }
3728 }
3729 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3730 if (default_methods() != nullptr) {
3731 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3732 if (Verbose) {
3733 Array<Method*>* method_array = default_methods();
3734 for (int i = 0; i < method_array->length(); i++) {
3735 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3736 }
3737 }
3738 }
3739 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3740 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3741 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3742
3743 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3744
3745 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3746 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3747
3748 if (secondary_supers() != nullptr) {
3749 if (Verbose) {
3750 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3751 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3752 for (int i = 0; i < _secondary_supers->length(); i++) {
3753 ResourceMark rm; // for external_name()
3754 Klass* secondary_super = _secondary_supers->at(i);
3755 st->print(BULLET"%2d:", i);
3756 if (is_hashed) {
3757 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3758 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3759 st->print(" dist:%02d:", distance);
3760 }
3761 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3762 }
3763 }
3764 }
3765 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3766
3767 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3768 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3769 if (source_debug_extension() != nullptr) {
3770 st->print(BULLET"source debug extension: ");
3771 st->print("%s", source_debug_extension());
3772 st->cr();
3773 }
3774 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3775 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3776 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3777 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3778 {
3779 bool have_pv = false;
3780 // previous versions are linked together through the InstanceKlass
3781 for (InstanceKlass* pv_node = previous_versions();
3782 pv_node != nullptr;
3783 pv_node = pv_node->previous_versions()) {
3784 if (!have_pv)
3785 st->print(BULLET"previous version: ");
3786 have_pv = true;
3787 pv_node->constants()->print_value_on(st);
3788 }
3789 if (have_pv) st->cr();
3790 }
3791
3792 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3793 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3794 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3795 print_on_maybe_null(st, BULLET"record components: ", record_components());
3796 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3797 if (java_mirror() != nullptr) {
3798 st->print(BULLET"java mirror: ");
3799 java_mirror()->print_value_on(st);
3800 st->cr();
3801 } else {
3802 st->print_cr(BULLET"java mirror: null");
3803 }
3804 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3805 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3806 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3807 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3808 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3809
3810 FieldPrinter print_static_field(st);
3811 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3812 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3813 FieldPrinter print_nonstatic_field(st);
3814 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3815 ik->print_nonstatic_fields(&print_nonstatic_field);
3816
3817 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3818 OopMapBlock* map = start_of_nonstatic_oop_maps();
3819 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3820 while (map < end_map) {
3821 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3822 map++;
3823 }
3824 st->cr();
3825
3826 if (fieldinfo_search_table() != nullptr) {
3827 st->print_cr(BULLET"---- field info search table:");
3828 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
3829 }
3830 }
3831
3832 void InstanceKlass::print_value_on(outputStream* st) const {
3833 assert(is_klass(), "must be klass");
3834 if (Verbose || WizardMode) access_flags().print_on(st);
3835 name()->print_value_on(st);
3836 }
3837
3838 void FieldPrinter::do_field(fieldDescriptor* fd) {
3839 _st->print(BULLET);
3840 if (_obj == nullptr) {
3841 fd->print_on(_st);
3842 _st->cr();
3843 } else {
3844 fd->print_on_for(_st, _obj);
3845 _st->cr();
3846 }
3847 }
3848
3849
