1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "cds/aotClassInitializer.hpp"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/cdsEnumKlass.hpp"
30 #include "cds/classListWriter.hpp"
31 #include "cds/heapShared.hpp"
32 #include "cds/metaspaceShared.hpp"
33 #include "classfile/classFileParser.hpp"
34 #include "classfile/classFileStream.hpp"
35 #include "classfile/classLoader.hpp"
36 #include "classfile/classLoaderData.inline.hpp"
37 #include "classfile/javaClasses.hpp"
38 #include "classfile/moduleEntry.hpp"
39 #include "classfile/systemDictionary.hpp"
40 #include "classfile/systemDictionaryShared.hpp"
41 #include "classfile/verifier.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "code/codeCache.hpp"
45 #include "code/dependencyContext.hpp"
46 #include "compiler/compilationPolicy.hpp"
47 #include "compiler/compileBroker.hpp"
48 #include "gc/shared/collectedHeap.inline.hpp"
49 #include "interpreter/bytecodeStream.hpp"
50 #include "interpreter/oopMapCache.hpp"
51 #include "interpreter/rewriter.hpp"
52 #include "jvm.h"
53 #include "jvmtifiles/jvmti.h"
54 #include "logging/log.hpp"
55 #include "klass.inline.hpp"
56 #include "logging/logMessage.hpp"
57 #include "logging/logStream.hpp"
58 #include "memory/allocation.inline.hpp"
59 #include "memory/iterator.inline.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceClosure.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "memory/universe.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/constantPool.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/synchronizer.hpp"
93 #include "runtime/threads.hpp"
94 #include "services/classLoadingService.hpp"
95 #include "services/finalizerService.hpp"
96 #include "services/threadService.hpp"
97 #include "utilities/dtrace.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/macros.hpp"
100 #include "utilities/stringUtils.hpp"
101 #include "utilities/pair.hpp"
102 #ifdef COMPILER1
103 #include "c1/c1_Compiler.hpp"
104 #endif
105 #if INCLUDE_JFR
106 #include "jfr/jfrEvents.hpp"
107 #endif
108
109 #ifdef DTRACE_ENABLED
110
111
112 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
113 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
114 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
115 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
116 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
117 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
118 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
119 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
120 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
121 { \
122 char* data = nullptr; \
123 int len = 0; \
124 Symbol* clss_name = name(); \
125 if (clss_name != nullptr) { \
126 data = (char*)clss_name->bytes(); \
127 len = clss_name->utf8_length(); \
128 } \
129 HOTSPOT_CLASS_INITIALIZATION_##type( \
130 data, len, (void*)class_loader(), thread_type); \
131 }
132
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
134 { \
135 char* data = nullptr; \
136 int len = 0; \
137 Symbol* clss_name = name(); \
138 if (clss_name != nullptr) { \
139 data = (char*)clss_name->bytes(); \
140 len = clss_name->utf8_length(); \
141 } \
142 HOTSPOT_CLASS_INITIALIZATION_##type( \
143 data, len, (void*)class_loader(), thread_type, wait); \
144 }
145
146 #else // ndef DTRACE_ENABLED
147
148 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
149 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
150
151 #endif // ndef DTRACE_ENABLED
152
153 bool InstanceKlass::_finalization_enabled = true;
154
155 static inline bool is_class_loader(const Symbol* class_name,
156 const ClassFileParser& parser) {
157 assert(class_name != nullptr, "invariant");
158
159 if (class_name == vmSymbols::java_lang_ClassLoader()) {
160 return true;
161 }
162
163 if (vmClasses::ClassLoader_klass_loaded()) {
164 const Klass* const super_klass = parser.super_klass();
165 if (super_klass != nullptr) {
166 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
167 return true;
168 }
169 }
170 }
171 return false;
172 }
173
174 static inline bool is_stack_chunk_class(const Symbol* class_name,
175 const ClassLoaderData* loader_data) {
176 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
177 loader_data->is_the_null_class_loader_data());
178 }
179
180 // private: called to verify that k is a static member of this nest.
181 // We know that k is an instance class in the same package and hence the
182 // same classloader.
183 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
184 assert(!is_hidden(), "unexpected hidden class");
185 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
186 if (log_is_enabled(Trace, class, nestmates)) {
187 ResourceMark rm(current);
188 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
189 k->external_name(), this->external_name());
190 }
191 return false;
192 }
193
194 if (log_is_enabled(Trace, class, nestmates)) {
195 ResourceMark rm(current);
196 log_trace(class, nestmates)("Checking nest membership of %s in %s",
197 k->external_name(), this->external_name());
198 }
199
200 // Check for the named class in _nest_members.
201 // We don't resolve, or load, any classes.
202 for (int i = 0; i < _nest_members->length(); i++) {
203 int cp_index = _nest_members->at(i);
204 Symbol* name = _constants->klass_name_at(cp_index);
205 if (name == k->name()) {
206 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
207 return true;
208 }
209 }
210 log_trace(class, nestmates)("- class is NOT a nest member!");
211 return false;
212 }
213
214 // Called to verify that k is a permitted subclass of this class
215 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
216 Thread* current = Thread::current();
217 assert(k != nullptr, "sanity check");
218 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
219 "unexpected empty _permitted_subclasses array");
220
221 if (log_is_enabled(Trace, class, sealed)) {
222 ResourceMark rm(current);
223 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
224 k->external_name(), this->external_name());
225 }
226
227 // Check that the class and its super are in the same module.
228 if (k->module() != this->module()) {
229 ResourceMark rm(current);
230 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
231 k->external_name(), this->external_name());
232 return false;
233 }
234
235 if (!k->is_public() && !is_same_class_package(k)) {
236 ResourceMark rm(current);
237 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
238 k->external_name(), this->external_name());
239 return false;
240 }
241
242 for (int i = 0; i < _permitted_subclasses->length(); i++) {
243 int cp_index = _permitted_subclasses->at(i);
244 Symbol* name = _constants->klass_name_at(cp_index);
245 if (name == k->name()) {
246 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
247 return true;
248 }
249 }
250 log_trace(class, sealed)("- class is NOT a permitted subclass!");
251 return false;
252 }
253
254 // Return nest-host class, resolving, validating and saving it if needed.
255 // In cases where this is called from a thread that cannot do classloading
256 // (such as a native JIT thread) then we simply return null, which in turn
257 // causes the access check to return false. Such code will retry the access
258 // from a more suitable environment later. Otherwise the _nest_host is always
259 // set once this method returns.
260 // Any errors from nest-host resolution must be preserved so they can be queried
261 // from higher-level access checking code, and reported as part of access checking
262 // exceptions.
263 // VirtualMachineErrors are propagated with a null return.
264 // Under any conditions where the _nest_host can be set to non-null the resulting
265 // value of it and, if applicable, the nest host resolution/validation error,
266 // are idempotent.
267 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
268 InstanceKlass* nest_host_k = _nest_host;
269 if (nest_host_k != nullptr) {
270 return nest_host_k;
271 }
272
273 ResourceMark rm(THREAD);
274
275 // need to resolve and save our nest-host class.
276 if (_nest_host_index != 0) { // we have a real nest_host
277 // Before trying to resolve check if we're in a suitable context
278 bool can_resolve = THREAD->can_call_java();
279 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
280 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
281 this->external_name());
282 return nullptr; // sentinel to say "try again from a different context"
283 }
284
285 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
286 this->external_name(),
287 _constants->klass_name_at(_nest_host_index)->as_C_string());
288
289 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
290 if (HAS_PENDING_EXCEPTION) {
291 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
292 return nullptr; // propagate VMEs
293 }
294 stringStream ss;
295 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
296 ss.print("Nest host resolution of %s with host %s failed: ",
297 this->external_name(), target_host_class);
298 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
299 const char* msg = ss.as_string(true /* on C-heap */);
300 constantPoolHandle cph(THREAD, constants());
301 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
302 CLEAR_PENDING_EXCEPTION;
303
304 log_trace(class, nestmates)("%s", msg);
305 } else {
306 // A valid nest-host is an instance class in the current package that lists this
307 // class as a nest member. If any of these conditions are not met the class is
308 // its own nest-host.
309 const char* error = nullptr;
310
311 // JVMS 5.4.4 indicates package check comes first
312 if (is_same_class_package(k)) {
313 // Now check actual membership. We can't be a member if our "host" is
314 // not an instance class.
315 if (k->is_instance_klass()) {
316 nest_host_k = InstanceKlass::cast(k);
317 bool is_member = nest_host_k->has_nest_member(THREAD, this);
318 if (is_member) {
319 _nest_host = nest_host_k; // save resolved nest-host value
320
321 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
322 this->external_name(), k->external_name());
323 return nest_host_k;
324 } else {
325 error = "current type is not listed as a nest member";
326 }
327 } else {
328 error = "host is not an instance class";
329 }
330 } else {
331 error = "types are in different packages";
332 }
333
334 // something went wrong, so record what and log it
335 {
336 stringStream ss;
337 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
338 this->external_name(),
339 this->class_loader_data()->loader_name_and_id(),
340 k->external_name(),
341 k->class_loader_data()->loader_name_and_id(),
342 error);
343 const char* msg = ss.as_string(true /* on C-heap */);
344 constantPoolHandle cph(THREAD, constants());
345 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
346 log_trace(class, nestmates)("%s", msg);
347 }
348 }
349 } else {
350 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
351 this->external_name());
352 }
353
354 // Either not in an explicit nest, or else an error occurred, so
355 // the nest-host is set to `this`. Any thread that sees this assignment
356 // will also see any setting of nest_host_error(), if applicable.
357 return (_nest_host = this);
358 }
359
360 // Dynamic nest member support: set this class's nest host to the given class.
361 // This occurs as part of the class definition, as soon as the instanceKlass
362 // has been created and doesn't require further resolution. The code:
363 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
364 // results in:
365 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
366 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
367 // We also know the "host" is a valid nest-host in the same package so we can
368 // assert some of those facts.
369 void InstanceKlass::set_nest_host(InstanceKlass* host) {
370 assert(is_hidden(), "must be a hidden class");
371 assert(host != nullptr, "null nest host specified");
372 assert(_nest_host == nullptr, "current class has resolved nest-host");
373 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
374 nest_host_error());
375 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
376 (host->_nest_host == host), "proposed host is not a valid nest-host");
377 // Can't assert this as package is not set yet:
378 // assert(is_same_class_package(host), "proposed host is in wrong package");
379
380 if (log_is_enabled(Trace, class, nestmates)) {
381 ResourceMark rm;
382 const char* msg = "";
383 // a hidden class does not expect a statically defined nest-host
384 if (_nest_host_index > 0) {
385 msg = "(the NestHost attribute in the current class is ignored)";
386 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
387 msg = "(the NestMembers attribute in the current class is ignored)";
388 }
389 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
390 this->external_name(),
391 host->external_name(),
392 msg);
393 }
394 // set dynamic nest host
395 _nest_host = host;
396 // Record dependency to keep nest host from being unloaded before this class.
397 ClassLoaderData* this_key = class_loader_data();
398 assert(this_key != nullptr, "sanity");
399 this_key->record_dependency(host);
400 }
401
402 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
403 // or we are k's nest_host - all of which is covered by comparing the two
404 // resolved_nest_hosts.
405 // Any exceptions (i.e. VMEs) are propagated.
406 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
407
408 assert(this != k, "this should be handled by higher-level code");
409
410 // Per JVMS 5.4.4 we first resolve and validate the current class, then
411 // the target class k.
412
413 InstanceKlass* cur_host = nest_host(CHECK_false);
414 if (cur_host == nullptr) {
415 return false;
416 }
417
418 Klass* k_nest_host = k->nest_host(CHECK_false);
419 if (k_nest_host == nullptr) {
420 return false;
421 }
422
423 bool access = (cur_host == k_nest_host);
424
425 ResourceMark rm(THREAD);
426 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
427 this->external_name(),
428 access ? "" : "NOT ",
429 k->external_name());
430 return access;
431 }
432
433 const char* InstanceKlass::nest_host_error() {
434 if (_nest_host_index == 0) {
435 return nullptr;
436 } else {
437 constantPoolHandle cph(Thread::current(), constants());
438 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
439 }
440 }
441
442 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
443 bool use_class_space, TRAPS) throw() {
444 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
445 }
446
447 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
448 const int size = InstanceKlass::size(parser.vtable_size(),
449 parser.itable_size(),
450 nonstatic_oop_map_size(parser.total_oop_map_count()),
451 parser.is_interface());
452
453 const Symbol* const class_name = parser.class_name();
454 assert(class_name != nullptr, "invariant");
455 ClassLoaderData* loader_data = parser.loader_data();
456 assert(loader_data != nullptr, "invariant");
457
458 InstanceKlass* ik;
459 const bool use_class_space = parser.klass_needs_narrow_id();
460
461 // Allocation
462 if (parser.is_instance_ref_klass()) {
463 // java.lang.ref.Reference
464 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
465 } else if (class_name == vmSymbols::java_lang_Class()) {
466 // mirror - java.lang.Class
467 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
468 } else if (is_stack_chunk_class(class_name, loader_data)) {
469 // stack chunk
470 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
471 } else if (is_class_loader(class_name, parser)) {
472 // class loader - java.lang.ClassLoader
473 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
474 } else {
475 // normal
476 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
477 }
478
479 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
480 assert(CompressedKlassPointers::is_encodable(ik),
481 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
482 }
483
484 // Check for pending exception before adding to the loader data and incrementing
485 // class count. Can get OOM here.
486 if (HAS_PENDING_EXCEPTION) {
487 return nullptr;
488 }
489
490 return ik;
491 }
492
493
494 // copy method ordering from resource area to Metaspace
495 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
496 if (m != nullptr) {
497 // allocate a new array and copy contents (memcpy?)
498 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
499 for (int i = 0; i < m->length(); i++) {
500 _method_ordering->at_put(i, m->at(i));
501 }
502 } else {
503 _method_ordering = Universe::the_empty_int_array();
504 }
505 }
506
507 // create a new array of vtable_indices for default methods
508 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
509 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
510 assert(default_vtable_indices() == nullptr, "only create once");
511 set_default_vtable_indices(vtable_indices);
512 return vtable_indices;
513 }
514
515
516 InstanceKlass::InstanceKlass() {
517 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
518 }
519
520 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
521 Klass(kind),
522 _nest_members(nullptr),
523 _nest_host(nullptr),
524 _permitted_subclasses(nullptr),
525 _record_components(nullptr),
526 _static_field_size(parser.static_field_size()),
527 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
528 _itable_len(parser.itable_size()),
529 _nest_host_index(0),
530 _init_state(allocated),
531 _reference_type(reference_type),
532 _init_thread(nullptr)
533 {
534 set_vtable_length(parser.vtable_size());
535 set_access_flags(parser.access_flags());
536 if (parser.is_hidden()) set_is_hidden();
537 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
538 false));
539
540 assert(nullptr == _methods, "underlying memory not zeroed?");
541 assert(is_instance_klass(), "is layout incorrect?");
542 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
543 }
544
545 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
546 Array<Method*>* methods) {
547 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
548 !methods->is_shared()) {
549 for (int i = 0; i < methods->length(); i++) {
550 Method* method = methods->at(i);
551 if (method == nullptr) continue; // maybe null if error processing
552 // Only want to delete methods that are not executing for RedefineClasses.
553 // The previous version will point to them so they're not totally dangling
554 assert (!method->on_stack(), "shouldn't be called with methods on stack");
555 MetadataFactory::free_metadata(loader_data, method);
556 }
557 MetadataFactory::free_array<Method*>(loader_data, methods);
558 }
559 }
560
561 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
562 const Klass* super_klass,
563 Array<InstanceKlass*>* local_interfaces,
564 Array<InstanceKlass*>* transitive_interfaces) {
565 // Only deallocate transitive interfaces if not empty, same as super class
566 // or same as local interfaces. See code in parseClassFile.
567 Array<InstanceKlass*>* ti = transitive_interfaces;
568 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
569 // check that the interfaces don't come from super class
570 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
571 InstanceKlass::cast(super_klass)->transitive_interfaces();
572 if (ti != sti && ti != nullptr && !ti->is_shared()) {
573 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
574 }
575 }
576
577 // local interfaces can be empty
578 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
579 local_interfaces != nullptr && !local_interfaces->is_shared()) {
580 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
581 }
582 }
583
584 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
585 Array<RecordComponent*>* record_components) {
586 if (record_components != nullptr && !record_components->is_shared()) {
587 for (int i = 0; i < record_components->length(); i++) {
588 RecordComponent* record_component = record_components->at(i);
589 MetadataFactory::free_metadata(loader_data, record_component);
590 }
591 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
592 }
593 }
594
595 // This function deallocates the metadata and C heap pointers that the
596 // InstanceKlass points to.
597 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
598 // Orphan the mirror first, CMS thinks it's still live.
599 if (java_mirror() != nullptr) {
600 java_lang_Class::set_klass(java_mirror(), nullptr);
601 }
602
603 // Also remove mirror from handles
604 loader_data->remove_handle(_java_mirror);
605
606 // Need to take this class off the class loader data list.
607 loader_data->remove_class(this);
608
609 // The array_klass for this class is created later, after error handling.
610 // For class redefinition, we keep the original class so this scratch class
611 // doesn't have an array class. Either way, assert that there is nothing
612 // to deallocate.
613 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
614
615 // Release C heap allocated data that this points to, which includes
616 // reference counting symbol names.
