1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotClassInitializer.hpp"
26 #include "cds/archiveUtils.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/cdsEnumKlass.hpp"
29 #include "cds/classListWriter.hpp"
30 #include "cds/heapShared.hpp"
31 #include "cds/metaspaceShared.hpp"
32 #include "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeHistogram.hpp"
49 #include "interpreter/bytecodeStream.hpp"
50 #include "interpreter/oopMapCache.hpp"
51 #include "interpreter/rewriter.hpp"
52 #include "jvm.h"
53 #include "jvmtifiles/jvmti.h"
54 #include "logging/log.hpp"
55 #include "klass.inline.hpp"
56 #include "logging/logMessage.hpp"
57 #include "logging/logStream.hpp"
58 #include "memory/allocation.inline.hpp"
59 #include "memory/iterator.inline.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceClosure.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "memory/universe.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/constantPool.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/runtimeUpcalls.hpp"
93 #include "runtime/synchronizer.hpp"
94 #include "runtime/threads.hpp"
95 #include "services/classLoadingService.hpp"
96 #include "services/finalizerService.hpp"
97 #include "services/threadService.hpp"
98 #include "utilities/dtrace.hpp"
99 #include "utilities/events.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/nativeStackPrinter.hpp"
102 #include "utilities/stringUtils.hpp"
103 #ifdef COMPILER1
104 #include "c1/c1_Compiler.hpp"
105 #endif
106 #if INCLUDE_JFR
107 #include "jfr/jfrEvents.hpp"
108 #endif
109
110 #ifdef DTRACE_ENABLED
111
112
113 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
114 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
115 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
116 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
117 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
118 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
119 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
120 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
121 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
122 { \
123 char* data = nullptr; \
124 int len = 0; \
125 Symbol* clss_name = name(); \
126 if (clss_name != nullptr) { \
127 data = (char*)clss_name->bytes(); \
128 len = clss_name->utf8_length(); \
129 } \
130 HOTSPOT_CLASS_INITIALIZATION_##type( \
131 data, len, (void*)class_loader(), thread_type); \
132 }
133
134 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
135 { \
136 char* data = nullptr; \
137 int len = 0; \
138 Symbol* clss_name = name(); \
139 if (clss_name != nullptr) { \
140 data = (char*)clss_name->bytes(); \
141 len = clss_name->utf8_length(); \
142 } \
143 HOTSPOT_CLASS_INITIALIZATION_##type( \
144 data, len, (void*)class_loader(), thread_type, wait); \
145 }
146
147 #else // ndef DTRACE_ENABLED
148
149 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
150 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
151
152 #endif // ndef DTRACE_ENABLED
153
154 bool InstanceKlass::_finalization_enabled = true;
155
156 static inline bool is_class_loader(const Symbol* class_name,
157 const ClassFileParser& parser) {
158 assert(class_name != nullptr, "invariant");
159
160 if (class_name == vmSymbols::java_lang_ClassLoader()) {
161 return true;
162 }
163
164 if (vmClasses::ClassLoader_klass_loaded()) {
165 const Klass* const super_klass = parser.super_klass();
166 if (super_klass != nullptr) {
167 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
168 return true;
169 }
170 }
171 }
172 return false;
173 }
174
175 static inline bool is_stack_chunk_class(const Symbol* class_name,
176 const ClassLoaderData* loader_data) {
177 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
178 loader_data->is_the_null_class_loader_data());
179 }
180
181 // private: called to verify that k is a static member of this nest.
182 // We know that k is an instance class in the same package and hence the
183 // same classloader.
184 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
185 assert(!is_hidden(), "unexpected hidden class");
186 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
187 if (log_is_enabled(Trace, class, nestmates)) {
188 ResourceMark rm(current);
189 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
190 k->external_name(), this->external_name());
191 }
192 return false;
193 }
194
195 if (log_is_enabled(Trace, class, nestmates)) {
196 ResourceMark rm(current);
197 log_trace(class, nestmates)("Checking nest membership of %s in %s",
198 k->external_name(), this->external_name());
199 }
200
201 // Check for the named class in _nest_members.
202 // We don't resolve, or load, any classes.
203 for (int i = 0; i < _nest_members->length(); i++) {
204 int cp_index = _nest_members->at(i);
205 Symbol* name = _constants->klass_name_at(cp_index);
206 if (name == k->name()) {
207 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
208 return true;
209 }
210 }
211 log_trace(class, nestmates)("- class is NOT a nest member!");
212 return false;
213 }
214
215 // Called to verify that k is a permitted subclass of this class.
216 // The incoming stringStream is used to format the messages for error logging and for the caller
217 // to use for exception throwing.
218 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
219 Thread* current = Thread::current();
220 assert(k != nullptr, "sanity check");
221 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
222 "unexpected empty _permitted_subclasses array");
223
224 if (log_is_enabled(Trace, class, sealed)) {
225 ResourceMark rm(current);
226 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
227 k->external_name(), this->external_name());
228 }
229
230 // Check that the class and its super are in the same module.
231 if (k->module() != this->module()) {
232 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
233 "and sealed class %s is in module '%s' with loader %s",
234 k->external_name(),
235 k->module()->name_as_C_string(),
236 k->module()->loader_data()->loader_name_and_id(),
237 this->external_name(),
238 this->module()->name_as_C_string(),
239 this->module()->loader_data()->loader_name_and_id());
240 log_trace(class, sealed)(" - %s", ss.as_string());
241 return false;
242 }
243
244 if (!k->is_public() && !is_same_class_package(k)) {
245 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
246 "and sealed class %s is in package '%s' with classloader %s",
247 k->external_name(),
248 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
249 k->module()->loader_data()->loader_name_and_id(),
250 this->external_name(),
251 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
252 this->module()->loader_data()->loader_name_and_id());
253 log_trace(class, sealed)(" - %s", ss.as_string());
254 return false;
255 }
256
257 for (int i = 0; i < _permitted_subclasses->length(); i++) {
258 int cp_index = _permitted_subclasses->at(i);
259 Symbol* name = _constants->klass_name_at(cp_index);
260 if (name == k->name()) {
261 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
262 return true;
263 }
264 }
265
266 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
267 k->external_name(), this->external_name());
268 log_trace(class, sealed)(" - %s", ss.as_string());
269 return false;
270 }
271
272 // Return nest-host class, resolving, validating and saving it if needed.
273 // In cases where this is called from a thread that cannot do classloading
274 // (such as a native JIT thread) then we simply return null, which in turn
275 // causes the access check to return false. Such code will retry the access
276 // from a more suitable environment later. Otherwise the _nest_host is always
277 // set once this method returns.
278 // Any errors from nest-host resolution must be preserved so they can be queried
279 // from higher-level access checking code, and reported as part of access checking
280 // exceptions.
281 // VirtualMachineErrors are propagated with a null return.
282 // Under any conditions where the _nest_host can be set to non-null the resulting
283 // value of it and, if applicable, the nest host resolution/validation error,
284 // are idempotent.
285 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
286 InstanceKlass* nest_host_k = _nest_host;
287 if (nest_host_k != nullptr) {
288 return nest_host_k;
289 }
290
291 ResourceMark rm(THREAD);
292
293 // need to resolve and save our nest-host class.
294 if (_nest_host_index != 0) { // we have a real nest_host
295 // Before trying to resolve check if we're in a suitable context
296 bool can_resolve = THREAD->can_call_java();
297 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
298 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
299 this->external_name());
300 return nullptr; // sentinel to say "try again from a different context"
301 }
302
303 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
304 this->external_name(),
305 _constants->klass_name_at(_nest_host_index)->as_C_string());
306
307 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
308 if (HAS_PENDING_EXCEPTION) {
309 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
310 return nullptr; // propagate VMEs
311 }
312 stringStream ss;
313 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
314 ss.print("Nest host resolution of %s with host %s failed: ",
315 this->external_name(), target_host_class);
316 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
317 const char* msg = ss.as_string(true /* on C-heap */);
318 constantPoolHandle cph(THREAD, constants());
319 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
320 CLEAR_PENDING_EXCEPTION;
321
322 log_trace(class, nestmates)("%s", msg);
323 } else {
324 // A valid nest-host is an instance class in the current package that lists this
325 // class as a nest member. If any of these conditions are not met the class is
326 // its own nest-host.
327 const char* error = nullptr;
328
329 // JVMS 5.4.4 indicates package check comes first
330 if (is_same_class_package(k)) {
331 // Now check actual membership. We can't be a member if our "host" is
332 // not an instance class.
333 if (k->is_instance_klass()) {
334 nest_host_k = InstanceKlass::cast(k);
335 bool is_member = nest_host_k->has_nest_member(THREAD, this);
336 if (is_member) {
337 _nest_host = nest_host_k; // save resolved nest-host value
338
339 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
340 this->external_name(), k->external_name());
341 return nest_host_k;
342 } else {
343 error = "current type is not listed as a nest member";
344 }
345 } else {
346 error = "host is not an instance class";
347 }
348 } else {
349 error = "types are in different packages";
350 }
351
352 // something went wrong, so record what and log it
353 {
354 stringStream ss;
355 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
356 this->external_name(),
357 this->class_loader_data()->loader_name_and_id(),
358 k->external_name(),
359 k->class_loader_data()->loader_name_and_id(),
360 error);
361 const char* msg = ss.as_string(true /* on C-heap */);
362 constantPoolHandle cph(THREAD, constants());
363 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
364 log_trace(class, nestmates)("%s", msg);
365 }
366 }
367 } else {
368 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
369 this->external_name());
370 }
371
372 // Either not in an explicit nest, or else an error occurred, so
373 // the nest-host is set to `this`. Any thread that sees this assignment
374 // will also see any setting of nest_host_error(), if applicable.
375 return (_nest_host = this);
376 }
377
378 // Dynamic nest member support: set this class's nest host to the given class.
379 // This occurs as part of the class definition, as soon as the instanceKlass
380 // has been created and doesn't require further resolution. The code:
381 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
382 // results in:
383 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
384 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
385 // We also know the "host" is a valid nest-host in the same package so we can
386 // assert some of those facts.
387 void InstanceKlass::set_nest_host(InstanceKlass* host) {
388 assert(is_hidden(), "must be a hidden class");
389 assert(host != nullptr, "null nest host specified");
390 assert(_nest_host == nullptr, "current class has resolved nest-host");
391 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
392 nest_host_error());
393 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
394 (host->_nest_host == host), "proposed host is not a valid nest-host");
395 // Can't assert this as package is not set yet:
396 // assert(is_same_class_package(host), "proposed host is in wrong package");
397
398 if (log_is_enabled(Trace, class, nestmates)) {
399 ResourceMark rm;
400 const char* msg = "";
401 // a hidden class does not expect a statically defined nest-host
402 if (_nest_host_index > 0) {
403 msg = "(the NestHost attribute in the current class is ignored)";
404 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
405 msg = "(the NestMembers attribute in the current class is ignored)";
406 }
407 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
408 this->external_name(),
409 host->external_name(),
410 msg);
411 }
412 // set dynamic nest host
413 _nest_host = host;
414 // Record dependency to keep nest host from being unloaded before this class.
415 ClassLoaderData* this_key = class_loader_data();
416 assert(this_key != nullptr, "sanity");
417 this_key->record_dependency(host);
418 }
419
420 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
421 // or we are k's nest_host - all of which is covered by comparing the two
422 // resolved_nest_hosts.
423 // Any exceptions (i.e. VMEs) are propagated.
424 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
425
426 assert(this != k, "this should be handled by higher-level code");
427
428 // Per JVMS 5.4.4 we first resolve and validate the current class, then
429 // the target class k.
430
431 InstanceKlass* cur_host = nest_host(CHECK_false);
432 if (cur_host == nullptr) {
433 return false;
434 }
435
436 Klass* k_nest_host = k->nest_host(CHECK_false);
437 if (k_nest_host == nullptr) {
438 return false;
439 }
440
441 bool access = (cur_host == k_nest_host);
442
443 ResourceMark rm(THREAD);
444 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
445 this->external_name(),
446 access ? "" : "NOT ",
447 k->external_name());
448 return access;
449 }
450
451 const char* InstanceKlass::nest_host_error() {
452 if (_nest_host_index == 0) {
453 return nullptr;
454 } else {
455 constantPoolHandle cph(Thread::current(), constants());
456 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
457 }
458 }
459
460 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
461 bool use_class_space, TRAPS) throw() {
462 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
463 }
464
465 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
466 const int size = InstanceKlass::size(parser.vtable_size(),
467 parser.itable_size(),
468 nonstatic_oop_map_size(parser.total_oop_map_count()),
469 parser.is_interface());
470
471 const Symbol* const class_name = parser.class_name();
472 assert(class_name != nullptr, "invariant");
473 ClassLoaderData* loader_data = parser.loader_data();
474 assert(loader_data != nullptr, "invariant");
475
476 InstanceKlass* ik;
477 const bool use_class_space = parser.klass_needs_narrow_id();
478
479 // Allocation
480 if (parser.is_instance_ref_klass()) {
481 // java.lang.ref.Reference
482 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
483 } else if (class_name == vmSymbols::java_lang_Class()) {
484 // mirror - java.lang.Class
485 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
486 } else if (is_stack_chunk_class(class_name, loader_data)) {
487 // stack chunk
488 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
489 } else if (is_class_loader(class_name, parser)) {
490 // class loader - java.lang.ClassLoader
491 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
492 } else {
493 // normal
494 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
495 }
496
497 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
498 assert(CompressedKlassPointers::is_encodable(ik),
499 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
500 }
501
502 // Check for pending exception before adding to the loader data and incrementing
503 // class count. Can get OOM here.
504 if (HAS_PENDING_EXCEPTION) {
505 return nullptr;
506 }
507
508 return ik;
509 }
510
511
512 // copy method ordering from resource area to Metaspace
513 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
514 if (m != nullptr) {
515 // allocate a new array and copy contents (memcpy?)
516 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
517 for (int i = 0; i < m->length(); i++) {
518 _method_ordering->at_put(i, m->at(i));
519 }
520 } else {
521 _method_ordering = Universe::the_empty_int_array();
522 }
523 }
524
525 // create a new array of vtable_indices for default methods
526 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
527 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
528 assert(default_vtable_indices() == nullptr, "only create once");
529 set_default_vtable_indices(vtable_indices);
530 return vtable_indices;
531 }
532
533
534 InstanceKlass::InstanceKlass() {
535 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
536 }
537
538 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
539 Klass(kind),
540 _nest_members(nullptr),
541 _nest_host(nullptr),
542 _permitted_subclasses(nullptr),
543 _record_components(nullptr),
544 _static_field_size(parser.static_field_size()),
545 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
546 _itable_len(parser.itable_size()),
547 _nest_host_index(0),
548 _init_state(allocated),
549 _reference_type(reference_type),
550 _init_thread(nullptr)
551 {
552 set_vtable_length(parser.vtable_size());
553 set_access_flags(parser.access_flags());
554 if (parser.is_hidden()) set_is_hidden();
555 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
556 false));
557
558 assert(nullptr == _methods, "underlying memory not zeroed?");
559 assert(is_instance_klass(), "is layout incorrect?");
560 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
561 }
562
563 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
564 Array<Method*>* methods) {
565 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
566 !methods->is_shared()) {
567 for (int i = 0; i < methods->length(); i++) {
568 Method* method = methods->at(i);
569 if (method == nullptr) continue; // maybe null if error processing
570 // Only want to delete methods that are not executing for RedefineClasses.
571 // The previous version will point to them so they're not totally dangling
572 assert (!method->on_stack(), "shouldn't be called with methods on stack");
573 MetadataFactory::free_metadata(loader_data, method);
574 }
575 MetadataFactory::free_array<Method*>(loader_data, methods);
576 }
577 }
578
579 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
580 const Klass* super_klass,
581 Array<InstanceKlass*>* local_interfaces,
582 Array<InstanceKlass*>* transitive_interfaces) {
583 // Only deallocate transitive interfaces if not empty, same as super class
584 // or same as local interfaces. See code in parseClassFile.
585 Array<InstanceKlass*>* ti = transitive_interfaces;
586 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
587 // check that the interfaces don't come from super class
588 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
589 InstanceKlass::cast(super_klass)->transitive_interfaces();
590 if (ti != sti && ti != nullptr && !ti->is_shared()) {
591 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
592 }
593 }
594
595 // local interfaces can be empty
596 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
597 local_interfaces != nullptr && !local_interfaces->is_shared()) {
598 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
599 }
600 }
601
602 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
603 Array<RecordComponent*>* record_components) {
604 if (record_components != nullptr && !record_components->is_shared()) {
605 for (int i = 0; i < record_components->length(); i++) {
606 RecordComponent* record_component = record_components->at(i);
607 MetadataFactory::free_metadata(loader_data, record_component);
608 }
609 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
610 }
611 }
612
613 // This function deallocates the metadata and C heap pointers that the
614 // InstanceKlass points to.
615 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
616 // Orphan the mirror first, CMS thinks it's still live.
617 if (java_mirror() != nullptr) {
618 java_lang_Class::set_klass(java_mirror(), nullptr);
619 }
620
621 // Also remove mirror from handles
622 loader_data->remove_handle(_java_mirror);
623
624 // Need to take this class off the class loader data list.
625 loader_data->remove_class(this);
626
627 // The array_klass for this class is created later, after error handling.
628 // For class redefinition, we keep the original class so this scratch class
629 // doesn't have an array class. Either way, assert that there is nothing
630 // to deallocate.
631 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
632
633 // Release C heap allocated data that this points to, which includes
634 // reference counting symbol names.
635 // Can't release the constant pool or MethodData C heap data here because the constant
636 // pool can be deallocated separately from the InstanceKlass for default methods and
637 // redefine classes. MethodData can also be released separately.
