1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotClassInitializer.hpp"
26 #include "cds/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 "klass.inline.hpp"
56 #include "logging/logMessage.hpp"
57 #include "logging/logStream.hpp"
58 #include "memory/allocation.inline.hpp"
59 #include "memory/iterator.inline.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceClosure.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "memory/universe.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/constantPool.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/runtimeUpcalls.hpp"
93 #include "runtime/synchronizer.hpp"
94 #include "runtime/threads.hpp"
95 #include "services/classLoadingService.hpp"
96 #include "services/finalizerService.hpp"
97 #include "services/threadService.hpp"
98 #include "utilities/dtrace.hpp"
99 #include "utilities/events.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/nativeStackPrinter.hpp"
102 #include "utilities/stringUtils.hpp"
103 #ifdef COMPILER1
104 #include "c1/c1_Compiler.hpp"
105 #endif
106 #if INCLUDE_JFR
107 #include "jfr/jfrEvents.hpp"
108 #endif
109
110 #ifdef DTRACE_ENABLED
111
112
113 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
114 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
115 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
116 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
117 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
118 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
119 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
120 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
121 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
122 { \
123 char* data = nullptr; \
124 int len = 0; \
125 Symbol* clss_name = name(); \
126 if (clss_name != nullptr) { \
127 data = (char*)clss_name->bytes(); \
128 len = clss_name->utf8_length(); \
129 } \
130 HOTSPOT_CLASS_INITIALIZATION_##type( \
131 data, len, (void*)class_loader(), thread_type); \
132 }
133
134 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
135 { \
136 char* data = nullptr; \
137 int len = 0; \
138 Symbol* clss_name = name(); \
139 if (clss_name != nullptr) { \
140 data = (char*)clss_name->bytes(); \
141 len = clss_name->utf8_length(); \
142 } \
143 HOTSPOT_CLASS_INITIALIZATION_##type( \
144 data, len, (void*)class_loader(), thread_type, wait); \
145 }
146
147 #else // ndef DTRACE_ENABLED
148
149 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
150 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
151
152 #endif // ndef DTRACE_ENABLED
153
154 bool InstanceKlass::_finalization_enabled = true;
155
156 static inline bool is_class_loader(const Symbol* class_name,
157 const ClassFileParser& parser) {
158 assert(class_name != nullptr, "invariant");
159
160 if (class_name == vmSymbols::java_lang_ClassLoader()) {
161 return true;
162 }
163
164 if (vmClasses::ClassLoader_klass_loaded()) {
165 const Klass* const super_klass = parser.super_klass();
166 if (super_klass != nullptr) {
167 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
168 return true;
169 }
170 }
171 }
172 return false;
173 }
174
175 static inline bool is_stack_chunk_class(const Symbol* class_name,
176 const ClassLoaderData* loader_data) {
177 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
178 loader_data->is_the_null_class_loader_data());
179 }
180
181 // private: called to verify that k is a static member of this nest.
182 // We know that k is an instance class in the same package and hence the
183 // same classloader.
184 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
185 assert(!is_hidden(), "unexpected hidden class");
186 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
187 if (log_is_enabled(Trace, class, nestmates)) {
188 ResourceMark rm(current);
189 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
190 k->external_name(), this->external_name());
191 }
192 return false;
193 }
194
195 if (log_is_enabled(Trace, class, nestmates)) {
196 ResourceMark rm(current);
197 log_trace(class, nestmates)("Checking nest membership of %s in %s",
198 k->external_name(), this->external_name());
199 }
200
201 // Check for the named class in _nest_members.
202 // We don't resolve, or load, any classes.
203 for (int i = 0; i < _nest_members->length(); i++) {
204 int cp_index = _nest_members->at(i);
205 Symbol* name = _constants->klass_name_at(cp_index);
206 if (name == k->name()) {
207 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
208 return true;
209 }
210 }
211 log_trace(class, nestmates)("- class is NOT a nest member!");
212 return false;
213 }
214
215 // Called to verify that k is a permitted subclass of this class.
216 // The incoming stringStream is used to format the messages for error logging and for the caller
217 // to use for exception throwing.
218 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
219 Thread* current = Thread::current();
220 assert(k != nullptr, "sanity check");
221 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
222 "unexpected empty _permitted_subclasses array");
223
224 if (log_is_enabled(Trace, class, sealed)) {
225 ResourceMark rm(current);
226 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
227 k->external_name(), this->external_name());
228 }
229
230 // Check that the class and its super are in the same module.
231 if (k->module() != this->module()) {
232 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
233 "and sealed class %s is in module '%s' with loader %s",
234 k->external_name(),
235 k->module()->name_as_C_string(),
236 k->module()->loader_data()->loader_name_and_id(),
237 this->external_name(),
238 this->module()->name_as_C_string(),
239 this->module()->loader_data()->loader_name_and_id());
240 log_trace(class, sealed)(" - %s", ss.as_string());
241 return false;
242 }
243
244 if (!k->is_public() && !is_same_class_package(k)) {
245 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
246 "and sealed class %s is in package '%s' with classloader %s",
247 k->external_name(),
248 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
249 k->module()->loader_data()->loader_name_and_id(),
250 this->external_name(),
251 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
252 this->module()->loader_data()->loader_name_and_id());
253 log_trace(class, sealed)(" - %s", ss.as_string());
254 return false;
255 }
256
257 for (int i = 0; i < _permitted_subclasses->length(); i++) {
258 int cp_index = _permitted_subclasses->at(i);
259 Symbol* name = _constants->klass_name_at(cp_index);
260 if (name == k->name()) {
261 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
262 return true;
263 }
264 }
265
266 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
267 k->external_name(), this->external_name());
268 log_trace(class, sealed)(" - %s", ss.as_string());
269 return false;
270 }
271
272 // Return nest-host class, resolving, validating and saving it if needed.
273 // In cases where this is called from a thread that cannot do classloading
274 // (such as a native JIT thread) then we simply return null, which in turn
275 // causes the access check to return false. Such code will retry the access
276 // from a more suitable environment later. Otherwise the _nest_host is always
277 // set once this method returns.
278 // Any errors from nest-host resolution must be preserved so they can be queried
279 // from higher-level access checking code, and reported as part of access checking
280 // exceptions.
281 // VirtualMachineErrors are propagated with a null return.
282 // Under any conditions where the _nest_host can be set to non-null the resulting
283 // value of it and, if applicable, the nest host resolution/validation error,
284 // are idempotent.
285 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
286 InstanceKlass* nest_host_k = _nest_host;
287 if (nest_host_k != nullptr) {
288 return nest_host_k;
289 }
290
291 ResourceMark rm(THREAD);
292
293 // need to resolve and save our nest-host class.
294 if (_nest_host_index != 0) { // we have a real nest_host
295 // Before trying to resolve check if we're in a suitable context
296 bool can_resolve = THREAD->can_call_java();
297 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
298 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
299 this->external_name());
300 return nullptr; // sentinel to say "try again from a different context"
301 }
302
303 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
304 this->external_name(),
305 _constants->klass_name_at(_nest_host_index)->as_C_string());
306
307 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
308 if (HAS_PENDING_EXCEPTION) {
309 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
310 return nullptr; // propagate VMEs
311 }
312 stringStream ss;
313 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
314 ss.print("Nest host resolution of %s with host %s failed: ",
315 this->external_name(), target_host_class);
316 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
317 const char* msg = ss.as_string(true /* on C-heap */);
318 constantPoolHandle cph(THREAD, constants());
319 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
320 CLEAR_PENDING_EXCEPTION;
321
322 log_trace(class, nestmates)("%s", msg);
323 } else {
324 // A valid nest-host is an instance class in the current package that lists this
325 // class as a nest member. If any of these conditions are not met the class is
326 // its own nest-host.
327 const char* error = nullptr;
328
329 // JVMS 5.4.4 indicates package check comes first
330 if (is_same_class_package(k)) {
331 // Now check actual membership. We can't be a member if our "host" is
332 // not an instance class.
333 if (k->is_instance_klass()) {
334 nest_host_k = InstanceKlass::cast(k);
335 bool is_member = nest_host_k->has_nest_member(THREAD, this);
336 if (is_member) {
337 _nest_host = nest_host_k; // save resolved nest-host value
338
339 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
340 this->external_name(), k->external_name());
341 return nest_host_k;
342 } else {
343 error = "current type is not listed as a nest member";
344 }
345 } else {
346 error = "host is not an instance class";
347 }
348 } else {
349 error = "types are in different packages";
350 }
351
352 // something went wrong, so record what and log it
353 {
354 stringStream ss;
355 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
356 this->external_name(),
357 this->class_loader_data()->loader_name_and_id(),
358 k->external_name(),
359 k->class_loader_data()->loader_name_and_id(),
360 error);
361 const char* msg = ss.as_string(true /* on C-heap */);
362 constantPoolHandle cph(THREAD, constants());
363 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
364 log_trace(class, nestmates)("%s", msg);
365 }
366 }
367 } else {
368 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
369 this->external_name());
370 }
371
372 // Either not in an explicit nest, or else an error occurred, so
373 // the nest-host is set to `this`. Any thread that sees this assignment
374 // will also see any setting of nest_host_error(), if applicable.
375 return (_nest_host = this);
376 }
377
378 // Dynamic nest member support: set this class's nest host to the given class.
379 // This occurs as part of the class definition, as soon as the instanceKlass
380 // has been created and doesn't require further resolution. The code:
381 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
382 // results in:
383 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
384 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
385 // We also know the "host" is a valid nest-host in the same package so we can
386 // assert some of those facts.
387 void InstanceKlass::set_nest_host(InstanceKlass* host) {
388 assert(is_hidden(), "must be a hidden class");
389 assert(host != nullptr, "null nest host specified");
390 assert(_nest_host == nullptr, "current class has resolved nest-host");
391 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
392 nest_host_error());
393 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
394 (host->_nest_host == host), "proposed host is not a valid nest-host");
395 // Can't assert this as package is not set yet:
396 // assert(is_same_class_package(host), "proposed host is in wrong package");
397
398 if (log_is_enabled(Trace, class, nestmates)) {
399 ResourceMark rm;
400 const char* msg = "";
401 // a hidden class does not expect a statically defined nest-host
402 if (_nest_host_index > 0) {
403 msg = "(the NestHost attribute in the current class is ignored)";
404 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
405 msg = "(the NestMembers attribute in the current class is ignored)";
406 }
407 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
408 this->external_name(),
409 host->external_name(),
410 msg);
411 }
412 // set dynamic nest host
413 _nest_host = host;
414 // Record dependency to keep nest host from being unloaded before this class.
415 ClassLoaderData* this_key = class_loader_data();
416 assert(this_key != nullptr, "sanity");
417 this_key->record_dependency(host);
418 }
419
420 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
421 // or we are k's nest_host - all of which is covered by comparing the two
422 // resolved_nest_hosts.
423 // Any exceptions (i.e. VMEs) are propagated.
424 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
425
426 assert(this != k, "this should be handled by higher-level code");
427
428 // Per JVMS 5.4.4 we first resolve and validate the current class, then
429 // the target class k.
430
431 InstanceKlass* cur_host = nest_host(CHECK_false);
432 if (cur_host == nullptr) {
433 return false;
434 }
435
436 Klass* k_nest_host = k->nest_host(CHECK_false);
437 if (k_nest_host == nullptr) {
438 return false;
439 }
440
441 bool access = (cur_host == k_nest_host);
442
443 ResourceMark rm(THREAD);
444 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
445 this->external_name(),
446 access ? "" : "NOT ",
447 k->external_name());
448 return access;
449 }
450
451 const char* InstanceKlass::nest_host_error() {
452 if (_nest_host_index == 0) {
453 return nullptr;
454 } else {
455 constantPoolHandle cph(Thread::current(), constants());
456 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
457 }
458 }
459
460 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
461 bool use_class_space, TRAPS) throw() {
462 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
463 }
464
465 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
466 const int size = InstanceKlass::size(parser.vtable_size(),
467 parser.itable_size(),
468 nonstatic_oop_map_size(parser.total_oop_map_count()),
469 parser.is_interface());
470
471 const Symbol* const class_name = parser.class_name();
472 assert(class_name != nullptr, "invariant");
473 ClassLoaderData* loader_data = parser.loader_data();
474 assert(loader_data != nullptr, "invariant");
475
476 InstanceKlass* ik;
477 const bool use_class_space = parser.klass_needs_narrow_id();
478
479 // Allocation
480 if (parser.is_instance_ref_klass()) {
481 // java.lang.ref.Reference
482 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
483 } else if (class_name == vmSymbols::java_lang_Class()) {
484 // mirror - java.lang.Class
485 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
486 } else if (is_stack_chunk_class(class_name, loader_data)) {
487 // stack chunk
488 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
489 } else if (is_class_loader(class_name, parser)) {
490 // class loader - java.lang.ClassLoader
491 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
492 } else {
493 // normal
494 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
495 }
496
497 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
498 assert(CompressedKlassPointers::is_encodable(ik),
499 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
500 }
501
502 // Check for pending exception before adding to the loader data and incrementing
503 // class count. Can get OOM here.
504 if (HAS_PENDING_EXCEPTION) {
505 return nullptr;
506 }
507
508 return ik;
509 }
510
511
512 // copy method ordering from resource area to Metaspace
513 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
514 if (m != nullptr) {
515 // allocate a new array and copy contents (memcpy?)
516 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
517 for (int i = 0; i < m->length(); i++) {
518 _method_ordering->at_put(i, m->at(i));
519 }
520 } else {
521 _method_ordering = Universe::the_empty_int_array();
522 }
523 }
524
525 // create a new array of vtable_indices for default methods
526 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
527 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
528 assert(default_vtable_indices() == nullptr, "only create once");
529 set_default_vtable_indices(vtable_indices);
530 return vtable_indices;
531 }
532
533
534 InstanceKlass::InstanceKlass() {
535 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
536 }
537
538 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
539 Klass(kind),
540 _nest_members(nullptr),
541 _nest_host(nullptr),
542 _permitted_subclasses(nullptr),
543 _record_components(nullptr),
544 _static_field_size(parser.static_field_size()),
545 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
546 _itable_len(parser.itable_size()),
547 _nest_host_index(0),
548 _init_state(allocated),
549 _reference_type(reference_type),
550 _init_thread(nullptr)
551 {
552 set_vtable_length(parser.vtable_size());
553 set_access_flags(parser.access_flags());
554 if (parser.is_hidden()) set_is_hidden();
555 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
556 false));
557
558 assert(nullptr == _methods, "underlying memory not zeroed?");
559 assert(is_instance_klass(), "is layout incorrect?");
560 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
561 }
562
563 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
564 Array<Method*>* methods) {
565 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
566 !methods->is_shared()) {
567 for (int i = 0; i < methods->length(); i++) {
568 Method* method = methods->at(i);
569 if (method == nullptr) continue; // maybe null if error processing
570 // Only want to delete methods that are not executing for RedefineClasses.
571 // The previous version will point to them so they're not totally dangling
572 assert (!method->on_stack(), "shouldn't be called with methods on stack");
573 MetadataFactory::free_metadata(loader_data, method);
574 }
575 MetadataFactory::free_array<Method*>(loader_data, methods);
576 }
577 }
578
579 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
580 const Klass* super_klass,
581 Array<InstanceKlass*>* local_interfaces,
582 Array<InstanceKlass*>* transitive_interfaces) {
583 // Only deallocate transitive interfaces if not empty, same as super class
584 // or same as local interfaces. See code in parseClassFile.
585 Array<InstanceKlass*>* ti = transitive_interfaces;
586 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
587 // check that the interfaces don't come from super class
588 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
589 InstanceKlass::cast(super_klass)->transitive_interfaces();
590 if (ti != sti && ti != nullptr && !ti->is_shared()) {
591 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
592 }
593 }
594
595 // local interfaces can be empty
596 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
597 local_interfaces != nullptr && !local_interfaces->is_shared()) {
598 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
599 }
600 }
601
602 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
603 Array<RecordComponent*>* record_components) {
604 if (record_components != nullptr && !record_components->is_shared()) {
605 for (int i = 0; i < record_components->length(); i++) {
606 RecordComponent* record_component = record_components->at(i);
607 MetadataFactory::free_metadata(loader_data, record_component);
608 }
609 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
610 }
611 }
612
613 // This function deallocates the metadata and C heap pointers that the
614 // InstanceKlass points to.
615 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
616 // Orphan the mirror first, CMS thinks it's still live.
617 if (java_mirror() != nullptr) {
618 java_lang_Class::set_klass(java_mirror(), nullptr);
619 }
620
621 // Also remove mirror from handles
622 loader_data->remove_handle(_java_mirror);
623
624 // Need to take this class off the class loader data list.
625 loader_data->remove_class(this);
626
627 // The array_klass for this class is created later, after error handling.
628 // For class redefinition, we keep the original class so this scratch class
629 // doesn't have an array class. Either way, assert that there is nothing
630 // to deallocate.
631 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
632
633 // Release C heap allocated data that this points to, which includes
634 // reference counting symbol names.
635 // Can't release the constant pool or MethodData C heap data here because the constant
636 // pool can be deallocated separately from the InstanceKlass for default methods and
637 // redefine classes. MethodData can also be released separately.
638 release_C_heap_structures(/* release_sub_metadata */ false);
639
640 deallocate_methods(loader_data, methods());
641 set_methods(nullptr);
642
643 deallocate_record_components(loader_data, record_components());
644 set_record_components(nullptr);
645
646 if (method_ordering() != nullptr &&
647 method_ordering() != Universe::the_empty_int_array() &&
648 !method_ordering()->is_shared()) {
649 MetadataFactory::free_array<int>(loader_data, method_ordering());
650 }
651 set_method_ordering(nullptr);
652
653 // default methods can be empty
654 if (default_methods() != nullptr &&
655 default_methods() != Universe::the_empty_method_array() &&
656 !default_methods()->is_shared()) {
657 MetadataFactory::free_array<Method*>(loader_data, default_methods());
658 }
659 // Do NOT deallocate the default methods, they are owned by superinterfaces.
