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/reflection.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_loadable_descriptors_attribute(Symbol* name) const {
176 if (_loadable_descriptors == nullptr) return false;
177 for (int i = 0; i < _loadable_descriptors->length(); i++) {
178 Symbol* class_name = _constants->klass_at_noresolve(_loadable_descriptors->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 _null_marker_offsets(nullptr),
571 _loadable_descriptors(nullptr),
572 _adr_inlineklass_fixed_block(nullptr)
573 {
574 set_vtable_length(parser.vtable_size());
575 set_access_flags(parser.access_flags());
576 if (parser.is_hidden()) set_is_hidden();
577 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
578 false));
579 if (parser.has_inline_fields()) {
580 set_has_inline_type_fields();
581 }
582
583 assert(nullptr == _methods, "underlying memory not zeroed?");
584 assert(is_instance_klass(), "is layout incorrect?");
585 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
586 }
587
588 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
589 Array<Method*>* methods) {
590 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
591 !methods->is_shared()) {
592 for (int i = 0; i < methods->length(); i++) {
593 Method* method = methods->at(i);
594 if (method == nullptr) continue; // maybe null if error processing
595 // Only want to delete methods that are not executing for RedefineClasses.
596 // The previous version will point to them so they're not totally dangling
597 assert (!method->on_stack(), "shouldn't be called with methods on stack");
598 MetadataFactory::free_metadata(loader_data, method);
599 }
600 MetadataFactory::free_array<Method*>(loader_data, methods);
601 }
602 }
603
604 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
605 const Klass* super_klass,
606 Array<InstanceKlass*>* local_interfaces,
607 Array<InstanceKlass*>* transitive_interfaces) {
608 // Only deallocate transitive interfaces if not empty, same as super class
609 // or same as local interfaces. See code in parseClassFile.
610 Array<InstanceKlass*>* ti = transitive_interfaces;
611 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
612 // check that the interfaces don't come from super class
613 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
614 InstanceKlass::cast(super_klass)->transitive_interfaces();
615 if (ti != sti && ti != nullptr && !ti->is_shared()) {
616 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
617 }
618 }
619
620 // local interfaces can be empty
621 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
622 local_interfaces != nullptr && !local_interfaces->is_shared()) {
623 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
624 }
625 }
626
627 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
628 Array<RecordComponent*>* record_components) {
629 if (record_components != nullptr && !record_components->is_shared()) {
630 for (int i = 0; i < record_components->length(); i++) {
631 RecordComponent* record_component = record_components->at(i);
632 MetadataFactory::free_metadata(loader_data, record_component);
633 }
634 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
635 }
636 }
637
638 // This function deallocates the metadata and C heap pointers that the
639 // InstanceKlass points to.
640 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
641 // Orphan the mirror first, CMS thinks it's still live.
642 if (java_mirror() != nullptr) {
643 java_lang_Class::set_klass(java_mirror(), nullptr);
644 }
645
646 // Also remove mirror from handles
647 loader_data->remove_handle(_java_mirror);
648
649 // Need to take this class off the class loader data list.
650 loader_data->remove_class(this);
651
652 // The array_klass for this class is created later, after error handling.
653 // For class redefinition, we keep the original class so this scratch class
654 // doesn't have an array class. Either way, assert that there is nothing
655 // to deallocate.
656 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
657
658 // Release C heap allocated data that this points to, which includes
659 // reference counting symbol names.
660 // Can't release the constant pool or MethodData C heap data here because the constant
661 // pool can be deallocated separately from the InstanceKlass for default methods and
662 // redefine classes. MethodData can also be released separately.
663 release_C_heap_structures(/* release_sub_metadata */ false);
664
665 deallocate_methods(loader_data, methods());
666 set_methods(nullptr);
667
668 deallocate_record_components(loader_data, record_components());
669 set_record_components(nullptr);
670
671 if (method_ordering() != nullptr &&
672 method_ordering() != Universe::the_empty_int_array() &&
673 !method_ordering()->is_shared()) {
674 MetadataFactory::free_array<int>(loader_data, method_ordering());
675 }
676 set_method_ordering(nullptr);
677
678 // default methods can be empty
679 if (default_methods() != nullptr &&
680 default_methods() != Universe::the_empty_method_array() &&
681 !default_methods()->is_shared()) {
682 MetadataFactory::free_array<Method*>(loader_data, default_methods());
683 }
684 // Do NOT deallocate the default methods, they are owned by superinterfaces.
685 set_default_methods(nullptr);
686
687 // default methods vtable indices can be empty
688 if (default_vtable_indices() != nullptr &&
689 !default_vtable_indices()->is_shared()) {
690 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
691 }
692 set_default_vtable_indices(nullptr);
693
694
695 // This array is in Klass, but remove it with the InstanceKlass since
696 // this place would be the only caller and it can share memory with transitive
697 // interfaces.
698 if (secondary_supers() != nullptr &&
699 secondary_supers() != Universe::the_empty_klass_array() &&
700 // see comments in compute_secondary_supers about the following cast
701 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
702 !secondary_supers()->is_shared()) {
703 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
704 }
705 set_secondary_supers(nullptr);
706
707 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
708 set_transitive_interfaces(nullptr);
709 set_local_interfaces(nullptr);
710
711 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
712 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
713 }
714 set_fieldinfo_stream(nullptr);
715
716 if (fields_status() != nullptr && !fields_status()->is_shared()) {
717 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
718 }
719 set_fields_status(nullptr);
720
721 if (inline_type_field_klasses_array() != nullptr) {
722 MetadataFactory::free_array<InlineKlass*>(loader_data, inline_type_field_klasses_array());
723 set_inline_type_field_klasses_array(nullptr);
724 }
725
726 if (null_marker_offsets_array() != nullptr) {
727 MetadataFactory::free_array<int>(loader_data, null_marker_offsets_array());
728 set_null_marker_offsets_array(nullptr);
729 }
730
731 // If a method from a redefined class is using this constant pool, don't
732 // delete it, yet. The new class's previous version will point to this.
733 if (constants() != nullptr) {
734 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
735 if (!constants()->is_shared()) {
736 MetadataFactory::free_metadata(loader_data, constants());
737 }
738 // Delete any cached resolution errors for the constant pool
739 SystemDictionary::delete_resolution_error(constants());
740
741 set_constants(nullptr);
742 }
743
744 if (inner_classes() != nullptr &&
745 inner_classes() != Universe::the_empty_short_array() &&
746 !inner_classes()->is_shared()) {
747 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
748 }
749 set_inner_classes(nullptr);
750
751 if (nest_members() != nullptr &&
752 nest_members() != Universe::the_empty_short_array() &&
753 !nest_members()->is_shared()) {
754 MetadataFactory::free_array<jushort>(loader_data, nest_members());
755 }
756 set_nest_members(nullptr);
757
758 if (permitted_subclasses() != nullptr &&
759 permitted_subclasses() != Universe::the_empty_short_array() &&
760 !permitted_subclasses()->is_shared()) {
761 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
762 }
763 set_permitted_subclasses(nullptr);
764
765 if (loadable_descriptors() != nullptr &&
766 loadable_descriptors() != Universe::the_empty_short_array() &&
767 !loadable_descriptors()->is_shared()) {
768 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
769 }
770 set_loadable_descriptors(nullptr);
771
772 // We should deallocate the Annotations instance if it's not in shared spaces.
773 if (annotations() != nullptr && !annotations()->is_shared()) {
774 MetadataFactory::free_metadata(loader_data, annotations());
775 }
776 set_annotations(nullptr);
777
778 SystemDictionaryShared::handle_class_unloading(this);
779
780 #if INCLUDE_CDS_JAVA_HEAP
781 if (CDSConfig::is_dumping_heap()) {
782 HeapShared::remove_scratch_objects(this);
783 }
784 #endif
785 }
786
787 bool InstanceKlass::is_record() const {
788 return _record_components != nullptr &&
789 is_final() &&
790 java_super() == vmClasses::Record_klass();
791 }
792
793 bool InstanceKlass::is_sealed() const {
794 return _permitted_subclasses != nullptr &&
795 _permitted_subclasses != Universe::the_empty_short_array();
796 }
797
798 bool InstanceKlass::should_be_initialized() const {
799 return !is_initialized();
800 }
801
802 klassItable InstanceKlass::itable() const {
803 return klassItable(const_cast<InstanceKlass*>(this));
804 }
805
806 // JVMTI spec thinks there are signers and protection domain in the
807 // instanceKlass. These accessors pretend these fields are there.
808 // The hprof specification also thinks these fields are in InstanceKlass.
809 oop InstanceKlass::protection_domain() const {
810 // return the protection_domain from the mirror
811 return java_lang_Class::protection_domain(java_mirror());
812 }
813
814 objArrayOop InstanceKlass::signers() const {
815 // return the signers from the mirror
816 return java_lang_Class::signers(java_mirror());
817 }
818
819 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
820 // process. The step comments refers to the procedure described in that section.
821 // Note: implementation moved to static method to expose the this pointer.
822 void InstanceKlass::initialize(TRAPS) {
823 if (this->should_be_initialized()) {
824 initialize_impl(CHECK);
825 // Note: at this point the class may be initialized
826 // OR it may be in the state of being initialized
827 // in case of recursive initialization!
828 } else {
829 assert(is_initialized(), "sanity check");
830 }
831 }
832
833
834 bool InstanceKlass::verify_code(TRAPS) {
835 // 1) Verify the bytecodes
836 return Verifier::verify(this, should_verify_class(), THREAD);
837 }
838
839 void InstanceKlass::link_class(TRAPS) {
840 assert(is_loaded(), "must be loaded");
841 if (!is_linked()) {
842 link_class_impl(CHECK);
843 }
844 }
845
846 void InstanceKlass::check_link_state_and_wait(JavaThread* current) {
847 MonitorLocker ml(current, _init_monitor);
848
849 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
850
851 // Another thread is linking this class, wait.
852 while (is_being_linked() && !is_init_thread(current)) {
853 if (debug_logging_enabled) {
854 ResourceMark rm(current);
855 log_debug(class, init)("Thread \"%s\" waiting for linking of %s by thread \"%s\"",
856 current->name(), external_name(), init_thread_name());
857 }
858 ml.wait();
859 }
860
861 // This thread is recursively linking this class, continue
862 if (is_being_linked() && is_init_thread(current)) {
863 if (debug_logging_enabled) {
864 ResourceMark rm(current);
865 log_debug(class, init)("Thread \"%s\" recursively linking %s",
866 current->name(), external_name());
867 }
868 return;
869 }
870
871 // If this class wasn't linked already, set state to being_linked
872 if (!is_linked()) {
873 if (debug_logging_enabled) {
874 ResourceMark rm(current);
875 log_debug(class, init)("Thread \"%s\" linking %s",
876 current->name(), external_name());
877 }
878 set_init_state(being_linked);
879 set_init_thread(current);
880 } else {
881 if (debug_logging_enabled) {
882 ResourceMark rm(current);
883 log_debug(class, init)("Thread \"%s\" found %s already linked",
884 current->name(), external_name());
885 }
886 }
887 }
888
889 // Called to verify that a class can link during initialization, without
890 // throwing a VerifyError.
891 bool InstanceKlass::link_class_or_fail(TRAPS) {
892 assert(is_loaded(), "must be loaded");
893 if (!is_linked()) {
894 link_class_impl(CHECK_false);
895 }
896 return is_linked();
897 }
898
899 bool InstanceKlass::link_class_impl(TRAPS) {
900 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
901 // This is for CDS static dump only -- we use the in_error_state to indicate that
902 // the class has failed verification. Throwing the NoClassDefFoundError here is just
903 // a convenient way to stop repeat attempts to verify the same (bad) class.
904 //
905 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
906 // if we are executing Java code. This is not a problem for CDS dumping phase since
907 // it doesn't execute any Java code.
908 ResourceMark rm(THREAD);
909 Exceptions::fthrow(THREAD_AND_LOCATION,
910 vmSymbols::java_lang_NoClassDefFoundError(),
911 "Class %s, or one of its supertypes, failed class initialization",
912 external_name());
913 return false;
914 }
915 // return if already verified
916 if (is_linked()) {
917 return true;
918 }
919
920 // Timing
921 // timer handles recursion
922 JavaThread* jt = THREAD;
923
924 // link super class before linking this class
925 Klass* super_klass = super();
926 if (super_klass != nullptr) {
927 if (super_klass->is_interface()) { // check if super class is an interface
928 ResourceMark rm(THREAD);
929 Exceptions::fthrow(
930 THREAD_AND_LOCATION,
931 vmSymbols::java_lang_IncompatibleClassChangeError(),
932 "class %s has interface %s as super class",
933 external_name(),
934 super_klass->external_name()
935 );
936 return false;
937 }
938
939 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
940 ik_super->link_class_impl(CHECK_false);
941 }
942
943 // link all interfaces implemented by this class before linking this class
944 Array<InstanceKlass*>* interfaces = local_interfaces();
945 int num_interfaces = interfaces->length();
946 for (int index = 0; index < num_interfaces; index++) {
947 InstanceKlass* interk = interfaces->at(index);
948 interk->link_class_impl(CHECK_false);
949 }
950
951
952 // If a class declares a method that uses an inline class as an argument
953 // type or return inline type, this inline class must be loaded during the
954 // linking of this class because size and properties of the inline class
955 // must be known in order to be able to perform inline type optimizations.
956 // The implementation below is an approximation of this rule, the code
957 // iterates over all methods of the current class (including overridden
958 // methods), not only the methods declared by this class. This
959 // approximation makes the code simpler, and doesn't change the semantic
960 // because classes declaring methods overridden by the current class are
961 // linked (and have performed their own pre-loading) before the linking
962 // of the current class.
963
964
965 // Note:
966 // Inline class types are loaded during
967 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
968 // Inline class types used as element types for array creation
969 // are not pre-loaded. Their loading is triggered by either anewarray
970 // or multianewarray bytecodes.
971
972 // Could it be possible to do the following processing only if the
973 // class uses inline types?
974 if (EnableValhalla) {
975 ResourceMark rm(THREAD);
976 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
977 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) {
978 Symbol* sig = fs.signature();
979 TempNewSymbol s = Signature::strip_envelope(sig);
980 if (s != name()) {
981 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());
982 Klass* klass = SystemDictionary::resolve_or_fail(s,
983 Handle(THREAD, class_loader()), Handle(THREAD, protection_domain()), true,
984 CHECK_false);
985 if (HAS_PENDING_EXCEPTION) {
986 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s",
987 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string());
988 return false; // Exception is still pending
989 }
990 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded",
991 s->as_C_string(), name()->as_C_string());
992 assert(klass != nullptr, "Sanity check");
993 if (!klass->is_inline_klass()) {
994 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
995 err_msg("class %s expects class %s to be a value class but it is an identity class",
996 name()->as_C_string(), klass->external_name()), false);
997 }
998 if (klass->is_abstract()) {
999 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
1000 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class",
1001 name()->as_C_string(),
1002 InstanceKlass::cast(klass)->external_name()), false);
1003 }
1004 InstanceKlass* ik = InstanceKlass::cast(klass);
1005 if (!ik->is_implicitly_constructible()) {
1006 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
1007 err_msg("class %s is not implicitly constructible and it is used in a null restricted static field (not supported)",
1008 klass->external_name()), false);
1009 }
1010 // the inline_type_field_klasses_array might have been loaded with CDS, so update only if not already set and check consistency
1011 if (inline_type_field_klasses_array()->at(fs.index()) == nullptr) {
1012 set_inline_type_field_klass(fs.index(), InlineKlass::cast(ik));
1013 }
1014 assert(get_inline_type_field_klass(fs.index()) == ik, "Must match");
1015 } else {
1016 if (inline_type_field_klasses_array()->at(fs.index()) == nullptr) {
1017 set_inline_type_field_klass(fs.index(), InlineKlass::cast(this));
1018 }
1019 assert(get_inline_type_field_klass(fs.index()) == this, "Must match");
1020 }
1021 }
1022 }
1023
1024 // Aggressively preloading all classes from the LoadableDescriptors attribute
1025 if (loadable_descriptors() != nullptr) {
1026 HandleMark hm(THREAD);
1027 for (int i = 0; i < loadable_descriptors()->length(); i++) {
1028 Symbol* sig = constants()->symbol_at(loadable_descriptors()->at(i));
1029 TempNewSymbol class_name = Signature::strip_envelope(sig);
1030 if (class_name == name()) continue;
1031 log_info(class, preload)("Preloading class %s during linking of class %s because of the class is listed in the LoadableDescriptors attribute", sig->as_C_string(), name()->as_C_string());
1032 oop loader = class_loader();
1033 oop protection_domain = this->protection_domain();
1034 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1035 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD);
1036 if (HAS_PENDING_EXCEPTION) {
1037 CLEAR_PENDING_EXCEPTION;
1038 }
1039 if (klass != nullptr) {
1040 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) succeeded", class_name->as_C_string(), name()->as_C_string());
1041 if (!klass->is_inline_klass()) {
1042 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning
1043 log_warning(class, preload)("Preloading class %s during linking of class %s (cause: LoadableDescriptors attribute) but loaded class is not a value class", class_name->as_C_string(), name()->as_C_string());
1044 }
1045 } else {
1046 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) failed", class_name->as_C_string(), name()->as_C_string());
1047 }
1048 }
1049 }
1050 }
1051
1052 // in case the class is linked in the process of linking its superclasses
1053 if (is_linked()) {
1054 return true;
1055 }
1056
1057 // trace only the link time for this klass that includes
1058 // the verification time
1059 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1060 ClassLoader::perf_class_link_selftime(),
1061 ClassLoader::perf_classes_linked(),
1062 jt->get_thread_stat()->perf_recursion_counts_addr(),
1063 jt->get_thread_stat()->perf_timers_addr(),
1064 PerfClassTraceTime::CLASS_LINK);
1065
1066 // verification & rewriting
1067 {
1068 LockLinkState init_lock(this, jt);
1069
1070 // rewritten will have been set if loader constraint error found
1071 // on an earlier link attempt
1072 // don't verify or rewrite if already rewritten
1073 //
1074
1075 if (!is_linked()) {
1076 if (!is_rewritten()) {
1077 if (is_shared()) {
1078 assert(!verified_at_dump_time(), "must be");
1079 }
1080 {
1081 bool verify_ok = verify_code(THREAD);
1082 if (!verify_ok) {
1083 return false;
1084 }
1085 }
1086
1087 // Just in case a side-effect of verify linked this class already
1088 // (which can sometimes happen since the verifier loads classes
1089 // using custom class loaders, which are free to initialize things)
1090 if (is_linked()) {
1091 return true;
1092 }
1093
1094 // also sets rewritten
1095 rewrite_class(CHECK_false);
1096 } else if (is_shared()) {
1097 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1098 }
1099
1100 // relocate jsrs and link methods after they are all rewritten
1101 link_methods(CHECK_false);
1102
1103 // Initialize the vtable and interface table after
1104 // methods have been rewritten since rewrite may
1105 // fabricate new Method*s.
