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/bytecodeHistogram.hpp"
49 #include "interpreter/bytecodeStream.hpp"
50 #include "interpreter/oopMapCache.hpp"
51 #include "interpreter/rewriter.hpp"
52 #include "jvm.h"
53 #include "jvmtifiles/jvmti.h"
54 #include "klass.inline.hpp"
55 #include "logging/log.hpp"
56 #include "logging/logMessage.hpp"
57 #include "logging/logStream.hpp"
58 #include "memory/allocation.inline.hpp"
59 #include "memory/iterator.inline.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceClosure.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "memory/universe.hpp"
65 #include "oops/constantPool.hpp"
66 #include "oops/fieldStreams.inline.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/atomicAccess.hpp"
83 #include "runtime/deoptimization.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/runtimeUpcalls.hpp"
93 #include "runtime/synchronizer.hpp"
94 #include "runtime/threads.hpp"
95 #include "services/classLoadingService.hpp"
96 #include "services/finalizerService.hpp"
97 #include "services/threadService.hpp"
98 #include "utilities/dtrace.hpp"
99 #include "utilities/events.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/nativeStackPrinter.hpp"
102 #include "utilities/stringUtils.hpp"
103 #ifdef COMPILER1
104 #include "c1/c1_Compiler.hpp"
105 #endif
106 #if INCLUDE_JFR
107 #include "jfr/jfrEvents.hpp"
108 #endif
109
110 #ifdef DTRACE_ENABLED
111
112
113 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
114 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
115 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
116 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
117 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
118 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
119 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
120 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
121 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
122 { \
123 char* data = nullptr; \
124 int len = 0; \
125 Symbol* clss_name = name(); \
126 if (clss_name != nullptr) { \
127 data = (char*)clss_name->bytes(); \
128 len = clss_name->utf8_length(); \
129 } \
130 HOTSPOT_CLASS_INITIALIZATION_##type( \
131 data, len, (void*)class_loader(), thread_type); \
132 }
133
134 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
135 { \
136 char* data = nullptr; \
137 int len = 0; \
138 Symbol* clss_name = name(); \
139 if (clss_name != nullptr) { \
140 data = (char*)clss_name->bytes(); \
141 len = clss_name->utf8_length(); \
142 } \
143 HOTSPOT_CLASS_INITIALIZATION_##type( \
144 data, len, (void*)class_loader(), thread_type, wait); \
145 }
146
147 #else // ndef DTRACE_ENABLED
148
149 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
150 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
151
152 #endif // ndef DTRACE_ENABLED
153
154 bool InstanceKlass::_finalization_enabled = true;
155
156 static inline bool is_class_loader(const Symbol* class_name,
157 const ClassFileParser& parser) {
158 assert(class_name != nullptr, "invariant");
159
160 if (class_name == vmSymbols::java_lang_ClassLoader()) {
161 return true;
162 }
163
164 if (vmClasses::ClassLoader_klass_is_loaded()) {
165 const Klass* const super_klass = parser.super_klass();
166 if (super_klass != nullptr) {
167 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
168 return true;
169 }
170 }
171 }
172 return false;
173 }
174
175 static inline bool is_stack_chunk_class(const Symbol* class_name,
176 const ClassLoaderData* loader_data) {
177 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
178 loader_data->is_the_null_class_loader_data());
179 }
180
181 // private: called to verify that k is a static member of this nest.
182 // We know that k is an instance class in the same package and hence the
183 // same classloader.
184 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
185 assert(!is_hidden(), "unexpected hidden class");
186 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
187 if (log_is_enabled(Trace, class, nestmates)) {
188 ResourceMark rm(current);
189 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
190 k->external_name(), this->external_name());
191 }
192 return false;
193 }
194
195 if (log_is_enabled(Trace, class, nestmates)) {
196 ResourceMark rm(current);
197 log_trace(class, nestmates)("Checking nest membership of %s in %s",
198 k->external_name(), this->external_name());
199 }
200
201 // Check for the named class in _nest_members.
202 // We don't resolve, or load, any classes.
203 for (int i = 0; i < _nest_members->length(); i++) {
204 int cp_index = _nest_members->at(i);
205 Symbol* name = _constants->klass_name_at(cp_index);
206 if (name == k->name()) {
207 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
208 return true;
209 }
210 }
211 log_trace(class, nestmates)("- class is NOT a nest member!");
212 return false;
213 }
214
215 // Called to verify that k is a permitted subclass of this class.
216 // The incoming stringStream is used to format the messages for error logging and for the caller
217 // to use for exception throwing.
218 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
219 Thread* current = Thread::current();
220 assert(k != nullptr, "sanity check");
221 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
222 "unexpected empty _permitted_subclasses array");
223
224 if (log_is_enabled(Trace, class, sealed)) {
225 ResourceMark rm(current);
226 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
227 k->external_name(), this->external_name());
228 }
229
230 // Check that the class and its super are in the same module.
231 if (k->module() != this->module()) {
232 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
233 "and sealed class %s is in module '%s' with loader %s",
234 k->external_name(),
235 k->module()->name_as_C_string(),
236 k->module()->loader_data()->loader_name_and_id(),
237 this->external_name(),
238 this->module()->name_as_C_string(),
239 this->module()->loader_data()->loader_name_and_id());
240 log_trace(class, sealed)(" - %s", ss.as_string());
241 return false;
242 }
243
244 if (!k->is_public() && !is_same_class_package(k)) {
245 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
246 "and sealed class %s is in package '%s' with classloader %s",
247 k->external_name(),
248 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
249 k->module()->loader_data()->loader_name_and_id(),
250 this->external_name(),
251 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
252 this->module()->loader_data()->loader_name_and_id());
253 log_trace(class, sealed)(" - %s", ss.as_string());
254 return false;
255 }
256
257 for (int i = 0; i < _permitted_subclasses->length(); i++) {
258 int cp_index = _permitted_subclasses->at(i);
259 Symbol* name = _constants->klass_name_at(cp_index);
260 if (name == k->name()) {
261 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
262 return true;
263 }
264 }
265
266 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
267 k->external_name(), this->external_name());
268 log_trace(class, sealed)(" - %s", ss.as_string());
269 return false;
270 }
271
272 // Return nest-host class, resolving, validating and saving it if needed.
273 // In cases where this is called from a thread that cannot do classloading
274 // (such as a native JIT thread) then we simply return null, which in turn
275 // causes the access check to return false. Such code will retry the access
276 // from a more suitable environment later. Otherwise the _nest_host is always
277 // set once this method returns.
278 // Any errors from nest-host resolution must be preserved so they can be queried
279 // from higher-level access checking code, and reported as part of access checking
280 // exceptions.
281 // VirtualMachineErrors are propagated with a null return.
282 // Under any conditions where the _nest_host can be set to non-null the resulting
283 // value of it and, if applicable, the nest host resolution/validation error,
284 // are idempotent.
285 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
286 InstanceKlass* nest_host_k = _nest_host;
287 if (nest_host_k != nullptr) {
288 return nest_host_k;
289 }
290
291 ResourceMark rm(THREAD);
292
293 // need to resolve and save our nest-host class.
294 if (_nest_host_index != 0) { // we have a real nest_host
295 // Before trying to resolve check if we're in a suitable context
296 bool can_resolve = THREAD->can_call_java();
297 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
298 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
299 this->external_name());
300 return nullptr; // sentinel to say "try again from a different context"
301 }
302
303 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
304 this->external_name(),
305 _constants->klass_name_at(_nest_host_index)->as_C_string());
306
307 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
308 if (HAS_PENDING_EXCEPTION) {
309 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
310 return nullptr; // propagate VMEs
311 }
312 stringStream ss;
313 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
314 ss.print("Nest host resolution of %s with host %s failed: ",
315 this->external_name(), target_host_class);
316 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
317 const char* msg = ss.as_string(true /* on C-heap */);
318 constantPoolHandle cph(THREAD, constants());
319 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
320 CLEAR_PENDING_EXCEPTION;
321
322 log_trace(class, nestmates)("%s", msg);
323 } else {
324 // A valid nest-host is an instance class in the current package that lists this
325 // class as a nest member. If any of these conditions are not met the class is
326 // its own nest-host.
327 const char* error = nullptr;
328
329 // JVMS 5.4.4 indicates package check comes first
330 if (is_same_class_package(k)) {
331 // Now check actual membership. We can't be a member if our "host" is
332 // not an instance class.
333 if (k->is_instance_klass()) {
334 nest_host_k = InstanceKlass::cast(k);
335 bool is_member = nest_host_k->has_nest_member(THREAD, this);
336 if (is_member) {
337 _nest_host = nest_host_k; // save resolved nest-host value
338
339 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
340 this->external_name(), k->external_name());
341 return nest_host_k;
342 } else {
343 error = "current type is not listed as a nest member";
344 }
345 } else {
346 error = "host is not an instance class";
347 }
348 } else {
349 error = "types are in different packages";
350 }
351
352 // something went wrong, so record what and log it
353 {
354 stringStream ss;
355 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
356 this->external_name(),
357 this->class_loader_data()->loader_name_and_id(),
358 k->external_name(),
359 k->class_loader_data()->loader_name_and_id(),
360 error);
361 const char* msg = ss.as_string(true /* on C-heap */);
362 constantPoolHandle cph(THREAD, constants());
363 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
364 log_trace(class, nestmates)("%s", msg);
365 }
366 }
367 } else {
368 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
369 this->external_name());
370 }
371
372 // Either not in an explicit nest, or else an error occurred, so
373 // the nest-host is set to `this`. Any thread that sees this assignment
374 // will also see any setting of nest_host_error(), if applicable.
375 return (_nest_host = this);
376 }
377
378 // Dynamic nest member support: set this class's nest host to the given class.
379 // This occurs as part of the class definition, as soon as the instanceKlass
380 // has been created and doesn't require further resolution. The code:
381 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
382 // results in:
383 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
384 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
385 // We also know the "host" is a valid nest-host in the same package so we can
386 // assert some of those facts.
387 void InstanceKlass::set_nest_host(InstanceKlass* host) {
388 assert(is_hidden(), "must be a hidden class");
389 assert(host != nullptr, "null nest host specified");
390 assert(_nest_host == nullptr, "current class has resolved nest-host");
391 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
392 nest_host_error());
393 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
394 (host->_nest_host == host), "proposed host is not a valid nest-host");
395 // Can't assert this as package is not set yet:
396 // assert(is_same_class_package(host), "proposed host is in wrong package");
397
398 if (log_is_enabled(Trace, class, nestmates)) {
399 ResourceMark rm;
400 const char* msg = "";
401 // a hidden class does not expect a statically defined nest-host
402 if (_nest_host_index > 0) {
403 msg = "(the NestHost attribute in the current class is ignored)";
404 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
405 msg = "(the NestMembers attribute in the current class is ignored)";
406 }
407 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
408 this->external_name(),
409 host->external_name(),
410 msg);
411 }
412 // set dynamic nest host
413 _nest_host = host;
414 // Record dependency to keep nest host from being unloaded before this class.
415 ClassLoaderData* this_key = class_loader_data();
416 assert(this_key != nullptr, "sanity");
417 this_key->record_dependency(host);
418 }
419
420 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
421 // or we are k's nest_host - all of which is covered by comparing the two
422 // resolved_nest_hosts.
423 // Any exceptions (i.e. VMEs) are propagated.
424 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
425
426 assert(this != k, "this should be handled by higher-level code");
427
428 // Per JVMS 5.4.4 we first resolve and validate the current class, then
429 // the target class k.
430
431 InstanceKlass* cur_host = nest_host(CHECK_false);
432 if (cur_host == nullptr) {
433 return false;
434 }
435
436 Klass* k_nest_host = k->nest_host(CHECK_false);
437 if (k_nest_host == nullptr) {
438 return false;
439 }
440
441 bool access = (cur_host == k_nest_host);
442
443 ResourceMark rm(THREAD);
444 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
445 this->external_name(),
446 access ? "" : "NOT ",
447 k->external_name());
448 return access;
449 }
450
451 const char* InstanceKlass::nest_host_error() {
452 if (_nest_host_index == 0) {
453 return nullptr;
454 } else {
455 constantPoolHandle cph(Thread::current(), constants());
456 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
457 }
458 }
459
460 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
461 const int size = InstanceKlass::size(parser.vtable_size(),
462 parser.itable_size(),
463 nonstatic_oop_map_size(parser.total_oop_map_count()),
464 parser.is_interface());
465
466 const Symbol* const class_name = parser.class_name();
467 assert(class_name != nullptr, "invariant");
468 ClassLoaderData* loader_data = parser.loader_data();
469 assert(loader_data != nullptr, "invariant");
470
471 InstanceKlass* ik;
472
473 // Allocation
474 if (parser.is_instance_ref_klass()) {
475 // java.lang.ref.Reference
476 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
477 } else if (class_name == vmSymbols::java_lang_Class()) {
478 // mirror - java.lang.Class
479 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
480 } else if (is_stack_chunk_class(class_name, loader_data)) {
481 // stack chunk
482 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
483 } else if (is_class_loader(class_name, parser)) {
484 // class loader - java.lang.ClassLoader
485 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
486 } else {
487 // normal
488 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
489 }
490
491 if (ik != nullptr && UseCompressedClassPointers) {
492 assert(CompressedKlassPointers::is_encodable(ik),
493 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
494 }
495
496 // Check for pending exception before adding to the loader data and incrementing
497 // class count. Can get OOM here.
498 if (HAS_PENDING_EXCEPTION) {
499 return nullptr;
500 }
501
502 return ik;
503 }
504
505
506 // copy method ordering from resource area to Metaspace
507 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
508 if (m != nullptr) {
509 // allocate a new array and copy contents (memcpy?)
510 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
511 for (int i = 0; i < m->length(); i++) {
512 _method_ordering->at_put(i, m->at(i));
513 }
514 } else {
515 _method_ordering = Universe::the_empty_int_array();
516 }
517 }
518
519 // create a new array of vtable_indices for default methods
520 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
521 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
522 assert(default_vtable_indices() == nullptr, "only create once");
523 set_default_vtable_indices(vtable_indices);
524 return vtable_indices;
525 }
526
527
528 InstanceKlass::InstanceKlass() {
529 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
530 }
531
532 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
533 Klass(kind),
534 _nest_members(nullptr),
535 _nest_host(nullptr),
536 _permitted_subclasses(nullptr),
537 _record_components(nullptr),
538 _static_field_size(parser.static_field_size()),
539 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
540 _itable_len(parser.itable_size()),
541 _nest_host_index(0),
542 _init_state(allocated),
543 _reference_type(reference_type),
544 _init_thread(nullptr)
545 {
546 set_vtable_length(parser.vtable_size());
547 set_access_flags(parser.access_flags());
548 if (parser.is_hidden()) set_is_hidden();
549 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
550 false));
551
552 assert(nullptr == _methods, "underlying memory not zeroed?");
553 assert(is_instance_klass(), "is layout incorrect?");
554 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
555 }
556
557 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
558 Array<Method*>* methods) {
559 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
560 !methods->in_aot_cache()) {
561 for (int i = 0; i < methods->length(); i++) {
562 Method* method = methods->at(i);
563 if (method == nullptr) continue; // maybe null if error processing
564 // Only want to delete methods that are not executing for RedefineClasses.
565 // The previous version will point to them so they're not totally dangling
566 assert (!method->on_stack(), "shouldn't be called with methods on stack");
567 MetadataFactory::free_metadata(loader_data, method);
568 }
569 MetadataFactory::free_array<Method*>(loader_data, methods);
570 }
571 }
572
573 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
574 const InstanceKlass* super_klass,
575 Array<InstanceKlass*>* local_interfaces,
576 Array<InstanceKlass*>* transitive_interfaces) {
577 // Only deallocate transitive interfaces if not empty, same as super class
578 // or same as local interfaces. See code in parseClassFile.
579 Array<InstanceKlass*>* ti = transitive_interfaces;
580 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
581 // check that the interfaces don't come from super class
582 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
583 super_klass->transitive_interfaces();
584 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
585 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
586 }
587 }
588
589 // local interfaces can be empty
590 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
591 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
592 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
593 }
594 }
595
596 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
597 Array<RecordComponent*>* record_components) {
598 if (record_components != nullptr && !record_components->in_aot_cache()) {
599 for (int i = 0; i < record_components->length(); i++) {
600 RecordComponent* record_component = record_components->at(i);
601 MetadataFactory::free_metadata(loader_data, record_component);
602 }
603 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
604 }
605 }
606
607 // This function deallocates the metadata and C heap pointers that the
608 // InstanceKlass points to.
609 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
610 // Orphan the mirror first, CMS thinks it's still live.
611 if (java_mirror() != nullptr) {
612 java_lang_Class::set_klass(java_mirror(), nullptr);
613 }
614
615 // Also remove mirror from handles
616 loader_data->remove_handle(_java_mirror);
617
618 // Need to take this class off the class loader data list.
619 loader_data->remove_class(this);
620
621 // The array_klass for this class is created later, after error handling.
622 // For class redefinition, we keep the original class so this scratch class
623 // doesn't have an array class. Either way, assert that there is nothing
624 // to deallocate.
625 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
626
627 // Release C heap allocated data that this points to, which includes
628 // reference counting symbol names.
629 // Can't release the constant pool or MethodData C heap data here because the constant
630 // pool can be deallocated separately from the InstanceKlass for default methods and
631 // redefine classes. MethodData can also be released separately.
632 release_C_heap_structures(/* release_sub_metadata */ false);
633
634 deallocate_methods(loader_data, methods());
635 set_methods(nullptr);
636
637 deallocate_record_components(loader_data, record_components());
638 set_record_components(nullptr);
639
640 if (method_ordering() != nullptr &&
641 method_ordering() != Universe::the_empty_int_array() &&
642 !method_ordering()->in_aot_cache()) {
643 MetadataFactory::free_array<int>(loader_data, method_ordering());
644 }
645 set_method_ordering(nullptr);
646
647 // default methods can be empty
648 if (default_methods() != nullptr &&
649 default_methods() != Universe::the_empty_method_array() &&
650 !default_methods()->in_aot_cache()) {
651 MetadataFactory::free_array<Method*>(loader_data, default_methods());
652 }
653 // Do NOT deallocate the default methods, they are owned by superinterfaces.