638 release_C_heap_structures(/* release_sub_metadata */ false);
639
640 deallocate_methods(loader_data, methods());
641 set_methods(nullptr);
642
643 deallocate_record_components(loader_data, record_components());
644 set_record_components(nullptr);
645
646 if (method_ordering() != nullptr &&
647 method_ordering() != Universe::the_empty_int_array() &&
648 !method_ordering()->is_shared()) {
649 MetadataFactory::free_array<int>(loader_data, method_ordering());
650 }
651 set_method_ordering(nullptr);
652
653 // default methods can be empty
654 if (default_methods() != nullptr &&
655 default_methods() != Universe::the_empty_method_array() &&
656 !default_methods()->is_shared()) {
657 MetadataFactory::free_array<Method*>(loader_data, default_methods());
658 }
659 // Do NOT deallocate the default methods, they are owned by superinterfaces.
660 set_default_methods(nullptr);
661
662 // default methods vtable indices can be empty
663 if (default_vtable_indices() != nullptr &&
664 !default_vtable_indices()->is_shared()) {
665 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
666 }
667 set_default_vtable_indices(nullptr);
668
669
670 // This array is in Klass, but remove it with the InstanceKlass since
671 // this place would be the only caller and it can share memory with transitive
672 // interfaces.
673 if (secondary_supers() != nullptr &&
674 secondary_supers() != Universe::the_empty_klass_array() &&
675 // see comments in compute_secondary_supers about the following cast
676 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
677 !secondary_supers()->is_shared()) {
678 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
679 }
680 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
681
682 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
683 set_transitive_interfaces(nullptr);
684 set_local_interfaces(nullptr);
685
686 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
687 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
688 }
689 set_fieldinfo_stream(nullptr);
690
691 if (fields_status() != nullptr && !fields_status()->is_shared()) {
692 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
693 }
694 set_fields_status(nullptr);
695
696 // If a method from a redefined class is using this constant pool, don't
697 // delete it, yet. The new class's previous version will point to this.
698 if (constants() != nullptr) {
699 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
700 if (!constants()->is_shared()) {
701 MetadataFactory::free_metadata(loader_data, constants());
702 }
703 // Delete any cached resolution errors for the constant pool
704 SystemDictionary::delete_resolution_error(constants());
705
706 set_constants(nullptr);
707 }
708
709 if (inner_classes() != nullptr &&
710 inner_classes() != Universe::the_empty_short_array() &&
711 !inner_classes()->is_shared()) {
712 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
713 }
714 set_inner_classes(nullptr);
715
716 if (nest_members() != nullptr &&
717 nest_members() != Universe::the_empty_short_array() &&
718 !nest_members()->is_shared()) {
719 MetadataFactory::free_array<jushort>(loader_data, nest_members());
720 }
721 set_nest_members(nullptr);
722
723 if (permitted_subclasses() != nullptr &&
724 permitted_subclasses() != Universe::the_empty_short_array() &&
725 !permitted_subclasses()->is_shared()) {
726 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
727 }
728 set_permitted_subclasses(nullptr);
729
730 // We should deallocate the Annotations instance if it's not in shared spaces.
731 if (annotations() != nullptr && !annotations()->is_shared()) {
732 MetadataFactory::free_metadata(loader_data, annotations());
733 }
734 set_annotations(nullptr);
735
736 SystemDictionaryShared::handle_class_unloading(this);
737
738 #if INCLUDE_CDS_JAVA_HEAP
739 if (CDSConfig::is_dumping_heap()) {
740 HeapShared::remove_scratch_objects(this);
741 }
742 #endif
743 }
744
745 bool InstanceKlass::is_record() const {
746 return _record_components != nullptr &&
747 is_final() &&
748 java_super() == vmClasses::Record_klass();
749 }
750
751 bool InstanceKlass::is_sealed() const {
752 return _permitted_subclasses != nullptr &&
753 _permitted_subclasses != Universe::the_empty_short_array();
754 }
755
756 // JLS 8.9: An enum class is either implicitly final and derives
757 // from java.lang.Enum, or else is implicitly sealed to its
758 // anonymous subclasses. This query detects both kinds.
759 // It does not validate the finality or
760 // sealing conditions: it merely checks for a super of Enum.
761 // This is sufficient for recognizing well-formed enums.
762 bool InstanceKlass::is_enum_subclass() const {
763 InstanceKlass* s = java_super();
764 return (s == vmClasses::Enum_klass() ||
765 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
766 }
767
768 bool InstanceKlass::should_be_initialized() const {
769 return !is_initialized();
770 }
771
772 klassItable InstanceKlass::itable() const {
773 return klassItable(const_cast<InstanceKlass*>(this));
774 }
775
776 // JVMTI spec thinks there are signers and protection domain in the
777 // instanceKlass. These accessors pretend these fields are there.
778 // The hprof specification also thinks these fields are in InstanceKlass.
779 oop InstanceKlass::protection_domain() const {
780 // return the protection_domain from the mirror
781 return java_lang_Class::protection_domain(java_mirror());
782 }
783
784 objArrayOop InstanceKlass::signers() const {
785 // return the signers from the mirror
786 return java_lang_Class::signers(java_mirror());
787 }
788
789 oop InstanceKlass::init_lock() const {
790 // return the init lock from the mirror
791 oop lock = java_lang_Class::init_lock(java_mirror());
792 // Prevent reordering with any access of initialization state
793 OrderAccess::loadload();
794 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
795 "only fully initialized state can have a null lock");
796 return lock;
797 }
798
799 // Set the initialization lock to null so the object can be GC'ed. Any racing
800 // threads to get this lock will see a null lock and will not lock.
801 // That's okay because they all check for initialized state after getting
802 // the lock and return.
803 void InstanceKlass::fence_and_clear_init_lock() {
804 // make sure previous stores are all done, notably the init_state.
805 OrderAccess::storestore();
806 java_lang_Class::clear_init_lock(java_mirror());
807 assert(!is_not_initialized(), "class must be initialized now");
808 }
809
810
811 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
812 // process. The step comments refers to the procedure described in that section.
813 // Note: implementation moved to static method to expose the this pointer.
814 void InstanceKlass::initialize(TRAPS) {
815 if (this->should_be_initialized()) {
816 initialize_impl(CHECK);
817 // Note: at this point the class may be initialized
818 // OR it may be in the state of being initialized
819 // in case of recursive initialization!
820 } else {
821 assert(is_initialized(), "sanity check");
822 }
823 }
824
825 #ifdef ASSERT
826 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
827 assert(has_aot_initialized_mirror(), "must be");
828
829 InstanceKlass* s = java_super();
830 if (s != nullptr) {
831 DEBUG_ONLY(ResourceMark rm);
832 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
833 s->external_name(), external_name());
834 s->assert_no_clinit_will_run_for_aot_initialized_class();
835 }
836
837 Array<InstanceKlass*>* interfaces = local_interfaces();
838 int len = interfaces->length();
839 for (int i = 0; i < len; i++) {
840 InstanceKlass* intf = interfaces->at(i);
841 if (!intf->is_initialized()) {
842 ResourceMark rm;
843 // Note: an interface needs to be marked as is_initialized() only if
844 // - it has a <clinit>
845 // - it has declared a default method.
846 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
847 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
848 intf->external_name(), external_name());
849 }
850 }
851 }
852 #endif
853
854 #if INCLUDE_CDS
855 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
856 assert(has_aot_initialized_mirror(), "must be");
857 assert(CDSConfig::is_loading_heap(), "must be");
858 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
859 assert_no_clinit_will_run_for_aot_initialized_class();
860
861 if (is_initialized()) {
862 return;
863 }
864
865 if (is_runtime_setup_required()) {
866 // Need to take the slow path, which will call the runtimeSetup() function instead
867 // of <clinit>
868 initialize(CHECK);
869 return;
870 }
871 if (log_is_enabled(Info, aot, init)) {
872 ResourceMark rm;
873 log_info(aot, init)("%s (aot-inited)", external_name());
874 }
875
876 link_class(CHECK);
877
878 #ifdef ASSERT
879 {
880 Handle h_init_lock(THREAD, init_lock());
881 ObjectLocker ol(h_init_lock, THREAD);
882 assert(!is_initialized(), "sanity");
883 assert(!is_being_initialized(), "sanity");
884 assert(!is_in_error_state(), "sanity");
885 }
886 #endif
887
888 set_init_thread(THREAD);
889 set_initialization_state_and_notify(fully_initialized, CHECK);
890 AOTClassInitializer::call_runtime_setup(THREAD, this);
891 }
892 #endif
893
894 bool InstanceKlass::verify_code(TRAPS) {
895 // 1) Verify the bytecodes
896 return Verifier::verify(this, should_verify_class(), THREAD);
897 }
898
899 void InstanceKlass::link_class(TRAPS) {
900 assert(is_loaded(), "must be loaded");
901 if (!is_linked()) {
902 link_class_impl(CHECK);
903 }
904 }
905
906 // Called to verify that a class can link during initialization, without
907 // throwing a VerifyError.
908 bool InstanceKlass::link_class_or_fail(TRAPS) {
909 assert(is_loaded(), "must be loaded");
910 if (!is_linked()) {
911 link_class_impl(CHECK_false);
912 }
913 return is_linked();
914 }
915
916 bool InstanceKlass::link_class_impl(TRAPS) {
917 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
918 // This is for CDS static dump only -- we use the in_error_state to indicate that
919 // the class has failed verification. Throwing the NoClassDefFoundError here is just
920 // a convenient way to stop repeat attempts to verify the same (bad) class.
921 //
922 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
923 // if we are executing Java code. This is not a problem for CDS dumping phase since
924 // it doesn't execute any Java code.
925 ResourceMark rm(THREAD);
926 // Names are all known to be < 64k so we know this formatted message is not excessively large.
927 Exceptions::fthrow(THREAD_AND_LOCATION,
928 vmSymbols::java_lang_NoClassDefFoundError(),
929 "Class %s, or one of its supertypes, failed class initialization",
930 external_name());
931 return false;
932 }
933 // return if already verified
934 if (is_linked()) {
935 return true;
936 }
937
938 // Timing
939 // timer handles recursion
940 JavaThread* jt = THREAD;
941
942 // link super class before linking this class
943 Klass* super_klass = super();
944 if (super_klass != nullptr) {
945 if (super_klass->is_interface()) { // check if super class is an interface
946 ResourceMark rm(THREAD);
947 // Names are all known to be < 64k so we know this formatted message is not excessively large.
948 Exceptions::fthrow(
949 THREAD_AND_LOCATION,
950 vmSymbols::java_lang_IncompatibleClassChangeError(),
951 "class %s has interface %s as super class",
952 external_name(),
953 super_klass->external_name()
954 );
955 return false;
956 }
957
958 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
959 ik_super->link_class_impl(CHECK_false);
960 }
961
962 // link all interfaces implemented by this class before linking this class
963 Array<InstanceKlass*>* interfaces = local_interfaces();
964 int num_interfaces = interfaces->length();
965 for (int index = 0; index < num_interfaces; index++) {
966 InstanceKlass* interk = interfaces->at(index);
967 interk->link_class_impl(CHECK_false);
968 }
969
970 // in case the class is linked in the process of linking its superclasses
971 if (is_linked()) {
972 return true;
973 }
974
975 // trace only the link time for this klass that includes
976 // the verification time
977 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
978 ClassLoader::perf_class_link_selftime(),
979 ClassLoader::perf_classes_linked(),
980 jt->get_thread_stat()->perf_recursion_counts_addr(),
981 jt->get_thread_stat()->perf_timers_addr(),
982 PerfClassTraceTime::CLASS_LINK);
983
984 // verification & rewriting
985 {
986 HandleMark hm(THREAD);
987 Handle h_init_lock(THREAD, init_lock());
988 ObjectLocker ol(h_init_lock, jt);
989 // rewritten will have been set if loader constraint error found
990 // on an earlier link attempt
991 // don't verify or rewrite if already rewritten
992 //
993
994 if (!is_linked()) {
995 if (!is_rewritten()) {
996 if (is_shared()) {
997 assert(!verified_at_dump_time(), "must be");
998 }
999 {
1000 bool verify_ok = verify_code(THREAD);
1001 if (!verify_ok) {
1002 return false;
1003 }
1004 }
1005
1006 // Just in case a side-effect of verify linked this class already
1007 // (which can sometimes happen since the verifier loads classes
1008 // using custom class loaders, which are free to initialize things)
1009 if (is_linked()) {
1010 return true;
1011 }
1012
1013 // also sets rewritten
1014 rewrite_class(CHECK_false);
1015 } else if (is_shared()) {
1016 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1017 }
1018
1019 // relocate jsrs and link methods after they are all rewritten
1020 link_methods(CHECK_false);
1021
1022 // Initialize the vtable and interface table after
1023 // methods have been rewritten since rewrite may
1024 // fabricate new Method*s.
1025 // also does loader constraint checking
1026 //
1027 // initialize_vtable and initialize_itable need to be rerun
1028 // for a shared class if
1029 // 1) the class is loaded by custom class loader or
1030 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1031 // 3) the class was not verified during dump time
1032 bool need_init_table = true;
1033 if (is_shared() && verified_at_dump_time() &&
1034 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1035 need_init_table = false;
1036 }
1037 if (need_init_table) {
1038 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1039 itable().initialize_itable_and_check_constraints(CHECK_false);
1040 }
1041 #ifdef ASSERT
1042 vtable().verify(tty, true);
1043 // In case itable verification is ever added.
1044 // itable().verify(tty, true);
1045 #endif
1046 if (Universe::is_fully_initialized()) {
1047 DeoptimizationScope deopt_scope;
1048 {
1049 // Now mark all code that assumes the class is not linked.
1050 // Set state under the Compile_lock also.
1051 MutexLocker ml(THREAD, Compile_lock);
1052
1053 set_init_state(linked);
1054 CodeCache::mark_dependents_on(&deopt_scope, this);
1055 }
1056 // Perform the deopt handshake outside Compile_lock.
1057 deopt_scope.deoptimize_marked();
1058 } else {
1059 set_init_state(linked);
1060 }
1061 if (JvmtiExport::should_post_class_prepare()) {
1062 JvmtiExport::post_class_prepare(THREAD, this);
1063 }
1064 }
1065 }
1066 return true;
1067 }
1068
1069 // Rewrite the byte codes of all of the methods of a class.
1070 // The rewriter must be called exactly once. Rewriting must happen after
1071 // verification but before the first method of the class is executed.
1072 void InstanceKlass::rewrite_class(TRAPS) {
1073 assert(is_loaded(), "must be loaded");
1074 if (is_rewritten()) {
1075 assert(is_shared(), "rewriting an unshared class?");
1076 return;
1077 }
1078 Rewriter::rewrite(this, CHECK);
1079 set_rewritten();
1080 }
1081
1082 // Now relocate and link method entry points after class is rewritten.
1083 // This is outside is_rewritten flag. In case of an exception, it can be
1084 // executed more than once.
1085 void InstanceKlass::link_methods(TRAPS) {
1086 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1087
1088 int len = methods()->length();
1089 for (int i = len-1; i >= 0; i--) {
1090 methodHandle m(THREAD, methods()->at(i));
1091 RuntimeUpcalls::install_upcalls(m);
1092
1093 // Set up method entry points for compiler and interpreter .
1094 m->link_method(m, CHECK);
1095 }
1096 }
1097
1098 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1099 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1100 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1101 for (int i = 0; i < local_interfaces()->length(); ++i) {
1102 InstanceKlass* ik = local_interfaces()->at(i);
1103
1104 // Initialization is depth first search ie. we start with top of the inheritance tree
1105 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1106 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1107 if (ik->has_nonstatic_concrete_methods()) {
1108 ik->initialize_super_interfaces(CHECK);
1109 }
1110
1111 // Only initialize() interfaces that "declare" concrete methods.
1112 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1113 ik->initialize(CHECK);
1114 }
1115 }
1116 }
1117
1118 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1119 static InitializationErrorTable* _initialization_error_table;
1120
1121 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1122 // Create the same exception with a message indicating the thread name,
1123 // and the StackTraceElements.
1124 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1125 ResourceMark rm(current);
1126 if (init_error.is_null()) {
1127 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1128
1129 // We failed to create the new exception, most likely due to either out-of-memory or
1130 // a stackoverflow error. If the original exception was either of those then we save
1131 // the shared, pre-allocated, stackless, instance of that exception.
1132 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1133 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1134 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1135 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1136 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1137 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1138 } else {
1139 return;
1140 }
1141 }
1142
1143 MutexLocker ml(current, ClassInitError_lock);
1144 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1145 bool created;
1146 if (_initialization_error_table == nullptr) {
1147 _initialization_error_table = new (mtClass) InitializationErrorTable();
1148 }
1149 _initialization_error_table->put_if_absent(this, elem, &created);
1150 assert(created, "Initialization is single threaded");
1151 log_trace(class, init)("Initialization error added for class %s", external_name());
1152 }
1153
1154 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1155 MutexLocker ml(current, ClassInitError_lock);
1156 if (_initialization_error_table == nullptr) {
1157 return nullptr;
1158 }
1159 OopHandle* h = _initialization_error_table->get(this);
1160 return (h != nullptr) ? h->resolve() : nullptr;
1161 }
1162
1163 // Need to remove entries for unloaded classes.
1164 void InstanceKlass::clean_initialization_error_table() {
1165 struct InitErrorTableCleaner {
1166 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1167 if (!ik->is_loader_alive()) {
1168 h.release(Universe::vm_global());
1169 return true;
1170 } else {
1171 return false;
1172 }
1173 }
1174 };
1175
1176 assert_locked_or_safepoint(ClassInitError_lock);
1177 InitErrorTableCleaner cleaner;
1178 if (_initialization_error_table != nullptr) {
1179 _initialization_error_table->unlink(&cleaner);
1180 }
1181 }
1182
1183 void InstanceKlass::initialize_impl(TRAPS) {
1184 HandleMark hm(THREAD);
1185
1186 // Make sure klass is linked (verified) before initialization
1187 // A class could already be verified, since it has been reflected upon.
