1 /*
2 * Copyright (c) 1997, 2024, 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/archiveUtils.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/classListWriter.hpp"
29 #include "cds/heapShared.hpp"
30 #include "cds/metaspaceShared.hpp"
31 #include "classfile/classFileParser.hpp"
32 #include "classfile/classFileStream.hpp"
33 #include "classfile/classLoader.hpp"
34 #include "classfile/classLoaderData.inline.hpp"
35 #include "classfile/javaClasses.hpp"
36 #include "classfile/moduleEntry.hpp"
37 #include "classfile/systemDictionary.hpp"
38 #include "classfile/systemDictionaryShared.hpp"
39 #include "classfile/verifier.hpp"
40 #include "classfile/vmClasses.hpp"
41 #include "classfile/vmSymbols.hpp"
42 #include "code/codeCache.hpp"
43 #include "code/dependencyContext.hpp"
44 #include "compiler/compilationPolicy.hpp"
45 #include "compiler/compileBroker.hpp"
46 #include "gc/shared/collectedHeap.inline.hpp"
47 #include "interpreter/bytecodeStream.hpp"
48 #include "interpreter/oopMapCache.hpp"
49 #include "interpreter/rewriter.hpp"
50 #include "jvm.h"
51 #include "jvmtifiles/jvmti.h"
52 #include "logging/log.hpp"
53 #include "logging/logMessage.hpp"
54 #include "logging/logStream.hpp"
55 #include "memory/allocation.inline.hpp"
56 #include "memory/iterator.inline.hpp"
57 #include "memory/metadataFactory.hpp"
58 #include "memory/metaspaceClosure.hpp"
59 #include "memory/oopFactory.hpp"
60 #include "memory/resourceArea.hpp"
61 #include "memory/universe.hpp"
62 #include "oops/fieldStreams.inline.hpp"
63 #include "oops/constantPool.hpp"
64 #include "oops/instanceClassLoaderKlass.hpp"
65 #include "oops/instanceKlass.inline.hpp"
66 #include "oops/instanceMirrorKlass.hpp"
67 #include "oops/instanceOop.hpp"
68 #include "oops/instanceStackChunkKlass.hpp"
69 #include "oops/klass.inline.hpp"
70 #include "oops/method.hpp"
71 #include "oops/oop.inline.hpp"
72 #include "oops/recordComponent.hpp"
73 #include "oops/symbol.hpp"
74 #include "oops/inlineKlass.hpp"
75 #include "prims/jvmtiExport.hpp"
76 #include "prims/jvmtiRedefineClasses.hpp"
77 #include "prims/jvmtiThreadState.hpp"
78 #include "prims/methodComparator.hpp"
79 #include "runtime/arguments.hpp"
80 #include "runtime/deoptimization.hpp"
81 #include "runtime/atomic.hpp"
82 #include "runtime/fieldDescriptor.inline.hpp"
83 #include "runtime/handles.inline.hpp"
84 #include "runtime/javaCalls.hpp"
85 #include "runtime/javaThread.inline.hpp"
86 #include "runtime/mutexLocker.hpp"
87 #include "runtime/orderAccess.hpp"
88 #include "runtime/os.inline.hpp"
89 #include "runtime/reflectionUtils.hpp"
90 #include "runtime/threads.hpp"
91 #include "services/classLoadingService.hpp"
92 #include "services/finalizerService.hpp"
93 #include "services/threadService.hpp"
94 #include "utilities/dtrace.hpp"
95 #include "utilities/events.hpp"
96 #include "utilities/macros.hpp"
97 #include "utilities/stringUtils.hpp"
98 #include "utilities/pair.hpp"
99 #ifdef COMPILER1
100 #include "c1/c1_Compiler.hpp"
101 #endif
102 #if INCLUDE_JFR
103 #include "jfr/jfrEvents.hpp"
104 #endif
105
106 #ifdef DTRACE_ENABLED
107
108
109 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
110 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
111 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
112 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
113 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
114 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
115 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
116 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
117 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
118 { \
119 char* data = nullptr; \
120 int len = 0; \
121 Symbol* clss_name = name(); \
122 if (clss_name != nullptr) { \
123 data = (char*)clss_name->bytes(); \
124 len = clss_name->utf8_length(); \
125 } \
126 HOTSPOT_CLASS_INITIALIZATION_##type( \
127 data, len, (void*)class_loader(), thread_type); \
128 }
129
130 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
131 { \
132 char* data = nullptr; \
133 int len = 0; \
134 Symbol* clss_name = name(); \
135 if (clss_name != nullptr) { \
136 data = (char*)clss_name->bytes(); \
137 len = clss_name->utf8_length(); \
138 } \
139 HOTSPOT_CLASS_INITIALIZATION_##type( \
140 data, len, (void*)class_loader(), thread_type, wait); \
141 }
142
143 #else // ndef DTRACE_ENABLED
144
145 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
146 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
147
148 #endif // ndef DTRACE_ENABLED
149
150 bool InstanceKlass::_finalization_enabled = true;
151
152 static inline bool is_class_loader(const Symbol* class_name,
153 const ClassFileParser& parser) {
154 assert(class_name != nullptr, "invariant");
155
156 if (class_name == vmSymbols::java_lang_ClassLoader()) {
157 return true;
158 }
159
160 if (vmClasses::ClassLoader_klass_loaded()) {
161 const Klass* const super_klass = parser.super_klass();
162 if (super_klass != nullptr) {
163 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
164 return true;
165 }
166 }
167 }
168 return false;
169 }
170
171 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
172 return field(index).field_flags().is_null_free_inline_type();
173 }
174
175 bool InstanceKlass::is_class_in_preload_attribute(Symbol* name) const {
176 if (_preload_classes == nullptr) return false;
177 for (int i = 0; i < _preload_classes->length(); i++) {
178 Symbol* class_name = _constants->klass_at_noresolve(_preload_classes->at(i));
179 if (class_name == name) return true;
180 }
181 return false;
182 }
183
184 static inline bool is_stack_chunk_class(const Symbol* class_name,
185 const ClassLoaderData* loader_data) {
186 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
187 loader_data->is_the_null_class_loader_data());
188 }
189
190 // private: called to verify that k is a static member of this nest.
191 // We know that k is an instance class in the same package and hence the
192 // same classloader.
193 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
194 assert(!is_hidden(), "unexpected hidden class");
195 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
196 if (log_is_enabled(Trace, class, nestmates)) {
197 ResourceMark rm(current);
198 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
199 k->external_name(), this->external_name());
200 }
201 return false;
202 }
203
204 if (log_is_enabled(Trace, class, nestmates)) {
205 ResourceMark rm(current);
206 log_trace(class, nestmates)("Checking nest membership of %s in %s",
207 k->external_name(), this->external_name());
208 }
209
210 // Check for the named class in _nest_members.
211 // We don't resolve, or load, any classes.
212 for (int i = 0; i < _nest_members->length(); i++) {
213 int cp_index = _nest_members->at(i);
214 Symbol* name = _constants->klass_name_at(cp_index);
215 if (name == k->name()) {
216 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
217 return true;
218 }
219 }
220 log_trace(class, nestmates)("- class is NOT a nest member!");
221 return false;
222 }
223
224 // Called to verify that k is a permitted subclass of this class
225 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
226 Thread* current = Thread::current();
227 assert(k != nullptr, "sanity check");
228 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
229 "unexpected empty _permitted_subclasses array");
230
231 if (log_is_enabled(Trace, class, sealed)) {
232 ResourceMark rm(current);
233 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
234 k->external_name(), this->external_name());
235 }
236
237 // Check that the class and its super are in the same module.
238 if (k->module() != this->module()) {
239 ResourceMark rm(current);
240 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
241 k->external_name(), this->external_name());
242 return false;
243 }
244
245 if (!k->is_public() && !is_same_class_package(k)) {
246 ResourceMark rm(current);
247 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
248 k->external_name(), this->external_name());
249 return false;
250 }
251
252 for (int i = 0; i < _permitted_subclasses->length(); i++) {
253 int cp_index = _permitted_subclasses->at(i);
254 Symbol* name = _constants->klass_name_at(cp_index);
255 if (name == k->name()) {
256 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
257 return true;
258 }
259 }
260 log_trace(class, sealed)("- class is NOT a permitted subclass!");
261 return false;
262 }
263
264 // Return nest-host class, resolving, validating and saving it if needed.
265 // In cases where this is called from a thread that cannot do classloading
266 // (such as a native JIT thread) then we simply return null, which in turn
267 // causes the access check to return false. Such code will retry the access
268 // from a more suitable environment later. Otherwise the _nest_host is always
269 // set once this method returns.
270 // Any errors from nest-host resolution must be preserved so they can be queried
271 // from higher-level access checking code, and reported as part of access checking
272 // exceptions.
273 // VirtualMachineErrors are propagated with a null return.
274 // Under any conditions where the _nest_host can be set to non-null the resulting
275 // value of it and, if applicable, the nest host resolution/validation error,
276 // are idempotent.
277 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
278 InstanceKlass* nest_host_k = _nest_host;
279 if (nest_host_k != nullptr) {
280 return nest_host_k;
281 }
282
283 ResourceMark rm(THREAD);
284
285 // need to resolve and save our nest-host class.
286 if (_nest_host_index != 0) { // we have a real nest_host
287 // Before trying to resolve check if we're in a suitable context
288 bool can_resolve = THREAD->can_call_java();
289 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
290 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
291 this->external_name());
292 return nullptr; // sentinel to say "try again from a different context"
293 }
294
295 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
296 this->external_name(),
297 _constants->klass_name_at(_nest_host_index)->as_C_string());
298
299 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
300 if (HAS_PENDING_EXCEPTION) {
301 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
302 return nullptr; // propagate VMEs
303 }
304 stringStream ss;
305 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
306 ss.print("Nest host resolution of %s with host %s failed: ",
307 this->external_name(), target_host_class);
308 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
309 const char* msg = ss.as_string(true /* on C-heap */);
310 constantPoolHandle cph(THREAD, constants());
311 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
312 CLEAR_PENDING_EXCEPTION;
313
314 log_trace(class, nestmates)("%s", msg);
315 } else {
316 // A valid nest-host is an instance class in the current package that lists this
317 // class as a nest member. If any of these conditions are not met the class is
318 // its own nest-host.
319 const char* error = nullptr;
320
321 // JVMS 5.4.4 indicates package check comes first
322 if (is_same_class_package(k)) {
323 // Now check actual membership. We can't be a member if our "host" is
324 // not an instance class.
325 if (k->is_instance_klass()) {
326 nest_host_k = InstanceKlass::cast(k);
327 bool is_member = nest_host_k->has_nest_member(THREAD, this);
328 if (is_member) {
329 _nest_host = nest_host_k; // save resolved nest-host value
330
331 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
332 this->external_name(), k->external_name());
333 return nest_host_k;
334 } else {
335 error = "current type is not listed as a nest member";
336 }
337 } else {
338 error = "host is not an instance class";
339 }
340 } else {
341 error = "types are in different packages";
342 }
343
344 // something went wrong, so record what and log it
345 {
346 stringStream ss;
347 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
348 this->external_name(),
349 this->class_loader_data()->loader_name_and_id(),
350 k->external_name(),
351 k->class_loader_data()->loader_name_and_id(),
352 error);
353 const char* msg = ss.as_string(true /* on C-heap */);
354 constantPoolHandle cph(THREAD, constants());
355 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
356 log_trace(class, nestmates)("%s", msg);
357 }
358 }
359 } else {
360 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
361 this->external_name());
362 }
363
364 // Either not in an explicit nest, or else an error occurred, so
365 // the nest-host is set to `this`. Any thread that sees this assignment
366 // will also see any setting of nest_host_error(), if applicable.
367 return (_nest_host = this);
368 }
369
370 // Dynamic nest member support: set this class's nest host to the given class.
371 // This occurs as part of the class definition, as soon as the instanceKlass
372 // has been created and doesn't require further resolution. The code:
373 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
374 // results in:
375 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
376 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
377 // We also know the "host" is a valid nest-host in the same package so we can
378 // assert some of those facts.
379 void InstanceKlass::set_nest_host(InstanceKlass* host) {
380 assert(is_hidden(), "must be a hidden class");
381 assert(host != nullptr, "null nest host specified");
382 assert(_nest_host == nullptr, "current class has resolved nest-host");
383 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
384 nest_host_error());
385 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
386 (host->_nest_host == host), "proposed host is not a valid nest-host");
387 // Can't assert this as package is not set yet:
388 // assert(is_same_class_package(host), "proposed host is in wrong package");
389
390 if (log_is_enabled(Trace, class, nestmates)) {
391 ResourceMark rm;
392 const char* msg = "";
393 // a hidden class does not expect a statically defined nest-host
394 if (_nest_host_index > 0) {
395 msg = "(the NestHost attribute in the current class is ignored)";
396 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
397 msg = "(the NestMembers attribute in the current class is ignored)";
398 }
399 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
400 this->external_name(),
401 host->external_name(),
402 msg);
403 }
404 // set dynamic nest host
405 _nest_host = host;
406 // Record dependency to keep nest host from being unloaded before this class.
407 ClassLoaderData* this_key = class_loader_data();
408 assert(this_key != nullptr, "sanity");
409 this_key->record_dependency(host);
410 }
411
412 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
413 // or we are k's nest_host - all of which is covered by comparing the two
414 // resolved_nest_hosts.
415 // Any exceptions (i.e. VMEs) are propagated.
416 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
417
418 assert(this != k, "this should be handled by higher-level code");
419
420 // Per JVMS 5.4.4 we first resolve and validate the current class, then
421 // the target class k.
422
423 InstanceKlass* cur_host = nest_host(CHECK_false);
424 if (cur_host == nullptr) {
425 return false;
426 }
427
428 Klass* k_nest_host = k->nest_host(CHECK_false);
429 if (k_nest_host == nullptr) {
430 return false;
431 }
432
433 bool access = (cur_host == k_nest_host);
434
435 ResourceMark rm(THREAD);
436 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
437 this->external_name(),
438 access ? "" : "NOT ",
439 k->external_name());
440 return access;
441 }
442
443 const char* InstanceKlass::nest_host_error() {
444 if (_nest_host_index == 0) {
445 return nullptr;
446 } else {
447 constantPoolHandle cph(Thread::current(), constants());
448 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
449 }
450 }
451
452 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
453 const int size = InstanceKlass::size(parser.vtable_size(),
454 parser.itable_size(),
455 nonstatic_oop_map_size(parser.total_oop_map_count()),
456 parser.is_interface(),
457 parser.is_inline_type());
458
459 const Symbol* const class_name = parser.class_name();
460 assert(class_name != nullptr, "invariant");
461 ClassLoaderData* loader_data = parser.loader_data();
462 assert(loader_data != nullptr, "invariant");
463
464 InstanceKlass* ik;
465
466 // Allocation
467 if (parser.is_instance_ref_klass()) {
468 // java.lang.ref.Reference
469 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
470 } else if (class_name == vmSymbols::java_lang_Class()) {
471 // mirror - java.lang.Class
472 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
473 } else if (is_stack_chunk_class(class_name, loader_data)) {
474 // stack chunk
475 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
476 } else if (is_class_loader(class_name, parser)) {
477 // class loader - java.lang.ClassLoader
478 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
479 } else if (parser.is_inline_type()) {
480 // inline type
481 ik = new (loader_data, size, THREAD) InlineKlass(parser);
482 } else {
483 // normal
484 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
485 }
486
487 // Check for pending exception before adding to the loader data and incrementing
488 // class count. Can get OOM here.
489 if (HAS_PENDING_EXCEPTION) {
490 return nullptr;
491 }
492
493 #ifdef ASSERT
494 ik->bounds_check((address) ik->start_of_vtable(), false, size);
495 ik->bounds_check((address) ik->start_of_itable(), false, size);
496 ik->bounds_check((address) ik->end_of_itable(), true, size);
497 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
498 #endif //ASSERT
499 return ik;
500 }
501
502 #ifndef PRODUCT
503 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
504 const char* bad = nullptr;
505 address end = nullptr;
506 if (addr < (address)this) {
507 bad = "before";
508 } else if (addr == (address)this) {
509 if (edge_ok) return true;
510 bad = "just before";
511 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
512 if (edge_ok) return true;
513 bad = "just after";
514 } else if (addr > end) {
515 bad = "after";
516 } else {
517 return true;
518 }
519 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
520 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
521 Verbose = WizardMode = true; this->print(); //@@
522 return false;
523 }
524 #endif //PRODUCT
525
526 // copy method ordering from resource area to Metaspace
527 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
528 if (m != nullptr) {
529 // allocate a new array and copy contents (memcpy?)
530 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
531 for (int i = 0; i < m->length(); i++) {
532 _method_ordering->at_put(i, m->at(i));
533 }
534 } else {
535 _method_ordering = Universe::the_empty_int_array();
536 }
537 }
538
539 // create a new array of vtable_indices for default methods
540 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
541 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
542 assert(default_vtable_indices() == nullptr, "only create once");
543 set_default_vtable_indices(vtable_indices);
544 return vtable_indices;
545 }
546
547 static Monitor* create_init_monitor(const char* name) {
548 return new Monitor(Mutex::safepoint, name);
549 }
550
551 InstanceKlass::InstanceKlass() {
552 assert(CDSConfig::is_dumping_static_archive() || UseSharedSpaces, "only for CDS");
553 }
554
555 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
556 Klass(kind),
557 _nest_members(nullptr),
558 _nest_host(nullptr),
559 _permitted_subclasses(nullptr),
560 _record_components(nullptr),
561 _static_field_size(parser.static_field_size()),
562 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
563 _itable_len(parser.itable_size()),
564 _nest_host_index(0),
565 _init_state(allocated),
566 _reference_type(reference_type),
567 _init_monitor(create_init_monitor("InstanceKlassInitMonitor_lock")),
568 _init_thread(nullptr),
569 _inline_type_field_klasses(nullptr),
570 _preload_classes(nullptr),
571 _adr_inlineklass_fixed_block(nullptr)
572 {
573 set_vtable_length(parser.vtable_size());
574 set_access_flags(parser.access_flags());
575 if (parser.is_hidden()) set_is_hidden();
576 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
577 false));
578 if (parser.has_inline_fields()) {
579 set_has_inline_type_fields();
580 }
581
582 assert(nullptr == _methods, "underlying memory not zeroed?");
583 assert(is_instance_klass(), "is layout incorrect?");
584 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
585 }
586
587 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
588 Array<Method*>* methods) {
589 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
590 !methods->is_shared()) {
591 for (int i = 0; i < methods->length(); i++) {
592 Method* method = methods->at(i);
593 if (method == nullptr) continue; // maybe null if error processing
594 // Only want to delete methods that are not executing for RedefineClasses.
595 // The previous version will point to them so they're not totally dangling
596 assert (!method->on_stack(), "shouldn't be called with methods on stack");
597 MetadataFactory::free_metadata(loader_data, method);
598 }
599 MetadataFactory::free_array<Method*>(loader_data, methods);
600 }
601 }
602
603 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
604 const Klass* super_klass,
605 Array<InstanceKlass*>* local_interfaces,
606 Array<InstanceKlass*>* transitive_interfaces) {
607 // Only deallocate transitive interfaces if not empty, same as super class
608 // or same as local interfaces. See code in parseClassFile.