654 set_default_methods(nullptr);
655
656 // default methods vtable indices can be empty
657 if (default_vtable_indices() != nullptr &&
658 !default_vtable_indices()->in_aot_cache()) {
659 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
660 }
661 set_default_vtable_indices(nullptr);
662
663
664 // This array is in Klass, but remove it with the InstanceKlass since
665 // this place would be the only caller and it can share memory with transitive
666 // interfaces.
667 if (secondary_supers() != nullptr &&
668 secondary_supers() != Universe::the_empty_klass_array() &&
669 // see comments in compute_secondary_supers about the following cast
670 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
671 !secondary_supers()->in_aot_cache()) {
672 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
673 }
674 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
675
676 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
677 set_transitive_interfaces(nullptr);
678 set_local_interfaces(nullptr);
679
680 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
681 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
682 }
683 set_fieldinfo_stream(nullptr);
684
685 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
686 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
687 }
688 set_fieldinfo_search_table(nullptr);
689
690 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
691 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
692 }
693 set_fields_status(nullptr);
694
695 // If a method from a redefined class is using this constant pool, don't
696 // delete it, yet. The new class's previous version will point to this.
697 if (constants() != nullptr) {
698 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
699 if (!constants()->in_aot_cache()) {
700 MetadataFactory::free_metadata(loader_data, constants());
701 }
702 // Delete any cached resolution errors for the constant pool
703 SystemDictionary::delete_resolution_error(constants());
704
705 set_constants(nullptr);
706 }
707
708 if (inner_classes() != nullptr &&
709 inner_classes() != Universe::the_empty_short_array() &&
710 !inner_classes()->in_aot_cache()) {
711 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
712 }
713 set_inner_classes(nullptr);
714
715 if (nest_members() != nullptr &&
716 nest_members() != Universe::the_empty_short_array() &&
717 !nest_members()->in_aot_cache()) {
718 MetadataFactory::free_array<jushort>(loader_data, nest_members());
719 }
720 set_nest_members(nullptr);
721
722 if (permitted_subclasses() != nullptr &&
723 permitted_subclasses() != Universe::the_empty_short_array() &&
724 !permitted_subclasses()->in_aot_cache()) {
725 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
726 }
727 set_permitted_subclasses(nullptr);
728
729 // We should deallocate the Annotations instance if it's not in shared spaces.
730 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
731 MetadataFactory::free_metadata(loader_data, annotations());
732 }
733 set_annotations(nullptr);
734
735 SystemDictionaryShared::handle_class_unloading(this);
736
737 #if INCLUDE_CDS_JAVA_HEAP
738 if (CDSConfig::is_dumping_heap()) {
739 HeapShared::remove_scratch_objects(this);
740 }
741 #endif
742 }
743
744 bool InstanceKlass::is_record() const {
745 return _record_components != nullptr &&
746 is_final() &&
747 super() == vmClasses::Record_klass();
748 }
749
750 bool InstanceKlass::is_sealed() const {
751 return _permitted_subclasses != nullptr &&
752 _permitted_subclasses != Universe::the_empty_short_array();
753 }
754
755 // JLS 8.9: An enum class is either implicitly final and derives
756 // from java.lang.Enum, or else is implicitly sealed to its
757 // anonymous subclasses. This query detects both kinds.
758 // It does not validate the finality or
759 // sealing conditions: it merely checks for a super of Enum.
760 // This is sufficient for recognizing well-formed enums.
761 bool InstanceKlass::is_enum_subclass() const {
762 InstanceKlass* s = super();
763 return (s == vmClasses::Enum_klass() ||
764 (s != nullptr && s->super() == vmClasses::Enum_klass()));
765 }
766
767 bool InstanceKlass::should_be_initialized() const {
768 return !is_initialized();
769 }
770
771 klassItable InstanceKlass::itable() const {
772 return klassItable(const_cast<InstanceKlass*>(this));
773 }
774
775 // JVMTI spec thinks there are signers and protection domain in the
776 // instanceKlass. These accessors pretend these fields are there.
777 // The hprof specification also thinks these fields are in InstanceKlass.
778 oop InstanceKlass::protection_domain() const {
779 // return the protection_domain from the mirror
780 return java_lang_Class::protection_domain(java_mirror());
781 }
782
783 objArrayOop InstanceKlass::signers() const {
784 // return the signers from the mirror
785 return java_lang_Class::signers(java_mirror());
786 }
787
788 oop InstanceKlass::init_lock() const {
789 // return the init lock from the mirror
790 oop lock = java_lang_Class::init_lock(java_mirror());
791 // Prevent reordering with any access of initialization state
792 OrderAccess::loadload();
793 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
794 "only fully initialized state can have a null lock");
795 return lock;
796 }
797
798 // Set the initialization lock to null so the object can be GC'ed. Any racing
799 // threads to get this lock will see a null lock and will not lock.
800 // That's okay because they all check for initialized state after getting
801 // the lock and return. For preempted vthreads we keep the oop protected
802 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()).
803 void InstanceKlass::fence_and_clear_init_lock() {
804 // make sure previous stores are all done, notably the init_state.
805 OrderAccess::storestore();
806 java_lang_Class::clear_init_lock(java_mirror());
807 assert(!is_not_initialized(), "class must be initialized now");
808 }
809
810 class PreemptableInitCall {
811 JavaThread* _thread;
812 bool _previous;
813 DEBUG_ONLY(InstanceKlass* _previous_klass;)
814 public:
815 PreemptableInitCall(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
816 _previous = thread->at_preemptable_init();
817 _thread->set_at_preemptable_init(true);
818 DEBUG_ONLY(_previous_klass = _thread->preempt_init_klass();)
819 DEBUG_ONLY(_thread->set_preempt_init_klass(ik));
820 }
821 ~PreemptableInitCall() {
822 _thread->set_at_preemptable_init(_previous);
823 DEBUG_ONLY(_thread->set_preempt_init_klass(_previous_klass));
824 }
825 };
826
827 void InstanceKlass::initialize_preemptable(TRAPS) {
828 if (this->should_be_initialized()) {
829 PreemptableInitCall pic(THREAD, this);
830 initialize_impl(THREAD);
831 } else {
832 assert(is_initialized(), "sanity check");
833 }
834 }
835
836 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
837 // process. The step comments refers to the procedure described in that section.
838 // Note: implementation moved to static method to expose the this pointer.
839 void InstanceKlass::initialize(TRAPS) {
840 if (this->should_be_initialized()) {
841 initialize_impl(CHECK);
842 // Note: at this point the class may be initialized
843 // OR it may be in the state of being initialized
844 // in case of recursive initialization!
845 } else {
846 assert(is_initialized(), "sanity check");
847 }
848 }
849
850 #ifdef ASSERT
851 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
852 assert(has_aot_initialized_mirror(), "must be");
853
854 InstanceKlass* s = super();
855 if (s != nullptr) {
856 DEBUG_ONLY(ResourceMark rm);
857 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
858 s->external_name(), external_name());
859 s->assert_no_clinit_will_run_for_aot_initialized_class();
860 }
861
862 Array<InstanceKlass*>* interfaces = local_interfaces();
863 int len = interfaces->length();
864 for (int i = 0; i < len; i++) {
865 InstanceKlass* intf = interfaces->at(i);
866 if (!intf->is_initialized()) {
867 ResourceMark rm;
868 // Note: an interface needs to be marked as is_initialized() only if
869 // - it has a <clinit>
870 // - it has declared a default method.
871 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
872 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
873 intf->external_name(), external_name());
874 }
875 }
876 }
877 #endif
878
879 #if INCLUDE_CDS
880 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
881 assert(has_aot_initialized_mirror(), "must be");
882 assert(CDSConfig::is_loading_heap(), "must be");
883 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
884 assert_no_clinit_will_run_for_aot_initialized_class();
885
886 if (is_initialized()) {
887 return;
888 }
889
890 if (is_runtime_setup_required()) {
891 // Need to take the slow path, which will call the runtimeSetup() function instead
892 // of <clinit>
893 initialize(CHECK);
894 return;
895 }
896 if (log_is_enabled(Info, aot, init)) {
897 ResourceMark rm;
898 log_info(aot, init)("%s (aot-inited)", external_name());
899 }
900
901 link_class(CHECK);
902
903 #ifdef ASSERT
904 {
905 Handle h_init_lock(THREAD, init_lock());
906 ObjectLocker ol(h_init_lock, THREAD);
907 assert(!is_initialized(), "sanity");
908 assert(!is_being_initialized(), "sanity");
909 assert(!is_in_error_state(), "sanity");
910 }
911 #endif
912
913 set_init_thread(THREAD);
914 set_initialization_state_and_notify(fully_initialized, CHECK);
915 }
916 #endif
917
918 bool InstanceKlass::verify_code(TRAPS) {
919 // 1) Verify the bytecodes
920 return Verifier::verify(this, should_verify_class(), THREAD);
921 }
922
923 void InstanceKlass::link_class(TRAPS) {
924 assert(is_loaded(), "must be loaded");
925 if (!is_linked()) {
926 link_class_impl(CHECK);
927 }
928 }
929
930 // Called to verify that a class can link during initialization, without
931 // throwing a VerifyError.
932 bool InstanceKlass::link_class_or_fail(TRAPS) {
933 assert(is_loaded(), "must be loaded");
934 if (!is_linked()) {
935 link_class_impl(CHECK_false);
936 }
937 return is_linked();
938 }
939
940 bool InstanceKlass::link_class_impl(TRAPS) {
941 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
942 // This is for CDS static dump only -- we use the in_error_state to indicate that
943 // the class has failed verification. Throwing the NoClassDefFoundError here is just
944 // a convenient way to stop repeat attempts to verify the same (bad) class.
945 //
946 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
947 // if we are executing Java code. This is not a problem for CDS dumping phase since
948 // it doesn't execute any Java code.
949 ResourceMark rm(THREAD);
950 // Names are all known to be < 64k so we know this formatted message is not excessively large.
951 Exceptions::fthrow(THREAD_AND_LOCATION,
952 vmSymbols::java_lang_NoClassDefFoundError(),
953 "Class %s, or one of its supertypes, failed class initialization",
954 external_name());
955 return false;
956 }
957 // return if already verified
958 if (is_linked()) {
959 return true;
960 }
961
962 // Timing
963 // timer handles recursion
964 JavaThread* jt = THREAD;
965
966 // link super class before linking this class
967 InstanceKlass* super_klass = super();
968 if (super_klass != nullptr) {
969 if (super_klass->is_interface()) { // check if super class is an interface
970 ResourceMark rm(THREAD);
971 // Names are all known to be < 64k so we know this formatted message is not excessively large.
972 Exceptions::fthrow(
973 THREAD_AND_LOCATION,
974 vmSymbols::java_lang_IncompatibleClassChangeError(),
975 "class %s has interface %s as super class",
976 external_name(),
977 super_klass->external_name()
978 );
979 return false;
980 }
981
982 super_klass->link_class_impl(CHECK_false);
983 }
984
985 // link all interfaces implemented by this class before linking this class
986 Array<InstanceKlass*>* interfaces = local_interfaces();
987 int num_interfaces = interfaces->length();
988 for (int index = 0; index < num_interfaces; index++) {
989 InstanceKlass* interk = interfaces->at(index);
990 interk->link_class_impl(CHECK_false);
991 }
992
993 // in case the class is linked in the process of linking its superclasses
994 if (is_linked()) {
995 return true;
996 }
997
998 // trace only the link time for this klass that includes
999 // the verification time
1000 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1001 ClassLoader::perf_class_link_selftime(),
1002 ClassLoader::perf_classes_linked(),
1003 jt->get_thread_stat()->perf_recursion_counts_addr(),
1004 jt->get_thread_stat()->perf_timers_addr(),
1005 PerfClassTraceTime::CLASS_LINK);
1006
1007 // verification & rewriting
1008 {
1009 HandleMark hm(THREAD);
1010 Handle h_init_lock(THREAD, init_lock());
1011 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false);
1012 // Don't allow preemption if we link/initialize classes below,
1013 // since that would release this monitor while we are in the
1014 // middle of linking this class.
1015 NoPreemptMark npm(THREAD);
1016
1017 // rewritten will have been set if loader constraint error found
1018 // on an earlier link attempt
1019 // don't verify or rewrite if already rewritten
1020 //
1021
1022 if (!is_linked()) {
1023 if (!is_rewritten()) {
1024 if (in_aot_cache()) {
1025 assert(!verified_at_dump_time(), "must be");
1026 }
1027 {
1028 bool verify_ok = verify_code(THREAD);
1029 if (!verify_ok) {
1030 return false;
1031 }
1032 }
1033
1034 // Just in case a side-effect of verify linked this class already
1035 // (which can sometimes happen since the verifier loads classes
1036 // using custom class loaders, which are free to initialize things)
1037 if (is_linked()) {
1038 return true;
1039 }
1040
1041 // also sets rewritten
1042 rewrite_class(CHECK_false);
1043 } else if (in_aot_cache()) {
1044 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1045 }
1046
1047 // relocate jsrs and link methods after they are all rewritten
1048 link_methods(CHECK_false);
1049
1050 // Initialize the vtable and interface table after
1051 // methods have been rewritten since rewrite may
1052 // fabricate new Method*s.
1053 // also does loader constraint checking
1054 //
1055 // initialize_vtable and initialize_itable need to be rerun
1056 // for a shared class if
1057 // 1) the class is loaded by custom class loader or
1058 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1059 // 3) the class was not verified during dump time
1060 bool need_init_table = true;
1061 if (in_aot_cache() && verified_at_dump_time() &&
1062 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1063 need_init_table = false;
1064 }
1065 if (need_init_table) {
1066 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1067 itable().initialize_itable_and_check_constraints(CHECK_false);
1068 }
1069 #ifdef ASSERT
1070 vtable().verify(tty, true);
1071 // In case itable verification is ever added.
1072 // itable().verify(tty, true);
1073 #endif
1074 if (Universe::is_fully_initialized()) {
1075 DeoptimizationScope deopt_scope;
1076 {
1077 // Now mark all code that assumes the class is not linked.
1078 // Set state under the Compile_lock also.
1079 MutexLocker ml(THREAD, Compile_lock);
1080
1081 set_init_state(linked);
1082 CodeCache::mark_dependents_on(&deopt_scope, this);
1083 }
1084 // Perform the deopt handshake outside Compile_lock.
1085 deopt_scope.deoptimize_marked();
1086 } else {
1087 set_init_state(linked);
1088 }
1089 if (JvmtiExport::should_post_class_prepare()) {
1090 JvmtiExport::post_class_prepare(THREAD, this);
1091 }
1092 }
1093 }
1094 return true;
1095 }
1096
1097 // Rewrite the byte codes of all of the methods of a class.
1098 // The rewriter must be called exactly once. Rewriting must happen after
1099 // verification but before the first method of the class is executed.
1100 void InstanceKlass::rewrite_class(TRAPS) {
1101 assert(is_loaded(), "must be loaded");
1102 if (is_rewritten()) {
1103 assert(in_aot_cache(), "rewriting an unshared class?");
1104 return;
1105 }
1106 Rewriter::rewrite(this, CHECK);
1107 set_rewritten();
1108 }
1109
1110 // Now relocate and link method entry points after class is rewritten.
1111 // This is outside is_rewritten flag. In case of an exception, it can be
1112 // executed more than once.
1113 void InstanceKlass::link_methods(TRAPS) {
1114 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1115
1116 int len = methods()->length();
1117 for (int i = len-1; i >= 0; i--) {
1118 methodHandle m(THREAD, methods()->at(i));
1119 RuntimeUpcalls::install_upcalls(m);
1120
1121 // Set up method entry points for compiler and interpreter .
1122 m->link_method(m, CHECK);
1123 }
1124 }
1125
1126 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1127 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1128 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1129 for (int i = 0; i < local_interfaces()->length(); ++i) {
1130 InstanceKlass* ik = local_interfaces()->at(i);
1131
1132 // Initialization is depth first search ie. we start with top of the inheritance tree
1133 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1134 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1135 if (ik->has_nonstatic_concrete_methods()) {
1136 ik->initialize_super_interfaces(CHECK);
1137 }
1138
1139 // Only initialize() interfaces that "declare" concrete methods.
1140 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1141 ik->initialize(CHECK);
1142 }
1143 }
1144 }
1145
1146 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1147 static InitializationErrorTable* _initialization_error_table;
1148
1149 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1150 // Create the same exception with a message indicating the thread name,
1151 // and the StackTraceElements.
1152 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1153 ResourceMark rm(current);
1154 if (init_error.is_null()) {
1155 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1156
1157 // We failed to create the new exception, most likely due to either out-of-memory or
1158 // a stackoverflow error. If the original exception was either of those then we save
1159 // the shared, pre-allocated, stackless, instance of that exception.
1160 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1161 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1162 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1163 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1164 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1165 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1166 } else {
1167 return;
1168 }
1169 }
1170
1171 MutexLocker ml(current, ClassInitError_lock);
1172 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1173 bool created;
1174 if (_initialization_error_table == nullptr) {
1175 _initialization_error_table = new (mtClass) InitializationErrorTable();
1176 }
1177 _initialization_error_table->put_if_absent(this, elem, &created);
1178 assert(created, "Initialization is single threaded");
1179 log_trace(class, init)("Initialization error added for class %s", external_name());
1180 }
1181
1182 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1183 MutexLocker ml(current, ClassInitError_lock);
1184 if (_initialization_error_table == nullptr) {
1185 return nullptr;
1186 }
1187 OopHandle* h = _initialization_error_table->get(this);
1188 return (h != nullptr) ? h->resolve() : nullptr;
1189 }
1190
1191 // Need to remove entries for unloaded classes.