1106 // also does loader constraint checking
1107 //
1108 // initialize_vtable and initialize_itable need to be rerun
1109 // for a shared class if
1110 // 1) the class is loaded by custom class loader or
1111 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1112 // 3) the class was not verified during dump time
1113 bool need_init_table = true;
1114 if (is_shared() && verified_at_dump_time() &&
1115 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1116 need_init_table = false;
1117 }
1118 if (need_init_table) {
1119 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1120 itable().initialize_itable_and_check_constraints(CHECK_false);
1121 }
1122 #ifdef ASSERT
1123 vtable().verify(tty, true);
1124 // In case itable verification is ever added.
1125 // itable().verify(tty, true);
1126 #endif
1127 set_initialization_state_and_notify(linked, THREAD);
1128 if (JvmtiExport::should_post_class_prepare()) {
1129 JvmtiExport::post_class_prepare(THREAD, this);
1130 }
1131 }
1132 }
1133 return true;
1134 }
1135
1136 // Rewrite the byte codes of all of the methods of a class.
1137 // The rewriter must be called exactly once. Rewriting must happen after
1138 // verification but before the first method of the class is executed.
1139 void InstanceKlass::rewrite_class(TRAPS) {
1140 assert(is_loaded(), "must be loaded");
1141 if (is_rewritten()) {
1142 assert(is_shared(), "rewriting an unshared class?");
1143 return;
1144 }
1145 Rewriter::rewrite(this, CHECK);
1146 set_rewritten();
1147 }
1148
1149 // Now relocate and link method entry points after class is rewritten.
1150 // This is outside is_rewritten flag. In case of an exception, it can be
1151 // executed more than once.
1152 void InstanceKlass::link_methods(TRAPS) {
1153 int len = methods()->length();
1154 for (int i = len-1; i >= 0; i--) {
1155 methodHandle m(THREAD, methods()->at(i));
1156
1157 // Set up method entry points for compiler and interpreter .
1158 m->link_method(m, CHECK);
1159 }
1160 }
1161
1162 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1163 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1164 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1165 for (int i = 0; i < local_interfaces()->length(); ++i) {
1166 InstanceKlass* ik = local_interfaces()->at(i);
1167
1168 // Initialization is depth first search ie. we start with top of the inheritance tree
1169 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1170 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1171 if (ik->has_nonstatic_concrete_methods()) {
1172 ik->initialize_super_interfaces(CHECK);
1173 }
1174
1175 // Only initialize() interfaces that "declare" concrete methods.
1176 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1177 ik->initialize(CHECK);
1178 }
1179 }
1180 }
1181
1182 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1183 static InitializationErrorTable* _initialization_error_table;
1184
1185 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1186 // Create the same exception with a message indicating the thread name,
1187 // and the StackTraceElements.
1188 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1189 ResourceMark rm(current);
1190 if (init_error.is_null()) {
1191 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1192
1193 // We failed to create the new exception, most likely due to either out-of-memory or
1194 // a stackoverflow error. If the original exception was either of those then we save
1195 // the shared, pre-allocated, stackless, instance of that exception.
1196 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1197 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1198 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1199 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1200 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1201 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1202 } else {
1203 return;
1204 }
1205 }
1206
1207 MutexLocker ml(current, ClassInitError_lock);
1208 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1209 bool created;
1210 if (_initialization_error_table == nullptr) {
1211 _initialization_error_table = new (mtClass) InitializationErrorTable();
1212 }
1213 _initialization_error_table->put_if_absent(this, elem, &created);
1214 assert(created, "Initialization is single threaded");
1215 log_trace(class, init)("Initialization error added for class %s", external_name());
1216 }
1217
1218 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1219 MutexLocker ml(current, ClassInitError_lock);
1220 if (_initialization_error_table == nullptr) {
1221 return nullptr;
1222 }
1223 OopHandle* h = _initialization_error_table->get(this);
1224 return (h != nullptr) ? h->resolve() : nullptr;
1225 }
1226
1227 // Need to remove entries for unloaded classes.
1228 void InstanceKlass::clean_initialization_error_table() {
1229 struct InitErrorTableCleaner {
1230 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1231 if (!ik->is_loader_alive()) {
1232 h.release(Universe::vm_global());
1233 return true;
1234 } else {
1235 return false;
1236 }
1237 }
1238 };
1239
1240 assert_locked_or_safepoint(ClassInitError_lock);
1241 InitErrorTableCleaner cleaner;
1242 if (_initialization_error_table != nullptr) {
1243 _initialization_error_table->unlink(&cleaner);
1244 }
1245 }
1246
1247 void InstanceKlass::initialize_impl(TRAPS) {
1248 HandleMark hm(THREAD);
1249
1250 // Make sure klass is linked (verified) before initialization
1251 // A class could already be verified, since it has been reflected upon.
1252 link_class(CHECK);
1253
1254 DTRACE_CLASSINIT_PROBE(required, -1);
1255
1256 bool wait = false;
1257 bool throw_error = false;
1258
1259 JavaThread* jt = THREAD;
1260
1261 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1262
1263 // refer to the JVM book page 47 for description of steps
1264 // Step 1
1265 {
1266 MonitorLocker ml(jt, _init_monitor);
1267
1268 // Step 2
1269 while (is_being_initialized() && !is_init_thread(jt)) {
1270 if (debug_logging_enabled) {
1271 ResourceMark rm(jt);
1272 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1273 jt->name(), external_name(), init_thread_name());
1274 }
1275
1276 wait = true;
1277 jt->set_class_to_be_initialized(this);
1278 ml.wait();
1279 jt->set_class_to_be_initialized(nullptr);
1280 }
1281
1282 // Step 3
1283 if (is_being_initialized() && is_init_thread(jt)) {
1284 if (debug_logging_enabled) {
1285 ResourceMark rm(jt);
1286 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1287 jt->name(), external_name());
1288 }
1289 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1290 return;
1291 }
1292
1293 // Step 4
1294 if (is_initialized()) {
1295 if (debug_logging_enabled) {
1296 ResourceMark rm(jt);
1297 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1298 jt->name(), external_name());
1299 }
1300 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1301 return;
1302 }
1303
1304 // Step 5
1305 if (is_in_error_state()) {
1306 if (debug_logging_enabled) {
1307 ResourceMark rm(jt);
1308 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1309 jt->name(), external_name());
1310 }
1311 throw_error = true;
1312 } else {
1313
1314 // Step 6
1315 set_init_state(being_initialized);
1316 set_init_thread(jt);
1317 if (debug_logging_enabled) {
1318 ResourceMark rm(jt);
1319 log_debug(class, init)("Thread \"%s\" is initializing %s",
1320 jt->name(), external_name());
1321 }
1322 }
1323 }
1324
1325 // Throw error outside lock
1326 if (throw_error) {
1327 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1328 ResourceMark rm(THREAD);
1329 Handle cause(THREAD, get_initialization_error(THREAD));
1330
1331 stringStream ss;
1332 ss.print("Could not initialize class %s", external_name());
1333 if (cause.is_null()) {
1334 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1335 } else {
1336 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1337 ss.as_string(), cause);
1338 }
1339 }
1340
1341 // Pre-allocating an instance of the default value
1342 if (is_inline_klass()) {
1343 InlineKlass* vk = InlineKlass::cast(this);
1344 oop val = vk->allocate_instance(THREAD);
1345 if (HAS_PENDING_EXCEPTION) {
1346 Handle e(THREAD, PENDING_EXCEPTION);
1347 CLEAR_PENDING_EXCEPTION;
1348 {
1349 EXCEPTION_MARK;
1350 add_initialization_error(THREAD, e);
1351 // Locks object, set state, and notify all waiting threads
1352 set_initialization_state_and_notify(initialization_error, THREAD);
1353 CLEAR_PENDING_EXCEPTION;
1354 }
1355 THROW_OOP(e());
1356 }
1357 vk->set_default_value(val);
1358 }
1359
1360 // Step 7
1361 // Next, if C is a class rather than an interface, initialize it's super class and super
1362 // interfaces.
1363 if (!is_interface()) {
1364 Klass* super_klass = super();
1365 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1366 super_klass->initialize(THREAD);
1367 }
1368 // If C implements any interface that declares a non-static, concrete method,
1369 // the initialization of C triggers initialization of its super interfaces.
1370 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1371 // having a superinterface that declares, non-static, concrete methods
1372 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1373 initialize_super_interfaces(THREAD);
1374 }
1375
1376 // If any exceptions, complete abruptly, throwing the same exception as above.
1377 if (HAS_PENDING_EXCEPTION) {
1378 Handle e(THREAD, PENDING_EXCEPTION);
1379 CLEAR_PENDING_EXCEPTION;
1380 {
1381 EXCEPTION_MARK;
1382 add_initialization_error(THREAD, e);
1383 // Locks object, set state, and notify all waiting threads
1384 set_initialization_state_and_notify(initialization_error, THREAD);
1385 CLEAR_PENDING_EXCEPTION;
1386 }
1387 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1388 THROW_OOP(e());
1389 }
1390 }
1391
1392 // Step 8
1393 // Initialize classes of inline fields
1394 if (EnableValhalla) {
1395 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1396 if (fs.is_null_free_inline_type()) {
1397
1398 // inline type field klass array entries must have alreadyt been filed at load time or link time
1399 Klass* klass = get_inline_type_field_klass(fs.index());
1400
1401 InstanceKlass::cast(klass)->initialize(THREAD);
1402 if (fs.access_flags().is_static()) {
1403 if (java_mirror()->obj_field(fs.offset()) == nullptr) {
1404 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value());
1405 }
1406 }
1407
1408 if (HAS_PENDING_EXCEPTION) {
1409 Handle e(THREAD, PENDING_EXCEPTION);
1410 CLEAR_PENDING_EXCEPTION;
1411 {
1412 EXCEPTION_MARK;
1413 add_initialization_error(THREAD, e);
1414 // Locks object, set state, and notify all waiting threads
1415 set_initialization_state_and_notify(initialization_error, THREAD);
1416 CLEAR_PENDING_EXCEPTION;
1417 }
1418 THROW_OOP(e());
1419 }
1420 }
1421 }
1422 }
1423
1424
1425 // Step 9
1426 {
1427 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1428 if (class_initializer() != nullptr) {
1429 // Timer includes any side effects of class initialization (resolution,
1430 // etc), but not recursive entry into call_class_initializer().
1431 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1432 ClassLoader::perf_class_init_selftime(),
1433 ClassLoader::perf_classes_inited(),
1434 jt->get_thread_stat()->perf_recursion_counts_addr(),
1435 jt->get_thread_stat()->perf_timers_addr(),
1436 PerfClassTraceTime::CLASS_CLINIT);
1437 call_class_initializer(THREAD);
1438 } else {
1439 // The elapsed time is so small it's not worth counting.
1440 if (UsePerfData) {
1441 ClassLoader::perf_classes_inited()->inc();
1442 }
1443 call_class_initializer(THREAD);
1444 }
1445 }
1446
1447 // Step 10
1448 if (!HAS_PENDING_EXCEPTION) {
1449 set_initialization_state_and_notify(fully_initialized, THREAD);
1450 debug_only(vtable().verify(tty, true);)
1451 }
1452 else {
1453 // Step 11 and 12
1454 Handle e(THREAD, PENDING_EXCEPTION);
1455 CLEAR_PENDING_EXCEPTION;
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 EXCEPTION_MARK;
1461 add_initialization_error(THREAD, e);
1462 set_initialization_state_and_notify(initialization_error, THREAD);
1463 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1464 // JVMTI has already reported the pending exception
1465 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1466 JvmtiExport::clear_detected_exception(jt);
1467 }
1468 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1469 if (e->is_a(vmClasses::Error_klass())) {
1470 THROW_OOP(e());
1471 } else {
1472 JavaCallArguments args(e);
1473 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1474 vmSymbols::throwable_void_signature(),
1475 &args);
1476 }
1477 }
1478 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1479 }
1480
1481
1482 void InstanceKlass::set_initialization_state_and_notify(ClassState state, JavaThread* current) {
1483 MonitorLocker ml(current, _init_monitor);
1484
1485 if (state == linked && UseVtableBasedCHA && Universe::is_fully_initialized()) {
1486 DeoptimizationScope deopt_scope;
1487 {
1488 // Now mark all code that assumes the class is not linked.
1489 // Set state under the Compile_lock also.
1490 MutexLocker ml(current, Compile_lock);
1491
1492 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1493 set_init_state(state);
1494
1495 CodeCache::mark_dependents_on(&deopt_scope, this);
1496 }
1497 // Perform the deopt handshake outside Compile_lock.
1498 deopt_scope.deoptimize_marked();
1499 } else {
1500 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1501 set_init_state(state);
1502 }
1503 ml.notify_all();
1504 }
1505
1506 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1507 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1508 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1509 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1510
1511 // In case we are not using CHA based vtables we need to make sure the loaded
1512 // deopt is completed before anyone links this class.
1513 // Linking is done with _init_monitor held, by loading and deopting with it
1514 // held we make sure the deopt is completed before linking.
1515 if (!UseVtableBasedCHA) {
1516 init_monitor()->lock();
1517 }
1518
1519 DeoptimizationScope deopt_scope;
1520 {
1521 MutexLocker ml(current, Compile_lock);
1522
1523 set_init_state(InstanceKlass::loaded);
1524 // make sure init_state store is already done.
1525 // The compiler reads the hierarchy outside of the Compile_lock.
1526 // Access ordering is used to add to hierarchy.
1527
1528 // Link into hierarchy.
1529 append_to_sibling_list(); // add to superklass/sibling list
1530 process_interfaces(); // handle all "implements" declarations
1531
1532 // Now mark all code that depended on old class hierarchy.
1533 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1534 if (Universe::is_fully_initialized()) {
1535 CodeCache::mark_dependents_on(&deopt_scope, this);
1536 }
1537 }
1538 // Perform the deopt handshake outside Compile_lock.
1539 deopt_scope.deoptimize_marked();
1540
1541 if (!UseVtableBasedCHA) {
1542 init_monitor()->unlock();
1543 }
1544 }
1545
1546 InstanceKlass* InstanceKlass::implementor() const {
1547 InstanceKlass* volatile* ik = adr_implementor();
1548 if (ik == nullptr) {
1549 return nullptr;
1550 } else {
1551 // This load races with inserts, and therefore needs acquire.
