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 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
443 const int size = InstanceKlass::size(parser.vtable_size(),
444 parser.itable_size(),
445 nonstatic_oop_map_size(parser.total_oop_map_count()),
446 parser.is_interface());
447
448 const Symbol* const class_name = parser.class_name();
449 assert(class_name != nullptr, "invariant");
450 ClassLoaderData* loader_data = parser.loader_data();
451 assert(loader_data != nullptr, "invariant");
452
453 InstanceKlass* ik;
454
455 // Allocation
456 if (parser.is_instance_ref_klass()) {
457 // java.lang.ref.Reference
458 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
459 } else if (class_name == vmSymbols::java_lang_Class()) {
460 // mirror - java.lang.Class
461 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
462 } else if (is_stack_chunk_class(class_name, loader_data)) {
463 // stack chunk
464 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
465 } else if (is_class_loader(class_name, parser)) {
466 // class loader - java.lang.ClassLoader
467 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
468 } else {
469 // normal
470 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
471 }
472
473 // Check for pending exception before adding to the loader data and incrementing
474 // class count. Can get OOM here.
475 if (HAS_PENDING_EXCEPTION) {
476 return nullptr;
477 }
478
479 return ik;
480 }
481
482
483 // copy method ordering from resource area to Metaspace
484 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
485 if (m != nullptr) {
486 // allocate a new array and copy contents (memcpy?)
487 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
488 for (int i = 0; i < m->length(); i++) {
489 _method_ordering->at_put(i, m->at(i));
490 }
491 } else {
492 _method_ordering = Universe::the_empty_int_array();
493 }
494 }
495
496 // create a new array of vtable_indices for default methods
497 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
498 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
499 assert(default_vtable_indices() == nullptr, "only create once");
500 set_default_vtable_indices(vtable_indices);
501 return vtable_indices;
502 }
503
504
505 InstanceKlass::InstanceKlass() {
506 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
507 }
508
509 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
510 Klass(kind),
511 _nest_members(nullptr),
512 _nest_host(nullptr),
513 _permitted_subclasses(nullptr),
514 _record_components(nullptr),
515 _static_field_size(parser.static_field_size()),
516 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
517 _itable_len(parser.itable_size()),
518 _nest_host_index(0),
519 _init_state(allocated),
520 _reference_type(reference_type),
521 _init_thread(nullptr)
522 {
523 set_vtable_length(parser.vtable_size());
524 set_access_flags(parser.access_flags());
525 if (parser.is_hidden()) set_is_hidden();
526 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
527 false));
528
529 assert(nullptr == _methods, "underlying memory not zeroed?");
530 assert(is_instance_klass(), "is layout incorrect?");
531 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
532 }
533
534 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
535 Array<Method*>* methods) {
536 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
537 !methods->is_shared()) {
538 for (int i = 0; i < methods->length(); i++) {
539 Method* method = methods->at(i);
540 if (method == nullptr) continue; // maybe null if error processing
541 // Only want to delete methods that are not executing for RedefineClasses.
542 // The previous version will point to them so they're not totally dangling
543 assert (!method->on_stack(), "shouldn't be called with methods on stack");
544 MetadataFactory::free_metadata(loader_data, method);
545 }
546 MetadataFactory::free_array<Method*>(loader_data, methods);
547 }
548 }
549
550 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
551 const Klass* super_klass,
552 Array<InstanceKlass*>* local_interfaces,
553 Array<InstanceKlass*>* transitive_interfaces) {
554 // Only deallocate transitive interfaces if not empty, same as super class
555 // or same as local interfaces. See code in parseClassFile.
556 Array<InstanceKlass*>* ti = transitive_interfaces;
557 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
558 // check that the interfaces don't come from super class
559 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
560 InstanceKlass::cast(super_klass)->transitive_interfaces();
561 if (ti != sti && ti != nullptr && !ti->is_shared()) {
562 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
563 }
564 }
565
566 // local interfaces can be empty
567 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
568 local_interfaces != nullptr && !local_interfaces->is_shared()) {
569 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
570 }
571 }
572
573 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
574 Array<RecordComponent*>* record_components) {
575 if (record_components != nullptr && !record_components->is_shared()) {
576 for (int i = 0; i < record_components->length(); i++) {
577 RecordComponent* record_component = record_components->at(i);
578 MetadataFactory::free_metadata(loader_data, record_component);
579 }
580 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
581 }
582 }
583
584 // This function deallocates the metadata and C heap pointers that the
585 // InstanceKlass points to.
586 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
587 // Orphan the mirror first, CMS thinks it's still live.
588 if (java_mirror() != nullptr) {
589 java_lang_Class::set_klass(java_mirror(), nullptr);
590 }
591
592 // Also remove mirror from handles
593 loader_data->remove_handle(_java_mirror);
594
595 // Need to take this class off the class loader data list.
596 loader_data->remove_class(this);
597
598 // The array_klass for this class is created later, after error handling.
599 // For class redefinition, we keep the original class so this scratch class
600 // doesn't have an array class. Either way, assert that there is nothing
601 // to deallocate.
602 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
603
604 // Release C heap allocated data that this points to, which includes
605 // reference counting symbol names.
606 // Can't release the constant pool or MethodData C heap data here because the constant
607 // pool can be deallocated separately from the InstanceKlass for default methods and
608 // redefine classes. MethodData can also be released separately.
609 release_C_heap_structures(/* release_sub_metadata */ false);
610
611 deallocate_methods(loader_data, methods());
612 set_methods(nullptr);
613
614 deallocate_record_components(loader_data, record_components());
615 set_record_components(nullptr);
616
617 if (method_ordering() != nullptr &&
618 method_ordering() != Universe::the_empty_int_array() &&
619 !method_ordering()->is_shared()) {
620 MetadataFactory::free_array<int>(loader_data, method_ordering());
621 }
622 set_method_ordering(nullptr);
623
624 // default methods can be empty
625 if (default_methods() != nullptr &&
626 default_methods() != Universe::the_empty_method_array() &&
627 !default_methods()->is_shared()) {
628 MetadataFactory::free_array<Method*>(loader_data, default_methods());
629 }
630 // Do NOT deallocate the default methods, they are owned by superinterfaces.
631 set_default_methods(nullptr);
632
633 // default methods vtable indices can be empty
634 if (default_vtable_indices() != nullptr &&
635 !default_vtable_indices()->is_shared()) {
636 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
637 }
638 set_default_vtable_indices(nullptr);
639
640
641 // This array is in Klass, but remove it with the InstanceKlass since
642 // this place would be the only caller and it can share memory with transitive
643 // interfaces.
644 if (secondary_supers() != nullptr &&
645 secondary_supers() != Universe::the_empty_klass_array() &&
646 // see comments in compute_secondary_supers about the following cast
647 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
648 !secondary_supers()->is_shared()) {
649 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
650 }
651 set_secondary_supers(nullptr);
652
653 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
654 set_transitive_interfaces(nullptr);
655 set_local_interfaces(nullptr);
656
657 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
658 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
659 }
660 set_fieldinfo_stream(nullptr);
661
662 if (fields_status() != nullptr && !fields_status()->is_shared()) {
663 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
664 }
665 set_fields_status(nullptr);
666
667 // If a method from a redefined class is using this constant pool, don't
668 // delete it, yet. The new class's previous version will point to this.
669 if (constants() != nullptr) {
670 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
671 if (!constants()->is_shared()) {
672 MetadataFactory::free_metadata(loader_data, constants());
673 }
674 // Delete any cached resolution errors for the constant pool
675 SystemDictionary::delete_resolution_error(constants());
676
677 set_constants(nullptr);
678 }
679
680 if (inner_classes() != nullptr &&
681 inner_classes() != Universe::the_empty_short_array() &&
682 !inner_classes()->is_shared()) {
683 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
684 }
685 set_inner_classes(nullptr);
686
687 if (nest_members() != nullptr &&
688 nest_members() != Universe::the_empty_short_array() &&
689 !nest_members()->is_shared()) {
690 MetadataFactory::free_array<jushort>(loader_data, nest_members());
691 }
692 set_nest_members(nullptr);
693
694 if (permitted_subclasses() != nullptr &&
695 permitted_subclasses() != Universe::the_empty_short_array() &&
696 !permitted_subclasses()->is_shared()) {
697 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
698 }
699 set_permitted_subclasses(nullptr);
700
701 // We should deallocate the Annotations instance if it's not in shared spaces.
702 if (annotations() != nullptr && !annotations()->is_shared()) {
703 MetadataFactory::free_metadata(loader_data, annotations());
704 }
705 set_annotations(nullptr);
706
707 SystemDictionaryShared::handle_class_unloading(this);
708
709 #if INCLUDE_CDS_JAVA_HEAP
710 if (CDSConfig::is_dumping_heap()) {
711 HeapShared::remove_scratch_objects(this);
712 }
713 #endif
714 }
715
716 bool InstanceKlass::is_record() const {
717 return _record_components != nullptr &&
718 is_final() &&
719 java_super() == vmClasses::Record_klass();
720 }
721
722 bool InstanceKlass::is_sealed() const {
723 return _permitted_subclasses != nullptr &&
724 _permitted_subclasses != Universe::the_empty_short_array();
725 }
726
727 bool InstanceKlass::should_be_initialized() const {
728 return !is_initialized();
729 }
730
731 klassItable InstanceKlass::itable() const {
732 return klassItable(const_cast<InstanceKlass*>(this));
733 }
734
735 // JVMTI spec thinks there are signers and protection domain in the
736 // instanceKlass. These accessors pretend these fields are there.
737 // The hprof specification also thinks these fields are in InstanceKlass.
738 oop InstanceKlass::protection_domain() const {
739 // return the protection_domain from the mirror
740 return java_lang_Class::protection_domain(java_mirror());
741 }
742
743 objArrayOop InstanceKlass::signers() const {
744 // return the signers from the mirror
745 return java_lang_Class::signers(java_mirror());
746 }
747
748 oop InstanceKlass::init_lock() const {
749 // return the init lock from the mirror
750 oop lock = java_lang_Class::init_lock(java_mirror());
751 // Prevent reordering with any access of initialization state
752 OrderAccess::loadload();
753 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
754 "only fully initialized state can have a null lock");
755 return lock;
756 }
757
758 // Set the initialization lock to null so the object can be GC'ed. Any racing
759 // threads to get this lock will see a null lock and will not lock.
760 // That's okay because they all check for initialized state after getting
761 // the lock and return.
762 void InstanceKlass::fence_and_clear_init_lock() {
763 // make sure previous stores are all done, notably the init_state.
764 OrderAccess::storestore();
765 java_lang_Class::clear_init_lock(java_mirror());
766 assert(!is_not_initialized(), "class must be initialized now");
767 }
768
769
770 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
771 // process. The step comments refers to the procedure described in that section.
772 // Note: implementation moved to static method to expose the this pointer.
773 void InstanceKlass::initialize(TRAPS) {
774 if (this->should_be_initialized()) {
775 initialize_impl(CHECK);
776 // Note: at this point the class may be initialized
777 // OR it may be in the state of being initialized
778 // in case of recursive initialization!
779 } else {
780 assert(is_initialized(), "sanity check");
781 }
782 }
783
784 static bool are_super_types_initialized(InstanceKlass* ik) {
785 InstanceKlass* s = ik->java_super();
786 if (s != nullptr && !s->is_initialized()) {
787 return false;
788 }
789
790 if (ik->has_nonstatic_concrete_methods()) {
791 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
792 // having a superinterface that declares, non-static, concrete methods
793 Array<InstanceKlass*>* interfaces = ik->local_interfaces();
794 int len = interfaces->length();
795 for (int i = 0; i < len; i++) {
796 InstanceKlass* intf = interfaces->at(i);
797 if (!intf->is_initialized()) {
798 return false;
799 }
800 }
801 }
802
803 return true;
804 }
805
806 static void log_class_init_start(outputStream* st, JavaThread* current, InstanceKlass* ik, int init_id) {
807 ResourceMark rm;
808 const char* info = "";
809 if (ik->has_preinitialized_mirror() && CDSConfig::is_loading_heap()) {
810 info = " (preinitialized)";
811 } else if (ik->class_initializer() == nullptr) {
812 info = " (no method)";
813 }
814 st->print("%d Initializing ", init_id);
815 ik->name()->print_value_on(st);
816 st->print_cr("%s (" PTR_FORMAT ") by thread " PTR_FORMAT " \"%s\"", info, p2i(ik), p2i(current), current->name());
817 }
818
819 static int log_class_init(JavaThread* current, InstanceKlass* ik) {
820 int init_id = -1;
821 LogStreamHandle(Info, init, class) lsh1;
822 LogStreamHandle(Debug, init) lsh2;
823 if (lsh1.is_enabled() || lsh2.is_enabled()) {
824 static int call_class_initializer_counter = 0; // for debugging
825 init_id = Atomic::fetch_then_add(&call_class_initializer_counter, 1);
826 if (lsh1.is_enabled()) {
827 log_class_init_start(&lsh1, current, ik, init_id);
828 }
829 if (lsh2.is_enabled() && ik->class_initializer() != nullptr && !ik->has_preinitialized_mirror()) {
830 log_class_init_start(&lsh2, current, ik, init_id);
831 }
832 }
833 return init_id;
834 }
835
836 void InstanceKlass::initialize_from_cds(TRAPS) {
837 if (is_initialized()) {
838 return;
839 }
840
841 if (has_preinitialized_mirror() && CDSConfig::is_loading_heap() &&
842 !ForceProfiling &&
843 !RecordTraining &&
844 are_super_types_initialized(this)) {
845 // FIXME: also check for events listeners such as JVMTI, JFR, etc
846 if (log_is_enabled(Info, cds, init)) {
847 ResourceMark rm;
848 log_info(cds, init)("%s (quickest)", external_name());
849 }
850
851 link_class(CHECK);
852
853 #ifdef AZZERT
854 {
855 MonitorLocker ml(THREAD, _init_monitor);
856 assert(!initialized(), "sanity");
857 assert(!is_being_initialized(), "sanity");
858 assert(!is_in_error_state(), "sanity");
859 }
860 #endif
861
862 log_class_init(THREAD, this);
863 set_init_thread(THREAD);
864 set_initialization_state_and_notify(fully_initialized, CHECK);
865 return;
866 }
867
868 if (log_is_enabled(Info, cds, init)) {
869 ResourceMark rm;
870 log_info(cds, init)("%s%s", external_name(),
871 (has_preinitialized_mirror() && CDSConfig::is_loading_heap()) ? " (quicker)" : "");
872 }
873 initialize(THREAD);
874 }
875
876 bool InstanceKlass::verify_code(TRAPS) {
877 // 1) Verify the bytecodes
878 return Verifier::verify(this, should_verify_class(), THREAD);
879 }
880
881 void InstanceKlass::link_class(TRAPS) {
882 assert(is_loaded(), "must be loaded");
883 if (!is_linked()) {
884 link_class_impl(CHECK);
885 }
886 }
887
888 // Called to verify that a class can link during initialization, without
889 // throwing a VerifyError.
890 bool InstanceKlass::link_class_or_fail(TRAPS) {
891 assert(is_loaded(), "must be loaded");
892 if (!is_linked()) {
893 link_class_impl(CHECK_false);
894 }
895 return is_linked();
896 }
897
898 bool InstanceKlass::link_class_impl(TRAPS) {
899 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
900 // This is for CDS static dump only -- we use the in_error_state to indicate that
901 // the class has failed verification. Throwing the NoClassDefFoundError here is just
902 // a convenient way to stop repeat attempts to verify the same (bad) class.
903 //
904 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
905 // if we are executing Java code. This is not a problem for CDS dumping phase since
906 // it doesn't execute any Java code.