1192 void InstanceKlass::clean_initialization_error_table() {
1193 struct InitErrorTableCleaner {
1194 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1195 if (!ik->is_loader_alive()) {
1196 h.release(Universe::vm_global());
1197 return true;
1198 } else {
1199 return false;
1200 }
1201 }
1202 };
1203
1204 assert_locked_or_safepoint(ClassInitError_lock);
1205 InitErrorTableCleaner cleaner;
1206 if (_initialization_error_table != nullptr) {
1207 _initialization_error_table->unlink(&cleaner);
1208 }
1209 }
1210
1211 class ThreadWaitingForClassInit : public StackObj {
1212 JavaThread* _thread;
1213 public:
1214 ThreadWaitingForClassInit(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
1215 _thread->set_class_to_be_initialized(ik);
1216 }
1217 ~ThreadWaitingForClassInit() {
1218 _thread->set_class_to_be_initialized(nullptr);
1219 }
1220 };
1221
1222 void InstanceKlass::initialize_impl(TRAPS) {
1223 HandleMark hm(THREAD);
1224
1225 // Make sure klass is linked (verified) before initialization
1226 // A class could already be verified, since it has been reflected upon.
1227 link_class(CHECK);
1228
1229 DTRACE_CLASSINIT_PROBE(required, -1);
1230
1231 bool wait = false;
1232
1233 JavaThread* jt = THREAD;
1234
1235 if (ForceProfiling) {
1236 // Preallocate MDOs.
1237 for (int i = 0; i < methods()->length(); i++) {
1238 assert(!HAS_PENDING_EXCEPTION, "");
1239 methodHandle m(THREAD, methods()->at(i));
1240 Method::build_profiling_method_data(m, THREAD);
1241 if (HAS_PENDING_EXCEPTION) {
1242 ResourceMark rm;
1243 log_warning(cds)("MDO preallocation failed for %s", external_name());
1244 CLEAR_PENDING_EXCEPTION;
1245 break;
1246 }
1247 }
1248 }
1249
1250 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1251
1252 // refer to the JVM book page 47 for description of steps
1253 // Step 1
1254 {
1255 Handle h_init_lock(THREAD, init_lock());
1256 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE);
1257
1258 // Step 2
1259 // If we were to use wait() instead of waitInterruptibly() then
1260 // we might end up throwing IE from link/symbol resolution sites
1261 // that aren't expected to throw. This would wreak havoc. See 6320309.
1262 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1263 if (debug_logging_enabled) {
1264 ResourceMark rm(jt);
1265 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1266 jt->name(), external_name(), init_thread_name());
1267 }
1268 wait = true;
1269 ThreadWaitingForClassInit twcl(THREAD, this);
1270 ol.wait_uninterruptibly(CHECK_PREEMPTABLE);
1271 }
1272
1273 // Step 3
1274 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1275 if (debug_logging_enabled) {
1276 ResourceMark rm(jt);
1277 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1278 jt->name(), external_name());
1279 }
1280 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1281 return;
1282 }
1283
1284 // Step 4
1285 if (is_initialized()) {
1286 if (debug_logging_enabled) {
1287 ResourceMark rm(jt);
1288 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1289 jt->name(), external_name());
1290 }
1291 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1292 return;
1293 }
1294
1295 // Step 5
1296 if (is_in_error_state()) {
1297 if (debug_logging_enabled) {
1298 ResourceMark rm(jt);
1299 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1300 jt->name(), external_name());
1301 }
1302
1303 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1304 ResourceMark rm(THREAD);
1305 Handle cause(THREAD, get_initialization_error(THREAD));
1306
1307 stringStream ss;
1308 ss.print("Could not initialize class %s", external_name());
1309 if (cause.is_null()) {
1310 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1311 } else {
1312 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1313 ss.as_string(), cause);
1314 }
1315 } else {
1316
1317 // Step 6
1318 set_init_state(being_initialized);
1319 set_init_thread(jt);
1320 if (debug_logging_enabled) {
1321 ResourceMark rm(jt);
1322 log_debug(class, init)("Thread \"%s\" is initializing %s",
1323 jt->name(), external_name());
1324 }
1325 }
1326 }
1327
1328 // Block preemption once we are the initializer thread. Unmounting now
1329 // would complicate the reentrant case (identity is platform thread).
1330 NoPreemptMark npm(THREAD);
1331
1332 // Step 7
1333 // Next, if C is a class rather than an interface, initialize it's super class and super
1334 // interfaces.
1335 if (!is_interface()) {
1336 Klass* super_klass = super();
1337 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1338 super_klass->initialize(THREAD);
1339 }
1340 // If C implements any interface that declares a non-static, concrete method,
1341 // the initialization of C triggers initialization of its super interfaces.
1342 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1343 // having a superinterface that declares, non-static, concrete methods
1344 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1345 initialize_super_interfaces(THREAD);
1346 }
1347
1348 // If any exceptions, complete abruptly, throwing the same exception as above.
1349 if (HAS_PENDING_EXCEPTION) {
1350 Handle e(THREAD, PENDING_EXCEPTION);
1351 CLEAR_PENDING_EXCEPTION;
1352 {
1353 EXCEPTION_MARK;
1354 add_initialization_error(THREAD, e);
1355 // Locks object, set state, and notify all waiting threads
1356 set_initialization_state_and_notify(initialization_error, THREAD);
1357 CLEAR_PENDING_EXCEPTION;
1358 }
1359 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1360 THROW_OOP(e());
1361 }
1362 }
1363
1364
1365 // Step 8
1366 {
1367 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1368 if (class_initializer() != nullptr) {
1369 // Timer includes any side effects of class initialization (resolution,
1370 // etc), but not recursive entry into call_class_initializer().
1371 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1372 ClassLoader::perf_class_init_selftime(),
1373 ClassLoader::perf_classes_inited(),
1374 jt->get_thread_stat()->perf_recursion_counts_addr(),
1375 jt->get_thread_stat()->perf_timers_addr(),
1376 PerfClassTraceTime::CLASS_CLINIT);
1377 call_class_initializer(THREAD);
1378 } else {
1379 // The elapsed time is so small it's not worth counting.
1380 if (UsePerfData) {
1381 ClassLoader::perf_classes_inited()->inc();
1382 }
1383 call_class_initializer(THREAD);
1384 }
1385 }
1386
1387 // Step 9
1388 if (!HAS_PENDING_EXCEPTION) {
1389 set_initialization_state_and_notify(fully_initialized, CHECK);
1390 DEBUG_ONLY(vtable().verify(tty, true);)
1391 CompilationPolicy::replay_training_at_init(this, THREAD);
1392 }
1393 else {
1394 // Step 10 and 11
1395 Handle e(THREAD, PENDING_EXCEPTION);
1396 CLEAR_PENDING_EXCEPTION;
1397 // JVMTI has already reported the pending exception
1398 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1399 JvmtiExport::clear_detected_exception(jt);
1400 {
1401 EXCEPTION_MARK;
1402 add_initialization_error(THREAD, e);
1403 set_initialization_state_and_notify(initialization_error, THREAD);
1404 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1405 // JVMTI has already reported the pending exception
1406 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1407 JvmtiExport::clear_detected_exception(jt);
1408 }
1409 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1410 if (e->is_a(vmClasses::Error_klass())) {
1411 THROW_OOP(e());
1412 } else {
1413 JavaCallArguments args(e);
1414 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1415 vmSymbols::throwable_void_signature(),
1416 &args);
1417 }
1418 }
1419 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1420 }
1421
1422 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1423 Handle h_init_lock(THREAD, init_lock());
1424 if (h_init_lock() != nullptr) {
1425 ObjectLocker ol(h_init_lock, THREAD);
1426 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1427 set_init_state(state);
1428 fence_and_clear_init_lock();
1429 ol.notify_all(CHECK);
1430 } else {
1431 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1432 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1433 set_init_state(state);
1434 }
1435 }
1436
1437 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1438 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1439 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1440 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1441
1442 DeoptimizationScope deopt_scope;
1443 {
1444 MutexLocker ml(current, Compile_lock);
1445
1446 set_init_state(InstanceKlass::loaded);
1447 // make sure init_state store is already done.
1448 // The compiler reads the hierarchy outside of the Compile_lock.
1449 // Access ordering is used to add to hierarchy.
1450
1451 // Link into hierarchy.
1452 append_to_sibling_list(); // add to superklass/sibling list
1453 process_interfaces(); // handle all "implements" declarations
1454
1455 // Now mark all code that depended on old class hierarchy.
1456 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1457 if (Universe::is_fully_initialized()) {
1458 CodeCache::mark_dependents_on(&deopt_scope, this);
1459 }
1460 }
1461 // Perform the deopt handshake outside Compile_lock.
1462 deopt_scope.deoptimize_marked();
1463 }
1464
1465
1466 InstanceKlass* InstanceKlass::implementor() const {
1467 InstanceKlass* volatile* ik = adr_implementor();
1468 if (ik == nullptr) {
1469 return nullptr;
1470 } else {
1471 // This load races with inserts, and therefore needs acquire.
1472 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1473 if (ikls != nullptr && !ikls->is_loader_alive()) {
1474 return nullptr; // don't return unloaded class
1475 } else {
1476 return ikls;
1477 }
1478 }
1479 }
1480
1481
1482 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1483 assert_locked_or_safepoint(Compile_lock);
1484 assert(is_interface(), "not interface");
1485 InstanceKlass* volatile* addr = adr_implementor();
1486 assert(addr != nullptr, "null addr");
1487 if (addr != nullptr) {
1488 AtomicAccess::release_store(addr, ik);
1489 }
1490 }
1491
1492 int InstanceKlass::nof_implementors() const {
1493 InstanceKlass* ik = implementor();
1494 if (ik == nullptr) {
1495 return 0;
1496 } else if (ik != this) {
1497 return 1;
1498 } else {
1499 return 2;
1500 }
1501 }
1502
1503 // The embedded _implementor field can only record one implementor.
1504 // When there are more than one implementors, the _implementor field
1505 // is set to the interface Klass* itself. Following are the possible
1506 // values for the _implementor field:
1507 // null - no implementor
1508 // implementor Klass* - one implementor
1509 // self - more than one implementor
1510 //
1511 // The _implementor field only exists for interfaces.
1512 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1513 if (Universe::is_fully_initialized()) {
1514 assert_lock_strong(Compile_lock);
1515 }
1516 assert(is_interface(), "not interface");
1517 // Filter out my subinterfaces.
1518 // (Note: Interfaces are never on the subklass list.)
1519 if (ik->is_interface()) return;
1520
1521 // Filter out subclasses whose supers already implement me.
1522 // (Note: CHA must walk subclasses of direct implementors
1523 // in order to locate indirect implementors.)
1524 InstanceKlass* super_ik = ik->super();
1525 if (super_ik != nullptr && super_ik->implements_interface(this))
1526 // We only need to check one immediate superclass, since the
1527 // implements_interface query looks at transitive_interfaces.
1528 // Any supers of the super have the same (or fewer) transitive_interfaces.
1529 return;
1530
1531 InstanceKlass* iklass = implementor();
1532 if (iklass == nullptr) {
1533 set_implementor(ik);
1534 } else if (iklass != this && iklass != ik) {
1535 // There is already an implementor. Use itself as an indicator of
1536 // more than one implementors.
1537 set_implementor(this);
1538 }
1539
1540 // The implementor also implements the transitive_interfaces
1541 for (int index = 0; index < local_interfaces()->length(); index++) {
1542 local_interfaces()->at(index)->add_implementor(ik);
1543 }
1544 }
1545
1546 void InstanceKlass::init_implementor() {
1547 if (is_interface()) {
1548 set_implementor(nullptr);
1549 }
1550 }
1551
1552
1553 void InstanceKlass::process_interfaces() {
1554 // link this class into the implementors list of every interface it implements
1555 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1556 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1557 InstanceKlass* interf = local_interfaces()->at(i);
1558 assert(interf->is_interface(), "expected interface");
1559 interf->add_implementor(this);
1560 }
1561 }
1562
1563 bool InstanceKlass::can_be_primary_super_slow() const {
1564 if (is_interface())
1565 return false;
1566 else
1567 return Klass::can_be_primary_super_slow();
1568 }
1569
1570 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1571 Array<InstanceKlass*>* transitive_interfaces) {
1572 // The secondaries are the implemented interfaces.
1573 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1574 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1575 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1576 int num_secondaries = num_extra_slots + interfaces->length();
1577 if (num_secondaries == 0) {
1578 // Must share this for correct bootstrapping!
1579 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1580 return nullptr;
1581 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1582 // We will reuse the transitive interfaces list if we're certain
1583 // it's in hash order.
1584 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1585 set_secondary_supers(interfaces, bitmap);
1586 return nullptr;
1587 }
1588 // Copy transitive interfaces to a temporary growable array to be constructed
1589 // into the secondary super list with extra slots.
1590 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1591 for (int i = 0; i < interfaces->length(); i++) {
1592 secondaries->push(interfaces->at(i));
1593 }
1594 return secondaries;
1595 }
1596
1597 bool InstanceKlass::implements_interface(Klass* k) const {
1598 if (this == k) return true;
1599 assert(k->is_interface(), "should be an interface class");
1600 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1601 if (transitive_interfaces()->at(i) == k) {
1602 return true;
1603 }
1604 }
1605 return false;
1606 }
1607
1608 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1609 // Verify direct super interface
1610 if (this == k) return true;
1611 assert(k->is_interface(), "should be an interface class");
1612 for (int i = 0; i < local_interfaces()->length(); i++) {
1613 if (local_interfaces()->at(i) == k) {
1614 return true;
1615 }
1616 }
1617 return false;
1618 }
1619
1620 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1621 if (TraceFinalizerRegistration) {
1622 tty->print("Registered ");
1623 i->print_value_on(tty);
1624 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1625 }
1626 instanceHandle h_i(THREAD, i);
1627 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1628 JavaValue result(T_VOID);
1629 JavaCallArguments args(h_i);
1630 methodHandle mh(THREAD, Universe::finalizer_register_method());
1631 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1632 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1633 return h_i();
1634 }
1635
1636 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1637 assert(!is_abstract() && !is_interface(), "Should not create this object");
1638 size_t size = size_helper(); // Query before forming handle.
1639 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1640 }
1641
1642 instanceOop InstanceKlass::allocate_instance(oop java_class,
1643 const char* who,
1644 TRAPS) {
1645 Klass* k = java_lang_Class::as_Klass(java_class);
1646 if (k == nullptr) {
1647 ResourceMark rm(THREAD);
1648 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1649 }
1650 InstanceKlass* ik = cast(k);
1651 ik->check_valid_for_instantiation(false, CHECK_NULL);
1652 ik->initialize(CHECK_NULL);
1653 return ik->allocate_instance(THREAD);
1654 }
1655
1656 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1657 return instanceHandle(THREAD, allocate_instance(THREAD));
1658 }
1659
1660 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1661 if (is_interface() || is_abstract()) {
1662 ResourceMark rm(THREAD);
1663 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1664 : vmSymbols::java_lang_InstantiationException(), external_name());
1665 }
1666 if (this == vmClasses::Class_klass()) {
1667 ResourceMark rm(THREAD);
1668 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1669 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1670 }
1671 }
1672
1673 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1674 // Need load-acquire for lock-free read
1675 if (array_klasses_acquire() == nullptr) {
1676
1677 // Recursively lock array allocation
1678 RecursiveLocker rl(MultiArray_lock, THREAD);
1679
1680 // Check if another thread created the array klass while we were waiting for the lock.
1681 if (array_klasses() == nullptr) {
1682 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1683 // use 'release' to pair with lock-free load
1684 release_set_array_klasses(k);
1685 }
1686 }
1687
1688 // array_klasses() will always be set at this point
1689 ObjArrayKlass* ak = array_klasses();
1690 assert(ak != nullptr, "should be set");
1691 return ak->array_klass(n, THREAD);
1692 }
1693
1694 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1695 // Need load-acquire for lock-free read
1696 ObjArrayKlass* oak = array_klasses_acquire();
1697 if (oak == nullptr) {
1698 return nullptr;
1699 } else {
1700 return oak->array_klass_or_null(n);
1701 }
1702 }
1703
1704 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1705 return array_klass(1, THREAD);
1706 }
1707
1708 ArrayKlass* InstanceKlass::array_klass_or_null() {
1709 return array_klass_or_null(1);
1710 }
1711
1712 static int call_class_initializer_counter = 0; // for debugging
1713
1714 Method* InstanceKlass::class_initializer() const {
1715 Method* clinit = find_method(
1716 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1717 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1718 return clinit;
1719 }
1720 return nullptr;
1721 }
1722
1723 void InstanceKlass::call_class_initializer(TRAPS) {
1724 if (ReplayCompiles &&
1725 (ReplaySuppressInitializers == 1 ||
1726 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1727 // Hide the existence of the initializer for the purpose of replaying the compile
1728 return;
1729 }
1730
1731 #if INCLUDE_CDS
1732 // This is needed to ensure the consistency of the archived heap objects.
