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 "logging/logMessage.hpp"
55 #include "logging/logStream.hpp"
56 #include "memory/allocation.inline.hpp"
57 #include "memory/iterator.inline.hpp"
58 #include "memory/metadataFactory.hpp"
59 #include "memory/metaspaceClosure.hpp"
60 #include "memory/oopFactory.hpp"
61 #include "memory/resourceArea.hpp"
62 #include "memory/universe.hpp"
63 #include "oops/fieldStreams.inline.hpp"
64 #include "oops/constantPool.hpp"
65 #include "oops/instanceClassLoaderKlass.hpp"
66 #include "oops/instanceKlass.inline.hpp"
67 #include "oops/instanceMirrorKlass.hpp"
68 #include "oops/instanceOop.hpp"
69 #include "oops/instanceStackChunkKlass.hpp"
70 #include "oops/klass.inline.hpp"
71 #include "oops/method.hpp"
72 #include "oops/oop.inline.hpp"
73 #include "oops/recordComponent.hpp"
74 #include "oops/symbol.hpp"
75 #include "oops/inlineKlass.hpp"
76 #include "prims/jvmtiExport.hpp"
77 #include "prims/jvmtiRedefineClasses.hpp"
78 #include "prims/jvmtiThreadState.hpp"
79 #include "prims/methodComparator.hpp"
80 #include "runtime/arguments.hpp"
81 #include "runtime/deoptimization.hpp"
82 #include "runtime/atomic.hpp"
83 #include "runtime/fieldDescriptor.inline.hpp"
84 #include "runtime/handles.inline.hpp"
85 #include "runtime/javaCalls.hpp"
86 #include "runtime/javaThread.inline.hpp"
87 #include "runtime/mutexLocker.hpp"
88 #include "runtime/orderAccess.hpp"
89 #include "runtime/os.inline.hpp"
90 #include "runtime/reflection.hpp"
91 #include "runtime/synchronizer.hpp"
92 #include "runtime/threads.hpp"
93 #include "services/classLoadingService.hpp"
94 #include "services/finalizerService.hpp"
95 #include "services/threadService.hpp"
96 #include "utilities/dtrace.hpp"
97 #include "utilities/events.hpp"
98 #include "utilities/macros.hpp"
99 #include "utilities/stringUtils.hpp"
100 #include "utilities/pair.hpp"
101 #ifdef COMPILER1
102 #include "c1/c1_Compiler.hpp"
103 #endif
104 #if INCLUDE_JFR
105 #include "jfr/jfrEvents.hpp"
106 #endif
107
108 #ifdef DTRACE_ENABLED
109
110
111 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
112 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
113 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
114 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
115 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
116 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
117 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
118 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
119 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
120 { \
121 char* data = nullptr; \
122 int len = 0; \
123 Symbol* clss_name = name(); \
124 if (clss_name != nullptr) { \
125 data = (char*)clss_name->bytes(); \
126 len = clss_name->utf8_length(); \
127 } \
128 HOTSPOT_CLASS_INITIALIZATION_##type( \
129 data, len, (void*)class_loader(), thread_type); \
130 }
131
132 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
133 { \
134 char* data = nullptr; \
135 int len = 0; \
136 Symbol* clss_name = name(); \
137 if (clss_name != nullptr) { \
138 data = (char*)clss_name->bytes(); \
139 len = clss_name->utf8_length(); \
140 } \
141 HOTSPOT_CLASS_INITIALIZATION_##type( \
142 data, len, (void*)class_loader(), thread_type, wait); \
143 }
144
145 #else // ndef DTRACE_ENABLED
146
147 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
148 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
149
150 #endif // ndef DTRACE_ENABLED
151
152 void InlineLayoutInfo::metaspace_pointers_do(MetaspaceClosure* it) {
153 log_trace(cds)("Iter(InlineFieldInfo): %p", this);
154 it->push(&_klass);
155 }
156
157 bool InstanceKlass::_finalization_enabled = true;
158
159 static inline bool is_class_loader(const Symbol* class_name,
160 const ClassFileParser& parser) {
161 assert(class_name != nullptr, "invariant");
162
163 if (class_name == vmSymbols::java_lang_ClassLoader()) {
164 return true;
165 }
166
167 if (vmClasses::ClassLoader_klass_loaded()) {
168 const Klass* const super_klass = parser.super_klass();
169 if (super_klass != nullptr) {
170 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
171 return true;
172 }
173 }
174 }
175 return false;
176 }
177
178 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
179 return field(index).field_flags().is_null_free_inline_type();
180 }
181
182 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const {
183 if (_loadable_descriptors == nullptr) return false;
184 for (int i = 0; i < _loadable_descriptors->length(); i++) {
185 Symbol* class_name = _constants->symbol_at(_loadable_descriptors->at(i));
186 if (class_name == name) return true;
187 }
188 return false;
189 }
190
191 static inline bool is_stack_chunk_class(const Symbol* class_name,
192 const ClassLoaderData* loader_data) {
193 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
194 loader_data->is_the_null_class_loader_data());
195 }
196
197 // private: called to verify that k is a static member of this nest.
198 // We know that k is an instance class in the same package and hence the
199 // same classloader.
200 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
201 assert(!is_hidden(), "unexpected hidden class");
202 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
203 if (log_is_enabled(Trace, class, nestmates)) {
204 ResourceMark rm(current);
205 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
206 k->external_name(), this->external_name());
207 }
208 return false;
209 }
210
211 if (log_is_enabled(Trace, class, nestmates)) {
212 ResourceMark rm(current);
213 log_trace(class, nestmates)("Checking nest membership of %s in %s",
214 k->external_name(), this->external_name());
215 }
216
217 // Check for the named class in _nest_members.
218 // We don't resolve, or load, any classes.
219 for (int i = 0; i < _nest_members->length(); i++) {
220 int cp_index = _nest_members->at(i);
221 Symbol* name = _constants->klass_name_at(cp_index);
222 if (name == k->name()) {
223 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
224 return true;
225 }
226 }
227 log_trace(class, nestmates)("- class is NOT a nest member!");
228 return false;
229 }
230
231 // Called to verify that k is a permitted subclass of this class
232 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
233 Thread* current = Thread::current();
234 assert(k != nullptr, "sanity check");
235 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
236 "unexpected empty _permitted_subclasses array");
237
238 if (log_is_enabled(Trace, class, sealed)) {
239 ResourceMark rm(current);
240 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
241 k->external_name(), this->external_name());
242 }
243
244 // Check that the class and its super are in the same module.
245 if (k->module() != this->module()) {
246 ResourceMark rm(current);
247 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
248 k->external_name(), this->external_name());
249 return false;
250 }
251
252 if (!k->is_public() && !is_same_class_package(k)) {
253 ResourceMark rm(current);
254 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
255 k->external_name(), this->external_name());
256 return false;
257 }
258
259 for (int i = 0; i < _permitted_subclasses->length(); i++) {
260 int cp_index = _permitted_subclasses->at(i);
261 Symbol* name = _constants->klass_name_at(cp_index);
262 if (name == k->name()) {
263 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
264 return true;
265 }
266 }
267 log_trace(class, sealed)("- class is NOT a permitted subclass!");
268 return false;
269 }
270
271 // Return nest-host class, resolving, validating and saving it if needed.
272 // In cases where this is called from a thread that cannot do classloading
273 // (such as a native JIT thread) then we simply return null, which in turn
274 // causes the access check to return false. Such code will retry the access
275 // from a more suitable environment later. Otherwise the _nest_host is always
276 // set once this method returns.
277 // Any errors from nest-host resolution must be preserved so they can be queried
278 // from higher-level access checking code, and reported as part of access checking
279 // exceptions.
280 // VirtualMachineErrors are propagated with a null return.
281 // Under any conditions where the _nest_host can be set to non-null the resulting
282 // value of it and, if applicable, the nest host resolution/validation error,
283 // are idempotent.
284 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
285 InstanceKlass* nest_host_k = _nest_host;
286 if (nest_host_k != nullptr) {
287 return nest_host_k;
288 }
289
290 ResourceMark rm(THREAD);
291
292 // need to resolve and save our nest-host class.
293 if (_nest_host_index != 0) { // we have a real nest_host
294 // Before trying to resolve check if we're in a suitable context
295 bool can_resolve = THREAD->can_call_java();
296 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
297 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
298 this->external_name());
299 return nullptr; // sentinel to say "try again from a different context"
300 }
301
302 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
303 this->external_name(),
304 _constants->klass_name_at(_nest_host_index)->as_C_string());
305
306 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
307 if (HAS_PENDING_EXCEPTION) {
308 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
309 return nullptr; // propagate VMEs
310 }
311 stringStream ss;
312 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
313 ss.print("Nest host resolution of %s with host %s failed: ",
314 this->external_name(), target_host_class);
315 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
316 const char* msg = ss.as_string(true /* on C-heap */);
317 constantPoolHandle cph(THREAD, constants());
318 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
319 CLEAR_PENDING_EXCEPTION;
320
321 log_trace(class, nestmates)("%s", msg);
322 } else {
323 // A valid nest-host is an instance class in the current package that lists this
324 // class as a nest member. If any of these conditions are not met the class is
325 // its own nest-host.
326 const char* error = nullptr;
327
328 // JVMS 5.4.4 indicates package check comes first
329 if (is_same_class_package(k)) {
330 // Now check actual membership. We can't be a member if our "host" is
331 // not an instance class.
332 if (k->is_instance_klass()) {
333 nest_host_k = InstanceKlass::cast(k);
334 bool is_member = nest_host_k->has_nest_member(THREAD, this);
335 if (is_member) {
336 _nest_host = nest_host_k; // save resolved nest-host value
337
338 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
339 this->external_name(), k->external_name());
340 return nest_host_k;
341 } else {
342 error = "current type is not listed as a nest member";
343 }
344 } else {
345 error = "host is not an instance class";
346 }
347 } else {
348 error = "types are in different packages";
349 }
350
351 // something went wrong, so record what and log it
352 {
353 stringStream ss;
354 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
355 this->external_name(),
356 this->class_loader_data()->loader_name_and_id(),
357 k->external_name(),
358 k->class_loader_data()->loader_name_and_id(),
359 error);
360 const char* msg = ss.as_string(true /* on C-heap */);
361 constantPoolHandle cph(THREAD, constants());
362 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
363 log_trace(class, nestmates)("%s", msg);
364 }
365 }
366 } else {
367 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
368 this->external_name());
369 }
370
371 // Either not in an explicit nest, or else an error occurred, so
372 // the nest-host is set to `this`. Any thread that sees this assignment
373 // will also see any setting of nest_host_error(), if applicable.
374 return (_nest_host = this);
375 }
376
377 // Dynamic nest member support: set this class's nest host to the given class.
378 // This occurs as part of the class definition, as soon as the instanceKlass
379 // has been created and doesn't require further resolution. The code:
380 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
381 // results in:
382 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
383 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
384 // We also know the "host" is a valid nest-host in the same package so we can
385 // assert some of those facts.
386 void InstanceKlass::set_nest_host(InstanceKlass* host) {
387 assert(is_hidden(), "must be a hidden class");
388 assert(host != nullptr, "null nest host specified");
389 assert(_nest_host == nullptr, "current class has resolved nest-host");
390 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
391 nest_host_error());
392 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
393 (host->_nest_host == host), "proposed host is not a valid nest-host");
394 // Can't assert this as package is not set yet:
395 // assert(is_same_class_package(host), "proposed host is in wrong package");
396
397 if (log_is_enabled(Trace, class, nestmates)) {
398 ResourceMark rm;
399 const char* msg = "";
400 // a hidden class does not expect a statically defined nest-host
401 if (_nest_host_index > 0) {
402 msg = "(the NestHost attribute in the current class is ignored)";
403 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
404 msg = "(the NestMembers attribute in the current class is ignored)";
405 }
406 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
407 this->external_name(),
408 host->external_name(),
409 msg);
410 }
411 // set dynamic nest host
412 _nest_host = host;
413 // Record dependency to keep nest host from being unloaded before this class.
414 ClassLoaderData* this_key = class_loader_data();
415 assert(this_key != nullptr, "sanity");
416 this_key->record_dependency(host);
417 }
418
419 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
420 // or we are k's nest_host - all of which is covered by comparing the two
421 // resolved_nest_hosts.
422 // Any exceptions (i.e. VMEs) are propagated.
423 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
424
425 assert(this != k, "this should be handled by higher-level code");
426
427 // Per JVMS 5.4.4 we first resolve and validate the current class, then
428 // the target class k.
429
430 InstanceKlass* cur_host = nest_host(CHECK_false);
431 if (cur_host == nullptr) {
432 return false;
433 }
434
435 Klass* k_nest_host = k->nest_host(CHECK_false);
436 if (k_nest_host == nullptr) {
437 return false;
438 }
439
440 bool access = (cur_host == k_nest_host);
441
442 ResourceMark rm(THREAD);
443 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
444 this->external_name(),
445 access ? "" : "NOT ",
446 k->external_name());
447 return access;
448 }
449
450 const char* InstanceKlass::nest_host_error() {
451 if (_nest_host_index == 0) {
452 return nullptr;
453 } else {
454 constantPoolHandle cph(Thread::current(), constants());
455 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
456 }
457 }
458
459 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size,
460 bool use_class_space, TRAPS) throw() {
461 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD);
462 }
463
464 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
465 const int size = InstanceKlass::size(parser.vtable_size(),
466 parser.itable_size(),
467 nonstatic_oop_map_size(parser.total_oop_map_count()),
468 parser.is_interface(),
469 parser.is_inline_type());
470
471 const Symbol* const class_name = parser.class_name();
472 assert(class_name != nullptr, "invariant");
473 ClassLoaderData* loader_data = parser.loader_data();
474 assert(loader_data != nullptr, "invariant");
475
476 InstanceKlass* ik;
477 const bool use_class_space = !parser.is_interface() && !parser.is_abstract();
478
479 // Allocation
480 if (parser.is_instance_ref_klass()) {
481 // java.lang.ref.Reference
482 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser);
483 } else if (class_name == vmSymbols::java_lang_Class()) {
484 // mirror - java.lang.Class
485 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser);
486 } else if (is_stack_chunk_class(class_name, loader_data)) {
487 // stack chunk
488 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser);
489 } else if (is_class_loader(class_name, parser)) {
490 // class loader - java.lang.ClassLoader
491 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser);
492 } else if (parser.is_inline_type()) {
493 // inline type
494 ik = new (loader_data, size, use_class_space, THREAD) InlineKlass(parser);
495 } else {
496 // normal
497 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser);
498 }
499
500 // Check for pending exception before adding to the loader data and incrementing
501 // class count. Can get OOM here.
502 if (HAS_PENDING_EXCEPTION) {
503 return nullptr;
504 }
505
506 #ifdef ASSERT
507 ik->bounds_check((address) ik->start_of_vtable(), false, size);
508 ik->bounds_check((address) ik->start_of_itable(), false, size);
509 ik->bounds_check((address) ik->end_of_itable(), true, size);
510 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
511 #endif //ASSERT
512 return ik;
513 }
514
515 #ifndef PRODUCT
516 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
517 const char* bad = nullptr;
518 address end = nullptr;
519 if (addr < (address)this) {
520 bad = "before";
521 } else if (addr == (address)this) {
522 if (edge_ok) return true;
523 bad = "just before";
524 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
525 if (edge_ok) return true;
526 bad = "just after";
527 } else if (addr > end) {
528 bad = "after";
529 } else {
530 return true;
531 }
532 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
533 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
534 Verbose = WizardMode = true; this->print(); //@@
535 return false;
536 }
537 #endif //PRODUCT
538
539 // copy method ordering from resource area to Metaspace
540 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
541 if (m != nullptr) {
542 // allocate a new array and copy contents (memcpy?)
543 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
544 for (int i = 0; i < m->length(); i++) {
545 _method_ordering->at_put(i, m->at(i));
546 }
547 } else {
548 _method_ordering = Universe::the_empty_int_array();
549 }
550 }
551
552 // create a new array of vtable_indices for default methods
553 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
554 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
555 assert(default_vtable_indices() == nullptr, "only create once");
556 set_default_vtable_indices(vtable_indices);
557 return vtable_indices;
558 }
559
560
561 InstanceKlass::InstanceKlass() {
562 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
563 }
564
565 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
566 Klass(kind),
567 _nest_members(nullptr),
568 _nest_host(nullptr),
569 _permitted_subclasses(nullptr),
570 _record_components(nullptr),
571 _static_field_size(parser.static_field_size()),
572 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
573 _itable_len(parser.itable_size()),
574 _nest_host_index(0),
575 _init_state(allocated),
576 _reference_type(reference_type),
577 _init_thread(nullptr),
578 _inline_layout_info_array(nullptr),
579 _loadable_descriptors(nullptr),
580 _adr_inlineklass_fixed_block(nullptr)
581 {
582 set_vtable_length(parser.vtable_size());
583 set_access_flags(parser.access_flags());
584 if (parser.is_hidden()) set_is_hidden();
585 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
586 false));
587 if (parser.has_inline_fields()) {
588 set_has_inline_type_fields();
589 }
590
591 assert(nullptr == _methods, "underlying memory not zeroed?");
592 assert(is_instance_klass(), "is layout incorrect?");
593 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
594 }
595
596 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
597 Array<Method*>* methods) {
598 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
599 !methods->is_shared()) {
600 for (int i = 0; i < methods->length(); i++) {
601 Method* method = methods->at(i);
602 if (method == nullptr) continue; // maybe null if error processing
603 // Only want to delete methods that are not executing for RedefineClasses.
604 // The previous version will point to them so they're not totally dangling
605 assert (!method->on_stack(), "shouldn't be called with methods on stack");
606 MetadataFactory::free_metadata(loader_data, method);
607 }
608 MetadataFactory::free_array<Method*>(loader_data, methods);
609 }
610 }
611
612 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
613 const Klass* super_klass,
614 Array<InstanceKlass*>* local_interfaces,
615 Array<InstanceKlass*>* transitive_interfaces) {
616 // Only deallocate transitive interfaces if not empty, same as super class
617 // or same as local interfaces. See code in parseClassFile.
