1 /*
2 * Copyright (c) 1997, 2026, 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/aotHeap.hpp"
27 #include "cds/aotLinkedClassBulkLoader.hpp"
28 #include "cds/aotMetaspace.hpp"
29 #include "cds/archiveUtils.hpp"
30 #include "cds/cdsConfig.hpp"
31 #include "cds/cdsEnumKlass.hpp"
32 #include "cds/classListWriter.hpp"
33 #include "classfile/classFileParser.hpp"
34 #include "classfile/classFileStream.hpp"
35 #include "classfile/classLoader.hpp"
36 #include "classfile/classLoaderData.inline.hpp"
37 #include "classfile/javaClasses.hpp"
38 #include "classfile/javaStackTraceClasses.hpp"
39 #include "classfile/moduleEntry.hpp"
40 #include "classfile/systemDictionary.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/verifier.hpp"
43 #include "classfile/vmClasses.hpp"
44 #include "classfile/vmSymbols.hpp"
45 #include "code/codeCache.hpp"
46 #include "code/dependencyContext.hpp"
47 #include "compiler/compilationPolicy.hpp"
48 #include "compiler/compileBroker.hpp"
49 #include "gc/shared/collectedHeap.inline.hpp"
50 #include "interpreter/bytecodeStream.hpp"
51 #include "interpreter/oopMapCache.hpp"
52 #include "interpreter/rewriter.hpp"
53 #include "jvm.h"
54 #include "jvmtifiles/jvmti.h"
55 #include "klass.inline.hpp"
56 #include "logging/log.hpp"
57 #include "logging/logMessage.hpp"
58 #include "logging/logStream.hpp"
59 #include "memory/allocation.inline.hpp"
60 #include "memory/iterator.inline.hpp"
61 #include "memory/metadataFactory.hpp"
62 #include "memory/metaspaceClosure.hpp"
63 #include "memory/oopFactory.hpp"
64 #include "memory/resourceArea.hpp"
65 #include "memory/universe.hpp"
66 #include "oops/constantPool.hpp"
67 #include "oops/fieldStreams.inline.hpp"
68 #include "oops/instanceClassLoaderKlass.hpp"
69 #include "oops/instanceKlass.inline.hpp"
70 #include "oops/instanceMirrorKlass.hpp"
71 #include "oops/instanceOop.hpp"
72 #include "oops/instanceStackChunkKlass.hpp"
73 #include "oops/klass.inline.hpp"
74 #include "oops/layoutKind.hpp"
75 #include "oops/markWord.hpp"
76 #include "oops/method.hpp"
77 #include "oops/oop.inline.hpp"
78 #include "oops/recordComponent.hpp"
79 #include "oops/refArrayKlass.hpp"
80 #include "oops/symbol.hpp"
81 #include "oops/valueKlass.hpp"
82 #include "prims/jvmtiExport.hpp"
83 #include "prims/jvmtiRedefineClasses.hpp"
84 #include "prims/jvmtiThreadState.hpp"
85 #include "prims/methodComparator.hpp"
86 #include "runtime/arguments.hpp"
87 #include "runtime/atomicAccess.hpp"
88 #include "runtime/deoptimization.hpp"
89 #include "runtime/fieldDescriptor.inline.hpp"
90 #include "runtime/handles.inline.hpp"
91 #include "runtime/javaCalls.hpp"
92 #include "runtime/javaThread.inline.hpp"
93 #include "runtime/mutexLocker.hpp"
94 #include "runtime/orderAccess.hpp"
95 #include "runtime/os.inline.hpp"
96 #include "runtime/reflection.hpp"
97 #include "runtime/synchronizer.hpp"
98 #include "runtime/threads.hpp"
99 #include "services/classLoadingService.hpp"
100 #include "services/finalizerService.hpp"
101 #include "services/threadService.hpp"
102 #include "utilities/dtrace.hpp"
103 #include "utilities/events.hpp"
104 #include "utilities/macros.hpp"
105 #include "utilities/nativeStackPrinter.hpp"
106 #include "utilities/ostream.hpp"
107 #include "utilities/stringUtils.hpp"
108 #ifdef COMPILER1
109 #include "c1/c1_Compiler.hpp"
110 #endif
111 #if INCLUDE_JFR
112 #include "jfr/jfrEvents.hpp"
113 #endif
114
115 #ifdef DTRACE_ENABLED
116
117
118 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
119 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
120 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
121 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
122 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
123 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
124 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
125 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
126 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
127 { \
128 char* data = nullptr; \
129 int len = 0; \
130 Symbol* clss_name = name(); \
131 if (clss_name != nullptr) { \
132 data = (char*)clss_name->bytes(); \
133 len = clss_name->utf8_length(); \
134 } \
135 HOTSPOT_CLASS_INITIALIZATION_##type( \
136 data, len, (void*)class_loader(), thread_type); \
137 }
138
139 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
140 { \
141 char* data = nullptr; \
142 int len = 0; \
143 Symbol* clss_name = name(); \
144 if (clss_name != nullptr) { \
145 data = (char*)clss_name->bytes(); \
146 len = clss_name->utf8_length(); \
147 } \
148 HOTSPOT_CLASS_INITIALIZATION_##type( \
149 data, len, (void*)class_loader(), thread_type, wait); \
150 }
151
152 #else // ndef DTRACE_ENABLED
153
154 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
155 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
156
157 #endif // ndef DTRACE_ENABLED
158
159 void ValueFieldInfo::metaspace_pointers_do(MetaspaceClosure* it) {
160 log_trace(cds)("Iter(ValueFieldInfo): %p", this);
161 it->push(&_klass);
162 }
163
164 void ValueFieldInfo::print() const {
165 print_on(tty);
166 }
167
168 void ValueFieldInfo::print_on(outputStream* st) const {
169 st->print_cr("_klass: " PTR_FORMAT, p2i(_klass));
170 if (_klass != nullptr) {
171 StreamIndentor si(st);
172 _klass->print_on(st);
173 st->cr();
174 }
175
176 st->print("_layout: ");
177 LayoutKindHelper::print_on(_kind, st);
178 }
179
180 // A value class is considered naturally atomic if its layout,
181 // once all fields flattening have been applied, contains a single primitive
182 // or oop field. Because primitive types and oops are already handled
183 // atomically by the JVM, it means that there's no need to take
184 // special precautions when reading or writing this value to guarantee
185 // cross-fields invariants. Nullability has to be taken into consideration,
186 // as the null-marker has to be considered as a pseudo-field which must
187 // be kept consistent with the payload. The only kind of value class
188 // that can be considered naturally atomic when nullable is the empty
189 // value classes because the dummy field is re-used as a null-marker.
190 bool InstanceKlass::is_naturally_atomic(bool null_free) const {
191 assert(!is_identity_class(), "Doesn't make sense for an identity class");
192 if (null_free) {
193 // No extra null-marker, just check the layout of the fields
194 return _misc_flags.is_naturally_atomic();
195 } else {
196 // Requires a null-marker, can't have any other fields
197 return ValueKlass::cast(this)->is_empty_value_type();
198 }
199 }
200
201 bool InstanceKlass::_finalization_enabled = true;
202 static int call_class_initializer_counter = 0; // for debugging
203
204 static inline bool is_class_loader(const Symbol* class_name,
205 const ClassFileParser& parser) {
206 assert(class_name != nullptr, "invariant");
207
208 if (class_name == vmSymbols::java_lang_ClassLoader()) {
209 return true;
210 }
211
212 if (vmClasses::ClassLoader_klass_is_loaded()) {
213 const Klass* const super_klass = parser.super_klass();
214 if (super_klass != nullptr) {
215 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
216 return true;
217 }
218 }
219 }
220 return false;
221 }
222
223 bool InstanceKlass::field_is_null_free_value_type(int index) const {
224 return field(index).field_flags().is_null_free_value_type();
225 }
226
227 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
228 if (_loadable_descriptors == nullptr) return false;
229 for (int i = 0; i < _loadable_descriptors->length(); i++) {
230 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
231 if (class_name == name) return true;
232 }
233 return false;
234 }
235
236 int InstanceKlass::field_null_marker_offset(int index) const {
237 const FieldInfo field = this->field(index);
238 if (!field.field_flags().has_null_marker()) {
239 return -1;
240 }
241
242 const ValueKlass* const vk = value_field_info(index).klass();
243 const int nm_offset = vk->null_marker_offset_in_payload();
244 return field_offset(index) + nm_offset;
245 }
246
247 static inline bool is_stack_chunk_class(const Symbol* class_name,
248 const ClassLoaderData* loader_data) {
249 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
250 loader_data->is_the_null_class_loader_data());
251 }
252
253 // private: called to verify that k is a static member of this nest.
254 // We know that k is an instance class in the same package and hence the
255 // same classloader.
256 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
257 assert(!is_hidden(), "unexpected hidden class");
258 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
259 if (log_is_enabled(Trace, class, nestmates)) {
260 ResourceMark rm(current);
261 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
262 k->external_name(), this->external_name());
263 }
264 return false;
265 }
266
267 if (log_is_enabled(Trace, class, nestmates)) {
268 ResourceMark rm(current);
269 log_trace(class, nestmates)("Checking nest membership of %s in %s",
270 k->external_name(), this->external_name());
271 }
272
273 // Check for the named class in _nest_members.
274 // We don't resolve, or load, any classes.
275 for (int i = 0; i < _nest_members->length(); i++) {
276 int cp_index = _nest_members->at(i);
277 Symbol* name = _constants->klass_name_at(cp_index);
278 if (name == k->name()) {
279 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
280 return true;
281 }
282 }
283 log_trace(class, nestmates)("- class is NOT a nest member!");
284 return false;
285 }
286
287 // Called to verify that k is a permitted subclass of this class.
288 // The incoming stringStream is used to format the messages for error logging and for the caller
289 // to use for exception throwing.
290 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
291 Thread* current = Thread::current();
292 assert(k != nullptr, "sanity check");
293 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
294 "unexpected empty _permitted_subclasses array");
295
296 if (log_is_enabled(Trace, class, sealed)) {
297 ResourceMark rm(current);
298 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
299 k->external_name(), this->external_name());
300 }
301
302 // Check that the class and its super are in the same module.
303 if (k->module() != this->module()) {
304 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
305 "and sealed class %s is in module '%s' with loader %s",
306 k->external_name(),
307 k->module()->name_as_C_string(),
308 k->module()->loader_data()->loader_name_and_id(),
309 this->external_name(),
310 this->module()->name_as_C_string(),
311 this->module()->loader_data()->loader_name_and_id());
312 log_trace(class, sealed)(" - %s", ss.as_string());
313 return false;
314 }
315
316 if (!k->is_public() && !is_same_class_package(k)) {
317 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
318 "and sealed class %s is in package '%s' with classloader %s",
319 k->external_name(),
320 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
321 k->module()->loader_data()->loader_name_and_id(),
322 this->external_name(),
323 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
324 this->module()->loader_data()->loader_name_and_id());
325 log_trace(class, sealed)(" - %s", ss.as_string());
326 return false;
327 }
328
329 for (int i = 0; i < _permitted_subclasses->length(); i++) {
330 int cp_index = _permitted_subclasses->at(i);
331 Symbol* name = _constants->klass_name_at(cp_index);
332 if (name == k->name()) {
333 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
334 return true;
335 }
336 }
337
338 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
339 k->external_name(), this->external_name());
340 log_trace(class, sealed)(" - %s", ss.as_string());
341 return false;
342 }
343
344 // Return nest-host class, resolving, validating and saving it if needed.
345 // In cases where this is called from a thread that cannot do classloading
346 // (such as a native JIT thread) then we simply return null, which in turn
347 // causes the access check to return false. Such code will retry the access
348 // from a more suitable environment later. Otherwise the _nest_host is always
349 // set once this method returns.
350 // Any errors from nest-host resolution must be preserved so they can be queried
351 // from higher-level access checking code, and reported as part of access checking
352 // exceptions.
353 // VirtualMachineErrors are propagated with a null return.
354 // Under any conditions where the _nest_host can be set to non-null the resulting
355 // value of it and, if applicable, the nest host resolution/validation error,
356 // are idempotent.
357 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
358 InstanceKlass* nest_host_k = _nest_host;
359 if (nest_host_k != nullptr) {
360 return nest_host_k;
361 }
362
363 ResourceMark rm(THREAD);
364
365 // need to resolve and save our nest-host class.
366 if (_nest_host_index != 0) { // we have a real nest_host
367 // Before trying to resolve check if we're in a suitable context
368 bool can_resolve = THREAD->can_call_java();
369 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
370 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
371 this->external_name());
372 return nullptr; // sentinel to say "try again from a different context"
373 }
374
375 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
376 this->external_name(),
377 _constants->klass_name_at(_nest_host_index)->as_C_string());
378
379 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
380 if (HAS_PENDING_EXCEPTION) {
381 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
382 return nullptr; // propagate VMEs
383 }
384 stringStream ss;
385 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
386 ss.print("Nest host resolution of %s with host %s failed: ",
387 this->external_name(), target_host_class);
388 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
389 constantPoolHandle cph(THREAD, constants());
390 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
391 CLEAR_PENDING_EXCEPTION;
392
393 log_trace(class, nestmates)("%s", ss.base());
394 } else {
395 // A valid nest-host is an instance class in the current package that lists this
396 // class as a nest member. If any of these conditions are not met the class is
397 // its own nest-host.
398 const char* error = nullptr;
399
400 // JVMS 5.4.4 indicates package check comes first
401 if (is_same_class_package(k)) {
402 // Now check actual membership. We can't be a member if our "host" is
403 // not an instance class.
404 if (k->is_instance_klass()) {
405 nest_host_k = InstanceKlass::cast(k);
406 bool is_member = nest_host_k->has_nest_member(THREAD, this);
407 if (is_member) {
408 _nest_host = nest_host_k; // save resolved nest-host value
409
410 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
411 this->external_name(), k->external_name());
412 return nest_host_k;
413 } else {
414 error = "current type is not listed as a nest member";
415 }
416 } else {
417 error = "host is not an instance class";
418 }
419 } else {
420 error = "types are in different packages";
421 }
422
423 // something went wrong, so record what and log it
424 {
425 stringStream ss;
426 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
427 this->external_name(),
428 this->class_loader_data()->loader_name_and_id(),
429 k->external_name(),
430 k->class_loader_data()->loader_name_and_id(),
431 error);
432 constantPoolHandle cph(THREAD, constants());
433 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
434 log_trace(class, nestmates)("%s", ss.base());
435 }
436 }
437 } else {
438 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
439 this->external_name());
440 }
441
442 // Either not in an explicit nest, or else an error occurred, so
443 // the nest-host is set to `this`. Any thread that sees this assignment
444 // will also see any setting of nest_host_error(), if applicable.
445 return (_nest_host = this);
446 }
447
448 // Dynamic nest member support: set this class's nest host to the given class.
449 // This occurs as part of the class definition, as soon as the instanceKlass
450 // has been created and doesn't require further resolution. The code:
451 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
452 // results in:
453 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
454 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
455 // We also know the "host" is a valid nest-host in the same package so we can
456 // assert some of those facts.
457 void InstanceKlass::set_nest_host(InstanceKlass* host) {
458 assert(is_hidden(), "must be a hidden class");
459 assert(host != nullptr, "null nest host specified");
460 assert(_nest_host == nullptr, "current class has resolved nest-host");
461 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
462 nest_host_error());
463 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
464 (host->_nest_host == host), "proposed host is not a valid nest-host");
465 // Can't assert this as package is not set yet:
466 // assert(is_same_class_package(host), "proposed host is in wrong package");
467
468 if (log_is_enabled(Trace, class, nestmates)) {
469 ResourceMark rm;
470 const char* msg = "";
471 // a hidden class does not expect a statically defined nest-host
472 if (_nest_host_index > 0) {
473 msg = "(the NestHost attribute in the current class is ignored)";
474 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
475 msg = "(the NestMembers attribute in the current class is ignored)";
476 }
477 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
478 this->external_name(),
479 host->external_name(),
480 msg);
481 }
482 // set dynamic nest host
483 _nest_host = host;
484 // Record dependency to keep nest host from being unloaded before this class.
485 ClassLoaderData* this_key = class_loader_data();
486 assert(this_key != nullptr, "sanity");
487 this_key->record_dependency(host);
488 }
489
490 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
491 // or we are k's nest_host - all of which is covered by comparing the two
492 // resolved_nest_hosts.
493 // Any exceptions (i.e. VMEs) are propagated.
494 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
495
496 assert(this != k, "this should be handled by higher-level code");
497
498 // Per JVMS 5.4.4 we first resolve and validate the current class, then
499 // the target class k.
500
501 InstanceKlass* cur_host = nest_host(CHECK_false);
502 if (cur_host == nullptr) {
503 return false;
504 }
505
506 Klass* k_nest_host = k->nest_host(CHECK_false);
507 if (k_nest_host == nullptr) {
508 return false;
509 }
510
511 bool access = (cur_host == k_nest_host);
512
513 ResourceMark rm(THREAD);
514 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
515 this->external_name(),
516 access ? "" : "NOT ",
517 k->external_name());
518 return access;
519 }
520
521 const char* InstanceKlass::nest_host_error() {
522 if (_nest_host_index == 0) {
523 return nullptr;
524 } else {
525 constantPoolHandle cph(Thread::current(), constants());
526 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
527 }
528 }
529
530 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
531 const int size = InstanceKlass::size(parser.vtable_size(),
532 parser.itable_size(),
533 nonstatic_oop_map_size(parser.total_oop_map_count()),
534 parser.is_interface(),
535 parser.is_concrete_value_class());
536
537 const Symbol* const class_name = parser.class_name();
538 assert(class_name != nullptr, "invariant");
539 ClassLoaderData* loader_data = parser.loader_data();
540 assert(loader_data != nullptr, "invariant");
541
542 InstanceKlass* ik;
543
544 // Allocation
545 if (parser.is_instance_ref_klass()) {
546 // java.lang.ref.Reference
547 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
548 } else if (class_name == vmSymbols::java_lang_Class()) {
549 // mirror - java.lang.Class
550 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
551 } else if (is_stack_chunk_class(class_name, loader_data)) {
552 // stack chunk
553 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
554 } else if (is_class_loader(class_name, parser)) {
555 // class loader - java.lang.ClassLoader
556 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
557 } else if (parser.is_concrete_value_class()) {
558 // value type
559 ik = new (loader_data, size, THREAD) ValueKlass(parser);
560 } else {
561 // normal
562 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
563 }
564
565 assert(ik == nullptr || CompressedKlassPointers::is_encodable(ik),
566 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
567
568 // Check for pending exception before adding to the loader data and incrementing
569 // class count. Can get OOM here.
570 if (HAS_PENDING_EXCEPTION) {
571 return nullptr;
572 }
573
574 return ik;
575 }
576
577 // copy method ordering from resource area to Metaspace
578 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
579 if (m != nullptr) {
580 // allocate a new array and copy contents (memcpy?)
581 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
582 for (int i = 0; i < m->length(); i++) {
583 _method_ordering->at_put(i, m->at(i));
584 }
585 } else {
586 _method_ordering = Universe::the_empty_int_array();
587 }
588 }
589
590 // create a new array of vtable_indices for default methods
591 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
592 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
593 assert(default_vtable_indices() == nullptr, "only create once");
594 set_default_vtable_indices(vtable_indices);
595 return vtable_indices;
596 }
597
598
599 InstanceKlass::InstanceKlass() {
600 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
601 }
602
603 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, markWord prototype_header, ReferenceType reference_type) :
604 Klass(kind, prototype_header),
605 _nest_members(nullptr),
606 _nest_host(nullptr),
607 _permitted_subclasses(nullptr),
608 _record_components(nullptr),
609 _static_field_size(parser.static_field_size()),
610 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
611 _itable_len(parser.itable_size()),
612 _nest_host_index(0),
613 _init_state(allocated),
614 _reference_type(reference_type),
615 _acmp_maps_offset(0),
616 _init_thread(nullptr),
617 _value_field_info_array(nullptr),
618 _loadable_descriptors(nullptr),
619 _acmp_maps_array(nullptr),
620 _adr_value_klass_members(nullptr)
621 {
622 set_vtable_length(parser.vtable_size());
623 set_access_flags(parser.access_flags());
624 if (parser.is_hidden()) set_is_hidden();
625 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
626 false));
627 if (parser.has_flat_fields()) {
628 set_has_flat_fields();
629 }
630
631 assert(nullptr == _methods, "underlying memory not zeroed?");
632 assert(is_instance_klass(), "is layout incorrect?");
633 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
634 }
635
636 void InstanceKlass::set_is_cloneable() {
637 if (name() == vmSymbols::java_lang_invoke_MemberName()) {
638 assert(is_final(), "no subclasses allowed");
639 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
640 } else if (reference_type() != REF_NONE) {
641 // Reference cloning should not be intrinsified and always happen in JVM_Clone.
642 } else {
643 set_is_cloneable_fast();
644 }
645 }
646
647 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
648 Array<Method*>* methods) {
649 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
650 !methods->in_aot_cache()) {
651 for (int i = 0; i < methods->length(); i++) {
652 Method* method = methods->at(i);
653 if (method == nullptr) continue; // maybe null if error processing
654 // Only want to delete methods that are not executing for RedefineClasses.
