1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotClassInitializer.hpp"
26 #include "cds/aotMetaspace.hpp"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/cdsEnumKlass.hpp"
30 #include "cds/classListWriter.hpp"
31 #include "cds/heapShared.hpp"
32 #include "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeStream.hpp"
49 #include "interpreter/oopMapCache.hpp"
50 #include "interpreter/rewriter.hpp"
51 #include "jvm.h"
52 #include "jvmtifiles/jvmti.h"
53 #include "klass.inline.hpp"
54 #include "logging/log.hpp"
55 #include "logging/logMessage.hpp"
56 #include "logging/logStream.hpp"
57 #include "memory/allocation.inline.hpp"
58 #include "memory/iterator.inline.hpp"
59 #include "memory/metadataFactory.hpp"
60 #include "memory/metaspaceClosure.hpp"
61 #include "memory/oopFactory.hpp"
62 #include "memory/resourceArea.hpp"
63 #include "memory/universe.hpp"
64 #include "oops/constantPool.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/instanceClassLoaderKlass.hpp"
67 #include "oops/instanceKlass.inline.hpp"
68 #include "oops/instanceMirrorKlass.hpp"
69 #include "oops/instanceOop.hpp"
70 #include "oops/instanceStackChunkKlass.hpp"
71 #include "oops/klass.inline.hpp"
72 #include "oops/method.hpp"
73 #include "oops/oop.inline.hpp"
74 #include "oops/recordComponent.hpp"
75 #include "oops/symbol.hpp"
76 #include "prims/jvmtiExport.hpp"
77 #include "prims/jvmtiRedefineClasses.hpp"
78 #include "prims/jvmtiThreadState.hpp"
79 #include "prims/methodComparator.hpp"
80 #include "runtime/arguments.hpp"
81 #include "runtime/atomicAccess.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/fieldDescriptor.inline.hpp"
84 #include "runtime/handles.inline.hpp"
85 #include "runtime/javaCalls.hpp"
86 #include "runtime/javaThread.inline.hpp"
87 #include "runtime/mutexLocker.hpp"
88 #include "runtime/orderAccess.hpp"
89 #include "runtime/os.inline.hpp"
90 #include "runtime/reflection.hpp"
91 #include "runtime/synchronizer.hpp"
92 #include "runtime/threads.hpp"
93 #include "services/classLoadingService.hpp"
94 #include "services/finalizerService.hpp"
95 #include "services/threadService.hpp"
96 #include "utilities/dtrace.hpp"
97 #include "utilities/events.hpp"
98 #include "utilities/macros.hpp"
99 #include "utilities/nativeStackPrinter.hpp"
100 #include "utilities/stringUtils.hpp"
101 #ifdef COMPILER1
102 #include "c1/c1_Compiler.hpp"
103 #endif
104 #if INCLUDE_JFR
105 #include "jfr/jfrEvents.hpp"
106 #endif
107
108 #ifdef DTRACE_ENABLED
109
110
111 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
112 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
113 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
114 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
115 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
116 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
117 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
118 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
119 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
120 { \
121 char* data = nullptr; \
122 int len = 0; \
123 Symbol* clss_name = name(); \
124 if (clss_name != nullptr) { \
125 data = (char*)clss_name->bytes(); \
126 len = clss_name->utf8_length(); \
127 } \
128 HOTSPOT_CLASS_INITIALIZATION_##type( \
129 data, len, (void*)class_loader(), thread_type); \
130 }
131
132 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
133 { \
134 char* data = nullptr; \
135 int len = 0; \
136 Symbol* clss_name = name(); \
137 if (clss_name != nullptr) { \
138 data = (char*)clss_name->bytes(); \
139 len = clss_name->utf8_length(); \
140 } \
141 HOTSPOT_CLASS_INITIALIZATION_##type( \
142 data, len, (void*)class_loader(), thread_type, wait); \
143 }
144
145 #else // ndef DTRACE_ENABLED
146
147 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
148 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
149
150 #endif // ndef DTRACE_ENABLED
151
152 bool InstanceKlass::_finalization_enabled = true;
153
154 static inline bool is_class_loader(const Symbol* class_name,
155 const ClassFileParser& parser) {
156 assert(class_name != nullptr, "invariant");
157
158 if (class_name == vmSymbols::java_lang_ClassLoader()) {
159 return true;
160 }
161
162 if (vmClasses::ClassLoader_klass_is_loaded()) {
163 const Klass* const super_klass = parser.super_klass();
164 if (super_klass != nullptr) {
165 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
166 return true;
167 }
168 }
169 }
170 return false;
171 }
172
173 static inline bool is_stack_chunk_class(const Symbol* class_name,
174 const ClassLoaderData* loader_data) {
175 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
176 loader_data->is_the_null_class_loader_data());
177 }
178
179 // private: called to verify that k is a static member of this nest.
180 // We know that k is an instance class in the same package and hence the
181 // same classloader.
182 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
183 assert(!is_hidden(), "unexpected hidden class");
184 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
185 if (log_is_enabled(Trace, class, nestmates)) {
186 ResourceMark rm(current);
187 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
188 k->external_name(), this->external_name());
189 }
190 return false;
191 }
192
193 if (log_is_enabled(Trace, class, nestmates)) {
194 ResourceMark rm(current);
195 log_trace(class, nestmates)("Checking nest membership of %s in %s",
196 k->external_name(), this->external_name());
197 }
198
199 // Check for the named class in _nest_members.
200 // We don't resolve, or load, any classes.
201 for (int i = 0; i < _nest_members->length(); i++) {
202 int cp_index = _nest_members->at(i);
203 Symbol* name = _constants->klass_name_at(cp_index);
204 if (name == k->name()) {
205 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
206 return true;
207 }
208 }
209 log_trace(class, nestmates)("- class is NOT a nest member!");
210 return false;
211 }
212
213 // Called to verify that k is a permitted subclass of this class.
214 // The incoming stringStream is used to format the messages for error logging and for the caller
215 // to use for exception throwing.
216 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
217 Thread* current = Thread::current();
218 assert(k != nullptr, "sanity check");
219 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
220 "unexpected empty _permitted_subclasses array");
221
222 if (log_is_enabled(Trace, class, sealed)) {
223 ResourceMark rm(current);
224 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
225 k->external_name(), this->external_name());
226 }
227
228 // Check that the class and its super are in the same module.
229 if (k->module() != this->module()) {
230 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
231 "and sealed class %s is in module '%s' with loader %s",
232 k->external_name(),
233 k->module()->name_as_C_string(),
234 k->module()->loader_data()->loader_name_and_id(),
235 this->external_name(),
236 this->module()->name_as_C_string(),
237 this->module()->loader_data()->loader_name_and_id());
238 log_trace(class, sealed)(" - %s", ss.as_string());
239 return false;
240 }
241
242 if (!k->is_public() && !is_same_class_package(k)) {
243 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
244 "and sealed class %s is in package '%s' with classloader %s",
245 k->external_name(),
246 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
247 k->module()->loader_data()->loader_name_and_id(),
248 this->external_name(),
249 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
250 this->module()->loader_data()->loader_name_and_id());
251 log_trace(class, sealed)(" - %s", ss.as_string());
252 return false;
253 }
254
255 for (int i = 0; i < _permitted_subclasses->length(); i++) {
256 int cp_index = _permitted_subclasses->at(i);
257 Symbol* name = _constants->klass_name_at(cp_index);
258 if (name == k->name()) {
259 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
260 return true;
261 }
262 }
263
264 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
265 k->external_name(), this->external_name());
266 log_trace(class, sealed)(" - %s", ss.as_string());
267 return false;
268 }
269
270 // Return nest-host class, resolving, validating and saving it if needed.
271 // In cases where this is called from a thread that cannot do classloading
272 // (such as a native JIT thread) then we simply return null, which in turn
273 // causes the access check to return false. Such code will retry the access
274 // from a more suitable environment later. Otherwise the _nest_host is always
275 // set once this method returns.
276 // Any errors from nest-host resolution must be preserved so they can be queried
277 // from higher-level access checking code, and reported as part of access checking
278 // exceptions.
279 // VirtualMachineErrors are propagated with a null return.
280 // Under any conditions where the _nest_host can be set to non-null the resulting
281 // value of it and, if applicable, the nest host resolution/validation error,
282 // are idempotent.
283 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
284 InstanceKlass* nest_host_k = _nest_host;
285 if (nest_host_k != nullptr) {
286 return nest_host_k;
287 }
288
289 ResourceMark rm(THREAD);
290
291 // need to resolve and save our nest-host class.
292 if (_nest_host_index != 0) { // we have a real nest_host
293 // Before trying to resolve check if we're in a suitable context
294 bool can_resolve = THREAD->can_call_java();
295 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
296 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
297 this->external_name());
298 return nullptr; // sentinel to say "try again from a different context"
299 }
300
301 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
302 this->external_name(),
303 _constants->klass_name_at(_nest_host_index)->as_C_string());
304
305 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
306 if (HAS_PENDING_EXCEPTION) {
307 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
308 return nullptr; // propagate VMEs
309 }
310 stringStream ss;
311 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
312 ss.print("Nest host resolution of %s with host %s failed: ",
313 this->external_name(), target_host_class);
314 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
315 const char* msg = ss.as_string(true /* on C-heap */);
316 constantPoolHandle cph(THREAD, constants());
317 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
318 CLEAR_PENDING_EXCEPTION;
319
320 log_trace(class, nestmates)("%s", msg);
321 } else {
322 // A valid nest-host is an instance class in the current package that lists this
323 // class as a nest member. If any of these conditions are not met the class is
324 // its own nest-host.
325 const char* error = nullptr;
326
327 // JVMS 5.4.4 indicates package check comes first
328 if (is_same_class_package(k)) {
329 // Now check actual membership. We can't be a member if our "host" is
330 // not an instance class.
331 if (k->is_instance_klass()) {
332 nest_host_k = InstanceKlass::cast(k);
333 bool is_member = nest_host_k->has_nest_member(THREAD, this);
334 if (is_member) {
335 _nest_host = nest_host_k; // save resolved nest-host value
336
337 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
338 this->external_name(), k->external_name());
339 return nest_host_k;
340 } else {
341 error = "current type is not listed as a nest member";
342 }
343 } else {
344 error = "host is not an instance class";
345 }
346 } else {
347 error = "types are in different packages";
348 }
349
350 // something went wrong, so record what and log it
351 {
352 stringStream ss;
353 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
354 this->external_name(),
355 this->class_loader_data()->loader_name_and_id(),
356 k->external_name(),
357 k->class_loader_data()->loader_name_and_id(),
358 error);
359 const char* msg = ss.as_string(true /* on C-heap */);
360 constantPoolHandle cph(THREAD, constants());
361 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
362 log_trace(class, nestmates)("%s", msg);
363 }
364 }
365 } else {
366 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
367 this->external_name());
368 }
369
370 // Either not in an explicit nest, or else an error occurred, so
371 // the nest-host is set to `this`. Any thread that sees this assignment
372 // will also see any setting of nest_host_error(), if applicable.
373 return (_nest_host = this);
374 }
375
376 // Dynamic nest member support: set this class's nest host to the given class.
377 // This occurs as part of the class definition, as soon as the instanceKlass
378 // has been created and doesn't require further resolution. The code:
379 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
380 // results in:
381 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
382 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
383 // We also know the "host" is a valid nest-host in the same package so we can
384 // assert some of those facts.
385 void InstanceKlass::set_nest_host(InstanceKlass* host) {
386 assert(is_hidden(), "must be a hidden class");
387 assert(host != nullptr, "null nest host specified");
388 assert(_nest_host == nullptr, "current class has resolved nest-host");
389 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
390 nest_host_error());
391 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
392 (host->_nest_host == host), "proposed host is not a valid nest-host");
393 // Can't assert this as package is not set yet:
394 // assert(is_same_class_package(host), "proposed host is in wrong package");
395
396 if (log_is_enabled(Trace, class, nestmates)) {
397 ResourceMark rm;
398 const char* msg = "";
399 // a hidden class does not expect a statically defined nest-host
400 if (_nest_host_index > 0) {
401 msg = "(the NestHost attribute in the current class is ignored)";
402 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
403 msg = "(the NestMembers attribute in the current class is ignored)";
404 }
405 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
406 this->external_name(),
407 host->external_name(),
408 msg);
409 }
410 // set dynamic nest host
411 _nest_host = host;
412 // Record dependency to keep nest host from being unloaded before this class.
413 ClassLoaderData* this_key = class_loader_data();
414 assert(this_key != nullptr, "sanity");
415 this_key->record_dependency(host);
416 }
417
418 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
419 // or we are k's nest_host - all of which is covered by comparing the two
420 // resolved_nest_hosts.
421 // Any exceptions (i.e. VMEs) are propagated.
422 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
423
424 assert(this != k, "this should be handled by higher-level code");
425
426 // Per JVMS 5.4.4 we first resolve and validate the current class, then
427 // the target class k.
428
429 InstanceKlass* cur_host = nest_host(CHECK_false);
430 if (cur_host == nullptr) {
431 return false;
432 }
433
434 Klass* k_nest_host = k->nest_host(CHECK_false);
435 if (k_nest_host == nullptr) {
436 return false;
437 }
438
439 bool access = (cur_host == k_nest_host);
440
441 ResourceMark rm(THREAD);
442 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
443 this->external_name(),
444 access ? "" : "NOT ",
445 k->external_name());
446 return access;
447 }
448
449 const char* InstanceKlass::nest_host_error() {
450 if (_nest_host_index == 0) {
451 return nullptr;
452 } else {
453 constantPoolHandle cph(Thread::current(), constants());
454 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
455 }
456 }
457
458 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
459 const int size = InstanceKlass::size(parser.vtable_size(),
460 parser.itable_size(),
461 nonstatic_oop_map_size(parser.total_oop_map_count()),
462 parser.is_interface());
463
464 const Symbol* const class_name = parser.class_name();
465 assert(class_name != nullptr, "invariant");
466 ClassLoaderData* loader_data = parser.loader_data();
467 assert(loader_data != nullptr, "invariant");
468
469 InstanceKlass* ik;
470
471 // Allocation
472 if (parser.is_instance_ref_klass()) {
473 // java.lang.ref.Reference
474 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
475 } else if (class_name == vmSymbols::java_lang_Class()) {
476 // mirror - java.lang.Class
477 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
478 } else if (is_stack_chunk_class(class_name, loader_data)) {
479 // stack chunk
480 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
481 } else if (is_class_loader(class_name, parser)) {
482 // class loader - java.lang.ClassLoader
483 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
484 } else {
485 // normal
486 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
487 }
488
489 if (ik != nullptr && UseCompressedClassPointers) {
490 assert(CompressedKlassPointers::is_encodable(ik),
491 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
492 }
493
494 // Check for pending exception before adding to the loader data and incrementing
495 // class count. Can get OOM here.
496 if (HAS_PENDING_EXCEPTION) {
497 return nullptr;
498 }
499
500 return ik;
501 }
502
503
504 // copy method ordering from resource area to Metaspace
505 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
506 if (m != nullptr) {
507 // allocate a new array and copy contents (memcpy?)
508 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
509 for (int i = 0; i < m->length(); i++) {
510 _method_ordering->at_put(i, m->at(i));
511 }
512 } else {
513 _method_ordering = Universe::the_empty_int_array();
514 }
515 }
516
517 // create a new array of vtable_indices for default methods
518 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
519 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
520 assert(default_vtable_indices() == nullptr, "only create once");
521 set_default_vtable_indices(vtable_indices);
522 return vtable_indices;
523 }
524
525
526 InstanceKlass::InstanceKlass() {
527 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
528 }
529
530 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
531 Klass(kind),
532 _nest_members(nullptr),
533 _nest_host(nullptr),
534 _permitted_subclasses(nullptr),
535 _record_components(nullptr),
536 _static_field_size(parser.static_field_size()),
537 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
538 _itable_len(parser.itable_size()),
539 _nest_host_index(0),
540 _init_state(allocated),
541 _reference_type(reference_type),
542 _init_thread(nullptr)
543 {
544 set_vtable_length(parser.vtable_size());
545 set_access_flags(parser.access_flags());
546 if (parser.is_hidden()) set_is_hidden();
547 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
548 false));
549
550 assert(nullptr == _methods, "underlying memory not zeroed?");
551 assert(is_instance_klass(), "is layout incorrect?");
552 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
553 }
554
555 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
556 Array<Method*>* methods) {
557 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
558 !methods->in_aot_cache()) {
559 for (int i = 0; i < methods->length(); i++) {
560 Method* method = methods->at(i);
561 if (method == nullptr) continue; // maybe null if error processing
562 // Only want to delete methods that are not executing for RedefineClasses.
563 // The previous version will point to them so they're not totally dangling
564 assert (!method->on_stack(), "shouldn't be called with methods on stack");
565 MetadataFactory::free_metadata(loader_data, method);
566 }
567 MetadataFactory::free_array<Method*>(loader_data, methods);
568 }
569 }
570
571 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
572 const InstanceKlass* super_klass,
573 Array<InstanceKlass*>* local_interfaces,
574 Array<InstanceKlass*>* transitive_interfaces) {
575 // Only deallocate transitive interfaces if not empty, same as super class
576 // or same as local interfaces. See code in parseClassFile.
577 Array<InstanceKlass*>* ti = transitive_interfaces;
578 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
579 // check that the interfaces don't come from super class
580 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
581 super_klass->transitive_interfaces();
582 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
583 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
584 }
585 }
586
587 // local interfaces can be empty
588 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
589 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
590 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
591 }
592 }
593
594 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
595 Array<RecordComponent*>* record_components) {
596 if (record_components != nullptr && !record_components->in_aot_cache()) {
597 for (int i = 0; i < record_components->length(); i++) {
598 RecordComponent* record_component = record_components->at(i);
599 MetadataFactory::free_metadata(loader_data, record_component);
600 }
601 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
602 }
603 }
604
605 // This function deallocates the metadata and C heap pointers that the
606 // InstanceKlass points to.
