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