1 /*
2 * Copyright (c) 1997, 2026, 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/layoutKind.hpp"
74 #include "oops/markWord.hpp"
75 #include "oops/method.hpp"
76 #include "oops/oop.inline.hpp"
77 #include "oops/recordComponent.hpp"
78 #include "oops/refArrayKlass.hpp"
79 #include "oops/symbol.hpp"
80 #include "prims/jvmtiExport.hpp"
81 #include "prims/jvmtiRedefineClasses.hpp"
82 #include "prims/jvmtiThreadState.hpp"
83 #include "prims/methodComparator.hpp"
84 #include "runtime/arguments.hpp"
85 #include "runtime/atomicAccess.hpp"
86 #include "runtime/deoptimization.hpp"
87 #include "runtime/fieldDescriptor.inline.hpp"
88 #include "runtime/handles.inline.hpp"
89 #include "runtime/javaCalls.hpp"
90 #include "runtime/javaThread.inline.hpp"
91 #include "runtime/mutexLocker.hpp"
92 #include "runtime/orderAccess.hpp"
93 #include "runtime/os.inline.hpp"
94 #include "runtime/reflection.hpp"
95 #include "runtime/synchronizer.hpp"
96 #include "runtime/threads.hpp"
97 #include "services/classLoadingService.hpp"
98 #include "services/finalizerService.hpp"
99 #include "services/threadService.hpp"
100 #include "utilities/dtrace.hpp"
101 #include "utilities/events.hpp"
102 #include "utilities/macros.hpp"
103 #include "utilities/nativeStackPrinter.hpp"
104 #include "utilities/ostream.hpp"
105 #include "utilities/stringUtils.hpp"
106 #ifdef COMPILER1
107 #include "c1/c1_Compiler.hpp"
108 #endif
109 #if INCLUDE_JFR
110 #include "jfr/jfrEvents.hpp"
111 #endif
112
113 #ifdef DTRACE_ENABLED
114
115
116 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
117 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
118 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
119 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
120 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
121 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
122 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
123 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
124 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
125 { \
126 char* data = nullptr; \
127 int len = 0; \
128 Symbol* clss_name = name(); \
129 if (clss_name != nullptr) { \
130 data = (char*)clss_name->bytes(); \
131 len = clss_name->utf8_length(); \
132 } \
133 HOTSPOT_CLASS_INITIALIZATION_##type( \
134 data, len, (void*)class_loader(), thread_type); \
135 }
136
137 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
138 { \
139 char* data = nullptr; \
140 int len = 0; \
141 Symbol* clss_name = name(); \
142 if (clss_name != nullptr) { \
143 data = (char*)clss_name->bytes(); \
144 len = clss_name->utf8_length(); \
145 } \
146 HOTSPOT_CLASS_INITIALIZATION_##type( \
147 data, len, (void*)class_loader(), thread_type, wait); \
148 }
149
150 #else // ndef DTRACE_ENABLED
151
152 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
153 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
154
155 #endif // ndef DTRACE_ENABLED
156
157 void InlineLayoutInfo::metaspace_pointers_do(MetaspaceClosure* it) {
158 log_trace(cds)("Iter(InlineFieldInfo): %p", this);
159 it->push(&_klass);
160 }
161
162 void InlineLayoutInfo::print() const {
163 print_on(tty);
164 }
165
166 void InlineLayoutInfo::print_on(outputStream* st) const {
167 st->print_cr("_klass: " PTR_FORMAT, p2i(_klass));
168 if (_klass != nullptr) {
169 StreamIndentor si(st);
170 _klass->print_on(st);
171 st->cr();
172 }
173
174 st->print("_layout: ");
175 LayoutKindHelper::print_on(_kind, st);
176 st->cr();
177
178 st->print("_null_marker_offset: %d", _null_marker_offset);
179 }
180
181 bool InstanceKlass::_finalization_enabled = true;
182
183 static inline bool is_class_loader(const Symbol* class_name,
184 const ClassFileParser& parser) {
185 assert(class_name != nullptr, "invariant");
186
187 if (class_name == vmSymbols::java_lang_ClassLoader()) {
188 return true;
189 }
190
191 if (vmClasses::ClassLoader_klass_is_loaded()) {
192 const Klass* const super_klass = parser.super_klass();
193 if (super_klass != nullptr) {
194 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
195 return true;
196 }
197 }
198 }
199 return false;
200 }
201
202 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
203 return field(index).field_flags().is_null_free_inline_type();
204 }
205
206 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
207 if (_loadable_descriptors == nullptr) return false;
208 for (int i = 0; i < _loadable_descriptors->length(); i++) {
209 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
210 if (class_name == name) return true;
211 }
212 return false;
213 }
214
215 static inline bool is_stack_chunk_class(const Symbol* class_name,
216 const ClassLoaderData* loader_data) {
217 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
218 loader_data->is_the_null_class_loader_data());
219 }
220
221 // private: called to verify that k is a static member of this nest.
222 // We know that k is an instance class in the same package and hence the
223 // same classloader.
224 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
225 assert(!is_hidden(), "unexpected hidden class");
226 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
227 if (log_is_enabled(Trace, class, nestmates)) {
228 ResourceMark rm(current);
229 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
230 k->external_name(), this->external_name());
231 }
232 return false;
233 }
234
235 if (log_is_enabled(Trace, class, nestmates)) {
236 ResourceMark rm(current);
237 log_trace(class, nestmates)("Checking nest membership of %s in %s",
238 k->external_name(), this->external_name());
239 }
240
241 // Check for the named class in _nest_members.
242 // We don't resolve, or load, any classes.
243 for (int i = 0; i < _nest_members->length(); i++) {
244 int cp_index = _nest_members->at(i);
245 Symbol* name = _constants->klass_name_at(cp_index);
246 if (name == k->name()) {
247 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
248 return true;
249 }
250 }
251 log_trace(class, nestmates)("- class is NOT a nest member!");
252 return false;
253 }
254
255 // Called to verify that k is a permitted subclass of this class.
256 // The incoming stringStream is used to format the messages for error logging and for the caller
257 // to use for exception throwing.
258 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
259 Thread* current = Thread::current();
260 assert(k != nullptr, "sanity check");
261 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
262 "unexpected empty _permitted_subclasses array");
263
264 if (log_is_enabled(Trace, class, sealed)) {
265 ResourceMark rm(current);
266 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
267 k->external_name(), this->external_name());
268 }
269
270 // Check that the class and its super are in the same module.
271 if (k->module() != this->module()) {
272 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
273 "and sealed class %s is in module '%s' with loader %s",
274 k->external_name(),
275 k->module()->name_as_C_string(),
276 k->module()->loader_data()->loader_name_and_id(),
277 this->external_name(),
278 this->module()->name_as_C_string(),
279 this->module()->loader_data()->loader_name_and_id());
280 log_trace(class, sealed)(" - %s", ss.as_string());
281 return false;
282 }
283
284 if (!k->is_public() && !is_same_class_package(k)) {
285 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
286 "and sealed class %s is in package '%s' with classloader %s",
287 k->external_name(),
288 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
289 k->module()->loader_data()->loader_name_and_id(),
290 this->external_name(),
291 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
292 this->module()->loader_data()->loader_name_and_id());
293 log_trace(class, sealed)(" - %s", ss.as_string());
294 return false;
295 }
296
297 for (int i = 0; i < _permitted_subclasses->length(); i++) {
298 int cp_index = _permitted_subclasses->at(i);
299 Symbol* name = _constants->klass_name_at(cp_index);
300 if (name == k->name()) {
301 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
302 return true;
303 }
304 }
305
306 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
307 k->external_name(), this->external_name());
308 log_trace(class, sealed)(" - %s", ss.as_string());
309 return false;
310 }
311
312 // Return nest-host class, resolving, validating and saving it if needed.
313 // In cases where this is called from a thread that cannot do classloading
314 // (such as a native JIT thread) then we simply return null, which in turn
315 // causes the access check to return false. Such code will retry the access
316 // from a more suitable environment later. Otherwise the _nest_host is always
317 // set once this method returns.
318 // Any errors from nest-host resolution must be preserved so they can be queried
319 // from higher-level access checking code, and reported as part of access checking
320 // exceptions.
321 // VirtualMachineErrors are propagated with a null return.
322 // Under any conditions where the _nest_host can be set to non-null the resulting
323 // value of it and, if applicable, the nest host resolution/validation error,
324 // are idempotent.
325 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
326 InstanceKlass* nest_host_k = _nest_host;
327 if (nest_host_k != nullptr) {
328 return nest_host_k;
329 }
330
331 ResourceMark rm(THREAD);
332
333 // need to resolve and save our nest-host class.
334 if (_nest_host_index != 0) { // we have a real nest_host
335 // Before trying to resolve check if we're in a suitable context
336 bool can_resolve = THREAD->can_call_java();
337 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
338 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
339 this->external_name());
340 return nullptr; // sentinel to say "try again from a different context"
341 }
342
343 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
344 this->external_name(),
345 _constants->klass_name_at(_nest_host_index)->as_C_string());
346
347 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
348 if (HAS_PENDING_EXCEPTION) {
349 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
350 return nullptr; // propagate VMEs
351 }
352 stringStream ss;
353 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
354 ss.print("Nest host resolution of %s with host %s failed: ",
355 this->external_name(), target_host_class);
356 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
357 constantPoolHandle cph(THREAD, constants());
358 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
359 CLEAR_PENDING_EXCEPTION;
360
361 log_trace(class, nestmates)("%s", ss.base());
362 } else {
363 // A valid nest-host is an instance class in the current package that lists this
364 // class as a nest member. If any of these conditions are not met the class is
365 // its own nest-host.
366 const char* error = nullptr;
367
368 // JVMS 5.4.4 indicates package check comes first
369 if (is_same_class_package(k)) {
370 // Now check actual membership. We can't be a member if our "host" is
371 // not an instance class.
372 if (k->is_instance_klass()) {
373 nest_host_k = InstanceKlass::cast(k);
374 bool is_member = nest_host_k->has_nest_member(THREAD, this);
375 if (is_member) {
376 _nest_host = nest_host_k; // save resolved nest-host value
377
378 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
379 this->external_name(), k->external_name());
380 return nest_host_k;
381 } else {
382 error = "current type is not listed as a nest member";
383 }
384 } else {
385 error = "host is not an instance class";
386 }
387 } else {
388 error = "types are in different packages";
389 }
390
391 // something went wrong, so record what and log it
392 {
393 stringStream ss;
394 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
395 this->external_name(),
396 this->class_loader_data()->loader_name_and_id(),
397 k->external_name(),
398 k->class_loader_data()->loader_name_and_id(),
399 error);
400 constantPoolHandle cph(THREAD, constants());
401 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss);
402 log_trace(class, nestmates)("%s", ss.base());
403 }
404 }
405 } else {
406 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
407 this->external_name());
408 }
409
410 // Either not in an explicit nest, or else an error occurred, so
411 // the nest-host is set to `this`. Any thread that sees this assignment
412 // will also see any setting of nest_host_error(), if applicable.
413 return (_nest_host = this);
414 }
415
416 // Dynamic nest member support: set this class's nest host to the given class.
417 // This occurs as part of the class definition, as soon as the instanceKlass
418 // has been created and doesn't require further resolution. The code:
419 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
420 // results in:
421 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
422 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
423 // We also know the "host" is a valid nest-host in the same package so we can
424 // assert some of those facts.
425 void InstanceKlass::set_nest_host(InstanceKlass* host) {
426 assert(is_hidden(), "must be a hidden class");
427 assert(host != nullptr, "null nest host specified");
428 assert(_nest_host == nullptr, "current class has resolved nest-host");
429 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
430 nest_host_error());
431 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
432 (host->_nest_host == host), "proposed host is not a valid nest-host");
433 // Can't assert this as package is not set yet:
434 // assert(is_same_class_package(host), "proposed host is in wrong package");
435
436 if (log_is_enabled(Trace, class, nestmates)) {
437 ResourceMark rm;
438 const char* msg = "";
439 // a hidden class does not expect a statically defined nest-host
440 if (_nest_host_index > 0) {
441 msg = "(the NestHost attribute in the current class is ignored)";
442 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
443 msg = "(the NestMembers attribute in the current class is ignored)";
444 }
445 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
446 this->external_name(),
447 host->external_name(),
448 msg);
449 }
450 // set dynamic nest host
451 _nest_host = host;
452 // Record dependency to keep nest host from being unloaded before this class.
453 ClassLoaderData* this_key = class_loader_data();
454 assert(this_key != nullptr, "sanity");
455 this_key->record_dependency(host);
456 }
457
458 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
459 // or we are k's nest_host - all of which is covered by comparing the two
460 // resolved_nest_hosts.
461 // Any exceptions (i.e. VMEs) are propagated.
462 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
463
464 assert(this != k, "this should be handled by higher-level code");
465
466 // Per JVMS 5.4.4 we first resolve and validate the current class, then
467 // the target class k.
468
469 InstanceKlass* cur_host = nest_host(CHECK_false);
470 if (cur_host == nullptr) {
471 return false;
472 }
473
474 Klass* k_nest_host = k->nest_host(CHECK_false);
475 if (k_nest_host == nullptr) {
476 return false;
477 }
478
479 bool access = (cur_host == k_nest_host);
480
481 ResourceMark rm(THREAD);
482 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
483 this->external_name(),
484 access ? "" : "NOT ",
485 k->external_name());
486 return access;
487 }
488
489 const char* InstanceKlass::nest_host_error() {
490 if (_nest_host_index == 0) {
491 return nullptr;
492 } else {
493 constantPoolHandle cph(Thread::current(), constants());
494 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
495 }
496 }
497
498 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
499 const int size = InstanceKlass::size(parser.vtable_size(),
500 parser.itable_size(),
501 nonstatic_oop_map_size(parser.total_oop_map_count()),
502 parser.is_interface(),
503 parser.is_inline_type());
504
505 const Symbol* const class_name = parser.class_name();
506 assert(class_name != nullptr, "invariant");
507 ClassLoaderData* loader_data = parser.loader_data();
508 assert(loader_data != nullptr, "invariant");
509
510 InstanceKlass* ik;
511
512 // Allocation
513 if (parser.is_instance_ref_klass()) {
514 // java.lang.ref.Reference
515 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
516 } else if (class_name == vmSymbols::java_lang_Class()) {
517 // mirror - java.lang.Class
518 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
519 } else if (is_stack_chunk_class(class_name, loader_data)) {
520 // stack chunk
521 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
522 } else if (is_class_loader(class_name, parser)) {
523 // class loader - java.lang.ClassLoader
524 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
525 } else if (parser.is_inline_type()) {
526 // inline type
527 ik = new (loader_data, size, THREAD) InlineKlass(parser);
528 } else {
529 // normal
530 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
531 }
532
533 if (ik != nullptr && UseCompressedClassPointers) {
534 assert(CompressedKlassPointers::is_encodable(ik),
535 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
536 }
537
538 // Check for pending exception before adding to the loader data and incrementing
539 // class count. Can get OOM here.
540 if (HAS_PENDING_EXCEPTION) {
541 return nullptr;
542 }
543
544 #ifdef ASSERT
545 ik->bounds_check((address) ik->start_of_vtable(), false, size);
546 ik->bounds_check((address) ik->start_of_itable(), false, size);
547 ik->bounds_check((address) ik->end_of_itable(), true, size);
548 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
549 #endif //ASSERT
550 return ik;
551 }
552
553 #ifndef PRODUCT
554 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
555 const char* bad = nullptr;
556 address end = nullptr;
557 if (addr < (address)this) {
558 bad = "before";
559 } else if (addr == (address)this) {
560 if (edge_ok) return true;
561 bad = "just before";
562 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
563 if (edge_ok) return true;
564 bad = "just after";
565 } else if (addr > end) {
566 bad = "after";
567 } else {
568 return true;
569 }
570 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
571 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
572 Verbose = WizardMode = true; this->print(); //@@
573 return false;
574 }
575 #endif //PRODUCT
576
577 // copy method ordering from resource area to Metaspace
578 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
579 if (m != nullptr) {
580 // allocate a new array and copy contents (memcpy?)
581 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
582 for (int i = 0; i < m->length(); i++) {
583 _method_ordering->at_put(i, m->at(i));
584 }
585 } else {
586 _method_ordering = Universe::the_empty_int_array();
587 }
588 }
589
590 // create a new array of vtable_indices for default methods
591 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
592 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
593 assert(default_vtable_indices() == nullptr, "only create once");
594 set_default_vtable_indices(vtable_indices);
595 return vtable_indices;
596 }
597
598
599 InstanceKlass::InstanceKlass() {
600 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
601 }
602
603 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, markWord prototype_header, ReferenceType reference_type) :
604 Klass(kind, prototype_header),
605 _nest_members(nullptr),
606 _nest_host(nullptr),
607 _permitted_subclasses(nullptr),
608 _record_components(nullptr),
609 _static_field_size(parser.static_field_size()),
610 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
611 _itable_len(parser.itable_size()),
612 _nest_host_index(0),
613 _init_state(allocated),
614 _reference_type(reference_type),
615 _acmp_maps_offset(0),
616 _init_thread(nullptr),
617 _inline_layout_info_array(nullptr),
618 _loadable_descriptors(nullptr),
619 _acmp_maps_array(nullptr),
620 _adr_inline_klass_members(nullptr)
621 {
622 set_vtable_length(parser.vtable_size());
623 set_access_flags(parser.access_flags());
624 if (parser.is_hidden()) set_is_hidden();
625 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
626 false));
627 if (parser.has_inlined_fields()) {
628 set_has_inlined_fields();
629 }
630
631 assert(nullptr == _methods, "underlying memory not zeroed?");
632 assert(is_instance_klass(), "is layout incorrect?");
633 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
634 }
635
636 void InstanceKlass::set_is_cloneable() {
637 if (name() == vmSymbols::java_lang_invoke_MemberName()) {
638 assert(is_final(), "no subclasses allowed");
639 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
640 } else if (reference_type() != REF_NONE) {
641 // Reference cloning should not be intrinsified and always happen in JVM_Clone.
642 } else {
643 set_is_cloneable_fast();
644 }
645 }
646
647 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
648 Array<Method*>* methods) {
649 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
650 !methods->in_aot_cache()) {
651 for (int i = 0; i < methods->length(); i++) {
652 Method* method = methods->at(i);
653 if (method == nullptr) continue; // maybe null if error processing
654 // Only want to delete methods that are not executing for RedefineClasses.
655 // The previous version will point to them so they're not totally dangling
656 assert (!method->on_stack(), "shouldn't be called with methods on stack");
657 MetadataFactory::free_metadata(loader_data, method);
658 }
659 MetadataFactory::free_array<Method*>(loader_data, methods);
660 }
661 }
662
663 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
664 const InstanceKlass* super_klass,
665 Array<InstanceKlass*>* local_interfaces,
666 Array<InstanceKlass*>* transitive_interfaces) {
667 // Only deallocate transitive interfaces if not empty, same as super class
668 // or same as local interfaces. See code in parseClassFile.
669 Array<InstanceKlass*>* ti = transitive_interfaces;
670 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
671 // check that the interfaces don't come from super class
672 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
673 super_klass->transitive_interfaces();
674 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) {
675 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
676 }
677 }
678
679 // local interfaces can be empty
680 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
681 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) {
682 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
683 }
684 }
685
686 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
687 Array<RecordComponent*>* record_components) {
688 if (record_components != nullptr && !record_components->in_aot_cache()) {
689 for (int i = 0; i < record_components->length(); i++) {
690 RecordComponent* record_component = record_components->at(i);
691 MetadataFactory::free_metadata(loader_data, record_component);
692 }
693 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
694 }
695 }
696
697 // This function deallocates the metadata and C heap pointers that the
698 // InstanceKlass points to.
699 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
700 // Orphan the mirror first, CMS thinks it's still live.
701 if (java_mirror() != nullptr) {
702 java_lang_Class::set_klass(java_mirror(), nullptr);
703 }
704
705 // Also remove mirror from handles
706 loader_data->remove_handle(_java_mirror);
707
708 // Need to take this class off the class loader data list.
