1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "cds/archiveUtils.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/cdsEnumKlass.hpp"
29 #include "cds/classListWriter.hpp"
30 #include "cds/heapShared.hpp"
31 #include "cds/metaspaceShared.hpp"
32 #include "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeHistogram.hpp"
49 #include "interpreter/bytecodeStream.hpp"
50 #include "interpreter/oopMapCache.hpp"
51 #include "interpreter/rewriter.hpp"
52 #include "jvm.h"
53 #include "jvmtifiles/jvmti.h"
54 #include "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/fieldStreams.inline.hpp"
65 #include "oops/constantPool.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 "oops/trainingData.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/synchronizer.hpp"
93 #include "runtime/threads.hpp"
94 #include "services/classLoadingService.hpp"
95 #include "services/finalizerService.hpp"
96 #include "services/threadService.hpp"
97 #include "utilities/dtrace.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/macros.hpp"
100 #include "utilities/stringUtils.hpp"
101 #include "utilities/pair.hpp"
102 #ifdef COMPILER1
103 #include "c1/c1_Compiler.hpp"
104 #endif
105 #if INCLUDE_JFR
106 #include "jfr/jfrEvents.hpp"
107 #endif
108
109 #ifdef DTRACE_ENABLED
110
111
112 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
113 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
114 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
115 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
116 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
117 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
118 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
119 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
120 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
121 { \
122 char* data = nullptr; \
123 int len = 0; \
124 Symbol* clss_name = name(); \
125 if (clss_name != nullptr) { \
126 data = (char*)clss_name->bytes(); \
127 len = clss_name->utf8_length(); \
128 } \
129 HOTSPOT_CLASS_INITIALIZATION_##type( \
130 data, len, (void*)class_loader(), thread_type); \
131 }
132
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
134 { \
135 char* data = nullptr; \
136 int len = 0; \
137 Symbol* clss_name = name(); \
138 if (clss_name != nullptr) { \
139 data = (char*)clss_name->bytes(); \
140 len = clss_name->utf8_length(); \
141 } \
142 HOTSPOT_CLASS_INITIALIZATION_##type( \
143 data, len, (void*)class_loader(), thread_type, wait); \
144 }
145
146 #else // ndef DTRACE_ENABLED
147
148 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
149 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
150
151 #endif // ndef DTRACE_ENABLED
152
153 bool InstanceKlass::_finalization_enabled = true;
154
155 static inline bool is_class_loader(const Symbol* class_name,
156 const ClassFileParser& parser) {
157 assert(class_name != nullptr, "invariant");
158
159 if (class_name == vmSymbols::java_lang_ClassLoader()) {
160 return true;
161 }
162
163 if (vmClasses::ClassLoader_klass_loaded()) {
164 const Klass* const super_klass = parser.super_klass();
165 if (super_klass != nullptr) {
166 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
167 return true;
168 }
169 }
170 }
171 return false;
172 }
173
174 static inline bool is_stack_chunk_class(const Symbol* class_name,
175 const ClassLoaderData* loader_data) {
176 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
177 loader_data->is_the_null_class_loader_data());
178 }
179
180 // private: called to verify that k is a static member of this nest.
181 // We know that k is an instance class in the same package and hence the
182 // same classloader.
183 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
184 assert(!is_hidden(), "unexpected hidden class");
185 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
186 if (log_is_enabled(Trace, class, nestmates)) {
187 ResourceMark rm(current);
188 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
189 k->external_name(), this->external_name());
190 }
191 return false;
192 }
193
194 if (log_is_enabled(Trace, class, nestmates)) {
195 ResourceMark rm(current);
196 log_trace(class, nestmates)("Checking nest membership of %s in %s",
197 k->external_name(), this->external_name());
198 }
199
200 // Check for the named class in _nest_members.
201 // We don't resolve, or load, any classes.
202 for (int i = 0; i < _nest_members->length(); i++) {
203 int cp_index = _nest_members->at(i);
204 Symbol* name = _constants->klass_name_at(cp_index);
205 if (name == k->name()) {
206 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
207 return true;
208 }
209 }
210 log_trace(class, nestmates)("- class is NOT a nest member!");
211 return false;
212 }
213
214 // Called to verify that k is a permitted subclass of this class
215 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
216 Thread* current = Thread::current();
217 assert(k != nullptr, "sanity check");
218 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
219 "unexpected empty _permitted_subclasses array");
220
221 if (log_is_enabled(Trace, class, sealed)) {
222 ResourceMark rm(current);
223 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
224 k->external_name(), this->external_name());
225 }
226
227 // Check that the class and its super are in the same module.
228 if (k->module() != this->module()) {
229 ResourceMark rm(current);
230 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
231 k->external_name(), this->external_name());
232 return false;
233 }
234
235 if (!k->is_public() && !is_same_class_package(k)) {
236 ResourceMark rm(current);
237 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
238 k->external_name(), this->external_name());
239 return false;
240 }
241
242 for (int i = 0; i < _permitted_subclasses->length(); i++) {
243 int cp_index = _permitted_subclasses->at(i);
244 Symbol* name = _constants->klass_name_at(cp_index);
245 if (name == k->name()) {
246 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
247 return true;
248 }
249 }
250 log_trace(class, sealed)("- class is NOT a permitted subclass!");
251 return false;
252 }
253
254 // Return nest-host class, resolving, validating and saving it if needed.
255 // In cases where this is called from a thread that cannot do classloading
256 // (such as a native JIT thread) then we simply return null, which in turn
257 // causes the access check to return false. Such code will retry the access
258 // from a more suitable environment later. Otherwise the _nest_host is always
259 // set once this method returns.
260 // Any errors from nest-host resolution must be preserved so they can be queried
261 // from higher-level access checking code, and reported as part of access checking
262 // exceptions.
263 // VirtualMachineErrors are propagated with a null return.
264 // Under any conditions where the _nest_host can be set to non-null the resulting
265 // value of it and, if applicable, the nest host resolution/validation error,
266 // are idempotent.
267 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
268 InstanceKlass* nest_host_k = _nest_host;
269 if (nest_host_k != nullptr) {
270 return nest_host_k;
271 }
272
273 ResourceMark rm(THREAD);
274
275 // need to resolve and save our nest-host class.
276 if (_nest_host_index != 0) { // we have a real nest_host
277 // Before trying to resolve check if we're in a suitable context
278 bool can_resolve = THREAD->can_call_java();
279 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
280 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
281 this->external_name());
282 return nullptr; // sentinel to say "try again from a different context"
283 }
284
285 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
286 this->external_name(),
287 _constants->klass_name_at(_nest_host_index)->as_C_string());
288
289 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
290 if (HAS_PENDING_EXCEPTION) {
291 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
292 return nullptr; // propagate VMEs
293 }
294 stringStream ss;
295 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
296 ss.print("Nest host resolution of %s with host %s failed: ",
297 this->external_name(), target_host_class);
298 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
299 const char* msg = ss.as_string(true /* on C-heap */);
300 constantPoolHandle cph(THREAD, constants());
301 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
302 CLEAR_PENDING_EXCEPTION;
303
304 log_trace(class, nestmates)("%s", msg);
305 } else {
306 // A valid nest-host is an instance class in the current package that lists this
307 // class as a nest member. If any of these conditions are not met the class is
308 // its own nest-host.
309 const char* error = nullptr;
310
311 // JVMS 5.4.4 indicates package check comes first
312 if (is_same_class_package(k)) {
313 // Now check actual membership. We can't be a member if our "host" is
314 // not an instance class.
315 if (k->is_instance_klass()) {
316 nest_host_k = InstanceKlass::cast(k);
317 bool is_member = nest_host_k->has_nest_member(THREAD, this);
318 if (is_member) {
319 _nest_host = nest_host_k; // save resolved nest-host value
320
321 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
322 this->external_name(), k->external_name());
323 return nest_host_k;
324 } else {
325 error = "current type is not listed as a nest member";
326 }
327 } else {
328 error = "host is not an instance class";
329 }
330 } else {
331 error = "types are in different packages";
332 }
333
334 // something went wrong, so record what and log it
335 {
336 stringStream ss;
337 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
338 this->external_name(),
339 this->class_loader_data()->loader_name_and_id(),
340 k->external_name(),
341 k->class_loader_data()->loader_name_and_id(),
342 error);
343 const char* msg = ss.as_string(true /* on C-heap */);
344 constantPoolHandle cph(THREAD, constants());
345 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
346 log_trace(class, nestmates)("%s", msg);
347 }
348 }
349 } else {
350 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
351 this->external_name());
352 }
353
354 // Either not in an explicit nest, or else an error occurred, so
355 // the nest-host is set to `this`. Any thread that sees this assignment
356 // will also see any setting of nest_host_error(), if applicable.
357 return (_nest_host = this);
358 }
359
360 // Dynamic nest member support: set this class's nest host to the given class.
361 // This occurs as part of the class definition, as soon as the instanceKlass
362 // has been created and doesn't require further resolution. The code:
363 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
364 // results in:
365 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
366 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
367 // We also know the "host" is a valid nest-host in the same package so we can
368 // assert some of those facts.
369 void InstanceKlass::set_nest_host(InstanceKlass* host) {
370 assert(is_hidden(), "must be a hidden class");
371 assert(host != nullptr, "null nest host specified");
372 assert(_nest_host == nullptr, "current class has resolved nest-host");
373 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
374 nest_host_error());
375 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
376 (host->_nest_host == host), "proposed host is not a valid nest-host");
377 // Can't assert this as package is not set yet:
378 // assert(is_same_class_package(host), "proposed host is in wrong package");
379
380 if (log_is_enabled(Trace, class, nestmates)) {
381 ResourceMark rm;
382 const char* msg = "";
383 // a hidden class does not expect a statically defined nest-host
384 if (_nest_host_index > 0) {
385 msg = "(the NestHost attribute in the current class is ignored)";
386 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
387 msg = "(the NestMembers attribute in the current class is ignored)";
388 }
389 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
390 this->external_name(),
391 host->external_name(),
392 msg);
393 }
394 // set dynamic nest host
395 _nest_host = host;
396 // Record dependency to keep nest host from being unloaded before this class.
397 ClassLoaderData* this_key = class_loader_data();
398 assert(this_key != nullptr, "sanity");
399 this_key->record_dependency(host);
400 }
401
402 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
403 // or we are k's nest_host - all of which is covered by comparing the two
404 // resolved_nest_hosts.
405 // Any exceptions (i.e. VMEs) are propagated.
406 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
407
408 assert(this != k, "this should be handled by higher-level code");
409
410 // Per JVMS 5.4.4 we first resolve and validate the current class, then
411 // the target class k.
412
413 InstanceKlass* cur_host = nest_host(CHECK_false);
414 if (cur_host == nullptr) {
415 return false;
416 }
417
418 Klass* k_nest_host = k->nest_host(CHECK_false);
419 if (k_nest_host == nullptr) {
420 return false;
421 }
422
423 bool access = (cur_host == k_nest_host);
424
425 ResourceMark rm(THREAD);
426 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
427 this->external_name(),
428 access ? "" : "NOT ",
429 k->external_name());
430 return access;
431 }
432
433 const char* InstanceKlass::nest_host_error() {
434 if (_nest_host_index == 0) {
435 return nullptr;
436 } else {
437 constantPoolHandle cph(Thread::current(), constants());
438 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
439 }
440 }
441
442 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
443 bool use_class_space, TRAPS) throw() {
444 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
445 }
446
447 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
448 const int size = InstanceKlass::size(parser.vtable_size(),
449 parser.itable_size(),
450 nonstatic_oop_map_size(parser.total_oop_map_count()),
451 parser.is_interface());
452
453 const Symbol* const class_name = parser.class_name();
454 assert(class_name != nullptr, "invariant");
455 ClassLoaderData* loader_data = parser.loader_data();
456 assert(loader_data != nullptr, "invariant");
457
458 InstanceKlass* ik;
459 const bool use_class_space = !parser.is_interface() && !parser.is_abstract();
460
461 // Allocation
462 if (parser.is_instance_ref_klass()) {
463 // java.lang.ref.Reference
464 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
465 } else if (class_name == vmSymbols::java_lang_Class()) {
466 // mirror - java.lang.Class
467 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
468 } else if (is_stack_chunk_class(class_name, loader_data)) {
469 // stack chunk
470 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
471 } else if (is_class_loader(class_name, parser)) {
472 // class loader - java.lang.ClassLoader
473 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
474 } else {
475 // normal
476 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
477 }
478
479 // Check for pending exception before adding to the loader data and incrementing
480 // class count. Can get OOM here.
481 if (HAS_PENDING_EXCEPTION) {
482 return nullptr;
483 }
484
485 return ik;
486 }
487
488
489 // copy method ordering from resource area to Metaspace
490 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
491 if (m != nullptr) {
492 // allocate a new array and copy contents (memcpy?)
493 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
494 for (int i = 0; i < m->length(); i++) {
495 _method_ordering->at_put(i, m->at(i));
496 }
497 } else {
498 _method_ordering = Universe::the_empty_int_array();
499 }
500 }
501
502 // create a new array of vtable_indices for default methods
503 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
504 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
505 assert(default_vtable_indices() == nullptr, "only create once");
506 set_default_vtable_indices(vtable_indices);
507 return vtable_indices;
508 }
509
510
511 InstanceKlass::InstanceKlass() {
512 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
513 }
514
515 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
516 Klass(kind),
517 _nest_members(nullptr),
518 _nest_host(nullptr),
519 _permitted_subclasses(nullptr),
520 _record_components(nullptr),
521 _static_field_size(parser.static_field_size()),
522 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
523 _itable_len(parser.itable_size()),
524 _nest_host_index(0),
525 _init_state(allocated),
526 _reference_type(reference_type),
527 _init_thread(nullptr)
528 {
529 set_vtable_length(parser.vtable_size());
530 set_access_flags(parser.access_flags());
531 if (parser.is_hidden()) set_is_hidden();
532 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
533 false));
534
535 assert(nullptr == _methods, "underlying memory not zeroed?");
536 assert(is_instance_klass(), "is layout incorrect?");
537 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
538 }
539
540 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
541 Array<Method*>* methods) {
542 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
543 !methods->is_shared()) {
544 for (int i = 0; i < methods->length(); i++) {
545 Method* method = methods->at(i);
546 if (method == nullptr) continue; // maybe null if error processing
547 // Only want to delete methods that are not executing for RedefineClasses.
548 // The previous version will point to them so they're not totally dangling
549 assert (!method->on_stack(), "shouldn't be called with methods on stack");
550 MetadataFactory::free_metadata(loader_data, method);
551 }
552 MetadataFactory::free_array<Method*>(loader_data, methods);
553 }
554 }
555
556 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
557 const Klass* super_klass,
558 Array<InstanceKlass*>* local_interfaces,
559 Array<InstanceKlass*>* transitive_interfaces) {
560 // Only deallocate transitive interfaces if not empty, same as super class
561 // or same as local interfaces. See code in parseClassFile.
562 Array<InstanceKlass*>* ti = transitive_interfaces;
563 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
564 // check that the interfaces don't come from super class
565 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
566 InstanceKlass::cast(super_klass)->transitive_interfaces();
567 if (ti != sti && ti != nullptr && !ti->is_shared()) {
568 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
569 }
570 }
571
572 // local interfaces can be empty
573 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
574 local_interfaces != nullptr && !local_interfaces->is_shared()) {
575 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
576 }
577 }
578
579 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
580 Array<RecordComponent*>* record_components) {
581 if (record_components != nullptr && !record_components->is_shared()) {
582 for (int i = 0; i < record_components->length(); i++) {
583 RecordComponent* record_component = record_components->at(i);
584 MetadataFactory::free_metadata(loader_data, record_component);
585 }
586 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
587 }
588 }
589
590 // This function deallocates the metadata and C heap pointers that the
591 // InstanceKlass points to.
592 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
593 #if INCLUDE_CDS_JAVA_HEAP
594 if (CDSConfig::is_dumping_heap()) {
595 HeapShared::remove_scratch_objects(this);
596 }
597 #endif
598
599 // Orphan the mirror first, CMS thinks it's still live.
600 if (java_mirror() != nullptr) {
601 java_lang_Class::set_klass(java_mirror(), nullptr);
602 }
603
604 // Also remove mirror from handles
605 loader_data->remove_handle(_java_mirror);
606
607 // Need to take this class off the class loader data list.
608 loader_data->remove_class(this);
609
610 // The array_klass for this class is created later, after error handling.
611 // For class redefinition, we keep the original class so this scratch class
612 // doesn't have an array class. Either way, assert that there is nothing
613 // to deallocate.
614 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
615
616 // Release C heap allocated data that this points to, which includes
617 // reference counting symbol names.
618 // Can't release the constant pool or MethodData C heap data here because the constant
619 // pool can be deallocated separately from the InstanceKlass for default methods and
620 // redefine classes. MethodData can also be released separately.
621 release_C_heap_structures(/* release_sub_metadata */ false);
622
623 deallocate_methods(loader_data, methods());
624 set_methods(nullptr);
625
626 deallocate_record_components(loader_data, record_components());
627 set_record_components(nullptr);
628
629 if (method_ordering() != nullptr &&
630 method_ordering() != Universe::the_empty_int_array() &&
631 !method_ordering()->is_shared()) {
632 MetadataFactory::free_array<int>(loader_data, method_ordering());
633 }
634 set_method_ordering(nullptr);
635
636 // default methods can be empty
637 if (default_methods() != nullptr &&
638 default_methods() != Universe::the_empty_method_array() &&
639 !default_methods()->is_shared()) {
640 MetadataFactory::free_array<Method*>(loader_data, default_methods());
641 }
642 // Do NOT deallocate the default methods, they are owned by superinterfaces.
