1 /*
2 * Copyright (c) 1997, 2018, 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/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/verifier.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/dependencyContext.hpp"
39 #include "compiler/compileBroker.hpp"
40 #include "gc/shared/collectedHeap.inline.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/heapInspection.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 "oops/fieldStreams.hpp"
56 #include "oops/instanceClassLoaderKlass.hpp"
57 #include "oops/instanceKlass.inline.hpp"
58 #include "oops/instanceMirrorKlass.hpp"
59 #include "oops/instanceOop.hpp"
60 #include "oops/klass.inline.hpp"
61 #include "oops/method.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* clss_name = name(); \
100 if (clss_name != NULL) { \
101 data = (char*)clss_name->bytes(); \
102 len = clss_name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (void*)class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* clss_name = name(); \
113 if (clss_name != NULL) { \
114 data = (char*)clss_name->bytes(); \
115 len = clss_name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (void*)class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 static inline bool is_class_loader(const Symbol* class_name,
129 const ClassFileParser& parser) {
130 assert(class_name != NULL, "invariant");
131
132 if (class_name == vmSymbols::java_lang_ClassLoader()) {
133 return true;
134 }
135
136 if (SystemDictionary::ClassLoader_klass_loaded()) {
137 const Klass* const super_klass = parser.super_klass();
138 if (super_klass != NULL) {
139 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
140 return true;
141 }
142 }
143 }
144 return false;
145 }
146
147 // called to verify that k is a member of this nest
148 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
149 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
150 if (log_is_enabled(Trace, class, nestmates)) {
151 ResourceMark rm(THREAD);
152 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
153 k->external_name(), this->external_name());
154 }
155 return false;
156 }
157
158 if (log_is_enabled(Trace, class, nestmates)) {
159 ResourceMark rm(THREAD);
160 log_trace(class, nestmates)("Checking nest membership of %s in %s",
161 k->external_name(), this->external_name());
162 }
163
164 // Check names first and if they match then check actual klass. This avoids
165 // resolving anything unnecessarily.
166 for (int i = 0; i < _nest_members->length(); i++) {
167 int cp_index = _nest_members->at(i);
168 Symbol* name = _constants->klass_name_at(cp_index);
169 if (name == k->name()) {
170 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
171
172 // names match so check actual klass - this may trigger class loading if
173 // it doesn't match (but that should be impossible)
174 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
175 if (k2 == k) {
176 log_trace(class, nestmates)("- class is listed as a nest member");
177 return true;
178 } else {
179 // same name but different klass!
180 log_trace(class, nestmates)(" - klass comparison failed!");
181 // can't have different classes for the same name, so we're done
182 return false;
183 }
184 }
185 }
186 log_trace(class, nestmates)("- class is NOT a nest member!");
187 return false;
188 }
189
190 // Return nest-host class, resolving, validating and saving it if needed.
191 // In cases where this is called from a thread that can not do classloading
192 // (such as a native JIT thread) then we simply return NULL, which in turn
193 // causes the access check to return false. Such code will retry the access
194 // from a more suitable environment later.
195 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
196 InstanceKlass* nest_host_k = _nest_host;
197 if (nest_host_k == NULL) {
198 // need to resolve and save our nest-host class. This could be attempted
199 // concurrently but as the result is idempotent and we don't use the class
200 // then we do not need any synchronization beyond what is implicitly used
201 // during class loading.
202 if (_nest_host_index != 0) { // we have a real nest_host
203 // Before trying to resolve check if we're in a suitable context
204 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
205 if (log_is_enabled(Trace, class, nestmates)) {
206 ResourceMark rm(THREAD);
207 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
208 this->external_name());
209 }
210 return NULL;
211 }
212
213 if (log_is_enabled(Trace, class, nestmates)) {
214 ResourceMark rm(THREAD);
215 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
216 this->external_name(),
217 _constants->klass_name_at(_nest_host_index)->as_C_string());
218 }
219
220 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
221 if (HAS_PENDING_EXCEPTION) {
222 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
223 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
224 // throw a new CDNFE with the original as its cause, and a clear msg
225 ResourceMark rm(THREAD);
226 char buf[200];
227 CLEAR_PENDING_EXCEPTION;
228 jio_snprintf(buf, sizeof(buf),
229 "Unable to load nest-host class (%s) of %s",
230 _constants->klass_name_at(_nest_host_index)->as_C_string(),
231 this->external_name());
232 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
233 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
234 }
235 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
236 return NULL;
237 }
238
239 // A valid nest-host is an instance class in the current package that lists this
240 // class as a nest member. If any of these conditions are not met we post the
241 // requested exception type (if any) and return NULL
242
243 const char* error = NULL;
244
245 // JVMS 5.4.4 indicates package check comes first
246 if (is_same_class_package(k)) {
247
248 // Now check actual membership. We can't be a member if our "host" is
249 // not an instance class.
250 if (k->is_instance_klass()) {
251 nest_host_k = InstanceKlass::cast(k);
252
253 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
254 if (is_member) {
255 // save resolved nest-host value
256 _nest_host = nest_host_k;
257
258 if (log_is_enabled(Trace, class, nestmates)) {
259 ResourceMark rm(THREAD);
260 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
261 this->external_name(), k->external_name());
262 }
263 return nest_host_k;
264 }
265 }
266 error = "current type is not listed as a nest member";
267 } else {
268 error = "types are in different packages";
269 }
270
271 if (log_is_enabled(Trace, class, nestmates)) {
272 ResourceMark rm(THREAD);
273 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
274 this->external_name(),
275 k->external_name(),
276 error);
277 }
278
279 if (validationException != NULL) {
280 ResourceMark rm(THREAD);
281 Exceptions::fthrow(THREAD_AND_LOCATION,
282 validationException,
283 "Type %s is not a nest member of %s: %s",
284 this->external_name(),
285 k->external_name(),
286 error
287 );
288 }
289 return NULL;
290 } else {
291 if (log_is_enabled(Trace, class, nestmates)) {
292 ResourceMark rm(THREAD);
293 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
294 this->external_name());
295 }
296 // save resolved nest-host value
297 return (_nest_host = this);
298 }
299 }
300 return nest_host_k;
301 }
302
303 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
304 // or we are k's nest_host - all of which is covered by comparing the two
305 // resolved_nest_hosts
306 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
307
308 assert(this != k, "this should be handled by higher-level code");
309
310 // Per JVMS 5.4.4 we first resolve and validate the current class, then
311 // the target class k. Resolution exceptions will be passed on by upper
312 // layers. IncompatibleClassChangeErrors from membership validation failures
313 // will also be passed through.
314
315 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
316 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
317 if (cur_host == NULL) {
318 return false;
319 }
320
321 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
322 if (k_nest_host == NULL) {
323 return false;
324 }
325
326 bool access = (cur_host == k_nest_host);
327
328 if (log_is_enabled(Trace, class, nestmates)) {
329 ResourceMark rm(THREAD);
330 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
331 this->external_name(),
332 access ? "" : "NOT ",
333 k->external_name());
334 }
335
336 return access;
337 }
338
339 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
340 const int size = InstanceKlass::size(parser.vtable_size(),
341 parser.itable_size(),
342 nonstatic_oop_map_size(parser.total_oop_map_count()),
343 parser.is_interface(),
344 parser.is_anonymous(),
345 should_store_fingerprint(parser.is_anonymous()));
346
347 const Symbol* const class_name = parser.class_name();
348 assert(class_name != NULL, "invariant");
349 ClassLoaderData* loader_data = parser.loader_data();
350 assert(loader_data != NULL, "invariant");
351
352 InstanceKlass* ik;
353
354 // Allocation
355 if (REF_NONE == parser.reference_type()) {
356 if (class_name == vmSymbols::java_lang_Class()) {
357 // mirror
358 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
359 }
360 else if (is_class_loader(class_name, parser)) {
361 // class loader
362 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
363 } else {
364 // normal
365 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
366 }
367 } else {
368 // reference
369 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
370 }
371
372 // Check for pending exception before adding to the loader data and incrementing
373 // class count. Can get OOM here.
374 if (HAS_PENDING_EXCEPTION) {
375 return NULL;
376 }
377
378 return ik;
379 }
380
381
382 // copy method ordering from resource area to Metaspace
383 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
384 if (m != NULL) {
385 // allocate a new array and copy contents (memcpy?)
386 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
387 for (int i = 0; i < m->length(); i++) {
388 _method_ordering->at_put(i, m->at(i));
389 }
390 } else {
391 _method_ordering = Universe::the_empty_int_array();
392 }
393 }
394
395 // create a new array of vtable_indices for default methods
396 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
397 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
398 assert(default_vtable_indices() == NULL, "only create once");
399 set_default_vtable_indices(vtable_indices);
400 return vtable_indices;
401 }
402
403 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
404 Klass(id),
405 _static_field_size(parser.static_field_size()),
406 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
407 _itable_len(parser.itable_size()),
408 _reference_type(parser.reference_type()),
409 _nest_members(NULL),
410 _nest_host_index(0),
411 _nest_host(NULL) {
412 set_vtable_length(parser.vtable_size());
413 set_kind(kind);
414 set_access_flags(parser.access_flags());
415 set_is_anonymous(parser.is_anonymous());
416 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
417 false));
418
419 assert(NULL == _methods, "underlying memory not zeroed?");
420 assert(is_instance_klass(), "is layout incorrect?");
421 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
422 }
423
424 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
425 Array<Method*>* methods) {
426 if (methods != NULL && methods != Universe::the_empty_method_array() &&
427 !methods->is_shared()) {
428 for (int i = 0; i < methods->length(); i++) {
429 Method* method = methods->at(i);
430 if (method == NULL) continue; // maybe null if error processing
431 // Only want to delete methods that are not executing for RedefineClasses.
432 // The previous version will point to them so they're not totally dangling
433 assert (!method->on_stack(), "shouldn't be called with methods on stack");
434 MetadataFactory::free_metadata(loader_data, method);
435 }
436 MetadataFactory::free_array<Method*>(loader_data, methods);
437 }
438 }
439
440 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
441 const Klass* super_klass,
442 Array<Klass*>* local_interfaces,
443 Array<Klass*>* transitive_interfaces) {
444 // Only deallocate transitive interfaces if not empty, same as super class
445 // or same as local interfaces. See code in parseClassFile.
446 Array<Klass*>* ti = transitive_interfaces;
447 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
448 // check that the interfaces don't come from super class
449 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
450 InstanceKlass::cast(super_klass)->transitive_interfaces();
451 if (ti != sti && ti != NULL && !ti->is_shared()) {
452 MetadataFactory::free_array<Klass*>(loader_data, ti);
453 }
454 }
455
456 // local interfaces can be empty
457 if (local_interfaces != Universe::the_empty_klass_array() &&
458 local_interfaces != NULL && !local_interfaces->is_shared()) {
459 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
460 }
461 }
462
463 // This function deallocates the metadata and C heap pointers that the
464 // InstanceKlass points to.
465 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
466
467 // Orphan the mirror first, CMS thinks it's still live.