1188 link_class(CHECK);
1189
1190 DTRACE_CLASSINIT_PROBE(required, -1);
1191
1192 bool wait = false;
1193
1194 JavaThread* jt = THREAD;
1195
1196 if (ForceProfiling) {
1197 // Preallocate MDOs.
1198 for (int i = 0; i < methods()->length(); i++) {
1199 assert(!HAS_PENDING_EXCEPTION, "");
1200 methodHandle m(THREAD, methods()->at(i));
1201 Method::build_profiling_method_data(m, THREAD);
1202 if (HAS_PENDING_EXCEPTION) {
1203 ResourceMark rm;
1204 log_warning(cds)("MDO preallocation failed for %s", external_name());
1205 CLEAR_PENDING_EXCEPTION;
1206 break;
1207 }
1208 }
1209 }
1210
1211 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1212
1213 // refer to the JVM book page 47 for description of steps
1214 // Step 1
1215 {
1216 Handle h_init_lock(THREAD, init_lock());
1217 ObjectLocker ol(h_init_lock, jt);
1218
1219 // Step 2
1220 // If we were to use wait() instead of waitInterruptibly() then
1221 // we might end up throwing IE from link/symbol resolution sites
1222 // that aren't expected to throw. This would wreak havoc. See 6320309.
1223 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1224 if (debug_logging_enabled) {
1225 ResourceMark rm(jt);
1226 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1227 jt->name(), external_name(), init_thread_name());
1228 }
1229 wait = true;
1230 jt->set_class_to_be_initialized(this);
1231 ol.wait_uninterruptibly(jt);
1232 jt->set_class_to_be_initialized(nullptr);
1233 }
1234
1235 // Step 3
1236 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1237 if (debug_logging_enabled) {
1238 ResourceMark rm(jt);
1239 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1240 jt->name(), external_name());
1241 }
1242 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1243 return;
1244 }
1245
1246 // Step 4
1247 if (is_initialized()) {
1248 if (debug_logging_enabled) {
1249 ResourceMark rm(jt);
1250 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1251 jt->name(), external_name());
1252 }
1253 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1254 return;
1255 }
1256
1257 // Step 5
1258 if (is_in_error_state()) {
1259 if (debug_logging_enabled) {
1260 ResourceMark rm(jt);
1261 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1262 jt->name(), external_name());
1263 }
1264
1265 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1266 ResourceMark rm(THREAD);
1267 Handle cause(THREAD, get_initialization_error(THREAD));
1268
1269 stringStream ss;
1270 ss.print("Could not initialize class %s", external_name());
1271 if (cause.is_null()) {
1272 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1273 } else {
1274 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1275 ss.as_string(), cause);
1276 }
1277 } else {
1278
1279 // Step 6
1280 set_init_state(being_initialized);
1281 set_init_thread(jt);
1282 if (debug_logging_enabled) {
1283 ResourceMark rm(jt);
1284 log_debug(class, init)("Thread \"%s\" is initializing %s",
1285 jt->name(), external_name());
1286 }
1287 }
1288 }
1289
1290 // Step 7
1291 // Next, if C is a class rather than an interface, initialize it's super class and super
1292 // interfaces.
1293 if (!is_interface()) {
1294 Klass* super_klass = super();
1295 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1296 super_klass->initialize(THREAD);
1297 }
1298 // If C implements any interface that declares a non-static, concrete method,
1299 // the initialization of C triggers initialization of its super interfaces.
1300 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1301 // having a superinterface that declares, non-static, concrete methods
1302 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1303 initialize_super_interfaces(THREAD);
1304 }
1305
1306 // If any exceptions, complete abruptly, throwing the same exception as above.
1307 if (HAS_PENDING_EXCEPTION) {
1308 Handle e(THREAD, PENDING_EXCEPTION);
1309 CLEAR_PENDING_EXCEPTION;
1310 {
1311 EXCEPTION_MARK;
1312 add_initialization_error(THREAD, e);
1313 // Locks object, set state, and notify all waiting threads
1314 set_initialization_state_and_notify(initialization_error, THREAD);
1315 CLEAR_PENDING_EXCEPTION;
1316 }
1317 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1318 THROW_OOP(e());
1319 }
1320 }
1321
1322
1323 // Step 8
1324 {
1325 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1326 if (class_initializer() != nullptr) {
1327 // Timer includes any side effects of class initialization (resolution,
1328 // etc), but not recursive entry into call_class_initializer().
1329 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1330 ClassLoader::perf_class_init_selftime(),
1331 ClassLoader::perf_classes_inited(),
1332 jt->get_thread_stat()->perf_recursion_counts_addr(),
1333 jt->get_thread_stat()->perf_timers_addr(),
1334 PerfClassTraceTime::CLASS_CLINIT);
1335 call_class_initializer(THREAD);
1336 } else {
1337 // The elapsed time is so small it's not worth counting.
1338 if (UsePerfData) {
1339 ClassLoader::perf_classes_inited()->inc();
1340 }
1341 call_class_initializer(THREAD);
1342 }
1343 }
1344
1345 // Step 9
1346 if (!HAS_PENDING_EXCEPTION) {
1347 set_initialization_state_and_notify(fully_initialized, CHECK);
1348 DEBUG_ONLY(vtable().verify(tty, true);)
1349 CompilationPolicy::replay_training_at_init(this, THREAD);
1350 }
1351 else {
1352 // Step 10 and 11
1353 Handle e(THREAD, PENDING_EXCEPTION);
1354 CLEAR_PENDING_EXCEPTION;
1355 // JVMTI has already reported the pending exception
1356 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1357 JvmtiExport::clear_detected_exception(jt);
1358 {
1359 EXCEPTION_MARK;
1360 add_initialization_error(THREAD, e);
1361 set_initialization_state_and_notify(initialization_error, THREAD);
1362 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1363 // JVMTI has already reported the pending exception
1364 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1365 JvmtiExport::clear_detected_exception(jt);
1366 }
1367 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1368 if (e->is_a(vmClasses::Error_klass())) {
1369 THROW_OOP(e());
1370 } else {
1371 JavaCallArguments args(e);
1372 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1373 vmSymbols::throwable_void_signature(),
1374 &args);
1375 }
1376 }
1377 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1378 }
1379
1380 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1381 Handle h_init_lock(THREAD, init_lock());
1382 if (h_init_lock() != nullptr) {
1383 ObjectLocker ol(h_init_lock, THREAD);
1384 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1385 set_init_state(state);
1386 fence_and_clear_init_lock();
1387 ol.notify_all(CHECK);
1388 } else {
1389 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1390 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1391 set_init_state(state);
1392 }
1393 }
1394
1395 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1396 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1397 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1398 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1399
1400 DeoptimizationScope deopt_scope;
1401 {
1402 MutexLocker ml(current, Compile_lock);
1403
1404 set_init_state(InstanceKlass::loaded);
1405 // make sure init_state store is already done.
1406 // The compiler reads the hierarchy outside of the Compile_lock.
1407 // Access ordering is used to add to hierarchy.
1408
1409 // Link into hierarchy.
1410 append_to_sibling_list(); // add to superklass/sibling list
1411 process_interfaces(); // handle all "implements" declarations
1412
1413 // Now mark all code that depended on old class hierarchy.
1414 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1415 if (Universe::is_fully_initialized()) {
1416 CodeCache::mark_dependents_on(&deopt_scope, this);
1417 }
1418 }
1419 // Perform the deopt handshake outside Compile_lock.
1420 deopt_scope.deoptimize_marked();
1421 }
1422
1423
1424 InstanceKlass* InstanceKlass::implementor() const {
1425 InstanceKlass* volatile* ik = adr_implementor();
1426 if (ik == nullptr) {
1427 return nullptr;
1428 } else {
1429 // This load races with inserts, and therefore needs acquire.
1430 InstanceKlass* ikls = Atomic::load_acquire(ik);
1431 if (ikls != nullptr && !ikls->is_loader_alive()) {
1432 return nullptr; // don't return unloaded class
1433 } else {
1434 return ikls;
1435 }
1436 }
1437 }
1438
1439
1440 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1441 assert_locked_or_safepoint(Compile_lock);
1442 assert(is_interface(), "not interface");
1443 InstanceKlass* volatile* addr = adr_implementor();
1444 assert(addr != nullptr, "null addr");
1445 if (addr != nullptr) {
1446 Atomic::release_store(addr, ik);
1447 }
1448 }
1449
1450 int InstanceKlass::nof_implementors() const {
1451 InstanceKlass* ik = implementor();
1452 if (ik == nullptr) {
1453 return 0;
1454 } else if (ik != this) {
1455 return 1;
1456 } else {
1457 return 2;
1458 }
1459 }
1460
1461 // The embedded _implementor field can only record one implementor.
1462 // When there are more than one implementors, the _implementor field
1463 // is set to the interface Klass* itself. Following are the possible
1464 // values for the _implementor field:
1465 // null - no implementor
1466 // implementor Klass* - one implementor
1467 // self - more than one implementor
1468 //
1469 // The _implementor field only exists for interfaces.
1470 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1471 if (Universe::is_fully_initialized()) {
1472 assert_lock_strong(Compile_lock);
1473 }
1474 assert(is_interface(), "not interface");
1475 // Filter out my subinterfaces.
1476 // (Note: Interfaces are never on the subklass list.)
1477 if (ik->is_interface()) return;
1478
1479 // Filter out subclasses whose supers already implement me.
1480 // (Note: CHA must walk subclasses of direct implementors
1481 // in order to locate indirect implementors.)
1482 InstanceKlass* super_ik = ik->java_super();
1483 if (super_ik != nullptr && super_ik->implements_interface(this))
1484 // We only need to check one immediate superclass, since the
1485 // implements_interface query looks at transitive_interfaces.
1486 // Any supers of the super have the same (or fewer) transitive_interfaces.
1487 return;
1488
1489 InstanceKlass* iklass = implementor();
1490 if (iklass == nullptr) {
1491 set_implementor(ik);
1492 } else if (iklass != this && iklass != ik) {
1493 // There is already an implementor. Use itself as an indicator of
1494 // more than one implementors.
1495 set_implementor(this);
1496 }
1497
1498 // The implementor also implements the transitive_interfaces
1499 for (int index = 0; index < local_interfaces()->length(); index++) {
1500 local_interfaces()->at(index)->add_implementor(ik);
1501 }
1502 }
1503
1504 void InstanceKlass::init_implementor() {
1505 if (is_interface()) {
1506 set_implementor(nullptr);
1507 }
1508 }
1509
1510
1511 void InstanceKlass::process_interfaces() {
1512 // link this class into the implementors list of every interface it implements
1513 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1514 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1515 InstanceKlass* interf = local_interfaces()->at(i);
1516 assert(interf->is_interface(), "expected interface");
1517 interf->add_implementor(this);
1518 }
1519 }
1520
1521 bool InstanceKlass::can_be_primary_super_slow() const {
1522 if (is_interface())
1523 return false;
1524 else
1525 return Klass::can_be_primary_super_slow();
1526 }
1527
1528 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1529 Array<InstanceKlass*>* transitive_interfaces) {
1530 // The secondaries are the implemented interfaces.
1531 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1532 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1533 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1534 int num_secondaries = num_extra_slots + interfaces->length();
1535 if (num_secondaries == 0) {
1536 // Must share this for correct bootstrapping!
1537 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1538 return nullptr;
1539 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1540 // We will reuse the transitive interfaces list if we're certain
1541 // it's in hash order.
1542 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1543 set_secondary_supers(interfaces, bitmap);
1544 return nullptr;
1545 }
1546 // Copy transitive interfaces to a temporary growable array to be constructed
1547 // into the secondary super list with extra slots.
1548 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1549 for (int i = 0; i < interfaces->length(); i++) {
1550 secondaries->push(interfaces->at(i));
1551 }
1552 return secondaries;
1553 }
1554
1555 bool InstanceKlass::implements_interface(Klass* k) const {
1556 if (this == k) return true;
1557 assert(k->is_interface(), "should be an interface class");
1558 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1559 if (transitive_interfaces()->at(i) == k) {
1560 return true;
1561 }
1562 }
1563 return false;
1564 }
1565
1566 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1567 // Verify direct super interface
1568 if (this == k) return true;
1569 assert(k->is_interface(), "should be an interface class");
1570 for (int i = 0; i < local_interfaces()->length(); i++) {
1571 if (local_interfaces()->at(i) == k) {
1572 return true;
1573 }
1574 }
1575 return false;
1576 }
1577
1578 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1579 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1580 size_t size = objArrayOopDesc::object_size(length);
1581 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1582 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1583 /* do_zero */ true, CHECK_NULL);
1584 return o;
1585 }
1586
1587 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1588 if (TraceFinalizerRegistration) {
1589 tty->print("Registered ");
1590 i->print_value_on(tty);
1591 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1592 }
1593 instanceHandle h_i(THREAD, i);
1594 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1595 JavaValue result(T_VOID);
1596 JavaCallArguments args(h_i);
1597 methodHandle mh(THREAD, Universe::finalizer_register_method());
1598 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1599 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1600 return h_i();
1601 }
1602
1603 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1604 assert(!is_abstract() && !is_interface(), "Should not create this object");
1605 size_t size = size_helper(); // Query before forming handle.
1606 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1607 }
1608
1609 instanceOop InstanceKlass::allocate_instance(oop java_class,
1610 const char* who,
1611 TRAPS) {
1612 Klass* k = java_lang_Class::as_Klass(java_class);
1613 if (k == nullptr) {
1614 ResourceMark rm(THREAD);
1615 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1616 }
1617 InstanceKlass* ik = cast(k);
1618 ik->check_valid_for_instantiation(false, CHECK_NULL);
1619 ik->initialize(CHECK_NULL);
1620 return ik->allocate_instance(THREAD);
1621 }
1622
1623 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1624 return instanceHandle(THREAD, allocate_instance(THREAD));
1625 }
1626
1627 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1628 if (is_interface() || is_abstract()) {
1629 ResourceMark rm(THREAD);
1630 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1631 : vmSymbols::java_lang_InstantiationException(), external_name());
1632 }
1633 if (this == vmClasses::Class_klass()) {
1634 ResourceMark rm(THREAD);
1635 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1636 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1637 }
1638 }
1639
1640 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1641 // Need load-acquire for lock-free read
1642 if (array_klasses_acquire() == nullptr) {
1643
1644 // Recursively lock array allocation
1645 RecursiveLocker rl(MultiArray_lock, THREAD);
1646
1647 // Check if another thread created the array klass while we were waiting for the lock.
1648 if (array_klasses() == nullptr) {
1649 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1650 // use 'release' to pair with lock-free load
1651 release_set_array_klasses(k);
1652 }
1653 }
1654
1655 // array_klasses() will always be set at this point
1656 ObjArrayKlass* ak = array_klasses();
1657 assert(ak != nullptr, "should be set");
1658 return ak->array_klass(n, THREAD);
1659 }
1660
1661 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1662 // Need load-acquire for lock-free read
1663 ObjArrayKlass* oak = array_klasses_acquire();
1664 if (oak == nullptr) {
1665 return nullptr;
1666 } else {
1667 return oak->array_klass_or_null(n);
1668 }
1669 }
1670
1671 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1672 return array_klass(1, THREAD);
1673 }
1674
1675 ArrayKlass* InstanceKlass::array_klass_or_null() {
1676 return array_klass_or_null(1);
1677 }
1678
1679 static int call_class_initializer_counter = 0; // for debugging
1680
1681 Method* InstanceKlass::class_initializer() const {
1682 Method* clinit = find_method(
1683 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1684 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1685 return clinit;
1686 }
1687 return nullptr;
1688 }
1689
1690 void InstanceKlass::call_class_initializer(TRAPS) {
1691 if (ReplayCompiles &&
1692 (ReplaySuppressInitializers == 1 ||
1693 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1694 // Hide the existence of the initializer for the purpose of replaying the compile
1695 return;
1696 }
1697
1698 #if INCLUDE_CDS
1699 // This is needed to ensure the consistency of the archived heap objects.
1700 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1701 AOTClassInitializer::call_runtime_setup(THREAD, this);
1702 return;
1703 } else if (has_archived_enum_objs()) {
1704 assert(is_shared(), "must be");
1705 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1706 if (initialized) {
1707 return;
1708 }
1709 }
1710 #endif
1711
1712 methodHandle h_method(THREAD, class_initializer());
1713 assert(!is_initialized(), "we cannot initialize twice");
1714
1715 #if 0
1716 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1717 int init_id = log_class_init(THREAD, this);
1718 if (h_method() != nullptr) {
1719 JavaCallArguments args; // No arguments
1720 JavaValue result(T_VOID);
1721 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1722 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1723
1724 elapsedTimer timer;
1725 {
1726 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1727 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1728
1729 timer.start();
1730 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1731 timer.stop();
1732 }
1733
1734 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1735
1736 jlong bc_executed = (bc_end - bc_start);
1737 if (UsePerfData && outer == nullptr) { // outermost clinit
1738 THREAD->inc_clinit_bc_counter_value(bc_executed);
1739 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1740 }
1741
1742 THREAD->set_class_being_initialized(outer);
1743
1744 LogStreamHandle(Debug, init) log;
1745 if (log.is_enabled()) {
1746 ResourceMark rm(THREAD);
1747 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1748 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1749 if (CountBytecodes || CountBytecodesPerThread) {
1750 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1751 }
1752 name()->print_value_on(&log);
1753 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1754 p2i(THREAD), THREAD->name(), p2i(this));
1755 }
1756 }
1757 LogTarget(Info, class, init) lt;
1758 if (lt.is_enabled()) {
1759 ResourceMark rm(THREAD);
1760 LogStream ls(lt);
1761 ls.print("%d Initialized ", init_id);
1762 name()->print_value_on(&ls);
1763 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1764 h_method() == nullptr ? "(no method)" : "", p2i(this),
1765 THREAD->name());
1766 }
1767 #else
1768 LogTarget(Info, class, init) lt;
1769 if (lt.is_enabled()) {
1770 ResourceMark rm(THREAD);
1771 LogStream ls(lt);
1772 ls.print("%d Initializing ", call_class_initializer_counter++);
1773 name()->print_value_on(&ls);
1774 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1775 h_method() == nullptr ? "(no method)" : "", p2i(this),
1776 THREAD->name());
1777 }
1778 if (h_method() != nullptr) {
1779 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1780 JavaCallArguments args; // No arguments
1781 JavaValue result(T_VOID);
1782 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1783 }
1784 #endif
1785 }
1786
1787 // If a class that implements this interface is initialized, is the JVM required
1788 // to first execute a <clinit> method declared in this interface,
1789 // or (if also_check_supers==true) any of the super types of this interface?
