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/cdsEnumKlass.hpp"
29 #include "cds/classListWriter.hpp"
30 #include "cds/heapShared.hpp"
31 #include "cds/metaspaceShared.hpp"
32 #include "classfile/classFileParser.hpp"
33 #include "classfile/classFileStream.hpp"
34 #include "classfile/classLoader.hpp"
35 #include "classfile/classLoaderData.inline.hpp"
36 #include "classfile/javaClasses.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/verifier.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "code/codeCache.hpp"
44 #include "code/dependencyContext.hpp"
45 #include "compiler/compilationPolicy.hpp"
46 #include "compiler/compileBroker.hpp"
47 #include "gc/shared/collectedHeap.inline.hpp"
48 #include "interpreter/bytecodeStream.hpp"
49 #include "interpreter/oopMapCache.hpp"
50 #include "interpreter/rewriter.hpp"
51 #include "jvm.h"
52 #include "jvmtifiles/jvmti.h"
53 #include "logging/log.hpp"
54 #include "klass.inline.hpp"
55 #include "logging/logMessage.hpp"
56 #include "logging/logStream.hpp"
57 #include "memory/allocation.inline.hpp"
58 #include "memory/iterator.inline.hpp"
59 #include "memory/metadataFactory.hpp"
60 #include "memory/metaspaceClosure.hpp"
61 #include "memory/oopFactory.hpp"
62 #include "memory/resourceArea.hpp"
63 #include "memory/universe.hpp"
64 #include "oops/fieldStreams.inline.hpp"
65 #include "oops/constantPool.hpp"
66 #include "oops/instanceClassLoaderKlass.hpp"
67 #include "oops/instanceKlass.inline.hpp"
68 #include "oops/instanceMirrorKlass.hpp"
69 #include "oops/instanceOop.hpp"
70 #include "oops/instanceStackChunkKlass.hpp"
71 #include "oops/klass.inline.hpp"
72 #include "oops/method.hpp"
73 #include "oops/oop.inline.hpp"
74 #include "oops/recordComponent.hpp"
75 #include "oops/symbol.hpp"
76 #include "oops/inlineKlass.hpp"
77 #include "prims/jvmtiExport.hpp"
78 #include "prims/jvmtiRedefineClasses.hpp"
79 #include "prims/jvmtiThreadState.hpp"
80 #include "prims/methodComparator.hpp"
81 #include "runtime/arguments.hpp"
82 #include "runtime/deoptimization.hpp"
83 #include "runtime/atomic.hpp"
84 #include "runtime/fieldDescriptor.inline.hpp"
85 #include "runtime/handles.inline.hpp"
86 #include "runtime/javaCalls.hpp"
87 #include "runtime/javaThread.inline.hpp"
88 #include "runtime/mutexLocker.hpp"
89 #include "runtime/orderAccess.hpp"
90 #include "runtime/os.inline.hpp"
91 #include "runtime/reflection.hpp"
92 #include "runtime/synchronizer.hpp"
93 #include "runtime/threads.hpp"
94 #include "services/classLoadingService.hpp"
95 #include "services/finalizerService.hpp"
96 #include "services/threadService.hpp"
97 #include "utilities/dtrace.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/macros.hpp"
100 #include "utilities/stringUtils.hpp"
101 #include "utilities/pair.hpp"
102 #ifdef COMPILER1
103 #include "c1/c1_Compiler.hpp"
104 #endif
105 #if INCLUDE_JFR
106 #include "jfr/jfrEvents.hpp"
107 #endif
108
109 #ifdef DTRACE_ENABLED
110
111
112 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
113 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
114 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
115 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
116 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
117 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
118 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
119 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
120 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
121 { \
122 char* data = nullptr; \
123 int len = 0; \
124 Symbol* clss_name = name(); \
125 if (clss_name != nullptr) { \
126 data = (char*)clss_name->bytes(); \
127 len = clss_name->utf8_length(); \
128 } \
129 HOTSPOT_CLASS_INITIALIZATION_##type( \
130 data, len, (void*)class_loader(), thread_type); \
131 }
132
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
134 { \
135 char* data = nullptr; \
136 int len = 0; \
137 Symbol* clss_name = name(); \
138 if (clss_name != nullptr) { \
139 data = (char*)clss_name->bytes(); \
140 len = clss_name->utf8_length(); \
141 } \
142 HOTSPOT_CLASS_INITIALIZATION_##type( \
143 data, len, (void*)class_loader(), thread_type, wait); \
144 }
145
146 #else // ndef DTRACE_ENABLED
147
148 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
149 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
150
151 #endif // ndef DTRACE_ENABLED
152
153 void InlineLayoutInfo::metaspace_pointers_do(MetaspaceClosure* it) {
154 log_trace(cds)("Iter(InlineFieldInfo): %p", this);
155 it->push(&_klass);
156 }
157
158 bool InstanceKlass::_finalization_enabled = true;
159
160 static inline bool is_class_loader(const Symbol* class_name,
161 const ClassFileParser& parser) {
162 assert(class_name != nullptr, "invariant");
163
164 if (class_name == vmSymbols::java_lang_ClassLoader()) {
165 return true;
166 }
167
168 if (vmClasses::ClassLoader_klass_loaded()) {
169 const Klass* const super_klass = parser.super_klass();
170 if (super_klass != nullptr) {
171 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
172 return true;
173 }
174 }
175 }
176 return false;
177 }
178
179 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
180 return field(index).field_flags().is_null_free_inline_type();
181 }
182
183 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
184 if (_loadable_descriptors == nullptr) return false;
185 for (int i = 0; i < _loadable_descriptors->length(); i++) {
186 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
187 if (class_name == name) return true;
188 }
189 return false;
190 }
191
192 static inline bool is_stack_chunk_class(const Symbol* class_name,
193 const ClassLoaderData* loader_data) {
194 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
195 loader_data->is_the_null_class_loader_data());
196 }
197
198 // private: called to verify that k is a static member of this nest.
199 // We know that k is an instance class in the same package and hence the
200 // same classloader.
201 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
202 assert(!is_hidden(), "unexpected hidden class");
203 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
204 if (log_is_enabled(Trace, class, nestmates)) {
205 ResourceMark rm(current);
206 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
207 k->external_name(), this->external_name());
208 }
209 return false;
210 }
211
212 if (log_is_enabled(Trace, class, nestmates)) {
213 ResourceMark rm(current);
214 log_trace(class, nestmates)("Checking nest membership of %s in %s",
215 k->external_name(), this->external_name());
216 }
217
218 // Check for the named class in _nest_members.
219 // We don't resolve, or load, any classes.
220 for (int i = 0; i < _nest_members->length(); i++) {
221 int cp_index = _nest_members->at(i);
222 Symbol* name = _constants->klass_name_at(cp_index);
223 if (name == k->name()) {
224 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
225 return true;
226 }
227 }
228 log_trace(class, nestmates)("- class is NOT a nest member!");
229 return false;
230 }
231
232 // Called to verify that k is a permitted subclass of this class
233 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
234 Thread* current = Thread::current();
235 assert(k != nullptr, "sanity check");
236 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
237 "unexpected empty _permitted_subclasses array");
238
239 if (log_is_enabled(Trace, class, sealed)) {
240 ResourceMark rm(current);
241 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
242 k->external_name(), this->external_name());
243 }
244
245 // Check that the class and its super are in the same module.
246 if (k->module() != this->module()) {
247 ResourceMark rm(current);
248 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
249 k->external_name(), this->external_name());
250 return false;
251 }
252
253 if (!k->is_public() && !is_same_class_package(k)) {
254 ResourceMark rm(current);
255 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
256 k->external_name(), this->external_name());
257 return false;
258 }
259
260 for (int i = 0; i < _permitted_subclasses->length(); i++) {
261 int cp_index = _permitted_subclasses->at(i);
262 Symbol* name = _constants->klass_name_at(cp_index);
263 if (name == k->name()) {
264 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
265 return true;
266 }
267 }
268 log_trace(class, sealed)("- class is NOT a permitted subclass!");
269 return false;
270 }
271
272 // Return nest-host class, resolving, validating and saving it if needed.
273 // In cases where this is called from a thread that cannot do classloading
274 // (such as a native JIT thread) then we simply return null, which in turn
275 // causes the access check to return false. Such code will retry the access
276 // from a more suitable environment later. Otherwise the _nest_host is always
277 // set once this method returns.
278 // Any errors from nest-host resolution must be preserved so they can be queried
279 // from higher-level access checking code, and reported as part of access checking
280 // exceptions.
281 // VirtualMachineErrors are propagated with a null return.
282 // Under any conditions where the _nest_host can be set to non-null the resulting
283 // value of it and, if applicable, the nest host resolution/validation error,
284 // are idempotent.
285 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
286 InstanceKlass* nest_host_k = _nest_host;
287 if (nest_host_k != nullptr) {
288 return nest_host_k;
289 }
290
291 ResourceMark rm(THREAD);
292
293 // need to resolve and save our nest-host class.
294 if (_nest_host_index != 0) { // we have a real nest_host
295 // Before trying to resolve check if we're in a suitable context
296 bool can_resolve = THREAD->can_call_java();
297 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
298 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
299 this->external_name());
300 return nullptr; // sentinel to say "try again from a different context"
301 }
302
303 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
304 this->external_name(),
305 _constants->klass_name_at(_nest_host_index)->as_C_string());
306
307 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
308 if (HAS_PENDING_EXCEPTION) {
309 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
310 return nullptr; // propagate VMEs
311 }
312 stringStream ss;
313 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
314 ss.print("Nest host resolution of %s with host %s failed: ",
315 this->external_name(), target_host_class);
316 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
317 const char* msg = ss.as_string(true /* on C-heap */);
318 constantPoolHandle cph(THREAD, constants());
319 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
320 CLEAR_PENDING_EXCEPTION;
321
322 log_trace(class, nestmates)("%s", msg);
323 } else {
324 // A valid nest-host is an instance class in the current package that lists this
325 // class as a nest member. If any of these conditions are not met the class is
326 // its own nest-host.
327 const char* error = nullptr;
328
329 // JVMS 5.4.4 indicates package check comes first
330 if (is_same_class_package(k)) {
331 // Now check actual membership. We can't be a member if our "host" is
332 // not an instance class.
333 if (k->is_instance_klass()) {
334 nest_host_k = InstanceKlass::cast(k);
335 bool is_member = nest_host_k->has_nest_member(THREAD, this);
336 if (is_member) {
337 _nest_host = nest_host_k; // save resolved nest-host value
338
339 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
340 this->external_name(), k->external_name());
341 return nest_host_k;
342 } else {
343 error = "current type is not listed as a nest member";
344 }
345 } else {
346 error = "host is not an instance class";
347 }
348 } else {
349 error = "types are in different packages";
350 }
351
352 // something went wrong, so record what and log it
353 {
354 stringStream ss;
355 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
356 this->external_name(),
357 this->class_loader_data()->loader_name_and_id(),
358 k->external_name(),
359 k->class_loader_data()->loader_name_and_id(),
360 error);
361 const char* msg = ss.as_string(true /* on C-heap */);
362 constantPoolHandle cph(THREAD, constants());
363 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
364 log_trace(class, nestmates)("%s", msg);
365 }
366 }
367 } else {
368 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
369 this->external_name());
370 }
371
372 // Either not in an explicit nest, or else an error occurred, so
373 // the nest-host is set to `this`. Any thread that sees this assignment
374 // will also see any setting of nest_host_error(), if applicable.
375 return (_nest_host = this);
376 }
377
378 // Dynamic nest member support: set this class's nest host to the given class.
379 // This occurs as part of the class definition, as soon as the instanceKlass
380 // has been created and doesn't require further resolution. The code:
381 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
382 // results in:
383 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
384 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
385 // We also know the "host" is a valid nest-host in the same package so we can
386 // assert some of those facts.
387 void InstanceKlass::set_nest_host(InstanceKlass* host) {
388 assert(is_hidden(), "must be a hidden class");
389 assert(host != nullptr, "null nest host specified");
390 assert(_nest_host == nullptr, "current class has resolved nest-host");
391 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
392 nest_host_error());
393 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
394 (host->_nest_host == host), "proposed host is not a valid nest-host");
395 // Can't assert this as package is not set yet:
396 // assert(is_same_class_package(host), "proposed host is in wrong package");
397
398 if (log_is_enabled(Trace, class, nestmates)) {
399 ResourceMark rm;
400 const char* msg = "";
401 // a hidden class does not expect a statically defined nest-host
402 if (_nest_host_index > 0) {
403 msg = "(the NestHost attribute in the current class is ignored)";
404 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
405 msg = "(the NestMembers attribute in the current class is ignored)";
406 }
407 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
408 this->external_name(),
409 host->external_name(),
410 msg);
411 }
412 // set dynamic nest host
413 _nest_host = host;
414 // Record dependency to keep nest host from being unloaded before this class.
415 ClassLoaderData* this_key = class_loader_data();
416 assert(this_key != nullptr, "sanity");
417 this_key->record_dependency(host);
418 }
419
420 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
421 // or we are k's nest_host - all of which is covered by comparing the two
422 // resolved_nest_hosts.
423 // Any exceptions (i.e. VMEs) are propagated.
424 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
425
426 assert(this != k, "this should be handled by higher-level code");
427
428 // Per JVMS 5.4.4 we first resolve and validate the current class, then
429 // the target class k.
430
431 InstanceKlass* cur_host = nest_host(CHECK_false);
432 if (cur_host == nullptr) {
433 return false;
434 }
435
436 Klass* k_nest_host = k->nest_host(CHECK_false);
437 if (k_nest_host == nullptr) {
438 return false;
439 }
440
441 bool access = (cur_host == k_nest_host);
442
443 ResourceMark rm(THREAD);
444 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
445 this->external_name(),
446 access ? "" : "NOT ",
447 k->external_name());
448 return access;
449 }
450
451 const char* InstanceKlass::nest_host_error() {
452 if (_nest_host_index == 0) {
453 return nullptr;
454 } else {
455 constantPoolHandle cph(Thread::current(), constants());
456 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
457 }
458 }
459
460 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
461 bool use_class_space, TRAPS) throw() {
462 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
463 }
464
465 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
466 const int size = InstanceKlass::size(parser.vtable_size(),
467 parser.itable_size(),
468 nonstatic_oop_map_size(parser.total_oop_map_count()),
469 parser.is_interface(),
470 parser.is_inline_type());
471
472 const Symbol* const class_name = parser.class_name();
473 assert(class_name != nullptr, "invariant");
474 ClassLoaderData* loader_data = parser.loader_data();
475 assert(loader_data != nullptr, "invariant");
476
477 InstanceKlass* ik;
478 const bool use_class_space = !parser.is_interface() && !parser.is_abstract();
479
480 // Allocation
481 if (parser.is_instance_ref_klass()) {
482 // java.lang.ref.Reference
483 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
484 } else if (class_name == vmSymbols::java_lang_Class()) {
485 // mirror - java.lang.Class
486 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
487 } else if (is_stack_chunk_class(class_name, loader_data)) {
488 // stack chunk
489 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
490 } else if (is_class_loader(class_name, parser)) {
491 // class loader - java.lang.ClassLoader
492 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
493 } else if (parser.is_inline_type()) {
494 // inline type
495 ik = new (loader_data, size, use_class_space, THREAD) InlineKlass(parser);
496 } else {
497 // normal
498 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
499 }
500
501 // Check for pending exception before adding to the loader data and incrementing
502 // class count. Can get OOM here.
503 if (HAS_PENDING_EXCEPTION) {
504 return nullptr;
505 }
506
507 #ifdef ASSERT
508 ik->bounds_check((address) ik->start_of_vtable(), false, size);
509 ik->bounds_check((address) ik->start_of_itable(), false, size);
510 ik->bounds_check((address) ik->end_of_itable(), true, size);
511 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
512 #endif //ASSERT
513 return ik;
514 }
515
516 #ifndef PRODUCT
517 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
518 const char* bad = nullptr;
519 address end = nullptr;
520 if (addr < (address)this) {
521 bad = "before";
522 } else if (addr == (address)this) {
523 if (edge_ok) return true;
524 bad = "just before";
525 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
526 if (edge_ok) return true;
527 bad = "just after";
528 } else if (addr > end) {
529 bad = "after";
530 } else {
531 return true;
532 }
533 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
534 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
535 Verbose = WizardMode = true; this->print(); //@@
536 return false;
537 }
538 #endif //PRODUCT
539
540 // copy method ordering from resource area to Metaspace
541 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
542 if (m != nullptr) {
543 // allocate a new array and copy contents (memcpy?)
544 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
545 for (int i = 0; i < m->length(); i++) {
546 _method_ordering->at_put(i, m->at(i));
547 }
548 } else {
549 _method_ordering = Universe::the_empty_int_array();
550 }
551 }
552
553 // create a new array of vtable_indices for default methods
554 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
555 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
556 assert(default_vtable_indices() == nullptr, "only create once");
557 set_default_vtable_indices(vtable_indices);
558 return vtable_indices;
559 }
560
561
562 InstanceKlass::InstanceKlass() {
563 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
564 }
565
566 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
567 Klass(kind),
568 _nest_members(nullptr),
569 _nest_host(nullptr),
570 _permitted_subclasses(nullptr),
571 _record_components(nullptr),
572 _static_field_size(parser.static_field_size()),
573 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
574 _itable_len(parser.itable_size()),
575 _nest_host_index(0),
576 _init_state(allocated),
577 _reference_type(reference_type),
578 _init_thread(nullptr),
579 _inline_layout_info_array(nullptr),
580 _loadable_descriptors(nullptr),
581 _adr_inlineklass_fixed_block(nullptr)
582 {
583 set_vtable_length(parser.vtable_size());
584 set_access_flags(parser.access_flags());
585 if (parser.is_hidden()) set_is_hidden();
586 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
587 false));
588 if (parser.has_inline_fields()) {
589 set_has_inline_type_fields();
590 }
591
592 assert(nullptr == _methods, "underlying memory not zeroed?");
593 assert(is_instance_klass(), "is layout incorrect?");
594 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
595 }
596
597 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
598 Array<Method*>* methods) {
599 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
600 !methods->is_shared()) {
601 for (int i = 0; i < methods->length(); i++) {
602 Method* method = methods->at(i);
603 if (method == nullptr) continue; // maybe null if error processing
604 // Only want to delete methods that are not executing for RedefineClasses.