907 ResourceMark rm(THREAD);
908 Exceptions::fthrow(THREAD_AND_LOCATION,
909 vmSymbols::java_lang_NoClassDefFoundError(),
910 "Class %s, or one of its supertypes, failed class initialization",
911 external_name());
912 return false;
913 }
914 // return if already verified
915 if (is_linked()) {
916 return true;
917 }
918
919 // Timing
920 // timer handles recursion
921 JavaThread* jt = THREAD;
922
923 // link super class before linking this class
924 Klass* super_klass = super();
925 if (super_klass != nullptr) {
926 if (super_klass->is_interface()) { // check if super class is an interface
927 ResourceMark rm(THREAD);
928 Exceptions::fthrow(
929 THREAD_AND_LOCATION,
930 vmSymbols::java_lang_IncompatibleClassChangeError(),
931 "class %s has interface %s as super class",
932 external_name(),
933 super_klass->external_name()
934 );
935 return false;
936 }
937
938 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
939 ik_super->link_class_impl(CHECK_false);
940 }
941
942 // link all interfaces implemented by this class before linking this class
943 Array<InstanceKlass*>* interfaces = local_interfaces();
944 int num_interfaces = interfaces->length();
945 for (int index = 0; index < num_interfaces; index++) {
946 InstanceKlass* interk = interfaces->at(index);
947 interk->link_class_impl(CHECK_false);
948 }
949
950 // in case the class is linked in the process of linking its superclasses
951 if (is_linked()) {
952 return true;
953 }
954
955 // trace only the link time for this klass that includes
956 // the verification time
957 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
958 ClassLoader::perf_class_link_selftime(),
959 ClassLoader::perf_classes_linked(),
960 jt->get_thread_stat()->perf_recursion_counts_addr(),
961 jt->get_thread_stat()->perf_timers_addr(),
962 PerfClassTraceTime::CLASS_LINK);
963
964 // verification & rewriting
965 {
966 HandleMark hm(THREAD);
967 Handle h_init_lock(THREAD, init_lock());
968 ObjectLocker ol(h_init_lock, jt);
969 // rewritten will have been set if loader constraint error found
970 // on an earlier link attempt
971 // don't verify or rewrite if already rewritten
972 //
973
974 if (!is_linked()) {
975 if (!is_rewritten()) {
976 if (is_shared()) {
977 assert(!verified_at_dump_time(), "must be");
978 }
979 {
980 bool verify_ok = verify_code(THREAD);
981 if (!verify_ok) {
982 return false;
983 }
984 }
985
986 // Just in case a side-effect of verify linked this class already
987 // (which can sometimes happen since the verifier loads classes
988 // using custom class loaders, which are free to initialize things)
989 if (is_linked()) {
990 return true;
991 }
992
993 // also sets rewritten
994 rewrite_class(CHECK_false);
995 } else if (is_shared()) {
996 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
997 }
998
999 // relocate jsrs and link methods after they are all rewritten
1000 link_methods(CHECK_false);
1001
1002 // Initialize the vtable and interface table after
1003 // methods have been rewritten since rewrite may
1004 // fabricate new Method*s.
1005 // also does loader constraint checking
1006 //
1007 // initialize_vtable and initialize_itable need to be rerun
1008 // for a shared class if
1009 // 1) the class is loaded by custom class loader or
1010 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1011 // 3) the class was not verified during dump time
1012 bool need_init_table = true;
1013 if (is_shared() && verified_at_dump_time() &&
1014 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1015 need_init_table = false;
1016 }
1017 if (need_init_table) {
1018 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1019 itable().initialize_itable_and_check_constraints(CHECK_false);
1020 }
1021 #ifdef ASSERT
1022 vtable().verify(tty, true);
1023 // In case itable verification is ever added.
1024 // itable().verify(tty, true);
1025 #endif
1026 if (Universe::is_fully_initialized()) {
1027 DeoptimizationScope deopt_scope;
1028 {
1029 // Now mark all code that assumes the class is not linked.
1030 // Set state under the Compile_lock also.
1031 MutexLocker ml(THREAD, Compile_lock);
1032
1033 set_init_state(linked);
1034 CodeCache::mark_dependents_on(&deopt_scope, this);
1035 }
1036 // Perform the deopt handshake outside Compile_lock.
1037 deopt_scope.deoptimize_marked();
1038 } else {
1039 set_init_state(linked);
1040 }
1041 if (JvmtiExport::should_post_class_prepare()) {
1042 JvmtiExport::post_class_prepare(THREAD, this);
1043 }
1044 }
1045 }
1046 return true;
1047 }
1048
1049 // Rewrite the byte codes of all of the methods of a class.
1050 // The rewriter must be called exactly once. Rewriting must happen after
1051 // verification but before the first method of the class is executed.
1052 void InstanceKlass::rewrite_class(TRAPS) {
1053 assert(is_loaded(), "must be loaded");
1054 if (is_rewritten()) {
1055 assert(is_shared(), "rewriting an unshared class?");
1056 return;
1057 }
1058 Rewriter::rewrite(this, CHECK);
1059 set_rewritten();
1060 }
1061
1062 // Now relocate and link method entry points after class is rewritten.
1063 // This is outside is_rewritten flag. In case of an exception, it can be
1064 // executed more than once.
1065 void InstanceKlass::link_methods(TRAPS) {
1066 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1067
1068 int len = methods()->length();
1069 for (int i = len-1; i >= 0; i--) {
1070 methodHandle m(THREAD, methods()->at(i));
1071
1072 // Set up method entry points for compiler and interpreter .
1073 m->link_method(m, CHECK);
1074 }
1075 }
1076
1077 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1078 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1079 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1080 for (int i = 0; i < local_interfaces()->length(); ++i) {
1081 InstanceKlass* ik = local_interfaces()->at(i);
1082
1083 // Initialization is depth first search ie. we start with top of the inheritance tree
1084 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1085 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1086 if (ik->has_nonstatic_concrete_methods()) {
1087 ik->initialize_super_interfaces(CHECK);
1088 }
1089
1090 // Only initialize() interfaces that "declare" concrete methods.
1091 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1092 ik->initialize(CHECK);
1093 }
1094 }
1095 }
1096
1097 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1098 static InitializationErrorTable* _initialization_error_table;
1099
1100 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1101 // Create the same exception with a message indicating the thread name,
1102 // and the StackTraceElements.
1103 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1104 ResourceMark rm(current);
1105 if (init_error.is_null()) {
1106 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1107
1108 // We failed to create the new exception, most likely due to either out-of-memory or
1109 // a stackoverflow error. If the original exception was either of those then we save
1110 // the shared, pre-allocated, stackless, instance of that exception.
1111 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1112 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1113 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1114 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1115 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1116 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1117 } else {
1118 return;
1119 }
1120 }
1121
1122 MutexLocker ml(current, ClassInitError_lock);
1123 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1124 bool created;
1125 if (_initialization_error_table == nullptr) {
1126 _initialization_error_table = new (mtClass) InitializationErrorTable();
1127 }
1128 _initialization_error_table->put_if_absent(this, elem, &created);
1129 assert(created, "Initialization is single threaded");
1130 log_trace(class, init)("Initialization error added for class %s", external_name());
1131 }
1132
1133 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1134 MutexLocker ml(current, ClassInitError_lock);
1135 if (_initialization_error_table == nullptr) {
1136 return nullptr;
1137 }
1138 OopHandle* h = _initialization_error_table->get(this);
1139 return (h != nullptr) ? h->resolve() : nullptr;
1140 }
1141
1142 // Need to remove entries for unloaded classes.
1143 void InstanceKlass::clean_initialization_error_table() {
1144 struct InitErrorTableCleaner {
1145 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1146 if (!ik->is_loader_alive()) {
1147 h.release(Universe::vm_global());
1148 return true;
1149 } else {
1150 return false;
1151 }
1152 }
1153 };
1154
1155 assert_locked_or_safepoint(ClassInitError_lock);
1156 InitErrorTableCleaner cleaner;
1157 if (_initialization_error_table != nullptr) {
1158 _initialization_error_table->unlink(&cleaner);
1159 }
1160 }
1161
1162 void InstanceKlass::initialize_impl(TRAPS) {
1163 HandleMark hm(THREAD);
1164
1165 // Make sure klass is linked (verified) before initialization
1166 // A class could already be verified, since it has been reflected upon.
1167 link_class(CHECK);
1168
1169 DTRACE_CLASSINIT_PROBE(required, -1);
1170
1171 bool wait = false;
1172
1173 JavaThread* jt = THREAD;
1174
1175 if (ForceProfiling) {
1176 // Preallocate MDOs.
1177 for (int i = 0; i < methods()->length(); i++) {
1178 assert(!HAS_PENDING_EXCEPTION, "");
1179 methodHandle m(THREAD, methods()->at(i));
1180 Method::build_profiling_method_data(m, THREAD);
1181 if (HAS_PENDING_EXCEPTION) {
1182 ResourceMark rm;
1183 log_warning(cds)("MDO preallocation failed for %s", external_name());
1184 CLEAR_PENDING_EXCEPTION;
1185 break;
1186 }
1187 }
1188 }
1189
1190 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1191
1192 // refer to the JVM book page 47 for description of steps
1193 // Step 1
1194 {
1195 Handle h_init_lock(THREAD, init_lock());
1196 ObjectLocker ol(h_init_lock, jt);
1197
1198 // Step 2
1199 // If we were to use wait() instead of waitInterruptibly() then
1200 // we might end up throwing IE from link/symbol resolution sites
1201 // that aren't expected to throw. This would wreak havoc. See 6320309.
1202 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1203 if (debug_logging_enabled) {
1204 ResourceMark rm(jt);
1205 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1206 jt->name(), external_name(), init_thread_name());
1207 }
1208 wait = true;
1209 jt->set_class_to_be_initialized(this);
1210 ol.wait_uninterruptibly(jt);
1211 jt->set_class_to_be_initialized(nullptr);
1212 }
1213
1214 // Step 3
1215 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1216 if (debug_logging_enabled) {
1217 ResourceMark rm(jt);
1218 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1219 jt->name(), external_name());
1220 }
1221 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1222 return;
1223 }
1224
1225 // Step 4
1226 if (is_initialized()) {
1227 if (debug_logging_enabled) {
1228 ResourceMark rm(jt);
1229 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1230 jt->name(), external_name());
1231 }
1232 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1233 return;
1234 }
1235
1236 // Step 5
1237 if (is_in_error_state()) {
1238 if (debug_logging_enabled) {
1239 ResourceMark rm(jt);
1240 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1241 jt->name(), external_name());
1242 }
1243
1244 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1245 ResourceMark rm(THREAD);
1246 Handle cause(THREAD, get_initialization_error(THREAD));
1247
1248 stringStream ss;
1249 ss.print("Could not initialize class %s", external_name());
1250 if (cause.is_null()) {
1251 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1252 } else {
1253 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1254 ss.as_string(), cause);
1255 }
1256 } else {
1257
1258 // Step 6
1259 set_init_state(being_initialized);
1260 set_init_thread(jt);
1261 if (debug_logging_enabled) {
1262 ResourceMark rm(jt);
1263 log_debug(class, init)("Thread \"%s\" is initializing %s",
1264 jt->name(), external_name());
1265 }
1266 }
1267 }
1268
1269 // Step 7
1270 // Next, if C is a class rather than an interface, initialize it's super class and super
1271 // interfaces.
1272 if (!is_interface()) {
1273 Klass* super_klass = super();
1274 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1275 super_klass->initialize(THREAD);
1276 }
1277 // If C implements any interface that declares a non-static, concrete method,
1278 // the initialization of C triggers initialization of its super interfaces.
1279 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1280 // having a superinterface that declares, non-static, concrete methods
1281 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1282 initialize_super_interfaces(THREAD);
1283 }
1284
1285 // If any exceptions, complete abruptly, throwing the same exception as above.
1286 if (HAS_PENDING_EXCEPTION) {
1287 Handle e(THREAD, PENDING_EXCEPTION);
1288 CLEAR_PENDING_EXCEPTION;
1289 {
1290 EXCEPTION_MARK;
1291 add_initialization_error(THREAD, e);
1292 // Locks object, set state, and notify all waiting threads
1293 set_initialization_state_and_notify(initialization_error, THREAD);
1294 CLEAR_PENDING_EXCEPTION;
1295 }
1296 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1297 THROW_OOP(e());
1298 }
1299 }
1300
1301
1302 // Step 8
1303 {
1304 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1305 if (class_initializer() != nullptr) {
1306 // Timer includes any side effects of class initialization (resolution,
1307 // etc), but not recursive entry into call_class_initializer().
1308 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1309 ClassLoader::perf_class_init_selftime(),
1310 ClassLoader::perf_classes_inited(),
1311 jt->get_thread_stat()->perf_recursion_counts_addr(),
1312 jt->get_thread_stat()->perf_timers_addr(),
1313 PerfClassTraceTime::CLASS_CLINIT);
1314 call_class_initializer(THREAD);
1315 } else {
1316 // The elapsed time is so small it's not worth counting.
1317 if (UsePerfData) {
1318 ClassLoader::perf_classes_inited()->inc();
1319 }
1320 call_class_initializer(THREAD);
1321 }
1322 }
1323
1324 // Step 9
1325 if (!HAS_PENDING_EXCEPTION) {
1326 set_initialization_state_and_notify(fully_initialized, CHECK);
1327 debug_only(vtable().verify(tty, true);)
1328 CompilationPolicy::replay_training_at_init(this, THREAD);
1329 }
1330 else {
1331 // Step 10 and 11
1332 Handle e(THREAD, PENDING_EXCEPTION);
1333 CLEAR_PENDING_EXCEPTION;
1334 // JVMTI has already reported the pending exception
1335 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1336 JvmtiExport::clear_detected_exception(jt);
1337 {
1338 EXCEPTION_MARK;
1339 add_initialization_error(THREAD, e);
1340 set_initialization_state_and_notify(initialization_error, THREAD);
1341 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1342 // JVMTI has already reported the pending exception
1343 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1344 JvmtiExport::clear_detected_exception(jt);
1345 }
1346 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1347 if (e->is_a(vmClasses::Error_klass())) {
1348 THROW_OOP(e());
1349 } else {
1350 JavaCallArguments args(e);
1351 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1352 vmSymbols::throwable_void_signature(),
1353 &args);
1354 }
1355 }
1356 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1357 }
1358
1359 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1360 Handle h_init_lock(THREAD, init_lock());
1361 if (h_init_lock() != nullptr) {
1362 ObjectLocker ol(h_init_lock, THREAD);
1363 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1364 set_init_state(state);
1365 fence_and_clear_init_lock();
1366 ol.notify_all(CHECK);
1367 } else {
1368 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1369 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1370 set_init_state(state);
1371 }
1372 }
1373
1374 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1375 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1376 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1377 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1378
1379 DeoptimizationScope deopt_scope;
1380 {
1381 MutexLocker ml(current, Compile_lock);
1382
1383 set_init_state(InstanceKlass::loaded);
1384 // make sure init_state store is already done.
1385 // The compiler reads the hierarchy outside of the Compile_lock.
1386 // Access ordering is used to add to hierarchy.
1387
1388 // Link into hierarchy.
1389 append_to_sibling_list(); // add to superklass/sibling list
1390 process_interfaces(); // handle all "implements" declarations
1391
1392 // Now mark all code that depended on old class hierarchy.
1393 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1394 if (Universe::is_fully_initialized()) {
1395 CodeCache::mark_dependents_on(&deopt_scope, this);
1396 }
1397 }
1398 // Perform the deopt handshake outside Compile_lock.
1399 deopt_scope.deoptimize_marked();
1400 }
1401
1402
1403 InstanceKlass* InstanceKlass::implementor() const {
1404 InstanceKlass* volatile* ik = adr_implementor();
1405 if (ik == nullptr) {
1406 return nullptr;
1407 } else {
1408 // This load races with inserts, and therefore needs acquire.
1409 InstanceKlass* ikls = Atomic::load_acquire(ik);
1410 if (ikls != nullptr && !ikls->is_loader_alive()) {
1411 return nullptr; // don't return unloaded class
1412 } else {
1413 return ikls;
1414 }
1415 }
1416 }
1417
1418
1419 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1420 assert_locked_or_safepoint(Compile_lock);
1421 assert(is_interface(), "not interface");
1422 InstanceKlass* volatile* addr = adr_implementor();
1423 assert(addr != nullptr, "null addr");
1424 if (addr != nullptr) {
1425 Atomic::release_store(addr, ik);
1426 }
1427 }
1428
1429 int InstanceKlass::nof_implementors() const {
1430 InstanceKlass* ik = implementor();
1431 if (ik == nullptr) {
1432 return 0;
1433 } else if (ik != this) {
1434 return 1;
1435 } else {
1436 return 2;
1437 }
1438 }
1439
1440 // The embedded _implementor field can only record one implementor.
