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