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 "precompiled.hpp"
26 #include "cds/aotClassInitializer.hpp"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/cdsEnumKlass.hpp"
30 #include "cds/classListWriter.hpp"
31 #include "cds/heapShared.hpp"
32 #include "cds/metaspaceShared.hpp"
33 #include "classfile/classFileParser.hpp"
34 #include "classfile/classFileStream.hpp"
35 #include "classfile/classLoader.hpp"
36 #include "classfile/classLoaderData.inline.hpp"
37 #include "classfile/javaClasses.hpp"
38 #include "classfile/moduleEntry.hpp"
39 #include "classfile/systemDictionary.hpp"
40 #include "classfile/systemDictionaryShared.hpp"
41 #include "classfile/verifier.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "code/codeCache.hpp"
45 #include "code/dependencyContext.hpp"
46 #include "compiler/compilationPolicy.hpp"
47 #include "compiler/compileBroker.hpp"
48 #include "gc/shared/collectedHeap.inline.hpp"
49 #include "interpreter/bytecodeHistogram.hpp"
50 #include "interpreter/bytecodeStream.hpp"
51 #include "interpreter/oopMapCache.hpp"
52 #include "interpreter/rewriter.hpp"
53 #include "jvm.h"
54 #include "jvmtifiles/jvmti.h"
55 #include "logging/log.hpp"
56 #include "klass.inline.hpp"
57 #include "logging/logMessage.hpp"
58 #include "logging/logStream.hpp"
59 #include "memory/allocation.inline.hpp"
60 #include "memory/iterator.inline.hpp"
61 #include "memory/metadataFactory.hpp"
62 #include "memory/metaspaceClosure.hpp"
63 #include "memory/oopFactory.hpp"
64 #include "memory/resourceArea.hpp"
65 #include "memory/universe.hpp"
66 #include "oops/fieldStreams.inline.hpp"
67 #include "oops/constantPool.hpp"
68 #include "oops/instanceClassLoaderKlass.hpp"
69 #include "oops/instanceKlass.inline.hpp"
70 #include "oops/instanceMirrorKlass.hpp"
71 #include "oops/instanceOop.hpp"
72 #include "oops/instanceStackChunkKlass.hpp"
73 #include "oops/klass.inline.hpp"
74 #include "oops/method.hpp"
75 #include "oops/oop.inline.hpp"
76 #include "oops/recordComponent.hpp"
77 #include "oops/symbol.hpp"
78 #include "oops/trainingData.hpp"
79 #include "prims/jvmtiExport.hpp"
80 #include "prims/jvmtiRedefineClasses.hpp"
81 #include "prims/jvmtiThreadState.hpp"
82 #include "prims/methodComparator.hpp"
83 #include "runtime/arguments.hpp"
84 #include "runtime/deoptimization.hpp"
85 #include "runtime/atomic.hpp"
86 #include "runtime/fieldDescriptor.inline.hpp"
87 #include "runtime/handles.inline.hpp"
88 #include "runtime/javaCalls.hpp"
89 #include "runtime/javaThread.inline.hpp"
90 #include "runtime/mutexLocker.hpp"
91 #include "runtime/orderAccess.hpp"
92 #include "runtime/os.inline.hpp"
93 #include "runtime/reflection.hpp"
94 #include "runtime/runtimeUpcalls.hpp"
95 #include "runtime/synchronizer.hpp"
96 #include "runtime/threads.hpp"
97 #include "services/classLoadingService.hpp"
98 #include "services/finalizerService.hpp"
99 #include "services/threadService.hpp"
100 #include "utilities/dtrace.hpp"
101 #include "utilities/events.hpp"
102 #include "utilities/macros.hpp"
103 #include "utilities/nativeStackPrinter.hpp"
104 #include "utilities/pair.hpp"
105 #include "utilities/stringUtils.hpp"
106 #ifdef COMPILER1
107 #include "c1/c1_Compiler.hpp"
108 #endif
109 #if INCLUDE_JFR
110 #include "jfr/jfrEvents.hpp"
111 #endif
112
113 #ifdef DTRACE_ENABLED
114
115
116 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
117 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
118 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
119 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
120 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
121 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
122 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
123 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
124 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
125 { \
126 char* data = nullptr; \
127 int len = 0; \
128 Symbol* clss_name = name(); \
129 if (clss_name != nullptr) { \
130 data = (char*)clss_name->bytes(); \
131 len = clss_name->utf8_length(); \
132 } \
133 HOTSPOT_CLASS_INITIALIZATION_##type( \
134 data, len, (void*)class_loader(), thread_type); \
135 }
136
137 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
138 { \
139 char* data = nullptr; \
140 int len = 0; \
141 Symbol* clss_name = name(); \
142 if (clss_name != nullptr) { \
143 data = (char*)clss_name->bytes(); \
144 len = clss_name->utf8_length(); \
145 } \
146 HOTSPOT_CLASS_INITIALIZATION_##type( \
147 data, len, (void*)class_loader(), thread_type, wait); \
148 }
149
150 #else // ndef DTRACE_ENABLED
151
152 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
153 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
154
155 #endif // ndef DTRACE_ENABLED
156
157 bool InstanceKlass::_finalization_enabled = true;
158
159 static inline bool is_class_loader(const Symbol* class_name,
160 const ClassFileParser& parser) {
161 assert(class_name != nullptr, "invariant");
162
163 if (class_name == vmSymbols::java_lang_ClassLoader()) {
164 return true;
165 }
166
167 if (vmClasses::ClassLoader_klass_loaded()) {
168 const Klass* const super_klass = parser.super_klass();
169 if (super_klass != nullptr) {
170 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
171 return true;
172 }
173 }
174 }
175 return false;
176 }
177
178 static inline bool is_stack_chunk_class(const Symbol* class_name,
179 const ClassLoaderData* loader_data) {
180 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
181 loader_data->is_the_null_class_loader_data());
182 }
183
184 // private: called to verify that k is a static member of this nest.
185 // We know that k is an instance class in the same package and hence the
186 // same classloader.
187 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
188 assert(!is_hidden(), "unexpected hidden class");
189 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
190 if (log_is_enabled(Trace, class, nestmates)) {
191 ResourceMark rm(current);
192 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
193 k->external_name(), this->external_name());
194 }
195 return false;
196 }
197
198 if (log_is_enabled(Trace, class, nestmates)) {
199 ResourceMark rm(current);
200 log_trace(class, nestmates)("Checking nest membership of %s in %s",
201 k->external_name(), this->external_name());
202 }
203
204 // Check for the named class in _nest_members.
205 // We don't resolve, or load, any classes.
206 for (int i = 0; i < _nest_members->length(); i++) {
207 int cp_index = _nest_members->at(i);
208 Symbol* name = _constants->klass_name_at(cp_index);
209 if (name == k->name()) {
210 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
211 return true;
212 }
213 }
214 log_trace(class, nestmates)("- class is NOT a nest member!");
215 return false;
216 }
217
218 // Called to verify that k is a permitted subclass of this class.
219 // The incoming stringStream is used to format the messages for error logging and for the caller
220 // to use for exception throwing.
221 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const {
222 Thread* current = Thread::current();
223 assert(k != nullptr, "sanity check");
224 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
225 "unexpected empty _permitted_subclasses array");
226
227 if (log_is_enabled(Trace, class, sealed)) {
228 ResourceMark rm(current);
229 log_trace(class, sealed)("Checking for permitted subclass %s in %s",
230 k->external_name(), this->external_name());
231 }
232
233 // Check that the class and its super are in the same module.
234 if (k->module() != this->module()) {
235 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, "
236 "and sealed class %s is in module '%s' with loader %s",
237 k->external_name(),
238 k->module()->name_as_C_string(),
239 k->module()->loader_data()->loader_name_and_id(),
240 this->external_name(),
241 this->module()->name_as_C_string(),
242 this->module()->loader_data()->loader_name_and_id());
243 log_trace(class, sealed)(" - %s", ss.as_string());
244 return false;
245 }
246
247 if (!k->is_public() && !is_same_class_package(k)) {
248 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, "
249 "and sealed class %s is in package '%s' with classloader %s",
250 k->external_name(),
251 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed",
252 k->module()->loader_data()->loader_name_and_id(),
253 this->external_name(),
254 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed",
255 this->module()->loader_data()->loader_name_and_id());
256 log_trace(class, sealed)(" - %s", ss.as_string());
257 return false;
258 }
259
260 for (int i = 0; i < _permitted_subclasses->length(); i++) {
261 int cp_index = _permitted_subclasses->at(i);
262 Symbol* name = _constants->klass_name_at(cp_index);
263 if (name == k->name()) {
264 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
265 return true;
266 }
267 }
268
269 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s",
270 k->external_name(), this->external_name());
271 log_trace(class, sealed)(" - %s", ss.as_string());
272 return false;
273 }
274
275 // Return nest-host class, resolving, validating and saving it if needed.
276 // In cases where this is called from a thread that cannot do classloading
277 // (such as a native JIT thread) then we simply return null, which in turn
278 // causes the access check to return false. Such code will retry the access
279 // from a more suitable environment later. Otherwise the _nest_host is always
280 // set once this method returns.
281 // Any errors from nest-host resolution must be preserved so they can be queried
282 // from higher-level access checking code, and reported as part of access checking
283 // exceptions.
284 // VirtualMachineErrors are propagated with a null return.
285 // Under any conditions where the _nest_host can be set to non-null the resulting
286 // value of it and, if applicable, the nest host resolution/validation error,
287 // are idempotent.
288 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
289 InstanceKlass* nest_host_k = _nest_host;
290 if (nest_host_k != nullptr) {
291 return nest_host_k;
292 }
293
294 ResourceMark rm(THREAD);
295
296 // need to resolve and save our nest-host class.
297 if (_nest_host_index != 0) { // we have a real nest_host
298 // Before trying to resolve check if we're in a suitable context
299 bool can_resolve = THREAD->can_call_java();
300 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
301 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
302 this->external_name());
303 return nullptr; // sentinel to say "try again from a different context"
304 }
305
306 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
307 this->external_name(),
308 _constants->klass_name_at(_nest_host_index)->as_C_string());
309
310 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
311 if (HAS_PENDING_EXCEPTION) {
312 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
313 return nullptr; // propagate VMEs
314 }
315 stringStream ss;
316 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
317 ss.print("Nest host resolution of %s with host %s failed: ",
318 this->external_name(), target_host_class);
319 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
320 const char* msg = ss.as_string(true /* on C-heap */);
321 constantPoolHandle cph(THREAD, constants());
322 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
323 CLEAR_PENDING_EXCEPTION;
324
325 log_trace(class, nestmates)("%s", msg);
326 } else {
327 // A valid nest-host is an instance class in the current package that lists this
328 // class as a nest member. If any of these conditions are not met the class is
329 // its own nest-host.
330 const char* error = nullptr;
331
332 // JVMS 5.4.4 indicates package check comes first
333 if (is_same_class_package(k)) {
334 // Now check actual membership. We can't be a member if our "host" is
335 // not an instance class.
336 if (k->is_instance_klass()) {
337 nest_host_k = InstanceKlass::cast(k);
338 bool is_member = nest_host_k->has_nest_member(THREAD, this);
339 if (is_member) {
340 _nest_host = nest_host_k; // save resolved nest-host value
341
342 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
343 this->external_name(), k->external_name());
344 return nest_host_k;
345 } else {
346 error = "current type is not listed as a nest member";
347 }
348 } else {
349 error = "host is not an instance class";
350 }
351 } else {
352 error = "types are in different packages";
353 }
354
355 // something went wrong, so record what and log it
356 {
357 stringStream ss;
358 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
359 this->external_name(),
360 this->class_loader_data()->loader_name_and_id(),
361 k->external_name(),
362 k->class_loader_data()->loader_name_and_id(),
363 error);
364 const char* msg = ss.as_string(true /* on C-heap */);
365 constantPoolHandle cph(THREAD, constants());
366 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
367 log_trace(class, nestmates)("%s", msg);
368 }
369 }
370 } else {
371 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
372 this->external_name());
373 }
374
375 // Either not in an explicit nest, or else an error occurred, so
376 // the nest-host is set to `this`. Any thread that sees this assignment
377 // will also see any setting of nest_host_error(), if applicable.
378 return (_nest_host = this);
379 }
380
381 // Dynamic nest member support: set this class's nest host to the given class.
382 // This occurs as part of the class definition, as soon as the instanceKlass
383 // has been created and doesn't require further resolution. The code:
384 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
385 // results in:
386 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
387 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
388 // We also know the "host" is a valid nest-host in the same package so we can
389 // assert some of those facts.
390 void InstanceKlass::set_nest_host(InstanceKlass* host) {
391 assert(is_hidden(), "must be a hidden class");
392 assert(host != nullptr, "null nest host specified");
393 assert(_nest_host == nullptr, "current class has resolved nest-host");
394 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
395 nest_host_error());
396 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
397 (host->_nest_host == host), "proposed host is not a valid nest-host");
398 // Can't assert this as package is not set yet:
399 // assert(is_same_class_package(host), "proposed host is in wrong package");
400
401 if (log_is_enabled(Trace, class, nestmates)) {
402 ResourceMark rm;
403 const char* msg = "";
404 // a hidden class does not expect a statically defined nest-host
405 if (_nest_host_index > 0) {
406 msg = "(the NestHost attribute in the current class is ignored)";
407 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
408 msg = "(the NestMembers attribute in the current class is ignored)";
409 }
410 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
411 this->external_name(),
412 host->external_name(),
413 msg);
414 }
415 // set dynamic nest host
416 _nest_host = host;
417 // Record dependency to keep nest host from being unloaded before this class.
418 ClassLoaderData* this_key = class_loader_data();
419 assert(this_key != nullptr, "sanity");
420 this_key->record_dependency(host);
421 }
422
423 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
424 // or we are k's nest_host - all of which is covered by comparing the two
425 // resolved_nest_hosts.
426 // Any exceptions (i.e. VMEs) are propagated.
427 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
428
429 assert(this != k, "this should be handled by higher-level code");
430
431 // Per JVMS 5.4.4 we first resolve and validate the current class, then
432 // the target class k.
433
434 InstanceKlass* cur_host = nest_host(CHECK_false);
435 if (cur_host == nullptr) {
436 return false;
437 }
438
439 Klass* k_nest_host = k->nest_host(CHECK_false);
440 if (k_nest_host == nullptr) {
441 return false;
442 }
443
444 bool access = (cur_host == k_nest_host);
445
446 ResourceMark rm(THREAD);
447 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
448 this->external_name(),
449 access ? "" : "NOT ",
450 k->external_name());
451 return access;
452 }
453
454 const char* InstanceKlass::nest_host_error() {
455 if (_nest_host_index == 0) {
456 return nullptr;
457 } else {
458 constantPoolHandle cph(Thread::current(), constants());
459 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
460 }
461 }
462
463 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
464 bool use_class_space, TRAPS) throw() {
465 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
466 }
467
468 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
469 const int size = InstanceKlass::size(parser.vtable_size(),
470 parser.itable_size(),
471 nonstatic_oop_map_size(parser.total_oop_map_count()),
472 parser.is_interface());
473
474 const Symbol* const class_name = parser.class_name();
475 assert(class_name != nullptr, "invariant");
476 ClassLoaderData* loader_data = parser.loader_data();
477 assert(loader_data != nullptr, "invariant");
478
479 InstanceKlass* ik;
480 const bool use_class_space = parser.klass_needs_narrow_id();
481
482 // Allocation
483 if (parser.is_instance_ref_klass()) {
484 // java.lang.ref.Reference
485 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
486 } else if (class_name == vmSymbols::java_lang_Class()) {
487 // mirror - java.lang.Class
488 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
489 } else if (is_stack_chunk_class(class_name, loader_data)) {
490 // stack chunk
491 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
492 } else if (is_class_loader(class_name, parser)) {
493 // class loader - java.lang.ClassLoader
494 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
495 } else {
496 // normal
497 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
498 }
499
500 if (ik != nullptr && UseCompressedClassPointers && use_class_space) {
501 assert(CompressedKlassPointers::is_encodable(ik),
502 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik));
503 }
504
505 // Check for pending exception before adding to the loader data and incrementing
506 // class count. Can get OOM here.
507 if (HAS_PENDING_EXCEPTION) {
508 return nullptr;
509 }
510
511 return ik;
512 }
513
514
515 // copy method ordering from resource area to Metaspace
516 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
517 if (m != nullptr) {
518 // allocate a new array and copy contents (memcpy?)
519 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
520 for (int i = 0; i < m->length(); i++) {
521 _method_ordering->at_put(i, m->at(i));
522 }
523 } else {
524 _method_ordering = Universe::the_empty_int_array();
525 }
526 }
527
528 // create a new array of vtable_indices for default methods
529 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
530 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
531 assert(default_vtable_indices() == nullptr, "only create once");
532 set_default_vtable_indices(vtable_indices);
533 return vtable_indices;
534 }
535
536
537 InstanceKlass::InstanceKlass() {
538 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
539 }
540
541 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
542 Klass(kind),
543 _nest_members(nullptr),
544 _nest_host(nullptr),
545 _permitted_subclasses(nullptr),
546 _record_components(nullptr),
547 _static_field_size(parser.static_field_size()),
548 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
549 _itable_len(parser.itable_size()),
550 _nest_host_index(0),
551 _init_state(allocated),
552 _reference_type(reference_type),
553 _init_thread(nullptr)
554 {
555 set_vtable_length(parser.vtable_size());
556 set_access_flags(parser.access_flags());
557 if (parser.is_hidden()) set_is_hidden();
558 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
559 false));
560
561 assert(nullptr == _methods, "underlying memory not zeroed?");
562 assert(is_instance_klass(), "is layout incorrect?");
563 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
564 }
565
566 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
567 Array<Method*>* methods) {
568 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
569 !methods->is_shared()) {
570 for (int i = 0; i < methods->length(); i++) {
571 Method* method = methods->at(i);
572 if (method == nullptr) continue; // maybe null if error processing
573 // Only want to delete methods that are not executing for RedefineClasses.
