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 (log_is_enabled(Info, cds, init)) {
866 ResourceMark rm;
867 log_info(cds, init)("%s (aot-inited)", external_name());
868 }
869
870 link_class(CHECK);
871
872 #ifdef ASSERT
873 {
874 Handle h_init_lock(THREAD, init_lock());
875 ObjectLocker ol(h_init_lock, THREAD);
876 assert(!is_initialized(), "sanity");
877 assert(!is_being_initialized(), "sanity");
878 assert(!is_in_error_state(), "sanity");
879 }
880 #endif
881
882 set_init_thread(THREAD);
883 set_initialization_state_and_notify(fully_initialized, CHECK);
884 AOTClassInitializer::call_runtime_setup(THREAD, this);
885 }
886 #endif
887
888 bool InstanceKlass::verify_code(TRAPS) {
889 // 1) Verify the bytecodes
890 return Verifier::verify(this, should_verify_class(), THREAD);
891 }
892
893 void InstanceKlass::link_class(TRAPS) {
894 assert(is_loaded(), "must be loaded");
895 if (!is_linked()) {
896 link_class_impl(CHECK);
897 }
898 }
899
900 // Called to verify that a class can link during initialization, without
901 // throwing a VerifyError.
902 bool InstanceKlass::link_class_or_fail(TRAPS) {
903 assert(is_loaded(), "must be loaded");
904 if (!is_linked()) {
905 link_class_impl(CHECK_false);
906 }
907 return is_linked();
908 }
909
910 bool InstanceKlass::link_class_impl(TRAPS) {
911 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
912 // This is for CDS static dump only -- we use the in_error_state to indicate that
913 // the class has failed verification. Throwing the NoClassDefFoundError here is just
914 // a convenient way to stop repeat attempts to verify the same (bad) class.
915 //
916 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
917 // if we are executing Java code. This is not a problem for CDS dumping phase since
918 // it doesn't execute any Java code.
919 ResourceMark rm(THREAD);
920 // Names are all known to be < 64k so we know this formatted message is not excessively large.
921 Exceptions::fthrow(THREAD_AND_LOCATION,
922 vmSymbols::java_lang_NoClassDefFoundError(),
923 "Class %s, or one of its supertypes, failed class initialization",
924 external_name());
925 return false;
926 }
927 // return if already verified
928 if (is_linked()) {
929 return true;
930 }
931
932 // Timing
933 // timer handles recursion
934 JavaThread* jt = THREAD;
935
936 // link super class before linking this class
937 Klass* super_klass = super();
938 if (super_klass != nullptr) {
939 if (super_klass->is_interface()) { // check if super class is an interface
940 ResourceMark rm(THREAD);
941 // Names are all known to be < 64k so we know this formatted message is not excessively large.
942 Exceptions::fthrow(
943 THREAD_AND_LOCATION,
944 vmSymbols::java_lang_IncompatibleClassChangeError(),
945 "class %s has interface %s as super class",
946 external_name(),
947 super_klass->external_name()
948 );
949 return false;
950 }
951
952 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
953 ik_super->link_class_impl(CHECK_false);
954 }
955
956 // link all interfaces implemented by this class before linking this class
957 Array<InstanceKlass*>* interfaces = local_interfaces();
958 int num_interfaces = interfaces->length();
959 for (int index = 0; index < num_interfaces; index++) {
960 InstanceKlass* interk = interfaces->at(index);
961 interk->link_class_impl(CHECK_false);
962 }
963
964 // in case the class is linked in the process of linking its superclasses
965 if (is_linked()) {
966 return true;
967 }
968
969 // trace only the link time for this klass that includes
970 // the verification time
971 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
972 ClassLoader::perf_class_link_selftime(),
973 ClassLoader::perf_classes_linked(),
974 jt->get_thread_stat()->perf_recursion_counts_addr(),
975 jt->get_thread_stat()->perf_timers_addr(),
976 PerfClassTraceTime::CLASS_LINK);
977
978 // verification & rewriting
979 {
980 HandleMark hm(THREAD);
981 Handle h_init_lock(THREAD, init_lock());
982 ObjectLocker ol(h_init_lock, jt);
983 // rewritten will have been set if loader constraint error found
984 // on an earlier link attempt
985 // don't verify or rewrite if already rewritten
986 //
987
988 if (!is_linked()) {
989 if (!is_rewritten()) {
990 if (is_shared()) {
991 assert(!verified_at_dump_time(), "must be");
992 }
993 {
994 bool verify_ok = verify_code(THREAD);
995 if (!verify_ok) {
996 return false;
997 }
998 }
999
1000 // Just in case a side-effect of verify linked this class already
1001 // (which can sometimes happen since the verifier loads classes
1002 // using custom class loaders, which are free to initialize things)
1003 if (is_linked()) {
1004 return true;
1005 }
1006
1007 // also sets rewritten
1008 rewrite_class(CHECK_false);
1009 } else if (is_shared()) {
1010 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1011 }
1012
1013 // relocate jsrs and link methods after they are all rewritten
1014 link_methods(CHECK_false);
1015
1016 // Initialize the vtable and interface table after
1017 // methods have been rewritten since rewrite may
1018 // fabricate new Method*s.
1019 // also does loader constraint checking
1020 //
1021 // initialize_vtable and initialize_itable need to be rerun
1022 // for a shared class if
1023 // 1) the class is loaded by custom class loader or
1024 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1025 // 3) the class was not verified during dump time
1026 bool need_init_table = true;
1027 if (is_shared() && verified_at_dump_time() &&
1028 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1029 need_init_table = false;
1030 }
1031 if (need_init_table) {
1032 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1033 itable().initialize_itable_and_check_constraints(CHECK_false);
1034 }
1035 #ifdef ASSERT
1036 vtable().verify(tty, true);
1037 // In case itable verification is ever added.
1038 // itable().verify(tty, true);
1039 #endif
1040 if (Universe::is_fully_initialized()) {
1041 DeoptimizationScope deopt_scope;
1042 {
1043 // Now mark all code that assumes the class is not linked.
1044 // Set state under the Compile_lock also.
1045 MutexLocker ml(THREAD, Compile_lock);
1046
1047 set_init_state(linked);
1048 CodeCache::mark_dependents_on(&deopt_scope, this);
1049 }
1050 // Perform the deopt handshake outside Compile_lock.
1051 deopt_scope.deoptimize_marked();
1052 } else {
1053 set_init_state(linked);
1054 }
1055 if (JvmtiExport::should_post_class_prepare()) {
1056 JvmtiExport::post_class_prepare(THREAD, this);
1057 }
1058 }
1059 }
1060 return true;
1061 }
1062
1063 // Rewrite the byte codes of all of the methods of a class.
1064 // The rewriter must be called exactly once. Rewriting must happen after
1065 // verification but before the first method of the class is executed.
1066 void InstanceKlass::rewrite_class(TRAPS) {
1067 assert(is_loaded(), "must be loaded");
1068 if (is_rewritten()) {
1069 assert(is_shared(), "rewriting an unshared class?");
1070 return;
1071 }
1072 Rewriter::rewrite(this, CHECK);
1073 set_rewritten();
1074 }
1075
1076 // Now relocate and link method entry points after class is rewritten.
1077 // This is outside is_rewritten flag. In case of an exception, it can be
1078 // executed more than once.
1079 void InstanceKlass::link_methods(TRAPS) {
1080 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1081
1082 int len = methods()->length();
1083 for (int i = len-1; i >= 0; i--) {
1084 methodHandle m(THREAD, methods()->at(i));
1085 RuntimeUpcalls::install_upcalls(m);
1086
1087 // Set up method entry points for compiler and interpreter .
1088 m->link_method(m, CHECK);
1089 }
1090 }
1091
1092 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1093 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1094 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1095 for (int i = 0; i < local_interfaces()->length(); ++i) {
1096 InstanceKlass* ik = local_interfaces()->at(i);
1097
1098 // Initialization is depth first search ie. we start with top of the inheritance tree
1099 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1100 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1101 if (ik->has_nonstatic_concrete_methods()) {
1102 ik->initialize_super_interfaces(CHECK);
1103 }
1104
1105 // Only initialize() interfaces that "declare" concrete methods.
1106 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1107 ik->initialize(CHECK);
1108 }
1109 }
1110 }
1111
1112 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1113 static InitializationErrorTable* _initialization_error_table;
1114
1115 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1116 // Create the same exception with a message indicating the thread name,
1117 // and the StackTraceElements.
1118 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1119 ResourceMark rm(current);
1120 if (init_error.is_null()) {
1121 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1122
1123 // We failed to create the new exception, most likely due to either out-of-memory or
1124 // a stackoverflow error. If the original exception was either of those then we save
1125 // the shared, pre-allocated, stackless, instance of that exception.
1126 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1127 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1128 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1129 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1130 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1131 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1132 } else {
1133 return;
1134 }
1135 }
1136
1137 MutexLocker ml(current, ClassInitError_lock);
1138 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1139 bool created;
1140 if (_initialization_error_table == nullptr) {
1141 _initialization_error_table = new (mtClass) InitializationErrorTable();
1142 }
1143 _initialization_error_table->put_if_absent(this, elem, &created);
1144 assert(created, "Initialization is single threaded");
1145 log_trace(class, init)("Initialization error added for class %s", external_name());
1146 }
1147
1148 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1149 MutexLocker ml(current, ClassInitError_lock);
1150 if (_initialization_error_table == nullptr) {
1151 return nullptr;
1152 }
1153 OopHandle* h = _initialization_error_table->get(this);
1154 return (h != nullptr) ? h->resolve() : nullptr;
1155 }
1156
1157 // Need to remove entries for unloaded classes.
1158 void InstanceKlass::clean_initialization_error_table() {
1159 struct InitErrorTableCleaner {
1160 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1161 if (!ik->is_loader_alive()) {
1162 h.release(Universe::vm_global());
1163 return true;
1164 } else {
1165 return false;
1166 }
1167 }
1168 };
1169
1170 assert_locked_or_safepoint(ClassInitError_lock);
1171 InitErrorTableCleaner cleaner;
1172 if (_initialization_error_table != nullptr) {
1173 _initialization_error_table->unlink(&cleaner);
1174 }
1175 }
1176
1177 void InstanceKlass::initialize_impl(TRAPS) {
1178 HandleMark hm(THREAD);
1179
1180 // Make sure klass is linked (verified) before initialization
1181 // A class could already be verified, since it has been reflected upon.
1182 link_class(CHECK);
1183
1184 DTRACE_CLASSINIT_PROBE(required, -1);
1185
1186 bool wait = false;
1187
1188 JavaThread* jt = THREAD;
1189
1190 if (ForceProfiling) {
1191 // Preallocate MDOs.
1192 for (int i = 0; i < methods()->length(); i++) {
1193 assert(!HAS_PENDING_EXCEPTION, "");
1194 methodHandle m(THREAD, methods()->at(i));
1195 Method::build_profiling_method_data(m, THREAD);
1196 if (HAS_PENDING_EXCEPTION) {
1197 ResourceMark rm;
1198 log_warning(cds)("MDO preallocation failed for %s", external_name());
1199 CLEAR_PENDING_EXCEPTION;
1200 break;
1201 }
1202 }
1203 }
1204
1205 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1206
1207 // refer to the JVM book page 47 for description of steps
1208 // Step 1
1209 {
1210 Handle h_init_lock(THREAD, init_lock());
1211 ObjectLocker ol(h_init_lock, jt);
1212
1213 // Step 2
1214 // If we were to use wait() instead of waitInterruptibly() then
1215 // we might end up throwing IE from link/symbol resolution sites
1216 // that aren't expected to throw. This would wreak havoc. See 6320309.
1217 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1218 if (debug_logging_enabled) {
1219 ResourceMark rm(jt);
1220 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1221 jt->name(), external_name(), init_thread_name());
1222 }
1223 wait = true;
1224 jt->set_class_to_be_initialized(this);
1225 ol.wait_uninterruptibly(jt);
1226 jt->set_class_to_be_initialized(nullptr);
1227 }
1228
1229 // Step 3
1230 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1231 if (debug_logging_enabled) {
1232 ResourceMark rm(jt);
1233 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1234 jt->name(), external_name());
1235 }
1236 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1237 return;
1238 }
1239
1240 // Step 4
1241 if (is_initialized()) {
1242 if (debug_logging_enabled) {
1243 ResourceMark rm(jt);
1244 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1245 jt->name(), external_name());
1246 }
1247 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1248 return;
1249 }
1250
1251 // Step 5
1252 if (is_in_error_state()) {
1253 if (debug_logging_enabled) {
1254 ResourceMark rm(jt);
1255 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1256 jt->name(), external_name());
1257 }
1258
1259 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1260 ResourceMark rm(THREAD);
1261 Handle cause(THREAD, get_initialization_error(THREAD));
1262
1263 stringStream ss;
1264 ss.print("Could not initialize class %s", external_name());
1265 if (cause.is_null()) {
1266 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1267 } else {
1268 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1269 ss.as_string(), cause);
1270 }
1271 } else {
1272
1273 // Step 6
1274 set_init_state(being_initialized);
1275 set_init_thread(jt);
1276 if (debug_logging_enabled) {
1277 ResourceMark rm(jt);
1278 log_debug(class, init)("Thread \"%s\" is initializing %s",
1279 jt->name(), external_name());
1280 }
1281 }
1282 }
1283
1284 // Step 7
1285 // Next, if C is a class rather than an interface, initialize it's super class and super
1286 // interfaces.
1287 if (!is_interface()) {
1288 Klass* super_klass = super();
1289 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1290 super_klass->initialize(THREAD);
1291 }
1292 // If C implements any interface that declares a non-static, concrete method,
1293 // the initialization of C triggers initialization of its super interfaces.
1294 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1295 // having a superinterface that declares, non-static, concrete methods
1296 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1297 initialize_super_interfaces(THREAD);
1298 }
1299
1300 // If any exceptions, complete abruptly, throwing the same exception as above.
1301 if (HAS_PENDING_EXCEPTION) {
1302 Handle e(THREAD, PENDING_EXCEPTION);
1303 CLEAR_PENDING_EXCEPTION;
1304 {
1305 EXCEPTION_MARK;
1306 add_initialization_error(THREAD, e);
1307 // Locks object, set state, and notify all waiting threads
1308 set_initialization_state_and_notify(initialization_error, THREAD);
1309 CLEAR_PENDING_EXCEPTION;
1310 }
1311 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1312 THROW_OOP(e());
1313 }
1314 }
1315
1316
1317 // Step 8
1318 {
1319 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1320 if (class_initializer() != nullptr) {
1321 // Timer includes any side effects of class initialization (resolution,
1322 // etc), but not recursive entry into call_class_initializer().