655 // The previous version will point to them so they're not totally dangling
656 assert (!method->on_stack(), "shouldn't be called with methods on stack");
657 MetadataFactory::free_metadata(loader_data, method);
658 }
659 MetadataFactory::free_array<Method*>(loader_data, methods);
660 }
661 }
662
663 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
664 const InstanceKlass* super_klass,
665 Array<InstanceKlass*>* local_interfaces,
666 Array<InstanceKlass*>* transitive_interfaces) {
667 // Only deallocate transitive interfaces if not empty, same as super class
668 // or same as local interfaces. See code in parseClassFile.
669 Array<InstanceKlass*>* ti = transitive_interfaces;
670 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
671 // check that the interfaces don't come from super class
672 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
673 super_klass->transitive_interfaces();
674 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
675 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
676 }
677 }
678
679 // local interfaces can be empty
680 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
681 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
682 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
683 }
684 }
685
686 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
687 Array<RecordComponent*>* record_components) {
688 if (record_components != nullptr && !record_components->in_aot_cache()) {
689 for (int i = 0; i < record_components->length(); i++) {
690 RecordComponent* record_component = record_components->at(i);
691 MetadataFactory::free_metadata(loader_data, record_component);
692 }
693 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
694 }
695 }
696
697 // This function deallocates the metadata and C heap pointers that the
698 // InstanceKlass points to.
699 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
700 // Orphan the mirror first, CMS thinks it's still live.
701 if (java_mirror() != nullptr) {
702 java_lang_Class::set_klass(java_mirror(), nullptr);
703 }
704
705 // Also remove mirror from handles
706 loader_data->remove_handle(_java_mirror);
707
708 // Need to take this class off the class loader data list.
709 loader_data->remove_class(this);
710
711 // The array_klass for this class is created later, after error handling.
712 // For class redefinition, we keep the original class so this scratch class
713 // doesn't have an array class. Either way, assert that there is nothing
714 // to deallocate.
715 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
716
717 // Release C heap allocated data that this points to, which includes
718 // reference counting symbol names.
719 // Can't release the constant pool or MethodData C heap data here because the constant
720 // pool can be deallocated separately from the InstanceKlass for default methods and
721 // redefine classes. MethodData can also be released separately.
722 release_C_heap_structures(/* release_sub_metadata */ false);
723
724 deallocate_methods(loader_data, methods());
725 set_methods(nullptr);
726
727 deallocate_record_components(loader_data, record_components());
728 set_record_components(nullptr);
729
730 if (method_ordering() != nullptr &&
731 method_ordering() != Universe::the_empty_int_array() &&
732 !method_ordering()->in_aot_cache()) {
733 MetadataFactory::free_array<int>(loader_data, method_ordering());
734 }
735 set_method_ordering(nullptr);
736
737 // default methods can be empty
738 if (default_methods() != nullptr &&
739 default_methods() != Universe::the_empty_method_array() &&
740 !default_methods()->in_aot_cache()) {
741 MetadataFactory::free_array<Method*>(loader_data, default_methods());
742 }
743 // Do NOT deallocate the default methods, they are owned by superinterfaces.
744 set_default_methods(nullptr);
745
746 // default methods vtable indices can be empty
747 if (default_vtable_indices() != nullptr &&
748 !default_vtable_indices()->in_aot_cache()) {
749 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
750 }
751 set_default_vtable_indices(nullptr);
752
753
754 // This array is in Klass, but remove it with the InstanceKlass since
755 // this place would be the only caller and it can share memory with transitive
756 // interfaces.
757 if (secondary_supers() != nullptr &&
758 secondary_supers() != Universe::the_empty_klass_array() &&
759 // see comments in compute_secondary_supers about the following cast
760 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
761 !secondary_supers()->in_aot_cache()) {
762 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
763 }
764 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
765
766 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
767 set_transitive_interfaces(nullptr);
768 set_local_interfaces(nullptr);
769
770 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
771 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
772 }
773 set_fieldinfo_stream(nullptr);
774
775 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
776 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
777 }
778 set_fieldinfo_search_table(nullptr);
779
780 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
781 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
782 }
783 set_fields_status(nullptr);
784
785 if (value_field_info_array() != nullptr) {
786 MetadataFactory::free_array<ValueFieldInfo>(loader_data, value_field_info_array());
787 }
788 set_value_field_info_array(nullptr);
789
790 // If a method from a redefined class is using this constant pool, don't
791 // delete it, yet. The new class's previous version will point to this.
792 if (constants() != nullptr) {
793 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
794 if (!constants()->in_aot_cache()) {
795 AOTHeap::remove_scratch_resolved_references(constants());
796 MetadataFactory::free_metadata(loader_data, constants());
797 }
798 // Delete any cached resolution errors for the constant pool
799 SystemDictionary::delete_resolution_error(constants());
800
801 set_constants(nullptr);
802 }
803
804 if (inner_classes() != nullptr &&
805 inner_classes() != Universe::the_empty_short_array() &&
806 !inner_classes()->in_aot_cache()) {
807 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
808 }
809 set_inner_classes(nullptr);
810
811 if (nest_members() != nullptr &&
812 nest_members() != Universe::the_empty_short_array() &&
813 !nest_members()->in_aot_cache()) {
814 MetadataFactory::free_array<jushort>(loader_data, nest_members());
815 }
816 set_nest_members(nullptr);
817
818 if (permitted_subclasses() != nullptr &&
819 permitted_subclasses() != Universe::the_empty_short_array() &&
820 !permitted_subclasses()->in_aot_cache()) {
821 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
822 }
823 set_permitted_subclasses(nullptr);
824
825 if (loadable_descriptors() != nullptr &&
826 loadable_descriptors() != Universe::the_empty_short_array() &&
827 !loadable_descriptors()->in_aot_cache()) {
828 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
829 }
830 set_loadable_descriptors(nullptr);
831
832 if (acmp_maps_array() != nullptr) {
833 MetadataFactory::free_array<int>(loader_data, acmp_maps_array());
834 }
835 set_acmp_maps_array(nullptr);
836
837 // We should deallocate the Annotations instance if it's not in shared spaces.
838 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
839 MetadataFactory::free_metadata(loader_data, annotations());
840 }
841 set_annotations(nullptr);
842
843 SystemDictionaryShared::handle_class_unloading(this);
844
845 #if INCLUDE_CDS_JAVA_HEAP
846 if (CDSConfig::is_dumping_heap()) {
847 AOTHeap::remove_scratch_objects(this);
848 }
849 #endif
850 }
851
852 bool InstanceKlass::is_record() const {
853 return _record_components != nullptr &&
854 is_final() &&
855 super() == vmClasses::Record_klass();
856 }
857
858 bool InstanceKlass::is_sealed() const {
859 return _permitted_subclasses != nullptr &&
860 _permitted_subclasses != Universe::the_empty_short_array();
861 }
862
863 // JLS 8.9: An enum class is either implicitly final and derives
864 // from java.lang.Enum, or else is implicitly sealed to its
865 // anonymous subclasses. This query detects both kinds.
866 // It does not validate the finality or
867 // sealing conditions: it merely checks for a super of Enum.
868 // This is sufficient for recognizing well-formed enums.
869 bool InstanceKlass::is_enum_subclass() const {
870 InstanceKlass* s = super();
871 return (s == vmClasses::Enum_klass() ||
872 (s != nullptr && s->super() == vmClasses::Enum_klass()));
873 }
874
875 bool InstanceKlass::should_be_initialized() const {
876 return !is_initialized();
877 }
878
879 // Static size helper
880 int InstanceKlass::size(int vtable_length,
881 int itable_length,
882 int nonstatic_oop_map_size,
883 bool is_interface,
884 bool is_concrete_value_class) {
885 return align_metadata_size(header_size() +
886 vtable_length +
887 itable_length +
888 nonstatic_oop_map_size +
889 (is_interface ? (int)sizeof(Klass*) / wordSize : 0) +
890 (is_concrete_value_class ? (int)sizeof(ValueKlass::Members) / wordSize : 0));
891 }
892
893 int InstanceKlass::size() const {
894 return size(vtable_length(),
895 itable_length(),
896 nonstatic_oop_map_size(),
897 is_interface(),
898 is_value_klass());
899 }
900
901 klassItable InstanceKlass::itable() const {
902 return klassItable(const_cast<InstanceKlass*>(this));
903 }
904
905 // JVMTI spec thinks there are signers and protection domain in the
906 // instanceKlass. These accessors pretend these fields are there.
907 // The hprof specification also thinks these fields are in InstanceKlass.
908 oop InstanceKlass::protection_domain() const {
909 // return the protection_domain from the mirror
910 return java_lang_Class::protection_domain(java_mirror());
911 }
912
913 objArrayOop InstanceKlass::signers() const {
914 // return the signers from the mirror
915 return java_lang_Class::signers(java_mirror());
916 }
917
918 oop InstanceKlass::init_lock() const {
919 // return the init lock from the mirror
920 oop lock = java_lang_Class::init_lock(java_mirror());
921 // Prevent reordering with any access of initialization state
922 OrderAccess::loadload();
923 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
924 "only fully initialized state can have a null lock");
925 return lock;
926 }
927
928 // Set the initialization lock to null so the object can be GC'ed. Any racing
929 // threads to get this lock will see a null lock and will not lock.
930 // That's okay because they all check for initialized state after getting
931 // the lock and return. For preempted vthreads we keep the oop protected
932 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()).
933 void InstanceKlass::fence_and_clear_init_lock() {
934 // make sure previous stores are all done, notably the init_state.
935 OrderAccess::storestore();
936 java_lang_Class::clear_init_lock(java_mirror());
937 assert(!is_not_initialized(), "class must be initialized now");
938 }
939
940 class PreemptableInitCall {
941 JavaThread* _thread;
942 bool _previous;
943 DEBUG_ONLY(InstanceKlass* _previous_klass;)
944 public:
945 PreemptableInitCall(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
946 _previous = thread->at_preemptable_init();
947 _thread->set_at_preemptable_init(true);
948 DEBUG_ONLY(_previous_klass = _thread->preempt_init_klass();)
949 DEBUG_ONLY(_thread->set_preempt_init_klass(ik));
950 }
951 ~PreemptableInitCall() {
952 _thread->set_at_preemptable_init(_previous);
953 DEBUG_ONLY(_thread->set_preempt_init_klass(_previous_klass));
954 }
955 };
956
957 void InstanceKlass::initialize_preemptable(TRAPS) {
958 if (this->should_be_initialized()) {
959 PreemptableInitCall pic(THREAD, this);
960 initialize_impl(THREAD);
961 } else {
962 assert(is_initialized(), "sanity check");
963 }
964 }
965
966 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
967 // process. The step comments refers to the procedure described in that section.
968 // Note: implementation moved to static method to expose the this pointer.
969 void InstanceKlass::initialize(TRAPS) {
970 if (this->should_be_initialized()) {
971 initialize_impl(CHECK);
972 // Note: at this point the class may be initialized
973 // OR it may be in the state of being initialized
974 // in case of recursive initialization!
975 } else {
976 assert(is_initialized(), "sanity check");
977 }
978 }
979
980 #ifdef ASSERT
981 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
982 assert(has_aot_initialized_mirror(), "must be");
983
984 InstanceKlass* s = super();
985 if (s != nullptr) {
986 DEBUG_ONLY(ResourceMark rm);
987 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
988 s->external_name(), external_name());
989 s->assert_no_clinit_will_run_for_aot_initialized_class();
990 }
991
992 Array<InstanceKlass*>* interfaces = local_interfaces();
993 int len = interfaces->length();
994 for (int i = 0; i < len; i++) {
995 InstanceKlass* intf = interfaces->at(i);
996 if (!intf->is_initialized()) {
997 ResourceMark rm;
998 // Note: an interface needs to be marked as is_initialized() only if
999 // - it has a <clinit>
1000 // - it has declared a default method.
1001 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
1002 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
1003 intf->external_name(), external_name());
1004 }
1005 }
1006 }
1007 #endif
1008
1009 #if INCLUDE_CDS
1010 // early_init -- we are moving this class into the fully_initialized state before the
1011 // JVM is able to execute any bytecodes. See AOTLinkedClassBulkLoader::is_initializing_classes_early().
1012 void InstanceKlass::initialize_with_aot_initialized_mirror(bool early_init, TRAPS) {
1013 assert(has_aot_initialized_mirror(), "must be");
1014 assert(CDSConfig::is_loading_heap(), "must be");
1015 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
1016 assert_no_clinit_will_run_for_aot_initialized_class();
1017
1018 if (is_initialized()) {
1019 return;
1020 }
1021
1022 if (log_is_enabled(Info, aot, init)) {
1023 ResourceMark rm;
1024 log_info(aot, init)("%s (aot-inited%s)", external_name(), early_init ? ", early" : "");
1025 }
1026
1027 if (is_runtime_setup_required()) {
1028 assert(!early_init, "must not call");
1029 // Need to take the slow path, which will call the runtimeSetup() function instead
1030 // of <clinit>
1031 initialize(CHECK);
1032 return;
1033 }
1034
1035 LogTarget(Info, class, init) lt;
1036 if (lt.is_enabled()) {
1037 ResourceMark rm(THREAD);
1038 LogStream ls(lt);
1039 ls.print("%d Initializing ", call_class_initializer_counter++);
1040 name()->print_value_on(&ls);
1041 ls.print_cr("(aot-inited) (" PTR_FORMAT ") by thread \"%s\"",
1042 p2i(this), THREAD->name());
1043 }
1044
1045 if (early_init) {
1046 precond(AOTLinkedClassBulkLoader::is_initializing_classes_early());
1047 precond(is_linked());
1048 precond(init_thread() == nullptr);
1049 set_init_state(fully_initialized);
1050 fence_and_clear_init_lock();
1051 return;
1052 }
1053
1054 link_class(CHECK);
1055
1056 #ifdef ASSERT
1057 {
1058 Handle h_init_lock(THREAD, init_lock());
1059 ObjectLocker ol(h_init_lock, THREAD);
1060 assert(!is_initialized(), "sanity");
1061 assert(!is_being_initialized(), "sanity");
1062 assert(!is_in_error_state(), "sanity");
1063 }
1064 #endif
1065
1066 set_init_thread(THREAD);
1067 set_initialization_state_and_notify(fully_initialized, CHECK);
1068 }
1069 #endif
1070
1071 bool InstanceKlass::verify_code(TRAPS) {
1072 // 1) Verify the bytecodes
1073 return Verifier::verify(this, should_verify_class(), THREAD);
1074 }
1075
1076 static void load_classes_from_loadable_descriptors_attribute(InstanceKlass *ik, TRAPS) {
1077 if (ik->loadable_descriptors() != Universe::the_empty_short_array() && PreloadClasses) {
1078 ResourceMark rm(THREAD);
1079 HandleMark hm(THREAD);
1080 for (int i = 0; i < ik->loadable_descriptors()->length(); i++) {
1081 Symbol* sig = ik->constants()->symbol_at(ik->loadable_descriptors()->at(i));
1082 if (!Signature::has_envelope(sig)) continue;
1083 TempNewSymbol class_name = Signature::strip_envelope(sig);
1084 if (class_name == ik->name()) continue;
1085 log_info(class, preload)("Preloading of class %s during linking of class %s "
1086 "because the class is listed in the LoadableDescriptors attribute",
1087 sig->as_C_string(), ik->name()->as_C_string());
1088 oop loader = ik->class_loader();
1089 Klass* klass = nullptr;
1090
1091 if (CDSConfig::is_using_aot_linked_classes() && ik->in_aot_cache() && !ik->defined_by_other_loaders()) {
1092 // + We come to here during AOTLinkedClassBulkLoader::link_classes() and it's too early to
1093 // execute any Java code.
1094 // + All loadable descriptors that can be resolved would have been resolved during the AOT assembly
1095 // phase, and would have been loaded earlier by AOTLinkedClassBulkLoader, so they can be found in
1096 // the system dictionary.
1097 // + If no class of the given name have been loaded yet, it's most likely because the class
1098 // is missing from JAR files. Just ignore it.
1099 klass = SystemDictionary::find_instance_or_array_klass(THREAD, class_name, Handle(THREAD, loader));
1100 } else {
1101 klass = SystemDictionary::resolve_or_null(class_name,
1102 Handle(THREAD, loader), THREAD);
1103 }
1104 if (HAS_PENDING_EXCEPTION) {
1105 CLEAR_PENDING_EXCEPTION;
1106 }
1107 if (klass != nullptr) {
1108 log_info(class, preload)("Preloading of class %s during linking of class %s "
1109 "(cause: LoadableDescriptors attribute) succeeded",
1110 class_name->as_C_string(), ik->name()->as_C_string());
1111 if (!klass->is_value_klass()) {
1112 // Non value classes are allowed by the current spec, but it could be an indication
1113 // of an issue so let's log a warning
1114 log_info(class, preload)("Preloading of class %s during linking of class %s "
1115 "(cause: LoadableDescriptors attribute) but loaded class is not a value class",
1116 class_name->as_C_string(), ik->name()->as_C_string());
1117 }
1118 } else {
1119 log_info(class, preload)("Preloading of class %s during linking of class %s "
1120 "(cause: LoadableDescriptors attribute) failed",
1121 class_name->as_C_string(), ik->name()->as_C_string());
1122 }
1123 }
1124 }
1125 }
1126
1127 void InstanceKlass::link_class(TRAPS) {
1128 assert(is_loaded(), "must be loaded");
1129 if (!is_linked()) {
1130 link_class_impl(CHECK);
1131 }
1132 }
1133
1134 // Called to verify that a class can link during initialization, without
1135 // throwing a VerifyError.
1136 bool InstanceKlass::link_class_or_fail(TRAPS) {
1137 assert(is_loaded(), "must be loaded");
1138 if (!is_linked()) {
1139 link_class_impl(CHECK_false);
1140 }
1141 return is_linked();
1142 }
1143
1144 bool InstanceKlass::link_class_impl(TRAPS) {
1145 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
1146 // This is for CDS static dump only -- we use the in_error_state to indicate that
1147 // the class has failed verification. Throwing the NoClassDefFoundError here is just
1148 // a convenient way to stop repeat attempts to verify the same (bad) class.
1149 //
1150 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
1151 // if we are executing Java code. This is not a problem for CDS dumping phase since
1152 // it doesn't execute any Java code.
1153 ResourceMark rm(THREAD);
1154 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1155 Exceptions::fthrow(THREAD_AND_LOCATION,
1156 vmSymbols::java_lang_NoClassDefFoundError(),
1157 "Class %s, or one of its supertypes, failed class initialization",
1158 external_name());
1159 return false;
1160 }
1161 // return if already verified
1162 if (is_linked()) {
1163 return true;
1164 }
1165
1166 // Timing
1167 // timer handles recursion
1168 JavaThread* jt = THREAD;
1169
1170 // link super class before linking this class
1171 InstanceKlass* super_klass = super();
1172 if (super_klass != nullptr) {
1173 if (super_klass->is_interface()) { // check if super class is an interface
1174 ResourceMark rm(THREAD);
1175 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1176 Exceptions::fthrow(
1177 THREAD_AND_LOCATION,
1178 vmSymbols::java_lang_IncompatibleClassChangeError(),
1179 "class %s has interface %s as super class",
1180 external_name(),
1181 super_klass->external_name()
1182 );
1183 return false;
1184 }
1185
1186 super_klass->link_class_impl(CHECK_false);
1187 }
1188
1189 // link all interfaces implemented by this class before linking this class
1190 Array<InstanceKlass*>* interfaces = local_interfaces();
1191 int num_interfaces = interfaces->length();
1192 for (int index = 0; index < num_interfaces; index++) {
1193 InstanceKlass* interk = interfaces->at(index);
1194 interk->link_class_impl(CHECK_false);
1195 }
1196
1197 if (Arguments::is_valhalla_enabled()) {
1198 // Aggressively preloading all classes from the LoadableDescriptors attribute
1199 // so value classes can be scalarized in the calling conventions computed below
1200 load_classes_from_loadable_descriptors_attribute(this, THREAD);
1201 assert(!HAS_PENDING_EXCEPTION, "Shouldn't have pending exceptions from call above");
1202 }
1203
1204 // in case the class is linked in the process of linking its superclasses
1205 if (is_linked()) {
1206 return true;
1207 }
1208
1209 // trace only the link time for this klass that includes
1210 // the verification time
1211 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1212 ClassLoader::perf_class_link_selftime(),
1213 ClassLoader::perf_classes_linked(),
1214 jt->get_thread_stat()->perf_recursion_counts_addr(),
1215 jt->get_thread_stat()->perf_timers_addr(),
1216 PerfClassTraceTime::CLASS_LINK);
1217
1218 // verification & rewriting
1219 {
1220 HandleMark hm(THREAD);
1221 Handle h_init_lock(THREAD, init_lock());
1222 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false);
1223 // Don't allow preemption if we link/initialize classes below,
1224 // since that would release this monitor while we are in the
1225 // middle of linking this class.