618 Array<InstanceKlass*>* ti = transitive_interfaces;
619 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
620 // check that the interfaces don't come from super class
621 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
622 InstanceKlass::cast(super_klass)->transitive_interfaces();
623 if (ti != sti && ti != nullptr && !ti->is_shared()) {
624 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
625 }
626 }
627
628 // local interfaces can be empty
629 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
630 local_interfaces != nullptr && !local_interfaces->is_shared()) {
631 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
632 }
633 }
634
635 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
636 Array<RecordComponent*>* record_components) {
637 if (record_components != nullptr && !record_components->is_shared()) {
638 for (int i = 0; i < record_components->length(); i++) {
639 RecordComponent* record_component = record_components->at(i);
640 MetadataFactory::free_metadata(loader_data, record_component);
641 }
642 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
643 }
644 }
645
646 // This function deallocates the metadata and C heap pointers that the
647 // InstanceKlass points to.
648 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
649 // Orphan the mirror first, CMS thinks it's still live.
650 if (java_mirror() != nullptr) {
651 java_lang_Class::set_klass(java_mirror(), nullptr);
652 }
653
654 // Also remove mirror from handles
655 loader_data->remove_handle(_java_mirror);
656
657 // Need to take this class off the class loader data list.
658 loader_data->remove_class(this);
659
660 // The array_klass for this class is created later, after error handling.
661 // For class redefinition, we keep the original class so this scratch class
662 // doesn't have an array class. Either way, assert that there is nothing
663 // to deallocate.
664 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
665
666 // Release C heap allocated data that this points to, which includes
667 // reference counting symbol names.
668 // Can't release the constant pool or MethodData C heap data here because the constant
669 // pool can be deallocated separately from the InstanceKlass for default methods and
670 // redefine classes. MethodData can also be released separately.
671 release_C_heap_structures(/* release_sub_metadata */ false);
672
673 deallocate_methods(loader_data, methods());
674 set_methods(nullptr);
675
676 deallocate_record_components(loader_data, record_components());
677 set_record_components(nullptr);
678
679 if (method_ordering() != nullptr &&
680 method_ordering() != Universe::the_empty_int_array() &&
681 !method_ordering()->is_shared()) {
682 MetadataFactory::free_array<int>(loader_data, method_ordering());
683 }
684 set_method_ordering(nullptr);
685
686 // default methods can be empty
687 if (default_methods() != nullptr &&
688 default_methods() != Universe::the_empty_method_array() &&
689 !default_methods()->is_shared()) {
690 MetadataFactory::free_array<Method*>(loader_data, default_methods());
691 }
692 // Do NOT deallocate the default methods, they are owned by superinterfaces.
693 set_default_methods(nullptr);
694
695 // default methods vtable indices can be empty
696 if (default_vtable_indices() != nullptr &&
697 !default_vtable_indices()->is_shared()) {
698 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
699 }
700 set_default_vtable_indices(nullptr);
701
702
703 // This array is in Klass, but remove it with the InstanceKlass since
704 // this place would be the only caller and it can share memory with transitive
705 // interfaces.
706 if (secondary_supers() != nullptr &&
707 secondary_supers() != Universe::the_empty_klass_array() &&
708 // see comments in compute_secondary_supers about the following cast
709 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
710 !secondary_supers()->is_shared()) {
711 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
712 }
713 set_secondary_supers(nullptr);
714
715 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
716 set_transitive_interfaces(nullptr);
717 set_local_interfaces(nullptr);
718
719 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
720 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
721 }
722 set_fieldinfo_stream(nullptr);
723
724 if (fields_status() != nullptr && !fields_status()->is_shared()) {
725 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
726 }
727 set_fields_status(nullptr);
728
729 if (inline_layout_info_array() != nullptr) {
730 MetadataFactory::free_array<InlineLayoutInfo>(loader_data, inline_layout_info_array());
731 }
732 set_inline_layout_info_array(nullptr);
733
734 // If a method from a redefined class is using this constant pool, don't
735 // delete it, yet. The new class's previous version will point to this.
736 if (constants() != nullptr) {
737 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
738 if (!constants()->is_shared()) {
739 MetadataFactory::free_metadata(loader_data, constants());
740 }
741 // Delete any cached resolution errors for the constant pool
742 SystemDictionary::delete_resolution_error(constants());
743
744 set_constants(nullptr);
745 }
746
747 if (inner_classes() != nullptr &&
748 inner_classes() != Universe::the_empty_short_array() &&
749 !inner_classes()->is_shared()) {
750 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
751 }
752 set_inner_classes(nullptr);
753
754 if (nest_members() != nullptr &&
755 nest_members() != Universe::the_empty_short_array() &&
756 !nest_members()->is_shared()) {
757 MetadataFactory::free_array<jushort>(loader_data, nest_members());
758 }
759 set_nest_members(nullptr);
760
761 if (permitted_subclasses() != nullptr &&
762 permitted_subclasses() != Universe::the_empty_short_array() &&
763 !permitted_subclasses()->is_shared()) {
764 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
765 }
766 set_permitted_subclasses(nullptr);
767
768 if (loadable_descriptors() != nullptr &&
769 loadable_descriptors() != Universe::the_empty_short_array() &&
770 !loadable_descriptors()->is_shared()) {
771 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors());
772 }
773 set_loadable_descriptors(nullptr);
774
775 // We should deallocate the Annotations instance if it's not in shared spaces.
776 if (annotations() != nullptr && !annotations()->is_shared()) {
777 MetadataFactory::free_metadata(loader_data, annotations());
778 }
779 set_annotations(nullptr);
780
781 SystemDictionaryShared::handle_class_unloading(this);
782
783 #if INCLUDE_CDS_JAVA_HEAP
784 if (CDSConfig::is_dumping_heap()) {
785 HeapShared::remove_scratch_objects(this);
786 }
787 #endif
788 }
789
790 bool InstanceKlass::is_record() const {
791 return _record_components != nullptr &&
792 is_final() &&
793 java_super() == vmClasses::Record_klass();
794 }
795
796 bool InstanceKlass::is_sealed() const {
797 return _permitted_subclasses != nullptr &&
798 _permitted_subclasses != Universe::the_empty_short_array();
799 }
800
801 bool InstanceKlass::should_be_initialized() const {
802 return !is_initialized();
803 }
804
805 klassItable InstanceKlass::itable() const {
806 return klassItable(const_cast<InstanceKlass*>(this));
807 }
808
809 // JVMTI spec thinks there are signers and protection domain in the
810 // instanceKlass. These accessors pretend these fields are there.
811 // The hprof specification also thinks these fields are in InstanceKlass.
812 oop InstanceKlass::protection_domain() const {
813 // return the protection_domain from the mirror
814 return java_lang_Class::protection_domain(java_mirror());
815 }
816
817 objArrayOop InstanceKlass::signers() const {
818 // return the signers from the mirror
819 return java_lang_Class::signers(java_mirror());
820 }
821
822 oop InstanceKlass::init_lock() const {
823 // return the init lock from the mirror
824 oop lock = java_lang_Class::init_lock(java_mirror());
825 // Prevent reordering with any access of initialization state
826 OrderAccess::loadload();
827 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state
828 "only fully initialized state can have a null lock");
829 return lock;
830 }
831
832 // Set the initialization lock to null so the object can be GC'ed. Any racing
833 // threads to get this lock will see a null lock and will not lock.
834 // That's okay because they all check for initialized state after getting
835 // the lock and return.
836 void InstanceKlass::fence_and_clear_init_lock() {
837 // make sure previous stores are all done, notably the init_state.
838 OrderAccess::storestore();
839 java_lang_Class::clear_init_lock(java_mirror());
840 assert(!is_not_initialized(), "class must be initialized now");
841 }
842
843
844 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
845 // process. The step comments refers to the procedure described in that section.
846 // Note: implementation moved to static method to expose the this pointer.
847 void InstanceKlass::initialize(TRAPS) {
848 if (this->should_be_initialized()) {
849 initialize_impl(CHECK);
850 // Note: at this point the class may be initialized
851 // OR it may be in the state of being initialized
852 // in case of recursive initialization!
853 } else {
854 assert(is_initialized(), "sanity check");
855 }
856 }
857
858
859 bool InstanceKlass::verify_code(TRAPS) {
860 // 1) Verify the bytecodes
861 return Verifier::verify(this, should_verify_class(), THREAD);
862 }
863
864 void InstanceKlass::link_class(TRAPS) {
865 assert(is_loaded(), "must be loaded");
866 if (!is_linked()) {
867 link_class_impl(CHECK);
868 }
869 }
870
871 // Called to verify that a class can link during initialization, without
872 // throwing a VerifyError.
873 bool InstanceKlass::link_class_or_fail(TRAPS) {
874 assert(is_loaded(), "must be loaded");
875 if (!is_linked()) {
876 link_class_impl(CHECK_false);
877 }
878 return is_linked();
879 }
880
881 bool InstanceKlass::link_class_impl(TRAPS) {
882 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) {
883 // This is for CDS static dump only -- we use the in_error_state to indicate that
884 // the class has failed verification. Throwing the NoClassDefFoundError here is just
885 // a convenient way to stop repeat attempts to verify the same (bad) class.
886 //
887 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
888 // if we are executing Java code. This is not a problem for CDS dumping phase since
889 // it doesn't execute any Java code.
890 ResourceMark rm(THREAD);
891 Exceptions::fthrow(THREAD_AND_LOCATION,
892 vmSymbols::java_lang_NoClassDefFoundError(),
893 "Class %s, or one of its supertypes, failed class initialization",
894 external_name());
895 return false;
896 }
897 // return if already verified
898 if (is_linked()) {
899 return true;
900 }
901
902 // Timing
903 // timer handles recursion
904 JavaThread* jt = THREAD;
905
906 // link super class before linking this class
907 Klass* super_klass = super();
908 if (super_klass != nullptr) {
909 if (super_klass->is_interface()) { // check if super class is an interface
910 ResourceMark rm(THREAD);
911 Exceptions::fthrow(
912 THREAD_AND_LOCATION,
913 vmSymbols::java_lang_IncompatibleClassChangeError(),
914 "class %s has interface %s as super class",
915 external_name(),
916 super_klass->external_name()
917 );
918 return false;
919 }
920
921 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
922 ik_super->link_class_impl(CHECK_false);
923 }
924
925 // link all interfaces implemented by this class before linking this class
926 Array<InstanceKlass*>* interfaces = local_interfaces();
927 int num_interfaces = interfaces->length();
928 for (int index = 0; index < num_interfaces; index++) {
929 InstanceKlass* interk = interfaces->at(index);
930 interk->link_class_impl(CHECK_false);
931 }
932
933
934 // If a class declares a method that uses an inline class as an argument
935 // type or return inline type, this inline class must be loaded during the
936 // linking of this class because size and properties of the inline class
937 // must be known in order to be able to perform inline type optimizations.
938 // The implementation below is an approximation of this rule, the code
939 // iterates over all methods of the current class (including overridden
940 // methods), not only the methods declared by this class. This
941 // approximation makes the code simpler, and doesn't change the semantic
942 // because classes declaring methods overridden by the current class are
943 // linked (and have performed their own pre-loading) before the linking
944 // of the current class.
945
946
947 // Note:
948 // Inline class types are loaded during
949 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
950 // Inline class types used as element types for array creation
951 // are not pre-loaded. Their loading is triggered by either anewarray
952 // or multianewarray bytecodes.
953
954 // Could it be possible to do the following processing only if the
955 // class uses inline types?
956 if (EnableValhalla) {
957 ResourceMark rm(THREAD);
958 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
959 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) {
960 Symbol* sig = fs.signature();
961 TempNewSymbol s = Signature::strip_envelope(sig);
962 if (s != name()) {
963 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());
964 Klass* klass = SystemDictionary::resolve_or_fail(s,
965 Handle(THREAD, class_loader()), Handle(THREAD, protection_domain()), true,
966 CHECK_false);
967 if (HAS_PENDING_EXCEPTION) {
968 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s",
969 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string());
970 return false; // Exception is still pending
971 }
972 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded",
973 s->as_C_string(), name()->as_C_string());
974 assert(klass != nullptr, "Sanity check");
975 if (klass->is_abstract()) {
976 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
977 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class",
978 name()->as_C_string(),
979 InstanceKlass::cast(klass)->external_name()), false);
980 }
981 if (!klass->is_inline_klass()) {
982 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
983 err_msg("class %s expects class %s to be a value class but it is an identity class",
984 name()->as_C_string(), klass->external_name()), false);
985 }
986 InlineKlass* vk = InlineKlass::cast(klass);
987 if (!vk->is_implicitly_constructible()) {
988 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(),
989 err_msg("class %s is not implicitly constructible and it is used in a null restricted static field (not supported)",
990 klass->external_name()), false);
991 }
992 // the inline_type_field_klasses_array might have been loaded with CDS, so update only if not already set and check consistency
993 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
994 if (li->klass() == nullptr) {
995 li->set_klass(InlineKlass::cast(vk));
996 li->set_kind(LayoutKind::REFERENCE);
997 }
998 assert(get_inline_type_field_klass(fs.index()) == vk, "Must match");
999 } else {
1000 InlineLayoutInfo* li = inline_layout_info_adr(fs.index());
1001 if (li->klass() == nullptr) {
1002 li->set_klass(InlineKlass::cast(this));
1003 li->set_kind(LayoutKind::REFERENCE);
1004 }
1005 assert(get_inline_type_field_klass(fs.index()) == this, "Must match");
1006 }
1007 }
1008 }
1009
1010 // Aggressively preloading all classes from the LoadableDescriptors attribute
1011 if (loadable_descriptors() != nullptr) {
1012 HandleMark hm(THREAD);
1013 for (int i = 0; i < loadable_descriptors()->length(); i++) {
1014 Symbol* sig = constants()->symbol_at(loadable_descriptors()->at(i));
1015 if (!Signature::has_envelope(sig)) continue;
1016 TempNewSymbol class_name = Signature::strip_envelope(sig);
1017 if (class_name == name()) continue;
1018 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());
1019 oop loader = class_loader();
1020 oop protection_domain = this->protection_domain();
1021 Klass* klass = SystemDictionary::resolve_or_null(class_name,
1022 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD);
1023 if (HAS_PENDING_EXCEPTION) {
1024 CLEAR_PENDING_EXCEPTION;
1025 }
1026 if (klass != nullptr) {
1027 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());
1028 if (!klass->is_inline_klass()) {
1029 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning
1030 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());
1031 }
1032 } else {
1033 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());
1034 }
1035 }
1036 }
1037 }
1038
1039 // in case the class is linked in the process of linking its superclasses
1040 if (is_linked()) {
1041 return true;
1042 }
1043
1044 // trace only the link time for this klass that includes
1045 // the verification time
1046 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
1047 ClassLoader::perf_class_link_selftime(),
1048 ClassLoader::perf_classes_linked(),
1049 jt->get_thread_stat()->perf_recursion_counts_addr(),
1050 jt->get_thread_stat()->perf_timers_addr(),
1051 PerfClassTraceTime::CLASS_LINK);
1052
1053 // verification & rewriting
1054 {
1055 HandleMark hm(THREAD);
1056 Handle h_init_lock(THREAD, init_lock());
1057 ObjectLocker ol(h_init_lock, jt);
1058 // rewritten will have been set if loader constraint error found
1059 // on an earlier link attempt
1060 // don't verify or rewrite if already rewritten
1061 //
1062
1063 if (!is_linked()) {
1064 if (!is_rewritten()) {
1065 if (is_shared()) {
1066 assert(!verified_at_dump_time(), "must be");
1067 }
1068 {
1069 bool verify_ok = verify_code(THREAD);
1070 if (!verify_ok) {
1071 return false;
1072 }
1073 }
1074
1075 // Just in case a side-effect of verify linked this class already
1076 // (which can sometimes happen since the verifier loads classes
1077 // using custom class loaders, which are free to initialize things)
1078 if (is_linked()) {
1079 return true;
1080 }
1081
1082 // also sets rewritten
1083 rewrite_class(CHECK_false);
1084 } else if (is_shared()) {
1085 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1086 }
1087
1088 // relocate jsrs and link methods after they are all rewritten
1089 link_methods(CHECK_false);
1090
1091 // Initialize the vtable and interface table after
1092 // methods have been rewritten since rewrite may
1093 // fabricate new Method*s.
1094 // also does loader constraint checking
1095 //
1096 // initialize_vtable and initialize_itable need to be rerun
1097 // for a shared class if
1098 // 1) the class is loaded by custom class loader or
1099 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1100 // 3) the class was not verified during dump time
1101 bool need_init_table = true;
1102 if (is_shared() && verified_at_dump_time() &&
1103 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1104 need_init_table = false;
1105 }
1106 if (need_init_table) {
1107 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1108 itable().initialize_itable_and_check_constraints(CHECK_false);
1109 }
1110 #ifdef ASSERT
1111 vtable().verify(tty, true);
1112 // In case itable verification is ever added.
1113 // itable().verify(tty, true);
1114 #endif
1115 if (Universe::is_fully_initialized()) {
1116 DeoptimizationScope deopt_scope;
1117 {
1118 // Now mark all code that assumes the class is not linked.
1119 // Set state under the Compile_lock also.
1120 MutexLocker ml(THREAD, Compile_lock);
1121
1122 set_init_state(linked);
1123 CodeCache::mark_dependents_on(&deopt_scope, this);
1124 }
1125 // Perform the deopt handshake outside Compile_lock.
1126 deopt_scope.deoptimize_marked();
1127 } else {
1128 set_init_state(linked);
1129 }
1130 if (JvmtiExport::should_post_class_prepare()) {
1131 JvmtiExport::post_class_prepare(THREAD, this);
1132 }
1133 }
1134 }
1135 return true;
1136 }
1137
1138 // Rewrite the byte codes of all of the methods of a class.
1139 // The rewriter must be called exactly once. Rewriting must happen after
1140 // verification but before the first method of the class is executed.
1141 void InstanceKlass::rewrite_class(TRAPS) {
1142 assert(is_loaded(), "must be loaded");
1143 if (is_rewritten()) {
1144 assert(is_shared(), "rewriting an unshared class?");
1145 return;
1146 }
1147 Rewriter::rewrite(this, CHECK);
1148 set_rewritten();
1149 }
1150
1151 // Now relocate and link method entry points after class is rewritten.
1152 // This is outside is_rewritten flag. In case of an exception, it can be
1153 // executed more than once.
1154 void InstanceKlass::link_methods(TRAPS) {
1155 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time());
1156
1157 int len = methods()->length();
1158 for (int i = len-1; i >= 0; i--) {
1159 methodHandle m(THREAD, methods()->at(i));
1160
1161 // Set up method entry points for compiler and interpreter .
1162 m->link_method(m, CHECK);
1163 }
1164 }
1165
1166 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1167 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1168 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1169 for (int i = 0; i < local_interfaces()->length(); ++i) {
1170 InstanceKlass* ik = local_interfaces()->at(i);
1171
1172 // Initialization is depth first search ie. we start with top of the inheritance tree
1173 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1174 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1175 if (ik->has_nonstatic_concrete_methods()) {
1176 ik->initialize_super_interfaces(CHECK);
1177 }
1178
1179 // Only initialize() interfaces that "declare" concrete methods.