605 // The previous version will point to them so they're not totally dangling
606 assert (!method->on_stack(), "shouldn't be called with methods on stack");
607 MetadataFactory::free_metadata(loader_data, method);
608 }
609 MetadataFactory::free_array<Method*>(loader_data, methods);
610 }
611 }
612
613 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
614 const Klass* super_klass,
615 Array<InstanceKlass*>* local_interfaces,
616 Array<InstanceKlass*>* transitive_interfaces) {
617 // Only deallocate transitive interfaces if not empty, same as super class
618 // or same as local interfaces. See code in parseClassFile.
619 Array<InstanceKlass*>* ti = transitive_interfaces;
620 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
621 // check that the interfaces don't come from super class
622 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
623 InstanceKlass::cast(super_klass)->transitive_interfaces();
624 if (ti != sti && ti != nullptr && !ti->is_shared()) {
625 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
626 }
627 }
628
629 // local interfaces can be empty
630 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
631 local_interfaces != nullptr && !local_interfaces->is_shared()) {
632 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
633 }
634 }
635
636 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
637 Array<RecordComponent*>* record_components) {
638 if (record_components != nullptr && !record_components->is_shared()) {
639 for (int i = 0; i < record_components->length(); i++) {
640 RecordComponent* record_component = record_components->at(i);
641 MetadataFactory::free_metadata(loader_data, record_component);
642 }
643 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
644 }
645 }
646
647 // This function deallocates the metadata and C heap pointers that the
648 // InstanceKlass points to.
649 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
650 // Orphan the mirror first, CMS thinks it's still live.
651 if (java_mirror() != nullptr) {
652 java_lang_Class::set_klass(java_mirror(), nullptr);
653 }
654
655 // Also remove mirror from handles
656 loader_data->remove_handle(_java_mirror);
657
658 // Need to take this class off the class loader data list.
659 loader_data->remove_class(this);
660
661 // The array_klass for this class is created later, after error handling.
662 // For class redefinition, we keep the original class so this scratch class
663 // doesn't have an array class. Either way, assert that there is nothing
664 // to deallocate.
665 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
666
667 // Release C heap allocated data that this points to, which includes
668 // reference counting symbol names.
669 // Can't release the constant pool or MethodData C heap data here because the constant
670 // pool can be deallocated separately from the InstanceKlass for default methods and
671 // redefine classes. MethodData can also be released separately.
672 release_C_heap_structures(/* release_sub_metadata */ false);
673
674 deallocate_methods(loader_data, methods());
675 set_methods(nullptr);
676
677 deallocate_record_components(loader_data, record_components());
678 set_record_components(nullptr);
679
680 if (method_ordering() != nullptr &&
681 method_ordering() != Universe::the_empty_int_array() &&
682 !method_ordering()->is_shared()) {
683 MetadataFactory::free_array<int>(loader_data, method_ordering());
684 }
685 set_method_ordering(nullptr);
686
687 // default methods can be empty
688 if (default_methods() != nullptr &&
689 default_methods() != Universe::the_empty_method_array() &&
690 !default_methods()->is_shared()) {
691 MetadataFactory::free_array<Method*>(loader_data, default_methods());
692 }
693 // Do NOT deallocate the default methods, they are owned by superinterfaces.
694 set_default_methods(nullptr);
695
696 // default methods vtable indices can be empty
697 if (default_vtable_indices() != nullptr &&
698 !default_vtable_indices()->is_shared()) {
699 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
700 }
701 set_default_vtable_indices(nullptr);
702
703
704 // This array is in Klass, but remove it with the InstanceKlass since
705 // this place would be the only caller and it can share memory with transitive
706 // interfaces.
707 if (secondary_supers() != nullptr &&
708 secondary_supers() != Universe::the_empty_klass_array() &&
709 // see comments in compute_secondary_supers about the following cast
710 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
711 !secondary_supers()->is_shared()) {
712 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
713 }
714 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY);
715
716 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
717 set_transitive_interfaces(nullptr);
718 set_local_interfaces(nullptr);
719
720 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
721 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
722 }
723 set_fieldinfo_stream(nullptr);
724
725 if (fields_status() != nullptr && !fields_status()->is_shared()) {
726 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
727 }
728 set_fields_status(nullptr);
729
730 if (inline_layout_info_array() != nullptr) {
731 MetadataFactory::free_array<InlineLayoutInfo>(loader_data, inline_layout_info_array());
732 }
733 set_inline_layout_info_array(nullptr);
734
735 // If a method from a redefined class is using this constant pool, don't
736 // delete it, yet. The new class's previous version will point to this.
737 if (constants() != nullptr) {
738 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
739 if (!constants()->is_shared()) {
740 MetadataFactory::free_metadata(loader_data, constants());
741 }
742 // Delete any cached resolution errors for the constant pool
743 SystemDictionary::delete_resolution_error(constants());
744
745 set_constants(nullptr);
746 }
747
748 if (inner_classes() != nullptr &&
749 inner_classes() != Universe::the_empty_short_array() &&
750 !inner_classes()->is_shared()) {
751 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
752 }
753 set_inner_classes(nullptr);
754
755 if (nest_members() != nullptr &&
756 nest_members() != Universe::the_empty_short_array() &&
757 !nest_members()->is_shared()) {
758 MetadataFactory::free_array<jushort>(loader_data, nest_members());
759 }
760 set_nest_members(nullptr);
761
762 if (permitted_subclasses() != nullptr &&
763 permitted_subclasses() != Universe::the_empty_short_array() &&
764 !permitted_subclasses()->is_shared()) {
765 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
766 }
767 set_permitted_subclasses(nullptr);
768
769 if (loadable_descriptors() != nullptr &&
770 loadable_descriptors() != Universe::the_empty_short_array() &&
771 !loadable_descriptors()->is_shared()) {
772 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
773 }
774 set_loadable_descriptors(nullptr);
775
776 // We should deallocate the Annotations instance if it's not in shared spaces.
777 if (annotations() != nullptr && !annotations()->is_shared()) {
778 MetadataFactory::free_metadata(loader_data, annotations());
779 }
780 set_annotations(nullptr);
781
782 SystemDictionaryShared::handle_class_unloading(this);
783
784 #if INCLUDE_CDS_JAVA_HEAP
785 if (CDSConfig::is_dumping_heap()) {
786 HeapShared::remove_scratch_objects(this);
787 }
788 #endif
789 }
790
791 bool InstanceKlass::is_record() const {
792 return _record_components != nullptr &&
793 is_final() &&
794 java_super() == vmClasses::Record_klass();
795 }
796
797 bool InstanceKlass::is_sealed() const {
798 return _permitted_subclasses != nullptr &&
799 _permitted_subclasses != Universe::the_empty_short_array();
800 }
801
802 bool InstanceKlass::should_be_initialized() const {
803 return !is_initialized();
804 }
805
806 klassItable InstanceKlass::itable() const {
807 return klassItable(const_cast<InstanceKlass*>(this));
808 }
809
810 // JVMTI spec thinks there are signers and protection domain in the
811 // instanceKlass. These accessors pretend these fields are there.
812 // The hprof specification also thinks these fields are in InstanceKlass.
813 oop InstanceKlass::protection_domain() const {
814 // return the protection_domain from the mirror
815 return java_lang_Class::protection_domain(java_mirror());
816 }
817
818 objArrayOop InstanceKlass::signers() const {
819 // return the signers from the mirror
820 return java_lang_Class::signers(java_mirror());
821 }
822
823 oop InstanceKlass::init_lock() const {
824 // return the init lock from the mirror
825 oop lock = java_lang_Class::init_lock(java_mirror());
826 // Prevent reordering with any access of initialization state
827 OrderAccess::loadload();
828 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
829 "only fully initialized state can have a null lock");
830 return lock;
831 }
832
833 // Set the initialization lock to null so the object can be GC'ed. Any racing
834 // threads to get this lock will see a null lock and will not lock.
835 // That's okay because they all check for initialized state after getting
836 // the lock and return.
837 void InstanceKlass::fence_and_clear_init_lock() {
838 // make sure previous stores are all done, notably the init_state.
839 OrderAccess::storestore();
840 java_lang_Class::clear_init_lock(java_mirror());
841 assert(!is_not_initialized(), "class must be initialized now");
842 }
843
844
845 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
846 // process. The step comments refers to the procedure described in that section.
847 // Note: implementation moved to static method to expose the this pointer.
848 void InstanceKlass::initialize(TRAPS) {
849 if (this->should_be_initialized()) {
850 initialize_impl(CHECK);
851 // Note: at this point the class may be initialized
852 // OR it may be in the state of being initialized
853 // in case of recursive initialization!
854 } else {
855 assert(is_initialized(), "sanity check");
856 }
857 }
858
859
860 bool InstanceKlass::verify_code(TRAPS) {
861 // 1) Verify the bytecodes
862 return Verifier::verify(this, should_verify_class(), THREAD);
863 }
864
865 void InstanceKlass::link_class(TRAPS) {
866 assert(is_loaded(), "must be loaded");
867 if (!is_linked()) {
868 link_class_impl(CHECK);
869 }
870 }
871
872 // Called to verify that a class can link during initialization, without
873 // throwing a VerifyError.
874 bool InstanceKlass::link_class_or_fail(TRAPS) {
875 assert(is_loaded(), "must be loaded");
876 if (!is_linked()) {
877 link_class_impl(CHECK_false);
878 }
879 return is_linked();
880 }
881
882 bool InstanceKlass::link_class_impl(TRAPS) {
883 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
884 // This is for CDS static dump only -- we use the in_error_state to indicate that
885 // the class has failed verification. Throwing the NoClassDefFoundError here is just
886 // a convenient way to stop repeat attempts to verify the same (bad) class.
887 //
888 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
889 // if we are executing Java code. This is not a problem for CDS dumping phase since
890 // it doesn't execute any Java code.
891 ResourceMark rm(THREAD);
892 Exceptions::fthrow(THREAD_AND_LOCATION,
893 vmSymbols::java_lang_NoClassDefFoundError(),
894 "Class %s, or one of its supertypes, failed class initialization",
895 external_name());
896 return false;
897 }
898 // return if already verified
899 if (is_linked()) {
900 return true;
901 }
902
903 // Timing
904 // timer handles recursion
905 JavaThread* jt = THREAD;
906
907 // link super class before linking this class
908 Klass* super_klass = super();
909 if (super_klass != nullptr) {
910 if (super_klass->is_interface()) { // check if super class is an interface
911 ResourceMark rm(THREAD);
912 Exceptions::fthrow(
913 THREAD_AND_LOCATION,
914 vmSymbols::java_lang_IncompatibleClassChangeError(),
915 "class %s has interface %s as super class",
916 external_name(),
917 super_klass->external_name()
918 );
919 return false;
920 }
921
922 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
923 ik_super->link_class_impl(CHECK_false);
924 }
925
926 // link all interfaces implemented by this class before linking this class
927 Array<InstanceKlass*>* interfaces = local_interfaces();
928 int num_interfaces = interfaces->length();
929 for (int index = 0; index < num_interfaces; index++) {
930 InstanceKlass* interk = interfaces->at(index);
931 interk->link_class_impl(CHECK_false);
932 }
933
934
935 // If a class declares a method that uses an inline class as an argument
936 // type or return inline type, this inline class must be loaded during the
937 // linking of this class because size and properties of the inline class
938 // must be known in order to be able to perform inline type optimizations.
939 // The implementation below is an approximation of this rule, the code
940 // iterates over all methods of the current class (including overridden
941 // methods), not only the methods declared by this class. This
942 // approximation makes the code simpler, and doesn't change the semantic
943 // because classes declaring methods overridden by the current class are
944 // linked (and have performed their own pre-loading) before the linking
945 // of the current class.
946
947
948 // Note:
949 // Inline class types are loaded during
950 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
951 // Inline class types used as element types for array creation
952 // are not pre-loaded. Their loading is triggered by either anewarray
953 // or multianewarray bytecodes.
954
955 // Could it be possible to do the following processing only if the
956 // class uses inline types?
957 if (EnableValhalla) {
958 ResourceMark rm(THREAD);
959 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
960 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) {
961 Symbol* sig = fs.signature();
962 TempNewSymbol s = Signature::strip_envelope(sig);
963 if (s != name()) {
964 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());
965 Klass* klass = SystemDictionary::resolve_or_fail(s,
966 Handle(THREAD, class_loader()), Handle(THREAD, protection_domain()), true,
967 CHECK_false);
968 if (HAS_PENDING_EXCEPTION) {
969 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s",
970 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string());
971 return false; // Exception is still pending
972 }
973 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded",
974 s->as_C_string(), name()->as_C_string());
975 assert(klass != nullptr, "Sanity check");
976 if (klass->is_abstract()) {
977 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
978 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class",
979 name()->as_C_string(),
980 InstanceKlass::cast(klass)->external_name()), false);
981 }
982 if (!klass->is_inline_klass()) {
983 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
984 err_msg("class %s expects class %s to be a value class but it is an identity class",
985 name()->as_C_string(), klass->external_name()), false);
986 }
987 InlineKlass* vk = InlineKlass::cast(klass);
988 if (!vk->is_implicitly_constructible()) {
989 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
990 err_msg("class %s is not implicitly constructible and it is used in a null restricted static field (not supported)",
991 klass->external_name()), false);
992 }
993 // the inline_type_field_klasses_array might have been loaded with CDS, so update only if not already set and check consistency
994 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
995 if (li->klass() == nullptr) {
996 li->set_klass(InlineKlass::cast(vk));
997 li->set_kind(LayoutKind::REFERENCE);
998 }
999 assert(get_inline_type_field_klass(fs.index()) == vk, "Must match");
1000 } else {
1001 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
1002 if (li->klass() == nullptr) {
1003 li->set_klass(InlineKlass::cast(this));
1004 li->set_kind(LayoutKind::REFERENCE);
1005 }
1006 assert(get_inline_type_field_klass(fs.index()) == this, "Must match");
1007 }
1008 }
1009 }
1010
1011 // Aggressively preloading all classes from the LoadableDescriptors attribute
1012 if (loadable_descriptors() != nullptr) {
1013 HandleMark hm(THREAD);
1014 for (int i = 0; i < loadable_descriptors()->length(); i++) {
1015 Symbol* sig = constants()->symbol_at(loadable_descriptors()->at(i));
1016 if (!Signature::has_envelope(sig)) continue;
1017 TempNewSymbol class_name = Signature::strip_envelope(sig);
1018 if (class_name == name()) continue;
1019 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());
1020 oop loader = class_loader();
1021 oop protection_domain = this->protection_domain();
1022 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1023 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD);
1024 if (HAS_PENDING_EXCEPTION) {
1025 CLEAR_PENDING_EXCEPTION;
1026 }
1027 if (klass != nullptr) {
1028 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());
1029 if (!klass->is_inline_klass()) {
1030 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning
1031 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());
1032 }
1033 } else {
1034 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());
1035 }
1036 }
1037 }
1038 }
1039
1040 // in case the class is linked in the process of linking its superclasses
1041 if (is_linked()) {
1042 return true;
1043 }
1044
1045 // trace only the link time for this klass that includes
1046 // the verification time
1047 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1048 ClassLoader::perf_class_link_selftime(),
1049 ClassLoader::perf_classes_linked(),
1050 jt->get_thread_stat()->perf_recursion_counts_addr(),
1051 jt->get_thread_stat()->perf_timers_addr(),
1052 PerfClassTraceTime::CLASS_LINK);
1053
1054 // verification & rewriting
1055 {
1056 HandleMark hm(THREAD);
1057 Handle h_init_lock(THREAD, init_lock());
1058 ObjectLocker ol(h_init_lock, jt);
1059 // rewritten will have been set if loader constraint error found
1060 // on an earlier link attempt
1061 // don't verify or rewrite if already rewritten
1062 //
1063
1064 if (!is_linked()) {
1065 if (!is_rewritten()) {
1066 if (is_shared()) {
1067 assert(!verified_at_dump_time(), "must be");
1068 }
1069 {
1070 bool verify_ok = verify_code(THREAD);
1071 if (!verify_ok) {
1072 return false;
1073 }
1074 }
1075
1076 // Just in case a side-effect of verify linked this class already
1077 // (which can sometimes happen since the verifier loads classes
1078 // using custom class loaders, which are free to initialize things)
1079 if (is_linked()) {
1080 return true;
1081 }
1082
1083 // also sets rewritten
1084 rewrite_class(CHECK_false);
1085 } else if (is_shared()) {
1086 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1087 }
1088
1089 // relocate jsrs and link methods after they are all rewritten
1090 link_methods(CHECK_false);
1091
1092 // Initialize the vtable and interface table after
1093 // methods have been rewritten since rewrite may
1094 // fabricate new Method*s.
1095 // also does loader constraint checking
1096 //
1097 // initialize_vtable and initialize_itable need to be rerun
1098 // for a shared class if
1099 // 1) the class is loaded by custom class loader or
1100 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1101 // 3) the class was not verified during dump time
1102 bool need_init_table = true;
1103 if (is_shared() && verified_at_dump_time() &&
1104 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1105 need_init_table = false;
1106 }
1107 if (need_init_table) {
1108 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1109 itable().initialize_itable_and_check_constraints(CHECK_false);
1110 }
1111 #ifdef ASSERT
1112 vtable().verify(tty, true);
1113 // In case itable verification is ever added.
1114 // itable().verify(tty, true);
1115 #endif
1116 if (Universe::is_fully_initialized()) {
1117 DeoptimizationScope deopt_scope;
1118 {
1119 // Now mark all code that assumes the class is not linked.
1120 // Set state under the Compile_lock also.
1121 MutexLocker ml(THREAD, Compile_lock);
1122
1123 set_init_state(linked);
1124 CodeCache::mark_dependents_on(&deopt_scope, this);
1125 }
1126 // Perform the deopt handshake outside Compile_lock.
1127 deopt_scope.deoptimize_marked();
1128 } else {
1129 set_init_state(linked);
1130 }
1131 if (JvmtiExport::should_post_class_prepare()) {
1132 JvmtiExport::post_class_prepare(THREAD, this);
1133 }
1134 }
1135 }
1136 return true;
1137 }
1138
1139 // Rewrite the byte codes of all of the methods of a class.