660 set_default_methods(nullptr);
661
662 // default methods vtable indices can be empty
663 if (default_vtable_indices() != nullptr &&
664 !default_vtable_indices()->is_shared()) {
665 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
666 }
667 set_default_vtable_indices(nullptr);
668
669
670 // This array is in Klass, but remove it with the InstanceKlass since
671 // this place would be the only caller and it can share memory with transitive
672 // interfaces.
673 if (secondary_supers() != nullptr &&
674 secondary_supers() != Universe::the_empty_klass_array() &&
675 // see comments in compute_secondary_supers about the following cast
676 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
677 !secondary_supers()->is_shared()) {
678 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
679 }
680 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
681
682 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
683 set_transitive_interfaces(nullptr);
684 set_local_interfaces(nullptr);
685
686 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
687 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
688 }
689 set_fieldinfo_stream(nullptr);
690
691 if (fields_status() != nullptr && !fields_status()->is_shared()) {
692 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
693 }
694 set_fields_status(nullptr);
695
696 // If a method from a redefined class is using this constant pool, don't
697 // delete it, yet. The new class's previous version will point to this.
698 if (constants() != nullptr) {
699 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
700 if (!constants()->is_shared()) {
701 MetadataFactory::free_metadata(loader_data, constants());
702 }
703 // Delete any cached resolution errors for the constant pool
704 SystemDictionary::delete_resolution_error(constants());
705
706 set_constants(nullptr);
707 }
708
709 if (inner_classes() != nullptr &&
710 inner_classes() != Universe::the_empty_short_array() &&
711 !inner_classes()->is_shared()) {
712 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
713 }
714 set_inner_classes(nullptr);
715
716 if (nest_members() != nullptr &&
717 nest_members() != Universe::the_empty_short_array() &&
718 !nest_members()->is_shared()) {
719 MetadataFactory::free_array<jushort>(loader_data, nest_members());
720 }
721 set_nest_members(nullptr);
722
723 if (permitted_subclasses() != nullptr &&
724 permitted_subclasses() != Universe::the_empty_short_array() &&
725 !permitted_subclasses()->is_shared()) {
726 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
727 }
728 set_permitted_subclasses(nullptr);
729
730 // We should deallocate the Annotations instance if it's not in shared spaces.
731 if (annotations() != nullptr && !annotations()->is_shared()) {
732 MetadataFactory::free_metadata(loader_data, annotations());
733 }
734 set_annotations(nullptr);
735
736 SystemDictionaryShared::handle_class_unloading(this);
737
738 #if INCLUDE_CDS_JAVA_HEAP
739 if (CDSConfig::is_dumping_heap()) {
740 HeapShared::remove_scratch_objects(this);
741 }
742 #endif
743 }
744
745 bool InstanceKlass::is_record() const {
746 return _record_components != nullptr &&
747 is_final() &&
748 java_super() == vmClasses::Record_klass();
749 }
750
751 bool InstanceKlass::is_sealed() const {
752 return _permitted_subclasses != nullptr &&
753 _permitted_subclasses != Universe::the_empty_short_array();
754 }
755
756 // JLS 8.9: An enum class is either implicitly final and derives
757 // from java.lang.Enum, or else is implicitly sealed to its
758 // anonymous subclasses. This query detects both kinds.
759 // It does not validate the finality or
760 // sealing conditions: it merely checks for a super of Enum.
761 // This is sufficient for recognizing well-formed enums.
762 bool InstanceKlass::is_enum_subclass() const {
763 InstanceKlass* s = java_super();
764 return (s == vmClasses::Enum_klass() ||
765 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
766 }
767
768 bool InstanceKlass::should_be_initialized() const {
769 return !is_initialized();
770 }
771
772 klassItable InstanceKlass::itable() const {
773 return klassItable(const_cast<InstanceKlass*>(this));
774 }
775
776 // JVMTI spec thinks there are signers and protection domain in the
777 // instanceKlass. These accessors pretend these fields are there.
778 // The hprof specification also thinks these fields are in InstanceKlass.
779 oop InstanceKlass::protection_domain() const {
780 // return the protection_domain from the mirror
781 return java_lang_Class::protection_domain(java_mirror());
782 }
783
784 objArrayOop InstanceKlass::signers() const {
785 // return the signers from the mirror
786 return java_lang_Class::signers(java_mirror());
787 }
788
789 oop InstanceKlass::init_lock() const {
790 // return the init lock from the mirror
791 oop lock = java_lang_Class::init_lock(java_mirror());
792 // Prevent reordering with any access of initialization state
793 OrderAccess::loadload();
794 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
795 "only fully initialized state can have a null lock");
796 return lock;
797 }
798
799 // Set the initialization lock to null so the object can be GC'ed. Any racing
800 // threads to get this lock will see a null lock and will not lock.
801 // That's okay because they all check for initialized state after getting
802 // the lock and return.
803 void InstanceKlass::fence_and_clear_init_lock() {
804 // make sure previous stores are all done, notably the init_state.
805 OrderAccess::storestore();
806 java_lang_Class::clear_init_lock(java_mirror());
807 assert(!is_not_initialized(), "class must be initialized now");
808 }
809
810
811 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
812 // process. The step comments refers to the procedure described in that section.
813 // Note: implementation moved to static method to expose the this pointer.
814 void InstanceKlass::initialize(TRAPS) {
815 if (this->should_be_initialized()) {
816 initialize_impl(CHECK);
817 // Note: at this point the class may be initialized
818 // OR it may be in the state of being initialized
819 // in case of recursive initialization!
820 } else {
821 assert(is_initialized(), "sanity check");
822 }
823 }
824
825 #ifdef ASSERT
826 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
827 assert(has_aot_initialized_mirror(), "must be");
828
829 InstanceKlass* s = java_super();
830 if (s != nullptr) {
831 DEBUG_ONLY(ResourceMark rm);
832 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
833 s->external_name(), external_name());
834 s->assert_no_clinit_will_run_for_aot_initialized_class();
835 }
836
837 Array<InstanceKlass*>* interfaces = local_interfaces();
838 int len = interfaces->length();
839 for (int i = 0; i < len; i++) {
840 InstanceKlass* intf = interfaces->at(i);
841 if (!intf->is_initialized()) {
842 ResourceMark rm;
843 // Note: an interface needs to be marked as is_initialized() only if
844 // - it has a <clinit>
845 // - it has declared a default method.
846 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
847 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
848 intf->external_name(), external_name());
849 }
850 }
851 }
852 #endif
853
854 #if INCLUDE_CDS
855 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
856 assert(has_aot_initialized_mirror(), "must be");
857 assert(CDSConfig::is_loading_heap(), "must be");
858 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
859 assert_no_clinit_will_run_for_aot_initialized_class();
860
861 if (is_initialized()) {
862 return;
863 }
864
865 if (is_runtime_setup_required()) {
866 // Need to take the slow path, which will call the runtimeSetup() function instead
867 // of <clinit>
868 initialize(CHECK);
869 return;
870 }
871 if (log_is_enabled(Info, aot, init)) {
872 ResourceMark rm;
873 log_info(aot, init)("%s (aot-inited)", external_name());
874 }
875
876 link_class(CHECK);
877
878 #ifdef ASSERT
879 {
880 Handle h_init_lock(THREAD, init_lock());
881 ObjectLocker ol(h_init_lock, THREAD);
882 assert(!is_initialized(), "sanity");
883 assert(!is_being_initialized(), "sanity");
884 assert(!is_in_error_state(), "sanity");
885 }
886 #endif
887
888 set_init_thread(THREAD);
889 set_initialization_state_and_notify(fully_initialized, CHECK);
890 }
891 #endif
892
893 bool InstanceKlass::verify_code(TRAPS) {
894 // 1) Verify the bytecodes
895 return Verifier::verify(this, should_verify_class(), THREAD);
896 }
897
898 void InstanceKlass::link_class(TRAPS) {
899 assert(is_loaded(), "must be loaded");
900 if (!is_linked()) {
901 link_class_impl(CHECK);
902 }
903 }
904
905 // Called to verify that a class can link during initialization, without
906 // throwing a VerifyError.
907 bool InstanceKlass::link_class_or_fail(TRAPS) {
908 assert(is_loaded(), "must be loaded");
909 if (!is_linked()) {
910 link_class_impl(CHECK_false);
911 }
912 return is_linked();
913 }
914
915 bool InstanceKlass::link_class_impl(TRAPS) {
916 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
917 // This is for CDS static dump only -- we use the in_error_state to indicate that
918 // the class has failed verification. Throwing the NoClassDefFoundError here is just
919 // a convenient way to stop repeat attempts to verify the same (bad) class.
920 //
921 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
922 // if we are executing Java code. This is not a problem for CDS dumping phase since
923 // it doesn't execute any Java code.
924 ResourceMark rm(THREAD);
925 // Names are all known to be < 64k so we know this formatted message is not excessively large.
926 Exceptions::fthrow(THREAD_AND_LOCATION,
927 vmSymbols::java_lang_NoClassDefFoundError(),
928 "Class %s, or one of its supertypes, failed class initialization",
929 external_name());
930 return false;
931 }
932 // return if already verified
933 if (is_linked()) {
934 return true;
935 }
936
937 // Timing
938 // timer handles recursion
939 JavaThread* jt = THREAD;
940
941 // link super class before linking this class
942 Klass* super_klass = super();
943 if (super_klass != nullptr) {
944 if (super_klass->is_interface()) { // check if super class is an interface
945 ResourceMark rm(THREAD);
946 // Names are all known to be < 64k so we know this formatted message is not excessively large.
947 Exceptions::fthrow(
948 THREAD_AND_LOCATION,
949 vmSymbols::java_lang_IncompatibleClassChangeError(),
950 "class %s has interface %s as super class",
951 external_name(),
952 super_klass->external_name()
953 );
954 return false;
955 }
956
957 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
958 ik_super->link_class_impl(CHECK_false);
959 }
960
961 // link all interfaces implemented by this class before linking this class
962 Array<InstanceKlass*>* interfaces = local_interfaces();
963 int num_interfaces = interfaces->length();
964 for (int index = 0; index < num_interfaces; index++) {
965 InstanceKlass* interk = interfaces->at(index);
966 interk->link_class_impl(CHECK_false);
967 }
968
969 // in case the class is linked in the process of linking its superclasses
970 if (is_linked()) {
971 return true;
972 }
973
974 // trace only the link time for this klass that includes
975 // the verification time
976 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
977 ClassLoader::perf_class_link_selftime(),
978 ClassLoader::perf_classes_linked(),
979 jt->get_thread_stat()->perf_recursion_counts_addr(),
980 jt->get_thread_stat()->perf_timers_addr(),
981 PerfClassTraceTime::CLASS_LINK);
982
983 // verification & rewriting
984 {
985 HandleMark hm(THREAD);
986 Handle h_init_lock(THREAD, init_lock());
987 ObjectLocker ol(h_init_lock, jt);
988 // rewritten will have been set if loader constraint error found
989 // on an earlier link attempt
990 // don't verify or rewrite if already rewritten
991 //
992
993 if (!is_linked()) {
994 if (!is_rewritten()) {
995 if (is_shared()) {
996 assert(!verified_at_dump_time(), "must be");
997 }
998 {
999 bool verify_ok = verify_code(THREAD);
1000 if (!verify_ok) {
1001 return false;
1002 }
1003 }
1004
1005 // Just in case a side-effect of verify linked this class already
1006 // (which can sometimes happen since the verifier loads classes
1007 // using custom class loaders, which are free to initialize things)
1008 if (is_linked()) {
1009 return true;
1010 }
1011
1012 // also sets rewritten
1013 rewrite_class(CHECK_false);
1014 } else if (is_shared()) {
1015 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1016 }
1017
1018 // relocate jsrs and link methods after they are all rewritten
1019 link_methods(CHECK_false);
1020
1021 // Initialize the vtable and interface table after
1022 // methods have been rewritten since rewrite may
1023 // fabricate new Method*s.
1024 // also does loader constraint checking
1025 //
1026 // initialize_vtable and initialize_itable need to be rerun
1027 // for a shared class if
1028 // 1) the class is loaded by custom class loader or
1029 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1030 // 3) the class was not verified during dump time
1031 bool need_init_table = true;
1032 if (is_shared() && verified_at_dump_time() &&
1033 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1034 need_init_table = false;
1035 }
1036 if (need_init_table) {
1037 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1038 itable().initialize_itable_and_check_constraints(CHECK_false);
1039 }
1040 #ifdef ASSERT
1041 vtable().verify(tty, true);
1042 // In case itable verification is ever added.
1043 // itable().verify(tty, true);
1044 #endif
1045 if (Universe::is_fully_initialized()) {
1046 DeoptimizationScope deopt_scope;
1047 {
1048 // Now mark all code that assumes the class is not linked.
1049 // Set state under the Compile_lock also.
1050 MutexLocker ml(THREAD, Compile_lock);
1051
1052 set_init_state(linked);
1053 CodeCache::mark_dependents_on(&deopt_scope, this);
1054 }
1055 // Perform the deopt handshake outside Compile_lock.
1056 deopt_scope.deoptimize_marked();
1057 } else {
1058 set_init_state(linked);
1059 }
1060 if (JvmtiExport::should_post_class_prepare()) {
1061 JvmtiExport::post_class_prepare(THREAD, this);
1062 }
1063 }
1064 }
1065 return true;
1066 }
1067
1068 // Rewrite the byte codes of all of the methods of a class.
1069 // The rewriter must be called exactly once. Rewriting must happen after
1070 // verification but before the first method of the class is executed.
1071 void InstanceKlass::rewrite_class(TRAPS) {
1072 assert(is_loaded(), "must be loaded");
1073 if (is_rewritten()) {
1074 assert(is_shared(), "rewriting an unshared class?");
1075 return;
1076 }
1077 Rewriter::rewrite(this, CHECK);
1078 set_rewritten();
1079 }
1080
1081 // Now relocate and link method entry points after class is rewritten.
1082 // This is outside is_rewritten flag. In case of an exception, it can be
1083 // executed more than once.
1084 void InstanceKlass::link_methods(TRAPS) {
1085 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1086
1087 int len = methods()->length();
1088 for (int i = len-1; i >= 0; i--) {
1089 methodHandle m(THREAD, methods()->at(i));
1090 RuntimeUpcalls::install_upcalls(m);
1091
1092 // Set up method entry points for compiler and interpreter .
1093 m->link_method(m, CHECK);
1094 }
1095 }
1096
1097 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1098 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1099 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1100 for (int i = 0; i < local_interfaces()->length(); ++i) {
1101 InstanceKlass* ik = local_interfaces()->at(i);
1102
1103 // Initialization is depth first search ie. we start with top of the inheritance tree
1104 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1105 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1106 if (ik->has_nonstatic_concrete_methods()) {
1107 ik->initialize_super_interfaces(CHECK);
1108 }
1109
1110 // Only initialize() interfaces that "declare" concrete methods.
1111 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1112 ik->initialize(CHECK);
1113 }
1114 }
1115 }
1116
1117 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1118 static InitializationErrorTable* _initialization_error_table;
1119
1120 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1121 // Create the same exception with a message indicating the thread name,
1122 // and the StackTraceElements.
1123 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1124 ResourceMark rm(current);
1125 if (init_error.is_null()) {
1126 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1127
1128 // We failed to create the new exception, most likely due to either out-of-memory or
1129 // a stackoverflow error. If the original exception was either of those then we save
1130 // the shared, pre-allocated, stackless, instance of that exception.
1131 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1132 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1133 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1134 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1135 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1136 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1137 } else {
1138 return;
1139 }
1140 }
1141
1142 MutexLocker ml(current, ClassInitError_lock);
1143 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1144 bool created;
1145 if (_initialization_error_table == nullptr) {
1146 _initialization_error_table = new (mtClass) InitializationErrorTable();
1147 }
1148 _initialization_error_table->put_if_absent(this, elem, &created);
1149 assert(created, "Initialization is single threaded");
1150 log_trace(class, init)("Initialization error added for class %s", external_name());
1151 }
1152
1153 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1154 MutexLocker ml(current, ClassInitError_lock);
1155 if (_initialization_error_table == nullptr) {
1156 return nullptr;
1157 }
1158 OopHandle* h = _initialization_error_table->get(this);
1159 return (h != nullptr) ? h->resolve() : nullptr;
1160 }
1161
1162 // Need to remove entries for unloaded classes.
1163 void InstanceKlass::clean_initialization_error_table() {
1164 struct InitErrorTableCleaner {
1165 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1166 if (!ik->is_loader_alive()) {
1167 h.release(Universe::vm_global());
1168 return true;
1169 } else {
1170 return false;
1171 }
1172 }
1173 };
1174
1175 assert_locked_or_safepoint(ClassInitError_lock);
1176 InitErrorTableCleaner cleaner;
1177 if (_initialization_error_table != nullptr) {
1178 _initialization_error_table->unlink(&cleaner);
1179 }
1180 }
1181
1182 void InstanceKlass::initialize_impl(TRAPS) {
1183 HandleMark hm(THREAD);
1184
1185 // Make sure klass is linked (verified) before initialization
1186 // A class could already be verified, since it has been reflected upon.
1187 link_class(CHECK);
1188
1189 DTRACE_CLASSINIT_PROBE(required, -1);
1190
1191 bool wait = false;
1192
1193 JavaThread* jt = THREAD;
1194
1195 if (ForceProfiling) {
1196 // Preallocate MDOs.
