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