1552 InstanceKlass* ikls = Atomic::load_acquire(ik);
1553 if (ikls != nullptr && !ikls->is_loader_alive()) {
1554 return nullptr; // don't return unloaded class
1555 } else {
1556 return ikls;
1557 }
1558 }
1559 }
1560
1561
1562 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1563 assert_locked_or_safepoint(Compile_lock);
1564 assert(is_interface(), "not interface");
1565 InstanceKlass* volatile* addr = adr_implementor();
1566 assert(addr != nullptr, "null addr");
1567 if (addr != nullptr) {
1568 Atomic::release_store(addr, ik);
1569 }
1570 }
1571
1572 int InstanceKlass::nof_implementors() const {
1573 InstanceKlass* ik = implementor();
1574 if (ik == nullptr) {
1575 return 0;
1576 } else if (ik != this) {
1577 return 1;
1578 } else {
1579 return 2;
1580 }
1581 }
1582
1583 // The embedded _implementor field can only record one implementor.
1584 // When there are more than one implementors, the _implementor field
1585 // is set to the interface Klass* itself. Following are the possible
1586 // values for the _implementor field:
1587 // null - no implementor
1588 // implementor Klass* - one implementor
1589 // self - more than one implementor
1590 //
1591 // The _implementor field only exists for interfaces.
1592 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1593 if (Universe::is_fully_initialized()) {
1594 assert_lock_strong(Compile_lock);
1595 }
1596 assert(is_interface(), "not interface");
1597 // Filter out my subinterfaces.
1598 // (Note: Interfaces are never on the subklass list.)
1599 if (ik->is_interface()) return;
1600
1601 // Filter out subclasses whose supers already implement me.
1602 // (Note: CHA must walk subclasses of direct implementors
1603 // in order to locate indirect implementors.)
1604 InstanceKlass* super_ik = ik->java_super();
1605 if (super_ik != nullptr && super_ik->implements_interface(this))
1606 // We only need to check one immediate superclass, since the
1607 // implements_interface query looks at transitive_interfaces.
1608 // Any supers of the super have the same (or fewer) transitive_interfaces.
1609 return;
1610
1611 InstanceKlass* iklass = implementor();
1612 if (iklass == nullptr) {
1613 set_implementor(ik);
1614 } else if (iklass != this && iklass != ik) {
1615 // There is already an implementor. Use itself as an indicator of
1616 // more than one implementors.
1617 set_implementor(this);
1618 }
1619
1620 // The implementor also implements the transitive_interfaces
1621 for (int index = 0; index < local_interfaces()->length(); index++) {
1622 local_interfaces()->at(index)->add_implementor(ik);
1623 }
1624 }
1625
1626 void InstanceKlass::init_implementor() {
1627 if (is_interface()) {
1628 set_implementor(nullptr);
1629 }
1630 }
1631
1632
1633 void InstanceKlass::process_interfaces() {
1634 // link this class into the implementors list of every interface it implements
1635 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1636 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1637 InstanceKlass* interf = local_interfaces()->at(i);
1638 assert(interf->is_interface(), "expected interface");
1639 interf->add_implementor(this);
1640 }
1641 }
1642
1643 bool InstanceKlass::can_be_primary_super_slow() const {
1644 if (is_interface())
1645 return false;
1646 else
1647 return Klass::can_be_primary_super_slow();
1648 }
1649
1650 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1651 Array<InstanceKlass*>* transitive_interfaces) {
1652 // The secondaries are the implemented interfaces.
1653 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1654 int num_secondaries = num_extra_slots + interfaces->length();
1655 if (num_secondaries == 0) {
1656 // Must share this for correct bootstrapping!
1657 set_secondary_supers(Universe::the_empty_klass_array());
1658 return nullptr;
1659 } else if (num_extra_slots == 0) {
1660 // The secondary super list is exactly the same as the transitive interfaces, so
1661 // let's use it instead of making a copy.
1662 // Redefine classes has to be careful not to delete this!
1663 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1664 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1665 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1666 return nullptr;
1667 } else {
1668 // Copy transitive interfaces to a temporary growable array to be constructed
1669 // into the secondary super list with extra slots.
1670 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1671 for (int i = 0; i < interfaces->length(); i++) {
1672 secondaries->push(interfaces->at(i));
1673 }
1674 return secondaries;
1675 }
1676 }
1677
1678 bool InstanceKlass::implements_interface(Klass* k) const {
1679 if (this == k) return true;
1680 assert(k->is_interface(), "should be an interface class");
1681 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1682 if (transitive_interfaces()->at(i) == k) {
1683 return true;
1684 }
1685 }
1686 return false;
1687 }
1688
1689 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1690 // Verify direct super interface
1691 if (this == k) return true;
1692 assert(k->is_interface(), "should be an interface class");
1693 for (int i = 0; i < local_interfaces()->length(); i++) {
1694 if (local_interfaces()->at(i) == k) {
1695 return true;
1696 }
1697 }
1698 return false;
1699 }
1700
1701 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1702 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1703 size_t size = objArrayOopDesc::object_size(length);
1704 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1705 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1706 /* do_zero */ true, CHECK_NULL);
1707 return o;
1708 }
1709
1710 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1711 if (TraceFinalizerRegistration) {
1712 tty->print("Registered ");
1713 i->print_value_on(tty);
1714 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1715 }
1716 instanceHandle h_i(THREAD, i);
1717 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1718 JavaValue result(T_VOID);
1719 JavaCallArguments args(h_i);
1720 methodHandle mh(THREAD, Universe::finalizer_register_method());
1721 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1722 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1723 return h_i();
1724 }
1725
1726 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1727 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1728 size_t size = size_helper(); // Query before forming handle.
1729
1730 instanceOop i;
1731
1732 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1733 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1734 i = register_finalizer(i, CHECK_NULL);
1735 }
1736 return i;
1737 }
1738
1739 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1740 Klass* k = java_lang_Class::as_Klass(java_class);
1741 if (k == nullptr) {
1742 ResourceMark rm(THREAD);
1743 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1744 }
1745 InstanceKlass* ik = cast(k);
1746 ik->check_valid_for_instantiation(false, CHECK_NULL);
1747 ik->initialize(CHECK_NULL);
1748 return ik->allocate_instance(THREAD);
1749 }
1750
1751 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1752 return instanceHandle(THREAD, allocate_instance(THREAD));
1753 }
1754
1755 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1756 if (is_interface() || is_abstract()) {
1757 ResourceMark rm(THREAD);
1758 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1759 : vmSymbols::java_lang_InstantiationException(), external_name());
1760 }
1761 if (this == vmClasses::Class_klass()) {
1762 ResourceMark rm(THREAD);
1763 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1764 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1765 }
1766 }
1767
1768 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1769 // Need load-acquire for lock-free read
1770 if (array_klasses_acquire() == nullptr) {
1771 ResourceMark rm(THREAD);
1772 JavaThread *jt = THREAD;
1773 {
1774 // Atomic creation of array_klasses
1775 MutexLocker ma(THREAD, MultiArray_lock);
1776
1777 // Check if update has already taken place
1778 if (array_klasses() == nullptr) {
1779 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this,
1780 false, CHECK_NULL);
1781 // use 'release' to pair with lock-free load
1782 release_set_array_klasses(k);
1783 }
1784 }
1785 }
1786 // array_klasses() will always be set at this point
1787 ArrayKlass* ak = array_klasses();
1788 return ak->array_klass(n, THREAD);
1789 }
1790
1791 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1792 // Need load-acquire for lock-free read
1793 ArrayKlass* ak = array_klasses_acquire();
1794 if (ak == nullptr) {
1795 return nullptr;
1796 } else {
1797 return ak->array_klass_or_null(n);
1798 }
1799 }
1800
1801 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1802 return array_klass(1, THREAD);
1803 }
1804
1805 ArrayKlass* InstanceKlass::array_klass_or_null() {
1806 return array_klass_or_null(1);
1807 }
1808
1809 static int call_class_initializer_counter = 0; // for debugging
1810
1811 Method* InstanceKlass::class_initializer() const {
1812 Method* clinit = find_method(
1813 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1814 if (clinit != nullptr && clinit->is_class_initializer()) {
1815 return clinit;
1816 }
1817 return nullptr;
1818 }
1819
1820 void InstanceKlass::call_class_initializer(TRAPS) {
1821 if (ReplayCompiles &&
1822 (ReplaySuppressInitializers == 1 ||
1823 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1824 // Hide the existence of the initializer for the purpose of replaying the compile
1825 return;
1826 }
1827
1828 #if INCLUDE_CDS
1829 // This is needed to ensure the consistency of the archived heap objects.
1830 if (has_archived_enum_objs()) {
1831 assert(is_shared(), "must be");
1832 bool initialized = HeapShared::initialize_enum_klass(this, CHECK);
1833 if (initialized) {
1834 return;
1835 }
1836 }
1837 #endif
1838
1839 methodHandle h_method(THREAD, class_initializer());
1840 assert(!is_initialized(), "we cannot initialize twice");
1841 LogTarget(Info, class, init) lt;
1842 if (lt.is_enabled()) {
1843 ResourceMark rm(THREAD);
1844 LogStream ls(lt);
1845 ls.print("%d Initializing ", call_class_initializer_counter++);
1846 name()->print_value_on(&ls);
1847 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1848 h_method() == nullptr ? "(no method)" : "", p2i(this),
1849 THREAD->name());
1850 }
1851 if (h_method() != nullptr) {
1852 JavaCallArguments args; // No arguments
1853 JavaValue result(T_VOID);
1854 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1855 }
1856 }
1857
1858
1859 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1860 InterpreterOopMap* entry_for) {
1861 // Lazily create the _oop_map_cache at first request
1862 // Lock-free access requires load_acquire.
1863 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1864 if (oop_map_cache == nullptr) {
1865 MutexLocker x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1866 // Check if _oop_map_cache was allocated while we were waiting for this lock
1867 if ((oop_map_cache = _oop_map_cache) == nullptr) {
1868 oop_map_cache = new OopMapCache();
1869 // Ensure _oop_map_cache is stable, since it is examined without a lock
1870 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1871 }
1872 }
1873 // _oop_map_cache is constant after init; lookup below does its own locking.
1874 oop_map_cache->lookup(method, bci, entry_for);
1875 }
1876
1877
1878 FieldInfo InstanceKlass::field(int index) const {
1879 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1880 if (fs.index() == index) {
1881 return fs.to_FieldInfo();
1882 }
1883 }
1884 fatal("Field not found");
1885 return FieldInfo();
1886 }
1887
1888 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1889 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1890 Symbol* f_name = fs.name();
1891 Symbol* f_sig = fs.signature();
1892 if (f_name == name && f_sig == sig) {
1893 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1894 return true;
1895 }
1896 }
1897 return false;
1898 }
1899
1900
1901 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1902 const int n = local_interfaces()->length();
1903 for (int i = 0; i < n; i++) {
1904 Klass* intf1 = local_interfaces()->at(i);
1905 assert(intf1->is_interface(), "just checking type");
1906 // search for field in current interface
1907 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1908 assert(fd->is_static(), "interface field must be static");
1909 return intf1;
1910 }
1911 // search for field in direct superinterfaces
1912 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1913 if (intf2 != nullptr) return intf2;
1914 }
1915 // otherwise field lookup fails
1916 return nullptr;
1917 }
1918
1919
1920 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1921 // search order according to newest JVM spec (5.4.3.2, p.167).
1922 // 1) search for field in current klass
1923 if (find_local_field(name, sig, fd)) {
1924 return const_cast<InstanceKlass*>(this);
1925 }
1926 // 2) search for field recursively in direct superinterfaces
1927 { Klass* intf = find_interface_field(name, sig, fd);
1928 if (intf != nullptr) return intf;
1929 }
1930 // 3) apply field lookup recursively if superclass exists
1931 { Klass* supr = super();
1932 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1933 }
1934 // 4) otherwise field lookup fails
1935 return nullptr;
1936 }
1937
1938
1939 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1940 // search order according to newest JVM spec (5.4.3.2, p.167).
1941 // 1) search for field in current klass
1942 if (find_local_field(name, sig, fd)) {
1943 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1944 }
1945 // 2) search for field recursively in direct superinterfaces
1946 if (is_static) {
1947 Klass* intf = find_interface_field(name, sig, fd);
1948 if (intf != nullptr) return intf;
1949 }
1950 // 3) apply field lookup recursively if superclass exists
1951 { Klass* supr = super();
1952 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1953 }
1954 // 4) otherwise field lookup fails
1955 return nullptr;
1956 }
1957
1958 bool InstanceKlass::contains_field_offset(int offset) {
1959 if (this->is_inline_klass()) {
1960 InlineKlass* vk = InlineKlass::cast(this);
1961 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->get_payload_size_in_bytes());
1962 } else {
1963 fieldDescriptor fd;
1964 return find_field_from_offset(offset, false, &fd);
1965 }
1966 }
1967
1968 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1969 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1970 if (fs.offset() == offset) {
1971 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1972 if (fd->is_static() == is_static) return true;
1973 }
1974 }
1975 return false;
1976 }
1977
1978
1979 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1980 Klass* klass = const_cast<InstanceKlass*>(this);
1981 while (klass != nullptr) {
1982 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1983 return true;
1984 }
1985 klass = klass->super();
1986 }
1987 return false;
1988 }
1989
1990
1991 void InstanceKlass::methods_do(void f(Method* method)) {
1992 // Methods aren't stable until they are loaded. This can be read outside
1993 // a lock through the ClassLoaderData for profiling
1994 // Redefined scratch classes are on the list and need to be cleaned
1995 if (!is_loaded() && !is_scratch_class()) {
1996 return;
1997 }
1998
1999 int len = methods()->length();
2000 for (int index = 0; index < len; index++) {
2001 Method* m = methods()->at(index);
2002 assert(m->is_method(), "must be method");
2003 f(m);
2004 }
2005 }
2006
2007
2008 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2009 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2010 if (fs.access_flags().is_static()) {
2011 fieldDescriptor& fd = fs.field_descriptor();
2012 cl->do_field(&fd);
2013 }
2014 }
2015 }
2016
2017
2018 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2019 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2020 if (fs.access_flags().is_static()) {
2021 fieldDescriptor& fd = fs.field_descriptor();
2022 f(&fd, mirror, CHECK);
2023 }
2024 }
2025 }
2026
2027 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2028 InstanceKlass* super = superklass();
2029 if (super != nullptr) {
2030 super->do_nonstatic_fields(cl);
2031 }
2032 fieldDescriptor fd;
2033 int length = java_fields_count();
2034 for (int i = 0; i < length; i += 1) {
2035 fd.reinitialize(this, i);
2036 if (!fd.is_static()) {
2037 cl->do_field(&fd);
2038 }
2039 }
2040 }
2041
2042 // first in Pair is offset, second is index.
2043 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2044 return a->first - b->first;
2045 }
2046
2047 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2048 InstanceKlass* super = superklass();
2049 if (super != nullptr) {
2050 super->print_nonstatic_fields(cl);
2051 }
2052 ResourceMark rm;
2053 fieldDescriptor fd;
2054 // In DebugInfo nonstatic fields are sorted by offset.
2055 GrowableArray<Pair<int,int> > fields_sorted;
2056 int i = 0;
2057 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2058 if (!fs.access_flags().is_static()) {
2059 fd = fs.field_descriptor();
2060 Pair<int,int> f(fs.offset(), fs.index());
2061 fields_sorted.push(f);
2062 i++;
2063 }
2064 }
2065 if (i > 0) {
2066 int length = i;
2067 assert(length == fields_sorted.length(), "duh");
2068 fields_sorted.sort(compare_fields_by_offset);
2069 for (int i = 0; i < length; i++) {
2070 fd.reinitialize(this, fields_sorted.at(i).second);
2071 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2072 cl->do_field(&fd);
2073 }
2074 }
2075 }
2076
2077 #ifdef ASSERT
2078 static int linear_search(const Array<Method*>* methods,
2079 const Symbol* name,
2080 const Symbol* signature) {
2081 const int len = methods->length();
2082 for (int index = 0; index < len; index++) {
2083 const Method* const m = methods->at(index);
2084 assert(m->is_method(), "must be method");
2085 if (m->signature() == signature && m->name() == name) {
2086 return index;
2087 }
2088 }
2089 return -1;
2090 }
2091 #endif
2092
2093 bool InstanceKlass::_disable_method_binary_search = false;
2094
2095 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2096 int len = methods->length();
2097 int l = 0;
2098 int h = len - 1;
2099 while (l <= h) {
2100 Method* m = methods->at(l);
2101 if (m->name() == name) {
2102 return l;
2103 }
2104 l++;
2105 }
2106 return -1;
2107 }
2108
2109 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2110 if (_disable_method_binary_search) {
2111 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2112 // At the final stage of dynamic dumping, the methods array may not be sorted
2113 // by ascending addresses of their names, so we can't use binary search anymore.
2114 // However, methods with the same name are still laid out consecutively inside the
2115 // methods array, so let's look for the first one that matches.
