1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotClassInitializer.hpp"
26 #include "cds/archiveUtils.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/cdsEnumKlass.hpp"
29 #include "cds/classListWriter.hpp"
30 #include "cds/heapShared.hpp"
31 #include "cds/metaspaceShared.hpp"
32 #include "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeStream.hpp"
49 #include "interpreter/oopMapCache.hpp"
50 #include "interpreter/rewriter.hpp"
51 #include "jvm.h"
52 #include "jvmtifiles/jvmti.h"
53 #include "logging/log.hpp"
54 #include "klass.inline.hpp"
55 #include "logging/logMessage.hpp"
56 #include "logging/logStream.hpp"
57 #include "memory/allocation.inline.hpp"
58 #include "memory/iterator.inline.hpp"
59 #include "memory/metadataFactory.hpp"
60 #include "memory/metaspaceClosure.hpp"
61 #include "memory/oopFactory.hpp"
62 #include "memory/resourceArea.hpp"
63 #include "memory/universe.hpp"
64 #include "oops/fieldStreams.inline.hpp"
65 #include "oops/constantPool.hpp"
66 #include "oops/instanceClassLoaderKlass.hpp"
67 #include "oops/instanceKlass.inline.hpp"
68 #include "oops/instanceMirrorKlass.hpp"
69 #include "oops/instanceOop.hpp"
70 #include "oops/instanceStackChunkKlass.hpp"
71 #include "oops/klass.inline.hpp"
72 #include "oops/method.hpp"
73 #include "oops/oop.inline.hpp"
74 #include "oops/recordComponent.hpp"
75 #include "oops/symbol.hpp"
76 #include "prims/jvmtiExport.hpp"
77 #include "prims/jvmtiRedefineClasses.hpp"
78 #include "prims/jvmtiThreadState.hpp"
79 #include "prims/methodComparator.hpp"
80 #include "runtime/arguments.hpp"
81 #include "runtime/deoptimization.hpp"
82 #include "runtime/atomic.hpp"
83 #include "runtime/fieldDescriptor.inline.hpp"
84 #include "runtime/handles.inline.hpp"
85 #include "runtime/javaCalls.hpp"
86 #include "runtime/javaThread.inline.hpp"
87 #include "runtime/mutexLocker.hpp"
88 #include "runtime/orderAccess.hpp"
89 #include "runtime/os.inline.hpp"
90 #include "runtime/reflection.hpp"
91 #include "runtime/synchronizer.hpp"
92 #include "runtime/threads.hpp"
93 #include "services/classLoadingService.hpp"
94 #include "services/finalizerService.hpp"
95 #include "services/threadService.hpp"
96 #include "utilities/dtrace.hpp"
97 #include "utilities/events.hpp"
98 #include "utilities/macros.hpp"
99 #include "utilities/nativeStackPrinter.hpp"
100 #include "utilities/stringUtils.hpp"
101 #ifdef COMPILER1
102 #include "c1/c1_Compiler.hpp"
103 #endif
104 #if INCLUDE_JFR
105 #include "jfr/jfrEvents.hpp"
106 #endif
107
108 #ifdef DTRACE_ENABLED
109
110
111 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
112 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
113 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
114 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
115 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
116 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
117 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
118 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
119 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
120 { \
121 char* data = nullptr; \
122 int len = 0; \
123 Symbol* clss_name = name(); \
124 if (clss_name != nullptr) { \
125 data = (char*)clss_name->bytes(); \
126 len = clss_name->utf8_length(); \
127 } \
128 HOTSPOT_CLASS_INITIALIZATION_##type( \
129 data, len, (void*)class_loader(), thread_type); \
130 }
131
132 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
133 { \
134 char* data = nullptr; \
135 int len = 0; \
136 Symbol* clss_name = name(); \
137 if (clss_name != nullptr) { \
138 data = (char*)clss_name->bytes(); \
139 len = clss_name->utf8_length(); \
140 } \
141 HOTSPOT_CLASS_INITIALIZATION_##type( \
142 data, len, (void*)class_loader(), thread_type, wait); \
143 }
144
145 #else // ndef DTRACE_ENABLED
146
147 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
148 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
149
150 #endif // ndef DTRACE_ENABLED
151
152 bool InstanceKlass::_finalization_enabled = true;
153
154 static inline bool is_class_loader(const Symbol* class_name,
155 const ClassFileParser& parser) {
156 assert(class_name != nullptr, "invariant");
157
158 if (class_name == vmSymbols::java_lang_ClassLoader()) {
159 return true;
160 }
161
162 if (vmClasses::ClassLoader_klass_loaded()) {
163 const Klass* const super_klass = parser.super_klass();
164 if (super_klass != nullptr) {
165 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
166 return true;
167 }
168 }
169 }
170 return false;
171 }
172
173 static inline bool is_stack_chunk_class(const Symbol* class_name,
174 const ClassLoaderData* loader_data) {
175 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
176 loader_data->is_the_null_class_loader_data());
177 }
178
179 // private: called to verify that k is a static member of this nest.
180 // We know that k is an instance class in the same package and hence the
181 // same classloader.
182 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
183 assert(!is_hidden(), "unexpected hidden class");
184 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
185 if (log_is_enabled(Trace, class, nestmates)) {
186 ResourceMark rm(current);
187 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
188 k->external_name(), this->external_name());
189 }
190 return false;
191 }
192
193 if (log_is_enabled(Trace, class, nestmates)) {
194 ResourceMark rm(current);
195 log_trace(class, nestmates)("Checking nest membership of %s in %s",
196 k->external_name(), this->external_name());
197 }
198
199 // Check for the named class in _nest_members.
200 // We don't resolve, or load, any classes.
201 for (int i = 0; i < _nest_members->length(); i++) {
202 int cp_index = _nest_members->at(i);
203 Symbol* name = _constants->klass_name_at(cp_index);
204 if (name == k->name()) {
205 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
206 return true;
207 }
208 }
209 log_trace(class, nestmates)("- class is NOT a nest member!");
210 return false;
211 }
212
213 // Called to verify that k is a permitted subclass of this class.
214 // The incoming stringStream is used to format the messages for error logging and for the caller
215 // to use for exception throwing.
216 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
217 Thread* current = Thread::current();
218 assert(k != nullptr, "sanity check");
219 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
220 "unexpected empty _permitted_subclasses array");
221
222 if (log_is_enabled(Trace, class, sealed)) {
223 ResourceMark rm(current);
224 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
225 k->external_name(), this->external_name());
226 }
227
228 // Check that the class and its super are in the same module.
229 if (k->module() != this->module()) {
230 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
231 "and sealed class %s is in module '%s' with loader %s",
232 k->external_name(),
233 k->module()->name_as_C_string(),
234 k->module()->loader_data()->loader_name_and_id(),
235 this->external_name(),
236 this->module()->name_as_C_string(),
237 this->module()->loader_data()->loader_name_and_id());
238 log_trace(class, sealed)(" - %s", ss.as_string());
239 return false;
240 }
241
242 if (!k->is_public() && !is_same_class_package(k)) {
243 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
244 "and sealed class %s is in package '%s' with classloader %s",
245 k->external_name(),
246 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
247 k->module()->loader_data()->loader_name_and_id(),
248 this->external_name(),
249 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
250 this->module()->loader_data()->loader_name_and_id());
251 log_trace(class, sealed)(" - %s", ss.as_string());
252 return false;
253 }
254
255 for (int i = 0; i < _permitted_subclasses->length(); i++) {
256 int cp_index = _permitted_subclasses->at(i);
257 Symbol* name = _constants->klass_name_at(cp_index);
258 if (name == k->name()) {
259 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
260 return true;
261 }
262 }
263
264 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
265 k->external_name(), this->external_name());
266 log_trace(class, sealed)(" - %s", ss.as_string());
267 return false;
268 }
269
270 // Return nest-host class, resolving, validating and saving it if needed.
271 // In cases where this is called from a thread that cannot do classloading
272 // (such as a native JIT thread) then we simply return null, which in turn
273 // causes the access check to return false. Such code will retry the access
274 // from a more suitable environment later. Otherwise the _nest_host is always
275 // set once this method returns.
276 // Any errors from nest-host resolution must be preserved so they can be queried
277 // from higher-level access checking code, and reported as part of access checking
278 // exceptions.
279 // VirtualMachineErrors are propagated with a null return.
280 // Under any conditions where the _nest_host can be set to non-null the resulting
281 // value of it and, if applicable, the nest host resolution/validation error,
282 // are idempotent.
283 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
284 InstanceKlass* nest_host_k = _nest_host;
285 if (nest_host_k != nullptr) {
286 return nest_host_k;
287 }
288
289 ResourceMark rm(THREAD);
290
291 // need to resolve and save our nest-host class.
292 if (_nest_host_index != 0) { // we have a real nest_host
293 // Before trying to resolve check if we're in a suitable context
294 bool can_resolve = THREAD->can_call_java();
295 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
296 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
297 this->external_name());
298 return nullptr; // sentinel to say "try again from a different context"
299 }
300
301 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
302 this->external_name(),
303 _constants->klass_name_at(_nest_host_index)->as_C_string());
304
305 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
306 if (HAS_PENDING_EXCEPTION) {
307 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
308 return nullptr; // propagate VMEs
309 }
310 stringStream ss;
311 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
312 ss.print("Nest host resolution of %s with host %s failed: ",
313 this->external_name(), target_host_class);
314 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
315 const char* msg = ss.as_string(true /* on C-heap */);
316 constantPoolHandle cph(THREAD, constants());
317 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
318 CLEAR_PENDING_EXCEPTION;
319
320 log_trace(class, nestmates)("%s", msg);
321 } else {
322 // A valid nest-host is an instance class in the current package that lists this
323 // class as a nest member. If any of these conditions are not met the class is
324 // its own nest-host.
325 const char* error = nullptr;
326
327 // JVMS 5.4.4 indicates package check comes first
328 if (is_same_class_package(k)) {
329 // Now check actual membership. We can't be a member if our "host" is
330 // not an instance class.
331 if (k->is_instance_klass()) {
332 nest_host_k = InstanceKlass::cast(k);
333 bool is_member = nest_host_k->has_nest_member(THREAD, this);
334 if (is_member) {
335 _nest_host = nest_host_k; // save resolved nest-host value
336
337 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
338 this->external_name(), k->external_name());
339 return nest_host_k;
340 } else {
341 error = "current type is not listed as a nest member";
342 }
343 } else {
344 error = "host is not an instance class";
345 }
346 } else {
347 error = "types are in different packages";
348 }
349
350 // something went wrong, so record what and log it
351 {
352 stringStream ss;
353 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
354 this->external_name(),
355 this->class_loader_data()->loader_name_and_id(),
356 k->external_name(),
357 k->class_loader_data()->loader_name_and_id(),
358 error);
359 const char* msg = ss.as_string(true /* on C-heap */);
360 constantPoolHandle cph(THREAD, constants());
361 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
362 log_trace(class, nestmates)("%s", msg);
363 }
364 }
365 } else {
366 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
367 this->external_name());
368 }
369
370 // Either not in an explicit nest, or else an error occurred, so
371 // the nest-host is set to `this`. Any thread that sees this assignment
372 // will also see any setting of nest_host_error(), if applicable.
373 return (_nest_host = this);
374 }
375
376 // Dynamic nest member support: set this class's nest host to the given class.
377 // This occurs as part of the class definition, as soon as the instanceKlass
378 // has been created and doesn't require further resolution. The code:
379 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
380 // results in:
381 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
382 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
383 // We also know the "host" is a valid nest-host in the same package so we can
384 // assert some of those facts.
385 void InstanceKlass::set_nest_host(InstanceKlass* host) {
386 assert(is_hidden(), "must be a hidden class");
387 assert(host != nullptr, "null nest host specified");
388 assert(_nest_host == nullptr, "current class has resolved nest-host");
389 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
390 nest_host_error());
391 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
392 (host->_nest_host == host), "proposed host is not a valid nest-host");
393 // Can't assert this as package is not set yet:
394 // assert(is_same_class_package(host), "proposed host is in wrong package");
395
396 if (log_is_enabled(Trace, class, nestmates)) {
397 ResourceMark rm;
398 const char* msg = "";
399 // a hidden class does not expect a statically defined nest-host
400 if (_nest_host_index > 0) {
401 msg = "(the NestHost attribute in the current class is ignored)";
402 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
403 msg = "(the NestMembers attribute in the current class is ignored)";
404 }
405 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
406 this->external_name(),
407 host->external_name(),
408 msg);
409 }
410 // set dynamic nest host
411 _nest_host = host;
412 // Record dependency to keep nest host from being unloaded before this class.
413 ClassLoaderData* this_key = class_loader_data();
414 assert(this_key != nullptr, "sanity");
415 this_key->record_dependency(host);
416 }
417
418 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
419 // or we are k's nest_host - all of which is covered by comparing the two
420 // resolved_nest_hosts.
421 // Any exceptions (i.e. VMEs) are propagated.
422 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
423
424 assert(this != k, "this should be handled by higher-level code");
425
426 // Per JVMS 5.4.4 we first resolve and validate the current class, then
427 // the target class k.
428
429 InstanceKlass* cur_host = nest_host(CHECK_false);
430 if (cur_host == nullptr) {
431 return false;
432 }
433
434 Klass* k_nest_host = k->nest_host(CHECK_false);
435 if (k_nest_host == nullptr) {
436 return false;
437 }
438
439 bool access = (cur_host == k_nest_host);
440
441 ResourceMark rm(THREAD);
442 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
443 this->external_name(),
444 access ? "" : "NOT ",
445 k->external_name());
446 return access;
447 }
448
449 const char* InstanceKlass::nest_host_error() {
450 if (_nest_host_index == 0) {
451 return nullptr;
452 } else {
453 constantPoolHandle cph(Thread::current(), constants());
454 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
455 }
456 }
457
458 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
459 bool use_class_space, TRAPS) throw() {
460 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
461 }
462
463 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
464 const int size = InstanceKlass::size(parser.vtable_size(),
465 parser.itable_size(),
466 nonstatic_oop_map_size(parser.total_oop_map_count()),
467 parser.is_interface());
468
469 const Symbol* const class_name = parser.class_name();
470 assert(class_name != nullptr, "invariant");
471 ClassLoaderData* loader_data = parser.loader_data();
472 assert(loader_data != nullptr, "invariant");
473
474 InstanceKlass* ik;
475 const bool use_class_space = parser.klass_needs_narrow_id();
476
477 // Allocation
478 if (parser.is_instance_ref_klass()) {
479 // java.lang.ref.Reference
480 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
481 } else if (class_name == vmSymbols::java_lang_Class()) {
482 // mirror - java.lang.Class
483 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
484 } else if (is_stack_chunk_class(class_name, loader_data)) {
485 // stack chunk
486 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
487 } else if (is_class_loader(class_name, parser)) {
488 // class loader - java.lang.ClassLoader
489 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
490 } else {
491 // normal
492 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
493 }
494
495 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
496 assert(CompressedKlassPointers::is_encodable(ik),
497 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
498 }
499
500 // Check for pending exception before adding to the loader data and incrementing
501 // class count. Can get OOM here.
502 if (HAS_PENDING_EXCEPTION) {
503 return nullptr;
504 }
505
506 return ik;
507 }
508
509
510 // copy method ordering from resource area to Metaspace
511 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
512 if (m != nullptr) {
513 // allocate a new array and copy contents (memcpy?)
514 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
515 for (int i = 0; i < m->length(); i++) {
516 _method_ordering->at_put(i, m->at(i));
517 }
518 } else {
519 _method_ordering = Universe::the_empty_int_array();
520 }
521 }
522
523 // create a new array of vtable_indices for default methods
524 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
525 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
526 assert(default_vtable_indices() == nullptr, "only create once");
527 set_default_vtable_indices(vtable_indices);
528 return vtable_indices;
529 }
530
531
532 InstanceKlass::InstanceKlass() {
533 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
534 }
535
536 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
537 Klass(kind),
538 _nest_members(nullptr),
539 _nest_host(nullptr),
540 _permitted_subclasses(nullptr),
541 _record_components(nullptr),
542 _static_field_size(parser.static_field_size()),
543 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
544 _itable_len(parser.itable_size()),
545 _nest_host_index(0),
546 _init_state(allocated),
547 _reference_type(reference_type),
548 _init_thread(nullptr)
549 {
550 set_vtable_length(parser.vtable_size());
551 set_access_flags(parser.access_flags());
552 if (parser.is_hidden()) set_is_hidden();
553 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
554 false));
555
556 assert(nullptr == _methods, "underlying memory not zeroed?");
557 assert(is_instance_klass(), "is layout incorrect?");
558 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
559 }
560
561 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
562 Array<Method*>* methods) {
563 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
564 !methods->is_shared()) {
565 for (int i = 0; i < methods->length(); i++) {
566 Method* method = methods->at(i);
567 if (method == nullptr) continue; // maybe null if error processing
568 // Only want to delete methods that are not executing for RedefineClasses.
569 // The previous version will point to them so they're not totally dangling
570 assert (!method->on_stack(), "shouldn't be called with methods on stack");
571 MetadataFactory::free_metadata(loader_data, method);
572 }
573 MetadataFactory::free_array<Method*>(loader_data, methods);
574 }
575 }
576
577 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
578 const Klass* super_klass,
579 Array<InstanceKlass*>* local_interfaces,
580 Array<InstanceKlass*>* transitive_interfaces) {
581 // Only deallocate transitive interfaces if not empty, same as super class
582 // or same as local interfaces. See code in parseClassFile.
