1 /*
2 * Copyright (c) 1997, 2021, 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 "jvm.h"
27 #include "cds/archiveUtils.hpp"
28 #include "cds/classListWriter.hpp"
29 #include "cds/metaspaceShared.hpp"
30 #include "classfile/classFileParser.hpp"
31 #include "classfile/classFileStream.hpp"
32 #include "classfile/classLoader.hpp"
33 #include "classfile/classLoaderData.inline.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/moduleEntry.hpp"
36 #include "classfile/resolutionErrors.hpp"
37 #include "classfile/symbolTable.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/oopMapCache.hpp"
49 #include "interpreter/rewriter.hpp"
50 #include "jvmtifiles/jvmti.h"
51 #include "logging/log.hpp"
52 #include "logging/logMessage.hpp"
53 #include "logging/logStream.hpp"
54 #include "memory/allocation.inline.hpp"
55 #include "memory/iterator.inline.hpp"
56 #include "memory/metadataFactory.hpp"
57 #include "memory/metaspaceClosure.hpp"
58 #include "memory/oopFactory.hpp"
59 #include "memory/resourceArea.hpp"
60 #include "memory/universe.hpp"
61 #include "oops/fieldStreams.inline.hpp"
62 #include "oops/constantPool.hpp"
63 #include "oops/instanceClassLoaderKlass.hpp"
64 #include "oops/instanceKlass.inline.hpp"
65 #include "oops/instanceMirrorKlass.hpp"
66 #include "oops/instanceOop.hpp"
67 #include "oops/klass.inline.hpp"
68 #include "oops/method.hpp"
69 #include "oops/oop.inline.hpp"
70 #include "oops/recordComponent.hpp"
71 #include "oops/symbol.hpp"
72 #include "prims/jvmtiExport.hpp"
73 #include "prims/jvmtiRedefineClasses.hpp"
74 #include "prims/jvmtiThreadState.hpp"
75 #include "prims/methodComparator.hpp"
76 #include "runtime/arguments.hpp"
77 #include "runtime/atomic.hpp"
78 #include "runtime/fieldDescriptor.inline.hpp"
79 #include "runtime/handles.inline.hpp"
80 #include "runtime/javaCalls.hpp"
81 #include "runtime/mutexLocker.hpp"
82 #include "runtime/orderAccess.hpp"
83 #include "runtime/reflectionUtils.hpp"
84 #include "runtime/thread.inline.hpp"
85 #include "services/classLoadingService.hpp"
86 #include "services/threadService.hpp"
87 #include "utilities/dtrace.hpp"
88 #include "utilities/events.hpp"
89 #include "utilities/macros.hpp"
90 #include "utilities/stringUtils.hpp"
91 #include "utilities/pair.hpp"
92 #ifdef COMPILER1
93 #include "c1/c1_Compiler.hpp"
94 #endif
95 #if INCLUDE_JFR
96 #include "jfr/jfrEvents.hpp"
97 #endif
98
99
100 #ifdef DTRACE_ENABLED
101
102
103 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
104 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
105 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
106 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
107 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
108 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
109 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
110 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
111 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
112 { \
113 char* data = NULL; \
114 int len = 0; \
115 Symbol* clss_name = name(); \
116 if (clss_name != NULL) { \
117 data = (char*)clss_name->bytes(); \
118 len = clss_name->utf8_length(); \
119 } \
120 HOTSPOT_CLASS_INITIALIZATION_##type( \
121 data, len, (void*)class_loader(), thread_type); \
122 }
123
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
125 { \
126 char* data = NULL; \
127 int len = 0; \
128 Symbol* clss_name = name(); \
129 if (clss_name != NULL) { \
130 data = (char*)clss_name->bytes(); \
131 len = clss_name->utf8_length(); \
132 } \
133 HOTSPOT_CLASS_INITIALIZATION_##type( \
134 data, len, (void*)class_loader(), thread_type, wait); \
135 }
136
137 #else // ndef DTRACE_ENABLED
138
139 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
140 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
141
142 #endif // ndef DTRACE_ENABLED
143
144
145 static inline bool is_class_loader(const Symbol* class_name,
146 const ClassFileParser& parser) {
147 assert(class_name != NULL, "invariant");
148
149 if (class_name == vmSymbols::java_lang_ClassLoader()) {
150 return true;
151 }
152
153 if (vmClasses::ClassLoader_klass_loaded()) {
154 const Klass* const super_klass = parser.super_klass();
155 if (super_klass != NULL) {
156 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
157 return true;
158 }
159 }
160 }
161 return false;
162 }
163
164 // private: called to verify that k is a static member of this nest.
165 // We know that k is an instance class in the same package and hence the
166 // same classloader.
167 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
168 assert(!is_hidden(), "unexpected hidden class");
169 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
170 if (log_is_enabled(Trace, class, nestmates)) {
171 ResourceMark rm(current);
172 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
173 k->external_name(), this->external_name());
174 }
175 return false;
176 }
177
178 if (log_is_enabled(Trace, class, nestmates)) {
179 ResourceMark rm(current);
180 log_trace(class, nestmates)("Checking nest membership of %s in %s",
181 k->external_name(), this->external_name());
182 }
183
184 // Check for the named class in _nest_members.
185 // We don't resolve, or load, any classes.
186 for (int i = 0; i < _nest_members->length(); i++) {
187 int cp_index = _nest_members->at(i);
188 Symbol* name = _constants->klass_name_at(cp_index);
189 if (name == k->name()) {
190 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
191 return true;
192 }
193 }
194 log_trace(class, nestmates)("- class is NOT a nest member!");
195 return false;
196 }
197
198 // Called to verify that k is a permitted subclass of this class
199 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
200 Thread* current = Thread::current();
201 assert(k != NULL, "sanity check");
202 assert(_permitted_subclasses != NULL && _permitted_subclasses != Universe::the_empty_short_array(),
203 "unexpected empty _permitted_subclasses array");
204
205 if (log_is_enabled(Trace, class, sealed)) {
206 ResourceMark rm(current);
207 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
208 k->external_name(), this->external_name());
209 }
210
211 // Check that the class and its super are in the same module.
212 if (k->module() != this->module()) {
213 ResourceMark rm(current);
214 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
215 k->external_name(), this->external_name());
216 return false;
217 }
218
219 if (!k->is_public() && !is_same_class_package(k)) {
220 ResourceMark rm(current);
221 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
222 k->external_name(), this->external_name());
223 return false;
224 }
225
226 for (int i = 0; i < _permitted_subclasses->length(); i++) {
227 int cp_index = _permitted_subclasses->at(i);
228 Symbol* name = _constants->klass_name_at(cp_index);
229 if (name == k->name()) {
230 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
231 return true;
232 }
233 }
234 log_trace(class, sealed)("- class is NOT a permitted subclass!");
235 return false;
236 }
237
238 // Return nest-host class, resolving, validating and saving it if needed.
239 // In cases where this is called from a thread that cannot do classloading
240 // (such as a native JIT thread) then we simply return NULL, which in turn
241 // causes the access check to return false. Such code will retry the access
242 // from a more suitable environment later. Otherwise the _nest_host is always
243 // set once this method returns.
244 // Any errors from nest-host resolution must be preserved so they can be queried
245 // from higher-level access checking code, and reported as part of access checking
246 // exceptions.
247 // VirtualMachineErrors are propagated with a NULL return.
248 // Under any conditions where the _nest_host can be set to non-NULL the resulting
249 // value of it and, if applicable, the nest host resolution/validation error,
250 // are idempotent.
251 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
252 InstanceKlass* nest_host_k = _nest_host;
253 if (nest_host_k != NULL) {
254 return nest_host_k;
255 }
256
257 ResourceMark rm(THREAD);
258
259 // need to resolve and save our nest-host class.
260 if (_nest_host_index != 0) { // we have a real nest_host
261 // Before trying to resolve check if we're in a suitable context
262 bool can_resolve = THREAD->can_call_java();
263 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
264 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
265 this->external_name());
266 return NULL; // sentinel to say "try again from a different context"
267 }
268
269 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
270 this->external_name(),
271 _constants->klass_name_at(_nest_host_index)->as_C_string());
272
273 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
274 if (HAS_PENDING_EXCEPTION) {
275 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
276 return NULL; // propagate VMEs
277 }
278 stringStream ss;
279 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
280 ss.print("Nest host resolution of %s with host %s failed: ",
281 this->external_name(), target_host_class);
282 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
283 const char* msg = ss.as_string(true /* on C-heap */);
284 constantPoolHandle cph(THREAD, constants());
285 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
286 CLEAR_PENDING_EXCEPTION;
287
288 log_trace(class, nestmates)("%s", msg);
289 } else {
290 // A valid nest-host is an instance class in the current package that lists this
291 // class as a nest member. If any of these conditions are not met the class is
292 // its own nest-host.
293 const char* error = NULL;
294
295 // JVMS 5.4.4 indicates package check comes first
296 if (is_same_class_package(k)) {
297 // Now check actual membership. We can't be a member if our "host" is
298 // not an instance class.
299 if (k->is_instance_klass()) {
300 nest_host_k = InstanceKlass::cast(k);
301 bool is_member = nest_host_k->has_nest_member(THREAD, this);
302 if (is_member) {
303 _nest_host = nest_host_k; // save resolved nest-host value
304
305 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
306 this->external_name(), k->external_name());
307 return nest_host_k;
308 } else {
309 error = "current type is not listed as a nest member";
310 }
311 } else {
312 error = "host is not an instance class";
313 }
314 } else {
315 error = "types are in different packages";
316 }
317
318 // something went wrong, so record what and log it
319 {
320 stringStream ss;
321 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
322 this->external_name(),
323 this->class_loader_data()->loader_name_and_id(),
324 k->external_name(),
325 k->class_loader_data()->loader_name_and_id(),
326 error);
327 const char* msg = ss.as_string(true /* on C-heap */);
328 constantPoolHandle cph(THREAD, constants());
329 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
330 log_trace(class, nestmates)("%s", msg);
331 }
332 }
333 } else {
334 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
335 this->external_name());
336 }
337
338 // Either not in an explicit nest, or else an error occurred, so
339 // the nest-host is set to `this`. Any thread that sees this assignment
340 // will also see any setting of nest_host_error(), if applicable.
341 return (_nest_host = this);
342 }
343
344 // Dynamic nest member support: set this class's nest host to the given class.
345 // This occurs as part of the class definition, as soon as the instanceKlass
346 // has been created and doesn't require further resolution. The code:
347 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
348 // results in:
349 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
350 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
351 // We also know the "host" is a valid nest-host in the same package so we can
352 // assert some of those facts.
353 void InstanceKlass::set_nest_host(InstanceKlass* host) {
354 assert(is_hidden(), "must be a hidden class");
355 assert(host != NULL, "NULL nest host specified");
356 assert(_nest_host == NULL, "current class has resolved nest-host");
357 assert(nest_host_error() == NULL, "unexpected nest host resolution error exists: %s",
358 nest_host_error());
359 assert((host->_nest_host == NULL && host->_nest_host_index == 0) ||
360 (host->_nest_host == host), "proposed host is not a valid nest-host");
361 // Can't assert this as package is not set yet:
362 // assert(is_same_class_package(host), "proposed host is in wrong package");
363
364 if (log_is_enabled(Trace, class, nestmates)) {
365 ResourceMark rm;
366 const char* msg = "";
367 // a hidden class does not expect a statically defined nest-host
368 if (_nest_host_index > 0) {
369 msg = "(the NestHost attribute in the current class is ignored)";
370 } else if (_nest_members != NULL && _nest_members != Universe::the_empty_short_array()) {
371 msg = "(the NestMembers attribute in the current class is ignored)";
372 }
373 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
374 this->external_name(),
375 host->external_name(),
376 msg);
377 }
378 // set dynamic nest host
379 _nest_host = host;
380 // Record dependency to keep nest host from being unloaded before this class.
381 ClassLoaderData* this_key = class_loader_data();
382 this_key->record_dependency(host);
383 }
384
385 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
386 // or we are k's nest_host - all of which is covered by comparing the two
387 // resolved_nest_hosts.
388 // Any exceptions (i.e. VMEs) are propagated.
389 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
390
391 assert(this != k, "this should be handled by higher-level code");
392
393 // Per JVMS 5.4.4 we first resolve and validate the current class, then
394 // the target class k.
395
396 InstanceKlass* cur_host = nest_host(CHECK_false);
397 if (cur_host == NULL) {
398 return false;
399 }
400
401 Klass* k_nest_host = k->nest_host(CHECK_false);
402 if (k_nest_host == NULL) {
403 return false;
404 }
405
406 bool access = (cur_host == k_nest_host);
407
408 ResourceMark rm(THREAD);
409 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
410 this->external_name(),
411 access ? "" : "NOT ",
412 k->external_name());
413 return access;
414 }
415
416 const char* InstanceKlass::nest_host_error() {
417 if (_nest_host_index == 0) {
418 return NULL;
419 } else {
420 constantPoolHandle cph(Thread::current(), constants());
421 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
422 }
423 }
424
425 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
426 const int size = InstanceKlass::size(parser.vtable_size(),
427 parser.itable_size(),
428 nonstatic_oop_map_size(parser.total_oop_map_count()),
429 parser.is_interface());
430
431 const Symbol* const class_name = parser.class_name();
432 assert(class_name != NULL, "invariant");
433 ClassLoaderData* loader_data = parser.loader_data();
434 assert(loader_data != NULL, "invariant");
435
436 InstanceKlass* ik;
437
438 // Allocation
439 if (REF_NONE == parser.reference_type()) {
440 if (class_name == vmSymbols::java_lang_Class()) {
441 // mirror
442 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
443 }
444 else if (is_class_loader(class_name, parser)) {
445 // class loader
446 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
447 } else {
448 // normal
449 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_kind_other);
450 }
451 } else {
452 // reference
453 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
454 }
455
456 // Check for pending exception before adding to the loader data and incrementing
457 // class count. Can get OOM here.
458 if (HAS_PENDING_EXCEPTION) {
459 return NULL;
460 }
461
462 return ik;
463 }
464
465
466 // copy method ordering from resource area to Metaspace
467 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
468 if (m != NULL) {
469 // allocate a new array and copy contents (memcpy?)
470 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
471 for (int i = 0; i < m->length(); i++) {
472 _method_ordering->at_put(i, m->at(i));
473 }
474 } else {
475 _method_ordering = Universe::the_empty_int_array();
476 }
477 }
478
479 // create a new array of vtable_indices for default methods
480 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
481 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
482 assert(default_vtable_indices() == NULL, "only create once");
483 set_default_vtable_indices(vtable_indices);
484 return vtable_indices;
485 }
486
487 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
488 Klass(id),
489 _nest_members(NULL),
490 _nest_host(NULL),
491 _permitted_subclasses(NULL),
492 _record_components(NULL),
493 _static_field_size(parser.static_field_size()),
494 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
495 _itable_len(parser.itable_size()),
496 _nest_host_index(0),
497 _init_state(allocated),
498 _reference_type(parser.reference_type()),
499 _init_thread(NULL)
500 {
501 set_vtable_length(parser.vtable_size());
502 set_kind(kind);
503 set_access_flags(parser.access_flags());
504 if (parser.is_hidden()) set_is_hidden();
505 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
506 false));
507
508 assert(NULL == _methods, "underlying memory not zeroed?");
509 assert(is_instance_klass(), "is layout incorrect?");
510 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
511 }
512
513 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
514 Array<Method*>* methods) {
515 if (methods != NULL && methods != Universe::the_empty_method_array() &&
516 !methods->is_shared()) {
517 for (int i = 0; i < methods->length(); i++) {
518 Method* method = methods->at(i);
519 if (method == NULL) continue; // maybe null if error processing
520 // Only want to delete methods that are not executing for RedefineClasses.
521 // The previous version will point to them so they're not totally dangling
522 assert (!method->on_stack(), "shouldn't be called with methods on stack");
523 MetadataFactory::free_metadata(loader_data, method);
524 }
525 MetadataFactory::free_array<Method*>(loader_data, methods);
526 }
527 }
528
529 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
530 const Klass* super_klass,
531 Array<InstanceKlass*>* local_interfaces,
532 Array<InstanceKlass*>* transitive_interfaces) {
533 // Only deallocate transitive interfaces if not empty, same as super class
534 // or same as local interfaces. See code in parseClassFile.
