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/markWord.hpp"
73 #include "oops/method.hpp"
74 #include "oops/oop.inline.hpp"
75 #include "oops/recordComponent.hpp"
76 #include "oops/symbol.hpp"
77 #include "oops/inlineKlass.hpp"
78 #include "prims/jvmtiExport.hpp"
79 #include "prims/jvmtiRedefineClasses.hpp"
80 #include "prims/jvmtiThreadState.hpp"
81 #include "prims/methodComparator.hpp"
82 #include "runtime/arguments.hpp"
83 #include "runtime/deoptimization.hpp"
84 #include "runtime/atomic.hpp"
85 #include "runtime/fieldDescriptor.inline.hpp"
86 #include "runtime/handles.inline.hpp"
87 #include "runtime/javaCalls.hpp"
88 #include "runtime/javaThread.inline.hpp"
89 #include "runtime/mutexLocker.hpp"
90 #include "runtime/orderAccess.hpp"
91 #include "runtime/os.inline.hpp"
92 #include "runtime/reflection.hpp"
93 #include "runtime/synchronizer.hpp"
94 #include "runtime/threads.hpp"
95 #include "services/classLoadingService.hpp"
96 #include "services/finalizerService.hpp"
97 #include "services/threadService.hpp"
98 #include "utilities/dtrace.hpp"
99 #include "utilities/events.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/nativeStackPrinter.hpp"
102 #include "utilities/pair.hpp"
103 #include "utilities/stringUtils.hpp"
104 #ifdef COMPILER1
105 #include "c1/c1_Compiler.hpp"
106 #endif
107 #if INCLUDE_JFR
108 #include "jfr/jfrEvents.hpp"
109 #endif
110
111 #ifdef DTRACE_ENABLED
112
113
114 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
115 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
116 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
117 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
118 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
119 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
120 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
121 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
122 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
123 { \
124 char* data = nullptr; \
125 int len = 0; \
126 Symbol* clss_name = name(); \
127 if (clss_name != nullptr) { \
128 data = (char*)clss_name->bytes(); \
129 len = clss_name->utf8_length(); \
130 } \
131 HOTSPOT_CLASS_INITIALIZATION_##type( \
132 data, len, (void*)class_loader(), thread_type); \
133 }
134
135 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
136 { \
137 char* data = nullptr; \
138 int len = 0; \
139 Symbol* clss_name = name(); \
140 if (clss_name != nullptr) { \
141 data = (char*)clss_name->bytes(); \
142 len = clss_name->utf8_length(); \
143 } \
144 HOTSPOT_CLASS_INITIALIZATION_##type( \
145 data, len, (void*)class_loader(), thread_type, wait); \
146 }
147
148 #else // ndef DTRACE_ENABLED
149
150 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
151 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
152
153 #endif // ndef DTRACE_ENABLED
154
155 void InlineLayoutInfo::metaspace_pointers_do(MetaspaceClosure* it) {
156 log_trace(cds)("Iter(InlineFieldInfo): %p", this);
157 it->push(&_klass);
158 }
159
160 bool InstanceKlass::_finalization_enabled = true;
161
162 static inline bool is_class_loader(const Symbol* class_name,
163 const ClassFileParser& parser) {
164 assert(class_name != nullptr, "invariant");
165
166 if (class_name == vmSymbols::java_lang_ClassLoader()) {
167 return true;
168 }
169
170 if (vmClasses::ClassLoader_klass_loaded()) {
171 const Klass* const super_klass = parser.super_klass();
172 if (super_klass != nullptr) {
173 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
174 return true;
175 }
176 }
177 }
178 return false;
179 }
180
181 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
182 return field(index).field_flags().is_null_free_inline_type();
183 }
184
185 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
186 if (_loadable_descriptors == nullptr) return false;
187 for (int i = 0; i < _loadable_descriptors->length(); i++) {
188 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
189 if (class_name == name) return true;
190 }
191 return false;
192 }
193
194 static inline bool is_stack_chunk_class(const Symbol* class_name,
195 const ClassLoaderData* loader_data) {
196 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
197 loader_data->is_the_null_class_loader_data());
198 }
199
200 // private: called to verify that k is a static member of this nest.
201 // We know that k is an instance class in the same package and hence the
202 // same classloader.
203 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
204 assert(!is_hidden(), "unexpected hidden class");
205 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
206 if (log_is_enabled(Trace, class, nestmates)) {
207 ResourceMark rm(current);
208 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
209 k->external_name(), this->external_name());
210 }
211 return false;
212 }
213
214 if (log_is_enabled(Trace, class, nestmates)) {
215 ResourceMark rm(current);
216 log_trace(class, nestmates)("Checking nest membership of %s in %s",
217 k->external_name(), this->external_name());
218 }
219
220 // Check for the named class in _nest_members.
221 // We don't resolve, or load, any classes.
222 for (int i = 0; i < _nest_members->length(); i++) {
223 int cp_index = _nest_members->at(i);
224 Symbol* name = _constants->klass_name_at(cp_index);
225 if (name == k->name()) {
226 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
227 return true;
228 }
229 }
230 log_trace(class, nestmates)("- class is NOT a nest member!");
231 return false;
232 }
233
234 // Called to verify that k is a permitted subclass of this class.
235 // The incoming stringStream is used to format the messages for error logging and for the caller
236 // to use for exception throwing.
237 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
238 Thread* current = Thread::current();
239 assert(k != nullptr, "sanity check");
240 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
241 "unexpected empty _permitted_subclasses array");
242
243 if (log_is_enabled(Trace, class, sealed)) {
244 ResourceMark rm(current);
245 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
246 k->external_name(), this->external_name());
247 }
248
249 // Check that the class and its super are in the same module.
250 if (k->module() != this->module()) {
251 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
252 "and sealed class %s is in module '%s' with loader %s",
253 k->external_name(),
254 k->module()->name_as_C_string(),
255 k->module()->loader_data()->loader_name_and_id(),
256 this->external_name(),
257 this->module()->name_as_C_string(),
258 this->module()->loader_data()->loader_name_and_id());
259 log_trace(class, sealed)(" - %s", ss.as_string());
260 return false;
261 }
262
263 if (!k->is_public() && !is_same_class_package(k)) {
264 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
265 "and sealed class %s is in package '%s' with classloader %s",
266 k->external_name(),
267 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
268 k->module()->loader_data()->loader_name_and_id(),
269 this->external_name(),
270 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
271 this->module()->loader_data()->loader_name_and_id());
272 log_trace(class, sealed)(" - %s", ss.as_string());
273 return false;
274 }
275
276 for (int i = 0; i < _permitted_subclasses->length(); i++) {
277 int cp_index = _permitted_subclasses->at(i);
278 Symbol* name = _constants->klass_name_at(cp_index);
279 if (name == k->name()) {
280 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
281 return true;
282 }
283 }
284
285 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
286 k->external_name(), this->external_name());
287 log_trace(class, sealed)(" - %s", ss.as_string());
288 return false;
289 }
290
291 // Return nest-host class, resolving, validating and saving it if needed.
292 // In cases where this is called from a thread that cannot do classloading
293 // (such as a native JIT thread) then we simply return null, which in turn
294 // causes the access check to return false. Such code will retry the access
295 // from a more suitable environment later. Otherwise the _nest_host is always
296 // set once this method returns.
297 // Any errors from nest-host resolution must be preserved so they can be queried
298 // from higher-level access checking code, and reported as part of access checking
299 // exceptions.
300 // VirtualMachineErrors are propagated with a null return.
301 // Under any conditions where the _nest_host can be set to non-null the resulting
302 // value of it and, if applicable, the nest host resolution/validation error,
303 // are idempotent.
304 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
305 InstanceKlass* nest_host_k = _nest_host;
306 if (nest_host_k != nullptr) {
307 return nest_host_k;
308 }
309
310 ResourceMark rm(THREAD);
311
312 // need to resolve and save our nest-host class.
313 if (_nest_host_index != 0) { // we have a real nest_host
314 // Before trying to resolve check if we're in a suitable context
315 bool can_resolve = THREAD->can_call_java();
316 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
317 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
318 this->external_name());
319 return nullptr; // sentinel to say "try again from a different context"
320 }
321
322 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
323 this->external_name(),
324 _constants->klass_name_at(_nest_host_index)->as_C_string());
325
326 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
327 if (HAS_PENDING_EXCEPTION) {
328 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
329 return nullptr; // propagate VMEs
330 }
331 stringStream ss;
332 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
333 ss.print("Nest host resolution of %s with host %s failed: ",
334 this->external_name(), target_host_class);
335 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
336 const char* msg = ss.as_string(true /* on C-heap */);
337 constantPoolHandle cph(THREAD, constants());
338 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
339 CLEAR_PENDING_EXCEPTION;
340
341 log_trace(class, nestmates)("%s", msg);
342 } else {
343 // A valid nest-host is an instance class in the current package that lists this
344 // class as a nest member. If any of these conditions are not met the class is
345 // its own nest-host.
346 const char* error = nullptr;
347
348 // JVMS 5.4.4 indicates package check comes first
349 if (is_same_class_package(k)) {
350 // Now check actual membership. We can't be a member if our "host" is
351 // not an instance class.
352 if (k->is_instance_klass()) {
353 nest_host_k = InstanceKlass::cast(k);
354 bool is_member = nest_host_k->has_nest_member(THREAD, this);
355 if (is_member) {
356 _nest_host = nest_host_k; // save resolved nest-host value
357
358 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
359 this->external_name(), k->external_name());
360 return nest_host_k;
361 } else {
362 error = "current type is not listed as a nest member";
363 }
364 } else {
365 error = "host is not an instance class";
366 }
367 } else {
368 error = "types are in different packages";
369 }
370
371 // something went wrong, so record what and log it
372 {
373 stringStream ss;
374 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
375 this->external_name(),
376 this->class_loader_data()->loader_name_and_id(),
377 k->external_name(),
378 k->class_loader_data()->loader_name_and_id(),
379 error);
380 const char* msg = ss.as_string(true /* on C-heap */);
381 constantPoolHandle cph(THREAD, constants());
382 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
383 log_trace(class, nestmates)("%s", msg);
384 }
385 }
386 } else {
387 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
388 this->external_name());
389 }
390
391 // Either not in an explicit nest, or else an error occurred, so
392 // the nest-host is set to `this`. Any thread that sees this assignment
393 // will also see any setting of nest_host_error(), if applicable.
394 return (_nest_host = this);
395 }
396
397 // Dynamic nest member support: set this class's nest host to the given class.
398 // This occurs as part of the class definition, as soon as the instanceKlass
399 // has been created and doesn't require further resolution. The code:
400 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
401 // results in:
402 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
403 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
404 // We also know the "host" is a valid nest-host in the same package so we can
405 // assert some of those facts.
406 void InstanceKlass::set_nest_host(InstanceKlass* host) {
407 assert(is_hidden(), "must be a hidden class");
408 assert(host != nullptr, "null nest host specified");
409 assert(_nest_host == nullptr, "current class has resolved nest-host");
410 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
411 nest_host_error());
412 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
413 (host->_nest_host == host), "proposed host is not a valid nest-host");
414 // Can't assert this as package is not set yet:
415 // assert(is_same_class_package(host), "proposed host is in wrong package");
416
417 if (log_is_enabled(Trace, class, nestmates)) {
418 ResourceMark rm;
419 const char* msg = "";
420 // a hidden class does not expect a statically defined nest-host
421 if (_nest_host_index > 0) {
422 msg = "(the NestHost attribute in the current class is ignored)";
423 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
424 msg = "(the NestMembers attribute in the current class is ignored)";
425 }
426 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
427 this->external_name(),
428 host->external_name(),
429 msg);
430 }
431 // set dynamic nest host
432 _nest_host = host;
433 // Record dependency to keep nest host from being unloaded before this class.
434 ClassLoaderData* this_key = class_loader_data();
435 assert(this_key != nullptr, "sanity");
436 this_key->record_dependency(host);
437 }
438
439 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
440 // or we are k's nest_host - all of which is covered by comparing the two
441 // resolved_nest_hosts.
442 // Any exceptions (i.e. VMEs) are propagated.
443 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
444
445 assert(this != k, "this should be handled by higher-level code");
446
447 // Per JVMS 5.4.4 we first resolve and validate the current class, then
448 // the target class k.
449
450 InstanceKlass* cur_host = nest_host(CHECK_false);
451 if (cur_host == nullptr) {
452 return false;
453 }
454
455 Klass* k_nest_host = k->nest_host(CHECK_false);
456 if (k_nest_host == nullptr) {
457 return false;
458 }
459
460 bool access = (cur_host == k_nest_host);
461
462 ResourceMark rm(THREAD);
463 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
464 this->external_name(),
465 access ? "" : "NOT ",
466 k->external_name());
467 return access;
468 }
469
470 const char* InstanceKlass::nest_host_error() {
471 if (_nest_host_index == 0) {
472 return nullptr;
473 } else {
474 constantPoolHandle cph(Thread::current(), constants());
475 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
476 }
477 }
478
479 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
480 bool use_class_space, TRAPS) throw() {
481 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
482 }
483
484 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
485 const int size = InstanceKlass::size(parser.vtable_size(),
486 parser.itable_size(),
487 nonstatic_oop_map_size(parser.total_oop_map_count()),
488 parser.is_interface(),
489 parser.is_inline_type());
490
491 const Symbol* const class_name = parser.class_name();
492 assert(class_name != nullptr, "invariant");
493 ClassLoaderData* loader_data = parser.loader_data();
494 assert(loader_data != nullptr, "invariant");
495
496 InstanceKlass* ik;
497 const bool use_class_space = parser.klass_needs_narrow_id();
498
499 // Allocation
500 if (parser.is_instance_ref_klass()) {
501 // java.lang.ref.Reference
502 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
503 } else if (class_name == vmSymbols::java_lang_Class()) {
504 // mirror - java.lang.Class
505 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
506 } else if (is_stack_chunk_class(class_name, loader_data)) {
507 // stack chunk
508 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
509 } else if (is_class_loader(class_name, parser)) {
510 // class loader - java.lang.ClassLoader
511 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
512 } else if (parser.is_inline_type()) {
513 // inline type
514 ik = new (loader_data, size, use_class_space, THREAD) InlineKlass(parser);
515 } else {
516 // normal
517 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
518 }
519
520 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
521 assert(CompressedKlassPointers::is_encodable(ik),
522 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
523 }
524
525 // Check for pending exception before adding to the loader data and incrementing
526 // class count. Can get OOM here.
527 if (HAS_PENDING_EXCEPTION) {
528 return nullptr;
529 }
530
531 #ifdef ASSERT
532 ik->bounds_check((address) ik->start_of_vtable(), false, size);
533 ik->bounds_check((address) ik->start_of_itable(), false, size);
534 ik->bounds_check((address) ik->end_of_itable(), true, size);
535 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
536 #endif //ASSERT
537 return ik;
538 }
539
540 #ifndef PRODUCT
541 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
542 const char* bad = nullptr;
543 address end = nullptr;
544 if (addr < (address)this) {
545 bad = "before";
546 } else if (addr == (address)this) {
547 if (edge_ok) return true;
548 bad = "just before";
549 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
550 if (edge_ok) return true;
551 bad = "just after";
552 } else if (addr > end) {
553 bad = "after";
554 } else {
555 return true;
556 }
557 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
558 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
559 Verbose = WizardMode = true; this->print(); //@@
560 return false;
561 }
562 #endif //PRODUCT
563
564 // copy method ordering from resource area to Metaspace
565 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
566 if (m != nullptr) {
567 // allocate a new array and copy contents (memcpy?)
568 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
569 for (int i = 0; i < m->length(); i++) {
570 _method_ordering->at_put(i, m->at(i));
571 }
572 } else {
573 _method_ordering = Universe::the_empty_int_array();
574 }
575 }
576
577 // create a new array of vtable_indices for default methods
578 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
579 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
580 assert(default_vtable_indices() == nullptr, "only create once");
581 set_default_vtable_indices(vtable_indices);
582 return vtable_indices;
583 }
584
585
586 InstanceKlass::InstanceKlass() {
587 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
588 }
589
590 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, markWord prototype_header, ReferenceType reference_type) :
591 Klass(kind, prototype_header),
592 _nest_members(nullptr),
593 _nest_host(nullptr),
594 _permitted_subclasses(nullptr),
595 _record_components(nullptr),
596 _static_field_size(parser.static_field_size()),
597 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
598 _itable_len(parser.itable_size()),
599 _nest_host_index(0),
600 _init_state(allocated),
601 _reference_type(reference_type),
602 _init_thread(nullptr),
603 _inline_layout_info_array(nullptr),
604 _loadable_descriptors(nullptr),
605 _adr_inlineklass_fixed_block(nullptr)
606 {
607 set_vtable_length(parser.vtable_size());
608 set_access_flags(parser.access_flags());
609 if (parser.is_hidden()) set_is_hidden();
610 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
611 false));
612 if (parser.has_inline_fields()) {
613 set_has_inline_type_fields();
614 }
615
616 assert(nullptr == _methods, "underlying memory not zeroed?");
617 assert(is_instance_klass(), "is layout incorrect?");
618 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
619 }
620
621 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
622 Array<Method*>* methods) {
623 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
624 !methods->is_shared()) {
625 for (int i = 0; i < methods->length(); i++) {
626 Method* method = methods->at(i);
627 if (method == nullptr) continue; // maybe null if error processing
628 // Only want to delete methods that are not executing for RedefineClasses.
629 // The previous version will point to them so they're not totally dangling
630 assert (!method->on_stack(), "shouldn't be called with methods on stack");
631 MetadataFactory::free_metadata(loader_data, method);
632 }
633 MetadataFactory::free_array<Method*>(loader_data, methods);
634 }
635 }
636
637 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
638 const Klass* super_klass,
639 Array<InstanceKlass*>* local_interfaces,
640 Array<InstanceKlass*>* transitive_interfaces) {
641 // Only deallocate transitive interfaces if not empty, same as super class
642 // or same as local interfaces. See code in parseClassFile.
643 Array<InstanceKlass*>* ti = transitive_interfaces;
644 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
645 // check that the interfaces don't come from super class
646 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
647 InstanceKlass::cast(super_klass)->transitive_interfaces();
648 if (ti != sti && ti != nullptr && !ti->is_shared()) {
649 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
650 }
651 }
652
653 // local interfaces can be empty
654 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
655 local_interfaces != nullptr && !local_interfaces->is_shared()) {
656 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
657 }
658 }
659
660 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
661 Array<RecordComponent*>* record_components) {
662 if (record_components != nullptr && !record_components->is_shared()) {
663 for (int i = 0; i < record_components->length(); i++) {
664 RecordComponent* record_component = record_components->at(i);
665 MetadataFactory::free_metadata(loader_data, record_component);
666 }
667 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
668 }
669 }
670
671 // This function deallocates the metadata and C heap pointers that the
672 // InstanceKlass points to.