583 Array<InstanceKlass*>* ti = transitive_interfaces;
584 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
585 // check that the interfaces don't come from super class
586 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
587 InstanceKlass::cast(super_klass)->transitive_interfaces();
588 if (ti != sti && ti != nullptr && !ti->is_shared()) {
589 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
590 }
591 }
592
593 // local interfaces can be empty
594 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
595 local_interfaces != nullptr && !local_interfaces->is_shared()) {
596 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
597 }
598 }
599
600 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
601 Array<RecordComponent*>* record_components) {
602 if (record_components != nullptr && !record_components->is_shared()) {
603 for (int i = 0; i < record_components->length(); i++) {
604 RecordComponent* record_component = record_components->at(i);
605 MetadataFactory::free_metadata(loader_data, record_component);
606 }
607 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
608 }
609 }
610
611 // This function deallocates the metadata and C heap pointers that the
612 // InstanceKlass points to.
613 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
614 // Orphan the mirror first, CMS thinks it's still live.
615 if (java_mirror() != nullptr) {
616 java_lang_Class::set_klass(java_mirror(), nullptr);
617 }
618
619 // Also remove mirror from handles
620 loader_data->remove_handle(_java_mirror);
621
622 // Need to take this class off the class loader data list.
623 loader_data->remove_class(this);
624
625 // The array_klass for this class is created later, after error handling.
626 // For class redefinition, we keep the original class so this scratch class
627 // doesn't have an array class. Either way, assert that there is nothing
628 // to deallocate.
629 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
630
631 // Release C heap allocated data that this points to, which includes
632 // reference counting symbol names.
633 // Can't release the constant pool or MethodData C heap data here because the constant
634 // pool can be deallocated separately from the InstanceKlass for default methods and
635 // redefine classes. MethodData can also be released separately.
636 release_C_heap_structures(/* release_sub_metadata */ false);
637
638 deallocate_methods(loader_data, methods());
639 set_methods(nullptr);
640
641 deallocate_record_components(loader_data, record_components());
642 set_record_components(nullptr);
643
644 if (method_ordering() != nullptr &&
645 method_ordering() != Universe::the_empty_int_array() &&
646 !method_ordering()->is_shared()) {
647 MetadataFactory::free_array<int>(loader_data, method_ordering());
648 }
649 set_method_ordering(nullptr);
650
651 // default methods can be empty
652 if (default_methods() != nullptr &&
653 default_methods() != Universe::the_empty_method_array() &&
654 !default_methods()->is_shared()) {
655 MetadataFactory::free_array<Method*>(loader_data, default_methods());
656 }
657 // Do NOT deallocate the default methods, they are owned by superinterfaces.
658 set_default_methods(nullptr);
659
660 // default methods vtable indices can be empty
661 if (default_vtable_indices() != nullptr &&
662 !default_vtable_indices()->is_shared()) {
663 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
664 }
665 set_default_vtable_indices(nullptr);
666
667
668 // This array is in Klass, but remove it with the InstanceKlass since
669 // this place would be the only caller and it can share memory with transitive
670 // interfaces.
671 if (secondary_supers() != nullptr &&
672 secondary_supers() != Universe::the_empty_klass_array() &&
673 // see comments in compute_secondary_supers about the following cast
674 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
675 !secondary_supers()->is_shared()) {
676 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
677 }
678 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
679
680 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
681 set_transitive_interfaces(nullptr);
682 set_local_interfaces(nullptr);
683
684 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
685 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
686 }
687 set_fieldinfo_stream(nullptr);
688
689 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->is_shared()) {
690 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table());
691 }
692 set_fieldinfo_search_table(nullptr);
693
694 if (fields_status() != nullptr && !fields_status()->is_shared()) {
695 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
696 }
697 set_fields_status(nullptr);
698
699 // If a method from a redefined class is using this constant pool, don't
700 // delete it, yet. The new class's previous version will point to this.
701 if (constants() != nullptr) {
702 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
703 if (!constants()->is_shared()) {
704 MetadataFactory::free_metadata(loader_data, constants());
705 }
706 // Delete any cached resolution errors for the constant pool
707 SystemDictionary::delete_resolution_error(constants());
708
709 set_constants(nullptr);
710 }
711
712 if (inner_classes() != nullptr &&
713 inner_classes() != Universe::the_empty_short_array() &&
714 !inner_classes()->is_shared()) {
715 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
716 }
717 set_inner_classes(nullptr);
718
719 if (nest_members() != nullptr &&
720 nest_members() != Universe::the_empty_short_array() &&
721 !nest_members()->is_shared()) {
722 MetadataFactory::free_array<jushort>(loader_data, nest_members());
723 }
724 set_nest_members(nullptr);
725
726 if (permitted_subclasses() != nullptr &&
727 permitted_subclasses() != Universe::the_empty_short_array() &&
728 !permitted_subclasses()->is_shared()) {
729 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
730 }
731 set_permitted_subclasses(nullptr);
732
733 // We should deallocate the Annotations instance if it's not in shared spaces.
734 if (annotations() != nullptr && !annotations()->is_shared()) {
735 MetadataFactory::free_metadata(loader_data, annotations());
736 }
737 set_annotations(nullptr);
738
739 SystemDictionaryShared::handle_class_unloading(this);
740
741 #if INCLUDE_CDS_JAVA_HEAP
742 if (CDSConfig::is_dumping_heap()) {
743 HeapShared::remove_scratch_objects(this);
744 }
745 #endif
746 }
747
748 bool InstanceKlass::is_record() const {
749 return _record_components != nullptr &&
750 is_final() &&
751 java_super() == vmClasses::Record_klass();
752 }
753
754 bool InstanceKlass::is_sealed() const {
755 return _permitted_subclasses != nullptr &&
756 _permitted_subclasses != Universe::the_empty_short_array();
757 }
758
759 // JLS 8.9: An enum class is either implicitly final and derives
760 // from java.lang.Enum, or else is implicitly sealed to its
761 // anonymous subclasses. This query detects both kinds.
762 // It does not validate the finality or
763 // sealing conditions: it merely checks for a super of Enum.
764 // This is sufficient for recognizing well-formed enums.
765 bool InstanceKlass::is_enum_subclass() const {
766 InstanceKlass* s = java_super();
767 return (s == vmClasses::Enum_klass() ||
768 (s != nullptr && s->java_super() == vmClasses::Enum_klass()));
769 }
770
771 bool InstanceKlass::should_be_initialized() const {
772 return !is_initialized();
773 }
774
775 klassItable InstanceKlass::itable() const {
776 return klassItable(const_cast<InstanceKlass*>(this));
777 }
778
779 // JVMTI spec thinks there are signers and protection domain in the
780 // instanceKlass. These accessors pretend these fields are there.
781 // The hprof specification also thinks these fields are in InstanceKlass.
782 oop InstanceKlass::protection_domain() const {
783 // return the protection_domain from the mirror
784 return java_lang_Class::protection_domain(java_mirror());
785 }
786
787 objArrayOop InstanceKlass::signers() const {
788 // return the signers from the mirror
789 return java_lang_Class::signers(java_mirror());
790 }
791
792 oop InstanceKlass::init_lock() const {
793 // return the init lock from the mirror
794 oop lock = java_lang_Class::init_lock(java_mirror());
795 // Prevent reordering with any access of initialization state
796 OrderAccess::loadload();
797 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
798 "only fully initialized state can have a null lock");
799 return lock;
800 }
801
802 // Set the initialization lock to null so the object can be GC'ed. Any racing
803 // threads to get this lock will see a null lock and will not lock.
804 // That's okay because they all check for initialized state after getting
805 // the lock and return.
806 void InstanceKlass::fence_and_clear_init_lock() {
807 // make sure previous stores are all done, notably the init_state.
808 OrderAccess::storestore();
809 java_lang_Class::clear_init_lock(java_mirror());
810 assert(!is_not_initialized(), "class must be initialized now");
811 }
812
813
814 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
815 // process. The step comments refers to the procedure described in that section.
816 // Note: implementation moved to static method to expose the this pointer.
817 void InstanceKlass::initialize(TRAPS) {
818 if (this->should_be_initialized()) {
819 initialize_impl(CHECK);
820 // Note: at this point the class may be initialized
821 // OR it may be in the state of being initialized
822 // in case of recursive initialization!
823 } else {
824 assert(is_initialized(), "sanity check");
825 }
826 }
827
828 #ifdef ASSERT
829 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const {
830 assert(has_aot_initialized_mirror(), "must be");
831
832 InstanceKlass* s = java_super();
833 if (s != nullptr) {
834 DEBUG_ONLY(ResourceMark rm);
835 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized",
836 s->external_name(), external_name());
837 s->assert_no_clinit_will_run_for_aot_initialized_class();
838 }
839
840 Array<InstanceKlass*>* interfaces = local_interfaces();
841 int len = interfaces->length();
842 for (int i = 0; i < len; i++) {
843 InstanceKlass* intf = interfaces->at(i);
844 if (!intf->is_initialized()) {
845 ResourceMark rm;
846 // Note: an interface needs to be marked as is_initialized() only if
847 // - it has a <clinit>
848 // - it has declared a default method.
849 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false),
850 "uninitialized super interface %s of aot-inited class %s must not have <clinit>",
851 intf->external_name(), external_name());
852 }
853 }
854 }
855 #endif
856
857 #if INCLUDE_CDS
858 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) {
859 assert(has_aot_initialized_mirror(), "must be");
860 assert(CDSConfig::is_loading_heap(), "must be");
861 assert(CDSConfig::is_using_aot_linked_classes(), "must be");
862 assert_no_clinit_will_run_for_aot_initialized_class();
863
864 if (is_initialized()) {
865 return;
866 }
867
868 if (is_runtime_setup_required()) {
869 // Need to take the slow path, which will call the runtimeSetup() function instead
870 // of <clinit>
871 initialize(CHECK);
872 return;
873 }
874 if (log_is_enabled(Info, aot, init)) {
875 ResourceMark rm;
876 log_info(aot, init)("%s (aot-inited)", external_name());
877 }
878
879 link_class(CHECK);
880
881 #ifdef ASSERT
882 {
883 Handle h_init_lock(THREAD, init_lock());
884 ObjectLocker ol(h_init_lock, THREAD);
885 assert(!is_initialized(), "sanity");
886 assert(!is_being_initialized(), "sanity");
887 assert(!is_in_error_state(), "sanity");
888 }
889 #endif
890
891 set_init_thread(THREAD);
892 set_initialization_state_and_notify(fully_initialized, CHECK);
893 }
894 #endif
895
896 bool InstanceKlass::verify_code(TRAPS) {
897 // 1) Verify the bytecodes
898 return Verifier::verify(this, should_verify_class(), THREAD);
899 }
900
901 void InstanceKlass::link_class(TRAPS) {
902 assert(is_loaded(), "must be loaded");
903 if (!is_linked()) {
904 link_class_impl(CHECK);
905 }
906 }
907
908 // Called to verify that a class can link during initialization, without
909 // throwing a VerifyError.
910 bool InstanceKlass::link_class_or_fail(TRAPS) {
911 assert(is_loaded(), "must be loaded");
912 if (!is_linked()) {
913 link_class_impl(CHECK_false);
914 }
915 return is_linked();
916 }
917
918 bool InstanceKlass::link_class_impl(TRAPS) {
919 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
920 // This is for CDS static dump only -- we use the in_error_state to indicate that
921 // the class has failed verification. Throwing the NoClassDefFoundError here is just
922 // a convenient way to stop repeat attempts to verify the same (bad) class.
923 //
924 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
925 // if we are executing Java code. This is not a problem for CDS dumping phase since
926 // it doesn't execute any Java code.
927 ResourceMark rm(THREAD);
928 // Names are all known to be < 64k so we know this formatted message is not excessively large.
929 Exceptions::fthrow(THREAD_AND_LOCATION,
930 vmSymbols::java_lang_NoClassDefFoundError(),
931 "Class %s, or one of its supertypes, failed class initialization",
932 external_name());
933 return false;
934 }
935 // return if already verified
936 if (is_linked()) {
937 return true;
938 }
939
940 // Timing
941 // timer handles recursion
942 JavaThread* jt = THREAD;
943
944 // link super class before linking this class
945 Klass* super_klass = super();
946 if (super_klass != nullptr) {
947 if (super_klass->is_interface()) { // check if super class is an interface
948 ResourceMark rm(THREAD);
949 // Names are all known to be < 64k so we know this formatted message is not excessively large.
950 Exceptions::fthrow(
951 THREAD_AND_LOCATION,
952 vmSymbols::java_lang_IncompatibleClassChangeError(),
953 "class %s has interface %s as super class",
954 external_name(),
955 super_klass->external_name()
956 );
957 return false;
958 }
959
960 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
961 ik_super->link_class_impl(CHECK_false);
962 }
963
964 // link all interfaces implemented by this class before linking this class
965 Array<InstanceKlass*>* interfaces = local_interfaces();
966 int num_interfaces = interfaces->length();
967 for (int index = 0; index < num_interfaces; index++) {
968 InstanceKlass* interk = interfaces->at(index);
969 interk->link_class_impl(CHECK_false);
970 }
971
972 // in case the class is linked in the process of linking its superclasses
973 if (is_linked()) {
974 return true;
975 }
976
977 // trace only the link time for this klass that includes
978 // the verification time
979 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
980 ClassLoader::perf_class_link_selftime(),
981 ClassLoader::perf_classes_linked(),
982 jt->get_thread_stat()->perf_recursion_counts_addr(),
983 jt->get_thread_stat()->perf_timers_addr(),
984 PerfClassTraceTime::CLASS_LINK);
985
986 // verification & rewriting
987 {
988 HandleMark hm(THREAD);
989 Handle h_init_lock(THREAD, init_lock());
990 ObjectLocker ol(h_init_lock, jt);
991 // rewritten will have been set if loader constraint error found
992 // on an earlier link attempt
993 // don't verify or rewrite if already rewritten
994 //
995
996 if (!is_linked()) {
997 if (!is_rewritten()) {
998 if (is_shared()) {
999 assert(!verified_at_dump_time(), "must be");
1000 }
1001 {
1002 bool verify_ok = verify_code(THREAD);
1003 if (!verify_ok) {
1004 return false;
1005 }
1006 }
1007
1008 // Just in case a side-effect of verify linked this class already
1009 // (which can sometimes happen since the verifier loads classes
1010 // using custom class loaders, which are free to initialize things)
1011 if (is_linked()) {
1012 return true;
1013 }
1014
1015 // also sets rewritten
1016 rewrite_class(CHECK_false);
1017 } else if (is_shared()) {
1018 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1019 }
1020
1021 // relocate jsrs and link methods after they are all rewritten
1022 link_methods(CHECK_false);
1023
1024 // Initialize the vtable and interface table after
1025 // methods have been rewritten since rewrite may
1026 // fabricate new Method*s.
1027 // also does loader constraint checking
1028 //
1029 // initialize_vtable and initialize_itable need to be rerun
1030 // for a shared class if
1031 // 1) the class is loaded by custom class loader or
1032 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1033 // 3) the class was not verified during dump time
1034 bool need_init_table = true;
1035 if (is_shared() && verified_at_dump_time() &&
1036 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1037 need_init_table = false;
1038 }
1039 if (need_init_table) {
1040 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1041 itable().initialize_itable_and_check_constraints(CHECK_false);
1042 }
1043 #ifdef ASSERT
1044 vtable().verify(tty, true);
1045 // In case itable verification is ever added.
1046 // itable().verify(tty, true);
1047 #endif
1048 if (Universe::is_fully_initialized()) {
1049 DeoptimizationScope deopt_scope;
1050 {
1051 // Now mark all code that assumes the class is not linked.
1052 // Set state under the Compile_lock also.
1053 MutexLocker ml(THREAD, Compile_lock);
1054
1055 set_init_state(linked);
1056 CodeCache::mark_dependents_on(&deopt_scope, this);
1057 }
1058 // Perform the deopt handshake outside Compile_lock.
1059 deopt_scope.deoptimize_marked();
1060 } else {
1061 set_init_state(linked);
1062 }
1063 if (JvmtiExport::should_post_class_prepare()) {
1064 JvmtiExport::post_class_prepare(THREAD, this);
1065 }
1066 }
1067 }
1068 return true;
1069 }
1070
1071 // Rewrite the byte codes of all of the methods of a class.
1072 // The rewriter must be called exactly once. Rewriting must happen after
1073 // verification but before the first method of the class is executed.
1074 void InstanceKlass::rewrite_class(TRAPS) {
1075 assert(is_loaded(), "must be loaded");
1076 if (is_rewritten()) {
1077 assert(is_shared(), "rewriting an unshared class?");
1078 return;
1079 }
1080 Rewriter::rewrite(this, CHECK);
1081 set_rewritten();
1082 }
1083
1084 // Now relocate and link method entry points after class is rewritten.
1085 // This is outside is_rewritten flag. In case of an exception, it can be
1086 // executed more than once.
1087 void InstanceKlass::link_methods(TRAPS) {
1088 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1089
1090 int len = methods()->length();
1091 for (int i = len-1; i >= 0; i--) {
1092 methodHandle m(THREAD, methods()->at(i));
1093
1094 // Set up method entry points for compiler and interpreter .
1095 m->link_method(m, CHECK);
1096 }
1097 }
1098
1099 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1100 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1101 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1102 for (int i = 0; i < local_interfaces()->length(); ++i) {
1103 InstanceKlass* ik = local_interfaces()->at(i);
1104
1105 // Initialization is depth first search ie. we start with top of the inheritance tree
1106 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1107 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1108 if (ik->has_nonstatic_concrete_methods()) {
1109 ik->initialize_super_interfaces(CHECK);
1110 }
1111
1112 // Only initialize() interfaces that "declare" concrete methods.
1113 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1114 ik->initialize(CHECK);
1115 }
1116 }
1117 }
1118
1119 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1120 static InitializationErrorTable* _initialization_error_table;
1121
1122 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1123 // Create the same exception with a message indicating the thread name,
1124 // and the StackTraceElements.