1733 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1734 AOTClassInitializer::call_runtime_setup(THREAD, this);
1735 return;
1736 } else if (has_archived_enum_objs()) {
1737 assert(in_aot_cache(), "must be");
1738 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1739 if (initialized) {
1740 return;
1741 }
1742 }
1743 #endif
1744
1745 methodHandle h_method(THREAD, class_initializer());
1746 assert(!is_initialized(), "we cannot initialize twice");
1747
1748 #if 0
1749 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1750 int init_id = log_class_init(THREAD, this);
1751 if (h_method() != nullptr) {
1752 JavaCallArguments args; // No arguments
1753 JavaValue result(T_VOID);
1754 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1755 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1756
1757 elapsedTimer timer;
1758 {
1759 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1760 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1761
1762 timer.start();
1763 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1764 timer.stop();
1765 }
1766
1767 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1768
1769 jlong bc_executed = (bc_end - bc_start);
1770 if (UsePerfData && outer == nullptr) { // outermost clinit
1771 THREAD->inc_clinit_bc_counter_value(bc_executed);
1772 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1773 }
1774
1775 THREAD->set_class_being_initialized(outer);
1776
1777 LogStreamHandle(Debug, init) log;
1778 if (log.is_enabled()) {
1779 ResourceMark rm(THREAD);
1780 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1781 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1782 if (CountBytecodes || CountBytecodesPerThread) {
1783 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1784 }
1785 name()->print_value_on(&log);
1786 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1787 p2i(THREAD), THREAD->name(), p2i(this));
1788 }
1789 }
1790 LogTarget(Info, class, init) lt;
1791 if (lt.is_enabled()) {
1792 ResourceMark rm(THREAD);
1793 LogStream ls(lt);
1794 ls.print("%d Initialized ", init_id);
1795 name()->print_value_on(&ls);
1796 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1797 h_method() == nullptr ? "(no method)" : "", p2i(this),
1798 THREAD->name());
1799 }
1800 #else
1801 LogTarget(Info, class, init) lt;
1802 if (lt.is_enabled()) {
1803 ResourceMark rm(THREAD);
1804 LogStream ls(lt);
1805 ls.print("%d Initializing ", call_class_initializer_counter++);
1806 name()->print_value_on(&ls);
1807 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1808 h_method() == nullptr ? "(no method)" : "", p2i(this),
1809 THREAD->name());
1810 }
1811 if (h_method() != nullptr) {
1812 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1813 JavaCallArguments args; // No arguments
1814 JavaValue result(T_VOID);
1815 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1816 }
1817 #endif
1818 }
1819
1820 // If a class that implements this interface is initialized, is the JVM required
1821 // to first execute a <clinit> method declared in this interface,
1822 // or (if also_check_supers==true) any of the super types of this interface?
1823 //
1824 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1825 // an interface, then let SC be its superclass and let SI1, ..., SIn
1826 // be all superinterfaces of C (whether direct or indirect) that
1827 // declare at least one non-abstract, non-static method.
1828 //
1829 // So when an interface is initialized, it does not look at its
1830 // supers. But a proper class will ensure that all of its supers have
1831 // run their <clinit> methods, except that it disregards interfaces
1832 // that lack a non-static concrete method (i.e., a default method).
1833 // Therefore, you should probably call this method only when the
1834 // current class is a super of some proper class, not an interface.
1835 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1836 assert(is_interface(), "must be");
1837
1838 if (!has_nonstatic_concrete_methods()) {
1839 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1840 return false;
1841 }
1842
1843 // JVMS 5.5. Initialization
1844 // ...If C is an interface that declares a non-abstract,
1845 // non-static method, the initialization of a class that
1846 // implements C directly or indirectly.
1847 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1848 return true;
1849 }
1850 if (also_check_supers) {
1851 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1852 for (int i = 0; i < all_ifs->length(); ++i) {
1853 InstanceKlass* super_intf = all_ifs->at(i);
1854 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1855 return true;
1856 }
1857 }
1858 }
1859 return false;
1860 }
1861
1862 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1863 InterpreterOopMap* entry_for) {
1864 // Lazily create the _oop_map_cache at first request.
1865 // Load_acquire is needed to safely get instance published with CAS by another thread.
1866 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
1867 if (oop_map_cache == nullptr) {
1868 // Try to install new instance atomically.
1869 oop_map_cache = new OopMapCache();
1870 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1871 if (other != nullptr) {
1872 // Someone else managed to install before us, ditch local copy and use the existing one.
1873 delete oop_map_cache;
1874 oop_map_cache = other;
1875 }
1876 }
1877 // _oop_map_cache is constant after init; lookup below does its own locking.
1878 oop_map_cache->lookup(method, bci, entry_for);
1879 }
1880
1881 bool InstanceKlass::contains_field_offset(int offset) {
1882 fieldDescriptor fd;
1883 return find_field_from_offset(offset, false, &fd);
1884 }
1885
1886 FieldInfo InstanceKlass::field(int index) const {
1887 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1888 if (fs.index() == index) {
1889 return fs.to_FieldInfo();
1890 }
1891 }
1892 fatal("Field not found");
1893 return FieldInfo();
1894 }
1895
1896 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1897 JavaFieldStream fs(this);
1898 if (fs.lookup(name, sig)) {
1899 assert(fs.name() == name, "name must match");
1900 assert(fs.signature() == sig, "signature must match");
1901 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1902 return true;
1903 }
1904 return false;
1905 }
1906
1907
1908 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1909 const int n = local_interfaces()->length();
1910 for (int i = 0; i < n; i++) {
1911 InstanceKlass* intf1 = local_interfaces()->at(i);
1912 assert(intf1->is_interface(), "just checking type");
1913 // search for field in current interface
1914 if (intf1->find_local_field(name, sig, fd)) {
1915 assert(fd->is_static(), "interface field must be static");
1916 return intf1;
1917 }
1918 // search for field in direct superinterfaces
1919 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
1920 if (intf2 != nullptr) return intf2;
1921 }
1922 // otherwise field lookup fails
1923 return nullptr;
1924 }
1925
1926
1927 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1928 // search order according to newest JVM spec (5.4.3.2, p.167).
1929 // 1) search for field in current klass
1930 if (find_local_field(name, sig, fd)) {
1931 return const_cast<InstanceKlass*>(this);
1932 }
1933 // 2) search for field recursively in direct superinterfaces
1934 { Klass* intf = find_interface_field(name, sig, fd);
1935 if (intf != nullptr) return intf;
1936 }
1937 // 3) apply field lookup recursively if superclass exists
1938 { InstanceKlass* supr = super();
1939 if (supr != nullptr) return supr->find_field(name, sig, fd);
1940 }
1941 // 4) otherwise field lookup fails
1942 return nullptr;
1943 }
1944
1945
1946 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1947 // search order according to newest JVM spec (5.4.3.2, p.167).
1948 // 1) search for field in current klass
1949 if (find_local_field(name, sig, fd)) {
1950 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1951 }
1952 // 2) search for field recursively in direct superinterfaces
1953 if (is_static) {
1954 Klass* intf = find_interface_field(name, sig, fd);
1955 if (intf != nullptr) return intf;
1956 }
1957 // 3) apply field lookup recursively if superclass exists
1958 { InstanceKlass* supr = super();
1959 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
1960 }
1961 // 4) otherwise field lookup fails
1962 return nullptr;
1963 }
1964
1965
1966 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1967 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1968 if (fs.offset() == offset) {
1969 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1970 if (fd->is_static() == is_static) return true;
1971 }
1972 }
1973 return false;
1974 }
1975
1976
1977 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1978 const InstanceKlass* klass = this;
1979 while (klass != nullptr) {
1980 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
1981 return true;
1982 }
1983 klass = klass->super();
1984 }
1985 return false;
1986 }
1987
1988
1989 void InstanceKlass::methods_do(void f(Method* method)) {
1990 // Methods aren't stable until they are loaded. This can be read outside
1991 // a lock through the ClassLoaderData for profiling
1992 // Redefined scratch classes are on the list and need to be cleaned
1993 if (!is_loaded() && !is_scratch_class()) {
1994 return;
1995 }
1996
1997 int len = methods()->length();
1998 for (int index = 0; index < len; index++) {
1999 Method* m = methods()->at(index);
2000 assert(m->is_method(), "must be method");
2001 f(m);
2002 }
2003 }
2004
2005
2006 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2007 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2008 if (fs.access_flags().is_static()) {
2009 fieldDescriptor& fd = fs.field_descriptor();
2010 cl->do_field(&fd);
2011 }
2012 }
2013 }
2014
2015
2016 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2017 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2018 if (fs.access_flags().is_static()) {
2019 fieldDescriptor& fd = fs.field_descriptor();
2020 f(&fd, mirror, CHECK);
2021 }
2022 }
2023 }
2024
2025 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2026 InstanceKlass* super = this->super();
2027 if (super != nullptr) {
2028 super->do_nonstatic_fields(cl);
2029 }
2030 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2031 fieldDescriptor& fd = fs.field_descriptor();
2032 if (!fd.is_static()) {
2033 cl->do_field(&fd);
2034 }
2035 }
2036 }
2037
2038 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2039 return a->offset() - b->offset();
2040 }
2041
2042 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2043 InstanceKlass* super = this->super();
2044 if (super != nullptr) {
2045 super->print_nonstatic_fields(cl);
2046 }
2047 ResourceMark rm;
2048 // In DebugInfo nonstatic fields are sorted by offset.
2049 GrowableArray<FieldInfo> fields_sorted;
2050 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2051 if (!fs.access_flags().is_static()) {
2052 fields_sorted.push(fs.to_FieldInfo());
2053 }
2054 }
2055 int length = fields_sorted.length();
2056 if (length > 0) {
2057 fields_sorted.sort(compare_fields_by_offset);
2058 fieldDescriptor fd;
2059 for (int i = 0; i < length; i++) {
2060 fd.reinitialize(this, fields_sorted.at(i));
2061 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2062 cl->do_field(&fd);
2063 }
2064 }
2065 }
2066
2067 #ifdef ASSERT
2068 static int linear_search(const Array<Method*>* methods,
2069 const Symbol* name,
2070 const Symbol* signature) {
2071 const int len = methods->length();
2072 for (int index = 0; index < len; index++) {
2073 const Method* const m = methods->at(index);
2074 assert(m->is_method(), "must be method");
2075 if (m->signature() == signature && m->name() == name) {
2076 return index;
2077 }
2078 }
2079 return -1;
2080 }
2081 #endif
2082
2083 bool InstanceKlass::_disable_method_binary_search = false;
2084
2085 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2086 int len = methods->length();
2087 int l = 0;
2088 int h = len - 1;
2089 while (l <= h) {
2090 Method* m = methods->at(l);
2091 if (m->name() == name) {
2092 return l;
2093 }
2094 l++;
2095 }
2096 return -1;
2097 }
2098
2099 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2100 if (_disable_method_binary_search) {
2101 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2102 // At the final stage of dynamic dumping, the methods array may not be sorted
2103 // by ascending addresses of their names, so we can't use binary search anymore.
2104 // However, methods with the same name are still laid out consecutively inside the
2105 // methods array, so let's look for the first one that matches.
2106 return linear_search(methods, name);
2107 }
2108
2109 int len = methods->length();
2110 int l = 0;
2111 int h = len - 1;
2112
2113 // methods are sorted by ascending addresses of their names, so do binary search
2114 while (l <= h) {
2115 int mid = (l + h) >> 1;
2116 Method* m = methods->at(mid);
2117 assert(m->is_method(), "must be method");
2118 int res = m->name()->fast_compare(name);
2119 if (res == 0) {
2120 return mid;
2121 } else if (res < 0) {
2122 l = mid + 1;
2123 } else {
2124 h = mid - 1;
2125 }
2126 }
2127 return -1;
2128 }
2129
2130 // find_method looks up the name/signature in the local methods array
2131 Method* InstanceKlass::find_method(const Symbol* name,
2132 const Symbol* signature) const {
2133 return find_method_impl(name, signature,
2134 OverpassLookupMode::find,
2135 StaticLookupMode::find,
2136 PrivateLookupMode::find);
2137 }
2138
2139 Method* InstanceKlass::find_method_impl(const Symbol* name,
2140 const Symbol* signature,
2141 OverpassLookupMode overpass_mode,
2142 StaticLookupMode static_mode,
2143 PrivateLookupMode private_mode) const {
2144 return InstanceKlass::find_method_impl(methods(),
2145 name,
2146 signature,
2147 overpass_mode,
2148 static_mode,
2149 private_mode);
2150 }
2151
2152 // find_instance_method looks up the name/signature in the local methods array
2153 // and skips over static methods
2154 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2155 const Symbol* name,
2156 const Symbol* signature,
2157 PrivateLookupMode private_mode) {
2158 Method* const meth = InstanceKlass::find_method_impl(methods,
2159 name,
2160 signature,
2161 OverpassLookupMode::find,
2162 StaticLookupMode::skip,
2163 private_mode);
2164 assert(((meth == nullptr) || !meth->is_static()),
2165 "find_instance_method should have skipped statics");
2166 return meth;
2167 }
2168
2169 // find_instance_method looks up the name/signature in the local methods array
2170 // and skips over static methods
2171 Method* InstanceKlass::find_instance_method(const Symbol* name,
2172 const Symbol* signature,
2173 PrivateLookupMode private_mode) const {
2174 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2175 }
2176
2177 // Find looks up the name/signature in the local methods array
2178 // and filters on the overpass, static and private flags
2179 // This returns the first one found
2180 // note that the local methods array can have up to one overpass, one static
2181 // and one instance (private or not) with the same name/signature
2182 Method* InstanceKlass::find_local_method(const Symbol* name,
2183 const Symbol* signature,
2184 OverpassLookupMode overpass_mode,
2185 StaticLookupMode static_mode,
2186 PrivateLookupMode private_mode) const {
2187 return InstanceKlass::find_method_impl(methods(),
2188 name,
2189 signature,
2190 overpass_mode,
2191 static_mode,
2192 private_mode);
2193 }
2194
2195 // Find looks up the name/signature in the local methods array
2196 // and filters on the overpass, static and private flags
2197 // This returns the first one found
2198 // note that the local methods array can have up to one overpass, one static
2199 // and one instance (private or not) with the same name/signature
2200 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2201 const Symbol* name,
2202 const Symbol* signature,
2203 OverpassLookupMode overpass_mode,
2204 StaticLookupMode static_mode,
2205 PrivateLookupMode private_mode) {
2206 return InstanceKlass::find_method_impl(methods,
2207 name,
2208 signature,
2209 overpass_mode,
2210 static_mode,
2211 private_mode);
2212 }
2213
2214 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2215 const Symbol* name,
2216 const Symbol* signature) {
2217 return InstanceKlass::find_method_impl(methods,
2218 name,
2219 signature,
2220 OverpassLookupMode::find,
2221 StaticLookupMode::find,
2222 PrivateLookupMode::find);
2223 }
2224
2225 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2226 const Symbol* name,
2227 const Symbol* signature,
2228 OverpassLookupMode overpass_mode,
2229 StaticLookupMode static_mode,
2230 PrivateLookupMode private_mode) {
2231 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2232 return hit >= 0 ? methods->at(hit): nullptr;
2233 }
2234
2235 // true if method matches signature and conforms to skipping_X conditions.
2236 static bool method_matches(const Method* m,
2237 const Symbol* signature,
2238 bool skipping_overpass,
2239 bool skipping_static,
2240 bool skipping_private) {
2241 return ((m->signature() == signature) &&
2242 (!skipping_overpass || !m->is_overpass()) &&
2243 (!skipping_static || !m->is_static()) &&
2244 (!skipping_private || !m->is_private()));
2245 }
2246
2247 // Used directly for default_methods to find the index into the
2248 // default_vtable_indices, and indirectly by find_method
2249 // find_method_index looks in the local methods array to return the index
2250 // of the matching name/signature. If, overpass methods are being ignored,
2251 // the search continues to find a potential non-overpass match. This capability
2252 // is important during method resolution to prefer a static method, for example,
2253 // over an overpass method.
2254 // There is the possibility in any _method's array to have the same name/signature
2255 // for a static method, an overpass method and a local instance method
2256 // To correctly catch a given method, the search criteria may need
2257 // to explicitly skip the other two. For local instance methods, it
2258 // is often necessary to skip private methods
2259 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2260 const Symbol* name,
2261 const Symbol* signature,
2262 OverpassLookupMode overpass_mode,
2263 StaticLookupMode static_mode,
2264 PrivateLookupMode private_mode) {
2265 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2266 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2267 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2268 const int hit = quick_search(methods, name);
2269 if (hit != -1) {
2270 const Method* const m = methods->at(hit);
2271
2272 // Do linear search to find matching signature. First, quick check
2273 // for common case, ignoring overpasses if requested.
2274 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2275 return hit;
2276 }
2277
2278 // search downwards through overloaded methods
2279 int i;
2280 for (i = hit - 1; i >= 0; --i) {
2281 const Method* const m = methods->at(i);
2282 assert(m->is_method(), "must be method");
2283 if (m->name() != name) {
2284 break;
2285 }
2286 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2287 return i;
2288 }
2289 }
2290 // search upwards
2291 for (i = hit + 1; i < methods->length(); ++i) {
2292 const Method* const m = methods->at(i);
2293 assert(m->is_method(), "must be method");
2294 if (m->name() != name) {
2295 break;
2296 }
2297 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2298 return i;
2299 }
2300 }
2301 // not found
2302 #ifdef ASSERT
2303 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2304 linear_search(methods, name, signature);
2305 assert(-1 == index, "binary search should have found entry %d", index);
2306 #endif
2307 }
2308 return -1;
2309 }
2310
2311 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2312 return find_method_by_name(methods(), name, end);
2313 }
2314
2315 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2316 const Symbol* name,
2317 int* end_ptr) {
2318 assert(end_ptr != nullptr, "just checking");
2319 int start = quick_search(methods, name);
2320 int end = start + 1;
2321 if (start != -1) {
2322 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2323 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2324 *end_ptr = end;
2325 return start;
2326 }
2327 return -1;
2328 }
2329
2330 // uncached_lookup_method searches both the local class methods array and all
2331 // superclasses methods arrays, skipping any overpass methods in superclasses,
2332 // and possibly skipping private methods.
