1 /*
2 * Copyright (c) 1997, 2020, 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 "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/symbolTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "classfile/verifier.hpp"
38 #include "classfile/vmSymbols.hpp"
39 #include "code/dependencyContext.hpp"
40 #include "compiler/compileBroker.hpp"
41 #include "gc/shared/collectedHeap.inline.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "interpreter/rewriter.hpp"
44 #include "jvmtifiles/jvmti.h"
45 #include "logging/log.hpp"
46 #include "logging/logMessage.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.hpp"
49 #include "memory/iterator.inline.hpp"
50 #include "memory/metadataFactory.hpp"
51 #include "memory/metaspaceClosure.hpp"
52 #include "memory/metaspaceShared.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "memory/universe.hpp"
56 #include "oops/fieldStreams.inline.hpp"
57 #include "oops/constantPool.hpp"
58 #include "oops/instanceClassLoaderKlass.hpp"
59 #include "oops/instanceKlass.inline.hpp"
60 #include "oops/instanceMirrorKlass.hpp"
61 #include "oops/instanceOop.hpp"
62 #include "oops/klass.inline.hpp"
63 #include "oops/method.hpp"
64 #include "oops/oop.inline.hpp"
65 #include "oops/recordComponent.hpp"
66 #include "oops/symbol.hpp"
67 #include "prims/jvmtiExport.hpp"
68 #include "prims/jvmtiRedefineClasses.hpp"
69 #include "prims/jvmtiThreadState.hpp"
70 #include "prims/methodComparator.hpp"
71 #include "runtime/atomic.hpp"
72 #include "runtime/biasedLocking.hpp"
73 #include "runtime/fieldDescriptor.inline.hpp"
74 #include "runtime/handles.inline.hpp"
75 #include "runtime/javaCalls.hpp"
76 #include "runtime/mutexLocker.hpp"
77 #include "runtime/orderAccess.hpp"
78 #include "runtime/thread.inline.hpp"
79 #include "services/classLoadingService.hpp"
80 #include "services/threadService.hpp"
81 #include "utilities/dtrace.hpp"
82 #include "utilities/events.hpp"
83 #include "utilities/macros.hpp"
84 #include "utilities/stringUtils.hpp"
85 #ifdef COMPILER1
86 #include "c1/c1_Compiler.hpp"
87 #endif
88 #if INCLUDE_JFR
89 #include "jfr/jfrEvents.hpp"
90 #endif
91
92
93 #ifdef DTRACE_ENABLED
94
95
96 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
97 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
98 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
99 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
100 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
101 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
102 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
103 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
104 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
105 { \
106 char* data = NULL; \
107 int len = 0; \
108 Symbol* clss_name = name(); \
109 if (clss_name != NULL) { \
110 data = (char*)clss_name->bytes(); \
111 len = clss_name->utf8_length(); \
112 } \
113 HOTSPOT_CLASS_INITIALIZATION_##type( \
114 data, len, (void*)class_loader(), thread_type); \
115 }
116
117 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
118 { \
119 char* data = NULL; \
120 int len = 0; \
121 Symbol* clss_name = name(); \
122 if (clss_name != NULL) { \
123 data = (char*)clss_name->bytes(); \
124 len = clss_name->utf8_length(); \
125 } \
126 HOTSPOT_CLASS_INITIALIZATION_##type( \
127 data, len, (void*)class_loader(), thread_type, wait); \
128 }
129
130 #else // ndef DTRACE_ENABLED
131
132 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
134
135 #endif // ndef DTRACE_ENABLED
136
137 static inline bool is_class_loader(const Symbol* class_name,
138 const ClassFileParser& parser) {
139 assert(class_name != NULL, "invariant");
140
141 if (class_name == vmSymbols::java_lang_ClassLoader()) {
142 return true;
143 }
144
145 if (SystemDictionary::ClassLoader_klass_loaded()) {
146 const Klass* const super_klass = parser.super_klass();
147 if (super_klass != NULL) {
148 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
149 return true;
150 }
151 }
152 }
153 return false;
154 }
155
156 // private: called to verify that k is a static member of this nest.
157 // We know that k is an instance class in the same package and hence the
158 // same classloader.
159 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
160 assert(!is_hidden(), "unexpected hidden class");
161 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
162 if (log_is_enabled(Trace, class, nestmates)) {
163 ResourceMark rm(THREAD);
164 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
165 k->external_name(), this->external_name());
166 }
167 return false;
168 }
169
170 if (log_is_enabled(Trace, class, nestmates)) {
171 ResourceMark rm(THREAD);
172 log_trace(class, nestmates)("Checking nest membership of %s in %s",
173 k->external_name(), this->external_name());
174 }
175
176 // Check for a resolved cp entry , else fall back to a name check.
177 // We don't want to resolve any class other than the one being checked.
178 for (int i = 0; i < _nest_members->length(); i++) {
179 int cp_index = _nest_members->at(i);
180 if (_constants->tag_at(cp_index).is_klass()) {
181 Klass* k2 = _constants->klass_at(cp_index, THREAD);
182 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()),
183 "Exceptions should not be possible here");
184 if (k2 == k) {
185 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
186 return true;
187 }
188 }
189 else {
190 Symbol* name = _constants->klass_name_at(cp_index);
191 if (name == k->name()) {
192 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
193
194 // Names match so check actual klass. This may trigger class loading if
195 // it doesn't match though that should be impossible as it means one classloader
196 // has defined two different classes with the same name! A compiler thread won't be
197 // able to perform that loading but we can't exclude the compiler threads from
198 // executing this logic. But it should actually be impossible to trigger loading here.
199 Klass* k2 = _constants->klass_at(cp_index, THREAD);
200 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()),
201 "Exceptions should not be possible here");
202 if (k2 == k) {
203 log_trace(class, nestmates)("- class is listed as a nest member");
204 return true;
205 }
206 else {
207 // same name but different klass!
208 log_trace(class, nestmates)(" - klass comparison failed!");
209 // can't have two names the same, so we're done
210 return false;
211 }
212 }
213 }
214 }
215 log_trace(class, nestmates)("- class is NOT a nest member!");
216 return false;
217 }
218
219 // Return nest-host class, resolving, validating and saving it if needed.
220 // In cases where this is called from a thread that cannot do classloading
221 // (such as a native JIT thread) then we simply return NULL, which in turn
222 // causes the access check to return false. Such code will retry the access
223 // from a more suitable environment later. Otherwise the _nest_host is always
224 // set once this method returns.
225 // Any errors from nest-host resolution must be preserved so they can be queried
226 // from higher-level access checking code, and reported as part of access checking
227 // exceptions.
228 // VirtualMachineErrors are propagated with a NULL return.
229 // Under any conditions where the _nest_host can be set to non-NULL the resulting value
230 // of it and, if applicable, _nest_host_res_error, are idempotent. But as we can be
231 // executing this code concurrently we need to ensure ordering is maintained so that
232 // errors messages can safely be read.
233 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
234 InstanceKlass* nest_host_k = _nest_host;
235 if (nest_host_k != NULL) {
236 return nest_host_k;
237 }
238
239 ResourceMark rm(THREAD);
240
241 // need to resolve and save our nest-host class.
242 if (_nest_host_index != 0) { // we have a real nest_host
243 // Before trying to resolve check if we're in a suitable context
244 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
245 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
246 this->external_name());
247 return NULL; // sentinel to say "try again from a different context"
248 }
249
250 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
251 this->external_name(),
252 _constants->klass_name_at(_nest_host_index)->as_C_string());
253
254 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
255 if (HAS_PENDING_EXCEPTION) {
256 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) {
257 return NULL; // propagate VMEs
258 }
259 stringStream ss;
260 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
261 ss.print("Nest host resolution of %s with host %s failed: ",
262 this->external_name(), target_host_class);
263 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
264 _nest_host_res_error = ss.as_string(true /* on C-heap */);
265 // ensure we see _nest_host_res_error is set if _nest_host is non-NULL
266 OrderAccess::storestore();
267 CLEAR_PENDING_EXCEPTION;
268
269 log_trace(class, nestmates)("%s", _nest_host_res_error);
270 } else {
271 // A valid nest-host is an instance class in the current package that lists this
272 // class as a nest member. If any of these conditions are not met the class is
273 // its own nest-host.
274 const char* error = NULL;
275
276 // JVMS 5.4.4 indicates package check comes first
277 if (is_same_class_package(k)) {
278 // Now check actual membership. We can't be a member if our "host" is
279 // not an instance class.
280 if (k->is_instance_klass()) {
281 nest_host_k = InstanceKlass::cast(k);
282 bool is_member = nest_host_k->has_nest_member(this, THREAD);
283 // exception is rare, perhaps impossible
284 if (!HAS_PENDING_EXCEPTION) {
285 if (is_member) {
286 _nest_host = nest_host_k; // save resolved nest-host value
287
288 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
289 this->external_name(), k->external_name());
290 return nest_host_k;
291 } else {
292 error = "current type is not listed as a nest member";
293 }
294 } else {
295 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) {
296 return NULL; // propagate VMEs
297 }
298 stringStream ss;
299 ss.print("exception on member check: ");
300 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
301 error = ss.as_string();
302 }
303 } else {
304 error = "host is not an instance class";
305 }
306 } else {
307 error = "types are in different packages";
308 }
309
310 // something went wrong, so record what and log it
311 {
312 stringStream ss;
313 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
314 this->external_name(),
315 this->class_loader_data()->loader_name_and_id(),
316 k->external_name(),
317 k->class_loader_data()->loader_name_and_id(),
318 error);
319 _nest_host_res_error = ss.as_string(true /* on C-heap */);
320 // ensure we see _nest_host_res_error is set if _nest_host is non-NULL
321 OrderAccess::storestore();
322
323 log_trace(class, nestmates)("%s", _nest_host_res_error);
324 }
325 }
326 } else {
327 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
328 this->external_name());
329 }
330
331 // Either not in an explicit nest, or else an error occurred, so
332 // the nest-host is set to `this`. Any thread that sees this assignment
333 // will also see any setting of _nest_host_res_error, if applicable.
334 return (_nest_host = this);
335 }
336
337 // Dynamic nest member support: set this class's nest host to the given class.
338 // This occurs as part of the class definition, as soon as the instanceKlass
339 // has been created and doesn't require further resolution. The code:
340 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
341 // results in:
342 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
343 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
344 // We also know the "host" is a valid nest-host in the same package so we can
345 // assert some of those facts.
346 void InstanceKlass::set_nest_host(InstanceKlass* host, TRAPS) {
347 assert(is_hidden(), "must be a hidden class");
348 assert(host != NULL, "NULL nest host specified");
349 assert(_nest_host == NULL, "current class has resolved nest-host");
350 assert(_nest_host_res_error == NULL, "unexpected nest host resolution error exists: %s",
351 _nest_host_res_error);
352 assert((host->_nest_host == NULL && host->_nest_host_index == 0) ||
353 (host->_nest_host == host), "proposed host is not a valid nest-host");
354 // Can't assert this as package is not set yet:
355 // assert(is_same_class_package(host), "proposed host is in wrong package");
356
357 if (log_is_enabled(Trace, class, nestmates)) {
358 ResourceMark rm(THREAD);
359 const char* msg = "";
360 // a hidden class does not expect a statically defined nest-host
361 if (_nest_host_index > 0) {
362 msg = "(the NestHost attribute in the current class is ignored)";
363 } else if (_nest_members != NULL && _nest_members != Universe::the_empty_short_array()) {
364 msg = "(the NestMembers attribute in the current class is ignored)";
365 }
366 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
367 this->external_name(),
368 host->external_name(),
369 msg);
370 }
371 // set dynamic nest host
372 _nest_host = host;
373 }
374
375 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
376 // or we are k's nest_host - all of which is covered by comparing the two
377 // resolved_nest_hosts.
378 // Any exceptions (i.e. VMEs) are propagated.
379 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
380
381 assert(this != k, "this should be handled by higher-level code");
382
383 // Per JVMS 5.4.4 we first resolve and validate the current class, then
384 // the target class k.
385
386 InstanceKlass* cur_host = nest_host(CHECK_false);
387 if (cur_host == NULL) {
388 return false;
389 }
390
391 Klass* k_nest_host = k->nest_host(CHECK_false);
392 if (k_nest_host == NULL) {
393 return false;
394 }
395
396 bool access = (cur_host == k_nest_host);
397
398 ResourceMark rm(THREAD);
399 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
400 this->external_name(),
401 access ? "" : "NOT ",
402 k->external_name());
403 return access;
404 }
405
406 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
407 bool is_hidden_or_anonymous = parser.is_hidden() || parser.is_unsafe_anonymous();
408 const int size = InstanceKlass::size(parser.vtable_size(),
409 parser.itable_size(),
410 nonstatic_oop_map_size(parser.total_oop_map_count()),
411 parser.is_interface(),
412 is_hidden_or_anonymous,
413 should_store_fingerprint(is_hidden_or_anonymous));
414
415 const Symbol* const class_name = parser.class_name();
416 assert(class_name != NULL, "invariant");
417 ClassLoaderData* loader_data = parser.loader_data();
418 assert(loader_data != NULL, "invariant");
419
420 InstanceKlass* ik;
421
422 // Allocation
423 if (REF_NONE == parser.reference_type()) {
424 if (class_name == vmSymbols::java_lang_Class()) {
425 // mirror
426 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
427 }
428 else if (is_class_loader(class_name, parser)) {
429 // class loader
430 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
431 } else {
432 // normal
433 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
434 }
435 } else {
436 // reference
437 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
438 }
439
440 // Check for pending exception before adding to the loader data and incrementing
441 // class count. Can get OOM here.
442 if (HAS_PENDING_EXCEPTION) {
443 return NULL;
444 }
445
446 return ik;
447 }
448
449
450 // copy method ordering from resource area to Metaspace
451 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
452 if (m != NULL) {
453 // allocate a new array and copy contents (memcpy?)
454 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
455 for (int i = 0; i < m->length(); i++) {
456 _method_ordering->at_put(i, m->at(i));
457 }
458 } else {
459 _method_ordering = Universe::the_empty_int_array();
460 }
461 }
462
463 // create a new array of vtable_indices for default methods
464 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
465 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
466 assert(default_vtable_indices() == NULL, "only create once");
467 set_default_vtable_indices(vtable_indices);
468 return vtable_indices;
469 }
470
471 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
472 Klass(id),
473 _nest_members(NULL),
474 _nest_host_index(0),
475 _nest_host(NULL),
476 _nest_host_res_error(NULL),
477 _record_components(NULL),
478 _static_field_size(parser.static_field_size()),
479 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
480 _itable_len(parser.itable_size()),
481 _init_thread(NULL),
482 _init_state(allocated),
483 _reference_type(parser.reference_type())
484 {
485 set_vtable_length(parser.vtable_size());
486 set_kind(kind);
487 set_access_flags(parser.access_flags());
488 if (parser.is_hidden()) set_is_hidden();
489 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
490 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
491 false));
492
493 assert(NULL == _methods, "underlying memory not zeroed?");
494 assert(is_instance_klass(), "is layout incorrect?");
495 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
496
497 if (Arguments::is_dumping_archive()) {
498 SystemDictionaryShared::init_dumptime_info(this);
499 }
500
501 // Set biased locking bit for all instances of this class; it will be
502 // cleared if revocation occurs too often for this type
503 if (UseBiasedLocking && BiasedLocking::enabled()) {
504 set_prototype_header(markWord::biased_locking_prototype());
505 }
506 }
507
508 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
509 Array<Method*>* methods) {
510 if (methods != NULL && methods != Universe::the_empty_method_array() &&
511 !methods->is_shared()) {
512 for (int i = 0; i < methods->length(); i++) {
513 Method* method = methods->at(i);
514 if (method == NULL) continue; // maybe null if error processing
515 // Only want to delete methods that are not executing for RedefineClasses.