1197 for (int i = 0; i < methods()->length(); i++) {
1198 assert(!HAS_PENDING_EXCEPTION, "");
1199 methodHandle m(THREAD, methods()->at(i));
1200 Method::build_profiling_method_data(m, THREAD);
1201 if (HAS_PENDING_EXCEPTION) {
1202 ResourceMark rm;
1203 log_warning(cds)("MDO preallocation failed for %s", external_name());
1204 CLEAR_PENDING_EXCEPTION;
1205 break;
1206 }
1207 }
1208 }
1209
1210 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1211
1212 // refer to the JVM book page 47 for description of steps
1213 // Step 1
1214 {
1215 Handle h_init_lock(THREAD, init_lock());
1216 ObjectLocker ol(h_init_lock, jt);
1217
1218 // Step 2
1219 // If we were to use wait() instead of waitInterruptibly() then
1220 // we might end up throwing IE from link/symbol resolution sites
1221 // that aren't expected to throw. This would wreak havoc. See 6320309.
1222 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1223 if (debug_logging_enabled) {
1224 ResourceMark rm(jt);
1225 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1226 jt->name(), external_name(), init_thread_name());
1227 }
1228 wait = true;
1229 jt->set_class_to_be_initialized(this);
1230 ol.wait_uninterruptibly(jt);
1231 jt->set_class_to_be_initialized(nullptr);
1232 }
1233
1234 // Step 3
1235 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1236 if (debug_logging_enabled) {
1237 ResourceMark rm(jt);
1238 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1239 jt->name(), external_name());
1240 }
1241 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1242 return;
1243 }
1244
1245 // Step 4
1246 if (is_initialized()) {
1247 if (debug_logging_enabled) {
1248 ResourceMark rm(jt);
1249 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1250 jt->name(), external_name());
1251 }
1252 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1253 return;
1254 }
1255
1256 // Step 5
1257 if (is_in_error_state()) {
1258 if (debug_logging_enabled) {
1259 ResourceMark rm(jt);
1260 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1261 jt->name(), external_name());
1262 }
1263
1264 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1265 ResourceMark rm(THREAD);
1266 Handle cause(THREAD, get_initialization_error(THREAD));
1267
1268 stringStream ss;
1269 ss.print("Could not initialize class %s", external_name());
1270 if (cause.is_null()) {
1271 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1272 } else {
1273 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1274 ss.as_string(), cause);
1275 }
1276 } else {
1277
1278 // Step 6
1279 set_init_state(being_initialized);
1280 set_init_thread(jt);
1281 if (debug_logging_enabled) {
1282 ResourceMark rm(jt);
1283 log_debug(class, init)("Thread \"%s\" is initializing %s",
1284 jt->name(), external_name());
1285 }
1286 }
1287 }
1288
1289 // Step 7
1290 // Next, if C is a class rather than an interface, initialize it's super class and super
1291 // interfaces.
1292 if (!is_interface()) {
1293 Klass* super_klass = super();
1294 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1295 super_klass->initialize(THREAD);
1296 }
1297 // If C implements any interface that declares a non-static, concrete method,
1298 // the initialization of C triggers initialization of its super interfaces.
1299 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1300 // having a superinterface that declares, non-static, concrete methods
1301 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1302 initialize_super_interfaces(THREAD);
1303 }
1304
1305 // If any exceptions, complete abruptly, throwing the same exception as above.
1306 if (HAS_PENDING_EXCEPTION) {
1307 Handle e(THREAD, PENDING_EXCEPTION);
1308 CLEAR_PENDING_EXCEPTION;
1309 {
1310 EXCEPTION_MARK;
1311 add_initialization_error(THREAD, e);
1312 // Locks object, set state, and notify all waiting threads
1313 set_initialization_state_and_notify(initialization_error, THREAD);
1314 CLEAR_PENDING_EXCEPTION;
1315 }
1316 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1317 THROW_OOP(e());
1318 }
1319 }
1320
1321
1322 // Step 8
1323 {
1324 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1325 if (class_initializer() != nullptr) {
1326 // Timer includes any side effects of class initialization (resolution,
1327 // etc), but not recursive entry into call_class_initializer().
1328 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1329 ClassLoader::perf_class_init_selftime(),
1330 ClassLoader::perf_classes_inited(),
1331 jt->get_thread_stat()->perf_recursion_counts_addr(),
1332 jt->get_thread_stat()->perf_timers_addr(),
1333 PerfClassTraceTime::CLASS_CLINIT);
1334 call_class_initializer(THREAD);
1335 } else {
1336 // The elapsed time is so small it's not worth counting.
1337 if (UsePerfData) {
1338 ClassLoader::perf_classes_inited()->inc();
1339 }
1340 call_class_initializer(THREAD);
1341 }
1342 }
1343
1344 // Step 9
1345 if (!HAS_PENDING_EXCEPTION) {
1346 set_initialization_state_and_notify(fully_initialized, CHECK);
1347 DEBUG_ONLY(vtable().verify(tty, true);)
1348 CompilationPolicy::replay_training_at_init(this, THREAD);
1349 }
1350 else {
1351 // Step 10 and 11
1352 Handle e(THREAD, PENDING_EXCEPTION);
1353 CLEAR_PENDING_EXCEPTION;
1354 // JVMTI has already reported the pending exception
1355 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1356 JvmtiExport::clear_detected_exception(jt);
1357 {
1358 EXCEPTION_MARK;
1359 add_initialization_error(THREAD, e);
1360 set_initialization_state_and_notify(initialization_error, THREAD);
1361 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1362 // JVMTI has already reported the pending exception
1363 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1364 JvmtiExport::clear_detected_exception(jt);
1365 }
1366 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1367 if (e->is_a(vmClasses::Error_klass())) {
1368 THROW_OOP(e());
1369 } else {
1370 JavaCallArguments args(e);
1371 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1372 vmSymbols::throwable_void_signature(),
1373 &args);
1374 }
1375 }
1376 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1377 }
1378
1379 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1380 Handle h_init_lock(THREAD, init_lock());
1381 if (h_init_lock() != nullptr) {
1382 ObjectLocker ol(h_init_lock, THREAD);
1383 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1384 set_init_state(state);
1385 fence_and_clear_init_lock();
1386 ol.notify_all(CHECK);
1387 } else {
1388 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1389 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1390 set_init_state(state);
1391 }
1392 }
1393
1394 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1395 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1396 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1397 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1398
1399 DeoptimizationScope deopt_scope;
1400 {
1401 MutexLocker ml(current, Compile_lock);
1402
1403 set_init_state(InstanceKlass::loaded);
1404 // make sure init_state store is already done.
1405 // The compiler reads the hierarchy outside of the Compile_lock.
1406 // Access ordering is used to add to hierarchy.
1407
1408 // Link into hierarchy.
1409 append_to_sibling_list(); // add to superklass/sibling list
1410 process_interfaces(); // handle all "implements" declarations
1411
1412 // Now mark all code that depended on old class hierarchy.
1413 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1414 if (Universe::is_fully_initialized()) {
1415 CodeCache::mark_dependents_on(&deopt_scope, this);
1416 }
1417 }
1418 // Perform the deopt handshake outside Compile_lock.
1419 deopt_scope.deoptimize_marked();
1420 }
1421
1422
1423 InstanceKlass* InstanceKlass::implementor() const {
1424 InstanceKlass* volatile* ik = adr_implementor();
1425 if (ik == nullptr) {
1426 return nullptr;
1427 } else {
1428 // This load races with inserts, and therefore needs acquire.
1429 InstanceKlass* ikls = Atomic::load_acquire(ik);
1430 if (ikls != nullptr && !ikls->is_loader_alive()) {
1431 return nullptr; // don't return unloaded class
1432 } else {
1433 return ikls;
1434 }
1435 }
1436 }
1437
1438
1439 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1440 assert_locked_or_safepoint(Compile_lock);
1441 assert(is_interface(), "not interface");
1442 InstanceKlass* volatile* addr = adr_implementor();
1443 assert(addr != nullptr, "null addr");
1444 if (addr != nullptr) {
1445 Atomic::release_store(addr, ik);
1446 }
1447 }
1448
1449 int InstanceKlass::nof_implementors() const {
1450 InstanceKlass* ik = implementor();
1451 if (ik == nullptr) {
1452 return 0;
1453 } else if (ik != this) {
1454 return 1;
1455 } else {
1456 return 2;
1457 }
1458 }
1459
1460 // The embedded _implementor field can only record one implementor.
1461 // When there are more than one implementors, the _implementor field
1462 // is set to the interface Klass* itself. Following are the possible
1463 // values for the _implementor field:
1464 // null - no implementor
1465 // implementor Klass* - one implementor
1466 // self - more than one implementor
1467 //
1468 // The _implementor field only exists for interfaces.
1469 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1470 if (Universe::is_fully_initialized()) {
1471 assert_lock_strong(Compile_lock);
1472 }
1473 assert(is_interface(), "not interface");
1474 // Filter out my subinterfaces.
1475 // (Note: Interfaces are never on the subklass list.)
1476 if (ik->is_interface()) return;
1477
1478 // Filter out subclasses whose supers already implement me.
1479 // (Note: CHA must walk subclasses of direct implementors
1480 // in order to locate indirect implementors.)
1481 InstanceKlass* super_ik = ik->java_super();
1482 if (super_ik != nullptr && super_ik->implements_interface(this))
1483 // We only need to check one immediate superclass, since the
1484 // implements_interface query looks at transitive_interfaces.
1485 // Any supers of the super have the same (or fewer) transitive_interfaces.
1486 return;
1487
1488 InstanceKlass* iklass = implementor();
1489 if (iklass == nullptr) {
1490 set_implementor(ik);
1491 } else if (iklass != this && iklass != ik) {
1492 // There is already an implementor. Use itself as an indicator of
1493 // more than one implementors.
1494 set_implementor(this);
1495 }
1496
1497 // The implementor also implements the transitive_interfaces
1498 for (int index = 0; index < local_interfaces()->length(); index++) {
1499 local_interfaces()->at(index)->add_implementor(ik);
1500 }
1501 }
1502
1503 void InstanceKlass::init_implementor() {
1504 if (is_interface()) {
1505 set_implementor(nullptr);
1506 }
1507 }
1508
1509
1510 void InstanceKlass::process_interfaces() {
1511 // link this class into the implementors list of every interface it implements
1512 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1513 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1514 InstanceKlass* interf = local_interfaces()->at(i);
1515 assert(interf->is_interface(), "expected interface");
1516 interf->add_implementor(this);
1517 }
1518 }
1519
1520 bool InstanceKlass::can_be_primary_super_slow() const {
1521 if (is_interface())
1522 return false;
1523 else
1524 return Klass::can_be_primary_super_slow();
1525 }
1526
1527 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1528 Array<InstanceKlass*>* transitive_interfaces) {
1529 // The secondaries are the implemented interfaces.
1530 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1531 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1532 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1533 int num_secondaries = num_extra_slots + interfaces->length();
1534 if (num_secondaries == 0) {
1535 // Must share this for correct bootstrapping!
1536 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1537 return nullptr;
1538 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1539 // We will reuse the transitive interfaces list if we're certain
1540 // it's in hash order.
1541 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1542 set_secondary_supers(interfaces, bitmap);
1543 return nullptr;
1544 }
1545 // Copy transitive interfaces to a temporary growable array to be constructed
1546 // into the secondary super list with extra slots.
1547 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1548 for (int i = 0; i < interfaces->length(); i++) {
1549 secondaries->push(interfaces->at(i));
1550 }
1551 return secondaries;
1552 }
1553
1554 bool InstanceKlass::implements_interface(Klass* k) const {
1555 if (this == k) return true;
1556 assert(k->is_interface(), "should be an interface class");
1557 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1558 if (transitive_interfaces()->at(i) == k) {
1559 return true;
1560 }
1561 }
1562 return false;
1563 }
1564
1565 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1566 // Verify direct super interface
1567 if (this == k) return true;
1568 assert(k->is_interface(), "should be an interface class");
1569 for (int i = 0; i < local_interfaces()->length(); i++) {
1570 if (local_interfaces()->at(i) == k) {
1571 return true;
1572 }
1573 }
1574 return false;
1575 }
1576
1577 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1578 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1579 size_t size = objArrayOopDesc::object_size(length);
1580 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1581 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1582 /* do_zero */ true, CHECK_NULL);
1583 return o;
1584 }
1585
1586 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1587 if (TraceFinalizerRegistration) {
1588 tty->print("Registered ");
1589 i->print_value_on(tty);
1590 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1591 }
1592 instanceHandle h_i(THREAD, i);
1593 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1594 JavaValue result(T_VOID);
1595 JavaCallArguments args(h_i);
1596 methodHandle mh(THREAD, Universe::finalizer_register_method());
1597 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1598 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1599 return h_i();
1600 }
1601
1602 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1603 assert(!is_abstract() && !is_interface(), "Should not create this object");
1604 size_t size = size_helper(); // Query before forming handle.
1605 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1606 }
1607
1608 instanceOop InstanceKlass::allocate_instance(oop java_class,
1609 const char* who,
1610 TRAPS) {
1611 Klass* k = java_lang_Class::as_Klass(java_class);
1612 if (k == nullptr) {
1613 ResourceMark rm(THREAD);
1614 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1615 }
1616 InstanceKlass* ik = cast(k);
1617 ik->check_valid_for_instantiation(false, CHECK_NULL);
1618 ik->initialize(CHECK_NULL);
1619 return ik->allocate_instance(THREAD);
1620 }
1621
1622 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1623 return instanceHandle(THREAD, allocate_instance(THREAD));
1624 }
1625
1626 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1627 if (is_interface() || is_abstract()) {
1628 ResourceMark rm(THREAD);
1629 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1630 : vmSymbols::java_lang_InstantiationException(), external_name());
1631 }
1632 if (this == vmClasses::Class_klass()) {
1633 ResourceMark rm(THREAD);
1634 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1635 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1636 }
1637 }
1638
1639 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1640 // Need load-acquire for lock-free read
1641 if (array_klasses_acquire() == nullptr) {
1642
1643 // Recursively lock array allocation
1644 RecursiveLocker rl(MultiArray_lock, THREAD);
1645
1646 // Check if another thread created the array klass while we were waiting for the lock.
1647 if (array_klasses() == nullptr) {
1648 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1649 // use 'release' to pair with lock-free load
1650 release_set_array_klasses(k);
1651 }
1652 }
1653
1654 // array_klasses() will always be set at this point
1655 ObjArrayKlass* ak = array_klasses();
1656 assert(ak != nullptr, "should be set");
1657 return ak->array_klass(n, THREAD);
1658 }
1659
1660 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1661 // Need load-acquire for lock-free read
1662 ObjArrayKlass* oak = array_klasses_acquire();
1663 if (oak == nullptr) {
1664 return nullptr;
1665 } else {
1666 return oak->array_klass_or_null(n);
1667 }
1668 }
1669
1670 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1671 return array_klass(1, THREAD);
1672 }
1673
1674 ArrayKlass* InstanceKlass::array_klass_or_null() {
1675 return array_klass_or_null(1);
1676 }
1677
1678 static int call_class_initializer_counter = 0; // for debugging
1679
1680 Method* InstanceKlass::class_initializer() const {
1681 Method* clinit = find_method(
1682 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1683 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1684 return clinit;
1685 }
1686 return nullptr;
1687 }
1688
1689 void InstanceKlass::call_class_initializer(TRAPS) {
1690 if (ReplayCompiles &&
1691 (ReplaySuppressInitializers == 1 ||
1692 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1693 // Hide the existence of the initializer for the purpose of replaying the compile
1694 return;
1695 }
1696
1697 #if INCLUDE_CDS
1698 // This is needed to ensure the consistency of the archived heap objects.
1699 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1700 AOTClassInitializer::call_runtime_setup(THREAD, this);
1701 return;
1702 } else if (has_archived_enum_objs()) {
1703 assert(is_shared(), "must be");
1704 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1705 if (initialized) {
1706 return;
1707 }
1708 }
1709 #endif
1710
1711 methodHandle h_method(THREAD, class_initializer());
1712 assert(!is_initialized(), "we cannot initialize twice");
1713
1714 #if 0
1715 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1716 int init_id = log_class_init(THREAD, this);
1717 if (h_method() != nullptr) {
1718 JavaCallArguments args; // No arguments
1719 JavaValue result(T_VOID);
1720 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1721 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1722
1723 elapsedTimer timer;
1724 {
1725 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1726 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1727
1728 timer.start();
1729 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1730 timer.stop();
1731 }
1732
1733 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1734
1735 jlong bc_executed = (bc_end - bc_start);
1736 if (UsePerfData && outer == nullptr) { // outermost clinit
1737 THREAD->inc_clinit_bc_counter_value(bc_executed);
1738 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1739 }
1740
1741 THREAD->set_class_being_initialized(outer);
1742
1743 LogStreamHandle(Debug, init) log;
1744 if (log.is_enabled()) {
1745 ResourceMark rm(THREAD);
1746 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1747 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1748 if (CountBytecodes || CountBytecodesPerThread) {
1749 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1750 }
1751 name()->print_value_on(&log);
1752 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1753 p2i(THREAD), THREAD->name(), p2i(this));
1754 }
1755 }
1756 LogTarget(Info, class, init) lt;
1757 if (lt.is_enabled()) {
1758 ResourceMark rm(THREAD);
1759 LogStream ls(lt);
1760 ls.print("%d Initialized ", init_id);
1761 name()->print_value_on(&ls);
1762 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1763 h_method() == nullptr ? "(no method)" : "", p2i(this),
1764 THREAD->name());
1765 }
1766 #else
1767 LogTarget(Info, class, init) lt;
1768 if (lt.is_enabled()) {
1769 ResourceMark rm(THREAD);
1770 LogStream ls(lt);
1771 ls.print("%d Initializing ", call_class_initializer_counter++);
1772 name()->print_value_on(&ls);
1773 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1774 h_method() == nullptr ? "(no method)" : "", p2i(this),
1775 THREAD->name());
1776 }
1777 if (h_method() != nullptr) {
1778 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1779 JavaCallArguments args; // No arguments
1780 JavaValue result(T_VOID);
1781 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1782 }
1783 #endif
1784 }
1785
1786 // If a class that implements this interface is initialized, is the JVM required
1787 // to first execute a <clinit> method declared in this interface,
1788 // or (if also_check_supers==true) any of the super types of this interface?