1140 // The rewriter must be called exactly once. Rewriting must happen after
1141 // verification but before the first method of the class is executed.
1142 void InstanceKlass::rewrite_class(TRAPS) {
1143 assert(is_loaded(), "must be loaded");
1144 if (is_rewritten()) {
1145 assert(is_shared(), "rewriting an unshared class?");
1146 return;
1147 }
1148 Rewriter::rewrite(this, CHECK);
1149 set_rewritten();
1150 }
1151
1152 // Now relocate and link method entry points after class is rewritten.
1153 // This is outside is_rewritten flag. In case of an exception, it can be
1154 // executed more than once.
1155 void InstanceKlass::link_methods(TRAPS) {
1156 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1157
1158 int len = methods()->length();
1159 for (int i = len-1; i >= 0; i--) {
1160 methodHandle m(THREAD, methods()->at(i));
1161
1162 // Set up method entry points for compiler and interpreter .
1163 m->link_method(m, CHECK);
1164 }
1165 }
1166
1167 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1168 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1169 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1170 for (int i = 0; i < local_interfaces()->length(); ++i) {
1171 InstanceKlass* ik = local_interfaces()->at(i);
1172
1173 // Initialization is depth first search ie. we start with top of the inheritance tree
1174 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1175 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1176 if (ik->has_nonstatic_concrete_methods()) {
1177 ik->initialize_super_interfaces(CHECK);
1178 }
1179
1180 // Only initialize() interfaces that "declare" concrete methods.
1181 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1182 ik->initialize(CHECK);
1183 }
1184 }
1185 }
1186
1187 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1188 static InitializationErrorTable* _initialization_error_table;
1189
1190 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1191 // Create the same exception with a message indicating the thread name,
1192 // and the StackTraceElements.
1193 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1194 ResourceMark rm(current);
1195 if (init_error.is_null()) {
1196 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1197
1198 // We failed to create the new exception, most likely due to either out-of-memory or
1199 // a stackoverflow error. If the original exception was either of those then we save
1200 // the shared, pre-allocated, stackless, instance of that exception.
1201 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1202 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1203 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1204 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1205 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1206 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1207 } else {
1208 return;
1209 }
1210 }
1211
1212 MutexLocker ml(current, ClassInitError_lock);
1213 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1214 bool created;
1215 if (_initialization_error_table == nullptr) {
1216 _initialization_error_table = new (mtClass) InitializationErrorTable();
1217 }
1218 _initialization_error_table->put_if_absent(this, elem, &created);
1219 assert(created, "Initialization is single threaded");
1220 log_trace(class, init)("Initialization error added for class %s", external_name());
1221 }
1222
1223 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1224 MutexLocker ml(current, ClassInitError_lock);
1225 if (_initialization_error_table == nullptr) {
1226 return nullptr;
1227 }
1228 OopHandle* h = _initialization_error_table->get(this);
1229 return (h != nullptr) ? h->resolve() : nullptr;
1230 }
1231
1232 // Need to remove entries for unloaded classes.
1233 void InstanceKlass::clean_initialization_error_table() {
1234 struct InitErrorTableCleaner {
1235 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1236 if (!ik->is_loader_alive()) {
1237 h.release(Universe::vm_global());
1238 return true;
1239 } else {
1240 return false;
1241 }
1242 }
1243 };
1244
1245 assert_locked_or_safepoint(ClassInitError_lock);
1246 InitErrorTableCleaner cleaner;
1247 if (_initialization_error_table != nullptr) {
1248 _initialization_error_table->unlink(&cleaner);
1249 }
1250 }
1251
1252 void InstanceKlass::initialize_impl(TRAPS) {
1253 HandleMark hm(THREAD);
1254
1255 // Make sure klass is linked (verified) before initialization
1256 // A class could already be verified, since it has been reflected upon.
1257 link_class(CHECK);
1258
1259 DTRACE_CLASSINIT_PROBE(required, -1);
1260
1261 bool wait = false;
1262
1263 JavaThread* jt = THREAD;
1264
1265 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1266
1267 // refer to the JVM book page 47 for description of steps
1268 // Step 1
1269 {
1270 Handle h_init_lock(THREAD, init_lock());
1271 ObjectLocker ol(h_init_lock, jt);
1272
1273 // Step 2
1274 // If we were to use wait() instead of waitInterruptibly() then
1275 // we might end up throwing IE from link/symbol resolution sites
1276 // that aren't expected to throw. This would wreak havoc. See 6320309.
1277 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1278 if (debug_logging_enabled) {
1279 ResourceMark rm(jt);
1280 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1281 jt->name(), external_name(), init_thread_name());
1282 }
1283 wait = true;
1284 jt->set_class_to_be_initialized(this);
1285 ol.wait_uninterruptibly(jt);
1286 jt->set_class_to_be_initialized(nullptr);
1287 }
1288
1289 // Step 3
1290 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1291 if (debug_logging_enabled) {
1292 ResourceMark rm(jt);
1293 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1294 jt->name(), external_name());
1295 }
1296 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1297 return;
1298 }
1299
1300 // Step 4
1301 if (is_initialized()) {
1302 if (debug_logging_enabled) {
1303 ResourceMark rm(jt);
1304 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1305 jt->name(), external_name());
1306 }
1307 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1308 return;
1309 }
1310
1311 // Step 5
1312 if (is_in_error_state()) {
1313 if (debug_logging_enabled) {
1314 ResourceMark rm(jt);
1315 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1316 jt->name(), external_name());
1317 }
1318
1319 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1320 ResourceMark rm(THREAD);
1321 Handle cause(THREAD, get_initialization_error(THREAD));
1322
1323 stringStream ss;
1324 ss.print("Could not initialize class %s", external_name());
1325 if (cause.is_null()) {
1326 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1327 } else {
1328 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1329 ss.as_string(), cause);
1330 }
1331 } else {
1332
1333 // Step 6
1334 set_init_state(being_initialized);
1335 set_init_thread(jt);
1336 if (debug_logging_enabled) {
1337 ResourceMark rm(jt);
1338 log_debug(class, init)("Thread \"%s\" is initializing %s",
1339 jt->name(), external_name());
1340 }
1341 }
1342 }
1343
1344 // Pre-allocating an instance of the default value
1345 if (is_inline_klass()) {
1346 InlineKlass* vk = InlineKlass::cast(this);
1347 oop val = vk->allocate_instance(THREAD);
1348 if (HAS_PENDING_EXCEPTION) {
1349 Handle e(THREAD, PENDING_EXCEPTION);
1350 CLEAR_PENDING_EXCEPTION;
1351 {
1352 EXCEPTION_MARK;
1353 add_initialization_error(THREAD, e);
1354 // Locks object, set state, and notify all waiting threads
1355 set_initialization_state_and_notify(initialization_error, THREAD);
1356 CLEAR_PENDING_EXCEPTION;
1357 }
1358 THROW_OOP(e());
1359 }
1360 vk->set_default_value(val);
1361 if (vk->has_nullable_layout()) {
1362 val = vk->allocate_instance(THREAD);
1363 if (HAS_PENDING_EXCEPTION) {
1364 Handle e(THREAD, PENDING_EXCEPTION);
1365 CLEAR_PENDING_EXCEPTION;
1366 {
1367 EXCEPTION_MARK;
1368 add_initialization_error(THREAD, e);
1369 // Locks object, set state, and notify all waiting threads
1370 set_initialization_state_and_notify(initialization_error, THREAD);
1371 CLEAR_PENDING_EXCEPTION;
1372 }
1373 THROW_OOP(e());
1374 }
1375 vk->set_null_reset_value(val);
1376 }
1377 }
1378
1379 // Step 7
1380 // Next, if C is a class rather than an interface, initialize it's super class and super
1381 // interfaces.
1382 if (!is_interface()) {
1383 Klass* super_klass = super();
1384 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1385 super_klass->initialize(THREAD);
1386 }
1387 // If C implements any interface that declares a non-static, concrete method,
1388 // the initialization of C triggers initialization of its super interfaces.
1389 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1390 // having a superinterface that declares, non-static, concrete methods
1391 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1392 initialize_super_interfaces(THREAD);
1393 }
1394
1395 // If any exceptions, complete abruptly, throwing the same exception as above.
1396 if (HAS_PENDING_EXCEPTION) {
1397 Handle e(THREAD, PENDING_EXCEPTION);
1398 CLEAR_PENDING_EXCEPTION;
1399 {
1400 EXCEPTION_MARK;
1401 add_initialization_error(THREAD, e);
1402 // Locks object, set state, and notify all waiting threads
1403 set_initialization_state_and_notify(initialization_error, THREAD);
1404 CLEAR_PENDING_EXCEPTION;
1405 }
1406 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1407 THROW_OOP(e());
1408 }
1409 }
1410
1411 // Step 8
1412 // Initialize classes of inline fields
1413 if (EnableValhalla) {
1414 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1415 if (fs.is_null_free_inline_type()) {
1416
1417 // inline type field klass array entries must have alreadyt been filed at load time or link time
1418 Klass* klass = get_inline_type_field_klass(fs.index());
1419
1420 InstanceKlass::cast(klass)->initialize(THREAD);
1421 if (fs.access_flags().is_static()) {
1422 if (java_mirror()->obj_field(fs.offset()) == nullptr) {
1423 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value());
1424 }
1425 }
1426
1427 if (HAS_PENDING_EXCEPTION) {
1428 Handle e(THREAD, PENDING_EXCEPTION);
1429 CLEAR_PENDING_EXCEPTION;
1430 {
1431 EXCEPTION_MARK;
1432 add_initialization_error(THREAD, e);
1433 // Locks object, set state, and notify all waiting threads
1434 set_initialization_state_and_notify(initialization_error, THREAD);
1435 CLEAR_PENDING_EXCEPTION;
1436 }
1437 THROW_OOP(e());
1438 }
1439 }
1440 }
1441 }
1442
1443
1444 // Step 9
1445 {
1446 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1447 if (class_initializer() != nullptr) {
1448 // Timer includes any side effects of class initialization (resolution,
1449 // etc), but not recursive entry into call_class_initializer().
1450 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1451 ClassLoader::perf_class_init_selftime(),
1452 ClassLoader::perf_classes_inited(),
1453 jt->get_thread_stat()->perf_recursion_counts_addr(),
1454 jt->get_thread_stat()->perf_timers_addr(),
1455 PerfClassTraceTime::CLASS_CLINIT);
1456 call_class_initializer(THREAD);
1457 } else {
1458 // The elapsed time is so small it's not worth counting.
1459 if (UsePerfData) {
1460 ClassLoader::perf_classes_inited()->inc();
1461 }
1462 call_class_initializer(THREAD);
1463 }
1464 }
1465
1466 // Step 10
1467 if (!HAS_PENDING_EXCEPTION) {
1468 set_initialization_state_and_notify(fully_initialized, CHECK);
1469 debug_only(vtable().verify(tty, true);)
1470 }
1471 else {
1472 // Step 11 and 12
1473 Handle e(THREAD, PENDING_EXCEPTION);
1474 CLEAR_PENDING_EXCEPTION;
1475 // JVMTI has already reported the pending exception
1476 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1477 JvmtiExport::clear_detected_exception(jt);
1478 {
1479 EXCEPTION_MARK;
1480 add_initialization_error(THREAD, e);
1481 set_initialization_state_and_notify(initialization_error, THREAD);
1482 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1483 // JVMTI has already reported the pending exception
1484 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1485 JvmtiExport::clear_detected_exception(jt);
1486 }
1487 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1488 if (e->is_a(vmClasses::Error_klass())) {
1489 THROW_OOP(e());
1490 } else {
1491 JavaCallArguments args(e);
1492 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1493 vmSymbols::throwable_void_signature(),
1494 &args);
1495 }
1496 }
1497 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1498 }
1499
1500
1501 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1502 Handle h_init_lock(THREAD, init_lock());
1503 if (h_init_lock() != nullptr) {
1504 ObjectLocker ol(h_init_lock, THREAD);
1505 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1506 set_init_state(state);
1507 fence_and_clear_init_lock();
1508 ol.notify_all(CHECK);
1509 } else {
1510 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1511 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1512 set_init_state(state);
1513 }
1514 }
1515
1516 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1517 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1518 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1519 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1520
1521 DeoptimizationScope deopt_scope;
1522 {
1523 MutexLocker ml(current, Compile_lock);
1524
1525 set_init_state(InstanceKlass::loaded);
1526 // make sure init_state store is already done.
1527 // The compiler reads the hierarchy outside of the Compile_lock.
1528 // Access ordering is used to add to hierarchy.
1529
1530 // Link into hierarchy.
1531 append_to_sibling_list(); // add to superklass/sibling list
1532 process_interfaces(); // handle all "implements" declarations
1533
1534 // Now mark all code that depended on old class hierarchy.
1535 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1536 if (Universe::is_fully_initialized()) {
1537 CodeCache::mark_dependents_on(&deopt_scope, this);
1538 }
1539 }
1540 // Perform the deopt handshake outside Compile_lock.
1541 deopt_scope.deoptimize_marked();
1542 }
1543
1544
1545 InstanceKlass* InstanceKlass::implementor() const {
1546 InstanceKlass* volatile* ik = adr_implementor();
1547 if (ik == nullptr) {
1548 return nullptr;
1549 } else {
1550 // This load races with inserts, and therefore needs acquire.
1551 InstanceKlass* ikls = Atomic::load_acquire(ik);
1552 if (ikls != nullptr && !ikls->is_loader_alive()) {
1553 return nullptr; // don't return unloaded class
1554 } else {
1555 return ikls;
1556 }
1557 }
1558 }
1559
1560
1561 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1562 assert_locked_or_safepoint(Compile_lock);
1563 assert(is_interface(), "not interface");
1564 InstanceKlass* volatile* addr = adr_implementor();
1565 assert(addr != nullptr, "null addr");
1566 if (addr != nullptr) {
1567 Atomic::release_store(addr, ik);
1568 }
1569 }
1570
1571 int InstanceKlass::nof_implementors() const {
1572 InstanceKlass* ik = implementor();
1573 if (ik == nullptr) {
1574 return 0;
1575 } else if (ik != this) {
1576 return 1;
1577 } else {
1578 return 2;
1579 }
1580 }
1581
1582 // The embedded _implementor field can only record one implementor.
1583 // When there are more than one implementors, the _implementor field
1584 // is set to the interface Klass* itself. Following are the possible
1585 // values for the _implementor field:
1586 // null - no implementor
1587 // implementor Klass* - one implementor
1588 // self - more than one implementor
1589 //
1590 // The _implementor field only exists for interfaces.
1591 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1592 if (Universe::is_fully_initialized()) {
1593 assert_lock_strong(Compile_lock);
1594 }
1595 assert(is_interface(), "not interface");
1596 // Filter out my subinterfaces.
1597 // (Note: Interfaces are never on the subklass list.)
1598 if (ik->is_interface()) return;
1599
1600 // Filter out subclasses whose supers already implement me.
1601 // (Note: CHA must walk subclasses of direct implementors
1602 // in order to locate indirect implementors.)
1603 InstanceKlass* super_ik = ik->java_super();
1604 if (super_ik != nullptr && super_ik->implements_interface(this))
1605 // We only need to check one immediate superclass, since the
1606 // implements_interface query looks at transitive_interfaces.
1607 // Any supers of the super have the same (or fewer) transitive_interfaces.
1608 return;
1609
1610 InstanceKlass* iklass = implementor();
1611 if (iklass == nullptr) {
1612 set_implementor(ik);
1613 } else if (iklass != this && iklass != ik) {
1614 // There is already an implementor. Use itself as an indicator of
1615 // more than one implementors.
1616 set_implementor(this);
1617 }
1618
1619 // The implementor also implements the transitive_interfaces
1620 for (int index = 0; index < local_interfaces()->length(); index++) {
1621 local_interfaces()->at(index)->add_implementor(ik);
1622 }
1623 }
1624
1625 void InstanceKlass::init_implementor() {
1626 if (is_interface()) {
1627 set_implementor(nullptr);
1628 }
1629 }
1630
1631
1632 void InstanceKlass::process_interfaces() {
1633 // link this class into the implementors list of every interface it implements
1634 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1635 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1636 InstanceKlass* interf = local_interfaces()->at(i);
1637 assert(interf->is_interface(), "expected interface");
1638 interf->add_implementor(this);
1639 }
1640 }
1641
1642 bool InstanceKlass::can_be_primary_super_slow() const {
1643 if (is_interface())
1644 return false;
1645 else
1646 return Klass::can_be_primary_super_slow();
1647 }
1648
1649 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1650 Array<InstanceKlass*>* transitive_interfaces) {
1651 // The secondaries are the implemented interfaces.
1652 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1653 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1654 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1655 int num_secondaries = num_extra_slots + interfaces->length();
1656 if (num_secondaries == 0) {
1657 // Must share this for correct bootstrapping!
1658 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1659 return nullptr;
1660 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1661 // We will reuse the transitive interfaces list if we're certain
1662 // it's in hash order.
1663 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1664 set_secondary_supers(interfaces, bitmap);
1665 return nullptr;
1666 }
1667 // Copy transitive interfaces to a temporary growable array to be constructed
1668 // into the secondary super list with extra slots.
1669 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1670 for (int i = 0; i < interfaces->length(); i++) {
1671 secondaries->push(interfaces->at(i));
1672 }
1673 return secondaries;
1674 }
1675
1676 bool InstanceKlass::implements_interface(Klass* k) const {
1677 if (this == k) return true;
1678 assert(k->is_interface(), "should be an interface class");
1679 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1680 if (transitive_interfaces()->at(i) == k) {
1681 return true;
1682 }
1683 }
1684 return false;
1685 }
1686
1687 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1688 // Verify direct super interface
1689 if (this == k) return true;
1690 assert(k->is_interface(), "should be an interface class");
1691 for (int i = 0; i < local_interfaces()->length(); i++) {
1692 if (local_interfaces()->at(i) == k) {
1693 return true;
1694 }
1695 }
1696 return false;
1697 }
1698
1699 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1700 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1701 size_t size = objArrayOopDesc::object_size(length);
1702 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1703 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1704 /* do_zero */ true, CHECK_NULL);
1705 return o;
1706 }
1707
1708 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1709 if (TraceFinalizerRegistration) {
1710 tty->print("Registered ");
1711 i->print_value_on(tty);
1712 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1713 }
1714 instanceHandle h_i(THREAD, i);
1715 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1716 JavaValue result(T_VOID);
1717 JavaCallArguments args(h_i);
1718 methodHandle mh(THREAD, Universe::finalizer_register_method());
1719 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1720 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1721 return h_i();
1722 }
1723
1724 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1725 assert(!is_abstract() && !is_interface(), "Should not create this object");
1726 size_t size = size_helper(); // Query before forming handle.