1441 // When there are more than one implementors, the _implementor field
1442 // is set to the interface Klass* itself. Following are the possible
1443 // values for the _implementor field:
1444 // null - no implementor
1445 // implementor Klass* - one implementor
1446 // self - more than one implementor
1447 //
1448 // The _implementor field only exists for interfaces.
1449 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1450 if (Universe::is_fully_initialized()) {
1451 assert_lock_strong(Compile_lock);
1452 }
1453 assert(is_interface(), "not interface");
1454 // Filter out my subinterfaces.
1455 // (Note: Interfaces are never on the subklass list.)
1456 if (ik->is_interface()) return;
1457
1458 // Filter out subclasses whose supers already implement me.
1459 // (Note: CHA must walk subclasses of direct implementors
1460 // in order to locate indirect implementors.)
1461 InstanceKlass* super_ik = ik->java_super();
1462 if (super_ik != nullptr && super_ik->implements_interface(this))
1463 // We only need to check one immediate superclass, since the
1464 // implements_interface query looks at transitive_interfaces.
1465 // Any supers of the super have the same (or fewer) transitive_interfaces.
1466 return;
1467
1468 InstanceKlass* iklass = implementor();
1469 if (iklass == nullptr) {
1470 set_implementor(ik);
1471 } else if (iklass != this && iklass != ik) {
1472 // There is already an implementor. Use itself as an indicator of
1473 // more than one implementors.
1474 set_implementor(this);
1475 }
1476
1477 // The implementor also implements the transitive_interfaces
1478 for (int index = 0; index < local_interfaces()->length(); index++) {
1479 local_interfaces()->at(index)->add_implementor(ik);
1480 }
1481 }
1482
1483 void InstanceKlass::init_implementor() {
1484 if (is_interface()) {
1485 set_implementor(nullptr);
1486 }
1487 }
1488
1489
1490 void InstanceKlass::process_interfaces() {
1491 // link this class into the implementors list of every interface it implements
1492 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1493 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1494 InstanceKlass* interf = local_interfaces()->at(i);
1495 assert(interf->is_interface(), "expected interface");
1496 interf->add_implementor(this);
1497 }
1498 }
1499
1500 bool InstanceKlass::can_be_primary_super_slow() const {
1501 if (is_interface())
1502 return false;
1503 else
1504 return Klass::can_be_primary_super_slow();
1505 }
1506
1507 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1508 Array<InstanceKlass*>* transitive_interfaces) {
1509 // The secondaries are the implemented interfaces.
1510 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1511 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1512 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1513 int num_secondaries = num_extra_slots + interfaces->length();
1514 if (num_secondaries == 0) {
1515 // Must share this for correct bootstrapping!
1516 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1517 return nullptr;
1518 } else if (num_extra_slots == 0) {
1519 // The secondary super list is exactly the same as the transitive interfaces, so
1520 // let's use it instead of making a copy.
1521 // Redefine classes has to be careful not to delete this!
1522 if (!UseSecondarySupersTable) {
1523 set_secondary_supers(interfaces);
1524 return nullptr;
1525 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1526 // We will reuse the transitive interfaces list if we're certain
1527 // it's in hash order.
1528 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1529 set_secondary_supers(interfaces, bitmap);
1530 return nullptr;
1531 }
1532 // ... fall through if that didn't work.
1533 }
1534 // Copy transitive interfaces to a temporary growable array to be constructed
1535 // into the secondary super list with extra slots.
1536 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1537 for (int i = 0; i < interfaces->length(); i++) {
1538 secondaries->push(interfaces->at(i));
1539 }
1540 return secondaries;
1541 }
1542
1543 bool InstanceKlass::implements_interface(Klass* k) const {
1544 if (this == k) return true;
1545 assert(k->is_interface(), "should be an interface class");
1546 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1547 if (transitive_interfaces()->at(i) == k) {
1548 return true;
1549 }
1550 }
1551 return false;
1552 }
1553
1554 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1555 // Verify direct super interface
1556 if (this == k) return true;
1557 assert(k->is_interface(), "should be an interface class");
1558 for (int i = 0; i < local_interfaces()->length(); i++) {
1559 if (local_interfaces()->at(i) == k) {
1560 return true;
1561 }
1562 }
1563 return false;
1564 }
1565
1566 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1567 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1568 size_t size = objArrayOopDesc::object_size(length);
1569 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1570 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1571 /* do_zero */ true, CHECK_NULL);
1572 return o;
1573 }
1574
1575 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1576 if (TraceFinalizerRegistration) {
1577 tty->print("Registered ");
1578 i->print_value_on(tty);
1579 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1580 }
1581 instanceHandle h_i(THREAD, i);
1582 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1583 JavaValue result(T_VOID);
1584 JavaCallArguments args(h_i);
1585 methodHandle mh(THREAD, Universe::finalizer_register_method());
1586 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1587 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1588 return h_i();
1589 }
1590
1591 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1592 assert(!is_abstract() && !is_interface(), "Should not create this object");
1593 size_t size = size_helper(); // Query before forming handle.
1594 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1595 }
1596
1597 instanceOop InstanceKlass::allocate_instance(oop java_class,
1598 const char* who,
1599 TRAPS) {
1600 Klass* k = java_lang_Class::as_Klass(java_class);
1601 if (k == nullptr) {
1602 ResourceMark rm(THREAD);
1603 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1604 }
1605 InstanceKlass* ik = cast(k);
1606 ik->check_valid_for_instantiation(false, CHECK_NULL);
1607 ik->initialize(CHECK_NULL);
1608 return ik->allocate_instance(THREAD);
1609 }
1610
1611 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1612 return instanceHandle(THREAD, allocate_instance(THREAD));
1613 }
1614
1615 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1616 if (is_interface() || is_abstract()) {
1617 ResourceMark rm(THREAD);
1618 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1619 : vmSymbols::java_lang_InstantiationException(), external_name());
1620 }
1621 if (this == vmClasses::Class_klass()) {
1622 ResourceMark rm(THREAD);
1623 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1624 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1625 }
1626 }
1627
1628 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1629 // Need load-acquire for lock-free read
1630 if (array_klasses_acquire() == nullptr) {
1631
1632 // Recursively lock array allocation
1633 RecursiveLocker rl(MultiArray_lock, THREAD);
1634
1635 // Check if another thread created the array klass while we were waiting for the lock.
1636 if (array_klasses() == nullptr) {
1637 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1638 // use 'release' to pair with lock-free load
1639 release_set_array_klasses(k);
1640 }
1641 }
1642
1643 // array_klasses() will always be set at this point
1644 ObjArrayKlass* ak = array_klasses();
1645 assert(ak != nullptr, "should be set");
1646 return ak->array_klass(n, THREAD);
1647 }
1648
1649 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1650 // Need load-acquire for lock-free read
1651 ObjArrayKlass* oak = array_klasses_acquire();
1652 if (oak == nullptr) {
1653 return nullptr;
1654 } else {
1655 return oak->array_klass_or_null(n);
1656 }
1657 }
1658
1659 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1660 return array_klass(1, THREAD);
1661 }
1662
1663 ArrayKlass* InstanceKlass::array_klass_or_null() {
1664 return array_klass_or_null(1);
1665 }
1666
1667 Method* InstanceKlass::class_initializer() const {
1668 Method* clinit = find_method(
1669 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1670 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1671 return clinit;
1672 }
1673 return nullptr;
1674 }
1675
1676 void InstanceKlass::call_class_initializer(TRAPS) {
1677 if (ReplayCompiles &&
1678 (ReplaySuppressInitializers == 1 ||
1679 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1680 // Hide the existence of the initializer for the purpose of replaying the compile
1681 return;
1682 }
1683
1684 #if INCLUDE_CDS
1685 // This is needed to ensure the consistency of the archived heap objects.
1686 if (has_archived_enum_objs()) {
1687 assert(is_shared(), "must be");
1688 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1689 if (initialized) {
1690 return;
1691 }
1692 } else if (has_preinitialized_mirror() && CDSConfig::is_loading_heap()) {
1693 log_class_init(THREAD, this);
1694 return;
1695 }
1696 #endif
1697
1698 methodHandle h_method(THREAD, class_initializer());
1699 assert(!is_initialized(), "we cannot initialize twice");
1700 int init_id = log_class_init(THREAD, this);
1701 if (h_method() != nullptr) {
1702 JavaCallArguments args; // No arguments
1703 JavaValue result(T_VOID);
1704 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1705 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1706
1707 elapsedTimer timer;
1708 {
1709 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1710 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1711
1712 timer.start();
1713 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1714 timer.stop();
1715 }
1716
1717 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1718
1719 jlong bc_executed = (bc_end - bc_start);
1720 if (UsePerfData && outer == nullptr) { // outermost clinit
1721 THREAD->inc_clinit_bc_counter_value(bc_executed);
1722 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1723 }
1724
1725 THREAD->set_class_being_initialized(outer);
1726
1727 LogStreamHandle(Debug, init) log;
1728 if (log.is_enabled()) {
1729 ResourceMark rm(THREAD);
1730 log.print("%d Initialized in %.3fms (total: %ldms); ",
1731 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1732 if (CountBytecodes || CountBytecodesPerThread) {
1733 log.print("executed %ld bytecodes; ", bc_executed);
1734 }
1735 name()->print_value_on(&log);
1736 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1737 p2i(THREAD), THREAD->name(), p2i(this));
1738 }
1739 }
1740 LogTarget(Info, class, init) lt;
1741 if (lt.is_enabled()) {
1742 ResourceMark rm(THREAD);
1743 LogStream ls(lt);
1744 ls.print("%d Initialized ", init_id);
1745 name()->print_value_on(&ls);
1746 ls.print_cr("%s (" PTR_FORMAT ")", h_method() == nullptr ? "(no method)" : "", p2i(this));
1747 }
1748 }
1749
1750 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1751 InterpreterOopMap* entry_for) {
1752 // Lazily create the _oop_map_cache at first request.
1753 // Load_acquire is needed to safely get instance published with CAS by another thread.
1754 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1755 if (oop_map_cache == nullptr) {
1756 // Try to install new instance atomically.
1757 oop_map_cache = new OopMapCache();
1758 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1759 if (other != nullptr) {
1760 // Someone else managed to install before us, ditch local copy and use the existing one.
1761 delete oop_map_cache;
1762 oop_map_cache = other;
1763 }
1764 }
1765 // _oop_map_cache is constant after init; lookup below does its own locking.
1766 oop_map_cache->lookup(method, bci, entry_for);
1767 }
1768
1769 bool InstanceKlass::contains_field_offset(int offset) {
1770 fieldDescriptor fd;
1771 return find_field_from_offset(offset, false, &fd);
1772 }
1773
1774 FieldInfo InstanceKlass::field(int index) const {
1775 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1776 if (fs.index() == index) {
1777 return fs.to_FieldInfo();
1778 }
1779 }
1780 fatal("Field not found");
1781 return FieldInfo();
1782 }
1783
1784 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1785 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1786 Symbol* f_name = fs.name();
1787 Symbol* f_sig = fs.signature();
1788 if (f_name == name && f_sig == sig) {
1789 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1790 return true;
1791 }
1792 }
1793 return false;
1794 }
1795
1796
1797 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1798 const int n = local_interfaces()->length();
1799 for (int i = 0; i < n; i++) {
1800 Klass* intf1 = local_interfaces()->at(i);
1801 assert(intf1->is_interface(), "just checking type");
1802 // search for field in current interface
1803 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1804 assert(fd->is_static(), "interface field must be static");
1805 return intf1;
1806 }
1807 // search for field in direct superinterfaces
1808 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1809 if (intf2 != nullptr) return intf2;
1810 }
1811 // otherwise field lookup fails
1812 return nullptr;
1813 }
1814
1815
1816 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1817 // search order according to newest JVM spec (5.4.3.2, p.167).
1818 // 1) search for field in current klass
1819 if (find_local_field(name, sig, fd)) {
1820 return const_cast<InstanceKlass*>(this);
1821 }
1822 // 2) search for field recursively in direct superinterfaces
1823 { Klass* intf = find_interface_field(name, sig, fd);
1824 if (intf != nullptr) return intf;
1825 }
1826 // 3) apply field lookup recursively if superclass exists
1827 { Klass* supr = super();
1828 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1829 }
1830 // 4) otherwise field lookup fails
1831 return nullptr;
1832 }
1833
1834
1835 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1836 // search order according to newest JVM spec (5.4.3.2, p.167).
1837 // 1) search for field in current klass
1838 if (find_local_field(name, sig, fd)) {
1839 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1840 }
1841 // 2) search for field recursively in direct superinterfaces
1842 if (is_static) {
1843 Klass* intf = find_interface_field(name, sig, fd);
1844 if (intf != nullptr) return intf;
1845 }
1846 // 3) apply field lookup recursively if superclass exists
1847 { Klass* supr = super();
1848 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1849 }
1850 // 4) otherwise field lookup fails
1851 return nullptr;
1852 }
1853
1854
1855 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1856 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1857 if (fs.offset() == offset) {
1858 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1859 if (fd->is_static() == is_static) return true;
1860 }
1861 }
1862 return false;
1863 }
1864
1865
1866 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1867 Klass* klass = const_cast<InstanceKlass*>(this);
1868 while (klass != nullptr) {
1869 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1870 return true;
1871 }
1872 klass = klass->super();
1873 }
1874 return false;
1875 }
1876
1877
1878 void InstanceKlass::methods_do(void f(Method* method)) {
1879 // Methods aren't stable until they are loaded. This can be read outside
1880 // a lock through the ClassLoaderData for profiling
1881 // Redefined scratch classes are on the list and need to be cleaned
1882 if (!is_loaded() && !is_scratch_class()) {
1883 return;
1884 }
1885
1886 int len = methods()->length();
1887 for (int index = 0; index < len; index++) {
1888 Method* m = methods()->at(index);
1889 assert(m->is_method(), "must be method");
1890 f(m);
1891 }
1892 }
1893
1894
1895 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1896 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1897 if (fs.access_flags().is_static()) {
1898 fieldDescriptor& fd = fs.field_descriptor();
1899 cl->do_field(&fd);
1900 }
1901 }
1902 }
1903
1904
1905 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1906 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1907 if (fs.access_flags().is_static()) {
1908 fieldDescriptor& fd = fs.field_descriptor();
1909 f(&fd, mirror, CHECK);
1910 }
1911 }
1912 }
1913
1914 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1915 InstanceKlass* super = superklass();
1916 if (super != nullptr) {
1917 super->do_nonstatic_fields(cl);
1918 }
1919 fieldDescriptor fd;
1920 int length = java_fields_count();
1921 for (int i = 0; i < length; i += 1) {
1922 fd.reinitialize(this, i);
1923 if (!fd.is_static()) {
1924 cl->do_field(&fd);
1925 }
1926 }
1927 }
1928
1929 // first in Pair is offset, second is index.
1930 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1931 return a->first - b->first;
1932 }
1933
1934 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1935 InstanceKlass* super = superklass();
1936 if (super != nullptr) {
1937 super->print_nonstatic_fields(cl);
1938 }
1939 ResourceMark rm;
1940 fieldDescriptor fd;
1941 // In DebugInfo nonstatic fields are sorted by offset.
1942 GrowableArray<Pair<int,int> > fields_sorted;
1943 int i = 0;
1944 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1945 if (!fs.access_flags().is_static()) {
1946 fd = fs.field_descriptor();
1947 Pair<int,int> f(fs.offset(), fs.index());
1948 fields_sorted.push(f);
1949 i++;
1950 }
1951 }
1952 if (i > 0) {
1953 int length = i;
1954 assert(length == fields_sorted.length(), "duh");
1955 fields_sorted.sort(compare_fields_by_offset);
1956 for (int i = 0; i < length; i++) {
1957 fd.reinitialize(this, fields_sorted.at(i).second);
1958 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1959 cl->do_field(&fd);
1960 }
1961 }
1962 }
1963
1964 #ifdef ASSERT
1965 static int linear_search(const Array<Method*>* methods,
1966 const Symbol* name,
1967 const Symbol* signature) {
1968 const int len = methods->length();
1969 for (int index = 0; index < len; index++) {
1970 const Method* const m = methods->at(index);
1971 assert(m->is_method(), "must be method");
1972 if (m->signature() == signature && m->name() == name) {
1973 return index;
1974 }
1975 }
1976 return -1;
1977 }
1978 #endif
1979
1980 bool InstanceKlass::_disable_method_binary_search = false;
1981
1982 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1983 int len = methods->length();
1984 int l = 0;
1985 int h = len - 1;
1986 while (l <= h) {
1987 Method* m = methods->at(l);
1988 if (m->name() == name) {
1989 return l;
1990 }
1991 l++;
1992 }
1993 return -1;
1994 }
1995
1996 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1997 if (_disable_method_binary_search) {
1998 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
1999 // At the final stage of dynamic dumping, the methods array may not be sorted
2000 // by ascending addresses of their names, so we can't use binary search anymore.
