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 "oops/trainingData.hpp"
78 #include "prims/jvmtiExport.hpp"
79 #include "prims/jvmtiRedefineClasses.hpp"
80 #include "prims/jvmtiThreadState.hpp"
81 #include "prims/methodComparator.hpp"
82 #include "runtime/arguments.hpp"
83 #include "runtime/deoptimization.hpp"
84 #include "runtime/atomic.hpp"
85 #include "runtime/fieldDescriptor.inline.hpp"
86 #include "runtime/handles.inline.hpp"
87 #include "runtime/javaCalls.hpp"
88 #include "runtime/javaThread.inline.hpp"
89 #include "runtime/mutexLocker.hpp"
90 #include "runtime/orderAccess.hpp"
91 #include "runtime/os.inline.hpp"
92 #include "runtime/reflection.hpp"
93 #include "runtime/runtimeUpcalls.hpp"
94 #include "runtime/synchronizer.hpp"
95 #include "runtime/threads.hpp"
96 #include "services/classLoadingService.hpp"
97 #include "services/finalizerService.hpp"
98 #include "services/threadService.hpp"
99 #include "utilities/dtrace.hpp"
100 #include "utilities/events.hpp"
101 #include "utilities/macros.hpp"
102 #include "utilities/nativeStackPrinter.hpp"
103 #include "utilities/pair.hpp"
104 #include "utilities/stringUtils.hpp"
105 #ifdef COMPILER1
106 #include "c1/c1_Compiler.hpp"
107 #endif
108 #if INCLUDE_JFR
109 #include "jfr/jfrEvents.hpp"
110 #endif
111
112 #ifdef DTRACE_ENABLED
113
114
115 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
116 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
117 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
118 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
119 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
120 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
121 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
122 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
124 { \
125 char* data = nullptr; \
126 int len = 0; \
127 Symbol* clss_name = name(); \
128 if (clss_name != nullptr) { \
129 data = (char*)clss_name->bytes(); \
130 len = clss_name->utf8_length(); \
131 } \
132 HOTSPOT_CLASS_INITIALIZATION_##type( \
133 data, len, (void*)class_loader(), thread_type); \
134 }
135
136 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
137 { \
138 char* data = nullptr; \
139 int len = 0; \
140 Symbol* clss_name = name(); \
141 if (clss_name != nullptr) { \
142 data = (char*)clss_name->bytes(); \
143 len = clss_name->utf8_length(); \
144 } \
145 HOTSPOT_CLASS_INITIALIZATION_##type( \
146 data, len, (void*)class_loader(), thread_type, wait); \
147 }
148
149 #else // ndef DTRACE_ENABLED
150
151 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
152 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
153
154 #endif // ndef DTRACE_ENABLED
155
156 bool InstanceKlass::_finalization_enabled = true;
157
158 static inline bool is_class_loader(const Symbol* class_name,
159 const ClassFileParser& parser) {
160 assert(class_name != nullptr, "invariant");
161
162 if (class_name == vmSymbols::java_lang_ClassLoader()) {
163 return true;
164 }
165
166 if (vmClasses::ClassLoader_klass_loaded()) {
167 const Klass* const super_klass = parser.super_klass();
168 if (super_klass != nullptr) {
169 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
170 return true;
171 }
172 }
173 }
174 return false;
175 }
176
177 static inline bool is_stack_chunk_class(const Symbol* class_name,
178 const ClassLoaderData* loader_data) {
179 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
180 loader_data->is_the_null_class_loader_data());
181 }
182
183 // private: called to verify that k is a static member of this nest.
184 // We know that k is an instance class in the same package and hence the
185 // same classloader.
186 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
187 assert(!is_hidden(), "unexpected hidden class");
188 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
189 if (log_is_enabled(Trace, class, nestmates)) {
190 ResourceMark rm(current);
191 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
192 k->external_name(), this->external_name());
193 }
194 return false;
195 }
196
197 if (log_is_enabled(Trace, class, nestmates)) {
198 ResourceMark rm(current);
199 log_trace(class, nestmates)("Checking nest membership of %s in %s",
200 k->external_name(), this->external_name());
201 }
202
203 // Check for the named class in _nest_members.
204 // We don't resolve, or load, any classes.
205 for (int i = 0; i < _nest_members->length(); i++) {
206 int cp_index = _nest_members->at(i);
207 Symbol* name = _constants->klass_name_at(cp_index);
208 if (name == k->name()) {
209 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
210 return true;
211 }
212 }
213 log_trace(class, nestmates)("- class is NOT a nest member!");
214 return false;
215 }
216
217 // Called to verify that k is a permitted subclass of this class.
218 // The incoming stringStream is used to format the messages for error logging and for the caller
219 // to use for exception throwing.
220 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
221 Thread* current = Thread::current();
222 assert(k != nullptr, "sanity check");
223 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
224 "unexpected empty _permitted_subclasses array");
225
226 if (log_is_enabled(Trace, class, sealed)) {
227 ResourceMark rm(current);
228 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
229 k->external_name(), this->external_name());
230 }
231
232 // Check that the class and its super are in the same module.
233 if (k->module() != this->module()) {
234 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
235 "and sealed class %s is in module '%s' with loader %s",
236 k->external_name(),
237 k->module()->name_as_C_string(),
238 k->module()->loader_data()->loader_name_and_id(),
239 this->external_name(),
240 this->module()->name_as_C_string(),
241 this->module()->loader_data()->loader_name_and_id());
242 log_trace(class, sealed)(" - %s", ss.as_string());
243 return false;
244 }
245
246 if (!k->is_public() && !is_same_class_package(k)) {
247 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
248 "and sealed class %s is in package '%s' with classloader %s",
249 k->external_name(),
250 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
251 k->module()->loader_data()->loader_name_and_id(),
252 this->external_name(),
253 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
254 this->module()->loader_data()->loader_name_and_id());
255 log_trace(class, sealed)(" - %s", ss.as_string());
256 return false;
257 }
258
259 for (int i = 0; i < _permitted_subclasses->length(); i++) {
260 int cp_index = _permitted_subclasses->at(i);
261 Symbol* name = _constants->klass_name_at(cp_index);
262 if (name == k->name()) {
263 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
264 return true;
265 }
266 }
267
268 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
269 k->external_name(), this->external_name());
270 log_trace(class, sealed)(" - %s", ss.as_string());
271 return false;
272 }
273
274 // Return nest-host class, resolving, validating and saving it if needed.
275 // In cases where this is called from a thread that cannot do classloading
276 // (such as a native JIT thread) then we simply return null, which in turn
277 // causes the access check to return false. Such code will retry the access
278 // from a more suitable environment later. Otherwise the _nest_host is always
279 // set once this method returns.
280 // Any errors from nest-host resolution must be preserved so they can be queried
281 // from higher-level access checking code, and reported as part of access checking
282 // exceptions.
283 // VirtualMachineErrors are propagated with a null return.
284 // Under any conditions where the _nest_host can be set to non-null the resulting
285 // value of it and, if applicable, the nest host resolution/validation error,
286 // are idempotent.
287 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
288 InstanceKlass* nest_host_k = _nest_host;
289 if (nest_host_k != nullptr) {
290 return nest_host_k;
291 }
292
293 ResourceMark rm(THREAD);
294
295 // need to resolve and save our nest-host class.
296 if (_nest_host_index != 0) { // we have a real nest_host
297 // Before trying to resolve check if we're in a suitable context
298 bool can_resolve = THREAD->can_call_java();
299 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
300 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
301 this->external_name());
302 return nullptr; // sentinel to say "try again from a different context"
303 }
304
305 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
306 this->external_name(),
307 _constants->klass_name_at(_nest_host_index)->as_C_string());
308
309 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
310 if (HAS_PENDING_EXCEPTION) {
311 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
312 return nullptr; // propagate VMEs
313 }
314 stringStream ss;
315 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
316 ss.print("Nest host resolution of %s with host %s failed: ",
317 this->external_name(), target_host_class);
318 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
319 const char* msg = ss.as_string(true /* on C-heap */);
320 constantPoolHandle cph(THREAD, constants());
321 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
322 CLEAR_PENDING_EXCEPTION;
323
324 log_trace(class, nestmates)("%s", msg);
325 } else {
326 // A valid nest-host is an instance class in the current package that lists this
327 // class as a nest member. If any of these conditions are not met the class is
328 // its own nest-host.
329 const char* error = nullptr;
330
331 // JVMS 5.4.4 indicates package check comes first
332 if (is_same_class_package(k)) {
333 // Now check actual membership. We can't be a member if our "host" is
334 // not an instance class.
335 if (k->is_instance_klass()) {
336 nest_host_k = InstanceKlass::cast(k);
337 bool is_member = nest_host_k->has_nest_member(THREAD, this);
338 if (is_member) {
339 _nest_host = nest_host_k; // save resolved nest-host value
340
341 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
342 this->external_name(), k->external_name());
343 return nest_host_k;
344 } else {
345 error = "current type is not listed as a nest member";
346 }
347 } else {
348 error = "host is not an instance class";
349 }
350 } else {
351 error = "types are in different packages";
352 }
353
354 // something went wrong, so record what and log it
355 {
356 stringStream ss;
357 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
358 this->external_name(),
359 this->class_loader_data()->loader_name_and_id(),
360 k->external_name(),
361 k->class_loader_data()->loader_name_and_id(),
362 error);
363 const char* msg = ss.as_string(true /* on C-heap */);
364 constantPoolHandle cph(THREAD, constants());
365 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
366 log_trace(class, nestmates)("%s", msg);
367 }
368 }
369 } else {
370 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
371 this->external_name());
372 }
373
374 // Either not in an explicit nest, or else an error occurred, so
375 // the nest-host is set to `this`. Any thread that sees this assignment
376 // will also see any setting of nest_host_error(), if applicable.
377 return (_nest_host = this);
378 }
379
380 // Dynamic nest member support: set this class's nest host to the given class.
381 // This occurs as part of the class definition, as soon as the instanceKlass
382 // has been created and doesn't require further resolution. The code:
383 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
384 // results in:
385 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
386 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
387 // We also know the "host" is a valid nest-host in the same package so we can
388 // assert some of those facts.
389 void InstanceKlass::set_nest_host(InstanceKlass* host) {
390 assert(is_hidden(), "must be a hidden class");
391 assert(host != nullptr, "null nest host specified");
392 assert(_nest_host == nullptr, "current class has resolved nest-host");
393 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
394 nest_host_error());
395 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
396 (host->_nest_host == host), "proposed host is not a valid nest-host");
397 // Can't assert this as package is not set yet:
398 // assert(is_same_class_package(host), "proposed host is in wrong package");
399
400 if (log_is_enabled(Trace, class, nestmates)) {
401 ResourceMark rm;
402 const char* msg = "";
403 // a hidden class does not expect a statically defined nest-host
404 if (_nest_host_index > 0) {
405 msg = "(the NestHost attribute in the current class is ignored)";
406 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
407 msg = "(the NestMembers attribute in the current class is ignored)";
408 }
409 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
410 this->external_name(),
411 host->external_name(),
412 msg);
413 }
414 // set dynamic nest host
415 _nest_host = host;
416 // Record dependency to keep nest host from being unloaded before this class.
417 ClassLoaderData* this_key = class_loader_data();
418 assert(this_key != nullptr, "sanity");
419 this_key->record_dependency(host);
420 }
421
422 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
423 // or we are k's nest_host - all of which is covered by comparing the two
424 // resolved_nest_hosts.
425 // Any exceptions (i.e. VMEs) are propagated.
426 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
427
428 assert(this != k, "this should be handled by higher-level code");
429
430 // Per JVMS 5.4.4 we first resolve and validate the current class, then
431 // the target class k.
432
433 InstanceKlass* cur_host = nest_host(CHECK_false);
434 if (cur_host == nullptr) {
435 return false;
436 }
437
438 Klass* k_nest_host = k->nest_host(CHECK_false);
439 if (k_nest_host == nullptr) {
440 return false;
441 }
442
443 bool access = (cur_host == k_nest_host);
444
445 ResourceMark rm(THREAD);
446 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
447 this->external_name(),
448 access ? "" : "NOT ",
449 k->external_name());
450 return access;
451 }
452
453 const char* InstanceKlass::nest_host_error() {
454 if (_nest_host_index == 0) {
455 return nullptr;
456 } else {
457 constantPoolHandle cph(Thread::current(), constants());
458 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
459 }
460 }
461
462 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
463 bool use_class_space, TRAPS) throw() {
464 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
465 }
466
467 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
468 const int size = InstanceKlass::size(parser.vtable_size(),
469 parser.itable_size(),
470 nonstatic_oop_map_size(parser.total_oop_map_count()),
471 parser.is_interface());
472
473 const Symbol* const class_name = parser.class_name();
474 assert(class_name != nullptr, "invariant");
475 ClassLoaderData* loader_data = parser.loader_data();
476 assert(loader_data != nullptr, "invariant");
477
478 InstanceKlass* ik;
479 const bool use_class_space = parser.klass_needs_narrow_id();
480
481 // Allocation
482 if (parser.is_instance_ref_klass()) {
483 // java.lang.ref.Reference
484 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
485 } else if (class_name == vmSymbols::java_lang_Class()) {
486 // mirror - java.lang.Class
487 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
488 } else if (is_stack_chunk_class(class_name, loader_data)) {
489 // stack chunk
490 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
491 } else if (is_class_loader(class_name, parser)) {
492 // class loader - java.lang.ClassLoader
493 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
494 } else {
495 // normal
496 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
497 }
498
499 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
500 assert(CompressedKlassPointers::is_encodable(ik),
501 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
502 }
503
504 // Check for pending exception before adding to the loader data and incrementing
505 // class count. Can get OOM here.
506 if (HAS_PENDING_EXCEPTION) {
507 return nullptr;
508 }
509
510 return ik;
511 }
512
513
514 // copy method ordering from resource area to Metaspace
515 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
516 if (m != nullptr) {
517 // allocate a new array and copy contents (memcpy?)
518 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
519 for (int i = 0; i < m->length(); i++) {
520 _method_ordering->at_put(i, m->at(i));
521 }
522 } else {
523 _method_ordering = Universe::the_empty_int_array();
524 }
525 }
526
527 // create a new array of vtable_indices for default methods
528 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
529 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
530 assert(default_vtable_indices() == nullptr, "only create once");
531 set_default_vtable_indices(vtable_indices);
532 return vtable_indices;
533 }
534
535
536 InstanceKlass::InstanceKlass() {
537 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
538 }
539
540 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
541 Klass(kind),
542 _nest_members(nullptr),
543 _nest_host(nullptr),
544 _permitted_subclasses(nullptr),
545 _record_components(nullptr),
546 _static_field_size(parser.static_field_size()),
547 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
548 _itable_len(parser.itable_size()),
549 _nest_host_index(0),
550 _init_state(allocated),
551 _reference_type(reference_type),
552 _init_thread(nullptr)
553 {
554 set_vtable_length(parser.vtable_size());
555 set_access_flags(parser.access_flags());
556 if (parser.is_hidden()) set_is_hidden();
557 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
558 false));
559
560 assert(nullptr == _methods, "underlying memory not zeroed?");
561 assert(is_instance_klass(), "is layout incorrect?");
562 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
563 }
564
565 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
566 Array<Method*>* methods) {
567 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
568 !methods->is_shared()) {
569 for (int i = 0; i < methods->length(); i++) {
570 Method* method = methods->at(i);
571 if (method == nullptr) continue; // maybe null if error processing
572 // Only want to delete methods that are not executing for RedefineClasses.
573 // The previous version will point to them so they're not totally dangling
574 assert (!method->on_stack(), "shouldn't be called with methods on stack");
575 MetadataFactory::free_metadata(loader_data, method);
576 }
577 MetadataFactory::free_array<Method*>(loader_data, methods);
578 }
579 }
580
581 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
582 const Klass* super_klass,
583 Array<InstanceKlass*>* local_interfaces,
584 Array<InstanceKlass*>* transitive_interfaces) {
585 // Only deallocate transitive interfaces if not empty, same as super class
586 // or same as local interfaces. See code in parseClassFile.
587 Array<InstanceKlass*>* ti = transitive_interfaces;
588 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
589 // check that the interfaces don't come from super class
590 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
591 InstanceKlass::cast(super_klass)->transitive_interfaces();
592 if (ti != sti && ti != nullptr && !ti->is_shared()) {
593 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
594 }
595 }
596
597 // local interfaces can be empty
598 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
599 local_interfaces != nullptr && !local_interfaces->is_shared()) {
600 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
601 }
602 }
603
604 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
605 Array<RecordComponent*>* record_components) {
606 if (record_components != nullptr && !record_components->is_shared()) {
607 for (int i = 0; i < record_components->length(); i++) {
608 RecordComponent* record_component = record_components->at(i);
609 MetadataFactory::free_metadata(loader_data, record_component);
610 }
611 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
612 }
613 }
614
615 // This function deallocates the metadata and C heap pointers that the
616 // InstanceKlass points to.
617 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
618 // Orphan the mirror first, CMS thinks it's still live.