673 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
674 // Orphan the mirror first, CMS thinks it's still live.
675 if (java_mirror() != nullptr) {
676 java_lang_Class::set_klass(java_mirror(), nullptr);
677 }
678
679 // Also remove mirror from handles
680 loader_data->remove_handle(_java_mirror);
681
682 // Need to take this class off the class loader data list.
683 loader_data->remove_class(this);
684
685 // The array_klass for this class is created later, after error handling.
686 // For class redefinition, we keep the original class so this scratch class
687 // doesn't have an array class. Either way, assert that there is nothing
688 // to deallocate.
689 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
690
691 // Release C heap allocated data that this points to, which includes
692 // reference counting symbol names.
693 // Can't release the constant pool or MethodData C heap data here because the constant
694 // pool can be deallocated separately from the InstanceKlass for default methods and
695 // redefine classes. MethodData can also be released separately.
696 release_C_heap_structures(/* release_sub_metadata */ false);
697
698 deallocate_methods(loader_data, methods());
699 set_methods(nullptr);
700
701 deallocate_record_components(loader_data, record_components());
702 set_record_components(nullptr);
703
704 if (method_ordering() != nullptr &&
705 method_ordering() != Universe::the_empty_int_array() &&
706 !method_ordering()->is_shared()) {
707 MetadataFactory::free_array<int>(loader_data, method_ordering());
708 }
709 set_method_ordering(nullptr);
710
711 // default methods can be empty
712 if (default_methods() != nullptr &&
713 default_methods() != Universe::the_empty_method_array() &&
714 !default_methods()->is_shared()) {
715 MetadataFactory::free_array<Method*>(loader_data, default_methods());
716 }
717 // Do NOT deallocate the default methods, they are owned by superinterfaces.
718 set_default_methods(nullptr);
719
720 // default methods vtable indices can be empty
721 if (default_vtable_indices() != nullptr &&
722 !default_vtable_indices()->is_shared()) {
723 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
724 }
725 set_default_vtable_indices(nullptr);
726
727
728 // This array is in Klass, but remove it with the InstanceKlass since
729 // this place would be the only caller and it can share memory with transitive
730 // interfaces.
731 if (secondary_supers() != nullptr &&
732 secondary_supers() != Universe::the_empty_klass_array() &&
733 // see comments in compute_secondary_supers about the following cast
734 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
735 !secondary_supers()->is_shared()) {
736 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
737 }
738 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
739
740 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
741 set_transitive_interfaces(nullptr);
742 set_local_interfaces(nullptr);
743
744 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
745 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
746 }
747 set_fieldinfo_stream(nullptr);
748
749 if (fields_status() != nullptr && !fields_status()->is_shared()) {
750 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
751 }
752 set_fields_status(nullptr);
753
754 if (inline_layout_info_array() != nullptr) {
755 MetadataFactory::free_array<InlineLayoutInfo>(loader_data, inline_layout_info_array());
756 }
757 set_inline_layout_info_array(nullptr);
758
759 // If a method from a redefined class is using this constant pool, don't
760 // delete it, yet. The new class's previous version will point to this.
761 if (constants() != nullptr) {
762 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
763 if (!constants()->is_shared()) {
764 MetadataFactory::free_metadata(loader_data, constants());
765 }
766 // Delete any cached resolution errors for the constant pool
767 SystemDictionary::delete_resolution_error(constants());
768
769 set_constants(nullptr);
770 }
771
772 if (inner_classes() != nullptr &&
773 inner_classes() != Universe::the_empty_short_array() &&
774 !inner_classes()->is_shared()) {
775 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
776 }
777 set_inner_classes(nullptr);
778
779 if (nest_members() != nullptr &&
780 nest_members() != Universe::the_empty_short_array() &&
781 !nest_members()->is_shared()) {
782 MetadataFactory::free_array<jushort>(loader_data, nest_members());
783 }
784 set_nest_members(nullptr);
785
786 if (permitted_subclasses() != nullptr &&
787 permitted_subclasses() != Universe::the_empty_short_array() &&
788 !permitted_subclasses()->is_shared()) {
789 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
790 }
791 set_permitted_subclasses(nullptr);
792
793 if (loadable_descriptors() != nullptr &&
794 loadable_descriptors() != Universe::the_empty_short_array() &&
795 !loadable_descriptors()->is_shared()) {
796 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
797 }
798 set_loadable_descriptors(nullptr);
799
800 // We should deallocate the Annotations instance if it's not in shared spaces.
801 if (annotations() != nullptr && !annotations()->is_shared()) {
802 MetadataFactory::free_metadata(loader_data, annotations());
803 }
804 set_annotations(nullptr);
805
806 SystemDictionaryShared::handle_class_unloading(this);
807
808 #if INCLUDE_CDS_JAVA_HEAP
809 if (CDSConfig::is_dumping_heap()) {
810 HeapShared::remove_scratch_objects(this);
811 }
812 #endif
813 }
814
815 bool InstanceKlass::is_record() const {
816 return _record_components != nullptr &&
817 is_final() &&
818 java_super() == vmClasses::Record_klass();
819 }
820
821 bool InstanceKlass::is_sealed() const {
822 return _permitted_subclasses != nullptr &&
823 _permitted_subclasses != Universe::the_empty_short_array();
824 }
825
826 // JLS 8.9: An enum class is either implicitly final and derives
827 // from java.lang.Enum, or else is implicitly sealed to its
828 // anonymous subclasses. This query detects both kinds.
829 // It does not validate the finality or
830 // sealing conditions: it merely checks for a super of Enum.
831 // This is sufficient for recognizing well-formed enums.
832 bool InstanceKlass::is_enum_subclass() const {
833 InstanceKlass* s = java_super();
834 return (s == vmClasses::Enum_klass() ||
835 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
836 }
837
838 bool InstanceKlass::should_be_initialized() const {
839 return !is_initialized();
840 }
841
842 klassItable InstanceKlass::itable() const {
843 return klassItable(const_cast<InstanceKlass*>(this));
844 }
845
846 // JVMTI spec thinks there are signers and protection domain in the
847 // instanceKlass. These accessors pretend these fields are there.
848 // The hprof specification also thinks these fields are in InstanceKlass.
849 oop InstanceKlass::protection_domain() const {
850 // return the protection_domain from the mirror
851 return java_lang_Class::protection_domain(java_mirror());
852 }
853
854 objArrayOop InstanceKlass::signers() const {
855 // return the signers from the mirror
856 return java_lang_Class::signers(java_mirror());
857 }
858
859 oop InstanceKlass::init_lock() const {
860 // return the init lock from the mirror
861 oop lock = java_lang_Class::init_lock(java_mirror());
862 // Prevent reordering with any access of initialization state
863 OrderAccess::loadload();
864 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
865 "only fully initialized state can have a null lock");
866 return lock;
867 }
868
869 // Set the initialization lock to null so the object can be GC'ed. Any racing
870 // threads to get this lock will see a null lock and will not lock.
871 // That's okay because they all check for initialized state after getting
872 // the lock and return.
873 void InstanceKlass::fence_and_clear_init_lock() {
874 // make sure previous stores are all done, notably the init_state.
875 OrderAccess::storestore();
876 java_lang_Class::clear_init_lock(java_mirror());
877 assert(!is_not_initialized(), "class must be initialized now");
878 }
879
880
881 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
882 // process. The step comments refers to the procedure described in that section.
883 // Note: implementation moved to static method to expose the this pointer.
884 void InstanceKlass::initialize(TRAPS) {
885 if (this->should_be_initialized()) {
886 initialize_impl(CHECK);
887 // Note: at this point the class may be initialized
888 // OR it may be in the state of being initialized
889 // in case of recursive initialization!
890 } else {
891 assert(is_initialized(), "sanity check");
892 }
893 }
894
895 #ifdef ASSERT
896 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
897 assert(has_aot_initialized_mirror(), "must be");
898
899 InstanceKlass* s = java_super();
900 if (s != nullptr) {
901 DEBUG_ONLY(ResourceMark rm);
902 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
903 s->external_name(), external_name());
904 s->assert_no_clinit_will_run_for_aot_initialized_class();
905 }
906
907 Array<InstanceKlass*>* interfaces = local_interfaces();
908 int len = interfaces->length();
909 for (int i = 0; i < len; i++) {
910 InstanceKlass* intf = interfaces->at(i);
911 if (!intf->is_initialized()) {
912 ResourceMark rm;
913 // Note: an interface needs to be marked as is_initialized() only if
914 // - it has a <clinit>
915 // - it has declared a default method.
916 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
917 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
918 intf->external_name(), external_name());
919 }
920 }
921 }
922 #endif
923
924 #if INCLUDE_CDS
925 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
926 assert(has_aot_initialized_mirror(), "must be");
927 assert(CDSConfig::is_loading_heap(), "must be");
928 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
929 assert_no_clinit_will_run_for_aot_initialized_class();
930
931 if (is_initialized()) {
932 return;
933 }
934
935 if (log_is_enabled(Info, cds, init)) {
936 ResourceMark rm;
937 log_info(cds, init)("%s (aot-inited)", external_name());
938 }
939
940 link_class(CHECK);
941
942 #ifdef ASSERT
943 {
944 Handle h_init_lock(THREAD, init_lock());
945 ObjectLocker ol(h_init_lock, THREAD);
946 assert(!is_initialized(), "sanity");
947 assert(!is_being_initialized(), "sanity");
948 assert(!is_in_error_state(), "sanity");
949 }
950 #endif
951
952 set_init_thread(THREAD);
953 AOTClassInitializer::call_runtime_setup(THREAD, this);
954 set_initialization_state_and_notify(fully_initialized, CHECK);
955 }
956 #endif
957
958 bool InstanceKlass::verify_code(TRAPS) {
959 // 1) Verify the bytecodes
960 return Verifier::verify(this, should_verify_class(), THREAD);
961 }
962
963 void InstanceKlass::link_class(TRAPS) {
964 assert(is_loaded(), "must be loaded");
965 if (!is_linked()) {
966 link_class_impl(CHECK);
967 }
968 }
969
970 // Called to verify that a class can link during initialization, without
971 // throwing a VerifyError.
972 bool InstanceKlass::link_class_or_fail(TRAPS) {
973 assert(is_loaded(), "must be loaded");
974 if (!is_linked()) {
975 link_class_impl(CHECK_false);
976 }
977 return is_linked();
978 }
979
980 bool InstanceKlass::link_class_impl(TRAPS) {
981 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
982 // This is for CDS static dump only -- we use the in_error_state to indicate that
983 // the class has failed verification. Throwing the NoClassDefFoundError here is just
984 // a convenient way to stop repeat attempts to verify the same (bad) class.
985 //
986 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
987 // if we are executing Java code. This is not a problem for CDS dumping phase since
988 // it doesn't execute any Java code.
989 ResourceMark rm(THREAD);
990 // Names are all known to be < 64k so we know this formatted message is not excessively large.
991 Exceptions::fthrow(THREAD_AND_LOCATION,
992 vmSymbols::java_lang_NoClassDefFoundError(),
993 "Class %s, or one of its supertypes, failed class initialization",
994 external_name());
995 return false;
996 }
997 // return if already verified
998 if (is_linked()) {
999 return true;
1000 }
1001
1002 // Timing
1003 // timer handles recursion
1004 JavaThread* jt = THREAD;
1005
1006 // link super class before linking this class
1007 Klass* super_klass = super();
1008 if (super_klass != nullptr) {
1009 if (super_klass->is_interface()) { // check if super class is an interface
1010 ResourceMark rm(THREAD);
1011 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1012 Exceptions::fthrow(
1013 THREAD_AND_LOCATION,
1014 vmSymbols::java_lang_IncompatibleClassChangeError(),
1015 "class %s has interface %s as super class",
1016 external_name(),
1017 super_klass->external_name()
1018 );
1019 return false;
1020 }
1021
1022 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
1023 ik_super->link_class_impl(CHECK_false);
1024 }
1025
1026 // link all interfaces implemented by this class before linking this class
1027 Array<InstanceKlass*>* interfaces = local_interfaces();
1028 int num_interfaces = interfaces->length();
1029 for (int index = 0; index < num_interfaces; index++) {
1030 InstanceKlass* interk = interfaces->at(index);
1031 interk->link_class_impl(CHECK_false);
1032 }
1033
1034
1035 // If a class declares a method that uses an inline class as an argument
1036 // type or return inline type, this inline class must be loaded during the
1037 // linking of this class because size and properties of the inline class
1038 // must be known in order to be able to perform inline type optimizations.
1039 // The implementation below is an approximation of this rule, the code
1040 // iterates over all methods of the current class (including overridden
1041 // methods), not only the methods declared by this class. This
1042 // approximation makes the code simpler, and doesn't change the semantic
1043 // because classes declaring methods overridden by the current class are
1044 // linked (and have performed their own pre-loading) before the linking
1045 // of the current class.
1046
1047
1048 // Note:
1049 // Inline class types are loaded during
1050 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
1051 // Inline class types used as element types for array creation
1052 // are not pre-loaded. Their loading is triggered by either anewarray
1053 // or multianewarray bytecodes.
1054
1055 // Could it be possible to do the following processing only if the
1056 // class uses inline types?
1057 if (EnableValhalla) {
1058 ResourceMark rm(THREAD);
1059 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1060 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) {
1061 assert(fs.access_flags().is_strict(), "null-free fields must be strict");
1062 Symbol* sig = fs.signature();
1063 TempNewSymbol s = Signature::strip_envelope(sig);
1064 if (s != name()) {
1065 log_info(class, preload)("Preloading class %s during linking of class %s. Cause: a null-free static field is declared with this type", s->as_C_string(), name()->as_C_string());
1066 Klass* klass = SystemDictionary::resolve_or_fail(s,
1067 Handle(THREAD, class_loader()), true,
1068 CHECK_false);
1069 if (HAS_PENDING_EXCEPTION) {
1070 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s",
1071 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string());
1072 return false; // Exception is still pending
1073 }
1074 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded",
1075 s->as_C_string(), name()->as_C_string());
1076 assert(klass != nullptr, "Sanity check");
1077 if (klass->is_abstract()) {
1078 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
1079 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class",
1080 name()->as_C_string(),
1081 InstanceKlass::cast(klass)->external_name()), false);
1082 }
1083 if (!klass->is_inline_klass()) {
1084 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
1085 err_msg("class %s expects class %s to be a value class but it is an identity class",
1086 name()->as_C_string(), klass->external_name()), false);
1087 }
1088 InlineKlass* vk = InlineKlass::cast(klass);
1089 // the inline_type_field_klasses_array might have been loaded with CDS, so update only if not already set and check consistency
1090 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
1091 if (li->klass() == nullptr) {
1092 li->set_klass(InlineKlass::cast(vk));
1093 li->set_kind(LayoutKind::REFERENCE);
1094 }
1095 assert(get_inline_type_field_klass(fs.index()) == vk, "Must match");
1096 } else {
1097 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
1098 if (li->klass() == nullptr) {
1099 li->set_klass(InlineKlass::cast(this));
1100 li->set_kind(LayoutKind::REFERENCE);
1101 }
1102 assert(get_inline_type_field_klass(fs.index()) == this, "Must match");
1103 }
1104 }
1105 }
1106
1107 // Aggressively preloading all classes from the LoadableDescriptors attribute
1108 if (loadable_descriptors() != nullptr) {
1109 HandleMark hm(THREAD);
1110 for (int i = 0; i < loadable_descriptors()->length(); i++) {
1111 Symbol* sig = constants()->symbol_at(loadable_descriptors()->at(i));
1112 if (!Signature::has_envelope(sig)) continue;
1113 TempNewSymbol class_name = Signature::strip_envelope(sig);
1114 if (class_name == name()) continue;
1115 log_info(class, preload)("Preloading class %s during linking of class %s because of the class is listed in the LoadableDescriptors attribute", sig->as_C_string(), name()->as_C_string());
1116 oop loader = class_loader();
1117 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1118 Handle(THREAD, loader), THREAD);
1119 if (HAS_PENDING_EXCEPTION) {
1120 CLEAR_PENDING_EXCEPTION;
1121 }
1122 if (klass != nullptr) {
1123 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) succeeded", class_name->as_C_string(), name()->as_C_string());
1124 if (!klass->is_inline_klass()) {
1125 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning
1126 log_warning(class, preload)("Preloading class %s during linking of class %s (cause: LoadableDescriptors attribute) but loaded class is not a value class", class_name->as_C_string(), name()->as_C_string());
1127 }
1128 } else {
1129 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) failed", class_name->as_C_string(), name()->as_C_string());
1130 }
1131 }
1132 }
1133 }
1134
1135 // in case the class is linked in the process of linking its superclasses
1136 if (is_linked()) {
1137 return true;
1138 }
1139
1140 // trace only the link time for this klass that includes
1141 // the verification time
1142 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1143 ClassLoader::perf_class_link_selftime(),
1144 ClassLoader::perf_classes_linked(),
1145 jt->get_thread_stat()->perf_recursion_counts_addr(),
1146 jt->get_thread_stat()->perf_timers_addr(),
1147 PerfClassTraceTime::CLASS_LINK);
1148
1149 // verification & rewriting
1150 {
1151 HandleMark hm(THREAD);
1152 Handle h_init_lock(THREAD, init_lock());
1153 ObjectLocker ol(h_init_lock, jt);
1154 // rewritten will have been set if loader constraint error found
1155 // on an earlier link attempt
1156 // don't verify or rewrite if already rewritten
1157 //
1158
1159 if (!is_linked()) {
1160 if (!is_rewritten()) {
1161 if (is_shared()) {
1162 assert(!verified_at_dump_time(), "must be");
1163 }
1164 {
1165 bool verify_ok = verify_code(THREAD);
1166 if (!verify_ok) {
1167 return false;
1168 }
1169 }
1170
1171 // Just in case a side-effect of verify linked this class already
1172 // (which can sometimes happen since the verifier loads classes
1173 // using custom class loaders, which are free to initialize things)
1174 if (is_linked()) {
1175 return true;
1176 }
1177
1178 // also sets rewritten
1179 rewrite_class(CHECK_false);
1180 } else if (is_shared()) {
1181 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1182 }
1183
1184 // relocate jsrs and link methods after they are all rewritten
1185 link_methods(CHECK_false);
1186
1187 // Initialize the vtable and interface table after
1188 // methods have been rewritten since rewrite may
1189 // fabricate new Method*s.