2001 // However, methods with the same name are still laid out consecutively inside the
2002 // methods array, so let's look for the first one that matches.
2003 return linear_search(methods, name);
2004 }
2005
2006 int len = methods->length();
2007 int l = 0;
2008 int h = len - 1;
2009
2010 // methods are sorted by ascending addresses of their names, so do binary search
2011 while (l <= h) {
2012 int mid = (l + h) >> 1;
2013 Method* m = methods->at(mid);
2014 assert(m->is_method(), "must be method");
2015 int res = m->name()->fast_compare(name);
2016 if (res == 0) {
2017 return mid;
2018 } else if (res < 0) {
2019 l = mid + 1;
2020 } else {
2021 h = mid - 1;
2022 }
2023 }
2024 return -1;
2025 }
2026
2027 // find_method looks up the name/signature in the local methods array
2028 Method* InstanceKlass::find_method(const Symbol* name,
2029 const Symbol* signature) const {
2030 return find_method_impl(name, signature,
2031 OverpassLookupMode::find,
2032 StaticLookupMode::find,
2033 PrivateLookupMode::find);
2034 }
2035
2036 Method* InstanceKlass::find_method_impl(const Symbol* name,
2037 const Symbol* signature,
2038 OverpassLookupMode overpass_mode,
2039 StaticLookupMode static_mode,
2040 PrivateLookupMode private_mode) const {
2041 return InstanceKlass::find_method_impl(methods(),
2042 name,
2043 signature,
2044 overpass_mode,
2045 static_mode,
2046 private_mode);
2047 }
2048
2049 // find_instance_method looks up the name/signature in the local methods array
2050 // and skips over static methods
2051 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2052 const Symbol* name,
2053 const Symbol* signature,
2054 PrivateLookupMode private_mode) {
2055 Method* const meth = InstanceKlass::find_method_impl(methods,
2056 name,
2057 signature,
2058 OverpassLookupMode::find,
2059 StaticLookupMode::skip,
2060 private_mode);
2061 assert(((meth == nullptr) || !meth->is_static()),
2062 "find_instance_method should have skipped statics");
2063 return meth;
2064 }
2065
2066 // find_instance_method looks up the name/signature in the local methods array
2067 // and skips over static methods
2068 Method* InstanceKlass::find_instance_method(const Symbol* name,
2069 const Symbol* signature,
2070 PrivateLookupMode private_mode) const {
2071 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2072 }
2073
2074 // Find looks up the name/signature in the local methods array
2075 // and filters on the overpass, static and private flags
2076 // This returns the first one found
2077 // note that the local methods array can have up to one overpass, one static
2078 // and one instance (private or not) with the same name/signature
2079 Method* InstanceKlass::find_local_method(const Symbol* name,
2080 const Symbol* signature,
2081 OverpassLookupMode overpass_mode,
2082 StaticLookupMode static_mode,
2083 PrivateLookupMode private_mode) const {
2084 return InstanceKlass::find_method_impl(methods(),
2085 name,
2086 signature,
2087 overpass_mode,
2088 static_mode,
2089 private_mode);
2090 }
2091
2092 // Find looks up the name/signature in the local methods array
2093 // and filters on the overpass, static and private flags
2094 // This returns the first one found
2095 // note that the local methods array can have up to one overpass, one static
2096 // and one instance (private or not) with the same name/signature
2097 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2098 const Symbol* name,
2099 const Symbol* signature,
2100 OverpassLookupMode overpass_mode,
2101 StaticLookupMode static_mode,
2102 PrivateLookupMode private_mode) {
2103 return InstanceKlass::find_method_impl(methods,
2104 name,
2105 signature,
2106 overpass_mode,
2107 static_mode,
2108 private_mode);
2109 }
2110
2111 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2112 const Symbol* name,
2113 const Symbol* signature) {
2114 return InstanceKlass::find_method_impl(methods,
2115 name,
2116 signature,
2117 OverpassLookupMode::find,
2118 StaticLookupMode::find,
2119 PrivateLookupMode::find);
2120 }
2121
2122 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2123 const Symbol* name,
2124 const Symbol* signature,
2125 OverpassLookupMode overpass_mode,
2126 StaticLookupMode static_mode,
2127 PrivateLookupMode private_mode) {
2128 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2129 return hit >= 0 ? methods->at(hit): nullptr;
2130 }
2131
2132 // true if method matches signature and conforms to skipping_X conditions.
2133 static bool method_matches(const Method* m,
2134 const Symbol* signature,
2135 bool skipping_overpass,
2136 bool skipping_static,
2137 bool skipping_private) {
2138 return ((m->signature() == signature) &&
2139 (!skipping_overpass || !m->is_overpass()) &&
2140 (!skipping_static || !m->is_static()) &&
2141 (!skipping_private || !m->is_private()));
2142 }
2143
2144 // Used directly for default_methods to find the index into the
2145 // default_vtable_indices, and indirectly by find_method
2146 // find_method_index looks in the local methods array to return the index
2147 // of the matching name/signature. If, overpass methods are being ignored,
2148 // the search continues to find a potential non-overpass match. This capability
2149 // is important during method resolution to prefer a static method, for example,
2150 // over an overpass method.
2151 // There is the possibility in any _method's array to have the same name/signature
2152 // for a static method, an overpass method and a local instance method
2153 // To correctly catch a given method, the search criteria may need
2154 // to explicitly skip the other two. For local instance methods, it
2155 // is often necessary to skip private methods
2156 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2157 const Symbol* name,
2158 const Symbol* signature,
2159 OverpassLookupMode overpass_mode,
2160 StaticLookupMode static_mode,
2161 PrivateLookupMode private_mode) {
2162 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2163 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2164 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2165 const int hit = quick_search(methods, name);
2166 if (hit != -1) {
2167 const Method* const m = methods->at(hit);
2168
2169 // Do linear search to find matching signature. First, quick check
2170 // for common case, ignoring overpasses if requested.
2171 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2172 return hit;
2173 }
2174
2175 // search downwards through overloaded methods
2176 int i;
2177 for (i = hit - 1; i >= 0; --i) {
2178 const Method* const m = methods->at(i);
2179 assert(m->is_method(), "must be method");
2180 if (m->name() != name) {
2181 break;
2182 }
2183 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2184 return i;
2185 }
2186 }
2187 // search upwards
2188 for (i = hit + 1; i < methods->length(); ++i) {
2189 const Method* const m = methods->at(i);
2190 assert(m->is_method(), "must be method");
2191 if (m->name() != name) {
2192 break;
2193 }
2194 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2195 return i;
2196 }
2197 }
2198 // not found
2199 #ifdef ASSERT
2200 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2201 linear_search(methods, name, signature);
2202 assert(-1 == index, "binary search should have found entry %d", index);
2203 #endif
2204 }
2205 return -1;
2206 }
2207
2208 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2209 return find_method_by_name(methods(), name, end);
2210 }
2211
2212 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2213 const Symbol* name,
2214 int* end_ptr) {
2215 assert(end_ptr != nullptr, "just checking");
2216 int start = quick_search(methods, name);
2217 int end = start + 1;
2218 if (start != -1) {
2219 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2220 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2221 *end_ptr = end;
2222 return start;
2223 }
2224 return -1;
2225 }
2226
2227 // uncached_lookup_method searches both the local class methods array and all
2228 // superclasses methods arrays, skipping any overpass methods in superclasses,
2229 // and possibly skipping private methods.
2230 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2231 const Symbol* signature,
2232 OverpassLookupMode overpass_mode,
2233 PrivateLookupMode private_mode) const {
2234 OverpassLookupMode overpass_local_mode = overpass_mode;
2235 const Klass* klass = this;
2236 while (klass != nullptr) {
2237 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2238 signature,
2239 overpass_local_mode,
2240 StaticLookupMode::find,
2241 private_mode);
2242 if (method != nullptr) {
2243 return method;
2244 }
2245 klass = klass->super();
2246 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2247 }
2248 return nullptr;
2249 }
2250
2251 #ifdef ASSERT
2252 // search through class hierarchy and return true if this class or
2253 // one of the superclasses was redefined
2254 bool InstanceKlass::has_redefined_this_or_super() const {
2255 const Klass* klass = this;
2256 while (klass != nullptr) {
2257 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2258 return true;
2259 }
2260 klass = klass->super();
2261 }
2262 return false;
2263 }
2264 #endif
2265
2266 // lookup a method in the default methods list then in all transitive interfaces
2267 // Do NOT return private or static methods
2268 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2269 Symbol* signature) const {
2270 Method* m = nullptr;
2271 if (default_methods() != nullptr) {
2272 m = find_method(default_methods(), name, signature);
2273 }
2274 // Look up interfaces
2275 if (m == nullptr) {
2276 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2277 }
2278 return m;
2279 }
2280
2281 // lookup a method in all the interfaces that this class implements
2282 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2283 // They should only be found in the initial InterfaceMethodRef
2284 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2285 Symbol* signature,
2286 DefaultsLookupMode defaults_mode) const {
2287 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2288 int num_ifs = all_ifs->length();
2289 InstanceKlass *ik = nullptr;
2290 for (int i = 0; i < num_ifs; i++) {
2291 ik = all_ifs->at(i);
2292 Method* m = ik->lookup_method(name, signature);
2293 if (m != nullptr && m->is_public() && !m->is_static() &&
2294 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2295 return m;
2296 }
2297 }
2298 return nullptr;
2299 }
2300
2301 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2302 :_st(st), _verbose(verbose) {
2303 ResourceMark rm;
2304 _st->print("%-18s ", "KlassAddr");
2305 _st->print("%-4s ", "Size");
2306 _st->print("%-20s ", "State");
2307 _st->print("%-7s ", "Flags");
2308 _st->print("%-5s ", "ClassName");
2309 _st->cr();
2310 }
2311
2312 void PrintClassClosure::do_klass(Klass* k) {
2313 ResourceMark rm;
2314 // klass pointer
2315 _st->print(PTR_FORMAT " ", p2i(k));
2316 // klass size
2317 _st->print("%4d ", k->size());
2318 // initialization state
2319 if (k->is_instance_klass()) {
2320 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2321 } else {
2322 _st->print("%-20s ","");
2323 }
2324 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2325 char buf[10];
2326 int i = 0;
2327 if (k->has_finalizer()) buf[i++] = 'F';
2328 if (k->is_instance_klass()) {
2329 InstanceKlass* ik = InstanceKlass::cast(k);
2330 if (ik->has_final_method()) buf[i++] = 'f';
2331 if (ik->is_rewritten()) buf[i++] = 'W';
2332 if (ik->is_contended()) buf[i++] = 'C';
2333 if (ik->has_been_redefined()) buf[i++] = 'R';
2334 if (ik->is_shared()) buf[i++] = 'S';
2335 }
2336 buf[i++] = '\0';
2337 _st->print("%-7s ", buf);
2338 // klass name
2339 _st->print("%-5s ", k->external_name());
2340 // end
2341 _st->cr();
2342 if (_verbose) {
2343 k->print_on(_st);
2344 }
2345 }
2346
2347 /* jni_id_for for jfieldIds only */
2348 JNIid* InstanceKlass::jni_id_for(int offset) {
2349 MutexLocker ml(JfieldIdCreation_lock);
2350 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2351 if (probe == nullptr) {
2352 // Allocate new static field identifier
2353 probe = new JNIid(this, offset, jni_ids());
2354 set_jni_ids(probe);
2355 }
2356 return probe;
2357 }
2358
2359 u2 InstanceKlass::enclosing_method_data(int offset) const {
2360 const Array<jushort>* const inner_class_list = inner_classes();
2361 if (inner_class_list == nullptr) {
2362 return 0;
2363 }
2364 const int length = inner_class_list->length();
2365 if (length % inner_class_next_offset == 0) {
2366 return 0;
2367 }
2368 const int index = length - enclosing_method_attribute_size;
2369 assert(offset < enclosing_method_attribute_size, "invalid offset");
2370 return inner_class_list->at(index + offset);
2371 }
2372
2373 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2374 u2 method_index) {
2375 Array<jushort>* inner_class_list = inner_classes();
2376 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2377 int length = inner_class_list->length();
2378 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2379 int index = length - enclosing_method_attribute_size;
2380 inner_class_list->at_put(
2381 index + enclosing_method_class_index_offset, class_index);
2382 inner_class_list->at_put(
2383 index + enclosing_method_method_index_offset, method_index);
2384 }
2385 }
2386
2387 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2388 if (method->is_old() && !method->is_obsolete()) {
2389 // If the method passed in is old (but not obsolete), use the current version.
2390 method = method_with_idnum((int)idnum);
2391 assert(method != nullptr, "old and but not obsolete, so should exist");
2392 }
2393 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2394 Atomic::release_store(&jmeths[idnum + 1], new_id);
2395 return new_id;
2396 }
2397
2398 // Lookup or create a jmethodID.
2399 // This code is called by the VMThread and JavaThreads so the
2400 // locking has to be done very carefully to avoid deadlocks
2401 // and/or other cache consistency problems.
2402 //
2403 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2404 Method* method = method_h();
2405 int idnum = method->method_idnum();
2406 jmethodID* jmeths = methods_jmethod_ids_acquire();
2407
2408 // We use a double-check locking idiom here because this cache is
2409 // performance sensitive. In the normal system, this cache only
2410 // transitions from null to non-null which is safe because we use
2411 // release_set_methods_jmethod_ids() to advertise the new cache.
2412 // A partially constructed cache should never be seen by a racing
2413 // thread. We also use release_store() to save a new jmethodID
2414 // in the cache so a partially constructed jmethodID should never be
2415 // seen either. Cache reads of existing jmethodIDs proceed without a
2416 // lock, but cache writes of a new jmethodID requires uniqueness and
2417 // creation of the cache itself requires no leaks so a lock is
2418 // acquired in those two cases.
2419 //
2420 // If the RedefineClasses() API has been used, then this cache grows
2421 // in the redefinition safepoint.
2422
2423 if (jmeths == nullptr) {
2424 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2425 jmeths = methods_jmethod_ids_acquire();
2426 // Still null?
2427 if (jmeths == nullptr) {
2428 size_t size = idnum_allocated_count();
2429 assert(size > (size_t)idnum, "should already have space");
2430 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2431 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2432 // cache size is stored in element[0], other elements offset by one
2433 jmeths[0] = (jmethodID)size;
2434 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2435
2436 // publish jmeths
2437 release_set_methods_jmethod_ids(jmeths);
2438 return new_id;
2439 }
2440 }
2441
2442 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2443 if (id == nullptr) {
2444 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2445 id = jmeths[idnum + 1];
2446 // Still null?
2447 if (id == nullptr) {
2448 return update_jmethod_id(jmeths, method, idnum);
2449 }
2450 }
2451 return id;
2452 }
2453
2454 void InstanceKlass::update_methods_jmethod_cache() {
2455 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2456 jmethodID* cache = _methods_jmethod_ids;
2457 if (cache != nullptr) {
2458 size_t size = idnum_allocated_count();
2459 size_t old_size = (size_t)cache[0];
2460 if (old_size < size + 1) {
2461 // Allocate a larger one and copy entries to the new one.
2462 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2463 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2464 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2465 // The cache size is stored in element[0]; the other elements are offset by one.
2466 new_cache[0] = (jmethodID)size;
2467
2468 for (int i = 1; i <= (int)old_size; i++) {
2469 new_cache[i] = cache[i];
2470 }
2471 _methods_jmethod_ids = new_cache;
2472 FREE_C_HEAP_ARRAY(jmethodID, cache);
2473 }
2474 }
2475 }
2476
2477 // Figure out how many jmethodIDs haven't been allocated, and make
2478 // sure space for them is pre-allocated. This makes getting all
2479 // method ids much, much faster with classes with more than 8
2480 // methods, and has a *substantial* effect on performance with jvmti
2481 // code that loads all jmethodIDs for all classes.