1180 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1181 ik->initialize(CHECK);
1182 }
1183 }
1184 }
1185
1186 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1187 static InitializationErrorTable* _initialization_error_table;
1188
1189 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1190 // Create the same exception with a message indicating the thread name,
1191 // and the StackTraceElements.
1192 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1193 ResourceMark rm(current);
1194 if (init_error.is_null()) {
1195 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1196
1197 // We failed to create the new exception, most likely due to either out-of-memory or
1198 // a stackoverflow error. If the original exception was either of those then we save
1199 // the shared, pre-allocated, stackless, instance of that exception.
1200 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1201 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1202 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1203 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1204 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1205 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1206 } else {
1207 return;
1208 }
1209 }
1210
1211 MutexLocker ml(current, ClassInitError_lock);
1212 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1213 bool created;
1214 if (_initialization_error_table == nullptr) {
1215 _initialization_error_table = new (mtClass) InitializationErrorTable();
1216 }
1217 _initialization_error_table->put_if_absent(this, elem, &created);
1218 assert(created, "Initialization is single threaded");
1219 log_trace(class, init)("Initialization error added for class %s", external_name());
1220 }
1221
1222 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1223 MutexLocker ml(current, ClassInitError_lock);
1224 if (_initialization_error_table == nullptr) {
1225 return nullptr;
1226 }
1227 OopHandle* h = _initialization_error_table->get(this);
1228 return (h != nullptr) ? h->resolve() : nullptr;
1229 }
1230
1231 // Need to remove entries for unloaded classes.
1232 void InstanceKlass::clean_initialization_error_table() {
1233 struct InitErrorTableCleaner {
1234 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1235 if (!ik->is_loader_alive()) {
1236 h.release(Universe::vm_global());
1237 return true;
1238 } else {
1239 return false;
1240 }
1241 }
1242 };
1243
1244 assert_locked_or_safepoint(ClassInitError_lock);
1245 InitErrorTableCleaner cleaner;
1246 if (_initialization_error_table != nullptr) {
1247 _initialization_error_table->unlink(&cleaner);
1248 }
1249 }
1250
1251 void InstanceKlass::initialize_impl(TRAPS) {
1252 HandleMark hm(THREAD);
1253
1254 // Make sure klass is linked (verified) before initialization
1255 // A class could already be verified, since it has been reflected upon.
1256 link_class(CHECK);
1257
1258 DTRACE_CLASSINIT_PROBE(required, -1);
1259
1260 bool wait = false;
1261
1262 JavaThread* jt = THREAD;
1263
1264 bool debug_logging_enabled = log_is_enabled(Debug, class, init);
1265
1266 // refer to the JVM book page 47 for description of steps
1267 // Step 1
1268 {
1269 Handle h_init_lock(THREAD, init_lock());
1270 ObjectLocker ol(h_init_lock, jt);
1271
1272 // Step 2
1273 // If we were to use wait() instead of waitInterruptibly() then
1274 // we might end up throwing IE from link/symbol resolution sites
1275 // that aren't expected to throw. This would wreak havoc. See 6320309.
1276 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1277 if (debug_logging_enabled) {
1278 ResourceMark rm(jt);
1279 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
1280 jt->name(), external_name(), init_thread_name());
1281 }
1282 wait = true;
1283 jt->set_class_to_be_initialized(this);
1284 ol.wait_uninterruptibly(jt);
1285 jt->set_class_to_be_initialized(nullptr);
1286 }
1287
1288 // Step 3
1289 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1290 if (debug_logging_enabled) {
1291 ResourceMark rm(jt);
1292 log_debug(class, init)("Thread \"%s\" recursively initializing %s",
1293 jt->name(), external_name());
1294 }
1295 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1296 return;
1297 }
1298
1299 // Step 4
1300 if (is_initialized()) {
1301 if (debug_logging_enabled) {
1302 ResourceMark rm(jt);
1303 log_debug(class, init)("Thread \"%s\" found %s already initialized",
1304 jt->name(), external_name());
1305 }
1306 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1307 return;
1308 }
1309
1310 // Step 5
1311 if (is_in_error_state()) {
1312 if (debug_logging_enabled) {
1313 ResourceMark rm(jt);
1314 log_debug(class, init)("Thread \"%s\" found %s is in error state",
1315 jt->name(), external_name());
1316 }
1317
1318 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1319 ResourceMark rm(THREAD);
1320 Handle cause(THREAD, get_initialization_error(THREAD));
1321
1322 stringStream ss;
1323 ss.print("Could not initialize class %s", external_name());
1324 if (cause.is_null()) {
1325 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1326 } else {
1327 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1328 ss.as_string(), cause);
1329 }
1330 } else {
1331
1332 // Step 6
1333 set_init_state(being_initialized);
1334 set_init_thread(jt);
1335 if (debug_logging_enabled) {
1336 ResourceMark rm(jt);
1337 log_debug(class, init)("Thread \"%s\" is initializing %s",
1338 jt->name(), external_name());
1339 }
1340 }
1341 }
1342
1343 // Pre-allocating an instance of the default value
1344 if (is_inline_klass()) {
1345 InlineKlass* vk = InlineKlass::cast(this);
1346 oop val = vk->allocate_instance(THREAD);
1347 if (HAS_PENDING_EXCEPTION) {
1348 Handle e(THREAD, PENDING_EXCEPTION);
1349 CLEAR_PENDING_EXCEPTION;
1350 {
1351 EXCEPTION_MARK;
1352 add_initialization_error(THREAD, e);
1353 // Locks object, set state, and notify all waiting threads
1354 set_initialization_state_and_notify(initialization_error, THREAD);
1355 CLEAR_PENDING_EXCEPTION;
1356 }
1357 THROW_OOP(e());
1358 }
1359 vk->set_default_value(val);
1360 if (vk->has_nullable_layout()) {
1361 val = vk->allocate_instance(THREAD);
1362 if (HAS_PENDING_EXCEPTION) {
1363 Handle e(THREAD, PENDING_EXCEPTION);
1364 CLEAR_PENDING_EXCEPTION;
1365 {
1366 EXCEPTION_MARK;
1367 add_initialization_error(THREAD, e);
1368 // Locks object, set state, and notify all waiting threads
1369 set_initialization_state_and_notify(initialization_error, THREAD);
1370 CLEAR_PENDING_EXCEPTION;
1371 }
1372 THROW_OOP(e());
1373 }
1374 vk->set_null_reset_value(val);
1375 }
1376 }
1377
1378 // Step 7
1379 // Next, if C is a class rather than an interface, initialize it's super class and super
1380 // interfaces.
1381 if (!is_interface()) {
1382 Klass* super_klass = super();
1383 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1384 super_klass->initialize(THREAD);
1385 }
1386 // If C implements any interface that declares a non-static, concrete method,
1387 // the initialization of C triggers initialization of its super interfaces.
1388 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1389 // having a superinterface that declares, non-static, concrete methods
1390 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1391 initialize_super_interfaces(THREAD);
1392 }
1393
1394 // If any exceptions, complete abruptly, throwing the same exception as above.
1395 if (HAS_PENDING_EXCEPTION) {
1396 Handle e(THREAD, PENDING_EXCEPTION);
1397 CLEAR_PENDING_EXCEPTION;
1398 {
1399 EXCEPTION_MARK;
1400 add_initialization_error(THREAD, e);
1401 // Locks object, set state, and notify all waiting threads
1402 set_initialization_state_and_notify(initialization_error, THREAD);
1403 CLEAR_PENDING_EXCEPTION;
1404 }
1405 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1406 THROW_OOP(e());
1407 }
1408 }
1409
1410 // Step 8
1411 // Initialize classes of inline fields
1412 if (EnableValhalla) {
1413 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1414 if (fs.is_null_free_inline_type()) {
1415
1416 // inline type field klass array entries must have alreadyt been filed at load time or link time
1417 Klass* klass = get_inline_type_field_klass(fs.index());
1418
1419 InstanceKlass::cast(klass)->initialize(THREAD);
1420 if (fs.access_flags().is_static()) {
1421 if (java_mirror()->obj_field(fs.offset()) == nullptr) {
1422 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value());
1423 }
1424 }
1425
1426 if (HAS_PENDING_EXCEPTION) {
1427 Handle e(THREAD, PENDING_EXCEPTION);
1428 CLEAR_PENDING_EXCEPTION;
1429 {
1430 EXCEPTION_MARK;
1431 add_initialization_error(THREAD, e);
1432 // Locks object, set state, and notify all waiting threads
1433 set_initialization_state_and_notify(initialization_error, THREAD);
1434 CLEAR_PENDING_EXCEPTION;
1435 }
1436 THROW_OOP(e());
1437 }
1438 }
1439 }
1440 }
1441
1442
1443 // Step 9
1444 {
1445 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1446 if (class_initializer() != nullptr) {
1447 // Timer includes any side effects of class initialization (resolution,
1448 // etc), but not recursive entry into call_class_initializer().
1449 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1450 ClassLoader::perf_class_init_selftime(),
1451 ClassLoader::perf_classes_inited(),
1452 jt->get_thread_stat()->perf_recursion_counts_addr(),
1453 jt->get_thread_stat()->perf_timers_addr(),
1454 PerfClassTraceTime::CLASS_CLINIT);
1455 call_class_initializer(THREAD);
1456 } else {
1457 // The elapsed time is so small it's not worth counting.
1458 if (UsePerfData) {
1459 ClassLoader::perf_classes_inited()->inc();
1460 }
1461 call_class_initializer(THREAD);
1462 }
1463 }
1464
1465 // Step 10
1466 if (!HAS_PENDING_EXCEPTION) {
1467 set_initialization_state_and_notify(fully_initialized, CHECK);
1468 debug_only(vtable().verify(tty, true);)
1469 }
1470 else {
1471 // Step 11 and 12
1472 Handle e(THREAD, PENDING_EXCEPTION);
1473 CLEAR_PENDING_EXCEPTION;
1474 // JVMTI has already reported the pending exception
1475 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1476 JvmtiExport::clear_detected_exception(jt);
1477 {
1478 EXCEPTION_MARK;
1479 add_initialization_error(THREAD, e);
1480 set_initialization_state_and_notify(initialization_error, THREAD);
1481 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1482 // JVMTI has already reported the pending exception
1483 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1484 JvmtiExport::clear_detected_exception(jt);
1485 }
1486 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1487 if (e->is_a(vmClasses::Error_klass())) {
1488 THROW_OOP(e());
1489 } else {
1490 JavaCallArguments args(e);
1491 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1492 vmSymbols::throwable_void_signature(),
1493 &args);
1494 }
1495 }
1496 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1497 }
1498
1499
1500 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1501 Handle h_init_lock(THREAD, init_lock());
1502 if (h_init_lock() != nullptr) {
1503 ObjectLocker ol(h_init_lock, THREAD);
1504 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1505 set_init_state(state);
1506 fence_and_clear_init_lock();
1507 ol.notify_all(CHECK);
1508 } else {
1509 assert(h_init_lock() != nullptr, "The initialization state should never be set twice");
1510 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1511 set_init_state(state);
1512 }
1513 }
1514
1515 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1516 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1517 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1518 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1519
1520 DeoptimizationScope deopt_scope;
1521 {
1522 MutexLocker ml(current, Compile_lock);
1523
1524 set_init_state(InstanceKlass::loaded);
1525 // make sure init_state store is already done.
1526 // The compiler reads the hierarchy outside of the Compile_lock.
1527 // Access ordering is used to add to hierarchy.
1528
1529 // Link into hierarchy.
1530 append_to_sibling_list(); // add to superklass/sibling list
1531 process_interfaces(); // handle all "implements" declarations
1532
1533 // Now mark all code that depended on old class hierarchy.
1534 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1535 if (Universe::is_fully_initialized()) {
1536 CodeCache::mark_dependents_on(&deopt_scope, this);
1537 }
1538 }
1539 // Perform the deopt handshake outside Compile_lock.
1540 deopt_scope.deoptimize_marked();
1541 }
1542
1543
1544 InstanceKlass* InstanceKlass::implementor() const {
1545 InstanceKlass* volatile* ik = adr_implementor();
1546 if (ik == nullptr) {
1547 return nullptr;
1548 } else {
1549 // This load races with inserts, and therefore needs acquire.
1550 InstanceKlass* ikls = Atomic::load_acquire(ik);
1551 if (ikls != nullptr && !ikls->is_loader_alive()) {
1552 return nullptr; // don't return unloaded class
1553 } else {
1554 return ikls;
1555 }
1556 }
1557 }
1558
1559
1560 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1561 assert_locked_or_safepoint(Compile_lock);
1562 assert(is_interface(), "not interface");
1563 InstanceKlass* volatile* addr = adr_implementor();
1564 assert(addr != nullptr, "null addr");
1565 if (addr != nullptr) {
1566 Atomic::release_store(addr, ik);
1567 }
1568 }
1569
1570 int InstanceKlass::nof_implementors() const {
1571 InstanceKlass* ik = implementor();
1572 if (ik == nullptr) {
1573 return 0;
1574 } else if (ik != this) {
1575 return 1;
1576 } else {
1577 return 2;
1578 }
1579 }
1580
1581 // The embedded _implementor field can only record one implementor.
1582 // When there are more than one implementors, the _implementor field
1583 // is set to the interface Klass* itself. Following are the possible
1584 // values for the _implementor field:
1585 // null - no implementor
1586 // implementor Klass* - one implementor
1587 // self - more than one implementor
1588 //
1589 // The _implementor field only exists for interfaces.
1590 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1591 if (Universe::is_fully_initialized()) {
1592 assert_lock_strong(Compile_lock);
1593 }
1594 assert(is_interface(), "not interface");
1595 // Filter out my subinterfaces.
1596 // (Note: Interfaces are never on the subklass list.)
1597 if (ik->is_interface()) return;
1598
1599 // Filter out subclasses whose supers already implement me.
1600 // (Note: CHA must walk subclasses of direct implementors
1601 // in order to locate indirect implementors.)
1602 InstanceKlass* super_ik = ik->java_super();
1603 if (super_ik != nullptr && super_ik->implements_interface(this))
1604 // We only need to check one immediate superclass, since the
1605 // implements_interface query looks at transitive_interfaces.
1606 // Any supers of the super have the same (or fewer) transitive_interfaces.
1607 return;
1608
1609 InstanceKlass* iklass = implementor();
1610 if (iklass == nullptr) {
1611 set_implementor(ik);
1612 } else if (iklass != this && iklass != ik) {
1613 // There is already an implementor. Use itself as an indicator of
1614 // more than one implementors.
1615 set_implementor(this);
1616 }
1617
1618 // The implementor also implements the transitive_interfaces
1619 for (int index = 0; index < local_interfaces()->length(); index++) {
1620 local_interfaces()->at(index)->add_implementor(ik);
1621 }
1622 }
1623
1624 void InstanceKlass::init_implementor() {
1625 if (is_interface()) {
1626 set_implementor(nullptr);
1627 }
1628 }
1629
1630
1631 void InstanceKlass::process_interfaces() {
1632 // link this class into the implementors list of every interface it implements
1633 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1634 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1635 InstanceKlass* interf = local_interfaces()->at(i);
1636 assert(interf->is_interface(), "expected interface");
1637 interf->add_implementor(this);
1638 }
1639 }
1640
1641 bool InstanceKlass::can_be_primary_super_slow() const {
1642 if (is_interface())
1643 return false;
1644 else
1645 return Klass::can_be_primary_super_slow();
1646 }
1647
1648 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1649 Array<InstanceKlass*>* transitive_interfaces) {
1650 // The secondaries are the implemented interfaces.
1651 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1652 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1653 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces;
1654 int num_secondaries = num_extra_slots + interfaces->length();
1655 if (num_secondaries == 0) {
1656 // Must share this for correct bootstrapping!
1657 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap());
1658 return nullptr;
1659 } else if (num_extra_slots == 0) {
1660 // The secondary super list is exactly the same as the transitive interfaces, so
1661 // let's use it instead of making a copy.
1662 // Redefine classes has to be careful not to delete this!
1663 if (!UseSecondarySupersTable) {
1664 set_secondary_supers(interfaces);
1665 return nullptr;
1666 } else if (num_extra_slots == 0 && interfaces->length() <= 1) {
1667 // We will reuse the transitive interfaces list if we're certain
1668 // it's in hash order.
1669 uintx bitmap = compute_secondary_supers_bitmap(interfaces);
1670 set_secondary_supers(interfaces, bitmap);
1671 return nullptr;
1672 }
1673 // ... fall through if that didn't work.
1674 }
1675 // Copy transitive interfaces to a temporary growable array to be constructed
1676 // into the secondary super list with extra slots.
1677 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1678 for (int i = 0; i < interfaces->length(); i++) {
1679 secondaries->push(interfaces->at(i));
1680 }
1681 return secondaries;
1682 }
1683
1684 bool InstanceKlass::implements_interface(Klass* k) const {
1685 if (this == k) return true;
1686 assert(k->is_interface(), "should be an interface class");
1687 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1688 if (transitive_interfaces()->at(i) == k) {
1689 return true;
1690 }
1691 }
1692 return false;
1693 }
1694
1695 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1696 // Verify direct super interface
1697 if (this == k) return true;
1698 assert(k->is_interface(), "should be an interface class");
1699 for (int i = 0; i < local_interfaces()->length(); i++) {
1700 if (local_interfaces()->at(i) == k) {
1701 return true;
1702 }
1703 }
1704 return false;
1705 }
1706
1707 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1708 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1709 size_t size = objArrayOopDesc::object_size(length);
1710 ArrayKlass* ak = array_klass(n, CHECK_NULL);
1711 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1712 /* do_zero */ true, CHECK_NULL);
1713 return o;
1714 }
1715
1716 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1717 if (TraceFinalizerRegistration) {
1718 tty->print("Registered ");
1719 i->print_value_on(tty);
1720 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1721 }
1722 instanceHandle h_i(THREAD, i);
1723 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1724 JavaValue result(T_VOID);
1725 JavaCallArguments args(h_i);
1726 methodHandle mh(THREAD, Universe::finalizer_register_method());
1727 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1728 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1729 return h_i();
1730 }
1731
1732 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1733 assert(!is_abstract() && !is_interface(), "Should not create this object");
1734 size_t size = size_helper(); // Query before forming handle.