2116 return linear_search(methods, name);
2117 }
2118
2119 int len = methods->length();
2120 int l = 0;
2121 int h = len - 1;
2122
2123 // methods are sorted by ascending addresses of their names, so do binary search
2124 while (l <= h) {
2125 int mid = (l + h) >> 1;
2126 Method* m = methods->at(mid);
2127 assert(m->is_method(), "must be method");
2128 int res = m->name()->fast_compare(name);
2129 if (res == 0) {
2130 return mid;
2131 } else if (res < 0) {
2132 l = mid + 1;
2133 } else {
2134 h = mid - 1;
2135 }
2136 }
2137 return -1;
2138 }
2139
2140 // find_method looks up the name/signature in the local methods array
2141 Method* InstanceKlass::find_method(const Symbol* name,
2142 const Symbol* signature) const {
2143 return find_method_impl(name, signature,
2144 OverpassLookupMode::find,
2145 StaticLookupMode::find,
2146 PrivateLookupMode::find);
2147 }
2148
2149 Method* InstanceKlass::find_method_impl(const Symbol* name,
2150 const Symbol* signature,
2151 OverpassLookupMode overpass_mode,
2152 StaticLookupMode static_mode,
2153 PrivateLookupMode private_mode) const {
2154 return InstanceKlass::find_method_impl(methods(),
2155 name,
2156 signature,
2157 overpass_mode,
2158 static_mode,
2159 private_mode);
2160 }
2161
2162 // find_instance_method looks up the name/signature in the local methods array
2163 // and skips over static methods
2164 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2165 const Symbol* name,
2166 const Symbol* signature,
2167 PrivateLookupMode private_mode) {
2168 Method* const meth = InstanceKlass::find_method_impl(methods,
2169 name,
2170 signature,
2171 OverpassLookupMode::find,
2172 StaticLookupMode::skip,
2173 private_mode);
2174 assert(((meth == nullptr) || !meth->is_static()),
2175 "find_instance_method should have skipped statics");
2176 return meth;
2177 }
2178
2179 // find_instance_method looks up the name/signature in the local methods array
2180 // and skips over static methods
2181 Method* InstanceKlass::find_instance_method(const Symbol* name,
2182 const Symbol* signature,
2183 PrivateLookupMode private_mode) const {
2184 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2185 }
2186
2187 // Find looks up the name/signature in the local methods array
2188 // and filters on the overpass, static and private flags
2189 // This returns the first one found
2190 // note that the local methods array can have up to one overpass, one static
2191 // and one instance (private or not) with the same name/signature
2192 Method* InstanceKlass::find_local_method(const Symbol* name,
2193 const Symbol* signature,
2194 OverpassLookupMode overpass_mode,
2195 StaticLookupMode static_mode,
2196 PrivateLookupMode private_mode) const {
2197 return InstanceKlass::find_method_impl(methods(),
2198 name,
2199 signature,
2200 overpass_mode,
2201 static_mode,
2202 private_mode);
2203 }
2204
2205 // Find looks up the name/signature in the local methods array
2206 // and filters on the overpass, static and private flags
2207 // This returns the first one found
2208 // note that the local methods array can have up to one overpass, one static
2209 // and one instance (private or not) with the same name/signature
2210 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2211 const Symbol* name,
2212 const Symbol* signature,
2213 OverpassLookupMode overpass_mode,
2214 StaticLookupMode static_mode,
2215 PrivateLookupMode private_mode) {
2216 return InstanceKlass::find_method_impl(methods,
2217 name,
2218 signature,
2219 overpass_mode,
2220 static_mode,
2221 private_mode);
2222 }
2223
2224 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2225 const Symbol* name,
2226 const Symbol* signature) {
2227 return InstanceKlass::find_method_impl(methods,
2228 name,
2229 signature,
2230 OverpassLookupMode::find,
2231 StaticLookupMode::find,
2232 PrivateLookupMode::find);
2233 }
2234
2235 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2236 const Symbol* name,
2237 const Symbol* signature,
2238 OverpassLookupMode overpass_mode,
2239 StaticLookupMode static_mode,
2240 PrivateLookupMode private_mode) {
2241 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2242 return hit >= 0 ? methods->at(hit): nullptr;
2243 }
2244
2245 // true if method matches signature and conforms to skipping_X conditions.
2246 static bool method_matches(const Method* m,
2247 const Symbol* signature,
2248 bool skipping_overpass,
2249 bool skipping_static,
2250 bool skipping_private) {
2251 return ((m->signature() == signature) &&
2252 (!skipping_overpass || !m->is_overpass()) &&
2253 (!skipping_static || !m->is_static()) &&
2254 (!skipping_private || !m->is_private()));
2255 }
2256
2257 // Used directly for default_methods to find the index into the
2258 // default_vtable_indices, and indirectly by find_method
2259 // find_method_index looks in the local methods array to return the index
2260 // of the matching name/signature. If, overpass methods are being ignored,
2261 // the search continues to find a potential non-overpass match. This capability
2262 // is important during method resolution to prefer a static method, for example,
2263 // over an overpass method.
2264 // There is the possibility in any _method's array to have the same name/signature
2265 // for a static method, an overpass method and a local instance method
2266 // To correctly catch a given method, the search criteria may need
2267 // to explicitly skip the other two. For local instance methods, it
2268 // is often necessary to skip private methods
2269 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2270 const Symbol* name,
2271 const Symbol* signature,
2272 OverpassLookupMode overpass_mode,
2273 StaticLookupMode static_mode,
2274 PrivateLookupMode private_mode) {
2275 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2276 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2277 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2278 const int hit = quick_search(methods, name);
2279 if (hit != -1) {
2280 const Method* const m = methods->at(hit);
2281
2282 // Do linear search to find matching signature. First, quick check
2283 // for common case, ignoring overpasses if requested.
2284 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2285 return hit;
2286 }
2287
2288 // search downwards through overloaded methods
2289 int i;
2290 for (i = hit - 1; i >= 0; --i) {
2291 const Method* const m = methods->at(i);
2292 assert(m->is_method(), "must be method");
2293 if (m->name() != name) {
2294 break;
2295 }
2296 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2297 return i;
2298 }
2299 }
2300 // search upwards
2301 for (i = hit + 1; i < methods->length(); ++i) {
2302 const Method* const m = methods->at(i);
2303 assert(m->is_method(), "must be method");
2304 if (m->name() != name) {
2305 break;
2306 }
2307 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2308 return i;
2309 }
2310 }
2311 // not found
2312 #ifdef ASSERT
2313 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2314 linear_search(methods, name, signature);
2315 assert(-1 == index, "binary search should have found entry %d", index);
2316 #endif
2317 }
2318 return -1;
2319 }
2320
2321 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2322 return find_method_by_name(methods(), name, end);
2323 }
2324
2325 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2326 const Symbol* name,
2327 int* end_ptr) {
2328 assert(end_ptr != nullptr, "just checking");
2329 int start = quick_search(methods, name);
2330 int end = start + 1;
2331 if (start != -1) {
2332 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2333 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2334 *end_ptr = end;
2335 return start;
2336 }
2337 return -1;
2338 }
2339
2340 // uncached_lookup_method searches both the local class methods array and all
2341 // superclasses methods arrays, skipping any overpass methods in superclasses,
2342 // and possibly skipping private methods.
2343 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2344 const Symbol* signature,
2345 OverpassLookupMode overpass_mode,
2346 PrivateLookupMode private_mode) const {
2347 OverpassLookupMode overpass_local_mode = overpass_mode;
2348 const Klass* klass = this;
2349 while (klass != nullptr) {
2350 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2351 signature,
2352 overpass_local_mode,
2353 StaticLookupMode::find,
2354 private_mode);
2355 if (method != nullptr) {
2356 return method;
2357 }
2358 if (name == vmSymbols::object_initializer_name()) {
2359 break; // <init> is never inherited
2360 }
2361 klass = klass->super();
2362 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2363 }
2364 return nullptr;
2365 }
2366
2367 #ifdef ASSERT
2368 // search through class hierarchy and return true if this class or
2369 // one of the superclasses was redefined
2370 bool InstanceKlass::has_redefined_this_or_super() const {
2371 const Klass* klass = this;
2372 while (klass != nullptr) {
2373 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2374 return true;
2375 }
2376 klass = klass->super();
2377 }
2378 return false;
2379 }
2380 #endif
2381
2382 // lookup a method in the default methods list then in all transitive interfaces
2383 // Do NOT return private or static methods
2384 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2385 Symbol* signature) const {
2386 Method* m = nullptr;
2387 if (default_methods() != nullptr) {
2388 m = find_method(default_methods(), name, signature);
2389 }
2390 // Look up interfaces
2391 if (m == nullptr) {
2392 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2393 }
2394 return m;
2395 }
2396
2397 // lookup a method in all the interfaces that this class implements
2398 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2399 // They should only be found in the initial InterfaceMethodRef
2400 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2401 Symbol* signature,
2402 DefaultsLookupMode defaults_mode) const {
2403 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2404 int num_ifs = all_ifs->length();
2405 InstanceKlass *ik = nullptr;
2406 for (int i = 0; i < num_ifs; i++) {
2407 ik = all_ifs->at(i);
2408 Method* m = ik->lookup_method(name, signature);
2409 if (m != nullptr && m->is_public() && !m->is_static() &&
2410 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2411 return m;
2412 }
2413 }
2414 return nullptr;
2415 }
2416
2417 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2418 :_st(st), _verbose(verbose) {
2419 ResourceMark rm;
2420 _st->print("%-18s ", "KlassAddr");
2421 _st->print("%-4s ", "Size");
2422 _st->print("%-20s ", "State");
2423 _st->print("%-7s ", "Flags");
2424 _st->print("%-5s ", "ClassName");
2425 _st->cr();
2426 }
2427
2428 void PrintClassClosure::do_klass(Klass* k) {
2429 ResourceMark rm;
2430 // klass pointer
2431 _st->print(PTR_FORMAT " ", p2i(k));
2432 // klass size
2433 _st->print("%4d ", k->size());
2434 // initialization state
2435 if (k->is_instance_klass()) {
2436 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2437 } else {
2438 _st->print("%-20s ","");
2439 }
2440 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2441 char buf[10];
2442 int i = 0;
2443 if (k->has_finalizer()) buf[i++] = 'F';
2444 if (k->is_instance_klass()) {
2445 InstanceKlass* ik = InstanceKlass::cast(k);
2446 if (ik->has_final_method()) buf[i++] = 'f';
2447 if (ik->is_rewritten()) buf[i++] = 'W';
2448 if (ik->is_contended()) buf[i++] = 'C';
2449 if (ik->has_been_redefined()) buf[i++] = 'R';
2450 if (ik->is_shared()) buf[i++] = 'S';
2451 }
2452 buf[i++] = '\0';
2453 _st->print("%-7s ", buf);
2454 // klass name
2455 _st->print("%-5s ", k->external_name());
2456 // end
2457 _st->cr();
2458 if (_verbose) {
2459 k->print_on(_st);
2460 }
2461 }
2462
2463 /* jni_id_for for jfieldIds only */
2464 JNIid* InstanceKlass::jni_id_for(int offset) {
2465 MutexLocker ml(JfieldIdCreation_lock);
2466 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2467 if (probe == nullptr) {
2468 // Allocate new static field identifier
2469 probe = new JNIid(this, offset, jni_ids());
2470 set_jni_ids(probe);
2471 }
2472 return probe;
2473 }
2474
2475 u2 InstanceKlass::enclosing_method_data(int offset) const {
2476 const Array<jushort>* const inner_class_list = inner_classes();
2477 if (inner_class_list == nullptr) {
2478 return 0;
2479 }
2480 const int length = inner_class_list->length();
2481 if (length % inner_class_next_offset == 0) {
2482 return 0;
2483 }
2484 const int index = length - enclosing_method_attribute_size;
2485 assert(offset < enclosing_method_attribute_size, "invalid offset");
2486 return inner_class_list->at(index + offset);
2487 }
2488
2489 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2490 u2 method_index) {
2491 Array<jushort>* inner_class_list = inner_classes();
2492 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2493 int length = inner_class_list->length();
2494 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2495 int index = length - enclosing_method_attribute_size;
2496 inner_class_list->at_put(
2497 index + enclosing_method_class_index_offset, class_index);
2498 inner_class_list->at_put(
2499 index + enclosing_method_method_index_offset, method_index);
2500 }
2501 }
2502
2503 // Lookup or create a jmethodID.
2504 // This code is called by the VMThread and JavaThreads so the
2505 // locking has to be done very carefully to avoid deadlocks
2506 // and/or other cache consistency problems.
2507 //
2508 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2509 size_t idnum = (size_t)method_h->method_idnum();
2510 jmethodID* jmeths = methods_jmethod_ids_acquire();
2511 size_t length = 0;
2512 jmethodID id = nullptr;
2513
2514 // We use a double-check locking idiom here because this cache is
2515 // performance sensitive. In the normal system, this cache only
2516 // transitions from null to non-null which is safe because we use
2517 // release_set_methods_jmethod_ids() to advertise the new cache.
2518 // A partially constructed cache should never be seen by a racing
2519 // thread. We also use release_store() to save a new jmethodID
2520 // in the cache so a partially constructed jmethodID should never be
2521 // seen either. Cache reads of existing jmethodIDs proceed without a
2522 // lock, but cache writes of a new jmethodID requires uniqueness and
2523 // creation of the cache itself requires no leaks so a lock is
2524 // generally acquired in those two cases.
2525 //
2526 // If the RedefineClasses() API has been used, then this cache can
2527 // grow and we'll have transitions from non-null to bigger non-null.
2528 // Cache creation requires no leaks and we require safety between all
2529 // cache accesses and freeing of the old cache so a lock is generally
2530 // acquired when the RedefineClasses() API has been used.
2531
2532 if (jmeths != nullptr) {
2533 // the cache already exists
2534 if (!idnum_can_increment()) {
2535 // the cache can't grow so we can just get the current values
2536 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2537 } else {
2538 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2539 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2540 }
2541 }
2542 // implied else:
2543 // we need to allocate a cache so default length and id values are good
2544
2545 if (jmeths == nullptr || // no cache yet
2546 length <= idnum || // cache is too short
2547 id == nullptr) { // cache doesn't contain entry
2548
2549 // This function can be called by the VMThread or GC worker threads so we
2550 // have to do all things that might block on a safepoint before grabbing the lock.
2551 // Otherwise, we can deadlock with the VMThread or have a cache
2552 // consistency issue. These vars keep track of what we might have
2553 // to free after the lock is dropped.
2554 jmethodID to_dealloc_id = nullptr;
2555 jmethodID* to_dealloc_jmeths = nullptr;
2556
2557 // may not allocate new_jmeths or use it if we allocate it
2558 jmethodID* new_jmeths = nullptr;
2559 if (length <= idnum) {
2560 // allocate a new cache that might be used
2561 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2562 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2563 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2564 // cache size is stored in element[0], other elements offset by one
2565 new_jmeths[0] = (jmethodID)size;
2566 }
2567
2568 // allocate a new jmethodID that might be used
2569 {
2570 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2571 jmethodID new_id = nullptr;
2572 if (method_h->is_old() && !method_h->is_obsolete()) {
2573 // The method passed in is old (but not obsolete), we need to use the current version
2574 Method* current_method = method_with_idnum((int)idnum);
2575 assert(current_method != nullptr, "old and but not obsolete, so should exist");
2576 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2577 } else {
2578 // It is the current version of the method or an obsolete method,
2579 // use the version passed in
2580 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2581 }
2582
2583 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2584 &to_dealloc_id, &to_dealloc_jmeths);
2585 }
2586
2587 // The lock has been dropped so we can free resources.
2588 // Free up either the old cache or the new cache if we allocated one.
2589 if (to_dealloc_jmeths != nullptr) {
2590 FreeHeap(to_dealloc_jmeths);
2591 }
2592 // free up the new ID since it wasn't needed
2593 if (to_dealloc_id != nullptr) {
2594 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2595 }
2596 }
2597 return id;
2598 }
2599
2600 // Figure out how many jmethodIDs haven't been allocated, and make
2601 // sure space for them is pre-allocated. This makes getting all
2602 // method ids much, much faster with classes with more than 8
2603 // methods, and has a *substantial* effect on performance with jvmti
2604 // code that loads all jmethodIDs for all classes.
2605 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2606 int new_jmeths = 0;
2607 int length = methods()->length();
2608 for (int index = start_offset; index < length; index++) {
2609 Method* m = methods()->at(index);
2610 jmethodID id = m->find_jmethod_id_or_null();
2611 if (id == nullptr) {
2612 new_jmeths++;
2613 }
2614 }
2615 if (new_jmeths != 0) {
2616 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2617 }
2618 }
2619
2620 // Common code to fetch the jmethodID from the cache or update the
2621 // cache with the new jmethodID. This function should never do anything
2622 // that causes the caller to go to a safepoint or we can deadlock with
2623 // the VMThread or have cache consistency issues.