1190 // also does loader constraint checking
1191 //
1192 // initialize_vtable and initialize_itable need to be rerun
1193 // for a shared class if
1194 // 1) the class is loaded by custom class loader or
1195 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1196 // 3) the class was not verified during dump time
1197 bool need_init_table = true;
1198 if (is_shared() && verified_at_dump_time() &&
1199 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1200 need_init_table = false;
1201 }
1202 if (need_init_table) {
1203 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1204 itable().initialize_itable_and_check_constraints(CHECK_false);
1205 }
1206 #ifdef ASSERT
1207 vtable().verify(tty, true);
1208 // In case itable verification is ever added.
1209 // itable().verify(tty, true);
1210 #endif
1211 if (Universe::is_fully_initialized()) {
1212 DeoptimizationScope deopt_scope;
1213 {
1214 // Now mark all code that assumes the class is not linked.
1215 // Set state under the Compile_lock also.
1216 MutexLocker ml(THREAD, Compile_lock);
1217
1218 set_init_state(linked);
1219 CodeCache::mark_dependents_on(&deopt_scope, this);
1220 }
1221 // Perform the deopt handshake outside Compile_lock.
1222 deopt_scope.deoptimize_marked();
1223 } else {
1224 set_init_state(linked);
1225 }
1226 if (JvmtiExport::should_post_class_prepare()) {
1227 JvmtiExport::post_class_prepare(THREAD, this);
1228 }
1229 }
1230 }
1231 return true;
1232 }
1233
1234 // Rewrite the byte codes of all of the methods of a class.
1235 // The rewriter must be called exactly once. Rewriting must happen after
1236 // verification but before the first method of the class is executed.
1237 void InstanceKlass::rewrite_class(TRAPS) {
1238 assert(is_loaded(), "must be loaded");
1239 if (is_rewritten()) {
1240 assert(is_shared(), "rewriting an unshared class?");
1241 return;
1242 }
1243 Rewriter::rewrite(this, CHECK);
1244 set_rewritten();
1245 }
1246
1247 // Now relocate and link method entry points after class is rewritten.
1248 // This is outside is_rewritten flag. In case of an exception, it can be
1249 // executed more than once.
1250 void InstanceKlass::link_methods(TRAPS) {
1251 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1252
1253 int len = methods()->length();
1254 for (int i = len-1; i >= 0; i--) {
1255 methodHandle m(THREAD, methods()->at(i));
1256
1257 // Set up method entry points for compiler and interpreter .
1258 m->link_method(m, CHECK);
1259 }
1260 }
1261
1262 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1263 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1264 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1265 for (int i = 0; i < local_interfaces()->length(); ++i) {
1266 InstanceKlass* ik = local_interfaces()->at(i);
1267
1268 // Initialization is depth first search ie. we start with top of the inheritance tree
1269 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1270 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1271 if (ik->has_nonstatic_concrete_methods()) {
1272 ik->initialize_super_interfaces(CHECK);
1273 }
1274
1275 // Only initialize() interfaces that "declare" concrete methods.
1276 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1277 ik->initialize(CHECK);
1278 }
1279 }
1280 }
1281
1282 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1283 static InitializationErrorTable* _initialization_error_table;
1284
1285 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1286 // Create the same exception with a message indicating the thread name,
1287 // and the StackTraceElements.
1288 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1289 ResourceMark rm(current);
1290 if (init_error.is_null()) {
1291 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1292
1293 // We failed to create the new exception, most likely due to either out-of-memory or
1294 // a stackoverflow error. If the original exception was either of those then we save
1295 // the shared, pre-allocated, stackless, instance of that exception.
1296 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1297 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1298 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1299 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1300 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1301 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1302 } else {
1303 return;
1304 }
1305 }
1306
1307 MutexLocker ml(current, ClassInitError_lock);
1308 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1309 bool created;
1310 if (_initialization_error_table == nullptr) {
1311 _initialization_error_table = new (mtClass) InitializationErrorTable();
1312 }
1313 _initialization_error_table->put_if_absent(this, elem, &created);
1314 assert(created, "Initialization is single threaded");
1315 log_trace(class, init)("Initialization error added for class %s", external_name());
1316 }
1317
1318 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1319 MutexLocker ml(current, ClassInitError_lock);
1320 if (_initialization_error_table == nullptr) {
1321 return nullptr;
1322 }
1323 OopHandle* h = _initialization_error_table->get(this);
1324 return (h != nullptr) ? h->resolve() : nullptr;
1325 }
1326
1327 // Need to remove entries for unloaded classes.
1328 void InstanceKlass::clean_initialization_error_table() {
1329 struct InitErrorTableCleaner {
1330 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1331 if (!ik->is_loader_alive()) {
1332 h.release(Universe::vm_global());
1333 return true;
1334 } else {
1335 return false;
1336 }
1337 }
1338 };
1339
1340 assert_locked_or_safepoint(ClassInitError_lock);
1341 InitErrorTableCleaner cleaner;
1342 if (_initialization_error_table != nullptr) {
1343 _initialization_error_table->unlink(&cleaner);
1344 }
1345 }
1346
1347 void InstanceKlass::initialize_impl(TRAPS) {
1348 HandleMark hm(THREAD);
1349
1350 // Make sure klass is linked (verified) before initialization
1351 // A class could already be verified, since it has been reflected upon.
1352 link_class(CHECK);
1353
1354 DTRACE_CLASSINIT_PROBE(required, -1);
1355
1356 bool wait = false;
1357
1358 JavaThread* jt = THREAD;
1359
1360 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1361
1362 // refer to the JVM book page 47 for description of steps
1363 // Step 1
1364 {
1365 Handle h_init_lock(THREAD, init_lock());
1366 ObjectLocker ol(h_init_lock, jt);
1367
1368 // Step 2
1369 // If we were to use wait() instead of waitInterruptibly() then
1370 // we might end up throwing IE from link/symbol resolution sites
1371 // that aren't expected to throw. This would wreak havoc. See 6320309.
1372 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1373 if (debug_logging_enabled) {
1374 ResourceMark rm(jt);
1375 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1376 jt->name(), external_name(), init_thread_name());
1377 }
1378 wait = true;
1379 jt->set_class_to_be_initialized(this);
1380 ol.wait_uninterruptibly(jt);
1381 jt->set_class_to_be_initialized(nullptr);
1382 }
1383
1384 // Step 3
1385 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1386 if (debug_logging_enabled) {
1387 ResourceMark rm(jt);
1388 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1389 jt->name(), external_name());
1390 }
1391 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1392 return;
1393 }
1394
1395 // Step 4
1396 if (is_initialized()) {
1397 if (debug_logging_enabled) {
1398 ResourceMark rm(jt);
1399 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1400 jt->name(), external_name());
1401 }
1402 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1403 return;
1404 }
1405
1406 // Step 5
1407 if (is_in_error_state()) {
1408 if (debug_logging_enabled) {
1409 ResourceMark rm(jt);
1410 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1411 jt->name(), external_name());
1412 }
1413
1414 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1415 ResourceMark rm(THREAD);
1416 Handle cause(THREAD, get_initialization_error(THREAD));
1417
1418 stringStream ss;
1419 ss.print("Could not initialize class %s", external_name());
1420 if (cause.is_null()) {
1421 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1422 } else {
1423 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1424 ss.as_string(), cause);
1425 }
1426 } else {
1427
1428 // Step 6
1429 set_init_state(being_initialized);
1430 set_init_thread(jt);
1431 if (debug_logging_enabled) {
1432 ResourceMark rm(jt);
1433 log_debug(class, init)("Thread \"%s\" is initializing %s",
1434 jt->name(), external_name());
1435 }
1436 }
1437 }
1438
1439 // Pre-allocating an all-zero value to be used to reset nullable flat storages
1440 if (is_inline_klass()) {
1441 InlineKlass* vk = InlineKlass::cast(this);
1442 if (vk->has_nullable_atomic_layout()) {
1443 oop val = vk->allocate_instance(THREAD);
1444 if (HAS_PENDING_EXCEPTION) {
1445 Handle e(THREAD, PENDING_EXCEPTION);
1446 CLEAR_PENDING_EXCEPTION;
1447 {
1448 EXCEPTION_MARK;
1449 add_initialization_error(THREAD, e);
1450 // Locks object, set state, and notify all waiting threads
1451 set_initialization_state_and_notify(initialization_error, THREAD);
1452 CLEAR_PENDING_EXCEPTION;
1453 }
1454 THROW_OOP(e());
1455 }
1456 vk->set_null_reset_value(val);
1457 }
1458 }
1459
1460 // Step 7
1461 // Next, if C is a class rather than an interface, initialize it's super class and super
1462 // interfaces.
1463 if (!is_interface()) {
1464 Klass* super_klass = super();
1465 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1466 super_klass->initialize(THREAD);
1467 }
1468 // If C implements any interface that declares a non-static, concrete method,
1469 // the initialization of C triggers initialization of its super interfaces.
1470 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1471 // having a superinterface that declares, non-static, concrete methods
1472 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1473 initialize_super_interfaces(THREAD);
1474 }
1475
1476 // If any exceptions, complete abruptly, throwing the same exception as above.
1477 if (HAS_PENDING_EXCEPTION) {
1478 Handle e(THREAD, PENDING_EXCEPTION);
1479 CLEAR_PENDING_EXCEPTION;
1480 {
1481 EXCEPTION_MARK;
1482 add_initialization_error(THREAD, e);
1483 // Locks object, set state, and notify all waiting threads
1484 set_initialization_state_and_notify(initialization_error, THREAD);
1485 CLEAR_PENDING_EXCEPTION;
1486 }
1487 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1488 THROW_OOP(e());
1489 }
1490 }
1491
1492 // Step 8
1493 {
1494 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1495 if (class_initializer() != nullptr) {
1496 // Timer includes any side effects of class initialization (resolution,
1497 // etc), but not recursive entry into call_class_initializer().
1498 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1499 ClassLoader::perf_class_init_selftime(),
1500 ClassLoader::perf_classes_inited(),
1501 jt->get_thread_stat()->perf_recursion_counts_addr(),
1502 jt->get_thread_stat()->perf_timers_addr(),
1503 PerfClassTraceTime::CLASS_CLINIT);
1504 call_class_initializer(THREAD);
1505 } else {
1506 // The elapsed time is so small it's not worth counting.
1507 if (UsePerfData) {
1508 ClassLoader::perf_classes_inited()->inc();
1509 }
1510 call_class_initializer(THREAD);
1511 }
1512 }
1513
1514 // Step 9
1515 if (!HAS_PENDING_EXCEPTION) {
1516 set_initialization_state_and_notify(fully_initialized, CHECK);
1517 debug_only(vtable().verify(tty, true);)
1518 }
1519 else {
1520 // Step 10 and 11
1521 Handle e(THREAD, PENDING_EXCEPTION);
1522 CLEAR_PENDING_EXCEPTION;
1523 // JVMTI has already reported the pending exception
1524 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1525 JvmtiExport::clear_detected_exception(jt);
1526 {
1527 EXCEPTION_MARK;
1528 add_initialization_error(THREAD, e);
1529 set_initialization_state_and_notify(initialization_error, THREAD);
1530 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1531 // JVMTI has already reported the pending exception
1532 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1533 JvmtiExport::clear_detected_exception(jt);
1534 }
1535 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1536 if (e->is_a(vmClasses::Error_klass())) {
1537 THROW_OOP(e());
1538 } else {
1539 JavaCallArguments args(e);
1540 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1541 vmSymbols::throwable_void_signature(),
1542 &args);
1543 }
1544 }
1545 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1546 }
1547
1548
1549 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1550 Handle h_init_lock(THREAD, init_lock());
1551 if (h_init_lock() != nullptr) {
1552 ObjectLocker ol(h_init_lock, THREAD);
1553 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1554 set_init_state(state);
1555 fence_and_clear_init_lock();
1556 ol.notify_all(CHECK);
1557 } else {
1558 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1559 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1560 set_init_state(state);
1561 }
1562 }
1563
1564 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1565 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1566 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1567 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1568
1569 DeoptimizationScope deopt_scope;
1570 {
1571 MutexLocker ml(current, Compile_lock);
1572
1573 set_init_state(InstanceKlass::loaded);
1574 // make sure init_state store is already done.
1575 // The compiler reads the hierarchy outside of the Compile_lock.
1576 // Access ordering is used to add to hierarchy.
1577
1578 // Link into hierarchy.
1579 append_to_sibling_list(); // add to superklass/sibling list
1580 process_interfaces(); // handle all "implements" declarations
1581
1582 // Now mark all code that depended on old class hierarchy.
1583 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1584 if (Universe::is_fully_initialized()) {
1585 CodeCache::mark_dependents_on(&deopt_scope, this);
1586 }
1587 }
1588 // Perform the deopt handshake outside Compile_lock.
1589 deopt_scope.deoptimize_marked();
1590 }
1591
1592
1593 InstanceKlass* InstanceKlass::implementor() const {
1594 InstanceKlass* volatile* ik = adr_implementor();
1595 if (ik == nullptr) {
1596 return nullptr;
1597 } else {
1598 // This load races with inserts, and therefore needs acquire.
1599 InstanceKlass* ikls = Atomic::load_acquire(ik);
1600 if (ikls != nullptr && !ikls->is_loader_alive()) {
1601 return nullptr; // don't return unloaded class
1602 } else {
1603 return ikls;
1604 }
1605 }
1606 }
1607
1608
1609 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1610 assert_locked_or_safepoint(Compile_lock);
1611 assert(is_interface(), "not interface");
1612 InstanceKlass* volatile* addr = adr_implementor();
1613 assert(addr != nullptr, "null addr");
1614 if (addr != nullptr) {
1615 Atomic::release_store(addr, ik);
1616 }
1617 }
1618
1619 int InstanceKlass::nof_implementors() const {
1620 InstanceKlass* ik = implementor();
1621 if (ik == nullptr) {
1622 return 0;
1623 } else if (ik != this) {
1624 return 1;
1625 } else {
1626 return 2;
1627 }
1628 }
1629
1630 // The embedded _implementor field can only record one implementor.
1631 // When there are more than one implementors, the _implementor field
1632 // is set to the interface Klass* itself. Following are the possible
1633 // values for the _implementor field:
1634 // null - no implementor
1635 // implementor Klass* - one implementor
1636 // self - more than one implementor
1637 //
1638 // The _implementor field only exists for interfaces.
1639 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1640 if (Universe::is_fully_initialized()) {
1641 assert_lock_strong(Compile_lock);
1642 }
1643 assert(is_interface(), "not interface");
1644 // Filter out my subinterfaces.
1645 // (Note: Interfaces are never on the subklass list.)
1646 if (ik->is_interface()) return;
1647
1648 // Filter out subclasses whose supers already implement me.
1649 // (Note: CHA must walk subclasses of direct implementors
1650 // in order to locate indirect implementors.)
1651 InstanceKlass* super_ik = ik->java_super();
1652 if (super_ik != nullptr && super_ik->implements_interface(this))
1653 // We only need to check one immediate superclass, since the
1654 // implements_interface query looks at transitive_interfaces.
1655 // Any supers of the super have the same (or fewer) transitive_interfaces.
1656 return;
1657
1658 InstanceKlass* iklass = implementor();
1659 if (iklass == nullptr) {
1660 set_implementor(ik);
1661 } else if (iklass != this && iklass != ik) {
1662 // There is already an implementor. Use itself as an indicator of
1663 // more than one implementors.
1664 set_implementor(this);
1665 }
1666
1667 // The implementor also implements the transitive_interfaces
1668 for (int index = 0; index < local_interfaces()->length(); index++) {
1669 local_interfaces()->at(index)->add_implementor(ik);
1670 }
1671 }
1672
1673 void InstanceKlass::init_implementor() {
1674 if (is_interface()) {
1675 set_implementor(nullptr);
1676 }
1677 }
1678
1679
1680 void InstanceKlass::process_interfaces() {
1681 // link this class into the implementors list of every interface it implements
1682 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1683 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1684 InstanceKlass* interf = local_interfaces()->at(i);
1685 assert(interf->is_interface(), "expected interface");
1686 interf->add_implementor(this);
1687 }
1688 }
1689
1690 bool InstanceKlass::can_be_primary_super_slow() const {
1691 if (is_interface())
1692 return false;
1693 else
1694 return Klass::can_be_primary_super_slow();
1695 }
1696
1697 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1698 Array<InstanceKlass*>* transitive_interfaces) {
1699 // The secondaries are the implemented interfaces.
1700 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1701 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1702 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1703 int num_secondaries = num_extra_slots + interfaces->length();
1704 if (num_secondaries == 0) {
1705 // Must share this for correct bootstrapping!
1706 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1707 return nullptr;
1708 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1709 // We will reuse the transitive interfaces list if we're certain
1710 // it's in hash order.
1711 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1712 set_secondary_supers(interfaces, bitmap);
1713 return nullptr;
1714 }
1715 // Copy transitive interfaces to a temporary growable array to be constructed
1716 // into the secondary super list with extra slots.
1717 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1718 for (int i = 0; i < interfaces->length(); i++) {
1719 secondaries->push(interfaces->at(i));
1720 }
1721 return secondaries;
1722 }
1723
1724 bool InstanceKlass::implements_interface(Klass* k) const {
1725 if (this == k) return true;
1726 assert(k->is_interface(), "should be an interface class");
1727 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1728 if (transitive_interfaces()->at(i) == k) {
1729 return true;
1730 }
1731 }
1732 return false;
1733 }
1734
1735 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1736 // Verify direct super interface
1737 if (this == k) return true;
1738 assert(k->is_interface(), "should be an interface class");
1739 for (int i = 0; i < local_interfaces()->length(); i++) {
1740 if (local_interfaces()->at(i) == k) {
1741 return true;
1742 }
1743 }
1744 return false;
1745 }
1746
1747 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1748 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1749 size_t size = objArrayOopDesc::object_size(length);
1750 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1751 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1752 /* do_zero */ true, CHECK_NULL);
1753 return o;
1754 }
1755
1756 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1757 if (TraceFinalizerRegistration) {
1758 tty->print("Registered ");
1759 i->print_value_on(tty);
1760 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1761 }
1762 instanceHandle h_i(THREAD, i);
1763 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1764 JavaValue result(T_VOID);
1765 JavaCallArguments args(h_i);
1766 methodHandle mh(THREAD, Universe::finalizer_register_method());
1767 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1768 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1769 return h_i();
1770 }
1771
1772 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1773 assert(!is_abstract() && !is_interface(), "Should not create this object");
1774 size_t size = size_helper(); // Query before forming handle.