1735 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1736 }
1737
1738 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1739 Klass* k = java_lang_Class::as_Klass(java_class);
1740 if (k == nullptr) {
1741 ResourceMark rm(THREAD);
1742 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1743 }
1744 InstanceKlass* ik = cast(k);
1745 ik->check_valid_for_instantiation(false, CHECK_NULL);
1746 ik->initialize(CHECK_NULL);
1747 return ik->allocate_instance(THREAD);
1748 }
1749
1750 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1751 return instanceHandle(THREAD, allocate_instance(THREAD));
1752 }
1753
1754 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1755 if (is_interface() || is_abstract()) {
1756 ResourceMark rm(THREAD);
1757 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1758 : vmSymbols::java_lang_InstantiationException(), external_name());
1759 }
1760 if (this == vmClasses::Class_klass()) {
1761 ResourceMark rm(THREAD);
1762 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1763 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1764 }
1765 }
1766
1767 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) {
1768 // Need load-acquire for lock-free read
1769 if (array_klasses_acquire() == nullptr) {
1770
1771 // Recursively lock array allocation
1772 RecursiveLocker rl(MultiArray_lock, THREAD);
1773
1774 // Check if another thread created the array klass while we were waiting for the lock.
1775 if (array_klasses() == nullptr) {
1776 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, false, CHECK_NULL);
1777 // use 'release' to pair with lock-free load
1778 release_set_array_klasses(k);
1779 }
1780 }
1781
1782 // array_klasses() will always be set at this point
1783 ArrayKlass* ak = array_klasses();
1784 assert(ak != nullptr, "should be set");
1785 return ak->array_klass(n, THREAD);
1786 }
1787
1788 ArrayKlass* InstanceKlass::array_klass_or_null(int n) {
1789 // Need load-acquire for lock-free read
1790 ArrayKlass* ak = array_klasses_acquire();
1791 if (ak == nullptr) {
1792 return nullptr;
1793 } else {
1794 return ak->array_klass_or_null(n);
1795 }
1796 }
1797
1798 ArrayKlass* InstanceKlass::array_klass(TRAPS) {
1799 return array_klass(1, THREAD);
1800 }
1801
1802 ArrayKlass* InstanceKlass::array_klass_or_null() {
1803 return array_klass_or_null(1);
1804 }
1805
1806 static int call_class_initializer_counter = 0; // for debugging
1807
1808 Method* InstanceKlass::class_initializer() const {
1809 Method* clinit = find_method(
1810 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1811 if (clinit != nullptr && clinit->is_class_initializer()) {
1812 return clinit;
1813 }
1814 return nullptr;
1815 }
1816
1817 void InstanceKlass::call_class_initializer(TRAPS) {
1818 if (ReplayCompiles &&
1819 (ReplaySuppressInitializers == 1 ||
1820 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1821 // Hide the existence of the initializer for the purpose of replaying the compile
1822 return;
1823 }
1824
1825 #if INCLUDE_CDS
1826 // This is needed to ensure the consistency of the archived heap objects.
1827 if (has_archived_enum_objs()) {
1828 assert(is_shared(), "must be");
1829 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK);
1830 if (initialized) {
1831 return;
1832 }
1833 }
1834 #endif
1835
1836 methodHandle h_method(THREAD, class_initializer());
1837 assert(!is_initialized(), "we cannot initialize twice");
1838 LogTarget(Info, class, init) lt;
1839 if (lt.is_enabled()) {
1840 ResourceMark rm(THREAD);
1841 LogStream ls(lt);
1842 ls.print("%d Initializing ", call_class_initializer_counter++);
1843 name()->print_value_on(&ls);
1844 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
1845 h_method() == nullptr ? "(no method)" : "", p2i(this),
1846 THREAD->name());
1847 }
1848 if (h_method() != nullptr) {
1849 JavaCallArguments args; // No arguments
1850 JavaValue result(T_VOID);
1851 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1852 }
1853 }
1854
1855
1856 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1857 InterpreterOopMap* entry_for) {
1858 // Lazily create the _oop_map_cache at first request.
1859 // Load_acquire is needed to safely get instance published with CAS by another thread.
1860 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1861 if (oop_map_cache == nullptr) {
1862 // Try to install new instance atomically.
1863 oop_map_cache = new OopMapCache();
1864 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache);
1865 if (other != nullptr) {
1866 // Someone else managed to install before us, ditch local copy and use the existing one.
1867 delete oop_map_cache;
1868 oop_map_cache = other;
1869 }
1870 }
1871 // _oop_map_cache is constant after init; lookup below does its own locking.
1872 oop_map_cache->lookup(method, bci, entry_for);
1873 }
1874
1875
1876 FieldInfo InstanceKlass::field(int index) const {
1877 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1878 if (fs.index() == index) {
1879 return fs.to_FieldInfo();
1880 }
1881 }
1882 fatal("Field not found");
1883 return FieldInfo();
1884 }
1885
1886 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1887 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1888 Symbol* f_name = fs.name();
1889 Symbol* f_sig = fs.signature();
1890 if (f_name == name && f_sig == sig) {
1891 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1892 return true;
1893 }
1894 }
1895 return false;
1896 }
1897
1898
1899 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1900 const int n = local_interfaces()->length();
1901 for (int i = 0; i < n; i++) {
1902 Klass* intf1 = local_interfaces()->at(i);
1903 assert(intf1->is_interface(), "just checking type");
1904 // search for field in current interface
1905 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1906 assert(fd->is_static(), "interface field must be static");
1907 return intf1;
1908 }
1909 // search for field in direct superinterfaces
1910 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1911 if (intf2 != nullptr) return intf2;
1912 }
1913 // otherwise field lookup fails
1914 return nullptr;
1915 }
1916
1917
1918 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1919 // search order according to newest JVM spec (5.4.3.2, p.167).
1920 // 1) search for field in current klass
1921 if (find_local_field(name, sig, fd)) {
1922 return const_cast<InstanceKlass*>(this);
1923 }
1924 // 2) search for field recursively in direct superinterfaces
1925 { Klass* intf = find_interface_field(name, sig, fd);
1926 if (intf != nullptr) return intf;
1927 }
1928 // 3) apply field lookup recursively if superclass exists
1929 { Klass* supr = super();
1930 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1931 }
1932 // 4) otherwise field lookup fails
1933 return nullptr;
1934 }
1935
1936
1937 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1938 // search order according to newest JVM spec (5.4.3.2, p.167).
1939 // 1) search for field in current klass
1940 if (find_local_field(name, sig, fd)) {
1941 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1942 }
1943 // 2) search for field recursively in direct superinterfaces
1944 if (is_static) {
1945 Klass* intf = find_interface_field(name, sig, fd);
1946 if (intf != nullptr) return intf;
1947 }
1948 // 3) apply field lookup recursively if superclass exists
1949 { Klass* supr = super();
1950 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1951 }
1952 // 4) otherwise field lookup fails
1953 return nullptr;
1954 }
1955
1956 bool InstanceKlass::contains_field_offset(int offset) {
1957 if (this->is_inline_klass()) {
1958 InlineKlass* vk = InlineKlass::cast(this);
1959 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->payload_size_in_bytes());
1960 } else {
1961 fieldDescriptor fd;
1962 return find_field_from_offset(offset, false, &fd);
1963 }
1964 }
1965
1966 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1967 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1968 if (fs.offset() == offset) {
1969 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1970 if (fd->is_static() == is_static) return true;
1971 }
1972 }
1973 return false;
1974 }
1975
1976
1977 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1978 Klass* klass = const_cast<InstanceKlass*>(this);
1979 while (klass != nullptr) {
1980 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1981 return true;
1982 }
1983 klass = klass->super();
1984 }
1985 return false;
1986 }
1987
1988
1989 void InstanceKlass::methods_do(void f(Method* method)) {
1990 // Methods aren't stable until they are loaded. This can be read outside
1991 // a lock through the ClassLoaderData for profiling
1992 // Redefined scratch classes are on the list and need to be cleaned
1993 if (!is_loaded() && !is_scratch_class()) {
1994 return;
1995 }
1996
1997 int len = methods()->length();
1998 for (int index = 0; index < len; index++) {
1999 Method* m = methods()->at(index);
2000 assert(m->is_method(), "must be method");
2001 f(m);
2002 }
2003 }
2004
2005
2006 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
2007 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2008 if (fs.access_flags().is_static()) {
2009 fieldDescriptor& fd = fs.field_descriptor();
2010 cl->do_field(&fd);
2011 }
2012 }
2013 }
2014
2015
2016 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
2017 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
2018 if (fs.access_flags().is_static()) {
2019 fieldDescriptor& fd = fs.field_descriptor();
2020 f(&fd, mirror, CHECK);
2021 }
2022 }
2023 }
2024
2025 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
2026 InstanceKlass* super = superklass();
2027 if (super != nullptr) {
2028 super->do_nonstatic_fields(cl);
2029 }
2030 fieldDescriptor fd;
2031 int length = java_fields_count();
2032 for (int i = 0; i < length; i += 1) {
2033 fd.reinitialize(this, i);
2034 if (!fd.is_static()) {
2035 cl->do_field(&fd);
2036 }
2037 }
2038 }
2039
2040 // first in Pair is offset, second is index.
2041 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
2042 return a->first - b->first;
2043 }
2044
2045 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
2046 InstanceKlass* super = superklass();
2047 if (super != nullptr) {
2048 super->print_nonstatic_fields(cl);
2049 }
2050 ResourceMark rm;
2051 fieldDescriptor fd;
2052 // In DebugInfo nonstatic fields are sorted by offset.
2053 GrowableArray<Pair<int,int> > fields_sorted;
2054 int i = 0;
2055 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2056 if (!fs.access_flags().is_static()) {
2057 fd = fs.field_descriptor();
2058 Pair<int,int> f(fs.offset(), fs.index());
2059 fields_sorted.push(f);
2060 i++;
2061 }
2062 }
2063 if (i > 0) {
2064 int length = i;
2065 assert(length == fields_sorted.length(), "duh");
2066 fields_sorted.sort(compare_fields_by_offset);
2067 for (int i = 0; i < length; i++) {
2068 fd.reinitialize(this, fields_sorted.at(i).second);
2069 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
2070 cl->do_field(&fd);
2071 }
2072 }
2073 }
2074
2075 #ifdef ASSERT
2076 static int linear_search(const Array<Method*>* methods,
2077 const Symbol* name,
2078 const Symbol* signature) {
2079 const int len = methods->length();
2080 for (int index = 0; index < len; index++) {
2081 const Method* const m = methods->at(index);
2082 assert(m->is_method(), "must be method");
2083 if (m->signature() == signature && m->name() == name) {
2084 return index;
2085 }
2086 }
2087 return -1;
2088 }
2089 #endif
2090
2091 bool InstanceKlass::_disable_method_binary_search = false;
2092
2093 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2094 int len = methods->length();
2095 int l = 0;
2096 int h = len - 1;
2097 while (l <= h) {
2098 Method* m = methods->at(l);
2099 if (m->name() == name) {
2100 return l;
2101 }
2102 l++;
2103 }
2104 return -1;
2105 }
2106
2107 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2108 if (_disable_method_binary_search) {
2109 assert(CDSConfig::is_dumping_dynamic_archive(), "must be");
2110 // At the final stage of dynamic dumping, the methods array may not be sorted
2111 // by ascending addresses of their names, so we can't use binary search anymore.
2112 // However, methods with the same name are still laid out consecutively inside the
2113 // methods array, so let's look for the first one that matches.
2114 return linear_search(methods, name);
2115 }
2116
2117 int len = methods->length();
2118 int l = 0;
2119 int h = len - 1;
2120
2121 // methods are sorted by ascending addresses of their names, so do binary search
2122 while (l <= h) {
2123 int mid = (l + h) >> 1;
2124 Method* m = methods->at(mid);
2125 assert(m->is_method(), "must be method");
2126 int res = m->name()->fast_compare(name);
2127 if (res == 0) {
2128 return mid;
2129 } else if (res < 0) {
2130 l = mid + 1;
2131 } else {
2132 h = mid - 1;
2133 }
2134 }
2135 return -1;
2136 }
2137
2138 // find_method looks up the name/signature in the local methods array
2139 Method* InstanceKlass::find_method(const Symbol* name,
2140 const Symbol* signature) const {
2141 return find_method_impl(name, signature,
2142 OverpassLookupMode::find,
2143 StaticLookupMode::find,
2144 PrivateLookupMode::find);
2145 }
2146
2147 Method* InstanceKlass::find_method_impl(const Symbol* name,
2148 const Symbol* signature,
2149 OverpassLookupMode overpass_mode,
2150 StaticLookupMode static_mode,
2151 PrivateLookupMode private_mode) const {
2152 return InstanceKlass::find_method_impl(methods(),
2153 name,
2154 signature,
2155 overpass_mode,
2156 static_mode,
2157 private_mode);
2158 }
2159
2160 // find_instance_method looks up the name/signature in the local methods array
2161 // and skips over static methods
2162 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2163 const Symbol* name,
2164 const Symbol* signature,
2165 PrivateLookupMode private_mode) {
2166 Method* const meth = InstanceKlass::find_method_impl(methods,
2167 name,
2168 signature,
2169 OverpassLookupMode::find,
2170 StaticLookupMode::skip,
2171 private_mode);
2172 assert(((meth == nullptr) || !meth->is_static()),
2173 "find_instance_method should have skipped statics");
2174 return meth;
2175 }
2176
2177 // find_instance_method looks up the name/signature in the local methods array
2178 // and skips over static methods
2179 Method* InstanceKlass::find_instance_method(const Symbol* name,
2180 const Symbol* signature,
2181 PrivateLookupMode private_mode) const {
2182 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2183 }
2184
2185 // Find looks up the name/signature in the local methods array
2186 // and filters on the overpass, static and private flags
2187 // This returns the first one found
2188 // note that the local methods array can have up to one overpass, one static
2189 // and one instance (private or not) with the same name/signature
2190 Method* InstanceKlass::find_local_method(const Symbol* name,
2191 const Symbol* signature,
2192 OverpassLookupMode overpass_mode,
2193 StaticLookupMode static_mode,
2194 PrivateLookupMode private_mode) const {
2195 return InstanceKlass::find_method_impl(methods(),
2196 name,
2197 signature,
2198 overpass_mode,
2199 static_mode,
2200 private_mode);
2201 }
2202
2203 // Find looks up the name/signature in the local methods array
2204 // and filters on the overpass, static and private flags
2205 // This returns the first one found
2206 // note that the local methods array can have up to one overpass, one static
2207 // and one instance (private or not) with the same name/signature
2208 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2209 const Symbol* name,
2210 const Symbol* signature,
2211 OverpassLookupMode overpass_mode,
2212 StaticLookupMode static_mode,
2213 PrivateLookupMode private_mode) {
2214 return InstanceKlass::find_method_impl(methods,
2215 name,
2216 signature,
2217 overpass_mode,
2218 static_mode,
2219 private_mode);
2220 }
2221
2222 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2223 const Symbol* name,
2224 const Symbol* signature) {
2225 return InstanceKlass::find_method_impl(methods,
2226 name,
2227 signature,
2228 OverpassLookupMode::find,
2229 StaticLookupMode::find,
2230 PrivateLookupMode::find);
2231 }
2232
2233 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2234 const Symbol* name,
2235 const Symbol* signature,
2236 OverpassLookupMode overpass_mode,
2237 StaticLookupMode static_mode,
2238 PrivateLookupMode private_mode) {
2239 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2240 return hit >= 0 ? methods->at(hit): nullptr;
2241 }
2242
2243 // true if method matches signature and conforms to skipping_X conditions.
2244 static bool method_matches(const Method* m,
2245 const Symbol* signature,
2246 bool skipping_overpass,
2247 bool skipping_static,
2248 bool skipping_private) {
2249 return ((m->signature() == signature) &&
2250 (!skipping_overpass || !m->is_overpass()) &&
2251 (!skipping_static || !m->is_static()) &&
2252 (!skipping_private || !m->is_private()));
2253 }
2254
2255 // Used directly for default_methods to find the index into the
2256 // default_vtable_indices, and indirectly by find_method
2257 // find_method_index looks in the local methods array to return the index
2258 // of the matching name/signature. If, overpass methods are being ignored,
2259 // the search continues to find a potential non-overpass match. This capability
2260 // is important during method resolution to prefer a static method, for example,
2261 // over an overpass method.
2262 // There is the possibility in any _method's array to have the same name/signature
2263 // for a static method, an overpass method and a local instance method
2264 // To correctly catch a given method, the search criteria may need
2265 // to explicitly skip the other two. For local instance methods, it
2266 // is often necessary to skip private methods
2267 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2268 const Symbol* name,
2269 const Symbol* signature,
2270 OverpassLookupMode overpass_mode,
2271 StaticLookupMode static_mode,
2272 PrivateLookupMode private_mode) {
2273 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2274 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2275 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2276 const int hit = quick_search(methods, name);
2277 if (hit != -1) {
2278 const Method* const m = methods->at(hit);
2279
2280 // Do linear search to find matching signature. First, quick check
2281 // for common case, ignoring overpasses if requested.
2282 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2283 return hit;
2284 }
2285
2286 // search downwards through overloaded methods
2287 int i;
2288 for (i = hit - 1; i >= 0; --i) {
2289 const Method* const m = methods->at(i);
2290 assert(m->is_method(), "must be method");
2291 if (m->name() != name) {
2292 break;
2293 }
2294 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2295 return i;
2296 }
2297 }
2298 // search upwards
2299 for (i = hit + 1; i < methods->length(); ++i) {
2300 const Method* const m = methods->at(i);
2301 assert(m->is_method(), "must be method");
2302 if (m->name() != name) {
2303 break;
2304 }
2305 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2306 return i;
2307 }
2308 }
2309 // not found
2310 #ifdef ASSERT
2311 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2312 linear_search(methods, name, signature);
2313 assert(-1 == index, "binary search should have found entry %d", index);
2314 #endif
2315 }
2316 return -1;
2317 }
2318
2319 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2320 return find_method_by_name(methods(), name, end);
2321 }
2322
2323 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2324 const Symbol* name,
2325 int* end_ptr) {
2326 assert(end_ptr != nullptr, "just checking");
2327 int start = quick_search(methods, name);
2328 int end = start + 1;
2329 if (start != -1) {
2330 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2331 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2332 *end_ptr = end;
2333 return start;
2334 }
2335 return -1;
2336 }
2337
2338 // uncached_lookup_method searches both the local class methods array and all
2339 // superclasses methods arrays, skipping any overpass methods in superclasses,
2340 // and possibly skipping private methods.