617 // Can't release the constant pool or MethodData C heap data here because the constant
618 // pool can be deallocated separately from the InstanceKlass for default methods and
619 // redefine classes. MethodData can also be released separately.
620 release_C_heap_structures(/* release_sub_metadata */ false);
621
622 deallocate_methods(loader_data, methods());
623 set_methods(nullptr);
624
625 deallocate_record_components(loader_data, record_components());
626 set_record_components(nullptr);
627
628 if (method_ordering() != nullptr &&
629 method_ordering() != Universe::the_empty_int_array() &&
630 !method_ordering()->is_shared()) {
631 MetadataFactory::free_array<int>(loader_data, method_ordering());
632 }
633 set_method_ordering(nullptr);
634
635 // default methods can be empty
636 if (default_methods() != nullptr &&
637 default_methods() != Universe::the_empty_method_array() &&
638 !default_methods()->is_shared()) {
639 MetadataFactory::free_array<Method*>(loader_data, default_methods());
640 }
641 // Do NOT deallocate the default methods, they are owned by superinterfaces.
642 set_default_methods(nullptr);
643
644 // default methods vtable indices can be empty
645 if (default_vtable_indices() != nullptr &&
646 !default_vtable_indices()->is_shared()) {
647 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
648 }
649 set_default_vtable_indices(nullptr);
650
651
652 // This array is in Klass, but remove it with the InstanceKlass since
653 // this place would be the only caller and it can share memory with transitive
654 // interfaces.
655 if (secondary_supers() != nullptr &&
656 secondary_supers() != Universe::the_empty_klass_array() &&
657 // see comments in compute_secondary_supers about the following cast
658 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
659 !secondary_supers()->is_shared()) {
660 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
661 }
662 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
663
664 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
665 set_transitive_interfaces(nullptr);
666 set_local_interfaces(nullptr);
667
668 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
669 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
670 }
671 set_fieldinfo_stream(nullptr);
672
673 if (fields_status() != nullptr && !fields_status()->is_shared()) {
674 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
675 }
676 set_fields_status(nullptr);
677
678 // If a method from a redefined class is using this constant pool, don't
679 // delete it, yet. The new class's previous version will point to this.
680 if (constants() != nullptr) {
681 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
682 if (!constants()->is_shared()) {
683 MetadataFactory::free_metadata(loader_data, constants());
684 }
685 // Delete any cached resolution errors for the constant pool
686 SystemDictionary::delete_resolution_error(constants());
687
688 set_constants(nullptr);
689 }
690
691 if (inner_classes() != nullptr &&
692 inner_classes() != Universe::the_empty_short_array() &&
693 !inner_classes()->is_shared()) {
694 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
695 }
696 set_inner_classes(nullptr);
697
698 if (nest_members() != nullptr &&
699 nest_members() != Universe::the_empty_short_array() &&
700 !nest_members()->is_shared()) {
701 MetadataFactory::free_array<jushort>(loader_data, nest_members());
702 }
703 set_nest_members(nullptr);
704
705 if (permitted_subclasses() != nullptr &&
706 permitted_subclasses() != Universe::the_empty_short_array() &&
707 !permitted_subclasses()->is_shared()) {
708 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
709 }
710 set_permitted_subclasses(nullptr);
711
712 // We should deallocate the Annotations instance if it's not in shared spaces.
713 if (annotations() != nullptr && !annotations()->is_shared()) {
714 MetadataFactory::free_metadata(loader_data, annotations());
715 }
716 set_annotations(nullptr);
717
718 SystemDictionaryShared::handle_class_unloading(this);
719
720 #if INCLUDE_CDS_JAVA_HEAP
721 if (CDSConfig::is_dumping_heap()) {
722 HeapShared::remove_scratch_objects(this);
723 }
724 #endif
725 }
726
727 bool InstanceKlass::is_record() const {
728 return _record_components != nullptr &&
729 is_final() &&
730 java_super() == vmClasses::Record_klass();
731 }
732
733 bool InstanceKlass::is_sealed() const {
734 return _permitted_subclasses != nullptr &&
735 _permitted_subclasses != Universe::the_empty_short_array();
736 }
737
738 // JLS 8.9: An enum class is either implicitly final and derives
739 // from java.lang.Enum, or else is implicitly sealed to its
740 // anonymous subclasses. This query detects both kinds.
741 // It does not validate the finality or
742 // sealing conditions: it merely checks for a super of Enum.
743 // This is sufficient for recognizing well-formed enums.
744 bool InstanceKlass::is_enum_subclass() const {
745 InstanceKlass* s = java_super();
746 return (s == vmClasses::Enum_klass() ||
747 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
748 }
749
750 bool InstanceKlass::should_be_initialized() const {
751 return !is_initialized();
752 }
753
754 klassItable InstanceKlass::itable() const {
755 return klassItable(const_cast<InstanceKlass*>(this));
756 }
757
758 // JVMTI spec thinks there are signers and protection domain in the
759 // instanceKlass. These accessors pretend these fields are there.
760 // The hprof specification also thinks these fields are in InstanceKlass.
761 oop InstanceKlass::protection_domain() const {
762 // return the protection_domain from the mirror
763 return java_lang_Class::protection_domain(java_mirror());
764 }
765
766 objArrayOop InstanceKlass::signers() const {
767 // return the signers from the mirror
768 return java_lang_Class::signers(java_mirror());
769 }
770
771 oop InstanceKlass::init_lock() const {
772 // return the init lock from the mirror
773 oop lock = java_lang_Class::init_lock(java_mirror());
774 // Prevent reordering with any access of initialization state
775 OrderAccess::loadload();
776 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
777 "only fully initialized state can have a null lock");
778 return lock;
779 }
780
781 // Set the initialization lock to null so the object can be GC'ed. Any racing
782 // threads to get this lock will see a null lock and will not lock.
783 // That's okay because they all check for initialized state after getting
784 // the lock and return.
785 void InstanceKlass::fence_and_clear_init_lock() {
786 // make sure previous stores are all done, notably the init_state.
787 OrderAccess::storestore();
788 java_lang_Class::clear_init_lock(java_mirror());
789 assert(!is_not_initialized(), "class must be initialized now");
790 }
791
792
793 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
794 // process. The step comments refers to the procedure described in that section.
795 // Note: implementation moved to static method to expose the this pointer.
796 void InstanceKlass::initialize(TRAPS) {
797 if (this->should_be_initialized()) {
798 initialize_impl(CHECK);
799 // Note: at this point the class may be initialized
800 // OR it may be in the state of being initialized
801 // in case of recursive initialization!
802 } else {
803 assert(is_initialized(), "sanity check");
804 }
805 }
806
807 #ifdef ASSERT
808 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
809 assert(has_aot_initialized_mirror(), "must be");
810
811 InstanceKlass* s = java_super();
812 if (s != nullptr) {
813 DEBUG_ONLY(ResourceMark rm);
814 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
815 s->external_name(), external_name());
816 s->assert_no_clinit_will_run_for_aot_initialized_class();
817 }
818
819 Array<InstanceKlass*>* interfaces = local_interfaces();
820 int len = interfaces->length();
821 for (int i = 0; i < len; i++) {
822 InstanceKlass* intf = interfaces->at(i);
823 if (!intf->is_initialized()) {
824 ResourceMark rm;
825 // Note: an interface needs to be marked as is_initialized() only if
826 // - it has a <clinit>
827 // - it has declared a default method.
828 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
829 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
830 intf->external_name(), external_name());
831 }
832 }
833 }
834 #endif
835
836 #if INCLUDE_CDS
837 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
838 assert(has_aot_initialized_mirror(), "must be");
839 assert(CDSConfig::is_loading_heap(), "must be");
840 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
841 assert_no_clinit_will_run_for_aot_initialized_class();
842
843 if (is_initialized()) {
844 return;
845 }
846
847 if (log_is_enabled(Info, cds, init)) {
848 ResourceMark rm;
849 log_info(cds, init)("%s (aot-inited)", external_name());
850 }
851
852 link_class(CHECK);
853
854 #ifdef ASSERT
855 {
856 Handle h_init_lock(THREAD, init_lock());
857 ObjectLocker ol(h_init_lock, THREAD);
858 assert(!is_initialized(), "sanity");
859 assert(!is_being_initialized(), "sanity");
860 assert(!is_in_error_state(), "sanity");
861 }
862 #endif
863
864 set_init_thread(THREAD);
865 AOTClassInitializer::call_runtime_setup(THREAD, this);
866 set_initialization_state_and_notify(fully_initialized, CHECK);
867 }
868 #endif
869
870 bool InstanceKlass::verify_code(TRAPS) {
871 // 1) Verify the bytecodes
872 return Verifier::verify(this, should_verify_class(), THREAD);
873 }
874
875 void InstanceKlass::link_class(TRAPS) {
876 assert(is_loaded(), "must be loaded");
877 if (!is_linked()) {
878 link_class_impl(CHECK);
879 }
880 }
881
882 // Called to verify that a class can link during initialization, without
883 // throwing a VerifyError.
884 bool InstanceKlass::link_class_or_fail(TRAPS) {
885 assert(is_loaded(), "must be loaded");
886 if (!is_linked()) {
887 link_class_impl(CHECK_false);
888 }
889 return is_linked();
890 }
891
892 bool InstanceKlass::link_class_impl(TRAPS) {
893 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
894 // This is for CDS static dump only -- we use the in_error_state to indicate that
895 // the class has failed verification. Throwing the NoClassDefFoundError here is just
896 // a convenient way to stop repeat attempts to verify the same (bad) class.
897 //
898 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
899 // if we are executing Java code. This is not a problem for CDS dumping phase since
900 // it doesn't execute any Java code.
901 ResourceMark rm(THREAD);
902 // Names are all known to be < 64k so we know this formatted message is not excessively large.
903 Exceptions::fthrow(THREAD_AND_LOCATION,
904 vmSymbols::java_lang_NoClassDefFoundError(),
905 "Class %s, or one of its supertypes, failed class initialization",
906 external_name());
907 return false;
908 }
909 // return if already verified
910 if (is_linked()) {
911 return true;
912 }
913
914 // Timing
915 // timer handles recursion
916 JavaThread* jt = THREAD;
917
918 // link super class before linking this class
919 Klass* super_klass = super();
920 if (super_klass != nullptr) {
921 if (super_klass->is_interface()) { // check if super class is an interface
922 ResourceMark rm(THREAD);
923 // Names are all known to be < 64k so we know this formatted message is not excessively large.
924 Exceptions::fthrow(
925 THREAD_AND_LOCATION,
926 vmSymbols::java_lang_IncompatibleClassChangeError(),
927 "class %s has interface %s as super class",
928 external_name(),
929 super_klass->external_name()
930 );
931 return false;
932 }
933
934 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
935 ik_super->link_class_impl(CHECK_false);
936 }
937
938 // link all interfaces implemented by this class before linking this class
939 Array<InstanceKlass*>* interfaces = local_interfaces();
940 int num_interfaces = interfaces->length();
941 for (int index = 0; index < num_interfaces; index++) {
942 InstanceKlass* interk = interfaces->at(index);
943 interk->link_class_impl(CHECK_false);
944 }
945
946 // in case the class is linked in the process of linking its superclasses
947 if (is_linked()) {
948 return true;
949 }
950
951 // trace only the link time for this klass that includes
952 // the verification time
953 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
954 ClassLoader::perf_class_link_selftime(),
955 ClassLoader::perf_classes_linked(),
956 jt->get_thread_stat()->perf_recursion_counts_addr(),
957 jt->get_thread_stat()->perf_timers_addr(),
958 PerfClassTraceTime::CLASS_LINK);
959
960 // verification & rewriting
961 {
962 HandleMark hm(THREAD);
963 Handle h_init_lock(THREAD, init_lock());
964 ObjectLocker ol(h_init_lock, jt);
965 // rewritten will have been set if loader constraint error found
966 // on an earlier link attempt
967 // don't verify or rewrite if already rewritten
968 //
969
970 if (!is_linked()) {
971 if (!is_rewritten()) {
972 if (is_shared()) {
973 assert(!verified_at_dump_time(), "must be");
974 }
975 {
976 bool verify_ok = verify_code(THREAD);
977 if (!verify_ok) {
978 return false;
979 }
980 }
981
982 // Just in case a side-effect of verify linked this class already
983 // (which can sometimes happen since the verifier loads classes
984 // using custom class loaders, which are free to initialize things)
985 if (is_linked()) {
986 return true;
987 }
988
989 // also sets rewritten
990 rewrite_class(CHECK_false);
991 } else if (is_shared()) {
992 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
993 }
994
995 // relocate jsrs and link methods after they are all rewritten
996 link_methods(CHECK_false);
997
998 // Initialize the vtable and interface table after
999 // methods have been rewritten since rewrite may
1000 // fabricate new Method*s.
1001 // also does loader constraint checking
1002 //
1003 // initialize_vtable and initialize_itable need to be rerun
1004 // for a shared class if
1005 // 1) the class is loaded by custom class loader or
1006 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1007 // 3) the class was not verified during dump time
1008 bool need_init_table = true;
1009 if (is_shared() && verified_at_dump_time() &&
1010 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1011 need_init_table = false;
1012 }
1013 if (need_init_table) {
1014 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1015 itable().initialize_itable_and_check_constraints(CHECK_false);
1016 }
1017 #ifdef ASSERT
1018 vtable().verify(tty, true);
1019 // In case itable verification is ever added.
1020 // itable().verify(tty, true);
1021 #endif
1022 if (Universe::is_fully_initialized()) {
1023 DeoptimizationScope deopt_scope;
1024 {
1025 // Now mark all code that assumes the class is not linked.
1026 // Set state under the Compile_lock also.
1027 MutexLocker ml(THREAD, Compile_lock);
1028
1029 set_init_state(linked);
1030 CodeCache::mark_dependents_on(&deopt_scope, this);
1031 }
1032 // Perform the deopt handshake outside Compile_lock.
1033 deopt_scope.deoptimize_marked();
1034 } else {
1035 set_init_state(linked);
1036 }
1037 if (JvmtiExport::should_post_class_prepare()) {
1038 JvmtiExport::post_class_prepare(THREAD, this);
1039 }
1040 }
1041 }
1042 return true;
1043 }
1044
1045 // Rewrite the byte codes of all of the methods of a class.
1046 // The rewriter must be called exactly once. Rewriting must happen after
1047 // verification but before the first method of the class is executed.
1048 void InstanceKlass::rewrite_class(TRAPS) {
1049 assert(is_loaded(), "must be loaded");
1050 if (is_rewritten()) {
1051 assert(is_shared(), "rewriting an unshared class?");
1052 return;
1053 }
1054 Rewriter::rewrite(this, CHECK);
1055 set_rewritten();
1056 }
1057
1058 // Now relocate and link method entry points after class is rewritten.
1059 // This is outside is_rewritten flag. In case of an exception, it can be
1060 // executed more than once.
1061 void InstanceKlass::link_methods(TRAPS) {
1062 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1063
1064 int len = methods()->length();
1065 for (int i = len-1; i >= 0; i--) {
1066 methodHandle m(THREAD, methods()->at(i));
1067
1068 // Set up method entry points for compiler and interpreter .
1069 m->link_method(m, CHECK);
1070 }
1071 }
1072
1073 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1074 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1075 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1076 for (int i = 0; i < local_interfaces()->length(); ++i) {
1077 InstanceKlass* ik = local_interfaces()->at(i);
1078
1079 // Initialization is depth first search ie. we start with top of the inheritance tree
1080 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1081 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1082 if (ik->has_nonstatic_concrete_methods()) {
1083 ik->initialize_super_interfaces(CHECK);
1084 }
1085
1086 // Only initialize() interfaces that "declare" concrete methods.
1087 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1088 ik->initialize(CHECK);
1089 }
1090 }
1091 }
1092
1093 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1094 static InitializationErrorTable* _initialization_error_table;
1095
1096 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1097 // Create the same exception with a message indicating the thread name,
1098 // and the StackTraceElements.
1099 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1100 ResourceMark rm(current);
1101 if (init_error.is_null()) {
1102 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1103
1104 // We failed to create the new exception, most likely due to either out-of-memory or
1105 // a stackoverflow error. If the original exception was either of those then we save
1106 // the shared, pre-allocated, stackless, instance of that exception.
1107 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1108 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1109 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1110 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1111 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1112 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1113 } else {
1114 return;
1115 }
1116 }
1117
1118 MutexLocker ml(current, ClassInitError_lock);
1119 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1120 bool created;
1121 if (_initialization_error_table == nullptr) {
1122 _initialization_error_table = new (mtClass) InitializationErrorTable();
1123 }
1124 _initialization_error_table->put_if_absent(this, elem, &created);
1125 assert(created, "Initialization is single threaded");
1126 log_trace(class, init)("Initialization error added for class %s", external_name());
1127 }
1128
1129 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1130 MutexLocker ml(current, ClassInitError_lock);
1131 if (_initialization_error_table == nullptr) {
1132 return nullptr;
1133 }
1134 OopHandle* h = _initialization_error_table->get(this);
1135 return (h != nullptr) ? h->resolve() : nullptr;
1136 }
1137
1138 // Need to remove entries for unloaded classes.
1139 void InstanceKlass::clean_initialization_error_table() {
1140 struct InitErrorTableCleaner {
1141 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1142 if (!ik->is_loader_alive()) {
1143 h.release(Universe::vm_global());
1144 return true;
1145 } else {
1146 return false;
1147 }
1148 }
1149 };
1150
1151 assert_locked_or_safepoint(ClassInitError_lock);
1152 InitErrorTableCleaner cleaner;
1153 if (_initialization_error_table != nullptr) {
1154 _initialization_error_table->unlink(&cleaner);
1155 }
1156 }
1157
1158 void InstanceKlass::initialize_impl(TRAPS) {
1159 HandleMark hm(THREAD);
1160
1161 // Make sure klass is linked (verified) before initialization
1162 // A class could already be verified, since it has been reflected upon.