535 Array<InstanceKlass*>* ti = transitive_interfaces;
536 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
537 // check that the interfaces don't come from super class
538 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
539 InstanceKlass::cast(super_klass)->transitive_interfaces();
540 if (ti != sti && ti != NULL && !ti->is_shared()) {
541 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
542 }
543 }
544
545 // local interfaces can be empty
546 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
547 local_interfaces != NULL && !local_interfaces->is_shared()) {
548 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
549 }
550 }
551
552 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
553 Array<RecordComponent*>* record_components) {
554 if (record_components != NULL && !record_components->is_shared()) {
555 for (int i = 0; i < record_components->length(); i++) {
556 RecordComponent* record_component = record_components->at(i);
557 MetadataFactory::free_metadata(loader_data, record_component);
558 }
559 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
560 }
561 }
562
563 // This function deallocates the metadata and C heap pointers that the
564 // InstanceKlass points to.
565 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
566
567 // Orphan the mirror first, CMS thinks it's still live.
568 if (java_mirror() != NULL) {
569 java_lang_Class::set_klass(java_mirror(), NULL);
570 }
571
572 // Also remove mirror from handles
573 loader_data->remove_handle(_java_mirror);
574
575 // Need to take this class off the class loader data list.
576 loader_data->remove_class(this);
577
578 // The array_klass for this class is created later, after error handling.
579 // For class redefinition, we keep the original class so this scratch class
580 // doesn't have an array class. Either way, assert that there is nothing
581 // to deallocate.
582 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
583
584 // Release C heap allocated data that this points to, which includes
585 // reference counting symbol names.
586 release_C_heap_structures_internal();
587
588 deallocate_methods(loader_data, methods());
589 set_methods(NULL);
590
591 deallocate_record_components(loader_data, record_components());
592 set_record_components(NULL);
593
594 if (method_ordering() != NULL &&
595 method_ordering() != Universe::the_empty_int_array() &&
596 !method_ordering()->is_shared()) {
597 MetadataFactory::free_array<int>(loader_data, method_ordering());
598 }
599 set_method_ordering(NULL);
600
601 // default methods can be empty
602 if (default_methods() != NULL &&
603 default_methods() != Universe::the_empty_method_array() &&
604 !default_methods()->is_shared()) {
605 MetadataFactory::free_array<Method*>(loader_data, default_methods());
606 }
607 // Do NOT deallocate the default methods, they are owned by superinterfaces.
608 set_default_methods(NULL);
609
610 // default methods vtable indices can be empty
611 if (default_vtable_indices() != NULL &&
612 !default_vtable_indices()->is_shared()) {
613 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
614 }
615 set_default_vtable_indices(NULL);
616
617
618 // This array is in Klass, but remove it with the InstanceKlass since
619 // this place would be the only caller and it can share memory with transitive
620 // interfaces.
621 if (secondary_supers() != NULL &&
622 secondary_supers() != Universe::the_empty_klass_array() &&
623 // see comments in compute_secondary_supers about the following cast
624 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
625 !secondary_supers()->is_shared()) {
626 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
627 }
628 set_secondary_supers(NULL);
629
630 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
631 set_transitive_interfaces(NULL);
632 set_local_interfaces(NULL);
633
634 if (fields() != NULL && !fields()->is_shared()) {
635 MetadataFactory::free_array<jushort>(loader_data, fields());
636 }
637 set_fields(NULL, 0);
638
639 // If a method from a redefined class is using this constant pool, don't
640 // delete it, yet. The new class's previous version will point to this.
641 if (constants() != NULL) {
642 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
643 if (!constants()->is_shared()) {
644 MetadataFactory::free_metadata(loader_data, constants());
645 }
646 // Delete any cached resolution errors for the constant pool
647 SystemDictionary::delete_resolution_error(constants());
648
649 set_constants(NULL);
650 }
651
652 if (inner_classes() != NULL &&
653 inner_classes() != Universe::the_empty_short_array() &&
654 !inner_classes()->is_shared()) {
655 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
656 }
657 set_inner_classes(NULL);
658
659 if (nest_members() != NULL &&
660 nest_members() != Universe::the_empty_short_array() &&
661 !nest_members()->is_shared()) {
662 MetadataFactory::free_array<jushort>(loader_data, nest_members());
663 }
664 set_nest_members(NULL);
665
666 if (permitted_subclasses() != NULL &&
667 permitted_subclasses() != Universe::the_empty_short_array() &&
668 !permitted_subclasses()->is_shared()) {
669 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
670 }
671 set_permitted_subclasses(NULL);
672
673 // We should deallocate the Annotations instance if it's not in shared spaces.
674 if (annotations() != NULL && !annotations()->is_shared()) {
675 MetadataFactory::free_metadata(loader_data, annotations());
676 }
677 set_annotations(NULL);
678
679 SystemDictionaryShared::handle_class_unloading(this);
680 }
681
682 bool InstanceKlass::is_record() const {
683 return _record_components != NULL &&
684 is_final() &&
685 java_super() == vmClasses::Record_klass();
686 }
687
688 bool InstanceKlass::is_sealed() const {
689 return _permitted_subclasses != NULL &&
690 _permitted_subclasses != Universe::the_empty_short_array();
691 }
692
693 bool InstanceKlass::should_be_initialized() const {
694 return !is_initialized();
695 }
696
697 klassItable InstanceKlass::itable() const {
698 return klassItable(const_cast<InstanceKlass*>(this));
699 }
700
701 void InstanceKlass::eager_initialize(Thread *thread) {
702 if (!EagerInitialization) return;
703
704 if (this->is_not_initialized()) {
705 // abort if the the class has a class initializer
706 if (this->class_initializer() != NULL) return;
707
708 // abort if it is java.lang.Object (initialization is handled in genesis)
709 Klass* super_klass = super();
710 if (super_klass == NULL) return;
711
712 // abort if the super class should be initialized
713 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
714
715 // call body to expose the this pointer
716 eager_initialize_impl();
717 }
718 }
719
720 // JVMTI spec thinks there are signers and protection domain in the
721 // instanceKlass. These accessors pretend these fields are there.
722 // The hprof specification also thinks these fields are in InstanceKlass.
723 oop InstanceKlass::protection_domain() const {
724 // return the protection_domain from the mirror
725 return java_lang_Class::protection_domain(java_mirror());
726 }
727
728 // To remove these from requires an incompatible change and CCC request.
729 objArrayOop InstanceKlass::signers() const {
730 // return the signers from the mirror
731 return java_lang_Class::signers(java_mirror());
732 }
733
734 oop InstanceKlass::init_lock() const {
735 // return the init lock from the mirror
736 oop lock = java_lang_Class::init_lock(java_mirror());
737 // Prevent reordering with any access of initialization state
738 OrderAccess::loadload();
739 assert(lock != NULL || !is_not_initialized(), // initialized or in_error state
740 "only fully initialized state can have a null lock");
741 return lock;
742 }
743
744 // Set the initialization lock to null so the object can be GC'ed. Any racing
745 // threads to get this lock will see a null lock and will not lock.
746 // That's okay because they all check for initialized state after getting
747 // the lock and return.
748 void InstanceKlass::fence_and_clear_init_lock() {
749 // make sure previous stores are all done, notably the init_state.
750 OrderAccess::storestore();
751 java_lang_Class::clear_init_lock(java_mirror());
752 assert(!is_not_initialized(), "class must be initialized now");
753 }
754
755 void InstanceKlass::eager_initialize_impl() {
756 EXCEPTION_MARK;
757 HandleMark hm(THREAD);
758 Handle h_init_lock(THREAD, init_lock());
759 ObjectLocker ol(h_init_lock, THREAD);
760
761 // abort if someone beat us to the initialization
762 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
763
764 ClassState old_state = init_state();
765 link_class_impl(THREAD);
766 if (HAS_PENDING_EXCEPTION) {
767 CLEAR_PENDING_EXCEPTION;
768 // Abort if linking the class throws an exception.
769
770 // Use a test to avoid redundantly resetting the state if there's
771 // no change. Set_init_state() asserts that state changes make
772 // progress, whereas here we might just be spinning in place.
773 if (old_state != _init_state)
774 set_init_state(old_state);
775 } else {
776 // linking successfull, mark class as initialized
777 set_init_state(fully_initialized);
778 fence_and_clear_init_lock();
779 // trace
780 if (log_is_enabled(Info, class, init)) {
781 ResourceMark rm(THREAD);
782 log_info(class, init)("[Initialized %s without side effects]", external_name());
783 }
784 }
785 }
786
787
788 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
789 // process. The step comments refers to the procedure described in that section.
790 // Note: implementation moved to static method to expose the this pointer.
791 void InstanceKlass::initialize(TRAPS) {
792 if (this->should_be_initialized()) {
793 initialize_impl(CHECK);
794 // Note: at this point the class may be initialized
795 // OR it may be in the state of being initialized
796 // in case of recursive initialization!
797 } else {
798 assert(is_initialized(), "sanity check");
799 }
800 }
801
802
803 bool InstanceKlass::verify_code(TRAPS) {
804 // 1) Verify the bytecodes
805 return Verifier::verify(this, should_verify_class(), THREAD);
806 }
807
808 void InstanceKlass::link_class(TRAPS) {
809 assert(is_loaded(), "must be loaded");
810 if (!is_linked()) {
811 link_class_impl(CHECK);
812 }
813 }
814
815 // Called to verify that a class can link during initialization, without
816 // throwing a VerifyError.
817 bool InstanceKlass::link_class_or_fail(TRAPS) {
818 assert(is_loaded(), "must be loaded");
819 if (!is_linked()) {
820 link_class_impl(CHECK_false);
821 }
822 return is_linked();
823 }
824
825 bool InstanceKlass::link_class_impl(TRAPS) {
826 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
827 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
828 // the class has failed verification. Throwing the NoClassDefFoundError here is just
829 // a convenient way to stop repeat attempts to verify the same (bad) class.
830 //
831 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
832 // if we are executing Java code. This is not a problem for CDS dumping phase since
833 // it doesn't execute any Java code.
834 ResourceMark rm(THREAD);
835 Exceptions::fthrow(THREAD_AND_LOCATION,
836 vmSymbols::java_lang_NoClassDefFoundError(),
837 "Class %s, or one of its supertypes, failed class initialization",
838 external_name());
839 return false;
840 }
841 // return if already verified
842 if (is_linked()) {
843 return true;
844 }
845
846 // Timing
847 // timer handles recursion
848 JavaThread* jt = THREAD;
849
850 // link super class before linking this class
851 Klass* super_klass = super();
852 if (super_klass != NULL) {
853 if (super_klass->is_interface()) { // check if super class is an interface
854 ResourceMark rm(THREAD);
855 Exceptions::fthrow(
856 THREAD_AND_LOCATION,
857 vmSymbols::java_lang_IncompatibleClassChangeError(),
858 "class %s has interface %s as super class",
859 external_name(),
860 super_klass->external_name()
861 );
862 return false;
863 }
864
865 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
866 ik_super->link_class_impl(CHECK_false);
867 }
868
869 // link all interfaces implemented by this class before linking this class
870 Array<InstanceKlass*>* interfaces = local_interfaces();
871 int num_interfaces = interfaces->length();
872 for (int index = 0; index < num_interfaces; index++) {
873 InstanceKlass* interk = interfaces->at(index);
874 interk->link_class_impl(CHECK_false);
875 }
876
877 // in case the class is linked in the process of linking its superclasses
878 if (is_linked()) {
879 return true;
880 }
881
882 // trace only the link time for this klass that includes
883 // the verification time
884 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
885 ClassLoader::perf_class_link_selftime(),
886 ClassLoader::perf_classes_linked(),
887 jt->get_thread_stat()->perf_recursion_counts_addr(),
888 jt->get_thread_stat()->perf_timers_addr(),
889 PerfClassTraceTime::CLASS_LINK);
890
891 // verification & rewriting
892 {
893 HandleMark hm(THREAD);
894 Handle h_init_lock(THREAD, init_lock());
895 ObjectLocker ol(h_init_lock, jt);
896 // rewritten will have been set if loader constraint error found
897 // on an earlier link attempt
898 // don't verify or rewrite if already rewritten
899 //
900
901 if (!is_linked()) {
902 if (!is_rewritten()) {
903 if (is_shared()) {
904 assert(!verified_at_dump_time(), "must be");
905 }
906 {
907 bool verify_ok = verify_code(THREAD);
908 if (!verify_ok) {
909 return false;
910 }
911 }
912
913 // Just in case a side-effect of verify linked this class already
914 // (which can sometimes happen since the verifier loads classes
915 // using custom class loaders, which are free to initialize things)
916 if (is_linked()) {
917 return true;
918 }
919
920 // also sets rewritten
921 rewrite_class(CHECK_false);
922 } else if (is_shared()) {
923 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
924 }
925
926 // relocate jsrs and link methods after they are all rewritten
927 link_methods(CHECK_false);
928
929 // Initialize the vtable and interface table after
930 // methods have been rewritten since rewrite may
931 // fabricate new Method*s.
932 // also does loader constraint checking
933 //
934 // initialize_vtable and initialize_itable need to be rerun
935 // for a shared class if
936 // 1) the class is loaded by custom class loader or
937 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
938 // 3) the class was not verified during dump time
939 bool need_init_table = true;
940 if (is_shared() && verified_at_dump_time() &&
941 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
942 need_init_table = false;
943 }
944 if (need_init_table) {
945 vtable().initialize_vtable_and_check_constraints(CHECK_false);
946 itable().initialize_itable_and_check_constraints(CHECK_false);
947 }
948 #ifdef ASSERT
949 vtable().verify(tty, true);
950 // In case itable verification is ever added.
951 // itable().verify(tty, true);
952 #endif
953 if (UseVtableBasedCHA) {
954 MutexLocker ml(THREAD, Compile_lock);
955 set_init_state(linked);
956
957 // Now flush all code that assume the class is not linked.
958 if (Universe::is_fully_initialized()) {
959 CodeCache::flush_dependents_on(this);
960 }
961 } else {
962 set_init_state(linked);
963 }
964 if (JvmtiExport::should_post_class_prepare()) {
965 JvmtiExport::post_class_prepare(THREAD, this);
966 }
967 }
968 }
969 return true;
970 }
971
972 // Rewrite the byte codes of all of the methods of a class.
973 // The rewriter must be called exactly once. Rewriting must happen after
974 // verification but before the first method of the class is executed.
975 void InstanceKlass::rewrite_class(TRAPS) {
976 assert(is_loaded(), "must be loaded");
977 if (is_rewritten()) {
978 assert(is_shared(), "rewriting an unshared class?");
979 return;
980 }
981 Rewriter::rewrite(this, CHECK);
982 set_rewritten();
983 }
984
985 // Now relocate and link method entry points after class is rewritten.
986 // This is outside is_rewritten flag. In case of an exception, it can be
987 // executed more than once.
988 void InstanceKlass::link_methods(TRAPS) {
989 int len = methods()->length();
990 for (int i = len-1; i >= 0; i--) {
991 methodHandle m(THREAD, methods()->at(i));
992
993 // Set up method entry points for compiler and interpreter .
994 m->link_method(m, CHECK);
995 }
996 }
997
998 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
999 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1000 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1001 for (int i = 0; i < local_interfaces()->length(); ++i) {
1002 InstanceKlass* ik = local_interfaces()->at(i);
1003
1004 // Initialization is depth first search ie. we start with top of the inheritance tree
1005 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1006 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1007 if (ik->has_nonstatic_concrete_methods()) {
1008 ik->initialize_super_interfaces(CHECK);
1009 }
1010
1011 // Only initialize() interfaces that "declare" concrete methods.
1012 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1013 ik->initialize(CHECK);
1014 }
1015 }
1016 }
1017
1018 ResourceHashtable<const InstanceKlass*, OopHandle, 107, ResourceObj::C_HEAP, mtClass>
1019 _initialization_error_table;
1020
1021 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1022 // Create the same exception with a message indicating the thread name,
1023 // and the StackTraceElements.
1024 // If the initialization error is OOM, this might not work, but if GC kicks in
1025 // this would be still be helpful.
1026 JavaThread* THREAD = current;
1027 Handle cause = java_lang_Throwable::get_cause_with_stack_trace(exception, THREAD);
1028 if (HAS_PENDING_EXCEPTION || cause.is_null()) {
1029 CLEAR_PENDING_EXCEPTION;
1030 return;
1031 }
1032
1033 MutexLocker ml(THREAD, ClassInitError_lock);
1034 OopHandle elem = OopHandle(Universe::vm_global(), cause());
1035 bool created = false;
1036 _initialization_error_table.put_if_absent(this, elem, &created);
1037 assert(created, "Initialization is single threaded");
1038 ResourceMark rm(THREAD);
1039 log_trace(class, init)("Initialization error added for class %s", external_name());
1040 }
1041
1042 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1043 MutexLocker ml(current, ClassInitError_lock);
1044 OopHandle* h = _initialization_error_table.get(this);
1045 return (h != nullptr) ? h->resolve() : nullptr;
1046 }
1047
1048 // Need to remove entries for unloaded classes.