609 Array<InstanceKlass*>* ti = transitive_interfaces;
610 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
611 // check that the interfaces don't come from super class
612 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
613 InstanceKlass::cast(super_klass)->transitive_interfaces();
614 if (ti != sti && ti != nullptr && !ti->is_shared()) {
615 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
616 }
617 }
618
619 // local interfaces can be empty
620 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
621 local_interfaces != nullptr && !local_interfaces->is_shared()) {
622 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
623 }
624 }
625
626 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
627 Array<RecordComponent*>* record_components) {
628 if (record_components != nullptr && !record_components->is_shared()) {
629 for (int i = 0; i < record_components->length(); i++) {
630 RecordComponent* record_component = record_components->at(i);
631 MetadataFactory::free_metadata(loader_data, record_component);
632 }
633 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
634 }
635 }
636
637 // This function deallocates the metadata and C heap pointers that the
638 // InstanceKlass points to.
639 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
640 // Orphan the mirror first, CMS thinks it's still live.
641 if (java_mirror() != nullptr) {
642 java_lang_Class::set_klass(java_mirror(), nullptr);
643 }
644
645 // Also remove mirror from handles
646 loader_data->remove_handle(_java_mirror);
647
648 // Need to take this class off the class loader data list.
649 loader_data->remove_class(this);
650
651 // The array_klass for this class is created later, after error handling.
652 // For class redefinition, we keep the original class so this scratch class
653 // doesn't have an array class. Either way, assert that there is nothing
654 // to deallocate.
655 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
656
657 // Release C heap allocated data that this points to, which includes
658 // reference counting symbol names.
659 // Can't release the constant pool or MethodData C heap data here because the constant
660 // pool can be deallocated separately from the InstanceKlass for default methods and
661 // redefine classes. MethodData can also be released separately.
662 release_C_heap_structures(/* release_sub_metadata */ false);
663
664 deallocate_methods(loader_data, methods());
665 set_methods(nullptr);
666
667 deallocate_record_components(loader_data, record_components());
668 set_record_components(nullptr);
669
670 if (method_ordering() != nullptr &&
671 method_ordering() != Universe::the_empty_int_array() &&
672 !method_ordering()->is_shared()) {
673 MetadataFactory::free_array<int>(loader_data, method_ordering());
674 }
675 set_method_ordering(nullptr);
676
677 // default methods can be empty
678 if (default_methods() != nullptr &&
679 default_methods() != Universe::the_empty_method_array() &&
680 !default_methods()->is_shared()) {
681 MetadataFactory::free_array<Method*>(loader_data, default_methods());
682 }
683 // Do NOT deallocate the default methods, they are owned by superinterfaces.
684 set_default_methods(nullptr);
685
686 // default methods vtable indices can be empty
687 if (default_vtable_indices() != nullptr &&
688 !default_vtable_indices()->is_shared()) {
689 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
690 }
691 set_default_vtable_indices(nullptr);
692
693
694 // This array is in Klass, but remove it with the InstanceKlass since
695 // this place would be the only caller and it can share memory with transitive
696 // interfaces.
697 if (secondary_supers() != nullptr &&
698 secondary_supers() != Universe::the_empty_klass_array() &&
699 // see comments in compute_secondary_supers about the following cast
700 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
701 !secondary_supers()->is_shared()) {
702 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
703 }
704 set_secondary_supers(nullptr);
705
706 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
707 set_transitive_interfaces(nullptr);
708 set_local_interfaces(nullptr);
709
710 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
711 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
712 }
713 set_fieldinfo_stream(nullptr);
714
715 if (fields_status() != nullptr && !fields_status()->is_shared()) {
716 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
717 }
718 set_fields_status(nullptr);
719
720 if (inline_type_field_klasses_array() != nullptr) {
721 MetadataFactory::free_array<InlineKlass*>(loader_data, inline_type_field_klasses_array());
722 }
723 set_inline_type_field_klasses_array(nullptr);
724
725 // If a method from a redefined class is using this constant pool, don't
726 // delete it, yet. The new class's previous version will point to this.
727 if (constants() != nullptr) {
728 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
729 if (!constants()->is_shared()) {
730 MetadataFactory::free_metadata(loader_data, constants());
731 }
732 // Delete any cached resolution errors for the constant pool
733 SystemDictionary::delete_resolution_error(constants());
734
735 set_constants(nullptr);
736 }
737
738 if (inner_classes() != nullptr &&
739 inner_classes() != Universe::the_empty_short_array() &&
740 !inner_classes()->is_shared()) {
741 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
742 }
743 set_inner_classes(nullptr);
744
745 if (nest_members() != nullptr &&
746 nest_members() != Universe::the_empty_short_array() &&
747 !nest_members()->is_shared()) {
748 MetadataFactory::free_array<jushort>(loader_data, nest_members());
749 }
750 set_nest_members(nullptr);
751
752 if (permitted_subclasses() != nullptr &&
753 permitted_subclasses() != Universe::the_empty_short_array() &&
754 !permitted_subclasses()->is_shared()) {
755 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
756 }
757 set_permitted_subclasses(nullptr);
758
759 if (preload_classes() != nullptr &&
760 preload_classes() != Universe::the_empty_short_array() &&
761 !preload_classes()->is_shared()) {
762 MetadataFactory::free_array<jushort>(loader_data, preload_classes());
763 }
764
765 // We should deallocate the Annotations instance if it's not in shared spaces.
766 if (annotations() != nullptr && !annotations()->is_shared()) {
767 MetadataFactory::free_metadata(loader_data, annotations());
768 }
769 set_annotations(nullptr);
770
771 SystemDictionaryShared::handle_class_unloading(this);
772
773 #if INCLUDE_CDS_JAVA_HEAP
774 if (CDSConfig::is_dumping_heap()) {
775 HeapShared::remove_scratch_objects(this);
776 }
777 #endif
778 }
779
780 bool InstanceKlass::is_record() const {
781 return _record_components != nullptr &&
782 is_final() &&
783 java_super() == vmClasses::Record_klass();
784 }
785
786 bool InstanceKlass::is_sealed() const {
787 return _permitted_subclasses != nullptr &&
788 _permitted_subclasses != Universe::the_empty_short_array();
789 }
790
791 bool InstanceKlass::should_be_initialized() const {
792 return !is_initialized();
793 }
794
795 klassItable InstanceKlass::itable() const {
796 return klassItable(const_cast<InstanceKlass*>(this));
797 }
798
799 // JVMTI spec thinks there are signers and protection domain in the
800 // instanceKlass. These accessors pretend these fields are there.
801 // The hprof specification also thinks these fields are in InstanceKlass.
802 oop InstanceKlass::protection_domain() const {
803 // return the protection_domain from the mirror
804 return java_lang_Class::protection_domain(java_mirror());
805 }
806
807 objArrayOop InstanceKlass::signers() const {
808 // return the signers from the mirror
809 return java_lang_Class::signers(java_mirror());
810 }
811
812 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
813 // process. The step comments refers to the procedure described in that section.
814 // Note: implementation moved to static method to expose the this pointer.
815 void InstanceKlass::initialize(TRAPS) {
816 if (this->should_be_initialized()) {
817 initialize_impl(CHECK);
818 // Note: at this point the class may be initialized
819 // OR it may be in the state of being initialized
820 // in case of recursive initialization!
821 } else {
822 assert(is_initialized(), "sanity check");
823 }
824 }
825
826
827 bool InstanceKlass::verify_code(TRAPS) {
828 // 1) Verify the bytecodes
829 return Verifier::verify(this, should_verify_class(), THREAD);
830 }
831
832 void InstanceKlass::link_class(TRAPS) {
833 assert(is_loaded(), "must be loaded");
834 if (!is_linked()) {
835 link_class_impl(CHECK);
836 }
837 }
838
839 void InstanceKlass::check_link_state_and_wait(JavaThread* current) {
840 MonitorLocker ml(current, _init_monitor);
841
842 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
843
844 // Another thread is linking this class, wait.
845 while (is_being_linked() && !is_init_thread(current)) {
846 if (debug_logging_enabled) {
847 ResourceMark rm(current);
848 log_debug(class, init)("Thread \"%s\" waiting for linking of %s by thread \"%s\"",
849 current->name(), external_name(), init_thread_name());
850 }
851 ml.wait();
852 }
853
854 // This thread is recursively linking this class, continue
855 if (is_being_linked() && is_init_thread(current)) {
856 if (debug_logging_enabled) {
857 ResourceMark rm(current);
858 log_debug(class, init)("Thread \"%s\" recursively linking %s",
859 current->name(), external_name());
860 }
861 return;
862 }
863
864 // If this class wasn't linked already, set state to being_linked
865 if (!is_linked()) {
866 if (debug_logging_enabled) {
867 ResourceMark rm(current);
868 log_debug(class, init)("Thread \"%s\" linking %s",
869 current->name(), external_name());
870 }
871 set_init_state(being_linked);
872 set_init_thread(current);
873 } else {
874 if (debug_logging_enabled) {
875 ResourceMark rm(current);
876 log_debug(class, init)("Thread \"%s\" found %s already linked",
877 current->name(), external_name());
878 }
879 }
880 }
881
882 // Called to verify that a class can link during initialization, without
883 // throwing a VerifyError.
884 bool InstanceKlass::link_class_or_fail(TRAPS) {
885 assert(is_loaded(), "must be loaded");
886 if (!is_linked()) {
887 link_class_impl(CHECK_false);
888 }
889 return is_linked();
890 }
891
892 bool InstanceKlass::link_class_impl(TRAPS) {
893 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
894 // This is for CDS static dump only -- we use the in_error_state to indicate that
895 // the class has failed verification. Throwing the NoClassDefFoundError here is just
896 // a convenient way to stop repeat attempts to verify the same (bad) class.
897 //
898 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
899 // if we are executing Java code. This is not a problem for CDS dumping phase since
900 // it doesn't execute any Java code.
901 ResourceMark rm(THREAD);
902 Exceptions::fthrow(THREAD_AND_LOCATION,
903 vmSymbols::java_lang_NoClassDefFoundError(),
904 "Class %s, or one of its supertypes, failed class initialization",
905 external_name());
906 return false;
907 }
908 // return if already verified
909 if (is_linked()) {
910 return true;
911 }
912
913 // Timing
914 // timer handles recursion
915 JavaThread* jt = THREAD;
916
917 // link super class before linking this class
918 Klass* super_klass = super();
919 if (super_klass != nullptr) {
920 if (super_klass->is_interface()) { // check if super class is an interface
921 ResourceMark rm(THREAD);
922 Exceptions::fthrow(
923 THREAD_AND_LOCATION,
924 vmSymbols::java_lang_IncompatibleClassChangeError(),
925 "class %s has interface %s as super class",
926 external_name(),
927 super_klass->external_name()
928 );
929 return false;
930 }
931
932 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
933 ik_super->link_class_impl(CHECK_false);
934 }
935
936 // link all interfaces implemented by this class before linking this class
937 Array<InstanceKlass*>* interfaces = local_interfaces();
938 int num_interfaces = interfaces->length();
939 for (int index = 0; index < num_interfaces; index++) {
940 InstanceKlass* interk = interfaces->at(index);
941 interk->link_class_impl(CHECK_false);
942 }
943
944
945 // If a class declares a method that uses an inline class as an argument
946 // type or return inline type, this inline class must be loaded during the
947 // linking of this class because size and properties of the inline class
948 // must be known in order to be able to perform inline type optimizations.
949 // The implementation below is an approximation of this rule, the code
950 // iterates over all methods of the current class (including overridden
951 // methods), not only the methods declared by this class. This
952 // approximation makes the code simpler, and doesn't change the semantic
953 // because classes declaring methods overridden by the current class are
954 // linked (and have performed their own pre-loading) before the linking
955 // of the current class.
956
957
958 // Note:
959 // Inline class types are loaded during
960 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
961 // Inline class types used as element types for array creation
962 // are not pre-loaded. Their loading is triggered by either anewarray
963 // or multianewarray bytecodes.
964
965 // Could it be possible to do the following processing only if the
966 // class uses inline types?
967 if (EnableValhalla) {
968 ResourceMark rm(THREAD);
969 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
970 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) {
971 Symbol* sig = fs.signature();
972 TempNewSymbol s = Signature::strip_envelope(sig);
973 if (s != name()) {
974 log_info(class, preload)("Preloading class %s during linking of class %s. Cause: a null-free static field is declared with this type", s->as_C_string(), name()->as_C_string());
975 Klass* klass = SystemDictionary::resolve_or_fail(s,
976 Handle(THREAD, class_loader()), Handle(THREAD, protection_domain()), true,
977 CHECK_false);
978 if (HAS_PENDING_EXCEPTION) {
979 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s",
980 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string());
981 return false; // Exception is still pending
982 }
983 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded",
984 s->as_C_string(), name()->as_C_string());
985 assert(klass != nullptr, "Sanity check");
986 if (!klass->is_inline_klass()) {
987 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
988 err_msg("class %s expects class %s to be a value class but it is an identity class",
989 name()->as_C_string(), klass->external_name()), false);
990 }
991 if (klass->is_abstract()) {
992 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
993 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class",
994 name()->as_C_string(),
995 InstanceKlass::cast(klass)->external_name()), false);
996 }
997 InstanceKlass* ik = InstanceKlass::cast(klass);
998 if (!ik->is_implicitly_constructible()) {
999 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
1000 err_msg("class %s is not implicitly constructible and it is used in a null restricted static field (not supported)",
1001 klass->external_name()), false);
1002 }
1003 // the inline_type_field_klass_array is not updated because of CDS (see verifications in SystemDictionary::load_shared_class())
1004 }
1005 }
1006 }
1007 // Aggressively preloading all classes from the Preload attribute
1008 if (preload_classes() != nullptr) {
1009 HandleMark hm(THREAD);
1010 for (int i = 0; i < preload_classes()->length(); i++) {
1011 if (constants()->tag_at(preload_classes()->at(i)).is_klass()) continue;
1012 Symbol* class_name = constants()->klass_at_noresolve(preload_classes()->at(i));
1013 if (class_name == name()) continue;
1014 log_info(class, preload)("Preloading class %s during linking of class %s because of the class is listed in the Preload attribute", class_name->as_C_string(), name()->as_C_string());
1015 oop loader = class_loader();
1016 oop protection_domain = this->protection_domain();
1017 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1018 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD);
1019 if (HAS_PENDING_EXCEPTION) {
1020 CLEAR_PENDING_EXCEPTION;
1021 }
1022 if (klass != nullptr) {
1023 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: Preload attribute) succeeded", class_name->as_C_string(), name()->as_C_string());
1024 if (!klass->is_inline_klass()) {
1025 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning
1026 log_warning(class, preload)("Preloading class %s during linking of class %s (cause: Preload attribute) but loaded class is not a value class", class_name->as_C_string(), name()->as_C_string());
1027 }
1028 } else {
1029 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: Preload attribute) failed", class_name->as_C_string(), name()->as_C_string());
1030 }
1031 }
1032 }
1033 }
1034
1035 // in case the class is linked in the process of linking its superclasses
1036 if (is_linked()) {
1037 return true;
1038 }
1039
1040 // trace only the link time for this klass that includes
1041 // the verification time
1042 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1043 ClassLoader::perf_class_link_selftime(),
1044 ClassLoader::perf_classes_linked(),
1045 jt->get_thread_stat()->perf_recursion_counts_addr(),
1046 jt->get_thread_stat()->perf_timers_addr(),
1047 PerfClassTraceTime::CLASS_LINK);
1048
1049 // verification & rewriting
1050 {
1051 LockLinkState init_lock(this, jt);
1052
1053 // rewritten will have been set if loader constraint error found
1054 // on an earlier link attempt
1055 // don't verify or rewrite if already rewritten
1056 //
1057
1058 if (!is_linked()) {
1059 if (!is_rewritten()) {
1060 if (is_shared()) {
1061 assert(!verified_at_dump_time(), "must be");
1062 }
1063 {
1064 bool verify_ok = verify_code(THREAD);
1065 if (!verify_ok) {
1066 return false;
1067 }
1068 }
1069
1070 // Just in case a side-effect of verify linked this class already
1071 // (which can sometimes happen since the verifier loads classes
1072 // using custom class loaders, which are free to initialize things)
1073 if (is_linked()) {
1074 return true;
1075 }
1076
1077 // also sets rewritten
1078 rewrite_class(CHECK_false);
1079 } else if (is_shared()) {
1080 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1081 }
1082
1083 // relocate jsrs and link methods after they are all rewritten
1084 link_methods(CHECK_false);
1085
1086 // Initialize the vtable and interface table after
1087 // methods have been rewritten since rewrite may
1088 // fabricate new Method*s.
1089 // also does loader constraint checking
1090 //
1091 // initialize_vtable and initialize_itable need to be rerun
1092 // for a shared class if
1093 // 1) the class is loaded by custom class loader or
1094 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1095 // 3) the class was not verified during dump time
1096 bool need_init_table = true;
1097 if (is_shared() && verified_at_dump_time() &&
1098 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1099 need_init_table = false;
1100 }
1101 if (need_init_table) {
1102 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1103 itable().initialize_itable_and_check_constraints(CHECK_false);
1104 }
1105 #ifdef ASSERT
1106 vtable().verify(tty, true);
1107 // In case itable verification is ever added.
1108 // itable().verify(tty, true);
1109 #endif
1110 set_initialization_state_and_notify(linked, THREAD);
1111 if (JvmtiExport::should_post_class_prepare()) {
1112 JvmtiExport::post_class_prepare(THREAD, this);
1113 }
1114 }
1115 }
1116 return true;
1117 }
1118
1119 // Rewrite the byte codes of all of the methods of a class.
1120 // The rewriter must be called exactly once. Rewriting must happen after
1121 // verification but before the first method of the class is executed.
1122 void InstanceKlass::rewrite_class(TRAPS) {
1123 assert(is_loaded(), "must be loaded");
1124 if (is_rewritten()) {
1125 assert(is_shared(), "rewriting an unshared class?");
1126 return;
1127 }
1128 Rewriter::rewrite(this, CHECK);
1129 set_rewritten();
1130 }
1131
1132 // Now relocate and link method entry points after class is rewritten.
1133 // This is outside is_rewritten flag. In case of an exception, it can be
1134 // executed more than once.
1135 void InstanceKlass::link_methods(TRAPS) {
1136 int len = methods()->length();
1137 for (int i = len-1; i >= 0; i--) {
1138 methodHandle m(THREAD, methods()->at(i));
1139
1140 // Set up method entry points for compiler and interpreter .