1323 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1324 ClassLoader::perf_class_init_selftime(),
1325 ClassLoader::perf_classes_inited(),
1326 jt->get_thread_stat()->perf_recursion_counts_addr(),
1327 jt->get_thread_stat()->perf_timers_addr(),
1328 PerfClassTraceTime::CLASS_CLINIT);
1329 call_class_initializer(THREAD);
1330 } else {
1331 // The elapsed time is so small it's not worth counting.
1332 if (UsePerfData) {
1333 ClassLoader::perf_classes_inited()->inc();
1334 }
1335 call_class_initializer(THREAD);
1336 }
1337 }
1338
1339 // Step 9
1340 if (!HAS_PENDING_EXCEPTION) {
1341 set_initialization_state_and_notify(fully_initialized, CHECK);
1342 DEBUG_ONLY(vtable().verify(tty, true);)
1343 CompilationPolicy::replay_training_at_init(this, THREAD);
1344 }
1345 else {
1346 // Step 10 and 11
1347 Handle e(THREAD, PENDING_EXCEPTION);
1348 CLEAR_PENDING_EXCEPTION;
1349 // JVMTI has already reported the pending exception
1350 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1351 JvmtiExport::clear_detected_exception(jt);
1352 {
1353 EXCEPTION_MARK;
1354 add_initialization_error(THREAD, e);
1355 set_initialization_state_and_notify(initialization_error, THREAD);
1356 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1357 // JVMTI has already reported the pending exception
1358 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1359 JvmtiExport::clear_detected_exception(jt);
1360 }
1361 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1362 if (e->is_a(vmClasses::Error_klass())) {
1363 THROW_OOP(e());
1364 } else {
1365 JavaCallArguments args(e);
1366 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1367 vmSymbols::throwable_void_signature(),
1368 &args);
1369 }
1370 }
1371 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1372 }
1373
1374 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1375 Handle h_init_lock(THREAD, init_lock());
1376 if (h_init_lock() != nullptr) {
1377 ObjectLocker ol(h_init_lock, THREAD);
1378 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1379 set_init_state(state);
1380 fence_and_clear_init_lock();
1381 ol.notify_all(CHECK);
1382 } else {
1383 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1384 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1385 set_init_state(state);
1386 }
1387 }
1388
1389 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1390 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1391 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1392 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1393
1394 DeoptimizationScope deopt_scope;
1395 {
1396 MutexLocker ml(current, Compile_lock);
1397
1398 set_init_state(InstanceKlass::loaded);
1399 // make sure init_state store is already done.
1400 // The compiler reads the hierarchy outside of the Compile_lock.
1401 // Access ordering is used to add to hierarchy.
1402
1403 // Link into hierarchy.
1404 append_to_sibling_list(); // add to superklass/sibling list
1405 process_interfaces(); // handle all "implements" declarations
1406
1407 // Now mark all code that depended on old class hierarchy.
1408 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1409 if (Universe::is_fully_initialized()) {
1410 CodeCache::mark_dependents_on(&deopt_scope, this);
1411 }
1412 }
1413 // Perform the deopt handshake outside Compile_lock.
1414 deopt_scope.deoptimize_marked();
1415 }
1416
1417
1418 InstanceKlass* InstanceKlass::implementor() const {
1419 InstanceKlass* volatile* ik = adr_implementor();
1420 if (ik == nullptr) {
1421 return nullptr;
1422 } else {
1423 // This load races with inserts, and therefore needs acquire.
1424 InstanceKlass* ikls = Atomic::load_acquire(ik);
1425 if (ikls != nullptr && !ikls->is_loader_alive()) {
1426 return nullptr; // don't return unloaded class
1427 } else {
1428 return ikls;
1429 }
1430 }
1431 }
1432
1433
1434 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1435 assert_locked_or_safepoint(Compile_lock);
1436 assert(is_interface(), "not interface");
1437 InstanceKlass* volatile* addr = adr_implementor();
1438 assert(addr != nullptr, "null addr");
1439 if (addr != nullptr) {
1440 Atomic::release_store(addr, ik);
1441 }
1442 }
1443
1444 int InstanceKlass::nof_implementors() const {
1445 InstanceKlass* ik = implementor();
1446 if (ik == nullptr) {
1447 return 0;
1448 } else if (ik != this) {
1449 return 1;
1450 } else {
1451 return 2;
1452 }
1453 }
1454
1455 // The embedded _implementor field can only record one implementor.
1456 // When there are more than one implementors, the _implementor field
1457 // is set to the interface Klass* itself. Following are the possible
1458 // values for the _implementor field:
1459 // null - no implementor
1460 // implementor Klass* - one implementor
1461 // self - more than one implementor
1462 //
1463 // The _implementor field only exists for interfaces.
1464 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1465 if (Universe::is_fully_initialized()) {
1466 assert_lock_strong(Compile_lock);
1467 }
1468 assert(is_interface(), "not interface");
1469 // Filter out my subinterfaces.
1470 // (Note: Interfaces are never on the subklass list.)
1471 if (ik->is_interface()) return;
1472
1473 // Filter out subclasses whose supers already implement me.
1474 // (Note: CHA must walk subclasses of direct implementors
1475 // in order to locate indirect implementors.)
1476 InstanceKlass* super_ik = ik->java_super();
1477 if (super_ik != nullptr && super_ik->implements_interface(this))
1478 // We only need to check one immediate superclass, since the
1479 // implements_interface query looks at transitive_interfaces.
1480 // Any supers of the super have the same (or fewer) transitive_interfaces.
1481 return;
1482
1483 InstanceKlass* iklass = implementor();
1484 if (iklass == nullptr) {
1485 set_implementor(ik);
1486 } else if (iklass != this && iklass != ik) {
1487 // There is already an implementor. Use itself as an indicator of
1488 // more than one implementors.
1489 set_implementor(this);
1490 }
1491
1492 // The implementor also implements the transitive_interfaces
1493 for (int index = 0; index < local_interfaces()->length(); index++) {
1494 local_interfaces()->at(index)->add_implementor(ik);
1495 }
1496 }
1497
1498 void InstanceKlass::init_implementor() {
1499 if (is_interface()) {
1500 set_implementor(nullptr);
1501 }
1502 }
1503
1504
1505 void InstanceKlass::process_interfaces() {
1506 // link this class into the implementors list of every interface it implements
1507 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1508 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1509 InstanceKlass* interf = local_interfaces()->at(i);
1510 assert(interf->is_interface(), "expected interface");
1511 interf->add_implementor(this);
1512 }
1513 }
1514
1515 bool InstanceKlass::can_be_primary_super_slow() const {
1516 if (is_interface())
1517 return false;
1518 else
1519 return Klass::can_be_primary_super_slow();
1520 }
1521
1522 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1523 Array<InstanceKlass*>* transitive_interfaces) {
1524 // The secondaries are the implemented interfaces.
1525 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1526 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1527 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1528 int num_secondaries = num_extra_slots + interfaces->length();
1529 if (num_secondaries == 0) {
1530 // Must share this for correct bootstrapping!
1531 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1532 return nullptr;
1533 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1534 // We will reuse the transitive interfaces list if we're certain
1535 // it's in hash order.
1536 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1537 set_secondary_supers(interfaces, bitmap);
1538 return nullptr;
1539 }
1540 // Copy transitive interfaces to a temporary growable array to be constructed
1541 // into the secondary super list with extra slots.
1542 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1543 for (int i = 0; i < interfaces->length(); i++) {
1544 secondaries->push(interfaces->at(i));
1545 }
1546 return secondaries;
1547 }
1548
1549 bool InstanceKlass::implements_interface(Klass* k) const {
1550 if (this == k) return true;
1551 assert(k->is_interface(), "should be an interface class");
1552 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1553 if (transitive_interfaces()->at(i) == k) {
1554 return true;
1555 }
1556 }
1557 return false;
1558 }
1559
1560 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1561 // Verify direct super interface
1562 if (this == k) return true;
1563 assert(k->is_interface(), "should be an interface class");
1564 for (int i = 0; i < local_interfaces()->length(); i++) {
1565 if (local_interfaces()->at(i) == k) {
1566 return true;
1567 }
1568 }
1569 return false;
1570 }
1571
1572 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1573 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1574 size_t size = objArrayOopDesc::object_size(length);
1575 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1576 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1577 /* do_zero */ true, CHECK_NULL);
1578 return o;
1579 }
1580
1581 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1582 if (TraceFinalizerRegistration) {
1583 tty->print("Registered ");
1584 i->print_value_on(tty);
1585 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1586 }
1587 instanceHandle h_i(THREAD, i);
1588 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1589 JavaValue result(T_VOID);
1590 JavaCallArguments args(h_i);
1591 methodHandle mh(THREAD, Universe::finalizer_register_method());
1592 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1593 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1594 return h_i();
1595 }
1596
1597 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1598 assert(!is_abstract() && !is_interface(), "Should not create this object");
1599 size_t size = size_helper(); // Query before forming handle.
1600 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1601 }
1602
1603 instanceOop InstanceKlass::allocate_instance(oop java_class,
1604 const char* who,
1605 TRAPS) {
1606 Klass* k = java_lang_Class::as_Klass(java_class);
1607 if (k == nullptr) {
1608 ResourceMark rm(THREAD);
1609 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1610 }
1611 InstanceKlass* ik = cast(k);
1612 ik->check_valid_for_instantiation(false, CHECK_NULL);
1613 ik->initialize(CHECK_NULL);
1614 return ik->allocate_instance(THREAD);
1615 }
1616
1617 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1618 return instanceHandle(THREAD, allocate_instance(THREAD));
1619 }
1620
1621 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1622 if (is_interface() || is_abstract()) {
1623 ResourceMark rm(THREAD);
1624 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1625 : vmSymbols::java_lang_InstantiationException(), external_name());
1626 }
1627 if (this == vmClasses::Class_klass()) {
1628 ResourceMark rm(THREAD);
1629 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1630 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1631 }
1632 }
1633
1634 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1635 // Need load-acquire for lock-free read
1636 if (array_klasses_acquire() == nullptr) {
1637
1638 // Recursively lock array allocation
1639 RecursiveLocker rl(MultiArray_lock, THREAD);
1640
1641 // Check if another thread created the array klass while we were waiting for the lock.
1642 if (array_klasses() == nullptr) {
1643 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1644 // use 'release' to pair with lock-free load
1645 release_set_array_klasses(k);
1646 }
1647 }
1648
1649 // array_klasses() will always be set at this point
1650 ObjArrayKlass* ak = array_klasses();
1651 assert(ak != nullptr, "should be set");
1652 return ak->array_klass(n, THREAD);
1653 }
1654
1655 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1656 // Need load-acquire for lock-free read
1657 ObjArrayKlass* oak = array_klasses_acquire();
1658 if (oak == nullptr) {
1659 return nullptr;
1660 } else {
1661 return oak->array_klass_or_null(n);
1662 }
1663 }
1664
1665 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1666 return array_klass(1, THREAD);
1667 }
1668
1669 ArrayKlass* InstanceKlass::array_klass_or_null() {
1670 return array_klass_or_null(1);
1671 }
1672
1673 Method* InstanceKlass::class_initializer() const {
1674 Method* clinit = find_method(
1675 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1676 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1677 return clinit;
1678 }
1679 return nullptr;
1680 }
1681
1682 void InstanceKlass::call_class_initializer(TRAPS) {
1683 if (ReplayCompiles &&
1684 (ReplaySuppressInitializers == 1 ||
1685 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1686 // Hide the existence of the initializer for the purpose of replaying the compile
1687 return;
1688 }
1689
1690 #if INCLUDE_CDS
1691 // This is needed to ensure the consistency of the archived heap objects.
1692 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1693 AOTClassInitializer::call_runtime_setup(THREAD, this);
1694 return;
1695 } else if (has_archived_enum_objs()) {
1696 assert(is_shared(), "must be");
1697 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1698 if (initialized) {
1699 return;
1700 }
1701 }
1702 #endif
1703
1704 methodHandle h_method(THREAD, class_initializer());
1705 assert(!is_initialized(), "we cannot initialize twice");
1706
1707 #if 0
1708 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1709 int init_id = log_class_init(THREAD, this);
1710 if (h_method() != nullptr) {
1711 JavaCallArguments args; // No arguments
1712 JavaValue result(T_VOID);
1713 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1714 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1715
1716 elapsedTimer timer;
1717 {
1718 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1719 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1720
1721 timer.start();
1722 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1723 timer.stop();
1724 }
1725
1726 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1727
1728 jlong bc_executed = (bc_end - bc_start);
1729 if (UsePerfData && outer == nullptr) { // outermost clinit
1730 THREAD->inc_clinit_bc_counter_value(bc_executed);
1731 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1732 }
1733
1734 THREAD->set_class_being_initialized(outer);
1735
1736 LogStreamHandle(Debug, init) log;
1737 if (log.is_enabled()) {
1738 ResourceMark rm(THREAD);
1739 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1740 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1741 if (CountBytecodes || CountBytecodesPerThread) {
1742 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1743 }
1744 name()->print_value_on(&log);
1745 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1746 p2i(THREAD), THREAD->name(), p2i(this));
1747 }
1748 }
1749 LogTarget(Info, class, init) lt;
1750 if (lt.is_enabled()) {
1751 ResourceMark rm(THREAD);
1752 LogStream ls(lt);
1753 ls.print("%d Initialized ", init_id);
1754 name()->print_value_on(&ls);
1755 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1756 h_method() == nullptr ? "(no method)" : "", p2i(this),
1757 THREAD->name());
1758 }
1759 #else
1760 static int call_class_initializer_counter = 0; // for debugging
1761 LogTarget(Info, class, init) lt;
1762 if (lt.is_enabled()) {
1763 ResourceMark rm(THREAD);
1764 LogStream ls(lt);
1765 ls.print("%d Initializing ", call_class_initializer_counter++);
1766 name()->print_value_on(&ls);
1767 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1768 h_method() == nullptr ? "(no method)" : "", p2i(this),
1769 THREAD->name());
1770 }
1771 if (h_method() != nullptr) {
1772 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1773 JavaCallArguments args; // No arguments
1774 JavaValue result(T_VOID);
1775 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1776 }
1777 #endif
1778 }
1779
1780 // If a class that implements this interface is initialized, is the JVM required
1781 // to first execute a <clinit> method declared in this interface,
1782 // or (if also_check_supers==true) any of the super types of this interface?
1783 //
1784 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1785 // an interface, then let SC be its superclass and let SI1, ..., SIn
1786 // be all superinterfaces of C (whether direct or indirect) that
1787 // declare at least one non-abstract, non-static method.
1788 //
1789 // So when an interface is initialized, it does not look at its
1790 // supers. But a proper class will ensure that all of its supers have
1791 // run their <clinit> methods, except that it disregards interfaces
1792 // that lack a non-static concrete method (i.e., a default method).