1775 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1776 }
1777
1778 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1779 Klass* k = java_lang_Class::as_Klass(java_class);
1780 if (k == nullptr) {
1781 ResourceMark rm(THREAD);
1782 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1783 }
1784 InstanceKlass* ik = cast(k);
1785 ik->check_valid_for_instantiation(false, CHECK_NULL);
1786 ik->initialize(CHECK_NULL);
1787 return ik->allocate_instance(THREAD);
1788 }
1789
1790 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1791 return instanceHandle(THREAD, allocate_instance(THREAD));
1792 }
1793
1794 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1795 if (is_interface() || is_abstract()) {
1796 ResourceMark rm(THREAD);
1797 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1798 : vmSymbols::java_lang_InstantiationException(), external_name());
1799 }
1800 if (this == vmClasses::Class_klass()) {
1801 ResourceMark rm(THREAD);
1802 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1803 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1804 }
1805 }
1806
1807 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1808 // Need load-acquire for lock-free read
1809 if (array_klasses_acquire() == nullptr) {
1810
1811 // Recursively lock array allocation
1812 RecursiveLocker rl(MultiArray_lock, THREAD);
1813
1814 // Check if another thread created the array klass while we were waiting for the lock.
1815 if (array_klasses() == nullptr) {
1816 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, false, CHECK_NULL);
1817 // use 'release' to pair with lock-free load
1818 release_set_array_klasses(k);
1819 }
1820 }
1821
1822 // array_klasses() will always be set at this point
1823 ArrayKlass* ak = array_klasses();
1824 assert(ak != nullptr, "should be set");
1825 return ak->array_klass(n, THREAD);
1826 }
1827
1828 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1829 // Need load-acquire for lock-free read
1830 ArrayKlass* ak = array_klasses_acquire();
1831 if (ak == nullptr) {
1832 return nullptr;
1833 } else {
1834 return ak->array_klass_or_null(n);
1835 }
1836 }
1837
1838 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1839 return array_klass(1, THREAD);
1840 }
1841
1842 ArrayKlass* InstanceKlass::array_klass_or_null() {
1843 return array_klass_or_null(1);
1844 }
1845
1846 static int call_class_initializer_counter = 0; // for debugging
1847
1848 Method* InstanceKlass::class_initializer() const {
1849 Method* clinit = find_method(
1850 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1851 if (clinit != nullptr && clinit->is_class_initializer()) {
1852 return clinit;
1853 }
1854 return nullptr;
1855 }
1856
1857 void InstanceKlass::call_class_initializer(TRAPS) {
1858 if (ReplayCompiles &&
1859 (ReplaySuppressInitializers == 1 ||
1860 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1861 // Hide the existence of the initializer for the purpose of replaying the compile
1862 return;
1863 }
1864
1865 #if INCLUDE_CDS
1866 // This is needed to ensure the consistency of the archived heap objects.
1867 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1868 AOTClassInitializer::call_runtime_setup(THREAD, this);
1869 return;
1870 } else if (has_archived_enum_objs()) {
1871 assert(is_shared(), "must be");
1872 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1873 if (initialized) {
1874 return;
1875 }
1876 }
1877 #endif
1878
1879 methodHandle h_method(THREAD, class_initializer());
1880 assert(!is_initialized(), "we cannot initialize twice");
1881 LogTarget(Info, class, init) lt;
1882 if (lt.is_enabled()) {
1883 ResourceMark rm(THREAD);
1884 LogStream ls(lt);
1885 ls.print("%d Initializing ", call_class_initializer_counter++);
1886 name()->print_value_on(&ls);
1887 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1888 h_method() == nullptr ? "(no method)" : "", p2i(this),
1889 THREAD->name());
1890 }
1891 if (h_method() != nullptr) {
1892 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1893 JavaCallArguments args; // No arguments
1894 JavaValue result(T_VOID);
1895 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1896 }
1897 }
1898
1899 // If a class that implements this interface is initialized, is the JVM required
1900 // to first execute a <clinit> method declared in this interface,
1901 // or (if also_check_supers==true) any of the super types of this interface?
1902 //
1903 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1904 // an interface, then let SC be its superclass and let SI1, ..., SIn
1905 // be all superinterfaces of C (whether direct or indirect) that
1906 // declare at least one non-abstract, non-static method.
1907 //
1908 // So when an interface is initialized, it does not look at its
1909 // supers. But a proper class will ensure that all of its supers have
1910 // run their <clinit> methods, except that it disregards interfaces
1911 // that lack a non-static concrete method (i.e., a default method).
1912 // Therefore, you should probably call this method only when the
1913 // current class is a super of some proper class, not an interface.
1914 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1915 assert(is_interface(), "must be");
1916
1917 if (!has_nonstatic_concrete_methods()) {
1918 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1919 return false;
1920 }
1921
1922 // JVMS 5.5. Initialization
1923 // ...If C is an interface that declares a non-abstract,
1924 // non-static method, the initialization of a class that
1925 // implements C directly or indirectly.
1926 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1927 return true;
1928 }
1929 if (also_check_supers) {
1930 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1931 for (int i = 0; i < all_ifs->length(); ++i) {
1932 InstanceKlass* super_intf = all_ifs->at(i);
1933 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1934 return true;
1935 }
1936 }
1937 }
1938 return false;
1939 }
1940
1941 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1942 InterpreterOopMap* entry_for) {
1943 // Lazily create the _oop_map_cache at first request.
1944 // Load_acquire is needed to safely get instance published with CAS by another thread.
1945 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1946 if (oop_map_cache == nullptr) {
1947 // Try to install new instance atomically.
1948 oop_map_cache = new OopMapCache();
1949 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1950 if (other != nullptr) {
1951 // Someone else managed to install before us, ditch local copy and use the existing one.
1952 delete oop_map_cache;
1953 oop_map_cache = other;
1954 }
1955 }
1956 // _oop_map_cache is constant after init; lookup below does its own locking.
1957 oop_map_cache->lookup(method, bci, entry_for);
1958 }
1959
1960
1961 FieldInfo InstanceKlass::field(int index) const {
1962 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1963 if (fs.index() == index) {
1964 return fs.to_FieldInfo();
1965 }
1966 }
1967 fatal("Field not found");
1968 return FieldInfo();
1969 }
1970
1971 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1972 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1973 Symbol* f_name = fs.name();
1974 Symbol* f_sig = fs.signature();
1975 if (f_name == name && f_sig == sig) {
1976 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1977 return true;
1978 }
1979 }
1980 return false;
1981 }
1982
1983
1984 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1985 const int n = local_interfaces()->length();
1986 for (int i = 0; i < n; i++) {
1987 Klass* intf1 = local_interfaces()->at(i);
1988 assert(intf1->is_interface(), "just checking type");
1989 // search for field in current interface
1990 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1991 assert(fd->is_static(), "interface field must be static");
1992 return intf1;
1993 }
1994 // search for field in direct superinterfaces
1995 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1996 if (intf2 != nullptr) return intf2;
1997 }
1998 // otherwise field lookup fails
1999 return nullptr;
2000 }
2001
2002
2003 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2004 // search order according to newest JVM spec (5.4.3.2, p.167).
2005 // 1) search for field in current klass
2006 if (find_local_field(name, sig, fd)) {
2007 return const_cast<InstanceKlass*>(this);
2008 }
2009 // 2) search for field recursively in direct superinterfaces
2010 { Klass* intf = find_interface_field(name, sig, fd);
2011 if (intf != nullptr) return intf;
2012 }
2013 // 3) apply field lookup recursively if superclass exists
2014 { Klass* supr = super();
2015 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
2016 }
2017 // 4) otherwise field lookup fails
2018 return nullptr;
2019 }
2020
2021
2022 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
2023 // search order according to newest JVM spec (5.4.3.2, p.167).
2024 // 1) search for field in current klass
2025 if (find_local_field(name, sig, fd)) {
2026 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
2027 }
2028 // 2) search for field recursively in direct superinterfaces
2029 if (is_static) {
2030 Klass* intf = find_interface_field(name, sig, fd);
2031 if (intf != nullptr) return intf;
2032 }
2033 // 3) apply field lookup recursively if superclass exists
2034 { Klass* supr = super();
2035 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
2036 }
2037 // 4) otherwise field lookup fails
2038 return nullptr;
2039 }
2040
2041 bool InstanceKlass::contains_field_offset(int offset) {
2042 if (this->is_inline_klass()) {
2043 InlineKlass* vk = InlineKlass::cast(this);
2044 return offset >= vk->payload_offset() && offset < (vk->payload_offset() + vk->payload_size_in_bytes());
2045 } else {
2046 fieldDescriptor fd;
2047 return find_field_from_offset(offset, false, &fd);
2048 }
2049 }
2050
2051 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2052 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2053 if (fs.offset() == offset) {
2054 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
2055 if (fd->is_static() == is_static) return true;
2056 }
2057 }
2058 return false;
2059 }
2060
2061
2062 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2063 Klass* klass = const_cast<InstanceKlass*>(this);
2064 while (klass != nullptr) {
2065 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
2066 return true;
2067 }
2068 klass = klass->super();
2069 }
2070 return false;
2071 }
2072
2073
2074 void InstanceKlass::methods_do(void f(Method* method)) {
2075 // Methods aren't stable until they are loaded. This can be read outside
2076 // a lock through the ClassLoaderData for profiling
2077 // Redefined scratch classes are on the list and need to be cleaned
2078 if (!is_loaded() && !is_scratch_class()) {
2079 return;
2080 }
2081
2082 int len = methods()->length();
2083 for (int index = 0; index < len; index++) {
2084 Method* m = methods()->at(index);
2085 assert(m->is_method(), "must be method");
2086 f(m);
2087 }
2088 }
2089
2090
2091 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2092 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2093 if (fs.access_flags().is_static()) {
2094 fieldDescriptor& fd = fs.field_descriptor();
2095 cl->do_field(&fd);
2096 }
2097 }
2098 }
2099
2100
2101 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2102 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2103 if (fs.access_flags().is_static()) {
2104 fieldDescriptor& fd = fs.field_descriptor();
2105 f(&fd, mirror, CHECK);
2106 }
2107 }
2108 }
2109
2110 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2111 InstanceKlass* super = superklass();
2112 if (super != nullptr) {
2113 super->do_nonstatic_fields(cl);
2114 }
2115 fieldDescriptor fd;
2116 int length = java_fields_count();
2117 for (int i = 0; i < length; i += 1) {
2118 fd.reinitialize(this, i);
2119 if (!fd.is_static()) {
2120 cl->do_field(&fd);
2121 }
2122 }
2123 }
2124
2125 // first in Pair is offset, second is index.
2126 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2127 return a->first - b->first;
2128 }
2129
2130 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2131 InstanceKlass* super = superklass();
2132 if (super != nullptr) {
2133 super->print_nonstatic_fields(cl);
2134 }
2135 ResourceMark rm;
2136 fieldDescriptor fd;
2137 // In DebugInfo nonstatic fields are sorted by offset.
2138 GrowableArray<Pair<int,int> > fields_sorted;
2139 int i = 0;
2140 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2141 if (!fs.access_flags().is_static()) {
2142 fd = fs.field_descriptor();
2143 Pair<int,int> f(fs.offset(), fs.index());
2144 fields_sorted.push(f);
2145 i++;
2146 }
2147 }
2148 if (i > 0) {
2149 int length = i;
2150 assert(length == fields_sorted.length(), "duh");
2151 fields_sorted.sort(compare_fields_by_offset);
2152 for (int i = 0; i < length; i++) {
2153 fd.reinitialize(this, fields_sorted.at(i).second);
2154 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2155 cl->do_field(&fd);
2156 }
2157 }
2158 }
2159
2160 #ifdef ASSERT
2161 static int linear_search(const Array<Method*>* methods,
2162 const Symbol* name,
2163 const Symbol* signature) {
2164 const int len = methods->length();
2165 for (int index = 0; index < len; index++) {
2166 const Method* const m = methods->at(index);
2167 assert(m->is_method(), "must be method");
2168 if (m->signature() == signature && m->name() == name) {
2169 return index;
2170 }
2171 }
2172 return -1;
2173 }
2174 #endif
2175
2176 bool InstanceKlass::_disable_method_binary_search = false;
2177
2178 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2179 int len = methods->length();
2180 int l = 0;
2181 int h = len - 1;
2182 while (l <= h) {
2183 Method* m = methods->at(l);
2184 if (m->name() == name) {
2185 return l;
2186 }
2187 l++;
2188 }
2189 return -1;
2190 }
2191
2192 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2193 if (_disable_method_binary_search) {
2194 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2195 // At the final stage of dynamic dumping, the methods array may not be sorted
2196 // by ascending addresses of their names, so we can't use binary search anymore.
2197 // However, methods with the same name are still laid out consecutively inside the
2198 // methods array, so let's look for the first one that matches.
2199 return linear_search(methods, name);
2200 }
2201
2202 int len = methods->length();
2203 int l = 0;
2204 int h = len - 1;
2205
2206 // methods are sorted by ascending addresses of their names, so do binary search
2207 while (l <= h) {
2208 int mid = (l + h) >> 1;
2209 Method* m = methods->at(mid);
2210 assert(m->is_method(), "must be method");
2211 int res = m->name()->fast_compare(name);
2212 if (res == 0) {
2213 return mid;
2214 } else if (res < 0) {
2215 l = mid + 1;
2216 } else {
2217 h = mid - 1;
2218 }
2219 }
2220 return -1;
2221 }
2222
2223 // find_method looks up the name/signature in the local methods array
2224 Method* InstanceKlass::find_method(const Symbol* name,
2225 const Symbol* signature) const {
2226 return find_method_impl(name, signature,
2227 OverpassLookupMode::find,
2228 StaticLookupMode::find,
2229 PrivateLookupMode::find);
2230 }
2231
2232 Method* InstanceKlass::find_method_impl(const Symbol* name,
2233 const Symbol* signature,
2234 OverpassLookupMode overpass_mode,
2235 StaticLookupMode static_mode,
2236 PrivateLookupMode private_mode) const {
2237 return InstanceKlass::find_method_impl(methods(),
2238 name,
2239 signature,
2240 overpass_mode,
2241 static_mode,
2242 private_mode);
2243 }
2244
2245 // find_instance_method looks up the name/signature in the local methods array
2246 // and skips over static methods
2247 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2248 const Symbol* name,
2249 const Symbol* signature,
2250 PrivateLookupMode private_mode) {
2251 Method* const meth = InstanceKlass::find_method_impl(methods,
2252 name,
2253 signature,
2254 OverpassLookupMode::find,
2255 StaticLookupMode::skip,
2256 private_mode);
2257 assert(((meth == nullptr) || !meth->is_static()),
2258 "find_instance_method should have skipped statics");
2259 return meth;
2260 }
2261
2262 // find_instance_method looks up the name/signature in the local methods array
2263 // and skips over static methods
2264 Method* InstanceKlass::find_instance_method(const Symbol* name,
2265 const Symbol* signature,
2266 PrivateLookupMode private_mode) const {
2267 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2268 }
2269
2270 // Find looks up the name/signature in the local methods array
2271 // and filters on the overpass, static and private flags
2272 // This returns the first one found
2273 // note that the local methods array can have up to one overpass, one static
2274 // and one instance (private or not) with the same name/signature
2275 Method* InstanceKlass::find_local_method(const Symbol* name,
2276 const Symbol* signature,
2277 OverpassLookupMode overpass_mode,
2278 StaticLookupMode static_mode,
2279 PrivateLookupMode private_mode) const {
2280 return InstanceKlass::find_method_impl(methods(),
2281 name,
2282 signature,
2283 overpass_mode,
2284 static_mode,
2285 private_mode);
2286 }
2287
2288 // Find looks up the name/signature in the local methods array
2289 // and filters on the overpass, static and private flags
2290 // This returns the first one found
2291 // note that the local methods array can have up to one overpass, one static
2292 // and one instance (private or not) with the same name/signature
2293 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2294 const Symbol* name,
2295 const Symbol* signature,
2296 OverpassLookupMode overpass_mode,
2297 StaticLookupMode static_mode,
2298 PrivateLookupMode private_mode) {
2299 return InstanceKlass::find_method_impl(methods,
2300 name,
2301 signature,
2302 overpass_mode,
2303 static_mode,
2304 private_mode);
2305 }
2306
2307 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2308 const Symbol* name,
2309 const Symbol* signature) {
2310 return InstanceKlass::find_method_impl(methods,
2311 name,
2312 signature,
2313 OverpassLookupMode::find,
2314 StaticLookupMode::find,
2315 PrivateLookupMode::find);
2316 }
2317
2318 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2319 const Symbol* name,
2320 const Symbol* signature,
2321 OverpassLookupMode overpass_mode,
2322 StaticLookupMode static_mode,
2323 PrivateLookupMode private_mode) {
2324 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2325 return hit >= 0 ? methods->at(hit): nullptr;
2326 }
2327
2328 // true if method matches signature and conforms to skipping_X conditions.
2329 static bool method_matches(const Method* m,
2330 const Symbol* signature,
2331 bool skipping_overpass,
2332 bool skipping_static,
2333 bool skipping_private) {
2334 return ((m->signature() == signature) &&
2335 (!skipping_overpass || !m->is_overpass()) &&
2336 (!skipping_static || !m->is_static()) &&
2337 (!skipping_private || !m->is_private()));
2338 }
2339
2340 // Used directly for default_methods to find the index into the
2341 // default_vtable_indices, and indirectly by find_method
2342 // find_method_index looks in the local methods array to return the index
2343 // of the matching name/signature. If, overpass methods are being ignored,
2344 // the search continues to find a potential non-overpass match. This capability
2345 // is important during method resolution to prefer a static method, for example,
2346 // over an overpass method.
2347 // There is the possibility in any _method's array to have the same name/signature
2348 // for a static method, an overpass method and a local instance method
2349 // To correctly catch a given method, the search criteria may need
2350 // to explicitly skip the other two. For local instance methods, it
2351 // is often necessary to skip private methods
2352 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2353 const Symbol* name,
2354 const Symbol* signature,
2355 OverpassLookupMode overpass_mode,
2356 StaticLookupMode static_mode,
2357 PrivateLookupMode private_mode) {
2358 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2359 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2360 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2361 const int hit = quick_search(methods, name);
2362 if (hit != -1) {
2363 const Method* const m = methods->at(hit);
2364
2365 // Do linear search to find matching signature. First, quick check
2366 // for common case, ignoring overpasses if requested.