1049 void InstanceKlass::clean_initialization_error_table() {
1050 struct InitErrorTableCleaner {
1051 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1052 if (!ik->is_loader_alive()) {
1053 h.release(Universe::vm_global());
1054 return true;
1055 } else {
1056 return false;
1057 }
1058 }
1059 };
1060
1061 MutexLocker ml(ClassInitError_lock);
1062 InitErrorTableCleaner cleaner;
1063 _initialization_error_table.unlink(&cleaner);
1064 }
1065
1066 void InstanceKlass::initialize_impl(TRAPS) {
1067 HandleMark hm(THREAD);
1068
1069 // Make sure klass is linked (verified) before initialization
1070 // A class could already be verified, since it has been reflected upon.
1071 link_class(CHECK);
1072
1073 DTRACE_CLASSINIT_PROBE(required, -1);
1074
1075 bool wait = false;
1076
1077 JavaThread* jt = THREAD;
1078
1079 // refer to the JVM book page 47 for description of steps
1080 // Step 1
1081 {
1082 Handle h_init_lock(THREAD, init_lock());
1083 ObjectLocker ol(h_init_lock, jt);
1084
1085 // Step 2
1086 // If we were to use wait() instead of waitInterruptibly() then
1087 // we might end up throwing IE from link/symbol resolution sites
1088 // that aren't expected to throw. This would wreak havoc. See 6320309.
1089 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1090 wait = true;
1091 jt->set_class_to_be_initialized(this);
1092 ol.wait_uninterruptibly(jt);
1093 jt->set_class_to_be_initialized(NULL);
1094 }
1095
1096 // Step 3
1097 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1098 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1099 return;
1100 }
1101
1102 // Step 4
1103 if (is_initialized()) {
1104 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1105 return;
1106 }
1107
1108 // Step 5
1109 if (is_in_error_state()) {
1110 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1111 ResourceMark rm(THREAD);
1112 Handle cause(THREAD, get_initialization_error(THREAD));
1113
1114 stringStream ss;
1115 ss.print("Could not initialize class %s", external_name());
1116 if (cause.is_null()) {
1117 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1118 } else {
1119 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1120 ss.as_string(), cause);
1121 }
1122 }
1123
1124 // Step 6
1125 set_init_state(being_initialized);
1126 set_init_thread(jt);
1127 }
1128
1129 // Step 7
1130 // Next, if C is a class rather than an interface, initialize it's super class and super
1131 // interfaces.
1132 if (!is_interface()) {
1133 Klass* super_klass = super();
1134 if (super_klass != NULL && super_klass->should_be_initialized()) {
1135 super_klass->initialize(THREAD);
1136 }
1137 // If C implements any interface that declares a non-static, concrete method,
1138 // the initialization of C triggers initialization of its super interfaces.
1139 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1140 // having a superinterface that declares, non-static, concrete methods
1141 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1142 initialize_super_interfaces(THREAD);
1143 }
1144
1145 // If any exceptions, complete abruptly, throwing the same exception as above.
1146 if (HAS_PENDING_EXCEPTION) {
1147 Handle e(THREAD, PENDING_EXCEPTION);
1148 CLEAR_PENDING_EXCEPTION;
1149 {
1150 EXCEPTION_MARK;
1151 add_initialization_error(THREAD, e);
1152 // Locks object, set state, and notify all waiting threads
1153 set_initialization_state_and_notify(initialization_error, THREAD);
1154 CLEAR_PENDING_EXCEPTION;
1155 }
1156 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1157 THROW_OOP(e());
1158 }
1159 }
1160
1161
1162 // Step 8
1163 {
1164 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1165 if (class_initializer() != NULL) {
1166 // Timer includes any side effects of class initialization (resolution,
1167 // etc), but not recursive entry into call_class_initializer().
1168 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1169 ClassLoader::perf_class_init_selftime(),
1170 ClassLoader::perf_classes_inited(),
1171 jt->get_thread_stat()->perf_recursion_counts_addr(),
1172 jt->get_thread_stat()->perf_timers_addr(),
1173 PerfClassTraceTime::CLASS_CLINIT);
1174 call_class_initializer(THREAD);
1175 } else {
1176 // The elapsed time is so small it's not worth counting.
1177 if (UsePerfData) {
1178 ClassLoader::perf_classes_inited()->inc();
1179 }
1180 call_class_initializer(THREAD);
1181 }
1182 }
1183
1184 // Step 9
1185 if (!HAS_PENDING_EXCEPTION) {
1186 set_initialization_state_and_notify(fully_initialized, CHECK);
1187 debug_only(vtable().verify(tty, true);)
1188 }
1189 else {
1190 // Step 10 and 11
1191 Handle e(THREAD, PENDING_EXCEPTION);
1192 CLEAR_PENDING_EXCEPTION;
1193 // JVMTI has already reported the pending exception
1194 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1195 JvmtiExport::clear_detected_exception(jt);
1196 {
1197 EXCEPTION_MARK;
1198 add_initialization_error(THREAD, e);
1199 set_initialization_state_and_notify(initialization_error, THREAD);
1200 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1201 // JVMTI has already reported the pending exception
1202 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1203 JvmtiExport::clear_detected_exception(jt);
1204 }
1205 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1206 if (e->is_a(vmClasses::Error_klass())) {
1207 THROW_OOP(e());
1208 } else {
1209 JavaCallArguments args(e);
1210 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1211 vmSymbols::throwable_void_signature(),
1212 &args);
1213 }
1214 }
1215 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1216 }
1217
1218
1219 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1220 Handle h_init_lock(THREAD, init_lock());
1221 if (h_init_lock() != NULL) {
1222 ObjectLocker ol(h_init_lock, THREAD);
1223 set_init_thread(NULL); // reset _init_thread before changing _init_state
1224 set_init_state(state);
1225 fence_and_clear_init_lock();
1226 ol.notify_all(CHECK);
1227 } else {
1228 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1229 set_init_thread(NULL); // reset _init_thread before changing _init_state
1230 set_init_state(state);
1231 }
1232 }
1233
1234 InstanceKlass* InstanceKlass::implementor() const {
1235 InstanceKlass* volatile* ik = adr_implementor();
1236 if (ik == NULL) {
1237 return NULL;
1238 } else {
1239 // This load races with inserts, and therefore needs acquire.
1240 InstanceKlass* ikls = Atomic::load_acquire(ik);
1241 if (ikls != NULL && !ikls->is_loader_alive()) {
1242 return NULL; // don't return unloaded class
1243 } else {
1244 return ikls;
1245 }
1246 }
1247 }
1248
1249
1250 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1251 assert_locked_or_safepoint(Compile_lock);
1252 assert(is_interface(), "not interface");
1253 InstanceKlass* volatile* addr = adr_implementor();
1254 assert(addr != NULL, "null addr");
1255 if (addr != NULL) {
1256 Atomic::release_store(addr, ik);
1257 }
1258 }
1259
1260 int InstanceKlass::nof_implementors() const {
1261 InstanceKlass* ik = implementor();
1262 if (ik == NULL) {
1263 return 0;
1264 } else if (ik != this) {
1265 return 1;
1266 } else {
1267 return 2;
1268 }
1269 }
1270
1271 // The embedded _implementor field can only record one implementor.
1272 // When there are more than one implementors, the _implementor field
1273 // is set to the interface Klass* itself. Following are the possible
1274 // values for the _implementor field:
1275 // NULL - no implementor
1276 // implementor Klass* - one implementor
1277 // self - more than one implementor
1278 //
1279 // The _implementor field only exists for interfaces.
1280 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1281 if (Universe::is_fully_initialized()) {
1282 assert_lock_strong(Compile_lock);
1283 }
1284 assert(is_interface(), "not interface");
1285 // Filter out my subinterfaces.
1286 // (Note: Interfaces are never on the subklass list.)
1287 if (ik->is_interface()) return;
1288
1289 // Filter out subclasses whose supers already implement me.
1290 // (Note: CHA must walk subclasses of direct implementors
1291 // in order to locate indirect implementors.)
1292 InstanceKlass* super_ik = ik->java_super();
1293 if (super_ik != NULL && super_ik->implements_interface(this))
1294 // We only need to check one immediate superclass, since the
1295 // implements_interface query looks at transitive_interfaces.
1296 // Any supers of the super have the same (or fewer) transitive_interfaces.
1297 return;
1298
1299 InstanceKlass* iklass = implementor();
1300 if (iklass == NULL) {
1301 set_implementor(ik);
1302 } else if (iklass != this && iklass != ik) {
1303 // There is already an implementor. Use itself as an indicator of
1304 // more than one implementors.
1305 set_implementor(this);
1306 }
1307
1308 // The implementor also implements the transitive_interfaces
1309 for (int index = 0; index < local_interfaces()->length(); index++) {
1310 local_interfaces()->at(index)->add_implementor(ik);
1311 }
1312 }
1313
1314 void InstanceKlass::init_implementor() {
1315 if (is_interface()) {
1316 set_implementor(NULL);
1317 }
1318 }
1319
1320
1321 void InstanceKlass::process_interfaces() {
1322 // link this class into the implementors list of every interface it implements
1323 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1324 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1325 InstanceKlass* interf = local_interfaces()->at(i);
1326 assert(interf->is_interface(), "expected interface");
1327 interf->add_implementor(this);
1328 }
1329 }
1330
1331 bool InstanceKlass::can_be_primary_super_slow() const {
1332 if (is_interface())
1333 return false;
1334 else
1335 return Klass::can_be_primary_super_slow();
1336 }
1337
1338 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1339 Array<InstanceKlass*>* transitive_interfaces) {
1340 // The secondaries are the implemented interfaces.
1341 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1342 int num_secondaries = num_extra_slots + interfaces->length();
1343 if (num_secondaries == 0) {
1344 // Must share this for correct bootstrapping!
1345 set_secondary_supers(Universe::the_empty_klass_array());
1346 return NULL;
1347 } else if (num_extra_slots == 0) {
1348 // The secondary super list is exactly the same as the transitive interfaces, so
1349 // let's use it instead of making a copy.
1350 // Redefine classes has to be careful not to delete this!
1351 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1352 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1353 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1354 return NULL;
1355 } else {
1356 // Copy transitive interfaces to a temporary growable array to be constructed
1357 // into the secondary super list with extra slots.
1358 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1359 for (int i = 0; i < interfaces->length(); i++) {
1360 secondaries->push(interfaces->at(i));
1361 }
1362 return secondaries;
1363 }
1364 }
1365
1366 bool InstanceKlass::implements_interface(Klass* k) const {
1367 if (this == k) return true;
1368 assert(k->is_interface(), "should be an interface class");
1369 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1370 if (transitive_interfaces()->at(i) == k) {
1371 return true;
1372 }
1373 }
1374 return false;
1375 }
1376
1377 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1378 // Verify direct super interface
1379 if (this == k) return true;
1380 assert(k->is_interface(), "should be an interface class");
1381 for (int i = 0; i < local_interfaces()->length(); i++) {
1382 if (local_interfaces()->at(i) == k) {
1383 return true;
1384 }
1385 }
1386 return false;
1387 }
1388
1389 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1390 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1391 int size = objArrayOopDesc::object_size(length);
1392 Klass* ak = array_klass(n, CHECK_NULL);
1393 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1394 /* do_zero */ true, CHECK_NULL);
1395 return o;
1396 }
1397
1398 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1399 if (TraceFinalizerRegistration) {
1400 tty->print("Registered ");
1401 i->print_value_on(tty);
1402 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1403 }
1404 instanceHandle h_i(THREAD, i);
1405 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1406 JavaValue result(T_VOID);
1407 JavaCallArguments args(h_i);
1408 methodHandle mh (THREAD, Universe::finalizer_register_method());
1409 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1410 return h_i();
1411 }
1412
1413 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1414 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1415 int size = size_helper(); // Query before forming handle.
1416
1417 instanceOop i;
1418
1419 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1420 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1421 i = register_finalizer(i, CHECK_NULL);
1422 }
1423 return i;
1424 }
1425
1426 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1427 return instanceHandle(THREAD, allocate_instance(THREAD));
1428 }
1429
1430 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1431 if (is_interface() || is_abstract()) {
1432 ResourceMark rm(THREAD);
1433 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1434 : vmSymbols::java_lang_InstantiationException(), external_name());
1435 }
1436 if (this == vmClasses::Class_klass()) {
1437 ResourceMark rm(THREAD);
1438 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1439 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1440 }
1441 }
1442
1443 Klass* InstanceKlass::array_klass(int n, TRAPS) {
1444 // Need load-acquire for lock-free read
1445 if (array_klasses_acquire() == NULL) {
1446 ResourceMark rm(THREAD);
1447 JavaThread *jt = THREAD;
1448 {
1449 // Atomic creation of array_klasses
1450 MutexLocker ma(THREAD, MultiArray_lock);
1451
1452 // Check if update has already taken place
1453 if (array_klasses() == NULL) {
1454 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1455 // use 'release' to pair with lock-free load
1456 release_set_array_klasses(k);
1457 }
1458 }
1459 }
1460 // array_klasses() will always be set at this point
1461 ObjArrayKlass* oak = array_klasses();
1462 return oak->array_klass(n, THREAD);
1463 }
1464
1465 Klass* InstanceKlass::array_klass_or_null(int n) {
1466 // Need load-acquire for lock-free read
1467 ObjArrayKlass* oak = array_klasses_acquire();
1468 if (oak == NULL) {
1469 return NULL;
1470 } else {
1471 return oak->array_klass_or_null(n);
1472 }
1473 }
1474
1475 Klass* InstanceKlass::array_klass(TRAPS) {
1476 return array_klass(1, THREAD);
1477 }
1478
1479 Klass* InstanceKlass::array_klass_or_null() {
1480 return array_klass_or_null(1);
1481 }
1482
1483 static int call_class_initializer_counter = 0; // for debugging
1484
1485 Method* InstanceKlass::class_initializer() const {
1486 Method* clinit = find_method(
1487 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1488 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1489 return clinit;
1490 }
1491 return NULL;
1492 }
1493
1494 void InstanceKlass::call_class_initializer(TRAPS) {
1495 if (ReplayCompiles &&
1496 (ReplaySuppressInitializers == 1 ||
1497 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1498 // Hide the existence of the initializer for the purpose of replaying the compile
1499 return;
1500 }
1501
1502 methodHandle h_method(THREAD, class_initializer());
1503 assert(!is_initialized(), "we cannot initialize twice");
1504 LogTarget(Info, class, init) lt;
1505 if (lt.is_enabled()) {
1506 ResourceMark rm(THREAD);
1507 LogStream ls(lt);
1508 ls.print("%d Initializing ", call_class_initializer_counter++);
1509 name()->print_value_on(&ls);
1510 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1511 }
1512 if (h_method() != NULL) {
1513 JavaCallArguments args; // No arguments
1514 JavaValue result(T_VOID);
1515 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1516 }
1517 }
1518
1519
1520 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1521 InterpreterOopMap* entry_for) {
1522 // Lazily create the _oop_map_cache at first request
1523 // Lock-free access requires load_acquire.
1524 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1525 if (oop_map_cache == NULL) {
1526 MutexLocker x(OopMapCacheAlloc_lock);
1527 // Check if _oop_map_cache was allocated while we were waiting for this lock
1528 if ((oop_map_cache = _oop_map_cache) == NULL) {
1529 oop_map_cache = new OopMapCache();
1530 // Ensure _oop_map_cache is stable, since it is examined without a lock
1531 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1532 }
1533 }
1534 // _oop_map_cache is constant after init; lookup below does its own locking.
1535 oop_map_cache->lookup(method, bci, entry_for);
1536 }
1537
1538 bool InstanceKlass::contains_field_offset(int offset) {
1539 fieldDescriptor fd;
1540 return find_field_from_offset(offset, false, &fd);
1541 }
1542
1543 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1544 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1545 Symbol* f_name = fs.name();
1546 Symbol* f_sig = fs.signature();
1547 if (f_name == name && f_sig == sig) {
1548 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1549 return true;
1550 }
1551 }
1552 return false;
1553 }
1554
1555
1556 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1557 const int n = local_interfaces()->length();
1558 for (int i = 0; i < n; i++) {
1559 Klass* intf1 = local_interfaces()->at(i);
1560 assert(intf1->is_interface(), "just checking type");
1561 // search for field in current interface
1562 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1563 assert(fd->is_static(), "interface field must be static");
1564 return intf1;
1565 }
1566 // search for field in direct superinterfaces
1567 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1568 if (intf2 != NULL) return intf2;
1569 }
1570 // otherwise field lookup fails
1571 return NULL;
1572 }
1573
1574
1575 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1576 // search order according to newest JVM spec (5.4.3.2, p.167).