2624 //
2625 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2626 size_t idnum, jmethodID new_id,
2627 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2628 jmethodID** to_dealloc_jmeths_p) {
2629 assert(new_id != nullptr, "sanity check");
2630 assert(to_dealloc_id_p != nullptr, "sanity check");
2631 assert(to_dealloc_jmeths_p != nullptr, "sanity check");
2632 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2633
2634 // reacquire the cache - we are locked, single threaded or at a safepoint
2635 jmethodID* jmeths = methods_jmethod_ids_acquire();
2636 jmethodID id = nullptr;
2637 size_t length = 0;
2638
2639 if (jmeths == nullptr || // no cache yet
2640 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2641 if (jmeths != nullptr) {
2642 // copy any existing entries from the old cache
2643 for (size_t index = 0; index < length; index++) {
2644 new_jmeths[index+1] = jmeths[index+1];
2645 }
2646 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2647 }
2648 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2649 } else {
2650 // fetch jmethodID (if any) from the existing cache
2651 id = jmeths[idnum+1];
2652 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2653 }
2654 if (id == nullptr) {
2655 // No matching jmethodID in the existing cache or we have a new
2656 // cache or we just grew the cache. This cache write is done here
2657 // by the first thread to win the foot race because a jmethodID
2658 // needs to be unique once it is generally available.
2659 id = new_id;
2660
2661 // The jmethodID cache can be read while unlocked so we have to
2662 // make sure the new jmethodID is complete before installing it
2663 // in the cache.
2664 Atomic::release_store(&jmeths[idnum+1], id);
2665 } else {
2666 *to_dealloc_id_p = new_id; // save new id for later delete
2667 }
2668 return id;
2669 }
2670
2671
2672 // Common code to get the jmethodID cache length and the jmethodID
2673 // value at index idnum if there is one.
2674 //
2675 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2676 size_t idnum, size_t *length_p, jmethodID* id_p) {
2677 assert(cache != nullptr, "sanity check");
2678 assert(length_p != nullptr, "sanity check");
2679 assert(id_p != nullptr, "sanity check");
2680
2681 // cache size is stored in element[0], other elements offset by one
2682 *length_p = (size_t)cache[0];
2683 if (*length_p <= idnum) { // cache is too short
2684 *id_p = nullptr;
2685 } else {
2686 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2687 }
2688 }
2689
2690
2691 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2692 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2693 size_t idnum = (size_t)method->method_idnum();
2694 jmethodID* jmeths = methods_jmethod_ids_acquire();
2695 size_t length; // length assigned as debugging crumb
2696 jmethodID id = nullptr;
2697 if (jmeths != nullptr && // If there is a cache
2698 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2699 id = jmeths[idnum+1]; // Look up the id (may be null)
2700 }
2701 return id;
2702 }
2703
2704 inline DependencyContext InstanceKlass::dependencies() {
2705 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2706 return dep_context;
2707 }
2708
2709 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2710 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2711 }
2712
2713 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2714 dependencies().add_dependent_nmethod(nm);
2715 }
2716
2717 void InstanceKlass::clean_dependency_context() {
2718 dependencies().clean_unloading_dependents();
2719 }
2720
2721 #ifndef PRODUCT
2722 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2723 dependencies().print_dependent_nmethods(verbose);
2724 }
2725
2726 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2727 return dependencies().is_dependent_nmethod(nm);
2728 }
2729 #endif //PRODUCT
2730
2731 void InstanceKlass::clean_weak_instanceklass_links() {
2732 clean_implementors_list();
2733 clean_method_data();
2734 }
2735
2736 void InstanceKlass::clean_implementors_list() {
2737 assert(is_loader_alive(), "this klass should be live");
2738 if (is_interface()) {
2739 assert (ClassUnloading, "only called for ClassUnloading");
2740 for (;;) {
2741 // Use load_acquire due to competing with inserts
2742 InstanceKlass* volatile* iklass = adr_implementor();
2743 assert(iklass != nullptr, "Klass must not be null");
2744 InstanceKlass* impl = Atomic::load_acquire(iklass);
2745 if (impl != nullptr && !impl->is_loader_alive()) {
2746 // null this field, might be an unloaded instance klass or null
2747 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2748 // Successfully unlinking implementor.
2749 if (log_is_enabled(Trace, class, unload)) {
2750 ResourceMark rm;
2751 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2752 }
2753 return;
2754 }
2755 } else {
2756 return;
2757 }
2758 }
2759 }
2760 }
2761
2762 void InstanceKlass::clean_method_data() {
2763 for (int m = 0; m < methods()->length(); m++) {
2764 MethodData* mdo = methods()->at(m)->method_data();
2765 if (mdo != nullptr) {
2766 mdo->clean_method_data(/*always_clean*/false);
2767 }
2768 }
2769 }
2770
2771 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2772 Klass::metaspace_pointers_do(it);
2773
2774 if (log_is_enabled(Trace, cds)) {
2775 ResourceMark rm;
2776 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2777 }
2778
2779 it->push(&_annotations);
2780 it->push((Klass**)&_array_klasses);
2781 if (!is_rewritten()) {
2782 it->push(&_constants, MetaspaceClosure::_writable);
2783 } else {
2784 it->push(&_constants);
2785 }
2786 it->push(&_inner_classes);
2787 #if INCLUDE_JVMTI
2788 it->push(&_previous_versions);
2789 #endif
2790 #if INCLUDE_CDS
2791 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2792 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2793 // be writable. The length check on the _methods is necessary because classes which
2794 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2795 if (_methods != nullptr && _methods->length() > 0 &&
2796 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2797 // To handle jsr bytecode, new Method* maybe stored into _methods
2798 it->push(&_methods, MetaspaceClosure::_writable);
2799 } else {
2800 #endif
2801 it->push(&_methods);
2802 #if INCLUDE_CDS
2803 }
2804 #endif
2805 it->push(&_default_methods);
2806 it->push(&_local_interfaces);
2807 it->push(&_transitive_interfaces);
2808 it->push(&_method_ordering);
2809 if (!is_rewritten()) {
2810 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2811 } else {
2812 it->push(&_default_vtable_indices);
2813 }
2814
2815 it->push(&_fieldinfo_stream);
2816 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2817 it->push(&_fields_status, MetaspaceClosure::_writable);
2818
2819 if (itable_length() > 0) {
2820 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2821 int method_table_offset_in_words = ioe->offset()/wordSize;
2822 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2823
2824 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2825 / itableOffsetEntry::size();
2826
2827 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2828 if (ioe->interface_klass() != nullptr) {
2829 it->push(ioe->interface_klass_addr());
2830 itableMethodEntry* ime = ioe->first_method_entry(this);
2831 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2832 for (int index = 0; index < n; index ++) {
2833 it->push(ime[index].method_addr());
2834 }
2835 }
2836 }
2837 }
2838
2839 it->push(&_nest_members);
2840 it->push(&_permitted_subclasses);
2841 it->push(&_loadable_descriptors);
2842 it->push(&_record_components);
2843
2844 it->push(&_inline_type_field_klasses, MetaspaceClosure::_writable);
2845 it->push(&_null_marker_offsets);
2846 }
2847
2848 #if INCLUDE_CDS
2849 void InstanceKlass::remove_unshareable_info() {
2850
2851 if (is_linked()) {
2852 assert(can_be_verified_at_dumptime(), "must be");
2853 // Remember this so we can avoid walking the hierarchy at runtime.
2854 set_verified_at_dump_time();
2855 }
2856
2857 Klass::remove_unshareable_info();
2858
2859 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2860 // Classes are attempted to link during dumping and may fail,
2861 // but these classes are still in the dictionary and class list in CLD.
2862 // If the class has failed verification, there is nothing else to remove.
2863 return;
2864 }
2865
2866 // Reset to the 'allocated' state to prevent any premature accessing to
2867 // a shared class at runtime while the class is still being loaded and
2868 // restored. A class' init_state is set to 'loaded' at runtime when it's
2869 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2870 _init_state = allocated;
2871
2872 { // Otherwise this needs to take out the Compile_lock.
2873 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2874 init_implementor();
2875 }
2876
2877 constants()->remove_unshareable_info();
2878
2879 for (int i = 0; i < methods()->length(); i++) {
2880 Method* m = methods()->at(i);
2881 m->remove_unshareable_info();
2882 }
2883
2884 // do array classes also.
2885 if (array_klasses() != nullptr) {
2886 array_klasses()->remove_unshareable_info();
2887 }
2888
2889 // These are not allocated from metaspace. They are safe to set to nullptr.
2890 _source_debug_extension = nullptr;
2891 _dep_context = nullptr;
2892 _osr_nmethods_head = nullptr;
2893 #if INCLUDE_JVMTI
2894 _breakpoints = nullptr;
2895 _previous_versions = nullptr;
2896 _cached_class_file = nullptr;
2897 _jvmti_cached_class_field_map = nullptr;
2898 #endif
2899
2900 _init_thread = nullptr;
2901 _methods_jmethod_ids = nullptr;
2902 _jni_ids = nullptr;
2903 _oop_map_cache = nullptr;
2904 // clear _nest_host to ensure re-load at runtime
2905 _nest_host = nullptr;
2906 init_shared_package_entry();
2907 _dep_context_last_cleaned = 0;
2908 _init_monitor = nullptr;
2909
2910 remove_unshareable_flags();
2911 }
2912
2913 void InstanceKlass::remove_unshareable_flags() {
2914 // clear all the flags/stats that shouldn't be in the archived version
2915 assert(!is_scratch_class(), "must be");
2916 assert(!has_been_redefined(), "must be");
2917 #if INCLUDE_JVMTI
2918 set_is_being_redefined(false);
2919 #endif
2920 set_has_resolved_methods(false);
2921 }
2922
2923 void InstanceKlass::remove_java_mirror() {
2924 Klass::remove_java_mirror();
2925
2926 // do array classes also.
2927 if (array_klasses() != nullptr) {
2928 array_klasses()->remove_java_mirror();
2929 }
2930 }
2931
2932 void InstanceKlass::init_shared_package_entry() {
2933 assert(CDSConfig::is_dumping_archive(), "must be");
2934 #if !INCLUDE_CDS_JAVA_HEAP
2935 _package_entry = nullptr;
2936 #else
2937 if (CDSConfig::is_dumping_full_module_graph()) {
2938 if (is_shared_unregistered_class()) {
2939 _package_entry = nullptr;
2940 } else {
2941 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2942 }
2943 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2944 CDSConfig::is_loading_full_module_graph() &&
2945 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2946 // _package_entry is an archived package in the base archive. Leave it as is.
2947 } else {
2948 _package_entry = nullptr;
2949 }
2950 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2951 #endif
2952 }
2953
2954 void InstanceKlass::compute_has_loops_flag_for_methods() {
2955 Array<Method*>* methods = this->methods();
2956 for (int index = 0; index < methods->length(); ++index) {
2957 Method* m = methods->at(index);
2958 if (!m->is_overpass()) { // work around JDK-8305771
2959 m->compute_has_loops_flag();
2960 }
2961 }
2962 }
2963
2964 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2965 PackageEntry* pkg_entry, TRAPS) {
2966 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2967 // before the InstanceKlass is added to the SystemDictionary. Make
2968 // sure the current state is <loaded.
2969 assert(!is_loaded(), "invalid init state");
2970 assert(!shared_loading_failed(), "Must not try to load failed class again");
2971 set_package(loader_data, pkg_entry, CHECK);
2972 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2973
2974 if (is_inline_klass()) {
2975 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2976 }
2977
2978 Array<Method*>* methods = this->methods();
2979 int num_methods = methods->length();
2980 for (int index = 0; index < num_methods; ++index) {
2981 methods->at(index)->restore_unshareable_info(CHECK);
2982 }
2983 #if INCLUDE_JVMTI
2984 if (JvmtiExport::has_redefined_a_class()) {
2985 // Reinitialize vtable because RedefineClasses may have changed some
2986 // entries in this vtable for super classes so the CDS vtable might
2987 // point to old or obsolete entries. RedefineClasses doesn't fix up
2988 // vtables in the shared system dictionary, only the main one.
2989 // It also redefines the itable too so fix that too.
2990 // First fix any default methods that point to a super class that may
2991 // have been redefined.
2992 bool trace_name_printed = false;
2993 adjust_default_methods(&trace_name_printed);
2994 vtable().initialize_vtable();
2995 itable().initialize_itable();
2996 }
2997 #endif
2998
2999 // restore constant pool resolved references
3000 constants()->restore_unshareable_info(CHECK);
3001
3002 if (array_klasses() != nullptr) {
3003 // To get a consistent list of classes we need MultiArray_lock to ensure
3004 // array classes aren't observed while they are being restored.
3005 MutexLocker ml(MultiArray_lock);
3006 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
3007 // Array classes have null protection domain.
3008 // --> see ArrayKlass::complete_create_array_klass()
3009 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
3010 }
3011
3012 // Initialize @ValueBased class annotation
3013 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
3014 set_is_value_based();
3015 }
3016
3017 // restore the monitor
3018 _init_monitor = create_init_monitor("InstanceKlassInitMonitorRestored_lock");
3019 }
3020
3021 // Check if a class or any of its supertypes has a version older than 50.
3022 // CDS will not perform verification of old classes during dump time because
3023 // without changing the old verifier, the verification constraint cannot be
3024 // retrieved during dump time.
3025 // Verification of archived old classes will be performed during run time.
3026 bool InstanceKlass::can_be_verified_at_dumptime() const {
3027 if (MetaspaceShared::is_in_shared_metaspace(this)) {
3028 // This is a class that was dumped into the base archive, so we know
3029 // it was verified at dump time.
3030 return true;
3031 }
3032 if (major_version() < 50 /*JAVA_6_VERSION*/) {
3033 return false;
3034 }
3035 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
3036 return false;
3037 }
3038 Array<InstanceKlass*>* interfaces = local_interfaces();
3039 int len = interfaces->length();
3040 for (int i = 0; i < len; i++) {
3041 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
3042 return false;
3043 }
3044 }
3045 return true;
3046 }
3047
3048 bool InstanceKlass::methods_contain_jsr_bytecode() const {
3049 Thread* thread = Thread::current();
3050 for (int i = 0; i < _methods->length(); i++) {
3051 methodHandle m(thread, _methods->at(i));
3052 BytecodeStream bcs(m);
3053 while (!bcs.is_last_bytecode()) {
3054 Bytecodes::Code opcode = bcs.next();
3055 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
3056 return true;
3057 }
3058 }
3059 }
3060 return false;
3061 }
3062 #endif // INCLUDE_CDS
3063
3064 #if INCLUDE_JVMTI
3065 static void clear_all_breakpoints(Method* m) {
3066 m->clear_all_breakpoints();
3067 }
3068 #endif
3069
3070 void InstanceKlass::unload_class(InstanceKlass* ik) {
3071 // Release dependencies.
3072 ik->dependencies().remove_all_dependents();
3073
3074 // notify the debugger
3075 if (JvmtiExport::should_post_class_unload()) {
3076 JvmtiExport::post_class_unload(ik);
3077 }
3078
3079 // notify ClassLoadingService of class unload
3080 ClassLoadingService::notify_class_unloaded(ik);
3081
3082 SystemDictionaryShared::handle_class_unloading(ik);
3083
3084 if (log_is_enabled(Info, class, unload)) {
3085 ResourceMark rm;
3086 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3087 }
3088
3089 Events::log_class_unloading(Thread::current(), ik);
3090
3091 #if INCLUDE_JFR
3092 assert(ik != nullptr, "invariant");
3093 EventClassUnload event;
3094 event.set_unloadedClass(ik);
3095 event.set_definingClassLoader(ik->class_loader_data());
3096 event.commit();
3097 #endif
3098 }
3099
3100 static void method_release_C_heap_structures(Method* m) {
3101 m->release_C_heap_structures();
3102 }
3103
3104 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3105 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3106 // Clean up C heap
3107 Klass::release_C_heap_structures();
3108
3109 // Deallocate and call destructors for MDO mutexes
3110 if (release_sub_metadata) {
3111 methods_do(method_release_C_heap_structures);
3112 }
3113
3114 // Destroy the init_monitor
3115 delete _init_monitor;
3116
3117 // Deallocate oop map cache
3118 if (_oop_map_cache != nullptr) {
3119 delete _oop_map_cache;
3120 _oop_map_cache = nullptr;
3121 }
3122
3123 // Deallocate JNI identifiers for jfieldIDs
3124 JNIid::deallocate(jni_ids());
3125 set_jni_ids(nullptr);
3126
3127 jmethodID* jmeths = methods_jmethod_ids_acquire();
3128 if (jmeths != (jmethodID*)nullptr) {
3129 release_set_methods_jmethod_ids(nullptr);
3130 FreeHeap(jmeths);
3131 }
3132
3133 assert(_dep_context == nullptr,
3134 "dependencies should already be cleaned");
3135
3136 #if INCLUDE_JVMTI
3137 // Deallocate breakpoint records
3138 if (breakpoints() != 0x0) {
3139 methods_do(clear_all_breakpoints);
3140 assert(breakpoints() == 0x0, "should have cleared breakpoints");
3141 }
3142
3143 // deallocate the cached class file
3144 if (_cached_class_file != nullptr) {
3145 os::free(_cached_class_file);
3146 _cached_class_file = nullptr;
3147 }
3148 #endif
3149
3150 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3151
3152 if (release_sub_metadata) {
3153 constants()->release_C_heap_structures();
3154 }
3155 }
3156
3157 // The constant pool is on stack if any of the methods are executing or
3158 // referenced by handles.