2333 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2334 const Symbol* signature,
2335 OverpassLookupMode overpass_mode,
2336 PrivateLookupMode private_mode) const {
2337 OverpassLookupMode overpass_local_mode = overpass_mode;
2338 const InstanceKlass* klass = this;
2339 while (klass != nullptr) {
2340 Method* const method = klass->find_method_impl(name,
2341 signature,
2342 overpass_local_mode,
2343 StaticLookupMode::find,
2344 private_mode);
2345 if (method != nullptr) {
2346 return method;
2347 }
2348 klass = klass->super();
2349 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2350 }
2351 return nullptr;
2352 }
2353
2354 #ifdef ASSERT
2355 // search through class hierarchy and return true if this class or
2356 // one of the superclasses was redefined
2357 bool InstanceKlass::has_redefined_this_or_super() const {
2358 const InstanceKlass* klass = this;
2359 while (klass != nullptr) {
2360 if (klass->has_been_redefined()) {
2361 return true;
2362 }
2363 klass = klass->super();
2364 }
2365 return false;
2366 }
2367 #endif
2368
2369 // lookup a method in the default methods list then in all transitive interfaces
2370 // Do NOT return private or static methods
2371 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2372 Symbol* signature) const {
2373 Method* m = nullptr;
2374 if (default_methods() != nullptr) {
2375 m = find_method(default_methods(), name, signature);
2376 }
2377 // Look up interfaces
2378 if (m == nullptr) {
2379 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2380 }
2381 return m;
2382 }
2383
2384 // lookup a method in all the interfaces that this class implements
2385 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2386 // They should only be found in the initial InterfaceMethodRef
2387 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2388 Symbol* signature,
2389 DefaultsLookupMode defaults_mode) const {
2390 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2391 int num_ifs = all_ifs->length();
2392 InstanceKlass *ik = nullptr;
2393 for (int i = 0; i < num_ifs; i++) {
2394 ik = all_ifs->at(i);
2395 Method* m = ik->lookup_method(name, signature);
2396 if (m != nullptr && m->is_public() && !m->is_static() &&
2397 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2398 return m;
2399 }
2400 }
2401 return nullptr;
2402 }
2403
2404 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2405 :_st(st), _verbose(verbose) {
2406 ResourceMark rm;
2407 _st->print("%-18s ", "KlassAddr");
2408 _st->print("%-4s ", "Size");
2409 _st->print("%-20s ", "State");
2410 _st->print("%-7s ", "Flags");
2411 _st->print("%-5s ", "ClassName");
2412 _st->cr();
2413 }
2414
2415 void PrintClassClosure::do_klass(Klass* k) {
2416 ResourceMark rm;
2417 // klass pointer
2418 _st->print(PTR_FORMAT " ", p2i(k));
2419 // klass size
2420 _st->print("%4d ", k->size());
2421 // initialization state
2422 if (k->is_instance_klass()) {
2423 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2424 } else {
2425 _st->print("%-20s ","");
2426 }
2427 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2428 char buf[10];
2429 int i = 0;
2430 if (k->has_finalizer()) buf[i++] = 'F';
2431 if (k->is_instance_klass()) {
2432 InstanceKlass* ik = InstanceKlass::cast(k);
2433 if (ik->has_final_method()) buf[i++] = 'f';
2434 if (ik->is_rewritten()) buf[i++] = 'W';
2435 if (ik->is_contended()) buf[i++] = 'C';
2436 if (ik->has_been_redefined()) buf[i++] = 'R';
2437 if (ik->in_aot_cache()) buf[i++] = 'S';
2438 }
2439 buf[i++] = '\0';
2440 _st->print("%-7s ", buf);
2441 // klass name
2442 _st->print("%-5s ", k->external_name());
2443 // end
2444 _st->cr();
2445 if (_verbose) {
2446 k->print_on(_st);
2447 }
2448 }
2449
2450 /* jni_id_for for jfieldIds only */
2451 JNIid* InstanceKlass::jni_id_for(int offset) {
2452 MutexLocker ml(JfieldIdCreation_lock);
2453 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2454 if (probe == nullptr) {
2455 // Allocate new static field identifier
2456 probe = new JNIid(this, offset, jni_ids());
2457 set_jni_ids(probe);
2458 }
2459 return probe;
2460 }
2461
2462 u2 InstanceKlass::enclosing_method_data(int offset) const {
2463 const Array<jushort>* const inner_class_list = inner_classes();
2464 if (inner_class_list == nullptr) {
2465 return 0;
2466 }
2467 const int length = inner_class_list->length();
2468 if (length % inner_class_next_offset == 0) {
2469 return 0;
2470 }
2471 const int index = length - enclosing_method_attribute_size;
2472 assert(offset < enclosing_method_attribute_size, "invalid offset");
2473 return inner_class_list->at(index + offset);
2474 }
2475
2476 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2477 u2 method_index) {
2478 Array<jushort>* inner_class_list = inner_classes();
2479 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2480 int length = inner_class_list->length();
2481 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2482 int index = length - enclosing_method_attribute_size;
2483 inner_class_list->at_put(
2484 index + enclosing_method_class_index_offset, class_index);
2485 inner_class_list->at_put(
2486 index + enclosing_method_method_index_offset, method_index);
2487 }
2488 }
2489
2490 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2491 if (method->is_old() && !method->is_obsolete()) {
2492 // If the method passed in is old (but not obsolete), use the current version.
2493 method = method_with_idnum((int)idnum);
2494 assert(method != nullptr, "old and but not obsolete, so should exist");
2495 }
2496 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2497 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2498 return new_id;
2499 }
2500
2501 // Allocate the jmethodID cache.
2502 static jmethodID* create_jmethod_id_cache(size_t size) {
2503 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2504 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2505 // cache size is stored in element[0], other elements offset by one
2506 jmeths[0] = (jmethodID)size;
2507 return jmeths;
2508 }
2509
2510 // When reading outside a lock, use this.
2511 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2512 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2513 }
2514
2515 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2516 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2517 }
2518
2519 // Lookup or create a jmethodID.
2520 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2521 int idnum = method->method_idnum();
2522 jmethodID* jmeths = methods_jmethod_ids_acquire();
2523
2524 // We use a double-check locking idiom here because this cache is
2525 // performance sensitive. In the normal system, this cache only
2526 // transitions from null to non-null which is safe because we use
2527 // release_set_methods_jmethod_ids() to advertise the new cache.
2528 // A partially constructed cache should never be seen by a racing
2529 // thread. We also use release_store() to save a new jmethodID
2530 // in the cache so a partially constructed jmethodID should never be
2531 // seen either. Cache reads of existing jmethodIDs proceed without a
2532 // lock, but cache writes of a new jmethodID requires uniqueness and
2533 // creation of the cache itself requires no leaks so a lock is
2534 // acquired in those two cases.
2535 //
2536 // If the RedefineClasses() API has been used, then this cache grows
2537 // in the redefinition safepoint.
2538
2539 if (jmeths == nullptr) {
2540 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2541 jmeths = _methods_jmethod_ids;
2542 // Still null?
2543 if (jmeths == nullptr) {
2544 size_t size = idnum_allocated_count();
2545 assert(size > (size_t)idnum, "should already have space");
2546 jmeths = create_jmethod_id_cache(size);
2547 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2548
2549 // publish jmeths
2550 release_set_methods_jmethod_ids(jmeths);
2551 return new_id;
2552 }
2553 }
2554
2555 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2556 if (id == nullptr) {
2557 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2558 id = jmeths[idnum + 1];
2559 // Still null?
2560 if (id == nullptr) {
2561 return update_jmethod_id(jmeths, method, idnum);
2562 }
2563 }
2564 return id;
2565 }
2566
2567 void InstanceKlass::update_methods_jmethod_cache() {
2568 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2569 jmethodID* cache = _methods_jmethod_ids;
2570 if (cache != nullptr) {
2571 size_t size = idnum_allocated_count();
2572 size_t old_size = (size_t)cache[0];
2573 if (old_size < size + 1) {
2574 // Allocate a larger one and copy entries to the new one.
2575 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2576 jmethodID* new_cache = create_jmethod_id_cache(size);
2577
2578 for (int i = 1; i <= (int)old_size; i++) {
2579 new_cache[i] = cache[i];
2580 }
2581 _methods_jmethod_ids = new_cache;
2582 FREE_C_HEAP_ARRAY(jmethodID, cache);
2583 }
2584 }
2585 }
2586
2587 // Make a jmethodID for all methods in this class. This makes getting all method
2588 // ids much, much faster with classes with more than 8
2589 // methods, and has a *substantial* effect on performance with jvmti
2590 // code that loads all jmethodIDs for all classes.
2591 void InstanceKlass::make_methods_jmethod_ids() {
2592 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2593 jmethodID* jmeths = _methods_jmethod_ids;
2594 if (jmeths == nullptr) {
2595 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2596 release_set_methods_jmethod_ids(jmeths);
2597 }
2598
2599 int length = methods()->length();
2600 for (int index = 0; index < length; index++) {
2601 Method* m = methods()->at(index);
2602 int idnum = m->method_idnum();
2603 assert(!m->is_old(), "should not have old methods or I'm confused");
2604 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2605 if (!m->is_overpass() && // skip overpasses
2606 id == nullptr) {
2607 id = Method::make_jmethod_id(class_loader_data(), m);
2608 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2609 }
2610 }
2611 }
2612
2613 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2614 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2615 int idnum = method->method_idnum();
2616 jmethodID* jmeths = methods_jmethod_ids_acquire();
2617 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2618 }
2619
2620 inline DependencyContext InstanceKlass::dependencies() {
2621 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2622 return dep_context;
2623 }
2624
2625 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2626 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2627 }
2628
2629 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2630 assert_lock_strong(CodeCache_lock);
2631 dependencies().add_dependent_nmethod(nm);
2632 }
2633
2634 void InstanceKlass::clean_dependency_context() {
2635 dependencies().clean_unloading_dependents();
2636 }
2637
2638 #ifndef PRODUCT
2639 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2640 dependencies().print_dependent_nmethods(verbose);
2641 }
2642
2643 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2644 return dependencies().is_dependent_nmethod(nm);
2645 }
2646 #endif //PRODUCT
2647
2648 void InstanceKlass::clean_weak_instanceklass_links() {
2649 clean_implementors_list();
2650 clean_method_data();
2651 }
2652
2653 void InstanceKlass::clean_implementors_list() {
2654 assert(is_loader_alive(), "this klass should be live");
2655 if (is_interface()) {
2656 assert (ClassUnloading, "only called for ClassUnloading");
2657 for (;;) {
2658 // Use load_acquire due to competing with inserts
2659 InstanceKlass* volatile* iklass = adr_implementor();
2660 assert(iklass != nullptr, "Klass must not be null");
2661 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2662 if (impl != nullptr && !impl->is_loader_alive()) {
2663 // null this field, might be an unloaded instance klass or null
2664 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2665 // Successfully unlinking implementor.
2666 if (log_is_enabled(Trace, class, unload)) {
2667 ResourceMark rm;
2668 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2669 }
2670 return;
2671 }
2672 } else {
2673 return;
2674 }
2675 }
2676 }
2677 }
2678
2679 void InstanceKlass::clean_method_data() {
2680 for (int m = 0; m < methods()->length(); m++) {
2681 MethodData* mdo = methods()->at(m)->method_data();
2682 if (mdo != nullptr) {
2683 mdo->clean_method_data(/*always_clean*/false);
2684 }
2685 }
2686 }
2687
2688 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2689 Klass::metaspace_pointers_do(it);
2690
2691 if (log_is_enabled(Trace, aot)) {
2692 ResourceMark rm;
2693 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2694 }
2695
2696 it->push(&_annotations);
2697 it->push((Klass**)&_array_klasses);
2698 if (!is_rewritten()) {
2699 it->push(&_constants, MetaspaceClosure::_writable);
2700 } else {
2701 it->push(&_constants);
2702 }
2703 it->push(&_inner_classes);
2704 #if INCLUDE_JVMTI
2705 it->push(&_previous_versions);
2706 #endif
2707 #if INCLUDE_CDS
2708 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2709 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2710 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2711 // The length check on the _methods is necessary because classes which don't have any
2712 // methods share the Universe::_the_empty_method_array which is in the RO region.
2713 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2714 // To handle jsr bytecode, new Method* maybe stored into _methods
2715 it->push(&_methods, MetaspaceClosure::_writable);
2716 } else {
2717 #endif
2718 it->push(&_methods);
2719 #if INCLUDE_CDS
2720 }
2721 #endif
2722 it->push(&_default_methods);
2723 it->push(&_local_interfaces);
2724 it->push(&_transitive_interfaces);
2725 it->push(&_method_ordering);
2726 if (!is_rewritten()) {
2727 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2728 } else {
2729 it->push(&_default_vtable_indices);
2730 }
2731
2732 it->push(&_fieldinfo_stream);
2733 it->push(&_fieldinfo_search_table);
2734 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2735 it->push(&_fields_status, MetaspaceClosure::_writable);
2736
2737 if (itable_length() > 0) {
2738 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2739 int method_table_offset_in_words = ioe->offset()/wordSize;
2740 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2741
2742 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2743 / itableOffsetEntry::size();
2744
2745 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2746 if (ioe->interface_klass() != nullptr) {
2747 it->push(ioe->interface_klass_addr());
2748 itableMethodEntry* ime = ioe->first_method_entry(this);
2749 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2750 for (int index = 0; index < n; index ++) {
2751 it->push(ime[index].method_addr());
2752 }
2753 }
2754 }
2755 }
2756
2757 it->push(&_nest_host);
2758 it->push(&_nest_members);
2759 it->push(&_permitted_subclasses);
2760 it->push(&_record_components);
2761 }
2762
2763 #if INCLUDE_CDS
2764 void InstanceKlass::remove_unshareable_info() {
2765 if (is_linked()) {
2766 assert(can_be_verified_at_dumptime(), "must be");
2767 // Remember this so we can avoid walking the hierarchy at runtime.
2768 set_verified_at_dump_time();
2769 }
2770
2771 _misc_flags.set_has_init_deps_processed(false);
2772
2773 Klass::remove_unshareable_info();
2774
2775 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2776 // Classes are attempted to link during dumping and may fail,
2777 // but these classes are still in the dictionary and class list in CLD.
2778 // If the class has failed verification, there is nothing else to remove.
2779 return;
2780 }
2781
2782 // Reset to the 'allocated' state to prevent any premature accessing to
2783 // a shared class at runtime while the class is still being loaded and
2784 // restored. A class' init_state is set to 'loaded' at runtime when it's
2785 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2786 _init_state = allocated;
2787
2788 { // Otherwise this needs to take out the Compile_lock.
2789 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2790 init_implementor();
2791 }
2792
2793 // Call remove_unshareable_info() on other objects that belong to this class, except
2794 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2795 // ArchiveBuilder::make_klasses_shareable(),
2796
2797 for (int i = 0; i < methods()->length(); i++) {
2798 Method* m = methods()->at(i);
2799 m->remove_unshareable_info();
2800 }
2801
2802 // do array classes also.
2803 if (array_klasses() != nullptr) {
2804 array_klasses()->remove_unshareable_info();
2805 }
2806
2807 // These are not allocated from metaspace. They are safe to set to null.
2808 _source_debug_extension = nullptr;
2809 _dep_context = nullptr;
2810 _osr_nmethods_head = nullptr;
2811 #if INCLUDE_JVMTI
2812 _breakpoints = nullptr;
2813 _previous_versions = nullptr;
2814 _cached_class_file = nullptr;
2815 _jvmti_cached_class_field_map = nullptr;
2816 #endif
2817
2818 _init_thread = nullptr;
2819 _methods_jmethod_ids = nullptr;
2820 _jni_ids = nullptr;
2821 _oop_map_cache = nullptr;
2822 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2823 // keep _nest_host
2824 } else {
2825 // clear _nest_host to ensure re-load at runtime
2826 _nest_host = nullptr;
2827 }
2828 init_shared_package_entry();
2829 _dep_context_last_cleaned = 0;
2830 DEBUG_ONLY(_shared_class_load_count = 0);
2831
2832 remove_unshareable_flags();
2833
2834 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2835 }
2836
2837 void InstanceKlass::remove_unshareable_flags() {
2838 // clear all the flags/stats that shouldn't be in the archived version
2839 assert(!is_scratch_class(), "must be");
2840 assert(!has_been_redefined(), "must be");
2841 #if INCLUDE_JVMTI
2842 set_is_being_redefined(false);
2843 #endif
2844 set_has_resolved_methods(false);
2845 }
2846
2847 void InstanceKlass::remove_java_mirror() {
2848 Klass::remove_java_mirror();
2849
2850 // do array classes also.
2851 if (array_klasses() != nullptr) {
2852 array_klasses()->remove_java_mirror();
2853 }
2854 }
2855
2856 void InstanceKlass::init_shared_package_entry() {
2857 assert(CDSConfig::is_dumping_archive(), "must be");
2858 #if !INCLUDE_CDS_JAVA_HEAP
2859 _package_entry = nullptr;
2860 #else
2861 if (CDSConfig::is_dumping_full_module_graph()) {
2862 if (defined_by_other_loaders()) {
2863 _package_entry = nullptr;
2864 } else {
2865 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2866 }
2867 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2868 CDSConfig::is_using_full_module_graph() &&
2869 AOTMetaspace::in_aot_cache(_package_entry)) {
2870 // _package_entry is an archived package in the base archive. Leave it as is.
2871 } else {
2872 _package_entry = nullptr;
2873 }
2874 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2875 #endif
2876 }
2877
2878 void InstanceKlass::compute_has_loops_flag_for_methods() {
2879 Array<Method*>* methods = this->methods();
2880 for (int index = 0; index < methods->length(); ++index) {
2881 Method* m = methods->at(index);
2882 if (!m->is_overpass()) { // work around JDK-8305771
2883 m->compute_has_loops_flag();
2884 }
2885 }
2886 }
2887
2888 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2889 PackageEntry* pkg_entry, TRAPS) {
2890 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2891 // before the InstanceKlass is added to the SystemDictionary. Make
2892 // sure the current state is <loaded.
2893 assert(!is_loaded(), "invalid init state");
2894 assert(!shared_loading_failed(), "Must not try to load failed class again");
2895 set_package(loader_data, pkg_entry, CHECK);
2896 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2897
2898 Array<Method*>* methods = this->methods();
2899 int num_methods = methods->length();
2900 for (int index = 0; index < num_methods; ++index) {
2901 methods->at(index)->restore_unshareable_info(CHECK);
2902 }
2903 #if INCLUDE_JVMTI
2904 if (JvmtiExport::has_redefined_a_class()) {
2905 // Reinitialize vtable because RedefineClasses may have changed some
2906 // entries in this vtable for super classes so the CDS vtable might
2907 // point to old or obsolete entries. RedefineClasses doesn't fix up
2908 // vtables in the shared system dictionary, only the main one.
2909 // It also redefines the itable too so fix that too.
2910 // First fix any default methods that point to a super class that may
2911 // have been redefined.