2341 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2342 const Symbol* signature,
2343 OverpassLookupMode overpass_mode,
2344 PrivateLookupMode private_mode) const {
2345 OverpassLookupMode overpass_local_mode = overpass_mode;
2346 const Klass* klass = this;
2347 while (klass != nullptr) {
2348 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2349 signature,
2350 overpass_local_mode,
2351 StaticLookupMode::find,
2352 private_mode);
2353 if (method != nullptr) {
2354 return method;
2355 }
2356 if (name == vmSymbols::object_initializer_name()) {
2357 break; // <init> is never inherited
2358 }
2359 klass = klass->super();
2360 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2361 }
2362 return nullptr;
2363 }
2364
2365 #ifdef ASSERT
2366 // search through class hierarchy and return true if this class or
2367 // one of the superclasses was redefined
2368 bool InstanceKlass::has_redefined_this_or_super() const {
2369 const Klass* klass = this;
2370 while (klass != nullptr) {
2371 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2372 return true;
2373 }
2374 klass = klass->super();
2375 }
2376 return false;
2377 }
2378 #endif
2379
2380 // lookup a method in the default methods list then in all transitive interfaces
2381 // Do NOT return private or static methods
2382 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2383 Symbol* signature) const {
2384 Method* m = nullptr;
2385 if (default_methods() != nullptr) {
2386 m = find_method(default_methods(), name, signature);
2387 }
2388 // Look up interfaces
2389 if (m == nullptr) {
2390 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2391 }
2392 return m;
2393 }
2394
2395 // lookup a method in all the interfaces that this class implements
2396 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2397 // They should only be found in the initial InterfaceMethodRef
2398 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2399 Symbol* signature,
2400 DefaultsLookupMode defaults_mode) const {
2401 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2402 int num_ifs = all_ifs->length();
2403 InstanceKlass *ik = nullptr;
2404 for (int i = 0; i < num_ifs; i++) {
2405 ik = all_ifs->at(i);
2406 Method* m = ik->lookup_method(name, signature);
2407 if (m != nullptr && m->is_public() && !m->is_static() &&
2408 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2409 return m;
2410 }
2411 }
2412 return nullptr;
2413 }
2414
2415 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2416 :_st(st), _verbose(verbose) {
2417 ResourceMark rm;
2418 _st->print("%-18s ", "KlassAddr");
2419 _st->print("%-4s ", "Size");
2420 _st->print("%-20s ", "State");
2421 _st->print("%-7s ", "Flags");
2422 _st->print("%-5s ", "ClassName");
2423 _st->cr();
2424 }
2425
2426 void PrintClassClosure::do_klass(Klass* k) {
2427 ResourceMark rm;
2428 // klass pointer
2429 _st->print(PTR_FORMAT " ", p2i(k));
2430 // klass size
2431 _st->print("%4d ", k->size());
2432 // initialization state
2433 if (k->is_instance_klass()) {
2434 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2435 } else {
2436 _st->print("%-20s ","");
2437 }
2438 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2439 char buf[10];
2440 int i = 0;
2441 if (k->has_finalizer()) buf[i++] = 'F';
2442 if (k->is_instance_klass()) {
2443 InstanceKlass* ik = InstanceKlass::cast(k);
2444 if (ik->has_final_method()) buf[i++] = 'f';
2445 if (ik->is_rewritten()) buf[i++] = 'W';
2446 if (ik->is_contended()) buf[i++] = 'C';
2447 if (ik->has_been_redefined()) buf[i++] = 'R';
2448 if (ik->is_shared()) buf[i++] = 'S';
2449 }
2450 buf[i++] = '\0';
2451 _st->print("%-7s ", buf);
2452 // klass name
2453 _st->print("%-5s ", k->external_name());
2454 // end
2455 _st->cr();
2456 if (_verbose) {
2457 k->print_on(_st);
2458 }
2459 }
2460
2461 /* jni_id_for for jfieldIds only */
2462 JNIid* InstanceKlass::jni_id_for(int offset) {
2463 MutexLocker ml(JfieldIdCreation_lock);
2464 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2465 if (probe == nullptr) {
2466 // Allocate new static field identifier
2467 probe = new JNIid(this, offset, jni_ids());
2468 set_jni_ids(probe);
2469 }
2470 return probe;
2471 }
2472
2473 u2 InstanceKlass::enclosing_method_data(int offset) const {
2474 const Array<jushort>* const inner_class_list = inner_classes();
2475 if (inner_class_list == nullptr) {
2476 return 0;
2477 }
2478 const int length = inner_class_list->length();
2479 if (length % inner_class_next_offset == 0) {
2480 return 0;
2481 }
2482 const int index = length - enclosing_method_attribute_size;
2483 assert(offset < enclosing_method_attribute_size, "invalid offset");
2484 return inner_class_list->at(index + offset);
2485 }
2486
2487 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2488 u2 method_index) {
2489 Array<jushort>* inner_class_list = inner_classes();
2490 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2491 int length = inner_class_list->length();
2492 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2493 int index = length - enclosing_method_attribute_size;
2494 inner_class_list->at_put(
2495 index + enclosing_method_class_index_offset, class_index);
2496 inner_class_list->at_put(
2497 index + enclosing_method_method_index_offset, method_index);
2498 }
2499 }
2500
2501 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) {
2502 if (method->is_old() && !method->is_obsolete()) {
2503 // If the method passed in is old (but not obsolete), use the current version.
2504 method = method_with_idnum((int)idnum);
2505 assert(method != nullptr, "old and but not obsolete, so should exist");
2506 }
2507 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method);
2508 Atomic::release_store(&jmeths[idnum + 1], new_id);
2509 return new_id;
2510 }
2511
2512 // Lookup or create a jmethodID.
2513 // This code is called by the VMThread and JavaThreads so the
2514 // locking has to be done very carefully to avoid deadlocks
2515 // and/or other cache consistency problems.
2516 //
2517 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2518 Method* method = method_h();
2519 int idnum = method->method_idnum();
2520 jmethodID* jmeths = methods_jmethod_ids_acquire();
2521
2522 // We use a double-check locking idiom here because this cache is
2523 // performance sensitive. In the normal system, this cache only
2524 // transitions from null to non-null which is safe because we use
2525 // release_set_methods_jmethod_ids() to advertise the new cache.
2526 // A partially constructed cache should never be seen by a racing
2527 // thread. We also use release_store() to save a new jmethodID
2528 // in the cache so a partially constructed jmethodID should never be
2529 // seen either. Cache reads of existing jmethodIDs proceed without a
2530 // lock, but cache writes of a new jmethodID requires uniqueness and
2531 // creation of the cache itself requires no leaks so a lock is
2532 // acquired in those two cases.
2533 //
2534 // If the RedefineClasses() API has been used, then this cache grows
2535 // in the redefinition safepoint.
2536
2537 if (jmeths == nullptr) {
2538 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2539 jmeths = methods_jmethod_ids_acquire();
2540 // Still null?
2541 if (jmeths == nullptr) {
2542 size_t size = idnum_allocated_count();
2543 assert(size > (size_t)idnum, "should already have space");
2544 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2545 memset(jmeths, 0, (size + 1) * sizeof(jmethodID));
2546 // cache size is stored in element[0], other elements offset by one
2547 jmeths[0] = (jmethodID)size;
2548 jmethodID new_id = update_jmethod_id(jmeths, method, idnum);
2549
2550 // publish jmeths
2551 release_set_methods_jmethod_ids(jmeths);
2552 return new_id;
2553 }
2554 }
2555
2556 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]);
2557 if (id == nullptr) {
2558 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2559 id = jmeths[idnum + 1];
2560 // Still null?
2561 if (id == nullptr) {
2562 return update_jmethod_id(jmeths, method, idnum);
2563 }
2564 }
2565 return id;
2566 }
2567
2568 void InstanceKlass::update_methods_jmethod_cache() {
2569 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2570 jmethodID* cache = _methods_jmethod_ids;
2571 if (cache != nullptr) {
2572 size_t size = idnum_allocated_count();
2573 size_t old_size = (size_t)cache[0];
2574 if (old_size < size + 1) {
2575 // Allocate a larger one and copy entries to the new one.
2576 // They've already been updated to point to new methods where applicable (i.e., not obsolete).
2577 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass);
2578 memset(new_cache, 0, (size + 1) * sizeof(jmethodID));
2579 // The cache size is stored in element[0]; the other elements are offset by one.
2580 new_cache[0] = (jmethodID)size;
2581
2582 for (int i = 1; i <= (int)old_size; i++) {
2583 new_cache[i] = cache[i];
2584 }
2585 _methods_jmethod_ids = new_cache;
2586 FREE_C_HEAP_ARRAY(jmethodID, cache);
2587 }
2588 }
2589 }
2590
2591 // Figure out how many jmethodIDs haven't been allocated, and make
2592 // sure space for them is pre-allocated. This makes getting all
2593 // method ids much, much faster with classes with more than 8
2594 // methods, and has a *substantial* effect on performance with jvmti
2595 // code that loads all jmethodIDs for all classes.
2596 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2597 int new_jmeths = 0;
2598 int length = methods()->length();
2599 for (int index = start_offset; index < length; index++) {
2600 Method* m = methods()->at(index);
2601 jmethodID id = m->find_jmethod_id_or_null();
2602 if (id == nullptr) {
2603 new_jmeths++;
2604 }
2605 }
2606 if (new_jmeths != 0) {
2607 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2608 }
2609 }
2610
2611 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2612 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2613 int idnum = method->method_idnum();
2614 jmethodID* jmeths = methods_jmethod_ids_acquire();
2615 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr;
2616 }
2617
2618 inline DependencyContext InstanceKlass::dependencies() {
2619 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2620 return dep_context;
2621 }
2622
2623 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2624 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2625 }
2626
2627 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2628 dependencies().add_dependent_nmethod(nm);
2629 }
2630
2631 void InstanceKlass::clean_dependency_context() {
2632 dependencies().clean_unloading_dependents();
2633 }
2634
2635 #ifndef PRODUCT
2636 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2637 dependencies().print_dependent_nmethods(verbose);
2638 }
2639
2640 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2641 return dependencies().is_dependent_nmethod(nm);
2642 }
2643 #endif //PRODUCT
2644
2645 void InstanceKlass::clean_weak_instanceklass_links() {
2646 clean_implementors_list();
2647 clean_method_data();
2648 }
2649
2650 void InstanceKlass::clean_implementors_list() {
2651 assert(is_loader_alive(), "this klass should be live");
2652 if (is_interface()) {
2653 assert (ClassUnloading, "only called for ClassUnloading");
2654 for (;;) {
2655 // Use load_acquire due to competing with inserts
2656 InstanceKlass* volatile* iklass = adr_implementor();
2657 assert(iklass != nullptr, "Klass must not be null");
2658 InstanceKlass* impl = Atomic::load_acquire(iklass);
2659 if (impl != nullptr && !impl->is_loader_alive()) {
2660 // null this field, might be an unloaded instance klass or null
2661 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2662 // Successfully unlinking implementor.
2663 if (log_is_enabled(Trace, class, unload)) {
2664 ResourceMark rm;
2665 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2666 }
2667 return;
2668 }
2669 } else {
2670 return;
2671 }
2672 }
2673 }
2674 }
2675
2676 void InstanceKlass::clean_method_data() {
2677 for (int m = 0; m < methods()->length(); m++) {
2678 MethodData* mdo = methods()->at(m)->method_data();
2679 if (mdo != nullptr) {
2680 mdo->clean_method_data(/*always_clean*/false);
2681 }
2682 }
2683 }
2684
2685 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2686 Klass::metaspace_pointers_do(it);
2687
2688 if (log_is_enabled(Trace, cds)) {
2689 ResourceMark rm;
2690 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2691 }
2692
2693 it->push(&_annotations);
2694 it->push((Klass**)&_array_klasses);
2695 if (!is_rewritten()) {
2696 it->push(&_constants, MetaspaceClosure::_writable);
2697 } else {
2698 it->push(&_constants);
2699 }
2700 it->push(&_inner_classes);
2701 #if INCLUDE_JVMTI
2702 it->push(&_previous_versions);
2703 #endif
2704 #if INCLUDE_CDS
2705 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2706 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2707 // be writable. The length check on the _methods is necessary because classes which
2708 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2709 if (_methods != nullptr && _methods->length() > 0 &&
2710 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2711 // To handle jsr bytecode, new Method* maybe stored into _methods
2712 it->push(&_methods, MetaspaceClosure::_writable);
2713 } else {
2714 #endif
2715 it->push(&_methods);
2716 #if INCLUDE_CDS
2717 }
2718 #endif
2719 it->push(&_default_methods);
2720 it->push(&_local_interfaces);
2721 it->push(&_transitive_interfaces);
2722 it->push(&_method_ordering);
2723 if (!is_rewritten()) {
2724 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2725 } else {
2726 it->push(&_default_vtable_indices);
2727 }
2728
2729 it->push(&_fieldinfo_stream);
2730 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2731 it->push(&_fields_status, MetaspaceClosure::_writable);
2732
2733 if (itable_length() > 0) {
2734 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2735 int method_table_offset_in_words = ioe->offset()/wordSize;
2736 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2737
2738 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2739 / itableOffsetEntry::size();
2740
2741 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2742 if (ioe->interface_klass() != nullptr) {
2743 it->push(ioe->interface_klass_addr());
2744 itableMethodEntry* ime = ioe->first_method_entry(this);
2745 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2746 for (int index = 0; index < n; index ++) {
2747 it->push(ime[index].method_addr());
2748 }
2749 }
2750 }
2751 }
2752
2753 it->push(&_nest_members);
2754 it->push(&_permitted_subclasses);
2755 it->push(&_loadable_descriptors);
2756 it->push(&_record_components);
2757 it->push(&_inline_layout_info_array, MetaspaceClosure::_writable);
2758 }
2759
2760 #if INCLUDE_CDS
2761 void InstanceKlass::remove_unshareable_info() {
2762
2763 if (is_linked()) {
2764 assert(can_be_verified_at_dumptime(), "must be");
2765 // Remember this so we can avoid walking the hierarchy at runtime.
2766 set_verified_at_dump_time();
2767 }
2768
2769 Klass::remove_unshareable_info();
2770
2771 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2772 // Classes are attempted to link during dumping and may fail,
2773 // but these classes are still in the dictionary and class list in CLD.
2774 // If the class has failed verification, there is nothing else to remove.
2775 return;
2776 }
2777
2778 // Reset to the 'allocated' state to prevent any premature accessing to
2779 // a shared class at runtime while the class is still being loaded and
2780 // restored. A class' init_state is set to 'loaded' at runtime when it's
2781 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2782 _init_state = allocated;
2783
2784 { // Otherwise this needs to take out the Compile_lock.
2785 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2786 init_implementor();
2787 }
2788
2789 // Call remove_unshareable_info() on other objects that belong to this class, except
2790 // for constants()->remove_unshareable_info(), which is called in a separate pass in
2791 // ArchiveBuilder::make_klasses_shareable(),
2792
2793 for (int i = 0; i < methods()->length(); i++) {
2794 Method* m = methods()->at(i);
2795 m->remove_unshareable_info();
2796 }
2797
2798 // do array classes also.
2799 if (array_klasses() != nullptr) {
2800 array_klasses()->remove_unshareable_info();
2801 }
2802
2803 // These are not allocated from metaspace. They are safe to set to nullptr.
2804 _source_debug_extension = nullptr;
2805 _dep_context = nullptr;
2806 _osr_nmethods_head = nullptr;
2807 #if INCLUDE_JVMTI
2808 _breakpoints = nullptr;
2809 _previous_versions = nullptr;
2810 _cached_class_file = nullptr;
2811 _jvmti_cached_class_field_map = nullptr;
2812 #endif
2813
2814 _init_thread = nullptr;
2815 _methods_jmethod_ids = nullptr;
2816 _jni_ids = nullptr;
2817 _oop_map_cache = nullptr;
2818 // clear _nest_host to ensure re-load at runtime
2819 _nest_host = nullptr;
2820 init_shared_package_entry();
2821 _dep_context_last_cleaned = 0;
2822
2823 remove_unshareable_flags();
2824 }
2825
2826 void InstanceKlass::remove_unshareable_flags() {
2827 // clear all the flags/stats that shouldn't be in the archived version
2828 assert(!is_scratch_class(), "must be");
2829 assert(!has_been_redefined(), "must be");
2830 #if INCLUDE_JVMTI
2831 set_is_being_redefined(false);
2832 #endif
2833 set_has_resolved_methods(false);
2834 }
2835
2836 void InstanceKlass::remove_java_mirror() {
2837 Klass::remove_java_mirror();
2838
2839 // do array classes also.
2840 if (array_klasses() != nullptr) {
2841 array_klasses()->remove_java_mirror();
2842 }
2843 }
2844
2845 void InstanceKlass::init_shared_package_entry() {
2846 assert(CDSConfig::is_dumping_archive(), "must be");
2847 #if !INCLUDE_CDS_JAVA_HEAP
2848 _package_entry = nullptr;
2849 #else
2850 if (CDSConfig::is_dumping_full_module_graph()) {
2851 if (is_shared_unregistered_class()) {
2852 _package_entry = nullptr;
2853 } else {
2854 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2855 }
2856 } else if (CDSConfig::is_dumping_dynamic_archive() &&
2857 CDSConfig::is_using_full_module_graph() &&
2858 MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2859 // _package_entry is an archived package in the base archive. Leave it as is.
2860 } else {
2861 _package_entry = nullptr;
2862 }
2863 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2864 #endif
2865 }
2866
2867 void InstanceKlass::compute_has_loops_flag_for_methods() {
2868 Array<Method*>* methods = this->methods();
2869 for (int index = 0; index < methods->length(); ++index) {
2870 Method* m = methods->at(index);
2871 if (!m->is_overpass()) { // work around JDK-8305771
2872 m->compute_has_loops_flag();
2873 }
2874 }
2875 }
2876
2877 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2878 PackageEntry* pkg_entry, TRAPS) {
2879 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2880 // before the InstanceKlass is added to the SystemDictionary. Make
2881 // sure the current state is <loaded.
2882 assert(!is_loaded(), "invalid init state");
2883 assert(!shared_loading_failed(), "Must not try to load failed class again");
2884 set_package(loader_data, pkg_entry, CHECK);
2885 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2886
2887 if (is_inline_klass()) {
2888 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2889 }
2890
2891 Array<Method*>* methods = this->methods();
2892 int num_methods = methods->length();
2893 for (int index = 0; index < num_methods; ++index) {
2894 methods->at(index)->restore_unshareable_info(CHECK);
2895 }
2896 #if INCLUDE_JVMTI
2897 if (JvmtiExport::has_redefined_a_class()) {
2898 // Reinitialize vtable because RedefineClasses may have changed some
2899 // entries in this vtable for super classes so the CDS vtable might
2900 // point to old or obsolete entries. RedefineClasses doesn't fix up
2901 // vtables in the shared system dictionary, only the main one.