3159 bool InstanceKlass::on_stack() const {
3160 return _constants->on_stack();
3161 }
3162
3163 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3164 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3165 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3166
3167 // minor and major version numbers of class file
3168 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3169 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3170 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3171 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3172
3173 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3174 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3175 if (ik->constants()->version() == version) {
3176 return ik;
3177 }
3178 }
3179 return nullptr;
3180 }
3181
3182 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3183 if (array == nullptr) {
3184 _source_debug_extension = nullptr;
3185 } else {
3186 // Adding one to the attribute length in order to store a null terminator
3187 // character could cause an overflow because the attribute length is
3188 // already coded with an u4 in the classfile, but in practice, it's
3189 // unlikely to happen.
3190 assert((length+1) > length, "Overflow checking");
3191 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3192 for (int i = 0; i < length; i++) {
3193 sde[i] = array[i];
3194 }
3195 sde[length] = '\0';
3196 _source_debug_extension = sde;
3197 }
3198 }
3199
3200 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3201 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3202 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3203
3204 const char* InstanceKlass::signature_name() const {
3205 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3206 }
3207
3208 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3209 // Get the internal name as a c string
3210 const char* src = (const char*) (name()->as_C_string());
3211 const int src_length = (int)strlen(src);
3212
3213 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3214
3215 // Add L or Q as type indicator
3216 int dest_index = 0;
3217 dest[dest_index++] = c;
3218
3219 // Add the actual class name
3220 for (int src_index = 0; src_index < src_length; ) {
3221 dest[dest_index++] = src[src_index++];
3222 }
3223
3224 if (is_hidden()) { // Replace the last '+' with a '.'.
3225 for (int index = (int)src_length; index > 0; index--) {
3226 if (dest[index] == '+') {
3227 dest[index] = JVM_SIGNATURE_DOT;
3228 break;
3229 }
3230 }
3231 }
3232
3233 // Add the semicolon and the null
3234 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3235 dest[dest_index] = '\0';
3236 return dest;
3237 }
3238
3239 ModuleEntry* InstanceKlass::module() const {
3240 if (is_hidden() &&
3241 in_unnamed_package() &&
3242 class_loader_data()->has_class_mirror_holder()) {
3243 // For a non-strong hidden class defined to an unnamed package,
3244 // its (class held) CLD will not have an unnamed module created for it.
3245 // Two choices to find the correct ModuleEntry:
3246 // 1. If hidden class is within a nest, use nest host's module
3247 // 2. Find the unnamed module off from the class loader
3248 // For now option #2 is used since a nest host is not set until
3249 // after the instance class is created in jvm_lookup_define_class().
3250 if (class_loader_data()->is_boot_class_loader_data()) {
3251 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3252 } else {
3253 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3254 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3255 return java_lang_Module::module_entry(module);
3256 }
3257 }
3258
3259 // Class is in a named package
3260 if (!in_unnamed_package()) {
3261 return _package_entry->module();
3262 }
3263
3264 // Class is in an unnamed package, return its loader's unnamed module
3265 return class_loader_data()->unnamed_module();
3266 }
3267
3268 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3269
3270 // ensure java/ packages only loaded by boot or platform builtin loaders
3271 // not needed for shared class since CDS does not archive prohibited classes.
3272 if (!is_shared()) {
3273 check_prohibited_package(name(), loader_data, CHECK);
3274 }
3275
3276 if (is_shared() && _package_entry != nullptr) {
3277 if (CDSConfig::is_loading_full_module_graph() && _package_entry == pkg_entry) {
3278 // we can use the saved package
3279 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3280 return;
3281 } else {
3282 _package_entry = nullptr;
3283 }
3284 }
3285
3286 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3287 // it returns, so we need to decrement it when the current function exits.
3288 TempNewSymbol from_class_name =
3289 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3290
3291 Symbol* pkg_name;
3292 if (pkg_entry != nullptr) {
3293 pkg_name = pkg_entry->name();
3294 } else {
3295 pkg_name = from_class_name;
3296 }
3297
3298 if (pkg_name != nullptr && loader_data != nullptr) {
3299
3300 // Find in class loader's package entry table.
3301 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3302
3303 // If the package name is not found in the loader's package
3304 // entry table, it is an indication that the package has not
3305 // been defined. Consider it defined within the unnamed module.
3306 if (_package_entry == nullptr) {
3307
3308 if (!ModuleEntryTable::javabase_defined()) {
3309 // Before java.base is defined during bootstrapping, define all packages in
3310 // the java.base module. If a non-java.base package is erroneously placed
3311 // in the java.base module it will be caught later when java.base
3312 // is defined by ModuleEntryTable::verify_javabase_packages check.
3313 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3314 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3315 } else {
3316 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3317 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3318 }
3319
3320 // A package should have been successfully created
3321 DEBUG_ONLY(ResourceMark rm(THREAD));
3322 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3323 name()->as_C_string(), loader_data->loader_name_and_id());
3324 }
3325
3326 if (log_is_enabled(Debug, module)) {
3327 ResourceMark rm(THREAD);
3328 ModuleEntry* m = _package_entry->module();
3329 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3330 external_name(),
3331 pkg_name->as_C_string(),
3332 loader_data->loader_name_and_id(),
3333 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3334 }
3335 } else {
3336 ResourceMark rm(THREAD);
3337 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3338 external_name(),
3339 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3340 UNNAMED_MODULE);
3341 }
3342 }
3343
3344 // Function set_classpath_index ensures that for a non-null _package_entry
3345 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3346 // It then sets the classpath_index in the package entry record.
3347 //
3348 // The classpath_index field is used to find the entry on the boot loader class
3349 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3350 // in an unnamed module. It is also used to indicate (for all packages whose
3351 // classes are loaded by the boot loader) that at least one of the package's
3352 // classes has been loaded.
3353 void InstanceKlass::set_classpath_index(s2 path_index) {
3354 if (_package_entry != nullptr) {
3355 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3356 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3357 assert(path_index != -1, "Unexpected classpath_index");
3358 _package_entry->set_classpath_index(path_index);
3359 }
3360 }
3361
3362 // different versions of is_same_class_package
3363
3364 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3365 oop classloader1 = this->class_loader();
3366 PackageEntry* classpkg1 = this->package();
3367 if (class2->is_objArray_klass()) {
3368 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3369 }
3370
3371 oop classloader2;
3372 PackageEntry* classpkg2;
3373 if (class2->is_instance_klass()) {
3374 classloader2 = class2->class_loader();
3375 classpkg2 = class2->package();
3376 } else {
3377 assert(class2->is_typeArray_klass(), "should be type array");
3378 classloader2 = nullptr;
3379 classpkg2 = nullptr;
3380 }
3381
3382 // Same package is determined by comparing class loader
3383 // and package entries. Both must be the same. This rule
3384 // applies even to classes that are defined in the unnamed
3385 // package, they still must have the same class loader.
3386 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3387 return true;
3388 }
3389
3390 return false;
3391 }
3392
3393 // return true if this class and other_class are in the same package. Classloader
3394 // and classname information is enough to determine a class's package
3395 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3396 const Symbol* other_class_name) const {
3397 if (class_loader() != other_class_loader) {
3398 return false;
3399 }
3400 if (name()->fast_compare(other_class_name) == 0) {
3401 return true;
3402 }
3403
3404 {
3405 ResourceMark rm;
3406
3407 bool bad_class_name = false;
3408 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3409 if (bad_class_name) {
3410 return false;
3411 }
3412 // Check that package_from_class_name() returns null, not "", if there is no package.
3413 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3414
3415 const Symbol* const this_package_name =
3416 this->package() != nullptr ? this->package()->name() : nullptr;
3417
3418 if (this_package_name == nullptr || other_pkg == nullptr) {
3419 // One of the two doesn't have a package. Only return true if the other
3420 // one also doesn't have a package.
3421 return this_package_name == other_pkg;
3422 }
3423
3424 // Check if package is identical
3425 return this_package_name->fast_compare(other_pkg) == 0;
3426 }
3427 }
3428
3429 static bool is_prohibited_package_slow(Symbol* class_name) {
3430 // Caller has ResourceMark
3431 int length;
3432 jchar* unicode = class_name->as_unicode(length);
3433 return (length >= 5 &&
3434 unicode[0] == 'j' &&
3435 unicode[1] == 'a' &&
3436 unicode[2] == 'v' &&
3437 unicode[3] == 'a' &&
3438 unicode[4] == '/');
3439 }
3440
3441 // Only boot and platform class loaders can define classes in "java/" packages.
3442 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3443 ClassLoaderData* loader_data,
3444 TRAPS) {
3445 if (!loader_data->is_boot_class_loader_data() &&
3446 !loader_data->is_platform_class_loader_data() &&
3447 class_name != nullptr && class_name->utf8_length() >= 5) {
3448 ResourceMark rm(THREAD);
3449 bool prohibited;
3450 const u1* base = class_name->base();
3451 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3452 prohibited = is_prohibited_package_slow(class_name);
3453 } else {
3454 char* name = class_name->as_C_string();
3455 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3456 }
3457 if (prohibited) {
3458 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3459 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3460 char* name = pkg_name->as_C_string();
3461 const char* class_loader_name = loader_data->loader_name_and_id();
3462 StringUtils::replace_no_expand(name, "/", ".");
3463 const char* msg_text1 = "Class loader (instance of): ";
3464 const char* msg_text2 = " tried to load prohibited package name: ";
3465 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3466 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3467 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3468 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3469 }
3470 }
3471 return;
3472 }
3473
3474 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3475 constantPoolHandle i_cp(THREAD, constants());
3476 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3477 int ioff = iter.inner_class_info_index();
3478 if (ioff != 0) {
3479 // Check to see if the name matches the class we're looking for
3480 // before attempting to find the class.
3481 if (i_cp->klass_name_at_matches(this, ioff)) {
3482 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3483 if (this == inner_klass) {
3484 *ooff = iter.outer_class_info_index();
3485 *noff = iter.inner_name_index();
3486 return true;
3487 }
3488 }
3489 }
3490 }
3491 return false;
3492 }
3493
3494 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3495 InstanceKlass* outer_klass = nullptr;
3496 *inner_is_member = false;
3497 int ooff = 0, noff = 0;
3498 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3499 if (has_inner_classes_attr) {
3500 constantPoolHandle i_cp(THREAD, constants());
3501 if (ooff != 0) {
3502 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3503 if (!ok->is_instance_klass()) {
3504 // If the outer class is not an instance klass then it cannot have
3505 // declared any inner classes.
3506 ResourceMark rm(THREAD);
3507 Exceptions::fthrow(
3508 THREAD_AND_LOCATION,
3509 vmSymbols::java_lang_IncompatibleClassChangeError(),
3510 "%s and %s disagree on InnerClasses attribute",
3511 ok->external_name(),
3512 external_name());
3513 return nullptr;
3514 }
3515 outer_klass = InstanceKlass::cast(ok);
3516 *inner_is_member = true;
3517 }
3518 if (nullptr == outer_klass) {
3519 // It may be a local class; try for that.
3520 int encl_method_class_idx = enclosing_method_class_index();
3521 if (encl_method_class_idx != 0) {
3522 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3523 outer_klass = InstanceKlass::cast(ok);
3524 *inner_is_member = false;
3525 }
3526 }
3527 }
3528
3529 // If no inner class attribute found for this class.
3530 if (nullptr == outer_klass) return nullptr;
3531
3532 // Throws an exception if outer klass has not declared k as an inner klass
3533 // We need evidence that each klass knows about the other, or else
3534 // the system could allow a spoof of an inner class to gain access rights.
3535 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3536 return outer_klass;
3537 }
3538
3539 jint InstanceKlass::compute_modifier_flags() const {
3540 jint access = access_flags().as_int();
3541
3542 // But check if it happens to be member class.
3543 InnerClassesIterator iter(this);
3544 for (; !iter.done(); iter.next()) {
3545 int ioff = iter.inner_class_info_index();
3546 // Inner class attribute can be zero, skip it.
3547 // Strange but true: JVM spec. allows null inner class refs.
3548 if (ioff == 0) continue;
3549
3550 // only look at classes that are already loaded
3551 // since we are looking for the flags for our self.
3552 Symbol* inner_name = constants()->klass_name_at(ioff);
3553 if (name() == inner_name) {
3554 // This is really a member class.
3555 access = iter.inner_access_flags();
3556 break;
3557 }
3558 }
3559 return (access & JVM_ACC_WRITTEN_FLAGS);
3560 }
3561
3562 jint InstanceKlass::jvmti_class_status() const {
3563 jint result = 0;
3564
3565 if (is_linked()) {
3566 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3567 }
3568
3569 if (is_initialized()) {
3570 assert(is_linked(), "Class status is not consistent");
3571 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3572 }
3573 if (is_in_error_state()) {
3574 result |= JVMTI_CLASS_STATUS_ERROR;
3575 }
3576 return result;
3577 }
3578
3579 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3580 bool implements_interface; // initialized by method_at_itable_or_null
3581 Method* m = method_at_itable_or_null(holder, index,
3582 implements_interface); // out parameter
3583 if (m != nullptr) {
3584 assert(implements_interface, "sanity");
3585 return m;
3586 } else if (implements_interface) {
3587 // Throw AbstractMethodError since corresponding itable slot is empty.
3588 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3589 } else {
3590 // If the interface isn't implemented by the receiver class,
3591 // the VM should throw IncompatibleClassChangeError.
3592 ResourceMark rm(THREAD);
3593 stringStream ss;
3594 bool same_module = (module() == holder->module());
3595 ss.print("Receiver class %s does not implement "
3596 "the interface %s defining the method to be called "
3597 "(%s%s%s)",
3598 external_name(), holder->external_name(),
3599 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3600 (same_module) ? "" : "; ",
3601 (same_module) ? "" : holder->class_in_module_of_loader());
3602 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3603 }
3604 }
3605
3606 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3607 klassItable itable(this);
3608 for (int i = 0; i < itable.size_offset_table(); i++) {
3609 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3610 if (offset_entry->interface_klass() == holder) {
3611 implements_interface = true;
3612 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3613 Method* m = ime[index].method();
3614 return m;
3615 }
3616 }
3617 implements_interface = false;
3618 return nullptr; // offset entry not found
3619 }
3620
3621 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3622 assert(is_linked(), "required");
3623 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3624 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3625
3626 int vtable_index = Method::invalid_vtable_index;
3627 Symbol* name = intf_method->name();
3628 Symbol* signature = intf_method->signature();
3629
3630 // First check in default method array
3631 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3632 int index = find_method_index(default_methods(),
3633 name, signature,
3634 Klass::OverpassLookupMode::find,
3635 Klass::StaticLookupMode::find,
3636 Klass::PrivateLookupMode::find);
3637 if (index >= 0) {
3638 vtable_index = default_vtable_indices()->at(index);
3639 }
3640 }
3641 if (vtable_index == Method::invalid_vtable_index) {
3642 // get vtable_index for miranda methods
3643 klassVtable vt = vtable();
3644 vtable_index = vt.index_of_miranda(name, signature);
3645 }
3646 return vtable_index;
3647 }
3648
3649 #if INCLUDE_JVMTI
3650 // update default_methods for redefineclasses for methods that are
3651 // not yet in the vtable due to concurrent subclass define and superinterface
3652 // redefinition
3653 // Note: those in the vtable, should have been updated via adjust_method_entries
3654 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3655 // search the default_methods for uses of either obsolete or EMCP methods
3656 if (default_methods() != nullptr) {
3657 for (int index = 0; index < default_methods()->length(); index ++) {
3658 Method* old_method = default_methods()->at(index);
3659 if (old_method == nullptr || !old_method->is_old()) {
3660 continue; // skip uninteresting entries
3661 }
3662 assert(!old_method->is_deleted(), "default methods may not be deleted");
3663 Method* new_method = old_method->get_new_method();
3664 default_methods()->at_put(index, new_method);
3665
3666 if (log_is_enabled(Info, redefine, class, update)) {
3667 ResourceMark rm;
3668 if (!(*trace_name_printed)) {
3669 log_info(redefine, class, update)
3670 ("adjust: klassname=%s default methods from name=%s",
3671 external_name(), old_method->method_holder()->external_name());
3672 *trace_name_printed = true;
3673 }
3674 log_debug(redefine, class, update, vtables)
3675 ("default method update: %s(%s) ",
3676 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3677 }
3678 }
3679 }
3680 }
3681 #endif // INCLUDE_JVMTI
3682
3683 // On-stack replacement stuff
3684 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3685 assert_lock_strong(CompiledMethod_lock);
3686 #ifndef PRODUCT
3687 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3688 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3689 "redundant OSR recompilation detected. memory leak in CodeCache!");
3690 #endif
3691 // only one compilation can be active
3692 assert(n->is_osr_method(), "wrong kind of nmethod");
3693 n->set_osr_link(osr_nmethods_head());
3694 set_osr_nmethods_head(n);
3695 // Raise the highest osr level if necessary
3696 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3697
3698 // Get rid of the osr methods for the same bci that have lower levels.