607 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
608 // Orphan the mirror first, CMS thinks it's still live.
609 if (java_mirror() != nullptr) {
610 java_lang_Class::set_klass(java_mirror(), nullptr);
611 }
612
613 // Also remove mirror from handles
614 loader_data->remove_handle(_java_mirror);
615
616 // Need to take this class off the class loader data list.
617 loader_data->remove_class(this);
618
619 // The array_klass for this class is created later, after error handling.
620 // For class redefinition, we keep the original class so this scratch class
621 // doesn't have an array class. Either way, assert that there is nothing
622 // to deallocate.
623 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
624
625 // Release C heap allocated data that this points to, which includes
626 // reference counting symbol names.
627 // Can't release the constant pool or MethodData C heap data here because the constant
628 // pool can be deallocated separately from the InstanceKlass for default methods and
629 // redefine classes. MethodData can also be released separately.
630 release_C_heap_structures(/* release_sub_metadata */ false);
631
632 deallocate_methods(loader_data, methods());
633 set_methods(nullptr);
634
635 deallocate_record_components(loader_data, record_components());
636 set_record_components(nullptr);
637
638 if (method_ordering() != nullptr &&
639 method_ordering() != Universe::the_empty_int_array() &&
640 !method_ordering()->in_aot_cache()) {
641 MetadataFactory::free_array<int>(loader_data, method_ordering());
642 }
643 set_method_ordering(nullptr);
644
645 // default methods can be empty
646 if (default_methods() != nullptr &&
647 default_methods() != Universe::the_empty_method_array() &&
648 !default_methods()->in_aot_cache()) {
649 MetadataFactory::free_array<Method*>(loader_data, default_methods());
650 }
651 // Do NOT deallocate the default methods, they are owned by superinterfaces.
652 set_default_methods(nullptr);
653
654 // default methods vtable indices can be empty
655 if (default_vtable_indices() != nullptr &&
656 !default_vtable_indices()->in_aot_cache()) {
657 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
658 }
659 set_default_vtable_indices(nullptr);
660
661
662 // This array is in Klass, but remove it with the InstanceKlass since
663 // this place would be the only caller and it can share memory with transitive
664 // interfaces.
665 if (secondary_supers() != nullptr &&
666 secondary_supers() != Universe::the_empty_klass_array() &&
667 // see comments in compute_secondary_supers about the following cast
668 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
669 !secondary_supers()->in_aot_cache()) {
670 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
671 }
672 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
673
674 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
675 set_transitive_interfaces(nullptr);
676 set_local_interfaces(nullptr);
677
678 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
679 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
680 }
681 set_fieldinfo_stream(nullptr);
682
683 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
684 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
685 }
686 set_fieldinfo_search_table(nullptr);
687
688 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
689 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
690 }
691 set_fields_status(nullptr);
692
693 // If a method from a redefined class is using this constant pool, don't
694 // delete it, yet. The new class's previous version will point to this.
695 if (constants() != nullptr) {
696 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
697 if (!constants()->in_aot_cache()) {
698 MetadataFactory::free_metadata(loader_data, constants());
699 }
700 // Delete any cached resolution errors for the constant pool
701 SystemDictionary::delete_resolution_error(constants());
702
703 set_constants(nullptr);
704 }
705
706 if (inner_classes() != nullptr &&
707 inner_classes() != Universe::the_empty_short_array() &&
708 !inner_classes()->in_aot_cache()) {
709 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
710 }
711 set_inner_classes(nullptr);
712
713 if (nest_members() != nullptr &&
714 nest_members() != Universe::the_empty_short_array() &&
715 !nest_members()->in_aot_cache()) {
716 MetadataFactory::free_array<jushort>(loader_data, nest_members());
717 }
718 set_nest_members(nullptr);
719
720 if (permitted_subclasses() != nullptr &&
721 permitted_subclasses() != Universe::the_empty_short_array() &&
722 !permitted_subclasses()->in_aot_cache()) {
723 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
724 }
725 set_permitted_subclasses(nullptr);
726
727 // We should deallocate the Annotations instance if it's not in shared spaces.
728 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
729 MetadataFactory::free_metadata(loader_data, annotations());
730 }
731 set_annotations(nullptr);
732
733 SystemDictionaryShared::handle_class_unloading(this);
734
735 #if INCLUDE_CDS_JAVA_HEAP
736 if (CDSConfig::is_dumping_heap()) {
737 HeapShared::remove_scratch_objects(this);
738 }
739 #endif
740 }
741
742 bool InstanceKlass::is_record() const {
743 return _record_components != nullptr &&
744 is_final() &&
745 super() == vmClasses::Record_klass();
746 }
747
748 bool InstanceKlass::is_sealed() const {
749 return _permitted_subclasses != nullptr &&
750 _permitted_subclasses != Universe::the_empty_short_array();
751 }
752
753 // JLS 8.9: An enum class is either implicitly final and derives
754 // from java.lang.Enum, or else is implicitly sealed to its
755 // anonymous subclasses. This query detects both kinds.
756 // It does not validate the finality or
757 // sealing conditions: it merely checks for a super of Enum.
758 // This is sufficient for recognizing well-formed enums.
759 bool InstanceKlass::is_enum_subclass() const {
760 InstanceKlass* s = super();
761 return (s == vmClasses::Enum_klass() ||
762 (s != nullptr && s->super() == vmClasses::Enum_klass()));
763 }
764
765 bool InstanceKlass::should_be_initialized() const {
766 return !is_initialized();
767 }
768
769 klassItable InstanceKlass::itable() const {
770 return klassItable(const_cast<InstanceKlass*>(this));
771 }
772
773 // JVMTI spec thinks there are signers and protection domain in the
774 // instanceKlass. These accessors pretend these fields are there.
775 // The hprof specification also thinks these fields are in InstanceKlass.
776 oop InstanceKlass::protection_domain() const {
777 // return the protection_domain from the mirror
778 return java_lang_Class::protection_domain(java_mirror());
779 }
780
781 objArrayOop InstanceKlass::signers() const {
782 // return the signers from the mirror
783 return java_lang_Class::signers(java_mirror());
784 }
785
786 oop InstanceKlass::init_lock() const {
787 // return the init lock from the mirror
788 oop lock = java_lang_Class::init_lock(java_mirror());
789 // Prevent reordering with any access of initialization state
790 OrderAccess::loadload();
791 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
792 "only fully initialized state can have a null lock");
793 return lock;
794 }
795
796 // Set the initialization lock to null so the object can be GC'ed. Any racing
797 // threads to get this lock will see a null lock and will not lock.
798 // That's okay because they all check for initialized state after getting
799 // the lock and return. For preempted vthreads we keep the oop protected
800 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()).
801 void InstanceKlass::fence_and_clear_init_lock() {
802 // make sure previous stores are all done, notably the init_state.
803 OrderAccess::storestore();
804 java_lang_Class::clear_init_lock(java_mirror());
805 assert(!is_not_initialized(), "class must be initialized now");
806 }
807
808 void InstanceKlass::initialize_preemptable(TRAPS) {
809 if (this->should_be_initialized()) {
810 PREEMPT_ON_INIT_SUPPORTED_ONLY(PreemptableInitCall pic(THREAD, this);)
811 initialize_impl(THREAD);
812 } else {
813 assert(is_initialized(), "sanity check");
814 }
815 }
816
817 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
818 // process. The step comments refers to the procedure described in that section.
819 // Note: implementation moved to static method to expose the this pointer.
820 void InstanceKlass::initialize(TRAPS) {
821 if (this->should_be_initialized()) {
822 initialize_impl(CHECK);
823 // Note: at this point the class may be initialized
824 // OR it may be in the state of being initialized
825 // in case of recursive initialization!
826 } else {
827 assert(is_initialized(), "sanity check");
828 }
829 }
830
831 #ifdef ASSERT
832 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
833 assert(has_aot_initialized_mirror(), "must be");
834
835 InstanceKlass* s = super();
836 if (s != nullptr) {
837 DEBUG_ONLY(ResourceMark rm);
838 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
839 s->external_name(), external_name());
840 s->assert_no_clinit_will_run_for_aot_initialized_class();
841 }
842
843 Array<InstanceKlass*>* interfaces = local_interfaces();
844 int len = interfaces->length();
845 for (int i = 0; i < len; i++) {
846 InstanceKlass* intf = interfaces->at(i);
847 if (!intf->is_initialized()) {
848 ResourceMark rm;
849 // Note: an interface needs to be marked as is_initialized() only if
850 // - it has a <clinit>
851 // - it has declared a default method.
852 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
853 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
854 intf->external_name(), external_name());
855 }
856 }
857 }
858 #endif
859
860 #if INCLUDE_CDS
861 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
862 assert(has_aot_initialized_mirror(), "must be");
863 assert(CDSConfig::is_loading_heap(), "must be");
864 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
865 assert_no_clinit_will_run_for_aot_initialized_class();
866
867 if (is_initialized()) {
868 return;
869 }
870
871 if (is_runtime_setup_required()) {
872 // Need to take the slow path, which will call the runtimeSetup() function instead
873 // of <clinit>
874 initialize(CHECK);
875 return;
876 }
877 if (log_is_enabled(Info, aot, init)) {
878 ResourceMark rm;
879 log_info(aot, init)("%s (aot-inited)", external_name());
880 }
881
882 link_class(CHECK);
883
884 #ifdef ASSERT
885 {
886 Handle h_init_lock(THREAD, init_lock());
887 ObjectLocker ol(h_init_lock, THREAD);
888 assert(!is_initialized(), "sanity");
889 assert(!is_being_initialized(), "sanity");
890 assert(!is_in_error_state(), "sanity");
891 }
892 #endif
893
894 set_init_thread(THREAD);
895 set_initialization_state_and_notify(fully_initialized, CHECK);
896 }
897 #endif
898
899 bool InstanceKlass::verify_code(TRAPS) {
900 // 1) Verify the bytecodes
901 return Verifier::verify(this, should_verify_class(), THREAD);
902 }
903
904 void InstanceKlass::link_class(TRAPS) {
905 assert(is_loaded(), "must be loaded");
906 if (!is_linked()) {
907 link_class_impl(CHECK);
908 }
909 }
910
911 // Called to verify that a class can link during initialization, without
912 // throwing a VerifyError.
913 bool InstanceKlass::link_class_or_fail(TRAPS) {
914 assert(is_loaded(), "must be loaded");
915 if (!is_linked()) {
916 link_class_impl(CHECK_false);
917 }
918 return is_linked();
919 }
920
921 bool InstanceKlass::link_class_impl(TRAPS) {
922 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
923 // This is for CDS static dump only -- we use the in_error_state to indicate that
924 // the class has failed verification. Throwing the NoClassDefFoundError here is just
925 // a convenient way to stop repeat attempts to verify the same (bad) class.
926 //
927 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
928 // if we are executing Java code. This is not a problem for CDS dumping phase since
929 // it doesn't execute any Java code.
930 ResourceMark rm(THREAD);
931 // Names are all known to be < 64k so we know this formatted message is not excessively large.
932 Exceptions::fthrow(THREAD_AND_LOCATION,
933 vmSymbols::java_lang_NoClassDefFoundError(),
934 "Class %s, or one of its supertypes, failed class initialization",
935 external_name());
936 return false;
937 }
938 // return if already verified
939 if (is_linked()) {
940 return true;
941 }
942
943 // Timing
944 // timer handles recursion
945 JavaThread* jt = THREAD;
946
947 // link super class before linking this class
948 InstanceKlass* super_klass = super();
949 if (super_klass != nullptr) {
950 if (super_klass->is_interface()) { // check if super class is an interface
951 ResourceMark rm(THREAD);
952 // Names are all known to be < 64k so we know this formatted message is not excessively large.
953 Exceptions::fthrow(
954 THREAD_AND_LOCATION,
955 vmSymbols::java_lang_IncompatibleClassChangeError(),
956 "class %s has interface %s as super class",
957 external_name(),
958 super_klass->external_name()
959 );
960 return false;
961 }
962
963 super_klass->link_class_impl(CHECK_false);
964 }
965
966 // link all interfaces implemented by this class before linking this class
967 Array<InstanceKlass*>* interfaces = local_interfaces();
968 int num_interfaces = interfaces->length();
969 for (int index = 0; index < num_interfaces; index++) {
970 InstanceKlass* interk = interfaces->at(index);
971 interk->link_class_impl(CHECK_false);
972 }
973
974 // in case the class is linked in the process of linking its superclasses
975 if (is_linked()) {
976 return true;
977 }
978
979 // trace only the link time for this klass that includes
980 // the verification time
981 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
982 ClassLoader::perf_class_link_selftime(),
983 ClassLoader::perf_classes_linked(),
984 jt->get_thread_stat()->perf_recursion_counts_addr(),
985 jt->get_thread_stat()->perf_timers_addr(),
986 PerfClassTraceTime::CLASS_LINK);
987
988 // verification & rewriting
989 {
990 HandleMark hm(THREAD);
991 Handle h_init_lock(THREAD, init_lock());
992 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false);
993 // Don't allow preemption if we link/initialize classes below,
994 // since that would release this monitor while we are in the
995 // middle of linking this class.
996 NoPreemptMark npm(THREAD);
997
998 // rewritten will have been set if loader constraint error found
999 // on an earlier link attempt
1000 // don't verify or rewrite if already rewritten
1001 //
1002
1003 if (!is_linked()) {
1004 if (!is_rewritten()) {
1005 if (in_aot_cache()) {
1006 assert(!verified_at_dump_time(), "must be");
1007 }
1008 {
1009 bool verify_ok = verify_code(THREAD);
1010 if (!verify_ok) {
1011 return false;
1012 }
1013 }
1014
1015 // Just in case a side-effect of verify linked this class already
1016 // (which can sometimes happen since the verifier loads classes
1017 // using custom class loaders, which are free to initialize things)
1018 if (is_linked()) {
1019 return true;
1020 }
1021
1022 // also sets rewritten
1023 rewrite_class(CHECK_false);
1024 } else if (in_aot_cache()) {
1025 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1026 }
1027
1028 // relocate jsrs and link methods after they are all rewritten
1029 link_methods(CHECK_false);
1030
1031 // Initialize the vtable and interface table after
1032 // methods have been rewritten since rewrite may
1033 // fabricate new Method*s.
1034 // also does loader constraint checking
1035 //
1036 // initialize_vtable and initialize_itable need to be rerun
1037 // for a shared class if
1038 // 1) the class is loaded by custom class loader or
1039 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1040 // 3) the class was not verified during dump time
1041 bool need_init_table = true;
1042 if (in_aot_cache() && verified_at_dump_time() &&
1043 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1044 need_init_table = false;
1045 }
1046 if (need_init_table) {
1047 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1048 itable().initialize_itable_and_check_constraints(CHECK_false);
1049 }
1050 #ifdef ASSERT
1051 vtable().verify(tty, true);
1052 // In case itable verification is ever added.
1053 // itable().verify(tty, true);
1054 #endif
1055 if (Universe::is_fully_initialized()) {
1056 DeoptimizationScope deopt_scope;
1057 {
1058 // Now mark all code that assumes the class is not linked.
1059 // Set state under the Compile_lock also.
1060 MutexLocker ml(THREAD, Compile_lock);
1061
1062 set_init_state(linked);
1063 CodeCache::mark_dependents_on(&deopt_scope, this);
1064 }
1065 // Perform the deopt handshake outside Compile_lock.
1066 deopt_scope.deoptimize_marked();
1067 } else {
1068 set_init_state(linked);
1069 }
1070 if (JvmtiExport::should_post_class_prepare()) {
1071 JvmtiExport::post_class_prepare(THREAD, this);
1072 }
1073 }
1074 }
1075 return true;
1076 }
1077
1078 // Rewrite the byte codes of all of the methods of a class.
1079 // The rewriter must be called exactly once. Rewriting must happen after
1080 // verification but before the first method of the class is executed.
1081 void InstanceKlass::rewrite_class(TRAPS) {
1082 assert(is_loaded(), "must be loaded");
1083 if (is_rewritten()) {
1084 assert(in_aot_cache(), "rewriting an unshared class?");
1085 return;
1086 }
1087 Rewriter::rewrite(this, CHECK);
1088 set_rewritten();
1089 }
1090
1091 // Now relocate and link method entry points after class is rewritten.
1092 // This is outside is_rewritten flag. In case of an exception, it can be
1093 // executed more than once.
1094 void InstanceKlass::link_methods(TRAPS) {
1095 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1096
1097 int len = methods()->length();
1098 for (int i = len-1; i >= 0; i--) {
1099 methodHandle m(THREAD, methods()->at(i));
1100
1101 // Set up method entry points for compiler and interpreter .
1102 m->link_method(m, CHECK);
1103 }
1104 }
1105
1106 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1107 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1108 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1109 for (int i = 0; i < local_interfaces()->length(); ++i) {
1110 InstanceKlass* ik = local_interfaces()->at(i);
1111
1112 // Initialization is depth first search ie. we start with top of the inheritance tree
1113 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1114 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1115 if (ik->has_nonstatic_concrete_methods()) {
1116 ik->initialize_super_interfaces(CHECK);
1117 }
1118
1119 // Only initialize() interfaces that "declare" concrete methods.
1120 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1121 ik->initialize(CHECK);
1122 }
1123 }
1124 }
1125
1126 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1127 static InitializationErrorTable* _initialization_error_table;
1128
1129 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1130 // Create the same exception with a message indicating the thread name,
1131 // and the StackTraceElements.