2912 bool trace_name_printed = false;
2913 adjust_default_methods(&trace_name_printed);
2914 if (verified_at_dump_time()) {
2915 // Initialize vtable and itable for classes which can be verified at dump time.
2916 // Unlinked classes such as old classes with major version < 50 cannot be verified
2917 // at dump time.
2918 vtable().initialize_vtable();
2919 itable().initialize_itable();
2920 }
2921 }
2922 #endif // INCLUDE_JVMTI
2923
2924 // restore constant pool resolved references
2925 constants()->restore_unshareable_info(CHECK);
2926
2927 if (array_klasses() != nullptr) {
2928 // To get a consistent list of classes we need MultiArray_lock to ensure
2929 // array classes aren't observed while they are being restored.
2930 RecursiveLocker rl(MultiArray_lock, THREAD);
2931 assert(this == array_klasses()->bottom_klass(), "sanity");
2932 // Array classes have null protection domain.
2933 // --> see ArrayKlass::complete_create_array_klass()
2934 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2935 }
2936
2937 // Initialize @ValueBased class annotation if not already set in the archived klass.
2938 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2939 set_is_value_based();
2940 }
2941
2942 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2943 }
2944
2945 bool InstanceKlass::can_be_verified_at_dumptime() const {
2946 if (AOTMetaspace::in_aot_cache(this)) {
2947 // This is a class that was dumped into the base archive, so we know
2948 // it was verified at dump time.
2949 return true;
2950 }
2951
2952 if (CDSConfig::is_preserving_verification_constraints()) {
2953 return true;
2954 }
2955
2956 if (CDSConfig::is_old_class_for_verifier(this)) {
2957 // The old verifier does not save verification constraints, so at run time
2958 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
2959 return false;
2960 }
2961 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
2962 return false;
2963 }
2964 Array<InstanceKlass*>* interfaces = local_interfaces();
2965 int len = interfaces->length();
2966 for (int i = 0; i < len; i++) {
2967 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2968 return false;
2969 }
2970 }
2971 return true;
2972 }
2973
2974 #endif // INCLUDE_CDS
2975
2976 #if INCLUDE_JVMTI
2977 static void clear_all_breakpoints(Method* m) {
2978 m->clear_all_breakpoints();
2979 }
2980 #endif
2981
2982 void InstanceKlass::unload_class(InstanceKlass* ik) {
2983
2984 if (ik->is_scratch_class()) {
2985 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2986 return;
2987 }
2988 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2989
2990 // Release dependencies.
2991 ik->dependencies().remove_all_dependents();
2992
2993 // notify the debugger
2994 if (JvmtiExport::should_post_class_unload()) {
2995 JvmtiExport::post_class_unload(ik);
2996 }
2997
2998 // notify ClassLoadingService of class unload
2999 ClassLoadingService::notify_class_unloaded(ik);
3000
3001 SystemDictionaryShared::handle_class_unloading(ik);
3002
3003 if (log_is_enabled(Info, class, unload)) {
3004 ResourceMark rm;
3005 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3006 }
3007
3008 Events::log_class_unloading(Thread::current(), ik);
3009
3010 #if INCLUDE_JFR
3011 assert(ik != nullptr, "invariant");
3012 EventClassUnload event;
3013 event.set_unloadedClass(ik);
3014 event.set_definingClassLoader(ik->class_loader_data());
3015 event.commit();
3016 #endif
3017 }
3018
3019 static void method_release_C_heap_structures(Method* m) {
3020 m->release_C_heap_structures();
3021 }
3022
3023 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3024 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3025 // Clean up C heap
3026 Klass::release_C_heap_structures();
3027
3028 // Deallocate and call destructors for MDO mutexes
3029 if (release_sub_metadata) {
3030 methods_do(method_release_C_heap_structures);
3031 }
3032
3033 // Deallocate oop map cache
3034 if (_oop_map_cache != nullptr) {
3035 delete _oop_map_cache;
3036 _oop_map_cache = nullptr;
3037 }
3038
3039 // Deallocate JNI identifiers for jfieldIDs
3040 JNIid::deallocate(jni_ids());
3041 set_jni_ids(nullptr);
3042
3043 jmethodID* jmeths = _methods_jmethod_ids;
3044 if (jmeths != nullptr) {
3045 release_set_methods_jmethod_ids(nullptr);
3046 FreeHeap(jmeths);
3047 }
3048
3049 assert(_dep_context == nullptr,
3050 "dependencies should already be cleaned");
3051
3052 #if INCLUDE_JVMTI
3053 // Deallocate breakpoint records
3054 if (breakpoints() != nullptr) {
3055 methods_do(clear_all_breakpoints);
3056 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3057 }
3058
3059 // deallocate the cached class file
3060 if (_cached_class_file != nullptr) {
3061 os::free(_cached_class_file);
3062 _cached_class_file = nullptr;
3063 }
3064 #endif
3065
3066 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3067
3068 if (release_sub_metadata) {
3069 constants()->release_C_heap_structures();
3070 }
3071 }
3072
3073 // The constant pool is on stack if any of the methods are executing or
3074 // referenced by handles.
3075 bool InstanceKlass::on_stack() const {
3076 return _constants->on_stack();
3077 }
3078
3079 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3080 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3081 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3082
3083 // minor and major version numbers of class file
3084 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3085 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3086 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3087 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3088
3089 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3090 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3091 if (ik->constants()->version() == version) {
3092 return ik;
3093 }
3094 }
3095 return nullptr;
3096 }
3097
3098 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3099 if (array == nullptr) {
3100 _source_debug_extension = nullptr;
3101 } else {
3102 // Adding one to the attribute length in order to store a null terminator
3103 // character could cause an overflow because the attribute length is
3104 // already coded with an u4 in the classfile, but in practice, it's
3105 // unlikely to happen.
3106 assert((length+1) > length, "Overflow checking");
3107 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3108 for (int i = 0; i < length; i++) {
3109 sde[i] = array[i];
3110 }
3111 sde[length] = '\0';
3112 _source_debug_extension = sde;
3113 }
3114 }
3115
3116 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3117 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3118 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3119
3120 const char* InstanceKlass::signature_name() const {
3121
3122 // Get the internal name as a c string
3123 const char* src = (const char*) (name()->as_C_string());
3124 const int src_length = (int)strlen(src);
3125
3126 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3127
3128 // Add L as type indicator
3129 int dest_index = 0;
3130 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3131
3132 // Add the actual class name
3133 for (int src_index = 0; src_index < src_length; ) {
3134 dest[dest_index++] = src[src_index++];
3135 }
3136
3137 if (is_hidden()) { // Replace the last '+' with a '.'.
3138 for (int index = (int)src_length; index > 0; index--) {
3139 if (dest[index] == '+') {
3140 dest[index] = JVM_SIGNATURE_DOT;
3141 break;
3142 }
3143 }
3144 }
3145
3146 // Add the semicolon and the null
3147 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3148 dest[dest_index] = '\0';
3149 return dest;
3150 }
3151
3152 ModuleEntry* InstanceKlass::module() const {
3153 if (is_hidden() &&
3154 in_unnamed_package() &&
3155 class_loader_data()->has_class_mirror_holder()) {
3156 // For a non-strong hidden class defined to an unnamed package,
3157 // its (class held) CLD will not have an unnamed module created for it.
3158 // Two choices to find the correct ModuleEntry:
3159 // 1. If hidden class is within a nest, use nest host's module
3160 // 2. Find the unnamed module off from the class loader
3161 // For now option #2 is used since a nest host is not set until
3162 // after the instance class is created in jvm_lookup_define_class().
3163 if (class_loader_data()->is_boot_class_loader_data()) {
3164 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3165 } else {
3166 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3167 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3168 return java_lang_Module::module_entry(module);
3169 }
3170 }
3171
3172 // Class is in a named package
3173 if (!in_unnamed_package()) {
3174 return _package_entry->module();
3175 }
3176
3177 // Class is in an unnamed package, return its loader's unnamed module
3178 return class_loader_data()->unnamed_module();
3179 }
3180
3181 bool InstanceKlass::in_javabase_module() const {
3182 return module()->name() == vmSymbols::java_base();
3183 }
3184
3185 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3186
3187 // ensure java/ packages only loaded by boot or platform builtin loaders
3188 // not needed for shared class since CDS does not archive prohibited classes.
3189 if (!in_aot_cache()) {
3190 check_prohibited_package(name(), loader_data, CHECK);
3191 }
3192
3193 if (in_aot_cache() && _package_entry != nullptr) {
3194 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3195 // we can use the saved package
3196 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3197 return;
3198 } else {
3199 _package_entry = nullptr;
3200 }
3201 }
3202
3203 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3204 // it returns, so we need to decrement it when the current function exits.
3205 TempNewSymbol from_class_name =
3206 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3207
3208 Symbol* pkg_name;
3209 if (pkg_entry != nullptr) {
3210 pkg_name = pkg_entry->name();
3211 } else {
3212 pkg_name = from_class_name;
3213 }
3214
3215 if (pkg_name != nullptr && loader_data != nullptr) {
3216
3217 // Find in class loader's package entry table.
3218 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3219
3220 // If the package name is not found in the loader's package
3221 // entry table, it is an indication that the package has not
3222 // been defined. Consider it defined within the unnamed module.
3223 if (_package_entry == nullptr) {
3224
3225 if (!ModuleEntryTable::javabase_defined()) {
3226 // Before java.base is defined during bootstrapping, define all packages in
3227 // the java.base module. If a non-java.base package is erroneously placed
3228 // in the java.base module it will be caught later when java.base
3229 // is defined by ModuleEntryTable::verify_javabase_packages check.
3230 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3231 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3232 } else {
3233 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3234 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3235 }
3236
3237 // A package should have been successfully created
3238 DEBUG_ONLY(ResourceMark rm(THREAD));
3239 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3240 name()->as_C_string(), loader_data->loader_name_and_id());
3241 }
3242
3243 if (log_is_enabled(Debug, module)) {
3244 ResourceMark rm(THREAD);
3245 ModuleEntry* m = _package_entry->module();
3246 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3247 external_name(),
3248 pkg_name->as_C_string(),
3249 loader_data->loader_name_and_id(),
3250 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3251 }
3252 } else {
3253 ResourceMark rm(THREAD);
3254 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3255 external_name(),
3256 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3257 UNNAMED_MODULE);
3258 }
3259 }
3260
3261 // Function set_classpath_index ensures that for a non-null _package_entry
3262 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3263 // It then sets the classpath_index in the package entry record.
3264 //
3265 // The classpath_index field is used to find the entry on the boot loader class
3266 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3267 // in an unnamed module. It is also used to indicate (for all packages whose
3268 // classes are loaded by the boot loader) that at least one of the package's
3269 // classes has been loaded.
3270 void InstanceKlass::set_classpath_index(s2 path_index) {
3271 if (_package_entry != nullptr) {
3272 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3273 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3274 assert(path_index != -1, "Unexpected classpath_index");
3275 _package_entry->set_classpath_index(path_index);
3276 }
3277 }
3278
3279 // different versions of is_same_class_package
3280
3281 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3282 oop classloader1 = this->class_loader();
3283 PackageEntry* classpkg1 = this->package();
3284 if (class2->is_objArray_klass()) {
3285 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3286 }
3287
3288 oop classloader2;
3289 PackageEntry* classpkg2;
3290 if (class2->is_instance_klass()) {
3291 classloader2 = class2->class_loader();
3292 classpkg2 = class2->package();
3293 } else {
3294 assert(class2->is_typeArray_klass(), "should be type array");
3295 classloader2 = nullptr;
3296 classpkg2 = nullptr;
3297 }
3298
3299 // Same package is determined by comparing class loader
3300 // and package entries. Both must be the same. This rule
3301 // applies even to classes that are defined in the unnamed
3302 // package, they still must have the same class loader.
3303 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3304 return true;
3305 }
3306
3307 return false;
3308 }
3309
3310 // return true if this class and other_class are in the same package. Classloader
3311 // and classname information is enough to determine a class's package
3312 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3313 const Symbol* other_class_name) const {
3314 if (class_loader() != other_class_loader) {
3315 return false;
3316 }
3317 if (name()->fast_compare(other_class_name) == 0) {
3318 return true;
3319 }
3320
3321 {
3322 ResourceMark rm;
3323
3324 bool bad_class_name = false;
3325 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3326 if (bad_class_name) {
3327 return false;
3328 }
3329 // Check that package_from_class_name() returns null, not "", if there is no package.
3330 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3331
3332 const Symbol* const this_package_name =
3333 this->package() != nullptr ? this->package()->name() : nullptr;
3334
3335 if (this_package_name == nullptr || other_pkg == nullptr) {
3336 // One of the two doesn't have a package. Only return true if the other
3337 // one also doesn't have a package.
3338 return this_package_name == other_pkg;
3339 }
3340
3341 // Check if package is identical
3342 return this_package_name->fast_compare(other_pkg) == 0;
3343 }
3344 }
3345
3346 static bool is_prohibited_package_slow(Symbol* class_name) {
3347 // Caller has ResourceMark
3348 int length;
3349 jchar* unicode = class_name->as_unicode(length);
3350 return (length >= 5 &&
3351 unicode[0] == 'j' &&
3352 unicode[1] == 'a' &&
3353 unicode[2] == 'v' &&
3354 unicode[3] == 'a' &&
3355 unicode[4] == '/');
3356 }
3357
3358 // Only boot and platform class loaders can define classes in "java/" packages.
3359 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3360 ClassLoaderData* loader_data,
3361 TRAPS) {
3362 if (!loader_data->is_boot_class_loader_data() &&
3363 !loader_data->is_platform_class_loader_data() &&
3364 class_name != nullptr && class_name->utf8_length() >= 5) {
3365 ResourceMark rm(THREAD);
3366 bool prohibited;
3367 const u1* base = class_name->base();
3368 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3369 prohibited = is_prohibited_package_slow(class_name);
3370 } else {
3371 char* name = class_name->as_C_string();
3372 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3373 }
3374 if (prohibited) {
3375 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3376 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3377 char* name = pkg_name->as_C_string();
3378 const char* class_loader_name = loader_data->loader_name_and_id();
3379 StringUtils::replace_no_expand(name, "/", ".");
3380 const char* msg_text1 = "Class loader (instance of): ";
3381 const char* msg_text2 = " tried to load prohibited package name: ";
3382 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3383 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3384 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3385 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3386 }
3387 }
3388 return;
3389 }
3390
3391 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3392 constantPoolHandle i_cp(THREAD, constants());
3393 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3394 int ioff = iter.inner_class_info_index();
3395 if (ioff != 0) {
3396 // Check to see if the name matches the class we're looking for
3397 // before attempting to find the class.
3398 if (i_cp->klass_name_at_matches(this, ioff)) {
3399 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3400 if (this == inner_klass) {
3401 *ooff = iter.outer_class_info_index();
3402 *noff = iter.inner_name_index();
3403 return true;
3404 }
3405 }
3406 }
3407 }
3408 return false;
3409 }
3410
3411 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3412 InstanceKlass* outer_klass = nullptr;
3413 *inner_is_member = false;
3414 int ooff = 0, noff = 0;
3415 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3416 if (has_inner_classes_attr) {
3417 constantPoolHandle i_cp(THREAD, constants());
3418 if (ooff != 0) {
3419 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3420 if (!ok->is_instance_klass()) {
3421 // If the outer class is not an instance klass then it cannot have
3422 // declared any inner classes.
3423 ResourceMark rm(THREAD);
3424 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3425 Exceptions::fthrow(
3426 THREAD_AND_LOCATION,
3427 vmSymbols::java_lang_IncompatibleClassChangeError(),
3428 "%s and %s disagree on InnerClasses attribute",
3429 ok->external_name(),
3430 external_name());
3431 return nullptr;
3432 }
3433 outer_klass = InstanceKlass::cast(ok);
3434 *inner_is_member = true;
3435 }
3436 if (nullptr == outer_klass) {
3437 // It may be a local class; try for that.
3438 int encl_method_class_idx = enclosing_method_class_index();
3439 if (encl_method_class_idx != 0) {
3440 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3441 outer_klass = InstanceKlass::cast(ok);
3442 *inner_is_member = false;
3443 }
3444 }
3445 }
3446
3447 // If no inner class attribute found for this class.
3448 if (nullptr == outer_klass) return nullptr;
3449
3450 // Throws an exception if outer klass has not declared k as an inner klass
3451 // We need evidence that each klass knows about the other, or else
3452 // the system could allow a spoof of an inner class to gain access rights.
3453 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3454 return outer_klass;
3455 }
3456
3457 u2 InstanceKlass::compute_modifier_flags() const {
3458 u2 access = access_flags().as_unsigned_short();
3459
3460 // But check if it happens to be member class.
3461 InnerClassesIterator iter(this);
3462 for (; !iter.done(); iter.next()) {
3463 int ioff = iter.inner_class_info_index();
3464 // Inner class attribute can be zero, skip it.
3465 // Strange but true: JVM spec. allows null inner class refs.
3466 if (ioff == 0) continue;
3467
3468 // only look at classes that are already loaded
3469 // since we are looking for the flags for our self.
3470 Symbol* inner_name = constants()->klass_name_at(ioff);
3471 if (name() == inner_name) {
3472 // This is really a member class.
3473 access = iter.inner_access_flags();
3474 break;
3475 }
3476 }
3477 // Remember to strip ACC_SUPER bit
3478 return (access & (~JVM_ACC_SUPER));
3479 }
3480
3481 jint InstanceKlass::jvmti_class_status() const {
3482 jint result = 0;
3483
3484 if (is_linked()) {
3485 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3486 }
3487
3488 if (is_initialized()) {
3489 assert(is_linked(), "Class status is not consistent");
3490 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3491 }
3492 if (is_in_error_state()) {
3493 result |= JVMTI_CLASS_STATUS_ERROR;
3494 }
3495 return result;
3496 }
3497
3498 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3499 bool implements_interface; // initialized by method_at_itable_or_null
3500 Method* m = method_at_itable_or_null(holder, index,
3501 implements_interface); // out parameter
3502 if (m != nullptr) {
3503 assert(implements_interface, "sanity");
3504 return m;
3505 } else if (implements_interface) {
3506 // Throw AbstractMethodError since corresponding itable slot is empty.