574 // The previous version will point to them so they're not totally dangling
575 assert (!method->on_stack(), "shouldn't be called with methods on stack");
576 MetadataFactory::free_metadata(loader_data, method);
577 }
578 MetadataFactory::free_array<Method*>(loader_data, methods);
579 }
580 }
581
582 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
583 const Klass* super_klass,
584 Array<InstanceKlass*>* local_interfaces,
585 Array<InstanceKlass*>* transitive_interfaces) {
586 // Only deallocate transitive interfaces if not empty, same as super class
587 // or same as local interfaces. See code in parseClassFile.
588 Array<InstanceKlass*>* ti = transitive_interfaces;
589 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
590 // check that the interfaces don't come from super class
591 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
592 InstanceKlass::cast(super_klass)->transitive_interfaces();
593 if (ti != sti && ti != nullptr && !ti->is_shared()) {
594 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
595 }
596 }
597
598 // local interfaces can be empty
599 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
600 local_interfaces != nullptr && !local_interfaces->is_shared()) {
601 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
602 }
603 }
604
605 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
606 Array<RecordComponent*>* record_components) {
607 if (record_components != nullptr && !record_components->is_shared()) {
608 for (int i = 0; i < record_components->length(); i++) {
609 RecordComponent* record_component = record_components->at(i);
610 MetadataFactory::free_metadata(loader_data, record_component);
611 }
612 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
613 }
614 }
615
616 // This function deallocates the metadata and C heap pointers that the
617 // InstanceKlass points to.
618 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
619 // Orphan the mirror first, CMS thinks it's still live.
620 if (java_mirror() != nullptr) {
621 java_lang_Class::set_klass(java_mirror(), nullptr);
622 }
623
624 // Also remove mirror from handles
625 loader_data->remove_handle(_java_mirror);
626
627 // Need to take this class off the class loader data list.
628 loader_data->remove_class(this);
629
630 // The array_klass for this class is created later, after error handling.
631 // For class redefinition, we keep the original class so this scratch class
632 // doesn't have an array class. Either way, assert that there is nothing
633 // to deallocate.
634 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
635
636 // Release C heap allocated data that this points to, which includes
637 // reference counting symbol names.
638 // Can't release the constant pool or MethodData C heap data here because the constant
639 // pool can be deallocated separately from the InstanceKlass for default methods and
640 // redefine classes. MethodData can also be released separately.
641 release_C_heap_structures(/* release_sub_metadata */ false);
642
643 deallocate_methods(loader_data, methods());
644 set_methods(nullptr);
645
646 deallocate_record_components(loader_data, record_components());
647 set_record_components(nullptr);
648
649 if (method_ordering() != nullptr &&
650 method_ordering() != Universe::the_empty_int_array() &&
651 !method_ordering()->is_shared()) {
652 MetadataFactory::free_array<int>(loader_data, method_ordering());
653 }
654 set_method_ordering(nullptr);
655
656 // default methods can be empty
657 if (default_methods() != nullptr &&
658 default_methods() != Universe::the_empty_method_array() &&
659 !default_methods()->is_shared()) {
660 MetadataFactory::free_array<Method*>(loader_data, default_methods());
661 }
662 // Do NOT deallocate the default methods, they are owned by superinterfaces.
663 set_default_methods(nullptr);
664
665 // default methods vtable indices can be empty
666 if (default_vtable_indices() != nullptr &&
667 !default_vtable_indices()->is_shared()) {
668 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
669 }
670 set_default_vtable_indices(nullptr);
671
672
673 // This array is in Klass, but remove it with the InstanceKlass since
674 // this place would be the only caller and it can share memory with transitive
675 // interfaces.
676 if (secondary_supers() != nullptr &&
677 secondary_supers() != Universe::the_empty_klass_array() &&
678 // see comments in compute_secondary_supers about the following cast
679 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
680 !secondary_supers()->is_shared()) {
681 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
682 }
683 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
684
685 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
686 set_transitive_interfaces(nullptr);
687 set_local_interfaces(nullptr);
688
689 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
690 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
691 }
692 set_fieldinfo_stream(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 (log_is_enabled(Info, cds, init)) {
869 ResourceMark rm;
870 log_info(cds, init)("%s (aot-inited)", external_name());
871 }
872
873 link_class(CHECK);
874
875 #ifdef ASSERT
876 {
877 Handle h_init_lock(THREAD, init_lock());
878 ObjectLocker ol(h_init_lock, THREAD);
879 assert(!is_initialized(), "sanity");
880 assert(!is_being_initialized(), "sanity");
881 assert(!is_in_error_state(), "sanity");
882 }
883 #endif
884
885 set_init_thread(THREAD);
886 set_initialization_state_and_notify(fully_initialized, CHECK);
887 AOTClassInitializer::call_runtime_setup(THREAD, this);
888 }
889 #endif
890
891 bool InstanceKlass::verify_code(TRAPS) {
892 // 1) Verify the bytecodes
893 return Verifier::verify(this, should_verify_class(), THREAD);
894 }
895
896 void InstanceKlass::link_class(TRAPS) {
897 assert(is_loaded(), "must be loaded");
898 if (!is_linked()) {
899 link_class_impl(CHECK);
900 }
901 }
902
903 // Called to verify that a class can link during initialization, without
904 // throwing a VerifyError.
905 bool InstanceKlass::link_class_or_fail(TRAPS) {
906 assert(is_loaded(), "must be loaded");
907 if (!is_linked()) {
908 link_class_impl(CHECK_false);
909 }
910 return is_linked();
911 }
912
913 bool InstanceKlass::link_class_impl(TRAPS) {
914 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
915 // This is for CDS static dump only -- we use the in_error_state to indicate that
916 // the class has failed verification. Throwing the NoClassDefFoundError here is just
917 // a convenient way to stop repeat attempts to verify the same (bad) class.
918 //
919 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
920 // if we are executing Java code. This is not a problem for CDS dumping phase since
921 // it doesn't execute any Java code.
922 ResourceMark rm(THREAD);
923 // Names are all known to be < 64k so we know this formatted message is not excessively large.
924 Exceptions::fthrow(THREAD_AND_LOCATION,
925 vmSymbols::java_lang_NoClassDefFoundError(),
926 "Class %s, or one of its supertypes, failed class initialization",
927 external_name());
928 return false;
929 }
930 // return if already verified
931 if (is_linked()) {
932 return true;
933 }
934
935 // Timing
936 // timer handles recursion
937 JavaThread* jt = THREAD;
938
939 // link super class before linking this class
940 Klass* super_klass = super();
941 if (super_klass != nullptr) {
942 if (super_klass->is_interface()) { // check if super class is an interface
943 ResourceMark rm(THREAD);
944 // Names are all known to be < 64k so we know this formatted message is not excessively large.
945 Exceptions::fthrow(
946 THREAD_AND_LOCATION,
947 vmSymbols::java_lang_IncompatibleClassChangeError(),
948 "class %s has interface %s as super class",
949 external_name(),
950 super_klass->external_name()
951 );
952 return false;
953 }
954
955 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
956 ik_super->link_class_impl(CHECK_false);
957 }
958
959 // link all interfaces implemented by this class before linking this class
960 Array<InstanceKlass*>* interfaces = local_interfaces();
961 int num_interfaces = interfaces->length();
962 for (int index = 0; index < num_interfaces; index++) {
963 InstanceKlass* interk = interfaces->at(index);
964 interk->link_class_impl(CHECK_false);
965 }
966
967 // in case the class is linked in the process of linking its superclasses
968 if (is_linked()) {
969 return true;
970 }
971
972 // trace only the link time for this klass that includes
973 // the verification time
974 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
975 ClassLoader::perf_class_link_selftime(),
976 ClassLoader::perf_classes_linked(),
977 jt->get_thread_stat()->perf_recursion_counts_addr(),
978 jt->get_thread_stat()->perf_timers_addr(),
979 PerfClassTraceTime::CLASS_LINK);
980
981 // verification & rewriting
982 {
983 HandleMark hm(THREAD);
984 Handle h_init_lock(THREAD, init_lock());
985 ObjectLocker ol(h_init_lock, jt);
986 // rewritten will have been set if loader constraint error found
987 // on an earlier link attempt
988 // don't verify or rewrite if already rewritten
989 //
990
991 if (!is_linked()) {
992 if (!is_rewritten()) {
993 if (is_shared()) {
994 assert(!verified_at_dump_time(), "must be");
995 }
996 {
997 bool verify_ok = verify_code(THREAD);
998 if (!verify_ok) {
999 return false;
1000 }
1001 }
1002
1003 // Just in case a side-effect of verify linked this class already
1004 // (which can sometimes happen since the verifier loads classes
1005 // using custom class loaders, which are free to initialize things)
1006 if (is_linked()) {
1007 return true;
1008 }
1009
1010 // also sets rewritten
1011 rewrite_class(CHECK_false);
1012 } else if (is_shared()) {
1013 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1014 }
1015
1016 // relocate jsrs and link methods after they are all rewritten
1017 link_methods(CHECK_false);
1018
1019 // Initialize the vtable and interface table after
1020 // methods have been rewritten since rewrite may
1021 // fabricate new Method*s.
1022 // also does loader constraint checking
1023 //
1024 // initialize_vtable and initialize_itable need to be rerun
1025 // for a shared class if
1026 // 1) the class is loaded by custom class loader or
1027 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1028 // 3) the class was not verified during dump time
1029 bool need_init_table = true;
1030 if (is_shared() && verified_at_dump_time() &&
1031 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1032 need_init_table = false;
1033 }
1034 if (need_init_table) {
1035 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1036 itable().initialize_itable_and_check_constraints(CHECK_false);
1037 }
1038 #ifdef ASSERT
1039 vtable().verify(tty, true);
1040 // In case itable verification is ever added.
1041 // itable().verify(tty, true);
1042 #endif
1043 if (Universe::is_fully_initialized()) {
1044 DeoptimizationScope deopt_scope;
1045 {
1046 // Now mark all code that assumes the class is not linked.
1047 // Set state under the Compile_lock also.
1048 MutexLocker ml(THREAD, Compile_lock);
1049
1050 set_init_state(linked);
1051 CodeCache::mark_dependents_on(&deopt_scope, this);
1052 }
1053 // Perform the deopt handshake outside Compile_lock.
1054 deopt_scope.deoptimize_marked();
1055 } else {
1056 set_init_state(linked);
1057 }
1058 if (JvmtiExport::should_post_class_prepare()) {
1059 JvmtiExport::post_class_prepare(THREAD, this);
1060 }
1061 }
1062 }
1063 return true;
1064 }
1065
1066 // Rewrite the byte codes of all of the methods of a class.
1067 // The rewriter must be called exactly once. Rewriting must happen after
1068 // verification but before the first method of the class is executed.
1069 void InstanceKlass::rewrite_class(TRAPS) {
1070 assert(is_loaded(), "must be loaded");
1071 if (is_rewritten()) {
1072 assert(is_shared(), "rewriting an unshared class?");
1073 return;
1074 }
1075 Rewriter::rewrite(this, CHECK);
1076 set_rewritten();
1077 }
1078
1079 // Now relocate and link method entry points after class is rewritten.
1080 // This is outside is_rewritten flag. In case of an exception, it can be
1081 // executed more than once.
1082 void InstanceKlass::link_methods(TRAPS) {
1083 PerfTraceElapsedTime timer(ClassLoader::perf_ik_link_methods_time());
1084
1085 int len = methods()->length();
1086 for (int i = len-1; i >= 0; i--) {
1087 methodHandle m(THREAD, methods()->at(i));
1088 RuntimeUpcalls::install_upcalls(m);
1089
1090 // Set up method entry points for compiler and interpreter .
1091 m->link_method(m, CHECK);
1092 }
1093 }
1094
1095 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1096 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1097 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1098 for (int i = 0; i < local_interfaces()->length(); ++i) {
1099 InstanceKlass* ik = local_interfaces()->at(i);
1100
1101 // Initialization is depth first search ie. we start with top of the inheritance tree
1102 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1103 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1104 if (ik->has_nonstatic_concrete_methods()) {
1105 ik->initialize_super_interfaces(CHECK);
1106 }
1107
1108 // Only initialize() interfaces that "declare" concrete methods.
1109 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1110 ik->initialize(CHECK);
1111 }
1112 }
1113 }
1114
1115 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1116 static InitializationErrorTable* _initialization_error_table;
1117
1118 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1119 // Create the same exception with a message indicating the thread name,
1120 // and the StackTraceElements.
1121 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1122 ResourceMark rm(current);
1123 if (init_error.is_null()) {
1124 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1125
1126 // We failed to create the new exception, most likely due to either out-of-memory or
1127 // a stackoverflow error. If the original exception was either of those then we save
1128 // the shared, pre-allocated, stackless, instance of that exception.
1129 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1130 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1131 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1132 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1133 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1134 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1135 } else {
1136 return;
1137 }
1138 }
1139
1140 MutexLocker ml(current, ClassInitError_lock);
1141 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1142 bool created;
1143 if (_initialization_error_table == nullptr) {
1144 _initialization_error_table = new (mtClass) InitializationErrorTable();
1145 }
1146 _initialization_error_table->put_if_absent(this, elem, &created);
1147 assert(created, "Initialization is single threaded");
1148 log_trace(class, init)("Initialization error added for class %s", external_name());
1149 }
1150
1151 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1152 MutexLocker ml(current, ClassInitError_lock);
1153 if (_initialization_error_table == nullptr) {
1154 return nullptr;
1155 }
1156 OopHandle* h = _initialization_error_table->get(this);
1157 return (h != nullptr) ? h->resolve() : nullptr;
1158 }
1159
1160 // Need to remove entries for unloaded classes.
1161 void InstanceKlass::clean_initialization_error_table() {
1162 struct InitErrorTableCleaner {
1163 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1164 if (!ik->is_loader_alive()) {
1165 h.release(Universe::vm_global());
1166 return true;
1167 } else {
1168 return false;
1169 }
1170 }
1171 };
1172
1173 assert_locked_or_safepoint(ClassInitError_lock);
1174 InitErrorTableCleaner cleaner;
1175 if (_initialization_error_table != nullptr) {
1176 _initialization_error_table->unlink(&cleaner);
1177 }
1178 }
1179
1180 void InstanceKlass::initialize_impl(TRAPS) {
1181 HandleMark hm(THREAD);
1182
1183 // Make sure klass is linked (verified) before initialization
1184 // A class could already be verified, since it has been reflected upon.
1185 link_class(CHECK);
1186
1187 DTRACE_CLASSINIT_PROBE(required, -1);
1188
1189 bool wait = false;
1190
1191 JavaThread* jt = THREAD;
1192
1193 if (ForceProfiling) {
1194 // Preallocate MDOs.
1195 for (int i = 0; i < methods()->length(); i++) {
1196 assert(!HAS_PENDING_EXCEPTION, "");
1197 methodHandle m(THREAD, methods()->at(i));
1198 Method::build_profiling_method_data(m, THREAD);
1199 if (HAS_PENDING_EXCEPTION) {
1200 ResourceMark rm;
1201 log_warning(cds)("MDO preallocation failed for %s", external_name());
1202 CLEAR_PENDING_EXCEPTION;
1203 break;
1204 }
1205 }
1206 }
1207
1208 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1209
1210 // refer to the JVM book page 47 for description of steps
1211 // Step 1
1212 {
1213 Handle h_init_lock(THREAD, init_lock());
1214 ObjectLocker ol(h_init_lock, jt);
1215
1216 // Step 2
1217 // If we were to use wait() instead of waitInterruptibly() then
1218 // we might end up throwing IE from link/symbol resolution sites
1219 // that aren't expected to throw. This would wreak havoc. See 6320309.
1220 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1221 if (debug_logging_enabled) {
1222 ResourceMark rm(jt);
1223 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1224 jt->name(), external_name(), init_thread_name());
1225 }
1226 wait = true;
1227 jt->set_class_to_be_initialized(this);
1228 ol.wait_uninterruptibly(jt);
1229 jt->set_class_to_be_initialized(nullptr);
1230 }
1231
1232 // Step 3
1233 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1234 if (debug_logging_enabled) {
1235 ResourceMark rm(jt);
1236 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1237 jt->name(), external_name());
1238 }
1239 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1240 return;
1241 }
1242
1243 // Step 4
1244 if (is_initialized()) {
1245 if (debug_logging_enabled) {
1246 ResourceMark rm(jt);
1247 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1248 jt->name(), external_name());
1249 }
1250 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1251 return;
1252 }
1253
1254 // Step 5
1255 if (is_in_error_state()) {
1256 if (debug_logging_enabled) {
1257 ResourceMark rm(jt);
1258 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1259 jt->name(), external_name());
1260 }
1261
1262 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1263 ResourceMark rm(THREAD);
1264 Handle cause(THREAD, get_initialization_error(THREAD));
1265
1266 stringStream ss;
1267 ss.print("Could not initialize class %s", external_name());
1268 if (cause.is_null()) {
1269 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1270 } else {
1271 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1272 ss.as_string(), cause);
1273 }
1274 } else {
1275
1276 // Step 6
1277 set_init_state(being_initialized);
1278 set_init_thread(jt);
1279 if (debug_logging_enabled) {
1280 ResourceMark rm(jt);
1281 log_debug(class, init)("Thread \"%s\" is initializing %s",
1282 jt->name(), external_name());
1283 }
1284 }
1285 }
1286
1287 // Step 7
1288 // Next, if C is a class rather than an interface, initialize it's super class and super
1289 // interfaces.