3850 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3851 Klass::oop_print_on(obj, st);
3852
3853 if (this == vmClasses::String_klass()) {
3854 typeArrayOop value = java_lang_String::value(obj);
3855 juint length = java_lang_String::length(obj);
3856 if (value != nullptr &&
3857 value->is_typeArray() &&
3858 length <= (juint) value->length()) {
3859 st->print(BULLET"string: ");
3860 java_lang_String::print(obj, st);
3861 st->cr();
3862 }
3863 }
3864
3865 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3866 FieldPrinter print_field(st, obj);
3867 print_nonstatic_fields(&print_field);
3868
3869 if (this == vmClasses::Class_klass()) {
3870 st->print(BULLET"signature: ");
3871 java_lang_Class::print_signature(obj, st);
3872 st->cr();
3873 Klass* real_klass = java_lang_Class::as_Klass(obj);
3874 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3875 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3876 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3877 }
3878 } else if (this == vmClasses::MethodType_klass()) {
3879 st->print(BULLET"signature: ");
3880 java_lang_invoke_MethodType::print_signature(obj, st);
3881 st->cr();
3882 }
3883 }
3884
3885 #ifndef PRODUCT
3886
3887 bool InstanceKlass::verify_itable_index(int i) {
3888 int method_count = klassItable::method_count_for_interface(this);
3889 assert(i >= 0 && i < method_count, "index out of bounds");
3890 return true;
3891 }
3892
3893 #endif //PRODUCT
3894
3895 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3896 st->print("a ");
3897 name()->print_value_on(st);
3898 obj->print_address_on(st);
3899 if (this == vmClasses::String_klass()
3900 && java_lang_String::value(obj) != nullptr) {
3901 ResourceMark rm;
3902 int len = java_lang_String::length(obj);
3903 int plen = (len < 24 ? len : 12);
3904 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3905 st->print(" = \"%s\"", str);
3906 if (len > plen)
3907 st->print("...[%d]", len);
3908 } else if (this == vmClasses::Class_klass()) {
3909 Klass* k = java_lang_Class::as_Klass(obj);
3910 st->print(" = ");
3911 if (k != nullptr) {
3912 k->print_value_on(st);
3913 } else {
3914 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3915 st->print("%s", tname ? tname : "type?");
3916 }
3917 } else if (this == vmClasses::MethodType_klass()) {
3918 st->print(" = ");
3919 java_lang_invoke_MethodType::print_signature(obj, st);
3920 } else if (java_lang_boxing_object::is_instance(obj)) {
3921 st->print(" = ");
3922 java_lang_boxing_object::print(obj, st);
3923 } else if (this == vmClasses::LambdaForm_klass()) {
3924 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3925 if (vmentry != nullptr) {
3926 st->print(" => ");
3927 vmentry->print_value_on(st);
3928 }
3929 } else if (this == vmClasses::MemberName_klass()) {
3930 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3931 if (vmtarget != nullptr) {
3932 st->print(" = ");
3933 vmtarget->print_value_on(st);
3934 } else {
3935 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3936 oop name = java_lang_invoke_MemberName::name(obj);
3937 if (clazz != nullptr) {
3938 clazz->print_value_on(st);
3939 } else {
3940 st->print("null");
3941 }
3942 st->print(".");
3943 if (name != nullptr) {
3944 name->print_value_on(st);
3945 } else {
3946 st->print("null");
3947 }
3948 }
3949 }
3950 }
3951
3952 const char* InstanceKlass::internal_name() const {
3953 return external_name();
3954 }
3955
3956 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3957 const ModuleEntry* module_entry,
3958 const ClassFileStream* cfs) const {
3959
3960 if (ClassListWriter::is_enabled()) {
3961 ClassListWriter::write(this, cfs);
3962 }
3963
3964 print_class_load_helper(loader_data, module_entry, cfs);
3965 print_class_load_cause_logging();
3966 }
3967
3968 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3969 const ModuleEntry* module_entry,
3970 const ClassFileStream* cfs) const {
3971
3972 if (!log_is_enabled(Info, class, load)) {
3973 return;
3974 }
3975
3976 ResourceMark rm;
3977 LogMessage(class, load) msg;
3978 stringStream info_stream;
3979
3980 // Name and class hierarchy info
3981 info_stream.print("%s", external_name());
3982
3983 // Source
3984 if (cfs != nullptr) {
3985 if (cfs->source() != nullptr) {
3986 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3987 if (module_name != nullptr) {
3988 // When the boot loader created the stream, it didn't know the module name
3989 // yet. Let's format it now.