643 set_default_methods(nullptr);
644
645 // default methods vtable indices can be empty
646 if (default_vtable_indices() != nullptr &&
647 !default_vtable_indices()->is_shared()) {
648 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
649 }
650 set_default_vtable_indices(nullptr);
651
652
653 // This array is in Klass, but remove it with the InstanceKlass since
654 // this place would be the only caller and it can share memory with transitive
655 // interfaces.
656 if (secondary_supers() != nullptr &&
657 secondary_supers() != Universe::the_empty_klass_array() &&
658 // see comments in compute_secondary_supers about the following cast
659 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
660 !secondary_supers()->is_shared()) {
661 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
662 }
663 set_secondary_supers(nullptr);
664
665 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
666 set_transitive_interfaces(nullptr);
667 set_local_interfaces(nullptr);
668
669 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
670 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
671 }
672 set_fieldinfo_stream(nullptr);
673
674 if (fields_status() != nullptr && !fields_status()->is_shared()) {
675 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
676 }
677 set_fields_status(nullptr);
678
679 // If a method from a redefined class is using this constant pool, don't
680 // delete it, yet. The new class's previous version will point to this.
681 if (constants() != nullptr) {
682 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
683 if (!constants()->is_shared()) {
684 MetadataFactory::free_metadata(loader_data, constants());
685 }
686 // Delete any cached resolution errors for the constant pool
687 SystemDictionary::delete_resolution_error(constants());
688
689 set_constants(nullptr);
690 }
691
692 if (inner_classes() != nullptr &&
693 inner_classes() != Universe::the_empty_short_array() &&
694 !inner_classes()->is_shared()) {
695 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
696 }
697 set_inner_classes(nullptr);
698
699 if (nest_members() != nullptr &&
700 nest_members() != Universe::the_empty_short_array() &&
701 !nest_members()->is_shared()) {
702 MetadataFactory::free_array<jushort>(loader_data, nest_members());
703 }
704 set_nest_members(nullptr);
705
706 if (permitted_subclasses() != nullptr &&
707 permitted_subclasses() != Universe::the_empty_short_array() &&
708 !permitted_subclasses()->is_shared()) {
709 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
710 }
711 set_permitted_subclasses(nullptr);
712
713 // We should deallocate the Annotations instance if it's not in shared spaces.
714 if (annotations() != nullptr && !annotations()->is_shared()) {
715 MetadataFactory::free_metadata(loader_data, annotations());
716 }
717 set_annotations(nullptr);
718
719 SystemDictionaryShared::handle_class_unloading(this);
720 }
721
722 bool InstanceKlass::is_record() const {
723 return _record_components != nullptr &&
724 is_final() &&
725 java_super() == vmClasses::Record_klass();
726 }
727
728 bool InstanceKlass::is_sealed() const {
729 return _permitted_subclasses != nullptr &&
730 _permitted_subclasses != Universe::the_empty_short_array();
731 }
732
733 bool InstanceKlass::should_be_initialized() const {
734 return !is_initialized();
735 }
736
737 klassItable InstanceKlass::itable() const {
738 return klassItable(const_cast<InstanceKlass*>(this));
739 }
740
741 // JVMTI spec thinks there are signers and protection domain in the
742 // instanceKlass. These accessors pretend these fields are there.
743 // The hprof specification also thinks these fields are in InstanceKlass.
744 oop InstanceKlass::protection_domain() const {
745 // return the protection_domain from the mirror
746 return java_lang_Class::protection_domain(java_mirror());
747 }
748
749 objArrayOop InstanceKlass::signers() const {
750 // return the signers from the mirror
751 return java_lang_Class::signers(java_mirror());
752 }
753
754 oop InstanceKlass::init_lock() const {
755 // return the init lock from the mirror
756 oop lock = java_lang_Class::init_lock(java_mirror());
757 // Prevent reordering with any access of initialization state
758 OrderAccess::loadload();
759 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
760 "only fully initialized state can have a null lock");
761 return lock;
762 }
763
764 // Set the initialization lock to null so the object can be GC'ed. Any racing
765 // threads to get this lock will see a null lock and will not lock.
766 // That's okay because they all check for initialized state after getting
767 // the lock and return.
768 void InstanceKlass::fence_and_clear_init_lock() {
769 // make sure previous stores are all done, notably the init_state.
770 OrderAccess::storestore();
771 java_lang_Class::clear_init_lock(java_mirror());
772 assert(!is_not_initialized(), "class must be initialized now");
773 }
774
775
776 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
777 // process. The step comments refers to the procedure described in that section.
778 // Note: implementation moved to static method to expose the this pointer.
779 void InstanceKlass::initialize(TRAPS) {
780 if (this->should_be_initialized()) {
781 initialize_impl(CHECK);
782 // Note: at this point the class may be initialized
783 // OR it may be in the state of being initialized
784 // in case of recursive initialization!
785 } else {
786 assert(is_initialized(), "sanity check");
787 }
788 }
789
790 static bool are_super_types_initialized(InstanceKlass* ik) {
791 InstanceKlass* s = ik->java_super();
792 if (s != nullptr && !s->is_initialized()) {
793 if (log_is_enabled(Info, cds, init)) {
794 ResourceMark rm;
795 log_info(cds, init)("%s takes slow path because super class %s is not initialized",
796 ik->external_name(), s->external_name());
797 }
798 return false;
799 }
800
801 if (ik->has_nonstatic_concrete_methods()) {
802 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
803 // having a superinterface that declares, non-static, concrete methods
804 Array<InstanceKlass*>* interfaces = ik->local_interfaces();
805 int len = interfaces->length();
806 for (int i = 0; i < len; i++) {
807 InstanceKlass* intf = interfaces->at(i);
808 if (!intf->is_initialized()) {
809 if (log_is_enabled(Info, cds, init)) {
810 ResourceMark rm;
811 log_info(cds, init)("%s takes slow path because interface %s is not initialized",
812 ik->external_name(), intf->external_name());
813 }
814 return false;
815 }
816 }
817 }
818
819 return true;
820 }
821
822 static void log_class_init_start(outputStream* st, JavaThread* current, InstanceKlass* ik, int init_id) {
823 ResourceMark rm;
824 const char* info = "";
825 if (ik->has_preinitialized_mirror() && CDSConfig::is_loading_heap()) {
826 info = " (preinitialized)";
827 } else if (ik->class_initializer() == nullptr) {
828 info = " (no method)";
829 }
830 st->print("%d Initializing ", init_id);
831 ik->name()->print_value_on(st);
832 st->print_cr("%s (" PTR_FORMAT ") by thread " PTR_FORMAT " \"%s\"", info, p2i(ik), p2i(current), current->name());
833 }
834
835 static int log_class_init(JavaThread* current, InstanceKlass* ik) {
836 int init_id = -1;
837 LogStreamHandle(Info, init, class) lsh1;
838 LogStreamHandle(Debug, init) lsh2;
839 if (lsh1.is_enabled() || lsh2.is_enabled()) {
840 static int call_class_initializer_counter = 0; // for debugging
841 init_id = Atomic::fetch_then_add(&call_class_initializer_counter, 1);
842 if (lsh1.is_enabled()) {
843 log_class_init_start(&lsh1, current, ik, init_id);
844 }
845 if (lsh2.is_enabled() && ik->class_initializer() != nullptr && !ik->has_preinitialized_mirror()) {
846 log_class_init_start(&lsh2, current, ik, init_id);
847 }
848 }
849 return init_id;
850 }
851
852 void InstanceKlass::initialize_from_cds(TRAPS) {
853 if (is_initialized()) {
854 return;
855 }
856
857 if (has_preinitialized_mirror() && CDSConfig::is_loading_heap() &&
858 !ForceProfiling &&
859 !RecordTraining &&
860 are_super_types_initialized(this)) {
861 // FIXME: also check for events listeners such as JVMTI, JFR, etc
862 if (log_is_enabled(Info, cds, init)) {
863 ResourceMark rm;
864 log_info(cds, init)("%s (quickest)", external_name());
865 }
866
867 link_class(CHECK);
868
869 #ifdef AZZERT
870 {
871 MonitorLocker ml(THREAD, _init_monitor);
872 assert(!initialized(), "sanity");
873 assert(!is_being_initialized(), "sanity");
874 assert(!is_in_error_state(), "sanity");
875 }
876 #endif
877
878 log_class_init(THREAD, this);
879 set_init_thread(THREAD);
880 set_initialization_state_and_notify(fully_initialized, CHECK);
881 return;
882 }
883
884 if (log_is_enabled(Info, cds, init)) {
885 ResourceMark rm;
886 log_info(cds, init)("%s%s", external_name(),
887 (has_preinitialized_mirror() && CDSConfig::is_loading_heap()) ? " (quicker)" : "");
888 }
889 initialize(THREAD);
890 }
891
892 bool InstanceKlass::verify_code(TRAPS) {
893 // 1) Verify the bytecodes
894 return Verifier::verify(this, should_verify_class(), THREAD);
895 }
896
897 void InstanceKlass::link_class(TRAPS) {
898 assert(is_loaded(), "must be loaded");
899 if (!is_linked()) {
900 link_class_impl(CHECK);
901 }
902 }
903
904 // Called to verify that a class can link during initialization, without
905 // throwing a VerifyError.
906 bool InstanceKlass::link_class_or_fail(TRAPS) {
907 assert(is_loaded(), "must be loaded");
908 if (!is_linked()) {
909 link_class_impl(CHECK_false);
910 }
911 return is_linked();
912 }
913
914 bool InstanceKlass::link_class_impl(TRAPS) {
915 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
916 // This is for CDS static dump only -- we use the in_error_state to indicate that
917 // the class has failed verification. Throwing the NoClassDefFoundError here is just
918 // a convenient way to stop repeat attempts to verify the same (bad) class.
919 //
920 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
921 // if we are executing Java code. This is not a problem for CDS dumping phase since
922 // it doesn't execute any Java code.
923 ResourceMark rm(THREAD);
924 Exceptions::fthrow(THREAD_AND_LOCATION,
925 vmSymbols::java_lang_NoClassDefFoundError(),
926 "Class %s, or one of its supertypes, failed class initialization",
927 external_name());
928 return false;
929 }
930 // return if already verified
931 if (is_linked()) {
932 return true;
933 }
934
935 // Timing
936 // timer handles recursion
937 JavaThread* jt = THREAD;
938
939 // link super class before linking this class
940 Klass* super_klass = super();
941 if (super_klass != nullptr) {
942 if (super_klass->is_interface()) { // check if super class is an interface
943 ResourceMark rm(THREAD);
944 Exceptions::fthrow(
945 THREAD_AND_LOCATION,
946 vmSymbols::java_lang_IncompatibleClassChangeError(),
947 "class %s has interface %s as super class",
948 external_name(),
949 super_klass->external_name()
950 );
951 return false;
952 }
953
954 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
955 ik_super->link_class_impl(CHECK_false);
956 }
957
958 // link all interfaces implemented by this class before linking this class
959 Array<InstanceKlass*>* interfaces = local_interfaces();
960 int num_interfaces = interfaces->length();
961 for (int index = 0; index < num_interfaces; index++) {
962 InstanceKlass* interk = interfaces->at(index);
963 interk->link_class_impl(CHECK_false);
964 }
965
966 // in case the class is linked in the process of linking its superclasses
967 if (is_linked()) {
968 return true;
969 }
970
971 // trace only the link time for this klass that includes
972 // the verification time
973 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
974 ClassLoader::perf_class_link_selftime(),
975 ClassLoader::perf_classes_linked(),
976 jt->get_thread_stat()->perf_recursion_counts_addr(),
977 jt->get_thread_stat()->perf_timers_addr(),
978 PerfClassTraceTime::CLASS_LINK);
979
980 // verification & rewriting
981 {
982 HandleMark hm(THREAD);
983 Handle h_init_lock(THREAD, init_lock());
984 ObjectLocker ol(h_init_lock, jt);
985 // rewritten will have been set if loader constraint error found
986 // on an earlier link attempt
987 // don't verify or rewrite if already rewritten
988 //
989
990 if (!is_linked()) {
991 if (!is_rewritten()) {
992 if (is_shared()) {
993 assert(!verified_at_dump_time(), "must be");
994 }
995 {
996 bool verify_ok = verify_code(THREAD);
997 if (!verify_ok) {
998 return false;
999 }
1000 }
1001
1002 // Just in case a side-effect of verify linked this class already
1003 // (which can sometimes happen since the verifier loads classes
1004 // using custom class loaders, which are free to initialize things)
1005 if (is_linked()) {
1006 return true;
1007 }
1008
1009 // also sets rewritten
1010 rewrite_class(CHECK_false);
1011 } else if (is_shared()) {
1012 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1013 }
1014
1015 // relocate jsrs and link methods after they are all rewritten
1016 link_methods(CHECK_false);
1017
1018 // Initialize the vtable and interface table after
1019 // methods have been rewritten since rewrite may
1020 // fabricate new Method*s.
1021 // also does loader constraint checking
1022 //
1023 // initialize_vtable and initialize_itable need to be rerun
1024 // for a shared class if
1025 // 1) the class is loaded by custom class loader or
1026 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1027 // 3) the class was not verified during dump time
1028 bool need_init_table = true;
1029 if (is_shared() && verified_at_dump_time() &&
1030 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1031 need_init_table = false;
1032 }
1033 if (need_init_table) {
1034 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1035 itable().initialize_itable_and_check_constraints(CHECK_false);
1036 }
1037 #ifdef ASSERT
1038 vtable().verify(tty, true);
1039 // In case itable verification is ever added.
1040 // itable().verify(tty, true);
1041 #endif
1042 if (Universe::is_fully_initialized()) {
1043 DeoptimizationScope deopt_scope;
1044 {
1045 // Now mark all code that assumes the class is not linked.
1046 // Set state under the Compile_lock also.
1047 MutexLocker ml(THREAD, Compile_lock);
1048
1049 set_init_state(linked);
1050 CodeCache::mark_dependents_on(&deopt_scope, this);
1051 }
1052 // Perform the deopt handshake outside Compile_lock.
1053 deopt_scope.deoptimize_marked();
1054 } else {
1055 set_init_state(linked);
1056 }
1057 if (JvmtiExport::should_post_class_prepare()) {
1058 JvmtiExport::post_class_prepare(THREAD, this);
1059 }
1060 }
1061 }
1062 return true;
1063 }
1064
1065 // Rewrite the byte codes of all of the methods of a class.
1066 // The rewriter must be called exactly once. Rewriting must happen after
1067 // verification but before the first method of the class is executed.
1068 void InstanceKlass::rewrite_class(TRAPS) {
1069 assert(is_loaded(), "must be loaded");
1070 if (is_rewritten()) {
1071 assert(is_shared(), "rewriting an unshared class?");
1072 return;
1073 }
1074 Rewriter::rewrite(this, CHECK);
1075 set_rewritten();
1076 }
1077
1078 // Now relocate and link method entry points after class is rewritten.
1079 // This is outside is_rewritten flag. In case of an exception, it can be
1080 // executed more than once.
1081 void InstanceKlass::link_methods(TRAPS) {
1082 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1083
1084 int len = methods()->length();
1085 for (int i = len-1; i >= 0; i--) {
1086 methodHandle m(THREAD, methods()->at(i));
1087
1088 // Set up method entry points for compiler and interpreter .
1089 m->link_method(m, CHECK);
1090 }
1091 }
1092
1093 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1094 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1095 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1096 for (int i = 0; i < local_interfaces()->length(); ++i) {
1097 InstanceKlass* ik = local_interfaces()->at(i);
1098
1099 // Initialization is depth first search ie. we start with top of the inheritance tree
1100 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1101 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1102 if (ik->has_nonstatic_concrete_methods()) {
1103 ik->initialize_super_interfaces(CHECK);
1104 }
1105
1106 // Only initialize() interfaces that "declare" concrete methods.
1107 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1108 ik->initialize(CHECK);
1109 }
1110 }
1111 }
1112
1113 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1114 static InitializationErrorTable* _initialization_error_table;
1115
1116 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1117 // Create the same exception with a message indicating the thread name,
1118 // and the StackTraceElements.
1119 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1120 ResourceMark rm(current);
1121 if (init_error.is_null()) {
1122 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1123
1124 // We failed to create the new exception, most likely due to either out-of-memory or
1125 // a stackoverflow error. If the original exception was either of those then we save
1126 // the shared, pre-allocated, stackless, instance of that exception.
1127 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1128 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1129 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1130 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1131 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1132 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1133 } else {
1134 return;
1135 }
1136 }
1137
1138 MutexLocker ml(current, ClassInitError_lock);
1139 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1140 bool created;
1141 if (_initialization_error_table == nullptr) {
1142 _initialization_error_table = new (mtClass) InitializationErrorTable();
1143 }
1144 _initialization_error_table->put_if_absent(this, elem, &created);
1145 assert(created, "Initialization is single threaded");
1146 log_trace(class, init)("Initialization error added for class %s", external_name());
1147 }
1148
1149 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1150 MutexLocker ml(current, ClassInitError_lock);
1151 if (_initialization_error_table == nullptr) {
1152 return nullptr;
1153 }
1154 OopHandle* h = _initialization_error_table->get(this);
1155 return (h != nullptr) ? h->resolve() : nullptr;
1156 }
1157
1158 // Need to remove entries for unloaded classes.