468 if (java_mirror() != NULL) {
469 java_lang_Class::set_klass(java_mirror(), NULL);
470 }
471
472 // Also remove mirror from handles
473 loader_data->remove_handle(_java_mirror);
474
475 // Need to take this class off the class loader data list.
476 loader_data->remove_class(this);
477
478 // The array_klass for this class is created later, after error handling.
479 // For class redefinition, we keep the original class so this scratch class
480 // doesn't have an array class. Either way, assert that there is nothing
481 // to deallocate.
482 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
483
484 // Release C heap allocated data that this might point to, which includes
485 // reference counting symbol names.
486 release_C_heap_structures();
487
488 deallocate_methods(loader_data, methods());
489 set_methods(NULL);
490
491 if (method_ordering() != NULL &&
492 method_ordering() != Universe::the_empty_int_array() &&
493 !method_ordering()->is_shared()) {
494 MetadataFactory::free_array<int>(loader_data, method_ordering());
495 }
496 set_method_ordering(NULL);
497
498 // default methods can be empty
499 if (default_methods() != NULL &&
500 default_methods() != Universe::the_empty_method_array() &&
501 !default_methods()->is_shared()) {
502 MetadataFactory::free_array<Method*>(loader_data, default_methods());
503 }
504 // Do NOT deallocate the default methods, they are owned by superinterfaces.
505 set_default_methods(NULL);
506
507 // default methods vtable indices can be empty
508 if (default_vtable_indices() != NULL &&
509 !default_vtable_indices()->is_shared()) {
510 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
511 }
512 set_default_vtable_indices(NULL);
513
514
515 // This array is in Klass, but remove it with the InstanceKlass since
516 // this place would be the only caller and it can share memory with transitive
517 // interfaces.
518 if (secondary_supers() != NULL &&
519 secondary_supers() != Universe::the_empty_klass_array() &&
520 secondary_supers() != transitive_interfaces() &&
521 !secondary_supers()->is_shared()) {
522 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
523 }
524 set_secondary_supers(NULL);
525
526 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
527 set_transitive_interfaces(NULL);
528 set_local_interfaces(NULL);
529
530 if (fields() != NULL && !fields()->is_shared()) {
531 MetadataFactory::free_array<jushort>(loader_data, fields());
532 }
533 set_fields(NULL, 0);
534
535 // If a method from a redefined class is using this constant pool, don't
536 // delete it, yet. The new class's previous version will point to this.
537 if (constants() != NULL) {
538 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
539 if (!constants()->is_shared()) {
540 MetadataFactory::free_metadata(loader_data, constants());
541 }
542 // Delete any cached resolution errors for the constant pool
543 SystemDictionary::delete_resolution_error(constants());
544
545 set_constants(NULL);
546 }
547
548 if (inner_classes() != NULL &&
549 inner_classes() != Universe::the_empty_short_array() &&
550 !inner_classes()->is_shared()) {
551 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
552 }
553 set_inner_classes(NULL);
554
555 if (nest_members() != NULL &&
556 nest_members() != Universe::the_empty_short_array() &&
557 !nest_members()->is_shared()) {
558 MetadataFactory::free_array<jushort>(loader_data, nest_members());
559 }
560 set_nest_members(NULL);
561
562 // We should deallocate the Annotations instance if it's not in shared spaces.
563 if (annotations() != NULL && !annotations()->is_shared()) {
564 MetadataFactory::free_metadata(loader_data, annotations());
565 }
566 set_annotations(NULL);
567 }
568
569 bool InstanceKlass::should_be_initialized() const {
570 return !is_initialized();
571 }
572
573 klassItable InstanceKlass::itable() const {
574 return klassItable(const_cast<InstanceKlass*>(this));
575 }
576
577 void InstanceKlass::eager_initialize(Thread *thread) {
578 if (!EagerInitialization) return;
579
580 if (this->is_not_initialized()) {
581 // abort if the the class has a class initializer
582 if (this->class_initializer() != NULL) return;
583
584 // abort if it is java.lang.Object (initialization is handled in genesis)
585 Klass* super_klass = super();
586 if (super_klass == NULL) return;
587
588 // abort if the super class should be initialized
589 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
590
591 // call body to expose the this pointer
592 eager_initialize_impl();
593 }
594 }
595
596 // JVMTI spec thinks there are signers and protection domain in the
597 // instanceKlass. These accessors pretend these fields are there.
598 // The hprof specification also thinks these fields are in InstanceKlass.
599 oop InstanceKlass::protection_domain() const {
600 // return the protection_domain from the mirror
601 return java_lang_Class::protection_domain(java_mirror());
602 }
603
604 // To remove these from requires an incompatible change and CCC request.
605 objArrayOop InstanceKlass::signers() const {
606 // return the signers from the mirror
607 return java_lang_Class::signers(java_mirror());
608 }
609
610 oop InstanceKlass::init_lock() const {
611 // return the init lock from the mirror
612 oop lock = java_lang_Class::init_lock(java_mirror());
613 // Prevent reordering with any access of initialization state
614 OrderAccess::loadload();
615 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
616 "only fully initialized state can have a null lock");
617 return lock;
618 }
619
620 // Set the initialization lock to null so the object can be GC'ed. Any racing
621 // threads to get this lock will see a null lock and will not lock.
622 // That's okay because they all check for initialized state after getting
623 // the lock and return.
624 void InstanceKlass::fence_and_clear_init_lock() {
625 // make sure previous stores are all done, notably the init_state.
626 OrderAccess::storestore();
627 java_lang_Class::set_init_lock(java_mirror(), NULL);
628 assert(!is_not_initialized(), "class must be initialized now");
629 }
630
631 void InstanceKlass::eager_initialize_impl() {
632 EXCEPTION_MARK;
633 HandleMark hm(THREAD);
634 Handle h_init_lock(THREAD, init_lock());
635 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
636
637 // abort if someone beat us to the initialization
638 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
639
640 ClassState old_state = init_state();
641 link_class_impl(true, THREAD);
642 if (HAS_PENDING_EXCEPTION) {
643 CLEAR_PENDING_EXCEPTION;
644 // Abort if linking the class throws an exception.
645
646 // Use a test to avoid redundantly resetting the state if there's
647 // no change. Set_init_state() asserts that state changes make
648 // progress, whereas here we might just be spinning in place.
649 if (old_state != _init_state)
650 set_init_state(old_state);
651 } else {
652 // linking successfull, mark class as initialized
653 set_init_state(fully_initialized);
654 fence_and_clear_init_lock();
655 // trace
656 if (log_is_enabled(Info, class, init)) {
657 ResourceMark rm(THREAD);
658 log_info(class, init)("[Initialized %s without side effects]", external_name());
659 }
660 }
661 }
662
663
664 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
665 // process. The step comments refers to the procedure described in that section.
666 // Note: implementation moved to static method to expose the this pointer.
667 void InstanceKlass::initialize(TRAPS) {
668 if (this->should_be_initialized()) {
669 initialize_impl(CHECK);
670 // Note: at this point the class may be initialized
671 // OR it may be in the state of being initialized
672 // in case of recursive initialization!
673 } else {
674 assert(is_initialized(), "sanity check");
675 }
676 }
677
678
679 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
680 // 1) Verify the bytecodes
681 Verifier::Mode mode =
682 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
683 return Verifier::verify(this, mode, should_verify_class(), THREAD);
684 }
685
686
687 // Used exclusively by the shared spaces dump mechanism to prevent
688 // classes mapped into the shared regions in new VMs from appearing linked.
689
690 void InstanceKlass::unlink_class() {
691 assert(is_linked(), "must be linked");
692 _init_state = loaded;
693 }
694
695 void InstanceKlass::link_class(TRAPS) {
696 assert(is_loaded(), "must be loaded");
697 if (!is_linked()) {
698 link_class_impl(true, CHECK);
699 }
700 }
701
702 // Called to verify that a class can link during initialization, without
703 // throwing a VerifyError.
704 bool InstanceKlass::link_class_or_fail(TRAPS) {
705 assert(is_loaded(), "must be loaded");
706 if (!is_linked()) {
707 link_class_impl(false, CHECK_false);
708 }
709 return is_linked();
710 }
711
712 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
713 if (DumpSharedSpaces && is_in_error_state()) {
714 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
715 // the class has failed verification. Throwing the NoClassDefFoundError here is just
716 // a convenient way to stop repeat attempts to verify the same (bad) class.
717 //
718 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
719 // if we are executing Java code. This is not a problem for CDS dumping phase since
720 // it doesn't execute any Java code.
721 ResourceMark rm(THREAD);
722 Exceptions::fthrow(THREAD_AND_LOCATION,
723 vmSymbols::java_lang_NoClassDefFoundError(),
724 "Class %s, or one of its supertypes, failed class initialization",
725 external_name());
726 return false;
727 }
728 // return if already verified
729 if (is_linked()) {
730 return true;
731 }
732
733 // Timing
734 // timer handles recursion
735 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
736 JavaThread* jt = (JavaThread*)THREAD;
737
738 // link super class before linking this class
739 Klass* super_klass = super();
740 if (super_klass != NULL) {
741 if (super_klass->is_interface()) { // check if super class is an interface
742 ResourceMark rm(THREAD);
743 Exceptions::fthrow(
744 THREAD_AND_LOCATION,
745 vmSymbols::java_lang_IncompatibleClassChangeError(),
746 "class %s has interface %s as super class",
747 external_name(),
748 super_klass->external_name()
749 );
750 return false;
751 }
752
753 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
754 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
755 }
756
757 // link all interfaces implemented by this class before linking this class
758 Array<Klass*>* interfaces = local_interfaces();
759 int num_interfaces = interfaces->length();
760 for (int index = 0; index < num_interfaces; index++) {
761 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
762 interk->link_class_impl(throw_verifyerror, CHECK_false);
763 }
764
765 // in case the class is linked in the process of linking its superclasses
766 if (is_linked()) {
767 return true;
768 }
769
770 // trace only the link time for this klass that includes
771 // the verification time
772 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
773 ClassLoader::perf_class_link_selftime(),
774 ClassLoader::perf_classes_linked(),
775 jt->get_thread_stat()->perf_recursion_counts_addr(),
776 jt->get_thread_stat()->perf_timers_addr(),
777 PerfClassTraceTime::CLASS_LINK);
778
779 // verification & rewriting
780 {
781 HandleMark hm(THREAD);
782 Handle h_init_lock(THREAD, init_lock());
783 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
784 // rewritten will have been set if loader constraint error found
785 // on an earlier link attempt
786 // don't verify or rewrite if already rewritten
787 //
788
789 if (!is_linked()) {
790 if (!is_rewritten()) {
791 {
792 bool verify_ok = verify_code(throw_verifyerror, THREAD);
793 if (!verify_ok) {
794 return false;
795 }
796 }
797
798 // Just in case a side-effect of verify linked this class already
799 // (which can sometimes happen since the verifier loads classes
800 // using custom class loaders, which are free to initialize things)
801 if (is_linked()) {
802 return true;
803 }
804
805 // also sets rewritten
806 rewrite_class(CHECK_false);
807 } else if (is_shared()) {
808 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
809 }
810
811 // relocate jsrs and link methods after they are all rewritten
812 link_methods(CHECK_false);
813
814 // Initialize the vtable and interface table after
815 // methods have been rewritten since rewrite may
816 // fabricate new Method*s.