2482 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2483 int new_jmeths = 0;
2484 int length = methods()->length();
2485 for (int index = start_offset; index < length; index++) {
2486 Method* m = methods()->at(index);
2487 jmethodID id = m->find_jmethod_id_or_null();
2488 if (id == nullptr) {
2489 new_jmeths++;
2490 }
2491 }
2492 if (new_jmeths != 0) {
2493 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2494 }
2495 }
2496
2497 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2498 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2499 int idnum = method->method_idnum();
2500 jmethodID* jmeths = methods_jmethod_ids_acquire();
2501 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2502 }
2503
2504 inline DependencyContext InstanceKlass::dependencies() {
2505 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2506 return dep_context;
2507 }
2508
2509 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2510 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2511 }
2512
2513 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2514 dependencies().add_dependent_nmethod(nm);
2515 }
2516
2517 void InstanceKlass::clean_dependency_context() {
2518 dependencies().clean_unloading_dependents();
2519 }
2520
2521 #ifndef PRODUCT
2522 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2523 dependencies().print_dependent_nmethods(verbose);
2524 }
2525
2526 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2527 return dependencies().is_dependent_nmethod(nm);
2528 }
2529 #endif //PRODUCT
2530
2531 void InstanceKlass::clean_weak_instanceklass_links() {
2532 clean_implementors_list();
2533 clean_method_data();
2534 }
2535
2536 void InstanceKlass::clean_implementors_list() {
2537 assert(is_loader_alive(), "this klass should be live");
2538 if (is_interface()) {
2539 assert (ClassUnloading, "only called for ClassUnloading");
2540 for (;;) {
2541 // Use load_acquire due to competing with inserts
2542 InstanceKlass* volatile* iklass = adr_implementor();
2543 assert(iklass != nullptr, "Klass must not be null");
2544 InstanceKlass* impl = Atomic::load_acquire(iklass);
2545 if (impl != nullptr && !impl->is_loader_alive()) {
2546 // null this field, might be an unloaded instance klass or null
2547 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2548 // Successfully unlinking implementor.
2549 if (log_is_enabled(Trace, class, unload)) {
2550 ResourceMark rm;
2551 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2552 }
2553 return;
2554 }
2555 } else {
2556 return;
2557 }
2558 }
2559 }
2560 }
2561
2562 void InstanceKlass::clean_method_data() {
2563 for (int m = 0; m < methods()->length(); m++) {
2564 MethodData* mdo = methods()->at(m)->method_data();
2565 if (mdo != nullptr) {
2566 mdo->clean_method_data(/*always_clean*/false);
2567 }
2568 }
2569 }
2570
2571 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2572 Klass::metaspace_pointers_do(it);
2573
2574 if (log_is_enabled(Trace, cds)) {
2575 ResourceMark rm;
2576 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2577 }
2578
2579 it->push(&_annotations);
2580 it->push((Klass**)&_array_klasses);
2581 if (!is_rewritten()) {
2582 it->push(&_constants, MetaspaceClosure::_writable);
2583 } else {
2584 it->push(&_constants);
2585 }
2586 it->push(&_inner_classes);
2587 #if INCLUDE_JVMTI
2588 it->push(&_previous_versions);
2589 #endif
2590 #if INCLUDE_CDS
2591 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2592 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2593 // be writable. The length check on the _methods is necessary because classes which
2594 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2595 if (_methods != nullptr && _methods->length() > 0 &&
2596 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2597 // To handle jsr bytecode, new Method* maybe stored into _methods
2598 it->push(&_methods, MetaspaceClosure::_writable);
2599 } else {
2600 #endif
2601 it->push(&_methods);
2602 #if INCLUDE_CDS
2603 }
2604 #endif
2605 it->push(&_default_methods);
2606 it->push(&_local_interfaces);
2607 it->push(&_transitive_interfaces);
2608 it->push(&_method_ordering);
2609 if (!is_rewritten()) {
2610 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2611 } else {
2612 it->push(&_default_vtable_indices);
2613 }
2614
2615 it->push(&_fieldinfo_stream);
2616 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2617 it->push(&_fields_status, MetaspaceClosure::_writable);
2618
2619 if (itable_length() > 0) {
2620 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2621 int method_table_offset_in_words = ioe->offset()/wordSize;
2622 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2623
2624 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2625 / itableOffsetEntry::size();
2626
2627 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2628 if (ioe->interface_klass() != nullptr) {
2629 it->push(ioe->interface_klass_addr());
2630 itableMethodEntry* ime = ioe->first_method_entry(this);
2631 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2632 for (int index = 0; index < n; index ++) {
2633 it->push(ime[index].method_addr());
2634 }
2635 }
2636 }
2637 }
2638
2639 it->push(&_nest_host);
2640 it->push(&_nest_members);
2641 it->push(&_permitted_subclasses);
2642 it->push(&_record_components);
2643 }
2644
2645 #if INCLUDE_CDS
2646 void InstanceKlass::remove_unshareable_info() {
2647 if (is_linked()) {
2648 assert(can_be_verified_at_dumptime(), "must be");
2649 // Remember this so we can avoid walking the hierarchy at runtime.
2650 set_verified_at_dump_time();
2651 }
2652 _misc_flags.set_has_init_deps_processed(false);
2653
2654 Klass::remove_unshareable_info();
2655
2656 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2657 // Classes are attempted to link during dumping and may fail,
2658 // but these classes are still in the dictionary and class list in CLD.
2659 // If the class has failed verification, there is nothing else to remove.
2660 return;
2661 }
2662
2663 // Reset to the 'allocated' state to prevent any premature accessing to
2664 // a shared class at runtime while the class is still being loaded and
2665 // restored. A class' init_state is set to 'loaded' at runtime when it's
2666 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2667 _init_state = allocated;
2668
2669 { // Otherwise this needs to take out the Compile_lock.
2670 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2671 init_implementor();
2672 }
2673
2674 // Call remove_unshareable_info() on other objects that belong to this class, except
2675 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2676 // ArchiveBuilder::make_klasses_shareable(),
2677
2678 for (int i = 0; i < methods()->length(); i++) {
2679 Method* m = methods()->at(i);
2680 m->remove_unshareable_info();
2681 }
2682
2683 // do array classes also.
2684 if (array_klasses() != nullptr) {
2685 array_klasses()->remove_unshareable_info();
2686 }
2687
2688 // These are not allocated from metaspace. They are safe to set to null.
2689 _source_debug_extension = nullptr;
2690 _dep_context = nullptr;
2691 _osr_nmethods_head = nullptr;
2692 #if INCLUDE_JVMTI
2693 _breakpoints = nullptr;
2694 _previous_versions = nullptr;
2695 _cached_class_file = nullptr;
2696 _jvmti_cached_class_field_map = nullptr;
2697 #endif
2698
2699 _init_thread = nullptr;
2700 _methods_jmethod_ids = nullptr;
2701 _jni_ids = nullptr;
2702 _oop_map_cache = nullptr;
2703 if (CDSConfig::is_dumping_invokedynamic() && HeapShared::is_lambda_proxy_klass(this)) {
2704 // keep _nest_host
2705 } else {
2706 // clear _nest_host to ensure re-load at runtime
2707 _nest_host = nullptr;
2708 }
2709 init_shared_package_entry();
2710 _dep_context_last_cleaned = 0;
2711 DEBUG_ONLY(_shared_class_load_count = 0);
2712
2713 remove_unshareable_flags();
2714 }
2715
2716 void InstanceKlass::remove_unshareable_flags() {
2717 // clear all the flags/stats that shouldn't be in the archived version
2718 assert(!is_scratch_class(), "must be");
2719 assert(!has_been_redefined(), "must be");
2720 #if INCLUDE_JVMTI
2721 set_is_being_redefined(false);
2722 #endif
2723 set_has_resolved_methods(false);
2724 }
2725
2726 void InstanceKlass::remove_java_mirror() {
2727 Klass::remove_java_mirror();
2728
2729 // do array classes also.
2730 if (array_klasses() != nullptr) {
2731 array_klasses()->remove_java_mirror();
2732 }
2733 }
2734
2735 void InstanceKlass::init_shared_package_entry() {
2736 assert(CDSConfig::is_dumping_archive(), "must be");
2737 #if !INCLUDE_CDS_JAVA_HEAP
2738 _package_entry = nullptr;
2739 #else
2740 if (CDSConfig::is_dumping_full_module_graph()) {
2741 if (is_shared_unregistered_class()) {
2742 _package_entry = nullptr;
2743 } else {
2744 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2745 }
2746 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2747 CDSConfig::is_using_full_module_graph() &&
2748 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2749 // _package_entry is an archived package in the base archive. Leave it as is.
2750 } else {
2751 _package_entry = nullptr;
2752 }
2753 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2754 #endif
2755 }
2756
2757 void InstanceKlass::compute_has_loops_flag_for_methods() {
2758 Array<Method*>* methods = this->methods();
2759 for (int index = 0; index < methods->length(); ++index) {
2760 Method* m = methods->at(index);
2761 if (!m->is_overpass()) { // work around JDK-8305771
2762 m->compute_has_loops_flag();
2763 }
2764 }
2765 }
2766
2767 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2768 PackageEntry* pkg_entry, TRAPS) {
2769 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2770 // before the InstanceKlass is added to the SystemDictionary. Make
2771 // sure the current state is <loaded.
2772 assert(!is_loaded(), "invalid init state");
2773 assert(!shared_loading_failed(), "Must not try to load failed class again");
2774 set_package(loader_data, pkg_entry, CHECK);
2775 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2776
2777 Array<Method*>* methods = this->methods();
2778 int num_methods = methods->length();
2779 for (int index = 0; index < num_methods; ++index) {
2780 methods->at(index)->restore_unshareable_info(CHECK);
2781 }
2782 #if INCLUDE_JVMTI
2783 if (JvmtiExport::has_redefined_a_class()) {
2784 // Reinitialize vtable because RedefineClasses may have changed some
2785 // entries in this vtable for super classes so the CDS vtable might
2786 // point to old or obsolete entries. RedefineClasses doesn't fix up
2787 // vtables in the shared system dictionary, only the main one.
2788 // It also redefines the itable too so fix that too.
2789 // First fix any default methods that point to a super class that may
2790 // have been redefined.
2791 bool trace_name_printed = false;
2792 adjust_default_methods(&trace_name_printed);
2793 vtable().initialize_vtable();
2794 itable().initialize_itable();
2795 }
2796 #endif
2797
2798 // restore constant pool resolved references
2799 constants()->restore_unshareable_info(CHECK);
2800
2801 if (array_klasses() != nullptr) {
2802 // To get a consistent list of classes we need MultiArray_lock to ensure
2803 // array classes aren't observed while they are being restored.
2804 RecursiveLocker rl(MultiArray_lock, THREAD);
2805 assert(this == array_klasses()->bottom_klass(), "sanity");
2806 // Array classes have null protection domain.
2807 // --> see ArrayKlass::complete_create_array_klass()
2808 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2809 }
2810
2811 // Initialize @ValueBased class annotation
2812 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
2813 set_is_value_based();
2814 }
2815 }
2816
2817 bool InstanceKlass::can_be_verified_at_dumptime() const {
2818 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2819 return true;
2820 }
2821
2822 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2823 // This is a class that was dumped into the base archive, so we know
2824 // it was verified at dump time.
2825 return true;
2826 }
2827
2828 if (CDSConfig::is_dumping_invokedynamic()) {
2829 // FIXME: this works around JDK-8315719
2830 return true;
2831 }
2832
2833 // Check if a class or any of its supertypes has a version older than 50.
2834 // CDS will not perform verification of old classes during dump time because
2835 // without changing the old verifier, the verification constraint cannot be
2836 // retrieved during dump time.
2837 // Verification of archived old classes will be performed during run time.
2838 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2839 return false;
2840 }
2841 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2842 return false;
2843 }
2844 Array<InstanceKlass*>* interfaces = local_interfaces();
2845 int len = interfaces->length();
2846 for (int i = 0; i < len; i++) {
2847 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2848 return false;
2849 }
2850 }
2851 return true;
2852 }
2853
2854 bool InstanceKlass::methods_contain_jsr_bytecode() const {
2855 Thread* thread = Thread::current();
2856 for (int i = 0; i < _methods->length(); i++) {
2857 methodHandle m(thread, _methods->at(i));
2858 BytecodeStream bcs(m);
2859 while (!bcs.is_last_bytecode()) {
2860 Bytecodes::Code opcode = bcs.next();
2861 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
2862 return true;
2863 }
2864 }
2865 }
2866 return false;
2867 }
2868
2869 int InstanceKlass::shared_class_loader_type() const {
2870 if (is_shared_boot_class()) {
2871 return ClassLoader::BOOT_LOADER;
2872 } else if (is_shared_platform_class()) {
2873 return ClassLoader::PLATFORM_LOADER;
2874 } else if (is_shared_app_class()) {
2875 return ClassLoader::APP_LOADER;
2876 } else {
2877 return ClassLoader::OTHER;
2878 }
2879 }
2880 #endif // INCLUDE_CDS
2881
2882 #if INCLUDE_JVMTI
2883 static void clear_all_breakpoints(Method* m) {
2884 m->clear_all_breakpoints();
2885 }
2886 #endif
2887
2888 void InstanceKlass::unload_class(InstanceKlass* ik) {
2889 // Release dependencies.
2890 ik->dependencies().remove_all_dependents();
2891
2892 // notify the debugger
2893 if (JvmtiExport::should_post_class_unload()) {
2894 JvmtiExport::post_class_unload(ik);
2895 }
2896
2897 // notify ClassLoadingService of class unload
2898 ClassLoadingService::notify_class_unloaded(ik);
2899
2900 SystemDictionaryShared::handle_class_unloading(ik);
2901
2902 if (log_is_enabled(Info, class, unload)) {
2903 ResourceMark rm;
2904 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2905 }
2906
2907 Events::log_class_unloading(Thread::current(), ik);
2908
2909 #if INCLUDE_JFR
2910 assert(ik != nullptr, "invariant");
2911 EventClassUnload event;
2912 event.set_unloadedClass(ik);
2913 event.set_definingClassLoader(ik->class_loader_data());
2914 event.commit();
2915 #endif
2916 }
2917
2918 static void method_release_C_heap_structures(Method* m) {
2919 m->release_C_heap_structures();
2920 }
2921
2922 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2923 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2924 // Clean up C heap
2925 Klass::release_C_heap_structures();
2926
2927 // Deallocate and call destructors for MDO mutexes
2928 if (release_sub_metadata) {
2929 methods_do(method_release_C_heap_structures);
2930 }
2931
2932 // Deallocate oop map cache
2933 if (_oop_map_cache != nullptr) {
2934 delete _oop_map_cache;
2935 _oop_map_cache = nullptr;
2936 }
2937
2938 // Deallocate JNI identifiers for jfieldIDs
2939 JNIid::deallocate(jni_ids());
2940 set_jni_ids(nullptr);
2941
2942 jmethodID* jmeths = methods_jmethod_ids_acquire();
2943 if (jmeths != nullptr) {
2944 release_set_methods_jmethod_ids(nullptr);
2945 FreeHeap(jmeths);
2946 }
2947
2948 assert(_dep_context == nullptr,
2949 "dependencies should already be cleaned");
2950
2951 #if INCLUDE_JVMTI
2952 // Deallocate breakpoint records
2953 if (breakpoints() != 0x0) {
2954 methods_do(clear_all_breakpoints);
2955 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2956 }
2957
2958 // deallocate the cached class file
2959 if (_cached_class_file != nullptr) {
2960 os::free(_cached_class_file);
2961 _cached_class_file = nullptr;
2962 }
2963 #endif
2964
2965 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2966
2967 if (release_sub_metadata) {
2968 constants()->release_C_heap_structures();
2969 }
2970 }
2971
2972 // The constant pool is on stack if any of the methods are executing or
2973 // referenced by handles.
2974 bool InstanceKlass::on_stack() const {
2975 return _constants->on_stack();
2976 }
2977
2978 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
2979 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
2980 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
2981
2982 // minor and major version numbers of class file
2983 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
2984 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
2985 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
2986 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
2987
2988 InstanceKlass* InstanceKlass::get_klass_version(int version) {
2989 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
2990 if (ik->constants()->version() == version) {
2991 return ik;
2992 }
2993 }
2994 return nullptr;
2995 }
2996
2997 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2998 if (array == nullptr) {
2999 _source_debug_extension = nullptr;
3000 } else {
3001 // Adding one to the attribute length in order to store a null terminator
3002 // character could cause an overflow because the attribute length is
3003 // already coded with an u4 in the classfile, but in practice, it's
3004 // unlikely to happen.