1577 // 1) search for field in current klass
1578 if (find_local_field(name, sig, fd)) {
1579 return const_cast<InstanceKlass*>(this);
1580 }
1581 // 2) search for field recursively in direct superinterfaces
1582 { Klass* intf = find_interface_field(name, sig, fd);
1583 if (intf != NULL) return intf;
1584 }
1585 // 3) apply field lookup recursively if superclass exists
1586 { Klass* supr = super();
1587 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1588 }
1589 // 4) otherwise field lookup fails
1590 return NULL;
1591 }
1592
1593
1594 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1595 // search order according to newest JVM spec (5.4.3.2, p.167).
1596 // 1) search for field in current klass
1597 if (find_local_field(name, sig, fd)) {
1598 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1599 }
1600 // 2) search for field recursively in direct superinterfaces
1601 if (is_static) {
1602 Klass* intf = find_interface_field(name, sig, fd);
1603 if (intf != NULL) return intf;
1604 }
1605 // 3) apply field lookup recursively if superclass exists
1606 { Klass* supr = super();
1607 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1608 }
1609 // 4) otherwise field lookup fails
1610 return NULL;
1611 }
1612
1613
1614 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1615 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1616 if (fs.offset() == offset) {
1617 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1618 if (fd->is_static() == is_static) return true;
1619 }
1620 }
1621 return false;
1622 }
1623
1624
1625 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1626 Klass* klass = const_cast<InstanceKlass*>(this);
1627 while (klass != NULL) {
1628 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1629 return true;
1630 }
1631 klass = klass->super();
1632 }
1633 return false;
1634 }
1635
1636
1637 void InstanceKlass::methods_do(void f(Method* method)) {
1638 // Methods aren't stable until they are loaded. This can be read outside
1639 // a lock through the ClassLoaderData for profiling
1640 if (!is_loaded()) {
1641 return;
1642 }
1643
1644 int len = methods()->length();
1645 for (int index = 0; index < len; index++) {
1646 Method* m = methods()->at(index);
1647 assert(m->is_method(), "must be method");
1648 f(m);
1649 }
1650 }
1651
1652
1653 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1654 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1655 if (fs.access_flags().is_static()) {
1656 fieldDescriptor& fd = fs.field_descriptor();
1657 cl->do_field(&fd);
1658 }
1659 }
1660 }
1661
1662
1663 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1664 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1665 if (fs.access_flags().is_static()) {
1666 fieldDescriptor& fd = fs.field_descriptor();
1667 f(&fd, mirror, CHECK);
1668 }
1669 }
1670 }
1671
1672 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1673 InstanceKlass* super = superklass();
1674 if (super != NULL) {
1675 super->do_nonstatic_fields(cl);
1676 }
1677 fieldDescriptor fd;
1678 int length = java_fields_count();
1679 for (int i = 0; i < length; i += 1) {
1680 fd.reinitialize(this, i);
1681 if (!fd.is_static()) {
1682 cl->do_field(&fd);
1683 }
1684 }
1685 }
1686
1687 // first in Pair is offset, second is index.
1688 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1689 return a->first - b->first;
1690 }
1691
1692 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1693 InstanceKlass* super = superklass();
1694 if (super != NULL) {
1695 super->print_nonstatic_fields(cl);
1696 }
1697 ResourceMark rm;
1698 fieldDescriptor fd;
1699 // In DebugInfo nonstatic fields are sorted by offset.
1700 GrowableArray<Pair<int,int> > fields_sorted;
1701 int i = 0;
1702 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1703 if (!fs.access_flags().is_static()) {
1704 fd = fs.field_descriptor();
1705 Pair<int,int> f(fs.offset(), fs.index());
1706 fields_sorted.push(f);
1707 i++;
1708 }
1709 }
1710 if (i > 0) {
1711 int length = i;
1712 assert(length == fields_sorted.length(), "duh");
1713 // _sort_Fn is defined in growableArray.hpp.
1714 fields_sorted.sort(compare_fields_by_offset);
1715 for (int i = 0; i < length; i++) {
1716 fd.reinitialize(this, fields_sorted.at(i).second);
1717 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1718 cl->do_field(&fd);
1719 }
1720 }
1721 }
1722
1723 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1724 if (array_klasses() != NULL)
1725 array_klasses()->array_klasses_do(f, THREAD);
1726 }
1727
1728 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1729 if (array_klasses() != NULL)
1730 array_klasses()->array_klasses_do(f);
1731 }
1732
1733 #ifdef ASSERT
1734 static int linear_search(const Array<Method*>* methods,
1735 const Symbol* name,
1736 const Symbol* signature) {
1737 const int len = methods->length();
1738 for (int index = 0; index < len; index++) {
1739 const Method* const m = methods->at(index);
1740 assert(m->is_method(), "must be method");
1741 if (m->signature() == signature && m->name() == name) {
1742 return index;
1743 }
1744 }
1745 return -1;
1746 }
1747 #endif
1748
1749 bool InstanceKlass::_disable_method_binary_search = false;
1750
1751 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1752 int len = methods->length();
1753 int l = 0;
1754 int h = len - 1;
1755 while (l <= h) {
1756 Method* m = methods->at(l);
1757 if (m->name() == name) {
1758 return l;
1759 }
1760 l++;
1761 }
1762 return -1;
1763 }
1764
1765 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1766 if (_disable_method_binary_search) {
1767 assert(DynamicDumpSharedSpaces, "must be");
1768 // At the final stage of dynamic dumping, the methods array may not be sorted
1769 // by ascending addresses of their names, so we can't use binary search anymore.
1770 // However, methods with the same name are still laid out consecutively inside the
1771 // methods array, so let's look for the first one that matches.
1772 return linear_search(methods, name);
1773 }
1774
1775 int len = methods->length();
1776 int l = 0;
1777 int h = len - 1;
1778
1779 // methods are sorted by ascending addresses of their names, so do binary search
1780 while (l <= h) {
1781 int mid = (l + h) >> 1;
1782 Method* m = methods->at(mid);
1783 assert(m->is_method(), "must be method");
1784 int res = m->name()->fast_compare(name);
1785 if (res == 0) {
1786 return mid;
1787 } else if (res < 0) {
1788 l = mid + 1;
1789 } else {
1790 h = mid - 1;
1791 }
1792 }
1793 return -1;
1794 }
1795
1796 // find_method looks up the name/signature in the local methods array
1797 Method* InstanceKlass::find_method(const Symbol* name,
1798 const Symbol* signature) const {
1799 return find_method_impl(name, signature,
1800 OverpassLookupMode::find,
1801 StaticLookupMode::find,
1802 PrivateLookupMode::find);
1803 }
1804
1805 Method* InstanceKlass::find_method_impl(const Symbol* name,
1806 const Symbol* signature,
1807 OverpassLookupMode overpass_mode,
1808 StaticLookupMode static_mode,
1809 PrivateLookupMode private_mode) const {
1810 return InstanceKlass::find_method_impl(methods(),
1811 name,
1812 signature,
1813 overpass_mode,
1814 static_mode,
1815 private_mode);
1816 }
1817
1818 // find_instance_method looks up the name/signature in the local methods array
1819 // and skips over static methods
1820 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1821 const Symbol* name,
1822 const Symbol* signature,
1823 PrivateLookupMode private_mode) {
1824 Method* const meth = InstanceKlass::find_method_impl(methods,
1825 name,
1826 signature,
1827 OverpassLookupMode::find,
1828 StaticLookupMode::skip,
1829 private_mode);
1830 assert(((meth == NULL) || !meth->is_static()),
1831 "find_instance_method should have skipped statics");
1832 return meth;
1833 }
1834
1835 // find_instance_method looks up the name/signature in the local methods array
1836 // and skips over static methods
1837 Method* InstanceKlass::find_instance_method(const Symbol* name,
1838 const Symbol* signature,
1839 PrivateLookupMode private_mode) const {
1840 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1841 }
1842
1843 // Find looks up the name/signature in the local methods array
1844 // and filters on the overpass, static and private flags
1845 // This returns the first one found
1846 // note that the local methods array can have up to one overpass, one static
1847 // and one instance (private or not) with the same name/signature
1848 Method* InstanceKlass::find_local_method(const Symbol* name,
1849 const Symbol* signature,
1850 OverpassLookupMode overpass_mode,
1851 StaticLookupMode static_mode,
1852 PrivateLookupMode private_mode) const {
1853 return InstanceKlass::find_method_impl(methods(),
1854 name,
1855 signature,
1856 overpass_mode,
1857 static_mode,
1858 private_mode);
1859 }
1860
1861 // Find looks up the name/signature in the local methods array
1862 // and filters on the overpass, static and private flags
1863 // This returns the first one found
1864 // note that the local methods array can have up to one overpass, one static
1865 // and one instance (private or not) with the same name/signature
1866 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1867 const Symbol* name,
1868 const Symbol* signature,
1869 OverpassLookupMode overpass_mode,
1870 StaticLookupMode static_mode,
1871 PrivateLookupMode private_mode) {
1872 return InstanceKlass::find_method_impl(methods,
1873 name,
1874 signature,
1875 overpass_mode,
1876 static_mode,
1877 private_mode);
1878 }
1879
1880 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1881 const Symbol* name,
1882 const Symbol* signature) {
1883 return InstanceKlass::find_method_impl(methods,
1884 name,
1885 signature,
1886 OverpassLookupMode::find,
1887 StaticLookupMode::find,
1888 PrivateLookupMode::find);
1889 }
1890
1891 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1892 const Symbol* name,
1893 const Symbol* signature,
1894 OverpassLookupMode overpass_mode,
1895 StaticLookupMode static_mode,
1896 PrivateLookupMode private_mode) {
1897 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1898 return hit >= 0 ? methods->at(hit): NULL;
1899 }
1900
1901 // true if method matches signature and conforms to skipping_X conditions.
1902 static bool method_matches(const Method* m,
1903 const Symbol* signature,
1904 bool skipping_overpass,
1905 bool skipping_static,
1906 bool skipping_private) {
1907 return ((m->signature() == signature) &&
1908 (!skipping_overpass || !m->is_overpass()) &&
1909 (!skipping_static || !m->is_static()) &&
1910 (!skipping_private || !m->is_private()));
1911 }
1912
1913 // Used directly for default_methods to find the index into the
1914 // default_vtable_indices, and indirectly by find_method
1915 // find_method_index looks in the local methods array to return the index
1916 // of the matching name/signature. If, overpass methods are being ignored,
1917 // the search continues to find a potential non-overpass match. This capability
1918 // is important during method resolution to prefer a static method, for example,
1919 // over an overpass method.
1920 // There is the possibility in any _method's array to have the same name/signature
1921 // for a static method, an overpass method and a local instance method
1922 // To correctly catch a given method, the search criteria may need
1923 // to explicitly skip the other two. For local instance methods, it
1924 // is often necessary to skip private methods
1925 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1926 const Symbol* name,
1927 const Symbol* signature,
1928 OverpassLookupMode overpass_mode,
1929 StaticLookupMode static_mode,
1930 PrivateLookupMode private_mode) {
1931 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
1932 const bool skipping_static = (static_mode == StaticLookupMode::skip);
1933 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
1934 const int hit = quick_search(methods, name);
1935 if (hit != -1) {
1936 const Method* const m = methods->at(hit);
1937
1938 // Do linear search to find matching signature. First, quick check
1939 // for common case, ignoring overpasses if requested.
1940 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1941 return hit;
1942 }
1943
1944 // search downwards through overloaded methods
1945 int i;
1946 for (i = hit - 1; i >= 0; --i) {
1947 const Method* const m = methods->at(i);
1948 assert(m->is_method(), "must be method");
1949 if (m->name() != name) {
1950 break;
1951 }
1952 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1953 return i;
1954 }
1955 }
1956 // search upwards
1957 for (i = hit + 1; i < methods->length(); ++i) {
1958 const Method* const m = methods->at(i);
1959 assert(m->is_method(), "must be method");
1960 if (m->name() != name) {
1961 break;
1962 }
1963 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1964 return i;
1965 }
1966 }
1967 // not found
1968 #ifdef ASSERT
1969 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1970 linear_search(methods, name, signature);
1971 assert(-1 == index, "binary search should have found entry %d", index);
1972 #endif
1973 }
1974 return -1;
1975 }
1976
1977 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1978 return find_method_by_name(methods(), name, end);
1979 }
1980
1981 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1982 const Symbol* name,
1983 int* end_ptr) {
1984 assert(end_ptr != NULL, "just checking");
1985 int start = quick_search(methods, name);
1986 int end = start + 1;
1987 if (start != -1) {
1988 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1989 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1990 *end_ptr = end;
1991 return start;
1992 }
1993 return -1;
1994 }
1995
1996 // uncached_lookup_method searches both the local class methods array and all
1997 // superclasses methods arrays, skipping any overpass methods in superclasses,
1998 // and possibly skipping private methods.
1999 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2000 const Symbol* signature,
2001 OverpassLookupMode overpass_mode,
2002 PrivateLookupMode private_mode) const {
2003 OverpassLookupMode overpass_local_mode = overpass_mode;
2004 const Klass* klass = this;
2005 while (klass != NULL) {
2006 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2007 signature,
2008 overpass_local_mode,
2009 StaticLookupMode::find,
2010 private_mode);
2011 if (method != NULL) {
2012 return method;
2013 }
2014 klass = klass->super();
2015 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2016 }
2017 return NULL;
2018 }
2019
2020 #ifdef ASSERT
2021 // search through class hierarchy and return true if this class or
2022 // one of the superclasses was redefined
2023 bool InstanceKlass::has_redefined_this_or_super() const {
2024 const Klass* klass = this;
2025 while (klass != NULL) {
2026 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2027 return true;
2028 }
2029 klass = klass->super();
2030 }
2031 return false;
2032 }
2033 #endif
2034
2035 // lookup a method in the default methods list then in all transitive interfaces
2036 // Do NOT return private or static methods
2037 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2038 Symbol* signature) const {
2039 Method* m = NULL;
2040 if (default_methods() != NULL) {
2041 m = find_method(default_methods(), name, signature);
2042 }
2043 // Look up interfaces
2044 if (m == NULL) {
2045 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2046 }
2047 return m;
2048 }
2049
2050 // lookup a method in all the interfaces that this class implements
2051 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2052 // They should only be found in the initial InterfaceMethodRef
2053 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2054 Symbol* signature,
2055 DefaultsLookupMode defaults_mode) const {
2056 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2057 int num_ifs = all_ifs->length();
2058 InstanceKlass *ik = NULL;
2059 for (int i = 0; i < num_ifs; i++) {
2060 ik = all_ifs->at(i);
2061 Method* m = ik->lookup_method(name, signature);
2062 if (m != NULL && m->is_public() && !m->is_static() &&
2063 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2064 return m;
2065 }
2066 }
2067 return NULL;
2068 }
2069
2070 /* jni_id_for_impl for jfieldIds only */
2071 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
2072 MutexLocker ml(JfieldIdCreation_lock);
2073 // Retry lookup after we got the lock
2074 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
2075 if (probe == NULL) {
2076 // Slow case, allocate new static field identifier
2077 probe = new JNIid(this, offset, jni_ids());
2078 set_jni_ids(probe);
2079 }
2080 return probe;
2081 }
2082
2083
2084 /* jni_id_for for jfieldIds only */
2085 JNIid* InstanceKlass::jni_id_for(int offset) {
2086 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
2087 if (probe == NULL) {
2088 probe = jni_id_for_impl(offset);
2089 }
2090 return probe;
2091 }
2092
2093 u2 InstanceKlass::enclosing_method_data(int offset) const {
2094 const Array<jushort>* const inner_class_list = inner_classes();
2095 if (inner_class_list == NULL) {
2096 return 0;
2097 }
2098 const int length = inner_class_list->length();
2099 if (length % inner_class_next_offset == 0) {
2100 return 0;
2101 }
2102 const int index = length - enclosing_method_attribute_size;
2103 assert(offset < enclosing_method_attribute_size, "invalid offset");
2104 return inner_class_list->at(index + offset);
2105 }
2106
2107 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2108 u2 method_index) {
2109 Array<jushort>* inner_class_list = inner_classes();
2110 assert (inner_class_list != NULL, "_inner_classes list is not set up");
2111 int length = inner_class_list->length();
2112 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2113 int index = length - enclosing_method_attribute_size;
2114 inner_class_list->at_put(
2115 index + enclosing_method_class_index_offset, class_index);
2116 inner_class_list->at_put(
2117 index + enclosing_method_method_index_offset, method_index);
2118 }
2119 }
2120
2121 // Lookup or create a jmethodID.
