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