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