1290 if (!is_interface()) {
1291 Klass* super_klass = super();
1292 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1293 super_klass->initialize(THREAD);
1294 }
1295 // If C implements any interface that declares a non-static, concrete method,
1296 // the initialization of C triggers initialization of its super interfaces.
1297 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1298 // having a superinterface that declares, non-static, concrete methods
1299 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1300 initialize_super_interfaces(THREAD);
1301 }
1302
1303 // If any exceptions, complete abruptly, throwing the same exception as above.
1304 if (HAS_PENDING_EXCEPTION) {
1305 Handle e(THREAD, PENDING_EXCEPTION);
1306 CLEAR_PENDING_EXCEPTION;
1307 {
1308 EXCEPTION_MARK;
1309 add_initialization_error(THREAD, e);
1310 // Locks object, set state, and notify all waiting threads
1311 set_initialization_state_and_notify(initialization_error, THREAD);
1312 CLEAR_PENDING_EXCEPTION;
1313 }
1314 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1315 THROW_OOP(e());
1316 }
1317 }
1318
1319
1320 // Step 8
1321 {
1322 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1323 if (class_initializer() != nullptr) {
1324 // Timer includes any side effects of class initialization (resolution,
1325 // etc), but not recursive entry into call_class_initializer().
1326 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1327 ClassLoader::perf_class_init_selftime(),
1328 ClassLoader::perf_classes_inited(),
1329 jt->get_thread_stat()->perf_recursion_counts_addr(),
1330 jt->get_thread_stat()->perf_timers_addr(),
1331 PerfClassTraceTime::CLASS_CLINIT);
1332 call_class_initializer(THREAD);
1333 } else {
1334 // The elapsed time is so small it's not worth counting.
1335 if (UsePerfData) {
1336 ClassLoader::perf_classes_inited()->inc();
1337 }
1338 call_class_initializer(THREAD);
1339 }
1340 }
1341
1342 // Step 9
1343 if (!HAS_PENDING_EXCEPTION) {
1344 set_initialization_state_and_notify(fully_initialized, CHECK);
1345 debug_only(vtable().verify(tty, true);)
1346 CompilationPolicy::replay_training_at_init(this, THREAD);
1347 }
1348 else {
1349 // Step 10 and 11
1350 Handle e(THREAD, PENDING_EXCEPTION);
1351 CLEAR_PENDING_EXCEPTION;
1352 // JVMTI has already reported the pending exception
1353 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1354 JvmtiExport::clear_detected_exception(jt);
1355 {
1356 EXCEPTION_MARK;
1357 add_initialization_error(THREAD, e);
1358 set_initialization_state_and_notify(initialization_error, THREAD);
1359 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1360 // JVMTI has already reported the pending exception
1361 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1362 JvmtiExport::clear_detected_exception(jt);
1363 }
1364 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1365 if (e->is_a(vmClasses::Error_klass())) {
1366 THROW_OOP(e());
1367 } else {
1368 JavaCallArguments args(e);
1369 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1370 vmSymbols::throwable_void_signature(),
1371 &args);
1372 }
1373 }
1374 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1375 }
1376
1377 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1378 Handle h_init_lock(THREAD, init_lock());
1379 if (h_init_lock() != nullptr) {
1380 ObjectLocker ol(h_init_lock, THREAD);
1381 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1382 set_init_state(state);
1383 fence_and_clear_init_lock();
1384 ol.notify_all(CHECK);
1385 } else {
1386 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1387 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1388 set_init_state(state);
1389 }
1390 }
1391
1392 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1393 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1394 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1395 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1396
1397 DeoptimizationScope deopt_scope;
1398 {
1399 MutexLocker ml(current, Compile_lock);
1400
1401 set_init_state(InstanceKlass::loaded);
1402 // make sure init_state store is already done.
1403 // The compiler reads the hierarchy outside of the Compile_lock.
1404 // Access ordering is used to add to hierarchy.
1405
1406 // Link into hierarchy.
1407 append_to_sibling_list(); // add to superklass/sibling list
1408 process_interfaces(); // handle all "implements" declarations
1409
1410 // Now mark all code that depended on old class hierarchy.
1411 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1412 if (Universe::is_fully_initialized()) {
1413 CodeCache::mark_dependents_on(&deopt_scope, this);
1414 }
1415 }
1416 // Perform the deopt handshake outside Compile_lock.
1417 deopt_scope.deoptimize_marked();
1418 }
1419
1420
1421 InstanceKlass* InstanceKlass::implementor() const {
1422 InstanceKlass* volatile* ik = adr_implementor();
1423 if (ik == nullptr) {
1424 return nullptr;
1425 } else {
1426 // This load races with inserts, and therefore needs acquire.
1427 InstanceKlass* ikls = Atomic::load_acquire(ik);
1428 if (ikls != nullptr && !ikls->is_loader_alive()) {
1429 return nullptr; // don't return unloaded class
1430 } else {
1431 return ikls;
1432 }
1433 }
1434 }
1435
1436
1437 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1438 assert_locked_or_safepoint(Compile_lock);
1439 assert(is_interface(), "not interface");
1440 InstanceKlass* volatile* addr = adr_implementor();
1441 assert(addr != nullptr, "null addr");
1442 if (addr != nullptr) {
1443 Atomic::release_store(addr, ik);
1444 }
1445 }
1446
1447 int InstanceKlass::nof_implementors() const {
1448 InstanceKlass* ik = implementor();
1449 if (ik == nullptr) {
1450 return 0;
1451 } else if (ik != this) {
1452 return 1;
1453 } else {
1454 return 2;
1455 }
1456 }
1457
1458 // The embedded _implementor field can only record one implementor.
1459 // When there are more than one implementors, the _implementor field
1460 // is set to the interface Klass* itself. Following are the possible
1461 // values for the _implementor field:
1462 // null - no implementor
1463 // implementor Klass* - one implementor
1464 // self - more than one implementor
1465 //
1466 // The _implementor field only exists for interfaces.
1467 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1468 if (Universe::is_fully_initialized()) {
1469 assert_lock_strong(Compile_lock);
1470 }
1471 assert(is_interface(), "not interface");
1472 // Filter out my subinterfaces.
1473 // (Note: Interfaces are never on the subklass list.)
1474 if (ik->is_interface()) return;
1475
1476 // Filter out subclasses whose supers already implement me.
1477 // (Note: CHA must walk subclasses of direct implementors
1478 // in order to locate indirect implementors.)
1479 InstanceKlass* super_ik = ik->java_super();
1480 if (super_ik != nullptr && super_ik->implements_interface(this))
1481 // We only need to check one immediate superclass, since the
1482 // implements_interface query looks at transitive_interfaces.
1483 // Any supers of the super have the same (or fewer) transitive_interfaces.
1484 return;
1485
1486 InstanceKlass* iklass = implementor();
1487 if (iklass == nullptr) {
1488 set_implementor(ik);
1489 } else if (iklass != this && iklass != ik) {
1490 // There is already an implementor. Use itself as an indicator of
1491 // more than one implementors.
1492 set_implementor(this);
1493 }
1494
1495 // The implementor also implements the transitive_interfaces
1496 for (int index = 0; index < local_interfaces()->length(); index++) {
1497 local_interfaces()->at(index)->add_implementor(ik);
1498 }
1499 }
1500
1501 void InstanceKlass::init_implementor() {
1502 if (is_interface()) {
1503 set_implementor(nullptr);
1504 }
1505 }
1506
1507
1508 void InstanceKlass::process_interfaces() {
1509 // link this class into the implementors list of every interface it implements
1510 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1511 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1512 InstanceKlass* interf = local_interfaces()->at(i);
1513 assert(interf->is_interface(), "expected interface");
1514 interf->add_implementor(this);
1515 }
1516 }
1517
1518 bool InstanceKlass::can_be_primary_super_slow() const {
1519 if (is_interface())
1520 return false;
1521 else
1522 return Klass::can_be_primary_super_slow();
1523 }
1524
1525 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1526 Array<InstanceKlass*>* transitive_interfaces) {
1527 // The secondaries are the implemented interfaces.
1528 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1529 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1530 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1531 int num_secondaries = num_extra_slots + interfaces->length();
1532 if (num_secondaries == 0) {
1533 // Must share this for correct bootstrapping!
1534 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1535 return nullptr;
1536 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1537 // We will reuse the transitive interfaces list if we're certain
1538 // it's in hash order.
1539 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1540 set_secondary_supers(interfaces, bitmap);
1541 return nullptr;
1542 }
1543 // Copy transitive interfaces to a temporary growable array to be constructed
1544 // into the secondary super list with extra slots.
1545 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1546 for (int i = 0; i < interfaces->length(); i++) {
1547 secondaries->push(interfaces->at(i));
1548 }
1549 return secondaries;
1550 }
1551
1552 bool InstanceKlass::implements_interface(Klass* k) const {
1553 if (this == k) return true;
1554 assert(k->is_interface(), "should be an interface class");
1555 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1556 if (transitive_interfaces()->at(i) == k) {
1557 return true;
1558 }
1559 }
1560 return false;
1561 }
1562
1563 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1564 // Verify direct super interface
1565 if (this == k) return true;
1566 assert(k->is_interface(), "should be an interface class");
1567 for (int i = 0; i < local_interfaces()->length(); i++) {
1568 if (local_interfaces()->at(i) == k) {
1569 return true;
1570 }
1571 }
1572 return false;
1573 }
1574
1575 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1576 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1577 size_t size = objArrayOopDesc::object_size(length);
1578 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1579 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1580 /* do_zero */ true, CHECK_NULL);
1581 return o;
1582 }
1583
1584 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1585 if (TraceFinalizerRegistration) {
1586 tty->print("Registered ");
1587 i->print_value_on(tty);
1588 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1589 }
1590 instanceHandle h_i(THREAD, i);
1591 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1592 JavaValue result(T_VOID);
1593 JavaCallArguments args(h_i);
1594 methodHandle mh(THREAD, Universe::finalizer_register_method());
1595 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1596 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1597 return h_i();
1598 }
1599
1600 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1601 assert(!is_abstract() && !is_interface(), "Should not create this object");
1602 size_t size = size_helper(); // Query before forming handle.
1603 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1604 }
1605
1606 instanceOop InstanceKlass::allocate_instance(oop java_class,
1607 const char* who,
1608 TRAPS) {
1609 Klass* k = java_lang_Class::as_Klass(java_class);
1610 if (k == nullptr) {
1611 ResourceMark rm(THREAD);
1612 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1613 }
1614 InstanceKlass* ik = cast(k);
1615 ik->check_valid_for_instantiation(false, CHECK_NULL);
1616 ik->initialize(CHECK_NULL);
1617 return ik->allocate_instance(THREAD);
1618 }
1619
1620 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1621 return instanceHandle(THREAD, allocate_instance(THREAD));
1622 }
1623
1624 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1625 if (is_interface() || is_abstract()) {
1626 ResourceMark rm(THREAD);
1627 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1628 : vmSymbols::java_lang_InstantiationException(), external_name());
1629 }
1630 if (this == vmClasses::Class_klass()) {
1631 ResourceMark rm(THREAD);
1632 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1633 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1634 }
1635 }
1636
1637 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1638 // Need load-acquire for lock-free read
1639 if (array_klasses_acquire() == nullptr) {
1640
1641 // Recursively lock array allocation
1642 RecursiveLocker rl(MultiArray_lock, THREAD);
1643
1644 // Check if another thread created the array klass while we were waiting for the lock.
1645 if (array_klasses() == nullptr) {
1646 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1647 // use 'release' to pair with lock-free load
1648 release_set_array_klasses(k);
1649 }
1650 }
1651
1652 // array_klasses() will always be set at this point
1653 ObjArrayKlass* ak = array_klasses();
1654 assert(ak != nullptr, "should be set");
1655 return ak->array_klass(n, THREAD);
1656 }
1657
1658 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1659 // Need load-acquire for lock-free read
1660 ObjArrayKlass* oak = array_klasses_acquire();
1661 if (oak == nullptr) {
1662 return nullptr;
1663 } else {
1664 return oak->array_klass_or_null(n);
1665 }
1666 }
1667
1668 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1669 return array_klass(1, THREAD);
1670 }
1671
1672 ArrayKlass* InstanceKlass::array_klass_or_null() {
1673 return array_klass_or_null(1);
1674 }
1675
1676 Method* InstanceKlass::class_initializer() const {
1677 Method* clinit = find_method(
1678 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1679 if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
1680 return clinit;
1681 }
1682 return nullptr;
1683 }
1684
1685 void InstanceKlass::call_class_initializer(TRAPS) {
1686 if (ReplayCompiles &&
1687 (ReplaySuppressInitializers == 1 ||
1688 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1689 // Hide the existence of the initializer for the purpose of replaying the compile
1690 return;
1691 }
1692
1693 #if INCLUDE_CDS
1694 // This is needed to ensure the consistency of the archived heap objects.
1695 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) {
1696 AOTClassInitializer::call_runtime_setup(THREAD, this);
1697 return;
1698 } else if (has_archived_enum_objs()) {
1699 assert(is_shared(), "must be");
1700 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1701 if (initialized) {
1702 return;
1703 }
1704 }
1705 #endif
1706
1707 methodHandle h_method(THREAD, class_initializer());
1708 assert(!is_initialized(), "we cannot initialize twice");
1709
1710 #if 0
1711 // FIXME -- revive this code added to leyden/premain for <clinit> profiling
1712 int init_id = log_class_init(THREAD, this);
1713 if (h_method() != nullptr) {
1714 JavaCallArguments args; // No arguments
1715 JavaValue result(T_VOID);
1716 InstanceKlass* outer = THREAD->set_class_being_initialized(this);
1717 jlong bc_start = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1718
1719 elapsedTimer timer;
1720 {
1721 PerfPauseTimer pt(THREAD->current_rt_call_timer(), THREAD->profile_rt_calls());
1722 PauseRuntimeCallProfiling prcp(THREAD, THREAD->profile_rt_calls());
1723
1724 timer.start();
1725 JavaCalls::call(&result, h_method, &args, THREAD); // Static call (no args)
1726 timer.stop();
1727 }
1728
1729 jlong bc_end = (CountBytecodesPerThread ? THREAD->bc_counter_value() : BytecodeCounter::counter_value());
1730
1731 jlong bc_executed = (bc_end - bc_start);
1732 if (UsePerfData && outer == nullptr) { // outermost clinit
1733 THREAD->inc_clinit_bc_counter_value(bc_executed);
1734 ClassLoader::perf_class_init_bytecodes_count()->inc(bc_executed);
1735 }
1736
1737 THREAD->set_class_being_initialized(outer);
1738
1739 LogStreamHandle(Debug, init) log;
1740 if (log.is_enabled()) {
1741 ResourceMark rm(THREAD);
1742 log.print("%d Initialized in %.3fms (total: " JLONG_FORMAT "ms); ",
1743 init_id, timer.seconds() * 1000.0, ClassLoader::class_init_time_ms());
1744 if (CountBytecodes || CountBytecodesPerThread) {
1745 log.print("executed " JLONG_FORMAT " bytecodes; ", bc_executed);
1746 }
1747 name()->print_value_on(&log);
1748 log.print_cr(" by thread " PTR_FORMAT " \"%s\" (" PTR_FORMAT ")",
1749 p2i(THREAD), THREAD->name(), p2i(this));
1750 }
1751 }
1752 LogTarget(Info, class, init) lt;
1753 if (lt.is_enabled()) {
1754 ResourceMark rm(THREAD);
1755 LogStream ls(lt);
1756 ls.print("%d Initialized ", init_id);
1757 name()->print_value_on(&ls);
1758 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1759 h_method() == nullptr ? "(no method)" : "", p2i(this),
1760 THREAD->name());
1761 }
1762 #else
1763 static int call_class_initializer_counter = 0; // for debugging
1764 LogTarget(Info, class, init) lt;
1765 if (lt.is_enabled()) {
1766 ResourceMark rm(THREAD);
1767 LogStream ls(lt);
1768 ls.print("%d Initializing ", call_class_initializer_counter++);
1769 name()->print_value_on(&ls);
1770 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1771 h_method() == nullptr ? "(no method)" : "", p2i(this),
1772 THREAD->name());
1773 }
1774 if (h_method() != nullptr) {
1775 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized
1776 JavaCallArguments args; // No arguments
1777 JavaValue result(T_VOID);
1778 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1779 }
1780 #endif
1781 }
1782
1783 // If a class that implements this interface is initialized, is the JVM required
1784 // to first execute a <clinit> method declared in this interface,
1785 // or (if also_check_supers==true) any of the super types of this interface?
1786 //
1787 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than
1788 // an interface, then let SC be its superclass and let SI1, ..., SIn
1789 // be all superinterfaces of C (whether direct or indirect) that
1790 // declare at least one non-abstract, non-static method.
1791 //
1792 // So when an interface is initialized, it does not look at its
1793 // supers. But a proper class will ensure that all of its supers have
1794 // run their <clinit> methods, except that it disregards interfaces
1795 // that lack a non-static concrete method (i.e., a default method).
1796 // Therefore, you should probably call this method only when the
1797 // current class is a super of some proper class, not an interface.
1798 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const {
1799 assert(is_interface(), "must be");
1800
1801 if (!has_nonstatic_concrete_methods()) {
1802 // quick check: no nonstatic concrete methods are declared by this or any super interfaces
1803 return false;
1804 }
1805
1806 // JVMS 5.5. Initialization
1807 // ...If C is an interface that declares a non-abstract,
1808 // non-static method, the initialization of a class that
1809 // implements C directly or indirectly.