1793 // Therefore, you should probably call this method only when the
1794 // current class is a super of some proper class, not an interface.
1795 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1796 assert(is_interface(), "must be");
1797
1798 if (!has_nonstatic_concrete_methods()) {
1799 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1800 return false;
1801 }
1802
1803 // JVMS 5.5. Initialization
1804 // ...If C is an interface that declares a non-abstract,
1805 // non-static method, the initialization of a class that
1806 // implements C directly or indirectly.
1807 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1808 return true;
1809 }
1810 if (also_check_supers) {
1811 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1812 for (int i = 0; i < all_ifs->length(); ++i) {
1813 InstanceKlass* super_intf = all_ifs->at(i);
1814 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1815 return true;
1816 }
1817 }
1818 }
1819 return false;
1820 }
1821
1822 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1823 InterpreterOopMap* entry_for) {
1824 // Lazily create the _oop_map_cache at first request.
1825 // Load_acquire is needed to safely get instance published with CAS by another thread.
1826 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1827 if (oop_map_cache == nullptr) {
1828 // Try to install new instance atomically.
1829 oop_map_cache = new OopMapCache();
1830 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1831 if (other != nullptr) {
1832 // Someone else managed to install before us, ditch local copy and use the existing one.
1833 delete oop_map_cache;
1834 oop_map_cache = other;
1835 }
1836 }
1837 // _oop_map_cache is constant after init; lookup below does its own locking.
1838 oop_map_cache->lookup(method, bci, entry_for);
1839 }
1840
1841 bool InstanceKlass::contains_field_offset(int offset) {
1842 fieldDescriptor fd;
1843 return find_field_from_offset(offset, false, &fd);
1844 }
1845
1846 FieldInfo InstanceKlass::field(int index) const {
1847 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1848 if (fs.index() == index) {
1849 return fs.to_FieldInfo();
1850 }
1851 }
1852 fatal("Field not found");
1853 return FieldInfo();
1854 }
1855
1856 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1857 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1858 Symbol* f_name = fs.name();
1859 Symbol* f_sig = fs.signature();
1860 if (f_name == name && f_sig == sig) {
1861 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1862 return true;
1863 }
1864 }
1865 return false;
1866 }
1867
1868
1869 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1870 const int n = local_interfaces()->length();
1871 for (int i = 0; i < n; i++) {
1872 Klass* intf1 = local_interfaces()->at(i);
1873 assert(intf1->is_interface(), "just checking type");
1874 // search for field in current interface
1875 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1876 assert(fd->is_static(), "interface field must be static");
1877 return intf1;
1878 }
1879 // search for field in direct superinterfaces
1880 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1881 if (intf2 != nullptr) return intf2;
1882 }
1883 // otherwise field lookup fails
1884 return nullptr;
1885 }
1886
1887
1888 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1889 // search order according to newest JVM spec (5.4.3.2, p.167).
1890 // 1) search for field in current klass
1891 if (find_local_field(name, sig, fd)) {
1892 return const_cast<InstanceKlass*>(this);
1893 }
1894 // 2) search for field recursively in direct superinterfaces
1895 { Klass* intf = find_interface_field(name, sig, fd);
1896 if (intf != nullptr) return intf;
1897 }
1898 // 3) apply field lookup recursively if superclass exists
1899 { Klass* supr = super();
1900 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1901 }
1902 // 4) otherwise field lookup fails
1903 return nullptr;
1904 }
1905
1906
1907 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1908 // search order according to newest JVM spec (5.4.3.2, p.167).
1909 // 1) search for field in current klass
1910 if (find_local_field(name, sig, fd)) {
1911 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1912 }
1913 // 2) search for field recursively in direct superinterfaces
1914 if (is_static) {
1915 Klass* intf = find_interface_field(name, sig, fd);
1916 if (intf != nullptr) return intf;
1917 }
1918 // 3) apply field lookup recursively if superclass exists
1919 { Klass* supr = super();
1920 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1921 }
1922 // 4) otherwise field lookup fails
1923 return nullptr;
1924 }
1925
1926
1927 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1928 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1929 if (fs.offset() == offset) {
1930 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1931 if (fd->is_static() == is_static) return true;
1932 }
1933 }
1934 return false;
1935 }
1936
1937
1938 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1939 Klass* klass = const_cast<InstanceKlass*>(this);
1940 while (klass != nullptr) {
1941 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1942 return true;
1943 }
1944 klass = klass->super();
1945 }
1946 return false;
1947 }
1948
1949
1950 void InstanceKlass::methods_do(void f(Method* method)) {
1951 // Methods aren't stable until they are loaded. This can be read outside
1952 // a lock through the ClassLoaderData for profiling
1953 // Redefined scratch classes are on the list and need to be cleaned
1954 if (!is_loaded() && !is_scratch_class()) {
1955 return;
1956 }
1957
1958 int len = methods()->length();
1959 for (int index = 0; index < len; index++) {
1960 Method* m = methods()->at(index);
1961 assert(m->is_method(), "must be method");
1962 f(m);
1963 }
1964 }
1965
1966
1967 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1968 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1969 if (fs.access_flags().is_static()) {
1970 fieldDescriptor& fd = fs.field_descriptor();
1971 cl->do_field(&fd);
1972 }
1973 }
1974 }
1975
1976
1977 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1978 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1979 if (fs.access_flags().is_static()) {
1980 fieldDescriptor& fd = fs.field_descriptor();
1981 f(&fd, mirror, CHECK);
1982 }
1983 }
1984 }
1985
1986 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1987 InstanceKlass* super = superklass();
1988 if (super != nullptr) {
1989 super->do_nonstatic_fields(cl);
1990 }
1991 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1992 fieldDescriptor& fd = fs.field_descriptor();
1993 if (!fd.is_static()) {
1994 cl->do_field(&fd);
1995 }
1996 }
1997 }
1998
1999 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2000 return a->offset() - b->offset();
2001 }
2002
2003 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2004 InstanceKlass* super = superklass();
2005 if (super != nullptr) {
2006 super->print_nonstatic_fields(cl);
2007 }
2008 ResourceMark rm;
2009 // In DebugInfo nonstatic fields are sorted by offset.
2010 GrowableArray<FieldInfo> fields_sorted;
2011 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2012 if (!fs.access_flags().is_static()) {
2013 fields_sorted.push(fs.to_FieldInfo());
2014 }
2015 }
2016 int length = fields_sorted.length();
2017 if (length > 0) {
2018 fields_sorted.sort(compare_fields_by_offset);
2019 fieldDescriptor fd;
2020 for (int i = 0; i < length; i++) {
2021 fd.reinitialize(this, fields_sorted.at(i));
2022 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2023 cl->do_field(&fd);
2024 }
2025 }
2026 }
2027
2028 #ifdef ASSERT
2029 static int linear_search(const Array<Method*>* methods,
2030 const Symbol* name,
2031 const Symbol* signature) {
2032 const int len = methods->length();
2033 for (int index = 0; index < len; index++) {
2034 const Method* const m = methods->at(index);
2035 assert(m->is_method(), "must be method");
2036 if (m->signature() == signature && m->name() == name) {
2037 return index;
2038 }
2039 }
2040 return -1;
2041 }
2042 #endif
2043
2044 bool InstanceKlass::_disable_method_binary_search = false;
2045
2046 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2047 int len = methods->length();
2048 int l = 0;
2049 int h = len - 1;
2050 while (l <= h) {
2051 Method* m = methods->at(l);
2052 if (m->name() == name) {
2053 return l;
2054 }
2055 l++;
2056 }
2057 return -1;
2058 }
2059
2060 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2061 if (_disable_method_binary_search) {
2062 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2063 // At the final stage of dynamic dumping, the methods array may not be sorted
2064 // by ascending addresses of their names, so we can't use binary search anymore.
2065 // However, methods with the same name are still laid out consecutively inside the
2066 // methods array, so let's look for the first one that matches.
2067 return linear_search(methods, name);
2068 }
2069
2070 int len = methods->length();
2071 int l = 0;
2072 int h = len - 1;
2073
2074 // methods are sorted by ascending addresses of their names, so do binary search
2075 while (l <= h) {
2076 int mid = (l + h) >> 1;
2077 Method* m = methods->at(mid);
2078 assert(m->is_method(), "must be method");
2079 int res = m->name()->fast_compare(name);
2080 if (res == 0) {
2081 return mid;
2082 } else if (res < 0) {
2083 l = mid + 1;
2084 } else {
2085 h = mid - 1;
2086 }
2087 }
2088 return -1;
2089 }
2090
2091 // find_method looks up the name/signature in the local methods array
2092 Method* InstanceKlass::find_method(const Symbol* name,
2093 const Symbol* signature) const {
2094 return find_method_impl(name, signature,
2095 OverpassLookupMode::find,
2096 StaticLookupMode::find,
2097 PrivateLookupMode::find);
2098 }
2099
2100 Method* InstanceKlass::find_method_impl(const Symbol* name,
2101 const Symbol* signature,
2102 OverpassLookupMode overpass_mode,
2103 StaticLookupMode static_mode,
2104 PrivateLookupMode private_mode) const {
2105 return InstanceKlass::find_method_impl(methods(),
2106 name,
2107 signature,
2108 overpass_mode,
2109 static_mode,
2110 private_mode);
2111 }
2112
2113 // find_instance_method looks up the name/signature in the local methods array
2114 // and skips over static methods
2115 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2116 const Symbol* name,
2117 const Symbol* signature,
2118 PrivateLookupMode private_mode) {
2119 Method* const meth = InstanceKlass::find_method_impl(methods,
2120 name,
2121 signature,
2122 OverpassLookupMode::find,
2123 StaticLookupMode::skip,
2124 private_mode);
2125 assert(((meth == nullptr) || !meth->is_static()),
2126 "find_instance_method should have skipped statics");
2127 return meth;
2128 }
2129
2130 // find_instance_method looks up the name/signature in the local methods array
2131 // and skips over static methods
2132 Method* InstanceKlass::find_instance_method(const Symbol* name,
2133 const Symbol* signature,
2134 PrivateLookupMode private_mode) const {
2135 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2136 }
2137
2138 // Find looks up the name/signature in the local methods array
2139 // and filters on the overpass, static and private flags
2140 // This returns the first one found
2141 // note that the local methods array can have up to one overpass, one static
2142 // and one instance (private or not) with the same name/signature
2143 Method* InstanceKlass::find_local_method(const Symbol* name,
2144 const Symbol* signature,
2145 OverpassLookupMode overpass_mode,
2146 StaticLookupMode static_mode,
2147 PrivateLookupMode private_mode) const {
2148 return InstanceKlass::find_method_impl(methods(),
2149 name,
2150 signature,
2151 overpass_mode,
2152 static_mode,
2153 private_mode);
2154 }
2155
2156 // Find looks up the name/signature in the local methods array
2157 // and filters on the overpass, static and private flags
2158 // This returns the first one found
2159 // note that the local methods array can have up to one overpass, one static
2160 // and one instance (private or not) with the same name/signature
2161 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2162 const Symbol* name,
2163 const Symbol* signature,
2164 OverpassLookupMode overpass_mode,
2165 StaticLookupMode static_mode,
2166 PrivateLookupMode private_mode) {
2167 return InstanceKlass::find_method_impl(methods,
2168 name,
2169 signature,
2170 overpass_mode,
2171 static_mode,
2172 private_mode);
2173 }
2174
2175 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2176 const Symbol* name,
2177 const Symbol* signature) {
2178 return InstanceKlass::find_method_impl(methods,
2179 name,
2180 signature,
2181 OverpassLookupMode::find,
2182 StaticLookupMode::find,
2183 PrivateLookupMode::find);
2184 }
2185
2186 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2187 const Symbol* name,
2188 const Symbol* signature,
2189 OverpassLookupMode overpass_mode,
2190 StaticLookupMode static_mode,
2191 PrivateLookupMode private_mode) {
2192 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2193 return hit >= 0 ? methods->at(hit): nullptr;
2194 }
2195
2196 // true if method matches signature and conforms to skipping_X conditions.
2197 static bool method_matches(const Method* m,
2198 const Symbol* signature,
2199 bool skipping_overpass,
2200 bool skipping_static,
2201 bool skipping_private) {
2202 return ((m->signature() == signature) &&
2203 (!skipping_overpass || !m->is_overpass()) &&
2204 (!skipping_static || !m->is_static()) &&
2205 (!skipping_private || !m->is_private()));
2206 }
2207
2208 // Used directly for default_methods to find the index into the
2209 // default_vtable_indices, and indirectly by find_method
2210 // find_method_index looks in the local methods array to return the index
2211 // of the matching name/signature. If, overpass methods are being ignored,
2212 // the search continues to find a potential non-overpass match. This capability
2213 // is important during method resolution to prefer a static method, for example,
2214 // over an overpass method.
2215 // There is the possibility in any _method's array to have the same name/signature
2216 // for a static method, an overpass method and a local instance method
2217 // To correctly catch a given method, the search criteria may need
2218 // to explicitly skip the other two. For local instance methods, it
2219 // is often necessary to skip private methods
2220 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2221 const Symbol* name,
2222 const Symbol* signature,
2223 OverpassLookupMode overpass_mode,
2224 StaticLookupMode static_mode,
2225 PrivateLookupMode private_mode) {
2226 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2227 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2228 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2229 const int hit = quick_search(methods, name);
2230 if (hit != -1) {
2231 const Method* const m = methods->at(hit);
2232
2233 // Do linear search to find matching signature. First, quick check
2234 // for common case, ignoring overpasses if requested.
2235 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2236 return hit;
2237 }
2238
2239 // search downwards through overloaded methods
2240 int i;
2241 for (i = hit - 1; i >= 0; --i) {
2242 const Method* const m = methods->at(i);
2243 assert(m->is_method(), "must be method");
2244 if (m->name() != name) {
2245 break;
2246 }
2247 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2248 return i;
2249 }
2250 }
2251 // search upwards
2252 for (i = hit + 1; i < methods->length(); ++i) {
2253 const Method* const m = methods->at(i);
2254 assert(m->is_method(), "must be method");
2255 if (m->name() != name) {
2256 break;
2257 }
2258 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2259 return i;
2260 }
2261 }
2262 // not found
2263 #ifdef ASSERT
2264 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2265 linear_search(methods, name, signature);
2266 assert(-1 == index, "binary search should have found entry %d", index);
2267 #endif
2268 }
2269 return -1;
2270 }
2271
2272 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2273 return find_method_by_name(methods(), name, end);
2274 }
2275
2276 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2277 const Symbol* name,
2278 int* end_ptr) {
2279 assert(end_ptr != nullptr, "just checking");
2280 int start = quick_search(methods, name);
2281 int end = start + 1;
2282 if (start != -1) {
2283 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2284 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2285 *end_ptr = end;
2286 return start;
2287 }
2288 return -1;
2289 }
2290
2291 // uncached_lookup_method searches both the local class methods array and all
2292 // superclasses methods arrays, skipping any overpass methods in superclasses,
2293 // and possibly skipping private methods.