1789 //
1790 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1791 // an interface, then let SC be its superclass and let SI1, ..., SIn
1792 // be all superinterfaces of C (whether direct or indirect) that
1793 // declare at least one non-abstract, non-static method.
1794 //
1795 // So when an interface is initialized, it does not look at its
1796 // supers. But a proper class will ensure that all of its supers have
1797 // run their <clinit> methods, except that it disregards interfaces
1798 // that lack a non-static concrete method (i.e., a default method).
1799 // Therefore, you should probably call this method only when the
1800 // current class is a super of some proper class, not an interface.
1801 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1802 assert(is_interface(), "must be");
1803
1804 if (!has_nonstatic_concrete_methods()) {
1805 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1806 return false;
1807 }
1808
1809 // JVMS 5.5. Initialization
1810 // ...If C is an interface that declares a non-abstract,
1811 // non-static method, the initialization of a class that
1812 // implements C directly or indirectly.
1813 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1814 return true;
1815 }
1816 if (also_check_supers) {
1817 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1818 for (int i = 0; i < all_ifs->length(); ++i) {
1819 InstanceKlass* super_intf = all_ifs->at(i);
1820 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1821 return true;
1822 }
1823 }
1824 }
1825 return false;
1826 }
1827
1828 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1829 InterpreterOopMap* entry_for) {
1830 // Lazily create the _oop_map_cache at first request.
1831 // Load_acquire is needed to safely get instance published with CAS by another thread.
1832 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1833 if (oop_map_cache == nullptr) {
1834 // Try to install new instance atomically.
1835 oop_map_cache = new OopMapCache();
1836 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1837 if (other != nullptr) {
1838 // Someone else managed to install before us, ditch local copy and use the existing one.
1839 delete oop_map_cache;
1840 oop_map_cache = other;
1841 }
1842 }
1843 // _oop_map_cache is constant after init; lookup below does its own locking.
1844 oop_map_cache->lookup(method, bci, entry_for);
1845 }
1846
1847 bool InstanceKlass::contains_field_offset(int offset) {
1848 fieldDescriptor fd;
1849 return find_field_from_offset(offset, false, &fd);
1850 }
1851
1852 FieldInfo InstanceKlass::field(int index) const {
1853 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1854 if (fs.index() == index) {
1855 return fs.to_FieldInfo();
1856 }
1857 }
1858 fatal("Field not found");
1859 return FieldInfo();
1860 }
1861
1862 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1863 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1864 Symbol* f_name = fs.name();
1865 Symbol* f_sig = fs.signature();
1866 if (f_name == name && f_sig == sig) {
1867 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1868 return true;
1869 }
1870 }
1871 return false;
1872 }
1873
1874
1875 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1876 const int n = local_interfaces()->length();
1877 for (int i = 0; i < n; i++) {
1878 Klass* intf1 = local_interfaces()->at(i);
1879 assert(intf1->is_interface(), "just checking type");
1880 // search for field in current interface
1881 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1882 assert(fd->is_static(), "interface field must be static");
1883 return intf1;
1884 }
1885 // search for field in direct superinterfaces
1886 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1887 if (intf2 != nullptr) return intf2;
1888 }
1889 // otherwise field lookup fails
1890 return nullptr;
1891 }
1892
1893
1894 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1895 // search order according to newest JVM spec (5.4.3.2, p.167).
1896 // 1) search for field in current klass
1897 if (find_local_field(name, sig, fd)) {
1898 return const_cast<InstanceKlass*>(this);
1899 }
1900 // 2) search for field recursively in direct superinterfaces
1901 { Klass* intf = find_interface_field(name, sig, fd);
1902 if (intf != nullptr) return intf;
1903 }
1904 // 3) apply field lookup recursively if superclass exists
1905 { Klass* supr = super();
1906 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1907 }
1908 // 4) otherwise field lookup fails
1909 return nullptr;
1910 }
1911
1912
1913 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1914 // search order according to newest JVM spec (5.4.3.2, p.167).
1915 // 1) search for field in current klass
1916 if (find_local_field(name, sig, fd)) {
1917 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1918 }
1919 // 2) search for field recursively in direct superinterfaces
1920 if (is_static) {
1921 Klass* intf = find_interface_field(name, sig, fd);
1922 if (intf != nullptr) return intf;
1923 }
1924 // 3) apply field lookup recursively if superclass exists
1925 { Klass* supr = super();
1926 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1927 }
1928 // 4) otherwise field lookup fails
1929 return nullptr;
1930 }
1931
1932
1933 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1934 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1935 if (fs.offset() == offset) {
1936 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1937 if (fd->is_static() == is_static) return true;
1938 }
1939 }
1940 return false;
1941 }
1942
1943
1944 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1945 Klass* klass = const_cast<InstanceKlass*>(this);
1946 while (klass != nullptr) {
1947 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1948 return true;
1949 }
1950 klass = klass->super();
1951 }
1952 return false;
1953 }
1954
1955
1956 void InstanceKlass::methods_do(void f(Method* method)) {
1957 // Methods aren't stable until they are loaded. This can be read outside
1958 // a lock through the ClassLoaderData for profiling
1959 // Redefined scratch classes are on the list and need to be cleaned
1960 if (!is_loaded() && !is_scratch_class()) {
1961 return;
1962 }
1963
1964 int len = methods()->length();
1965 for (int index = 0; index < len; index++) {
1966 Method* m = methods()->at(index);
1967 assert(m->is_method(), "must be method");
1968 f(m);
1969 }
1970 }
1971
1972
1973 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1974 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1975 if (fs.access_flags().is_static()) {
1976 fieldDescriptor& fd = fs.field_descriptor();
1977 cl->do_field(&fd);
1978 }
1979 }
1980 }
1981
1982
1983 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1984 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1985 if (fs.access_flags().is_static()) {
1986 fieldDescriptor& fd = fs.field_descriptor();
1987 f(&fd, mirror, CHECK);
1988 }
1989 }
1990 }
1991
1992 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1993 InstanceKlass* super = superklass();
1994 if (super != nullptr) {
1995 super->do_nonstatic_fields(cl);
1996 }
1997 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1998 fieldDescriptor& fd = fs.field_descriptor();
1999 if (!fd.is_static()) {
2000 cl->do_field(&fd);
2001 }
2002 }
2003 }
2004
2005 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2006 return a->offset() - b->offset();
2007 }
2008
2009 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2010 InstanceKlass* super = superklass();
2011 if (super != nullptr) {
2012 super->print_nonstatic_fields(cl);
2013 }
2014 ResourceMark rm;
2015 // In DebugInfo nonstatic fields are sorted by offset.
2016 GrowableArray<FieldInfo> fields_sorted;
2017 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2018 if (!fs.access_flags().is_static()) {
2019 fields_sorted.push(fs.to_FieldInfo());
2020 }
2021 }
2022 int length = fields_sorted.length();
2023 if (length > 0) {
2024 fields_sorted.sort(compare_fields_by_offset);
2025 fieldDescriptor fd;
2026 for (int i = 0; i < length; i++) {
2027 fd.reinitialize(this, fields_sorted.at(i));
2028 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2029 cl->do_field(&fd);
2030 }
2031 }
2032 }
2033
2034 #ifdef ASSERT
2035 static int linear_search(const Array<Method*>* methods,
2036 const Symbol* name,
2037 const Symbol* signature) {
2038 const int len = methods->length();
2039 for (int index = 0; index < len; index++) {
2040 const Method* const m = methods->at(index);
2041 assert(m->is_method(), "must be method");
2042 if (m->signature() == signature && m->name() == name) {
2043 return index;
2044 }
2045 }
2046 return -1;
2047 }
2048 #endif
2049
2050 bool InstanceKlass::_disable_method_binary_search = false;
2051
2052 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2053 int len = methods->length();
2054 int l = 0;
2055 int h = len - 1;
2056 while (l <= h) {
2057 Method* m = methods->at(l);
2058 if (m->name() == name) {
2059 return l;
2060 }
2061 l++;
2062 }
2063 return -1;
2064 }
2065
2066 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2067 if (_disable_method_binary_search) {
2068 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2069 // At the final stage of dynamic dumping, the methods array may not be sorted
2070 // by ascending addresses of their names, so we can't use binary search anymore.
2071 // However, methods with the same name are still laid out consecutively inside the
2072 // methods array, so let's look for the first one that matches.
2073 return linear_search(methods, name);
2074 }
2075
2076 int len = methods->length();
2077 int l = 0;
2078 int h = len - 1;
2079
2080 // methods are sorted by ascending addresses of their names, so do binary search
2081 while (l <= h) {
2082 int mid = (l + h) >> 1;
2083 Method* m = methods->at(mid);
2084 assert(m->is_method(), "must be method");
2085 int res = m->name()->fast_compare(name);
2086 if (res == 0) {
2087 return mid;
2088 } else if (res < 0) {
2089 l = mid + 1;
2090 } else {
2091 h = mid - 1;
2092 }
2093 }
2094 return -1;
2095 }
2096
2097 // find_method looks up the name/signature in the local methods array
2098 Method* InstanceKlass::find_method(const Symbol* name,
2099 const Symbol* signature) const {
2100 return find_method_impl(name, signature,
2101 OverpassLookupMode::find,
2102 StaticLookupMode::find,
2103 PrivateLookupMode::find);
2104 }
2105
2106 Method* InstanceKlass::find_method_impl(const Symbol* name,
2107 const Symbol* signature,
2108 OverpassLookupMode overpass_mode,
2109 StaticLookupMode static_mode,
2110 PrivateLookupMode private_mode) const {
2111 return InstanceKlass::find_method_impl(methods(),
2112 name,
2113 signature,
2114 overpass_mode,
2115 static_mode,
2116 private_mode);
2117 }
2118
2119 // find_instance_method looks up the name/signature in the local methods array
2120 // and skips over static methods
2121 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2122 const Symbol* name,
2123 const Symbol* signature,
2124 PrivateLookupMode private_mode) {
2125 Method* const meth = InstanceKlass::find_method_impl(methods,
2126 name,
2127 signature,
2128 OverpassLookupMode::find,
2129 StaticLookupMode::skip,
2130 private_mode);
2131 assert(((meth == nullptr) || !meth->is_static()),
2132 "find_instance_method should have skipped statics");
2133 return meth;
2134 }
2135
2136 // find_instance_method looks up the name/signature in the local methods array
2137 // and skips over static methods
2138 Method* InstanceKlass::find_instance_method(const Symbol* name,
2139 const Symbol* signature,
2140 PrivateLookupMode private_mode) const {
2141 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2142 }
2143
2144 // Find looks up the name/signature in the local methods array
2145 // and filters on the overpass, static and private flags
2146 // This returns the first one found
2147 // note that the local methods array can have up to one overpass, one static
2148 // and one instance (private or not) with the same name/signature
2149 Method* InstanceKlass::find_local_method(const Symbol* name,
2150 const Symbol* signature,
2151 OverpassLookupMode overpass_mode,
2152 StaticLookupMode static_mode,
2153 PrivateLookupMode private_mode) const {
2154 return InstanceKlass::find_method_impl(methods(),
2155 name,
2156 signature,
2157 overpass_mode,
2158 static_mode,
2159 private_mode);
2160 }
2161
2162 // Find looks up the name/signature in the local methods array
2163 // and filters on the overpass, static and private flags
2164 // This returns the first one found
2165 // note that the local methods array can have up to one overpass, one static
2166 // and one instance (private or not) with the same name/signature
2167 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2168 const Symbol* name,
2169 const Symbol* signature,
2170 OverpassLookupMode overpass_mode,
2171 StaticLookupMode static_mode,
2172 PrivateLookupMode private_mode) {
2173 return InstanceKlass::find_method_impl(methods,
2174 name,
2175 signature,
2176 overpass_mode,
2177 static_mode,
2178 private_mode);
2179 }
2180
2181 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2182 const Symbol* name,
2183 const Symbol* signature) {
2184 return InstanceKlass::find_method_impl(methods,
2185 name,
2186 signature,
2187 OverpassLookupMode::find,
2188 StaticLookupMode::find,
2189 PrivateLookupMode::find);
2190 }
2191
2192 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2193 const Symbol* name,
2194 const Symbol* signature,
2195 OverpassLookupMode overpass_mode,
2196 StaticLookupMode static_mode,
2197 PrivateLookupMode private_mode) {
2198 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2199 return hit >= 0 ? methods->at(hit): nullptr;
2200 }
2201
2202 // true if method matches signature and conforms to skipping_X conditions.
2203 static bool method_matches(const Method* m,
2204 const Symbol* signature,
2205 bool skipping_overpass,
2206 bool skipping_static,
2207 bool skipping_private) {
2208 return ((m->signature() == signature) &&
2209 (!skipping_overpass || !m->is_overpass()) &&
2210 (!skipping_static || !m->is_static()) &&
2211 (!skipping_private || !m->is_private()));
2212 }
2213
2214 // Used directly for default_methods to find the index into the
2215 // default_vtable_indices, and indirectly by find_method
2216 // find_method_index looks in the local methods array to return the index
2217 // of the matching name/signature. If, overpass methods are being ignored,
2218 // the search continues to find a potential non-overpass match. This capability
2219 // is important during method resolution to prefer a static method, for example,
2220 // over an overpass method.
2221 // There is the possibility in any _method's array to have the same name/signature
2222 // for a static method, an overpass method and a local instance method
2223 // To correctly catch a given method, the search criteria may need
2224 // to explicitly skip the other two. For local instance methods, it
2225 // is often necessary to skip private methods
2226 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2227 const Symbol* name,
2228 const Symbol* signature,
2229 OverpassLookupMode overpass_mode,
2230 StaticLookupMode static_mode,
2231 PrivateLookupMode private_mode) {
2232 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2233 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2234 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2235 const int hit = quick_search(methods, name);
2236 if (hit != -1) {
2237 const Method* const m = methods->at(hit);
2238
2239 // Do linear search to find matching signature. First, quick check
2240 // for common case, ignoring overpasses if requested.
2241 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2242 return hit;
2243 }
2244
2245 // search downwards through overloaded methods
2246 int i;
2247 for (i = hit - 1; i >= 0; --i) {
2248 const Method* const m = methods->at(i);
2249 assert(m->is_method(), "must be method");
2250 if (m->name() != name) {
2251 break;
2252 }
2253 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2254 return i;
2255 }
2256 }
2257 // search upwards
2258 for (i = hit + 1; i < methods->length(); ++i) {
2259 const Method* const m = methods->at(i);
2260 assert(m->is_method(), "must be method");
2261 if (m->name() != name) {
2262 break;
2263 }
2264 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2265 return i;
2266 }
2267 }
2268 // not found
2269 #ifdef ASSERT
2270 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2271 linear_search(methods, name, signature);
2272 assert(-1 == index, "binary search should have found entry %d", index);
2273 #endif
2274 }
2275 return -1;
2276 }
2277
2278 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2279 return find_method_by_name(methods(), name, end);
2280 }
2281
2282 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2283 const Symbol* name,
2284 int* end_ptr) {
2285 assert(end_ptr != nullptr, "just checking");
2286 int start = quick_search(methods, name);
2287 int end = start + 1;
2288 if (start != -1) {
2289 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2290 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2291 *end_ptr = end;
2292 return start;
2293 }
2294 return -1;
2295 }
2296
2297 // uncached_lookup_method searches both the local class methods array and all
2298 // superclasses methods arrays, skipping any overpass methods in superclasses,
2299 // and possibly skipping private methods.