1790 //
1791 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1792 // an interface, then let SC be its superclass and let SI1, ..., SIn
1793 // be all superinterfaces of C (whether direct or indirect) that
1794 // declare at least one non-abstract, non-static method.
1795 //
1796 // So when an interface is initialized, it does not look at its
1797 // supers. But a proper class will ensure that all of its supers have
1798 // run their <clinit> methods, except that it disregards interfaces
1799 // that lack a non-static concrete method (i.e., a default method).
1800 // Therefore, you should probably call this method only when the
1801 // current class is a super of some proper class, not an interface.
1802 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1803 assert(is_interface(), "must be");
1804
1805 if (!has_nonstatic_concrete_methods()) {
1806 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1807 return false;
1808 }
1809
1810 // JVMS 5.5. Initialization
1811 // ...If C is an interface that declares a non-abstract,
1812 // non-static method, the initialization of a class that
1813 // implements C directly or indirectly.
1814 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1815 return true;
1816 }
1817 if (also_check_supers) {
1818 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1819 for (int i = 0; i < all_ifs->length(); ++i) {
1820 InstanceKlass* super_intf = all_ifs->at(i);
1821 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1822 return true;
1823 }
1824 }
1825 }
1826 return false;
1827 }
1828
1829 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1830 InterpreterOopMap* entry_for) {
1831 // Lazily create the _oop_map_cache at first request.
1832 // Load_acquire is needed to safely get instance published with CAS by another thread.
1833 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1834 if (oop_map_cache == nullptr) {
1835 // Try to install new instance atomically.
1836 oop_map_cache = new OopMapCache();
1837 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1838 if (other != nullptr) {
1839 // Someone else managed to install before us, ditch local copy and use the existing one.
1840 delete oop_map_cache;
1841 oop_map_cache = other;
1842 }
1843 }
1844 // _oop_map_cache is constant after init; lookup below does its own locking.
1845 oop_map_cache->lookup(method, bci, entry_for);
1846 }
1847
1848 bool InstanceKlass::contains_field_offset(int offset) {
1849 fieldDescriptor fd;
1850 return find_field_from_offset(offset, false, &fd);
1851 }
1852
1853 FieldInfo InstanceKlass::field(int index) const {
1854 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1855 if (fs.index() == index) {
1856 return fs.to_FieldInfo();
1857 }
1858 }
1859 fatal("Field not found");
1860 return FieldInfo();
1861 }
1862
1863 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1864 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1865 Symbol* f_name = fs.name();
1866 Symbol* f_sig = fs.signature();
1867 if (f_name == name && f_sig == sig) {
1868 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1869 return true;
1870 }
1871 }
1872 return false;
1873 }
1874
1875
1876 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1877 const int n = local_interfaces()->length();
1878 for (int i = 0; i < n; i++) {
1879 Klass* intf1 = local_interfaces()->at(i);
1880 assert(intf1->is_interface(), "just checking type");
1881 // search for field in current interface
1882 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1883 assert(fd->is_static(), "interface field must be static");
1884 return intf1;
1885 }
1886 // search for field in direct superinterfaces
1887 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1888 if (intf2 != nullptr) return intf2;
1889 }
1890 // otherwise field lookup fails
1891 return nullptr;
1892 }
1893
1894
1895 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1896 // search order according to newest JVM spec (5.4.3.2, p.167).
1897 // 1) search for field in current klass
1898 if (find_local_field(name, sig, fd)) {
1899 return const_cast<InstanceKlass*>(this);
1900 }
1901 // 2) search for field recursively in direct superinterfaces
1902 { Klass* intf = find_interface_field(name, sig, fd);
1903 if (intf != nullptr) return intf;
1904 }
1905 // 3) apply field lookup recursively if superclass exists
1906 { Klass* supr = super();
1907 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1908 }
1909 // 4) otherwise field lookup fails
1910 return nullptr;
1911 }
1912
1913
1914 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1915 // search order according to newest JVM spec (5.4.3.2, p.167).
1916 // 1) search for field in current klass
1917 if (find_local_field(name, sig, fd)) {
1918 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1919 }
1920 // 2) search for field recursively in direct superinterfaces
1921 if (is_static) {
1922 Klass* intf = find_interface_field(name, sig, fd);
1923 if (intf != nullptr) return intf;
1924 }
1925 // 3) apply field lookup recursively if superclass exists
1926 { Klass* supr = super();
1927 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1928 }
1929 // 4) otherwise field lookup fails
1930 return nullptr;
1931 }
1932
1933
1934 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1935 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1936 if (fs.offset() == offset) {
1937 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1938 if (fd->is_static() == is_static) return true;
1939 }
1940 }
1941 return false;
1942 }
1943
1944
1945 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1946 Klass* klass = const_cast<InstanceKlass*>(this);
1947 while (klass != nullptr) {
1948 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1949 return true;
1950 }
1951 klass = klass->super();
1952 }
1953 return false;
1954 }
1955
1956
1957 void InstanceKlass::methods_do(void f(Method* method)) {
1958 // Methods aren't stable until they are loaded. This can be read outside
1959 // a lock through the ClassLoaderData for profiling
1960 // Redefined scratch classes are on the list and need to be cleaned
1961 if (!is_loaded() && !is_scratch_class()) {
1962 return;
1963 }
1964
1965 int len = methods()->length();
1966 for (int index = 0; index < len; index++) {
1967 Method* m = methods()->at(index);
1968 assert(m->is_method(), "must be method");
1969 f(m);
1970 }
1971 }
1972
1973
1974 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1975 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1976 if (fs.access_flags().is_static()) {
1977 fieldDescriptor& fd = fs.field_descriptor();
1978 cl->do_field(&fd);
1979 }
1980 }
1981 }
1982
1983
1984 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1985 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1986 if (fs.access_flags().is_static()) {
1987 fieldDescriptor& fd = fs.field_descriptor();
1988 f(&fd, mirror, CHECK);
1989 }
1990 }
1991 }
1992
1993 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1994 InstanceKlass* super = superklass();
1995 if (super != nullptr) {
1996 super->do_nonstatic_fields(cl);
1997 }
1998 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1999 fieldDescriptor& fd = fs.field_descriptor();
2000 if (!fd.is_static()) {
2001 cl->do_field(&fd);
2002 }
2003 }
2004 }
2005
2006 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2007 return a->offset() - b->offset();
2008 }
2009
2010 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2011 InstanceKlass* super = superklass();
2012 if (super != nullptr) {
2013 super->print_nonstatic_fields(cl);
2014 }
2015 ResourceMark rm;
2016 // In DebugInfo nonstatic fields are sorted by offset.
2017 GrowableArray<FieldInfo> fields_sorted;
2018 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2019 if (!fs.access_flags().is_static()) {
2020 fields_sorted.push(fs.to_FieldInfo());
2021 }
2022 }
2023 int length = fields_sorted.length();
2024 if (length > 0) {
2025 fields_sorted.sort(compare_fields_by_offset);
2026 fieldDescriptor fd;
2027 for (int i = 0; i < length; i++) {
2028 fd.reinitialize(this, fields_sorted.at(i));
2029 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2030 cl->do_field(&fd);
2031 }
2032 }
2033 }
2034
2035 #ifdef ASSERT
2036 static int linear_search(const Array<Method*>* methods,
2037 const Symbol* name,
2038 const Symbol* signature) {
2039 const int len = methods->length();
2040 for (int index = 0; index < len; index++) {
2041 const Method* const m = methods->at(index);
2042 assert(m->is_method(), "must be method");
2043 if (m->signature() == signature && m->name() == name) {
2044 return index;
2045 }
2046 }
2047 return -1;
2048 }
2049 #endif
2050
2051 bool InstanceKlass::_disable_method_binary_search = false;
2052
2053 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2054 int len = methods->length();
2055 int l = 0;
2056 int h = len - 1;
2057 while (l <= h) {
2058 Method* m = methods->at(l);
2059 if (m->name() == name) {
2060 return l;
2061 }
2062 l++;
2063 }
2064 return -1;
2065 }
2066
2067 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2068 if (_disable_method_binary_search) {
2069 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2070 // At the final stage of dynamic dumping, the methods array may not be sorted
2071 // by ascending addresses of their names, so we can't use binary search anymore.
2072 // However, methods with the same name are still laid out consecutively inside the
2073 // methods array, so let's look for the first one that matches.
2074 return linear_search(methods, name);
2075 }
2076
2077 int len = methods->length();
2078 int l = 0;
2079 int h = len - 1;
2080
2081 // methods are sorted by ascending addresses of their names, so do binary search
2082 while (l <= h) {
2083 int mid = (l + h) >> 1;
2084 Method* m = methods->at(mid);
2085 assert(m->is_method(), "must be method");
2086 int res = m->name()->fast_compare(name);
2087 if (res == 0) {
2088 return mid;
2089 } else if (res < 0) {
2090 l = mid + 1;
2091 } else {
2092 h = mid - 1;
2093 }
2094 }
2095 return -1;
2096 }
2097
2098 // find_method looks up the name/signature in the local methods array
2099 Method* InstanceKlass::find_method(const Symbol* name,
2100 const Symbol* signature) const {
2101 return find_method_impl(name, signature,
2102 OverpassLookupMode::find,
2103 StaticLookupMode::find,
2104 PrivateLookupMode::find);
2105 }
2106
2107 Method* InstanceKlass::find_method_impl(const Symbol* name,
2108 const Symbol* signature,
2109 OverpassLookupMode overpass_mode,
2110 StaticLookupMode static_mode,
2111 PrivateLookupMode private_mode) const {
2112 return InstanceKlass::find_method_impl(methods(),
2113 name,
2114 signature,
2115 overpass_mode,
2116 static_mode,
2117 private_mode);
2118 }
2119
2120 // find_instance_method looks up the name/signature in the local methods array
2121 // and skips over static methods
2122 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2123 const Symbol* name,
2124 const Symbol* signature,
2125 PrivateLookupMode private_mode) {
2126 Method* const meth = InstanceKlass::find_method_impl(methods,
2127 name,
2128 signature,
2129 OverpassLookupMode::find,
2130 StaticLookupMode::skip,
2131 private_mode);
2132 assert(((meth == nullptr) || !meth->is_static()),
2133 "find_instance_method should have skipped statics");
2134 return meth;
2135 }
2136
2137 // find_instance_method looks up the name/signature in the local methods array
2138 // and skips over static methods
2139 Method* InstanceKlass::find_instance_method(const Symbol* name,
2140 const Symbol* signature,
2141 PrivateLookupMode private_mode) const {
2142 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2143 }
2144
2145 // Find looks up the name/signature in the local methods array
2146 // and filters on the overpass, static and private flags
2147 // This returns the first one found
2148 // note that the local methods array can have up to one overpass, one static
2149 // and one instance (private or not) with the same name/signature
2150 Method* InstanceKlass::find_local_method(const Symbol* name,
2151 const Symbol* signature,
2152 OverpassLookupMode overpass_mode,
2153 StaticLookupMode static_mode,
2154 PrivateLookupMode private_mode) const {
2155 return InstanceKlass::find_method_impl(methods(),
2156 name,
2157 signature,
2158 overpass_mode,
2159 static_mode,
2160 private_mode);
2161 }
2162
2163 // Find looks up the name/signature in the local methods array
2164 // and filters on the overpass, static and private flags
2165 // This returns the first one found
2166 // note that the local methods array can have up to one overpass, one static
2167 // and one instance (private or not) with the same name/signature
2168 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2169 const Symbol* name,
2170 const Symbol* signature,
2171 OverpassLookupMode overpass_mode,
2172 StaticLookupMode static_mode,
2173 PrivateLookupMode private_mode) {
2174 return InstanceKlass::find_method_impl(methods,
2175 name,
2176 signature,
2177 overpass_mode,
2178 static_mode,
2179 private_mode);
2180 }
2181
2182 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2183 const Symbol* name,
2184 const Symbol* signature) {
2185 return InstanceKlass::find_method_impl(methods,
2186 name,
2187 signature,
2188 OverpassLookupMode::find,
2189 StaticLookupMode::find,
2190 PrivateLookupMode::find);
2191 }
2192
2193 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2194 const Symbol* name,
2195 const Symbol* signature,
2196 OverpassLookupMode overpass_mode,
2197 StaticLookupMode static_mode,
2198 PrivateLookupMode private_mode) {
2199 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2200 return hit >= 0 ? methods->at(hit): nullptr;
2201 }
2202
2203 // true if method matches signature and conforms to skipping_X conditions.
2204 static bool method_matches(const Method* m,
2205 const Symbol* signature,
2206 bool skipping_overpass,
2207 bool skipping_static,
2208 bool skipping_private) {
2209 return ((m->signature() == signature) &&
2210 (!skipping_overpass || !m->is_overpass()) &&
2211 (!skipping_static || !m->is_static()) &&
2212 (!skipping_private || !m->is_private()));
2213 }
2214
2215 // Used directly for default_methods to find the index into the
2216 // default_vtable_indices, and indirectly by find_method
2217 // find_method_index looks in the local methods array to return the index
2218 // of the matching name/signature. If, overpass methods are being ignored,
2219 // the search continues to find a potential non-overpass match. This capability
2220 // is important during method resolution to prefer a static method, for example,
2221 // over an overpass method.
2222 // There is the possibility in any _method's array to have the same name/signature
2223 // for a static method, an overpass method and a local instance method
2224 // To correctly catch a given method, the search criteria may need
2225 // to explicitly skip the other two. For local instance methods, it
2226 // is often necessary to skip private methods
2227 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2228 const Symbol* name,
2229 const Symbol* signature,
2230 OverpassLookupMode overpass_mode,
2231 StaticLookupMode static_mode,
2232 PrivateLookupMode private_mode) {
2233 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2234 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2235 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2236 const int hit = quick_search(methods, name);
2237 if (hit != -1) {
2238 const Method* const m = methods->at(hit);
2239
2240 // Do linear search to find matching signature. First, quick check
2241 // for common case, ignoring overpasses if requested.
2242 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2243 return hit;
2244 }
2245
2246 // search downwards through overloaded methods
2247 int i;
2248 for (i = hit - 1; i >= 0; --i) {
2249 const Method* const m = methods->at(i);
2250 assert(m->is_method(), "must be method");
2251 if (m->name() != name) {
2252 break;
2253 }
2254 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2255 return i;
2256 }
2257 }
2258 // search upwards
2259 for (i = hit + 1; i < methods->length(); ++i) {
2260 const Method* const m = methods->at(i);
2261 assert(m->is_method(), "must be method");
2262 if (m->name() != name) {
2263 break;
2264 }
2265 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2266 return i;
2267 }
2268 }
2269 // not found
2270 #ifdef ASSERT
2271 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2272 linear_search(methods, name, signature);
2273 assert(-1 == index, "binary search should have found entry %d", index);
2274 #endif
2275 }
2276 return -1;
2277 }
2278
2279 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2280 return find_method_by_name(methods(), name, end);
2281 }
2282
2283 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2284 const Symbol* name,
2285 int* end_ptr) {
2286 assert(end_ptr != nullptr, "just checking");
2287 int start = quick_search(methods, name);
2288 int end = start + 1;
2289 if (start != -1) {
2290 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2291 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2292 *end_ptr = end;
2293 return start;
2294 }
2295 return -1;
2296 }
2297
2298 // uncached_lookup_method searches both the local class methods array and all
2299 // superclasses methods arrays, skipping any overpass methods in superclasses,
2300 // and possibly skipping private methods.
