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/aotMetaspace.hpp"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/cdsEnumKlass.hpp"
30 #include "cds/classListWriter.hpp"
31 #include "cds/heapShared.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 "klass.inline.hpp"
54 #include "logging/log.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/constantPool.hpp"
65 #include "oops/fieldStreams.inline.hpp"
66 #include "oops/inlineKlass.hpp"
67 #include "oops/instanceClassLoaderKlass.hpp"
68 #include "oops/instanceKlass.inline.hpp"
69 #include "oops/instanceMirrorKlass.hpp"
70 #include "oops/instanceOop.hpp"
71 #include "oops/instanceStackChunkKlass.hpp"
72 #include "oops/klass.inline.hpp"
73 #include "oops/markWord.hpp"
74 #include "oops/method.hpp"
75 #include "oops/oop.inline.hpp"
76 #include "oops/recordComponent.hpp"
77 #include "oops/refArrayKlass.hpp"
78 #include "oops/symbol.hpp"
79 #include "prims/jvmtiExport.hpp"
80 #include "prims/jvmtiRedefineClasses.hpp"
81 #include "prims/jvmtiThreadState.hpp"
82 #include "prims/methodComparator.hpp"
83 #include "runtime/arguments.hpp"
84 #include "runtime/atomicAccess.hpp"
85 #include "runtime/deoptimization.hpp"
86 #include "runtime/fieldDescriptor.inline.hpp"
87 #include "runtime/handles.inline.hpp"
88 #include "runtime/javaCalls.hpp"
89 #include "runtime/javaThread.inline.hpp"
90 #include "runtime/mutexLocker.hpp"
91 #include "runtime/orderAccess.hpp"
92 #include "runtime/os.inline.hpp"
93 #include "runtime/reflection.hpp"
94 #include "runtime/synchronizer.hpp"
95 #include "runtime/threads.hpp"
96 #include "services/classLoadingService.hpp"
97 #include "services/finalizerService.hpp"
98 #include "services/threadService.hpp"
99 #include "utilities/dtrace.hpp"
100 #include "utilities/events.hpp"
101 #include "utilities/macros.hpp"
102 #include "utilities/nativeStackPrinter.hpp"
103 #include "utilities/stringUtils.hpp"
104 #ifdef COMPILER1
105 #include "c1/c1_Compiler.hpp"
106 #endif
107 #if INCLUDE_JFR
108 #include "jfr/jfrEvents.hpp"
109 #endif
110
111 #ifdef DTRACE_ENABLED
112
113
114 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
115 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
116 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
117 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
118 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
119 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
120 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
121 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
122 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
123 { \
124 char* data = nullptr; \
125 int len = 0; \
126 Symbol* clss_name = name(); \
127 if (clss_name != nullptr) { \
128 data = (char*)clss_name->bytes(); \
129 len = clss_name->utf8_length(); \
130 } \
131 HOTSPOT_CLASS_INITIALIZATION_##type( \
132 data, len, (void*)class_loader(), thread_type); \
133 }
134
135 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
136 { \
137 char* data = nullptr; \
138 int len = 0; \
139 Symbol* clss_name = name(); \
140 if (clss_name != nullptr) { \
141 data = (char*)clss_name->bytes(); \
142 len = clss_name->utf8_length(); \
143 } \
144 HOTSPOT_CLASS_INITIALIZATION_##type( \
145 data, len, (void*)class_loader(), thread_type, wait); \
146 }
147
148 #else // ndef DTRACE_ENABLED
149
150 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
151 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
152
153 #endif // ndef DTRACE_ENABLED
154
155 void InlineLayoutInfo::metaspace_pointers_do(MetaspaceClosure* it) {
156 log_trace(cds)("Iter(InlineFieldInfo): %p", this);
157 it->push(&_klass);
158 }
159
160 bool InstanceKlass::_finalization_enabled = true;
161
162 static inline bool is_class_loader(const Symbol* class_name,
163 const ClassFileParser& parser) {
164 assert(class_name != nullptr, "invariant");
165
166 if (class_name == vmSymbols::java_lang_ClassLoader()) {
167 return true;
168 }
169
170 if (vmClasses::ClassLoader_klass_is_loaded()) {
171 const Klass* const super_klass = parser.super_klass();
172 if (super_klass != nullptr) {
173 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
174 return true;
175 }
176 }
177 }
178 return false;
179 }
180
181 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
182 return field(index).field_flags().is_null_free_inline_type();
183 }
184
185 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
186 if (_loadable_descriptors == nullptr) return false;
187 for (int i = 0; i < _loadable_descriptors->length(); i++) {
188 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
189 if (class_name == name) return true;
190 }
191 return false;
192 }
193
194 static inline bool is_stack_chunk_class(const Symbol* class_name,
195 const ClassLoaderData* loader_data) {
196 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
197 loader_data->is_the_null_class_loader_data());
198 }
199
200 // private: called to verify that k is a static member of this nest.
201 // We know that k is an instance class in the same package and hence the
202 // same classloader.
203 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
204 assert(!is_hidden(), "unexpected hidden class");
205 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
206 if (log_is_enabled(Trace, class, nestmates)) {
207 ResourceMark rm(current);
208 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
209 k->external_name(), this->external_name());
210 }
211 return false;
212 }
213
214 if (log_is_enabled(Trace, class, nestmates)) {
215 ResourceMark rm(current);
216 log_trace(class, nestmates)("Checking nest membership of %s in %s",
217 k->external_name(), this->external_name());
218 }
219
220 // Check for the named class in _nest_members.
221 // We don't resolve, or load, any classes.
222 for (int i = 0; i < _nest_members->length(); i++) {
223 int cp_index = _nest_members->at(i);
224 Symbol* name = _constants->klass_name_at(cp_index);
225 if (name == k->name()) {
226 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
227 return true;
228 }
229 }
230 log_trace(class, nestmates)("- class is NOT a nest member!");
231 return false;
232 }
233
234 // Called to verify that k is a permitted subclass of this class.
235 // The incoming stringStream is used to format the messages for error logging and for the caller
236 // to use for exception throwing.
237 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
238 Thread* current = Thread::current();
239 assert(k != nullptr, "sanity check");
240 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
241 "unexpected empty _permitted_subclasses array");
242
243 if (log_is_enabled(Trace, class, sealed)) {
244 ResourceMark rm(current);
245 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
246 k->external_name(), this->external_name());
247 }
248
249 // Check that the class and its super are in the same module.
250 if (k->module() != this->module()) {
251 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
252 "and sealed class %s is in module '%s' with loader %s",
253 k->external_name(),
254 k->module()->name_as_C_string(),
255 k->module()->loader_data()->loader_name_and_id(),
256 this->external_name(),
257 this->module()->name_as_C_string(),
258 this->module()->loader_data()->loader_name_and_id());
259 log_trace(class, sealed)(" - %s", ss.as_string());
260 return false;
261 }
262
263 if (!k->is_public() && !is_same_class_package(k)) {
264 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
265 "and sealed class %s is in package '%s' with classloader %s",
266 k->external_name(),
267 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
268 k->module()->loader_data()->loader_name_and_id(),
269 this->external_name(),
270 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
271 this->module()->loader_data()->loader_name_and_id());
272 log_trace(class, sealed)(" - %s", ss.as_string());
273 return false;
274 }
275
276 for (int i = 0; i < _permitted_subclasses->length(); i++) {
277 int cp_index = _permitted_subclasses->at(i);
278 Symbol* name = _constants->klass_name_at(cp_index);
279 if (name == k->name()) {
280 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
281 return true;
282 }
283 }
284
285 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
286 k->external_name(), this->external_name());
287 log_trace(class, sealed)(" - %s", ss.as_string());
288 return false;
289 }
290
291 // Return nest-host class, resolving, validating and saving it if needed.
292 // In cases where this is called from a thread that cannot do classloading
293 // (such as a native JIT thread) then we simply return null, which in turn
294 // causes the access check to return false. Such code will retry the access
295 // from a more suitable environment later. Otherwise the _nest_host is always
296 // set once this method returns.
297 // Any errors from nest-host resolution must be preserved so they can be queried
298 // from higher-level access checking code, and reported as part of access checking
299 // exceptions.
300 // VirtualMachineErrors are propagated with a null return.
301 // Under any conditions where the _nest_host can be set to non-null the resulting
302 // value of it and, if applicable, the nest host resolution/validation error,
303 // are idempotent.
304 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
305 InstanceKlass* nest_host_k = _nest_host;
306 if (nest_host_k != nullptr) {
307 return nest_host_k;
308 }
309
310 ResourceMark rm(THREAD);
311
312 // need to resolve and save our nest-host class.
313 if (_nest_host_index != 0) { // we have a real nest_host
314 // Before trying to resolve check if we're in a suitable context
315 bool can_resolve = THREAD->can_call_java();
316 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
317 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
318 this->external_name());
319 return nullptr; // sentinel to say "try again from a different context"
320 }
321
322 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
323 this->external_name(),
324 _constants->klass_name_at(_nest_host_index)->as_C_string());
325
326 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
327 if (HAS_PENDING_EXCEPTION) {
328 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
329 return nullptr; // propagate VMEs
330 }
331 stringStream ss;
332 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
333 ss.print("Nest host resolution of %s with host %s failed: ",
334 this->external_name(), target_host_class);
335 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
336 const char* msg = ss.as_string(true /* on C-heap */);
337 constantPoolHandle cph(THREAD, constants());
338 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
339 CLEAR_PENDING_EXCEPTION;
340
341 log_trace(class, nestmates)("%s", msg);
342 } else {
343 // A valid nest-host is an instance class in the current package that lists this
344 // class as a nest member. If any of these conditions are not met the class is
345 // its own nest-host.
346 const char* error = nullptr;
347
348 // JVMS 5.4.4 indicates package check comes first
349 if (is_same_class_package(k)) {
350 // Now check actual membership. We can't be a member if our "host" is
351 // not an instance class.
352 if (k->is_instance_klass()) {
353 nest_host_k = InstanceKlass::cast(k);
354 bool is_member = nest_host_k->has_nest_member(THREAD, this);
355 if (is_member) {
356 _nest_host = nest_host_k; // save resolved nest-host value
357
358 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
359 this->external_name(), k->external_name());
360 return nest_host_k;
361 } else {
362 error = "current type is not listed as a nest member";
363 }
364 } else {
365 error = "host is not an instance class";
366 }
367 } else {
368 error = "types are in different packages";
369 }
370
371 // something went wrong, so record what and log it
372 {
373 stringStream ss;
374 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
375 this->external_name(),
376 this->class_loader_data()->loader_name_and_id(),
377 k->external_name(),
378 k->class_loader_data()->loader_name_and_id(),
379 error);
380 const char* msg = ss.as_string(true /* on C-heap */);
381 constantPoolHandle cph(THREAD, constants());
382 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
383 log_trace(class, nestmates)("%s", msg);
384 }
385 }
386 } else {
387 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
388 this->external_name());
389 }
390
391 // Either not in an explicit nest, or else an error occurred, so
392 // the nest-host is set to `this`. Any thread that sees this assignment
393 // will also see any setting of nest_host_error(), if applicable.
394 return (_nest_host = this);
395 }
396
397 // Dynamic nest member support: set this class's nest host to the given class.
398 // This occurs as part of the class definition, as soon as the instanceKlass
399 // has been created and doesn't require further resolution. The code:
400 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
401 // results in:
402 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
403 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
404 // We also know the "host" is a valid nest-host in the same package so we can
405 // assert some of those facts.
406 void InstanceKlass::set_nest_host(InstanceKlass* host) {
407 assert(is_hidden(), "must be a hidden class");
408 assert(host != nullptr, "null nest host specified");
409 assert(_nest_host == nullptr, "current class has resolved nest-host");
410 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
411 nest_host_error());
412 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
413 (host->_nest_host == host), "proposed host is not a valid nest-host");
414 // Can't assert this as package is not set yet:
415 // assert(is_same_class_package(host), "proposed host is in wrong package");
416
417 if (log_is_enabled(Trace, class, nestmates)) {
418 ResourceMark rm;
419 const char* msg = "";
420 // a hidden class does not expect a statically defined nest-host
421 if (_nest_host_index > 0) {
422 msg = "(the NestHost attribute in the current class is ignored)";
423 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
424 msg = "(the NestMembers attribute in the current class is ignored)";
425 }
426 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
427 this->external_name(),
428 host->external_name(),
429 msg);
430 }
431 // set dynamic nest host
432 _nest_host = host;
433 // Record dependency to keep nest host from being unloaded before this class.
434 ClassLoaderData* this_key = class_loader_data();
435 assert(this_key != nullptr, "sanity");
436 this_key->record_dependency(host);
437 }
438
439 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
440 // or we are k's nest_host - all of which is covered by comparing the two
441 // resolved_nest_hosts.
442 // Any exceptions (i.e. VMEs) are propagated.
443 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
444
445 assert(this != k, "this should be handled by higher-level code");
446
447 // Per JVMS 5.4.4 we first resolve and validate the current class, then
448 // the target class k.
449
450 InstanceKlass* cur_host = nest_host(CHECK_false);
451 if (cur_host == nullptr) {
452 return false;
453 }
454
455 Klass* k_nest_host = k->nest_host(CHECK_false);
456 if (k_nest_host == nullptr) {
457 return false;
458 }
459
460 bool access = (cur_host == k_nest_host);
461
462 ResourceMark rm(THREAD);
463 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
464 this->external_name(),
465 access ? "" : "NOT ",
466 k->external_name());
467 return access;
468 }
469
470 const char* InstanceKlass::nest_host_error() {
471 if (_nest_host_index == 0) {
472 return nullptr;
473 } else {
474 constantPoolHandle cph(Thread::current(), constants());
475 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
476 }
477 }
478
479 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
480 const int size = InstanceKlass::size(parser.vtable_size(),
481 parser.itable_size(),
482 nonstatic_oop_map_size(parser.total_oop_map_count()),
483 parser.is_interface(),
484 parser.is_inline_type());
485
486 const Symbol* const class_name = parser.class_name();
487 assert(class_name != nullptr, "invariant");
488 ClassLoaderData* loader_data = parser.loader_data();
489 assert(loader_data != nullptr, "invariant");
490
491 InstanceKlass* ik;
492
493 // Allocation
494 if (parser.is_instance_ref_klass()) {
495 // java.lang.ref.Reference
496 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
497 } else if (class_name == vmSymbols::java_lang_Class()) {
498 // mirror - java.lang.Class
499 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
500 } else if (is_stack_chunk_class(class_name, loader_data)) {
501 // stack chunk
502 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
503 } else if (is_class_loader(class_name, parser)) {
504 // class loader - java.lang.ClassLoader
505 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
506 } else if (parser.is_inline_type()) {
507 // inline type
508 ik = new (loader_data, size, THREAD) InlineKlass(parser);
509 } else {
510 // normal
511 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
512 }
513
514 if (ik != nullptr && UseCompressedClassPointers) {
515 assert(CompressedKlassPointers::is_encodable(ik),
516 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
517 }
518
519 // Check for pending exception before adding to the loader data and incrementing
520 // class count. Can get OOM here.
521 if (HAS_PENDING_EXCEPTION) {
522 return nullptr;
523 }
524
525 #ifdef ASSERT
526 ik->bounds_check((address) ik->start_of_vtable(), false, size);
527 ik->bounds_check((address) ik->start_of_itable(), false, size);
528 ik->bounds_check((address) ik->end_of_itable(), true, size);
529 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
530 #endif //ASSERT
531 return ik;
532 }
533
534 #ifndef PRODUCT
535 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
536 const char* bad = nullptr;
537 address end = nullptr;
538 if (addr < (address)this) {
539 bad = "before";
540 } else if (addr == (address)this) {
541 if (edge_ok) return true;
542 bad = "just before";
543 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
544 if (edge_ok) return true;
545 bad = "just after";
546 } else if (addr > end) {
547 bad = "after";
548 } else {
549 return true;
550 }
551 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
552 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
553 Verbose = WizardMode = true; this->print(); //@@
554 return false;
555 }
556 #endif //PRODUCT
557
558 // copy method ordering from resource area to Metaspace
559 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
560 if (m != nullptr) {
561 // allocate a new array and copy contents (memcpy?)
562 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
563 for (int i = 0; i < m->length(); i++) {
564 _method_ordering->at_put(i, m->at(i));
565 }
566 } else {
567 _method_ordering = Universe::the_empty_int_array();
568 }
569 }
570
571 // create a new array of vtable_indices for default methods
572 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
573 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
574 assert(default_vtable_indices() == nullptr, "only create once");
575 set_default_vtable_indices(vtable_indices);
576 return vtable_indices;
577 }
578
579
580 InstanceKlass::InstanceKlass() {
581 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
582 }
583
584 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, markWord prototype_header, ReferenceType reference_type) :
585 Klass(kind, prototype_header),
586 _nest_members(nullptr),
587 _nest_host(nullptr),
588 _permitted_subclasses(nullptr),
589 _record_components(nullptr),
590 _static_field_size(parser.static_field_size()),
591 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
592 _itable_len(parser.itable_size()),
593 _nest_host_index(0),
594 _init_state(allocated),
595 _reference_type(reference_type),
596 _acmp_maps_offset(0),
597 _init_thread(nullptr),
598 _inline_layout_info_array(nullptr),
599 _loadable_descriptors(nullptr),
600 _adr_inlineklass_fixed_block(nullptr)
601 {
602 set_vtable_length(parser.vtable_size());
603 set_access_flags(parser.access_flags());
604 if (parser.is_hidden()) set_is_hidden();
605 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
606 false));
607 if (parser.has_inline_fields()) {
608 set_has_inline_type_fields();
609 }
610
611 assert(nullptr == _methods, "underlying memory not zeroed?");
612 assert(is_instance_klass(), "is layout incorrect?");
613 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
614 }
615
616 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
617 Array<Method*>* methods) {
618 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
619 !methods->in_aot_cache()) {
620 for (int i = 0; i < methods->length(); i++) {
621 Method* method = methods->at(i);
622 if (method == nullptr) continue; // maybe null if error processing
623 // Only want to delete methods that are not executing for RedefineClasses.
624 // The previous version will point to them so they're not totally dangling
625 assert (!method->on_stack(), "shouldn't be called with methods on stack");
626 MetadataFactory::free_metadata(loader_data, method);
627 }
628 MetadataFactory::free_array<Method*>(loader_data, methods);
629 }
630 }
631
632 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
633 const InstanceKlass* super_klass,
634 Array<InstanceKlass*>* local_interfaces,
635 Array<InstanceKlass*>* transitive_interfaces) {
636 // Only deallocate transitive interfaces if not empty, same as super class
637 // or same as local interfaces. See code in parseClassFile.
638 Array<InstanceKlass*>* ti = transitive_interfaces;
639 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
640 // check that the interfaces don't come from super class
641 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
642 super_klass->transitive_interfaces();
643 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
644 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
645 }
646 }
647
648 // local interfaces can be empty
649 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
650 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
651 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
652 }
653 }
654
655 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
656 Array<RecordComponent*>* record_components) {
657 if (record_components != nullptr && !record_components->in_aot_cache()) {
658 for (int i = 0; i < record_components->length(); i++) {
659 RecordComponent* record_component = record_components->at(i);
660 MetadataFactory::free_metadata(loader_data, record_component);
661 }
662 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
663 }
664 }
665
666 // This function deallocates the metadata and C heap pointers that the
667 // InstanceKlass points to.