1226 NoPreemptMark npm(THREAD);
1227
1228 // rewritten will have been set if loader constraint error found
1229 // on an earlier link attempt
1230 // don't verify or rewrite if already rewritten
1231 //
1232
1233 if (!is_linked()) {
1234 if (!is_rewritten()) {
1235 if (in_aot_cache()) {
1236 assert(!verified_at_dump_time(), "must be");
1237 }
1238 {
1239 bool verify_ok = verify_code(THREAD);
1240 if (!verify_ok) {
1241 return false;
1242 }
1243 }
1244
1245 // Just in case a side-effect of verify linked this class already
1246 // (which can sometimes happen since the verifier loads classes
1247 // using custom class loaders, which are free to initialize things)
1248 if (is_linked()) {
1249 return true;
1250 }
1251
1252 // also sets rewritten
1253 rewrite_class(CHECK_false);
1254 } else if (in_aot_cache()) {
1255 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1256 }
1257
1258 // relocate jsrs and link methods after they are all rewritten
1259 link_methods(CHECK_false);
1260
1261 // Initialize the vtable and interface table after
1262 // methods have been rewritten since rewrite may
1263 // fabricate new Method*s.
1264 // also does loader constraint checking
1265 //
1266 // initialize_vtable and initialize_itable need to be rerun
1267 // for a shared class if
1268 // 1) the class is loaded by custom class loader or
1269 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1270 // 3) the class was not verified during dump time
1271 bool need_init_table = true;
1272 if (in_aot_cache() && verified_at_dump_time() &&
1273 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1274 need_init_table = false;
1275 }
1276 if (need_init_table) {
1277 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1278 itable().initialize_itable_and_check_constraints(CHECK_false);
1279 }
1280 #ifdef ASSERT
1281 vtable().verify(tty, true);
1282 // In case itable verification is ever added.
1283 // itable().verify(tty, true);
1284 #endif
1285 if (Universe::is_fully_initialized()) {
1286 DeoptimizationScope deopt_scope;
1287 {
1288 // Now mark all code that assumes the class is not linked.
1289 // Set state under the Compile_lock also.
1290 MutexLocker ml(THREAD, Compile_lock);
1291
1292 set_init_state(linked);
1293 CodeCache::mark_dependents_on(&deopt_scope, this);
1294 }
1295 // Perform the deopt handshake outside Compile_lock.
1296 deopt_scope.deoptimize_marked();
1297 } else {
1298 set_init_state(linked);
1299 }
1300 if (JvmtiExport::should_post_class_prepare()) {
1301 JvmtiExport::post_class_prepare(THREAD, this);
1302 }
1303 }
1304 }
1305
1306 if (log_is_enabled(Info, class, link)) {
1307 ResourceMark rm(THREAD);
1308 log_info(class, link)("Linked class %s", external_name());
1309 }
1310
1311 return true;
1312 }
1313
1314 // Rewrite the byte codes of all of the methods of a class.
1315 // The rewriter must be called exactly once. Rewriting must happen after
1316 // verification but before the first method of the class is executed.
1317 void InstanceKlass::rewrite_class(TRAPS) {
1318 assert(is_loaded(), "must be loaded");
1319 if (is_rewritten()) {
1320 assert(in_aot_cache(), "rewriting an unshared class?");
1321 return;
1322 }
1323 Rewriter::rewrite(this, CHECK);
1324 set_rewritten();
1325 }
1326
1327 // Now relocate and link method entry points after class is rewritten.
1328 // This is outside is_rewritten flag. In case of an exception, it can be
1329 // executed more than once.
1330 void InstanceKlass::link_methods(TRAPS) {
1331 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1332
1333 int len = methods()->length();
1334 for (int i = len-1; i >= 0; i--) {
1335 methodHandle m(THREAD, methods()->at(i));
1336
1337 // Set up method entry points for compiler and interpreter .
1338 m->link_method(m, CHECK);
1339 }
1340 }
1341
1342 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1343 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1344 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1345 for (int i = 0; i < local_interfaces()->length(); ++i) {
1346 InstanceKlass* ik = local_interfaces()->at(i);
1347
1348 // Initialization is depth first search ie. we start with top of the inheritance tree
1349 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1350 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1351 if (ik->has_nonstatic_concrete_methods()) {
1352 ik->initialize_super_interfaces(CHECK);
1353 }
1354
1355 // Only initialize() interfaces that "declare" concrete methods.
1356 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1357 ik->initialize(CHECK);
1358 }
1359 }
1360 }
1361
1362 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1363 static InitializationErrorTable* _initialization_error_table;
1364
1365 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1366 // Create the same exception with a message indicating the thread name,
1367 // and the StackTraceElements.
1368 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1369 ResourceMark rm(current);
1370 if (init_error.is_null()) {
1371 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1372
1373 // We failed to create the new exception, most likely due to either out-of-memory or
1374 // a stackoverflow error. If the original exception was either of those then we save
1375 // the shared, pre-allocated, stackless, instance of that exception.
1376 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1377 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1378 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1379 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1380 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1381 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1382 } else {
1383 return;
1384 }
1385 }
1386
1387 MutexLocker ml(current, ClassInitError_lock);
1388 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1389 bool created;
1390 if (_initialization_error_table == nullptr) {
1391 _initialization_error_table = new (mtClass) InitializationErrorTable();
1392 }
1393 _initialization_error_table->put_if_absent(this, elem, &created);
1394 assert(created, "Initialization is single threaded");
1395 log_trace(class, init)("Initialization error added for class %s", external_name());
1396 }
1397
1398 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1399 MutexLocker ml(current, ClassInitError_lock);
1400 if (_initialization_error_table == nullptr) {
1401 return nullptr;
1402 }
1403 OopHandle* h = _initialization_error_table->get(this);
1404 return (h != nullptr) ? h->resolve() : nullptr;
1405 }
1406
1407 // Need to remove entries for unloaded classes.
1408 void InstanceKlass::clean_initialization_error_table() {
1409 struct InitErrorTableCleaner {
1410 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1411 if (!ik->is_loader_alive()) {
1412 h.release(Universe::vm_global());
1413 return true;
1414 } else {
1415 return false;
1416 }
1417 }
1418 };
1419
1420 assert_locked_or_safepoint(ClassInitError_lock);
1421 InitErrorTableCleaner cleaner;
1422 if (_initialization_error_table != nullptr) {
1423 _initialization_error_table->unlink(&cleaner);
1424 }
1425 }
1426
1427 class ThreadWaitingForClassInit : public StackObj {
1428 JavaThread* _thread;
1429 public:
1430 ThreadWaitingForClassInit(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
1431 _thread->set_class_to_be_initialized(ik);
1432 }
1433 ~ThreadWaitingForClassInit() {
1434 _thread->set_class_to_be_initialized(nullptr);
1435 }
1436 };
1437
1438 void InstanceKlass::initialize_impl(TRAPS) {
1439 HandleMark hm(THREAD);
1440
1441 // Make sure klass is linked (verified) before initialization
1442 // A class could already be verified, since it has been reflected upon.
1443 link_class(CHECK);
1444
1445 DTRACE_CLASSINIT_PROBE(required, -1);
1446
1447 bool wait = false;
1448
1449 JavaThread* jt = THREAD;
1450
1451 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1452
1453 // refer to the JVM book page 47 for description of steps
1454 // Step 1
1455 {
1456 Handle h_init_lock(THREAD, init_lock());
1457 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE);
1458
1459 // Step 2
1460 // If we were to use wait() instead of waitInterruptibly() then
1461 // we might end up throwing IE from link/symbol resolution sites
1462 // that aren't expected to throw. This would wreak havoc. See 6320309.
1463 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1464 if (debug_logging_enabled) {
1465 ResourceMark rm(jt);
1466 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1467 jt->name(), external_name(), init_thread_name());
1468 }
1469 wait = true;
1470 ThreadWaitingForClassInit twcl(THREAD, this);
1471 ol.wait_uninterruptibly(CHECK_PREEMPTABLE);
1472 }
1473
1474 // Step 3
1475 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1476 if (debug_logging_enabled) {
1477 ResourceMark rm(jt);
1478 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1479 jt->name(), external_name());
1480 }
1481 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1482 return;
1483 }
1484
1485 // Step 4
1486 if (is_initialized()) {
1487 if (debug_logging_enabled) {
1488 ResourceMark rm(jt);
1489 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1490 jt->name(), external_name());
1491 }
1492 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1493 return;
1494 }
1495
1496 // Step 5
1497 if (is_in_error_state()) {
1498 if (debug_logging_enabled) {
1499 ResourceMark rm(jt);
1500 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1501 jt->name(), external_name());
1502 }
1503
1504 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1505 ResourceMark rm(THREAD);
1506 Handle cause(THREAD, get_initialization_error(THREAD));
1507
1508 stringStream ss;
1509 ss.print("Could not initialize class %s", external_name());
1510 if (cause.is_null()) {
1511 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1512 } else {
1513 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1514 ss.as_string(), cause);
1515 }
1516 } else {
1517
1518 // Step 6
1519 set_init_state(being_initialized);
1520 set_init_thread(jt);
1521 if (debug_logging_enabled) {
1522 ResourceMark rm(jt);
1523 log_debug(class, init)("Thread \"%s\" is initializing %s",
1524 jt->name(), external_name());
1525 }
1526 }
1527 }
1528
1529 // Block preemption once we are the initializer thread. Unmounting now
1530 // would complicate the reentrant case (identity is platform thread).
1531 NoPreemptMark npm(THREAD);
1532
1533 // Pre-allocating an all-zero value to be used to reset nullable flat storages
1534 if (is_value_klass()) {
1535 ValueKlass* vk = ValueKlass::cast(this);
1536 if (vk->supports_nullable_layouts()) {
1537 oop val = vk->allocate_instance(THREAD);
1538 if (HAS_PENDING_EXCEPTION) {
1539 Handle e(THREAD, PENDING_EXCEPTION);
1540 CLEAR_PENDING_EXCEPTION;
1541 {
1542 EXCEPTION_MARK;
1543 add_initialization_error(THREAD, e);
1544 // Locks object, set state, and notify all waiting threads
1545 set_initialization_state_and_notify(initialization_error, THREAD);
1546 CLEAR_PENDING_EXCEPTION;
1547 }
1548 THROW_OOP(e());
1549 }
1550 vk->set_null_reset_value(val);
1551 }
1552 }
1553
1554 // Step 7
1555 // Next, if C is a class rather than an interface, initialize it's super class and super
1556 // interfaces.
1557 if (!is_interface()) {
1558 Klass* super_klass = super();
1559 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1560 super_klass->initialize(THREAD);
1561 }
1562 // If C implements any interface that declares a non-static, concrete method,
1563 // the initialization of C triggers initialization of its super interfaces.
1564 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1565 // having a superinterface that declares, non-static, concrete methods
1566 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1567 initialize_super_interfaces(THREAD);
1568 }
1569
1570 // If any exceptions, complete abruptly, throwing the same exception as above.
1571 if (HAS_PENDING_EXCEPTION) {
1572 Handle e(THREAD, PENDING_EXCEPTION);
1573 CLEAR_PENDING_EXCEPTION;
1574 {
1575 EXCEPTION_MARK;
1576 add_initialization_error(THREAD, e);
1577 // Locks object, set state, and notify all waiting threads
1578 set_initialization_state_and_notify(initialization_error, THREAD);
1579 CLEAR_PENDING_EXCEPTION;
1580 }
1581 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1582 THROW_OOP(e());
1583 }
1584 }
1585
1586
1587 // Step 8
1588 {
1589 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1590 if (class_initializer() != nullptr) {
1591 // Timer includes any side effects of class initialization (resolution,
1592 // etc), but not recursive entry into call_class_initializer().
1593 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1594 ClassLoader::perf_class_init_selftime(),
1595 ClassLoader::perf_classes_inited(),
1596 jt->get_thread_stat()->perf_recursion_counts_addr(),
1597 jt->get_thread_stat()->perf_timers_addr(),
1598 PerfClassTraceTime::CLASS_CLINIT);
1599 call_class_initializer(THREAD);
1600 } else {
1601 // The elapsed time is so small it's not worth counting.
1602 if (UsePerfData) {
1603 ClassLoader::perf_classes_inited()->inc();
1604 }
1605 call_class_initializer(THREAD);
1606 }
1607
1608 if (has_strict_static_fields() && !HAS_PENDING_EXCEPTION && !ReplayCompiles) {
1609 // Step 9 also verifies that strict static fields have been initialized.
1610 // Status bits were set in ClassFileParser::post_process_parsed_stream.
1611 // After <clinit>, bits must all be clear, or else we must throw an error.
1612 // This is an extremely fast check, so we won't bother with a timer.
1613 assert(fields_status() != nullptr, "");
1614 Symbol* bad_strict_static = nullptr;
1615 for (int index = 0; index < fields_status()->length(); index++) {
1616 // Very fast loop over single byte array looking for a set bit.
1617 if (fields_status()->adr_at(index)->is_strict_static_unset()) {
1618 // This strict static field has not been set by the class initializer.
1619 // Note that in the common no-error case, we read no field metadata.
1620 // We only unpack it when we need to report an error.
1621 FieldInfo fi = field(index);
1622 bad_strict_static = fi.name(constants());
1623 if (debug_logging_enabled) {
1624 ResourceMark rm(jt);
1625 const char* msg = format_strict_static_message(bad_strict_static);
1626 log_debug(class, init)("%s", msg);
1627 } else {
1628 // If we are not logging, do not bother to look for a second offense.
1629 break;
1630 }
1631 }
1632 }
1633 if (bad_strict_static != nullptr) {
1634 throw_strict_static_exception(bad_strict_static, "is unset after initialization of", THREAD);
1635 }
1636 }
1637 }
1638
1639 // Step 9
1640 if (!HAS_PENDING_EXCEPTION) {
1641 set_initialization_state_and_notify(fully_initialized, CHECK);
1642 DEBUG_ONLY(vtable().verify(tty, true);)
1643 CompilationPolicy::replay_training_at_init(this, THREAD);
1644 }
1645 else {
1646 // Step 10 and 11
1647 Handle e(THREAD, PENDING_EXCEPTION);
1648 CLEAR_PENDING_EXCEPTION;
1649 // JVMTI has already reported the pending exception
1650 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1651 JvmtiExport::clear_detected_exception(jt);
1652 {
1653 EXCEPTION_MARK;
1654 add_initialization_error(THREAD, e);
1655 set_initialization_state_and_notify(initialization_error, THREAD);
1656 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1657 // JVMTI has already reported the pending exception
1658 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1659 JvmtiExport::clear_detected_exception(jt);
1660 }
1661 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1662 if (e->is_a(vmClasses::Error_klass())) {
1663 THROW_OOP(e());
1664 } else {
1665 JavaCallArguments args(e);
1666 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1667 vmSymbols::throwable_void_signature(),
1668 &args);
1669 }
1670 }
1671 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1672 }
1673
1674
1675 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1676 Handle h_init_lock(THREAD, init_lock());
1677 if (h_init_lock() != nullptr) {
1678 ObjectLocker ol(h_init_lock, THREAD);
1679 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1680 set_init_state(state);
1681 fence_and_clear_init_lock();
1682 ol.notify_all(CHECK);
1683 } else {
1684 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1685 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1686 set_init_state(state);
1687 }
1688 }
1689
1690 void InstanceKlass::notify_strict_static_access(int field_index, bool is_writing, TRAPS) {
1691 guarantee(field_index >= 0 && field_index < fields_status()->length(), "valid field index");
1692 DEBUG_ONLY(FieldInfo debugfi = field(field_index));
1693 assert(debugfi.access_flags().is_strict(), "");
1694 assert(debugfi.access_flags().is_static(), "");
1695 FieldStatus& fs = *fields_status()->adr_at(field_index);
1696 LogTarget(Trace, class, init) lt;
1697 if (lt.is_enabled()) {
1698 ResourceMark rm(THREAD);
1699 LogStream ls(lt);
1700 FieldInfo fi = field(field_index);
1701 ls.print("notify %s %s %s%s ",
1702 external_name(), is_writing? "Write" : "Read",
1703 fs.is_strict_static_unset() ? "Unset" : "(set)",
1704 fs.is_strict_static_unread() ? "+Unread" : "");
1705 fi.print(&ls, constants());
1706 }
1707 if (fs.is_strict_static_unset()) {
1708 assert(fs.is_strict_static_unread(), "ClassFileParser resp.");
1709 // If it is not set, there are only two reasonable things we can do here:
1710 // - mark it set if this is putstatic
1711 // - throw an error (Read-Before-Write) if this is getstatic
1712
1713 // The unset state is (or should be) transient, and observable only in one
1714 // thread during the execution of <clinit>. Something is wrong here as this
1715 // should not be possible
1716 guarantee(is_reentrant_initialization(THREAD), "unscoped access to strict static");
1717 if (is_writing) {
1718 // clear the "unset" bit, since the field is actually going to be written
1719 fs.update_strict_static_unset(false);
1720 } else {
1721 // throw an IllegalStateException, since we are reading before writing
1722 // see also InstanceKlass::initialize_impl, Step 8 (at end)
1723 Symbol* bad_strict_static = field(field_index).name(constants());
1724 throw_strict_static_exception(bad_strict_static, "is unset before first read in", CHECK);
1725 }
1726 } else {
1727 // Ensure no write after read for final strict statics
1728 FieldInfo fi = field(field_index);
1729 bool is_final = fi.access_flags().is_final();
1730 if (is_final) {
1731 // no final write after read, so observing a constant freezes it, as if <clinit> ended early
1732 // (maybe we could trust the constant a little earlier, before <clinit> ends)
1733 if (is_writing && !fs.is_strict_static_unread()) {
1734 Symbol* bad_strict_static = fi.name(constants());
1735 throw_strict_static_exception(bad_strict_static, "is set after read (as final) in", CHECK);
1736 } else if (!is_writing && fs.is_strict_static_unread()) {
1737 fs.update_strict_static_unread(false);
1738 }
1739 }
1740 }
1741 }
1742
1743 void InstanceKlass::throw_strict_static_exception(Symbol* field_name, const char* when, TRAPS) {
1744 ResourceMark rm(THREAD);
1745 const char* msg = format_strict_static_message(field_name, when);
1746 THROW_MSG(vmSymbols::java_lang_IllegalStateException(), msg);
1747 }
1748
1749 const char* InstanceKlass::format_strict_static_message(Symbol* field_name, const char* when) {
1750 stringStream ss;
1751 ss.print("Strict static \"%s\" %s %s",
1752 field_name->as_C_string(),
1753 when == nullptr ? "is unset in" : when,
1754 external_name());
1755 return ss.as_string();
1756 }
1757
1758 bool InstanceKlass::has_strict_instance_fields_in_hierarchy() const {
1759 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->java_super()) {
1760 if (ik->has_strict_instance_fields()) {
1761 return true;
1762 }
1763 }
1764 return false;
1765 }
1766
1767 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1768 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1769 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1770 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1771
1772 DeoptimizationScope deopt_scope;
1773 {
1774 MutexLocker ml(current, Compile_lock);
1775
1776 set_init_state(InstanceKlass::loaded);
1777 // make sure init_state store is already done.
1778 // The compiler reads the hierarchy outside of the Compile_lock.
1779 // Access ordering is used to add to hierarchy.
1780
1781 // Link into hierarchy.
1782 append_to_sibling_list(); // add to superklass/sibling list
1783 process_interfaces(); // handle all "implements" declarations
1784
1785 // Now mark all code that depended on old class hierarchy.
1786 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1787 if (Universe::is_fully_initialized()) {
1788 CodeCache::mark_dependents_on(&deopt_scope, this);
1789 }
1790 }
1791 // Perform the deopt handshake outside Compile_lock.
1792 deopt_scope.deoptimize_marked();
1793 }
1794
1795
1796 InstanceKlass* InstanceKlass::implementor() const {
1797 InstanceKlass* volatile* ik = adr_implementor();
1798 if (ik == nullptr) {
1799 return nullptr;
1800 } else {
1801 // This load races with inserts, and therefore needs acquire.
1802 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1803 if (ikls != nullptr && !ikls->is_loader_alive()) {
1804 return nullptr; // don't return unloaded class
1805 } else {
1806 return ikls;
1807 }
1808 }
1809 }
1810
1811
1812 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1813 assert_locked_or_safepoint(Compile_lock);
1814 assert(is_interface(), "not interface");
1815 InstanceKlass* volatile* addr = adr_implementor();
1816 assert(addr != nullptr, "null addr");
1817 if (addr != nullptr) {
1818 AtomicAccess::release_store(addr, ik);
1819 }
1820 }
1821
1822 int InstanceKlass::nof_implementors() const {
1823 InstanceKlass* ik = implementor();
1824 if (ik == nullptr) {
1825 return 0;
1826 } else if (ik != this) {
1827 return 1;
1828 } else {
1829 return 2;
1830 }
1831 }
1832
1833 // The embedded _implementor field can only record one implementor.
1834 // When there are more than one implementors, the _implementor field
1835 // is set to the interface Klass* itself. Following are the possible
1836 // values for the _implementor field:
1837 // null - no implementor
1838 // implementor Klass* - one implementor
1839 // self - more than one implementor
1840 //
1841 // The _implementor field only exists for interfaces.