2122 // This code is called by the VMThread and JavaThreads so the
2123 // locking has to be done very carefully to avoid deadlocks
2124 // and/or other cache consistency problems.
2125 //
2126 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2127 size_t idnum = (size_t)method_h->method_idnum();
2128 jmethodID* jmeths = methods_jmethod_ids_acquire();
2129 size_t length = 0;
2130 jmethodID id = NULL;
2131
2132 // We use a double-check locking idiom here because this cache is
2133 // performance sensitive. In the normal system, this cache only
2134 // transitions from NULL to non-NULL which is safe because we use
2135 // release_set_methods_jmethod_ids() to advertise the new cache.
2136 // A partially constructed cache should never be seen by a racing
2137 // thread. We also use release_store() to save a new jmethodID
2138 // in the cache so a partially constructed jmethodID should never be
2139 // seen either. Cache reads of existing jmethodIDs proceed without a
2140 // lock, but cache writes of a new jmethodID requires uniqueness and
2141 // creation of the cache itself requires no leaks so a lock is
2142 // generally acquired in those two cases.
2143 //
2144 // If the RedefineClasses() API has been used, then this cache can
2145 // grow and we'll have transitions from non-NULL to bigger non-NULL.
2146 // Cache creation requires no leaks and we require safety between all
2147 // cache accesses and freeing of the old cache so a lock is generally
2148 // acquired when the RedefineClasses() API has been used.
2149
2150 if (jmeths != NULL) {
2151 // the cache already exists
2152 if (!idnum_can_increment()) {
2153 // the cache can't grow so we can just get the current values
2154 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2155 } else {
2156 // cache can grow so we have to be more careful
2157 if (Threads::number_of_threads() == 0 ||
2158 SafepointSynchronize::is_at_safepoint()) {
2159 // we're single threaded or at a safepoint - no locking needed
2160 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2161 } else {
2162 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2163 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2164 }
2165 }
2166 }
2167 // implied else:
2168 // we need to allocate a cache so default length and id values are good
2169
2170 if (jmeths == NULL || // no cache yet
2171 length <= idnum || // cache is too short
2172 id == NULL) { // cache doesn't contain entry
2173
2174 // This function can be called by the VMThread so we have to do all
2175 // things that might block on a safepoint before grabbing the lock.
2176 // Otherwise, we can deadlock with the VMThread or have a cache
2177 // consistency issue. These vars keep track of what we might have
2178 // to free after the lock is dropped.
2179 jmethodID to_dealloc_id = NULL;
2180 jmethodID* to_dealloc_jmeths = NULL;
2181
2182 // may not allocate new_jmeths or use it if we allocate it
2183 jmethodID* new_jmeths = NULL;
2184 if (length <= idnum) {
2185 // allocate a new cache that might be used
2186 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2187 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2188 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2189 // cache size is stored in element[0], other elements offset by one
2190 new_jmeths[0] = (jmethodID)size;
2191 }
2192
2193 // allocate a new jmethodID that might be used
2194 jmethodID new_id = NULL;
2195 if (method_h->is_old() && !method_h->is_obsolete()) {
2196 // The method passed in is old (but not obsolete), we need to use the current version
2197 Method* current_method = method_with_idnum((int)idnum);
2198 assert(current_method != NULL, "old and but not obsolete, so should exist");
2199 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2200 } else {
2201 // It is the current version of the method or an obsolete method,
2202 // use the version passed in
2203 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2204 }
2205
2206 if (Threads::number_of_threads() == 0 ||
2207 SafepointSynchronize::is_at_safepoint()) {
2208 // we're single threaded or at a safepoint - no locking needed
2209 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2210 &to_dealloc_id, &to_dealloc_jmeths);
2211 } else {
2212 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2213 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2214 &to_dealloc_id, &to_dealloc_jmeths);
2215 }
2216
2217 // The lock has been dropped so we can free resources.
2218 // Free up either the old cache or the new cache if we allocated one.
2219 if (to_dealloc_jmeths != NULL) {
2220 FreeHeap(to_dealloc_jmeths);
2221 }
2222 // free up the new ID since it wasn't needed
2223 if (to_dealloc_id != NULL) {
2224 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2225 }
2226 }
2227 return id;
2228 }
2229
2230 // Figure out how many jmethodIDs haven't been allocated, and make
2231 // sure space for them is pre-allocated. This makes getting all
2232 // method ids much, much faster with classes with more than 8
2233 // methods, and has a *substantial* effect on performance with jvmti
2234 // code that loads all jmethodIDs for all classes.
2235 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2236 int new_jmeths = 0;
2237 int length = methods()->length();
2238 for (int index = start_offset; index < length; index++) {
2239 Method* m = methods()->at(index);
2240 jmethodID id = m->find_jmethod_id_or_null();
2241 if (id == NULL) {
2242 new_jmeths++;
2243 }
2244 }
2245 if (new_jmeths != 0) {
2246 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2247 }
2248 }
2249
2250 // Common code to fetch the jmethodID from the cache or update the
2251 // cache with the new jmethodID. This function should never do anything
2252 // that causes the caller to go to a safepoint or we can deadlock with
2253 // the VMThread or have cache consistency issues.
2254 //
2255 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2256 size_t idnum, jmethodID new_id,
2257 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2258 jmethodID** to_dealloc_jmeths_p) {
2259 assert(new_id != NULL, "sanity check");
2260 assert(to_dealloc_id_p != NULL, "sanity check");
2261 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2262 assert(Threads::number_of_threads() == 0 ||
2263 SafepointSynchronize::is_at_safepoint() ||
2264 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2265
2266 // reacquire the cache - we are locked, single threaded or at a safepoint
2267 jmethodID* jmeths = methods_jmethod_ids_acquire();
2268 jmethodID id = NULL;
2269 size_t length = 0;
2270
2271 if (jmeths == NULL || // no cache yet
2272 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2273 if (jmeths != NULL) {
2274 // copy any existing entries from the old cache
2275 for (size_t index = 0; index < length; index++) {
2276 new_jmeths[index+1] = jmeths[index+1];
2277 }
2278 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2279 }
2280 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2281 } else {
2282 // fetch jmethodID (if any) from the existing cache
2283 id = jmeths[idnum+1];
2284 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2285 }
2286 if (id == NULL) {
2287 // No matching jmethodID in the existing cache or we have a new
2288 // cache or we just grew the cache. This cache write is done here
2289 // by the first thread to win the foot race because a jmethodID
2290 // needs to be unique once it is generally available.
2291 id = new_id;
2292
2293 // The jmethodID cache can be read while unlocked so we have to
2294 // make sure the new jmethodID is complete before installing it
2295 // in the cache.
2296 Atomic::release_store(&jmeths[idnum+1], id);
2297 } else {
2298 *to_dealloc_id_p = new_id; // save new id for later delete
2299 }
2300 return id;
2301 }
2302
2303
2304 // Common code to get the jmethodID cache length and the jmethodID
2305 // value at index idnum if there is one.
2306 //
2307 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2308 size_t idnum, size_t *length_p, jmethodID* id_p) {
2309 assert(cache != NULL, "sanity check");
2310 assert(length_p != NULL, "sanity check");
2311 assert(id_p != NULL, "sanity check");
2312
2313 // cache size is stored in element[0], other elements offset by one
2314 *length_p = (size_t)cache[0];
2315 if (*length_p <= idnum) { // cache is too short
2316 *id_p = NULL;
2317 } else {
2318 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2319 }
2320 }
2321
2322
2323 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2324 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2325 size_t idnum = (size_t)method->method_idnum();
2326 jmethodID* jmeths = methods_jmethod_ids_acquire();
2327 size_t length; // length assigned as debugging crumb
2328 jmethodID id = NULL;
2329 if (jmeths != NULL && // If there is a cache
2330 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2331 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2332 }
2333 return id;
2334 }
2335
2336 inline DependencyContext InstanceKlass::dependencies() {
2337 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2338 return dep_context;
2339 }
2340
2341 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2342 return dependencies().mark_dependent_nmethods(changes);
2343 }
2344
2345 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2346 dependencies().add_dependent_nmethod(nm);
2347 }
2348
2349 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2350 dependencies().remove_dependent_nmethod(nm);
2351 }
2352
2353 void InstanceKlass::clean_dependency_context() {
2354 dependencies().clean_unloading_dependents();
2355 }
2356
2357 #ifndef PRODUCT
2358 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2359 dependencies().print_dependent_nmethods(verbose);
2360 }
2361
2362 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2363 return dependencies().is_dependent_nmethod(nm);
2364 }
2365 #endif //PRODUCT
2366
2367 void InstanceKlass::clean_weak_instanceklass_links() {
2368 clean_implementors_list();
2369 clean_method_data();
2370 }
2371
2372 void InstanceKlass::clean_implementors_list() {
2373 assert(is_loader_alive(), "this klass should be live");
2374 if (is_interface()) {
2375 assert (ClassUnloading, "only called for ClassUnloading");
2376 for (;;) {
2377 // Use load_acquire due to competing with inserts
2378 InstanceKlass* impl = Atomic::load_acquire(adr_implementor());
2379 if (impl != NULL && !impl->is_loader_alive()) {
2380 // NULL this field, might be an unloaded instance klass or NULL
2381 InstanceKlass* volatile* iklass = adr_implementor();
2382 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)NULL) == impl) {
2383 // Successfully unlinking implementor.
2384 if (log_is_enabled(Trace, class, unload)) {
2385 ResourceMark rm;
2386 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2387 }
2388 return;
2389 }
2390 } else {
2391 return;
2392 }
2393 }
2394 }
2395 }
2396
2397 void InstanceKlass::clean_method_data() {
2398 for (int m = 0; m < methods()->length(); m++) {
2399 MethodData* mdo = methods()->at(m)->method_data();
2400 if (mdo != NULL) {
2401 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock());
2402 mdo->clean_method_data(/*always_clean*/false);
2403 }
2404 }
2405 }
2406
2407 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2408 Klass::metaspace_pointers_do(it);
2409
2410 if (log_is_enabled(Trace, cds)) {
2411 ResourceMark rm;
2412 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2413 }
2414
2415 it->push(&_annotations);
2416 it->push((Klass**)&_array_klasses);
2417 if (!is_rewritten()) {
2418 it->push(&_constants, MetaspaceClosure::_writable);
2419 } else {
2420 it->push(&_constants);
2421 }
2422 it->push(&_inner_classes);
2423 #if INCLUDE_JVMTI
2424 it->push(&_previous_versions);
2425 #endif
2426 it->push(&_methods);
2427 it->push(&_default_methods);
2428 it->push(&_local_interfaces);
2429 it->push(&_transitive_interfaces);
2430 it->push(&_method_ordering);
2431 if (!is_rewritten()) {
2432 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2433 } else {
2434 it->push(&_default_vtable_indices);
2435 }
2436 it->push(&_fields);
2437
2438 if (itable_length() > 0) {
2439 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2440 int method_table_offset_in_words = ioe->offset()/wordSize;
2441 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2442 / itableOffsetEntry::size();
2443
2444 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2445 if (ioe->interface_klass() != NULL) {
2446 it->push(ioe->interface_klass_addr());
2447 itableMethodEntry* ime = ioe->first_method_entry(this);
2448 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2449 for (int index = 0; index < n; index ++) {
2450 it->push(ime[index].method_addr());
2451 }
2452 }
2453 }
2454 }
2455
2456 it->push(&_nest_members);
2457 it->push(&_permitted_subclasses);
2458 it->push(&_record_components);
2459 }
2460
2461 void InstanceKlass::remove_unshareable_info() {
2462
2463 if (is_linked()) {
2464 assert(can_be_verified_at_dumptime(), "must be");
2465 // Remember this so we can avoid walking the hierarchy at runtime.
2466 set_verified_at_dump_time();
2467 }
2468
2469 Klass::remove_unshareable_info();
2470
2471 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2472 // Classes are attempted to link during dumping and may fail,
2473 // but these classes are still in the dictionary and class list in CLD.
2474 // If the class has failed verification, there is nothing else to remove.
2475 return;
2476 }
2477
2478 // Reset to the 'allocated' state to prevent any premature accessing to
2479 // a shared class at runtime while the class is still being loaded and
2480 // restored. A class' init_state is set to 'loaded' at runtime when it's
2481 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2482 _init_state = allocated;
2483
2484 { // Otherwise this needs to take out the Compile_lock.
2485 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2486 init_implementor();
2487 }
2488
2489 constants()->remove_unshareable_info();
2490
2491 for (int i = 0; i < methods()->length(); i++) {
2492 Method* m = methods()->at(i);
2493 m->remove_unshareable_info();
2494 }
2495
2496 // do array classes also.
2497 if (array_klasses() != NULL) {
2498 array_klasses()->remove_unshareable_info();
2499 }
2500
2501 // These are not allocated from metaspace. They are safe to set to NULL.
2502 _source_debug_extension = NULL;
2503 _dep_context = NULL;
2504 _osr_nmethods_head = NULL;
2505 #if INCLUDE_JVMTI
2506 _breakpoints = NULL;
2507 _previous_versions = NULL;
2508 _cached_class_file = NULL;
2509 _jvmti_cached_class_field_map = NULL;
2510 #endif
2511
2512 _init_thread = NULL;
2513 _methods_jmethod_ids = NULL;
2514 _jni_ids = NULL;
2515 _oop_map_cache = NULL;
2516 // clear _nest_host to ensure re-load at runtime
2517 _nest_host = NULL;
2518 init_shared_package_entry();
2519 _dep_context_last_cleaned = 0;
2520 }
2521
2522 void InstanceKlass::remove_java_mirror() {
2523 Klass::remove_java_mirror();
2524
2525 // do array classes also.
2526 if (array_klasses() != NULL) {
2527 array_klasses()->remove_java_mirror();
2528 }
2529 }
2530
2531 void InstanceKlass::init_shared_package_entry() {
2532 #if !INCLUDE_CDS_JAVA_HEAP
2533 _package_entry = NULL;
2534 #else
2535 if (!MetaspaceShared::use_full_module_graph()) {
2536 _package_entry = NULL;
2537 } else if (DynamicDumpSharedSpaces) {
2538 if (!MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2539 _package_entry = NULL;
2540 }
2541 } else {
2542 if (is_shared_unregistered_class()) {
2543 _package_entry = NULL;
2544 } else {
2545 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2546 }
2547 }
2548 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2549 #endif
2550 }
2551
2552 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2553 PackageEntry* pkg_entry, TRAPS) {
2554 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2555 // before the InstanceKlass is added to the SystemDictionary. Make
2556 // sure the current state is <loaded.
2557 assert(!is_loaded(), "invalid init state");
2558 assert(!shared_loading_failed(), "Must not try to load failed class again");
2559 set_package(loader_data, pkg_entry, CHECK);
2560 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2561
2562 Array<Method*>* methods = this->methods();
2563 int num_methods = methods->length();
2564 for (int index = 0; index < num_methods; ++index) {
2565 methods->at(index)->restore_unshareable_info(CHECK);
2566 }
2567 #if INCLUDE_JVMTI
2568 if (JvmtiExport::has_redefined_a_class()) {
2569 // Reinitialize vtable because RedefineClasses may have changed some
2570 // entries in this vtable for super classes so the CDS vtable might
2571 // point to old or obsolete entries. RedefineClasses doesn't fix up
2572 // vtables in the shared system dictionary, only the main one.
2573 // It also redefines the itable too so fix that too.
2574 // First fix any default methods that point to a super class that may
2575 // have been redefined.
2576 bool trace_name_printed = false;
2577 adjust_default_methods(&trace_name_printed);
2578 vtable().initialize_vtable();
2579 itable().initialize_itable();
2580 }
2581 #endif
2582
2583 // restore constant pool resolved references
2584 constants()->restore_unshareable_info(CHECK);
2585
2586 if (array_klasses() != NULL) {
2587 // Array classes have null protection domain.
2588 // --> see ArrayKlass::complete_create_array_klass()
2589 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2590 }
2591
2592 // Initialize @ValueBased class annotation
2593 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
2594 set_is_value_based();
2595 }
2596 }
2597
2598 // Check if a class or any of its supertypes has a version older than 50.
2599 // CDS will not perform verification of old classes during dump time because
2600 // without changing the old verifier, the verification constraint cannot be
2601 // retrieved during dump time.
2602 // Verification of archived old classes will be performed during run time.