817 // also does loader constraint checking
818 //
819 // initialize_vtable and initialize_itable need to be rerun for
820 // a shared class if the class is not loaded by the NULL classloader.
821 ClassLoaderData * loader_data = class_loader_data();
822 if (!(is_shared() &&
823 loader_data->is_the_null_class_loader_data())) {
824 ResourceMark rm(THREAD);
825 vtable().initialize_vtable(true, CHECK_false);
826 itable().initialize_itable(true, CHECK_false);
827 }
828 #ifdef ASSERT
829 else {
830 vtable().verify(tty, true);
831 // In case itable verification is ever added.
832 // itable().verify(tty, true);
833 }
834 #endif
835 set_init_state(linked);
836 if (JvmtiExport::should_post_class_prepare()) {
837 Thread *thread = THREAD;
838 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
839 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
840 }
841 }
842 }
843 return true;
844 }
845
846 // Rewrite the byte codes of all of the methods of a class.
847 // The rewriter must be called exactly once. Rewriting must happen after
848 // verification but before the first method of the class is executed.
849 void InstanceKlass::rewrite_class(TRAPS) {
850 assert(is_loaded(), "must be loaded");
851 if (is_rewritten()) {
852 assert(is_shared(), "rewriting an unshared class?");
853 return;
854 }
855 Rewriter::rewrite(this, CHECK);
856 set_rewritten();
857 }
858
859 // Now relocate and link method entry points after class is rewritten.
860 // This is outside is_rewritten flag. In case of an exception, it can be
861 // executed more than once.
862 void InstanceKlass::link_methods(TRAPS) {
863 int len = methods()->length();
864 for (int i = len-1; i >= 0; i--) {
865 methodHandle m(THREAD, methods()->at(i));
866
867 // Set up method entry points for compiler and interpreter .
868 m->link_method(m, CHECK);
869 }
870 }
871
872 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
873 void InstanceKlass::initialize_super_interfaces(TRAPS) {
874 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
875 for (int i = 0; i < local_interfaces()->length(); ++i) {
876 Klass* iface = local_interfaces()->at(i);
877 InstanceKlass* ik = InstanceKlass::cast(iface);
878
879 // Initialization is depth first search ie. we start with top of the inheritance tree
880 // has_nonstatic_concrete_methods drives searching superinterfaces since it
881 // means has_nonstatic_concrete_methods in its superinterface hierarchy
882 if (ik->has_nonstatic_concrete_methods()) {
883 ik->initialize_super_interfaces(CHECK);
884 }
885
886 // Only initialize() interfaces that "declare" concrete methods.
887 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
888 ik->initialize(CHECK);
889 }
890 }
891 }
892
893 void InstanceKlass::initialize_impl(TRAPS) {
894 HandleMark hm(THREAD);
895
896 // Make sure klass is linked (verified) before initialization
897 // A class could already be verified, since it has been reflected upon.
898 link_class(CHECK);
899
900 DTRACE_CLASSINIT_PROBE(required, -1);
901
902 bool wait = false;
903
904 // refer to the JVM book page 47 for description of steps
905 // Step 1
906 {
907 Handle h_init_lock(THREAD, init_lock());
908 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
909
910 Thread *self = THREAD; // it's passed the current thread
911
912 // Step 2
913 // If we were to use wait() instead of waitInterruptibly() then
914 // we might end up throwing IE from link/symbol resolution sites
915 // that aren't expected to throw. This would wreak havoc. See 6320309.
916 while(is_being_initialized() && !is_reentrant_initialization(self)) {
917 wait = true;
918 ol.waitUninterruptibly(CHECK);
919 }
920
921 // Step 3
922 if (is_being_initialized() && is_reentrant_initialization(self)) {
923 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
924 return;
925 }
926
927 // Step 4
928 if (is_initialized()) {
929 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
930 return;
931 }
932
933 // Step 5
934 if (is_in_error_state()) {
935 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
936 ResourceMark rm(THREAD);
937 // Delegate throwing of NoClassDefFoundError to java handler
938 class_loader_data()->throw_reinit_exception(java_mirror_handle(), THREAD);
939 if (HAS_PENDING_EXCEPTION) {
940 Handle e(THREAD, PENDING_EXCEPTION);
941 CLEAR_PENDING_EXCEPTION;
942 if (e->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
943 // java handler has thrown correct type of exception -> rethrow it
944 THROW_OOP(e());
945 }
946 }
947 // misbehaving/incapable java handler (throwing OOME or not at all) -> fallback
948 const char* className = external_name();
949 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
950 }
951
952 // Step 6
953 set_init_state(being_initialized);
954 set_init_thread(self);
955 }
956
957 // Step 7
958 // Next, if C is a class rather than an interface, initialize it's super class and super
959 // interfaces.
960 if (!is_interface()) {
961 Klass* super_klass = super();
962 if (super_klass != NULL && super_klass->should_be_initialized()) {
963 super_klass->initialize(THREAD);
964 }
965 // If C implements any interface that declares a non-static, concrete method,
966 // the initialization of C triggers initialization of its super interfaces.
967 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
968 // having a superinterface that declares, non-static, concrete methods
969 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
970 initialize_super_interfaces(THREAD);
971 }
972
973 // If any exceptions, complete abruptly, throwing the same exception as above.
974 if (HAS_PENDING_EXCEPTION) {
975 Handle e(THREAD, PENDING_EXCEPTION);
976 CLEAR_PENDING_EXCEPTION;
977 {
978 EXCEPTION_MARK;
979 // Record the exception thrown from super class/interface initialization so that
980 // it can be chained into potential later NoClassDefFoundErrors.
981 class_loader_data()->record_init_exception(java_mirror_handle(), e, THREAD);
982 // Locks object, set state, and notify all waiting threads
983 set_initialization_state_and_notify(initialization_error, THREAD);
984 CLEAR_PENDING_EXCEPTION;
985 }
986 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
987 THROW_OOP(e());
988 }
989 }
990
991
992 // Look for aot compiled methods for this klass, including class initializer.
993 AOTLoader::load_for_klass(this, THREAD);
994
995 // Step 8
996 {
997 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
998 JavaThread* jt = (JavaThread*)THREAD;
999 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1000 // Timer includes any side effects of class initialization (resolution,
1001 // etc), but not recursive entry into call_class_initializer().
1002 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1003 ClassLoader::perf_class_init_selftime(),
1004 ClassLoader::perf_classes_inited(),
1005 jt->get_thread_stat()->perf_recursion_counts_addr(),
1006 jt->get_thread_stat()->perf_timers_addr(),
1007 PerfClassTraceTime::CLASS_CLINIT);
1008 call_class_initializer(THREAD);
1009 }
1010
1011 // Step 9
1012 if (!HAS_PENDING_EXCEPTION) {
1013 set_initialization_state_and_notify(fully_initialized, CHECK);
1014 {
1015 debug_only(vtable().verify(tty, true);)
1016 }
1017 }
1018 else {
1019 // Step 10 and 11
1020 Handle e(THREAD, PENDING_EXCEPTION);
1021 CLEAR_PENDING_EXCEPTION;
1022 // JVMTI has already reported the pending exception
1023 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1024 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1025 {
1026 EXCEPTION_MARK;
1027 if (!e->is_a(SystemDictionary::Error_klass())) {
1028 // Wrap anything but errors into ExceptionInInitializerError.
1029 JavaCallArguments args(e);
1030 Handle h_loader(THREAD, NULL);
1031 Handle h_prot(THREAD, NULL);
1032 e = Exceptions::new_exception(THREAD,
1033 vmSymbols::java_lang_ExceptionInInitializerError(),
1034 vmSymbols::throwable_void_signature(),
1035 &args, h_loader, h_prot);
1036 }
1037 // Record the exception that originally caused <clinit> to fail so
1038 // it can be chained into potential later NoClassDefFoundErrors.
1039 class_loader_data()->record_init_exception(java_mirror_handle(), e, THREAD);
1040 // Locks object, set state, and notify all waiting threads
1041 set_initialization_state_and_notify(initialization_error, THREAD);
1042 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1043 // JVMTI has already reported the pending exception
1044 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1045 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1046 }
1047 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1048 THROW_OOP(e());
1049 }
1050 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1051 }
1052
1053
1054 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1055 Handle h_init_lock(THREAD, init_lock());
1056 if (h_init_lock() != NULL) {
1057 ObjectLocker ol(h_init_lock, THREAD);
1058 set_init_state(state);
1059 fence_and_clear_init_lock();
1060 ol.notify_all(CHECK);
1061 } else {
1062 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1063 set_init_state(state);
1064 }
1065 }
1066
1067 // The embedded _implementor field can only record one implementor.
1068 // When there are more than one implementors, the _implementor field
1069 // is set to the interface Klass* itself. Following are the possible
1070 // values for the _implementor field:
1071 // NULL - no implementor
1072 // implementor Klass* - one implementor
1073 // self - more than one implementor
1074 //
1075 // The _implementor field only exists for interfaces.
1076 void InstanceKlass::add_implementor(Klass* k) {
1077 assert(Compile_lock->owned_by_self(), "");
1078 assert(is_interface(), "not interface");
1079 // Filter out my subinterfaces.
1080 // (Note: Interfaces are never on the subklass list.)
1081 if (InstanceKlass::cast(k)->is_interface()) return;
1082
1083 // Filter out subclasses whose supers already implement me.
1084 // (Note: CHA must walk subclasses of direct implementors
1085 // in order to locate indirect implementors.)
1086 Klass* sk = k->super();
1087 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1088 // We only need to check one immediate superclass, since the
1089 // implements_interface query looks at transitive_interfaces.
1090 // Any supers of the super have the same (or fewer) transitive_interfaces.
1091 return;
1092
1093 Klass* ik = implementor();
1094 if (ik == NULL) {
1095 set_implementor(k);
1096 } else if (ik != this) {
1097 // There is already an implementor. Use itself as an indicator of
1098 // more than one implementors.
1099 set_implementor(this);
1100 }
1101
1102 // The implementor also implements the transitive_interfaces
1103 for (int index = 0; index < local_interfaces()->length(); index++) {
1104 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1105 }
1106 }
1107
1108 void InstanceKlass::init_implementor() {
1109 if (is_interface()) {
1110 set_implementor(NULL);
1111 }
1112 }
1113
1114
1115 void InstanceKlass::process_interfaces(Thread *thread) {
1116 // link this class into the implementors list of every interface it implements
1117 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1118 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1119 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1120 assert(interf->is_interface(), "expected interface");
1121 interf->add_implementor(this);
1122 }
1123 }
1124
1125 bool InstanceKlass::can_be_primary_super_slow() const {
1126 if (is_interface())
1127 return false;
1128 else
1129 return Klass::can_be_primary_super_slow();
1130 }
1131
1132 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1133 Array<Klass*>* transitive_interfaces) {
1134 // The secondaries are the implemented interfaces.