1141 m->link_method(m, CHECK);
1142 }
1143 }
1144
1145 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1146 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1147 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1148 for (int i = 0; i < local_interfaces()->length(); ++i) {
1149 InstanceKlass* ik = local_interfaces()->at(i);
1150
1151 // Initialization is depth first search ie. we start with top of the inheritance tree
1152 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1153 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1154 if (ik->has_nonstatic_concrete_methods()) {
1155 ik->initialize_super_interfaces(CHECK);
1156 }
1157
1158 // Only initialize() interfaces that "declare" concrete methods.
1159 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1160 ik->initialize(CHECK);
1161 }
1162 }
1163 }
1164
1165 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1166 static InitializationErrorTable* _initialization_error_table;
1167
1168 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1169 // Create the same exception with a message indicating the thread name,
1170 // and the StackTraceElements.
1171 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1172 ResourceMark rm(current);
1173 if (init_error.is_null()) {
1174 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1175
1176 // We failed to create the new exception, most likely due to either out-of-memory or
1177 // a stackoverflow error. If the original exception was either of those then we save
1178 // the shared, pre-allocated, stackless, instance of that exception.
1179 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1180 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1181 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1182 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1183 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1184 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1185 } else {
1186 return;
1187 }
1188 }
1189
1190 MutexLocker ml(current, ClassInitError_lock);
1191 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1192 bool created;
1193 if (_initialization_error_table == nullptr) {
1194 _initialization_error_table = new (mtClass) InitializationErrorTable();
1195 }
1196 _initialization_error_table->put_if_absent(this, elem, &created);
1197 assert(created, "Initialization is single threaded");
1198 log_trace(class, init)("Initialization error added for class %s", external_name());
1199 }
1200
1201 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1202 MutexLocker ml(current, ClassInitError_lock);
1203 if (_initialization_error_table == nullptr) {
1204 return nullptr;
1205 }
1206 OopHandle* h = _initialization_error_table->get(this);
1207 return (h != nullptr) ? h->resolve() : nullptr;
1208 }
1209
1210 // Need to remove entries for unloaded classes.
1211 void InstanceKlass::clean_initialization_error_table() {
1212 struct InitErrorTableCleaner {
1213 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1214 if (!ik->is_loader_alive()) {
1215 h.release(Universe::vm_global());
1216 return true;
1217 } else {
1218 return false;
1219 }
1220 }
1221 };
1222
1223 assert_locked_or_safepoint(ClassInitError_lock);
1224 InitErrorTableCleaner cleaner;
1225 if (_initialization_error_table != nullptr) {
1226 _initialization_error_table->unlink(&cleaner);
1227 }
1228 }
1229
1230 void InstanceKlass::initialize_impl(TRAPS) {
1231 HandleMark hm(THREAD);
1232
1233 // Make sure klass is linked (verified) before initialization
1234 // A class could already be verified, since it has been reflected upon.
1235 link_class(CHECK);
1236
1237 DTRACE_CLASSINIT_PROBE(required, -1);
1238
1239 bool wait = false;
1240 bool throw_error = false;
1241
1242 JavaThread* jt = THREAD;
1243
1244 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1245
1246 // refer to the JVM book page 47 for description of steps
1247 // Step 1
1248 {
1249 MonitorLocker ml(jt, _init_monitor);
1250
1251 // Step 2
1252 while (is_being_initialized() && !is_init_thread(jt)) {
1253 if (debug_logging_enabled) {
1254 ResourceMark rm(jt);
1255 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1256 jt->name(), external_name(), init_thread_name());
1257 }
1258
1259 wait = true;
1260 jt->set_class_to_be_initialized(this);
1261 ml.wait();
1262 jt->set_class_to_be_initialized(nullptr);
1263 }
1264
1265 // Step 3
1266 if (is_being_initialized() && is_init_thread(jt)) {
1267 if (debug_logging_enabled) {
1268 ResourceMark rm(jt);
1269 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1270 jt->name(), external_name());
1271 }
1272 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1273 return;
1274 }
1275
1276 // Step 4
1277 if (is_initialized()) {
1278 if (debug_logging_enabled) {
1279 ResourceMark rm(jt);
1280 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1281 jt->name(), external_name());
1282 }
1283 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1284 return;
1285 }
1286
1287 // Step 5
1288 if (is_in_error_state()) {
1289 if (debug_logging_enabled) {
1290 ResourceMark rm(jt);
1291 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1292 jt->name(), external_name());
1293 }
1294 throw_error = true;
1295 } else {
1296
1297 // Step 6
1298 set_init_state(being_initialized);
1299 set_init_thread(jt);
1300 if (debug_logging_enabled) {
1301 ResourceMark rm(jt);
1302 log_debug(class, init)("Thread \"%s\" is initializing %s",
1303 jt->name(), external_name());
1304 }
1305 }
1306 }
1307
1308 // Throw error outside lock
1309 if (throw_error) {
1310 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1311 ResourceMark rm(THREAD);
1312 Handle cause(THREAD, get_initialization_error(THREAD));
1313
1314 stringStream ss;
1315 ss.print("Could not initialize class %s", external_name());
1316 if (cause.is_null()) {
1317 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1318 } else {
1319 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1320 ss.as_string(), cause);
1321 }
1322 }
1323
1324 // Pre-allocating an instance of the default value
1325 if (is_inline_klass()) {
1326 InlineKlass* vk = InlineKlass::cast(this);
1327 oop val = vk->allocate_instance(THREAD);
1328 if (HAS_PENDING_EXCEPTION) {
1329 Handle e(THREAD, PENDING_EXCEPTION);
1330 CLEAR_PENDING_EXCEPTION;
1331 {
1332 EXCEPTION_MARK;
1333 add_initialization_error(THREAD, e);
1334 // Locks object, set state, and notify all waiting threads
1335 set_initialization_state_and_notify(initialization_error, THREAD);
1336 CLEAR_PENDING_EXCEPTION;
1337 }
1338 THROW_OOP(e());
1339 }
1340 vk->set_default_value(val);
1341 }
1342
1343 // Step 7
1344 // Next, if C is a class rather than an interface, initialize it's super class and super
1345 // interfaces.
1346 if (!is_interface()) {
1347 Klass* super_klass = super();
1348 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1349 super_klass->initialize(THREAD);
1350 }
1351 // If C implements any interface that declares a non-static, concrete method,
1352 // the initialization of C triggers initialization of its super interfaces.
1353 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1354 // having a superinterface that declares, non-static, concrete methods
1355 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1356 initialize_super_interfaces(THREAD);
1357 }
1358
1359 // If any exceptions, complete abruptly, throwing the same exception as above.
1360 if (HAS_PENDING_EXCEPTION) {
1361 Handle e(THREAD, PENDING_EXCEPTION);
1362 CLEAR_PENDING_EXCEPTION;
1363 {
1364 EXCEPTION_MARK;
1365 add_initialization_error(THREAD, e);
1366 // Locks object, set state, and notify all waiting threads
1367 set_initialization_state_and_notify(initialization_error, THREAD);
1368 CLEAR_PENDING_EXCEPTION;
1369 }
1370 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1371 THROW_OOP(e());
1372 }
1373 }
1374
1375 // Step 8
1376 // Initialize classes of inline fields
1377 if (EnableValhalla) {
1378 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1379 if (fs.is_null_free_inline_type()) {
1380 Klass* klass = get_inline_type_field_klass_or_null(fs.index());
1381 if (fs.access_flags().is_static() && klass == nullptr) {
1382 klass = SystemDictionary::resolve_or_fail(field_signature(fs.index())->fundamental_name(THREAD),
1383 Handle(THREAD, class_loader()),
1384 Handle(THREAD, protection_domain()),
1385 true, THREAD);
1386 assert(klass->is_inline_klass(), "Must be");
1387 set_inline_type_field_klass(fs.index(), InlineKlass::cast(klass));
1388 }
1389
1390 if (!HAS_PENDING_EXCEPTION) {
1391 assert(klass != nullptr, "Must be");
1392 InstanceKlass::cast(klass)->initialize(THREAD);
1393 if (fs.access_flags().is_static()) {
1394 if (java_mirror()->obj_field(fs.offset()) == nullptr) {
1395 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value());
1396 }
1397 }
1398 }
1399
1400 if (HAS_PENDING_EXCEPTION) {
1401 Handle e(THREAD, PENDING_EXCEPTION);
1402 CLEAR_PENDING_EXCEPTION;
1403 {
1404 EXCEPTION_MARK;
1405 add_initialization_error(THREAD, e);
1406 // Locks object, set state, and notify all waiting threads
1407 set_initialization_state_and_notify(initialization_error, THREAD);
1408 CLEAR_PENDING_EXCEPTION;
1409 }
1410 THROW_OOP(e());
1411 }
1412 }
1413 }
1414 }
1415
1416
1417 // Step 9
1418 {
1419 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1420 if (class_initializer() != nullptr) {
1421 // Timer includes any side effects of class initialization (resolution,
1422 // etc), but not recursive entry into call_class_initializer().
1423 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1424 ClassLoader::perf_class_init_selftime(),
1425 ClassLoader::perf_classes_inited(),
1426 jt->get_thread_stat()->perf_recursion_counts_addr(),
1427 jt->get_thread_stat()->perf_timers_addr(),
1428 PerfClassTraceTime::CLASS_CLINIT);
1429 call_class_initializer(THREAD);
1430 } else {
1431 // The elapsed time is so small it's not worth counting.
1432 if (UsePerfData) {
1433 ClassLoader::perf_classes_inited()->inc();
1434 }
1435 call_class_initializer(THREAD);
1436 }
1437 }
1438
1439 // Step 10
1440 if (!HAS_PENDING_EXCEPTION) {
1441 set_initialization_state_and_notify(fully_initialized, THREAD);
1442 debug_only(vtable().verify(tty, true);)
1443 }
1444 else {
1445 // Step 11 and 12
1446 Handle e(THREAD, PENDING_EXCEPTION);
1447 CLEAR_PENDING_EXCEPTION;
1448 // JVMTI has already reported the pending exception
1449 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1450 JvmtiExport::clear_detected_exception(jt);
1451 {
1452 EXCEPTION_MARK;
1453 add_initialization_error(THREAD, e);
1454 set_initialization_state_and_notify(initialization_error, THREAD);
1455 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1456 // JVMTI has already reported the pending exception
1457 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1458 JvmtiExport::clear_detected_exception(jt);
1459 }
1460 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1461 if (e->is_a(vmClasses::Error_klass())) {
1462 THROW_OOP(e());
1463 } else {
1464 JavaCallArguments args(e);
1465 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1466 vmSymbols::throwable_void_signature(),
1467 &args);
1468 }
1469 }
1470 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1471 }
1472
1473
1474 void InstanceKlass::set_initialization_state_and_notify(ClassState state, JavaThread* current) {
1475 MonitorLocker ml(current, _init_monitor);
1476
1477 if (state == linked && UseVtableBasedCHA && Universe::is_fully_initialized()) {
1478 DeoptimizationScope deopt_scope;
1479 {
1480 // Now mark all code that assumes the class is not linked.
1481 // Set state under the Compile_lock also.
1482 MutexLocker ml(current, Compile_lock);
1483
1484 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1485 set_init_state(state);
1486
1487 CodeCache::mark_dependents_on(&deopt_scope, this);
1488 }
1489 // Perform the deopt handshake outside Compile_lock.
1490 deopt_scope.deoptimize_marked();
1491 } else {
1492 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1493 set_init_state(state);
1494 }
1495 ml.notify_all();
1496 }
1497
1498 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1499 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1500 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1501 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1502
1503 // In case we are not using CHA based vtables we need to make sure the loaded
1504 // deopt is completed before anyone links this class.
1505 // Linking is done with _init_monitor held, by loading and deopting with it
1506 // held we make sure the deopt is completed before linking.
1507 if (!UseVtableBasedCHA) {
1508 init_monitor()->lock();
1509 }
1510
1511 DeoptimizationScope deopt_scope;
1512 {
1513 MutexLocker ml(current, Compile_lock);
1514
1515 set_init_state(InstanceKlass::loaded);
1516 // make sure init_state store is already done.
1517 // The compiler reads the hierarchy outside of the Compile_lock.
1518 // Access ordering is used to add to hierarchy.
1519
1520 // Link into hierarchy.
1521 append_to_sibling_list(); // add to superklass/sibling list
1522 process_interfaces(); // handle all "implements" declarations
1523
1524 // Now mark all code that depended on old class hierarchy.
1525 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1526 if (Universe::is_fully_initialized()) {
1527 CodeCache::mark_dependents_on(&deopt_scope, this);
1528 }
1529 }
1530 // Perform the deopt handshake outside Compile_lock.
1531 deopt_scope.deoptimize_marked();
1532
1533 if (!UseVtableBasedCHA) {
1534 init_monitor()->unlock();
1535 }
1536 }
1537
1538 InstanceKlass* InstanceKlass::implementor() const {
1539 InstanceKlass* volatile* ik = adr_implementor();
1540 if (ik == nullptr) {
1541 return nullptr;
1542 } else {
1543 // This load races with inserts, and therefore needs acquire.
1544 InstanceKlass* ikls = Atomic::load_acquire(ik);
1545 if (ikls != nullptr && !ikls->is_loader_alive()) {
1546 return nullptr; // don't return unloaded class
1547 } else {
1548 return ikls;
1549 }
1550 }
1551 }
1552
1553
1554 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1555 assert_locked_or_safepoint(Compile_lock);
1556 assert(is_interface(), "not interface");
1557 InstanceKlass* volatile* addr = adr_implementor();
1558 assert(addr != nullptr, "null addr");
1559 if (addr != nullptr) {
1560 Atomic::release_store(addr, ik);
1561 }
1562 }
1563
1564 int InstanceKlass::nof_implementors() const {
1565 InstanceKlass* ik = implementor();
1566 if (ik == nullptr) {
1567 return 0;
1568 } else if (ik != this) {
1569 return 1;
1570 } else {
1571 return 2;
1572 }
1573 }
1574
1575 // The embedded _implementor field can only record one implementor.
1576 // When there are more than one implementors, the _implementor field
1577 // is set to the interface Klass* itself. Following are the possible
1578 // values for the _implementor field:
1579 // null - no implementor
1580 // implementor Klass* - one implementor
1581 // self - more than one implementor
1582 //
1583 // The _implementor field only exists for interfaces.
1584 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1585 if (Universe::is_fully_initialized()) {
1586 assert_lock_strong(Compile_lock);
1587 }
1588 assert(is_interface(), "not interface");
1589 // Filter out my subinterfaces.
1590 // (Note: Interfaces are never on the subklass list.)
1591 if (ik->is_interface()) return;
1592
1593 // Filter out subclasses whose supers already implement me.
1594 // (Note: CHA must walk subclasses of direct implementors
1595 // in order to locate indirect implementors.)
1596 InstanceKlass* super_ik = ik->java_super();
1597 if (super_ik != nullptr && super_ik->implements_interface(this))
1598 // We only need to check one immediate superclass, since the
1599 // implements_interface query looks at transitive_interfaces.
1600 // Any supers of the super have the same (or fewer) transitive_interfaces.
1601 return;
1602
1603 InstanceKlass* iklass = implementor();
1604 if (iklass == nullptr) {
1605 set_implementor(ik);
1606 } else if (iklass != this && iklass != ik) {
1607 // There is already an implementor. Use itself as an indicator of
1608 // more than one implementors.
1609 set_implementor(this);
1610 }
1611
1612 // The implementor also implements the transitive_interfaces
1613 for (int index = 0; index < local_interfaces()->length(); index++) {
1614 local_interfaces()->at(index)->add_implementor(ik);
1615 }
1616 }
1617
1618 void InstanceKlass::init_implementor() {
1619 if (is_interface()) {
1620 set_implementor(nullptr);
1621 }
1622 }
1623
1624
1625 void InstanceKlass::process_interfaces() {
1626 // link this class into the implementors list of every interface it implements
1627 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1628 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1629 InstanceKlass* interf = local_interfaces()->at(i);
1630 assert(interf->is_interface(), "expected interface");
1631 interf->add_implementor(this);
1632 }
1633 }
1634
1635 bool InstanceKlass::can_be_primary_super_slow() const {
1636 if (is_interface())
1637 return false;
1638 else
1639 return Klass::can_be_primary_super_slow();
1640 }
1641
1642 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1643 Array<InstanceKlass*>* transitive_interfaces) {
1644 // The secondaries are the implemented interfaces.
1645 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1646 int num_secondaries = num_extra_slots + interfaces->length();
1647 if (num_secondaries == 0) {
1648 // Must share this for correct bootstrapping!
1649 set_secondary_supers(Universe::the_empty_klass_array());
1650 return nullptr;
1651 } else if (num_extra_slots == 0) {
1652 // The secondary super list is exactly the same as the transitive interfaces, so
1653 // let's use it instead of making a copy.
1654 // Redefine classes has to be careful not to delete this!
1655 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1656 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1657 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1658 return nullptr;
1659 } else {
1660 // Copy transitive interfaces to a temporary growable array to be constructed
1661 // into the secondary super list with extra slots.
1662 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1663 for (int i = 0; i < interfaces->length(); i++) {
1664 secondaries->push(interfaces->at(i));
1665 }
1666 return secondaries;
1667 }
1668 }
1669
1670 bool InstanceKlass::implements_interface(Klass* k) const {
1671 if (this == k) return true;
1672 assert(k->is_interface(), "should be an interface class");
1673 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1674 if (transitive_interfaces()->at(i) == k) {
1675 return true;
1676 }
1677 }
1678 return false;
1679 }
1680
1681 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1682 // Verify direct super interface
1683 if (this == k) return true;
1684 assert(k->is_interface(), "should be an interface class");
1685 for (int i = 0; i < local_interfaces()->length(); i++) {
1686 if (local_interfaces()->at(i) == k) {
1687 return true;
1688 }
1689 }
1690 return false;
1691 }
1692
1693 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1694 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1695 size_t size = objArrayOopDesc::object_size(length);
1696 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1697 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1698 /* do_zero */ true, CHECK_NULL);
1699 return o;
1700 }
1701
1702 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1703 if (TraceFinalizerRegistration) {
1704 tty->print("Registered ");
1705 i->print_value_on(tty);
1706 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1707 }
1708 instanceHandle h_i(THREAD, i);
1709 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1710 JavaValue result(T_VOID);
1711 JavaCallArguments args(h_i);
1712 methodHandle mh(THREAD, Universe::finalizer_register_method());
1713 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1714 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1715 return h_i();
1716 }
1717
1718 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1719 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1720 size_t size = size_helper(); // Query before forming handle.