2367 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2368 return hit;
2369 }
2370
2371 // search downwards through overloaded methods
2372 int i;
2373 for (i = hit - 1; i >= 0; --i) {
2374 const Method* const m = methods->at(i);
2375 assert(m->is_method(), "must be method");
2376 if (m->name() != name) {
2377 break;
2378 }
2379 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2380 return i;
2381 }
2382 }
2383 // search upwards
2384 for (i = hit + 1; i < methods->length(); ++i) {
2385 const Method* const m = methods->at(i);
2386 assert(m->is_method(), "must be method");
2387 if (m->name() != name) {
2388 break;
2389 }
2390 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2391 return i;
2392 }
2393 }
2394 // not found
2395 #ifdef ASSERT
2396 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2397 linear_search(methods, name, signature);
2398 assert(-1 == index, "binary search should have found entry %d", index);
2399 #endif
2400 }
2401 return -1;
2402 }
2403
2404 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2405 return find_method_by_name(methods(), name, end);
2406 }
2407
2408 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2409 const Symbol* name,
2410 int* end_ptr) {
2411 assert(end_ptr != nullptr, "just checking");
2412 int start = quick_search(methods, name);
2413 int end = start + 1;
2414 if (start != -1) {
2415 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2416 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2417 *end_ptr = end;
2418 return start;
2419 }
2420 return -1;
2421 }
2422
2423 // uncached_lookup_method searches both the local class methods array and all
2424 // superclasses methods arrays, skipping any overpass methods in superclasses,
2425 // and possibly skipping private methods.
2426 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2427 const Symbol* signature,
2428 OverpassLookupMode overpass_mode,
2429 PrivateLookupMode private_mode) const {
2430 OverpassLookupMode overpass_local_mode = overpass_mode;
2431 const Klass* klass = this;
2432 while (klass != nullptr) {
2433 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2434 signature,
2435 overpass_local_mode,
2436 StaticLookupMode::find,
2437 private_mode);
2438 if (method != nullptr) {
2439 return method;
2440 }
2441 if (name == vmSymbols::object_initializer_name()) {
2442 break; // <init> is never inherited
2443 }
2444 klass = klass->super();
2445 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2446 }
2447 return nullptr;
2448 }
2449
2450 #ifdef ASSERT
2451 // search through class hierarchy and return true if this class or
2452 // one of the superclasses was redefined
2453 bool InstanceKlass::has_redefined_this_or_super() const {
2454 const Klass* klass = this;
2455 while (klass != nullptr) {
2456 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2457 return true;
2458 }
2459 klass = klass->super();
2460 }
2461 return false;
2462 }
2463 #endif
2464
2465 // lookup a method in the default methods list then in all transitive interfaces
2466 // Do NOT return private or static methods
2467 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2468 Symbol* signature) const {
2469 Method* m = nullptr;
2470 if (default_methods() != nullptr) {
2471 m = find_method(default_methods(), name, signature);
2472 }
2473 // Look up interfaces
2474 if (m == nullptr) {
2475 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2476 }
2477 return m;
2478 }
2479
2480 // lookup a method in all the interfaces that this class implements
2481 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2482 // They should only be found in the initial InterfaceMethodRef
2483 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2484 Symbol* signature,
2485 DefaultsLookupMode defaults_mode) const {
2486 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2487 int num_ifs = all_ifs->length();
2488 InstanceKlass *ik = nullptr;
2489 for (int i = 0; i < num_ifs; i++) {
2490 ik = all_ifs->at(i);
2491 Method* m = ik->lookup_method(name, signature);
2492 if (m != nullptr && m->is_public() && !m->is_static() &&
2493 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2494 return m;
2495 }
2496 }
2497 return nullptr;
2498 }
2499
2500 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2501 :_st(st), _verbose(verbose) {
2502 ResourceMark rm;
2503 _st->print("%-18s ", "KlassAddr");
2504 _st->print("%-4s ", "Size");
2505 _st->print("%-20s ", "State");
2506 _st->print("%-7s ", "Flags");
2507 _st->print("%-5s ", "ClassName");
2508 _st->cr();
2509 }
2510
2511 void PrintClassClosure::do_klass(Klass* k) {
2512 ResourceMark rm;
2513 // klass pointer
2514 _st->print(PTR_FORMAT " ", p2i(k));
2515 // klass size
2516 _st->print("%4d ", k->size());
2517 // initialization state
2518 if (k->is_instance_klass()) {
2519 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2520 } else {
2521 _st->print("%-20s ","");
2522 }
2523 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2524 char buf[10];
2525 int i = 0;
2526 if (k->has_finalizer()) buf[i++] = 'F';
2527 if (k->is_instance_klass()) {
2528 InstanceKlass* ik = InstanceKlass::cast(k);
2529 if (ik->has_final_method()) buf[i++] = 'f';
2530 if (ik->is_rewritten()) buf[i++] = 'W';
2531 if (ik->is_contended()) buf[i++] = 'C';
2532 if (ik->has_been_redefined()) buf[i++] = 'R';
2533 if (ik->is_shared()) buf[i++] = 'S';
2534 }
2535 buf[i++] = '\0';
2536 _st->print("%-7s ", buf);
2537 // klass name
2538 _st->print("%-5s ", k->external_name());
2539 // end
2540 _st->cr();
2541 if (_verbose) {
2542 k->print_on(_st);
2543 }
2544 }
2545
2546 /* jni_id_for for jfieldIds only */
2547 JNIid* InstanceKlass::jni_id_for(int offset) {
2548 MutexLocker ml(JfieldIdCreation_lock);
2549 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2550 if (probe == nullptr) {
2551 // Allocate new static field identifier
2552 probe = new JNIid(this, offset, jni_ids());
2553 set_jni_ids(probe);
2554 }
2555 return probe;
2556 }
2557
2558 u2 InstanceKlass::enclosing_method_data(int offset) const {
2559 const Array<jushort>* const inner_class_list = inner_classes();
2560 if (inner_class_list == nullptr) {
2561 return 0;
2562 }
2563 const int length = inner_class_list->length();
2564 if (length % inner_class_next_offset == 0) {
2565 return 0;
2566 }
2567 const int index = length - enclosing_method_attribute_size;
2568 assert(offset < enclosing_method_attribute_size, "invalid offset");
2569 return inner_class_list->at(index + offset);
2570 }
2571
2572 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2573 u2 method_index) {
2574 Array<jushort>* inner_class_list = inner_classes();
2575 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2576 int length = inner_class_list->length();
2577 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2578 int index = length - enclosing_method_attribute_size;
2579 inner_class_list->at_put(
2580 index + enclosing_method_class_index_offset, class_index);
2581 inner_class_list->at_put(
2582 index + enclosing_method_method_index_offset, method_index);
2583 }
2584 }
2585
2586 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2587 if (method->is_old() && !method->is_obsolete()) {
2588 // If the method passed in is old (but not obsolete), use the current version.
2589 method = method_with_idnum((int)idnum);
2590 assert(method != nullptr, "old and but not obsolete, so should exist");
2591 }
2592 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2593 Atomic::release_store(&jmeths[idnum + 1], new_id);
2594 return new_id;
2595 }
2596
2597 // Lookup or create a jmethodID.
2598 // This code is called by the VMThread and JavaThreads so the
2599 // locking has to be done very carefully to avoid deadlocks
2600 // and/or other cache consistency problems.
2601 //
2602 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2603 Method* method = method_h();
2604 int idnum = method->method_idnum();
2605 jmethodID* jmeths = methods_jmethod_ids_acquire();
2606
2607 // We use a double-check locking idiom here because this cache is
2608 // performance sensitive. In the normal system, this cache only
2609 // transitions from null to non-null which is safe because we use
2610 // release_set_methods_jmethod_ids() to advertise the new cache.
2611 // A partially constructed cache should never be seen by a racing
2612 // thread. We also use release_store() to save a new jmethodID
2613 // in the cache so a partially constructed jmethodID should never be
2614 // seen either. Cache reads of existing jmethodIDs proceed without a
2615 // lock, but cache writes of a new jmethodID requires uniqueness and
2616 // creation of the cache itself requires no leaks so a lock is
2617 // acquired in those two cases.
2618 //
2619 // If the RedefineClasses() API has been used, then this cache grows
2620 // in the redefinition safepoint.
2621
2622 if (jmeths == nullptr) {
2623 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2624 jmeths = methods_jmethod_ids_acquire();
2625 // Still null?
2626 if (jmeths == nullptr) {
2627 size_t size = idnum_allocated_count();
2628 assert(size > (size_t)idnum, "should already have space");
2629 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2630 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2631 // cache size is stored in element[0], other elements offset by one
2632 jmeths[0] = (jmethodID)size;
2633 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2634
2635 // publish jmeths
2636 release_set_methods_jmethod_ids(jmeths);
2637 return new_id;
2638 }
2639 }
2640
2641 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2642 if (id == nullptr) {
2643 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2644 id = jmeths[idnum + 1];
2645 // Still null?
2646 if (id == nullptr) {
2647 return update_jmethod_id(jmeths, method, idnum);
2648 }
2649 }
2650 return id;
2651 }
2652
2653 void InstanceKlass::update_methods_jmethod_cache() {
2654 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2655 jmethodID* cache = _methods_jmethod_ids;
2656 if (cache != nullptr) {
2657 size_t size = idnum_allocated_count();
2658 size_t old_size = (size_t)cache[0];
2659 if (old_size < size + 1) {
2660 // Allocate a larger one and copy entries to the new one.
2661 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2662 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2663 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2664 // The cache size is stored in element[0]; the other elements are offset by one.
2665 new_cache[0] = (jmethodID)size;
2666
2667 for (int i = 1; i <= (int)old_size; i++) {
2668 new_cache[i] = cache[i];
2669 }
2670 _methods_jmethod_ids = new_cache;
2671 FREE_C_HEAP_ARRAY(jmethodID, cache);
2672 }
2673 }
2674 }
2675
2676 // Figure out how many jmethodIDs haven't been allocated, and make
2677 // sure space for them is pre-allocated. This makes getting all
2678 // method ids much, much faster with classes with more than 8
2679 // methods, and has a *substantial* effect on performance with jvmti
2680 // code that loads all jmethodIDs for all classes.
2681 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2682 int new_jmeths = 0;
2683 int length = methods()->length();
2684 for (int index = start_offset; index < length; index++) {
2685 Method* m = methods()->at(index);
2686 jmethodID id = m->find_jmethod_id_or_null();
2687 if (id == nullptr) {
2688 new_jmeths++;
2689 }
2690 }
2691 if (new_jmeths != 0) {
2692 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2693 }
2694 }
2695
2696 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2697 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2698 int idnum = method->method_idnum();
2699 jmethodID* jmeths = methods_jmethod_ids_acquire();
2700 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2701 }
2702
2703 inline DependencyContext InstanceKlass::dependencies() {
2704 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2705 return dep_context;
2706 }
2707
2708 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2709 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2710 }
2711
2712 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2713 dependencies().add_dependent_nmethod(nm);
2714 }
2715
2716 void InstanceKlass::clean_dependency_context() {
2717 dependencies().clean_unloading_dependents();
2718 }
2719
2720 #ifndef PRODUCT
2721 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2722 dependencies().print_dependent_nmethods(verbose);
2723 }
2724
2725 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2726 return dependencies().is_dependent_nmethod(nm);
2727 }
2728 #endif //PRODUCT
2729
2730 void InstanceKlass::clean_weak_instanceklass_links() {
2731 clean_implementors_list();
2732 clean_method_data();
2733 }
2734
2735 void InstanceKlass::clean_implementors_list() {
2736 assert(is_loader_alive(), "this klass should be live");
2737 if (is_interface()) {
2738 assert (ClassUnloading, "only called for ClassUnloading");
2739 for (;;) {
2740 // Use load_acquire due to competing with inserts
2741 InstanceKlass* volatile* iklass = adr_implementor();
2742 assert(iklass != nullptr, "Klass must not be null");
2743 InstanceKlass* impl = Atomic::load_acquire(iklass);
2744 if (impl != nullptr && !impl->is_loader_alive()) {
2745 // null this field, might be an unloaded instance klass or null
2746 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2747 // Successfully unlinking implementor.
2748 if (log_is_enabled(Trace, class, unload)) {
2749 ResourceMark rm;
2750 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2751 }
2752 return;
2753 }
2754 } else {
2755 return;
2756 }
2757 }
2758 }
2759 }
2760
2761 void InstanceKlass::clean_method_data() {
2762 for (int m = 0; m < methods()->length(); m++) {
2763 MethodData* mdo = methods()->at(m)->method_data();
2764 if (mdo != nullptr) {
2765 mdo->clean_method_data(/*always_clean*/false);
2766 }
2767 }
2768 }
2769
2770 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2771 Klass::metaspace_pointers_do(it);
2772
2773 if (log_is_enabled(Trace, cds)) {
2774 ResourceMark rm;
2775 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2776 }
2777
2778 it->push(&_annotations);
2779 it->push((Klass**)&_array_klasses);
2780 if (!is_rewritten()) {
2781 it->push(&_constants, MetaspaceClosure::_writable);
2782 } else {
2783 it->push(&_constants);
2784 }
2785 it->push(&_inner_classes);
2786 #if INCLUDE_JVMTI
2787 it->push(&_previous_versions);
2788 #endif
2789 #if INCLUDE_CDS
2790 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2791 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2792 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2793 // The length check on the _methods is necessary because classes which don't have any
2794 // methods share the Universe::_the_empty_method_array which is in the RO region.
2795 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2796 // To handle jsr bytecode, new Method* maybe stored into _methods
2797 it->push(&_methods, MetaspaceClosure::_writable);
2798 } else {
2799 #endif
2800 it->push(&_methods);
2801 #if INCLUDE_CDS
2802 }
2803 #endif
2804 it->push(&_default_methods);
2805 it->push(&_local_interfaces);
2806 it->push(&_transitive_interfaces);
2807 it->push(&_method_ordering);
2808 if (!is_rewritten()) {
2809 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2810 } else {
2811 it->push(&_default_vtable_indices);
2812 }
2813
2814 it->push(&_fieldinfo_stream);
2815 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2816 it->push(&_fields_status, MetaspaceClosure::_writable);
2817
2818 if (itable_length() > 0) {
2819 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2820 int method_table_offset_in_words = ioe->offset()/wordSize;
2821 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2822
2823 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2824 / itableOffsetEntry::size();
2825
2826 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2827 if (ioe->interface_klass() != nullptr) {
2828 it->push(ioe->interface_klass_addr());
2829 itableMethodEntry* ime = ioe->first_method_entry(this);
2830 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2831 for (int index = 0; index < n; index ++) {
2832 it->push(ime[index].method_addr());
2833 }
2834 }
2835 }
2836 }
2837
2838 it->push(&_nest_host);
2839 it->push(&_nest_members);
2840 it->push(&_permitted_subclasses);
2841 it->push(&_loadable_descriptors);
2842 it->push(&_record_components);
2843 it->push(&_inline_layout_info_array, MetaspaceClosure::_writable);
2844 }
2845
2846 #if INCLUDE_CDS
2847 void InstanceKlass::remove_unshareable_info() {
2848
2849 if (is_linked()) {
2850 assert(can_be_verified_at_dumptime(), "must be");
2851 // Remember this so we can avoid walking the hierarchy at runtime.
2852 set_verified_at_dump_time();
2853 }
2854
2855 Klass::remove_unshareable_info();
2856
2857 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2858 // Classes are attempted to link during dumping and may fail,
2859 // but these classes are still in the dictionary and class list in CLD.
2860 // If the class has failed verification, there is nothing else to remove.
2861 return;
2862 }
2863
2864 // Reset to the 'allocated' state to prevent any premature accessing to
2865 // a shared class at runtime while the class is still being loaded and
2866 // restored. A class' init_state is set to 'loaded' at runtime when it's
2867 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2868 _init_state = allocated;
2869
2870 { // Otherwise this needs to take out the Compile_lock.
2871 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2872 init_implementor();
2873 }
2874
2875 // Call remove_unshareable_info() on other objects that belong to this class, except
2876 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2877 // ArchiveBuilder::make_klasses_shareable(),
2878
2879 for (int i = 0; i < methods()->length(); i++) {
2880 Method* m = methods()->at(i);
2881 m->remove_unshareable_info();
2882 }
2883
2884 // do array classes also.
2885 if (array_klasses() != nullptr) {
2886 array_klasses()->remove_unshareable_info();
2887 }
2888
2889 // These are not allocated from metaspace. They are safe to set to nullptr.
2890 _source_debug_extension = nullptr;
2891 _dep_context = nullptr;
2892 _osr_nmethods_head = nullptr;
2893 #if INCLUDE_JVMTI
2894 _breakpoints = nullptr;
2895 _previous_versions = nullptr;
2896 _cached_class_file = nullptr;
2897 _jvmti_cached_class_field_map = nullptr;
2898 #endif
2899
2900 _init_thread = nullptr;
2901 _methods_jmethod_ids = nullptr;
2902 _jni_ids = nullptr;
2903 _oop_map_cache = nullptr;
2904 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2905 // keep _nest_host
2906 } else {
2907 // clear _nest_host to ensure re-load at runtime
2908 _nest_host = nullptr;
2909 }
2910 init_shared_package_entry();
2911 _dep_context_last_cleaned = 0;
2912 DEBUG_ONLY(_shared_class_load_count = 0);
2913
2914 remove_unshareable_flags();
2915 }
2916
2917 void InstanceKlass::remove_unshareable_flags() {
2918 // clear all the flags/stats that shouldn't be in the archived version
2919 assert(!is_scratch_class(), "must be");
2920 assert(!has_been_redefined(), "must be");
2921 #if INCLUDE_JVMTI
2922 set_is_being_redefined(false);
2923 #endif
2924 set_has_resolved_methods(false);
2925 }
2926
2927 void InstanceKlass::remove_java_mirror() {
2928 Klass::remove_java_mirror();
2929
2930 // do array classes also.
2931 if (array_klasses() != nullptr) {
2932 array_klasses()->remove_java_mirror();
2933 }
2934 }
2935
2936 void InstanceKlass::init_shared_package_entry() {
2937 assert(CDSConfig::is_dumping_archive(), "must be");
2938 #if !INCLUDE_CDS_JAVA_HEAP
2939 _package_entry = nullptr;
2940 #else
2941 if (CDSConfig::is_dumping_full_module_graph()) {
2942 if (is_shared_unregistered_class()) {
2943 _package_entry = nullptr;
2944 } else {
2945 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2946 }
2947 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2948 CDSConfig::is_using_full_module_graph() &&
2949 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2950 // _package_entry is an archived package in the base archive. Leave it as is.
2951 } else {
2952 _package_entry = nullptr;
2953 }
2954 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2955 #endif
2956 }
2957
2958 void InstanceKlass::compute_has_loops_flag_for_methods() {
2959 Array<Method*>* methods = this->methods();
2960 for (int index = 0; index < methods->length(); ++index) {
2961 Method* m = methods->at(index);
2962 if (!m->is_overpass()) { // work around JDK-8305771
2963 m->compute_has_loops_flag();
2964 }
2965 }
2966 }
2967
2968 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2969 PackageEntry* pkg_entry, TRAPS) {
2970 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2971 // before the InstanceKlass is added to the SystemDictionary. Make
2972 // sure the current state is <loaded.