1135 Array<Klass*>* interfaces = transitive_interfaces;
1136 int num_secondaries = num_extra_slots + interfaces->length();
1137 if (num_secondaries == 0) {
1138 // Must share this for correct bootstrapping!
1139 set_secondary_supers(Universe::the_empty_klass_array());
1140 return NULL;
1141 } else if (num_extra_slots == 0) {
1142 // The secondary super list is exactly the same as the transitive interfaces.
1143 // Redefine classes has to be careful not to delete this!
1144 set_secondary_supers(interfaces);
1145 return NULL;
1146 } else {
1147 // Copy transitive interfaces to a temporary growable array to be constructed
1148 // into the secondary super list with extra slots.
1149 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1150 for (int i = 0; i < interfaces->length(); i++) {
1151 secondaries->push(interfaces->at(i));
1152 }
1153 return secondaries;
1154 }
1155 }
1156
1157 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1158 if (k->is_interface()) {
1159 return implements_interface(k);
1160 } else {
1161 return Klass::compute_is_subtype_of(k);
1162 }
1163 }
1164
1165 bool InstanceKlass::implements_interface(Klass* k) const {
1166 if (this == k) return true;
1167 assert(k->is_interface(), "should be an interface class");
1168 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1169 if (transitive_interfaces()->at(i) == k) {
1170 return true;
1171 }
1172 }
1173 return false;
1174 }
1175
1176 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1177 // Verify direct super interface
1178 if (this == k) return true;
1179 assert(k->is_interface(), "should be an interface class");
1180 for (int i = 0; i < local_interfaces()->length(); i++) {
1181 if (local_interfaces()->at(i) == k) {
1182 return true;
1183 }
1184 }
1185 return false;
1186 }
1187
1188 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1189 if (length < 0) {
1190 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1191 }
1192 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1193 report_java_out_of_memory("Requested array size exceeds VM limit");
1194 JvmtiExport::post_array_size_exhausted();
1195 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1196 }
1197 int size = objArrayOopDesc::object_size(length);
1198 Klass* ak = array_klass(n, CHECK_NULL);
1199 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1200 /* do_zero */ true, CHECK_NULL);
1201 return o;
1202 }
1203
1204 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1205 if (TraceFinalizerRegistration) {
1206 tty->print("Registered ");
1207 i->print_value_on(tty);
1208 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1209 }
1210 instanceHandle h_i(THREAD, i);
1211 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1212 JavaValue result(T_VOID);
1213 JavaCallArguments args(h_i);
1214 methodHandle mh (THREAD, Universe::finalizer_register_method());
1215 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1216 return h_i();
1217 }
1218
1219 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1220 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1221 int size = size_helper(); // Query before forming handle.
1222
1223 instanceOop i;
1224
1225 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1226 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1227 i = register_finalizer(i, CHECK_NULL);
1228 }
1229 return i;
1230 }
1231
1232 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1233 return instanceHandle(THREAD, allocate_instance(THREAD));
1234 }
1235
1236 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1237 if (is_interface() || is_abstract()) {
1238 ResourceMark rm(THREAD);
1239 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1240 : vmSymbols::java_lang_InstantiationException(), external_name());
1241 }
1242 if (this == SystemDictionary::Class_klass()) {
1243 ResourceMark rm(THREAD);
1244 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1245 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1246 }
1247 }
1248
1249 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1250 // Need load-acquire for lock-free read
1251 if (array_klasses_acquire() == NULL) {
1252 if (or_null) return NULL;
1253
1254 ResourceMark rm;
1255 JavaThread *jt = (JavaThread *)THREAD;
1256 {
1257 // Atomic creation of array_klasses
1258 MutexLocker mc(Compile_lock, THREAD); // for vtables
1259 MutexLocker ma(MultiArray_lock, THREAD);
1260
1261 // Check if update has already taken place
1262 if (array_klasses() == NULL) {
1263 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1264 // use 'release' to pair with lock-free load
1265 release_set_array_klasses(k);
1266 }
1267 }
1268 }
1269 // _this will always be set at this point
1270 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1271 if (or_null) {
1272 return oak->array_klass_or_null(n);
1273 }
1274 return oak->array_klass(n, THREAD);
1275 }
1276
1277 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1278 return array_klass_impl(or_null, 1, THREAD);
1279 }
1280
1281 static int call_class_initializer_counter = 0; // for debugging
1282
1283 Method* InstanceKlass::class_initializer() const {
1284 Method* clinit = find_method(
1285 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1286 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1287 return clinit;
1288 }
1289 return NULL;
1290 }
1291
1292 void InstanceKlass::call_class_initializer(TRAPS) {
1293 if (ReplayCompiles &&
1294 (ReplaySuppressInitializers == 1 ||
1295 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1296 // Hide the existence of the initializer for the purpose of replaying the compile
1297 return;
1298 }
1299
1300 methodHandle h_method(THREAD, class_initializer());
1301 assert(!is_initialized(), "we cannot initialize twice");
1302 LogTarget(Info, class, init) lt;
1303 if (lt.is_enabled()) {
1304 ResourceMark rm;
1305 LogStream ls(lt);
1306 ls.print("%d Initializing ", call_class_initializer_counter++);
1307 name()->print_value_on(&ls);
1308 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1309 }
1310 if (h_method() != NULL) {
1311 JavaCallArguments args; // No arguments
1312 JavaValue result(T_VOID);
1313 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1314 }
1315 }
1316
1317
1318 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1319 InterpreterOopMap* entry_for) {
1320 // Lazily create the _oop_map_cache at first request
1321 // Lock-free access requires load_acquire.
1322 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1323 if (oop_map_cache == NULL) {
1324 MutexLocker x(OopMapCacheAlloc_lock);
1325 // Check if _oop_map_cache was allocated while we were waiting for this lock
1326 if ((oop_map_cache = _oop_map_cache) == NULL) {
1327 oop_map_cache = new OopMapCache();
1328 // Ensure _oop_map_cache is stable, since it is examined without a lock
1329 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1330 }
1331 }
1332 // _oop_map_cache is constant after init; lookup below does its own locking.
1333 oop_map_cache->lookup(method, bci, entry_for);
1334 }
1335
1336
1337 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1338 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1339 Symbol* f_name = fs.name();
1340 Symbol* f_sig = fs.signature();
1341 if (f_name == name && f_sig == sig) {
1342 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1343 return true;
1344 }
1345 }
1346 return false;
1347 }
1348
1349
1350 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1351 const int n = local_interfaces()->length();
1352 for (int i = 0; i < n; i++) {
1353 Klass* intf1 = local_interfaces()->at(i);
1354 assert(intf1->is_interface(), "just checking type");
1355 // search for field in current interface
1356 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1357 assert(fd->is_static(), "interface field must be static");
1358 return intf1;
1359 }
1360 // search for field in direct superinterfaces
1361 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1362 if (intf2 != NULL) return intf2;
1363 }
1364 // otherwise field lookup fails
1365 return NULL;
1366 }
1367
1368
1369 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1370 // search order according to newest JVM spec (5.4.3.2, p.167).
1371 // 1) search for field in current klass
1372 if (find_local_field(name, sig, fd)) {
1373 return const_cast<InstanceKlass*>(this);
1374 }
1375 // 2) search for field recursively in direct superinterfaces
1376 { Klass* intf = find_interface_field(name, sig, fd);
1377 if (intf != NULL) return intf;
1378 }
1379 // 3) apply field lookup recursively if superclass exists
1380 { Klass* supr = super();
1381 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1382 }
1383 // 4) otherwise field lookup fails
1384 return NULL;
1385 }
1386
1387
1388 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1389 // search order according to newest JVM spec (5.4.3.2, p.167).
1390 // 1) search for field in current klass
1391 if (find_local_field(name, sig, fd)) {
1392 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1393 }
1394 // 2) search for field recursively in direct superinterfaces
1395 if (is_static) {
1396 Klass* intf = find_interface_field(name, sig, fd);
1397 if (intf != NULL) return intf;
1398 }
1399 // 3) apply field lookup recursively if superclass exists
1400 { Klass* supr = super();
1401 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1402 }
1403 // 4) otherwise field lookup fails
1404 return NULL;
1405 }
1406
1407
1408 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1409 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1410 if (fs.offset() == offset) {
1411 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1412 if (fd->is_static() == is_static) return true;
1413 }
1414 }
1415 return false;
1416 }
1417
1418
1419 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1420 Klass* klass = const_cast<InstanceKlass*>(this);
1421 while (klass != NULL) {
1422 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1423 return true;
1424 }
1425 klass = klass->super();
1426 }
1427 return false;
1428 }
1429
1430
1431 void InstanceKlass::methods_do(void f(Method* method)) {
1432 // Methods aren't stable until they are loaded. This can be read outside
1433 // a lock through the ClassLoaderData for profiling
1434 if (!is_loaded()) {
1435 return;
1436 }
1437
1438 int len = methods()->length();
1439 for (int index = 0; index < len; index++) {
1440 Method* m = methods()->at(index);
1441 assert(m->is_method(), "must be method");
1442 f(m);
1443 }
1444 }
1445
1446
1447 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1448 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1449 if (fs.access_flags().is_static()) {
1450 fieldDescriptor& fd = fs.field_descriptor();
1451 cl->do_field(&fd);
1452 }
1453 }
1454 }
1455
1456
1457 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1458 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1459 if (fs.access_flags().is_static()) {
1460 fieldDescriptor& fd = fs.field_descriptor();
1461 f(&fd, mirror, CHECK);
1462 }
1463 }
1464 }
1465
1466
1467 static int compare_fields_by_offset(int* a, int* b) {
1468 return a[0] - b[0];
1469 }
1470
1471 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1472 InstanceKlass* super = superklass();
1473 if (super != NULL) {
1474 super->do_nonstatic_fields(cl);
1475 }
1476 fieldDescriptor fd;
1477 int length = java_fields_count();
1478 // In DebugInfo nonstatic fields are sorted by offset.
1479 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1480 int j = 0;
1481 for (int i = 0; i < length; i += 1) {
1482 fd.reinitialize(this, i);
1483 if (!fd.is_static()) {
1484 fields_sorted[j + 0] = fd.offset();
1485 fields_sorted[j + 1] = i;
1486 j += 2;
1487 }
1488 }
1489 if (j > 0) {
1490 length = j;
1491 // _sort_Fn is defined in growableArray.hpp.