3005 assert((length+1) > length, "Overflow checking");
3006 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3007 for (int i = 0; i < length; i++) {
3008 sde[i] = array[i];
3009 }
3010 sde[length] = '\0';
3011 _source_debug_extension = sde;
3012 }
3013 }
3014
3015 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3016 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3017 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3018
3019 const char* InstanceKlass::signature_name() const {
3020
3021 // Get the internal name as a c string
3022 const char* src = (const char*) (name()->as_C_string());
3023 const int src_length = (int)strlen(src);
3024
3025 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3026
3027 // Add L as type indicator
3028 int dest_index = 0;
3029 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3030
3031 // Add the actual class name
3032 for (int src_index = 0; src_index < src_length; ) {
3033 dest[dest_index++] = src[src_index++];
3034 }
3035
3036 if (is_hidden()) { // Replace the last '+' with a '.'.
3037 for (int index = (int)src_length; index > 0; index--) {
3038 if (dest[index] == '+') {
3039 dest[index] = JVM_SIGNATURE_DOT;
3040 break;
3041 }
3042 }
3043 }
3044
3045 // Add the semicolon and the null
3046 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3047 dest[dest_index] = '\0';
3048 return dest;
3049 }
3050
3051 ModuleEntry* InstanceKlass::module() const {
3052 if (is_hidden() &&
3053 in_unnamed_package() &&
3054 class_loader_data()->has_class_mirror_holder()) {
3055 // For a non-strong hidden class defined to an unnamed package,
3056 // its (class held) CLD will not have an unnamed module created for it.
3057 // Two choices to find the correct ModuleEntry:
3058 // 1. If hidden class is within a nest, use nest host's module
3059 // 2. Find the unnamed module off from the class loader
3060 // For now option #2 is used since a nest host is not set until
3061 // after the instance class is created in jvm_lookup_define_class().
3062 if (class_loader_data()->is_boot_class_loader_data()) {
3063 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3064 } else {
3065 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3066 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3067 return java_lang_Module::module_entry(module);
3068 }
3069 }
3070
3071 // Class is in a named package
3072 if (!in_unnamed_package()) {
3073 return _package_entry->module();
3074 }
3075
3076 // Class is in an unnamed package, return its loader's unnamed module
3077 return class_loader_data()->unnamed_module();
3078 }
3079
3080 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3081
3082 // ensure java/ packages only loaded by boot or platform builtin loaders
3083 // not needed for shared class since CDS does not archive prohibited classes.
3084 if (!is_shared()) {
3085 check_prohibited_package(name(), loader_data, CHECK);
3086 }
3087
3088 if (is_shared() && _package_entry != nullptr) {
3089 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3090 // we can use the saved package
3091 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3092 return;
3093 } else {
3094 _package_entry = nullptr;
3095 }
3096 }
3097
3098 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3099 // it returns, so we need to decrement it when the current function exits.
3100 TempNewSymbol from_class_name =
3101 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3102
3103 Symbol* pkg_name;
3104 if (pkg_entry != nullptr) {
3105 pkg_name = pkg_entry->name();
3106 } else {
3107 pkg_name = from_class_name;
3108 }
3109
3110 if (pkg_name != nullptr && loader_data != nullptr) {
3111
3112 // Find in class loader's package entry table.
3113 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3114
3115 // If the package name is not found in the loader's package
3116 // entry table, it is an indication that the package has not
3117 // been defined. Consider it defined within the unnamed module.
3118 if (_package_entry == nullptr) {
3119
3120 if (!ModuleEntryTable::javabase_defined()) {
3121 // Before java.base is defined during bootstrapping, define all packages in
3122 // the java.base module. If a non-java.base package is erroneously placed
3123 // in the java.base module it will be caught later when java.base
3124 // is defined by ModuleEntryTable::verify_javabase_packages check.
3125 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3126 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3127 } else {
3128 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3129 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3130 }
3131
3132 // A package should have been successfully created
3133 DEBUG_ONLY(ResourceMark rm(THREAD));
3134 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3135 name()->as_C_string(), loader_data->loader_name_and_id());
3136 }
3137
3138 if (log_is_enabled(Debug, module)) {
3139 ResourceMark rm(THREAD);
3140 ModuleEntry* m = _package_entry->module();
3141 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3142 external_name(),
3143 pkg_name->as_C_string(),
3144 loader_data->loader_name_and_id(),
3145 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3146 }
3147 } else {
3148 ResourceMark rm(THREAD);
3149 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3150 external_name(),
3151 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3152 UNNAMED_MODULE);
3153 }
3154 }
3155
3156 // Function set_classpath_index ensures that for a non-null _package_entry
3157 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3158 // It then sets the classpath_index in the package entry record.
3159 //
3160 // The classpath_index field is used to find the entry on the boot loader class
3161 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3162 // in an unnamed module. It is also used to indicate (for all packages whose
3163 // classes are loaded by the boot loader) that at least one of the package's
3164 // classes has been loaded.
3165 void InstanceKlass::set_classpath_index(s2 path_index) {
3166 if (_package_entry != nullptr) {
3167 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3168 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3169 assert(path_index != -1, "Unexpected classpath_index");
3170 _package_entry->set_classpath_index(path_index);
3171 }
3172 }
3173
3174 // different versions of is_same_class_package
3175
3176 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3177 oop classloader1 = this->class_loader();
3178 PackageEntry* classpkg1 = this->package();
3179 if (class2->is_objArray_klass()) {
3180 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3181 }
3182
3183 oop classloader2;
3184 PackageEntry* classpkg2;
3185 if (class2->is_instance_klass()) {
3186 classloader2 = class2->class_loader();
3187 classpkg2 = class2->package();
3188 } else {
3189 assert(class2->is_typeArray_klass(), "should be type array");
3190 classloader2 = nullptr;
3191 classpkg2 = nullptr;
3192 }
3193
3194 // Same package is determined by comparing class loader
3195 // and package entries. Both must be the same. This rule
3196 // applies even to classes that are defined in the unnamed
3197 // package, they still must have the same class loader.
3198 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3199 return true;
3200 }
3201
3202 return false;
3203 }
3204
3205 // return true if this class and other_class are in the same package. Classloader
3206 // and classname information is enough to determine a class's package
3207 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3208 const Symbol* other_class_name) const {
3209 if (class_loader() != other_class_loader) {
3210 return false;
3211 }
3212 if (name()->fast_compare(other_class_name) == 0) {
3213 return true;
3214 }
3215
3216 {
3217 ResourceMark rm;
3218
3219 bool bad_class_name = false;
3220 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3221 if (bad_class_name) {
3222 return false;
3223 }
3224 // Check that package_from_class_name() returns null, not "", if there is no package.
3225 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3226
3227 const Symbol* const this_package_name =
3228 this->package() != nullptr ? this->package()->name() : nullptr;
3229
3230 if (this_package_name == nullptr || other_pkg == nullptr) {
3231 // One of the two doesn't have a package. Only return true if the other
3232 // one also doesn't have a package.
3233 return this_package_name == other_pkg;
3234 }
3235
3236 // Check if package is identical
3237 return this_package_name->fast_compare(other_pkg) == 0;
3238 }
3239 }
3240
3241 static bool is_prohibited_package_slow(Symbol* class_name) {
3242 // Caller has ResourceMark
3243 int length;
3244 jchar* unicode = class_name->as_unicode(length);
3245 return (length >= 5 &&
3246 unicode[0] == 'j' &&
3247 unicode[1] == 'a' &&
3248 unicode[2] == 'v' &&
3249 unicode[3] == 'a' &&
3250 unicode[4] == '/');
3251 }
3252
3253 // Only boot and platform class loaders can define classes in "java/" packages.
3254 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3255 ClassLoaderData* loader_data,
3256 TRAPS) {
3257 if (!loader_data->is_boot_class_loader_data() &&
3258 !loader_data->is_platform_class_loader_data() &&
3259 class_name != nullptr && class_name->utf8_length() >= 5) {
3260 ResourceMark rm(THREAD);
3261 bool prohibited;
3262 const u1* base = class_name->base();
3263 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3264 prohibited = is_prohibited_package_slow(class_name);
3265 } else {
3266 char* name = class_name->as_C_string();
3267 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3268 }
3269 if (prohibited) {
3270 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3271 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3272 char* name = pkg_name->as_C_string();
3273 const char* class_loader_name = loader_data->loader_name_and_id();
3274 StringUtils::replace_no_expand(name, "/", ".");
3275 const char* msg_text1 = "Class loader (instance of): ";
3276 const char* msg_text2 = " tried to load prohibited package name: ";
3277 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3278 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3279 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3280 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3281 }
3282 }
3283 return;
3284 }
3285
3286 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3287 constantPoolHandle i_cp(THREAD, constants());
3288 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3289 int ioff = iter.inner_class_info_index();
3290 if (ioff != 0) {
3291 // Check to see if the name matches the class we're looking for
3292 // before attempting to find the class.
3293 if (i_cp->klass_name_at_matches(this, ioff)) {
3294 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3295 if (this == inner_klass) {
3296 *ooff = iter.outer_class_info_index();
3297 *noff = iter.inner_name_index();
3298 return true;
3299 }
3300 }
3301 }
3302 }
3303 return false;
3304 }
3305
3306 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3307 InstanceKlass* outer_klass = nullptr;
3308 *inner_is_member = false;
3309 int ooff = 0, noff = 0;
3310 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3311 if (has_inner_classes_attr) {
3312 constantPoolHandle i_cp(THREAD, constants());
3313 if (ooff != 0) {
3314 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3315 if (!ok->is_instance_klass()) {
3316 // If the outer class is not an instance klass then it cannot have
3317 // declared any inner classes.
3318 ResourceMark rm(THREAD);
3319 Exceptions::fthrow(
3320 THREAD_AND_LOCATION,
3321 vmSymbols::java_lang_IncompatibleClassChangeError(),
3322 "%s and %s disagree on InnerClasses attribute",
3323 ok->external_name(),
3324 external_name());
3325 return nullptr;
3326 }
3327 outer_klass = InstanceKlass::cast(ok);
3328 *inner_is_member = true;
3329 }
3330 if (nullptr == outer_klass) {
3331 // It may be a local class; try for that.
3332 int encl_method_class_idx = enclosing_method_class_index();
3333 if (encl_method_class_idx != 0) {
3334 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3335 outer_klass = InstanceKlass::cast(ok);
3336 *inner_is_member = false;
3337 }
3338 }
3339 }
3340
3341 // If no inner class attribute found for this class.
3342 if (nullptr == outer_klass) return nullptr;
3343
3344 // Throws an exception if outer klass has not declared k as an inner klass
3345 // We need evidence that each klass knows about the other, or else
3346 // the system could allow a spoof of an inner class to gain access rights.
3347 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3348 return outer_klass;
3349 }
3350
3351 jint InstanceKlass::compute_modifier_flags() const {
3352 jint access = access_flags().as_int();
3353
3354 // But check if it happens to be member class.
3355 InnerClassesIterator iter(this);
3356 for (; !iter.done(); iter.next()) {
3357 int ioff = iter.inner_class_info_index();
3358 // Inner class attribute can be zero, skip it.
3359 // Strange but true: JVM spec. allows null inner class refs.
3360 if (ioff == 0) continue;
3361
3362 // only look at classes that are already loaded
3363 // since we are looking for the flags for our self.
3364 Symbol* inner_name = constants()->klass_name_at(ioff);
3365 if (name() == inner_name) {
3366 // This is really a member class.
3367 access = iter.inner_access_flags();
3368 break;
3369 }
3370 }
3371 // Remember to strip ACC_SUPER bit
3372 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3373 }
3374
3375 jint InstanceKlass::jvmti_class_status() const {
3376 jint result = 0;
3377
3378 if (is_linked()) {
3379 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3380 }
3381
3382 if (is_initialized()) {
3383 assert(is_linked(), "Class status is not consistent");
3384 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3385 }
3386 if (is_in_error_state()) {
3387 result |= JVMTI_CLASS_STATUS_ERROR;
3388 }
3389 return result;
3390 }
3391
3392 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3393 bool implements_interface; // initialized by method_at_itable_or_null
3394 Method* m = method_at_itable_or_null(holder, index,
3395 implements_interface); // out parameter
3396 if (m != nullptr) {
3397 assert(implements_interface, "sanity");
3398 return m;
3399 } else if (implements_interface) {
3400 // Throw AbstractMethodError since corresponding itable slot is empty.
3401 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3402 } else {
3403 // If the interface isn't implemented by the receiver class,
3404 // the VM should throw IncompatibleClassChangeError.
3405 ResourceMark rm(THREAD);
3406 stringStream ss;
3407 bool same_module = (module() == holder->module());
3408 ss.print("Receiver class %s does not implement "
3409 "the interface %s defining the method to be called "
3410 "(%s%s%s)",
3411 external_name(), holder->external_name(),
3412 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3413 (same_module) ? "" : "; ",
3414 (same_module) ? "" : holder->class_in_module_of_loader());
3415 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3416 }
3417 }
3418
3419 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3420 klassItable itable(this);
3421 for (int i = 0; i < itable.size_offset_table(); i++) {
3422 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3423 if (offset_entry->interface_klass() == holder) {
3424 implements_interface = true;
3425 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3426 Method* m = ime[index].method();
3427 return m;
3428 }
3429 }
3430 implements_interface = false;
3431 return nullptr; // offset entry not found
3432 }
3433
3434 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3435 assert(is_linked(), "required");
3436 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3437 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3438
3439 int vtable_index = Method::invalid_vtable_index;
3440 Symbol* name = intf_method->name();
3441 Symbol* signature = intf_method->signature();
3442
3443 // First check in default method array
3444 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3445 int index = find_method_index(default_methods(),
3446 name, signature,
3447 Klass::OverpassLookupMode::find,
3448 Klass::StaticLookupMode::find,
3449 Klass::PrivateLookupMode::find);
3450 if (index >= 0) {
3451 vtable_index = default_vtable_indices()->at(index);
3452 }
3453 }
3454 if (vtable_index == Method::invalid_vtable_index) {
3455 // get vtable_index for miranda methods
3456 klassVtable vt = vtable();
3457 vtable_index = vt.index_of_miranda(name, signature);
3458 }
3459 return vtable_index;
3460 }
3461
3462 #if INCLUDE_JVMTI
3463 // update default_methods for redefineclasses for methods that are
3464 // not yet in the vtable due to concurrent subclass define and superinterface
3465 // redefinition
3466 // Note: those in the vtable, should have been updated via adjust_method_entries
3467 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3468 // search the default_methods for uses of either obsolete or EMCP methods
3469 if (default_methods() != nullptr) {
3470 for (int index = 0; index < default_methods()->length(); index ++) {
3471 Method* old_method = default_methods()->at(index);
3472 if (old_method == nullptr || !old_method->is_old()) {
3473 continue; // skip uninteresting entries
3474 }
3475 assert(!old_method->is_deleted(), "default methods may not be deleted");
3476 Method* new_method = old_method->get_new_method();
3477 default_methods()->at_put(index, new_method);
3478
3479 if (log_is_enabled(Info, redefine, class, update)) {
3480 ResourceMark rm;
3481 if (!(*trace_name_printed)) {
3482 log_info(redefine, class, update)
3483 ("adjust: klassname=%s default methods from name=%s",
3484 external_name(), old_method->method_holder()->external_name());
3485 *trace_name_printed = true;
3486 }
3487 log_debug(redefine, class, update, vtables)
3488 ("default method update: %s(%s) ",
3489 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3490 }
3491 }
3492 }
3493 }
3494 #endif // INCLUDE_JVMTI
3495
3496 // On-stack replacement stuff
3497 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3498 assert_lock_strong(NMethodState_lock);
3499 #ifndef PRODUCT
3500 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3501 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3502 "redundant OSR recompilation detected. memory leak in CodeCache!");
3503 #endif
3504 // only one compilation can be active
3505 assert(n->is_osr_method(), "wrong kind of nmethod");
3506 n->set_osr_link(osr_nmethods_head());
3507 set_osr_nmethods_head(n);
3508 // Raise the highest osr level if necessary
3509 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3510
3511 // Get rid of the osr methods for the same bci that have lower levels.