1125 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1126 ResourceMark rm(current);
1127 if (init_error.is_null()) {
1128 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1129
1130 // We failed to create the new exception, most likely due to either out-of-memory or
1131 // a stackoverflow error. If the original exception was either of those then we save
1132 // the shared, pre-allocated, stackless, instance of that exception.
1133 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1134 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1135 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1136 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1137 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1138 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1139 } else {
1140 return;
1141 }
1142 }
1143
1144 MutexLocker ml(current, ClassInitError_lock);
1145 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1146 bool created;
1147 if (_initialization_error_table == nullptr) {
1148 _initialization_error_table = new (mtClass) InitializationErrorTable();
1149 }
1150 _initialization_error_table->put_if_absent(this, elem, &created);
1151 assert(created, "Initialization is single threaded");
1152 log_trace(class, init)("Initialization error added for class %s", external_name());
1153 }
1154
1155 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1156 MutexLocker ml(current, ClassInitError_lock);
1157 if (_initialization_error_table == nullptr) {
1158 return nullptr;
1159 }
1160 OopHandle* h = _initialization_error_table->get(this);
1161 return (h != nullptr) ? h->resolve() : nullptr;
1162 }
1163
1164 // Need to remove entries for unloaded classes.
1165 void InstanceKlass::clean_initialization_error_table() {
1166 struct InitErrorTableCleaner {
1167 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1168 if (!ik->is_loader_alive()) {
1169 h.release(Universe::vm_global());
1170 return true;
1171 } else {
1172 return false;
1173 }
1174 }
1175 };
1176
1177 assert_locked_or_safepoint(ClassInitError_lock);
1178 InitErrorTableCleaner cleaner;
1179 if (_initialization_error_table != nullptr) {
1180 _initialization_error_table->unlink(&cleaner);
1181 }
1182 }
1183
1184 void InstanceKlass::initialize_impl(TRAPS) {
1185 HandleMark hm(THREAD);
1186
1187 // Make sure klass is linked (verified) before initialization
1188 // A class could already be verified, since it has been reflected upon.
1189 link_class(CHECK);
1190
1191 DTRACE_CLASSINIT_PROBE(required, -1);
1192
1193 bool wait = false;
1194
1195 JavaThread* jt = THREAD;
1196
1197 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1198
1199 // refer to the JVM book page 47 for description of steps
1200 // Step 1
1201 {
1202 Handle h_init_lock(THREAD, init_lock());
1203 ObjectLocker ol(h_init_lock, jt);
1204
1205 // Step 2
1206 // If we were to use wait() instead of waitInterruptibly() then
1207 // we might end up throwing IE from link/symbol resolution sites
1208 // that aren't expected to throw. This would wreak havoc. See 6320309.
1209 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1210 if (debug_logging_enabled) {
1211 ResourceMark rm(jt);
1212 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1213 jt->name(), external_name(), init_thread_name());
1214 }
1215 wait = true;
1216 jt->set_class_to_be_initialized(this);
1217 ol.wait_uninterruptibly(jt);
1218 jt->set_class_to_be_initialized(nullptr);
1219 }
1220
1221 // Step 3
1222 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1223 if (debug_logging_enabled) {
1224 ResourceMark rm(jt);
1225 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1226 jt->name(), external_name());
1227 }
1228 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1229 return;
1230 }
1231
1232 // Step 4
1233 if (is_initialized()) {
1234 if (debug_logging_enabled) {
1235 ResourceMark rm(jt);
1236 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1237 jt->name(), external_name());
1238 }
1239 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1240 return;
1241 }
1242
1243 // Step 5
1244 if (is_in_error_state()) {
1245 if (debug_logging_enabled) {
1246 ResourceMark rm(jt);
1247 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1248 jt->name(), external_name());
1249 }
1250
1251 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1252 ResourceMark rm(THREAD);
1253 Handle cause(THREAD, get_initialization_error(THREAD));
1254
1255 stringStream ss;
1256 ss.print("Could not initialize class %s", external_name());
1257 if (cause.is_null()) {
1258 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1259 } else {
1260 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1261 ss.as_string(), cause);
1262 }
1263 } else {
1264
1265 // Step 6
1266 set_init_state(being_initialized);
1267 set_init_thread(jt);
1268 if (debug_logging_enabled) {
1269 ResourceMark rm(jt);
1270 log_debug(class, init)("Thread \"%s\" is initializing %s",
1271 jt->name(), external_name());
1272 }
1273 }
1274 }
1275
1276 // Step 7
1277 // Next, if C is a class rather than an interface, initialize it's super class and super
1278 // interfaces.
1279 if (!is_interface()) {
1280 Klass* super_klass = super();
1281 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1282 super_klass->initialize(THREAD);
1283 }
1284 // If C implements any interface that declares a non-static, concrete method,
1285 // the initialization of C triggers initialization of its super interfaces.
1286 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1287 // having a superinterface that declares, non-static, concrete methods
1288 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1289 initialize_super_interfaces(THREAD);
1290 }
1291
1292 // If any exceptions, complete abruptly, throwing the same exception as above.
1293 if (HAS_PENDING_EXCEPTION) {
1294 Handle e(THREAD, PENDING_EXCEPTION);
1295 CLEAR_PENDING_EXCEPTION;
1296 {
1297 EXCEPTION_MARK;
1298 add_initialization_error(THREAD, e);
1299 // Locks object, set state, and notify all waiting threads
1300 set_initialization_state_and_notify(initialization_error, THREAD);
1301 CLEAR_PENDING_EXCEPTION;
1302 }
1303 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1304 THROW_OOP(e());
1305 }
1306 }
1307
1308
1309 // Step 8
1310 {
1311 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1312 if (class_initializer() != nullptr) {
1313 // Timer includes any side effects of class initialization (resolution,
1314 // etc), but not recursive entry into call_class_initializer().
1315 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1316 ClassLoader::perf_class_init_selftime(),
1317 ClassLoader::perf_classes_inited(),
1318 jt->get_thread_stat()->perf_recursion_counts_addr(),
1319 jt->get_thread_stat()->perf_timers_addr(),
1320 PerfClassTraceTime::CLASS_CLINIT);
1321 call_class_initializer(THREAD);
1322 } else {
1323 // The elapsed time is so small it's not worth counting.
1324 if (UsePerfData) {
1325 ClassLoader::perf_classes_inited()->inc();
1326 }
1327 call_class_initializer(THREAD);
1328 }
1329 }
1330
1331 // Step 9
1332 if (!HAS_PENDING_EXCEPTION) {
1333 set_initialization_state_and_notify(fully_initialized, CHECK);
1334 DEBUG_ONLY(vtable().verify(tty, true);)
1335 CompilationPolicy::replay_training_at_init(this, THREAD);
1336 }
1337 else {
1338 // Step 10 and 11
1339 Handle e(THREAD, PENDING_EXCEPTION);
1340 CLEAR_PENDING_EXCEPTION;
1341 // JVMTI has already reported the pending exception
1342 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1343 JvmtiExport::clear_detected_exception(jt);
1344 {
1345 EXCEPTION_MARK;
1346 add_initialization_error(THREAD, e);
1347 set_initialization_state_and_notify(initialization_error, THREAD);
1348 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1349 // JVMTI has already reported the pending exception
1350 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1351 JvmtiExport::clear_detected_exception(jt);
1352 }
1353 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1354 if (e->is_a(vmClasses::Error_klass())) {
1355 THROW_OOP(e());
1356 } else {
1357 JavaCallArguments args(e);
1358 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1359 vmSymbols::throwable_void_signature(),
1360 &args);
1361 }
1362 }
1363 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1364 }
1365
1366
1367 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1368 Handle h_init_lock(THREAD, init_lock());
1369 if (h_init_lock() != nullptr) {
1370 ObjectLocker ol(h_init_lock, THREAD);
1371 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1372 set_init_state(state);
1373 fence_and_clear_init_lock();
1374 ol.notify_all(CHECK);
1375 } else {
1376 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1377 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1378 set_init_state(state);
1379 }
1380 }
1381
1382 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1383 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1384 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1385 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1386
1387 DeoptimizationScope deopt_scope;
1388 {
1389 MutexLocker ml(current, Compile_lock);
1390
1391 set_init_state(InstanceKlass::loaded);
1392 // make sure init_state store is already done.
1393 // The compiler reads the hierarchy outside of the Compile_lock.
1394 // Access ordering is used to add to hierarchy.
1395
1396 // Link into hierarchy.
1397 append_to_sibling_list(); // add to superklass/sibling list
1398 process_interfaces(); // handle all "implements" declarations
1399
1400 // Now mark all code that depended on old class hierarchy.
1401 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1402 if (Universe::is_fully_initialized()) {
1403 CodeCache::mark_dependents_on(&deopt_scope, this);
1404 }
1405 }
1406 // Perform the deopt handshake outside Compile_lock.
1407 deopt_scope.deoptimize_marked();
1408 }
1409
1410
1411 InstanceKlass* InstanceKlass::implementor() const {
1412 InstanceKlass* volatile* ik = adr_implementor();
1413 if (ik == nullptr) {
1414 return nullptr;
1415 } else {
1416 // This load races with inserts, and therefore needs acquire.
1417 InstanceKlass* ikls = Atomic::load_acquire(ik);
1418 if (ikls != nullptr && !ikls->is_loader_alive()) {
1419 return nullptr; // don't return unloaded class
1420 } else {
1421 return ikls;
1422 }
1423 }
1424 }
1425
1426
1427 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1428 assert_locked_or_safepoint(Compile_lock);
1429 assert(is_interface(), "not interface");
1430 InstanceKlass* volatile* addr = adr_implementor();
1431 assert(addr != nullptr, "null addr");
1432 if (addr != nullptr) {
1433 Atomic::release_store(addr, ik);
1434 }
1435 }
1436
1437 int InstanceKlass::nof_implementors() const {
1438 InstanceKlass* ik = implementor();
1439 if (ik == nullptr) {
1440 return 0;
1441 } else if (ik != this) {
1442 return 1;
1443 } else {
1444 return 2;
1445 }
1446 }
1447
1448 // The embedded _implementor field can only record one implementor.
1449 // When there are more than one implementors, the _implementor field
1450 // is set to the interface Klass* itself. Following are the possible
1451 // values for the _implementor field:
1452 // null - no implementor
1453 // implementor Klass* - one implementor
1454 // self - more than one implementor
1455 //
1456 // The _implementor field only exists for interfaces.
1457 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1458 if (Universe::is_fully_initialized()) {
1459 assert_lock_strong(Compile_lock);
1460 }
1461 assert(is_interface(), "not interface");
1462 // Filter out my subinterfaces.
1463 // (Note: Interfaces are never on the subklass list.)
1464 if (ik->is_interface()) return;
1465
1466 // Filter out subclasses whose supers already implement me.
1467 // (Note: CHA must walk subclasses of direct implementors
1468 // in order to locate indirect implementors.)
1469 InstanceKlass* super_ik = ik->java_super();
1470 if (super_ik != nullptr && super_ik->implements_interface(this))
1471 // We only need to check one immediate superclass, since the
1472 // implements_interface query looks at transitive_interfaces.
1473 // Any supers of the super have the same (or fewer) transitive_interfaces.
1474 return;
1475
1476 InstanceKlass* iklass = implementor();
1477 if (iklass == nullptr) {
1478 set_implementor(ik);
1479 } else if (iklass != this && iklass != ik) {
1480 // There is already an implementor. Use itself as an indicator of
1481 // more than one implementors.
1482 set_implementor(this);
1483 }
1484
1485 // The implementor also implements the transitive_interfaces
1486 for (int index = 0; index < local_interfaces()->length(); index++) {
1487 local_interfaces()->at(index)->add_implementor(ik);
1488 }
1489 }
1490
1491 void InstanceKlass::init_implementor() {
1492 if (is_interface()) {
1493 set_implementor(nullptr);
1494 }
1495 }
1496
1497
1498 void InstanceKlass::process_interfaces() {
1499 // link this class into the implementors list of every interface it implements
1500 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1501 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1502 InstanceKlass* interf = local_interfaces()->at(i);
1503 assert(interf->is_interface(), "expected interface");
1504 interf->add_implementor(this);
1505 }
1506 }
1507
1508 bool InstanceKlass::can_be_primary_super_slow() const {
1509 if (is_interface())
1510 return false;
1511 else
1512 return Klass::can_be_primary_super_slow();
1513 }
1514
1515 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1516 Array<InstanceKlass*>* transitive_interfaces) {
1517 // The secondaries are the implemented interfaces.
1518 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1519 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1520 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1521 int num_secondaries = num_extra_slots + interfaces->length();
1522 if (num_secondaries == 0) {
1523 // Must share this for correct bootstrapping!
1524 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1525 return nullptr;
1526 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1527 // We will reuse the transitive interfaces list if we're certain
1528 // it's in hash order.
1529 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1530 set_secondary_supers(interfaces, bitmap);
1531 return nullptr;
1532 }
1533 // Copy transitive interfaces to a temporary growable array to be constructed
1534 // into the secondary super list with extra slots.
1535 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1536 for (int i = 0; i < interfaces->length(); i++) {
1537 secondaries->push(interfaces->at(i));
1538 }
1539 return secondaries;
1540 }
1541
1542 bool InstanceKlass::implements_interface(Klass* k) const {
1543 if (this == k) return true;
1544 assert(k->is_interface(), "should be an interface class");
1545 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1546 if (transitive_interfaces()->at(i) == k) {
1547 return true;
1548 }
1549 }
1550 return false;
1551 }
1552
1553 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1554 // Verify direct super interface
1555 if (this == k) return true;
1556 assert(k->is_interface(), "should be an interface class");
1557 for (int i = 0; i < local_interfaces()->length(); i++) {
1558 if (local_interfaces()->at(i) == k) {
1559 return true;
1560 }
1561 }
1562 return false;
1563 }
1564
1565 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1566 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1567 size_t size = objArrayOopDesc::object_size(length);
1568 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1569 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1570 /* do_zero */ true, CHECK_NULL);
1571 return o;
1572 }
1573
1574 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1575 if (TraceFinalizerRegistration) {
1576 tty->print("Registered ");
1577 i->print_value_on(tty);
1578 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1579 }
1580 instanceHandle h_i(THREAD, i);
1581 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1582 JavaValue result(T_VOID);
1583 JavaCallArguments args(h_i);
1584 methodHandle mh(THREAD, Universe::finalizer_register_method());
1585 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1586 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1587 return h_i();
1588 }
1589
1590 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1591 assert(!is_abstract() && !is_interface(), "Should not create this object");
1592 size_t size = size_helper(); // Query before forming handle.
1593 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1594 }
1595
1596 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1597 Klass* k = java_lang_Class::as_Klass(java_class);
1598 if (k == nullptr) {
1599 ResourceMark rm(THREAD);
1600 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1601 }
1602 InstanceKlass* ik = cast(k);
1603 ik->check_valid_for_instantiation(false, CHECK_NULL);
1604 ik->initialize(CHECK_NULL);
1605 return ik->allocate_instance(THREAD);
1606 }
1607
1608 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1609 return instanceHandle(THREAD, allocate_instance(THREAD));
1610 }
1611
1612 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1613 if (is_interface() || is_abstract()) {
1614 ResourceMark rm(THREAD);
1615 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1616 : vmSymbols::java_lang_InstantiationException(), external_name());
1617 }
1618 if (this == vmClasses::Class_klass()) {
1619 ResourceMark rm(THREAD);
1620 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1621 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1622 }
1623 }
1624
1625 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1626 // Need load-acquire for lock-free read
1627 if (array_klasses_acquire() == nullptr) {
1628
1629 // Recursively lock array allocation
1630 RecursiveLocker rl(MultiArray_lock, THREAD);
1631
1632 // Check if another thread created the array klass while we were waiting for the lock.
1633 if (array_klasses() == nullptr) {
1634 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1635 // use 'release' to pair with lock-free load
1636 release_set_array_klasses(k);
1637 }
1638 }
1639
1640 // array_klasses() will always be set at this point
1641 ObjArrayKlass* ak = array_klasses();
1642 assert(ak != nullptr, "should be set");
1643 return ak->array_klass(n, THREAD);
1644 }
1645
1646 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1647 // Need load-acquire for lock-free read
1648 ObjArrayKlass* oak = array_klasses_acquire();
1649 if (oak == nullptr) {
1650 return nullptr;
1651 } else {
1652 return oak->array_klass_or_null(n);
1653 }
1654 }
1655
1656 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1657 return array_klass(1, THREAD);
1658 }
1659
1660 ArrayKlass* InstanceKlass::array_klass_or_null() {
1661 return array_klass_or_null(1);
1662 }
1663
1664 static int call_class_initializer_counter = 0; // for debugging
1665
1666 Method* InstanceKlass::class_initializer() const {
1667 Method* clinit = find_method(
1668 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1669 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1670 return clinit;
1671 }
1672 return nullptr;
1673 }
1674
1675 void InstanceKlass::call_class_initializer(TRAPS) {
1676 if (ReplayCompiles &&
1677 (ReplaySuppressInitializers == 1 ||
1678 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1679 // Hide the existence of the initializer for the purpose of replaying the compile
1680 return;
1681 }
1682
1683 #if INCLUDE_CDS
1684 // This is needed to ensure the consistency of the archived heap objects.