619 if (java_mirror() != nullptr) {
620 java_lang_Class::set_klass(java_mirror(), nullptr);
621 }
622
623 // Also remove mirror from handles
624 loader_data->remove_handle(_java_mirror);
625
626 // Need to take this class off the class loader data list.
627 loader_data->remove_class(this);
628
629 // The array_klass for this class is created later, after error handling.
630 // For class redefinition, we keep the original class so this scratch class
631 // doesn't have an array class. Either way, assert that there is nothing
632 // to deallocate.
633 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
634
635 // Release C heap allocated data that this points to, which includes
636 // reference counting symbol names.
637 // Can't release the constant pool or MethodData C heap data here because the constant
638 // pool can be deallocated separately from the InstanceKlass for default methods and
639 // redefine classes. MethodData can also be released separately.
640 release_C_heap_structures(/* release_sub_metadata */ false);
641
642 deallocate_methods(loader_data, methods());
643 set_methods(nullptr);
644
645 deallocate_record_components(loader_data, record_components());
646 set_record_components(nullptr);
647
648 if (method_ordering() != nullptr &&
649 method_ordering() != Universe::the_empty_int_array() &&
650 !method_ordering()->is_shared()) {
651 MetadataFactory::free_array<int>(loader_data, method_ordering());
652 }
653 set_method_ordering(nullptr);
654
655 // default methods can be empty
656 if (default_methods() != nullptr &&
657 default_methods() != Universe::the_empty_method_array() &&
658 !default_methods()->is_shared()) {
659 MetadataFactory::free_array<Method*>(loader_data, default_methods());
660 }
661 // Do NOT deallocate the default methods, they are owned by superinterfaces.
662 set_default_methods(nullptr);
663
664 // default methods vtable indices can be empty
665 if (default_vtable_indices() != nullptr &&
666 !default_vtable_indices()->is_shared()) {
667 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
668 }
669 set_default_vtable_indices(nullptr);
670
671
672 // This array is in Klass, but remove it with the InstanceKlass since
673 // this place would be the only caller and it can share memory with transitive
674 // interfaces.
675 if (secondary_supers() != nullptr &&
676 secondary_supers() != Universe::the_empty_klass_array() &&
677 // see comments in compute_secondary_supers about the following cast
678 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
679 !secondary_supers()->is_shared()) {
680 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
681 }
682 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
683
684 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
685 set_transitive_interfaces(nullptr);
686 set_local_interfaces(nullptr);
687
688 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
689 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
690 }
691 set_fieldinfo_stream(nullptr);
692
693 if (fields_status() != nullptr && !fields_status()->is_shared()) {
694 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
695 }
696 set_fields_status(nullptr);
697
698 // If a method from a redefined class is using this constant pool, don't
699 // delete it, yet. The new class's previous version will point to this.
700 if (constants() != nullptr) {
701 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
702 if (!constants()->is_shared()) {
703 MetadataFactory::free_metadata(loader_data, constants());
704 }
705 // Delete any cached resolution errors for the constant pool
706 SystemDictionary::delete_resolution_error(constants());
707
708 set_constants(nullptr);
709 }
710
711 if (inner_classes() != nullptr &&
712 inner_classes() != Universe::the_empty_short_array() &&
713 !inner_classes()->is_shared()) {
714 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
715 }
716 set_inner_classes(nullptr);
717
718 if (nest_members() != nullptr &&
719 nest_members() != Universe::the_empty_short_array() &&
720 !nest_members()->is_shared()) {
721 MetadataFactory::free_array<jushort>(loader_data, nest_members());
722 }
723 set_nest_members(nullptr);
724
725 if (permitted_subclasses() != nullptr &&
726 permitted_subclasses() != Universe::the_empty_short_array() &&
727 !permitted_subclasses()->is_shared()) {
728 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
729 }
730 set_permitted_subclasses(nullptr);
731
732 // We should deallocate the Annotations instance if it's not in shared spaces.
733 if (annotations() != nullptr && !annotations()->is_shared()) {
734 MetadataFactory::free_metadata(loader_data, annotations());
735 }
736 set_annotations(nullptr);
737
738 SystemDictionaryShared::handle_class_unloading(this);
739
740 #if INCLUDE_CDS_JAVA_HEAP
741 if (CDSConfig::is_dumping_heap()) {
742 HeapShared::remove_scratch_objects(this);
743 }
744 #endif
745 }
746
747 bool InstanceKlass::is_record() const {
748 return _record_components != nullptr &&
749 is_final() &&
750 java_super() == vmClasses::Record_klass();
751 }
752
753 bool InstanceKlass::is_sealed() const {
754 return _permitted_subclasses != nullptr &&
755 _permitted_subclasses != Universe::the_empty_short_array();
756 }
757
758 // JLS 8.9: An enum class is either implicitly final and derives
759 // from java.lang.Enum, or else is implicitly sealed to its
760 // anonymous subclasses. This query detects both kinds.
761 // It does not validate the finality or
762 // sealing conditions: it merely checks for a super of Enum.
763 // This is sufficient for recognizing well-formed enums.
764 bool InstanceKlass::is_enum_subclass() const {
765 InstanceKlass* s = java_super();
766 return (s == vmClasses::Enum_klass() ||
767 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
768 }
769
770 bool InstanceKlass::should_be_initialized() const {
771 return !is_initialized();
772 }
773
774 klassItable InstanceKlass::itable() const {
775 return klassItable(const_cast<InstanceKlass*>(this));
776 }
777
778 // JVMTI spec thinks there are signers and protection domain in the
779 // instanceKlass. These accessors pretend these fields are there.
780 // The hprof specification also thinks these fields are in InstanceKlass.
781 oop InstanceKlass::protection_domain() const {
782 // return the protection_domain from the mirror
783 return java_lang_Class::protection_domain(java_mirror());
784 }
785
786 objArrayOop InstanceKlass::signers() const {
787 // return the signers from the mirror
788 return java_lang_Class::signers(java_mirror());
789 }
790
791 oop InstanceKlass::init_lock() const {
792 // return the init lock from the mirror
793 oop lock = java_lang_Class::init_lock(java_mirror());
794 // Prevent reordering with any access of initialization state
795 OrderAccess::loadload();
796 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
797 "only fully initialized state can have a null lock");
798 return lock;
799 }
800
801 // Set the initialization lock to null so the object can be GC'ed. Any racing
802 // threads to get this lock will see a null lock and will not lock.
803 // That's okay because they all check for initialized state after getting
804 // the lock and return.
805 void InstanceKlass::fence_and_clear_init_lock() {
806 // make sure previous stores are all done, notably the init_state.
807 OrderAccess::storestore();
808 java_lang_Class::clear_init_lock(java_mirror());
809 assert(!is_not_initialized(), "class must be initialized now");
810 }
811
812
813 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
814 // process. The step comments refers to the procedure described in that section.
815 // Note: implementation moved to static method to expose the this pointer.
816 void InstanceKlass::initialize(TRAPS) {
817 if (this->should_be_initialized()) {
818 initialize_impl(CHECK);
819 // Note: at this point the class may be initialized
820 // OR it may be in the state of being initialized
821 // in case of recursive initialization!
822 } else {
823 assert(is_initialized(), "sanity check");
824 }
825 }
826
827 #ifdef ASSERT
828 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
829 assert(has_aot_initialized_mirror(), "must be");
830
831 InstanceKlass* s = java_super();
832 if (s != nullptr) {
833 DEBUG_ONLY(ResourceMark rm);
834 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
835 s->external_name(), external_name());
836 s->assert_no_clinit_will_run_for_aot_initialized_class();
837 }
838
839 Array<InstanceKlass*>* interfaces = local_interfaces();
840 int len = interfaces->length();
841 for (int i = 0; i < len; i++) {
842 InstanceKlass* intf = interfaces->at(i);
843 if (!intf->is_initialized()) {
844 ResourceMark rm;
845 // Note: an interface needs to be marked as is_initialized() only if
846 // - it has a <clinit>
847 // - it has declared a default method.
848 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
849 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
850 intf->external_name(), external_name());
851 }
852 }
853 }
854 #endif
855
856 #if INCLUDE_CDS
857 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
858 assert(has_aot_initialized_mirror(), "must be");
859 assert(CDSConfig::is_loading_heap(), "must be");
860 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
861 assert_no_clinit_will_run_for_aot_initialized_class();
862
863 if (is_initialized()) {
864 return;
865 }
866
867 if (log_is_enabled(Info, cds, init)) {
868 ResourceMark rm;
869 log_info(cds, init)("%s (aot-inited)", external_name());
870 }
871
872 link_class(CHECK);
873
874 #ifdef ASSERT
875 {
876 Handle h_init_lock(THREAD, init_lock());
877 ObjectLocker ol(h_init_lock, THREAD);
878 assert(!is_initialized(), "sanity");
879 assert(!is_being_initialized(), "sanity");
880 assert(!is_in_error_state(), "sanity");
881 }
882 #endif
883
884 set_init_thread(THREAD);
885 set_initialization_state_and_notify(fully_initialized, CHECK);
886 AOTClassInitializer::call_runtime_setup(THREAD, this);
887 }
888 #endif
889
890 bool InstanceKlass::verify_code(TRAPS) {
891 // 1) Verify the bytecodes
892 return Verifier::verify(this, should_verify_class(), THREAD);
893 }
894
895 void InstanceKlass::link_class(TRAPS) {
896 assert(is_loaded(), "must be loaded");
897 if (!is_linked()) {
898 link_class_impl(CHECK);
899 }
900 }
901
902 // Called to verify that a class can link during initialization, without
903 // throwing a VerifyError.
904 bool InstanceKlass::link_class_or_fail(TRAPS) {
905 assert(is_loaded(), "must be loaded");
906 if (!is_linked()) {
907 link_class_impl(CHECK_false);
908 }
909 return is_linked();
910 }
911
912 bool InstanceKlass::link_class_impl(TRAPS) {
913 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
914 // This is for CDS static dump only -- we use the in_error_state to indicate that
915 // the class has failed verification. Throwing the NoClassDefFoundError here is just
916 // a convenient way to stop repeat attempts to verify the same (bad) class.
917 //
918 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
919 // if we are executing Java code. This is not a problem for CDS dumping phase since
920 // it doesn't execute any Java code.
921 ResourceMark rm(THREAD);
922 // Names are all known to be < 64k so we know this formatted message is not excessively large.
923 Exceptions::fthrow(THREAD_AND_LOCATION,
924 vmSymbols::java_lang_NoClassDefFoundError(),
925 "Class %s, or one of its supertypes, failed class initialization",
926 external_name());
927 return false;
928 }
929 // return if already verified
930 if (is_linked()) {
931 return true;
932 }
933
934 // Timing
935 // timer handles recursion
936 JavaThread* jt = THREAD;
937
938 // link super class before linking this class
939 Klass* super_klass = super();
940 if (super_klass != nullptr) {
941 if (super_klass->is_interface()) { // check if super class is an interface
942 ResourceMark rm(THREAD);
943 // Names are all known to be < 64k so we know this formatted message is not excessively large.
944 Exceptions::fthrow(
945 THREAD_AND_LOCATION,
946 vmSymbols::java_lang_IncompatibleClassChangeError(),
947 "class %s has interface %s as super class",
948 external_name(),
949 super_klass->external_name()
950 );
951 return false;
952 }
953
954 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
955 ik_super->link_class_impl(CHECK_false);
956 }
957
958 // link all interfaces implemented by this class before linking this class
959 Array<InstanceKlass*>* interfaces = local_interfaces();
960 int num_interfaces = interfaces->length();
961 for (int index = 0; index < num_interfaces; index++) {
962 InstanceKlass* interk = interfaces->at(index);
963 interk->link_class_impl(CHECK_false);
964 }
965
966 // in case the class is linked in the process of linking its superclasses
967 if (is_linked()) {
968 return true;
969 }
970
971 // trace only the link time for this klass that includes
972 // the verification time
973 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
974 ClassLoader::perf_class_link_selftime(),
975 ClassLoader::perf_classes_linked(),
976 jt->get_thread_stat()->perf_recursion_counts_addr(),
977 jt->get_thread_stat()->perf_timers_addr(),
978 PerfClassTraceTime::CLASS_LINK);
979
980 // verification & rewriting
981 {
982 HandleMark hm(THREAD);
983 Handle h_init_lock(THREAD, init_lock());
984 ObjectLocker ol(h_init_lock, jt);
985 // rewritten will have been set if loader constraint error found
986 // on an earlier link attempt
987 // don't verify or rewrite if already rewritten
988 //
989
990 if (!is_linked()) {
991 if (!is_rewritten()) {
992 if (is_shared()) {
993 assert(!verified_at_dump_time(), "must be");
994 }
995 {
996 bool verify_ok = verify_code(THREAD);
997 if (!verify_ok) {
998 return false;
999 }
1000 }
1001
1002 // Just in case a side-effect of verify linked this class already
1003 // (which can sometimes happen since the verifier loads classes
1004 // using custom class loaders, which are free to initialize things)
1005 if (is_linked()) {
1006 return true;
1007 }
1008
1009 // also sets rewritten
1010 rewrite_class(CHECK_false);
1011 } else if (is_shared()) {
1012 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1013 }
1014
1015 // relocate jsrs and link methods after they are all rewritten
1016 link_methods(CHECK_false);
1017
1018 // Initialize the vtable and interface table after
1019 // methods have been rewritten since rewrite may
1020 // fabricate new Method*s.
1021 // also does loader constraint checking
1022 //
1023 // initialize_vtable and initialize_itable need to be rerun
1024 // for a shared class if
1025 // 1) the class is loaded by custom class loader or
1026 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1027 // 3) the class was not verified during dump time
1028 bool need_init_table = true;
1029 if (is_shared() && verified_at_dump_time() &&
1030 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1031 need_init_table = false;
1032 }
1033 if (need_init_table) {
1034 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1035 itable().initialize_itable_and_check_constraints(CHECK_false);
1036 }
1037 #ifdef ASSERT
1038 vtable().verify(tty, true);
1039 // In case itable verification is ever added.
1040 // itable().verify(tty, true);
1041 #endif
1042 if (Universe::is_fully_initialized()) {
1043 DeoptimizationScope deopt_scope;
1044 {
1045 // Now mark all code that assumes the class is not linked.
1046 // Set state under the Compile_lock also.
1047 MutexLocker ml(THREAD, Compile_lock);
1048
1049 set_init_state(linked);
1050 CodeCache::mark_dependents_on(&deopt_scope, this);
1051 }
1052 // Perform the deopt handshake outside Compile_lock.
1053 deopt_scope.deoptimize_marked();
1054 } else {
1055 set_init_state(linked);
1056 }
1057 if (JvmtiExport::should_post_class_prepare()) {
1058 JvmtiExport::post_class_prepare(THREAD, this);
1059 }
1060 }
1061 }
1062 return true;
1063 }
1064
1065 // Rewrite the byte codes of all of the methods of a class.
1066 // The rewriter must be called exactly once. Rewriting must happen after
1067 // verification but before the first method of the class is executed.
1068 void InstanceKlass::rewrite_class(TRAPS) {
1069 assert(is_loaded(), "must be loaded");
1070 if (is_rewritten()) {
1071 assert(is_shared(), "rewriting an unshared class?");
1072 return;
1073 }
1074 Rewriter::rewrite(this, CHECK);
1075 set_rewritten();
1076 }
1077
1078 // Now relocate and link method entry points after class is rewritten.
1079 // This is outside is_rewritten flag. In case of an exception, it can be
1080 // executed more than once.
1081 void InstanceKlass::link_methods(TRAPS) {
1082 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1083
1084 int len = methods()->length();
1085 for (int i = len-1; i >= 0; i--) {
1086 methodHandle m(THREAD, methods()->at(i));
1087 RuntimeUpcalls::install_upcalls(m);
1088
1089 // Set up method entry points for compiler and interpreter .
1090 m->link_method(m, CHECK);
1091 }
1092 }
1093
1094 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1095 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1096 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1097 for (int i = 0; i < local_interfaces()->length(); ++i) {
1098 InstanceKlass* ik = local_interfaces()->at(i);
1099
1100 // Initialization is depth first search ie. we start with top of the inheritance tree
1101 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1102 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1103 if (ik->has_nonstatic_concrete_methods()) {
1104 ik->initialize_super_interfaces(CHECK);
1105 }
1106
1107 // Only initialize() interfaces that "declare" concrete methods.
1108 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1109 ik->initialize(CHECK);
1110 }
1111 }
1112 }
1113
1114 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1115 static InitializationErrorTable* _initialization_error_table;
1116
1117 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1118 // Create the same exception with a message indicating the thread name,
1119 // and the StackTraceElements.
1120 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1121 ResourceMark rm(current);
1122 if (init_error.is_null()) {
1123 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1124
1125 // We failed to create the new exception, most likely due to either out-of-memory or
1126 // a stackoverflow error. If the original exception was either of those then we save
1127 // the shared, pre-allocated, stackless, instance of that exception.