1721
1722 instanceOop i;
1723
1724 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1725 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1726 i = register_finalizer(i, CHECK_NULL);
1727 }
1728 return i;
1729 }
1730
1731 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1732 Klass* k = java_lang_Class::as_Klass(java_class);
1733 if (k == nullptr) {
1734 ResourceMark rm(THREAD);
1735 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1736 }
1737 InstanceKlass* ik = cast(k);
1738 ik->check_valid_for_instantiation(false, CHECK_NULL);
1739 ik->initialize(CHECK_NULL);
1740 return ik->allocate_instance(THREAD);
1741 }
1742
1743 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1744 return instanceHandle(THREAD, allocate_instance(THREAD));
1745 }
1746
1747 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1748 if (is_interface() || is_abstract()) {
1749 ResourceMark rm(THREAD);
1750 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1751 : vmSymbols::java_lang_InstantiationException(), external_name());
1752 }
1753 if (this == vmClasses::Class_klass()) {
1754 ResourceMark rm(THREAD);
1755 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1756 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1757 }
1758 }
1759
1760 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1761 // Need load-acquire for lock-free read
1762 if (array_klasses_acquire() == nullptr) {
1763 ResourceMark rm(THREAD);
1764 JavaThread *jt = THREAD;
1765 {
1766 // Atomic creation of array_klasses
1767 MutexLocker ma(THREAD, MultiArray_lock);
1768
1769 // Check if update has already taken place
1770 if (array_klasses() == nullptr) {
1771 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this,
1772 false, CHECK_NULL);
1773 // use 'release' to pair with lock-free load
1774 release_set_array_klasses(k);
1775 }
1776 }
1777 }
1778 // array_klasses() will always be set at this point
1779 ArrayKlass* ak = array_klasses();
1780 return ak->array_klass(n, THREAD);
1781 }
1782
1783 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1784 // Need load-acquire for lock-free read
1785 ArrayKlass* ak = array_klasses_acquire();
1786 if (ak == nullptr) {
1787 return nullptr;
1788 } else {
1789 return ak->array_klass_or_null(n);
1790 }
1791 }
1792
1793 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1794 return array_klass(1, THREAD);
1795 }
1796
1797 ArrayKlass* InstanceKlass::array_klass_or_null() {
1798 return array_klass_or_null(1);
1799 }
1800
1801 static int call_class_initializer_counter = 0; // for debugging
1802
1803 Method* InstanceKlass::class_initializer() const {
1804 Method* clinit = find_method(
1805 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1806 if (clinit != nullptr && clinit->is_class_initializer()) {
1807 return clinit;
1808 }
1809 return nullptr;
1810 }
1811
1812 void InstanceKlass::call_class_initializer(TRAPS) {
1813 if (ReplayCompiles &&
1814 (ReplaySuppressInitializers == 1 ||
1815 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1816 // Hide the existence of the initializer for the purpose of replaying the compile
1817 return;
1818 }
1819
1820 #if INCLUDE_CDS
1821 // This is needed to ensure the consistency of the archived heap objects.
1822 if (has_archived_enum_objs()) {
1823 assert(is_shared(), "must be");
1824 bool initialized = HeapShared::initialize_enum_klass(this, CHECK);
1825 if (initialized) {
1826 return;
1827 }
1828 }
1829 #endif
1830
1831 methodHandle h_method(THREAD, class_initializer());
1832 assert(!is_initialized(), "we cannot initialize twice");
1833 LogTarget(Info, class, init) lt;
1834 if (lt.is_enabled()) {
1835 ResourceMark rm(THREAD);
1836 LogStream ls(lt);
1837 ls.print("%d Initializing ", call_class_initializer_counter++);
1838 name()->print_value_on(&ls);
1839 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1840 h_method() == nullptr ? "(no method)" : "", p2i(this),
1841 THREAD->name());
1842 }
1843 if (h_method() != nullptr) {
1844 JavaCallArguments args; // No arguments
1845 JavaValue result(T_VOID);
1846 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1847 }
1848 }
1849
1850
1851 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1852 InterpreterOopMap* entry_for) {
1853 // Lazily create the _oop_map_cache at first request
1854 // Lock-free access requires load_acquire.
1855 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1856 if (oop_map_cache == nullptr) {
1857 MutexLocker x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1858 // Check if _oop_map_cache was allocated while we were waiting for this lock
1859 if ((oop_map_cache = _oop_map_cache) == nullptr) {
1860 oop_map_cache = new OopMapCache();
1861 // Ensure _oop_map_cache is stable, since it is examined without a lock
1862 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1863 }
1864 }
1865 // _oop_map_cache is constant after init; lookup below does its own locking.
1866 oop_map_cache->lookup(method, bci, entry_for);
1867 }
1868
1869
1870 FieldInfo InstanceKlass::field(int index) const {
1871 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1872 if (fs.index() == index) {
1873 return fs.to_FieldInfo();
1874 }
1875 }
1876 fatal("Field not found");
1877 return FieldInfo();
1878 }
1879
1880 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1881 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1882 Symbol* f_name = fs.name();
1883 Symbol* f_sig = fs.signature();
1884 if (f_name == name && f_sig == sig) {
1885 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1886 return true;
1887 }
1888 }
1889 return false;
1890 }
1891
1892
1893 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1894 const int n = local_interfaces()->length();
1895 for (int i = 0; i < n; i++) {
1896 Klass* intf1 = local_interfaces()->at(i);
1897 assert(intf1->is_interface(), "just checking type");
1898 // search for field in current interface
1899 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1900 assert(fd->is_static(), "interface field must be static");
1901 return intf1;
1902 }
1903 // search for field in direct superinterfaces
1904 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1905 if (intf2 != nullptr) return intf2;
1906 }
1907 // otherwise field lookup fails
1908 return nullptr;
1909 }
1910
1911
1912 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1913 // search order according to newest JVM spec (5.4.3.2, p.167).
1914 // 1) search for field in current klass
1915 if (find_local_field(name, sig, fd)) {
1916 return const_cast<InstanceKlass*>(this);
1917 }
1918 // 2) search for field recursively in direct superinterfaces
1919 { Klass* intf = find_interface_field(name, sig, fd);
1920 if (intf != nullptr) return intf;
1921 }
1922 // 3) apply field lookup recursively if superclass exists
1923 { Klass* supr = super();
1924 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1925 }
1926 // 4) otherwise field lookup fails
1927 return nullptr;
1928 }
1929
1930
1931 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1932 // search order according to newest JVM spec (5.4.3.2, p.167).
1933 // 1) search for field in current klass
1934 if (find_local_field(name, sig, fd)) {
1935 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1936 }
1937 // 2) search for field recursively in direct superinterfaces
1938 if (is_static) {
1939 Klass* intf = find_interface_field(name, sig, fd);
1940 if (intf != nullptr) return intf;
1941 }
1942 // 3) apply field lookup recursively if superclass exists
1943 { Klass* supr = super();
1944 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1945 }
1946 // 4) otherwise field lookup fails
1947 return nullptr;
1948 }
1949
1950 bool InstanceKlass::contains_field_offset(int offset) {
1951 if (this->is_inline_klass()) {
1952 InlineKlass* vk = InlineKlass::cast(this);
1953 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->get_exact_size_in_bytes());
1954 } else {
1955 fieldDescriptor fd;
1956 return find_field_from_offset(offset, false, &fd);
1957 }
1958 }
1959
1960 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1961 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1962 if (fs.offset() == offset) {
1963 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1964 if (fd->is_static() == is_static) return true;
1965 }
1966 }
1967 return false;
1968 }
1969
1970
1971 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1972 Klass* klass = const_cast<InstanceKlass*>(this);
1973 while (klass != nullptr) {
1974 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1975 return true;
1976 }
1977 klass = klass->super();
1978 }
1979 return false;
1980 }
1981
1982
1983 void InstanceKlass::methods_do(void f(Method* method)) {
1984 // Methods aren't stable until they are loaded. This can be read outside
1985 // a lock through the ClassLoaderData for profiling
1986 // Redefined scratch classes are on the list and need to be cleaned
1987 if (!is_loaded() && !is_scratch_class()) {
1988 return;
1989 }
1990
1991 int len = methods()->length();
1992 for (int index = 0; index < len; index++) {
1993 Method* m = methods()->at(index);
1994 assert(m->is_method(), "must be method");
1995 f(m);
1996 }
1997 }
1998
1999
2000 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2001 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2002 if (fs.access_flags().is_static()) {
2003 fieldDescriptor& fd = fs.field_descriptor();
2004 cl->do_field(&fd);
2005 }
2006 }
2007 }
2008
2009
2010 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2011 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2012 if (fs.access_flags().is_static()) {
2013 fieldDescriptor& fd = fs.field_descriptor();
2014 f(&fd, mirror, CHECK);
2015 }
2016 }
2017 }
2018
2019 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2020 InstanceKlass* super = superklass();
2021 if (super != nullptr) {
2022 super->do_nonstatic_fields(cl);
2023 }
2024 fieldDescriptor fd;
2025 int length = java_fields_count();
2026 for (int i = 0; i < length; i += 1) {
2027 fd.reinitialize(this, i);
2028 if (!fd.is_static()) {
2029 cl->do_field(&fd);
2030 }
2031 }
2032 }
2033
2034 // first in Pair is offset, second is index.
2035 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2036 return a->first - b->first;
2037 }
2038
2039 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2040 InstanceKlass* super = superklass();
2041 if (super != nullptr) {
2042 super->print_nonstatic_fields(cl);
2043 }
2044 ResourceMark rm;
2045 fieldDescriptor fd;
2046 // In DebugInfo nonstatic fields are sorted by offset.
2047 GrowableArray<Pair<int,int> > fields_sorted;
2048 int i = 0;
2049 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2050 if (!fs.access_flags().is_static()) {
2051 fd = fs.field_descriptor();
2052 Pair<int,int> f(fs.offset(), fs.index());
2053 fields_sorted.push(f);
2054 i++;
2055 }
2056 }
2057 if (i > 0) {
2058 int length = i;
2059 assert(length == fields_sorted.length(), "duh");
2060 fields_sorted.sort(compare_fields_by_offset);
2061 for (int i = 0; i < length; i++) {
2062 fd.reinitialize(this, fields_sorted.at(i).second);
2063 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2064 cl->do_field(&fd);
2065 }
2066 }
2067 }
2068
2069 #ifdef ASSERT
2070 static int linear_search(const Array<Method*>* methods,
2071 const Symbol* name,
2072 const Symbol* signature) {
2073 const int len = methods->length();
2074 for (int index = 0; index < len; index++) {
2075 const Method* const m = methods->at(index);
2076 assert(m->is_method(), "must be method");
2077 if (m->signature() == signature && m->name() == name) {
2078 return index;
2079 }
2080 }
2081 return -1;
2082 }
2083 #endif
2084
2085 bool InstanceKlass::_disable_method_binary_search = false;
2086
2087 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2088 int len = methods->length();
2089 int l = 0;
2090 int h = len - 1;
2091 while (l <= h) {
2092 Method* m = methods->at(l);
2093 if (m->name() == name) {
2094 return l;
2095 }
2096 l++;
2097 }
2098 return -1;
2099 }
2100
2101 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2102 if (_disable_method_binary_search) {
2103 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2104 // At the final stage of dynamic dumping, the methods array may not be sorted
2105 // by ascending addresses of their names, so we can't use binary search anymore.
2106 // However, methods with the same name are still laid out consecutively inside the
2107 // methods array, so let's look for the first one that matches.
2108 return linear_search(methods, name);
2109 }
2110
2111 int len = methods->length();
2112 int l = 0;
2113 int h = len - 1;
2114
2115 // methods are sorted by ascending addresses of their names, so do binary search
2116 while (l <= h) {
2117 int mid = (l + h) >> 1;
2118 Method* m = methods->at(mid);
2119 assert(m->is_method(), "must be method");
2120 int res = m->name()->fast_compare(name);
2121 if (res == 0) {
2122 return mid;
2123 } else if (res < 0) {
2124 l = mid + 1;
2125 } else {
2126 h = mid - 1;
2127 }
2128 }
2129 return -1;
2130 }
2131
2132 // find_method looks up the name/signature in the local methods array
2133 Method* InstanceKlass::find_method(const Symbol* name,
2134 const Symbol* signature) const {
2135 return find_method_impl(name, signature,
2136 OverpassLookupMode::find,
2137 StaticLookupMode::find,
2138 PrivateLookupMode::find);
2139 }
2140
2141 Method* InstanceKlass::find_method_impl(const Symbol* name,
2142 const Symbol* signature,
2143 OverpassLookupMode overpass_mode,
2144 StaticLookupMode static_mode,
2145 PrivateLookupMode private_mode) const {
2146 return InstanceKlass::find_method_impl(methods(),
2147 name,
2148 signature,
2149 overpass_mode,
2150 static_mode,
2151 private_mode);
2152 }
2153
2154 // find_instance_method looks up the name/signature in the local methods array
2155 // and skips over static methods
2156 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2157 const Symbol* name,
2158 const Symbol* signature,
2159 PrivateLookupMode private_mode) {
2160 Method* const meth = InstanceKlass::find_method_impl(methods,
2161 name,
2162 signature,
2163 OverpassLookupMode::find,
2164 StaticLookupMode::skip,
2165 private_mode);
2166 assert(((meth == nullptr) || !meth->is_static()),
2167 "find_instance_method should have skipped statics");
2168 return meth;
2169 }
2170
2171 // find_instance_method looks up the name/signature in the local methods array
2172 // and skips over static methods
2173 Method* InstanceKlass::find_instance_method(const Symbol* name,
2174 const Symbol* signature,
2175 PrivateLookupMode private_mode) const {
2176 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2177 }
2178
2179 // Find looks up the name/signature in the local methods array
2180 // and filters on the overpass, static and private flags
2181 // This returns the first one found
2182 // note that the local methods array can have up to one overpass, one static
2183 // and one instance (private or not) with the same name/signature
2184 Method* InstanceKlass::find_local_method(const Symbol* name,
2185 const Symbol* signature,
2186 OverpassLookupMode overpass_mode,
2187 StaticLookupMode static_mode,
2188 PrivateLookupMode private_mode) const {
2189 return InstanceKlass::find_method_impl(methods(),
2190 name,
2191 signature,
2192 overpass_mode,
2193 static_mode,
2194 private_mode);
2195 }
2196
2197 // Find looks up the name/signature in the local methods array
2198 // and filters on the overpass, static and private flags
2199 // This returns the first one found
2200 // note that the local methods array can have up to one overpass, one static
2201 // and one instance (private or not) with the same name/signature
2202 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2203 const Symbol* name,
2204 const Symbol* signature,
2205 OverpassLookupMode overpass_mode,
2206 StaticLookupMode static_mode,
2207 PrivateLookupMode private_mode) {
2208 return InstanceKlass::find_method_impl(methods,
2209 name,
2210 signature,
2211 overpass_mode,
2212 static_mode,
2213 private_mode);
2214 }
2215
2216 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2217 const Symbol* name,
2218 const Symbol* signature) {
2219 return InstanceKlass::find_method_impl(methods,
2220 name,
2221 signature,
2222 OverpassLookupMode::find,
2223 StaticLookupMode::find,
2224 PrivateLookupMode::find);
2225 }
2226
2227 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2228 const Symbol* name,
2229 const Symbol* signature,
2230 OverpassLookupMode overpass_mode,
2231 StaticLookupMode static_mode,
2232 PrivateLookupMode private_mode) {
2233 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2234 return hit >= 0 ? methods->at(hit): nullptr;
2235 }
2236
2237 // true if method matches signature and conforms to skipping_X conditions.
2238 static bool method_matches(const Method* m,
2239 const Symbol* signature,
2240 bool skipping_overpass,
2241 bool skipping_static,
2242 bool skipping_private) {
2243 return ((m->signature() == signature) &&
2244 (!skipping_overpass || !m->is_overpass()) &&
2245 (!skipping_static || !m->is_static()) &&
2246 (!skipping_private || !m->is_private()));
2247 }
2248
2249 // Used directly for default_methods to find the index into the
2250 // default_vtable_indices, and indirectly by find_method
2251 // find_method_index looks in the local methods array to return the index
2252 // of the matching name/signature. If, overpass methods are being ignored,
2253 // the search continues to find a potential non-overpass match. This capability
2254 // is important during method resolution to prefer a static method, for example,
2255 // over an overpass method.
2256 // There is the possibility in any _method's array to have the same name/signature
2257 // for a static method, an overpass method and a local instance method
2258 // To correctly catch a given method, the search criteria may need
2259 // to explicitly skip the other two. For local instance methods, it
2260 // is often necessary to skip private methods
2261 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2262 const Symbol* name,
2263 const Symbol* signature,
2264 OverpassLookupMode overpass_mode,
2265 StaticLookupMode static_mode,
2266 PrivateLookupMode private_mode) {
2267 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2268 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2269 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2270 const int hit = quick_search(methods, name);
2271 if (hit != -1) {
2272 const Method* const m = methods->at(hit);
2273
2274 // Do linear search to find matching signature. First, quick check
2275 // for common case, ignoring overpasses if requested.
2276 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2277 return hit;
2278 }
2279
2280 // search downwards through overloaded methods
2281 int i;
2282 for (i = hit - 1; i >= 0; --i) {
2283 const Method* const m = methods->at(i);
2284 assert(m->is_method(), "must be method");
2285 if (m->name() != name) {
2286 break;
2287 }
2288 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2289 return i;
2290 }
2291 }
2292 // search upwards
2293 for (i = hit + 1; i < methods->length(); ++i) {
2294 const Method* const m = methods->at(i);
2295 assert(m->is_method(), "must be method");
2296 if (m->name() != name) {
2297 break;
2298 }
2299 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2300 return i;
2301 }
2302 }
2303 // not found
2304 #ifdef ASSERT
2305 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2306 linear_search(methods, name, signature);
2307 assert(-1 == index, "binary search should have found entry %d", index);
2308 #endif
2309 }
2310 return -1;
2311 }
2312
2313 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2314 return find_method_by_name(methods(), name, end);
2315 }
2316
2317 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2318 const Symbol* name,
2319 int* end_ptr) {
2320 assert(end_ptr != nullptr, "just checking");
2321 int start = quick_search(methods, name);
2322 int end = start + 1;
2323 if (start != -1) {
2324 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2325 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2326 *end_ptr = end;
2327 return start;
2328 }
2329 return -1;
2330 }
2331
2332 // uncached_lookup_method searches both the local class methods array and all
2333 // superclasses methods arrays, skipping any overpass methods in superclasses,
2334 // and possibly skipping private methods.