1685 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1686 AOTClassInitializer::call_runtime_setup(THREAD, this);
1687 return;
1688 } else if (has_archived_enum_objs()) {
1689 assert(is_shared(), "must be");
1690 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1691 if (initialized) {
1692 return;
1693 }
1694 }
1695 #endif
1696
1697 methodHandle h_method(THREAD, class_initializer());
1698 assert(!is_initialized(), "we cannot initialize twice");
1699 LogTarget(Info, class, init) lt;
1700 if (lt.is_enabled()) {
1701 ResourceMark rm(THREAD);
1702 LogStream ls(lt);
1703 ls.print("%d Initializing ", call_class_initializer_counter++);
1704 name()->print_value_on(&ls);
1705 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1706 h_method() == nullptr ? "(no method)" : "", p2i(this),
1707 THREAD->name());
1708 }
1709 if (h_method() != nullptr) {
1710 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1711 JavaCallArguments args; // No arguments
1712 JavaValue result(T_VOID);
1713 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1714 }
1715 }
1716
1717 // If a class that implements this interface is initialized, is the JVM required
1718 // to first execute a <clinit> method declared in this interface,
1719 // or (if also_check_supers==true) any of the super types of this interface?
1720 //
1721 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1722 // an interface, then let SC be its superclass and let SI1, ..., SIn
1723 // be all superinterfaces of C (whether direct or indirect) that
1724 // declare at least one non-abstract, non-static method.
1725 //
1726 // So when an interface is initialized, it does not look at its
1727 // supers. But a proper class will ensure that all of its supers have
1728 // run their <clinit> methods, except that it disregards interfaces
1729 // that lack a non-static concrete method (i.e., a default method).
1730 // Therefore, you should probably call this method only when the
1731 // current class is a super of some proper class, not an interface.
1732 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1733 assert(is_interface(), "must be");
1734
1735 if (!has_nonstatic_concrete_methods()) {
1736 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1737 return false;
1738 }
1739
1740 // JVMS 5.5. Initialization
1741 // ...If C is an interface that declares a non-abstract,
1742 // non-static method, the initialization of a class that
1743 // implements C directly or indirectly.
1744 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1745 return true;
1746 }
1747 if (also_check_supers) {
1748 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1749 for (int i = 0; i < all_ifs->length(); ++i) {
1750 InstanceKlass* super_intf = all_ifs->at(i);
1751 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1752 return true;
1753 }
1754 }
1755 }
1756 return false;
1757 }
1758
1759 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1760 InterpreterOopMap* entry_for) {
1761 // Lazily create the _oop_map_cache at first request.
1762 // Load_acquire is needed to safely get instance published with CAS by another thread.
1763 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1764 if (oop_map_cache == nullptr) {
1765 // Try to install new instance atomically.
1766 oop_map_cache = new OopMapCache();
1767 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1768 if (other != nullptr) {
1769 // Someone else managed to install before us, ditch local copy and use the existing one.
1770 delete oop_map_cache;
1771 oop_map_cache = other;
1772 }
1773 }
1774 // _oop_map_cache is constant after init; lookup below does its own locking.
1775 oop_map_cache->lookup(method, bci, entry_for);
1776 }
1777
1778 bool InstanceKlass::contains_field_offset(int offset) {
1779 fieldDescriptor fd;
1780 return find_field_from_offset(offset, false, &fd);
1781 }
1782
1783 FieldInfo InstanceKlass::field(int index) const {
1784 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1785 if (fs.index() == index) {
1786 return fs.to_FieldInfo();
1787 }
1788 }
1789 fatal("Field not found");
1790 return FieldInfo();
1791 }
1792
1793 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1794 JavaFieldStream fs(this);
1795 if (fs.lookup(name, sig)) {
1796 assert(fs.name() == name, "name must match");
1797 assert(fs.signature() == sig, "signature must match");
1798 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1799 return true;
1800 }
1801 return false;
1802 }
1803
1804
1805 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1806 const int n = local_interfaces()->length();
1807 for (int i = 0; i < n; i++) {
1808 Klass* intf1 = local_interfaces()->at(i);
1809 assert(intf1->is_interface(), "just checking type");
1810 // search for field in current interface
1811 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1812 assert(fd->is_static(), "interface field must be static");
1813 return intf1;
1814 }
1815 // search for field in direct superinterfaces
1816 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1817 if (intf2 != nullptr) return intf2;
1818 }
1819 // otherwise field lookup fails
1820 return nullptr;
1821 }
1822
1823
1824 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1825 // search order according to newest JVM spec (5.4.3.2, p.167).
1826 // 1) search for field in current klass
1827 if (find_local_field(name, sig, fd)) {
1828 return const_cast<InstanceKlass*>(this);
1829 }
1830 // 2) search for field recursively in direct superinterfaces
1831 { Klass* intf = find_interface_field(name, sig, fd);
1832 if (intf != nullptr) return intf;
1833 }
1834 // 3) apply field lookup recursively if superclass exists
1835 { Klass* supr = super();
1836 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1837 }
1838 // 4) otherwise field lookup fails
1839 return nullptr;
1840 }
1841
1842
1843 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1844 // search order according to newest JVM spec (5.4.3.2, p.167).
1845 // 1) search for field in current klass
1846 if (find_local_field(name, sig, fd)) {
1847 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1848 }
1849 // 2) search for field recursively in direct superinterfaces
1850 if (is_static) {
1851 Klass* intf = find_interface_field(name, sig, fd);
1852 if (intf != nullptr) return intf;
1853 }
1854 // 3) apply field lookup recursively if superclass exists
1855 { Klass* supr = super();
1856 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1857 }
1858 // 4) otherwise field lookup fails
1859 return nullptr;
1860 }
1861
1862
1863 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1864 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1865 if (fs.offset() == offset) {
1866 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo());
1867 if (fd->is_static() == is_static) return true;
1868 }
1869 }
1870 return false;
1871 }
1872
1873
1874 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1875 Klass* klass = const_cast<InstanceKlass*>(this);
1876 while (klass != nullptr) {
1877 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1878 return true;
1879 }
1880 klass = klass->super();
1881 }
1882 return false;
1883 }
1884
1885
1886 void InstanceKlass::methods_do(void f(Method* method)) {
1887 // Methods aren't stable until they are loaded. This can be read outside
1888 // a lock through the ClassLoaderData for profiling
1889 // Redefined scratch classes are on the list and need to be cleaned
1890 if (!is_loaded() && !is_scratch_class()) {
1891 return;
1892 }
1893
1894 int len = methods()->length();
1895 for (int index = 0; index < len; index++) {
1896 Method* m = methods()->at(index);
1897 assert(m->is_method(), "must be method");
1898 f(m);
1899 }
1900 }
1901
1902
1903 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1904 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1905 if (fs.access_flags().is_static()) {
1906 fieldDescriptor& fd = fs.field_descriptor();
1907 cl->do_field(&fd);
1908 }
1909 }
1910 }
1911
1912
1913 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1914 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1915 if (fs.access_flags().is_static()) {
1916 fieldDescriptor& fd = fs.field_descriptor();
1917 f(&fd, mirror, CHECK);
1918 }
1919 }
1920 }
1921
1922 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1923 InstanceKlass* super = superklass();
1924 if (super != nullptr) {
1925 super->do_nonstatic_fields(cl);
1926 }
1927 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1928 fieldDescriptor& fd = fs.field_descriptor();
1929 if (!fd.is_static()) {
1930 cl->do_field(&fd);
1931 }
1932 }
1933 }
1934
1935 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) {
1936 return a->offset() - b->offset();
1937 }
1938
1939 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1940 InstanceKlass* super = superklass();
1941 if (super != nullptr) {
1942 super->print_nonstatic_fields(cl);
1943 }
1944 ResourceMark rm;
1945 // In DebugInfo nonstatic fields are sorted by offset.
1946 GrowableArray<FieldInfo> fields_sorted;
1947 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1948 if (!fs.access_flags().is_static()) {
1949 fields_sorted.push(fs.to_FieldInfo());
1950 }
1951 }
1952 int length = fields_sorted.length();
1953 if (length > 0) {
1954 fields_sorted.sort(compare_fields_by_offset);
1955 fieldDescriptor fd;
1956 for (int i = 0; i < length; i++) {
1957 fd.reinitialize(this, fields_sorted.at(i));
1958 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields");
1959 cl->do_field(&fd);
1960 }
1961 }
1962 }
1963
1964 #ifdef ASSERT
1965 static int linear_search(const Array<Method*>* methods,
1966 const Symbol* name,
1967 const Symbol* signature) {
1968 const int len = methods->length();
1969 for (int index = 0; index < len; index++) {
1970 const Method* const m = methods->at(index);
1971 assert(m->is_method(), "must be method");
1972 if (m->signature() == signature && m->name() == name) {
1973 return index;
1974 }
1975 }
1976 return -1;
1977 }
1978 #endif
1979
1980 bool InstanceKlass::_disable_method_binary_search = false;
1981
1982 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1983 int len = methods->length();
1984 int l = 0;
1985 int h = len - 1;
1986 while (l <= h) {
1987 Method* m = methods->at(l);
1988 if (m->name() == name) {
1989 return l;
1990 }
1991 l++;
1992 }
1993 return -1;
1994 }
1995
1996 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1997 if (_disable_method_binary_search) {
1998 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
1999 // At the final stage of dynamic dumping, the methods array may not be sorted
2000 // by ascending addresses of their names, so we can't use binary search anymore.
2001 // However, methods with the same name are still laid out consecutively inside the
2002 // methods array, so let's look for the first one that matches.
2003 return linear_search(methods, name);
2004 }
2005
2006 int len = methods->length();
2007 int l = 0;
2008 int h = len - 1;
2009
2010 // methods are sorted by ascending addresses of their names, so do binary search
2011 while (l <= h) {
2012 int mid = (l + h) >> 1;
2013 Method* m = methods->at(mid);
2014 assert(m->is_method(), "must be method");
2015 int res = m->name()->fast_compare(name);
2016 if (res == 0) {
2017 return mid;
2018 } else if (res < 0) {
2019 l = mid + 1;
2020 } else {
2021 h = mid - 1;
2022 }
2023 }
2024 return -1;
2025 }
2026
2027 // find_method looks up the name/signature in the local methods array
2028 Method* InstanceKlass::find_method(const Symbol* name,
2029 const Symbol* signature) const {
2030 return find_method_impl(name, signature,
2031 OverpassLookupMode::find,
2032 StaticLookupMode::find,
2033 PrivateLookupMode::find);
2034 }
2035
2036 Method* InstanceKlass::find_method_impl(const Symbol* name,
2037 const Symbol* signature,
2038 OverpassLookupMode overpass_mode,
2039 StaticLookupMode static_mode,
2040 PrivateLookupMode private_mode) const {
2041 return InstanceKlass::find_method_impl(methods(),
2042 name,
2043 signature,
2044 overpass_mode,
2045 static_mode,
2046 private_mode);
2047 }
2048
2049 // find_instance_method looks up the name/signature in the local methods array
2050 // and skips over static methods
2051 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2052 const Symbol* name,
2053 const Symbol* signature,
2054 PrivateLookupMode private_mode) {
2055 Method* const meth = InstanceKlass::find_method_impl(methods,
2056 name,
2057 signature,
2058 OverpassLookupMode::find,
2059 StaticLookupMode::skip,
2060 private_mode);
2061 assert(((meth == nullptr) || !meth->is_static()),
2062 "find_instance_method should have skipped statics");
2063 return meth;
2064 }
2065
2066 // find_instance_method looks up the name/signature in the local methods array
2067 // and skips over static methods
2068 Method* InstanceKlass::find_instance_method(const Symbol* name,
2069 const Symbol* signature,
2070 PrivateLookupMode private_mode) const {
2071 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2072 }
2073
2074 // Find looks up the name/signature in the local methods array
2075 // and filters on the overpass, static and private flags
2076 // This returns the first one found
2077 // note that the local methods array can have up to one overpass, one static
2078 // and one instance (private or not) with the same name/signature
2079 Method* InstanceKlass::find_local_method(const Symbol* name,
2080 const Symbol* signature,
2081 OverpassLookupMode overpass_mode,
2082 StaticLookupMode static_mode,
2083 PrivateLookupMode private_mode) const {
2084 return InstanceKlass::find_method_impl(methods(),
2085 name,
2086 signature,
2087 overpass_mode,
2088 static_mode,
2089 private_mode);
2090 }
2091
2092 // Find looks up the name/signature in the local methods array
2093 // and filters on the overpass, static and private flags
2094 // This returns the first one found
2095 // note that the local methods array can have up to one overpass, one static
2096 // and one instance (private or not) with the same name/signature
2097 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2098 const Symbol* name,
2099 const Symbol* signature,
2100 OverpassLookupMode overpass_mode,
2101 StaticLookupMode static_mode,
2102 PrivateLookupMode private_mode) {
2103 return InstanceKlass::find_method_impl(methods,
2104 name,
2105 signature,
2106 overpass_mode,
2107 static_mode,
2108 private_mode);
2109 }
2110
2111 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2112 const Symbol* name,
2113 const Symbol* signature) {
2114 return InstanceKlass::find_method_impl(methods,
2115 name,
2116 signature,
2117 OverpassLookupMode::find,
2118 StaticLookupMode::find,
2119 PrivateLookupMode::find);
2120 }
2121
2122 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2123 const Symbol* name,
2124 const Symbol* signature,
2125 OverpassLookupMode overpass_mode,
2126 StaticLookupMode static_mode,
2127 PrivateLookupMode private_mode) {
2128 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2129 return hit >= 0 ? methods->at(hit): nullptr;
2130 }
2131
2132 // true if method matches signature and conforms to skipping_X conditions.
2133 static bool method_matches(const Method* m,
2134 const Symbol* signature,
2135 bool skipping_overpass,
2136 bool skipping_static,
2137 bool skipping_private) {
2138 return ((m->signature() == signature) &&
2139 (!skipping_overpass || !m->is_overpass()) &&
2140 (!skipping_static || !m->is_static()) &&
2141 (!skipping_private || !m->is_private()));
2142 }
2143
2144 // Used directly for default_methods to find the index into the
2145 // default_vtable_indices, and indirectly by find_method
2146 // find_method_index looks in the local methods array to return the index
2147 // of the matching name/signature. If, overpass methods are being ignored,
2148 // the search continues to find a potential non-overpass match. This capability
2149 // is important during method resolution to prefer a static method, for example,
2150 // over an overpass method.
2151 // There is the possibility in any _method's array to have the same name/signature
2152 // for a static method, an overpass method and a local instance method
2153 // To correctly catch a given method, the search criteria may need
2154 // to explicitly skip the other two. For local instance methods, it
2155 // is often necessary to skip private methods
2156 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2157 const Symbol* name,
2158 const Symbol* signature,
2159 OverpassLookupMode overpass_mode,
2160 StaticLookupMode static_mode,
2161 PrivateLookupMode private_mode) {
2162 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2163 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2164 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2165 const int hit = quick_search(methods, name);
2166 if (hit != -1) {
2167 const Method* const m = methods->at(hit);
2168
2169 // Do linear search to find matching signature. First, quick check
2170 // for common case, ignoring overpasses if requested.
2171 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2172 return hit;
2173 }
2174
2175 // search downwards through overloaded methods
2176 int i;
2177 for (i = hit - 1; i >= 0; --i) {
2178 const Method* const m = methods->at(i);
2179 assert(m->is_method(), "must be method");
2180 if (m->name() != name) {
2181 break;
2182 }
2183 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2184 return i;
2185 }
2186 }
2187 // search upwards
2188 for (i = hit + 1; i < methods->length(); ++i) {
2189 const Method* const m = methods->at(i);
2190 assert(m->is_method(), "must be method");
2191 if (m->name() != name) {
2192 break;
2193 }
2194 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2195 return i;
2196 }
2197 }
2198 // not found
2199 #ifdef ASSERT
2200 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2201 linear_search(methods, name, signature);
2202 assert(-1 == index, "binary search should have found entry %d", index);
2203 #endif
2204 }
2205 return -1;
2206 }
2207
2208 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2209 return find_method_by_name(methods(), name, end);
2210 }
2211
2212 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2213 const Symbol* name,
2214 int* end_ptr) {
2215 assert(end_ptr != nullptr, "just checking");
2216 int start = quick_search(methods, name);
2217 int end = start + 1;
2218 if (start != -1) {
2219 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2220 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2221 *end_ptr = end;
2222 return start;
2223 }
2224 return -1;
2225 }
2226
2227 // uncached_lookup_method searches both the local class methods array and all
2228 // superclasses methods arrays, skipping any overpass methods in superclasses,
2229 // and possibly skipping private methods.