1842 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1843 if (Universe::is_fully_initialized()) {
1844 assert_lock_strong(Compile_lock);
1845 }
1846 assert(is_interface(), "not interface");
1847 // Filter out my subinterfaces.
1848 // (Note: Interfaces are never on the subklass list.)
1849 if (ik->is_interface()) return;
1850
1851 // Filter out subclasses whose supers already implement me.
1852 // (Note: CHA must walk subclasses of direct implementors
1853 // in order to locate indirect implementors.)
1854 InstanceKlass* super_ik = ik->super();
1855 if (super_ik != nullptr && super_ik->implements_interface(this))
1856 // We only need to check one immediate superclass, since the
1857 // implements_interface query looks at transitive_interfaces.
1858 // Any supers of the super have the same (or fewer) transitive_interfaces.
1859 return;
1860
1861 InstanceKlass* iklass = implementor();
1862 if (iklass == nullptr) {
1863 set_implementor(ik);
1864 } else if (iklass != this && iklass != ik) {
1865 // There is already an implementor. Use itself as an indicator of
1866 // more than one implementors.
1867 set_implementor(this);
1868 }
1869
1870 // The implementor also implements the transitive_interfaces
1871 for (int index = 0; index < local_interfaces()->length(); index++) {
1872 local_interfaces()->at(index)->add_implementor(ik);
1873 }
1874 }
1875
1876 void InstanceKlass::init_implementor() {
1877 if (is_interface()) {
1878 set_implementor(nullptr);
1879 }
1880 }
1881
1882
1883 void InstanceKlass::process_interfaces() {
1884 // link this class into the implementors list of every interface it implements
1885 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1886 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1887 InstanceKlass* interf = local_interfaces()->at(i);
1888 assert(interf->is_interface(), "expected interface");
1889 interf->add_implementor(this);
1890 }
1891 }
1892
1893 bool InstanceKlass::can_be_primary_super_slow() const {
1894 if (is_interface())
1895 return false;
1896 else
1897 return Klass::can_be_primary_super_slow();
1898 }
1899
1900 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1901 Array<InstanceKlass*>* transitive_interfaces) {
1902 // The secondaries are the implemented interfaces.
1903 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1904 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1905 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1906 int num_secondaries = num_extra_slots + interfaces->length();
1907 if (num_secondaries == 0) {
1908 // Must share this for correct bootstrapping!
1909 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1910 return nullptr;
1911 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1912 // We will reuse the transitive interfaces list if we're certain
1913 // it's in hash order.
1914 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1915 set_secondary_supers(interfaces, bitmap);
1916 return nullptr;
1917 }
1918 // Copy transitive interfaces to a temporary growable array to be constructed
1919 // into the secondary super list with extra slots.
1920 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1921 for (int i = 0; i < interfaces->length(); i++) {
1922 secondaries->push(interfaces->at(i));
1923 }
1924 return secondaries;
1925 }
1926
1927 bool InstanceKlass::implements_interface(Klass* k) const {
1928 if (this == k) return true;
1929 assert(k->is_interface(), "should be an interface class");
1930 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1931 if (transitive_interfaces()->at(i) == k) {
1932 return true;
1933 }
1934 }
1935 return false;
1936 }
1937
1938 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1939 // Verify direct super interface
1940 if (this == k) return true;
1941 assert(k->is_interface(), "should be an interface class");
1942 for (int i = 0; i < local_interfaces()->length(); i++) {
1943 if (local_interfaces()->at(i) == k) {
1944 return true;
1945 }
1946 }
1947 return false;
1948 }
1949
1950 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1951 if (TraceFinalizerRegistration) {
1952 tty->print("Registered ");
1953 i->print_value_on(tty);
1954 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1955 }
1956 instanceHandle h_i(THREAD, i);
1957 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1958 JavaValue result(T_VOID);
1959 JavaCallArguments args(h_i);
1960 methodHandle mh(THREAD, Universe::finalizer_register_method());
1961 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1962 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1963 return h_i();
1964 }
1965
1966 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1967 assert(!is_abstract() && !is_interface(), "Should not create this object");
1968 size_t size = size_helper(); // Query before forming handle.
1969 return (instanceOop)Universe::heap()->obj_allocate(this, size, THREAD);
1970 }
1971
1972 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1973 Klass* k = java_lang_Class::as_Klass(java_class);
1974 if (k == nullptr) {
1975 ResourceMark rm(THREAD);
1976 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1977 }
1978 InstanceKlass* ik = cast(k);
1979 ik->check_valid_for_instantiation(false, CHECK_NULL);
1980 ik->initialize(CHECK_NULL);
1981 return ik->allocate_instance(THREAD);
1982 }
1983
1984 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1985 return instanceHandle(THREAD, allocate_instance(THREAD));
1986 }
1987
1988 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1989 if (is_interface() || is_abstract()) {
1990 ResourceMark rm(THREAD);
1991 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1992 : vmSymbols::java_lang_InstantiationException(), external_name());
1993 }
1994 if (this == vmClasses::Class_klass()) {
1995 ResourceMark rm(THREAD);
1996 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1997 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1998 }
1999 }
2000
2001 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
2002 // Need load-acquire for lock-free read
2003 if (array_klasses_acquire() == nullptr) {
2004
2005 // Recursively lock array allocation
2006 RecursiveLocker rl(MultiArray_lock, THREAD);
2007
2008 // Check if another thread created the array klass while we were waiting for the lock.
2009 if (array_klasses() == nullptr) {
2010 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
2011 // use 'release' to pair with lock-free load
2012 release_set_array_klasses(k);
2013 }
2014 }
2015
2016 // array_klasses() will always be set at this point
2017 ObjArrayKlass* ak = array_klasses();
2018 assert(ak != nullptr, "should be set");
2019 return ak->array_klass(n, THREAD);
2020 }
2021
2022 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
2023 // Need load-acquire for lock-free read
2024 ObjArrayKlass* oak = array_klasses_acquire();
2025 if (oak == nullptr) {
2026 return nullptr;
2027 } else {
2028 return oak->array_klass_or_null(n);
2029 }
2030 }
2031
2032 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
2033 return array_klass(1, THREAD);
2034 }
2035
2036 ArrayKlass* InstanceKlass::array_klass_or_null() {
2037 return array_klass_or_null(1);
2038 }
2039
2040 Method* InstanceKlass::class_initializer() const {
2041 Method* clinit = find_method(
2042 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
2043 if (clinit != nullptr && clinit->is_class_initializer()) {
2044 return clinit;
2045 }
2046 return nullptr;
2047 }
2048
2049 void InstanceKlass::call_class_initializer(TRAPS) {
2050 if (ReplayCompiles &&
2051 (ReplaySuppressInitializers == 1 ||
2052 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
2053 // Hide the existence of the initializer for the purpose of replaying the compile
2054 return;
2055 }
2056
2057 #if INCLUDE_CDS
2058 // This is needed to ensure the consistency of the archived heap objects.
2059 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
2060 AOTClassInitializer::call_runtime_setup(THREAD, this);
2061 return;
2062 } else if (has_archived_enum_objs()) {
2063 assert(in_aot_cache(), "must be");
2064 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
2065 if (initialized) {
2066 return;
2067 }
2068 }
2069 #endif
2070
2071 methodHandle h_method(THREAD, class_initializer());
2072 assert(!is_initialized(), "we cannot initialize twice");
2073 LogTarget(Info, class, init) lt;
2074 if (lt.is_enabled()) {
2075 ResourceMark rm(THREAD);
2076 LogStream ls(lt);
2077 ls.print("%d Initializing ", call_class_initializer_counter++);
2078 name()->print_value_on(&ls);
2079 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
2080 h_method() == nullptr ? "(no method)" : "", p2i(this),
2081 THREAD->name());
2082 }
2083 if (h_method() != nullptr) {
2084 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
2085 JavaCallArguments args; // No arguments
2086 JavaValue result(T_VOID);
2087 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
2088 }
2089 }
2090
2091 // If a class that implements this interface is initialized, is the JVM required
2092 // to first execute a <clinit> method declared in this interface,
2093 // or (if also_check_supers==true) any of the super types of this interface?
2094 //
2095 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
2096 // an interface, then let SC be its superclass and let SI1, ..., SIn
2097 // be all superinterfaces of C (whether direct or indirect) that
2098 // declare at least one non-abstract, non-static method.
2099 //
2100 // So when an interface is initialized, it does not look at its
2101 // supers. But a proper class will ensure that all of its supers have
2102 // run their <clinit> methods, except that it disregards interfaces
2103 // that lack a non-static concrete method (i.e., a default method).
2104 // Therefore, you should probably call this method only when the
2105 // current class is a super of some proper class, not an interface.
2106 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
2107 assert(is_interface(), "must be");
2108
2109 if (!has_nonstatic_concrete_methods()) {
2110 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
2111 return false;
2112 }
2113
2114 // JVMS 5.5. Initialization
2115 // ...If C is an interface that declares a non-abstract,
2116 // non-static method, the initialization of a class that
2117 // implements C directly or indirectly.
2118 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
2119 return true;
2120 }
2121 if (also_check_supers) {
2122 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2123 for (int i = 0; i < all_ifs->length(); ++i) {
2124 InstanceKlass* super_intf = all_ifs->at(i);
2125 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
2126 return true;
2127 }
2128 }
2129 }
2130 return false;
2131 }
2132
2133 void InstanceKlass::mask_for(const methodHandle& method, int bci,
2134 InterpreterOopMap* entry_for) {
2135 // Lazily create the _oop_map_cache at first request.
2136 // Load_acquire is needed to safely get instance published with CAS by another thread.
2137 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
2138 if (oop_map_cache == nullptr) {
2139 // Try to install new instance atomically.
2140 oop_map_cache = new OopMapCache();
2141 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
2142 if (other != nullptr) {
2143 // Someone else managed to install before us, ditch local copy and use the existing one.
2144 delete oop_map_cache;
2145 oop_map_cache = other;
2146 }
2147 }
2148 // _oop_map_cache is constant after init; lookup below does its own locking.
2149 oop_map_cache->lookup(method, bci, entry_for);
2150 }
2151
2152
2153 FieldInfo InstanceKlass::field(int index) const {
2154 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2155 if (fs.index() == index) {
2156 return fs.to_FieldInfo();
2157 }
2158 }
2159 fatal("Field not found");
2160 return FieldInfo();
2161 }
2162
2163 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2164 JavaFieldStream fs(this);
2165 if (fs.lookup(name, sig)) {
2166 assert(fs.name() == name, "name must match");
2167 assert(fs.signature() == sig, "signature must match");
2168 fd->reinitialize(this, fs.to_FieldInfo());
2169 return true;
2170 }
2171 return false;
2172 }
2173
2174 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd, bool also_internal) const {
2175 if (!also_internal) {
2176 return find_local_field( name, sig, fd);
2177 }
2178
2179 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2180 if (fs.name() == name && fs.signature() == sig) {
2181 fd->reinitialize(this, fs.to_FieldInfo());
2182 return true;
2183 }
2184 }
2185 return false;
2186 }
2187
2188 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2189 const int n = local_interfaces()->length();
2190 for (int i = 0; i < n; i++) {
2191 InstanceKlass* intf1 = local_interfaces()->at(i);
2192 assert(intf1->is_interface(), "just checking type");
2193 // search for field in current interface
2194 if (intf1->find_local_field(name, sig, fd)) {
2195 assert(fd->is_static(), "interface field must be static");
2196 return intf1;
2197 }
2198 // search for field in direct superinterfaces
2199 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
2200 if (intf2 != nullptr) return intf2;
2201 }
2202 // otherwise field lookup fails
2203 return nullptr;
2204 }
2205
2206
2207 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2208 // search order according to newest JVM spec (5.4.3.2, p.167).
2209 // 1) search for field in current klass
2210 if (find_local_field(name, sig, fd)) {
2211 return const_cast<InstanceKlass*>(this);
2212 }
2213 // 2) search for field recursively in direct superinterfaces
2214 { Klass* intf = find_interface_field(name, sig, fd);
2215 if (intf != nullptr) return intf;
2216 }
2217 // 3) apply field lookup recursively if superclass exists
2218 { InstanceKlass* supr = super();
2219 if (supr != nullptr) return supr->find_field(name, sig, fd);
2220 }
2221 // 4) otherwise field lookup fails
2222 return nullptr;
2223 }
2224
2225
2226 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
2227 // search order according to newest JVM spec (5.4.3.2, p.167).
2228 // 1) search for field in current klass
2229 if (find_local_field(name, sig, fd)) {
2230 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
2231 }
2232 // 2) search for field recursively in direct superinterfaces
2233 if (is_static) {
2234 Klass* intf = find_interface_field(name, sig, fd);
2235 if (intf != nullptr) return intf;
2236 }
2237 // 3) apply field lookup recursively if superclass exists
2238 { InstanceKlass* supr = super();
2239 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
2240 }
2241 // 4) otherwise field lookup fails
2242 return nullptr;
2243 }
2244
2245 bool InstanceKlass::contains_field_offset(int offset) {
2246 if (this->is_value_klass()) {
2247 ValueKlass* vk = ValueKlass::cast(this);
2248 return offset >= vk->payload_offset() && offset < (vk->payload_offset() + vk->payload_size_in_bytes());
2249 } else {
2250 fieldDescriptor fd;
2251 return find_field_from_offset(offset, false, &fd);
2252 }
2253 }
2254
2255 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2256 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2257 if (fs.offset() == offset) {
2258 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2259 if (fd->is_static() == is_static) return true;
2260 }
2261 }
2262 return false;
2263 }
2264
2265
2266 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2267 const InstanceKlass* klass = this;
2268 while (klass != nullptr) {
2269 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
2270 return true;
2271 }
2272 klass = klass->super();
2273 }
2274 return false;
2275 }
2276
2277 bool InstanceKlass::find_local_flat_field_containing_offset(int offset, fieldDescriptor* fd) const {
2278 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2279 if (!fs.is_flat()) {
2280 continue;
2281 }
2282
2283 if (fs.offset() > offset) {
2284 continue;
2285 }
2286
2287 const int offset_in_flat_field = offset - fs.offset();
2288 const ValueFieldInfo vfi = value_field_info(fs.index());
2289 const int field_size = vfi.klass()->layout_size_in_bytes(vfi.kind());
2290
2291 assert(LayoutKindHelper::is_flat(vfi.kind()), "Must be flat");
2292
2293 if (offset_in_flat_field < field_size) {
2294 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2295 assert(!fd->is_static(), "Static fields are not flattened");
2296
2297 return true;
2298 }
2299 }
2300
2301 return false;
2302 }
2303
2304 bool InstanceKlass::find_flat_field_containing_offset(int offset, fieldDescriptor* fd) const {
2305 const InstanceKlass* klass = this;
2306 while (klass != nullptr) {
2307 if (klass->find_local_flat_field_containing_offset(offset, fd)) {
2308 return true;
2309 }
2310
2311 klass = klass->super();
2312 }
2313
2314 return false;
2315 }
2316
2317 void InstanceKlass::methods_do(void f(Method* method)) {
2318 // Methods aren't stable until they are loaded. This can be read outside
2319 // a lock through the ClassLoaderData for profiling
2320 // Redefined scratch classes are on the list and need to be cleaned
2321 if (!is_loaded() && !is_scratch_class()) {
2322 return;
2323 }
2324
2325 int len = methods()->length();
2326 for (int index = 0; index < len; index++) {
2327 Method* m = methods()->at(index);
2328 assert(m->is_method(), "must be method");
2329 f(m);
2330 }
2331 }
2332
2333
2334 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2335 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2336 if (fs.access_flags().is_static()) {
2337 fieldDescriptor& fd = fs.field_descriptor();
2338 cl->do_field(&fd);
2339 }
2340 }
2341 }
2342
2343
2344 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2345 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2346 if (fs.access_flags().is_static()) {
2347 fieldDescriptor& fd = fs.field_descriptor();
2348 f(&fd, mirror, CHECK);
2349 }
2350 }
2351 }
2352
2353 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2354 InstanceKlass* super = this->super();
2355 if (super != nullptr) {
2356 super->do_nonstatic_fields(cl);
2357 }
2358 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2359 fieldDescriptor& fd = fs.field_descriptor();
2360 if (!fd.is_static()) {
2361 cl->do_field(&fd);
2362 }
2363 }
2364 }
2365
2366 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2367 return a->offset() - b->offset();
2368 }
2369
2370 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2371 InstanceKlass* super = this->super();
2372 if (super != nullptr) {
2373 super->print_nonstatic_fields(cl);
2374 }
2375 ResourceMark rm;
2376 // In DebugInfo nonstatic fields are sorted by offset.
2377 GrowableArray<FieldInfo> fields_sorted;
2378 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2379 if (!fs.access_flags().is_static()) {
2380 fields_sorted.push(fs.to_FieldInfo());
2381 }
2382 }
2383 int length = fields_sorted.length();
2384 if (length > 0) {
2385 fields_sorted.sort(compare_fields_by_offset);
2386 fieldDescriptor fd;
2387 for (int i = 0; i < length; i++) {
2388 fd.reinitialize(this, fields_sorted.at(i));
2389 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2390 cl->do_field(&fd);
2391 }
2392 }
2393 }
2394
2395 #ifdef ASSERT
2396 static int linear_search(const Array<Method*>* methods,
2397 const Symbol* name,
2398 const Symbol* signature) {
2399 const int len = methods->length();
2400 for (int index = 0; index < len; index++) {
2401 const Method* const m = methods->at(index);
2402 assert(m->is_method(), "must be method");
2403 if (m->signature() == signature && m->name() == name) {
2404 return index;
2405 }
2406 }
2407 return -1;
2408 }
2409 #endif
2410
2411 bool InstanceKlass::_disable_method_binary_search = false;
2412
2413 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2414 int len = methods->length();
2415 int l = 0;
2416 int h = len - 1;
2417 while (l <= h) {
2418 Method* m = methods->at(l);
2419 if (m->name() == name) {
2420 return l;
2421 }
2422 l++;
2423 }
2424 return -1;
2425 }
2426
2427 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2428 if (_disable_method_binary_search) {
2429 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2430 // At the final stage of dynamic dumping, the methods array may not be sorted
2431 // by ascending addresses of their names, so we can't use binary search anymore.
2432 // However, methods with the same name are still laid out consecutively inside the
2433 // methods array, so let's look for the first one that matches.
2434 return linear_search(methods, name);
2435 }
2436
2437 int len = methods->length();
2438 int l = 0;
2439 int h = len - 1;
2440
2441 // methods are sorted by ascending addresses of their names, so do binary search
2442 while (l <= h) {
2443 int mid = (l + h) >> 1;
2444 Method* m = methods->at(mid);
2445 assert(m->is_method(), "must be method");
2446 int res = m->name()->fast_compare(name);
2447 if (res == 0) {
2448 return mid;
2449 } else if (res < 0) {
2450 l = mid + 1;
2451 } else {
2452 h = mid - 1;
2453 }
2454 }
2455 return -1;
2456 }
2457
2458 // find_method looks up the name/signature in the local methods array
2459 Method* InstanceKlass::find_method(const Symbol* name,
2460 const Symbol* signature) const {
2461 return find_method_impl(name, signature,
2462 OverpassLookupMode::find,
2463 StaticLookupMode::find,
2464 PrivateLookupMode::find);
2465 }
2466
2467 Method* InstanceKlass::find_method_impl(const Symbol* name,
2468 const Symbol* signature,
2469 OverpassLookupMode overpass_mode,
2470 StaticLookupMode static_mode,
2471 PrivateLookupMode private_mode) const {
2472 return InstanceKlass::find_method_impl(methods(),
2473 name,
2474 signature,
2475 overpass_mode,
2476 static_mode,
2477 private_mode);
2478 }
2479
2480 // find_instance_method looks up the name/signature in the local methods array
2481 // and skips over static methods
2482 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2483 const Symbol* name,
2484 const Symbol* signature,
2485 PrivateLookupMode private_mode) {
2486 Method* const meth = InstanceKlass::find_method_impl(methods,
2487 name,
2488 signature,
2489 OverpassLookupMode::find,
2490 StaticLookupMode::skip,
2491 private_mode);
2492 assert(((meth == nullptr) || !meth->is_static()),
2493 "find_instance_method should have skipped statics");
2494 return meth;
2495 }
2496
2497 // find_instance_method looks up the name/signature in the local methods array
2498 // and skips over static methods
2499 Method* InstanceKlass::find_instance_method(const Symbol* name,
2500 const Symbol* signature,
2501 PrivateLookupMode private_mode) const {
2502 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2503 }
2504
2505 // Find looks up the name/signature in the local methods array
2506 // and filters on the overpass, static and private flags
2507 // This returns the first one found
2508 // note that the local methods array can have up to one overpass, one static
2509 // and one instance (private or not) with the same name/signature
2510 Method* InstanceKlass::find_local_method(const Symbol* name,
2511 const Symbol* signature,
2512 OverpassLookupMode overpass_mode,
2513 StaticLookupMode static_mode,
2514 PrivateLookupMode private_mode) const {
2515 return InstanceKlass::find_method_impl(methods(),
2516 name,
2517 signature,
2518 overpass_mode,
2519 static_mode,
2520 private_mode);
2521 }
2522
2523 // Find looks up the name/signature in the local methods array
2524 // and filters on the overpass, static and private flags
2525 // This returns the first one found
2526 // note that the local methods array can have up to one overpass, one static
2527 // and one instance (private or not) with the same name/signature
2528 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2529 const Symbol* name,
2530 const Symbol* signature,
2531 OverpassLookupMode overpass_mode,
2532 StaticLookupMode static_mode,
2533 PrivateLookupMode private_mode) {
2534 return InstanceKlass::find_method_impl(methods,
2535 name,
2536 signature,
2537 overpass_mode,
2538 static_mode,
2539 private_mode);
2540 }
2541
2542 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2543 const Symbol* name,
2544 const Symbol* signature) {
2545 return InstanceKlass::find_method_impl(methods,
2546 name,
2547 signature,
2548 OverpassLookupMode::find,
2549 StaticLookupMode::find,
2550 PrivateLookupMode::find);
2551 }
2552
2553 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2554 const Symbol* name,
2555 const Symbol* signature,
2556 OverpassLookupMode overpass_mode,
2557 StaticLookupMode static_mode,
2558 PrivateLookupMode private_mode) {
2559 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2560 return hit >= 0 ? methods->at(hit): nullptr;
2561 }
2562
2563 // true if method matches signature and conforms to skipping_X conditions.