1727 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1728 }
1729
1730 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1731 Klass* k = java_lang_Class::as_Klass(java_class);
1732 if (k == nullptr) {
1733 ResourceMark rm(THREAD);
1734 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1735 }
1736 InstanceKlass* ik = cast(k);
1737 ik->check_valid_for_instantiation(false, CHECK_NULL);
1738 ik->initialize(CHECK_NULL);
1739 return ik->allocate_instance(THREAD);
1740 }
1741
1742 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1743 return instanceHandle(THREAD, allocate_instance(THREAD));
1744 }
1745
1746 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1747 if (is_interface() || is_abstract()) {
1748 ResourceMark rm(THREAD);
1749 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1750 : vmSymbols::java_lang_InstantiationException(), external_name());
1751 }
1752 if (this == vmClasses::Class_klass()) {
1753 ResourceMark rm(THREAD);
1754 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1755 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1756 }
1757 }
1758
1759 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1760 // Need load-acquire for lock-free read
1761 if (array_klasses_acquire() == nullptr) {
1762
1763 // Recursively lock array allocation
1764 RecursiveLocker rl(MultiArray_lock, THREAD);
1765
1766 // Check if another thread created the array klass while we were waiting for the lock.
1767 if (array_klasses() == nullptr) {
1768 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, false, CHECK_NULL);
1769 // use 'release' to pair with lock-free load
1770 release_set_array_klasses(k);
1771 }
1772 }
1773
1774 // array_klasses() will always be set at this point
1775 ArrayKlass* ak = array_klasses();
1776 assert(ak != nullptr, "should be set");
1777 return ak->array_klass(n, THREAD);
1778 }
1779
1780 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1781 // Need load-acquire for lock-free read
1782 ArrayKlass* ak = array_klasses_acquire();
1783 if (ak == nullptr) {
1784 return nullptr;
1785 } else {
1786 return ak->array_klass_or_null(n);
1787 }
1788 }
1789
1790 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1791 return array_klass(1, THREAD);
1792 }
1793
1794 ArrayKlass* InstanceKlass::array_klass_or_null() {
1795 return array_klass_or_null(1);
1796 }
1797
1798 static int call_class_initializer_counter = 0; // for debugging
1799
1800 Method* InstanceKlass::class_initializer() const {
1801 Method* clinit = find_method(
1802 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1803 if (clinit != nullptr && clinit->is_class_initializer()) {
1804 return clinit;
1805 }
1806 return nullptr;
1807 }
1808
1809 void InstanceKlass::call_class_initializer(TRAPS) {
1810 if (ReplayCompiles &&
1811 (ReplaySuppressInitializers == 1 ||
1812 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1813 // Hide the existence of the initializer for the purpose of replaying the compile
1814 return;
1815 }
1816
1817 #if INCLUDE_CDS
1818 // This is needed to ensure the consistency of the archived heap objects.
1819 if (has_archived_enum_objs()) {
1820 assert(is_shared(), "must be");
1821 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1822 if (initialized) {
1823 return;
1824 }
1825 }
1826 #endif
1827
1828 methodHandle h_method(THREAD, class_initializer());
1829 assert(!is_initialized(), "we cannot initialize twice");
1830 LogTarget(Info, class, init) lt;
1831 if (lt.is_enabled()) {
1832 ResourceMark rm(THREAD);
1833 LogStream ls(lt);
1834 ls.print("%d Initializing ", call_class_initializer_counter++);
1835 name()->print_value_on(&ls);
1836 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1837 h_method() == nullptr ? "(no method)" : "", p2i(this),
1838 THREAD->name());
1839 }
1840 if (h_method() != nullptr) {
1841 JavaCallArguments args; // No arguments
1842 JavaValue result(T_VOID);
1843 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1844 }
1845 }
1846
1847
1848 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1849 InterpreterOopMap* entry_for) {
1850 // Lazily create the _oop_map_cache at first request.
1851 // Load_acquire is needed to safely get instance published with CAS by another thread.
1852 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1853 if (oop_map_cache == nullptr) {
1854 // Try to install new instance atomically.
1855 oop_map_cache = new OopMapCache();
1856 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1857 if (other != nullptr) {
1858 // Someone else managed to install before us, ditch local copy and use the existing one.
1859 delete oop_map_cache;
1860 oop_map_cache = other;
1861 }
1862 }
1863 // _oop_map_cache is constant after init; lookup below does its own locking.
1864 oop_map_cache->lookup(method, bci, entry_for);
1865 }
1866
1867
1868 FieldInfo InstanceKlass::field(int index) const {
1869 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1870 if (fs.index() == index) {
1871 return fs.to_FieldInfo();
1872 }
1873 }
1874 fatal("Field not found");
1875 return FieldInfo();
1876 }
1877
1878 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1879 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1880 Symbol* f_name = fs.name();
1881 Symbol* f_sig = fs.signature();
1882 if (f_name == name && f_sig == sig) {
1883 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1884 return true;
1885 }
1886 }
1887 return false;
1888 }
1889
1890
1891 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1892 const int n = local_interfaces()->length();
1893 for (int i = 0; i < n; i++) {
1894 Klass* intf1 = local_interfaces()->at(i);
1895 assert(intf1->is_interface(), "just checking type");
1896 // search for field in current interface
1897 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1898 assert(fd->is_static(), "interface field must be static");
1899 return intf1;
1900 }
1901 // search for field in direct superinterfaces
1902 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1903 if (intf2 != nullptr) return intf2;
1904 }
1905 // otherwise field lookup fails
1906 return nullptr;
1907 }
1908
1909
1910 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1911 // search order according to newest JVM spec (5.4.3.2, p.167).
1912 // 1) search for field in current klass
1913 if (find_local_field(name, sig, fd)) {
1914 return const_cast<InstanceKlass*>(this);
1915 }
1916 // 2) search for field recursively in direct superinterfaces
1917 { Klass* intf = find_interface_field(name, sig, fd);
1918 if (intf != nullptr) return intf;
1919 }
1920 // 3) apply field lookup recursively if superclass exists
1921 { Klass* supr = super();
1922 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1923 }
1924 // 4) otherwise field lookup fails
1925 return nullptr;
1926 }
1927
1928
1929 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1930 // search order according to newest JVM spec (5.4.3.2, p.167).
1931 // 1) search for field in current klass
1932 if (find_local_field(name, sig, fd)) {
1933 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1934 }
1935 // 2) search for field recursively in direct superinterfaces
1936 if (is_static) {
1937 Klass* intf = find_interface_field(name, sig, fd);
1938 if (intf != nullptr) return intf;
1939 }
1940 // 3) apply field lookup recursively if superclass exists
1941 { Klass* supr = super();
1942 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1943 }
1944 // 4) otherwise field lookup fails
1945 return nullptr;
1946 }
1947
1948 bool InstanceKlass::contains_field_offset(int offset) {
1949 if (this->is_inline_klass()) {
1950 InlineKlass* vk = InlineKlass::cast(this);
1951 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->payload_size_in_bytes());
1952 } else {
1953 fieldDescriptor fd;
1954 return find_field_from_offset(offset, false, &fd);
1955 }
1956 }
1957
1958 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1959 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1960 if (fs.offset() == offset) {
1961 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1962 if (fd->is_static() == is_static) return true;
1963 }
1964 }
1965 return false;
1966 }
1967
1968
1969 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1970 Klass* klass = const_cast<InstanceKlass*>(this);
1971 while (klass != nullptr) {
1972 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1973 return true;
1974 }
1975 klass = klass->super();
1976 }
1977 return false;
1978 }
1979
1980
1981 void InstanceKlass::methods_do(void f(Method* method)) {
1982 // Methods aren't stable until they are loaded. This can be read outside
1983 // a lock through the ClassLoaderData for profiling
1984 // Redefined scratch classes are on the list and need to be cleaned
1985 if (!is_loaded() && !is_scratch_class()) {
1986 return;
1987 }
1988
1989 int len = methods()->length();
1990 for (int index = 0; index < len; index++) {
1991 Method* m = methods()->at(index);
1992 assert(m->is_method(), "must be method");
1993 f(m);
1994 }
1995 }
1996
1997
1998 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1999 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2000 if (fs.access_flags().is_static()) {
2001 fieldDescriptor& fd = fs.field_descriptor();
2002 cl->do_field(&fd);
2003 }
2004 }
2005 }
2006
2007
2008 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2009 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2010 if (fs.access_flags().is_static()) {
2011 fieldDescriptor& fd = fs.field_descriptor();
2012 f(&fd, mirror, CHECK);
2013 }
2014 }
2015 }
2016
2017 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2018 InstanceKlass* super = superklass();
2019 if (super != nullptr) {
2020 super->do_nonstatic_fields(cl);
2021 }
2022 fieldDescriptor fd;
2023 int length = java_fields_count();
2024 for (int i = 0; i < length; i += 1) {
2025 fd.reinitialize(this, i);
2026 if (!fd.is_static()) {
2027 cl->do_field(&fd);
2028 }
2029 }
2030 }
2031
2032 // first in Pair is offset, second is index.
2033 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2034 return a->first - b->first;
2035 }
2036
2037 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2038 InstanceKlass* super = superklass();
2039 if (super != nullptr) {
2040 super->print_nonstatic_fields(cl);
2041 }
2042 ResourceMark rm;
2043 fieldDescriptor fd;
2044 // In DebugInfo nonstatic fields are sorted by offset.
2045 GrowableArray<Pair<int,int> > fields_sorted;
2046 int i = 0;
2047 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2048 if (!fs.access_flags().is_static()) {
2049 fd = fs.field_descriptor();
2050 Pair<int,int> f(fs.offset(), fs.index());
2051 fields_sorted.push(f);
2052 i++;
2053 }
2054 }
2055 if (i > 0) {
2056 int length = i;
2057 assert(length == fields_sorted.length(), "duh");
2058 fields_sorted.sort(compare_fields_by_offset);
2059 for (int i = 0; i < length; i++) {
2060 fd.reinitialize(this, fields_sorted.at(i).second);
2061 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2062 cl->do_field(&fd);
2063 }
2064 }
2065 }
2066
2067 #ifdef ASSERT
2068 static int linear_search(const Array<Method*>* methods,
2069 const Symbol* name,
2070 const Symbol* signature) {
2071 const int len = methods->length();
2072 for (int index = 0; index < len; index++) {
2073 const Method* const m = methods->at(index);
2074 assert(m->is_method(), "must be method");
2075 if (m->signature() == signature && m->name() == name) {
2076 return index;
2077 }
2078 }
2079 return -1;
2080 }
2081 #endif
2082
2083 bool InstanceKlass::_disable_method_binary_search = false;
2084
2085 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2086 int len = methods->length();
2087 int l = 0;
2088 int h = len - 1;
2089 while (l <= h) {
2090 Method* m = methods->at(l);
2091 if (m->name() == name) {
2092 return l;
2093 }
2094 l++;
2095 }
2096 return -1;
2097 }
2098
2099 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2100 if (_disable_method_binary_search) {
2101 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2102 // At the final stage of dynamic dumping, the methods array may not be sorted
2103 // by ascending addresses of their names, so we can't use binary search anymore.
2104 // However, methods with the same name are still laid out consecutively inside the
2105 // methods array, so let's look for the first one that matches.
2106 return linear_search(methods, name);
2107 }
2108
2109 int len = methods->length();
2110 int l = 0;
2111 int h = len - 1;
2112
2113 // methods are sorted by ascending addresses of their names, so do binary search
2114 while (l <= h) {
2115 int mid = (l + h) >> 1;
2116 Method* m = methods->at(mid);
2117 assert(m->is_method(), "must be method");
2118 int res = m->name()->fast_compare(name);
2119 if (res == 0) {
2120 return mid;
2121 } else if (res < 0) {
2122 l = mid + 1;
2123 } else {
2124 h = mid - 1;
2125 }
2126 }
2127 return -1;
2128 }
2129
2130 // find_method looks up the name/signature in the local methods array
2131 Method* InstanceKlass::find_method(const Symbol* name,
2132 const Symbol* signature) const {
2133 return find_method_impl(name, signature,
2134 OverpassLookupMode::find,
2135 StaticLookupMode::find,
2136 PrivateLookupMode::find);
2137 }
2138
2139 Method* InstanceKlass::find_method_impl(const Symbol* name,
2140 const Symbol* signature,
2141 OverpassLookupMode overpass_mode,
2142 StaticLookupMode static_mode,
2143 PrivateLookupMode private_mode) const {
2144 return InstanceKlass::find_method_impl(methods(),
2145 name,
2146 signature,
2147 overpass_mode,
2148 static_mode,
2149 private_mode);
2150 }
2151
2152 // find_instance_method looks up the name/signature in the local methods array
2153 // and skips over static methods
2154 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2155 const Symbol* name,
2156 const Symbol* signature,
2157 PrivateLookupMode private_mode) {
2158 Method* const meth = InstanceKlass::find_method_impl(methods,
2159 name,
2160 signature,
2161 OverpassLookupMode::find,
2162 StaticLookupMode::skip,
2163 private_mode);
2164 assert(((meth == nullptr) || !meth->is_static()),
2165 "find_instance_method should have skipped statics");
2166 return meth;
2167 }
2168
2169 // find_instance_method looks up the name/signature in the local methods array
2170 // and skips over static methods
2171 Method* InstanceKlass::find_instance_method(const Symbol* name,
2172 const Symbol* signature,
2173 PrivateLookupMode private_mode) const {
2174 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2175 }
2176
2177 // Find looks up the name/signature in the local methods array
2178 // and filters on the overpass, static and private flags
2179 // This returns the first one found
2180 // note that the local methods array can have up to one overpass, one static
2181 // and one instance (private or not) with the same name/signature
2182 Method* InstanceKlass::find_local_method(const Symbol* name,
2183 const Symbol* signature,
2184 OverpassLookupMode overpass_mode,
2185 StaticLookupMode static_mode,
2186 PrivateLookupMode private_mode) const {
2187 return InstanceKlass::find_method_impl(methods(),
2188 name,
2189 signature,
2190 overpass_mode,
2191 static_mode,
2192 private_mode);
2193 }
2194
2195 // Find looks up the name/signature in the local methods array
2196 // and filters on the overpass, static and private flags
2197 // This returns the first one found
2198 // note that the local methods array can have up to one overpass, one static
2199 // and one instance (private or not) with the same name/signature
2200 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2201 const Symbol* name,
2202 const Symbol* signature,
2203 OverpassLookupMode overpass_mode,
2204 StaticLookupMode static_mode,
2205 PrivateLookupMode private_mode) {
2206 return InstanceKlass::find_method_impl(methods,
2207 name,
2208 signature,
2209 overpass_mode,
2210 static_mode,
2211 private_mode);
2212 }
2213
2214 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2215 const Symbol* name,
2216 const Symbol* signature) {
2217 return InstanceKlass::find_method_impl(methods,
2218 name,
2219 signature,
2220 OverpassLookupMode::find,
2221 StaticLookupMode::find,
2222 PrivateLookupMode::find);
2223 }
2224
2225 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2226 const Symbol* name,
2227 const Symbol* signature,
2228 OverpassLookupMode overpass_mode,
2229 StaticLookupMode static_mode,
2230 PrivateLookupMode private_mode) {
2231 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2232 return hit >= 0 ? methods->at(hit): nullptr;
2233 }
2234
2235 // true if method matches signature and conforms to skipping_X conditions.
2236 static bool method_matches(const Method* m,
2237 const Symbol* signature,
2238 bool skipping_overpass,
2239 bool skipping_static,
2240 bool skipping_private) {
2241 return ((m->signature() == signature) &&
2242 (!skipping_overpass || !m->is_overpass()) &&
2243 (!skipping_static || !m->is_static()) &&
2244 (!skipping_private || !m->is_private()));
2245 }
2246
2247 // Used directly for default_methods to find the index into the
2248 // default_vtable_indices, and indirectly by find_method
2249 // find_method_index looks in the local methods array to return the index
2250 // of the matching name/signature. If, overpass methods are being ignored,
2251 // the search continues to find a potential non-overpass match. This capability
2252 // is important during method resolution to prefer a static method, for example,
2253 // over an overpass method.
2254 // There is the possibility in any _method's array to have the same name/signature
2255 // for a static method, an overpass method and a local instance method
2256 // To correctly catch a given method, the search criteria may need
2257 // to explicitly skip the other two. For local instance methods, it
2258 // is often necessary to skip private methods
2259 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2260 const Symbol* name,
2261 const Symbol* signature,
2262 OverpassLookupMode overpass_mode,
2263 StaticLookupMode static_mode,
2264 PrivateLookupMode private_mode) {
2265 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2266 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2267 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2268 const int hit = quick_search(methods, name);
2269 if (hit != -1) {
2270 const Method* const m = methods->at(hit);
2271
2272 // Do linear search to find matching signature. First, quick check
2273 // for common case, ignoring overpasses if requested.