2294 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2295 const Symbol* signature,
2296 OverpassLookupMode overpass_mode,
2297 PrivateLookupMode private_mode) const {
2298 OverpassLookupMode overpass_local_mode = overpass_mode;
2299 const Klass* klass = this;
2300 while (klass != nullptr) {
2301 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2302 signature,
2303 overpass_local_mode,
2304 StaticLookupMode::find,
2305 private_mode);
2306 if (method != nullptr) {
2307 return method;
2308 }
2309 klass = klass->super();
2310 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2311 }
2312 return nullptr;
2313 }
2314
2315 #ifdef ASSERT
2316 // search through class hierarchy and return true if this class or
2317 // one of the superclasses was redefined
2318 bool InstanceKlass::has_redefined_this_or_super() const {
2319 const Klass* klass = this;
2320 while (klass != nullptr) {
2321 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2322 return true;
2323 }
2324 klass = klass->super();
2325 }
2326 return false;
2327 }
2328 #endif
2329
2330 // lookup a method in the default methods list then in all transitive interfaces
2331 // Do NOT return private or static methods
2332 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2333 Symbol* signature) const {
2334 Method* m = nullptr;
2335 if (default_methods() != nullptr) {
2336 m = find_method(default_methods(), name, signature);
2337 }
2338 // Look up interfaces
2339 if (m == nullptr) {
2340 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2341 }
2342 return m;
2343 }
2344
2345 // lookup a method in all the interfaces that this class implements
2346 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2347 // They should only be found in the initial InterfaceMethodRef
2348 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2349 Symbol* signature,
2350 DefaultsLookupMode defaults_mode) const {
2351 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2352 int num_ifs = all_ifs->length();
2353 InstanceKlass *ik = nullptr;
2354 for (int i = 0; i < num_ifs; i++) {
2355 ik = all_ifs->at(i);
2356 Method* m = ik->lookup_method(name, signature);
2357 if (m != nullptr && m->is_public() && !m->is_static() &&
2358 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2359 return m;
2360 }
2361 }
2362 return nullptr;
2363 }
2364
2365 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2366 :_st(st), _verbose(verbose) {
2367 ResourceMark rm;
2368 _st->print("%-18s ", "KlassAddr");
2369 _st->print("%-4s ", "Size");
2370 _st->print("%-20s ", "State");
2371 _st->print("%-7s ", "Flags");
2372 _st->print("%-5s ", "ClassName");
2373 _st->cr();
2374 }
2375
2376 void PrintClassClosure::do_klass(Klass* k) {
2377 ResourceMark rm;
2378 // klass pointer
2379 _st->print(PTR_FORMAT " ", p2i(k));
2380 // klass size
2381 _st->print("%4d ", k->size());
2382 // initialization state
2383 if (k->is_instance_klass()) {
2384 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2385 } else {
2386 _st->print("%-20s ","");
2387 }
2388 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2389 char buf[10];
2390 int i = 0;
2391 if (k->has_finalizer()) buf[i++] = 'F';
2392 if (k->is_instance_klass()) {
2393 InstanceKlass* ik = InstanceKlass::cast(k);
2394 if (ik->has_final_method()) buf[i++] = 'f';
2395 if (ik->is_rewritten()) buf[i++] = 'W';
2396 if (ik->is_contended()) buf[i++] = 'C';
2397 if (ik->has_been_redefined()) buf[i++] = 'R';
2398 if (ik->is_shared()) buf[i++] = 'S';
2399 }
2400 buf[i++] = '\0';
2401 _st->print("%-7s ", buf);
2402 // klass name
2403 _st->print("%-5s ", k->external_name());
2404 // end
2405 _st->cr();
2406 if (_verbose) {
2407 k->print_on(_st);
2408 }
2409 }
2410
2411 /* jni_id_for for jfieldIds only */
2412 JNIid* InstanceKlass::jni_id_for(int offset) {
2413 MutexLocker ml(JfieldIdCreation_lock);
2414 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2415 if (probe == nullptr) {
2416 // Allocate new static field identifier
2417 probe = new JNIid(this, offset, jni_ids());
2418 set_jni_ids(probe);
2419 }
2420 return probe;
2421 }
2422
2423 u2 InstanceKlass::enclosing_method_data(int offset) const {
2424 const Array<jushort>* const inner_class_list = inner_classes();
2425 if (inner_class_list == nullptr) {
2426 return 0;
2427 }
2428 const int length = inner_class_list->length();
2429 if (length % inner_class_next_offset == 0) {
2430 return 0;
2431 }
2432 const int index = length - enclosing_method_attribute_size;
2433 assert(offset < enclosing_method_attribute_size, "invalid offset");
2434 return inner_class_list->at(index + offset);
2435 }
2436
2437 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2438 u2 method_index) {
2439 Array<jushort>* inner_class_list = inner_classes();
2440 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2441 int length = inner_class_list->length();
2442 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2443 int index = length - enclosing_method_attribute_size;
2444 inner_class_list->at_put(
2445 index + enclosing_method_class_index_offset, class_index);
2446 inner_class_list->at_put(
2447 index + enclosing_method_method_index_offset, method_index);
2448 }
2449 }
2450
2451 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2452 if (method->is_old() && !method->is_obsolete()) {
2453 // If the method passed in is old (but not obsolete), use the current version.
2454 method = method_with_idnum((int)idnum);
2455 assert(method != nullptr, "old and but not obsolete, so should exist");
2456 }
2457 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2458 Atomic::release_store(&jmeths[idnum + 1], new_id);
2459 return new_id;
2460 }
2461
2462 // Lookup or create a jmethodID.
2463 // This code is called by the VMThread and JavaThreads so the
2464 // locking has to be done very carefully to avoid deadlocks
2465 // and/or other cache consistency problems.
2466 //
2467 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2468 Method* method = method_h();
2469 int idnum = method->method_idnum();
2470 jmethodID* jmeths = methods_jmethod_ids_acquire();
2471
2472 // We use a double-check locking idiom here because this cache is
2473 // performance sensitive. In the normal system, this cache only
2474 // transitions from null to non-null which is safe because we use
2475 // release_set_methods_jmethod_ids() to advertise the new cache.
2476 // A partially constructed cache should never be seen by a racing
2477 // thread. We also use release_store() to save a new jmethodID
2478 // in the cache so a partially constructed jmethodID should never be
2479 // seen either. Cache reads of existing jmethodIDs proceed without a
2480 // lock, but cache writes of a new jmethodID requires uniqueness and
2481 // creation of the cache itself requires no leaks so a lock is
2482 // acquired in those two cases.
2483 //
2484 // If the RedefineClasses() API has been used, then this cache grows
2485 // in the redefinition safepoint.
2486
2487 if (jmeths == nullptr) {
2488 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2489 jmeths = methods_jmethod_ids_acquire();
2490 // Still null?
2491 if (jmeths == nullptr) {
2492 size_t size = idnum_allocated_count();
2493 assert(size > (size_t)idnum, "should already have space");
2494 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2495 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2496 // cache size is stored in element[0], other elements offset by one
2497 jmeths[0] = (jmethodID)size;
2498 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2499
2500 // publish jmeths
2501 release_set_methods_jmethod_ids(jmeths);
2502 return new_id;
2503 }
2504 }
2505
2506 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2507 if (id == nullptr) {
2508 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2509 id = jmeths[idnum + 1];
2510 // Still null?
2511 if (id == nullptr) {
2512 return update_jmethod_id(jmeths, method, idnum);
2513 }
2514 }
2515 return id;
2516 }
2517
2518 void InstanceKlass::update_methods_jmethod_cache() {
2519 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2520 jmethodID* cache = _methods_jmethod_ids;
2521 if (cache != nullptr) {
2522 size_t size = idnum_allocated_count();
2523 size_t old_size = (size_t)cache[0];
2524 if (old_size < size + 1) {
2525 // Allocate a larger one and copy entries to the new one.
2526 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2527 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2528 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2529 // The cache size is stored in element[0]; the other elements are offset by one.
2530 new_cache[0] = (jmethodID)size;
2531
2532 for (int i = 1; i <= (int)old_size; i++) {
2533 new_cache[i] = cache[i];
2534 }
2535 _methods_jmethod_ids = new_cache;
2536 FREE_C_HEAP_ARRAY(jmethodID, cache);
2537 }
2538 }
2539 }
2540
2541 // Figure out how many jmethodIDs haven't been allocated, and make
2542 // sure space for them is pre-allocated. This makes getting all
2543 // method ids much, much faster with classes with more than 8
2544 // methods, and has a *substantial* effect on performance with jvmti
2545 // code that loads all jmethodIDs for all classes.
2546 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2547 int new_jmeths = 0;
2548 int length = methods()->length();
2549 for (int index = start_offset; index < length; index++) {
2550 Method* m = methods()->at(index);
2551 jmethodID id = m->find_jmethod_id_or_null();
2552 if (id == nullptr) {
2553 new_jmeths++;
2554 }
2555 }
2556 if (new_jmeths != 0) {
2557 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2558 }
2559 }
2560
2561 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2562 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2563 int idnum = method->method_idnum();
2564 jmethodID* jmeths = methods_jmethod_ids_acquire();
2565 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2566 }
2567
2568 inline DependencyContext InstanceKlass::dependencies() {
2569 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2570 return dep_context;
2571 }
2572
2573 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2574 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2575 }
2576
2577 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2578 assert_lock_strong(CodeCache_lock);
2579 dependencies().add_dependent_nmethod(nm);
2580 }
2581
2582 void InstanceKlass::clean_dependency_context() {
2583 dependencies().clean_unloading_dependents();
2584 }
2585
2586 #ifndef PRODUCT
2587 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2588 dependencies().print_dependent_nmethods(verbose);
2589 }
2590
2591 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2592 return dependencies().is_dependent_nmethod(nm);
2593 }
2594 #endif //PRODUCT
2595
2596 void InstanceKlass::clean_weak_instanceklass_links() {
2597 clean_implementors_list();
2598 clean_method_data();
2599 }
2600
2601 void InstanceKlass::clean_implementors_list() {
2602 assert(is_loader_alive(), "this klass should be live");
2603 if (is_interface()) {
2604 assert (ClassUnloading, "only called for ClassUnloading");
2605 for (;;) {
2606 // Use load_acquire due to competing with inserts
2607 InstanceKlass* volatile* iklass = adr_implementor();
2608 assert(iklass != nullptr, "Klass must not be null");
2609 InstanceKlass* impl = Atomic::load_acquire(iklass);
2610 if (impl != nullptr && !impl->is_loader_alive()) {
2611 // null this field, might be an unloaded instance klass or null
2612 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2613 // Successfully unlinking implementor.
2614 if (log_is_enabled(Trace, class, unload)) {
2615 ResourceMark rm;
2616 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2617 }
2618 return;
2619 }
2620 } else {
2621 return;
2622 }
2623 }
2624 }
2625 }
2626
2627 void InstanceKlass::clean_method_data() {
2628 for (int m = 0; m < methods()->length(); m++) {
2629 MethodData* mdo = methods()->at(m)->method_data();
2630 if (mdo != nullptr) {
2631 mdo->clean_method_data(/*always_clean*/false);
2632 }
2633 }
2634 }
2635
2636 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2637 Klass::metaspace_pointers_do(it);
2638
2639 if (log_is_enabled(Trace, cds)) {
2640 ResourceMark rm;
2641 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2642 }
2643
2644 it->push(&_annotations);
2645 it->push((Klass**)&_array_klasses);
2646 if (!is_rewritten()) {
2647 it->push(&_constants, MetaspaceClosure::_writable);
2648 } else {
2649 it->push(&_constants);
2650 }
2651 it->push(&_inner_classes);
2652 #if INCLUDE_JVMTI
2653 it->push(&_previous_versions);
2654 #endif
2655 #if INCLUDE_CDS
2656 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2657 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2658 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2659 // The length check on the _methods is necessary because classes which don't have any
2660 // methods share the Universe::_the_empty_method_array which is in the RO region.
2661 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2662 // To handle jsr bytecode, new Method* maybe stored into _methods
2663 it->push(&_methods, MetaspaceClosure::_writable);
2664 } else {
2665 #endif
2666 it->push(&_methods);
2667 #if INCLUDE_CDS
2668 }
2669 #endif
2670 it->push(&_default_methods);
2671 it->push(&_local_interfaces);
2672 it->push(&_transitive_interfaces);
2673 it->push(&_method_ordering);
2674 if (!is_rewritten()) {
2675 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2676 } else {
2677 it->push(&_default_vtable_indices);
2678 }
2679
2680 it->push(&_fieldinfo_stream);
2681 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2682 it->push(&_fields_status, MetaspaceClosure::_writable);
2683
2684 if (itable_length() > 0) {
2685 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2686 int method_table_offset_in_words = ioe->offset()/wordSize;
2687 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2688
2689 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2690 / itableOffsetEntry::size();
2691
2692 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2693 if (ioe->interface_klass() != nullptr) {
2694 it->push(ioe->interface_klass_addr());
2695 itableMethodEntry* ime = ioe->first_method_entry(this);
2696 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2697 for (int index = 0; index < n; index ++) {
2698 it->push(ime[index].method_addr());
2699 }
2700 }
2701 }
2702 }
2703
2704 it->push(&_nest_host);
2705 it->push(&_nest_members);
2706 it->push(&_permitted_subclasses);
2707 it->push(&_record_components);
2708 }
2709
2710 #if INCLUDE_CDS
2711 void InstanceKlass::remove_unshareable_info() {
2712 if (is_linked()) {
2713 assert(can_be_verified_at_dumptime(), "must be");
2714 // Remember this so we can avoid walking the hierarchy at runtime.
2715 set_verified_at_dump_time();
2716 }
2717 _misc_flags.set_has_init_deps_processed(false);
2718
2719 Klass::remove_unshareable_info();
2720
2721 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2722 // Classes are attempted to link during dumping and may fail,
2723 // but these classes are still in the dictionary and class list in CLD.
2724 // If the class has failed verification, there is nothing else to remove.
2725 return;
2726 }
2727
2728 // Reset to the 'allocated' state to prevent any premature accessing to
2729 // a shared class at runtime while the class is still being loaded and
2730 // restored. A class' init_state is set to 'loaded' at runtime when it's
2731 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2732 _init_state = allocated;
2733
2734 { // Otherwise this needs to take out the Compile_lock.