2564 static bool method_matches(const Method* m,
2565 const Symbol* signature,
2566 bool skipping_overpass,
2567 bool skipping_static,
2568 bool skipping_private) {
2569 return ((m->signature() == signature) &&
2570 (!skipping_overpass || !m->is_overpass()) &&
2571 (!skipping_static || !m->is_static()) &&
2572 (!skipping_private || !m->is_private()));
2573 }
2574
2575 // Used directly for default_methods to find the index into the
2576 // default_vtable_indices, and indirectly by find_method
2577 // find_method_index looks in the local methods array to return the index
2578 // of the matching name/signature. If, overpass methods are being ignored,
2579 // the search continues to find a potential non-overpass match. This capability
2580 // is important during method resolution to prefer a static method, for example,
2581 // over an overpass method.
2582 // There is the possibility in any _method's array to have the same name/signature
2583 // for a static method, an overpass method and a local instance method
2584 // To correctly catch a given method, the search criteria may need
2585 // to explicitly skip the other two. For local instance methods, it
2586 // is often necessary to skip private methods
2587 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2588 const Symbol* name,
2589 const Symbol* signature,
2590 OverpassLookupMode overpass_mode,
2591 StaticLookupMode static_mode,
2592 PrivateLookupMode private_mode) {
2593 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2594 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2595 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2596 const int hit = quick_search(methods, name);
2597 if (hit != -1) {
2598 const Method* const m = methods->at(hit);
2599
2600 // Do linear search to find matching signature. First, quick check
2601 // for common case, ignoring overpasses if requested.
2602 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2603 return hit;
2604 }
2605
2606 // search downwards through overloaded methods
2607 int i;
2608 for (i = hit - 1; i >= 0; --i) {
2609 const Method* const m = methods->at(i);
2610 assert(m->is_method(), "must be method");
2611 if (m->name() != name) {
2612 break;
2613 }
2614 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2615 return i;
2616 }
2617 }
2618 // search upwards
2619 for (i = hit + 1; i < methods->length(); ++i) {
2620 const Method* const m = methods->at(i);
2621 assert(m->is_method(), "must be method");
2622 if (m->name() != name) {
2623 break;
2624 }
2625 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2626 return i;
2627 }
2628 }
2629 // not found
2630 #ifdef ASSERT
2631 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2632 linear_search(methods, name, signature);
2633 assert(-1 == index, "binary search should have found entry %d", index);
2634 #endif
2635 }
2636 return -1;
2637 }
2638
2639 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2640 return find_method_by_name(methods(), name, end);
2641 }
2642
2643 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2644 const Symbol* name,
2645 int* end_ptr) {
2646 assert(end_ptr != nullptr, "just checking");
2647 int start = quick_search(methods, name);
2648 int end = start + 1;
2649 if (start != -1) {
2650 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2651 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2652 *end_ptr = end;
2653 return start;
2654 }
2655 return -1;
2656 }
2657
2658 // uncached_lookup_method searches both the local class methods array and all
2659 // superclasses methods arrays, skipping any overpass methods in superclasses,
2660 // and possibly skipping private methods.
2661 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2662 const Symbol* signature,
2663 OverpassLookupMode overpass_mode,
2664 PrivateLookupMode private_mode) const {
2665 OverpassLookupMode overpass_local_mode = overpass_mode;
2666 const InstanceKlass* klass = this;
2667 while (klass != nullptr) {
2668 Method* const method = klass->find_method_impl(name,
2669 signature,
2670 overpass_local_mode,
2671 StaticLookupMode::find,
2672 private_mode);
2673 if (method != nullptr) {
2674 return method;
2675 }
2676 if (name == vmSymbols::object_initializer_name()) {
2677 break; // <init> is never inherited
2678 }
2679 klass = klass->super();
2680 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2681 }
2682 return nullptr;
2683 }
2684
2685 #ifdef ASSERT
2686 // search through class hierarchy and return true if this class or
2687 // one of the superclasses was redefined
2688 bool InstanceKlass::has_redefined_this_or_super() const {
2689 const InstanceKlass* klass = this;
2690 while (klass != nullptr) {
2691 if (klass->has_been_redefined()) {
2692 return true;
2693 }
2694 klass = klass->super();
2695 }
2696 return false;
2697 }
2698 #endif
2699
2700 // lookup a method in the default methods list then in all transitive interfaces
2701 // Do NOT return private or static methods
2702 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2703 Symbol* signature) const {
2704 Method* m = nullptr;
2705 if (default_methods() != nullptr) {
2706 m = find_method(default_methods(), name, signature);
2707 }
2708 // Look up interfaces
2709 if (m == nullptr) {
2710 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2711 }
2712 return m;
2713 }
2714
2715 // lookup a method in all the interfaces that this class implements
2716 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2717 // They should only be found in the initial InterfaceMethodRef
2718 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2719 Symbol* signature,
2720 DefaultsLookupMode defaults_mode) const {
2721 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2722 int num_ifs = all_ifs->length();
2723 InstanceKlass *ik = nullptr;
2724 for (int i = 0; i < num_ifs; i++) {
2725 ik = all_ifs->at(i);
2726 Method* m = ik->lookup_method(name, signature);
2727 if (m != nullptr && m->is_public() && !m->is_static() &&
2728 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2729 return m;
2730 }
2731 }
2732 return nullptr;
2733 }
2734
2735 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2736 :_st(st), _verbose(verbose) {
2737 ResourceMark rm;
2738 _st->print("%-18s ", "KlassAddr");
2739 _st->print("%-4s ", "Size");
2740 _st->print("%-20s ", "State");
2741 _st->print("%-7s ", "Flags");
2742 _st->print("%-5s ", "ClassName");
2743 _st->cr();
2744 }
2745
2746 void PrintClassClosure::do_klass(Klass* k) {
2747 ResourceMark rm;
2748 // klass pointer
2749 _st->print(PTR_FORMAT " ", p2i(k));
2750 // klass size
2751 _st->print("%4d ", k->size());
2752 // initialization state
2753 if (k->is_instance_klass()) {
2754 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2755 } else {
2756 _st->print("%-20s ","");
2757 }
2758 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2759 char buf[10];
2760 int i = 0;
2761 if (k->has_finalizer()) buf[i++] = 'F';
2762 if (k->is_instance_klass()) {
2763 InstanceKlass* ik = InstanceKlass::cast(k);
2764 if (ik->has_final_method()) buf[i++] = 'f';
2765 if (ik->is_rewritten()) buf[i++] = 'W';
2766 if (ik->is_contended()) buf[i++] = 'C';
2767 if (ik->has_been_redefined()) buf[i++] = 'R';
2768 if (ik->in_aot_cache()) buf[i++] = 'S';
2769 }
2770 buf[i++] = '\0';
2771 _st->print("%-7s ", buf);
2772 // klass name
2773 _st->print("%-5s ", k->external_name());
2774 // end
2775 _st->cr();
2776 if (_verbose) {
2777 k->print_on(_st);
2778 }
2779 }
2780
2781 /* jni_id_for for jfieldIds only */
2782 JNIid* InstanceKlass::jni_id_for(int offset) {
2783 MutexLocker ml(JfieldIdCreation_lock);
2784 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2785 if (probe == nullptr) {
2786 // Allocate new static field identifier
2787 probe = new JNIid(this, offset, jni_ids());
2788 set_jni_ids(probe);
2789 }
2790 return probe;
2791 }
2792
2793 u2 InstanceKlass::enclosing_method_data(int offset) const {
2794 const Array<jushort>* const inner_class_list = inner_classes();
2795 if (inner_class_list == nullptr) {
2796 return 0;
2797 }
2798 const int length = inner_class_list->length();
2799 if (length % inner_class_next_offset == 0) {
2800 return 0;
2801 }
2802 const int index = length - enclosing_method_attribute_size;
2803 assert(offset < enclosing_method_attribute_size, "invalid offset");
2804 return inner_class_list->at(index + offset);
2805 }
2806
2807 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2808 u2 method_index) {
2809 Array<jushort>* inner_class_list = inner_classes();
2810 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2811 int length = inner_class_list->length();
2812 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2813 int index = length - enclosing_method_attribute_size;
2814 inner_class_list->at_put(
2815 index + enclosing_method_class_index_offset, class_index);
2816 inner_class_list->at_put(
2817 index + enclosing_method_method_index_offset, method_index);
2818 }
2819 }
2820
2821 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2822 if (method->is_old() && !method->is_obsolete()) {
2823 // If the method passed in is old (but not obsolete), use the current version.
2824 method = method_with_idnum((int)idnum);
2825 assert(method != nullptr, "old and but not obsolete, so should exist");
2826 }
2827 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2828 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2829 return new_id;
2830 }
2831
2832 // Allocate the jmethodID cache.
2833 static jmethodID* create_jmethod_id_cache(size_t size) {
2834 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2835 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2836 // cache size is stored in element[0], other elements offset by one
2837 jmeths[0] = (jmethodID)size;
2838 return jmeths;
2839 }
2840
2841 // When reading outside a lock, use this.
2842 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2843 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2844 }
2845
2846 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2847 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2848 }
2849
2850 // Lookup or create a jmethodID.
2851 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2852 int idnum = method->method_idnum();
2853 jmethodID* jmeths = methods_jmethod_ids_acquire();
2854
2855 // We use a double-check locking idiom here because this cache is
2856 // performance sensitive. In the normal system, this cache only
2857 // transitions from null to non-null which is safe because we use
2858 // release_set_methods_jmethod_ids() to advertise the new cache.
2859 // A partially constructed cache should never be seen by a racing
2860 // thread. We also use release_store() to save a new jmethodID
2861 // in the cache so a partially constructed jmethodID should never be
2862 // seen either. Cache reads of existing jmethodIDs proceed without a
2863 // lock, but cache writes of a new jmethodID requires uniqueness and
2864 // creation of the cache itself requires no leaks so a lock is
2865 // acquired in those two cases.
2866 //
2867 // If the RedefineClasses() API has been used, then this cache grows
2868 // in the redefinition safepoint.
2869
2870 if (jmeths == nullptr) {
2871 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2872 jmeths = _methods_jmethod_ids;
2873 // Still null?
2874 if (jmeths == nullptr) {
2875 size_t size = idnum_allocated_count();
2876 assert(size > (size_t)idnum, "should already have space");
2877 jmeths = create_jmethod_id_cache(size);
2878 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2879
2880 // publish jmeths
2881 release_set_methods_jmethod_ids(jmeths);
2882 return new_id;
2883 }
2884 }
2885
2886 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2887 if (id == nullptr) {
2888 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2889 id = jmeths[idnum + 1];
2890 // Still null?
2891 if (id == nullptr) {
2892 return update_jmethod_id(jmeths, method, idnum);
2893 }
2894 }
2895 return id;
2896 }
2897
2898 void InstanceKlass::update_methods_jmethod_cache() {
2899 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2900 jmethodID* cache = _methods_jmethod_ids;
2901 if (cache != nullptr) {
2902 size_t size = idnum_allocated_count();
2903 size_t old_size = (size_t)cache[0];
2904 if (old_size < size + 1) {
2905 // Allocate a larger one and copy entries to the new one.
2906 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2907 jmethodID* new_cache = create_jmethod_id_cache(size);
2908
2909 for (int i = 1; i <= (int)old_size; i++) {
2910 new_cache[i] = cache[i];
2911 }
2912 _methods_jmethod_ids = new_cache;
2913 FREE_C_HEAP_ARRAY(cache);
2914 }
2915 }
2916 }
2917
2918 // Make a jmethodID for all methods in this class. This makes getting all method
2919 // ids much, much faster with classes with more than 8
2920 // methods, and has a *substantial* effect on performance with jvmti
2921 // code that loads all jmethodIDs for all classes.
2922 void InstanceKlass::make_methods_jmethod_ids() {
2923 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2924 jmethodID* jmeths = _methods_jmethod_ids;
2925 if (jmeths == nullptr) {
2926 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2927 release_set_methods_jmethod_ids(jmeths);
2928 }
2929
2930 int length = methods()->length();
2931 for (int index = 0; index < length; index++) {
2932 Method* m = methods()->at(index);
2933 int idnum = m->method_idnum();
2934 assert(!m->is_old(), "should not have old methods or I'm confused");
2935 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2936 if (!m->is_overpass() && // skip overpasses
2937 id == nullptr) {
2938 id = Method::make_jmethod_id(class_loader_data(), m);
2939 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2940 }
2941 }
2942 }
2943
2944 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2945 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2946 int idnum = method->method_idnum();
2947 jmethodID* jmeths = methods_jmethod_ids_acquire();
2948 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2949 }
2950
2951 inline DependencyContext InstanceKlass::dependencies() {
2952 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2953 return dep_context;
2954 }
2955
2956 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2957 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2958 }
2959
2960 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2961 assert_lock_strong(CodeCache_lock);
2962 dependencies().add_dependent_nmethod(nm);
2963 }
2964
2965 void InstanceKlass::clean_dependency_context() {
2966 dependencies().clean_unloading_dependents();
2967 }
2968
2969 #ifndef PRODUCT
2970 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2971 dependencies().print_dependent_nmethods(verbose);
2972 }
2973
2974 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2975 return dependencies().is_dependent_nmethod(nm);
2976 }
2977 #endif //PRODUCT
2978
2979 void InstanceKlass::clean_weak_instanceklass_links() {
2980 clean_implementors_list();
2981 clean_method_data();
2982 }
2983
2984 void InstanceKlass::clean_implementors_list() {
2985 assert(is_loader_alive(), "this klass should be live");
2986 if (is_interface()) {
2987 assert (ClassUnloading, "only called for ClassUnloading");
2988 for (;;) {
2989 // Use load_acquire due to competing with inserts
2990 InstanceKlass* volatile* iklass = adr_implementor();
2991 assert(iklass != nullptr, "Klass must not be null");
2992 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2993 if (impl != nullptr && !impl->is_loader_alive()) {
2994 // null this field, might be an unloaded instance klass or null
2995 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2996 // Successfully unlinking implementor.
2997 if (log_is_enabled(Trace, class, unload)) {
2998 ResourceMark rm;
2999 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
3000 }
3001 return;
3002 }
3003 } else {
3004 return;
3005 }
3006 }
3007 }
3008 }
3009
3010 void InstanceKlass::clean_method_data() {
3011 for (int m = 0; m < methods()->length(); m++) {
3012 MethodData* mdo = methods()->at(m)->method_data();
3013 if (mdo != nullptr) {
3014 mdo->clean_method_data(/*always_clean*/false);
3015 }
3016 }
3017 }
3018
3019 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
3020 Klass::metaspace_pointers_do(it);
3021
3022 if (log_is_enabled(Trace, aot)) {
3023 ResourceMark rm;
3024 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
3025 }
3026
3027 it->push(&_annotations);
3028 it->push((Klass**)&_array_klasses);
3029 if (!is_rewritten()) {
3030 it->push(&_constants, MetaspaceClosure::_writable);
3031 } else {
3032 it->push(&_constants);
3033 }
3034 it->push(&_inner_classes);
3035 #if INCLUDE_JVMTI
3036 it->push(&_previous_versions);
3037 #endif
3038 #if INCLUDE_CDS
3039 // For "old" classes with methods containing the jsr bytecode, the _methods array will
3040 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
3041 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
3042 // The length check on the _methods is necessary because classes which don't have any
3043 // methods share the Universe::_the_empty_method_array which is in the RO region.
3044 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
3045 // To handle jsr bytecode, new Method* maybe stored into _methods
3046 it->push(&_methods, MetaspaceClosure::_writable);
3047 } else {
3048 #endif
3049 it->push(&_methods);
3050 #if INCLUDE_CDS
3051 }
3052 #endif
3053 it->push(&_default_methods);
3054 it->push(&_local_interfaces);
3055 it->push(&_transitive_interfaces);
3056 it->push(&_method_ordering);
3057 if (!is_rewritten()) {
3058 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
3059 } else {
3060 it->push(&_default_vtable_indices);
3061 }
3062
3063 it->push(&_fieldinfo_stream);
3064 it->push(&_fieldinfo_search_table);
3065 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
3066 it->push(&_fields_status, MetaspaceClosure::_writable);
3067
3068 if (itable_length() > 0) {
3069 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
3070 int method_table_offset_in_words = ioe->offset()/wordSize;
3071 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
3072
3073 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
3074 / itableOffsetEntry::size();
3075
3076 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
3077 if (ioe->interface_klass() != nullptr) {
3078 it->push(ioe->interface_klass_addr());
3079 itableMethodEntry* ime = ioe->first_method_entry(this);
3080 int n = klassItable::method_count_for_interface(ioe->interface_klass());
3081 for (int index = 0; index < n; index ++) {
3082 it->push(ime[index].method_addr());
3083 }
3084 }
3085 }
3086 }
3087
3088 it->push(&_nest_host);
3089 it->push(&_nest_members);
3090 it->push(&_permitted_subclasses);
3091 it->push(&_loadable_descriptors);
3092 it->push(&_acmp_maps_array, MetaspaceClosure::_writable);
3093 it->push(&_record_components);
3094 it->push(&_value_field_info_array, MetaspaceClosure::_writable);
3095
3096 if (CDSConfig::is_dumping_full_module_graph() && !defined_by_other_loaders()) {
3097 it->push(&_package_entry);
3098 }
3099 }
3100
3101 #if INCLUDE_CDS
3102 void InstanceKlass::remove_unshareable_info() {
3103
3104 if (is_linked()) {
3105 assert(can_be_verified_at_dumptime(), "must be");
3106 // Remember this so we can avoid walking the hierarchy at runtime.
3107 set_verified_at_dump_time();
3108 }
3109
3110 _misc_flags.set_has_init_deps_processed(false);
3111
3112 Klass::remove_unshareable_info();
3113
3114 if (SystemDictionaryShared::has_class_failed_verification(this)) {
3115 // Classes are attempted to link during dumping and may fail,
3116 // but these classes are still in the dictionary and class list in CLD.
3117 // If the class has failed verification, there is nothing else to remove.
3118 return;
3119 }
3120
3121 // Reset to the 'allocated' state to prevent any premature accessing to
3122 // a shared class at runtime while the class is still being loaded and
3123 // restored. A class' init_state is set to 'loaded' at runtime when it's
3124 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
3125 _init_state = allocated;
3126
3127 // Classes without an AOT-initialized mirror will run <clinit> again. Restore
3128 // the initial status of their strict static fields for that execution.
3129 if (has_strict_static_fields() && !has_aot_initialized_mirror()) {
3130 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
3131 FieldInfo fi = fs.to_FieldInfo();
3132 if (fi.access_flags().is_strict() && fi.access_flags().is_static() && fi.initializer_index() == 0) {
3133 FieldStatus& fs = *fields_status()->adr_at(fi.index());
3134 fs.update_strict_static_unset(true);
3135 fs.update_strict_static_unread(true);
3136 }
3137 }
3138 }
3139
3140 { // Otherwise this needs to take out the Compile_lock.
3141 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3142 init_implementor();
3143 }
3144
3145 // Call remove_unshareable_info() on other objects that belong to this class, except
3146 // for constants()->remove_unshareable_info(), which is called in a separate pass in
3147 // ArchiveBuilder::make_klasses_shareable(),
3148
3149 for (int i = 0; i < methods()->length(); i++) {
3150 Method* m = methods()->at(i);
3151 m->remove_unshareable_info();
3152 }
3153
3154 // do array classes also.
3155 if (array_klasses() != nullptr) {
3156 array_klasses()->remove_unshareable_info();
3157 }
3158
3159 // These are not allocated from metaspace. They are safe to set to nullptr.