668 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
669 // Orphan the mirror first, CMS thinks it's still live.
670 if (java_mirror() != nullptr) {
671 java_lang_Class::set_klass(java_mirror(), nullptr);
672 }
673
674 // Also remove mirror from handles
675 loader_data->remove_handle(_java_mirror);
676
677 // Need to take this class off the class loader data list.
678 loader_data->remove_class(this);
679
680 // The array_klass for this class is created later, after error handling.
681 // For class redefinition, we keep the original class so this scratch class
682 // doesn't have an array class. Either way, assert that there is nothing
683 // to deallocate.
684 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
685
686 // Release C heap allocated data that this points to, which includes
687 // reference counting symbol names.
688 // Can't release the constant pool or MethodData C heap data here because the constant
689 // pool can be deallocated separately from the InstanceKlass for default methods and
690 // redefine classes. MethodData can also be released separately.
691 release_C_heap_structures(/* release_sub_metadata */ false);
692
693 deallocate_methods(loader_data, methods());
694 set_methods(nullptr);
695
696 deallocate_record_components(loader_data, record_components());
697 set_record_components(nullptr);
698
699 if (method_ordering() != nullptr &&
700 method_ordering() != Universe::the_empty_int_array() &&
701 !method_ordering()->in_aot_cache()) {
702 MetadataFactory::free_array<int>(loader_data, method_ordering());
703 }
704 set_method_ordering(nullptr);
705
706 // default methods can be empty
707 if (default_methods() != nullptr &&
708 default_methods() != Universe::the_empty_method_array() &&
709 !default_methods()->in_aot_cache()) {
710 MetadataFactory::free_array<Method*>(loader_data, default_methods());
711 }
712 // Do NOT deallocate the default methods, they are owned by superinterfaces.
713 set_default_methods(nullptr);
714
715 // default methods vtable indices can be empty
716 if (default_vtable_indices() != nullptr &&
717 !default_vtable_indices()->in_aot_cache()) {
718 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
719 }
720 set_default_vtable_indices(nullptr);
721
722
723 // This array is in Klass, but remove it with the InstanceKlass since
724 // this place would be the only caller and it can share memory with transitive
725 // interfaces.
726 if (secondary_supers() != nullptr &&
727 secondary_supers() != Universe::the_empty_klass_array() &&
728 // see comments in compute_secondary_supers about the following cast
729 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
730 !secondary_supers()->in_aot_cache()) {
731 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
732 }
733 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
734
735 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
736 set_transitive_interfaces(nullptr);
737 set_local_interfaces(nullptr);
738
739 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
740 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
741 }
742 set_fieldinfo_stream(nullptr);
743
744 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
745 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
746 }
747 set_fieldinfo_search_table(nullptr);
748
749 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
750 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
751 }
752 set_fields_status(nullptr);
753
754 if (inline_layout_info_array() != nullptr) {
755 MetadataFactory::free_array<InlineLayoutInfo>(loader_data, inline_layout_info_array());
756 }
757 set_inline_layout_info_array(nullptr);
758
759 // If a method from a redefined class is using this constant pool, don't
760 // delete it, yet. The new class's previous version will point to this.
761 if (constants() != nullptr) {
762 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
763 if (!constants()->in_aot_cache()) {
764 MetadataFactory::free_metadata(loader_data, constants());
765 }
766 // Delete any cached resolution errors for the constant pool
767 SystemDictionary::delete_resolution_error(constants());
768
769 set_constants(nullptr);
770 }
771
772 if (inner_classes() != nullptr &&
773 inner_classes() != Universe::the_empty_short_array() &&
774 !inner_classes()->in_aot_cache()) {
775 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
776 }
777 set_inner_classes(nullptr);
778
779 if (nest_members() != nullptr &&
780 nest_members() != Universe::the_empty_short_array() &&
781 !nest_members()->in_aot_cache()) {
782 MetadataFactory::free_array<jushort>(loader_data, nest_members());
783 }
784 set_nest_members(nullptr);
785
786 if (permitted_subclasses() != nullptr &&
787 permitted_subclasses() != Universe::the_empty_short_array() &&
788 !permitted_subclasses()->in_aot_cache()) {
789 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
790 }
791 set_permitted_subclasses(nullptr);
792
793 if (loadable_descriptors() != nullptr &&
794 loadable_descriptors() != Universe::the_empty_short_array() &&
795 !loadable_descriptors()->in_aot_cache()) {
796 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
797 }
798 set_loadable_descriptors(nullptr);
799
800 // We should deallocate the Annotations instance if it's not in shared spaces.
801 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
802 MetadataFactory::free_metadata(loader_data, annotations());
803 }
804 set_annotations(nullptr);
805
806 SystemDictionaryShared::handle_class_unloading(this);
807
808 #if INCLUDE_CDS_JAVA_HEAP
809 if (CDSConfig::is_dumping_heap()) {
810 HeapShared::remove_scratch_objects(this);
811 }
812 #endif
813 }
814
815 bool InstanceKlass::is_record() const {
816 return _record_components != nullptr &&
817 is_final() &&
818 super() == vmClasses::Record_klass();
819 }
820
821 bool InstanceKlass::is_sealed() const {
822 return _permitted_subclasses != nullptr &&
823 _permitted_subclasses != Universe::the_empty_short_array();
824 }
825
826 // JLS 8.9: An enum class is either implicitly final and derives
827 // from java.lang.Enum, or else is implicitly sealed to its
828 // anonymous subclasses. This query detects both kinds.
829 // It does not validate the finality or
830 // sealing conditions: it merely checks for a super of Enum.
831 // This is sufficient for recognizing well-formed enums.
832 bool InstanceKlass::is_enum_subclass() const {
833 InstanceKlass* s = super();
834 return (s == vmClasses::Enum_klass() ||
835 (s != nullptr && s->super() == vmClasses::Enum_klass()));
836 }
837
838 bool InstanceKlass::should_be_initialized() const {
839 return !is_initialized();
840 }
841
842 klassItable InstanceKlass::itable() const {
843 return klassItable(const_cast<InstanceKlass*>(this));
844 }
845
846 // JVMTI spec thinks there are signers and protection domain in the
847 // instanceKlass. These accessors pretend these fields are there.
848 // The hprof specification also thinks these fields are in InstanceKlass.
849 oop InstanceKlass::protection_domain() const {
850 // return the protection_domain from the mirror
851 return java_lang_Class::protection_domain(java_mirror());
852 }
853
854 objArrayOop InstanceKlass::signers() const {
855 // return the signers from the mirror
856 return java_lang_Class::signers(java_mirror());
857 }
858
859 oop InstanceKlass::init_lock() const {
860 // return the init lock from the mirror
861 oop lock = java_lang_Class::init_lock(java_mirror());
862 // Prevent reordering with any access of initialization state
863 OrderAccess::loadload();
864 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
865 "only fully initialized state can have a null lock");
866 return lock;
867 }
868
869 // Set the initialization lock to null so the object can be GC'ed. Any racing
870 // threads to get this lock will see a null lock and will not lock.
871 // That's okay because they all check for initialized state after getting
872 // the lock and return.
873 void InstanceKlass::fence_and_clear_init_lock() {
874 // make sure previous stores are all done, notably the init_state.
875 OrderAccess::storestore();
876 java_lang_Class::clear_init_lock(java_mirror());
877 assert(!is_not_initialized(), "class must be initialized now");
878 }
879
880
881 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
882 // process. The step comments refers to the procedure described in that section.
883 // Note: implementation moved to static method to expose the this pointer.
884 void InstanceKlass::initialize(TRAPS) {
885 if (this->should_be_initialized()) {
886 initialize_impl(CHECK);
887 // Note: at this point the class may be initialized
888 // OR it may be in the state of being initialized
889 // in case of recursive initialization!
890 } else {
891 assert(is_initialized(), "sanity check");
892 }
893 }
894
895 #ifdef ASSERT
896 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
897 assert(has_aot_initialized_mirror(), "must be");
898
899 InstanceKlass* s = super();
900 if (s != nullptr) {
901 DEBUG_ONLY(ResourceMark rm);
902 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
903 s->external_name(), external_name());
904 s->assert_no_clinit_will_run_for_aot_initialized_class();
905 }
906
907 Array<InstanceKlass*>* interfaces = local_interfaces();
908 int len = interfaces->length();
909 for (int i = 0; i < len; i++) {
910 InstanceKlass* intf = interfaces->at(i);
911 if (!intf->is_initialized()) {
912 ResourceMark rm;
913 // Note: an interface needs to be marked as is_initialized() only if
914 // - it has a <clinit>
915 // - it has declared a default method.
916 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
917 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
918 intf->external_name(), external_name());
919 }
920 }
921 }
922 #endif
923
924 #if INCLUDE_CDS
925 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
926 assert(has_aot_initialized_mirror(), "must be");
927 assert(CDSConfig::is_loading_heap(), "must be");
928 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
929 assert_no_clinit_will_run_for_aot_initialized_class();
930
931 if (is_initialized()) {
932 return;
933 }
934
935 if (is_runtime_setup_required()) {
936 // Need to take the slow path, which will call the runtimeSetup() function instead
937 // of <clinit>
938 initialize(CHECK);
939 return;
940 }
941 if (log_is_enabled(Info, aot, init)) {
942 ResourceMark rm;
943 log_info(aot, init)("%s (aot-inited)", external_name());
944 }
945
946 link_class(CHECK);
947
948 #ifdef ASSERT
949 {
950 Handle h_init_lock(THREAD, init_lock());
951 ObjectLocker ol(h_init_lock, THREAD);
952 assert(!is_initialized(), "sanity");
953 assert(!is_being_initialized(), "sanity");
954 assert(!is_in_error_state(), "sanity");
955 }
956 #endif
957
958 set_init_thread(THREAD);
959 set_initialization_state_and_notify(fully_initialized, CHECK);
960 }
961 #endif
962
963 bool InstanceKlass::verify_code(TRAPS) {
964 // 1) Verify the bytecodes
965 return Verifier::verify(this, should_verify_class(), THREAD);
966 }
967
968 static void load_classes_from_loadable_descriptors_attribute(InstanceKlass *ik, TRAPS) {
969 ResourceMark rm(THREAD);
970 if (ik->loadable_descriptors() != nullptr && PreloadClasses) {
971 HandleMark hm(THREAD);
972 for (int i = 0; i < ik->loadable_descriptors()->length(); i++) {
973 Symbol* sig = ik->constants()->symbol_at(ik->loadable_descriptors()->at(i));
974 if (!Signature::has_envelope(sig)) continue;
975 TempNewSymbol class_name = Signature::strip_envelope(sig);
976 if (class_name == ik->name()) continue;
977 log_info(class, preload)("Preloading of class %s during linking of class %s "
978 "because of the class is listed in the LoadableDescriptors attribute",
979 sig->as_C_string(), ik->name()->as_C_string());
980 oop loader = ik->class_loader();
981 Klass* klass = SystemDictionary::resolve_or_null(class_name,
982 Handle(THREAD, loader), THREAD);
983 if (HAS_PENDING_EXCEPTION) {
984 CLEAR_PENDING_EXCEPTION;
985 }
986 if (klass != nullptr) {
987 log_info(class, preload)("Preloading of class %s during linking of class %s "
988 "(cause: LoadableDescriptors attribute) succeeded",
989 class_name->as_C_string(), ik->name()->as_C_string());
990 if (!klass->is_inline_klass()) {
991 // Non value class are allowed by the current spec, but it could be an indication
992 // of an issue so let's log a warning
993 log_info(class, preload)("Preloading of class %s during linking of class %s "
994 "(cause: LoadableDescriptors attribute) but loaded class is not a value class",
995 class_name->as_C_string(), ik->name()->as_C_string());
996 }
997 } else {
998 log_info(class, preload)("Preloading of class %s during linking of class %s "
999 "(cause: LoadableDescriptors attribute) failed",
1000 class_name->as_C_string(), ik->name()->as_C_string());
1001 }
1002 }
1003 }
1004 }
1005
1006 void InstanceKlass::link_class(TRAPS) {
1007 assert(is_loaded(), "must be loaded");
1008 if (!is_linked()) {
1009 link_class_impl(CHECK);
1010 }
1011 }
1012
1013 // Called to verify that a class can link during initialization, without
1014 // throwing a VerifyError.
1015 bool InstanceKlass::link_class_or_fail(TRAPS) {
1016 assert(is_loaded(), "must be loaded");
1017 if (!is_linked()) {
1018 link_class_impl(CHECK_false);
1019 }
1020 return is_linked();
1021 }
1022
1023 bool InstanceKlass::link_class_impl(TRAPS) {
1024 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
1025 // This is for CDS static dump only -- we use the in_error_state to indicate that
1026 // the class has failed verification. Throwing the NoClassDefFoundError here is just
1027 // a convenient way to stop repeat attempts to verify the same (bad) class.
1028 //
1029 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
1030 // if we are executing Java code. This is not a problem for CDS dumping phase since
1031 // it doesn't execute any Java code.
1032 ResourceMark rm(THREAD);
1033 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1034 Exceptions::fthrow(THREAD_AND_LOCATION,
1035 vmSymbols::java_lang_NoClassDefFoundError(),
1036 "Class %s, or one of its supertypes, failed class initialization",
1037 external_name());
1038 return false;
1039 }
1040 // return if already verified
1041 if (is_linked()) {
1042 return true;
1043 }
1044
1045 // Timing
1046 // timer handles recursion
1047 JavaThread* jt = THREAD;
1048
1049 // link super class before linking this class
1050 InstanceKlass* super_klass = super();
1051 if (super_klass != nullptr) {
1052 if (super_klass->is_interface()) { // check if super class is an interface
1053 ResourceMark rm(THREAD);
1054 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1055 Exceptions::fthrow(
1056 THREAD_AND_LOCATION,
1057 vmSymbols::java_lang_IncompatibleClassChangeError(),
1058 "class %s has interface %s as super class",
1059 external_name(),
1060 super_klass->external_name()
1061 );
1062 return false;
1063 }
1064
1065 super_klass->link_class_impl(CHECK_false);
1066 }
1067
1068 // link all interfaces implemented by this class before linking this class
1069 Array<InstanceKlass*>* interfaces = local_interfaces();
1070 int num_interfaces = interfaces->length();
1071 for (int index = 0; index < num_interfaces; index++) {
1072 InstanceKlass* interk = interfaces->at(index);
1073 interk->link_class_impl(CHECK_false);
1074 }
1075
1076 if (EnableValhalla) {
1077 // Aggressively preloading all classes from the LoadableDescriptors attribute
1078 // so inline classes can be scalarized in the calling conventions computed below
1079 load_classes_from_loadable_descriptors_attribute(this, THREAD);
1080 assert(!HAS_PENDING_EXCEPTION, "Shouldn't have pending exceptions from call above");
1081 }
1082
1083 // in case the class is linked in the process of linking its superclasses
1084 if (is_linked()) {
1085 return true;
1086 }
1087
1088 // trace only the link time for this klass that includes
1089 // the verification time
1090 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1091 ClassLoader::perf_class_link_selftime(),
1092 ClassLoader::perf_classes_linked(),
1093 jt->get_thread_stat()->perf_recursion_counts_addr(),
1094 jt->get_thread_stat()->perf_timers_addr(),
1095 PerfClassTraceTime::CLASS_LINK);
1096
1097 // verification & rewriting
1098 {
1099 HandleMark hm(THREAD);
1100 Handle h_init_lock(THREAD, init_lock());
1101 ObjectLocker ol(h_init_lock, jt);
1102 // rewritten will have been set if loader constraint error found
1103 // on an earlier link attempt
1104 // don't verify or rewrite if already rewritten
1105 //
1106
1107 if (!is_linked()) {
1108 if (!is_rewritten()) {
1109 if (in_aot_cache()) {
1110 assert(!verified_at_dump_time(), "must be");
1111 }
1112 {
1113 bool verify_ok = verify_code(THREAD);
1114 if (!verify_ok) {
1115 return false;
1116 }
1117 }
1118
1119 // Just in case a side-effect of verify linked this class already
1120 // (which can sometimes happen since the verifier loads classes
1121 // using custom class loaders, which are free to initialize things)
1122 if (is_linked()) {
1123 return true;
1124 }
1125
1126 // also sets rewritten
1127 rewrite_class(CHECK_false);
1128 } else if (in_aot_cache()) {
1129 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1130 }
1131
1132 // relocate jsrs and link methods after they are all rewritten
1133 link_methods(CHECK_false);
1134
1135 // Initialize the vtable and interface table after
1136 // methods have been rewritten since rewrite may
1137 // fabricate new Method*s.
1138 // also does loader constraint checking
1139 //
1140 // initialize_vtable and initialize_itable need to be rerun
1141 // for a shared class if
1142 // 1) the class is loaded by custom class loader or
1143 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1144 // 3) the class was not verified during dump time
1145 bool need_init_table = true;
1146 if (in_aot_cache() && verified_at_dump_time() &&
1147 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1148 need_init_table = false;
1149 }
1150 if (need_init_table) {
1151 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1152 itable().initialize_itable_and_check_constraints(CHECK_false);
1153 }
1154 #ifdef ASSERT
1155 vtable().verify(tty, true);
1156 // In case itable verification is ever added.
1157 // itable().verify(tty, true);
1158 #endif
1159 if (Universe::is_fully_initialized()) {
1160 DeoptimizationScope deopt_scope;
1161 {
1162 // Now mark all code that assumes the class is not linked.
1163 // Set state under the Compile_lock also.
1164 MutexLocker ml(THREAD, Compile_lock);
1165
1166 set_init_state(linked);
1167 CodeCache::mark_dependents_on(&deopt_scope, this);
1168 }
1169 // Perform the deopt handshake outside Compile_lock.
1170 deopt_scope.deoptimize_marked();
1171 } else {
1172 set_init_state(linked);
1173 }
1174 if (JvmtiExport::should_post_class_prepare()) {
1175 JvmtiExport::post_class_prepare(THREAD, this);
1176 }
1177 }
1178 }
1179 return true;
1180 }
1181
1182 // Rewrite the byte codes of all of the methods of a class.
1183 // The rewriter must be called exactly once. Rewriting must happen after
1184 // verification but before the first method of the class is executed.
1185 void InstanceKlass::rewrite_class(TRAPS) {
1186 assert(is_loaded(), "must be loaded");
1187 if (is_rewritten()) {
1188 assert(in_aot_cache(), "rewriting an unshared class?");
1189 return;
1190 }
1191 Rewriter::rewrite(this, CHECK);
1192 set_rewritten();
1193 }
1194
1195 // Now relocate and link method entry points after class is rewritten.
1196 // This is outside is_rewritten flag. In case of an exception, it can be
1197 // executed more than once.
1198 void InstanceKlass::link_methods(TRAPS) {
1199 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1200
1201 int len = methods()->length();
1202 for (int i = len-1; i >= 0; i--) {
1203 methodHandle m(THREAD, methods()->at(i));
1204
1205 // Set up method entry points for compiler and interpreter .