3512 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3513 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3514 if (inv != nullptr && inv->is_in_use()) {
3515 inv->make_not_entrant();
3516 }
3517 }
3518 }
3519
3520 // Remove osr nmethod from the list. Return true if found and removed.
3521 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3522 // This is a short non-blocking critical region, so the no safepoint check is ok.
3523 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3524 assert(n->is_osr_method(), "wrong kind of nmethod");
3525 nmethod* last = nullptr;
3526 nmethod* cur = osr_nmethods_head();
3527 int max_level = CompLevel_none; // Find the max comp level excluding n
3528 Method* m = n->method();
3529 // Search for match
3530 bool found = false;
3531 while(cur != nullptr && cur != n) {
3532 if (m == cur->method()) {
3533 // Find max level before n
3534 max_level = MAX2(max_level, cur->comp_level());
3535 }
3536 last = cur;
3537 cur = cur->osr_link();
3538 }
3539 nmethod* next = nullptr;
3540 if (cur == n) {
3541 found = true;
3542 next = cur->osr_link();
3543 if (last == nullptr) {
3544 // Remove first element
3545 set_osr_nmethods_head(next);
3546 } else {
3547 last->set_osr_link(next);
3548 }
3549 }
3550 n->set_osr_link(nullptr);
3551 cur = next;
3552 while (cur != nullptr) {
3553 // Find max level after n
3554 if (m == cur->method()) {
3555 max_level = MAX2(max_level, cur->comp_level());
3556 }
3557 cur = cur->osr_link();
3558 }
3559 m->set_highest_osr_comp_level(max_level);
3560 return found;
3561 }
3562
3563 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3564 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3565 nmethod* osr = osr_nmethods_head();
3566 int found = 0;
3567 while (osr != nullptr) {
3568 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3569 if (osr->method() == m) {
3570 deopt_scope->mark(osr);
3571 found++;
3572 }
3573 osr = osr->osr_link();
3574 }
3575 return found;
3576 }
3577
3578 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3579 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3580 nmethod* osr = osr_nmethods_head();
3581 nmethod* best = nullptr;
3582 while (osr != nullptr) {
3583 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3584 // There can be a time when a c1 osr method exists but we are waiting
3585 // for a c2 version. When c2 completes its osr nmethod we will trash
3586 // the c1 version and only be able to find the c2 version. However
3587 // while we overflow in the c1 code at back branches we don't want to
3588 // try and switch to the same code as we are already running
3589
3590 if (osr->method() == m &&
3591 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3592 if (match_level) {
3593 if (osr->comp_level() == comp_level) {
3594 // Found a match - return it.
3595 return osr;
3596 }
3597 } else {
3598 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3599 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3600 // Found the best possible - return it.
3601 return osr;
3602 }
3603 best = osr;
3604 }
3605 }
3606 }
3607 osr = osr->osr_link();
3608 }
3609
3610 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3611 if (best != nullptr && best->comp_level() >= comp_level) {
3612 return best;
3613 }
3614 return nullptr;
3615 }
3616
3617 // -----------------------------------------------------------------------------------------------------
3618 // Printing
3619
3620 #define BULLET " - "
3621
3622 static const char* state_names[] = {
3623 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3624 };
3625
3626 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3627 for (int i = 0; i < len; i++) {
3628 intptr_t e = start[i];
3629 st->print("%d : " INTPTR_FORMAT, i, e);
3630 if (MetaspaceObj::is_valid((Metadata*)e)) {
3631 st->print(" ");
3632 ((Metadata*)e)->print_value_on(st);
3633 }
3634 st->cr();
3635 }
3636 }
3637
3638 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3639 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3640 }
3641
3642 const char* InstanceKlass::init_state_name() const {
3643 return state_names[init_state()];
3644 }
3645
3646 const char* InstanceKlass::state2name(ClassState s) {
3647 return state_names[s];
3648 }
3649
3650 void InstanceKlass::print_on(outputStream* st) const {
3651 assert(is_klass(), "must be klass");
3652 Klass::print_on(st);
3653
3654 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3655 st->print(BULLET"klass size: %d", size()); st->cr();
3656 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3657 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3658 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3659 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3660 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3661 st->print(BULLET"sub: ");
3662 Klass* sub = subklass();
3663 int n;
3664 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3665 if (n < MaxSubklassPrintSize) {
3666 sub->print_value_on(st);
3667 st->print(" ");
3668 }
3669 }
3670 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3671 st->cr();
3672
3673 if (is_interface()) {
3674 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3675 if (nof_implementors() == 1) {
3676 st->print_cr(BULLET"implementor: ");
3677 st->print(" ");
3678 implementor()->print_value_on(st);
3679 st->cr();
3680 }
3681 }
3682
3683 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3684 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3685 if (Verbose || WizardMode) {
3686 Array<Method*>* method_array = methods();
3687 for (int i = 0; i < method_array->length(); i++) {
3688 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3689 }
3690 }
3691 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3692 if (default_methods() != nullptr) {
3693 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3694 if (Verbose) {
3695 Array<Method*>* method_array = default_methods();
3696 for (int i = 0; i < method_array->length(); i++) {
3697 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3698 }
3699 }
3700 }
3701 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3702 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3703 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3704
3705 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3706 if (UseSecondarySupersTable) {
3707 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3708 st->print(BULLET"bitmap: " UINTX_FORMAT_X_0, _bitmap); st->cr();
3709 }
3710 if (secondary_supers() != nullptr) {
3711 if (Verbose) {
3712 bool is_hashed = UseSecondarySupersTable && (_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3713 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3714 for (int i = 0; i < _secondary_supers->length(); i++) {
3715 ResourceMark rm; // for external_name()
3716 Klass* secondary_super = _secondary_supers->at(i);
3717 st->print(BULLET"%2d:", i);
3718 if (is_hashed) {
3719 int home_slot = compute_home_slot(secondary_super, _bitmap);
3720 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3721 st->print(" dist:%02d:", distance);
3722 }
3723 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3724 }
3725 }
3726 }
3727 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3728
3729 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3730 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3731 if (source_debug_extension() != nullptr) {
3732 st->print(BULLET"source debug extension: ");
3733 st->print("%s", source_debug_extension());
3734 st->cr();
3735 }
3736 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3737 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3738 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3739 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3740 {
3741 bool have_pv = false;
3742 // previous versions are linked together through the InstanceKlass
3743 for (InstanceKlass* pv_node = previous_versions();
3744 pv_node != nullptr;
3745 pv_node = pv_node->previous_versions()) {
3746 if (!have_pv)
3747 st->print(BULLET"previous version: ");
3748 have_pv = true;
3749 pv_node->constants()->print_value_on(st);
3750 }
3751 if (have_pv) st->cr();
3752 }
3753
3754 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3755 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3756 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3757 print_on_maybe_null(st, BULLET"record components: ", record_components());
3758 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3759 if (java_mirror() != nullptr) {
3760 st->print(BULLET"java mirror: ");
3761 java_mirror()->print_value_on(st);
3762 st->cr();
3763 } else {
3764 st->print_cr(BULLET"java mirror: null");
3765 }
3766 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3767 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3768 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3769 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3770 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3771
3772 FieldPrinter print_static_field(st);
3773 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3774 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3775 FieldPrinter print_nonstatic_field(st);
3776 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3777 ik->print_nonstatic_fields(&print_nonstatic_field);
3778
3779 st->print(BULLET"non-static oop maps: ");
3780 OopMapBlock* map = start_of_nonstatic_oop_maps();
3781 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3782 while (map < end_map) {
3783 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3784 map++;
3785 }
3786 st->cr();
3787 }
3788
3789 void InstanceKlass::print_value_on(outputStream* st) const {
3790 assert(is_klass(), "must be klass");
3791 if (Verbose || WizardMode) access_flags().print_on(st);
3792 name()->print_value_on(st);
3793 }
3794
3795 void FieldPrinter::do_field(fieldDescriptor* fd) {
3796 _st->print(BULLET);
3797 if (_obj == nullptr) {
3798 fd->print_on(_st);
3799 _st->cr();
3800 } else {
3801 fd->print_on_for(_st, _obj);
3802 _st->cr();
3803 }
3804 }
3805
3806
3807 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3808 Klass::oop_print_on(obj, st);
3809
3810 if (this == vmClasses::String_klass()) {
3811 typeArrayOop value = java_lang_String::value(obj);
3812 juint length = java_lang_String::length(obj);
3813 if (value != nullptr &&
3814 value->is_typeArray() &&
3815 length <= (juint) value->length()) {
3816 st->print(BULLET"string: ");
3817 java_lang_String::print(obj, st);
3818 st->cr();
3819 }
3820 }
3821
3822 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3823 FieldPrinter print_field(st, obj);
3824 print_nonstatic_fields(&print_field);
3825
3826 if (this == vmClasses::Class_klass()) {
3827 st->print(BULLET"signature: ");
3828 java_lang_Class::print_signature(obj, st);
3829 st->cr();
3830 Klass* real_klass = java_lang_Class::as_Klass(obj);
3831 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3832 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3833 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3834 }
3835 } else if (this == vmClasses::MethodType_klass()) {
3836 st->print(BULLET"signature: ");
3837 java_lang_invoke_MethodType::print_signature(obj, st);
3838 st->cr();
3839 }
3840 }
3841
3842 #ifndef PRODUCT
3843
3844 bool InstanceKlass::verify_itable_index(int i) {
3845 int method_count = klassItable::method_count_for_interface(this);
3846 assert(i >= 0 && i < method_count, "index out of bounds");
3847 return true;
3848 }
3849
3850 #endif //PRODUCT
3851
3852 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3853 st->print("a ");
3854 name()->print_value_on(st);
3855 obj->print_address_on(st);
3856 if (this == vmClasses::String_klass()
3857 && java_lang_String::value(obj) != nullptr) {
3858 ResourceMark rm;
3859 int len = java_lang_String::length(obj);
3860 int plen = (len < 24 ? len : 12);
3861 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3862 st->print(" = \"%s\"", str);
3863 if (len > plen)
3864 st->print("...[%d]", len);
3865 } else if (this == vmClasses::Class_klass()) {
3866 Klass* k = java_lang_Class::as_Klass(obj);
3867 st->print(" = ");
3868 if (k != nullptr) {
3869 k->print_value_on(st);
3870 } else {
3871 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3872 st->print("%s", tname ? tname : "type?");
3873 }
3874 } else if (this == vmClasses::MethodType_klass()) {
3875 st->print(" = ");
3876 java_lang_invoke_MethodType::print_signature(obj, st);
3877 } else if (java_lang_boxing_object::is_instance(obj)) {
3878 st->print(" = ");
3879 java_lang_boxing_object::print(obj, st);
3880 } else if (this == vmClasses::LambdaForm_klass()) {
3881 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3882 if (vmentry != nullptr) {
3883 st->print(" => ");
3884 vmentry->print_value_on(st);
3885 }
3886 } else if (this == vmClasses::MemberName_klass()) {
3887 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3888 if (vmtarget != nullptr) {
3889 st->print(" = ");
3890 vmtarget->print_value_on(st);
3891 } else {
3892 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3893 oop name = java_lang_invoke_MemberName::name(obj);
3894 if (clazz != nullptr) {
3895 clazz->print_value_on(st);
3896 } else {
3897 st->print("null");
3898 }
3899 st->print(".");
3900 if (name != nullptr) {
3901 name->print_value_on(st);
3902 } else {
3903 st->print("null");
3904 }
3905 }
3906 }
3907 }
3908
3909 const char* InstanceKlass::internal_name() const {
3910 return external_name();
3911 }
3912
3913 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3914 const ModuleEntry* module_entry,
3915 const ClassFileStream* cfs) const {
3916
3917 if (ClassListWriter::is_enabled()) {
3918 ClassListWriter::write(this, cfs);
3919 }
3920
3921 print_class_load_helper(loader_data, module_entry, cfs);
3922 print_class_load_cause_logging();
3923 }
3924
3925 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3926 const ModuleEntry* module_entry,
3927 const ClassFileStream* cfs) const {
3928
3929 if (!log_is_enabled(Info, class, load)) {
3930 return;
3931 }
3932
3933 ResourceMark rm;
3934 LogMessage(class, load) msg;
3935 stringStream info_stream;
3936
3937 // Name and class hierarchy info
3938 info_stream.print("%s", external_name());
3939
3940 // Source
3941 if (cfs != nullptr) {
3942 if (cfs->source() != nullptr) {
3943 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3944 if (module_name != nullptr) {
3945 // When the boot loader created the stream, it didn't know the module name
3946 // yet. Let's format it now.
3947 if (cfs->from_boot_loader_modules_image()) {
3948 info_stream.print(" source: jrt:/%s", module_name);
3949 } else {
3950 info_stream.print(" source: %s", cfs->source());
3951 }
3952 } else {
3953 info_stream.print(" source: %s", cfs->source());
3954 }
3955 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3956 Thread* current = Thread::current();
3957 Klass* caller = current->is_Java_thread() ?
3958 JavaThread::cast(current)->security_get_caller_class(1):
3959 nullptr;
3960 // caller can be null, for example, during a JVMTI VM_Init hook
3961 if (caller != nullptr) {
3962 info_stream.print(" source: instance of %s", caller->external_name());
3963 } else {
3964 // source is unknown
3965 }
3966 } else {
3967 oop class_loader = loader_data->class_loader();
3968 info_stream.print(" source: %s", class_loader->klass()->external_name());
3969 }
3970 } else {
3971 assert(this->is_shared(), "must be");
3972 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3973 info_stream.print(" source: shared objects file (top)");
3974 } else {
3975 info_stream.print(" source: shared objects file");
3976 }
3977 }
3978
3979 info_stream.print(" loader:");
3980 if (is_shared()) {
3981 info_stream.print(" %s", SystemDictionaryShared::class_loader_name_for_shared((Klass*)this));
3982 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3983 info_stream.print(" boot_loader");
3984 } else {
3985 oop class_loader = loader_data->class_loader();
3986 if (class_loader != nullptr) {
3987 info_stream.print(" %s", class_loader->klass()->external_name());
3988 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
3989 if (cl_name_and_id != nullptr) {
3990 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
3991 }
3992 } else {
3993 info_stream.print(" null");
3994 }
3995 }
3996 msg.info("%s", info_stream.as_string());
3997
3998 if (log_is_enabled(Debug, class, load)) {
3999 stringStream debug_stream;
4000
4001 // Class hierarchy info
4002 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4003 p2i(this), p2i(superklass()));
4004
4005 // Interfaces
4006 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4007 debug_stream.print(" interfaces:");
4008 int length = local_interfaces()->length();
4009 for (int i = 0; i < length; i++) {
4010 debug_stream.print(" " PTR_FORMAT,
4011 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4012 }
4013 }
4014
4015 // Class loader
4016 debug_stream.print(" loader: [");
4017 loader_data->print_value_on(&debug_stream);
4018 debug_stream.print("]");
4019
4020 // Classfile checksum
4021 if (cfs) {
4022 debug_stream.print(" bytes: %d checksum: %08x",
4023 cfs->length(),
4024 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4025 cfs->length()));
4026 }
4027
4028 msg.debug("%s", debug_stream.as_string());
4029 }
4030 }
4031
4032 void InstanceKlass::print_class_load_cause_logging() const {
4033 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4034 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4035 JavaThread* current = JavaThread::current();
4036 ResourceMark rm(current);
4037 const char* name = external_name();
4038
4039 if (LogClassLoadingCauseFor == nullptr ||
4040 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4041 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4042 return;
4043 }
4044
4045 // Log Java stack first
4046 {
4047 LogMessage(class, load, cause) msg;
4048 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4049
4050 info_stream.print_cr("Java stack when loading %s:", name);
4051 current->print_stack_on(&info_stream);
4052 }
4053
4054 // Log native stack second
4055 if (log_cause_native) {
4056 // Log to string first so that lines can be indented
4057 stringStream stack_stream;
4058 char buf[O_BUFLEN];
4059 address lastpc = nullptr;
4060 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4061 // We have printed the native stack in platform-specific code,
4062 // so nothing else to do in this case.