3160 _source_debug_extension = nullptr;
3161 _dep_context = nullptr;
3162 _osr_nmethods_head = nullptr;
3163 #if INCLUDE_JVMTI
3164 _breakpoints = nullptr;
3165 _previous_versions = nullptr;
3166 _cached_class_file = nullptr;
3167 _jvmti_cached_class_field_map = nullptr;
3168 #endif
3169
3170 _init_thread = nullptr;
3171 _methods_jmethod_ids = nullptr;
3172 _jni_ids = nullptr;
3173 _oop_map_cache = nullptr;
3174 if (CDSConfig::is_dumping_method_handles() && AOTHeap::is_lambda_proxy_klass(this)) {
3175 // keep _nest_host
3176 } else {
3177 // clear _nest_host to ensure re-load at runtime
3178 _nest_host = nullptr;
3179 }
3180 init_shared_package_entry();
3181 _dep_context_last_cleaned = 0;
3182 DEBUG_ONLY(_shared_class_load_count = 0);
3183
3184 remove_unshareable_flags();
3185
3186 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
3187 }
3188
3189 void InstanceKlass::remove_unshareable_flags() {
3190 // clear all the flags/stats that shouldn't be in the archived version
3191 assert(!is_scratch_class(), "must be");
3192 assert(!has_been_redefined(), "must be");
3193 #if INCLUDE_JVMTI
3194 set_is_being_redefined(false);
3195 #endif
3196 set_has_resolved_methods(false);
3197 }
3198
3199 void InstanceKlass::remove_java_mirror() {
3200 Klass::remove_java_mirror();
3201
3202 // do array classes also.
3203 if (array_klasses() != nullptr) {
3204 array_klasses()->remove_java_mirror();
3205 }
3206 }
3207
3208 void InstanceKlass::init_shared_package_entry() {
3209 assert(CDSConfig::is_dumping_archive(), "must be");
3210 if (!CDSConfig::is_dumping_full_module_graph() || defined_by_other_loaders()) {
3211 _package_entry = nullptr;
3212 }
3213 }
3214
3215 void InstanceKlass::compute_has_loops_flag_for_methods() {
3216 Array<Method*>* methods = this->methods();
3217 for (int index = 0; index < methods->length(); ++index) {
3218 Method* m = methods->at(index);
3219 if (!m->is_overpass()) { // work around JDK-8305771
3220 m->compute_has_loops_flag();
3221 }
3222 }
3223 }
3224
3225 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
3226 PackageEntry* pkg_entry, TRAPS) {
3227 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
3228 // before the InstanceKlass is added to the SystemDictionary. Make
3229 // sure the current state is <loaded.
3230 assert(!is_loaded(), "invalid init state");
3231 assert(!shared_loading_failed(), "Must not try to load failed class again");
3232 set_package(loader_data, pkg_entry, CHECK);
3233 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
3234
3235 if (is_value_klass()) {
3236 ValueKlass::cast(this)->initialize_calling_convention(CHECK);
3237 }
3238
3239 Array<Method*>* methods = this->methods();
3240 int num_methods = methods->length();
3241 for (int index = 0; index < num_methods; ++index) {
3242 methods->at(index)->restore_unshareable_info(CHECK);
3243 }
3244 #if INCLUDE_JVMTI
3245 if (JvmtiExport::has_redefined_a_class()) {
3246 // Reinitialize vtable because RedefineClasses may have changed some
3247 // entries in this vtable for super classes so the CDS vtable might
3248 // point to old or obsolete entries. RedefineClasses doesn't fix up
3249 // vtables in the shared system dictionary, only the main one.
3250 // It also redefines the itable too so fix that too.
3251 // First fix any default methods that point to a super class that may
3252 // have been redefined.
3253 bool trace_name_printed = false;
3254 adjust_default_methods(&trace_name_printed);
3255 if (verified_at_dump_time()) {
3256 // Initialize vtable and itable for classes which can be verified at dump time.
3257 // Unlinked classes such as old classes with major version < 50 cannot be verified
3258 // at dump time.
3259 vtable().initialize_vtable();
3260 itable().initialize_itable();
3261 }
3262 }
3263 #endif // INCLUDE_JVMTI
3264
3265 // restore constant pool resolved references
3266 constants()->restore_unshareable_info(CHECK);
3267
3268 // Restore acmp_maps java array from the version stored in metadata.
3269 // if it cannot be found in the archive
3270 if (Arguments::is_valhalla_enabled() && has_acmp_maps_offset() && java_mirror()->obj_field(_acmp_maps_offset) == nullptr) {
3271 int acmp_maps_size = _acmp_maps_array->length();
3272 typeArrayOop map = oopFactory::new_intArray(acmp_maps_size, CHECK);
3273 typeArrayHandle map_h(THREAD, map);
3274 for (int i = 0; i < acmp_maps_size; i++) {
3275 map_h->int_at_put(i, _acmp_maps_array->at(i));
3276 }
3277 java_mirror()->obj_field_put(_acmp_maps_offset, map_h());
3278 }
3279
3280 if (array_klasses() != nullptr) {
3281 // To get a consistent list of classes we need MultiArray_lock to ensure
3282 // array classes aren't observed while they are being restored.
3283 RecursiveLocker rl(MultiArray_lock, THREAD);
3284 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
3285 // Array classes have null protection domain.
3286 // --> see ArrayKlass::complete_create_array_klass()
3287 if (class_loader_data() == nullptr) {
3288 ResourceMark rm(THREAD);
3289 log_debug(cds)(" loader_data %s ", loader_data == nullptr ? "nullptr" : "non null");
3290 log_debug(cds)(" this %s array_klasses %s ", this->name()->as_C_string(), array_klasses()->name()->as_C_string());
3291 }
3292 assert(!array_klasses()->is_refined_objArray_klass(), "must be non-refined objarrayklass");
3293 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3294 }
3295
3296 // Initialize @ValueBased class annotation if not already set in the archived klass.
3297 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
3298 set_is_value_based();
3299 }
3300
3301 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
3302 }
3303
3304 bool InstanceKlass::can_be_verified_at_dumptime() const {
3305 if (CDSConfig::is_dumping_dynamic_archive() && AOTMetaspace::in_aot_cache(this)) {
3306 // This is a class that was dumped into the base archive, so we know
3307 // it was verified at dump time.
3308 return true;
3309 }
3310
3311 if (CDSConfig::is_preserving_verification_constraints()) {
3312 return true;
3313 }
3314
3315 if (CDSConfig::is_old_class_for_verifier(this)) {
3316 // The old verifier does not save verification constraints, so at run time
3317 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
3318 return false;
3319 }
3320
3321 if (CDSConfig::is_dumping_final_static_archive() && fail_over_verified()) {
3322 // This is a class with version >50 but was verified with the old verifier in the training run,
3323 // which had -XX:+AOTClassLinking. However, we are now in the assembly run with -XX:-AOTClassLinking.
3324 // As SystemDictionaryShared::check_verification_constraints() does not support this case,
3325 // we must exclude this class.
3326 assert(!CDSConfig::is_dumping_aot_linked_classes(), "must be");
3327 return false;
3328 }
3329
3330 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
3331 return false;
3332 }
3333 Array<InstanceKlass*>* interfaces = local_interfaces();
3334 int len = interfaces->length();
3335 for (int i = 0; i < len; i++) {
3336 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3337 return false;
3338 }
3339 }
3340 return true;
3341 }
3342
3343 #endif // INCLUDE_CDS
3344
3345 #if INCLUDE_JVMTI
3346 static void clear_all_breakpoints(Method* m) {
3347 m->clear_all_breakpoints();
3348 }
3349 #endif
3350
3351 void InstanceKlass::unload_class(InstanceKlass* ik) {
3352
3353 if (ik->is_scratch_class()) {
3354 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
3355 return;
3356 }
3357 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
3358
3359 // Release dependencies.
3360 ik->dependencies().remove_all_dependents();
3361
3362 // notify the debugger
3363 if (JvmtiExport::should_post_class_unload()) {
3364 JvmtiExport::post_class_unload(ik);
3365 }
3366
3367 // notify ClassLoadingService of class unload
3368 ClassLoadingService::notify_class_unloaded(ik);
3369
3370 SystemDictionaryShared::handle_class_unloading(ik);
3371
3372 if (log_is_enabled(Info, class, unload)) {
3373 ResourceMark rm;
3374 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3375 }
3376
3377 Thread* const current = Thread::current();
3378 Events::log_class_unloading(current, ik);
3379
3380 #if INCLUDE_JFR
3381 assert(ik != nullptr, "invariant");
3382 // For concurrent unloading, we need the ik, the cld, and the event
3383 // to end up in the correct JFR epoch, hence the acquisition of the
3384 // epoch shift lock before the event.commit().
3385 if (EventClassUnload::is_enabled()) {
3386 EventClassUnload event;
3387 event.set_unloadedClass(ik);
3388 event.set_definingClassLoader(ik->class_loader_data());
3389 ConditionalMutexLocker ml(JfrEpochShift_lock, UseShenandoahGC || UseZGC, Mutex::_no_safepoint_check_flag);
3390 event.commit();
3391 }
3392 #endif
3393 }
3394
3395 static void method_release_C_heap_structures(Method* m) {
3396 m->release_C_heap_structures();
3397 }
3398
3399 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3400 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3401 // Clean up C heap
3402 Klass::release_C_heap_structures();
3403
3404 // Deallocate and call destructors for MDO mutexes
3405 if (release_sub_metadata) {
3406 methods_do(method_release_C_heap_structures);
3407 }
3408
3409 // Deallocate oop map cache
3410 if (_oop_map_cache != nullptr) {
3411 delete _oop_map_cache;
3412 _oop_map_cache = nullptr;
3413 }
3414
3415 // Deallocate JNI identifiers for jfieldIDs
3416 JNIid::deallocate(jni_ids());
3417 set_jni_ids(nullptr);
3418
3419 jmethodID* jmeths = _methods_jmethod_ids;
3420 if (jmeths != nullptr) {
3421 release_set_methods_jmethod_ids(nullptr);
3422 FreeHeap(jmeths);
3423 }
3424
3425 assert(_dep_context == nullptr,
3426 "dependencies should already be cleaned");
3427
3428 #if INCLUDE_JVMTI
3429 // Deallocate breakpoint records
3430 if (breakpoints() != nullptr) {
3431 methods_do(clear_all_breakpoints);
3432 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3433 }
3434
3435 // deallocate the cached class file
3436 if (_cached_class_file != nullptr) {
3437 os::free(_cached_class_file);
3438 _cached_class_file = nullptr;
3439 }
3440 #endif
3441
3442 FREE_C_HEAP_ARRAY(_source_debug_extension);
3443
3444 if (release_sub_metadata) {
3445 constants()->release_C_heap_structures();
3446 }
3447 }
3448
3449 // The constant pool is on stack if any of the methods are executing or
3450 // referenced by handles.
3451 bool InstanceKlass::on_stack() const {
3452 return _constants->on_stack();
3453 }
3454
3455 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3456 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3457 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3458
3459 Symbol* InstanceKlass::source_file_name(int version) const {
3460 // Return the source file name for this version of the classfile, if redefined with RedefineClasses
3461 const InstanceKlass* holder = get_klass_version(version);
3462 if (holder == nullptr) {
3463 // Redefined previous class has been cleaned up.
3464 return nullptr;
3465 } else {
3466 return holder->source_file_name();
3467 }
3468 }
3469
3470 // minor and major version numbers of class file
3471 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3472 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3473 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3474 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3475
3476 bool InstanceKlass::supports_value_types() const {
3477 return major_version() >= Verifier::VALUE_TYPES_MAJOR_VERSION && minor_version() == Verifier::JAVA_PREVIEW_MINOR_VERSION;
3478 }
3479
3480 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3481 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3482 if (ik->constants()->version() == version) {
3483 return ik;
3484 }
3485 }
3486 return nullptr;
3487 }
3488
3489 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3490 if (array == nullptr) {
3491 _source_debug_extension = nullptr;
3492 } else {
3493 // Adding one to the attribute length in order to store a null terminator
3494 // character could cause an overflow because the attribute length is
3495 // already coded with an u4 in the classfile, but in practice, it's
3496 // unlikely to happen.
3497 assert((length+1) > length, "Overflow checking");
3498 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3499 for (int i = 0; i < length; i++) {
3500 sde[i] = array[i];
3501 }
3502 sde[length] = '\0';
3503 _source_debug_extension = sde;
3504 }
3505 }
3506
3507 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3508 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3509 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3510
3511 const char* InstanceKlass::signature_name() const {
3512 // Get the internal name as a c string
3513 const char* src = (const char*) (name()->as_C_string());
3514 const int src_length = (int)strlen(src);
3515
3516 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3517
3518 // Add L as type indicator
3519 int dest_index = 0;
3520 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3521
3522 // Add the actual class name
3523 for (int src_index = 0; src_index < src_length; ) {
3524 dest[dest_index++] = src[src_index++];
3525 }
3526
3527 if (is_hidden()) { // Replace the last '+' with a '.'.
3528 for (int index = (int)src_length; index > 0; index--) {
3529 if (dest[index] == '+') {
3530 dest[index] = JVM_SIGNATURE_DOT;
3531 break;
3532 }
3533 }
3534 }
3535
3536 // Add the semicolon and the null
3537 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3538 dest[dest_index] = '\0';
3539 return dest;
3540 }
3541
3542 ModuleEntry* InstanceKlass::module() const {
3543 if (is_hidden() &&
3544 in_unnamed_package() &&
3545 class_loader_data()->has_class_mirror_holder()) {
3546 // For a non-strong hidden class defined to an unnamed package,
3547 // its (class held) CLD will not have an unnamed module created for it.
3548 // Two choices to find the correct ModuleEntry:
3549 // 1. If hidden class is within a nest, use nest host's module
3550 // 2. Find the unnamed module off from the class loader
3551 // For now option #2 is used since a nest host is not set until
3552 // after the instance class is created in jvm_lookup_define_class().
3553 if (class_loader_data()->is_boot_class_loader_data()) {
3554 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3555 } else {
3556 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3557 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3558 return java_lang_Module::module_entry(module);
3559 }
3560 }
3561
3562 // Class is in a named package
3563 if (!in_unnamed_package()) {
3564 return _package_entry->module();
3565 }
3566
3567 // Class is in an unnamed package, return its loader's unnamed module
3568 return class_loader_data()->unnamed_module();
3569 }
3570
3571 bool InstanceKlass::in_javabase_module() const {
3572 return module()->name() == vmSymbols::java_base();
3573 }
3574
3575 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3576
3577 // ensure java/ packages only loaded by boot or platform builtin loaders
3578 // not needed for shared class since CDS does not archive prohibited classes.
3579 if (!in_aot_cache()) {
3580 check_prohibited_package(name(), loader_data, CHECK);
3581 }
3582
3583 if (in_aot_cache() && _package_entry != nullptr) {
3584 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3585 // we can use the saved package
3586 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3587 return;
3588 } else {
3589 _package_entry = nullptr;
3590 }
3591 }
3592
3593 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3594 // it returns, so we need to decrement it when the current function exits.
3595 TempNewSymbol from_class_name =
3596 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3597
3598 Symbol* pkg_name;
3599 if (pkg_entry != nullptr) {
3600 pkg_name = pkg_entry->name();
3601 } else {
3602 pkg_name = from_class_name;
3603 }
3604
3605 if (pkg_name != nullptr && loader_data != nullptr) {
3606
3607 // Find in class loader's package entry table.
3608 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3609
3610 // If the package name is not found in the loader's package
3611 // entry table, it is an indication that the package has not
3612 // been defined. Consider it defined within the unnamed module.
3613 if (_package_entry == nullptr) {
3614
3615 if (!ModuleEntryTable::javabase_defined()) {
3616 // Before java.base is defined during bootstrapping, define all packages in
3617 // the java.base module. If a non-java.base package is erroneously placed
3618 // in the java.base module it will be caught later when java.base
3619 // is defined by ModuleEntryTable::verify_javabase_packages check.
3620 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3621 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3622 } else {
3623 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3624 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3625 }
3626
3627 // A package should have been successfully created
3628 DEBUG_ONLY(ResourceMark rm(THREAD));
3629 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3630 name()->as_C_string(), loader_data->loader_name_and_id());
3631 }
3632
3633 if (log_is_enabled(Debug, module)) {
3634 ResourceMark rm(THREAD);
3635 ModuleEntry* m = _package_entry->module();
3636 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3637 external_name(),
3638 pkg_name->as_C_string(),
3639 loader_data->loader_name_and_id(),
3640 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3641 }
3642 } else {
3643 ResourceMark rm(THREAD);
3644 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3645 external_name(),
3646 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3647 UNNAMED_MODULE);
3648 }
3649 }
3650
3651 // Function set_classpath_index ensures that for a non-null _package_entry
3652 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3653 // It then sets the classpath_index in the package entry record.
3654 //
3655 // The classpath_index field is used to find the entry on the boot loader class
3656 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3657 // in an unnamed module. It is also used to indicate (for all packages whose
3658 // classes are loaded by the boot loader) that at least one of the package's
3659 // classes has been loaded.
3660 void InstanceKlass::set_classpath_index(s2 path_index) {
3661 if (_package_entry != nullptr) {
3662 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3663 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3664 assert(path_index != -1, "Unexpected classpath_index");
3665 _package_entry->set_classpath_index(path_index);
3666 }
3667 }
3668
3669 // different versions of is_same_class_package
3670
3671 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3672 oop classloader1 = this->class_loader();
3673 PackageEntry* classpkg1 = this->package();
3674 if (class2->is_objArray_klass()) {
3675 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3676 }
3677
3678 oop classloader2;
3679 PackageEntry* classpkg2;
3680 if (class2->is_instance_klass()) {
3681 classloader2 = class2->class_loader();
3682 classpkg2 = class2->package();
3683 } else {
3684 assert(class2->is_typeArray_klass(), "should be type array");
3685 classloader2 = nullptr;
3686 classpkg2 = nullptr;
3687 }
3688
3689 // Same package is determined by comparing class loader
3690 // and package entries. Both must be the same. This rule
3691 // applies even to classes that are defined in the unnamed
3692 // package, they still must have the same class loader.
3693 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3694 return true;
3695 }
3696
3697 return false;
3698 }
3699
3700 // return true if this class and other_class are in the same package. Classloader
3701 // and classname information is enough to determine a class's package
3702 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3703 const Symbol* other_class_name) const {
3704 if (class_loader() != other_class_loader) {
3705 return false;
3706 }
3707 if (name()->fast_compare(other_class_name) == 0) {
3708 return true;
3709 }
3710
3711 {
3712 ResourceMark rm;
3713
3714 bool bad_class_name = false;
3715 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3716 if (bad_class_name) {
3717 return false;
3718 }
3719 // Check that package_from_class_name() returns null, not "", if there is no package.
3720 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3721
3722 const Symbol* const this_package_name =
3723 this->package() != nullptr ? this->package()->name() : nullptr;
3724
3725 if (this_package_name == nullptr || other_pkg == nullptr) {
3726 // One of the two doesn't have a package. Only return true if the other
3727 // one also doesn't have a package.
3728 return this_package_name == other_pkg;
3729 }
3730
3731 // Check if package is identical
3732 return this_package_name->fast_compare(other_pkg) == 0;
3733 }
3734 }
3735
3736 static bool is_prohibited_package_slow(Symbol* class_name) {
3737 // Caller has ResourceMark
3738 int length;
3739 jchar* unicode = class_name->as_unicode(length);
3740 return (length >= 5 &&
3741 unicode[0] == 'j' &&
3742 unicode[1] == 'a' &&
3743 unicode[2] == 'v' &&
3744 unicode[3] == 'a' &&
3745 unicode[4] == '/');
3746 }
3747
3748 // Only boot and platform class loaders can define classes in "java/" packages.
3749 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3750 ClassLoaderData* loader_data,
3751 TRAPS) {
3752 if (!loader_data->is_boot_class_loader_data() &&
3753 !loader_data->is_platform_class_loader_data() &&
3754 class_name != nullptr && class_name->utf8_length() >= 5) {
3755 ResourceMark rm(THREAD);
3756 bool prohibited;
3757 const u1* base = class_name->base();
3758 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3759 prohibited = is_prohibited_package_slow(class_name);
3760 } else {
3761 char* name = class_name->as_C_string();
3762 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3763 }
3764 if (prohibited) {
3765 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3766 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3767 char* name = pkg_name->as_C_string();
3768 const char* class_loader_name = loader_data->loader_name_and_id();
3769 StringUtils::replace_no_expand(name, "/", ".");
3770 const char* msg_text1 = "Class loader (instance of): ";
3771 const char* msg_text2 = " tried to load prohibited package name: ";
3772 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3773 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3774 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3775 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3776 }
3777 }
3778 return;
3779 }
3780
3781 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3782 constantPoolHandle i_cp(THREAD, constants());
3783 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3784 int ioff = iter.inner_class_info_index();
3785 if (ioff != 0) {
3786 // Check to see if the name matches the class we're looking for
3787 // before attempting to find the class.