3507 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3508 } else {
3509 // If the interface isn't implemented by the receiver class,
3510 // the VM should throw IncompatibleClassChangeError.
3511 ResourceMark rm(THREAD);
3512 stringStream ss;
3513 bool same_module = (module() == holder->module());
3514 ss.print("Receiver class %s does not implement "
3515 "the interface %s defining the method to be called "
3516 "(%s%s%s)",
3517 external_name(), holder->external_name(),
3518 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3519 (same_module) ? "" : "; ",
3520 (same_module) ? "" : holder->class_in_module_of_loader());
3521 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3522 }
3523 }
3524
3525 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3526 klassItable itable(this);
3527 for (int i = 0; i < itable.size_offset_table(); i++) {
3528 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3529 if (offset_entry->interface_klass() == holder) {
3530 implements_interface = true;
3531 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3532 Method* m = ime[index].method();
3533 return m;
3534 }
3535 }
3536 implements_interface = false;
3537 return nullptr; // offset entry not found
3538 }
3539
3540 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3541 assert(is_linked(), "required");
3542 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3543 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3544
3545 int vtable_index = Method::invalid_vtable_index;
3546 Symbol* name = intf_method->name();
3547 Symbol* signature = intf_method->signature();
3548
3549 // First check in default method array
3550 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3551 int index = find_method_index(default_methods(),
3552 name, signature,
3553 Klass::OverpassLookupMode::find,
3554 Klass::StaticLookupMode::find,
3555 Klass::PrivateLookupMode::find);
3556 if (index >= 0) {
3557 vtable_index = default_vtable_indices()->at(index);
3558 }
3559 }
3560 if (vtable_index == Method::invalid_vtable_index) {
3561 // get vtable_index for miranda methods
3562 klassVtable vt = vtable();
3563 vtable_index = vt.index_of_miranda(name, signature);
3564 }
3565 return vtable_index;
3566 }
3567
3568 #if INCLUDE_JVMTI
3569 // update default_methods for redefineclasses for methods that are
3570 // not yet in the vtable due to concurrent subclass define and superinterface
3571 // redefinition
3572 // Note: those in the vtable, should have been updated via adjust_method_entries
3573 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3574 // search the default_methods for uses of either obsolete or EMCP methods
3575 if (default_methods() != nullptr) {
3576 for (int index = 0; index < default_methods()->length(); index ++) {
3577 Method* old_method = default_methods()->at(index);
3578 if (old_method == nullptr || !old_method->is_old()) {
3579 continue; // skip uninteresting entries
3580 }
3581 assert(!old_method->is_deleted(), "default methods may not be deleted");
3582 Method* new_method = old_method->get_new_method();
3583 default_methods()->at_put(index, new_method);
3584
3585 if (log_is_enabled(Info, redefine, class, update)) {
3586 ResourceMark rm;
3587 if (!(*trace_name_printed)) {
3588 log_info(redefine, class, update)
3589 ("adjust: klassname=%s default methods from name=%s",
3590 external_name(), old_method->method_holder()->external_name());
3591 *trace_name_printed = true;
3592 }
3593 log_debug(redefine, class, update, vtables)
3594 ("default method update: %s(%s) ",
3595 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3596 }
3597 }
3598 }
3599 }
3600 #endif // INCLUDE_JVMTI
3601
3602 // On-stack replacement stuff
3603 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3604 assert_lock_strong(NMethodState_lock);
3605 #ifndef PRODUCT
3606 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3607 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3608 "redundant OSR recompilation detected. memory leak in CodeCache!");
3609 #endif
3610 // only one compilation can be active
3611 assert(n->is_osr_method(), "wrong kind of nmethod");
3612 n->set_osr_link(osr_nmethods_head());
3613 set_osr_nmethods_head(n);
3614 // Raise the highest osr level if necessary
3615 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3616
3617 // Get rid of the osr methods for the same bci that have lower levels.
3618 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3619 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3620 if (inv != nullptr && inv->is_in_use()) {
3621 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3622 }
3623 }
3624 }
3625
3626 // Remove osr nmethod from the list. Return true if found and removed.
3627 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3628 // This is a short non-blocking critical region, so the no safepoint check is ok.
3629 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3630 assert(n->is_osr_method(), "wrong kind of nmethod");
3631 nmethod* last = nullptr;
3632 nmethod* cur = osr_nmethods_head();
3633 int max_level = CompLevel_none; // Find the max comp level excluding n
3634 Method* m = n->method();
3635 // Search for match
3636 bool found = false;
3637 while(cur != nullptr && cur != n) {
3638 if (m == cur->method()) {
3639 // Find max level before n
3640 max_level = MAX2(max_level, cur->comp_level());
3641 }
3642 last = cur;
3643 cur = cur->osr_link();
3644 }
3645 nmethod* next = nullptr;
3646 if (cur == n) {
3647 found = true;
3648 next = cur->osr_link();
3649 if (last == nullptr) {
3650 // Remove first element
3651 set_osr_nmethods_head(next);
3652 } else {
3653 last->set_osr_link(next);
3654 }
3655 }
3656 n->set_osr_link(nullptr);
3657 cur = next;
3658 while (cur != nullptr) {
3659 // Find max level after n
3660 if (m == cur->method()) {
3661 max_level = MAX2(max_level, cur->comp_level());
3662 }
3663 cur = cur->osr_link();
3664 }
3665 m->set_highest_osr_comp_level(max_level);
3666 return found;
3667 }
3668
3669 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3670 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3671 nmethod* osr = osr_nmethods_head();
3672 int found = 0;
3673 while (osr != nullptr) {
3674 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3675 if (osr->method() == m) {
3676 deopt_scope->mark(osr);
3677 found++;
3678 }
3679 osr = osr->osr_link();
3680 }
3681 return found;
3682 }
3683
3684 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3685 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3686 nmethod* osr = osr_nmethods_head();
3687 nmethod* best = nullptr;
3688 while (osr != nullptr) {
3689 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3690 // There can be a time when a c1 osr method exists but we are waiting
3691 // for a c2 version. When c2 completes its osr nmethod we will trash
3692 // the c1 version and only be able to find the c2 version. However
3693 // while we overflow in the c1 code at back branches we don't want to
3694 // try and switch to the same code as we are already running
3695
3696 if (osr->method() == m &&
3697 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3698 if (match_level) {
3699 if (osr->comp_level() == comp_level) {
3700 // Found a match - return it.
3701 return osr;
3702 }
3703 } else {
3704 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3705 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3706 // Found the best possible - return it.
3707 return osr;
3708 }
3709 best = osr;
3710 }
3711 }
3712 }
3713 osr = osr->osr_link();
3714 }
3715
3716 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3717 if (best != nullptr && best->comp_level() >= comp_level) {
3718 return best;
3719 }
3720 return nullptr;
3721 }
3722
3723 // -----------------------------------------------------------------------------------------------------
3724 // Printing
3725
3726 #define BULLET " - "
3727
3728 static const char* state_names[] = {
3729 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3730 };
3731
3732 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3733 for (int i = 0; i < len; i++) {
3734 intptr_t e = start[i];
3735 st->print("%d : " INTPTR_FORMAT, i, e);
3736 if (MetaspaceObj::is_valid((Metadata*)e)) {
3737 st->print(" ");
3738 ((Metadata*)e)->print_value_on(st);
3739 }
3740 st->cr();
3741 }
3742 }
3743
3744 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3745 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3746 }
3747
3748 const char* InstanceKlass::init_state_name() const {
3749 return state_names[init_state()];
3750 }
3751
3752 const char* InstanceKlass::state2name(ClassState s) {
3753 return state_names[s];
3754 }
3755
3756 void InstanceKlass::print_on(outputStream* st) const {
3757 assert(is_klass(), "must be klass");
3758 Klass::print_on(st);
3759
3760 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3761 st->print(BULLET"klass size: %d", size()); st->cr();
3762 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3763 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3764 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3765 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3766 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3767 st->print(BULLET"sub: ");
3768 Klass* sub = subklass();
3769 int n;
3770 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3771 if (n < MaxSubklassPrintSize) {
3772 sub->print_value_on(st);
3773 st->print(" ");
3774 }
3775 }
3776 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3777 st->cr();
3778
3779 if (is_interface()) {
3780 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3781 if (nof_implementors() == 1) {
3782 st->print_cr(BULLET"implementor: ");
3783 st->print(" ");
3784 implementor()->print_value_on(st);
3785 st->cr();
3786 }
3787 }
3788
3789 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3790 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3791 if (Verbose || WizardMode) {
3792 Array<Method*>* method_array = methods();
3793 for (int i = 0; i < method_array->length(); i++) {
3794 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3795 }
3796 }
3797 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3798 if (default_methods() != nullptr) {
3799 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3800 if (Verbose) {
3801 Array<Method*>* method_array = default_methods();
3802 for (int i = 0; i < method_array->length(); i++) {
3803 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3804 }
3805 }
3806 }
3807 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3808 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3809 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3810
3811 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3812
3813 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3814 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3815
3816 if (secondary_supers() != nullptr) {
3817 if (Verbose) {
3818 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3819 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3820 for (int i = 0; i < _secondary_supers->length(); i++) {
3821 ResourceMark rm; // for external_name()
3822 Klass* secondary_super = _secondary_supers->at(i);
3823 st->print(BULLET"%2d:", i);
3824 if (is_hashed) {
3825 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3826 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3827 st->print(" dist:%02d:", distance);
3828 }
3829 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3830 }
3831 }
3832 }
3833 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3834
3835 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3836 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3837 if (source_debug_extension() != nullptr) {
3838 st->print(BULLET"source debug extension: ");
3839 st->print("%s", source_debug_extension());
3840 st->cr();
3841 }
3842 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3843 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3844 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3845 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3846 {
3847 bool have_pv = false;
3848 // previous versions are linked together through the InstanceKlass
3849 for (InstanceKlass* pv_node = previous_versions();
3850 pv_node != nullptr;
3851 pv_node = pv_node->previous_versions()) {
3852 if (!have_pv)
3853 st->print(BULLET"previous version: ");
3854 have_pv = true;
3855 pv_node->constants()->print_value_on(st);
3856 }
3857 if (have_pv) st->cr();
3858 }
3859
3860 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3861 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3862 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3863 print_on_maybe_null(st, BULLET"record components: ", record_components());
3864 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3865 if (java_mirror() != nullptr) {
3866 st->print(BULLET"java mirror: ");
3867 java_mirror()->print_value_on(st);
3868 st->cr();
3869 } else {
3870 st->print_cr(BULLET"java mirror: null");
3871 }
3872 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3873 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3874 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3875 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3876 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3877
3878 FieldPrinter print_static_field(st);
3879 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3880 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3881 FieldPrinter print_nonstatic_field(st);
3882 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3883 ik->print_nonstatic_fields(&print_nonstatic_field);
3884
3885 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3886 OopMapBlock* map = start_of_nonstatic_oop_maps();
3887 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3888 while (map < end_map) {
3889 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3890 map++;
3891 }
3892 st->cr();
3893
3894 if (fieldinfo_search_table() != nullptr) {
3895 st->print_cr(BULLET"---- field info search table:");
3896 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
3897 }
3898 }
3899
3900 void InstanceKlass::print_value_on(outputStream* st) const {
3901 assert(is_klass(), "must be klass");
3902 if (Verbose || WizardMode) access_flags().print_on(st);
3903 name()->print_value_on(st);
3904 }
3905
3906 void FieldPrinter::do_field(fieldDescriptor* fd) {
3907 _st->print(BULLET);
3908 if (_obj == nullptr) {
3909 fd->print_on(_st);
3910 _st->cr();
3911 } else {
3912 fd->print_on_for(_st, _obj);
3913 _st->cr();
3914 }
3915 }
3916
3917
3918 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3919 Klass::oop_print_on(obj, st);
3920
3921 if (this == vmClasses::String_klass()) {
3922 typeArrayOop value = java_lang_String::value(obj);
3923 juint length = java_lang_String::length(obj);
3924 if (value != nullptr &&
3925 value->is_typeArray() &&
3926 length <= (juint) value->length()) {
3927 st->print(BULLET"string: ");
3928 java_lang_String::print(obj, st);
3929 st->cr();
3930 }
3931 }
3932
3933 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3934 FieldPrinter print_field(st, obj);
3935 print_nonstatic_fields(&print_field);
3936
3937 if (this == vmClasses::Class_klass()) {
3938 st->print(BULLET"signature: ");
3939 java_lang_Class::print_signature(obj, st);
3940 st->cr();
3941 Klass* real_klass = java_lang_Class::as_Klass(obj);
3942 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3943 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3944 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3945 }
3946 } else if (this == vmClasses::MethodType_klass()) {
3947 st->print(BULLET"signature: ");
3948 java_lang_invoke_MethodType::print_signature(obj, st);
3949 st->cr();
3950 }
3951 }
3952
3953 #ifndef PRODUCT
3954
3955 bool InstanceKlass::verify_itable_index(int i) {
3956 int method_count = klassItable::method_count_for_interface(this);
3957 assert(i >= 0 && i < method_count, "index out of bounds");
3958 return true;
3959 }
3960
3961 #endif //PRODUCT
3962
3963 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3964 st->print("a ");
3965 name()->print_value_on(st);
3966 obj->print_address_on(st);
3967 if (this == vmClasses::String_klass()
3968 && java_lang_String::value(obj) != nullptr) {
3969 ResourceMark rm;
3970 int len = java_lang_String::length(obj);
3971 int plen = (len < 24 ? len : 12);
3972 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3973 st->print(" = \"%s\"", str);
3974 if (len > plen)
3975 st->print("...[%d]", len);
3976 } else if (this == vmClasses::Class_klass()) {
3977 Klass* k = java_lang_Class::as_Klass(obj);
3978 st->print(" = ");
3979 if (k != nullptr) {
3980 k->print_value_on(st);
3981 } else {
3982 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3983 st->print("%s", tname ? tname : "type?");
3984 }
3985 } else if (this == vmClasses::MethodType_klass()) {
3986 st->print(" = ");
3987 java_lang_invoke_MethodType::print_signature(obj, st);
3988 } else if (java_lang_boxing_object::is_instance(obj)) {
3989 st->print(" = ");
3990 java_lang_boxing_object::print(obj, st);
3991 } else if (this == vmClasses::LambdaForm_klass()) {
3992 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3993 if (vmentry != nullptr) {
3994 st->print(" => ");
3995 vmentry->print_value_on(st);
3996 }
3997 } else if (this == vmClasses::MemberName_klass()) {
3998 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3999 if (vmtarget != nullptr) {
4000 st->print(" = ");
4001 vmtarget->print_value_on(st);
4002 } else {
4003 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4004 oop name = java_lang_invoke_MemberName::name(obj);
4005 if (clazz != nullptr) {
4006 clazz->print_value_on(st);
4007 } else {
4008 st->print("null");
4009 }
4010 st->print(".");
4011 if (name != nullptr) {
4012 name->print_value_on(st);
4013 } else {
4014 st->print("null");
4015 }
4016 }
4017 }
4018 }
4019
4020 const char* InstanceKlass::internal_name() const {
4021 return external_name();
4022 }
4023
4024 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4025 const ModuleEntry* module_entry,
4026 const ClassFileStream* cfs) const {
4027
4028 if (ClassListWriter::is_enabled()) {
4029 ClassListWriter::write(this, cfs);
4030 }
4031
4032 print_class_load_helper(loader_data, module_entry, cfs);
4033 print_class_load_cause_logging();
4034 }
4035
4036 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4037 const ModuleEntry* module_entry,
4038 const ClassFileStream* cfs) const {
4039
4040 if (!log_is_enabled(Info, class, load)) {
4041 return;
4042 }
4043
4044 ResourceMark rm;
4045 LogMessage(class, load) msg;
4046 stringStream info_stream;
4047
4048 // Name and class hierarchy info
4049 info_stream.print("%s", external_name());
4050
4051 // Source
4052 if (cfs != nullptr) {
4053 if (cfs->source() != nullptr) {
4054 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4055 if (module_name != nullptr) {
4056 // When the boot loader created the stream, it didn't know the module name
4057 // yet. Let's format it now.