516 // The previous version will point to them so they're not totally dangling
517 assert (!method->on_stack(), "shouldn't be called with methods on stack");
518 MetadataFactory::free_metadata(loader_data, method);
519 }
520 MetadataFactory::free_array<Method*>(loader_data, methods);
521 }
522 }
523
524 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
525 const Klass* super_klass,
526 Array<InstanceKlass*>* local_interfaces,
527 Array<InstanceKlass*>* transitive_interfaces) {
528 // Only deallocate transitive interfaces if not empty, same as super class
529 // or same as local interfaces. See code in parseClassFile.
530 Array<InstanceKlass*>* ti = transitive_interfaces;
531 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
532 // check that the interfaces don't come from super class
533 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
534 InstanceKlass::cast(super_klass)->transitive_interfaces();
535 if (ti != sti && ti != NULL && !ti->is_shared()) {
536 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
537 }
538 }
539
540 // local interfaces can be empty
541 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
542 local_interfaces != NULL && !local_interfaces->is_shared()) {
543 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
544 }
545 }
546
547 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
548 Array<RecordComponent*>* record_components) {
549 if (record_components != NULL && !record_components->is_shared()) {
550 for (int i = 0; i < record_components->length(); i++) {
551 RecordComponent* record_component = record_components->at(i);
552 MetadataFactory::free_metadata(loader_data, record_component);
553 }
554 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
555 }
556 }
557
558 // This function deallocates the metadata and C heap pointers that the
559 // InstanceKlass points to.
560 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
561
562 // Orphan the mirror first, CMS thinks it's still live.
563 if (java_mirror() != NULL) {
564 java_lang_Class::set_klass(java_mirror(), NULL);
565 }
566
567 // Also remove mirror from handles
568 loader_data->remove_handle(_java_mirror);
569
570 // Need to take this class off the class loader data list.
571 loader_data->remove_class(this);
572
573 // The array_klass for this class is created later, after error handling.
574 // For class redefinition, we keep the original class so this scratch class
575 // doesn't have an array class. Either way, assert that there is nothing
576 // to deallocate.
577 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
578
579 // Release C heap allocated data that this might point to, which includes
580 // reference counting symbol names.
581 release_C_heap_structures();
582
583 deallocate_methods(loader_data, methods());
584 set_methods(NULL);
585
586 deallocate_record_components(loader_data, record_components());
587 set_record_components(NULL);
588
589 if (method_ordering() != NULL &&
590 method_ordering() != Universe::the_empty_int_array() &&
591 !method_ordering()->is_shared()) {
592 MetadataFactory::free_array<int>(loader_data, method_ordering());
593 }
594 set_method_ordering(NULL);
595
596 // default methods can be empty
597 if (default_methods() != NULL &&
598 default_methods() != Universe::the_empty_method_array() &&
599 !default_methods()->is_shared()) {
600 MetadataFactory::free_array<Method*>(loader_data, default_methods());
601 }
602 // Do NOT deallocate the default methods, they are owned by superinterfaces.
603 set_default_methods(NULL);
604
605 // default methods vtable indices can be empty
606 if (default_vtable_indices() != NULL &&
607 !default_vtable_indices()->is_shared()) {
608 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
609 }
610 set_default_vtable_indices(NULL);
611
612
613 // This array is in Klass, but remove it with the InstanceKlass since
614 // this place would be the only caller and it can share memory with transitive
615 // interfaces.
616 if (secondary_supers() != NULL &&
617 secondary_supers() != Universe::the_empty_klass_array() &&
618 // see comments in compute_secondary_supers about the following cast
619 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
620 !secondary_supers()->is_shared()) {
621 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
622 }
623 set_secondary_supers(NULL);
624
625 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
626 set_transitive_interfaces(NULL);
627 set_local_interfaces(NULL);
628
629 if (fields() != NULL && !fields()->is_shared()) {
630 MetadataFactory::free_array<jushort>(loader_data, fields());
631 }
632 set_fields(NULL, 0);
633
634 // If a method from a redefined class is using this constant pool, don't
635 // delete it, yet. The new class's previous version will point to this.
636 if (constants() != NULL) {
637 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
638 if (!constants()->is_shared()) {
639 MetadataFactory::free_metadata(loader_data, constants());
640 }
641 // Delete any cached resolution errors for the constant pool
642 SystemDictionary::delete_resolution_error(constants());
643
644 set_constants(NULL);
645 }
646
647 if (inner_classes() != NULL &&
648 inner_classes() != Universe::the_empty_short_array() &&
649 !inner_classes()->is_shared()) {
650 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
651 }
652 set_inner_classes(NULL);
653
654 if (nest_members() != NULL &&
655 nest_members() != Universe::the_empty_short_array() &&
656 !nest_members()->is_shared()) {
657 MetadataFactory::free_array<jushort>(loader_data, nest_members());
658 }
659 set_nest_members(NULL);
660
661 // We should deallocate the Annotations instance if it's not in shared spaces.
662 if (annotations() != NULL && !annotations()->is_shared()) {
663 MetadataFactory::free_metadata(loader_data, annotations());
664 }
665 set_annotations(NULL);
666
667 if (Arguments::is_dumping_archive()) {
668 SystemDictionaryShared::remove_dumptime_info(this);
669 }
670 }
671
672 bool InstanceKlass::should_be_initialized() const {
673 return !is_initialized();
674 }
675
676 klassItable InstanceKlass::itable() const {
677 return klassItable(const_cast<InstanceKlass*>(this));
678 }
679
680 void InstanceKlass::eager_initialize(Thread *thread) {
681 if (!EagerInitialization) return;
682
683 if (this->is_not_initialized()) {
684 // abort if the the class has a class initializer
685 if (this->class_initializer() != NULL) return;
686
687 // abort if it is java.lang.Object (initialization is handled in genesis)
688 Klass* super_klass = super();
689 if (super_klass == NULL) return;
690
691 // abort if the super class should be initialized
692 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
693
694 // call body to expose the this pointer
695 eager_initialize_impl();
696 }
697 }
698
699 // JVMTI spec thinks there are signers and protection domain in the
700 // instanceKlass. These accessors pretend these fields are there.
701 // The hprof specification also thinks these fields are in InstanceKlass.
702 oop InstanceKlass::protection_domain() const {
703 // return the protection_domain from the mirror
704 return java_lang_Class::protection_domain(java_mirror());
705 }
706
707 // To remove these from requires an incompatible change and CCC request.
708 objArrayOop InstanceKlass::signers() const {
709 // return the signers from the mirror
710 return java_lang_Class::signers(java_mirror());
711 }
712
713 oop InstanceKlass::init_lock() const {
714 // return the init lock from the mirror
715 oop lock = java_lang_Class::init_lock(java_mirror());
716 // Prevent reordering with any access of initialization state
717 OrderAccess::loadload();
718 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
719 "only fully initialized state can have a null lock");
720 return lock;
721 }
722
723 // Set the initialization lock to null so the object can be GC'ed. Any racing
724 // threads to get this lock will see a null lock and will not lock.
725 // That's okay because they all check for initialized state after getting
726 // the lock and return.
727 void InstanceKlass::fence_and_clear_init_lock() {
728 // make sure previous stores are all done, notably the init_state.
729 OrderAccess::storestore();
730 java_lang_Class::set_init_lock(java_mirror(), NULL);
731 assert(!is_not_initialized(), "class must be initialized now");
732 }
733
734 void InstanceKlass::eager_initialize_impl() {
735 EXCEPTION_MARK;
736 HandleMark hm(THREAD);
737 Handle h_init_lock(THREAD, init_lock());
738 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
739
740 // abort if someone beat us to the initialization
741 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
742
743 ClassState old_state = init_state();
744 link_class_impl(THREAD);
745 if (HAS_PENDING_EXCEPTION) {
746 CLEAR_PENDING_EXCEPTION;
747 // Abort if linking the class throws an exception.
748
749 // Use a test to avoid redundantly resetting the state if there's
750 // no change. Set_init_state() asserts that state changes make
751 // progress, whereas here we might just be spinning in place.
752 if (old_state != _init_state)
753 set_init_state(old_state);
754 } else {
755 // linking successfull, mark class as initialized
756 set_init_state(fully_initialized);
757 fence_and_clear_init_lock();
758 // trace
759 if (log_is_enabled(Info, class, init)) {
760 ResourceMark rm(THREAD);
761 log_info(class, init)("[Initialized %s without side effects]", external_name());
762 }
763 }
764 }
765
766
767 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
768 // process. The step comments refers to the procedure described in that section.
769 // Note: implementation moved to static method to expose the this pointer.
770 void InstanceKlass::initialize(TRAPS) {
771 if (this->should_be_initialized()) {
772 initialize_impl(CHECK);
773 // Note: at this point the class may be initialized
774 // OR it may be in the state of being initialized
775 // in case of recursive initialization!
776 } else {
777 assert(is_initialized(), "sanity check");
778 }
779 }
780
781
782 bool InstanceKlass::verify_code(TRAPS) {
783 // 1) Verify the bytecodes
784 return Verifier::verify(this, should_verify_class(), THREAD);
785 }
786
787 void InstanceKlass::link_class(TRAPS) {
788 assert(is_loaded(), "must be loaded");
789 if (!is_linked()) {
790 link_class_impl(CHECK);
791 }
792 }
793
794 // Called to verify that a class can link during initialization, without
795 // throwing a VerifyError.
796 bool InstanceKlass::link_class_or_fail(TRAPS) {
797 assert(is_loaded(), "must be loaded");
798 if (!is_linked()) {
799 link_class_impl(CHECK_false);
800 }
801 return is_linked();
802 }
803
804 bool InstanceKlass::link_class_impl(TRAPS) {
805 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
806 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
807 // the class has failed verification. Throwing the NoClassDefFoundError here is just
808 // a convenient way to stop repeat attempts to verify the same (bad) class.
809 //
810 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
811 // if we are executing Java code. This is not a problem for CDS dumping phase since
812 // it doesn't execute any Java code.
813 ResourceMark rm(THREAD);
814 Exceptions::fthrow(THREAD_AND_LOCATION,
815 vmSymbols::java_lang_NoClassDefFoundError(),
816 "Class %s, or one of its supertypes, failed class initialization",
817 external_name());
818 return false;
819 }
820 // return if already verified
821 if (is_linked()) {
822 return true;
823 }
824
825 // Timing
826 // timer handles recursion
827 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
828 JavaThread* jt = (JavaThread*)THREAD;
829
830 // link super class before linking this class
831 Klass* super_klass = super();
832 if (super_klass != NULL) {
833 if (super_klass->is_interface()) { // check if super class is an interface
834 ResourceMark rm(THREAD);
835 Exceptions::fthrow(
836 THREAD_AND_LOCATION,
837 vmSymbols::java_lang_IncompatibleClassChangeError(),
838 "class %s has interface %s as super class",
839 external_name(),
840 super_klass->external_name()
841 );
842 return false;
843 }
844
845 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
846 ik_super->link_class_impl(CHECK_false);
847 }
848
849 // link all interfaces implemented by this class before linking this class
850 Array<InstanceKlass*>* interfaces = local_interfaces();
851 int num_interfaces = interfaces->length();
852 for (int index = 0; index < num_interfaces; index++) {
853 InstanceKlass* interk = interfaces->at(index);
854 interk->link_class_impl(CHECK_false);
855 }
856
857 // in case the class is linked in the process of linking its superclasses
858 if (is_linked()) {
859 return true;
860 }
861
862 // trace only the link time for this klass that includes
863 // the verification time
864 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
865 ClassLoader::perf_class_link_selftime(),
866 ClassLoader::perf_classes_linked(),
867 jt->get_thread_stat()->perf_recursion_counts_addr(),
868 jt->get_thread_stat()->perf_timers_addr(),
869 PerfClassTraceTime::CLASS_LINK);
870
871 // verification & rewriting
872 {
873 HandleMark hm(THREAD);
874 Handle h_init_lock(THREAD, init_lock());
875 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
876 // rewritten will have been set if loader constraint error found
877 // on an earlier link attempt
878 // don't verify or rewrite if already rewritten
879 //
880
881 if (!is_linked()) {
882 if (!is_rewritten()) {
883 {
884 bool verify_ok = verify_code(THREAD);
885 if (!verify_ok) {
886 return false;
887 }
888 }
889
890 // Just in case a side-effect of verify linked this class already
891 // (which can sometimes happen since the verifier loads classes
892 // using custom class loaders, which are free to initialize things)
893 if (is_linked()) {
894 return true;
895 }
896
897 // also sets rewritten
898 rewrite_class(CHECK_false);
899 } else if (is_shared()) {
900 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
901 }
902
903 // relocate jsrs and link methods after they are all rewritten
904 link_methods(CHECK_false);
905
906 // Initialize the vtable and interface table after
907 // methods have been rewritten since rewrite may
908 // fabricate new Method*s.
909 // also does loader constraint checking
910 //
911 // initialize_vtable and initialize_itable need to be rerun for
912 // a shared class if the class is not loaded by the NULL classloader.
913 ClassLoaderData * loader_data = class_loader_data();
914 if (!(is_shared() &&
915 loader_data->is_the_null_class_loader_data())) {
916 vtable().initialize_vtable(true, CHECK_false);
917 itable().initialize_itable(true, CHECK_false);
918 }
919 #ifdef ASSERT
920 else {
921 vtable().verify(tty, true);
922 // In case itable verification is ever added.
923 // itable().verify(tty, true);
924 }
925 #endif
926 set_init_state(linked);
927 if (JvmtiExport::should_post_class_prepare()) {
928 Thread *thread = THREAD;
929 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
930 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
931 }
932 }
933 }
934 return true;
935 }
936
937 // Rewrite the byte codes of all of the methods of a class.
938 // The rewriter must be called exactly once. Rewriting must happen after
939 // verification but before the first method of the class is executed.
940 void InstanceKlass::rewrite_class(TRAPS) {
941 assert(is_loaded(), "must be loaded");
942 if (is_rewritten()) {
943 assert(is_shared(), "rewriting an unshared class?");
944 return;
945 }
946 Rewriter::rewrite(this, CHECK);
947 set_rewritten();
948 }
949
950 // Now relocate and link method entry points after class is rewritten.
951 // This is outside is_rewritten flag. In case of an exception, it can be
952 // executed more than once.
953 void InstanceKlass::link_methods(TRAPS) {
954 int len = methods()->length();
955 for (int i = len-1; i >= 0; i--) {
956 methodHandle m(THREAD, methods()->at(i));
957
958 // Set up method entry points for compiler and interpreter .
959 m->link_method(m, CHECK);
960 }
961 }
962
963 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
964 void InstanceKlass::initialize_super_interfaces(TRAPS) {
965 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
966 for (int i = 0; i < local_interfaces()->length(); ++i) {
967 InstanceKlass* ik = local_interfaces()->at(i);
968
969 // Initialization is depth first search ie. we start with top of the inheritance tree
970 // has_nonstatic_concrete_methods drives searching superinterfaces since it
971 // means has_nonstatic_concrete_methods in its superinterface hierarchy
972 if (ik->has_nonstatic_concrete_methods()) {
973 ik->initialize_super_interfaces(CHECK);
974 }
975
976 // Only initialize() interfaces that "declare" concrete methods.
977 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
978 ik->initialize(CHECK);
979 }
980 }
981 }
982
983 void InstanceKlass::initialize_impl(TRAPS) {
984 HandleMark hm(THREAD);
985
986 // Make sure klass is linked (verified) before initialization
987 // A class could already be verified, since it has been reflected upon.
988 link_class(CHECK);
989
990 DTRACE_CLASSINIT_PROBE(required, -1);
991
992 bool wait = false;
993
994 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
995 JavaThread* jt = (JavaThread*)THREAD;
996
997 // refer to the JVM book page 47 for description of steps
998 // Step 1
999 {
1000 Handle h_init_lock(THREAD, init_lock());
1001 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
1002
1003 // Step 2
1004 // If we were to use wait() instead of waitInterruptibly() then
1005 // we might end up throwing IE from link/symbol resolution sites
1006 // that aren't expected to throw. This would wreak havoc. See 6320309.