3788 if (i_cp->klass_name_at_matches(this, ioff)) {
3789 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3790 if (this == inner_klass) {
3791 *ooff = iter.outer_class_info_index();
3792 *noff = iter.inner_name_index();
3793 return true;
3794 }
3795 }
3796 }
3797 }
3798 return false;
3799 }
3800
3801 void InstanceKlass::check_can_be_annotated_with_NullRestricted(InstanceKlass* type, Symbol* container_klass_name, TRAPS) {
3802 assert(type->is_instance_klass(), "Sanity check");
3803 if (type->is_identity_class()) {
3804 ResourceMark rm(THREAD);
3805 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3806 err_msg("Class %s expects class %s to be a value class, but it is an identity class",
3807 container_klass_name->as_C_string(),
3808 type->external_name()));
3809 }
3810
3811 if (type->is_abstract()) {
3812 ResourceMark rm(THREAD);
3813 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3814 err_msg("Class %s expects class %s to be concrete value type, but it is an abstract class",
3815 container_klass_name->as_C_string(),
3816 type->external_name()));
3817 }
3818 }
3819
3820 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3821 InstanceKlass* outer_klass = nullptr;
3822 *inner_is_member = false;
3823 int ooff = 0, noff = 0;
3824 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3825 if (has_inner_classes_attr) {
3826 constantPoolHandle i_cp(THREAD, constants());
3827 if (ooff != 0) {
3828 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3829 if (!ok->is_instance_klass()) {
3830 // If the outer class is not an instance klass then it cannot have
3831 // declared any inner classes.
3832 ResourceMark rm(THREAD);
3833 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3834 Exceptions::fthrow(
3835 THREAD_AND_LOCATION,
3836 vmSymbols::java_lang_IncompatibleClassChangeError(),
3837 "%s and %s disagree on InnerClasses attribute",
3838 ok->external_name(),
3839 external_name());
3840 return nullptr;
3841 }
3842 outer_klass = InstanceKlass::cast(ok);
3843 *inner_is_member = true;
3844 }
3845 if (nullptr == outer_klass) {
3846 // It may be a local class; try for that.
3847 int encl_method_class_idx = enclosing_method_class_index();
3848 if (encl_method_class_idx != 0) {
3849 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3850 outer_klass = InstanceKlass::cast(ok);
3851 *inner_is_member = false;
3852 }
3853 }
3854 }
3855
3856 // If no inner class attribute found for this class.
3857 if (nullptr == outer_klass) return nullptr;
3858
3859 // Throws an exception if outer klass has not declared k as an inner klass
3860 // We need evidence that each klass knows about the other, or else
3861 // the system could allow a spoof of an inner class to gain access rights.
3862 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3863 return outer_klass;
3864 }
3865
3866 u2 InstanceKlass::compute_modifier_flags() const {
3867 u2 access = access_flags().as_unsigned_short();
3868
3869 // But check if it happens to be member class.
3870 InnerClassesIterator iter(this);
3871 for (; !iter.done(); iter.next()) {
3872 int ioff = iter.inner_class_info_index();
3873 // Inner class attribute can be zero, skip it.
3874 // Strange but true: JVM spec. allows null inner class refs.
3875 if (ioff == 0) continue;
3876
3877 // only look at classes that are already loaded
3878 // since we are looking for the flags for our self.
3879 Symbol* inner_name = constants()->klass_name_at(ioff);
3880 if (name() == inner_name) {
3881 // This is really a member class.
3882 access = iter.inner_access_flags();
3883 break;
3884 }
3885 }
3886 if (!Arguments::is_valhalla_enabled()) {
3887 // Remember to strip ACC_SUPER bit without Valhalla
3888 access &= (~JVM_ACC_SUPER);
3889 }
3890 return access;
3891 }
3892
3893 jint InstanceKlass::jvmti_class_status() const {
3894 jint result = 0;
3895
3896 if (is_linked()) {
3897 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3898 }
3899
3900 if (is_initialized()) {
3901 assert(is_linked(), "Class status is not consistent");
3902 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3903 }
3904 if (is_in_error_state()) {
3905 result |= JVMTI_CLASS_STATUS_ERROR;
3906 }
3907 return result;
3908 }
3909
3910 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3911 bool implements_interface; // initialized by method_at_itable_or_null
3912 Method* m = method_at_itable_or_null(holder, index,
3913 implements_interface); // out parameter
3914 if (m != nullptr) {
3915 assert(implements_interface, "sanity");
3916 return m;
3917 } else if (implements_interface) {
3918 // Throw AbstractMethodError since corresponding itable slot is empty.
3919 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3920 } else {
3921 // If the interface isn't implemented by the receiver class,
3922 // the VM should throw IncompatibleClassChangeError.
3923 ResourceMark rm(THREAD);
3924 stringStream ss;
3925 bool same_module = (module() == holder->module());
3926 ss.print("Receiver class %s does not implement "
3927 "the interface %s defining the method to be called "
3928 "(%s%s%s)",
3929 external_name(), holder->external_name(),
3930 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3931 (same_module) ? "" : "; ",
3932 (same_module) ? "" : holder->class_in_module_of_loader());
3933 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3934 }
3935 }
3936
3937 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3938 klassItable itable(this);
3939 for (int i = 0; i < itable.size_offset_table(); i++) {
3940 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3941 if (offset_entry->interface_klass() == holder) {
3942 implements_interface = true;
3943 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3944 Method* m = ime[index].method();
3945 return m;
3946 }
3947 }
3948 implements_interface = false;
3949 return nullptr; // offset entry not found
3950 }
3951
3952 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3953 assert(is_linked(), "required");
3954 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3955 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3956
3957 int vtable_index = Method::invalid_vtable_index;
3958 Symbol* name = intf_method->name();
3959 Symbol* signature = intf_method->signature();
3960
3961 // First check in default method array
3962 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3963 int index = find_method_index(default_methods(),
3964 name, signature,
3965 Klass::OverpassLookupMode::find,
3966 Klass::StaticLookupMode::find,
3967 Klass::PrivateLookupMode::find);
3968 if (index >= 0) {
3969 vtable_index = default_vtable_indices()->at(index);
3970 }
3971 }
3972 if (vtable_index == Method::invalid_vtable_index) {
3973 // get vtable_index for miranda methods
3974 klassVtable vt = vtable();
3975 vtable_index = vt.index_of_miranda(name, signature);
3976 }
3977 return vtable_index;
3978 }
3979
3980 #if INCLUDE_JVMTI
3981 // update default_methods for redefineclasses for methods that are
3982 // not yet in the vtable due to concurrent subclass define and superinterface
3983 // redefinition
3984 // Note: those in the vtable, should have been updated via adjust_method_entries
3985 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3986 // search the default_methods for uses of either obsolete or EMCP methods
3987 if (default_methods() != nullptr) {
3988 for (int index = 0; index < default_methods()->length(); index ++) {
3989 Method* old_method = default_methods()->at(index);
3990 if (old_method == nullptr || !old_method->is_old()) {
3991 continue; // skip uninteresting entries
3992 }
3993 assert(!old_method->is_deleted(), "default methods may not be deleted");
3994 Method* new_method = old_method->get_new_method();
3995 default_methods()->at_put(index, new_method);
3996
3997 if (log_is_enabled(Info, redefine, class, update)) {
3998 ResourceMark rm;
3999 if (!(*trace_name_printed)) {
4000 log_info(redefine, class, update)
4001 ("adjust: klassname=%s default methods from name=%s",
4002 external_name(), old_method->method_holder()->external_name());
4003 *trace_name_printed = true;
4004 }
4005 log_debug(redefine, class, update, vtables)
4006 ("default method update: %s(%s) ",
4007 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
4008 }
4009 }
4010 }
4011 }
4012 #endif // INCLUDE_JVMTI
4013
4014 // On-stack replacement stuff
4015 void InstanceKlass::add_osr_nmethod(nmethod* n) {
4016 assert_lock_strong(NMethodState_lock);
4017 #ifndef PRODUCT
4018 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
4019 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
4020 "redundant OSR recompilation detected. memory leak in CodeCache!");
4021 #endif
4022 // only one compilation can be active
4023 assert(n->is_osr_method(), "wrong kind of nmethod");
4024 n->set_osr_link(osr_nmethods_head());
4025 set_osr_nmethods_head(n);
4026 // Raise the highest osr level if necessary
4027 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
4028
4029 // Get rid of the osr methods for the same bci that have lower levels.
4030 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
4031 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
4032 if (inv != nullptr && inv->is_in_use()) {
4033 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
4034 }
4035 }
4036 }
4037
4038 // Remove osr nmethod from the list. Return true if found and removed.
4039 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
4040 // This is a short non-blocking critical region, so the no safepoint check is ok.
4041 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
4042 assert(n->is_osr_method(), "wrong kind of nmethod");
4043 nmethod* last = nullptr;
4044 nmethod* cur = osr_nmethods_head();
4045 int max_level = CompLevel_none; // Find the max comp level excluding n
4046 Method* m = n->method();
4047 // Search for match
4048 bool found = false;
4049 while(cur != nullptr && cur != n) {
4050 if (m == cur->method()) {
4051 // Find max level before n
4052 max_level = MAX2(max_level, cur->comp_level());
4053 }
4054 last = cur;
4055 cur = cur->osr_link();
4056 }
4057 nmethod* next = nullptr;
4058 if (cur == n) {
4059 found = true;
4060 next = cur->osr_link();
4061 if (last == nullptr) {
4062 // Remove first element
4063 set_osr_nmethods_head(next);
4064 } else {
4065 last->set_osr_link(next);
4066 }
4067 }
4068 n->set_osr_link(nullptr);
4069 cur = next;
4070 while (cur != nullptr) {
4071 // Find max level after n
4072 if (m == cur->method()) {
4073 max_level = MAX2(max_level, cur->comp_level());
4074 }
4075 cur = cur->osr_link();
4076 }
4077 m->set_highest_osr_comp_level(max_level);
4078 return found;
4079 }
4080
4081 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
4082 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
4083 nmethod* osr = osr_nmethods_head();
4084 int found = 0;
4085 while (osr != nullptr) {
4086 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
4087 if (osr->method() == m) {
4088 deopt_scope->mark(osr);
4089 found++;
4090 }
4091 osr = osr->osr_link();
4092 }
4093 return found;
4094 }
4095
4096 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
4097 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
4098 nmethod* osr = osr_nmethods_head();
4099 nmethod* best = nullptr;
4100 while (osr != nullptr) {
4101 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
4102 // There can be a time when a c1 osr method exists but we are waiting
4103 // for a c2 version. When c2 completes its osr nmethod we will trash
4104 // the c1 version and only be able to find the c2 version. However
4105 // while we overflow in the c1 code at back branches we don't want to
4106 // try and switch to the same code as we are already running
4107
4108 if (osr->method() == m &&
4109 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
4110 if (match_level) {
4111 if (osr->comp_level() == comp_level) {
4112 // Found a match - return it.
4113 return osr;
4114 }
4115 } else {
4116 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
4117 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
4118 // Found the best possible - return it.
4119 return osr;
4120 }
4121 best = osr;
4122 }
4123 }
4124 }
4125 osr = osr->osr_link();
4126 }
4127
4128 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
4129 if (best != nullptr && best->comp_level() >= comp_level) {
4130 return best;
4131 }
4132 return nullptr;
4133 }
4134
4135 // -----------------------------------------------------------------------------------------------------
4136 // Printing
4137
4138 static const char* state_names[] = {
4139 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
4140 };
4141
4142 static void print_vtable(intptr_t* start, int len, outputStream* st) {
4143 for (int i = 0; i < len; i++) {
4144 intptr_t e = start[i];
4145 st->print("%d : " INTPTR_FORMAT, i, e);
4146 if (MetaspaceObj::is_valid((Metadata*)e)) {
4147 st->print(" ");
4148 ((Metadata*)e)->print_value_on(st);
4149 }
4150 st->cr();
4151 }
4152 }
4153
4154 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
4155 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
4156 }
4157
4158 const char* InstanceKlass::init_state_name() const {
4159 return state_names[init_state()];
4160 }
4161
4162 const char* InstanceKlass::state2name(ClassState s) {
4163 return state_names[s];
4164 }
4165
4166 void InstanceKlass::print_class_flags(outputStream* st) const {
4167 AccessFlags flags(compute_modifier_flags());
4168 if (flags.is_public ()) st->print("public ");
4169 if (flags.is_private ()) st->print("private ");
4170 if (flags.is_protected ()) st->print("protected ");
4171 if (flags.is_static ()) st->print("static ");
4172 if (flags.is_final ()) st->print("final ");
4173 if (flags.is_interface ()) st->print("interface ");
4174 if (flags.is_abstract ()) st->print("abstract ");
4175 if (flags.is_annotation()) st->print("annotation ");
4176 if (flags.is_enum ()) st->print("enum ");
4177 if (flags.is_synthetic ()) st->print("synthetic ");
4178 if (Arguments::is_valhalla_enabled()) {
4179 if (flags.is_identity_class()) st->print("identity ");
4180 if (!flags.is_identity_class()) st->print("value " );
4181 }
4182 }
4183
4184 void InstanceKlass::print_on(outputStream* st) const {
4185 assert(is_klass(), "must be klass");
4186 Klass::print_on(st);
4187
4188 st->print(" - instance size: %d", size_helper()); st->cr();
4189 st->print(" - klass size: %d", size()); st->cr();
4190 st->print(" - access: "); print_class_flags(st); st->cr();
4191 st->print(" - flags: "); _misc_flags.print_on(st); st->cr();
4192 st->print(" - state: "); st->print_cr("%s", init_state_name());
4193 st->print(" - name: "); name()->print_value_on(st); st->cr();
4194 st->print(" - super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
4195 st->print(" - sub: ");
4196 Klass* sub = subklass();
4197 int n;
4198 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
4199 if (n < MaxSubklassPrintSize) {
4200 sub->print_value_on(st);
4201 st->print(" ");
4202 }
4203 }
4204 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
4205 st->cr();
4206
4207 if (is_interface()) {
4208 st->print_cr(" - nof implementors: %d", nof_implementors());
4209 if (nof_implementors() == 1) {
4210 st->print_cr(" - implementor: ");
4211 st->print(" ");
4212 implementor()->print_value_on(st);
4213 st->cr();
4214 }
4215 }
4216
4217 st->print(" - arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
4218 st->print(" - methods: ");
4219 print_array_on(st, methods(), [](outputStream* ost, Method* method) {
4220 method->print_value_on(ost);
4221 });
4222 st->print(" - method ordering: ");
4223 print_array_on(st, method_ordering(), [](outputStream* ost, int i) {
4224 ost->print("%d", i);
4225 });
4226 if (default_methods() != nullptr) {
4227 st->print(" - default_methods: ");
4228 print_array_on(st, default_methods(), [](outputStream* ost, Method* method) {
4229 method->print_value_on(ost);
4230 });
4231 }
4232 print_on_maybe_null(st, " - default vtable indices: ", default_vtable_indices());
4233 st->print(" - local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
4234 st->print(" - trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
4235
4236 st->print(" - secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
4237
4238 st->print(" - hash_slot: %d", hash_slot()); st->cr();
4239 st->print(" - secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
4240
4241 if (secondary_supers() != nullptr) {
4242 if (Verbose) {
4243 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
4244 st->print_cr(" - ---- secondary supers (%d words):", _secondary_supers->length());
4245 for (int i = 0; i < _secondary_supers->length(); i++) {
4246 ResourceMark rm; // for external_name()
4247 Klass* secondary_super = _secondary_supers->at(i);
4248 st->print(" - %2d:", i);
4249 if (is_hashed) {
4250 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
4251 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
4252 st->print(" dist:%02d:", distance);
4253 }
4254 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
4255 }
4256 }
4257 }
4258 st->print(" - constants: "); constants()->print_value_on(st); st->cr();
4259
4260 print_on_maybe_null(st, " - class loader data: ", class_loader_data());
4261 print_on_maybe_null(st, " - source file: ", source_file_name());
4262 if (source_debug_extension() != nullptr) {
4263 st->print(" - source debug extension: ");
4264 st->print("%s", source_debug_extension());
4265 st->cr();
4266 }
4267 print_on_maybe_null(st, " - class annotations: ", class_annotations());
4268 print_on_maybe_null(st, " - class type annotations: ", class_type_annotations());
4269 print_on_maybe_null(st, " - field annotations: ", fields_annotations());
4270 print_on_maybe_null(st, " - field type annotations: ", fields_type_annotations());
4271 {
4272 bool have_pv = false;
4273 // previous versions are linked together through the InstanceKlass
4274 for (InstanceKlass* pv_node = previous_versions();
4275 pv_node != nullptr;
4276 pv_node = pv_node->previous_versions()) {
4277 if (!have_pv)
4278 st->print(" - previous version: ");
4279 have_pv = true;
4280 pv_node->constants()->print_value_on(st);
4281 }
4282 if (have_pv) st->cr();
4283 }
4284
4285 print_on_maybe_null(st, " - generic signature: ", generic_signature());
4286 st->print(" - inner classes: "); inner_classes()->print_value_on(st); st->cr();
4287 st->print(" - nest members: "); nest_members()->print_value_on(st); st->cr();
4288 print_on_maybe_null(st, " - record components: ", record_components());
4289 st->print(" - permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
4290 st->print(" - loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
4291 if (java_mirror() != nullptr) {
4292 st->print(" - java mirror: ");
4293 java_mirror()->print_value_on(st);
4294 st->cr();
4295 } else {
4296 st->print_cr(" - java mirror: null");
4297 }
4298 st->print(" - vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
4299 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
4300 st->print(" - itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
4301 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
4302
4303 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
4304 // There is no oop so static and nonstatic printing can use the same printer.
4305 FieldPrinter field_printer(st);
4306 st->print_cr(" - ---- static fields (%d words):", static_field_size());
4307 ik->do_local_static_fields(&field_printer);
4308 st->print_cr(" - ---- non-static fields (%d words):", nonstatic_field_size());
4309 ik->print_nonstatic_fields(&field_printer);
4310
4311 st->print(" - non-static oop maps (%d entries): ", nonstatic_oop_map_count());
4312 OopMapBlock* map = start_of_nonstatic_oop_maps();
4313 OopMapBlock* end_map = map + nonstatic_oop_map_count();
4314 while (map < end_map) {
4315 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
4316 map++;
4317 }
4318 st->cr();
4319
4320 if (fieldinfo_search_table() != nullptr) {
4321 st->print_cr(" - ---- field info search table:");
4322 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
4323 }
4324 }
4325
4326 void InstanceKlass::print_value_on(outputStream* st) const {
4327 assert(is_klass(), "must be klass");
4328 if (Verbose || WizardMode) print_class_flags(st);
4329 name()->print_value_on(st);
4330 }
4331
4332 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
4333 Klass::oop_print_on(obj, st);
4334
4335 if (this == vmClasses::String_klass()) {
4336 typeArrayOop value = java_lang_String::value(obj);
4337 juint length = java_lang_String::length(obj);
4338 if (value != nullptr &&
4339 value->is_typeArray() &&
4340 length <= (juint) value->length()) {
4341 st->print(" - string: ");
4342 java_lang_String::print(obj, st);
4343 st->cr();
4344 }
4345 }
4346
4347 st->print_cr(" - ---- fields (total size %zu words):", oop_size(obj));
4348 FieldPrinter print_field(st, obj);
4349 print_nonstatic_fields(&print_field);
4350
4351 if (this == vmClasses::Class_klass()) {
4352 st->print(" - signature: ");
4353 java_lang_Class::print_signature(obj, st);
4354 st->cr();
4355 Klass* real_klass = java_lang_Class::as_Klass(obj);
4356 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4357 st->print_cr(" - ---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4358 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4359 }
4360 } else if (this == vmClasses::MethodType_klass()) {
4361 st->print(" - signature: ");
4362 java_lang_invoke_MethodType::print_signature(obj, st);
4363 st->cr();
4364 }
4365 }
4366
4367 #ifndef PRODUCT
4368
4369 bool InstanceKlass::verify_itable_index(int i) {
4370 int method_count = klassItable::method_count_for_interface(this);
4371 assert(i >= 0 && i < method_count, "index out of bounds");
4372 return true;
4373 }
4374
4375 #endif //PRODUCT
4376
4377 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4378 st->print("a ");
4379 name()->print_value_on(st);
4380 obj->print_address_on(st);
4381 if (this == vmClasses::String_klass()
4382 && java_lang_String::value(obj) != nullptr) {
4383 ResourceMark rm;
4384 int len = java_lang_String::length(obj);
4385 int plen = (len < 24 ? len : 12);
4386 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4387 st->print(" = \"%s\"", str);
4388 if (len > plen)
4389 st->print("...[%d]", len);
4390 } else if (this == vmClasses::Class_klass()) {
4391 Klass* k = java_lang_Class::as_Klass(obj);
4392 st->print(" = ");
4393 if (k != nullptr) {
4394 k->print_value_on(st);
4395 } else {
4396 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4397 st->print("%s", tname ? tname : "type?");
4398 }
4399 } else if (this == vmClasses::MethodType_klass()) {
4400 st->print(" = ");
4401 java_lang_invoke_MethodType::print_signature(obj, st);
4402 } else if (java_lang_boxing_object::is_instance(obj)) {
4403 st->print(" = ");
4404 java_lang_boxing_object::print(obj, st);
4405 } else if (this == vmClasses::LambdaForm_klass()) {
4406 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4407 if (vmentry != nullptr) {
4408 st->print(" => ");
4409 vmentry->print_value_on(st);
4410 }
4411 } else if (this == vmClasses::MemberName_klass()) {
4412 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4413 if (vmtarget != nullptr) {
4414 st->print(" = ");
4415 vmtarget->print_value_on(st);
4416 } else {
4417 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4418 oop name = java_lang_invoke_MemberName::name(obj);
4419 if (clazz != nullptr) {
4420 clazz->print_value_on(st);
4421 } else {
4422 st->print("null");
4423 }
4424 st->print(".");
4425 if (name != nullptr) {
4426 name->print_value_on(st);
4427 } else {
4428 st->print("null");
4429 }
4430 }
4431 }
4432 }
4433
4434 const char* InstanceKlass::internal_name() const {
4435 return external_name();
4436 }
4437
4438 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4439 const ModuleEntry* module_entry,
4440 const ClassFileStream* cfs) const {
4441
4442 if (ClassListWriter::is_enabled()) {
4443 ClassListWriter::write(this, cfs);
4444 }
4445
4446 print_class_load_helper(loader_data, module_entry, cfs);
4447 print_class_load_cause_logging();
4448 }
4449
4450 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4451 const ModuleEntry* module_entry,
4452 const ClassFileStream* cfs) const {
4453
4454 if (!log_is_enabled(Info, class, load)) {
4455 return;
4456 }
4457
4458 ResourceMark rm;
4459 LogMessage(class, load) msg;
4460 stringStream info_stream;
4461
4462 // Name and class hierarchy info
4463 info_stream.print("%s", external_name());
4464
4465 // Source
4466 if (cfs != nullptr) {
4467 if (cfs->source() != nullptr) {
4468 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4469 if (module_name != nullptr) {
4470 // When the boot loader created the stream, it didn't know the module name
4471 // yet. Let's format it now.