1132 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1133 ResourceMark rm(current);
1134 if (init_error.is_null()) {
1135 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1136
1137 // We failed to create the new exception, most likely due to either out-of-memory or
1138 // a stackoverflow error. If the original exception was either of those then we save
1139 // the shared, pre-allocated, stackless, instance of that exception.
1140 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1141 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1142 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1143 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1144 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1145 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1146 } else {
1147 return;
1148 }
1149 }
1150
1151 MutexLocker ml(current, ClassInitError_lock);
1152 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1153 bool created;
1154 if (_initialization_error_table == nullptr) {
1155 _initialization_error_table = new (mtClass) InitializationErrorTable();
1156 }
1157 _initialization_error_table->put_if_absent(this, elem, &created);
1158 assert(created, "Initialization is single threaded");
1159 log_trace(class, init)("Initialization error added for class %s", external_name());
1160 }
1161
1162 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1163 MutexLocker ml(current, ClassInitError_lock);
1164 if (_initialization_error_table == nullptr) {
1165 return nullptr;
1166 }
1167 OopHandle* h = _initialization_error_table->get(this);
1168 return (h != nullptr) ? h->resolve() : nullptr;
1169 }
1170
1171 // Need to remove entries for unloaded classes.
1172 void InstanceKlass::clean_initialization_error_table() {
1173 struct InitErrorTableCleaner {
1174 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1175 if (!ik->is_loader_alive()) {
1176 h.release(Universe::vm_global());
1177 return true;
1178 } else {
1179 return false;
1180 }
1181 }
1182 };
1183
1184 assert_locked_or_safepoint(ClassInitError_lock);
1185 InitErrorTableCleaner cleaner;
1186 if (_initialization_error_table != nullptr) {
1187 _initialization_error_table->unlink(&cleaner);
1188 }
1189 }
1190
1191 void InstanceKlass::initialize_impl(TRAPS) {
1192 HandleMark hm(THREAD);
1193
1194 // Make sure klass is linked (verified) before initialization
1195 // A class could already be verified, since it has been reflected upon.
1196 link_class(CHECK);
1197
1198 DTRACE_CLASSINIT_PROBE(required, -1);
1199
1200 bool wait = false;
1201
1202 JavaThread* jt = THREAD;
1203
1204 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1205
1206 // refer to the JVM book page 47 for description of steps
1207 // Step 1
1208 {
1209 Handle h_init_lock(THREAD, init_lock());
1210 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE);
1211
1212 // Step 2
1213 // If we were to use wait() instead of waitInterruptibly() then
1214 // we might end up throwing IE from link/symbol resolution sites
1215 // that aren't expected to throw. This would wreak havoc. See 6320309.
1216 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1217 if (debug_logging_enabled) {
1218 ResourceMark rm(jt);
1219 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1220 jt->name(), external_name(), init_thread_name());
1221 }
1222 wait = true;
1223 ThreadWaitingForClassInit twcl(THREAD, this);
1224 ol.wait_uninterruptibly(CHECK_PREEMPTABLE);
1225 }
1226
1227 // Step 3
1228 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1229 if (debug_logging_enabled) {
1230 ResourceMark rm(jt);
1231 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1232 jt->name(), external_name());
1233 }
1234 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1235 return;
1236 }
1237
1238 // Step 4
1239 if (is_initialized()) {
1240 if (debug_logging_enabled) {
1241 ResourceMark rm(jt);
1242 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1243 jt->name(), external_name());
1244 }
1245 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1246 return;
1247 }
1248
1249 // Step 5
1250 if (is_in_error_state()) {
1251 if (debug_logging_enabled) {
1252 ResourceMark rm(jt);
1253 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1254 jt->name(), external_name());
1255 }
1256
1257 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1258 ResourceMark rm(THREAD);
1259 Handle cause(THREAD, get_initialization_error(THREAD));
1260
1261 stringStream ss;
1262 ss.print("Could not initialize class %s", external_name());
1263 if (cause.is_null()) {
1264 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1265 } else {
1266 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1267 ss.as_string(), cause);
1268 }
1269 } else {
1270
1271 // Step 6
1272 set_init_state(being_initialized);
1273 set_init_thread(jt);
1274 if (debug_logging_enabled) {
1275 ResourceMark rm(jt);
1276 log_debug(class, init)("Thread \"%s\" is initializing %s",
1277 jt->name(), external_name());
1278 }
1279 }
1280 }
1281
1282 // Block preemption once we are the initializer thread. Unmounting now
1283 // would complicate the reentrant case (identity is platform thread).
1284 NoPreemptMark npm(THREAD);
1285
1286 // Step 7
1287 // Next, if C is a class rather than an interface, initialize it's super class and super
1288 // interfaces.
1289 if (!is_interface()) {
1290 Klass* super_klass = super();
1291 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1292 super_klass->initialize(THREAD);
1293 }
1294 // If C implements any interface that declares a non-static, concrete method,
1295 // the initialization of C triggers initialization of its super interfaces.
1296 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1297 // having a superinterface that declares, non-static, concrete methods
1298 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1299 initialize_super_interfaces(THREAD);
1300 }
1301
1302 // If any exceptions, complete abruptly, throwing the same exception as above.
1303 if (HAS_PENDING_EXCEPTION) {
1304 Handle e(THREAD, PENDING_EXCEPTION);
1305 CLEAR_PENDING_EXCEPTION;
1306 {
1307 EXCEPTION_MARK;
1308 add_initialization_error(THREAD, e);
1309 // Locks object, set state, and notify all waiting threads
1310 set_initialization_state_and_notify(initialization_error, THREAD);
1311 CLEAR_PENDING_EXCEPTION;
1312 }
1313 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1314 THROW_OOP(e());
1315 }
1316 }
1317
1318
1319 // Step 8
1320 {
1321 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1322 if (class_initializer() != nullptr) {
1323 // Timer includes any side effects of class initialization (resolution,
1324 // etc), but not recursive entry into call_class_initializer().
1325 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1326 ClassLoader::perf_class_init_selftime(),
1327 ClassLoader::perf_classes_inited(),
1328 jt->get_thread_stat()->perf_recursion_counts_addr(),
1329 jt->get_thread_stat()->perf_timers_addr(),
1330 PerfClassTraceTime::CLASS_CLINIT);
1331 call_class_initializer(THREAD);
1332 } else {
1333 // The elapsed time is so small it's not worth counting.
1334 if (UsePerfData) {
1335 ClassLoader::perf_classes_inited()->inc();
1336 }
1337 call_class_initializer(THREAD);
1338 }
1339 }
1340
1341 // Step 9
1342 if (!HAS_PENDING_EXCEPTION) {
1343 set_initialization_state_and_notify(fully_initialized, CHECK);
1344 DEBUG_ONLY(vtable().verify(tty, true);)
1345 CompilationPolicy::replay_training_at_init(this, THREAD);
1346 }
1347 else {
1348 // Step 10 and 11
1349 Handle e(THREAD, PENDING_EXCEPTION);
1350 CLEAR_PENDING_EXCEPTION;
1351 // JVMTI has already reported the pending exception
1352 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1353 JvmtiExport::clear_detected_exception(jt);
1354 {
1355 EXCEPTION_MARK;
1356 add_initialization_error(THREAD, e);
1357 set_initialization_state_and_notify(initialization_error, THREAD);
1358 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1359 // JVMTI has already reported the pending exception
1360 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1361 JvmtiExport::clear_detected_exception(jt);
1362 }
1363 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1364 if (e->is_a(vmClasses::Error_klass())) {
1365 THROW_OOP(e());
1366 } else {
1367 JavaCallArguments args(e);
1368 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1369 vmSymbols::throwable_void_signature(),
1370 &args);
1371 }
1372 }
1373 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1374 }
1375
1376
1377 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1378 Handle h_init_lock(THREAD, init_lock());
1379 if (h_init_lock() != nullptr) {
1380 ObjectLocker ol(h_init_lock, THREAD);
1381 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1382 set_init_state(state);
1383 fence_and_clear_init_lock();
1384 ol.notify_all(CHECK);
1385 } else {
1386 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1387 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1388 set_init_state(state);
1389 }
1390 }
1391
1392 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1393 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1394 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1395 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1396
1397 DeoptimizationScope deopt_scope;
1398 {
1399 MutexLocker ml(current, Compile_lock);
1400
1401 set_init_state(InstanceKlass::loaded);
1402 // make sure init_state store is already done.
1403 // The compiler reads the hierarchy outside of the Compile_lock.
1404 // Access ordering is used to add to hierarchy.
1405
1406 // Link into hierarchy.
1407 append_to_sibling_list(); // add to superklass/sibling list
1408 process_interfaces(); // handle all "implements" declarations
1409
1410 // Now mark all code that depended on old class hierarchy.
1411 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1412 if (Universe::is_fully_initialized()) {
1413 CodeCache::mark_dependents_on(&deopt_scope, this);
1414 }
1415 }
1416 // Perform the deopt handshake outside Compile_lock.
1417 deopt_scope.deoptimize_marked();
1418 }
1419
1420
1421 InstanceKlass* InstanceKlass::implementor() const {
1422 InstanceKlass* volatile* ik = adr_implementor();
1423 if (ik == nullptr) {
1424 return nullptr;
1425 } else {
1426 // This load races with inserts, and therefore needs acquire.
1427 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1428 if (ikls != nullptr && !ikls->is_loader_alive()) {
1429 return nullptr; // don't return unloaded class
1430 } else {
1431 return ikls;
1432 }
1433 }
1434 }
1435
1436
1437 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1438 assert_locked_or_safepoint(Compile_lock);
1439 assert(is_interface(), "not interface");
1440 InstanceKlass* volatile* addr = adr_implementor();
1441 assert(addr != nullptr, "null addr");
1442 if (addr != nullptr) {
1443 AtomicAccess::release_store(addr, ik);
1444 }
1445 }
1446
1447 int InstanceKlass::nof_implementors() const {
1448 InstanceKlass* ik = implementor();
1449 if (ik == nullptr) {
1450 return 0;
1451 } else if (ik != this) {
1452 return 1;
1453 } else {
1454 return 2;
1455 }
1456 }
1457
1458 // The embedded _implementor field can only record one implementor.
1459 // When there are more than one implementors, the _implementor field
1460 // is set to the interface Klass* itself. Following are the possible
1461 // values for the _implementor field:
1462 // null - no implementor
1463 // implementor Klass* - one implementor
1464 // self - more than one implementor
1465 //
1466 // The _implementor field only exists for interfaces.
1467 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1468 if (Universe::is_fully_initialized()) {
1469 assert_lock_strong(Compile_lock);
1470 }
1471 assert(is_interface(), "not interface");
1472 // Filter out my subinterfaces.
1473 // (Note: Interfaces are never on the subklass list.)
1474 if (ik->is_interface()) return;
1475
1476 // Filter out subclasses whose supers already implement me.
1477 // (Note: CHA must walk subclasses of direct implementors
1478 // in order to locate indirect implementors.)
1479 InstanceKlass* super_ik = ik->super();
1480 if (super_ik != nullptr && super_ik->implements_interface(this))
1481 // We only need to check one immediate superclass, since the
1482 // implements_interface query looks at transitive_interfaces.
1483 // Any supers of the super have the same (or fewer) transitive_interfaces.
1484 return;
1485
1486 InstanceKlass* iklass = implementor();
1487 if (iklass == nullptr) {
1488 set_implementor(ik);
1489 } else if (iklass != this && iklass != ik) {
1490 // There is already an implementor. Use itself as an indicator of
1491 // more than one implementors.
1492 set_implementor(this);
1493 }
1494
1495 // The implementor also implements the transitive_interfaces
1496 for (int index = 0; index < local_interfaces()->length(); index++) {
1497 local_interfaces()->at(index)->add_implementor(ik);
1498 }
1499 }
1500
1501 void InstanceKlass::init_implementor() {
1502 if (is_interface()) {
1503 set_implementor(nullptr);
1504 }
1505 }
1506
1507
1508 void InstanceKlass::process_interfaces() {
1509 // link this class into the implementors list of every interface it implements
1510 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1511 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1512 InstanceKlass* interf = local_interfaces()->at(i);
1513 assert(interf->is_interface(), "expected interface");
1514 interf->add_implementor(this);
1515 }
1516 }
1517
1518 bool InstanceKlass::can_be_primary_super_slow() const {
1519 if (is_interface())
1520 return false;
1521 else
1522 return Klass::can_be_primary_super_slow();
1523 }
1524
1525 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1526 Array<InstanceKlass*>* transitive_interfaces) {
1527 // The secondaries are the implemented interfaces.
1528 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1529 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1530 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1531 int num_secondaries = num_extra_slots + interfaces->length();
1532 if (num_secondaries == 0) {
1533 // Must share this for correct bootstrapping!
1534 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1535 return nullptr;
1536 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1537 // We will reuse the transitive interfaces list if we're certain
1538 // it's in hash order.
1539 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1540 set_secondary_supers(interfaces, bitmap);
1541 return nullptr;
1542 }
1543 // Copy transitive interfaces to a temporary growable array to be constructed
1544 // into the secondary super list with extra slots.
1545 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1546 for (int i = 0; i < interfaces->length(); i++) {
1547 secondaries->push(interfaces->at(i));
1548 }
1549 return secondaries;
1550 }
1551
1552 bool InstanceKlass::implements_interface(Klass* k) const {
1553 if (this == k) return true;
1554 assert(k->is_interface(), "should be an interface class");
1555 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1556 if (transitive_interfaces()->at(i) == k) {
1557 return true;
1558 }
1559 }
1560 return false;
1561 }
1562
1563 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1564 // Verify direct super interface
1565 if (this == k) return true;
1566 assert(k->is_interface(), "should be an interface class");
1567 for (int i = 0; i < local_interfaces()->length(); i++) {
1568 if (local_interfaces()->at(i) == k) {
1569 return true;
1570 }
1571 }
1572 return false;
1573 }
1574
1575 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1576 if (TraceFinalizerRegistration) {
1577 tty->print("Registered ");
1578 i->print_value_on(tty);
1579 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1580 }
1581 instanceHandle h_i(THREAD, i);
1582 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1583 JavaValue result(T_VOID);
1584 JavaCallArguments args(h_i);
1585 methodHandle mh(THREAD, Universe::finalizer_register_method());
1586 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1587 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1588 return h_i();
1589 }
1590
1591 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1592 assert(!is_abstract() && !is_interface(), "Should not create this object");
1593 size_t size = size_helper(); // Query before forming handle.
1594 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1595 }
1596
1597 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1598 Klass* k = java_lang_Class::as_Klass(java_class);
1599 if (k == nullptr) {
1600 ResourceMark rm(THREAD);
1601 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1602 }
1603 InstanceKlass* ik = cast(k);
1604 ik->check_valid_for_instantiation(false, CHECK_NULL);
1605 ik->initialize(CHECK_NULL);
1606 return ik->allocate_instance(THREAD);
1607 }
1608
1609 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1610 return instanceHandle(THREAD, allocate_instance(THREAD));
1611 }
1612
1613 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1614 if (is_interface() || is_abstract()) {
1615 ResourceMark rm(THREAD);
1616 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1617 : vmSymbols::java_lang_InstantiationException(), external_name());
1618 }
1619 if (this == vmClasses::Class_klass()) {
1620 ResourceMark rm(THREAD);
1621 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1622 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1623 }
1624 }
1625
1626 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1627 // Need load-acquire for lock-free read
1628 if (array_klasses_acquire() == nullptr) {
1629
1630 // Recursively lock array allocation
1631 RecursiveLocker rl(MultiArray_lock, THREAD);
1632
1633 // Check if another thread created the array klass while we were waiting for the lock.
1634 if (array_klasses() == nullptr) {
1635 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1636 // use 'release' to pair with lock-free load
1637 release_set_array_klasses(k);
1638 }
1639 }
1640
1641 // array_klasses() will always be set at this point
1642 ObjArrayKlass* ak = array_klasses();
1643 assert(ak != nullptr, "should be set");
1644 return ak->array_klass(n, THREAD);
1645 }
1646
1647 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1648 // Need load-acquire for lock-free read
1649 ObjArrayKlass* oak = array_klasses_acquire();
1650 if (oak == nullptr) {
1651 return nullptr;
1652 } else {
1653 return oak->array_klass_or_null(n);
1654 }
1655 }
1656
1657 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1658 return array_klass(1, THREAD);
1659 }
1660
1661 ArrayKlass* InstanceKlass::array_klass_or_null() {
1662 return array_klass_or_null(1);
1663 }
1664
1665 static int call_class_initializer_counter = 0; // for debugging
1666
1667 Method* InstanceKlass::class_initializer() const {
1668 Method* clinit = find_method(
1669 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1670 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1671 return clinit;
1672 }
1673 return nullptr;
1674 }
1675
1676 void InstanceKlass::call_class_initializer(TRAPS) {
1677 if (ReplayCompiles &&
1678 (ReplaySuppressInitializers == 1 ||
1679 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1680 // Hide the existence of the initializer for the purpose of replaying the compile
1681 return;
1682 }
1683
1684 #if INCLUDE_CDS
1685 // This is needed to ensure the consistency of the archived heap objects.
1686 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1687 AOTClassInitializer::call_runtime_setup(THREAD, this);
1688 return;
1689 } else if (has_archived_enum_objs()) {
1690 assert(in_aot_cache(), "must be");
1691 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1692 if (initialized) {
1693 return;
1694 }
1695 }
1696 #endif
1697
1698 methodHandle h_method(THREAD, class_initializer());
1699 assert(!is_initialized(), "we cannot initialize twice");
1700 LogTarget(Info, class, init) lt;
1701 if (lt.is_enabled()) {
1702 ResourceMark rm(THREAD);
1703 LogStream ls(lt);
1704 ls.print("%d Initializing ", call_class_initializer_counter++);
1705 name()->print_value_on(&ls);
1706 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1707 h_method() == nullptr ? "(no method)" : "", p2i(this),
1708 THREAD->name());
1709 }
1710 if (h_method() != nullptr) {
1711 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1712 JavaCallArguments args; // No arguments
1713 JavaValue result(T_VOID);
1714 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1715 }
1716 }
1717
1718 // If a class that implements this interface is initialized, is the JVM required
1719 // to first execute a <clinit> method declared in this interface,
1720 // or (if also_check_supers==true) any of the super types of this interface?