709 loader_data->remove_class(this);
710
711 // The array_klass for this class is created later, after error handling.
712 // For class redefinition, we keep the original class so this scratch class
713 // doesn't have an array class. Either way, assert that there is nothing
714 // to deallocate.
715 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
716
717 // Release C heap allocated data that this points to, which includes
718 // reference counting symbol names.
719 // Can't release the constant pool or MethodData C heap data here because the constant
720 // pool can be deallocated separately from the InstanceKlass for default methods and
721 // redefine classes. MethodData can also be released separately.
722 release_C_heap_structures(/* release_sub_metadata */ false);
723
724 deallocate_methods(loader_data, methods());
725 set_methods(nullptr);
726
727 deallocate_record_components(loader_data, record_components());
728 set_record_components(nullptr);
729
730 if (method_ordering() != nullptr &&
731 method_ordering() != Universe::the_empty_int_array() &&
732 !method_ordering()->in_aot_cache()) {
733 MetadataFactory::free_array<int>(loader_data, method_ordering());
734 }
735 set_method_ordering(nullptr);
736
737 // default methods can be empty
738 if (default_methods() != nullptr &&
739 default_methods() != Universe::the_empty_method_array() &&
740 !default_methods()->in_aot_cache()) {
741 MetadataFactory::free_array<Method*>(loader_data, default_methods());
742 }
743 // Do NOT deallocate the default methods, they are owned by superinterfaces.
744 set_default_methods(nullptr);
745
746 // default methods vtable indices can be empty
747 if (default_vtable_indices() != nullptr &&
748 !default_vtable_indices()->in_aot_cache()) {
749 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
750 }
751 set_default_vtable_indices(nullptr);
752
753
754 // This array is in Klass, but remove it with the InstanceKlass since
755 // this place would be the only caller and it can share memory with transitive
756 // interfaces.
757 if (secondary_supers() != nullptr &&
758 secondary_supers() != Universe::the_empty_klass_array() &&
759 // see comments in compute_secondary_supers about the following cast
760 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
761 !secondary_supers()->in_aot_cache()) {
762 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
763 }
764 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
765
766 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
767 set_transitive_interfaces(nullptr);
768 set_local_interfaces(nullptr);
769
770 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) {
771 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
772 }
773 set_fieldinfo_stream(nullptr);
774
775 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) {
776 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
777 }
778 set_fieldinfo_search_table(nullptr);
779
780 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) {
781 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
782 }
783 set_fields_status(nullptr);
784
785 if (inline_layout_info_array() != nullptr) {
786 MetadataFactory::free_array<InlineLayoutInfo>(loader_data, inline_layout_info_array());
787 }
788 set_inline_layout_info_array(nullptr);
789
790 // If a method from a redefined class is using this constant pool, don't
791 // delete it, yet. The new class's previous version will point to this.
792 if (constants() != nullptr) {
793 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
794 if (!constants()->in_aot_cache()) {
795 MetadataFactory::free_metadata(loader_data, constants());
796 }
797 // Delete any cached resolution errors for the constant pool
798 SystemDictionary::delete_resolution_error(constants());
799
800 set_constants(nullptr);
801 }
802
803 if (inner_classes() != nullptr &&
804 inner_classes() != Universe::the_empty_short_array() &&
805 !inner_classes()->in_aot_cache()) {
806 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
807 }
808 set_inner_classes(nullptr);
809
810 if (nest_members() != nullptr &&
811 nest_members() != Universe::the_empty_short_array() &&
812 !nest_members()->in_aot_cache()) {
813 MetadataFactory::free_array<jushort>(loader_data, nest_members());
814 }
815 set_nest_members(nullptr);
816
817 if (permitted_subclasses() != nullptr &&
818 permitted_subclasses() != Universe::the_empty_short_array() &&
819 !permitted_subclasses()->in_aot_cache()) {
820 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
821 }
822 set_permitted_subclasses(nullptr);
823
824 if (loadable_descriptors() != nullptr &&
825 loadable_descriptors() != Universe::the_empty_short_array() &&
826 !loadable_descriptors()->in_aot_cache()) {
827 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
828 }
829 set_loadable_descriptors(nullptr);
830
831 if (acmp_maps_array() != nullptr) {
832 MetadataFactory::free_array<int>(loader_data, acmp_maps_array());
833 }
834 set_acmp_maps_array(nullptr);
835
836 // We should deallocate the Annotations instance if it's not in shared spaces.
837 if (annotations() != nullptr && !annotations()->in_aot_cache()) {
838 MetadataFactory::free_metadata(loader_data, annotations());
839 }
840 set_annotations(nullptr);
841
842 SystemDictionaryShared::handle_class_unloading(this);
843
844 #if INCLUDE_CDS_JAVA_HEAP
845 if (CDSConfig::is_dumping_heap()) {
846 HeapShared::remove_scratch_objects(this);
847 }
848 #endif
849 }
850
851 bool InstanceKlass::is_record() const {
852 return _record_components != nullptr &&
853 is_final() &&
854 super() == vmClasses::Record_klass();
855 }
856
857 bool InstanceKlass::is_sealed() const {
858 return _permitted_subclasses != nullptr &&
859 _permitted_subclasses != Universe::the_empty_short_array();
860 }
861
862 // JLS 8.9: An enum class is either implicitly final and derives
863 // from java.lang.Enum, or else is implicitly sealed to its
864 // anonymous subclasses. This query detects both kinds.
865 // It does not validate the finality or
866 // sealing conditions: it merely checks for a super of Enum.
867 // This is sufficient for recognizing well-formed enums.
868 bool InstanceKlass::is_enum_subclass() const {
869 InstanceKlass* s = super();
870 return (s == vmClasses::Enum_klass() ||
871 (s != nullptr && s->super() == vmClasses::Enum_klass()));
872 }
873
874 bool InstanceKlass::should_be_initialized() const {
875 return !is_initialized();
876 }
877
878 // Static size helper
879 int InstanceKlass::size(int vtable_length,
880 int itable_length,
881 int nonstatic_oop_map_size,
882 bool is_interface,
883 bool is_inline_type) {
884 return align_metadata_size(header_size() +
885 vtable_length +
886 itable_length +
887 nonstatic_oop_map_size +
888 (is_interface ? (int)sizeof(Klass*) / wordSize : 0) +
889 (is_inline_type ? (int)sizeof(InlineKlass::Members) / wordSize : 0));
890 }
891
892 int InstanceKlass::size() const {
893 return size(vtable_length(),
894 itable_length(),
895 nonstatic_oop_map_size(),
896 is_interface(),
897 is_inline_klass());
898 }
899
900 klassItable InstanceKlass::itable() const {
901 return klassItable(const_cast<InstanceKlass*>(this));
902 }
903
904 // JVMTI spec thinks there are signers and protection domain in the
905 // instanceKlass. These accessors pretend these fields are there.
906 // The hprof specification also thinks these fields are in InstanceKlass.
907 oop InstanceKlass::protection_domain() const {
908 // return the protection_domain from the mirror
909 return java_lang_Class::protection_domain(java_mirror());
910 }
911
912 objArrayOop InstanceKlass::signers() const {
913 // return the signers from the mirror
914 return java_lang_Class::signers(java_mirror());
915 }
916
917 oop InstanceKlass::init_lock() const {
918 // return the init lock from the mirror
919 oop lock = java_lang_Class::init_lock(java_mirror());
920 // Prevent reordering with any access of initialization state
921 OrderAccess::loadload();
922 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
923 "only fully initialized state can have a null lock");
924 return lock;
925 }
926
927 // Set the initialization lock to null so the object can be GC'ed. Any racing
928 // threads to get this lock will see a null lock and will not lock.
929 // That's okay because they all check for initialized state after getting
930 // the lock and return. For preempted vthreads we keep the oop protected
931 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()).
932 void InstanceKlass::fence_and_clear_init_lock() {
933 // make sure previous stores are all done, notably the init_state.
934 OrderAccess::storestore();
935 java_lang_Class::clear_init_lock(java_mirror());
936 assert(!is_not_initialized(), "class must be initialized now");
937 }
938
939 class PreemptableInitCall {
940 JavaThread* _thread;
941 bool _previous;
942 DEBUG_ONLY(InstanceKlass* _previous_klass;)
943 public:
944 PreemptableInitCall(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
945 _previous = thread->at_preemptable_init();
946 _thread->set_at_preemptable_init(true);
947 DEBUG_ONLY(_previous_klass = _thread->preempt_init_klass();)
948 DEBUG_ONLY(_thread->set_preempt_init_klass(ik));
949 }
950 ~PreemptableInitCall() {
951 _thread->set_at_preemptable_init(_previous);
952 DEBUG_ONLY(_thread->set_preempt_init_klass(_previous_klass));
953 }
954 };
955
956 void InstanceKlass::initialize_preemptable(TRAPS) {
957 if (this->should_be_initialized()) {
958 PreemptableInitCall pic(THREAD, this);
959 initialize_impl(THREAD);
960 } else {
961 assert(is_initialized(), "sanity check");
962 }
963 }
964
965 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
966 // process. The step comments refers to the procedure described in that section.
967 // Note: implementation moved to static method to expose the this pointer.
968 void InstanceKlass::initialize(TRAPS) {
969 if (this->should_be_initialized()) {
970 initialize_impl(CHECK);
971 // Note: at this point the class may be initialized
972 // OR it may be in the state of being initialized
973 // in case of recursive initialization!
974 } else {
975 assert(is_initialized(), "sanity check");
976 }
977 }
978
979 #ifdef ASSERT
980 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
981 assert(has_aot_initialized_mirror(), "must be");
982
983 InstanceKlass* s = super();
984 if (s != nullptr) {
985 DEBUG_ONLY(ResourceMark rm);
986 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
987 s->external_name(), external_name());
988 s->assert_no_clinit_will_run_for_aot_initialized_class();
989 }
990
991 Array<InstanceKlass*>* interfaces = local_interfaces();
992 int len = interfaces->length();
993 for (int i = 0; i < len; i++) {
994 InstanceKlass* intf = interfaces->at(i);
995 if (!intf->is_initialized()) {
996 ResourceMark rm;
997 // Note: an interface needs to be marked as is_initialized() only if
998 // - it has a <clinit>
999 // - it has declared a default method.
1000 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
1001 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
1002 intf->external_name(), external_name());
1003 }
1004 }
1005 }
1006 #endif
1007
1008 #if INCLUDE_CDS
1009 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
1010 assert(has_aot_initialized_mirror(), "must be");
1011 assert(CDSConfig::is_loading_heap(), "must be");
1012 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
1013 assert_no_clinit_will_run_for_aot_initialized_class();
1014
1015 if (is_initialized()) {
1016 return;
1017 }
1018
1019 if (is_runtime_setup_required()) {
1020 // Need to take the slow path, which will call the runtimeSetup() function instead
1021 // of <clinit>
1022 initialize(CHECK);
1023 return;
1024 }
1025 if (log_is_enabled(Info, aot, init)) {
1026 ResourceMark rm;
1027 log_info(aot, init)("%s (aot-inited)", external_name());
1028 }
1029
1030 link_class(CHECK);
1031
1032 #ifdef ASSERT
1033 {
1034 Handle h_init_lock(THREAD, init_lock());
1035 ObjectLocker ol(h_init_lock, THREAD);
1036 assert(!is_initialized(), "sanity");
1037 assert(!is_being_initialized(), "sanity");
1038 assert(!is_in_error_state(), "sanity");
1039 }
1040 #endif
1041
1042 set_init_thread(THREAD);
1043 set_initialization_state_and_notify(fully_initialized, CHECK);
1044 }
1045 #endif
1046
1047 bool InstanceKlass::verify_code(TRAPS) {
1048 // 1) Verify the bytecodes
1049 return Verifier::verify(this, should_verify_class(), THREAD);
1050 }
1051
1052 static void load_classes_from_loadable_descriptors_attribute(InstanceKlass *ik, TRAPS) {
1053 if (ik->loadable_descriptors() != Universe::the_empty_short_array() && PreloadClasses) {
1054 ResourceMark rm(THREAD);
1055 HandleMark hm(THREAD);
1056 for (int i = 0; i < ik->loadable_descriptors()->length(); i++) {
1057 Symbol* sig = ik->constants()->symbol_at(ik->loadable_descriptors()->at(i));
1058 if (!Signature::has_envelope(sig)) continue;
1059 TempNewSymbol class_name = Signature::strip_envelope(sig);
1060 if (class_name == ik->name()) continue;
1061 log_info(class, preload)("Preloading of class %s during linking of class %s "
1062 "because of the class is listed in the LoadableDescriptors attribute",
1063 sig->as_C_string(), ik->name()->as_C_string());
1064 oop loader = ik->class_loader();
1065 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1066 Handle(THREAD, loader), THREAD);
1067 if (HAS_PENDING_EXCEPTION) {
1068 CLEAR_PENDING_EXCEPTION;
1069 }
1070 if (klass != nullptr) {
1071 log_info(class, preload)("Preloading of class %s during linking of class %s "
1072 "(cause: LoadableDescriptors attribute) succeeded",
1073 class_name->as_C_string(), ik->name()->as_C_string());
1074 if (!klass->is_inline_klass()) {
1075 // Non value class are allowed by the current spec, but it could be an indication
1076 // of an issue so let's log a warning
1077 log_info(class, preload)("Preloading of class %s during linking of class %s "
1078 "(cause: LoadableDescriptors attribute) but loaded class is not a value class",
1079 class_name->as_C_string(), ik->name()->as_C_string());
1080 }
1081 } else {
1082 log_info(class, preload)("Preloading of class %s during linking of class %s "
1083 "(cause: LoadableDescriptors attribute) failed",
1084 class_name->as_C_string(), ik->name()->as_C_string());
1085 }
1086 }
1087 }
1088 }
1089
1090 void InstanceKlass::link_class(TRAPS) {
1091 assert(is_loaded(), "must be loaded");
1092 if (!is_linked()) {
1093 link_class_impl(CHECK);
1094 }
1095 }
1096
1097 // Called to verify that a class can link during initialization, without
1098 // throwing a VerifyError.
1099 bool InstanceKlass::link_class_or_fail(TRAPS) {
1100 assert(is_loaded(), "must be loaded");
1101 if (!is_linked()) {
1102 link_class_impl(CHECK_false);
1103 }
1104 return is_linked();
1105 }
1106
1107 bool InstanceKlass::link_class_impl(TRAPS) {
1108 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
1109 // This is for CDS static dump only -- we use the in_error_state to indicate that
1110 // the class has failed verification. Throwing the NoClassDefFoundError here is just
1111 // a convenient way to stop repeat attempts to verify the same (bad) class.
1112 //
1113 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
1114 // if we are executing Java code. This is not a problem for CDS dumping phase since
1115 // it doesn't execute any Java code.
1116 ResourceMark rm(THREAD);
1117 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1118 Exceptions::fthrow(THREAD_AND_LOCATION,
1119 vmSymbols::java_lang_NoClassDefFoundError(),
1120 "Class %s, or one of its supertypes, failed class initialization",
1121 external_name());
1122 return false;
1123 }
1124 // return if already verified
1125 if (is_linked()) {
1126 return true;
1127 }
1128
1129 // Timing
1130 // timer handles recursion
1131 JavaThread* jt = THREAD;
1132
1133 // link super class before linking this class
1134 InstanceKlass* super_klass = super();
1135 if (super_klass != nullptr) {
1136 if (super_klass->is_interface()) { // check if super class is an interface
1137 ResourceMark rm(THREAD);
1138 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1139 Exceptions::fthrow(
1140 THREAD_AND_LOCATION,
1141 vmSymbols::java_lang_IncompatibleClassChangeError(),
1142 "class %s has interface %s as super class",
1143 external_name(),
1144 super_klass->external_name()
1145 );
1146 return false;
1147 }
1148
1149 super_klass->link_class_impl(CHECK_false);
1150 }
1151
1152 // link all interfaces implemented by this class before linking this class
1153 Array<InstanceKlass*>* interfaces = local_interfaces();
1154 int num_interfaces = interfaces->length();
1155 for (int index = 0; index < num_interfaces; index++) {
1156 InstanceKlass* interk = interfaces->at(index);
1157 interk->link_class_impl(CHECK_false);
1158 }
1159
1160 if (Arguments::is_valhalla_enabled()) {
1161 // Aggressively preloading all classes from the LoadableDescriptors attribute
1162 // so inline classes can be scalarized in the calling conventions computed below
1163 load_classes_from_loadable_descriptors_attribute(this, THREAD);
1164 assert(!HAS_PENDING_EXCEPTION, "Shouldn't have pending exceptions from call above");
1165 }
1166
1167 // in case the class is linked in the process of linking its superclasses
1168 if (is_linked()) {
1169 return true;
1170 }
1171
1172 // trace only the link time for this klass that includes
1173 // the verification time
1174 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1175 ClassLoader::perf_class_link_selftime(),
1176 ClassLoader::perf_classes_linked(),
1177 jt->get_thread_stat()->perf_recursion_counts_addr(),
1178 jt->get_thread_stat()->perf_timers_addr(),
1179 PerfClassTraceTime::CLASS_LINK);
1180
1181 // verification & rewriting
1182 {
1183 HandleMark hm(THREAD);
1184 Handle h_init_lock(THREAD, init_lock());
1185 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false);
1186 // Don't allow preemption if we link/initialize classes below,
1187 // since that would release this monitor while we are in the
1188 // middle of linking this class.
1189 NoPreemptMark npm(THREAD);
1190
1191 // rewritten will have been set if loader constraint error found
1192 // on an earlier link attempt
1193 // don't verify or rewrite if already rewritten
1194 //
1195
1196 if (!is_linked()) {
1197 if (!is_rewritten()) {
1198 if (in_aot_cache()) {
1199 assert(!verified_at_dump_time(), "must be");
1200 }
1201 {
1202 bool verify_ok = verify_code(THREAD);
1203 if (!verify_ok) {
1204 return false;
1205 }
1206 }
1207
1208 // Just in case a side-effect of verify linked this class already
1209 // (which can sometimes happen since the verifier loads classes
1210 // using custom class loaders, which are free to initialize things)
1211 if (is_linked()) {
1212 return true;
1213 }
1214
1215 // also sets rewritten
1216 rewrite_class(CHECK_false);
1217 } else if (in_aot_cache()) {
1218 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1219 }
1220
1221 // relocate jsrs and link methods after they are all rewritten
1222 link_methods(CHECK_false);
1223
1224 // Initialize the vtable and interface table after
1225 // methods have been rewritten since rewrite may
1226 // fabricate new Method*s.
1227 // also does loader constraint checking
1228 //
1229 // initialize_vtable and initialize_itable need to be rerun
1230 // for a shared class if
1231 // 1) the class is loaded by custom class loader or
1232 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1233 // 3) the class was not verified during dump time
1234 bool need_init_table = true;
1235 if (in_aot_cache() && verified_at_dump_time() &&
1236 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1237 need_init_table = false;
1238 }
1239 if (need_init_table) {
1240 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1241 itable().initialize_itable_and_check_constraints(CHECK_false);
1242 }
1243 #ifdef ASSERT
1244 vtable().verify(tty, true);
1245 // In case itable verification is ever added.
1246 // itable().verify(tty, true);
1247 #endif
1248 if (Universe::is_fully_initialized()) {
1249 DeoptimizationScope deopt_scope;
1250 {
1251 // Now mark all code that assumes the class is not linked.
1252 // Set state under the Compile_lock also.
1253 MutexLocker ml(THREAD, Compile_lock);
1254
1255 set_init_state(linked);
1256 CodeCache::mark_dependents_on(&deopt_scope, this);
1257 }
1258 // Perform the deopt handshake outside Compile_lock.
1259 deopt_scope.deoptimize_marked();
1260 } else {
1261 set_init_state(linked);
1262 }
1263 if (JvmtiExport::should_post_class_prepare()) {
1264 JvmtiExport::post_class_prepare(THREAD, this);
1265 }
1266 }
1267 }
1268 return true;
1269 }
1270
1271 // Rewrite the byte codes of all of the methods of a class.
1272 // The rewriter must be called exactly once. Rewriting must happen after
1273 // verification but before the first method of the class is executed.