2735 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2736 init_implementor();
2737 }
2738
2739 // Call remove_unshareable_info() on other objects that belong to this class, except
2740 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2741 // ArchiveBuilder::make_klasses_shareable(),
2742
2743 for (int i = 0; i < methods()->length(); i++) {
2744 Method* m = methods()->at(i);
2745 m->remove_unshareable_info();
2746 }
2747
2748 // do array classes also.
2749 if (array_klasses() != nullptr) {
2750 array_klasses()->remove_unshareable_info();
2751 }
2752
2753 // These are not allocated from metaspace. They are safe to set to null.
2754 _source_debug_extension = nullptr;
2755 _dep_context = nullptr;
2756 _osr_nmethods_head = nullptr;
2757 #if INCLUDE_JVMTI
2758 _breakpoints = nullptr;
2759 _previous_versions = nullptr;
2760 _cached_class_file = nullptr;
2761 _jvmti_cached_class_field_map = nullptr;
2762 #endif
2763
2764 _init_thread = nullptr;
2765 _methods_jmethod_ids = nullptr;
2766 _jni_ids = nullptr;
2767 _oop_map_cache = nullptr;
2768 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2769 // keep _nest_host
2770 } else {
2771 // clear _nest_host to ensure re-load at runtime
2772 _nest_host = nullptr;
2773 }
2774 init_shared_package_entry();
2775 _dep_context_last_cleaned = 0;
2776 DEBUG_ONLY(_shared_class_load_count = 0);
2777
2778 remove_unshareable_flags();
2779 }
2780
2781 void InstanceKlass::remove_unshareable_flags() {
2782 // clear all the flags/stats that shouldn't be in the archived version
2783 assert(!is_scratch_class(), "must be");
2784 assert(!has_been_redefined(), "must be");
2785 #if INCLUDE_JVMTI
2786 set_is_being_redefined(false);
2787 #endif
2788 set_has_resolved_methods(false);
2789 }
2790
2791 void InstanceKlass::remove_java_mirror() {
2792 Klass::remove_java_mirror();
2793
2794 // do array classes also.
2795 if (array_klasses() != nullptr) {
2796 array_klasses()->remove_java_mirror();
2797 }
2798 }
2799
2800 void InstanceKlass::init_shared_package_entry() {
2801 assert(CDSConfig::is_dumping_archive(), "must be");
2802 #if !INCLUDE_CDS_JAVA_HEAP
2803 _package_entry = nullptr;
2804 #else
2805 if (CDSConfig::is_dumping_full_module_graph()) {
2806 if (is_shared_unregistered_class()) {
2807 _package_entry = nullptr;
2808 } else {
2809 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2810 }
2811 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2812 CDSConfig::is_using_full_module_graph() &&
2813 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2814 // _package_entry is an archived package in the base archive. Leave it as is.
2815 } else {
2816 _package_entry = nullptr;
2817 }
2818 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2819 #endif
2820 }
2821
2822 void InstanceKlass::compute_has_loops_flag_for_methods() {
2823 Array<Method*>* methods = this->methods();
2824 for (int index = 0; index < methods->length(); ++index) {
2825 Method* m = methods->at(index);
2826 if (!m->is_overpass()) { // work around JDK-8305771
2827 m->compute_has_loops_flag();
2828 }
2829 }
2830 }
2831
2832 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2833 PackageEntry* pkg_entry, TRAPS) {
2834 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2835 // before the InstanceKlass is added to the SystemDictionary. Make
2836 // sure the current state is <loaded.
2837 assert(!is_loaded(), "invalid init state");
2838 assert(!shared_loading_failed(), "Must not try to load failed class again");
2839 set_package(loader_data, pkg_entry, CHECK);
2840 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2841
2842 Array<Method*>* methods = this->methods();
2843 int num_methods = methods->length();
2844 for (int index = 0; index < num_methods; ++index) {
2845 methods->at(index)->restore_unshareable_info(CHECK);
2846 }
2847 #if INCLUDE_JVMTI
2848 if (JvmtiExport::has_redefined_a_class()) {
2849 // Reinitialize vtable because RedefineClasses may have changed some
2850 // entries in this vtable for super classes so the CDS vtable might
2851 // point to old or obsolete entries. RedefineClasses doesn't fix up
2852 // vtables in the shared system dictionary, only the main one.
2853 // It also redefines the itable too so fix that too.
2854 // First fix any default methods that point to a super class that may
2855 // have been redefined.
2856 bool trace_name_printed = false;
2857 adjust_default_methods(&trace_name_printed);
2858 if (verified_at_dump_time()) {
2859 // Initialize vtable and itable for classes which can be verified at dump time.
2860 // Unlinked classes such as old classes with major version < 50 cannot be verified
2861 // at dump time.
2862 vtable().initialize_vtable();
2863 itable().initialize_itable();
2864 }
2865 }
2866 #endif // INCLUDE_JVMTI
2867
2868 // restore constant pool resolved references
2869 constants()->restore_unshareable_info(CHECK);
2870
2871 if (array_klasses() != nullptr) {
2872 // To get a consistent list of classes we need MultiArray_lock to ensure
2873 // array classes aren't observed while they are being restored.
2874 RecursiveLocker rl(MultiArray_lock, THREAD);
2875 assert(this == array_klasses()->bottom_klass(), "sanity");
2876 // Array classes have null protection domain.
2877 // --> see ArrayKlass::complete_create_array_klass()
2878 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2879 }
2880
2881 // Initialize @ValueBased class annotation if not already set in the archived klass.
2882 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2883 set_is_value_based();
2884 }
2885 }
2886
2887 bool InstanceKlass::can_be_verified_at_dumptime() const {
2888 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2889 return true;
2890 }
2891
2892 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2893 // This is a class that was dumped into the base archive, so we know
2894 // it was verified at dump time.
2895 return true;
2896 }
2897
2898 // Check if a class or any of its supertypes has a version older than 50.
2899 // CDS will not perform verification of old classes during dump time because
2900 // without changing the old verifier, the verification constraint cannot be
2901 // retrieved during dump time.
2902 // Verification of archived old classes will be performed during run time.
2903 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2904 return false;
2905 }
2906 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2907 return false;
2908 }
2909 Array<InstanceKlass*>* interfaces = local_interfaces();
2910 int len = interfaces->length();
2911 for (int i = 0; i < len; i++) {
2912 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2913 return false;
2914 }
2915 }
2916 return true;
2917 }
2918
2919 int InstanceKlass::shared_class_loader_type() const {
2920 if (is_shared_boot_class()) {
2921 return ClassLoader::BOOT_LOADER;
2922 } else if (is_shared_platform_class()) {
2923 return ClassLoader::PLATFORM_LOADER;
2924 } else if (is_shared_app_class()) {
2925 return ClassLoader::APP_LOADER;
2926 } else {
2927 return ClassLoader::OTHER;
2928 }
2929 }
2930
2931 #endif // INCLUDE_CDS
2932
2933 #if INCLUDE_JVMTI
2934 static void clear_all_breakpoints(Method* m) {
2935 m->clear_all_breakpoints();
2936 }
2937 #endif
2938
2939 void InstanceKlass::unload_class(InstanceKlass* ik) {
2940
2941 if (ik->is_scratch_class()) {
2942 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2943 return;
2944 }
2945 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2946
2947 // Release dependencies.
2948 ik->dependencies().remove_all_dependents();
2949
2950 // notify the debugger
2951 if (JvmtiExport::should_post_class_unload()) {
2952 JvmtiExport::post_class_unload(ik);
2953 }
2954
2955 // notify ClassLoadingService of class unload
2956 ClassLoadingService::notify_class_unloaded(ik);
2957
2958 SystemDictionaryShared::handle_class_unloading(ik);
2959
2960 if (log_is_enabled(Info, class, unload)) {
2961 ResourceMark rm;
2962 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2963 }
2964
2965 Events::log_class_unloading(Thread::current(), ik);
2966
2967 #if INCLUDE_JFR
2968 assert(ik != nullptr, "invariant");
2969 EventClassUnload event;
2970 event.set_unloadedClass(ik);
2971 event.set_definingClassLoader(ik->class_loader_data());
2972 event.commit();
2973 #endif
2974 }
2975
2976 static void method_release_C_heap_structures(Method* m) {
2977 m->release_C_heap_structures();
2978 }
2979
2980 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2981 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2982 // Clean up C heap
2983 Klass::release_C_heap_structures();
2984
2985 // Deallocate and call destructors for MDO mutexes
2986 if (release_sub_metadata) {
2987 methods_do(method_release_C_heap_structures);
2988 }
2989
2990 // Deallocate oop map cache
2991 if (_oop_map_cache != nullptr) {
2992 delete _oop_map_cache;
2993 _oop_map_cache = nullptr;
2994 }
2995
2996 // Deallocate JNI identifiers for jfieldIDs
2997 JNIid::deallocate(jni_ids());
2998 set_jni_ids(nullptr);
2999
3000 jmethodID* jmeths = methods_jmethod_ids_acquire();
3001 if (jmeths != nullptr) {
3002 release_set_methods_jmethod_ids(nullptr);
3003 FreeHeap(jmeths);
3004 }
3005
3006 assert(_dep_context == nullptr,
3007 "dependencies should already be cleaned");
3008
3009 #if INCLUDE_JVMTI
3010 // Deallocate breakpoint records
3011 if (breakpoints() != nullptr) {
3012 methods_do(clear_all_breakpoints);
3013 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3014 }
3015
3016 // deallocate the cached class file
3017 if (_cached_class_file != nullptr) {
3018 os::free(_cached_class_file);
3019 _cached_class_file = nullptr;
3020 }
3021 #endif
3022
3023 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3024
3025 if (release_sub_metadata) {
3026 constants()->release_C_heap_structures();
3027 }
3028 }
3029
3030 // The constant pool is on stack if any of the methods are executing or
3031 // referenced by handles.
3032 bool InstanceKlass::on_stack() const {
3033 return _constants->on_stack();
3034 }
3035
3036 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3037 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3038 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3039
3040 // minor and major version numbers of class file
3041 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3042 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3043 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3044 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3045
3046 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3047 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3048 if (ik->constants()->version() == version) {
3049 return ik;
3050 }
3051 }
3052 return nullptr;
3053 }
3054
3055 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3056 if (array == nullptr) {
3057 _source_debug_extension = nullptr;
3058 } else {
3059 // Adding one to the attribute length in order to store a null terminator
3060 // character could cause an overflow because the attribute length is
3061 // already coded with an u4 in the classfile, but in practice, it's
3062 // unlikely to happen.
3063 assert((length+1) > length, "Overflow checking");
3064 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3065 for (int i = 0; i < length; i++) {
3066 sde[i] = array[i];
3067 }
3068 sde[length] = '\0';
3069 _source_debug_extension = sde;
3070 }
3071 }
3072
3073 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3074 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3075 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3076
3077 const char* InstanceKlass::signature_name() const {
3078
3079 // Get the internal name as a c string
3080 const char* src = (const char*) (name()->as_C_string());
3081 const int src_length = (int)strlen(src);
3082
3083 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3084
3085 // Add L as type indicator
3086 int dest_index = 0;
3087 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3088
3089 // Add the actual class name
3090 for (int src_index = 0; src_index < src_length; ) {
3091 dest[dest_index++] = src[src_index++];
3092 }
3093
3094 if (is_hidden()) { // Replace the last '+' with a '.'.
3095 for (int index = (int)src_length; index > 0; index--) {
3096 if (dest[index] == '+') {
3097 dest[index] = JVM_SIGNATURE_DOT;
3098 break;
3099 }
3100 }
3101 }
3102
3103 // Add the semicolon and the null
3104 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3105 dest[dest_index] = '\0';
3106 return dest;
3107 }
3108
3109 ModuleEntry* InstanceKlass::module() const {
3110 if (is_hidden() &&
3111 in_unnamed_package() &&
3112 class_loader_data()->has_class_mirror_holder()) {
3113 // For a non-strong hidden class defined to an unnamed package,
3114 // its (class held) CLD will not have an unnamed module created for it.
3115 // Two choices to find the correct ModuleEntry:
3116 // 1. If hidden class is within a nest, use nest host's module
3117 // 2. Find the unnamed module off from the class loader
3118 // For now option #2 is used since a nest host is not set until
3119 // after the instance class is created in jvm_lookup_define_class().
3120 if (class_loader_data()->is_boot_class_loader_data()) {
3121 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3122 } else {
3123 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3124 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3125 return java_lang_Module::module_entry(module);
3126 }
3127 }
3128
3129 // Class is in a named package
3130 if (!in_unnamed_package()) {
3131 return _package_entry->module();
3132 }
3133
3134 // Class is in an unnamed package, return its loader's unnamed module
3135 return class_loader_data()->unnamed_module();
3136 }
3137
3138 bool InstanceKlass::in_javabase_module() const {
3139 return module()->name() == vmSymbols::java_base();
3140 }
3141
3142 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3143
3144 // ensure java/ packages only loaded by boot or platform builtin loaders
3145 // not needed for shared class since CDS does not archive prohibited classes.
3146 if (!is_shared()) {
3147 check_prohibited_package(name(), loader_data, CHECK);
3148 }
3149
3150 if (is_shared() && _package_entry != nullptr) {
3151 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3152 // we can use the saved package
3153 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3154 return;
3155 } else {
3156 _package_entry = nullptr;
3157 }
3158 }
3159
3160 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3161 // it returns, so we need to decrement it when the current function exits.
3162 TempNewSymbol from_class_name =
3163 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3164
3165 Symbol* pkg_name;
3166 if (pkg_entry != nullptr) {
3167 pkg_name = pkg_entry->name();
3168 } else {
3169 pkg_name = from_class_name;
3170 }
3171
3172 if (pkg_name != nullptr && loader_data != nullptr) {
3173
3174 // Find in class loader's package entry table.
3175 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3176
3177 // If the package name is not found in the loader's package
3178 // entry table, it is an indication that the package has not
3179 // been defined. Consider it defined within the unnamed module.
3180 if (_package_entry == nullptr) {
3181
3182 if (!ModuleEntryTable::javabase_defined()) {
3183 // Before java.base is defined during bootstrapping, define all packages in
3184 // the java.base module. If a non-java.base package is erroneously placed
3185 // in the java.base module it will be caught later when java.base
3186 // is defined by ModuleEntryTable::verify_javabase_packages check.
3187 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3188 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3189 } else {
3190 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3191 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3192 }
3193
3194 // A package should have been successfully created
3195 DEBUG_ONLY(ResourceMark rm(THREAD));
3196 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3197 name()->as_C_string(), loader_data->loader_name_and_id());
3198 }
3199
3200 if (log_is_enabled(Debug, module)) {
3201 ResourceMark rm(THREAD);
3202 ModuleEntry* m = _package_entry->module();
3203 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3204 external_name(),
3205 pkg_name->as_C_string(),
3206 loader_data->loader_name_and_id(),
3207 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3208 }
3209 } else {
3210 ResourceMark rm(THREAD);
3211 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3212 external_name(),
3213 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3214 UNNAMED_MODULE);
3215 }
3216 }
3217
3218 // Function set_classpath_index ensures that for a non-null _package_entry
3219 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3220 // It then sets the classpath_index in the package entry record.