3699 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3700 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3701 if (inv != nullptr && inv->is_in_use()) {
3702 inv->make_not_entrant();
3703 }
3704 }
3705 }
3706
3707 // Remove osr nmethod from the list. Return true if found and removed.
3708 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3709 // This is a short non-blocking critical region, so the no safepoint check is ok.
3710 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3711 assert(n->is_osr_method(), "wrong kind of nmethod");
3712 nmethod* last = nullptr;
3713 nmethod* cur = osr_nmethods_head();
3714 int max_level = CompLevel_none; // Find the max comp level excluding n
3715 Method* m = n->method();
3716 // Search for match
3717 bool found = false;
3718 while(cur != nullptr && cur != n) {
3719 if (m == cur->method()) {
3720 // Find max level before n
3721 max_level = MAX2(max_level, cur->comp_level());
3722 }
3723 last = cur;
3724 cur = cur->osr_link();
3725 }
3726 nmethod* next = nullptr;
3727 if (cur == n) {
3728 found = true;
3729 next = cur->osr_link();
3730 if (last == nullptr) {
3731 // Remove first element
3732 set_osr_nmethods_head(next);
3733 } else {
3734 last->set_osr_link(next);
3735 }
3736 }
3737 n->set_osr_link(nullptr);
3738 cur = next;
3739 while (cur != nullptr) {
3740 // Find max level after n
3741 if (m == cur->method()) {
3742 max_level = MAX2(max_level, cur->comp_level());
3743 }
3744 cur = cur->osr_link();
3745 }
3746 m->set_highest_osr_comp_level(max_level);
3747 return found;
3748 }
3749
3750 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3751 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3752 nmethod* osr = osr_nmethods_head();
3753 int found = 0;
3754 while (osr != nullptr) {
3755 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3756 if (osr->method() == m) {
3757 deopt_scope->mark(osr);
3758 found++;
3759 }
3760 osr = osr->osr_link();
3761 }
3762 return found;
3763 }
3764
3765 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3766 ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3767 nmethod* osr = osr_nmethods_head();
3768 nmethod* best = nullptr;
3769 while (osr != nullptr) {
3770 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3771 // There can be a time when a c1 osr method exists but we are waiting
3772 // for a c2 version. When c2 completes its osr nmethod we will trash
3773 // the c1 version and only be able to find the c2 version. However
3774 // while we overflow in the c1 code at back branches we don't want to
3775 // try and switch to the same code as we are already running
3776
3777 if (osr->method() == m &&
3778 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3779 if (match_level) {
3780 if (osr->comp_level() == comp_level) {
3781 // Found a match - return it.
3782 return osr;
3783 }
3784 } else {
3785 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3786 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3787 // Found the best possible - return it.
3788 return osr;
3789 }
3790 best = osr;
3791 }
3792 }
3793 }
3794 osr = osr->osr_link();
3795 }
3796
3797 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3798 if (best != nullptr && best->comp_level() >= comp_level) {
3799 return best;
3800 }
3801 return nullptr;
3802 }
3803
3804 // -----------------------------------------------------------------------------------------------------
3805 // Printing
3806
3807 #define BULLET " - "
3808
3809 static const char* state_names[] = {
3810 "allocated", "loaded", "being_linked", "linked", "being_initialized", "fully_initialized", "initialization_error"
3811 };
3812
3813 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3814 ResourceMark rm;
3815 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3816 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3817 for (int i = 0; i < len; i++) {
3818 intptr_t e = start[i];
3819 st->print("%d : " INTPTR_FORMAT, i, e);
3820 if (forward_refs[i] != 0) {
3821 int from = forward_refs[i];
3822 int off = (int) start[from];
3823 st->print(" (offset %d <= [%d])", off, from);
3824 }
3825 if (MetaspaceObj::is_valid((Metadata*)e)) {
3826 st->print(" ");
3827 ((Metadata*)e)->print_value_on(st);
3828 } else if (self != nullptr && e > 0 && e < 0x10000) {
3829 address location = self + e;
3830 int index = (int)((intptr_t*)location - start);
3831 st->print(" (offset %d => [%d])", (int)e, index);
3832 if (index >= 0 && index < len)
3833 forward_refs[index] = i;
3834 }
3835 st->cr();
3836 }
3837 }
3838
3839 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3840 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3841 }
3842
3843 template<typename T>
3844 static void print_array_on(outputStream* st, Array<T>* array) {
3845 if (array == nullptr) { st->print_cr("nullptr"); return; }
3846 array->print_value_on(st); st->cr();
3847 if (Verbose || WizardMode) {
3848 for (int i = 0; i < array->length(); i++) {
3849 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3850 }
3851 }
3852 }
3853
3854 static void print_array_on(outputStream* st, Array<int>* array) {
3855 if (array == nullptr) { st->print_cr("nullptr"); return; }
3856 array->print_value_on(st); st->cr();
3857 if (Verbose || WizardMode) {
3858 for (int i = 0; i < array->length(); i++) {
3859 st->print("%d : %d", i, array->at(i)); st->cr();
3860 }
3861 }
3862 }
3863
3864 const char* InstanceKlass::init_state_name() const {
3865 return state_names[init_state()];
3866 }
3867
3868 void InstanceKlass::print_on(outputStream* st) const {
3869 assert(is_klass(), "must be klass");
3870 Klass::print_on(st);
3871
3872 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3873 st->print(BULLET"klass size: %d", size()); st->cr();
3874 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3875 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3876 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3877 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3878 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3879 st->print(BULLET"sub: ");
3880 Klass* sub = subklass();
3881 int n;
3882 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3883 if (n < MaxSubklassPrintSize) {
3884 sub->print_value_on(st);
3885 st->print(" ");
3886 }
3887 }
3888 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3889 st->cr();
3890
3891 if (is_interface()) {
3892 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3893 if (nof_implementors() == 1) {
3894 st->print_cr(BULLET"implementor: ");
3895 st->print(" ");
3896 implementor()->print_value_on(st);
3897 st->cr();
3898 }
3899 }
3900
3901 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3902 st->print(BULLET"methods: "); print_array_on(st, methods());
3903 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3904 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3905 if (default_vtable_indices() != nullptr) {
3906 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3907 }
3908 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3909 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3910 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3911 if (class_loader_data() != nullptr) {
3912 st->print(BULLET"class loader data: ");
3913 class_loader_data()->print_value_on(st);
3914 st->cr();
3915 }
3916 if (source_file_name() != nullptr) {
3917 st->print(BULLET"source file: ");
3918 source_file_name()->print_value_on(st);
3919 st->cr();
3920 }
3921 if (source_debug_extension() != nullptr) {
3922 st->print(BULLET"source debug extension: ");
3923 st->print("%s", source_debug_extension());
3924 st->cr();
3925 }
3926 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3927 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3928 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3929 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3930 {
3931 bool have_pv = false;
3932 // previous versions are linked together through the InstanceKlass
3933 for (InstanceKlass* pv_node = previous_versions();
3934 pv_node != nullptr;
3935 pv_node = pv_node->previous_versions()) {
3936 if (!have_pv)
3937 st->print(BULLET"previous version: ");
3938 have_pv = true;
3939 pv_node->constants()->print_value_on(st);
3940 }
3941 if (have_pv) st->cr();
3942 }
3943
3944 if (generic_signature() != nullptr) {
3945 st->print(BULLET"generic signature: ");
3946 generic_signature()->print_value_on(st);
3947 st->cr();
3948 }
3949 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3950 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3951 if (record_components() != nullptr) {
3952 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3953 }
3954 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3955 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
3956 if (java_mirror() != nullptr) {
3957 st->print(BULLET"java mirror: ");
3958 java_mirror()->print_value_on(st);
3959 st->cr();
3960 } else {
3961 st->print_cr(BULLET"java mirror: null");
3962 }
3963 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3964 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3965 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3966 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3967 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3968 FieldPrinter print_static_field(st);
3969 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3970 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3971 FieldPrinter print_nonstatic_field(st);
3972 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3973 ik->print_nonstatic_fields(&print_nonstatic_field);
3974
3975 st->print(BULLET"non-static oop maps: ");
3976 OopMapBlock* map = start_of_nonstatic_oop_maps();
3977 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3978 while (map < end_map) {
3979 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3980 map++;
3981 }
3982 st->cr();
3983 }
3984
3985 void InstanceKlass::print_value_on(outputStream* st) const {
3986 assert(is_klass(), "must be klass");
3987 if (Verbose || WizardMode) access_flags().print_on(st);
3988 name()->print_value_on(st);
3989 }
3990
3991 void FieldPrinter::do_field(fieldDescriptor* fd) {
3992 _st->print(BULLET);
3993 if (_obj == nullptr) {
3994 fd->print_on(_st);
3995 _st->cr();
3996 } else {
3997 fd->print_on_for(_st, _obj);
3998 _st->cr();
3999 }
4000 }
4001
4002
4003 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
4004 Klass::oop_print_on(obj, st);
4005
4006 if (this == vmClasses::String_klass()) {
4007 typeArrayOop value = java_lang_String::value(obj);
4008 juint length = java_lang_String::length(obj);
4009 if (value != nullptr &&
4010 value->is_typeArray() &&
4011 length <= (juint) value->length()) {
4012 st->print(BULLET"string: ");
4013 java_lang_String::print(obj, st);
4014 st->cr();
4015 }
4016 }
4017
4018 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
4019 FieldPrinter print_field(st, obj);
4020 print_nonstatic_fields(&print_field);
4021
4022 if (this == vmClasses::Class_klass()) {
4023 st->print(BULLET"signature: ");
4024 java_lang_Class::print_signature(obj, st);
4025 st->cr();
4026 Klass* real_klass = java_lang_Class::as_Klass(obj);
4027 if (real_klass != nullptr && real_klass->is_instance_klass()) {
4028 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
4029 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
4030 }
4031 } else if (this == vmClasses::MethodType_klass()) {
4032 st->print(BULLET"signature: ");
4033 java_lang_invoke_MethodType::print_signature(obj, st);
4034 st->cr();
4035 }
4036 }
4037
4038 #ifndef PRODUCT
4039
4040 bool InstanceKlass::verify_itable_index(int i) {
4041 int method_count = klassItable::method_count_for_interface(this);
4042 assert(i >= 0 && i < method_count, "index out of bounds");
4043 return true;
4044 }
4045
4046 #endif //PRODUCT
4047
4048 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
4049 st->print("a ");
4050 name()->print_value_on(st);
4051 obj->print_address_on(st);
4052 if (this == vmClasses::String_klass()
4053 && java_lang_String::value(obj) != nullptr) {
4054 ResourceMark rm;
4055 int len = java_lang_String::length(obj);
4056 int plen = (len < 24 ? len : 12);
4057 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
4058 st->print(" = \"%s\"", str);
4059 if (len > plen)
4060 st->print("...[%d]", len);
4061 } else if (this == vmClasses::Class_klass()) {
4062 Klass* k = java_lang_Class::as_Klass(obj);
4063 st->print(" = ");
4064 if (k != nullptr) {
4065 k->print_value_on(st);
4066 } else {
4067 const char* tname = type2name(java_lang_Class::primitive_type(obj));
4068 st->print("%s", tname ? tname : "type?");
4069 }
4070 } else if (this == vmClasses::MethodType_klass()) {
4071 st->print(" = ");
4072 java_lang_invoke_MethodType::print_signature(obj, st);
4073 } else if (java_lang_boxing_object::is_instance(obj)) {
4074 st->print(" = ");
4075 java_lang_boxing_object::print(obj, st);
4076 } else if (this == vmClasses::LambdaForm_klass()) {
4077 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4078 if (vmentry != nullptr) {
4079 st->print(" => ");
4080 vmentry->print_value_on(st);
4081 }
4082 } else if (this == vmClasses::MemberName_klass()) {
4083 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4084 if (vmtarget != nullptr) {
4085 st->print(" = ");
4086 vmtarget->print_value_on(st);
4087 } else {
4088 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4089 oop name = java_lang_invoke_MemberName::name(obj);
4090 if (clazz != nullptr) {
4091 clazz->print_value_on(st);
4092 } else {
4093 st->print("null");
4094 }
4095 st->print(".");
4096 if (name != nullptr) {
4097 name->print_value_on(st);
4098 } else {
4099 st->print("null");
4100 }
4101 }
4102 }
4103 }
4104
4105 const char* InstanceKlass::internal_name() const {
4106 return external_name();
4107 }
4108
4109 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4110 const ModuleEntry* module_entry,
4111 const ClassFileStream* cfs) const {
4112
4113 if (ClassListWriter::is_enabled()) {
4114 ClassListWriter::write(this, cfs);
4115 }
4116
4117 print_class_load_helper(loader_data, module_entry, cfs);
4118 print_class_load_cause_logging();
4119 }
4120
4121 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4122 const ModuleEntry* module_entry,
4123 const ClassFileStream* cfs) const {
4124
4125 if (!log_is_enabled(Info, class, load)) {
4126 return;
4127 }
4128
4129 ResourceMark rm;
4130 LogMessage(class, load) msg;
4131 stringStream info_stream;
4132
4133 // Name and class hierarchy info
4134 info_stream.print("%s", external_name());
4135
4136 // Source
4137 if (cfs != nullptr) {
4138 if (cfs->source() != nullptr) {
4139 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4140 if (module_name != nullptr) {
4141 // When the boot loader created the stream, it didn't know the module name
4142 // yet. Let's format it now.
4143 if (cfs->from_boot_loader_modules_image()) {
4144 info_stream.print(" source: jrt:/%s", module_name);
4145 } else {
4146 info_stream.print(" source: %s", cfs->source());
4147 }
4148 } else {
4149 info_stream.print(" source: %s", cfs->source());
4150 }
4151 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4152 Thread* current = Thread::current();
4153 Klass* caller = current->is_Java_thread() ?
4154 JavaThread::cast(current)->security_get_caller_class(1):
4155 nullptr;
4156 // caller can be null, for example, during a JVMTI VM_Init hook
4157 if (caller != nullptr) {
4158 info_stream.print(" source: instance of %s", caller->external_name());
4159 } else {
4160 // source is unknown
4161 }
4162 } else {
4163 oop class_loader = loader_data->class_loader();
4164 info_stream.print(" source: %s", class_loader->klass()->external_name());
4165 }
4166 } else {
4167 assert(this->is_shared(), "must be");
4168 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4169 info_stream.print(" source: shared objects file (top)");
4170 } else {
4171 info_stream.print(" source: shared objects file");
4172 }
4173 }
4174
4175 msg.info("%s", info_stream.as_string());
4176
4177 if (log_is_enabled(Debug, class, load)) {
4178 stringStream debug_stream;
4179
4180 // Class hierarchy info
4181 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4182 p2i(this), p2i(superklass()));
4183
4184 // Interfaces
4185 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4186 debug_stream.print(" interfaces:");
4187 int length = local_interfaces()->length();
4188 for (int i = 0; i < length; i++) {
4189 debug_stream.print(" " PTR_FORMAT,
4190 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4191 }
4192 }
4193
4194 // Class loader
4195 debug_stream.print(" loader: [");
4196 loader_data->print_value_on(&debug_stream);
4197 debug_stream.print("]");
4198
4199 // Classfile checksum
4200 if (cfs) {
4201 debug_stream.print(" bytes: %d checksum: %08x",
4202 cfs->length(),
4203 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4204 cfs->length()));
4205 }
4206
4207 msg.debug("%s", debug_stream.as_string());
4208 }
4209 }
4210
4211 void InstanceKlass::print_class_load_cause_logging() const {
4212 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4213 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4214 JavaThread* current = JavaThread::current();
4215 ResourceMark rm(current);
4216 const char* name = external_name();
4217
4218 if (LogClassLoadingCauseFor == nullptr ||
4219 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4220 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4221 return;
4222 }
4223
4224 // Log Java stack first
4225 {
4226 LogMessage(class, load, cause) msg;
4227 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4228
4229 info_stream.print_cr("Java stack when loading %s:", name);
4230 current->print_stack_on(&info_stream);
4231 }
4232
4233 // Log native stack second
4234 if (log_cause_native) {
4235 // Log to string first so that lines can be indented
4236 stringStream stack_stream;
4237 char buf[O_BUFLEN];
4238 address lastpc = nullptr;
4239 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4240 // We have printed the native stack in platform-specific code,
4241 // so nothing else to do in this case.