2973 assert(!is_loaded(), "invalid init state");
2974 assert(!shared_loading_failed(), "Must not try to load failed class again");
2975 set_package(loader_data, pkg_entry, CHECK);
2976 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2977
2978 if (is_inline_klass()) {
2979 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2980 }
2981
2982 Array<Method*>* methods = this->methods();
2983 int num_methods = methods->length();
2984 for (int index = 0; index < num_methods; ++index) {
2985 methods->at(index)->restore_unshareable_info(CHECK);
2986 }
2987 #if INCLUDE_JVMTI
2988 if (JvmtiExport::has_redefined_a_class()) {
2989 // Reinitialize vtable because RedefineClasses may have changed some
2990 // entries in this vtable for super classes so the CDS vtable might
2991 // point to old or obsolete entries. RedefineClasses doesn't fix up
2992 // vtables in the shared system dictionary, only the main one.
2993 // It also redefines the itable too so fix that too.
2994 // First fix any default methods that point to a super class that may
2995 // have been redefined.
2996 bool trace_name_printed = false;
2997 adjust_default_methods(&trace_name_printed);
2998 if (verified_at_dump_time()) {
2999 // Initialize vtable and itable for classes which can be verified at dump time.
3000 // Unlinked classes such as old classes with major version < 50 cannot be verified
3001 // at dump time.
3002 vtable().initialize_vtable();
3003 itable().initialize_itable();
3004 }
3005 }
3006 #endif // INCLUDE_JVMTI
3007
3008 // restore constant pool resolved references
3009 constants()->restore_unshareable_info(CHECK);
3010
3011 if (array_klasses() != nullptr) {
3012 // To get a consistent list of classes we need MultiArray_lock to ensure
3013 // array classes aren't observed while they are being restored.
3014 RecursiveLocker rl(MultiArray_lock, THREAD);
3015 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
3016 // Array classes have null protection domain.
3017 // --> see ArrayKlass::complete_create_array_klass()
3018 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3019 }
3020
3021 // Initialize @ValueBased class annotation if not already set in the archived klass.
3022 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
3023 set_is_value_based();
3024 }
3025 }
3026
3027 // Check if a class or any of its supertypes has a version older than 50.
3028 // CDS will not perform verification of old classes during dump time because
3029 // without changing the old verifier, the verification constraint cannot be
3030 // retrieved during dump time.
3031 // Verification of archived old classes will be performed during run time.
3032 bool InstanceKlass::can_be_verified_at_dumptime() const {
3033 if (MetaspaceShared::is_in_shared_metaspace(this)) {
3034 // This is a class that was dumped into the base archive, so we know
3035 // it was verified at dump time.
3036 return true;
3037 }
3038 if (major_version() < 50 /*JAVA_6_VERSION*/) {
3039 return false;
3040 }
3041 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
3042 return false;
3043 }
3044 Array<InstanceKlass*>* interfaces = local_interfaces();
3045 int len = interfaces->length();
3046 for (int i = 0; i < len; i++) {
3047 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3048 return false;
3049 }
3050 }
3051 return true;
3052 }
3053
3054 int InstanceKlass::shared_class_loader_type() const {
3055 if (is_shared_boot_class()) {
3056 return ClassLoader::BOOT_LOADER;
3057 } else if (is_shared_platform_class()) {
3058 return ClassLoader::PLATFORM_LOADER;
3059 } else if (is_shared_app_class()) {
3060 return ClassLoader::APP_LOADER;
3061 } else {
3062 return ClassLoader::OTHER;
3063 }
3064 }
3065 #endif // INCLUDE_CDS
3066
3067 #if INCLUDE_JVMTI
3068 static void clear_all_breakpoints(Method* m) {
3069 m->clear_all_breakpoints();
3070 }
3071 #endif
3072
3073 void InstanceKlass::unload_class(InstanceKlass* ik) {
3074
3075 if (ik->is_scratch_class()) {
3076 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
3077 return;
3078 }
3079 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
3080
3081 // Release dependencies.
3082 ik->dependencies().remove_all_dependents();
3083
3084 // notify the debugger
3085 if (JvmtiExport::should_post_class_unload()) {
3086 JvmtiExport::post_class_unload(ik);
3087 }
3088
3089 // notify ClassLoadingService of class unload
3090 ClassLoadingService::notify_class_unloaded(ik);
3091
3092 SystemDictionaryShared::handle_class_unloading(ik);
3093
3094 if (log_is_enabled(Info, class, unload)) {
3095 ResourceMark rm;
3096 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3097 }
3098
3099 Events::log_class_unloading(Thread::current(), ik);
3100
3101 #if INCLUDE_JFR
3102 assert(ik != nullptr, "invariant");
3103 EventClassUnload event;
3104 event.set_unloadedClass(ik);
3105 event.set_definingClassLoader(ik->class_loader_data());
3106 event.commit();
3107 #endif
3108 }
3109
3110 static void method_release_C_heap_structures(Method* m) {
3111 m->release_C_heap_structures();
3112 }
3113
3114 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3115 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3116 // Clean up C heap
3117 Klass::release_C_heap_structures();
3118
3119 // Deallocate and call destructors for MDO mutexes
3120 if (release_sub_metadata) {
3121 methods_do(method_release_C_heap_structures);
3122 }
3123
3124 // Deallocate oop map cache
3125 if (_oop_map_cache != nullptr) {
3126 delete _oop_map_cache;
3127 _oop_map_cache = nullptr;
3128 }
3129
3130 // Deallocate JNI identifiers for jfieldIDs
3131 JNIid::deallocate(jni_ids());
3132 set_jni_ids(nullptr);
3133
3134 jmethodID* jmeths = methods_jmethod_ids_acquire();
3135 if (jmeths != nullptr) {
3136 release_set_methods_jmethod_ids(nullptr);
3137 FreeHeap(jmeths);
3138 }
3139
3140 assert(_dep_context == nullptr,
3141 "dependencies should already be cleaned");
3142
3143 #if INCLUDE_JVMTI
3144 // Deallocate breakpoint records
3145 if (breakpoints() != nullptr) {
3146 methods_do(clear_all_breakpoints);
3147 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3148 }
3149
3150 // deallocate the cached class file
3151 if (_cached_class_file != nullptr) {
3152 os::free(_cached_class_file);
3153 _cached_class_file = nullptr;
3154 }
3155 #endif
3156
3157 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3158
3159 if (release_sub_metadata) {
3160 constants()->release_C_heap_structures();
3161 }
3162 }
3163
3164 // The constant pool is on stack if any of the methods are executing or
3165 // referenced by handles.
3166 bool InstanceKlass::on_stack() const {
3167 return _constants->on_stack();
3168 }
3169
3170 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3171 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3172 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3173
3174 // minor and major version numbers of class file
3175 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3176 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3177 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3178 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3179
3180 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3181 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3182 if (ik->constants()->version() == version) {
3183 return ik;
3184 }
3185 }
3186 return nullptr;
3187 }
3188
3189 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3190 if (array == nullptr) {
3191 _source_debug_extension = nullptr;
3192 } else {
3193 // Adding one to the attribute length in order to store a null terminator
3194 // character could cause an overflow because the attribute length is
3195 // already coded with an u4 in the classfile, but in practice, it's
3196 // unlikely to happen.
3197 assert((length+1) > length, "Overflow checking");
3198 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3199 for (int i = 0; i < length; i++) {
3200 sde[i] = array[i];
3201 }
3202 sde[length] = '\0';
3203 _source_debug_extension = sde;
3204 }
3205 }
3206
3207 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3208 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3209 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3210
3211 const char* InstanceKlass::signature_name() const {
3212 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3213 }
3214
3215 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3216 // Get the internal name as a c string
3217 const char* src = (const char*) (name()->as_C_string());
3218 const int src_length = (int)strlen(src);
3219
3220 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3221
3222 // Add L or Q as type indicator
3223 int dest_index = 0;
3224 dest[dest_index++] = c;
3225
3226 // Add the actual class name
3227 for (int src_index = 0; src_index < src_length; ) {
3228 dest[dest_index++] = src[src_index++];
3229 }
3230
3231 if (is_hidden()) { // Replace the last '+' with a '.'.
3232 for (int index = (int)src_length; index > 0; index--) {
3233 if (dest[index] == '+') {
3234 dest[index] = JVM_SIGNATURE_DOT;
3235 break;
3236 }
3237 }
3238 }
3239
3240 // Add the semicolon and the null
3241 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3242 dest[dest_index] = '\0';
3243 return dest;
3244 }
3245
3246 ModuleEntry* InstanceKlass::module() const {
3247 if (is_hidden() &&
3248 in_unnamed_package() &&
3249 class_loader_data()->has_class_mirror_holder()) {
3250 // For a non-strong hidden class defined to an unnamed package,
3251 // its (class held) CLD will not have an unnamed module created for it.
3252 // Two choices to find the correct ModuleEntry:
3253 // 1. If hidden class is within a nest, use nest host's module
3254 // 2. Find the unnamed module off from the class loader
3255 // For now option #2 is used since a nest host is not set until
3256 // after the instance class is created in jvm_lookup_define_class().
3257 if (class_loader_data()->is_boot_class_loader_data()) {
3258 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3259 } else {
3260 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3261 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3262 return java_lang_Module::module_entry(module);
3263 }
3264 }
3265
3266 // Class is in a named package
3267 if (!in_unnamed_package()) {
3268 return _package_entry->module();
3269 }
3270
3271 // Class is in an unnamed package, return its loader's unnamed module
3272 return class_loader_data()->unnamed_module();
3273 }
3274
3275 bool InstanceKlass::in_javabase_module() const {
3276 return module()->name() == vmSymbols::java_base();
3277 }
3278
3279 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3280
3281 // ensure java/ packages only loaded by boot or platform builtin loaders
3282 // not needed for shared class since CDS does not archive prohibited classes.
3283 if (!is_shared()) {
3284 check_prohibited_package(name(), loader_data, CHECK);
3285 }
3286
3287 if (is_shared() && _package_entry != nullptr) {
3288 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3289 // we can use the saved package
3290 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3291 return;
3292 } else {
3293 _package_entry = nullptr;
3294 }
3295 }
3296
3297 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3298 // it returns, so we need to decrement it when the current function exits.
3299 TempNewSymbol from_class_name =
3300 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3301
3302 Symbol* pkg_name;
3303 if (pkg_entry != nullptr) {
3304 pkg_name = pkg_entry->name();
3305 } else {
3306 pkg_name = from_class_name;
3307 }
3308
3309 if (pkg_name != nullptr && loader_data != nullptr) {
3310
3311 // Find in class loader's package entry table.
3312 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3313
3314 // If the package name is not found in the loader's package
3315 // entry table, it is an indication that the package has not
3316 // been defined. Consider it defined within the unnamed module.
3317 if (_package_entry == nullptr) {
3318
3319 if (!ModuleEntryTable::javabase_defined()) {
3320 // Before java.base is defined during bootstrapping, define all packages in
3321 // the java.base module. If a non-java.base package is erroneously placed
3322 // in the java.base module it will be caught later when java.base
3323 // is defined by ModuleEntryTable::verify_javabase_packages check.
3324 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3325 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3326 } else {
3327 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3328 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3329 }
3330
3331 // A package should have been successfully created
3332 DEBUG_ONLY(ResourceMark rm(THREAD));
3333 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3334 name()->as_C_string(), loader_data->loader_name_and_id());
3335 }
3336
3337 if (log_is_enabled(Debug, module)) {
3338 ResourceMark rm(THREAD);
3339 ModuleEntry* m = _package_entry->module();
3340 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3341 external_name(),
3342 pkg_name->as_C_string(),
3343 loader_data->loader_name_and_id(),
3344 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3345 }
3346 } else {
3347 ResourceMark rm(THREAD);
3348 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3349 external_name(),
3350 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3351 UNNAMED_MODULE);
3352 }
3353 }
3354
3355 // Function set_classpath_index ensures that for a non-null _package_entry
3356 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3357 // It then sets the classpath_index in the package entry record.
3358 //
3359 // The classpath_index field is used to find the entry on the boot loader class
3360 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3361 // in an unnamed module. It is also used to indicate (for all packages whose
3362 // classes are loaded by the boot loader) that at least one of the package's
3363 // classes has been loaded.
3364 void InstanceKlass::set_classpath_index(s2 path_index) {
3365 if (_package_entry != nullptr) {
3366 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3367 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3368 assert(path_index != -1, "Unexpected classpath_index");
3369 _package_entry->set_classpath_index(path_index);
3370 }
3371 }
3372
3373 // different versions of is_same_class_package
3374
3375 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3376 oop classloader1 = this->class_loader();
3377 PackageEntry* classpkg1 = this->package();
3378 if (class2->is_objArray_klass()) {
3379 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3380 }
3381
3382 oop classloader2;
3383 PackageEntry* classpkg2;
3384 if (class2->is_instance_klass()) {
3385 classloader2 = class2->class_loader();
3386 classpkg2 = class2->package();
3387 } else {
3388 assert(class2->is_typeArray_klass(), "should be type array");
3389 classloader2 = nullptr;
3390 classpkg2 = nullptr;
3391 }
3392
3393 // Same package is determined by comparing class loader
3394 // and package entries. Both must be the same. This rule
3395 // applies even to classes that are defined in the unnamed
3396 // package, they still must have the same class loader.
3397 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3398 return true;
3399 }
3400
3401 return false;
3402 }
3403
3404 // return true if this class and other_class are in the same package. Classloader
3405 // and classname information is enough to determine a class's package
3406 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3407 const Symbol* other_class_name) const {
3408 if (class_loader() != other_class_loader) {
3409 return false;
3410 }
3411 if (name()->fast_compare(other_class_name) == 0) {
3412 return true;
3413 }
3414
3415 {
3416 ResourceMark rm;
3417
3418 bool bad_class_name = false;
3419 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3420 if (bad_class_name) {
3421 return false;
3422 }
3423 // Check that package_from_class_name() returns null, not "", if there is no package.
3424 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3425
3426 const Symbol* const this_package_name =
3427 this->package() != nullptr ? this->package()->name() : nullptr;
3428
3429 if (this_package_name == nullptr || other_pkg == nullptr) {
3430 // One of the two doesn't have a package. Only return true if the other
3431 // one also doesn't have a package.
3432 return this_package_name == other_pkg;
3433 }
3434
3435 // Check if package is identical
3436 return this_package_name->fast_compare(other_pkg) == 0;
3437 }
3438 }
3439
3440 static bool is_prohibited_package_slow(Symbol* class_name) {
3441 // Caller has ResourceMark
3442 int length;
3443 jchar* unicode = class_name->as_unicode(length);
3444 return (length >= 5 &&
3445 unicode[0] == 'j' &&
3446 unicode[1] == 'a' &&
3447 unicode[2] == 'v' &&
3448 unicode[3] == 'a' &&
3449 unicode[4] == '/');
3450 }
3451
3452 // Only boot and platform class loaders can define classes in "java/" packages.
3453 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3454 ClassLoaderData* loader_data,
3455 TRAPS) {
3456 if (!loader_data->is_boot_class_loader_data() &&
3457 !loader_data->is_platform_class_loader_data() &&
3458 class_name != nullptr && class_name->utf8_length() >= 5) {
3459 ResourceMark rm(THREAD);
3460 bool prohibited;
3461 const u1* base = class_name->base();
3462 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3463 prohibited = is_prohibited_package_slow(class_name);
3464 } else {
3465 char* name = class_name->as_C_string();
3466 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3467 }
3468 if (prohibited) {
3469 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3470 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3471 char* name = pkg_name->as_C_string();
3472 const char* class_loader_name = loader_data->loader_name_and_id();
3473 StringUtils::replace_no_expand(name, "/", ".");
3474 const char* msg_text1 = "Class loader (instance of): ";
3475 const char* msg_text2 = " tried to load prohibited package name: ";
3476 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3477 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3478 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3479 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3480 }
3481 }
3482 return;
3483 }
3484
3485 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3486 constantPoolHandle i_cp(THREAD, constants());
3487 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3488 int ioff = iter.inner_class_info_index();
3489 if (ioff != 0) {
3490 // Check to see if the name matches the class we're looking for
3491 // before attempting to find the class.
3492 if (i_cp->klass_name_at_matches(this, ioff)) {
3493 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3494 if (this == inner_klass) {
3495 *ooff = iter.outer_class_info_index();
3496 *noff = iter.inner_name_index();
3497 return true;
3498 }
3499 }
3500 }
3501 }
3502 return false;
3503 }
3504
3505 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3506 InstanceKlass* outer_klass = nullptr;
3507 *inner_is_member = false;
3508 int ooff = 0, noff = 0;
3509 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3510 if (has_inner_classes_attr) {
3511 constantPoolHandle i_cp(THREAD, constants());
3512 if (ooff != 0) {
3513 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3514 if (!ok->is_instance_klass()) {
3515 // If the outer class is not an instance klass then it cannot have
3516 // declared any inner classes.
3517 ResourceMark rm(THREAD);
3518 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3519 Exceptions::fthrow(
3520 THREAD_AND_LOCATION,
3521 vmSymbols::java_lang_IncompatibleClassChangeError(),
3522 "%s and %s disagree on InnerClasses attribute",
3523 ok->external_name(),
3524 external_name());
3525 return nullptr;
3526 }
3527 outer_klass = InstanceKlass::cast(ok);
3528 *inner_is_member = true;
3529 }
3530 if (nullptr == outer_klass) {
3531 // It may be a local class; try for that.
3532 int encl_method_class_idx = enclosing_method_class_index();
3533 if (encl_method_class_idx != 0) {
3534 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3535 outer_klass = InstanceKlass::cast(ok);
3536 *inner_is_member = false;
3537 }
3538 }
3539 }
3540
3541 // If no inner class attribute found for this class.
3542 if (nullptr == outer_klass) return nullptr;
3543
3544 // Throws an exception if outer klass has not declared k as an inner klass
3545 // We need evidence that each klass knows about the other, or else
3546 // the system could allow a spoof of an inner class to gain access rights.
3547 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3548 return outer_klass;
3549 }
3550
3551 u2 InstanceKlass::compute_modifier_flags() const {
3552 u2 access = access_flags().as_unsigned_short();
3553
3554 // But check if it happens to be member class.
3555 InnerClassesIterator iter(this);
3556 for (; !iter.done(); iter.next()) {
3557 int ioff = iter.inner_class_info_index();
3558 // Inner class attribute can be zero, skip it.
3559 // Strange but true: JVM spec. allows null inner class refs.
3560 if (ioff == 0) continue;
3561
3562 // only look at classes that are already loaded
3563 // since we are looking for the flags for our self.
3564 Symbol* inner_name = constants()->klass_name_at(ioff);
3565 if (name() == inner_name) {
3566 // This is really a member class.