1274 void InstanceKlass::rewrite_class(TRAPS) {
1275 assert(is_loaded(), "must be loaded");
1276 if (is_rewritten()) {
1277 assert(in_aot_cache(), "rewriting an unshared class?");
1278 return;
1279 }
1280 Rewriter::rewrite(this, CHECK);
1281 set_rewritten();
1282 }
1283
1284 // Now relocate and link method entry points after class is rewritten.
1285 // This is outside is_rewritten flag. In case of an exception, it can be
1286 // executed more than once.
1287 void InstanceKlass::link_methods(TRAPS) {
1288 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1289
1290 int len = methods()->length();
1291 for (int i = len-1; i >= 0; i--) {
1292 methodHandle m(THREAD, methods()->at(i));
1293
1294 // Set up method entry points for compiler and interpreter .
1295 m->link_method(m, CHECK);
1296 }
1297 }
1298
1299 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1300 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1301 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1302 for (int i = 0; i < local_interfaces()->length(); ++i) {
1303 InstanceKlass* ik = local_interfaces()->at(i);
1304
1305 // Initialization is depth first search ie. we start with top of the inheritance tree
1306 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1307 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1308 if (ik->has_nonstatic_concrete_methods()) {
1309 ik->initialize_super_interfaces(CHECK);
1310 }
1311
1312 // Only initialize() interfaces that "declare" concrete methods.
1313 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1314 ik->initialize(CHECK);
1315 }
1316 }
1317 }
1318
1319 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1320 static InitializationErrorTable* _initialization_error_table;
1321
1322 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1323 // Create the same exception with a message indicating the thread name,
1324 // and the StackTraceElements.
1325 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1326 ResourceMark rm(current);
1327 if (init_error.is_null()) {
1328 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1329
1330 // We failed to create the new exception, most likely due to either out-of-memory or
1331 // a stackoverflow error. If the original exception was either of those then we save
1332 // the shared, pre-allocated, stackless, instance of that exception.
1333 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1334 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1335 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1336 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1337 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1338 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1339 } else {
1340 return;
1341 }
1342 }
1343
1344 MutexLocker ml(current, ClassInitError_lock);
1345 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1346 bool created;
1347 if (_initialization_error_table == nullptr) {
1348 _initialization_error_table = new (mtClass) InitializationErrorTable();
1349 }
1350 _initialization_error_table->put_if_absent(this, elem, &created);
1351 assert(created, "Initialization is single threaded");
1352 log_trace(class, init)("Initialization error added for class %s", external_name());
1353 }
1354
1355 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1356 MutexLocker ml(current, ClassInitError_lock);
1357 if (_initialization_error_table == nullptr) {
1358 return nullptr;
1359 }
1360 OopHandle* h = _initialization_error_table->get(this);
1361 return (h != nullptr) ? h->resolve() : nullptr;
1362 }
1363
1364 // Need to remove entries for unloaded classes.
1365 void InstanceKlass::clean_initialization_error_table() {
1366 struct InitErrorTableCleaner {
1367 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1368 if (!ik->is_loader_alive()) {
1369 h.release(Universe::vm_global());
1370 return true;
1371 } else {
1372 return false;
1373 }
1374 }
1375 };
1376
1377 assert_locked_or_safepoint(ClassInitError_lock);
1378 InitErrorTableCleaner cleaner;
1379 if (_initialization_error_table != nullptr) {
1380 _initialization_error_table->unlink(&cleaner);
1381 }
1382 }
1383
1384 class ThreadWaitingForClassInit : public StackObj {
1385 JavaThread* _thread;
1386 public:
1387 ThreadWaitingForClassInit(JavaThread* thread, InstanceKlass* ik) : _thread(thread) {
1388 _thread->set_class_to_be_initialized(ik);
1389 }
1390 ~ThreadWaitingForClassInit() {
1391 _thread->set_class_to_be_initialized(nullptr);
1392 }
1393 };
1394
1395 void InstanceKlass::initialize_impl(TRAPS) {
1396 HandleMark hm(THREAD);
1397
1398 // Make sure klass is linked (verified) before initialization
1399 // A class could already be verified, since it has been reflected upon.
1400 link_class(CHECK);
1401
1402 DTRACE_CLASSINIT_PROBE(required, -1);
1403
1404 bool wait = false;
1405
1406 JavaThread* jt = THREAD;
1407
1408 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1409
1410 // refer to the JVM book page 47 for description of steps
1411 // Step 1
1412 {
1413 Handle h_init_lock(THREAD, init_lock());
1414 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE);
1415
1416 // Step 2
1417 // If we were to use wait() instead of waitInterruptibly() then
1418 // we might end up throwing IE from link/symbol resolution sites
1419 // that aren't expected to throw. This would wreak havoc. See 6320309.
1420 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1421 if (debug_logging_enabled) {
1422 ResourceMark rm(jt);
1423 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1424 jt->name(), external_name(), init_thread_name());
1425 }
1426 wait = true;
1427 ThreadWaitingForClassInit twcl(THREAD, this);
1428 ol.wait_uninterruptibly(CHECK_PREEMPTABLE);
1429 }
1430
1431 // Step 3
1432 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1433 if (debug_logging_enabled) {
1434 ResourceMark rm(jt);
1435 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1436 jt->name(), external_name());
1437 }
1438 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1439 return;
1440 }
1441
1442 // Step 4
1443 if (is_initialized()) {
1444 if (debug_logging_enabled) {
1445 ResourceMark rm(jt);
1446 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1447 jt->name(), external_name());
1448 }
1449 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1450 return;
1451 }
1452
1453 // Step 5
1454 if (is_in_error_state()) {
1455 if (debug_logging_enabled) {
1456 ResourceMark rm(jt);
1457 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1458 jt->name(), external_name());
1459 }
1460
1461 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1462 ResourceMark rm(THREAD);
1463 Handle cause(THREAD, get_initialization_error(THREAD));
1464
1465 stringStream ss;
1466 ss.print("Could not initialize class %s", external_name());
1467 if (cause.is_null()) {
1468 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1469 } else {
1470 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1471 ss.as_string(), cause);
1472 }
1473 } else {
1474
1475 // Step 6
1476 set_init_state(being_initialized);
1477 set_init_thread(jt);
1478 if (debug_logging_enabled) {
1479 ResourceMark rm(jt);
1480 log_debug(class, init)("Thread \"%s\" is initializing %s",
1481 jt->name(), external_name());
1482 }
1483 }
1484 }
1485
1486 // Block preemption once we are the initializer thread. Unmounting now
1487 // would complicate the reentrant case (identity is platform thread).
1488 NoPreemptMark npm(THREAD);
1489
1490 // Pre-allocating an all-zero value to be used to reset nullable flat storages
1491 if (is_inline_klass()) {
1492 InlineKlass* vk = InlineKlass::cast(this);
1493 if (vk->supports_nullable_layouts()) {
1494 oop val = vk->allocate_instance(THREAD);
1495 if (HAS_PENDING_EXCEPTION) {
1496 Handle e(THREAD, PENDING_EXCEPTION);
1497 CLEAR_PENDING_EXCEPTION;
1498 {
1499 EXCEPTION_MARK;
1500 add_initialization_error(THREAD, e);
1501 // Locks object, set state, and notify all waiting threads
1502 set_initialization_state_and_notify(initialization_error, THREAD);
1503 CLEAR_PENDING_EXCEPTION;
1504 }
1505 THROW_OOP(e());
1506 }
1507 vk->set_null_reset_value(val);
1508 }
1509 }
1510
1511 // Step 7
1512 // Next, if C is a class rather than an interface, initialize it's super class and super
1513 // interfaces.
1514 if (!is_interface()) {
1515 Klass* super_klass = super();
1516 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1517 super_klass->initialize(THREAD);
1518 }
1519 // If C implements any interface that declares a non-static, concrete method,
1520 // the initialization of C triggers initialization of its super interfaces.
1521 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1522 // having a superinterface that declares, non-static, concrete methods
1523 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1524 initialize_super_interfaces(THREAD);
1525 }
1526
1527 // If any exceptions, complete abruptly, throwing the same exception as above.
1528 if (HAS_PENDING_EXCEPTION) {
1529 Handle e(THREAD, PENDING_EXCEPTION);
1530 CLEAR_PENDING_EXCEPTION;
1531 {
1532 EXCEPTION_MARK;
1533 add_initialization_error(THREAD, e);
1534 // Locks object, set state, and notify all waiting threads
1535 set_initialization_state_and_notify(initialization_error, THREAD);
1536 CLEAR_PENDING_EXCEPTION;
1537 }
1538 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1539 THROW_OOP(e());
1540 }
1541 }
1542
1543 // Step 8
1544 {
1545 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1546 if (class_initializer() != nullptr) {
1547 // Timer includes any side effects of class initialization (resolution,
1548 // etc), but not recursive entry into call_class_initializer().
1549 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1550 ClassLoader::perf_class_init_selftime(),
1551 ClassLoader::perf_classes_inited(),
1552 jt->get_thread_stat()->perf_recursion_counts_addr(),
1553 jt->get_thread_stat()->perf_timers_addr(),
1554 PerfClassTraceTime::CLASS_CLINIT);
1555 call_class_initializer(THREAD);
1556 } else {
1557 // The elapsed time is so small it's not worth counting.
1558 if (UsePerfData) {
1559 ClassLoader::perf_classes_inited()->inc();
1560 }
1561 call_class_initializer(THREAD);
1562 }
1563
1564 if (has_strict_static_fields() && !HAS_PENDING_EXCEPTION) {
1565 // Step 9 also verifies that strict static fields have been initialized.
1566 // Status bits were set in ClassFileParser::post_process_parsed_stream.
1567 // After <clinit>, bits must all be clear, or else we must throw an error.
1568 // This is an extremely fast check, so we won't bother with a timer.
1569 assert(fields_status() != nullptr, "");
1570 Symbol* bad_strict_static = nullptr;
1571 for (int index = 0; index < fields_status()->length(); index++) {
1572 // Very fast loop over single byte array looking for a set bit.
1573 if (fields_status()->adr_at(index)->is_strict_static_unset()) {
1574 // This strict static field has not been set by the class initializer.
1575 // Note that in the common no-error case, we read no field metadata.
1576 // We only unpack it when we need to report an error.
1577 FieldInfo fi = field(index);
1578 bad_strict_static = fi.name(constants());
1579 if (debug_logging_enabled) {
1580 ResourceMark rm(jt);
1581 const char* msg = format_strict_static_message(bad_strict_static);
1582 log_debug(class, init)("%s", msg);
1583 } else {
1584 // If we are not logging, do not bother to look for a second offense.
1585 break;
1586 }
1587 }
1588 }
1589 if (bad_strict_static != nullptr) {
1590 throw_strict_static_exception(bad_strict_static, "is unset after initialization of", THREAD);
1591 }
1592 }
1593 }
1594
1595 // Step 9
1596 if (!HAS_PENDING_EXCEPTION) {
1597 set_initialization_state_and_notify(fully_initialized, CHECK);
1598 DEBUG_ONLY(vtable().verify(tty, true);)
1599 CompilationPolicy::replay_training_at_init(this, THREAD);
1600 }
1601 else {
1602 // Step 10 and 11
1603 Handle e(THREAD, PENDING_EXCEPTION);
1604 CLEAR_PENDING_EXCEPTION;
1605 // JVMTI has already reported the pending exception
1606 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1607 JvmtiExport::clear_detected_exception(jt);
1608 {
1609 EXCEPTION_MARK;
1610 add_initialization_error(THREAD, e);
1611 set_initialization_state_and_notify(initialization_error, THREAD);
1612 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1613 // JVMTI has already reported the pending exception
1614 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1615 JvmtiExport::clear_detected_exception(jt);
1616 }
1617 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1618 if (e->is_a(vmClasses::Error_klass())) {
1619 THROW_OOP(e());
1620 } else {
1621 JavaCallArguments args(e);
1622 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1623 vmSymbols::throwable_void_signature(),
1624 &args);
1625 }
1626 }
1627 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1628 }
1629
1630
1631 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1632 Handle h_init_lock(THREAD, init_lock());
1633 if (h_init_lock() != nullptr) {
1634 ObjectLocker ol(h_init_lock, THREAD);
1635 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1636 set_init_state(state);
1637 fence_and_clear_init_lock();
1638 ol.notify_all(CHECK);
1639 } else {
1640 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1641 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1642 set_init_state(state);
1643 }
1644 }
1645
1646 void InstanceKlass::notify_strict_static_access(int field_index, bool is_writing, TRAPS) {
1647 guarantee(field_index >= 0 && field_index < fields_status()->length(), "valid field index");
1648 DEBUG_ONLY(FieldInfo debugfi = field(field_index));
1649 assert(debugfi.access_flags().is_strict(), "");
1650 assert(debugfi.access_flags().is_static(), "");
1651 FieldStatus& fs = *fields_status()->adr_at(field_index);
1652 LogTarget(Trace, class, init) lt;
1653 if (lt.is_enabled()) {
1654 ResourceMark rm(THREAD);
1655 LogStream ls(lt);
1656 FieldInfo fi = field(field_index);
1657 ls.print("notify %s %s %s%s ",
1658 external_name(), is_writing? "Write" : "Read",
1659 fs.is_strict_static_unset() ? "Unset" : "(set)",
1660 fs.is_strict_static_unread() ? "+Unread" : "");
1661 fi.print(&ls, constants());
1662 }
1663 if (fs.is_strict_static_unset()) {
1664 assert(fs.is_strict_static_unread(), "ClassFileParser resp.");
1665 // If it is not set, there are only two reasonable things we can do here:
1666 // - mark it set if this is putstatic
1667 // - throw an error (Read-Before-Write) if this is getstatic
1668
1669 // The unset state is (or should be) transient, and observable only in one
1670 // thread during the execution of <clinit>. Something is wrong here as this
1671 // should not be possible
1672 guarantee(is_reentrant_initialization(THREAD), "unscoped access to strict static");
1673 if (is_writing) {
1674 // clear the "unset" bit, since the field is actually going to be written
1675 fs.update_strict_static_unset(false);
1676 } else {
1677 // throw an IllegalStateException, since we are reading before writing
1678 // see also InstanceKlass::initialize_impl, Step 8 (at end)
1679 Symbol* bad_strict_static = field(field_index).name(constants());
1680 throw_strict_static_exception(bad_strict_static, "is unset before first read in", CHECK);
1681 }
1682 } else {
1683 // Ensure no write after read for final strict statics
1684 FieldInfo fi = field(field_index);
1685 bool is_final = fi.access_flags().is_final();
1686 if (is_final) {
1687 // no final write after read, so observing a constant freezes it, as if <clinit> ended early
1688 // (maybe we could trust the constant a little earlier, before <clinit> ends)
1689 if (is_writing && !fs.is_strict_static_unread()) {
1690 Symbol* bad_strict_static = fi.name(constants());
1691 throw_strict_static_exception(bad_strict_static, "is set after read (as final) in", CHECK);
1692 } else if (!is_writing && fs.is_strict_static_unread()) {
1693 fs.update_strict_static_unread(false);
1694 }
1695 }
1696 }
1697 }
1698
1699 void InstanceKlass::throw_strict_static_exception(Symbol* field_name, const char* when, TRAPS) {
1700 ResourceMark rm(THREAD);
1701 const char* msg = format_strict_static_message(field_name, when);
1702 THROW_MSG(vmSymbols::java_lang_IllegalStateException(), msg);
1703 }
1704
1705 const char* InstanceKlass::format_strict_static_message(Symbol* field_name, const char* when) {
1706 stringStream ss;
1707 ss.print("Strict static \"%s\" %s %s",
1708 field_name->as_C_string(),
1709 when == nullptr ? "is unset in" : when,
1710 external_name());
1711 return ss.as_string();
1712 }
1713
1714 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1715 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1716 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1717 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1718
1719 DeoptimizationScope deopt_scope;
1720 {
1721 MutexLocker ml(current, Compile_lock);
1722
1723 set_init_state(InstanceKlass::loaded);
1724 // make sure init_state store is already done.
1725 // The compiler reads the hierarchy outside of the Compile_lock.
1726 // Access ordering is used to add to hierarchy.
1727
1728 // Link into hierarchy.
1729 append_to_sibling_list(); // add to superklass/sibling list
1730 process_interfaces(); // handle all "implements" declarations
1731
1732 // Now mark all code that depended on old class hierarchy.
1733 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1734 if (Universe::is_fully_initialized()) {
1735 CodeCache::mark_dependents_on(&deopt_scope, this);
1736 }
1737 }
1738 // Perform the deopt handshake outside Compile_lock.
1739 deopt_scope.deoptimize_marked();
1740 }
1741
1742
1743 InstanceKlass* InstanceKlass::implementor() const {
1744 InstanceKlass* volatile* ik = adr_implementor();
1745 if (ik == nullptr) {
1746 return nullptr;
1747 } else {
1748 // This load races with inserts, and therefore needs acquire.
1749 InstanceKlass* ikls = AtomicAccess::load_acquire(ik);
1750 if (ikls != nullptr && !ikls->is_loader_alive()) {
1751 return nullptr; // don't return unloaded class
1752 } else {
1753 return ikls;
1754 }
1755 }
1756 }
1757
1758
1759 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1760 assert_locked_or_safepoint(Compile_lock);
1761 assert(is_interface(), "not interface");
1762 InstanceKlass* volatile* addr = adr_implementor();
1763 assert(addr != nullptr, "null addr");
1764 if (addr != nullptr) {
1765 AtomicAccess::release_store(addr, ik);
1766 }
1767 }
1768
1769 int InstanceKlass::nof_implementors() const {
1770 InstanceKlass* ik = implementor();
1771 if (ik == nullptr) {
1772 return 0;
1773 } else if (ik != this) {
1774 return 1;
1775 } else {
1776 return 2;
1777 }
1778 }
1779
1780 // The embedded _implementor field can only record one implementor.
1781 // When there are more than one implementors, the _implementor field
1782 // is set to the interface Klass* itself. Following are the possible
1783 // values for the _implementor field:
1784 // null - no implementor
1785 // implementor Klass* - one implementor
1786 // self - more than one implementor
1787 //
1788 // The _implementor field only exists for interfaces.
1789 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1790 if (Universe::is_fully_initialized()) {
1791 assert_lock_strong(Compile_lock);
1792 }
1793 assert(is_interface(), "not interface");
1794 // Filter out my subinterfaces.
1795 // (Note: Interfaces are never on the subklass list.)
1796 if (ik->is_interface()) return;
1797
1798 // Filter out subclasses whose supers already implement me.
1799 // (Note: CHA must walk subclasses of direct implementors
1800 // in order to locate indirect implementors.)
1801 InstanceKlass* super_ik = ik->super();
1802 if (super_ik != nullptr && super_ik->implements_interface(this))
1803 // We only need to check one immediate superclass, since the
1804 // implements_interface query looks at transitive_interfaces.
1805 // Any supers of the super have the same (or fewer) transitive_interfaces.
1806 return;
1807
1808 InstanceKlass* iklass = implementor();
1809 if (iklass == nullptr) {
1810 set_implementor(ik);
1811 } else if (iklass != this && iklass != ik) {
1812 // There is already an implementor. Use itself as an indicator of
1813 // more than one implementors.
1814 set_implementor(this);
1815 }
1816
1817 // The implementor also implements the transitive_interfaces
1818 for (int index = 0; index < local_interfaces()->length(); index++) {
1819 local_interfaces()->at(index)->add_implementor(ik);
1820 }
1821 }
1822
1823 void InstanceKlass::init_implementor() {
1824 if (is_interface()) {
1825 set_implementor(nullptr);
1826 }
1827 }
1828
1829
1830 void InstanceKlass::process_interfaces() {
1831 // link this class into the implementors list of every interface it implements
1832 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1833 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1834 InstanceKlass* interf = local_interfaces()->at(i);
1835 assert(interf->is_interface(), "expected interface");
1836 interf->add_implementor(this);
1837 }
1838 }
1839
1840 bool InstanceKlass::can_be_primary_super_slow() const {
1841 if (is_interface())
1842 return false;
1843 else
1844 return Klass::can_be_primary_super_slow();
1845 }
1846
1847 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1848 Array<InstanceKlass*>* transitive_interfaces) {
1849 // The secondaries are the implemented interfaces.