3990 if (cfs->from_boot_loader_modules_image()) {
3991 info_stream.print(" source: jrt:/%s", module_name);
3992 } else {
3993 info_stream.print(" source: %s", cfs->source());
3994 }
3995 } else {
3996 info_stream.print(" source: %s", cfs->source());
3997 }
3998 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3999 Thread* current = Thread::current();
4000 Klass* caller = current->is_Java_thread() ?
4001 JavaThread::cast(current)->security_get_caller_class(1):
4002 nullptr;
4003 // caller can be null, for example, during a JVMTI VM_Init hook
4004 if (caller != nullptr) {
4005 info_stream.print(" source: instance of %s", caller->external_name());
4006 } else {
4007 // source is unknown
4008 }
4009 } else {
4010 oop class_loader = loader_data->class_loader();
4011 info_stream.print(" source: %s", class_loader->klass()->external_name());
4012 }
4013 } else {
4014 assert(this->in_aot_cache(), "must be");
4015 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
4016 info_stream.print(" source: shared objects file (top)");
4017 } else {
4018 info_stream.print(" source: shared objects file");
4019 }
4020 }
4021
4022 msg.info("%s", info_stream.as_string());
4023
4024 if (log_is_enabled(Debug, class, load)) {
4025 stringStream debug_stream;
4026
4027 // Class hierarchy info
4028 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4029 p2i(this), p2i(super()));
4030
4031 // Interfaces
4032 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4033 debug_stream.print(" interfaces:");
4034 int length = local_interfaces()->length();
4035 for (int i = 0; i < length; i++) {
4036 debug_stream.print(" " PTR_FORMAT,
4037 p2i(local_interfaces()->at(i)));
4038 }
4039 }
4040
4041 // Class loader
4042 debug_stream.print(" loader: [");
4043 loader_data->print_value_on(&debug_stream);
4044 debug_stream.print("]");
4045
4046 // Classfile checksum
4047 if (cfs) {
4048 debug_stream.print(" bytes: %d checksum: %08x",
4049 cfs->length(),
4050 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4051 cfs->length()));
4052 }
4053
4054 msg.debug("%s", debug_stream.as_string());
4055 }
4056 }
4057
4058 void InstanceKlass::print_class_load_cause_logging() const {
4059 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4060 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4061 JavaThread* current = JavaThread::current();
4062 ResourceMark rm(current);
4063 const char* name = external_name();
4064
4065 if (LogClassLoadingCauseFor == nullptr ||
4066 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4067 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4068 return;
4069 }
4070
4071 // Log Java stack first
4072 {
4073 LogMessage(class, load, cause) msg;
4074 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4075
4076 info_stream.print_cr("Java stack when loading %s:", name);
4077 current->print_stack_on(&info_stream);
4078 }
4079
4080 // Log native stack second
4081 if (log_cause_native) {
4082 // Log to string first so that lines can be indented
4083 stringStream stack_stream;
4084 char buf[O_BUFLEN];
4085 address lastpc = nullptr;
4086 NativeStackPrinter nsp(current);
4087 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4088 true /* print_source_info */, -1 /* max stack */);
4089
4090 LogMessage(class, load, cause, native) msg;
4091 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4092 info_stream.print_cr("Native stack when loading %s:", name);
4093
4094 // Print each native stack line to the log
4095 int size = (int) stack_stream.size();
4096 char* stack = stack_stream.as_string();
4097 char* stack_end = stack + size;
4098 char* line_start = stack;
4099 for (char* p = stack; p < stack_end; p++) {
4100 if (*p == '\n') {
4101 *p = '\0';
4102 info_stream.print_cr("\t%s", line_start);
4103 line_start = p + 1;
4104 }
4105 }
4106 if (line_start < stack_end) {
4107 info_stream.print_cr("\t%s", line_start);
4108 }
4109 }
4110 }
4111 }
4112
4113 // Verification
4114
4115 class VerifyFieldClosure: public BasicOopIterateClosure {
4116 protected:
4117 template <class T> void do_oop_work(T* p) {
4118 oop obj = RawAccess<>::oop_load(p);
4119 if (!oopDesc::is_oop_or_null(obj)) {
4120 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4121 Universe::print_on(tty);
4122 guarantee(false, "boom");
4123 }
4124 }
4125 public:
4126 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4127 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4128 };
4129
4130 void InstanceKlass::verify_on(outputStream* st) {
4131 #ifndef PRODUCT
4132 // Avoid redundant verifies, this really should be in product.