1128 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1129 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1130 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1131 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1132 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1133 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1134 } else {
1135 return;
1136 }
1137 }
1138
1139 MutexLocker ml(current, ClassInitError_lock);
1140 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1141 bool created;
1142 if (_initialization_error_table == nullptr) {
1143 _initialization_error_table = new (mtClass) InitializationErrorTable();
1144 }
1145 _initialization_error_table->put_if_absent(this, elem, &created);
1146 assert(created, "Initialization is single threaded");
1147 log_trace(class, init)("Initialization error added for class %s", external_name());
1148 }
1149
1150 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1151 MutexLocker ml(current, ClassInitError_lock);
1152 if (_initialization_error_table == nullptr) {
1153 return nullptr;
1154 }
1155 OopHandle* h = _initialization_error_table->get(this);
1156 return (h != nullptr) ? h->resolve() : nullptr;
1157 }
1158
1159 // Need to remove entries for unloaded classes.
1160 void InstanceKlass::clean_initialization_error_table() {
1161 struct InitErrorTableCleaner {
1162 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1163 if (!ik->is_loader_alive()) {
1164 h.release(Universe::vm_global());
1165 return true;
1166 } else {
1167 return false;
1168 }
1169 }
1170 };
1171
1172 assert_locked_or_safepoint(ClassInitError_lock);
1173 InitErrorTableCleaner cleaner;
1174 if (_initialization_error_table != nullptr) {
1175 _initialization_error_table->unlink(&cleaner);
1176 }
1177 }
1178
1179 void InstanceKlass::initialize_impl(TRAPS) {
1180 HandleMark hm(THREAD);
1181
1182 // Make sure klass is linked (verified) before initialization
1183 // A class could already be verified, since it has been reflected upon.
1184 link_class(CHECK);
1185
1186 DTRACE_CLASSINIT_PROBE(required, -1);
1187
1188 bool wait = false;
1189
1190 JavaThread* jt = THREAD;
1191
1192 if (ForceProfiling) {
1193 // Preallocate MDOs.
1194 for (int i = 0; i < methods()->length(); i++) {
1195 assert(!HAS_PENDING_EXCEPTION, "");
1196 methodHandle m(THREAD, methods()->at(i));
1197 Method::build_profiling_method_data(m, THREAD);
1198 if (HAS_PENDING_EXCEPTION) {
1199 ResourceMark rm;
1200 log_warning(cds)("MDO preallocation failed for %s", external_name());
1201 CLEAR_PENDING_EXCEPTION;
1202 break;
1203 }
1204 }
1205 }
1206
1207 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1208
1209 // refer to the JVM book page 47 for description of steps
1210 // Step 1
1211 {
1212 Handle h_init_lock(THREAD, init_lock());
1213 ObjectLocker ol(h_init_lock, jt);
1214
1215 // Step 2
1216 // If we were to use wait() instead of waitInterruptibly() then
1217 // we might end up throwing IE from link/symbol resolution sites
1218 // that aren't expected to throw. This would wreak havoc. See 6320309.
1219 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1220 if (debug_logging_enabled) {
1221 ResourceMark rm(jt);
1222 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1223 jt->name(), external_name(), init_thread_name());
1224 }
1225 wait = true;
1226 jt->set_class_to_be_initialized(this);
1227 ol.wait_uninterruptibly(jt);
1228 jt->set_class_to_be_initialized(nullptr);
1229 }
1230
1231 // Step 3
1232 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1233 if (debug_logging_enabled) {
1234 ResourceMark rm(jt);
1235 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1236 jt->name(), external_name());
1237 }
1238 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1239 return;
1240 }
1241
1242 // Step 4
1243 if (is_initialized()) {
1244 if (debug_logging_enabled) {
1245 ResourceMark rm(jt);
1246 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1247 jt->name(), external_name());
1248 }
1249 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1250 return;
1251 }
1252
1253 // Step 5
1254 if (is_in_error_state()) {
1255 if (debug_logging_enabled) {
1256 ResourceMark rm(jt);
1257 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1258 jt->name(), external_name());
1259 }
1260
1261 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1262 ResourceMark rm(THREAD);
1263 Handle cause(THREAD, get_initialization_error(THREAD));
1264
1265 stringStream ss;
1266 ss.print("Could not initialize class %s", external_name());
1267 if (cause.is_null()) {
1268 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1269 } else {
1270 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1271 ss.as_string(), cause);
1272 }
1273 } else {
1274
1275 // Step 6
1276 set_init_state(being_initialized);
1277 set_init_thread(jt);
1278 if (debug_logging_enabled) {
1279 ResourceMark rm(jt);
1280 log_debug(class, init)("Thread \"%s\" is initializing %s",
1281 jt->name(), external_name());
1282 }
1283 }
1284 }
1285
1286 // Step 7
1287 // Next, if C is a class rather than an interface, initialize it's super class and super
1288 // interfaces.
1289 if (!is_interface()) {
1290 Klass* super_klass = super();
1291 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1292 super_klass->initialize(THREAD);
1293 }
1294 // If C implements any interface that declares a non-static, concrete method,
1295 // the initialization of C triggers initialization of its super interfaces.
1296 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1297 // having a superinterface that declares, non-static, concrete methods
1298 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1299 initialize_super_interfaces(THREAD);
1300 }
1301
1302 // If any exceptions, complete abruptly, throwing the same exception as above.
1303 if (HAS_PENDING_EXCEPTION) {
1304 Handle e(THREAD, PENDING_EXCEPTION);
1305 CLEAR_PENDING_EXCEPTION;
1306 {
1307 EXCEPTION_MARK;
1308 add_initialization_error(THREAD, e);
1309 // Locks object, set state, and notify all waiting threads
1310 set_initialization_state_and_notify(initialization_error, THREAD);
1311 CLEAR_PENDING_EXCEPTION;
1312 }
1313 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1314 THROW_OOP(e());
1315 }
1316 }
1317
1318
1319 // Step 8
1320 {
1321 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1322 if (class_initializer() != nullptr) {
1323 // Timer includes any side effects of class initialization (resolution,
1324 // etc), but not recursive entry into call_class_initializer().
1325 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1326 ClassLoader::perf_class_init_selftime(),
1327 ClassLoader::perf_classes_inited(),
1328 jt->get_thread_stat()->perf_recursion_counts_addr(),
1329 jt->get_thread_stat()->perf_timers_addr(),
1330 PerfClassTraceTime::CLASS_CLINIT);
1331 call_class_initializer(THREAD);
1332 } else {
1333 // The elapsed time is so small it's not worth counting.
1334 if (UsePerfData) {
1335 ClassLoader::perf_classes_inited()->inc();
1336 }
1337 call_class_initializer(THREAD);
1338 }
1339 }
1340
1341 // Step 9
1342 if (!HAS_PENDING_EXCEPTION) {
1343 set_initialization_state_and_notify(fully_initialized, CHECK);
1344 debug_only(vtable().verify(tty, true);)
1345 CompilationPolicy::replay_training_at_init(this, THREAD);
1346 }
1347 else {
1348 // Step 10 and 11
1349 Handle e(THREAD, PENDING_EXCEPTION);
1350 CLEAR_PENDING_EXCEPTION;
1351 // JVMTI has already reported the pending exception
1352 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1353 JvmtiExport::clear_detected_exception(jt);
1354 {
1355 EXCEPTION_MARK;
1356 add_initialization_error(THREAD, e);
1357 set_initialization_state_and_notify(initialization_error, THREAD);
1358 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1359 // JVMTI has already reported the pending exception
1360 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1361 JvmtiExport::clear_detected_exception(jt);
1362 }
1363 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1364 if (e->is_a(vmClasses::Error_klass())) {
1365 THROW_OOP(e());
1366 } else {
1367 JavaCallArguments args(e);
1368 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1369 vmSymbols::throwable_void_signature(),
1370 &args);
1371 }
1372 }
1373 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1374 }
1375
1376 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1377 Handle h_init_lock(THREAD, init_lock());
1378 if (h_init_lock() != nullptr) {
1379 ObjectLocker ol(h_init_lock, THREAD);
1380 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1381 set_init_state(state);
1382 fence_and_clear_init_lock();
1383 ol.notify_all(CHECK);
1384 } else {
1385 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1386 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1387 set_init_state(state);
1388 }
1389 }
1390
1391 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1392 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1393 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1394 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1395
1396 DeoptimizationScope deopt_scope;
1397 {
1398 MutexLocker ml(current, Compile_lock);
1399
1400 set_init_state(InstanceKlass::loaded);
1401 // make sure init_state store is already done.
1402 // The compiler reads the hierarchy outside of the Compile_lock.
1403 // Access ordering is used to add to hierarchy.
1404
1405 // Link into hierarchy.
1406 append_to_sibling_list(); // add to superklass/sibling list
1407 process_interfaces(); // handle all "implements" declarations
1408
1409 // Now mark all code that depended on old class hierarchy.
1410 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1411 if (Universe::is_fully_initialized()) {
1412 CodeCache::mark_dependents_on(&deopt_scope, this);
1413 }
1414 }
1415 // Perform the deopt handshake outside Compile_lock.
1416 deopt_scope.deoptimize_marked();
1417 }
1418
1419
1420 InstanceKlass* InstanceKlass::implementor() const {
1421 InstanceKlass* volatile* ik = adr_implementor();
1422 if (ik == nullptr) {
1423 return nullptr;
1424 } else {
1425 // This load races with inserts, and therefore needs acquire.
1426 InstanceKlass* ikls = Atomic::load_acquire(ik);
1427 if (ikls != nullptr && !ikls->is_loader_alive()) {
1428 return nullptr; // don't return unloaded class
1429 } else {
1430 return ikls;
1431 }
1432 }
1433 }
1434
1435
1436 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1437 assert_locked_or_safepoint(Compile_lock);
1438 assert(is_interface(), "not interface");
1439 InstanceKlass* volatile* addr = adr_implementor();
1440 assert(addr != nullptr, "null addr");
1441 if (addr != nullptr) {
1442 Atomic::release_store(addr, ik);
1443 }
1444 }
1445
1446 int InstanceKlass::nof_implementors() const {
1447 InstanceKlass* ik = implementor();
1448 if (ik == nullptr) {
1449 return 0;
1450 } else if (ik != this) {
1451 return 1;
1452 } else {
1453 return 2;
1454 }
1455 }
1456
1457 // The embedded _implementor field can only record one implementor.
1458 // When there are more than one implementors, the _implementor field
1459 // is set to the interface Klass* itself. Following are the possible
1460 // values for the _implementor field:
1461 // null - no implementor
1462 // implementor Klass* - one implementor
1463 // self - more than one implementor
1464 //
1465 // The _implementor field only exists for interfaces.
1466 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1467 if (Universe::is_fully_initialized()) {
1468 assert_lock_strong(Compile_lock);
1469 }
1470 assert(is_interface(), "not interface");
1471 // Filter out my subinterfaces.
1472 // (Note: Interfaces are never on the subklass list.)
1473 if (ik->is_interface()) return;
1474
1475 // Filter out subclasses whose supers already implement me.
1476 // (Note: CHA must walk subclasses of direct implementors
1477 // in order to locate indirect implementors.)
1478 InstanceKlass* super_ik = ik->java_super();
1479 if (super_ik != nullptr && super_ik->implements_interface(this))
1480 // We only need to check one immediate superclass, since the
1481 // implements_interface query looks at transitive_interfaces.
1482 // Any supers of the super have the same (or fewer) transitive_interfaces.
1483 return;
1484
1485 InstanceKlass* iklass = implementor();
1486 if (iklass == nullptr) {
1487 set_implementor(ik);
1488 } else if (iklass != this && iklass != ik) {
1489 // There is already an implementor. Use itself as an indicator of
1490 // more than one implementors.
1491 set_implementor(this);
1492 }
1493
1494 // The implementor also implements the transitive_interfaces
1495 for (int index = 0; index < local_interfaces()->length(); index++) {
1496 local_interfaces()->at(index)->add_implementor(ik);
1497 }
1498 }
1499
1500 void InstanceKlass::init_implementor() {
1501 if (is_interface()) {
1502 set_implementor(nullptr);
1503 }
1504 }
1505
1506
1507 void InstanceKlass::process_interfaces() {
1508 // link this class into the implementors list of every interface it implements
1509 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1510 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1511 InstanceKlass* interf = local_interfaces()->at(i);
1512 assert(interf->is_interface(), "expected interface");
1513 interf->add_implementor(this);
1514 }
1515 }
1516
1517 bool InstanceKlass::can_be_primary_super_slow() const {
1518 if (is_interface())
1519 return false;
1520 else
1521 return Klass::can_be_primary_super_slow();
1522 }
1523
1524 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1525 Array<InstanceKlass*>* transitive_interfaces) {
1526 // The secondaries are the implemented interfaces.
1527 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1528 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1529 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1530 int num_secondaries = num_extra_slots + interfaces->length();
1531 if (num_secondaries == 0) {
1532 // Must share this for correct bootstrapping!
1533 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1534 return nullptr;
1535 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1536 // We will reuse the transitive interfaces list if we're certain
1537 // it's in hash order.
1538 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1539 set_secondary_supers(interfaces, bitmap);
1540 return nullptr;
1541 }
1542 // Copy transitive interfaces to a temporary growable array to be constructed
1543 // into the secondary super list with extra slots.
1544 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1545 for (int i = 0; i < interfaces->length(); i++) {
1546 secondaries->push(interfaces->at(i));
1547 }
1548 return secondaries;
1549 }
1550
1551 bool InstanceKlass::implements_interface(Klass* k) const {
1552 if (this == k) return true;
1553 assert(k->is_interface(), "should be an interface class");
1554 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1555 if (transitive_interfaces()->at(i) == k) {
1556 return true;
1557 }
1558 }
1559 return false;
1560 }
1561
1562 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1563 // Verify direct super interface
1564 if (this == k) return true;
1565 assert(k->is_interface(), "should be an interface class");
1566 for (int i = 0; i < local_interfaces()->length(); i++) {
1567 if (local_interfaces()->at(i) == k) {
1568 return true;
1569 }
1570 }
1571 return false;
1572 }
1573
1574 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1575 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1576 size_t size = objArrayOopDesc::object_size(length);
1577 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1578 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1579 /* do_zero */ true, CHECK_NULL);
1580 return o;
1581 }
1582
1583 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1584 if (TraceFinalizerRegistration) {
1585 tty->print("Registered ");
1586 i->print_value_on(tty);
1587 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1588 }
1589 instanceHandle h_i(THREAD, i);
1590 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1591 JavaValue result(T_VOID);
1592 JavaCallArguments args(h_i);
1593 methodHandle mh(THREAD, Universe::finalizer_register_method());
1594 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1595 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1596 return h_i();
1597 }
1598
1599 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1600 assert(!is_abstract() && !is_interface(), "Should not create this object");
1601 size_t size = size_helper(); // Query before forming handle.
1602 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1603 }
1604
1605 instanceOop InstanceKlass::allocate_instance(oop java_class,
1606 const char* who,
1607 TRAPS) {
1608 Klass* k = java_lang_Class::as_Klass(java_class);
1609 if (k == nullptr) {
1610 ResourceMark rm(THREAD);
1611 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1612 }
1613 InstanceKlass* ik = cast(k);
1614 ik->check_valid_for_instantiation(false, CHECK_NULL);
1615 ik->initialize(CHECK_NULL);
1616 return ik->allocate_instance(THREAD);
1617 }
1618
1619 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1620 return instanceHandle(THREAD, allocate_instance(THREAD));
1621 }
1622
1623 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1624 if (is_interface() || is_abstract()) {
1625 ResourceMark rm(THREAD);
1626 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1627 : vmSymbols::java_lang_InstantiationException(), external_name());
1628 }
1629 if (this == vmClasses::Class_klass()) {
1630 ResourceMark rm(THREAD);
1631 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1632 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1633 }
1634 }
1635
1636 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1637 // Need load-acquire for lock-free read
1638 if (array_klasses_acquire() == nullptr) {
1639
1640 // Recursively lock array allocation
1641 RecursiveLocker rl(MultiArray_lock, THREAD);
1642
1643 // Check if another thread created the array klass while we were waiting for the lock.
1644 if (array_klasses() == nullptr) {
1645 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1646 // use 'release' to pair with lock-free load
1647 release_set_array_klasses(k);
1648 }
1649 }
1650
1651 // array_klasses() will always be set at this point
1652 ObjArrayKlass* ak = array_klasses();
1653 assert(ak != nullptr, "should be set");
1654 return ak->array_klass(n, THREAD);
1655 }
1656
1657 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1658 // Need load-acquire for lock-free read
1659 ObjArrayKlass* oak = array_klasses_acquire();
1660 if (oak == nullptr) {
1661 return nullptr;
1662 } else {
1663 return oak->array_klass_or_null(n);
1664 }
1665 }
1666
1667 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1668 return array_klass(1, THREAD);
1669 }
1670
1671 ArrayKlass* InstanceKlass::array_klass_or_null() {
1672 return array_klass_or_null(1);
1673 }
1674
1675 Method* InstanceKlass::class_initializer() const {
1676 Method* clinit = find_method(
1677 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1678 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1679 return clinit;
1680 }
1681 return nullptr;
1682 }
1683
1684 void InstanceKlass::call_class_initializer(TRAPS) {
1685 if (ReplayCompiles &&
1686 (ReplaySuppressInitializers == 1 ||
1687 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1688 // Hide the existence of the initializer for the purpose of replaying the compile
1689 return;
1690 }
1691
1692 #if INCLUDE_CDS
1693 // This is needed to ensure the consistency of the archived heap objects.