1850 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1851 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1852 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1853 int num_secondaries = num_extra_slots + interfaces->length();
1854 if (num_secondaries == 0) {
1855 // Must share this for correct bootstrapping!
1856 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1857 return nullptr;
1858 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1859 // We will reuse the transitive interfaces list if we're certain
1860 // it's in hash order.
1861 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1862 set_secondary_supers(interfaces, bitmap);
1863 return nullptr;
1864 }
1865 // Copy transitive interfaces to a temporary growable array to be constructed
1866 // into the secondary super list with extra slots.
1867 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1868 for (int i = 0; i < interfaces->length(); i++) {
1869 secondaries->push(interfaces->at(i));
1870 }
1871 return secondaries;
1872 }
1873
1874 bool InstanceKlass::implements_interface(Klass* k) const {
1875 if (this == k) return true;
1876 assert(k->is_interface(), "should be an interface class");
1877 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1878 if (transitive_interfaces()->at(i) == k) {
1879 return true;
1880 }
1881 }
1882 return false;
1883 }
1884
1885 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1886 // Verify direct super interface
1887 if (this == k) return true;
1888 assert(k->is_interface(), "should be an interface class");
1889 for (int i = 0; i < local_interfaces()->length(); i++) {
1890 if (local_interfaces()->at(i) == k) {
1891 return true;
1892 }
1893 }
1894 return false;
1895 }
1896
1897 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1898 if (TraceFinalizerRegistration) {
1899 tty->print("Registered ");
1900 i->print_value_on(tty);
1901 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1902 }
1903 instanceHandle h_i(THREAD, i);
1904 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1905 JavaValue result(T_VOID);
1906 JavaCallArguments args(h_i);
1907 methodHandle mh(THREAD, Universe::finalizer_register_method());
1908 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1909 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1910 return h_i();
1911 }
1912
1913 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1914 assert(!is_abstract() && !is_interface(), "Should not create this object");
1915 size_t size = size_helper(); // Query before forming handle.
1916 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1917 }
1918
1919 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1920 Klass* k = java_lang_Class::as_Klass(java_class);
1921 if (k == nullptr) {
1922 ResourceMark rm(THREAD);
1923 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1924 }
1925 InstanceKlass* ik = cast(k);
1926 ik->check_valid_for_instantiation(false, CHECK_NULL);
1927 ik->initialize(CHECK_NULL);
1928 return ik->allocate_instance(THREAD);
1929 }
1930
1931 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1932 return instanceHandle(THREAD, allocate_instance(THREAD));
1933 }
1934
1935 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1936 if (is_interface() || is_abstract()) {
1937 ResourceMark rm(THREAD);
1938 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1939 : vmSymbols::java_lang_InstantiationException(), external_name());
1940 }
1941 if (this == vmClasses::Class_klass()) {
1942 ResourceMark rm(THREAD);
1943 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1944 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1945 }
1946 }
1947
1948 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1949 // Need load-acquire for lock-free read
1950 if (array_klasses_acquire() == nullptr) {
1951
1952 // Recursively lock array allocation
1953 RecursiveLocker rl(MultiArray_lock, THREAD);
1954
1955 // Check if another thread created the array klass while we were waiting for the lock.
1956 if (array_klasses() == nullptr) {
1957 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1958 // use 'release' to pair with lock-free load
1959 release_set_array_klasses(k);
1960 }
1961 }
1962
1963 // array_klasses() will always be set at this point
1964 ArrayKlass* ak = array_klasses();
1965 assert(ak != nullptr, "should be set");
1966 return ak->array_klass(n, THREAD);
1967 }
1968
1969 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1970 // Need load-acquire for lock-free read
1971 ArrayKlass* ak = array_klasses_acquire();
1972 if (ak == nullptr) {
1973 return nullptr;
1974 } else {
1975 return ak->array_klass_or_null(n);
1976 }
1977 }
1978
1979 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1980 return array_klass(1, THREAD);
1981 }
1982
1983 ArrayKlass* InstanceKlass::array_klass_or_null() {
1984 return array_klass_or_null(1);
1985 }
1986
1987 static int call_class_initializer_counter = 0; // for debugging
1988
1989 Method* InstanceKlass::class_initializer() const {
1990 Method* clinit = find_method(
1991 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1992 if (clinit != nullptr && clinit->is_class_initializer()) {
1993 return clinit;
1994 }
1995 return nullptr;
1996 }
1997
1998 void InstanceKlass::call_class_initializer(TRAPS) {
1999 if (ReplayCompiles &&
2000 (ReplaySuppressInitializers == 1 ||
2001 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
2002 // Hide the existence of the initializer for the purpose of replaying the compile
2003 return;
2004 }
2005
2006 #if INCLUDE_CDS
2007 // This is needed to ensure the consistency of the archived heap objects.
2008 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
2009 AOTClassInitializer::call_runtime_setup(THREAD, this);
2010 return;
2011 } else if (has_archived_enum_objs()) {
2012 assert(in_aot_cache(), "must be");
2013 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
2014 if (initialized) {
2015 return;
2016 }
2017 }
2018 #endif
2019
2020 methodHandle h_method(THREAD, class_initializer());
2021 assert(!is_initialized(), "we cannot initialize twice");
2022 LogTarget(Info, class, init) lt;
2023 if (lt.is_enabled()) {
2024 ResourceMark rm(THREAD);
2025 LogStream ls(lt);
2026 ls.print("%d Initializing ", call_class_initializer_counter++);
2027 name()->print_value_on(&ls);
2028 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
2029 h_method() == nullptr ? "(no method)" : "", p2i(this),
2030 THREAD->name());
2031 }
2032 if (h_method() != nullptr) {
2033 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
2034 JavaCallArguments args; // No arguments
2035 JavaValue result(T_VOID);
2036 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
2037 }
2038 }
2039
2040 // If a class that implements this interface is initialized, is the JVM required
2041 // to first execute a <clinit> method declared in this interface,
2042 // or (if also_check_supers==true) any of the super types of this interface?
2043 //
2044 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
2045 // an interface, then let SC be its superclass and let SI1, ..., SIn
2046 // be all superinterfaces of C (whether direct or indirect) that
2047 // declare at least one non-abstract, non-static method.
2048 //
2049 // So when an interface is initialized, it does not look at its
2050 // supers. But a proper class will ensure that all of its supers have
2051 // run their <clinit> methods, except that it disregards interfaces
2052 // that lack a non-static concrete method (i.e., a default method).
2053 // Therefore, you should probably call this method only when the
2054 // current class is a super of some proper class, not an interface.
2055 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
2056 assert(is_interface(), "must be");
2057
2058 if (!has_nonstatic_concrete_methods()) {
2059 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
2060 return false;
2061 }
2062
2063 // JVMS 5.5. Initialization
2064 // ...If C is an interface that declares a non-abstract,
2065 // non-static method, the initialization of a class that
2066 // implements C directly or indirectly.
2067 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
2068 return true;
2069 }
2070 if (also_check_supers) {
2071 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2072 for (int i = 0; i < all_ifs->length(); ++i) {
2073 InstanceKlass* super_intf = all_ifs->at(i);
2074 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
2075 return true;
2076 }
2077 }
2078 }
2079 return false;
2080 }
2081
2082 void InstanceKlass::mask_for(const methodHandle& method, int bci,
2083 InterpreterOopMap* entry_for) {
2084 // Lazily create the _oop_map_cache at first request.
2085 // Load_acquire is needed to safely get instance published with CAS by another thread.
2086 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache);
2087 if (oop_map_cache == nullptr) {
2088 // Try to install new instance atomically.
2089 oop_map_cache = new OopMapCache();
2090 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
2091 if (other != nullptr) {
2092 // Someone else managed to install before us, ditch local copy and use the existing one.
2093 delete oop_map_cache;
2094 oop_map_cache = other;
2095 }
2096 }
2097 // _oop_map_cache is constant after init; lookup below does its own locking.
2098 oop_map_cache->lookup(method, bci, entry_for);
2099 }
2100
2101
2102 FieldInfo InstanceKlass::field(int index) const {
2103 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2104 if (fs.index() == index) {
2105 return fs.to_FieldInfo();
2106 }
2107 }
2108 fatal("Field not found");
2109 return FieldInfo();
2110 }
2111
2112 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2113 JavaFieldStream fs(this);
2114 if (fs.lookup(name, sig)) {
2115 assert(fs.name() == name, "name must match");
2116 assert(fs.signature() == sig, "signature must match");
2117 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2118 return true;
2119 }
2120 return false;
2121 }
2122
2123
2124 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2125 const int n = local_interfaces()->length();
2126 for (int i = 0; i < n; i++) {
2127 InstanceKlass* intf1 = local_interfaces()->at(i);
2128 assert(intf1->is_interface(), "just checking type");
2129 // search for field in current interface
2130 if (intf1->find_local_field(name, sig, fd)) {
2131 assert(fd->is_static(), "interface field must be static");
2132 return intf1;
2133 }
2134 // search for field in direct superinterfaces
2135 Klass* intf2 = intf1->find_interface_field(name, sig, fd);
2136 if (intf2 != nullptr) return intf2;
2137 }
2138 // otherwise field lookup fails
2139 return nullptr;
2140 }
2141
2142
2143 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
2144 // search order according to newest JVM spec (5.4.3.2, p.167).
2145 // 1) search for field in current klass
2146 if (find_local_field(name, sig, fd)) {
2147 return const_cast<InstanceKlass*>(this);
2148 }
2149 // 2) search for field recursively in direct superinterfaces
2150 { Klass* intf = find_interface_field(name, sig, fd);
2151 if (intf != nullptr) return intf;
2152 }
2153 // 3) apply field lookup recursively if superclass exists
2154 { InstanceKlass* supr = super();
2155 if (supr != nullptr) return supr->find_field(name, sig, fd);
2156 }
2157 // 4) otherwise field lookup fails
2158 return nullptr;
2159 }
2160
2161
2162 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
2163 // search order according to newest JVM spec (5.4.3.2, p.167).
2164 // 1) search for field in current klass
2165 if (find_local_field(name, sig, fd)) {
2166 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
2167 }
2168 // 2) search for field recursively in direct superinterfaces
2169 if (is_static) {
2170 Klass* intf = find_interface_field(name, sig, fd);
2171 if (intf != nullptr) return intf;
2172 }
2173 // 3) apply field lookup recursively if superclass exists
2174 { InstanceKlass* supr = super();
2175 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd);
2176 }
2177 // 4) otherwise field lookup fails
2178 return nullptr;
2179 }
2180
2181 bool InstanceKlass::contains_field_offset(int offset) {
2182 if (this->is_inline_klass()) {
2183 InlineKlass* vk = InlineKlass::cast(this);
2184 return offset >= vk->payload_offset() && offset < (vk->payload_offset() + vk->payload_size_in_bytes());
2185 } else {
2186 fieldDescriptor fd;
2187 return find_field_from_offset(offset, false, &fd);
2188 }
2189 }
2190
2191 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2192 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2193 if (fs.offset() == offset) {
2194 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2195 if (fd->is_static() == is_static) return true;
2196 }
2197 }
2198 return false;
2199 }
2200
2201 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
2202 const InstanceKlass* klass = this;
2203 while (klass != nullptr) {
2204 if (klass->find_local_field_from_offset(offset, is_static, fd)) {
2205 return true;
2206 }
2207 klass = klass->super();
2208 }
2209 return false;
2210 }
2211
2212 bool InstanceKlass::find_local_flat_field_containing_offset(int offset, fieldDescriptor* fd) const {
2213 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2214 if (!fs.is_flat()) {
2215 continue;
2216 }
2217
2218 if (fs.offset() > offset) {
2219 continue;
2220 }
2221
2222 const int offset_in_flat_field = offset - fs.offset();
2223 const InlineLayoutInfo layout_info = inline_layout_info(fs.index());
2224 const int field_size = layout_info.klass()->layout_size_in_bytes(layout_info.kind());
2225
2226 assert(LayoutKindHelper::is_flat(layout_info.kind()), "Must be flat");
2227
2228 if (offset_in_flat_field < field_size) {
2229 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
2230 assert(!fd->is_static(), "Static fields are not flattened");
2231
2232 return true;
2233 }
2234 }
2235
2236 return false;
2237 }
2238
2239 bool InstanceKlass::find_flat_field_containing_offset(int offset, fieldDescriptor* fd) const {
2240 const InstanceKlass* klass = this;
2241 while (klass != nullptr) {
2242 if (klass->find_local_flat_field_containing_offset(offset, fd)) {
2243 return true;
2244 }
2245
2246 klass = klass->super();
2247 }
2248
2249 return false;
2250 }
2251
2252 void InstanceKlass::methods_do(void f(Method* method)) {
2253 // Methods aren't stable until they are loaded. This can be read outside
2254 // a lock through the ClassLoaderData for profiling
2255 // Redefined scratch classes are on the list and need to be cleaned
2256 if (!is_loaded() && !is_scratch_class()) {
2257 return;
2258 }
2259
2260 int len = methods()->length();
2261 for (int index = 0; index < len; index++) {
2262 Method* m = methods()->at(index);
2263 assert(m->is_method(), "must be method");
2264 f(m);
2265 }
2266 }
2267
2268
2269 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2270 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2271 if (fs.access_flags().is_static()) {
2272 fieldDescriptor& fd = fs.field_descriptor();
2273 cl->do_field(&fd);
2274 }
2275 }
2276 }
2277
2278
2279 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2280 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2281 if (fs.access_flags().is_static()) {
2282 fieldDescriptor& fd = fs.field_descriptor();
2283 f(&fd, mirror, CHECK);
2284 }
2285 }
2286 }
2287
2288 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2289 InstanceKlass* super = this->super();
2290 if (super != nullptr) {
2291 super->do_nonstatic_fields(cl);
2292 }
2293 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2294 fieldDescriptor& fd = fs.field_descriptor();
2295 if (!fd.is_static()) {
2296 cl->do_field(&fd);
2297 }
2298 }
2299 }
2300
2301 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
2302 return a->offset() - b->offset();
2303 }
2304
2305 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2306 InstanceKlass* super = this->super();
2307 if (super != nullptr) {
2308 super->print_nonstatic_fields(cl);
2309 }
2310 ResourceMark rm;
2311 // In DebugInfo nonstatic fields are sorted by offset.
2312 GrowableArray<FieldInfo> fields_sorted;
2313 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2314 if (!fs.access_flags().is_static()) {
2315 fields_sorted.push(fs.to_FieldInfo());
2316 }
2317 }
2318 int length = fields_sorted.length();
2319 if (length > 0) {
2320 fields_sorted.sort(compare_fields_by_offset);
2321 fieldDescriptor fd;
2322 for (int i = 0; i < length; i++) {
2323 fd.reinitialize(this, fields_sorted.at(i));
2324 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
2325 cl->do_field(&fd);
2326 }
2327 }
2328 }
2329
2330 #ifdef ASSERT
2331 static int linear_search(const Array<Method*>* methods,
2332 const Symbol* name,
2333 const Symbol* signature) {
2334 const int len = methods->length();
2335 for (int index = 0; index < len; index++) {
2336 const Method* const m = methods->at(index);
2337 assert(m->is_method(), "must be method");
2338 if (m->signature() == signature && m->name() == name) {
2339 return index;
2340 }
2341 }
2342 return -1;
2343 }
2344 #endif
2345
2346 bool InstanceKlass::_disable_method_binary_search = false;
2347
2348 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2349 int len = methods->length();
2350 int l = 0;
2351 int h = len - 1;
2352 while (l <= h) {
2353 Method* m = methods->at(l);
2354 if (m->name() == name) {
2355 return l;
2356 }
2357 l++;
2358 }
2359 return -1;
2360 }
2361
2362 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2363 if (_disable_method_binary_search) {
2364 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2365 // At the final stage of dynamic dumping, the methods array may not be sorted
2366 // by ascending addresses of their names, so we can't use binary search anymore.
2367 // However, methods with the same name are still laid out consecutively inside the
2368 // methods array, so let's look for the first one that matches.
2369 return linear_search(methods, name);
2370 }
2371
2372 int len = methods->length();
2373 int l = 0;
2374 int h = len - 1;
2375
2376 // methods are sorted by ascending addresses of their names, so do binary search
2377 while (l <= h) {
2378 int mid = (l + h) >> 1;
2379 Method* m = methods->at(mid);
2380 assert(m->is_method(), "must be method");
2381 int res = m->name()->fast_compare(name);
2382 if (res == 0) {
2383 return mid;
2384 } else if (res < 0) {
2385 l = mid + 1;
2386 } else {
2387 h = mid - 1;
2388 }
2389 }
2390 return -1;
2391 }
2392
2393 // find_method looks up the name/signature in the local methods array
2394 Method* InstanceKlass::find_method(const Symbol* name,
2395 const Symbol* signature) const {
2396 return find_method_impl(name, signature,
2397 OverpassLookupMode::find,
2398 StaticLookupMode::find,
2399 PrivateLookupMode::find);
2400 }
2401
2402 Method* InstanceKlass::find_method_impl(const Symbol* name,
2403 const Symbol* signature,
2404 OverpassLookupMode overpass_mode,
2405 StaticLookupMode static_mode,
2406 PrivateLookupMode private_mode) const {
2407 return InstanceKlass::find_method_impl(methods(),
2408 name,
2409 signature,
2410 overpass_mode,
2411 static_mode,
2412 private_mode);
2413 }
2414
2415 // find_instance_method looks up the name/signature in the local methods array
2416 // and skips over static methods
2417 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2418 const Symbol* name,
2419 const Symbol* signature,
2420 PrivateLookupMode private_mode) {
2421 Method* const meth = InstanceKlass::find_method_impl(methods,
2422 name,
2423 signature,
2424 OverpassLookupMode::find,
2425 StaticLookupMode::skip,
2426 private_mode);
2427 assert(((meth == nullptr) || !meth->is_static()),
2428 "find_instance_method should have skipped statics");
2429 return meth;
2430 }
2431
2432 // find_instance_method looks up the name/signature in the local methods array
2433 // and skips over static methods
2434 Method* InstanceKlass::find_instance_method(const Symbol* name,
2435 const Symbol* signature,
2436 PrivateLookupMode private_mode) const {
2437 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2438 }
2439
2440 // Find looks up the name/signature in the local methods array
2441 // and filters on the overpass, static and private flags
2442 // This returns the first one found
2443 // note that the local methods array can have up to one overpass, one static
2444 // and one instance (private or not) with the same name/signature
2445 Method* InstanceKlass::find_local_method(const Symbol* name,
2446 const Symbol* signature,
2447 OverpassLookupMode overpass_mode,
2448 StaticLookupMode static_mode,
2449 PrivateLookupMode private_mode) const {
2450 return InstanceKlass::find_method_impl(methods(),
2451 name,
2452 signature,
2453 overpass_mode,
2454 static_mode,
2455 private_mode);
2456 }
2457
2458 // Find looks up the name/signature in the local methods array
2459 // and filters on the overpass, static and private flags
2460 // This returns the first one found
2461 // note that the local methods array can have up to one overpass, one static
2462 // and one instance (private or not) with the same name/signature
2463 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2464 const Symbol* name,
2465 const Symbol* signature,
2466 OverpassLookupMode overpass_mode,
2467 StaticLookupMode static_mode,
2468 PrivateLookupMode private_mode) {
2469 return InstanceKlass::find_method_impl(methods,
2470 name,
2471 signature,
2472 overpass_mode,
2473 static_mode,
2474 private_mode);
2475 }
2476
2477 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2478 const Symbol* name,
2479 const Symbol* signature) {
2480 return InstanceKlass::find_method_impl(methods,
2481 name,
2482 signature,
2483 OverpassLookupMode::find,
2484 StaticLookupMode::find,
2485 PrivateLookupMode::find);
2486 }
2487
2488 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2489 const Symbol* name,
2490 const Symbol* signature,
2491 OverpassLookupMode overpass_mode,
2492 StaticLookupMode static_mode,
2493 PrivateLookupMode private_mode) {
2494 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2495 return hit >= 0 ? methods->at(hit): nullptr;
2496 }
2497
2498 // true if method matches signature and conforms to skipping_X conditions.