1163 link_class(CHECK);
1164
1165 DTRACE_CLASSINIT_PROBE(required, -1);
1166
1167 bool wait = false;
1168
1169 JavaThread* jt = THREAD;
1170
1171 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1172
1173 // refer to the JVM book page 47 for description of steps
1174 // Step 1
1175 {
1176 Handle h_init_lock(THREAD, init_lock());
1177 ObjectLocker ol(h_init_lock, jt);
1178
1179 // Step 2
1180 // If we were to use wait() instead of waitInterruptibly() then
1181 // we might end up throwing IE from link/symbol resolution sites
1182 // that aren't expected to throw. This would wreak havoc. See 6320309.
1183 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1184 if (debug_logging_enabled) {
1185 ResourceMark rm(jt);
1186 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1187 jt->name(), external_name(), init_thread_name());
1188 }
1189 wait = true;
1190 jt->set_class_to_be_initialized(this);
1191 ol.wait_uninterruptibly(jt);
1192 jt->set_class_to_be_initialized(nullptr);
1193 }
1194
1195 // Step 3
1196 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1197 if (debug_logging_enabled) {
1198 ResourceMark rm(jt);
1199 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1200 jt->name(), external_name());
1201 }
1202 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1203 return;
1204 }
1205
1206 // Step 4
1207 if (is_initialized()) {
1208 if (debug_logging_enabled) {
1209 ResourceMark rm(jt);
1210 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1211 jt->name(), external_name());
1212 }
1213 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1214 return;
1215 }
1216
1217 // Step 5
1218 if (is_in_error_state()) {
1219 if (debug_logging_enabled) {
1220 ResourceMark rm(jt);
1221 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1222 jt->name(), external_name());
1223 }
1224
1225 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1226 ResourceMark rm(THREAD);
1227 Handle cause(THREAD, get_initialization_error(THREAD));
1228
1229 stringStream ss;
1230 ss.print("Could not initialize class %s", external_name());
1231 if (cause.is_null()) {
1232 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1233 } else {
1234 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1235 ss.as_string(), cause);
1236 }
1237 } else {
1238
1239 // Step 6
1240 set_init_state(being_initialized);
1241 set_init_thread(jt);
1242 if (debug_logging_enabled) {
1243 ResourceMark rm(jt);
1244 log_debug(class, init)("Thread \"%s\" is initializing %s",
1245 jt->name(), external_name());
1246 }
1247 }
1248 }
1249
1250 // Step 7
1251 // Next, if C is a class rather than an interface, initialize it's super class and super
1252 // interfaces.
1253 if (!is_interface()) {
1254 Klass* super_klass = super();
1255 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1256 super_klass->initialize(THREAD);
1257 }
1258 // If C implements any interface that declares a non-static, concrete method,
1259 // the initialization of C triggers initialization of its super interfaces.
1260 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1261 // having a superinterface that declares, non-static, concrete methods
1262 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1263 initialize_super_interfaces(THREAD);
1264 }
1265
1266 // If any exceptions, complete abruptly, throwing the same exception as above.
1267 if (HAS_PENDING_EXCEPTION) {
1268 Handle e(THREAD, PENDING_EXCEPTION);
1269 CLEAR_PENDING_EXCEPTION;
1270 {
1271 EXCEPTION_MARK;
1272 add_initialization_error(THREAD, e);
1273 // Locks object, set state, and notify all waiting threads
1274 set_initialization_state_and_notify(initialization_error, THREAD);
1275 CLEAR_PENDING_EXCEPTION;
1276 }
1277 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1278 THROW_OOP(e());
1279 }
1280 }
1281
1282
1283 // Step 8
1284 {
1285 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1286 if (class_initializer() != nullptr) {
1287 // Timer includes any side effects of class initialization (resolution,
1288 // etc), but not recursive entry into call_class_initializer().
1289 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1290 ClassLoader::perf_class_init_selftime(),
1291 ClassLoader::perf_classes_inited(),
1292 jt->get_thread_stat()->perf_recursion_counts_addr(),
1293 jt->get_thread_stat()->perf_timers_addr(),
1294 PerfClassTraceTime::CLASS_CLINIT);
1295 call_class_initializer(THREAD);
1296 } else {
1297 // The elapsed time is so small it's not worth counting.
1298 if (UsePerfData) {
1299 ClassLoader::perf_classes_inited()->inc();
1300 }
1301 call_class_initializer(THREAD);
1302 }
1303 }
1304
1305 // Step 9
1306 if (!HAS_PENDING_EXCEPTION) {
1307 set_initialization_state_and_notify(fully_initialized, CHECK);
1308 debug_only(vtable().verify(tty, true);)
1309 }
1310 else {
1311 // Step 10 and 11
1312 Handle e(THREAD, PENDING_EXCEPTION);
1313 CLEAR_PENDING_EXCEPTION;
1314 // JVMTI has already reported the pending exception
1315 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1316 JvmtiExport::clear_detected_exception(jt);
1317 {
1318 EXCEPTION_MARK;
1319 add_initialization_error(THREAD, e);
1320 set_initialization_state_and_notify(initialization_error, THREAD);
1321 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1322 // JVMTI has already reported the pending exception
1323 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1324 JvmtiExport::clear_detected_exception(jt);
1325 }
1326 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1327 if (e->is_a(vmClasses::Error_klass())) {
1328 THROW_OOP(e());
1329 } else {
1330 JavaCallArguments args(e);
1331 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1332 vmSymbols::throwable_void_signature(),
1333 &args);
1334 }
1335 }
1336 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1337 }
1338
1339
1340 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1341 Handle h_init_lock(THREAD, init_lock());
1342 if (h_init_lock() != nullptr) {
1343 ObjectLocker ol(h_init_lock, THREAD);
1344 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1345 set_init_state(state);
1346 fence_and_clear_init_lock();
1347 ol.notify_all(CHECK);
1348 } else {
1349 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1350 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1351 set_init_state(state);
1352 }
1353 }
1354
1355 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1356 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1357 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1358 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1359
1360 DeoptimizationScope deopt_scope;
1361 {
1362 MutexLocker ml(current, Compile_lock);
1363
1364 set_init_state(InstanceKlass::loaded);
1365 // make sure init_state store is already done.
1366 // The compiler reads the hierarchy outside of the Compile_lock.
1367 // Access ordering is used to add to hierarchy.
1368
1369 // Link into hierarchy.
1370 append_to_sibling_list(); // add to superklass/sibling list
1371 process_interfaces(); // handle all "implements" declarations
1372
1373 // Now mark all code that depended on old class hierarchy.
1374 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1375 if (Universe::is_fully_initialized()) {
1376 CodeCache::mark_dependents_on(&deopt_scope, this);
1377 }
1378 }
1379 // Perform the deopt handshake outside Compile_lock.
1380 deopt_scope.deoptimize_marked();
1381 }
1382
1383
1384 InstanceKlass* InstanceKlass::implementor() const {
1385 InstanceKlass* volatile* ik = adr_implementor();
1386 if (ik == nullptr) {
1387 return nullptr;
1388 } else {
1389 // This load races with inserts, and therefore needs acquire.
1390 InstanceKlass* ikls = Atomic::load_acquire(ik);
1391 if (ikls != nullptr && !ikls->is_loader_alive()) {
1392 return nullptr; // don't return unloaded class
1393 } else {
1394 return ikls;
1395 }
1396 }
1397 }
1398
1399
1400 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1401 assert_locked_or_safepoint(Compile_lock);
1402 assert(is_interface(), "not interface");
1403 InstanceKlass* volatile* addr = adr_implementor();
1404 assert(addr != nullptr, "null addr");
1405 if (addr != nullptr) {
1406 Atomic::release_store(addr, ik);
1407 }
1408 }
1409
1410 int InstanceKlass::nof_implementors() const {
1411 InstanceKlass* ik = implementor();
1412 if (ik == nullptr) {
1413 return 0;
1414 } else if (ik != this) {
1415 return 1;
1416 } else {
1417 return 2;
1418 }
1419 }
1420
1421 // The embedded _implementor field can only record one implementor.
1422 // When there are more than one implementors, the _implementor field
1423 // is set to the interface Klass* itself. Following are the possible
1424 // values for the _implementor field:
1425 // null - no implementor
1426 // implementor Klass* - one implementor
1427 // self - more than one implementor
1428 //
1429 // The _implementor field only exists for interfaces.
1430 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1431 if (Universe::is_fully_initialized()) {
1432 assert_lock_strong(Compile_lock);
1433 }
1434 assert(is_interface(), "not interface");
1435 // Filter out my subinterfaces.
1436 // (Note: Interfaces are never on the subklass list.)
1437 if (ik->is_interface()) return;
1438
1439 // Filter out subclasses whose supers already implement me.
1440 // (Note: CHA must walk subclasses of direct implementors
1441 // in order to locate indirect implementors.)
1442 InstanceKlass* super_ik = ik->java_super();
1443 if (super_ik != nullptr && super_ik->implements_interface(this))
1444 // We only need to check one immediate superclass, since the
1445 // implements_interface query looks at transitive_interfaces.
1446 // Any supers of the super have the same (or fewer) transitive_interfaces.
1447 return;
1448
1449 InstanceKlass* iklass = implementor();
1450 if (iklass == nullptr) {
1451 set_implementor(ik);
1452 } else if (iklass != this && iklass != ik) {
1453 // There is already an implementor. Use itself as an indicator of
1454 // more than one implementors.
1455 set_implementor(this);
1456 }
1457
1458 // The implementor also implements the transitive_interfaces
1459 for (int index = 0; index < local_interfaces()->length(); index++) {
1460 local_interfaces()->at(index)->add_implementor(ik);
1461 }
1462 }
1463
1464 void InstanceKlass::init_implementor() {
1465 if (is_interface()) {
1466 set_implementor(nullptr);
1467 }
1468 }
1469
1470
1471 void InstanceKlass::process_interfaces() {
1472 // link this class into the implementors list of every interface it implements
1473 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1474 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1475 InstanceKlass* interf = local_interfaces()->at(i);
1476 assert(interf->is_interface(), "expected interface");
1477 interf->add_implementor(this);
1478 }
1479 }
1480
1481 bool InstanceKlass::can_be_primary_super_slow() const {
1482 if (is_interface())
1483 return false;
1484 else
1485 return Klass::can_be_primary_super_slow();
1486 }
1487
1488 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1489 Array<InstanceKlass*>* transitive_interfaces) {
1490 // The secondaries are the implemented interfaces.
1491 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1492 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1493 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1494 int num_secondaries = num_extra_slots + interfaces->length();
1495 if (num_secondaries == 0) {
1496 // Must share this for correct bootstrapping!
1497 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1498 return nullptr;
1499 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1500 // We will reuse the transitive interfaces list if we're certain
1501 // it's in hash order.
1502 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1503 set_secondary_supers(interfaces, bitmap);
1504 return nullptr;
1505 }
1506 // Copy transitive interfaces to a temporary growable array to be constructed
1507 // into the secondary super list with extra slots.
1508 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1509 for (int i = 0; i < interfaces->length(); i++) {
1510 secondaries->push(interfaces->at(i));
1511 }
1512 return secondaries;
1513 }
1514
1515 bool InstanceKlass::implements_interface(Klass* k) const {
1516 if (this == k) return true;
1517 assert(k->is_interface(), "should be an interface class");
1518 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1519 if (transitive_interfaces()->at(i) == k) {
1520 return true;
1521 }
1522 }
1523 return false;
1524 }
1525
1526 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1527 // Verify direct super interface
1528 if (this == k) return true;
1529 assert(k->is_interface(), "should be an interface class");
1530 for (int i = 0; i < local_interfaces()->length(); i++) {
1531 if (local_interfaces()->at(i) == k) {
1532 return true;
1533 }
1534 }
1535 return false;
1536 }
1537
1538 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1539 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1540 size_t size = objArrayOopDesc::object_size(length);
1541 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1542 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1543 /* do_zero */ true, CHECK_NULL);
1544 return o;
1545 }
1546
1547 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1548 if (TraceFinalizerRegistration) {
1549 tty->print("Registered ");
1550 i->print_value_on(tty);
1551 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1552 }
1553 instanceHandle h_i(THREAD, i);
1554 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1555 JavaValue result(T_VOID);
1556 JavaCallArguments args(h_i);
1557 methodHandle mh(THREAD, Universe::finalizer_register_method());
1558 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1559 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1560 return h_i();
1561 }
1562
1563 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1564 assert(!is_abstract() && !is_interface(), "Should not create this object");
1565 size_t size = size_helper(); // Query before forming handle.
1566 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1567 }
1568
1569 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1570 Klass* k = java_lang_Class::as_Klass(java_class);
1571 if (k == nullptr) {
1572 ResourceMark rm(THREAD);
1573 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1574 }
1575 InstanceKlass* ik = cast(k);
1576 ik->check_valid_for_instantiation(false, CHECK_NULL);
1577 ik->initialize(CHECK_NULL);
1578 return ik->allocate_instance(THREAD);
1579 }
1580
1581 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1582 return instanceHandle(THREAD, allocate_instance(THREAD));
1583 }
1584
1585 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1586 if (is_interface() || is_abstract()) {
1587 ResourceMark rm(THREAD);
1588 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1589 : vmSymbols::java_lang_InstantiationException(), external_name());
1590 }
1591 if (this == vmClasses::Class_klass()) {
1592 ResourceMark rm(THREAD);
1593 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1594 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1595 }
1596 }
1597
1598 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1599 // Need load-acquire for lock-free read
1600 if (array_klasses_acquire() == nullptr) {
1601
1602 // Recursively lock array allocation
1603 RecursiveLocker rl(MultiArray_lock, THREAD);
1604
1605 // Check if another thread created the array klass while we were waiting for the lock.
1606 if (array_klasses() == nullptr) {
1607 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1608 // use 'release' to pair with lock-free load
1609 release_set_array_klasses(k);
1610 }
1611 }
1612
1613 // array_klasses() will always be set at this point
1614 ObjArrayKlass* ak = array_klasses();
1615 assert(ak != nullptr, "should be set");
1616 return ak->array_klass(n, THREAD);
1617 }
1618
1619 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1620 // Need load-acquire for lock-free read
1621 ObjArrayKlass* oak = array_klasses_acquire();
1622 if (oak == nullptr) {
1623 return nullptr;
1624 } else {
1625 return oak->array_klass_or_null(n);
1626 }
1627 }
1628
1629 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1630 return array_klass(1, THREAD);
1631 }
1632
1633 ArrayKlass* InstanceKlass::array_klass_or_null() {
1634 return array_klass_or_null(1);
1635 }
1636
1637 static int call_class_initializer_counter = 0; // for debugging
1638
1639 Method* InstanceKlass::class_initializer() const {
1640 Method* clinit = find_method(
1641 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1642 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1643 return clinit;
1644 }
1645 return nullptr;
1646 }
1647
1648 void InstanceKlass::call_class_initializer(TRAPS) {
1649 if (ReplayCompiles &&
1650 (ReplaySuppressInitializers == 1 ||
1651 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1652 // Hide the existence of the initializer for the purpose of replaying the compile
1653 return;
1654 }
1655
1656 #if INCLUDE_CDS
1657 // This is needed to ensure the consistency of the archived heap objects.
1658 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1659 AOTClassInitializer::call_runtime_setup(THREAD, this);
1660 return;
1661 } else if (has_archived_enum_objs()) {
1662 assert(is_shared(), "must be");
1663 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1664 if (initialized) {
1665 return;
1666 }
1667 }
1668 #endif
1669
1670 methodHandle h_method(THREAD, class_initializer());
1671 assert(!is_initialized(), "we cannot initialize twice");
1672 LogTarget(Info, class, init) lt;
1673 if (lt.is_enabled()) {
1674 ResourceMark rm(THREAD);
1675 LogStream ls(lt);
1676 ls.print("%d Initializing ", call_class_initializer_counter++);
1677 name()->print_value_on(&ls);
1678 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1679 h_method() == nullptr ? "(no method)" : "", p2i(this),
1680 THREAD->name());
1681 }
1682 if (h_method() != nullptr) {
1683 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1684 JavaCallArguments args; // No arguments
1685 JavaValue result(T_VOID);
1686 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1687 }
1688 }
1689
1690 // If a class that implements this interface is initialized, is the JVM required
1691 // to first execute a <clinit> method declared in this interface,
1692 // or (if also_check_supers==true) any of the super types of this interface?
1693 //
1694 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1695 // an interface, then let SC be its superclass and let SI1, ..., SIn
1696 // be all superinterfaces of C (whether direct or indirect) that
1697 // declare at least one non-abstract, non-static method.
1698 //
1699 // So when an interface is initialized, it does not look at its
1700 // supers. But a proper class will ensure that all of its supers have
1701 // run their <clinit> methods, except that it disregards interfaces
1702 // that lack a non-static concrete method (i.e., a default method).
1703 // Therefore, you should probably call this method only when the
1704 // current class is a super of some proper class, not an interface.
1705 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1706 assert(is_interface(), "must be");
1707
1708 if (!has_nonstatic_concrete_methods()) {
1709 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1710 return false;
1711 }
1712
1713 // JVMS 5.5. Initialization
1714 // ...If C is an interface that declares a non-abstract,
1715 // non-static method, the initialization of a class that
1716 // implements C directly or indirectly.