1810 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) {
1811 return true;
1812 }
1813 if (also_check_supers) {
1814 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1815 for (int i = 0; i < all_ifs->length(); ++i) {
1816 InstanceKlass* super_intf = all_ifs->at(i);
1817 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) {
1818 return true;
1819 }
1820 }
1821 }
1822 return false;
1823 }
1824
1825 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1826 InterpreterOopMap* entry_for) {
1827 // Lazily create the _oop_map_cache at first request.
1828 // Load_acquire is needed to safely get instance published with CAS by another thread.
1829 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1830 if (oop_map_cache == nullptr) {
1831 // Try to install new instance atomically.
1832 oop_map_cache = new OopMapCache();
1833 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1834 if (other != nullptr) {
1835 // Someone else managed to install before us, ditch local copy and use the existing one.
1836 delete oop_map_cache;
1837 oop_map_cache = other;
1838 }
1839 }
1840 // _oop_map_cache is constant after init; lookup below does its own locking.
1841 oop_map_cache->lookup(method, bci, entry_for);
1842 }
1843
1844 bool InstanceKlass::contains_field_offset(int offset) {
1845 fieldDescriptor fd;
1846 return find_field_from_offset(offset, false, &fd);
1847 }
1848
1849 FieldInfo InstanceKlass::field(int index) const {
1850 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1851 if (fs.index() == index) {
1852 return fs.to_FieldInfo();
1853 }
1854 }
1855 fatal("Field not found");
1856 return FieldInfo();
1857 }
1858
1859 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1860 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1861 Symbol* f_name = fs.name();
1862 Symbol* f_sig = fs.signature();
1863 if (f_name == name && f_sig == sig) {
1864 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1865 return true;
1866 }
1867 }
1868 return false;
1869 }
1870
1871
1872 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1873 const int n = local_interfaces()->length();
1874 for (int i = 0; i < n; i++) {
1875 Klass* intf1 = local_interfaces()->at(i);
1876 assert(intf1->is_interface(), "just checking type");
1877 // search for field in current interface
1878 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1879 assert(fd->is_static(), "interface field must be static");
1880 return intf1;
1881 }
1882 // search for field in direct superinterfaces
1883 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1884 if (intf2 != nullptr) return intf2;
1885 }
1886 // otherwise field lookup fails
1887 return nullptr;
1888 }
1889
1890
1891 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1892 // search order according to newest JVM spec (5.4.3.2, p.167).
1893 // 1) search for field in current klass
1894 if (find_local_field(name, sig, fd)) {
1895 return const_cast<InstanceKlass*>(this);
1896 }
1897 // 2) search for field recursively in direct superinterfaces
1898 { Klass* intf = find_interface_field(name, sig, fd);
1899 if (intf != nullptr) return intf;
1900 }
1901 // 3) apply field lookup recursively if superclass exists
1902 { Klass* supr = super();
1903 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1904 }
1905 // 4) otherwise field lookup fails
1906 return nullptr;
1907 }
1908
1909
1910 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1911 // search order according to newest JVM spec (5.4.3.2, p.167).
1912 // 1) search for field in current klass
1913 if (find_local_field(name, sig, fd)) {
1914 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1915 }
1916 // 2) search for field recursively in direct superinterfaces
1917 if (is_static) {
1918 Klass* intf = find_interface_field(name, sig, fd);
1919 if (intf != nullptr) return intf;
1920 }
1921 // 3) apply field lookup recursively if superclass exists
1922 { Klass* supr = super();
1923 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1924 }
1925 // 4) otherwise field lookup fails
1926 return nullptr;
1927 }
1928
1929
1930 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1931 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1932 if (fs.offset() == offset) {
1933 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1934 if (fd->is_static() == is_static) return true;
1935 }
1936 }
1937 return false;
1938 }
1939
1940
1941 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1942 Klass* klass = const_cast<InstanceKlass*>(this);
1943 while (klass != nullptr) {
1944 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1945 return true;
1946 }
1947 klass = klass->super();
1948 }
1949 return false;
1950 }
1951
1952
1953 void InstanceKlass::methods_do(void f(Method* method)) {
1954 // Methods aren't stable until they are loaded. This can be read outside
1955 // a lock through the ClassLoaderData for profiling
1956 // Redefined scratch classes are on the list and need to be cleaned
1957 if (!is_loaded() && !is_scratch_class()) {
1958 return;
1959 }
1960
1961 int len = methods()->length();
1962 for (int index = 0; index < len; index++) {
1963 Method* m = methods()->at(index);
1964 assert(m->is_method(), "must be method");
1965 f(m);
1966 }
1967 }
1968
1969
1970 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1971 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1972 if (fs.access_flags().is_static()) {
1973 fieldDescriptor& fd = fs.field_descriptor();
1974 cl->do_field(&fd);
1975 }
1976 }
1977 }
1978
1979
1980 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1981 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1982 if (fs.access_flags().is_static()) {
1983 fieldDescriptor& fd = fs.field_descriptor();
1984 f(&fd, mirror, CHECK);
1985 }
1986 }
1987 }
1988
1989 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1990 InstanceKlass* super = superklass();
1991 if (super != nullptr) {
1992 super->do_nonstatic_fields(cl);
1993 }
1994 fieldDescriptor fd;
1995 int length = java_fields_count();
1996 for (int i = 0; i < length; i += 1) {
1997 fd.reinitialize(this, i);
1998 if (!fd.is_static()) {
1999 cl->do_field(&fd);
2000 }
2001 }
2002 }
2003
2004 // first in Pair is offset, second is index.
2005 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2006 return a->first - b->first;
2007 }
2008
2009 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2010 InstanceKlass* super = superklass();
2011 if (super != nullptr) {
2012 super->print_nonstatic_fields(cl);
2013 }
2014 ResourceMark rm;
2015 fieldDescriptor fd;
2016 // In DebugInfo nonstatic fields are sorted by offset.
2017 GrowableArray<Pair<int,int> > fields_sorted;
2018 int i = 0;
2019 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2020 if (!fs.access_flags().is_static()) {
2021 fd = fs.field_descriptor();
2022 Pair<int,int> f(fs.offset(), fs.index());
2023 fields_sorted.push(f);
2024 i++;
2025 }
2026 }
2027 if (i > 0) {
2028 int length = i;
2029 assert(length == fields_sorted.length(), "duh");
2030 fields_sorted.sort(compare_fields_by_offset);
2031 for (int i = 0; i < length; i++) {
2032 fd.reinitialize(this, fields_sorted.at(i).second);
2033 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2034 cl->do_field(&fd);
2035 }
2036 }
2037 }
2038
2039 #ifdef ASSERT
2040 static int linear_search(const Array<Method*>* methods,
2041 const Symbol* name,
2042 const Symbol* signature) {
2043 const int len = methods->length();
2044 for (int index = 0; index < len; index++) {
2045 const Method* const m = methods->at(index);
2046 assert(m->is_method(), "must be method");
2047 if (m->signature() == signature && m->name() == name) {
2048 return index;
2049 }
2050 }
2051 return -1;
2052 }
2053 #endif
2054
2055 bool InstanceKlass::_disable_method_binary_search = false;
2056
2057 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2058 int len = methods->length();
2059 int l = 0;
2060 int h = len - 1;
2061 while (l <= h) {
2062 Method* m = methods->at(l);
2063 if (m->name() == name) {
2064 return l;
2065 }
2066 l++;
2067 }
2068 return -1;
2069 }
2070
2071 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2072 if (_disable_method_binary_search) {
2073 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2074 // At the final stage of dynamic dumping, the methods array may not be sorted
2075 // by ascending addresses of their names, so we can't use binary search anymore.
2076 // However, methods with the same name are still laid out consecutively inside the
2077 // methods array, so let's look for the first one that matches.
2078 return linear_search(methods, name);
2079 }
2080
2081 int len = methods->length();
2082 int l = 0;
2083 int h = len - 1;
2084
2085 // methods are sorted by ascending addresses of their names, so do binary search
2086 while (l <= h) {
2087 int mid = (l + h) >> 1;
2088 Method* m = methods->at(mid);
2089 assert(m->is_method(), "must be method");
2090 int res = m->name()->fast_compare(name);
2091 if (res == 0) {
2092 return mid;
2093 } else if (res < 0) {
2094 l = mid + 1;
2095 } else {
2096 h = mid - 1;
2097 }
2098 }
2099 return -1;
2100 }
2101
2102 // find_method looks up the name/signature in the local methods array
2103 Method* InstanceKlass::find_method(const Symbol* name,
2104 const Symbol* signature) const {
2105 return find_method_impl(name, signature,
2106 OverpassLookupMode::find,
2107 StaticLookupMode::find,
2108 PrivateLookupMode::find);
2109 }
2110
2111 Method* InstanceKlass::find_method_impl(const Symbol* name,
2112 const Symbol* signature,
2113 OverpassLookupMode overpass_mode,
2114 StaticLookupMode static_mode,
2115 PrivateLookupMode private_mode) const {
2116 return InstanceKlass::find_method_impl(methods(),
2117 name,
2118 signature,
2119 overpass_mode,
2120 static_mode,
2121 private_mode);
2122 }
2123
2124 // find_instance_method looks up the name/signature in the local methods array
2125 // and skips over static methods
2126 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2127 const Symbol* name,
2128 const Symbol* signature,
2129 PrivateLookupMode private_mode) {
2130 Method* const meth = InstanceKlass::find_method_impl(methods,
2131 name,
2132 signature,
2133 OverpassLookupMode::find,
2134 StaticLookupMode::skip,
2135 private_mode);
2136 assert(((meth == nullptr) || !meth->is_static()),
2137 "find_instance_method should have skipped statics");
2138 return meth;
2139 }
2140
2141 // find_instance_method looks up the name/signature in the local methods array
2142 // and skips over static methods
2143 Method* InstanceKlass::find_instance_method(const Symbol* name,
2144 const Symbol* signature,
2145 PrivateLookupMode private_mode) const {
2146 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2147 }
2148
2149 // Find looks up the name/signature in the local methods array
2150 // and filters on the overpass, static and private flags
2151 // This returns the first one found
2152 // note that the local methods array can have up to one overpass, one static
2153 // and one instance (private or not) with the same name/signature
2154 Method* InstanceKlass::find_local_method(const Symbol* name,
2155 const Symbol* signature,
2156 OverpassLookupMode overpass_mode,
2157 StaticLookupMode static_mode,
2158 PrivateLookupMode private_mode) const {
2159 return InstanceKlass::find_method_impl(methods(),
2160 name,
2161 signature,
2162 overpass_mode,
2163 static_mode,
2164 private_mode);
2165 }
2166
2167 // Find looks up the name/signature in the local methods array
2168 // and filters on the overpass, static and private flags
2169 // This returns the first one found
2170 // note that the local methods array can have up to one overpass, one static
2171 // and one instance (private or not) with the same name/signature
2172 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2173 const Symbol* name,
2174 const Symbol* signature,
2175 OverpassLookupMode overpass_mode,
2176 StaticLookupMode static_mode,
2177 PrivateLookupMode private_mode) {
2178 return InstanceKlass::find_method_impl(methods,
2179 name,
2180 signature,
2181 overpass_mode,
2182 static_mode,
2183 private_mode);
2184 }
2185
2186 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2187 const Symbol* name,
2188 const Symbol* signature) {
2189 return InstanceKlass::find_method_impl(methods,
2190 name,
2191 signature,
2192 OverpassLookupMode::find,
2193 StaticLookupMode::find,
2194 PrivateLookupMode::find);
2195 }
2196
2197 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2198 const Symbol* name,
2199 const Symbol* signature,
2200 OverpassLookupMode overpass_mode,
2201 StaticLookupMode static_mode,
2202 PrivateLookupMode private_mode) {
2203 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2204 return hit >= 0 ? methods->at(hit): nullptr;
2205 }
2206
2207 // true if method matches signature and conforms to skipping_X conditions.
2208 static bool method_matches(const Method* m,
2209 const Symbol* signature,
2210 bool skipping_overpass,
2211 bool skipping_static,
2212 bool skipping_private) {
2213 return ((m->signature() == signature) &&
2214 (!skipping_overpass || !m->is_overpass()) &&
2215 (!skipping_static || !m->is_static()) &&
2216 (!skipping_private || !m->is_private()));
2217 }
2218
2219 // Used directly for default_methods to find the index into the
2220 // default_vtable_indices, and indirectly by find_method
2221 // find_method_index looks in the local methods array to return the index
2222 // of the matching name/signature. If, overpass methods are being ignored,
2223 // the search continues to find a potential non-overpass match. This capability
2224 // is important during method resolution to prefer a static method, for example,
2225 // over an overpass method.
2226 // There is the possibility in any _method's array to have the same name/signature
2227 // for a static method, an overpass method and a local instance method
2228 // To correctly catch a given method, the search criteria may need
2229 // to explicitly skip the other two. For local instance methods, it
2230 // is often necessary to skip private methods
2231 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2232 const Symbol* name,
2233 const Symbol* signature,
2234 OverpassLookupMode overpass_mode,
2235 StaticLookupMode static_mode,
2236 PrivateLookupMode private_mode) {
2237 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2238 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2239 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2240 const int hit = quick_search(methods, name);
2241 if (hit != -1) {
2242 const Method* const m = methods->at(hit);
2243
2244 // Do linear search to find matching signature. First, quick check
2245 // for common case, ignoring overpasses if requested.
2246 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2247 return hit;
2248 }
2249
2250 // search downwards through overloaded methods
2251 int i;
2252 for (i = hit - 1; i >= 0; --i) {
2253 const Method* const m = methods->at(i);
2254 assert(m->is_method(), "must be method");
2255 if (m->name() != name) {
2256 break;
2257 }
2258 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2259 return i;
2260 }
2261 }
2262 // search upwards
2263 for (i = hit + 1; i < methods->length(); ++i) {
2264 const Method* const m = methods->at(i);
2265 assert(m->is_method(), "must be method");
2266 if (m->name() != name) {
2267 break;
2268 }
2269 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2270 return i;
2271 }
2272 }
2273 // not found
2274 #ifdef ASSERT
2275 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2276 linear_search(methods, name, signature);
2277 assert(-1 == index, "binary search should have found entry %d", index);
2278 #endif
2279 }
2280 return -1;
2281 }
2282
2283 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2284 return find_method_by_name(methods(), name, end);
2285 }
2286
2287 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2288 const Symbol* name,
2289 int* end_ptr) {
2290 assert(end_ptr != nullptr, "just checking");
2291 int start = quick_search(methods, name);
2292 int end = start + 1;
2293 if (start != -1) {
2294 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2295 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2296 *end_ptr = end;
2297 return start;
2298 }
2299 return -1;
2300 }
2301
2302 // uncached_lookup_method searches both the local class methods array and all
2303 // superclasses methods arrays, skipping any overpass methods in superclasses,
2304 // and possibly skipping private methods.
2305 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2306 const Symbol* signature,
2307 OverpassLookupMode overpass_mode,
2308 PrivateLookupMode private_mode) const {
2309 OverpassLookupMode overpass_local_mode = overpass_mode;
2310 const Klass* klass = this;
2311 while (klass != nullptr) {
2312 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2313 signature,
2314 overpass_local_mode,
2315 StaticLookupMode::find,
2316 private_mode);
2317 if (method != nullptr) {
2318 return method;
2319 }
2320 klass = klass->super();
2321 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2322 }
2323 return nullptr;
2324 }
2325
2326 #ifdef ASSERT
2327 // search through class hierarchy and return true if this class or
2328 // one of the superclasses was redefined
2329 bool InstanceKlass::has_redefined_this_or_super() const {
2330 const Klass* klass = this;
2331 while (klass != nullptr) {
2332 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2333 return true;
2334 }
2335 klass = klass->super();
2336 }
2337 return false;
2338 }
2339 #endif
2340
2341 // lookup a method in the default methods list then in all transitive interfaces
2342 // Do NOT return private or static methods
2343 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2344 Symbol* signature) const {
2345 Method* m = nullptr;
2346 if (default_methods() != nullptr) {
2347 m = find_method(default_methods(), name, signature);
2348 }
2349 // Look up interfaces
2350 if (m == nullptr) {
2351 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2352 }
2353 return m;
2354 }
2355
2356 // lookup a method in all the interfaces that this class implements
2357 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2358 // They should only be found in the initial InterfaceMethodRef
2359 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2360 Symbol* signature,
2361 DefaultsLookupMode defaults_mode) const {
2362 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2363 int num_ifs = all_ifs->length();
2364 InstanceKlass *ik = nullptr;
2365 for (int i = 0; i < num_ifs; i++) {
2366 ik = all_ifs->at(i);
2367 Method* m = ik->lookup_method(name, signature);
2368 if (m != nullptr && m->is_public() && !m->is_static() &&
2369 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2370 return m;
2371 }
2372 }
2373 return nullptr;
2374 }
2375
2376 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2377 :_st(st), _verbose(verbose) {
2378 ResourceMark rm;
2379 _st->print("%-18s ", "KlassAddr");
2380 _st->print("%-4s ", "Size");
2381 _st->print("%-20s ", "State");
2382 _st->print("%-7s ", "Flags");
2383 _st->print("%-5s ", "ClassName");
2384 _st->cr();
2385 }
2386
2387 void PrintClassClosure::do_klass(Klass* k) {
2388 ResourceMark rm;
2389 // klass pointer
2390 _st->print(PTR_FORMAT " ", p2i(k));
2391 // klass size
2392 _st->print("%4d ", k->size());
2393 // initialization state
2394 if (k->is_instance_klass()) {
2395 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2396 } else {
2397 _st->print("%-20s ","");
2398 }
2399 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2400 char buf[10];
2401 int i = 0;
2402 if (k->has_finalizer()) buf[i++] = 'F';
2403 if (k->is_instance_klass()) {
2404 InstanceKlass* ik = InstanceKlass::cast(k);
2405 if (ik->has_final_method()) buf[i++] = 'f';
2406 if (ik->is_rewritten()) buf[i++] = 'W';
2407 if (ik->is_contended()) buf[i++] = 'C';
2408 if (ik->has_been_redefined()) buf[i++] = 'R';
2409 if (ik->is_shared()) buf[i++] = 'S';
2410 }
2411 buf[i++] = '\0';
2412 _st->print("%-7s ", buf);
2413 // klass name
2414 _st->print("%-5s ", k->external_name());
2415 // end
2416 _st->cr();
2417 if (_verbose) {
2418 k->print_on(_st);
2419 }
2420 }
2421
2422 /* jni_id_for for jfieldIds only */
2423 JNIid* InstanceKlass::jni_id_for(int offset) {
2424 MutexLocker ml(JfieldIdCreation_lock);
2425 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2426 if (probe == nullptr) {
2427 // Allocate new static field identifier
2428 probe = new JNIid(this, offset, jni_ids());
2429 set_jni_ids(probe);
2430 }
2431 return probe;
2432 }
2433
2434 u2 InstanceKlass::enclosing_method_data(int offset) const {
2435 const Array<jushort>* const inner_class_list = inner_classes();
2436 if (inner_class_list == nullptr) {
2437 return 0;
2438 }
2439 const int length = inner_class_list->length();
2440 if (length % inner_class_next_offset == 0) {
2441 return 0;
2442 }
2443 const int index = length - enclosing_method_attribute_size;
2444 assert(offset < enclosing_method_attribute_size, "invalid offset");
2445 return inner_class_list->at(index + offset);
2446 }
2447
2448 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2449 u2 method_index) {
2450 Array<jushort>* inner_class_list = inner_classes();
2451 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2452 int length = inner_class_list->length();
2453 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2454 int index = length - enclosing_method_attribute_size;
2455 inner_class_list->at_put(
2456 index + enclosing_method_class_index_offset, class_index);
2457 inner_class_list->at_put(
2458 index + enclosing_method_method_index_offset, method_index);
2459 }
2460 }
2461
2462 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2463 if (method->is_old() && !method->is_obsolete()) {
2464 // If the method passed in is old (but not obsolete), use the current version.