1694 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1695 AOTClassInitializer::call_runtime_setup(THREAD, this);
1696 return;
1697 } else if (has_archived_enum_objs()) {
1698 assert(is_shared(), "must be");
1699 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1700 if (initialized) {
1701 return;
1702 }
1703 }
1704 #endif
1705
1706 methodHandle h_method(THREAD, class_initializer());
1707 assert(!is_initialized(), "we cannot initialize twice");
1708
1709 #if 0
1710 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1711 int init_id = log_class_init(THREAD, this);
1712 if (h_method() != nullptr) {
1713 JavaCallArguments args; // No arguments
1714 JavaValue result(T_VOID);
1715 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1716 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1717
1718 elapsedTimer timer;
1719 {
1720 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1721 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1722
1723 timer.start();
1724 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1725 timer.stop();
1726 }
1727
1728 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1729
1730 jlong bc_executed = (bc_end - bc_start);
1731 if (UsePerfData && outer == nullptr) { // outermost clinit
1732 THREAD->inc_clinit_bc_counter_value(bc_executed);
1733 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1734 }
1735
1736 THREAD->set_class_being_initialized(outer);
1737
1738 LogStreamHandle(Debug, init) log;
1739 if (log.is_enabled()) {
1740 ResourceMark rm(THREAD);
1741 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1742 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1743 if (CountBytecodes || CountBytecodesPerThread) {
1744 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1745 }
1746 name()->print_value_on(&log);
1747 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1748 p2i(THREAD), THREAD->name(), p2i(this));
1749 }
1750 }
1751 LogTarget(Info, class, init) lt;
1752 if (lt.is_enabled()) {
1753 ResourceMark rm(THREAD);
1754 LogStream ls(lt);
1755 ls.print("%d Initialized ", init_id);
1756 name()->print_value_on(&ls);
1757 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1758 h_method() == nullptr ? "(no method)" : "", p2i(this),
1759 THREAD->name());
1760 }
1761 #else
1762 static int call_class_initializer_counter = 0; // for debugging
1763 LogTarget(Info, class, init) lt;
1764 if (lt.is_enabled()) {
1765 ResourceMark rm(THREAD);
1766 LogStream ls(lt);
1767 ls.print("%d Initializing ", call_class_initializer_counter++);
1768 name()->print_value_on(&ls);
1769 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1770 h_method() == nullptr ? "(no method)" : "", p2i(this),
1771 THREAD->name());
1772 }
1773 if (h_method() != nullptr) {
1774 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1775 JavaCallArguments args; // No arguments
1776 JavaValue result(T_VOID);
1777 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1778 }
1779 #endif
1780 }
1781
1782 // If a class that implements this interface is initialized, is the JVM required
1783 // to first execute a <clinit> method declared in this interface,
1784 // or (if also_check_supers==true) any of the super types of this interface?
1785 //
1786 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1787 // an interface, then let SC be its superclass and let SI1, ..., SIn
1788 // be all superinterfaces of C (whether direct or indirect) that
1789 // declare at least one non-abstract, non-static method.
1790 //
1791 // So when an interface is initialized, it does not look at its
1792 // supers. But a proper class will ensure that all of its supers have
1793 // run their <clinit> methods, except that it disregards interfaces
1794 // that lack a non-static concrete method (i.e., a default method).
1795 // Therefore, you should probably call this method only when the
1796 // current class is a super of some proper class, not an interface.
1797 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1798 assert(is_interface(), "must be");
1799
1800 if (!has_nonstatic_concrete_methods()) {
1801 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1802 return false;
1803 }
1804
1805 // JVMS 5.5. Initialization
1806 // ...If C is an interface that declares a non-abstract,
1807 // non-static method, the initialization of a class that
1808 // implements C directly or indirectly.
1809 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1810 return true;
1811 }
1812 if (also_check_supers) {
1813 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1814 for (int i = 0; i < all_ifs->length(); ++i) {
1815 InstanceKlass* super_intf = all_ifs->at(i);
1816 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1817 return true;
1818 }
1819 }
1820 }
1821 return false;
1822 }
1823
1824 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1825 InterpreterOopMap* entry_for) {
1826 // Lazily create the _oop_map_cache at first request.
1827 // Load_acquire is needed to safely get instance published with CAS by another thread.
1828 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1829 if (oop_map_cache == nullptr) {
1830 // Try to install new instance atomically.
1831 oop_map_cache = new OopMapCache();
1832 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1833 if (other != nullptr) {
1834 // Someone else managed to install before us, ditch local copy and use the existing one.
1835 delete oop_map_cache;
1836 oop_map_cache = other;
1837 }
1838 }
1839 // _oop_map_cache is constant after init; lookup below does its own locking.
1840 oop_map_cache->lookup(method, bci, entry_for);
1841 }
1842
1843 bool InstanceKlass::contains_field_offset(int offset) {
1844 fieldDescriptor fd;
1845 return find_field_from_offset(offset, false, &fd);
1846 }
1847
1848 FieldInfo InstanceKlass::field(int index) const {
1849 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1850 if (fs.index() == index) {
1851 return fs.to_FieldInfo();
1852 }
1853 }
1854 fatal("Field not found");
1855 return FieldInfo();
1856 }
1857
1858 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1859 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1860 Symbol* f_name = fs.name();
1861 Symbol* f_sig = fs.signature();
1862 if (f_name == name && f_sig == sig) {
1863 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1864 return true;
1865 }
1866 }
1867 return false;
1868 }
1869
1870
1871 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1872 const int n = local_interfaces()->length();
1873 for (int i = 0; i < n; i++) {
1874 Klass* intf1 = local_interfaces()->at(i);
1875 assert(intf1->is_interface(), "just checking type");
1876 // search for field in current interface
1877 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1878 assert(fd->is_static(), "interface field must be static");
1879 return intf1;
1880 }
1881 // search for field in direct superinterfaces
1882 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1883 if (intf2 != nullptr) return intf2;
1884 }
1885 // otherwise field lookup fails
1886 return nullptr;
1887 }
1888
1889
1890 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1891 // search order according to newest JVM spec (5.4.3.2, p.167).
1892 // 1) search for field in current klass
1893 if (find_local_field(name, sig, fd)) {
1894 return const_cast<InstanceKlass*>(this);
1895 }
1896 // 2) search for field recursively in direct superinterfaces
1897 { Klass* intf = find_interface_field(name, sig, fd);
1898 if (intf != nullptr) return intf;
1899 }
1900 // 3) apply field lookup recursively if superclass exists
1901 { Klass* supr = super();
1902 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1903 }
1904 // 4) otherwise field lookup fails
1905 return nullptr;
1906 }
1907
1908
1909 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1910 // search order according to newest JVM spec (5.4.3.2, p.167).
1911 // 1) search for field in current klass
1912 if (find_local_field(name, sig, fd)) {
1913 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1914 }
1915 // 2) search for field recursively in direct superinterfaces
1916 if (is_static) {
1917 Klass* intf = find_interface_field(name, sig, fd);
1918 if (intf != nullptr) return intf;
1919 }
1920 // 3) apply field lookup recursively if superclass exists
1921 { Klass* supr = super();
1922 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1923 }
1924 // 4) otherwise field lookup fails
1925 return nullptr;
1926 }
1927
1928
1929 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1930 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1931 if (fs.offset() == offset) {
1932 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1933 if (fd->is_static() == is_static) return true;
1934 }
1935 }
1936 return false;
1937 }
1938
1939
1940 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1941 Klass* klass = const_cast<InstanceKlass*>(this);
1942 while (klass != nullptr) {
1943 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1944 return true;
1945 }
1946 klass = klass->super();
1947 }
1948 return false;
1949 }
1950
1951
1952 void InstanceKlass::methods_do(void f(Method* method)) {
1953 // Methods aren't stable until they are loaded. This can be read outside
1954 // a lock through the ClassLoaderData for profiling
1955 // Redefined scratch classes are on the list and need to be cleaned
1956 if (!is_loaded() && !is_scratch_class()) {
1957 return;
1958 }
1959
1960 int len = methods()->length();
1961 for (int index = 0; index < len; index++) {
1962 Method* m = methods()->at(index);
1963 assert(m->is_method(), "must be method");
1964 f(m);
1965 }
1966 }
1967
1968
1969 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1970 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1971 if (fs.access_flags().is_static()) {
1972 fieldDescriptor& fd = fs.field_descriptor();
1973 cl->do_field(&fd);
1974 }
1975 }
1976 }
1977
1978
1979 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1980 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1981 if (fs.access_flags().is_static()) {
1982 fieldDescriptor& fd = fs.field_descriptor();
1983 f(&fd, mirror, CHECK);
1984 }
1985 }
1986 }
1987
1988 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1989 InstanceKlass* super = superklass();
1990 if (super != nullptr) {
1991 super->do_nonstatic_fields(cl);
1992 }
1993 fieldDescriptor fd;
1994 int length = java_fields_count();
1995 for (int i = 0; i < length; i += 1) {
1996 fd.reinitialize(this, i);
1997 if (!fd.is_static()) {
1998 cl->do_field(&fd);
1999 }
2000 }
2001 }
2002
2003 // first in Pair is offset, second is index.
2004 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2005 return a->first - b->first;
2006 }
2007
2008 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2009 InstanceKlass* super = superklass();
2010 if (super != nullptr) {
2011 super->print_nonstatic_fields(cl);
2012 }
2013 ResourceMark rm;
2014 fieldDescriptor fd;
2015 // In DebugInfo nonstatic fields are sorted by offset.
2016 GrowableArray<Pair<int,int> > fields_sorted;
2017 int i = 0;
2018 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2019 if (!fs.access_flags().is_static()) {
2020 fd = fs.field_descriptor();
2021 Pair<int,int> f(fs.offset(), fs.index());
2022 fields_sorted.push(f);
2023 i++;
2024 }
2025 }
2026 if (i > 0) {
2027 int length = i;
2028 assert(length == fields_sorted.length(), "duh");
2029 fields_sorted.sort(compare_fields_by_offset);
2030 for (int i = 0; i < length; i++) {
2031 fd.reinitialize(this, fields_sorted.at(i).second);
2032 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2033 cl->do_field(&fd);
2034 }
2035 }
2036 }
2037
2038 #ifdef ASSERT
2039 static int linear_search(const Array<Method*>* methods,
2040 const Symbol* name,
2041 const Symbol* signature) {
2042 const int len = methods->length();
2043 for (int index = 0; index < len; index++) {
2044 const Method* const m = methods->at(index);
2045 assert(m->is_method(), "must be method");
2046 if (m->signature() == signature && m->name() == name) {
2047 return index;
2048 }
2049 }
2050 return -1;
2051 }
2052 #endif
2053
2054 bool InstanceKlass::_disable_method_binary_search = false;
2055
2056 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2057 int len = methods->length();
2058 int l = 0;
2059 int h = len - 1;
2060 while (l <= h) {
2061 Method* m = methods->at(l);
2062 if (m->name() == name) {
2063 return l;
2064 }
2065 l++;
2066 }
2067 return -1;
2068 }
2069
2070 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2071 if (_disable_method_binary_search) {
2072 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2073 // At the final stage of dynamic dumping, the methods array may not be sorted
2074 // by ascending addresses of their names, so we can't use binary search anymore.
2075 // However, methods with the same name are still laid out consecutively inside the
2076 // methods array, so let's look for the first one that matches.
2077 return linear_search(methods, name);
2078 }
2079
2080 int len = methods->length();
2081 int l = 0;
2082 int h = len - 1;
2083
2084 // methods are sorted by ascending addresses of their names, so do binary search
2085 while (l <= h) {
2086 int mid = (l + h) >> 1;
2087 Method* m = methods->at(mid);
2088 assert(m->is_method(), "must be method");
2089 int res = m->name()->fast_compare(name);
2090 if (res == 0) {
2091 return mid;
2092 } else if (res < 0) {
2093 l = mid + 1;
2094 } else {
2095 h = mid - 1;
2096 }
2097 }
2098 return -1;
2099 }
2100
2101 // find_method looks up the name/signature in the local methods array
2102 Method* InstanceKlass::find_method(const Symbol* name,
2103 const Symbol* signature) const {
2104 return find_method_impl(name, signature,
2105 OverpassLookupMode::find,
2106 StaticLookupMode::find,
2107 PrivateLookupMode::find);
2108 }
2109
2110 Method* InstanceKlass::find_method_impl(const Symbol* name,
2111 const Symbol* signature,
2112 OverpassLookupMode overpass_mode,
2113 StaticLookupMode static_mode,
2114 PrivateLookupMode private_mode) const {
2115 return InstanceKlass::find_method_impl(methods(),
2116 name,
2117 signature,
2118 overpass_mode,
2119 static_mode,
2120 private_mode);
2121 }
2122
2123 // find_instance_method looks up the name/signature in the local methods array
2124 // and skips over static methods
2125 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2126 const Symbol* name,
2127 const Symbol* signature,
2128 PrivateLookupMode private_mode) {
2129 Method* const meth = InstanceKlass::find_method_impl(methods,
2130 name,
2131 signature,
2132 OverpassLookupMode::find,
2133 StaticLookupMode::skip,
2134 private_mode);
2135 assert(((meth == nullptr) || !meth->is_static()),
2136 "find_instance_method should have skipped statics");
2137 return meth;
2138 }
2139
2140 // find_instance_method looks up the name/signature in the local methods array
2141 // and skips over static methods
2142 Method* InstanceKlass::find_instance_method(const Symbol* name,
2143 const Symbol* signature,
2144 PrivateLookupMode private_mode) const {
2145 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2146 }
2147
2148 // Find looks up the name/signature in the local methods array
2149 // and filters on the overpass, static and private flags
2150 // This returns the first one found
2151 // note that the local methods array can have up to one overpass, one static
2152 // and one instance (private or not) with the same name/signature
2153 Method* InstanceKlass::find_local_method(const Symbol* name,
2154 const Symbol* signature,
2155 OverpassLookupMode overpass_mode,
2156 StaticLookupMode static_mode,
2157 PrivateLookupMode private_mode) const {
2158 return InstanceKlass::find_method_impl(methods(),
2159 name,
2160 signature,
2161 overpass_mode,
2162 static_mode,
2163 private_mode);
2164 }
2165
2166 // Find looks up the name/signature in the local methods array
2167 // and filters on the overpass, static and private flags
2168 // This returns the first one found
2169 // note that the local methods array can have up to one overpass, one static
2170 // and one instance (private or not) with the same name/signature
2171 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2172 const Symbol* name,
2173 const Symbol* signature,
2174 OverpassLookupMode overpass_mode,
2175 StaticLookupMode static_mode,
2176 PrivateLookupMode private_mode) {
2177 return InstanceKlass::find_method_impl(methods,
2178 name,
2179 signature,
2180 overpass_mode,
2181 static_mode,
2182 private_mode);
2183 }
2184
2185 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2186 const Symbol* name,
2187 const Symbol* signature) {
2188 return InstanceKlass::find_method_impl(methods,
2189 name,
2190 signature,
2191 OverpassLookupMode::find,
2192 StaticLookupMode::find,
2193 PrivateLookupMode::find);
2194 }
2195
2196 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2197 const Symbol* name,
2198 const Symbol* signature,
2199 OverpassLookupMode overpass_mode,
2200 StaticLookupMode static_mode,
2201 PrivateLookupMode private_mode) {
2202 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2203 return hit >= 0 ? methods->at(hit): nullptr;
2204 }
2205
2206 // true if method matches signature and conforms to skipping_X conditions.
2207 static bool method_matches(const Method* m,
2208 const Symbol* signature,
2209 bool skipping_overpass,
2210 bool skipping_static,
2211 bool skipping_private) {
2212 return ((m->signature() == signature) &&
2213 (!skipping_overpass || !m->is_overpass()) &&
2214 (!skipping_static || !m->is_static()) &&
2215 (!skipping_private || !m->is_private()));
2216 }
2217
2218 // Used directly for default_methods to find the index into the
2219 // default_vtable_indices, and indirectly by find_method
2220 // find_method_index looks in the local methods array to return the index
2221 // of the matching name/signature. If, overpass methods are being ignored,
2222 // the search continues to find a potential non-overpass match. This capability
2223 // is important during method resolution to prefer a static method, for example,
2224 // over an overpass method.