1717 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1718 return true;
1719 }
1720 if (also_check_supers) {
1721 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1722 for (int i = 0; i < all_ifs->length(); ++i) {
1723 InstanceKlass* super_intf = all_ifs->at(i);
1724 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1725 return true;
1726 }
1727 }
1728 }
1729 return false;
1730 }
1731
1732 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1733 InterpreterOopMap* entry_for) {
1734 // Lazily create the _oop_map_cache at first request.
1735 // Load_acquire is needed to safely get instance published with CAS by another thread.
1736 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1737 if (oop_map_cache == nullptr) {
1738 // Try to install new instance atomically.
1739 oop_map_cache = new OopMapCache();
1740 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1741 if (other != nullptr) {
1742 // Someone else managed to install before us, ditch local copy and use the existing one.
1743 delete oop_map_cache;
1744 oop_map_cache = other;
1745 }
1746 }
1747 // _oop_map_cache is constant after init; lookup below does its own locking.
1748 oop_map_cache->lookup(method, bci, entry_for);
1749 }
1750
1751 bool InstanceKlass::contains_field_offset(int offset) {
1752 fieldDescriptor fd;
1753 return find_field_from_offset(offset, false, &fd);
1754 }
1755
1756 FieldInfo InstanceKlass::field(int index) const {
1757 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1758 if (fs.index() == index) {
1759 return fs.to_FieldInfo();
1760 }
1761 }
1762 fatal("Field not found");
1763 return FieldInfo();
1764 }
1765
1766 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1767 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1768 Symbol* f_name = fs.name();
1769 Symbol* f_sig = fs.signature();
1770 if (f_name == name && f_sig == sig) {
1771 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1772 return true;
1773 }
1774 }
1775 return false;
1776 }
1777
1778
1779 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1780 const int n = local_interfaces()->length();
1781 for (int i = 0; i < n; i++) {
1782 Klass* intf1 = local_interfaces()->at(i);
1783 assert(intf1->is_interface(), "just checking type");
1784 // search for field in current interface
1785 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1786 assert(fd->is_static(), "interface field must be static");
1787 return intf1;
1788 }
1789 // search for field in direct superinterfaces
1790 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1791 if (intf2 != nullptr) return intf2;
1792 }
1793 // otherwise field lookup fails
1794 return nullptr;
1795 }
1796
1797
1798 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1799 // search order according to newest JVM spec (5.4.3.2, p.167).
1800 // 1) search for field in current klass
1801 if (find_local_field(name, sig, fd)) {
1802 return const_cast<InstanceKlass*>(this);
1803 }
1804 // 2) search for field recursively in direct superinterfaces
1805 { Klass* intf = find_interface_field(name, sig, fd);
1806 if (intf != nullptr) return intf;
1807 }
1808 // 3) apply field lookup recursively if superclass exists
1809 { Klass* supr = super();
1810 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1811 }
1812 // 4) otherwise field lookup fails
1813 return nullptr;
1814 }
1815
1816
1817 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1818 // search order according to newest JVM spec (5.4.3.2, p.167).
1819 // 1) search for field in current klass
1820 if (find_local_field(name, sig, fd)) {
1821 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1822 }
1823 // 2) search for field recursively in direct superinterfaces
1824 if (is_static) {
1825 Klass* intf = find_interface_field(name, sig, fd);
1826 if (intf != nullptr) return intf;
1827 }
1828 // 3) apply field lookup recursively if superclass exists
1829 { Klass* supr = super();
1830 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1831 }
1832 // 4) otherwise field lookup fails
1833 return nullptr;
1834 }
1835
1836
1837 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1838 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1839 if (fs.offset() == offset) {
1840 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1841 if (fd->is_static() == is_static) return true;
1842 }
1843 }
1844 return false;
1845 }
1846
1847
1848 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1849 Klass* klass = const_cast<InstanceKlass*>(this);
1850 while (klass != nullptr) {
1851 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1852 return true;
1853 }
1854 klass = klass->super();
1855 }
1856 return false;
1857 }
1858
1859
1860 void InstanceKlass::methods_do(void f(Method* method)) {
1861 // Methods aren't stable until they are loaded. This can be read outside
1862 // a lock through the ClassLoaderData for profiling
1863 // Redefined scratch classes are on the list and need to be cleaned
1864 if (!is_loaded() && !is_scratch_class()) {
1865 return;
1866 }
1867
1868 int len = methods()->length();
1869 for (int index = 0; index < len; index++) {
1870 Method* m = methods()->at(index);
1871 assert(m->is_method(), "must be method");
1872 f(m);
1873 }
1874 }
1875
1876
1877 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1878 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1879 if (fs.access_flags().is_static()) {
1880 fieldDescriptor& fd = fs.field_descriptor();
1881 cl->do_field(&fd);
1882 }
1883 }
1884 }
1885
1886
1887 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1888 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1889 if (fs.access_flags().is_static()) {
1890 fieldDescriptor& fd = fs.field_descriptor();
1891 f(&fd, mirror, CHECK);
1892 }
1893 }
1894 }
1895
1896 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1897 InstanceKlass* super = superklass();
1898 if (super != nullptr) {
1899 super->do_nonstatic_fields(cl);
1900 }
1901 fieldDescriptor fd;
1902 int length = java_fields_count();
1903 for (int i = 0; i < length; i += 1) {
1904 fd.reinitialize(this, i);
1905 if (!fd.is_static()) {
1906 cl->do_field(&fd);
1907 }
1908 }
1909 }
1910
1911 // first in Pair is offset, second is index.
1912 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1913 return a->first - b->first;
1914 }
1915
1916 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1917 InstanceKlass* super = superklass();
1918 if (super != nullptr) {
1919 super->print_nonstatic_fields(cl);
1920 }
1921 ResourceMark rm;
1922 fieldDescriptor fd;
1923 // In DebugInfo nonstatic fields are sorted by offset.
1924 GrowableArray<Pair<int,int> > fields_sorted;
1925 int i = 0;
1926 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1927 if (!fs.access_flags().is_static()) {
1928 fd = fs.field_descriptor();
1929 Pair<int,int> f(fs.offset(), fs.index());
1930 fields_sorted.push(f);
1931 i++;
1932 }
1933 }
1934 if (i > 0) {
1935 int length = i;
1936 assert(length == fields_sorted.length(), "duh");
1937 fields_sorted.sort(compare_fields_by_offset);
1938 for (int i = 0; i < length; i++) {
1939 fd.reinitialize(this, fields_sorted.at(i).second);
1940 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1941 cl->do_field(&fd);
1942 }
1943 }
1944 }
1945
1946 #ifdef ASSERT
1947 static int linear_search(const Array<Method*>* methods,
1948 const Symbol* name,
1949 const Symbol* signature) {
1950 const int len = methods->length();
1951 for (int index = 0; index < len; index++) {
1952 const Method* const m = methods->at(index);
1953 assert(m->is_method(), "must be method");
1954 if (m->signature() == signature && m->name() == name) {
1955 return index;
1956 }
1957 }
1958 return -1;
1959 }
1960 #endif
1961
1962 bool InstanceKlass::_disable_method_binary_search = false;
1963
1964 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1965 int len = methods->length();
1966 int l = 0;
1967 int h = len - 1;
1968 while (l <= h) {
1969 Method* m = methods->at(l);
1970 if (m->name() == name) {
1971 return l;
1972 }
1973 l++;
1974 }
1975 return -1;
1976 }
1977
1978 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1979 if (_disable_method_binary_search) {
1980 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
1981 // At the final stage of dynamic dumping, the methods array may not be sorted
1982 // by ascending addresses of their names, so we can't use binary search anymore.
1983 // However, methods with the same name are still laid out consecutively inside the
1984 // methods array, so let's look for the first one that matches.
1985 return linear_search(methods, name);
1986 }
1987
1988 int len = methods->length();
1989 int l = 0;
1990 int h = len - 1;
1991
1992 // methods are sorted by ascending addresses of their names, so do binary search
1993 while (l <= h) {
1994 int mid = (l + h) >> 1;
1995 Method* m = methods->at(mid);
1996 assert(m->is_method(), "must be method");
1997 int res = m->name()->fast_compare(name);
1998 if (res == 0) {
1999 return mid;
2000 } else if (res < 0) {
2001 l = mid + 1;
2002 } else {
2003 h = mid - 1;
2004 }
2005 }
2006 return -1;
2007 }
2008
2009 // find_method looks up the name/signature in the local methods array
2010 Method* InstanceKlass::find_method(const Symbol* name,
2011 const Symbol* signature) const {
2012 return find_method_impl(name, signature,
2013 OverpassLookupMode::find,
2014 StaticLookupMode::find,
2015 PrivateLookupMode::find);
2016 }
2017
2018 Method* InstanceKlass::find_method_impl(const Symbol* name,
2019 const Symbol* signature,
2020 OverpassLookupMode overpass_mode,
2021 StaticLookupMode static_mode,
2022 PrivateLookupMode private_mode) const {
2023 return InstanceKlass::find_method_impl(methods(),
2024 name,
2025 signature,
2026 overpass_mode,
2027 static_mode,
2028 private_mode);
2029 }
2030
2031 // find_instance_method looks up the name/signature in the local methods array
2032 // and skips over static methods
2033 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2034 const Symbol* name,
2035 const Symbol* signature,
2036 PrivateLookupMode private_mode) {
2037 Method* const meth = InstanceKlass::find_method_impl(methods,
2038 name,
2039 signature,
2040 OverpassLookupMode::find,
2041 StaticLookupMode::skip,
2042 private_mode);
2043 assert(((meth == nullptr) || !meth->is_static()),
2044 "find_instance_method should have skipped statics");
2045 return meth;
2046 }
2047
2048 // find_instance_method looks up the name/signature in the local methods array
2049 // and skips over static methods
2050 Method* InstanceKlass::find_instance_method(const Symbol* name,
2051 const Symbol* signature,
2052 PrivateLookupMode private_mode) const {
2053 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2054 }
2055
2056 // Find looks up the name/signature in the local methods array
2057 // and filters on the overpass, static and private flags
2058 // This returns the first one found
2059 // note that the local methods array can have up to one overpass, one static
2060 // and one instance (private or not) with the same name/signature
2061 Method* InstanceKlass::find_local_method(const Symbol* name,
2062 const Symbol* signature,
2063 OverpassLookupMode overpass_mode,
2064 StaticLookupMode static_mode,
2065 PrivateLookupMode private_mode) const {
2066 return InstanceKlass::find_method_impl(methods(),
2067 name,
2068 signature,
2069 overpass_mode,
2070 static_mode,
2071 private_mode);
2072 }
2073
2074 // Find looks up the name/signature in the local methods array
2075 // and filters on the overpass, static and private flags
2076 // This returns the first one found
2077 // note that the local methods array can have up to one overpass, one static
2078 // and one instance (private or not) with the same name/signature
2079 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2080 const Symbol* name,
2081 const Symbol* signature,
2082 OverpassLookupMode overpass_mode,
2083 StaticLookupMode static_mode,
2084 PrivateLookupMode private_mode) {
2085 return InstanceKlass::find_method_impl(methods,
2086 name,
2087 signature,
2088 overpass_mode,
2089 static_mode,
2090 private_mode);
2091 }
2092
2093 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2094 const Symbol* name,
2095 const Symbol* signature) {
2096 return InstanceKlass::find_method_impl(methods,
2097 name,
2098 signature,
2099 OverpassLookupMode::find,
2100 StaticLookupMode::find,
2101 PrivateLookupMode::find);
2102 }
2103
2104 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2105 const Symbol* name,
2106 const Symbol* signature,
2107 OverpassLookupMode overpass_mode,
2108 StaticLookupMode static_mode,
2109 PrivateLookupMode private_mode) {
2110 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2111 return hit >= 0 ? methods->at(hit): nullptr;
2112 }
2113
2114 // true if method matches signature and conforms to skipping_X conditions.
2115 static bool method_matches(const Method* m,
2116 const Symbol* signature,
2117 bool skipping_overpass,
2118 bool skipping_static,
2119 bool skipping_private) {
2120 return ((m->signature() == signature) &&
2121 (!skipping_overpass || !m->is_overpass()) &&
2122 (!skipping_static || !m->is_static()) &&
2123 (!skipping_private || !m->is_private()));
2124 }
2125
2126 // Used directly for default_methods to find the index into the
2127 // default_vtable_indices, and indirectly by find_method
2128 // find_method_index looks in the local methods array to return the index
2129 // of the matching name/signature. If, overpass methods are being ignored,
2130 // the search continues to find a potential non-overpass match. This capability
2131 // is important during method resolution to prefer a static method, for example,
2132 // over an overpass method.
2133 // There is the possibility in any _method's array to have the same name/signature
2134 // for a static method, an overpass method and a local instance method
2135 // To correctly catch a given method, the search criteria may need
2136 // to explicitly skip the other two. For local instance methods, it
2137 // is often necessary to skip private methods
2138 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2139 const Symbol* name,
2140 const Symbol* signature,
2141 OverpassLookupMode overpass_mode,
2142 StaticLookupMode static_mode,
2143 PrivateLookupMode private_mode) {
2144 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2145 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2146 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2147 const int hit = quick_search(methods, name);
2148 if (hit != -1) {
2149 const Method* const m = methods->at(hit);
2150
2151 // Do linear search to find matching signature. First, quick check
2152 // for common case, ignoring overpasses if requested.
2153 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2154 return hit;
2155 }
2156
2157 // search downwards through overloaded methods
2158 int i;
2159 for (i = hit - 1; i >= 0; --i) {
2160 const Method* const m = methods->at(i);
2161 assert(m->is_method(), "must be method");
2162 if (m->name() != name) {
2163 break;
2164 }
2165 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2166 return i;
2167 }
2168 }
2169 // search upwards
2170 for (i = hit + 1; i < methods->length(); ++i) {
2171 const Method* const m = methods->at(i);
2172 assert(m->is_method(), "must be method");
2173 if (m->name() != name) {
2174 break;
2175 }
2176 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2177 return i;
2178 }
2179 }
2180 // not found
2181 #ifdef ASSERT
2182 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2183 linear_search(methods, name, signature);
2184 assert(-1 == index, "binary search should have found entry %d", index);
2185 #endif
2186 }
2187 return -1;
2188 }
2189
2190 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2191 return find_method_by_name(methods(), name, end);
2192 }
2193
2194 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2195 const Symbol* name,
2196 int* end_ptr) {
2197 assert(end_ptr != nullptr, "just checking");
2198 int start = quick_search(methods, name);
2199 int end = start + 1;
2200 if (start != -1) {
2201 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2202 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2203 *end_ptr = end;
2204 return start;
2205 }
2206 return -1;
2207 }
2208
2209 // uncached_lookup_method searches both the local class methods array and all
2210 // superclasses methods arrays, skipping any overpass methods in superclasses,
2211 // and possibly skipping private methods.