2274 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2275 return hit;
2276 }
2277
2278 // search downwards through overloaded methods
2279 int i;
2280 for (i = hit - 1; i >= 0; --i) {
2281 const Method* const m = methods->at(i);
2282 assert(m->is_method(), "must be method");
2283 if (m->name() != name) {
2284 break;
2285 }
2286 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2287 return i;
2288 }
2289 }
2290 // search upwards
2291 for (i = hit + 1; i < methods->length(); ++i) {
2292 const Method* const m = methods->at(i);
2293 assert(m->is_method(), "must be method");
2294 if (m->name() != name) {
2295 break;
2296 }
2297 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2298 return i;
2299 }
2300 }
2301 // not found
2302 #ifdef ASSERT
2303 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2304 linear_search(methods, name, signature);
2305 assert(-1 == index, "binary search should have found entry %d", index);
2306 #endif
2307 }
2308 return -1;
2309 }
2310
2311 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2312 return find_method_by_name(methods(), name, end);
2313 }
2314
2315 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2316 const Symbol* name,
2317 int* end_ptr) {
2318 assert(end_ptr != nullptr, "just checking");
2319 int start = quick_search(methods, name);
2320 int end = start + 1;
2321 if (start != -1) {
2322 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2323 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2324 *end_ptr = end;
2325 return start;
2326 }
2327 return -1;
2328 }
2329
2330 // uncached_lookup_method searches both the local class methods array and all
2331 // superclasses methods arrays, skipping any overpass methods in superclasses,
2332 // and possibly skipping private methods.
2333 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2334 const Symbol* signature,
2335 OverpassLookupMode overpass_mode,
2336 PrivateLookupMode private_mode) const {
2337 OverpassLookupMode overpass_local_mode = overpass_mode;
2338 const Klass* klass = this;
2339 while (klass != nullptr) {
2340 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2341 signature,
2342 overpass_local_mode,
2343 StaticLookupMode::find,
2344 private_mode);
2345 if (method != nullptr) {
2346 return method;
2347 }
2348 if (name == vmSymbols::object_initializer_name()) {
2349 break; // <init> is never inherited
2350 }
2351 klass = klass->super();
2352 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2353 }
2354 return nullptr;
2355 }
2356
2357 #ifdef ASSERT
2358 // search through class hierarchy and return true if this class or
2359 // one of the superclasses was redefined
2360 bool InstanceKlass::has_redefined_this_or_super() const {
2361 const Klass* klass = this;
2362 while (klass != nullptr) {
2363 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2364 return true;
2365 }
2366 klass = klass->super();
2367 }
2368 return false;
2369 }
2370 #endif
2371
2372 // lookup a method in the default methods list then in all transitive interfaces
2373 // Do NOT return private or static methods
2374 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2375 Symbol* signature) const {
2376 Method* m = nullptr;
2377 if (default_methods() != nullptr) {
2378 m = find_method(default_methods(), name, signature);
2379 }
2380 // Look up interfaces
2381 if (m == nullptr) {
2382 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2383 }
2384 return m;
2385 }
2386
2387 // lookup a method in all the interfaces that this class implements
2388 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2389 // They should only be found in the initial InterfaceMethodRef
2390 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2391 Symbol* signature,
2392 DefaultsLookupMode defaults_mode) const {
2393 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2394 int num_ifs = all_ifs->length();
2395 InstanceKlass *ik = nullptr;
2396 for (int i = 0; i < num_ifs; i++) {
2397 ik = all_ifs->at(i);
2398 Method* m = ik->lookup_method(name, signature);
2399 if (m != nullptr && m->is_public() && !m->is_static() &&
2400 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2401 return m;
2402 }
2403 }
2404 return nullptr;
2405 }
2406
2407 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2408 :_st(st), _verbose(verbose) {
2409 ResourceMark rm;
2410 _st->print("%-18s ", "KlassAddr");
2411 _st->print("%-4s ", "Size");
2412 _st->print("%-20s ", "State");
2413 _st->print("%-7s ", "Flags");
2414 _st->print("%-5s ", "ClassName");
2415 _st->cr();
2416 }
2417
2418 void PrintClassClosure::do_klass(Klass* k) {
2419 ResourceMark rm;
2420 // klass pointer
2421 _st->print(PTR_FORMAT " ", p2i(k));
2422 // klass size
2423 _st->print("%4d ", k->size());
2424 // initialization state
2425 if (k->is_instance_klass()) {
2426 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2427 } else {
2428 _st->print("%-20s ","");
2429 }
2430 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2431 char buf[10];
2432 int i = 0;
2433 if (k->has_finalizer()) buf[i++] = 'F';
2434 if (k->is_instance_klass()) {
2435 InstanceKlass* ik = InstanceKlass::cast(k);
2436 if (ik->has_final_method()) buf[i++] = 'f';
2437 if (ik->is_rewritten()) buf[i++] = 'W';
2438 if (ik->is_contended()) buf[i++] = 'C';
2439 if (ik->has_been_redefined()) buf[i++] = 'R';
2440 if (ik->is_shared()) buf[i++] = 'S';
2441 }
2442 buf[i++] = '\0';
2443 _st->print("%-7s ", buf);
2444 // klass name
2445 _st->print("%-5s ", k->external_name());
2446 // end
2447 _st->cr();
2448 if (_verbose) {
2449 k->print_on(_st);
2450 }
2451 }
2452
2453 /* jni_id_for for jfieldIds only */
2454 JNIid* InstanceKlass::jni_id_for(int offset) {
2455 MutexLocker ml(JfieldIdCreation_lock);
2456 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2457 if (probe == nullptr) {
2458 // Allocate new static field identifier
2459 probe = new JNIid(this, offset, jni_ids());
2460 set_jni_ids(probe);
2461 }
2462 return probe;
2463 }
2464
2465 u2 InstanceKlass::enclosing_method_data(int offset) const {
2466 const Array<jushort>* const inner_class_list = inner_classes();
2467 if (inner_class_list == nullptr) {
2468 return 0;
2469 }
2470 const int length = inner_class_list->length();
2471 if (length % inner_class_next_offset == 0) {
2472 return 0;
2473 }
2474 const int index = length - enclosing_method_attribute_size;
2475 assert(offset < enclosing_method_attribute_size, "invalid offset");
2476 return inner_class_list->at(index + offset);
2477 }
2478
2479 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2480 u2 method_index) {
2481 Array<jushort>* inner_class_list = inner_classes();
2482 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2483 int length = inner_class_list->length();
2484 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2485 int index = length - enclosing_method_attribute_size;
2486 inner_class_list->at_put(
2487 index + enclosing_method_class_index_offset, class_index);
2488 inner_class_list->at_put(
2489 index + enclosing_method_method_index_offset, method_index);
2490 }
2491 }
2492
2493 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2494 if (method->is_old() && !method->is_obsolete()) {
2495 // If the method passed in is old (but not obsolete), use the current version.
2496 method = method_with_idnum((int)idnum);
2497 assert(method != nullptr, "old and but not obsolete, so should exist");
2498 }
2499 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2500 Atomic::release_store(&jmeths[idnum + 1], new_id);
2501 return new_id;
2502 }
2503
2504 // Lookup or create a jmethodID.
2505 // This code is called by the VMThread and JavaThreads so the
2506 // locking has to be done very carefully to avoid deadlocks
2507 // and/or other cache consistency problems.
2508 //
2509 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2510 Method* method = method_h();
2511 int idnum = method->method_idnum();
2512 jmethodID* jmeths = methods_jmethod_ids_acquire();
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 // acquired in those two cases.
2525 //
2526 // If the RedefineClasses() API has been used, then this cache grows
2527 // in the redefinition safepoint.
2528
2529 if (jmeths == nullptr) {
2530 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2531 jmeths = methods_jmethod_ids_acquire();
2532 // Still null?
2533 if (jmeths == nullptr) {
2534 size_t size = idnum_allocated_count();
2535 assert(size > (size_t)idnum, "should already have space");
2536 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2537 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2538 // cache size is stored in element[0], other elements offset by one
2539 jmeths[0] = (jmethodID)size;
2540 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2541
2542 // publish jmeths
2543 release_set_methods_jmethod_ids(jmeths);
2544 return new_id;
2545 }
2546 }
2547
2548 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2549 if (id == nullptr) {
2550 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2551 id = jmeths[idnum + 1];
2552 // Still null?
2553 if (id == nullptr) {
2554 return update_jmethod_id(jmeths, method, idnum);
2555 }
2556 }
2557 return id;
2558 }
2559
2560 void InstanceKlass::update_methods_jmethod_cache() {
2561 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2562 jmethodID* cache = _methods_jmethod_ids;
2563 if (cache != nullptr) {
2564 size_t size = idnum_allocated_count();
2565 size_t old_size = (size_t)cache[0];
2566 if (old_size < size + 1) {
2567 // Allocate a larger one and copy entries to the new one.
2568 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2569 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2570 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2571 // The cache size is stored in element[0]; the other elements are offset by one.
2572 new_cache[0] = (jmethodID)size;
2573
2574 for (int i = 1; i <= (int)old_size; i++) {
2575 new_cache[i] = cache[i];
2576 }
2577 _methods_jmethod_ids = new_cache;
2578 FREE_C_HEAP_ARRAY(jmethodID, cache);
2579 }
2580 }
2581 }
2582
2583 // Figure out how many jmethodIDs haven't been allocated, and make
2584 // sure space for them is pre-allocated. This makes getting all
2585 // method ids much, much faster with classes with more than 8
2586 // methods, and has a *substantial* effect on performance with jvmti
2587 // code that loads all jmethodIDs for all classes.
2588 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2589 int new_jmeths = 0;
2590 int length = methods()->length();
2591 for (int index = start_offset; index < length; index++) {
2592 Method* m = methods()->at(index);
2593 jmethodID id = m->find_jmethod_id_or_null();
2594 if (id == nullptr) {
2595 new_jmeths++;
2596 }
2597 }
2598 if (new_jmeths != 0) {
2599 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2600 }
2601 }
2602
2603 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2604 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2605 int idnum = method->method_idnum();
2606 jmethodID* jmeths = methods_jmethod_ids_acquire();
2607 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2608 }
2609
2610 inline DependencyContext InstanceKlass::dependencies() {
2611 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2612 return dep_context;
2613 }
2614
2615 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2616 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2617 }
2618
2619 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2620 dependencies().add_dependent_nmethod(nm);
2621 }
2622
2623 void InstanceKlass::clean_dependency_context() {
2624 dependencies().clean_unloading_dependents();
2625 }
2626
2627 #ifndef PRODUCT
2628 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2629 dependencies().print_dependent_nmethods(verbose);
2630 }
2631
2632 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2633 return dependencies().is_dependent_nmethod(nm);
2634 }
2635 #endif //PRODUCT
2636
2637 void InstanceKlass::clean_weak_instanceklass_links() {
2638 clean_implementors_list();
2639 clean_method_data();
2640 }
2641
2642 void InstanceKlass::clean_implementors_list() {
2643 assert(is_loader_alive(), "this klass should be live");
2644 if (is_interface()) {
2645 assert (ClassUnloading, "only called for ClassUnloading");
2646 for (;;) {
2647 // Use load_acquire due to competing with inserts
2648 InstanceKlass* volatile* iklass = adr_implementor();
2649 assert(iklass != nullptr, "Klass must not be null");
2650 InstanceKlass* impl = Atomic::load_acquire(iklass);
2651 if (impl != nullptr && !impl->is_loader_alive()) {
2652 // null this field, might be an unloaded instance klass or null
2653 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2654 // Successfully unlinking implementor.
2655 if (log_is_enabled(Trace, class, unload)) {
2656 ResourceMark rm;
2657 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2658 }
2659 return;
2660 }
2661 } else {
2662 return;
2663 }
2664 }
2665 }
2666 }
2667
2668 void InstanceKlass::clean_method_data() {
2669 for (int m = 0; m < methods()->length(); m++) {
2670 MethodData* mdo = methods()->at(m)->method_data();
2671 if (mdo != nullptr) {
2672 mdo->clean_method_data(/*always_clean*/false);
2673 }
2674 }
2675 }
2676
2677 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2678 Klass::metaspace_pointers_do(it);
2679
2680 if (log_is_enabled(Trace, cds)) {
2681 ResourceMark rm;
2682 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2683 }
2684
2685 it->push(&_annotations);
2686 it->push((Klass**)&_array_klasses);
2687 if (!is_rewritten()) {
2688 it->push(&_constants, MetaspaceClosure::_writable);
2689 } else {
2690 it->push(&_constants);
2691 }
2692 it->push(&_inner_classes);
2693 #if INCLUDE_JVMTI
2694 it->push(&_previous_versions);
2695 #endif
2696 #if INCLUDE_CDS
2697 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2698 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely
2699 // checked here with ByteCodeStream. All methods that can't be verified are made writable.
2700 // The length check on the _methods is necessary because classes which don't have any
2701 // methods share the Universe::_the_empty_method_array which is in the RO region.
2702 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) {
2703 // To handle jsr bytecode, new Method* maybe stored into _methods
2704 it->push(&_methods, MetaspaceClosure::_writable);
2705 } else {
2706 #endif
2707 it->push(&_methods);
2708 #if INCLUDE_CDS
2709 }
2710 #endif
2711 it->push(&_default_methods);
2712 it->push(&_local_interfaces);
2713 it->push(&_transitive_interfaces);
2714 it->push(&_method_ordering);
2715 if (!is_rewritten()) {
2716 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2717 } else {
2718 it->push(&_default_vtable_indices);
2719 }
2720
2721 it->push(&_fieldinfo_stream);
2722 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2723 it->push(&_fields_status, MetaspaceClosure::_writable);
2724
2725 if (itable_length() > 0) {
2726 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2727 int method_table_offset_in_words = ioe->offset()/wordSize;
2728 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2729
2730 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2731 / itableOffsetEntry::size();
2732
2733 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2734 if (ioe->interface_klass() != nullptr) {
2735 it->push(ioe->interface_klass_addr());
2736 itableMethodEntry* ime = ioe->first_method_entry(this);
2737 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2738 for (int index = 0; index < n; index ++) {
2739 it->push(ime[index].method_addr());
2740 }
2741 }
2742 }
2743 }
2744
2745 it->push(&_nest_members);
2746 it->push(&_permitted_subclasses);
2747 it->push(&_loadable_descriptors);
2748 it->push(&_record_components);
2749 it->push(&_inline_layout_info_array, MetaspaceClosure::_writable);
2750 }
2751
2752 #if INCLUDE_CDS
2753 void InstanceKlass::remove_unshareable_info() {
2754
2755 if (is_linked()) {
2756 assert(can_be_verified_at_dumptime(), "must be");
2757 // Remember this so we can avoid walking the hierarchy at runtime.
2758 set_verified_at_dump_time();
2759 }
2760
2761 Klass::remove_unshareable_info();
2762
2763 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2764 // Classes are attempted to link during dumping and may fail,
2765 // but these classes are still in the dictionary and class list in CLD.
2766 // If the class has failed verification, there is nothing else to remove.
2767 return;
2768 }
2769
2770 // Reset to the 'allocated' state to prevent any premature accessing to
2771 // a shared class at runtime while the class is still being loaded and
2772 // restored. A class' init_state is set to 'loaded' at runtime when it's
2773 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2774 _init_state = allocated;
2775
2776 { // Otherwise this needs to take out the Compile_lock.
2777 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2778 init_implementor();
2779 }
2780
2781 // Call remove_unshareable_info() on other objects that belong to this class, except
2782 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2783 // ArchiveBuilder::make_klasses_shareable(),
2784
2785 for (int i = 0; i < methods()->length(); i++) {
2786 Method* m = methods()->at(i);
2787 m->remove_unshareable_info();
2788 }
2789
2790 // do array classes also.
2791 if (array_klasses() != nullptr) {
2792 array_klasses()->remove_unshareable_info();
2793 }
2794
2795 // These are not allocated from metaspace. They are safe to set to nullptr.
2796 _source_debug_extension = nullptr;
2797 _dep_context = nullptr;
2798 _osr_nmethods_head = nullptr;
2799 #if INCLUDE_JVMTI
2800 _breakpoints = nullptr;
2801 _previous_versions = nullptr;
2802 _cached_class_file = nullptr;
2803 _jvmti_cached_class_field_map = nullptr;
2804 #endif
2805
2806 _init_thread = nullptr;
2807 _methods_jmethod_ids = nullptr;
2808 _jni_ids = nullptr;
2809 _oop_map_cache = nullptr;
2810 // clear _nest_host to ensure re-load at runtime
2811 _nest_host = nullptr;
2812 init_shared_package_entry();
2813 _dep_context_last_cleaned = 0;
2814
2815 remove_unshareable_flags();
2816 }
2817
2818 void InstanceKlass::remove_unshareable_flags() {
2819 // clear all the flags/stats that shouldn't be in the archived version
2820 assert(!is_scratch_class(), "must be");
2821 assert(!has_been_redefined(), "must be");
2822 #if INCLUDE_JVMTI
2823 set_is_being_redefined(false);
2824 #endif
2825 set_has_resolved_methods(false);
2826 }
2827
2828 void InstanceKlass::remove_java_mirror() {
2829 Klass::remove_java_mirror();
2830
2831 // do array classes also.
2832 if (array_klasses() != nullptr) {
2833 array_klasses()->remove_java_mirror();
2834 }
2835 }
2836
2837 void InstanceKlass::init_shared_package_entry() {
2838 assert(CDSConfig::is_dumping_archive(), "must be");
2839 #if !INCLUDE_CDS_JAVA_HEAP
2840 _package_entry = nullptr;
2841 #else
2842 if (CDSConfig::is_dumping_full_module_graph()) {
2843 if (is_shared_unregistered_class()) {
2844 _package_entry = nullptr;
2845 } else {
2846 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2847 }
2848 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2849 CDSConfig::is_using_full_module_graph() &&
2850 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2851 // _package_entry is an archived package in the base archive. Leave it as is.
2852 } else {
2853 _package_entry = nullptr;
2854 }
2855 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2856 #endif
2857 }
2858
2859 void InstanceKlass::compute_has_loops_flag_for_methods() {
2860 Array<Method*>* methods = this->methods();
2861 for (int index = 0; index < methods->length(); ++index) {
2862 Method* m = methods->at(index);
2863 if (!m->is_overpass()) { // work around JDK-8305771
2864 m->compute_has_loops_flag();
2865 }
2866 }
2867 }
2868
2869 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2870 PackageEntry* pkg_entry, TRAPS) {
2871 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2872 // before the InstanceKlass is added to the SystemDictionary. Make
2873 // sure the current state is <loaded.