1206 m->link_method(m, CHECK);
1207 }
1208 }
1209
1210 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1211 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1212 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1213 for (int i = 0; i < local_interfaces()->length(); ++i) {
1214 InstanceKlass* ik = local_interfaces()->at(i);
1215
1216 // Initialization is depth first search ie. we start with top of the inheritance tree
1217 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1218 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1219 if (ik->has_nonstatic_concrete_methods()) {
1220 ik->initialize_super_interfaces(CHECK);
1221 }
1222
1223 // Only initialize() interfaces that "declare" concrete methods.
1224 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1225 ik->initialize(CHECK);
1226 }
1227 }
1228 }
1229
1230 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1231 static InitializationErrorTable* _initialization_error_table;
1232
1233 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1234 // Create the same exception with a message indicating the thread name,
1235 // and the StackTraceElements.
1236 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1237 ResourceMark rm(current);
1238 if (init_error.is_null()) {
1239 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1240
1241 // We failed to create the new exception, most likely due to either out-of-memory or
1242 // a stackoverflow error. If the original exception was either of those then we save
1243 // the shared, pre-allocated, stackless, instance of that exception.
1244 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1245 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1246 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1247 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1248 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1249 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1250 } else {
1251 return;
1252 }
1253 }
1254
1255 MutexLocker ml(current, ClassInitError_lock);
1256 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1257 bool created;
1258 if (_initialization_error_table == nullptr) {
1259 _initialization_error_table = new (mtClass) InitializationErrorTable();
1260 }
1261 _initialization_error_table->put_if_absent(this, elem, &created);
1262 assert(created, "Initialization is single threaded");
1263 log_trace(class, init)("Initialization error added for class %s", external_name());
1264 }
1265
1266 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1267 MutexLocker ml(current, ClassInitError_lock);
1268 if (_initialization_error_table == nullptr) {
1269 return nullptr;
1270 }
1271 OopHandle* h = _initialization_error_table->get(this);
1272 return (h != nullptr) ? h->resolve() : nullptr;
1273 }
1274
1275 // Need to remove entries for unloaded classes.
1276 void InstanceKlass::clean_initialization_error_table() {
1277 struct InitErrorTableCleaner {
1278 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1279 if (!ik->is_loader_alive()) {
1280 h.release(Universe::vm_global());
1281 return true;
1282 } else {
1283 return false;
1284 }
1285 }
1286 };
1287
1288 assert_locked_or_safepoint(ClassInitError_lock);
1289 InitErrorTableCleaner cleaner;
1290 if (_initialization_error_table != nullptr) {
1291 _initialization_error_table->unlink(&cleaner);
1292 }
1293 }
1294
1295 void InstanceKlass::initialize_impl(TRAPS) {
1296 HandleMark hm(THREAD);
1297
1298 // Make sure klass is linked (verified) before initialization
1299 // A class could already be verified, since it has been reflected upon.
1300 link_class(CHECK);
1301
1302 DTRACE_CLASSINIT_PROBE(required, -1);
1303
1304 bool wait = false;
1305
1306 JavaThread* jt = THREAD;
1307
1308 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1309
1310 // refer to the JVM book page 47 for description of steps
1311 // Step 1
1312 {
1313 Handle h_init_lock(THREAD, init_lock());
1314 ObjectLocker ol(h_init_lock, jt);
1315
1316 // Step 2
1317 // If we were to use wait() instead of waitInterruptibly() then
1318 // we might end up throwing IE from link/symbol resolution sites
1319 // that aren't expected to throw. This would wreak havoc. See 6320309.
1320 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1321 if (debug_logging_enabled) {
1322 ResourceMark rm(jt);
1323 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1324 jt->name(), external_name(), init_thread_name());
1325 }
1326 wait = true;
1327 jt->set_class_to_be_initialized(this);
1328 ol.wait_uninterruptibly(jt);
1329 jt->set_class_to_be_initialized(nullptr);
1330 }
1331
1332 // Step 3
1333 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1334 if (debug_logging_enabled) {
1335 ResourceMark rm(jt);
1336 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1337 jt->name(), external_name());
1338 }
1339 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1340 return;
1341 }
1342
1343 // Step 4
1344 if (is_initialized()) {
1345 if (debug_logging_enabled) {
1346 ResourceMark rm(jt);
1347 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1348 jt->name(), external_name());
1349 }
1350 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1351 return;
1352 }
1353
1354 // Step 5
1355 if (is_in_error_state()) {
1356 if (debug_logging_enabled) {
1357 ResourceMark rm(jt);
1358 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1359 jt->name(), external_name());
1360 }
1361
1362 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1363 ResourceMark rm(THREAD);
1364 Handle cause(THREAD, get_initialization_error(THREAD));
1365
1366 stringStream ss;
1367 ss.print("Could not initialize class %s", external_name());
1368 if (cause.is_null()) {
1369 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1370 } else {
1371 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1372 ss.as_string(), cause);
1373 }
1374 } else {
1375
1376 // Step 6
1377 set_init_state(being_initialized);
1378 set_init_thread(jt);
1379 if (debug_logging_enabled) {
1380 ResourceMark rm(jt);
1381 log_debug(class, init)("Thread \"%s\" is initializing %s",
1382 jt->name(), external_name());
1383 }
1384 }
1385 }
1386
1387 // Pre-allocating an all-zero value to be used to reset nullable flat storages
1388 if (is_inline_klass()) {
1389 InlineKlass* vk = InlineKlass::cast(this);
1390 if (vk->has_nullable_atomic_layout()) {
1391 oop val = vk->allocate_instance(THREAD);
1392 if (HAS_PENDING_EXCEPTION) {
1393 Handle e(THREAD, PENDING_EXCEPTION);
1394 CLEAR_PENDING_EXCEPTION;
1395 {
1396 EXCEPTION_MARK;
1397 add_initialization_error(THREAD, e);
1398 // Locks object, set state, and notify all waiting threads
1399 set_initialization_state_and_notify(initialization_error, THREAD);
1400 CLEAR_PENDING_EXCEPTION;
1401 }
1402 THROW_OOP(e());
1403 }
1404 vk->set_null_reset_value(val);
1405 }
1406 }
1407
1408 // Step 7
1409 // Next, if C is a class rather than an interface, initialize it's super class and super
1410 // interfaces.
1411 if (!is_interface()) {
1412 Klass* super_klass = super();
1413 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1414 super_klass->initialize(THREAD);
1415 }
1416 // If C implements any interface that declares a non-static, concrete method,
1417 // the initialization of C triggers initialization of its super interfaces.
1418 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1419 // having a superinterface that declares, non-static, concrete methods
1420 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1421 initialize_super_interfaces(THREAD);
1422 }
1423
1424 // If any exceptions, complete abruptly, throwing the same exception as above.
1425 if (HAS_PENDING_EXCEPTION) {
1426 Handle e(THREAD, PENDING_EXCEPTION);
1427 CLEAR_PENDING_EXCEPTION;
1428 {
1429 EXCEPTION_MARK;
1430 add_initialization_error(THREAD, e);
1431 // Locks object, set state, and notify all waiting threads
1432 set_initialization_state_and_notify(initialization_error, THREAD);
1433 CLEAR_PENDING_EXCEPTION;
1434 }
1435 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1436 THROW_OOP(e());
1437 }
1438 }
1439
1440 // Step 8
1441 {
1442 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1443 if (class_initializer() != nullptr) {
1444 // Timer includes any side effects of class initialization (resolution,
1445 // etc), but not recursive entry into call_class_initializer().
1446 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1447 ClassLoader::perf_class_init_selftime(),
1448 ClassLoader::perf_classes_inited(),
1449 jt->get_thread_stat()->perf_recursion_counts_addr(),
1450 jt->get_thread_stat()->perf_timers_addr(),
1451 PerfClassTraceTime::CLASS_CLINIT);
1452 call_class_initializer(THREAD);
1453 } else {
1454 // The elapsed time is so small it's not worth counting.
1455 if (UsePerfData) {
1456 ClassLoader::perf_classes_inited()->inc();
1457 }
1458 call_class_initializer(THREAD);
1459 }
1460
1461 if (has_strict_static_fields() && !HAS_PENDING_EXCEPTION) {
1462 // Step 9 also verifies that strict static fields have been initialized.
1463 // Status bits were set in ClassFileParser::post_process_parsed_stream.
1464 // After <clinit>, bits must all be clear, or else we must throw an error.
1465 // This is an extremely fast check, so we won't bother with a timer.
1466 assert(fields_status() != nullptr, "");
1467 Symbol* bad_strict_static = nullptr;
1468 for (int index = 0; index < fields_status()->length(); index++) {
1469 // Very fast loop over single byte array looking for a set bit.
1470 if (fields_status()->adr_at(index)->is_strict_static_unset()) {
1471 // This strict static field has not been set by the class initializer.
1472 // Note that in the common no-error case, we read no field metadata.
1473 // We only unpack it when we need to report an error.
1474 FieldInfo fi = field(index);
1475 bad_strict_static = fi.name(constants());
1476 if (debug_logging_enabled) {
1477 ResourceMark rm(jt);
1478 const char* msg = format_strict_static_message(bad_strict_static);
1479 log_debug(class, init)("%s", msg);
1480 } else {
1481 // If we are not logging, do not bother to look for a second offense.
1482 break;
1483 }
1484 }
1485 }
1486 if (bad_strict_static != nullptr) {
1487 throw_strict_static_exception(bad_strict_static, "is unset after initialization of", THREAD);
1488 }
1489 }
1490 }
1491
1492 // Step 9
1493 if (!HAS_PENDING_EXCEPTION) {
1494 set_initialization_state_and_notify(fully_initialized, CHECK);
1495 DEBUG_ONLY(vtable().verify(tty, true);)
1496 CompilationPolicy::replay_training_at_init(this, THREAD);
1497 }
1498 else {
1499 // Step 10 and 11
1500 Handle e(THREAD, PENDING_EXCEPTION);
1501 CLEAR_PENDING_EXCEPTION;
1502 // JVMTI has already reported the pending exception
1503 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1504 JvmtiExport::clear_detected_exception(jt);
1505 {
1506 EXCEPTION_MARK;
1507 add_initialization_error(THREAD, e);
1508 set_initialization_state_and_notify(initialization_error, THREAD);
1509 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1510 // JVMTI has already reported the pending exception
1511 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1512 JvmtiExport::clear_detected_exception(jt);
1513 }
1514 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1515 if (e->is_a(vmClasses::Error_klass())) {
1516 THROW_OOP(e());
1517 } else {
1518 JavaCallArguments args(e);
1519 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1520 vmSymbols::throwable_void_signature(),
1521 &args);
1522 }
1523 }
1524 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1525 }
1526
1527
1528 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1529 Handle h_init_lock(THREAD, init_lock());
1530 if (h_init_lock() != nullptr) {
1531 ObjectLocker ol(h_init_lock, THREAD);
1532 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1533 set_init_state(state);
1534 fence_and_clear_init_lock();
1535 ol.notify_all(CHECK);
1536 } else {
1537 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1538 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1539 set_init_state(state);
1540 }
1541 }
1542
1543 void InstanceKlass::notify_strict_static_access(int field_index, bool is_writing, TRAPS) {
1544 guarantee(field_index >= 0 && field_index < fields_status()->length(), "valid field index");
1545 DEBUG_ONLY(FieldInfo debugfi = field(field_index));
1546 assert(debugfi.access_flags().is_strict(), "");
1547 assert(debugfi.access_flags().is_static(), "");
1548 FieldStatus& fs = *fields_status()->adr_at(field_index);
1549 LogTarget(Trace, class, init) lt;
1550 if (lt.is_enabled()) {
1551 ResourceMark rm(THREAD);
1552 LogStream ls(lt);
1553 FieldInfo fi = field(field_index);
1554 ls.print("notify %s %s %s%s ",
1555 external_name(), is_writing? "Write" : "Read",
1556 fs.is_strict_static_unset() ? "Unset" : "(set)",
1557 fs.is_strict_static_unread() ? "+Unread" : "");
1558 fi.print(&ls, constants());
1559 }
1560 if (fs.is_strict_static_unset()) {
1561 assert(fs.is_strict_static_unread(), "ClassFileParser resp.");
1562 // If it is not set, there are only two reasonable things we can do here:
1563 // - mark it set if this is putstatic
1564 // - throw an error (Read-Before-Write) if this is getstatic
1565
1566 // The unset state is (or should be) transient, and observable only in one
1567 // thread during the execution of <clinit>. Something is wrong here as this
1568 // should not be possible
1569 guarantee(is_reentrant_initialization(THREAD), "unscoped access to strict static");
1570 if (is_writing) {
1571 // clear the "unset" bit, since the field is actually going to be written
1572 fs.update_strict_static_unset(false);
1573 } else {
1574 // throw an IllegalStateException, since we are reading before writing
1575 // see also InstanceKlass::initialize_impl, Step 8 (at end)
1576 Symbol* bad_strict_static = field(field_index).name(constants());
1577 throw_strict_static_exception(bad_strict_static, "is unset before first read in", CHECK);
1578 }
1579 } else {
1580 // Ensure no write after read for final strict statics
1581 FieldInfo fi = field(field_index);
1582 bool is_final = fi.access_flags().is_final();
1583 if (is_final) {
1584 // no final write after read, so observing a constant freezes it, as if <clinit> ended early
1585 // (maybe we could trust the constant a little earlier, before <clinit> ends)
1586 if (is_writing && !fs.is_strict_static_unread()) {
1587 Symbol* bad_strict_static = fi.name(constants());
1588 throw_strict_static_exception(bad_strict_static, "is set after read (as final) in", CHECK);
1589 } else if (!is_writing && fs.is_strict_static_unread()) {
1590 fs.update_strict_static_unread(false);
1591 }
1592 }
1593 }
1594 }
1595
1596 void InstanceKlass::throw_strict_static_exception(Symbol* field_name, const char* when, TRAPS) {
1597 ResourceMark rm(THREAD);
1598 const char* msg = format_strict_static_message(field_name, when);
1599 THROW_MSG(vmSymbols::java_lang_IllegalStateException(), msg);
1600 }
1601
1602 const char* InstanceKlass::format_strict_static_message(Symbol* field_name, const char* when) {
1603 stringStream ss;
1604 ss.print("Strict static \"%s\" %s %s",
1605 field_name->as_C_string(),
1606 when == nullptr ? "is unset in" : when,
1607 external_name());
1608 return ss.as_string();
1609 }
1610
1611 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1612 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1613 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1614 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1615
1616 DeoptimizationScope deopt_scope;
1617 {
1618 MutexLocker ml(current, Compile_lock);
1619
1620 set_init_state(InstanceKlass::loaded);
1621 // make sure init_state store is already done.
1622 // The compiler reads the hierarchy outside of the Compile_lock.
1623 // Access ordering is used to add to hierarchy.
1624
1625 // Link into hierarchy.
1626 append_to_sibling_list(); // add to superklass/sibling list
1627 process_interfaces(); // handle all "implements" declarations
1628
1629 // Now mark all code that depended on old class hierarchy.
1630 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1631 if (Universe::is_fully_initialized()) {
1632 CodeCache::mark_dependents_on(&deopt_scope, this);
1633 }
1634 }
1635 // Perform the deopt handshake outside Compile_lock.
1636 deopt_scope.deoptimize_marked();
1637 }
1638
1639
1640 InstanceKlass* InstanceKlass::implementor() const {
1641 InstanceKlass* volatile* ik = adr_implementor();
1642 if (ik == nullptr) {
1643 return nullptr;
1644 } else {
1645 // This load races with inserts, and therefore needs acquire.
1646 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1647 if (ikls != nullptr && !ikls->is_loader_alive()) {
1648 return nullptr; // don't return unloaded class
1649 } else {
1650 return ikls;
1651 }
1652 }
1653 }
1654
1655
1656 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1657 assert_locked_or_safepoint(Compile_lock);
1658 assert(is_interface(), "not interface");
1659 InstanceKlass* volatile* addr = adr_implementor();
1660 assert(addr != nullptr, "null addr");
1661 if (addr != nullptr) {
1662 AtomicAccess::release_store(addr, ik);
1663 }
1664 }
1665
1666 int InstanceKlass::nof_implementors() const {
1667 InstanceKlass* ik = implementor();
1668 if (ik == nullptr) {
1669 return 0;
1670 } else if (ik != this) {
1671 return 1;
1672 } else {
1673 return 2;
1674 }
1675 }
1676
1677 // The embedded _implementor field can only record one implementor.
1678 // When there are more than one implementors, the _implementor field
1679 // is set to the interface Klass* itself. Following are the possible
1680 // values for the _implementor field:
1681 // null - no implementor
1682 // implementor Klass* - one implementor
1683 // self - more than one implementor
1684 //
1685 // The _implementor field only exists for interfaces.
1686 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1687 if (Universe::is_fully_initialized()) {
1688 assert_lock_strong(Compile_lock);
1689 }
1690 assert(is_interface(), "not interface");
1691 // Filter out my subinterfaces.
1692 // (Note: Interfaces are never on the subklass list.)
1693 if (ik->is_interface()) return;
1694
1695 // Filter out subclasses whose supers already implement me.
1696 // (Note: CHA must walk subclasses of direct implementors
1697 // in order to locate indirect implementors.)
1698 InstanceKlass* super_ik = ik->super();
1699 if (super_ik != nullptr && super_ik->implements_interface(this))
1700 // We only need to check one immediate superclass, since the
1701 // implements_interface query looks at transitive_interfaces.
1702 // Any supers of the super have the same (or fewer) transitive_interfaces.
1703 return;
1704
1705 InstanceKlass* iklass = implementor();
1706 if (iklass == nullptr) {
1707 set_implementor(ik);
1708 } else if (iklass != this && iklass != ik) {
1709 // There is already an implementor. Use itself as an indicator of
1710 // more than one implementors.
1711 set_implementor(this);
1712 }
1713
1714 // The implementor also implements the transitive_interfaces
1715 for (int index = 0; index < local_interfaces()->length(); index++) {
1716 local_interfaces()->at(index)->add_implementor(ik);
1717 }
1718 }
1719
1720 void InstanceKlass::init_implementor() {
1721 if (is_interface()) {
1722 set_implementor(nullptr);
1723 }
1724 }
1725
1726
1727 void InstanceKlass::process_interfaces() {
1728 // link this class into the implementors list of every interface it implements
1729 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1730 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1731 InstanceKlass* interf = local_interfaces()->at(i);
1732 assert(interf->is_interface(), "expected interface");
1733 interf->add_implementor(this);
1734 }
1735 }
1736
1737 bool InstanceKlass::can_be_primary_super_slow() const {
1738 if (is_interface())
1739 return false;
1740 else
1741 return Klass::can_be_primary_super_slow();
1742 }
1743
1744 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1745 Array<InstanceKlass*>* transitive_interfaces) {
1746 // The secondaries are the implemented interfaces.
1747 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1748 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1749 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1750 int num_secondaries = num_extra_slots + interfaces->length();
1751 if (num_secondaries == 0) {
1752 // Must share this for correct bootstrapping!
1753 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1754 return nullptr;
1755 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1756 // We will reuse the transitive interfaces list if we're certain
1757 // it's in hash order.
1758 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1759 set_secondary_supers(interfaces, bitmap);
1760 return nullptr;
1761 }
1762 // Copy transitive interfaces to a temporary growable array to be constructed
1763 // into the secondary super list with extra slots.