3567 access = iter.inner_access_flags();
3568 break;
3569 }
3570 }
3571 return access;
3572 }
3573
3574 jint InstanceKlass::jvmti_class_status() const {
3575 jint result = 0;
3576
3577 if (is_linked()) {
3578 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3579 }
3580
3581 if (is_initialized()) {
3582 assert(is_linked(), "Class status is not consistent");
3583 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3584 }
3585 if (is_in_error_state()) {
3586 result |= JVMTI_CLASS_STATUS_ERROR;
3587 }
3588 return result;
3589 }
3590
3591 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3592 bool implements_interface; // initialized by method_at_itable_or_null
3593 Method* m = method_at_itable_or_null(holder, index,
3594 implements_interface); // out parameter
3595 if (m != nullptr) {
3596 assert(implements_interface, "sanity");
3597 return m;
3598 } else if (implements_interface) {
3599 // Throw AbstractMethodError since corresponding itable slot is empty.
3600 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3601 } else {
3602 // If the interface isn't implemented by the receiver class,
3603 // the VM should throw IncompatibleClassChangeError.
3604 ResourceMark rm(THREAD);
3605 stringStream ss;
3606 bool same_module = (module() == holder->module());
3607 ss.print("Receiver class %s does not implement "
3608 "the interface %s defining the method to be called "
3609 "(%s%s%s)",
3610 external_name(), holder->external_name(),
3611 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3612 (same_module) ? "" : "; ",
3613 (same_module) ? "" : holder->class_in_module_of_loader());
3614 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3615 }
3616 }
3617
3618 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3619 klassItable itable(this);
3620 for (int i = 0; i < itable.size_offset_table(); i++) {
3621 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3622 if (offset_entry->interface_klass() == holder) {
3623 implements_interface = true;
3624 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3625 Method* m = ime[index].method();
3626 return m;
3627 }
3628 }
3629 implements_interface = false;
3630 return nullptr; // offset entry not found
3631 }
3632
3633 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3634 assert(is_linked(), "required");
3635 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3636 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3637
3638 int vtable_index = Method::invalid_vtable_index;
3639 Symbol* name = intf_method->name();
3640 Symbol* signature = intf_method->signature();
3641
3642 // First check in default method array
3643 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3644 int index = find_method_index(default_methods(),
3645 name, signature,
3646 Klass::OverpassLookupMode::find,
3647 Klass::StaticLookupMode::find,
3648 Klass::PrivateLookupMode::find);
3649 if (index >= 0) {
3650 vtable_index = default_vtable_indices()->at(index);
3651 }
3652 }
3653 if (vtable_index == Method::invalid_vtable_index) {
3654 // get vtable_index for miranda methods
3655 klassVtable vt = vtable();
3656 vtable_index = vt.index_of_miranda(name, signature);
3657 }
3658 return vtable_index;
3659 }
3660
3661 #if INCLUDE_JVMTI
3662 // update default_methods for redefineclasses for methods that are
3663 // not yet in the vtable due to concurrent subclass define and superinterface
3664 // redefinition
3665 // Note: those in the vtable, should have been updated via adjust_method_entries
3666 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3667 // search the default_methods for uses of either obsolete or EMCP methods
3668 if (default_methods() != nullptr) {
3669 for (int index = 0; index < default_methods()->length(); index ++) {
3670 Method* old_method = default_methods()->at(index);
3671 if (old_method == nullptr || !old_method->is_old()) {
3672 continue; // skip uninteresting entries
3673 }
3674 assert(!old_method->is_deleted(), "default methods may not be deleted");
3675 Method* new_method = old_method->get_new_method();
3676 default_methods()->at_put(index, new_method);
3677
3678 if (log_is_enabled(Info, redefine, class, update)) {
3679 ResourceMark rm;
3680 if (!(*trace_name_printed)) {
3681 log_info(redefine, class, update)
3682 ("adjust: klassname=%s default methods from name=%s",
3683 external_name(), old_method->method_holder()->external_name());
3684 *trace_name_printed = true;
3685 }
3686 log_debug(redefine, class, update, vtables)
3687 ("default method update: %s(%s) ",
3688 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3689 }
3690 }
3691 }
3692 }
3693 #endif // INCLUDE_JVMTI
3694
3695 // On-stack replacement stuff
3696 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3697 assert_lock_strong(NMethodState_lock);
3698 #ifndef PRODUCT
3699 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3700 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3701 "redundant OSR recompilation detected. memory leak in CodeCache!");
3702 #endif
3703 // only one compilation can be active
3704 assert(n->is_osr_method(), "wrong kind of nmethod");
3705 n->set_osr_link(osr_nmethods_head());
3706 set_osr_nmethods_head(n);
3707 // Raise the highest osr level if necessary
3708 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3709
3710 // Get rid of the osr methods for the same bci that have lower levels.
3711 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3712 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3713 if (inv != nullptr && inv->is_in_use()) {
3714 inv->make_not_entrant("OSR invalidation of lower levels");
3715 }
3716 }
3717 }
3718
3719 // Remove osr nmethod from the list. Return true if found and removed.
3720 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3721 // This is a short non-blocking critical region, so the no safepoint check is ok.
3722 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3723 assert(n->is_osr_method(), "wrong kind of nmethod");
3724 nmethod* last = nullptr;
3725 nmethod* cur = osr_nmethods_head();
3726 int max_level = CompLevel_none; // Find the max comp level excluding n
3727 Method* m = n->method();
3728 // Search for match
3729 bool found = false;
3730 while(cur != nullptr && cur != n) {
3731 if (m == cur->method()) {
3732 // Find max level before n
3733 max_level = MAX2(max_level, cur->comp_level());
3734 }
3735 last = cur;
3736 cur = cur->osr_link();
3737 }
3738 nmethod* next = nullptr;
3739 if (cur == n) {
3740 found = true;
3741 next = cur->osr_link();
3742 if (last == nullptr) {
3743 // Remove first element
3744 set_osr_nmethods_head(next);
3745 } else {
3746 last->set_osr_link(next);
3747 }
3748 }
3749 n->set_osr_link(nullptr);
3750 cur = next;
3751 while (cur != nullptr) {
3752 // Find max level after n
3753 if (m == cur->method()) {
3754 max_level = MAX2(max_level, cur->comp_level());
3755 }
3756 cur = cur->osr_link();
3757 }
3758 m->set_highest_osr_comp_level(max_level);
3759 return found;
3760 }
3761
3762 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3763 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3764 nmethod* osr = osr_nmethods_head();
3765 int found = 0;
3766 while (osr != nullptr) {
3767 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3768 if (osr->method() == m) {
3769 deopt_scope->mark(osr);
3770 found++;
3771 }
3772 osr = osr->osr_link();
3773 }
3774 return found;
3775 }
3776
3777 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3778 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3779 nmethod* osr = osr_nmethods_head();
3780 nmethod* best = nullptr;
3781 while (osr != nullptr) {
3782 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3783 // There can be a time when a c1 osr method exists but we are waiting
3784 // for a c2 version. When c2 completes its osr nmethod we will trash
3785 // the c1 version and only be able to find the c2 version. However
3786 // while we overflow in the c1 code at back branches we don't want to
3787 // try and switch to the same code as we are already running
3788
3789 if (osr->method() == m &&
3790 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3791 if (match_level) {
3792 if (osr->comp_level() == comp_level) {
3793 // Found a match - return it.
3794 return osr;
3795 }
3796 } else {
3797 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3798 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3799 // Found the best possible - return it.
3800 return osr;
3801 }
3802 best = osr;
3803 }
3804 }
3805 }
3806 osr = osr->osr_link();
3807 }
3808
3809 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3810 if (best != nullptr && best->comp_level() >= comp_level) {
3811 return best;
3812 }
3813 return nullptr;
3814 }
3815
3816 // -----------------------------------------------------------------------------------------------------
3817 // Printing
3818
3819 #define BULLET " - "
3820
3821 static const char* state_names[] = {
3822 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3823 };
3824
3825 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3826 ResourceMark rm;
3827 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3828 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3829 for (int i = 0; i < len; i++) {
3830 intptr_t e = start[i];
3831 st->print("%d : " INTPTR_FORMAT, i, e);
3832 if (forward_refs[i] != 0) {
3833 int from = forward_refs[i];
3834 int off = (int) start[from];
3835 st->print(" (offset %d <= [%d])", off, from);
3836 }
3837 if (MetaspaceObj::is_valid((Metadata*)e)) {
3838 st->print(" ");
3839 ((Metadata*)e)->print_value_on(st);
3840 } else if (self != nullptr && e > 0 && e < 0x10000) {
3841 address location = self + e;
3842 int index = (int)((intptr_t*)location - start);
3843 st->print(" (offset %d => [%d])", (int)e, index);
3844 if (index >= 0 && index < len)
3845 forward_refs[index] = i;
3846 }
3847 st->cr();
3848 }
3849 }
3850
3851 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3852 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3853 }
3854
3855 template<typename T>
3856 static void print_array_on(outputStream* st, Array<T>* array) {
3857 if (array == nullptr) { st->print_cr("nullptr"); return; }
3858 array->print_value_on(st); st->cr();
3859 if (Verbose || WizardMode) {
3860 for (int i = 0; i < array->length(); i++) {
3861 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3862 }
3863 }
3864 }
3865
3866 static void print_array_on(outputStream* st, Array<int>* array) {
3867 if (array == nullptr) { st->print_cr("nullptr"); return; }
3868 array->print_value_on(st); st->cr();
3869 if (Verbose || WizardMode) {
3870 for (int i = 0; i < array->length(); i++) {
3871 st->print("%d : %d", i, array->at(i)); st->cr();
3872 }
3873 }
3874 }
3875
3876 const char* InstanceKlass::init_state_name() const {
3877 return state_names[init_state()];
3878 }
3879
3880 void InstanceKlass::print_on(outputStream* st) const {
3881 assert(is_klass(), "must be klass");
3882 Klass::print_on(st);
3883
3884 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3885 st->print(BULLET"klass size: %d", size()); st->cr();
3886 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3887 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3888 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3889 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3890 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3891 st->print(BULLET"sub: ");
3892 Klass* sub = subklass();
3893 int n;
3894 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3895 if (n < MaxSubklassPrintSize) {
3896 sub->print_value_on(st);
3897 st->print(" ");
3898 }
3899 }
3900 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3901 st->cr();
3902
3903 if (is_interface()) {
3904 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3905 if (nof_implementors() == 1) {
3906 st->print_cr(BULLET"implementor: ");
3907 st->print(" ");
3908 implementor()->print_value_on(st);
3909 st->cr();
3910 }
3911 }
3912
3913 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3914 st->print(BULLET"methods: "); print_array_on(st, methods());
3915 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3916 if (default_methods() != nullptr) {
3917 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3918 }
3919 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3920 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3921 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3922
3923 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3924
3925 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3926 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3927
3928 if (secondary_supers() != nullptr) {
3929 if (Verbose) {
3930 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3931 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3932 for (int i = 0; i < _secondary_supers->length(); i++) {
3933 ResourceMark rm; // for external_name()
3934 Klass* secondary_super = _secondary_supers->at(i);
3935 st->print(BULLET"%2d:", i);
3936 if (is_hashed) {
3937 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3938 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3939 st->print(" dist:%02d:", distance);
3940 }
3941 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3942 }
3943 }
3944 }
3945 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3946
3947 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3948 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3949 if (source_debug_extension() != nullptr) {
3950 st->print(BULLET"source debug extension: ");
3951 st->print("%s", source_debug_extension());
3952 st->cr();
3953 }
3954 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3955 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3956 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3957 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3958 {
3959 bool have_pv = false;
3960 // previous versions are linked together through the InstanceKlass
3961 for (InstanceKlass* pv_node = previous_versions();
3962 pv_node != nullptr;
3963 pv_node = pv_node->previous_versions()) {
3964 if (!have_pv)
3965 st->print(BULLET"previous version: ");
3966 have_pv = true;
3967 pv_node->constants()->print_value_on(st);
3968 }
3969 if (have_pv) st->cr();
3970 }
3971
3972 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3973 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3974 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3975 print_on_maybe_null(st, BULLET"record components: ", record_components());
3976 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3977 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
3978 if (java_mirror() != nullptr) {
3979 st->print(BULLET"java mirror: ");
3980 java_mirror()->print_value_on(st);
3981 st->cr();
3982 } else {
3983 st->print_cr(BULLET"java mirror: null");
3984 }
3985 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3986 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3987 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3988 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3989 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3990
3991 FieldPrinter print_static_field(st);
3992 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3993 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3994 FieldPrinter print_nonstatic_field(st);
3995 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3996 ik->print_nonstatic_fields(&print_nonstatic_field);
3997
3998 st->print(BULLET"non-static oop maps: ");
3999 OopMapBlock* map = start_of_nonstatic_oop_maps();
4000 OopMapBlock* end_map = map + nonstatic_oop_map_count();
4001 while (map < end_map) {
4002 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
4003 map++;
4004 }
4005 st->cr();
4006 }
4007
4008 void InstanceKlass::print_value_on(outputStream* st) const {
4009 assert(is_klass(), "must be klass");
4010 if (Verbose || WizardMode) access_flags().print_on(st);
4011 name()->print_value_on(st);
4012 }
4013
4014 void FieldPrinter::do_field(fieldDescriptor* fd) {
4015 for (int i = 0; i < _indent; i++) _st->print(" ");
4016 _st->print(BULLET);
4017 if (_obj == nullptr) {
4018 fd->print_on(_st, _base_offset);
4019 _st->cr();
4020 } else {
4021 fd->print_on_for(_st, _obj, _indent, _base_offset);
4022 if (!fd->field_flags().is_flat()) _st->cr();
4023 }
4024 }
4025
4026
4027 void InstanceKlass::oop_print_on(oop obj, outputStream* st, int indent, int base_offset) {
4028 Klass::oop_print_on(obj, st);
4029
4030 if (this == vmClasses::String_klass()) {
4031 typeArrayOop value = java_lang_String::value(obj);
4032 juint length = java_lang_String::length(obj);
4033 if (value != nullptr &&
4034 value->is_typeArray() &&
4035 length <= (juint) value->length()) {
4036 st->print(BULLET"string: ");
4037 java_lang_String::print(obj, st);
4038 st->cr();
4039 }
4040 }
4041
4042 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
4043 FieldPrinter print_field(st, obj, indent, base_offset);
4044 print_nonstatic_fields(&print_field);
4045
4046 if (this == vmClasses::Class_klass()) {
4047 st->print(BULLET"signature: ");
4048 java_lang_Class::print_signature(obj, st);
4049 st->cr();
4050 Klass* real_klass = java_lang_Class::as_Klass(obj);
4051 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4052 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4053 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4054 }
4055 } else if (this == vmClasses::MethodType_klass()) {
4056 st->print(BULLET"signature: ");
4057 java_lang_invoke_MethodType::print_signature(obj, st);
4058 st->cr();
4059 }
4060 }
4061
4062 #ifndef PRODUCT
4063
4064 bool InstanceKlass::verify_itable_index(int i) {
4065 int method_count = klassItable::method_count_for_interface(this);
4066 assert(i >= 0 && i < method_count, "index out of bounds");
4067 return true;
4068 }
4069
4070 #endif //PRODUCT
4071
4072 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4073 st->print("a ");
4074 name()->print_value_on(st);
4075 obj->print_address_on(st);
4076 if (this == vmClasses::String_klass()
4077 && java_lang_String::value(obj) != nullptr) {
4078 ResourceMark rm;
4079 int len = java_lang_String::length(obj);
4080 int plen = (len < 24 ? len : 12);
4081 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4082 st->print(" = \"%s\"", str);
4083 if (len > plen)
4084 st->print("...[%d]", len);
4085 } else if (this == vmClasses::Class_klass()) {
4086 Klass* k = java_lang_Class::as_Klass(obj);
4087 st->print(" = ");
4088 if (k != nullptr) {
4089 k->print_value_on(st);
4090 } else {
4091 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4092 st->print("%s", tname ? tname : "type?");
4093 }
4094 } else if (this == vmClasses::MethodType_klass()) {
4095 st->print(" = ");
4096 java_lang_invoke_MethodType::print_signature(obj, st);
4097 } else if (java_lang_boxing_object::is_instance(obj)) {
4098 st->print(" = ");
4099 java_lang_boxing_object::print(obj, st);
4100 } else if (this == vmClasses::LambdaForm_klass()) {
4101 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4102 if (vmentry != nullptr) {
4103 st->print(" => ");
4104 vmentry->print_value_on(st);
4105 }
4106 } else if (this == vmClasses::MemberName_klass()) {
4107 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4108 if (vmtarget != nullptr) {
4109 st->print(" = ");
4110 vmtarget->print_value_on(st);
4111 } else {
4112 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4113 oop name = java_lang_invoke_MemberName::name(obj);
4114 if (clazz != nullptr) {
4115 clazz->print_value_on(st);
4116 } else {
4117 st->print("null");
4118 }
4119 st->print(".");
4120 if (name != nullptr) {
4121 name->print_value_on(st);
4122 } else {
4123 st->print("null");
4124 }
4125 }
4126 }
4127 }
4128
4129 const char* InstanceKlass::internal_name() const {
4130 return external_name();
4131 }
4132
4133 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4134 const ModuleEntry* module_entry,
4135 const ClassFileStream* cfs) const {
4136
4137 if (ClassListWriter::is_enabled()) {
4138 ClassListWriter::write(this, cfs);
4139 }
4140
4141 print_class_load_helper(loader_data, module_entry, cfs);
4142 print_class_load_cause_logging();
4143 }
4144
4145 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4146 const ModuleEntry* module_entry,
4147 const ClassFileStream* cfs) const {
4148
4149 if (!log_is_enabled(Info, class, load)) {
4150 return;
4151 }
4152
4153 ResourceMark rm;
4154 LogMessage(class, load) msg;
4155 stringStream info_stream;
4156
4157 // Name and class hierarchy info
4158 info_stream.print("%s", external_name());
4159
4160 // Source
4161 if (cfs != nullptr) {
4162 if (cfs->source() != nullptr) {
4163 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4164 if (module_name != nullptr) {
4165 // When the boot loader created the stream, it didn't know the module name
4166 // yet. Let's format it now.