2465 method = method_with_idnum((int)idnum);
2466 assert(method != nullptr, "old and but not obsolete, so should exist");
2467 }
2468 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2469 Atomic::release_store(&jmeths[idnum + 1], new_id);
2470 return new_id;
2471 }
2472
2473 // Lookup or create a jmethodID.
2474 // This code is called by the VMThread and JavaThreads so the
2475 // locking has to be done very carefully to avoid deadlocks
2476 // and/or other cache consistency problems.
2477 //
2478 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2479 Method* method = method_h();
2480 int idnum = method->method_idnum();
2481 jmethodID* jmeths = methods_jmethod_ids_acquire();
2482
2483 // We use a double-check locking idiom here because this cache is
2484 // performance sensitive. In the normal system, this cache only
2485 // transitions from null to non-null which is safe because we use
2486 // release_set_methods_jmethod_ids() to advertise the new cache.
2487 // A partially constructed cache should never be seen by a racing
2488 // thread. We also use release_store() to save a new jmethodID
2489 // in the cache so a partially constructed jmethodID should never be
2490 // seen either. Cache reads of existing jmethodIDs proceed without a
2491 // lock, but cache writes of a new jmethodID requires uniqueness and
2492 // creation of the cache itself requires no leaks so a lock is
2493 // acquired in those two cases.
2494 //
2495 // If the RedefineClasses() API has been used, then this cache grows
2496 // in the redefinition safepoint.
2497
2498 if (jmeths == nullptr) {
2499 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2500 jmeths = methods_jmethod_ids_acquire();
2501 // Still null?
2502 if (jmeths == nullptr) {
2503 size_t size = idnum_allocated_count();
2504 assert(size > (size_t)idnum, "should already have space");
2505 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2506 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2507 // cache size is stored in element[0], other elements offset by one
2508 jmeths[0] = (jmethodID)size;
2509 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2510
2511 // publish jmeths
2512 release_set_methods_jmethod_ids(jmeths);
2513 return new_id;
2514 }
2515 }
2516
2517 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2518 if (id == nullptr) {
2519 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2520 id = jmeths[idnum + 1];
2521 // Still null?
2522 if (id == nullptr) {
2523 return update_jmethod_id(jmeths, method, idnum);
2524 }
2525 }
2526 return id;
2527 }
2528
2529 void InstanceKlass::update_methods_jmethod_cache() {
2530 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2531 jmethodID* cache = _methods_jmethod_ids;
2532 if (cache != nullptr) {
2533 size_t size = idnum_allocated_count();
2534 size_t old_size = (size_t)cache[0];
2535 if (old_size < size + 1) {
2536 // Allocate a larger one and copy entries to the new one.
2537 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2538 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2539 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2540 // The cache size is stored in element[0]; the other elements are offset by one.
2541 new_cache[0] = (jmethodID)size;
2542
2543 for (int i = 1; i <= (int)old_size; i++) {
2544 new_cache[i] = cache[i];
2545 }
2546 _methods_jmethod_ids = new_cache;
2547 FREE_C_HEAP_ARRAY(jmethodID, cache);
2548 }
2549 }
2550 }
2551
2552 // Figure out how many jmethodIDs haven't been allocated, and make
2553 // sure space for them is pre-allocated. This makes getting all
2554 // method ids much, much faster with classes with more than 8
2555 // methods, and has a *substantial* effect on performance with jvmti
2556 // code that loads all jmethodIDs for all classes.
2557 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2558 int new_jmeths = 0;
2559 int length = methods()->length();
2560 for (int index = start_offset; index < length; index++) {
2561 Method* m = methods()->at(index);
2562 jmethodID id = m->find_jmethod_id_or_null();
2563 if (id == nullptr) {
2564 new_jmeths++;
2565 }
2566 }
2567 if (new_jmeths != 0) {
2568 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2569 }
2570 }
2571
2572 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2573 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2574 int idnum = method->method_idnum();
2575 jmethodID* jmeths = methods_jmethod_ids_acquire();
2576 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2577 }
2578
2579 inline DependencyContext InstanceKlass::dependencies() {
2580 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2581 return dep_context;
2582 }
2583
2584 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2585 dependencies().mark_dependent_nmethods(deopt_scope, changes, this);
2586 }
2587
2588 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2589 dependencies().add_dependent_nmethod(nm);
2590 }
2591
2592 void InstanceKlass::clean_dependency_context() {
2593 dependencies().clean_unloading_dependents();
2594 }
2595
2596 #ifndef PRODUCT
2597 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2598 dependencies().print_dependent_nmethods(verbose);
2599 }
2600
2601 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2602 return dependencies().is_dependent_nmethod(nm);
2603 }
2604 #endif //PRODUCT
2605
2606 void InstanceKlass::clean_weak_instanceklass_links() {
2607 clean_implementors_list();
2608 clean_method_data();
2609 }
2610
2611 void InstanceKlass::clean_implementors_list() {
2612 assert(is_loader_alive(), "this klass should be live");
2613 if (is_interface()) {
2614 assert (ClassUnloading, "only called for ClassUnloading");
2615 for (;;) {
2616 // Use load_acquire due to competing with inserts
2617 InstanceKlass* volatile* iklass = adr_implementor();
2618 assert(iklass != nullptr, "Klass must not be null");
2619 InstanceKlass* impl = Atomic::load_acquire(iklass);
2620 if (impl != nullptr && !impl->is_loader_alive()) {
2621 // null this field, might be an unloaded instance klass or null
2622 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2623 // Successfully unlinking implementor.
2624 if (log_is_enabled(Trace, class, unload)) {
2625 ResourceMark rm;
2626 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2627 }
2628 return;
2629 }
2630 } else {
2631 return;
2632 }
2633 }
2634 }
2635 }
2636
2637 void InstanceKlass::clean_method_data() {
2638 for (int m = 0; m < methods()->length(); m++) {
2639 MethodData* mdo = methods()->at(m)->method_data();
2640 if (mdo != nullptr) {
2641 mdo->clean_method_data(/*always_clean*/false);
2642 }
2643 }
2644 }
2645
2646 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2647 Klass::metaspace_pointers_do(it);
2648
2649 if (log_is_enabled(Trace, cds)) {
2650 ResourceMark rm;
2651 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2652 }
2653
2654 it->push(&_annotations);
2655 it->push((Klass**)&_array_klasses);
2656 if (!is_rewritten()) {
2657 it->push(&_constants, MetaspaceClosure::_writable);
2658 } else {
2659 it->push(&_constants);
2660 }
2661 it->push(&_inner_classes);
2662 #if INCLUDE_JVMTI
2663 it->push(&_previous_versions);
2664 #endif
2665 #if INCLUDE_CDS
2666 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2667 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2668 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2669 // The length check on the _methods is necessary because classes which don't have any
2670 // methods share the Universe::_the_empty_method_array which is in the RO region.
2671 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2672 // To handle jsr bytecode, new Method* maybe stored into _methods
2673 it->push(&_methods, MetaspaceClosure::_writable);
2674 } else {
2675 #endif
2676 it->push(&_methods);
2677 #if INCLUDE_CDS
2678 }
2679 #endif
2680 it->push(&_default_methods);
2681 it->push(&_local_interfaces);
2682 it->push(&_transitive_interfaces);
2683 it->push(&_method_ordering);
2684 if (!is_rewritten()) {
2685 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2686 } else {
2687 it->push(&_default_vtable_indices);
2688 }
2689
2690 it->push(&_fieldinfo_stream);
2691 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2692 it->push(&_fields_status, MetaspaceClosure::_writable);
2693
2694 if (itable_length() > 0) {
2695 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2696 int method_table_offset_in_words = ioe->offset()/wordSize;
2697 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2698
2699 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2700 / itableOffsetEntry::size();
2701
2702 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2703 if (ioe->interface_klass() != nullptr) {
2704 it->push(ioe->interface_klass_addr());
2705 itableMethodEntry* ime = ioe->first_method_entry(this);
2706 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2707 for (int index = 0; index < n; index ++) {
2708 it->push(ime[index].method_addr());
2709 }
2710 }
2711 }
2712 }
2713
2714 it->push(&_nest_host);
2715 it->push(&_nest_members);
2716 it->push(&_permitted_subclasses);
2717 it->push(&_record_components);
2718 }
2719
2720 #if INCLUDE_CDS
2721 void InstanceKlass::remove_unshareable_info() {
2722 if (is_linked()) {
2723 assert(can_be_verified_at_dumptime(), "must be");
2724 // Remember this so we can avoid walking the hierarchy at runtime.
2725 set_verified_at_dump_time();
2726 }
2727 _misc_flags.set_has_init_deps_processed(false);
2728
2729 Klass::remove_unshareable_info();
2730
2731 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2732 // Classes are attempted to link during dumping and may fail,
2733 // but these classes are still in the dictionary and class list in CLD.
2734 // If the class has failed verification, there is nothing else to remove.
2735 return;
2736 }
2737
2738 // Reset to the 'allocated' state to prevent any premature accessing to
2739 // a shared class at runtime while the class is still being loaded and
2740 // restored. A class' init_state is set to 'loaded' at runtime when it's
2741 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2742 _init_state = allocated;
2743
2744 { // Otherwise this needs to take out the Compile_lock.
2745 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2746 init_implementor();
2747 }
2748
2749 // Call remove_unshareable_info() on other objects that belong to this class, except
2750 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2751 // ArchiveBuilder::make_klasses_shareable(),
2752
2753 for (int i = 0; i < methods()->length(); i++) {
2754 Method* m = methods()->at(i);
2755 m->remove_unshareable_info();
2756 }
2757
2758 // do array classes also.
2759 if (array_klasses() != nullptr) {
2760 array_klasses()->remove_unshareable_info();
2761 }
2762
2763 // These are not allocated from metaspace. They are safe to set to null.
2764 _source_debug_extension = nullptr;
2765 _dep_context = nullptr;
2766 _osr_nmethods_head = nullptr;
2767 #if INCLUDE_JVMTI
2768 _breakpoints = nullptr;
2769 _previous_versions = nullptr;
2770 _cached_class_file = nullptr;
2771 _jvmti_cached_class_field_map = nullptr;
2772 #endif
2773
2774 _init_thread = nullptr;
2775 _methods_jmethod_ids = nullptr;
2776 _jni_ids = nullptr;
2777 _oop_map_cache = nullptr;
2778 if (CDSConfig::is_dumping_invokedynamic() && HeapShared::is_lambda_proxy_klass(this)) {
2779 // keep _nest_host
2780 } else {
2781 // clear _nest_host to ensure re-load at runtime
2782 _nest_host = nullptr;
2783 }
2784 init_shared_package_entry();
2785 _dep_context_last_cleaned = 0;
2786 DEBUG_ONLY(_shared_class_load_count = 0);
2787
2788 remove_unshareable_flags();
2789 }
2790
2791 void InstanceKlass::remove_unshareable_flags() {
2792 // clear all the flags/stats that shouldn't be in the archived version
2793 assert(!is_scratch_class(), "must be");
2794 assert(!has_been_redefined(), "must be");
2795 #if INCLUDE_JVMTI
2796 set_is_being_redefined(false);
2797 #endif
2798 set_has_resolved_methods(false);
2799 }
2800
2801 void InstanceKlass::remove_java_mirror() {
2802 Klass::remove_java_mirror();
2803
2804 // do array classes also.
2805 if (array_klasses() != nullptr) {
2806 array_klasses()->remove_java_mirror();
2807 }
2808 }
2809
2810 void InstanceKlass::init_shared_package_entry() {
2811 assert(CDSConfig::is_dumping_archive(), "must be");
2812 #if !INCLUDE_CDS_JAVA_HEAP
2813 _package_entry = nullptr;
2814 #else
2815 if (CDSConfig::is_dumping_full_module_graph()) {
2816 if (is_shared_unregistered_class()) {
2817 _package_entry = nullptr;
2818 } else {
2819 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2820 }
2821 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2822 CDSConfig::is_using_full_module_graph() &&
2823 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2824 // _package_entry is an archived package in the base archive. Leave it as is.
2825 } else {
2826 _package_entry = nullptr;
2827 }
2828 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2829 #endif
2830 }
2831
2832 void InstanceKlass::compute_has_loops_flag_for_methods() {
2833 Array<Method*>* methods = this->methods();
2834 for (int index = 0; index < methods->length(); ++index) {
2835 Method* m = methods->at(index);
2836 if (!m->is_overpass()) { // work around JDK-8305771
2837 m->compute_has_loops_flag();
2838 }
2839 }
2840 }
2841
2842 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2843 PackageEntry* pkg_entry, TRAPS) {
2844 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2845 // before the InstanceKlass is added to the SystemDictionary. Make
2846 // sure the current state is <loaded.
2847 assert(!is_loaded(), "invalid init state");
2848 assert(!shared_loading_failed(), "Must not try to load failed class again");
2849 set_package(loader_data, pkg_entry, CHECK);
2850 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2851
2852 Array<Method*>* methods = this->methods();
2853 int num_methods = methods->length();
2854 for (int index = 0; index < num_methods; ++index) {
2855 methods->at(index)->restore_unshareable_info(CHECK);
2856 }
2857 #if INCLUDE_JVMTI
2858 if (JvmtiExport::has_redefined_a_class()) {
2859 // Reinitialize vtable because RedefineClasses may have changed some
2860 // entries in this vtable for super classes so the CDS vtable might
2861 // point to old or obsolete entries. RedefineClasses doesn't fix up
2862 // vtables in the shared system dictionary, only the main one.
2863 // It also redefines the itable too so fix that too.
2864 // First fix any default methods that point to a super class that may
2865 // have been redefined.
2866 bool trace_name_printed = false;
2867 adjust_default_methods(&trace_name_printed);
2868 if (verified_at_dump_time()) {
2869 // Initialize vtable and itable for classes which can be verified at dump time.
2870 // Unlinked classes such as old classes with major version < 50 cannot be verified
2871 // at dump time.
2872 vtable().initialize_vtable();
2873 itable().initialize_itable();
2874 }
2875 }
2876 #endif // INCLUDE_JVMTI
2877
2878 // restore constant pool resolved references
2879 constants()->restore_unshareable_info(CHECK);
2880
2881 if (array_klasses() != nullptr) {
2882 // To get a consistent list of classes we need MultiArray_lock to ensure
2883 // array classes aren't observed while they are being restored.
2884 RecursiveLocker rl(MultiArray_lock, THREAD);
2885 assert(this == array_klasses()->bottom_klass(), "sanity");
2886 // Array classes have null protection domain.
2887 // --> see ArrayKlass::complete_create_array_klass()
2888 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2889 }
2890
2891 // Initialize @ValueBased class annotation if not already set in the archived klass.
2892 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2893 set_is_value_based();
2894 }
2895 }
2896
2897 bool InstanceKlass::can_be_verified_at_dumptime() const {
2898 if (CDSConfig::preserve_all_dumptime_verification_states(this)) {
2899 return true;
2900 }
2901
2902 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2903 // This is a class that was dumped into the base archive, so we know
2904 // it was verified at dump time.
2905 return true;
2906 }
2907
2908 // Check if a class or any of its supertypes has a version older than 50.
2909 // CDS will not perform verification of old classes during dump time because
2910 // without changing the old verifier, the verification constraint cannot be
2911 // retrieved during dump time.
2912 // Verification of archived old classes will be performed during run time.