1721 //
1722 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1723 // an interface, then let SC be its superclass and let SI1, ..., SIn
1724 // be all superinterfaces of C (whether direct or indirect) that
1725 // declare at least one non-abstract, non-static method.
1726 //
1727 // So when an interface is initialized, it does not look at its
1728 // supers. But a proper class will ensure that all of its supers have
1729 // run their <clinit> methods, except that it disregards interfaces
1730 // that lack a non-static concrete method (i.e., a default method).
1731 // Therefore, you should probably call this method only when the
1732 // current class is a super of some proper class, not an interface.
1733 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1734 assert(is_interface(), "must be");
1735
1736 if (!has_nonstatic_concrete_methods()) {
1737 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1738 return false;
1739 }
1740
1741 // JVMS 5.5. Initialization
1742 // ...If C is an interface that declares a non-abstract,
1743 // non-static method, the initialization of a class that
1744 // implements C directly or indirectly.
1745 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1746 return true;
1747 }
1748 if (also_check_supers) {
1749 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1750 for (int i = 0; i < all_ifs->length(); ++i) {
1751 InstanceKlass* super_intf = all_ifs->at(i);
1752 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1753 return true;
1754 }
1755 }
1756 }
1757 return false;
1758 }
1759
1760 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1761 InterpreterOopMap* entry_for) {
1762 // Lazily create the _oop_map_cache at first request.
1763 // Load_acquire is needed to safely get instance published with CAS by another thread.
1764 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
1765 if (oop_map_cache == nullptr) {
1766 // Try to install new instance atomically.
1767 oop_map_cache = new OopMapCache();
1768 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1769 if (other != nullptr) {
1770 // Someone else managed to install before us, ditch local copy and use the existing one.
1771 delete oop_map_cache;
1772 oop_map_cache = other;
1773 }
1774 }
1775 // _oop_map_cache is constant after init; lookup below does its own locking.
1776 oop_map_cache->lookup(method, bci, entry_for);
1777 }
1778
1779 bool InstanceKlass::contains_field_offset(int offset) {
1780 fieldDescriptor fd;
1781 return find_field_from_offset(offset, false, &fd);
1782 }
1783
1784 FieldInfo InstanceKlass::field(int index) const {
1785 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1786 if (fs.index() == index) {
1787 return fs.to_FieldInfo();
1788 }
1789 }
1790 fatal("Field not found");
1791 return FieldInfo();
1792 }
1793
1794 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1795 JavaFieldStream fs(this);
1796 if (fs.lookup(name, sig)) {
1797 assert(fs.name() == name, "name must match");
1798 assert(fs.signature() == sig, "signature must match");
1799 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1800 return true;
1801 }
1802 return false;
1803 }
1804
1805
1806 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1807 const int n = local_interfaces()->length();
1808 for (int i = 0; i < n; i++) {
1809 InstanceKlass* intf1 = local_interfaces()->at(i);
1810 assert(intf1->is_interface(), "just checking type");
1811 // search for field in current interface
1812 if (intf1->find_local_field(name, sig, fd)) {
1813 assert(fd->is_static(), "interface field must be static");
1814 return intf1;
1815 }
1816 // search for field in direct superinterfaces
1817 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
1818 if (intf2 != nullptr) return intf2;
1819 }
1820 // otherwise field lookup fails
1821 return nullptr;
1822 }
1823
1824
1825 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1826 // search order according to newest JVM spec (5.4.3.2, p.167).
1827 // 1) search for field in current klass
1828 if (find_local_field(name, sig, fd)) {
1829 return const_cast<InstanceKlass*>(this);
1830 }
1831 // 2) search for field recursively in direct superinterfaces
1832 { Klass* intf = find_interface_field(name, sig, fd);
1833 if (intf != nullptr) return intf;
1834 }
1835 // 3) apply field lookup recursively if superclass exists
1836 { InstanceKlass* supr = super();
1837 if (supr != nullptr) return supr->find_field(name, sig, fd);
1838 }
1839 // 4) otherwise field lookup fails
1840 return nullptr;
1841 }
1842
1843
1844 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1845 // search order according to newest JVM spec (5.4.3.2, p.167).
1846 // 1) search for field in current klass
1847 if (find_local_field(name, sig, fd)) {
1848 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1849 }
1850 // 2) search for field recursively in direct superinterfaces
1851 if (is_static) {
1852 Klass* intf = find_interface_field(name, sig, fd);
1853 if (intf != nullptr) return intf;
1854 }
1855 // 3) apply field lookup recursively if superclass exists
1856 { InstanceKlass* supr = super();
1857 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
1858 }
1859 // 4) otherwise field lookup fails
1860 return nullptr;
1861 }
1862
1863
1864 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1865 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1866 if (fs.offset() == offset) {
1867 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1868 if (fd->is_static() == is_static) return true;
1869 }
1870 }
1871 return false;
1872 }
1873
1874
1875 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1876 const InstanceKlass* klass = this;
1877 while (klass != nullptr) {
1878 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
1879 return true;
1880 }
1881 klass = klass->super();
1882 }
1883 return false;
1884 }
1885
1886
1887 void InstanceKlass::methods_do(void f(Method* method)) {
1888 // Methods aren't stable until they are loaded. This can be read outside
1889 // a lock through the ClassLoaderData for profiling
1890 // Redefined scratch classes are on the list and need to be cleaned
1891 if (!is_loaded() && !is_scratch_class()) {
1892 return;
1893 }
1894
1895 int len = methods()->length();
1896 for (int index = 0; index < len; index++) {
1897 Method* m = methods()->at(index);
1898 assert(m->is_method(), "must be method");
1899 f(m);
1900 }
1901 }
1902
1903
1904 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1905 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1906 if (fs.access_flags().is_static()) {
1907 fieldDescriptor& fd = fs.field_descriptor();
1908 cl->do_field(&fd);
1909 }
1910 }
1911 }
1912
1913
1914 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1915 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1916 if (fs.access_flags().is_static()) {
1917 fieldDescriptor& fd = fs.field_descriptor();
1918 f(&fd, mirror, CHECK);
1919 }
1920 }
1921 }
1922
1923 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1924 InstanceKlass* super = this->super();
1925 if (super != nullptr) {
1926 super->do_nonstatic_fields(cl);
1927 }
1928 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1929 fieldDescriptor& fd = fs.field_descriptor();
1930 if (!fd.is_static()) {
1931 cl->do_field(&fd);
1932 }
1933 }
1934 }
1935
1936 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
1937 return a->offset() - b->offset();
1938 }
1939
1940 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1941 InstanceKlass* super = this->super();
1942 if (super != nullptr) {
1943 super->print_nonstatic_fields(cl);
1944 }
1945 ResourceMark rm;
1946 // In DebugInfo nonstatic fields are sorted by offset.
1947 GrowableArray<FieldInfo> fields_sorted;
1948 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1949 if (!fs.access_flags().is_static()) {
1950 fields_sorted.push(fs.to_FieldInfo());
1951 }
1952 }
1953 int length = fields_sorted.length();
1954 if (length > 0) {
1955 fields_sorted.sort(compare_fields_by_offset);
1956 fieldDescriptor fd;
1957 for (int i = 0; i < length; i++) {
1958 fd.reinitialize(this, fields_sorted.at(i));
1959 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
1960 cl->do_field(&fd);
1961 }
1962 }
1963 }
1964
1965 #ifdef ASSERT
1966 static int linear_search(const Array<Method*>* methods,
1967 const Symbol* name,
1968 const Symbol* signature) {
1969 const int len = methods->length();
1970 for (int index = 0; index < len; index++) {
1971 const Method* const m = methods->at(index);
1972 assert(m->is_method(), "must be method");
1973 if (m->signature() == signature && m->name() == name) {
1974 return index;
1975 }
1976 }
1977 return -1;
1978 }
1979 #endif
1980
1981 bool InstanceKlass::_disable_method_binary_search = false;
1982
1983 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1984 int len = methods->length();
1985 int l = 0;
1986 int h = len - 1;
1987 while (l <= h) {
1988 Method* m = methods->at(l);
1989 if (m->name() == name) {
1990 return l;
1991 }
1992 l++;
1993 }
1994 return -1;
1995 }
1996
1997 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1998 if (_disable_method_binary_search) {
1999 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2000 // At the final stage of dynamic dumping, the methods array may not be sorted
2001 // by ascending addresses of their names, so we can't use binary search anymore.
2002 // However, methods with the same name are still laid out consecutively inside the
2003 // methods array, so let's look for the first one that matches.
2004 return linear_search(methods, name);
2005 }
2006
2007 int len = methods->length();
2008 int l = 0;
2009 int h = len - 1;
2010
2011 // methods are sorted by ascending addresses of their names, so do binary search
2012 while (l <= h) {
2013 int mid = (l + h) >> 1;
2014 Method* m = methods->at(mid);
2015 assert(m->is_method(), "must be method");
2016 int res = m->name()->fast_compare(name);
2017 if (res == 0) {
2018 return mid;
2019 } else if (res < 0) {
2020 l = mid + 1;
2021 } else {
2022 h = mid - 1;
2023 }
2024 }
2025 return -1;
2026 }
2027
2028 // find_method looks up the name/signature in the local methods array
2029 Method* InstanceKlass::find_method(const Symbol* name,
2030 const Symbol* signature) const {
2031 return find_method_impl(name, signature,
2032 OverpassLookupMode::find,
2033 StaticLookupMode::find,
2034 PrivateLookupMode::find);
2035 }
2036
2037 Method* InstanceKlass::find_method_impl(const Symbol* name,
2038 const Symbol* signature,
2039 OverpassLookupMode overpass_mode,
2040 StaticLookupMode static_mode,
2041 PrivateLookupMode private_mode) const {
2042 return InstanceKlass::find_method_impl(methods(),
2043 name,
2044 signature,
2045 overpass_mode,
2046 static_mode,
2047 private_mode);
2048 }
2049
2050 // find_instance_method looks up the name/signature in the local methods array
2051 // and skips over static methods
2052 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2053 const Symbol* name,
2054 const Symbol* signature,
2055 PrivateLookupMode private_mode) {
2056 Method* const meth = InstanceKlass::find_method_impl(methods,
2057 name,
2058 signature,
2059 OverpassLookupMode::find,
2060 StaticLookupMode::skip,
2061 private_mode);
2062 assert(((meth == nullptr) || !meth->is_static()),
2063 "find_instance_method should have skipped statics");
2064 return meth;
2065 }
2066
2067 // find_instance_method looks up the name/signature in the local methods array
2068 // and skips over static methods
2069 Method* InstanceKlass::find_instance_method(const Symbol* name,
2070 const Symbol* signature,
2071 PrivateLookupMode private_mode) const {
2072 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2073 }
2074
2075 // Find looks up the name/signature in the local methods array
2076 // and filters on the overpass, static and private flags
2077 // This returns the first one found
2078 // note that the local methods array can have up to one overpass, one static
2079 // and one instance (private or not) with the same name/signature
2080 Method* InstanceKlass::find_local_method(const Symbol* name,
2081 const Symbol* signature,
2082 OverpassLookupMode overpass_mode,
2083 StaticLookupMode static_mode,
2084 PrivateLookupMode private_mode) const {
2085 return InstanceKlass::find_method_impl(methods(),
2086 name,
2087 signature,
2088 overpass_mode,
2089 static_mode,
2090 private_mode);
2091 }
2092
2093 // Find looks up the name/signature in the local methods array
2094 // and filters on the overpass, static and private flags
2095 // This returns the first one found
2096 // note that the local methods array can have up to one overpass, one static
2097 // and one instance (private or not) with the same name/signature
2098 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2099 const Symbol* name,
2100 const Symbol* signature,
2101 OverpassLookupMode overpass_mode,
2102 StaticLookupMode static_mode,
2103 PrivateLookupMode private_mode) {
2104 return InstanceKlass::find_method_impl(methods,
2105 name,
2106 signature,
2107 overpass_mode,
2108 static_mode,
2109 private_mode);
2110 }
2111
2112 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2113 const Symbol* name,
2114 const Symbol* signature) {
2115 return InstanceKlass::find_method_impl(methods,
2116 name,
2117 signature,
2118 OverpassLookupMode::find,
2119 StaticLookupMode::find,
2120 PrivateLookupMode::find);
2121 }
2122
2123 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2124 const Symbol* name,
2125 const Symbol* signature,
2126 OverpassLookupMode overpass_mode,
2127 StaticLookupMode static_mode,
2128 PrivateLookupMode private_mode) {
2129 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2130 return hit >= 0 ? methods->at(hit): nullptr;
2131 }
2132
2133 // true if method matches signature and conforms to skipping_X conditions.
2134 static bool method_matches(const Method* m,
2135 const Symbol* signature,
2136 bool skipping_overpass,
2137 bool skipping_static,
2138 bool skipping_private) {
2139 return ((m->signature() == signature) &&
2140 (!skipping_overpass || !m->is_overpass()) &&
2141 (!skipping_static || !m->is_static()) &&
2142 (!skipping_private || !m->is_private()));
2143 }
2144
2145 // Used directly for default_methods to find the index into the
2146 // default_vtable_indices, and indirectly by find_method
2147 // find_method_index looks in the local methods array to return the index
2148 // of the matching name/signature. If, overpass methods are being ignored,
2149 // the search continues to find a potential non-overpass match. This capability
2150 // is important during method resolution to prefer a static method, for example,
2151 // over an overpass method.
2152 // There is the possibility in any _method's array to have the same name/signature
2153 // for a static method, an overpass method and a local instance method
2154 // To correctly catch a given method, the search criteria may need
2155 // to explicitly skip the other two. For local instance methods, it
2156 // is often necessary to skip private methods
2157 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2158 const Symbol* name,
2159 const Symbol* signature,
2160 OverpassLookupMode overpass_mode,
2161 StaticLookupMode static_mode,
2162 PrivateLookupMode private_mode) {
2163 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2164 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2165 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2166 const int hit = quick_search(methods, name);
2167 if (hit != -1) {
2168 const Method* const m = methods->at(hit);
2169
2170 // Do linear search to find matching signature. First, quick check
2171 // for common case, ignoring overpasses if requested.
2172 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2173 return hit;
2174 }
2175
2176 // search downwards through overloaded methods
2177 int i;
2178 for (i = hit - 1; i >= 0; --i) {
2179 const Method* const m = methods->at(i);
2180 assert(m->is_method(), "must be method");
2181 if (m->name() != name) {
2182 break;
2183 }
2184 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2185 return i;
2186 }
2187 }
2188 // search upwards
2189 for (i = hit + 1; i < methods->length(); ++i) {
2190 const Method* const m = methods->at(i);
2191 assert(m->is_method(), "must be method");
2192 if (m->name() != name) {
2193 break;
2194 }
2195 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2196 return i;
2197 }
2198 }
2199 // not found
2200 #ifdef ASSERT
2201 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2202 linear_search(methods, name, signature);
2203 assert(-1 == index, "binary search should have found entry %d", index);
2204 #endif
2205 }
2206 return -1;
2207 }
2208
2209 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2210 return find_method_by_name(methods(), name, end);
2211 }
2212
2213 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2214 const Symbol* name,
2215 int* end_ptr) {
2216 assert(end_ptr != nullptr, "just checking");
2217 int start = quick_search(methods, name);
2218 int end = start + 1;
2219 if (start != -1) {
2220 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2221 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2222 *end_ptr = end;
2223 return start;
2224 }
2225 return -1;
2226 }
2227
2228 // uncached_lookup_method searches both the local class methods array and all
2229 // superclasses methods arrays, skipping any overpass methods in superclasses,
2230 // and possibly skipping private methods.