1159 void InstanceKlass::clean_initialization_error_table() {
1160 struct InitErrorTableCleaner {
1161 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1162 if (!ik->is_loader_alive()) {
1163 h.release(Universe::vm_global());
1164 return true;
1165 } else {
1166 return false;
1167 }
1168 }
1169 };
1170
1171 assert_locked_or_safepoint(ClassInitError_lock);
1172 InitErrorTableCleaner cleaner;
1173 if (_initialization_error_table != nullptr) {
1174 _initialization_error_table->unlink(&cleaner);
1175 }
1176 }
1177
1178 void InstanceKlass::initialize_impl(TRAPS) {
1179 HandleMark hm(THREAD);
1180
1181 // Make sure klass is linked (verified) before initialization
1182 // A class could already be verified, since it has been reflected upon.
1183 link_class(CHECK);
1184
1185 DTRACE_CLASSINIT_PROBE(required, -1);
1186
1187 bool wait = false;
1188
1189 JavaThread* jt = THREAD;
1190
1191 if (ForceProfiling) {
1192 // Preallocate MDOs.
1193 for (int i = 0; i < methods()->length(); i++) {
1194 assert(!HAS_PENDING_EXCEPTION, "");
1195 methodHandle m(THREAD, methods()->at(i));
1196 Method::build_profiling_method_data(m, THREAD);
1197 if (HAS_PENDING_EXCEPTION) {
1198 ResourceMark rm;
1199 log_warning(cds)("MDO preallocation failed for %s", external_name());
1200 CLEAR_PENDING_EXCEPTION;
1201 break;
1202 }
1203 }
1204 }
1205
1206 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1207
1208 // refer to the JVM book page 47 for description of steps
1209 // Step 1
1210 {
1211 Handle h_init_lock(THREAD, init_lock());
1212 ObjectLocker ol(h_init_lock, jt);
1213
1214 // Step 2
1215 // If we were to use wait() instead of waitInterruptibly() then
1216 // we might end up throwing IE from link/symbol resolution sites
1217 // that aren't expected to throw. This would wreak havoc. See 6320309.
1218 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1219 if (debug_logging_enabled) {
1220 ResourceMark rm(jt);
1221 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1222 jt->name(), external_name(), init_thread_name());
1223 }
1224 wait = true;
1225 jt->set_class_to_be_initialized(this);
1226 ol.wait_uninterruptibly(jt);
1227 jt->set_class_to_be_initialized(nullptr);
1228 }
1229
1230 // Step 3
1231 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1232 if (debug_logging_enabled) {
1233 ResourceMark rm(jt);
1234 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1235 jt->name(), external_name());
1236 }
1237 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1238 return;
1239 }
1240
1241 // Step 4
1242 if (is_initialized()) {
1243 if (debug_logging_enabled) {
1244 ResourceMark rm(jt);
1245 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1246 jt->name(), external_name());
1247 }
1248 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1249 return;
1250 }
1251
1252 // Step 5
1253 if (is_in_error_state()) {
1254 if (debug_logging_enabled) {
1255 ResourceMark rm(jt);
1256 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1257 jt->name(), external_name());
1258 }
1259
1260 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1261 ResourceMark rm(THREAD);
1262 Handle cause(THREAD, get_initialization_error(THREAD));
1263
1264 stringStream ss;
1265 ss.print("Could not initialize class %s", external_name());
1266 if (cause.is_null()) {
1267 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1268 } else {
1269 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1270 ss.as_string(), cause);
1271 }
1272 } else {
1273
1274 // Step 6
1275 set_init_state(being_initialized);
1276 set_init_thread(jt);
1277 if (debug_logging_enabled) {
1278 ResourceMark rm(jt);
1279 log_debug(class, init)("Thread \"%s\" is initializing %s",
1280 jt->name(), external_name());
1281 }
1282 }
1283 }
1284
1285 // Step 7
1286 // Next, if C is a class rather than an interface, initialize it's super class and super
1287 // interfaces.
1288 if (!is_interface()) {
1289 Klass* super_klass = super();
1290 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1291 super_klass->initialize(THREAD);
1292 }
1293 // If C implements any interface that declares a non-static, concrete method,
1294 // the initialization of C triggers initialization of its super interfaces.
1295 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1296 // having a superinterface that declares, non-static, concrete methods
1297 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1298 initialize_super_interfaces(THREAD);
1299 }
1300
1301 // If any exceptions, complete abruptly, throwing the same exception as above.
1302 if (HAS_PENDING_EXCEPTION) {
1303 Handle e(THREAD, PENDING_EXCEPTION);
1304 CLEAR_PENDING_EXCEPTION;
1305 {
1306 EXCEPTION_MARK;
1307 add_initialization_error(THREAD, e);
1308 // Locks object, set state, and notify all waiting threads
1309 set_initialization_state_and_notify(initialization_error, THREAD);
1310 CLEAR_PENDING_EXCEPTION;
1311 }
1312 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1313 THROW_OOP(e());
1314 }
1315 }
1316
1317
1318 // Step 8
1319 {
1320 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1321 if (class_initializer() != nullptr) {
1322 // Timer includes any side effects of class initialization (resolution,
1323 // etc), but not recursive entry into call_class_initializer().
1324 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1325 ClassLoader::perf_class_init_selftime(),
1326 ClassLoader::perf_classes_inited(),
1327 jt->get_thread_stat()->perf_recursion_counts_addr(),
1328 jt->get_thread_stat()->perf_timers_addr(),
1329 PerfClassTraceTime::CLASS_CLINIT);
1330 call_class_initializer(THREAD);
1331 } else {
1332 // The elapsed time is so small it's not worth counting.
1333 if (UsePerfData) {
1334 ClassLoader::perf_classes_inited()->inc();
1335 }
1336 call_class_initializer(THREAD);
1337 }
1338 }
1339
1340 // Step 9
1341 if (!HAS_PENDING_EXCEPTION) {
1342 set_initialization_state_and_notify(fully_initialized, CHECK);
1343 debug_only(vtable().verify(tty, true);)
1344 CompilationPolicy::replay_training_at_init(this, THREAD);
1345 }
1346 else {
1347 // Step 10 and 11
1348 Handle e(THREAD, PENDING_EXCEPTION);
1349 CLEAR_PENDING_EXCEPTION;
1350 // JVMTI has already reported the pending exception
1351 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1352 JvmtiExport::clear_detected_exception(jt);
1353 {
1354 EXCEPTION_MARK;
1355 add_initialization_error(THREAD, e);
1356 set_initialization_state_and_notify(initialization_error, THREAD);
1357 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1358 // JVMTI has already reported the pending exception
1359 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1360 JvmtiExport::clear_detected_exception(jt);
1361 }
1362 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1363 if (e->is_a(vmClasses::Error_klass())) {
1364 THROW_OOP(e());
1365 } else {
1366 JavaCallArguments args(e);
1367 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1368 vmSymbols::throwable_void_signature(),
1369 &args);
1370 }
1371 }
1372 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1373 }
1374
1375 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1376 Handle h_init_lock(THREAD, init_lock());
1377 if (h_init_lock() != nullptr) {
1378 ObjectLocker ol(h_init_lock, THREAD);
1379 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1380 set_init_state(state);
1381 fence_and_clear_init_lock();
1382 ol.notify_all(CHECK);
1383 } else {
1384 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1385 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1386 set_init_state(state);
1387 }
1388 }
1389
1390 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1391 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1392 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1393 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1394
1395 DeoptimizationScope deopt_scope;
1396 {
1397 MutexLocker ml(current, Compile_lock);
1398
1399 set_init_state(InstanceKlass::loaded);
1400 // make sure init_state store is already done.
1401 // The compiler reads the hierarchy outside of the Compile_lock.
1402 // Access ordering is used to add to hierarchy.
1403
1404 // Link into hierarchy.
1405 append_to_sibling_list(); // add to superklass/sibling list
1406 process_interfaces(); // handle all "implements" declarations
1407
1408 // Now mark all code that depended on old class hierarchy.
1409 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1410 if (Universe::is_fully_initialized()) {
1411 CodeCache::mark_dependents_on(&deopt_scope, this);
1412 }
1413 }
1414 // Perform the deopt handshake outside Compile_lock.
1415 deopt_scope.deoptimize_marked();
1416 }
1417
1418
1419 InstanceKlass* InstanceKlass::implementor() const {
1420 InstanceKlass* volatile* ik = adr_implementor();
1421 if (ik == nullptr) {
1422 return nullptr;
1423 } else {
1424 // This load races with inserts, and therefore needs acquire.
1425 InstanceKlass* ikls = Atomic::load_acquire(ik);
1426 if (ikls != nullptr && !ikls->is_loader_alive()) {
1427 return nullptr; // don't return unloaded class
1428 } else {
1429 return ikls;
1430 }
1431 }
1432 }
1433
1434
1435 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1436 assert_locked_or_safepoint(Compile_lock);
1437 assert(is_interface(), "not interface");
1438 InstanceKlass* volatile* addr = adr_implementor();
1439 assert(addr != nullptr, "null addr");
1440 if (addr != nullptr) {
1441 Atomic::release_store(addr, ik);
1442 }
1443 }
1444
1445 int InstanceKlass::nof_implementors() const {
1446 InstanceKlass* ik = implementor();
1447 if (ik == nullptr) {
1448 return 0;
1449 } else if (ik != this) {
1450 return 1;
1451 } else {
1452 return 2;
1453 }
1454 }
1455
1456 // The embedded _implementor field can only record one implementor.
1457 // When there are more than one implementors, the _implementor field
1458 // is set to the interface Klass* itself. Following are the possible
1459 // values for the _implementor field:
1460 // null - no implementor
1461 // implementor Klass* - one implementor
1462 // self - more than one implementor
1463 //
1464 // The _implementor field only exists for interfaces.
1465 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1466 if (Universe::is_fully_initialized()) {
1467 assert_lock_strong(Compile_lock);
1468 }
1469 assert(is_interface(), "not interface");
1470 // Filter out my subinterfaces.
1471 // (Note: Interfaces are never on the subklass list.)
1472 if (ik->is_interface()) return;
1473
1474 // Filter out subclasses whose supers already implement me.
1475 // (Note: CHA must walk subclasses of direct implementors
1476 // in order to locate indirect implementors.)
1477 InstanceKlass* super_ik = ik->java_super();
1478 if (super_ik != nullptr && super_ik->implements_interface(this))
1479 // We only need to check one immediate superclass, since the
1480 // implements_interface query looks at transitive_interfaces.
1481 // Any supers of the super have the same (or fewer) transitive_interfaces.
1482 return;
1483
1484 InstanceKlass* iklass = implementor();
1485 if (iklass == nullptr) {
1486 set_implementor(ik);
1487 } else if (iklass != this && iklass != ik) {
1488 // There is already an implementor. Use itself as an indicator of
1489 // more than one implementors.
1490 set_implementor(this);
1491 }
1492
1493 // The implementor also implements the transitive_interfaces
1494 for (int index = 0; index < local_interfaces()->length(); index++) {
1495 local_interfaces()->at(index)->add_implementor(ik);
1496 }
1497 }
1498
1499 void InstanceKlass::init_implementor() {
1500 if (is_interface()) {
1501 set_implementor(nullptr);
1502 }
1503 }
1504
1505
1506 void InstanceKlass::process_interfaces() {
1507 // link this class into the implementors list of every interface it implements
1508 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1509 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1510 InstanceKlass* interf = local_interfaces()->at(i);
1511 assert(interf->is_interface(), "expected interface");
1512 interf->add_implementor(this);
1513 }
1514 }
1515
1516 bool InstanceKlass::can_be_primary_super_slow() const {
1517 if (is_interface())
1518 return false;
1519 else
1520 return Klass::can_be_primary_super_slow();
1521 }
1522
1523 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1524 Array<InstanceKlass*>* transitive_interfaces) {
1525 // The secondaries are the implemented interfaces.
1526 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1527 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1528 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1529 int num_secondaries = num_extra_slots + interfaces->length();
1530 if (num_secondaries == 0) {
1531 // Must share this for correct bootstrapping!
1532 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1533 return nullptr;
1534 } else if (num_extra_slots == 0) {
1535 // The secondary super list is exactly the same as the transitive interfaces, so
1536 // let's use it instead of making a copy.
1537 // Redefine classes has to be careful not to delete this!
1538 if (!UseSecondarySupersTable) {
1539 set_secondary_supers(interfaces);
1540 return nullptr;
1541 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1542 // We will reuse the transitive interfaces list if we're certain
1543 // it's in hash order.
1544 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1545 set_secondary_supers(interfaces, bitmap);
1546 return nullptr;
1547 }
1548 // ... fall through if that didn't work.
1549 }
1550 // Copy transitive interfaces to a temporary growable array to be constructed
1551 // into the secondary super list with extra slots.
1552 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1553 for (int i = 0; i < interfaces->length(); i++) {
1554 secondaries->push(interfaces->at(i));
1555 }
1556 return secondaries;
1557 }
1558
1559 bool InstanceKlass::implements_interface(Klass* k) const {
1560 if (this == k) return true;
1561 assert(k->is_interface(), "should be an interface class");
1562 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1563 if (transitive_interfaces()->at(i) == k) {
1564 return true;
1565 }
1566 }
1567 return false;
1568 }
1569
1570 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1571 // Verify direct super interface
1572 if (this == k) return true;
1573 assert(k->is_interface(), "should be an interface class");
1574 for (int i = 0; i < local_interfaces()->length(); i++) {
1575 if (local_interfaces()->at(i) == k) {
1576 return true;
1577 }
1578 }
1579 return false;
1580 }
1581
1582 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1583 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1584 size_t size = objArrayOopDesc::object_size(length);
1585 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1586 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1587 /* do_zero */ true, CHECK_NULL);
1588 return o;
1589 }
1590
1591 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1592 if (TraceFinalizerRegistration) {
1593 tty->print("Registered ");
1594 i->print_value_on(tty);
1595 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1596 }
1597 instanceHandle h_i(THREAD, i);
1598 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1599 JavaValue result(T_VOID);
1600 JavaCallArguments args(h_i);
1601 methodHandle mh(THREAD, Universe::finalizer_register_method());
1602 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1603 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1604 return h_i();
1605 }
1606
1607 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1608 assert(!is_abstract() && !is_interface(), "Should not create this object");
1609 size_t size = size_helper(); // Query before forming handle.
1610 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1611 }
1612
1613 instanceOop InstanceKlass::allocate_instance(oop java_class,
1614 const char* who,
1615 TRAPS) {
1616 Klass* k = java_lang_Class::as_Klass(java_class);
1617 if (k == nullptr) {
1618 ResourceMark rm(THREAD);
1619 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1620 }
1621 InstanceKlass* ik = cast(k);
1622 ik->check_valid_for_instantiation(false, CHECK_NULL);
1623 ik->initialize(CHECK_NULL);
1624 return ik->allocate_instance(THREAD);
1625 }
1626
1627 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1628 return instanceHandle(THREAD, allocate_instance(THREAD));
1629 }
1630
1631 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1632 if (is_interface() || is_abstract()) {
1633 ResourceMark rm(THREAD);
1634 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1635 : vmSymbols::java_lang_InstantiationException(), external_name());
1636 }
1637 if (this == vmClasses::Class_klass()) {
1638 ResourceMark rm(THREAD);
1639 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1640 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1641 }
1642 }
1643
1644 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1645 // Need load-acquire for lock-free read
1646 if (array_klasses_acquire() == nullptr) {
1647
1648 // Recursively lock array allocation
1649 RecursiveLocker rl(MultiArray_lock, THREAD);
1650
1651 // Check if another thread created the array klass while we were waiting for the lock.
1652 if (array_klasses() == nullptr) {
1653 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1654 // use 'release' to pair with lock-free load
1655 release_set_array_klasses(k);
1656 }
1657 }
1658
1659 // array_klasses() will always be set at this point
1660 ObjArrayKlass* ak = array_klasses();
1661 assert(ak != nullptr, "should be set");
1662 return ak->array_klass(n, THREAD);
1663 }
1664
1665 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1666 // Need load-acquire for lock-free read
1667 ObjArrayKlass* oak = array_klasses_acquire();
1668 if (oak == nullptr) {
1669 return nullptr;
1670 } else {
1671 return oak->array_klass_or_null(n);
1672 }
1673 }
1674
1675 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1676 return array_klass(1, THREAD);
1677 }
1678
1679 ArrayKlass* InstanceKlass::array_klass_or_null() {
1680 return array_klass_or_null(1);
1681 }
1682
1683 Method* InstanceKlass::class_initializer() const {
1684 Method* clinit = find_method(
1685 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1686 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1687 return clinit;
1688 }
1689 return nullptr;
1690 }
1691
1692 void InstanceKlass::call_class_initializer(TRAPS) {
1693 if (ReplayCompiles &&
1694 (ReplaySuppressInitializers == 1 ||
1695 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1696 // Hide the existence of the initializer for the purpose of replaying the compile
1697 return;
1698 }
1699
1700 #if INCLUDE_CDS
1701 // This is needed to ensure the consistency of the archived heap objects.