4133 if (_verify_count == Universe::verify_count()) return;
4134 _verify_count = Universe::verify_count();
4135 #endif
4136
4137 // Verify Klass
4138 Klass::verify_on(st);
4139
4140 // Verify that klass is present in ClassLoaderData
4141 guarantee(class_loader_data()->contains_klass(this),
4142 "this class isn't found in class loader data");
4143
4144 // Verify vtables
4145 if (is_linked()) {
4146 // $$$ This used to be done only for m/s collections. Doing it
4147 // always seemed a valid generalization. (DLD -- 6/00)
4148 vtable().verify(st);
4149 }
4150
4151 // Verify first subklass
4152 if (subklass() != nullptr) {
4153 guarantee(subklass()->is_klass(), "should be klass");
4154 }
4155
4156 // Verify siblings
4157 Klass* super = this->super();
4158 Klass* sib = next_sibling();
4159 if (sib != nullptr) {
4160 if (sib == this) {
4161 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4162 }
4163
4164 guarantee(sib->is_klass(), "should be klass");
4165 guarantee(sib->super() == super, "siblings should have same superklass");
4166 }
4167
4168 // Verify local interfaces
4169 if (local_interfaces()) {
4170 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4171 for (int j = 0; j < local_interfaces->length(); j++) {
4172 InstanceKlass* e = local_interfaces->at(j);
4173 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4174 }
4175 }
4176
4177 // Verify transitive interfaces
4178 if (transitive_interfaces() != nullptr) {
4179 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4180 for (int j = 0; j < transitive_interfaces->length(); j++) {
4181 InstanceKlass* e = transitive_interfaces->at(j);
4182 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4183 }
4184 }
4185
4186 // Verify methods
4187 if (methods() != nullptr) {
4188 Array<Method*>* methods = this->methods();
4189 for (int j = 0; j < methods->length(); j++) {
4190 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4191 }
4192 for (int j = 0; j < methods->length() - 1; j++) {
4193 Method* m1 = methods->at(j);
4194 Method* m2 = methods->at(j + 1);
4195 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4196 }
4197 }
4198
4199 // Verify method ordering
4200 if (method_ordering() != nullptr) {
4201 Array<int>* method_ordering = this->method_ordering();
4202 int length = method_ordering->length();
4203 if (JvmtiExport::can_maintain_original_method_order() ||
4204 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4205 guarantee(length == methods()->length(), "invalid method ordering length");
4206 jlong sum = 0;
4207 for (int j = 0; j < length; j++) {
4208 int original_index = method_ordering->at(j);
4209 guarantee(original_index >= 0, "invalid method ordering index");
4210 guarantee(original_index < length, "invalid method ordering index");
4211 sum += original_index;
4212 }
4213 // Verify sum of indices 0,1,...,length-1
4214 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4215 } else {
4216 guarantee(length == 0, "invalid method ordering length");
4217 }
4218 }
4219
4220 // Verify default methods
4221 if (default_methods() != nullptr) {
4222 Array<Method*>* methods = this->default_methods();
4223 for (int j = 0; j < methods->length(); j++) {
4224 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4225 }
4226 for (int j = 0; j < methods->length() - 1; j++) {
4227 Method* m1 = methods->at(j);
4228 Method* m2 = methods->at(j + 1);
4229 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4230 }
4231 }
4232
4233 // Verify JNI static field identifiers
4234 if (jni_ids() != nullptr) {
4235 jni_ids()->verify(this);
4236 }
4237
4238 // Verify other fields
4239 if (constants() != nullptr) {
4240 guarantee(constants()->is_constantPool(), "should be constant pool");
4241 }
4242 }
4243
4244 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4245 Klass::oop_verify_on(obj, st);
4246 VerifyFieldClosure blk;
4247 obj->oop_iterate(&blk);
4248 }
4249
4250 // JNIid class for jfieldIDs only
4251 // Note to reviewers:
4252 // These JNI functions are just moved over to column 1 and not changed
4253 // in the compressed oops workspace.