2603 bool InstanceKlass::can_be_verified_at_dumptime() const {
2604 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2605 return false;
2606 }
2607 if (java_super() != NULL && !java_super()->can_be_verified_at_dumptime()) {
2608 return false;
2609 }
2610 Array<InstanceKlass*>* interfaces = local_interfaces();
2611 int len = interfaces->length();
2612 for (int i = 0; i < len; i++) {
2613 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2614 return false;
2615 }
2616 }
2617 return true;
2618 }
2619
2620 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) {
2621 switch (loader_type) {
2622 case ClassLoader::BOOT_LOADER:
2623 _misc_flags |= _misc_is_shared_boot_class;
2624 break;
2625 case ClassLoader::PLATFORM_LOADER:
2626 _misc_flags |= _misc_is_shared_platform_class;
2627 break;
2628 case ClassLoader::APP_LOADER:
2629 _misc_flags |= _misc_is_shared_app_class;
2630 break;
2631 default:
2632 ShouldNotReachHere();
2633 break;
2634 }
2635 }
2636
2637 void InstanceKlass::assign_class_loader_type() {
2638 ClassLoaderData *cld = class_loader_data();
2639 if (cld->is_boot_class_loader_data()) {
2640 set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
2641 }
2642 else if (cld->is_platform_class_loader_data()) {
2643 set_shared_class_loader_type(ClassLoader::PLATFORM_LOADER);
2644 }
2645 else if (cld->is_system_class_loader_data()) {
2646 set_shared_class_loader_type(ClassLoader::APP_LOADER);
2647 }
2648 }
2649
2650 #if INCLUDE_JVMTI
2651 static void clear_all_breakpoints(Method* m) {
2652 m->clear_all_breakpoints();
2653 }
2654 #endif
2655
2656 void InstanceKlass::unload_class(InstanceKlass* ik) {
2657 // Release dependencies.
2658 ik->dependencies().remove_all_dependents();
2659
2660 // notify the debugger
2661 if (JvmtiExport::should_post_class_unload()) {
2662 JvmtiExport::post_class_unload(ik);
2663 }
2664
2665 // notify ClassLoadingService of class unload
2666 ClassLoadingService::notify_class_unloaded(ik);
2667
2668 SystemDictionaryShared::handle_class_unloading(ik);
2669
2670 if (log_is_enabled(Info, class, unload)) {
2671 ResourceMark rm;
2672 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik));
2673 }
2674
2675 Events::log_class_unloading(Thread::current(), ik);
2676
2677 #if INCLUDE_JFR
2678 assert(ik != NULL, "invariant");
2679 EventClassUnload event;
2680 event.set_unloadedClass(ik);
2681 event.set_definingClassLoader(ik->class_loader_data());
2682 event.commit();
2683 #endif
2684 }
2685
2686 static void method_release_C_heap_structures(Method* m) {
2687 m->release_C_heap_structures();
2688 }
2689
2690 void InstanceKlass::release_C_heap_structures() {
2691
2692 // Clean up C heap
2693 release_C_heap_structures_internal();
2694 constants()->release_C_heap_structures();
2695
2696 // Deallocate and call destructors for MDO mutexes
2697 methods_do(method_release_C_heap_structures);
2698 }
2699
2700 void InstanceKlass::release_C_heap_structures_internal() {
2701 Klass::release_C_heap_structures();
2702
2703 // Can't release the constant pool here because the constant pool can be
2704 // deallocated separately from the InstanceKlass for default methods and
2705 // redefine classes.
2706
2707 // Deallocate oop map cache
2708 if (_oop_map_cache != NULL) {
2709 delete _oop_map_cache;
2710 _oop_map_cache = NULL;
2711 }
2712
2713 // Deallocate JNI identifiers for jfieldIDs
2714 JNIid::deallocate(jni_ids());
2715 set_jni_ids(NULL);
2716
2717 jmethodID* jmeths = methods_jmethod_ids_acquire();
2718 if (jmeths != (jmethodID*)NULL) {
2719 release_set_methods_jmethod_ids(NULL);
2720 FreeHeap(jmeths);
2721 }
2722
2723 assert(_dep_context == NULL,
2724 "dependencies should already be cleaned");
2725
2726 #if INCLUDE_JVMTI
2727 // Deallocate breakpoint records
2728 if (breakpoints() != 0x0) {
2729 methods_do(clear_all_breakpoints);
2730 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2731 }
2732
2733 // deallocate the cached class file
2734 if (_cached_class_file != NULL) {
2735 os::free(_cached_class_file);
2736 _cached_class_file = NULL;
2737 }
2738 #endif
2739
2740 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2741 }
2742
2743 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2744 if (array == NULL) {
2745 _source_debug_extension = NULL;
2746 } else {
2747 // Adding one to the attribute length in order to store a null terminator
2748 // character could cause an overflow because the attribute length is
2749 // already coded with an u4 in the classfile, but in practice, it's
2750 // unlikely to happen.
2751 assert((length+1) > length, "Overflow checking");
2752 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2753 for (int i = 0; i < length; i++) {
2754 sde[i] = array[i];
2755 }
2756 sde[length] = '\0';
2757 _source_debug_extension = sde;
2758 }
2759 }
2760
2761 const char* InstanceKlass::signature_name() const {
2762 int hash_len = 0;
2763 char hash_buf[40];
2764
2765 // Get the internal name as a c string
2766 const char* src = (const char*) (name()->as_C_string());
2767 const int src_length = (int)strlen(src);
2768
2769 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2770
2771 // Add L as type indicator
2772 int dest_index = 0;
2773 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2774
2775 // Add the actual class name
2776 for (int src_index = 0; src_index < src_length; ) {
2777 dest[dest_index++] = src[src_index++];
2778 }
2779
2780 if (is_hidden()) { // Replace the last '+' with a '.'.
2781 for (int index = (int)src_length; index > 0; index--) {
2782 if (dest[index] == '+') {
2783 dest[index] = JVM_SIGNATURE_DOT;
2784 break;
2785 }
2786 }
2787 }
2788
2789 // If we have a hash, append it
2790 for (int hash_index = 0; hash_index < hash_len; ) {
2791 dest[dest_index++] = hash_buf[hash_index++];
2792 }
2793
2794 // Add the semicolon and the NULL
2795 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
2796 dest[dest_index] = '\0';
2797 return dest;
2798 }
2799
2800 ModuleEntry* InstanceKlass::module() const {
2801 if (is_hidden() &&
2802 in_unnamed_package() &&
2803 class_loader_data()->has_class_mirror_holder()) {
2804 // For a non-strong hidden class defined to an unnamed package,
2805 // its (class held) CLD will not have an unnamed module created for it.
2806 // Two choices to find the correct ModuleEntry:
2807 // 1. If hidden class is within a nest, use nest host's module
2808 // 2. Find the unnamed module off from the class loader
2809 // For now option #2 is used since a nest host is not set until
2810 // after the instance class is created in jvm_lookup_define_class().
2811 if (class_loader_data()->is_boot_class_loader_data()) {
2812 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
2813 } else {
2814 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
2815 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
2816 return java_lang_Module::module_entry(module);
2817 }
2818 }
2819
2820 // Class is in a named package
2821 if (!in_unnamed_package()) {
2822 return _package_entry->module();
2823 }
2824
2825 // Class is in an unnamed package, return its loader's unnamed module
2826 return class_loader_data()->unnamed_module();
2827 }
2828
2829 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
2830
2831 // ensure java/ packages only loaded by boot or platform builtin loaders
2832 // not needed for shared class since CDS does not archive prohibited classes.
2833 if (!is_shared()) {
2834 check_prohibited_package(name(), loader_data, CHECK);
2835 }
2836
2837 if (is_shared() && _package_entry != NULL) {
2838 if (MetaspaceShared::use_full_module_graph() && _package_entry == pkg_entry) {
2839 // we can use the saved package
2840 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
2841 return;
2842 } else {
2843 _package_entry = NULL;
2844 }
2845 }
2846
2847 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
2848 // it returns, so we need to decrement it when the current function exits.
2849 TempNewSymbol from_class_name =
2850 (pkg_entry != NULL) ? NULL : ClassLoader::package_from_class_name(name());
2851
2852 Symbol* pkg_name;
2853 if (pkg_entry != NULL) {
2854 pkg_name = pkg_entry->name();
2855 } else {
2856 pkg_name = from_class_name;
2857 }
2858
2859 if (pkg_name != NULL && loader_data != NULL) {
2860
2861 // Find in class loader's package entry table.
2862 _package_entry = pkg_entry != NULL ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
2863
2864 // If the package name is not found in the loader's package
2865 // entry table, it is an indication that the package has not
2866 // been defined. Consider it defined within the unnamed module.
2867 if (_package_entry == NULL) {
2868
2869 if (!ModuleEntryTable::javabase_defined()) {
2870 // Before java.base is defined during bootstrapping, define all packages in
2871 // the java.base module. If a non-java.base package is erroneously placed
2872 // in the java.base module it will be caught later when java.base
2873 // is defined by ModuleEntryTable::verify_javabase_packages check.
2874 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2875 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2876 } else {
2877 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2878 _package_entry = loader_data->packages()->lookup(pkg_name,
2879 loader_data->unnamed_module());
2880 }
2881
2882 // A package should have been successfully created
2883 DEBUG_ONLY(ResourceMark rm(THREAD));
2884 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2885 name()->as_C_string(), loader_data->loader_name_and_id());
2886 }
2887
2888 if (log_is_enabled(Debug, module)) {
2889 ResourceMark rm(THREAD);
2890 ModuleEntry* m = _package_entry->module();
2891 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2892 external_name(),
2893 pkg_name->as_C_string(),
2894 loader_data->loader_name_and_id(),
2895 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2896 }
2897 } else {
2898 ResourceMark rm(THREAD);
2899 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2900 external_name(),
2901 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2902 UNNAMED_MODULE);
2903 }
2904 }
2905
2906 // Function set_classpath_index ensures that for a non-null _package_entry
2907 // of the InstanceKlass, the entry is in the boot loader's package entry table.
2908 // It then sets the classpath_index in the package entry record.
2909 //
2910 // The classpath_index field is used to find the entry on the boot loader class
2911 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
2912 // in an unnamed module. It is also used to indicate (for all packages whose
2913 // classes are loaded by the boot loader) that at least one of the package's
2914 // classes has been loaded.
2915 void InstanceKlass::set_classpath_index(s2 path_index) {
2916 if (_package_entry != NULL) {
2917 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
2918 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
2919 assert(path_index != -1, "Unexpected classpath_index");
2920 _package_entry->set_classpath_index(path_index);
2921 }
2922 }
2923
2924 // different versions of is_same_class_package
2925
2926 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2927 oop classloader1 = this->class_loader();
2928 PackageEntry* classpkg1 = this->package();
2929 if (class2->is_objArray_klass()) {
2930 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2931 }
2932
2933 oop classloader2;
2934 PackageEntry* classpkg2;
2935 if (class2->is_instance_klass()) {
2936 classloader2 = class2->class_loader();
2937 classpkg2 = class2->package();
2938 } else {
2939 assert(class2->is_typeArray_klass(), "should be type array");
2940 classloader2 = NULL;
2941 classpkg2 = NULL;
2942 }
2943
2944 // Same package is determined by comparing class loader
2945 // and package entries. Both must be the same. This rule
2946 // applies even to classes that are defined in the unnamed
2947 // package, they still must have the same class loader.
2948 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2949 return true;
2950 }
2951
2952 return false;
2953 }
2954
2955 // return true if this class and other_class are in the same package. Classloader
2956 // and classname information is enough to determine a class's package
2957 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2958 const Symbol* other_class_name) const {
2959 if (class_loader() != other_class_loader) {
2960 return false;
2961 }
2962 if (name()->fast_compare(other_class_name) == 0) {
2963 return true;
2964 }
2965
2966 {
2967 ResourceMark rm;
2968
2969 bool bad_class_name = false;
2970 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
2971 if (bad_class_name) {
2972 return false;
2973 }
2974 // Check that package_from_class_name() returns NULL, not "", if there is no package.
2975 assert(other_pkg == NULL || other_pkg->utf8_length() > 0, "package name is empty string");
2976
2977 const Symbol* const this_package_name =
2978 this->package() != NULL ? this->package()->name() : NULL;
2979
2980 if (this_package_name == NULL || other_pkg == NULL) {
2981 // One of the two doesn't have a package. Only return true if the other
2982 // one also doesn't have a package.
2983 return this_package_name == other_pkg;
2984 }
2985
2986 // Check if package is identical
2987 return this_package_name->fast_compare(other_pkg) == 0;
2988 }
2989 }
2990
2991 static bool is_prohibited_package_slow(Symbol* class_name) {
2992 // Caller has ResourceMark
2993 int length;
2994 jchar* unicode = class_name->as_unicode(length);
2995 return (length >= 5 &&
2996 unicode[0] == 'j' &&
2997 unicode[1] == 'a' &&
2998 unicode[2] == 'v' &&
2999 unicode[3] == 'a' &&
3000 unicode[4] == '/');
3001 }
3002
3003 // Only boot and platform class loaders can define classes in "java/" packages.
3004 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3005 ClassLoaderData* loader_data,
3006 TRAPS) {
3007 if (!loader_data->is_boot_class_loader_data() &&
3008 !loader_data->is_platform_class_loader_data() &&
3009 class_name != NULL && class_name->utf8_length() >= 5) {
3010 ResourceMark rm(THREAD);
3011 bool prohibited;
3012 const u1* base = class_name->base();
3013 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3014 prohibited = is_prohibited_package_slow(class_name);
3015 } else {
3016 char* name = class_name->as_C_string();
3017 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3018 }
3019 if (prohibited) {
3020 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3021 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
3022 char* name = pkg_name->as_C_string();
3023 const char* class_loader_name = loader_data->loader_name_and_id();
3024 StringUtils::replace_no_expand(name, "/", ".");
3025 const char* msg_text1 = "Class loader (instance of): ";
3026 const char* msg_text2 = " tried to load prohibited package name: ";
3027 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3028 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3029 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3030 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3031 }
3032 }
3033 return;
3034 }
3035
3036 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3037 constantPoolHandle i_cp(THREAD, constants());
3038 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3039 int ioff = iter.inner_class_info_index();
3040 if (ioff != 0) {
3041 // Check to see if the name matches the class we're looking for
3042 // before attempting to find the class.
3043 if (i_cp->klass_name_at_matches(this, ioff)) {
3044 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3045 if (this == inner_klass) {
3046 *ooff = iter.outer_class_info_index();
3047 *noff = iter.inner_name_index();
3048 return true;
3049 }
3050 }
3051 }
3052 }
3053 return false;
3054 }
3055
3056 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3057 InstanceKlass* outer_klass = NULL;
3058 *inner_is_member = false;
3059 int ooff = 0, noff = 0;
3060 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3061 if (has_inner_classes_attr) {
3062 constantPoolHandle i_cp(THREAD, constants());
3063 if (ooff != 0) {
3064 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3065 outer_klass = InstanceKlass::cast(ok);
3066 *inner_is_member = true;
3067 }
3068 if (NULL == outer_klass) {
3069 // It may be a local class; try for that.
3070 int encl_method_class_idx = enclosing_method_class_index();
3071 if (encl_method_class_idx != 0) {
3072 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3073 outer_klass = InstanceKlass::cast(ok);
3074 *inner_is_member = false;
3075 }
3076 }
3077 }
3078
3079 // If no inner class attribute found for this class.
3080 if (NULL == outer_klass) return NULL;
3081
3082 // Throws an exception if outer klass has not declared k as an inner klass
3083 // We need evidence that each klass knows about the other, or else
3084 // the system could allow a spoof of an inner class to gain access rights.
3085 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3086 return outer_klass;
3087 }
3088
3089 jint InstanceKlass::compute_modifier_flags() const {
3090 jint access = access_flags().as_int();
3091
3092 // But check if it happens to be member class.
3093 InnerClassesIterator iter(this);
3094 for (; !iter.done(); iter.next()) {
3095 int ioff = iter.inner_class_info_index();
3096 // Inner class attribute can be zero, skip it.
3097 // Strange but true: JVM spec. allows null inner class refs.
3098 if (ioff == 0) continue;
3099
3100 // only look at classes that are already loaded
3101 // since we are looking for the flags for our self.
3102 Symbol* inner_name = constants()->klass_name_at(ioff);
3103 if (name() == inner_name) {
3104 // This is really a member class.
3105 access = iter.inner_access_flags();
3106 break;
3107 }
3108 }
3109 // Remember to strip ACC_SUPER bit
3110 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3111 }
3112
3113 jint InstanceKlass::jvmti_class_status() const {
3114 jint result = 0;
3115
3116 if (is_linked()) {
3117 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3118 }
3119
3120 if (is_initialized()) {
3121 assert(is_linked(), "Class status is not consistent");
3122 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3123 }
3124 if (is_in_error_state()) {
3125 result |= JVMTI_CLASS_STATUS_ERROR;
3126 }
3127 return result;
3128 }
3129
3130 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3131 bool implements_interface; // initialized by method_at_itable_or_null
3132 Method* m = method_at_itable_or_null(holder, index,
3133 implements_interface); // out parameter
3134 if (m != NULL) {
3135 assert(implements_interface, "sanity");
3136 return m;
3137 } else if (implements_interface) {
3138 // Throw AbstractMethodError since corresponding itable slot is empty.