4167 if (cfs->from_boot_loader_modules_image()) {
4168 info_stream.print(" source: jrt:/%s", module_name);
4169 } else {
4170 info_stream.print(" source: %s", cfs->source());
4171 }
4172 } else {
4173 info_stream.print(" source: %s", cfs->source());
4174 }
4175 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4176 Thread* current = Thread::current();
4177 Klass* caller = current->is_Java_thread() ?
4178 JavaThread::cast(current)->security_get_caller_class(1):
4179 nullptr;
4180 // caller can be null, for example, during a JVMTI VM_Init hook
4181 if (caller != nullptr) {
4182 info_stream.print(" source: instance of %s", caller->external_name());
4183 } else {
4184 // source is unknown
4185 }
4186 } else {
4187 oop class_loader = loader_data->class_loader();
4188 info_stream.print(" source: %s", class_loader->klass()->external_name());
4189 }
4190 } else {
4191 assert(this->is_shared(), "must be");
4192 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4193 info_stream.print(" source: shared objects file (top)");
4194 } else {
4195 info_stream.print(" source: shared objects file");
4196 }
4197 }
4198
4199 msg.info("%s", info_stream.as_string());
4200
4201 if (log_is_enabled(Debug, class, load)) {
4202 stringStream debug_stream;
4203
4204 // Class hierarchy info
4205 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4206 p2i(this), p2i(superklass()));
4207
4208 // Interfaces
4209 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4210 debug_stream.print(" interfaces:");
4211 int length = local_interfaces()->length();
4212 for (int i = 0; i < length; i++) {
4213 debug_stream.print(" " PTR_FORMAT,
4214 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4215 }
4216 }
4217
4218 // Class loader
4219 debug_stream.print(" loader: [");
4220 loader_data->print_value_on(&debug_stream);
4221 debug_stream.print("]");
4222
4223 // Classfile checksum
4224 if (cfs) {
4225 debug_stream.print(" bytes: %d checksum: %08x",
4226 cfs->length(),
4227 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4228 cfs->length()));
4229 }
4230
4231 msg.debug("%s", debug_stream.as_string());
4232 }
4233 }
4234
4235 void InstanceKlass::print_class_load_cause_logging() const {
4236 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4237 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4238 JavaThread* current = JavaThread::current();
4239 ResourceMark rm(current);
4240 const char* name = external_name();
4241
4242 if (LogClassLoadingCauseFor == nullptr ||
4243 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4244 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4245 return;
4246 }
4247
4248 // Log Java stack first
4249 {
4250 LogMessage(class, load, cause) msg;
4251 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4252
4253 info_stream.print_cr("Java stack when loading %s:", name);
4254 current->print_stack_on(&info_stream);
4255 }
4256
4257 // Log native stack second
4258 if (log_cause_native) {
4259 // Log to string first so that lines can be indented
4260 stringStream stack_stream;
4261 char buf[O_BUFLEN];
4262 address lastpc = nullptr;
4263 NativeStackPrinter nsp(current);
4264 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4265 true /* print_source_info */, -1 /* max stack */);
4266
4267 LogMessage(class, load, cause, native) msg;
4268 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4269 info_stream.print_cr("Native stack when loading %s:", name);
4270
4271 // Print each native stack line to the log
4272 int size = (int) stack_stream.size();
4273 char* stack = stack_stream.as_string();
4274 char* stack_end = stack + size;
4275 char* line_start = stack;
4276 for (char* p = stack; p < stack_end; p++) {
4277 if (*p == '\n') {
4278 *p = '\0';
4279 info_stream.print_cr("\t%s", line_start);
4280 line_start = p + 1;
4281 }
4282 }
4283 if (line_start < stack_end) {
4284 info_stream.print_cr("\t%s", line_start);
4285 }
4286 }
4287 }
4288 }
4289
4290 // Verification
4291
4292 class VerifyFieldClosure: public BasicOopIterateClosure {
4293 protected:
4294 template <class T> void do_oop_work(T* p) {
4295 oop obj = RawAccess<>::oop_load(p);
4296 if (!oopDesc::is_oop_or_null(obj)) {
4297 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4298 Universe::print_on(tty);
4299 guarantee(false, "boom");
4300 }
4301 }
4302 public:
4303 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4304 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4305 };
4306
4307 void InstanceKlass::verify_on(outputStream* st) {
4308 #ifndef PRODUCT
4309 // Avoid redundant verifies, this really should be in product.
4310 if (_verify_count == Universe::verify_count()) return;
4311 _verify_count = Universe::verify_count();
4312 #endif
4313
4314 // Verify Klass
4315 Klass::verify_on(st);
4316
4317 // Verify that klass is present in ClassLoaderData
4318 guarantee(class_loader_data()->contains_klass(this),
4319 "this class isn't found in class loader data");
4320
4321 // Verify vtables
4322 if (is_linked()) {
4323 // $$$ This used to be done only for m/s collections. Doing it
4324 // always seemed a valid generalization. (DLD -- 6/00)
4325 vtable().verify(st);
4326 }
4327
4328 // Verify first subklass
4329 if (subklass() != nullptr) {
4330 guarantee(subklass()->is_klass(), "should be klass");
4331 }
4332
4333 // Verify siblings
4334 Klass* super = this->super();
4335 Klass* sib = next_sibling();
4336 if (sib != nullptr) {
4337 if (sib == this) {
4338 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4339 }
4340
4341 guarantee(sib->is_klass(), "should be klass");
4342 guarantee(sib->super() == super, "siblings should have same superklass");
4343 }
4344
4345 // Verify local interfaces
4346 if (local_interfaces()) {
4347 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4348 for (int j = 0; j < local_interfaces->length(); j++) {
4349 InstanceKlass* e = local_interfaces->at(j);
4350 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4351 }
4352 }
4353
4354 // Verify transitive interfaces
4355 if (transitive_interfaces() != nullptr) {
4356 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4357 for (int j = 0; j < transitive_interfaces->length(); j++) {
4358 InstanceKlass* e = transitive_interfaces->at(j);
4359 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4360 }
4361 }
4362
4363 // Verify methods
4364 if (methods() != nullptr) {
4365 Array<Method*>* methods = this->methods();
4366 for (int j = 0; j < methods->length(); j++) {
4367 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4368 }
4369 for (int j = 0; j < methods->length() - 1; j++) {
4370 Method* m1 = methods->at(j);
4371 Method* m2 = methods->at(j + 1);
4372 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4373 }
4374 }
4375
4376 // Verify method ordering
4377 if (method_ordering() != nullptr) {
4378 Array<int>* method_ordering = this->method_ordering();
4379 int length = method_ordering->length();
4380 if (JvmtiExport::can_maintain_original_method_order() ||
4381 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4382 guarantee(length == methods()->length(), "invalid method ordering length");
4383 jlong sum = 0;
4384 for (int j = 0; j < length; j++) {
4385 int original_index = method_ordering->at(j);
4386 guarantee(original_index >= 0, "invalid method ordering index");
4387 guarantee(original_index < length, "invalid method ordering index");
4388 sum += original_index;
4389 }
4390 // Verify sum of indices 0,1,...,length-1
4391 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4392 } else {
4393 guarantee(length == 0, "invalid method ordering length");
4394 }
4395 }
4396
4397 // Verify default methods
4398 if (default_methods() != nullptr) {
4399 Array<Method*>* methods = this->default_methods();
4400 for (int j = 0; j < methods->length(); j++) {
4401 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4402 }
4403 for (int j = 0; j < methods->length() - 1; j++) {
4404 Method* m1 = methods->at(j);
4405 Method* m2 = methods->at(j + 1);
4406 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4407 }
4408 }
4409
4410 // Verify JNI static field identifiers
4411 if (jni_ids() != nullptr) {
4412 jni_ids()->verify(this);
4413 }
4414
4415 // Verify other fields
4416 if (constants() != nullptr) {
4417 guarantee(constants()->is_constantPool(), "should be constant pool");
4418 }
4419 }
4420
4421 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4422 Klass::oop_verify_on(obj, st);
4423 VerifyFieldClosure blk;
4424 obj->oop_iterate(&blk);
4425 }
4426
4427
4428 // JNIid class for jfieldIDs only
4429 // Note to reviewers:
4430 // These JNI functions are just moved over to column 1 and not changed
4431 // in the compressed oops workspace.
4432 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4433 _holder = holder;
4434 _offset = offset;
4435 _next = next;
4436 debug_only(_is_static_field_id = false;)
4437 }
4438
4439
4440 JNIid* JNIid::find(int offset) {
4441 JNIid* current = this;
4442 while (current != nullptr) {
4443 if (current->offset() == offset) return current;
4444 current = current->next();
4445 }
4446 return nullptr;
4447 }
4448
4449 void JNIid::deallocate(JNIid* current) {
4450 while (current != nullptr) {
4451 JNIid* next = current->next();
4452 delete current;
4453 current = next;
4454 }
4455 }
4456
4457
4458 void JNIid::verify(Klass* holder) {
4459 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4460 int end_field_offset;
4461 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4462
4463 JNIid* current = this;
4464 while (current != nullptr) {
4465 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4466 #ifdef ASSERT
4467 int o = current->offset();
4468 if (current->is_static_field_id()) {
4469 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4470 }
4471 #endif
4472 current = current->next();
4473 }
4474 }
4475
4476 void InstanceKlass::set_init_state(ClassState state) {
4477 #ifdef ASSERT
4478 bool good_state = is_shared() ? (_init_state <= state)
4479 : (_init_state < state);
4480 assert(good_state || state == allocated, "illegal state transition");
4481 #endif
4482 assert(_init_thread == nullptr, "should be cleared before state change");
4483 Atomic::release_store(&_init_state, state);
4484 }
4485
4486 #if INCLUDE_JVMTI
4487
4488 // RedefineClasses() support for previous versions
4489
4490 // Globally, there is at least one previous version of a class to walk
4491 // during class unloading, which is saved because old methods in the class
4492 // are still running. Otherwise the previous version list is cleaned up.
4493 bool InstanceKlass::_should_clean_previous_versions = false;
4494
4495 // Returns true if there are previous versions of a class for class
4496 // unloading only. Also resets the flag to false. purge_previous_version
4497 // will set the flag to true if there are any left, i.e., if there's any
4498 // work to do for next time. This is to avoid the expensive code cache
4499 // walk in CLDG::clean_deallocate_lists().
4500 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4501 bool ret = _should_clean_previous_versions;
4502 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4503 ret ? "true" : "false");
4504 _should_clean_previous_versions = false;
4505 return ret;
4506 }
4507
4508 // This nulls out jmethodIDs for all methods in 'klass'
4509 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4510 // during class unloading.
4511 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4512 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4513 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4514 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4515 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4516 Array<Method*>* method_refs = klass->methods();
4517 for (int k = 0; k < method_refs->length(); k++) {
4518 Method* method = method_refs->at(k);
4519 if (method != nullptr && method->is_obsolete()) {
4520 method->clear_jmethod_id();
4521 }
4522 }
4523 }
4524
4525 // Purge previous versions before adding new previous versions of the class and
4526 // during class unloading.
4527 void InstanceKlass::purge_previous_version_list() {
4528 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4529 assert(has_been_redefined(), "Should only be called for main class");
4530
4531 // Quick exit.
4532 if (previous_versions() == nullptr) {
4533 return;
4534 }
4535
4536 // This klass has previous versions so see what we can cleanup
4537 // while it is safe to do so.
4538
4539 int deleted_count = 0; // leave debugging breadcrumbs
4540 int live_count = 0;
4541 ClassLoaderData* loader_data = class_loader_data();
4542 assert(loader_data != nullptr, "should never be null");
4543
4544 ResourceMark rm;
4545 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4546
4547 // previous versions are linked together through the InstanceKlass
4548 InstanceKlass* pv_node = previous_versions();
4549 InstanceKlass* last = this;
4550 int version = 0;
4551
4552 // check the previous versions list
4553 for (; pv_node != nullptr; ) {
4554
4555 ConstantPool* pvcp = pv_node->constants();
4556 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4557
4558 if (!pvcp->on_stack()) {
4559 // If the constant pool isn't on stack, none of the methods
4560 // are executing. Unlink this previous_version.
4561 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4562 // so will be deallocated during the next phase of class unloading.
4563 log_trace(redefine, class, iklass, purge)
4564 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4565 // Unlink from previous version list.
4566 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4567 InstanceKlass* next = pv_node->previous_versions();
4568 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4569 pv_node->link_previous_versions(nullptr); // point next to null
4570 last->link_previous_versions(next);
4571 // Delete this node directly. Nothing is referring to it and we don't
4572 // want it to increase the counter for metadata to delete in CLDG.
4573 MetadataFactory::free_metadata(loader_data, pv_node);
4574 pv_node = next;
4575 deleted_count++;
4576 version++;
4577 continue;
4578 } else {
4579 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4580 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4581 live_count++;
4582 if (pvcp->is_shared()) {
4583 // Shared previous versions can never be removed so no cleaning is needed.
4584 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4585 } else {
4586 // Previous version alive, set that clean is needed for next time.
4587 _should_clean_previous_versions = true;
4588 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4589 }
4590 }
4591
4592 // next previous version
4593 last = pv_node;
4594 pv_node = pv_node->previous_versions();
4595 version++;
4596 }
4597 log_trace(redefine, class, iklass, purge)
4598 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4599 }
4600
4601 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4602 int emcp_method_count) {
4603 int obsolete_method_count = old_methods->length() - emcp_method_count;
4604
4605 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4606 _previous_versions != nullptr) {
4607 // We have a mix of obsolete and EMCP methods so we have to
4608 // clear out any matching EMCP method entries the hard way.
4609 int local_count = 0;
4610 for (int i = 0; i < old_methods->length(); i++) {
4611 Method* old_method = old_methods->at(i);
4612 if (old_method->is_obsolete()) {
4613 // only obsolete methods are interesting
4614 Symbol* m_name = old_method->name();
4615 Symbol* m_signature = old_method->signature();
4616
4617 // previous versions are linked together through the InstanceKlass
4618 int j = 0;
4619 for (InstanceKlass* prev_version = _previous_versions;
4620 prev_version != nullptr;
4621 prev_version = prev_version->previous_versions(), j++) {
4622
4623 Array<Method*>* method_refs = prev_version->methods();
4624 for (int k = 0; k < method_refs->length(); k++) {
4625 Method* method = method_refs->at(k);
4626
4627 if (!method->is_obsolete() &&
4628 method->name() == m_name &&
4629 method->signature() == m_signature) {
4630 // The current RedefineClasses() call has made all EMCP
4631 // versions of this method obsolete so mark it as obsolete
4632 log_trace(redefine, class, iklass, add)
4633 ("%s(%s): flush obsolete method @%d in version @%d",
4634 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4635
4636 method->set_is_obsolete();
4637 break;
4638 }
4639 }
4640
4641 // The previous loop may not find a matching EMCP method, but
4642 // that doesn't mean that we can optimize and not go any
4643 // further back in the PreviousVersion generations. The EMCP
4644 // method for this generation could have already been made obsolete,
4645 // but there still may be an older EMCP method that has not
4646 // been made obsolete.
4647 }
4648
4649 if (++local_count >= obsolete_method_count) {
4650 // no more obsolete methods so bail out now
4651 break;
4652 }
4653 }
4654 }
4655 }
4656 }
4657
4658 // Save the scratch_class as the previous version if any of the methods are running.
4659 // The previous_versions are used to set breakpoints in EMCP methods and they are
4660 // also used to clean MethodData links to redefined methods that are no longer running.
4661 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4662 int emcp_method_count) {
4663 assert(Thread::current()->is_VM_thread(),
4664 "only VMThread can add previous versions");
4665
4666 ResourceMark rm;
4667 log_trace(redefine, class, iklass, add)
4668 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4669
4670 // Clean out old previous versions for this class
4671 purge_previous_version_list();
4672
4673 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4674 // a previous redefinition may be made obsolete by this redefinition.
4675 Array<Method*>* old_methods = scratch_class->methods();
4676 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4677
4678 // If the constant pool for this previous version of the class
4679 // is not marked as being on the stack, then none of the methods
4680 // in this previous version of the class are on the stack so
4681 // we don't need to add this as a previous version.
4682 ConstantPool* cp_ref = scratch_class->constants();
4683 if (!cp_ref->on_stack()) {
4684 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4685 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4686 return;
4687 }
4688
4689 // Add previous version if any methods are still running or if this is
4690 // a shared class which should never be removed.
4691 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4692 scratch_class->link_previous_versions(previous_versions());
4693 link_previous_versions(scratch_class);
4694 if (cp_ref->is_shared()) {
4695 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4696 } else {
4697 // We only set clean_previous_versions flag for processing during class
4698 // unloading for non-shared classes.
4699 _should_clean_previous_versions = true;
4700 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4701 }
4702 } // end add_previous_version()
4703
4704 #endif // INCLUDE_JVMTI
4705
4706 Method* InstanceKlass::method_with_idnum(int idnum) {
4707 Method* m = nullptr;
4708 if (idnum < methods()->length()) {
4709 m = methods()->at(idnum);
4710 }
4711 if (m == nullptr || m->method_idnum() != idnum) {
4712 for (int index = 0; index < methods()->length(); ++index) {
4713 m = methods()->at(index);
4714 if (m->method_idnum() == idnum) {
4715 return m;
4716 }
4717 }
4718 // None found, return null for the caller to handle.
4719 return nullptr;
4720 }
4721 return m;
4722 }
4723
4724
4725 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4726 if (idnum >= methods()->length()) {
4727 return nullptr;
4728 }
4729 Method* m = methods()->at(idnum);
4730 if (m != nullptr && m->orig_method_idnum() == idnum) {
4731 return m;
4732 }
4733 // Obsolete method idnum does not match the original idnum
4734 for (int index = 0; index < methods()->length(); ++index) {
4735 m = methods()->at(index);
4736 if (m->orig_method_idnum() == idnum) {
4737 return m;
4738 }
4739 }
4740 // None found, return null for the caller to handle.
4741 return nullptr;
4742 }
4743
4744
4745 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4746 InstanceKlass* holder = get_klass_version(version);
4747 if (holder == nullptr) {
4748 return nullptr; // The version of klass is gone, no method is found
4749 }
4750 Method* method = holder->method_with_orig_idnum(idnum);
4751 return method;
4752 }
4753
4754 #if INCLUDE_JVMTI
4755 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4756 return _cached_class_file;
4757 }
4758
4759 jint InstanceKlass::get_cached_class_file_len() {
4760 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4761 }
4762
4763 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4764 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4765 }
4766 #endif
4767
4768 // Make a step iterating over the class hierarchy under the root class.
4769 // Skips subclasses if requested.
4770 void ClassHierarchyIterator::next() {
4771 assert(_current != nullptr, "required");
4772 if (_visit_subclasses && _current->subklass() != nullptr) {
4773 _current = _current->subklass();
4774 return; // visit next subclass
4775 }
4776 _visit_subclasses = true; // reset
4777 while (_current->next_sibling() == nullptr && _current != _root) {
4778 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4779 }
4780 if (_current == _root) {
4781 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4782 _current = nullptr;
4783 return;
4784 }
4785 _current = _current->next_sibling();
4786 return; // visit next sibling subclass
4787 }