1007 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1008 wait = true;
1009 jt->set_class_to_be_initialized(this);
1010 ol.wait_uninterruptibly(jt);
1011 jt->set_class_to_be_initialized(NULL);
1012 }
1013
1014 // Step 3
1015 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1016 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1017 return;
1018 }
1019
1020 // Step 4
1021 if (is_initialized()) {
1022 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1023 return;
1024 }
1025
1026 // Step 5
1027 if (is_in_error_state()) {
1028 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1029 ResourceMark rm(THREAD);
1030 const char* desc = "Could not initialize class ";
1031 const char* className = external_name();
1032 size_t msglen = strlen(desc) + strlen(className) + 1;
1033 char* message = NEW_RESOURCE_ARRAY(char, msglen);
1034 if (NULL == message) {
1035 // Out of memory: can't create detailed error message
1036 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
1037 } else {
1038 jio_snprintf(message, msglen, "%s%s", desc, className);
1039 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
1040 }
1041 }
1042
1043 // Step 6
1044 set_init_state(being_initialized);
1045 set_init_thread(jt);
1046 }
1047
1048 // Step 7
1049 // Next, if C is a class rather than an interface, initialize it's super class and super
1050 // interfaces.
1051 if (!is_interface()) {
1052 Klass* super_klass = super();
1053 if (super_klass != NULL && super_klass->should_be_initialized()) {
1054 super_klass->initialize(THREAD);
1055 }
1056 // If C implements any interface that declares a non-static, concrete method,
1057 // the initialization of C triggers initialization of its super interfaces.
1058 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1059 // having a superinterface that declares, non-static, concrete methods
1060 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1061 initialize_super_interfaces(THREAD);
1062 }
1063
1064 // If any exceptions, complete abruptly, throwing the same exception as above.
1065 if (HAS_PENDING_EXCEPTION) {
1066 Handle e(THREAD, PENDING_EXCEPTION);
1067 CLEAR_PENDING_EXCEPTION;
1068 {
1069 EXCEPTION_MARK;
1070 // Locks object, set state, and notify all waiting threads
1071 set_initialization_state_and_notify(initialization_error, THREAD);
1072 CLEAR_PENDING_EXCEPTION;
1073 }
1074 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1075 THROW_OOP(e());
1076 }
1077 }
1078
1079
1080 // Look for aot compiled methods for this klass, including class initializer.
1081 AOTLoader::load_for_klass(this, THREAD);
1082
1083 // Step 8
1084 {
1085 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1086 // Timer includes any side effects of class initialization (resolution,
1087 // etc), but not recursive entry into call_class_initializer().
1088 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1089 ClassLoader::perf_class_init_selftime(),
1090 ClassLoader::perf_classes_inited(),
1091 jt->get_thread_stat()->perf_recursion_counts_addr(),
1092 jt->get_thread_stat()->perf_timers_addr(),
1093 PerfClassTraceTime::CLASS_CLINIT);
1094 call_class_initializer(THREAD);
1095 }
1096
1097 // Step 9
1098 if (!HAS_PENDING_EXCEPTION) {
1099 set_initialization_state_and_notify(fully_initialized, CHECK);
1100 {
1101 debug_only(vtable().verify(tty, true);)
1102 }
1103 }
1104 else {
1105 // Step 10 and 11
1106 Handle e(THREAD, PENDING_EXCEPTION);
1107 CLEAR_PENDING_EXCEPTION;
1108 // JVMTI has already reported the pending exception
1109 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1110 JvmtiExport::clear_detected_exception(jt);
1111 {
1112 EXCEPTION_MARK;
1113 set_initialization_state_and_notify(initialization_error, THREAD);
1114 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1115 // JVMTI has already reported the pending exception
1116 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1117 JvmtiExport::clear_detected_exception(jt);
1118 }
1119 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1120 if (e->is_a(SystemDictionary::Error_klass())) {
1121 THROW_OOP(e());
1122 } else {
1123 JavaCallArguments args(e);
1124 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1125 vmSymbols::throwable_void_signature(),
1126 &args);
1127 }
1128 }
1129 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1130 }
1131
1132
1133 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1134 Handle h_init_lock(THREAD, init_lock());
1135 if (h_init_lock() != NULL) {
1136 ObjectLocker ol(h_init_lock, THREAD);
1137 set_init_thread(NULL); // reset _init_thread before changing _init_state
1138 set_init_state(state);
1139 fence_and_clear_init_lock();
1140 ol.notify_all(CHECK);
1141 } else {
1142 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1143 set_init_thread(NULL); // reset _init_thread before changing _init_state
1144 set_init_state(state);
1145 }
1146 }
1147
1148 Klass* InstanceKlass::implementor() const {
1149 Klass* volatile* k = adr_implementor();
1150 if (k == NULL) {
1151 return NULL;
1152 } else {
1153 // This load races with inserts, and therefore needs acquire.
1154 Klass* kls = Atomic::load_acquire(k);
1155 if (kls != NULL && !kls->is_loader_alive()) {
1156 return NULL; // don't return unloaded class
1157 } else {
1158 return kls;
1159 }
1160 }
1161 }
1162
1163
1164 void InstanceKlass::set_implementor(Klass* k) {
1165 assert_locked_or_safepoint(Compile_lock);
1166 assert(is_interface(), "not interface");
1167 Klass* volatile* addr = adr_implementor();
1168 assert(addr != NULL, "null addr");
1169 if (addr != NULL) {
1170 Atomic::release_store(addr, k);
1171 }
1172 }
1173
1174 int InstanceKlass::nof_implementors() const {
1175 Klass* k = implementor();
1176 if (k == NULL) {
1177 return 0;
1178 } else if (k != this) {
1179 return 1;
1180 } else {
1181 return 2;
1182 }
1183 }
1184
1185 // The embedded _implementor field can only record one implementor.
1186 // When there are more than one implementors, the _implementor field
1187 // is set to the interface Klass* itself. Following are the possible
1188 // values for the _implementor field:
1189 // NULL - no implementor
1190 // implementor Klass* - one implementor
1191 // self - more than one implementor
1192 //
1193 // The _implementor field only exists for interfaces.
1194 void InstanceKlass::add_implementor(Klass* k) {
1195 if (Universe::is_fully_initialized()) {
1196 assert_lock_strong(Compile_lock);
1197 }
1198 assert(is_interface(), "not interface");
1199 // Filter out my subinterfaces.
1200 // (Note: Interfaces are never on the subklass list.)
1201 if (InstanceKlass::cast(k)->is_interface()) return;
1202
1203 // Filter out subclasses whose supers already implement me.
1204 // (Note: CHA must walk subclasses of direct implementors
1205 // in order to locate indirect implementors.)
1206 Klass* sk = k->super();
1207 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1208 // We only need to check one immediate superclass, since the
1209 // implements_interface query looks at transitive_interfaces.
1210 // Any supers of the super have the same (or fewer) transitive_interfaces.
1211 return;
1212
1213 Klass* ik = implementor();
1214 if (ik == NULL) {
1215 set_implementor(k);
1216 } else if (ik != this && ik != k) {
1217 // There is already an implementor. Use itself as an indicator of
1218 // more than one implementors.
1219 set_implementor(this);
1220 }
1221
1222 // The implementor also implements the transitive_interfaces
1223 for (int index = 0; index < local_interfaces()->length(); index++) {
1224 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1225 }
1226 }
1227
1228 void InstanceKlass::init_implementor() {
1229 if (is_interface()) {
1230 set_implementor(NULL);
1231 }
1232 }
1233
1234
1235 void InstanceKlass::process_interfaces(Thread *thread) {
1236 // link this class into the implementors list of every interface it implements
1237 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1238 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1239 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1240 assert(interf->is_interface(), "expected interface");
1241 interf->add_implementor(this);
1242 }
1243 }
1244
1245 bool InstanceKlass::can_be_primary_super_slow() const {
1246 if (is_interface())
1247 return false;
1248 else
1249 return Klass::can_be_primary_super_slow();
1250 }
1251
1252 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1253 Array<InstanceKlass*>* transitive_interfaces) {
1254 // The secondaries are the implemented interfaces.
1255 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1256 int num_secondaries = num_extra_slots + interfaces->length();
1257 if (num_secondaries == 0) {
1258 // Must share this for correct bootstrapping!
1259 set_secondary_supers(Universe::the_empty_klass_array());
1260 return NULL;
1261 } else if (num_extra_slots == 0) {
1262 // The secondary super list is exactly the same as the transitive interfaces, so
1263 // let's use it instead of making a copy.
1264 // Redefine classes has to be careful not to delete this!
1265 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1266 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1267 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1268 return NULL;
1269 } else {
1270 // Copy transitive interfaces to a temporary growable array to be constructed
1271 // into the secondary super list with extra slots.
1272 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1273 for (int i = 0; i < interfaces->length(); i++) {
1274 secondaries->push(interfaces->at(i));
1275 }
1276 return secondaries;
1277 }
1278 }
1279
1280 bool InstanceKlass::implements_interface(Klass* k) const {
1281 if (this == k) return true;
1282 assert(k->is_interface(), "should be an interface class");
1283 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1284 if (transitive_interfaces()->at(i) == k) {
1285 return true;
1286 }
1287 }
1288 return false;
1289 }
1290
1291 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1292 // Verify direct super interface
1293 if (this == k) return true;
1294 assert(k->is_interface(), "should be an interface class");
1295 for (int i = 0; i < local_interfaces()->length(); i++) {
1296 if (local_interfaces()->at(i) == k) {
1297 return true;
1298 }
1299 }
1300 return false;
1301 }
1302
1303 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1304 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1305 int size = objArrayOopDesc::object_size(length);
1306 Klass* ak = array_klass(n, CHECK_NULL);
1307 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1308 /* do_zero */ true, CHECK_NULL);
1309 return o;
1310 }
1311
1312 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1313 if (TraceFinalizerRegistration) {
1314 tty->print("Registered ");
1315 i->print_value_on(tty);
1316 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1317 }
1318 instanceHandle h_i(THREAD, i);
1319 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1320 JavaValue result(T_VOID);
1321 JavaCallArguments args(h_i);
1322 methodHandle mh (THREAD, Universe::finalizer_register_method());
1323 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1324 return h_i();
1325 }
1326
1327 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1328 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1329 int size = size_helper(); // Query before forming handle.
1330
1331 instanceOop i;
1332
1333 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1334 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1335 i = register_finalizer(i, CHECK_NULL);
1336 }
1337 return i;
1338 }
1339
1340 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1341 return instanceHandle(THREAD, allocate_instance(THREAD));
1342 }
1343
1344 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1345 if (is_interface() || is_abstract()) {
1346 ResourceMark rm(THREAD);
1347 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1348 : vmSymbols::java_lang_InstantiationException(), external_name());
1349 }
1350 if (this == SystemDictionary::Class_klass()) {
1351 ResourceMark rm(THREAD);
1352 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1353 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1354 }
1355 }
1356
1357 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1358 // Need load-acquire for lock-free read
1359 if (array_klasses_acquire() == NULL) {
1360 if (or_null) return NULL;
1361
1362 ResourceMark rm(THREAD);
1363 JavaThread *jt = (JavaThread *)THREAD;
1364 {
1365 // Atomic creation of array_klasses
1366 MutexLocker ma(THREAD, MultiArray_lock);
1367
1368 // Check if update has already taken place
1369 if (array_klasses() == NULL) {
1370 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1371 // use 'release' to pair with lock-free load
1372 release_set_array_klasses(k);
1373 }
1374 }
1375 }
1376 // _this will always be set at this point
1377 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1378 if (or_null) {
1379 return oak->array_klass_or_null(n);
1380 }
1381 return oak->array_klass(n, THREAD);
1382 }
1383
1384 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1385 return array_klass_impl(or_null, 1, THREAD);
1386 }
1387
1388 static int call_class_initializer_counter = 0; // for debugging
1389
1390 Method* InstanceKlass::class_initializer() const {
1391 Method* clinit = find_method(
1392 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1393 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1394 return clinit;
1395 }
1396 return NULL;
1397 }
1398
1399 void InstanceKlass::call_class_initializer(TRAPS) {
1400 if (ReplayCompiles &&
1401 (ReplaySuppressInitializers == 1 ||
1402 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1403 // Hide the existence of the initializer for the purpose of replaying the compile
1404 return;
1405 }
1406
1407 methodHandle h_method(THREAD, class_initializer());
1408 assert(!is_initialized(), "we cannot initialize twice");
1409 LogTarget(Info, class, init) lt;
1410 if (lt.is_enabled()) {
1411 ResourceMark rm(THREAD);
1412 LogStream ls(lt);
1413 ls.print("%d Initializing ", call_class_initializer_counter++);
1414 name()->print_value_on(&ls);
1415 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1416 }
1417 if (h_method() != NULL) {
1418 JavaCallArguments args; // No arguments
1419 JavaValue result(T_VOID);
1420 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1421 }
1422 }
1423
1424
1425 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1426 InterpreterOopMap* entry_for) {
1427 // Lazily create the _oop_map_cache at first request
1428 // Lock-free access requires load_acquire.
1429 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1430 if (oop_map_cache == NULL) {
1431 MutexLocker x(OopMapCacheAlloc_lock);
1432 // Check if _oop_map_cache was allocated while we were waiting for this lock
1433 if ((oop_map_cache = _oop_map_cache) == NULL) {
1434 oop_map_cache = new OopMapCache();
1435 // Ensure _oop_map_cache is stable, since it is examined without a lock
1436 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1437 }
1438 }
1439 // _oop_map_cache is constant after init; lookup below does its own locking.
1440 oop_map_cache->lookup(method, bci, entry_for);
1441 }
1442
1443 bool InstanceKlass::contains_field_offset(int offset) {
1444 fieldDescriptor fd;
1445 return find_field_from_offset(offset, false, &fd);
1446 }
1447
1448 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1449 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1450 Symbol* f_name = fs.name();
1451 Symbol* f_sig = fs.signature();
1452 if (f_name == name && f_sig == sig) {
1453 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1454 return true;
1455 }
1456 }
1457 return false;
1458 }
1459
1460
1461 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1462 const int n = local_interfaces()->length();
1463 for (int i = 0; i < n; i++) {
1464 Klass* intf1 = local_interfaces()->at(i);
1465 assert(intf1->is_interface(), "just checking type");
1466 // search for field in current interface
1467 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1468 assert(fd->is_static(), "interface field must be static");
1469 return intf1;
1470 }
1471 // search for field in direct superinterfaces
1472 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1473 if (intf2 != NULL) return intf2;
1474 }
1475 // otherwise field lookup fails
1476 return NULL;
1477 }
1478
1479
1480 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1481 // search order according to newest JVM spec (5.4.3.2, p.167).
1482 // 1) search for field in current klass
1483 if (find_local_field(name, sig, fd)) {
1484 return const_cast<InstanceKlass*>(this);
1485 }
1486 // 2) search for field recursively in direct superinterfaces
1487 { Klass* intf = find_interface_field(name, sig, fd);
1488 if (intf != NULL) return intf;
1489 }
1490 // 3) apply field lookup recursively if superclass exists
1491 { Klass* supr = super();
1492 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1493 }
1494 // 4) otherwise field lookup fails
1495 return NULL;
1496 }
1497
1498
1499 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1500 // search order according to newest JVM spec (5.4.3.2, p.167).