2913 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2914 return false;
2915 }
2916 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2917 return false;
2918 }
2919 Array<InstanceKlass*>* interfaces = local_interfaces();
2920 int len = interfaces->length();
2921 for (int i = 0; i < len; i++) {
2922 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2923 return false;
2924 }
2925 }
2926 return true;
2927 }
2928
2929 int InstanceKlass::shared_class_loader_type() const {
2930 if (is_shared_boot_class()) {
2931 return ClassLoader::BOOT_LOADER;
2932 } else if (is_shared_platform_class()) {
2933 return ClassLoader::PLATFORM_LOADER;
2934 } else if (is_shared_app_class()) {
2935 return ClassLoader::APP_LOADER;
2936 } else {
2937 return ClassLoader::OTHER;
2938 }
2939 }
2940
2941 #endif // INCLUDE_CDS
2942
2943 #if INCLUDE_JVMTI
2944 static void clear_all_breakpoints(Method* m) {
2945 m->clear_all_breakpoints();
2946 }
2947 #endif
2948
2949 void InstanceKlass::unload_class(InstanceKlass* ik) {
2950
2951 if (ik->is_scratch_class()) {
2952 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2953 return;
2954 }
2955 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2956
2957 // Release dependencies.
2958 ik->dependencies().remove_all_dependents();
2959
2960 // notify the debugger
2961 if (JvmtiExport::should_post_class_unload()) {
2962 JvmtiExport::post_class_unload(ik);
2963 }
2964
2965 // notify ClassLoadingService of class unload
2966 ClassLoadingService::notify_class_unloaded(ik);
2967
2968 SystemDictionaryShared::handle_class_unloading(ik);
2969
2970 if (log_is_enabled(Info, class, unload)) {
2971 ResourceMark rm;
2972 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2973 }
2974
2975 Events::log_class_unloading(Thread::current(), ik);
2976
2977 #if INCLUDE_JFR
2978 assert(ik != nullptr, "invariant");
2979 EventClassUnload event;
2980 event.set_unloadedClass(ik);
2981 event.set_definingClassLoader(ik->class_loader_data());
2982 event.commit();
2983 #endif
2984 }
2985
2986 static void method_release_C_heap_structures(Method* m) {
2987 m->release_C_heap_structures();
2988 }
2989
2990 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2991 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
2992 // Clean up C heap
2993 Klass::release_C_heap_structures();
2994
2995 // Deallocate and call destructors for MDO mutexes
2996 if (release_sub_metadata) {
2997 methods_do(method_release_C_heap_structures);
2998 }
2999
3000 // Deallocate oop map cache
3001 if (_oop_map_cache != nullptr) {
3002 delete _oop_map_cache;
3003 _oop_map_cache = nullptr;
3004 }
3005
3006 // Deallocate JNI identifiers for jfieldIDs
3007 JNIid::deallocate(jni_ids());
3008 set_jni_ids(nullptr);
3009
3010 jmethodID* jmeths = methods_jmethod_ids_acquire();
3011 if (jmeths != nullptr) {
3012 release_set_methods_jmethod_ids(nullptr);
3013 FreeHeap(jmeths);
3014 }
3015
3016 assert(_dep_context == nullptr,
3017 "dependencies should already be cleaned");
3018
3019 #if INCLUDE_JVMTI
3020 // Deallocate breakpoint records
3021 if (breakpoints() != nullptr) {
3022 methods_do(clear_all_breakpoints);
3023 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3024 }
3025
3026 // deallocate the cached class file
3027 if (_cached_class_file != nullptr) {
3028 os::free(_cached_class_file);
3029 _cached_class_file = nullptr;
3030 }
3031 #endif
3032
3033 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3034
3035 if (release_sub_metadata) {
3036 constants()->release_C_heap_structures();
3037 }
3038 }
3039
3040 // The constant pool is on stack if any of the methods are executing or
3041 // referenced by handles.
3042 bool InstanceKlass::on_stack() const {
3043 return _constants->on_stack();
3044 }
3045
3046 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3047 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3048 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3049
3050 // minor and major version numbers of class file
3051 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3052 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3053 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3054 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3055
3056 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3057 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3058 if (ik->constants()->version() == version) {
3059 return ik;
3060 }
3061 }
3062 return nullptr;
3063 }
3064
3065 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3066 if (array == nullptr) {
3067 _source_debug_extension = nullptr;
3068 } else {
3069 // Adding one to the attribute length in order to store a null terminator
3070 // character could cause an overflow because the attribute length is
3071 // already coded with an u4 in the classfile, but in practice, it's
3072 // unlikely to happen.
3073 assert((length+1) > length, "Overflow checking");
3074 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3075 for (int i = 0; i < length; i++) {
3076 sde[i] = array[i];
3077 }
3078 sde[length] = '\0';
3079 _source_debug_extension = sde;
3080 }
3081 }
3082
3083 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3084 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3085 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3086
3087 const char* InstanceKlass::signature_name() const {
3088
3089 // Get the internal name as a c string
3090 const char* src = (const char*) (name()->as_C_string());
3091 const int src_length = (int)strlen(src);
3092
3093 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3094
3095 // Add L as type indicator
3096 int dest_index = 0;
3097 dest[dest_index++] = JVM_SIGNATURE_CLASS;
3098
3099 // Add the actual class name
3100 for (int src_index = 0; src_index < src_length; ) {
3101 dest[dest_index++] = src[src_index++];
3102 }
3103
3104 if (is_hidden()) { // Replace the last '+' with a '.'.
3105 for (int index = (int)src_length; index > 0; index--) {
3106 if (dest[index] == '+') {
3107 dest[index] = JVM_SIGNATURE_DOT;
3108 break;
3109 }
3110 }
3111 }
3112
3113 // Add the semicolon and the null
3114 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3115 dest[dest_index] = '\0';
3116 return dest;
3117 }
3118
3119 ModuleEntry* InstanceKlass::module() const {
3120 if (is_hidden() &&
3121 in_unnamed_package() &&
3122 class_loader_data()->has_class_mirror_holder()) {
3123 // For a non-strong hidden class defined to an unnamed package,
3124 // its (class held) CLD will not have an unnamed module created for it.
3125 // Two choices to find the correct ModuleEntry:
3126 // 1. If hidden class is within a nest, use nest host's module
3127 // 2. Find the unnamed module off from the class loader
3128 // For now option #2 is used since a nest host is not set until
3129 // after the instance class is created in jvm_lookup_define_class().
3130 if (class_loader_data()->is_boot_class_loader_data()) {
3131 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3132 } else {
3133 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3134 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3135 return java_lang_Module::module_entry(module);
3136 }
3137 }
3138
3139 // Class is in a named package
3140 if (!in_unnamed_package()) {
3141 return _package_entry->module();
3142 }
3143
3144 // Class is in an unnamed package, return its loader's unnamed module
3145 return class_loader_data()->unnamed_module();
3146 }
3147
3148 bool InstanceKlass::in_javabase_module() const {
3149 return module()->name() == vmSymbols::java_base();
3150 }
3151
3152 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3153
3154 // ensure java/ packages only loaded by boot or platform builtin loaders
3155 // not needed for shared class since CDS does not archive prohibited classes.
3156 if (!is_shared()) {
3157 check_prohibited_package(name(), loader_data, CHECK);
3158 }
3159
3160 if (is_shared() && _package_entry != nullptr) {
3161 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3162 // we can use the saved package
3163 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3164 return;
3165 } else {
3166 _package_entry = nullptr;
3167 }
3168 }
3169
3170 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3171 // it returns, so we need to decrement it when the current function exits.
3172 TempNewSymbol from_class_name =
3173 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3174
3175 Symbol* pkg_name;
3176 if (pkg_entry != nullptr) {
3177 pkg_name = pkg_entry->name();
3178 } else {
3179 pkg_name = from_class_name;
3180 }
3181
3182 if (pkg_name != nullptr && loader_data != nullptr) {
3183
3184 // Find in class loader's package entry table.
3185 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3186
3187 // If the package name is not found in the loader's package
3188 // entry table, it is an indication that the package has not
3189 // been defined. Consider it defined within the unnamed module.
3190 if (_package_entry == nullptr) {
3191
3192 if (!ModuleEntryTable::javabase_defined()) {
3193 // Before java.base is defined during bootstrapping, define all packages in
3194 // the java.base module. If a non-java.base package is erroneously placed
3195 // in the java.base module it will be caught later when java.base
3196 // is defined by ModuleEntryTable::verify_javabase_packages check.
3197 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3198 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3199 } else {
3200 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3201 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3202 }
3203
3204 // A package should have been successfully created
3205 DEBUG_ONLY(ResourceMark rm(THREAD));
3206 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3207 name()->as_C_string(), loader_data->loader_name_and_id());
3208 }
3209
3210 if (log_is_enabled(Debug, module)) {
3211 ResourceMark rm(THREAD);
3212 ModuleEntry* m = _package_entry->module();
3213 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3214 external_name(),
3215 pkg_name->as_C_string(),
3216 loader_data->loader_name_and_id(),
3217 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3218 }
3219 } else {
3220 ResourceMark rm(THREAD);
3221 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3222 external_name(),
3223 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3224 UNNAMED_MODULE);
3225 }
3226 }
3227
3228 // Function set_classpath_index ensures that for a non-null _package_entry
3229 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3230 // It then sets the classpath_index in the package entry record.
3231 //
3232 // The classpath_index field is used to find the entry on the boot loader class
3233 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3234 // in an unnamed module. It is also used to indicate (for all packages whose
3235 // classes are loaded by the boot loader) that at least one of the package's
3236 // classes has been loaded.
3237 void InstanceKlass::set_classpath_index(s2 path_index) {
3238 if (_package_entry != nullptr) {
3239 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3240 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3241 assert(path_index != -1, "Unexpected classpath_index");
3242 _package_entry->set_classpath_index(path_index);
3243 }
3244 }
3245
3246 // different versions of is_same_class_package
3247
3248 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3249 oop classloader1 = this->class_loader();
3250 PackageEntry* classpkg1 = this->package();
3251 if (class2->is_objArray_klass()) {
3252 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3253 }
3254
3255 oop classloader2;
3256 PackageEntry* classpkg2;
3257 if (class2->is_instance_klass()) {
3258 classloader2 = class2->class_loader();
3259 classpkg2 = class2->package();
3260 } else {
3261 assert(class2->is_typeArray_klass(), "should be type array");
3262 classloader2 = nullptr;
3263 classpkg2 = nullptr;
3264 }
3265
3266 // Same package is determined by comparing class loader
3267 // and package entries. Both must be the same. This rule
3268 // applies even to classes that are defined in the unnamed
3269 // package, they still must have the same class loader.
3270 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3271 return true;
3272 }
3273
3274 return false;
3275 }
3276
3277 // return true if this class and other_class are in the same package. Classloader
3278 // and classname information is enough to determine a class's package
3279 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3280 const Symbol* other_class_name) const {
3281 if (class_loader() != other_class_loader) {
3282 return false;
3283 }
3284 if (name()->fast_compare(other_class_name) == 0) {
3285 return true;
3286 }
3287
3288 {
3289 ResourceMark rm;
3290
3291 bool bad_class_name = false;
3292 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3293 if (bad_class_name) {
3294 return false;
3295 }
3296 // Check that package_from_class_name() returns null, not "", if there is no package.
3297 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3298
3299 const Symbol* const this_package_name =
3300 this->package() != nullptr ? this->package()->name() : nullptr;
3301
3302 if (this_package_name == nullptr || other_pkg == nullptr) {
3303 // One of the two doesn't have a package. Only return true if the other
3304 // one also doesn't have a package.
3305 return this_package_name == other_pkg;
3306 }
3307
3308 // Check if package is identical
3309 return this_package_name->fast_compare(other_pkg) == 0;
3310 }
3311 }
3312
3313 static bool is_prohibited_package_slow(Symbol* class_name) {
3314 // Caller has ResourceMark
3315 int length;
3316 jchar* unicode = class_name->as_unicode(length);
3317 return (length >= 5 &&
3318 unicode[0] == 'j' &&
3319 unicode[1] == 'a' &&
3320 unicode[2] == 'v' &&
3321 unicode[3] == 'a' &&
3322 unicode[4] == '/');
3323 }
3324
3325 // Only boot and platform class loaders can define classes in "java/" packages.
3326 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3327 ClassLoaderData* loader_data,
3328 TRAPS) {
3329 if (!loader_data->is_boot_class_loader_data() &&
3330 !loader_data->is_platform_class_loader_data() &&
3331 class_name != nullptr && class_name->utf8_length() >= 5) {
3332 ResourceMark rm(THREAD);
3333 bool prohibited;
3334 const u1* base = class_name->base();
3335 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3336 prohibited = is_prohibited_package_slow(class_name);
3337 } else {
3338 char* name = class_name->as_C_string();
3339 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3340 }
3341 if (prohibited) {
3342 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3343 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3344 char* name = pkg_name->as_C_string();
3345 const char* class_loader_name = loader_data->loader_name_and_id();
3346 StringUtils::replace_no_expand(name, "/", ".");
3347 const char* msg_text1 = "Class loader (instance of): ";
3348 const char* msg_text2 = " tried to load prohibited package name: ";
3349 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3350 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3351 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3352 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3353 }
3354 }
3355 return;
3356 }
3357
3358 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3359 constantPoolHandle i_cp(THREAD, constants());
3360 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3361 int ioff = iter.inner_class_info_index();
3362 if (ioff != 0) {
3363 // Check to see if the name matches the class we're looking for
3364 // before attempting to find the class.
3365 if (i_cp->klass_name_at_matches(this, ioff)) {
3366 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3367 if (this == inner_klass) {
3368 *ooff = iter.outer_class_info_index();
3369 *noff = iter.inner_name_index();
3370 return true;
3371 }
3372 }
3373 }
3374 }
3375 return false;
3376 }
3377
3378 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3379 InstanceKlass* outer_klass = nullptr;
3380 *inner_is_member = false;
3381 int ooff = 0, noff = 0;
3382 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3383 if (has_inner_classes_attr) {
3384 constantPoolHandle i_cp(THREAD, constants());
3385 if (ooff != 0) {
3386 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3387 if (!ok->is_instance_klass()) {
3388 // If the outer class is not an instance klass then it cannot have
3389 // declared any inner classes.
3390 ResourceMark rm(THREAD);
3391 // Names are all known to be < 64k so we know this formatted message is not excessively large.
3392 Exceptions::fthrow(
3393 THREAD_AND_LOCATION,
3394 vmSymbols::java_lang_IncompatibleClassChangeError(),
3395 "%s and %s disagree on InnerClasses attribute",
3396 ok->external_name(),
3397 external_name());
3398 return nullptr;
3399 }
3400 outer_klass = InstanceKlass::cast(ok);
3401 *inner_is_member = true;
3402 }
3403 if (nullptr == outer_klass) {
3404 // It may be a local class; try for that.
3405 int encl_method_class_idx = enclosing_method_class_index();
3406 if (encl_method_class_idx != 0) {
3407 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3408 outer_klass = InstanceKlass::cast(ok);
3409 *inner_is_member = false;
3410 }
3411 }
3412 }
3413
3414 // If no inner class attribute found for this class.
3415 if (nullptr == outer_klass) return nullptr;
3416
3417 // Throws an exception if outer klass has not declared k as an inner klass
3418 // We need evidence that each klass knows about the other, or else
3419 // the system could allow a spoof of an inner class to gain access rights.
3420 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3421 return outer_klass;
3422 }
3423
3424 u2 InstanceKlass::compute_modifier_flags() const {
3425 u2 access = access_flags().as_unsigned_short();
3426
3427 // But check if it happens to be member class.
3428 InnerClassesIterator iter(this);
3429 for (; !iter.done(); iter.next()) {
3430 int ioff = iter.inner_class_info_index();
3431 // Inner class attribute can be zero, skip it.
3432 // Strange but true: JVM spec. allows null inner class refs.
3433 if (ioff == 0) continue;
3434
3435 // only look at classes that are already loaded
3436 // since we are looking for the flags for our self.
3437 Symbol* inner_name = constants()->klass_name_at(ioff);
3438 if (name() == inner_name) {
3439 // This is really a member class.
3440 access = iter.inner_access_flags();
3441 break;
3442 }
3443 }
3444 // Remember to strip ACC_SUPER bit
3445 return (access & (~JVM_ACC_SUPER));
3446 }
3447
3448 jint InstanceKlass::jvmti_class_status() const {
3449 jint result = 0;
3450
3451 if (is_linked()) {
3452 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3453 }
3454
3455 if (is_initialized()) {
3456 assert(is_linked(), "Class status is not consistent");
3457 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3458 }
3459 if (is_in_error_state()) {
3460 result |= JVMTI_CLASS_STATUS_ERROR;
3461 }
3462 return result;
3463 }
3464
3465 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3466 bool implements_interface; // initialized by method_at_itable_or_null
3467 Method* m = method_at_itable_or_null(holder, index,
3468 implements_interface); // out parameter
3469 if (m != nullptr) {
3470 assert(implements_interface, "sanity");
3471 return m;
3472 } else if (implements_interface) {
3473 // Throw AbstractMethodError since corresponding itable slot is empty.
3474 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3475 } else {
3476 // If the interface isn't implemented by the receiver class,
3477 // the VM should throw IncompatibleClassChangeError.