2874 assert(!is_loaded(), "invalid init state");
2875 assert(!shared_loading_failed(), "Must not try to load failed class again");
2876 set_package(loader_data, pkg_entry, CHECK);
2877 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2878
2879 if (is_inline_klass()) {
2880 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2881 }
2882
2883 Array<Method*>* methods = this->methods();
2884 int num_methods = methods->length();
2885 for (int index = 0; index < num_methods; ++index) {
2886 methods->at(index)->restore_unshareable_info(CHECK);
2887 }
2888 #if INCLUDE_JVMTI
2889 if (JvmtiExport::has_redefined_a_class()) {
2890 // Reinitialize vtable because RedefineClasses may have changed some
2891 // entries in this vtable for super classes so the CDS vtable might
2892 // point to old or obsolete entries. RedefineClasses doesn't fix up
2893 // vtables in the shared system dictionary, only the main one.
2894 // It also redefines the itable too so fix that too.
2895 // First fix any default methods that point to a super class that may
2896 // have been redefined.
2897 bool trace_name_printed = false;
2898 adjust_default_methods(&trace_name_printed);
2899 vtable().initialize_vtable();
2900 itable().initialize_itable();
2901 }
2902 #endif
2903
2904 // restore constant pool resolved references
2905 constants()->restore_unshareable_info(CHECK);
2906
2907 if (array_klasses() != nullptr) {
2908 // To get a consistent list of classes we need MultiArray_lock to ensure
2909 // array classes aren't observed while they are being restored.
2910 RecursiveLocker rl(MultiArray_lock, THREAD);
2911 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
2912 // Array classes have null protection domain.
2913 // --> see ArrayKlass::complete_create_array_klass()
2914 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2915 }
2916
2917 // Initialize @ValueBased class annotation if not already set in the archived klass.
2918 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2919 set_is_value_based();
2920 }
2921 }
2922
2923 // Check if a class or any of its supertypes has a version older than 50.
2924 // CDS will not perform verification of old classes during dump time because
2925 // without changing the old verifier, the verification constraint cannot be
2926 // retrieved during dump time.
2927 // Verification of archived old classes will be performed during run time.
2928 bool InstanceKlass::can_be_verified_at_dumptime() const {
2929 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2930 // This is a class that was dumped into the base archive, so we know
2931 // it was verified at dump time.
2932 return true;
2933 }
2934 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2935 return false;
2936 }
2937 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2938 return false;
2939 }
2940 Array<InstanceKlass*>* interfaces = local_interfaces();
2941 int len = interfaces->length();
2942 for (int i = 0; i < len; i++) {
2943 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2944 return false;
2945 }
2946 }
2947 return true;
2948 }
2949 #endif // INCLUDE_CDS
2950
2951 #if INCLUDE_JVMTI
2952 static void clear_all_breakpoints(Method* m) {
2953 m->clear_all_breakpoints();
2954 }
2955 #endif
2956
2957 void InstanceKlass::unload_class(InstanceKlass* ik) {
2958
2959 if (ik->is_scratch_class()) {
2960 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2961 return;
2962 }
2963 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2964
2965 // Release dependencies.
2966 ik->dependencies().remove_all_dependents();
2967
2968 // notify the debugger
2969 if (JvmtiExport::should_post_class_unload()) {
2970 JvmtiExport::post_class_unload(ik);
2971 }
2972
2973 // notify ClassLoadingService of class unload
2974 ClassLoadingService::notify_class_unloaded(ik);
2975
2976 SystemDictionaryShared::handle_class_unloading(ik);
2977
2978 if (log_is_enabled(Info, class, unload)) {
2979 ResourceMark rm;
2980 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
2981 }
2982
2983 Events::log_class_unloading(Thread::current(), ik);
2984
2985 #if INCLUDE_JFR
2986 assert(ik != nullptr, "invariant");
2987 EventClassUnload event;
2988 event.set_unloadedClass(ik);
2989 event.set_definingClassLoader(ik->class_loader_data());
2990 event.commit();
2991 #endif
2992 }
2993
2994 static void method_release_C_heap_structures(Method* m) {
2995 m->release_C_heap_structures();
2996 }
2997
2998 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
2999 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3000 // Clean up C heap
3001 Klass::release_C_heap_structures();
3002
3003 // Deallocate and call destructors for MDO mutexes
3004 if (release_sub_metadata) {
3005 methods_do(method_release_C_heap_structures);
3006 }
3007
3008 // Deallocate oop map cache
3009 if (_oop_map_cache != nullptr) {
3010 delete _oop_map_cache;
3011 _oop_map_cache = nullptr;
3012 }
3013
3014 // Deallocate JNI identifiers for jfieldIDs
3015 JNIid::deallocate(jni_ids());
3016 set_jni_ids(nullptr);
3017
3018 jmethodID* jmeths = methods_jmethod_ids_acquire();
3019 if (jmeths != nullptr) {
3020 release_set_methods_jmethod_ids(nullptr);
3021 FreeHeap(jmeths);
3022 }
3023
3024 assert(_dep_context == nullptr,
3025 "dependencies should already be cleaned");
3026
3027 #if INCLUDE_JVMTI
3028 // Deallocate breakpoint records
3029 if (breakpoints() != nullptr) {
3030 methods_do(clear_all_breakpoints);
3031 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3032 }
3033
3034 // deallocate the cached class file
3035 if (_cached_class_file != nullptr) {
3036 os::free(_cached_class_file);
3037 _cached_class_file = nullptr;
3038 }
3039 #endif
3040
3041 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3042
3043 if (release_sub_metadata) {
3044 constants()->release_C_heap_structures();
3045 }
3046 }
3047
3048 // The constant pool is on stack if any of the methods are executing or
3049 // referenced by handles.
3050 bool InstanceKlass::on_stack() const {
3051 return _constants->on_stack();
3052 }
3053
3054 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3055 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3056 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3057
3058 // minor and major version numbers of class file
3059 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3060 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3061 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3062 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3063
3064 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3065 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3066 if (ik->constants()->version() == version) {
3067 return ik;
3068 }
3069 }
3070 return nullptr;
3071 }
3072
3073 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3074 if (array == nullptr) {
3075 _source_debug_extension = nullptr;
3076 } else {
3077 // Adding one to the attribute length in order to store a null terminator
3078 // character could cause an overflow because the attribute length is
3079 // already coded with an u4 in the classfile, but in practice, it's
3080 // unlikely to happen.
3081 assert((length+1) > length, "Overflow checking");
3082 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3083 for (int i = 0; i < length; i++) {
3084 sde[i] = array[i];
3085 }
3086 sde[length] = '\0';
3087 _source_debug_extension = sde;
3088 }
3089 }
3090
3091 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3092 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3093 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3094
3095 const char* InstanceKlass::signature_name() const {
3096 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3097 }
3098
3099 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3100 // Get the internal name as a c string
3101 const char* src = (const char*) (name()->as_C_string());
3102 const int src_length = (int)strlen(src);
3103
3104 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3105
3106 // Add L or Q as type indicator
3107 int dest_index = 0;
3108 dest[dest_index++] = c;
3109
3110 // Add the actual class name
3111 for (int src_index = 0; src_index < src_length; ) {
3112 dest[dest_index++] = src[src_index++];
3113 }
3114
3115 if (is_hidden()) { // Replace the last '+' with a '.'.
3116 for (int index = (int)src_length; index > 0; index--) {
3117 if (dest[index] == '+') {
3118 dest[index] = JVM_SIGNATURE_DOT;
3119 break;
3120 }
3121 }
3122 }
3123
3124 // Add the semicolon and the null
3125 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3126 dest[dest_index] = '\0';
3127 return dest;
3128 }
3129
3130 ModuleEntry* InstanceKlass::module() const {
3131 if (is_hidden() &&
3132 in_unnamed_package() &&
3133 class_loader_data()->has_class_mirror_holder()) {
3134 // For a non-strong hidden class defined to an unnamed package,
3135 // its (class held) CLD will not have an unnamed module created for it.
3136 // Two choices to find the correct ModuleEntry:
3137 // 1. If hidden class is within a nest, use nest host's module
3138 // 2. Find the unnamed module off from the class loader
3139 // For now option #2 is used since a nest host is not set until
3140 // after the instance class is created in jvm_lookup_define_class().
3141 if (class_loader_data()->is_boot_class_loader_data()) {
3142 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3143 } else {
3144 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3145 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3146 return java_lang_Module::module_entry(module);
3147 }
3148 }
3149
3150 // Class is in a named package
3151 if (!in_unnamed_package()) {
3152 return _package_entry->module();
3153 }
3154
3155 // Class is in an unnamed package, return its loader's unnamed module
3156 return class_loader_data()->unnamed_module();
3157 }
3158
3159 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3160
3161 // ensure java/ packages only loaded by boot or platform builtin loaders
3162 // not needed for shared class since CDS does not archive prohibited classes.
3163 if (!is_shared()) {
3164 check_prohibited_package(name(), loader_data, CHECK);
3165 }
3166
3167 if (is_shared() && _package_entry != nullptr) {
3168 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3169 // we can use the saved package
3170 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3171 return;
3172 } else {
3173 _package_entry = nullptr;
3174 }
3175 }
3176
3177 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3178 // it returns, so we need to decrement it when the current function exits.
3179 TempNewSymbol from_class_name =
3180 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3181
3182 Symbol* pkg_name;
3183 if (pkg_entry != nullptr) {
3184 pkg_name = pkg_entry->name();
3185 } else {
3186 pkg_name = from_class_name;
3187 }
3188
3189 if (pkg_name != nullptr && loader_data != nullptr) {
3190
3191 // Find in class loader's package entry table.
3192 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3193
3194 // If the package name is not found in the loader's package
3195 // entry table, it is an indication that the package has not
3196 // been defined. Consider it defined within the unnamed module.
3197 if (_package_entry == nullptr) {
3198
3199 if (!ModuleEntryTable::javabase_defined()) {
3200 // Before java.base is defined during bootstrapping, define all packages in
3201 // the java.base module. If a non-java.base package is erroneously placed
3202 // in the java.base module it will be caught later when java.base
3203 // is defined by ModuleEntryTable::verify_javabase_packages check.
3204 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3205 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3206 } else {
3207 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3208 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3209 }
3210
3211 // A package should have been successfully created
3212 DEBUG_ONLY(ResourceMark rm(THREAD));
3213 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3214 name()->as_C_string(), loader_data->loader_name_and_id());
3215 }
3216
3217 if (log_is_enabled(Debug, module)) {
3218 ResourceMark rm(THREAD);
3219 ModuleEntry* m = _package_entry->module();
3220 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3221 external_name(),
3222 pkg_name->as_C_string(),
3223 loader_data->loader_name_and_id(),
3224 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3225 }
3226 } else {
3227 ResourceMark rm(THREAD);
3228 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3229 external_name(),
3230 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3231 UNNAMED_MODULE);
3232 }
3233 }
3234
3235 // Function set_classpath_index ensures that for a non-null _package_entry
3236 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3237 // It then sets the classpath_index in the package entry record.
3238 //
3239 // The classpath_index field is used to find the entry on the boot loader class
3240 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3241 // in an unnamed module. It is also used to indicate (for all packages whose
3242 // classes are loaded by the boot loader) that at least one of the package's
3243 // classes has been loaded.
3244 void InstanceKlass::set_classpath_index(s2 path_index) {
3245 if (_package_entry != nullptr) {
3246 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3247 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3248 assert(path_index != -1, "Unexpected classpath_index");
3249 _package_entry->set_classpath_index(path_index);
3250 }
3251 }
3252
3253 // different versions of is_same_class_package
3254
3255 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3256 oop classloader1 = this->class_loader();
3257 PackageEntry* classpkg1 = this->package();
3258 if (class2->is_objArray_klass()) {
3259 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3260 }
3261
3262 oop classloader2;
3263 PackageEntry* classpkg2;
3264 if (class2->is_instance_klass()) {
3265 classloader2 = class2->class_loader();
3266 classpkg2 = class2->package();
3267 } else {
3268 assert(class2->is_typeArray_klass(), "should be type array");
3269 classloader2 = nullptr;
3270 classpkg2 = nullptr;
3271 }
3272
3273 // Same package is determined by comparing class loader
3274 // and package entries. Both must be the same. This rule
3275 // applies even to classes that are defined in the unnamed
3276 // package, they still must have the same class loader.
3277 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3278 return true;
3279 }
3280
3281 return false;
3282 }
3283
3284 // return true if this class and other_class are in the same package. Classloader
3285 // and classname information is enough to determine a class's package
3286 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3287 const Symbol* other_class_name) const {
3288 if (class_loader() != other_class_loader) {
3289 return false;
3290 }
3291 if (name()->fast_compare(other_class_name) == 0) {
3292 return true;
3293 }
3294
3295 {
3296 ResourceMark rm;
3297
3298 bool bad_class_name = false;
3299 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3300 if (bad_class_name) {
3301 return false;
3302 }
3303 // Check that package_from_class_name() returns null, not "", if there is no package.
3304 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3305
3306 const Symbol* const this_package_name =
3307 this->package() != nullptr ? this->package()->name() : nullptr;
3308
3309 if (this_package_name == nullptr || other_pkg == nullptr) {
3310 // One of the two doesn't have a package. Only return true if the other
3311 // one also doesn't have a package.
3312 return this_package_name == other_pkg;
3313 }
3314
3315 // Check if package is identical
3316 return this_package_name->fast_compare(other_pkg) == 0;
3317 }
3318 }
3319
3320 static bool is_prohibited_package_slow(Symbol* class_name) {
3321 // Caller has ResourceMark
3322 int length;
3323 jchar* unicode = class_name->as_unicode(length);
3324 return (length >= 5 &&
3325 unicode[0] == 'j' &&
3326 unicode[1] == 'a' &&
3327 unicode[2] == 'v' &&
3328 unicode[3] == 'a' &&
3329 unicode[4] == '/');
3330 }
3331
3332 // Only boot and platform class loaders can define classes in "java/" packages.
3333 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3334 ClassLoaderData* loader_data,
3335 TRAPS) {
3336 if (!loader_data->is_boot_class_loader_data() &&
3337 !loader_data->is_platform_class_loader_data() &&
3338 class_name != nullptr && class_name->utf8_length() >= 5) {
3339 ResourceMark rm(THREAD);
3340 bool prohibited;
3341 const u1* base = class_name->base();
3342 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3343 prohibited = is_prohibited_package_slow(class_name);
3344 } else {
3345 char* name = class_name->as_C_string();
3346 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3347 }
3348 if (prohibited) {
3349 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3350 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3351 char* name = pkg_name->as_C_string();
3352 const char* class_loader_name = loader_data->loader_name_and_id();
3353 StringUtils::replace_no_expand(name, "/", ".");
3354 const char* msg_text1 = "Class loader (instance of): ";
3355 const char* msg_text2 = " tried to load prohibited package name: ";
3356 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3357 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3358 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3359 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3360 }
3361 }
3362 return;
3363 }
3364
3365 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3366 constantPoolHandle i_cp(THREAD, constants());
3367 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3368 int ioff = iter.inner_class_info_index();
3369 if (ioff != 0) {
3370 // Check to see if the name matches the class we're looking for
3371 // before attempting to find the class.
3372 if (i_cp->klass_name_at_matches(this, ioff)) {
3373 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3374 if (this == inner_klass) {
3375 *ooff = iter.outer_class_info_index();
3376 *noff = iter.inner_name_index();
3377 return true;
3378 }
3379 }
3380 }
3381 }
3382 return false;
3383 }
3384
3385 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3386 InstanceKlass* outer_klass = nullptr;
3387 *inner_is_member = false;
3388 int ooff = 0, noff = 0;
3389 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3390 if (has_inner_classes_attr) {
3391 constantPoolHandle i_cp(THREAD, constants());
3392 if (ooff != 0) {
3393 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3394 if (!ok->is_instance_klass()) {
3395 // If the outer class is not an instance klass then it cannot have
3396 // declared any inner classes.
3397 ResourceMark rm(THREAD);
3398 Exceptions::fthrow(
3399 THREAD_AND_LOCATION,
3400 vmSymbols::java_lang_IncompatibleClassChangeError(),
3401 "%s and %s disagree on InnerClasses attribute",
3402 ok->external_name(),
3403 external_name());
3404 return nullptr;
3405 }
3406 outer_klass = InstanceKlass::cast(ok);
3407 *inner_is_member = true;
3408 }
3409 if (nullptr == outer_klass) {
3410 // It may be a local class; try for that.
3411 int encl_method_class_idx = enclosing_method_class_index();
3412 if (encl_method_class_idx != 0) {
3413 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3414 outer_klass = InstanceKlass::cast(ok);
3415 *inner_is_member = false;
3416 }
3417 }
3418 }
3419
3420 // If no inner class attribute found for this class.
3421 if (nullptr == outer_klass) return nullptr;
3422
3423 // Throws an exception if outer klass has not declared k as an inner klass
3424 // We need evidence that each klass knows about the other, or else
3425 // the system could allow a spoof of an inner class to gain access rights.
3426 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3427 return outer_klass;
3428 }
3429
3430 jint InstanceKlass::compute_modifier_flags() const {
3431 jint access = access_flags().as_int();
3432
3433 // But check if it happens to be member class.
3434 InnerClassesIterator iter(this);
3435 for (; !iter.done(); iter.next()) {
3436 int ioff = iter.inner_class_info_index();
3437 // Inner class attribute can be zero, skip it.
3438 // Strange but true: JVM spec. allows null inner class refs.
3439 if (ioff == 0) continue;
3440
3441 // only look at classes that are already loaded
3442 // since we are looking for the flags for our self.
3443 Symbol* inner_name = constants()->klass_name_at(ioff);
3444 if (name() == inner_name) {
3445 // This is really a member class.
3446 access = iter.inner_access_flags();
3447 break;
3448 }
3449 }
3450 return (access & JVM_ACC_WRITTEN_FLAGS);
3451 }
3452
3453 jint InstanceKlass::jvmti_class_status() const {
3454 jint result = 0;
3455
3456 if (is_linked()) {
3457 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3458 }
3459
3460 if (is_initialized()) {
3461 assert(is_linked(), "Class status is not consistent");
3462 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3463 }
3464 if (is_in_error_state()) {
3465 result |= JVMTI_CLASS_STATUS_ERROR;
3466 }
3467 return result;
3468 }
3469
3470 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3471 bool implements_interface; // initialized by method_at_itable_or_null
3472 Method* m = method_at_itable_or_null(holder, index,
3473 implements_interface); // out parameter
3474 if (m != nullptr) {
3475 assert(implements_interface, "sanity");
3476 return m;
3477 } else if (implements_interface) {
3478 // Throw AbstractMethodError since corresponding itable slot is empty.