2231 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2232 const Symbol* signature,
2233 OverpassLookupMode overpass_mode,
2234 PrivateLookupMode private_mode) const {
2235 OverpassLookupMode overpass_local_mode = overpass_mode;
2236 const InstanceKlass* klass = this;
2237 while (klass != nullptr) {
2238 Method* const method = klass->find_method_impl(name,
2239 signature,
2240 overpass_local_mode,
2241 StaticLookupMode::find,
2242 private_mode);
2243 if (method != nullptr) {
2244 return method;
2245 }
2246 klass = klass->super();
2247 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2248 }
2249 return nullptr;
2250 }
2251
2252 #ifdef ASSERT
2253 // search through class hierarchy and return true if this class or
2254 // one of the superclasses was redefined
2255 bool InstanceKlass::has_redefined_this_or_super() const {
2256 const InstanceKlass* klass = this;
2257 while (klass != nullptr) {
2258 if (klass->has_been_redefined()) {
2259 return true;
2260 }
2261 klass = klass->super();
2262 }
2263 return false;
2264 }
2265 #endif
2266
2267 // lookup a method in the default methods list then in all transitive interfaces
2268 // Do NOT return private or static methods
2269 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2270 Symbol* signature) const {
2271 Method* m = nullptr;
2272 if (default_methods() != nullptr) {
2273 m = find_method(default_methods(), name, signature);
2274 }
2275 // Look up interfaces
2276 if (m == nullptr) {
2277 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2278 }
2279 return m;
2280 }
2281
2282 // lookup a method in all the interfaces that this class implements
2283 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2284 // They should only be found in the initial InterfaceMethodRef
2285 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2286 Symbol* signature,
2287 DefaultsLookupMode defaults_mode) const {
2288 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2289 int num_ifs = all_ifs->length();
2290 InstanceKlass *ik = nullptr;
2291 for (int i = 0; i < num_ifs; i++) {
2292 ik = all_ifs->at(i);
2293 Method* m = ik->lookup_method(name, signature);
2294 if (m != nullptr && m->is_public() && !m->is_static() &&
2295 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2296 return m;
2297 }
2298 }
2299 return nullptr;
2300 }
2301
2302 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2303 :_st(st), _verbose(verbose) {
2304 ResourceMark rm;
2305 _st->print("%-18s ", "KlassAddr");
2306 _st->print("%-4s ", "Size");
2307 _st->print("%-20s ", "State");
2308 _st->print("%-7s ", "Flags");
2309 _st->print("%-5s ", "ClassName");
2310 _st->cr();
2311 }
2312
2313 void PrintClassClosure::do_klass(Klass* k) {
2314 ResourceMark rm;
2315 // klass pointer
2316 _st->print(PTR_FORMAT " ", p2i(k));
2317 // klass size
2318 _st->print("%4d ", k->size());
2319 // initialization state
2320 if (k->is_instance_klass()) {
2321 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2322 } else {
2323 _st->print("%-20s ","");
2324 }
2325 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2326 char buf[10];
2327 int i = 0;
2328 if (k->has_finalizer()) buf[i++] = 'F';
2329 if (k->is_instance_klass()) {
2330 InstanceKlass* ik = InstanceKlass::cast(k);
2331 if (ik->has_final_method()) buf[i++] = 'f';
2332 if (ik->is_rewritten()) buf[i++] = 'W';
2333 if (ik->is_contended()) buf[i++] = 'C';
2334 if (ik->has_been_redefined()) buf[i++] = 'R';
2335 if (ik->in_aot_cache()) buf[i++] = 'S';
2336 }
2337 buf[i++] = '\0';
2338 _st->print("%-7s ", buf);
2339 // klass name
2340 _st->print("%-5s ", k->external_name());
2341 // end
2342 _st->cr();
2343 if (_verbose) {
2344 k->print_on(_st);
2345 }
2346 }
2347
2348 /* jni_id_for for jfieldIds only */
2349 JNIid* InstanceKlass::jni_id_for(int offset) {
2350 MutexLocker ml(JfieldIdCreation_lock);
2351 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2352 if (probe == nullptr) {
2353 // Allocate new static field identifier
2354 probe = new JNIid(this, offset, jni_ids());
2355 set_jni_ids(probe);
2356 }
2357 return probe;
2358 }
2359
2360 u2 InstanceKlass::enclosing_method_data(int offset) const {
2361 const Array<jushort>* const inner_class_list = inner_classes();
2362 if (inner_class_list == nullptr) {
2363 return 0;
2364 }
2365 const int length = inner_class_list->length();
2366 if (length % inner_class_next_offset == 0) {
2367 return 0;
2368 }
2369 const int index = length - enclosing_method_attribute_size;
2370 assert(offset < enclosing_method_attribute_size, "invalid offset");
2371 return inner_class_list->at(index + offset);
2372 }
2373
2374 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2375 u2 method_index) {
2376 Array<jushort>* inner_class_list = inner_classes();
2377 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2378 int length = inner_class_list->length();
2379 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2380 int index = length - enclosing_method_attribute_size;
2381 inner_class_list->at_put(
2382 index + enclosing_method_class_index_offset, class_index);
2383 inner_class_list->at_put(
2384 index + enclosing_method_method_index_offset, method_index);
2385 }
2386 }
2387
2388 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2389 if (method->is_old() && !method->is_obsolete()) {
2390 // If the method passed in is old (but not obsolete), use the current version.
2391 method = method_with_idnum((int)idnum);
2392 assert(method != nullptr, "old and but not obsolete, so should exist");
2393 }
2394 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2395 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2396 return new_id;
2397 }
2398
2399 // Allocate the jmethodID cache.
2400 static jmethodID* create_jmethod_id_cache(size_t size) {
2401 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2402 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2403 // cache size is stored in element[0], other elements offset by one
2404 jmeths[0] = (jmethodID)size;
2405 return jmeths;
2406 }
2407
2408 // When reading outside a lock, use this.
2409 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2410 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2411 }
2412
2413 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2414 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2415 }
2416
2417 // Lookup or create a jmethodID.
2418 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2419 int idnum = method->method_idnum();
2420 jmethodID* jmeths = methods_jmethod_ids_acquire();
2421
2422 // We use a double-check locking idiom here because this cache is
2423 // performance sensitive. In the normal system, this cache only
2424 // transitions from null to non-null which is safe because we use
2425 // release_set_methods_jmethod_ids() to advertise the new cache.
2426 // A partially constructed cache should never be seen by a racing
2427 // thread. We also use release_store() to save a new jmethodID
2428 // in the cache so a partially constructed jmethodID should never be
2429 // seen either. Cache reads of existing jmethodIDs proceed without a
2430 // lock, but cache writes of a new jmethodID requires uniqueness and
2431 // creation of the cache itself requires no leaks so a lock is
2432 // acquired in those two cases.
2433 //
2434 // If the RedefineClasses() API has been used, then this cache grows
2435 // in the redefinition safepoint.
2436
2437 if (jmeths == nullptr) {
2438 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2439 jmeths = _methods_jmethod_ids;
2440 // Still null?
2441 if (jmeths == nullptr) {
2442 size_t size = idnum_allocated_count();
2443 assert(size > (size_t)idnum, "should already have space");
2444 jmeths = create_jmethod_id_cache(size);
2445 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2446
2447 // publish jmeths
2448 release_set_methods_jmethod_ids(jmeths);
2449 return new_id;
2450 }
2451 }
2452
2453 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2454 if (id == nullptr) {
2455 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2456 id = jmeths[idnum + 1];
2457 // Still null?
2458 if (id == nullptr) {
2459 return update_jmethod_id(jmeths, method, idnum);
2460 }
2461 }
2462 return id;
2463 }
2464
2465 void InstanceKlass::update_methods_jmethod_cache() {
2466 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2467 jmethodID* cache = _methods_jmethod_ids;
2468 if (cache != nullptr) {
2469 size_t size = idnum_allocated_count();
2470 size_t old_size = (size_t)cache[0];
2471 if (old_size < size + 1) {
2472 // Allocate a larger one and copy entries to the new one.
2473 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2474 jmethodID* new_cache = create_jmethod_id_cache(size);
2475
2476 for (int i = 1; i <= (int)old_size; i++) {
2477 new_cache[i] = cache[i];
2478 }
2479 _methods_jmethod_ids = new_cache;
2480 FREE_C_HEAP_ARRAY(jmethodID, cache);
2481 }
2482 }
2483 }
2484
2485 // Make a jmethodID for all methods in this class. This makes getting all method
2486 // ids much, much faster with classes with more than 8
2487 // methods, and has a *substantial* effect on performance with jvmti
2488 // code that loads all jmethodIDs for all classes.
2489 void InstanceKlass::make_methods_jmethod_ids() {
2490 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2491 jmethodID* jmeths = _methods_jmethod_ids;
2492 if (jmeths == nullptr) {
2493 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2494 release_set_methods_jmethod_ids(jmeths);
2495 }
2496
2497 int length = methods()->length();
2498 for (int index = 0; index < length; index++) {
2499 Method* m = methods()->at(index);
2500 int idnum = m->method_idnum();
2501 assert(!m->is_old(), "should not have old methods or I'm confused");
2502 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2503 if (!m->is_overpass() && // skip overpasses
2504 id == nullptr) {
2505 id = Method::make_jmethod_id(class_loader_data(), m);
2506 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2507 }
2508 }
2509 }
2510
2511 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2512 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2513 int idnum = method->method_idnum();
2514 jmethodID* jmeths = methods_jmethod_ids_acquire();
2515 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2516 }
2517
2518 inline DependencyContext InstanceKlass::dependencies() {
2519 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2520 return dep_context;
2521 }
2522
2523 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2524 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2525 }
2526
2527 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2528 assert_lock_strong(CodeCache_lock);
2529 dependencies().add_dependent_nmethod(nm);
2530 }
2531
2532 void InstanceKlass::clean_dependency_context() {
2533 dependencies().clean_unloading_dependents();
2534 }
2535
2536 #ifndef PRODUCT
2537 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2538 dependencies().print_dependent_nmethods(verbose);
2539 }
2540
2541 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2542 return dependencies().is_dependent_nmethod(nm);
2543 }
2544 #endif //PRODUCT
2545
2546 void InstanceKlass::clean_weak_instanceklass_links() {
2547 clean_implementors_list();
2548 clean_method_data();
2549 }
2550
2551 void InstanceKlass::clean_implementors_list() {
2552 assert(is_loader_alive(), "this klass should be live");
2553 if (is_interface()) {
2554 assert (ClassUnloading, "only called for ClassUnloading");
2555 for (;;) {
2556 // Use load_acquire due to competing with inserts
2557 InstanceKlass* volatile* iklass = adr_implementor();
2558 assert(iklass != nullptr, "Klass must not be null");
2559 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2560 if (impl != nullptr && !impl->is_loader_alive()) {
2561 // null this field, might be an unloaded instance klass or null
2562 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2563 // Successfully unlinking implementor.
2564 if (log_is_enabled(Trace, class, unload)) {
2565 ResourceMark rm;
2566 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2567 }
2568 return;
2569 }
2570 } else {
2571 return;
2572 }
2573 }
2574 }
2575 }
2576
2577 void InstanceKlass::clean_method_data() {
2578 for (int m = 0; m < methods()->length(); m++) {
2579 MethodData* mdo = methods()->at(m)->method_data();
2580 if (mdo != nullptr) {
2581 mdo->clean_method_data(/*always_clean*/false);
2582 }
2583 }
2584 }
2585
2586 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2587 Klass::metaspace_pointers_do(it);
2588
2589 if (log_is_enabled(Trace, aot)) {
2590 ResourceMark rm;
2591 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2592 }
2593
2594 it->push(&_annotations);
2595 it->push((Klass**)&_array_klasses);
2596 if (!is_rewritten()) {
2597 it->push(&_constants, MetaspaceClosure::_writable);
2598 } else {
2599 it->push(&_constants);
2600 }
2601 it->push(&_inner_classes);
2602 #if INCLUDE_JVMTI
2603 it->push(&_previous_versions);
2604 #endif
2605 #if INCLUDE_CDS
2606 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2607 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2608 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2609 // The length check on the _methods is necessary because classes which don't have any
2610 // methods share the Universe::_the_empty_method_array which is in the RO region.
2611 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2612 // To handle jsr bytecode, new Method* maybe stored into _methods
2613 it->push(&_methods, MetaspaceClosure::_writable);
2614 } else {
2615 #endif
2616 it->push(&_methods);
2617 #if INCLUDE_CDS
2618 }
2619 #endif
2620 it->push(&_default_methods);
2621 it->push(&_local_interfaces);
2622 it->push(&_transitive_interfaces);
2623 it->push(&_method_ordering);
2624 if (!is_rewritten()) {
2625 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2626 } else {
2627 it->push(&_default_vtable_indices);
2628 }
2629
2630 it->push(&_fieldinfo_stream);
2631 it->push(&_fieldinfo_search_table);
2632 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2633 it->push(&_fields_status, MetaspaceClosure::_writable);
2634
2635 if (itable_length() > 0) {
2636 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2637 int method_table_offset_in_words = ioe->offset()/wordSize;
2638 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2639
2640 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2641 / itableOffsetEntry::size();
2642
2643 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2644 if (ioe->interface_klass() != nullptr) {
2645 it->push(ioe->interface_klass_addr());
2646 itableMethodEntry* ime = ioe->first_method_entry(this);
2647 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2648 for (int index = 0; index < n; index ++) {
2649 it->push(ime[index].method_addr());
2650 }
2651 }
2652 }
2653 }
2654
2655 it->push(&_nest_host);
2656 it->push(&_nest_members);
2657 it->push(&_permitted_subclasses);
2658 it->push(&_record_components);
2659 }
2660
2661 #if INCLUDE_CDS
2662 void InstanceKlass::remove_unshareable_info() {
2663
2664 if (is_linked()) {
2665 assert(can_be_verified_at_dumptime(), "must be");
2666 // Remember this so we can avoid walking the hierarchy at runtime.
2667 set_verified_at_dump_time();
2668 }
2669
2670 _misc_flags.set_has_init_deps_processed(false);
2671
2672 Klass::remove_unshareable_info();
2673
2674 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2675 // Classes are attempted to link during dumping and may fail,
2676 // but these classes are still in the dictionary and class list in CLD.
2677 // If the class has failed verification, there is nothing else to remove.
2678 return;
2679 }
2680
2681 // Reset to the 'allocated' state to prevent any premature accessing to
2682 // a shared class at runtime while the class is still being loaded and
2683 // restored. A class' init_state is set to 'loaded' at runtime when it's
2684 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2685 _init_state = allocated;
2686
2687 { // Otherwise this needs to take out the Compile_lock.
2688 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2689 init_implementor();
2690 }
2691
2692 // Call remove_unshareable_info() on other objects that belong to this class, except
2693 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2694 // ArchiveBuilder::make_klasses_shareable(),
2695
2696 for (int i = 0; i < methods()->length(); i++) {
2697 Method* m = methods()->at(i);
2698 m->remove_unshareable_info();
2699 }
2700
2701 // do array classes also.
2702 if (array_klasses() != nullptr) {
2703 array_klasses()->remove_unshareable_info();
2704 }
2705
2706 // These are not allocated from metaspace. They are safe to set to null.
2707 _source_debug_extension = nullptr;
2708 _dep_context = nullptr;
2709 _osr_nmethods_head = nullptr;
2710 #if INCLUDE_JVMTI
2711 _breakpoints = nullptr;
2712 _previous_versions = nullptr;
2713 _cached_class_file = nullptr;
2714 _jvmti_cached_class_field_map = nullptr;
2715 #endif
2716
2717 _init_thread = nullptr;
2718 _methods_jmethod_ids = nullptr;
2719 _jni_ids = nullptr;
2720 _oop_map_cache = nullptr;
2721 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2722 // keep _nest_host
2723 } else {
2724 // clear _nest_host to ensure re-load at runtime
2725 _nest_host = nullptr;
2726 }
2727 init_shared_package_entry();
2728 _dep_context_last_cleaned = 0;
2729 DEBUG_ONLY(_shared_class_load_count = 0);
2730
2731 remove_unshareable_flags();
2732
2733 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2734 }
2735
2736 void InstanceKlass::remove_unshareable_flags() {
2737 // clear all the flags/stats that shouldn't be in the archived version
2738 assert(!is_scratch_class(), "must be");
2739 assert(!has_been_redefined(), "must be");
2740 #if INCLUDE_JVMTI
2741 set_is_being_redefined(false);
2742 #endif
2743 set_has_resolved_methods(false);
2744 }
2745
2746 void InstanceKlass::remove_java_mirror() {
2747 Klass::remove_java_mirror();
2748
2749 // do array classes also.
2750 if (array_klasses() != nullptr) {
2751 array_klasses()->remove_java_mirror();
2752 }
2753 }
2754
2755 void InstanceKlass::init_shared_package_entry() {
2756 assert(CDSConfig::is_dumping_archive(), "must be");
2757 #if !INCLUDE_CDS_JAVA_HEAP
2758 _package_entry = nullptr;
2759 #else
2760 if (CDSConfig::is_dumping_full_module_graph()) {
2761 if (defined_by_other_loaders()) {
2762 _package_entry = nullptr;
2763 } else {
2764 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2765 }
2766 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2767 CDSConfig::is_using_full_module_graph() &&
2768 AOTMetaspace::in_aot_cache(_package_entry)) {
2769 // _package_entry is an archived package in the base archive. Leave it as is.
2770 } else {
2771 _package_entry = nullptr;
2772 }
2773 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2774 #endif
2775 }
2776
2777 void InstanceKlass::compute_has_loops_flag_for_methods() {
2778 Array<Method*>* methods = this->methods();
2779 for (int index = 0; index < methods->length(); ++index) {
2780 Method* m = methods->at(index);
2781 if (!m->is_overpass()) { // work around JDK-8305771
2782 m->compute_has_loops_flag();
2783 }
2784 }
2785 }
2786
2787 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2788 PackageEntry* pkg_entry, TRAPS) {
2789 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2790 // before the InstanceKlass is added to the SystemDictionary. Make
2791 // sure the current state is <loaded.
2792 assert(!is_loaded(), "invalid init state");
2793 assert(!shared_loading_failed(), "Must not try to load failed class again");
2794 set_package(loader_data, pkg_entry, CHECK);
2795 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2796
2797 Array<Method*>* methods = this->methods();
2798 int num_methods = methods->length();
2799 for (int index = 0; index < num_methods; ++index) {
2800 methods->at(index)->restore_unshareable_info(CHECK);
2801 }
2802 #if INCLUDE_JVMTI
2803 if (JvmtiExport::has_redefined_a_class()) {
2804 // Reinitialize vtable because RedefineClasses may have changed some
2805 // entries in this vtable for super classes so the CDS vtable might
2806 // point to old or obsolete entries. RedefineClasses doesn't fix up
2807 // vtables in the shared system dictionary, only the main one.
2808 // It also redefines the itable too so fix that too.
2809 // First fix any default methods that point to a super class that may
2810 // have been redefined.
2811 bool trace_name_printed = false;
2812 adjust_default_methods(&trace_name_printed);
2813 if (verified_at_dump_time()) {
2814 // Initialize vtable and itable for classes which can be verified at dump time.
2815 // Unlinked classes such as old classes with major version < 50 cannot be verified
2816 // at dump time.