3139 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3140 } else {
3141 // If the interface isn't implemented by the receiver class,
3142 // the VM should throw IncompatibleClassChangeError.
3143 ResourceMark rm(THREAD);
3144 stringStream ss;
3145 bool same_module = (module() == holder->module());
3146 ss.print("Receiver class %s does not implement "
3147 "the interface %s defining the method to be called "
3148 "(%s%s%s)",
3149 external_name(), holder->external_name(),
3150 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3151 (same_module) ? "" : "; ",
3152 (same_module) ? "" : holder->class_in_module_of_loader());
3153 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3154 }
3155 }
3156
3157 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3158 klassItable itable(this);
3159 for (int i = 0; i < itable.size_offset_table(); i++) {
3160 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3161 if (offset_entry->interface_klass() == holder) {
3162 implements_interface = true;
3163 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3164 Method* m = ime[index].method();
3165 return m;
3166 }
3167 }
3168 implements_interface = false;
3169 return NULL; // offset entry not found
3170 }
3171
3172 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3173 assert(is_linked(), "required");
3174 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3175 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3176
3177 int vtable_index = Method::invalid_vtable_index;
3178 Symbol* name = intf_method->name();
3179 Symbol* signature = intf_method->signature();
3180
3181 // First check in default method array
3182 if (!intf_method->is_abstract() && default_methods() != NULL) {
3183 int index = find_method_index(default_methods(),
3184 name, signature,
3185 Klass::OverpassLookupMode::find,
3186 Klass::StaticLookupMode::find,
3187 Klass::PrivateLookupMode::find);
3188 if (index >= 0) {
3189 vtable_index = default_vtable_indices()->at(index);
3190 }
3191 }
3192 if (vtable_index == Method::invalid_vtable_index) {
3193 // get vtable_index for miranda methods
3194 klassVtable vt = vtable();
3195 vtable_index = vt.index_of_miranda(name, signature);
3196 }
3197 return vtable_index;
3198 }
3199
3200 #if INCLUDE_JVMTI
3201 // update default_methods for redefineclasses for methods that are
3202 // not yet in the vtable due to concurrent subclass define and superinterface
3203 // redefinition
3204 // Note: those in the vtable, should have been updated via adjust_method_entries
3205 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3206 // search the default_methods for uses of either obsolete or EMCP methods
3207 if (default_methods() != NULL) {
3208 for (int index = 0; index < default_methods()->length(); index ++) {
3209 Method* old_method = default_methods()->at(index);
3210 if (old_method == NULL || !old_method->is_old()) {
3211 continue; // skip uninteresting entries
3212 }
3213 assert(!old_method->is_deleted(), "default methods may not be deleted");
3214 Method* new_method = old_method->get_new_method();
3215 default_methods()->at_put(index, new_method);
3216
3217 if (log_is_enabled(Info, redefine, class, update)) {
3218 ResourceMark rm;
3219 if (!(*trace_name_printed)) {
3220 log_info(redefine, class, update)
3221 ("adjust: klassname=%s default methods from name=%s",
3222 external_name(), old_method->method_holder()->external_name());
3223 *trace_name_printed = true;
3224 }
3225 log_debug(redefine, class, update, vtables)
3226 ("default method update: %s(%s) ",
3227 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3228 }
3229 }
3230 }
3231 }
3232 #endif // INCLUDE_JVMTI
3233
3234 // On-stack replacement stuff
3235 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3236 assert_lock_strong(CompiledMethod_lock);
3237 #ifndef PRODUCT
3238 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3239 assert(prev == NULL || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3240 "redundant OSR recompilation detected. memory leak in CodeCache!");
3241 #endif
3242 // only one compilation can be active
3243 assert(n->is_osr_method(), "wrong kind of nmethod");
3244 n->set_osr_link(osr_nmethods_head());
3245 set_osr_nmethods_head(n);
3246 // Raise the highest osr level if necessary
3247 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3248
3249 // Get rid of the osr methods for the same bci that have lower levels.
3250 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3251 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3252 if (inv != NULL && inv->is_in_use()) {
3253 inv->make_not_entrant();
3254 }
3255 }
3256 }
3257
3258 // Remove osr nmethod from the list. Return true if found and removed.
3259 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3260 // This is a short non-blocking critical region, so the no safepoint check is ok.
3261 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock
3262 , Mutex::_no_safepoint_check_flag);
3263 assert(n->is_osr_method(), "wrong kind of nmethod");
3264 nmethod* last = NULL;
3265 nmethod* cur = osr_nmethods_head();
3266 int max_level = CompLevel_none; // Find the max comp level excluding n
3267 Method* m = n->method();
3268 // Search for match
3269 bool found = false;
3270 while(cur != NULL && cur != n) {
3271 if (m == cur->method()) {
3272 // Find max level before n
3273 max_level = MAX2(max_level, cur->comp_level());
3274 }
3275 last = cur;
3276 cur = cur->osr_link();
3277 }
3278 nmethod* next = NULL;
3279 if (cur == n) {
3280 found = true;
3281 next = cur->osr_link();
3282 if (last == NULL) {
3283 // Remove first element
3284 set_osr_nmethods_head(next);
3285 } else {
3286 last->set_osr_link(next);
3287 }
3288 }
3289 n->set_osr_link(NULL);
3290 cur = next;
3291 while (cur != NULL) {
3292 // Find max level after n
3293 if (m == cur->method()) {
3294 max_level = MAX2(max_level, cur->comp_level());
3295 }
3296 cur = cur->osr_link();
3297 }
3298 m->set_highest_osr_comp_level(max_level);
3299 return found;
3300 }
3301
3302 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3303 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3304 Mutex::_no_safepoint_check_flag);
3305 nmethod* osr = osr_nmethods_head();
3306 int found = 0;
3307 while (osr != NULL) {
3308 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3309 if (osr->method() == m) {
3310 osr->mark_for_deoptimization();
3311 found++;
3312 }
3313 osr = osr->osr_link();
3314 }
3315 return found;
3316 }
3317
3318 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3319 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3320 Mutex::_no_safepoint_check_flag);
3321 nmethod* osr = osr_nmethods_head();
3322 nmethod* best = NULL;
3323 while (osr != NULL) {
3324 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3325 // There can be a time when a c1 osr method exists but we are waiting
3326 // for a c2 version. When c2 completes its osr nmethod we will trash
3327 // the c1 version and only be able to find the c2 version. However
3328 // while we overflow in the c1 code at back branches we don't want to
3329 // try and switch to the same code as we are already running
3330
3331 if (osr->method() == m &&
3332 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3333 if (match_level) {
3334 if (osr->comp_level() == comp_level) {
3335 // Found a match - return it.
3336 return osr;
3337 }
3338 } else {
3339 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3340 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3341 // Found the best possible - return it.
3342 return osr;
3343 }
3344 best = osr;
3345 }
3346 }
3347 }
3348 osr = osr->osr_link();
3349 }
3350
3351 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set");
3352 if (best != NULL && best->comp_level() >= comp_level) {
3353 return best;
3354 }
3355 return NULL;
3356 }
3357
3358 // -----------------------------------------------------------------------------------------------------
3359 // Printing
3360
3361 #define BULLET " - "
3362
3363 static const char* state_names[] = {
3364 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3365 };
3366
3367 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3368 for (int i = 0; i < len; i++) {
3369 intptr_t e = start[i];
3370 st->print("%d : " INTPTR_FORMAT, i, e);
3371 if (MetaspaceObj::is_valid((Metadata*)e)) {
3372 st->print(" ");
3373 ((Metadata*)e)->print_value_on(st);
3374 }
3375 st->cr();
3376 }
3377 }
3378
3379 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3380 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3381 }
3382
3383 void InstanceKlass::print_on(outputStream* st) const {
3384 assert(is_klass(), "must be klass");
3385 Klass::print_on(st);
3386
3387 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3388 st->print(BULLET"klass size: %d", size()); st->cr();
3389 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3390 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3391 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3392 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3393 st->print(BULLET"sub: ");
3394 Klass* sub = subklass();
3395 int n;
3396 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3397 if (n < MaxSubklassPrintSize) {
3398 sub->print_value_on(st);
3399 st->print(" ");
3400 }
3401 }
3402 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3403 st->cr();
3404
3405 if (is_interface()) {
3406 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3407 if (nof_implementors() == 1) {
3408 st->print_cr(BULLET"implementor: ");
3409 st->print(" ");
3410 implementor()->print_value_on(st);
3411 st->cr();
3412 }
3413 }
3414
3415 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3416 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3417 if (Verbose || WizardMode) {
3418 Array<Method*>* method_array = methods();
3419 for (int i = 0; i < method_array->length(); i++) {
3420 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3421 }
3422 }
3423 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3424 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3425 if (Verbose && default_methods() != NULL) {
3426 Array<Method*>* method_array = default_methods();
3427 for (int i = 0; i < method_array->length(); i++) {
3428 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3429 }
3430 }
3431 if (default_vtable_indices() != NULL) {
3432 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3433 }
3434 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3435 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3436 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3437 if (class_loader_data() != NULL) {
3438 st->print(BULLET"class loader data: ");
3439 class_loader_data()->print_value_on(st);
3440 st->cr();
3441 }
3442 if (source_file_name() != NULL) {
3443 st->print(BULLET"source file: ");
3444 source_file_name()->print_value_on(st);
3445 st->cr();
3446 }
3447 if (source_debug_extension() != NULL) {
3448 st->print(BULLET"source debug extension: ");
3449 st->print("%s", source_debug_extension());
3450 st->cr();
3451 }
3452 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3453 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3454 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3455 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3456 {
3457 bool have_pv = false;
3458 // previous versions are linked together through the InstanceKlass
3459 for (InstanceKlass* pv_node = previous_versions();
3460 pv_node != NULL;
3461 pv_node = pv_node->previous_versions()) {
3462 if (!have_pv)
3463 st->print(BULLET"previous version: ");
3464 have_pv = true;
3465 pv_node->constants()->print_value_on(st);
3466 }
3467 if (have_pv) st->cr();
3468 }
3469
3470 if (generic_signature() != NULL) {
3471 st->print(BULLET"generic signature: ");
3472 generic_signature()->print_value_on(st);
3473 st->cr();
3474 }
3475 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3476 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3477 if (record_components() != NULL) {
3478 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3479 }
3480 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3481 if (java_mirror() != NULL) {
3482 st->print(BULLET"java mirror: ");
3483 java_mirror()->print_value_on(st);
3484 st->cr();
3485 } else {
3486 st->print_cr(BULLET"java mirror: NULL");
3487 }
3488 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3489 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3490 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3491 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3492 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3493 FieldPrinter print_static_field(st);
3494 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3495 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3496 FieldPrinter print_nonstatic_field(st);
3497 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3498 ik->print_nonstatic_fields(&print_nonstatic_field);
3499
3500 st->print(BULLET"non-static oop maps: ");
3501 OopMapBlock* map = start_of_nonstatic_oop_maps();
3502 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3503 while (map < end_map) {
3504 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3505 map++;
3506 }
3507 st->cr();
3508 }
3509
3510 void InstanceKlass::print_value_on(outputStream* st) const {
3511 assert(is_klass(), "must be klass");
3512 if (Verbose || WizardMode) access_flags().print_on(st);
3513 name()->print_value_on(st);
3514 }
3515
3516 void FieldPrinter::do_field(fieldDescriptor* fd) {
3517 _st->print(BULLET);
3518 if (_obj == NULL) {
3519 fd->print_on(_st);
3520 _st->cr();
3521 } else {
3522 fd->print_on_for(_st, _obj);
3523 _st->cr();
3524 }
3525 }
3526
3527
3528 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3529 Klass::oop_print_on(obj, st);
3530
3531 if (this == vmClasses::String_klass()) {
3532 typeArrayOop value = java_lang_String::value(obj);
3533 juint length = java_lang_String::length(obj);
3534 if (value != NULL &&
3535 value->is_typeArray() &&
3536 length <= (juint) value->length()) {
3537 st->print(BULLET"string: ");
3538 java_lang_String::print(obj, st);
3539 st->cr();
3540 }
3541 }
3542
3543 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3544 FieldPrinter print_field(st, obj);
3545 print_nonstatic_fields(&print_field);
3546
3547 if (this == vmClasses::Class_klass()) {
3548 st->print(BULLET"signature: ");
3549 java_lang_Class::print_signature(obj, st);
3550 st->cr();
3551 Klass* real_klass = java_lang_Class::as_Klass(obj);
3552 if (real_klass != NULL && real_klass->is_instance_klass()) {
3553 st->print_cr(BULLET"---- static fields (%d words):", java_lang_Class::static_oop_field_count(obj));
3554 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3555 }
3556 } else if (this == vmClasses::MethodType_klass()) {
3557 st->print(BULLET"signature: ");
3558 java_lang_invoke_MethodType::print_signature(obj, st);
3559 st->cr();
3560 }
3561 }
3562
3563 #ifndef PRODUCT
3564
3565 bool InstanceKlass::verify_itable_index(int i) {
3566 int method_count = klassItable::method_count_for_interface(this);
3567 assert(i >= 0 && i < method_count, "index out of bounds");
3568 return true;
3569 }
3570
3571 #endif //PRODUCT
3572
3573 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3574 st->print("a ");
3575 name()->print_value_on(st);
3576 obj->print_address_on(st);
3577 if (this == vmClasses::String_klass()
3578 && java_lang_String::value(obj) != NULL) {
3579 ResourceMark rm;
3580 int len = java_lang_String::length(obj);
3581 int plen = (len < 24 ? len : 12);
3582 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3583 st->print(" = \"%s\"", str);
3584 if (len > plen)
3585 st->print("...[%d]", len);
3586 } else if (this == vmClasses::Class_klass()) {
3587 Klass* k = java_lang_Class::as_Klass(obj);
3588 st->print(" = ");
3589 if (k != NULL) {
3590 k->print_value_on(st);
3591 } else {
3592 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3593 st->print("%s", tname ? tname : "type?");
3594 }
3595 } else if (this == vmClasses::MethodType_klass()) {
3596 st->print(" = ");
3597 java_lang_invoke_MethodType::print_signature(obj, st);
3598 } else if (java_lang_boxing_object::is_instance(obj)) {
3599 st->print(" = ");
3600 java_lang_boxing_object::print(obj, st);
3601 } else if (this == vmClasses::LambdaForm_klass()) {
3602 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3603 if (vmentry != NULL) {
3604 st->print(" => ");
3605 vmentry->print_value_on(st);
3606 }
3607 } else if (this == vmClasses::MemberName_klass()) {
3608 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3609 if (vmtarget != NULL) {
3610 st->print(" = ");
3611 vmtarget->print_value_on(st);
3612 } else {
3613 oop clazz = java_lang_invoke_MemberName::clazz(obj);
3614 oop name = java_lang_invoke_MemberName::name(obj);
3615 if (clazz != NULL) {
3616 clazz->print_value_on(st);
3617 } else {
3618 st->print("NULL");
3619 }
3620 st->print(".");
3621 if (name != NULL) {
3622 name->print_value_on(st);
3623 } else {
3624 st->print("NULL");
3625 }
3626 }
3627 }
3628 }
3629
3630 const char* InstanceKlass::internal_name() const {
3631 return external_name();
3632 }
3633
3634 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3635 const ModuleEntry* module_entry,
3636 const ClassFileStream* cfs) const {
3637 if (ClassListWriter::is_enabled()) {
3638 ClassListWriter::write(this, cfs);
3639 }
3640
3641 if (!log_is_enabled(Info, class, load)) {
3642 return;
3643 }
3644
3645 ResourceMark rm;
3646 LogMessage(class, load) msg;
3647 stringStream info_stream;
3648
3649 // Name and class hierarchy info
3650 info_stream.print("%s", external_name());
3651
3652 // Source
3653 if (cfs != NULL) {
3654 if (cfs->source() != NULL) {
3655 const char* module_name = (module_entry->name() == NULL) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
3656 if (module_name != NULL) {
3657 // When the boot loader created the stream, it didn't know the module name
3658 // yet. Let's format it now.