1501 // 1) search for field in current klass
1502 if (find_local_field(name, sig, fd)) {
1503 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1504 }
1505 // 2) search for field recursively in direct superinterfaces
1506 if (is_static) {
1507 Klass* intf = find_interface_field(name, sig, fd);
1508 if (intf != NULL) return intf;
1509 }
1510 // 3) apply field lookup recursively if superclass exists
1511 { Klass* supr = super();
1512 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1513 }
1514 // 4) otherwise field lookup fails
1515 return NULL;
1516 }
1517
1518
1519 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1520 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1521 if (fs.offset() == offset) {
1522 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1523 if (fd->is_static() == is_static) return true;
1524 }
1525 }
1526 return false;
1527 }
1528
1529
1530 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1531 Klass* klass = const_cast<InstanceKlass*>(this);
1532 while (klass != NULL) {
1533 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1534 return true;
1535 }
1536 klass = klass->super();
1537 }
1538 return false;
1539 }
1540
1541
1542 void InstanceKlass::methods_do(void f(Method* method)) {
1543 // Methods aren't stable until they are loaded. This can be read outside
1544 // a lock through the ClassLoaderData for profiling
1545 if (!is_loaded()) {
1546 return;
1547 }
1548
1549 int len = methods()->length();
1550 for (int index = 0; index < len; index++) {
1551 Method* m = methods()->at(index);
1552 assert(m->is_method(), "must be method");
1553 f(m);
1554 }
1555 }
1556
1557
1558 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1559 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1560 if (fs.access_flags().is_static()) {
1561 fieldDescriptor& fd = fs.field_descriptor();
1562 cl->do_field(&fd);
1563 }
1564 }
1565 }
1566
1567
1568 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1569 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1570 if (fs.access_flags().is_static()) {
1571 fieldDescriptor& fd = fs.field_descriptor();
1572 f(&fd, mirror, CHECK);
1573 }
1574 }
1575 }
1576
1577
1578 static int compare_fields_by_offset(int* a, int* b) {
1579 return a[0] - b[0];
1580 }
1581
1582 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1583 InstanceKlass* super = superklass();
1584 if (super != NULL) {
1585 super->do_nonstatic_fields(cl);
1586 }
1587 fieldDescriptor fd;
1588 int length = java_fields_count();
1589 // In DebugInfo nonstatic fields are sorted by offset.
1590 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1591 int j = 0;
1592 for (int i = 0; i < length; i += 1) {
1593 fd.reinitialize(this, i);
1594 if (!fd.is_static()) {
1595 fields_sorted[j + 0] = fd.offset();
1596 fields_sorted[j + 1] = i;
1597 j += 2;
1598 }
1599 }
1600 if (j > 0) {
1601 length = j;
1602 // _sort_Fn is defined in growableArray.hpp.
1603 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1604 for (int i = 0; i < length; i += 2) {
1605 fd.reinitialize(this, fields_sorted[i + 1]);
1606 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1607 cl->do_field(&fd);
1608 }
1609 }
1610 FREE_C_HEAP_ARRAY(int, fields_sorted);
1611 }
1612
1613
1614 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1615 if (array_klasses() != NULL)
1616 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1617 }
1618
1619 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1620 if (array_klasses() != NULL)
1621 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1622 }
1623
1624 #ifdef ASSERT
1625 static int linear_search(const Array<Method*>* methods,
1626 const Symbol* name,
1627 const Symbol* signature) {
1628 const int len = methods->length();
1629 for (int index = 0; index < len; index++) {
1630 const Method* const m = methods->at(index);
1631 assert(m->is_method(), "must be method");
1632 if (m->signature() == signature && m->name() == name) {
1633 return index;
1634 }
1635 }
1636 return -1;
1637 }
1638 #endif
1639
1640 bool InstanceKlass::_disable_method_binary_search = false;
1641
1642 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1643 int len = methods->length();
1644 int l = 0;
1645 int h = len - 1;
1646 while (l <= h) {
1647 Method* m = methods->at(l);
1648 if (m->name() == name) {
1649 return l;
1650 }
1651 l++;
1652 }
1653 return -1;
1654 }
1655
1656 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1657 if (_disable_method_binary_search) {
1658 assert(DynamicDumpSharedSpaces, "must be");
1659 // At the final stage of dynamic dumping, the methods array may not be sorted
1660 // by ascending addresses of their names, so we can't use binary search anymore.
1661 // However, methods with the same name are still laid out consecutively inside the
1662 // methods array, so let's look for the first one that matches.
1663 return linear_search(methods, name);
1664 }
1665
1666 int len = methods->length();
1667 int l = 0;
1668 int h = len - 1;
1669
1670 // methods are sorted by ascending addresses of their names, so do binary search
1671 while (l <= h) {
1672 int mid = (l + h) >> 1;
1673 Method* m = methods->at(mid);
1674 assert(m->is_method(), "must be method");
1675 int res = m->name()->fast_compare(name);
1676 if (res == 0) {
1677 return mid;
1678 } else if (res < 0) {
1679 l = mid + 1;
1680 } else {
1681 h = mid - 1;
1682 }
1683 }
1684 return -1;
1685 }
1686
1687 // find_method looks up the name/signature in the local methods array
1688 Method* InstanceKlass::find_method(const Symbol* name,
1689 const Symbol* signature) const {
1690 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1691 }
1692
1693 Method* InstanceKlass::find_method_impl(const Symbol* name,
1694 const Symbol* signature,
1695 OverpassLookupMode overpass_mode,
1696 StaticLookupMode static_mode,
1697 PrivateLookupMode private_mode) const {
1698 return InstanceKlass::find_method_impl(methods(),
1699 name,
1700 signature,
1701 overpass_mode,
1702 static_mode,
1703 private_mode);
1704 }
1705
1706 // find_instance_method looks up the name/signature in the local methods array
1707 // and skips over static methods
1708 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1709 const Symbol* name,
1710 const Symbol* signature,
1711 PrivateLookupMode private_mode) {
1712 Method* const meth = InstanceKlass::find_method_impl(methods,
1713 name,
1714 signature,
1715 find_overpass,
1716 skip_static,
1717 private_mode);
1718 assert(((meth == NULL) || !meth->is_static()),
1719 "find_instance_method should have skipped statics");
1720 return meth;
1721 }
1722
1723 // find_instance_method looks up the name/signature in the local methods array
1724 // and skips over static methods
1725 Method* InstanceKlass::find_instance_method(const Symbol* name,
1726 const Symbol* signature,
1727 PrivateLookupMode private_mode) const {
1728 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1729 }
1730
1731 // Find looks up the name/signature in the local methods array
1732 // and filters on the overpass, static and private flags
1733 // This returns the first one found
1734 // note that the local methods array can have up to one overpass, one static
1735 // and one instance (private or not) with the same name/signature
1736 Method* InstanceKlass::find_local_method(const Symbol* name,
1737 const Symbol* signature,
1738 OverpassLookupMode overpass_mode,
1739 StaticLookupMode static_mode,
1740 PrivateLookupMode private_mode) const {
1741 return InstanceKlass::find_method_impl(methods(),
1742 name,
1743 signature,
1744 overpass_mode,
1745 static_mode,
1746 private_mode);
1747 }
1748
1749 // Find looks up the name/signature in the local methods array
1750 // and filters on the overpass, static and private flags
1751 // This returns the first one found
1752 // note that the local methods array can have up to one overpass, one static
1753 // and one instance (private or not) with the same name/signature
1754 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1755 const Symbol* name,
1756 const Symbol* signature,
1757 OverpassLookupMode overpass_mode,
1758 StaticLookupMode static_mode,
1759 PrivateLookupMode private_mode) {
1760 return InstanceKlass::find_method_impl(methods,
1761 name,
1762 signature,
1763 overpass_mode,
1764 static_mode,
1765 private_mode);
1766 }
1767
1768 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1769 const Symbol* name,
1770 const Symbol* signature) {
1771 return InstanceKlass::find_method_impl(methods,
1772 name,
1773 signature,
1774 find_overpass,
1775 find_static,
1776 find_private);
1777 }
1778
1779 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1780 const Symbol* name,
1781 const Symbol* signature,
1782 OverpassLookupMode overpass_mode,
1783 StaticLookupMode static_mode,
1784 PrivateLookupMode private_mode) {
1785 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1786 return hit >= 0 ? methods->at(hit): NULL;
1787 }
1788
1789 // true if method matches signature and conforms to skipping_X conditions.
1790 static bool method_matches(const Method* m,
1791 const Symbol* signature,
1792 bool skipping_overpass,
1793 bool skipping_static,
1794 bool skipping_private) {
1795 return ((m->signature() == signature) &&
1796 (!skipping_overpass || !m->is_overpass()) &&
1797 (!skipping_static || !m->is_static()) &&
1798 (!skipping_private || !m->is_private()));
1799 }
1800
1801 // Used directly for default_methods to find the index into the
1802 // default_vtable_indices, and indirectly by find_method
1803 // find_method_index looks in the local methods array to return the index
1804 // of the matching name/signature. If, overpass methods are being ignored,
1805 // the search continues to find a potential non-overpass match. This capability
1806 // is important during method resolution to prefer a static method, for example,
1807 // over an overpass method.
1808 // There is the possibility in any _method's array to have the same name/signature
1809 // for a static method, an overpass method and a local instance method
1810 // To correctly catch a given method, the search criteria may need
1811 // to explicitly skip the other two. For local instance methods, it
1812 // is often necessary to skip private methods
1813 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1814 const Symbol* name,
1815 const Symbol* signature,
1816 OverpassLookupMode overpass_mode,
1817 StaticLookupMode static_mode,
1818 PrivateLookupMode private_mode) {
1819 const bool skipping_overpass = (overpass_mode == skip_overpass);
1820 const bool skipping_static = (static_mode == skip_static);
1821 const bool skipping_private = (private_mode == skip_private);
1822 const int hit = quick_search(methods, name);
1823 if (hit != -1) {
1824 const Method* const m = methods->at(hit);
1825
1826 // Do linear search to find matching signature. First, quick check
1827 // for common case, ignoring overpasses if requested.
1828 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1829 return hit;
1830 }
1831
1832 // search downwards through overloaded methods
1833 int i;
1834 for (i = hit - 1; i >= 0; --i) {
1835 const Method* const m = methods->at(i);
1836 assert(m->is_method(), "must be method");
1837 if (m->name() != name) {
1838 break;
1839 }
1840 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1841 return i;
1842 }
1843 }
1844 // search upwards
1845 for (i = hit + 1; i < methods->length(); ++i) {
1846 const Method* const m = methods->at(i);
1847 assert(m->is_method(), "must be method");
1848 if (m->name() != name) {
1849 break;
1850 }
1851 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1852 return i;
1853 }
1854 }
1855 // not found
1856 #ifdef ASSERT
1857 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1858 linear_search(methods, name, signature);
1859 assert(-1 == index, "binary search should have found entry %d", index);
1860 #endif
1861 }
1862 return -1;
1863 }
1864
1865 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1866 return find_method_by_name(methods(), name, end);
1867 }
1868
1869 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1870 const Symbol* name,
1871 int* end_ptr) {
1872 assert(end_ptr != NULL, "just checking");
1873 int start = quick_search(methods, name);
1874 int end = start + 1;
1875 if (start != -1) {
1876 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1877 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1878 *end_ptr = end;
1879 return start;
1880 }
1881 return -1;
1882 }
1883
1884 // uncached_lookup_method searches both the local class methods array and all
1885 // superclasses methods arrays, skipping any overpass methods in superclasses,
1886 // and possibly skipping private methods.
1887 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1888 const Symbol* signature,
1889 OverpassLookupMode overpass_mode,
1890 PrivateLookupMode private_mode) const {
1891 OverpassLookupMode overpass_local_mode = overpass_mode;
1892 const Klass* klass = this;
1893 while (klass != NULL) {
1894 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1895 signature,
1896 overpass_local_mode,
1897 find_static,
1898 private_mode);
1899 if (method != NULL) {
1900 return method;
1901 }
1902 klass = klass->super();
1903 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1904 }
1905 return NULL;
1906 }
1907
1908 #ifdef ASSERT
1909 // search through class hierarchy and return true if this class or
1910 // one of the superclasses was redefined
1911 bool InstanceKlass::has_redefined_this_or_super() const {
1912 const Klass* klass = this;
1913 while (klass != NULL) {
1914 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1915 return true;
1916 }
1917 klass = klass->super();
1918 }
1919 return false;
1920 }
1921 #endif
1922
1923 // lookup a method in the default methods list then in all transitive interfaces
1924 // Do NOT return private or static methods
1925 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1926 Symbol* signature) const {
1927 Method* m = NULL;
1928 if (default_methods() != NULL) {
1929 m = find_method(default_methods(), name, signature);
1930 }
1931 // Look up interfaces
1932 if (m == NULL) {
1933 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1934 }
1935 return m;
1936 }
1937
1938 // lookup a method in all the interfaces that this class implements
1939 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1940 // They should only be found in the initial InterfaceMethodRef
1941 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1942 Symbol* signature,
1943 DefaultsLookupMode defaults_mode) const {
1944 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1945 int num_ifs = all_ifs->length();
1946 InstanceKlass *ik = NULL;
1947 for (int i = 0; i < num_ifs; i++) {
1948 ik = all_ifs->at(i);
1949 Method* m = ik->lookup_method(name, signature);
1950 if (m != NULL && m->is_public() && !m->is_static() &&
1951 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1952 return m;
1953 }
1954 }
1955 return NULL;
1956 }
1957
1958 /* jni_id_for_impl for jfieldIds only */
1959 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1960 MutexLocker ml(JfieldIdCreation_lock);
1961 // Retry lookup after we got the lock
1962 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1963 if (probe == NULL) {
1964 // Slow case, allocate new static field identifier
1965 probe = new JNIid(this, offset, jni_ids());
1966 set_jni_ids(probe);
1967 }
1968 return probe;
1969 }
1970
1971
1972 /* jni_id_for for jfieldIds only */
1973 JNIid* InstanceKlass::jni_id_for(int offset) {
1974 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1975 if (probe == NULL) {
1976 probe = jni_id_for_impl(offset);
1977 }
1978 return probe;
1979 }
1980
1981 u2 InstanceKlass::enclosing_method_data(int offset) const {
1982 const Array<jushort>* const inner_class_list = inner_classes();
1983 if (inner_class_list == NULL) {
1984 return 0;
1985 }
1986 const int length = inner_class_list->length();
1987 if (length % inner_class_next_offset == 0) {
1988 return 0;
1989 }
1990 const int index = length - enclosing_method_attribute_size;
1991 assert(offset < enclosing_method_attribute_size, "invalid offset");
1992 return inner_class_list->at(index + offset);
1993 }
1994
1995 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1996 u2 method_index) {
1997 Array<jushort>* inner_class_list = inner_classes();
1998 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1999 int length = inner_class_list->length();
2000 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2001 int index = length - enclosing_method_attribute_size;
2002 inner_class_list->at_put(
2003 index + enclosing_method_class_index_offset, class_index);
2004 inner_class_list->at_put(
2005 index + enclosing_method_method_index_offset, method_index);
2006 }
2007 }
2008
2009 // Lookup or create a jmethodID.
2010 // This code is called by the VMThread and JavaThreads so the
2011 // locking has to be done very carefully to avoid deadlocks
2012 // and/or other cache consistency problems.
2013 //
2014 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2015 size_t idnum = (size_t)method_h->method_idnum();
2016 jmethodID* jmeths = methods_jmethod_ids_acquire();
2017 size_t length = 0;
2018 jmethodID id = NULL;
2019
2020 // We use a double-check locking idiom here because this cache is
2021 // performance sensitive. In the normal system, this cache only
2022 // transitions from NULL to non-NULL which is safe because we use
2023 // release_set_methods_jmethod_ids() to advertise the new cache.
2024 // A partially constructed cache should never be seen by a racing
2025 // thread. We also use release_store() to save a new jmethodID
2026 // in the cache so a partially constructed jmethodID should never be
2027 // seen either. Cache reads of existing jmethodIDs proceed without a
2028 // lock, but cache writes of a new jmethodID requires uniqueness and
2029 // creation of the cache itself requires no leaks so a lock is
2030 // generally acquired in those two cases.
2031 //
2032 // If the RedefineClasses() API has been used, then this cache can
2033 // grow and we'll have transitions from non-NULL to bigger non-NULL.
2034 // Cache creation requires no leaks and we require safety between all
2035 // cache accesses and freeing of the old cache so a lock is generally
2036 // acquired when the RedefineClasses() API has been used.
2037
2038 if (jmeths != NULL) {
2039 // the cache already exists
2040 if (!idnum_can_increment()) {
2041 // the cache can't grow so we can just get the current values
2042 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2043 } else {
2044 // cache can grow so we have to be more careful
2045 if (Threads::number_of_threads() == 0 ||
2046 SafepointSynchronize::is_at_safepoint()) {
2047 // we're single threaded or at a safepoint - no locking needed
2048 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2049 } else {
2050 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2051 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2052 }
2053 }
2054 }
2055 // implied else:
2056 // we need to allocate a cache so default length and id values are good
2057
2058 if (jmeths == NULL || // no cache yet
2059 length <= idnum || // cache is too short
2060 id == NULL) { // cache doesn't contain entry
2061
2062 // This function can be called by the VMThread so we have to do all
2063 // things that might block on a safepoint before grabbing the lock.