2212 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2213 const Symbol* signature,
2214 OverpassLookupMode overpass_mode,
2215 PrivateLookupMode private_mode) const {
2216 OverpassLookupMode overpass_local_mode = overpass_mode;
2217 const Klass* klass = this;
2218 while (klass != nullptr) {
2219 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2220 signature,
2221 overpass_local_mode,
2222 StaticLookupMode::find,
2223 private_mode);
2224 if (method != nullptr) {
2225 return method;
2226 }
2227 klass = klass->super();
2228 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2229 }
2230 return nullptr;
2231 }
2232
2233 #ifdef ASSERT
2234 // search through class hierarchy and return true if this class or
2235 // one of the superclasses was redefined
2236 bool InstanceKlass::has_redefined_this_or_super() const {
2237 const Klass* klass = this;
2238 while (klass != nullptr) {
2239 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2240 return true;
2241 }
2242 klass = klass->super();
2243 }
2244 return false;
2245 }
2246 #endif
2247
2248 // lookup a method in the default methods list then in all transitive interfaces
2249 // Do NOT return private or static methods
2250 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2251 Symbol* signature) const {
2252 Method* m = nullptr;
2253 if (default_methods() != nullptr) {
2254 m = find_method(default_methods(), name, signature);
2255 }
2256 // Look up interfaces
2257 if (m == nullptr) {
2258 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2259 }
2260 return m;
2261 }
2262
2263 // lookup a method in all the interfaces that this class implements
2264 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2265 // They should only be found in the initial InterfaceMethodRef
2266 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2267 Symbol* signature,
2268 DefaultsLookupMode defaults_mode) const {
2269 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2270 int num_ifs = all_ifs->length();
2271 InstanceKlass *ik = nullptr;
2272 for (int i = 0; i < num_ifs; i++) {
2273 ik = all_ifs->at(i);
2274 Method* m = ik->lookup_method(name, signature);
2275 if (m != nullptr && m->is_public() && !m->is_static() &&
2276 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2277 return m;
2278 }
2279 }
2280 return nullptr;
2281 }
2282
2283 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2284 :_st(st), _verbose(verbose) {
2285 ResourceMark rm;
2286 _st->print("%-18s ", "KlassAddr");
2287 _st->print("%-4s ", "Size");
2288 _st->print("%-20s ", "State");
2289 _st->print("%-7s ", "Flags");
2290 _st->print("%-5s ", "ClassName");
2291 _st->cr();
2292 }
2293
2294 void PrintClassClosure::do_klass(Klass* k) {
2295 ResourceMark rm;
2296 // klass pointer
2297 _st->print(PTR_FORMAT " ", p2i(k));
2298 // klass size
2299 _st->print("%4d ", k->size());
2300 // initialization state
2301 if (k->is_instance_klass()) {
2302 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2303 } else {
2304 _st->print("%-20s ","");
2305 }
2306 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2307 char buf[10];
2308 int i = 0;
2309 if (k->has_finalizer()) buf[i++] = 'F';
2310 if (k->is_instance_klass()) {
2311 InstanceKlass* ik = InstanceKlass::cast(k);
2312 if (ik->has_final_method()) buf[i++] = 'f';
2313 if (ik->is_rewritten()) buf[i++] = 'W';
2314 if (ik->is_contended()) buf[i++] = 'C';
2315 if (ik->has_been_redefined()) buf[i++] = 'R';
2316 if (ik->is_shared()) buf[i++] = 'S';
2317 }
2318 buf[i++] = '\0';
2319 _st->print("%-7s ", buf);
2320 // klass name
2321 _st->print("%-5s ", k->external_name());
2322 // end
2323 _st->cr();
2324 if (_verbose) {
2325 k->print_on(_st);
2326 }
2327 }
2328
2329 /* jni_id_for for jfieldIds only */
2330 JNIid* InstanceKlass::jni_id_for(int offset) {
2331 MutexLocker ml(JfieldIdCreation_lock);
2332 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2333 if (probe == nullptr) {
2334 // Allocate new static field identifier
2335 probe = new JNIid(this, offset, jni_ids());
2336 set_jni_ids(probe);
2337 }
2338 return probe;
2339 }
2340
2341 u2 InstanceKlass::enclosing_method_data(int offset) const {
2342 const Array<jushort>* const inner_class_list = inner_classes();
2343 if (inner_class_list == nullptr) {
2344 return 0;
2345 }
2346 const int length = inner_class_list->length();
2347 if (length % inner_class_next_offset == 0) {
2348 return 0;
2349 }
2350 const int index = length - enclosing_method_attribute_size;
2351 assert(offset < enclosing_method_attribute_size, "invalid offset");
2352 return inner_class_list->at(index + offset);
2353 }
2354
2355 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2356 u2 method_index) {
2357 Array<jushort>* inner_class_list = inner_classes();
2358 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2359 int length = inner_class_list->length();
2360 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2361 int index = length - enclosing_method_attribute_size;
2362 inner_class_list->at_put(
2363 index + enclosing_method_class_index_offset, class_index);
2364 inner_class_list->at_put(
2365 index + enclosing_method_method_index_offset, method_index);
2366 }
2367 }
2368
2369 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2370 if (method->is_old() && !method->is_obsolete()) {
2371 // If the method passed in is old (but not obsolete), use the current version.
2372 method = method_with_idnum((int)idnum);
2373 assert(method != nullptr, "old and but not obsolete, so should exist");
2374 }
2375 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2376 Atomic::release_store(&jmeths[idnum + 1], new_id);
2377 return new_id;
2378 }
2379
2380 // Lookup or create a jmethodID.
2381 // This code is called by the VMThread and JavaThreads so the
2382 // locking has to be done very carefully to avoid deadlocks
2383 // and/or other cache consistency problems.
2384 //
2385 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2386 Method* method = method_h();
2387 int idnum = method->method_idnum();
2388 jmethodID* jmeths = methods_jmethod_ids_acquire();
2389
2390 // We use a double-check locking idiom here because this cache is
2391 // performance sensitive. In the normal system, this cache only
2392 // transitions from null to non-null which is safe because we use
2393 // release_set_methods_jmethod_ids() to advertise the new cache.
2394 // A partially constructed cache should never be seen by a racing
2395 // thread. We also use release_store() to save a new jmethodID
2396 // in the cache so a partially constructed jmethodID should never be
2397 // seen either. Cache reads of existing jmethodIDs proceed without a
2398 // lock, but cache writes of a new jmethodID requires uniqueness and
2399 // creation of the cache itself requires no leaks so a lock is
2400 // acquired in those two cases.
2401 //
2402 // If the RedefineClasses() API has been used, then this cache grows
2403 // in the redefinition safepoint.
2404
2405 if (jmeths == nullptr) {
2406 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2407 jmeths = methods_jmethod_ids_acquire();
2408 // Still null?
2409 if (jmeths == nullptr) {
2410 size_t size = idnum_allocated_count();
2411 assert(size > (size_t)idnum, "should already have space");
2412 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2413 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2414 // cache size is stored in element[0], other elements offset by one
2415 jmeths[0] = (jmethodID)size;
2416 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2417
2418 // publish jmeths
2419 release_set_methods_jmethod_ids(jmeths);
2420 return new_id;
2421 }
2422 }
2423
2424 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2425 if (id == nullptr) {
2426 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2427 id = jmeths[idnum + 1];
2428 // Still null?
2429 if (id == nullptr) {
2430 return update_jmethod_id(jmeths, method, idnum);
2431 }
2432 }
2433 return id;
2434 }
2435
2436 void InstanceKlass::update_methods_jmethod_cache() {
2437 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2438 jmethodID* cache = _methods_jmethod_ids;
2439 if (cache != nullptr) {
2440 size_t size = idnum_allocated_count();
2441 size_t old_size = (size_t)cache[0];
2442 if (old_size < size + 1) {
2443 // Allocate a larger one and copy entries to the new one.
2444 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2445 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2446 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2447 // The cache size is stored in element[0]; the other elements are offset by one.
2448 new_cache[0] = (jmethodID)size;
2449
2450 for (int i = 1; i <= (int)old_size; i++) {
2451 new_cache[i] = cache[i];
2452 }
2453 _methods_jmethod_ids = new_cache;
2454 FREE_C_HEAP_ARRAY(jmethodID, cache);
2455 }
2456 }
2457 }
2458
2459 // Figure out how many jmethodIDs haven't been allocated, and make
2460 // sure space for them is pre-allocated. This makes getting all
2461 // method ids much, much faster with classes with more than 8
2462 // methods, and has a *substantial* effect on performance with jvmti
2463 // code that loads all jmethodIDs for all classes.
2464 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2465 int new_jmeths = 0;
2466 int length = methods()->length();
2467 for (int index = start_offset; index < length; index++) {
2468 Method* m = methods()->at(index);
2469 jmethodID id = m->find_jmethod_id_or_null();
2470 if (id == nullptr) {
2471 new_jmeths++;
2472 }
2473 }
2474 if (new_jmeths != 0) {
2475 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2476 }
2477 }
2478
2479 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2480 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2481 int idnum = method->method_idnum();
2482 jmethodID* jmeths = methods_jmethod_ids_acquire();
2483 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2484 }
2485
2486 inline DependencyContext InstanceKlass::dependencies() {
2487 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2488 return dep_context;
2489 }
2490
2491 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2492 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2493 }
2494
2495 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2496 dependencies().add_dependent_nmethod(nm);
2497 }
2498
2499 void InstanceKlass::clean_dependency_context() {
2500 dependencies().clean_unloading_dependents();
2501 }
2502
2503 #ifndef PRODUCT
2504 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2505 dependencies().print_dependent_nmethods(verbose);
2506 }
2507
2508 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2509 return dependencies().is_dependent_nmethod(nm);
2510 }
2511 #endif //PRODUCT
2512
2513 void InstanceKlass::clean_weak_instanceklass_links() {
2514 clean_implementors_list();
2515 clean_method_data();
2516 }
2517
2518 void InstanceKlass::clean_implementors_list() {
2519 assert(is_loader_alive(), "this klass should be live");
2520 if (is_interface()) {
2521 assert (ClassUnloading, "only called for ClassUnloading");
2522 for (;;) {
2523 // Use load_acquire due to competing with inserts
2524 InstanceKlass* volatile* iklass = adr_implementor();
2525 assert(iklass != nullptr, "Klass must not be null");
2526 InstanceKlass* impl = Atomic::load_acquire(iklass);
2527 if (impl != nullptr && !impl->is_loader_alive()) {
2528 // null this field, might be an unloaded instance klass or null
2529 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2530 // Successfully unlinking implementor.
2531 if (log_is_enabled(Trace, class, unload)) {
2532 ResourceMark rm;
2533 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2534 }
2535 return;
2536 }
2537 } else {
2538 return;
2539 }
2540 }
2541 }
2542 }
2543
2544 void InstanceKlass::clean_method_data() {
2545 for (int m = 0; m < methods()->length(); m++) {
2546 MethodData* mdo = methods()->at(m)->method_data();
2547 if (mdo != nullptr) {
2548 mdo->clean_method_data(/*always_clean*/false);
2549 }
2550 }
2551 }
2552
2553 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2554 Klass::metaspace_pointers_do(it);
2555
2556 if (log_is_enabled(Trace, cds)) {
2557 ResourceMark rm;
2558 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2559 }
2560
2561 it->push(&_annotations);
2562 it->push((Klass**)&_array_klasses);
2563 if (!is_rewritten()) {
2564 it->push(&_constants, MetaspaceClosure::_writable);
2565 } else {
2566 it->push(&_constants);
2567 }
2568 it->push(&_inner_classes);
2569 #if INCLUDE_JVMTI
2570 it->push(&_previous_versions);
2571 #endif
2572 #if INCLUDE_CDS
2573 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2574 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2575 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2576 // The length check on the _methods is necessary because classes which don't have any
2577 // methods share the Universe::_the_empty_method_array which is in the RO region.
2578 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2579 // To handle jsr bytecode, new Method* maybe stored into _methods
2580 it->push(&_methods, MetaspaceClosure::_writable);
2581 } else {
2582 #endif
2583 it->push(&_methods);
2584 #if INCLUDE_CDS
2585 }
2586 #endif
2587 it->push(&_default_methods);
2588 it->push(&_local_interfaces);
2589 it->push(&_transitive_interfaces);
2590 it->push(&_method_ordering);
2591 if (!is_rewritten()) {
2592 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2593 } else {
2594 it->push(&_default_vtable_indices);
2595 }
2596
2597 it->push(&_fieldinfo_stream);
2598 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2599 it->push(&_fields_status, MetaspaceClosure::_writable);
2600
2601 if (itable_length() > 0) {
2602 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2603 int method_table_offset_in_words = ioe->offset()/wordSize;
2604 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2605
2606 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2607 / itableOffsetEntry::size();
2608
2609 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2610 if (ioe->interface_klass() != nullptr) {
2611 it->push(ioe->interface_klass_addr());
2612 itableMethodEntry* ime = ioe->first_method_entry(this);
2613 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2614 for (int index = 0; index < n; index ++) {
2615 it->push(ime[index].method_addr());
2616 }
2617 }
2618 }
2619 }
2620
2621 it->push(&_nest_host);
2622 it->push(&_nest_members);
2623 it->push(&_permitted_subclasses);
2624 it->push(&_record_components);
2625 }
2626
2627 #if INCLUDE_CDS
2628 void InstanceKlass::remove_unshareable_info() {
2629
2630 if (is_linked()) {
2631 assert(can_be_verified_at_dumptime(), "must be");
2632 // Remember this so we can avoid walking the hierarchy at runtime.
2633 set_verified_at_dump_time();
2634 }
2635
2636 Klass::remove_unshareable_info();
2637
2638 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2639 // Classes are attempted to link during dumping and may fail,
2640 // but these classes are still in the dictionary and class list in CLD.
2641 // If the class has failed verification, there is nothing else to remove.
2642 return;
2643 }
2644
2645 // Reset to the 'allocated' state to prevent any premature accessing to
2646 // a shared class at runtime while the class is still being loaded and
2647 // restored. A class' init_state is set to 'loaded' at runtime when it's
2648 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2649 _init_state = allocated;
2650
2651 { // Otherwise this needs to take out the Compile_lock.
2652 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2653 init_implementor();
2654 }
2655
2656 // Call remove_unshareable_info() on other objects that belong to this class, except
2657 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2658 // ArchiveBuilder::make_klasses_shareable(),
2659
2660 for (int i = 0; i < methods()->length(); i++) {
2661 Method* m = methods()->at(i);
2662 m->remove_unshareable_info();
2663 }
2664
2665 // do array classes also.
2666 if (array_klasses() != nullptr) {
2667 array_klasses()->remove_unshareable_info();
2668 }
2669
2670 // These are not allocated from metaspace. They are safe to set to null.
2671 _source_debug_extension = nullptr;
2672 _dep_context = nullptr;
2673 _osr_nmethods_head = nullptr;
2674 #if INCLUDE_JVMTI
2675 _breakpoints = nullptr;
2676 _previous_versions = nullptr;
2677 _cached_class_file = nullptr;
2678 _jvmti_cached_class_field_map = nullptr;
2679 #endif
2680
2681 _init_thread = nullptr;
2682 _methods_jmethod_ids = nullptr;
2683 _jni_ids = nullptr;
2684 _oop_map_cache = nullptr;
2685 if (CDSConfig::is_dumping_invokedynamic() && HeapShared::is_lambda_proxy_klass(this)) {
2686 // keep _nest_host
2687 } else {
2688 // clear _nest_host to ensure re-load at runtime
2689 _nest_host = nullptr;
2690 }
2691 init_shared_package_entry();
2692 _dep_context_last_cleaned = 0;
2693
2694 remove_unshareable_flags();
2695 }
2696
2697 void InstanceKlass::remove_unshareable_flags() {
2698 // clear all the flags/stats that shouldn't be in the archived version
2699 assert(!is_scratch_class(), "must be");
2700 assert(!has_been_redefined(), "must be");
2701 #if INCLUDE_JVMTI
2702 set_is_being_redefined(false);
2703 #endif
2704 set_has_resolved_methods(false);
2705 }
2706
2707 void InstanceKlass::remove_java_mirror() {
2708 Klass::remove_java_mirror();
2709
2710 // do array classes also.
2711 if (array_klasses() != nullptr) {
2712 array_klasses()->remove_java_mirror();
2713 }
2714 }
2715
2716 void InstanceKlass::init_shared_package_entry() {
2717 assert(CDSConfig::is_dumping_archive(), "must be");
2718 #if !INCLUDE_CDS_JAVA_HEAP
2719 _package_entry = nullptr;
2720 #else
2721 if (CDSConfig::is_dumping_full_module_graph()) {
2722 if (is_shared_unregistered_class()) {
2723 _package_entry = nullptr;
2724 } else {
2725 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2726 }
2727 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2728 CDSConfig::is_using_full_module_graph() &&
2729 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2730 // _package_entry is an archived package in the base archive. Leave it as is.
2731 } else {
2732 _package_entry = nullptr;
2733 }
2734 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2735 #endif
2736 }
2737
2738 void InstanceKlass::compute_has_loops_flag_for_methods() {
2739 Array<Method*>* methods = this->methods();
2740 for (int index = 0; index < methods->length(); ++index) {
2741 Method* m = methods->at(index);
2742 if (!m->is_overpass()) { // work around JDK-8305771
2743 m->compute_has_loops_flag();
2744 }
2745 }
2746 }
2747
2748 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2749 PackageEntry* pkg_entry, TRAPS) {
2750 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2751 // before the InstanceKlass is added to the SystemDictionary. Make
2752 // sure the current state is <loaded.
2753 assert(!is_loaded(), "invalid init state");
2754 assert(!shared_loading_failed(), "Must not try to load failed class again");
2755 set_package(loader_data, pkg_entry, CHECK);
2756 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2757
2758 Array<Method*>* methods = this->methods();
2759 int num_methods = methods->length();
2760 for (int index = 0; index < num_methods; ++index) {
2761 methods->at(index)->restore_unshareable_info(CHECK);
2762 }
2763 #if INCLUDE_JVMTI
2764 if (JvmtiExport::has_redefined_a_class()) {
2765 // Reinitialize vtable because RedefineClasses may have changed some
2766 // entries in this vtable for super classes so the CDS vtable might
2767 // point to old or obsolete entries. RedefineClasses doesn't fix up
2768 // vtables in the shared system dictionary, only the main one.
2769 // It also redefines the itable too so fix that too.
2770 // First fix any default methods that point to a super class that may
2771 // have been redefined.
2772 bool trace_name_printed = false;
2773 adjust_default_methods(&trace_name_printed);
2774 if (verified_at_dump_time()) {
2775 // Initialize vtable and itable for classes which can be verified at dump time.
2776 // Unlinked classes such as old classes with major version < 50 cannot be verified
2777 // at dump time.
2778 vtable().initialize_vtable();
2779 itable().initialize_itable();
2780 }
2781 }
2782 #endif // INCLUDE_JVMTI
2783
2784 // restore constant pool resolved references
2785 constants()->restore_unshareable_info(CHECK);
2786
2787 if (array_klasses() != nullptr) {
2788 // To get a consistent list of classes we need MultiArray_lock to ensure
2789 // array classes aren't observed while they are being restored.
2790 RecursiveLocker rl(MultiArray_lock, THREAD);
2791 assert(this == array_klasses()->bottom_klass(), "sanity");
2792 // Array classes have null protection domain.
2793 // --> see ArrayKlass::complete_create_array_klass()
2794 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2795 }
2796
2797 // Initialize @ValueBased class annotation if not already set in the archived klass.
2798 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2799 set_is_value_based();
2800 }
2801 }
2802
2803 // Check if a class or any of its supertypes has a version older than 50.
2804 // CDS will not perform verification of old classes during dump time because
2805 // without changing the old verifier, the verification constraint cannot be
2806 // retrieved during dump time.
2807 // Verification of archived old classes will be performed during run time.