3478 ResourceMark rm(THREAD);
3479 stringStream ss;
3480 bool same_module = (module() == holder->module());
3481 ss.print("Receiver class %s does not implement "
3482 "the interface %s defining the method to be called "
3483 "(%s%s%s)",
3484 external_name(), holder->external_name(),
3485 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3486 (same_module) ? "" : "; ",
3487 (same_module) ? "" : holder->class_in_module_of_loader());
3488 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3489 }
3490 }
3491
3492 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3493 klassItable itable(this);
3494 for (int i = 0; i < itable.size_offset_table(); i++) {
3495 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3496 if (offset_entry->interface_klass() == holder) {
3497 implements_interface = true;
3498 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3499 Method* m = ime[index].method();
3500 return m;
3501 }
3502 }
3503 implements_interface = false;
3504 return nullptr; // offset entry not found
3505 }
3506
3507 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3508 assert(is_linked(), "required");
3509 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3510 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3511
3512 int vtable_index = Method::invalid_vtable_index;
3513 Symbol* name = intf_method->name();
3514 Symbol* signature = intf_method->signature();
3515
3516 // First check in default method array
3517 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3518 int index = find_method_index(default_methods(),
3519 name, signature,
3520 Klass::OverpassLookupMode::find,
3521 Klass::StaticLookupMode::find,
3522 Klass::PrivateLookupMode::find);
3523 if (index >= 0) {
3524 vtable_index = default_vtable_indices()->at(index);
3525 }
3526 }
3527 if (vtable_index == Method::invalid_vtable_index) {
3528 // get vtable_index for miranda methods
3529 klassVtable vt = vtable();
3530 vtable_index = vt.index_of_miranda(name, signature);
3531 }
3532 return vtable_index;
3533 }
3534
3535 #if INCLUDE_JVMTI
3536 // update default_methods for redefineclasses for methods that are
3537 // not yet in the vtable due to concurrent subclass define and superinterface
3538 // redefinition
3539 // Note: those in the vtable, should have been updated via adjust_method_entries
3540 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3541 // search the default_methods for uses of either obsolete or EMCP methods
3542 if (default_methods() != nullptr) {
3543 for (int index = 0; index < default_methods()->length(); index ++) {
3544 Method* old_method = default_methods()->at(index);
3545 if (old_method == nullptr || !old_method->is_old()) {
3546 continue; // skip uninteresting entries
3547 }
3548 assert(!old_method->is_deleted(), "default methods may not be deleted");
3549 Method* new_method = old_method->get_new_method();
3550 default_methods()->at_put(index, new_method);
3551
3552 if (log_is_enabled(Info, redefine, class, update)) {
3553 ResourceMark rm;
3554 if (!(*trace_name_printed)) {
3555 log_info(redefine, class, update)
3556 ("adjust: klassname=%s default methods from name=%s",
3557 external_name(), old_method->method_holder()->external_name());
3558 *trace_name_printed = true;
3559 }
3560 log_debug(redefine, class, update, vtables)
3561 ("default method update: %s(%s) ",
3562 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3563 }
3564 }
3565 }
3566 }
3567 #endif // INCLUDE_JVMTI
3568
3569 // On-stack replacement stuff
3570 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3571 assert_lock_strong(NMethodState_lock);
3572 #ifndef PRODUCT
3573 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3574 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3575 "redundant OSR recompilation detected. memory leak in CodeCache!");
3576 #endif
3577 // only one compilation can be active
3578 assert(n->is_osr_method(), "wrong kind of nmethod");
3579 n->set_osr_link(osr_nmethods_head());
3580 set_osr_nmethods_head(n);
3581 // Raise the highest osr level if necessary
3582 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3583
3584 // Get rid of the osr methods for the same bci that have lower levels.
3585 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3586 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3587 if (inv != nullptr && inv->is_in_use()) {
3588 inv->make_not_entrant();
3589 }
3590 }
3591 }
3592
3593 // Remove osr nmethod from the list. Return true if found and removed.
3594 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3595 // This is a short non-blocking critical region, so the no safepoint check is ok.
3596 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3597 assert(n->is_osr_method(), "wrong kind of nmethod");
3598 nmethod* last = nullptr;
3599 nmethod* cur = osr_nmethods_head();
3600 int max_level = CompLevel_none; // Find the max comp level excluding n
3601 Method* m = n->method();
3602 // Search for match
3603 bool found = false;
3604 while(cur != nullptr && cur != n) {
3605 if (m == cur->method()) {
3606 // Find max level before n
3607 max_level = MAX2(max_level, cur->comp_level());
3608 }
3609 last = cur;
3610 cur = cur->osr_link();
3611 }
3612 nmethod* next = nullptr;
3613 if (cur == n) {
3614 found = true;
3615 next = cur->osr_link();
3616 if (last == nullptr) {
3617 // Remove first element
3618 set_osr_nmethods_head(next);
3619 } else {
3620 last->set_osr_link(next);
3621 }
3622 }
3623 n->set_osr_link(nullptr);
3624 cur = next;
3625 while (cur != nullptr) {
3626 // Find max level after n
3627 if (m == cur->method()) {
3628 max_level = MAX2(max_level, cur->comp_level());
3629 }
3630 cur = cur->osr_link();
3631 }
3632 m->set_highest_osr_comp_level(max_level);
3633 return found;
3634 }
3635
3636 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3637 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3638 nmethod* osr = osr_nmethods_head();
3639 int found = 0;
3640 while (osr != nullptr) {
3641 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3642 if (osr->method() == m) {
3643 deopt_scope->mark(osr);
3644 found++;
3645 }
3646 osr = osr->osr_link();
3647 }
3648 return found;
3649 }
3650
3651 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3652 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3653 nmethod* osr = osr_nmethods_head();
3654 nmethod* best = nullptr;
3655 while (osr != nullptr) {
3656 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3657 // There can be a time when a c1 osr method exists but we are waiting
3658 // for a c2 version. When c2 completes its osr nmethod we will trash
3659 // the c1 version and only be able to find the c2 version. However
3660 // while we overflow in the c1 code at back branches we don't want to
3661 // try and switch to the same code as we are already running
3662
3663 if (osr->method() == m &&
3664 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3665 if (match_level) {
3666 if (osr->comp_level() == comp_level) {
3667 // Found a match - return it.
3668 return osr;
3669 }
3670 } else {
3671 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3672 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3673 // Found the best possible - return it.
3674 return osr;
3675 }
3676 best = osr;
3677 }
3678 }
3679 }
3680 osr = osr->osr_link();
3681 }
3682
3683 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3684 if (best != nullptr && best->comp_level() >= comp_level) {
3685 return best;
3686 }
3687 return nullptr;
3688 }
3689
3690 // -----------------------------------------------------------------------------------------------------
3691 // Printing
3692
3693 #define BULLET " - "
3694
3695 static const char* state_names[] = {
3696 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3697 };
3698
3699 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3700 for (int i = 0; i < len; i++) {
3701 intptr_t e = start[i];
3702 st->print("%d : " INTPTR_FORMAT, i, e);
3703 if (MetaspaceObj::is_valid((Metadata*)e)) {
3704 st->print(" ");
3705 ((Metadata*)e)->print_value_on(st);
3706 }
3707 st->cr();
3708 }
3709 }
3710
3711 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3712 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3713 }
3714
3715 const char* InstanceKlass::init_state_name() const {
3716 return state_names[init_state()];
3717 }
3718
3719 const char* InstanceKlass::state2name(ClassState s) {
3720 return state_names[s];
3721 }
3722
3723 void InstanceKlass::print_on(outputStream* st) const {
3724 assert(is_klass(), "must be klass");
3725 Klass::print_on(st);
3726
3727 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3728 st->print(BULLET"klass size: %d", size()); st->cr();
3729 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3730 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3731 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3732 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3733 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3734 st->print(BULLET"sub: ");
3735 Klass* sub = subklass();
3736 int n;
3737 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3738 if (n < MaxSubklassPrintSize) {
3739 sub->print_value_on(st);
3740 st->print(" ");
3741 }
3742 }
3743 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize);
3744 st->cr();
3745
3746 if (is_interface()) {
3747 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3748 if (nof_implementors() == 1) {
3749 st->print_cr(BULLET"implementor: ");
3750 st->print(" ");
3751 implementor()->print_value_on(st);
3752 st->cr();
3753 }
3754 }
3755
3756 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3757 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3758 if (Verbose || WizardMode) {
3759 Array<Method*>* method_array = methods();
3760 for (int i = 0; i < method_array->length(); i++) {
3761 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3762 }
3763 }
3764 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3765 if (default_methods() != nullptr) {
3766 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3767 if (Verbose) {
3768 Array<Method*>* method_array = default_methods();
3769 for (int i = 0; i < method_array->length(); i++) {
3770 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3771 }
3772 }
3773 }
3774 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3775 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3776 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3777
3778 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3779
3780 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3781 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3782
3783 if (secondary_supers() != nullptr) {
3784 if (Verbose) {
3785 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3786 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3787 for (int i = 0; i < _secondary_supers->length(); i++) {
3788 ResourceMark rm; // for external_name()
3789 Klass* secondary_super = _secondary_supers->at(i);
3790 st->print(BULLET"%2d:", i);
3791 if (is_hashed) {
3792 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3793 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3794 st->print(" dist:%02d:", distance);
3795 }
3796 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3797 }
3798 }
3799 }
3800 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3801
3802 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3803 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3804 if (source_debug_extension() != nullptr) {
3805 st->print(BULLET"source debug extension: ");
3806 st->print("%s", source_debug_extension());
3807 st->cr();
3808 }
3809 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3810 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3811 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3812 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3813 {
3814 bool have_pv = false;
3815 // previous versions are linked together through the InstanceKlass
3816 for (InstanceKlass* pv_node = previous_versions();
3817 pv_node != nullptr;
3818 pv_node = pv_node->previous_versions()) {
3819 if (!have_pv)
3820 st->print(BULLET"previous version: ");
3821 have_pv = true;
3822 pv_node->constants()->print_value_on(st);
3823 }
3824 if (have_pv) st->cr();
3825 }
3826
3827 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3828 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3829 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3830 print_on_maybe_null(st, BULLET"record components: ", record_components());
3831 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3832 if (java_mirror() != nullptr) {
3833 st->print(BULLET"java mirror: ");
3834 java_mirror()->print_value_on(st);
3835 st->cr();
3836 } else {
3837 st->print_cr(BULLET"java mirror: null");
3838 }
3839 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3840 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3841 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3842 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3843 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3844
3845 FieldPrinter print_static_field(st);
3846 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3847 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3848 FieldPrinter print_nonstatic_field(st);
3849 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3850 ik->print_nonstatic_fields(&print_nonstatic_field);
3851
3852 st->print(BULLET"non-static oop maps: ");
3853 OopMapBlock* map = start_of_nonstatic_oop_maps();
3854 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3855 while (map < end_map) {
3856 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3857 map++;
3858 }
3859 st->cr();
3860 }
3861
3862 void InstanceKlass::print_value_on(outputStream* st) const {
3863 assert(is_klass(), "must be klass");
3864 if (Verbose || WizardMode) access_flags().print_on(st);
3865 name()->print_value_on(st);
3866 }
3867
3868 void FieldPrinter::do_field(fieldDescriptor* fd) {
3869 _st->print(BULLET);
3870 if (_obj == nullptr) {
3871 fd->print_on(_st);
3872 _st->cr();
3873 } else {
3874 fd->print_on_for(_st, _obj);
3875 _st->cr();
3876 }
3877 }
3878
3879
3880 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3881 Klass::oop_print_on(obj, st);
3882
3883 if (this == vmClasses::String_klass()) {
3884 typeArrayOop value = java_lang_String::value(obj);
3885 juint length = java_lang_String::length(obj);
3886 if (value != nullptr &&
3887 value->is_typeArray() &&
3888 length <= (juint) value->length()) {
3889 st->print(BULLET"string: ");
3890 java_lang_String::print(obj, st);
3891 st->cr();
3892 }
3893 }
3894
3895 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3896 FieldPrinter print_field(st, obj);
3897 print_nonstatic_fields(&print_field);
3898
3899 if (this == vmClasses::Class_klass()) {
3900 st->print(BULLET"signature: ");
3901 java_lang_Class::print_signature(obj, st);
3902 st->cr();
3903 Klass* real_klass = java_lang_Class::as_Klass(obj);
3904 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3905 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3906 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3907 }
3908 } else if (this == vmClasses::MethodType_klass()) {
3909 st->print(BULLET"signature: ");
3910 java_lang_invoke_MethodType::print_signature(obj, st);
3911 st->cr();
3912 }
3913 }
3914
3915 #ifndef PRODUCT
3916
3917 bool InstanceKlass::verify_itable_index(int i) {
3918 int method_count = klassItable::method_count_for_interface(this);
3919 assert(i >= 0 && i < method_count, "index out of bounds");
3920 return true;
3921 }
3922
3923 #endif //PRODUCT
3924
3925 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3926 st->print("a ");
3927 name()->print_value_on(st);
3928 obj->print_address_on(st);
3929 if (this == vmClasses::String_klass()
3930 && java_lang_String::value(obj) != nullptr) {
3931 ResourceMark rm;
3932 int len = java_lang_String::length(obj);
3933 int plen = (len < 24 ? len : 12);
3934 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3935 st->print(" = \"%s\"", str);
3936 if (len > plen)
3937 st->print("...[%d]", len);
3938 } else if (this == vmClasses::Class_klass()) {
3939 Klass* k = java_lang_Class::as_Klass(obj);
3940 st->print(" = ");
3941 if (k != nullptr) {
3942 k->print_value_on(st);
3943 } else {
3944 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3945 st->print("%s", tname ? tname : "type?");
3946 }
3947 } else if (this == vmClasses::MethodType_klass()) {
3948 st->print(" = ");
3949 java_lang_invoke_MethodType::print_signature(obj, st);
3950 } else if (java_lang_boxing_object::is_instance(obj)) {
3951 st->print(" = ");
3952 java_lang_boxing_object::print(obj, st);
3953 } else if (this == vmClasses::LambdaForm_klass()) {
3954 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3955 if (vmentry != nullptr) {
3956 st->print(" => ");
3957 vmentry->print_value_on(st);
3958 }
3959 } else if (this == vmClasses::MemberName_klass()) {
3960 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3961 if (vmtarget != nullptr) {
3962 st->print(" = ");
3963 vmtarget->print_value_on(st);
3964 } else {
3965 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3966 oop name = java_lang_invoke_MemberName::name(obj);
3967 if (clazz != nullptr) {
3968 clazz->print_value_on(st);
3969 } else {
3970 st->print("null");
3971 }
3972 st->print(".");
3973 if (name != nullptr) {
3974 name->print_value_on(st);
3975 } else {
3976 st->print("null");
3977 }
3978 }
3979 }
3980 }
3981
3982 const char* InstanceKlass::internal_name() const {
3983 return external_name();
3984 }
3985
3986 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3987 const ModuleEntry* module_entry,
3988 const ClassFileStream* cfs) const {
3989
3990 if (ClassListWriter::is_enabled()) {
3991 ClassListWriter::write(this, cfs);
3992 }
3993
3994 print_class_load_helper(loader_data, module_entry, cfs);
3995 print_class_load_cause_logging();
3996 }
3997
3998 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
3999 const ModuleEntry* module_entry,
4000 const ClassFileStream* cfs) const {
4001
4002 if (!log_is_enabled(Info, class, load)) {
4003 return;
4004 }
4005
4006 ResourceMark rm;
4007 LogMessage(class, load) msg;
4008 stringStream info_stream;
4009
4010 // Name and class hierarchy info
4011 info_stream.print("%s", external_name());
4012
4013 // Source
4014 if (cfs != nullptr) {
4015 if (cfs->source() != nullptr) {
4016 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4017 if (module_name != nullptr) {
4018 // When the boot loader created the stream, it didn't know the module name
4019 // yet. Let's format it now.