2301 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2302 const Symbol* signature,
2303 OverpassLookupMode overpass_mode,
2304 PrivateLookupMode private_mode) const {
2305 OverpassLookupMode overpass_local_mode = overpass_mode;
2306 const Klass* klass = this;
2307 while (klass != nullptr) {
2308 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2309 signature,
2310 overpass_local_mode,
2311 StaticLookupMode::find,
2312 private_mode);
2313 if (method != nullptr) {
2314 return method;
2315 }
2316 klass = klass->super();
2317 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2318 }
2319 return nullptr;
2320 }
2321
2322 #ifdef ASSERT
2323 // search through class hierarchy and return true if this class or
2324 // one of the superclasses was redefined
2325 bool InstanceKlass::has_redefined_this_or_super() const {
2326 const Klass* klass = this;
2327 while (klass != nullptr) {
2328 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2329 return true;
2330 }
2331 klass = klass->super();
2332 }
2333 return false;
2334 }
2335 #endif
2336
2337 // lookup a method in the default methods list then in all transitive interfaces
2338 // Do NOT return private or static methods
2339 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2340 Symbol* signature) const {
2341 Method* m = nullptr;
2342 if (default_methods() != nullptr) {
2343 m = find_method(default_methods(), name, signature);
2344 }
2345 // Look up interfaces
2346 if (m == nullptr) {
2347 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2348 }
2349 return m;
2350 }
2351
2352 // lookup a method in all the interfaces that this class implements
2353 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2354 // They should only be found in the initial InterfaceMethodRef
2355 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2356 Symbol* signature,
2357 DefaultsLookupMode defaults_mode) const {
2358 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2359 int num_ifs = all_ifs->length();
2360 InstanceKlass *ik = nullptr;
2361 for (int i = 0; i < num_ifs; i++) {
2362 ik = all_ifs->at(i);
2363 Method* m = ik->lookup_method(name, signature);
2364 if (m != nullptr && m->is_public() && !m->is_static() &&
2365 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2366 return m;
2367 }
2368 }
2369 return nullptr;
2370 }
2371
2372 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2373 :_st(st), _verbose(verbose) {
2374 ResourceMark rm;
2375 _st->print("%-18s ", "KlassAddr");
2376 _st->print("%-4s ", "Size");
2377 _st->print("%-20s ", "State");
2378 _st->print("%-7s ", "Flags");
2379 _st->print("%-5s ", "ClassName");
2380 _st->cr();
2381 }
2382
2383 void PrintClassClosure::do_klass(Klass* k) {
2384 ResourceMark rm;
2385 // klass pointer
2386 _st->print(PTR_FORMAT " ", p2i(k));
2387 // klass size
2388 _st->print("%4d ", k->size());
2389 // initialization state
2390 if (k->is_instance_klass()) {
2391 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2392 } else {
2393 _st->print("%-20s ","");
2394 }
2395 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2396 char buf[10];
2397 int i = 0;
2398 if (k->has_finalizer()) buf[i++] = 'F';
2399 if (k->is_instance_klass()) {
2400 InstanceKlass* ik = InstanceKlass::cast(k);
2401 if (ik->has_final_method()) buf[i++] = 'f';
2402 if (ik->is_rewritten()) buf[i++] = 'W';
2403 if (ik->is_contended()) buf[i++] = 'C';
2404 if (ik->has_been_redefined()) buf[i++] = 'R';
2405 if (ik->is_shared()) buf[i++] = 'S';
2406 }
2407 buf[i++] = '\0';
2408 _st->print("%-7s ", buf);
2409 // klass name
2410 _st->print("%-5s ", k->external_name());
2411 // end
2412 _st->cr();
2413 if (_verbose) {
2414 k->print_on(_st);
2415 }
2416 }
2417
2418 /* jni_id_for for jfieldIds only */
2419 JNIid* InstanceKlass::jni_id_for(int offset) {
2420 MutexLocker ml(JfieldIdCreation_lock);
2421 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2422 if (probe == nullptr) {
2423 // Allocate new static field identifier
2424 probe = new JNIid(this, offset, jni_ids());
2425 set_jni_ids(probe);
2426 }
2427 return probe;
2428 }
2429
2430 u2 InstanceKlass::enclosing_method_data(int offset) const {
2431 const Array<jushort>* const inner_class_list = inner_classes();
2432 if (inner_class_list == nullptr) {
2433 return 0;
2434 }
2435 const int length = inner_class_list->length();
2436 if (length % inner_class_next_offset == 0) {
2437 return 0;
2438 }
2439 const int index = length - enclosing_method_attribute_size;
2440 assert(offset < enclosing_method_attribute_size, "invalid offset");
2441 return inner_class_list->at(index + offset);
2442 }
2443
2444 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2445 u2 method_index) {
2446 Array<jushort>* inner_class_list = inner_classes();
2447 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2448 int length = inner_class_list->length();
2449 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2450 int index = length - enclosing_method_attribute_size;
2451 inner_class_list->at_put(
2452 index + enclosing_method_class_index_offset, class_index);
2453 inner_class_list->at_put(
2454 index + enclosing_method_method_index_offset, method_index);
2455 }
2456 }
2457
2458 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2459 if (method->is_old() && !method->is_obsolete()) {
2460 // If the method passed in is old (but not obsolete), use the current version.
2461 method = method_with_idnum((int)idnum);
2462 assert(method != nullptr, "old and but not obsolete, so should exist");
2463 }
2464 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2465 Atomic::release_store(&jmeths[idnum + 1], new_id);
2466 return new_id;
2467 }
2468
2469 // Lookup or create a jmethodID.
2470 // This code is called by the VMThread and JavaThreads so the
2471 // locking has to be done very carefully to avoid deadlocks
2472 // and/or other cache consistency problems.
2473 //
2474 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2475 Method* method = method_h();
2476 int idnum = method->method_idnum();
2477 jmethodID* jmeths = methods_jmethod_ids_acquire();
2478
2479 // We use a double-check locking idiom here because this cache is
2480 // performance sensitive. In the normal system, this cache only
2481 // transitions from null to non-null which is safe because we use
2482 // release_set_methods_jmethod_ids() to advertise the new cache.
2483 // A partially constructed cache should never be seen by a racing
2484 // thread. We also use release_store() to save a new jmethodID
2485 // in the cache so a partially constructed jmethodID should never be
2486 // seen either. Cache reads of existing jmethodIDs proceed without a
2487 // lock, but cache writes of a new jmethodID requires uniqueness and
2488 // creation of the cache itself requires no leaks so a lock is
2489 // acquired in those two cases.
2490 //
2491 // If the RedefineClasses() API has been used, then this cache grows
2492 // in the redefinition safepoint.
2493
2494 if (jmeths == nullptr) {
2495 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2496 jmeths = methods_jmethod_ids_acquire();
2497 // Still null?
2498 if (jmeths == nullptr) {
2499 size_t size = idnum_allocated_count();
2500 assert(size > (size_t)idnum, "should already have space");
2501 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2502 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2503 // cache size is stored in element[0], other elements offset by one
2504 jmeths[0] = (jmethodID)size;
2505 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2506
2507 // publish jmeths
2508 release_set_methods_jmethod_ids(jmeths);
2509 return new_id;
2510 }
2511 }
2512
2513 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2514 if (id == nullptr) {
2515 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2516 id = jmeths[idnum + 1];
2517 // Still null?
2518 if (id == nullptr) {
2519 return update_jmethod_id(jmeths, method, idnum);
2520 }
2521 }
2522 return id;
2523 }
2524
2525 void InstanceKlass::update_methods_jmethod_cache() {
2526 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2527 jmethodID* cache = _methods_jmethod_ids;
2528 if (cache != nullptr) {
2529 size_t size = idnum_allocated_count();
2530 size_t old_size = (size_t)cache[0];
2531 if (old_size < size + 1) {
2532 // Allocate a larger one and copy entries to the new one.
2533 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2534 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2535 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2536 // The cache size is stored in element[0]; the other elements are offset by one.
2537 new_cache[0] = (jmethodID)size;
2538
2539 for (int i = 1; i <= (int)old_size; i++) {
2540 new_cache[i] = cache[i];
2541 }
2542 _methods_jmethod_ids = new_cache;
2543 FREE_C_HEAP_ARRAY(jmethodID, cache);
2544 }
2545 }
2546 }
2547
2548 // Figure out how many jmethodIDs haven't been allocated, and make
2549 // sure space for them is pre-allocated. This makes getting all
2550 // method ids much, much faster with classes with more than 8
2551 // methods, and has a *substantial* effect on performance with jvmti
2552 // code that loads all jmethodIDs for all classes.
2553 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2554 int new_jmeths = 0;
2555 int length = methods()->length();
2556 for (int index = start_offset; index < length; index++) {
2557 Method* m = methods()->at(index);
2558 jmethodID id = m->find_jmethod_id_or_null();
2559 if (id == nullptr) {
2560 new_jmeths++;
2561 }
2562 }
2563 if (new_jmeths != 0) {
2564 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2565 }
2566 }
2567
2568 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2569 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2570 int idnum = method->method_idnum();
2571 jmethodID* jmeths = methods_jmethod_ids_acquire();
2572 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2573 }
2574
2575 inline DependencyContext InstanceKlass::dependencies() {
2576 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2577 return dep_context;
2578 }
2579
2580 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2581 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2582 }
2583
2584 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2585 assert_lock_strong(CodeCache_lock);
2586 dependencies().add_dependent_nmethod(nm);
2587 }
2588
2589 void InstanceKlass::clean_dependency_context() {
2590 dependencies().clean_unloading_dependents();
2591 }
2592
2593 #ifndef PRODUCT
2594 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2595 dependencies().print_dependent_nmethods(verbose);
2596 }
2597
2598 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2599 return dependencies().is_dependent_nmethod(nm);
2600 }
2601 #endif //PRODUCT
2602
2603 void InstanceKlass::clean_weak_instanceklass_links() {
2604 clean_implementors_list();
2605 clean_method_data();
2606 }
2607
2608 void InstanceKlass::clean_implementors_list() {
2609 assert(is_loader_alive(), "this klass should be live");
2610 if (is_interface()) {
2611 assert (ClassUnloading, "only called for ClassUnloading");
2612 for (;;) {
2613 // Use load_acquire due to competing with inserts
2614 InstanceKlass* volatile* iklass = adr_implementor();
2615 assert(iklass != nullptr, "Klass must not be null");
2616 InstanceKlass* impl = Atomic::load_acquire(iklass);
2617 if (impl != nullptr && !impl->is_loader_alive()) {
2618 // null this field, might be an unloaded instance klass or null
2619 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2620 // Successfully unlinking implementor.
2621 if (log_is_enabled(Trace, class, unload)) {
2622 ResourceMark rm;
2623 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2624 }
2625 return;
2626 }
2627 } else {
2628 return;
2629 }
2630 }
2631 }
2632 }
2633
2634 void InstanceKlass::clean_method_data() {
2635 for (int m = 0; m < methods()->length(); m++) {
2636 MethodData* mdo = methods()->at(m)->method_data();
2637 if (mdo != nullptr) {
2638 mdo->clean_method_data(/*always_clean*/false);
2639 }
2640 }
2641 }
2642
2643 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2644 Klass::metaspace_pointers_do(it);
2645
2646 if (log_is_enabled(Trace, aot)) {
2647 ResourceMark rm;
2648 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2649 }
2650
2651 it->push(&_annotations);
2652 it->push((Klass**)&_array_klasses);
2653 if (!is_rewritten()) {
2654 it->push(&_constants, MetaspaceClosure::_writable);
2655 } else {
2656 it->push(&_constants);
2657 }
2658 it->push(&_inner_classes);
2659 #if INCLUDE_JVMTI
2660 it->push(&_previous_versions);
2661 #endif
2662 #if INCLUDE_CDS
2663 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2664 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2665 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2666 // The length check on the _methods is necessary because classes which don't have any
2667 // methods share the Universe::_the_empty_method_array which is in the RO region.
2668 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2669 // To handle jsr bytecode, new Method* maybe stored into _methods
2670 it->push(&_methods, MetaspaceClosure::_writable);
2671 } else {
2672 #endif
2673 it->push(&_methods);
2674 #if INCLUDE_CDS
2675 }
2676 #endif
2677 it->push(&_default_methods);
2678 it->push(&_local_interfaces);
2679 it->push(&_transitive_interfaces);
2680 it->push(&_method_ordering);
2681 if (!is_rewritten()) {
2682 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2683 } else {
2684 it->push(&_default_vtable_indices);
2685 }
2686
2687 it->push(&_fieldinfo_stream);
2688 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2689 it->push(&_fields_status, MetaspaceClosure::_writable);
2690
2691 if (itable_length() > 0) {
2692 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2693 int method_table_offset_in_words = ioe->offset()/wordSize;
2694 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2695
2696 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2697 / itableOffsetEntry::size();
2698
2699 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2700 if (ioe->interface_klass() != nullptr) {
2701 it->push(ioe->interface_klass_addr());
2702 itableMethodEntry* ime = ioe->first_method_entry(this);
2703 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2704 for (int index = 0; index < n; index ++) {
2705 it->push(ime[index].method_addr());
2706 }
2707 }
2708 }
2709 }
2710
2711 it->push(&_nest_host);
2712 it->push(&_nest_members);
2713 it->push(&_permitted_subclasses);
2714 it->push(&_record_components);
2715 }
2716
2717 #if INCLUDE_CDS
2718 void InstanceKlass::remove_unshareable_info() {
2719 if (is_linked()) {
2720 assert(can_be_verified_at_dumptime(), "must be");
2721 // Remember this so we can avoid walking the hierarchy at runtime.
2722 set_verified_at_dump_time();
2723 }
2724 _misc_flags.set_has_init_deps_processed(false);
2725
2726 _misc_flags.set_has_init_deps_processed(false);
2727
2728 Klass::remove_unshareable_info();
2729
2730 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2731 // Classes are attempted to link during dumping and may fail,
2732 // but these classes are still in the dictionary and class list in CLD.
2733 // If the class has failed verification, there is nothing else to remove.
2734 return;
2735 }
2736
2737 // Reset to the 'allocated' state to prevent any premature accessing to
2738 // a shared class at runtime while the class is still being loaded and
2739 // restored. A class' init_state is set to 'loaded' at runtime when it's
2740 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2741 _init_state = allocated;
2742
2743 { // Otherwise this needs to take out the Compile_lock.
2744 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2745 init_implementor();
2746 }
2747
2748 // Call remove_unshareable_info() on other objects that belong to this class, except
2749 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2750 // ArchiveBuilder::make_klasses_shareable(),
2751
2752 for (int i = 0; i < methods()->length(); i++) {
2753 Method* m = methods()->at(i);
2754 m->remove_unshareable_info();
2755 }
2756
2757 // do array classes also.
2758 if (array_klasses() != nullptr) {
2759 array_klasses()->remove_unshareable_info();
2760 }
2761
2762 // These are not allocated from metaspace. They are safe to set to null.
2763 _source_debug_extension = nullptr;
2764 _dep_context = nullptr;
2765 _osr_nmethods_head = nullptr;
2766 #if INCLUDE_JVMTI
2767 _breakpoints = nullptr;
2768 _previous_versions = nullptr;
2769 _cached_class_file = nullptr;
2770 _jvmti_cached_class_field_map = nullptr;
2771 #endif
2772
2773 _init_thread = nullptr;
2774 _methods_jmethod_ids = nullptr;
2775 _jni_ids = nullptr;
2776 _oop_map_cache = nullptr;
2777 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2778 // keep _nest_host
2779 } else {
2780 // clear _nest_host to ensure re-load at runtime
2781 _nest_host = nullptr;
2782 }
2783 init_shared_package_entry();
2784 _dep_context_last_cleaned = 0;
2785 DEBUG_ONLY(_shared_class_load_count = 0);
2786
2787 remove_unshareable_flags();
2788 }
2789
2790 void InstanceKlass::remove_unshareable_flags() {
2791 // clear all the flags/stats that shouldn't be in the archived version
2792 assert(!is_scratch_class(), "must be");
2793 assert(!has_been_redefined(), "must be");
2794 #if INCLUDE_JVMTI
2795 set_is_being_redefined(false);
2796 #endif
2797 set_has_resolved_methods(false);
2798 }
2799
2800 void InstanceKlass::remove_java_mirror() {
2801 Klass::remove_java_mirror();
2802
2803 // do array classes also.
2804 if (array_klasses() != nullptr) {
2805 array_klasses()->remove_java_mirror();
2806 }
2807 }
2808
2809 void InstanceKlass::init_shared_package_entry() {
2810 assert(CDSConfig::is_dumping_archive(), "must be");
2811 #if !INCLUDE_CDS_JAVA_HEAP
2812 _package_entry = nullptr;
2813 #else
2814 if (CDSConfig::is_dumping_full_module_graph()) {
2815 if (defined_by_other_loaders()) {
2816 _package_entry = nullptr;
2817 } else {
2818 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2819 }
2820 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2821 CDSConfig::is_using_full_module_graph() &&
2822 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2823 // _package_entry is an archived package in the base archive. Leave it as is.
2824 } else {
2825 _package_entry = nullptr;
2826 }
2827 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2828 #endif
2829 }
2830
2831 void InstanceKlass::compute_has_loops_flag_for_methods() {
2832 Array<Method*>* methods = this->methods();
2833 for (int index = 0; index < methods->length(); ++index) {
2834 Method* m = methods->at(index);
2835 if (!m->is_overpass()) { // work around JDK-8305771
2836 m->compute_has_loops_flag();
2837 }
2838 }
2839 }
2840
2841 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2842 PackageEntry* pkg_entry, TRAPS) {
2843 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2844 // before the InstanceKlass is added to the SystemDictionary. Make
2845 // sure the current state is <loaded.
2846 assert(!is_loaded(), "invalid init state");
2847 assert(!shared_loading_failed(), "Must not try to load failed class again");
2848 set_package(loader_data, pkg_entry, CHECK);
2849 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2850
2851 Array<Method*>* methods = this->methods();
2852 int num_methods = methods->length();
2853 for (int index = 0; index < num_methods; ++index) {
2854 methods->at(index)->restore_unshareable_info(CHECK);
2855 }
2856 #if INCLUDE_JVMTI
2857 if (JvmtiExport::has_redefined_a_class()) {
2858 // Reinitialize vtable because RedefineClasses may have changed some
2859 // entries in this vtable for super classes so the CDS vtable might
2860 // point to old or obsolete entries. RedefineClasses doesn't fix up
2861 // vtables in the shared system dictionary, only the main one.
2862 // It also redefines the itable too so fix that too.
2863 // First fix any default methods that point to a super class that may
2864 // have been redefined.
2865 bool trace_name_printed = false;
2866 adjust_default_methods(&trace_name_printed);
2867 if (verified_at_dump_time()) {
2868 // Initialize vtable and itable for classes which can be verified at dump time.
2869 // Unlinked classes such as old classes with major version < 50 cannot be verified
2870 // at dump time.
2871 vtable().initialize_vtable();
2872 itable().initialize_itable();
2873 }
2874 }
2875 #endif // INCLUDE_JVMTI
2876
2877 // restore constant pool resolved references
2878 constants()->restore_unshareable_info(CHECK);
2879
2880 if (array_klasses() != nullptr) {
2881 // To get a consistent list of classes we need MultiArray_lock to ensure
2882 // array classes aren't observed while they are being restored.