4254 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4255 _holder = holder;
4256 _offset = offset;
4257 _next = next;
4258 DEBUG_ONLY(_is_static_field_id = false;)
4259 }
4260
4261 JNIid* JNIid::find(int offset) {
4262 JNIid* current = this;
4263 while (current != nullptr) {
4264 if (current->offset() == offset) return current;
4265 current = current->next();
4266 }
4267 return nullptr;
4268 }
4269
4270 void JNIid::deallocate(JNIid* current) {
4271 while (current != nullptr) {
4272 JNIid* next = current->next();
4273 delete current;
4274 current = next;
4275 }
4276 }
4277
4278 void JNIid::verify(InstanceKlass* holder) {
4279 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4280 int end_field_offset;
4281 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4282
4283 JNIid* current = this;
4284 while (current != nullptr) {
4285 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4286 #ifdef ASSERT
4287 int o = current->offset();
4288 if (current->is_static_field_id()) {
4289 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4290 }
4291 #endif
4292 current = current->next();
4293 }
4294 }
4295
4296 void InstanceKlass::set_init_state(ClassState state) {
4297 #ifdef ASSERT
4298 bool good_state = in_aot_cache() ? (_init_state <= state)
4299 : (_init_state < state);
4300 assert(good_state || state == allocated, "illegal state transition");
4301 #endif
4302 assert(_init_thread == nullptr, "should be cleared before state change");
4303 AtomicAccess::release_store(&_init_state, state);
4304 }
4305
4306 #if INCLUDE_JVMTI
4307
4308 // RedefineClasses() support for previous versions
4309
4310 // Globally, there is at least one previous version of a class to walk
4311 // during class unloading, which is saved because old methods in the class
4312 // are still running. Otherwise the previous version list is cleaned up.
4313 bool InstanceKlass::_should_clean_previous_versions = false;
4314
4315 // Returns true if there are previous versions of a class for class
4316 // unloading only. Also resets the flag to false. purge_previous_version
4317 // will set the flag to true if there are any left, i.e., if there's any
4318 // work to do for next time. This is to avoid the expensive code cache
4319 // walk in CLDG::clean_deallocate_lists().
4320 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4321 bool ret = _should_clean_previous_versions;
4322 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4323 ret ? "true" : "false");
4324 _should_clean_previous_versions = false;
4325 return ret;
4326 }
4327
4328 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4329 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4330 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4331 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4332 Array<Method*>* method_refs = klass->methods();
4333 for (int k = 0; k < method_refs->length(); k++) {
4334 Method* method = method_refs->at(k);
4335 // Only need to clear obsolete methods.
4336 if (method != nullptr && method->is_obsolete()) {
4337 method->clear_jmethod_id();
4338 }
4339 }
4340 }
4341
4342 // Purge previous versions before adding new previous versions of the class and
4343 // during class unloading.
4344 void InstanceKlass::purge_previous_version_list() {
4345 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4346 assert(has_been_redefined(), "Should only be called for main class");
4347
4348 // Quick exit.
4349 if (previous_versions() == nullptr) {
4350 return;
4351 }
4352
4353 // This klass has previous versions so see what we can cleanup
4354 // while it is safe to do so.