4242 } else {
4243 frame f = os::current_frame();
4244 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4245 -1 /* max stack_stream */, buf, O_BUFLEN);
4246 }
4247
4248 LogMessage(class, load, cause, native) msg;
4249 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4250 info_stream.print_cr("Native stack when loading %s:", name);
4251
4252 // Print each native stack line to the log
4253 int size = (int) stack_stream.size();
4254 char* stack = stack_stream.as_string();
4255 char* stack_end = stack + size;
4256 char* line_start = stack;
4257 for (char* p = stack; p < stack_end; p++) {
4258 if (*p == '\n') {
4259 *p = '\0';
4260 info_stream.print_cr("\t%s", line_start);
4261 line_start = p + 1;
4262 }
4263 }
4264 if (line_start < stack_end) {
4265 info_stream.print_cr("\t%s", line_start);
4266 }
4267 }
4268 }
4269 }
4270
4271 // Verification
4272
4273 class VerifyFieldClosure: public BasicOopIterateClosure {
4274 protected:
4275 template <class T> void do_oop_work(T* p) {
4276 oop obj = RawAccess<>::oop_load(p);
4277 if (!oopDesc::is_oop_or_null(obj)) {
4278 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4279 Universe::print_on(tty);
4280 guarantee(false, "boom");
4281 }
4282 }
4283 public:
4284 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4285 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4286 };
4287
4288 void InstanceKlass::verify_on(outputStream* st) {
4289 #ifndef PRODUCT
4290 // Avoid redundant verifies, this really should be in product.
4291 if (_verify_count == Universe::verify_count()) return;
4292 _verify_count = Universe::verify_count();
4293 #endif
4294
4295 // Verify Klass
4296 Klass::verify_on(st);
4297
4298 // Verify that klass is present in ClassLoaderData
4299 guarantee(class_loader_data()->contains_klass(this),
4300 "this class isn't found in class loader data");
4301
4302 // Verify vtables
4303 if (is_linked()) {
4304 // $$$ This used to be done only for m/s collections. Doing it
4305 // always seemed a valid generalization. (DLD -- 6/00)
4306 vtable().verify(st);
4307 }
4308
4309 // Verify first subklass
4310 if (subklass() != nullptr) {
4311 guarantee(subklass()->is_klass(), "should be klass");
4312 }
4313
4314 // Verify siblings
4315 Klass* super = this->super();
4316 Klass* sib = next_sibling();
4317 if (sib != nullptr) {
4318 if (sib == this) {
4319 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4320 }
4321
4322 guarantee(sib->is_klass(), "should be klass");
4323 guarantee(sib->super() == super, "siblings should have same superklass");
4324 }
4325
4326 // Verify local interfaces
4327 if (local_interfaces()) {
4328 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4329 for (int j = 0; j < local_interfaces->length(); j++) {
4330 InstanceKlass* e = local_interfaces->at(j);
4331 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4332 }
4333 }
4334
4335 // Verify transitive interfaces
4336 if (transitive_interfaces() != nullptr) {
4337 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4338 for (int j = 0; j < transitive_interfaces->length(); j++) {
4339 InstanceKlass* e = transitive_interfaces->at(j);
4340 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4341 }
4342 }
4343
4344 // Verify methods
4345 if (methods() != nullptr) {
4346 Array<Method*>* methods = this->methods();
4347 for (int j = 0; j < methods->length(); j++) {
4348 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4349 }
4350 for (int j = 0; j < methods->length() - 1; j++) {
4351 Method* m1 = methods->at(j);
4352 Method* m2 = methods->at(j + 1);
4353 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4354 }
4355 }
4356
4357 // Verify method ordering
4358 if (method_ordering() != nullptr) {
4359 Array<int>* method_ordering = this->method_ordering();
4360 int length = method_ordering->length();
4361 if (JvmtiExport::can_maintain_original_method_order() ||
4362 ((UseSharedSpaces || CDSConfig::is_dumping_archive()) && length != 0)) {
4363 guarantee(length == methods()->length(), "invalid method ordering length");
4364 jlong sum = 0;
4365 for (int j = 0; j < length; j++) {
4366 int original_index = method_ordering->at(j);
4367 guarantee(original_index >= 0, "invalid method ordering index");
4368 guarantee(original_index < length, "invalid method ordering index");
4369 sum += original_index;
4370 }
4371 // Verify sum of indices 0,1,...,length-1
4372 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4373 } else {
4374 guarantee(length == 0, "invalid method ordering length");
4375 }
4376 }
4377
4378 // Verify default methods
4379 if (default_methods() != nullptr) {
4380 Array<Method*>* methods = this->default_methods();
4381 for (int j = 0; j < methods->length(); j++) {
4382 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4383 }
4384 for (int j = 0; j < methods->length() - 1; j++) {
4385 Method* m1 = methods->at(j);
4386 Method* m2 = methods->at(j + 1);
4387 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4388 }
4389 }
4390
4391 // Verify JNI static field identifiers
4392 if (jni_ids() != nullptr) {
4393 jni_ids()->verify(this);
4394 }
4395
4396 // Verify other fields
4397 if (constants() != nullptr) {
4398 guarantee(constants()->is_constantPool(), "should be constant pool");
4399 }
4400 }
4401
4402 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4403 Klass::oop_verify_on(obj, st);
4404 VerifyFieldClosure blk;
4405 obj->oop_iterate(&blk);
4406 }
4407
4408
4409 // JNIid class for jfieldIDs only
4410 // Note to reviewers:
4411 // These JNI functions are just moved over to column 1 and not changed
4412 // in the compressed oops workspace.
4413 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4414 _holder = holder;
4415 _offset = offset;
4416 _next = next;
4417 debug_only(_is_static_field_id = false;)
4418 }
4419
4420
4421 JNIid* JNIid::find(int offset) {
4422 JNIid* current = this;
4423 while (current != nullptr) {
4424 if (current->offset() == offset) return current;
4425 current = current->next();
4426 }
4427 return nullptr;
4428 }
4429
4430 void JNIid::deallocate(JNIid* current) {
4431 while (current != nullptr) {
4432 JNIid* next = current->next();
4433 delete current;
4434 current = next;
4435 }
4436 }
4437
4438
4439 void JNIid::verify(Klass* holder) {
4440 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4441 int end_field_offset;
4442 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4443
4444 JNIid* current = this;
4445 while (current != nullptr) {
4446 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4447 #ifdef ASSERT
4448 int o = current->offset();
4449 if (current->is_static_field_id()) {
4450 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4451 }
4452 #endif
4453 current = current->next();
4454 }
4455 }
4456
4457 void InstanceKlass::set_init_state(ClassState state) {
4458 if (state > loaded) {
4459 assert_lock_strong(_init_monitor);
4460 }
4461 #ifdef ASSERT
4462 bool good_state = is_shared() ? (_init_state <= state)
4463 : (_init_state < state);
4464 bool link_failed = _init_state == being_linked && state == loaded;
4465 assert(good_state || state == allocated || link_failed, "illegal state transition");
4466 #endif
4467 assert(_init_thread == nullptr, "should be cleared before state change");
4468 Atomic::store(&_init_state, state);
4469 }
4470
4471 #if INCLUDE_JVMTI
4472
4473 // RedefineClasses() support for previous versions
4474
4475 // Globally, there is at least one previous version of a class to walk
4476 // during class unloading, which is saved because old methods in the class
4477 // are still running. Otherwise the previous version list is cleaned up.
4478 bool InstanceKlass::_should_clean_previous_versions = false;
4479
4480 // Returns true if there are previous versions of a class for class
4481 // unloading only. Also resets the flag to false. purge_previous_version
4482 // will set the flag to true if there are any left, i.e., if there's any
4483 // work to do for next time. This is to avoid the expensive code cache
4484 // walk in CLDG::clean_deallocate_lists().
4485 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4486 bool ret = _should_clean_previous_versions;
4487 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4488 ret ? "true" : "false");
4489 _should_clean_previous_versions = false;
4490 return ret;
4491 }
4492
4493 // This nulls out jmethodIDs for all methods in 'klass'
4494 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4495 // during class unloading.
4496 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4497 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4498 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4499 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4500 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4501 Array<Method*>* method_refs = klass->methods();
4502 for (int k = 0; k < method_refs->length(); k++) {
4503 Method* method = method_refs->at(k);
4504 if (method != nullptr && method->is_obsolete()) {
4505 method->clear_jmethod_id();
4506 }
4507 }
4508 }
4509
4510 // Purge previous versions before adding new previous versions of the class and
4511 // during class unloading.
4512 void InstanceKlass::purge_previous_version_list() {
4513 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4514 assert(has_been_redefined(), "Should only be called for main class");
4515
4516 // Quick exit.
4517 if (previous_versions() == nullptr) {
4518 return;
4519 }
4520
4521 // This klass has previous versions so see what we can cleanup
4522 // while it is safe to do so.
4523
4524 int deleted_count = 0; // leave debugging breadcrumbs
4525 int live_count = 0;
4526 ClassLoaderData* loader_data = class_loader_data();
4527 assert(loader_data != nullptr, "should never be null");
4528
4529 ResourceMark rm;
4530 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4531
4532 // previous versions are linked together through the InstanceKlass
4533 InstanceKlass* pv_node = previous_versions();
4534 InstanceKlass* last = this;
4535 int version = 0;
4536
4537 // check the previous versions list
4538 for (; pv_node != nullptr; ) {
4539
4540 ConstantPool* pvcp = pv_node->constants();
4541 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4542
4543 if (!pvcp->on_stack()) {
4544 // If the constant pool isn't on stack, none of the methods
4545 // are executing. Unlink this previous_version.
4546 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4547 // so will be deallocated during the next phase of class unloading.
4548 log_trace(redefine, class, iklass, purge)
4549 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4550 // Unlink from previous version list.
4551 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4552 InstanceKlass* next = pv_node->previous_versions();
4553 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4554 pv_node->link_previous_versions(nullptr); // point next to null
4555 last->link_previous_versions(next);
4556 // Delete this node directly. Nothing is referring to it and we don't
4557 // want it to increase the counter for metadata to delete in CLDG.
4558 MetadataFactory::free_metadata(loader_data, pv_node);
4559 pv_node = next;
4560 deleted_count++;
4561 version++;
4562 continue;
4563 } else {
4564 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4565 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4566 live_count++;
4567 if (pvcp->is_shared()) {
4568 // Shared previous versions can never be removed so no cleaning is needed.
4569 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4570 } else {
4571 // Previous version alive, set that clean is needed for next time.
4572 _should_clean_previous_versions = true;
4573 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4574 }
4575 }
4576
4577 // next previous version
4578 last = pv_node;
4579 pv_node = pv_node->previous_versions();
4580 version++;
4581 }
4582 log_trace(redefine, class, iklass, purge)
4583 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4584 }
4585
4586 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4587 int emcp_method_count) {
4588 int obsolete_method_count = old_methods->length() - emcp_method_count;
4589
4590 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4591 _previous_versions != nullptr) {
4592 // We have a mix of obsolete and EMCP methods so we have to
4593 // clear out any matching EMCP method entries the hard way.
4594 int local_count = 0;
4595 for (int i = 0; i < old_methods->length(); i++) {
4596 Method* old_method = old_methods->at(i);
4597 if (old_method->is_obsolete()) {
4598 // only obsolete methods are interesting
4599 Symbol* m_name = old_method->name();
4600 Symbol* m_signature = old_method->signature();
4601
4602 // previous versions are linked together through the InstanceKlass
4603 int j = 0;
4604 for (InstanceKlass* prev_version = _previous_versions;
4605 prev_version != nullptr;
4606 prev_version = prev_version->previous_versions(), j++) {
4607
4608 Array<Method*>* method_refs = prev_version->methods();
4609 for (int k = 0; k < method_refs->length(); k++) {
4610 Method* method = method_refs->at(k);
4611
4612 if (!method->is_obsolete() &&
4613 method->name() == m_name &&
4614 method->signature() == m_signature) {
4615 // The current RedefineClasses() call has made all EMCP
4616 // versions of this method obsolete so mark it as obsolete
4617 log_trace(redefine, class, iklass, add)
4618 ("%s(%s): flush obsolete method @%d in version @%d",
4619 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4620
4621 method->set_is_obsolete();
4622 break;
4623 }
4624 }
4625
4626 // The previous loop may not find a matching EMCP method, but
4627 // that doesn't mean that we can optimize and not go any
4628 // further back in the PreviousVersion generations. The EMCP
4629 // method for this generation could have already been made obsolete,
4630 // but there still may be an older EMCP method that has not
4631 // been made obsolete.
4632 }
4633
4634 if (++local_count >= obsolete_method_count) {
4635 // no more obsolete methods so bail out now
4636 break;
4637 }
4638 }
4639 }
4640 }
4641 }
4642
4643 // Save the scratch_class as the previous version if any of the methods are running.
4644 // The previous_versions are used to set breakpoints in EMCP methods and they are
4645 // also used to clean MethodData links to redefined methods that are no longer running.
4646 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4647 int emcp_method_count) {
4648 assert(Thread::current()->is_VM_thread(),
4649 "only VMThread can add previous versions");
4650
4651 ResourceMark rm;
4652 log_trace(redefine, class, iklass, add)
4653 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4654
4655 // Clean out old previous versions for this class
4656 purge_previous_version_list();
4657
4658 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4659 // a previous redefinition may be made obsolete by this redefinition.
4660 Array<Method*>* old_methods = scratch_class->methods();
4661 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4662
4663 // If the constant pool for this previous version of the class
4664 // is not marked as being on the stack, then none of the methods
4665 // in this previous version of the class are on the stack so
4666 // we don't need to add this as a previous version.
4667 ConstantPool* cp_ref = scratch_class->constants();
4668 if (!cp_ref->on_stack()) {
4669 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4670 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4671 return;
4672 }
4673
4674 // Add previous version if any methods are still running or if this is
4675 // a shared class which should never be removed.
4676 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4677 scratch_class->link_previous_versions(previous_versions());
4678 link_previous_versions(scratch_class);
4679 if (cp_ref->is_shared()) {
4680 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4681 } else {
4682 // We only set clean_previous_versions flag for processing during class
4683 // unloading for non-shared classes.
4684 _should_clean_previous_versions = true;
4685 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4686 }
4687 } // end add_previous_version()
4688
4689 #endif // INCLUDE_JVMTI
4690
4691 Method* InstanceKlass::method_with_idnum(int idnum) {
4692 Method* m = nullptr;
4693 if (idnum < methods()->length()) {
4694 m = methods()->at(idnum);
4695 }
4696 if (m == nullptr || m->method_idnum() != idnum) {
4697 for (int index = 0; index < methods()->length(); ++index) {
4698 m = methods()->at(index);
4699 if (m->method_idnum() == idnum) {
4700 return m;
4701 }
4702 }
4703 // None found, return null for the caller to handle.
4704 return nullptr;
4705 }
4706 return m;
4707 }
4708
4709
4710 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4711 if (idnum >= methods()->length()) {
4712 return nullptr;
4713 }
4714 Method* m = methods()->at(idnum);
4715 if (m != nullptr && m->orig_method_idnum() == idnum) {
4716 return m;
4717 }
4718 // Obsolete method idnum does not match the original idnum
4719 for (int index = 0; index < methods()->length(); ++index) {
4720 m = methods()->at(index);
4721 if (m->orig_method_idnum() == idnum) {
4722 return m;
4723 }
4724 }
4725 // None found, return null for the caller to handle.
4726 return nullptr;
4727 }
4728
4729
4730 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4731 InstanceKlass* holder = get_klass_version(version);
4732 if (holder == nullptr) {
4733 return nullptr; // The version of klass is gone, no method is found
4734 }
4735 Method* method = holder->method_with_orig_idnum(idnum);
4736 return method;
4737 }
4738
4739 #if INCLUDE_JVMTI
4740 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4741 return _cached_class_file;
4742 }
4743
4744 jint InstanceKlass::get_cached_class_file_len() {
4745 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4746 }
4747
4748 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4749 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4750 }
4751 #endif
4752
4753 // Make a step iterating over the class hierarchy under the root class.
4754 // Skips subclasses if requested.
4755 void ClassHierarchyIterator::next() {
4756 assert(_current != nullptr, "required");
4757 if (_visit_subclasses && _current->subklass() != nullptr) {
4758 _current = _current->subklass();
4759 return; // visit next subclass
4760 }
4761 _visit_subclasses = true; // reset
4762 while (_current->next_sibling() == nullptr && _current != _root) {
4763 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4764 }
4765 if (_current == _root) {
4766 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4767 _current = nullptr;
4768 return;
4769 }
4770 _current = _current->next_sibling();
4771 return; // visit next sibling subclass
4772 }