3221 //
3222 // The classpath_index field is used to find the entry on the boot loader class
3223 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3224 // in an unnamed module. It is also used to indicate (for all packages whose
3225 // classes are loaded by the boot loader) that at least one of the package's
3226 // classes has been loaded.
3227 void InstanceKlass::set_classpath_index(s2 path_index) {
3228 if (_package_entry != nullptr) {
3229 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3230 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3231 assert(path_index != -1, "Unexpected classpath_index");
3232 _package_entry->set_classpath_index(path_index);
3233 }
3234 }
3235
3236 // different versions of is_same_class_package
3237
3238 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3239 oop classloader1 = this->class_loader();
3240 PackageEntry* classpkg1 = this->package();
3241 if (class2->is_objArray_klass()) {
3242 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3243 }
3244
3245 oop classloader2;
3246 PackageEntry* classpkg2;
3247 if (class2->is_instance_klass()) {
3248 classloader2 = class2->class_loader();
3249 classpkg2 = class2->package();
3250 } else {
3251 assert(class2->is_typeArray_klass(), "should be type array");
3252 classloader2 = nullptr;
3253 classpkg2 = nullptr;
3254 }
3255
3256 // Same package is determined by comparing class loader
3257 // and package entries. Both must be the same. This rule
3258 // applies even to classes that are defined in the unnamed
3259 // package, they still must have the same class loader.
3260 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3261 return true;
3262 }
3263
3264 return false;
3265 }
3266
3267 // return true if this class and other_class are in the same package. Classloader
3268 // and classname information is enough to determine a class's package
3269 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3270 const Symbol* other_class_name) const {
3271 if (class_loader() != other_class_loader) {
3272 return false;
3273 }
3274 if (name()->fast_compare(other_class_name) == 0) {
3275 return true;
3276 }
3277
3278 {
3279 ResourceMark rm;
3280
3281 bool bad_class_name = false;
3282 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3283 if (bad_class_name) {
3284 return false;
3285 }
3286 // Check that package_from_class_name() returns null, not "", if there is no package.
3287 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3288
3289 const Symbol* const this_package_name =
3290 this->package() != nullptr ? this->package()->name() : nullptr;
3291
3292 if (this_package_name == nullptr || other_pkg == nullptr) {
3293 // One of the two doesn't have a package. Only return true if the other
3294 // one also doesn't have a package.
3295 return this_package_name == other_pkg;
3296 }
3297
3298 // Check if package is identical
3299 return this_package_name->fast_compare(other_pkg) == 0;
3300 }
3301 }
3302
3303 static bool is_prohibited_package_slow(Symbol* class_name) {
3304 // Caller has ResourceMark
3305 int length;
3306 jchar* unicode = class_name->as_unicode(length);
3307 return (length >= 5 &&
3308 unicode[0] == 'j' &&
3309 unicode[1] == 'a' &&
3310 unicode[2] == 'v' &&
3311 unicode[3] == 'a' &&
3312 unicode[4] == '/');
3313 }
3314
3315 // Only boot and platform class loaders can define classes in "java/" packages.
3316 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3317 ClassLoaderData* loader_data,
3318 TRAPS) {
3319 if (!loader_data->is_boot_class_loader_data() &&
3320 !loader_data->is_platform_class_loader_data() &&
3321 class_name != nullptr && class_name->utf8_length() >= 5) {
3322 ResourceMark rm(THREAD);
3323 bool prohibited;
3324 const u1* base = class_name->base();
3325 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3326 prohibited = is_prohibited_package_slow(class_name);
3327 } else {
3328 char* name = class_name->as_C_string();
3329 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3330 }
3331 if (prohibited) {
3332 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3333 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3334 char* name = pkg_name->as_C_string();
3335 const char* class_loader_name = loader_data->loader_name_and_id();
3336 StringUtils::replace_no_expand(name, "/", ".");
3337 const char* msg_text1 = "Class loader (instance of): ";
3338 const char* msg_text2 = " tried to load prohibited package name: ";
3339 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3340 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3341 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3342 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3343 }
3344 }
3345 return;
3346 }
3347
3348 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3349 constantPoolHandle i_cp(THREAD, constants());
3350 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3351 int ioff = iter.inner_class_info_index();
3352 if (ioff != 0) {
3353 // Check to see if the name matches the class we're looking for
3354 // before attempting to find the class.
3355 if (i_cp->klass_name_at_matches(this, ioff)) {
3356 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3357 if (this == inner_klass) {
3358 *ooff = iter.outer_class_info_index();
3359 *noff = iter.inner_name_index();
3360 return true;
3361 }
3362 }
3363 }
3364 }
3365 return false;
3366 }
3367
3368 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3369 InstanceKlass* outer_klass = nullptr;
3370 *inner_is_member = false;
3371 int ooff = 0, noff = 0;
3372 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3373 if (has_inner_classes_attr) {
3374 constantPoolHandle i_cp(THREAD, constants());
3375 if (ooff != 0) {
3376 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3377 if (!ok->is_instance_klass()) {
3378 // If the outer class is not an instance klass then it cannot have
3379 // declared any inner classes.
3380 ResourceMark rm(THREAD);
3381 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3382 Exceptions::fthrow(
3383 THREAD_AND_LOCATION,
3384 vmSymbols::java_lang_IncompatibleClassChangeError(),
3385 "%s and %s disagree on InnerClasses attribute",
3386 ok->external_name(),
3387 external_name());
3388 return nullptr;
3389 }
3390 outer_klass = InstanceKlass::cast(ok);
3391 *inner_is_member = true;
3392 }
3393 if (nullptr == outer_klass) {
3394 // It may be a local class; try for that.
3395 int encl_method_class_idx = enclosing_method_class_index();
3396 if (encl_method_class_idx != 0) {
3397 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3398 outer_klass = InstanceKlass::cast(ok);
3399 *inner_is_member = false;
3400 }
3401 }
3402 }
3403
3404 // If no inner class attribute found for this class.
3405 if (nullptr == outer_klass) return nullptr;
3406
3407 // Throws an exception if outer klass has not declared k as an inner klass
3408 // We need evidence that each klass knows about the other, or else
3409 // the system could allow a spoof of an inner class to gain access rights.
3410 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3411 return outer_klass;
3412 }
3413
3414 u2 InstanceKlass::compute_modifier_flags() const {
3415 u2 access = access_flags().as_unsigned_short();
3416
3417 // But check if it happens to be member class.
3418 InnerClassesIterator iter(this);
3419 for (; !iter.done(); iter.next()) {
3420 int ioff = iter.inner_class_info_index();
3421 // Inner class attribute can be zero, skip it.
3422 // Strange but true: JVM spec. allows null inner class refs.
3423 if (ioff == 0) continue;
3424
3425 // only look at classes that are already loaded
3426 // since we are looking for the flags for our self.
3427 Symbol* inner_name = constants()->klass_name_at(ioff);
3428 if (name() == inner_name) {
3429 // This is really a member class.
3430 access = iter.inner_access_flags();
3431 break;
3432 }
3433 }
3434 // Remember to strip ACC_SUPER bit
3435 return (access & (~JVM_ACC_SUPER));
3436 }
3437
3438 jint InstanceKlass::jvmti_class_status() const {
3439 jint result = 0;
3440
3441 if (is_linked()) {
3442 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3443 }
3444
3445 if (is_initialized()) {
3446 assert(is_linked(), "Class status is not consistent");
3447 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3448 }
3449 if (is_in_error_state()) {
3450 result |= JVMTI_CLASS_STATUS_ERROR;
3451 }
3452 return result;
3453 }
3454
3455 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3456 bool implements_interface; // initialized by method_at_itable_or_null
3457 Method* m = method_at_itable_or_null(holder, index,
3458 implements_interface); // out parameter
3459 if (m != nullptr) {
3460 assert(implements_interface, "sanity");
3461 return m;
3462 } else if (implements_interface) {
3463 // Throw AbstractMethodError since corresponding itable slot is empty.
3464 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3465 } else {
3466 // If the interface isn't implemented by the receiver class,
3467 // the VM should throw IncompatibleClassChangeError.
3468 ResourceMark rm(THREAD);
3469 stringStream ss;
3470 bool same_module = (module() == holder->module());
3471 ss.print("Receiver class %s does not implement "
3472 "the interface %s defining the method to be called "
3473 "(%s%s%s)",
3474 external_name(), holder->external_name(),
3475 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3476 (same_module) ? "" : "; ",
3477 (same_module) ? "" : holder->class_in_module_of_loader());
3478 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3479 }
3480 }
3481
3482 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3483 klassItable itable(this);
3484 for (int i = 0; i < itable.size_offset_table(); i++) {
3485 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3486 if (offset_entry->interface_klass() == holder) {
3487 implements_interface = true;
3488 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3489 Method* m = ime[index].method();
3490 return m;
3491 }
3492 }
3493 implements_interface = false;
3494 return nullptr; // offset entry not found
3495 }
3496
3497 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3498 assert(is_linked(), "required");
3499 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3500 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3501
3502 int vtable_index = Method::invalid_vtable_index;
3503 Symbol* name = intf_method->name();
3504 Symbol* signature = intf_method->signature();
3505
3506 // First check in default method array
3507 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3508 int index = find_method_index(default_methods(),
3509 name, signature,
3510 Klass::OverpassLookupMode::find,
3511 Klass::StaticLookupMode::find,
3512 Klass::PrivateLookupMode::find);
3513 if (index >= 0) {
3514 vtable_index = default_vtable_indices()->at(index);
3515 }
3516 }
3517 if (vtable_index == Method::invalid_vtable_index) {
3518 // get vtable_index for miranda methods
3519 klassVtable vt = vtable();
3520 vtable_index = vt.index_of_miranda(name, signature);
3521 }
3522 return vtable_index;
3523 }
3524
3525 #if INCLUDE_JVMTI
3526 // update default_methods for redefineclasses for methods that are
3527 // not yet in the vtable due to concurrent subclass define and superinterface
3528 // redefinition
3529 // Note: those in the vtable, should have been updated via adjust_method_entries
3530 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3531 // search the default_methods for uses of either obsolete or EMCP methods
3532 if (default_methods() != nullptr) {
3533 for (int index = 0; index < default_methods()->length(); index ++) {
3534 Method* old_method = default_methods()->at(index);
3535 if (old_method == nullptr || !old_method->is_old()) {
3536 continue; // skip uninteresting entries
3537 }
3538 assert(!old_method->is_deleted(), "default methods may not be deleted");
3539 Method* new_method = old_method->get_new_method();
3540 default_methods()->at_put(index, new_method);
3541
3542 if (log_is_enabled(Info, redefine, class, update)) {
3543 ResourceMark rm;
3544 if (!(*trace_name_printed)) {
3545 log_info(redefine, class, update)
3546 ("adjust: klassname=%s default methods from name=%s",
3547 external_name(), old_method->method_holder()->external_name());
3548 *trace_name_printed = true;
3549 }
3550 log_debug(redefine, class, update, vtables)
3551 ("default method update: %s(%s) ",
3552 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3553 }
3554 }
3555 }
3556 }
3557 #endif // INCLUDE_JVMTI
3558
3559 // On-stack replacement stuff
3560 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3561 assert_lock_strong(NMethodState_lock);
3562 #ifndef PRODUCT
3563 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3564 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3565 "redundant OSR recompilation detected. memory leak in CodeCache!");
3566 #endif
3567 // only one compilation can be active
3568 assert(n->is_osr_method(), "wrong kind of nmethod");
3569 n->set_osr_link(osr_nmethods_head());
3570 set_osr_nmethods_head(n);
3571 // Raise the highest osr level if necessary
3572 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3573
3574 // Get rid of the osr methods for the same bci that have lower levels.
3575 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3576 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3577 if (inv != nullptr && inv->is_in_use()) {
3578 inv->make_not_entrant("OSR invalidation of lower levels");
3579 }
3580 }
3581 }
3582
3583 // Remove osr nmethod from the list. Return true if found and removed.
3584 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3585 // This is a short non-blocking critical region, so the no safepoint check is ok.
3586 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3587 assert(n->is_osr_method(), "wrong kind of nmethod");
3588 nmethod* last = nullptr;
3589 nmethod* cur = osr_nmethods_head();
3590 int max_level = CompLevel_none; // Find the max comp level excluding n
3591 Method* m = n->method();
3592 // Search for match
3593 bool found = false;
3594 while(cur != nullptr && cur != n) {
3595 if (m == cur->method()) {
3596 // Find max level before n
3597 max_level = MAX2(max_level, cur->comp_level());
3598 }
3599 last = cur;
3600 cur = cur->osr_link();
3601 }
3602 nmethod* next = nullptr;
3603 if (cur == n) {
3604 found = true;
3605 next = cur->osr_link();
3606 if (last == nullptr) {
3607 // Remove first element
3608 set_osr_nmethods_head(next);
3609 } else {
3610 last->set_osr_link(next);
3611 }
3612 }
3613 n->set_osr_link(nullptr);
3614 cur = next;
3615 while (cur != nullptr) {
3616 // Find max level after n
3617 if (m == cur->method()) {
3618 max_level = MAX2(max_level, cur->comp_level());
3619 }
3620 cur = cur->osr_link();
3621 }
3622 m->set_highest_osr_comp_level(max_level);
3623 return found;
3624 }
3625
3626 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3627 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3628 nmethod* osr = osr_nmethods_head();
3629 int found = 0;
3630 while (osr != nullptr) {
3631 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3632 if (osr->method() == m) {
3633 deopt_scope->mark(osr);
3634 found++;
3635 }
3636 osr = osr->osr_link();
3637 }
3638 return found;
3639 }
3640
3641 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3642 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3643 nmethod* osr = osr_nmethods_head();
3644 nmethod* best = nullptr;
3645 while (osr != nullptr) {
3646 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3647 // There can be a time when a c1 osr method exists but we are waiting
3648 // for a c2 version. When c2 completes its osr nmethod we will trash
3649 // the c1 version and only be able to find the c2 version. However
3650 // while we overflow in the c1 code at back branches we don't want to
3651 // try and switch to the same code as we are already running
3652
3653 if (osr->method() == m &&
3654 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3655 if (match_level) {
3656 if (osr->comp_level() == comp_level) {
3657 // Found a match - return it.
3658 return osr;
3659 }
3660 } else {
3661 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3662 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3663 // Found the best possible - return it.