1764 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1765 for (int i = 0; i < interfaces->length(); i++) {
1766 secondaries->push(interfaces->at(i));
1767 }
1768 return secondaries;
1769 }
1770
1771 bool InstanceKlass::implements_interface(Klass* k) const {
1772 if (this == k) return true;
1773 assert(k->is_interface(), "should be an interface class");
1774 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1775 if (transitive_interfaces()->at(i) == k) {
1776 return true;
1777 }
1778 }
1779 return false;
1780 }
1781
1782 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1783 // Verify direct super interface
1784 if (this == k) return true;
1785 assert(k->is_interface(), "should be an interface class");
1786 for (int i = 0; i < local_interfaces()->length(); i++) {
1787 if (local_interfaces()->at(i) == k) {
1788 return true;
1789 }
1790 }
1791 return false;
1792 }
1793
1794 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1795 if (TraceFinalizerRegistration) {
1796 tty->print("Registered ");
1797 i->print_value_on(tty);
1798 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1799 }
1800 instanceHandle h_i(THREAD, i);
1801 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1802 JavaValue result(T_VOID);
1803 JavaCallArguments args(h_i);
1804 methodHandle mh(THREAD, Universe::finalizer_register_method());
1805 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1806 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1807 return h_i();
1808 }
1809
1810 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1811 assert(!is_abstract() && !is_interface(), "Should not create this object");
1812 size_t size = size_helper(); // Query before forming handle.
1813 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1814 }
1815
1816 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1817 Klass* k = java_lang_Class::as_Klass(java_class);
1818 if (k == nullptr) {
1819 ResourceMark rm(THREAD);
1820 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1821 }
1822 InstanceKlass* ik = cast(k);
1823 ik->check_valid_for_instantiation(false, CHECK_NULL);
1824 ik->initialize(CHECK_NULL);
1825 return ik->allocate_instance(THREAD);
1826 }
1827
1828 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1829 return instanceHandle(THREAD, allocate_instance(THREAD));
1830 }
1831
1832 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1833 if (is_interface() || is_abstract()) {
1834 ResourceMark rm(THREAD);
1835 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1836 : vmSymbols::java_lang_InstantiationException(), external_name());
1837 }
1838 if (this == vmClasses::Class_klass()) {
1839 ResourceMark rm(THREAD);
1840 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1841 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1842 }
1843 }
1844
1845 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1846 // Need load-acquire for lock-free read
1847 if (array_klasses_acquire() == nullptr) {
1848
1849 // Recursively lock array allocation
1850 RecursiveLocker rl(MultiArray_lock, THREAD);
1851
1852 // Check if another thread created the array klass while we were waiting for the lock.
1853 if (array_klasses() == nullptr) {
1854 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1855 // use 'release' to pair with lock-free load
1856 release_set_array_klasses(k);
1857 }
1858 }
1859
1860 // array_klasses() will always be set at this point
1861 ArrayKlass* ak = array_klasses();
1862 assert(ak != nullptr, "should be set");
1863 return ak->array_klass(n, THREAD);
1864 }
1865
1866 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1867 // Need load-acquire for lock-free read
1868 ArrayKlass* ak = array_klasses_acquire();
1869 if (ak == nullptr) {
1870 return nullptr;
1871 } else {
1872 return ak->array_klass_or_null(n);
1873 }
1874 }
1875
1876 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1877 return array_klass(1, THREAD);
1878 }
1879
1880 ArrayKlass* InstanceKlass::array_klass_or_null() {
1881 return array_klass_or_null(1);
1882 }
1883
1884 static int call_class_initializer_counter = 0; // for debugging
1885
1886 Method* InstanceKlass::class_initializer() const {
1887 Method* clinit = find_method(
1888 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1889 if (clinit != nullptr && clinit->is_class_initializer()) {
1890 return clinit;
1891 }
1892 return nullptr;
1893 }
1894
1895 void InstanceKlass::call_class_initializer(TRAPS) {
1896 if (ReplayCompiles &&
1897 (ReplaySuppressInitializers == 1 ||
1898 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1899 // Hide the existence of the initializer for the purpose of replaying the compile
1900 return;
1901 }
1902
1903 #if INCLUDE_CDS
1904 // This is needed to ensure the consistency of the archived heap objects.
1905 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1906 AOTClassInitializer::call_runtime_setup(THREAD, this);
1907 return;
1908 } else if (has_archived_enum_objs()) {
1909 assert(in_aot_cache(), "must be");
1910 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1911 if (initialized) {
1912 return;
1913 }
1914 }
1915 #endif
1916
1917 methodHandle h_method(THREAD, class_initializer());
1918 assert(!is_initialized(), "we cannot initialize twice");
1919 LogTarget(Info, class, init) lt;
1920 if (lt.is_enabled()) {
1921 ResourceMark rm(THREAD);
1922 LogStream ls(lt);
1923 ls.print("%d Initializing ", call_class_initializer_counter++);
1924 name()->print_value_on(&ls);
1925 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1926 h_method() == nullptr ? "(no method)" : "", p2i(this),
1927 THREAD->name());
1928 }
1929 if (h_method() != nullptr) {
1930 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1931 JavaCallArguments args; // No arguments
1932 JavaValue result(T_VOID);
1933 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1934 }
1935 }
1936
1937 // If a class that implements this interface is initialized, is the JVM required
1938 // to first execute a <clinit> method declared in this interface,
1939 // or (if also_check_supers==true) any of the super types of this interface?
1940 //
1941 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1942 // an interface, then let SC be its superclass and let SI1, ..., SIn
1943 // be all superinterfaces of C (whether direct or indirect) that
1944 // declare at least one non-abstract, non-static method.
1945 //
1946 // So when an interface is initialized, it does not look at its
1947 // supers. But a proper class will ensure that all of its supers have
1948 // run their <clinit> methods, except that it disregards interfaces
1949 // that lack a non-static concrete method (i.e., a default method).
1950 // Therefore, you should probably call this method only when the
1951 // current class is a super of some proper class, not an interface.
1952 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1953 assert(is_interface(), "must be");
1954
1955 if (!has_nonstatic_concrete_methods()) {
1956 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1957 return false;
1958 }
1959
1960 // JVMS 5.5. Initialization
1961 // ...If C is an interface that declares a non-abstract,
1962 // non-static method, the initialization of a class that
1963 // implements C directly or indirectly.
1964 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1965 return true;
1966 }
1967 if (also_check_supers) {
1968 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1969 for (int i = 0; i < all_ifs->length(); ++i) {
1970 InstanceKlass* super_intf = all_ifs->at(i);
1971 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1972 return true;
1973 }
1974 }
1975 }
1976 return false;
1977 }
1978
1979 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1980 InterpreterOopMap* entry_for) {
1981 // Lazily create the _oop_map_cache at first request.
1982 // Load_acquire is needed to safely get instance published with CAS by another thread.
1983 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
1984 if (oop_map_cache == nullptr) {
1985 // Try to install new instance atomically.
1986 oop_map_cache = new OopMapCache();
1987 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1988 if (other != nullptr) {
1989 // Someone else managed to install before us, ditch local copy and use the existing one.
1990 delete oop_map_cache;
1991 oop_map_cache = other;
1992 }
1993 }
1994 // _oop_map_cache is constant after init; lookup below does its own locking.
1995 oop_map_cache->lookup(method, bci, entry_for);
1996 }
1997
1998
1999 FieldInfo InstanceKlass::field(int index) const {
2000 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2001 if (fs.index() == index) {
2002 return fs.to_FieldInfo();
2003 }
2004 }
2005 fatal("Field not found");
2006 return FieldInfo();
2007 }
2008
2009 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2010 JavaFieldStream fs(this);
2011 if (fs.lookup(name, sig)) {
2012 assert(fs.name() == name, "name must match");
2013 assert(fs.signature() == sig, "signature must match");
2014 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2015 return true;
2016 }
2017 return false;
2018 }
2019
2020
2021 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2022 const int n = local_interfaces()->length();
2023 for (int i = 0; i < n; i++) {
2024 InstanceKlass* intf1 = local_interfaces()->at(i);
2025 assert(intf1->is_interface(), "just checking type");
2026 // search for field in current interface
2027 if (intf1->find_local_field(name, sig, fd)) {
2028 assert(fd->is_static(), "interface field must be static");
2029 return intf1;
2030 }
2031 // search for field in direct superinterfaces
2032 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
2033 if (intf2 != nullptr) return intf2;
2034 }
2035 // otherwise field lookup fails
2036 return nullptr;
2037 }
2038
2039
2040 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2041 // search order according to newest JVM spec (5.4.3.2, p.167).
2042 // 1) search for field in current klass
2043 if (find_local_field(name, sig, fd)) {
2044 return const_cast<InstanceKlass*>(this);
2045 }
2046 // 2) search for field recursively in direct superinterfaces
2047 { Klass* intf = find_interface_field(name, sig, fd);
2048 if (intf != nullptr) return intf;
2049 }
2050 // 3) apply field lookup recursively if superclass exists
2051 { InstanceKlass* supr = super();
2052 if (supr != nullptr) return supr->find_field(name, sig, fd);
2053 }
2054 // 4) otherwise field lookup fails
2055 return nullptr;
2056 }
2057
2058
2059 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
2060 // search order according to newest JVM spec (5.4.3.2, p.167).
2061 // 1) search for field in current klass
2062 if (find_local_field(name, sig, fd)) {
2063 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
2064 }
2065 // 2) search for field recursively in direct superinterfaces
2066 if (is_static) {
2067 Klass* intf = find_interface_field(name, sig, fd);
2068 if (intf != nullptr) return intf;
2069 }
2070 // 3) apply field lookup recursively if superclass exists
2071 { InstanceKlass* supr = super();
2072 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
2073 }
2074 // 4) otherwise field lookup fails
2075 return nullptr;
2076 }
2077
2078 bool InstanceKlass::contains_field_offset(int offset) {
2079 if (this->is_inline_klass()) {
2080 InlineKlass* vk = InlineKlass::cast(this);
2081 return offset >= vk->payload_offset() && offset < (vk->payload_offset() + vk->payload_size_in_bytes());
2082 } else {
2083 fieldDescriptor fd;
2084 return find_field_from_offset(offset, false, &fd);
2085 }
2086 }
2087
2088 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2089 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2090 if (fs.offset() == offset) {
2091 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2092 if (fd->is_static() == is_static) return true;
2093 }
2094 }
2095 return false;
2096 }
2097
2098
2099 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2100 const InstanceKlass* klass = this;
2101 while (klass != nullptr) {
2102 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
2103 return true;
2104 }
2105 klass = klass->super();
2106 }
2107 return false;
2108 }
2109
2110
2111 void InstanceKlass::methods_do(void f(Method* method)) {
2112 // Methods aren't stable until they are loaded. This can be read outside
2113 // a lock through the ClassLoaderData for profiling
2114 // Redefined scratch classes are on the list and need to be cleaned
2115 if (!is_loaded() && !is_scratch_class()) {
2116 return;
2117 }
2118
2119 int len = methods()->length();
2120 for (int index = 0; index < len; index++) {
2121 Method* m = methods()->at(index);
2122 assert(m->is_method(), "must be method");
2123 f(m);
2124 }
2125 }
2126
2127
2128 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2129 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2130 if (fs.access_flags().is_static()) {
2131 fieldDescriptor& fd = fs.field_descriptor();
2132 cl->do_field(&fd);
2133 }
2134 }
2135 }
2136
2137
2138 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2139 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2140 if (fs.access_flags().is_static()) {
2141 fieldDescriptor& fd = fs.field_descriptor();
2142 f(&fd, mirror, CHECK);
2143 }
2144 }
2145 }
2146
2147 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2148 InstanceKlass* super = this->super();
2149 if (super != nullptr) {
2150 super->do_nonstatic_fields(cl);
2151 }
2152 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2153 fieldDescriptor& fd = fs.field_descriptor();
2154 if (!fd.is_static()) {
2155 cl->do_field(&fd);
2156 }
2157 }
2158 }
2159
2160 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2161 return a->offset() - b->offset();
2162 }
2163
2164 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2165 InstanceKlass* super = this->super();
2166 if (super != nullptr) {
2167 super->print_nonstatic_fields(cl);
2168 }
2169 ResourceMark rm;
2170 // In DebugInfo nonstatic fields are sorted by offset.
2171 GrowableArray<FieldInfo> fields_sorted;
2172 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2173 if (!fs.access_flags().is_static()) {
2174 fields_sorted.push(fs.to_FieldInfo());
2175 }
2176 }
2177 int length = fields_sorted.length();
2178 if (length > 0) {
2179 fields_sorted.sort(compare_fields_by_offset);
2180 fieldDescriptor fd;
2181 for (int i = 0; i < length; i++) {
2182 fd.reinitialize(this, fields_sorted.at(i));
2183 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2184 cl->do_field(&fd);
2185 }
2186 }
2187 }
2188
2189 #ifdef ASSERT
2190 static int linear_search(const Array<Method*>* methods,
2191 const Symbol* name,
2192 const Symbol* signature) {
2193 const int len = methods->length();
2194 for (int index = 0; index < len; index++) {
2195 const Method* const m = methods->at(index);
2196 assert(m->is_method(), "must be method");
2197 if (m->signature() == signature && m->name() == name) {
2198 return index;
2199 }
2200 }
2201 return -1;
2202 }
2203 #endif
2204
2205 bool InstanceKlass::_disable_method_binary_search = false;
2206
2207 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2208 int len = methods->length();
2209 int l = 0;
2210 int h = len - 1;
2211 while (l <= h) {
2212 Method* m = methods->at(l);
2213 if (m->name() == name) {
2214 return l;
2215 }
2216 l++;
2217 }
2218 return -1;
2219 }
2220
2221 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2222 if (_disable_method_binary_search) {
2223 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2224 // At the final stage of dynamic dumping, the methods array may not be sorted
2225 // by ascending addresses of their names, so we can't use binary search anymore.
2226 // However, methods with the same name are still laid out consecutively inside the
2227 // methods array, so let's look for the first one that matches.
2228 return linear_search(methods, name);
2229 }
2230
2231 int len = methods->length();
2232 int l = 0;
2233 int h = len - 1;
2234
2235 // methods are sorted by ascending addresses of their names, so do binary search
2236 while (l <= h) {
2237 int mid = (l + h) >> 1;
2238 Method* m = methods->at(mid);
2239 assert(m->is_method(), "must be method");
2240 int res = m->name()->fast_compare(name);
2241 if (res == 0) {
2242 return mid;
2243 } else if (res < 0) {
2244 l = mid + 1;
2245 } else {
2246 h = mid - 1;
2247 }
2248 }
2249 return -1;
2250 }
2251
2252 // find_method looks up the name/signature in the local methods array
2253 Method* InstanceKlass::find_method(const Symbol* name,
2254 const Symbol* signature) const {
2255 return find_method_impl(name, signature,
2256 OverpassLookupMode::find,
2257 StaticLookupMode::find,
2258 PrivateLookupMode::find);
2259 }
2260
2261 Method* InstanceKlass::find_method_impl(const Symbol* name,
2262 const Symbol* signature,
2263 OverpassLookupMode overpass_mode,
2264 StaticLookupMode static_mode,
2265 PrivateLookupMode private_mode) const {
2266 return InstanceKlass::find_method_impl(methods(),
2267 name,
2268 signature,
2269 overpass_mode,
2270 static_mode,
2271 private_mode);
2272 }
2273
2274 // find_instance_method looks up the name/signature in the local methods array
2275 // and skips over static methods
2276 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2277 const Symbol* name,
2278 const Symbol* signature,
2279 PrivateLookupMode private_mode) {
2280 Method* const meth = InstanceKlass::find_method_impl(methods,
2281 name,
2282 signature,
2283 OverpassLookupMode::find,
2284 StaticLookupMode::skip,
2285 private_mode);
2286 assert(((meth == nullptr) || !meth->is_static()),
2287 "find_instance_method should have skipped statics");
2288 return meth;
2289 }
2290
2291 // find_instance_method looks up the name/signature in the local methods array
2292 // and skips over static methods
2293 Method* InstanceKlass::find_instance_method(const Symbol* name,
2294 const Symbol* signature,
2295 PrivateLookupMode private_mode) const {
2296 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2297 }
2298
2299 // Find looks up the name/signature in the local methods array
2300 // and filters on the overpass, static and private flags
2301 // This returns the first one found
2302 // note that the local methods array can have up to one overpass, one static
2303 // and one instance (private or not) with the same name/signature
2304 Method* InstanceKlass::find_local_method(const Symbol* name,
2305 const Symbol* signature,
2306 OverpassLookupMode overpass_mode,
2307 StaticLookupMode static_mode,
2308 PrivateLookupMode private_mode) const {
2309 return InstanceKlass::find_method_impl(methods(),
2310 name,
2311 signature,
2312 overpass_mode,
2313 static_mode,
2314 private_mode);
2315 }
2316
2317 // Find looks up the name/signature in the local methods array
2318 // and filters on the overpass, static and private flags
2319 // This returns the first one found
2320 // note that the local methods array can have up to one overpass, one static
2321 // and one instance (private or not) with the same name/signature
2322 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2323 const Symbol* name,
2324 const Symbol* signature,
2325 OverpassLookupMode overpass_mode,
2326 StaticLookupMode static_mode,
2327 PrivateLookupMode private_mode) {
2328 return InstanceKlass::find_method_impl(methods,
2329 name,
2330 signature,
2331 overpass_mode,
2332 static_mode,
2333 private_mode);
2334 }
2335
2336 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2337 const Symbol* name,
2338 const Symbol* signature) {
2339 return InstanceKlass::find_method_impl(methods,
2340 name,
2341 signature,
2342 OverpassLookupMode::find,
2343 StaticLookupMode::find,
2344 PrivateLookupMode::find);
2345 }
2346
2347 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2348 const Symbol* name,
2349 const Symbol* signature,
2350 OverpassLookupMode overpass_mode,
2351 StaticLookupMode static_mode,
2352 PrivateLookupMode private_mode) {
2353 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2354 return hit >= 0 ? methods->at(hit): nullptr;
2355 }
2356
2357 // true if method matches signature and conforms to skipping_X conditions.
2358 static bool method_matches(const Method* m,
2359 const Symbol* signature,
2360 bool skipping_overpass,
2361 bool skipping_static,
2362 bool skipping_private) {
2363 return ((m->signature() == signature) &&
2364 (!skipping_overpass || !m->is_overpass()) &&
2365 (!skipping_static || !m->is_static()) &&
2366 (!skipping_private || !m->is_private()));
2367 }
2368
2369 // Used directly for default_methods to find the index into the
2370 // default_vtable_indices, and indirectly by find_method
2371 // find_method_index looks in the local methods array to return the index
2372 // of the matching name/signature. If, overpass methods are being ignored,
2373 // the search continues to find a potential non-overpass match. This capability
2374 // is important during method resolution to prefer a static method, for example,
2375 // over an overpass method.
2376 // There is the possibility in any _method's array to have the same name/signature
2377 // for a static method, an overpass method and a local instance method
2378 // To correctly catch a given method, the search criteria may need
2379 // to explicitly skip the other two. For local instance methods, it
2380 // is often necessary to skip private methods
2381 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2382 const Symbol* name,
2383 const Symbol* signature,
2384 OverpassLookupMode overpass_mode,
2385 StaticLookupMode static_mode,
2386 PrivateLookupMode private_mode) {
2387 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2388 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2389 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2390 const int hit = quick_search(methods, name);
2391 if (hit != -1) {
2392 const Method* const m = methods->at(hit);
2393
2394 // Do linear search to find matching signature. First, quick check
2395 // for common case, ignoring overpasses if requested.