1492 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1493 for (int i = 0; i < length; i += 2) {
1494 fd.reinitialize(this, fields_sorted[i + 1]);
1495 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1496 cl->do_field(&fd);
1497 }
1498 }
1499 FREE_C_HEAP_ARRAY(int, fields_sorted);
1500 }
1501
1502
1503 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1504 if (array_klasses() != NULL)
1505 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1506 }
1507
1508 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1509 if (array_klasses() != NULL)
1510 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1511 }
1512
1513 #ifdef ASSERT
1514 static int linear_search(const Array<Method*>* methods,
1515 const Symbol* name,
1516 const Symbol* signature) {
1517 const int len = methods->length();
1518 for (int index = 0; index < len; index++) {
1519 const Method* const m = methods->at(index);
1520 assert(m->is_method(), "must be method");
1521 if (m->signature() == signature && m->name() == name) {
1522 return index;
1523 }
1524 }
1525 return -1;
1526 }
1527 #endif
1528
1529 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1530 int len = methods->length();
1531 // methods are sorted, so do binary search
1532 int l = 0;
1533 int h = len - 1;
1534 while (l <= h) {
1535 int mid = (l + h) >> 1;
1536 Method* m = methods->at(mid);
1537 assert(m->is_method(), "must be method");
1538 int res = m->name()->fast_compare(name);
1539 if (res == 0) {
1540 return mid;
1541 } else if (res < 0) {
1542 l = mid + 1;
1543 } else {
1544 h = mid - 1;
1545 }
1546 }
1547 return -1;
1548 }
1549
1550 // find_method looks up the name/signature in the local methods array
1551 Method* InstanceKlass::find_method(const Symbol* name,
1552 const Symbol* signature) const {
1553 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1554 }
1555
1556 Method* InstanceKlass::find_method_impl(const Symbol* name,
1557 const Symbol* signature,
1558 OverpassLookupMode overpass_mode,
1559 StaticLookupMode static_mode,
1560 PrivateLookupMode private_mode) const {
1561 return InstanceKlass::find_method_impl(methods(),
1562 name,
1563 signature,
1564 overpass_mode,
1565 static_mode,
1566 private_mode);
1567 }
1568
1569 // find_instance_method looks up the name/signature in the local methods array
1570 // and skips over static methods
1571 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1572 const Symbol* name,
1573 const Symbol* signature,
1574 PrivateLookupMode private_mode) {
1575 Method* const meth = InstanceKlass::find_method_impl(methods,
1576 name,
1577 signature,
1578 find_overpass,
1579 skip_static,
1580 private_mode);
1581 assert(((meth == NULL) || !meth->is_static()),
1582 "find_instance_method should have skipped statics");
1583 return meth;
1584 }
1585
1586 // find_instance_method looks up the name/signature in the local methods array
1587 // and skips over static methods
1588 Method* InstanceKlass::find_instance_method(const Symbol* name,
1589 const Symbol* signature,
1590 PrivateLookupMode private_mode) const {
1591 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1592 }
1593
1594 // Find looks up the name/signature in the local methods array
1595 // and filters on the overpass, static and private flags
1596 // This returns the first one found
1597 // note that the local methods array can have up to one overpass, one static
1598 // and one instance (private or not) with the same name/signature
1599 Method* InstanceKlass::find_local_method(const Symbol* name,
1600 const Symbol* signature,
1601 OverpassLookupMode overpass_mode,
1602 StaticLookupMode static_mode,
1603 PrivateLookupMode private_mode) const {
1604 return InstanceKlass::find_method_impl(methods(),
1605 name,
1606 signature,
1607 overpass_mode,
1608 static_mode,
1609 private_mode);
1610 }
1611
1612 // Find looks up the name/signature in the local methods array
1613 // and filters on the overpass, static and private flags
1614 // This returns the first one found
1615 // note that the local methods array can have up to one overpass, one static
1616 // and one instance (private or not) with the same name/signature
1617 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1618 const Symbol* name,
1619 const Symbol* signature,
1620 OverpassLookupMode overpass_mode,
1621 StaticLookupMode static_mode,
1622 PrivateLookupMode private_mode) {
1623 return InstanceKlass::find_method_impl(methods,
1624 name,
1625 signature,
1626 overpass_mode,
1627 static_mode,
1628 private_mode);
1629 }
1630
1631 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1632 const Symbol* name,
1633 const Symbol* signature) {
1634 return InstanceKlass::find_method_impl(methods,
1635 name,
1636 signature,
1637 find_overpass,
1638 find_static,
1639 find_private);
1640 }
1641
1642 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1643 const Symbol* name,
1644 const Symbol* signature,
1645 OverpassLookupMode overpass_mode,
1646 StaticLookupMode static_mode,
1647 PrivateLookupMode private_mode) {
1648 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1649 return hit >= 0 ? methods->at(hit): NULL;
1650 }
1651
1652 // true if method matches signature and conforms to skipping_X conditions.
1653 static bool method_matches(const Method* m,
1654 const Symbol* signature,
1655 bool skipping_overpass,
1656 bool skipping_static,
1657 bool skipping_private) {
1658 return ((m->signature() == signature) &&
1659 (!skipping_overpass || !m->is_overpass()) &&
1660 (!skipping_static || !m->is_static()) &&
1661 (!skipping_private || !m->is_private()));
1662 }
1663
1664 // Used directly for default_methods to find the index into the
1665 // default_vtable_indices, and indirectly by find_method
1666 // find_method_index looks in the local methods array to return the index
1667 // of the matching name/signature. If, overpass methods are being ignored,
1668 // the search continues to find a potential non-overpass match. This capability
1669 // is important during method resolution to prefer a static method, for example,
1670 // over an overpass method.
1671 // There is the possibility in any _method's array to have the same name/signature
1672 // for a static method, an overpass method and a local instance method
1673 // To correctly catch a given method, the search criteria may need
1674 // to explicitly skip the other two. For local instance methods, it
1675 // is often necessary to skip private methods
1676 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1677 const Symbol* name,
1678 const Symbol* signature,
1679 OverpassLookupMode overpass_mode,
1680 StaticLookupMode static_mode,
1681 PrivateLookupMode private_mode) {
1682 const bool skipping_overpass = (overpass_mode == skip_overpass);
1683 const bool skipping_static = (static_mode == skip_static);
1684 const bool skipping_private = (private_mode == skip_private);
1685 const int hit = binary_search(methods, name);
1686 if (hit != -1) {
1687 const Method* const m = methods->at(hit);
1688
1689 // Do linear search to find matching signature. First, quick check
1690 // for common case, ignoring overpasses if requested.
1691 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1692 return hit;
1693 }
1694
1695 // search downwards through overloaded methods
1696 int i;
1697 for (i = hit - 1; i >= 0; --i) {
1698 const Method* const m = methods->at(i);
1699 assert(m->is_method(), "must be method");
1700 if (m->name() != name) {
1701 break;
1702 }
1703 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1704 return i;
1705 }
1706 }
1707 // search upwards
1708 for (i = hit + 1; i < methods->length(); ++i) {
1709 const Method* const m = methods->at(i);
1710 assert(m->is_method(), "must be method");
1711 if (m->name() != name) {
1712 break;
1713 }
1714 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1715 return i;
1716 }
1717 }
1718 // not found
1719 #ifdef ASSERT
1720 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1721 linear_search(methods, name, signature);
1722 assert(-1 == index, "binary search should have found entry %d", index);
1723 #endif
1724 }
1725 return -1;
1726 }
1727
1728 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1729 return find_method_by_name(methods(), name, end);
1730 }
1731
1732 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1733 const Symbol* name,
1734 int* end_ptr) {
1735 assert(end_ptr != NULL, "just checking");
1736 int start = binary_search(methods, name);
1737 int end = start + 1;
1738 if (start != -1) {
1739 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1740 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1741 *end_ptr = end;
1742 return start;
1743 }
1744 return -1;
1745 }
1746
1747 // uncached_lookup_method searches both the local class methods array and all
1748 // superclasses methods arrays, skipping any overpass methods in superclasses,
1749 // and possibly skipping private methods.
1750 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1751 const Symbol* signature,
1752 OverpassLookupMode overpass_mode,
1753 PrivateLookupMode private_mode) const {
1754 OverpassLookupMode overpass_local_mode = overpass_mode;
1755 const Klass* klass = this;
1756 while (klass != NULL) {
1757 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1758 signature,
1759 overpass_local_mode,
1760 find_static,
1761 private_mode);
1762 if (method != NULL) {
1763 return method;
1764 }
1765 klass = klass->super();
1766 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1767 }
1768 return NULL;
1769 }
1770
1771 #ifdef ASSERT
1772 // search through class hierarchy and return true if this class or
1773 // one of the superclasses was redefined
1774 bool InstanceKlass::has_redefined_this_or_super() const {
1775 const Klass* klass = this;
1776 while (klass != NULL) {
1777 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1778 return true;
1779 }
1780 klass = klass->super();
1781 }
1782 return false;
1783 }
1784 #endif
1785
1786 // lookup a method in the default methods list then in all transitive interfaces
1787 // Do NOT return private or static methods
1788 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1789 Symbol* signature) const {
1790 Method* m = NULL;
1791 if (default_methods() != NULL) {
1792 m = find_method(default_methods(), name, signature);
1793 }
1794 // Look up interfaces
1795 if (m == NULL) {
1796 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1797 }
1798 return m;
1799 }
1800
1801 // lookup a method in all the interfaces that this class implements
1802 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1803 // They should only be found in the initial InterfaceMethodRef
1804 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1805 Symbol* signature,
1806 DefaultsLookupMode defaults_mode) const {
1807 Array<Klass*>* all_ifs = transitive_interfaces();
1808 int num_ifs = all_ifs->length();
1809 InstanceKlass *ik = NULL;
1810 for (int i = 0; i < num_ifs; i++) {
1811 ik = InstanceKlass::cast(all_ifs->at(i));
1812 Method* m = ik->lookup_method(name, signature);
1813 if (m != NULL && m->is_public() && !m->is_static() &&
1814 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1815 return m;
1816 }
1817 }
1818 return NULL;
1819 }
1820
1821 /* jni_id_for_impl for jfieldIds only */
1822 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1823 MutexLocker ml(JfieldIdCreation_lock);
1824 // Retry lookup after we got the lock
1825 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1826 if (probe == NULL) {
1827 // Slow case, allocate new static field identifier
1828 probe = new JNIid(this, offset, jni_ids());
1829 set_jni_ids(probe);
1830 }
1831 return probe;
1832 }
1833
1834
1835 /* jni_id_for for jfieldIds only */
1836 JNIid* InstanceKlass::jni_id_for(int offset) {
1837 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1838 if (probe == NULL) {
1839 probe = jni_id_for_impl(offset);
1840 }
1841 return probe;
1842 }
1843
1844 u2 InstanceKlass::enclosing_method_data(int offset) const {
1845 const Array<jushort>* const inner_class_list = inner_classes();
1846 if (inner_class_list == NULL) {
1847 return 0;
1848 }
1849 const int length = inner_class_list->length();
1850 if (length % inner_class_next_offset == 0) {
1851 return 0;
1852 }
1853 const int index = length - enclosing_method_attribute_size;
1854 assert(offset < enclosing_method_attribute_size, "invalid offset");
1855 return inner_class_list->at(index + offset);
1856 }
1857
1858 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1859 u2 method_index) {
1860 Array<jushort>* inner_class_list = inner_classes();
1861 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1862 int length = inner_class_list->length();
1863 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1864 int index = length - enclosing_method_attribute_size;
1865 inner_class_list->at_put(
1866 index + enclosing_method_class_index_offset, class_index);
1867 inner_class_list->at_put(
1868 index + enclosing_method_method_index_offset, method_index);
1869 }
1870 }
1871
1872 // Lookup or create a jmethodID.