2883 RecursiveLocker rl(MultiArray_lock, THREAD);
2884 assert(this == array_klasses()->bottom_klass(), "sanity");
2885 // Array classes have null protection domain.
2886 // --> see ArrayKlass::complete_create_array_klass()
2887 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2888 }
2889
2890 // Initialize @ValueBased class annotation if not already set in the archived klass.
2891 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2892 set_is_value_based();
2893 }
2894 }
2895
2896 bool InstanceKlass::can_be_verified_at_dumptime() const {
2897 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2898 return true;
2899 }
2900
2901 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2902 // This is a class that was dumped into the base archive, so we know
2903 // it was verified at dump time.
2904 return true;
2905 }
2906
2907 // Check if a class or any of its supertypes has a version older than 50.
2908 // CDS will not perform verification of old classes during dump time because
2909 // without changing the old verifier, the verification constraint cannot be
2910 // retrieved during dump time.
2911 // Verification of archived old classes will be performed during run time.
2912 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2913 return false;
2914 }
2915 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2916 return false;
2917 }
2918 Array<InstanceKlass*>* interfaces = local_interfaces();
2919 int len = interfaces->length();
2920 for (int i = 0; i < len; i++) {
2921 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2922 return false;
2923 }
2924 }
2925 return true;
2926 }
2927
2928 #endif // INCLUDE_CDS
2929
2930 #if INCLUDE_JVMTI
2931 static void clear_all_breakpoints(Method* m) {
2932 m->clear_all_breakpoints();
2933 }
2934 #endif
2935
2936 void InstanceKlass::unload_class(InstanceKlass* ik) {
2937
2938 if (ik->is_scratch_class()) {
2939 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2940 return;
2941 }
2942 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2943
2944 // Release dependencies.
2945 ik->dependencies().remove_all_dependents();
2946
2947 // notify the debugger
2948 if (JvmtiExport::should_post_class_unload()) {
2949 JvmtiExport::post_class_unload(ik);
2950 }
2951
2952 // notify ClassLoadingService of class unload
2953 ClassLoadingService::notify_class_unloaded(ik);
2954
2955 SystemDictionaryShared::handle_class_unloading(ik);
2956
2957 if (log_is_enabled(Info, class, unload)) {
2958 ResourceMark rm;
2959 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2960 }
2961
2962 Events::log_class_unloading(Thread::current(), ik);
2963
2964 #if INCLUDE_JFR
2965 assert(ik != nullptr, "invariant");
2966 EventClassUnload event;
2967 event.set_unloadedClass(ik);
2968 event.set_definingClassLoader(ik->class_loader_data());
2969 event.commit();
2970 #endif
2971 }
2972
2973 static void method_release_C_heap_structures(Method* m) {
2974 m->release_C_heap_structures();
2975 }
2976
2977 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2978 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2979 // Clean up C heap
2980 Klass::release_C_heap_structures();
2981
2982 // Deallocate and call destructors for MDO mutexes
2983 if (release_sub_metadata) {
2984 methods_do(method_release_C_heap_structures);
2985 }
2986
2987 // Deallocate oop map cache
2988 if (_oop_map_cache != nullptr) {
2989 delete _oop_map_cache;
2990 _oop_map_cache = nullptr;
2991 }
2992
2993 // Deallocate JNI identifiers for jfieldIDs
2994 JNIid::deallocate(jni_ids());
2995 set_jni_ids(nullptr);
2996
2997 jmethodID* jmeths = methods_jmethod_ids_acquire();
2998 if (jmeths != nullptr) {
2999 release_set_methods_jmethod_ids(nullptr);
3000 FreeHeap(jmeths);
3001 }
3002
3003 assert(_dep_context == nullptr,
3004 "dependencies should already be cleaned");
3005
3006 #if INCLUDE_JVMTI
3007 // Deallocate breakpoint records
3008 if (breakpoints() != nullptr) {
3009 methods_do(clear_all_breakpoints);
3010 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3011 }
3012
3013 // deallocate the cached class file
3014 if (_cached_class_file != nullptr) {
3015 os::free(_cached_class_file);
3016 _cached_class_file = nullptr;
3017 }
3018 #endif
3019
3020 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3021
3022 if (release_sub_metadata) {
3023 constants()->release_C_heap_structures();
3024 }
3025 }
3026
3027 // The constant pool is on stack if any of the methods are executing or
3028 // referenced by handles.
3029 bool InstanceKlass::on_stack() const {
3030 return _constants->on_stack();
3031 }
3032
3033 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3034 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3035 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3036
3037 // minor and major version numbers of class file
3038 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3039 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3040 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3041 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3042
3043 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3044 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3045 if (ik->constants()->version() == version) {
3046 return ik;
3047 }
3048 }
3049 return nullptr;
3050 }
3051
3052 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3053 if (array == nullptr) {
3054 _source_debug_extension = nullptr;
3055 } else {
3056 // Adding one to the attribute length in order to store a null terminator
3057 // character could cause an overflow because the attribute length is
3058 // already coded with an u4 in the classfile, but in practice, it's
3059 // unlikely to happen.
3060 assert((length+1) > length, "Overflow checking");
3061 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3062 for (int i = 0; i < length; i++) {
3063 sde[i] = array[i];
3064 }
3065 sde[length] = '\0';
3066 _source_debug_extension = sde;
3067 }
3068 }
3069
3070 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3071 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3072 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3073
3074 const char* InstanceKlass::signature_name() const {
3075
3076 // Get the internal name as a c string
3077 const char* src = (const char*) (name()->as_C_string());
3078 const int src_length = (int)strlen(src);
3079
3080 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3081
3082 // Add L as type indicator
3083 int dest_index = 0;
3084 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3085
3086 // Add the actual class name
3087 for (int src_index = 0; src_index < src_length; ) {
3088 dest[dest_index++] = src[src_index++];
3089 }
3090
3091 if (is_hidden()) { // Replace the last '+' with a '.'.
3092 for (int index = (int)src_length; index > 0; index--) {
3093 if (dest[index] == '+') {
3094 dest[index] = JVM_SIGNATURE_DOT;
3095 break;
3096 }
3097 }
3098 }
3099
3100 // Add the semicolon and the null
3101 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3102 dest[dest_index] = '\0';
3103 return dest;
3104 }
3105
3106 ModuleEntry* InstanceKlass::module() const {
3107 if (is_hidden() &&
3108 in_unnamed_package() &&
3109 class_loader_data()->has_class_mirror_holder()) {
3110 // For a non-strong hidden class defined to an unnamed package,
3111 // its (class held) CLD will not have an unnamed module created for it.
3112 // Two choices to find the correct ModuleEntry:
3113 // 1. If hidden class is within a nest, use nest host's module
3114 // 2. Find the unnamed module off from the class loader
3115 // For now option #2 is used since a nest host is not set until
3116 // after the instance class is created in jvm_lookup_define_class().
3117 if (class_loader_data()->is_boot_class_loader_data()) {
3118 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3119 } else {
3120 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3121 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3122 return java_lang_Module::module_entry(module);
3123 }
3124 }
3125
3126 // Class is in a named package
3127 if (!in_unnamed_package()) {
3128 return _package_entry->module();
3129 }
3130
3131 // Class is in an unnamed package, return its loader's unnamed module
3132 return class_loader_data()->unnamed_module();
3133 }
3134
3135 bool InstanceKlass::in_javabase_module() const {
3136 return module()->name() == vmSymbols::java_base();
3137 }
3138
3139 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3140
3141 // ensure java/ packages only loaded by boot or platform builtin loaders
3142 // not needed for shared class since CDS does not archive prohibited classes.
3143 if (!is_shared()) {
3144 check_prohibited_package(name(), loader_data, CHECK);
3145 }
3146
3147 if (is_shared() && _package_entry != nullptr) {
3148 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3149 // we can use the saved package
3150 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3151 return;
3152 } else {
3153 _package_entry = nullptr;
3154 }
3155 }
3156
3157 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3158 // it returns, so we need to decrement it when the current function exits.
3159 TempNewSymbol from_class_name =
3160 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3161
3162 Symbol* pkg_name;
3163 if (pkg_entry != nullptr) {
3164 pkg_name = pkg_entry->name();
3165 } else {
3166 pkg_name = from_class_name;
3167 }
3168
3169 if (pkg_name != nullptr && loader_data != nullptr) {
3170
3171 // Find in class loader's package entry table.
3172 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3173
3174 // If the package name is not found in the loader's package
3175 // entry table, it is an indication that the package has not
3176 // been defined. Consider it defined within the unnamed module.
3177 if (_package_entry == nullptr) {
3178
3179 if (!ModuleEntryTable::javabase_defined()) {
3180 // Before java.base is defined during bootstrapping, define all packages in
3181 // the java.base module. If a non-java.base package is erroneously placed
3182 // in the java.base module it will be caught later when java.base
3183 // is defined by ModuleEntryTable::verify_javabase_packages check.
3184 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3185 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3186 } else {
3187 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3188 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3189 }
3190
3191 // A package should have been successfully created
3192 DEBUG_ONLY(ResourceMark rm(THREAD));
3193 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3194 name()->as_C_string(), loader_data->loader_name_and_id());
3195 }
3196
3197 if (log_is_enabled(Debug, module)) {
3198 ResourceMark rm(THREAD);
3199 ModuleEntry* m = _package_entry->module();
3200 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3201 external_name(),
3202 pkg_name->as_C_string(),
3203 loader_data->loader_name_and_id(),
3204 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3205 }
3206 } else {
3207 ResourceMark rm(THREAD);
3208 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3209 external_name(),
3210 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3211 UNNAMED_MODULE);
3212 }
3213 }
3214
3215 // Function set_classpath_index ensures that for a non-null _package_entry
3216 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3217 // It then sets the classpath_index in the package entry record.
3218 //
3219 // The classpath_index field is used to find the entry on the boot loader class
3220 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3221 // in an unnamed module. It is also used to indicate (for all packages whose
3222 // classes are loaded by the boot loader) that at least one of the package's
3223 // classes has been loaded.
3224 void InstanceKlass::set_classpath_index(s2 path_index) {
3225 if (_package_entry != nullptr) {
3226 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3227 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3228 assert(path_index != -1, "Unexpected classpath_index");
3229 _package_entry->set_classpath_index(path_index);
3230 }
3231 }
3232
3233 // different versions of is_same_class_package
3234
3235 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3236 oop classloader1 = this->class_loader();
3237 PackageEntry* classpkg1 = this->package();
3238 if (class2->is_objArray_klass()) {
3239 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3240 }
3241
3242 oop classloader2;
3243 PackageEntry* classpkg2;
3244 if (class2->is_instance_klass()) {
3245 classloader2 = class2->class_loader();
3246 classpkg2 = class2->package();
3247 } else {
3248 assert(class2->is_typeArray_klass(), "should be type array");
3249 classloader2 = nullptr;
3250 classpkg2 = nullptr;
3251 }
3252
3253 // Same package is determined by comparing class loader
3254 // and package entries. Both must be the same. This rule
3255 // applies even to classes that are defined in the unnamed
3256 // package, they still must have the same class loader.
3257 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3258 return true;
3259 }
3260
3261 return false;
3262 }
3263
3264 // return true if this class and other_class are in the same package. Classloader
3265 // and classname information is enough to determine a class's package
3266 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3267 const Symbol* other_class_name) const {
3268 if (class_loader() != other_class_loader) {
3269 return false;
3270 }
3271 if (name()->fast_compare(other_class_name) == 0) {
3272 return true;
3273 }
3274
3275 {
3276 ResourceMark rm;
3277
3278 bool bad_class_name = false;
3279 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3280 if (bad_class_name) {
3281 return false;
3282 }
3283 // Check that package_from_class_name() returns null, not "", if there is no package.
3284 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3285
3286 const Symbol* const this_package_name =
3287 this->package() != nullptr ? this->package()->name() : nullptr;
3288
3289 if (this_package_name == nullptr || other_pkg == nullptr) {
3290 // One of the two doesn't have a package. Only return true if the other
3291 // one also doesn't have a package.
3292 return this_package_name == other_pkg;
3293 }
3294
3295 // Check if package is identical
3296 return this_package_name->fast_compare(other_pkg) == 0;
3297 }
3298 }
3299
3300 static bool is_prohibited_package_slow(Symbol* class_name) {
3301 // Caller has ResourceMark
3302 int length;
3303 jchar* unicode = class_name->as_unicode(length);
3304 return (length >= 5 &&
3305 unicode[0] == 'j' &&
3306 unicode[1] == 'a' &&
3307 unicode[2] == 'v' &&
3308 unicode[3] == 'a' &&
3309 unicode[4] == '/');
3310 }
3311
3312 // Only boot and platform class loaders can define classes in "java/" packages.
3313 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3314 ClassLoaderData* loader_data,
3315 TRAPS) {
3316 if (!loader_data->is_boot_class_loader_data() &&
3317 !loader_data->is_platform_class_loader_data() &&
3318 class_name != nullptr && class_name->utf8_length() >= 5) {
3319 ResourceMark rm(THREAD);
3320 bool prohibited;
3321 const u1* base = class_name->base();
3322 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3323 prohibited = is_prohibited_package_slow(class_name);
3324 } else {
3325 char* name = class_name->as_C_string();
3326 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3327 }
3328 if (prohibited) {
3329 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3330 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3331 char* name = pkg_name->as_C_string();
3332 const char* class_loader_name = loader_data->loader_name_and_id();
3333 StringUtils::replace_no_expand(name, "/", ".");
3334 const char* msg_text1 = "Class loader (instance of): ";
3335 const char* msg_text2 = " tried to load prohibited package name: ";
3336 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3337 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3338 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3339 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3340 }
3341 }
3342 return;
3343 }
3344
3345 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3346 constantPoolHandle i_cp(THREAD, constants());
3347 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3348 int ioff = iter.inner_class_info_index();
3349 if (ioff != 0) {
3350 // Check to see if the name matches the class we're looking for
3351 // before attempting to find the class.
3352 if (i_cp->klass_name_at_matches(this, ioff)) {
3353 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3354 if (this == inner_klass) {
3355 *ooff = iter.outer_class_info_index();
3356 *noff = iter.inner_name_index();
3357 return true;
3358 }
3359 }
3360 }
3361 }
3362 return false;
3363 }
3364
3365 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3366 InstanceKlass* outer_klass = nullptr;
3367 *inner_is_member = false;
3368 int ooff = 0, noff = 0;
3369 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3370 if (has_inner_classes_attr) {
3371 constantPoolHandle i_cp(THREAD, constants());
3372 if (ooff != 0) {
3373 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3374 if (!ok->is_instance_klass()) {
3375 // If the outer class is not an instance klass then it cannot have
3376 // declared any inner classes.
3377 ResourceMark rm(THREAD);
3378 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3379 Exceptions::fthrow(
3380 THREAD_AND_LOCATION,
3381 vmSymbols::java_lang_IncompatibleClassChangeError(),
3382 "%s and %s disagree on InnerClasses attribute",
3383 ok->external_name(),
3384 external_name());
3385 return nullptr;
3386 }
3387 outer_klass = InstanceKlass::cast(ok);
3388 *inner_is_member = true;
3389 }
3390 if (nullptr == outer_klass) {
3391 // It may be a local class; try for that.
3392 int encl_method_class_idx = enclosing_method_class_index();
3393 if (encl_method_class_idx != 0) {
3394 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3395 outer_klass = InstanceKlass::cast(ok);
3396 *inner_is_member = false;
3397 }
3398 }
3399 }
3400
3401 // If no inner class attribute found for this class.
3402 if (nullptr == outer_klass) return nullptr;
3403
3404 // Throws an exception if outer klass has not declared k as an inner klass
3405 // We need evidence that each klass knows about the other, or else
3406 // the system could allow a spoof of an inner class to gain access rights.
3407 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3408 return outer_klass;
3409 }
3410
3411 u2 InstanceKlass::compute_modifier_flags() const {
3412 u2 access = access_flags().as_unsigned_short();
3413
3414 // But check if it happens to be member class.
3415 InnerClassesIterator iter(this);
3416 for (; !iter.done(); iter.next()) {
3417 int ioff = iter.inner_class_info_index();
3418 // Inner class attribute can be zero, skip it.
3419 // Strange but true: JVM spec. allows null inner class refs.
3420 if (ioff == 0) continue;
3421
3422 // only look at classes that are already loaded
3423 // since we are looking for the flags for our self.
3424 Symbol* inner_name = constants()->klass_name_at(ioff);
3425 if (name() == inner_name) {
3426 // This is really a member class.
3427 access = iter.inner_access_flags();
3428 break;
3429 }
3430 }
3431 // Remember to strip ACC_SUPER bit
3432 return (access & (~JVM_ACC_SUPER));
3433 }
3434
3435 jint InstanceKlass::jvmti_class_status() const {
3436 jint result = 0;
3437
3438 if (is_linked()) {
3439 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3440 }
3441
3442 if (is_initialized()) {
3443 assert(is_linked(), "Class status is not consistent");
3444 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3445 }
3446 if (is_in_error_state()) {
3447 result |= JVMTI_CLASS_STATUS_ERROR;
3448 }
3449 return result;
3450 }
3451
3452 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3453 bool implements_interface; // initialized by method_at_itable_or_null
3454 Method* m = method_at_itable_or_null(holder, index,
3455 implements_interface); // out parameter
3456 if (m != nullptr) {
3457 assert(implements_interface, "sanity");
3458 return m;
3459 } else if (implements_interface) {
3460 // Throw AbstractMethodError since corresponding itable slot is empty.
3461 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3462 } else {
3463 // If the interface isn't implemented by the receiver class,
3464 // the VM should throw IncompatibleClassChangeError.
