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