2817 vtable().initialize_vtable();
2818 itable().initialize_itable();
2819 }
2820 }
2821 #endif // INCLUDE_JVMTI
2822
2823 // restore constant pool resolved references
2824 constants()->restore_unshareable_info(CHECK);
2825
2826 if (array_klasses() != nullptr) {
2827 // To get a consistent list of classes we need MultiArray_lock to ensure
2828 // array classes aren't observed while they are being restored.
2829 RecursiveLocker rl(MultiArray_lock, THREAD);
2830 assert(this == array_klasses()->bottom_klass(), "sanity");
2831 // Array classes have null protection domain.
2832 // --> see ArrayKlass::complete_create_array_klass()
2833 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2834 }
2835
2836 // Initialize @ValueBased class annotation if not already set in the archived klass.
2837 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2838 set_is_value_based();
2839 }
2840
2841 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2842 }
2843
2844 bool InstanceKlass::can_be_verified_at_dumptime() const {
2845 if (AOTMetaspace::in_aot_cache(this)) {
2846 // This is a class that was dumped into the base archive, so we know
2847 // it was verified at dump time.
2848 return true;
2849 }
2850
2851 if (CDSConfig::is_preserving_verification_constraints()) {
2852 return true;
2853 }
2854
2855 if (CDSConfig::is_old_class_for_verifier(this)) {
2856 // The old verifier does not save verification constraints, so at run time
2857 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
2858 return false;
2859 }
2860 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
2861 return false;
2862 }
2863 Array<InstanceKlass*>* interfaces = local_interfaces();
2864 int len = interfaces->length();
2865 for (int i = 0; i < len; i++) {
2866 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2867 return false;
2868 }
2869 }
2870 return true;
2871 }
2872
2873 #endif // INCLUDE_CDS
2874
2875 #if INCLUDE_JVMTI
2876 static void clear_all_breakpoints(Method* m) {
2877 m->clear_all_breakpoints();
2878 }
2879 #endif
2880
2881 void InstanceKlass::unload_class(InstanceKlass* ik) {
2882
2883 if (ik->is_scratch_class()) {
2884 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2885 return;
2886 }
2887 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2888
2889 // Release dependencies.
2890 ik->dependencies().remove_all_dependents();
2891
2892 // notify the debugger
2893 if (JvmtiExport::should_post_class_unload()) {
2894 JvmtiExport::post_class_unload(ik);
2895 }
2896
2897 // notify ClassLoadingService of class unload
2898 ClassLoadingService::notify_class_unloaded(ik);
2899
2900 SystemDictionaryShared::handle_class_unloading(ik);
2901
2902 if (log_is_enabled(Info, class, unload)) {
2903 ResourceMark rm;
2904 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2905 }
2906
2907 Events::log_class_unloading(Thread::current(), ik);
2908
2909 #if INCLUDE_JFR
2910 assert(ik != nullptr, "invariant");
2911 EventClassUnload event;
2912 event.set_unloadedClass(ik);
2913 event.set_definingClassLoader(ik->class_loader_data());
2914 event.commit();
2915 #endif
2916 }
2917
2918 static void method_release_C_heap_structures(Method* m) {
2919 m->release_C_heap_structures();
2920 }
2921
2922 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2923 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2924 // Clean up C heap
2925 Klass::release_C_heap_structures();
2926
2927 // Deallocate and call destructors for MDO mutexes
2928 if (release_sub_metadata) {
2929 methods_do(method_release_C_heap_structures);
2930 }
2931
2932 // Deallocate oop map cache
2933 if (_oop_map_cache != nullptr) {
2934 delete _oop_map_cache;
2935 _oop_map_cache = nullptr;
2936 }
2937
2938 // Deallocate JNI identifiers for jfieldIDs
2939 JNIid::deallocate(jni_ids());
2940 set_jni_ids(nullptr);
2941
2942 jmethodID* jmeths = _methods_jmethod_ids;
2943 if (jmeths != nullptr) {
2944 release_set_methods_jmethod_ids(nullptr);
2945 FreeHeap(jmeths);
2946 }
2947
2948 assert(_dep_context == nullptr,
2949 "dependencies should already be cleaned");
2950
2951 #if INCLUDE_JVMTI
2952 // Deallocate breakpoint records
2953 if (breakpoints() != nullptr) {
2954 methods_do(clear_all_breakpoints);
2955 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2956 }
2957
2958 // deallocate the cached class file
2959 if (_cached_class_file != nullptr) {
2960 os::free(_cached_class_file);
2961 _cached_class_file = nullptr;
2962 }
2963 #endif
2964
2965 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2966
2967 if (release_sub_metadata) {
2968 constants()->release_C_heap_structures();
2969 }
2970 }
2971
2972 // The constant pool is on stack if any of the methods are executing or
2973 // referenced by handles.
2974 bool InstanceKlass::on_stack() const {
2975 return _constants->on_stack();
2976 }
2977
2978 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
2979 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
2980 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
2981
2982 // minor and major version numbers of class file
2983 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
2984 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
2985 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
2986 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
2987
2988 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
2989 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
2990 if (ik->constants()->version() == version) {
2991 return ik;
2992 }
2993 }
2994 return nullptr;
2995 }
2996
2997 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2998 if (array == nullptr) {
2999 _source_debug_extension = nullptr;
3000 } else {
3001 // Adding one to the attribute length in order to store a null terminator
3002 // character could cause an overflow because the attribute length is
3003 // already coded with an u4 in the classfile, but in practice, it's
3004 // unlikely to happen.
3005 assert((length+1) > length, "Overflow checking");
3006 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3007 for (int i = 0; i < length; i++) {
3008 sde[i] = array[i];
3009 }
3010 sde[length] = '\0';
3011 _source_debug_extension = sde;
3012 }
3013 }
3014
3015 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3016 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3017 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3018
3019 const char* InstanceKlass::signature_name() const {
3020
3021 // Get the internal name as a c string
3022 const char* src = (const char*) (name()->as_C_string());
3023 const int src_length = (int)strlen(src);
3024
3025 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3026
3027 // Add L as type indicator
3028 int dest_index = 0;
3029 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3030
3031 // Add the actual class name
3032 for (int src_index = 0; src_index < src_length; ) {
3033 dest[dest_index++] = src[src_index++];
3034 }
3035
3036 if (is_hidden()) { // Replace the last '+' with a '.'.
3037 for (int index = (int)src_length; index > 0; index--) {
3038 if (dest[index] == '+') {
3039 dest[index] = JVM_SIGNATURE_DOT;
3040 break;
3041 }
3042 }
3043 }
3044
3045 // Add the semicolon and the null
3046 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3047 dest[dest_index] = '\0';
3048 return dest;
3049 }
3050
3051 ModuleEntry* InstanceKlass::module() const {
3052 if (is_hidden() &&
3053 in_unnamed_package() &&
3054 class_loader_data()->has_class_mirror_holder()) {
3055 // For a non-strong hidden class defined to an unnamed package,
3056 // its (class held) CLD will not have an unnamed module created for it.
3057 // Two choices to find the correct ModuleEntry:
3058 // 1. If hidden class is within a nest, use nest host's module
3059 // 2. Find the unnamed module off from the class loader
3060 // For now option #2 is used since a nest host is not set until
3061 // after the instance class is created in jvm_lookup_define_class().
3062 if (class_loader_data()->is_boot_class_loader_data()) {
3063 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3064 } else {
3065 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3066 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3067 return java_lang_Module::module_entry(module);
3068 }
3069 }
3070
3071 // Class is in a named package
3072 if (!in_unnamed_package()) {
3073 return _package_entry->module();
3074 }
3075
3076 // Class is in an unnamed package, return its loader's unnamed module
3077 return class_loader_data()->unnamed_module();
3078 }
3079
3080 bool InstanceKlass::in_javabase_module() const {
3081 return module()->name() == vmSymbols::java_base();
3082 }
3083
3084 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3085
3086 // ensure java/ packages only loaded by boot or platform builtin loaders
3087 // not needed for shared class since CDS does not archive prohibited classes.
3088 if (!in_aot_cache()) {
3089 check_prohibited_package(name(), loader_data, CHECK);
3090 }
3091
3092 if (in_aot_cache() && _package_entry != nullptr) {
3093 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3094 // we can use the saved package
3095 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3096 return;
3097 } else {
3098 _package_entry = nullptr;
3099 }
3100 }
3101
3102 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3103 // it returns, so we need to decrement it when the current function exits.
3104 TempNewSymbol from_class_name =
3105 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3106
3107 Symbol* pkg_name;
3108 if (pkg_entry != nullptr) {
3109 pkg_name = pkg_entry->name();
3110 } else {
3111 pkg_name = from_class_name;
3112 }
3113
3114 if (pkg_name != nullptr && loader_data != nullptr) {
3115
3116 // Find in class loader's package entry table.
3117 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3118
3119 // If the package name is not found in the loader's package
3120 // entry table, it is an indication that the package has not
3121 // been defined. Consider it defined within the unnamed module.
3122 if (_package_entry == nullptr) {
3123
3124 if (!ModuleEntryTable::javabase_defined()) {
3125 // Before java.base is defined during bootstrapping, define all packages in
3126 // the java.base module. If a non-java.base package is erroneously placed
3127 // in the java.base module it will be caught later when java.base
3128 // is defined by ModuleEntryTable::verify_javabase_packages check.
3129 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3130 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3131 } else {
3132 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3133 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3134 }
3135
3136 // A package should have been successfully created
3137 DEBUG_ONLY(ResourceMark rm(THREAD));
3138 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3139 name()->as_C_string(), loader_data->loader_name_and_id());
3140 }
3141
3142 if (log_is_enabled(Debug, module)) {
3143 ResourceMark rm(THREAD);
3144 ModuleEntry* m = _package_entry->module();
3145 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3146 external_name(),
3147 pkg_name->as_C_string(),
3148 loader_data->loader_name_and_id(),
3149 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3150 }
3151 } else {
3152 ResourceMark rm(THREAD);
3153 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3154 external_name(),
3155 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3156 UNNAMED_MODULE);
3157 }
3158 }
3159
3160 // Function set_classpath_index ensures that for a non-null _package_entry
3161 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3162 // It then sets the classpath_index in the package entry record.
3163 //
3164 // The classpath_index field is used to find the entry on the boot loader class
3165 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3166 // in an unnamed module. It is also used to indicate (for all packages whose
3167 // classes are loaded by the boot loader) that at least one of the package's
3168 // classes has been loaded.
3169 void InstanceKlass::set_classpath_index(s2 path_index) {
3170 if (_package_entry != nullptr) {
3171 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3172 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3173 assert(path_index != -1, "Unexpected classpath_index");
3174 _package_entry->set_classpath_index(path_index);
3175 }
3176 }
3177
3178 // different versions of is_same_class_package
3179
3180 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3181 oop classloader1 = this->class_loader();
3182 PackageEntry* classpkg1 = this->package();
3183 if (class2->is_objArray_klass()) {
3184 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3185 }
3186
3187 oop classloader2;
3188 PackageEntry* classpkg2;
3189 if (class2->is_instance_klass()) {
3190 classloader2 = class2->class_loader();
3191 classpkg2 = class2->package();
3192 } else {
3193 assert(class2->is_typeArray_klass(), "should be type array");
3194 classloader2 = nullptr;
3195 classpkg2 = nullptr;
3196 }
3197
3198 // Same package is determined by comparing class loader
3199 // and package entries. Both must be the same. This rule
3200 // applies even to classes that are defined in the unnamed
3201 // package, they still must have the same class loader.
3202 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3203 return true;
3204 }
3205
3206 return false;
3207 }
3208
3209 // return true if this class and other_class are in the same package. Classloader
3210 // and classname information is enough to determine a class's package
3211 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3212 const Symbol* other_class_name) const {
3213 if (class_loader() != other_class_loader) {
3214 return false;
3215 }
3216 if (name()->fast_compare(other_class_name) == 0) {
3217 return true;
3218 }
3219
3220 {
3221 ResourceMark rm;
3222
3223 bool bad_class_name = false;
3224 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3225 if (bad_class_name) {
3226 return false;
3227 }
3228 // Check that package_from_class_name() returns null, not "", if there is no package.
3229 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3230
3231 const Symbol* const this_package_name =
3232 this->package() != nullptr ? this->package()->name() : nullptr;
3233
3234 if (this_package_name == nullptr || other_pkg == nullptr) {
3235 // One of the two doesn't have a package. Only return true if the other
3236 // one also doesn't have a package.
3237 return this_package_name == other_pkg;
3238 }
3239
3240 // Check if package is identical
3241 return this_package_name->fast_compare(other_pkg) == 0;
3242 }
3243 }
3244
3245 static bool is_prohibited_package_slow(Symbol* class_name) {
3246 // Caller has ResourceMark
3247 int length;
3248 jchar* unicode = class_name->as_unicode(length);
3249 return (length >= 5 &&
3250 unicode[0] == 'j' &&
3251 unicode[1] == 'a' &&
3252 unicode[2] == 'v' &&
3253 unicode[3] == 'a' &&
3254 unicode[4] == '/');
3255 }
3256
3257 // Only boot and platform class loaders can define classes in "java/" packages.
3258 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3259 ClassLoaderData* loader_data,
3260 TRAPS) {
3261 if (!loader_data->is_boot_class_loader_data() &&
3262 !loader_data->is_platform_class_loader_data() &&
3263 class_name != nullptr && class_name->utf8_length() >= 5) {
3264 ResourceMark rm(THREAD);
3265 bool prohibited;
3266 const u1* base = class_name->base();
3267 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3268 prohibited = is_prohibited_package_slow(class_name);
3269 } else {
3270 char* name = class_name->as_C_string();
3271 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3272 }
3273 if (prohibited) {
3274 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3275 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3276 char* name = pkg_name->as_C_string();
3277 const char* class_loader_name = loader_data->loader_name_and_id();
3278 StringUtils::replace_no_expand(name, "/", ".");
3279 const char* msg_text1 = "Class loader (instance of): ";
3280 const char* msg_text2 = " tried to load prohibited package name: ";
3281 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3282 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3283 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3284 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3285 }
3286 }
3287 return;
3288 }
3289
3290 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3291 constantPoolHandle i_cp(THREAD, constants());
3292 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3293 int ioff = iter.inner_class_info_index();
3294 if (ioff != 0) {
3295 // Check to see if the name matches the class we're looking for
3296 // before attempting to find the class.
3297 if (i_cp->klass_name_at_matches(this, ioff)) {
3298 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3299 if (this == inner_klass) {
3300 *ooff = iter.outer_class_info_index();
3301 *noff = iter.inner_name_index();
3302 return true;
3303 }
3304 }
3305 }
3306 }
3307 return false;
3308 }
3309
3310 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3311 InstanceKlass* outer_klass = nullptr;
3312 *inner_is_member = false;
3313 int ooff = 0, noff = 0;
3314 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3315 if (has_inner_classes_attr) {
3316 constantPoolHandle i_cp(THREAD, constants());
3317 if (ooff != 0) {
3318 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3319 if (!ok->is_instance_klass()) {
3320 // If the outer class is not an instance klass then it cannot have
3321 // declared any inner classes.
3322 ResourceMark rm(THREAD);
3323 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3324 Exceptions::fthrow(
3325 THREAD_AND_LOCATION,
3326 vmSymbols::java_lang_IncompatibleClassChangeError(),
3327 "%s and %s disagree on InnerClasses attribute",
3328 ok->external_name(),
3329 external_name());
3330 return nullptr;
3331 }
3332 outer_klass = InstanceKlass::cast(ok);
3333 *inner_is_member = true;
3334 }
3335 if (nullptr == outer_klass) {
3336 // It may be a local class; try for that.
3337 int encl_method_class_idx = enclosing_method_class_index();
3338 if (encl_method_class_idx != 0) {
3339 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3340 outer_klass = InstanceKlass::cast(ok);
3341 *inner_is_member = false;
3342 }
3343 }
3344 }
3345
3346 // If no inner class attribute found for this class.
3347 if (nullptr == outer_klass) return nullptr;
3348
3349 // Throws an exception if outer klass has not declared k as an inner klass
3350 // We need evidence that each klass knows about the other, or else
3351 // the system could allow a spoof of an inner class to gain access rights.
3352 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3353 return outer_klass;
3354 }
3355
3356 u2 InstanceKlass::compute_modifier_flags() const {
3357 u2 access = access_flags().as_unsigned_short();
3358
3359 // But check if it happens to be member class.
3360 InnerClassesIterator iter(this);
3361 for (; !iter.done(); iter.next()) {
3362 int ioff = iter.inner_class_info_index();
3363 // Inner class attribute can be zero, skip it.
3364 // Strange but true: JVM spec. allows null inner class refs.
3365 if (ioff == 0) continue;
3366
3367 // only look at classes that are already loaded
3368 // since we are looking for the flags for our self.
3369 Symbol* inner_name = constants()->klass_name_at(ioff);
3370 if (name() == inner_name) {
3371 // This is really a member class.
3372 access = iter.inner_access_flags();
3373 break;
3374 }
3375 }
3376 // Remember to strip ACC_SUPER bit
3377 return (access & (~JVM_ACC_SUPER));
3378 }
3379
3380 jint InstanceKlass::jvmti_class_status() const {
3381 jint result = 0;
3382
3383 if (is_linked()) {
3384 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3385 }
3386
3387 if (is_initialized()) {
3388 assert(is_linked(), "Class status is not consistent");
3389 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3390 }
3391 if (is_in_error_state()) {
3392 result |= JVMTI_CLASS_STATUS_ERROR;
3393 }
3394 return result;
3395 }
3396
3397 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3398 bool implements_interface; // initialized by method_at_itable_or_null
3399 Method* m = method_at_itable_or_null(holder, index,
3400 implements_interface); // out parameter
3401 if (m != nullptr) {
3402 assert(implements_interface, "sanity");
3403 return m;
3404 } else if (implements_interface) {
3405 // Throw AbstractMethodError since corresponding itable slot is empty.