3465 ResourceMark rm(THREAD);
3466 stringStream ss;
3467 bool same_module = (module() == holder->module());
3468 ss.print("Receiver class %s does not implement "
3469 "the interface %s defining the method to be called "
3470 "(%s%s%s)",
3471 external_name(), holder->external_name(),
3472 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3473 (same_module) ? "" : "; ",
3474 (same_module) ? "" : holder->class_in_module_of_loader());
3475 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3476 }
3477 }
3478
3479 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3480 klassItable itable(this);
3481 for (int i = 0; i < itable.size_offset_table(); i++) {
3482 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3483 if (offset_entry->interface_klass() == holder) {
3484 implements_interface = true;
3485 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3486 Method* m = ime[index].method();
3487 return m;
3488 }
3489 }
3490 implements_interface = false;
3491 return nullptr; // offset entry not found
3492 }
3493
3494 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3495 assert(is_linked(), "required");
3496 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3497 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3498
3499 int vtable_index = Method::invalid_vtable_index;
3500 Symbol* name = intf_method->name();
3501 Symbol* signature = intf_method->signature();
3502
3503 // First check in default method array
3504 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3505 int index = find_method_index(default_methods(),
3506 name, signature,
3507 Klass::OverpassLookupMode::find,
3508 Klass::StaticLookupMode::find,
3509 Klass::PrivateLookupMode::find);
3510 if (index >= 0) {
3511 vtable_index = default_vtable_indices()->at(index);
3512 }
3513 }
3514 if (vtable_index == Method::invalid_vtable_index) {
3515 // get vtable_index for miranda methods
3516 klassVtable vt = vtable();
3517 vtable_index = vt.index_of_miranda(name, signature);
3518 }
3519 return vtable_index;
3520 }
3521
3522 #if INCLUDE_JVMTI
3523 // update default_methods for redefineclasses for methods that are
3524 // not yet in the vtable due to concurrent subclass define and superinterface
3525 // redefinition
3526 // Note: those in the vtable, should have been updated via adjust_method_entries
3527 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3528 // search the default_methods for uses of either obsolete or EMCP methods
3529 if (default_methods() != nullptr) {
3530 for (int index = 0; index < default_methods()->length(); index ++) {
3531 Method* old_method = default_methods()->at(index);
3532 if (old_method == nullptr || !old_method->is_old()) {
3533 continue; // skip uninteresting entries
3534 }
3535 assert(!old_method->is_deleted(), "default methods may not be deleted");
3536 Method* new_method = old_method->get_new_method();
3537 default_methods()->at_put(index, new_method);
3538
3539 if (log_is_enabled(Info, redefine, class, update)) {
3540 ResourceMark rm;
3541 if (!(*trace_name_printed)) {
3542 log_info(redefine, class, update)
3543 ("adjust: klassname=%s default methods from name=%s",
3544 external_name(), old_method->method_holder()->external_name());
3545 *trace_name_printed = true;
3546 }
3547 log_debug(redefine, class, update, vtables)
3548 ("default method update: %s(%s) ",
3549 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3550 }
3551 }
3552 }
3553 }
3554 #endif // INCLUDE_JVMTI
3555
3556 // On-stack replacement stuff
3557 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3558 assert_lock_strong(NMethodState_lock);
3559 #ifndef PRODUCT
3560 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3561 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3562 "redundant OSR recompilation detected. memory leak in CodeCache!");
3563 #endif
3564 // only one compilation can be active
3565 assert(n->is_osr_method(), "wrong kind of nmethod");
3566 n->set_osr_link(osr_nmethods_head());
3567 set_osr_nmethods_head(n);
3568 // Raise the highest osr level if necessary
3569 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3570
3571 // Get rid of the osr methods for the same bci that have lower levels.
3572 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3573 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3574 if (inv != nullptr && inv->is_in_use()) {
3575 inv->make_not_entrant("OSR invalidation of lower levels");
3576 }
3577 }
3578 }
3579
3580 // Remove osr nmethod from the list. Return true if found and removed.
3581 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3582 // This is a short non-blocking critical region, so the no safepoint check is ok.
3583 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3584 assert(n->is_osr_method(), "wrong kind of nmethod");
3585 nmethod* last = nullptr;
3586 nmethod* cur = osr_nmethods_head();
3587 int max_level = CompLevel_none; // Find the max comp level excluding n
3588 Method* m = n->method();
3589 // Search for match
3590 bool found = false;
3591 while(cur != nullptr && cur != n) {
3592 if (m == cur->method()) {
3593 // Find max level before n
3594 max_level = MAX2(max_level, cur->comp_level());
3595 }
3596 last = cur;
3597 cur = cur->osr_link();
3598 }
3599 nmethod* next = nullptr;
3600 if (cur == n) {
3601 found = true;
3602 next = cur->osr_link();
3603 if (last == nullptr) {
3604 // Remove first element
3605 set_osr_nmethods_head(next);
3606 } else {
3607 last->set_osr_link(next);
3608 }
3609 }
3610 n->set_osr_link(nullptr);
3611 cur = next;
3612 while (cur != nullptr) {
3613 // Find max level after n
3614 if (m == cur->method()) {
3615 max_level = MAX2(max_level, cur->comp_level());
3616 }
3617 cur = cur->osr_link();
3618 }
3619 m->set_highest_osr_comp_level(max_level);
3620 return found;
3621 }
3622
3623 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3624 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3625 nmethod* osr = osr_nmethods_head();
3626 int found = 0;
3627 while (osr != nullptr) {
3628 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3629 if (osr->method() == m) {
3630 deopt_scope->mark(osr);
3631 found++;
3632 }
3633 osr = osr->osr_link();
3634 }
3635 return found;
3636 }
3637
3638 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3639 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3640 nmethod* osr = osr_nmethods_head();
3641 nmethod* best = nullptr;
3642 while (osr != nullptr) {
3643 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3644 // There can be a time when a c1 osr method exists but we are waiting
3645 // for a c2 version. When c2 completes its osr nmethod we will trash
3646 // the c1 version and only be able to find the c2 version. However
3647 // while we overflow in the c1 code at back branches we don't want to
3648 // try and switch to the same code as we are already running
3649
3650 if (osr->method() == m &&
3651 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3652 if (match_level) {
3653 if (osr->comp_level() == comp_level) {
3654 // Found a match - return it.
3655 return osr;
3656 }
3657 } else {
3658 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3659 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3660 // Found the best possible - return it.
3661 return osr;
3662 }
3663 best = osr;
3664 }
3665 }
3666 }
3667 osr = osr->osr_link();
3668 }
3669
3670 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3671 if (best != nullptr && best->comp_level() >= comp_level) {
3672 return best;
3673 }
3674 return nullptr;
3675 }
3676
3677 // -----------------------------------------------------------------------------------------------------
3678 // Printing
3679
3680 #define BULLET " - "
3681
3682 static const char* state_names[] = {
3683 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3684 };
3685
3686 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3687 for (int i = 0; i < len; i++) {
3688 intptr_t e = start[i];
3689 st->print("%d : " INTPTR_FORMAT, i, e);
3690 if (MetaspaceObj::is_valid((Metadata*)e)) {
3691 st->print(" ");
3692 ((Metadata*)e)->print_value_on(st);
3693 }
3694 st->cr();
3695 }
3696 }
3697
3698 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3699 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3700 }
3701
3702 const char* InstanceKlass::init_state_name() const {
3703 return state_names[init_state()];
3704 }
3705
3706 const char* InstanceKlass::state2name(ClassState s) {
3707 return state_names[s];
3708 }
3709
3710 void InstanceKlass::print_on(outputStream* st) const {
3711 assert(is_klass(), "must be klass");
3712 Klass::print_on(st);
3713
3714 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3715 st->print(BULLET"klass size: %d", size()); st->cr();
3716 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3717 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3718 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3719 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3720 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3721 st->print(BULLET"sub: ");
3722 Klass* sub = subklass();
3723 int n;
3724 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3725 if (n < MaxSubklassPrintSize) {
3726 sub->print_value_on(st);
3727 st->print(" ");
3728 }
3729 }
3730 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3731 st->cr();
3732
3733 if (is_interface()) {
3734 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3735 if (nof_implementors() == 1) {
3736 st->print_cr(BULLET"implementor: ");
3737 st->print(" ");
3738 implementor()->print_value_on(st);
3739 st->cr();
3740 }
3741 }
3742
3743 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3744 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3745 if (Verbose || WizardMode) {
3746 Array<Method*>* method_array = methods();
3747 for (int i = 0; i < method_array->length(); i++) {
3748 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3749 }
3750 }
3751 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3752 if (default_methods() != nullptr) {
3753 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3754 if (Verbose) {
3755 Array<Method*>* method_array = default_methods();
3756 for (int i = 0; i < method_array->length(); i++) {
3757 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3758 }
3759 }
3760 }
3761 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3762 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3763 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3764
3765 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3766
3767 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3768 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3769
3770 if (secondary_supers() != nullptr) {
3771 if (Verbose) {
3772 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3773 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3774 for (int i = 0; i < _secondary_supers->length(); i++) {
3775 ResourceMark rm; // for external_name()
3776 Klass* secondary_super = _secondary_supers->at(i);
3777 st->print(BULLET"%2d:", i);
3778 if (is_hashed) {
3779 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3780 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3781 st->print(" dist:%02d:", distance);
3782 }
3783 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3784 }
3785 }
3786 }
3787 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3788
3789 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3790 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3791 if (source_debug_extension() != nullptr) {
3792 st->print(BULLET"source debug extension: ");
3793 st->print("%s", source_debug_extension());
3794 st->cr();
3795 }
3796 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3797 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3798 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3799 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3800 {
3801 bool have_pv = false;
3802 // previous versions are linked together through the InstanceKlass
3803 for (InstanceKlass* pv_node = previous_versions();
3804 pv_node != nullptr;
3805 pv_node = pv_node->previous_versions()) {
3806 if (!have_pv)
3807 st->print(BULLET"previous version: ");
3808 have_pv = true;
3809 pv_node->constants()->print_value_on(st);
3810 }
3811 if (have_pv) st->cr();
3812 }
3813
3814 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3815 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3816 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3817 print_on_maybe_null(st, BULLET"record components: ", record_components());
3818 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3819 if (java_mirror() != nullptr) {
3820 st->print(BULLET"java mirror: ");
3821 java_mirror()->print_value_on(st);
3822 st->cr();
3823 } else {
3824 st->print_cr(BULLET"java mirror: null");
3825 }
3826 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3827 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3828 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3829 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3830 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3831
3832 FieldPrinter print_static_field(st);
3833 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3834 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3835 FieldPrinter print_nonstatic_field(st);
3836 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3837 ik->print_nonstatic_fields(&print_nonstatic_field);
3838
3839 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3840 OopMapBlock* map = start_of_nonstatic_oop_maps();
3841 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3842 while (map < end_map) {
3843 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3844 map++;
3845 }
3846 st->cr();
3847 }
3848
3849 void InstanceKlass::print_value_on(outputStream* st) const {
3850 assert(is_klass(), "must be klass");
3851 if (Verbose || WizardMode) access_flags().print_on(st);
3852 name()->print_value_on(st);
3853 }
3854
3855 void FieldPrinter::do_field(fieldDescriptor* fd) {
3856 _st->print(BULLET);
3857 if (_obj == nullptr) {
3858 fd->print_on(_st);
3859 _st->cr();
3860 } else {
3861 fd->print_on_for(_st, _obj);
3862 _st->cr();
3863 }
3864 }
3865
3866
3867 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3868 Klass::oop_print_on(obj, st);
3869
3870 if (this == vmClasses::String_klass()) {
3871 typeArrayOop value = java_lang_String::value(obj);
3872 juint length = java_lang_String::length(obj);
3873 if (value != nullptr &&
3874 value->is_typeArray() &&
3875 length <= (juint) value->length()) {
3876 st->print(BULLET"string: ");
3877 java_lang_String::print(obj, st);
3878 st->cr();
3879 }
3880 }
3881
3882 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3883 FieldPrinter print_field(st, obj);
3884 print_nonstatic_fields(&print_field);
3885
3886 if (this == vmClasses::Class_klass()) {
3887 st->print(BULLET"signature: ");
3888 java_lang_Class::print_signature(obj, st);
3889 st->cr();
3890 Klass* real_klass = java_lang_Class::as_Klass(obj);
3891 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3892 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3893 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3894 }
3895 } else if (this == vmClasses::MethodType_klass()) {
3896 st->print(BULLET"signature: ");
3897 java_lang_invoke_MethodType::print_signature(obj, st);
3898 st->cr();
3899 }
3900 }
3901
3902 #ifndef PRODUCT
3903
3904 bool InstanceKlass::verify_itable_index(int i) {
3905 int method_count = klassItable::method_count_for_interface(this);
3906 assert(i >= 0 && i < method_count, "index out of bounds");
3907 return true;
3908 }
3909
3910 #endif //PRODUCT
3911
3912 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3913 st->print("a ");
3914 name()->print_value_on(st);
3915 obj->print_address_on(st);
3916 if (this == vmClasses::String_klass()
3917 && java_lang_String::value(obj) != nullptr) {
3918 ResourceMark rm;
3919 int len = java_lang_String::length(obj);
3920 int plen = (len < 24 ? len : 12);
3921 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3922 st->print(" = \"%s\"", str);
3923 if (len > plen)
3924 st->print("...[%d]", len);
3925 } else if (this == vmClasses::Class_klass()) {
3926 Klass* k = java_lang_Class::as_Klass(obj);
3927 st->print(" = ");
3928 if (k != nullptr) {
3929 k->print_value_on(st);
3930 } else {
3931 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3932 st->print("%s", tname ? tname : "type?");
3933 }
3934 } else if (this == vmClasses::MethodType_klass()) {
3935 st->print(" = ");
3936 java_lang_invoke_MethodType::print_signature(obj, st);
3937 } else if (java_lang_boxing_object::is_instance(obj)) {
3938 st->print(" = ");
3939 java_lang_boxing_object::print(obj, st);
3940 } else if (this == vmClasses::LambdaForm_klass()) {
3941 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3942 if (vmentry != nullptr) {
3943 st->print(" => ");
3944 vmentry->print_value_on(st);
3945 }
3946 } else if (this == vmClasses::MemberName_klass()) {
3947 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3948 if (vmtarget != nullptr) {
3949 st->print(" = ");
3950 vmtarget->print_value_on(st);
3951 } else {
3952 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3953 oop name = java_lang_invoke_MemberName::name(obj);
3954 if (clazz != nullptr) {
3955 clazz->print_value_on(st);
3956 } else {
3957 st->print("null");
3958 }
3959 st->print(".");
3960 if (name != nullptr) {
3961 name->print_value_on(st);
3962 } else {
3963 st->print("null");
3964 }
3965 }
3966 }
3967 }
3968
3969 const char* InstanceKlass::internal_name() const {
3970 return external_name();
3971 }
3972
3973 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3974 const ModuleEntry* module_entry,
3975 const ClassFileStream* cfs) const {
3976
3977 if (ClassListWriter::is_enabled()) {
3978 ClassListWriter::write(this, cfs);
3979 }
3980
3981 print_class_load_helper(loader_data, module_entry, cfs);
3982 print_class_load_cause_logging();
3983 }
3984
3985 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3986 const ModuleEntry* module_entry,
3987 const ClassFileStream* cfs) const {
3988
3989 if (!log_is_enabled(Info, class, load)) {
3990 return;
3991 }
3992
3993 ResourceMark rm;
3994 LogMessage(class, load) msg;
3995 stringStream info_stream;
3996
3997 // Name and class hierarchy info
3998 info_stream.print("%s", external_name());
3999
4000 // Source
4001 if (cfs != nullptr) {
4002 if (cfs->source() != nullptr) {
4003 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4004 if (module_name != nullptr) {
4005 // When the boot loader created the stream, it didn't know the module name
4006 // yet. Let's format it now.