1702 if (has_archived_enum_objs()) {
1703 assert(is_shared(), "must be");
1704 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1705 if (initialized) {
1706 return;
1707 }
1708 } else if (has_preinitialized_mirror() && CDSConfig::is_loading_heap()) {
1709 log_class_init(THREAD, this);
1710 return;
1711 }
1712 #endif
1713
1714 methodHandle h_method(THREAD, class_initializer());
1715 assert(!is_initialized(), "we cannot initialize twice");
1716 int init_id = log_class_init(THREAD, this);
1717 if (h_method() != nullptr) {
1718 JavaCallArguments args; // No arguments
1719 JavaValue result(T_VOID);
1720 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1721 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1722
1723 elapsedTimer timer;
1724 {
1725 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1726 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1727
1728 timer.start();
1729 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1730 timer.stop();
1731 }
1732
1733 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1734
1735 jlong bc_executed = (bc_end - bc_start);
1736 if (UsePerfData && outer == nullptr) { // outermost clinit
1737 THREAD->inc_clinit_bc_counter_value(bc_executed);
1738 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1739 }
1740
1741 THREAD->set_class_being_initialized(outer);
1742
1743 LogStreamHandle(Debug, init) log;
1744 if (log.is_enabled()) {
1745 ResourceMark rm(THREAD);
1746 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1747 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1748 if (CountBytecodes || CountBytecodesPerThread) {
1749 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1750 }
1751 name()->print_value_on(&log);
1752 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1753 p2i(THREAD), THREAD->name(), p2i(this));
1754 }
1755 }
1756 LogTarget(Info, class, init) lt;
1757 if (lt.is_enabled()) {
1758 ResourceMark rm(THREAD);
1759 LogStream ls(lt);
1760 ls.print("%d Initialized ", init_id);
1761 name()->print_value_on(&ls);
1762 ls.print_cr("%s (" PTR_FORMAT ")", h_method() == nullptr ? "(no method)" : "", p2i(this));
1763 }
1764 }
1765
1766 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1767 InterpreterOopMap* entry_for) {
1768 // Lazily create the _oop_map_cache at first request.
1769 // Load_acquire is needed to safely get instance published with CAS by another thread.
1770 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1771 if (oop_map_cache == nullptr) {
1772 // Try to install new instance atomically.
1773 oop_map_cache = new OopMapCache();
1774 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1775 if (other != nullptr) {
1776 // Someone else managed to install before us, ditch local copy and use the existing one.
1777 delete oop_map_cache;
1778 oop_map_cache = other;
1779 }
1780 }
1781 // _oop_map_cache is constant after init; lookup below does its own locking.
1782 oop_map_cache->lookup(method, bci, entry_for);
1783 }
1784
1785 bool InstanceKlass::contains_field_offset(int offset) {
1786 fieldDescriptor fd;
1787 return find_field_from_offset(offset, false, &fd);
1788 }
1789
1790 FieldInfo InstanceKlass::field(int index) const {
1791 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1792 if (fs.index() == index) {
1793 return fs.to_FieldInfo();
1794 }
1795 }
1796 fatal("Field not found");
1797 return FieldInfo();
1798 }
1799
1800 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1801 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1802 Symbol* f_name = fs.name();
1803 Symbol* f_sig = fs.signature();
1804 if (f_name == name && f_sig == sig) {
1805 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1806 return true;
1807 }
1808 }
1809 return false;
1810 }
1811
1812
1813 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1814 const int n = local_interfaces()->length();
1815 for (int i = 0; i < n; i++) {
1816 Klass* intf1 = local_interfaces()->at(i);
1817 assert(intf1->is_interface(), "just checking type");
1818 // search for field in current interface
1819 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1820 assert(fd->is_static(), "interface field must be static");
1821 return intf1;
1822 }
1823 // search for field in direct superinterfaces
1824 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1825 if (intf2 != nullptr) return intf2;
1826 }
1827 // otherwise field lookup fails
1828 return nullptr;
1829 }
1830
1831
1832 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1833 // search order according to newest JVM spec (5.4.3.2, p.167).
1834 // 1) search for field in current klass
1835 if (find_local_field(name, sig, fd)) {
1836 return const_cast<InstanceKlass*>(this);
1837 }
1838 // 2) search for field recursively in direct superinterfaces
1839 { Klass* intf = find_interface_field(name, sig, fd);
1840 if (intf != nullptr) return intf;
1841 }
1842 // 3) apply field lookup recursively if superclass exists
1843 { Klass* supr = super();
1844 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1845 }
1846 // 4) otherwise field lookup fails
1847 return nullptr;
1848 }
1849
1850
1851 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1852 // search order according to newest JVM spec (5.4.3.2, p.167).
1853 // 1) search for field in current klass
1854 if (find_local_field(name, sig, fd)) {
1855 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1856 }
1857 // 2) search for field recursively in direct superinterfaces
1858 if (is_static) {
1859 Klass* intf = find_interface_field(name, sig, fd);
1860 if (intf != nullptr) return intf;
1861 }
1862 // 3) apply field lookup recursively if superclass exists
1863 { Klass* supr = super();
1864 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1865 }
1866 // 4) otherwise field lookup fails
1867 return nullptr;
1868 }
1869
1870
1871 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1872 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1873 if (fs.offset() == offset) {
1874 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1875 if (fd->is_static() == is_static) return true;
1876 }
1877 }
1878 return false;
1879 }
1880
1881
1882 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1883 Klass* klass = const_cast<InstanceKlass*>(this);
1884 while (klass != nullptr) {
1885 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1886 return true;
1887 }
1888 klass = klass->super();
1889 }
1890 return false;
1891 }
1892
1893
1894 void InstanceKlass::methods_do(void f(Method* method)) {
1895 // Methods aren't stable until they are loaded. This can be read outside
1896 // a lock through the ClassLoaderData for profiling
1897 // Redefined scratch classes are on the list and need to be cleaned
1898 if (!is_loaded() && !is_scratch_class()) {
1899 return;
1900 }
1901
1902 int len = methods()->length();
1903 for (int index = 0; index < len; index++) {
1904 Method* m = methods()->at(index);
1905 assert(m->is_method(), "must be method");
1906 f(m);
1907 }
1908 }
1909
1910
1911 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1912 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1913 if (fs.access_flags().is_static()) {
1914 fieldDescriptor& fd = fs.field_descriptor();
1915 cl->do_field(&fd);
1916 }
1917 }
1918 }
1919
1920
1921 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1922 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1923 if (fs.access_flags().is_static()) {
1924 fieldDescriptor& fd = fs.field_descriptor();
1925 f(&fd, mirror, CHECK);
1926 }
1927 }
1928 }
1929
1930 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1931 InstanceKlass* super = superklass();
1932 if (super != nullptr) {
1933 super->do_nonstatic_fields(cl);
1934 }
1935 fieldDescriptor fd;
1936 int length = java_fields_count();
1937 for (int i = 0; i < length; i += 1) {
1938 fd.reinitialize(this, i);
1939 if (!fd.is_static()) {
1940 cl->do_field(&fd);
1941 }
1942 }
1943 }
1944
1945 // first in Pair is offset, second is index.
1946 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1947 return a->first - b->first;
1948 }
1949
1950 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1951 InstanceKlass* super = superklass();
1952 if (super != nullptr) {
1953 super->print_nonstatic_fields(cl);
1954 }
1955 ResourceMark rm;
1956 fieldDescriptor fd;
1957 // In DebugInfo nonstatic fields are sorted by offset.
1958 GrowableArray<Pair<int,int> > fields_sorted;
1959 int i = 0;
1960 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1961 if (!fs.access_flags().is_static()) {
1962 fd = fs.field_descriptor();
1963 Pair<int,int> f(fs.offset(), fs.index());
1964 fields_sorted.push(f);
1965 i++;
1966 }
1967 }
1968 if (i > 0) {
1969 int length = i;
1970 assert(length == fields_sorted.length(), "duh");
1971 fields_sorted.sort(compare_fields_by_offset);
1972 for (int i = 0; i < length; i++) {
1973 fd.reinitialize(this, fields_sorted.at(i).second);
1974 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1975 cl->do_field(&fd);
1976 }
1977 }
1978 }
1979
1980 #ifdef ASSERT
1981 static int linear_search(const Array<Method*>* methods,
1982 const Symbol* name,
1983 const Symbol* signature) {
1984 const int len = methods->length();
1985 for (int index = 0; index < len; index++) {
1986 const Method* const m = methods->at(index);
1987 assert(m->is_method(), "must be method");
1988 if (m->signature() == signature && m->name() == name) {
1989 return index;
1990 }
1991 }
1992 return -1;
1993 }
1994 #endif
1995
1996 bool InstanceKlass::_disable_method_binary_search = false;
1997
1998 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1999 int len = methods->length();
2000 int l = 0;
2001 int h = len - 1;
2002 while (l <= h) {
2003 Method* m = methods->at(l);
2004 if (m->name() == name) {
2005 return l;
2006 }
2007 l++;
2008 }
2009 return -1;
2010 }
2011
2012 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2013 if (_disable_method_binary_search) {
2014 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2015 // At the final stage of dynamic dumping, the methods array may not be sorted
2016 // by ascending addresses of their names, so we can't use binary search anymore.
2017 // However, methods with the same name are still laid out consecutively inside the
2018 // methods array, so let's look for the first one that matches.
2019 return linear_search(methods, name);
2020 }
2021
2022 int len = methods->length();
2023 int l = 0;
2024 int h = len - 1;
2025
2026 // methods are sorted by ascending addresses of their names, so do binary search
2027 while (l <= h) {
2028 int mid = (l + h) >> 1;
2029 Method* m = methods->at(mid);
2030 assert(m->is_method(), "must be method");
2031 int res = m->name()->fast_compare(name);
2032 if (res == 0) {
2033 return mid;
2034 } else if (res < 0) {
2035 l = mid + 1;
2036 } else {
2037 h = mid - 1;
2038 }
2039 }
2040 return -1;
2041 }
2042
2043 // find_method looks up the name/signature in the local methods array
2044 Method* InstanceKlass::find_method(const Symbol* name,
2045 const Symbol* signature) const {
2046 return find_method_impl(name, signature,
2047 OverpassLookupMode::find,
2048 StaticLookupMode::find,
2049 PrivateLookupMode::find);
2050 }
2051
2052 Method* InstanceKlass::find_method_impl(const Symbol* name,
2053 const Symbol* signature,
2054 OverpassLookupMode overpass_mode,
2055 StaticLookupMode static_mode,
2056 PrivateLookupMode private_mode) const {
2057 return InstanceKlass::find_method_impl(methods(),
2058 name,
2059 signature,
2060 overpass_mode,
2061 static_mode,
2062 private_mode);
2063 }
2064
2065 // find_instance_method looks up the name/signature in the local methods array
2066 // and skips over static methods
2067 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2068 const Symbol* name,
2069 const Symbol* signature,
2070 PrivateLookupMode private_mode) {
2071 Method* const meth = InstanceKlass::find_method_impl(methods,
2072 name,
2073 signature,
2074 OverpassLookupMode::find,
2075 StaticLookupMode::skip,
2076 private_mode);
2077 assert(((meth == nullptr) || !meth->is_static()),
2078 "find_instance_method should have skipped statics");
2079 return meth;
2080 }
2081
2082 // find_instance_method looks up the name/signature in the local methods array
2083 // and skips over static methods
2084 Method* InstanceKlass::find_instance_method(const Symbol* name,
2085 const Symbol* signature,
2086 PrivateLookupMode private_mode) const {
2087 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2088 }
2089
2090 // Find looks up the name/signature in the local methods array
2091 // and filters on the overpass, static and private flags
2092 // This returns the first one found
2093 // note that the local methods array can have up to one overpass, one static
2094 // and one instance (private or not) with the same name/signature
2095 Method* InstanceKlass::find_local_method(const Symbol* name,
2096 const Symbol* signature,
2097 OverpassLookupMode overpass_mode,
2098 StaticLookupMode static_mode,
2099 PrivateLookupMode private_mode) const {
2100 return InstanceKlass::find_method_impl(methods(),
2101 name,
2102 signature,
2103 overpass_mode,
2104 static_mode,
2105 private_mode);
2106 }
2107
2108 // Find looks up the name/signature in the local methods array
2109 // and filters on the overpass, static and private flags
2110 // This returns the first one found
2111 // note that the local methods array can have up to one overpass, one static
2112 // and one instance (private or not) with the same name/signature
2113 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2114 const Symbol* name,
2115 const Symbol* signature,
2116 OverpassLookupMode overpass_mode,
2117 StaticLookupMode static_mode,
2118 PrivateLookupMode private_mode) {
2119 return InstanceKlass::find_method_impl(methods,
2120 name,
2121 signature,
2122 overpass_mode,
2123 static_mode,
2124 private_mode);
2125 }
2126
2127 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2128 const Symbol* name,
2129 const Symbol* signature) {
2130 return InstanceKlass::find_method_impl(methods,
2131 name,
2132 signature,
2133 OverpassLookupMode::find,
2134 StaticLookupMode::find,
2135 PrivateLookupMode::find);
2136 }
2137
2138 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2139 const Symbol* name,
2140 const Symbol* signature,
2141 OverpassLookupMode overpass_mode,
2142 StaticLookupMode static_mode,
2143 PrivateLookupMode private_mode) {
2144 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2145 return hit >= 0 ? methods->at(hit): nullptr;
2146 }
2147
2148 // true if method matches signature and conforms to skipping_X conditions.
2149 static bool method_matches(const Method* m,
2150 const Symbol* signature,
2151 bool skipping_overpass,
2152 bool skipping_static,
2153 bool skipping_private) {
2154 return ((m->signature() == signature) &&
2155 (!skipping_overpass || !m->is_overpass()) &&
2156 (!skipping_static || !m->is_static()) &&
2157 (!skipping_private || !m->is_private()));
2158 }
2159
2160 // Used directly for default_methods to find the index into the
2161 // default_vtable_indices, and indirectly by find_method
2162 // find_method_index looks in the local methods array to return the index
2163 // of the matching name/signature. If, overpass methods are being ignored,
2164 // the search continues to find a potential non-overpass match. This capability
2165 // is important during method resolution to prefer a static method, for example,
2166 // over an overpass method.
2167 // There is the possibility in any _method's array to have the same name/signature
2168 // for a static method, an overpass method and a local instance method
2169 // To correctly catch a given method, the search criteria may need
2170 // to explicitly skip the other two. For local instance methods, it
2171 // is often necessary to skip private methods
2172 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2173 const Symbol* name,
2174 const Symbol* signature,
2175 OverpassLookupMode overpass_mode,
2176 StaticLookupMode static_mode,
2177 PrivateLookupMode private_mode) {
2178 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2179 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2180 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2181 const int hit = quick_search(methods, name);
2182 if (hit != -1) {
2183 const Method* const m = methods->at(hit);
2184
2185 // Do linear search to find matching signature. First, quick check
2186 // for common case, ignoring overpasses if requested.
2187 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2188 return hit;
2189 }
2190
2191 // search downwards through overloaded methods
2192 int i;
2193 for (i = hit - 1; i >= 0; --i) {
2194 const Method* const m = methods->at(i);
2195 assert(m->is_method(), "must be method");
2196 if (m->name() != name) {
2197 break;
2198 }
2199 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2200 return i;
2201 }
2202 }
2203 // search upwards
2204 for (i = hit + 1; i < methods->length(); ++i) {
2205 const Method* const m = methods->at(i);
2206 assert(m->is_method(), "must be method");
2207 if (m->name() != name) {
2208 break;
2209 }
2210 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2211 return i;
2212 }
2213 }
2214 // not found
2215 #ifdef ASSERT
2216 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2217 linear_search(methods, name, signature);
2218 assert(-1 == index, "binary search should have found entry %d", index);
2219 #endif
2220 }
2221 return -1;
2222 }
2223
2224 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2225 return find_method_by_name(methods(), name, end);
2226 }
2227
2228 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2229 const Symbol* name,
2230 int* end_ptr) {
2231 assert(end_ptr != nullptr, "just checking");
2232 int start = quick_search(methods, name);
2233 int end = start + 1;
2234 if (start != -1) {
2235 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2236 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2237 *end_ptr = end;
2238 return start;
2239 }
2240 return -1;
2241 }
2242
2243 // uncached_lookup_method searches both the local class methods array and all
2244 // superclasses methods arrays, skipping any overpass methods in superclasses,
2245 // and possibly skipping private methods.