2300 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2301 const Symbol* signature,
2302 OverpassLookupMode overpass_mode,
2303 PrivateLookupMode private_mode) const {
2304 OverpassLookupMode overpass_local_mode = overpass_mode;
2305 const Klass* klass = this;
2306 while (klass != nullptr) {
2307 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2308 signature,
2309 overpass_local_mode,
2310 StaticLookupMode::find,
2311 private_mode);
2312 if (method != nullptr) {
2313 return method;
2314 }
2315 klass = klass->super();
2316 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2317 }
2318 return nullptr;
2319 }
2320
2321 #ifdef ASSERT
2322 // search through class hierarchy and return true if this class or
2323 // one of the superclasses was redefined
2324 bool InstanceKlass::has_redefined_this_or_super() const {
2325 const Klass* klass = this;
2326 while (klass != nullptr) {
2327 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2328 return true;
2329 }
2330 klass = klass->super();
2331 }
2332 return false;
2333 }
2334 #endif
2335
2336 // lookup a method in the default methods list then in all transitive interfaces
2337 // Do NOT return private or static methods
2338 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2339 Symbol* signature) const {
2340 Method* m = nullptr;
2341 if (default_methods() != nullptr) {
2342 m = find_method(default_methods(), name, signature);
2343 }
2344 // Look up interfaces
2345 if (m == nullptr) {
2346 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2347 }
2348 return m;
2349 }
2350
2351 // lookup a method in all the interfaces that this class implements
2352 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2353 // They should only be found in the initial InterfaceMethodRef
2354 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2355 Symbol* signature,
2356 DefaultsLookupMode defaults_mode) const {
2357 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2358 int num_ifs = all_ifs->length();
2359 InstanceKlass *ik = nullptr;
2360 for (int i = 0; i < num_ifs; i++) {
2361 ik = all_ifs->at(i);
2362 Method* m = ik->lookup_method(name, signature);
2363 if (m != nullptr && m->is_public() && !m->is_static() &&
2364 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2365 return m;
2366 }
2367 }
2368 return nullptr;
2369 }
2370
2371 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2372 :_st(st), _verbose(verbose) {
2373 ResourceMark rm;
2374 _st->print("%-18s ", "KlassAddr");
2375 _st->print("%-4s ", "Size");
2376 _st->print("%-20s ", "State");
2377 _st->print("%-7s ", "Flags");
2378 _st->print("%-5s ", "ClassName");
2379 _st->cr();
2380 }
2381
2382 void PrintClassClosure::do_klass(Klass* k) {
2383 ResourceMark rm;
2384 // klass pointer
2385 _st->print(PTR_FORMAT " ", p2i(k));
2386 // klass size
2387 _st->print("%4d ", k->size());
2388 // initialization state
2389 if (k->is_instance_klass()) {
2390 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2391 } else {
2392 _st->print("%-20s ","");
2393 }
2394 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2395 char buf[10];
2396 int i = 0;
2397 if (k->has_finalizer()) buf[i++] = 'F';
2398 if (k->is_instance_klass()) {
2399 InstanceKlass* ik = InstanceKlass::cast(k);
2400 if (ik->has_final_method()) buf[i++] = 'f';
2401 if (ik->is_rewritten()) buf[i++] = 'W';
2402 if (ik->is_contended()) buf[i++] = 'C';
2403 if (ik->has_been_redefined()) buf[i++] = 'R';
2404 if (ik->is_shared()) buf[i++] = 'S';
2405 }
2406 buf[i++] = '\0';
2407 _st->print("%-7s ", buf);
2408 // klass name
2409 _st->print("%-5s ", k->external_name());
2410 // end
2411 _st->cr();
2412 if (_verbose) {
2413 k->print_on(_st);
2414 }
2415 }
2416
2417 /* jni_id_for for jfieldIds only */
2418 JNIid* InstanceKlass::jni_id_for(int offset) {
2419 MutexLocker ml(JfieldIdCreation_lock);
2420 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2421 if (probe == nullptr) {
2422 // Allocate new static field identifier
2423 probe = new JNIid(this, offset, jni_ids());
2424 set_jni_ids(probe);
2425 }
2426 return probe;
2427 }
2428
2429 u2 InstanceKlass::enclosing_method_data(int offset) const {
2430 const Array<jushort>* const inner_class_list = inner_classes();
2431 if (inner_class_list == nullptr) {
2432 return 0;
2433 }
2434 const int length = inner_class_list->length();
2435 if (length % inner_class_next_offset == 0) {
2436 return 0;
2437 }
2438 const int index = length - enclosing_method_attribute_size;
2439 assert(offset < enclosing_method_attribute_size, "invalid offset");
2440 return inner_class_list->at(index + offset);
2441 }
2442
2443 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2444 u2 method_index) {
2445 Array<jushort>* inner_class_list = inner_classes();
2446 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2447 int length = inner_class_list->length();
2448 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2449 int index = length - enclosing_method_attribute_size;
2450 inner_class_list->at_put(
2451 index + enclosing_method_class_index_offset, class_index);
2452 inner_class_list->at_put(
2453 index + enclosing_method_method_index_offset, method_index);
2454 }
2455 }
2456
2457 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2458 if (method->is_old() && !method->is_obsolete()) {
2459 // If the method passed in is old (but not obsolete), use the current version.
2460 method = method_with_idnum((int)idnum);
2461 assert(method != nullptr, "old and but not obsolete, so should exist");
2462 }
2463 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2464 Atomic::release_store(&jmeths[idnum + 1], new_id);
2465 return new_id;
2466 }
2467
2468 // Lookup or create a jmethodID.
2469 // This code is called by the VMThread and JavaThreads so the
2470 // locking has to be done very carefully to avoid deadlocks
2471 // and/or other cache consistency problems.
2472 //
2473 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2474 Method* method = method_h();
2475 int idnum = method->method_idnum();
2476 jmethodID* jmeths = methods_jmethod_ids_acquire();
2477
2478 // We use a double-check locking idiom here because this cache is
2479 // performance sensitive. In the normal system, this cache only
2480 // transitions from null to non-null which is safe because we use
2481 // release_set_methods_jmethod_ids() to advertise the new cache.
2482 // A partially constructed cache should never be seen by a racing
2483 // thread. We also use release_store() to save a new jmethodID
2484 // in the cache so a partially constructed jmethodID should never be
2485 // seen either. Cache reads of existing jmethodIDs proceed without a
2486 // lock, but cache writes of a new jmethodID requires uniqueness and
2487 // creation of the cache itself requires no leaks so a lock is
2488 // acquired in those two cases.
2489 //
2490 // If the RedefineClasses() API has been used, then this cache grows
2491 // in the redefinition safepoint.
2492
2493 if (jmeths == nullptr) {
2494 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2495 jmeths = methods_jmethod_ids_acquire();
2496 // Still null?
2497 if (jmeths == nullptr) {
2498 size_t size = idnum_allocated_count();
2499 assert(size > (size_t)idnum, "should already have space");
2500 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2501 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2502 // cache size is stored in element[0], other elements offset by one
2503 jmeths[0] = (jmethodID)size;
2504 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2505
2506 // publish jmeths
2507 release_set_methods_jmethod_ids(jmeths);
2508 return new_id;
2509 }
2510 }
2511
2512 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2513 if (id == nullptr) {
2514 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2515 id = jmeths[idnum + 1];
2516 // Still null?
2517 if (id == nullptr) {
2518 return update_jmethod_id(jmeths, method, idnum);
2519 }
2520 }
2521 return id;
2522 }
2523
2524 void InstanceKlass::update_methods_jmethod_cache() {
2525 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2526 jmethodID* cache = _methods_jmethod_ids;
2527 if (cache != nullptr) {
2528 size_t size = idnum_allocated_count();
2529 size_t old_size = (size_t)cache[0];
2530 if (old_size < size + 1) {
2531 // Allocate a larger one and copy entries to the new one.
2532 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2533 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2534 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2535 // The cache size is stored in element[0]; the other elements are offset by one.
2536 new_cache[0] = (jmethodID)size;
2537
2538 for (int i = 1; i <= (int)old_size; i++) {
2539 new_cache[i] = cache[i];
2540 }
2541 _methods_jmethod_ids = new_cache;
2542 FREE_C_HEAP_ARRAY(jmethodID, cache);
2543 }
2544 }
2545 }
2546
2547 // Figure out how many jmethodIDs haven't been allocated, and make
2548 // sure space for them is pre-allocated. This makes getting all
2549 // method ids much, much faster with classes with more than 8
2550 // methods, and has a *substantial* effect on performance with jvmti
2551 // code that loads all jmethodIDs for all classes.
2552 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2553 int new_jmeths = 0;
2554 int length = methods()->length();
2555 for (int index = start_offset; index < length; index++) {
2556 Method* m = methods()->at(index);
2557 jmethodID id = m->find_jmethod_id_or_null();
2558 if (id == nullptr) {
2559 new_jmeths++;
2560 }
2561 }
2562 if (new_jmeths != 0) {
2563 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2564 }
2565 }
2566
2567 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2568 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2569 int idnum = method->method_idnum();
2570 jmethodID* jmeths = methods_jmethod_ids_acquire();
2571 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2572 }
2573
2574 inline DependencyContext InstanceKlass::dependencies() {
2575 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2576 return dep_context;
2577 }
2578
2579 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2580 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2581 }
2582
2583 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2584 assert_lock_strong(CodeCache_lock);
2585 dependencies().add_dependent_nmethod(nm);
2586 }
2587
2588 void InstanceKlass::clean_dependency_context() {
2589 dependencies().clean_unloading_dependents();
2590 }
2591
2592 #ifndef PRODUCT
2593 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2594 dependencies().print_dependent_nmethods(verbose);
2595 }
2596
2597 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2598 return dependencies().is_dependent_nmethod(nm);
2599 }
2600 #endif //PRODUCT
2601
2602 void InstanceKlass::clean_weak_instanceklass_links() {
2603 clean_implementors_list();
2604 clean_method_data();
2605 }
2606
2607 void InstanceKlass::clean_implementors_list() {
2608 assert(is_loader_alive(), "this klass should be live");
2609 if (is_interface()) {
2610 assert (ClassUnloading, "only called for ClassUnloading");
2611 for (;;) {
2612 // Use load_acquire due to competing with inserts
2613 InstanceKlass* volatile* iklass = adr_implementor();
2614 assert(iklass != nullptr, "Klass must not be null");
2615 InstanceKlass* impl = Atomic::load_acquire(iklass);
2616 if (impl != nullptr && !impl->is_loader_alive()) {
2617 // null this field, might be an unloaded instance klass or null
2618 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2619 // Successfully unlinking implementor.
2620 if (log_is_enabled(Trace, class, unload)) {
2621 ResourceMark rm;
2622 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2623 }
2624 return;
2625 }
2626 } else {
2627 return;
2628 }
2629 }
2630 }
2631 }
2632
2633 void InstanceKlass::clean_method_data() {
2634 for (int m = 0; m < methods()->length(); m++) {
2635 MethodData* mdo = methods()->at(m)->method_data();
2636 if (mdo != nullptr) {
2637 mdo->clean_method_data(/*always_clean*/false);
2638 }
2639 }
2640 }
2641
2642 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2643 Klass::metaspace_pointers_do(it);
2644
2645 if (log_is_enabled(Trace, aot)) {
2646 ResourceMark rm;
2647 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2648 }
2649
2650 it->push(&_annotations);
2651 it->push((Klass**)&_array_klasses);
2652 if (!is_rewritten()) {
2653 it->push(&_constants, MetaspaceClosure::_writable);
2654 } else {
2655 it->push(&_constants);
2656 }
2657 it->push(&_inner_classes);
2658 #if INCLUDE_JVMTI
2659 it->push(&_previous_versions);
2660 #endif
2661 #if INCLUDE_CDS
2662 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2663 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2664 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2665 // The length check on the _methods is necessary because classes which don't have any
2666 // methods share the Universe::_the_empty_method_array which is in the RO region.
2667 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2668 // To handle jsr bytecode, new Method* maybe stored into _methods
2669 it->push(&_methods, MetaspaceClosure::_writable);
2670 } else {
2671 #endif
2672 it->push(&_methods);
2673 #if INCLUDE_CDS
2674 }
2675 #endif
2676 it->push(&_default_methods);
2677 it->push(&_local_interfaces);
2678 it->push(&_transitive_interfaces);
2679 it->push(&_method_ordering);
2680 if (!is_rewritten()) {
2681 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2682 } else {
2683 it->push(&_default_vtable_indices);
2684 }
2685
2686 it->push(&_fieldinfo_stream);
2687 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2688 it->push(&_fields_status, MetaspaceClosure::_writable);
2689
2690 if (itable_length() > 0) {
2691 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2692 int method_table_offset_in_words = ioe->offset()/wordSize;
2693 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2694
2695 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2696 / itableOffsetEntry::size();
2697
2698 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2699 if (ioe->interface_klass() != nullptr) {
2700 it->push(ioe->interface_klass_addr());
2701 itableMethodEntry* ime = ioe->first_method_entry(this);
2702 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2703 for (int index = 0; index < n; index ++) {
2704 it->push(ime[index].method_addr());
2705 }
2706 }
2707 }
2708 }
2709
2710 it->push(&_nest_host);
2711 it->push(&_nest_members);
2712 it->push(&_permitted_subclasses);
2713 it->push(&_record_components);
2714 }
2715
2716 #if INCLUDE_CDS
2717 void InstanceKlass::remove_unshareable_info() {
2718 if (is_linked()) {
2719 assert(can_be_verified_at_dumptime(), "must be");
2720 // Remember this so we can avoid walking the hierarchy at runtime.
2721 set_verified_at_dump_time();
2722 }
2723 _misc_flags.set_has_init_deps_processed(false);
2724
2725 _misc_flags.set_has_init_deps_processed(false);
2726
2727 Klass::remove_unshareable_info();
2728
2729 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2730 // Classes are attempted to link during dumping and may fail,
2731 // but these classes are still in the dictionary and class list in CLD.
2732 // If the class has failed verification, there is nothing else to remove.
2733 return;
2734 }
2735
2736 // Reset to the 'allocated' state to prevent any premature accessing to
2737 // a shared class at runtime while the class is still being loaded and
2738 // restored. A class' init_state is set to 'loaded' at runtime when it's
2739 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2740 _init_state = allocated;
2741
2742 { // Otherwise this needs to take out the Compile_lock.
2743 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2744 init_implementor();
2745 }
2746
2747 // Call remove_unshareable_info() on other objects that belong to this class, except
2748 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2749 // ArchiveBuilder::make_klasses_shareable(),
2750
2751 for (int i = 0; i < methods()->length(); i++) {
2752 Method* m = methods()->at(i);
2753 m->remove_unshareable_info();
2754 }
2755
2756 // do array classes also.
2757 if (array_klasses() != nullptr) {
2758 array_klasses()->remove_unshareable_info();
2759 }
2760
2761 // These are not allocated from metaspace. They are safe to set to null.
2762 _source_debug_extension = nullptr;
2763 _dep_context = nullptr;
2764 _osr_nmethods_head = nullptr;
2765 #if INCLUDE_JVMTI
2766 _breakpoints = nullptr;
2767 _previous_versions = nullptr;
2768 _cached_class_file = nullptr;
2769 _jvmti_cached_class_field_map = nullptr;
2770 #endif
2771
2772 _init_thread = nullptr;
2773 _methods_jmethod_ids = nullptr;
2774 _jni_ids = nullptr;
2775 _oop_map_cache = nullptr;
2776 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2777 // keep _nest_host
2778 } else {
2779 // clear _nest_host to ensure re-load at runtime
2780 _nest_host = nullptr;
2781 }
2782 init_shared_package_entry();
2783 _dep_context_last_cleaned = 0;
2784 DEBUG_ONLY(_shared_class_load_count = 0);
2785
2786 remove_unshareable_flags();
2787 }
2788
2789 void InstanceKlass::remove_unshareable_flags() {
2790 // clear all the flags/stats that shouldn't be in the archived version
2791 assert(!is_scratch_class(), "must be");
2792 assert(!has_been_redefined(), "must be");
2793 #if INCLUDE_JVMTI
2794 set_is_being_redefined(false);
2795 #endif
2796 set_has_resolved_methods(false);
2797 }
2798
2799 void InstanceKlass::remove_java_mirror() {
2800 Klass::remove_java_mirror();
2801
2802 // do array classes also.
2803 if (array_klasses() != nullptr) {
2804 array_klasses()->remove_java_mirror();
2805 }
2806 }
2807
2808 void InstanceKlass::init_shared_package_entry() {
2809 assert(CDSConfig::is_dumping_archive(), "must be");
2810 #if !INCLUDE_CDS_JAVA_HEAP
2811 _package_entry = nullptr;
2812 #else
2813 if (CDSConfig::is_dumping_full_module_graph()) {
2814 if (defined_by_other_loaders()) {
2815 _package_entry = nullptr;
2816 } else {
2817 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2818 }
2819 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2820 CDSConfig::is_using_full_module_graph() &&
2821 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2822 // _package_entry is an archived package in the base archive. Leave it as is.
2823 } else {
2824 _package_entry = nullptr;
2825 }
2826 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2827 #endif
2828 }
2829
2830 void InstanceKlass::compute_has_loops_flag_for_methods() {
2831 Array<Method*>* methods = this->methods();
2832 for (int index = 0; index < methods->length(); ++index) {
2833 Method* m = methods->at(index);
2834 if (!m->is_overpass()) { // work around JDK-8305771
2835 m->compute_has_loops_flag();
2836 }
2837 }
2838 }
2839
2840 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2841 PackageEntry* pkg_entry, TRAPS) {
2842 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2843 // before the InstanceKlass is added to the SystemDictionary. Make
2844 // sure the current state is <loaded.
2845 assert(!is_loaded(), "invalid init state");
2846 assert(!shared_loading_failed(), "Must not try to load failed class again");
2847 set_package(loader_data, pkg_entry, CHECK);
2848 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2849
2850 Array<Method*>* methods = this->methods();
2851 int num_methods = methods->length();
2852 for (int index = 0; index < num_methods; ++index) {
2853 methods->at(index)->restore_unshareable_info(CHECK);
2854 }
2855 #if INCLUDE_JVMTI
2856 if (JvmtiExport::has_redefined_a_class()) {
2857 // Reinitialize vtable because RedefineClasses may have changed some
2858 // entries in this vtable for super classes so the CDS vtable might
2859 // point to old or obsolete entries. RedefineClasses doesn't fix up
2860 // vtables in the shared system dictionary, only the main one.
2861 // It also redefines the itable too so fix that too.
2862 // First fix any default methods that point to a super class that may
2863 // have been redefined.
2864 bool trace_name_printed = false;
2865 adjust_default_methods(&trace_name_printed);
2866 if (verified_at_dump_time()) {
2867 // Initialize vtable and itable for classes which can be verified at dump time.
2868 // Unlinked classes such as old classes with major version < 50 cannot be verified
2869 // at dump time.
2870 vtable().initialize_vtable();
2871 itable().initialize_itable();
2872 }
2873 }
2874 #endif // INCLUDE_JVMTI
2875
2876 // restore constant pool resolved references
2877 constants()->restore_unshareable_info(CHECK);
2878
2879 if (array_klasses() != nullptr) {
2880 // To get a consistent list of classes we need MultiArray_lock to ensure
2881 // array classes aren't observed while they are being restored.