2064 // Otherwise, we can deadlock with the VMThread or have a cache
2065 // consistency issue. These vars keep track of what we might have
2066 // to free after the lock is dropped.
2067 jmethodID to_dealloc_id = NULL;
2068 jmethodID* to_dealloc_jmeths = NULL;
2069
2070 // may not allocate new_jmeths or use it if we allocate it
2071 jmethodID* new_jmeths = NULL;
2072 if (length <= idnum) {
2073 // allocate a new cache that might be used
2074 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2075 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2076 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2077 // cache size is stored in element[0], other elements offset by one
2078 new_jmeths[0] = (jmethodID)size;
2079 }
2080
2081 // allocate a new jmethodID that might be used
2082 jmethodID new_id = NULL;
2083 if (method_h->is_old() && !method_h->is_obsolete()) {
2084 // The method passed in is old (but not obsolete), we need to use the current version
2085 Method* current_method = method_with_idnum((int)idnum);
2086 assert(current_method != NULL, "old and but not obsolete, so should exist");
2087 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2088 } else {
2089 // It is the current version of the method or an obsolete method,
2090 // use the version passed in
2091 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2092 }
2093
2094 if (Threads::number_of_threads() == 0 ||
2095 SafepointSynchronize::is_at_safepoint()) {
2096 // we're single threaded or at a safepoint - no locking needed
2097 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2098 &to_dealloc_id, &to_dealloc_jmeths);
2099 } else {
2100 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2101 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2102 &to_dealloc_id, &to_dealloc_jmeths);
2103 }
2104
2105 // The lock has been dropped so we can free resources.
2106 // Free up either the old cache or the new cache if we allocated one.
2107 if (to_dealloc_jmeths != NULL) {
2108 FreeHeap(to_dealloc_jmeths);
2109 }
2110 // free up the new ID since it wasn't needed
2111 if (to_dealloc_id != NULL) {
2112 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2113 }
2114 }
2115 return id;
2116 }
2117
2118 // Figure out how many jmethodIDs haven't been allocated, and make
2119 // sure space for them is pre-allocated. This makes getting all
2120 // method ids much, much faster with classes with more than 8
2121 // methods, and has a *substantial* effect on performance with jvmti
2122 // code that loads all jmethodIDs for all classes.
2123 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2124 int new_jmeths = 0;
2125 int length = methods()->length();
2126 for (int index = start_offset; index < length; index++) {
2127 Method* m = methods()->at(index);
2128 jmethodID id = m->find_jmethod_id_or_null();
2129 if (id == NULL) {
2130 new_jmeths++;
2131 }
2132 }
2133 if (new_jmeths != 0) {
2134 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2135 }
2136 }
2137
2138 // Common code to fetch the jmethodID from the cache or update the
2139 // cache with the new jmethodID. This function should never do anything
2140 // that causes the caller to go to a safepoint or we can deadlock with
2141 // the VMThread or have cache consistency issues.
2142 //
2143 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2144 size_t idnum, jmethodID new_id,
2145 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2146 jmethodID** to_dealloc_jmeths_p) {
2147 assert(new_id != NULL, "sanity check");
2148 assert(to_dealloc_id_p != NULL, "sanity check");
2149 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2150 assert(Threads::number_of_threads() == 0 ||
2151 SafepointSynchronize::is_at_safepoint() ||
2152 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2153
2154 // reacquire the cache - we are locked, single threaded or at a safepoint
2155 jmethodID* jmeths = methods_jmethod_ids_acquire();
2156 jmethodID id = NULL;
2157 size_t length = 0;
2158
2159 if (jmeths == NULL || // no cache yet
2160 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2161 if (jmeths != NULL) {
2162 // copy any existing entries from the old cache
2163 for (size_t index = 0; index < length; index++) {
2164 new_jmeths[index+1] = jmeths[index+1];
2165 }
2166 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2167 }
2168 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2169 } else {
2170 // fetch jmethodID (if any) from the existing cache
2171 id = jmeths[idnum+1];
2172 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2173 }
2174 if (id == NULL) {
2175 // No matching jmethodID in the existing cache or we have a new
2176 // cache or we just grew the cache. This cache write is done here
2177 // by the first thread to win the foot race because a jmethodID
2178 // needs to be unique once it is generally available.
2179 id = new_id;
2180
2181 // The jmethodID cache can be read while unlocked so we have to
2182 // make sure the new jmethodID is complete before installing it
2183 // in the cache.
2184 Atomic::release_store(&jmeths[idnum+1], id);
2185 } else {
2186 *to_dealloc_id_p = new_id; // save new id for later delete
2187 }
2188 return id;
2189 }
2190
2191
2192 // Common code to get the jmethodID cache length and the jmethodID
2193 // value at index idnum if there is one.
2194 //
2195 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2196 size_t idnum, size_t *length_p, jmethodID* id_p) {
2197 assert(cache != NULL, "sanity check");
2198 assert(length_p != NULL, "sanity check");
2199 assert(id_p != NULL, "sanity check");
2200
2201 // cache size is stored in element[0], other elements offset by one
2202 *length_p = (size_t)cache[0];
2203 if (*length_p <= idnum) { // cache is too short
2204 *id_p = NULL;
2205 } else {
2206 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2207 }
2208 }
2209
2210
2211 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2212 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2213 size_t idnum = (size_t)method->method_idnum();
2214 jmethodID* jmeths = methods_jmethod_ids_acquire();
2215 size_t length; // length assigned as debugging crumb
2216 jmethodID id = NULL;
2217 if (jmeths != NULL && // If there is a cache
2218 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2219 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2220 }
2221 return id;
2222 }
2223
2224 inline DependencyContext InstanceKlass::dependencies() {
2225 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2226 return dep_context;
2227 }
2228
2229 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2230 return dependencies().mark_dependent_nmethods(changes);
2231 }
2232
2233 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2234 dependencies().add_dependent_nmethod(nm);
2235 }
2236
2237 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2238 dependencies().remove_dependent_nmethod(nm);
2239 }
2240
2241 void InstanceKlass::clean_dependency_context() {
2242 dependencies().clean_unloading_dependents();
2243 }
2244
2245 #ifndef PRODUCT
2246 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2247 dependencies().print_dependent_nmethods(verbose);
2248 }
2249
2250 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2251 return dependencies().is_dependent_nmethod(nm);
2252 }
2253 #endif //PRODUCT
2254
2255 void InstanceKlass::clean_weak_instanceklass_links() {
2256 clean_implementors_list();
2257 clean_method_data();
2258 }
2259
2260 void InstanceKlass::clean_implementors_list() {
2261 assert(is_loader_alive(), "this klass should be live");
2262 if (is_interface()) {
2263 assert (ClassUnloading, "only called for ClassUnloading");
2264 for (;;) {
2265 // Use load_acquire due to competing with inserts
2266 Klass* impl = Atomic::load_acquire(adr_implementor());
2267 if (impl != NULL && !impl->is_loader_alive()) {
2268 // NULL this field, might be an unloaded klass or NULL
2269 Klass* volatile* klass = adr_implementor();
2270 if (Atomic::cmpxchg(klass, impl, (Klass*)NULL) == impl) {
2271 // Successfully unlinking implementor.
2272 if (log_is_enabled(Trace, class, unload)) {
2273 ResourceMark rm;
2274 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2275 }
2276 return;
2277 }
2278 } else {
2279 return;
2280 }
2281 }
2282 }
2283 }
2284
2285 void InstanceKlass::clean_method_data() {
2286 for (int m = 0; m < methods()->length(); m++) {
2287 MethodData* mdo = methods()->at(m)->method_data();
2288 if (mdo != NULL) {
2289 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock());
2290 mdo->clean_method_data(/*always_clean*/false);
2291 }
2292 }
2293 }
2294
2295 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2296 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2297 ResourceMark rm;
2298 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2299 return false;
2300 }
2301
2302 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2303 if (local_interfaces != NULL) {
2304 int length = local_interfaces->length();
2305 for (int i = 0; i < length; i++) {
2306 InstanceKlass* intf = local_interfaces->at(i);
2307 if (!intf->has_passed_fingerprint_check()) {
2308 ResourceMark rm;
2309 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2310 return false;
2311 }
2312 }
2313 }
2314
2315 return true;
2316 }
2317
2318 bool InstanceKlass::should_store_fingerprint(bool is_hidden_or_anonymous) {
2319 #if INCLUDE_AOT
2320 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2321 if (CalculateClassFingerprint) {
2322 // (1) We are running AOT to generate a shared library.
2323 return true;
2324 }
2325 if (Arguments::is_dumping_archive()) {
2326 // (2) We are running -Xshare:dump or -XX:ArchiveClassesAtExit to create a shared archive
2327 return true;
2328 }
2329 if (UseAOT && is_hidden_or_anonymous) {
2330 // (3) We are using AOT code from a shared library and see a hidden or unsafe anonymous class
2331 return true;
2332 }
2333 #endif
2334
2335 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2336 // but do not store the 64-bit fingerprint to save space.
2337 return false;
2338 }
2339
2340 bool InstanceKlass::has_stored_fingerprint() const {
2341 #if INCLUDE_AOT
2342 return should_store_fingerprint() || is_shared();
2343 #else
2344 return false;
2345 #endif
2346 }
2347
2348 uint64_t InstanceKlass::get_stored_fingerprint() const {
2349 address adr = adr_fingerprint();
2350 if (adr != NULL) {
2351 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2352 }
2353 return 0;
2354 }
2355
2356 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2357 address adr = adr_fingerprint();
2358 if (adr != NULL) {
2359 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2360
2361 ResourceMark rm;
2362 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2363 }
2364 }
2365
2366 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2367 Klass::metaspace_pointers_do(it);
2368
2369 if (log_is_enabled(Trace, cds)) {
2370 ResourceMark rm;
2371 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2372 }
2373
2374 it->push(&_annotations);
2375 it->push((Klass**)&_array_klasses);
2376 it->push(&_constants);
2377 it->push(&_inner_classes);
2378 it->push(&_array_name);
2379 #if INCLUDE_JVMTI
2380 it->push(&_previous_versions);
2381 #endif
2382 it->push(&_methods);
2383 it->push(&_default_methods);
2384 it->push(&_local_interfaces);
2385 it->push(&_transitive_interfaces);
2386 it->push(&_method_ordering);
2387 it->push(&_default_vtable_indices);
2388 it->push(&_fields);
2389
2390 if (itable_length() > 0) {
2391 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2392 int method_table_offset_in_words = ioe->offset()/wordSize;
2393 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2394 / itableOffsetEntry::size();
2395
2396 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2397 if (ioe->interface_klass() != NULL) {
2398 it->push(ioe->interface_klass_addr());
2399 itableMethodEntry* ime = ioe->first_method_entry(this);
2400 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2401 for (int index = 0; index < n; index ++) {
2402 it->push(ime[index].method_addr());
2403 }
2404 }
2405 }
2406 }
2407
2408 it->push(&_nest_members);
2409 it->push(&_record_components);
2410 }
2411
2412 void InstanceKlass::remove_unshareable_info() {
2413 Klass::remove_unshareable_info();
2414
2415 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2416 // Classes are attempted to link during dumping and may fail,
2417 // but these classes are still in the dictionary and class list in CLD.
2418 // If the class has failed verification, there is nothing else to remove.
2419 return;
2420 }
2421
2422 // Reset to the 'allocated' state to prevent any premature accessing to
2423 // a shared class at runtime while the class is still being loaded and
2424 // restored. A class' init_state is set to 'loaded' at runtime when it's
2425 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2426 _init_state = allocated;
2427
2428 { // Otherwise this needs to take out the Compile_lock.
2429 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2430 init_implementor();
2431 }
2432
2433 constants()->remove_unshareable_info();
2434
2435 for (int i = 0; i < methods()->length(); i++) {
2436 Method* m = methods()->at(i);
2437 m->remove_unshareable_info();
2438 }
2439
2440 // do array classes also.
2441 if (array_klasses() != NULL) {
2442 array_klasses()->remove_unshareable_info();
2443 }
2444
2445 // These are not allocated from metaspace. They are safe to set to NULL.
2446 _source_debug_extension = NULL;
2447 _dep_context = NULL;
2448 _osr_nmethods_head = NULL;
2449 #if INCLUDE_JVMTI
2450 _breakpoints = NULL;
2451 _previous_versions = NULL;
2452 _cached_class_file = NULL;
2453 _jvmti_cached_class_field_map = NULL;
2454 #endif
2455
2456 _init_thread = NULL;
2457 _methods_jmethod_ids = NULL;
2458 _jni_ids = NULL;
2459 _oop_map_cache = NULL;
2460 // clear _nest_host to ensure re-load at runtime
2461 _nest_host = NULL;
2462 _nest_host_res_error = NULL;
2463 _package_entry = NULL;
2464 _dep_context_last_cleaned = 0;
2465 }
2466
2467 void InstanceKlass::remove_java_mirror() {
2468 Klass::remove_java_mirror();
2469
2470 // do array classes also.
2471 if (array_klasses() != NULL) {
2472 array_klasses()->remove_java_mirror();
2473 }
2474 }
2475
2476 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2477 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2478 // before the InstanceKlass is added to the SystemDictionary. Make
2479 // sure the current state is <loaded.
2480 assert(!is_loaded(), "invalid init state");
2481 set_package(loader_data, CHECK);
2482 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2483
2484 Array<Method*>* methods = this->methods();
2485 int num_methods = methods->length();
2486 for (int index = 0; index < num_methods; ++index) {
2487 methods->at(index)->restore_unshareable_info(CHECK);
2488 }
2489 if (JvmtiExport::has_redefined_a_class()) {
2490 // Reinitialize vtable because RedefineClasses may have changed some
2491 // entries in this vtable for super classes so the CDS vtable might
2492 // point to old or obsolete entries. RedefineClasses doesn't fix up
2493 // vtables in the shared system dictionary, only the main one.
2494 // It also redefines the itable too so fix that too.
2495 vtable().initialize_vtable(false, CHECK);
2496 itable().initialize_itable(false, CHECK);
2497 }
2498
2499 // restore constant pool resolved references
2500 constants()->restore_unshareable_info(CHECK);
2501
2502 if (array_klasses() != NULL) {
2503 // Array classes have null protection domain.
2504 // --> see ArrayKlass::complete_create_array_klass()
2505 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2506 }
2507
2508 // Initialize current biased locking state.
2509 if (UseBiasedLocking && BiasedLocking::enabled()) {
2510 set_prototype_header(markWord::biased_locking_prototype());
2511 }
2512 }
2513
2514 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) {
2515 switch (loader_type) {
2516 case ClassLoader::BOOT_LOADER:
2517 _misc_flags |= _misc_is_shared_boot_class;
2518 break;
2519 case ClassLoader::PLATFORM_LOADER:
2520 _misc_flags |= _misc_is_shared_platform_class;
2521 break;
2522 case ClassLoader::APP_LOADER:
2523 _misc_flags |= _misc_is_shared_app_class;
2524 break;
2525 default:
2526 ShouldNotReachHere();
2527 break;
2528 }
2529 }
2530
2531 #if INCLUDE_JVMTI
2532 static void clear_all_breakpoints(Method* m) {
2533 m->clear_all_breakpoints();
2534 }
2535 #endif
2536
2537 void InstanceKlass::unload_class(InstanceKlass* ik) {
2538 // Release dependencies.