2230 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2231 const Symbol* signature,
2232 OverpassLookupMode overpass_mode,
2233 PrivateLookupMode private_mode) const {
2234 OverpassLookupMode overpass_local_mode = overpass_mode;
2235 const Klass* klass = this;
2236 while (klass != nullptr) {
2237 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2238 signature,
2239 overpass_local_mode,
2240 StaticLookupMode::find,
2241 private_mode);
2242 if (method != nullptr) {
2243 return method;
2244 }
2245 klass = klass->super();
2246 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2247 }
2248 return nullptr;
2249 }
2250
2251 #ifdef ASSERT
2252 // search through class hierarchy and return true if this class or
2253 // one of the superclasses was redefined
2254 bool InstanceKlass::has_redefined_this_or_super() const {
2255 const Klass* klass = this;
2256 while (klass != nullptr) {
2257 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2258 return true;
2259 }
2260 klass = klass->super();
2261 }
2262 return false;
2263 }
2264 #endif
2265
2266 // lookup a method in the default methods list then in all transitive interfaces
2267 // Do NOT return private or static methods
2268 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2269 Symbol* signature) const {
2270 Method* m = nullptr;
2271 if (default_methods() != nullptr) {
2272 m = find_method(default_methods(), name, signature);
2273 }
2274 // Look up interfaces
2275 if (m == nullptr) {
2276 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2277 }
2278 return m;
2279 }
2280
2281 // lookup a method in all the interfaces that this class implements
2282 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2283 // They should only be found in the initial InterfaceMethodRef
2284 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2285 Symbol* signature,
2286 DefaultsLookupMode defaults_mode) const {
2287 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2288 int num_ifs = all_ifs->length();
2289 InstanceKlass *ik = nullptr;
2290 for (int i = 0; i < num_ifs; i++) {
2291 ik = all_ifs->at(i);
2292 Method* m = ik->lookup_method(name, signature);
2293 if (m != nullptr && m->is_public() && !m->is_static() &&
2294 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2295 return m;
2296 }
2297 }
2298 return nullptr;
2299 }
2300
2301 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2302 :_st(st), _verbose(verbose) {
2303 ResourceMark rm;
2304 _st->print("%-18s ", "KlassAddr");
2305 _st->print("%-4s ", "Size");
2306 _st->print("%-20s ", "State");
2307 _st->print("%-7s ", "Flags");
2308 _st->print("%-5s ", "ClassName");
2309 _st->cr();
2310 }
2311
2312 void PrintClassClosure::do_klass(Klass* k) {
2313 ResourceMark rm;
2314 // klass pointer
2315 _st->print(PTR_FORMAT " ", p2i(k));
2316 // klass size
2317 _st->print("%4d ", k->size());
2318 // initialization state
2319 if (k->is_instance_klass()) {
2320 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2321 } else {
2322 _st->print("%-20s ","");
2323 }
2324 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2325 char buf[10];
2326 int i = 0;
2327 if (k->has_finalizer()) buf[i++] = 'F';
2328 if (k->is_instance_klass()) {
2329 InstanceKlass* ik = InstanceKlass::cast(k);
2330 if (ik->has_final_method()) buf[i++] = 'f';
2331 if (ik->is_rewritten()) buf[i++] = 'W';
2332 if (ik->is_contended()) buf[i++] = 'C';
2333 if (ik->has_been_redefined()) buf[i++] = 'R';
2334 if (ik->is_shared()) buf[i++] = 'S';
2335 }
2336 buf[i++] = '\0';
2337 _st->print("%-7s ", buf);
2338 // klass name
2339 _st->print("%-5s ", k->external_name());
2340 // end
2341 _st->cr();
2342 if (_verbose) {
2343 k->print_on(_st);
2344 }
2345 }
2346
2347 /* jni_id_for for jfieldIds only */
2348 JNIid* InstanceKlass::jni_id_for(int offset) {
2349 MutexLocker ml(JfieldIdCreation_lock);
2350 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2351 if (probe == nullptr) {
2352 // Allocate new static field identifier
2353 probe = new JNIid(this, offset, jni_ids());
2354 set_jni_ids(probe);
2355 }
2356 return probe;
2357 }
2358
2359 u2 InstanceKlass::enclosing_method_data(int offset) const {
2360 const Array<jushort>* const inner_class_list = inner_classes();
2361 if (inner_class_list == nullptr) {
2362 return 0;
2363 }
2364 const int length = inner_class_list->length();
2365 if (length % inner_class_next_offset == 0) {
2366 return 0;
2367 }
2368 const int index = length - enclosing_method_attribute_size;
2369 assert(offset < enclosing_method_attribute_size, "invalid offset");
2370 return inner_class_list->at(index + offset);
2371 }
2372
2373 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2374 u2 method_index) {
2375 Array<jushort>* inner_class_list = inner_classes();
2376 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2377 int length = inner_class_list->length();
2378 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2379 int index = length - enclosing_method_attribute_size;
2380 inner_class_list->at_put(
2381 index + enclosing_method_class_index_offset, class_index);
2382 inner_class_list->at_put(
2383 index + enclosing_method_method_index_offset, method_index);
2384 }
2385 }
2386
2387 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2388 if (method->is_old() && !method->is_obsolete()) {
2389 // If the method passed in is old (but not obsolete), use the current version.
2390 method = method_with_idnum((int)idnum);
2391 assert(method != nullptr, "old and but not obsolete, so should exist");
2392 }
2393 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2394 Atomic::release_store(&jmeths[idnum + 1], new_id);
2395 return new_id;
2396 }
2397
2398 // Lookup or create a jmethodID.
2399 // This code is called by the VMThread and JavaThreads so the
2400 // locking has to be done very carefully to avoid deadlocks
2401 // and/or other cache consistency problems.
2402 //
2403 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2404 Method* method = method_h();
2405 int idnum = method->method_idnum();
2406 jmethodID* jmeths = methods_jmethod_ids_acquire();
2407
2408 // We use a double-check locking idiom here because this cache is
2409 // performance sensitive. In the normal system, this cache only
2410 // transitions from null to non-null which is safe because we use
2411 // release_set_methods_jmethod_ids() to advertise the new cache.
2412 // A partially constructed cache should never be seen by a racing
2413 // thread. We also use release_store() to save a new jmethodID
2414 // in the cache so a partially constructed jmethodID should never be
2415 // seen either. Cache reads of existing jmethodIDs proceed without a
2416 // lock, but cache writes of a new jmethodID requires uniqueness and
2417 // creation of the cache itself requires no leaks so a lock is
2418 // acquired in those two cases.
2419 //
2420 // If the RedefineClasses() API has been used, then this cache grows
2421 // in the redefinition safepoint.
2422
2423 if (jmeths == nullptr) {
2424 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2425 jmeths = methods_jmethod_ids_acquire();
2426 // Still null?
2427 if (jmeths == nullptr) {
2428 size_t size = idnum_allocated_count();
2429 assert(size > (size_t)idnum, "should already have space");
2430 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2431 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2432 // cache size is stored in element[0], other elements offset by one
2433 jmeths[0] = (jmethodID)size;
2434 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2435
2436 // publish jmeths
2437 release_set_methods_jmethod_ids(jmeths);
2438 return new_id;
2439 }
2440 }
2441
2442 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2443 if (id == nullptr) {
2444 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2445 id = jmeths[idnum + 1];
2446 // Still null?
2447 if (id == nullptr) {
2448 return update_jmethod_id(jmeths, method, idnum);
2449 }
2450 }
2451 return id;
2452 }
2453
2454 void InstanceKlass::update_methods_jmethod_cache() {
2455 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2456 jmethodID* cache = _methods_jmethod_ids;
2457 if (cache != nullptr) {
2458 size_t size = idnum_allocated_count();
2459 size_t old_size = (size_t)cache[0];
2460 if (old_size < size + 1) {
2461 // Allocate a larger one and copy entries to the new one.
2462 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2463 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2464 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2465 // The cache size is stored in element[0]; the other elements are offset by one.
2466 new_cache[0] = (jmethodID)size;
2467
2468 for (int i = 1; i <= (int)old_size; i++) {
2469 new_cache[i] = cache[i];
2470 }
2471 _methods_jmethod_ids = new_cache;
2472 FREE_C_HEAP_ARRAY(jmethodID, cache);
2473 }
2474 }
2475 }
2476
2477 // Figure out how many jmethodIDs haven't been allocated, and make
2478 // sure space for them is pre-allocated. This makes getting all
2479 // method ids much, much faster with classes with more than 8
2480 // methods, and has a *substantial* effect on performance with jvmti
2481 // code that loads all jmethodIDs for all classes.
2482 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2483 int new_jmeths = 0;
2484 int length = methods()->length();
2485 for (int index = start_offset; index < length; index++) {
2486 Method* m = methods()->at(index);
2487 jmethodID id = m->find_jmethod_id_or_null();
2488 if (id == nullptr) {
2489 new_jmeths++;
2490 }
2491 }
2492 if (new_jmeths != 0) {
2493 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2494 }
2495 }
2496
2497 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2498 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2499 int idnum = method->method_idnum();
2500 jmethodID* jmeths = methods_jmethod_ids_acquire();
2501 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2502 }
2503
2504 inline DependencyContext InstanceKlass::dependencies() {
2505 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2506 return dep_context;
2507 }
2508
2509 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2510 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2511 }
2512
2513 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2514 assert_lock_strong(CodeCache_lock);
2515 dependencies().add_dependent_nmethod(nm);
2516 }
2517
2518 void InstanceKlass::clean_dependency_context() {
2519 dependencies().clean_unloading_dependents();
2520 }
2521
2522 #ifndef PRODUCT
2523 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2524 dependencies().print_dependent_nmethods(verbose);
2525 }
2526
2527 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2528 return dependencies().is_dependent_nmethod(nm);
2529 }
2530 #endif //PRODUCT
2531
2532 void InstanceKlass::clean_weak_instanceklass_links() {
2533 clean_implementors_list();
2534 clean_method_data();
2535 }
2536
2537 void InstanceKlass::clean_implementors_list() {
2538 assert(is_loader_alive(), "this klass should be live");
2539 if (is_interface()) {
2540 assert (ClassUnloading, "only called for ClassUnloading");
2541 for (;;) {
2542 // Use load_acquire due to competing with inserts
2543 InstanceKlass* volatile* iklass = adr_implementor();
2544 assert(iklass != nullptr, "Klass must not be null");
2545 InstanceKlass* impl = Atomic::load_acquire(iklass);
2546 if (impl != nullptr && !impl->is_loader_alive()) {
2547 // null this field, might be an unloaded instance klass or null
2548 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2549 // Successfully unlinking implementor.
2550 if (log_is_enabled(Trace, class, unload)) {
2551 ResourceMark rm;
2552 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2553 }
2554 return;
2555 }
2556 } else {
2557 return;
2558 }
2559 }
2560 }
2561 }
2562
2563 void InstanceKlass::clean_method_data() {
2564 for (int m = 0; m < methods()->length(); m++) {
2565 MethodData* mdo = methods()->at(m)->method_data();
2566 if (mdo != nullptr) {
2567 mdo->clean_method_data(/*always_clean*/false);
2568 }
2569 }
2570 }
2571
2572 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2573 Klass::metaspace_pointers_do(it);
2574
2575 if (log_is_enabled(Trace, aot)) {
2576 ResourceMark rm;
2577 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name());
2578 }
2579
2580 it->push(&_annotations);
2581 it->push((Klass**)&_array_klasses);
2582 if (!is_rewritten()) {
2583 it->push(&_constants, MetaspaceClosure::_writable);
2584 } else {
2585 it->push(&_constants);
2586 }
2587 it->push(&_inner_classes);
2588 #if INCLUDE_JVMTI
2589 it->push(&_previous_versions);
2590 #endif
2591 #if INCLUDE_CDS
2592 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2593 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2594 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2595 // The length check on the _methods is necessary because classes which don't have any
2596 // methods share the Universe::_the_empty_method_array which is in the RO region.
2597 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2598 // To handle jsr bytecode, new Method* maybe stored into _methods
2599 it->push(&_methods, MetaspaceClosure::_writable);
2600 } else {
2601 #endif
2602 it->push(&_methods);
2603 #if INCLUDE_CDS
2604 }
2605 #endif
2606 it->push(&_default_methods);
2607 it->push(&_local_interfaces);
2608 it->push(&_transitive_interfaces);
2609 it->push(&_method_ordering);
2610 if (!is_rewritten()) {
2611 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2612 } else {
2613 it->push(&_default_vtable_indices);
2614 }
2615
2616 it->push(&_fieldinfo_stream);
2617 it->push(&_fieldinfo_search_table);
2618 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2619 it->push(&_fields_status, MetaspaceClosure::_writable);
2620
2621 if (itable_length() > 0) {
2622 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2623 int method_table_offset_in_words = ioe->offset()/wordSize;
2624 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2625
2626 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2627 / itableOffsetEntry::size();
2628
2629 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2630 if (ioe->interface_klass() != nullptr) {
2631 it->push(ioe->interface_klass_addr());
2632 itableMethodEntry* ime = ioe->first_method_entry(this);
2633 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2634 for (int index = 0; index < n; index ++) {
2635 it->push(ime[index].method_addr());
2636 }
2637 }
2638 }
2639 }
2640
2641 it->push(&_nest_host);
2642 it->push(&_nest_members);
2643 it->push(&_permitted_subclasses);
2644 it->push(&_record_components);
2645 }
2646
2647 #if INCLUDE_CDS
2648 void InstanceKlass::remove_unshareable_info() {
2649
2650 if (is_linked()) {
2651 assert(can_be_verified_at_dumptime(), "must be");
2652 // Remember this so we can avoid walking the hierarchy at runtime.
2653 set_verified_at_dump_time();
2654 }
2655
2656 _misc_flags.set_has_init_deps_processed(false);
2657
2658 Klass::remove_unshareable_info();
2659
2660 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2661 // Classes are attempted to link during dumping and may fail,
2662 // but these classes are still in the dictionary and class list in CLD.
2663 // If the class has failed verification, there is nothing else to remove.
2664 return;
2665 }
2666
2667 // Reset to the 'allocated' state to prevent any premature accessing to
2668 // a shared class at runtime while the class is still being loaded and
2669 // restored. A class' init_state is set to 'loaded' at runtime when it's
2670 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2671 _init_state = allocated;
2672
2673 { // Otherwise this needs to take out the Compile_lock.
2674 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2675 init_implementor();
2676 }
2677
2678 // Call remove_unshareable_info() on other objects that belong to this class, except
2679 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2680 // ArchiveBuilder::make_klasses_shareable(),
2681
2682 for (int i = 0; i < methods()->length(); i++) {
2683 Method* m = methods()->at(i);
2684 m->remove_unshareable_info();
2685 }
2686
2687 // do array classes also.
2688 if (array_klasses() != nullptr) {
2689 array_klasses()->remove_unshareable_info();
2690 }
2691
2692 // These are not allocated from metaspace. They are safe to set to null.
2693 _source_debug_extension = nullptr;
2694 _dep_context = nullptr;
2695 _osr_nmethods_head = nullptr;
2696 #if INCLUDE_JVMTI
2697 _breakpoints = nullptr;
2698 _previous_versions = nullptr;
2699 _cached_class_file = nullptr;
2700 _jvmti_cached_class_field_map = nullptr;
2701 #endif
2702
2703 _init_thread = nullptr;
2704 _methods_jmethod_ids = nullptr;
2705 _jni_ids = nullptr;
2706 _oop_map_cache = nullptr;
2707 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) {
2708 // keep _nest_host
2709 } else {
2710 // clear _nest_host to ensure re-load at runtime
2711 _nest_host = nullptr;
2712 }
2713 init_shared_package_entry();
2714 _dep_context_last_cleaned = 0;
2715 DEBUG_ONLY(_shared_class_load_count = 0);
2716
2717 remove_unshareable_flags();
2718
2719 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2720 }
2721
2722 void InstanceKlass::remove_unshareable_flags() {
2723 // clear all the flags/stats that shouldn't be in the archived version
2724 assert(!is_scratch_class(), "must be");
2725 assert(!has_been_redefined(), "must be");
2726 #if INCLUDE_JVMTI
2727 set_is_being_redefined(false);
2728 #endif
2729 set_has_resolved_methods(false);
2730 }
2731
2732 void InstanceKlass::remove_java_mirror() {
2733 Klass::remove_java_mirror();
2734
2735 // do array classes also.
2736 if (array_klasses() != nullptr) {
2737 array_klasses()->remove_java_mirror();
2738 }
2739 }
2740
2741 void InstanceKlass::init_shared_package_entry() {
2742 assert(CDSConfig::is_dumping_archive(), "must be");
2743 #if !INCLUDE_CDS_JAVA_HEAP
2744 _package_entry = nullptr;
2745 #else
2746 if (CDSConfig::is_dumping_full_module_graph()) {
2747 if (defined_by_other_loaders()) {
2748 _package_entry = nullptr;
2749 } else {
2750 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2751 }
2752 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2753 CDSConfig::is_using_full_module_graph() &&
2754 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2755 // _package_entry is an archived package in the base archive. Leave it as is.
2756 } else {
2757 _package_entry = nullptr;
2758 }
2759 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2760 #endif
2761 }
2762
2763 void InstanceKlass::compute_has_loops_flag_for_methods() {
2764 Array<Method*>* methods = this->methods();
2765 for (int index = 0; index < methods->length(); ++index) {
2766 Method* m = methods->at(index);
2767 if (!m->is_overpass()) { // work around JDK-8305771
2768 m->compute_has_loops_flag();
2769 }
2770 }
2771 }
2772
2773 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2774 PackageEntry* pkg_entry, TRAPS) {
2775 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2776 // before the InstanceKlass is added to the SystemDictionary. Make
2777 // sure the current state is <loaded.
2778 assert(!is_loaded(), "invalid init state");
2779 assert(!shared_loading_failed(), "Must not try to load failed class again");
2780 set_package(loader_data, pkg_entry, CHECK);
2781 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2782
2783 Array<Method*>* methods = this->methods();
2784 int num_methods = methods->length();
2785 for (int index = 0; index < num_methods; ++index) {
2786 methods->at(index)->restore_unshareable_info(CHECK);
2787 }
2788 #if INCLUDE_JVMTI
2789 if (JvmtiExport::has_redefined_a_class()) {
2790 // Reinitialize vtable because RedefineClasses may have changed some
2791 // entries in this vtable for super classes so the CDS vtable might
2792 // point to old or obsolete entries. RedefineClasses doesn't fix up
2793 // vtables in the shared system dictionary, only the main one.
2794 // It also redefines the itable too so fix that too.
2795 // First fix any default methods that point to a super class that may
2796 // have been redefined.
2797 bool trace_name_printed = false;
2798 adjust_default_methods(&trace_name_printed);
2799 if (verified_at_dump_time()) {
2800 // Initialize vtable and itable for classes which can be verified at dump time.
2801 // Unlinked classes such as old classes with major version < 50 cannot be verified
2802 // at dump time.