1873 // This code is called by the VMThread and JavaThreads so the
1874 // locking has to be done very carefully to avoid deadlocks
1875 // and/or other cache consistency problems.
1876 //
1877 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1878 size_t idnum = (size_t)method_h->method_idnum();
1879 jmethodID* jmeths = methods_jmethod_ids_acquire();
1880 size_t length = 0;
1881 jmethodID id = NULL;
1882
1883 // We use a double-check locking idiom here because this cache is
1884 // performance sensitive. In the normal system, this cache only
1885 // transitions from NULL to non-NULL which is safe because we use
1886 // release_set_methods_jmethod_ids() to advertise the new cache.
1887 // A partially constructed cache should never be seen by a racing
1888 // thread. We also use release_store() to save a new jmethodID
1889 // in the cache so a partially constructed jmethodID should never be
1890 // seen either. Cache reads of existing jmethodIDs proceed without a
1891 // lock, but cache writes of a new jmethodID requires uniqueness and
1892 // creation of the cache itself requires no leaks so a lock is
1893 // generally acquired in those two cases.
1894 //
1895 // If the RedefineClasses() API has been used, then this cache can
1896 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1897 // Cache creation requires no leaks and we require safety between all
1898 // cache accesses and freeing of the old cache so a lock is generally
1899 // acquired when the RedefineClasses() API has been used.
1900
1901 if (jmeths != NULL) {
1902 // the cache already exists
1903 if (!idnum_can_increment()) {
1904 // the cache can't grow so we can just get the current values
1905 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1906 } else {
1907 // cache can grow so we have to be more careful
1908 if (Threads::number_of_threads() == 0 ||
1909 SafepointSynchronize::is_at_safepoint()) {
1910 // we're single threaded or at a safepoint - no locking needed
1911 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1912 } else {
1913 MutexLocker ml(JmethodIdCreation_lock);
1914 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1915 }
1916 }
1917 }
1918 // implied else:
1919 // we need to allocate a cache so default length and id values are good
1920
1921 if (jmeths == NULL || // no cache yet
1922 length <= idnum || // cache is too short
1923 id == NULL) { // cache doesn't contain entry
1924
1925 // This function can be called by the VMThread so we have to do all
1926 // things that might block on a safepoint before grabbing the lock.
1927 // Otherwise, we can deadlock with the VMThread or have a cache
1928 // consistency issue. These vars keep track of what we might have
1929 // to free after the lock is dropped.
1930 jmethodID to_dealloc_id = NULL;
1931 jmethodID* to_dealloc_jmeths = NULL;
1932
1933 // may not allocate new_jmeths or use it if we allocate it
1934 jmethodID* new_jmeths = NULL;
1935 if (length <= idnum) {
1936 // allocate a new cache that might be used
1937 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1938 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1939 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1940 // cache size is stored in element[0], other elements offset by one
1941 new_jmeths[0] = (jmethodID)size;
1942 }
1943
1944 // allocate a new jmethodID that might be used
1945 jmethodID new_id = NULL;
1946 if (method_h->is_old() && !method_h->is_obsolete()) {
1947 // The method passed in is old (but not obsolete), we need to use the current version
1948 Method* current_method = method_with_idnum((int)idnum);
1949 assert(current_method != NULL, "old and but not obsolete, so should exist");
1950 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1951 } else {
1952 // It is the current version of the method or an obsolete method,
1953 // use the version passed in
1954 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1955 }
1956
1957 if (Threads::number_of_threads() == 0 ||
1958 SafepointSynchronize::is_at_safepoint()) {
1959 // we're single threaded or at a safepoint - no locking needed
1960 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1961 &to_dealloc_id, &to_dealloc_jmeths);
1962 } else {
1963 MutexLocker ml(JmethodIdCreation_lock);
1964 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1965 &to_dealloc_id, &to_dealloc_jmeths);
1966 }
1967
1968 // The lock has been dropped so we can free resources.
1969 // Free up either the old cache or the new cache if we allocated one.
1970 if (to_dealloc_jmeths != NULL) {
1971 FreeHeap(to_dealloc_jmeths);
1972 }
1973 // free up the new ID since it wasn't needed
1974 if (to_dealloc_id != NULL) {
1975 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1976 }
1977 }
1978 return id;
1979 }
1980
1981 // Figure out how many jmethodIDs haven't been allocated, and make
1982 // sure space for them is pre-allocated. This makes getting all
1983 // method ids much, much faster with classes with more than 8
1984 // methods, and has a *substantial* effect on performance with jvmti
1985 // code that loads all jmethodIDs for all classes.
1986 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1987 int new_jmeths = 0;
1988 int length = methods()->length();
1989 for (int index = start_offset; index < length; index++) {
1990 Method* m = methods()->at(index);
1991 jmethodID id = m->find_jmethod_id_or_null();
1992 if (id == NULL) {
1993 new_jmeths++;
1994 }
1995 }
1996 if (new_jmeths != 0) {
1997 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1998 }
1999 }
2000
2001 // Common code to fetch the jmethodID from the cache or update the
2002 // cache with the new jmethodID. This function should never do anything
2003 // that causes the caller to go to a safepoint or we can deadlock with
2004 // the VMThread or have cache consistency issues.
2005 //
2006 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2007 size_t idnum, jmethodID new_id,
2008 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2009 jmethodID** to_dealloc_jmeths_p) {
2010 assert(new_id != NULL, "sanity check");
2011 assert(to_dealloc_id_p != NULL, "sanity check");
2012 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2013 assert(Threads::number_of_threads() == 0 ||
2014 SafepointSynchronize::is_at_safepoint() ||
2015 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2016
2017 // reacquire the cache - we are locked, single threaded or at a safepoint
2018 jmethodID* jmeths = methods_jmethod_ids_acquire();
2019 jmethodID id = NULL;
2020 size_t length = 0;
2021
2022 if (jmeths == NULL || // no cache yet
2023 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2024 if (jmeths != NULL) {
2025 // copy any existing entries from the old cache
2026 for (size_t index = 0; index < length; index++) {
2027 new_jmeths[index+1] = jmeths[index+1];
2028 }
2029 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2030 }
2031 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2032 } else {
2033 // fetch jmethodID (if any) from the existing cache
2034 id = jmeths[idnum+1];
2035 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2036 }
2037 if (id == NULL) {
2038 // No matching jmethodID in the existing cache or we have a new
2039 // cache or we just grew the cache. This cache write is done here
2040 // by the first thread to win the foot race because a jmethodID
2041 // needs to be unique once it is generally available.
2042 id = new_id;
2043
2044 // The jmethodID cache can be read while unlocked so we have to
2045 // make sure the new jmethodID is complete before installing it
2046 // in the cache.
2047 OrderAccess::release_store(&jmeths[idnum+1], id);
2048 } else {
2049 *to_dealloc_id_p = new_id; // save new id for later delete
2050 }
2051 return id;
2052 }
2053
2054
2055 // Common code to get the jmethodID cache length and the jmethodID
2056 // value at index idnum if there is one.
2057 //
2058 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2059 size_t idnum, size_t *length_p, jmethodID* id_p) {
2060 assert(cache != NULL, "sanity check");
2061 assert(length_p != NULL, "sanity check");
2062 assert(id_p != NULL, "sanity check");
2063
2064 // cache size is stored in element[0], other elements offset by one
2065 *length_p = (size_t)cache[0];
2066 if (*length_p <= idnum) { // cache is too short
2067 *id_p = NULL;
2068 } else {
2069 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2070 }
2071 }
2072
2073
2074 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2075 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2076 size_t idnum = (size_t)method->method_idnum();
2077 jmethodID* jmeths = methods_jmethod_ids_acquire();
2078 size_t length; // length assigned as debugging crumb
2079 jmethodID id = NULL;
2080 if (jmeths != NULL && // If there is a cache
2081 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2082 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2083 }
2084 return id;
2085 }
2086
2087 inline DependencyContext InstanceKlass::dependencies() {
2088 DependencyContext dep_context(&_dep_context);
2089 return dep_context;
2090 }
2091
2092 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2093 return dependencies().mark_dependent_nmethods(changes);
2094 }
2095
2096 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2097 dependencies().add_dependent_nmethod(nm);
2098 }
2099
2100 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2101 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2102 }
2103
2104 #ifndef PRODUCT
2105 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2106 dependencies().print_dependent_nmethods(verbose);
2107 }
2108
2109 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2110 return dependencies().is_dependent_nmethod(nm);
2111 }
2112 #endif //PRODUCT
2113
2114 void InstanceKlass::clean_weak_instanceklass_links() {
2115 clean_implementors_list();
2116 clean_method_data();
2117
2118 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2119 DependencyContext dep_context(&_dep_context);
2120 dep_context.expunge_stale_entries();
2121 }
2122
2123 void InstanceKlass::clean_implementors_list() {
2124 assert(is_loader_alive(), "this klass should be live");
2125 if (is_interface()) {
2126 if (ClassUnloading) {
2127 Klass* impl = implementor();
2128 if (impl != NULL) {
2129 if (!impl->is_loader_alive()) {
2130 // remove this guy
2131 Klass** klass = adr_implementor();
2132 assert(klass != NULL, "null klass");
2133 if (klass != NULL) {
2134 *klass = NULL;
2135 }
2136 }
2137 }
2138 }
2139 }
2140 }
2141
2142 void InstanceKlass::clean_method_data() {
2143 for (int m = 0; m < methods()->length(); m++) {
2144 MethodData* mdo = methods()->at(m)->method_data();
2145 if (mdo != NULL) {
2146 mdo->clean_method_data(/*always_clean*/false);
2147 }
2148 }
2149 }
2150
2151 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2152 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2153 ResourceMark rm;
2154 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2155 return false;
2156 }
2157
2158 Array<Klass*>* local_interfaces = this->local_interfaces();
2159 if (local_interfaces != NULL) {
2160 int length = local_interfaces->length();
2161 for (int i = 0; i < length; i++) {
2162 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2163 if (!intf->has_passed_fingerprint_check()) {
2164 ResourceMark rm;
2165 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2166 return false;
2167 }
2168 }
2169 }
2170
2171 return true;
2172 }
2173
2174 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2175 #if INCLUDE_AOT
2176 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2177 if (CalculateClassFingerprint) {
2178 // (1) We are running AOT to generate a shared library.
2179 return true;
2180 }
2181 if (DumpSharedSpaces) {
2182 // (2) We are running -Xshare:dump to create a shared archive
2183 return true;
2184 }
2185 if (UseAOT && is_anonymous) {
2186 // (3) We are using AOT code from a shared library and see an anonymous class
2187 return true;
2188 }
2189 #endif
2190
2191 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2192 // but do not store the 64-bit fingerprint to save space.