2225 // There is the possibility in any _method's array to have the same name/signature
2226 // for a static method, an overpass method and a local instance method
2227 // To correctly catch a given method, the search criteria may need
2228 // to explicitly skip the other two. For local instance methods, it
2229 // is often necessary to skip private methods
2230 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2231 const Symbol* name,
2232 const Symbol* signature,
2233 OverpassLookupMode overpass_mode,
2234 StaticLookupMode static_mode,
2235 PrivateLookupMode private_mode) {
2236 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2237 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2238 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2239 const int hit = quick_search(methods, name);
2240 if (hit != -1) {
2241 const Method* const m = methods->at(hit);
2242
2243 // Do linear search to find matching signature. First, quick check
2244 // for common case, ignoring overpasses if requested.
2245 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2246 return hit;
2247 }
2248
2249 // search downwards through overloaded methods
2250 int i;
2251 for (i = hit - 1; i >= 0; --i) {
2252 const Method* const m = methods->at(i);
2253 assert(m->is_method(), "must be method");
2254 if (m->name() != name) {
2255 break;
2256 }
2257 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2258 return i;
2259 }
2260 }
2261 // search upwards
2262 for (i = hit + 1; i < methods->length(); ++i) {
2263 const Method* const m = methods->at(i);
2264 assert(m->is_method(), "must be method");
2265 if (m->name() != name) {
2266 break;
2267 }
2268 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2269 return i;
2270 }
2271 }
2272 // not found
2273 #ifdef ASSERT
2274 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2275 linear_search(methods, name, signature);
2276 assert(-1 == index, "binary search should have found entry %d", index);
2277 #endif
2278 }
2279 return -1;
2280 }
2281
2282 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2283 return find_method_by_name(methods(), name, end);
2284 }
2285
2286 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2287 const Symbol* name,
2288 int* end_ptr) {
2289 assert(end_ptr != nullptr, "just checking");
2290 int start = quick_search(methods, name);
2291 int end = start + 1;
2292 if (start != -1) {
2293 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2294 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2295 *end_ptr = end;
2296 return start;
2297 }
2298 return -1;
2299 }
2300
2301 // uncached_lookup_method searches both the local class methods array and all
2302 // superclasses methods arrays, skipping any overpass methods in superclasses,
2303 // and possibly skipping private methods.
2304 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2305 const Symbol* signature,
2306 OverpassLookupMode overpass_mode,
2307 PrivateLookupMode private_mode) const {
2308 OverpassLookupMode overpass_local_mode = overpass_mode;
2309 const Klass* klass = this;
2310 while (klass != nullptr) {
2311 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2312 signature,
2313 overpass_local_mode,
2314 StaticLookupMode::find,
2315 private_mode);
2316 if (method != nullptr) {
2317 return method;
2318 }
2319 klass = klass->super();
2320 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2321 }
2322 return nullptr;
2323 }
2324
2325 #ifdef ASSERT
2326 // search through class hierarchy and return true if this class or
2327 // one of the superclasses was redefined
2328 bool InstanceKlass::has_redefined_this_or_super() const {
2329 const Klass* klass = this;
2330 while (klass != nullptr) {
2331 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2332 return true;
2333 }
2334 klass = klass->super();
2335 }
2336 return false;
2337 }
2338 #endif
2339
2340 // lookup a method in the default methods list then in all transitive interfaces
2341 // Do NOT return private or static methods
2342 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2343 Symbol* signature) const {
2344 Method* m = nullptr;
2345 if (default_methods() != nullptr) {
2346 m = find_method(default_methods(), name, signature);
2347 }
2348 // Look up interfaces
2349 if (m == nullptr) {
2350 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2351 }
2352 return m;
2353 }
2354
2355 // lookup a method in all the interfaces that this class implements
2356 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2357 // They should only be found in the initial InterfaceMethodRef
2358 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2359 Symbol* signature,
2360 DefaultsLookupMode defaults_mode) const {
2361 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2362 int num_ifs = all_ifs->length();
2363 InstanceKlass *ik = nullptr;
2364 for (int i = 0; i < num_ifs; i++) {
2365 ik = all_ifs->at(i);
2366 Method* m = ik->lookup_method(name, signature);
2367 if (m != nullptr && m->is_public() && !m->is_static() &&
2368 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2369 return m;
2370 }
2371 }
2372 return nullptr;
2373 }
2374
2375 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2376 :_st(st), _verbose(verbose) {
2377 ResourceMark rm;
2378 _st->print("%-18s ", "KlassAddr");
2379 _st->print("%-4s ", "Size");
2380 _st->print("%-20s ", "State");
2381 _st->print("%-7s ", "Flags");
2382 _st->print("%-5s ", "ClassName");
2383 _st->cr();
2384 }
2385
2386 void PrintClassClosure::do_klass(Klass* k) {
2387 ResourceMark rm;
2388 // klass pointer
2389 _st->print(PTR_FORMAT " ", p2i(k));
2390 // klass size
2391 _st->print("%4d ", k->size());
2392 // initialization state
2393 if (k->is_instance_klass()) {
2394 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2395 } else {
2396 _st->print("%-20s ","");
2397 }
2398 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2399 char buf[10];
2400 int i = 0;
2401 if (k->has_finalizer()) buf[i++] = 'F';
2402 if (k->is_instance_klass()) {
2403 InstanceKlass* ik = InstanceKlass::cast(k);
2404 if (ik->has_final_method()) buf[i++] = 'f';
2405 if (ik->is_rewritten()) buf[i++] = 'W';
2406 if (ik->is_contended()) buf[i++] = 'C';
2407 if (ik->has_been_redefined()) buf[i++] = 'R';
2408 if (ik->is_shared()) buf[i++] = 'S';
2409 }
2410 buf[i++] = '\0';
2411 _st->print("%-7s ", buf);
2412 // klass name
2413 _st->print("%-5s ", k->external_name());
2414 // end
2415 _st->cr();
2416 if (_verbose) {
2417 k->print_on(_st);
2418 }
2419 }
2420
2421 /* jni_id_for for jfieldIds only */
2422 JNIid* InstanceKlass::jni_id_for(int offset) {
2423 MutexLocker ml(JfieldIdCreation_lock);
2424 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2425 if (probe == nullptr) {
2426 // Allocate new static field identifier
2427 probe = new JNIid(this, offset, jni_ids());
2428 set_jni_ids(probe);
2429 }
2430 return probe;
2431 }
2432
2433 u2 InstanceKlass::enclosing_method_data(int offset) const {
2434 const Array<jushort>* const inner_class_list = inner_classes();
2435 if (inner_class_list == nullptr) {
2436 return 0;
2437 }
2438 const int length = inner_class_list->length();
2439 if (length % inner_class_next_offset == 0) {
2440 return 0;
2441 }
2442 const int index = length - enclosing_method_attribute_size;
2443 assert(offset < enclosing_method_attribute_size, "invalid offset");
2444 return inner_class_list->at(index + offset);
2445 }
2446
2447 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2448 u2 method_index) {
2449 Array<jushort>* inner_class_list = inner_classes();
2450 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2451 int length = inner_class_list->length();
2452 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2453 int index = length - enclosing_method_attribute_size;
2454 inner_class_list->at_put(
2455 index + enclosing_method_class_index_offset, class_index);
2456 inner_class_list->at_put(
2457 index + enclosing_method_method_index_offset, method_index);
2458 }
2459 }
2460
2461 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2462 if (method->is_old() && !method->is_obsolete()) {
2463 // If the method passed in is old (but not obsolete), use the current version.
2464 method = method_with_idnum((int)idnum);
2465 assert(method != nullptr, "old and but not obsolete, so should exist");
2466 }
2467 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2468 Atomic::release_store(&jmeths[idnum + 1], new_id);
2469 return new_id;
2470 }
2471
2472 // Lookup or create a jmethodID.
2473 // This code is called by the VMThread and JavaThreads so the
2474 // locking has to be done very carefully to avoid deadlocks
2475 // and/or other cache consistency problems.
2476 //
2477 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2478 Method* method = method_h();
2479 int idnum = method->method_idnum();
2480 jmethodID* jmeths = methods_jmethod_ids_acquire();
2481
2482 // We use a double-check locking idiom here because this cache is
2483 // performance sensitive. In the normal system, this cache only
2484 // transitions from null to non-null which is safe because we use
2485 // release_set_methods_jmethod_ids() to advertise the new cache.
2486 // A partially constructed cache should never be seen by a racing
2487 // thread. We also use release_store() to save a new jmethodID
2488 // in the cache so a partially constructed jmethodID should never be
2489 // seen either. Cache reads of existing jmethodIDs proceed without a
2490 // lock, but cache writes of a new jmethodID requires uniqueness and
2491 // creation of the cache itself requires no leaks so a lock is
2492 // acquired in those two cases.
2493 //
2494 // If the RedefineClasses() API has been used, then this cache grows
2495 // in the redefinition safepoint.
2496
2497 if (jmeths == nullptr) {
2498 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2499 jmeths = methods_jmethod_ids_acquire();
2500 // Still null?
2501 if (jmeths == nullptr) {
2502 size_t size = idnum_allocated_count();
2503 assert(size > (size_t)idnum, "should already have space");
2504 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2505 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2506 // cache size is stored in element[0], other elements offset by one
2507 jmeths[0] = (jmethodID)size;
2508 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2509
2510 // publish jmeths
2511 release_set_methods_jmethod_ids(jmeths);
2512 return new_id;
2513 }
2514 }
2515
2516 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2517 if (id == nullptr) {
2518 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2519 id = jmeths[idnum + 1];
2520 // Still null?
2521 if (id == nullptr) {
2522 return update_jmethod_id(jmeths, method, idnum);
2523 }
2524 }
2525 return id;
2526 }
2527
2528 void InstanceKlass::update_methods_jmethod_cache() {
2529 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2530 jmethodID* cache = _methods_jmethod_ids;
2531 if (cache != nullptr) {
2532 size_t size = idnum_allocated_count();
2533 size_t old_size = (size_t)cache[0];
2534 if (old_size < size + 1) {
2535 // Allocate a larger one and copy entries to the new one.
2536 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2537 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2538 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2539 // The cache size is stored in element[0]; the other elements are offset by one.
2540 new_cache[0] = (jmethodID)size;
2541
2542 for (int i = 1; i <= (int)old_size; i++) {
2543 new_cache[i] = cache[i];
2544 }
2545 _methods_jmethod_ids = new_cache;
2546 FREE_C_HEAP_ARRAY(jmethodID, cache);
2547 }
2548 }
2549 }
2550
2551 // Figure out how many jmethodIDs haven't been allocated, and make
2552 // sure space for them is pre-allocated. This makes getting all
2553 // method ids much, much faster with classes with more than 8
2554 // methods, and has a *substantial* effect on performance with jvmti
2555 // code that loads all jmethodIDs for all classes.
2556 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2557 int new_jmeths = 0;
2558 int length = methods()->length();
2559 for (int index = start_offset; index < length; index++) {
2560 Method* m = methods()->at(index);
2561 jmethodID id = m->find_jmethod_id_or_null();
2562 if (id == nullptr) {
2563 new_jmeths++;
2564 }
2565 }
2566 if (new_jmeths != 0) {
2567 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2568 }
2569 }
2570
2571 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2572 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2573 int idnum = method->method_idnum();
2574 jmethodID* jmeths = methods_jmethod_ids_acquire();
2575 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2576 }
2577
2578 inline DependencyContext InstanceKlass::dependencies() {
2579 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2580 return dep_context;
2581 }
2582
2583 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2584 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2585 }
2586
2587 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2588 dependencies().add_dependent_nmethod(nm);
2589 }
2590
2591 void InstanceKlass::clean_dependency_context() {
2592 dependencies().clean_unloading_dependents();
2593 }
2594
2595 #ifndef PRODUCT
2596 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2597 dependencies().print_dependent_nmethods(verbose);
2598 }
2599
2600 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2601 return dependencies().is_dependent_nmethod(nm);
2602 }
2603 #endif //PRODUCT
2604
2605 void InstanceKlass::clean_weak_instanceklass_links() {
2606 clean_implementors_list();
2607 clean_method_data();
2608 }
2609
2610 void InstanceKlass::clean_implementors_list() {
2611 assert(is_loader_alive(), "this klass should be live");
2612 if (is_interface()) {
2613 assert (ClassUnloading, "only called for ClassUnloading");
2614 for (;;) {
2615 // Use load_acquire due to competing with inserts
2616 InstanceKlass* volatile* iklass = adr_implementor();
2617 assert(iklass != nullptr, "Klass must not be null");
2618 InstanceKlass* impl = Atomic::load_acquire(iklass);
2619 if (impl != nullptr && !impl->is_loader_alive()) {
2620 // null this field, might be an unloaded instance klass or null
2621 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2622 // Successfully unlinking implementor.
2623 if (log_is_enabled(Trace, class, unload)) {
2624 ResourceMark rm;
2625 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2626 }
2627 return;
2628 }
2629 } else {
2630 return;
2631 }
2632 }
2633 }
2634 }
2635
2636 void InstanceKlass::clean_method_data() {
2637 for (int m = 0; m < methods()->length(); m++) {
2638 MethodData* mdo = methods()->at(m)->method_data();
2639 if (mdo != nullptr) {
2640 mdo->clean_method_data(/*always_clean*/false);
2641 }
2642 }
2643 }
2644
2645 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2646 Klass::metaspace_pointers_do(it);
2647
2648 if (log_is_enabled(Trace, cds)) {
2649 ResourceMark rm;
2650 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2651 }
2652
2653 it->push(&_annotations);
2654 it->push((Klass**)&_array_klasses);
2655 if (!is_rewritten()) {
2656 it->push(&_constants, MetaspaceClosure::_writable);
2657 } else {
2658 it->push(&_constants);
2659 }
2660 it->push(&_inner_classes);
2661 #if INCLUDE_JVMTI
2662 it->push(&_previous_versions);
2663 #endif
2664 #if INCLUDE_CDS
2665 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2666 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2667 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2668 // The length check on the _methods is necessary because classes which don't have any
2669 // methods share the Universe::_the_empty_method_array which is in the RO region.
2670 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2671 // To handle jsr bytecode, new Method* maybe stored into _methods
2672 it->push(&_methods, MetaspaceClosure::_writable);
2673 } else {
2674 #endif
2675 it->push(&_methods);
2676 #if INCLUDE_CDS
2677 }
2678 #endif
2679 it->push(&_default_methods);
2680 it->push(&_local_interfaces);
2681 it->push(&_transitive_interfaces);
2682 it->push(&_method_ordering);
2683 if (!is_rewritten()) {
2684 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2685 } else {
2686 it->push(&_default_vtable_indices);
2687 }
2688
2689 it->push(&_fieldinfo_stream);
2690 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2691 it->push(&_fields_status, MetaspaceClosure::_writable);
2692
2693 if (itable_length() > 0) {
2694 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2695 int method_table_offset_in_words = ioe->offset()/wordSize;
2696 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2697
2698 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2699 / itableOffsetEntry::size();
2700
2701 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2702 if (ioe->interface_klass() != nullptr) {
2703 it->push(ioe->interface_klass_addr());
2704 itableMethodEntry* ime = ioe->first_method_entry(this);
2705 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2706 for (int index = 0; index < n; index ++) {
2707 it->push(ime[index].method_addr());
2708 }
2709 }
2710 }
2711 }
2712
2713 it->push(&_nest_host);
2714 it->push(&_nest_members);
2715 it->push(&_permitted_subclasses);
2716 it->push(&_record_components);
2717 }
2718
2719 #if INCLUDE_CDS
2720 void InstanceKlass::remove_unshareable_info() {
2721 if (is_linked()) {
2722 assert(can_be_verified_at_dumptime(), "must be");
2723 // Remember this so we can avoid walking the hierarchy at runtime.
2724 set_verified_at_dump_time();
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_invokedynamic() && 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 (is_shared_unregistered_class()) {
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 int InstanceKlass::shared_class_loader_type() const {
2929 if (is_shared_boot_class()) {
2930 return ClassLoader::BOOT_LOADER;
2931 } else if (is_shared_platform_class()) {
2932 return ClassLoader::PLATFORM_LOADER;
2933 } else if (is_shared_app_class()) {
2934 return ClassLoader::APP_LOADER;
2935 } else {
2936 return ClassLoader::OTHER;
2937 }
2938 }
2939
2940 #endif // INCLUDE_CDS
2941
2942 #if INCLUDE_JVMTI
2943 static void clear_all_breakpoints(Method* m) {
2944 m->clear_all_breakpoints();
2945 }
2946 #endif
2947
2948 void InstanceKlass::unload_class(InstanceKlass* ik) {
2949
2950 if (ik->is_scratch_class()) {
2951 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2952 return;
2953 }
2954 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2955
2956 // Release dependencies.