2539 ik->dependencies().remove_all_dependents();
2540
2541 // notify the debugger
2542 if (JvmtiExport::should_post_class_unload()) {
2543 JvmtiExport::post_class_unload(ik);
2544 }
2545
2546 // notify ClassLoadingService of class unload
2547 ClassLoadingService::notify_class_unloaded(ik);
2548
2549 if (Arguments::is_dumping_archive()) {
2550 SystemDictionaryShared::remove_dumptime_info(ik);
2551 }
2552
2553 if (log_is_enabled(Info, class, unload)) {
2554 ResourceMark rm;
2555 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik));
2556 }
2557
2558 Events::log_class_unloading(Thread::current(), ik);
2559
2560 #if INCLUDE_JFR
2561 assert(ik != NULL, "invariant");
2562 EventClassUnload event;
2563 event.set_unloadedClass(ik);
2564 event.set_definingClassLoader(ik->class_loader_data());
2565 event.commit();
2566 #endif
2567 }
2568
2569 static void method_release_C_heap_structures(Method* m) {
2570 m->release_C_heap_structures();
2571 }
2572
2573 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2574 // Clean up C heap
2575 ik->release_C_heap_structures();
2576 ik->constants()->release_C_heap_structures();
2577
2578 // Deallocate and call destructors for MDO mutexes
2579 ik->methods_do(method_release_C_heap_structures);
2580
2581 }
2582
2583 void InstanceKlass::release_C_heap_structures() {
2584 // Can't release the constant pool here because the constant pool can be
2585 // deallocated separately from the InstanceKlass for default methods and
2586 // redefine classes.
2587
2588 // Deallocate oop map cache
2589 if (_oop_map_cache != NULL) {
2590 delete _oop_map_cache;
2591 _oop_map_cache = NULL;
2592 }
2593
2594 // Deallocate JNI identifiers for jfieldIDs
2595 JNIid::deallocate(jni_ids());
2596 set_jni_ids(NULL);
2597
2598 jmethodID* jmeths = methods_jmethod_ids_acquire();
2599 if (jmeths != (jmethodID*)NULL) {
2600 release_set_methods_jmethod_ids(NULL);
2601 FreeHeap(jmeths);
2602 }
2603
2604 assert(_dep_context == NULL,
2605 "dependencies should already be cleaned");
2606
2607 #if INCLUDE_JVMTI
2608 // Deallocate breakpoint records
2609 if (breakpoints() != 0x0) {
2610 methods_do(clear_all_breakpoints);
2611 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2612 }
2613
2614 // deallocate the cached class file
2615 if (_cached_class_file != NULL) {
2616 os::free(_cached_class_file);
2617 _cached_class_file = NULL;
2618 }
2619 #endif
2620
2621 // Decrement symbol reference counts associated with the unloaded class.
2622 if (_name != NULL) _name->decrement_refcount();
2623
2624 // unreference array name derived from this class name (arrays of an unloaded
2625 // class can't be referenced anymore).
2626 if (_array_name != NULL) _array_name->decrement_refcount();
2627 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2628
2629 // deallocate memoized nest-host resolution error
2630 if (_nest_host_res_error != NULL) {
2631 FREE_C_HEAP_ARRAY(char, _nest_host_res_error);
2632 _nest_host_res_error = NULL;
2633 }
2634 }
2635
2636 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2637 if (array == NULL) {
2638 _source_debug_extension = NULL;
2639 } else {
2640 // Adding one to the attribute length in order to store a null terminator
2641 // character could cause an overflow because the attribute length is
2642 // already coded with an u4 in the classfile, but in practice, it's
2643 // unlikely to happen.
2644 assert((length+1) > length, "Overflow checking");
2645 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2646 for (int i = 0; i < length; i++) {
2647 sde[i] = array[i];
2648 }
2649 sde[length] = '\0';
2650 _source_debug_extension = sde;
2651 }
2652 }
2653
2654 const char* InstanceKlass::signature_name() const {
2655 int hash_len = 0;
2656 char hash_buf[40];
2657
2658 // If this is an unsafe anonymous class, append a hash to make the name unique
2659 if (is_unsafe_anonymous()) {
2660 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2661 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2662 hash_len = (int)strlen(hash_buf);
2663 }
2664
2665 // Get the internal name as a c string
2666 const char* src = (const char*) (name()->as_C_string());
2667 const int src_length = (int)strlen(src);
2668
2669 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2670
2671 // Add L as type indicator
2672 int dest_index = 0;
2673 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2674
2675 // Add the actual class name
2676 for (int src_index = 0; src_index < src_length; ) {
2677 dest[dest_index++] = src[src_index++];
2678 }
2679
2680 if (is_hidden()) { // Replace the last '+' with a '.'.
2681 for (int index = (int)src_length; index > 0; index--) {
2682 if (dest[index] == '+') {
2683 dest[index] = JVM_SIGNATURE_DOT;
2684 break;
2685 }
2686 }
2687 }
2688
2689 // If we have a hash, append it
2690 for (int hash_index = 0; hash_index < hash_len; ) {
2691 dest[dest_index++] = hash_buf[hash_index++];
2692 }
2693
2694 // Add the semicolon and the NULL
2695 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
2696 dest[dest_index] = '\0';
2697 return dest;
2698 }
2699
2700 // Used to obtain the package name from a fully qualified class name.
2701 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2702 if (name == NULL) {
2703 return NULL;
2704 } else {
2705 if (name->utf8_length() <= 0) {
2706 return NULL;
2707 }
2708 ResourceMark rm(THREAD);
2709 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2710 if (package_name == NULL) {
2711 return NULL;
2712 }
2713 Symbol* pkg_name = SymbolTable::new_symbol(package_name);
2714 return pkg_name;
2715 }
2716 }
2717
2718 ModuleEntry* InstanceKlass::module() const {
2719 // For an unsafe anonymous class return the host class' module
2720 if (is_unsafe_anonymous()) {
2721 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2722 return unsafe_anonymous_host()->module();
2723 }
2724
2725 if (is_hidden() &&
2726 in_unnamed_package() &&
2727 class_loader_data()->is_shortlived()) {
2728 // For a weak hidden class defined to an unnamed package,
2729 // the short-lived CLD will not have an unnamed module created for it.
2730 // Two choices to find the correct ModuleEntry:
2731 // 1. If hidden class is within a nest, use nest host's module
2732 // 2. Find the unnamed module off from the class loader
2733 // For now option #2 is used since a nest host is not set until
2734 // after the instance class is created in jvm_lookup_define_class().
2735 if (class_loader_data()->is_boot_class_loader_data()) {
2736 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
2737 } else {
2738 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
2739 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
2740 return java_lang_Module::module_entry(module);
2741 }
2742 }
2743
2744 // Class is in a named package
2745 if (!in_unnamed_package()) {
2746 return _package_entry->module();
2747 }
2748
2749 // Class is in an unnamed package, return its loader's unnamed module
2750 return class_loader_data()->unnamed_module();
2751 }
2752
2753 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2754
2755 // ensure java/ packages only loaded by boot or platform builtin loaders
2756 check_prohibited_package(name(), loader_data, CHECK);
2757
2758 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2759
2760 if (pkg_name != NULL && loader_data != NULL) {
2761
2762 // Find in class loader's package entry table.
2763 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2764
2765 // If the package name is not found in the loader's package
2766 // entry table, it is an indication that the package has not
2767 // been defined. Consider it defined within the unnamed module.
2768 if (_package_entry == NULL) {
2769 ResourceMark rm(THREAD);
2770
2771 if (!ModuleEntryTable::javabase_defined()) {
2772 // Before java.base is defined during bootstrapping, define all packages in
2773 // the java.base module. If a non-java.base package is erroneously placed
2774 // in the java.base module it will be caught later when java.base
2775 // is defined by ModuleEntryTable::verify_javabase_packages check.
2776 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2777 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2778 } else {
2779 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2780 _package_entry = loader_data->packages()->lookup(pkg_name,
2781 loader_data->unnamed_module());
2782 }
2783
2784 // A package should have been successfully created
2785 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2786 name()->as_C_string(), loader_data->loader_name_and_id());
2787 }
2788
2789 if (log_is_enabled(Debug, module)) {
2790 ResourceMark rm(THREAD);
2791 ModuleEntry* m = _package_entry->module();
2792 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2793 external_name(),
2794 pkg_name->as_C_string(),
2795 loader_data->loader_name_and_id(),
2796 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2797 }
2798 } else {
2799 ResourceMark rm(THREAD);
2800 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2801 external_name(),
2802 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2803 UNNAMED_MODULE);
2804 }
2805 }
2806
2807
2808 // different versions of is_same_class_package
2809
2810 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2811 oop classloader1 = this->class_loader();
2812 PackageEntry* classpkg1 = this->package();
2813 if (class2->is_objArray_klass()) {
2814 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2815 }
2816
2817 oop classloader2;
2818 PackageEntry* classpkg2;
2819 if (class2->is_instance_klass()) {
2820 classloader2 = class2->class_loader();
2821 classpkg2 = class2->package();
2822 } else {
2823 assert(class2->is_typeArray_klass(), "should be type array");
2824 classloader2 = NULL;
2825 classpkg2 = NULL;
2826 }
2827
2828 // Same package is determined by comparing class loader
2829 // and package entries. Both must be the same. This rule
2830 // applies even to classes that are defined in the unnamed
2831 // package, they still must have the same class loader.
2832 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2833 return true;
2834 }
2835
2836 return false;
2837 }
2838
2839 // return true if this class and other_class are in the same package. Classloader
2840 // and classname information is enough to determine a class's package
2841 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2842 const Symbol* other_class_name) const {
2843 if (class_loader() != other_class_loader) {
2844 return false;
2845 }
2846 if (name()->fast_compare(other_class_name) == 0) {
2847 return true;
2848 }
2849
2850 {
2851 ResourceMark rm;
2852
2853 bool bad_class_name = false;
2854 const char* other_pkg =
2855 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2856 if (bad_class_name) {
2857 return false;
2858 }
2859 // Check that package_from_name() returns NULL, not "", if there is no package.
2860 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2861
2862 const Symbol* const this_package_name =
2863 this->package() != NULL ? this->package()->name() : NULL;
2864
2865 if (this_package_name == NULL || other_pkg == NULL) {
2866 // One of the two doesn't have a package. Only return true if the other
2867 // one also doesn't have a package.
2868 return (const char*)this_package_name == other_pkg;
2869 }
2870
2871 // Check if package is identical
2872 return this_package_name->equals(other_pkg);
2873 }
2874 }
2875
2876 // Returns true iff super_method can be overridden by a method in targetclassname
2877 // See JLS 3rd edition 8.4.6.1
2878 // Assumes name-signature match
2879 // "this" is InstanceKlass of super_method which must exist
2880 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2881 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2882 // Private methods can not be overridden
2883 if (super_method->is_private()) {
2884 return false;
2885 }
2886 // If super method is accessible, then override
2887 if ((super_method->is_protected()) ||
2888 (super_method->is_public())) {
2889 return true;
2890 }
2891 // Package-private methods are not inherited outside of package
2892 assert(super_method->is_package_private(), "must be package private");
2893 return(is_same_class_package(targetclassloader(), targetclassname));
2894 }
2895
2896 // Only boot and platform class loaders can define classes in "java/" packages.
2897 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2898 ClassLoaderData* loader_data,
2899 TRAPS) {
2900 if (!loader_data->is_boot_class_loader_data() &&
2901 !loader_data->is_platform_class_loader_data() &&
2902 class_name != NULL) {
2903 ResourceMark rm(THREAD);
2904 char* name = class_name->as_C_string();
2905 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2906 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2907 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2908 name = pkg_name->as_C_string();
2909 const char* class_loader_name = loader_data->loader_name_and_id();
2910 StringUtils::replace_no_expand(name, "/", ".");
2911 const char* msg_text1 = "Class loader (instance of): ";
2912 const char* msg_text2 = " tried to load prohibited package name: ";
2913 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2914 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2915 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2916 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2917 }
2918 }
2919 return;
2920 }
2921
2922 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2923 constantPoolHandle i_cp(THREAD, constants());
2924 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2925 int ioff = iter.inner_class_info_index();
2926 if (ioff != 0) {
2927 // Check to see if the name matches the class we're looking for
2928 // before attempting to find the class.
2929 if (i_cp->klass_name_at_matches(this, ioff)) {
2930 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2931 if (this == inner_klass) {
2932 *ooff = iter.outer_class_info_index();
2933 *noff = iter.inner_name_index();
2934 return true;
2935 }
2936 }
2937 }
2938 }
2939 return false;
2940 }
2941
2942 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2943 InstanceKlass* outer_klass = NULL;
2944 *inner_is_member = false;
2945 int ooff = 0, noff = 0;
2946 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2947 if (has_inner_classes_attr) {
2948 constantPoolHandle i_cp(THREAD, constants());
2949 if (ooff != 0) {
2950 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2951 outer_klass = InstanceKlass::cast(ok);
2952 *inner_is_member = true;
2953 }
2954 if (NULL == outer_klass) {
2955 // It may be a local or anonymous class; try for that.
2956 int encl_method_class_idx = enclosing_method_class_index();
2957 if (encl_method_class_idx != 0) {
2958 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2959 outer_klass = InstanceKlass::cast(ok);
2960 *inner_is_member = false;
2961 }
2962 }
2963 }
2964
2965 // If no inner class attribute found for this class.
2966 if (NULL == outer_klass) return NULL;
2967
2968 // Throws an exception if outer klass has not declared k as an inner klass
2969 // We need evidence that each klass knows about the other, or else
2970 // the system could allow a spoof of an inner class to gain access rights.
2971 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2972 return outer_klass;
2973 }
2974
2975 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2976 jint access = access_flags().as_int();
2977
2978 // But check if it happens to be member class.
2979 InnerClassesIterator iter(this);
2980 for (; !iter.done(); iter.next()) {
2981 int ioff = iter.inner_class_info_index();
2982 // Inner class attribute can be zero, skip it.
2983 // Strange but true: JVM spec. allows null inner class refs.
2984 if (ioff == 0) continue;
2985
2986 // only look at classes that are already loaded
2987 // since we are looking for the flags for our self.
2988 Symbol* inner_name = constants()->klass_name_at(ioff);
2989 if (name() == inner_name) {
2990 // This is really a member class.
2991 access = iter.inner_access_flags();
2992 break;
2993 }
2994 }
2995 // Remember to strip ACC_SUPER bit
2996 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2997 }
2998
2999 jint InstanceKlass::jvmti_class_status() const {
3000 jint result = 0;
3001
3002 if (is_linked()) {
3003 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3004 }
3005
3006 if (is_initialized()) {
3007 assert(is_linked(), "Class status is not consistent");
3008 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3009 }
3010 if (is_in_error_state()) {
3011 result |= JVMTI_CLASS_STATUS_ERROR;
3012 }
3013 return result;
3014 }
3015
3016 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
3017 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
3018 int method_table_offset_in_words = ioe->offset()/wordSize;
3019 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
3020 / itableOffsetEntry::size();
3021
3022 for (int cnt = 0 ; ; cnt ++, ioe ++) {
3023 // If the interface isn't implemented by the receiver class,
3024 // the VM should throw IncompatibleClassChangeError.