2335 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2336 const Symbol* signature,
2337 OverpassLookupMode overpass_mode,
2338 PrivateLookupMode private_mode) const {
2339 OverpassLookupMode overpass_local_mode = overpass_mode;
2340 const Klass* klass = this;
2341 while (klass != nullptr) {
2342 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2343 signature,
2344 overpass_local_mode,
2345 StaticLookupMode::find,
2346 private_mode);
2347 if (method != nullptr) {
2348 return method;
2349 }
2350 if (name == vmSymbols::object_initializer_name()) {
2351 break; // <init> is never inherited
2352 }
2353 klass = klass->super();
2354 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2355 }
2356 return nullptr;
2357 }
2358
2359 #ifdef ASSERT
2360 // search through class hierarchy and return true if this class or
2361 // one of the superclasses was redefined
2362 bool InstanceKlass::has_redefined_this_or_super() const {
2363 const Klass* klass = this;
2364 while (klass != nullptr) {
2365 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2366 return true;
2367 }
2368 klass = klass->super();
2369 }
2370 return false;
2371 }
2372 #endif
2373
2374 // lookup a method in the default methods list then in all transitive interfaces
2375 // Do NOT return private or static methods
2376 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2377 Symbol* signature) const {
2378 Method* m = nullptr;
2379 if (default_methods() != nullptr) {
2380 m = find_method(default_methods(), name, signature);
2381 }
2382 // Look up interfaces
2383 if (m == nullptr) {
2384 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2385 }
2386 return m;
2387 }
2388
2389 // lookup a method in all the interfaces that this class implements
2390 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2391 // They should only be found in the initial InterfaceMethodRef
2392 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2393 Symbol* signature,
2394 DefaultsLookupMode defaults_mode) const {
2395 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2396 int num_ifs = all_ifs->length();
2397 InstanceKlass *ik = nullptr;
2398 for (int i = 0; i < num_ifs; i++) {
2399 ik = all_ifs->at(i);
2400 Method* m = ik->lookup_method(name, signature);
2401 if (m != nullptr && m->is_public() && !m->is_static() &&
2402 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2403 return m;
2404 }
2405 }
2406 return nullptr;
2407 }
2408
2409 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2410 :_st(st), _verbose(verbose) {
2411 ResourceMark rm;
2412 _st->print("%-18s ", "KlassAddr");
2413 _st->print("%-4s ", "Size");
2414 _st->print("%-20s ", "State");
2415 _st->print("%-7s ", "Flags");
2416 _st->print("%-5s ", "ClassName");
2417 _st->cr();
2418 }
2419
2420 void PrintClassClosure::do_klass(Klass* k) {
2421 ResourceMark rm;
2422 // klass pointer
2423 _st->print(PTR_FORMAT " ", p2i(k));
2424 // klass size
2425 _st->print("%4d ", k->size());
2426 // initialization state
2427 if (k->is_instance_klass()) {
2428 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2429 } else {
2430 _st->print("%-20s ","");
2431 }
2432 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2433 char buf[10];
2434 int i = 0;
2435 if (k->has_finalizer()) buf[i++] = 'F';
2436 if (k->is_instance_klass()) {
2437 InstanceKlass* ik = InstanceKlass::cast(k);
2438 if (ik->has_final_method()) buf[i++] = 'f';
2439 if (ik->is_rewritten()) buf[i++] = 'W';
2440 if (ik->is_contended()) buf[i++] = 'C';
2441 if (ik->has_been_redefined()) buf[i++] = 'R';
2442 if (ik->is_shared()) buf[i++] = 'S';
2443 }
2444 buf[i++] = '\0';
2445 _st->print("%-7s ", buf);
2446 // klass name
2447 _st->print("%-5s ", k->external_name());
2448 // end
2449 _st->cr();
2450 if (_verbose) {
2451 k->print_on(_st);
2452 }
2453 }
2454
2455 /* jni_id_for for jfieldIds only */
2456 JNIid* InstanceKlass::jni_id_for(int offset) {
2457 MutexLocker ml(JfieldIdCreation_lock);
2458 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2459 if (probe == nullptr) {
2460 // Allocate new static field identifier
2461 probe = new JNIid(this, offset, jni_ids());
2462 set_jni_ids(probe);
2463 }
2464 return probe;
2465 }
2466
2467 u2 InstanceKlass::enclosing_method_data(int offset) const {
2468 const Array<jushort>* const inner_class_list = inner_classes();
2469 if (inner_class_list == nullptr) {
2470 return 0;
2471 }
2472 const int length = inner_class_list->length();
2473 if (length % inner_class_next_offset == 0) {
2474 return 0;
2475 }
2476 const int index = length - enclosing_method_attribute_size;
2477 assert(offset < enclosing_method_attribute_size, "invalid offset");
2478 return inner_class_list->at(index + offset);
2479 }
2480
2481 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2482 u2 method_index) {
2483 Array<jushort>* inner_class_list = inner_classes();
2484 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2485 int length = inner_class_list->length();
2486 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2487 int index = length - enclosing_method_attribute_size;
2488 inner_class_list->at_put(
2489 index + enclosing_method_class_index_offset, class_index);
2490 inner_class_list->at_put(
2491 index + enclosing_method_method_index_offset, method_index);
2492 }
2493 }
2494
2495 // Lookup or create a jmethodID.
2496 // This code is called by the VMThread and JavaThreads so the
2497 // locking has to be done very carefully to avoid deadlocks
2498 // and/or other cache consistency problems.
2499 //
2500 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2501 size_t idnum = (size_t)method_h->method_idnum();
2502 jmethodID* jmeths = methods_jmethod_ids_acquire();
2503 size_t length = 0;
2504 jmethodID id = nullptr;
2505
2506 // We use a double-check locking idiom here because this cache is
2507 // performance sensitive. In the normal system, this cache only
2508 // transitions from null to non-null which is safe because we use
2509 // release_set_methods_jmethod_ids() to advertise the new cache.
2510 // A partially constructed cache should never be seen by a racing
2511 // thread. We also use release_store() to save a new jmethodID
2512 // in the cache so a partially constructed jmethodID should never be
2513 // seen either. Cache reads of existing jmethodIDs proceed without a
2514 // lock, but cache writes of a new jmethodID requires uniqueness and
2515 // creation of the cache itself requires no leaks so a lock is
2516 // generally acquired in those two cases.
2517 //
2518 // If the RedefineClasses() API has been used, then this cache can
2519 // grow and we'll have transitions from non-null to bigger non-null.
2520 // Cache creation requires no leaks and we require safety between all
2521 // cache accesses and freeing of the old cache so a lock is generally
2522 // acquired when the RedefineClasses() API has been used.
2523
2524 if (jmeths != nullptr) {
2525 // the cache already exists
2526 if (!idnum_can_increment()) {
2527 // the cache can't grow so we can just get the current values
2528 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2529 } else {
2530 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2531 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2532 }
2533 }
2534 // implied else:
2535 // we need to allocate a cache so default length and id values are good
2536
2537 if (jmeths == nullptr || // no cache yet
2538 length <= idnum || // cache is too short
2539 id == nullptr) { // cache doesn't contain entry
2540
2541 // This function can be called by the VMThread or GC worker threads so we
2542 // have to do all things that might block on a safepoint before grabbing the lock.
2543 // Otherwise, we can deadlock with the VMThread or have a cache
2544 // consistency issue. These vars keep track of what we might have
2545 // to free after the lock is dropped.
2546 jmethodID to_dealloc_id = nullptr;
2547 jmethodID* to_dealloc_jmeths = nullptr;
2548
2549 // may not allocate new_jmeths or use it if we allocate it
2550 jmethodID* new_jmeths = nullptr;
2551 if (length <= idnum) {
2552 // allocate a new cache that might be used
2553 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2554 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2555 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2556 // cache size is stored in element[0], other elements offset by one
2557 new_jmeths[0] = (jmethodID)size;
2558 }
2559
2560 // allocate a new jmethodID that might be used
2561 {
2562 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2563 jmethodID new_id = nullptr;
2564 if (method_h->is_old() && !method_h->is_obsolete()) {
2565 // The method passed in is old (but not obsolete), we need to use the current version
2566 Method* current_method = method_with_idnum((int)idnum);
2567 assert(current_method != nullptr, "old and but not obsolete, so should exist");
2568 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2569 } else {
2570 // It is the current version of the method or an obsolete method,
2571 // use the version passed in
2572 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2573 }
2574
2575 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2576 &to_dealloc_id, &to_dealloc_jmeths);
2577 }
2578
2579 // The lock has been dropped so we can free resources.
2580 // Free up either the old cache or the new cache if we allocated one.
2581 if (to_dealloc_jmeths != nullptr) {
2582 FreeHeap(to_dealloc_jmeths);
2583 }
2584 // free up the new ID since it wasn't needed
2585 if (to_dealloc_id != nullptr) {
2586 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2587 }
2588 }
2589 return id;
2590 }
2591
2592 // Figure out how many jmethodIDs haven't been allocated, and make
2593 // sure space for them is pre-allocated. This makes getting all
2594 // method ids much, much faster with classes with more than 8
2595 // methods, and has a *substantial* effect on performance with jvmti
2596 // code that loads all jmethodIDs for all classes.
2597 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2598 int new_jmeths = 0;
2599 int length = methods()->length();
2600 for (int index = start_offset; index < length; index++) {
2601 Method* m = methods()->at(index);
2602 jmethodID id = m->find_jmethod_id_or_null();
2603 if (id == nullptr) {
2604 new_jmeths++;
2605 }
2606 }
2607 if (new_jmeths != 0) {
2608 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2609 }
2610 }
2611
2612 // Common code to fetch the jmethodID from the cache or update the
2613 // cache with the new jmethodID. This function should never do anything
2614 // that causes the caller to go to a safepoint or we can deadlock with
2615 // the VMThread or have cache consistency issues.
2616 //
2617 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2618 size_t idnum, jmethodID new_id,
2619 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2620 jmethodID** to_dealloc_jmeths_p) {
2621 assert(new_id != nullptr, "sanity check");
2622 assert(to_dealloc_id_p != nullptr, "sanity check");
2623 assert(to_dealloc_jmeths_p != nullptr, "sanity check");
2624 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2625
2626 // reacquire the cache - we are locked, single threaded or at a safepoint
2627 jmethodID* jmeths = methods_jmethod_ids_acquire();
2628 jmethodID id = nullptr;
2629 size_t length = 0;
2630
2631 if (jmeths == nullptr || // no cache yet
2632 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2633 if (jmeths != nullptr) {
2634 // copy any existing entries from the old cache
2635 for (size_t index = 0; index < length; index++) {
2636 new_jmeths[index+1] = jmeths[index+1];
2637 }
2638 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2639 }
2640 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2641 } else {
2642 // fetch jmethodID (if any) from the existing cache
2643 id = jmeths[idnum+1];
2644 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2645 }
2646 if (id == nullptr) {
2647 // No matching jmethodID in the existing cache or we have a new
2648 // cache or we just grew the cache. This cache write is done here
2649 // by the first thread to win the foot race because a jmethodID
2650 // needs to be unique once it is generally available.
2651 id = new_id;
2652
2653 // The jmethodID cache can be read while unlocked so we have to
2654 // make sure the new jmethodID is complete before installing it
2655 // in the cache.
2656 Atomic::release_store(&jmeths[idnum+1], id);
2657 } else {
2658 *to_dealloc_id_p = new_id; // save new id for later delete
2659 }
2660 return id;
2661 }
2662
2663
2664 // Common code to get the jmethodID cache length and the jmethodID
2665 // value at index idnum if there is one.
2666 //
2667 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2668 size_t idnum, size_t *length_p, jmethodID* id_p) {
2669 assert(cache != nullptr, "sanity check");
2670 assert(length_p != nullptr, "sanity check");
2671 assert(id_p != nullptr, "sanity check");
2672
2673 // cache size is stored in element[0], other elements offset by one
2674 *length_p = (size_t)cache[0];
2675 if (*length_p <= idnum) { // cache is too short
2676 *id_p = nullptr;
2677 } else {
2678 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2679 }
2680 }
2681
2682
2683 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2684 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2685 size_t idnum = (size_t)method->method_idnum();
2686 jmethodID* jmeths = methods_jmethod_ids_acquire();
2687 size_t length; // length assigned as debugging crumb
2688 jmethodID id = nullptr;
2689 if (jmeths != nullptr && // If there is a cache
2690 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2691 id = jmeths[idnum+1]; // Look up the id (may be null)
2692 }
2693 return id;
2694 }
2695
2696 inline DependencyContext InstanceKlass::dependencies() {
2697 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2698 return dep_context;
2699 }
2700
2701 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2702 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2703 }
2704
2705 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2706 dependencies().add_dependent_nmethod(nm);
2707 }
2708
2709 void InstanceKlass::clean_dependency_context() {
2710 dependencies().clean_unloading_dependents();
2711 }
2712
2713 #ifndef PRODUCT
2714 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2715 dependencies().print_dependent_nmethods(verbose);
2716 }
2717
2718 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2719 return dependencies().is_dependent_nmethod(nm);
2720 }
2721 #endif //PRODUCT
2722
2723 void InstanceKlass::clean_weak_instanceklass_links() {
2724 clean_implementors_list();
2725 clean_method_data();
2726 }
2727
2728 void InstanceKlass::clean_implementors_list() {
2729 assert(is_loader_alive(), "this klass should be live");
2730 if (is_interface()) {
2731 assert (ClassUnloading, "only called for ClassUnloading");
2732 for (;;) {
2733 // Use load_acquire due to competing with inserts
2734 InstanceKlass* volatile* iklass = adr_implementor();
2735 assert(iklass != nullptr, "Klass must not be null");
2736 InstanceKlass* impl = Atomic::load_acquire(iklass);
2737 if (impl != nullptr && !impl->is_loader_alive()) {
2738 // null this field, might be an unloaded instance klass or null
2739 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2740 // Successfully unlinking implementor.
2741 if (log_is_enabled(Trace, class, unload)) {
2742 ResourceMark rm;
2743 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2744 }
2745 return;
2746 }
2747 } else {
2748 return;
2749 }
2750 }
2751 }
2752 }
2753
2754 void InstanceKlass::clean_method_data() {
2755 for (int m = 0; m < methods()->length(); m++) {
2756 MethodData* mdo = methods()->at(m)->method_data();
2757 if (mdo != nullptr) {
2758 ConditionalMutexLocker ml(mdo->extra_data_lock(), !SafepointSynchronize::is_at_safepoint());
2759 mdo->clean_method_data(/*always_clean*/false);
2760 }
2761 }
2762 }
2763
2764 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2765 Klass::metaspace_pointers_do(it);
2766
2767 if (log_is_enabled(Trace, cds)) {
2768 ResourceMark rm;
2769 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2770 }
2771
2772 it->push(&_annotations);
2773 it->push((Klass**)&_array_klasses);
2774 if (!is_rewritten()) {
2775 it->push(&_constants, MetaspaceClosure::_writable);
2776 } else {
2777 it->push(&_constants);
2778 }
2779 it->push(&_inner_classes);
2780 #if INCLUDE_JVMTI
2781 it->push(&_previous_versions);
2782 #endif
2783 #if INCLUDE_CDS
2784 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2785 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2786 // be writable. The length check on the _methods is necessary because classes which
2787 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2788 if (_methods != nullptr && _methods->length() > 0 &&
2789 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2790 // To handle jsr bytecode, new Method* maybe stored into _methods
2791 it->push(&_methods, MetaspaceClosure::_writable);
2792 } else {
2793 #endif
2794 it->push(&_methods);
2795 #if INCLUDE_CDS
2796 }
2797 #endif
2798 it->push(&_default_methods);
2799 it->push(&_local_interfaces);
2800 it->push(&_transitive_interfaces);
2801 it->push(&_method_ordering);
2802 if (!is_rewritten()) {
2803 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2804 } else {
2805 it->push(&_default_vtable_indices);
2806 }
2807
2808 it->push(&_fieldinfo_stream);
2809 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2810 it->push(&_fields_status, MetaspaceClosure::_writable);
2811
2812 if (itable_length() > 0) {
2813 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2814 int method_table_offset_in_words = ioe->offset()/wordSize;
2815 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2816
2817 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2818 / itableOffsetEntry::size();
2819
2820 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2821 if (ioe->interface_klass() != nullptr) {
2822 it->push(ioe->interface_klass_addr());
2823 itableMethodEntry* ime = ioe->first_method_entry(this);
2824 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2825 for (int index = 0; index < n; index ++) {
2826 it->push(ime[index].method_addr());
2827 }
2828 }
2829 }
2830 }
2831
2832 it->push(&_nest_members);
2833 it->push(&_permitted_subclasses);
2834 it->push(&_preload_classes);
2835 it->push(&_record_components);
2836
2837 it->push(&_inline_type_field_klasses, MetaspaceClosure::_writable);
2838 }
2839
2840 #if INCLUDE_CDS
2841 void InstanceKlass::remove_unshareable_info() {
2842
2843 if (is_linked()) {
2844 assert(can_be_verified_at_dumptime(), "must be");
2845 // Remember this so we can avoid walking the hierarchy at runtime.
2846 set_verified_at_dump_time();
2847 }
2848
2849 Klass::remove_unshareable_info();
2850
2851 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2852 // Classes are attempted to link during dumping and may fail,
2853 // but these classes are still in the dictionary and class list in CLD.
2854 // If the class has failed verification, there is nothing else to remove.
2855 return;
2856 }
2857
2858 // Reset to the 'allocated' state to prevent any premature accessing to
2859 // a shared class at runtime while the class is still being loaded and
2860 // restored. A class' init_state is set to 'loaded' at runtime when it's
2861 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2862 _init_state = allocated;
2863
2864 { // Otherwise this needs to take out the Compile_lock.
2865 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2866 init_implementor();
2867 }
2868
2869 constants()->remove_unshareable_info();
2870
2871 for (int i = 0; i < methods()->length(); i++) {
2872 Method* m = methods()->at(i);
2873 m->remove_unshareable_info();
2874 }
2875
2876 // do array classes also.
2877 if (array_klasses() != nullptr) {
2878 array_klasses()->remove_unshareable_info();
2879 }
2880
2881 // These are not allocated from metaspace. They are safe to set to nullptr.
2882 _source_debug_extension = nullptr;
2883 _dep_context = nullptr;
2884 _osr_nmethods_head = nullptr;
2885 #if INCLUDE_JVMTI
2886 _breakpoints = nullptr;
2887 _previous_versions = nullptr;
2888 _cached_class_file = nullptr;
2889 _jvmti_cached_class_field_map = nullptr;
2890 #endif
2891
2892 _init_thread = nullptr;
2893 _methods_jmethod_ids = nullptr;
2894 _jni_ids = nullptr;
2895 _oop_map_cache = nullptr;
2896 // clear _nest_host to ensure re-load at runtime
2897 _nest_host = nullptr;
2898 init_shared_package_entry();
2899 _dep_context_last_cleaned = 0;
2900 _init_monitor = nullptr;
2901
2902 remove_unshareable_flags();
2903 }
2904
2905 void InstanceKlass::remove_unshareable_flags() {
2906 // clear all the flags/stats that shouldn't be in the archived version
2907 assert(!is_scratch_class(), "must be");
2908 assert(!has_been_redefined(), "must be");
2909 #if INCLUDE_JVMTI
2910 set_is_being_redefined(false);
2911 #endif
2912 set_has_resolved_methods(false);
2913 }
2914
2915 void InstanceKlass::remove_java_mirror() {
2916 Klass::remove_java_mirror();
2917
2918 // do array classes also.
2919 if (array_klasses() != nullptr) {
2920 array_klasses()->remove_java_mirror();
2921 }
2922 }
2923
2924 void InstanceKlass::init_shared_package_entry() {
2925 assert(CDSConfig::is_dumping_archive(), "must be");
2926 #if !INCLUDE_CDS_JAVA_HEAP
2927 _package_entry = nullptr;
2928 #else
2929 if (CDSConfig::is_dumping_full_module_graph()) {
2930 if (is_shared_unregistered_class()) {
2931 _package_entry = nullptr;
2932 } else {
2933 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2934 }
2935 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2936 CDSConfig::is_loading_full_module_graph() &&
2937 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2938 // _package_entry is an archived package in the base archive. Leave it as is.