2957 ik->dependencies().remove_all_dependents();
2958
2959 // notify the debugger
2960 if (JvmtiExport::should_post_class_unload()) {
2961 JvmtiExport::post_class_unload(ik);
2962 }
2963
2964 // notify ClassLoadingService of class unload
2965 ClassLoadingService::notify_class_unloaded(ik);
2966
2967 SystemDictionaryShared::handle_class_unloading(ik);
2968
2969 if (log_is_enabled(Info, class, unload)) {
2970 ResourceMark rm;
2971 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2972 }
2973
2974 Events::log_class_unloading(Thread::current(), ik);
2975
2976 #if INCLUDE_JFR
2977 assert(ik != nullptr, "invariant");
2978 EventClassUnload event;
2979 event.set_unloadedClass(ik);
2980 event.set_definingClassLoader(ik->class_loader_data());
2981 event.commit();
2982 #endif
2983 }
2984
2985 static void method_release_C_heap_structures(Method* m) {
2986 m->release_C_heap_structures();
2987 }
2988
2989 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2990 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2991 // Clean up C heap
2992 Klass::release_C_heap_structures();
2993
2994 // Deallocate and call destructors for MDO mutexes
2995 if (release_sub_metadata) {
2996 methods_do(method_release_C_heap_structures);
2997 }
2998
2999 // Deallocate oop map cache
3000 if (_oop_map_cache != nullptr) {
3001 delete _oop_map_cache;
3002 _oop_map_cache = nullptr;
3003 }
3004
3005 // Deallocate JNI identifiers for jfieldIDs
3006 JNIid::deallocate(jni_ids());
3007 set_jni_ids(nullptr);
3008
3009 jmethodID* jmeths = methods_jmethod_ids_acquire();
3010 if (jmeths != nullptr) {
3011 release_set_methods_jmethod_ids(nullptr);
3012 FreeHeap(jmeths);
3013 }
3014
3015 assert(_dep_context == nullptr,
3016 "dependencies should already be cleaned");
3017
3018 #if INCLUDE_JVMTI
3019 // Deallocate breakpoint records
3020 if (breakpoints() != nullptr) {
3021 methods_do(clear_all_breakpoints);
3022 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3023 }
3024
3025 // deallocate the cached class file
3026 if (_cached_class_file != nullptr) {
3027 os::free(_cached_class_file);
3028 _cached_class_file = nullptr;
3029 }
3030 #endif
3031
3032 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3033
3034 if (release_sub_metadata) {
3035 constants()->release_C_heap_structures();
3036 }
3037 }
3038
3039 // The constant pool is on stack if any of the methods are executing or
3040 // referenced by handles.
3041 bool InstanceKlass::on_stack() const {
3042 return _constants->on_stack();
3043 }
3044
3045 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3046 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3047 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3048
3049 // minor and major version numbers of class file
3050 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3051 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3052 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3053 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3054
3055 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3056 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3057 if (ik->constants()->version() == version) {
3058 return ik;
3059 }
3060 }
3061 return nullptr;
3062 }
3063
3064 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3065 if (array == nullptr) {
3066 _source_debug_extension = nullptr;
3067 } else {
3068 // Adding one to the attribute length in order to store a null terminator
3069 // character could cause an overflow because the attribute length is
3070 // already coded with an u4 in the classfile, but in practice, it's
3071 // unlikely to happen.
3072 assert((length+1) > length, "Overflow checking");
3073 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3074 for (int i = 0; i < length; i++) {
3075 sde[i] = array[i];
3076 }
3077 sde[length] = '\0';
3078 _source_debug_extension = sde;
3079 }
3080 }
3081
3082 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3083 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3084 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3085
3086 const char* InstanceKlass::signature_name() const {
3087
3088 // Get the internal name as a c string
3089 const char* src = (const char*) (name()->as_C_string());
3090 const int src_length = (int)strlen(src);
3091
3092 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3093
3094 // Add L as type indicator
3095 int dest_index = 0;
3096 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3097
3098 // Add the actual class name
3099 for (int src_index = 0; src_index < src_length; ) {
3100 dest[dest_index++] = src[src_index++];
3101 }
3102
3103 if (is_hidden()) { // Replace the last '+' with a '.'.
3104 for (int index = (int)src_length; index > 0; index--) {
3105 if (dest[index] == '+') {
3106 dest[index] = JVM_SIGNATURE_DOT;
3107 break;
3108 }
3109 }
3110 }
3111
3112 // Add the semicolon and the null
3113 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3114 dest[dest_index] = '\0';
3115 return dest;
3116 }
3117
3118 ModuleEntry* InstanceKlass::module() const {
3119 if (is_hidden() &&
3120 in_unnamed_package() &&
3121 class_loader_data()->has_class_mirror_holder()) {
3122 // For a non-strong hidden class defined to an unnamed package,
3123 // its (class held) CLD will not have an unnamed module created for it.
3124 // Two choices to find the correct ModuleEntry:
3125 // 1. If hidden class is within a nest, use nest host's module
3126 // 2. Find the unnamed module off from the class loader
3127 // For now option #2 is used since a nest host is not set until
3128 // after the instance class is created in jvm_lookup_define_class().
3129 if (class_loader_data()->is_boot_class_loader_data()) {
3130 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3131 } else {
3132 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3133 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3134 return java_lang_Module::module_entry(module);
3135 }
3136 }
3137
3138 // Class is in a named package
3139 if (!in_unnamed_package()) {
3140 return _package_entry->module();
3141 }
3142
3143 // Class is in an unnamed package, return its loader's unnamed module
3144 return class_loader_data()->unnamed_module();
3145 }
3146
3147 bool InstanceKlass::in_javabase_module() const {
3148 return module()->name() == vmSymbols::java_base();
3149 }
3150
3151 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3152
3153 // ensure java/ packages only loaded by boot or platform builtin loaders
3154 // not needed for shared class since CDS does not archive prohibited classes.
3155 if (!is_shared()) {
3156 check_prohibited_package(name(), loader_data, CHECK);
3157 }
3158
3159 if (is_shared() && _package_entry != nullptr) {
3160 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3161 // we can use the saved package
3162 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3163 return;
3164 } else {
3165 _package_entry = nullptr;
3166 }
3167 }
3168
3169 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3170 // it returns, so we need to decrement it when the current function exits.
3171 TempNewSymbol from_class_name =
3172 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3173
3174 Symbol* pkg_name;
3175 if (pkg_entry != nullptr) {
3176 pkg_name = pkg_entry->name();
3177 } else {
3178 pkg_name = from_class_name;
3179 }
3180
3181 if (pkg_name != nullptr && loader_data != nullptr) {
3182
3183 // Find in class loader's package entry table.
3184 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3185
3186 // If the package name is not found in the loader's package
3187 // entry table, it is an indication that the package has not
3188 // been defined. Consider it defined within the unnamed module.
3189 if (_package_entry == nullptr) {
3190
3191 if (!ModuleEntryTable::javabase_defined()) {
3192 // Before java.base is defined during bootstrapping, define all packages in
3193 // the java.base module. If a non-java.base package is erroneously placed
3194 // in the java.base module it will be caught later when java.base
3195 // is defined by ModuleEntryTable::verify_javabase_packages check.
3196 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3197 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3198 } else {
3199 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3200 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3201 }
3202
3203 // A package should have been successfully created
3204 DEBUG_ONLY(ResourceMark rm(THREAD));
3205 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3206 name()->as_C_string(), loader_data->loader_name_and_id());
3207 }
3208
3209 if (log_is_enabled(Debug, module)) {
3210 ResourceMark rm(THREAD);
3211 ModuleEntry* m = _package_entry->module();
3212 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3213 external_name(),
3214 pkg_name->as_C_string(),
3215 loader_data->loader_name_and_id(),
3216 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3217 }
3218 } else {
3219 ResourceMark rm(THREAD);
3220 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3221 external_name(),
3222 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3223 UNNAMED_MODULE);
3224 }
3225 }
3226
3227 // Function set_classpath_index ensures that for a non-null _package_entry
3228 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3229 // It then sets the classpath_index in the package entry record.
3230 //
3231 // The classpath_index field is used to find the entry on the boot loader class
3232 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3233 // in an unnamed module. It is also used to indicate (for all packages whose
3234 // classes are loaded by the boot loader) that at least one of the package's
3235 // classes has been loaded.
3236 void InstanceKlass::set_classpath_index(s2 path_index) {
3237 if (_package_entry != nullptr) {
3238 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3239 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3240 assert(path_index != -1, "Unexpected classpath_index");
3241 _package_entry->set_classpath_index(path_index);
3242 }
3243 }
3244
3245 // different versions of is_same_class_package
3246
3247 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3248 oop classloader1 = this->class_loader();
3249 PackageEntry* classpkg1 = this->package();
3250 if (class2->is_objArray_klass()) {
3251 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3252 }
3253
3254 oop classloader2;
3255 PackageEntry* classpkg2;
3256 if (class2->is_instance_klass()) {
3257 classloader2 = class2->class_loader();
3258 classpkg2 = class2->package();
3259 } else {
3260 assert(class2->is_typeArray_klass(), "should be type array");
3261 classloader2 = nullptr;
3262 classpkg2 = nullptr;
3263 }
3264
3265 // Same package is determined by comparing class loader
3266 // and package entries. Both must be the same. This rule
3267 // applies even to classes that are defined in the unnamed
3268 // package, they still must have the same class loader.
3269 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3270 return true;
3271 }
3272
3273 return false;
3274 }
3275
3276 // return true if this class and other_class are in the same package. Classloader
3277 // and classname information is enough to determine a class's package
3278 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3279 const Symbol* other_class_name) const {
3280 if (class_loader() != other_class_loader) {
3281 return false;
3282 }
3283 if (name()->fast_compare(other_class_name) == 0) {
3284 return true;
3285 }
3286
3287 {
3288 ResourceMark rm;
3289
3290 bool bad_class_name = false;
3291 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3292 if (bad_class_name) {
3293 return false;
3294 }
3295 // Check that package_from_class_name() returns null, not "", if there is no package.
3296 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3297
3298 const Symbol* const this_package_name =
3299 this->package() != nullptr ? this->package()->name() : nullptr;
3300
3301 if (this_package_name == nullptr || other_pkg == nullptr) {
3302 // One of the two doesn't have a package. Only return true if the other
3303 // one also doesn't have a package.
3304 return this_package_name == other_pkg;
3305 }
3306
3307 // Check if package is identical
3308 return this_package_name->fast_compare(other_pkg) == 0;
3309 }
3310 }
3311
3312 static bool is_prohibited_package_slow(Symbol* class_name) {
3313 // Caller has ResourceMark
3314 int length;
3315 jchar* unicode = class_name->as_unicode(length);
3316 return (length >= 5 &&
3317 unicode[0] == 'j' &&
3318 unicode[1] == 'a' &&
3319 unicode[2] == 'v' &&
3320 unicode[3] == 'a' &&
3321 unicode[4] == '/');
3322 }
3323
3324 // Only boot and platform class loaders can define classes in "java/" packages.
3325 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3326 ClassLoaderData* loader_data,
3327 TRAPS) {
3328 if (!loader_data->is_boot_class_loader_data() &&
3329 !loader_data->is_platform_class_loader_data() &&
3330 class_name != nullptr && class_name->utf8_length() >= 5) {
3331 ResourceMark rm(THREAD);
3332 bool prohibited;
3333 const u1* base = class_name->base();
3334 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3335 prohibited = is_prohibited_package_slow(class_name);
3336 } else {
3337 char* name = class_name->as_C_string();
3338 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3339 }
3340 if (prohibited) {
3341 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3342 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3343 char* name = pkg_name->as_C_string();
3344 const char* class_loader_name = loader_data->loader_name_and_id();
3345 StringUtils::replace_no_expand(name, "/", ".");
3346 const char* msg_text1 = "Class loader (instance of): ";
3347 const char* msg_text2 = " tried to load prohibited package name: ";
3348 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3349 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3350 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3351 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3352 }
3353 }
3354 return;
3355 }
3356
3357 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3358 constantPoolHandle i_cp(THREAD, constants());
3359 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3360 int ioff = iter.inner_class_info_index();
3361 if (ioff != 0) {
3362 // Check to see if the name matches the class we're looking for
3363 // before attempting to find the class.
3364 if (i_cp->klass_name_at_matches(this, ioff)) {
3365 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3366 if (this == inner_klass) {
3367 *ooff = iter.outer_class_info_index();
3368 *noff = iter.inner_name_index();
3369 return true;
3370 }
3371 }
3372 }
3373 }
3374 return false;
3375 }
3376
3377 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3378 InstanceKlass* outer_klass = nullptr;
3379 *inner_is_member = false;
3380 int ooff = 0, noff = 0;
3381 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3382 if (has_inner_classes_attr) {
3383 constantPoolHandle i_cp(THREAD, constants());
3384 if (ooff != 0) {
3385 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3386 if (!ok->is_instance_klass()) {
3387 // If the outer class is not an instance klass then it cannot have
3388 // declared any inner classes.
3389 ResourceMark rm(THREAD);
3390 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3391 Exceptions::fthrow(
3392 THREAD_AND_LOCATION,
3393 vmSymbols::java_lang_IncompatibleClassChangeError(),
3394 "%s and %s disagree on InnerClasses attribute",
3395 ok->external_name(),
3396 external_name());
3397 return nullptr;
3398 }
3399 outer_klass = InstanceKlass::cast(ok);
3400 *inner_is_member = true;
3401 }
3402 if (nullptr == outer_klass) {
3403 // It may be a local class; try for that.
3404 int encl_method_class_idx = enclosing_method_class_index();
3405 if (encl_method_class_idx != 0) {
3406 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3407 outer_klass = InstanceKlass::cast(ok);
3408 *inner_is_member = false;
3409 }
3410 }
3411 }
3412
3413 // If no inner class attribute found for this class.
3414 if (nullptr == outer_klass) return nullptr;
3415
3416 // Throws an exception if outer klass has not declared k as an inner klass
3417 // We need evidence that each klass knows about the other, or else
3418 // the system could allow a spoof of an inner class to gain access rights.
3419 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3420 return outer_klass;
3421 }
3422
3423 u2 InstanceKlass::compute_modifier_flags() const {
3424 u2 access = access_flags().as_unsigned_short();
3425
3426 // But check if it happens to be member class.
3427 InnerClassesIterator iter(this);
3428 for (; !iter.done(); iter.next()) {
3429 int ioff = iter.inner_class_info_index();
3430 // Inner class attribute can be zero, skip it.
3431 // Strange but true: JVM spec. allows null inner class refs.
3432 if (ioff == 0) continue;
3433
3434 // only look at classes that are already loaded
3435 // since we are looking for the flags for our self.
3436 Symbol* inner_name = constants()->klass_name_at(ioff);
3437 if (name() == inner_name) {
3438 // This is really a member class.
3439 access = iter.inner_access_flags();
3440 break;
3441 }
3442 }
3443 // Remember to strip ACC_SUPER bit
3444 return (access & (~JVM_ACC_SUPER));
3445 }
3446
3447 jint InstanceKlass::jvmti_class_status() const {
3448 jint result = 0;
3449
3450 if (is_linked()) {
3451 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3452 }
3453
3454 if (is_initialized()) {
3455 assert(is_linked(), "Class status is not consistent");
3456 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3457 }
3458 if (is_in_error_state()) {
3459 result |= JVMTI_CLASS_STATUS_ERROR;
3460 }
3461 return result;
3462 }
3463
3464 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3465 bool implements_interface; // initialized by method_at_itable_or_null
3466 Method* m = method_at_itable_or_null(holder, index,
3467 implements_interface); // out parameter
3468 if (m != nullptr) {
3469 assert(implements_interface, "sanity");
3470 return m;
3471 } else if (implements_interface) {
3472 // Throw AbstractMethodError since corresponding itable slot is empty.
3473 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3474 } else {
3475 // If the interface isn't implemented by the receiver class,
3476 // the VM should throw IncompatibleClassChangeError.