3664 return osr;
3665 }
3666 best = osr;
3667 }
3668 }
3669 }
3670 osr = osr->osr_link();
3671 }
3672
3673 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3674 if (best != nullptr && best->comp_level() >= comp_level) {
3675 return best;
3676 }
3677 return nullptr;
3678 }
3679
3680 // -----------------------------------------------------------------------------------------------------
3681 // Printing
3682
3683 #define BULLET " - "
3684
3685 static const char* state_names[] = {
3686 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3687 };
3688
3689 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3690 for (int i = 0; i < len; i++) {
3691 intptr_t e = start[i];
3692 st->print("%d : " INTPTR_FORMAT, i, e);
3693 if (MetaspaceObj::is_valid((Metadata*)e)) {
3694 st->print(" ");
3695 ((Metadata*)e)->print_value_on(st);
3696 }
3697 st->cr();
3698 }
3699 }
3700
3701 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3702 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3703 }
3704
3705 const char* InstanceKlass::init_state_name() const {
3706 return state_names[init_state()];
3707 }
3708
3709 const char* InstanceKlass::state2name(ClassState s) {
3710 return state_names[s];
3711 }
3712
3713 void InstanceKlass::print_on(outputStream* st) const {
3714 assert(is_klass(), "must be klass");
3715 Klass::print_on(st);
3716
3717 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3718 st->print(BULLET"klass size: %d", size()); st->cr();
3719 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3720 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3721 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3722 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3723 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3724 st->print(BULLET"sub: ");
3725 Klass* sub = subklass();
3726 int n;
3727 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3728 if (n < MaxSubklassPrintSize) {
3729 sub->print_value_on(st);
3730 st->print(" ");
3731 }
3732 }
3733 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3734 st->cr();
3735
3736 if (is_interface()) {
3737 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3738 if (nof_implementors() == 1) {
3739 st->print_cr(BULLET"implementor: ");
3740 st->print(" ");
3741 implementor()->print_value_on(st);
3742 st->cr();
3743 }
3744 }
3745
3746 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3747 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3748 if (Verbose || WizardMode) {
3749 Array<Method*>* method_array = methods();
3750 for (int i = 0; i < method_array->length(); i++) {
3751 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3752 }
3753 }
3754 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3755 if (default_methods() != nullptr) {
3756 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3757 if (Verbose) {
3758 Array<Method*>* method_array = default_methods();
3759 for (int i = 0; i < method_array->length(); i++) {
3760 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3761 }
3762 }
3763 }
3764 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3765 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3766 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3767
3768 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3769
3770 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3771 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3772
3773 if (secondary_supers() != nullptr) {
3774 if (Verbose) {
3775 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3776 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3777 for (int i = 0; i < _secondary_supers->length(); i++) {
3778 ResourceMark rm; // for external_name()
3779 Klass* secondary_super = _secondary_supers->at(i);
3780 st->print(BULLET"%2d:", i);
3781 if (is_hashed) {
3782 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3783 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3784 st->print(" dist:%02d:", distance);
3785 }
3786 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3787 }
3788 }
3789 }
3790 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3791
3792 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3793 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3794 if (source_debug_extension() != nullptr) {
3795 st->print(BULLET"source debug extension: ");
3796 st->print("%s", source_debug_extension());
3797 st->cr();
3798 }
3799 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3800 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3801 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3802 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3803 {
3804 bool have_pv = false;
3805 // previous versions are linked together through the InstanceKlass
3806 for (InstanceKlass* pv_node = previous_versions();
3807 pv_node != nullptr;
3808 pv_node = pv_node->previous_versions()) {
3809 if (!have_pv)
3810 st->print(BULLET"previous version: ");
3811 have_pv = true;
3812 pv_node->constants()->print_value_on(st);
3813 }
3814 if (have_pv) st->cr();
3815 }
3816
3817 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3818 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3819 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3820 print_on_maybe_null(st, BULLET"record components: ", record_components());
3821 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3822 if (java_mirror() != nullptr) {
3823 st->print(BULLET"java mirror: ");
3824 java_mirror()->print_value_on(st);
3825 st->cr();
3826 } else {
3827 st->print_cr(BULLET"java mirror: null");
3828 }
3829 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3830 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3831 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3832 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3833 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3834
3835 FieldPrinter print_static_field(st);
3836 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3837 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3838 FieldPrinter print_nonstatic_field(st);
3839 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3840 ik->print_nonstatic_fields(&print_nonstatic_field);
3841
3842 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3843 OopMapBlock* map = start_of_nonstatic_oop_maps();
3844 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3845 while (map < end_map) {
3846 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3847 map++;
3848 }
3849 st->cr();
3850 }
3851
3852 void InstanceKlass::print_value_on(outputStream* st) const {
3853 assert(is_klass(), "must be klass");
3854 if (Verbose || WizardMode) access_flags().print_on(st);
3855 name()->print_value_on(st);
3856 }
3857
3858 void FieldPrinter::do_field(fieldDescriptor* fd) {
3859 _st->print(BULLET);
3860 if (_obj == nullptr) {
3861 fd->print_on(_st);
3862 _st->cr();
3863 } else {
3864 fd->print_on_for(_st, _obj);
3865 _st->cr();
3866 }
3867 }
3868
3869
3870 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3871 Klass::oop_print_on(obj, st);
3872
3873 if (this == vmClasses::String_klass()) {
3874 typeArrayOop value = java_lang_String::value(obj);
3875 juint length = java_lang_String::length(obj);
3876 if (value != nullptr &&
3877 value->is_typeArray() &&
3878 length <= (juint) value->length()) {
3879 st->print(BULLET"string: ");
3880 java_lang_String::print(obj, st);
3881 st->cr();
3882 }
3883 }
3884
3885 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3886 FieldPrinter print_field(st, obj);
3887 print_nonstatic_fields(&print_field);
3888
3889 if (this == vmClasses::Class_klass()) {
3890 st->print(BULLET"signature: ");
3891 java_lang_Class::print_signature(obj, st);
3892 st->cr();
3893 Klass* real_klass = java_lang_Class::as_Klass(obj);
3894 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3895 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3896 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3897 }
3898 } else if (this == vmClasses::MethodType_klass()) {
3899 st->print(BULLET"signature: ");
3900 java_lang_invoke_MethodType::print_signature(obj, st);
3901 st->cr();
3902 }
3903 }
3904
3905 #ifndef PRODUCT
3906
3907 bool InstanceKlass::verify_itable_index(int i) {
3908 int method_count = klassItable::method_count_for_interface(this);
3909 assert(i >= 0 && i < method_count, "index out of bounds");
3910 return true;
3911 }
3912
3913 #endif //PRODUCT
3914
3915 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3916 st->print("a ");
3917 name()->print_value_on(st);
3918 obj->print_address_on(st);
3919 if (this == vmClasses::String_klass()
3920 && java_lang_String::value(obj) != nullptr) {
3921 ResourceMark rm;
3922 int len = java_lang_String::length(obj);
3923 int plen = (len < 24 ? len : 12);
3924 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3925 st->print(" = \"%s\"", str);
3926 if (len > plen)
3927 st->print("...[%d]", len);
3928 } else if (this == vmClasses::Class_klass()) {
3929 Klass* k = java_lang_Class::as_Klass(obj);
3930 st->print(" = ");
3931 if (k != nullptr) {
3932 k->print_value_on(st);
3933 } else {
3934 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3935 st->print("%s", tname ? tname : "type?");
3936 }
3937 } else if (this == vmClasses::MethodType_klass()) {
3938 st->print(" = ");
3939 java_lang_invoke_MethodType::print_signature(obj, st);
3940 } else if (java_lang_boxing_object::is_instance(obj)) {
3941 st->print(" = ");
3942 java_lang_boxing_object::print(obj, st);
3943 } else if (this == vmClasses::LambdaForm_klass()) {
3944 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3945 if (vmentry != nullptr) {
3946 st->print(" => ");
3947 vmentry->print_value_on(st);
3948 }
3949 } else if (this == vmClasses::MemberName_klass()) {
3950 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3951 if (vmtarget != nullptr) {
3952 st->print(" = ");
3953 vmtarget->print_value_on(st);
3954 } else {
3955 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3956 oop name = java_lang_invoke_MemberName::name(obj);
3957 if (clazz != nullptr) {
3958 clazz->print_value_on(st);
3959 } else {
3960 st->print("null");
3961 }
3962 st->print(".");
3963 if (name != nullptr) {
3964 name->print_value_on(st);
3965 } else {
3966 st->print("null");
3967 }
3968 }
3969 }
3970 }
3971
3972 const char* InstanceKlass::internal_name() const {
3973 return external_name();
3974 }
3975
3976 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3977 const ModuleEntry* module_entry,
3978 const ClassFileStream* cfs) const {
3979
3980 if (ClassListWriter::is_enabled()) {
3981 ClassListWriter::write(this, cfs);
3982 }
3983
3984 print_class_load_helper(loader_data, module_entry, cfs);
3985 print_class_load_cause_logging();
3986 }
3987
3988 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3989 const ModuleEntry* module_entry,
3990 const ClassFileStream* cfs) const {
3991
3992 if (!log_is_enabled(Info, class, load)) {
3993 return;
3994 }
3995
3996 ResourceMark rm;
3997 LogMessage(class, load) msg;
3998 stringStream info_stream;
3999
4000 // Name and class hierarchy info
4001 info_stream.print("%s", external_name());
4002
4003 // Source
4004 if (cfs != nullptr) {
4005 if (cfs->source() != nullptr) {
4006 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4007 if (module_name != nullptr) {
4008 // When the boot loader created the stream, it didn't know the module name
4009 // yet. Let's format it now.
4010 if (cfs->from_boot_loader_modules_image()) {
4011 info_stream.print(" source: jrt:/%s", module_name);
4012 } else {
4013 info_stream.print(" source: %s", cfs->source());
4014 }
4015 } else {
4016 info_stream.print(" source: %s", cfs->source());
4017 }
4018 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4019 Thread* current = Thread::current();
4020 Klass* caller = current->is_Java_thread() ?
4021 JavaThread::cast(current)->security_get_caller_class(1):
4022 nullptr;
4023 // caller can be null, for example, during a JVMTI VM_Init hook
4024 if (caller != nullptr) {
4025 info_stream.print(" source: instance of %s", caller->external_name());
4026 } else {
4027 // source is unknown
4028 }
4029 } else {
4030 oop class_loader = loader_data->class_loader();
4031 info_stream.print(" source: %s", class_loader->klass()->external_name());
4032 }
4033 } else {
4034 assert(this->is_shared(), "must be");
4035 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4036 info_stream.print(" source: shared objects file (top)");
4037 } else {
4038 info_stream.print(" source: shared objects file");
4039 }
4040 }
4041
4042 info_stream.print(" loader:");
4043 if (is_shared()) {
4044 info_stream.print(" %s", SystemDictionaryShared::loader_type_for_shared_class((Klass*)this));
4045 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4046 info_stream.print(" boot_loader");
4047 } else {
4048 oop class_loader = loader_data->class_loader();
4049 if (class_loader != nullptr) {
4050 info_stream.print(" %s", class_loader->klass()->external_name());
4051 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4052 if (cl_name_and_id != nullptr) {
4053 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4054 }
4055 } else {
4056 info_stream.print(" null");
4057 }
4058 }
4059 msg.info("%s", info_stream.as_string());
4060
4061 if (log_is_enabled(Debug, class, load)) {
4062 stringStream debug_stream;
4063
4064 // Class hierarchy info
4065 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4066 p2i(this), p2i(superklass()));
4067
4068 // Interfaces
4069 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4070 debug_stream.print(" interfaces:");
4071 int length = local_interfaces()->length();
4072 for (int i = 0; i < length; i++) {
4073 debug_stream.print(" " PTR_FORMAT,
4074 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4075 }
4076 }
4077
4078 // Class loader
4079 debug_stream.print(" loader: [");
4080 loader_data->print_value_on(&debug_stream);
4081 debug_stream.print("]");
4082
4083 // Classfile checksum
4084 if (cfs) {
4085 debug_stream.print(" bytes: %d checksum: %08x",
4086 cfs->length(),
4087 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4088 cfs->length()));
4089 }
4090
4091 msg.debug("%s", debug_stream.as_string());
4092 }
4093 }
4094
4095 void InstanceKlass::print_class_load_cause_logging() const {
4096 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4097 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4098 JavaThread* current = JavaThread::current();
4099 ResourceMark rm(current);
4100 const char* name = external_name();
4101
4102 if (LogClassLoadingCauseFor == nullptr ||
4103 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4104 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4105 return;
4106 }
4107
4108 // Log Java stack first
4109 {
4110 LogMessage(class, load, cause) msg;
4111 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4112
4113 info_stream.print_cr("Java stack when loading %s:", name);
4114 current->print_stack_on(&info_stream);
4115 }
4116
4117 // Log native stack second
4118 if (log_cause_native) {
4119 // Log to string first so that lines can be indented
4120 stringStream stack_stream;
4121 char buf[O_BUFLEN];
4122 address lastpc = nullptr;
4123 NativeStackPrinter nsp(current);
4124 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4125 true /* print_source_info */, -1 /* max stack */);
4126
4127 LogMessage(class, load, cause, native) msg;
4128 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4129 info_stream.print_cr("Native stack when loading %s:", name);
4130
4131 // Print each native stack line to the log
4132 int size = (int) stack_stream.size();
4133 char* stack = stack_stream.as_string();
4134 char* stack_end = stack + size;
4135 char* line_start = stack;
4136 for (char* p = stack; p < stack_end; p++) {
4137 if (*p == '\n') {
4138 *p = '\0';
4139 info_stream.print_cr("\t%s", line_start);
4140 line_start = p + 1;
4141 }
4142 }
4143 if (line_start < stack_end) {
4144 info_stream.print_cr("\t%s", line_start);
4145 }
4146 }
4147 }
4148 }
4149
4150 // Verification
4151
4152 class VerifyFieldClosure: public BasicOopIterateClosure {
4153 protected:
4154 template <class T> void do_oop_work(T* p) {
4155 oop obj = RawAccess<>::oop_load(p);
4156 if (!oopDesc::is_oop_or_null(obj)) {
4157 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4158 Universe::print_on(tty);
4159 guarantee(false, "boom");
4160 }
4161 }
4162 public:
4163 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4164 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4165 };
4166
4167 void InstanceKlass::verify_on(outputStream* st) {
4168 #ifndef PRODUCT
4169 // Avoid redundant verifies, this really should be in product.