3406 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3407 } else {
3408 // If the interface isn't implemented by the receiver class,
3409 // the VM should throw IncompatibleClassChangeError.
3410 ResourceMark rm(THREAD);
3411 stringStream ss;
3412 bool same_module = (module() == holder->module());
3413 ss.print("Receiver class %s does not implement "
3414 "the interface %s defining the method to be called "
3415 "(%s%s%s)",
3416 external_name(), holder->external_name(),
3417 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3418 (same_module) ? "" : "; ",
3419 (same_module) ? "" : holder->class_in_module_of_loader());
3420 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3421 }
3422 }
3423
3424 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3425 klassItable itable(this);
3426 for (int i = 0; i < itable.size_offset_table(); i++) {
3427 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3428 if (offset_entry->interface_klass() == holder) {
3429 implements_interface = true;
3430 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3431 Method* m = ime[index].method();
3432 return m;
3433 }
3434 }
3435 implements_interface = false;
3436 return nullptr; // offset entry not found
3437 }
3438
3439 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3440 assert(is_linked(), "required");
3441 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3442 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3443
3444 int vtable_index = Method::invalid_vtable_index;
3445 Symbol* name = intf_method->name();
3446 Symbol* signature = intf_method->signature();
3447
3448 // First check in default method array
3449 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3450 int index = find_method_index(default_methods(),
3451 name, signature,
3452 Klass::OverpassLookupMode::find,
3453 Klass::StaticLookupMode::find,
3454 Klass::PrivateLookupMode::find);
3455 if (index >= 0) {
3456 vtable_index = default_vtable_indices()->at(index);
3457 }
3458 }
3459 if (vtable_index == Method::invalid_vtable_index) {
3460 // get vtable_index for miranda methods
3461 klassVtable vt = vtable();
3462 vtable_index = vt.index_of_miranda(name, signature);
3463 }
3464 return vtable_index;
3465 }
3466
3467 #if INCLUDE_JVMTI
3468 // update default_methods for redefineclasses for methods that are
3469 // not yet in the vtable due to concurrent subclass define and superinterface
3470 // redefinition
3471 // Note: those in the vtable, should have been updated via adjust_method_entries
3472 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3473 // search the default_methods for uses of either obsolete or EMCP methods
3474 if (default_methods() != nullptr) {
3475 for (int index = 0; index < default_methods()->length(); index ++) {
3476 Method* old_method = default_methods()->at(index);
3477 if (old_method == nullptr || !old_method->is_old()) {
3478 continue; // skip uninteresting entries
3479 }
3480 assert(!old_method->is_deleted(), "default methods may not be deleted");
3481 Method* new_method = old_method->get_new_method();
3482 default_methods()->at_put(index, new_method);
3483
3484 if (log_is_enabled(Info, redefine, class, update)) {
3485 ResourceMark rm;
3486 if (!(*trace_name_printed)) {
3487 log_info(redefine, class, update)
3488 ("adjust: klassname=%s default methods from name=%s",
3489 external_name(), old_method->method_holder()->external_name());
3490 *trace_name_printed = true;
3491 }
3492 log_debug(redefine, class, update, vtables)
3493 ("default method update: %s(%s) ",
3494 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3495 }
3496 }
3497 }
3498 }
3499 #endif // INCLUDE_JVMTI
3500
3501 // On-stack replacement stuff
3502 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3503 assert_lock_strong(NMethodState_lock);
3504 #ifndef PRODUCT
3505 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3506 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3507 "redundant OSR recompilation detected. memory leak in CodeCache!");
3508 #endif
3509 // only one compilation can be active
3510 assert(n->is_osr_method(), "wrong kind of nmethod");
3511 n->set_osr_link(osr_nmethods_head());
3512 set_osr_nmethods_head(n);
3513 // Raise the highest osr level if necessary
3514 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3515
3516 // Get rid of the osr methods for the same bci that have lower levels.
3517 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3518 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3519 if (inv != nullptr && inv->is_in_use()) {
3520 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3521 }
3522 }
3523 }
3524
3525 // Remove osr nmethod from the list. Return true if found and removed.
3526 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3527 // This is a short non-blocking critical region, so the no safepoint check is ok.
3528 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3529 assert(n->is_osr_method(), "wrong kind of nmethod");
3530 nmethod* last = nullptr;
3531 nmethod* cur = osr_nmethods_head();
3532 int max_level = CompLevel_none; // Find the max comp level excluding n
3533 Method* m = n->method();
3534 // Search for match
3535 bool found = false;
3536 while(cur != nullptr && cur != n) {
3537 if (m == cur->method()) {
3538 // Find max level before n
3539 max_level = MAX2(max_level, cur->comp_level());
3540 }
3541 last = cur;
3542 cur = cur->osr_link();
3543 }
3544 nmethod* next = nullptr;
3545 if (cur == n) {
3546 found = true;
3547 next = cur->osr_link();
3548 if (last == nullptr) {
3549 // Remove first element
3550 set_osr_nmethods_head(next);
3551 } else {
3552 last->set_osr_link(next);
3553 }
3554 }
3555 n->set_osr_link(nullptr);
3556 cur = next;
3557 while (cur != nullptr) {
3558 // Find max level after n
3559 if (m == cur->method()) {
3560 max_level = MAX2(max_level, cur->comp_level());
3561 }
3562 cur = cur->osr_link();
3563 }
3564 m->set_highest_osr_comp_level(max_level);
3565 return found;
3566 }
3567
3568 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3569 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3570 nmethod* osr = osr_nmethods_head();
3571 int found = 0;
3572 while (osr != nullptr) {
3573 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3574 if (osr->method() == m) {
3575 deopt_scope->mark(osr);
3576 found++;
3577 }
3578 osr = osr->osr_link();
3579 }
3580 return found;
3581 }
3582
3583 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3584 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3585 nmethod* osr = osr_nmethods_head();
3586 nmethod* best = nullptr;
3587 while (osr != nullptr) {
3588 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3589 // There can be a time when a c1 osr method exists but we are waiting
3590 // for a c2 version. When c2 completes its osr nmethod we will trash
3591 // the c1 version and only be able to find the c2 version. However
3592 // while we overflow in the c1 code at back branches we don't want to
3593 // try and switch to the same code as we are already running
3594
3595 if (osr->method() == m &&
3596 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3597 if (match_level) {
3598 if (osr->comp_level() == comp_level) {
3599 // Found a match - return it.
3600 return osr;
3601 }
3602 } else {
3603 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3604 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3605 // Found the best possible - return it.
3606 return osr;
3607 }
3608 best = osr;
3609 }
3610 }
3611 }
3612 osr = osr->osr_link();
3613 }
3614
3615 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3616 if (best != nullptr && best->comp_level() >= comp_level) {
3617 return best;
3618 }
3619 return nullptr;
3620 }
3621
3622 // -----------------------------------------------------------------------------------------------------
3623 // Printing
3624
3625 #define BULLET " - "
3626
3627 static const char* state_names[] = {
3628 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3629 };
3630
3631 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3632 for (int i = 0; i < len; i++) {
3633 intptr_t e = start[i];
3634 st->print("%d : " INTPTR_FORMAT, i, e);
3635 if (MetaspaceObj::is_valid((Metadata*)e)) {
3636 st->print(" ");
3637 ((Metadata*)e)->print_value_on(st);
3638 }
3639 st->cr();
3640 }
3641 }
3642
3643 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3644 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3645 }
3646
3647 const char* InstanceKlass::init_state_name() const {
3648 return state_names[init_state()];
3649 }
3650
3651 void InstanceKlass::print_on(outputStream* st) const {
3652 assert(is_klass(), "must be klass");
3653 Klass::print_on(st);
3654
3655 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3656 st->print(BULLET"klass size: %d", size()); st->cr();
3657 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3658 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3659 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3660 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3661 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3662 st->print(BULLET"sub: ");
3663 Klass* sub = subklass();
3664 int n;
3665 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3666 if (n < MaxSubklassPrintSize) {
3667 sub->print_value_on(st);
3668 st->print(" ");
3669 }
3670 }
3671 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3672 st->cr();
3673
3674 if (is_interface()) {
3675 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3676 if (nof_implementors() == 1) {
3677 st->print_cr(BULLET"implementor: ");
3678 st->print(" ");
3679 implementor()->print_value_on(st);
3680 st->cr();
3681 }
3682 }
3683
3684 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3685 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3686 if (Verbose || WizardMode) {
3687 Array<Method*>* method_array = methods();
3688 for (int i = 0; i < method_array->length(); i++) {
3689 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3690 }
3691 }
3692 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3693 if (default_methods() != nullptr) {
3694 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3695 if (Verbose) {
3696 Array<Method*>* method_array = default_methods();
3697 for (int i = 0; i < method_array->length(); i++) {
3698 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3699 }
3700 }
3701 }
3702 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3703 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3704 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3705
3706 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3707
3708 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3709 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3710
3711 if (secondary_supers() != nullptr) {
3712 if (Verbose) {
3713 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3714 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3715 for (int i = 0; i < _secondary_supers->length(); i++) {
3716 ResourceMark rm; // for external_name()
3717 Klass* secondary_super = _secondary_supers->at(i);
3718 st->print(BULLET"%2d:", i);
3719 if (is_hashed) {
3720 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3721 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3722 st->print(" dist:%02d:", distance);
3723 }
3724 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3725 }
3726 }
3727 }
3728 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3729
3730 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3731 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3732 if (source_debug_extension() != nullptr) {
3733 st->print(BULLET"source debug extension: ");
3734 st->print("%s", source_debug_extension());
3735 st->cr();
3736 }
3737 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3738 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3739 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3740 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3741 {
3742 bool have_pv = false;
3743 // previous versions are linked together through the InstanceKlass
3744 for (InstanceKlass* pv_node = previous_versions();
3745 pv_node != nullptr;
3746 pv_node = pv_node->previous_versions()) {
3747 if (!have_pv)
3748 st->print(BULLET"previous version: ");
3749 have_pv = true;
3750 pv_node->constants()->print_value_on(st);
3751 }
3752 if (have_pv) st->cr();
3753 }
3754
3755 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3756 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3757 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3758 print_on_maybe_null(st, BULLET"record components: ", record_components());
3759 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3760 if (java_mirror() != nullptr) {
3761 st->print(BULLET"java mirror: ");
3762 java_mirror()->print_value_on(st);
3763 st->cr();
3764 } else {
3765 st->print_cr(BULLET"java mirror: null");
3766 }
3767 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3768 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3769 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3770 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3771 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3772
3773 FieldPrinter print_static_field(st);
3774 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3775 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3776 FieldPrinter print_nonstatic_field(st);
3777 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3778 ik->print_nonstatic_fields(&print_nonstatic_field);
3779
3780 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3781 OopMapBlock* map = start_of_nonstatic_oop_maps();
3782 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3783 while (map < end_map) {
3784 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3785 map++;
3786 }
3787 st->cr();
3788
3789 if (fieldinfo_search_table() != nullptr) {
3790 st->print_cr(BULLET"---- field info search table:");
3791 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
3792 }
3793 }
3794
3795 void InstanceKlass::print_value_on(outputStream* st) const {
3796 assert(is_klass(), "must be klass");
3797 if (Verbose || WizardMode) access_flags().print_on(st);
3798 name()->print_value_on(st);
3799 }
3800
3801 void FieldPrinter::do_field(fieldDescriptor* fd) {
3802 _st->print(BULLET);
3803 if (_obj == nullptr) {
3804 fd->print_on(_st);
3805 _st->cr();
3806 } else {
3807 fd->print_on_for(_st, _obj);
3808 _st->cr();
3809 }
3810 }
3811
3812
3813 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3814 Klass::oop_print_on(obj, st);
3815
3816 if (this == vmClasses::String_klass()) {
3817 typeArrayOop value = java_lang_String::value(obj);
3818 juint length = java_lang_String::length(obj);
3819 if (value != nullptr &&
3820 value->is_typeArray() &&
3821 length <= (juint) value->length()) {
3822 st->print(BULLET"string: ");
3823 java_lang_String::print(obj, st);
3824 st->cr();
3825 }
3826 }
3827
3828 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3829 FieldPrinter print_field(st, obj);
3830 print_nonstatic_fields(&print_field);
3831
3832 if (this == vmClasses::Class_klass()) {
3833 st->print(BULLET"signature: ");
3834 java_lang_Class::print_signature(obj, st);
3835 st->cr();
3836 Klass* real_klass = java_lang_Class::as_Klass(obj);
3837 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3838 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3839 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3840 }
3841 } else if (this == vmClasses::MethodType_klass()) {
3842 st->print(BULLET"signature: ");
3843 java_lang_invoke_MethodType::print_signature(obj, st);
3844 st->cr();
3845 }
3846 }
3847
3848 #ifndef PRODUCT
3849
3850 bool InstanceKlass::verify_itable_index(int i) {
3851 int method_count = klassItable::method_count_for_interface(this);
3852 assert(i >= 0 && i < method_count, "index out of bounds");
3853 return true;
3854 }
3855
3856 #endif //PRODUCT
3857
3858 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3859 st->print("a ");
3860 name()->print_value_on(st);
3861 obj->print_address_on(st);
3862 if (this == vmClasses::String_klass()
3863 && java_lang_String::value(obj) != nullptr) {
3864 ResourceMark rm;
3865 int len = java_lang_String::length(obj);
3866 int plen = (len < 24 ? len : 12);
3867 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3868 st->print(" = \"%s\"", str);
3869 if (len > plen)
3870 st->print("...[%d]", len);
3871 } else if (this == vmClasses::Class_klass()) {
3872 Klass* k = java_lang_Class::as_Klass(obj);
3873 st->print(" = ");
3874 if (k != nullptr) {
3875 k->print_value_on(st);
3876 } else {
3877 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3878 st->print("%s", tname ? tname : "type?");
3879 }
3880 } else if (this == vmClasses::MethodType_klass()) {
3881 st->print(" = ");
3882 java_lang_invoke_MethodType::print_signature(obj, st);
3883 } else if (java_lang_boxing_object::is_instance(obj)) {
3884 st->print(" = ");
3885 java_lang_boxing_object::print(obj, st);
3886 } else if (this == vmClasses::LambdaForm_klass()) {
3887 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3888 if (vmentry != nullptr) {
3889 st->print(" => ");
3890 vmentry->print_value_on(st);
3891 }
3892 } else if (this == vmClasses::MemberName_klass()) {
3893 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3894 if (vmtarget != nullptr) {
3895 st->print(" = ");
3896 vmtarget->print_value_on(st);
3897 } else {
3898 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3899 oop name = java_lang_invoke_MemberName::name(obj);
3900 if (clazz != nullptr) {
3901 clazz->print_value_on(st);
3902 } else {
3903 st->print("null");
3904 }
3905 st->print(".");
3906 if (name != nullptr) {
3907 name->print_value_on(st);
3908 } else {
3909 st->print("null");
3910 }
3911 }
3912 }
3913 }
3914
3915 const char* InstanceKlass::internal_name() const {
3916 return external_name();
3917 }
3918
3919 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3920 const ModuleEntry* module_entry,
3921 const ClassFileStream* cfs) const {
3922
3923 if (ClassListWriter::is_enabled()) {
3924 ClassListWriter::write(this, cfs);
3925 }
3926
3927 print_class_load_helper(loader_data, module_entry, cfs);
3928 print_class_load_cause_logging();
3929 }
3930
3931 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3932 const ModuleEntry* module_entry,
3933 const ClassFileStream* cfs) const {
3934
3935 if (!log_is_enabled(Info, class, load)) {
3936 return;
3937 }
3938
3939 ResourceMark rm;
3940 LogMessage(class, load) msg;
3941 stringStream info_stream;
3942
3943 // Name and class hierarchy info
3944 info_stream.print("%s", external_name());
3945
3946 // Source
3947 if (cfs != nullptr) {
3948 if (cfs->source() != nullptr) {
3949 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3950 if (module_name != nullptr) {
3951 // When the boot loader created the stream, it didn't know the module name
3952 // yet. Let's format it now.