3479 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3480 } else {
3481 // If the interface isn't implemented by the receiver class,
3482 // the VM should throw IncompatibleClassChangeError.
3483 ResourceMark rm(THREAD);
3484 stringStream ss;
3485 bool same_module = (module() == holder->module());
3486 ss.print("Receiver class %s does not implement "
3487 "the interface %s defining the method to be called "
3488 "(%s%s%s)",
3489 external_name(), holder->external_name(),
3490 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3491 (same_module) ? "" : "; ",
3492 (same_module) ? "" : holder->class_in_module_of_loader());
3493 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3494 }
3495 }
3496
3497 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3498 klassItable itable(this);
3499 for (int i = 0; i < itable.size_offset_table(); i++) {
3500 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3501 if (offset_entry->interface_klass() == holder) {
3502 implements_interface = true;
3503 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3504 Method* m = ime[index].method();
3505 return m;
3506 }
3507 }
3508 implements_interface = false;
3509 return nullptr; // offset entry not found
3510 }
3511
3512 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3513 assert(is_linked(), "required");
3514 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3515 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3516
3517 int vtable_index = Method::invalid_vtable_index;
3518 Symbol* name = intf_method->name();
3519 Symbol* signature = intf_method->signature();
3520
3521 // First check in default method array
3522 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3523 int index = find_method_index(default_methods(),
3524 name, signature,
3525 Klass::OverpassLookupMode::find,
3526 Klass::StaticLookupMode::find,
3527 Klass::PrivateLookupMode::find);
3528 if (index >= 0) {
3529 vtable_index = default_vtable_indices()->at(index);
3530 }
3531 }
3532 if (vtable_index == Method::invalid_vtable_index) {
3533 // get vtable_index for miranda methods
3534 klassVtable vt = vtable();
3535 vtable_index = vt.index_of_miranda(name, signature);
3536 }
3537 return vtable_index;
3538 }
3539
3540 #if INCLUDE_JVMTI
3541 // update default_methods for redefineclasses for methods that are
3542 // not yet in the vtable due to concurrent subclass define and superinterface
3543 // redefinition
3544 // Note: those in the vtable, should have been updated via adjust_method_entries
3545 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3546 // search the default_methods for uses of either obsolete or EMCP methods
3547 if (default_methods() != nullptr) {
3548 for (int index = 0; index < default_methods()->length(); index ++) {
3549 Method* old_method = default_methods()->at(index);
3550 if (old_method == nullptr || !old_method->is_old()) {
3551 continue; // skip uninteresting entries
3552 }
3553 assert(!old_method->is_deleted(), "default methods may not be deleted");
3554 Method* new_method = old_method->get_new_method();
3555 default_methods()->at_put(index, new_method);
3556
3557 if (log_is_enabled(Info, redefine, class, update)) {
3558 ResourceMark rm;
3559 if (!(*trace_name_printed)) {
3560 log_info(redefine, class, update)
3561 ("adjust: klassname=%s default methods from name=%s",
3562 external_name(), old_method->method_holder()->external_name());
3563 *trace_name_printed = true;
3564 }
3565 log_debug(redefine, class, update, vtables)
3566 ("default method update: %s(%s) ",
3567 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3568 }
3569 }
3570 }
3571 }
3572 #endif // INCLUDE_JVMTI
3573
3574 // On-stack replacement stuff
3575 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3576 assert_lock_strong(NMethodState_lock);
3577 #ifndef PRODUCT
3578 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3579 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3580 "redundant OSR recompilation detected. memory leak in CodeCache!");
3581 #endif
3582 // only one compilation can be active
3583 assert(n->is_osr_method(), "wrong kind of nmethod");
3584 n->set_osr_link(osr_nmethods_head());
3585 set_osr_nmethods_head(n);
3586 // Raise the highest osr level if necessary
3587 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3588
3589 // Get rid of the osr methods for the same bci that have lower levels.
3590 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3591 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3592 if (inv != nullptr && inv->is_in_use()) {
3593 inv->make_not_entrant();
3594 }
3595 }
3596 }
3597
3598 // Remove osr nmethod from the list. Return true if found and removed.
3599 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3600 // This is a short non-blocking critical region, so the no safepoint check is ok.
3601 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3602 assert(n->is_osr_method(), "wrong kind of nmethod");
3603 nmethod* last = nullptr;
3604 nmethod* cur = osr_nmethods_head();
3605 int max_level = CompLevel_none; // Find the max comp level excluding n
3606 Method* m = n->method();
3607 // Search for match
3608 bool found = false;
3609 while(cur != nullptr && cur != n) {
3610 if (m == cur->method()) {
3611 // Find max level before n
3612 max_level = MAX2(max_level, cur->comp_level());
3613 }
3614 last = cur;
3615 cur = cur->osr_link();
3616 }
3617 nmethod* next = nullptr;
3618 if (cur == n) {
3619 found = true;
3620 next = cur->osr_link();
3621 if (last == nullptr) {
3622 // Remove first element
3623 set_osr_nmethods_head(next);
3624 } else {
3625 last->set_osr_link(next);
3626 }
3627 }
3628 n->set_osr_link(nullptr);
3629 cur = next;
3630 while (cur != nullptr) {
3631 // Find max level after n
3632 if (m == cur->method()) {
3633 max_level = MAX2(max_level, cur->comp_level());
3634 }
3635 cur = cur->osr_link();
3636 }
3637 m->set_highest_osr_comp_level(max_level);
3638 return found;
3639 }
3640
3641 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3642 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3643 nmethod* osr = osr_nmethods_head();
3644 int found = 0;
3645 while (osr != nullptr) {
3646 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3647 if (osr->method() == m) {
3648 deopt_scope->mark(osr);
3649 found++;
3650 }
3651 osr = osr->osr_link();
3652 }
3653 return found;
3654 }
3655
3656 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3657 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3658 nmethod* osr = osr_nmethods_head();
3659 nmethod* best = nullptr;
3660 while (osr != nullptr) {
3661 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3662 // There can be a time when a c1 osr method exists but we are waiting
3663 // for a c2 version. When c2 completes its osr nmethod we will trash
3664 // the c1 version and only be able to find the c2 version. However
3665 // while we overflow in the c1 code at back branches we don't want to
3666 // try and switch to the same code as we are already running
3667
3668 if (osr->method() == m &&
3669 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3670 if (match_level) {
3671 if (osr->comp_level() == comp_level) {
3672 // Found a match - return it.
3673 return osr;
3674 }
3675 } else {
3676 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3677 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3678 // Found the best possible - return it.
3679 return osr;
3680 }
3681 best = osr;
3682 }
3683 }
3684 }
3685 osr = osr->osr_link();
3686 }
3687
3688 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3689 if (best != nullptr && best->comp_level() >= comp_level) {
3690 return best;
3691 }
3692 return nullptr;
3693 }
3694
3695 // -----------------------------------------------------------------------------------------------------
3696 // Printing
3697
3698 #define BULLET " - "
3699
3700 static const char* state_names[] = {
3701 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3702 };
3703
3704 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3705 ResourceMark rm;
3706 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3707 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3708 for (int i = 0; i < len; i++) {
3709 intptr_t e = start[i];
3710 st->print("%d : " INTPTR_FORMAT, i, e);
3711 if (forward_refs[i] != 0) {
3712 int from = forward_refs[i];
3713 int off = (int) start[from];
3714 st->print(" (offset %d <= [%d])", off, from);
3715 }
3716 if (MetaspaceObj::is_valid((Metadata*)e)) {
3717 st->print(" ");
3718 ((Metadata*)e)->print_value_on(st);
3719 } else if (self != nullptr && e > 0 && e < 0x10000) {
3720 address location = self + e;
3721 int index = (int)((intptr_t*)location - start);
3722 st->print(" (offset %d => [%d])", (int)e, index);
3723 if (index >= 0 && index < len)
3724 forward_refs[index] = i;
3725 }
3726 st->cr();
3727 }
3728 }
3729
3730 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3731 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3732 }
3733
3734 template<typename T>
3735 static void print_array_on(outputStream* st, Array<T>* array) {
3736 if (array == nullptr) { st->print_cr("nullptr"); return; }
3737 array->print_value_on(st); st->cr();
3738 if (Verbose || WizardMode) {
3739 for (int i = 0; i < array->length(); i++) {
3740 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3741 }
3742 }
3743 }
3744
3745 static void print_array_on(outputStream* st, Array<int>* array) {
3746 if (array == nullptr) { st->print_cr("nullptr"); return; }
3747 array->print_value_on(st); st->cr();
3748 if (Verbose || WizardMode) {
3749 for (int i = 0; i < array->length(); i++) {
3750 st->print("%d : %d", i, array->at(i)); st->cr();
3751 }
3752 }
3753 }
3754
3755 const char* InstanceKlass::init_state_name() const {
3756 return state_names[init_state()];
3757 }
3758
3759 void InstanceKlass::print_on(outputStream* st) const {
3760 assert(is_klass(), "must be klass");
3761 Klass::print_on(st);
3762
3763 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3764 st->print(BULLET"klass size: %d", size()); st->cr();
3765 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3766 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3767 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3768 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3769 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3770 st->print(BULLET"sub: ");
3771 Klass* sub = subklass();
3772 int n;
3773 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3774 if (n < MaxSubklassPrintSize) {
3775 sub->print_value_on(st);
3776 st->print(" ");
3777 }
3778 }
3779 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3780 st->cr();
3781
3782 if (is_interface()) {
3783 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3784 if (nof_implementors() == 1) {
3785 st->print_cr(BULLET"implementor: ");
3786 st->print(" ");
3787 implementor()->print_value_on(st);
3788 st->cr();
3789 }
3790 }
3791
3792 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3793 st->print(BULLET"methods: "); print_array_on(st, methods());
3794 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3795 if (default_methods() != nullptr) {
3796 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3797 }
3798 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3799 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3800 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3801
3802 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3803
3804 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3805 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr();
3806
3807 if (secondary_supers() != nullptr) {
3808 if (Verbose) {
3809 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3810 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3811 for (int i = 0; i < _secondary_supers->length(); i++) {
3812 ResourceMark rm; // for external_name()
3813 Klass* secondary_super = _secondary_supers->at(i);
3814 st->print(BULLET"%2d:", i);
3815 if (is_hashed) {
3816 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap);
3817 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3818 st->print(" dist:%02d:", distance);
3819 }
3820 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3821 }
3822 }
3823 }
3824 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3825
3826 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3827 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3828 if (source_debug_extension() != nullptr) {
3829 st->print(BULLET"source debug extension: ");
3830 st->print("%s", source_debug_extension());
3831 st->cr();
3832 }
3833 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3834 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3835 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3836 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3837 {
3838 bool have_pv = false;
3839 // previous versions are linked together through the InstanceKlass
3840 for (InstanceKlass* pv_node = previous_versions();
3841 pv_node != nullptr;
3842 pv_node = pv_node->previous_versions()) {
3843 if (!have_pv)
3844 st->print(BULLET"previous version: ");
3845 have_pv = true;
3846 pv_node->constants()->print_value_on(st);
3847 }
3848 if (have_pv) st->cr();
3849 }
3850
3851 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3852 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3853 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3854 print_on_maybe_null(st, BULLET"record components: ", record_components());
3855 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3856 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
3857 if (java_mirror() != nullptr) {
3858 st->print(BULLET"java mirror: ");
3859 java_mirror()->print_value_on(st);
3860 st->cr();
3861 } else {
3862 st->print_cr(BULLET"java mirror: null");
3863 }
3864 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3865 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3866 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3867 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3868 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3869
3870 FieldPrinter print_static_field(st);
3871 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3872 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3873 FieldPrinter print_nonstatic_field(st);
3874 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3875 ik->print_nonstatic_fields(&print_nonstatic_field);
3876
3877 st->print(BULLET"non-static oop maps: ");
3878 OopMapBlock* map = start_of_nonstatic_oop_maps();
3879 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3880 while (map < end_map) {
3881 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3882 map++;
3883 }
3884 st->cr();
3885 }
3886
3887 void InstanceKlass::print_value_on(outputStream* st) const {
3888 assert(is_klass(), "must be klass");
3889 if (Verbose || WizardMode) access_flags().print_on(st);
3890 name()->print_value_on(st);
3891 }
3892
3893 void FieldPrinter::do_field(fieldDescriptor* fd) {
3894 _st->print(BULLET);
3895 if (_obj == nullptr) {
3896 fd->print_on(_st);
3897 _st->cr();
3898 } else {
3899 fd->print_on_for(_st, _obj);
3900 _st->cr();
3901 }
3902 }
3903
3904
3905 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3906 Klass::oop_print_on(obj, st);
3907
3908 if (this == vmClasses::String_klass()) {
3909 typeArrayOop value = java_lang_String::value(obj);
3910 juint length = java_lang_String::length(obj);
3911 if (value != nullptr &&
3912 value->is_typeArray() &&
3913 length <= (juint) value->length()) {
3914 st->print(BULLET"string: ");
3915 java_lang_String::print(obj, st);
3916 st->cr();
3917 }
3918 }
3919
3920 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3921 FieldPrinter print_field(st, obj);
3922 print_nonstatic_fields(&print_field);
3923
3924 if (this == vmClasses::Class_klass()) {
3925 st->print(BULLET"signature: ");
3926 java_lang_Class::print_signature(obj, st);
3927 st->cr();
3928 Klass* real_klass = java_lang_Class::as_Klass(obj);
3929 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3930 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3931 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3932 }
3933 } else if (this == vmClasses::MethodType_klass()) {
3934 st->print(BULLET"signature: ");
3935 java_lang_invoke_MethodType::print_signature(obj, st);
3936 st->cr();
3937 }
3938 }
3939
3940 #ifndef PRODUCT
3941
3942 bool InstanceKlass::verify_itable_index(int i) {
3943 int method_count = klassItable::method_count_for_interface(this);
3944 assert(i >= 0 && i < method_count, "index out of bounds");
3945 return true;
3946 }
3947
3948 #endif //PRODUCT
3949
3950 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3951 st->print("a ");
3952 name()->print_value_on(st);
3953 obj->print_address_on(st);
3954 if (this == vmClasses::String_klass()
3955 && java_lang_String::value(obj) != nullptr) {
3956 ResourceMark rm;
3957 int len = java_lang_String::length(obj);
3958 int plen = (len < 24 ? len : 12);
3959 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3960 st->print(" = \"%s\"", str);
3961 if (len > plen)
3962 st->print("...[%d]", len);
3963 } else if (this == vmClasses::Class_klass()) {
3964 Klass* k = java_lang_Class::as_Klass(obj);
3965 st->print(" = ");
3966 if (k != nullptr) {
3967 k->print_value_on(st);
3968 } else {
3969 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3970 st->print("%s", tname ? tname : "type?");
3971 }
3972 } else if (this == vmClasses::MethodType_klass()) {
3973 st->print(" = ");
3974 java_lang_invoke_MethodType::print_signature(obj, st);
3975 } else if (java_lang_boxing_object::is_instance(obj)) {
3976 st->print(" = ");
3977 java_lang_boxing_object::print(obj, st);
3978 } else if (this == vmClasses::LambdaForm_klass()) {
3979 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3980 if (vmentry != nullptr) {
3981 st->print(" => ");
3982 vmentry->print_value_on(st);
3983 }
3984 } else if (this == vmClasses::MemberName_klass()) {
3985 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3986 if (vmtarget != nullptr) {
3987 st->print(" = ");
3988 vmtarget->print_value_on(st);
3989 } else {
3990 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3991 oop name = java_lang_invoke_MemberName::name(obj);
3992 if (clazz != nullptr) {
3993 clazz->print_value_on(st);
3994 } else {
3995 st->print("null");
3996 }
3997 st->print(".");
3998 if (name != nullptr) {
3999 name->print_value_on(st);
4000 } else {
4001 st->print("null");
4002 }
4003 }
4004 }
4005 }
4006
4007 const char* InstanceKlass::internal_name() const {
4008 return external_name();
4009 }
4010
4011 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4012 const ModuleEntry* module_entry,
4013 const ClassFileStream* cfs) const {
4014
4015 if (ClassListWriter::is_enabled()) {
4016 ClassListWriter::write(this, cfs);
4017 }
4018
4019 print_class_load_helper(loader_data, module_entry, cfs);
4020 print_class_load_cause_logging();
4021 }
4022
4023 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4024 const ModuleEntry* module_entry,
4025 const ClassFileStream* cfs) const {
4026
4027 if (!log_is_enabled(Info, class, load)) {
4028 return;
4029 }
4030
4031 ResourceMark rm;
4032 LogMessage(class, load) msg;
4033 stringStream info_stream;
4034
4035 // Name and class hierarchy info
4036 info_stream.print("%s", external_name());
4037
4038 // Source
4039 if (cfs != nullptr) {
4040 if (cfs->source() != nullptr) {
4041 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4042 if (module_name != nullptr) {
4043 // When the boot loader created the stream, it didn't know the module name
4044 // yet. Let's format it now.