2396 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2397 return hit;
2398 }
2399
2400 // search downwards through overloaded methods
2401 int i;
2402 for (i = hit - 1; i >= 0; --i) {
2403 const Method* const m = methods->at(i);
2404 assert(m->is_method(), "must be method");
2405 if (m->name() != name) {
2406 break;
2407 }
2408 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2409 return i;
2410 }
2411 }
2412 // search upwards
2413 for (i = hit + 1; i < methods->length(); ++i) {
2414 const Method* const m = methods->at(i);
2415 assert(m->is_method(), "must be method");
2416 if (m->name() != name) {
2417 break;
2418 }
2419 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2420 return i;
2421 }
2422 }
2423 // not found
2424 #ifdef ASSERT
2425 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2426 linear_search(methods, name, signature);
2427 assert(-1 == index, "binary search should have found entry %d", index);
2428 #endif
2429 }
2430 return -1;
2431 }
2432
2433 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2434 return find_method_by_name(methods(), name, end);
2435 }
2436
2437 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2438 const Symbol* name,
2439 int* end_ptr) {
2440 assert(end_ptr != nullptr, "just checking");
2441 int start = quick_search(methods, name);
2442 int end = start + 1;
2443 if (start != -1) {
2444 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2445 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2446 *end_ptr = end;
2447 return start;
2448 }
2449 return -1;
2450 }
2451
2452 // uncached_lookup_method searches both the local class methods array and all
2453 // superclasses methods arrays, skipping any overpass methods in superclasses,
2454 // and possibly skipping private methods.
2455 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2456 const Symbol* signature,
2457 OverpassLookupMode overpass_mode,
2458 PrivateLookupMode private_mode) const {
2459 OverpassLookupMode overpass_local_mode = overpass_mode;
2460 const InstanceKlass* klass = this;
2461 while (klass != nullptr) {
2462 Method* const method = klass->find_method_impl(name,
2463 signature,
2464 overpass_local_mode,
2465 StaticLookupMode::find,
2466 private_mode);
2467 if (method != nullptr) {
2468 return method;
2469 }
2470 if (name == vmSymbols::object_initializer_name()) {
2471 break; // <init> is never inherited
2472 }
2473 klass = klass->super();
2474 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2475 }
2476 return nullptr;
2477 }
2478
2479 #ifdef ASSERT
2480 // search through class hierarchy and return true if this class or
2481 // one of the superclasses was redefined
2482 bool InstanceKlass::has_redefined_this_or_super() const {
2483 const InstanceKlass* klass = this;
2484 while (klass != nullptr) {
2485 if (klass->has_been_redefined()) {
2486 return true;
2487 }
2488 klass = klass->super();
2489 }
2490 return false;
2491 }
2492 #endif
2493
2494 // lookup a method in the default methods list then in all transitive interfaces
2495 // Do NOT return private or static methods
2496 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2497 Symbol* signature) const {
2498 Method* m = nullptr;
2499 if (default_methods() != nullptr) {
2500 m = find_method(default_methods(), name, signature);
2501 }
2502 // Look up interfaces
2503 if (m == nullptr) {
2504 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2505 }
2506 return m;
2507 }
2508
2509 // lookup a method in all the interfaces that this class implements
2510 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2511 // They should only be found in the initial InterfaceMethodRef
2512 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2513 Symbol* signature,
2514 DefaultsLookupMode defaults_mode) const {
2515 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2516 int num_ifs = all_ifs->length();
2517 InstanceKlass *ik = nullptr;
2518 for (int i = 0; i < num_ifs; i++) {
2519 ik = all_ifs->at(i);
2520 Method* m = ik->lookup_method(name, signature);
2521 if (m != nullptr && m->is_public() && !m->is_static() &&
2522 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2523 return m;
2524 }
2525 }
2526 return nullptr;
2527 }
2528
2529 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2530 :_st(st), _verbose(verbose) {
2531 ResourceMark rm;
2532 _st->print("%-18s ", "KlassAddr");
2533 _st->print("%-4s ", "Size");
2534 _st->print("%-20s ", "State");
2535 _st->print("%-7s ", "Flags");
2536 _st->print("%-5s ", "ClassName");
2537 _st->cr();
2538 }
2539
2540 void PrintClassClosure::do_klass(Klass* k) {
2541 ResourceMark rm;
2542 // klass pointer
2543 _st->print(PTR_FORMAT " ", p2i(k));
2544 // klass size
2545 _st->print("%4d ", k->size());
2546 // initialization state
2547 if (k->is_instance_klass()) {
2548 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2549 } else {
2550 _st->print("%-20s ","");
2551 }
2552 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2553 char buf[10];
2554 int i = 0;
2555 if (k->has_finalizer()) buf[i++] = 'F';
2556 if (k->is_instance_klass()) {
2557 InstanceKlass* ik = InstanceKlass::cast(k);
2558 if (ik->has_final_method()) buf[i++] = 'f';
2559 if (ik->is_rewritten()) buf[i++] = 'W';
2560 if (ik->is_contended()) buf[i++] = 'C';
2561 if (ik->has_been_redefined()) buf[i++] = 'R';
2562 if (ik->in_aot_cache()) buf[i++] = 'S';
2563 }
2564 buf[i++] = '\0';
2565 _st->print("%-7s ", buf);
2566 // klass name
2567 _st->print("%-5s ", k->external_name());
2568 // end
2569 _st->cr();
2570 if (_verbose) {
2571 k->print_on(_st);
2572 }
2573 }
2574
2575 /* jni_id_for for jfieldIds only */
2576 JNIid* InstanceKlass::jni_id_for(int offset) {
2577 MutexLocker ml(JfieldIdCreation_lock);
2578 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2579 if (probe == nullptr) {
2580 // Allocate new static field identifier
2581 probe = new JNIid(this, offset, jni_ids());
2582 set_jni_ids(probe);
2583 }
2584 return probe;
2585 }
2586
2587 u2 InstanceKlass::enclosing_method_data(int offset) const {
2588 const Array<jushort>* const inner_class_list = inner_classes();
2589 if (inner_class_list == nullptr) {
2590 return 0;
2591 }
2592 const int length = inner_class_list->length();
2593 if (length % inner_class_next_offset == 0) {
2594 return 0;
2595 }
2596 const int index = length - enclosing_method_attribute_size;
2597 assert(offset < enclosing_method_attribute_size, "invalid offset");
2598 return inner_class_list->at(index + offset);
2599 }
2600
2601 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2602 u2 method_index) {
2603 Array<jushort>* inner_class_list = inner_classes();
2604 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2605 int length = inner_class_list->length();
2606 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2607 int index = length - enclosing_method_attribute_size;
2608 inner_class_list->at_put(
2609 index + enclosing_method_class_index_offset, class_index);
2610 inner_class_list->at_put(
2611 index + enclosing_method_method_index_offset, method_index);
2612 }
2613 }
2614
2615 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2616 if (method->is_old() && !method->is_obsolete()) {
2617 // If the method passed in is old (but not obsolete), use the current version.
2618 method = method_with_idnum((int)idnum);
2619 assert(method != nullptr, "old and but not obsolete, so should exist");
2620 }
2621 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2622 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2623 return new_id;
2624 }
2625
2626 // Allocate the jmethodID cache.
2627 static jmethodID* create_jmethod_id_cache(size_t size) {
2628 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2629 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2630 // cache size is stored in element[0], other elements offset by one
2631 jmeths[0] = (jmethodID)size;
2632 return jmeths;
2633 }
2634
2635 // When reading outside a lock, use this.
2636 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2637 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2638 }
2639
2640 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2641 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2642 }
2643
2644 // Lookup or create a jmethodID.
2645 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2646 int idnum = method->method_idnum();
2647 jmethodID* jmeths = methods_jmethod_ids_acquire();
2648
2649 // We use a double-check locking idiom here because this cache is
2650 // performance sensitive. In the normal system, this cache only
2651 // transitions from null to non-null which is safe because we use
2652 // release_set_methods_jmethod_ids() to advertise the new cache.
2653 // A partially constructed cache should never be seen by a racing
2654 // thread. We also use release_store() to save a new jmethodID
2655 // in the cache so a partially constructed jmethodID should never be
2656 // seen either. Cache reads of existing jmethodIDs proceed without a
2657 // lock, but cache writes of a new jmethodID requires uniqueness and
2658 // creation of the cache itself requires no leaks so a lock is
2659 // acquired in those two cases.
2660 //
2661 // If the RedefineClasses() API has been used, then this cache grows
2662 // in the redefinition safepoint.
2663
2664 if (jmeths == nullptr) {
2665 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2666 jmeths = _methods_jmethod_ids;
2667 // Still null?
2668 if (jmeths == nullptr) {
2669 size_t size = idnum_allocated_count();
2670 assert(size > (size_t)idnum, "should already have space");
2671 jmeths = create_jmethod_id_cache(size);
2672 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2673
2674 // publish jmeths
2675 release_set_methods_jmethod_ids(jmeths);
2676 return new_id;
2677 }
2678 }
2679
2680 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2681 if (id == nullptr) {
2682 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2683 id = jmeths[idnum + 1];
2684 // Still null?
2685 if (id == nullptr) {
2686 return update_jmethod_id(jmeths, method, idnum);
2687 }
2688 }
2689 return id;
2690 }
2691
2692 void InstanceKlass::update_methods_jmethod_cache() {
2693 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2694 jmethodID* cache = _methods_jmethod_ids;
2695 if (cache != nullptr) {
2696 size_t size = idnum_allocated_count();
2697 size_t old_size = (size_t)cache[0];
2698 if (old_size < size + 1) {
2699 // Allocate a larger one and copy entries to the new one.
2700 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2701 jmethodID* new_cache = create_jmethod_id_cache(size);
2702
2703 for (int i = 1; i <= (int)old_size; i++) {
2704 new_cache[i] = cache[i];
2705 }
2706 _methods_jmethod_ids = new_cache;
2707 FREE_C_HEAP_ARRAY(jmethodID, cache);
2708 }
2709 }
2710 }
2711
2712 // Make a jmethodID for all methods in this class. This makes getting all method
2713 // ids much, much faster with classes with more than 8
2714 // methods, and has a *substantial* effect on performance with jvmti
2715 // code that loads all jmethodIDs for all classes.
2716 void InstanceKlass::make_methods_jmethod_ids() {
2717 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2718 jmethodID* jmeths = _methods_jmethod_ids;
2719 if (jmeths == nullptr) {
2720 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2721 release_set_methods_jmethod_ids(jmeths);
2722 }
2723
2724 int length = methods()->length();
2725 for (int index = 0; index < length; index++) {
2726 Method* m = methods()->at(index);
2727 int idnum = m->method_idnum();
2728 assert(!m->is_old(), "should not have old methods or I'm confused");
2729 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2730 if (!m->is_overpass() && // skip overpasses
2731 id == nullptr) {
2732 id = Method::make_jmethod_id(class_loader_data(), m);
2733 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2734 }
2735 }
2736 }
2737
2738 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2739 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2740 int idnum = method->method_idnum();
2741 jmethodID* jmeths = methods_jmethod_ids_acquire();
2742 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2743 }
2744
2745 inline DependencyContext InstanceKlass::dependencies() {
2746 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2747 return dep_context;
2748 }
2749
2750 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2751 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2752 }
2753
2754 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2755 assert_lock_strong(CodeCache_lock);
2756 dependencies().add_dependent_nmethod(nm);
2757 }
2758
2759 void InstanceKlass::clean_dependency_context() {
2760 dependencies().clean_unloading_dependents();
2761 }
2762
2763 #ifndef PRODUCT
2764 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2765 dependencies().print_dependent_nmethods(verbose);
2766 }
2767
2768 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2769 return dependencies().is_dependent_nmethod(nm);
2770 }
2771 #endif //PRODUCT
2772
2773 void InstanceKlass::clean_weak_instanceklass_links() {
2774 clean_implementors_list();
2775 clean_method_data();
2776 }
2777
2778 void InstanceKlass::clean_implementors_list() {
2779 assert(is_loader_alive(), "this klass should be live");
2780 if (is_interface()) {
2781 assert (ClassUnloading, "only called for ClassUnloading");
2782 for (;;) {
2783 // Use load_acquire due to competing with inserts
2784 InstanceKlass* volatile* iklass = adr_implementor();
2785 assert(iklass != nullptr, "Klass must not be null");
2786 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2787 if (impl != nullptr && !impl->is_loader_alive()) {
2788 // null this field, might be an unloaded instance klass or null
2789 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2790 // Successfully unlinking implementor.
2791 if (log_is_enabled(Trace, class, unload)) {
2792 ResourceMark rm;
2793 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2794 }
2795 return;
2796 }
2797 } else {
2798 return;
2799 }
2800 }
2801 }
2802 }
2803
2804 void InstanceKlass::clean_method_data() {
2805 for (int m = 0; m < methods()->length(); m++) {
2806 MethodData* mdo = methods()->at(m)->method_data();
2807 if (mdo != nullptr) {
2808 mdo->clean_method_data(/*always_clean*/false);
2809 }
2810 }
2811 }
2812
2813 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2814 Klass::metaspace_pointers_do(it);
2815
2816 if (log_is_enabled(Trace, aot)) {
2817 ResourceMark rm;
2818 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2819 }
2820
2821 it->push(&_annotations);
2822 it->push((Klass**)&_array_klasses);
2823 if (!is_rewritten()) {
2824 it->push(&_constants, MetaspaceClosure::_writable);
2825 } else {
2826 it->push(&_constants);
2827 }
2828 it->push(&_inner_classes);
2829 #if INCLUDE_JVMTI
2830 it->push(&_previous_versions);
2831 #endif
2832 #if INCLUDE_CDS
2833 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2834 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2835 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2836 // The length check on the _methods is necessary because classes which don't have any
2837 // methods share the Universe::_the_empty_method_array which is in the RO region.
2838 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2839 // To handle jsr bytecode, new Method* maybe stored into _methods
2840 it->push(&_methods, MetaspaceClosure::_writable);
2841 } else {
2842 #endif
2843 it->push(&_methods);
2844 #if INCLUDE_CDS
2845 }
2846 #endif
2847 it->push(&_default_methods);
2848 it->push(&_local_interfaces);
2849 it->push(&_transitive_interfaces);
2850 it->push(&_method_ordering);
2851 if (!is_rewritten()) {
2852 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2853 } else {
2854 it->push(&_default_vtable_indices);
2855 }
2856
2857 it->push(&_fieldinfo_stream);
2858 it->push(&_fieldinfo_search_table);
2859 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2860 it->push(&_fields_status, MetaspaceClosure::_writable);
2861
2862 if (itable_length() > 0) {
2863 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2864 int method_table_offset_in_words = ioe->offset()/wordSize;
2865 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2866
2867 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2868 / itableOffsetEntry::size();
2869
2870 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2871 if (ioe->interface_klass() != nullptr) {
2872 it->push(ioe->interface_klass_addr());
2873 itableMethodEntry* ime = ioe->first_method_entry(this);
2874 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2875 for (int index = 0; index < n; index ++) {
2876 it->push(ime[index].method_addr());
2877 }
2878 }
2879 }
2880 }
2881
2882 it->push(&_nest_host);
2883 it->push(&_nest_members);
2884 it->push(&_permitted_subclasses);
2885 it->push(&_loadable_descriptors);
2886 it->push(&_record_components);
2887 it->push(&_inline_layout_info_array, MetaspaceClosure::_writable);
2888 }
2889
2890 #if INCLUDE_CDS
2891 void InstanceKlass::remove_unshareable_info() {
2892
2893 if (is_linked()) {
2894 assert(can_be_verified_at_dumptime(), "must be");
2895 // Remember this so we can avoid walking the hierarchy at runtime.
2896 set_verified_at_dump_time();
2897 }
2898
2899 _misc_flags.set_has_init_deps_processed(false);
2900
2901 Klass::remove_unshareable_info();
2902
2903 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2904 // Classes are attempted to link during dumping and may fail,
2905 // but these classes are still in the dictionary and class list in CLD.
2906 // If the class has failed verification, there is nothing else to remove.
2907 return;
2908 }
2909
2910 // Reset to the 'allocated' state to prevent any premature accessing to
2911 // a shared class at runtime while the class is still being loaded and
2912 // restored. A class' init_state is set to 'loaded' at runtime when it's
2913 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2914 _init_state = allocated;
2915
2916 { // Otherwise this needs to take out the Compile_lock.
2917 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2918 init_implementor();
2919 }
2920
2921 // Call remove_unshareable_info() on other objects that belong to this class, except
2922 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2923 // ArchiveBuilder::make_klasses_shareable(),
2924
2925 for (int i = 0; i < methods()->length(); i++) {
2926 Method* m = methods()->at(i);
2927 m->remove_unshareable_info();
2928 }
2929
2930 // do array classes also.
2931 if (array_klasses() != nullptr) {
2932 array_klasses()->remove_unshareable_info();
2933 }
2934
2935 // These are not allocated from metaspace. They are safe to set to nullptr.
2936 _source_debug_extension = nullptr;
2937 _dep_context = nullptr;
2938 _osr_nmethods_head = nullptr;
2939 #if INCLUDE_JVMTI
2940 _breakpoints = nullptr;
2941 _previous_versions = nullptr;
2942 _cached_class_file = nullptr;
2943 _jvmti_cached_class_field_map = nullptr;
2944 #endif
2945
2946 _init_thread = nullptr;
2947 _methods_jmethod_ids = nullptr;
2948 _jni_ids = nullptr;
2949 _oop_map_cache = nullptr;
2950 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2951 // keep _nest_host
2952 } else {
2953 // clear _nest_host to ensure re-load at runtime
2954 _nest_host = nullptr;
2955 }
2956 init_shared_package_entry();
2957 _dep_context_last_cleaned = 0;
2958 DEBUG_ONLY(_shared_class_load_count = 0);
2959
2960 remove_unshareable_flags();
2961
2962 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2963 }
2964
2965 void InstanceKlass::remove_unshareable_flags() {
2966 // clear all the flags/stats that shouldn't be in the archived version
2967 assert(!is_scratch_class(), "must be");
2968 assert(!has_been_redefined(), "must be");
2969 #if INCLUDE_JVMTI
2970 set_is_being_redefined(false);
2971 #endif
2972 set_has_resolved_methods(false);
2973 }
2974
2975 void InstanceKlass::remove_java_mirror() {
2976 Klass::remove_java_mirror();
2977
2978 // do array classes also.
2979 if (array_klasses() != nullptr) {
2980 array_klasses()->remove_java_mirror();
2981 }
2982 }
2983
2984 void InstanceKlass::init_shared_package_entry() {
2985 assert(CDSConfig::is_dumping_archive(), "must be");
2986 #if !INCLUDE_CDS_JAVA_HEAP
2987 _package_entry = nullptr;
2988 #else
2989 if (CDSConfig::is_dumping_full_module_graph()) {
2990 if (defined_by_other_loaders()) {
2991 _package_entry = nullptr;
2992 } else {
2993 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2994 }
2995 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2996 CDSConfig::is_using_full_module_graph() &&
2997 AOTMetaspace::in_aot_cache(_package_entry)) {
2998 // _package_entry is an archived package in the base archive. Leave it as is.