2902 // It also redefines the itable too so fix that too.
2903 // First fix any default methods that point to a super class that may
2904 // have been redefined.
2905 bool trace_name_printed = false;
2906 adjust_default_methods(&trace_name_printed);
2907 vtable().initialize_vtable();
2908 itable().initialize_itable();
2909 }
2910 #endif
2911
2912 // restore constant pool resolved references
2913 constants()->restore_unshareable_info(CHECK);
2914
2915 if (array_klasses() != nullptr) {
2916 // To get a consistent list of classes we need MultiArray_lock to ensure
2917 // array classes aren't observed while they are being restored.
2918 RecursiveLocker rl(MultiArray_lock, THREAD);
2919 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity");
2920 // Array classes have null protection domain.
2921 // --> see ArrayKlass::complete_create_array_klass()
2922 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK);
2923 }
2924
2925 // Initialize @ValueBased class annotation if not already set in the archived klass.
2926 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) {
2927 set_is_value_based();
2928 }
2929 }
2930
2931 // Check if a class or any of its supertypes has a version older than 50.
2932 // CDS will not perform verification of old classes during dump time because
2933 // without changing the old verifier, the verification constraint cannot be
2934 // retrieved during dump time.
2935 // Verification of archived old classes will be performed during run time.
2936 bool InstanceKlass::can_be_verified_at_dumptime() const {
2937 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2938 // This is a class that was dumped into the base archive, so we know
2939 // it was verified at dump time.
2940 return true;
2941 }
2942 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2943 return false;
2944 }
2945 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2946 return false;
2947 }
2948 Array<InstanceKlass*>* interfaces = local_interfaces();
2949 int len = interfaces->length();
2950 for (int i = 0; i < len; i++) {
2951 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2952 return false;
2953 }
2954 }
2955 return true;
2956 }
2957
2958 bool InstanceKlass::methods_contain_jsr_bytecode() const {
2959 Thread* thread = Thread::current();
2960 for (int i = 0; i < _methods->length(); i++) {
2961 methodHandle m(thread, _methods->at(i));
2962 BytecodeStream bcs(m);
2963 while (!bcs.is_last_bytecode()) {
2964 Bytecodes::Code opcode = bcs.next();
2965 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
2966 return true;
2967 }
2968 }
2969 }
2970 return false;
2971 }
2972 #endif // INCLUDE_CDS
2973
2974 #if INCLUDE_JVMTI
2975 static void clear_all_breakpoints(Method* m) {
2976 m->clear_all_breakpoints();
2977 }
2978 #endif
2979
2980 void InstanceKlass::unload_class(InstanceKlass* ik) {
2981
2982 if (ik->is_scratch_class()) {
2983 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes");
2984 return;
2985 }
2986 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik));
2987
2988 // Release dependencies.
2989 ik->dependencies().remove_all_dependents();
2990
2991 // notify the debugger
2992 if (JvmtiExport::should_post_class_unload()) {
2993 JvmtiExport::post_class_unload(ik);
2994 }
2995
2996 // notify ClassLoadingService of class unload
2997 ClassLoadingService::notify_class_unloaded(ik);
2998
2999 SystemDictionaryShared::handle_class_unloading(ik);
3000
3001 if (log_is_enabled(Info, class, unload)) {
3002 ResourceMark rm;
3003 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3004 }
3005
3006 Events::log_class_unloading(Thread::current(), ik);
3007
3008 #if INCLUDE_JFR
3009 assert(ik != nullptr, "invariant");
3010 EventClassUnload event;
3011 event.set_unloadedClass(ik);
3012 event.set_definingClassLoader(ik->class_loader_data());
3013 event.commit();
3014 #endif
3015 }
3016
3017 static void method_release_C_heap_structures(Method* m) {
3018 m->release_C_heap_structures();
3019 }
3020
3021 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3022 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3023 // Clean up C heap
3024 Klass::release_C_heap_structures();
3025
3026 // Deallocate and call destructors for MDO mutexes
3027 if (release_sub_metadata) {
3028 methods_do(method_release_C_heap_structures);
3029 }
3030
3031 // Deallocate oop map cache
3032 if (_oop_map_cache != nullptr) {
3033 delete _oop_map_cache;
3034 _oop_map_cache = nullptr;
3035 }
3036
3037 // Deallocate JNI identifiers for jfieldIDs
3038 JNIid::deallocate(jni_ids());
3039 set_jni_ids(nullptr);
3040
3041 jmethodID* jmeths = methods_jmethod_ids_acquire();
3042 if (jmeths != nullptr) {
3043 release_set_methods_jmethod_ids(nullptr);
3044 FreeHeap(jmeths);
3045 }
3046
3047 assert(_dep_context == nullptr,
3048 "dependencies should already be cleaned");
3049
3050 #if INCLUDE_JVMTI
3051 // Deallocate breakpoint records
3052 if (breakpoints() != nullptr) {
3053 methods_do(clear_all_breakpoints);
3054 assert(breakpoints() == nullptr, "should have cleared breakpoints");
3055 }
3056
3057 // deallocate the cached class file
3058 if (_cached_class_file != nullptr) {
3059 os::free(_cached_class_file);
3060 _cached_class_file = nullptr;
3061 }
3062 #endif
3063
3064 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3065
3066 if (release_sub_metadata) {
3067 constants()->release_C_heap_structures();
3068 }
3069 }
3070
3071 // The constant pool is on stack if any of the methods are executing or
3072 // referenced by handles.
3073 bool InstanceKlass::on_stack() const {
3074 return _constants->on_stack();
3075 }
3076
3077 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3078 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3079 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3080
3081 // minor and major version numbers of class file
3082 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3083 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3084 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3085 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3086
3087 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3088 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3089 if (ik->constants()->version() == version) {
3090 return ik;
3091 }
3092 }
3093 return nullptr;
3094 }
3095
3096 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3097 if (array == nullptr) {
3098 _source_debug_extension = nullptr;
3099 } else {
3100 // Adding one to the attribute length in order to store a null terminator
3101 // character could cause an overflow because the attribute length is
3102 // already coded with an u4 in the classfile, but in practice, it's
3103 // unlikely to happen.
3104 assert((length+1) > length, "Overflow checking");
3105 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3106 for (int i = 0; i < length; i++) {
3107 sde[i] = array[i];
3108 }
3109 sde[length] = '\0';
3110 _source_debug_extension = sde;
3111 }
3112 }
3113
3114 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3115 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3116 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3117
3118 const char* InstanceKlass::signature_name() const {
3119 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3120 }
3121
3122 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3123 // Get the internal name as a c string
3124 const char* src = (const char*) (name()->as_C_string());
3125 const int src_length = (int)strlen(src);
3126
3127 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3128
3129 // Add L or Q as type indicator
3130 int dest_index = 0;
3131 dest[dest_index++] = c;
3132
3133 // Add the actual class name
3134 for (int src_index = 0; src_index < src_length; ) {
3135 dest[dest_index++] = src[src_index++];
3136 }
3137
3138 if (is_hidden()) { // Replace the last '+' with a '.'.
3139 for (int index = (int)src_length; index > 0; index--) {
3140 if (dest[index] == '+') {
3141 dest[index] = JVM_SIGNATURE_DOT;
3142 break;
3143 }
3144 }
3145 }
3146
3147 // Add the semicolon and the null
3148 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3149 dest[dest_index] = '\0';
3150 return dest;
3151 }
3152
3153 ModuleEntry* InstanceKlass::module() const {
3154 if (is_hidden() &&
3155 in_unnamed_package() &&
3156 class_loader_data()->has_class_mirror_holder()) {
3157 // For a non-strong hidden class defined to an unnamed package,
3158 // its (class held) CLD will not have an unnamed module created for it.
3159 // Two choices to find the correct ModuleEntry:
3160 // 1. If hidden class is within a nest, use nest host's module
3161 // 2. Find the unnamed module off from the class loader
3162 // For now option #2 is used since a nest host is not set until
3163 // after the instance class is created in jvm_lookup_define_class().
3164 if (class_loader_data()->is_boot_class_loader_data()) {
3165 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3166 } else {
3167 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3168 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3169 return java_lang_Module::module_entry(module);
3170 }
3171 }
3172
3173 // Class is in a named package
3174 if (!in_unnamed_package()) {
3175 return _package_entry->module();
3176 }
3177
3178 // Class is in an unnamed package, return its loader's unnamed module
3179 return class_loader_data()->unnamed_module();
3180 }
3181
3182 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3183
3184 // ensure java/ packages only loaded by boot or platform builtin loaders
3185 // not needed for shared class since CDS does not archive prohibited classes.
3186 if (!is_shared()) {
3187 check_prohibited_package(name(), loader_data, CHECK);
3188 }
3189
3190 if (is_shared() && _package_entry != nullptr) {
3191 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) {
3192 // we can use the saved package
3193 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3194 return;
3195 } else {
3196 _package_entry = nullptr;
3197 }
3198 }
3199
3200 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3201 // it returns, so we need to decrement it when the current function exits.
3202 TempNewSymbol from_class_name =
3203 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3204
3205 Symbol* pkg_name;
3206 if (pkg_entry != nullptr) {
3207 pkg_name = pkg_entry->name();
3208 } else {
3209 pkg_name = from_class_name;
3210 }
3211
3212 if (pkg_name != nullptr && loader_data != nullptr) {
3213
3214 // Find in class loader's package entry table.
3215 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3216
3217 // If the package name is not found in the loader's package
3218 // entry table, it is an indication that the package has not
3219 // been defined. Consider it defined within the unnamed module.
3220 if (_package_entry == nullptr) {
3221
3222 if (!ModuleEntryTable::javabase_defined()) {
3223 // Before java.base is defined during bootstrapping, define all packages in
3224 // the java.base module. If a non-java.base package is erroneously placed
3225 // in the java.base module it will be caught later when java.base
3226 // is defined by ModuleEntryTable::verify_javabase_packages check.
3227 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3228 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3229 } else {
3230 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3231 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3232 }
3233
3234 // A package should have been successfully created
3235 DEBUG_ONLY(ResourceMark rm(THREAD));
3236 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3237 name()->as_C_string(), loader_data->loader_name_and_id());
3238 }
3239
3240 if (log_is_enabled(Debug, module)) {
3241 ResourceMark rm(THREAD);
3242 ModuleEntry* m = _package_entry->module();
3243 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3244 external_name(),
3245 pkg_name->as_C_string(),
3246 loader_data->loader_name_and_id(),
3247 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3248 }
3249 } else {
3250 ResourceMark rm(THREAD);
3251 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3252 external_name(),
3253 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3254 UNNAMED_MODULE);
3255 }
3256 }
3257
3258 // Function set_classpath_index ensures that for a non-null _package_entry
3259 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3260 // It then sets the classpath_index in the package entry record.
3261 //
3262 // The classpath_index field is used to find the entry on the boot loader class
3263 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3264 // in an unnamed module. It is also used to indicate (for all packages whose
3265 // classes are loaded by the boot loader) that at least one of the package's
3266 // classes has been loaded.
3267 void InstanceKlass::set_classpath_index(s2 path_index) {
3268 if (_package_entry != nullptr) {
3269 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3270 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3271 assert(path_index != -1, "Unexpected classpath_index");
3272 _package_entry->set_classpath_index(path_index);
3273 }
3274 }
3275
3276 // different versions of is_same_class_package
3277
3278 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3279 oop classloader1 = this->class_loader();
3280 PackageEntry* classpkg1 = this->package();
3281 if (class2->is_objArray_klass()) {
3282 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3283 }
3284
3285 oop classloader2;
3286 PackageEntry* classpkg2;
3287 if (class2->is_instance_klass()) {
3288 classloader2 = class2->class_loader();
3289 classpkg2 = class2->package();
3290 } else {
3291 assert(class2->is_typeArray_klass(), "should be type array");
3292 classloader2 = nullptr;
3293 classpkg2 = nullptr;
3294 }
3295
3296 // Same package is determined by comparing class loader
3297 // and package entries. Both must be the same. This rule
3298 // applies even to classes that are defined in the unnamed
3299 // package, they still must have the same class loader.
3300 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3301 return true;
3302 }
3303
3304 return false;
3305 }
3306
3307 // return true if this class and other_class are in the same package. Classloader
3308 // and classname information is enough to determine a class's package
3309 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3310 const Symbol* other_class_name) const {
3311 if (class_loader() != other_class_loader) {
3312 return false;
3313 }
3314 if (name()->fast_compare(other_class_name) == 0) {
3315 return true;
3316 }
3317
3318 {
3319 ResourceMark rm;
3320
3321 bool bad_class_name = false;
3322 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3323 if (bad_class_name) {
3324 return false;
3325 }
3326 // Check that package_from_class_name() returns null, not "", if there is no package.
3327 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3328
3329 const Symbol* const this_package_name =
3330 this->package() != nullptr ? this->package()->name() : nullptr;
3331
3332 if (this_package_name == nullptr || other_pkg == nullptr) {
3333 // One of the two doesn't have a package. Only return true if the other
3334 // one also doesn't have a package.
3335 return this_package_name == other_pkg;
3336 }
3337
3338 // Check if package is identical
3339 return this_package_name->fast_compare(other_pkg) == 0;
3340 }
3341 }
3342
3343 static bool is_prohibited_package_slow(Symbol* class_name) {
3344 // Caller has ResourceMark
3345 int length;
3346 jchar* unicode = class_name->as_unicode(length);
3347 return (length >= 5 &&
3348 unicode[0] == 'j' &&
3349 unicode[1] == 'a' &&
3350 unicode[2] == 'v' &&
3351 unicode[3] == 'a' &&
3352 unicode[4] == '/');
3353 }
3354
3355 // Only boot and platform class loaders can define classes in "java/" packages.
3356 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3357 ClassLoaderData* loader_data,
3358 TRAPS) {
3359 if (!loader_data->is_boot_class_loader_data() &&
3360 !loader_data->is_platform_class_loader_data() &&
3361 class_name != nullptr && class_name->utf8_length() >= 5) {
3362 ResourceMark rm(THREAD);
3363 bool prohibited;
3364 const u1* base = class_name->base();
3365 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3366 prohibited = is_prohibited_package_slow(class_name);
3367 } else {
3368 char* name = class_name->as_C_string();
3369 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3370 }
3371 if (prohibited) {
3372 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3373 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3374 char* name = pkg_name->as_C_string();
3375 const char* class_loader_name = loader_data->loader_name_and_id();
3376 StringUtils::replace_no_expand(name, "/", ".");
3377 const char* msg_text1 = "Class loader (instance of): ";
3378 const char* msg_text2 = " tried to load prohibited package name: ";
3379 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3380 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3381 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3382 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3383 }
3384 }
3385 return;
3386 }
3387
3388 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3389 constantPoolHandle i_cp(THREAD, constants());
3390 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3391 int ioff = iter.inner_class_info_index();
3392 if (ioff != 0) {
3393 // Check to see if the name matches the class we're looking for
3394 // before attempting to find the class.
3395 if (i_cp->klass_name_at_matches(this, ioff)) {
3396 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3397 if (this == inner_klass) {
3398 *ooff = iter.outer_class_info_index();
3399 *noff = iter.inner_name_index();
3400 return true;
3401 }
3402 }
3403 }
3404 }
3405 return false;
3406 }
3407
3408 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3409 InstanceKlass* outer_klass = nullptr;
3410 *inner_is_member = false;
3411 int ooff = 0, noff = 0;
3412 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3413 if (has_inner_classes_attr) {
3414 constantPoolHandle i_cp(THREAD, constants());
3415 if (ooff != 0) {
3416 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3417 if (!ok->is_instance_klass()) {
3418 // If the outer class is not an instance klass then it cannot have
3419 // declared any inner classes.
3420 ResourceMark rm(THREAD);
3421 Exceptions::fthrow(
3422 THREAD_AND_LOCATION,
3423 vmSymbols::java_lang_IncompatibleClassChangeError(),
3424 "%s and %s disagree on InnerClasses attribute",
3425 ok->external_name(),
3426 external_name());
3427 return nullptr;
3428 }
3429 outer_klass = InstanceKlass::cast(ok);
3430 *inner_is_member = true;
3431 }
3432 if (nullptr == outer_klass) {
3433 // It may be a local class; try for that.
3434 int encl_method_class_idx = enclosing_method_class_index();
3435 if (encl_method_class_idx != 0) {
3436 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3437 outer_klass = InstanceKlass::cast(ok);
3438 *inner_is_member = false;
3439 }
3440 }
3441 }
3442
3443 // If no inner class attribute found for this class.
3444 if (nullptr == outer_klass) return nullptr;
3445
3446 // Throws an exception if outer klass has not declared k as an inner klass
3447 // We need evidence that each klass knows about the other, or else
3448 // the system could allow a spoof of an inner class to gain access rights.
3449 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3450 return outer_klass;
3451 }
3452
3453 jint InstanceKlass::compute_modifier_flags() const {
3454 jint access = access_flags().as_int();
3455
3456 // But check if it happens to be member class.
3457 InnerClassesIterator iter(this);
3458 for (; !iter.done(); iter.next()) {
3459 int ioff = iter.inner_class_info_index();
3460 // Inner class attribute can be zero, skip it.
3461 // Strange but true: JVM spec. allows null inner class refs.
3462 if (ioff == 0) continue;
3463
3464 // only look at classes that are already loaded
3465 // since we are looking for the flags for our self.
3466 Symbol* inner_name = constants()->klass_name_at(ioff);
3467 if (name() == inner_name) {
3468 // This is really a member class.
3469 access = iter.inner_access_flags();
3470 break;
3471 }
3472 }
3473 return (access & JVM_ACC_WRITTEN_FLAGS);
3474 }
3475
3476 jint InstanceKlass::jvmti_class_status() const {
3477 jint result = 0;
3478
3479 if (is_linked()) {
3480 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3481 }
3482
3483 if (is_initialized()) {
3484 assert(is_linked(), "Class status is not consistent");
3485 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3486 }
3487 if (is_in_error_state()) {
3488 result |= JVMTI_CLASS_STATUS_ERROR;
3489 }
3490 return result;
3491 }
3492
3493 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3494 bool implements_interface; // initialized by method_at_itable_or_null
3495 Method* m = method_at_itable_or_null(holder, index,
3496 implements_interface); // out parameter
3497 if (m != nullptr) {
3498 assert(implements_interface, "sanity");
3499 return m;
3500 } else if (implements_interface) {
3501 // Throw AbstractMethodError since corresponding itable slot is empty.