2499 static bool method_matches(const Method* m,
2500 const Symbol* signature,
2501 bool skipping_overpass,
2502 bool skipping_static,
2503 bool skipping_private) {
2504 return ((m->signature() == signature) &&
2505 (!skipping_overpass || !m->is_overpass()) &&
2506 (!skipping_static || !m->is_static()) &&
2507 (!skipping_private || !m->is_private()));
2508 }
2509
2510 // Used directly for default_methods to find the index into the
2511 // default_vtable_indices, and indirectly by find_method
2512 // find_method_index looks in the local methods array to return the index
2513 // of the matching name/signature. If, overpass methods are being ignored,
2514 // the search continues to find a potential non-overpass match. This capability
2515 // is important during method resolution to prefer a static method, for example,
2516 // over an overpass method.
2517 // There is the possibility in any _method's array to have the same name/signature
2518 // for a static method, an overpass method and a local instance method
2519 // To correctly catch a given method, the search criteria may need
2520 // to explicitly skip the other two. For local instance methods, it
2521 // is often necessary to skip private methods
2522 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2523 const Symbol* name,
2524 const Symbol* signature,
2525 OverpassLookupMode overpass_mode,
2526 StaticLookupMode static_mode,
2527 PrivateLookupMode private_mode) {
2528 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2529 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2530 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2531 const int hit = quick_search(methods, name);
2532 if (hit != -1) {
2533 const Method* const m = methods->at(hit);
2534
2535 // Do linear search to find matching signature. First, quick check
2536 // for common case, ignoring overpasses if requested.
2537 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2538 return hit;
2539 }
2540
2541 // search downwards through overloaded methods
2542 int i;
2543 for (i = hit - 1; i >= 0; --i) {
2544 const Method* const m = methods->at(i);
2545 assert(m->is_method(), "must be method");
2546 if (m->name() != name) {
2547 break;
2548 }
2549 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2550 return i;
2551 }
2552 }
2553 // search upwards
2554 for (i = hit + 1; i < methods->length(); ++i) {
2555 const Method* const m = methods->at(i);
2556 assert(m->is_method(), "must be method");
2557 if (m->name() != name) {
2558 break;
2559 }
2560 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2561 return i;
2562 }
2563 }
2564 // not found
2565 #ifdef ASSERT
2566 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2567 linear_search(methods, name, signature);
2568 assert(-1 == index, "binary search should have found entry %d", index);
2569 #endif
2570 }
2571 return -1;
2572 }
2573
2574 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2575 return find_method_by_name(methods(), name, end);
2576 }
2577
2578 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2579 const Symbol* name,
2580 int* end_ptr) {
2581 assert(end_ptr != nullptr, "just checking");
2582 int start = quick_search(methods, name);
2583 int end = start + 1;
2584 if (start != -1) {
2585 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2586 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2587 *end_ptr = end;
2588 return start;
2589 }
2590 return -1;
2591 }
2592
2593 // uncached_lookup_method searches both the local class methods array and all
2594 // superclasses methods arrays, skipping any overpass methods in superclasses,
2595 // and possibly skipping private methods.
2596 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2597 const Symbol* signature,
2598 OverpassLookupMode overpass_mode,
2599 PrivateLookupMode private_mode) const {
2600 OverpassLookupMode overpass_local_mode = overpass_mode;
2601 const InstanceKlass* klass = this;
2602 while (klass != nullptr) {
2603 Method* const method = klass->find_method_impl(name,
2604 signature,
2605 overpass_local_mode,
2606 StaticLookupMode::find,
2607 private_mode);
2608 if (method != nullptr) {
2609 return method;
2610 }
2611 if (name == vmSymbols::object_initializer_name()) {
2612 break; // <init> is never inherited
2613 }
2614 klass = klass->super();
2615 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2616 }
2617 return nullptr;
2618 }
2619
2620 #ifdef ASSERT
2621 // search through class hierarchy and return true if this class or
2622 // one of the superclasses was redefined
2623 bool InstanceKlass::has_redefined_this_or_super() const {
2624 const InstanceKlass* klass = this;
2625 while (klass != nullptr) {
2626 if (klass->has_been_redefined()) {
2627 return true;
2628 }
2629 klass = klass->super();
2630 }
2631 return false;
2632 }
2633 #endif
2634
2635 // lookup a method in the default methods list then in all transitive interfaces
2636 // Do NOT return private or static methods
2637 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2638 Symbol* signature) const {
2639 Method* m = nullptr;
2640 if (default_methods() != nullptr) {
2641 m = find_method(default_methods(), name, signature);
2642 }
2643 // Look up interfaces
2644 if (m == nullptr) {
2645 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2646 }
2647 return m;
2648 }
2649
2650 // lookup a method in all the interfaces that this class implements
2651 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2652 // They should only be found in the initial InterfaceMethodRef
2653 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2654 Symbol* signature,
2655 DefaultsLookupMode defaults_mode) const {
2656 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2657 int num_ifs = all_ifs->length();
2658 InstanceKlass *ik = nullptr;
2659 for (int i = 0; i < num_ifs; i++) {
2660 ik = all_ifs->at(i);
2661 Method* m = ik->lookup_method(name, signature);
2662 if (m != nullptr && m->is_public() && !m->is_static() &&
2663 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2664 return m;
2665 }
2666 }
2667 return nullptr;
2668 }
2669
2670 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2671 :_st(st), _verbose(verbose) {
2672 ResourceMark rm;
2673 _st->print("%-18s ", "KlassAddr");
2674 _st->print("%-4s ", "Size");
2675 _st->print("%-20s ", "State");
2676 _st->print("%-7s ", "Flags");
2677 _st->print("%-5s ", "ClassName");
2678 _st->cr();
2679 }
2680
2681 void PrintClassClosure::do_klass(Klass* k) {
2682 ResourceMark rm;
2683 // klass pointer
2684 _st->print(PTR_FORMAT " ", p2i(k));
2685 // klass size
2686 _st->print("%4d ", k->size());
2687 // initialization state
2688 if (k->is_instance_klass()) {
2689 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2690 } else {
2691 _st->print("%-20s ","");
2692 }
2693 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2694 char buf[10];
2695 int i = 0;
2696 if (k->has_finalizer()) buf[i++] = 'F';
2697 if (k->is_instance_klass()) {
2698 InstanceKlass* ik = InstanceKlass::cast(k);
2699 if (ik->has_final_method()) buf[i++] = 'f';
2700 if (ik->is_rewritten()) buf[i++] = 'W';
2701 if (ik->is_contended()) buf[i++] = 'C';
2702 if (ik->has_been_redefined()) buf[i++] = 'R';
2703 if (ik->in_aot_cache()) buf[i++] = 'S';
2704 }
2705 buf[i++] = '\0';
2706 _st->print("%-7s ", buf);
2707 // klass name
2708 _st->print("%-5s ", k->external_name());
2709 // end
2710 _st->cr();
2711 if (_verbose) {
2712 k->print_on(_st);
2713 }
2714 }
2715
2716 /* jni_id_for for jfieldIds only */
2717 JNIid* InstanceKlass::jni_id_for(int offset) {
2718 MutexLocker ml(JfieldIdCreation_lock);
2719 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2720 if (probe == nullptr) {
2721 // Allocate new static field identifier
2722 probe = new JNIid(this, offset, jni_ids());
2723 set_jni_ids(probe);
2724 }
2725 return probe;
2726 }
2727
2728 u2 InstanceKlass::enclosing_method_data(int offset) const {
2729 const Array<jushort>* const inner_class_list = inner_classes();
2730 if (inner_class_list == nullptr) {
2731 return 0;
2732 }
2733 const int length = inner_class_list->length();
2734 if (length % inner_class_next_offset == 0) {
2735 return 0;
2736 }
2737 const int index = length - enclosing_method_attribute_size;
2738 assert(offset < enclosing_method_attribute_size, "invalid offset");
2739 return inner_class_list->at(index + offset);
2740 }
2741
2742 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2743 u2 method_index) {
2744 Array<jushort>* inner_class_list = inner_classes();
2745 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2746 int length = inner_class_list->length();
2747 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2748 int index = length - enclosing_method_attribute_size;
2749 inner_class_list->at_put(
2750 index + enclosing_method_class_index_offset, class_index);
2751 inner_class_list->at_put(
2752 index + enclosing_method_method_index_offset, method_index);
2753 }
2754 }
2755
2756 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2757 if (method->is_old() && !method->is_obsolete()) {
2758 // If the method passed in is old (but not obsolete), use the current version.
2759 method = method_with_idnum((int)idnum);
2760 assert(method != nullptr, "old and but not obsolete, so should exist");
2761 }
2762 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2763 AtomicAccess::release_store(&jmeths[idnum + 1], new_id);
2764 return new_id;
2765 }
2766
2767 // Allocate the jmethodID cache.
2768 static jmethodID* create_jmethod_id_cache(size_t size) {
2769 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2770 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2771 // cache size is stored in element[0], other elements offset by one
2772 jmeths[0] = (jmethodID)size;
2773 return jmeths;
2774 }
2775
2776 // When reading outside a lock, use this.
2777 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const {
2778 return AtomicAccess::load_acquire(&_methods_jmethod_ids);
2779 }
2780
2781 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) {
2782 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths);
2783 }
2784
2785 // Lookup or create a jmethodID.
2786 jmethodID InstanceKlass::get_jmethod_id(Method* method) {
2787 int idnum = method->method_idnum();
2788 jmethodID* jmeths = methods_jmethod_ids_acquire();
2789
2790 // We use a double-check locking idiom here because this cache is
2791 // performance sensitive. In the normal system, this cache only
2792 // transitions from null to non-null which is safe because we use
2793 // release_set_methods_jmethod_ids() to advertise the new cache.
2794 // A partially constructed cache should never be seen by a racing
2795 // thread. We also use release_store() to save a new jmethodID
2796 // in the cache so a partially constructed jmethodID should never be
2797 // seen either. Cache reads of existing jmethodIDs proceed without a
2798 // lock, but cache writes of a new jmethodID requires uniqueness and
2799 // creation of the cache itself requires no leaks so a lock is
2800 // acquired in those two cases.
2801 //
2802 // If the RedefineClasses() API has been used, then this cache grows
2803 // in the redefinition safepoint.
2804
2805 if (jmeths == nullptr) {
2806 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2807 jmeths = _methods_jmethod_ids;
2808 // Still null?
2809 if (jmeths == nullptr) {
2810 size_t size = idnum_allocated_count();
2811 assert(size > (size_t)idnum, "should already have space");
2812 jmeths = create_jmethod_id_cache(size);
2813 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2814
2815 // publish jmeths
2816 release_set_methods_jmethod_ids(jmeths);
2817 return new_id;
2818 }
2819 }
2820
2821 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2822 if (id == nullptr) {
2823 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2824 id = jmeths[idnum + 1];
2825 // Still null?
2826 if (id == nullptr) {
2827 return update_jmethod_id(jmeths, method, idnum);
2828 }
2829 }
2830 return id;
2831 }
2832
2833 void InstanceKlass::update_methods_jmethod_cache() {
2834 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2835 jmethodID* cache = _methods_jmethod_ids;
2836 if (cache != nullptr) {
2837 size_t size = idnum_allocated_count();
2838 size_t old_size = (size_t)cache[0];
2839 if (old_size < size + 1) {
2840 // Allocate a larger one and copy entries to the new one.
2841 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2842 jmethodID* new_cache = create_jmethod_id_cache(size);
2843
2844 for (int i = 1; i <= (int)old_size; i++) {
2845 new_cache[i] = cache[i];
2846 }
2847 _methods_jmethod_ids = new_cache;
2848 FREE_C_HEAP_ARRAY(jmethodID, cache);
2849 }
2850 }
2851 }
2852
2853 // Make a jmethodID for all methods in this class. This makes getting all method
2854 // ids much, much faster with classes with more than 8
2855 // methods, and has a *substantial* effect on performance with jvmti
2856 // code that loads all jmethodIDs for all classes.
2857 void InstanceKlass::make_methods_jmethod_ids() {
2858 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2859 jmethodID* jmeths = _methods_jmethod_ids;
2860 if (jmeths == nullptr) {
2861 jmeths = create_jmethod_id_cache(idnum_allocated_count());
2862 release_set_methods_jmethod_ids(jmeths);
2863 }
2864
2865 int length = methods()->length();
2866 for (int index = 0; index < length; index++) {
2867 Method* m = methods()->at(index);
2868 int idnum = m->method_idnum();
2869 assert(!m->is_old(), "should not have old methods or I'm confused");
2870 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]);
2871 if (!m->is_overpass() && // skip overpasses
2872 id == nullptr) {
2873 id = Method::make_jmethod_id(class_loader_data(), m);
2874 AtomicAccess::release_store(&jmeths[idnum + 1], id);
2875 }
2876 }
2877 }
2878
2879 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2880 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2881 int idnum = method->method_idnum();
2882 jmethodID* jmeths = methods_jmethod_ids_acquire();
2883 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2884 }
2885
2886 inline DependencyContext InstanceKlass::dependencies() {
2887 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2888 return dep_context;
2889 }
2890
2891 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2892 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2893 }
2894
2895 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2896 assert_lock_strong(CodeCache_lock);
2897 dependencies().add_dependent_nmethod(nm);
2898 }
2899
2900 void InstanceKlass::clean_dependency_context() {
2901 dependencies().clean_unloading_dependents();
2902 }
2903
2904 #ifndef PRODUCT
2905 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2906 dependencies().print_dependent_nmethods(verbose);
2907 }
2908
2909 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2910 return dependencies().is_dependent_nmethod(nm);
2911 }
2912 #endif //PRODUCT
2913
2914 void InstanceKlass::clean_weak_instanceklass_links() {
2915 clean_implementors_list();
2916 clean_method_data();
2917 }
2918
2919 void InstanceKlass::clean_implementors_list() {
2920 assert(is_loader_alive(), "this klass should be live");
2921 if (is_interface()) {
2922 assert (ClassUnloading, "only called for ClassUnloading");
2923 for (;;) {
2924 // Use load_acquire due to competing with inserts
2925 InstanceKlass* volatile* iklass = adr_implementor();
2926 assert(iklass != nullptr, "Klass must not be null");
2927 InstanceKlass* impl = AtomicAccess::load_acquire(iklass);
2928 if (impl != nullptr && !impl->is_loader_alive()) {
2929 // null this field, might be an unloaded instance klass or null
2930 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2931 // Successfully unlinking implementor.
2932 if (log_is_enabled(Trace, class, unload)) {
2933 ResourceMark rm;
2934 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2935 }
2936 return;
2937 }
2938 } else {
2939 return;
2940 }
2941 }
2942 }
2943 }
2944
2945 void InstanceKlass::clean_method_data() {
2946 for (int m = 0; m < methods()->length(); m++) {
2947 MethodData* mdo = methods()->at(m)->method_data();
2948 if (mdo != nullptr) {
2949 mdo->clean_method_data(/*always_clean*/false);
2950 }
2951 }
2952 }
2953
2954 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2955 Klass::metaspace_pointers_do(it);
2956
2957 if (log_is_enabled(Trace, aot)) {
2958 ResourceMark rm;
2959 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2960 }
2961
2962 it->push(&_annotations);
2963 it->push((Klass**)&_array_klasses);
2964 if (!is_rewritten()) {
2965 it->push(&_constants, MetaspaceClosure::_writable);
2966 } else {
2967 it->push(&_constants);
2968 }
2969 it->push(&_inner_classes);
2970 #if INCLUDE_JVMTI
2971 it->push(&_previous_versions);
2972 #endif
2973 #if INCLUDE_CDS
2974 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2975 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2976 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2977 // The length check on the _methods is necessary because classes which don't have any
2978 // methods share the Universe::_the_empty_method_array which is in the RO region.
2979 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2980 // To handle jsr bytecode, new Method* maybe stored into _methods
2981 it->push(&_methods, MetaspaceClosure::_writable);
2982 } else {
2983 #endif
2984 it->push(&_methods);
2985 #if INCLUDE_CDS
2986 }
2987 #endif
2988 it->push(&_default_methods);
2989 it->push(&_local_interfaces);
2990 it->push(&_transitive_interfaces);
2991 it->push(&_method_ordering);
2992 if (!is_rewritten()) {
2993 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2994 } else {
2995 it->push(&_default_vtable_indices);
2996 }
2997
2998 it->push(&_fieldinfo_stream);
2999 it->push(&_fieldinfo_search_table);
3000 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
3001 it->push(&_fields_status, MetaspaceClosure::_writable);
3002
3003 if (itable_length() > 0) {
3004 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
3005 int method_table_offset_in_words = ioe->offset()/wordSize;
3006 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
3007
3008 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
3009 / itableOffsetEntry::size();
3010
3011 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
3012 if (ioe->interface_klass() != nullptr) {
3013 it->push(ioe->interface_klass_addr());
3014 itableMethodEntry* ime = ioe->first_method_entry(this);
3015 int n = klassItable::method_count_for_interface(ioe->interface_klass());
3016 for (int index = 0; index < n; index ++) {
3017 it->push(ime[index].method_addr());
3018 }
3019 }
3020 }
3021 }
3022
3023 it->push(&_nest_host);
3024 it->push(&_nest_members);
3025 it->push(&_permitted_subclasses);
3026 it->push(&_loadable_descriptors);
3027 it->push(&_acmp_maps_array, MetaspaceClosure::_writable);
3028 it->push(&_record_components);
3029 it->push(&_inline_layout_info_array, MetaspaceClosure::_writable);
3030
3031 if (CDSConfig::is_dumping_full_module_graph() && !defined_by_other_loaders()) {
3032 it->push(&_package_entry);
3033 }
3034 }
3035
3036 #if INCLUDE_CDS
3037 void InstanceKlass::remove_unshareable_info() {
3038
3039 if (is_linked()) {
3040 assert(can_be_verified_at_dumptime(), "must be");
3041 // Remember this so we can avoid walking the hierarchy at runtime.
3042 set_verified_at_dump_time();
3043 }
3044
3045 _misc_flags.set_has_init_deps_processed(false);
3046
3047 Klass::remove_unshareable_info();
3048
3049 if (SystemDictionaryShared::has_class_failed_verification(this)) {
3050 // Classes are attempted to link during dumping and may fail,
3051 // but these classes are still in the dictionary and class list in CLD.
3052 // If the class has failed verification, there is nothing else to remove.
3053 return;
3054 }
3055
3056 // Reset to the 'allocated' state to prevent any premature accessing to
3057 // a shared class at runtime while the class is still being loaded and
3058 // restored. A class' init_state is set to 'loaded' at runtime when it's
3059 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
3060 _init_state = allocated;
3061
3062 { // Otherwise this needs to take out the Compile_lock.
3063 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3064 init_implementor();
3065 }
3066
3067 // Call remove_unshareable_info() on other objects that belong to this class, except
3068 // for constants()->remove_unshareable_info(), which is called in a separate pass in
3069 // ArchiveBuilder::make_klasses_shareable(),
3070
3071 for (int i = 0; i < methods()->length(); i++) {
3072 Method* m = methods()->at(i);
3073 m->remove_unshareable_info();
3074 }
3075
3076 // do array classes also.
3077 if (array_klasses() != nullptr) {
3078 array_klasses()->remove_unshareable_info();
3079 }
3080
3081 // These are not allocated from metaspace. They are safe to set to nullptr.