4058 if (cfs->from_boot_loader_modules_image()) {
4059 info_stream.print(" source: jrt:/%s", module_name);
4060 } else {
4061 info_stream.print(" source: %s", cfs->source());
4062 }
4063 } else {
4064 info_stream.print(" source: %s", cfs->source());
4065 }
4066 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4067 Thread* current = Thread::current();
4068 Klass* caller = current->is_Java_thread() ?
4069 JavaThread::cast(current)->security_get_caller_class(1):
4070 nullptr;
4071 // caller can be null, for example, during a JVMTI VM_Init hook
4072 if (caller != nullptr) {
4073 info_stream.print(" source: instance of %s", caller->external_name());
4074 } else {
4075 // source is unknown
4076 }
4077 } else {
4078 oop class_loader = loader_data->class_loader();
4079 info_stream.print(" source: %s", class_loader->klass()->external_name());
4080 }
4081 } else {
4082 assert(this->in_aot_cache(), "must be");
4083 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
4084 info_stream.print(" source: shared objects file (top)");
4085 } else {
4086 info_stream.print(" source: shared objects file");
4087 }
4088 }
4089
4090 info_stream.print(" loader:");
4091 #if INCLUDE_CDS
4092 if (in_aot_cache()) {
4093 info_stream.print(" %s", SystemDictionaryShared::loader_type_for_shared_class((Klass*)this));
4094 } else
4095 #endif
4096 if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4097 info_stream.print(" boot_loader");
4098 } else {
4099 oop class_loader = loader_data->class_loader();
4100 if (class_loader != nullptr) {
4101 info_stream.print(" %s", class_loader->klass()->external_name());
4102 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4103 if (cl_name_and_id != nullptr) {
4104 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4105 }
4106 } else {
4107 info_stream.print(" null");
4108 }
4109 }
4110 msg.info("%s", info_stream.as_string());
4111
4112 if (log_is_enabled(Debug, class, load)) {
4113 stringStream debug_stream;
4114
4115 // Class hierarchy info
4116 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4117 p2i(this), p2i(super()));
4118
4119 // Interfaces
4120 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4121 debug_stream.print(" interfaces:");
4122 int length = local_interfaces()->length();
4123 for (int i = 0; i < length; i++) {
4124 debug_stream.print(" " PTR_FORMAT,
4125 p2i(local_interfaces()->at(i)));
4126 }
4127 }
4128
4129 // Class loader
4130 debug_stream.print(" loader: [");
4131 loader_data->print_value_on(&debug_stream);
4132 debug_stream.print("]");
4133
4134 // Classfile checksum
4135 if (cfs) {
4136 debug_stream.print(" bytes: %d checksum: %08x",
4137 cfs->length(),
4138 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4139 cfs->length()));
4140 }
4141
4142 msg.debug("%s", debug_stream.as_string());
4143 }
4144 }
4145
4146 void InstanceKlass::print_class_load_cause_logging() const {
4147 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4148 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4149 JavaThread* current = JavaThread::current();
4150 ResourceMark rm(current);
4151 const char* name = external_name();
4152
4153 if (LogClassLoadingCauseFor == nullptr ||
4154 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4155 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4156 return;
4157 }
4158
4159 // Log Java stack first
4160 {
4161 LogMessage(class, load, cause) msg;
4162 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4163
4164 info_stream.print_cr("Java stack when loading %s:", name);
4165 current->print_stack_on(&info_stream);
4166 }
4167
4168 // Log native stack second
4169 if (log_cause_native) {
4170 // Log to string first so that lines can be indented
4171 stringStream stack_stream;
4172 char buf[O_BUFLEN];
4173 address lastpc = nullptr;
4174 NativeStackPrinter nsp(current);
4175 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4176 true /* print_source_info */, -1 /* max stack */);
4177
4178 LogMessage(class, load, cause, native) msg;
4179 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4180 info_stream.print_cr("Native stack when loading %s:", name);
4181
4182 // Print each native stack line to the log
4183 int size = (int) stack_stream.size();
4184 char* stack = stack_stream.as_string();
4185 char* stack_end = stack + size;
4186 char* line_start = stack;
4187 for (char* p = stack; p < stack_end; p++) {
4188 if (*p == '\n') {
4189 *p = '\0';
4190 info_stream.print_cr("\t%s", line_start);
4191 line_start = p + 1;
4192 }
4193 }
4194 if (line_start < stack_end) {
4195 info_stream.print_cr("\t%s", line_start);
4196 }
4197 }
4198 }
4199 }
4200
4201 // Verification
4202
4203 class VerifyFieldClosure: public BasicOopIterateClosure {
4204 protected:
4205 template <class T> void do_oop_work(T* p) {
4206 oop obj = RawAccess<>::oop_load(p);
4207 if (!oopDesc::is_oop_or_null(obj)) {
4208 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4209 Universe::print_on(tty);
4210 guarantee(false, "boom");
4211 }
4212 }
4213 public:
4214 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4215 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4216 };
4217
4218 void InstanceKlass::verify_on(outputStream* st) {
4219 #ifndef PRODUCT
4220 // Avoid redundant verifies, this really should be in product.
4221 if (_verify_count == Universe::verify_count()) return;
4222 _verify_count = Universe::verify_count();
4223 #endif
4224
4225 // Verify Klass
4226 Klass::verify_on(st);
4227
4228 // Verify that klass is present in ClassLoaderData
4229 guarantee(class_loader_data()->contains_klass(this),
4230 "this class isn't found in class loader data");
4231
4232 // Verify vtables
4233 if (is_linked()) {
4234 // $$$ This used to be done only for m/s collections. Doing it
4235 // always seemed a valid generalization. (DLD -- 6/00)
4236 vtable().verify(st);
4237 }
4238
4239 // Verify first subklass
4240 if (subklass() != nullptr) {
4241 guarantee(subklass()->is_klass(), "should be klass");
4242 }
4243
4244 // Verify siblings
4245 Klass* super = this->super();
4246 Klass* sib = next_sibling();
4247 if (sib != nullptr) {
4248 if (sib == this) {
4249 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4250 }
4251
4252 guarantee(sib->is_klass(), "should be klass");
4253 guarantee(sib->super() == super, "siblings should have same superklass");
4254 }
4255
4256 // Verify local interfaces
4257 if (local_interfaces()) {
4258 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4259 for (int j = 0; j < local_interfaces->length(); j++) {
4260 InstanceKlass* e = local_interfaces->at(j);
4261 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4262 }
4263 }
4264
4265 // Verify transitive interfaces
4266 if (transitive_interfaces() != nullptr) {
4267 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4268 for (int j = 0; j < transitive_interfaces->length(); j++) {
4269 InstanceKlass* e = transitive_interfaces->at(j);
4270 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4271 }
4272 }
4273
4274 // Verify methods
4275 if (methods() != nullptr) {
4276 Array<Method*>* methods = this->methods();
4277 for (int j = 0; j < methods->length(); j++) {
4278 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4279 }
4280 for (int j = 0; j < methods->length() - 1; j++) {
4281 Method* m1 = methods->at(j);
4282 Method* m2 = methods->at(j + 1);
4283 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4284 }
4285 }
4286
4287 // Verify method ordering
4288 if (method_ordering() != nullptr) {
4289 Array<int>* method_ordering = this->method_ordering();
4290 int length = method_ordering->length();
4291 if (JvmtiExport::can_maintain_original_method_order() ||
4292 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4293 guarantee(length == methods()->length(), "invalid method ordering length");
4294 jlong sum = 0;
4295 for (int j = 0; j < length; j++) {
4296 int original_index = method_ordering->at(j);
4297 guarantee(original_index >= 0, "invalid method ordering index");
4298 guarantee(original_index < length, "invalid method ordering index");
4299 sum += original_index;
4300 }
4301 // Verify sum of indices 0,1,...,length-1
4302 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4303 } else {
4304 guarantee(length == 0, "invalid method ordering length");
4305 }
4306 }
4307
4308 // Verify default methods
4309 if (default_methods() != nullptr) {
4310 Array<Method*>* methods = this->default_methods();
4311 for (int j = 0; j < methods->length(); j++) {
4312 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4313 }
4314 for (int j = 0; j < methods->length() - 1; j++) {
4315 Method* m1 = methods->at(j);
4316 Method* m2 = methods->at(j + 1);
4317 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4318 }
4319 }
4320
4321 // Verify JNI static field identifiers
4322 if (jni_ids() != nullptr) {
4323 jni_ids()->verify(this);
4324 }
4325
4326 // Verify other fields
4327 if (constants() != nullptr) {
4328 guarantee(constants()->is_constantPool(), "should be constant pool");
4329 }
4330 }
4331
4332 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4333 Klass::oop_verify_on(obj, st);
4334 VerifyFieldClosure blk;
4335 obj->oop_iterate(&blk);
4336 }
4337
4338 // JNIid class for jfieldIDs only
4339 // Note to reviewers:
4340 // These JNI functions are just moved over to column 1 and not changed
4341 // in the compressed oops workspace.
4342 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4343 _holder = holder;
4344 _offset = offset;
4345 _next = next;
4346 DEBUG_ONLY(_is_static_field_id = false;)
4347 }
4348
4349 JNIid* JNIid::find(int offset) {
4350 JNIid* current = this;
4351 while (current != nullptr) {
4352 if (current->offset() == offset) return current;
4353 current = current->next();
4354 }
4355 return nullptr;
4356 }
4357
4358 void JNIid::deallocate(JNIid* current) {
4359 while (current != nullptr) {
4360 JNIid* next = current->next();
4361 delete current;
4362 current = next;
4363 }
4364 }
4365
4366 void JNIid::verify(InstanceKlass* holder) {
4367 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4368 int end_field_offset;
4369 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4370
4371 JNIid* current = this;
4372 while (current != nullptr) {
4373 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4374 #ifdef ASSERT
4375 int o = current->offset();
4376 if (current->is_static_field_id()) {
4377 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4378 }
4379 #endif
4380 current = current->next();
4381 }
4382 }
4383
4384 void InstanceKlass::set_init_state(ClassState state) {
4385 #ifdef ASSERT
4386 bool good_state = in_aot_cache() ? (_init_state <= state)
4387 : (_init_state < state);
4388 assert(good_state || state == allocated, "illegal state transition");
4389 #endif
4390 assert(_init_thread == nullptr, "should be cleared before state change");
4391 AtomicAccess::release_store(&_init_state, state);
4392 }
4393
4394 #if INCLUDE_JVMTI
4395
4396 // RedefineClasses() support for previous versions
4397
4398 // Globally, there is at least one previous version of a class to walk
4399 // during class unloading, which is saved because old methods in the class
4400 // are still running. Otherwise the previous version list is cleaned up.
4401 bool InstanceKlass::_should_clean_previous_versions = false;
4402
4403 // Returns true if there are previous versions of a class for class
4404 // unloading only. Also resets the flag to false. purge_previous_version
4405 // will set the flag to true if there are any left, i.e., if there's any
4406 // work to do for next time. This is to avoid the expensive code cache
4407 // walk in CLDG::clean_deallocate_lists().
4408 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4409 bool ret = _should_clean_previous_versions;
4410 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4411 ret ? "true" : "false");
4412 _should_clean_previous_versions = false;
4413 return ret;
4414 }
4415
4416 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4417 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4418 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4419 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4420 Array<Method*>* method_refs = klass->methods();
4421 for (int k = 0; k < method_refs->length(); k++) {
4422 Method* method = method_refs->at(k);
4423 // Only need to clear obsolete methods.
4424 if (method != nullptr && method->is_obsolete()) {
4425 method->clear_jmethod_id();
4426 }
4427 }
4428 }
4429
4430 // Purge previous versions before adding new previous versions of the class and
4431 // during class unloading.
4432 void InstanceKlass::purge_previous_version_list() {
4433 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4434 assert(has_been_redefined(), "Should only be called for main class");
4435
4436 // Quick exit.
4437 if (previous_versions() == nullptr) {
4438 return;
4439 }
4440
4441 // This klass has previous versions so see what we can cleanup
4442 // while it is safe to do so.
4443
4444 int deleted_count = 0; // leave debugging breadcrumbs
4445 int live_count = 0;
4446 ClassLoaderData* loader_data = class_loader_data();
4447 assert(loader_data != nullptr, "should never be null");
4448
4449 ResourceMark rm;
4450 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4451
4452 // previous versions are linked together through the InstanceKlass
4453 InstanceKlass* pv_node = previous_versions();
4454 InstanceKlass* last = this;
4455 int version = 0;
4456
4457 // check the previous versions list
4458 for (; pv_node != nullptr; ) {
4459
4460 ConstantPool* pvcp = pv_node->constants();
4461 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4462
4463 if (!pvcp->on_stack()) {
4464 // If the constant pool isn't on stack, none of the methods
4465 // are executing. Unlink this previous_version.
4466 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4467 // so will be deallocated during the next phase of class unloading.
4468 log_trace(redefine, class, iklass, purge)
4469 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4470 // Unlink from previous version list.
4471 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4472 InstanceKlass* next = pv_node->previous_versions();
4473 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4474 pv_node->link_previous_versions(nullptr); // point next to null
4475 last->link_previous_versions(next);
4476 // Delete this node directly. Nothing is referring to it and we don't
4477 // want it to increase the counter for metadata to delete in CLDG.
4478 MetadataFactory::free_metadata(loader_data, pv_node);
4479 pv_node = next;
4480 deleted_count++;
4481 version++;
4482 continue;
4483 } else {
4484 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4485 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4486 live_count++;
4487 if (pvcp->in_aot_cache()) {
4488 // Shared previous versions can never be removed so no cleaning is needed.
4489 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4490 } else {
4491 // Previous version alive, set that clean is needed for next time.
4492 _should_clean_previous_versions = true;
4493 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4494 }
4495 }
4496
4497 // next previous version
4498 last = pv_node;
4499 pv_node = pv_node->previous_versions();
4500 version++;
4501 }
4502 log_trace(redefine, class, iklass, purge)
4503 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4504 }
4505
4506 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4507 int emcp_method_count) {
4508 int obsolete_method_count = old_methods->length() - emcp_method_count;
4509
4510 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4511 _previous_versions != nullptr) {
4512 // We have a mix of obsolete and EMCP methods so we have to
4513 // clear out any matching EMCP method entries the hard way.
4514 int local_count = 0;
4515 for (int i = 0; i < old_methods->length(); i++) {
4516 Method* old_method = old_methods->at(i);
4517 if (old_method->is_obsolete()) {
4518 // only obsolete methods are interesting
4519 Symbol* m_name = old_method->name();
4520 Symbol* m_signature = old_method->signature();
4521
4522 // previous versions are linked together through the InstanceKlass
4523 int j = 0;
4524 for (InstanceKlass* prev_version = _previous_versions;
4525 prev_version != nullptr;
4526 prev_version = prev_version->previous_versions(), j++) {
4527
4528 Array<Method*>* method_refs = prev_version->methods();
4529 for (int k = 0; k < method_refs->length(); k++) {
4530 Method* method = method_refs->at(k);
4531
4532 if (!method->is_obsolete() &&
4533 method->name() == m_name &&
4534 method->signature() == m_signature) {
4535 // The current RedefineClasses() call has made all EMCP
4536 // versions of this method obsolete so mark it as obsolete
4537 log_trace(redefine, class, iklass, add)
4538 ("%s(%s): flush obsolete method @%d in version @%d",
4539 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4540
4541 method->set_is_obsolete();
4542 break;
4543 }
4544 }
4545
4546 // The previous loop may not find a matching EMCP method, but
4547 // that doesn't mean that we can optimize and not go any
4548 // further back in the PreviousVersion generations. The EMCP
4549 // method for this generation could have already been made obsolete,
4550 // but there still may be an older EMCP method that has not
4551 // been made obsolete.
4552 }
4553
4554 if (++local_count >= obsolete_method_count) {
4555 // no more obsolete methods so bail out now
4556 break;
4557 }
4558 }
4559 }
4560 }
4561 }
4562
4563 // Save the scratch_class as the previous version if any of the methods are running.
4564 // The previous_versions are used to set breakpoints in EMCP methods and they are
4565 // also used to clean MethodData links to redefined methods that are no longer running.
4566 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4567 int emcp_method_count) {
4568 assert(Thread::current()->is_VM_thread(),
4569 "only VMThread can add previous versions");
4570
4571 ResourceMark rm;
4572 log_trace(redefine, class, iklass, add)
4573 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4574
4575 // Clean out old previous versions for this class
4576 purge_previous_version_list();
4577
4578 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4579 // a previous redefinition may be made obsolete by this redefinition.
4580 Array<Method*>* old_methods = scratch_class->methods();
4581 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4582
4583 // If the constant pool for this previous version of the class
4584 // is not marked as being on the stack, then none of the methods
4585 // in this previous version of the class are on the stack so
4586 // we don't need to add this as a previous version.
4587 ConstantPool* cp_ref = scratch_class->constants();
4588 if (!cp_ref->on_stack()) {
4589 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4590 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4591 return;
4592 }
4593
4594 // Add previous version if any methods are still running or if this is
4595 // a shared class which should never be removed.
4596 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4597 scratch_class->link_previous_versions(previous_versions());
4598 link_previous_versions(scratch_class);
4599 if (cp_ref->in_aot_cache()) {
4600 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4601 } else {
4602 // We only set clean_previous_versions flag for processing during class
4603 // unloading for non-shared classes.
4604 _should_clean_previous_versions = true;
4605 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4606 }
4607 } // end add_previous_version()
4608
4609 #endif // INCLUDE_JVMTI
4610
4611 Method* InstanceKlass::method_with_idnum(int idnum) const {
4612 Method* m = nullptr;
4613 if (idnum < methods()->length()) {
4614 m = methods()->at(idnum);
4615 }
4616 if (m == nullptr || m->method_idnum() != idnum) {
4617 for (int index = 0; index < methods()->length(); ++index) {
4618 m = methods()->at(index);
4619 if (m->method_idnum() == idnum) {
4620 return m;
4621 }
4622 }
4623 // None found, return null for the caller to handle.
4624 return nullptr;
4625 }
4626 return m;
4627 }
4628
4629
4630 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4631 if (idnum >= methods()->length()) {
4632 return nullptr;
4633 }
4634 Method* m = methods()->at(idnum);
4635 if (m != nullptr && m->orig_method_idnum() == idnum) {
4636 return m;
4637 }
4638 // Obsolete method idnum does not match the original idnum
4639 for (int index = 0; index < methods()->length(); ++index) {
4640 m = methods()->at(index);
4641 if (m->orig_method_idnum() == idnum) {
4642 return m;
4643 }
4644 }
4645 // None found, return null for the caller to handle.
4646 return nullptr;
4647 }
4648
4649
4650 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4651 const InstanceKlass* holder = get_klass_version(version);
4652 if (holder == nullptr) {
4653 return nullptr; // The version of klass is gone, no method is found
4654 }
4655 return holder->method_with_orig_idnum(idnum);
4656 }
4657
4658 #if INCLUDE_JVMTI
4659 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4660 return _cached_class_file;
4661 }
4662
4663 jint InstanceKlass::get_cached_class_file_len() {
4664 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4665 }
4666
4667 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4668 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4669 }
4670 #endif
4671
4672 // Make a step iterating over the class hierarchy under the root class.
4673 // Skips subclasses if requested.
4674 void ClassHierarchyIterator::next() {
4675 assert(_current != nullptr, "required");
4676 if (_visit_subclasses && _current->subklass() != nullptr) {
4677 _current = _current->subklass();
4678 return; // visit next subclass
4679 }
4680 _visit_subclasses = true; // reset
4681 while (_current->next_sibling() == nullptr && _current != _root) {
4682 _current = _current->java_super(); // backtrack; no more sibling subclasses left
4683 }
4684 if (_current == _root) {
4685 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4686 _current = nullptr;
4687 return;
4688 }
4689 _current = _current->next_sibling();
4690 return; // visit next sibling subclass
4691 }