2803 vtable().initialize_vtable();
2804 itable().initialize_itable();
2805 }
2806 }
2807 #endif // INCLUDE_JVMTI
2808
2809 // restore constant pool resolved references
2810 constants()->restore_unshareable_info(CHECK);
2811
2812 if (array_klasses() != nullptr) {
2813 // To get a consistent list of classes we need MultiArray_lock to ensure
2814 // array classes aren't observed while they are being restored.
2815 RecursiveLocker rl(MultiArray_lock, THREAD);
2816 assert(this == array_klasses()->bottom_klass(), "sanity");
2817 // Array classes have null protection domain.
2818 // --> see ArrayKlass::complete_create_array_klass()
2819 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2820 }
2821
2822 // Initialize @ValueBased class annotation if not already set in the archived klass.
2823 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2824 set_is_value_based();
2825 }
2826
2827 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table));
2828 }
2829
2830 // Check if a class or any of its supertypes has a version older than 50.
2831 // CDS will not perform verification of old classes during dump time because
2832 // without changing the old verifier, the verification constraint cannot be
2833 // retrieved during dump time.
2834 // Verification of archived old classes will be performed during run time.
2835 bool InstanceKlass::can_be_verified_at_dumptime() const {
2836 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2837 // This is a class that was dumped into the base archive, so we know
2838 // it was verified at dump time.
2839 return true;
2840 }
2841 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2842 return false;
2843 }
2844 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2845 return false;
2846 }
2847 Array<InstanceKlass*>* interfaces = local_interfaces();
2848 int len = interfaces->length();
2849 for (int i = 0; i < len; i++) {
2850 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2851 return false;
2852 }
2853 }
2854 return true;
2855 }
2856
2857 #endif // INCLUDE_CDS
2858
2859 #if INCLUDE_JVMTI
2860 static void clear_all_breakpoints(Method* m) {
2861 m->clear_all_breakpoints();
2862 }
2863 #endif
2864
2865 void InstanceKlass::unload_class(InstanceKlass* ik) {
2866
2867 if (ik->is_scratch_class()) {
2868 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2869 return;
2870 }
2871 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2872
2873 // Release dependencies.
2874 ik->dependencies().remove_all_dependents();
2875
2876 // notify the debugger
2877 if (JvmtiExport::should_post_class_unload()) {
2878 JvmtiExport::post_class_unload(ik);
2879 }
2880
2881 // notify ClassLoadingService of class unload
2882 ClassLoadingService::notify_class_unloaded(ik);
2883
2884 SystemDictionaryShared::handle_class_unloading(ik);
2885
2886 if (log_is_enabled(Info, class, unload)) {
2887 ResourceMark rm;
2888 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2889 }
2890
2891 Events::log_class_unloading(Thread::current(), ik);
2892
2893 #if INCLUDE_JFR
2894 assert(ik != nullptr, "invariant");
2895 EventClassUnload event;
2896 event.set_unloadedClass(ik);
2897 event.set_definingClassLoader(ik->class_loader_data());
2898 event.commit();
2899 #endif
2900 }
2901
2902 static void method_release_C_heap_structures(Method* m) {
2903 m->release_C_heap_structures();
2904 }
2905
2906 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2907 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2908 // Clean up C heap
2909 Klass::release_C_heap_structures();
2910
2911 // Deallocate and call destructors for MDO mutexes
2912 if (release_sub_metadata) {
2913 methods_do(method_release_C_heap_structures);
2914 }
2915
2916 // Deallocate oop map cache
2917 if (_oop_map_cache != nullptr) {
2918 delete _oop_map_cache;
2919 _oop_map_cache = nullptr;
2920 }
2921
2922 // Deallocate JNI identifiers for jfieldIDs
2923 JNIid::deallocate(jni_ids());
2924 set_jni_ids(nullptr);
2925
2926 jmethodID* jmeths = methods_jmethod_ids_acquire();
2927 if (jmeths != nullptr) {
2928 release_set_methods_jmethod_ids(nullptr);
2929 FreeHeap(jmeths);
2930 }
2931
2932 assert(_dep_context == nullptr,
2933 "dependencies should already be cleaned");
2934
2935 #if INCLUDE_JVMTI
2936 // Deallocate breakpoint records
2937 if (breakpoints() != nullptr) {
2938 methods_do(clear_all_breakpoints);
2939 assert(breakpoints() == nullptr, "should have cleared breakpoints");
2940 }
2941
2942 // deallocate the cached class file
2943 if (_cached_class_file != nullptr) {
2944 os::free(_cached_class_file);
2945 _cached_class_file = nullptr;
2946 }
2947 #endif
2948
2949 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2950
2951 if (release_sub_metadata) {
2952 constants()->release_C_heap_structures();
2953 }
2954 }
2955
2956 // The constant pool is on stack if any of the methods are executing or
2957 // referenced by handles.
2958 bool InstanceKlass::on_stack() const {
2959 return _constants->on_stack();
2960 }
2961
2962 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
2963 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
2964 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
2965
2966 // minor and major version numbers of class file
2967 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
2968 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
2969 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
2970 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
2971
2972 const InstanceKlass* InstanceKlass::get_klass_version(int version) const {
2973 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
2974 if (ik->constants()->version() == version) {
2975 return ik;
2976 }
2977 }
2978 return nullptr;
2979 }
2980
2981 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2982 if (array == nullptr) {
2983 _source_debug_extension = nullptr;
2984 } else {
2985 // Adding one to the attribute length in order to store a null terminator
2986 // character could cause an overflow because the attribute length is
2987 // already coded with an u4 in the classfile, but in practice, it's
2988 // unlikely to happen.
2989 assert((length+1) > length, "Overflow checking");
2990 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2991 for (int i = 0; i < length; i++) {
2992 sde[i] = array[i];
2993 }
2994 sde[length] = '\0';
2995 _source_debug_extension = sde;
2996 }
2997 }
2998
2999 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3000 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3001 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3002
3003 const char* InstanceKlass::signature_name() const {
3004
3005 // Get the internal name as a c string
3006 const char* src = (const char*) (name()->as_C_string());
3007 const int src_length = (int)strlen(src);
3008
3009 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3010
3011 // Add L as type indicator
3012 int dest_index = 0;
3013 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3014
3015 // Add the actual class name
3016 for (int src_index = 0; src_index < src_length; ) {
3017 dest[dest_index++] = src[src_index++];
3018 }
3019
3020 if (is_hidden()) { // Replace the last '+' with a '.'.
3021 for (int index = (int)src_length; index > 0; index--) {
3022 if (dest[index] == '+') {
3023 dest[index] = JVM_SIGNATURE_DOT;
3024 break;
3025 }
3026 }
3027 }
3028
3029 // Add the semicolon and the null
3030 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3031 dest[dest_index] = '\0';
3032 return dest;
3033 }
3034
3035 ModuleEntry* InstanceKlass::module() const {
3036 if (is_hidden() &&
3037 in_unnamed_package() &&
3038 class_loader_data()->has_class_mirror_holder()) {
3039 // For a non-strong hidden class defined to an unnamed package,
3040 // its (class held) CLD will not have an unnamed module created for it.
3041 // Two choices to find the correct ModuleEntry:
3042 // 1. If hidden class is within a nest, use nest host's module
3043 // 2. Find the unnamed module off from the class loader
3044 // For now option #2 is used since a nest host is not set until
3045 // after the instance class is created in jvm_lookup_define_class().
3046 if (class_loader_data()->is_boot_class_loader_data()) {
3047 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3048 } else {
3049 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3050 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3051 return java_lang_Module::module_entry(module);
3052 }
3053 }
3054
3055 // Class is in a named package
3056 if (!in_unnamed_package()) {
3057 return _package_entry->module();
3058 }
3059
3060 // Class is in an unnamed package, return its loader's unnamed module
3061 return class_loader_data()->unnamed_module();
3062 }
3063
3064 bool InstanceKlass::in_javabase_module() const {
3065 return module()->name() == vmSymbols::java_base();
3066 }
3067
3068 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3069
3070 // ensure java/ packages only loaded by boot or platform builtin loaders
3071 // not needed for shared class since CDS does not archive prohibited classes.
3072 if (!is_shared()) {
3073 check_prohibited_package(name(), loader_data, CHECK);
3074 }
3075
3076 if (is_shared() && _package_entry != nullptr) {
3077 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3078 // we can use the saved package
3079 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3080 return;
3081 } else {
3082 _package_entry = nullptr;
3083 }
3084 }
3085
3086 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3087 // it returns, so we need to decrement it when the current function exits.
3088 TempNewSymbol from_class_name =
3089 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3090
3091 Symbol* pkg_name;
3092 if (pkg_entry != nullptr) {
3093 pkg_name = pkg_entry->name();
3094 } else {
3095 pkg_name = from_class_name;
3096 }
3097
3098 if (pkg_name != nullptr && loader_data != nullptr) {
3099
3100 // Find in class loader's package entry table.
3101 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3102
3103 // If the package name is not found in the loader's package
3104 // entry table, it is an indication that the package has not
3105 // been defined. Consider it defined within the unnamed module.
3106 if (_package_entry == nullptr) {
3107
3108 if (!ModuleEntryTable::javabase_defined()) {
3109 // Before java.base is defined during bootstrapping, define all packages in
3110 // the java.base module. If a non-java.base package is erroneously placed
3111 // in the java.base module it will be caught later when java.base
3112 // is defined by ModuleEntryTable::verify_javabase_packages check.
3113 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3114 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3115 } else {
3116 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3117 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3118 }
3119
3120 // A package should have been successfully created
3121 DEBUG_ONLY(ResourceMark rm(THREAD));
3122 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3123 name()->as_C_string(), loader_data->loader_name_and_id());
3124 }
3125
3126 if (log_is_enabled(Debug, module)) {
3127 ResourceMark rm(THREAD);
3128 ModuleEntry* m = _package_entry->module();
3129 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3130 external_name(),
3131 pkg_name->as_C_string(),
3132 loader_data->loader_name_and_id(),
3133 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3134 }
3135 } else {
3136 ResourceMark rm(THREAD);
3137 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3138 external_name(),
3139 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3140 UNNAMED_MODULE);
3141 }
3142 }
3143
3144 // Function set_classpath_index ensures that for a non-null _package_entry
3145 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3146 // It then sets the classpath_index in the package entry record.
3147 //
3148 // The classpath_index field is used to find the entry on the boot loader class
3149 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3150 // in an unnamed module. It is also used to indicate (for all packages whose
3151 // classes are loaded by the boot loader) that at least one of the package's
3152 // classes has been loaded.
3153 void InstanceKlass::set_classpath_index(s2 path_index) {
3154 if (_package_entry != nullptr) {
3155 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3156 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3157 assert(path_index != -1, "Unexpected classpath_index");
3158 _package_entry->set_classpath_index(path_index);
3159 }
3160 }
3161
3162 // different versions of is_same_class_package
3163
3164 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3165 oop classloader1 = this->class_loader();
3166 PackageEntry* classpkg1 = this->package();
3167 if (class2->is_objArray_klass()) {
3168 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3169 }
3170
3171 oop classloader2;
3172 PackageEntry* classpkg2;
3173 if (class2->is_instance_klass()) {
3174 classloader2 = class2->class_loader();
3175 classpkg2 = class2->package();
3176 } else {
3177 assert(class2->is_typeArray_klass(), "should be type array");
3178 classloader2 = nullptr;
3179 classpkg2 = nullptr;
3180 }
3181
3182 // Same package is determined by comparing class loader
3183 // and package entries. Both must be the same. This rule
3184 // applies even to classes that are defined in the unnamed
3185 // package, they still must have the same class loader.
3186 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3187 return true;
3188 }
3189
3190 return false;
3191 }
3192
3193 // return true if this class and other_class are in the same package. Classloader
3194 // and classname information is enough to determine a class's package
3195 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3196 const Symbol* other_class_name) const {
3197 if (class_loader() != other_class_loader) {
3198 return false;
3199 }
3200 if (name()->fast_compare(other_class_name) == 0) {
3201 return true;
3202 }
3203
3204 {
3205 ResourceMark rm;
3206
3207 bool bad_class_name = false;
3208 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3209 if (bad_class_name) {
3210 return false;
3211 }
3212 // Check that package_from_class_name() returns null, not "", if there is no package.
3213 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3214
3215 const Symbol* const this_package_name =
3216 this->package() != nullptr ? this->package()->name() : nullptr;
3217
3218 if (this_package_name == nullptr || other_pkg == nullptr) {
3219 // One of the two doesn't have a package. Only return true if the other
3220 // one also doesn't have a package.
3221 return this_package_name == other_pkg;
3222 }
3223
3224 // Check if package is identical
3225 return this_package_name->fast_compare(other_pkg) == 0;
3226 }
3227 }
3228
3229 static bool is_prohibited_package_slow(Symbol* class_name) {
3230 // Caller has ResourceMark
3231 int length;
3232 jchar* unicode = class_name->as_unicode(length);
3233 return (length >= 5 &&
3234 unicode[0] == 'j' &&
3235 unicode[1] == 'a' &&
3236 unicode[2] == 'v' &&
3237 unicode[3] == 'a' &&
3238 unicode[4] == '/');
3239 }
3240
3241 // Only boot and platform class loaders can define classes in "java/" packages.
3242 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3243 ClassLoaderData* loader_data,
3244 TRAPS) {
3245 if (!loader_data->is_boot_class_loader_data() &&
3246 !loader_data->is_platform_class_loader_data() &&
3247 class_name != nullptr && class_name->utf8_length() >= 5) {
3248 ResourceMark rm(THREAD);
3249 bool prohibited;
3250 const u1* base = class_name->base();
3251 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3252 prohibited = is_prohibited_package_slow(class_name);
3253 } else {
3254 char* name = class_name->as_C_string();
3255 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3256 }
3257 if (prohibited) {
3258 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3259 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3260 char* name = pkg_name->as_C_string();
3261 const char* class_loader_name = loader_data->loader_name_and_id();
3262 StringUtils::replace_no_expand(name, "/", ".");
3263 const char* msg_text1 = "Class loader (instance of): ";
3264 const char* msg_text2 = " tried to load prohibited package name: ";
3265 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3266 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3267 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3268 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3269 }
3270 }
3271 return;
3272 }
3273
3274 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3275 constantPoolHandle i_cp(THREAD, constants());
3276 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3277 int ioff = iter.inner_class_info_index();
3278 if (ioff != 0) {
3279 // Check to see if the name matches the class we're looking for
3280 // before attempting to find the class.
3281 if (i_cp->klass_name_at_matches(this, ioff)) {
3282 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3283 if (this == inner_klass) {
3284 *ooff = iter.outer_class_info_index();
3285 *noff = iter.inner_name_index();
3286 return true;
3287 }
3288 }
3289 }
3290 }
3291 return false;
3292 }
3293
3294 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3295 InstanceKlass* outer_klass = nullptr;
3296 *inner_is_member = false;
3297 int ooff = 0, noff = 0;
3298 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3299 if (has_inner_classes_attr) {
3300 constantPoolHandle i_cp(THREAD, constants());
3301 if (ooff != 0) {
3302 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3303 if (!ok->is_instance_klass()) {
3304 // If the outer class is not an instance klass then it cannot have
3305 // declared any inner classes.
3306 ResourceMark rm(THREAD);
3307 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3308 Exceptions::fthrow(
3309 THREAD_AND_LOCATION,
3310 vmSymbols::java_lang_IncompatibleClassChangeError(),
3311 "%s and %s disagree on InnerClasses attribute",
3312 ok->external_name(),
3313 external_name());
3314 return nullptr;
3315 }
3316 outer_klass = InstanceKlass::cast(ok);
3317 *inner_is_member = true;
3318 }
3319 if (nullptr == outer_klass) {
3320 // It may be a local class; try for that.
3321 int encl_method_class_idx = enclosing_method_class_index();
3322 if (encl_method_class_idx != 0) {
3323 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3324 outer_klass = InstanceKlass::cast(ok);
3325 *inner_is_member = false;
3326 }
3327 }
3328 }
3329
3330 // If no inner class attribute found for this class.
3331 if (nullptr == outer_klass) return nullptr;
3332
3333 // Throws an exception if outer klass has not declared k as an inner klass
3334 // We need evidence that each klass knows about the other, or else
3335 // the system could allow a spoof of an inner class to gain access rights.
3336 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3337 return outer_klass;
3338 }
3339
3340 u2 InstanceKlass::compute_modifier_flags() const {
3341 u2 access = access_flags().as_unsigned_short();
3342
3343 // But check if it happens to be member class.
3344 InnerClassesIterator iter(this);
3345 for (; !iter.done(); iter.next()) {
3346 int ioff = iter.inner_class_info_index();
3347 // Inner class attribute can be zero, skip it.
3348 // Strange but true: JVM spec. allows null inner class refs.
3349 if (ioff == 0) continue;
3350
3351 // only look at classes that are already loaded
3352 // since we are looking for the flags for our self.
3353 Symbol* inner_name = constants()->klass_name_at(ioff);
3354 if (name() == inner_name) {
3355 // This is really a member class.
3356 access = iter.inner_access_flags();
3357 break;
3358 }
3359 }
3360 // Remember to strip ACC_SUPER bit
3361 return (access & (~JVM_ACC_SUPER));
3362 }
3363
3364 jint InstanceKlass::jvmti_class_status() const {
3365 jint result = 0;
3366
3367 if (is_linked()) {
3368 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3369 }
3370
3371 if (is_initialized()) {
3372 assert(is_linked(), "Class status is not consistent");
3373 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3374 }
3375 if (is_in_error_state()) {
3376 result |= JVMTI_CLASS_STATUS_ERROR;
3377 }
3378 return result;
3379 }
3380
3381 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3382 bool implements_interface; // initialized by method_at_itable_or_null
3383 Method* m = method_at_itable_or_null(holder, index,
3384 implements_interface); // out parameter
3385 if (m != nullptr) {
3386 assert(implements_interface, "sanity");
3387 return m;
3388 } else if (implements_interface) {
3389 // Throw AbstractMethodError since corresponding itable slot is empty.