3082 _source_debug_extension = nullptr;
3083 _dep_context = nullptr;
3084 _osr_nmethods_head = nullptr;
3085 #if INCLUDE_JVMTI
3086 _breakpoints = nullptr;
3087 _previous_versions = nullptr;
3088 _cached_class_file = nullptr;
3089 _jvmti_cached_class_field_map = nullptr;
3090 #endif
3091
3092 _init_thread = nullptr;
3093 _methods_jmethod_ids = nullptr;
3094 _jni_ids = nullptr;
3095 _oop_map_cache = nullptr;
3096 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
3097 // keep _nest_host
3098 } else {
3099 // clear _nest_host to ensure re-load at runtime
3100 _nest_host = nullptr;
3101 }
3102 init_shared_package_entry();
3103 _dep_context_last_cleaned = 0;
3104 DEBUG_ONLY(_shared_class_load_count = 0);
3105
3106 remove_unshareable_flags();
3107
3108 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
3109 }
3110
3111 void InstanceKlass::remove_unshareable_flags() {
3112 // clear all the flags/stats that shouldn't be in the archived version
3113 assert(!is_scratch_class(), "must be");
3114 assert(!has_been_redefined(), "must be");
3115 #if INCLUDE_JVMTI
3116 set_is_being_redefined(false);
3117 #endif
3118 set_has_resolved_methods(false);
3119 }
3120
3121 void InstanceKlass::remove_java_mirror() {
3122 Klass::remove_java_mirror();
3123
3124 // do array classes also.
3125 if (array_klasses() != nullptr) {
3126 array_klasses()->remove_java_mirror();
3127 }
3128 }
3129
3130 void InstanceKlass::init_shared_package_entry() {
3131 assert(CDSConfig::is_dumping_archive(), "must be");
3132 if (!CDSConfig::is_dumping_full_module_graph() || defined_by_other_loaders()) {
3133 _package_entry = nullptr;
3134 }
3135 }
3136
3137 void InstanceKlass::compute_has_loops_flag_for_methods() {
3138 Array<Method*>* methods = this->methods();
3139 for (int index = 0; index < methods->length(); ++index) {
3140 Method* m = methods->at(index);
3141 if (!m->is_overpass()) { // work around JDK-8305771
3142 m->compute_has_loops_flag();
3143 }
3144 }
3145 }
3146
3147 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
3148 PackageEntry* pkg_entry, TRAPS) {
3149 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
3150 // before the InstanceKlass is added to the SystemDictionary. Make
3151 // sure the current state is <loaded.
3152 assert(!is_loaded(), "invalid init state");
3153 assert(!shared_loading_failed(), "Must not try to load failed class again");
3154 set_package(loader_data, pkg_entry, CHECK);
3155 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
3156
3157 if (is_inline_klass()) {
3158 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
3159 }
3160
3161 Array<Method*>* methods = this->methods();
3162 int num_methods = methods->length();
3163 for (int index = 0; index < num_methods; ++index) {
3164 methods->at(index)->restore_unshareable_info(CHECK);
3165 }
3166 #if INCLUDE_JVMTI
3167 if (JvmtiExport::has_redefined_a_class()) {
3168 // Reinitialize vtable because RedefineClasses may have changed some
3169 // entries in this vtable for super classes so the CDS vtable might
3170 // point to old or obsolete entries. RedefineClasses doesn't fix up
3171 // vtables in the shared system dictionary, only the main one.
3172 // It also redefines the itable too so fix that too.
3173 // First fix any default methods that point to a super class that may
3174 // have been redefined.
3175 bool trace_name_printed = false;
3176 adjust_default_methods(&trace_name_printed);
3177 if (verified_at_dump_time()) {
3178 // Initialize vtable and itable for classes which can be verified at dump time.
3179 // Unlinked classes such as old classes with major version < 50 cannot be verified
3180 // at dump time.
3181 vtable().initialize_vtable();
3182 itable().initialize_itable();
3183 }
3184 }
3185 #endif // INCLUDE_JVMTI
3186
3187 // restore constant pool resolved references
3188 constants()->restore_unshareable_info(CHECK);
3189
3190 // Restore acmp_maps java array from the version stored in metadata.
3191 // if it cannot be found in the archive
3192 if (Arguments::is_valhalla_enabled() && has_acmp_maps_offset() && java_mirror()->obj_field(_acmp_maps_offset) == nullptr) {
3193 int acmp_maps_size = _acmp_maps_array->length();
3194 typeArrayOop map = oopFactory::new_intArray(acmp_maps_size, CHECK);
3195 typeArrayHandle map_h(THREAD, map);
3196 for (int i = 0; i < acmp_maps_size; i++) {
3197 map_h->int_at_put(i, _acmp_maps_array->at(i));
3198 }
3199 java_mirror()->obj_field_put(_acmp_maps_offset, map_h());
3200 }
3201
3202 if (array_klasses() != nullptr) {
3203 // To get a consistent list of classes we need MultiArray_lock to ensure
3204 // array classes aren't observed while they are being restored.
3205 RecursiveLocker rl(MultiArray_lock, THREAD);
3206 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
3207 // Array classes have null protection domain.
3208 // --> see ArrayKlass::complete_create_array_klass()
3209 if (class_loader_data() == nullptr) {
3210 ResourceMark rm(THREAD);
3211 log_debug(cds)(" loader_data %s ", loader_data == nullptr ? "nullptr" : "non null");
3212 log_debug(cds)(" this %s array_klasses %s ", this->name()->as_C_string(), array_klasses()->name()->as_C_string());
3213 }
3214 assert(!array_klasses()->is_refined_objArray_klass(), "must be non-refined objarrayklass");
3215 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3216 }
3217
3218 // Initialize @ValueBased class annotation if not already set in the archived klass.
3219 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
3220 set_is_value_based();
3221 }
3222
3223 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
3224 }
3225
3226 bool InstanceKlass::can_be_verified_at_dumptime() const {
3227 if (CDSConfig::is_dumping_dynamic_archive() && AOTMetaspace::in_aot_cache(this)) {
3228 // This is a class that was dumped into the base archive, so we know
3229 // it was verified at dump time.
3230 return true;
3231 }
3232
3233 if (CDSConfig::is_preserving_verification_constraints()) {
3234 return true;
3235 }
3236
3237 if (CDSConfig::is_old_class_for_verifier(this)) {
3238 // The old verifier does not save verification constraints, so at run time
3239 // SystemDictionaryShared::check_verification_constraints() will not work for this class.
3240 return false;
3241 }
3242 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) {
3243 return false;
3244 }
3245 Array<InstanceKlass*>* interfaces = local_interfaces();
3246 int len = interfaces->length();
3247 for (int i = 0; i < len; i++) {
3248 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3249 return false;
3250 }
3251 }
3252 return true;
3253 }
3254
3255 #endif // INCLUDE_CDS
3256
3257 #if INCLUDE_JVMTI
3258 static void clear_all_breakpoints(Method* m) {
3259 m->clear_all_breakpoints();
3260 }
3261 #endif
3262
3263 void InstanceKlass::unload_class(InstanceKlass* ik) {
3264
3265 if (ik->is_scratch_class()) {
3266 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
3267 return;
3268 }
3269 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
3270
3271 // Release dependencies.
3272 ik->dependencies().remove_all_dependents();
3273
3274 // notify the debugger
3275 if (JvmtiExport::should_post_class_unload()) {
3276 JvmtiExport::post_class_unload(ik);
3277 }
3278
3279 // notify ClassLoadingService of class unload
3280 ClassLoadingService::notify_class_unloaded(ik);
3281
3282 SystemDictionaryShared::handle_class_unloading(ik);
3283
3284 if (log_is_enabled(Info, class, unload)) {
3285 ResourceMark rm;
3286 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3287 }
3288
3289 Events::log_class_unloading(Thread::current(), ik);
3290
3291 #if INCLUDE_JFR
3292 assert(ik != nullptr, "invariant");
3293 EventClassUnload event;
3294 event.set_unloadedClass(ik);
3295 event.set_definingClassLoader(ik->class_loader_data());
3296 event.commit();
3297 #endif
3298 }
3299
3300 static void method_release_C_heap_structures(Method* m) {
3301 m->release_C_heap_structures();
3302 }
3303
3304 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3305 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3306 // Clean up C heap
3307 Klass::release_C_heap_structures();
3308
3309 // Deallocate and call destructors for MDO mutexes
3310 if (release_sub_metadata) {
3311 methods_do(method_release_C_heap_structures);
3312 }
3313
3314 // Deallocate oop map cache
3315 if (_oop_map_cache != nullptr) {
3316 delete _oop_map_cache;
3317 _oop_map_cache = nullptr;
3318 }
3319
3320 // Deallocate JNI identifiers for jfieldIDs
3321 JNIid::deallocate(jni_ids());
3322 set_jni_ids(nullptr);
3323
3324 jmethodID* jmeths = _methods_jmethod_ids;
3325 if (jmeths != nullptr) {
3326 release_set_methods_jmethod_ids(nullptr);
3327 FreeHeap(jmeths);
3328 }
3329
3330 assert(_dep_context == nullptr,
3331 "dependencies should already be cleaned");
3332
3333 #if INCLUDE_JVMTI
3334 // Deallocate breakpoint records
3335 if (breakpoints() != nullptr) {
3336 methods_do(clear_all_breakpoints);
3337 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3338 }
3339
3340 // deallocate the cached class file
3341 if (_cached_class_file != nullptr) {
3342 os::free(_cached_class_file);
3343 _cached_class_file = nullptr;
3344 }
3345 #endif
3346
3347 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3348
3349 if (release_sub_metadata) {
3350 constants()->release_C_heap_structures();
3351 }
3352 }
3353
3354 // The constant pool is on stack if any of the methods are executing or
3355 // referenced by handles.
3356 bool InstanceKlass::on_stack() const {
3357 return _constants->on_stack();
3358 }
3359
3360 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3361 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3362 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3363
3364 // minor and major version numbers of class file
3365 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3366 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3367 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3368 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3369
3370 bool InstanceKlass::supports_inline_types() const {
3371 return major_version() >= Verifier::VALUE_TYPES_MAJOR_VERSION && minor_version() == Verifier::JAVA_PREVIEW_MINOR_VERSION;
3372 }
3373
3374 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
3375 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3376 if (ik->constants()->version() == version) {
3377 return ik;
3378 }
3379 }
3380 return nullptr;
3381 }
3382
3383 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3384 if (array == nullptr) {
3385 _source_debug_extension = nullptr;
3386 } else {
3387 // Adding one to the attribute length in order to store a null terminator
3388 // character could cause an overflow because the attribute length is
3389 // already coded with an u4 in the classfile, but in practice, it's
3390 // unlikely to happen.
3391 assert((length+1) > length, "Overflow checking");
3392 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3393 for (int i = 0; i < length; i++) {
3394 sde[i] = array[i];
3395 }
3396 sde[length] = '\0';
3397 _source_debug_extension = sde;
3398 }
3399 }
3400
3401 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3402 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3403 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3404
3405 const char* InstanceKlass::signature_name() const {
3406 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3407 }
3408
3409 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3410 // Get the internal name as a c string
3411 const char* src = (const char*) (name()->as_C_string());
3412 const int src_length = (int)strlen(src);
3413
3414 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3415
3416 // Add L or Q as type indicator
3417 int dest_index = 0;
3418 dest[dest_index++] = c;
3419
3420 // Add the actual class name
3421 for (int src_index = 0; src_index < src_length; ) {
3422 dest[dest_index++] = src[src_index++];
3423 }
3424
3425 if (is_hidden()) { // Replace the last '+' with a '.'.
3426 for (int index = (int)src_length; index > 0; index--) {
3427 if (dest[index] == '+') {
3428 dest[index] = JVM_SIGNATURE_DOT;
3429 break;
3430 }
3431 }
3432 }
3433
3434 // Add the semicolon and the null
3435 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3436 dest[dest_index] = '\0';
3437 return dest;
3438 }
3439
3440 ModuleEntry* InstanceKlass::module() const {
3441 if (is_hidden() &&
3442 in_unnamed_package() &&
3443 class_loader_data()->has_class_mirror_holder()) {
3444 // For a non-strong hidden class defined to an unnamed package,
3445 // its (class held) CLD will not have an unnamed module created for it.
3446 // Two choices to find the correct ModuleEntry:
3447 // 1. If hidden class is within a nest, use nest host's module
3448 // 2. Find the unnamed module off from the class loader
3449 // For now option #2 is used since a nest host is not set until
3450 // after the instance class is created in jvm_lookup_define_class().
3451 if (class_loader_data()->is_boot_class_loader_data()) {
3452 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3453 } else {
3454 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3455 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3456 return java_lang_Module::module_entry(module);
3457 }
3458 }
3459
3460 // Class is in a named package
3461 if (!in_unnamed_package()) {
3462 return _package_entry->module();
3463 }
3464
3465 // Class is in an unnamed package, return its loader's unnamed module
3466 return class_loader_data()->unnamed_module();
3467 }
3468
3469 bool InstanceKlass::in_javabase_module() const {
3470 return module()->name() == vmSymbols::java_base();
3471 }
3472
3473 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3474
3475 // ensure java/ packages only loaded by boot or platform builtin loaders
3476 // not needed for shared class since CDS does not archive prohibited classes.
3477 if (!in_aot_cache()) {
3478 check_prohibited_package(name(), loader_data, CHECK);
3479 }
3480
3481 if (in_aot_cache() && _package_entry != nullptr) {
3482 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3483 // we can use the saved package
3484 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be");
3485 return;
3486 } else {
3487 _package_entry = nullptr;
3488 }
3489 }
3490
3491 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3492 // it returns, so we need to decrement it when the current function exits.
3493 TempNewSymbol from_class_name =
3494 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3495
3496 Symbol* pkg_name;
3497 if (pkg_entry != nullptr) {
3498 pkg_name = pkg_entry->name();
3499 } else {
3500 pkg_name = from_class_name;
3501 }
3502
3503 if (pkg_name != nullptr && loader_data != nullptr) {
3504
3505 // Find in class loader's package entry table.
3506 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3507
3508 // If the package name is not found in the loader's package
3509 // entry table, it is an indication that the package has not
3510 // been defined. Consider it defined within the unnamed module.
3511 if (_package_entry == nullptr) {
3512
3513 if (!ModuleEntryTable::javabase_defined()) {
3514 // Before java.base is defined during bootstrapping, define all packages in
3515 // the java.base module. If a non-java.base package is erroneously placed
3516 // in the java.base module it will be caught later when java.base
3517 // is defined by ModuleEntryTable::verify_javabase_packages check.
3518 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3519 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3520 } else {
3521 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3522 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3523 }
3524
3525 // A package should have been successfully created
3526 DEBUG_ONLY(ResourceMark rm(THREAD));
3527 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3528 name()->as_C_string(), loader_data->loader_name_and_id());
3529 }
3530
3531 if (log_is_enabled(Debug, module)) {
3532 ResourceMark rm(THREAD);
3533 ModuleEntry* m = _package_entry->module();
3534 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3535 external_name(),
3536 pkg_name->as_C_string(),
3537 loader_data->loader_name_and_id(),
3538 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3539 }
3540 } else {
3541 ResourceMark rm(THREAD);
3542 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3543 external_name(),
3544 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3545 UNNAMED_MODULE);
3546 }
3547 }
3548
3549 // Function set_classpath_index ensures that for a non-null _package_entry
3550 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3551 // It then sets the classpath_index in the package entry record.
3552 //
3553 // The classpath_index field is used to find the entry on the boot loader class
3554 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3555 // in an unnamed module. It is also used to indicate (for all packages whose
3556 // classes are loaded by the boot loader) that at least one of the package's
3557 // classes has been loaded.
3558 void InstanceKlass::set_classpath_index(s2 path_index) {
3559 if (_package_entry != nullptr) {
3560 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3561 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3562 assert(path_index != -1, "Unexpected classpath_index");
3563 _package_entry->set_classpath_index(path_index);
3564 }
3565 }
3566
3567 // different versions of is_same_class_package
3568
3569 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3570 oop classloader1 = this->class_loader();
3571 PackageEntry* classpkg1 = this->package();
3572 if (class2->is_objArray_klass()) {
3573 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3574 }
3575
3576 oop classloader2;
3577 PackageEntry* classpkg2;
3578 if (class2->is_instance_klass()) {
3579 classloader2 = class2->class_loader();
3580 classpkg2 = class2->package();
3581 } else {
3582 assert(class2->is_typeArray_klass(), "should be type array");
3583 classloader2 = nullptr;
3584 classpkg2 = nullptr;
3585 }
3586
3587 // Same package is determined by comparing class loader
3588 // and package entries. Both must be the same. This rule
3589 // applies even to classes that are defined in the unnamed
3590 // package, they still must have the same class loader.
3591 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3592 return true;
3593 }
3594
3595 return false;
3596 }
3597
3598 // return true if this class and other_class are in the same package. Classloader
3599 // and classname information is enough to determine a class's package
3600 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3601 const Symbol* other_class_name) const {
3602 if (class_loader() != other_class_loader) {
3603 return false;
3604 }
3605 if (name()->fast_compare(other_class_name) == 0) {
3606 return true;
3607 }
3608
3609 {
3610 ResourceMark rm;
3611
3612 bool bad_class_name = false;
3613 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3614 if (bad_class_name) {
3615 return false;
3616 }
3617 // Check that package_from_class_name() returns null, not "", if there is no package.
3618 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3619
3620 const Symbol* const this_package_name =
3621 this->package() != nullptr ? this->package()->name() : nullptr;
3622
3623 if (this_package_name == nullptr || other_pkg == nullptr) {
3624 // One of the two doesn't have a package. Only return true if the other
3625 // one also doesn't have a package.
3626 return this_package_name == other_pkg;
3627 }
3628
3629 // Check if package is identical
3630 return this_package_name->fast_compare(other_pkg) == 0;
3631 }
3632 }
3633
3634 static bool is_prohibited_package_slow(Symbol* class_name) {
3635 // Caller has ResourceMark
3636 int length;
3637 jchar* unicode = class_name->as_unicode(length);
3638 return (length >= 5 &&
3639 unicode[0] == 'j' &&
3640 unicode[1] == 'a' &&
3641 unicode[2] == 'v' &&
3642 unicode[3] == 'a' &&
3643 unicode[4] == '/');
3644 }
3645
3646 // Only boot and platform class loaders can define classes in "java/" packages.
3647 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3648 ClassLoaderData* loader_data,
3649 TRAPS) {
3650 if (!loader_data->is_boot_class_loader_data() &&
3651 !loader_data->is_platform_class_loader_data() &&
3652 class_name != nullptr && class_name->utf8_length() >= 5) {
3653 ResourceMark rm(THREAD);
3654 bool prohibited;
3655 const u1* base = class_name->base();
3656 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3657 prohibited = is_prohibited_package_slow(class_name);
3658 } else {
3659 char* name = class_name->as_C_string();
3660 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3661 }
3662 if (prohibited) {
3663 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3664 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3665 char* name = pkg_name->as_C_string();
3666 const char* class_loader_name = loader_data->loader_name_and_id();
3667 StringUtils::replace_no_expand(name, "/", ".");
3668 const char* msg_text1 = "Class loader (instance of): ";
3669 const char* msg_text2 = " tried to load prohibited package name: ";
3670 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3671 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3672 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3673 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3674 }
3675 }
3676 return;
3677 }
3678
3679 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3680 constantPoolHandle i_cp(THREAD, constants());
3681 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3682 int ioff = iter.inner_class_info_index();
3683 if (ioff != 0) {
3684 // Check to see if the name matches the class we're looking for
3685 // before attempting to find the class.
3686 if (i_cp->klass_name_at_matches(this, ioff)) {
3687 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3688 if (this == inner_klass) {
3689 *ooff = iter.outer_class_info_index();
3690 *noff = iter.inner_name_index();
3691 return true;
3692 }
3693 }
3694 }
3695 }
3696 return false;
3697 }
3698
3699 void InstanceKlass::check_can_be_annotated_with_NullRestricted(InstanceKlass* type, Symbol* container_klass_name, TRAPS) {
3700 assert(type->is_instance_klass(), "Sanity check");
3701 if (type->is_identity_class()) {
3702 ResourceMark rm(THREAD);
3703 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3704 err_msg("Class %s expects class %s to be a value class, but it is an identity class",
3705 container_klass_name->as_C_string(),
3706 type->external_name()));
3707 }
3708
3709 if (type->is_abstract()) {
3710 ResourceMark rm(THREAD);
3711 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(),
3712 err_msg("Class %s expects class %s to be concrete value type, but it is an abstract class",
3713 container_klass_name->as_C_string(),
3714 type->external_name()));
3715 }
3716 }
3717
3718 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3719 InstanceKlass* outer_klass = nullptr;
3720 *inner_is_member = false;
3721 int ooff = 0, noff = 0;
3722 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3723 if (has_inner_classes_attr) {
3724 constantPoolHandle i_cp(THREAD, constants());
3725 if (ooff != 0) {
3726 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3727 if (!ok->is_instance_klass()) {
3728 // If the outer class is not an instance klass then it cannot have
3729 // declared any inner classes.