2882 RecursiveLocker rl(MultiArray_lock, THREAD);
2883 assert(this == array_klasses()->bottom_klass(), "sanity");
2884 // Array classes have null protection domain.
2885 // --> see ArrayKlass::complete_create_array_klass()
2886 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2887 }
2888
2889 // Initialize @ValueBased class annotation if not already set in the archived klass.
2890 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2891 set_is_value_based();
2892 }
2893 }
2894
2895 bool InstanceKlass::can_be_verified_at_dumptime() const {
2896 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2897 return true;
2898 }
2899
2900 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2901 // This is a class that was dumped into the base archive, so we know
2902 // it was verified at dump time.
2903 return true;
2904 }
2905
2906 // Check if a class or any of its supertypes has a version older than 50.
2907 // CDS will not perform verification of old classes during dump time because
2908 // without changing the old verifier, the verification constraint cannot be
2909 // retrieved during dump time.
2910 // Verification of archived old classes will be performed during run time.
2911 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2912 return false;
2913 }
2914 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2915 return false;
2916 }
2917 Array<InstanceKlass*>* interfaces = local_interfaces();
2918 int len = interfaces->length();
2919 for (int i = 0; i < len; i++) {
2920 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2921 return false;
2922 }
2923 }
2924 return true;
2925 }
2926
2927 #endif // INCLUDE_CDS
2928
2929 #if INCLUDE_JVMTI
2930 static void clear_all_breakpoints(Method* m) {
2931 m->clear_all_breakpoints();
2932 }
2933 #endif
2934
2935 void InstanceKlass::unload_class(InstanceKlass* ik) {
2936
2937 if (ik->is_scratch_class()) {
2938 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2939 return;
2940 }
2941 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2942
2943 // Release dependencies.
2944 ik->dependencies().remove_all_dependents();
2945
2946 // notify the debugger
2947 if (JvmtiExport::should_post_class_unload()) {
2948 JvmtiExport::post_class_unload(ik);
2949 }
2950
2951 // notify ClassLoadingService of class unload
2952 ClassLoadingService::notify_class_unloaded(ik);
2953
2954 SystemDictionaryShared::handle_class_unloading(ik);
2955
2956 if (log_is_enabled(Info, class, unload)) {
2957 ResourceMark rm;
2958 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2959 }
2960
2961 Events::log_class_unloading(Thread::current(), ik);
2962
2963 #if INCLUDE_JFR
2964 assert(ik != nullptr, "invariant");
2965 EventClassUnload event;
2966 event.set_unloadedClass(ik);
2967 event.set_definingClassLoader(ik->class_loader_data());
2968 event.commit();
2969 #endif
2970 }
2971
2972 static void method_release_C_heap_structures(Method* m) {
2973 m->release_C_heap_structures();
2974 }
2975
2976 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2977 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2978 // Clean up C heap
2979 Klass::release_C_heap_structures();
2980
2981 // Deallocate and call destructors for MDO mutexes
2982 if (release_sub_metadata) {
2983 methods_do(method_release_C_heap_structures);
2984 }
2985
2986 // Deallocate oop map cache
2987 if (_oop_map_cache != nullptr) {
2988 delete _oop_map_cache;
2989 _oop_map_cache = nullptr;
2990 }
2991
2992 // Deallocate JNI identifiers for jfieldIDs
2993 JNIid::deallocate(jni_ids());
2994 set_jni_ids(nullptr);
2995
2996 jmethodID* jmeths = methods_jmethod_ids_acquire();
2997 if (jmeths != nullptr) {
2998 release_set_methods_jmethod_ids(nullptr);
2999 FreeHeap(jmeths);
3000 }
3001
3002 assert(_dep_context == nullptr,
3003 "dependencies should already be cleaned");
3004
3005 #if INCLUDE_JVMTI
3006 // Deallocate breakpoint records
3007 if (breakpoints() != nullptr) {
3008 methods_do(clear_all_breakpoints);
3009 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3010 }
3011
3012 // deallocate the cached class file
3013 if (_cached_class_file != nullptr) {
3014 os::free(_cached_class_file);
3015 _cached_class_file = nullptr;
3016 }
3017 #endif
3018
3019 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3020
3021 if (release_sub_metadata) {
3022 constants()->release_C_heap_structures();
3023 }
3024 }
3025
3026 // The constant pool is on stack if any of the methods are executing or
3027 // referenced by handles.
3028 bool InstanceKlass::on_stack() const {
3029 return _constants->on_stack();
3030 }
3031
3032 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3033 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3034 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3035
3036 // minor and major version numbers of class file
3037 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3038 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3039 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3040 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3041
3042 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3043 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3044 if (ik->constants()->version() == version) {
3045 return ik;
3046 }
3047 }
3048 return nullptr;
3049 }
3050
3051 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3052 if (array == nullptr) {
3053 _source_debug_extension = nullptr;
3054 } else {
3055 // Adding one to the attribute length in order to store a null terminator
3056 // character could cause an overflow because the attribute length is
3057 // already coded with an u4 in the classfile, but in practice, it's
3058 // unlikely to happen.
3059 assert((length+1) > length, "Overflow checking");
3060 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3061 for (int i = 0; i < length; i++) {
3062 sde[i] = array[i];
3063 }
3064 sde[length] = '\0';
3065 _source_debug_extension = sde;
3066 }
3067 }
3068
3069 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3070 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3071 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3072
3073 const char* InstanceKlass::signature_name() const {
3074
3075 // Get the internal name as a c string
3076 const char* src = (const char*) (name()->as_C_string());
3077 const int src_length = (int)strlen(src);
3078
3079 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3080
3081 // Add L as type indicator
3082 int dest_index = 0;
3083 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3084
3085 // Add the actual class name
3086 for (int src_index = 0; src_index < src_length; ) {
3087 dest[dest_index++] = src[src_index++];
3088 }
3089
3090 if (is_hidden()) { // Replace the last '+' with a '.'.
3091 for (int index = (int)src_length; index > 0; index--) {
3092 if (dest[index] == '+') {
3093 dest[index] = JVM_SIGNATURE_DOT;
3094 break;
3095 }
3096 }
3097 }
3098
3099 // Add the semicolon and the null
3100 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3101 dest[dest_index] = '\0';
3102 return dest;
3103 }
3104
3105 ModuleEntry* InstanceKlass::module() const {
3106 if (is_hidden() &&
3107 in_unnamed_package() &&
3108 class_loader_data()->has_class_mirror_holder()) {
3109 // For a non-strong hidden class defined to an unnamed package,
3110 // its (class held) CLD will not have an unnamed module created for it.
3111 // Two choices to find the correct ModuleEntry:
3112 // 1. If hidden class is within a nest, use nest host's module
3113 // 2. Find the unnamed module off from the class loader
3114 // For now option #2 is used since a nest host is not set until
3115 // after the instance class is created in jvm_lookup_define_class().
3116 if (class_loader_data()->is_boot_class_loader_data()) {
3117 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3118 } else {
3119 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3120 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3121 return java_lang_Module::module_entry(module);
3122 }
3123 }
3124
3125 // Class is in a named package
3126 if (!in_unnamed_package()) {
3127 return _package_entry->module();
3128 }
3129
3130 // Class is in an unnamed package, return its loader's unnamed module
3131 return class_loader_data()->unnamed_module();
3132 }
3133
3134 bool InstanceKlass::in_javabase_module() const {
3135 return module()->name() == vmSymbols::java_base();
3136 }
3137
3138 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3139
3140 // ensure java/ packages only loaded by boot or platform builtin loaders
3141 // not needed for shared class since CDS does not archive prohibited classes.
3142 if (!is_shared()) {
3143 check_prohibited_package(name(), loader_data, CHECK);
3144 }
3145
3146 if (is_shared() && _package_entry != nullptr) {
3147 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3148 // we can use the saved package
3149 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3150 return;
3151 } else {
3152 _package_entry = nullptr;
3153 }
3154 }
3155
3156 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3157 // it returns, so we need to decrement it when the current function exits.
3158 TempNewSymbol from_class_name =
3159 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3160
3161 Symbol* pkg_name;
3162 if (pkg_entry != nullptr) {
3163 pkg_name = pkg_entry->name();
3164 } else {
3165 pkg_name = from_class_name;
3166 }
3167
3168 if (pkg_name != nullptr && loader_data != nullptr) {
3169
3170 // Find in class loader's package entry table.
3171 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3172
3173 // If the package name is not found in the loader's package
3174 // entry table, it is an indication that the package has not
3175 // been defined. Consider it defined within the unnamed module.
3176 if (_package_entry == nullptr) {
3177
3178 if (!ModuleEntryTable::javabase_defined()) {
3179 // Before java.base is defined during bootstrapping, define all packages in
3180 // the java.base module. If a non-java.base package is erroneously placed
3181 // in the java.base module it will be caught later when java.base
3182 // is defined by ModuleEntryTable::verify_javabase_packages check.
3183 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3184 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3185 } else {
3186 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3187 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3188 }
3189
3190 // A package should have been successfully created
3191 DEBUG_ONLY(ResourceMark rm(THREAD));
3192 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3193 name()->as_C_string(), loader_data->loader_name_and_id());
3194 }
3195
3196 if (log_is_enabled(Debug, module)) {
3197 ResourceMark rm(THREAD);
3198 ModuleEntry* m = _package_entry->module();
3199 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3200 external_name(),
3201 pkg_name->as_C_string(),
3202 loader_data->loader_name_and_id(),
3203 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3204 }
3205 } else {
3206 ResourceMark rm(THREAD);
3207 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3208 external_name(),
3209 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3210 UNNAMED_MODULE);
3211 }
3212 }
3213
3214 // Function set_classpath_index ensures that for a non-null _package_entry
3215 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3216 // It then sets the classpath_index in the package entry record.
3217 //
3218 // The classpath_index field is used to find the entry on the boot loader class
3219 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3220 // in an unnamed module. It is also used to indicate (for all packages whose
3221 // classes are loaded by the boot loader) that at least one of the package's
3222 // classes has been loaded.
3223 void InstanceKlass::set_classpath_index(s2 path_index) {
3224 if (_package_entry != nullptr) {
3225 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3226 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3227 assert(path_index != -1, "Unexpected classpath_index");
3228 _package_entry->set_classpath_index(path_index);
3229 }
3230 }
3231
3232 // different versions of is_same_class_package
3233
3234 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3235 oop classloader1 = this->class_loader();
3236 PackageEntry* classpkg1 = this->package();
3237 if (class2->is_objArray_klass()) {
3238 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3239 }
3240
3241 oop classloader2;
3242 PackageEntry* classpkg2;
3243 if (class2->is_instance_klass()) {
3244 classloader2 = class2->class_loader();
3245 classpkg2 = class2->package();
3246 } else {
3247 assert(class2->is_typeArray_klass(), "should be type array");
3248 classloader2 = nullptr;
3249 classpkg2 = nullptr;
3250 }
3251
3252 // Same package is determined by comparing class loader
3253 // and package entries. Both must be the same. This rule
3254 // applies even to classes that are defined in the unnamed
3255 // package, they still must have the same class loader.
3256 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3257 return true;
3258 }
3259
3260 return false;
3261 }
3262
3263 // return true if this class and other_class are in the same package. Classloader
3264 // and classname information is enough to determine a class's package
3265 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3266 const Symbol* other_class_name) const {
3267 if (class_loader() != other_class_loader) {
3268 return false;
3269 }
3270 if (name()->fast_compare(other_class_name) == 0) {
3271 return true;
3272 }
3273
3274 {
3275 ResourceMark rm;
3276
3277 bool bad_class_name = false;
3278 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3279 if (bad_class_name) {
3280 return false;
3281 }
3282 // Check that package_from_class_name() returns null, not "", if there is no package.
3283 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3284
3285 const Symbol* const this_package_name =
3286 this->package() != nullptr ? this->package()->name() : nullptr;
3287
3288 if (this_package_name == nullptr || other_pkg == nullptr) {
3289 // One of the two doesn't have a package. Only return true if the other
3290 // one also doesn't have a package.
3291 return this_package_name == other_pkg;
3292 }
3293
3294 // Check if package is identical
3295 return this_package_name->fast_compare(other_pkg) == 0;
3296 }
3297 }
3298
3299 static bool is_prohibited_package_slow(Symbol* class_name) {
3300 // Caller has ResourceMark
3301 int length;
3302 jchar* unicode = class_name->as_unicode(length);
3303 return (length >= 5 &&
3304 unicode[0] == 'j' &&
3305 unicode[1] == 'a' &&
3306 unicode[2] == 'v' &&
3307 unicode[3] == 'a' &&
3308 unicode[4] == '/');
3309 }
3310
3311 // Only boot and platform class loaders can define classes in "java/" packages.
3312 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3313 ClassLoaderData* loader_data,
3314 TRAPS) {
3315 if (!loader_data->is_boot_class_loader_data() &&
3316 !loader_data->is_platform_class_loader_data() &&
3317 class_name != nullptr && class_name->utf8_length() >= 5) {
3318 ResourceMark rm(THREAD);
3319 bool prohibited;
3320 const u1* base = class_name->base();
3321 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3322 prohibited = is_prohibited_package_slow(class_name);
3323 } else {
3324 char* name = class_name->as_C_string();
3325 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3326 }
3327 if (prohibited) {
3328 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3329 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3330 char* name = pkg_name->as_C_string();
3331 const char* class_loader_name = loader_data->loader_name_and_id();
3332 StringUtils::replace_no_expand(name, "/", ".");
3333 const char* msg_text1 = "Class loader (instance of): ";
3334 const char* msg_text2 = " tried to load prohibited package name: ";
3335 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3336 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3337 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3338 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3339 }
3340 }
3341 return;
3342 }
3343
3344 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3345 constantPoolHandle i_cp(THREAD, constants());
3346 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3347 int ioff = iter.inner_class_info_index();
3348 if (ioff != 0) {
3349 // Check to see if the name matches the class we're looking for
3350 // before attempting to find the class.
3351 if (i_cp->klass_name_at_matches(this, ioff)) {
3352 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3353 if (this == inner_klass) {
3354 *ooff = iter.outer_class_info_index();
3355 *noff = iter.inner_name_index();
3356 return true;
3357 }
3358 }
3359 }
3360 }
3361 return false;
3362 }
3363
3364 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3365 InstanceKlass* outer_klass = nullptr;
3366 *inner_is_member = false;
3367 int ooff = 0, noff = 0;
3368 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3369 if (has_inner_classes_attr) {
3370 constantPoolHandle i_cp(THREAD, constants());
3371 if (ooff != 0) {
3372 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3373 if (!ok->is_instance_klass()) {
3374 // If the outer class is not an instance klass then it cannot have
3375 // declared any inner classes.
3376 ResourceMark rm(THREAD);
3377 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3378 Exceptions::fthrow(
3379 THREAD_AND_LOCATION,
3380 vmSymbols::java_lang_IncompatibleClassChangeError(),
3381 "%s and %s disagree on InnerClasses attribute",
3382 ok->external_name(),
3383 external_name());
3384 return nullptr;
3385 }
3386 outer_klass = InstanceKlass::cast(ok);
3387 *inner_is_member = true;
3388 }
3389 if (nullptr == outer_klass) {
3390 // It may be a local class; try for that.
3391 int encl_method_class_idx = enclosing_method_class_index();
3392 if (encl_method_class_idx != 0) {
3393 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3394 outer_klass = InstanceKlass::cast(ok);
3395 *inner_is_member = false;
3396 }
3397 }
3398 }
3399
3400 // If no inner class attribute found for this class.
3401 if (nullptr == outer_klass) return nullptr;
3402
3403 // Throws an exception if outer klass has not declared k as an inner klass
3404 // We need evidence that each klass knows about the other, or else
3405 // the system could allow a spoof of an inner class to gain access rights.
3406 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3407 return outer_klass;
3408 }
3409
3410 u2 InstanceKlass::compute_modifier_flags() const {
3411 u2 access = access_flags().as_unsigned_short();
3412
3413 // But check if it happens to be member class.
3414 InnerClassesIterator iter(this);
3415 for (; !iter.done(); iter.next()) {
3416 int ioff = iter.inner_class_info_index();
3417 // Inner class attribute can be zero, skip it.
3418 // Strange but true: JVM spec. allows null inner class refs.
3419 if (ioff == 0) continue;
3420
3421 // only look at classes that are already loaded
3422 // since we are looking for the flags for our self.
3423 Symbol* inner_name = constants()->klass_name_at(ioff);
3424 if (name() == inner_name) {
3425 // This is really a member class.
3426 access = iter.inner_access_flags();
3427 break;
3428 }
3429 }
3430 // Remember to strip ACC_SUPER bit
3431 return (access & (~JVM_ACC_SUPER));
3432 }
3433
3434 jint InstanceKlass::jvmti_class_status() const {
3435 jint result = 0;
3436
3437 if (is_linked()) {
3438 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3439 }
3440
3441 if (is_initialized()) {
3442 assert(is_linked(), "Class status is not consistent");
3443 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3444 }
3445 if (is_in_error_state()) {
3446 result |= JVMTI_CLASS_STATUS_ERROR;
3447 }
3448 return result;
3449 }
3450
3451 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3452 bool implements_interface; // initialized by method_at_itable_or_null
3453 Method* m = method_at_itable_or_null(holder, index,
3454 implements_interface); // out parameter
3455 if (m != nullptr) {
3456 assert(implements_interface, "sanity");
3457 return m;
3458 } else if (implements_interface) {
3459 // Throw AbstractMethodError since corresponding itable slot is empty.
3460 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3461 } else {
3462 // If the interface isn't implemented by the receiver class,
3463 // the VM should throw IncompatibleClassChangeError.