4170 if (_verify_count == Universe::verify_count()) return;
4171 _verify_count = Universe::verify_count();
4172 #endif
4173
4174 // Verify Klass
4175 Klass::verify_on(st);
4176
4177 // Verify that klass is present in ClassLoaderData
4178 guarantee(class_loader_data()->contains_klass(this),
4179 "this class isn't found in class loader data");
4180
4181 // Verify vtables
4182 if (is_linked()) {
4183 // $$$ This used to be done only for m/s collections. Doing it
4184 // always seemed a valid generalization. (DLD -- 6/00)
4185 vtable().verify(st);
4186 }
4187
4188 // Verify first subklass
4189 if (subklass() != nullptr) {
4190 guarantee(subklass()->is_klass(), "should be klass");
4191 }
4192
4193 // Verify siblings
4194 Klass* super = this->super();
4195 Klass* sib = next_sibling();
4196 if (sib != nullptr) {
4197 if (sib == this) {
4198 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4199 }
4200
4201 guarantee(sib->is_klass(), "should be klass");
4202 guarantee(sib->super() == super, "siblings should have same superklass");
4203 }
4204
4205 // Verify local interfaces
4206 if (local_interfaces()) {
4207 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4208 for (int j = 0; j < local_interfaces->length(); j++) {
4209 InstanceKlass* e = local_interfaces->at(j);
4210 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4211 }
4212 }
4213
4214 // Verify transitive interfaces
4215 if (transitive_interfaces() != nullptr) {
4216 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4217 for (int j = 0; j < transitive_interfaces->length(); j++) {
4218 InstanceKlass* e = transitive_interfaces->at(j);
4219 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4220 }
4221 }
4222
4223 // Verify methods
4224 if (methods() != nullptr) {
4225 Array<Method*>* methods = this->methods();
4226 for (int j = 0; j < methods->length(); j++) {
4227 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4228 }
4229 for (int j = 0; j < methods->length() - 1; j++) {
4230 Method* m1 = methods->at(j);
4231 Method* m2 = methods->at(j + 1);
4232 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4233 }
4234 }
4235
4236 // Verify method ordering
4237 if (method_ordering() != nullptr) {
4238 Array<int>* method_ordering = this->method_ordering();
4239 int length = method_ordering->length();
4240 if (JvmtiExport::can_maintain_original_method_order() ||
4241 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4242 guarantee(length == methods()->length(), "invalid method ordering length");
4243 jlong sum = 0;
4244 for (int j = 0; j < length; j++) {
4245 int original_index = method_ordering->at(j);
4246 guarantee(original_index >= 0, "invalid method ordering index");
4247 guarantee(original_index < length, "invalid method ordering index");
4248 sum += original_index;
4249 }
4250 // Verify sum of indices 0,1,...,length-1
4251 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4252 } else {
4253 guarantee(length == 0, "invalid method ordering length");
4254 }
4255 }
4256
4257 // Verify default methods
4258 if (default_methods() != nullptr) {
4259 Array<Method*>* methods = this->default_methods();
4260 for (int j = 0; j < methods->length(); j++) {
4261 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4262 }
4263 for (int j = 0; j < methods->length() - 1; j++) {
4264 Method* m1 = methods->at(j);
4265 Method* m2 = methods->at(j + 1);
4266 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4267 }
4268 }
4269
4270 // Verify JNI static field identifiers
4271 if (jni_ids() != nullptr) {
4272 jni_ids()->verify(this);
4273 }
4274
4275 // Verify other fields
4276 if (constants() != nullptr) {
4277 guarantee(constants()->is_constantPool(), "should be constant pool");
4278 }
4279 }
4280
4281 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4282 Klass::oop_verify_on(obj, st);
4283 VerifyFieldClosure blk;
4284 obj->oop_iterate(&blk);
4285 }
4286
4287
4288 // JNIid class for jfieldIDs only
4289 // Note to reviewers:
4290 // These JNI functions are just moved over to column 1 and not changed
4291 // in the compressed oops workspace.
4292 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4293 _holder = holder;
4294 _offset = offset;
4295 _next = next;
4296 DEBUG_ONLY(_is_static_field_id = false;)
4297 }
4298
4299
4300 JNIid* JNIid::find(int offset) {
4301 JNIid* current = this;
4302 while (current != nullptr) {
4303 if (current->offset() == offset) return current;
4304 current = current->next();
4305 }
4306 return nullptr;
4307 }
4308
4309 void JNIid::deallocate(JNIid* current) {
4310 while (current != nullptr) {
4311 JNIid* next = current->next();
4312 delete current;
4313 current = next;
4314 }
4315 }
4316
4317
4318 void JNIid::verify(Klass* holder) {
4319 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4320 int end_field_offset;
4321 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4322
4323 JNIid* current = this;
4324 while (current != nullptr) {
4325 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4326 #ifdef ASSERT
4327 int o = current->offset();
4328 if (current->is_static_field_id()) {
4329 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4330 }
4331 #endif
4332 current = current->next();
4333 }
4334 }
4335
4336 void InstanceKlass::set_init_state(ClassState state) {
4337 #ifdef ASSERT
4338 bool good_state = is_shared() ? (_init_state <= state)
4339 : (_init_state < state);
4340 assert(good_state || state == allocated, "illegal state transition");
4341 #endif
4342 assert(_init_thread == nullptr, "should be cleared before state change");
4343 Atomic::release_store(&_init_state, state);
4344 }
4345
4346 #if INCLUDE_JVMTI
4347
4348 // RedefineClasses() support for previous versions
4349
4350 // Globally, there is at least one previous version of a class to walk
4351 // during class unloading, which is saved because old methods in the class
4352 // are still running. Otherwise the previous version list is cleaned up.
4353 bool InstanceKlass::_should_clean_previous_versions = false;
4354
4355 // Returns true if there are previous versions of a class for class
4356 // unloading only. Also resets the flag to false. purge_previous_version
4357 // will set the flag to true if there are any left, i.e., if there's any
4358 // work to do for next time. This is to avoid the expensive code cache
4359 // walk in CLDG::clean_deallocate_lists().
4360 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4361 bool ret = _should_clean_previous_versions;
4362 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4363 ret ? "true" : "false");
4364 _should_clean_previous_versions = false;
4365 return ret;
4366 }
4367
4368 // This nulls out jmethodIDs for all methods in 'klass'
4369 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4370 // during class unloading.
4371 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4372 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4373 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4374 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4375 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4376 Array<Method*>* method_refs = klass->methods();
4377 for (int k = 0; k < method_refs->length(); k++) {
4378 Method* method = method_refs->at(k);
4379 if (method != nullptr && method->is_obsolete()) {
4380 method->clear_jmethod_id();
4381 }
4382 }
4383 }
4384
4385 // Purge previous versions before adding new previous versions of the class and
4386 // during class unloading.
4387 void InstanceKlass::purge_previous_version_list() {
4388 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4389 assert(has_been_redefined(), "Should only be called for main class");
4390
4391 // Quick exit.
4392 if (previous_versions() == nullptr) {
4393 return;
4394 }
4395
4396 // This klass has previous versions so see what we can cleanup
4397 // while it is safe to do so.
4398
4399 int deleted_count = 0; // leave debugging breadcrumbs
4400 int live_count = 0;
4401 ClassLoaderData* loader_data = class_loader_data();
4402 assert(loader_data != nullptr, "should never be null");
4403
4404 ResourceMark rm;
4405 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4406
4407 // previous versions are linked together through the InstanceKlass
4408 InstanceKlass* pv_node = previous_versions();
4409 InstanceKlass* last = this;
4410 int version = 0;
4411
4412 // check the previous versions list
4413 for (; pv_node != nullptr; ) {
4414
4415 ConstantPool* pvcp = pv_node->constants();
4416 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4417
4418 if (!pvcp->on_stack()) {
4419 // If the constant pool isn't on stack, none of the methods
4420 // are executing. Unlink this previous_version.
4421 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4422 // so will be deallocated during the next phase of class unloading.
4423 log_trace(redefine, class, iklass, purge)
4424 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4425 // Unlink from previous version list.
4426 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4427 InstanceKlass* next = pv_node->previous_versions();
4428 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4429 pv_node->link_previous_versions(nullptr); // point next to null
4430 last->link_previous_versions(next);
4431 // Delete this node directly. Nothing is referring to it and we don't
4432 // want it to increase the counter for metadata to delete in CLDG.
4433 MetadataFactory::free_metadata(loader_data, pv_node);
4434 pv_node = next;
4435 deleted_count++;
4436 version++;
4437 continue;
4438 } else {
4439 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4440 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4441 live_count++;
4442 if (pvcp->is_shared()) {
4443 // Shared previous versions can never be removed so no cleaning is needed.
4444 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4445 } else {
4446 // Previous version alive, set that clean is needed for next time.
4447 _should_clean_previous_versions = true;
4448 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4449 }
4450 }
4451
4452 // next previous version
4453 last = pv_node;
4454 pv_node = pv_node->previous_versions();
4455 version++;
4456 }
4457 log_trace(redefine, class, iklass, purge)
4458 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4459 }
4460
4461 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4462 int emcp_method_count) {
4463 int obsolete_method_count = old_methods->length() - emcp_method_count;
4464
4465 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4466 _previous_versions != nullptr) {
4467 // We have a mix of obsolete and EMCP methods so we have to
4468 // clear out any matching EMCP method entries the hard way.
4469 int local_count = 0;
4470 for (int i = 0; i < old_methods->length(); i++) {
4471 Method* old_method = old_methods->at(i);
4472 if (old_method->is_obsolete()) {
4473 // only obsolete methods are interesting
4474 Symbol* m_name = old_method->name();
4475 Symbol* m_signature = old_method->signature();
4476
4477 // previous versions are linked together through the InstanceKlass
4478 int j = 0;
4479 for (InstanceKlass* prev_version = _previous_versions;
4480 prev_version != nullptr;
4481 prev_version = prev_version->previous_versions(), j++) {
4482
4483 Array<Method*>* method_refs = prev_version->methods();
4484 for (int k = 0; k < method_refs->length(); k++) {
4485 Method* method = method_refs->at(k);
4486
4487 if (!method->is_obsolete() &&
4488 method->name() == m_name &&
4489 method->signature() == m_signature) {
4490 // The current RedefineClasses() call has made all EMCP
4491 // versions of this method obsolete so mark it as obsolete
4492 log_trace(redefine, class, iklass, add)
4493 ("%s(%s): flush obsolete method @%d in version @%d",
4494 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4495
4496 method->set_is_obsolete();
4497 break;
4498 }
4499 }
4500
4501 // The previous loop may not find a matching EMCP method, but
4502 // that doesn't mean that we can optimize and not go any
4503 // further back in the PreviousVersion generations. The EMCP
4504 // method for this generation could have already been made obsolete,
4505 // but there still may be an older EMCP method that has not
4506 // been made obsolete.
4507 }
4508
4509 if (++local_count >= obsolete_method_count) {
4510 // no more obsolete methods so bail out now
4511 break;
4512 }
4513 }
4514 }
4515 }
4516 }
4517
4518 // Save the scratch_class as the previous version if any of the methods are running.
4519 // The previous_versions are used to set breakpoints in EMCP methods and they are
4520 // also used to clean MethodData links to redefined methods that are no longer running.
4521 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4522 int emcp_method_count) {
4523 assert(Thread::current()->is_VM_thread(),
4524 "only VMThread can add previous versions");
4525
4526 ResourceMark rm;
4527 log_trace(redefine, class, iklass, add)
4528 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4529
4530 // Clean out old previous versions for this class
4531 purge_previous_version_list();
4532
4533 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4534 // a previous redefinition may be made obsolete by this redefinition.
4535 Array<Method*>* old_methods = scratch_class->methods();
4536 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4537
4538 // If the constant pool for this previous version of the class
4539 // is not marked as being on the stack, then none of the methods
4540 // in this previous version of the class are on the stack so
4541 // we don't need to add this as a previous version.
4542 ConstantPool* cp_ref = scratch_class->constants();
4543 if (!cp_ref->on_stack()) {
4544 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4545 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4546 return;
4547 }
4548
4549 // Add previous version if any methods are still running or if this is
4550 // a shared class which should never be removed.
4551 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4552 scratch_class->link_previous_versions(previous_versions());
4553 link_previous_versions(scratch_class);
4554 if (cp_ref->is_shared()) {
4555 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4556 } else {
4557 // We only set clean_previous_versions flag for processing during class
4558 // unloading for non-shared classes.
4559 _should_clean_previous_versions = true;
4560 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4561 }
4562 } // end add_previous_version()
4563
4564 #endif // INCLUDE_JVMTI
4565
4566 Method* InstanceKlass::method_with_idnum(int idnum) {
4567 Method* m = nullptr;
4568 if (idnum < methods()->length()) {
4569 m = methods()->at(idnum);
4570 }
4571 if (m == nullptr || m->method_idnum() != idnum) {
4572 for (int index = 0; index < methods()->length(); ++index) {
4573 m = methods()->at(index);
4574 if (m->method_idnum() == idnum) {
4575 return m;
4576 }
4577 }
4578 // None found, return null for the caller to handle.
4579 return nullptr;
4580 }
4581 return m;
4582 }
4583
4584
4585 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4586 if (idnum >= methods()->length()) {
4587 return nullptr;
4588 }
4589 Method* m = methods()->at(idnum);
4590 if (m != nullptr && m->orig_method_idnum() == idnum) {
4591 return m;
4592 }
4593 // Obsolete method idnum does not match the original idnum
4594 for (int index = 0; index < methods()->length(); ++index) {
4595 m = methods()->at(index);
4596 if (m->orig_method_idnum() == idnum) {
4597 return m;
4598 }
4599 }
4600 // None found, return null for the caller to handle.
4601 return nullptr;
4602 }
4603
4604
4605 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4606 InstanceKlass* holder = get_klass_version(version);
4607 if (holder == nullptr) {
4608 return nullptr; // The version of klass is gone, no method is found
4609 }
4610 Method* method = holder->method_with_orig_idnum(idnum);
4611 return method;
4612 }
4613
4614 #if INCLUDE_JVMTI
4615 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4616 return _cached_class_file;
4617 }
4618
4619 jint InstanceKlass::get_cached_class_file_len() {
4620 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4621 }
4622
4623 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4624 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4625 }
4626 #endif
4627
4628 // Make a step iterating over the class hierarchy under the root class.
4629 // Skips subclasses if requested.
4630 void ClassHierarchyIterator::next() {
4631 assert(_current != nullptr, "required");
4632 if (_visit_subclasses && _current->subklass() != nullptr) {
4633 _current = _current->subklass();
4634 return; // visit next subclass
4635 }
4636 _visit_subclasses = true; // reset
4637 while (_current->next_sibling() == nullptr && _current != _root) {
4638 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4639 }
4640 if (_current == _root) {
4641 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4642 _current = nullptr;
4643 return;
4644 }
4645 _current = _current->next_sibling();
4646 return; // visit next sibling subclass
4647 }