2939 } else {
2940 _package_entry = nullptr;
2941 }
2942 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2943 #endif
2944 }
2945
2946 void InstanceKlass::compute_has_loops_flag_for_methods() {
2947 Array<Method*>* methods = this->methods();
2948 for (int index = 0; index < methods->length(); ++index) {
2949 Method* m = methods->at(index);
2950 if (!m->is_overpass()) { // work around JDK-8305771
2951 m->compute_has_loops_flag();
2952 }
2953 }
2954 }
2955
2956 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2957 PackageEntry* pkg_entry, TRAPS) {
2958 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2959 // before the InstanceKlass is added to the SystemDictionary. Make
2960 // sure the current state is <loaded.
2961 assert(!is_loaded(), "invalid init state");
2962 assert(!shared_loading_failed(), "Must not try to load failed class again");
2963 set_package(loader_data, pkg_entry, CHECK);
2964 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2965
2966 if (is_inline_klass()) {
2967 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2968 }
2969
2970 Array<Method*>* methods = this->methods();
2971 int num_methods = methods->length();
2972 for (int index = 0; index < num_methods; ++index) {
2973 methods->at(index)->restore_unshareable_info(CHECK);
2974 }
2975 #if INCLUDE_JVMTI
2976 if (JvmtiExport::has_redefined_a_class()) {
2977 // Reinitialize vtable because RedefineClasses may have changed some
2978 // entries in this vtable for super classes so the CDS vtable might
2979 // point to old or obsolete entries. RedefineClasses doesn't fix up
2980 // vtables in the shared system dictionary, only the main one.
2981 // It also redefines the itable too so fix that too.
2982 // First fix any default methods that point to a super class that may
2983 // have been redefined.
2984 bool trace_name_printed = false;
2985 adjust_default_methods(&trace_name_printed);
2986 vtable().initialize_vtable();
2987 itable().initialize_itable();
2988 }
2989 #endif
2990
2991 // restore constant pool resolved references
2992 constants()->restore_unshareable_info(CHECK);
2993
2994 if (array_klasses() != nullptr) {
2995 // To get a consistent list of classes we need MultiArray_lock to ensure
2996 // array classes aren't observed while they are being restored.
2997 MutexLocker ml(MultiArray_lock);
2998 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
2999 // Array classes have null protection domain.
3000 // --> see ArrayKlass::complete_create_array_klass()
3001 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3002 }
3003
3004 // Initialize @ValueBased class annotation
3005 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
3006 set_is_value_based();
3007 }
3008
3009 // restore the monitor
3010 _init_monitor = create_init_monitor("InstanceKlassInitMonitorRestored_lock");
3011 }
3012
3013 // Check if a class or any of its supertypes has a version older than 50.
3014 // CDS will not perform verification of old classes during dump time because
3015 // without changing the old verifier, the verification constraint cannot be
3016 // retrieved during dump time.
3017 // Verification of archived old classes will be performed during run time.
3018 bool InstanceKlass::can_be_verified_at_dumptime() const {
3019 if (MetaspaceShared::is_in_shared_metaspace(this)) {
3020 // This is a class that was dumped into the base archive, so we know
3021 // it was verified at dump time.
3022 return true;
3023 }
3024 if (major_version() < 50 /*JAVA_6_VERSION*/) {
3025 return false;
3026 }
3027 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
3028 return false;
3029 }
3030 Array<InstanceKlass*>* interfaces = local_interfaces();
3031 int len = interfaces->length();
3032 for (int i = 0; i < len; i++) {
3033 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3034 return false;
3035 }
3036 }
3037 return true;
3038 }
3039
3040 bool InstanceKlass::methods_contain_jsr_bytecode() const {
3041 Thread* thread = Thread::current();
3042 for (int i = 0; i < _methods->length(); i++) {
3043 methodHandle m(thread, _methods->at(i));
3044 BytecodeStream bcs(m);
3045 while (!bcs.is_last_bytecode()) {
3046 Bytecodes::Code opcode = bcs.next();
3047 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
3048 return true;
3049 }
3050 }
3051 }
3052 return false;
3053 }
3054 #endif // INCLUDE_CDS
3055
3056 #if INCLUDE_JVMTI
3057 static void clear_all_breakpoints(Method* m) {
3058 m->clear_all_breakpoints();
3059 }
3060 #endif
3061
3062 void InstanceKlass::unload_class(InstanceKlass* ik) {
3063 // Release dependencies.
3064 ik->dependencies().remove_all_dependents();
3065
3066 // notify the debugger
3067 if (JvmtiExport::should_post_class_unload()) {
3068 JvmtiExport::post_class_unload(ik);
3069 }
3070
3071 // notify ClassLoadingService of class unload
3072 ClassLoadingService::notify_class_unloaded(ik);
3073
3074 SystemDictionaryShared::handle_class_unloading(ik);
3075
3076 if (log_is_enabled(Info, class, unload)) {
3077 ResourceMark rm;
3078 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3079 }
3080
3081 Events::log_class_unloading(Thread::current(), ik);
3082
3083 #if INCLUDE_JFR
3084 assert(ik != nullptr, "invariant");
3085 EventClassUnload event;
3086 event.set_unloadedClass(ik);
3087 event.set_definingClassLoader(ik->class_loader_data());
3088 event.commit();
3089 #endif
3090 }
3091
3092 static void method_release_C_heap_structures(Method* m) {
3093 m->release_C_heap_structures();
3094 }
3095
3096 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3097 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3098 // Clean up C heap
3099 Klass::release_C_heap_structures();
3100
3101 // Deallocate and call destructors for MDO mutexes
3102 if (release_sub_metadata) {
3103 methods_do(method_release_C_heap_structures);
3104 }
3105
3106 // Destroy the init_monitor
3107 delete _init_monitor;
3108
3109 // Deallocate oop map cache
3110 if (_oop_map_cache != nullptr) {
3111 delete _oop_map_cache;
3112 _oop_map_cache = nullptr;
3113 }
3114
3115 // Deallocate JNI identifiers for jfieldIDs
3116 JNIid::deallocate(jni_ids());
3117 set_jni_ids(nullptr);
3118
3119 jmethodID* jmeths = methods_jmethod_ids_acquire();
3120 if (jmeths != (jmethodID*)nullptr) {
3121 release_set_methods_jmethod_ids(nullptr);
3122 FreeHeap(jmeths);
3123 }
3124
3125 assert(_dep_context == nullptr,
3126 "dependencies should already be cleaned");
3127
3128 #if INCLUDE_JVMTI
3129 // Deallocate breakpoint records
3130 if (breakpoints() != 0x0) {
3131 methods_do(clear_all_breakpoints);
3132 assert(breakpoints() == 0x0, "should have cleared breakpoints");
3133 }
3134
3135 // deallocate the cached class file
3136 if (_cached_class_file != nullptr) {
3137 os::free(_cached_class_file);
3138 _cached_class_file = nullptr;
3139 }
3140 #endif
3141
3142 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3143
3144 if (release_sub_metadata) {
3145 constants()->release_C_heap_structures();
3146 }
3147 }
3148
3149 // The constant pool is on stack if any of the methods are executing or
3150 // referenced by handles.
3151 bool InstanceKlass::on_stack() const {
3152 return _constants->on_stack();
3153 }
3154
3155 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3156 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3157 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3158
3159 // minor and major version numbers of class file
3160 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3161 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3162 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3163 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3164
3165 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3166 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3167 if (ik->constants()->version() == version) {
3168 return ik;
3169 }
3170 }
3171 return nullptr;
3172 }
3173
3174 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3175 if (array == nullptr) {
3176 _source_debug_extension = nullptr;
3177 } else {
3178 // Adding one to the attribute length in order to store a null terminator
3179 // character could cause an overflow because the attribute length is
3180 // already coded with an u4 in the classfile, but in practice, it's
3181 // unlikely to happen.
3182 assert((length+1) > length, "Overflow checking");
3183 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3184 for (int i = 0; i < length; i++) {
3185 sde[i] = array[i];
3186 }
3187 sde[length] = '\0';
3188 _source_debug_extension = sde;
3189 }
3190 }
3191
3192 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3193 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3194 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3195
3196 const char* InstanceKlass::signature_name() const {
3197 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3198 }
3199
3200 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3201 // Get the internal name as a c string
3202 const char* src = (const char*) (name()->as_C_string());
3203 const int src_length = (int)strlen(src);
3204
3205 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3206
3207 // Add L or Q as type indicator
3208 int dest_index = 0;
3209 dest[dest_index++] = c;
3210
3211 // Add the actual class name
3212 for (int src_index = 0; src_index < src_length; ) {
3213 dest[dest_index++] = src[src_index++];
3214 }
3215
3216 if (is_hidden()) { // Replace the last '+' with a '.'.
3217 for (int index = (int)src_length; index > 0; index--) {
3218 if (dest[index] == '+') {
3219 dest[index] = JVM_SIGNATURE_DOT;
3220 break;
3221 }
3222 }
3223 }
3224
3225 // Add the semicolon and the null
3226 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3227 dest[dest_index] = '\0';
3228 return dest;
3229 }
3230
3231 ModuleEntry* InstanceKlass::module() const {
3232 if (is_hidden() &&
3233 in_unnamed_package() &&
3234 class_loader_data()->has_class_mirror_holder()) {
3235 // For a non-strong hidden class defined to an unnamed package,
3236 // its (class held) CLD will not have an unnamed module created for it.
3237 // Two choices to find the correct ModuleEntry:
3238 // 1. If hidden class is within a nest, use nest host's module
3239 // 2. Find the unnamed module off from the class loader
3240 // For now option #2 is used since a nest host is not set until
3241 // after the instance class is created in jvm_lookup_define_class().
3242 if (class_loader_data()->is_boot_class_loader_data()) {
3243 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3244 } else {
3245 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3246 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3247 return java_lang_Module::module_entry(module);
3248 }
3249 }
3250
3251 // Class is in a named package
3252 if (!in_unnamed_package()) {
3253 return _package_entry->module();
3254 }
3255
3256 // Class is in an unnamed package, return its loader's unnamed module
3257 return class_loader_data()->unnamed_module();
3258 }
3259
3260 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3261
3262 // ensure java/ packages only loaded by boot or platform builtin loaders
3263 // not needed for shared class since CDS does not archive prohibited classes.
3264 if (!is_shared()) {
3265 check_prohibited_package(name(), loader_data, CHECK);
3266 }
3267
3268 if (is_shared() && _package_entry != nullptr) {
3269 if (CDSConfig::is_loading_full_module_graph() && _package_entry == pkg_entry) {
3270 // we can use the saved package
3271 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3272 return;
3273 } else {
3274 _package_entry = nullptr;
3275 }
3276 }
3277
3278 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3279 // it returns, so we need to decrement it when the current function exits.
3280 TempNewSymbol from_class_name =
3281 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3282
3283 Symbol* pkg_name;
3284 if (pkg_entry != nullptr) {
3285 pkg_name = pkg_entry->name();
3286 } else {
3287 pkg_name = from_class_name;
3288 }
3289
3290 if (pkg_name != nullptr && loader_data != nullptr) {
3291
3292 // Find in class loader's package entry table.
3293 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3294
3295 // If the package name is not found in the loader's package
3296 // entry table, it is an indication that the package has not
3297 // been defined. Consider it defined within the unnamed module.
3298 if (_package_entry == nullptr) {
3299
3300 if (!ModuleEntryTable::javabase_defined()) {
3301 // Before java.base is defined during bootstrapping, define all packages in
3302 // the java.base module. If a non-java.base package is erroneously placed
3303 // in the java.base module it will be caught later when java.base
3304 // is defined by ModuleEntryTable::verify_javabase_packages check.
3305 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3306 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3307 } else {
3308 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3309 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3310 }
3311
3312 // A package should have been successfully created
3313 DEBUG_ONLY(ResourceMark rm(THREAD));
3314 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3315 name()->as_C_string(), loader_data->loader_name_and_id());
3316 }
3317
3318 if (log_is_enabled(Debug, module)) {
3319 ResourceMark rm(THREAD);
3320 ModuleEntry* m = _package_entry->module();
3321 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3322 external_name(),
3323 pkg_name->as_C_string(),
3324 loader_data->loader_name_and_id(),
3325 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3326 }
3327 } else {
3328 ResourceMark rm(THREAD);
3329 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3330 external_name(),
3331 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3332 UNNAMED_MODULE);
3333 }
3334 }
3335
3336 // Function set_classpath_index ensures that for a non-null _package_entry
3337 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3338 // It then sets the classpath_index in the package entry record.
3339 //
3340 // The classpath_index field is used to find the entry on the boot loader class
3341 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3342 // in an unnamed module. It is also used to indicate (for all packages whose
3343 // classes are loaded by the boot loader) that at least one of the package's
3344 // classes has been loaded.
3345 void InstanceKlass::set_classpath_index(s2 path_index) {
3346 if (_package_entry != nullptr) {
3347 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3348 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3349 assert(path_index != -1, "Unexpected classpath_index");
3350 _package_entry->set_classpath_index(path_index);
3351 }
3352 }
3353
3354 // different versions of is_same_class_package
3355
3356 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3357 oop classloader1 = this->class_loader();
3358 PackageEntry* classpkg1 = this->package();
3359 if (class2->is_objArray_klass()) {
3360 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3361 }
3362
3363 oop classloader2;
3364 PackageEntry* classpkg2;
3365 if (class2->is_instance_klass()) {
3366 classloader2 = class2->class_loader();
3367 classpkg2 = class2->package();
3368 } else {
3369 assert(class2->is_typeArray_klass(), "should be type array");
3370 classloader2 = nullptr;
3371 classpkg2 = nullptr;
3372 }
3373
3374 // Same package is determined by comparing class loader
3375 // and package entries. Both must be the same. This rule
3376 // applies even to classes that are defined in the unnamed
3377 // package, they still must have the same class loader.
3378 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3379 return true;
3380 }
3381
3382 return false;
3383 }
3384
3385 // return true if this class and other_class are in the same package. Classloader
3386 // and classname information is enough to determine a class's package
3387 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3388 const Symbol* other_class_name) const {
3389 if (class_loader() != other_class_loader) {
3390 return false;
3391 }
3392 if (name()->fast_compare(other_class_name) == 0) {
3393 return true;
3394 }
3395
3396 {
3397 ResourceMark rm;
3398
3399 bool bad_class_name = false;
3400 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3401 if (bad_class_name) {
3402 return false;
3403 }
3404 // Check that package_from_class_name() returns null, not "", if there is no package.
3405 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3406
3407 const Symbol* const this_package_name =
3408 this->package() != nullptr ? this->package()->name() : nullptr;
3409
3410 if (this_package_name == nullptr || other_pkg == nullptr) {
3411 // One of the two doesn't have a package. Only return true if the other
3412 // one also doesn't have a package.
3413 return this_package_name == other_pkg;
3414 }
3415
3416 // Check if package is identical
3417 return this_package_name->fast_compare(other_pkg) == 0;
3418 }
3419 }
3420
3421 static bool is_prohibited_package_slow(Symbol* class_name) {
3422 // Caller has ResourceMark
3423 int length;
3424 jchar* unicode = class_name->as_unicode(length);
3425 return (length >= 5 &&
3426 unicode[0] == 'j' &&
3427 unicode[1] == 'a' &&
3428 unicode[2] == 'v' &&
3429 unicode[3] == 'a' &&
3430 unicode[4] == '/');
3431 }
3432
3433 // Only boot and platform class loaders can define classes in "java/" packages.
3434 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3435 ClassLoaderData* loader_data,
3436 TRAPS) {
3437 if (!loader_data->is_boot_class_loader_data() &&
3438 !loader_data->is_platform_class_loader_data() &&
3439 class_name != nullptr && class_name->utf8_length() >= 5) {
3440 ResourceMark rm(THREAD);
3441 bool prohibited;
3442 const u1* base = class_name->base();
3443 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3444 prohibited = is_prohibited_package_slow(class_name);
3445 } else {
3446 char* name = class_name->as_C_string();
3447 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3448 }
3449 if (prohibited) {
3450 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3451 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3452 char* name = pkg_name->as_C_string();
3453 const char* class_loader_name = loader_data->loader_name_and_id();
3454 StringUtils::replace_no_expand(name, "/", ".");
3455 const char* msg_text1 = "Class loader (instance of): ";
3456 const char* msg_text2 = " tried to load prohibited package name: ";
3457 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3458 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3459 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3460 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3461 }
3462 }
3463 return;
3464 }
3465
3466 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3467 constantPoolHandle i_cp(THREAD, constants());
3468 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3469 int ioff = iter.inner_class_info_index();
3470 if (ioff != 0) {
3471 // Check to see if the name matches the class we're looking for
3472 // before attempting to find the class.
3473 if (i_cp->klass_name_at_matches(this, ioff)) {
3474 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3475 if (this == inner_klass) {
3476 *ooff = iter.outer_class_info_index();
3477 *noff = iter.inner_name_index();
3478 return true;
3479 }
3480 }
3481 }
3482 }
3483 return false;
3484 }
3485
3486 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3487 InstanceKlass* outer_klass = nullptr;
3488 *inner_is_member = false;
3489 int ooff = 0, noff = 0;
3490 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3491 if (has_inner_classes_attr) {
3492 constantPoolHandle i_cp(THREAD, constants());
3493 if (ooff != 0) {
3494 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3495 if (!ok->is_instance_klass()) {
3496 // If the outer class is not an instance klass then it cannot have
3497 // declared any inner classes.
3498 ResourceMark rm(THREAD);
3499 Exceptions::fthrow(
3500 THREAD_AND_LOCATION,
3501 vmSymbols::java_lang_IncompatibleClassChangeError(),
3502 "%s and %s disagree on InnerClasses attribute",
3503 ok->external_name(),
3504 external_name());
3505 return nullptr;
3506 }
3507 outer_klass = InstanceKlass::cast(ok);
3508 *inner_is_member = true;
3509 }
3510 if (nullptr == outer_klass) {
3511 // It may be a local class; try for that.
3512 int encl_method_class_idx = enclosing_method_class_index();
3513 if (encl_method_class_idx != 0) {
3514 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3515 outer_klass = InstanceKlass::cast(ok);
3516 *inner_is_member = false;
3517 }
3518 }
3519 }
3520
3521 // If no inner class attribute found for this class.
3522 if (nullptr == outer_klass) return nullptr;
3523
3524 // Throws an exception if outer klass has not declared k as an inner klass
3525 // We need evidence that each klass knows about the other, or else
3526 // the system could allow a spoof of an inner class to gain access rights.
3527 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3528 return outer_klass;
3529 }
3530
3531 jint InstanceKlass::compute_modifier_flags() const {
3532 jint access = access_flags().as_int();
3533
3534 // But check if it happens to be member class.
3535 InnerClassesIterator iter(this);
3536 for (; !iter.done(); iter.next()) {
3537 int ioff = iter.inner_class_info_index();
3538 // Inner class attribute can be zero, skip it.