3502 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3503 } else {
3504 // If the interface isn't implemented by the receiver class,
3505 // the VM should throw IncompatibleClassChangeError.
3506 ResourceMark rm(THREAD);
3507 stringStream ss;
3508 bool same_module = (module() == holder->module());
3509 ss.print("Receiver class %s does not implement "
3510 "the interface %s defining the method to be called "
3511 "(%s%s%s)",
3512 external_name(), holder->external_name(),
3513 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3514 (same_module) ? "" : "; ",
3515 (same_module) ? "" : holder->class_in_module_of_loader());
3516 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3517 }
3518 }
3519
3520 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3521 klassItable itable(this);
3522 for (int i = 0; i < itable.size_offset_table(); i++) {
3523 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3524 if (offset_entry->interface_klass() == holder) {
3525 implements_interface = true;
3526 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3527 Method* m = ime[index].method();
3528 return m;
3529 }
3530 }
3531 implements_interface = false;
3532 return nullptr; // offset entry not found
3533 }
3534
3535 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3536 assert(is_linked(), "required");
3537 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3538 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3539
3540 int vtable_index = Method::invalid_vtable_index;
3541 Symbol* name = intf_method->name();
3542 Symbol* signature = intf_method->signature();
3543
3544 // First check in default method array
3545 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3546 int index = find_method_index(default_methods(),
3547 name, signature,
3548 Klass::OverpassLookupMode::find,
3549 Klass::StaticLookupMode::find,
3550 Klass::PrivateLookupMode::find);
3551 if (index >= 0) {
3552 vtable_index = default_vtable_indices()->at(index);
3553 }
3554 }
3555 if (vtable_index == Method::invalid_vtable_index) {
3556 // get vtable_index for miranda methods
3557 klassVtable vt = vtable();
3558 vtable_index = vt.index_of_miranda(name, signature);
3559 }
3560 return vtable_index;
3561 }
3562
3563 #if INCLUDE_JVMTI
3564 // update default_methods for redefineclasses for methods that are
3565 // not yet in the vtable due to concurrent subclass define and superinterface
3566 // redefinition
3567 // Note: those in the vtable, should have been updated via adjust_method_entries
3568 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3569 // search the default_methods for uses of either obsolete or EMCP methods
3570 if (default_methods() != nullptr) {
3571 for (int index = 0; index < default_methods()->length(); index ++) {
3572 Method* old_method = default_methods()->at(index);
3573 if (old_method == nullptr || !old_method->is_old()) {
3574 continue; // skip uninteresting entries
3575 }
3576 assert(!old_method->is_deleted(), "default methods may not be deleted");
3577 Method* new_method = old_method->get_new_method();
3578 default_methods()->at_put(index, new_method);
3579
3580 if (log_is_enabled(Info, redefine, class, update)) {
3581 ResourceMark rm;
3582 if (!(*trace_name_printed)) {
3583 log_info(redefine, class, update)
3584 ("adjust: klassname=%s default methods from name=%s",
3585 external_name(), old_method->method_holder()->external_name());
3586 *trace_name_printed = true;
3587 }
3588 log_debug(redefine, class, update, vtables)
3589 ("default method update: %s(%s) ",
3590 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3591 }
3592 }
3593 }
3594 }
3595 #endif // INCLUDE_JVMTI
3596
3597 // On-stack replacement stuff
3598 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3599 assert_lock_strong(NMethodState_lock);
3600 #ifndef PRODUCT
3601 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3602 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3603 "redundant OSR recompilation detected. memory leak in CodeCache!");
3604 #endif
3605 // only one compilation can be active
3606 assert(n->is_osr_method(), "wrong kind of nmethod");
3607 n->set_osr_link(osr_nmethods_head());
3608 set_osr_nmethods_head(n);
3609 // Raise the highest osr level if necessary
3610 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3611
3612 // Get rid of the osr methods for the same bci that have lower levels.
3613 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3614 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3615 if (inv != nullptr && inv->is_in_use()) {
3616 inv->make_not_entrant();
3617 }
3618 }
3619 }
3620
3621 // Remove osr nmethod from the list. Return true if found and removed.
3622 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3623 // This is a short non-blocking critical region, so the no safepoint check is ok.
3624 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3625 assert(n->is_osr_method(), "wrong kind of nmethod");
3626 nmethod* last = nullptr;
3627 nmethod* cur = osr_nmethods_head();
3628 int max_level = CompLevel_none; // Find the max comp level excluding n
3629 Method* m = n->method();
3630 // Search for match
3631 bool found = false;
3632 while(cur != nullptr && cur != n) {
3633 if (m == cur->method()) {
3634 // Find max level before n
3635 max_level = MAX2(max_level, cur->comp_level());
3636 }
3637 last = cur;
3638 cur = cur->osr_link();
3639 }
3640 nmethod* next = nullptr;
3641 if (cur == n) {
3642 found = true;
3643 next = cur->osr_link();
3644 if (last == nullptr) {
3645 // Remove first element
3646 set_osr_nmethods_head(next);
3647 } else {
3648 last->set_osr_link(next);
3649 }
3650 }
3651 n->set_osr_link(nullptr);
3652 cur = next;
3653 while (cur != nullptr) {
3654 // Find max level after n
3655 if (m == cur->method()) {
3656 max_level = MAX2(max_level, cur->comp_level());
3657 }
3658 cur = cur->osr_link();
3659 }
3660 m->set_highest_osr_comp_level(max_level);
3661 return found;
3662 }
3663
3664 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3665 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3666 nmethod* osr = osr_nmethods_head();
3667 int found = 0;
3668 while (osr != nullptr) {
3669 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3670 if (osr->method() == m) {
3671 deopt_scope->mark(osr);
3672 found++;
3673 }
3674 osr = osr->osr_link();
3675 }
3676 return found;
3677 }
3678
3679 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3680 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
3681 nmethod* osr = osr_nmethods_head();
3682 nmethod* best = nullptr;
3683 while (osr != nullptr) {
3684 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3685 // There can be a time when a c1 osr method exists but we are waiting
3686 // for a c2 version. When c2 completes its osr nmethod we will trash
3687 // the c1 version and only be able to find the c2 version. However
3688 // while we overflow in the c1 code at back branches we don't want to
3689 // try and switch to the same code as we are already running
3690
3691 if (osr->method() == m &&
3692 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3693 if (match_level) {
3694 if (osr->comp_level() == comp_level) {
3695 // Found a match - return it.
3696 return osr;
3697 }
3698 } else {
3699 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3700 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3701 // Found the best possible - return it.
3702 return osr;
3703 }
3704 best = osr;
3705 }
3706 }
3707 }
3708 osr = osr->osr_link();
3709 }
3710
3711 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3712 if (best != nullptr && best->comp_level() >= comp_level) {
3713 return best;
3714 }
3715 return nullptr;
3716 }
3717
3718 // -----------------------------------------------------------------------------------------------------
3719 // Printing
3720
3721 #define BULLET " - "
3722
3723 static const char* state_names[] = {
3724 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3725 };
3726
3727 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3728 ResourceMark rm;
3729 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3730 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3731 for (int i = 0; i < len; i++) {
3732 intptr_t e = start[i];
3733 st->print("%d : " INTPTR_FORMAT, i, e);
3734 if (forward_refs[i] != 0) {
3735 int from = forward_refs[i];
3736 int off = (int) start[from];
3737 st->print(" (offset %d <= [%d])", off, from);
3738 }
3739 if (MetaspaceObj::is_valid((Metadata*)e)) {
3740 st->print(" ");
3741 ((Metadata*)e)->print_value_on(st);
3742 } else if (self != nullptr && e > 0 && e < 0x10000) {
3743 address location = self + e;
3744 int index = (int)((intptr_t*)location - start);
3745 st->print(" (offset %d => [%d])", (int)e, index);
3746 if (index >= 0 && index < len)
3747 forward_refs[index] = i;
3748 }
3749 st->cr();
3750 }
3751 }
3752
3753 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3754 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3755 }
3756
3757 template<typename T>
3758 static void print_array_on(outputStream* st, Array<T>* array) {
3759 if (array == nullptr) { st->print_cr("nullptr"); return; }
3760 array->print_value_on(st); st->cr();
3761 if (Verbose || WizardMode) {
3762 for (int i = 0; i < array->length(); i++) {
3763 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3764 }
3765 }
3766 }
3767
3768 static void print_array_on(outputStream* st, Array<int>* array) {
3769 if (array == nullptr) { st->print_cr("nullptr"); return; }
3770 array->print_value_on(st); st->cr();
3771 if (Verbose || WizardMode) {
3772 for (int i = 0; i < array->length(); i++) {
3773 st->print("%d : %d", i, array->at(i)); st->cr();
3774 }
3775 }
3776 }
3777
3778 const char* InstanceKlass::init_state_name() const {
3779 return state_names[init_state()];
3780 }
3781
3782 void InstanceKlass::print_on(outputStream* st) const {
3783 assert(is_klass(), "must be klass");
3784 Klass::print_on(st);
3785
3786 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3787 st->print(BULLET"klass size: %d", size()); st->cr();
3788 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3789 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3790 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3791 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3792 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3793 st->print(BULLET"sub: ");
3794 Klass* sub = subklass();
3795 int n;
3796 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3797 if (n < MaxSubklassPrintSize) {
3798 sub->print_value_on(st);
3799 st->print(" ");
3800 }
3801 }
3802 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3803 st->cr();
3804
3805 if (is_interface()) {
3806 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3807 if (nof_implementors() == 1) {
3808 st->print_cr(BULLET"implementor: ");
3809 st->print(" ");
3810 implementor()->print_value_on(st);
3811 st->cr();
3812 }
3813 }
3814
3815 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3816 st->print(BULLET"methods: "); print_array_on(st, methods());
3817 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3818 if (default_methods() != nullptr) {
3819 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3820 }
3821 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices());
3822 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3823 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3824
3825 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr();
3826 if (UseSecondarySupersTable) {
3827 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr();
3828 st->print(BULLET"bitmap: " UINTX_FORMAT_X_0, _bitmap); st->cr();
3829 }
3830 if (secondary_supers() != nullptr) {
3831 if (Verbose) {
3832 bool is_hashed = UseSecondarySupersTable && (_bitmap != SECONDARY_SUPERS_BITMAP_FULL);
3833 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length());
3834 for (int i = 0; i < _secondary_supers->length(); i++) {
3835 ResourceMark rm; // for external_name()
3836 Klass* secondary_super = _secondary_supers->at(i);
3837 st->print(BULLET"%2d:", i);
3838 if (is_hashed) {
3839 int home_slot = compute_home_slot(secondary_super, _bitmap);
3840 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK;
3841 st->print(" dist:%02d:", distance);
3842 }
3843 st->print_cr(" %p %s", secondary_super, secondary_super->external_name());
3844 }
3845 }
3846 }
3847 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3848
3849 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data());
3850 print_on_maybe_null(st, BULLET"source file: ", source_file_name());
3851 if (source_debug_extension() != nullptr) {
3852 st->print(BULLET"source debug extension: ");
3853 st->print("%s", source_debug_extension());
3854 st->cr();
3855 }
3856 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations());
3857 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations());
3858 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations());
3859 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations());
3860 {
3861 bool have_pv = false;
3862 // previous versions are linked together through the InstanceKlass
3863 for (InstanceKlass* pv_node = previous_versions();
3864 pv_node != nullptr;
3865 pv_node = pv_node->previous_versions()) {
3866 if (!have_pv)
3867 st->print(BULLET"previous version: ");
3868 have_pv = true;
3869 pv_node->constants()->print_value_on(st);
3870 }
3871 if (have_pv) st->cr();
3872 }
3873
3874 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature());
3875 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3876 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3877 print_on_maybe_null(st, BULLET"record components: ", record_components());
3878 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3879 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr();
3880 if (java_mirror() != nullptr) {
3881 st->print(BULLET"java mirror: ");
3882 java_mirror()->print_value_on(st);
3883 st->cr();
3884 } else {
3885 st->print_cr(BULLET"java mirror: null");
3886 }
3887 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3888 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3889 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3890 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3891 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3892
3893 FieldPrinter print_static_field(st);
3894 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3895 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3896 FieldPrinter print_nonstatic_field(st);
3897 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3898 ik->print_nonstatic_fields(&print_nonstatic_field);
3899
3900 st->print(BULLET"non-static oop maps: ");
3901 OopMapBlock* map = start_of_nonstatic_oop_maps();
3902 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3903 while (map < end_map) {
3904 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3905 map++;
3906 }
3907 st->cr();
3908 }
3909
3910 void InstanceKlass::print_value_on(outputStream* st) const {
3911 assert(is_klass(), "must be klass");
3912 if (Verbose || WizardMode) access_flags().print_on(st);
3913 name()->print_value_on(st);
3914 }
3915
3916 void FieldPrinter::do_field(fieldDescriptor* fd) {
3917 _st->print(BULLET);
3918 if (_obj == nullptr) {
3919 fd->print_on(_st);
3920 _st->cr();
3921 } else {
3922 fd->print_on_for(_st, _obj);
3923 _st->cr();
3924 }
3925 }
3926
3927
3928 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3929 Klass::oop_print_on(obj, st);
3930
3931 if (this == vmClasses::String_klass()) {
3932 typeArrayOop value = java_lang_String::value(obj);
3933 juint length = java_lang_String::length(obj);
3934 if (value != nullptr &&
3935 value->is_typeArray() &&
3936 length <= (juint) value->length()) {
3937 st->print(BULLET"string: ");
3938 java_lang_String::print(obj, st);
3939 st->cr();
3940 }
3941 }
3942
3943 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3944 FieldPrinter print_field(st, obj);
3945 print_nonstatic_fields(&print_field);
3946
3947 if (this == vmClasses::Class_klass()) {
3948 st->print(BULLET"signature: ");
3949 java_lang_Class::print_signature(obj, st);
3950 st->cr();
3951 Klass* real_klass = java_lang_Class::as_Klass(obj);
3952 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3953 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3954 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3955 }
3956 } else if (this == vmClasses::MethodType_klass()) {
3957 st->print(BULLET"signature: ");
3958 java_lang_invoke_MethodType::print_signature(obj, st);
3959 st->cr();
3960 }
3961 }
3962
3963 #ifndef PRODUCT
3964
3965 bool InstanceKlass::verify_itable_index(int i) {
3966 int method_count = klassItable::method_count_for_interface(this);
3967 assert(i >= 0 && i < method_count, "index out of bounds");
3968 return true;
3969 }
3970
3971 #endif //PRODUCT
3972
3973 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3974 st->print("a ");
3975 name()->print_value_on(st);
3976 obj->print_address_on(st);
3977 if (this == vmClasses::String_klass()
3978 && java_lang_String::value(obj) != nullptr) {
3979 ResourceMark rm;
3980 int len = java_lang_String::length(obj);
3981 int plen = (len < 24 ? len : 12);
3982 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3983 st->print(" = \"%s\"", str);
3984 if (len > plen)
3985 st->print("...[%d]", len);
3986 } else if (this == vmClasses::Class_klass()) {
3987 Klass* k = java_lang_Class::as_Klass(obj);
3988 st->print(" = ");
3989 if (k != nullptr) {
3990 k->print_value_on(st);
3991 } else {
3992 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3993 st->print("%s", tname ? tname : "type?");
3994 }
3995 } else if (this == vmClasses::MethodType_klass()) {
3996 st->print(" = ");
3997 java_lang_invoke_MethodType::print_signature(obj, st);
3998 } else if (java_lang_boxing_object::is_instance(obj)) {
3999 st->print(" = ");
4000 java_lang_boxing_object::print(obj, st);
4001 } else if (this == vmClasses::LambdaForm_klass()) {
4002 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4003 if (vmentry != nullptr) {
4004 st->print(" => ");
4005 vmentry->print_value_on(st);
4006 }
4007 } else if (this == vmClasses::MemberName_klass()) {
4008 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4009 if (vmtarget != nullptr) {
4010 st->print(" = ");
4011 vmtarget->print_value_on(st);
4012 } else {
4013 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4014 oop name = java_lang_invoke_MemberName::name(obj);
4015 if (clazz != nullptr) {
4016 clazz->print_value_on(st);
4017 } else {
4018 st->print("null");
4019 }
4020 st->print(".");
4021 if (name != nullptr) {
4022 name->print_value_on(st);
4023 } else {
4024 st->print("null");
4025 }
4026 }
4027 }
4028 }
4029
4030 const char* InstanceKlass::internal_name() const {
4031 return external_name();
4032 }
4033
4034 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4035 const ModuleEntry* module_entry,
4036 const ClassFileStream* cfs) const {
4037
4038 if (ClassListWriter::is_enabled()) {
4039 ClassListWriter::write(this, cfs);
4040 }
4041
4042 print_class_load_helper(loader_data, module_entry, cfs);
4043 print_class_load_cause_logging();
4044 }
4045
4046 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4047 const ModuleEntry* module_entry,
4048 const ClassFileStream* cfs) const {
4049
4050 if (!log_is_enabled(Info, class, load)) {
4051 return;
4052 }
4053
4054 ResourceMark rm;
4055 LogMessage(class, load) msg;
4056 stringStream info_stream;
4057
4058 // Name and class hierarchy info
4059 info_stream.print("%s", external_name());
4060
4061 // Source
4062 if (cfs != nullptr) {
4063 if (cfs->source() != nullptr) {
4064 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4065 if (module_name != nullptr) {
4066 // When the boot loader created the stream, it didn't know the module name
4067 // yet. Let's format it now.