4007 if (cfs->from_boot_loader_modules_image()) {
4008 info_stream.print(" source: jrt:/%s", module_name);
4009 } else {
4010 info_stream.print(" source: %s", cfs->source());
4011 }
4012 } else {
4013 info_stream.print(" source: %s", cfs->source());
4014 }
4015 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4016 Thread* current = Thread::current();
4017 Klass* caller = current->is_Java_thread() ?
4018 JavaThread::cast(current)->security_get_caller_class(1):
4019 nullptr;
4020 // caller can be null, for example, during a JVMTI VM_Init hook
4021 if (caller != nullptr) {
4022 info_stream.print(" source: instance of %s", caller->external_name());
4023 } else {
4024 // source is unknown
4025 }
4026 } else {
4027 oop class_loader = loader_data->class_loader();
4028 info_stream.print(" source: %s", class_loader->klass()->external_name());
4029 }
4030 } else {
4031 assert(this->is_shared(), "must be");
4032 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4033 info_stream.print(" source: shared objects file (top)");
4034 } else {
4035 info_stream.print(" source: shared objects file");
4036 }
4037 }
4038
4039 info_stream.print(" loader:");
4040 if (is_shared()) {
4041 info_stream.print(" %s", SystemDictionaryShared::loader_type_for_shared_class((Klass*)this));
4042 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4043 info_stream.print(" boot_loader");
4044 } else {
4045 oop class_loader = loader_data->class_loader();
4046 if (class_loader != nullptr) {
4047 info_stream.print(" %s", class_loader->klass()->external_name());
4048 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4049 if (cl_name_and_id != nullptr) {
4050 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4051 }
4052 } else {
4053 info_stream.print(" null");
4054 }
4055 }
4056 msg.info("%s", info_stream.as_string());
4057
4058 if (log_is_enabled(Debug, class, load)) {
4059 stringStream debug_stream;
4060
4061 // Class hierarchy info
4062 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4063 p2i(this), p2i(superklass()));
4064
4065 // Interfaces
4066 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4067 debug_stream.print(" interfaces:");
4068 int length = local_interfaces()->length();
4069 for (int i = 0; i < length; i++) {
4070 debug_stream.print(" " PTR_FORMAT,
4071 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4072 }
4073 }
4074
4075 // Class loader
4076 debug_stream.print(" loader: [");
4077 loader_data->print_value_on(&debug_stream);
4078 debug_stream.print("]");
4079
4080 // Classfile checksum
4081 if (cfs) {
4082 debug_stream.print(" bytes: %d checksum: %08x",
4083 cfs->length(),
4084 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4085 cfs->length()));
4086 }
4087
4088 msg.debug("%s", debug_stream.as_string());
4089 }
4090 }
4091
4092 void InstanceKlass::print_class_load_cause_logging() const {
4093 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4094 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4095 JavaThread* current = JavaThread::current();
4096 ResourceMark rm(current);
4097 const char* name = external_name();
4098
4099 if (LogClassLoadingCauseFor == nullptr ||
4100 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4101 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4102 return;
4103 }
4104
4105 // Log Java stack first
4106 {
4107 LogMessage(class, load, cause) msg;
4108 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4109
4110 info_stream.print_cr("Java stack when loading %s:", name);
4111 current->print_stack_on(&info_stream);
4112 }
4113
4114 // Log native stack second
4115 if (log_cause_native) {
4116 // Log to string first so that lines can be indented
4117 stringStream stack_stream;
4118 char buf[O_BUFLEN];
4119 address lastpc = nullptr;
4120 NativeStackPrinter nsp(current);
4121 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4122 true /* print_source_info */, -1 /* max stack */);
4123
4124 LogMessage(class, load, cause, native) msg;
4125 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4126 info_stream.print_cr("Native stack when loading %s:", name);
4127
4128 // Print each native stack line to the log
4129 int size = (int) stack_stream.size();
4130 char* stack = stack_stream.as_string();
4131 char* stack_end = stack + size;
4132 char* line_start = stack;
4133 for (char* p = stack; p < stack_end; p++) {
4134 if (*p == '\n') {
4135 *p = '\0';
4136 info_stream.print_cr("\t%s", line_start);
4137 line_start = p + 1;
4138 }
4139 }
4140 if (line_start < stack_end) {
4141 info_stream.print_cr("\t%s", line_start);
4142 }
4143 }
4144 }
4145 }
4146
4147 // Verification
4148
4149 class VerifyFieldClosure: public BasicOopIterateClosure {
4150 protected:
4151 template <class T> void do_oop_work(T* p) {
4152 oop obj = RawAccess<>::oop_load(p);
4153 if (!oopDesc::is_oop_or_null(obj)) {
4154 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4155 Universe::print_on(tty);
4156 guarantee(false, "boom");
4157 }
4158 }
4159 public:
4160 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4161 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4162 };
4163
4164 void InstanceKlass::verify_on(outputStream* st) {
4165 #ifndef PRODUCT
4166 // Avoid redundant verifies, this really should be in product.
4167 if (_verify_count == Universe::verify_count()) return;
4168 _verify_count = Universe::verify_count();
4169 #endif
4170
4171 // Verify Klass
4172 Klass::verify_on(st);
4173
4174 // Verify that klass is present in ClassLoaderData
4175 guarantee(class_loader_data()->contains_klass(this),
4176 "this class isn't found in class loader data");
4177
4178 // Verify vtables
4179 if (is_linked()) {
4180 // $$$ This used to be done only for m/s collections. Doing it
4181 // always seemed a valid generalization. (DLD -- 6/00)
4182 vtable().verify(st);
4183 }
4184
4185 // Verify first subklass
4186 if (subklass() != nullptr) {
4187 guarantee(subklass()->is_klass(), "should be klass");
4188 }
4189
4190 // Verify siblings
4191 Klass* super = this->super();
4192 Klass* sib = next_sibling();
4193 if (sib != nullptr) {
4194 if (sib == this) {
4195 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4196 }
4197
4198 guarantee(sib->is_klass(), "should be klass");
4199 guarantee(sib->super() == super, "siblings should have same superklass");
4200 }
4201
4202 // Verify local interfaces
4203 if (local_interfaces()) {
4204 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4205 for (int j = 0; j < local_interfaces->length(); j++) {
4206 InstanceKlass* e = local_interfaces->at(j);
4207 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4208 }
4209 }
4210
4211 // Verify transitive interfaces
4212 if (transitive_interfaces() != nullptr) {
4213 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4214 for (int j = 0; j < transitive_interfaces->length(); j++) {
4215 InstanceKlass* e = transitive_interfaces->at(j);
4216 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4217 }
4218 }
4219
4220 // Verify methods
4221 if (methods() != nullptr) {
4222 Array<Method*>* methods = this->methods();
4223 for (int j = 0; j < methods->length(); j++) {
4224 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4225 }
4226 for (int j = 0; j < methods->length() - 1; j++) {
4227 Method* m1 = methods->at(j);
4228 Method* m2 = methods->at(j + 1);
4229 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4230 }
4231 }
4232
4233 // Verify method ordering
4234 if (method_ordering() != nullptr) {
4235 Array<int>* method_ordering = this->method_ordering();
4236 int length = method_ordering->length();
4237 if (JvmtiExport::can_maintain_original_method_order() ||
4238 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4239 guarantee(length == methods()->length(), "invalid method ordering length");
4240 jlong sum = 0;
4241 for (int j = 0; j < length; j++) {
4242 int original_index = method_ordering->at(j);
4243 guarantee(original_index >= 0, "invalid method ordering index");
4244 guarantee(original_index < length, "invalid method ordering index");
4245 sum += original_index;
4246 }
4247 // Verify sum of indices 0,1,...,length-1
4248 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4249 } else {
4250 guarantee(length == 0, "invalid method ordering length");
4251 }
4252 }
4253
4254 // Verify default methods
4255 if (default_methods() != nullptr) {
4256 Array<Method*>* methods = this->default_methods();
4257 for (int j = 0; j < methods->length(); j++) {
4258 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4259 }
4260 for (int j = 0; j < methods->length() - 1; j++) {
4261 Method* m1 = methods->at(j);
4262 Method* m2 = methods->at(j + 1);
4263 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4264 }
4265 }
4266
4267 // Verify JNI static field identifiers
4268 if (jni_ids() != nullptr) {
4269 jni_ids()->verify(this);
4270 }
4271
4272 // Verify other fields
4273 if (constants() != nullptr) {
4274 guarantee(constants()->is_constantPool(), "should be constant pool");
4275 }
4276 }
4277
4278 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4279 Klass::oop_verify_on(obj, st);
4280 VerifyFieldClosure blk;
4281 obj->oop_iterate(&blk);
4282 }
4283
4284
4285 // JNIid class for jfieldIDs only
4286 // Note to reviewers:
4287 // These JNI functions are just moved over to column 1 and not changed
4288 // in the compressed oops workspace.
4289 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4290 _holder = holder;
4291 _offset = offset;
4292 _next = next;
4293 DEBUG_ONLY(_is_static_field_id = false;)
4294 }
4295
4296
4297 JNIid* JNIid::find(int offset) {
4298 JNIid* current = this;
4299 while (current != nullptr) {
4300 if (current->offset() == offset) return current;
4301 current = current->next();
4302 }
4303 return nullptr;
4304 }
4305
4306 void JNIid::deallocate(JNIid* current) {
4307 while (current != nullptr) {
4308 JNIid* next = current->next();
4309 delete current;
4310 current = next;
4311 }
4312 }
4313
4314
4315 void JNIid::verify(Klass* holder) {
4316 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4317 int end_field_offset;
4318 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4319
4320 JNIid* current = this;
4321 while (current != nullptr) {
4322 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4323 #ifdef ASSERT
4324 int o = current->offset();
4325 if (current->is_static_field_id()) {
4326 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4327 }
4328 #endif
4329 current = current->next();
4330 }
4331 }
4332
4333 void InstanceKlass::set_init_state(ClassState state) {
4334 #ifdef ASSERT
4335 bool good_state = is_shared() ? (_init_state <= state)
4336 : (_init_state < state);
4337 assert(good_state || state == allocated, "illegal state transition");
4338 #endif
4339 assert(_init_thread == nullptr, "should be cleared before state change");
4340 Atomic::release_store(&_init_state, state);
4341 }
4342
4343 #if INCLUDE_JVMTI
4344
4345 // RedefineClasses() support for previous versions
4346
4347 // Globally, there is at least one previous version of a class to walk
4348 // during class unloading, which is saved because old methods in the class
4349 // are still running. Otherwise the previous version list is cleaned up.
4350 bool InstanceKlass::_should_clean_previous_versions = false;
4351
4352 // Returns true if there are previous versions of a class for class
4353 // unloading only. Also resets the flag to false. purge_previous_version
4354 // will set the flag to true if there are any left, i.e., if there's any
4355 // work to do for next time. This is to avoid the expensive code cache
4356 // walk in CLDG::clean_deallocate_lists().
4357 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4358 bool ret = _should_clean_previous_versions;
4359 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4360 ret ? "true" : "false");
4361 _should_clean_previous_versions = false;
4362 return ret;
4363 }
4364
4365 // This nulls out jmethodIDs for all methods in 'klass'
4366 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4367 // during class unloading.
4368 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4369 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4370 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4371 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4372 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4373 Array<Method*>* method_refs = klass->methods();
4374 for (int k = 0; k < method_refs->length(); k++) {
4375 Method* method = method_refs->at(k);
4376 if (method != nullptr && method->is_obsolete()) {
4377 method->clear_jmethod_id();
4378 }
4379 }
4380 }
4381
4382 // Purge previous versions before adding new previous versions of the class and
4383 // during class unloading.
4384 void InstanceKlass::purge_previous_version_list() {
4385 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4386 assert(has_been_redefined(), "Should only be called for main class");
4387
4388 // Quick exit.
4389 if (previous_versions() == nullptr) {
4390 return;
4391 }
4392
4393 // This klass has previous versions so see what we can cleanup
4394 // while it is safe to do so.
4395
4396 int deleted_count = 0; // leave debugging breadcrumbs
4397 int live_count = 0;
4398 ClassLoaderData* loader_data = class_loader_data();
4399 assert(loader_data != nullptr, "should never be null");
4400
4401 ResourceMark rm;
4402 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4403
4404 // previous versions are linked together through the InstanceKlass
4405 InstanceKlass* pv_node = previous_versions();
4406 InstanceKlass* last = this;
4407 int version = 0;
4408
4409 // check the previous versions list
4410 for (; pv_node != nullptr; ) {
4411
4412 ConstantPool* pvcp = pv_node->constants();
4413 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4414
4415 if (!pvcp->on_stack()) {
4416 // If the constant pool isn't on stack, none of the methods
4417 // are executing. Unlink this previous_version.
4418 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4419 // so will be deallocated during the next phase of class unloading.
4420 log_trace(redefine, class, iklass, purge)
4421 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4422 // Unlink from previous version list.
4423 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4424 InstanceKlass* next = pv_node->previous_versions();
4425 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4426 pv_node->link_previous_versions(nullptr); // point next to null
4427 last->link_previous_versions(next);
4428 // Delete this node directly. Nothing is referring to it and we don't
4429 // want it to increase the counter for metadata to delete in CLDG.
4430 MetadataFactory::free_metadata(loader_data, pv_node);
4431 pv_node = next;
4432 deleted_count++;
4433 version++;
4434 continue;
4435 } else {
4436 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4437 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4438 live_count++;
4439 if (pvcp->is_shared()) {
4440 // Shared previous versions can never be removed so no cleaning is needed.
4441 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4442 } else {
4443 // Previous version alive, set that clean is needed for next time.
4444 _should_clean_previous_versions = true;
4445 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4446 }
4447 }
4448
4449 // next previous version
4450 last = pv_node;
4451 pv_node = pv_node->previous_versions();
4452 version++;
4453 }
4454 log_trace(redefine, class, iklass, purge)
4455 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4456 }
4457
4458 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4459 int emcp_method_count) {
4460 int obsolete_method_count = old_methods->length() - emcp_method_count;
4461
4462 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4463 _previous_versions != nullptr) {
4464 // We have a mix of obsolete and EMCP methods so we have to
4465 // clear out any matching EMCP method entries the hard way.
4466 int local_count = 0;
4467 for (int i = 0; i < old_methods->length(); i++) {
4468 Method* old_method = old_methods->at(i);
4469 if (old_method->is_obsolete()) {
4470 // only obsolete methods are interesting
4471 Symbol* m_name = old_method->name();
4472 Symbol* m_signature = old_method->signature();
4473
4474 // previous versions are linked together through the InstanceKlass
4475 int j = 0;
4476 for (InstanceKlass* prev_version = _previous_versions;
4477 prev_version != nullptr;
4478 prev_version = prev_version->previous_versions(), j++) {
4479
4480 Array<Method*>* method_refs = prev_version->methods();
4481 for (int k = 0; k < method_refs->length(); k++) {
4482 Method* method = method_refs->at(k);
4483
4484 if (!method->is_obsolete() &&
4485 method->name() == m_name &&
4486 method->signature() == m_signature) {
4487 // The current RedefineClasses() call has made all EMCP
4488 // versions of this method obsolete so mark it as obsolete
4489 log_trace(redefine, class, iklass, add)
4490 ("%s(%s): flush obsolete method @%d in version @%d",
4491 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4492
4493 method->set_is_obsolete();
4494 break;
4495 }
4496 }
4497
4498 // The previous loop may not find a matching EMCP method, but
4499 // that doesn't mean that we can optimize and not go any
4500 // further back in the PreviousVersion generations. The EMCP
4501 // method for this generation could have already been made obsolete,
4502 // but there still may be an older EMCP method that has not
4503 // been made obsolete.
4504 }
4505
4506 if (++local_count >= obsolete_method_count) {
4507 // no more obsolete methods so bail out now
4508 break;
4509 }
4510 }
4511 }
4512 }
4513 }
4514
4515 // Save the scratch_class as the previous version if any of the methods are running.
4516 // The previous_versions are used to set breakpoints in EMCP methods and they are
4517 // also used to clean MethodData links to redefined methods that are no longer running.
4518 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4519 int emcp_method_count) {
4520 assert(Thread::current()->is_VM_thread(),
4521 "only VMThread can add previous versions");
4522
4523 ResourceMark rm;
4524 log_trace(redefine, class, iklass, add)
4525 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4526
4527 // Clean out old previous versions for this class
4528 purge_previous_version_list();
4529
4530 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4531 // a previous redefinition may be made obsolete by this redefinition.
4532 Array<Method*>* old_methods = scratch_class->methods();
4533 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4534
4535 // If the constant pool for this previous version of the class
4536 // is not marked as being on the stack, then none of the methods
4537 // in this previous version of the class are on the stack so
4538 // we don't need to add this as a previous version.
4539 ConstantPool* cp_ref = scratch_class->constants();
4540 if (!cp_ref->on_stack()) {
4541 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4542 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4543 return;
4544 }
4545
4546 // Add previous version if any methods are still running or if this is
4547 // a shared class which should never be removed.
4548 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4549 scratch_class->link_previous_versions(previous_versions());
4550 link_previous_versions(scratch_class);
4551 if (cp_ref->is_shared()) {
4552 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4553 } else {
4554 // We only set clean_previous_versions flag for processing during class
4555 // unloading for non-shared classes.
4556 _should_clean_previous_versions = true;
4557 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4558 }
4559 } // end add_previous_version()
4560
4561 #endif // INCLUDE_JVMTI
4562
4563 Method* InstanceKlass::method_with_idnum(int idnum) const {
4564 Method* m = nullptr;
4565 if (idnum < methods()->length()) {
4566 m = methods()->at(idnum);
4567 }
4568 if (m == nullptr || m->method_idnum() != idnum) {
4569 for (int index = 0; index < methods()->length(); ++index) {
4570 m = methods()->at(index);
4571 if (m->method_idnum() == idnum) {
4572 return m;
4573 }
4574 }
4575 // None found, return null for the caller to handle.
4576 return nullptr;
4577 }
4578 return m;
4579 }
4580
4581
4582 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4583 if (idnum >= methods()->length()) {
4584 return nullptr;
4585 }
4586 Method* m = methods()->at(idnum);
4587 if (m != nullptr && m->orig_method_idnum() == idnum) {
4588 return m;
4589 }
4590 // Obsolete method idnum does not match the original idnum
4591 for (int index = 0; index < methods()->length(); ++index) {
4592 m = methods()->at(index);
4593 if (m->orig_method_idnum() == idnum) {
4594 return m;
4595 }
4596 }
4597 // None found, return null for the caller to handle.
4598 return nullptr;
4599 }
4600
4601
4602 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4603 const InstanceKlass* holder = get_klass_version(version);
4604 if (holder == nullptr) {
4605 return nullptr; // The version of klass is gone, no method is found
4606 }
4607 return holder->method_with_orig_idnum(idnum);
4608 }
4609
4610 #if INCLUDE_JVMTI
4611 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4612 return _cached_class_file;
4613 }
4614
4615 jint InstanceKlass::get_cached_class_file_len() {
4616 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4617 }
4618
4619 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4620 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4621 }
4622 #endif
4623
4624 // Make a step iterating over the class hierarchy under the root class.
4625 // Skips subclasses if requested.
4626 void ClassHierarchyIterator::next() {
4627 assert(_current != nullptr, "required");
4628 if (_visit_subclasses && _current->subklass() != nullptr) {
4629 _current = _current->subklass();
4630 return; // visit next subclass
4631 }
4632 _visit_subclasses = true; // reset
4633 while (_current->next_sibling() == nullptr && _current != _root) {
4634 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4635 }
4636 if (_current == _root) {
4637 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4638 _current = nullptr;
4639 return;
4640 }
4641 _current = _current->next_sibling();
4642 return; // visit next sibling subclass
4643 }