2246 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2247 const Symbol* signature,
2248 OverpassLookupMode overpass_mode,
2249 PrivateLookupMode private_mode) const {
2250 OverpassLookupMode overpass_local_mode = overpass_mode;
2251 const Klass* klass = this;
2252 while (klass != nullptr) {
2253 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2254 signature,
2255 overpass_local_mode,
2256 StaticLookupMode::find,
2257 private_mode);
2258 if (method != nullptr) {
2259 return method;
2260 }
2261 klass = klass->super();
2262 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2263 }
2264 return nullptr;
2265 }
2266
2267 #ifdef ASSERT
2268 // search through class hierarchy and return true if this class or
2269 // one of the superclasses was redefined
2270 bool InstanceKlass::has_redefined_this_or_super() const {
2271 const Klass* klass = this;
2272 while (klass != nullptr) {
2273 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2274 return true;
2275 }
2276 klass = klass->super();
2277 }
2278 return false;
2279 }
2280 #endif
2281
2282 // lookup a method in the default methods list then in all transitive interfaces
2283 // Do NOT return private or static methods
2284 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2285 Symbol* signature) const {
2286 Method* m = nullptr;
2287 if (default_methods() != nullptr) {
2288 m = find_method(default_methods(), name, signature);
2289 }
2290 // Look up interfaces
2291 if (m == nullptr) {
2292 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2293 }
2294 return m;
2295 }
2296
2297 // lookup a method in all the interfaces that this class implements
2298 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2299 // They should only be found in the initial InterfaceMethodRef
2300 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2301 Symbol* signature,
2302 DefaultsLookupMode defaults_mode) const {
2303 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2304 int num_ifs = all_ifs->length();
2305 InstanceKlass *ik = nullptr;
2306 for (int i = 0; i < num_ifs; i++) {
2307 ik = all_ifs->at(i);
2308 Method* m = ik->lookup_method(name, signature);
2309 if (m != nullptr && m->is_public() && !m->is_static() &&
2310 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2311 return m;
2312 }
2313 }
2314 return nullptr;
2315 }
2316
2317 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2318 :_st(st), _verbose(verbose) {
2319 ResourceMark rm;
2320 _st->print("%-18s ", "KlassAddr");
2321 _st->print("%-4s ", "Size");
2322 _st->print("%-20s ", "State");
2323 _st->print("%-7s ", "Flags");
2324 _st->print("%-5s ", "ClassName");
2325 _st->cr();
2326 }
2327
2328 void PrintClassClosure::do_klass(Klass* k) {
2329 ResourceMark rm;
2330 // klass pointer
2331 _st->print(PTR_FORMAT " ", p2i(k));
2332 // klass size
2333 _st->print("%4d ", k->size());
2334 // initialization state
2335 if (k->is_instance_klass()) {
2336 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2337 } else {
2338 _st->print("%-20s ","");
2339 }
2340 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2341 char buf[10];
2342 int i = 0;
2343 if (k->has_finalizer()) buf[i++] = 'F';
2344 if (k->is_instance_klass()) {
2345 InstanceKlass* ik = InstanceKlass::cast(k);
2346 if (ik->has_final_method()) buf[i++] = 'f';
2347 if (ik->is_rewritten()) buf[i++] = 'W';
2348 if (ik->is_contended()) buf[i++] = 'C';
2349 if (ik->has_been_redefined()) buf[i++] = 'R';
2350 if (ik->is_shared()) buf[i++] = 'S';
2351 }
2352 buf[i++] = '\0';
2353 _st->print("%-7s ", buf);
2354 // klass name
2355 _st->print("%-5s ", k->external_name());
2356 // end
2357 _st->cr();
2358 if (_verbose) {
2359 k->print_on(_st);
2360 }
2361 }
2362
2363 /* jni_id_for for jfieldIds only */
2364 JNIid* InstanceKlass::jni_id_for(int offset) {
2365 MutexLocker ml(JfieldIdCreation_lock);
2366 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2367 if (probe == nullptr) {
2368 // Allocate new static field identifier
2369 probe = new JNIid(this, offset, jni_ids());
2370 set_jni_ids(probe);
2371 }
2372 return probe;
2373 }
2374
2375 u2 InstanceKlass::enclosing_method_data(int offset) const {
2376 const Array<jushort>* const inner_class_list = inner_classes();
2377 if (inner_class_list == nullptr) {
2378 return 0;
2379 }
2380 const int length = inner_class_list->length();
2381 if (length % inner_class_next_offset == 0) {
2382 return 0;
2383 }
2384 const int index = length - enclosing_method_attribute_size;
2385 assert(offset < enclosing_method_attribute_size, "invalid offset");
2386 return inner_class_list->at(index + offset);
2387 }
2388
2389 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2390 u2 method_index) {
2391 Array<jushort>* inner_class_list = inner_classes();
2392 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2393 int length = inner_class_list->length();
2394 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2395 int index = length - enclosing_method_attribute_size;
2396 inner_class_list->at_put(
2397 index + enclosing_method_class_index_offset, class_index);
2398 inner_class_list->at_put(
2399 index + enclosing_method_method_index_offset, method_index);
2400 }
2401 }
2402
2403 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2404 if (method->is_old() && !method->is_obsolete()) {
2405 // If the method passed in is old (but not obsolete), use the current version.
2406 method = method_with_idnum((int)idnum);
2407 assert(method != nullptr, "old and but not obsolete, so should exist");
2408 }
2409 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2410 Atomic::release_store(&jmeths[idnum + 1], new_id);
2411 return new_id;
2412 }
2413
2414 // Lookup or create a jmethodID.
2415 // This code is called by the VMThread and JavaThreads so the
2416 // locking has to be done very carefully to avoid deadlocks
2417 // and/or other cache consistency problems.
2418 //
2419 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2420 Method* method = method_h();
2421 int idnum = method->method_idnum();
2422 jmethodID* jmeths = methods_jmethod_ids_acquire();
2423
2424 // We use a double-check locking idiom here because this cache is
2425 // performance sensitive. In the normal system, this cache only
2426 // transitions from null to non-null which is safe because we use
2427 // release_set_methods_jmethod_ids() to advertise the new cache.
2428 // A partially constructed cache should never be seen by a racing
2429 // thread. We also use release_store() to save a new jmethodID
2430 // in the cache so a partially constructed jmethodID should never be
2431 // seen either. Cache reads of existing jmethodIDs proceed without a
2432 // lock, but cache writes of a new jmethodID requires uniqueness and
2433 // creation of the cache itself requires no leaks so a lock is
2434 // acquired in those two cases.
2435 //
2436 // If the RedefineClasses() API has been used, then this cache grows
2437 // in the redefinition safepoint.
2438
2439 if (jmeths == nullptr) {
2440 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2441 jmeths = methods_jmethod_ids_acquire();
2442 // Still null?
2443 if (jmeths == nullptr) {
2444 size_t size = idnum_allocated_count();
2445 assert(size > (size_t)idnum, "should already have space");
2446 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2447 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2448 // cache size is stored in element[0], other elements offset by one
2449 jmeths[0] = (jmethodID)size;
2450 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2451
2452 // publish jmeths
2453 release_set_methods_jmethod_ids(jmeths);
2454 return new_id;
2455 }
2456 }
2457
2458 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2459 if (id == nullptr) {
2460 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2461 id = jmeths[idnum + 1];
2462 // Still null?
2463 if (id == nullptr) {
2464 return update_jmethod_id(jmeths, method, idnum);
2465 }
2466 }
2467 return id;
2468 }
2469
2470 void InstanceKlass::update_methods_jmethod_cache() {
2471 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2472 jmethodID* cache = _methods_jmethod_ids;
2473 if (cache != nullptr) {
2474 size_t size = idnum_allocated_count();
2475 size_t old_size = (size_t)cache[0];
2476 if (old_size < size + 1) {
2477 // Allocate a larger one and copy entries to the new one.
2478 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2479 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2480 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2481 // The cache size is stored in element[0]; the other elements are offset by one.
2482 new_cache[0] = (jmethodID)size;
2483
2484 for (int i = 1; i <= (int)old_size; i++) {
2485 new_cache[i] = cache[i];
2486 }
2487 _methods_jmethod_ids = new_cache;
2488 FREE_C_HEAP_ARRAY(jmethodID, cache);
2489 }
2490 }
2491 }
2492
2493 // Figure out how many jmethodIDs haven't been allocated, and make
2494 // sure space for them is pre-allocated. This makes getting all
2495 // method ids much, much faster with classes with more than 8
2496 // methods, and has a *substantial* effect on performance with jvmti
2497 // code that loads all jmethodIDs for all classes.
2498 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2499 int new_jmeths = 0;
2500 int length = methods()->length();
2501 for (int index = start_offset; index < length; index++) {
2502 Method* m = methods()->at(index);
2503 jmethodID id = m->find_jmethod_id_or_null();
2504 if (id == nullptr) {
2505 new_jmeths++;
2506 }
2507 }
2508 if (new_jmeths != 0) {
2509 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2510 }
2511 }
2512
2513 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2514 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2515 int idnum = method->method_idnum();
2516 jmethodID* jmeths = methods_jmethod_ids_acquire();
2517 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2518 }
2519
2520 inline DependencyContext InstanceKlass::dependencies() {
2521 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2522 return dep_context;
2523 }
2524
2525 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2526 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2527 }
2528
2529 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2530 dependencies().add_dependent_nmethod(nm);
2531 }
2532
2533 void InstanceKlass::clean_dependency_context() {
2534 dependencies().clean_unloading_dependents();
2535 }
2536
2537 #ifndef PRODUCT
2538 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2539 dependencies().print_dependent_nmethods(verbose);
2540 }
2541
2542 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2543 return dependencies().is_dependent_nmethod(nm);
2544 }
2545 #endif //PRODUCT
2546
2547 void InstanceKlass::clean_weak_instanceklass_links() {
2548 clean_implementors_list();
2549 clean_method_data();
2550 }
2551
2552 void InstanceKlass::clean_implementors_list() {
2553 assert(is_loader_alive(), "this klass should be live");
2554 if (is_interface()) {
2555 assert (ClassUnloading, "only called for ClassUnloading");
2556 for (;;) {
2557 // Use load_acquire due to competing with inserts
2558 InstanceKlass* volatile* iklass = adr_implementor();
2559 assert(iklass != nullptr, "Klass must not be null");
2560 InstanceKlass* impl = Atomic::load_acquire(iklass);
2561 if (impl != nullptr && !impl->is_loader_alive()) {
2562 // null this field, might be an unloaded instance klass or null
2563 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2564 // Successfully unlinking implementor.
2565 if (log_is_enabled(Trace, class, unload)) {
2566 ResourceMark rm;
2567 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2568 }
2569 return;
2570 }
2571 } else {
2572 return;
2573 }
2574 }
2575 }
2576 }
2577
2578 void InstanceKlass::clean_method_data() {
2579 for (int m = 0; m < methods()->length(); m++) {
2580 MethodData* mdo = methods()->at(m)->method_data();
2581 if (mdo != nullptr) {
2582 mdo->clean_method_data(/*always_clean*/false);
2583 }
2584 }
2585 }
2586
2587 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2588 Klass::metaspace_pointers_do(it);
2589
2590 if (log_is_enabled(Trace, cds)) {
2591 ResourceMark rm;
2592 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2593 }
2594
2595 it->push(&_annotations);
2596 it->push((Klass**)&_array_klasses);
2597 if (!is_rewritten()) {
2598 it->push(&_constants, MetaspaceClosure::_writable);
2599 } else {
2600 it->push(&_constants);
2601 }
2602 it->push(&_inner_classes);
2603 #if INCLUDE_JVMTI
2604 it->push(&_previous_versions);
2605 #endif
2606 #if INCLUDE_CDS
2607 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2608 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2609 // be writable. The length check on the _methods is necessary because classes which
2610 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2611 if (_methods != nullptr && _methods->length() > 0 &&
2612 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2613 // To handle jsr bytecode, new Method* maybe stored into _methods
2614 it->push(&_methods, MetaspaceClosure::_writable);
2615 } else {
2616 #endif
2617 it->push(&_methods);
2618 #if INCLUDE_CDS
2619 }
2620 #endif
2621 it->push(&_default_methods);
2622 it->push(&_local_interfaces);
2623 it->push(&_transitive_interfaces);
2624 it->push(&_method_ordering);
2625 if (!is_rewritten()) {
2626 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2627 } else {
2628 it->push(&_default_vtable_indices);
2629 }
2630
2631 it->push(&_fieldinfo_stream);
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 if (is_linked()) {
2664 assert(can_be_verified_at_dumptime(), "must be");
2665 // Remember this so we can avoid walking the hierarchy at runtime.
2666 set_verified_at_dump_time();
2667 }
2668 _misc_flags.set_has_init_deps_processed(false);
2669
2670 Klass::remove_unshareable_info();
2671
2672 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2673 // Classes are attempted to link during dumping and may fail,
2674 // but these classes are still in the dictionary and class list in CLD.
2675 // If the class has failed verification, there is nothing else to remove.
2676 return;
2677 }
2678
2679 // Reset to the 'allocated' state to prevent any premature accessing to
2680 // a shared class at runtime while the class is still being loaded and
2681 // restored. A class' init_state is set to 'loaded' at runtime when it's
2682 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2683 _init_state = allocated;
2684
2685 { // Otherwise this needs to take out the Compile_lock.
2686 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2687 init_implementor();
2688 }
2689
2690 // Call remove_unshareable_info() on other objects that belong to this class, except
2691 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2692 // ArchiveBuilder::make_klasses_shareable(),
2693
2694 for (int i = 0; i < methods()->length(); i++) {
2695 Method* m = methods()->at(i);
2696 m->remove_unshareable_info();
2697 }
2698
2699 // do array classes also.
2700 if (array_klasses() != nullptr) {
2701 array_klasses()->remove_unshareable_info();
2702 }
2703
2704 // These are not allocated from metaspace. They are safe to set to null.
2705 _source_debug_extension = nullptr;
2706 _dep_context = nullptr;
2707 _osr_nmethods_head = nullptr;
2708 #if INCLUDE_JVMTI
2709 _breakpoints = nullptr;
2710 _previous_versions = nullptr;
2711 _cached_class_file = nullptr;
2712 _jvmti_cached_class_field_map = nullptr;
2713 #endif
2714
2715 _init_thread = nullptr;
2716 _methods_jmethod_ids = nullptr;
2717 _jni_ids = nullptr;
2718 _oop_map_cache = nullptr;
2719 if (CDSConfig::is_dumping_invokedynamic() && HeapShared::is_lambda_proxy_klass(this)) {
2720 // keep _nest_host
2721 } else {
2722 // clear _nest_host to ensure re-load at runtime
2723 _nest_host = nullptr;
2724 }
2725 init_shared_package_entry();
2726 _dep_context_last_cleaned = 0;
2727 DEBUG_ONLY(_shared_class_load_count = 0);
2728
2729 remove_unshareable_flags();
2730 }
2731
2732 void InstanceKlass::remove_unshareable_flags() {
2733 // clear all the flags/stats that shouldn't be in the archived version
2734 assert(!is_scratch_class(), "must be");
2735 assert(!has_been_redefined(), "must be");
2736 #if INCLUDE_JVMTI
2737 set_is_being_redefined(false);
2738 #endif
2739 set_has_resolved_methods(false);
2740 }
2741
2742 void InstanceKlass::remove_java_mirror() {
2743 Klass::remove_java_mirror();
2744
2745 // do array classes also.
2746 if (array_klasses() != nullptr) {
2747 array_klasses()->remove_java_mirror();
2748 }
2749 }
2750
2751 void InstanceKlass::init_shared_package_entry() {
2752 assert(CDSConfig::is_dumping_archive(), "must be");
2753 #if !INCLUDE_CDS_JAVA_HEAP
2754 _package_entry = nullptr;
2755 #else
2756 if (CDSConfig::is_dumping_full_module_graph()) {
2757 if (is_shared_unregistered_class()) {
2758 _package_entry = nullptr;
2759 } else {
2760 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2761 }
2762 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2763 CDSConfig::is_using_full_module_graph() &&
2764 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2765 // _package_entry is an archived package in the base archive. Leave it as is.
2766 } else {
2767 _package_entry = nullptr;
2768 }
2769 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2770 #endif
2771 }
2772
2773 void InstanceKlass::compute_has_loops_flag_for_methods() {
2774 Array<Method*>* methods = this->methods();
2775 for (int index = 0; index < methods->length(); ++index) {
2776 Method* m = methods->at(index);
2777 if (!m->is_overpass()) { // work around JDK-8305771
2778 m->compute_has_loops_flag();
2779 }
2780 }
2781 }
2782
2783 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2784 PackageEntry* pkg_entry, TRAPS) {
2785 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2786 // before the InstanceKlass is added to the SystemDictionary. Make
2787 // sure the current state is <loaded.
2788 assert(!is_loaded(), "invalid init state");
2789 assert(!shared_loading_failed(), "Must not try to load failed class again");
2790 set_package(loader_data, pkg_entry, CHECK);
2791 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2792
2793 Array<Method*>* methods = this->methods();
2794 int num_methods = methods->length();
2795 for (int index = 0; index < num_methods; ++index) {
2796 methods->at(index)->restore_unshareable_info(CHECK);
2797 }
2798 #if INCLUDE_JVMTI
2799 if (JvmtiExport::has_redefined_a_class()) {
2800 // Reinitialize vtable because RedefineClasses may have changed some
2801 // entries in this vtable for super classes so the CDS vtable might
2802 // point to old or obsolete entries. RedefineClasses doesn't fix up
2803 // vtables in the shared system dictionary, only the main one.
2804 // It also redefines the itable too so fix that too.
2805 // First fix any default methods that point to a super class that may
2806 // have been redefined.
2807 bool trace_name_printed = false;
2808 adjust_default_methods(&trace_name_printed);
2809 vtable().initialize_vtable();
2810 itable().initialize_itable();
2811 }
2812 #endif
2813
2814 // restore constant pool resolved references
2815 constants()->restore_unshareable_info(CHECK);
2816
2817 if (array_klasses() != nullptr) {
2818 // To get a consistent list of classes we need MultiArray_lock to ensure
2819 // array classes aren't observed while they are being restored.
2820 RecursiveLocker rl(MultiArray_lock, THREAD);
2821 assert(this == array_klasses()->bottom_klass(), "sanity");
2822 // Array classes have null protection domain.
2823 // --> see ArrayKlass::complete_create_array_klass()
2824 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2825 }
2826
2827 // Initialize @ValueBased class annotation if not already set in the archived klass.
2828 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2829 set_is_value_based();
2830 }
2831 }
2832
2833 bool InstanceKlass::can_be_verified_at_dumptime() const {
2834 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2835 return true;
2836 }
2837
2838 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2839 // This is a class that was dumped into the base archive, so we know
2840 // it was verified at dump time.
2841 return true;
2842 }
2843
2844 if (CDSConfig::is_dumping_invokedynamic()) {
2845 // FIXME: this works around JDK-8315719
2846 return true;
2847 }
2848
2849 // Check if a class or any of its supertypes has a version older than 50.
2850 // CDS will not perform verification of old classes during dump time because
2851 // without changing the old verifier, the verification constraint cannot be
2852 // retrieved during dump time.
2853 // Verification of archived old classes will be performed during run time.