2808 bool InstanceKlass::can_be_verified_at_dumptime() const {
2809 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2810 // This is a class that was dumped into the base archive, so we know
2811 // it was verified at dump time.
2812 return true;
2813 }
2814 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2815 return false;
2816 }
2817 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2818 return false;
2819 }
2820 Array<InstanceKlass*>* interfaces = local_interfaces();
2821 int len = interfaces->length();
2822 for (int i = 0; i < len; i++) {
2823 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2824 return false;
2825 }
2826 }
2827 return true;
2828 }
2829
2830 int InstanceKlass::shared_class_loader_type() const {
2831 if (is_shared_boot_class()) {
2832 return ClassLoader::BOOT_LOADER;
2833 } else if (is_shared_platform_class()) {
2834 return ClassLoader::PLATFORM_LOADER;
2835 } else if (is_shared_app_class()) {
2836 return ClassLoader::APP_LOADER;
2837 } else {
2838 return ClassLoader::OTHER;
2839 }
2840 }
2841 #endif // INCLUDE_CDS
2842
2843 #if INCLUDE_JVMTI
2844 static void clear_all_breakpoints(Method* m) {
2845 m->clear_all_breakpoints();
2846 }
2847 #endif
2848
2849 void InstanceKlass::unload_class(InstanceKlass* ik) {
2850
2851 if (ik->is_scratch_class()) {
2852 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2853 return;
2854 }
2855 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2856
2857 // Release dependencies.
2858 ik->dependencies().remove_all_dependents();
2859
2860 // notify the debugger
2861 if (JvmtiExport::should_post_class_unload()) {
2862 JvmtiExport::post_class_unload(ik);
2863 }
2864
2865 // notify ClassLoadingService of class unload
2866 ClassLoadingService::notify_class_unloaded(ik);
2867
2868 SystemDictionaryShared::handle_class_unloading(ik);
2869
2870 if (log_is_enabled(Info, class, unload)) {
2871 ResourceMark rm;
2872 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2873 }
2874
2875 Events::log_class_unloading(Thread::current(), ik);
2876
2877 #if INCLUDE_JFR
2878 assert(ik != nullptr, "invariant");
2879 EventClassUnload event;
2880 event.set_unloadedClass(ik);
2881 event.set_definingClassLoader(ik->class_loader_data());
2882 event.commit();
2883 #endif
2884 }
2885
2886 static void method_release_C_heap_structures(Method* m) {
2887 m->release_C_heap_structures();
2888 }
2889
2890 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2891 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2892 // Clean up C heap
2893 Klass::release_C_heap_structures();
2894
2895 // Deallocate and call destructors for MDO mutexes
2896 if (release_sub_metadata) {
2897 methods_do(method_release_C_heap_structures);
2898 }
2899
2900 // Deallocate oop map cache
2901 if (_oop_map_cache != nullptr) {
2902 delete _oop_map_cache;
2903 _oop_map_cache = nullptr;
2904 }
2905
2906 // Deallocate JNI identifiers for jfieldIDs
2907 JNIid::deallocate(jni_ids());
2908 set_jni_ids(nullptr);
2909
2910 jmethodID* jmeths = methods_jmethod_ids_acquire();
2911 if (jmeths != nullptr) {
2912 release_set_methods_jmethod_ids(nullptr);
2913 FreeHeap(jmeths);
2914 }
2915
2916 assert(_dep_context == nullptr,
2917 "dependencies should already be cleaned");
2918
2919 #if INCLUDE_JVMTI
2920 // Deallocate breakpoint records
2921 if (breakpoints() != nullptr) {
2922 methods_do(clear_all_breakpoints);
2923 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2924 }
2925
2926 // deallocate the cached class file
2927 if (_cached_class_file != nullptr) {
2928 os::free(_cached_class_file);
2929 _cached_class_file = nullptr;
2930 }
2931 #endif
2932
2933 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2934
2935 if (release_sub_metadata) {
2936 constants()->release_C_heap_structures();
2937 }
2938 }
2939
2940 // The constant pool is on stack if any of the methods are executing or
2941 // referenced by handles.
2942 bool InstanceKlass::on_stack() const {
2943 return _constants->on_stack();
2944 }
2945
2946 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
2947 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
2948 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
2949
2950 // minor and major version numbers of class file
2951 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
2952 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
2953 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
2954 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
2955
2956 InstanceKlass* InstanceKlass::get_klass_version(int version) {
2957 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
2958 if (ik->constants()->version() == version) {
2959 return ik;
2960 }
2961 }
2962 return nullptr;
2963 }
2964
2965 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2966 if (array == nullptr) {
2967 _source_debug_extension = nullptr;
2968 } else {
2969 // Adding one to the attribute length in order to store a null terminator
2970 // character could cause an overflow because the attribute length is
2971 // already coded with an u4 in the classfile, but in practice, it's
2972 // unlikely to happen.
2973 assert((length+1) > length, "Overflow checking");
2974 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2975 for (int i = 0; i < length; i++) {
2976 sde[i] = array[i];
2977 }
2978 sde[length] = '\0';
2979 _source_debug_extension = sde;
2980 }
2981 }
2982
2983 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
2984 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
2985 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
2986
2987 const char* InstanceKlass::signature_name() const {
2988
2989 // Get the internal name as a c string
2990 const char* src = (const char*) (name()->as_C_string());
2991 const int src_length = (int)strlen(src);
2992
2993 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
2994
2995 // Add L as type indicator
2996 int dest_index = 0;
2997 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2998
2999 // Add the actual class name
3000 for (int src_index = 0; src_index < src_length; ) {
3001 dest[dest_index++] = src[src_index++];
3002 }
3003
3004 if (is_hidden()) { // Replace the last '+' with a '.'.
3005 for (int index = (int)src_length; index > 0; index--) {
3006 if (dest[index] == '+') {
3007 dest[index] = JVM_SIGNATURE_DOT;
3008 break;
3009 }
3010 }
3011 }
3012
3013 // Add the semicolon and the null
3014 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3015 dest[dest_index] = '\0';
3016 return dest;
3017 }
3018
3019 ModuleEntry* InstanceKlass::module() const {
3020 if (is_hidden() &&
3021 in_unnamed_package() &&
3022 class_loader_data()->has_class_mirror_holder()) {
3023 // For a non-strong hidden class defined to an unnamed package,
3024 // its (class held) CLD will not have an unnamed module created for it.
3025 // Two choices to find the correct ModuleEntry:
3026 // 1. If hidden class is within a nest, use nest host's module
3027 // 2. Find the unnamed module off from the class loader
3028 // For now option #2 is used since a nest host is not set until
3029 // after the instance class is created in jvm_lookup_define_class().
3030 if (class_loader_data()->is_boot_class_loader_data()) {
3031 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3032 } else {
3033 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3034 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3035 return java_lang_Module::module_entry(module);
3036 }
3037 }
3038
3039 // Class is in a named package
3040 if (!in_unnamed_package()) {
3041 return _package_entry->module();
3042 }
3043
3044 // Class is in an unnamed package, return its loader's unnamed module
3045 return class_loader_data()->unnamed_module();
3046 }
3047
3048 bool InstanceKlass::in_javabase_module() const {
3049 return module()->name() == vmSymbols::java_base();
3050 }
3051
3052 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3053
3054 // ensure java/ packages only loaded by boot or platform builtin loaders
3055 // not needed for shared class since CDS does not archive prohibited classes.
3056 if (!is_shared()) {
3057 check_prohibited_package(name(), loader_data, CHECK);
3058 }
3059
3060 if (is_shared() && _package_entry != nullptr) {
3061 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3062 // we can use the saved package
3063 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3064 return;
3065 } else {
3066 _package_entry = nullptr;
3067 }
3068 }
3069
3070 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3071 // it returns, so we need to decrement it when the current function exits.
3072 TempNewSymbol from_class_name =
3073 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3074
3075 Symbol* pkg_name;
3076 if (pkg_entry != nullptr) {
3077 pkg_name = pkg_entry->name();
3078 } else {
3079 pkg_name = from_class_name;
3080 }
3081
3082 if (pkg_name != nullptr && loader_data != nullptr) {
3083
3084 // Find in class loader's package entry table.
3085 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3086
3087 // If the package name is not found in the loader's package
3088 // entry table, it is an indication that the package has not
3089 // been defined. Consider it defined within the unnamed module.
3090 if (_package_entry == nullptr) {
3091
3092 if (!ModuleEntryTable::javabase_defined()) {
3093 // Before java.base is defined during bootstrapping, define all packages in
3094 // the java.base module. If a non-java.base package is erroneously placed
3095 // in the java.base module it will be caught later when java.base
3096 // is defined by ModuleEntryTable::verify_javabase_packages check.
3097 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3098 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3099 } else {
3100 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3101 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3102 }
3103
3104 // A package should have been successfully created
3105 DEBUG_ONLY(ResourceMark rm(THREAD));
3106 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3107 name()->as_C_string(), loader_data->loader_name_and_id());
3108 }
3109
3110 if (log_is_enabled(Debug, module)) {
3111 ResourceMark rm(THREAD);
3112 ModuleEntry* m = _package_entry->module();
3113 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3114 external_name(),
3115 pkg_name->as_C_string(),
3116 loader_data->loader_name_and_id(),
3117 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3118 }
3119 } else {
3120 ResourceMark rm(THREAD);
3121 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3122 external_name(),
3123 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3124 UNNAMED_MODULE);
3125 }
3126 }
3127
3128 // Function set_classpath_index ensures that for a non-null _package_entry
3129 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3130 // It then sets the classpath_index in the package entry record.
3131 //
3132 // The classpath_index field is used to find the entry on the boot loader class
3133 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3134 // in an unnamed module. It is also used to indicate (for all packages whose
3135 // classes are loaded by the boot loader) that at least one of the package's
3136 // classes has been loaded.
3137 void InstanceKlass::set_classpath_index(s2 path_index) {
3138 if (_package_entry != nullptr) {
3139 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3140 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3141 assert(path_index != -1, "Unexpected classpath_index");
3142 _package_entry->set_classpath_index(path_index);
3143 }
3144 }
3145
3146 // different versions of is_same_class_package
3147
3148 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3149 oop classloader1 = this->class_loader();
3150 PackageEntry* classpkg1 = this->package();
3151 if (class2->is_objArray_klass()) {
3152 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3153 }
3154
3155 oop classloader2;
3156 PackageEntry* classpkg2;
3157 if (class2->is_instance_klass()) {
3158 classloader2 = class2->class_loader();
3159 classpkg2 = class2->package();
3160 } else {
3161 assert(class2->is_typeArray_klass(), "should be type array");
3162 classloader2 = nullptr;
3163 classpkg2 = nullptr;
3164 }
3165
3166 // Same package is determined by comparing class loader
3167 // and package entries. Both must be the same. This rule
3168 // applies even to classes that are defined in the unnamed
3169 // package, they still must have the same class loader.
3170 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3171 return true;
3172 }
3173
3174 return false;
3175 }
3176
3177 // return true if this class and other_class are in the same package. Classloader
3178 // and classname information is enough to determine a class's package
3179 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3180 const Symbol* other_class_name) const {
3181 if (class_loader() != other_class_loader) {
3182 return false;
3183 }
3184 if (name()->fast_compare(other_class_name) == 0) {
3185 return true;
3186 }
3187
3188 {
3189 ResourceMark rm;
3190
3191 bool bad_class_name = false;
3192 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3193 if (bad_class_name) {
3194 return false;
3195 }
3196 // Check that package_from_class_name() returns null, not "", if there is no package.
3197 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3198
3199 const Symbol* const this_package_name =
3200 this->package() != nullptr ? this->package()->name() : nullptr;
3201
3202 if (this_package_name == nullptr || other_pkg == nullptr) {
3203 // One of the two doesn't have a package. Only return true if the other
3204 // one also doesn't have a package.
3205 return this_package_name == other_pkg;
3206 }
3207
3208 // Check if package is identical
3209 return this_package_name->fast_compare(other_pkg) == 0;
3210 }
3211 }
3212
3213 static bool is_prohibited_package_slow(Symbol* class_name) {
3214 // Caller has ResourceMark
3215 int length;
3216 jchar* unicode = class_name->as_unicode(length);
3217 return (length >= 5 &&
3218 unicode[0] == 'j' &&
3219 unicode[1] == 'a' &&
3220 unicode[2] == 'v' &&
3221 unicode[3] == 'a' &&
3222 unicode[4] == '/');
3223 }
3224
3225 // Only boot and platform class loaders can define classes in "java/" packages.
3226 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3227 ClassLoaderData* loader_data,
3228 TRAPS) {
3229 if (!loader_data->is_boot_class_loader_data() &&
3230 !loader_data->is_platform_class_loader_data() &&
3231 class_name != nullptr && class_name->utf8_length() >= 5) {
3232 ResourceMark rm(THREAD);
3233 bool prohibited;
3234 const u1* base = class_name->base();
3235 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3236 prohibited = is_prohibited_package_slow(class_name);
3237 } else {
3238 char* name = class_name->as_C_string();
3239 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3240 }
3241 if (prohibited) {
3242 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3243 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3244 char* name = pkg_name->as_C_string();
3245 const char* class_loader_name = loader_data->loader_name_and_id();
3246 StringUtils::replace_no_expand(name, "/", ".");
3247 const char* msg_text1 = "Class loader (instance of): ";
3248 const char* msg_text2 = " tried to load prohibited package name: ";
3249 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3250 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3251 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3252 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3253 }
3254 }
3255 return;
3256 }
3257
3258 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3259 constantPoolHandle i_cp(THREAD, constants());
3260 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3261 int ioff = iter.inner_class_info_index();
3262 if (ioff != 0) {
3263 // Check to see if the name matches the class we're looking for
3264 // before attempting to find the class.
3265 if (i_cp->klass_name_at_matches(this, ioff)) {
3266 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3267 if (this == inner_klass) {
3268 *ooff = iter.outer_class_info_index();
3269 *noff = iter.inner_name_index();
3270 return true;
3271 }
3272 }
3273 }
3274 }
3275 return false;
3276 }
3277
3278 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3279 InstanceKlass* outer_klass = nullptr;
3280 *inner_is_member = false;
3281 int ooff = 0, noff = 0;
3282 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3283 if (has_inner_classes_attr) {
3284 constantPoolHandle i_cp(THREAD, constants());
3285 if (ooff != 0) {
3286 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3287 if (!ok->is_instance_klass()) {
3288 // If the outer class is not an instance klass then it cannot have
3289 // declared any inner classes.
3290 ResourceMark rm(THREAD);
3291 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3292 Exceptions::fthrow(
3293 THREAD_AND_LOCATION,
3294 vmSymbols::java_lang_IncompatibleClassChangeError(),
3295 "%s and %s disagree on InnerClasses attribute",
3296 ok->external_name(),
3297 external_name());
3298 return nullptr;
3299 }
3300 outer_klass = InstanceKlass::cast(ok);
3301 *inner_is_member = true;
3302 }
3303 if (nullptr == outer_klass) {
3304 // It may be a local class; try for that.
3305 int encl_method_class_idx = enclosing_method_class_index();
3306 if (encl_method_class_idx != 0) {
3307 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3308 outer_klass = InstanceKlass::cast(ok);
3309 *inner_is_member = false;
3310 }
3311 }
3312 }
3313
3314 // If no inner class attribute found for this class.
3315 if (nullptr == outer_klass) return nullptr;
3316
3317 // Throws an exception if outer klass has not declared k as an inner klass
3318 // We need evidence that each klass knows about the other, or else
3319 // the system could allow a spoof of an inner class to gain access rights.
3320 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3321 return outer_klass;
3322 }
3323
3324 jint InstanceKlass::compute_modifier_flags() const {
3325 jint access = access_flags().as_int();
3326
3327 // But check if it happens to be member class.
3328 InnerClassesIterator iter(this);
3329 for (; !iter.done(); iter.next()) {
3330 int ioff = iter.inner_class_info_index();
3331 // Inner class attribute can be zero, skip it.
3332 // Strange but true: JVM spec. allows null inner class refs.
3333 if (ioff == 0) continue;
3334
3335 // only look at classes that are already loaded
3336 // since we are looking for the flags for our self.
3337 Symbol* inner_name = constants()->klass_name_at(ioff);
3338 if (name() == inner_name) {
3339 // This is really a member class.
3340 access = iter.inner_access_flags();
3341 break;
3342 }
3343 }
3344 // Remember to strip ACC_SUPER bit
3345 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3346 }
3347
3348 jint InstanceKlass::jvmti_class_status() const {
3349 jint result = 0;
3350
3351 if (is_linked()) {
3352 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3353 }
3354
3355 if (is_initialized()) {
3356 assert(is_linked(), "Class status is not consistent");
3357 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3358 }
3359 if (is_in_error_state()) {
3360 result |= JVMTI_CLASS_STATUS_ERROR;
3361 }
3362 return result;
3363 }
3364
3365 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3366 bool implements_interface; // initialized by method_at_itable_or_null
3367 Method* m = method_at_itable_or_null(holder, index,
3368 implements_interface); // out parameter
3369 if (m != nullptr) {
3370 assert(implements_interface, "sanity");
3371 return m;
3372 } else if (implements_interface) {
3373 // Throw AbstractMethodError since corresponding itable slot is empty.
3374 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3375 } else {
3376 // If the interface isn't implemented by the receiver class,
3377 // the VM should throw IncompatibleClassChangeError.