4472 if (cfs->from_boot_loader_modules_image()) {
4473 info_stream.print(" source: jrt:/%s", module_name);
4474 } else {
4475 info_stream.print(" source: %s", cfs->source());
4476 }
4477 } else {
4478 info_stream.print(" source: %s", cfs->source());
4479 }
4480 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4481 Thread* current = Thread::current();
4482 Klass* caller = current->is_Java_thread() ?
4483 JavaThread::cast(current)->security_get_caller_class(1):
4484 nullptr;
4485 // caller can be null, for example, during a JVMTI VM_Init hook
4486 if (caller != nullptr) {
4487 info_stream.print(" source: instance of %s", caller->external_name());
4488 } else {
4489 // source is unknown
4490 }
4491 } else {
4492 oop class_loader = loader_data->class_loader();
4493 info_stream.print(" source: %s", class_loader->klass()->external_name());
4494 }
4495 } else {
4496 assert(this->in_aot_cache(), "must be");
4497 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
4498 info_stream.print(" source: shared objects file (top)");
4499 } else {
4500 info_stream.print(" source: shared objects file");
4501 }
4502 }
4503
4504 msg.info("%s", info_stream.as_string());
4505
4506 if (log_is_enabled(Debug, class, load)) {
4507 stringStream debug_stream;
4508
4509 // Class hierarchy info
4510 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4511 p2i(this), p2i(super()));
4512
4513 // Interfaces
4514 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4515 debug_stream.print(" interfaces:");
4516 int length = local_interfaces()->length();
4517 for (int i = 0; i < length; i++) {
4518 debug_stream.print(" " PTR_FORMAT,
4519 p2i(local_interfaces()->at(i)));
4520 }
4521 }
4522
4523 // Class loader
4524 debug_stream.print(" loader: [");
4525 loader_data->print_value_on(&debug_stream);
4526 debug_stream.print("]");
4527
4528 // Classfile checksum
4529 if (cfs) {
4530 debug_stream.print(" bytes: %d checksum: %08x",
4531 cfs->length(),
4532 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4533 cfs->length()));
4534 }
4535
4536 msg.debug("%s", debug_stream.as_string());
4537 }
4538 }
4539
4540 void InstanceKlass::print_class_load_cause_logging() const {
4541 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4542 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4543 JavaThread* current = JavaThread::current();
4544 ResourceMark rm(current);
4545 const char* name = external_name();
4546
4547 if (LogClassLoadingCauseFor == nullptr ||
4548 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4549 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4550 return;
4551 }
4552
4553 // Log Java stack first
4554 {
4555 LogMessage(class, load, cause) msg;
4556 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4557
4558 info_stream.print_cr("Java stack when loading %s:", name);
4559 current->print_stack_on(&info_stream);
4560 }
4561
4562 // Log native stack second
4563 if (log_cause_native) {
4564 // Log to string first so that lines can be indented
4565 stringStream stack_stream;
4566 char buf[O_BUFLEN];
4567 address lastpc = nullptr;
4568 NativeStackPrinter nsp(current);
4569 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4570 true /* print_source_info */, -1 /* max stack */);
4571
4572 LogMessage(class, load, cause, native) msg;
4573 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4574 info_stream.print_cr("Native stack when loading %s:", name);
4575
4576 // Print each native stack line to the log
4577 int size = (int) stack_stream.size();
4578 char* stack = stack_stream.as_string();
4579 char* stack_end = stack + size;
4580 char* line_start = stack;
4581 for (char* p = stack; p < stack_end; p++) {
4582 if (*p == '\n') {
4583 *p = '\0';
4584 info_stream.print_cr("\t%s", line_start);
4585 line_start = p + 1;
4586 }
4587 }
4588 if (line_start < stack_end) {
4589 info_stream.print_cr("\t%s", line_start);
4590 }
4591 }
4592 }
4593 }
4594
4595 // Verification
4596
4597 class VerifyFieldClosure: public BasicOopIterateClosure {
4598 protected:
4599 template <class T> void do_oop_work(T* p) {
4600 oop obj = RawAccess<>::oop_load(p);
4601 if (!oopDesc::is_oop_or_null(obj)) {
4602 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4603 Universe::print_on(tty);
4604 guarantee(false, "boom");
4605 }
4606 }
4607 public:
4608 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4609 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4610 };
4611
4612 void InstanceKlass::verify_on(outputStream* st) {
4613 #ifndef PRODUCT
4614 // Avoid redundant verifies, this really should be in product.
4615 if (_verify_count == Universe::verify_count()) return;
4616 _verify_count = Universe::verify_count();
4617 #endif
4618
4619 // Verify Klass
4620 Klass::verify_on(st);
4621
4622 // Verify that klass is present in ClassLoaderData
4623 guarantee(class_loader_data()->contains_klass(this),
4624 "this class isn't found in class loader data");
4625
4626 // Verify vtables
4627 if (is_linked()) {
4628 // $$$ This used to be done only for m/s collections. Doing it
4629 // always seemed a valid generalization. (DLD -- 6/00)
4630 vtable().verify(st);
4631 }
4632
4633 // Verify first subklass
4634 if (subklass() != nullptr) {
4635 guarantee(subklass()->is_klass(), "should be klass");
4636 }
4637
4638 // Verify siblings
4639 Klass* super = this->super();
4640 Klass* sib = next_sibling();
4641 if (sib != nullptr) {
4642 if (sib == this) {
4643 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4644 }
4645
4646 guarantee(sib->is_klass(), "should be klass");
4647 guarantee(sib->super() == super, "siblings should have same superklass");
4648 }
4649
4650 // Verify local interfaces
4651 if (local_interfaces()) {
4652 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4653 for (int j = 0; j < local_interfaces->length(); j++) {
4654 InstanceKlass* e = local_interfaces->at(j);
4655 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4656 }
4657 }
4658
4659 // Verify transitive interfaces
4660 if (transitive_interfaces() != nullptr) {
4661 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4662 for (int j = 0; j < transitive_interfaces->length(); j++) {
4663 InstanceKlass* e = transitive_interfaces->at(j);
4664 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4665 }
4666 }
4667
4668 // Verify methods
4669 if (methods() != nullptr) {
4670 Array<Method*>* methods = this->methods();
4671 for (int j = 0; j < methods->length(); j++) {
4672 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4673 }
4674 for (int j = 0; j < methods->length() - 1; j++) {
4675 Method* m1 = methods->at(j);
4676 Method* m2 = methods->at(j + 1);
4677 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4678 }
4679 }
4680
4681 // Verify method ordering
4682 if (method_ordering() != nullptr) {
4683 Array<int>* method_ordering = this->method_ordering();
4684 int length = method_ordering->length();
4685 if (JvmtiExport::can_maintain_original_method_order() ||
4686 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4687 guarantee(length == methods()->length(), "invalid method ordering length");
4688 jlong sum = 0;
4689 for (int j = 0; j < length; j++) {
4690 int original_index = method_ordering->at(j);
4691 guarantee(original_index >= 0, "invalid method ordering index");
4692 guarantee(original_index < length, "invalid method ordering index");
4693 sum += original_index;
4694 }
4695 // Verify sum of indices 0,1,...,length-1
4696 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4697 } else {
4698 guarantee(length == 0, "invalid method ordering length");
4699 }
4700 }
4701
4702 // Verify default methods
4703 if (default_methods() != nullptr) {
4704 Array<Method*>* methods = this->default_methods();
4705 for (int j = 0; j < methods->length(); j++) {
4706 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4707 }
4708 for (int j = 0; j < methods->length() - 1; j++) {
4709 Method* m1 = methods->at(j);
4710 Method* m2 = methods->at(j + 1);
4711 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4712 }
4713 }
4714
4715 // Verify JNI static field identifiers
4716 if (jni_ids() != nullptr) {
4717 jni_ids()->verify(this);
4718 }
4719
4720 // Verify other fields
4721 if (constants() != nullptr) {
4722 guarantee(constants()->is_constantPool(), "should be constant pool");
4723 }
4724 }
4725
4726 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4727 Klass::oop_verify_on(obj, st);
4728 VerifyFieldClosure blk;
4729 obj->oop_iterate(&blk);
4730 }
4731
4732 // JNIid class for jfieldIDs only
4733 // Note to reviewers:
4734 // These JNI functions are just moved over to column 1 and not changed
4735 // in the compressed oops workspace.
4736 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4737 _holder = holder;
4738 _offset = offset;
4739 _next = next;
4740 DEBUG_ONLY(_is_static_field_id = false;)
4741 }
4742
4743 JNIid* JNIid::find(int offset) {
4744 JNIid* current = this;
4745 while (current != nullptr) {
4746 if (current->offset() == offset) return current;
4747 current = current->next();
4748 }
4749 return nullptr;
4750 }
4751
4752 void JNIid::deallocate(JNIid* current) {
4753 while (current != nullptr) {
4754 JNIid* next = current->next();
4755 delete current;
4756 current = next;
4757 }
4758 }
4759
4760 void JNIid::verify(InstanceKlass* holder) {
4761 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4762 int end_field_offset;
4763 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4764
4765 JNIid* current = this;
4766 while (current != nullptr) {
4767 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4768 #ifdef ASSERT
4769 int o = current->offset();
4770 if (current->is_static_field_id()) {
4771 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4772 }
4773 #endif
4774 current = current->next();
4775 }
4776 }
4777
4778 void InstanceKlass::set_init_state(ClassState state) {
4779 #ifdef ASSERT
4780 // TODO enable: assert(state <= initialization_error, "only store known states");
4781 bool good_state = in_aot_cache() ? (_init_state <= state)
4782 : (_init_state < state);
4783 assert(good_state || state == allocated, "illegal state transition");
4784 #endif
4785 assert(_init_thread == nullptr, "should be cleared before state change");
4786 AtomicAccess::release_store(&_init_state, state);
4787 }
4788
4789 #if INCLUDE_JVMTI
4790
4791 // RedefineClasses() support for previous versions
4792
4793 // Globally, there is at least one previous version of a class to walk
4794 // during class unloading, which is saved because old methods in the class
4795 // are still running. Otherwise the previous version list is cleaned up.
4796 bool InstanceKlass::_should_clean_previous_versions = false;
4797
4798 // Returns true if there are previous versions of a class for class
4799 // unloading only. Also resets the flag to false. purge_previous_version
4800 // will set the flag to true if there are any left, i.e., if there's any
4801 // work to do for next time. This is to avoid the expensive code cache
4802 // walk in CLDG::clean_deallocate_lists().
4803 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4804 bool ret = _should_clean_previous_versions;
4805 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4806 ret ? "true" : "false");
4807 _should_clean_previous_versions = false;
4808 return ret;
4809 }
4810
4811 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4812 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4813 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4814 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4815 Array<Method*>* method_refs = klass->methods();
4816 for (int k = 0; k < method_refs->length(); k++) {
4817 Method* method = method_refs->at(k);
4818 // Only need to clear obsolete methods.
4819 if (method != nullptr && method->is_obsolete()) {
4820 method->clear_jmethod_id();
4821 }
4822 }
4823 }
4824
4825 // Purge previous versions before adding new previous versions of the class and
4826 // during class unloading.
4827 void InstanceKlass::purge_previous_version_list() {
4828 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4829 assert(has_been_redefined(), "Should only be called for main class");
4830
4831 // Quick exit.
4832 if (previous_versions() == nullptr) {
4833 return;
4834 }
4835
4836 // This klass has previous versions so see what we can cleanup
4837 // while it is safe to do so.
4838
4839 int deleted_count = 0; // leave debugging breadcrumbs
4840 int live_count = 0;
4841 ClassLoaderData* loader_data = class_loader_data();
4842 assert(loader_data != nullptr, "should never be null");
4843
4844 ResourceMark rm;
4845 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4846
4847 // previous versions are linked together through the InstanceKlass
4848 InstanceKlass* pv_node = previous_versions();
4849 InstanceKlass* last = this;
4850 int version = 0;
4851
4852 // check the previous versions list
4853 for (; pv_node != nullptr; ) {
4854
4855 ConstantPool* pvcp = pv_node->constants();
4856 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4857
4858 if (!pvcp->on_stack()) {
4859 // If the constant pool isn't on stack, none of the methods
4860 // are executing. Unlink this previous_version.
4861 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4862 // so will be deallocated during the next phase of class unloading.
4863 log_trace(redefine, class, iklass, purge)
4864 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4865 // Unlink from previous version list.
4866 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4867 InstanceKlass* next = pv_node->previous_versions();
4868 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4869 pv_node->link_previous_versions(nullptr); // point next to null
4870 last->link_previous_versions(next);
4871 // Delete this node directly. Nothing is referring to it and we don't
4872 // want it to increase the counter for metadata to delete in CLDG.
4873 MetadataFactory::free_metadata(loader_data, pv_node);
4874 pv_node = next;
4875 deleted_count++;
4876 version++;
4877 continue;
4878 } else {
4879 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4880 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4881 live_count++;
4882 if (pvcp->in_aot_cache()) {
4883 // Shared previous versions can never be removed so no cleaning is needed.
4884 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4885 } else {
4886 // Previous version alive, set that clean is needed for next time.
4887 _should_clean_previous_versions = true;
4888 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4889 }
4890 }
4891
4892 // next previous version
4893 last = pv_node;
4894 pv_node = pv_node->previous_versions();
4895 version++;
4896 }
4897 log_trace(redefine, class, iklass, purge)
4898 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4899 }
4900
4901 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4902 int emcp_method_count) {
4903 int obsolete_method_count = old_methods->length() - emcp_method_count;
4904
4905 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4906 _previous_versions != nullptr) {
4907 // We have a mix of obsolete and EMCP methods so we have to
4908 // clear out any matching EMCP method entries the hard way.
4909 int local_count = 0;
4910 for (int i = 0; i < old_methods->length(); i++) {
4911 Method* old_method = old_methods->at(i);
4912 if (old_method->is_obsolete()) {
4913 // only obsolete methods are interesting
4914 Symbol* m_name = old_method->name();
4915 Symbol* m_signature = old_method->signature();
4916
4917 // previous versions are linked together through the InstanceKlass
4918 int j = 0;
4919 for (InstanceKlass* prev_version = _previous_versions;
4920 prev_version != nullptr;
4921 prev_version = prev_version->previous_versions(), j++) {
4922
4923 Array<Method*>* method_refs = prev_version->methods();
4924 for (int k = 0; k < method_refs->length(); k++) {
4925 Method* method = method_refs->at(k);
4926
4927 if (!method->is_obsolete() &&
4928 method->name() == m_name &&
4929 method->signature() == m_signature) {
4930 // The current RedefineClasses() call has made all EMCP
4931 // versions of this method obsolete so mark it as obsolete
4932 log_trace(redefine, class, iklass, add)
4933 ("%s(%s): flush obsolete method @%d in version @%d",
4934 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4935
4936 method->set_is_obsolete();
4937 break;
4938 }
4939 }
4940
4941 // The previous loop may not find a matching EMCP method, but
4942 // that doesn't mean that we can optimize and not go any
4943 // further back in the PreviousVersion generations. The EMCP
4944 // method for this generation could have already been made obsolete,
4945 // but there still may be an older EMCP method that has not
4946 // been made obsolete.
4947 }
4948
4949 if (++local_count >= obsolete_method_count) {
4950 // no more obsolete methods so bail out now
4951 break;
4952 }
4953 }
4954 }
4955 }
4956 }
4957
4958 // Save the scratch_class as the previous version if any of the methods are running.
4959 // The previous_versions are used to set breakpoints in EMCP methods and they are
4960 // also used to clean MethodData links to redefined methods that are no longer running.
4961 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4962 int emcp_method_count) {
4963 assert(Thread::current()->is_VM_thread(),
4964 "only VMThread can add previous versions");
4965
4966 ResourceMark rm;
4967 log_trace(redefine, class, iklass, add)
4968 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4969
4970 // Clean out old previous versions for this class
4971 purge_previous_version_list();
4972
4973 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4974 // a previous redefinition may be made obsolete by this redefinition.
4975 Array<Method*>* old_methods = scratch_class->methods();
4976 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4977
4978 // If the constant pool for this previous version of the class
4979 // is not marked as being on the stack, then none of the methods
4980 // in this previous version of the class are on the stack so
4981 // we don't need to add this as a previous version.
4982 ConstantPool* cp_ref = scratch_class->constants();
4983 if (!cp_ref->on_stack()) {
4984 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4985 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4986 return;
4987 }
4988
4989 // Add previous version if any methods are still running or if this is
4990 // a shared class which should never be removed.
4991 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4992 scratch_class->link_previous_versions(previous_versions());
4993 link_previous_versions(scratch_class);
4994 if (cp_ref->in_aot_cache()) {
4995 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4996 } else {
4997 // We only set clean_previous_versions flag for processing during class
4998 // unloading for non-shared classes.
4999 _should_clean_previous_versions = true;
5000 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
5001 }
5002 } // end add_previous_version()
5003
5004 #endif // INCLUDE_JVMTI
5005
5006 Method* InstanceKlass::method_with_idnum(int idnum) const {
5007 Method* m = nullptr;
5008 if (idnum < methods()->length()) {
5009 m = methods()->at(idnum);
5010 }
5011 if (m == nullptr || m->method_idnum() != idnum) {
5012 for (int index = 0; index < methods()->length(); ++index) {
5013 m = methods()->at(index);
5014 if (m->method_idnum() == idnum) {
5015 return m;
5016 }
5017 }
5018 // None found, return null for the caller to handle.
5019 return nullptr;
5020 }
5021 return m;
5022 }
5023
5024
5025 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
5026 if (idnum >= methods()->length()) {
5027 return nullptr;
5028 }
5029 Method* m = methods()->at(idnum);
5030 if (m != nullptr && m->orig_method_idnum() == idnum) {
5031 return m;
5032 }
5033 // Obsolete method idnum does not match the original idnum
5034 for (int index = 0; index < methods()->length(); ++index) {
5035 m = methods()->at(index);
5036 if (m->orig_method_idnum() == idnum) {
5037 return m;
5038 }
5039 }
5040 // None found, return null for the caller to handle.
5041 return nullptr;
5042 }
5043
5044
5045 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
5046 const InstanceKlass* holder = get_klass_version(version);
5047 if (holder == nullptr) {
5048 return nullptr; // The version of klass is gone, no method is found
5049 }
5050 return holder->method_with_orig_idnum(idnum);
5051 }
5052
5053 #if INCLUDE_JVMTI
5054 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
5055 return _cached_class_file;
5056 }
5057
5058 jint InstanceKlass::get_cached_class_file_len() {
5059 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
5060 }
5061
5062 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
5063 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
5064 }
5065 #endif
5066
5067 // Make a step iterating over the class hierarchy under the root class.
5068 // Skips subclasses if requested.
5069 void ClassHierarchyIterator::next() {
5070 assert(_current != nullptr, "required");
5071 if (_visit_subclasses && _current->subklass() != nullptr) {
5072 _current = _current->subklass();
5073 return; // visit next subclass
5074 }
5075 _visit_subclasses = true; // reset
5076 while (_current->next_sibling() == nullptr && _current != _root) {
5077 _current = _current->java_super(); // backtrack; no more sibling subclasses left
5078 }
5079 if (_current == _root) {
5080 // Iteration is over (back at root after backtracking). Invalidate the iterator.
5081 _current = nullptr;
5082 return;
5083 }
5084 _current = _current->next_sibling();
5085 return; // visit next sibling subclass
5086 }