2854 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2855 return false;
2856 }
2857 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2858 return false;
2859 }
2860 Array<InstanceKlass*>* interfaces = local_interfaces();
2861 int len = interfaces->length();
2862 for (int i = 0; i < len; i++) {
2863 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2864 return false;
2865 }
2866 }
2867 return true;
2868 }
2869
2870 bool InstanceKlass::methods_contain_jsr_bytecode() const {
2871 Thread* thread = Thread::current();
2872 for (int i = 0; i < _methods->length(); i++) {
2873 methodHandle m(thread, _methods->at(i));
2874 BytecodeStream bcs(m);
2875 while (!bcs.is_last_bytecode()) {
2876 Bytecodes::Code opcode = bcs.next();
2877 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
2878 return true;
2879 }
2880 }
2881 }
2882 return false;
2883 }
2884
2885 int InstanceKlass::shared_class_loader_type() const {
2886 if (is_shared_boot_class()) {
2887 return ClassLoader::BOOT_LOADER;
2888 } else if (is_shared_platform_class()) {
2889 return ClassLoader::PLATFORM_LOADER;
2890 } else if (is_shared_app_class()) {
2891 return ClassLoader::APP_LOADER;
2892 } else {
2893 return ClassLoader::OTHER;
2894 }
2895 }
2896 #endif // INCLUDE_CDS
2897
2898 #if INCLUDE_JVMTI
2899 static void clear_all_breakpoints(Method* m) {
2900 m->clear_all_breakpoints();
2901 }
2902 #endif
2903
2904 void InstanceKlass::unload_class(InstanceKlass* ik) {
2905
2906 if (ik->is_scratch_class()) {
2907 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2908 return;
2909 }
2910 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2911
2912 // Release dependencies.
2913 ik->dependencies().remove_all_dependents();
2914
2915 // notify the debugger
2916 if (JvmtiExport::should_post_class_unload()) {
2917 JvmtiExport::post_class_unload(ik);
2918 }
2919
2920 // notify ClassLoadingService of class unload
2921 ClassLoadingService::notify_class_unloaded(ik);
2922
2923 SystemDictionaryShared::handle_class_unloading(ik);
2924
2925 if (log_is_enabled(Info, class, unload)) {
2926 ResourceMark rm;
2927 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2928 }
2929
2930 Events::log_class_unloading(Thread::current(), ik);
2931
2932 #if INCLUDE_JFR
2933 assert(ik != nullptr, "invariant");
2934 EventClassUnload event;
2935 event.set_unloadedClass(ik);
2936 event.set_definingClassLoader(ik->class_loader_data());
2937 event.commit();
2938 #endif
2939 }
2940
2941 static void method_release_C_heap_structures(Method* m) {
2942 m->release_C_heap_structures();
2943 }
2944
2945 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2946 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2947 // Clean up C heap
2948 Klass::release_C_heap_structures();
2949
2950 // Deallocate and call destructors for MDO mutexes
2951 if (release_sub_metadata) {
2952 methods_do(method_release_C_heap_structures);
2953 }
2954
2955 // Deallocate oop map cache
2956 if (_oop_map_cache != nullptr) {
2957 delete _oop_map_cache;
2958 _oop_map_cache = nullptr;
2959 }
2960
2961 // Deallocate JNI identifiers for jfieldIDs
2962 JNIid::deallocate(jni_ids());
2963 set_jni_ids(nullptr);
2964
2965 jmethodID* jmeths = methods_jmethod_ids_acquire();
2966 if (jmeths != nullptr) {
2967 release_set_methods_jmethod_ids(nullptr);
2968 FreeHeap(jmeths);
2969 }
2970
2971 assert(_dep_context == nullptr,
2972 "dependencies should already be cleaned");
2973
2974 #if INCLUDE_JVMTI
2975 // Deallocate breakpoint records
2976 if (breakpoints() != nullptr) {
2977 methods_do(clear_all_breakpoints);
2978 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2979 }
2980
2981 // deallocate the cached class file
2982 if (_cached_class_file != nullptr) {
2983 os::free(_cached_class_file);
2984 _cached_class_file = nullptr;
2985 }
2986 #endif
2987
2988 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2989
2990 if (release_sub_metadata) {
2991 constants()->release_C_heap_structures();
2992 }
2993 }
2994
2995 // The constant pool is on stack if any of the methods are executing or
2996 // referenced by handles.
2997 bool InstanceKlass::on_stack() const {
2998 return _constants->on_stack();
2999 }
3000
3001 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3002 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3003 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3004
3005 // minor and major version numbers of class file
3006 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3007 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3008 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3009 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3010
3011 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3012 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3013 if (ik->constants()->version() == version) {
3014 return ik;
3015 }
3016 }
3017 return nullptr;
3018 }
3019
3020 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3021 if (array == nullptr) {
3022 _source_debug_extension = nullptr;
3023 } else {
3024 // Adding one to the attribute length in order to store a null terminator
3025 // character could cause an overflow because the attribute length is
3026 // already coded with an u4 in the classfile, but in practice, it's
3027 // unlikely to happen.
3028 assert((length+1) > length, "Overflow checking");
3029 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3030 for (int i = 0; i < length; i++) {
3031 sde[i] = array[i];
3032 }
3033 sde[length] = '\0';
3034 _source_debug_extension = sde;
3035 }
3036 }
3037
3038 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3039 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3040 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3041
3042 const char* InstanceKlass::signature_name() const {
3043
3044 // Get the internal name as a c string
3045 const char* src = (const char*) (name()->as_C_string());
3046 const int src_length = (int)strlen(src);
3047
3048 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3049
3050 // Add L as type indicator
3051 int dest_index = 0;
3052 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3053
3054 // Add the actual class name
3055 for (int src_index = 0; src_index < src_length; ) {
3056 dest[dest_index++] = src[src_index++];
3057 }
3058
3059 if (is_hidden()) { // Replace the last '+' with a '.'.
3060 for (int index = (int)src_length; index > 0; index--) {
3061 if (dest[index] == '+') {
3062 dest[index] = JVM_SIGNATURE_DOT;
3063 break;
3064 }
3065 }
3066 }
3067
3068 // Add the semicolon and the null
3069 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3070 dest[dest_index] = '\0';
3071 return dest;
3072 }
3073
3074 ModuleEntry* InstanceKlass::module() const {
3075 if (is_hidden() &&
3076 in_unnamed_package() &&
3077 class_loader_data()->has_class_mirror_holder()) {
3078 // For a non-strong hidden class defined to an unnamed package,
3079 // its (class held) CLD will not have an unnamed module created for it.
3080 // Two choices to find the correct ModuleEntry:
3081 // 1. If hidden class is within a nest, use nest host's module
3082 // 2. Find the unnamed module off from the class loader
3083 // For now option #2 is used since a nest host is not set until
3084 // after the instance class is created in jvm_lookup_define_class().
3085 if (class_loader_data()->is_boot_class_loader_data()) {
3086 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3087 } else {
3088 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3089 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3090 return java_lang_Module::module_entry(module);
3091 }
3092 }
3093
3094 // Class is in a named package
3095 if (!in_unnamed_package()) {
3096 return _package_entry->module();
3097 }
3098
3099 // Class is in an unnamed package, return its loader's unnamed module
3100 return class_loader_data()->unnamed_module();
3101 }
3102
3103 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3104
3105 // ensure java/ packages only loaded by boot or platform builtin loaders
3106 // not needed for shared class since CDS does not archive prohibited classes.
3107 if (!is_shared()) {
3108 check_prohibited_package(name(), loader_data, CHECK);
3109 }
3110
3111 if (is_shared() && _package_entry != nullptr) {
3112 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3113 // we can use the saved package
3114 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3115 return;
3116 } else {
3117 _package_entry = nullptr;
3118 }
3119 }
3120
3121 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3122 // it returns, so we need to decrement it when the current function exits.
3123 TempNewSymbol from_class_name =
3124 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3125
3126 Symbol* pkg_name;
3127 if (pkg_entry != nullptr) {
3128 pkg_name = pkg_entry->name();
3129 } else {
3130 pkg_name = from_class_name;
3131 }
3132
3133 if (pkg_name != nullptr && loader_data != nullptr) {
3134
3135 // Find in class loader's package entry table.
3136 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3137
3138 // If the package name is not found in the loader's package
3139 // entry table, it is an indication that the package has not
3140 // been defined. Consider it defined within the unnamed module.
3141 if (_package_entry == nullptr) {
3142
3143 if (!ModuleEntryTable::javabase_defined()) {
3144 // Before java.base is defined during bootstrapping, define all packages in
3145 // the java.base module. If a non-java.base package is erroneously placed
3146 // in the java.base module it will be caught later when java.base
3147 // is defined by ModuleEntryTable::verify_javabase_packages check.
3148 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3149 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3150 } else {
3151 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3152 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3153 }
3154
3155 // A package should have been successfully created
3156 DEBUG_ONLY(ResourceMark rm(THREAD));
3157 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3158 name()->as_C_string(), loader_data->loader_name_and_id());
3159 }
3160
3161 if (log_is_enabled(Debug, module)) {
3162 ResourceMark rm(THREAD);
3163 ModuleEntry* m = _package_entry->module();
3164 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3165 external_name(),
3166 pkg_name->as_C_string(),
3167 loader_data->loader_name_and_id(),
3168 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3169 }
3170 } else {
3171 ResourceMark rm(THREAD);
3172 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3173 external_name(),
3174 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3175 UNNAMED_MODULE);
3176 }
3177 }
3178
3179 // Function set_classpath_index ensures that for a non-null _package_entry
3180 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3181 // It then sets the classpath_index in the package entry record.
3182 //
3183 // The classpath_index field is used to find the entry on the boot loader class
3184 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3185 // in an unnamed module. It is also used to indicate (for all packages whose
3186 // classes are loaded by the boot loader) that at least one of the package's
3187 // classes has been loaded.
3188 void InstanceKlass::set_classpath_index(s2 path_index) {
3189 if (_package_entry != nullptr) {
3190 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3191 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3192 assert(path_index != -1, "Unexpected classpath_index");
3193 _package_entry->set_classpath_index(path_index);
3194 }
3195 }
3196
3197 // different versions of is_same_class_package
3198
3199 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3200 oop classloader1 = this->class_loader();
3201 PackageEntry* classpkg1 = this->package();
3202 if (class2->is_objArray_klass()) {
3203 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3204 }
3205
3206 oop classloader2;
3207 PackageEntry* classpkg2;
3208 if (class2->is_instance_klass()) {
3209 classloader2 = class2->class_loader();
3210 classpkg2 = class2->package();
3211 } else {
3212 assert(class2->is_typeArray_klass(), "should be type array");
3213 classloader2 = nullptr;
3214 classpkg2 = nullptr;
3215 }
3216
3217 // Same package is determined by comparing class loader
3218 // and package entries. Both must be the same. This rule
3219 // applies even to classes that are defined in the unnamed
3220 // package, they still must have the same class loader.
3221 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3222 return true;
3223 }
3224
3225 return false;
3226 }
3227
3228 // return true if this class and other_class are in the same package. Classloader
3229 // and classname information is enough to determine a class's package
3230 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3231 const Symbol* other_class_name) const {
3232 if (class_loader() != other_class_loader) {
3233 return false;
3234 }
3235 if (name()->fast_compare(other_class_name) == 0) {
3236 return true;
3237 }
3238
3239 {
3240 ResourceMark rm;
3241
3242 bool bad_class_name = false;
3243 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3244 if (bad_class_name) {
3245 return false;
3246 }
3247 // Check that package_from_class_name() returns null, not "", if there is no package.
3248 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3249
3250 const Symbol* const this_package_name =
3251 this->package() != nullptr ? this->package()->name() : nullptr;
3252
3253 if (this_package_name == nullptr || other_pkg == nullptr) {
3254 // One of the two doesn't have a package. Only return true if the other
3255 // one also doesn't have a package.
3256 return this_package_name == other_pkg;
3257 }
3258
3259 // Check if package is identical
3260 return this_package_name->fast_compare(other_pkg) == 0;
3261 }
3262 }
3263
3264 static bool is_prohibited_package_slow(Symbol* class_name) {
3265 // Caller has ResourceMark
3266 int length;
3267 jchar* unicode = class_name->as_unicode(length);
3268 return (length >= 5 &&
3269 unicode[0] == 'j' &&
3270 unicode[1] == 'a' &&
3271 unicode[2] == 'v' &&
3272 unicode[3] == 'a' &&
3273 unicode[4] == '/');
3274 }
3275
3276 // Only boot and platform class loaders can define classes in "java/" packages.
3277 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3278 ClassLoaderData* loader_data,
3279 TRAPS) {
3280 if (!loader_data->is_boot_class_loader_data() &&
3281 !loader_data->is_platform_class_loader_data() &&
3282 class_name != nullptr && class_name->utf8_length() >= 5) {
3283 ResourceMark rm(THREAD);
3284 bool prohibited;
3285 const u1* base = class_name->base();
3286 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3287 prohibited = is_prohibited_package_slow(class_name);
3288 } else {
3289 char* name = class_name->as_C_string();
3290 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3291 }
3292 if (prohibited) {
3293 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3294 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3295 char* name = pkg_name->as_C_string();
3296 const char* class_loader_name = loader_data->loader_name_and_id();
3297 StringUtils::replace_no_expand(name, "/", ".");
3298 const char* msg_text1 = "Class loader (instance of): ";
3299 const char* msg_text2 = " tried to load prohibited package name: ";
3300 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3301 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3302 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3303 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3304 }
3305 }
3306 return;
3307 }
3308
3309 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3310 constantPoolHandle i_cp(THREAD, constants());
3311 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3312 int ioff = iter.inner_class_info_index();
3313 if (ioff != 0) {
3314 // Check to see if the name matches the class we're looking for
3315 // before attempting to find the class.
3316 if (i_cp->klass_name_at_matches(this, ioff)) {
3317 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3318 if (this == inner_klass) {
3319 *ooff = iter.outer_class_info_index();
3320 *noff = iter.inner_name_index();
3321 return true;
3322 }
3323 }
3324 }
3325 }
3326 return false;
3327 }
3328
3329 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3330 InstanceKlass* outer_klass = nullptr;
3331 *inner_is_member = false;
3332 int ooff = 0, noff = 0;
3333 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3334 if (has_inner_classes_attr) {
3335 constantPoolHandle i_cp(THREAD, constants());
3336 if (ooff != 0) {
3337 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3338 if (!ok->is_instance_klass()) {
3339 // If the outer class is not an instance klass then it cannot have
3340 // declared any inner classes.
3341 ResourceMark rm(THREAD);
3342 Exceptions::fthrow(
3343 THREAD_AND_LOCATION,
3344 vmSymbols::java_lang_IncompatibleClassChangeError(),
3345 "%s and %s disagree on InnerClasses attribute",
3346 ok->external_name(),
3347 external_name());
3348 return nullptr;
3349 }
3350 outer_klass = InstanceKlass::cast(ok);
3351 *inner_is_member = true;
3352 }
3353 if (nullptr == outer_klass) {
3354 // It may be a local class; try for that.
3355 int encl_method_class_idx = enclosing_method_class_index();
3356 if (encl_method_class_idx != 0) {
3357 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3358 outer_klass = InstanceKlass::cast(ok);
3359 *inner_is_member = false;
3360 }
3361 }
3362 }
3363
3364 // If no inner class attribute found for this class.
3365 if (nullptr == outer_klass) return nullptr;
3366
3367 // Throws an exception if outer klass has not declared k as an inner klass
3368 // We need evidence that each klass knows about the other, or else
3369 // the system could allow a spoof of an inner class to gain access rights.
3370 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3371 return outer_klass;
3372 }
3373
3374 jint InstanceKlass::compute_modifier_flags() const {
3375 jint access = access_flags().as_int();
3376
3377 // But check if it happens to be member class.
3378 InnerClassesIterator iter(this);
3379 for (; !iter.done(); iter.next()) {
3380 int ioff = iter.inner_class_info_index();
3381 // Inner class attribute can be zero, skip it.
3382 // Strange but true: JVM spec. allows null inner class refs.
3383 if (ioff == 0) continue;
3384
3385 // only look at classes that are already loaded
3386 // since we are looking for the flags for our self.
3387 Symbol* inner_name = constants()->klass_name_at(ioff);
3388 if (name() == inner_name) {
3389 // This is really a member class.
3390 access = iter.inner_access_flags();
3391 break;
3392 }
3393 }
3394 // Remember to strip ACC_SUPER bit
3395 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3396 }
3397
3398 jint InstanceKlass::jvmti_class_status() const {
3399 jint result = 0;
3400
3401 if (is_linked()) {
3402 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3403 }
3404
3405 if (is_initialized()) {
3406 assert(is_linked(), "Class status is not consistent");
3407 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3408 }
3409 if (is_in_error_state()) {
3410 result |= JVMTI_CLASS_STATUS_ERROR;
3411 }
3412 return result;
3413 }
3414
3415 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3416 bool implements_interface; // initialized by method_at_itable_or_null
3417 Method* m = method_at_itable_or_null(holder, index,
3418 implements_interface); // out parameter
3419 if (m != nullptr) {
3420 assert(implements_interface, "sanity");
3421 return m;
3422 } else if (implements_interface) {
3423 // Throw AbstractMethodError since corresponding itable slot is empty.
3424 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3425 } else {
3426 // If the interface isn't implemented by the receiver class,
3427 // the VM should throw IncompatibleClassChangeError.