4063 } else {
4064 frame f = os::current_frame();
4065 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4066 -1 /* max stack_stream */, buf, O_BUFLEN);
4067 }
4068
4069 LogMessage(class, load, cause, native) msg;
4070 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4071 info_stream.print_cr("Native stack when loading %s:", name);
4072
4073 // Print each native stack line to the log
4074 int size = (int) stack_stream.size();
4075 char* stack = stack_stream.as_string();
4076 char* stack_end = stack + size;
4077 char* line_start = stack;
4078 for (char* p = stack; p < stack_end; p++) {
4079 if (*p == '\n') {
4080 *p = '\0';
4081 info_stream.print_cr("\t%s", line_start);
4082 line_start = p + 1;
4083 }
4084 }
4085 if (line_start < stack_end) {
4086 info_stream.print_cr("\t%s", line_start);
4087 }
4088 }
4089 }
4090 }
4091
4092 // Verification
4093
4094 class VerifyFieldClosure: public BasicOopIterateClosure {
4095 protected:
4096 template <class T> void do_oop_work(T* p) {
4097 oop obj = RawAccess<>::oop_load(p);
4098 if (!oopDesc::is_oop_or_null(obj)) {
4099 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4100 Universe::print_on(tty);
4101 guarantee(false, "boom");
4102 }
4103 }
4104 public:
4105 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4106 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4107 };
4108
4109 void InstanceKlass::verify_on(outputStream* st) {
4110 #ifndef PRODUCT
4111 // Avoid redundant verifies, this really should be in product.
4112 if (_verify_count == Universe::verify_count()) return;
4113 _verify_count = Universe::verify_count();
4114 #endif
4115
4116 // Verify Klass
4117 Klass::verify_on(st);
4118
4119 // Verify that klass is present in ClassLoaderData
4120 guarantee(class_loader_data()->contains_klass(this),
4121 "this class isn't found in class loader data");
4122
4123 // Verify vtables
4124 if (is_linked()) {
4125 // $$$ This used to be done only for m/s collections. Doing it
4126 // always seemed a valid generalization. (DLD -- 6/00)
4127 vtable().verify(st);
4128 }
4129
4130 // Verify first subklass
4131 if (subklass() != nullptr) {
4132 guarantee(subklass()->is_klass(), "should be klass");
4133 }
4134
4135 // Verify siblings
4136 Klass* super = this->super();
4137 Klass* sib = next_sibling();
4138 if (sib != nullptr) {
4139 if (sib == this) {
4140 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4141 }
4142
4143 guarantee(sib->is_klass(), "should be klass");
4144 guarantee(sib->super() == super, "siblings should have same superklass");
4145 }
4146
4147 // Verify local interfaces
4148 if (local_interfaces()) {
4149 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4150 for (int j = 0; j < local_interfaces->length(); j++) {
4151 InstanceKlass* e = local_interfaces->at(j);
4152 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4153 }
4154 }
4155
4156 // Verify transitive interfaces
4157 if (transitive_interfaces() != nullptr) {
4158 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4159 for (int j = 0; j < transitive_interfaces->length(); j++) {
4160 InstanceKlass* e = transitive_interfaces->at(j);
4161 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4162 }
4163 }
4164
4165 // Verify methods
4166 if (methods() != nullptr) {
4167 Array<Method*>* methods = this->methods();
4168 for (int j = 0; j < methods->length(); j++) {
4169 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4170 }
4171 for (int j = 0; j < methods->length() - 1; j++) {
4172 Method* m1 = methods->at(j);
4173 Method* m2 = methods->at(j + 1);
4174 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4175 }
4176 }
4177
4178 // Verify method ordering
4179 if (method_ordering() != nullptr) {
4180 Array<int>* method_ordering = this->method_ordering();
4181 int length = method_ordering->length();
4182 if (JvmtiExport::can_maintain_original_method_order() ||
4183 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4184 guarantee(length == methods()->length(), "invalid method ordering length");
4185 jlong sum = 0;
4186 for (int j = 0; j < length; j++) {
4187 int original_index = method_ordering->at(j);
4188 guarantee(original_index >= 0, "invalid method ordering index");
4189 guarantee(original_index < length, "invalid method ordering index");
4190 sum += original_index;
4191 }
4192 // Verify sum of indices 0,1,...,length-1
4193 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4194 } else {
4195 guarantee(length == 0, "invalid method ordering length");
4196 }
4197 }
4198
4199 // Verify default methods
4200 if (default_methods() != nullptr) {
4201 Array<Method*>* methods = this->default_methods();
4202 for (int j = 0; j < methods->length(); j++) {
4203 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4204 }
4205 for (int j = 0; j < methods->length() - 1; j++) {
4206 Method* m1 = methods->at(j);
4207 Method* m2 = methods->at(j + 1);
4208 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4209 }
4210 }
4211
4212 // Verify JNI static field identifiers
4213 if (jni_ids() != nullptr) {
4214 jni_ids()->verify(this);
4215 }
4216
4217 // Verify other fields
4218 if (constants() != nullptr) {
4219 guarantee(constants()->is_constantPool(), "should be constant pool");
4220 }
4221 }
4222
4223 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4224 Klass::oop_verify_on(obj, st);
4225 VerifyFieldClosure blk;
4226 obj->oop_iterate(&blk);
4227 }
4228
4229
4230 // JNIid class for jfieldIDs only
4231 // Note to reviewers:
4232 // These JNI functions are just moved over to column 1 and not changed
4233 // in the compressed oops workspace.
4234 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4235 _holder = holder;
4236 _offset = offset;
4237 _next = next;
4238 debug_only(_is_static_field_id = false;)
4239 }
4240
4241
4242 JNIid* JNIid::find(int offset) {
4243 JNIid* current = this;
4244 while (current != nullptr) {
4245 if (current->offset() == offset) return current;
4246 current = current->next();
4247 }
4248 return nullptr;
4249 }
4250
4251 void JNIid::deallocate(JNIid* current) {
4252 while (current != nullptr) {
4253 JNIid* next = current->next();
4254 delete current;
4255 current = next;
4256 }
4257 }
4258
4259
4260 void JNIid::verify(Klass* holder) {
4261 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4262 int end_field_offset;
4263 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4264
4265 JNIid* current = this;
4266 while (current != nullptr) {
4267 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4268 #ifdef ASSERT
4269 int o = current->offset();
4270 if (current->is_static_field_id()) {
4271 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4272 }
4273 #endif
4274 current = current->next();
4275 }
4276 }
4277
4278 void InstanceKlass::set_init_state(ClassState state) {
4279 #ifdef ASSERT
4280 bool good_state = is_shared() ? (_init_state <= state)
4281 : (_init_state < state);
4282 assert(good_state || state == allocated, "illegal state transition");
4283 #endif
4284 assert(_init_thread == nullptr, "should be cleared before state change");
4285 _init_state = state;
4286 }
4287
4288 #if INCLUDE_JVMTI
4289
4290 // RedefineClasses() support for previous versions
4291
4292 // Globally, there is at least one previous version of a class to walk
4293 // during class unloading, which is saved because old methods in the class
4294 // are still running. Otherwise the previous version list is cleaned up.
4295 bool InstanceKlass::_should_clean_previous_versions = false;
4296
4297 // Returns true if there are previous versions of a class for class
4298 // unloading only. Also resets the flag to false. purge_previous_version
4299 // will set the flag to true if there are any left, i.e., if there's any
4300 // work to do for next time. This is to avoid the expensive code cache
4301 // walk in CLDG::clean_deallocate_lists().
4302 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4303 bool ret = _should_clean_previous_versions;
4304 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4305 ret ? "true" : "false");
4306 _should_clean_previous_versions = false;
4307 return ret;
4308 }
4309
4310 // This nulls out jmethodIDs for all methods in 'klass'
4311 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4312 // during class unloading.
4313 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4314 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4315 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4316 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4317 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4318 Array<Method*>* method_refs = klass->methods();
4319 for (int k = 0; k < method_refs->length(); k++) {
4320 Method* method = method_refs->at(k);
4321 if (method != nullptr && method->is_obsolete()) {
4322 method->clear_jmethod_id();
4323 }
4324 }
4325 }
4326
4327 // Purge previous versions before adding new previous versions of the class and
4328 // during class unloading.
4329 void InstanceKlass::purge_previous_version_list() {
4330 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4331 assert(has_been_redefined(), "Should only be called for main class");
4332
4333 // Quick exit.
4334 if (previous_versions() == nullptr) {
4335 return;
4336 }
4337
4338 // This klass has previous versions so see what we can cleanup
4339 // while it is safe to do so.
4340
4341 int deleted_count = 0; // leave debugging breadcrumbs
4342 int live_count = 0;
4343 ClassLoaderData* loader_data = class_loader_data();
4344 assert(loader_data != nullptr, "should never be null");
4345
4346 ResourceMark rm;
4347 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4348
4349 // previous versions are linked together through the InstanceKlass
4350 InstanceKlass* pv_node = previous_versions();
4351 InstanceKlass* last = this;
4352 int version = 0;
4353
4354 // check the previous versions list
4355 for (; pv_node != nullptr; ) {
4356
4357 ConstantPool* pvcp = pv_node->constants();
4358 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4359
4360 if (!pvcp->on_stack()) {
4361 // If the constant pool isn't on stack, none of the methods
4362 // are executing. Unlink this previous_version.
4363 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4364 // so will be deallocated during the next phase of class unloading.
4365 log_trace(redefine, class, iklass, purge)
4366 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4367 // Unlink from previous version list.
4368 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4369 InstanceKlass* next = pv_node->previous_versions();
4370 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4371 pv_node->link_previous_versions(nullptr); // point next to null
4372 last->link_previous_versions(next);
4373 // Delete this node directly. Nothing is referring to it and we don't
4374 // want it to increase the counter for metadata to delete in CLDG.
4375 MetadataFactory::free_metadata(loader_data, pv_node);
4376 pv_node = next;
4377 deleted_count++;
4378 version++;
4379 continue;
4380 } else {
4381 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4382 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4383 live_count++;
4384 if (pvcp->is_shared()) {
4385 // Shared previous versions can never be removed so no cleaning is needed.
4386 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4387 } else {
4388 // Previous version alive, set that clean is needed for next time.
4389 _should_clean_previous_versions = true;
4390 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4391 }
4392 }
4393
4394 // next previous version
4395 last = pv_node;
4396 pv_node = pv_node->previous_versions();
4397 version++;
4398 }
4399 log_trace(redefine, class, iklass, purge)
4400 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4401 }
4402
4403 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4404 int emcp_method_count) {
4405 int obsolete_method_count = old_methods->length() - emcp_method_count;
4406
4407 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4408 _previous_versions != nullptr) {
4409 // We have a mix of obsolete and EMCP methods so we have to
4410 // clear out any matching EMCP method entries the hard way.
4411 int local_count = 0;
4412 for (int i = 0; i < old_methods->length(); i++) {
4413 Method* old_method = old_methods->at(i);
4414 if (old_method->is_obsolete()) {
4415 // only obsolete methods are interesting
4416 Symbol* m_name = old_method->name();
4417 Symbol* m_signature = old_method->signature();
4418
4419 // previous versions are linked together through the InstanceKlass
4420 int j = 0;
4421 for (InstanceKlass* prev_version = _previous_versions;
4422 prev_version != nullptr;
4423 prev_version = prev_version->previous_versions(), j++) {
4424
4425 Array<Method*>* method_refs = prev_version->methods();
4426 for (int k = 0; k < method_refs->length(); k++) {
4427 Method* method = method_refs->at(k);
4428
4429 if (!method->is_obsolete() &&
4430 method->name() == m_name &&
4431 method->signature() == m_signature) {
4432 // The current RedefineClasses() call has made all EMCP
4433 // versions of this method obsolete so mark it as obsolete
4434 log_trace(redefine, class, iklass, add)
4435 ("%s(%s): flush obsolete method @%d in version @%d",
4436 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4437
4438 method->set_is_obsolete();
4439 break;
4440 }
4441 }
4442
4443 // The previous loop may not find a matching EMCP method, but
4444 // that doesn't mean that we can optimize and not go any
4445 // further back in the PreviousVersion generations. The EMCP
4446 // method for this generation could have already been made obsolete,
4447 // but there still may be an older EMCP method that has not
4448 // been made obsolete.
4449 }
4450
4451 if (++local_count >= obsolete_method_count) {
4452 // no more obsolete methods so bail out now
4453 break;
4454 }
4455 }
4456 }
4457 }
4458 }
4459
4460 // Save the scratch_class as the previous version if any of the methods are running.
4461 // The previous_versions are used to set breakpoints in EMCP methods and they are
4462 // also used to clean MethodData links to redefined methods that are no longer running.
4463 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4464 int emcp_method_count) {
4465 assert(Thread::current()->is_VM_thread(),
4466 "only VMThread can add previous versions");
4467
4468 ResourceMark rm;
4469 log_trace(redefine, class, iklass, add)
4470 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4471
4472 // Clean out old previous versions for this class
4473 purge_previous_version_list();
4474
4475 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4476 // a previous redefinition may be made obsolete by this redefinition.
4477 Array<Method*>* old_methods = scratch_class->methods();
4478 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4479
4480 // If the constant pool for this previous version of the class
4481 // is not marked as being on the stack, then none of the methods
4482 // in this previous version of the class are on the stack so
4483 // we don't need to add this as a previous version.
4484 ConstantPool* cp_ref = scratch_class->constants();
4485 if (!cp_ref->on_stack()) {
4486 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4487 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4488 return;
4489 }
4490
4491 // Add previous version if any methods are still running or if this is
4492 // a shared class which should never be removed.
4493 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4494 scratch_class->link_previous_versions(previous_versions());
4495 link_previous_versions(scratch_class);
4496 if (cp_ref->is_shared()) {
4497 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4498 } else {
4499 // We only set clean_previous_versions flag for processing during class
4500 // unloading for non-shared classes.
4501 _should_clean_previous_versions = true;
4502 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4503 }
4504 } // end add_previous_version()
4505
4506 #endif // INCLUDE_JVMTI
4507
4508 Method* InstanceKlass::method_with_idnum(int idnum) {
4509 Method* m = nullptr;
4510 if (idnum < methods()->length()) {
4511 m = methods()->at(idnum);
4512 }
4513 if (m == nullptr || m->method_idnum() != idnum) {
4514 for (int index = 0; index < methods()->length(); ++index) {
4515 m = methods()->at(index);
4516 if (m->method_idnum() == idnum) {
4517 return m;
4518 }
4519 }
4520 // None found, return null for the caller to handle.
4521 return nullptr;
4522 }
4523 return m;
4524 }
4525
4526
4527 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4528 if (idnum >= methods()->length()) {
4529 return nullptr;
4530 }
4531 Method* m = methods()->at(idnum);
4532 if (m != nullptr && m->orig_method_idnum() == idnum) {
4533 return m;
4534 }
4535 // Obsolete method idnum does not match the original idnum
4536 for (int index = 0; index < methods()->length(); ++index) {
4537 m = methods()->at(index);
4538 if (m->orig_method_idnum() == idnum) {
4539 return m;
4540 }
4541 }
4542 // None found, return null for the caller to handle.
4543 return nullptr;
4544 }
4545
4546
4547 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4548 InstanceKlass* holder = get_klass_version(version);
4549 if (holder == nullptr) {
4550 return nullptr; // The version of klass is gone, no method is found
4551 }
4552 Method* method = holder->method_with_orig_idnum(idnum);
4553 return method;
4554 }
4555
4556 #if INCLUDE_JVMTI
4557 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4558 return _cached_class_file;
4559 }
4560
4561 jint InstanceKlass::get_cached_class_file_len() {
4562 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4563 }
4564
4565 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4566 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4567 }
4568 #endif
4569
4570 // Make a step iterating over the class hierarchy under the root class.
4571 // Skips subclasses if requested.
4572 void ClassHierarchyIterator::next() {
4573 assert(_current != nullptr, "required");
4574 if (_visit_subclasses && _current->subklass() != nullptr) {
4575 _current = _current->subklass();
4576 return; // visit next subclass
4577 }
4578 _visit_subclasses = true; // reset
4579 while (_current->next_sibling() == nullptr && _current != _root) {
4580 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4581 }
4582 if (_current == _root) {
4583 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4584 _current = nullptr;
4585 return;
4586 }
4587 _current = _current->next_sibling();
4588 return; // visit next sibling subclass
4589 }