3477 ResourceMark rm(THREAD);
3478 stringStream ss;
3479 bool same_module = (module() == holder->module());
3480 ss.print("Receiver class %s does not implement "
3481 "the interface %s defining the method to be called "
3482 "(%s%s%s)",
3483 external_name(), holder->external_name(),
3484 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3485 (same_module) ? "" : "; ",
3486 (same_module) ? "" : holder->class_in_module_of_loader());
3487 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3488 }
3489 }
3490
3491 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3492 klassItable itable(this);
3493 for (int i = 0; i < itable.size_offset_table(); i++) {
3494 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3495 if (offset_entry->interface_klass() == holder) {
3496 implements_interface = true;
3497 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3498 Method* m = ime[index].method();
3499 return m;
3500 }
3501 }
3502 implements_interface = false;
3503 return nullptr; // offset entry not found
3504 }
3505
3506 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3507 assert(is_linked(), "required");
3508 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3509 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3510
3511 int vtable_index = Method::invalid_vtable_index;
3512 Symbol* name = intf_method->name();
3513 Symbol* signature = intf_method->signature();
3514
3515 // First check in default method array
3516 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3517 int index = find_method_index(default_methods(),
3518 name, signature,
3519 Klass::OverpassLookupMode::find,
3520 Klass::StaticLookupMode::find,
3521 Klass::PrivateLookupMode::find);
3522 if (index >= 0) {
3523 vtable_index = default_vtable_indices()->at(index);
3524 }
3525 }
3526 if (vtable_index == Method::invalid_vtable_index) {
3527 // get vtable_index for miranda methods
3528 klassVtable vt = vtable();
3529 vtable_index = vt.index_of_miranda(name, signature);
3530 }
3531 return vtable_index;
3532 }
3533
3534 #if INCLUDE_JVMTI
3535 // update default_methods for redefineclasses for methods that are
3536 // not yet in the vtable due to concurrent subclass define and superinterface
3537 // redefinition
3538 // Note: those in the vtable, should have been updated via adjust_method_entries
3539 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3540 // search the default_methods for uses of either obsolete or EMCP methods
3541 if (default_methods() != nullptr) {
3542 for (int index = 0; index < default_methods()->length(); index ++) {
3543 Method* old_method = default_methods()->at(index);
3544 if (old_method == nullptr || !old_method->is_old()) {
3545 continue; // skip uninteresting entries
3546 }
3547 assert(!old_method->is_deleted(), "default methods may not be deleted");
3548 Method* new_method = old_method->get_new_method();
3549 default_methods()->at_put(index, new_method);
3550
3551 if (log_is_enabled(Info, redefine, class, update)) {
3552 ResourceMark rm;
3553 if (!(*trace_name_printed)) {
3554 log_info(redefine, class, update)
3555 ("adjust: klassname=%s default methods from name=%s",
3556 external_name(), old_method->method_holder()->external_name());
3557 *trace_name_printed = true;
3558 }
3559 log_debug(redefine, class, update, vtables)
3560 ("default method update: %s(%s) ",
3561 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3562 }
3563 }
3564 }
3565 }
3566 #endif // INCLUDE_JVMTI
3567
3568 // On-stack replacement stuff
3569 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3570 assert_lock_strong(NMethodState_lock);
3571 #ifndef PRODUCT
3572 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3573 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3574 "redundant OSR recompilation detected. memory leak in CodeCache!");
3575 #endif
3576 // only one compilation can be active
3577 assert(n->is_osr_method(), "wrong kind of nmethod");
3578 n->set_osr_link(osr_nmethods_head());
3579 set_osr_nmethods_head(n);
3580 // Raise the highest osr level if necessary
3581 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3582
3583 // Get rid of the osr methods for the same bci that have lower levels.
3584 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3585 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3586 if (inv != nullptr && inv->is_in_use()) {
3587 inv->make_not_entrant();
3588 }
3589 }
3590 }
3591
3592 // Remove osr nmethod from the list. Return true if found and removed.
3593 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3594 // This is a short non-blocking critical region, so the no safepoint check is ok.
3595 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3596 assert(n->is_osr_method(), "wrong kind of nmethod");
3597 nmethod* last = nullptr;
3598 nmethod* cur = osr_nmethods_head();
3599 int max_level = CompLevel_none; // Find the max comp level excluding n
3600 Method* m = n->method();
3601 // Search for match
3602 bool found = false;
3603 while(cur != nullptr && cur != n) {
3604 if (m == cur->method()) {
3605 // Find max level before n
3606 max_level = MAX2(max_level, cur->comp_level());
3607 }
3608 last = cur;
3609 cur = cur->osr_link();
3610 }
3611 nmethod* next = nullptr;
3612 if (cur == n) {
3613 found = true;
3614 next = cur->osr_link();
3615 if (last == nullptr) {
3616 // Remove first element
3617 set_osr_nmethods_head(next);
3618 } else {
3619 last->set_osr_link(next);
3620 }
3621 }
3622 n->set_osr_link(nullptr);
3623 cur = next;
3624 while (cur != nullptr) {
3625 // Find max level after n
3626 if (m == cur->method()) {
3627 max_level = MAX2(max_level, cur->comp_level());
3628 }
3629 cur = cur->osr_link();
3630 }
3631 m->set_highest_osr_comp_level(max_level);
3632 return found;
3633 }
3634
3635 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3636 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3637 nmethod* osr = osr_nmethods_head();
3638 int found = 0;
3639 while (osr != nullptr) {
3640 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3641 if (osr->method() == m) {
3642 deopt_scope->mark(osr);
3643 found++;
3644 }
3645 osr = osr->osr_link();
3646 }
3647 return found;
3648 }
3649
3650 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3651 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3652 nmethod* osr = osr_nmethods_head();
3653 nmethod* best = nullptr;
3654 while (osr != nullptr) {
3655 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3656 // There can be a time when a c1 osr method exists but we are waiting
3657 // for a c2 version. When c2 completes its osr nmethod we will trash
3658 // the c1 version and only be able to find the c2 version. However
3659 // while we overflow in the c1 code at back branches we don't want to
3660 // try and switch to the same code as we are already running
3661
3662 if (osr->method() == m &&
3663 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3664 if (match_level) {
3665 if (osr->comp_level() == comp_level) {
3666 // Found a match - return it.
3667 return osr;
3668 }
3669 } else {
3670 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3671 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3672 // Found the best possible - return it.
3673 return osr;
3674 }
3675 best = osr;
3676 }
3677 }
3678 }
3679 osr = osr->osr_link();
3680 }
3681
3682 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3683 if (best != nullptr && best->comp_level() >= comp_level) {
3684 return best;
3685 }
3686 return nullptr;
3687 }
3688
3689 // -----------------------------------------------------------------------------------------------------
3690 // Printing
3691
3692 #define BULLET " - "
3693
3694 static const char* state_names[] = {
3695 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3696 };
3697
3698 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3699 for (int i = 0; i < len; i++) {
3700 intptr_t e = start[i];
3701 st->print("%d : " INTPTR_FORMAT, i, e);
3702 if (MetaspaceObj::is_valid((Metadata*)e)) {
3703 st->print(" ");
3704 ((Metadata*)e)->print_value_on(st);
3705 }
3706 st->cr();
3707 }
3708 }
3709
3710 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3711 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3712 }
3713
3714 const char* InstanceKlass::init_state_name() const {
3715 return state_names[init_state()];
3716 }
3717
3718 const char* InstanceKlass::state2name(ClassState s) {
3719 return state_names[s];
3720 }
3721
3722 void InstanceKlass::print_on(outputStream* st) const {
3723 assert(is_klass(), "must be klass");
3724 Klass::print_on(st);
3725
3726 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3727 st->print(BULLET"klass size: %d", size()); st->cr();
3728 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3729 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3730 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3731 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3732 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3733 st->print(BULLET"sub: ");
3734 Klass* sub = subklass();
3735 int n;
3736 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3737 if (n < MaxSubklassPrintSize) {
3738 sub->print_value_on(st);
3739 st->print(" ");
3740 }
3741 }
3742 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3743 st->cr();
3744
3745 if (is_interface()) {
3746 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3747 if (nof_implementors() == 1) {
3748 st->print_cr(BULLET"implementor: ");
3749 st->print(" ");
3750 implementor()->print_value_on(st);
3751 st->cr();
3752 }
3753 }
3754
3755 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3756 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3757 if (Verbose || WizardMode) {
3758 Array<Method*>* method_array = methods();
3759 for (int i = 0; i < method_array->length(); i++) {
3760 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3761 }
3762 }
3763 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3764 if (default_methods() != nullptr) {
3765 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3766 if (Verbose) {
3767 Array<Method*>* method_array = default_methods();
3768 for (int i = 0; i < method_array->length(); i++) {
3769 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3770 }
3771 }
3772 }
3773 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3774 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3775 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3776
3777 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3778
3779 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3780 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3781
3782 if (secondary_supers() != nullptr) {
3783 if (Verbose) {
3784 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3785 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3786 for (int i = 0; i < _secondary_supers->length(); i++) {
3787 ResourceMark rm; // for external_name()
3788 Klass* secondary_super = _secondary_supers->at(i);
3789 st->print(BULLET"%2d:", i);
3790 if (is_hashed) {
3791 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3792 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3793 st->print(" dist:%02d:", distance);
3794 }
3795 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3796 }
3797 }
3798 }
3799 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3800
3801 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3802 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3803 if (source_debug_extension() != nullptr) {
3804 st->print(BULLET"source debug extension: ");
3805 st->print("%s", source_debug_extension());
3806 st->cr();
3807 }
3808 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3809 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3810 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3811 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3812 {
3813 bool have_pv = false;
3814 // previous versions are linked together through the InstanceKlass
3815 for (InstanceKlass* pv_node = previous_versions();
3816 pv_node != nullptr;
3817 pv_node = pv_node->previous_versions()) {
3818 if (!have_pv)
3819 st->print(BULLET"previous version: ");
3820 have_pv = true;
3821 pv_node->constants()->print_value_on(st);
3822 }
3823 if (have_pv) st->cr();
3824 }
3825
3826 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3827 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3828 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3829 print_on_maybe_null(st, BULLET"record components: ", record_components());
3830 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3831 if (java_mirror() != nullptr) {
3832 st->print(BULLET"java mirror: ");
3833 java_mirror()->print_value_on(st);
3834 st->cr();
3835 } else {
3836 st->print_cr(BULLET"java mirror: null");
3837 }
3838 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3839 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3840 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3841 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3842 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3843
3844 FieldPrinter print_static_field(st);
3845 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3846 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3847 FieldPrinter print_nonstatic_field(st);
3848 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3849 ik->print_nonstatic_fields(&print_nonstatic_field);
3850
3851 st->print(BULLET"non-static oop maps: ");
3852 OopMapBlock* map = start_of_nonstatic_oop_maps();
3853 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3854 while (map < end_map) {
3855 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3856 map++;
3857 }
3858 st->cr();
3859 }
3860
3861 void InstanceKlass::print_value_on(outputStream* st) const {
3862 assert(is_klass(), "must be klass");
3863 if (Verbose || WizardMode) access_flags().print_on(st);
3864 name()->print_value_on(st);
3865 }
3866
3867 void FieldPrinter::do_field(fieldDescriptor* fd) {
3868 _st->print(BULLET);
3869 if (_obj == nullptr) {
3870 fd->print_on(_st);
3871 _st->cr();
3872 } else {
3873 fd->print_on_for(_st, _obj);
3874 _st->cr();
3875 }
3876 }
3877
3878
3879 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3880 Klass::oop_print_on(obj, st);
3881
3882 if (this == vmClasses::String_klass()) {
3883 typeArrayOop value = java_lang_String::value(obj);
3884 juint length = java_lang_String::length(obj);
3885 if (value != nullptr &&
3886 value->is_typeArray() &&
3887 length <= (juint) value->length()) {
3888 st->print(BULLET"string: ");
3889 java_lang_String::print(obj, st);
3890 st->cr();
3891 }
3892 }
3893
3894 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3895 FieldPrinter print_field(st, obj);
3896 print_nonstatic_fields(&print_field);
3897
3898 if (this == vmClasses::Class_klass()) {
3899 st->print(BULLET"signature: ");
3900 java_lang_Class::print_signature(obj, st);
3901 st->cr();
3902 Klass* real_klass = java_lang_Class::as_Klass(obj);
3903 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3904 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3905 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3906 }
3907 } else if (this == vmClasses::MethodType_klass()) {
3908 st->print(BULLET"signature: ");
3909 java_lang_invoke_MethodType::print_signature(obj, st);
3910 st->cr();
3911 }
3912 }
3913
3914 #ifndef PRODUCT
3915
3916 bool InstanceKlass::verify_itable_index(int i) {
3917 int method_count = klassItable::method_count_for_interface(this);
3918 assert(i >= 0 && i < method_count, "index out of bounds");
3919 return true;
3920 }
3921
3922 #endif //PRODUCT
3923
3924 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3925 st->print("a ");
3926 name()->print_value_on(st);
3927 obj->print_address_on(st);
3928 if (this == vmClasses::String_klass()
3929 && java_lang_String::value(obj) != nullptr) {
3930 ResourceMark rm;
3931 int len = java_lang_String::length(obj);
3932 int plen = (len < 24 ? len : 12);
3933 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3934 st->print(" = \"%s\"", str);
3935 if (len > plen)
3936 st->print("...[%d]", len);
3937 } else if (this == vmClasses::Class_klass()) {
3938 Klass* k = java_lang_Class::as_Klass(obj);
3939 st->print(" = ");
3940 if (k != nullptr) {
3941 k->print_value_on(st);
3942 } else {
3943 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3944 st->print("%s", tname ? tname : "type?");
3945 }
3946 } else if (this == vmClasses::MethodType_klass()) {
3947 st->print(" = ");
3948 java_lang_invoke_MethodType::print_signature(obj, st);
3949 } else if (java_lang_boxing_object::is_instance(obj)) {
3950 st->print(" = ");
3951 java_lang_boxing_object::print(obj, st);
3952 } else if (this == vmClasses::LambdaForm_klass()) {
3953 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3954 if (vmentry != nullptr) {
3955 st->print(" => ");
3956 vmentry->print_value_on(st);
3957 }
3958 } else if (this == vmClasses::MemberName_klass()) {
3959 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3960 if (vmtarget != nullptr) {
3961 st->print(" = ");
3962 vmtarget->print_value_on(st);
3963 } else {
3964 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3965 oop name = java_lang_invoke_MemberName::name(obj);
3966 if (clazz != nullptr) {
3967 clazz->print_value_on(st);
3968 } else {
3969 st->print("null");
3970 }
3971 st->print(".");
3972 if (name != nullptr) {
3973 name->print_value_on(st);
3974 } else {
3975 st->print("null");
3976 }
3977 }
3978 }
3979 }
3980
3981 const char* InstanceKlass::internal_name() const {
3982 return external_name();
3983 }
3984
3985 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3986 const ModuleEntry* module_entry,
3987 const ClassFileStream* cfs) const {
3988
3989 if (ClassListWriter::is_enabled()) {
3990 ClassListWriter::write(this, cfs);
3991 }
3992
3993 print_class_load_helper(loader_data, module_entry, cfs);
3994 print_class_load_cause_logging();
3995 }
3996
3997 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3998 const ModuleEntry* module_entry,
3999 const ClassFileStream* cfs) const {
4000
4001 if (!log_is_enabled(Info, class, load)) {
4002 return;
4003 }
4004
4005 ResourceMark rm;
4006 LogMessage(class, load) msg;
4007 stringStream info_stream;
4008
4009 // Name and class hierarchy info
4010 info_stream.print("%s", external_name());
4011
4012 // Source
4013 if (cfs != nullptr) {
4014 if (cfs->source() != nullptr) {
4015 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4016 if (module_name != nullptr) {
4017 // When the boot loader created the stream, it didn't know the module name
4018 // yet. Let's format it now.
4019 if (cfs->from_boot_loader_modules_image()) {
4020 info_stream.print(" source: jrt:/%s", module_name);
4021 } else {
4022 info_stream.print(" source: %s", cfs->source());
4023 }
4024 } else {
4025 info_stream.print(" source: %s", cfs->source());
4026 }
4027 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4028 Thread* current = Thread::current();
4029 Klass* caller = current->is_Java_thread() ?
4030 JavaThread::cast(current)->security_get_caller_class(1):
4031 nullptr;
4032 // caller can be null, for example, during a JVMTI VM_Init hook
4033 if (caller != nullptr) {
4034 info_stream.print(" source: instance of %s", caller->external_name());
4035 } else {
4036 // source is unknown
4037 }
4038 } else {
4039 oop class_loader = loader_data->class_loader();
4040 info_stream.print(" source: %s", class_loader->klass()->external_name());
4041 }
4042 } else {
4043 assert(this->is_shared(), "must be");
4044 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4045 info_stream.print(" source: shared objects file (top)");
4046 } else {
4047 info_stream.print(" source: shared objects file");
4048 }
4049 }
4050
4051 info_stream.print(" loader:");
4052 if (is_shared()) {
4053 info_stream.print(" %s", SystemDictionaryShared::class_loader_name_for_shared((Klass*)this));
4054 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4055 info_stream.print(" boot_loader");
4056 } else {
4057 oop class_loader = loader_data->class_loader();
4058 if (class_loader != nullptr) {
4059 info_stream.print(" %s", class_loader->klass()->external_name());
4060 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4061 if (cl_name_and_id != nullptr) {
4062 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4063 }
4064 } else {
4065 info_stream.print(" null");
4066 }
4067 }
4068 msg.info("%s", info_stream.as_string());
4069
4070 if (log_is_enabled(Debug, class, load)) {
4071 stringStream debug_stream;
4072
4073 // Class hierarchy info
4074 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4075 p2i(this), p2i(superklass()));
4076
4077 // Interfaces
4078 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4079 debug_stream.print(" interfaces:");
4080 int length = local_interfaces()->length();
4081 for (int i = 0; i < length; i++) {
4082 debug_stream.print(" " PTR_FORMAT,
4083 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4084 }
4085 }
4086
4087 // Class loader
4088 debug_stream.print(" loader: [");
4089 loader_data->print_value_on(&debug_stream);
4090 debug_stream.print("]");
4091
4092 // Classfile checksum
4093 if (cfs) {
4094 debug_stream.print(" bytes: %d checksum: %08x",
4095 cfs->length(),
4096 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4097 cfs->length()));
4098 }
4099
4100 msg.debug("%s", debug_stream.as_string());
4101 }
4102 }
4103
4104 void InstanceKlass::print_class_load_cause_logging() const {
4105 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4106 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4107 JavaThread* current = JavaThread::current();
4108 ResourceMark rm(current);
4109 const char* name = external_name();
4110
4111 if (LogClassLoadingCauseFor == nullptr ||
4112 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4113 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4114 return;
4115 }
4116
4117 // Log Java stack first
4118 {
4119 LogMessage(class, load, cause) msg;
4120 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4121
4122 info_stream.print_cr("Java stack when loading %s:", name);
4123 current->print_stack_on(&info_stream);
4124 }
4125
4126 // Log native stack second
4127 if (log_cause_native) {
4128 // Log to string first so that lines can be indented
4129 stringStream stack_stream;
4130 char buf[O_BUFLEN];
4131 address lastpc = nullptr;
4132 NativeStackPrinter nsp(current);
4133 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4134 true /* print_source_info */, -1 /* max stack */);
4135
4136 LogMessage(class, load, cause, native) msg;
4137 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4138 info_stream.print_cr("Native stack when loading %s:", name);
4139
4140 // Print each native stack line to the log
4141 int size = (int) stack_stream.size();
4142 char* stack = stack_stream.as_string();
4143 char* stack_end = stack + size;
4144 char* line_start = stack;
4145 for (char* p = stack; p < stack_end; p++) {
4146 if (*p == '\n') {
4147 *p = '\0';
4148 info_stream.print_cr("\t%s", line_start);
4149 line_start = p + 1;
4150 }
4151 }
4152 if (line_start < stack_end) {
4153 info_stream.print_cr("\t%s", line_start);
4154 }
4155 }
4156 }
4157 }
4158
4159 // Verification
4160
4161 class VerifyFieldClosure: public BasicOopIterateClosure {
4162 protected:
4163 template <class T> void do_oop_work(T* p) {
4164 oop obj = RawAccess<>::oop_load(p);
4165 if (!oopDesc::is_oop_or_null(obj)) {
4166 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4167 Universe::print_on(tty);
4168 guarantee(false, "boom");
4169 }
4170 }
4171 public:
4172 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4173 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4174 };
4175
4176 void InstanceKlass::verify_on(outputStream* st) {
4177 #ifndef PRODUCT
4178 // Avoid redundant verifies, this really should be in product.