3428 ResourceMark rm(THREAD);
3429 stringStream ss;
3430 bool same_module = (module() == holder->module());
3431 ss.print("Receiver class %s does not implement "
3432 "the interface %s defining the method to be called "
3433 "(%s%s%s)",
3434 external_name(), holder->external_name(),
3435 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3436 (same_module) ? "" : "; ",
3437 (same_module) ? "" : holder->class_in_module_of_loader());
3438 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3439 }
3440 }
3441
3442 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3443 klassItable itable(this);
3444 for (int i = 0; i < itable.size_offset_table(); i++) {
3445 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3446 if (offset_entry->interface_klass() == holder) {
3447 implements_interface = true;
3448 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3449 Method* m = ime[index].method();
3450 return m;
3451 }
3452 }
3453 implements_interface = false;
3454 return nullptr; // offset entry not found
3455 }
3456
3457 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3458 assert(is_linked(), "required");
3459 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3460 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3461
3462 int vtable_index = Method::invalid_vtable_index;
3463 Symbol* name = intf_method->name();
3464 Symbol* signature = intf_method->signature();
3465
3466 // First check in default method array
3467 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3468 int index = find_method_index(default_methods(),
3469 name, signature,
3470 Klass::OverpassLookupMode::find,
3471 Klass::StaticLookupMode::find,
3472 Klass::PrivateLookupMode::find);
3473 if (index >= 0) {
3474 vtable_index = default_vtable_indices()->at(index);
3475 }
3476 }
3477 if (vtable_index == Method::invalid_vtable_index) {
3478 // get vtable_index for miranda methods
3479 klassVtable vt = vtable();
3480 vtable_index = vt.index_of_miranda(name, signature);
3481 }
3482 return vtable_index;
3483 }
3484
3485 #if INCLUDE_JVMTI
3486 // update default_methods for redefineclasses for methods that are
3487 // not yet in the vtable due to concurrent subclass define and superinterface
3488 // redefinition
3489 // Note: those in the vtable, should have been updated via adjust_method_entries
3490 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3491 // search the default_methods for uses of either obsolete or EMCP methods
3492 if (default_methods() != nullptr) {
3493 for (int index = 0; index < default_methods()->length(); index ++) {
3494 Method* old_method = default_methods()->at(index);
3495 if (old_method == nullptr || !old_method->is_old()) {
3496 continue; // skip uninteresting entries
3497 }
3498 assert(!old_method->is_deleted(), "default methods may not be deleted");
3499 Method* new_method = old_method->get_new_method();
3500 default_methods()->at_put(index, new_method);
3501
3502 if (log_is_enabled(Info, redefine, class, update)) {
3503 ResourceMark rm;
3504 if (!(*trace_name_printed)) {
3505 log_info(redefine, class, update)
3506 ("adjust: klassname=%s default methods from name=%s",
3507 external_name(), old_method->method_holder()->external_name());
3508 *trace_name_printed = true;
3509 }
3510 log_debug(redefine, class, update, vtables)
3511 ("default method update: %s(%s) ",
3512 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3513 }
3514 }
3515 }
3516 }
3517 #endif // INCLUDE_JVMTI
3518
3519 // On-stack replacement stuff
3520 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3521 assert_lock_strong(NMethodState_lock);
3522 #ifndef PRODUCT
3523 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3524 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3525 "redundant OSR recompilation detected. memory leak in CodeCache!");
3526 #endif
3527 // only one compilation can be active
3528 assert(n->is_osr_method(), "wrong kind of nmethod");
3529 n->set_osr_link(osr_nmethods_head());
3530 set_osr_nmethods_head(n);
3531 // Raise the highest osr level if necessary
3532 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3533
3534 // Get rid of the osr methods for the same bci that have lower levels.
3535 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3536 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3537 if (inv != nullptr && inv->is_in_use()) {
3538 inv->make_not_entrant();
3539 }
3540 }
3541 }
3542
3543 // Remove osr nmethod from the list. Return true if found and removed.
3544 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3545 // This is a short non-blocking critical region, so the no safepoint check is ok.
3546 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3547 assert(n->is_osr_method(), "wrong kind of nmethod");
3548 nmethod* last = nullptr;
3549 nmethod* cur = osr_nmethods_head();
3550 int max_level = CompLevel_none; // Find the max comp level excluding n
3551 Method* m = n->method();
3552 // Search for match
3553 bool found = false;
3554 while(cur != nullptr && cur != n) {
3555 if (m == cur->method()) {
3556 // Find max level before n
3557 max_level = MAX2(max_level, cur->comp_level());
3558 }
3559 last = cur;
3560 cur = cur->osr_link();
3561 }
3562 nmethod* next = nullptr;
3563 if (cur == n) {
3564 found = true;
3565 next = cur->osr_link();
3566 if (last == nullptr) {
3567 // Remove first element
3568 set_osr_nmethods_head(next);
3569 } else {
3570 last->set_osr_link(next);
3571 }
3572 }
3573 n->set_osr_link(nullptr);
3574 cur = next;
3575 while (cur != nullptr) {
3576 // Find max level after n
3577 if (m == cur->method()) {
3578 max_level = MAX2(max_level, cur->comp_level());
3579 }
3580 cur = cur->osr_link();
3581 }
3582 m->set_highest_osr_comp_level(max_level);
3583 return found;
3584 }
3585
3586 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3587 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3588 nmethod* osr = osr_nmethods_head();
3589 int found = 0;
3590 while (osr != nullptr) {
3591 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3592 if (osr->method() == m) {
3593 deopt_scope->mark(osr);
3594 found++;
3595 }
3596 osr = osr->osr_link();
3597 }
3598 return found;
3599 }
3600
3601 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3602 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3603 nmethod* osr = osr_nmethods_head();
3604 nmethod* best = nullptr;
3605 while (osr != nullptr) {
3606 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3607 // There can be a time when a c1 osr method exists but we are waiting
3608 // for a c2 version. When c2 completes its osr nmethod we will trash
3609 // the c1 version and only be able to find the c2 version. However
3610 // while we overflow in the c1 code at back branches we don't want to
3611 // try and switch to the same code as we are already running
3612
3613 if (osr->method() == m &&
3614 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3615 if (match_level) {
3616 if (osr->comp_level() == comp_level) {
3617 // Found a match - return it.
3618 return osr;
3619 }
3620 } else {
3621 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3622 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3623 // Found the best possible - return it.
3624 return osr;
3625 }
3626 best = osr;
3627 }
3628 }
3629 }
3630 osr = osr->osr_link();
3631 }
3632
3633 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3634 if (best != nullptr && best->comp_level() >= comp_level) {
3635 return best;
3636 }
3637 return nullptr;
3638 }
3639
3640 // -----------------------------------------------------------------------------------------------------
3641 // Printing
3642
3643 #define BULLET " - "
3644
3645 static const char* state_names[] = {
3646 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3647 };
3648
3649 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3650 for (int i = 0; i < len; i++) {
3651 intptr_t e = start[i];
3652 st->print("%d : " INTPTR_FORMAT, i, e);
3653 if (MetaspaceObj::is_valid((Metadata*)e)) {
3654 st->print(" ");
3655 ((Metadata*)e)->print_value_on(st);
3656 }
3657 st->cr();
3658 }
3659 }
3660
3661 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3662 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3663 }
3664
3665 const char* InstanceKlass::init_state_name() const {
3666 return state_names[init_state()];
3667 }
3668
3669 const char* InstanceKlass::state2name(ClassState s) {
3670 return state_names[s];
3671 }
3672
3673 void InstanceKlass::print_on(outputStream* st) const {
3674 assert(is_klass(), "must be klass");
3675 Klass::print_on(st);
3676
3677 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3678 st->print(BULLET"klass size: %d", size()); st->cr();
3679 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3680 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3681 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3682 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3683 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3684 st->print(BULLET"sub: ");
3685 Klass* sub = subklass();
3686 int n;
3687 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3688 if (n < MaxSubklassPrintSize) {
3689 sub->print_value_on(st);
3690 st->print(" ");
3691 }
3692 }
3693 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3694 st->cr();
3695
3696 if (is_interface()) {
3697 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3698 if (nof_implementors() == 1) {
3699 st->print_cr(BULLET"implementor: ");
3700 st->print(" ");
3701 implementor()->print_value_on(st);
3702 st->cr();
3703 }
3704 }
3705
3706 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3707 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3708 if (Verbose || WizardMode) {
3709 Array<Method*>* method_array = methods();
3710 for (int i = 0; i < method_array->length(); i++) {
3711 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3712 }
3713 }
3714 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3715 if (default_methods() != nullptr) {
3716 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3717 if (Verbose) {
3718 Array<Method*>* method_array = default_methods();
3719 for (int i = 0; i < method_array->length(); i++) {
3720 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3721 }
3722 }
3723 }
3724 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3725 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3726 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3727
3728 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3729 if (UseSecondarySupersTable) {
3730 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3731 st->print(BULLET"bitmap: " UINTX_FORMAT_X_0, _bitmap); st->cr();
3732 }
3733 if (secondary_supers() != nullptr) {
3734 if (Verbose) {
3735 bool is_hashed = UseSecondarySupersTable && (_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3736 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3737 for (int i = 0; i < _secondary_supers->length(); i++) {
3738 ResourceMark rm; // for external_name()
3739 Klass* secondary_super = _secondary_supers->at(i);
3740 st->print(BULLET"%2d:", i);
3741 if (is_hashed) {
3742 int home_slot = compute_home_slot(secondary_super, _bitmap);
3743 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3744 st->print(" dist:%02d:", distance);
3745 }
3746 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3747 }
3748 }
3749 }
3750 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3751
3752 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3753 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3754 if (source_debug_extension() != nullptr) {
3755 st->print(BULLET"source debug extension: ");
3756 st->print("%s", source_debug_extension());
3757 st->cr();
3758 }
3759 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3760 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3761 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3762 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3763 {
3764 bool have_pv = false;
3765 // previous versions are linked together through the InstanceKlass
3766 for (InstanceKlass* pv_node = previous_versions();
3767 pv_node != nullptr;
3768 pv_node = pv_node->previous_versions()) {
3769 if (!have_pv)
3770 st->print(BULLET"previous version: ");
3771 have_pv = true;
3772 pv_node->constants()->print_value_on(st);
3773 }
3774 if (have_pv) st->cr();
3775 }
3776
3777 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3778 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3779 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3780 print_on_maybe_null(st, BULLET"record components: ", record_components());
3781 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3782 if (java_mirror() != nullptr) {
3783 st->print(BULLET"java mirror: ");
3784 java_mirror()->print_value_on(st);
3785 st->cr();
3786 } else {
3787 st->print_cr(BULLET"java mirror: null");
3788 }
3789 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3790 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3791 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3792 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3793 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3794
3795 FieldPrinter print_static_field(st);
3796 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3797 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3798 FieldPrinter print_nonstatic_field(st);
3799 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3800 ik->print_nonstatic_fields(&print_nonstatic_field);
3801
3802 st->print(BULLET"non-static oop maps: ");
3803 OopMapBlock* map = start_of_nonstatic_oop_maps();
3804 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3805 while (map < end_map) {
3806 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3807 map++;
3808 }
3809 st->cr();
3810 }
3811
3812 void InstanceKlass::print_value_on(outputStream* st) const {
3813 assert(is_klass(), "must be klass");
3814 if (Verbose || WizardMode) access_flags().print_on(st);
3815 name()->print_value_on(st);
3816 }
3817
3818 void FieldPrinter::do_field(fieldDescriptor* fd) {
3819 _st->print(BULLET);
3820 if (_obj == nullptr) {
3821 fd->print_on(_st);
3822 _st->cr();
3823 } else {
3824 fd->print_on_for(_st, _obj);
3825 _st->cr();
3826 }
3827 }
3828
3829
3830 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3831 Klass::oop_print_on(obj, st);
3832
3833 if (this == vmClasses::String_klass()) {
3834 typeArrayOop value = java_lang_String::value(obj);
3835 juint length = java_lang_String::length(obj);
3836 if (value != nullptr &&
3837 value->is_typeArray() &&
3838 length <= (juint) value->length()) {
3839 st->print(BULLET"string: ");
3840 java_lang_String::print(obj, st);
3841 st->cr();
3842 }
3843 }
3844
3845 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3846 FieldPrinter print_field(st, obj);
3847 print_nonstatic_fields(&print_field);
3848
3849 if (this == vmClasses::Class_klass()) {
3850 st->print(BULLET"signature: ");
3851 java_lang_Class::print_signature(obj, st);
3852 st->cr();
3853 Klass* real_klass = java_lang_Class::as_Klass(obj);
3854 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3855 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3856 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3857 }
3858 } else if (this == vmClasses::MethodType_klass()) {
3859 st->print(BULLET"signature: ");
3860 java_lang_invoke_MethodType::print_signature(obj, st);
3861 st->cr();
3862 }
3863 }
3864
3865 #ifndef PRODUCT
3866
3867 bool InstanceKlass::verify_itable_index(int i) {
3868 int method_count = klassItable::method_count_for_interface(this);
3869 assert(i >= 0 && i < method_count, "index out of bounds");
3870 return true;
3871 }
3872
3873 #endif //PRODUCT
3874
3875 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3876 st->print("a ");
3877 name()->print_value_on(st);
3878 obj->print_address_on(st);
3879 if (this == vmClasses::String_klass()
3880 && java_lang_String::value(obj) != nullptr) {
3881 ResourceMark rm;
3882 int len = java_lang_String::length(obj);
3883 int plen = (len < 24 ? len : 12);
3884 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3885 st->print(" = \"%s\"", str);
3886 if (len > plen)
3887 st->print("...[%d]", len);
3888 } else if (this == vmClasses::Class_klass()) {
3889 Klass* k = java_lang_Class::as_Klass(obj);
3890 st->print(" = ");
3891 if (k != nullptr) {
3892 k->print_value_on(st);
3893 } else {
3894 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3895 st->print("%s", tname ? tname : "type?");
3896 }
3897 } else if (this == vmClasses::MethodType_klass()) {
3898 st->print(" = ");
3899 java_lang_invoke_MethodType::print_signature(obj, st);
3900 } else if (java_lang_boxing_object::is_instance(obj)) {
3901 st->print(" = ");
3902 java_lang_boxing_object::print(obj, st);
3903 } else if (this == vmClasses::LambdaForm_klass()) {
3904 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3905 if (vmentry != nullptr) {
3906 st->print(" => ");
3907 vmentry->print_value_on(st);
3908 }
3909 } else if (this == vmClasses::MemberName_klass()) {
3910 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3911 if (vmtarget != nullptr) {
3912 st->print(" = ");
3913 vmtarget->print_value_on(st);
3914 } else {
3915 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3916 oop name = java_lang_invoke_MemberName::name(obj);
3917 if (clazz != nullptr) {
3918 clazz->print_value_on(st);
3919 } else {
3920 st->print("null");
3921 }
3922 st->print(".");
3923 if (name != nullptr) {
3924 name->print_value_on(st);
3925 } else {
3926 st->print("null");
3927 }
3928 }
3929 }
3930 }
3931
3932 const char* InstanceKlass::internal_name() const {
3933 return external_name();
3934 }
3935
3936 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3937 const ModuleEntry* module_entry,
3938 const ClassFileStream* cfs) const {
3939
3940 if (ClassListWriter::is_enabled()) {
3941 ClassListWriter::write(this, cfs);
3942 }
3943
3944 print_class_load_helper(loader_data, module_entry, cfs);
3945 print_class_load_cause_logging();
3946 }
3947
3948 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3949 const ModuleEntry* module_entry,
3950 const ClassFileStream* cfs) const {
3951
3952 if (!log_is_enabled(Info, class, load)) {
3953 return;
3954 }
3955
3956 ResourceMark rm;
3957 LogMessage(class, load) msg;
3958 stringStream info_stream;
3959
3960 // Name and class hierarchy info
3961 info_stream.print("%s", external_name());
3962
3963 // Source
3964 if (cfs != nullptr) {
3965 if (cfs->source() != nullptr) {
3966 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3967 if (module_name != nullptr) {
3968 // When the boot loader created the stream, it didn't know the module name
3969 // yet. Let's format it now.
3970 if (cfs->from_boot_loader_modules_image()) {
3971 info_stream.print(" source: jrt:/%s", module_name);
3972 } else {
3973 info_stream.print(" source: %s", cfs->source());
3974 }
3975 } else {
3976 info_stream.print(" source: %s", cfs->source());
3977 }
3978 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3979 Thread* current = Thread::current();
3980 Klass* caller = current->is_Java_thread() ?
3981 JavaThread::cast(current)->security_get_caller_class(1):
3982 nullptr;
3983 // caller can be null, for example, during a JVMTI VM_Init hook
3984 if (caller != nullptr) {
3985 info_stream.print(" source: instance of %s", caller->external_name());
3986 } else {
3987 // source is unknown
3988 }
3989 } else {
3990 oop class_loader = loader_data->class_loader();
3991 info_stream.print(" source: %s", class_loader->klass()->external_name());
3992 }
3993 } else {
3994 assert(this->is_shared(), "must be");
3995 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3996 info_stream.print(" source: shared objects file (top)");
3997 } else {
3998 info_stream.print(" source: shared objects file");
3999 }
4000 }
4001
4002 info_stream.print(" loader:");
4003 if (is_shared()) {
4004 info_stream.print(" %s", SystemDictionaryShared::class_loader_name_for_shared((Klass*)this));
4005 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4006 info_stream.print(" boot_loader");
4007 } else {
4008 oop class_loader = loader_data->class_loader();
4009 if (class_loader != nullptr) {
4010 info_stream.print(" %s", class_loader->klass()->external_name());
4011 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4012 if (cl_name_and_id != nullptr) {
4013 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4014 }
4015 } else {
4016 info_stream.print(" null");
4017 }
4018 }
4019 msg.info("%s", info_stream.as_string());
4020
4021 if (log_is_enabled(Debug, class, load)) {
4022 stringStream debug_stream;
4023
4024 // Class hierarchy info
4025 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4026 p2i(this), p2i(superklass()));
4027
4028 // Interfaces
4029 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4030 debug_stream.print(" interfaces:");
4031 int length = local_interfaces()->length();
4032 for (int i = 0; i < length; i++) {
4033 debug_stream.print(" " PTR_FORMAT,
4034 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4035 }
4036 }
4037
4038 // Class loader
4039 debug_stream.print(" loader: [");
4040 loader_data->print_value_on(&debug_stream);
4041 debug_stream.print("]");
4042
4043 // Classfile checksum
4044 if (cfs) {
4045 debug_stream.print(" bytes: %d checksum: %08x",
4046 cfs->length(),
4047 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4048 cfs->length()));
4049 }
4050
4051 msg.debug("%s", debug_stream.as_string());
4052 }
4053 }
4054
4055 void InstanceKlass::print_class_load_cause_logging() const {
4056 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4057 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4058 JavaThread* current = JavaThread::current();
4059 ResourceMark rm(current);
4060 const char* name = external_name();
4061
4062 if (LogClassLoadingCauseFor == nullptr ||
4063 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4064 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4065 return;
4066 }
4067
4068 // Log Java stack first
4069 {
4070 LogMessage(class, load, cause) msg;
4071 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4072
4073 info_stream.print_cr("Java stack when loading %s:", name);
4074 current->print_stack_on(&info_stream);
4075 }
4076
4077 // Log native stack second
4078 if (log_cause_native) {
4079 // Log to string first so that lines can be indented
4080 stringStream stack_stream;
4081 char buf[O_BUFLEN];
4082 address lastpc = nullptr;
4083 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4084 // We have printed the native stack in platform-specific code,
4085 // so nothing else to do in this case.