2193 return false;
2194 }
2195
2196 bool InstanceKlass::has_stored_fingerprint() const {
2197 #if INCLUDE_AOT
2198 return should_store_fingerprint() || is_shared();
2199 #else
2200 return false;
2201 #endif
2202 }
2203
2204 uint64_t InstanceKlass::get_stored_fingerprint() const {
2205 address adr = adr_fingerprint();
2206 if (adr != NULL) {
2207 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2208 }
2209 return 0;
2210 }
2211
2212 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2213 address adr = adr_fingerprint();
2214 if (adr != NULL) {
2215 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2216
2217 ResourceMark rm;
2218 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2219 }
2220 }
2221
2222 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2223 Klass::metaspace_pointers_do(it);
2224
2225 if (log_is_enabled(Trace, cds)) {
2226 ResourceMark rm;
2227 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2228 }
2229
2230 it->push(&_annotations);
2231 it->push((Klass**)&_array_klasses);
2232 it->push(&_constants);
2233 it->push(&_inner_classes);
2234 it->push(&_array_name);
2235 #if INCLUDE_JVMTI
2236 it->push(&_previous_versions);
2237 #endif
2238 it->push(&_methods);
2239 it->push(&_default_methods);
2240 it->push(&_local_interfaces);
2241 it->push(&_transitive_interfaces);
2242 it->push(&_method_ordering);
2243 it->push(&_default_vtable_indices);
2244 it->push(&_fields);
2245
2246 if (itable_length() > 0) {
2247 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2248 int method_table_offset_in_words = ioe->offset()/wordSize;
2249 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2250 / itableOffsetEntry::size();
2251
2252 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2253 if (ioe->interface_klass() != NULL) {
2254 it->push(ioe->interface_klass_addr());
2255 itableMethodEntry* ime = ioe->first_method_entry(this);
2256 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2257 for (int index = 0; index < n; index ++) {
2258 it->push(ime[index].method_addr());
2259 }
2260 }
2261 }
2262 }
2263
2264 it->push(&_nest_members);
2265 }
2266
2267 void InstanceKlass::remove_unshareable_info() {
2268 Klass::remove_unshareable_info();
2269
2270 if (is_in_error_state()) {
2271 // Classes are attempted to link during dumping and may fail,
2272 // but these classes are still in the dictionary and class list in CLD.
2273 // Check in_error state first because in_error is > linked state, so
2274 // is_linked() is true.
2275 // If there's a linking error, there is nothing else to remove.
2276 return;
2277 }
2278
2279 // Unlink the class
2280 if (is_linked()) {
2281 unlink_class();
2282 }
2283 init_implementor();
2284
2285 constants()->remove_unshareable_info();
2286
2287 for (int i = 0; i < methods()->length(); i++) {
2288 Method* m = methods()->at(i);
2289 m->remove_unshareable_info();
2290 }
2291
2292 // do array classes also.
2293 if (array_klasses() != NULL) {
2294 array_klasses()->remove_unshareable_info();
2295 }
2296
2297 // These are not allocated from metaspace, but they should should all be empty
2298 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2299 guarantee(_source_debug_extension == NULL, "must be");
2300 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2301 guarantee(_osr_nmethods_head == NULL, "must be");
2302
2303 #if INCLUDE_JVMTI
2304 guarantee(_breakpoints == NULL, "must be");
2305 guarantee(_previous_versions == NULL, "must be");
2306 #endif
2307
2308 _init_thread = NULL;
2309 _methods_jmethod_ids = NULL;
2310 _jni_ids = NULL;
2311 _oop_map_cache = NULL;
2312 // clear _nest_host to ensure re-load at runtime
2313 _nest_host = NULL;
2314 }
2315
2316 void InstanceKlass::remove_java_mirror() {
2317 Klass::remove_java_mirror();
2318
2319 // do array classes also.
2320 if (array_klasses() != NULL) {
2321 array_klasses()->remove_java_mirror();
2322 }
2323 }
2324
2325 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2326 set_package(loader_data, CHECK);
2327 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2328
2329 Array<Method*>* methods = this->methods();
2330 int num_methods = methods->length();
2331 for (int index2 = 0; index2 < num_methods; ++index2) {
2332 methodHandle m(THREAD, methods->at(index2));
2333 m->restore_unshareable_info(CHECK);
2334 }
2335 if (JvmtiExport::has_redefined_a_class()) {
2336 // Reinitialize vtable because RedefineClasses may have changed some
2337 // entries in this vtable for super classes so the CDS vtable might
2338 // point to old or obsolete entries. RedefineClasses doesn't fix up
2339 // vtables in the shared system dictionary, only the main one.
2340 // It also redefines the itable too so fix that too.
2341 ResourceMark rm(THREAD);
2342 vtable().initialize_vtable(false, CHECK);
2343 itable().initialize_itable(false, CHECK);
2344 }
2345
2346 // restore constant pool resolved references
2347 constants()->restore_unshareable_info(CHECK);
2348
2349 if (array_klasses() != NULL) {
2350 // Array classes have null protection domain.
2351 // --> see ArrayKlass::complete_create_array_klass()
2352 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2353 }
2354 }
2355
2356 // returns true IFF is_in_error_state() has been changed as a result of this call.
2357 bool InstanceKlass::check_sharing_error_state() {
2358 assert(DumpSharedSpaces, "should only be called during dumping");
2359 bool old_state = is_in_error_state();
2360
2361 if (!is_in_error_state()) {
2362 bool bad = false;
2363 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2364 if (sup->is_in_error_state()) {
2365 bad = true;
2366 break;
2367 }
2368 }
2369 if (!bad) {
2370 Array<Klass*>* interfaces = transitive_interfaces();
2371 for (int i = 0; i < interfaces->length(); i++) {
2372 Klass* iface = interfaces->at(i);
2373 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2374 bad = true;
2375 break;
2376 }
2377 }
2378 }
2379
2380 if (bad) {
2381 set_in_error_state();
2382 }
2383 }
2384
2385 return (old_state != is_in_error_state());
2386 }
2387
2388 #if INCLUDE_JVMTI
2389 static void clear_all_breakpoints(Method* m) {
2390 m->clear_all_breakpoints();
2391 }
2392 #endif
2393
2394 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2395 // notify the debugger
2396 if (JvmtiExport::should_post_class_unload()) {
2397 JvmtiExport::post_class_unload(ik);
2398 }
2399
2400 // notify ClassLoadingService of class unload
2401 ClassLoadingService::notify_class_unloaded(ik);
2402 }
2403
2404 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2405 // Clean up C heap
2406 ik->release_C_heap_structures();
2407 ik->constants()->release_C_heap_structures();
2408 }
2409
2410 void InstanceKlass::release_C_heap_structures() {
2411 // Can't release the constant pool here because the constant pool can be
2412 // deallocated separately from the InstanceKlass for default methods and
2413 // redefine classes.
2414
2415 // Deallocate oop map cache
2416 if (_oop_map_cache != NULL) {
2417 delete _oop_map_cache;
2418 _oop_map_cache = NULL;
2419 }
2420
2421 // Deallocate JNI identifiers for jfieldIDs
2422 JNIid::deallocate(jni_ids());
2423 set_jni_ids(NULL);
2424
2425 jmethodID* jmeths = methods_jmethod_ids_acquire();
2426 if (jmeths != (jmethodID*)NULL) {
2427 release_set_methods_jmethod_ids(NULL);
2428 FreeHeap(jmeths);
2429 }
2430
2431 // Release dependencies.
2432 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2433 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2434 // context can contain live dependencies, since there's a race between nmethod &
2435 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2436 // dependencies aren't removed from the context associated with the class (see
2437 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2438 // live dependencies pointing to unloaded nmethods and causes a crash in
2439 // DC::remove_all_dependents() when it touches unloaded nmethod.
2440 dependencies().wipe();
2441
2442 #if INCLUDE_JVMTI
2443 // Deallocate breakpoint records
2444 if (breakpoints() != 0x0) {
2445 methods_do(clear_all_breakpoints);
2446 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2447 }
2448
2449 // deallocate the cached class file
2450 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2451 os::free(_cached_class_file);
2452 _cached_class_file = NULL;
2453 }
2454 #endif
2455
2456 // Decrement symbol reference counts associated with the unloaded class.
2457 if (_name != NULL) _name->decrement_refcount();
2458 // unreference array name derived from this class name (arrays of an unloaded
2459 // class can't be referenced anymore).
2460 if (_array_name != NULL) _array_name->decrement_refcount();
2461 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2462 }
2463
2464 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2465 if (array == NULL) {
2466 _source_debug_extension = NULL;
2467 } else {
2468 // Adding one to the attribute length in order to store a null terminator
2469 // character could cause an overflow because the attribute length is
2470 // already coded with an u4 in the classfile, but in practice, it's
2471 // unlikely to happen.
2472 assert((length+1) > length, "Overflow checking");
2473 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2474 for (int i = 0; i < length; i++) {
2475 sde[i] = array[i];
2476 }
2477 sde[length] = '\0';
2478 _source_debug_extension = sde;
2479 }
2480 }
2481
2482 const char* InstanceKlass::signature_name() const {
2483 int hash_len = 0;
2484 char hash_buf[40];
2485
2486 // If this is an anonymous class, append a hash to make the name unique
2487 if (is_anonymous()) {
2488 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2489 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2490 hash_len = (int)strlen(hash_buf);
2491 }
2492
2493 // Get the internal name as a c string
2494 const char* src = (const char*) (name()->as_C_string());
2495 const int src_length = (int)strlen(src);
2496
2497 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2498
2499 // Add L as type indicator
2500 int dest_index = 0;
2501 dest[dest_index++] = 'L';
2502
2503 // Add the actual class name
2504 for (int src_index = 0; src_index < src_length; ) {
2505 dest[dest_index++] = src[src_index++];
2506 }
2507
2508 // If we have a hash, append it
2509 for (int hash_index = 0; hash_index < hash_len; ) {
2510 dest[dest_index++] = hash_buf[hash_index++];
2511 }
2512
2513 // Add the semicolon and the NULL
2514 dest[dest_index++] = ';';
2515 dest[dest_index] = '\0';
2516 return dest;
2517 }
2518
2519 // Used to obtain the package name from a fully qualified class name.
2520 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2521 if (name == NULL) {
2522 return NULL;
2523 } else {
2524 if (name->utf8_length() <= 0) {
2525 return NULL;
2526 }
2527 ResourceMark rm;
2528 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2529 if (package_name == NULL) {
2530 return NULL;
2531 }
2532 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2533 return pkg_name;
2534 }
2535 }
2536
2537 ModuleEntry* InstanceKlass::module() const {
2538 if (!in_unnamed_package()) {
2539 return _package_entry->module();
2540 }
2541 const Klass* host = host_klass();
2542 if (host == NULL) {
2543 return class_loader_data()->unnamed_module();
2544 }
2545 return host->class_loader_data()->unnamed_module();
2546 }
2547
2548 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2549
2550 // ensure java/ packages only loaded by boot or platform builtin loaders
2551 check_prohibited_package(name(), loader_data, CHECK);
2552
2553 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2554
2555 if (pkg_name != NULL && loader_data != NULL) {
2556
2557 // Find in class loader's package entry table.