3953 if (cfs->from_boot_loader_modules_image()) {
3954 info_stream.print(" source: jrt:/%s", module_name);
3955 } else {
3956 info_stream.print(" source: %s", cfs->source());
3957 }
3958 } else {
3959 info_stream.print(" source: %s", cfs->source());
3960 }
3961 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3962 Thread* current = Thread::current();
3963 Klass* caller = current->is_Java_thread() ?
3964 JavaThread::cast(current)->security_get_caller_class(1):
3965 nullptr;
3966 // caller can be null, for example, during a JVMTI VM_Init hook
3967 if (caller != nullptr) {
3968 info_stream.print(" source: instance of %s", caller->external_name());
3969 } else {
3970 // source is unknown
3971 }
3972 } else {
3973 oop class_loader = loader_data->class_loader();
3974 info_stream.print(" source: %s", class_loader->klass()->external_name());
3975 }
3976 } else {
3977 assert(this->in_aot_cache(), "must be");
3978 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
3979 info_stream.print(" source: shared objects file (top)");
3980 } else {
3981 info_stream.print(" source: shared objects file");
3982 }
3983 }
3984
3985 msg.info("%s", info_stream.as_string());
3986
3987 if (log_is_enabled(Debug, class, load)) {
3988 stringStream debug_stream;
3989
3990 // Class hierarchy info
3991 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
3992 p2i(this), p2i(super()));
3993
3994 // Interfaces
3995 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
3996 debug_stream.print(" interfaces:");
3997 int length = local_interfaces()->length();
3998 for (int i = 0; i < length; i++) {
3999 debug_stream.print(" " PTR_FORMAT,
4000 p2i(local_interfaces()->at(i)));
4001 }
4002 }
4003
4004 // Class loader
4005 debug_stream.print(" loader: [");
4006 loader_data->print_value_on(&debug_stream);
4007 debug_stream.print("]");
4008
4009 // Classfile checksum
4010 if (cfs) {
4011 debug_stream.print(" bytes: %d checksum: %08x",
4012 cfs->length(),
4013 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4014 cfs->length()));
4015 }
4016
4017 msg.debug("%s", debug_stream.as_string());
4018 }
4019 }
4020
4021 void InstanceKlass::print_class_load_cause_logging() const {
4022 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4023 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4024 JavaThread* current = JavaThread::current();
4025 ResourceMark rm(current);
4026 const char* name = external_name();
4027
4028 if (LogClassLoadingCauseFor == nullptr ||
4029 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4030 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4031 return;
4032 }
4033
4034 // Log Java stack first
4035 {
4036 LogMessage(class, load, cause) msg;
4037 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4038
4039 info_stream.print_cr("Java stack when loading %s:", name);
4040 current->print_stack_on(&info_stream);
4041 }
4042
4043 // Log native stack second
4044 if (log_cause_native) {
4045 // Log to string first so that lines can be indented
4046 stringStream stack_stream;
4047 char buf[O_BUFLEN];
4048 address lastpc = nullptr;
4049 NativeStackPrinter nsp(current);
4050 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4051 true /* print_source_info */, -1 /* max stack */);
4052
4053 LogMessage(class, load, cause, native) msg;
4054 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4055 info_stream.print_cr("Native stack when loading %s:", name);
4056
4057 // Print each native stack line to the log
4058 int size = (int) stack_stream.size();
4059 char* stack = stack_stream.as_string();
4060 char* stack_end = stack + size;
4061 char* line_start = stack;
4062 for (char* p = stack; p < stack_end; p++) {
4063 if (*p == '\n') {
4064 *p = '\0';
4065 info_stream.print_cr("\t%s", line_start);
4066 line_start = p + 1;
4067 }
4068 }
4069 if (line_start < stack_end) {
4070 info_stream.print_cr("\t%s", line_start);
4071 }
4072 }
4073 }
4074 }
4075
4076 // Verification
4077
4078 class VerifyFieldClosure: public BasicOopIterateClosure {
4079 protected:
4080 template <class T> void do_oop_work(T* p) {
4081 oop obj = RawAccess<>::oop_load(p);
4082 if (!oopDesc::is_oop_or_null(obj)) {
4083 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4084 Universe::print_on(tty);
4085 guarantee(false, "boom");
4086 }
4087 }
4088 public:
4089 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4090 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4091 };
4092
4093 void InstanceKlass::verify_on(outputStream* st) {
4094 #ifndef PRODUCT
4095 // Avoid redundant verifies, this really should be in product.
4096 if (_verify_count == Universe::verify_count()) return;
4097 _verify_count = Universe::verify_count();
4098 #endif
4099
4100 // Verify Klass
4101 Klass::verify_on(st);
4102
4103 // Verify that klass is present in ClassLoaderData
4104 guarantee(class_loader_data()->contains_klass(this),
4105 "this class isn't found in class loader data");
4106
4107 // Verify vtables
4108 if (is_linked()) {
4109 // $$$ This used to be done only for m/s collections. Doing it
4110 // always seemed a valid generalization. (DLD -- 6/00)
4111 vtable().verify(st);
4112 }
4113
4114 // Verify first subklass
4115 if (subklass() != nullptr) {
4116 guarantee(subklass()->is_klass(), "should be klass");
4117 }
4118
4119 // Verify siblings
4120 Klass* super = this->super();
4121 Klass* sib = next_sibling();
4122 if (sib != nullptr) {
4123 if (sib == this) {
4124 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4125 }
4126
4127 guarantee(sib->is_klass(), "should be klass");
4128 guarantee(sib->super() == super, "siblings should have same superklass");
4129 }
4130
4131 // Verify local interfaces
4132 if (local_interfaces()) {
4133 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4134 for (int j = 0; j < local_interfaces->length(); j++) {
4135 InstanceKlass* e = local_interfaces->at(j);
4136 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4137 }
4138 }
4139
4140 // Verify transitive interfaces
4141 if (transitive_interfaces() != nullptr) {
4142 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4143 for (int j = 0; j < transitive_interfaces->length(); j++) {
4144 InstanceKlass* e = transitive_interfaces->at(j);
4145 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4146 }
4147 }
4148
4149 // Verify methods
4150 if (methods() != nullptr) {
4151 Array<Method*>* methods = this->methods();
4152 for (int j = 0; j < methods->length(); j++) {
4153 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4154 }
4155 for (int j = 0; j < methods->length() - 1; j++) {
4156 Method* m1 = methods->at(j);
4157 Method* m2 = methods->at(j + 1);
4158 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4159 }
4160 }
4161
4162 // Verify method ordering
4163 if (method_ordering() != nullptr) {
4164 Array<int>* method_ordering = this->method_ordering();
4165 int length = method_ordering->length();
4166 if (JvmtiExport::can_maintain_original_method_order() ||
4167 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4168 guarantee(length == methods()->length(), "invalid method ordering length");
4169 jlong sum = 0;
4170 for (int j = 0; j < length; j++) {
4171 int original_index = method_ordering->at(j);
4172 guarantee(original_index >= 0, "invalid method ordering index");
4173 guarantee(original_index < length, "invalid method ordering index");
4174 sum += original_index;
4175 }
4176 // Verify sum of indices 0,1,...,length-1
4177 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4178 } else {
4179 guarantee(length == 0, "invalid method ordering length");
4180 }
4181 }
4182
4183 // Verify default methods
4184 if (default_methods() != nullptr) {
4185 Array<Method*>* methods = this->default_methods();
4186 for (int j = 0; j < methods->length(); j++) {
4187 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4188 }
4189 for (int j = 0; j < methods->length() - 1; j++) {
4190 Method* m1 = methods->at(j);
4191 Method* m2 = methods->at(j + 1);
4192 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4193 }
4194 }
4195
4196 // Verify JNI static field identifiers
4197 if (jni_ids() != nullptr) {
4198 jni_ids()->verify(this);
4199 }
4200
4201 // Verify other fields
4202 if (constants() != nullptr) {
4203 guarantee(constants()->is_constantPool(), "should be constant pool");
4204 }
4205 }
4206
4207 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4208 Klass::oop_verify_on(obj, st);
4209 VerifyFieldClosure blk;
4210 obj->oop_iterate(&blk);
4211 }
4212
4213 // JNIid class for jfieldIDs only
4214 // Note to reviewers:
4215 // These JNI functions are just moved over to column 1 and not changed
4216 // in the compressed oops workspace.
4217 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4218 _holder = holder;
4219 _offset = offset;
4220 _next = next;
4221 DEBUG_ONLY(_is_static_field_id = false;)
4222 }
4223
4224 JNIid* JNIid::find(int offset) {
4225 JNIid* current = this;
4226 while (current != nullptr) {
4227 if (current->offset() == offset) return current;
4228 current = current->next();
4229 }
4230 return nullptr;
4231 }
4232
4233 void JNIid::deallocate(JNIid* current) {
4234 while (current != nullptr) {
4235 JNIid* next = current->next();
4236 delete current;
4237 current = next;
4238 }
4239 }
4240
4241 void JNIid::verify(InstanceKlass* holder) {
4242 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4243 int end_field_offset;
4244 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4245
4246 JNIid* current = this;
4247 while (current != nullptr) {
4248 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4249 #ifdef ASSERT
4250 int o = current->offset();
4251 if (current->is_static_field_id()) {
4252 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4253 }
4254 #endif
4255 current = current->next();
4256 }
4257 }
4258
4259 void InstanceKlass::set_init_state(ClassState state) {
4260 #ifdef ASSERT
4261 bool good_state = in_aot_cache() ? (_init_state <= state)
4262 : (_init_state < state);
4263 assert(good_state || state == allocated, "illegal state transition");
4264 #endif
4265 assert(_init_thread == nullptr, "should be cleared before state change");
4266 AtomicAccess::release_store(&_init_state, state);
4267 }
4268
4269 #if INCLUDE_JVMTI
4270
4271 // RedefineClasses() support for previous versions
4272
4273 // Globally, there is at least one previous version of a class to walk
4274 // during class unloading, which is saved because old methods in the class
4275 // are still running. Otherwise the previous version list is cleaned up.
4276 bool InstanceKlass::_should_clean_previous_versions = false;
4277
4278 // Returns true if there are previous versions of a class for class
4279 // unloading only. Also resets the flag to false. purge_previous_version
4280 // will set the flag to true if there are any left, i.e., if there's any
4281 // work to do for next time. This is to avoid the expensive code cache
4282 // walk in CLDG::clean_deallocate_lists().
4283 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4284 bool ret = _should_clean_previous_versions;
4285 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4286 ret ? "true" : "false");
4287 _should_clean_previous_versions = false;
4288 return ret;
4289 }
4290
4291 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4292 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4293 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4294 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4295 Array<Method*>* method_refs = klass->methods();
4296 for (int k = 0; k < method_refs->length(); k++) {
4297 Method* method = method_refs->at(k);
4298 // Only need to clear obsolete methods.
4299 if (method != nullptr && method->is_obsolete()) {
4300 method->clear_jmethod_id();
4301 }
4302 }
4303 }
4304
4305 // Purge previous versions before adding new previous versions of the class and
4306 // during class unloading.
4307 void InstanceKlass::purge_previous_version_list() {
4308 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4309 assert(has_been_redefined(), "Should only be called for main class");
4310
4311 // Quick exit.
4312 if (previous_versions() == nullptr) {
4313 return;
4314 }
4315
4316 // This klass has previous versions so see what we can cleanup
4317 // while it is safe to do so.
4318
4319 int deleted_count = 0; // leave debugging breadcrumbs
4320 int live_count = 0;
4321 ClassLoaderData* loader_data = class_loader_data();
4322 assert(loader_data != nullptr, "should never be null");
4323
4324 ResourceMark rm;
4325 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4326
4327 // previous versions are linked together through the InstanceKlass
4328 InstanceKlass* pv_node = previous_versions();
4329 InstanceKlass* last = this;
4330 int version = 0;
4331
4332 // check the previous versions list
4333 for (; pv_node != nullptr; ) {
4334
4335 ConstantPool* pvcp = pv_node->constants();
4336 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4337
4338 if (!pvcp->on_stack()) {
4339 // If the constant pool isn't on stack, none of the methods
4340 // are executing. Unlink this previous_version.
4341 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4342 // so will be deallocated during the next phase of class unloading.
4343 log_trace(redefine, class, iklass, purge)
4344 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4345 // Unlink from previous version list.
4346 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4347 InstanceKlass* next = pv_node->previous_versions();
4348 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4349 pv_node->link_previous_versions(nullptr); // point next to null
4350 last->link_previous_versions(next);
4351 // Delete this node directly. Nothing is referring to it and we don't
4352 // want it to increase the counter for metadata to delete in CLDG.
4353 MetadataFactory::free_metadata(loader_data, pv_node);
4354 pv_node = next;
4355 deleted_count++;
4356 version++;
4357 continue;
4358 } else {
4359 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4360 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4361 live_count++;
4362 if (pvcp->in_aot_cache()) {
4363 // Shared previous versions can never be removed so no cleaning is needed.
4364 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4365 } else {
4366 // Previous version alive, set that clean is needed for next time.
4367 _should_clean_previous_versions = true;
4368 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4369 }
4370 }
4371
4372 // next previous version
4373 last = pv_node;
4374 pv_node = pv_node->previous_versions();
4375 version++;
4376 }
4377 log_trace(redefine, class, iklass, purge)
4378 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4379 }
4380
4381 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4382 int emcp_method_count) {
4383 int obsolete_method_count = old_methods->length() - emcp_method_count;
4384
4385 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4386 _previous_versions != nullptr) {
4387 // We have a mix of obsolete and EMCP methods so we have to
4388 // clear out any matching EMCP method entries the hard way.
4389 int local_count = 0;
4390 for (int i = 0; i < old_methods->length(); i++) {
4391 Method* old_method = old_methods->at(i);
4392 if (old_method->is_obsolete()) {
4393 // only obsolete methods are interesting
4394 Symbol* m_name = old_method->name();
4395 Symbol* m_signature = old_method->signature();
4396
4397 // previous versions are linked together through the InstanceKlass
4398 int j = 0;
4399 for (InstanceKlass* prev_version = _previous_versions;
4400 prev_version != nullptr;
4401 prev_version = prev_version->previous_versions(), j++) {
4402
4403 Array<Method*>* method_refs = prev_version->methods();
4404 for (int k = 0; k < method_refs->length(); k++) {
4405 Method* method = method_refs->at(k);
4406
4407 if (!method->is_obsolete() &&
4408 method->name() == m_name &&
4409 method->signature() == m_signature) {
4410 // The current RedefineClasses() call has made all EMCP
4411 // versions of this method obsolete so mark it as obsolete
4412 log_trace(redefine, class, iklass, add)
4413 ("%s(%s): flush obsolete method @%d in version @%d",
4414 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4415
4416 method->set_is_obsolete();
4417 break;
4418 }
4419 }
4420
4421 // The previous loop may not find a matching EMCP method, but
4422 // that doesn't mean that we can optimize and not go any
4423 // further back in the PreviousVersion generations. The EMCP
4424 // method for this generation could have already been made obsolete,
4425 // but there still may be an older EMCP method that has not
4426 // been made obsolete.
4427 }
4428
4429 if (++local_count >= obsolete_method_count) {
4430 // no more obsolete methods so bail out now
4431 break;
4432 }
4433 }
4434 }
4435 }
4436 }
4437
4438 // Save the scratch_class as the previous version if any of the methods are running.
4439 // The previous_versions are used to set breakpoints in EMCP methods and they are
4440 // also used to clean MethodData links to redefined methods that are no longer running.
4441 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4442 int emcp_method_count) {
4443 assert(Thread::current()->is_VM_thread(),
4444 "only VMThread can add previous versions");
4445
4446 ResourceMark rm;
4447 log_trace(redefine, class, iklass, add)
4448 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4449
4450 // Clean out old previous versions for this class
4451 purge_previous_version_list();
4452
4453 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4454 // a previous redefinition may be made obsolete by this redefinition.
4455 Array<Method*>* old_methods = scratch_class->methods();
4456 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4457
4458 // If the constant pool for this previous version of the class
4459 // is not marked as being on the stack, then none of the methods
4460 // in this previous version of the class are on the stack so
4461 // we don't need to add this as a previous version.
4462 ConstantPool* cp_ref = scratch_class->constants();
4463 if (!cp_ref->on_stack()) {
4464 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4465 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4466 return;
4467 }
4468
4469 // Add previous version if any methods are still running or if this is
4470 // a shared class which should never be removed.
4471 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4472 scratch_class->link_previous_versions(previous_versions());
4473 link_previous_versions(scratch_class);
4474 if (cp_ref->in_aot_cache()) {
4475 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4476 } else {
4477 // We only set clean_previous_versions flag for processing during class
4478 // unloading for non-shared classes.
4479 _should_clean_previous_versions = true;
4480 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4481 }
4482 } // end add_previous_version()
4483
4484 #endif // INCLUDE_JVMTI
4485
4486 Method* InstanceKlass::method_with_idnum(int idnum) const {
4487 Method* m = nullptr;
4488 if (idnum < methods()->length()) {
4489 m = methods()->at(idnum);
4490 }
4491 if (m == nullptr || m->method_idnum() != idnum) {
4492 for (int index = 0; index < methods()->length(); ++index) {
4493 m = methods()->at(index);
4494 if (m->method_idnum() == idnum) {
4495 return m;
4496 }
4497 }
4498 // None found, return null for the caller to handle.
4499 return nullptr;
4500 }
4501 return m;
4502 }
4503
4504
4505 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4506 if (idnum >= methods()->length()) {
4507 return nullptr;
4508 }
4509 Method* m = methods()->at(idnum);
4510 if (m != nullptr && m->orig_method_idnum() == idnum) {
4511 return m;
4512 }
4513 // Obsolete method idnum does not match the original idnum
4514 for (int index = 0; index < methods()->length(); ++index) {
4515 m = methods()->at(index);
4516 if (m->orig_method_idnum() == idnum) {
4517 return m;
4518 }
4519 }
4520 // None found, return null for the caller to handle.
4521 return nullptr;
4522 }
4523
4524
4525 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4526 const InstanceKlass* holder = get_klass_version(version);
4527 if (holder == nullptr) {
4528 return nullptr; // The version of klass is gone, no method is found
4529 }
4530 return holder->method_with_orig_idnum(idnum);
4531 }
4532
4533 #if INCLUDE_JVMTI
4534 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4535 return _cached_class_file;
4536 }
4537
4538 jint InstanceKlass::get_cached_class_file_len() {
4539 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4540 }
4541
4542 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4543 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4544 }
4545 #endif
4546
4547 // Make a step iterating over the class hierarchy under the root class.
4548 // Skips subclasses if requested.
4549 void ClassHierarchyIterator::next() {
4550 assert(_current != nullptr, "required");
4551 if (_visit_subclasses && _current->subklass() != nullptr) {
4552 _current = _current->subklass();
4553 return; // visit next subclass
4554 }
4555 _visit_subclasses = true; // reset
4556 while (_current->next_sibling() == nullptr && _current != _root) {
4557 _current = _current->java_super(); // backtrack; no more sibling subclasses left
4558 }
4559 if (_current == _root) {
4560 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4561 _current = nullptr;
4562 return;
4563 }
4564 _current = _current->next_sibling();
4565 return; // visit next sibling subclass
4566 }