3025 if (cnt >= nof_interfaces) {
3026 ResourceMark rm(THREAD);
3027 stringStream ss;
3028 bool same_module = (module() == holder->module());
3029 ss.print("Receiver class %s does not implement "
3030 "the interface %s defining the method to be called "
3031 "(%s%s%s)",
3032 external_name(), holder->external_name(),
3033 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3034 (same_module) ? "" : "; ",
3035 (same_module) ? "" : holder->class_in_module_of_loader());
3036 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3037 }
3038
3039 Klass* ik = ioe->interface_klass();
3040 if (ik == holder) break;
3041 }
3042
3043 itableMethodEntry* ime = ioe->first_method_entry(this);
3044 Method* m = ime[index].method();
3045 if (m == NULL) {
3046 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3047 }
3048 return m;
3049 }
3050
3051
3052 #if INCLUDE_JVMTI
3053 // update default_methods for redefineclasses for methods that are
3054 // not yet in the vtable due to concurrent subclass define and superinterface
3055 // redefinition
3056 // Note: those in the vtable, should have been updated via adjust_method_entries
3057 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3058 // search the default_methods for uses of either obsolete or EMCP methods
3059 if (default_methods() != NULL) {
3060 for (int index = 0; index < default_methods()->length(); index ++) {
3061 Method* old_method = default_methods()->at(index);
3062 if (old_method == NULL || !old_method->is_old()) {
3063 continue; // skip uninteresting entries
3064 }
3065 assert(!old_method->is_deleted(), "default methods may not be deleted");
3066 Method* new_method = old_method->get_new_method();
3067 default_methods()->at_put(index, new_method);
3068
3069 if (log_is_enabled(Info, redefine, class, update)) {
3070 ResourceMark rm;
3071 if (!(*trace_name_printed)) {
3072 log_info(redefine, class, update)
3073 ("adjust: klassname=%s default methods from name=%s",
3074 external_name(), old_method->method_holder()->external_name());
3075 *trace_name_printed = true;
3076 }
3077 log_debug(redefine, class, update, vtables)
3078 ("default method update: %s(%s) ",
3079 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3080 }
3081 }
3082 }
3083 }
3084 #endif // INCLUDE_JVMTI
3085
3086 // On-stack replacement stuff
3087 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3088 assert_lock_strong(CompiledMethod_lock);
3089 #ifndef PRODUCT
3090 if (TieredCompilation) {
3091 nmethod * prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3092 assert(prev == NULL || !prev->is_in_use(),
3093 "redundunt OSR recompilation detected. memory leak in CodeCache!");
3094 }
3095 #endif
3096 // only one compilation can be active
3097 {
3098 assert(n->is_osr_method(), "wrong kind of nmethod");
3099 n->set_osr_link(osr_nmethods_head());
3100 set_osr_nmethods_head(n);
3101 // Raise the highest osr level if necessary
3102 if (TieredCompilation) {
3103 Method* m = n->method();
3104 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
3105 }
3106 }
3107
3108 // Get rid of the osr methods for the same bci that have lower levels.
3109 if (TieredCompilation) {
3110 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3111 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3112 if (inv != NULL && inv->is_in_use()) {
3113 inv->make_not_entrant();
3114 }
3115 }
3116 }
3117 }
3118
3119 // Remove osr nmethod from the list. Return true if found and removed.
3120 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3121 // This is a short non-blocking critical region, so the no safepoint check is ok.
3122 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock
3123 , Mutex::_no_safepoint_check_flag);
3124 assert(n->is_osr_method(), "wrong kind of nmethod");
3125 nmethod* last = NULL;
3126 nmethod* cur = osr_nmethods_head();
3127 int max_level = CompLevel_none; // Find the max comp level excluding n
3128 Method* m = n->method();
3129 // Search for match
3130 bool found = false;
3131 while(cur != NULL && cur != n) {
3132 if (TieredCompilation && m == cur->method()) {
3133 // Find max level before n
3134 max_level = MAX2(max_level, cur->comp_level());
3135 }
3136 last = cur;
3137 cur = cur->osr_link();
3138 }
3139 nmethod* next = NULL;
3140 if (cur == n) {
3141 found = true;
3142 next = cur->osr_link();
3143 if (last == NULL) {
3144 // Remove first element
3145 set_osr_nmethods_head(next);
3146 } else {
3147 last->set_osr_link(next);
3148 }
3149 }
3150 n->set_osr_link(NULL);
3151 if (TieredCompilation) {
3152 cur = next;
3153 while (cur != NULL) {
3154 // Find max level after n
3155 if (m == cur->method()) {
3156 max_level = MAX2(max_level, cur->comp_level());
3157 }
3158 cur = cur->osr_link();
3159 }
3160 m->set_highest_osr_comp_level(max_level);
3161 }
3162 return found;
3163 }
3164
3165 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3166 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3167 Mutex::_no_safepoint_check_flag);
3168 nmethod* osr = osr_nmethods_head();
3169 int found = 0;
3170 while (osr != NULL) {
3171 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3172 if (osr->method() == m) {
3173 osr->mark_for_deoptimization();
3174 found++;
3175 }
3176 osr = osr->osr_link();
3177 }
3178 return found;
3179 }
3180
3181 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3182 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3183 Mutex::_no_safepoint_check_flag);
3184 nmethod* osr = osr_nmethods_head();
3185 nmethod* best = NULL;
3186 while (osr != NULL) {
3187 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3188 // There can be a time when a c1 osr method exists but we are waiting
3189 // for a c2 version. When c2 completes its osr nmethod we will trash
3190 // the c1 version and only be able to find the c2 version. However
3191 // while we overflow in the c1 code at back branches we don't want to
3192 // try and switch to the same code as we are already running
3193
3194 if (osr->method() == m &&
3195 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3196 if (match_level) {
3197 if (osr->comp_level() == comp_level) {
3198 // Found a match - return it.
3199 return osr;
3200 }
3201 } else {
3202 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3203 if (osr->comp_level() == CompLevel_highest_tier) {
3204 // Found the best possible - return it.
3205 return osr;
3206 }
3207 best = osr;
3208 }
3209 }
3210 }
3211 osr = osr->osr_link();
3212 }
3213
3214 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set");
3215 if (best != NULL && best->comp_level() >= comp_level) {
3216 return best;
3217 }
3218 return NULL;
3219 }
3220
3221 // -----------------------------------------------------------------------------------------------------
3222 // Printing
3223
3224 #ifndef PRODUCT
3225
3226 #define BULLET " - "
3227
3228 static const char* state_names[] = {
3229 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3230 };
3231
3232 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3233 for (int i = 0; i < len; i++) {
3234 intptr_t e = start[i];
3235 st->print("%d : " INTPTR_FORMAT, i, e);
3236 if (MetaspaceObj::is_valid((Metadata*)e)) {
3237 st->print(" ");
3238 ((Metadata*)e)->print_value_on(st);
3239 }
3240 st->cr();
3241 }
3242 }
3243
3244 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3245 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3246 }
3247
3248 void InstanceKlass::print_on(outputStream* st) const {
3249 assert(is_klass(), "must be klass");
3250 Klass::print_on(st);
3251
3252 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3253 st->print(BULLET"klass size: %d", size()); st->cr();
3254 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3255 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3256 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3257 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3258 st->print(BULLET"sub: ");
3259 Klass* sub = subklass();
3260 int n;
3261 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3262 if (n < MaxSubklassPrintSize) {
3263 sub->print_value_on(st);
3264 st->print(" ");
3265 }
3266 }
3267 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3268 st->cr();
3269
3270 if (is_interface()) {
3271 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3272 if (nof_implementors() == 1) {
3273 st->print_cr(BULLET"implementor: ");
3274 st->print(" ");
3275 implementor()->print_value_on(st);
3276 st->cr();
3277 }
3278 }
3279
3280 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3281 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3282 if (Verbose || WizardMode) {
3283 Array<Method*>* method_array = methods();
3284 for (int i = 0; i < method_array->length(); i++) {
3285 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3286 }
3287 }
3288 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3289 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3290 if (Verbose && default_methods() != NULL) {
3291 Array<Method*>* method_array = default_methods();
3292 for (int i = 0; i < method_array->length(); i++) {
3293 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3294 }
3295 }
3296 if (default_vtable_indices() != NULL) {
3297 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3298 }
3299 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3300 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3301 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3302 if (class_loader_data() != NULL) {
3303 st->print(BULLET"class loader data: ");
3304 class_loader_data()->print_value_on(st);
3305 st->cr();
3306 }
3307 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3308 if (source_file_name() != NULL) {
3309 st->print(BULLET"source file: ");
3310 source_file_name()->print_value_on(st);
3311 st->cr();
3312 }
3313 if (source_debug_extension() != NULL) {
3314 st->print(BULLET"source debug extension: ");
3315 st->print("%s", source_debug_extension());
3316 st->cr();
3317 }
3318 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3319 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3320 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3321 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3322 {
3323 bool have_pv = false;
3324 // previous versions are linked together through the InstanceKlass
3325 for (InstanceKlass* pv_node = previous_versions();
3326 pv_node != NULL;
3327 pv_node = pv_node->previous_versions()) {
3328 if (!have_pv)
3329 st->print(BULLET"previous version: ");
3330 have_pv = true;
3331 pv_node->constants()->print_value_on(st);
3332 }
3333 if (have_pv) st->cr();
3334 }
3335
3336 if (generic_signature() != NULL) {
3337 st->print(BULLET"generic signature: ");
3338 generic_signature()->print_value_on(st);
3339 st->cr();
3340 }
3341 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3342 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3343 if (record_components() != NULL) {
3344 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3345 }
3346 if (java_mirror() != NULL) {
3347 st->print(BULLET"java mirror: ");
3348 java_mirror()->print_value_on(st);
3349 st->cr();
3350 } else {
3351 st->print_cr(BULLET"java mirror: NULL");
3352 }
3353 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3354 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3355 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3356 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3357 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3358 FieldPrinter print_static_field(st);
3359 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3360 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3361 FieldPrinter print_nonstatic_field(st);
3362 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3363 ik->do_nonstatic_fields(&print_nonstatic_field);
3364
3365 st->print(BULLET"non-static oop maps: ");
3366 OopMapBlock* map = start_of_nonstatic_oop_maps();
3367 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3368 while (map < end_map) {
3369 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3370 map++;
3371 }
3372 st->cr();
3373 }
3374
3375 #endif //PRODUCT
3376
3377 void InstanceKlass::print_value_on(outputStream* st) const {
3378 assert(is_klass(), "must be klass");
3379 if (Verbose || WizardMode) access_flags().print_on(st);
3380 name()->print_value_on(st);
3381 }
3382
3383 #ifndef PRODUCT
3384
3385 void FieldPrinter::do_field(fieldDescriptor* fd) {
3386 _st->print(BULLET);
3387 if (_obj == NULL) {
3388 fd->print_on(_st);
3389 _st->cr();
3390 } else {
3391 fd->print_on_for(_st, _obj);
3392 _st->cr();
3393 }
3394 }
3395
3396
3397 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3398 Klass::oop_print_on(obj, st);
3399
3400 if (this == SystemDictionary::String_klass()) {
3401 typeArrayOop value = java_lang_String::value(obj);
3402 juint length = java_lang_String::length(obj);
3403 if (value != NULL &&
3404 value->is_typeArray() &&
3405 length <= (juint) value->length()) {
3406 st->print(BULLET"string: ");
3407 java_lang_String::print(obj, st);
3408 st->cr();
3409 if (!WizardMode) return; // that is enough
3410 }
3411 }
3412
3413 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3414 FieldPrinter print_field(st, obj);
3415 do_nonstatic_fields(&print_field);
3416
3417 if (this == SystemDictionary::Class_klass()) {
3418 st->print(BULLET"signature: ");
3419 java_lang_Class::print_signature(obj, st);
3420 st->cr();
3421 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3422 st->print(BULLET"fake entry for mirror: ");
3423 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3424 st->cr();
3425 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3426 st->print(BULLET"fake entry for array: ");
3427 Metadata::print_value_on_maybe_null(st, array_klass);
3428 st->cr();
3429 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3430 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3431 Klass* real_klass = java_lang_Class::as_Klass(obj);
3432 if (real_klass != NULL && real_klass->is_instance_klass()) {
3433 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3434 }
3435 } else if (this == SystemDictionary::MethodType_klass()) {
3436 st->print(BULLET"signature: ");
3437 java_lang_invoke_MethodType::print_signature(obj, st);
3438 st->cr();
3439 }
3440 }
3441
3442 bool InstanceKlass::verify_itable_index(int i) {
3443 int method_count = klassItable::method_count_for_interface(this);
3444 assert(i >= 0 && i < method_count, "index out of bounds");
3445 return true;
3446 }
3447
3448 #endif //PRODUCT
3449
3450 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3451 st->print("a ");
3452 name()->print_value_on(st);
3453 obj->print_address_on(st);
3454 if (this == SystemDictionary::String_klass()
3455 && java_lang_String::value(obj) != NULL) {
3456 ResourceMark rm;
3457 int len = java_lang_String::length(obj);
3458 int plen = (len < 24 ? len : 12);
3459 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3460 st->print(" = \"%s\"", str);
3461 if (len > plen)
3462 st->print("...[%d]", len);
3463 } else if (this == SystemDictionary::Class_klass()) {
3464 Klass* k = java_lang_Class::as_Klass(obj);
3465 st->print(" = ");
3466 if (k != NULL) {
3467 k->print_value_on(st);
3468 } else {
3469 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3470 st->print("%s", tname ? tname : "type?");
3471 }
3472 } else if (this == SystemDictionary::MethodType_klass()) {
3473 st->print(" = ");
3474 java_lang_invoke_MethodType::print_signature(obj, st);
3475 } else if (java_lang_boxing_object::is_instance(obj)) {
3476 st->print(" = ");
3477 java_lang_boxing_object::print(obj, st);
3478 } else if (this == SystemDictionary::LambdaForm_klass()) {
3479 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3480 if (vmentry != NULL) {
3481 st->print(" => ");
3482 vmentry->print_value_on(st);
3483 }
3484 } else if (this == SystemDictionary::MemberName_klass()) {
3485 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3486 if (vmtarget != NULL) {
3487 st->print(" = ");
3488 vmtarget->print_value_on(st);
3489 } else {
3490 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3491 st->print(".");
3492 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3493 }
3494 }
3495 }
3496
3497 const char* InstanceKlass::internal_name() const {
3498 return external_name();
3499 }
3500
3501 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3502 const char* module_name,
3503 const ClassFileStream* cfs) const {
3504 if (!log_is_enabled(Info, class, load)) {
3505 return;
3506 }
3507
3508 ResourceMark rm;
3509 LogMessage(class, load) msg;
3510 stringStream info_stream;
3511
3512 // Name and class hierarchy info
3513 info_stream.print("%s", external_name());
3514
3515 // Source
3516 if (cfs != NULL) {
3517 if (cfs->source() != NULL) {
3518 if (module_name != NULL) {
3519 // When the boot loader created the stream, it didn't know the module name
3520 // yet. Let's format it now.
3521 if (cfs->from_boot_loader_modules_image()) {
3522 info_stream.print(" source: jrt:/%s", module_name);
3523 } else {
3524 info_stream.print(" source: %s", cfs->source());
3525 }
3526 } else {
3527 info_stream.print(" source: %s", cfs->source());
3528 }
3529 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3530 Thread* THREAD = Thread::current();
3531 Klass* caller =
3532 THREAD->is_Java_thread()
3533 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3534 : NULL;
3535 // caller can be NULL, for example, during a JVMTI VM_Init hook
3536 if (caller != NULL) {
3537 info_stream.print(" source: instance of %s", caller->external_name());
3538 } else {
3539 // source is unknown
3540 }
3541 } else {
3542 oop class_loader = loader_data->class_loader();
3543 info_stream.print(" source: %s", class_loader->klass()->external_name());
3544 }
3545 } else {
3546 assert(this->is_shared(), "must be");
3547 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3548 info_stream.print(" source: shared objects file (top)");
3549 } else {
3550 info_stream.print(" source: shared objects file");
3551 }
3552 }
3553
3554 msg.info("%s", info_stream.as_string());
3555
3556 if (log_is_enabled(Debug, class, load)) {
3557 stringStream debug_stream;
3558
3559 // Class hierarchy info
3560 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3561 p2i(this), p2i(superklass()));
3562
3563 // Interfaces
3564 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3565 debug_stream.print(" interfaces:");
3566 int length = local_interfaces()->length();
3567 for (int i = 0; i < length; i++) {
3568 debug_stream.print(" " INTPTR_FORMAT,
3569 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3570 }
3571 }
3572
3573 // Class loader
3574 debug_stream.print(" loader: [");
3575 loader_data->print_value_on(&debug_stream);
3576 debug_stream.print("]");
3577
3578 // Classfile checksum
3579 if (cfs) {
3580 debug_stream.print(" bytes: %d checksum: %08x",
3581 cfs->length(),
3582 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3583 cfs->length()));
3584 }
3585
3586 msg.debug("%s", debug_stream.as_string());
3587 }
3588 }
3589
3590 // Verification
3591
3592 class VerifyFieldClosure: public BasicOopIterateClosure {
3593 protected:
3594 template <class T> void do_oop_work(T* p) {
3595 oop obj = RawAccess<>::oop_load(p);
3596 if (!oopDesc::is_oop_or_null(obj)) {
3597 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3598 Universe::print_on(tty);
3599 guarantee(false, "boom");
3600 }
3601 }
3602 public:
3603 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3604 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3605 };
3606
3607 void InstanceKlass::verify_on(outputStream* st) {
3608 #ifndef PRODUCT
3609 // Avoid redundant verifies, this really should be in product.