4355
4356 int deleted_count = 0; // leave debugging breadcrumbs
4357 int live_count = 0;
4358 ClassLoaderData* loader_data = class_loader_data();
4359 assert(loader_data != nullptr, "should never be null");
4360
4361 ResourceMark rm;
4362 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4363
4364 // previous versions are linked together through the InstanceKlass
4365 InstanceKlass* pv_node = previous_versions();
4366 InstanceKlass* last = this;
4367 int version = 0;
4368
4369 // check the previous versions list
4370 for (; pv_node != nullptr; ) {
4371
4372 ConstantPool* pvcp = pv_node->constants();
4373 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4374
4375 if (!pvcp->on_stack()) {
4376 // If the constant pool isn't on stack, none of the methods
4377 // are executing. Unlink this previous_version.
4378 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4379 // so will be deallocated during the next phase of class unloading.
4380 log_trace(redefine, class, iklass, purge)
4381 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4382 // Unlink from previous version list.
4383 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4384 InstanceKlass* next = pv_node->previous_versions();
4385 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4386 pv_node->link_previous_versions(nullptr); // point next to null
4387 last->link_previous_versions(next);
4388 // Delete this node directly. Nothing is referring to it and we don't
4389 // want it to increase the counter for metadata to delete in CLDG.
4390 MetadataFactory::free_metadata(loader_data, pv_node);
4391 pv_node = next;
4392 deleted_count++;
4393 version++;
4394 continue;
4395 } else {
4396 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4397 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4398 live_count++;
4399 if (pvcp->in_aot_cache()) {
4400 // Shared previous versions can never be removed so no cleaning is needed.
4401 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4402 } else {
4403 // Previous version alive, set that clean is needed for next time.
4404 _should_clean_previous_versions = true;
4405 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4406 }
4407 }
4408
4409 // next previous version
4410 last = pv_node;
4411 pv_node = pv_node->previous_versions();
4412 version++;
4413 }
4414 log_trace(redefine, class, iklass, purge)
4415 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4416 }
4417
4418 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4419 int emcp_method_count) {
4420 int obsolete_method_count = old_methods->length() - emcp_method_count;
4421
4422 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4423 _previous_versions != nullptr) {
4424 // We have a mix of obsolete and EMCP methods so we have to
4425 // clear out any matching EMCP method entries the hard way.
4426 int local_count = 0;
4427 for (int i = 0; i < old_methods->length(); i++) {
4428 Method* old_method = old_methods->at(i);
4429 if (old_method->is_obsolete()) {
4430 // only obsolete methods are interesting
4431 Symbol* m_name = old_method->name();
4432 Symbol* m_signature = old_method->signature();
4433
4434 // previous versions are linked together through the InstanceKlass
4435 int j = 0;
4436 for (InstanceKlass* prev_version = _previous_versions;
4437 prev_version != nullptr;
4438 prev_version = prev_version->previous_versions(), j++) {
4439
4440 Array<Method*>* method_refs = prev_version->methods();
4441 for (int k = 0; k < method_refs->length(); k++) {
4442 Method* method = method_refs->at(k);
4443
4444 if (!method->is_obsolete() &&
4445 method->name() == m_name &&
4446 method->signature() == m_signature) {
4447 // The current RedefineClasses() call has made all EMCP
4448 // versions of this method obsolete so mark it as obsolete
4449 log_trace(redefine, class, iklass, add)
4450 ("%s(%s): flush obsolete method @%d in version @%d",
4451 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4452
4453 method->set_is_obsolete();
4454 break;
4455 }
4456 }
4457
4458 // The previous loop may not find a matching EMCP method, but
4459 // that doesn't mean that we can optimize and not go any
4460 // further back in the PreviousVersion generations. The EMCP
4461 // method for this generation could have already been made obsolete,
4462 // but there still may be an older EMCP method that has not
4463 // been made obsolete.
4464 }
4465
4466 if (++local_count >= obsolete_method_count) {
4467 // no more obsolete methods so bail out now
4468 break;
4469 }
4470 }
4471 }
4472 }
4473 }
4474
4475 // Save the scratch_class as the previous version if any of the methods are running.
4476 // The previous_versions are used to set breakpoints in EMCP methods and they are
4477 // also used to clean MethodData links to redefined methods that are no longer running.
