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