3610 if (_verify_count == Universe::verify_count()) return;
3611 _verify_count = Universe::verify_count();
3612 #endif
3613
3614 // Verify Klass
3615 Klass::verify_on(st);
3616
3617 // Verify that klass is present in ClassLoaderData
3618 guarantee(class_loader_data()->contains_klass(this),
3619 "this class isn't found in class loader data");
3620
3621 // Verify vtables
3622 if (is_linked()) {
3623 // $$$ This used to be done only for m/s collections. Doing it
3624 // always seemed a valid generalization. (DLD -- 6/00)
3625 vtable().verify(st);
3626 }
3627
3628 // Verify first subklass
3629 if (subklass() != NULL) {
3630 guarantee(subklass()->is_klass(), "should be klass");
3631 }
3632
3633 // Verify siblings
3634 Klass* super = this->super();
3635 Klass* sib = next_sibling();
3636 if (sib != NULL) {
3637 if (sib == this) {
3638 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3639 }
3640
3641 guarantee(sib->is_klass(), "should be klass");
3642 guarantee(sib->super() == super, "siblings should have same superklass");
3643 }
3644
3645 // Verify local interfaces
3646 if (local_interfaces()) {
3647 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3648 for (int j = 0; j < local_interfaces->length(); j++) {
3649 InstanceKlass* e = local_interfaces->at(j);
3650 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3651 }
3652 }
3653
3654 // Verify transitive interfaces
3655 if (transitive_interfaces() != NULL) {
3656 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3657 for (int j = 0; j < transitive_interfaces->length(); j++) {
3658 InstanceKlass* e = transitive_interfaces->at(j);
3659 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3660 }
3661 }
3662
3663 // Verify methods
3664 if (methods() != NULL) {
3665 Array<Method*>* methods = this->methods();
3666 for (int j = 0; j < methods->length(); j++) {
3667 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3668 }
3669 for (int j = 0; j < methods->length() - 1; j++) {
3670 Method* m1 = methods->at(j);
3671 Method* m2 = methods->at(j + 1);
3672 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3673 }
3674 }
3675
3676 // Verify method ordering
3677 if (method_ordering() != NULL) {
3678 Array<int>* method_ordering = this->method_ordering();
3679 int length = method_ordering->length();
3680 if (JvmtiExport::can_maintain_original_method_order() ||
3681 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
3682 guarantee(length == methods()->length(), "invalid method ordering length");
3683 jlong sum = 0;
3684 for (int j = 0; j < length; j++) {
3685 int original_index = method_ordering->at(j);
3686 guarantee(original_index >= 0, "invalid method ordering index");
3687 guarantee(original_index < length, "invalid method ordering index");
3688 sum += original_index;
3689 }
3690 // Verify sum of indices 0,1,...,length-1
3691 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3692 } else {
3693 guarantee(length == 0, "invalid method ordering length");
3694 }
3695 }
3696
3697 // Verify default methods
3698 if (default_methods() != NULL) {
3699 Array<Method*>* methods = this->default_methods();
3700 for (int j = 0; j < methods->length(); j++) {
3701 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3702 }
3703 for (int j = 0; j < methods->length() - 1; j++) {
3704 Method* m1 = methods->at(j);
3705 Method* m2 = methods->at(j + 1);
3706 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3707 }
3708 }
3709
3710 // Verify JNI static field identifiers
3711 if (jni_ids() != NULL) {
3712 jni_ids()->verify(this);
3713 }
3714
3715 // Verify other fields
3716 if (array_klasses() != NULL) {
3717 guarantee(array_klasses()->is_klass(), "should be klass");
3718 }
3719 if (constants() != NULL) {
3720 guarantee(constants()->is_constantPool(), "should be constant pool");
3721 }
3722 const Klass* anonymous_host = unsafe_anonymous_host();
3723 if (anonymous_host != NULL) {
3724 guarantee(anonymous_host->is_klass(), "should be klass");
3725 }
3726 }
3727
3728 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3729 Klass::oop_verify_on(obj, st);
3730 VerifyFieldClosure blk;
3731 obj->oop_iterate(&blk);
3732 }
3733
3734
3735 // JNIid class for jfieldIDs only
3736 // Note to reviewers:
3737 // These JNI functions are just moved over to column 1 and not changed
3738 // in the compressed oops workspace.
3739 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3740 _holder = holder;
3741 _offset = offset;
3742 _next = next;
3743 debug_only(_is_static_field_id = false;)
3744 }
3745
3746
3747 JNIid* JNIid::find(int offset) {
3748 JNIid* current = this;
3749 while (current != NULL) {
3750 if (current->offset() == offset) return current;
3751 current = current->next();
3752 }
3753 return NULL;
3754 }
3755
3756 void JNIid::deallocate(JNIid* current) {
3757 while (current != NULL) {
3758 JNIid* next = current->next();
3759 delete current;
3760 current = next;
3761 }
3762 }
3763
3764
3765 void JNIid::verify(Klass* holder) {
3766 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3767 int end_field_offset;
3768 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3769
3770 JNIid* current = this;
3771 while (current != NULL) {
3772 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3773 #ifdef ASSERT
3774 int o = current->offset();
3775 if (current->is_static_field_id()) {
3776 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3777 }
3778 #endif
3779 current = current->next();
3780 }
3781 }
3782
3783 void InstanceKlass::set_init_state(ClassState state) {
3784 #ifdef ASSERT
3785 bool good_state = is_shared() ? (_init_state <= state)
3786 : (_init_state < state);
3787 assert(good_state || state == allocated, "illegal state transition");
3788 #endif
3789 assert(_init_thread == NULL, "should be cleared before state change");
3790 _init_state = (u1)state;
3791 }
3792
3793 #if INCLUDE_JVMTI
3794
3795 // RedefineClasses() support for previous versions
3796
3797 // Globally, there is at least one previous version of a class to walk
3798 // during class unloading, which is saved because old methods in the class
3799 // are still running. Otherwise the previous version list is cleaned up.
3800 bool InstanceKlass::_has_previous_versions = false;
3801
3802 // Returns true if there are previous versions of a class for class
3803 // unloading only. Also resets the flag to false. purge_previous_version
3804 // will set the flag to true if there are any left, i.e., if there's any
3805 // work to do for next time. This is to avoid the expensive code cache
3806 // walk in CLDG::clean_deallocate_lists().
3807 bool InstanceKlass::has_previous_versions_and_reset() {
3808 bool ret = _has_previous_versions;
3809 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3810 ret ? "true" : "false");
3811 _has_previous_versions = false;
3812 return ret;
3813 }
3814
3815 // Purge previous versions before adding new previous versions of the class and
3816 // during class unloading.
3817 void InstanceKlass::purge_previous_version_list() {
3818 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3819 assert(has_been_redefined(), "Should only be called for main class");
3820
3821 // Quick exit.
3822 if (previous_versions() == NULL) {
3823 return;
3824 }
3825
3826 // This klass has previous versions so see what we can cleanup
3827 // while it is safe to do so.
3828
3829 int deleted_count = 0; // leave debugging breadcrumbs
3830 int live_count = 0;
3831 ClassLoaderData* loader_data = class_loader_data();
3832 assert(loader_data != NULL, "should never be null");
3833
3834 ResourceMark rm;
3835 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3836
3837 // previous versions are linked together through the InstanceKlass
3838 InstanceKlass* pv_node = previous_versions();
3839 InstanceKlass* last = this;
3840 int version = 0;
3841
3842 // check the previous versions list
3843 for (; pv_node != NULL; ) {
3844
3845 ConstantPool* pvcp = pv_node->constants();
3846 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3847
3848 if (!pvcp->on_stack()) {
3849 // If the constant pool isn't on stack, none of the methods
3850 // are executing. Unlink this previous_version.
3851 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3852 // so will be deallocated during the next phase of class unloading.
3853 log_trace(redefine, class, iklass, purge)
3854 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3855 // For debugging purposes.
3856 pv_node->set_is_scratch_class();
3857 // Unlink from previous version list.
3858 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3859 InstanceKlass* next = pv_node->previous_versions();
3860 pv_node->link_previous_versions(NULL); // point next to NULL
3861 last->link_previous_versions(next);
3862 // Add to the deallocate list after unlinking
3863 loader_data->add_to_deallocate_list(pv_node);
3864 pv_node = next;
3865 deleted_count++;
3866 version++;
3867 continue;
3868 } else {
3869 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3870 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3871 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3872 live_count++;
3873 // found a previous version for next time we do class unloading
3874 _has_previous_versions = true;
3875 }
3876
3877 // At least one method is live in this previous version.
3878 // Reset dead EMCP methods not to get breakpoints.
3879 // All methods are deallocated when all of the methods for this class are no
3880 // longer running.
3881 Array<Method*>* method_refs = pv_node->methods();
3882 if (method_refs != NULL) {
3883 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3884 for (int j = 0; j < method_refs->length(); j++) {
3885 Method* method = method_refs->at(j);
3886
3887 if (!method->on_stack()) {
3888 // no breakpoints for non-running methods
3889 if (method->is_running_emcp()) {
3890 method->set_running_emcp(false);
3891 }
3892 } else {
3893 assert (method->is_obsolete() || method->is_running_emcp(),
3894 "emcp method cannot run after emcp bit is cleared");
3895 log_trace(redefine, class, iklass, purge)
3896 ("purge: %s(%s): prev method @%d in version @%d is alive",
3897 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3898 }
3899 }
3900 }
3901 // next previous version
3902 last = pv_node;
3903 pv_node = pv_node->previous_versions();
3904 version++;
3905 }
3906 log_trace(redefine, class, iklass, purge)
3907 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3908 }
3909
3910 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3911 int emcp_method_count) {
3912 int obsolete_method_count = old_methods->length() - emcp_method_count;
3913
3914 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3915 _previous_versions != NULL) {
3916 // We have a mix of obsolete and EMCP methods so we have to
3917 // clear out any matching EMCP method entries the hard way.
3918 int local_count = 0;
3919 for (int i = 0; i < old_methods->length(); i++) {
3920 Method* old_method = old_methods->at(i);
3921 if (old_method->is_obsolete()) {
3922 // only obsolete methods are interesting
3923 Symbol* m_name = old_method->name();
3924 Symbol* m_signature = old_method->signature();
3925
3926 // previous versions are linked together through the InstanceKlass
3927 int j = 0;
3928 for (InstanceKlass* prev_version = _previous_versions;
3929 prev_version != NULL;
3930 prev_version = prev_version->previous_versions(), j++) {
3931
3932 Array<Method*>* method_refs = prev_version->methods();
3933 for (int k = 0; k < method_refs->length(); k++) {
3934 Method* method = method_refs->at(k);
3935
3936 if (!method->is_obsolete() &&
3937 method->name() == m_name &&
3938 method->signature() == m_signature) {
3939 // The current RedefineClasses() call has made all EMCP
3940 // versions of this method obsolete so mark it as obsolete
3941 log_trace(redefine, class, iklass, add)
3942 ("%s(%s): flush obsolete method @%d in version @%d",
3943 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3944
3945 method->set_is_obsolete();
3946 break;
3947 }
3948 }
3949
3950 // The previous loop may not find a matching EMCP method, but
3951 // that doesn't mean that we can optimize and not go any
3952 // further back in the PreviousVersion generations. The EMCP
3953 // method for this generation could have already been made obsolete,
3954 // but there still may be an older EMCP method that has not
3955 // been made obsolete.
3956 }
3957
3958 if (++local_count >= obsolete_method_count) {
3959 // no more obsolete methods so bail out now
3960 break;
3961 }
3962 }
3963 }
3964 }
3965 }
3966
3967 // Save the scratch_class as the previous version if any of the methods are running.
3968 // The previous_versions are used to set breakpoints in EMCP methods and they are
3969 // also used to clean MethodData links to redefined methods that are no longer running.
3970 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3971 int emcp_method_count) {
3972 assert(Thread::current()->is_VM_thread(),
3973 "only VMThread can add previous versions");
3974
3975 ResourceMark rm;
3976 log_trace(redefine, class, iklass, add)
3977 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3978
3979 // Clean out old previous versions for this class
3980 purge_previous_version_list();
3981
3982 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3983 // a previous redefinition may be made obsolete by this redefinition.
3984 Array<Method*>* old_methods = scratch_class->methods();
3985 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3986
3987 // If the constant pool for this previous version of the class
3988 // is not marked as being on the stack, then none of the methods
3989 // in this previous version of the class are on the stack so
3990 // we don't need to add this as a previous version.
3991 ConstantPool* cp_ref = scratch_class->constants();
3992 if (!cp_ref->on_stack()) {
3993 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3994 // For debugging purposes.
3995 scratch_class->set_is_scratch_class();
3996 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3997 return;
3998 }
3999
4000 if (emcp_method_count != 0) {
4001 // At least one method is still running, check for EMCP methods
4002 for (int i = 0; i < old_methods->length(); i++) {
4003 Method* old_method = old_methods->at(i);
4004 if (!old_method->is_obsolete() && old_method->on_stack()) {
4005 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
4006 // we can add breakpoints for it.
4007
4008 // We set the method->on_stack bit during safepoints for class redefinition
4009 // and use this bit to set the is_running_emcp bit.
4010 // After the safepoint, the on_stack bit is cleared and the running emcp
4011 // method may exit. If so, we would set a breakpoint in a method that
4012 // is never reached, but this won't be noticeable to the programmer.
4013 old_method->set_running_emcp(true);
4014 log_trace(redefine, class, iklass, add)
4015 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
4016 } else if (!old_method->is_obsolete()) {
4017 log_trace(redefine, class, iklass, add)
4018 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
4019 }
4020 }
4021 }
4022
4023 // Add previous version if any methods are still running.
4024 // Set has_previous_version flag for processing during class unloading.
4025 _has_previous_versions = true;
4026 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4027 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
4028 scratch_class->link_previous_versions(previous_versions());
4029 link_previous_versions(scratch_class);
4030 } // end add_previous_version()
4031
4032 #endif // INCLUDE_JVMTI
4033
4034 Method* InstanceKlass::method_with_idnum(int idnum) {
4035 Method* m = NULL;
4036 if (idnum < methods()->length()) {
4037 m = methods()->at(idnum);
4038 }
4039 if (m == NULL || m->method_idnum() != idnum) {
4040 for (int index = 0; index < methods()->length(); ++index) {
4041 m = methods()->at(index);
4042 if (m->method_idnum() == idnum) {
4043 return m;
4044 }
4045 }
4046 // None found, return null for the caller to handle.
4047 return NULL;
4048 }
4049 return m;
4050 }
4051
4052
4053 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4054 if (idnum >= methods()->length()) {
4055 return NULL;
4056 }
4057 Method* m = methods()->at(idnum);
4058 if (m != NULL && m->orig_method_idnum() == idnum) {
4059 return m;
4060 }
4061 // Obsolete method idnum does not match the original idnum
4062 for (int index = 0; index < methods()->length(); ++index) {
4063 m = methods()->at(index);
4064 if (m->orig_method_idnum() == idnum) {
4065 return m;
4066 }
4067 }
4068 // None found, return null for the caller to handle.
4069 return NULL;
4070 }
4071
4072
4073 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4074 InstanceKlass* holder = get_klass_version(version);
4075 if (holder == NULL) {
4076 return NULL; // The version of klass is gone, no method is found
4077 }
4078 Method* method = holder->method_with_orig_idnum(idnum);
4079 return method;
4080 }
4081
4082 #if INCLUDE_JVMTI
4083 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4084 return _cached_class_file;
4085 }
4086
4087 jint InstanceKlass::get_cached_class_file_len() {
4088 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4089 }
4090
4091 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4092 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4093 }
4094 #endif