3464 ResourceMark rm(THREAD);
3465 stringStream ss;
3466 bool same_module = (module() == holder->module());
3467 ss.print("Receiver class %s does not implement "
3468 "the interface %s defining the method to be called "
3469 "(%s%s%s)",
3470 external_name(), holder->external_name(),
3471 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3472 (same_module) ? "" : "; ",
3473 (same_module) ? "" : holder->class_in_module_of_loader());
3474 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3475 }
3476 }
3477
3478 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3479 klassItable itable(this);
3480 for (int i = 0; i < itable.size_offset_table(); i++) {
3481 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3482 if (offset_entry->interface_klass() == holder) {
3483 implements_interface = true;
3484 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3485 Method* m = ime[index].method();
3486 return m;
3487 }
3488 }
3489 implements_interface = false;
3490 return nullptr; // offset entry not found
3491 }
3492
3493 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3494 assert(is_linked(), "required");
3495 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3496 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3497
3498 int vtable_index = Method::invalid_vtable_index;
3499 Symbol* name = intf_method->name();
3500 Symbol* signature = intf_method->signature();
3501
3502 // First check in default method array
3503 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3504 int index = find_method_index(default_methods(),
3505 name, signature,
3506 Klass::OverpassLookupMode::find,
3507 Klass::StaticLookupMode::find,
3508 Klass::PrivateLookupMode::find);
3509 if (index >= 0) {
3510 vtable_index = default_vtable_indices()->at(index);
3511 }
3512 }
3513 if (vtable_index == Method::invalid_vtable_index) {
3514 // get vtable_index for miranda methods
3515 klassVtable vt = vtable();
3516 vtable_index = vt.index_of_miranda(name, signature);
3517 }
3518 return vtable_index;
3519 }
3520
3521 #if INCLUDE_JVMTI
3522 // update default_methods for redefineclasses for methods that are
3523 // not yet in the vtable due to concurrent subclass define and superinterface
3524 // redefinition
3525 // Note: those in the vtable, should have been updated via adjust_method_entries
3526 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3527 // search the default_methods for uses of either obsolete or EMCP methods
3528 if (default_methods() != nullptr) {
3529 for (int index = 0; index < default_methods()->length(); index ++) {
3530 Method* old_method = default_methods()->at(index);
3531 if (old_method == nullptr || !old_method->is_old()) {
3532 continue; // skip uninteresting entries
3533 }
3534 assert(!old_method->is_deleted(), "default methods may not be deleted");
3535 Method* new_method = old_method->get_new_method();
3536 default_methods()->at_put(index, new_method);
3537
3538 if (log_is_enabled(Info, redefine, class, update)) {
3539 ResourceMark rm;
3540 if (!(*trace_name_printed)) {
3541 log_info(redefine, class, update)
3542 ("adjust: klassname=%s default methods from name=%s",
3543 external_name(), old_method->method_holder()->external_name());
3544 *trace_name_printed = true;
3545 }
3546 log_debug(redefine, class, update, vtables)
3547 ("default method update: %s(%s) ",
3548 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3549 }
3550 }
3551 }
3552 }
3553 #endif // INCLUDE_JVMTI
3554
3555 // On-stack replacement stuff
3556 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3557 assert_lock_strong(NMethodState_lock);
3558 #ifndef PRODUCT
3559 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3560 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3561 "redundant OSR recompilation detected. memory leak in CodeCache!");
3562 #endif
3563 // only one compilation can be active
3564 assert(n->is_osr_method(), "wrong kind of nmethod");
3565 n->set_osr_link(osr_nmethods_head());
3566 set_osr_nmethods_head(n);
3567 // Raise the highest osr level if necessary
3568 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3569
3570 // Get rid of the osr methods for the same bci that have lower levels.
3571 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3572 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3573 if (inv != nullptr && inv->is_in_use()) {
3574 inv->make_not_entrant("OSR invalidation of lower levels");
3575 }
3576 }
3577 }
3578
3579 // Remove osr nmethod from the list. Return true if found and removed.
3580 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3581 // This is a short non-blocking critical region, so the no safepoint check is ok.
3582 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3583 assert(n->is_osr_method(), "wrong kind of nmethod");
3584 nmethod* last = nullptr;
3585 nmethod* cur = osr_nmethods_head();
3586 int max_level = CompLevel_none; // Find the max comp level excluding n
3587 Method* m = n->method();
3588 // Search for match
3589 bool found = false;
3590 while(cur != nullptr && cur != n) {
3591 if (m == cur->method()) {
3592 // Find max level before n
3593 max_level = MAX2(max_level, cur->comp_level());
3594 }
3595 last = cur;
3596 cur = cur->osr_link();
3597 }
3598 nmethod* next = nullptr;
3599 if (cur == n) {
3600 found = true;
3601 next = cur->osr_link();
3602 if (last == nullptr) {
3603 // Remove first element
3604 set_osr_nmethods_head(next);
3605 } else {
3606 last->set_osr_link(next);
3607 }
3608 }
3609 n->set_osr_link(nullptr);
3610 cur = next;
3611 while (cur != nullptr) {
3612 // Find max level after n
3613 if (m == cur->method()) {
3614 max_level = MAX2(max_level, cur->comp_level());
3615 }
3616 cur = cur->osr_link();
3617 }
3618 m->set_highest_osr_comp_level(max_level);
3619 return found;
3620 }
3621
3622 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3623 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3624 nmethod* osr = osr_nmethods_head();
3625 int found = 0;
3626 while (osr != nullptr) {
3627 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3628 if (osr->method() == m) {
3629 deopt_scope->mark(osr);
3630 found++;
3631 }
3632 osr = osr->osr_link();
3633 }
3634 return found;
3635 }
3636
3637 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3638 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3639 nmethod* osr = osr_nmethods_head();
3640 nmethod* best = nullptr;
3641 while (osr != nullptr) {
3642 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3643 // There can be a time when a c1 osr method exists but we are waiting
3644 // for a c2 version. When c2 completes its osr nmethod we will trash
3645 // the c1 version and only be able to find the c2 version. However
3646 // while we overflow in the c1 code at back branches we don't want to
3647 // try and switch to the same code as we are already running
3648
3649 if (osr->method() == m &&
3650 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3651 if (match_level) {
3652 if (osr->comp_level() == comp_level) {
3653 // Found a match - return it.
3654 return osr;
3655 }
3656 } else {
3657 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3658 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3659 // Found the best possible - return it.
3660 return osr;
3661 }
3662 best = osr;
3663 }
3664 }
3665 }
3666 osr = osr->osr_link();
3667 }
3668
3669 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3670 if (best != nullptr && best->comp_level() >= comp_level) {
3671 return best;
3672 }
3673 return nullptr;
3674 }
3675
3676 // -----------------------------------------------------------------------------------------------------
3677 // Printing
3678
3679 #define BULLET " - "
3680
3681 static const char* state_names[] = {
3682 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3683 };
3684
3685 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3686 for (int i = 0; i < len; i++) {
3687 intptr_t e = start[i];
3688 st->print("%d : " INTPTR_FORMAT, i, e);
3689 if (MetaspaceObj::is_valid((Metadata*)e)) {
3690 st->print(" ");
3691 ((Metadata*)e)->print_value_on(st);
3692 }
3693 st->cr();
3694 }
3695 }
3696
3697 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3698 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3699 }
3700
3701 const char* InstanceKlass::init_state_name() const {
3702 return state_names[init_state()];
3703 }
3704
3705 const char* InstanceKlass::state2name(ClassState s) {
3706 return state_names[s];
3707 }
3708
3709 void InstanceKlass::print_on(outputStream* st) const {
3710 assert(is_klass(), "must be klass");
3711 Klass::print_on(st);
3712
3713 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3714 st->print(BULLET"klass size: %d", size()); st->cr();
3715 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3716 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3717 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3718 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3719 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3720 st->print(BULLET"sub: ");
3721 Klass* sub = subklass();
3722 int n;
3723 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3724 if (n < MaxSubklassPrintSize) {
3725 sub->print_value_on(st);
3726 st->print(" ");
3727 }
3728 }
3729 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3730 st->cr();
3731
3732 if (is_interface()) {
3733 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3734 if (nof_implementors() == 1) {
3735 st->print_cr(BULLET"implementor: ");
3736 st->print(" ");
3737 implementor()->print_value_on(st);
3738 st->cr();
3739 }
3740 }
3741
3742 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3743 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3744 if (Verbose || WizardMode) {
3745 Array<Method*>* method_array = methods();
3746 for (int i = 0; i < method_array->length(); i++) {
3747 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3748 }
3749 }
3750 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3751 if (default_methods() != nullptr) {
3752 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3753 if (Verbose) {
3754 Array<Method*>* method_array = default_methods();
3755 for (int i = 0; i < method_array->length(); i++) {
3756 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3757 }
3758 }
3759 }
3760 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3761 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3762 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3763
3764 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3765
3766 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3767 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3768
3769 if (secondary_supers() != nullptr) {
3770 if (Verbose) {
3771 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3772 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3773 for (int i = 0; i < _secondary_supers->length(); i++) {
3774 ResourceMark rm; // for external_name()
3775 Klass* secondary_super = _secondary_supers->at(i);
3776 st->print(BULLET"%2d:", i);
3777 if (is_hashed) {
3778 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3779 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3780 st->print(" dist:%02d:", distance);
3781 }
3782 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3783 }
3784 }
3785 }
3786 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3787
3788 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3789 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3790 if (source_debug_extension() != nullptr) {
3791 st->print(BULLET"source debug extension: ");
3792 st->print("%s", source_debug_extension());
3793 st->cr();
3794 }
3795 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3796 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3797 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3798 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3799 {
3800 bool have_pv = false;
3801 // previous versions are linked together through the InstanceKlass
3802 for (InstanceKlass* pv_node = previous_versions();
3803 pv_node != nullptr;
3804 pv_node = pv_node->previous_versions()) {
3805 if (!have_pv)
3806 st->print(BULLET"previous version: ");
3807 have_pv = true;
3808 pv_node->constants()->print_value_on(st);
3809 }
3810 if (have_pv) st->cr();
3811 }
3812
3813 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3814 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3815 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3816 print_on_maybe_null(st, BULLET"record components: ", record_components());
3817 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3818 if (java_mirror() != nullptr) {
3819 st->print(BULLET"java mirror: ");
3820 java_mirror()->print_value_on(st);
3821 st->cr();
3822 } else {
3823 st->print_cr(BULLET"java mirror: null");
3824 }
3825 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3826 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3827 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3828 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3829 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3830
3831 FieldPrinter print_static_field(st);
3832 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3833 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3834 FieldPrinter print_nonstatic_field(st);
3835 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3836 ik->print_nonstatic_fields(&print_nonstatic_field);
3837
3838 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3839 OopMapBlock* map = start_of_nonstatic_oop_maps();
3840 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3841 while (map < end_map) {
3842 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3843 map++;
3844 }
3845 st->cr();
3846 }
3847
3848 void InstanceKlass::print_value_on(outputStream* st) const {
3849 assert(is_klass(), "must be klass");
3850 if (Verbose || WizardMode) access_flags().print_on(st);
3851 name()->print_value_on(st);
3852 }
3853
3854 void FieldPrinter::do_field(fieldDescriptor* fd) {
3855 _st->print(BULLET);
3856 if (_obj == nullptr) {
3857 fd->print_on(_st);
3858 _st->cr();
3859 } else {
3860 fd->print_on_for(_st, _obj);
3861 _st->cr();
3862 }
3863 }
3864
3865
3866 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3867 Klass::oop_print_on(obj, st);
3868
3869 if (this == vmClasses::String_klass()) {
3870 typeArrayOop value = java_lang_String::value(obj);
3871 juint length = java_lang_String::length(obj);
3872 if (value != nullptr &&
3873 value->is_typeArray() &&
3874 length <= (juint) value->length()) {
3875 st->print(BULLET"string: ");
3876 java_lang_String::print(obj, st);
3877 st->cr();
3878 }
3879 }
3880
3881 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3882 FieldPrinter print_field(st, obj);
3883 print_nonstatic_fields(&print_field);
3884
3885 if (this == vmClasses::Class_klass()) {
3886 st->print(BULLET"signature: ");
3887 java_lang_Class::print_signature(obj, st);
3888 st->cr();
3889 Klass* real_klass = java_lang_Class::as_Klass(obj);
3890 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3891 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3892 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3893 }
3894 } else if (this == vmClasses::MethodType_klass()) {
3895 st->print(BULLET"signature: ");
3896 java_lang_invoke_MethodType::print_signature(obj, st);
3897 st->cr();
3898 }
3899 }
3900
3901 #ifndef PRODUCT
3902
3903 bool InstanceKlass::verify_itable_index(int i) {
3904 int method_count = klassItable::method_count_for_interface(this);
3905 assert(i >= 0 && i < method_count, "index out of bounds");
3906 return true;
3907 }
3908
3909 #endif //PRODUCT
3910
3911 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3912 st->print("a ");
3913 name()->print_value_on(st);
3914 obj->print_address_on(st);
3915 if (this == vmClasses::String_klass()
3916 && java_lang_String::value(obj) != nullptr) {
3917 ResourceMark rm;
3918 int len = java_lang_String::length(obj);
3919 int plen = (len < 24 ? len : 12);
3920 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3921 st->print(" = \"%s\"", str);
3922 if (len > plen)
3923 st->print("...[%d]", len);
3924 } else if (this == vmClasses::Class_klass()) {
3925 Klass* k = java_lang_Class::as_Klass(obj);
3926 st->print(" = ");
3927 if (k != nullptr) {
3928 k->print_value_on(st);
3929 } else {
3930 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3931 st->print("%s", tname ? tname : "type?");
3932 }
3933 } else if (this == vmClasses::MethodType_klass()) {
3934 st->print(" = ");
3935 java_lang_invoke_MethodType::print_signature(obj, st);
3936 } else if (java_lang_boxing_object::is_instance(obj)) {
3937 st->print(" = ");
3938 java_lang_boxing_object::print(obj, st);
3939 } else if (this == vmClasses::LambdaForm_klass()) {
3940 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3941 if (vmentry != nullptr) {
3942 st->print(" => ");
3943 vmentry->print_value_on(st);
3944 }
3945 } else if (this == vmClasses::MemberName_klass()) {
3946 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3947 if (vmtarget != nullptr) {
3948 st->print(" = ");
3949 vmtarget->print_value_on(st);
3950 } else {
3951 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3952 oop name = java_lang_invoke_MemberName::name(obj);
3953 if (clazz != nullptr) {
3954 clazz->print_value_on(st);
3955 } else {
3956 st->print("null");
3957 }
3958 st->print(".");
3959 if (name != nullptr) {
3960 name->print_value_on(st);
3961 } else {
3962 st->print("null");
3963 }
3964 }
3965 }
3966 }
3967
3968 const char* InstanceKlass::internal_name() const {
3969 return external_name();
3970 }
3971
3972 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3973 const ModuleEntry* module_entry,
3974 const ClassFileStream* cfs) const {
3975
3976 if (ClassListWriter::is_enabled()) {
3977 ClassListWriter::write(this, cfs);
3978 }
3979
3980 print_class_load_helper(loader_data, module_entry, cfs);
3981 print_class_load_cause_logging();
3982 }
3983
3984 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3985 const ModuleEntry* module_entry,
3986 const ClassFileStream* cfs) const {
3987
3988 if (!log_is_enabled(Info, class, load)) {
3989 return;
3990 }
3991
3992 ResourceMark rm;
3993 LogMessage(class, load) msg;
3994 stringStream info_stream;
3995
3996 // Name and class hierarchy info
3997 info_stream.print("%s", external_name());
3998
3999 // Source
4000 if (cfs != nullptr) {
4001 if (cfs->source() != nullptr) {
4002 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4003 if (module_name != nullptr) {
4004 // When the boot loader created the stream, it didn't know the module name
4005 // yet. Let's format it now.