2999 } else {
3000 _package_entry = nullptr;
3001 }
3002 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
3003 #endif
3004 }
3005
3006 void InstanceKlass::compute_has_loops_flag_for_methods() {
3007 Array<Method*>* methods = this->methods();
3008 for (int index = 0; index < methods->length(); ++index) {
3009 Method* m = methods->at(index);
3010 if (!m->is_overpass()) { // work around JDK-8305771
3011 m->compute_has_loops_flag();
3012 }
3013 }
3014 }
3015
3016 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
3017 PackageEntry* pkg_entry, TRAPS) {
3018 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
3019 // before the InstanceKlass is added to the SystemDictionary. Make
3020 // sure the current state is <loaded.
3021 assert(!is_loaded(), "invalid init state");
3022 assert(!shared_loading_failed(), "Must not try to load failed class again");
3023 set_package(loader_data, pkg_entry, CHECK);
3024 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
3025
3026 if (is_inline_klass()) {
3027 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
3028 }
3029
3030 Array<Method*>* methods = this->methods();
3031 int num_methods = methods->length();
3032 for (int index = 0; index < num_methods; ++index) {
3033 methods->at(index)->restore_unshareable_info(CHECK);
3034 }
3035 #if INCLUDE_JVMTI
3036 if (JvmtiExport::has_redefined_a_class()) {
3037 // Reinitialize vtable because RedefineClasses may have changed some
3038 // entries in this vtable for super classes so the CDS vtable might
3039 // point to old or obsolete entries. RedefineClasses doesn't fix up
3040 // vtables in the shared system dictionary, only the main one.
3041 // It also redefines the itable too so fix that too.
3042 // First fix any default methods that point to a super class that may
3043 // have been redefined.
3044 bool trace_name_printed = false;
3045 adjust_default_methods(&trace_name_printed);
3046 if (verified_at_dump_time()) {
3047 // Initialize vtable and itable for classes which can be verified at dump time.
3048 // Unlinked classes such as old classes with major version < 50 cannot be verified
3049 // at dump time.
3050 vtable().initialize_vtable();
3051 itable().initialize_itable();
3052 }
3053 }
3054 #endif // INCLUDE_JVMTI
3055
3056 // restore constant pool resolved references
3057 constants()->restore_unshareable_info(CHECK);
3058
3059 if (array_klasses() != nullptr) {
3060 // To get a consistent list of classes we need MultiArray_lock to ensure
3061 // array classes aren't observed while they are being restored.
3062 RecursiveLocker rl(MultiArray_lock, THREAD);
3063 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
3064 // Array classes have null protection domain.
3065 // --> see ArrayKlass::complete_create_array_klass()
3066 if (class_loader_data() == nullptr) {
3067 ResourceMark rm(THREAD);
3068 log_debug(cds)(" loader_data %s ", loader_data == nullptr ? "nullptr" : "non null");
3069 log_debug(cds)(" this %s array_klasses %s ", this->name()->as_C_string(), array_klasses()->name()->as_C_string());
3070 }
3071 assert(!array_klasses()->is_refined_objArray_klass(), "must be non-refined objarrayklass");
3072 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3073 }
3074
3075 // Initialize @ValueBased class annotation if not already set in the archived klass.
3076 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
3077 set_is_value_based();
3078 }
3079
3080 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
3081 }
3082
3083 bool InstanceKlass::can_be_verified_at_dumptime() const {
3084 if (AOTMetaspace::in_aot_cache(this)) {
3085 // This is a class that was dumped into the base archive, so we know
3086 // it was verified at dump time.
3087 return true;
3088 }
3089
3090 if (CDSConfig::is_preserving_verification_constraints()) {
3091 return true;
3092 }
3093
3094 if (CDSConfig::is_old_class_for_verifier(this)) {
3095 // The old verifier does not save verification constraints, so at run time
3096 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
3097 return false;
3098 }
3099 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
3100 return false;
3101 }
3102 Array<InstanceKlass*>* interfaces = local_interfaces();
3103 int len = interfaces->length();
3104 for (int i = 0; i < len; i++) {
3105 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3106 return false;
3107 }
3108 }
3109 return true;
3110 }
3111
3112 #endif // INCLUDE_CDS
3113
3114 #if INCLUDE_JVMTI
3115 static void clear_all_breakpoints(Method* m) {
3116 m->clear_all_breakpoints();
3117 }
3118 #endif
3119
3120 void InstanceKlass::unload_class(InstanceKlass* ik) {
3121
3122 if (ik->is_scratch_class()) {
3123 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
3124 return;
3125 }
3126 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
3127
3128 // Release dependencies.
3129 ik->dependencies().remove_all_dependents();
3130
3131 // notify the debugger
3132 if (JvmtiExport::should_post_class_unload()) {
3133 JvmtiExport::post_class_unload(ik);
3134 }
3135
3136 // notify ClassLoadingService of class unload
3137 ClassLoadingService::notify_class_unloaded(ik);
3138
3139 SystemDictionaryShared::handle_class_unloading(ik);
3140
3141 if (log_is_enabled(Info, class, unload)) {
3142 ResourceMark rm;
3143 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3144 }
3145
3146 Events::log_class_unloading(Thread::current(), ik);
3147
3148 #if INCLUDE_JFR
3149 assert(ik != nullptr, "invariant");
3150 EventClassUnload event;
3151 event.set_unloadedClass(ik);
3152 event.set_definingClassLoader(ik->class_loader_data());
3153 event.commit();
3154 #endif
3155 }
3156
3157 static void method_release_C_heap_structures(Method* m) {
3158 m->release_C_heap_structures();
3159 }
3160
3161 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3162 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3163 // Clean up C heap
3164 Klass::release_C_heap_structures();
3165
3166 // Deallocate and call destructors for MDO mutexes
3167 if (release_sub_metadata) {
3168 methods_do(method_release_C_heap_structures);
3169 }
3170
3171 // Deallocate oop map cache
3172 if (_oop_map_cache != nullptr) {
3173 delete _oop_map_cache;
3174 _oop_map_cache = nullptr;
3175 }
3176
3177 // Deallocate JNI identifiers for jfieldIDs
3178 JNIid::deallocate(jni_ids());
3179 set_jni_ids(nullptr);
3180
3181 jmethodID* jmeths = _methods_jmethod_ids;
3182 if (jmeths != nullptr) {
3183 release_set_methods_jmethod_ids(nullptr);
3184 FreeHeap(jmeths);
3185 }
3186
3187 assert(_dep_context == nullptr,
3188 "dependencies should already be cleaned");
3189
3190 #if INCLUDE_JVMTI
3191 // Deallocate breakpoint records
3192 if (breakpoints() != nullptr) {
3193 methods_do(clear_all_breakpoints);
3194 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3195 }
3196
3197 // deallocate the cached class file
3198 if (_cached_class_file != nullptr) {
3199 os::free(_cached_class_file);
3200 _cached_class_file = nullptr;
3201 }
3202 #endif
3203
3204 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3205
3206 if (release_sub_metadata) {
3207 constants()->release_C_heap_structures();
3208 }
3209 }
3210
3211 // The constant pool is on stack if any of the methods are executing or
3212 // referenced by handles.
3213 bool InstanceKlass::on_stack() const {
3214 return _constants->on_stack();
3215 }
3216
3217 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3218 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3219 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3220
3221 // minor and major version numbers of class file
3222 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3223 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3224 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3225 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3226
3227 bool InstanceKlass::supports_inline_types() const {
3228 return major_version() >= Verifier::VALUE_TYPES_MAJOR_VERSION && minor_version() == Verifier::JAVA_PREVIEW_MINOR_VERSION;
3229 }
3230
3231 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3232 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3233 if (ik->constants()->version() == version) {
3234 return ik;
3235 }
3236 }
3237 return nullptr;
3238 }
3239
3240 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3241 if (array == nullptr) {
3242 _source_debug_extension = nullptr;
3243 } else {
3244 // Adding one to the attribute length in order to store a null terminator
3245 // character could cause an overflow because the attribute length is
3246 // already coded with an u4 in the classfile, but in practice, it's
3247 // unlikely to happen.
3248 assert((length+1) > length, "Overflow checking");
3249 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3250 for (int i = 0; i < length; i++) {
3251 sde[i] = array[i];
3252 }
3253 sde[length] = '\0';
3254 _source_debug_extension = sde;
3255 }
3256 }
3257
3258 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3259 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3260 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3261
3262 const char* InstanceKlass::signature_name() const {
3263 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3264 }
3265
3266 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3267 // Get the internal name as a c string
3268 const char* src = (const char*) (name()->as_C_string());
3269 const int src_length = (int)strlen(src);
3270
3271 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3272
3273 // Add L or Q as type indicator
3274 int dest_index = 0;
3275 dest[dest_index++] = c;
3276
3277 // Add the actual class name
3278 for (int src_index = 0; src_index < src_length; ) {
3279 dest[dest_index++] = src[src_index++];
3280 }
3281
3282 if (is_hidden()) { // Replace the last '+' with a '.'.
3283 for (int index = (int)src_length; index > 0; index--) {
3284 if (dest[index] == '+') {
3285 dest[index] = JVM_SIGNATURE_DOT;
3286 break;
3287 }
3288 }
3289 }
3290
3291 // Add the semicolon and the null
3292 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3293 dest[dest_index] = '\0';
3294 return dest;
3295 }
3296
3297 ModuleEntry* InstanceKlass::module() const {
3298 if (is_hidden() &&
3299 in_unnamed_package() &&
3300 class_loader_data()->has_class_mirror_holder()) {
3301 // For a non-strong hidden class defined to an unnamed package,
3302 // its (class held) CLD will not have an unnamed module created for it.
3303 // Two choices to find the correct ModuleEntry:
3304 // 1. If hidden class is within a nest, use nest host's module
3305 // 2. Find the unnamed module off from the class loader
3306 // For now option #2 is used since a nest host is not set until
3307 // after the instance class is created in jvm_lookup_define_class().
3308 if (class_loader_data()->is_boot_class_loader_data()) {
3309 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3310 } else {
3311 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3312 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3313 return java_lang_Module::module_entry(module);
3314 }
3315 }
3316
3317 // Class is in a named package
3318 if (!in_unnamed_package()) {
3319 return _package_entry->module();
3320 }
3321
3322 // Class is in an unnamed package, return its loader's unnamed module
3323 return class_loader_data()->unnamed_module();
3324 }
3325
3326 bool InstanceKlass::in_javabase_module() const {
3327 return module()->name() == vmSymbols::java_base();
3328 }
3329
3330 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3331
3332 // ensure java/ packages only loaded by boot or platform builtin loaders
3333 // not needed for shared class since CDS does not archive prohibited classes.
3334 if (!in_aot_cache()) {
3335 check_prohibited_package(name(), loader_data, CHECK);
3336 }
3337
3338 if (in_aot_cache() && _package_entry != nullptr) {
3339 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3340 // we can use the saved package
3341 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3342 return;
3343 } else {
3344 _package_entry = nullptr;
3345 }
3346 }
3347
3348 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3349 // it returns, so we need to decrement it when the current function exits.
3350 TempNewSymbol from_class_name =
3351 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3352
3353 Symbol* pkg_name;
3354 if (pkg_entry != nullptr) {
3355 pkg_name = pkg_entry->name();
3356 } else {
3357 pkg_name = from_class_name;
3358 }
3359
3360 if (pkg_name != nullptr && loader_data != nullptr) {
3361
3362 // Find in class loader's package entry table.
3363 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3364
3365 // If the package name is not found in the loader's package
3366 // entry table, it is an indication that the package has not
3367 // been defined. Consider it defined within the unnamed module.
3368 if (_package_entry == nullptr) {
3369
3370 if (!ModuleEntryTable::javabase_defined()) {
3371 // Before java.base is defined during bootstrapping, define all packages in
3372 // the java.base module. If a non-java.base package is erroneously placed
3373 // in the java.base module it will be caught later when java.base
3374 // is defined by ModuleEntryTable::verify_javabase_packages check.
3375 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3376 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3377 } else {
3378 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3379 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3380 }
3381
3382 // A package should have been successfully created
3383 DEBUG_ONLY(ResourceMark rm(THREAD));
3384 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3385 name()->as_C_string(), loader_data->loader_name_and_id());
3386 }
3387
3388 if (log_is_enabled(Debug, module)) {
3389 ResourceMark rm(THREAD);
3390 ModuleEntry* m = _package_entry->module();
3391 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3392 external_name(),
3393 pkg_name->as_C_string(),
3394 loader_data->loader_name_and_id(),
3395 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3396 }
3397 } else {
3398 ResourceMark rm(THREAD);
3399 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3400 external_name(),
3401 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3402 UNNAMED_MODULE);
3403 }
3404 }
3405
3406 // Function set_classpath_index ensures that for a non-null _package_entry
3407 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3408 // It then sets the classpath_index in the package entry record.
3409 //
3410 // The classpath_index field is used to find the entry on the boot loader class
3411 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3412 // in an unnamed module. It is also used to indicate (for all packages whose
3413 // classes are loaded by the boot loader) that at least one of the package's
3414 // classes has been loaded.
3415 void InstanceKlass::set_classpath_index(s2 path_index) {
3416 if (_package_entry != nullptr) {
3417 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3418 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3419 assert(path_index != -1, "Unexpected classpath_index");
3420 _package_entry->set_classpath_index(path_index);
3421 }
3422 }
3423
3424 // different versions of is_same_class_package
3425
3426 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3427 oop classloader1 = this->class_loader();
3428 PackageEntry* classpkg1 = this->package();
3429 if (class2->is_objArray_klass()) {
3430 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3431 }
3432
3433 oop classloader2;
3434 PackageEntry* classpkg2;
3435 if (class2->is_instance_klass()) {
3436 classloader2 = class2->class_loader();
3437 classpkg2 = class2->package();
3438 } else {
3439 assert(class2->is_typeArray_klass(), "should be type array");
3440 classloader2 = nullptr;
3441 classpkg2 = nullptr;
3442 }
3443
3444 // Same package is determined by comparing class loader
3445 // and package entries. Both must be the same. This rule
3446 // applies even to classes that are defined in the unnamed
3447 // package, they still must have the same class loader.
3448 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3449 return true;
3450 }
3451
3452 return false;
3453 }
3454
3455 // return true if this class and other_class are in the same package. Classloader
3456 // and classname information is enough to determine a class's package
3457 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3458 const Symbol* other_class_name) const {
3459 if (class_loader() != other_class_loader) {
3460 return false;
3461 }
3462 if (name()->fast_compare(other_class_name) == 0) {
3463 return true;
3464 }
3465
3466 {
3467 ResourceMark rm;
3468
3469 bool bad_class_name = false;
3470 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3471 if (bad_class_name) {
3472 return false;
3473 }
3474 // Check that package_from_class_name() returns null, not "", if there is no package.
3475 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3476
3477 const Symbol* const this_package_name =
3478 this->package() != nullptr ? this->package()->name() : nullptr;
3479
3480 if (this_package_name == nullptr || other_pkg == nullptr) {
3481 // One of the two doesn't have a package. Only return true if the other
3482 // one also doesn't have a package.
3483 return this_package_name == other_pkg;
3484 }
3485
3486 // Check if package is identical
3487 return this_package_name->fast_compare(other_pkg) == 0;
3488 }
3489 }
3490
3491 static bool is_prohibited_package_slow(Symbol* class_name) {
3492 // Caller has ResourceMark
3493 int length;
3494 jchar* unicode = class_name->as_unicode(length);
3495 return (length >= 5 &&
3496 unicode[0] == 'j' &&
3497 unicode[1] == 'a' &&
3498 unicode[2] == 'v' &&
3499 unicode[3] == 'a' &&
3500 unicode[4] == '/');
3501 }
3502
3503 // Only boot and platform class loaders can define classes in "java/" packages.
3504 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3505 ClassLoaderData* loader_data,
3506 TRAPS) {
3507 if (!loader_data->is_boot_class_loader_data() &&
3508 !loader_data->is_platform_class_loader_data() &&
3509 class_name != nullptr && class_name->utf8_length() >= 5) {
3510 ResourceMark rm(THREAD);
3511 bool prohibited;
3512 const u1* base = class_name->base();
3513 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3514 prohibited = is_prohibited_package_slow(class_name);
3515 } else {
3516 char* name = class_name->as_C_string();
3517 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3518 }
3519 if (prohibited) {
3520 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3521 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3522 char* name = pkg_name->as_C_string();
3523 const char* class_loader_name = loader_data->loader_name_and_id();
3524 StringUtils::replace_no_expand(name, "/", ".");
3525 const char* msg_text1 = "Class loader (instance of): ";
3526 const char* msg_text2 = " tried to load prohibited package name: ";
3527 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3528 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3529 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3530 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3531 }
3532 }
3533 return;
3534 }
3535
3536 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3537 constantPoolHandle i_cp(THREAD, constants());
3538 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3539 int ioff = iter.inner_class_info_index();
3540 if (ioff != 0) {
3541 // Check to see if the name matches the class we're looking for
3542 // before attempting to find the class.
3543 if (i_cp->klass_name_at_matches(this, ioff)) {
3544 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3545 if (this == inner_klass) {
3546 *ooff = iter.outer_class_info_index();
3547 *noff = iter.inner_name_index();
3548 return true;
3549 }
3550 }
3551 }
3552 }
3553 return false;
3554 }
3555
3556 void InstanceKlass::check_can_be_annotated_with_NullRestricted(InstanceKlass* type, Symbol* container_klass_name, TRAPS) {
3557 assert(type->is_instance_klass(), "Sanity check");
3558 if (type->is_identity_class()) {
3559 ResourceMark rm(THREAD);
3560 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3561 err_msg("Class %s expects class %s to be a value class, but it is an identity class",
3562 container_klass_name->as_C_string(),
3563 type->external_name()));
3564 }
3565
3566 if (type->is_abstract()) {
3567 ResourceMark rm(THREAD);
3568 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3569 err_msg("Class %s expects class %s to be concrete value type, but it is an abstract class",
3570 container_klass_name->as_C_string(),
3571 type->external_name()));
3572 }
3573 }
3574
3575 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3576 InstanceKlass* outer_klass = nullptr;
3577 *inner_is_member = false;
3578 int ooff = 0, noff = 0;
3579 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3580 if (has_inner_classes_attr) {
3581 constantPoolHandle i_cp(THREAD, constants());
3582 if (ooff != 0) {
3583 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3584 if (!ok->is_instance_klass()) {
3585 // If the outer class is not an instance klass then it cannot have
3586 // declared any inner classes.
3587 ResourceMark rm(THREAD);
3588 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3589 Exceptions::fthrow(
3590 THREAD_AND_LOCATION,
3591 vmSymbols::java_lang_IncompatibleClassChangeError(),
3592 "%s and %s disagree on InnerClasses attribute",
3593 ok->external_name(),
3594 external_name());
3595 return nullptr;
3596 }
3597 outer_klass = InstanceKlass::cast(ok);
3598 *inner_is_member = true;
3599 }
3600 if (nullptr == outer_klass) {
3601 // It may be a local class; try for that.
3602 int encl_method_class_idx = enclosing_method_class_index();
3603 if (encl_method_class_idx != 0) {
3604 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3605 outer_klass = InstanceKlass::cast(ok);
3606 *inner_is_member = false;
3607 }
3608 }
3609 }
3610
3611 // If no inner class attribute found for this class.