4045 if (cfs->from_boot_loader_modules_image()) {
4046 info_stream.print(" source: jrt:/%s", module_name);
4047 } else {
4048 info_stream.print(" source: %s", cfs->source());
4049 }
4050 } else {
4051 info_stream.print(" source: %s", cfs->source());
4052 }
4053 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4054 Thread* current = Thread::current();
4055 Klass* caller = current->is_Java_thread() ?
4056 JavaThread::cast(current)->security_get_caller_class(1):
4057 nullptr;
4058 // caller can be null, for example, during a JVMTI VM_Init hook
4059 if (caller != nullptr) {
4060 info_stream.print(" source: instance of %s", caller->external_name());
4061 } else {
4062 // source is unknown
4063 }
4064 } else {
4065 oop class_loader = loader_data->class_loader();
4066 info_stream.print(" source: %s", class_loader->klass()->external_name());
4067 }
4068 } else {
4069 assert(this->is_shared(), "must be");
4070 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4071 info_stream.print(" source: shared objects file (top)");
4072 } else {
4073 info_stream.print(" source: shared objects file");
4074 }
4075 }
4076
4077 msg.info("%s", info_stream.as_string());
4078
4079 if (log_is_enabled(Debug, class, load)) {
4080 stringStream debug_stream;
4081
4082 // Class hierarchy info
4083 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4084 p2i(this), p2i(superklass()));
4085
4086 // Interfaces
4087 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4088 debug_stream.print(" interfaces:");
4089 int length = local_interfaces()->length();
4090 for (int i = 0; i < length; i++) {
4091 debug_stream.print(" " PTR_FORMAT,
4092 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4093 }
4094 }
4095
4096 // Class loader
4097 debug_stream.print(" loader: [");
4098 loader_data->print_value_on(&debug_stream);
4099 debug_stream.print("]");
4100
4101 // Classfile checksum
4102 if (cfs) {
4103 debug_stream.print(" bytes: %d checksum: %08x",
4104 cfs->length(),
4105 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4106 cfs->length()));
4107 }
4108
4109 msg.debug("%s", debug_stream.as_string());
4110 }
4111 }
4112
4113 void InstanceKlass::print_class_load_cause_logging() const {
4114 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4115 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4116 JavaThread* current = JavaThread::current();
4117 ResourceMark rm(current);
4118 const char* name = external_name();
4119
4120 if (LogClassLoadingCauseFor == nullptr ||
4121 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4122 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4123 return;
4124 }
4125
4126 // Log Java stack first
4127 {
4128 LogMessage(class, load, cause) msg;
4129 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4130
4131 info_stream.print_cr("Java stack when loading %s:", name);
4132 current->print_stack_on(&info_stream);
4133 }
4134
4135 // Log native stack second
4136 if (log_cause_native) {
4137 // Log to string first so that lines can be indented
4138 stringStream stack_stream;
4139 char buf[O_BUFLEN];
4140 address lastpc = nullptr;
4141 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4142 // We have printed the native stack in platform-specific code,
4143 // so nothing else to do in this case.
4144 } else {
4145 frame f = os::current_frame();
4146 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4147 -1 /* max stack_stream */, buf, O_BUFLEN);
4148 }
4149
4150 LogMessage(class, load, cause, native) msg;
4151 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4152 info_stream.print_cr("Native stack when loading %s:", name);
4153
4154 // Print each native stack line to the log
4155 int size = (int) stack_stream.size();
4156 char* stack = stack_stream.as_string();
4157 char* stack_end = stack + size;
4158 char* line_start = stack;
4159 for (char* p = stack; p < stack_end; p++) {
4160 if (*p == '\n') {
4161 *p = '\0';
4162 info_stream.print_cr("\t%s", line_start);
4163 line_start = p + 1;
4164 }
4165 }
4166 if (line_start < stack_end) {
4167 info_stream.print_cr("\t%s", line_start);
4168 }
4169 }
4170 }
4171 }
4172
4173 // Verification
4174
4175 class VerifyFieldClosure: public BasicOopIterateClosure {
4176 protected:
4177 template <class T> void do_oop_work(T* p) {
4178 oop obj = RawAccess<>::oop_load(p);
4179 if (!oopDesc::is_oop_or_null(obj)) {
4180 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4181 Universe::print_on(tty);
4182 guarantee(false, "boom");
4183 }
4184 }
4185 public:
4186 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4187 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4188 };
4189
4190 void InstanceKlass::verify_on(outputStream* st) {
4191 #ifndef PRODUCT
4192 // Avoid redundant verifies, this really should be in product.
4193 if (_verify_count == Universe::verify_count()) return;
4194 _verify_count = Universe::verify_count();
4195 #endif
4196
4197 // Verify Klass
4198 Klass::verify_on(st);
4199
4200 // Verify that klass is present in ClassLoaderData
4201 guarantee(class_loader_data()->contains_klass(this),
4202 "this class isn't found in class loader data");
4203
4204 // Verify vtables
4205 if (is_linked()) {
4206 // $$$ This used to be done only for m/s collections. Doing it
4207 // always seemed a valid generalization. (DLD -- 6/00)
4208 vtable().verify(st);
4209 }
4210
4211 // Verify first subklass
4212 if (subklass() != nullptr) {
4213 guarantee(subklass()->is_klass(), "should be klass");
4214 }
4215
4216 // Verify siblings
4217 Klass* super = this->super();
4218 Klass* sib = next_sibling();
4219 if (sib != nullptr) {
4220 if (sib == this) {
4221 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4222 }
4223
4224 guarantee(sib->is_klass(), "should be klass");
4225 guarantee(sib->super() == super, "siblings should have same superklass");
4226 }
4227
4228 // Verify local interfaces
4229 if (local_interfaces()) {
4230 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4231 for (int j = 0; j < local_interfaces->length(); j++) {
4232 InstanceKlass* e = local_interfaces->at(j);
4233 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4234 }
4235 }
4236
4237 // Verify transitive interfaces
4238 if (transitive_interfaces() != nullptr) {
4239 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4240 for (int j = 0; j < transitive_interfaces->length(); j++) {
4241 InstanceKlass* e = transitive_interfaces->at(j);
4242 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4243 }
4244 }
4245
4246 // Verify methods
4247 if (methods() != nullptr) {
4248 Array<Method*>* methods = this->methods();
4249 for (int j = 0; j < methods->length(); j++) {
4250 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4251 }
4252 for (int j = 0; j < methods->length() - 1; j++) {
4253 Method* m1 = methods->at(j);
4254 Method* m2 = methods->at(j + 1);
4255 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4256 }
4257 }
4258
4259 // Verify method ordering
4260 if (method_ordering() != nullptr) {
4261 Array<int>* method_ordering = this->method_ordering();
4262 int length = method_ordering->length();
4263 if (JvmtiExport::can_maintain_original_method_order() ||
4264 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4265 guarantee(length == methods()->length(), "invalid method ordering length");
4266 jlong sum = 0;
4267 for (int j = 0; j < length; j++) {
4268 int original_index = method_ordering->at(j);
4269 guarantee(original_index >= 0, "invalid method ordering index");
4270 guarantee(original_index < length, "invalid method ordering index");
4271 sum += original_index;
4272 }
4273 // Verify sum of indices 0,1,...,length-1
4274 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4275 } else {
4276 guarantee(length == 0, "invalid method ordering length");
4277 }
4278 }
4279
4280 // Verify default methods
4281 if (default_methods() != nullptr) {
4282 Array<Method*>* methods = this->default_methods();
4283 for (int j = 0; j < methods->length(); j++) {
4284 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4285 }
4286 for (int j = 0; j < methods->length() - 1; j++) {
4287 Method* m1 = methods->at(j);
4288 Method* m2 = methods->at(j + 1);
4289 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4290 }
4291 }
4292
4293 // Verify JNI static field identifiers
4294 if (jni_ids() != nullptr) {
4295 jni_ids()->verify(this);
4296 }
4297
4298 // Verify other fields
4299 if (constants() != nullptr) {
4300 guarantee(constants()->is_constantPool(), "should be constant pool");
4301 }
4302 }
4303
4304 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4305 Klass::oop_verify_on(obj, st);
4306 VerifyFieldClosure blk;
4307 obj->oop_iterate(&blk);
4308 }
4309
4310
4311 // JNIid class for jfieldIDs only
4312 // Note to reviewers:
4313 // These JNI functions are just moved over to column 1 and not changed
4314 // in the compressed oops workspace.
4315 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4316 _holder = holder;
4317 _offset = offset;
4318 _next = next;
4319 debug_only(_is_static_field_id = false;)
4320 }
4321
4322
4323 JNIid* JNIid::find(int offset) {
4324 JNIid* current = this;
4325 while (current != nullptr) {
4326 if (current->offset() == offset) return current;
4327 current = current->next();
4328 }
4329 return nullptr;
4330 }
4331
4332 void JNIid::deallocate(JNIid* current) {
4333 while (current != nullptr) {
4334 JNIid* next = current->next();
4335 delete current;
4336 current = next;
4337 }
4338 }
4339
4340
4341 void JNIid::verify(Klass* holder) {
4342 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4343 int end_field_offset;
4344 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4345
4346 JNIid* current = this;
4347 while (current != nullptr) {
4348 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4349 #ifdef ASSERT
4350 int o = current->offset();
4351 if (current->is_static_field_id()) {
4352 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4353 }
4354 #endif
4355 current = current->next();
4356 }
4357 }
4358
4359 void InstanceKlass::set_init_state(ClassState state) {
4360 #ifdef ASSERT
4361 bool good_state = is_shared() ? (_init_state <= state)
4362 : (_init_state < state);
4363 assert(good_state || state == allocated, "illegal state transition");
4364 #endif
4365 assert(_init_thread == nullptr, "should be cleared before state change");
4366 Atomic::release_store(&_init_state, state);
4367 }
4368
4369 #if INCLUDE_JVMTI
4370
4371 // RedefineClasses() support for previous versions
4372
4373 // Globally, there is at least one previous version of a class to walk
4374 // during class unloading, which is saved because old methods in the class
4375 // are still running. Otherwise the previous version list is cleaned up.
4376 bool InstanceKlass::_should_clean_previous_versions = false;
4377
4378 // Returns true if there are previous versions of a class for class
4379 // unloading only. Also resets the flag to false. purge_previous_version
4380 // will set the flag to true if there are any left, i.e., if there's any
4381 // work to do for next time. This is to avoid the expensive code cache
4382 // walk in CLDG::clean_deallocate_lists().
4383 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4384 bool ret = _should_clean_previous_versions;
4385 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4386 ret ? "true" : "false");
4387 _should_clean_previous_versions = false;
4388 return ret;
4389 }
4390
4391 // This nulls out jmethodIDs for all methods in 'klass'
4392 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4393 // during class unloading.
4394 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4395 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4396 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4397 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4398 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4399 Array<Method*>* method_refs = klass->methods();
4400 for (int k = 0; k < method_refs->length(); k++) {
4401 Method* method = method_refs->at(k);
4402 if (method != nullptr && method->is_obsolete()) {
4403 method->clear_jmethod_id();
4404 }
4405 }
4406 }
4407
4408 // Purge previous versions before adding new previous versions of the class and
4409 // during class unloading.
4410 void InstanceKlass::purge_previous_version_list() {
4411 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4412 assert(has_been_redefined(), "Should only be called for main class");
4413
4414 // Quick exit.
4415 if (previous_versions() == nullptr) {
4416 return;
4417 }
4418
4419 // This klass has previous versions so see what we can cleanup
4420 // while it is safe to do so.
4421
4422 int deleted_count = 0; // leave debugging breadcrumbs
4423 int live_count = 0;
4424 ClassLoaderData* loader_data = class_loader_data();
4425 assert(loader_data != nullptr, "should never be null");
4426
4427 ResourceMark rm;
4428 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4429
4430 // previous versions are linked together through the InstanceKlass
4431 InstanceKlass* pv_node = previous_versions();
4432 InstanceKlass* last = this;
4433 int version = 0;
4434
4435 // check the previous versions list
4436 for (; pv_node != nullptr; ) {
4437
4438 ConstantPool* pvcp = pv_node->constants();
4439 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4440
4441 if (!pvcp->on_stack()) {
4442 // If the constant pool isn't on stack, none of the methods
4443 // are executing. Unlink this previous_version.
4444 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4445 // so will be deallocated during the next phase of class unloading.
4446 log_trace(redefine, class, iklass, purge)
4447 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4448 // Unlink from previous version list.
4449 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4450 InstanceKlass* next = pv_node->previous_versions();
4451 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4452 pv_node->link_previous_versions(nullptr); // point next to null
4453 last->link_previous_versions(next);
4454 // Delete this node directly. Nothing is referring to it and we don't
4455 // want it to increase the counter for metadata to delete in CLDG.
4456 MetadataFactory::free_metadata(loader_data, pv_node);
4457 pv_node = next;
4458 deleted_count++;
4459 version++;
4460 continue;
4461 } else {
4462 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4463 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4464 live_count++;
4465 if (pvcp->is_shared()) {
4466 // Shared previous versions can never be removed so no cleaning is needed.
4467 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4468 } else {
4469 // Previous version alive, set that clean is needed for next time.
4470 _should_clean_previous_versions = true;
4471 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4472 }
4473 }
4474
4475 // next previous version
4476 last = pv_node;
4477 pv_node = pv_node->previous_versions();
4478 version++;
4479 }
4480 log_trace(redefine, class, iklass, purge)
4481 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4482 }
4483
4484 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4485 int emcp_method_count) {
4486 int obsolete_method_count = old_methods->length() - emcp_method_count;
4487
4488 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4489 _previous_versions != nullptr) {
4490 // We have a mix of obsolete and EMCP methods so we have to
4491 // clear out any matching EMCP method entries the hard way.
4492 int local_count = 0;
4493 for (int i = 0; i < old_methods->length(); i++) {
4494 Method* old_method = old_methods->at(i);
4495 if (old_method->is_obsolete()) {
4496 // only obsolete methods are interesting
4497 Symbol* m_name = old_method->name();
4498 Symbol* m_signature = old_method->signature();
4499
4500 // previous versions are linked together through the InstanceKlass
4501 int j = 0;
4502 for (InstanceKlass* prev_version = _previous_versions;
4503 prev_version != nullptr;
4504 prev_version = prev_version->previous_versions(), j++) {
4505
4506 Array<Method*>* method_refs = prev_version->methods();
4507 for (int k = 0; k < method_refs->length(); k++) {
4508 Method* method = method_refs->at(k);
4509
4510 if (!method->is_obsolete() &&
4511 method->name() == m_name &&
4512 method->signature() == m_signature) {
4513 // The current RedefineClasses() call has made all EMCP
4514 // versions of this method obsolete so mark it as obsolete
4515 log_trace(redefine, class, iklass, add)
4516 ("%s(%s): flush obsolete method @%d in version @%d",
4517 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4518
4519 method->set_is_obsolete();
4520 break;
4521 }
4522 }
4523
4524 // The previous loop may not find a matching EMCP method, but
4525 // that doesn't mean that we can optimize and not go any
4526 // further back in the PreviousVersion generations. The EMCP
4527 // method for this generation could have already been made obsolete,
4528 // but there still may be an older EMCP method that has not
4529 // been made obsolete.
4530 }
4531
4532 if (++local_count >= obsolete_method_count) {
4533 // no more obsolete methods so bail out now
4534 break;
4535 }
4536 }
4537 }
4538 }
4539 }
4540
4541 // Save the scratch_class as the previous version if any of the methods are running.
4542 // The previous_versions are used to set breakpoints in EMCP methods and they are
4543 // also used to clean MethodData links to redefined methods that are no longer running.
4544 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4545 int emcp_method_count) {
4546 assert(Thread::current()->is_VM_thread(),
4547 "only VMThread can add previous versions");
4548
4549 ResourceMark rm;
4550 log_trace(redefine, class, iklass, add)
4551 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4552
4553 // Clean out old previous versions for this class
4554 purge_previous_version_list();
4555
4556 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4557 // a previous redefinition may be made obsolete by this redefinition.
4558 Array<Method*>* old_methods = scratch_class->methods();
4559 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4560
4561 // If the constant pool for this previous version of the class
4562 // is not marked as being on the stack, then none of the methods
4563 // in this previous version of the class are on the stack so
4564 // we don't need to add this as a previous version.
4565 ConstantPool* cp_ref = scratch_class->constants();
4566 if (!cp_ref->on_stack()) {
4567 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4568 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4569 return;
4570 }
4571
4572 // Add previous version if any methods are still running or if this is
4573 // a shared class which should never be removed.
4574 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4575 scratch_class->link_previous_versions(previous_versions());
4576 link_previous_versions(scratch_class);
4577 if (cp_ref->is_shared()) {
4578 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4579 } else {
4580 // We only set clean_previous_versions flag for processing during class
4581 // unloading for non-shared classes.
4582 _should_clean_previous_versions = true;
4583 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4584 }
4585 } // end add_previous_version()
4586
4587 #endif // INCLUDE_JVMTI
4588
4589 Method* InstanceKlass::method_with_idnum(int idnum) {
4590 Method* m = nullptr;
4591 if (idnum < methods()->length()) {
4592 m = methods()->at(idnum);
4593 }
4594 if (m == nullptr || m->method_idnum() != idnum) {
4595 for (int index = 0; index < methods()->length(); ++index) {
4596 m = methods()->at(index);
4597 if (m->method_idnum() == idnum) {
4598 return m;
4599 }
4600 }
4601 // None found, return null for the caller to handle.
4602 return nullptr;
4603 }
4604 return m;
4605 }
4606
4607
4608 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4609 if (idnum >= methods()->length()) {
4610 return nullptr;
4611 }
4612 Method* m = methods()->at(idnum);
4613 if (m != nullptr && m->orig_method_idnum() == idnum) {
4614 return m;
4615 }
4616 // Obsolete method idnum does not match the original idnum
4617 for (int index = 0; index < methods()->length(); ++index) {
4618 m = methods()->at(index);
4619 if (m->orig_method_idnum() == idnum) {
4620 return m;
4621 }
4622 }
4623 // None found, return null for the caller to handle.
4624 return nullptr;
4625 }
4626
4627
4628 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4629 InstanceKlass* holder = get_klass_version(version);
4630 if (holder == nullptr) {
4631 return nullptr; // The version of klass is gone, no method is found
4632 }
4633 Method* method = holder->method_with_orig_idnum(idnum);
4634 return method;
4635 }
4636
4637 #if INCLUDE_JVMTI
4638 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4639 return _cached_class_file;
4640 }
4641
4642 jint InstanceKlass::get_cached_class_file_len() {
4643 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4644 }
4645
4646 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4647 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4648 }
4649 #endif
4650
4651 // Make a step iterating over the class hierarchy under the root class.
4652 // Skips subclasses if requested.
4653 void ClassHierarchyIterator::next() {
4654 assert(_current != nullptr, "required");
4655 if (_visit_subclasses && _current->subklass() != nullptr) {
4656 _current = _current->subklass();
4657 return; // visit next subclass
4658 }
4659 _visit_subclasses = true; // reset
4660 while (_current->next_sibling() == nullptr && _current != _root) {
4661 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4662 }
4663 if (_current == _root) {
4664 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4665 _current = nullptr;
4666 return;
4667 }
4668 _current = _current->next_sibling();
4669 return; // visit next sibling subclass
4670 }