3539 // Strange but true: JVM spec. allows null inner class refs.
3540 if (ioff == 0) continue;
3541
3542 // only look at classes that are already loaded
3543 // since we are looking for the flags for our self.
3544 Symbol* inner_name = constants()->klass_name_at(ioff);
3545 if (name() == inner_name) {
3546 // This is really a member class.
3547 access = iter.inner_access_flags();
3548 break;
3549 }
3550 }
3551 return (access & JVM_ACC_WRITTEN_FLAGS);
3552 }
3553
3554 jint InstanceKlass::jvmti_class_status() const {
3555 jint result = 0;
3556
3557 if (is_linked()) {
3558 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3559 }
3560
3561 if (is_initialized()) {
3562 assert(is_linked(), "Class status is not consistent");
3563 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3564 }
3565 if (is_in_error_state()) {
3566 result |= JVMTI_CLASS_STATUS_ERROR;
3567 }
3568 return result;
3569 }
3570
3571 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3572 bool implements_interface; // initialized by method_at_itable_or_null
3573 Method* m = method_at_itable_or_null(holder, index,
3574 implements_interface); // out parameter
3575 if (m != nullptr) {
3576 assert(implements_interface, "sanity");
3577 return m;
3578 } else if (implements_interface) {
3579 // Throw AbstractMethodError since corresponding itable slot is empty.
3580 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3581 } else {
3582 // If the interface isn't implemented by the receiver class,
3583 // the VM should throw IncompatibleClassChangeError.
3584 ResourceMark rm(THREAD);
3585 stringStream ss;
3586 bool same_module = (module() == holder->module());
3587 ss.print("Receiver class %s does not implement "
3588 "the interface %s defining the method to be called "
3589 "(%s%s%s)",
3590 external_name(), holder->external_name(),
3591 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3592 (same_module) ? "" : "; ",
3593 (same_module) ? "" : holder->class_in_module_of_loader());
3594 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3595 }
3596 }
3597
3598 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3599 klassItable itable(this);
3600 for (int i = 0; i < itable.size_offset_table(); i++) {
3601 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3602 if (offset_entry->interface_klass() == holder) {
3603 implements_interface = true;
3604 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3605 Method* m = ime[index].method();
3606 return m;
3607 }
3608 }
3609 implements_interface = false;
3610 return nullptr; // offset entry not found
3611 }
3612
3613 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3614 assert(is_linked(), "required");
3615 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3616 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3617
3618 int vtable_index = Method::invalid_vtable_index;
3619 Symbol* name = intf_method->name();
3620 Symbol* signature = intf_method->signature();
3621
3622 // First check in default method array
3623 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3624 int index = find_method_index(default_methods(),
3625 name, signature,
3626 Klass::OverpassLookupMode::find,
3627 Klass::StaticLookupMode::find,
3628 Klass::PrivateLookupMode::find);
3629 if (index >= 0) {
3630 vtable_index = default_vtable_indices()->at(index);
3631 }
3632 }
3633 if (vtable_index == Method::invalid_vtable_index) {
3634 // get vtable_index for miranda methods
3635 klassVtable vt = vtable();
3636 vtable_index = vt.index_of_miranda(name, signature);
3637 }
3638 return vtable_index;
3639 }
3640
3641 #if INCLUDE_JVMTI
3642 // update default_methods for redefineclasses for methods that are
3643 // not yet in the vtable due to concurrent subclass define and superinterface
3644 // redefinition
3645 // Note: those in the vtable, should have been updated via adjust_method_entries
3646 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3647 // search the default_methods for uses of either obsolete or EMCP methods
3648 if (default_methods() != nullptr) {
3649 for (int index = 0; index < default_methods()->length(); index ++) {
3650 Method* old_method = default_methods()->at(index);
3651 if (old_method == nullptr || !old_method->is_old()) {
3652 continue; // skip uninteresting entries
3653 }
3654 assert(!old_method->is_deleted(), "default methods may not be deleted");
3655 Method* new_method = old_method->get_new_method();
3656 default_methods()->at_put(index, new_method);
3657
3658 if (log_is_enabled(Info, redefine, class, update)) {
3659 ResourceMark rm;
3660 if (!(*trace_name_printed)) {
3661 log_info(redefine, class, update)
3662 ("adjust: klassname=%s default methods from name=%s",
3663 external_name(), old_method->method_holder()->external_name());
3664 *trace_name_printed = true;
3665 }
3666 log_debug(redefine, class, update, vtables)
3667 ("default method update: %s(%s) ",
3668 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3669 }
3670 }
3671 }
3672 }
3673 #endif // INCLUDE_JVMTI
3674
3675 // On-stack replacement stuff
3676 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3677 assert_lock_strong(CompiledMethod_lock);
3678 #ifndef PRODUCT
3679 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3680 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3681 "redundant OSR recompilation detected. memory leak in CodeCache!");
3682 #endif
3683 // only one compilation can be active
3684 assert(n->is_osr_method(), "wrong kind of nmethod");
3685 n->set_osr_link(osr_nmethods_head());
3686 set_osr_nmethods_head(n);
3687 // Raise the highest osr level if necessary
3688 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3689
3690 // Get rid of the osr methods for the same bci that have lower levels.
3691 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3692 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3693 if (inv != nullptr && inv->is_in_use()) {
3694 inv->make_not_entrant();
3695 }
3696 }
3697 }
3698
3699 // Remove osr nmethod from the list. Return true if found and removed.
3700 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3701 // This is a short non-blocking critical region, so the no safepoint check is ok.
3702 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3703 assert(n->is_osr_method(), "wrong kind of nmethod");
3704 nmethod* last = nullptr;
3705 nmethod* cur = osr_nmethods_head();
3706 int max_level = CompLevel_none; // Find the max comp level excluding n
3707 Method* m = n->method();
3708 // Search for match
3709 bool found = false;
3710 while(cur != nullptr && cur != n) {
3711 if (m == cur->method()) {
3712 // Find max level before n
3713 max_level = MAX2(max_level, cur->comp_level());
3714 }
3715 last = cur;
3716 cur = cur->osr_link();
3717 }
3718 nmethod* next = nullptr;
3719 if (cur == n) {
3720 found = true;
3721 next = cur->osr_link();
3722 if (last == nullptr) {
3723 // Remove first element
3724 set_osr_nmethods_head(next);
3725 } else {
3726 last->set_osr_link(next);
3727 }
3728 }
3729 n->set_osr_link(nullptr);
3730 cur = next;
3731 while (cur != nullptr) {
3732 // Find max level after n
3733 if (m == cur->method()) {
3734 max_level = MAX2(max_level, cur->comp_level());
3735 }
3736 cur = cur->osr_link();
3737 }
3738 m->set_highest_osr_comp_level(max_level);
3739 return found;
3740 }
3741
3742 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3743 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3744 nmethod* osr = osr_nmethods_head();
3745 int found = 0;
3746 while (osr != nullptr) {
3747 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3748 if (osr->method() == m) {
3749 deopt_scope->mark(osr);
3750 found++;
3751 }
3752 osr = osr->osr_link();
3753 }
3754 return found;
3755 }
3756
3757 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3758 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3759 nmethod* osr = osr_nmethods_head();
3760 nmethod* best = nullptr;
3761 while (osr != nullptr) {
3762 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3763 // There can be a time when a c1 osr method exists but we are waiting
3764 // for a c2 version. When c2 completes its osr nmethod we will trash
3765 // the c1 version and only be able to find the c2 version. However
3766 // while we overflow in the c1 code at back branches we don't want to
3767 // try and switch to the same code as we are already running
3768
3769 if (osr->method() == m &&
3770 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3771 if (match_level) {
3772 if (osr->comp_level() == comp_level) {
3773 // Found a match - return it.
3774 return osr;
3775 }
3776 } else {
3777 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3778 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3779 // Found the best possible - return it.
3780 return osr;
3781 }
3782 best = osr;
3783 }
3784 }
3785 }
3786 osr = osr->osr_link();
3787 }
3788
3789 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3790 if (best != nullptr && best->comp_level() >= comp_level) {
3791 return best;
3792 }
3793 return nullptr;
3794 }
3795
3796 // -----------------------------------------------------------------------------------------------------
3797 // Printing
3798
3799 #define BULLET " - "
3800
3801 static const char* state_names[] = {
3802 "allocated", "loaded", "being_linked", "linked", "being_initialized", "fully_initialized", "initialization_error"
3803 };
3804
3805 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3806 ResourceMark rm;
3807 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3808 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3809 for (int i = 0; i < len; i++) {
3810 intptr_t e = start[i];
3811 st->print("%d : " INTPTR_FORMAT, i, e);
3812 if (forward_refs[i] != 0) {
3813 int from = forward_refs[i];
3814 int off = (int) start[from];
3815 st->print(" (offset %d <= [%d])", off, from);
3816 }
3817 if (MetaspaceObj::is_valid((Metadata*)e)) {
3818 st->print(" ");
3819 ((Metadata*)e)->print_value_on(st);
3820 } else if (self != nullptr && e > 0 && e < 0x10000) {
3821 address location = self + e;
3822 int index = (int)((intptr_t*)location - start);
3823 st->print(" (offset %d => [%d])", (int)e, index);
3824 if (index >= 0 && index < len)
3825 forward_refs[index] = i;
3826 }
3827 st->cr();
3828 }
3829 }
3830
3831 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3832 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3833 }
3834
3835 template<typename T>
3836 static void print_array_on(outputStream* st, Array<T>* array) {
3837 if (array == nullptr) { st->print_cr("nullptr"); return; }
3838 array->print_value_on(st); st->cr();
3839 if (Verbose || WizardMode) {
3840 for (int i = 0; i < array->length(); i++) {
3841 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3842 }
3843 }
3844 }
3845
3846 static void print_array_on(outputStream* st, Array<int>* array) {
3847 if (array == nullptr) { st->print_cr("nullptr"); return; }
3848 array->print_value_on(st); st->cr();
3849 if (Verbose || WizardMode) {
3850 for (int i = 0; i < array->length(); i++) {
3851 st->print("%d : %d", i, array->at(i)); st->cr();
3852 }
3853 }
3854 }
3855
3856 const char* InstanceKlass::init_state_name() const {
3857 return state_names[init_state()];
3858 }
3859
3860 void InstanceKlass::print_on(outputStream* st) const {
3861 assert(is_klass(), "must be klass");
3862 Klass::print_on(st);
3863
3864 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3865 st->print(BULLET"klass size: %d", size()); st->cr();
3866 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3867 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3868 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3869 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3870 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3871 st->print(BULLET"sub: ");
3872 Klass* sub = subklass();
3873 int n;
3874 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3875 if (n < MaxSubklassPrintSize) {
3876 sub->print_value_on(st);
3877 st->print(" ");
3878 }
3879 }
3880 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3881 st->cr();
3882
3883 if (is_interface()) {
3884 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3885 if (nof_implementors() == 1) {
3886 st->print_cr(BULLET"implementor: ");
3887 st->print(" ");
3888 implementor()->print_value_on(st);
3889 st->cr();
3890 }
3891 }
3892
3893 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3894 st->print(BULLET"methods: "); print_array_on(st, methods());
3895 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3896 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3897 if (default_vtable_indices() != nullptr) {
3898 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3899 }
3900 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3901 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3902 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3903 if (class_loader_data() != nullptr) {
3904 st->print(BULLET"class loader data: ");
3905 class_loader_data()->print_value_on(st);
3906 st->cr();
3907 }
3908 if (source_file_name() != nullptr) {
3909 st->print(BULLET"source file: ");
3910 source_file_name()->print_value_on(st);
3911 st->cr();
3912 }
3913 if (source_debug_extension() != nullptr) {
3914 st->print(BULLET"source debug extension: ");
3915 st->print("%s", source_debug_extension());
3916 st->cr();
3917 }
3918 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3919 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3920 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3921 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3922 {
3923 bool have_pv = false;
3924 // previous versions are linked together through the InstanceKlass
3925 for (InstanceKlass* pv_node = previous_versions();
3926 pv_node != nullptr;
3927 pv_node = pv_node->previous_versions()) {
3928 if (!have_pv)
3929 st->print(BULLET"previous version: ");
3930 have_pv = true;
3931 pv_node->constants()->print_value_on(st);
3932 }
3933 if (have_pv) st->cr();
3934 }
3935
3936 if (generic_signature() != nullptr) {
3937 st->print(BULLET"generic signature: ");
3938 generic_signature()->print_value_on(st);
3939 st->cr();
3940 }
3941 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3942 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3943 if (record_components() != nullptr) {
3944 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3945 }
3946 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3947 st->print(BULLET"preload classes: "); preload_classes()->print_value_on(st); st->cr();
3948 if (java_mirror() != nullptr) {
3949 st->print(BULLET"java mirror: ");
3950 java_mirror()->print_value_on(st);
3951 st->cr();
3952 } else {
3953 st->print_cr(BULLET"java mirror: null");
3954 }
3955 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3956 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3957 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3958 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3959 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3960 FieldPrinter print_static_field(st);
3961 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3962 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3963 FieldPrinter print_nonstatic_field(st);
3964 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3965 ik->print_nonstatic_fields(&print_nonstatic_field);
3966
3967 st->print(BULLET"non-static oop maps: ");
3968 OopMapBlock* map = start_of_nonstatic_oop_maps();
3969 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3970 while (map < end_map) {
3971 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3972 map++;
3973 }
3974 st->cr();
3975 }
3976
3977 void InstanceKlass::print_value_on(outputStream* st) const {
3978 assert(is_klass(), "must be klass");
3979 if (Verbose || WizardMode) access_flags().print_on(st);
3980 name()->print_value_on(st);
3981 }
3982
3983 void FieldPrinter::do_field(fieldDescriptor* fd) {
3984 _st->print(BULLET);
3985 if (_obj == nullptr) {
3986 fd->print_on(_st);
3987 _st->cr();
3988 } else {
3989 fd->print_on_for(_st, _obj);
3990 _st->cr();
3991 }
3992 }
3993
3994
3995 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3996 Klass::oop_print_on(obj, st);
3997
3998 if (this == vmClasses::String_klass()) {
3999 typeArrayOop value = java_lang_String::value(obj);
4000 juint length = java_lang_String::length(obj);
4001 if (value != nullptr &&
4002 value->is_typeArray() &&
4003 length <= (juint) value->length()) {
4004 st->print(BULLET"string: ");
4005 java_lang_String::print(obj, st);
4006 st->cr();
4007 }
4008 }
4009
4010 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
4011 FieldPrinter print_field(st, obj);
4012 print_nonstatic_fields(&print_field);
4013
4014 if (this == vmClasses::Class_klass()) {
4015 st->print(BULLET"signature: ");
4016 java_lang_Class::print_signature(obj, st);
4017 st->cr();
4018 Klass* real_klass = java_lang_Class::as_Klass(obj);
4019 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4020 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4021 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4022 }
4023 } else if (this == vmClasses::MethodType_klass()) {
4024 st->print(BULLET"signature: ");
4025 java_lang_invoke_MethodType::print_signature(obj, st);
4026 st->cr();
4027 }
4028 }
4029
4030 #ifndef PRODUCT
4031
4032 bool InstanceKlass::verify_itable_index(int i) {
4033 int method_count = klassItable::method_count_for_interface(this);
4034 assert(i >= 0 && i < method_count, "index out of bounds");
4035 return true;
4036 }
4037
4038 #endif //PRODUCT
4039
4040 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4041 st->print("a ");
4042 name()->print_value_on(st);
4043 obj->print_address_on(st);
4044 if (this == vmClasses::String_klass()
4045 && java_lang_String::value(obj) != nullptr) {
4046 ResourceMark rm;
4047 int len = java_lang_String::length(obj);
4048 int plen = (len < 24 ? len : 12);
4049 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4050 st->print(" = \"%s\"", str);
4051 if (len > plen)
4052 st->print("...[%d]", len);
4053 } else if (this == vmClasses::Class_klass()) {
4054 Klass* k = java_lang_Class::as_Klass(obj);
4055 st->print(" = ");
4056 if (k != nullptr) {
4057 k->print_value_on(st);
4058 } else {
4059 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4060 st->print("%s", tname ? tname : "type?");
4061 }
4062 } else if (this == vmClasses::MethodType_klass()) {
4063 st->print(" = ");
4064 java_lang_invoke_MethodType::print_signature(obj, st);
4065 } else if (java_lang_boxing_object::is_instance(obj)) {
4066 st->print(" = ");
4067 java_lang_boxing_object::print(obj, st);
4068 } else if (this == vmClasses::LambdaForm_klass()) {
4069 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4070 if (vmentry != nullptr) {
4071 st->print(" => ");
4072 vmentry->print_value_on(st);
4073 }
4074 } else if (this == vmClasses::MemberName_klass()) {
4075 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4076 if (vmtarget != nullptr) {
4077 st->print(" = ");
4078 vmtarget->print_value_on(st);
4079 } else {
4080 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4081 oop name = java_lang_invoke_MemberName::name(obj);
4082 if (clazz != nullptr) {
4083 clazz->print_value_on(st);
4084 } else {
4085 st->print("null");
4086 }
4087 st->print(".");
4088 if (name != nullptr) {
4089 name->print_value_on(st);
4090 } else {
4091 st->print("null");
4092 }
4093 }
4094 }
4095 }
4096
4097 const char* InstanceKlass::internal_name() const {
4098 return external_name();
4099 }
4100
4101 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4102 const ModuleEntry* module_entry,
4103 const ClassFileStream* cfs) const {
4104
4105 if (ClassListWriter::is_enabled()) {
4106 ClassListWriter::write(this, cfs);
4107 }
4108
4109 print_class_load_helper(loader_data, module_entry, cfs);
4110 print_class_load_cause_logging();
4111 }
4112
4113 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4114 const ModuleEntry* module_entry,
4115 const ClassFileStream* cfs) const {
4116
4117 if (!log_is_enabled(Info, class, load)) {
4118 return;
4119 }
4120
4121 ResourceMark rm;
4122 LogMessage(class, load) msg;
4123 stringStream info_stream;
4124
4125 // Name and class hierarchy info
4126 info_stream.print("%s", external_name());
4127
4128 // Source
4129 if (cfs != nullptr) {
4130 if (cfs->source() != nullptr) {
4131 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4132 if (module_name != nullptr) {
4133 // When the boot loader created the stream, it didn't know the module name
4134 // yet. Let's format it now.