3390 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3391 } else {
3392 // If the interface isn't implemented by the receiver class,
3393 // the VM should throw IncompatibleClassChangeError.
3394 ResourceMark rm(THREAD);
3395 stringStream ss;
3396 bool same_module = (module() == holder->module());
3397 ss.print("Receiver class %s does not implement "
3398 "the interface %s defining the method to be called "
3399 "(%s%s%s)",
3400 external_name(), holder->external_name(),
3401 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3402 (same_module) ? "" : "; ",
3403 (same_module) ? "" : holder->class_in_module_of_loader());
3404 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3405 }
3406 }
3407
3408 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3409 klassItable itable(this);
3410 for (int i = 0; i < itable.size_offset_table(); i++) {
3411 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3412 if (offset_entry->interface_klass() == holder) {
3413 implements_interface = true;
3414 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3415 Method* m = ime[index].method();
3416 return m;
3417 }
3418 }
3419 implements_interface = false;
3420 return nullptr; // offset entry not found
3421 }
3422
3423 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3424 assert(is_linked(), "required");
3425 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3426 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3427
3428 int vtable_index = Method::invalid_vtable_index;
3429 Symbol* name = intf_method->name();
3430 Symbol* signature = intf_method->signature();
3431
3432 // First check in default method array
3433 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3434 int index = find_method_index(default_methods(),
3435 name, signature,
3436 Klass::OverpassLookupMode::find,
3437 Klass::StaticLookupMode::find,
3438 Klass::PrivateLookupMode::find);
3439 if (index >= 0) {
3440 vtable_index = default_vtable_indices()->at(index);
3441 }
3442 }
3443 if (vtable_index == Method::invalid_vtable_index) {
3444 // get vtable_index for miranda methods
3445 klassVtable vt = vtable();
3446 vtable_index = vt.index_of_miranda(name, signature);
3447 }
3448 return vtable_index;
3449 }
3450
3451 #if INCLUDE_JVMTI
3452 // update default_methods for redefineclasses for methods that are
3453 // not yet in the vtable due to concurrent subclass define and superinterface
3454 // redefinition
3455 // Note: those in the vtable, should have been updated via adjust_method_entries
3456 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3457 // search the default_methods for uses of either obsolete or EMCP methods
3458 if (default_methods() != nullptr) {
3459 for (int index = 0; index < default_methods()->length(); index ++) {
3460 Method* old_method = default_methods()->at(index);
3461 if (old_method == nullptr || !old_method->is_old()) {
3462 continue; // skip uninteresting entries
3463 }
3464 assert(!old_method->is_deleted(), "default methods may not be deleted");
3465 Method* new_method = old_method->get_new_method();
3466 default_methods()->at_put(index, new_method);
3467
3468 if (log_is_enabled(Info, redefine, class, update)) {
3469 ResourceMark rm;
3470 if (!(*trace_name_printed)) {
3471 log_info(redefine, class, update)
3472 ("adjust: klassname=%s default methods from name=%s",
3473 external_name(), old_method->method_holder()->external_name());
3474 *trace_name_printed = true;
3475 }
3476 log_debug(redefine, class, update, vtables)
3477 ("default method update: %s(%s) ",
3478 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3479 }
3480 }
3481 }
3482 }
3483 #endif // INCLUDE_JVMTI
3484
3485 // On-stack replacement stuff
3486 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3487 assert_lock_strong(NMethodState_lock);
3488 #ifndef PRODUCT
3489 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3490 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3491 "redundant OSR recompilation detected. memory leak in CodeCache!");
3492 #endif
3493 // only one compilation can be active
3494 assert(n->is_osr_method(), "wrong kind of nmethod");
3495 n->set_osr_link(osr_nmethods_head());
3496 set_osr_nmethods_head(n);
3497 // Raise the highest osr level if necessary
3498 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3499
3500 // Get rid of the osr methods for the same bci that have lower levels.
3501 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3502 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3503 if (inv != nullptr && inv->is_in_use()) {
3504 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL);
3505 }
3506 }
3507 }
3508
3509 // Remove osr nmethod from the list. Return true if found and removed.
3510 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3511 // This is a short non-blocking critical region, so the no safepoint check is ok.
3512 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3513 assert(n->is_osr_method(), "wrong kind of nmethod");
3514 nmethod* last = nullptr;
3515 nmethod* cur = osr_nmethods_head();
3516 int max_level = CompLevel_none; // Find the max comp level excluding n
3517 Method* m = n->method();
3518 // Search for match
3519 bool found = false;
3520 while(cur != nullptr && cur != n) {
3521 if (m == cur->method()) {
3522 // Find max level before n
3523 max_level = MAX2(max_level, cur->comp_level());
3524 }
3525 last = cur;
3526 cur = cur->osr_link();
3527 }
3528 nmethod* next = nullptr;
3529 if (cur == n) {
3530 found = true;
3531 next = cur->osr_link();
3532 if (last == nullptr) {
3533 // Remove first element
3534 set_osr_nmethods_head(next);
3535 } else {
3536 last->set_osr_link(next);
3537 }
3538 }
3539 n->set_osr_link(nullptr);
3540 cur = next;
3541 while (cur != nullptr) {
3542 // Find max level after n
3543 if (m == cur->method()) {
3544 max_level = MAX2(max_level, cur->comp_level());
3545 }
3546 cur = cur->osr_link();
3547 }
3548 m->set_highest_osr_comp_level(max_level);
3549 return found;
3550 }
3551
3552 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3553 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3554 nmethod* osr = osr_nmethods_head();
3555 int found = 0;
3556 while (osr != nullptr) {
3557 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3558 if (osr->method() == m) {
3559 deopt_scope->mark(osr);
3560 found++;
3561 }
3562 osr = osr->osr_link();
3563 }
3564 return found;
3565 }
3566
3567 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3568 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3569 nmethod* osr = osr_nmethods_head();
3570 nmethod* best = nullptr;
3571 while (osr != nullptr) {
3572 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3573 // There can be a time when a c1 osr method exists but we are waiting
3574 // for a c2 version. When c2 completes its osr nmethod we will trash
3575 // the c1 version and only be able to find the c2 version. However
3576 // while we overflow in the c1 code at back branches we don't want to
3577 // try and switch to the same code as we are already running
3578
3579 if (osr->method() == m &&
3580 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3581 if (match_level) {
3582 if (osr->comp_level() == comp_level) {
3583 // Found a match - return it.
3584 return osr;
3585 }
3586 } else {
3587 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3588 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3589 // Found the best possible - return it.
3590 return osr;
3591 }
3592 best = osr;
3593 }
3594 }
3595 }
3596 osr = osr->osr_link();
3597 }
3598
3599 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3600 if (best != nullptr && best->comp_level() >= comp_level) {
3601 return best;
3602 }
3603 return nullptr;
3604 }
3605
3606 // -----------------------------------------------------------------------------------------------------
3607 // Printing
3608
3609 #define BULLET " - "
3610
3611 static const char* state_names[] = {
3612 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3613 };
3614
3615 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3616 for (int i = 0; i < len; i++) {
3617 intptr_t e = start[i];
3618 st->print("%d : " INTPTR_FORMAT, i, e);
3619 if (MetaspaceObj::is_valid((Metadata*)e)) {
3620 st->print(" ");
3621 ((Metadata*)e)->print_value_on(st);
3622 }
3623 st->cr();
3624 }
3625 }
3626
3627 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3628 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3629 }
3630
3631 const char* InstanceKlass::init_state_name() const {
3632 return state_names[init_state()];
3633 }
3634
3635 void InstanceKlass::print_on(outputStream* st) const {
3636 assert(is_klass(), "must be klass");
3637 Klass::print_on(st);
3638
3639 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3640 st->print(BULLET"klass size: %d", size()); st->cr();
3641 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3642 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3643 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3644 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3645 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3646 st->print(BULLET"sub: ");
3647 Klass* sub = subklass();
3648 int n;
3649 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3650 if (n < MaxSubklassPrintSize) {
3651 sub->print_value_on(st);
3652 st->print(" ");
3653 }
3654 }
3655 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3656 st->cr();
3657
3658 if (is_interface()) {
3659 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3660 if (nof_implementors() == 1) {
3661 st->print_cr(BULLET"implementor: ");
3662 st->print(" ");
3663 implementor()->print_value_on(st);
3664 st->cr();
3665 }
3666 }
3667
3668 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3669 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3670 if (Verbose || WizardMode) {
3671 Array<Method*>* method_array = methods();
3672 for (int i = 0; i < method_array->length(); i++) {
3673 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3674 }
3675 }
3676 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3677 if (default_methods() != nullptr) {
3678 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3679 if (Verbose) {
3680 Array<Method*>* method_array = default_methods();
3681 for (int i = 0; i < method_array->length(); i++) {
3682 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3683 }
3684 }
3685 }
3686 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3687 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3688 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3689
3690 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3691
3692 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3693 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3694
3695 if (secondary_supers() != nullptr) {
3696 if (Verbose) {
3697 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3698 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3699 for (int i = 0; i < _secondary_supers->length(); i++) {
3700 ResourceMark rm; // for external_name()
3701 Klass* secondary_super = _secondary_supers->at(i);
3702 st->print(BULLET"%2d:", i);
3703 if (is_hashed) {
3704 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3705 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3706 st->print(" dist:%02d:", distance);
3707 }
3708 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3709 }
3710 }
3711 }
3712 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3713
3714 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3715 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3716 if (source_debug_extension() != nullptr) {
3717 st->print(BULLET"source debug extension: ");
3718 st->print("%s", source_debug_extension());
3719 st->cr();
3720 }
3721 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3722 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3723 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3724 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3725 {
3726 bool have_pv = false;
3727 // previous versions are linked together through the InstanceKlass
3728 for (InstanceKlass* pv_node = previous_versions();
3729 pv_node != nullptr;
3730 pv_node = pv_node->previous_versions()) {
3731 if (!have_pv)
3732 st->print(BULLET"previous version: ");
3733 have_pv = true;
3734 pv_node->constants()->print_value_on(st);
3735 }
3736 if (have_pv) st->cr();
3737 }
3738
3739 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3740 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3741 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3742 print_on_maybe_null(st, BULLET"record components: ", record_components());
3743 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3744 if (java_mirror() != nullptr) {
3745 st->print(BULLET"java mirror: ");
3746 java_mirror()->print_value_on(st);
3747 st->cr();
3748 } else {
3749 st->print_cr(BULLET"java mirror: null");
3750 }
3751 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3752 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3753 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3754 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3755 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3756
3757 FieldPrinter print_static_field(st);
3758 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3759 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3760 FieldPrinter print_nonstatic_field(st);
3761 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3762 ik->print_nonstatic_fields(&print_nonstatic_field);
3763
3764 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count());
3765 OopMapBlock* map = start_of_nonstatic_oop_maps();
3766 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3767 while (map < end_map) {
3768 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3769 map++;
3770 }
3771 st->cr();
3772
3773 if (fieldinfo_search_table() != nullptr) {
3774 st->print_cr(BULLET"---- field info search table:");
3775 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table);
3776 }
3777 }
3778
3779 void InstanceKlass::print_value_on(outputStream* st) const {
3780 assert(is_klass(), "must be klass");
3781 if (Verbose || WizardMode) access_flags().print_on(st);
3782 name()->print_value_on(st);
3783 }
3784
3785 void FieldPrinter::do_field(fieldDescriptor* fd) {
3786 _st->print(BULLET);
3787 if (_obj == nullptr) {
3788 fd->print_on(_st);
3789 _st->cr();
3790 } else {
3791 fd->print_on_for(_st, _obj);
3792 _st->cr();
3793 }
3794 }
3795
3796
3797 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3798 Klass::oop_print_on(obj, st);
3799
3800 if (this == vmClasses::String_klass()) {
3801 typeArrayOop value = java_lang_String::value(obj);
3802 juint length = java_lang_String::length(obj);
3803 if (value != nullptr &&
3804 value->is_typeArray() &&
3805 length <= (juint) value->length()) {
3806 st->print(BULLET"string: ");
3807 java_lang_String::print(obj, st);
3808 st->cr();
3809 }
3810 }
3811
3812 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj));
3813 FieldPrinter print_field(st, obj);
3814 print_nonstatic_fields(&print_field);
3815
3816 if (this == vmClasses::Class_klass()) {
3817 st->print(BULLET"signature: ");
3818 java_lang_Class::print_signature(obj, st);
3819 st->cr();
3820 Klass* real_klass = java_lang_Class::as_Klass(obj);
3821 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3822 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3823 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3824 }
3825 } else if (this == vmClasses::MethodType_klass()) {
3826 st->print(BULLET"signature: ");
3827 java_lang_invoke_MethodType::print_signature(obj, st);
3828 st->cr();
3829 }
3830 }
3831
3832 #ifndef PRODUCT
3833
3834 bool InstanceKlass::verify_itable_index(int i) {
3835 int method_count = klassItable::method_count_for_interface(this);
3836 assert(i >= 0 && i < method_count, "index out of bounds");
3837 return true;
3838 }
3839
3840 #endif //PRODUCT
3841
3842 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3843 st->print("a ");
3844 name()->print_value_on(st);
3845 obj->print_address_on(st);
3846 if (this == vmClasses::String_klass()
3847 && java_lang_String::value(obj) != nullptr) {
3848 ResourceMark rm;
3849 int len = java_lang_String::length(obj);
3850 int plen = (len < 24 ? len : 12);
3851 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3852 st->print(" = \"%s\"", str);
3853 if (len > plen)
3854 st->print("...[%d]", len);
3855 } else if (this == vmClasses::Class_klass()) {
3856 Klass* k = java_lang_Class::as_Klass(obj);
3857 st->print(" = ");
3858 if (k != nullptr) {
3859 k->print_value_on(st);
3860 } else {
3861 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3862 st->print("%s", tname ? tname : "type?");
3863 }
3864 } else if (this == vmClasses::MethodType_klass()) {
3865 st->print(" = ");
3866 java_lang_invoke_MethodType::print_signature(obj, st);
3867 } else if (java_lang_boxing_object::is_instance(obj)) {
3868 st->print(" = ");
3869 java_lang_boxing_object::print(obj, st);
3870 } else if (this == vmClasses::LambdaForm_klass()) {
3871 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3872 if (vmentry != nullptr) {
3873 st->print(" => ");
3874 vmentry->print_value_on(st);
3875 }
3876 } else if (this == vmClasses::MemberName_klass()) {
3877 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3878 if (vmtarget != nullptr) {
3879 st->print(" = ");
3880 vmtarget->print_value_on(st);
3881 } else {
3882 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3883 oop name = java_lang_invoke_MemberName::name(obj);
3884 if (clazz != nullptr) {
3885 clazz->print_value_on(st);
3886 } else {
3887 st->print("null");
3888 }
3889 st->print(".");
3890 if (name != nullptr) {
3891 name->print_value_on(st);
3892 } else {
3893 st->print("null");
3894 }
3895 }
3896 }
3897 }
3898
3899 const char* InstanceKlass::internal_name() const {
3900 return external_name();
3901 }
3902
3903 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3904 const ModuleEntry* module_entry,
3905 const ClassFileStream* cfs) const {
3906
3907 if (ClassListWriter::is_enabled()) {
3908 ClassListWriter::write(this, cfs);
3909 }
3910
3911 print_class_load_helper(loader_data, module_entry, cfs);
3912 print_class_load_cause_logging();
3913 }
3914
3915 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3916 const ModuleEntry* module_entry,
3917 const ClassFileStream* cfs) const {
3918
3919 if (!log_is_enabled(Info, class, load)) {
3920 return;
3921 }
3922
3923 ResourceMark rm;
3924 LogMessage(class, load) msg;
3925 stringStream info_stream;
3926
3927 // Name and class hierarchy info
3928 info_stream.print("%s", external_name());
3929
3930 // Source
3931 if (cfs != nullptr) {
3932 if (cfs->source() != nullptr) {
3933 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3934 if (module_name != nullptr) {
3935 // When the boot loader created the stream, it didn't know the module name
3936 // yet. Let's format it now.