3612 if (nullptr == outer_klass) return nullptr;
3613
3614 // Throws an exception if outer klass has not declared k as an inner klass
3615 // We need evidence that each klass knows about the other, or else
3616 // the system could allow a spoof of an inner class to gain access rights.
3617 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3618 return outer_klass;
3619 }
3620
3621 u2 InstanceKlass::compute_modifier_flags() const {
3622 u2 access = access_flags().as_unsigned_short();
3623
3624 // But check if it happens to be member class.
3625 InnerClassesIterator iter(this);
3626 for (; !iter.done(); iter.next()) {
3627 int ioff = iter.inner_class_info_index();
3628 // Inner class attribute can be zero, skip it.
3629 // Strange but true: JVM spec. allows null inner class refs.
3630 if (ioff == 0) continue;
3631
3632 // only look at classes that are already loaded
3633 // since we are looking for the flags for our self.
3634 Symbol* inner_name = constants()->klass_name_at(ioff);
3635 if (name() == inner_name) {
3636 // This is really a member class.
3637 access = iter.inner_access_flags();
3638 break;
3639 }
3640 }
3641 return access;
3642 }
3643
3644 jint InstanceKlass::jvmti_class_status() const {
3645 jint result = 0;
3646
3647 if (is_linked()) {
3648 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3649 }
3650
3651 if (is_initialized()) {
3652 assert(is_linked(), "Class status is not consistent");
3653 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3654 }
3655 if (is_in_error_state()) {
3656 result |= JVMTI_CLASS_STATUS_ERROR;
3657 }
3658 return result;
3659 }
3660
3661 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3662 bool implements_interface; // initialized by method_at_itable_or_null
3663 Method* m = method_at_itable_or_null(holder, index,
3664 implements_interface); // out parameter
3665 if (m != nullptr) {
3666 assert(implements_interface, "sanity");
3667 return m;
3668 } else if (implements_interface) {
3669 // Throw AbstractMethodError since corresponding itable slot is empty.
3670 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3671 } else {
3672 // If the interface isn't implemented by the receiver class,
3673 // the VM should throw IncompatibleClassChangeError.
3674 ResourceMark rm(THREAD);
3675 stringStream ss;
3676 bool same_module = (module() == holder->module());
3677 ss.print("Receiver class %s does not implement "
3678 "the interface %s defining the method to be called "
3679 "(%s%s%s)",
3680 external_name(), holder->external_name(),
3681 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3682 (same_module) ? "" : "; ",
3683 (same_module) ? "" : holder->class_in_module_of_loader());
3684 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3685 }
3686 }
3687
3688 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3689 klassItable itable(this);
3690 for (int i = 0; i < itable.size_offset_table(); i++) {
3691 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3692 if (offset_entry->interface_klass() == holder) {
3693 implements_interface = true;
3694 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3695 Method* m = ime[index].method();
3696 return m;
3697 }
3698 }
3699 implements_interface = false;
3700 return nullptr; // offset entry not found
3701 }
3702
3703 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3704 assert(is_linked(), "required");
3705 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3706 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3707
3708 int vtable_index = Method::invalid_vtable_index;
3709 Symbol* name = intf_method->name();
3710 Symbol* signature = intf_method->signature();
3711
3712 // First check in default method array
3713 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3714 int index = find_method_index(default_methods(),
3715 name, signature,
3716 Klass::OverpassLookupMode::find,
3717 Klass::StaticLookupMode::find,
3718 Klass::PrivateLookupMode::find);
3719 if (index >= 0) {
3720 vtable_index = default_vtable_indices()->at(index);
3721 }
3722 }
3723 if (vtable_index == Method::invalid_vtable_index) {
3724 // get vtable_index for miranda methods
3725 klassVtable vt = vtable();
3726 vtable_index = vt.index_of_miranda(name, signature);
3727 }
3728 return vtable_index;
3729 }
3730
3731 #if INCLUDE_JVMTI
3732 // update default_methods for redefineclasses for methods that are
3733 // not yet in the vtable due to concurrent subclass define and superinterface
3734 // redefinition
3735 // Note: those in the vtable, should have been updated via adjust_method_entries
3736 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3737 // search the default_methods for uses of either obsolete or EMCP methods
3738 if (default_methods() != nullptr) {
3739 for (int index = 0; index < default_methods()->length(); index ++) {
3740 Method* old_method = default_methods()->at(index);
3741 if (old_method == nullptr || !old_method->is_old()) {
3742 continue; // skip uninteresting entries
3743 }
3744 assert(!old_method->is_deleted(), "default methods may not be deleted");
3745 Method* new_method = old_method->get_new_method();
3746 default_methods()->at_put(index, new_method);
3747
3748 if (log_is_enabled(Info, redefine, class, update)) {
3749 ResourceMark rm;
3750 if (!(*trace_name_printed)) {
3751 log_info(redefine, class, update)
3752 ("adjust: klassname=%s default methods from name=%s",
3753 external_name(), old_method->method_holder()->external_name());
3754 *trace_name_printed = true;
3755 }
3756 log_debug(redefine, class, update, vtables)
3757 ("default method update: %s(%s) ",
3758 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3759 }
3760 }
3761 }
3762 }
3763 #endif // INCLUDE_JVMTI
3764
3765 // On-stack replacement stuff
3766 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3767 assert_lock_strong(NMethodState_lock);
3768 #ifndef PRODUCT
3769 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3770 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3771 "redundant OSR recompilation detected. memory leak in CodeCache!");
3772 #endif
3773 // only one compilation can be active
3774 assert(n->is_osr_method(), "wrong kind of nmethod");
3775 n->set_osr_link(osr_nmethods_head());
3776 set_osr_nmethods_head(n);
3777 // Raise the highest osr level if necessary
3778 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3779
3780 // Get rid of the osr methods for the same bci that have lower levels.
3781 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3782 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3783 if (inv != nullptr && inv->is_in_use()) {
3784 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3785 }
3786 }
3787 }
3788
3789 // Remove osr nmethod from the list. Return true if found and removed.
3790 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3791 // This is a short non-blocking critical region, so the no safepoint check is ok.
3792 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3793 assert(n->is_osr_method(), "wrong kind of nmethod");
3794 nmethod* last = nullptr;
3795 nmethod* cur = osr_nmethods_head();
3796 int max_level = CompLevel_none; // Find the max comp level excluding n
3797 Method* m = n->method();
3798 // Search for match
3799 bool found = false;
3800 while(cur != nullptr && cur != n) {
3801 if (m == cur->method()) {
3802 // Find max level before n
3803 max_level = MAX2(max_level, cur->comp_level());
3804 }
3805 last = cur;
3806 cur = cur->osr_link();
3807 }
3808 nmethod* next = nullptr;
3809 if (cur == n) {
3810 found = true;
3811 next = cur->osr_link();
3812 if (last == nullptr) {
3813 // Remove first element
3814 set_osr_nmethods_head(next);
3815 } else {
3816 last->set_osr_link(next);
3817 }
3818 }
3819 n->set_osr_link(nullptr);
3820 cur = next;
3821 while (cur != nullptr) {
3822 // Find max level after n
3823 if (m == cur->method()) {
3824 max_level = MAX2(max_level, cur->comp_level());
3825 }
3826 cur = cur->osr_link();
3827 }
3828 m->set_highest_osr_comp_level(max_level);
3829 return found;
3830 }
3831
3832 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3833 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3834 nmethod* osr = osr_nmethods_head();
3835 int found = 0;
3836 while (osr != nullptr) {
3837 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3838 if (osr->method() == m) {
3839 deopt_scope->mark(osr);
3840 found++;
3841 }
3842 osr = osr->osr_link();
3843 }
3844 return found;
3845 }
3846
3847 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3848 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3849 nmethod* osr = osr_nmethods_head();
3850 nmethod* best = nullptr;
3851 while (osr != nullptr) {
3852 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3853 // There can be a time when a c1 osr method exists but we are waiting
3854 // for a c2 version. When c2 completes its osr nmethod we will trash
3855 // the c1 version and only be able to find the c2 version. However
3856 // while we overflow in the c1 code at back branches we don't want to
3857 // try and switch to the same code as we are already running
3858
3859 if (osr->method() == m &&
3860 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3861 if (match_level) {
3862 if (osr->comp_level() == comp_level) {
3863 // Found a match - return it.
3864 return osr;
3865 }
3866 } else {
3867 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3868 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3869 // Found the best possible - return it.
3870 return osr;
3871 }
3872 best = osr;
3873 }
3874 }
3875 }
3876 osr = osr->osr_link();
3877 }
3878
3879 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3880 if (best != nullptr && best->comp_level() >= comp_level) {
3881 return best;
3882 }
3883 return nullptr;
3884 }
3885
3886 // -----------------------------------------------------------------------------------------------------
3887 // Printing
3888
3889 #define BULLET " - "
3890
3891 static const char* state_names[] = {
3892 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3893 };
3894
3895 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3896 ResourceMark rm;
3897 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3898 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3899 for (int i = 0; i < len; i++) {
3900 intptr_t e = start[i];
3901 st->print("%d : " INTPTR_FORMAT, i, e);
3902 if (forward_refs[i] != 0) {
3903 int from = forward_refs[i];
3904 int off = (int) start[from];
3905 st->print(" (offset %d <= [%d])", off, from);
3906 }
3907 if (MetaspaceObj::is_valid((Metadata*)e)) {
3908 st->print(" ");
3909 ((Metadata*)e)->print_value_on(st);
3910 } else if (self != nullptr && e > 0 && e < 0x10000) {
3911 address location = self + e;
3912 int index = (int)((intptr_t*)location - start);
3913 st->print(" (offset %d => [%d])", (int)e, index);
3914 if (index >= 0 && index < len)
3915 forward_refs[index] = i;
3916 }
3917 st->cr();
3918 }
3919 }
3920
3921 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3922 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3923 }
3924
3925 template<typename T>
3926 static void print_array_on(outputStream* st, Array<T>* array) {
3927 if (array == nullptr) { st->print_cr("nullptr"); return; }
3928 array->print_value_on(st); st->cr();
3929 if (Verbose || WizardMode) {
3930 for (int i = 0; i < array->length(); i++) {
3931 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3932 }
3933 }
3934 }
3935
3936 static void print_array_on(outputStream* st, Array<int>* array) {
3937 if (array == nullptr) { st->print_cr("nullptr"); return; }
3938 array->print_value_on(st); st->cr();
3939 if (Verbose || WizardMode) {
3940 for (int i = 0; i < array->length(); i++) {
3941 st->print("%d : %d", i, array->at(i)); st->cr();
3942 }
3943 }
3944 }
3945
3946 const char* InstanceKlass::init_state_name() const {
3947 return state_names[init_state()];
3948 }
3949
3950 void InstanceKlass::print_on(outputStream* st) const {
3951 assert(is_klass(), "must be klass");
3952 Klass::print_on(st);
3953
3954 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3955 st->print(BULLET"klass size: %d", size()); st->cr();
3956 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3957 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3958 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3959 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3960 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3961 st->print(BULLET"sub: ");
3962 Klass* sub = subklass();
3963 int n;
3964 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3965 if (n < MaxSubklassPrintSize) {
3966 sub->print_value_on(st);
3967 st->print(" ");
3968 }
3969 }
3970 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3971 st->cr();
3972
3973 if (is_interface()) {
3974 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3975 if (nof_implementors() == 1) {
3976 st->print_cr(BULLET"implementor: ");
3977 st->print(" ");
3978 implementor()->print_value_on(st);
3979 st->cr();
3980 }
3981 }
3982
3983 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3984 st->print(BULLET"methods: "); print_array_on(st, methods());
3985 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3986 if (default_methods() != nullptr) {
3987 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3988 }
3989 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3990 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3991 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3992
3993 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3994
3995 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3996 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3997
3998 if (secondary_supers() != nullptr) {
3999 if (Verbose) {
4000 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
4001 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
4002 for (int i = 0; i < _secondary_supers->length(); i++) {
4003 ResourceMark rm; // for external_name()
4004 Klass* secondary_super = _secondary_supers->at(i);
4005 st->print(BULLET"%2d:", i);
4006 if (is_hashed) {
4007 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
4008 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
4009 st->print(" dist:%02d:", distance);
4010 }
4011 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
4012 }
4013 }
4014 }
4015 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
4016
4017 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
4018 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
4019 if (source_debug_extension() != nullptr) {
4020 st->print(BULLET"source debug extension: ");
4021 st->print("%s", source_debug_extension());
4022 st->cr();
4023 }
4024 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
4025 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
4026 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
4027 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
4028 {
4029 bool have_pv = false;
4030 // previous versions are linked together through the InstanceKlass
4031 for (InstanceKlass* pv_node = previous_versions();
4032 pv_node != nullptr;
4033 pv_node = pv_node->previous_versions()) {
4034 if (!have_pv)
4035 st->print(BULLET"previous version: ");
4036 have_pv = true;
4037 pv_node->constants()->print_value_on(st);
4038 }
4039 if (have_pv) st->cr();
4040 }
4041
4042 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
4043 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
4044 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
4045 print_on_maybe_null(st, BULLET"record components: ", record_components());
4046 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
4047 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
4048 if (java_mirror() != nullptr) {
4049 st->print(BULLET"java mirror: ");
4050 java_mirror()->print_value_on(st);
4051 st->cr();
4052 } else {
4053 st->print_cr(BULLET"java mirror: null");
4054 }
4055 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
4056 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
4057 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
4058 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
4059 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
4060
4061 FieldPrinter print_static_field(st);
4062 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
4063 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
4064 FieldPrinter print_nonstatic_field(st);
4065 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
4066 ik->print_nonstatic_fields(&print_nonstatic_field);
4067
4068 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
4069 OopMapBlock* map = start_of_nonstatic_oop_maps();
4070 OopMapBlock* end_map = map + nonstatic_oop_map_count();
4071 while (map < end_map) {
4072 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
4073 map++;
4074 }
4075 st->cr();
4076
4077 if (fieldinfo_search_table() != nullptr) {
4078 st->print_cr(BULLET"---- field info search table:");
4079 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
4080 }
4081 }
4082
4083 void InstanceKlass::print_value_on(outputStream* st) const {
4084 assert(is_klass(), "must be klass");
4085 if (Verbose || WizardMode) access_flags().print_on(st);
4086 name()->print_value_on(st);
4087 }
4088
4089 void FieldPrinter::do_field(fieldDescriptor* fd) {
4090 for (int i = 0; i < _indent; i++) _st->print(" ");
4091 _st->print(BULLET);
4092 if (_obj == nullptr) {
4093 fd->print_on(_st, _base_offset);
4094 _st->cr();
4095 } else {
4096 fd->print_on_for(_st, _obj, _indent, _base_offset);
4097 if (!fd->field_flags().is_flat()) _st->cr();
4098 }
4099 }
4100
4101
4102 void InstanceKlass::oop_print_on(oop obj, outputStream* st, int indent, int base_offset) {
4103 Klass::oop_print_on(obj, st);
4104
4105 if (this == vmClasses::String_klass()) {
4106 typeArrayOop value = java_lang_String::value(obj);
4107 juint length = java_lang_String::length(obj);
4108 if (value != nullptr &&
4109 value->is_typeArray() &&
4110 length <= (juint) value->length()) {
4111 st->print(BULLET"string: ");
4112 java_lang_String::print(obj, st);
4113 st->cr();
4114 }
4115 }
4116
4117 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
4118 FieldPrinter print_field(st, obj, indent, base_offset);
4119 print_nonstatic_fields(&print_field);
4120
4121 if (this == vmClasses::Class_klass()) {
4122 st->print(BULLET"signature: ");
4123 java_lang_Class::print_signature(obj, st);
4124 st->cr();
4125 Klass* real_klass = java_lang_Class::as_Klass(obj);
4126 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4127 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4128 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4129 }
4130 } else if (this == vmClasses::MethodType_klass()) {
4131 st->print(BULLET"signature: ");
4132 java_lang_invoke_MethodType::print_signature(obj, st);
4133 st->cr();
4134 }
4135 }
4136
4137 #ifndef PRODUCT
4138
4139 bool InstanceKlass::verify_itable_index(int i) {
4140 int method_count = klassItable::method_count_for_interface(this);
4141 assert(i >= 0 && i < method_count, "index out of bounds");
4142 return true;
4143 }
4144
4145 #endif //PRODUCT
4146
4147 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4148 st->print("a ");
4149 name()->print_value_on(st);
4150 obj->print_address_on(st);
4151 if (this == vmClasses::String_klass()
4152 && java_lang_String::value(obj) != nullptr) {
4153 ResourceMark rm;
4154 int len = java_lang_String::length(obj);
4155 int plen = (len < 24 ? len : 12);
4156 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4157 st->print(" = \"%s\"", str);
4158 if (len > plen)
4159 st->print("...[%d]", len);
4160 } else if (this == vmClasses::Class_klass()) {
4161 Klass* k = java_lang_Class::as_Klass(obj);
4162 st->print(" = ");
4163 if (k != nullptr) {
4164 k->print_value_on(st);
4165 } else {
4166 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4167 st->print("%s", tname ? tname : "type?");
4168 }
4169 } else if (this == vmClasses::MethodType_klass()) {
4170 st->print(" = ");
4171 java_lang_invoke_MethodType::print_signature(obj, st);
4172 } else if (java_lang_boxing_object::is_instance(obj)) {
4173 st->print(" = ");
4174 java_lang_boxing_object::print(obj, st);
4175 } else if (this == vmClasses::LambdaForm_klass()) {
4176 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4177 if (vmentry != nullptr) {
4178 st->print(" => ");
4179 vmentry->print_value_on(st);
4180 }
4181 } else if (this == vmClasses::MemberName_klass()) {
4182 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4183 if (vmtarget != nullptr) {
4184 st->print(" = ");
4185 vmtarget->print_value_on(st);
4186 } else {
4187 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4188 oop name = java_lang_invoke_MemberName::name(obj);
4189 if (clazz != nullptr) {
4190 clazz->print_value_on(st);
4191 } else {
4192 st->print("null");
4193 }
4194 st->print(".");
4195 if (name != nullptr) {
4196 name->print_value_on(st);
4197 } else {
4198 st->print("null");
4199 }
4200 }
4201 }
4202 }
4203
4204 const char* InstanceKlass::internal_name() const {
4205 return external_name();
4206 }
4207
4208 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4209 const ModuleEntry* module_entry,
4210 const ClassFileStream* cfs) const {
4211
4212 if (ClassListWriter::is_enabled()) {
4213 ClassListWriter::write(this, cfs);
4214 }
4215
4216 print_class_load_helper(loader_data, module_entry, cfs);
4217 print_class_load_cause_logging();
4218 }
4219
4220 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4221 const ModuleEntry* module_entry,
4222 const ClassFileStream* cfs) const {
4223
4224 if (!log_is_enabled(Info, class, load)) {
4225 return;
4226 }
4227
4228 ResourceMark rm;
4229 LogMessage(class, load) msg;
4230 stringStream info_stream;
4231
4232 // Name and class hierarchy info
4233 info_stream.print("%s", external_name());
4234
4235 // Source
4236 if (cfs != nullptr) {
4237 if (cfs->source() != nullptr) {
4238 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4239 if (module_name != nullptr) {
4240 // When the boot loader created the stream, it didn't know the module name
4241 // yet. Let's format it now.