4135 if (cfs->from_boot_loader_modules_image()) {
4136 info_stream.print(" source: jrt:/%s", module_name);
4137 } else {
4138 info_stream.print(" source: %s", cfs->source());
4139 }
4140 } else {
4141 info_stream.print(" source: %s", cfs->source());
4142 }
4143 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4144 Thread* current = Thread::current();
4145 Klass* caller = current->is_Java_thread() ?
4146 JavaThread::cast(current)->security_get_caller_class(1):
4147 nullptr;
4148 // caller can be null, for example, during a JVMTI VM_Init hook
4149 if (caller != nullptr) {
4150 info_stream.print(" source: instance of %s", caller->external_name());
4151 } else {
4152 // source is unknown
4153 }
4154 } else {
4155 oop class_loader = loader_data->class_loader();
4156 info_stream.print(" source: %s", class_loader->klass()->external_name());
4157 }
4158 } else {
4159 assert(this->is_shared(), "must be");
4160 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4161 info_stream.print(" source: shared objects file (top)");
4162 } else {
4163 info_stream.print(" source: shared objects file");
4164 }
4165 }
4166
4167 msg.info("%s", info_stream.as_string());
4168
4169 if (log_is_enabled(Debug, class, load)) {
4170 stringStream debug_stream;
4171
4172 // Class hierarchy info
4173 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4174 p2i(this), p2i(superklass()));
4175
4176 // Interfaces
4177 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4178 debug_stream.print(" interfaces:");
4179 int length = local_interfaces()->length();
4180 for (int i = 0; i < length; i++) {
4181 debug_stream.print(" " PTR_FORMAT,
4182 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4183 }
4184 }
4185
4186 // Class loader
4187 debug_stream.print(" loader: [");
4188 loader_data->print_value_on(&debug_stream);
4189 debug_stream.print("]");
4190
4191 // Classfile checksum
4192 if (cfs) {
4193 debug_stream.print(" bytes: %d checksum: %08x",
4194 cfs->length(),
4195 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4196 cfs->length()));
4197 }
4198
4199 msg.debug("%s", debug_stream.as_string());
4200 }
4201 }
4202
4203 void InstanceKlass::print_class_load_cause_logging() const {
4204 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4205 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4206 JavaThread* current = JavaThread::current();
4207 ResourceMark rm(current);
4208 const char* name = external_name();
4209
4210 if (LogClassLoadingCauseFor == nullptr ||
4211 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4212 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4213 return;
4214 }
4215
4216 // Log Java stack first
4217 {
4218 LogMessage(class, load, cause) msg;
4219 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4220
4221 info_stream.print_cr("Java stack when loading %s:", name);
4222 current->print_stack_on(&info_stream);
4223 }
4224
4225 // Log native stack second
4226 if (log_cause_native) {
4227 // Log to string first so that lines can be indented
4228 stringStream stack_stream;
4229 char buf[O_BUFLEN];
4230 address lastpc = nullptr;
4231 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4232 // We have printed the native stack in platform-specific code,
4233 // so nothing else to do in this case.
4234 } else {
4235 frame f = os::current_frame();
4236 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4237 -1 /* max stack_stream */, buf, O_BUFLEN);
4238 }
4239
4240 LogMessage(class, load, cause, native) msg;
4241 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4242 info_stream.print_cr("Native stack when loading %s:", name);
4243
4244 // Print each native stack line to the log
4245 int size = (int) stack_stream.size();
4246 char* stack = stack_stream.as_string();
4247 char* stack_end = stack + size;
4248 char* line_start = stack;
4249 for (char* p = stack; p < stack_end; p++) {
4250 if (*p == '\n') {
4251 *p = '\0';
4252 info_stream.print_cr("\t%s", line_start);
4253 line_start = p + 1;
4254 }
4255 }
4256 if (line_start < stack_end) {
4257 info_stream.print_cr("\t%s", line_start);
4258 }
4259 }
4260 }
4261 }
4262
4263 // Verification
4264
4265 class VerifyFieldClosure: public BasicOopIterateClosure {
4266 protected:
4267 template <class T> void do_oop_work(T* p) {
4268 oop obj = RawAccess<>::oop_load(p);
4269 if (!oopDesc::is_oop_or_null(obj)) {
4270 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4271 Universe::print_on(tty);
4272 guarantee(false, "boom");
4273 }
4274 }
4275 public:
4276 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4277 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4278 };
4279
4280 void InstanceKlass::verify_on(outputStream* st) {
4281 #ifndef PRODUCT
4282 // Avoid redundant verifies, this really should be in product.
4283 if (_verify_count == Universe::verify_count()) return;
4284 _verify_count = Universe::verify_count();
4285 #endif
4286
4287 // Verify Klass
4288 Klass::verify_on(st);
4289
4290 // Verify that klass is present in ClassLoaderData
4291 guarantee(class_loader_data()->contains_klass(this),
4292 "this class isn't found in class loader data");
4293
4294 // Verify vtables
4295 if (is_linked()) {
4296 // $$$ This used to be done only for m/s collections. Doing it
4297 // always seemed a valid generalization. (DLD -- 6/00)
4298 vtable().verify(st);
4299 }
4300
4301 // Verify first subklass
4302 if (subklass() != nullptr) {
4303 guarantee(subklass()->is_klass(), "should be klass");
4304 }
4305
4306 // Verify siblings
4307 Klass* super = this->super();
4308 Klass* sib = next_sibling();
4309 if (sib != nullptr) {
4310 if (sib == this) {
4311 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4312 }
4313
4314 guarantee(sib->is_klass(), "should be klass");
4315 guarantee(sib->super() == super, "siblings should have same superklass");
4316 }
4317
4318 // Verify local interfaces
4319 if (local_interfaces()) {
4320 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4321 for (int j = 0; j < local_interfaces->length(); j++) {
4322 InstanceKlass* e = local_interfaces->at(j);
4323 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4324 }
4325 }
4326
4327 // Verify transitive interfaces
4328 if (transitive_interfaces() != nullptr) {
4329 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4330 for (int j = 0; j < transitive_interfaces->length(); j++) {
4331 InstanceKlass* e = transitive_interfaces->at(j);
4332 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4333 }
4334 }
4335
4336 // Verify methods
4337 if (methods() != nullptr) {
4338 Array<Method*>* methods = this->methods();
4339 for (int j = 0; j < methods->length(); j++) {
4340 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4341 }
4342 for (int j = 0; j < methods->length() - 1; j++) {
4343 Method* m1 = methods->at(j);
4344 Method* m2 = methods->at(j + 1);
4345 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4346 }
4347 }
4348
4349 // Verify method ordering
4350 if (method_ordering() != nullptr) {
4351 Array<int>* method_ordering = this->method_ordering();
4352 int length = method_ordering->length();
4353 if (JvmtiExport::can_maintain_original_method_order() ||
4354 ((UseSharedSpaces || CDSConfig::is_dumping_archive()) && length != 0)) {
4355 guarantee(length == methods()->length(), "invalid method ordering length");
4356 jlong sum = 0;
4357 for (int j = 0; j < length; j++) {
4358 int original_index = method_ordering->at(j);
4359 guarantee(original_index >= 0, "invalid method ordering index");
4360 guarantee(original_index < length, "invalid method ordering index");
4361 sum += original_index;
4362 }
4363 // Verify sum of indices 0,1,...,length-1
4364 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4365 } else {
4366 guarantee(length == 0, "invalid method ordering length");
4367 }
4368 }
4369
4370 // Verify default methods
4371 if (default_methods() != nullptr) {
4372 Array<Method*>* methods = this->default_methods();
4373 for (int j = 0; j < methods->length(); j++) {
4374 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4375 }
4376 for (int j = 0; j < methods->length() - 1; j++) {
4377 Method* m1 = methods->at(j);
4378 Method* m2 = methods->at(j + 1);
4379 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4380 }
4381 }
4382
4383 // Verify JNI static field identifiers
4384 if (jni_ids() != nullptr) {
4385 jni_ids()->verify(this);
4386 }
4387
4388 // Verify other fields
4389 if (constants() != nullptr) {
4390 guarantee(constants()->is_constantPool(), "should be constant pool");
4391 }
4392 }
4393
4394 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4395 Klass::oop_verify_on(obj, st);
4396 VerifyFieldClosure blk;
4397 obj->oop_iterate(&blk);
4398 }
4399
4400
4401 // JNIid class for jfieldIDs only
4402 // Note to reviewers:
4403 // These JNI functions are just moved over to column 1 and not changed
4404 // in the compressed oops workspace.
4405 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4406 _holder = holder;
4407 _offset = offset;
4408 _next = next;
4409 debug_only(_is_static_field_id = false;)
4410 }
4411
4412
4413 JNIid* JNIid::find(int offset) {
4414 JNIid* current = this;
4415 while (current != nullptr) {
4416 if (current->offset() == offset) return current;
4417 current = current->next();
4418 }
4419 return nullptr;
4420 }
4421
4422 void JNIid::deallocate(JNIid* current) {
4423 while (current != nullptr) {
4424 JNIid* next = current->next();
4425 delete current;
4426 current = next;
4427 }
4428 }
4429
4430
4431 void JNIid::verify(Klass* holder) {
4432 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4433 int end_field_offset;
4434 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4435
4436 JNIid* current = this;
4437 while (current != nullptr) {
4438 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4439 #ifdef ASSERT
4440 int o = current->offset();
4441 if (current->is_static_field_id()) {
4442 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4443 }
4444 #endif
4445 current = current->next();
4446 }
4447 }
4448
4449 void InstanceKlass::set_init_state(ClassState state) {
4450 if (state > loaded) {
4451 assert_lock_strong(_init_monitor);
4452 }
4453 #ifdef ASSERT
4454 bool good_state = is_shared() ? (_init_state <= state)
4455 : (_init_state < state);
4456 bool link_failed = _init_state == being_linked && state == loaded;
4457 assert(good_state || state == allocated || link_failed, "illegal state transition");
4458 #endif
4459 assert(_init_thread == nullptr, "should be cleared before state change");
4460 Atomic::store(&_init_state, state);
4461 }
4462
4463 #if INCLUDE_JVMTI
4464
4465 // RedefineClasses() support for previous versions
4466
4467 // Globally, there is at least one previous version of a class to walk
4468 // during class unloading, which is saved because old methods in the class
4469 // are still running. Otherwise the previous version list is cleaned up.
4470 bool InstanceKlass::_should_clean_previous_versions = false;
4471
4472 // Returns true if there are previous versions of a class for class
4473 // unloading only. Also resets the flag to false. purge_previous_version
4474 // will set the flag to true if there are any left, i.e., if there's any
4475 // work to do for next time. This is to avoid the expensive code cache
4476 // walk in CLDG::clean_deallocate_lists().
4477 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4478 bool ret = _should_clean_previous_versions;
4479 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4480 ret ? "true" : "false");
4481 _should_clean_previous_versions = false;
4482 return ret;
4483 }
4484
4485 // This nulls out jmethodIDs for all methods in 'klass'
4486 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4487 // during class unloading.
4488 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4489 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4490 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4491 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4492 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4493 Array<Method*>* method_refs = klass->methods();
4494 for (int k = 0; k < method_refs->length(); k++) {
4495 Method* method = method_refs->at(k);
4496 if (method != nullptr && method->is_obsolete()) {
4497 method->clear_jmethod_id();
4498 }
4499 }
4500 }
4501
4502 // Purge previous versions before adding new previous versions of the class and
4503 // during class unloading.
4504 void InstanceKlass::purge_previous_version_list() {
4505 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4506 assert(has_been_redefined(), "Should only be called for main class");
4507
4508 // Quick exit.
4509 if (previous_versions() == nullptr) {
4510 return;
4511 }
4512
4513 // This klass has previous versions so see what we can cleanup
4514 // while it is safe to do so.
4515
4516 int deleted_count = 0; // leave debugging breadcrumbs
4517 int live_count = 0;
4518 ClassLoaderData* loader_data = class_loader_data();
4519 assert(loader_data != nullptr, "should never be null");
4520
4521 ResourceMark rm;
4522 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4523
4524 // previous versions are linked together through the InstanceKlass
4525 InstanceKlass* pv_node = previous_versions();
4526 InstanceKlass* last = this;
4527 int version = 0;
4528
4529 // check the previous versions list
4530 for (; pv_node != nullptr; ) {
4531
4532 ConstantPool* pvcp = pv_node->constants();
4533 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4534
4535 if (!pvcp->on_stack()) {
4536 // If the constant pool isn't on stack, none of the methods
4537 // are executing. Unlink this previous_version.
4538 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4539 // so will be deallocated during the next phase of class unloading.
4540 log_trace(redefine, class, iklass, purge)
4541 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4542 // Unlink from previous version list.
4543 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4544 InstanceKlass* next = pv_node->previous_versions();
4545 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4546 pv_node->link_previous_versions(nullptr); // point next to null
4547 last->link_previous_versions(next);
4548 // Delete this node directly. Nothing is referring to it and we don't
4549 // want it to increase the counter for metadata to delete in CLDG.
4550 MetadataFactory::free_metadata(loader_data, pv_node);
4551 pv_node = next;
4552 deleted_count++;
4553 version++;
4554 continue;
4555 } else {
4556 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4557 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4558 live_count++;
4559 if (pvcp->is_shared()) {
4560 // Shared previous versions can never be removed so no cleaning is needed.
4561 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4562 } else {
4563 // Previous version alive, set that clean is needed for next time.
4564 _should_clean_previous_versions = true;
4565 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4566 }
4567 }
4568
4569 // next previous version
4570 last = pv_node;
4571 pv_node = pv_node->previous_versions();
4572 version++;
4573 }
4574 log_trace(redefine, class, iklass, purge)
4575 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4576 }
4577
4578 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4579 int emcp_method_count) {
4580 int obsolete_method_count = old_methods->length() - emcp_method_count;
4581
4582 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4583 _previous_versions != nullptr) {
4584 // We have a mix of obsolete and EMCP methods so we have to
4585 // clear out any matching EMCP method entries the hard way.
4586 int local_count = 0;
4587 for (int i = 0; i < old_methods->length(); i++) {
4588 Method* old_method = old_methods->at(i);
4589 if (old_method->is_obsolete()) {
4590 // only obsolete methods are interesting
4591 Symbol* m_name = old_method->name();
4592 Symbol* m_signature = old_method->signature();
4593
4594 // previous versions are linked together through the InstanceKlass
4595 int j = 0;
4596 for (InstanceKlass* prev_version = _previous_versions;
4597 prev_version != nullptr;
4598 prev_version = prev_version->previous_versions(), j++) {
4599
4600 Array<Method*>* method_refs = prev_version->methods();
4601 for (int k = 0; k < method_refs->length(); k++) {
4602 Method* method = method_refs->at(k);
4603
4604 if (!method->is_obsolete() &&
4605 method->name() == m_name &&
4606 method->signature() == m_signature) {
4607 // The current RedefineClasses() call has made all EMCP
4608 // versions of this method obsolete so mark it as obsolete
4609 log_trace(redefine, class, iklass, add)
4610 ("%s(%s): flush obsolete method @%d in version @%d",
4611 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4612
4613 method->set_is_obsolete();
4614 break;
4615 }
4616 }
4617
4618 // The previous loop may not find a matching EMCP method, but
4619 // that doesn't mean that we can optimize and not go any
4620 // further back in the PreviousVersion generations. The EMCP
4621 // method for this generation could have already been made obsolete,
4622 // but there still may be an older EMCP method that has not
4623 // been made obsolete.
4624 }
4625
4626 if (++local_count >= obsolete_method_count) {
4627 // no more obsolete methods so bail out now
4628 break;
4629 }
4630 }
4631 }
4632 }
4633 }
4634
4635 // Save the scratch_class as the previous version if any of the methods are running.
4636 // The previous_versions are used to set breakpoints in EMCP methods and they are
4637 // also used to clean MethodData links to redefined methods that are no longer running.
4638 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4639 int emcp_method_count) {
4640 assert(Thread::current()->is_VM_thread(),
4641 "only VMThread can add previous versions");
4642
4643 ResourceMark rm;
4644 log_trace(redefine, class, iklass, add)
4645 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4646
4647 // Clean out old previous versions for this class
4648 purge_previous_version_list();
4649
4650 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4651 // a previous redefinition may be made obsolete by this redefinition.
4652 Array<Method*>* old_methods = scratch_class->methods();
4653 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4654
4655 // If the constant pool for this previous version of the class
4656 // is not marked as being on the stack, then none of the methods
4657 // in this previous version of the class are on the stack so
4658 // we don't need to add this as a previous version.
4659 ConstantPool* cp_ref = scratch_class->constants();
4660 if (!cp_ref->on_stack()) {
4661 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4662 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4663 return;
4664 }
4665
4666 // Add previous version if any methods are still running or if this is
4667 // a shared class which should never be removed.
4668 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4669 scratch_class->link_previous_versions(previous_versions());
4670 link_previous_versions(scratch_class);
4671 if (cp_ref->is_shared()) {
4672 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4673 } else {
4674 // We only set clean_previous_versions flag for processing during class
4675 // unloading for non-shared classes.
4676 _should_clean_previous_versions = true;
4677 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4678 }
4679 } // end add_previous_version()
4680
4681 #endif // INCLUDE_JVMTI
4682
4683 Method* InstanceKlass::method_with_idnum(int idnum) {
4684 Method* m = nullptr;
4685 if (idnum < methods()->length()) {
4686 m = methods()->at(idnum);
4687 }
4688 if (m == nullptr || m->method_idnum() != idnum) {
4689 for (int index = 0; index < methods()->length(); ++index) {
4690 m = methods()->at(index);
4691 if (m->method_idnum() == idnum) {
4692 return m;
4693 }
4694 }
4695 // None found, return null for the caller to handle.
4696 return nullptr;
4697 }
4698 return m;
4699 }
4700
4701
4702 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4703 if (idnum >= methods()->length()) {
4704 return nullptr;
4705 }
4706 Method* m = methods()->at(idnum);
4707 if (m != nullptr && m->orig_method_idnum() == idnum) {
4708 return m;
4709 }
4710 // Obsolete method idnum does not match the original idnum
4711 for (int index = 0; index < methods()->length(); ++index) {
4712 m = methods()->at(index);
4713 if (m->orig_method_idnum() == idnum) {
4714 return m;
4715 }
4716 }
4717 // None found, return null for the caller to handle.
4718 return nullptr;
4719 }
4720
4721
4722 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4723 InstanceKlass* holder = get_klass_version(version);
4724 if (holder == nullptr) {
4725 return nullptr; // The version of klass is gone, no method is found
4726 }
4727 Method* method = holder->method_with_orig_idnum(idnum);
4728 return method;
4729 }
4730
4731 #if INCLUDE_JVMTI
4732 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4733 return _cached_class_file;
4734 }
4735
4736 jint InstanceKlass::get_cached_class_file_len() {
4737 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4738 }
4739
4740 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4741 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4742 }
4743 #endif
4744
4745 // Make a step iterating over the class hierarchy under the root class.
4746 // Skips subclasses if requested.
4747 void ClassHierarchyIterator::next() {
4748 assert(_current != nullptr, "required");
4749 if (_visit_subclasses && _current->subklass() != nullptr) {
4750 _current = _current->subklass();
4751 return; // visit next subclass
4752 }
4753 _visit_subclasses = true; // reset
4754 while (_current->next_sibling() == nullptr && _current != _root) {
4755 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4756 }
4757 if (_current == _root) {
4758 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4759 _current = nullptr;
4760 return;
4761 }
4762 _current = _current->next_sibling();
4763 return; // visit next sibling subclass
4764 }