3730 ResourceMark rm(THREAD);
3731 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3732 Exceptions::fthrow(
3733 THREAD_AND_LOCATION,
3734 vmSymbols::java_lang_IncompatibleClassChangeError(),
3735 "%s and %s disagree on InnerClasses attribute",
3736 ok->external_name(),
3737 external_name());
3738 return nullptr;
3739 }
3740 outer_klass = InstanceKlass::cast(ok);
3741 *inner_is_member = true;
3742 }
3743 if (nullptr == outer_klass) {
3744 // It may be a local class; try for that.
3745 int encl_method_class_idx = enclosing_method_class_index();
3746 if (encl_method_class_idx != 0) {
3747 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3748 outer_klass = InstanceKlass::cast(ok);
3749 *inner_is_member = false;
3750 }
3751 }
3752 }
3753
3754 // If no inner class attribute found for this class.
3755 if (nullptr == outer_klass) return nullptr;
3756
3757 // Throws an exception if outer klass has not declared k as an inner klass
3758 // We need evidence that each klass knows about the other, or else
3759 // the system could allow a spoof of an inner class to gain access rights.
3760 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3761 return outer_klass;
3762 }
3763
3764 u2 InstanceKlass::compute_modifier_flags() const {
3765 u2 access = access_flags().as_unsigned_short();
3766
3767 // But check if it happens to be member class.
3768 InnerClassesIterator iter(this);
3769 for (; !iter.done(); iter.next()) {
3770 int ioff = iter.inner_class_info_index();
3771 // Inner class attribute can be zero, skip it.
3772 // Strange but true: JVM spec. allows null inner class refs.
3773 if (ioff == 0) continue;
3774
3775 // only look at classes that are already loaded
3776 // since we are looking for the flags for our self.
3777 Symbol* inner_name = constants()->klass_name_at(ioff);
3778 if (name() == inner_name) {
3779 // This is really a member class.
3780 access = iter.inner_access_flags();
3781 break;
3782 }
3783 }
3784 if (!Arguments::is_valhalla_enabled()) {
3785 // Remember to strip ACC_SUPER bit without Valhalla
3786 access &= (~JVM_ACC_SUPER);
3787 }
3788 return access;
3789 }
3790
3791 jint InstanceKlass::jvmti_class_status() const {
3792 jint result = 0;
3793
3794 if (is_linked()) {
3795 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3796 }
3797
3798 if (is_initialized()) {
3799 assert(is_linked(), "Class status is not consistent");
3800 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3801 }
3802 if (is_in_error_state()) {
3803 result |= JVMTI_CLASS_STATUS_ERROR;
3804 }
3805 return result;
3806 }
3807
3808 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3809 bool implements_interface; // initialized by method_at_itable_or_null
3810 Method* m = method_at_itable_or_null(holder, index,
3811 implements_interface); // out parameter
3812 if (m != nullptr) {
3813 assert(implements_interface, "sanity");
3814 return m;
3815 } else if (implements_interface) {
3816 // Throw AbstractMethodError since corresponding itable slot is empty.
3817 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3818 } else {
3819 // If the interface isn't implemented by the receiver class,
3820 // the VM should throw IncompatibleClassChangeError.
3821 ResourceMark rm(THREAD);
3822 stringStream ss;
3823 bool same_module = (module() == holder->module());
3824 ss.print("Receiver class %s does not implement "
3825 "the interface %s defining the method to be called "
3826 "(%s%s%s)",
3827 external_name(), holder->external_name(),
3828 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3829 (same_module) ? "" : "; ",
3830 (same_module) ? "" : holder->class_in_module_of_loader());
3831 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3832 }
3833 }
3834
3835 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3836 klassItable itable(this);
3837 for (int i = 0; i < itable.size_offset_table(); i++) {
3838 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3839 if (offset_entry->interface_klass() == holder) {
3840 implements_interface = true;
3841 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3842 Method* m = ime[index].method();
3843 return m;
3844 }
3845 }
3846 implements_interface = false;
3847 return nullptr; // offset entry not found
3848 }
3849
3850 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3851 assert(is_linked(), "required");
3852 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3853 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3854
3855 int vtable_index = Method::invalid_vtable_index;
3856 Symbol* name = intf_method->name();
3857 Symbol* signature = intf_method->signature();
3858
3859 // First check in default method array
3860 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3861 int index = find_method_index(default_methods(),
3862 name, signature,
3863 Klass::OverpassLookupMode::find,
3864 Klass::StaticLookupMode::find,
3865 Klass::PrivateLookupMode::find);
3866 if (index >= 0) {
3867 vtable_index = default_vtable_indices()->at(index);
3868 }
3869 }
3870 if (vtable_index == Method::invalid_vtable_index) {
3871 // get vtable_index for miranda methods
3872 klassVtable vt = vtable();
3873 vtable_index = vt.index_of_miranda(name, signature);
3874 }
3875 return vtable_index;
3876 }
3877
3878 #if INCLUDE_JVMTI
3879 // update default_methods for redefineclasses for methods that are
3880 // not yet in the vtable due to concurrent subclass define and superinterface
3881 // redefinition
3882 // Note: those in the vtable, should have been updated via adjust_method_entries
3883 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3884 // search the default_methods for uses of either obsolete or EMCP methods
3885 if (default_methods() != nullptr) {
3886 for (int index = 0; index < default_methods()->length(); index ++) {
3887 Method* old_method = default_methods()->at(index);
3888 if (old_method == nullptr || !old_method->is_old()) {
3889 continue; // skip uninteresting entries
3890 }
3891 assert(!old_method->is_deleted(), "default methods may not be deleted");
3892 Method* new_method = old_method->get_new_method();
3893 default_methods()->at_put(index, new_method);
3894
3895 if (log_is_enabled(Info, redefine, class, update)) {
3896 ResourceMark rm;
3897 if (!(*trace_name_printed)) {
3898 log_info(redefine, class, update)
3899 ("adjust: klassname=%s default methods from name=%s",
3900 external_name(), old_method->method_holder()->external_name());
3901 *trace_name_printed = true;
3902 }
3903 log_debug(redefine, class, update, vtables)
3904 ("default method update: %s(%s) ",
3905 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3906 }
3907 }
3908 }
3909 }
3910 #endif // INCLUDE_JVMTI
3911
3912 // On-stack replacement stuff
3913 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3914 assert_lock_strong(NMethodState_lock);
3915 #ifndef PRODUCT
3916 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3917 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3918 "redundant OSR recompilation detected. memory leak in CodeCache!");
3919 #endif
3920 // only one compilation can be active
3921 assert(n->is_osr_method(), "wrong kind of nmethod");
3922 n->set_osr_link(osr_nmethods_head());
3923 set_osr_nmethods_head(n);
3924 // Raise the highest osr level if necessary
3925 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3926
3927 // Get rid of the osr methods for the same bci that have lower levels.
3928 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3929 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3930 if (inv != nullptr && inv->is_in_use()) {
3931 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3932 }
3933 }
3934 }
3935
3936 // Remove osr nmethod from the list. Return true if found and removed.
3937 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3938 // This is a short non-blocking critical region, so the no safepoint check is ok.
3939 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3940 assert(n->is_osr_method(), "wrong kind of nmethod");
3941 nmethod* last = nullptr;
3942 nmethod* cur = osr_nmethods_head();
3943 int max_level = CompLevel_none; // Find the max comp level excluding n
3944 Method* m = n->method();
3945 // Search for match
3946 bool found = false;
3947 while(cur != nullptr && cur != n) {
3948 if (m == cur->method()) {
3949 // Find max level before n
3950 max_level = MAX2(max_level, cur->comp_level());
3951 }
3952 last = cur;
3953 cur = cur->osr_link();
3954 }
3955 nmethod* next = nullptr;
3956 if (cur == n) {
3957 found = true;
3958 next = cur->osr_link();
3959 if (last == nullptr) {
3960 // Remove first element
3961 set_osr_nmethods_head(next);
3962 } else {
3963 last->set_osr_link(next);
3964 }
3965 }
3966 n->set_osr_link(nullptr);
3967 cur = next;
3968 while (cur != nullptr) {
3969 // Find max level after n
3970 if (m == cur->method()) {
3971 max_level = MAX2(max_level, cur->comp_level());
3972 }
3973 cur = cur->osr_link();
3974 }
3975 m->set_highest_osr_comp_level(max_level);
3976 return found;
3977 }
3978
3979 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3980 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3981 nmethod* osr = osr_nmethods_head();
3982 int found = 0;
3983 while (osr != nullptr) {
3984 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3985 if (osr->method() == m) {
3986 deopt_scope->mark(osr);
3987 found++;
3988 }
3989 osr = osr->osr_link();
3990 }
3991 return found;
3992 }
3993
3994 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3995 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3996 nmethod* osr = osr_nmethods_head();
3997 nmethod* best = nullptr;
3998 while (osr != nullptr) {
3999 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
4000 // There can be a time when a c1 osr method exists but we are waiting
4001 // for a c2 version. When c2 completes its osr nmethod we will trash
4002 // the c1 version and only be able to find the c2 version. However
4003 // while we overflow in the c1 code at back branches we don't want to
4004 // try and switch to the same code as we are already running
4005
4006 if (osr->method() == m &&
4007 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
4008 if (match_level) {
4009 if (osr->comp_level() == comp_level) {
4010 // Found a match - return it.
4011 return osr;
4012 }
4013 } else {
4014 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
4015 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
4016 // Found the best possible - return it.
4017 return osr;
4018 }
4019 best = osr;
4020 }
4021 }
4022 }
4023 osr = osr->osr_link();
4024 }
4025
4026 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
4027 if (best != nullptr && best->comp_level() >= comp_level) {
4028 return best;
4029 }
4030 return nullptr;
4031 }
4032
4033 // -----------------------------------------------------------------------------------------------------
4034 // Printing
4035
4036 #define BULLET " - "
4037
4038 static const char* state_names[] = {
4039 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
4040 };
4041
4042 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
4043 ResourceMark rm;
4044 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
4045 for (int i = 0; i < len; i++) forward_refs[i] = 0;
4046 for (int i = 0; i < len; i++) {
4047 intptr_t e = start[i];
4048 st->print("%d : " INTPTR_FORMAT, i, e);
4049 if (forward_refs[i] != 0) {
4050 int from = forward_refs[i];
4051 int off = (int) start[from];
4052 st->print(" (offset %d <= [%d])", off, from);
4053 }
4054 if (MetaspaceObj::is_valid((Metadata*)e)) {
4055 st->print(" ");
4056 ((Metadata*)e)->print_value_on(st);
4057 } else if (self != nullptr && e > 0 && e < 0x10000) {
4058 address location = self + e;
4059 int index = (int)((intptr_t*)location - start);
4060 st->print(" (offset %d => [%d])", (int)e, index);
4061 if (index >= 0 && index < len)
4062 forward_refs[index] = i;
4063 }
4064 st->cr();
4065 }
4066 }
4067
4068 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
4069 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
4070 }
4071
4072 const char* InstanceKlass::init_state_name() const {
4073 return state_names[init_state()];
4074 }
4075
4076 void InstanceKlass::print_on(outputStream* st) const {
4077 assert(is_klass(), "must be klass");
4078 Klass::print_on(st);
4079
4080 st->print(BULLET"instance size: %d", size_helper()); st->cr();
4081 st->print(BULLET"klass size: %d", size()); st->cr();
4082 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
4083 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
4084 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
4085 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
4086 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
4087 st->print(BULLET"sub: ");
4088 Klass* sub = subklass();
4089 int n;
4090 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
4091 if (n < MaxSubklassPrintSize) {
4092 sub->print_value_on(st);
4093 st->print(" ");
4094 }
4095 }
4096 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
4097 st->cr();
4098
4099 if (is_interface()) {
4100 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
4101 if (nof_implementors() == 1) {
4102 st->print_cr(BULLET"implementor: ");
4103 st->print(" ");
4104 implementor()->print_value_on(st);
4105 st->cr();
4106 }
4107 }
4108
4109
4110 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
4111 st->print(BULLET"methods: ");
4112 print_array_on(st, methods(), [](outputStream* ost, Method* method) {
4113 method->print_value_on(ost);
4114 });
4115 st->print(BULLET"method ordering: ");
4116 print_array_on(st, method_ordering(), [](outputStream* ost, int i) {
4117 ost->print("%d", i);
4118 });
4119 if (default_methods() != nullptr) {
4120 st->print(BULLET"default_methods: ");
4121 print_array_on(st, default_methods(), [](outputStream* ost, Method* method) {
4122 method->print_value_on(ost);
4123 });
4124 }
4125 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
4126 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
4127 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
4128
4129 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
4130
4131 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
4132 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
4133
4134 if (secondary_supers() != nullptr) {
4135 if (Verbose) {
4136 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
4137 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
4138 for (int i = 0; i < _secondary_supers->length(); i++) {
4139 ResourceMark rm; // for external_name()
4140 Klass* secondary_super = _secondary_supers->at(i);
4141 st->print(BULLET"%2d:", i);
4142 if (is_hashed) {
4143 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
4144 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
4145 st->print(" dist:%02d:", distance);
4146 }
4147 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
4148 }
4149 }
4150 }
4151 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
4152
4153 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
4154 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
4155 if (source_debug_extension() != nullptr) {
4156 st->print(BULLET"source debug extension: ");
4157 st->print("%s", source_debug_extension());
4158 st->cr();
4159 }
4160 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
4161 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
4162 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
4163 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
4164 {
4165 bool have_pv = false;
4166 // previous versions are linked together through the InstanceKlass
4167 for (InstanceKlass* pv_node = previous_versions();
4168 pv_node != nullptr;
4169 pv_node = pv_node->previous_versions()) {
4170 if (!have_pv)
4171 st->print(BULLET"previous version: ");
4172 have_pv = true;
4173 pv_node->constants()->print_value_on(st);
4174 }
4175 if (have_pv) st->cr();
4176 }
4177
4178 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
4179 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
4180 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
4181 print_on_maybe_null(st, BULLET"record components: ", record_components());
4182 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
4183 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
4184 if (java_mirror() != nullptr) {
4185 st->print(BULLET"java mirror: ");
4186 java_mirror()->print_value_on(st);
4187 st->cr();
4188 } else {
4189 st->print_cr(BULLET"java mirror: null");
4190 }
4191 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
4192 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
4193 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
4194 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
4195
4196 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
4197 // There is no oop so static and nonstatic printing can use the same printer.
4198 FieldPrinter field_printer(st);
4199 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
4200 ik->do_local_static_fields(&field_printer);
4201 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
4202 ik->print_nonstatic_fields(&field_printer);
4203
4204 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
4205 OopMapBlock* map = start_of_nonstatic_oop_maps();
4206 OopMapBlock* end_map = map + nonstatic_oop_map_count();
4207 while (map < end_map) {
4208 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
4209 map++;
4210 }
4211 st->cr();
4212
4213 if (fieldinfo_search_table() != nullptr) {
4214 st->print_cr(BULLET"---- field info search table:");
4215 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
4216 }
4217 }
4218
4219 void InstanceKlass::print_value_on(outputStream* st) const {
4220 assert(is_klass(), "must be klass");
4221 if (Verbose || WizardMode) access_flags().print_on(st);
4222 name()->print_value_on(st);
4223 }
4224
4225 void FieldPrinter::do_field(fieldDescriptor* fd) {
4226 for (int i = 0; i < _indent; i++) _st->print(" ");
4227 _st->print(BULLET);
4228 // Handles the cases of static fields or instance fields but no oop is given.
4229 if (_obj == nullptr) {
4230 fd->print_on(_st, _base_offset);
4231 _st->cr();
4232 } else {
4233 fd->print_on_for(_st, _obj, _indent, _base_offset);
4234 if (!fd->field_flags().is_flat()) _st->cr();
4235 }
4236 }
4237
4238
4239 void InstanceKlass::oop_print_on(oop obj, outputStream* st, int indent, int base_offset) {
4240 Klass::oop_print_on(obj, st);
4241
4242 if (this == vmClasses::String_klass()) {
4243 typeArrayOop value = java_lang_String::value(obj);
4244 juint length = java_lang_String::length(obj);
4245 if (value != nullptr &&
4246 value->is_typeArray() &&
4247 length <= (juint) value->length()) {
4248 st->print(BULLET"string: ");
4249 java_lang_String::print(obj, st);
4250 st->cr();
4251 }
4252 }
4253
4254 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
4255 FieldPrinter print_field(st, obj, indent, base_offset);
4256 print_nonstatic_fields(&print_field);
4257
4258 if (this == vmClasses::Class_klass()) {
4259 st->print(BULLET"signature: ");
4260 java_lang_Class::print_signature(obj, st);
4261 st->cr();
4262 Klass* real_klass = java_lang_Class::as_Klass(obj);
4263 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4264 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4265 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4266 }
4267 } else if (this == vmClasses::MethodType_klass()) {
4268 st->print(BULLET"signature: ");
4269 java_lang_invoke_MethodType::print_signature(obj, st);
4270 st->cr();
4271 }
4272 }
4273
4274 #ifndef PRODUCT
4275
4276 bool InstanceKlass::verify_itable_index(int i) {
4277 int method_count = klassItable::method_count_for_interface(this);
4278 assert(i >= 0 && i < method_count, "index out of bounds");
4279 return true;
4280 }
4281
4282 #endif //PRODUCT
4283
4284 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4285 st->print("a ");
4286 name()->print_value_on(st);
4287 obj->print_address_on(st);
4288 if (this == vmClasses::String_klass()
4289 && java_lang_String::value(obj) != nullptr) {
4290 ResourceMark rm;
4291 int len = java_lang_String::length(obj);
4292 int plen = (len < 24 ? len : 12);
4293 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4294 st->print(" = \"%s\"", str);
4295 if (len > plen)
4296 st->print("...[%d]", len);
4297 } else if (this == vmClasses::Class_klass()) {
4298 Klass* k = java_lang_Class::as_Klass(obj);
4299 st->print(" = ");
4300 if (k != nullptr) {
4301 k->print_value_on(st);
4302 } else {
4303 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4304 st->print("%s", tname ? tname : "type?");
4305 }
4306 } else if (this == vmClasses::MethodType_klass()) {
4307 st->print(" = ");
4308 java_lang_invoke_MethodType::print_signature(obj, st);
4309 } else if (java_lang_boxing_object::is_instance(obj)) {
4310 st->print(" = ");
4311 java_lang_boxing_object::print(obj, st);
4312 } else if (this == vmClasses::LambdaForm_klass()) {
4313 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4314 if (vmentry != nullptr) {
4315 st->print(" => ");
4316 vmentry->print_value_on(st);
4317 }
4318 } else if (this == vmClasses::MemberName_klass()) {
4319 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4320 if (vmtarget != nullptr) {
4321 st->print(" = ");
4322 vmtarget->print_value_on(st);
4323 } else {
4324 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4325 oop name = java_lang_invoke_MemberName::name(obj);
4326 if (clazz != nullptr) {
4327 clazz->print_value_on(st);
4328 } else {
4329 st->print("null");
4330 }
4331 st->print(".");
4332 if (name != nullptr) {
4333 name->print_value_on(st);
4334 } else {
4335 st->print("null");
4336 }
4337 }
4338 }
4339 }
4340
4341 const char* InstanceKlass::internal_name() const {
4342 return external_name();
4343 }
4344
4345 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4346 const ModuleEntry* module_entry,
4347 const ClassFileStream* cfs) const {
4348
4349 if (ClassListWriter::is_enabled()) {
4350 ClassListWriter::write(this, cfs);
4351 }
4352
4353 print_class_load_helper(loader_data, module_entry, cfs);
4354 print_class_load_cause_logging();
4355 }
4356
4357 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4358 const ModuleEntry* module_entry,
4359 const ClassFileStream* cfs) const {
4360
4361 if (!log_is_enabled(Info, class, load)) {
4362 return;
4363 }
4364
4365 ResourceMark rm;
4366 LogMessage(class, load) msg;
4367 stringStream info_stream;
4368
4369 // Name and class hierarchy info
4370 info_stream.print("%s", external_name());
4371
4372 // Source
4373 if (cfs != nullptr) {
4374 if (cfs->source() != nullptr) {
4375 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4376 if (module_name != nullptr) {
4377 // When the boot loader created the stream, it didn't know the module name
4378 // yet. Let's format it now.