4179 if (_verify_count == Universe::verify_count()) return;
4180 _verify_count = Universe::verify_count();
4181 #endif
4182
4183 // Verify Klass
4184 Klass::verify_on(st);
4185
4186 // Verify that klass is present in ClassLoaderData
4187 guarantee(class_loader_data()->contains_klass(this),
4188 "this class isn't found in class loader data");
4189
4190 // Verify vtables
4191 if (is_linked()) {
4192 // $$$ This used to be done only for m/s collections. Doing it
4193 // always seemed a valid generalization. (DLD -- 6/00)
4194 vtable().verify(st);
4195 }
4196
4197 // Verify first subklass
4198 if (subklass() != nullptr) {
4199 guarantee(subklass()->is_klass(), "should be klass");
4200 }
4201
4202 // Verify siblings
4203 Klass* super = this->super();
4204 Klass* sib = next_sibling();
4205 if (sib != nullptr) {
4206 if (sib == this) {
4207 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4208 }
4209
4210 guarantee(sib->is_klass(), "should be klass");
4211 guarantee(sib->super() == super, "siblings should have same superklass");
4212 }
4213
4214 // Verify local interfaces
4215 if (local_interfaces()) {
4216 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4217 for (int j = 0; j < local_interfaces->length(); j++) {
4218 InstanceKlass* e = local_interfaces->at(j);
4219 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4220 }
4221 }
4222
4223 // Verify transitive interfaces
4224 if (transitive_interfaces() != nullptr) {
4225 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4226 for (int j = 0; j < transitive_interfaces->length(); j++) {
4227 InstanceKlass* e = transitive_interfaces->at(j);
4228 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4229 }
4230 }
4231
4232 // Verify methods
4233 if (methods() != nullptr) {
4234 Array<Method*>* methods = this->methods();
4235 for (int j = 0; j < methods->length(); j++) {
4236 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4237 }
4238 for (int j = 0; j < methods->length() - 1; j++) {
4239 Method* m1 = methods->at(j);
4240 Method* m2 = methods->at(j + 1);
4241 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4242 }
4243 }
4244
4245 // Verify method ordering
4246 if (method_ordering() != nullptr) {
4247 Array<int>* method_ordering = this->method_ordering();
4248 int length = method_ordering->length();
4249 if (JvmtiExport::can_maintain_original_method_order() ||
4250 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4251 guarantee(length == methods()->length(), "invalid method ordering length");
4252 jlong sum = 0;
4253 for (int j = 0; j < length; j++) {
4254 int original_index = method_ordering->at(j);
4255 guarantee(original_index >= 0, "invalid method ordering index");
4256 guarantee(original_index < length, "invalid method ordering index");
4257 sum += original_index;
4258 }
4259 // Verify sum of indices 0,1,...,length-1
4260 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4261 } else {
4262 guarantee(length == 0, "invalid method ordering length");
4263 }
4264 }
4265
4266 // Verify default methods
4267 if (default_methods() != nullptr) {
4268 Array<Method*>* methods = this->default_methods();
4269 for (int j = 0; j < methods->length(); j++) {
4270 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4271 }
4272 for (int j = 0; j < methods->length() - 1; j++) {
4273 Method* m1 = methods->at(j);
4274 Method* m2 = methods->at(j + 1);
4275 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4276 }
4277 }
4278
4279 // Verify JNI static field identifiers
4280 if (jni_ids() != nullptr) {
4281 jni_ids()->verify(this);
4282 }
4283
4284 // Verify other fields
4285 if (constants() != nullptr) {
4286 guarantee(constants()->is_constantPool(), "should be constant pool");
4287 }
4288 }
4289
4290 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4291 Klass::oop_verify_on(obj, st);
4292 VerifyFieldClosure blk;
4293 obj->oop_iterate(&blk);
4294 }
4295
4296
4297 // JNIid class for jfieldIDs only
4298 // Note to reviewers:
4299 // These JNI functions are just moved over to column 1 and not changed
4300 // in the compressed oops workspace.
4301 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4302 _holder = holder;
4303 _offset = offset;
4304 _next = next;
4305 debug_only(_is_static_field_id = false;)
4306 }
4307
4308
4309 JNIid* JNIid::find(int offset) {
4310 JNIid* current = this;
4311 while (current != nullptr) {
4312 if (current->offset() == offset) return current;
4313 current = current->next();
4314 }
4315 return nullptr;
4316 }
4317
4318 void JNIid::deallocate(JNIid* current) {
4319 while (current != nullptr) {
4320 JNIid* next = current->next();
4321 delete current;
4322 current = next;
4323 }
4324 }
4325
4326
4327 void JNIid::verify(Klass* holder) {
4328 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4329 int end_field_offset;
4330 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4331
4332 JNIid* current = this;
4333 while (current != nullptr) {
4334 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4335 #ifdef ASSERT
4336 int o = current->offset();
4337 if (current->is_static_field_id()) {
4338 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4339 }
4340 #endif
4341 current = current->next();
4342 }
4343 }
4344
4345 void InstanceKlass::set_init_state(ClassState state) {
4346 #ifdef ASSERT
4347 bool good_state = is_shared() ? (_init_state <= state)
4348 : (_init_state < state);
4349 assert(good_state || state == allocated, "illegal state transition");
4350 #endif
4351 assert(_init_thread == nullptr, "should be cleared before state change");
4352 Atomic::release_store(&_init_state, state);
4353 }
4354
4355 #if INCLUDE_JVMTI
4356
4357 // RedefineClasses() support for previous versions
4358
4359 // Globally, there is at least one previous version of a class to walk
4360 // during class unloading, which is saved because old methods in the class
4361 // are still running. Otherwise the previous version list is cleaned up.
4362 bool InstanceKlass::_should_clean_previous_versions = false;
4363
4364 // Returns true if there are previous versions of a class for class
4365 // unloading only. Also resets the flag to false. purge_previous_version
4366 // will set the flag to true if there are any left, i.e., if there's any
4367 // work to do for next time. This is to avoid the expensive code cache
4368 // walk in CLDG::clean_deallocate_lists().
4369 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4370 bool ret = _should_clean_previous_versions;
4371 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4372 ret ? "true" : "false");
4373 _should_clean_previous_versions = false;
4374 return ret;
4375 }
4376
4377 // This nulls out jmethodIDs for all methods in 'klass'
4378 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4379 // during class unloading.
4380 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4381 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4382 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4383 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4384 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4385 Array<Method*>* method_refs = klass->methods();
4386 for (int k = 0; k < method_refs->length(); k++) {
4387 Method* method = method_refs->at(k);
4388 if (method != nullptr && method->is_obsolete()) {
4389 method->clear_jmethod_id();
4390 }
4391 }
4392 }
4393
4394 // Purge previous versions before adding new previous versions of the class and
4395 // during class unloading.
4396 void InstanceKlass::purge_previous_version_list() {
4397 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4398 assert(has_been_redefined(), "Should only be called for main class");
4399
4400 // Quick exit.
4401 if (previous_versions() == nullptr) {
4402 return;
4403 }
4404
4405 // This klass has previous versions so see what we can cleanup
4406 // while it is safe to do so.
4407
4408 int deleted_count = 0; // leave debugging breadcrumbs
4409 int live_count = 0;
4410 ClassLoaderData* loader_data = class_loader_data();
4411 assert(loader_data != nullptr, "should never be null");
4412
4413 ResourceMark rm;
4414 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4415
4416 // previous versions are linked together through the InstanceKlass
4417 InstanceKlass* pv_node = previous_versions();
4418 InstanceKlass* last = this;
4419 int version = 0;
4420
4421 // check the previous versions list
4422 for (; pv_node != nullptr; ) {
4423
4424 ConstantPool* pvcp = pv_node->constants();
4425 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4426
4427 if (!pvcp->on_stack()) {
4428 // If the constant pool isn't on stack, none of the methods
4429 // are executing. Unlink this previous_version.
4430 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4431 // so will be deallocated during the next phase of class unloading.
4432 log_trace(redefine, class, iklass, purge)
4433 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4434 // Unlink from previous version list.
4435 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4436 InstanceKlass* next = pv_node->previous_versions();
4437 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4438 pv_node->link_previous_versions(nullptr); // point next to null
4439 last->link_previous_versions(next);
4440 // Delete this node directly. Nothing is referring to it and we don't
4441 // want it to increase the counter for metadata to delete in CLDG.
4442 MetadataFactory::free_metadata(loader_data, pv_node);
4443 pv_node = next;
4444 deleted_count++;
4445 version++;
4446 continue;
4447 } else {
4448 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4449 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4450 live_count++;
4451 if (pvcp->is_shared()) {
4452 // Shared previous versions can never be removed so no cleaning is needed.
4453 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4454 } else {
4455 // Previous version alive, set that clean is needed for next time.
4456 _should_clean_previous_versions = true;
4457 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4458 }
4459 }
4460
4461 // next previous version
4462 last = pv_node;
4463 pv_node = pv_node->previous_versions();
4464 version++;
4465 }
4466 log_trace(redefine, class, iklass, purge)
4467 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4468 }
4469
4470 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4471 int emcp_method_count) {
4472 int obsolete_method_count = old_methods->length() - emcp_method_count;
4473
4474 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4475 _previous_versions != nullptr) {
4476 // We have a mix of obsolete and EMCP methods so we have to
4477 // clear out any matching EMCP method entries the hard way.
4478 int local_count = 0;
4479 for (int i = 0; i < old_methods->length(); i++) {
4480 Method* old_method = old_methods->at(i);
4481 if (old_method->is_obsolete()) {
4482 // only obsolete methods are interesting
4483 Symbol* m_name = old_method->name();
4484 Symbol* m_signature = old_method->signature();
4485
4486 // previous versions are linked together through the InstanceKlass
4487 int j = 0;
4488 for (InstanceKlass* prev_version = _previous_versions;
4489 prev_version != nullptr;
4490 prev_version = prev_version->previous_versions(), j++) {
4491
4492 Array<Method*>* method_refs = prev_version->methods();
4493 for (int k = 0; k < method_refs->length(); k++) {
4494 Method* method = method_refs->at(k);
4495
4496 if (!method->is_obsolete() &&
4497 method->name() == m_name &&
4498 method->signature() == m_signature) {
4499 // The current RedefineClasses() call has made all EMCP
4500 // versions of this method obsolete so mark it as obsolete
4501 log_trace(redefine, class, iklass, add)
4502 ("%s(%s): flush obsolete method @%d in version @%d",
4503 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4504
4505 method->set_is_obsolete();
4506 break;
4507 }
4508 }
4509
4510 // The previous loop may not find a matching EMCP method, but
4511 // that doesn't mean that we can optimize and not go any
4512 // further back in the PreviousVersion generations. The EMCP
4513 // method for this generation could have already been made obsolete,
4514 // but there still may be an older EMCP method that has not
4515 // been made obsolete.
4516 }
4517
4518 if (++local_count >= obsolete_method_count) {
4519 // no more obsolete methods so bail out now
4520 break;
4521 }
4522 }
4523 }
4524 }
4525 }
4526
4527 // Save the scratch_class as the previous version if any of the methods are running.
4528 // The previous_versions are used to set breakpoints in EMCP methods and they are
4529 // also used to clean MethodData links to redefined methods that are no longer running.
4530 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4531 int emcp_method_count) {
4532 assert(Thread::current()->is_VM_thread(),
4533 "only VMThread can add previous versions");
4534
4535 ResourceMark rm;
4536 log_trace(redefine, class, iklass, add)
4537 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4538
4539 // Clean out old previous versions for this class
4540 purge_previous_version_list();
4541
4542 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4543 // a previous redefinition may be made obsolete by this redefinition.
4544 Array<Method*>* old_methods = scratch_class->methods();
4545 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4546
4547 // If the constant pool for this previous version of the class
4548 // is not marked as being on the stack, then none of the methods
4549 // in this previous version of the class are on the stack so
4550 // we don't need to add this as a previous version.
4551 ConstantPool* cp_ref = scratch_class->constants();
4552 if (!cp_ref->on_stack()) {
4553 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4554 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4555 return;
4556 }
4557
4558 // Add previous version if any methods are still running or if this is
4559 // a shared class which should never be removed.
4560 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4561 scratch_class->link_previous_versions(previous_versions());
4562 link_previous_versions(scratch_class);
4563 if (cp_ref->is_shared()) {
4564 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4565 } else {
4566 // We only set clean_previous_versions flag for processing during class
4567 // unloading for non-shared classes.
4568 _should_clean_previous_versions = true;
4569 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4570 }
4571 } // end add_previous_version()
4572
4573 #endif // INCLUDE_JVMTI
4574
4575 Method* InstanceKlass::method_with_idnum(int idnum) {
4576 Method* m = nullptr;
4577 if (idnum < methods()->length()) {
4578 m = methods()->at(idnum);
4579 }
4580 if (m == nullptr || m->method_idnum() != idnum) {
4581 for (int index = 0; index < methods()->length(); ++index) {
4582 m = methods()->at(index);
4583 if (m->method_idnum() == idnum) {
4584 return m;
4585 }
4586 }
4587 // None found, return null for the caller to handle.
4588 return nullptr;
4589 }
4590 return m;
4591 }
4592
4593
4594 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4595 if (idnum >= methods()->length()) {
4596 return nullptr;
4597 }
4598 Method* m = methods()->at(idnum);
4599 if (m != nullptr && m->orig_method_idnum() == idnum) {
4600 return m;
4601 }
4602 // Obsolete method idnum does not match the original idnum
4603 for (int index = 0; index < methods()->length(); ++index) {
4604 m = methods()->at(index);
4605 if (m->orig_method_idnum() == idnum) {
4606 return m;
4607 }
4608 }
4609 // None found, return null for the caller to handle.
4610 return nullptr;
4611 }
4612
4613
4614 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4615 InstanceKlass* holder = get_klass_version(version);
4616 if (holder == nullptr) {
4617 return nullptr; // The version of klass is gone, no method is found
4618 }
4619 Method* method = holder->method_with_orig_idnum(idnum);
4620 return method;
4621 }
4622
4623 #if INCLUDE_JVMTI
4624 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4625 return _cached_class_file;
4626 }
4627
4628 jint InstanceKlass::get_cached_class_file_len() {
4629 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4630 }
4631
4632 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4633 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4634 }
4635 #endif
4636
4637 // Make a step iterating over the class hierarchy under the root class.
4638 // Skips subclasses if requested.
4639 void ClassHierarchyIterator::next() {
4640 assert(_current != nullptr, "required");
4641 if (_visit_subclasses && _current->subklass() != nullptr) {
4642 _current = _current->subklass();
4643 return; // visit next subclass
4644 }
4645 _visit_subclasses = true; // reset
4646 while (_current->next_sibling() == nullptr && _current != _root) {
4647 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4648 }
4649 if (_current == _root) {
4650 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4651 _current = nullptr;
4652 return;
4653 }
4654 _current = _current->next_sibling();
4655 return; // visit next sibling subclass
4656 }