4020 if (cfs->from_boot_loader_modules_image()) {
4021 info_stream.print(" source: jrt:/%s", module_name);
4022 } else {
4023 info_stream.print(" source: %s", cfs->source());
4024 }
4025 } else {
4026 info_stream.print(" source: %s", cfs->source());
4027 }
4028 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4029 Thread* current = Thread::current();
4030 Klass* caller = current->is_Java_thread() ?
4031 JavaThread::cast(current)->security_get_caller_class(1):
4032 nullptr;
4033 // caller can be null, for example, during a JVMTI VM_Init hook
4034 if (caller != nullptr) {
4035 info_stream.print(" source: instance of %s", caller->external_name());
4036 } else {
4037 // source is unknown
4038 }
4039 } else {
4040 oop class_loader = loader_data->class_loader();
4041 info_stream.print(" source: %s", class_loader->klass()->external_name());
4042 }
4043 } else {
4044 assert(this->is_shared(), "must be");
4045 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4046 info_stream.print(" source: shared objects file (top)");
4047 } else {
4048 info_stream.print(" source: shared objects file");
4049 }
4050 }
4051
4052 info_stream.print(" loader:");
4053 if (is_shared()) {
4054 info_stream.print(" %s", SystemDictionaryShared::class_loader_name_for_shared((Klass*)this));
4055 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4056 info_stream.print(" boot_loader");
4057 } else {
4058 oop class_loader = loader_data->class_loader();
4059 if (class_loader != nullptr) {
4060 info_stream.print(" %s", class_loader->klass()->external_name());
4061 oop cl_name_and_id = java_lang_ClassLoader::nameAndId(class_loader);
4062 if (cl_name_and_id != nullptr) {
4063 info_stream.print(" %s", java_lang_String::as_utf8_string(cl_name_and_id));
4064 }
4065 } else {
4066 info_stream.print(" null");
4067 }
4068 }
4069 msg.info("%s", info_stream.as_string());
4070
4071 if (log_is_enabled(Debug, class, load)) {
4072 stringStream debug_stream;
4073
4074 // Class hierarchy info
4075 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4076 p2i(this), p2i(superklass()));
4077
4078 // Interfaces
4079 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4080 debug_stream.print(" interfaces:");
4081 int length = local_interfaces()->length();
4082 for (int i = 0; i < length; i++) {
4083 debug_stream.print(" " PTR_FORMAT,
4084 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4085 }
4086 }
4087
4088 // Class loader
4089 debug_stream.print(" loader: [");
4090 loader_data->print_value_on(&debug_stream);
4091 debug_stream.print("]");
4092
4093 // Classfile checksum
4094 if (cfs) {
4095 debug_stream.print(" bytes: %d checksum: %08x",
4096 cfs->length(),
4097 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4098 cfs->length()));
4099 }
4100
4101 msg.debug("%s", debug_stream.as_string());
4102 }
4103 }
4104
4105 void InstanceKlass::print_class_load_cause_logging() const {
4106 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4107 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4108 JavaThread* current = JavaThread::current();
4109 ResourceMark rm(current);
4110 const char* name = external_name();
4111
4112 if (LogClassLoadingCauseFor == nullptr ||
4113 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4114 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4115 return;
4116 }
4117
4118 // Log Java stack first
4119 {
4120 LogMessage(class, load, cause) msg;
4121 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4122
4123 info_stream.print_cr("Java stack when loading %s:", name);
4124 current->print_stack_on(&info_stream);
4125 }
4126
4127 // Log native stack second
4128 if (log_cause_native) {
4129 // Log to string first so that lines can be indented
4130 stringStream stack_stream;
4131 char buf[O_BUFLEN];
4132 address lastpc = nullptr;
4133 NativeStackPrinter nsp(current);
4134 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc,
4135 true /* print_source_info */, -1 /* max stack */);
4136
4137 LogMessage(class, load, cause, native) msg;
4138 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4139 info_stream.print_cr("Native stack when loading %s:", name);
4140
4141 // Print each native stack line to the log
4142 int size = (int) stack_stream.size();
4143 char* stack = stack_stream.as_string();
4144 char* stack_end = stack + size;
4145 char* line_start = stack;
4146 for (char* p = stack; p < stack_end; p++) {
4147 if (*p == '\n') {
4148 *p = '\0';
4149 info_stream.print_cr("\t%s", line_start);
4150 line_start = p + 1;
4151 }
4152 }
4153 if (line_start < stack_end) {
4154 info_stream.print_cr("\t%s", line_start);
4155 }
4156 }
4157 }
4158 }
4159
4160 // Verification
4161
4162 class VerifyFieldClosure: public BasicOopIterateClosure {
4163 protected:
4164 template <class T> void do_oop_work(T* p) {
4165 oop obj = RawAccess<>::oop_load(p);
4166 if (!oopDesc::is_oop_or_null(obj)) {
4167 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4168 Universe::print_on(tty);
4169 guarantee(false, "boom");
4170 }
4171 }
4172 public:
4173 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4174 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4175 };
4176
4177 void InstanceKlass::verify_on(outputStream* st) {
4178 #ifndef PRODUCT
4179 // Avoid redundant verifies, this really should be in product.
4180 if (_verify_count == Universe::verify_count()) return;
4181 _verify_count = Universe::verify_count();
4182 #endif
4183
4184 // Verify Klass
4185 Klass::verify_on(st);
4186
4187 // Verify that klass is present in ClassLoaderData
4188 guarantee(class_loader_data()->contains_klass(this),
4189 "this class isn't found in class loader data");
4190
4191 // Verify vtables
4192 if (is_linked()) {
4193 // $$$ This used to be done only for m/s collections. Doing it
4194 // always seemed a valid generalization. (DLD -- 6/00)
4195 vtable().verify(st);
4196 }
4197
4198 // Verify first subklass
4199 if (subklass() != nullptr) {
4200 guarantee(subklass()->is_klass(), "should be klass");
4201 }
4202
4203 // Verify siblings
4204 Klass* super = this->super();
4205 Klass* sib = next_sibling();
4206 if (sib != nullptr) {
4207 if (sib == this) {
4208 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4209 }
4210
4211 guarantee(sib->is_klass(), "should be klass");
4212 guarantee(sib->super() == super, "siblings should have same superklass");
4213 }
4214
4215 // Verify local interfaces
4216 if (local_interfaces()) {
4217 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4218 for (int j = 0; j < local_interfaces->length(); j++) {
4219 InstanceKlass* e = local_interfaces->at(j);
4220 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4221 }
4222 }
4223
4224 // Verify transitive interfaces
4225 if (transitive_interfaces() != nullptr) {
4226 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4227 for (int j = 0; j < transitive_interfaces->length(); j++) {
4228 InstanceKlass* e = transitive_interfaces->at(j);
4229 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4230 }
4231 }
4232
4233 // Verify methods
4234 if (methods() != nullptr) {
4235 Array<Method*>* methods = this->methods();
4236 for (int j = 0; j < methods->length(); j++) {
4237 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4238 }
4239 for (int j = 0; j < methods->length() - 1; j++) {
4240 Method* m1 = methods->at(j);
4241 Method* m2 = methods->at(j + 1);
4242 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4243 }
4244 }
4245
4246 // Verify method ordering
4247 if (method_ordering() != nullptr) {
4248 Array<int>* method_ordering = this->method_ordering();
4249 int length = method_ordering->length();
4250 if (JvmtiExport::can_maintain_original_method_order() ||
4251 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4252 guarantee(length == methods()->length(), "invalid method ordering length");
4253 jlong sum = 0;
4254 for (int j = 0; j < length; j++) {
4255 int original_index = method_ordering->at(j);
4256 guarantee(original_index >= 0, "invalid method ordering index");
4257 guarantee(original_index < length, "invalid method ordering index");
4258 sum += original_index;
4259 }
4260 // Verify sum of indices 0,1,...,length-1
4261 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4262 } else {
4263 guarantee(length == 0, "invalid method ordering length");
4264 }
4265 }
4266
4267 // Verify default methods
4268 if (default_methods() != nullptr) {
4269 Array<Method*>* methods = this->default_methods();
4270 for (int j = 0; j < methods->length(); j++) {
4271 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4272 }
4273 for (int j = 0; j < methods->length() - 1; j++) {
4274 Method* m1 = methods->at(j);
4275 Method* m2 = methods->at(j + 1);
4276 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4277 }
4278 }
4279
4280 // Verify JNI static field identifiers
4281 if (jni_ids() != nullptr) {
4282 jni_ids()->verify(this);
4283 }
4284
4285 // Verify other fields
4286 if (constants() != nullptr) {
4287 guarantee(constants()->is_constantPool(), "should be constant pool");
4288 }
4289 }
4290
4291 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4292 Klass::oop_verify_on(obj, st);
4293 VerifyFieldClosure blk;
4294 obj->oop_iterate(&blk);
4295 }
4296
4297
4298 // JNIid class for jfieldIDs only
4299 // Note to reviewers:
4300 // These JNI functions are just moved over to column 1 and not changed
4301 // in the compressed oops workspace.
4302 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4303 _holder = holder;
4304 _offset = offset;
4305 _next = next;
4306 debug_only(_is_static_field_id = false;)
4307 }
4308
4309
4310 JNIid* JNIid::find(int offset) {
4311 JNIid* current = this;
4312 while (current != nullptr) {
4313 if (current->offset() == offset) return current;
4314 current = current->next();
4315 }
4316 return nullptr;
4317 }
4318
4319 void JNIid::deallocate(JNIid* current) {
4320 while (current != nullptr) {
4321 JNIid* next = current->next();
4322 delete current;
4323 current = next;
4324 }
4325 }
4326
4327
4328 void JNIid::verify(Klass* holder) {
4329 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4330 int end_field_offset;
4331 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4332
4333 JNIid* current = this;
4334 while (current != nullptr) {
4335 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4336 #ifdef ASSERT
4337 int o = current->offset();
4338 if (current->is_static_field_id()) {
4339 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4340 }
4341 #endif
4342 current = current->next();
4343 }
4344 }
4345
4346 void InstanceKlass::set_init_state(ClassState state) {
4347 #ifdef ASSERT
4348 bool good_state = is_shared() ? (_init_state <= state)
4349 : (_init_state < state);
4350 assert(good_state || state == allocated, "illegal state transition");
4351 #endif
4352 assert(_init_thread == nullptr, "should be cleared before state change");
4353 Atomic::release_store(&_init_state, state);
4354 }
4355
4356 #if INCLUDE_JVMTI
4357
4358 // RedefineClasses() support for previous versions
4359
4360 // Globally, there is at least one previous version of a class to walk
4361 // during class unloading, which is saved because old methods in the class
4362 // are still running. Otherwise the previous version list is cleaned up.
4363 bool InstanceKlass::_should_clean_previous_versions = false;
4364
4365 // Returns true if there are previous versions of a class for class
4366 // unloading only. Also resets the flag to false. purge_previous_version
4367 // will set the flag to true if there are any left, i.e., if there's any
4368 // work to do for next time. This is to avoid the expensive code cache
4369 // walk in CLDG::clean_deallocate_lists().
4370 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4371 bool ret = _should_clean_previous_versions;
4372 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4373 ret ? "true" : "false");
4374 _should_clean_previous_versions = false;
4375 return ret;
4376 }
4377
4378 // This nulls out jmethodIDs for all methods in 'klass'
4379 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4380 // during class unloading.
4381 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4382 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4383 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4384 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4385 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4386 Array<Method*>* method_refs = klass->methods();
4387 for (int k = 0; k < method_refs->length(); k++) {
4388 Method* method = method_refs->at(k);
4389 if (method != nullptr && method->is_obsolete()) {
4390 method->clear_jmethod_id();
4391 }
4392 }
4393 }
4394
4395 // Purge previous versions before adding new previous versions of the class and
4396 // during class unloading.
4397 void InstanceKlass::purge_previous_version_list() {
4398 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4399 assert(has_been_redefined(), "Should only be called for main class");
4400
4401 // Quick exit.
4402 if (previous_versions() == nullptr) {
4403 return;
4404 }
4405
4406 // This klass has previous versions so see what we can cleanup
4407 // while it is safe to do so.
4408
4409 int deleted_count = 0; // leave debugging breadcrumbs
4410 int live_count = 0;
4411 ClassLoaderData* loader_data = class_loader_data();
4412 assert(loader_data != nullptr, "should never be null");
4413
4414 ResourceMark rm;
4415 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4416
4417 // previous versions are linked together through the InstanceKlass
4418 InstanceKlass* pv_node = previous_versions();
4419 InstanceKlass* last = this;
4420 int version = 0;
4421
4422 // check the previous versions list
4423 for (; pv_node != nullptr; ) {
4424
4425 ConstantPool* pvcp = pv_node->constants();
4426 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4427
4428 if (!pvcp->on_stack()) {
4429 // If the constant pool isn't on stack, none of the methods
4430 // are executing. Unlink this previous_version.
4431 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4432 // so will be deallocated during the next phase of class unloading.
4433 log_trace(redefine, class, iklass, purge)
4434 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4435 // Unlink from previous version list.
4436 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4437 InstanceKlass* next = pv_node->previous_versions();
4438 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4439 pv_node->link_previous_versions(nullptr); // point next to null
4440 last->link_previous_versions(next);
4441 // Delete this node directly. Nothing is referring to it and we don't
4442 // want it to increase the counter for metadata to delete in CLDG.
4443 MetadataFactory::free_metadata(loader_data, pv_node);
4444 pv_node = next;
4445 deleted_count++;
4446 version++;
4447 continue;
4448 } else {
4449 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4450 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4451 live_count++;
4452 if (pvcp->is_shared()) {
4453 // Shared previous versions can never be removed so no cleaning is needed.
4454 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4455 } else {
4456 // Previous version alive, set that clean is needed for next time.
4457 _should_clean_previous_versions = true;
4458 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4459 }
4460 }
4461
4462 // next previous version
4463 last = pv_node;
4464 pv_node = pv_node->previous_versions();
4465 version++;
4466 }
4467 log_trace(redefine, class, iklass, purge)
4468 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4469 }
4470
4471 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4472 int emcp_method_count) {
4473 int obsolete_method_count = old_methods->length() - emcp_method_count;
4474
4475 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4476 _previous_versions != nullptr) {
4477 // We have a mix of obsolete and EMCP methods so we have to
4478 // clear out any matching EMCP method entries the hard way.
4479 int local_count = 0;
4480 for (int i = 0; i < old_methods->length(); i++) {
4481 Method* old_method = old_methods->at(i);
4482 if (old_method->is_obsolete()) {
4483 // only obsolete methods are interesting
4484 Symbol* m_name = old_method->name();
4485 Symbol* m_signature = old_method->signature();
4486
4487 // previous versions are linked together through the InstanceKlass
4488 int j = 0;
4489 for (InstanceKlass* prev_version = _previous_versions;
4490 prev_version != nullptr;
4491 prev_version = prev_version->previous_versions(), j++) {
4492
4493 Array<Method*>* method_refs = prev_version->methods();
4494 for (int k = 0; k < method_refs->length(); k++) {
4495 Method* method = method_refs->at(k);
4496
4497 if (!method->is_obsolete() &&
4498 method->name() == m_name &&
4499 method->signature() == m_signature) {
4500 // The current RedefineClasses() call has made all EMCP
4501 // versions of this method obsolete so mark it as obsolete
4502 log_trace(redefine, class, iklass, add)
4503 ("%s(%s): flush obsolete method @%d in version @%d",
4504 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4505
4506 method->set_is_obsolete();
4507 break;
4508 }
4509 }
4510
4511 // The previous loop may not find a matching EMCP method, but
4512 // that doesn't mean that we can optimize and not go any
4513 // further back in the PreviousVersion generations. The EMCP
4514 // method for this generation could have already been made obsolete,
4515 // but there still may be an older EMCP method that has not
4516 // been made obsolete.
4517 }
4518
4519 if (++local_count >= obsolete_method_count) {
4520 // no more obsolete methods so bail out now
4521 break;
4522 }
4523 }
4524 }
4525 }
4526 }
4527
4528 // Save the scratch_class as the previous version if any of the methods are running.
4529 // The previous_versions are used to set breakpoints in EMCP methods and they are
4530 // also used to clean MethodData links to redefined methods that are no longer running.
4531 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4532 int emcp_method_count) {
4533 assert(Thread::current()->is_VM_thread(),
4534 "only VMThread can add previous versions");
4535
4536 ResourceMark rm;
4537 log_trace(redefine, class, iklass, add)
4538 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4539
4540 // Clean out old previous versions for this class
4541 purge_previous_version_list();
4542
4543 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4544 // a previous redefinition may be made obsolete by this redefinition.
4545 Array<Method*>* old_methods = scratch_class->methods();
4546 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4547
4548 // If the constant pool for this previous version of the class
4549 // is not marked as being on the stack, then none of the methods
4550 // in this previous version of the class are on the stack so
4551 // we don't need to add this as a previous version.
4552 ConstantPool* cp_ref = scratch_class->constants();
4553 if (!cp_ref->on_stack()) {
4554 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4555 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4556 return;
4557 }
4558
4559 // Add previous version if any methods are still running or if this is
4560 // a shared class which should never be removed.
4561 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4562 scratch_class->link_previous_versions(previous_versions());
4563 link_previous_versions(scratch_class);
4564 if (cp_ref->is_shared()) {
4565 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4566 } else {
4567 // We only set clean_previous_versions flag for processing during class
4568 // unloading for non-shared classes.
4569 _should_clean_previous_versions = true;
4570 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4571 }
4572 } // end add_previous_version()
4573
4574 #endif // INCLUDE_JVMTI
4575
4576 Method* InstanceKlass::method_with_idnum(int idnum) {
4577 Method* m = nullptr;
4578 if (idnum < methods()->length()) {
4579 m = methods()->at(idnum);
4580 }
4581 if (m == nullptr || m->method_idnum() != idnum) {
4582 for (int index = 0; index < methods()->length(); ++index) {
4583 m = methods()->at(index);
4584 if (m->method_idnum() == idnum) {
4585 return m;
4586 }
4587 }
4588 // None found, return null for the caller to handle.
4589 return nullptr;
4590 }
4591 return m;
4592 }
4593
4594
4595 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4596 if (idnum >= methods()->length()) {
4597 return nullptr;
4598 }
4599 Method* m = methods()->at(idnum);
4600 if (m != nullptr && m->orig_method_idnum() == idnum) {
4601 return m;
4602 }
4603 // Obsolete method idnum does not match the original idnum
4604 for (int index = 0; index < methods()->length(); ++index) {
4605 m = methods()->at(index);
4606 if (m->orig_method_idnum() == idnum) {
4607 return m;
4608 }
4609 }
4610 // None found, return null for the caller to handle.
4611 return nullptr;
4612 }
4613
4614
4615 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4616 InstanceKlass* holder = get_klass_version(version);
4617 if (holder == nullptr) {
4618 return nullptr; // The version of klass is gone, no method is found
4619 }
4620 Method* method = holder->method_with_orig_idnum(idnum);
4621 return method;
4622 }
4623
4624 #if INCLUDE_JVMTI
4625 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4626 return _cached_class_file;
4627 }
4628
4629 jint InstanceKlass::get_cached_class_file_len() {
4630 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4631 }
4632
4633 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4634 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4635 }
4636 #endif
4637
4638 // Make a step iterating over the class hierarchy under the root class.
4639 // Skips subclasses if requested.
4640 void ClassHierarchyIterator::next() {
4641 assert(_current != nullptr, "required");
4642 if (_visit_subclasses && _current->subklass() != nullptr) {
4643 _current = _current->subklass();
4644 return; // visit next subclass
4645 }
4646 _visit_subclasses = true; // reset
4647 while (_current->next_sibling() == nullptr && _current != _root) {
4648 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4649 }
4650 if (_current == _root) {
4651 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4652 _current = nullptr;
4653 return;
4654 }
4655 _current = _current->next_sibling();
4656 return; // visit next sibling subclass
4657 }