4379 if (cfs->from_boot_loader_modules_image()) {
4380 info_stream.print(" source: jrt:/%s", module_name);
4381 } else {
4382 info_stream.print(" source: %s", cfs->source());
4383 }
4384 } else {
4385 info_stream.print(" source: %s", cfs->source());
4386 }
4387 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4388 Thread* current = Thread::current();
4389 Klass* caller = current->is_Java_thread() ?
4390 JavaThread::cast(current)->security_get_caller_class(1):
4391 nullptr;
4392 // caller can be null, for example, during a JVMTI VM_Init hook
4393 if (caller != nullptr) {
4394 info_stream.print(" source: instance of %s", caller->external_name());
4395 } else {
4396 // source is unknown
4397 }
4398 } else {
4399 oop class_loader = loader_data->class_loader();
4400 info_stream.print(" source: %s", class_loader->klass()->external_name());
4401 }
4402 } else {
4403 assert(this->in_aot_cache(), "must be");
4404 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) {
4405 info_stream.print(" source: shared objects file (top)");
4406 } else {
4407 info_stream.print(" source: shared objects file");
4408 }
4409 }
4410
4411 msg.info("%s", info_stream.as_string());
4412
4413 if (log_is_enabled(Debug, class, load)) {
4414 stringStream debug_stream;
4415
4416 // Class hierarchy info
4417 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4418 p2i(this), p2i(super()));
4419
4420 // Interfaces
4421 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4422 debug_stream.print(" interfaces:");
4423 int length = local_interfaces()->length();
4424 for (int i = 0; i < length; i++) {
4425 debug_stream.print(" " PTR_FORMAT,
4426 p2i(local_interfaces()->at(i)));
4427 }
4428 }
4429
4430 // Class loader
4431 debug_stream.print(" loader: [");
4432 loader_data->print_value_on(&debug_stream);
4433 debug_stream.print("]");
4434
4435 // Classfile checksum
4436 if (cfs) {
4437 debug_stream.print(" bytes: %d checksum: %08x",
4438 cfs->length(),
4439 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4440 cfs->length()));
4441 }
4442
4443 msg.debug("%s", debug_stream.as_string());
4444 }
4445 }
4446
4447 void InstanceKlass::print_class_load_cause_logging() const {
4448 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4449 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4450 JavaThread* current = JavaThread::current();
4451 ResourceMark rm(current);
4452 const char* name = external_name();
4453
4454 if (LogClassLoadingCauseFor == nullptr ||
4455 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4456 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4457 return;
4458 }
4459
4460 // Log Java stack first
4461 {
4462 LogMessage(class, load, cause) msg;
4463 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4464
4465 info_stream.print_cr("Java stack when loading %s:", name);
4466 current->print_stack_on(&info_stream);
4467 }
4468
4469 // Log native stack second
4470 if (log_cause_native) {
4471 // Log to string first so that lines can be indented
4472 stringStream stack_stream;
4473 char buf[O_BUFLEN];
4474 address lastpc = nullptr;
4475 NativeStackPrinter nsp(current);
4476 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4477 true /* print_source_info */, -1 /* max stack */);
4478
4479 LogMessage(class, load, cause, native) msg;
4480 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4481 info_stream.print_cr("Native stack when loading %s:", name);
4482
4483 // Print each native stack line to the log
4484 int size = (int) stack_stream.size();
4485 char* stack = stack_stream.as_string();
4486 char* stack_end = stack + size;
4487 char* line_start = stack;
4488 for (char* p = stack; p < stack_end; p++) {
4489 if (*p == '\n') {
4490 *p = '\0';
4491 info_stream.print_cr("\t%s", line_start);
4492 line_start = p + 1;
4493 }
4494 }
4495 if (line_start < stack_end) {
4496 info_stream.print_cr("\t%s", line_start);
4497 }
4498 }
4499 }
4500 }
4501
4502 // Verification
4503
4504 class VerifyFieldClosure: public BasicOopIterateClosure {
4505 protected:
4506 template <class T> void do_oop_work(T* p) {
4507 oop obj = RawAccess<>::oop_load(p);
4508 if (!oopDesc::is_oop_or_null(obj)) {
4509 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4510 Universe::print_on(tty);
4511 guarantee(false, "boom");
4512 }
4513 }
4514 public:
4515 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4516 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4517 };
4518
4519 void InstanceKlass::verify_on(outputStream* st) {
4520 #ifndef PRODUCT
4521 // Avoid redundant verifies, this really should be in product.
4522 if (_verify_count == Universe::verify_count()) return;
4523 _verify_count = Universe::verify_count();
4524 #endif
4525
4526 // Verify Klass
4527 Klass::verify_on(st);
4528
4529 // Verify that klass is present in ClassLoaderData
4530 guarantee(class_loader_data()->contains_klass(this),
4531 "this class isn't found in class loader data");
4532
4533 // Verify vtables
4534 if (is_linked()) {
4535 // $$$ This used to be done only for m/s collections. Doing it
4536 // always seemed a valid generalization. (DLD -- 6/00)
4537 vtable().verify(st);
4538 }
4539
4540 // Verify first subklass
4541 if (subklass() != nullptr) {
4542 guarantee(subklass()->is_klass(), "should be klass");
4543 }
4544
4545 // Verify siblings
4546 Klass* super = this->super();
4547 Klass* sib = next_sibling();
4548 if (sib != nullptr) {
4549 if (sib == this) {
4550 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4551 }
4552
4553 guarantee(sib->is_klass(), "should be klass");
4554 guarantee(sib->super() == super, "siblings should have same superklass");
4555 }
4556
4557 // Verify local interfaces
4558 if (local_interfaces()) {
4559 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4560 for (int j = 0; j < local_interfaces->length(); j++) {
4561 InstanceKlass* e = local_interfaces->at(j);
4562 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4563 }
4564 }
4565
4566 // Verify transitive interfaces
4567 if (transitive_interfaces() != nullptr) {
4568 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4569 for (int j = 0; j < transitive_interfaces->length(); j++) {
4570 InstanceKlass* e = transitive_interfaces->at(j);
4571 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4572 }
4573 }
4574
4575 // Verify methods
4576 if (methods() != nullptr) {
4577 Array<Method*>* methods = this->methods();
4578 for (int j = 0; j < methods->length(); j++) {
4579 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4580 }
4581 for (int j = 0; j < methods->length() - 1; j++) {
4582 Method* m1 = methods->at(j);
4583 Method* m2 = methods->at(j + 1);
4584 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4585 }
4586 }
4587
4588 // Verify method ordering
4589 if (method_ordering() != nullptr) {
4590 Array<int>* method_ordering = this->method_ordering();
4591 int length = method_ordering->length();
4592 if (JvmtiExport::can_maintain_original_method_order() ||
4593 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4594 guarantee(length == methods()->length(), "invalid method ordering length");
4595 jlong sum = 0;
4596 for (int j = 0; j < length; j++) {
4597 int original_index = method_ordering->at(j);
4598 guarantee(original_index >= 0, "invalid method ordering index");
4599 guarantee(original_index < length, "invalid method ordering index");
4600 sum += original_index;
4601 }
4602 // Verify sum of indices 0,1,...,length-1
4603 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4604 } else {
4605 guarantee(length == 0, "invalid method ordering length");
4606 }
4607 }
4608
4609 // Verify default methods
4610 if (default_methods() != nullptr) {
4611 Array<Method*>* methods = this->default_methods();
4612 for (int j = 0; j < methods->length(); j++) {
4613 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4614 }
4615 for (int j = 0; j < methods->length() - 1; j++) {
4616 Method* m1 = methods->at(j);
4617 Method* m2 = methods->at(j + 1);
4618 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4619 }
4620 }
4621
4622 // Verify JNI static field identifiers
4623 if (jni_ids() != nullptr) {
4624 jni_ids()->verify(this);
4625 }
4626
4627 // Verify other fields
4628 if (constants() != nullptr) {
4629 guarantee(constants()->is_constantPool(), "should be constant pool");
4630 }
4631 }
4632
4633 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4634 Klass::oop_verify_on(obj, st);
4635 VerifyFieldClosure blk;
4636 obj->oop_iterate(&blk);
4637 }
4638
4639 // JNIid class for jfieldIDs only
4640 // Note to reviewers:
4641 // These JNI functions are just moved over to column 1 and not changed
4642 // in the compressed oops workspace.
4643 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) {
4644 _holder = holder;
4645 _offset = offset;
4646 _next = next;
4647 DEBUG_ONLY(_is_static_field_id = false;)
4648 }
4649
4650 JNIid* JNIid::find(int offset) {
4651 JNIid* current = this;
4652 while (current != nullptr) {
4653 if (current->offset() == offset) return current;
4654 current = current->next();
4655 }
4656 return nullptr;
4657 }
4658
4659 void JNIid::deallocate(JNIid* current) {
4660 while (current != nullptr) {
4661 JNIid* next = current->next();
4662 delete current;
4663 current = next;
4664 }
4665 }
4666
4667 void JNIid::verify(InstanceKlass* holder) {
4668 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4669 int end_field_offset;
4670 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize);
4671
4672 JNIid* current = this;
4673 while (current != nullptr) {
4674 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4675 #ifdef ASSERT
4676 int o = current->offset();
4677 if (current->is_static_field_id()) {
4678 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4679 }
4680 #endif
4681 current = current->next();
4682 }
4683 }
4684
4685 void InstanceKlass::set_init_state(ClassState state) {
4686 #ifdef ASSERT
4687 bool good_state = in_aot_cache() ? (_init_state <= state)
4688 : (_init_state < state);
4689 assert(good_state || state == allocated, "illegal state transition");
4690 #endif
4691 assert(_init_thread == nullptr, "should be cleared before state change");
4692 AtomicAccess::release_store(&_init_state, state);
4693 }
4694
4695 #if INCLUDE_JVMTI
4696
4697 // RedefineClasses() support for previous versions
4698
4699 // Globally, there is at least one previous version of a class to walk
4700 // during class unloading, which is saved because old methods in the class
4701 // are still running. Otherwise the previous version list is cleaned up.
4702 bool InstanceKlass::_should_clean_previous_versions = false;
4703
4704 // Returns true if there are previous versions of a class for class
4705 // unloading only. Also resets the flag to false. purge_previous_version
4706 // will set the flag to true if there are any left, i.e., if there's any
4707 // work to do for next time. This is to avoid the expensive code cache
4708 // walk in CLDG::clean_deallocate_lists().
4709 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4710 bool ret = _should_clean_previous_versions;
4711 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4712 ret ? "true" : "false");
4713 _should_clean_previous_versions = false;
4714 return ret;
4715 }
4716
4717 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'.
4718 // These obsolete methods only exist in the previous version and we're about to delete the memory for them.
4719 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table.
4720 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) {
4721 Array<Method*>* method_refs = klass->methods();
4722 for (int k = 0; k < method_refs->length(); k++) {
4723 Method* method = method_refs->at(k);
4724 // Only need to clear obsolete methods.
4725 if (method != nullptr && method->is_obsolete()) {
4726 method->clear_jmethod_id();
4727 }
4728 }
4729 }
4730
4731 // Purge previous versions before adding new previous versions of the class and
4732 // during class unloading.
4733 void InstanceKlass::purge_previous_version_list() {
4734 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4735 assert(has_been_redefined(), "Should only be called for main class");
4736
4737 // Quick exit.
4738 if (previous_versions() == nullptr) {
4739 return;
4740 }
4741
4742 // This klass has previous versions so see what we can cleanup
4743 // while it is safe to do so.
4744
4745 int deleted_count = 0; // leave debugging breadcrumbs
4746 int live_count = 0;
4747 ClassLoaderData* loader_data = class_loader_data();
4748 assert(loader_data != nullptr, "should never be null");
4749
4750 ResourceMark rm;
4751 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4752
4753 // previous versions are linked together through the InstanceKlass
4754 InstanceKlass* pv_node = previous_versions();
4755 InstanceKlass* last = this;
4756 int version = 0;
4757
4758 // check the previous versions list
4759 for (; pv_node != nullptr; ) {
4760
4761 ConstantPool* pvcp = pv_node->constants();
4762 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4763
4764 if (!pvcp->on_stack()) {
4765 // If the constant pool isn't on stack, none of the methods
4766 // are executing. Unlink this previous_version.
4767 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4768 // so will be deallocated during the next phase of class unloading.
4769 log_trace(redefine, class, iklass, purge)
4770 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4771 // Unlink from previous version list.
4772 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4773 InstanceKlass* next = pv_node->previous_versions();
4774 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4775 pv_node->link_previous_versions(nullptr); // point next to null
4776 last->link_previous_versions(next);
4777 // Delete this node directly. Nothing is referring to it and we don't
4778 // want it to increase the counter for metadata to delete in CLDG.
4779 MetadataFactory::free_metadata(loader_data, pv_node);
4780 pv_node = next;
4781 deleted_count++;
4782 version++;
4783 continue;
4784 } else {
4785 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4786 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4787 live_count++;
4788 if (pvcp->in_aot_cache()) {
4789 // Shared previous versions can never be removed so no cleaning is needed.
4790 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4791 } else {
4792 // Previous version alive, set that clean is needed for next time.
4793 _should_clean_previous_versions = true;
4794 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4795 }
4796 }
4797
4798 // next previous version
4799 last = pv_node;
4800 pv_node = pv_node->previous_versions();
4801 version++;
4802 }
4803 log_trace(redefine, class, iklass, purge)
4804 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4805 }
4806
4807 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4808 int emcp_method_count) {
4809 int obsolete_method_count = old_methods->length() - emcp_method_count;
4810
4811 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4812 _previous_versions != nullptr) {
4813 // We have a mix of obsolete and EMCP methods so we have to
4814 // clear out any matching EMCP method entries the hard way.
4815 int local_count = 0;
4816 for (int i = 0; i < old_methods->length(); i++) {
4817 Method* old_method = old_methods->at(i);
4818 if (old_method->is_obsolete()) {
4819 // only obsolete methods are interesting
4820 Symbol* m_name = old_method->name();
4821 Symbol* m_signature = old_method->signature();
4822
4823 // previous versions are linked together through the InstanceKlass
4824 int j = 0;
4825 for (InstanceKlass* prev_version = _previous_versions;
4826 prev_version != nullptr;
4827 prev_version = prev_version->previous_versions(), j++) {
4828
4829 Array<Method*>* method_refs = prev_version->methods();
4830 for (int k = 0; k < method_refs->length(); k++) {
4831 Method* method = method_refs->at(k);
4832
4833 if (!method->is_obsolete() &&
4834 method->name() == m_name &&
4835 method->signature() == m_signature) {
4836 // The current RedefineClasses() call has made all EMCP
4837 // versions of this method obsolete so mark it as obsolete
4838 log_trace(redefine, class, iklass, add)
4839 ("%s(%s): flush obsolete method @%d in version @%d",
4840 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4841
4842 method->set_is_obsolete();
4843 break;
4844 }
4845 }
4846
4847 // The previous loop may not find a matching EMCP method, but
4848 // that doesn't mean that we can optimize and not go any
4849 // further back in the PreviousVersion generations. The EMCP
4850 // method for this generation could have already been made obsolete,
4851 // but there still may be an older EMCP method that has not
4852 // been made obsolete.
4853 }
4854
4855 if (++local_count >= obsolete_method_count) {
4856 // no more obsolete methods so bail out now
4857 break;
4858 }
4859 }
4860 }
4861 }
4862 }
4863
4864 // Save the scratch_class as the previous version if any of the methods are running.
4865 // The previous_versions are used to set breakpoints in EMCP methods and they are
4866 // also used to clean MethodData links to redefined methods that are no longer running.
4867 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4868 int emcp_method_count) {
4869 assert(Thread::current()->is_VM_thread(),
4870 "only VMThread can add previous versions");
4871
4872 ResourceMark rm;
4873 log_trace(redefine, class, iklass, add)
4874 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4875
4876 // Clean out old previous versions for this class
4877 purge_previous_version_list();
4878
4879 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4880 // a previous redefinition may be made obsolete by this redefinition.
4881 Array<Method*>* old_methods = scratch_class->methods();
4882 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4883
4884 // If the constant pool for this previous version of the class
4885 // is not marked as being on the stack, then none of the methods
4886 // in this previous version of the class are on the stack so
4887 // we don't need to add this as a previous version.
4888 ConstantPool* cp_ref = scratch_class->constants();
4889 if (!cp_ref->on_stack()) {
4890 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4891 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4892 return;
4893 }
4894
4895 // Add previous version if any methods are still running or if this is
4896 // a shared class which should never be removed.
4897 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4898 scratch_class->link_previous_versions(previous_versions());
4899 link_previous_versions(scratch_class);
4900 if (cp_ref->in_aot_cache()) {
4901 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4902 } else {
4903 // We only set clean_previous_versions flag for processing during class
4904 // unloading for non-shared classes.
4905 _should_clean_previous_versions = true;
4906 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4907 }
4908 } // end add_previous_version()
4909
4910 #endif // INCLUDE_JVMTI
4911
4912 Method* InstanceKlass::method_with_idnum(int idnum) const {
4913 Method* m = nullptr;
4914 if (idnum < methods()->length()) {
4915 m = methods()->at(idnum);
4916 }
4917 if (m == nullptr || m->method_idnum() != idnum) {
4918 for (int index = 0; index < methods()->length(); ++index) {
4919 m = methods()->at(index);
4920 if (m->method_idnum() == idnum) {
4921 return m;
4922 }
4923 }
4924 // None found, return null for the caller to handle.
4925 return nullptr;
4926 }
4927 return m;
4928 }
4929
4930
4931 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4932 if (idnum >= methods()->length()) {
4933 return nullptr;
4934 }
4935 Method* m = methods()->at(idnum);
4936 if (m != nullptr && m->orig_method_idnum() == idnum) {
4937 return m;
4938 }
4939 // Obsolete method idnum does not match the original idnum
4940 for (int index = 0; index < methods()->length(); ++index) {
4941 m = methods()->at(index);
4942 if (m->orig_method_idnum() == idnum) {
4943 return m;
4944 }
4945 }
4946 // None found, return null for the caller to handle.
4947 return nullptr;
4948 }
4949
4950
4951 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4952 const InstanceKlass* holder = get_klass_version(version);
4953 if (holder == nullptr) {
4954 return nullptr; // The version of klass is gone, no method is found
4955 }
4956 return holder->method_with_orig_idnum(idnum);
4957 }
4958
4959 #if INCLUDE_JVMTI
4960 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4961 return _cached_class_file;
4962 }
4963
4964 jint InstanceKlass::get_cached_class_file_len() {
4965 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4966 }
4967
4968 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4969 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4970 }
4971 #endif
4972
4973 // Make a step iterating over the class hierarchy under the root class.
4974 // Skips subclasses if requested.
4975 void ClassHierarchyIterator::next() {
4976 assert(_current != nullptr, "required");
4977 if (_visit_subclasses && _current->subklass() != nullptr) {
4978 _current = _current->subklass();
4979 return; // visit next subclass
4980 }
4981 _visit_subclasses = true; // reset
4982 while (_current->next_sibling() == nullptr && _current != _root) {
4983 _current = _current->java_super(); // backtrack; no more sibling subclasses left
4984 }
4985 if (_current == _root) {
4986 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4987 _current = nullptr;
4988 return;
4989 }
4990 _current = _current->next_sibling();
4991 return; // visit next sibling subclass
4992 }