4006 if (cfs->from_boot_loader_modules_image()) {
4007 info_stream.print(" source: jrt:/%s", module_name);
4008 } else {
4009 info_stream.print(" source: %s", cfs->source());
4010 }
4011 } else {
4012 info_stream.print(" source: %s", cfs->source());
4013 }
4014 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4015 Thread* current = Thread::current();
4016 Klass* caller = current->is_Java_thread() ?
4017 JavaThread::cast(current)->security_get_caller_class(1):
4018 nullptr;
4019 // caller can be null, for example, during a JVMTI VM_Init hook
4020 if (caller != nullptr) {
4021 info_stream.print(" source: instance of %s", caller->external_name());
4022 } else {
4023 // source is unknown
4024 }
4025 } else {
4026 oop class_loader = loader_data->class_loader();
4027 info_stream.print(" source: %s", class_loader->klass()->external_name());
4028 }
4029 } else {
4030 assert(this->is_shared(), "must be");
4031 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4032 info_stream.print(" source: shared objects file (top)");
4033 } else {
4034 info_stream.print(" source: shared objects file");
4035 }
4036 }
4037
4038 info_stream.print(" loader:");
4039 if (is_shared()) {
4040 info_stream.print(" %s", SystemDictionaryShared::loader_type_for_shared_class((Klass*)this));
4041 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4042 info_stream.print(" boot_loader");
4043 } else {
4044 oop class_loader = loader_data->class_loader();
4045 if (class_loader != nullptr) {
4046 info_stream.print(" %s", class_loader->klass()->external_name());
4047 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4048 if (cl_name_and_id != nullptr) {
4049 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4050 }
4051 } else {
4052 info_stream.print(" null");
4053 }
4054 }
4055 msg.info("%s", info_stream.as_string());
4056
4057 if (log_is_enabled(Debug, class, load)) {
4058 stringStream debug_stream;
4059
4060 // Class hierarchy info
4061 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4062 p2i(this), p2i(superklass()));
4063
4064 // Interfaces
4065 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4066 debug_stream.print(" interfaces:");
4067 int length = local_interfaces()->length();
4068 for (int i = 0; i < length; i++) {
4069 debug_stream.print(" " PTR_FORMAT,
4070 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4071 }
4072 }
4073
4074 // Class loader
4075 debug_stream.print(" loader: [");
4076 loader_data->print_value_on(&debug_stream);
4077 debug_stream.print("]");
4078
4079 // Classfile checksum
4080 if (cfs) {
4081 debug_stream.print(" bytes: %d checksum: %08x",
4082 cfs->length(),
4083 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4084 cfs->length()));
4085 }
4086
4087 msg.debug("%s", debug_stream.as_string());
4088 }
4089 }
4090
4091 void InstanceKlass::print_class_load_cause_logging() const {
4092 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4093 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4094 JavaThread* current = JavaThread::current();
4095 ResourceMark rm(current);
4096 const char* name = external_name();
4097
4098 if (LogClassLoadingCauseFor == nullptr ||
4099 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4100 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4101 return;
4102 }
4103
4104 // Log Java stack first
4105 {
4106 LogMessage(class, load, cause) msg;
4107 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4108
4109 info_stream.print_cr("Java stack when loading %s:", name);
4110 current->print_stack_on(&info_stream);
4111 }
4112
4113 // Log native stack second
4114 if (log_cause_native) {
4115 // Log to string first so that lines can be indented
4116 stringStream stack_stream;
4117 char buf[O_BUFLEN];
4118 address lastpc = nullptr;
4119 NativeStackPrinter nsp(current);
4120 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4121 true /* print_source_info */, -1 /* max stack */);
4122
4123 LogMessage(class, load, cause, native) msg;
4124 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4125 info_stream.print_cr("Native stack when loading %s:", name);
4126
4127 // Print each native stack line to the log
4128 int size = (int) stack_stream.size();
4129 char* stack = stack_stream.as_string();
4130 char* stack_end = stack + size;
4131 char* line_start = stack;
4132 for (char* p = stack; p < stack_end; p++) {
4133 if (*p == '\n') {
4134 *p = '\0';
4135 info_stream.print_cr("\t%s", line_start);
4136 line_start = p + 1;
4137 }
4138 }
4139 if (line_start < stack_end) {
4140 info_stream.print_cr("\t%s", line_start);
4141 }
4142 }
4143 }
4144 }
4145
4146 // Verification
4147
4148 class VerifyFieldClosure: public BasicOopIterateClosure {
4149 protected:
4150 template <class T> void do_oop_work(T* p) {
4151 oop obj = RawAccess<>::oop_load(p);
4152 if (!oopDesc::is_oop_or_null(obj)) {
4153 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4154 Universe::print_on(tty);
4155 guarantee(false, "boom");
4156 }
4157 }
4158 public:
4159 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4160 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4161 };
4162
4163 void InstanceKlass::verify_on(outputStream* st) {
4164 #ifndef PRODUCT
4165 // Avoid redundant verifies, this really should be in product.
4166 if (_verify_count == Universe::verify_count()) return;
4167 _verify_count = Universe::verify_count();
4168 #endif
4169
4170 // Verify Klass
4171 Klass::verify_on(st);
4172
4173 // Verify that klass is present in ClassLoaderData
4174 guarantee(class_loader_data()->contains_klass(this),
4175 "this class isn't found in class loader data");
4176
4177 // Verify vtables
4178 if (is_linked()) {
4179 // $$$ This used to be done only for m/s collections. Doing it
4180 // always seemed a valid generalization. (DLD -- 6/00)
4181 vtable().verify(st);
4182 }
4183
4184 // Verify first subklass
4185 if (subklass() != nullptr) {
4186 guarantee(subklass()->is_klass(), "should be klass");
4187 }
4188
4189 // Verify siblings
4190 Klass* super = this->super();
4191 Klass* sib = next_sibling();
4192 if (sib != nullptr) {
4193 if (sib == this) {
4194 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4195 }
4196
4197 guarantee(sib->is_klass(), "should be klass");
4198 guarantee(sib->super() == super, "siblings should have same superklass");
4199 }
4200
4201 // Verify local interfaces
4202 if (local_interfaces()) {
4203 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4204 for (int j = 0; j < local_interfaces->length(); j++) {
4205 InstanceKlass* e = local_interfaces->at(j);
4206 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4207 }
4208 }
4209
4210 // Verify transitive interfaces
4211 if (transitive_interfaces() != nullptr) {
4212 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4213 for (int j = 0; j < transitive_interfaces->length(); j++) {
4214 InstanceKlass* e = transitive_interfaces->at(j);
4215 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4216 }
4217 }
4218
4219 // Verify methods
4220 if (methods() != nullptr) {
4221 Array<Method*>* methods = this->methods();
4222 for (int j = 0; j < methods->length(); j++) {
4223 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4224 }
4225 for (int j = 0; j < methods->length() - 1; j++) {
4226 Method* m1 = methods->at(j);
4227 Method* m2 = methods->at(j + 1);
4228 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4229 }
4230 }
4231
4232 // Verify method ordering
4233 if (method_ordering() != nullptr) {
4234 Array<int>* method_ordering = this->method_ordering();
4235 int length = method_ordering->length();
4236 if (JvmtiExport::can_maintain_original_method_order() ||
4237 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4238 guarantee(length == methods()->length(), "invalid method ordering length");
4239 jlong sum = 0;
4240 for (int j = 0; j < length; j++) {
4241 int original_index = method_ordering->at(j);
4242 guarantee(original_index >= 0, "invalid method ordering index");
4243 guarantee(original_index < length, "invalid method ordering index");
4244 sum += original_index;
4245 }
4246 // Verify sum of indices 0,1,...,length-1
4247 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4248 } else {
4249 guarantee(length == 0, "invalid method ordering length");
4250 }
4251 }
4252
4253 // Verify default methods
4254 if (default_methods() != nullptr) {
4255 Array<Method*>* methods = this->default_methods();
4256 for (int j = 0; j < methods->length(); j++) {
4257 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4258 }
4259 for (int j = 0; j < methods->length() - 1; j++) {
4260 Method* m1 = methods->at(j);
4261 Method* m2 = methods->at(j + 1);
4262 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4263 }
4264 }
4265
4266 // Verify JNI static field identifiers
4267 if (jni_ids() != nullptr) {
4268 jni_ids()->verify(this);
4269 }
4270
4271 // Verify other fields
4272 if (constants() != nullptr) {
4273 guarantee(constants()->is_constantPool(), "should be constant pool");
4274 }
4275 }
4276
4277 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4278 Klass::oop_verify_on(obj, st);
4279 VerifyFieldClosure blk;
4280 obj->oop_iterate(&blk);
4281 }
4282
4283
4284 // JNIid class for jfieldIDs only
4285 // Note to reviewers:
4286 // These JNI functions are just moved over to column 1 and not changed
4287 // in the compressed oops workspace.
4288 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4289 _holder = holder;
4290 _offset = offset;
4291 _next = next;
4292 DEBUG_ONLY(_is_static_field_id = false;)
4293 }
4294
4295
4296 JNIid* JNIid::find(int offset) {
4297 JNIid* current = this;
4298 while (current != nullptr) {
4299 if (current->offset() == offset) return current;
4300 current = current->next();
4301 }
4302 return nullptr;
4303 }
4304
4305 void JNIid::deallocate(JNIid* current) {
4306 while (current != nullptr) {
4307 JNIid* next = current->next();
4308 delete current;
4309 current = next;
4310 }
4311 }
4312
4313
4314 void JNIid::verify(Klass* holder) {
4315 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4316 int end_field_offset;
4317 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4318
4319 JNIid* current = this;
4320 while (current != nullptr) {
4321 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4322 #ifdef ASSERT
4323 int o = current->offset();
4324 if (current->is_static_field_id()) {
4325 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4326 }
4327 #endif
4328 current = current->next();
4329 }
4330 }
4331
4332 void InstanceKlass::set_init_state(ClassState state) {
4333 #ifdef ASSERT
4334 bool good_state = is_shared() ? (_init_state <= state)
4335 : (_init_state < state);
4336 assert(good_state || state == allocated, "illegal state transition");
4337 #endif
4338 assert(_init_thread == nullptr, "should be cleared before state change");
4339 Atomic::release_store(&_init_state, state);
4340 }
4341
4342 #if INCLUDE_JVMTI
4343
4344 // RedefineClasses() support for previous versions
4345
4346 // Globally, there is at least one previous version of a class to walk
4347 // during class unloading, which is saved because old methods in the class
4348 // are still running. Otherwise the previous version list is cleaned up.
4349 bool InstanceKlass::_should_clean_previous_versions = false;
4350
4351 // Returns true if there are previous versions of a class for class
4352 // unloading only. Also resets the flag to false. purge_previous_version
4353 // will set the flag to true if there are any left, i.e., if there's any
4354 // work to do for next time. This is to avoid the expensive code cache
4355 // walk in CLDG::clean_deallocate_lists().
4356 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4357 bool ret = _should_clean_previous_versions;
4358 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4359 ret ? "true" : "false");
4360 _should_clean_previous_versions = false;
4361 return ret;
4362 }
4363
4364 // This nulls out jmethodIDs for all methods in 'klass'
4365 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4366 // during class unloading.
4367 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4368 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4369 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4370 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4371 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4372 Array<Method*>* method_refs = klass->methods();
4373 for (int k = 0; k < method_refs->length(); k++) {
4374 Method* method = method_refs->at(k);
4375 if (method != nullptr && method->is_obsolete()) {
4376 method->clear_jmethod_id();
4377 }
4378 }
4379 }
4380
4381 // Purge previous versions before adding new previous versions of the class and
4382 // during class unloading.
4383 void InstanceKlass::purge_previous_version_list() {
4384 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4385 assert(has_been_redefined(), "Should only be called for main class");
4386
4387 // Quick exit.
4388 if (previous_versions() == nullptr) {
4389 return;
4390 }
4391
4392 // This klass has previous versions so see what we can cleanup
4393 // while it is safe to do so.
4394
4395 int deleted_count = 0; // leave debugging breadcrumbs
4396 int live_count = 0;
4397 ClassLoaderData* loader_data = class_loader_data();
4398 assert(loader_data != nullptr, "should never be null");
4399
4400 ResourceMark rm;
4401 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4402
4403 // previous versions are linked together through the InstanceKlass
4404 InstanceKlass* pv_node = previous_versions();
4405 InstanceKlass* last = this;
4406 int version = 0;
4407
4408 // check the previous versions list
4409 for (; pv_node != nullptr; ) {
4410
4411 ConstantPool* pvcp = pv_node->constants();
4412 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4413
4414 if (!pvcp->on_stack()) {
4415 // If the constant pool isn't on stack, none of the methods
4416 // are executing. Unlink this previous_version.
4417 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4418 // so will be deallocated during the next phase of class unloading.
4419 log_trace(redefine, class, iklass, purge)
4420 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4421 // Unlink from previous version list.
4422 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4423 InstanceKlass* next = pv_node->previous_versions();
4424 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4425 pv_node->link_previous_versions(nullptr); // point next to null
4426 last->link_previous_versions(next);
4427 // Delete this node directly. Nothing is referring to it and we don't
4428 // want it to increase the counter for metadata to delete in CLDG.
4429 MetadataFactory::free_metadata(loader_data, pv_node);
4430 pv_node = next;
4431 deleted_count++;
4432 version++;
4433 continue;
4434 } else {
4435 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4436 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4437 live_count++;
4438 if (pvcp->is_shared()) {
4439 // Shared previous versions can never be removed so no cleaning is needed.
4440 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4441 } else {
4442 // Previous version alive, set that clean is needed for next time.
4443 _should_clean_previous_versions = true;
4444 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4445 }
4446 }
4447
4448 // next previous version
4449 last = pv_node;
4450 pv_node = pv_node->previous_versions();
4451 version++;
4452 }
4453 log_trace(redefine, class, iklass, purge)
4454 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4455 }
4456
4457 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4458 int emcp_method_count) {
4459 int obsolete_method_count = old_methods->length() - emcp_method_count;
4460
4461 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4462 _previous_versions != nullptr) {
4463 // We have a mix of obsolete and EMCP methods so we have to
4464 // clear out any matching EMCP method entries the hard way.
4465 int local_count = 0;
4466 for (int i = 0; i < old_methods->length(); i++) {
4467 Method* old_method = old_methods->at(i);
4468 if (old_method->is_obsolete()) {
4469 // only obsolete methods are interesting
4470 Symbol* m_name = old_method->name();
4471 Symbol* m_signature = old_method->signature();
4472
4473 // previous versions are linked together through the InstanceKlass
4474 int j = 0;
4475 for (InstanceKlass* prev_version = _previous_versions;
4476 prev_version != nullptr;
4477 prev_version = prev_version->previous_versions(), j++) {
4478
4479 Array<Method*>* method_refs = prev_version->methods();
4480 for (int k = 0; k < method_refs->length(); k++) {
4481 Method* method = method_refs->at(k);
4482
4483 if (!method->is_obsolete() &&
4484 method->name() == m_name &&
4485 method->signature() == m_signature) {
4486 // The current RedefineClasses() call has made all EMCP
4487 // versions of this method obsolete so mark it as obsolete
4488 log_trace(redefine, class, iklass, add)
4489 ("%s(%s): flush obsolete method @%d in version @%d",
4490 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4491
4492 method->set_is_obsolete();
4493 break;
4494 }
4495 }
4496
4497 // The previous loop may not find a matching EMCP method, but
4498 // that doesn't mean that we can optimize and not go any
4499 // further back in the PreviousVersion generations. The EMCP
4500 // method for this generation could have already been made obsolete,
4501 // but there still may be an older EMCP method that has not
4502 // been made obsolete.
4503 }
4504
4505 if (++local_count >= obsolete_method_count) {
4506 // no more obsolete methods so bail out now
4507 break;
4508 }
4509 }
4510 }
4511 }
4512 }
4513
4514 // Save the scratch_class as the previous version if any of the methods are running.
4515 // The previous_versions are used to set breakpoints in EMCP methods and they are
4516 // also used to clean MethodData links to redefined methods that are no longer running.
4517 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4518 int emcp_method_count) {
4519 assert(Thread::current()->is_VM_thread(),
4520 "only VMThread can add previous versions");
4521
4522 ResourceMark rm;
4523 log_trace(redefine, class, iklass, add)
4524 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4525
4526 // Clean out old previous versions for this class
4527 purge_previous_version_list();
4528
4529 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4530 // a previous redefinition may be made obsolete by this redefinition.
4531 Array<Method*>* old_methods = scratch_class->methods();
4532 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4533
4534 // If the constant pool for this previous version of the class
4535 // is not marked as being on the stack, then none of the methods
4536 // in this previous version of the class are on the stack so
4537 // we don't need to add this as a previous version.
4538 ConstantPool* cp_ref = scratch_class->constants();
4539 if (!cp_ref->on_stack()) {
4540 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4541 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4542 return;
4543 }
4544
4545 // Add previous version if any methods are still running or if this is
4546 // a shared class which should never be removed.
4547 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4548 scratch_class->link_previous_versions(previous_versions());
4549 link_previous_versions(scratch_class);
4550 if (cp_ref->is_shared()) {
4551 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4552 } else {
4553 // We only set clean_previous_versions flag for processing during class
4554 // unloading for non-shared classes.
4555 _should_clean_previous_versions = true;
4556 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4557 }
4558 } // end add_previous_version()
4559
4560 #endif // INCLUDE_JVMTI
4561
4562 Method* InstanceKlass::method_with_idnum(int idnum) const {
4563 Method* m = nullptr;
4564 if (idnum < methods()->length()) {
4565 m = methods()->at(idnum);
4566 }
4567 if (m == nullptr || m->method_idnum() != idnum) {
4568 for (int index = 0; index < methods()->length(); ++index) {
4569 m = methods()->at(index);
4570 if (m->method_idnum() == idnum) {
4571 return m;
4572 }
4573 }
4574 // None found, return null for the caller to handle.
4575 return nullptr;
4576 }
4577 return m;
4578 }
4579
4580
4581 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4582 if (idnum >= methods()->length()) {
4583 return nullptr;
4584 }
4585 Method* m = methods()->at(idnum);
4586 if (m != nullptr && m->orig_method_idnum() == idnum) {
4587 return m;
4588 }
4589 // Obsolete method idnum does not match the original idnum
4590 for (int index = 0; index < methods()->length(); ++index) {
4591 m = methods()->at(index);
4592 if (m->orig_method_idnum() == idnum) {
4593 return m;
4594 }
4595 }
4596 // None found, return null for the caller to handle.
4597 return nullptr;
4598 }
4599
4600
4601 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4602 const InstanceKlass* holder = get_klass_version(version);
4603 if (holder == nullptr) {
4604 return nullptr; // The version of klass is gone, no method is found
4605 }
4606 return holder->method_with_orig_idnum(idnum);
4607 }
4608
4609 #if INCLUDE_JVMTI
4610 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4611 return _cached_class_file;
4612 }
4613
4614 jint InstanceKlass::get_cached_class_file_len() {
4615 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4616 }
4617
4618 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4619 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4620 }
4621 #endif
4622
4623 // Make a step iterating over the class hierarchy under the root class.
4624 // Skips subclasses if requested.
4625 void ClassHierarchyIterator::next() {
4626 assert(_current != nullptr, "required");
4627 if (_visit_subclasses && _current->subklass() != nullptr) {
4628 _current = _current->subklass();
4629 return; // visit next subclass
4630 }
4631 _visit_subclasses = true; // reset
4632 while (_current->next_sibling() == nullptr && _current != _root) {
4633 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4634 }
4635 if (_current == _root) {
4636 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4637 _current = nullptr;
4638 return;
4639 }
4640 _current = _current->next_sibling();
4641 return; // visit next sibling subclass
4642 }