3378 ResourceMark rm(THREAD);
3379 stringStream ss;
3380 bool same_module = (module() == holder->module());
3381 ss.print("Receiver class %s does not implement "
3382 "the interface %s defining the method to be called "
3383 "(%s%s%s)",
3384 external_name(), holder->external_name(),
3385 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3386 (same_module) ? "" : "; ",
3387 (same_module) ? "" : holder->class_in_module_of_loader());
3388 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3389 }
3390 }
3391
3392 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3393 klassItable itable(this);
3394 for (int i = 0; i < itable.size_offset_table(); i++) {
3395 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3396 if (offset_entry->interface_klass() == holder) {
3397 implements_interface = true;
3398 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3399 Method* m = ime[index].method();
3400 return m;
3401 }
3402 }
3403 implements_interface = false;
3404 return nullptr; // offset entry not found
3405 }
3406
3407 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3408 assert(is_linked(), "required");
3409 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3410 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3411
3412 int vtable_index = Method::invalid_vtable_index;
3413 Symbol* name = intf_method->name();
3414 Symbol* signature = intf_method->signature();
3415
3416 // First check in default method array
3417 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3418 int index = find_method_index(default_methods(),
3419 name, signature,
3420 Klass::OverpassLookupMode::find,
3421 Klass::StaticLookupMode::find,
3422 Klass::PrivateLookupMode::find);
3423 if (index >= 0) {
3424 vtable_index = default_vtable_indices()->at(index);
3425 }
3426 }
3427 if (vtable_index == Method::invalid_vtable_index) {
3428 // get vtable_index for miranda methods
3429 klassVtable vt = vtable();
3430 vtable_index = vt.index_of_miranda(name, signature);
3431 }
3432 return vtable_index;
3433 }
3434
3435 #if INCLUDE_JVMTI
3436 // update default_methods for redefineclasses for methods that are
3437 // not yet in the vtable due to concurrent subclass define and superinterface
3438 // redefinition
3439 // Note: those in the vtable, should have been updated via adjust_method_entries
3440 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3441 // search the default_methods for uses of either obsolete or EMCP methods
3442 if (default_methods() != nullptr) {
3443 for (int index = 0; index < default_methods()->length(); index ++) {
3444 Method* old_method = default_methods()->at(index);
3445 if (old_method == nullptr || !old_method->is_old()) {
3446 continue; // skip uninteresting entries
3447 }
3448 assert(!old_method->is_deleted(), "default methods may not be deleted");
3449 Method* new_method = old_method->get_new_method();
3450 default_methods()->at_put(index, new_method);
3451
3452 if (log_is_enabled(Info, redefine, class, update)) {
3453 ResourceMark rm;
3454 if (!(*trace_name_printed)) {
3455 log_info(redefine, class, update)
3456 ("adjust: klassname=%s default methods from name=%s",
3457 external_name(), old_method->method_holder()->external_name());
3458 *trace_name_printed = true;
3459 }
3460 log_debug(redefine, class, update, vtables)
3461 ("default method update: %s(%s) ",
3462 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3463 }
3464 }
3465 }
3466 }
3467 #endif // INCLUDE_JVMTI
3468
3469 // On-stack replacement stuff
3470 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3471 assert_lock_strong(NMethodState_lock);
3472 #ifndef PRODUCT
3473 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3474 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3475 "redundant OSR recompilation detected. memory leak in CodeCache!");
3476 #endif
3477 // only one compilation can be active
3478 assert(n->is_osr_method(), "wrong kind of nmethod");
3479 n->set_osr_link(osr_nmethods_head());
3480 set_osr_nmethods_head(n);
3481 // Raise the highest osr level if necessary
3482 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3483
3484 // Get rid of the osr methods for the same bci that have lower levels.
3485 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3486 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3487 if (inv != nullptr && inv->is_in_use()) {
3488 inv->make_not_entrant();
3489 }
3490 }
3491 }
3492
3493 // Remove osr nmethod from the list. Return true if found and removed.
3494 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3495 // This is a short non-blocking critical region, so the no safepoint check is ok.
3496 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3497 assert(n->is_osr_method(), "wrong kind of nmethod");
3498 nmethod* last = nullptr;
3499 nmethod* cur = osr_nmethods_head();
3500 int max_level = CompLevel_none; // Find the max comp level excluding n
3501 Method* m = n->method();
3502 // Search for match
3503 bool found = false;
3504 while(cur != nullptr && cur != n) {
3505 if (m == cur->method()) {
3506 // Find max level before n
3507 max_level = MAX2(max_level, cur->comp_level());
3508 }
3509 last = cur;
3510 cur = cur->osr_link();
3511 }
3512 nmethod* next = nullptr;
3513 if (cur == n) {
3514 found = true;
3515 next = cur->osr_link();
3516 if (last == nullptr) {
3517 // Remove first element
3518 set_osr_nmethods_head(next);
3519 } else {
3520 last->set_osr_link(next);
3521 }
3522 }
3523 n->set_osr_link(nullptr);
3524 cur = next;
3525 while (cur != nullptr) {
3526 // Find max level after n
3527 if (m == cur->method()) {
3528 max_level = MAX2(max_level, cur->comp_level());
3529 }
3530 cur = cur->osr_link();
3531 }
3532 m->set_highest_osr_comp_level(max_level);
3533 return found;
3534 }
3535
3536 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3537 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3538 nmethod* osr = osr_nmethods_head();
3539 int found = 0;
3540 while (osr != nullptr) {
3541 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3542 if (osr->method() == m) {
3543 deopt_scope->mark(osr);
3544 found++;
3545 }
3546 osr = osr->osr_link();
3547 }
3548 return found;
3549 }
3550
3551 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3552 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3553 nmethod* osr = osr_nmethods_head();
3554 nmethod* best = nullptr;
3555 while (osr != nullptr) {
3556 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3557 // There can be a time when a c1 osr method exists but we are waiting
3558 // for a c2 version. When c2 completes its osr nmethod we will trash
3559 // the c1 version and only be able to find the c2 version. However
3560 // while we overflow in the c1 code at back branches we don't want to
3561 // try and switch to the same code as we are already running
3562
3563 if (osr->method() == m &&
3564 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3565 if (match_level) {
3566 if (osr->comp_level() == comp_level) {
3567 // Found a match - return it.
3568 return osr;
3569 }
3570 } else {
3571 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3572 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3573 // Found the best possible - return it.
3574 return osr;
3575 }
3576 best = osr;
3577 }
3578 }
3579 }
3580 osr = osr->osr_link();
3581 }
3582
3583 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3584 if (best != nullptr && best->comp_level() >= comp_level) {
3585 return best;
3586 }
3587 return nullptr;
3588 }
3589
3590 // -----------------------------------------------------------------------------------------------------
3591 // Printing
3592
3593 #define BULLET " - "
3594
3595 static const char* state_names[] = {
3596 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3597 };
3598
3599 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3600 for (int i = 0; i < len; i++) {
3601 intptr_t e = start[i];
3602 st->print("%d : " INTPTR_FORMAT, i, e);
3603 if (MetaspaceObj::is_valid((Metadata*)e)) {
3604 st->print(" ");
3605 ((Metadata*)e)->print_value_on(st);
3606 }
3607 st->cr();
3608 }
3609 }
3610
3611 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3612 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3613 }
3614
3615 const char* InstanceKlass::init_state_name() const {
3616 return state_names[init_state()];
3617 }
3618
3619 void InstanceKlass::print_on(outputStream* st) const {
3620 assert(is_klass(), "must be klass");
3621 Klass::print_on(st);
3622
3623 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3624 st->print(BULLET"klass size: %d", size()); st->cr();
3625 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3626 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3627 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3628 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3629 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3630 st->print(BULLET"sub: ");
3631 Klass* sub = subklass();
3632 int n;
3633 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3634 if (n < MaxSubklassPrintSize) {
3635 sub->print_value_on(st);
3636 st->print(" ");
3637 }
3638 }
3639 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3640 st->cr();
3641
3642 if (is_interface()) {
3643 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3644 if (nof_implementors() == 1) {
3645 st->print_cr(BULLET"implementor: ");
3646 st->print(" ");
3647 implementor()->print_value_on(st);
3648 st->cr();
3649 }
3650 }
3651
3652 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3653 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3654 if (Verbose || WizardMode) {
3655 Array<Method*>* method_array = methods();
3656 for (int i = 0; i < method_array->length(); i++) {
3657 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3658 }
3659 }
3660 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3661 if (default_methods() != nullptr) {
3662 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3663 if (Verbose) {
3664 Array<Method*>* method_array = default_methods();
3665 for (int i = 0; i < method_array->length(); i++) {
3666 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3667 }
3668 }
3669 }
3670 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3671 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3672 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3673
3674 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3675
3676 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3677 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3678
3679 if (secondary_supers() != nullptr) {
3680 if (Verbose) {
3681 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3682 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3683 for (int i = 0; i < _secondary_supers->length(); i++) {
3684 ResourceMark rm; // for external_name()
3685 Klass* secondary_super = _secondary_supers->at(i);
3686 st->print(BULLET"%2d:", i);
3687 if (is_hashed) {
3688 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3689 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3690 st->print(" dist:%02d:", distance);
3691 }
3692 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3693 }
3694 }
3695 }
3696 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3697
3698 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3699 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3700 if (source_debug_extension() != nullptr) {
3701 st->print(BULLET"source debug extension: ");
3702 st->print("%s", source_debug_extension());
3703 st->cr();
3704 }
3705 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3706 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3707 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3708 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3709 {
3710 bool have_pv = false;
3711 // previous versions are linked together through the InstanceKlass
3712 for (InstanceKlass* pv_node = previous_versions();
3713 pv_node != nullptr;
3714 pv_node = pv_node->previous_versions()) {
3715 if (!have_pv)
3716 st->print(BULLET"previous version: ");
3717 have_pv = true;
3718 pv_node->constants()->print_value_on(st);
3719 }
3720 if (have_pv) st->cr();
3721 }
3722
3723 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3724 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3725 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3726 print_on_maybe_null(st, BULLET"record components: ", record_components());
3727 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3728 if (java_mirror() != nullptr) {
3729 st->print(BULLET"java mirror: ");
3730 java_mirror()->print_value_on(st);
3731 st->cr();
3732 } else {
3733 st->print_cr(BULLET"java mirror: null");
3734 }
3735 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3736 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3737 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3738 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3739 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3740
3741 FieldPrinter print_static_field(st);
3742 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3743 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3744 FieldPrinter print_nonstatic_field(st);
3745 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3746 ik->print_nonstatic_fields(&print_nonstatic_field);
3747
3748 st->print(BULLET"non-static oop maps: ");
3749 OopMapBlock* map = start_of_nonstatic_oop_maps();
3750 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3751 while (map < end_map) {
3752 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3753 map++;
3754 }
3755 st->cr();
3756 }
3757
3758 void InstanceKlass::print_value_on(outputStream* st) const {
3759 assert(is_klass(), "must be klass");
3760 if (Verbose || WizardMode) access_flags().print_on(st);
3761 name()->print_value_on(st);
3762 }
3763
3764 void FieldPrinter::do_field(fieldDescriptor* fd) {
3765 _st->print(BULLET);
3766 if (_obj == nullptr) {
3767 fd->print_on(_st);
3768 _st->cr();
3769 } else {
3770 fd->print_on_for(_st, _obj);
3771 _st->cr();
3772 }
3773 }
3774
3775
3776 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3777 Klass::oop_print_on(obj, st);
3778
3779 if (this == vmClasses::String_klass()) {
3780 typeArrayOop value = java_lang_String::value(obj);
3781 juint length = java_lang_String::length(obj);
3782 if (value != nullptr &&
3783 value->is_typeArray() &&
3784 length <= (juint) value->length()) {
3785 st->print(BULLET"string: ");
3786 java_lang_String::print(obj, st);
3787 st->cr();
3788 }
3789 }
3790
3791 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3792 FieldPrinter print_field(st, obj);
3793 print_nonstatic_fields(&print_field);
3794
3795 if (this == vmClasses::Class_klass()) {
3796 st->print(BULLET"signature: ");
3797 java_lang_Class::print_signature(obj, st);
3798 st->cr();
3799 Klass* real_klass = java_lang_Class::as_Klass(obj);
3800 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3801 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3802 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3803 }
3804 } else if (this == vmClasses::MethodType_klass()) {
3805 st->print(BULLET"signature: ");
3806 java_lang_invoke_MethodType::print_signature(obj, st);
3807 st->cr();
3808 }
3809 }
3810
3811 #ifndef PRODUCT
3812
3813 bool InstanceKlass::verify_itable_index(int i) {
3814 int method_count = klassItable::method_count_for_interface(this);
3815 assert(i >= 0 && i < method_count, "index out of bounds");
3816 return true;
3817 }
3818
3819 #endif //PRODUCT
3820
3821 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3822 st->print("a ");
3823 name()->print_value_on(st);
3824 obj->print_address_on(st);
3825 if (this == vmClasses::String_klass()
3826 && java_lang_String::value(obj) != nullptr) {
3827 ResourceMark rm;
3828 int len = java_lang_String::length(obj);
3829 int plen = (len < 24 ? len : 12);
3830 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3831 st->print(" = \"%s\"", str);
3832 if (len > plen)
3833 st->print("...[%d]", len);
3834 } else if (this == vmClasses::Class_klass()) {
3835 Klass* k = java_lang_Class::as_Klass(obj);
3836 st->print(" = ");
3837 if (k != nullptr) {
3838 k->print_value_on(st);
3839 } else {
3840 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3841 st->print("%s", tname ? tname : "type?");
3842 }
3843 } else if (this == vmClasses::MethodType_klass()) {
3844 st->print(" = ");
3845 java_lang_invoke_MethodType::print_signature(obj, st);
3846 } else if (java_lang_boxing_object::is_instance(obj)) {
3847 st->print(" = ");
3848 java_lang_boxing_object::print(obj, st);
3849 } else if (this == vmClasses::LambdaForm_klass()) {
3850 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3851 if (vmentry != nullptr) {
3852 st->print(" => ");
3853 vmentry->print_value_on(st);
3854 }
3855 } else if (this == vmClasses::MemberName_klass()) {
3856 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3857 if (vmtarget != nullptr) {
3858 st->print(" = ");
3859 vmtarget->print_value_on(st);
3860 } else {
3861 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3862 oop name = java_lang_invoke_MemberName::name(obj);
3863 if (clazz != nullptr) {
3864 clazz->print_value_on(st);
3865 } else {
3866 st->print("null");
3867 }
3868 st->print(".");
3869 if (name != nullptr) {
3870 name->print_value_on(st);
3871 } else {
3872 st->print("null");
3873 }
3874 }
3875 }
3876 }
3877
3878 const char* InstanceKlass::internal_name() const {
3879 return external_name();
3880 }
3881
3882 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3883 const ModuleEntry* module_entry,
3884 const ClassFileStream* cfs) const {
3885
3886 if (ClassListWriter::is_enabled()) {
3887 ClassListWriter::write(this, cfs);
3888 }
3889
3890 print_class_load_helper(loader_data, module_entry, cfs);
3891 print_class_load_cause_logging();
3892 }
3893
3894 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3895 const ModuleEntry* module_entry,
3896 const ClassFileStream* cfs) const {
3897
3898 if (!log_is_enabled(Info, class, load)) {
3899 return;
3900 }
3901
3902 ResourceMark rm;
3903 LogMessage(class, load) msg;
3904 stringStream info_stream;
3905
3906 // Name and class hierarchy info
3907 info_stream.print("%s", external_name());
3908
3909 // Source
3910 if (cfs != nullptr) {
3911 if (cfs->source() != nullptr) {
3912 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3913 if (module_name != nullptr) {
3914 // When the boot loader created the stream, it didn't know the module name
3915 // yet. Let's format it now.
3916 if (cfs->from_boot_loader_modules_image()) {
3917 info_stream.print(" source: jrt:/%s", module_name);
3918 } else {
3919 info_stream.print(" source: %s", cfs->source());
3920 }
3921 } else {
3922 info_stream.print(" source: %s", cfs->source());
3923 }
3924 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3925 Thread* current = Thread::current();
3926 Klass* caller = current->is_Java_thread() ?
3927 JavaThread::cast(current)->security_get_caller_class(1):
3928 nullptr;
3929 // caller can be null, for example, during a JVMTI VM_Init hook
3930 if (caller != nullptr) {
3931 info_stream.print(" source: instance of %s", caller->external_name());
3932 } else {
3933 // source is unknown
3934 }
3935 } else {
3936 oop class_loader = loader_data->class_loader();
3937 info_stream.print(" source: %s", class_loader->klass()->external_name());
3938 }
3939 } else {
3940 assert(this->is_shared(), "must be");
3941 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3942 info_stream.print(" source: shared objects file (top)");
3943 } else {
3944 info_stream.print(" source: shared objects file");
3945 }
3946 }
3947
3948 msg.info("%s", info_stream.as_string());
3949
3950 if (log_is_enabled(Debug, class, load)) {
3951 stringStream debug_stream;
3952
3953 // Class hierarchy info
3954 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
3955 p2i(this), p2i(superklass()));
3956
3957 // Interfaces
3958 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
3959 debug_stream.print(" interfaces:");
3960 int length = local_interfaces()->length();
3961 for (int i = 0; i < length; i++) {
3962 debug_stream.print(" " PTR_FORMAT,
3963 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3964 }
3965 }
3966
3967 // Class loader
3968 debug_stream.print(" loader: [");
3969 loader_data->print_value_on(&debug_stream);
3970 debug_stream.print("]");
3971
3972 // Classfile checksum
3973 if (cfs) {
3974 debug_stream.print(" bytes: %d checksum: %08x",
3975 cfs->length(),
3976 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3977 cfs->length()));
3978 }
3979
3980 msg.debug("%s", debug_stream.as_string());
3981 }
3982 }
3983
3984 void InstanceKlass::print_class_load_cause_logging() const {
3985 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
3986 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
3987 JavaThread* current = JavaThread::current();
3988 ResourceMark rm(current);
3989 const char* name = external_name();
3990
3991 if (LogClassLoadingCauseFor == nullptr ||
3992 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
3993 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
3994 return;
3995 }
3996
3997 // Log Java stack first
3998 {
3999 LogMessage(class, load, cause) msg;
4000 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4001
4002 info_stream.print_cr("Java stack when loading %s:", name);
4003 current->print_stack_on(&info_stream);
4004 }
4005
4006 // Log native stack second
4007 if (log_cause_native) {
4008 // Log to string first so that lines can be indented
4009 stringStream stack_stream;
4010 char buf[O_BUFLEN];
4011 address lastpc = nullptr;
4012 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4013 // We have printed the native stack in platform-specific code,
4014 // so nothing else to do in this case.