4242 if (cfs->from_boot_loader_modules_image()) {
4243 info_stream.print(" source: jrt:/%s", module_name);
4244 } else {
4245 info_stream.print(" source: %s", cfs->source());
4246 }
4247 } else {
4248 info_stream.print(" source: %s", cfs->source());
4249 }
4250 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4251 Thread* current = Thread::current();
4252 Klass* caller = current->is_Java_thread() ?
4253 JavaThread::cast(current)->security_get_caller_class(1):
4254 nullptr;
4255 // caller can be null, for example, during a JVMTI VM_Init hook
4256 if (caller != nullptr) {
4257 info_stream.print(" source: instance of %s", caller->external_name());
4258 } else {
4259 // source is unknown
4260 }
4261 } else {
4262 oop class_loader = loader_data->class_loader();
4263 info_stream.print(" source: %s", class_loader->klass()->external_name());
4264 }
4265 } else {
4266 assert(this->in_aot_cache(), "must be");
4267 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
4268 info_stream.print(" source: shared objects file (top)");
4269 } else {
4270 info_stream.print(" source: shared objects file");
4271 }
4272 }
4273
4274 msg.info("%s", info_stream.as_string());
4275
4276 if (log_is_enabled(Debug, class, load)) {
4277 stringStream debug_stream;
4278
4279 // Class hierarchy info
4280 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4281 p2i(this), p2i(super()));
4282
4283 // Interfaces
4284 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4285 debug_stream.print(" interfaces:");
4286 int length = local_interfaces()->length();
4287 for (int i = 0; i < length; i++) {
4288 debug_stream.print(" " PTR_FORMAT,
4289 p2i(local_interfaces()->at(i)));
4290 }
4291 }
4292
4293 // Class loader
4294 debug_stream.print(" loader: [");
4295 loader_data->print_value_on(&debug_stream);
4296 debug_stream.print("]");
4297
4298 // Classfile checksum
4299 if (cfs) {
4300 debug_stream.print(" bytes: %d checksum: %08x",
4301 cfs->length(),
4302 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4303 cfs->length()));
4304 }
4305
4306 msg.debug("%s", debug_stream.as_string());
4307 }
4308 }
4309
4310 void InstanceKlass::print_class_load_cause_logging() const {
4311 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4312 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4313 JavaThread* current = JavaThread::current();
4314 ResourceMark rm(current);
4315 const char* name = external_name();
4316
4317 if (LogClassLoadingCauseFor == nullptr ||
4318 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4319 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4320 return;
4321 }
4322
4323 // Log Java stack first
4324 {
4325 LogMessage(class, load, cause) msg;
4326 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4327
4328 info_stream.print_cr("Java stack when loading %s:", name);
4329 current->print_stack_on(&info_stream);
4330 }
4331
4332 // Log native stack second
4333 if (log_cause_native) {
4334 // Log to string first so that lines can be indented
4335 stringStream stack_stream;
4336 char buf[O_BUFLEN];
4337 address lastpc = nullptr;
4338 NativeStackPrinter nsp(current);
4339 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4340 true /* print_source_info */, -1 /* max stack */);
4341
4342 LogMessage(class, load, cause, native) msg;
4343 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4344 info_stream.print_cr("Native stack when loading %s:", name);
4345
4346 // Print each native stack line to the log
4347 int size = (int) stack_stream.size();
4348 char* stack = stack_stream.as_string();
4349 char* stack_end = stack + size;
4350 char* line_start = stack;
4351 for (char* p = stack; p < stack_end; p++) {
4352 if (*p == '\n') {
4353 *p = '\0';
4354 info_stream.print_cr("\t%s", line_start);
4355 line_start = p + 1;
4356 }
4357 }
4358 if (line_start < stack_end) {
4359 info_stream.print_cr("\t%s", line_start);
4360 }
4361 }
4362 }
4363 }
4364
4365 // Verification
4366
4367 class VerifyFieldClosure: public BasicOopIterateClosure {
4368 protected:
4369 template <class T> void do_oop_work(T* p) {
4370 oop obj = RawAccess<>::oop_load(p);
4371 if (!oopDesc::is_oop_or_null(obj)) {
4372 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4373 Universe::print_on(tty);
4374 guarantee(false, "boom");
4375 }
4376 }
4377 public:
4378 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4379 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4380 };
4381
4382 void InstanceKlass::verify_on(outputStream* st) {
4383 #ifndef PRODUCT
4384 // Avoid redundant verifies, this really should be in product.
4385 if (_verify_count == Universe::verify_count()) return;
4386 _verify_count = Universe::verify_count();
4387 #endif
4388
4389 // Verify Klass
4390 Klass::verify_on(st);
4391
4392 // Verify that klass is present in ClassLoaderData
4393 guarantee(class_loader_data()->contains_klass(this),
4394 "this class isn't found in class loader data");
4395
4396 // Verify vtables
4397 if (is_linked()) {
4398 // $$$ This used to be done only for m/s collections. Doing it
4399 // always seemed a valid generalization. (DLD -- 6/00)
4400 vtable().verify(st);
4401 }
4402
4403 // Verify first subklass
4404 if (subklass() != nullptr) {
4405 guarantee(subklass()->is_klass(), "should be klass");
4406 }
4407
4408 // Verify siblings
4409 Klass* super = this->super();
4410 Klass* sib = next_sibling();
4411 if (sib != nullptr) {
4412 if (sib == this) {
4413 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4414 }
4415
4416 guarantee(sib->is_klass(), "should be klass");
4417 guarantee(sib->super() == super, "siblings should have same superklass");
4418 }
4419
4420 // Verify local interfaces
4421 if (local_interfaces()) {
4422 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4423 for (int j = 0; j < local_interfaces->length(); j++) {
4424 InstanceKlass* e = local_interfaces->at(j);
4425 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4426 }
4427 }
4428
4429 // Verify transitive interfaces
4430 if (transitive_interfaces() != nullptr) {
4431 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4432 for (int j = 0; j < transitive_interfaces->length(); j++) {
4433 InstanceKlass* e = transitive_interfaces->at(j);
4434 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4435 }
4436 }
4437
4438 // Verify methods
4439 if (methods() != nullptr) {
4440 Array<Method*>* methods = this->methods();
4441 for (int j = 0; j < methods->length(); j++) {
4442 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4443 }
4444 for (int j = 0; j < methods->length() - 1; j++) {
4445 Method* m1 = methods->at(j);
4446 Method* m2 = methods->at(j + 1);
4447 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4448 }
4449 }
4450
4451 // Verify method ordering
4452 if (method_ordering() != nullptr) {
4453 Array<int>* method_ordering = this->method_ordering();
4454 int length = method_ordering->length();
4455 if (JvmtiExport::can_maintain_original_method_order() ||
4456 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4457 guarantee(length == methods()->length(), "invalid method ordering length");
4458 jlong sum = 0;
4459 for (int j = 0; j < length; j++) {
4460 int original_index = method_ordering->at(j);
4461 guarantee(original_index >= 0, "invalid method ordering index");
4462 guarantee(original_index < length, "invalid method ordering index");
4463 sum += original_index;
4464 }
4465 // Verify sum of indices 0,1,...,length-1
4466 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4467 } else {
4468 guarantee(length == 0, "invalid method ordering length");
4469 }
4470 }
4471
4472 // Verify default methods
4473 if (default_methods() != nullptr) {
4474 Array<Method*>* methods = this->default_methods();
4475 for (int j = 0; j < methods->length(); j++) {
4476 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4477 }
4478 for (int j = 0; j < methods->length() - 1; j++) {
4479 Method* m1 = methods->at(j);
4480 Method* m2 = methods->at(j + 1);
4481 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4482 }
4483 }
4484
4485 // Verify JNI static field identifiers
4486 if (jni_ids() != nullptr) {
4487 jni_ids()->verify(this);
4488 }
4489
4490 // Verify other fields
4491 if (constants() != nullptr) {
4492 guarantee(constants()->is_constantPool(), "should be constant pool");
4493 }
4494 }
4495
4496 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4497 Klass::oop_verify_on(obj, st);
4498 VerifyFieldClosure blk;
4499 obj->oop_iterate(&blk);
4500 }
4501
4502 // JNIid class for jfieldIDs only
4503 // Note to reviewers:
4504 // These JNI functions are just moved over to column 1 and not changed
4505 // in the compressed oops workspace.
4506 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4507 _holder = holder;
4508 _offset = offset;
4509 _next = next;
4510 DEBUG_ONLY(_is_static_field_id = false;)
4511 }
4512
4513 JNIid* JNIid::find(int offset) {
4514 JNIid* current = this;
4515 while (current != nullptr) {
4516 if (current->offset() == offset) return current;
4517 current = current->next();
4518 }
4519 return nullptr;
4520 }
4521
4522 void JNIid::deallocate(JNIid* current) {
4523 while (current != nullptr) {
4524 JNIid* next = current->next();
4525 delete current;
4526 current = next;
4527 }
4528 }
4529
4530 void JNIid::verify(InstanceKlass* holder) {
4531 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4532 int end_field_offset;
4533 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4534
4535 JNIid* current = this;
4536 while (current != nullptr) {
4537 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4538 #ifdef ASSERT
4539 int o = current->offset();
4540 if (current->is_static_field_id()) {
4541 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4542 }
4543 #endif
4544 current = current->next();
4545 }
4546 }
4547
4548 void InstanceKlass::set_init_state(ClassState state) {
4549 #ifdef ASSERT
4550 bool good_state = in_aot_cache() ? (_init_state <= state)
4551 : (_init_state < state);
4552 assert(good_state || state == allocated, "illegal state transition");
4553 #endif
4554 assert(_init_thread == nullptr, "should be cleared before state change");
4555 AtomicAccess::release_store(&_init_state, state);
4556 }
4557
4558 #if INCLUDE_JVMTI
4559
4560 // RedefineClasses() support for previous versions
4561
4562 // Globally, there is at least one previous version of a class to walk
4563 // during class unloading, which is saved because old methods in the class
4564 // are still running. Otherwise the previous version list is cleaned up.
4565 bool InstanceKlass::_should_clean_previous_versions = false;
4566
4567 // Returns true if there are previous versions of a class for class
4568 // unloading only. Also resets the flag to false. purge_previous_version
4569 // will set the flag to true if there are any left, i.e., if there's any
4570 // work to do for next time. This is to avoid the expensive code cache
4571 // walk in CLDG::clean_deallocate_lists().
4572 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4573 bool ret = _should_clean_previous_versions;
4574 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4575 ret ? "true" : "false");
4576 _should_clean_previous_versions = false;
4577 return ret;
4578 }
4579
4580 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4581 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4582 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4583 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4584 Array<Method*>* method_refs = klass->methods();
4585 for (int k = 0; k < method_refs->length(); k++) {
4586 Method* method = method_refs->at(k);
4587 // Only need to clear obsolete methods.
4588 if (method != nullptr && method->is_obsolete()) {
4589 method->clear_jmethod_id();
4590 }
4591 }
4592 }
4593
4594 // Purge previous versions before adding new previous versions of the class and
4595 // during class unloading.
4596 void InstanceKlass::purge_previous_version_list() {
4597 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4598 assert(has_been_redefined(), "Should only be called for main class");
4599
4600 // Quick exit.
4601 if (previous_versions() == nullptr) {
4602 return;
4603 }
4604
4605 // This klass has previous versions so see what we can cleanup
4606 // while it is safe to do so.
4607
4608 int deleted_count = 0; // leave debugging breadcrumbs
4609 int live_count = 0;
4610 ClassLoaderData* loader_data = class_loader_data();
4611 assert(loader_data != nullptr, "should never be null");
4612
4613 ResourceMark rm;
4614 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4615
4616 // previous versions are linked together through the InstanceKlass
4617 InstanceKlass* pv_node = previous_versions();
4618 InstanceKlass* last = this;
4619 int version = 0;
4620
4621 // check the previous versions list
4622 for (; pv_node != nullptr; ) {
4623
4624 ConstantPool* pvcp = pv_node->constants();
4625 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4626
4627 if (!pvcp->on_stack()) {
4628 // If the constant pool isn't on stack, none of the methods
4629 // are executing. Unlink this previous_version.
4630 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4631 // so will be deallocated during the next phase of class unloading.
4632 log_trace(redefine, class, iklass, purge)
4633 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4634 // Unlink from previous version list.
4635 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4636 InstanceKlass* next = pv_node->previous_versions();
4637 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4638 pv_node->link_previous_versions(nullptr); // point next to null
4639 last->link_previous_versions(next);
4640 // Delete this node directly. Nothing is referring to it and we don't
4641 // want it to increase the counter for metadata to delete in CLDG.
4642 MetadataFactory::free_metadata(loader_data, pv_node);
4643 pv_node = next;
4644 deleted_count++;
4645 version++;
4646 continue;
4647 } else {
4648 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4649 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4650 live_count++;
4651 if (pvcp->in_aot_cache()) {
4652 // Shared previous versions can never be removed so no cleaning is needed.
4653 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4654 } else {
4655 // Previous version alive, set that clean is needed for next time.
4656 _should_clean_previous_versions = true;
4657 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4658 }
4659 }
4660
4661 // next previous version
4662 last = pv_node;
4663 pv_node = pv_node->previous_versions();
4664 version++;
4665 }
4666 log_trace(redefine, class, iklass, purge)
4667 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4668 }
4669
4670 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4671 int emcp_method_count) {
4672 int obsolete_method_count = old_methods->length() - emcp_method_count;
4673
4674 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4675 _previous_versions != nullptr) {
4676 // We have a mix of obsolete and EMCP methods so we have to
4677 // clear out any matching EMCP method entries the hard way.
4678 int local_count = 0;
4679 for (int i = 0; i < old_methods->length(); i++) {
4680 Method* old_method = old_methods->at(i);
4681 if (old_method->is_obsolete()) {
4682 // only obsolete methods are interesting
4683 Symbol* m_name = old_method->name();
4684 Symbol* m_signature = old_method->signature();
4685
4686 // previous versions are linked together through the InstanceKlass
4687 int j = 0;
4688 for (InstanceKlass* prev_version = _previous_versions;
4689 prev_version != nullptr;
4690 prev_version = prev_version->previous_versions(), j++) {
4691
4692 Array<Method*>* method_refs = prev_version->methods();
4693 for (int k = 0; k < method_refs->length(); k++) {
4694 Method* method = method_refs->at(k);
4695
4696 if (!method->is_obsolete() &&
4697 method->name() == m_name &&
4698 method->signature() == m_signature) {
4699 // The current RedefineClasses() call has made all EMCP
4700 // versions of this method obsolete so mark it as obsolete
4701 log_trace(redefine, class, iklass, add)
4702 ("%s(%s): flush obsolete method @%d in version @%d",
4703 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4704
4705 method->set_is_obsolete();
4706 break;
4707 }
4708 }
4709
4710 // The previous loop may not find a matching EMCP method, but
4711 // that doesn't mean that we can optimize and not go any
4712 // further back in the PreviousVersion generations. The EMCP
4713 // method for this generation could have already been made obsolete,
4714 // but there still may be an older EMCP method that has not
4715 // been made obsolete.
4716 }
4717
4718 if (++local_count >= obsolete_method_count) {
4719 // no more obsolete methods so bail out now
4720 break;
4721 }
4722 }
4723 }
4724 }
4725 }
4726
4727 // Save the scratch_class as the previous version if any of the methods are running.
4728 // The previous_versions are used to set breakpoints in EMCP methods and they are
4729 // also used to clean MethodData links to redefined methods that are no longer running.
4730 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4731 int emcp_method_count) {
4732 assert(Thread::current()->is_VM_thread(),
4733 "only VMThread can add previous versions");
4734
4735 ResourceMark rm;
4736 log_trace(redefine, class, iklass, add)
4737 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4738
4739 // Clean out old previous versions for this class
4740 purge_previous_version_list();
4741
4742 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4743 // a previous redefinition may be made obsolete by this redefinition.
4744 Array<Method*>* old_methods = scratch_class->methods();
4745 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4746
4747 // If the constant pool for this previous version of the class
4748 // is not marked as being on the stack, then none of the methods
4749 // in this previous version of the class are on the stack so
4750 // we don't need to add this as a previous version.
4751 ConstantPool* cp_ref = scratch_class->constants();
4752 if (!cp_ref->on_stack()) {
4753 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4754 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4755 return;
4756 }
4757
4758 // Add previous version if any methods are still running or if this is
4759 // a shared class which should never be removed.
4760 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4761 scratch_class->link_previous_versions(previous_versions());
4762 link_previous_versions(scratch_class);
4763 if (cp_ref->in_aot_cache()) {
4764 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4765 } else {
4766 // We only set clean_previous_versions flag for processing during class
4767 // unloading for non-shared classes.
4768 _should_clean_previous_versions = true;
4769 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4770 }
4771 } // end add_previous_version()
4772
4773 #endif // INCLUDE_JVMTI
4774
4775 Method* InstanceKlass::method_with_idnum(int idnum) const {
4776 Method* m = nullptr;
4777 if (idnum < methods()->length()) {
4778 m = methods()->at(idnum);
4779 }
4780 if (m == nullptr || m->method_idnum() != idnum) {
4781 for (int index = 0; index < methods()->length(); ++index) {
4782 m = methods()->at(index);
4783 if (m->method_idnum() == idnum) {
4784 return m;
4785 }
4786 }
4787 // None found, return null for the caller to handle.
4788 return nullptr;
4789 }
4790 return m;
4791 }
4792
4793
4794 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4795 if (idnum >= methods()->length()) {
4796 return nullptr;
4797 }
4798 Method* m = methods()->at(idnum);
4799 if (m != nullptr && m->orig_method_idnum() == idnum) {
4800 return m;
4801 }
4802 // Obsolete method idnum does not match the original idnum
4803 for (int index = 0; index < methods()->length(); ++index) {
4804 m = methods()->at(index);
4805 if (m->orig_method_idnum() == idnum) {
4806 return m;
4807 }
4808 }
4809 // None found, return null for the caller to handle.
4810 return nullptr;
4811 }
4812
4813
4814 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4815 const InstanceKlass* holder = get_klass_version(version);
4816 if (holder == nullptr) {
4817 return nullptr; // The version of klass is gone, no method is found
4818 }
4819 return holder->method_with_orig_idnum(idnum);
4820 }
4821
4822 #if INCLUDE_JVMTI
4823 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4824 return _cached_class_file;
4825 }
4826
4827 jint InstanceKlass::get_cached_class_file_len() {
4828 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4829 }
4830
4831 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4832 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4833 }
4834 #endif
4835
4836 // Make a step iterating over the class hierarchy under the root class.
4837 // Skips subclasses if requested.
4838 void ClassHierarchyIterator::next() {
4839 assert(_current != nullptr, "required");
4840 if (_visit_subclasses && _current->subklass() != nullptr) {
4841 _current = _current->subklass();
4842 return; // visit next subclass
4843 }
4844 _visit_subclasses = true; // reset
4845 while (_current->next_sibling() == nullptr && _current != _root) {
4846 _current = _current->java_super(); // backtrack; no more sibling subclasses left
4847 }
4848 if (_current == _root) {
4849 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4850 _current = nullptr;
4851 return;
4852 }
4853 _current = _current->next_sibling();
4854 return; // visit next sibling subclass
4855 }