3937 if (cfs->from_boot_loader_modules_image()) {
3938 info_stream.print(" source: jrt:/%s", module_name);
3939 } else {
3940 info_stream.print(" source: %s", cfs->source());
3941 }
3942 } else {
3943 info_stream.print(" source: %s", cfs->source());
3944 }
3945 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3946 Thread* current = Thread::current();
3947 Klass* caller = current->is_Java_thread() ?
3948 JavaThread::cast(current)->security_get_caller_class(1):
3949 nullptr;
3950 // caller can be null, for example, during a JVMTI VM_Init hook
3951 if (caller != nullptr) {
3952 info_stream.print(" source: instance of %s", caller->external_name());
3953 } else {
3954 // source is unknown
3955 }
3956 } else {
3957 oop class_loader = loader_data->class_loader();
3958 info_stream.print(" source: %s", class_loader->klass()->external_name());
3959 }
3960 } else {
3961 assert(this->is_shared(), "must be");
3962 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3963 info_stream.print(" source: shared objects file (top)");
3964 } else {
3965 info_stream.print(" source: shared objects file");
3966 }
3967 }
3968
3969 msg.info("%s", info_stream.as_string());
3970
3971 if (log_is_enabled(Debug, class, load)) {
3972 stringStream debug_stream;
3973
3974 // Class hierarchy info
3975 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
3976 p2i(this), p2i(superklass()));
3977
3978 // Interfaces
3979 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
3980 debug_stream.print(" interfaces:");
3981 int length = local_interfaces()->length();
3982 for (int i = 0; i < length; i++) {
3983 debug_stream.print(" " PTR_FORMAT,
3984 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3985 }
3986 }
3987
3988 // Class loader
3989 debug_stream.print(" loader: [");
3990 loader_data->print_value_on(&debug_stream);
3991 debug_stream.print("]");
3992
3993 // Classfile checksum
3994 if (cfs) {
3995 debug_stream.print(" bytes: %d checksum: %08x",
3996 cfs->length(),
3997 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3998 cfs->length()));
3999 }
4000
4001 msg.debug("%s", debug_stream.as_string());
4002 }
4003 }
4004
4005 void InstanceKlass::print_class_load_cause_logging() const {
4006 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4007 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4008 JavaThread* current = JavaThread::current();
4009 ResourceMark rm(current);
4010 const char* name = external_name();
4011
4012 if (LogClassLoadingCauseFor == nullptr ||
4013 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4014 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4015 return;
4016 }
4017
4018 // Log Java stack first
4019 {
4020 LogMessage(class, load, cause) msg;
4021 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4022
4023 info_stream.print_cr("Java stack when loading %s:", name);
4024 current->print_stack_on(&info_stream);
4025 }
4026
4027 // Log native stack second
4028 if (log_cause_native) {
4029 // Log to string first so that lines can be indented
4030 stringStream stack_stream;
4031 char buf[O_BUFLEN];
4032 address lastpc = nullptr;
4033 NativeStackPrinter nsp(current);
4034 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4035 true /* print_source_info */, -1 /* max stack */);
4036
4037 LogMessage(class, load, cause, native) msg;
4038 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4039 info_stream.print_cr("Native stack when loading %s:", name);
4040
4041 // Print each native stack line to the log
4042 int size = (int) stack_stream.size();
4043 char* stack = stack_stream.as_string();
4044 char* stack_end = stack + size;
4045 char* line_start = stack;
4046 for (char* p = stack; p < stack_end; p++) {
4047 if (*p == '\n') {
4048 *p = '\0';
4049 info_stream.print_cr("\t%s", line_start);
4050 line_start = p + 1;
4051 }
4052 }
4053 if (line_start < stack_end) {
4054 info_stream.print_cr("\t%s", line_start);
4055 }
4056 }
4057 }
4058 }
4059
4060 // Verification
4061
4062 class VerifyFieldClosure: public BasicOopIterateClosure {
4063 protected:
4064 template <class T> void do_oop_work(T* p) {
4065 oop obj = RawAccess<>::oop_load(p);
4066 if (!oopDesc::is_oop_or_null(obj)) {
4067 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4068 Universe::print_on(tty);
4069 guarantee(false, "boom");
4070 }
4071 }
4072 public:
4073 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4074 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4075 };
4076
4077 void InstanceKlass::verify_on(outputStream* st) {
4078 #ifndef PRODUCT
4079 // Avoid redundant verifies, this really should be in product.
4080 if (_verify_count == Universe::verify_count()) return;
4081 _verify_count = Universe::verify_count();
4082 #endif
4083
4084 // Verify Klass
4085 Klass::verify_on(st);
4086
4087 // Verify that klass is present in ClassLoaderData
4088 guarantee(class_loader_data()->contains_klass(this),
4089 "this class isn't found in class loader data");
4090
4091 // Verify vtables
4092 if (is_linked()) {
4093 // $$$ This used to be done only for m/s collections. Doing it
4094 // always seemed a valid generalization. (DLD -- 6/00)
4095 vtable().verify(st);
4096 }
4097
4098 // Verify first subklass
4099 if (subklass() != nullptr) {
4100 guarantee(subklass()->is_klass(), "should be klass");
4101 }
4102
4103 // Verify siblings
4104 Klass* super = this->super();
4105 Klass* sib = next_sibling();
4106 if (sib != nullptr) {
4107 if (sib == this) {
4108 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4109 }
4110
4111 guarantee(sib->is_klass(), "should be klass");
4112 guarantee(sib->super() == super, "siblings should have same superklass");
4113 }
4114
4115 // Verify local interfaces
4116 if (local_interfaces()) {
4117 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4118 for (int j = 0; j < local_interfaces->length(); j++) {
4119 InstanceKlass* e = local_interfaces->at(j);
4120 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4121 }
4122 }
4123
4124 // Verify transitive interfaces
4125 if (transitive_interfaces() != nullptr) {
4126 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4127 for (int j = 0; j < transitive_interfaces->length(); j++) {
4128 InstanceKlass* e = transitive_interfaces->at(j);
4129 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4130 }
4131 }
4132
4133 // Verify methods
4134 if (methods() != nullptr) {
4135 Array<Method*>* methods = this->methods();
4136 for (int j = 0; j < methods->length(); j++) {
4137 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4138 }
4139 for (int j = 0; j < methods->length() - 1; j++) {
4140 Method* m1 = methods->at(j);
4141 Method* m2 = methods->at(j + 1);
4142 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4143 }
4144 }
4145
4146 // Verify method ordering
4147 if (method_ordering() != nullptr) {
4148 Array<int>* method_ordering = this->method_ordering();
4149 int length = method_ordering->length();
4150 if (JvmtiExport::can_maintain_original_method_order() ||
4151 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4152 guarantee(length == methods()->length(), "invalid method ordering length");
4153 jlong sum = 0;
4154 for (int j = 0; j < length; j++) {
4155 int original_index = method_ordering->at(j);
4156 guarantee(original_index >= 0, "invalid method ordering index");
4157 guarantee(original_index < length, "invalid method ordering index");
4158 sum += original_index;
4159 }
4160 // Verify sum of indices 0,1,...,length-1
4161 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4162 } else {
4163 guarantee(length == 0, "invalid method ordering length");
4164 }
4165 }
4166
4167 // Verify default methods
4168 if (default_methods() != nullptr) {
4169 Array<Method*>* methods = this->default_methods();
4170 for (int j = 0; j < methods->length(); j++) {
4171 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4172 }
4173 for (int j = 0; j < methods->length() - 1; j++) {
4174 Method* m1 = methods->at(j);
4175 Method* m2 = methods->at(j + 1);
4176 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4177 }
4178 }
4179
4180 // Verify JNI static field identifiers
4181 if (jni_ids() != nullptr) {
4182 jni_ids()->verify(this);
4183 }
4184
4185 // Verify other fields
4186 if (constants() != nullptr) {
4187 guarantee(constants()->is_constantPool(), "should be constant pool");
4188 }
4189 }
4190
4191 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4192 Klass::oop_verify_on(obj, st);
4193 VerifyFieldClosure blk;
4194 obj->oop_iterate(&blk);
4195 }
4196
4197
4198 // JNIid class for jfieldIDs only
4199 // Note to reviewers:
4200 // These JNI functions are just moved over to column 1 and not changed
4201 // in the compressed oops workspace.
4202 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4203 _holder = holder;
4204 _offset = offset;
4205 _next = next;
4206 DEBUG_ONLY(_is_static_field_id = false;)
4207 }
4208
4209
4210 JNIid* JNIid::find(int offset) {
4211 JNIid* current = this;
4212 while (current != nullptr) {
4213 if (current->offset() == offset) return current;
4214 current = current->next();
4215 }
4216 return nullptr;
4217 }
4218
4219 void JNIid::deallocate(JNIid* current) {
4220 while (current != nullptr) {
4221 JNIid* next = current->next();
4222 delete current;
4223 current = next;
4224 }
4225 }
4226
4227
4228 void JNIid::verify(Klass* holder) {
4229 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4230 int end_field_offset;
4231 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4232
4233 JNIid* current = this;
4234 while (current != nullptr) {
4235 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4236 #ifdef ASSERT
4237 int o = current->offset();
4238 if (current->is_static_field_id()) {
4239 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4240 }
4241 #endif
4242 current = current->next();
4243 }
4244 }
4245
4246 void InstanceKlass::set_init_state(ClassState state) {
4247 #ifdef ASSERT
4248 bool good_state = is_shared() ? (_init_state <= state)
4249 : (_init_state < state);
4250 assert(good_state || state == allocated, "illegal state transition");
4251 #endif
4252 assert(_init_thread == nullptr, "should be cleared before state change");
4253 Atomic::release_store(&_init_state, state);
4254 }
4255
4256 #if INCLUDE_JVMTI
4257
4258 // RedefineClasses() support for previous versions
4259
4260 // Globally, there is at least one previous version of a class to walk
4261 // during class unloading, which is saved because old methods in the class
4262 // are still running. Otherwise the previous version list is cleaned up.
4263 bool InstanceKlass::_should_clean_previous_versions = false;
4264
4265 // Returns true if there are previous versions of a class for class
4266 // unloading only. Also resets the flag to false. purge_previous_version
4267 // will set the flag to true if there are any left, i.e., if there's any
4268 // work to do for next time. This is to avoid the expensive code cache
4269 // walk in CLDG::clean_deallocate_lists().
4270 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4271 bool ret = _should_clean_previous_versions;
4272 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4273 ret ? "true" : "false");
4274 _should_clean_previous_versions = false;
4275 return ret;
4276 }
4277
4278 // This nulls out jmethodIDs for all methods in 'klass'
4279 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4280 // during class unloading.
4281 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4282 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4283 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4284 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4285 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4286 Array<Method*>* method_refs = klass->methods();
4287 for (int k = 0; k < method_refs->length(); k++) {
4288 Method* method = method_refs->at(k);
4289 if (method != nullptr && method->is_obsolete()) {
4290 method->clear_jmethod_id();
4291 }
4292 }
4293 }
4294
4295 // Purge previous versions before adding new previous versions of the class and
4296 // during class unloading.
4297 void InstanceKlass::purge_previous_version_list() {
4298 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4299 assert(has_been_redefined(), "Should only be called for main class");
4300
4301 // Quick exit.
4302 if (previous_versions() == nullptr) {
4303 return;
4304 }
4305
4306 // This klass has previous versions so see what we can cleanup
4307 // while it is safe to do so.
4308
4309 int deleted_count = 0; // leave debugging breadcrumbs
4310 int live_count = 0;
4311 ClassLoaderData* loader_data = class_loader_data();
4312 assert(loader_data != nullptr, "should never be null");
4313
4314 ResourceMark rm;
4315 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4316
4317 // previous versions are linked together through the InstanceKlass
4318 InstanceKlass* pv_node = previous_versions();
4319 InstanceKlass* last = this;
4320 int version = 0;
4321
4322 // check the previous versions list
4323 for (; pv_node != nullptr; ) {
4324
4325 ConstantPool* pvcp = pv_node->constants();
4326 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4327
4328 if (!pvcp->on_stack()) {
4329 // If the constant pool isn't on stack, none of the methods
4330 // are executing. Unlink this previous_version.
4331 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4332 // so will be deallocated during the next phase of class unloading.
4333 log_trace(redefine, class, iklass, purge)
4334 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4335 // Unlink from previous version list.
4336 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4337 InstanceKlass* next = pv_node->previous_versions();
4338 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4339 pv_node->link_previous_versions(nullptr); // point next to null
4340 last->link_previous_versions(next);
4341 // Delete this node directly. Nothing is referring to it and we don't
4342 // want it to increase the counter for metadata to delete in CLDG.
4343 MetadataFactory::free_metadata(loader_data, pv_node);
4344 pv_node = next;
4345 deleted_count++;
4346 version++;
4347 continue;
4348 } else {
4349 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4350 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4351 live_count++;
4352 if (pvcp->is_shared()) {
4353 // Shared previous versions can never be removed so no cleaning is needed.
4354 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4355 } else {
4356 // Previous version alive, set that clean is needed for next time.
4357 _should_clean_previous_versions = true;
4358 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4359 }
4360 }
4361
4362 // next previous version
4363 last = pv_node;
4364 pv_node = pv_node->previous_versions();
4365 version++;
4366 }
4367 log_trace(redefine, class, iklass, purge)
4368 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4369 }
4370
4371 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4372 int emcp_method_count) {
4373 int obsolete_method_count = old_methods->length() - emcp_method_count;
4374
4375 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4376 _previous_versions != nullptr) {
4377 // We have a mix of obsolete and EMCP methods so we have to
4378 // clear out any matching EMCP method entries the hard way.
4379 int local_count = 0;
4380 for (int i = 0; i < old_methods->length(); i++) {
4381 Method* old_method = old_methods->at(i);
4382 if (old_method->is_obsolete()) {
4383 // only obsolete methods are interesting
4384 Symbol* m_name = old_method->name();
4385 Symbol* m_signature = old_method->signature();
4386
4387 // previous versions are linked together through the InstanceKlass
4388 int j = 0;
4389 for (InstanceKlass* prev_version = _previous_versions;
4390 prev_version != nullptr;
4391 prev_version = prev_version->previous_versions(), j++) {
4392
4393 Array<Method*>* method_refs = prev_version->methods();
4394 for (int k = 0; k < method_refs->length(); k++) {
4395 Method* method = method_refs->at(k);
4396
4397 if (!method->is_obsolete() &&
4398 method->name() == m_name &&
4399 method->signature() == m_signature) {
4400 // The current RedefineClasses() call has made all EMCP
4401 // versions of this method obsolete so mark it as obsolete
4402 log_trace(redefine, class, iklass, add)
4403 ("%s(%s): flush obsolete method @%d in version @%d",
4404 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4405
4406 method->set_is_obsolete();
4407 break;
4408 }
4409 }
4410
4411 // The previous loop may not find a matching EMCP method, but
4412 // that doesn't mean that we can optimize and not go any
4413 // further back in the PreviousVersion generations. The EMCP
4414 // method for this generation could have already been made obsolete,
4415 // but there still may be an older EMCP method that has not
4416 // been made obsolete.
4417 }
4418
4419 if (++local_count >= obsolete_method_count) {
4420 // no more obsolete methods so bail out now
4421 break;
4422 }
4423 }
4424 }
4425 }
4426 }
4427
4428 // Save the scratch_class as the previous version if any of the methods are running.
4429 // The previous_versions are used to set breakpoints in EMCP methods and they are
4430 // also used to clean MethodData links to redefined methods that are no longer running.
4431 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4432 int emcp_method_count) {
4433 assert(Thread::current()->is_VM_thread(),
4434 "only VMThread can add previous versions");
4435
4436 ResourceMark rm;
4437 log_trace(redefine, class, iklass, add)
4438 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4439
4440 // Clean out old previous versions for this class
4441 purge_previous_version_list();
4442
4443 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4444 // a previous redefinition may be made obsolete by this redefinition.
4445 Array<Method*>* old_methods = scratch_class->methods();
4446 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4447
4448 // If the constant pool for this previous version of the class
4449 // is not marked as being on the stack, then none of the methods
4450 // in this previous version of the class are on the stack so
4451 // we don't need to add this as a previous version.
4452 ConstantPool* cp_ref = scratch_class->constants();
4453 if (!cp_ref->on_stack()) {
4454 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4455 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4456 return;
4457 }
4458
4459 // Add previous version if any methods are still running or if this is
4460 // a shared class which should never be removed.
4461 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4462 scratch_class->link_previous_versions(previous_versions());
4463 link_previous_versions(scratch_class);
4464 if (cp_ref->is_shared()) {
4465 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4466 } else {
4467 // We only set clean_previous_versions flag for processing during class
4468 // unloading for non-shared classes.
4469 _should_clean_previous_versions = true;
4470 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4471 }
4472 } // end add_previous_version()
4473
4474 #endif // INCLUDE_JVMTI
4475
4476 Method* InstanceKlass::method_with_idnum(int idnum) const {
4477 Method* m = nullptr;
4478 if (idnum < methods()->length()) {
4479 m = methods()->at(idnum);
4480 }
4481 if (m == nullptr || m->method_idnum() != idnum) {
4482 for (int index = 0; index < methods()->length(); ++index) {
4483 m = methods()->at(index);
4484 if (m->method_idnum() == idnum) {
4485 return m;
4486 }
4487 }
4488 // None found, return null for the caller to handle.
4489 return nullptr;
4490 }
4491 return m;
4492 }
4493
4494
4495 Method* InstanceKlass::method_with_orig_idnum(int idnum) const {
4496 if (idnum >= methods()->length()) {
4497 return nullptr;
4498 }
4499 Method* m = methods()->at(idnum);
4500 if (m != nullptr && m->orig_method_idnum() == idnum) {
4501 return m;
4502 }
4503 // Obsolete method idnum does not match the original idnum
4504 for (int index = 0; index < methods()->length(); ++index) {
4505 m = methods()->at(index);
4506 if (m->orig_method_idnum() == idnum) {
4507 return m;
4508 }
4509 }
4510 // None found, return null for the caller to handle.
4511 return nullptr;
4512 }
4513
4514
4515 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const {
4516 const InstanceKlass* holder = get_klass_version(version);
4517 if (holder == nullptr) {
4518 return nullptr; // The version of klass is gone, no method is found
4519 }
4520 return holder->method_with_orig_idnum(idnum);
4521 }
4522
4523 #if INCLUDE_JVMTI
4524 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4525 return _cached_class_file;
4526 }
4527
4528 jint InstanceKlass::get_cached_class_file_len() {
4529 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4530 }
4531
4532 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4533 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4534 }
4535 #endif
4536
4537 // Make a step iterating over the class hierarchy under the root class.
4538 // Skips subclasses if requested.
4539 void ClassHierarchyIterator::next() {
4540 assert(_current != nullptr, "required");
4541 if (_visit_subclasses && _current->subklass() != nullptr) {
4542 _current = _current->subklass();
4543 return; // visit next subclass
4544 }
4545 _visit_subclasses = true; // reset
4546 while (_current->next_sibling() == nullptr && _current != _root) {
4547 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4548 }
4549 if (_current == _root) {
4550 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4551 _current = nullptr;
4552 return;
4553 }
4554 _current = _current->next_sibling();
4555 return; // visit next sibling subclass
4556 }