4015 } else {
4016 frame f = os::current_frame();
4017 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4018 -1 /* max stack_stream */, buf, O_BUFLEN);
4019 }
4020
4021 LogMessage(class, load, cause, native) msg;
4022 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4023 info_stream.print_cr("Native stack when loading %s:", name);
4024
4025 // Print each native stack line to the log
4026 int size = (int) stack_stream.size();
4027 char* stack = stack_stream.as_string();
4028 char* stack_end = stack + size;
4029 char* line_start = stack;
4030 for (char* p = stack; p < stack_end; p++) {
4031 if (*p == '\n') {
4032 *p = '\0';
4033 info_stream.print_cr("\t%s", line_start);
4034 line_start = p + 1;
4035 }
4036 }
4037 if (line_start < stack_end) {
4038 info_stream.print_cr("\t%s", line_start);
4039 }
4040 }
4041 }
4042 }
4043
4044 // Verification
4045
4046 class VerifyFieldClosure: public BasicOopIterateClosure {
4047 protected:
4048 template <class T> void do_oop_work(T* p) {
4049 oop obj = RawAccess<>::oop_load(p);
4050 if (!oopDesc::is_oop_or_null(obj)) {
4051 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4052 Universe::print_on(tty);
4053 guarantee(false, "boom");
4054 }
4055 }
4056 public:
4057 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4058 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4059 };
4060
4061 void InstanceKlass::verify_on(outputStream* st) {
4062 #ifndef PRODUCT
4063 // Avoid redundant verifies, this really should be in product.
4064 if (_verify_count == Universe::verify_count()) return;
4065 _verify_count = Universe::verify_count();
4066 #endif
4067
4068 // Verify Klass
4069 Klass::verify_on(st);
4070
4071 // Verify that klass is present in ClassLoaderData
4072 guarantee(class_loader_data()->contains_klass(this),
4073 "this class isn't found in class loader data");
4074
4075 // Verify vtables
4076 if (is_linked()) {
4077 // $$$ This used to be done only for m/s collections. Doing it
4078 // always seemed a valid generalization. (DLD -- 6/00)
4079 vtable().verify(st);
4080 }
4081
4082 // Verify first subklass
4083 if (subklass() != nullptr) {
4084 guarantee(subklass()->is_klass(), "should be klass");
4085 }
4086
4087 // Verify siblings
4088 Klass* super = this->super();
4089 Klass* sib = next_sibling();
4090 if (sib != nullptr) {
4091 if (sib == this) {
4092 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4093 }
4094
4095 guarantee(sib->is_klass(), "should be klass");
4096 guarantee(sib->super() == super, "siblings should have same superklass");
4097 }
4098
4099 // Verify local interfaces
4100 if (local_interfaces()) {
4101 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4102 for (int j = 0; j < local_interfaces->length(); j++) {
4103 InstanceKlass* e = local_interfaces->at(j);
4104 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4105 }
4106 }
4107
4108 // Verify transitive interfaces
4109 if (transitive_interfaces() != nullptr) {
4110 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4111 for (int j = 0; j < transitive_interfaces->length(); j++) {
4112 InstanceKlass* e = transitive_interfaces->at(j);
4113 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4114 }
4115 }
4116
4117 // Verify methods
4118 if (methods() != nullptr) {
4119 Array<Method*>* methods = this->methods();
4120 for (int j = 0; j < methods->length(); j++) {
4121 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4122 }
4123 for (int j = 0; j < methods->length() - 1; j++) {
4124 Method* m1 = methods->at(j);
4125 Method* m2 = methods->at(j + 1);
4126 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4127 }
4128 }
4129
4130 // Verify method ordering
4131 if (method_ordering() != nullptr) {
4132 Array<int>* method_ordering = this->method_ordering();
4133 int length = method_ordering->length();
4134 if (JvmtiExport::can_maintain_original_method_order() ||
4135 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4136 guarantee(length == methods()->length(), "invalid method ordering length");
4137 jlong sum = 0;
4138 for (int j = 0; j < length; j++) {
4139 int original_index = method_ordering->at(j);
4140 guarantee(original_index >= 0, "invalid method ordering index");
4141 guarantee(original_index < length, "invalid method ordering index");
4142 sum += original_index;
4143 }
4144 // Verify sum of indices 0,1,...,length-1
4145 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4146 } else {
4147 guarantee(length == 0, "invalid method ordering length");
4148 }
4149 }
4150
4151 // Verify default methods
4152 if (default_methods() != nullptr) {
4153 Array<Method*>* methods = this->default_methods();
4154 for (int j = 0; j < methods->length(); j++) {
4155 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4156 }
4157 for (int j = 0; j < methods->length() - 1; j++) {
4158 Method* m1 = methods->at(j);
4159 Method* m2 = methods->at(j + 1);
4160 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4161 }
4162 }
4163
4164 // Verify JNI static field identifiers
4165 if (jni_ids() != nullptr) {
4166 jni_ids()->verify(this);
4167 }
4168
4169 // Verify other fields
4170 if (constants() != nullptr) {
4171 guarantee(constants()->is_constantPool(), "should be constant pool");
4172 }
4173 }
4174
4175 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4176 Klass::oop_verify_on(obj, st);
4177 VerifyFieldClosure blk;
4178 obj->oop_iterate(&blk);
4179 }
4180
4181
4182 // JNIid class for jfieldIDs only
4183 // Note to reviewers:
4184 // These JNI functions are just moved over to column 1 and not changed
4185 // in the compressed oops workspace.
4186 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4187 _holder = holder;
4188 _offset = offset;
4189 _next = next;
4190 debug_only(_is_static_field_id = false;)
4191 }
4192
4193
4194 JNIid* JNIid::find(int offset) {
4195 JNIid* current = this;
4196 while (current != nullptr) {
4197 if (current->offset() == offset) return current;
4198 current = current->next();
4199 }
4200 return nullptr;
4201 }
4202
4203 void JNIid::deallocate(JNIid* current) {
4204 while (current != nullptr) {
4205 JNIid* next = current->next();
4206 delete current;
4207 current = next;
4208 }
4209 }
4210
4211
4212 void JNIid::verify(Klass* holder) {
4213 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4214 int end_field_offset;
4215 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4216
4217 JNIid* current = this;
4218 while (current != nullptr) {
4219 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4220 #ifdef ASSERT
4221 int o = current->offset();
4222 if (current->is_static_field_id()) {
4223 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4224 }
4225 #endif
4226 current = current->next();
4227 }
4228 }
4229
4230 void InstanceKlass::set_init_state(ClassState state) {
4231 #ifdef ASSERT
4232 bool good_state = is_shared() ? (_init_state <= state)
4233 : (_init_state < state);
4234 assert(good_state || state == allocated, "illegal state transition");
4235 #endif
4236 assert(_init_thread == nullptr, "should be cleared before state change");
4237 Atomic::release_store(&_init_state, state);
4238 }
4239
4240 #if INCLUDE_JVMTI
4241
4242 // RedefineClasses() support for previous versions
4243
4244 // Globally, there is at least one previous version of a class to walk
4245 // during class unloading, which is saved because old methods in the class
4246 // are still running. Otherwise the previous version list is cleaned up.
4247 bool InstanceKlass::_should_clean_previous_versions = false;
4248
4249 // Returns true if there are previous versions of a class for class
4250 // unloading only. Also resets the flag to false. purge_previous_version
4251 // will set the flag to true if there are any left, i.e., if there's any
4252 // work to do for next time. This is to avoid the expensive code cache
4253 // walk in CLDG::clean_deallocate_lists().
4254 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4255 bool ret = _should_clean_previous_versions;
4256 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4257 ret ? "true" : "false");
4258 _should_clean_previous_versions = false;
4259 return ret;
4260 }
4261
4262 // This nulls out jmethodIDs for all methods in 'klass'
4263 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4264 // during class unloading.
4265 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4266 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4267 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4268 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4269 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4270 Array<Method*>* method_refs = klass->methods();
4271 for (int k = 0; k < method_refs->length(); k++) {
4272 Method* method = method_refs->at(k);
4273 if (method != nullptr && method->is_obsolete()) {
4274 method->clear_jmethod_id();
4275 }
4276 }
4277 }
4278
4279 // Purge previous versions before adding new previous versions of the class and
4280 // during class unloading.
4281 void InstanceKlass::purge_previous_version_list() {
4282 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4283 assert(has_been_redefined(), "Should only be called for main class");
4284
4285 // Quick exit.
4286 if (previous_versions() == nullptr) {
4287 return;
4288 }
4289
4290 // This klass has previous versions so see what we can cleanup
4291 // while it is safe to do so.
4292
4293 int deleted_count = 0; // leave debugging breadcrumbs
4294 int live_count = 0;
4295 ClassLoaderData* loader_data = class_loader_data();
4296 assert(loader_data != nullptr, "should never be null");
4297
4298 ResourceMark rm;
4299 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4300
4301 // previous versions are linked together through the InstanceKlass
4302 InstanceKlass* pv_node = previous_versions();
4303 InstanceKlass* last = this;
4304 int version = 0;
4305
4306 // check the previous versions list
4307 for (; pv_node != nullptr; ) {
4308
4309 ConstantPool* pvcp = pv_node->constants();
4310 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4311
4312 if (!pvcp->on_stack()) {
4313 // If the constant pool isn't on stack, none of the methods
4314 // are executing. Unlink this previous_version.
4315 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4316 // so will be deallocated during the next phase of class unloading.
4317 log_trace(redefine, class, iklass, purge)
4318 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4319 // Unlink from previous version list.
4320 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4321 InstanceKlass* next = pv_node->previous_versions();
4322 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4323 pv_node->link_previous_versions(nullptr); // point next to null
4324 last->link_previous_versions(next);
4325 // Delete this node directly. Nothing is referring to it and we don't
4326 // want it to increase the counter for metadata to delete in CLDG.
4327 MetadataFactory::free_metadata(loader_data, pv_node);
4328 pv_node = next;
4329 deleted_count++;
4330 version++;
4331 continue;
4332 } else {
4333 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4334 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4335 live_count++;
4336 if (pvcp->is_shared()) {
4337 // Shared previous versions can never be removed so no cleaning is needed.
4338 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4339 } else {
4340 // Previous version alive, set that clean is needed for next time.
4341 _should_clean_previous_versions = true;
4342 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4343 }
4344 }
4345
4346 // next previous version
4347 last = pv_node;
4348 pv_node = pv_node->previous_versions();
4349 version++;
4350 }
4351 log_trace(redefine, class, iklass, purge)
4352 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4353 }
4354
4355 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4356 int emcp_method_count) {
4357 int obsolete_method_count = old_methods->length() - emcp_method_count;
4358
4359 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4360 _previous_versions != nullptr) {
4361 // We have a mix of obsolete and EMCP methods so we have to
4362 // clear out any matching EMCP method entries the hard way.
4363 int local_count = 0;
4364 for (int i = 0; i < old_methods->length(); i++) {
4365 Method* old_method = old_methods->at(i);
4366 if (old_method->is_obsolete()) {
4367 // only obsolete methods are interesting
4368 Symbol* m_name = old_method->name();
4369 Symbol* m_signature = old_method->signature();
4370
4371 // previous versions are linked together through the InstanceKlass
4372 int j = 0;
4373 for (InstanceKlass* prev_version = _previous_versions;
4374 prev_version != nullptr;
4375 prev_version = prev_version->previous_versions(), j++) {
4376
4377 Array<Method*>* method_refs = prev_version->methods();
4378 for (int k = 0; k < method_refs->length(); k++) {
4379 Method* method = method_refs->at(k);
4380
4381 if (!method->is_obsolete() &&
4382 method->name() == m_name &&
4383 method->signature() == m_signature) {
4384 // The current RedefineClasses() call has made all EMCP
4385 // versions of this method obsolete so mark it as obsolete
4386 log_trace(redefine, class, iklass, add)
4387 ("%s(%s): flush obsolete method @%d in version @%d",
4388 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4389
4390 method->set_is_obsolete();
4391 break;
4392 }
4393 }
4394
4395 // The previous loop may not find a matching EMCP method, but
4396 // that doesn't mean that we can optimize and not go any
4397 // further back in the PreviousVersion generations. The EMCP
4398 // method for this generation could have already been made obsolete,
4399 // but there still may be an older EMCP method that has not
4400 // been made obsolete.
4401 }
4402
4403 if (++local_count >= obsolete_method_count) {
4404 // no more obsolete methods so bail out now
4405 break;
4406 }
4407 }
4408 }
4409 }
4410 }
4411
4412 // Save the scratch_class as the previous version if any of the methods are running.
4413 // The previous_versions are used to set breakpoints in EMCP methods and they are
4414 // also used to clean MethodData links to redefined methods that are no longer running.
4415 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4416 int emcp_method_count) {
4417 assert(Thread::current()->is_VM_thread(),
4418 "only VMThread can add previous versions");
4419
4420 ResourceMark rm;
4421 log_trace(redefine, class, iklass, add)
4422 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4423
4424 // Clean out old previous versions for this class
4425 purge_previous_version_list();
4426
4427 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4428 // a previous redefinition may be made obsolete by this redefinition.
4429 Array<Method*>* old_methods = scratch_class->methods();
4430 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4431
4432 // If the constant pool for this previous version of the class
4433 // is not marked as being on the stack, then none of the methods
4434 // in this previous version of the class are on the stack so
4435 // we don't need to add this as a previous version.
4436 ConstantPool* cp_ref = scratch_class->constants();
4437 if (!cp_ref->on_stack()) {
4438 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4439 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4440 return;
4441 }
4442
4443 // Add previous version if any methods are still running or if this is
4444 // a shared class which should never be removed.
4445 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4446 scratch_class->link_previous_versions(previous_versions());
4447 link_previous_versions(scratch_class);
4448 if (cp_ref->is_shared()) {
4449 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4450 } else {
4451 // We only set clean_previous_versions flag for processing during class
4452 // unloading for non-shared classes.
4453 _should_clean_previous_versions = true;
4454 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4455 }
4456 } // end add_previous_version()
4457
4458 #endif // INCLUDE_JVMTI
4459
4460 Method* InstanceKlass::method_with_idnum(int idnum) {
4461 Method* m = nullptr;
4462 if (idnum < methods()->length()) {
4463 m = methods()->at(idnum);
4464 }
4465 if (m == nullptr || m->method_idnum() != idnum) {
4466 for (int index = 0; index < methods()->length(); ++index) {
4467 m = methods()->at(index);
4468 if (m->method_idnum() == idnum) {
4469 return m;
4470 }
4471 }
4472 // None found, return null for the caller to handle.
4473 return nullptr;
4474 }
4475 return m;
4476 }
4477
4478
4479 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4480 if (idnum >= methods()->length()) {
4481 return nullptr;
4482 }
4483 Method* m = methods()->at(idnum);
4484 if (m != nullptr && m->orig_method_idnum() == idnum) {
4485 return m;
4486 }
4487 // Obsolete method idnum does not match the original idnum
4488 for (int index = 0; index < methods()->length(); ++index) {
4489 m = methods()->at(index);
4490 if (m->orig_method_idnum() == idnum) {
4491 return m;
4492 }
4493 }
4494 // None found, return null for the caller to handle.
4495 return nullptr;
4496 }
4497
4498
4499 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4500 InstanceKlass* holder = get_klass_version(version);
4501 if (holder == nullptr) {
4502 return nullptr; // The version of klass is gone, no method is found
4503 }
4504 Method* method = holder->method_with_orig_idnum(idnum);
4505 return method;
4506 }
4507
4508 #if INCLUDE_JVMTI
4509 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4510 return _cached_class_file;
4511 }
4512
4513 jint InstanceKlass::get_cached_class_file_len() {
4514 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4515 }
4516
4517 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4518 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4519 }
4520 #endif
4521
4522 // Make a step iterating over the class hierarchy under the root class.
4523 // Skips subclasses if requested.
4524 void ClassHierarchyIterator::next() {
4525 assert(_current != nullptr, "required");
4526 if (_visit_subclasses && _current->subklass() != nullptr) {
4527 _current = _current->subklass();
4528 return; // visit next subclass
4529 }
4530 _visit_subclasses = true; // reset
4531 while (_current->next_sibling() == nullptr && _current != _root) {
4532 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4533 }
4534 if (_current == _root) {
4535 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4536 _current = nullptr;
4537 return;
4538 }
4539 _current = _current->next_sibling();
4540 return; // visit next sibling subclass
4541 }