4068 if (cfs->from_boot_loader_modules_image()) {
4069 info_stream.print(" source: jrt:/%s", module_name);
4070 } else {
4071 info_stream.print(" source: %s", cfs->source());
4072 }
4073 } else {
4074 info_stream.print(" source: %s", cfs->source());
4075 }
4076 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4077 Thread* current = Thread::current();
4078 Klass* caller = current->is_Java_thread() ?
4079 JavaThread::cast(current)->security_get_caller_class(1):
4080 nullptr;
4081 // caller can be null, for example, during a JVMTI VM_Init hook
4082 if (caller != nullptr) {
4083 info_stream.print(" source: instance of %s", caller->external_name());
4084 } else {
4085 // source is unknown
4086 }
4087 } else {
4088 oop class_loader = loader_data->class_loader();
4089 info_stream.print(" source: %s", class_loader->klass()->external_name());
4090 }
4091 } else {
4092 assert(this->is_shared(), "must be");
4093 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4094 info_stream.print(" source: shared objects file (top)");
4095 } else {
4096 info_stream.print(" source: shared objects file");
4097 }
4098 }
4099
4100 msg.info("%s", info_stream.as_string());
4101
4102 if (log_is_enabled(Debug, class, load)) {
4103 stringStream debug_stream;
4104
4105 // Class hierarchy info
4106 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4107 p2i(this), p2i(superklass()));
4108
4109 // Interfaces
4110 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4111 debug_stream.print(" interfaces:");
4112 int length = local_interfaces()->length();
4113 for (int i = 0; i < length; i++) {
4114 debug_stream.print(" " PTR_FORMAT,
4115 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4116 }
4117 }
4118
4119 // Class loader
4120 debug_stream.print(" loader: [");
4121 loader_data->print_value_on(&debug_stream);
4122 debug_stream.print("]");
4123
4124 // Classfile checksum
4125 if (cfs) {
4126 debug_stream.print(" bytes: %d checksum: %08x",
4127 cfs->length(),
4128 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4129 cfs->length()));
4130 }
4131
4132 msg.debug("%s", debug_stream.as_string());
4133 }
4134 }
4135
4136 void InstanceKlass::print_class_load_cause_logging() const {
4137 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4138 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4139 JavaThread* current = JavaThread::current();
4140 ResourceMark rm(current);
4141 const char* name = external_name();
4142
4143 if (LogClassLoadingCauseFor == nullptr ||
4144 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4145 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4146 return;
4147 }
4148
4149 // Log Java stack first
4150 {
4151 LogMessage(class, load, cause) msg;
4152 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4153
4154 info_stream.print_cr("Java stack when loading %s:", name);
4155 current->print_stack_on(&info_stream);
4156 }
4157
4158 // Log native stack second
4159 if (log_cause_native) {
4160 // Log to string first so that lines can be indented
4161 stringStream stack_stream;
4162 char buf[O_BUFLEN];
4163 address lastpc = nullptr;
4164 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4165 // We have printed the native stack in platform-specific code,
4166 // so nothing else to do in this case.
4167 } else {
4168 frame f = os::current_frame();
4169 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4170 -1 /* max stack_stream */, buf, O_BUFLEN);
4171 }
4172
4173 LogMessage(class, load, cause, native) msg;
4174 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4175 info_stream.print_cr("Native stack when loading %s:", name);
4176
4177 // Print each native stack line to the log
4178 int size = (int) stack_stream.size();
4179 char* stack = stack_stream.as_string();
4180 char* stack_end = stack + size;
4181 char* line_start = stack;
4182 for (char* p = stack; p < stack_end; p++) {
4183 if (*p == '\n') {
4184 *p = '\0';
4185 info_stream.print_cr("\t%s", line_start);
4186 line_start = p + 1;
4187 }
4188 }
4189 if (line_start < stack_end) {
4190 info_stream.print_cr("\t%s", line_start);
4191 }
4192 }
4193 }
4194 }
4195
4196 // Verification
4197
4198 class VerifyFieldClosure: public BasicOopIterateClosure {
4199 protected:
4200 template <class T> void do_oop_work(T* p) {
4201 oop obj = RawAccess<>::oop_load(p);
4202 if (!oopDesc::is_oop_or_null(obj)) {
4203 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4204 Universe::print_on(tty);
4205 guarantee(false, "boom");
4206 }
4207 }
4208 public:
4209 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4210 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4211 };
4212
4213 void InstanceKlass::verify_on(outputStream* st) {
4214 #ifndef PRODUCT
4215 // Avoid redundant verifies, this really should be in product.
4216 if (_verify_count == Universe::verify_count()) return;
4217 _verify_count = Universe::verify_count();
4218 #endif
4219
4220 // Verify Klass
4221 Klass::verify_on(st);
4222
4223 // Verify that klass is present in ClassLoaderData
4224 guarantee(class_loader_data()->contains_klass(this),
4225 "this class isn't found in class loader data");
4226
4227 // Verify vtables
4228 if (is_linked()) {
4229 // $$$ This used to be done only for m/s collections. Doing it
4230 // always seemed a valid generalization. (DLD -- 6/00)
4231 vtable().verify(st);
4232 }
4233
4234 // Verify first subklass
4235 if (subklass() != nullptr) {
4236 guarantee(subklass()->is_klass(), "should be klass");
4237 }
4238
4239 // Verify siblings
4240 Klass* super = this->super();
4241 Klass* sib = next_sibling();
4242 if (sib != nullptr) {
4243 if (sib == this) {
4244 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4245 }
4246
4247 guarantee(sib->is_klass(), "should be klass");
4248 guarantee(sib->super() == super, "siblings should have same superklass");
4249 }
4250
4251 // Verify local interfaces
4252 if (local_interfaces()) {
4253 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4254 for (int j = 0; j < local_interfaces->length(); j++) {
4255 InstanceKlass* e = local_interfaces->at(j);
4256 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4257 }
4258 }
4259
4260 // Verify transitive interfaces
4261 if (transitive_interfaces() != nullptr) {
4262 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4263 for (int j = 0; j < transitive_interfaces->length(); j++) {
4264 InstanceKlass* e = transitive_interfaces->at(j);
4265 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4266 }
4267 }
4268
4269 // Verify methods
4270 if (methods() != nullptr) {
4271 Array<Method*>* methods = this->methods();
4272 for (int j = 0; j < methods->length(); j++) {
4273 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4274 }
4275 for (int j = 0; j < methods->length() - 1; j++) {
4276 Method* m1 = methods->at(j);
4277 Method* m2 = methods->at(j + 1);
4278 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4279 }
4280 }
4281
4282 // Verify method ordering
4283 if (method_ordering() != nullptr) {
4284 Array<int>* method_ordering = this->method_ordering();
4285 int length = method_ordering->length();
4286 if (JvmtiExport::can_maintain_original_method_order() ||
4287 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) {
4288 guarantee(length == methods()->length(), "invalid method ordering length");
4289 jlong sum = 0;
4290 for (int j = 0; j < length; j++) {
4291 int original_index = method_ordering->at(j);
4292 guarantee(original_index >= 0, "invalid method ordering index");
4293 guarantee(original_index < length, "invalid method ordering index");
4294 sum += original_index;
4295 }
4296 // Verify sum of indices 0,1,...,length-1
4297 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4298 } else {
4299 guarantee(length == 0, "invalid method ordering length");
4300 }
4301 }
4302
4303 // Verify default methods
4304 if (default_methods() != nullptr) {
4305 Array<Method*>* methods = this->default_methods();
4306 for (int j = 0; j < methods->length(); j++) {
4307 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4308 }
4309 for (int j = 0; j < methods->length() - 1; j++) {
4310 Method* m1 = methods->at(j);
4311 Method* m2 = methods->at(j + 1);
4312 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4313 }
4314 }
4315
4316 // Verify JNI static field identifiers
4317 if (jni_ids() != nullptr) {
4318 jni_ids()->verify(this);
4319 }
4320
4321 // Verify other fields
4322 if (constants() != nullptr) {
4323 guarantee(constants()->is_constantPool(), "should be constant pool");
4324 }
4325 }
4326
4327 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4328 Klass::oop_verify_on(obj, st);
4329 VerifyFieldClosure blk;
4330 obj->oop_iterate(&blk);
4331 }
4332
4333
4334 // JNIid class for jfieldIDs only
4335 // Note to reviewers:
4336 // These JNI functions are just moved over to column 1 and not changed
4337 // in the compressed oops workspace.
4338 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4339 _holder = holder;
4340 _offset = offset;
4341 _next = next;
4342 debug_only(_is_static_field_id = false;)
4343 }
4344
4345
4346 JNIid* JNIid::find(int offset) {
4347 JNIid* current = this;
4348 while (current != nullptr) {
4349 if (current->offset() == offset) return current;
4350 current = current->next();
4351 }
4352 return nullptr;
4353 }
4354
4355 void JNIid::deallocate(JNIid* current) {
4356 while (current != nullptr) {
4357 JNIid* next = current->next();
4358 delete current;
4359 current = next;
4360 }
4361 }
4362
4363
4364 void JNIid::verify(Klass* holder) {
4365 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4366 int end_field_offset;
4367 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4368
4369 JNIid* current = this;
4370 while (current != nullptr) {
4371 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4372 #ifdef ASSERT
4373 int o = current->offset();
4374 if (current->is_static_field_id()) {
4375 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4376 }
4377 #endif
4378 current = current->next();
4379 }
4380 }
4381
4382 void InstanceKlass::set_init_state(ClassState state) {
4383 #ifdef ASSERT
4384 bool good_state = is_shared() ? (_init_state <= state)
4385 : (_init_state < state);
4386 assert(good_state || state == allocated, "illegal state transition");
4387 #endif
4388 assert(_init_thread == nullptr, "should be cleared before state change");
4389 Atomic::release_store(&_init_state, state);
4390 }
4391
4392 #if INCLUDE_JVMTI
4393
4394 // RedefineClasses() support for previous versions
4395
4396 // Globally, there is at least one previous version of a class to walk
4397 // during class unloading, which is saved because old methods in the class
4398 // are still running. Otherwise the previous version list is cleaned up.
4399 bool InstanceKlass::_should_clean_previous_versions = false;
4400
4401 // Returns true if there are previous versions of a class for class
4402 // unloading only. Also resets the flag to false. purge_previous_version
4403 // will set the flag to true if there are any left, i.e., if there's any
4404 // work to do for next time. This is to avoid the expensive code cache
4405 // walk in CLDG::clean_deallocate_lists().
4406 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4407 bool ret = _should_clean_previous_versions;
4408 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4409 ret ? "true" : "false");
4410 _should_clean_previous_versions = false;
4411 return ret;
4412 }
4413
4414 // This nulls out jmethodIDs for all methods in 'klass'
4415 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
4416 // during class unloading.
4417 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions
4418 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
4419 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
4420 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
4421 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
4422 Array<Method*>* method_refs = klass->methods();
4423 for (int k = 0; k < method_refs->length(); k++) {
4424 Method* method = method_refs->at(k);
4425 if (method != nullptr && method->is_obsolete()) {
4426 method->clear_jmethod_id();
4427 }
4428 }
4429 }
4430
4431 // Purge previous versions before adding new previous versions of the class and
4432 // during class unloading.
4433 void InstanceKlass::purge_previous_version_list() {
4434 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4435 assert(has_been_redefined(), "Should only be called for main class");
4436
4437 // Quick exit.
4438 if (previous_versions() == nullptr) {
4439 return;
4440 }
4441
4442 // This klass has previous versions so see what we can cleanup
4443 // while it is safe to do so.
4444
4445 int deleted_count = 0; // leave debugging breadcrumbs
4446 int live_count = 0;
4447 ClassLoaderData* loader_data = class_loader_data();
4448 assert(loader_data != nullptr, "should never be null");
4449
4450 ResourceMark rm;
4451 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4452
4453 // previous versions are linked together through the InstanceKlass
4454 InstanceKlass* pv_node = previous_versions();
4455 InstanceKlass* last = this;
4456 int version = 0;
4457
4458 // check the previous versions list
4459 for (; pv_node != nullptr; ) {
4460
4461 ConstantPool* pvcp = pv_node->constants();
4462 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4463
4464 if (!pvcp->on_stack()) {
4465 // If the constant pool isn't on stack, none of the methods
4466 // are executing. Unlink this previous_version.
4467 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4468 // so will be deallocated during the next phase of class unloading.
4469 log_trace(redefine, class, iklass, purge)
4470 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4471 // Unlink from previous version list.
4472 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4473 InstanceKlass* next = pv_node->previous_versions();
4474 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
4475 pv_node->link_previous_versions(nullptr); // point next to null
4476 last->link_previous_versions(next);
4477 // Delete this node directly. Nothing is referring to it and we don't
4478 // want it to increase the counter for metadata to delete in CLDG.
4479 MetadataFactory::free_metadata(loader_data, pv_node);
4480 pv_node = next;
4481 deleted_count++;
4482 version++;
4483 continue;
4484 } else {
4485 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4486 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4487 live_count++;
4488 if (pvcp->is_shared()) {
4489 // Shared previous versions can never be removed so no cleaning is needed.
4490 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4491 } else {
4492 // Previous version alive, set that clean is needed for next time.
4493 _should_clean_previous_versions = true;
4494 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4495 }
4496 }
4497
4498 // next previous version
4499 last = pv_node;
4500 pv_node = pv_node->previous_versions();
4501 version++;
4502 }
4503 log_trace(redefine, class, iklass, purge)
4504 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4505 }
4506
4507 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4508 int emcp_method_count) {
4509 int obsolete_method_count = old_methods->length() - emcp_method_count;
4510
4511 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4512 _previous_versions != nullptr) {
4513 // We have a mix of obsolete and EMCP methods so we have to
4514 // clear out any matching EMCP method entries the hard way.
4515 int local_count = 0;
4516 for (int i = 0; i < old_methods->length(); i++) {
4517 Method* old_method = old_methods->at(i);
4518 if (old_method->is_obsolete()) {
4519 // only obsolete methods are interesting
4520 Symbol* m_name = old_method->name();
4521 Symbol* m_signature = old_method->signature();
4522
4523 // previous versions are linked together through the InstanceKlass
4524 int j = 0;
4525 for (InstanceKlass* prev_version = _previous_versions;
4526 prev_version != nullptr;
4527 prev_version = prev_version->previous_versions(), j++) {
4528
4529 Array<Method*>* method_refs = prev_version->methods();
4530 for (int k = 0; k < method_refs->length(); k++) {
4531 Method* method = method_refs->at(k);
4532
4533 if (!method->is_obsolete() &&
4534 method->name() == m_name &&
4535 method->signature() == m_signature) {
4536 // The current RedefineClasses() call has made all EMCP
4537 // versions of this method obsolete so mark it as obsolete
4538 log_trace(redefine, class, iklass, add)
4539 ("%s(%s): flush obsolete method @%d in version @%d",
4540 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4541
4542 method->set_is_obsolete();
4543 break;
4544 }
4545 }
4546
4547 // The previous loop may not find a matching EMCP method, but
4548 // that doesn't mean that we can optimize and not go any
4549 // further back in the PreviousVersion generations. The EMCP
4550 // method for this generation could have already been made obsolete,
4551 // but there still may be an older EMCP method that has not
4552 // been made obsolete.
4553 }
4554
4555 if (++local_count >= obsolete_method_count) {
4556 // no more obsolete methods so bail out now
4557 break;
4558 }
4559 }
4560 }
4561 }
4562 }
4563
4564 // Save the scratch_class as the previous version if any of the methods are running.
4565 // The previous_versions are used to set breakpoints in EMCP methods and they are
4566 // also used to clean MethodData links to redefined methods that are no longer running.
4567 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4568 int emcp_method_count) {
4569 assert(Thread::current()->is_VM_thread(),
4570 "only VMThread can add previous versions");
4571
4572 ResourceMark rm;
4573 log_trace(redefine, class, iklass, add)
4574 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4575
4576 // Clean out old previous versions for this class
4577 purge_previous_version_list();
4578
4579 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4580 // a previous redefinition may be made obsolete by this redefinition.
4581 Array<Method*>* old_methods = scratch_class->methods();
4582 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4583
4584 // If the constant pool for this previous version of the class
4585 // is not marked as being on the stack, then none of the methods
4586 // in this previous version of the class are on the stack so
4587 // we don't need to add this as a previous version.
4588 ConstantPool* cp_ref = scratch_class->constants();
4589 if (!cp_ref->on_stack()) {
4590 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4591 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4592 return;
4593 }
4594
4595 // Add previous version if any methods are still running or if this is
4596 // a shared class which should never be removed.
4597 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4598 scratch_class->link_previous_versions(previous_versions());
4599 link_previous_versions(scratch_class);
4600 if (cp_ref->is_shared()) {
4601 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4602 } else {
4603 // We only set clean_previous_versions flag for processing during class
4604 // unloading for non-shared classes.
4605 _should_clean_previous_versions = true;
4606 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4607 }
4608 } // end add_previous_version()
4609
4610 #endif // INCLUDE_JVMTI
4611
4612 Method* InstanceKlass::method_with_idnum(int idnum) {
4613 Method* m = nullptr;
4614 if (idnum < methods()->length()) {
4615 m = methods()->at(idnum);
4616 }
4617 if (m == nullptr || m->method_idnum() != idnum) {
4618 for (int index = 0; index < methods()->length(); ++index) {
4619 m = methods()->at(index);
4620 if (m->method_idnum() == idnum) {
4621 return m;
4622 }
4623 }
4624 // None found, return null for the caller to handle.
4625 return nullptr;
4626 }
4627 return m;
4628 }
4629
4630
4631 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4632 if (idnum >= methods()->length()) {
4633 return nullptr;
4634 }
4635 Method* m = methods()->at(idnum);
4636 if (m != nullptr && m->orig_method_idnum() == idnum) {
4637 return m;
4638 }
4639 // Obsolete method idnum does not match the original idnum
4640 for (int index = 0; index < methods()->length(); ++index) {
4641 m = methods()->at(index);
4642 if (m->orig_method_idnum() == idnum) {
4643 return m;
4644 }
4645 }
4646 // None found, return null for the caller to handle.
4647 return nullptr;
4648 }
4649
4650
4651 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4652 InstanceKlass* holder = get_klass_version(version);
4653 if (holder == nullptr) {
4654 return nullptr; // The version of klass is gone, no method is found
4655 }
4656 Method* method = holder->method_with_orig_idnum(idnum);
4657 return method;
4658 }
4659
4660 #if INCLUDE_JVMTI
4661 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4662 return _cached_class_file;
4663 }
4664
4665 jint InstanceKlass::get_cached_class_file_len() {
4666 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4667 }
4668
4669 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4670 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4671 }
4672 #endif
4673
4674 // Make a step iterating over the class hierarchy under the root class.
4675 // Skips subclasses if requested.
4676 void ClassHierarchyIterator::next() {
4677 assert(_current != nullptr, "required");
4678 if (_visit_subclasses && _current->subklass() != nullptr) {
4679 _current = _current->subklass();
4680 return; // visit next subclass
4681 }
4682 _visit_subclasses = true; // reset
4683 while (_current->next_sibling() == nullptr && _current != _root) {
4684 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4685 }
4686 if (_current == _root) {
4687 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4688 _current = nullptr;
4689 return;
4690 }
4691 _current = _current->next_sibling();
4692 return; // visit next sibling subclass
4693 }