4478 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4479 int emcp_method_count) {
4480 assert(Thread::current()->is_VM_thread(),
4481 "only VMThread can add previous versions");
4482
4483 ResourceMark rm;
4484 log_trace(redefine, class, iklass, add)
4485 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4486
4487 // Clean out old previous versions for this class
4488 purge_previous_version_list();
4489
4490 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4491 // a previous redefinition may be made obsolete by this redefinition.
4492 Array<Method*>* old_methods = scratch_class->methods();
4493 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4494
4495 // If the constant pool for this previous version of the class
4496 // is not marked as being on the stack, then none of the methods
4497 // in this previous version of the class are on the stack so
4498 // we don't need to add this as a previous version.
4499 ConstantPool* cp_ref = scratch_class->constants();
4500 if (!cp_ref->on_stack()) {
4501 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4502 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4503 return;
4504 }
4505
4506 // Add previous version if any methods are still running or if this is
4507 // a shared class which should never be removed.
4508 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4509 scratch_class->link_previous_versions(previous_versions());
4510 link_previous_versions(scratch_class);
4511 if (cp_ref->in_aot_cache()) {
4512 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4513 } else {
4514 // We only set clean_previous_versions flag for processing during class
4515 // unloading for non-shared classes.
4516 _should_clean_previous_versions = true;
4517 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4518 }
4519 } // end add_previous_version()
4520
4521 #endif // INCLUDE_JVMTI
4522
4523 Method* InstanceKlass::method_with_idnum(int idnum) const {
4524 Method* m = nullptr;
4525 if (idnum < methods()->length()) {
4526 m = methods()->at(idnum);
4527 }
4528 if (m == nullptr || m->method_idnum() != idnum) {
4529 for (int index = 0; index < methods()->length(); ++index) {
4530 m = methods()->at(index);
4531 if (m->method_idnum() == idnum) {
4532 return m;
4533 }
4534 }
4535 // None found, return null for the caller to handle.
4536 return nullptr;
4537 }
4538 return m;
4539 }
4540
4541
4542 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4543 if (idnum >= methods()->length()) {
4544 return nullptr;
4545 }
4546 Method* m = methods()->at(idnum);
4547 if (m != nullptr && m->orig_method_idnum() == idnum) {
4548 return m;
4549 }
4550 // Obsolete method idnum does not match the original idnum
4551 for (int index = 0; index < methods()->length(); ++index) {
4552 m = methods()->at(index);
4553 if (m->orig_method_idnum() == idnum) {
4554 return m;
4555 }
4556 }
4557 // None found, return null for the caller to handle.
4558 return nullptr;
4559 }
4560
4561
4562 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4563 const InstanceKlass* holder = get_klass_version(version);
4564 if (holder == nullptr) {
4565 return nullptr; // The version of klass is gone, no method is found
4566 }
4567 return holder->method_with_orig_idnum(idnum);
4568 }
4569
4570 #if INCLUDE_JVMTI
4571 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4572 return _cached_class_file;
4573 }
4574
4575 jint InstanceKlass::get_cached_class_file_len() {
4576 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4577 }
4578
4579 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4580 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4581 }
4582 #endif
4583
4584 // Make a step iterating over the class hierarchy under the root class.
4585 // Skips subclasses if requested.
4586 void ClassHierarchyIterator::next() {
4587 assert(_current != nullptr, "required");
4588 if (_visit_subclasses && _current->subklass() != nullptr) {
4589 _current = _current->subklass();
4590 return; // visit next subclass
4591 }
4592 _visit_subclasses = true; // reset
4593 while (_current->next_sibling() == nullptr && _current != _root) {
4594 _current = _current->java_super(); // backtrack; no more sibling subclasses left
4595 }
4596 if (_current == _root) {
4597 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4598 _current = nullptr;
4599 return;
4600 }
4601 _current = _current->next_sibling();
4602 return; // visit next sibling subclass
4603 }