3659 if (cfs->from_boot_loader_modules_image()) {
3660 info_stream.print(" source: jrt:/%s", module_name);
3661 } else {
3662 info_stream.print(" source: %s", cfs->source());
3663 }
3664 } else {
3665 info_stream.print(" source: %s", cfs->source());
3666 }
3667 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3668 Thread* current = Thread::current();
3669 Klass* caller = current->is_Java_thread() ?
3670 JavaThread::cast(current)->security_get_caller_class(1):
3671 NULL;
3672 // caller can be NULL, for example, during a JVMTI VM_Init hook
3673 if (caller != NULL) {
3674 info_stream.print(" source: instance of %s", caller->external_name());
3675 } else {
3676 // source is unknown
3677 }
3678 } else {
3679 oop class_loader = loader_data->class_loader();
3680 info_stream.print(" source: %s", class_loader->klass()->external_name());
3681 }
3682 } else {
3683 assert(this->is_shared(), "must be");
3684 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3685 info_stream.print(" source: shared objects file (top)");
3686 } else {
3687 info_stream.print(" source: shared objects file");
3688 }
3689 }
3690
3691 msg.info("%s", info_stream.as_string());
3692
3693 if (log_is_enabled(Debug, class, load)) {
3694 stringStream debug_stream;
3695
3696 // Class hierarchy info
3697 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3698 p2i(this), p2i(superklass()));
3699
3700 // Interfaces
3701 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3702 debug_stream.print(" interfaces:");
3703 int length = local_interfaces()->length();
3704 for (int i = 0; i < length; i++) {
3705 debug_stream.print(" " INTPTR_FORMAT,
3706 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3707 }
3708 }
3709
3710 // Class loader
3711 debug_stream.print(" loader: [");
3712 loader_data->print_value_on(&debug_stream);
3713 debug_stream.print("]");
3714
3715 // Classfile checksum
3716 if (cfs) {
3717 debug_stream.print(" bytes: %d checksum: %08x",
3718 cfs->length(),
3719 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3720 cfs->length()));
3721 }
3722
3723 msg.debug("%s", debug_stream.as_string());
3724 }
3725 }
3726
3727 // Verification
3728
3729 class VerifyFieldClosure: public BasicOopIterateClosure {
3730 protected:
3731 template <class T> void do_oop_work(T* p) {
3732 oop obj = RawAccess<>::oop_load(p);
3733 if (!oopDesc::is_oop_or_null(obj)) {
3734 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3735 Universe::print_on(tty);
3736 guarantee(false, "boom");
3737 }
3738 }
3739 public:
3740 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3741 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3742 };
3743
3744 void InstanceKlass::verify_on(outputStream* st) {
3745 #ifndef PRODUCT
3746 // Avoid redundant verifies, this really should be in product.
3747 if (_verify_count == Universe::verify_count()) return;
3748 _verify_count = Universe::verify_count();
3749 #endif
3750
3751 // Verify Klass
3752 Klass::verify_on(st);
3753
3754 // Verify that klass is present in ClassLoaderData
3755 guarantee(class_loader_data()->contains_klass(this),
3756 "this class isn't found in class loader data");
3757
3758 // Verify vtables
3759 if (is_linked()) {
3760 // $$$ This used to be done only for m/s collections. Doing it
3761 // always seemed a valid generalization. (DLD -- 6/00)
3762 vtable().verify(st);
3763 }
3764
3765 // Verify first subklass
3766 if (subklass() != NULL) {
3767 guarantee(subklass()->is_klass(), "should be klass");
3768 }
3769
3770 // Verify siblings
3771 Klass* super = this->super();
3772 Klass* sib = next_sibling();
3773 if (sib != NULL) {
3774 if (sib == this) {
3775 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3776 }
3777
3778 guarantee(sib->is_klass(), "should be klass");
3779 guarantee(sib->super() == super, "siblings should have same superklass");
3780 }
3781
3782 // Verify local interfaces
3783 if (local_interfaces()) {
3784 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3785 for (int j = 0; j < local_interfaces->length(); j++) {
3786 InstanceKlass* e = local_interfaces->at(j);
3787 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3788 }
3789 }
3790
3791 // Verify transitive interfaces
3792 if (transitive_interfaces() != NULL) {
3793 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3794 for (int j = 0; j < transitive_interfaces->length(); j++) {
3795 InstanceKlass* e = transitive_interfaces->at(j);
3796 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3797 }
3798 }
3799
3800 // Verify methods
3801 if (methods() != NULL) {
3802 Array<Method*>* methods = this->methods();
3803 for (int j = 0; j < methods->length(); j++) {
3804 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3805 }
3806 for (int j = 0; j < methods->length() - 1; j++) {
3807 Method* m1 = methods->at(j);
3808 Method* m2 = methods->at(j + 1);
3809 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3810 }
3811 }
3812
3813 // Verify method ordering
3814 if (method_ordering() != NULL) {
3815 Array<int>* method_ordering = this->method_ordering();
3816 int length = method_ordering->length();
3817 if (JvmtiExport::can_maintain_original_method_order() ||
3818 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
3819 guarantee(length == methods()->length(), "invalid method ordering length");
3820 jlong sum = 0;
3821 for (int j = 0; j < length; j++) {
3822 int original_index = method_ordering->at(j);
3823 guarantee(original_index >= 0, "invalid method ordering index");
3824 guarantee(original_index < length, "invalid method ordering index");
3825 sum += original_index;
3826 }
3827 // Verify sum of indices 0,1,...,length-1
3828 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3829 } else {
3830 guarantee(length == 0, "invalid method ordering length");
3831 }
3832 }
3833
3834 // Verify default methods
3835 if (default_methods() != NULL) {
3836 Array<Method*>* methods = this->default_methods();
3837 for (int j = 0; j < methods->length(); j++) {
3838 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3839 }
3840 for (int j = 0; j < methods->length() - 1; j++) {
3841 Method* m1 = methods->at(j);
3842 Method* m2 = methods->at(j + 1);
3843 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3844 }
3845 }
3846
3847 // Verify JNI static field identifiers
3848 if (jni_ids() != NULL) {
3849 jni_ids()->verify(this);
3850 }
3851
3852 // Verify other fields
3853 if (constants() != NULL) {
3854 guarantee(constants()->is_constantPool(), "should be constant pool");
3855 }
3856 }
3857
3858 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3859 Klass::oop_verify_on(obj, st);
3860 VerifyFieldClosure blk;
3861 obj->oop_iterate(&blk);
3862 }
3863
3864
3865 // JNIid class for jfieldIDs only
3866 // Note to reviewers:
3867 // These JNI functions are just moved over to column 1 and not changed
3868 // in the compressed oops workspace.
3869 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3870 _holder = holder;
3871 _offset = offset;
3872 _next = next;
3873 debug_only(_is_static_field_id = false;)
3874 }
3875
3876
3877 JNIid* JNIid::find(int offset) {
3878 JNIid* current = this;
3879 while (current != NULL) {
3880 if (current->offset() == offset) return current;
3881 current = current->next();
3882 }
3883 return NULL;
3884 }
3885
3886 void JNIid::deallocate(JNIid* current) {
3887 while (current != NULL) {
3888 JNIid* next = current->next();
3889 delete current;
3890 current = next;
3891 }
3892 }
3893
3894
3895 void JNIid::verify(Klass* holder) {
3896 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3897 int end_field_offset;
3898 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3899
3900 JNIid* current = this;
3901 while (current != NULL) {
3902 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3903 #ifdef ASSERT
3904 int o = current->offset();
3905 if (current->is_static_field_id()) {
3906 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3907 }
3908 #endif
3909 current = current->next();
3910 }
3911 }
3912
3913 void InstanceKlass::set_init_state(ClassState state) {
3914 #ifdef ASSERT
3915 bool good_state = is_shared() ? (_init_state <= state)
3916 : (_init_state < state);
3917 assert(good_state || state == allocated, "illegal state transition");
3918 #endif
3919 assert(_init_thread == NULL, "should be cleared before state change");
3920 _init_state = (u1)state;
3921 }
3922
3923 #if INCLUDE_JVMTI
3924
3925 // RedefineClasses() support for previous versions
3926
3927 // Globally, there is at least one previous version of a class to walk
3928 // during class unloading, which is saved because old methods in the class
3929 // are still running. Otherwise the previous version list is cleaned up.
3930 bool InstanceKlass::_has_previous_versions = false;
3931
3932 // Returns true if there are previous versions of a class for class
3933 // unloading only. Also resets the flag to false. purge_previous_version
3934 // will set the flag to true if there are any left, i.e., if there's any
3935 // work to do for next time. This is to avoid the expensive code cache
3936 // walk in CLDG::clean_deallocate_lists().
3937 bool InstanceKlass::has_previous_versions_and_reset() {
3938 bool ret = _has_previous_versions;
3939 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3940 ret ? "true" : "false");
3941 _has_previous_versions = false;
3942 return ret;
3943 }
3944
3945 // Purge previous versions before adding new previous versions of the class and
3946 // during class unloading.
3947 void InstanceKlass::purge_previous_version_list() {
3948 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3949 assert(has_been_redefined(), "Should only be called for main class");
3950
3951 // Quick exit.
3952 if (previous_versions() == NULL) {
3953 return;
3954 }
3955
3956 // This klass has previous versions so see what we can cleanup
3957 // while it is safe to do so.
3958
3959 int deleted_count = 0; // leave debugging breadcrumbs
3960 int live_count = 0;
3961 ClassLoaderData* loader_data = class_loader_data();
3962 assert(loader_data != NULL, "should never be null");
3963
3964 ResourceMark rm;
3965 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3966
3967 // previous versions are linked together through the InstanceKlass
3968 InstanceKlass* pv_node = previous_versions();
3969 InstanceKlass* last = this;
3970 int version = 0;
3971
3972 // check the previous versions list
3973 for (; pv_node != NULL; ) {
3974
3975 ConstantPool* pvcp = pv_node->constants();
3976 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3977
3978 if (!pvcp->on_stack()) {
3979 // If the constant pool isn't on stack, none of the methods
3980 // are executing. Unlink this previous_version.
3981 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3982 // so will be deallocated during the next phase of class unloading.
3983 log_trace(redefine, class, iklass, purge)
3984 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3985 // For debugging purposes.
3986 pv_node->set_is_scratch_class();
3987 // Unlink from previous version list.
3988 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3989 InstanceKlass* next = pv_node->previous_versions();
3990 pv_node->link_previous_versions(NULL); // point next to NULL
3991 last->link_previous_versions(next);
3992 // Delete this node directly. Nothing is referring to it and we don't
3993 // want it to increase the counter for metadata to delete in CLDG.
3994 MetadataFactory::free_metadata(loader_data, pv_node);
3995 pv_node = next;
3996 deleted_count++;
3997 version++;
3998 continue;
3999 } else {
4000 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
4001 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
4002 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4003 live_count++;
4004 // found a previous version for next time we do class unloading
4005 _has_previous_versions = true;
4006 }
4007
4008 // next previous version
4009 last = pv_node;
4010 pv_node = pv_node->previous_versions();
4011 version++;
4012 }
4013 log_trace(redefine, class, iklass, purge)
4014 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4015 }
4016
4017 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4018 int emcp_method_count) {
4019 int obsolete_method_count = old_methods->length() - emcp_method_count;
4020
4021 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4022 _previous_versions != NULL) {
4023 // We have a mix of obsolete and EMCP methods so we have to
4024 // clear out any matching EMCP method entries the hard way.
4025 int local_count = 0;
4026 for (int i = 0; i < old_methods->length(); i++) {
4027 Method* old_method = old_methods->at(i);
4028 if (old_method->is_obsolete()) {
4029 // only obsolete methods are interesting
4030 Symbol* m_name = old_method->name();
4031 Symbol* m_signature = old_method->signature();
4032
4033 // previous versions are linked together through the InstanceKlass
4034 int j = 0;
4035 for (InstanceKlass* prev_version = _previous_versions;
4036 prev_version != NULL;
4037 prev_version = prev_version->previous_versions(), j++) {
4038
4039 Array<Method*>* method_refs = prev_version->methods();
4040 for (int k = 0; k < method_refs->length(); k++) {
4041 Method* method = method_refs->at(k);
4042
4043 if (!method->is_obsolete() &&
4044 method->name() == m_name &&
4045 method->signature() == m_signature) {
4046 // The current RedefineClasses() call has made all EMCP
4047 // versions of this method obsolete so mark it as obsolete
4048 log_trace(redefine, class, iklass, add)
4049 ("%s(%s): flush obsolete method @%d in version @%d",
4050 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4051
4052 method->set_is_obsolete();
4053 break;
4054 }
4055 }
4056
4057 // The previous loop may not find a matching EMCP method, but
4058 // that doesn't mean that we can optimize and not go any
4059 // further back in the PreviousVersion generations. The EMCP
4060 // method for this generation could have already been made obsolete,
4061 // but there still may be an older EMCP method that has not
4062 // been made obsolete.
4063 }
4064
4065 if (++local_count >= obsolete_method_count) {
4066 // no more obsolete methods so bail out now
4067 break;
4068 }
4069 }
4070 }
4071 }
4072 }
4073
4074 // Save the scratch_class as the previous version if any of the methods are running.
4075 // The previous_versions are used to set breakpoints in EMCP methods and they are
4076 // also used to clean MethodData links to redefined methods that are no longer running.
4077 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4078 int emcp_method_count) {
4079 assert(Thread::current()->is_VM_thread(),
4080 "only VMThread can add previous versions");
4081
4082 ResourceMark rm;
4083 log_trace(redefine, class, iklass, add)
4084 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4085
4086 // Clean out old previous versions for this class
4087 purge_previous_version_list();
4088
4089 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4090 // a previous redefinition may be made obsolete by this redefinition.
4091 Array<Method*>* old_methods = scratch_class->methods();
4092 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4093
4094 // If the constant pool for this previous version of the class
4095 // is not marked as being on the stack, then none of the methods
4096 // in this previous version of the class are on the stack so
4097 // we don't need to add this as a previous version.
4098 ConstantPool* cp_ref = scratch_class->constants();
4099 if (!cp_ref->on_stack()) {
4100 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4101 // For debugging purposes.
4102 scratch_class->set_is_scratch_class();
4103 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4104 return;
4105 }
4106
4107 // Add previous version if any methods are still running.
4108 // Set has_previous_version flag for processing during class unloading.
4109 _has_previous_versions = true;
4110 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4111 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
4112 scratch_class->link_previous_versions(previous_versions());
4113 link_previous_versions(scratch_class);
4114 } // end add_previous_version()
4115
4116 #endif // INCLUDE_JVMTI
4117
4118 Method* InstanceKlass::method_with_idnum(int idnum) {
4119 Method* m = NULL;
4120 if (idnum < methods()->length()) {
4121 m = methods()->at(idnum);
4122 }
4123 if (m == NULL || m->method_idnum() != idnum) {
4124 for (int index = 0; index < methods()->length(); ++index) {
4125 m = methods()->at(index);
4126 if (m->method_idnum() == idnum) {
4127 return m;
4128 }
4129 }
4130 // None found, return null for the caller to handle.
4131 return NULL;
4132 }
4133 return m;
4134 }
4135
4136
4137 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4138 if (idnum >= methods()->length()) {
4139 return NULL;
4140 }
4141 Method* m = methods()->at(idnum);
4142 if (m != NULL && m->orig_method_idnum() == idnum) {
4143 return m;
4144 }
4145 // Obsolete method idnum does not match the original idnum
4146 for (int index = 0; index < methods()->length(); ++index) {
4147 m = methods()->at(index);
4148 if (m->orig_method_idnum() == idnum) {
4149 return m;
4150 }
4151 }
4152 // None found, return null for the caller to handle.
4153 return NULL;
4154 }
4155
4156
4157 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4158 InstanceKlass* holder = get_klass_version(version);
4159 if (holder == NULL) {
4160 return NULL; // The version of klass is gone, no method is found
4161 }
4162 Method* method = holder->method_with_orig_idnum(idnum);
4163 return method;
4164 }
4165
4166 #if INCLUDE_JVMTI
4167 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4168 return _cached_class_file;
4169 }
4170
4171 jint InstanceKlass::get_cached_class_file_len() {
4172 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4173 }
4174
4175 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4176 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4177 }
4178 #endif
4179
4180 // Make a step iterating over the class hierarchy under the root class.
4181 // Skips subclasses if requested.
4182 void ClassHierarchyIterator::next() {
4183 assert(_current != NULL, "required");
4184 if (_visit_subclasses && _current->subklass() != NULL) {
4185 _current = _current->subklass();
4186 return; // visit next subclass
4187 }
4188 _visit_subclasses = true; // reset
4189 while (_current->next_sibling() == NULL && _current != _root) {
4190 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4191 }
4192 if (_current == _root) {
4193 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4194 _current = NULL;
4195 return;
4196 }
4197 _current = _current->next_sibling();
4198 return; // visit next sibling subclass
4199 }