4086 } else {
4087 frame f = os::current_frame();
4088 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4089 -1 /* max stack_stream */, buf, O_BUFLEN);
4090 }
4091
4092 LogMessage(class, load, cause, native) msg;
4093 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4094 info_stream.print_cr("Native stack when loading %s:", name);
4095
4096 // Print each native stack line to the log
4097 int size = (int) stack_stream.size();
4098 char* stack = stack_stream.as_string();
4099 char* stack_end = stack + size;
4100 char* line_start = stack;
4101 for (char* p = stack; p < stack_end; p++) {
4102 if (*p == '\n') {
4103 *p = '\0';
4104 info_stream.print_cr("\t%s", line_start);
4105 line_start = p + 1;
4106 }
4107 }
4108 if (line_start < stack_end) {
4109 info_stream.print_cr("\t%s", line_start);
4110 }
4111 }
4112 }
4113 }
4114
4115 // Verification
4116
4117 class VerifyFieldClosure: public BasicOopIterateClosure {
4118 protected:
4119 template <class T> void do_oop_work(T* p) {
4120 oop obj = RawAccess<>::oop_load(p);
4121 if (!oopDesc::is_oop_or_null(obj)) {
4122 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4123 Universe::print_on(tty);
4124 guarantee(false, "boom");
4125 }
4126 }
4127 public:
4128 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4129 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4130 };
4131
4132 void InstanceKlass::verify_on(outputStream* st) {
4133 #ifndef PRODUCT
4134 // Avoid redundant verifies, this really should be in product.
4135 if (_verify_count == Universe::verify_count()) return;
4136 _verify_count = Universe::verify_count();
4137 #endif
4138
4139 // Verify Klass
4140 Klass::verify_on(st);
4141
4142 // Verify that klass is present in ClassLoaderData
4143 guarantee(class_loader_data()->contains_klass(this),
4144 "this class isn't found in class loader data");
4145
4146 // Verify vtables
4147 if (is_linked()) {
4148 // $$$ This used to be done only for m/s collections. Doing it
4149 // always seemed a valid generalization. (DLD -- 6/00)
4150 vtable().verify(st);
4151 }
4152
4153 // Verify first subklass
4154 if (subklass() != nullptr) {
4155 guarantee(subklass()->is_klass(), "should be klass");
4156 }
4157
4158 // Verify siblings
4159 Klass* super = this->super();
4160 Klass* sib = next_sibling();
4161 if (sib != nullptr) {
4162 if (sib == this) {
4163 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4164 }
4165
4166 guarantee(sib->is_klass(), "should be klass");
4167 guarantee(sib->super() == super, "siblings should have same superklass");
4168 }
4169
4170 // Verify local interfaces
4171 if (local_interfaces()) {
4172 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4173 for (int j = 0; j < local_interfaces->length(); j++) {
4174 InstanceKlass* e = local_interfaces->at(j);
4175 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4176 }
4177 }
4178
4179 // Verify transitive interfaces
4180 if (transitive_interfaces() != nullptr) {
4181 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4182 for (int j = 0; j < transitive_interfaces->length(); j++) {
4183 InstanceKlass* e = transitive_interfaces->at(j);
4184 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4185 }
4186 }
4187
4188 // Verify methods
4189 if (methods() != nullptr) {
4190 Array<Method*>* methods = this->methods();
4191 for (int j = 0; j < methods->length(); j++) {
4192 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4193 }
4194 for (int j = 0; j < methods->length() - 1; j++) {
4195 Method* m1 = methods->at(j);
4196 Method* m2 = methods->at(j + 1);
4197 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4198 }
4199 }
4200
4201 // Verify method ordering
4202 if (method_ordering() != nullptr) {
4203 Array<int>* method_ordering = this->method_ordering();
4204 int length = method_ordering->length();
4205 if (JvmtiExport::can_maintain_original_method_order() ||
4206 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4207 guarantee(length == methods()->length(), "invalid method ordering length");
4208 jlong sum = 0;
4209 for (int j = 0; j < length; j++) {
4210 int original_index = method_ordering->at(j);
4211 guarantee(original_index >= 0, "invalid method ordering index");
4212 guarantee(original_index < length, "invalid method ordering index");
4213 sum += original_index;
4214 }
4215 // Verify sum of indices 0,1,...,length-1
4216 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4217 } else {
4218 guarantee(length == 0, "invalid method ordering length");
4219 }
4220 }
4221
4222 // Verify default methods
4223 if (default_methods() != nullptr) {
4224 Array<Method*>* methods = this->default_methods();
4225 for (int j = 0; j < methods->length(); j++) {
4226 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4227 }
4228 for (int j = 0; j < methods->length() - 1; j++) {
4229 Method* m1 = methods->at(j);
4230 Method* m2 = methods->at(j + 1);
4231 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4232 }
4233 }
4234
4235 // Verify JNI static field identifiers
4236 if (jni_ids() != nullptr) {
4237 jni_ids()->verify(this);
4238 }
4239
4240 // Verify other fields
4241 if (constants() != nullptr) {
4242 guarantee(constants()->is_constantPool(), "should be constant pool");
4243 }
4244 }
4245
4246 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4247 Klass::oop_verify_on(obj, st);
4248 VerifyFieldClosure blk;
4249 obj->oop_iterate(&blk);
4250 }
4251
4252
4253 // JNIid class for jfieldIDs only
4254 // Note to reviewers:
4255 // These JNI functions are just moved over to column 1 and not changed
4256 // in the compressed oops workspace.
4257 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4258 _holder = holder;
4259 _offset = offset;
4260 _next = next;
4261 debug_only(_is_static_field_id = false;)
4262 }
4263
4264
4265 JNIid* JNIid::find(int offset) {
4266 JNIid* current = this;
4267 while (current != nullptr) {
4268 if (current->offset() == offset) return current;
4269 current = current->next();
4270 }
4271 return nullptr;
4272 }
4273
4274 void JNIid::deallocate(JNIid* current) {
4275 while (current != nullptr) {
4276 JNIid* next = current->next();
4277 delete current;
4278 current = next;
4279 }
4280 }
4281
4282
4283 void JNIid::verify(Klass* holder) {
4284 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4285 int end_field_offset;
4286 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4287
4288 JNIid* current = this;
4289 while (current != nullptr) {
4290 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4291 #ifdef ASSERT
4292 int o = current->offset();
4293 if (current->is_static_field_id()) {
4294 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4295 }
4296 #endif
4297 current = current->next();
4298 }
4299 }
4300
4301 void InstanceKlass::set_init_state(ClassState state) {
4302 #ifdef ASSERT
4303 bool good_state = is_shared() ? (_init_state <= state)
4304 : (_init_state < state);
4305 assert(good_state || state == allocated, "illegal state transition");
4306 #endif
4307 assert(_init_thread == nullptr, "should be cleared before state change");
4308 Atomic::release_store(&_init_state, state);
4309 }
4310
4311 #if INCLUDE_JVMTI
4312
4313 // RedefineClasses() support for previous versions
4314
4315 // Globally, there is at least one previous version of a class to walk
4316 // during class unloading, which is saved because old methods in the class
4317 // are still running. Otherwise the previous version list is cleaned up.
4318 bool InstanceKlass::_should_clean_previous_versions = false;
4319
4320 // Returns true if there are previous versions of a class for class
4321 // unloading only. Also resets the flag to false. purge_previous_version
4322 // will set the flag to true if there are any left, i.e., if there's any
4323 // work to do for next time. This is to avoid the expensive code cache
4324 // walk in CLDG::clean_deallocate_lists().
4325 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4326 bool ret = _should_clean_previous_versions;
4327 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4328 ret ? "true" : "false");
4329 _should_clean_previous_versions = false;
4330 return ret;
4331 }
4332
4333 // This nulls out jmethodIDs for all methods in 'klass'
4334 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4335 // during class unloading.
4336 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4337 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4338 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4339 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4340 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4341 Array<Method*>* method_refs = klass->methods();
4342 for (int k = 0; k < method_refs->length(); k++) {
4343 Method* method = method_refs->at(k);
4344 if (method != nullptr && method->is_obsolete()) {
4345 method->clear_jmethod_id();
4346 }
4347 }
4348 }
4349
4350 // Purge previous versions before adding new previous versions of the class and
4351 // during class unloading.
4352 void InstanceKlass::purge_previous_version_list() {
4353 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4354 assert(has_been_redefined(), "Should only be called for main class");
4355
4356 // Quick exit.
4357 if (previous_versions() == nullptr) {
4358 return;
4359 }
4360
4361 // This klass has previous versions so see what we can cleanup
4362 // while it is safe to do so.
4363
4364 int deleted_count = 0; // leave debugging breadcrumbs
4365 int live_count = 0;
4366 ClassLoaderData* loader_data = class_loader_data();
4367 assert(loader_data != nullptr, "should never be null");
4368
4369 ResourceMark rm;
4370 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4371
4372 // previous versions are linked together through the InstanceKlass
4373 InstanceKlass* pv_node = previous_versions();
4374 InstanceKlass* last = this;
4375 int version = 0;
4376
4377 // check the previous versions list
4378 for (; pv_node != nullptr; ) {
4379
4380 ConstantPool* pvcp = pv_node->constants();
4381 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4382
4383 if (!pvcp->on_stack()) {
4384 // If the constant pool isn't on stack, none of the methods
4385 // are executing. Unlink this previous_version.
4386 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4387 // so will be deallocated during the next phase of class unloading.
4388 log_trace(redefine, class, iklass, purge)
4389 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4390 // Unlink from previous version list.
4391 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4392 InstanceKlass* next = pv_node->previous_versions();
4393 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4394 pv_node->link_previous_versions(nullptr); // point next to null
4395 last->link_previous_versions(next);
4396 // Delete this node directly. Nothing is referring to it and we don't
4397 // want it to increase the counter for metadata to delete in CLDG.
4398 MetadataFactory::free_metadata(loader_data, pv_node);
4399 pv_node = next;
4400 deleted_count++;
4401 version++;
4402 continue;
4403 } else {
4404 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4405 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4406 live_count++;
4407 if (pvcp->is_shared()) {
4408 // Shared previous versions can never be removed so no cleaning is needed.
4409 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4410 } else {
4411 // Previous version alive, set that clean is needed for next time.
4412 _should_clean_previous_versions = true;
4413 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4414 }
4415 }
4416
4417 // next previous version
4418 last = pv_node;
4419 pv_node = pv_node->previous_versions();
4420 version++;
4421 }
4422 log_trace(redefine, class, iklass, purge)
4423 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4424 }
4425
4426 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4427 int emcp_method_count) {
4428 int obsolete_method_count = old_methods->length() - emcp_method_count;
4429
4430 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4431 _previous_versions != nullptr) {
4432 // We have a mix of obsolete and EMCP methods so we have to
4433 // clear out any matching EMCP method entries the hard way.
4434 int local_count = 0;
4435 for (int i = 0; i < old_methods->length(); i++) {
4436 Method* old_method = old_methods->at(i);
4437 if (old_method->is_obsolete()) {
4438 // only obsolete methods are interesting
4439 Symbol* m_name = old_method->name();
4440 Symbol* m_signature = old_method->signature();
4441
4442 // previous versions are linked together through the InstanceKlass
4443 int j = 0;
4444 for (InstanceKlass* prev_version = _previous_versions;
4445 prev_version != nullptr;
4446 prev_version = prev_version->previous_versions(), j++) {
4447
4448 Array<Method*>* method_refs = prev_version->methods();
4449 for (int k = 0; k < method_refs->length(); k++) {
4450 Method* method = method_refs->at(k);
4451
4452 if (!method->is_obsolete() &&
4453 method->name() == m_name &&
4454 method->signature() == m_signature) {
4455 // The current RedefineClasses() call has made all EMCP
4456 // versions of this method obsolete so mark it as obsolete
4457 log_trace(redefine, class, iklass, add)
4458 ("%s(%s): flush obsolete method @%d in version @%d",
4459 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4460
4461 method->set_is_obsolete();
4462 break;
4463 }
4464 }
4465
4466 // The previous loop may not find a matching EMCP method, but
4467 // that doesn't mean that we can optimize and not go any
4468 // further back in the PreviousVersion generations. The EMCP
4469 // method for this generation could have already been made obsolete,
4470 // but there still may be an older EMCP method that has not
4471 // been made obsolete.
4472 }
4473
4474 if (++local_count >= obsolete_method_count) {
4475 // no more obsolete methods so bail out now
4476 break;
4477 }
4478 }
4479 }
4480 }
4481 }
4482
4483 // Save the scratch_class as the previous version if any of the methods are running.
4484 // The previous_versions are used to set breakpoints in EMCP methods and they are
4485 // also used to clean MethodData links to redefined methods that are no longer running.
4486 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4487 int emcp_method_count) {
4488 assert(Thread::current()->is_VM_thread(),
4489 "only VMThread can add previous versions");
4490
4491 ResourceMark rm;
4492 log_trace(redefine, class, iklass, add)
4493 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4494
4495 // Clean out old previous versions for this class
4496 purge_previous_version_list();
4497
4498 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4499 // a previous redefinition may be made obsolete by this redefinition.
4500 Array<Method*>* old_methods = scratch_class->methods();
4501 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4502
4503 // If the constant pool for this previous version of the class
4504 // is not marked as being on the stack, then none of the methods
4505 // in this previous version of the class are on the stack so
4506 // we don't need to add this as a previous version.
4507 ConstantPool* cp_ref = scratch_class->constants();
4508 if (!cp_ref->on_stack()) {
4509 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4510 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4511 return;
4512 }
4513
4514 // Add previous version if any methods are still running or if this is
4515 // a shared class which should never be removed.
4516 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4517 scratch_class->link_previous_versions(previous_versions());
4518 link_previous_versions(scratch_class);
4519 if (cp_ref->is_shared()) {
4520 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4521 } else {
4522 // We only set clean_previous_versions flag for processing during class
4523 // unloading for non-shared classes.
4524 _should_clean_previous_versions = true;
4525 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4526 }
4527 } // end add_previous_version()
4528
4529 #endif // INCLUDE_JVMTI
4530
4531 Method* InstanceKlass::method_with_idnum(int idnum) {
4532 Method* m = nullptr;
4533 if (idnum < methods()->length()) {
4534 m = methods()->at(idnum);
4535 }
4536 if (m == nullptr || m->method_idnum() != idnum) {
4537 for (int index = 0; index < methods()->length(); ++index) {
4538 m = methods()->at(index);
4539 if (m->method_idnum() == idnum) {
4540 return m;
4541 }
4542 }
4543 // None found, return null for the caller to handle.
4544 return nullptr;
4545 }
4546 return m;
4547 }
4548
4549
4550 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4551 if (idnum >= methods()->length()) {
4552 return nullptr;
4553 }
4554 Method* m = methods()->at(idnum);
4555 if (m != nullptr && m->orig_method_idnum() == idnum) {
4556 return m;
4557 }
4558 // Obsolete method idnum does not match the original idnum
4559 for (int index = 0; index < methods()->length(); ++index) {
4560 m = methods()->at(index);
4561 if (m->orig_method_idnum() == idnum) {
4562 return m;
4563 }
4564 }
4565 // None found, return null for the caller to handle.
4566 return nullptr;
4567 }
4568
4569
4570 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4571 InstanceKlass* holder = get_klass_version(version);
4572 if (holder == nullptr) {
4573 return nullptr; // The version of klass is gone, no method is found
4574 }
4575 Method* method = holder->method_with_orig_idnum(idnum);
4576 return method;
4577 }
4578
4579 #if INCLUDE_JVMTI
4580 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4581 return _cached_class_file;
4582 }
4583
4584 jint InstanceKlass::get_cached_class_file_len() {
4585 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4586 }
4587
4588 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4589 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4590 }
4591 #endif
4592
4593 // Make a step iterating over the class hierarchy under the root class.
4594 // Skips subclasses if requested.
4595 void ClassHierarchyIterator::next() {
4596 assert(_current != nullptr, "required");
4597 if (_visit_subclasses && _current->subklass() != nullptr) {
4598 _current = _current->subklass();
4599 return; // visit next subclass
4600 }
4601 _visit_subclasses = true; // reset
4602 while (_current->next_sibling() == nullptr && _current != _root) {
4603 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4604 }
4605 if (_current == _root) {
4606 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4607 _current = nullptr;
4608 return;
4609 }
4610 _current = _current->next_sibling();
4611 return; // visit next sibling subclass
4612 }