2558 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2559
2560 // If the package name is not found in the loader's package
2561 // entry table, it is an indication that the package has not
2562 // been defined. Consider it defined within the unnamed module.
2563 if (_package_entry == NULL) {
2564 ResourceMark rm;
2565
2566 if (!ModuleEntryTable::javabase_defined()) {
2567 // Before java.base is defined during bootstrapping, define all packages in
2568 // the java.base module. If a non-java.base package is erroneously placed
2569 // in the java.base module it will be caught later when java.base
2570 // is defined by ModuleEntryTable::verify_javabase_packages check.
2571 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2572 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2573 } else {
2574 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2575 _package_entry = loader_data->packages()->lookup(pkg_name,
2576 loader_data->unnamed_module());
2577 }
2578
2579 // A package should have been successfully created
2580 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2581 name()->as_C_string(), loader_data->loader_name_and_id());
2582 }
2583
2584 if (log_is_enabled(Debug, module)) {
2585 ResourceMark rm;
2586 ModuleEntry* m = _package_entry->module();
2587 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2588 external_name(),
2589 pkg_name->as_C_string(),
2590 loader_data->loader_name_and_id(),
2591 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2592 }
2593 } else {
2594 ResourceMark rm;
2595 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2596 external_name(),
2597 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2598 UNNAMED_MODULE);
2599 }
2600 }
2601
2602
2603 // different versions of is_same_class_package
2604
2605 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2606 oop classloader1 = this->class_loader();
2607 PackageEntry* classpkg1 = this->package();
2608 if (class2->is_objArray_klass()) {
2609 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2610 }
2611
2612 oop classloader2;
2613 PackageEntry* classpkg2;
2614 if (class2->is_instance_klass()) {
2615 classloader2 = class2->class_loader();
2616 classpkg2 = class2->package();
2617 } else {
2618 assert(class2->is_typeArray_klass(), "should be type array");
2619 classloader2 = NULL;
2620 classpkg2 = NULL;
2621 }
2622
2623 // Same package is determined by comparing class loader
2624 // and package entries. Both must be the same. This rule
2625 // applies even to classes that are defined in the unnamed
2626 // package, they still must have the same class loader.
2627 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2628 return true;
2629 }
2630
2631 return false;
2632 }
2633
2634 // return true if this class and other_class are in the same package. Classloader
2635 // and classname information is enough to determine a class's package
2636 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2637 const Symbol* other_class_name) const {
2638 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2639 return false;
2640 }
2641 if (name()->fast_compare(other_class_name) == 0) {
2642 return true;
2643 }
2644
2645 {
2646 ResourceMark rm;
2647
2648 bool bad_class_name = false;
2649 const char* other_pkg =
2650 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2651 if (bad_class_name) {
2652 return false;
2653 }
2654 // Check that package_from_name() returns NULL, not "", if there is no package.
2655 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2656
2657 const Symbol* const this_package_name =
2658 this->package() != NULL ? this->package()->name() : NULL;
2659
2660 if (this_package_name == NULL || other_pkg == NULL) {
2661 // One of the two doesn't have a package. Only return true if the other
2662 // one also doesn't have a package.
2663 return (const char*)this_package_name == other_pkg;
2664 }
2665
2666 // Check if package is identical
2667 return this_package_name->equals(other_pkg);
2668 }
2669 }
2670
2671 // Returns true iff super_method can be overridden by a method in targetclassname
2672 // See JLS 3rd edition 8.4.6.1
2673 // Assumes name-signature match
2674 // "this" is InstanceKlass of super_method which must exist
2675 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2676 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2677 // Private methods can not be overridden
2678 if (super_method->is_private()) {
2679 return false;
2680 }
2681 // If super method is accessible, then override
2682 if ((super_method->is_protected()) ||
2683 (super_method->is_public())) {
2684 return true;
2685 }
2686 // Package-private methods are not inherited outside of package
2687 assert(super_method->is_package_private(), "must be package private");
2688 return(is_same_class_package(targetclassloader(), targetclassname));
2689 }
2690
2691 // Only boot and platform class loaders can define classes in "java/" packages.
2692 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2693 ClassLoaderData* loader_data,
2694 TRAPS) {
2695 if (!loader_data->is_boot_class_loader_data() &&
2696 !loader_data->is_platform_class_loader_data() &&
2697 class_name != NULL) {
2698 ResourceMark rm(THREAD);
2699 char* name = class_name->as_C_string();
2700 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2701 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2702 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2703 name = pkg_name->as_C_string();
2704 const char* class_loader_name = loader_data->loader_name_and_id();
2705 StringUtils::replace_no_expand(name, "/", ".");
2706 const char* msg_text1 = "Class loader (instance of): ";
2707 const char* msg_text2 = " tried to load prohibited package name: ";
2708 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2709 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2710 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2711 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2712 }
2713 }
2714 return;
2715 }
2716
2717 // tell if two classes have the same enclosing class (at package level)
2718 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2719 if (class2 == this) return true;
2720 if (!class2->is_instance_klass()) return false;
2721
2722 // must be in same package before we try anything else
2723 if (!is_same_class_package(class2))
2724 return false;
2725
2726 // As long as there is an outer_this.getEnclosingClass,
2727 // shift the search outward.
2728 const InstanceKlass* outer_this = this;
2729 for (;;) {
2730 // As we walk along, look for equalities between outer_this and class2.
2731 // Eventually, the walks will terminate as outer_this stops
2732 // at the top-level class around the original class.
2733 bool ignore_inner_is_member;
2734 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2735 CHECK_false);
2736 if (next == NULL) break;
2737 if (next == class2) return true;
2738 outer_this = InstanceKlass::cast(next);
2739 }
2740
2741 // Now do the same for class2.
2742 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2743 for (;;) {
2744 bool ignore_inner_is_member;
2745 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2746 CHECK_false);
2747 if (next == NULL) break;
2748 // Might as well check the new outer against all available values.
2749 if (next == this) return true;
2750 if (next == outer_this) return true;
2751 outer2 = InstanceKlass::cast(next);
2752 }
2753
2754 // If by this point we have not found an equality between the
2755 // two classes, we know they are in separate package members.
2756 return false;
2757 }
2758
2759 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2760 constantPoolHandle i_cp(THREAD, constants());
2761 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2762 int ioff = iter.inner_class_info_index();
2763 if (ioff != 0) {
2764 // Check to see if the name matches the class we're looking for
2765 // before attempting to find the class.
2766 if (i_cp->klass_name_at_matches(this, ioff)) {
2767 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2768 if (this == inner_klass) {
2769 *ooff = iter.outer_class_info_index();
2770 *noff = iter.inner_name_index();
2771 return true;
2772 }
2773 }
2774 }
2775 }
2776 return false;
2777 }
2778
2779 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2780 InstanceKlass* outer_klass = NULL;
2781 *inner_is_member = false;
2782 int ooff = 0, noff = 0;
2783 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2784 if (has_inner_classes_attr) {
2785 constantPoolHandle i_cp(THREAD, constants());
2786 if (ooff != 0) {
2787 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2788 outer_klass = InstanceKlass::cast(ok);
2789 *inner_is_member = true;
2790 }
2791 if (NULL == outer_klass) {
2792 // It may be anonymous; try for that.
2793 int encl_method_class_idx = enclosing_method_class_index();
2794 if (encl_method_class_idx != 0) {
2795 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2796 outer_klass = InstanceKlass::cast(ok);
2797 *inner_is_member = false;
2798 }
2799 }
2800 }
2801
2802 // If no inner class attribute found for this class.
2803 if (NULL == outer_klass) return NULL;
2804
2805 // Throws an exception if outer klass has not declared k as an inner klass
2806 // We need evidence that each klass knows about the other, or else
2807 // the system could allow a spoof of an inner class to gain access rights.
2808 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2809 return outer_klass;
2810 }
2811
2812 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2813 jint access = access_flags().as_int();
2814
2815 // But check if it happens to be member class.
2816 InnerClassesIterator iter(this);
2817 for (; !iter.done(); iter.next()) {
2818 int ioff = iter.inner_class_info_index();
2819 // Inner class attribute can be zero, skip it.
2820 // Strange but true: JVM spec. allows null inner class refs.
2821 if (ioff == 0) continue;
2822
2823 // only look at classes that are already loaded
2824 // since we are looking for the flags for our self.
2825 Symbol* inner_name = constants()->klass_name_at(ioff);
2826 if (name() == inner_name) {
2827 // This is really a member class.
2828 access = iter.inner_access_flags();
2829 break;
2830 }
2831 }
2832 // Remember to strip ACC_SUPER bit
2833 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2834 }
2835
2836 jint InstanceKlass::jvmti_class_status() const {
2837 jint result = 0;
2838
2839 if (is_linked()) {
2840 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2841 }
2842
2843 if (is_initialized()) {
2844 assert(is_linked(), "Class status is not consistent");
2845 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2846 }
2847 if (is_in_error_state()) {
2848 result |= JVMTI_CLASS_STATUS_ERROR;
2849 }
2850 return result;
2851 }
2852
2853 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2854 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2855 int method_table_offset_in_words = ioe->offset()/wordSize;
2856 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2857 / itableOffsetEntry::size();
2858
2859 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2860 // If the interface isn't implemented by the receiver class,
2861 // the VM should throw IncompatibleClassChangeError.
2862 if (cnt >= nof_interfaces) {
2863 ResourceMark rm(THREAD);
2864 stringStream ss;
2865 bool same_module = (module() == holder->module());
2866 ss.print("Receiver class %s does not implement "
2867 "the interface %s defining the method to be called "
2868 "(%s%s%s)",
2869 external_name(), holder->external_name(),
2870 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2871 (same_module) ? "" : "; ",
2872 (same_module) ? "" : holder->class_in_module_of_loader());
2873 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2874 }
2875
2876 Klass* ik = ioe->interface_klass();
2877 if (ik == holder) break;
2878 }
2879
2880 itableMethodEntry* ime = ioe->first_method_entry(this);
2881 Method* m = ime[index].method();
2882 if (m == NULL) {
2883 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2884 }
2885 return m;
2886 }
2887
2888
2889 #if INCLUDE_JVMTI
2890 // update default_methods for redefineclasses for methods that are
2891 // not yet in the vtable due to concurrent subclass define and superinterface
2892 // redefinition
2893 // Note: those in the vtable, should have been updated via adjust_method_entries
2894 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2895 // search the default_methods for uses of either obsolete or EMCP methods
2896 if (default_methods() != NULL) {
2897 for (int index = 0; index < default_methods()->length(); index ++) {
2898 Method* old_method = default_methods()->at(index);
2899 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2900 continue; // skip uninteresting entries
2901 }
2902 assert(!old_method->is_deleted(), "default methods may not be deleted");
2903
2904 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2905
2906 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2907 assert(old_method != new_method, "sanity check");
2908
2909 default_methods()->at_put(index, new_method);
2910 if (log_is_enabled(Info, redefine, class, update)) {
2911 ResourceMark rm;
2912 if (!(*trace_name_printed)) {
2913 log_info(redefine, class, update)
2914 ("adjust: klassname=%s default methods from name=%s",
2915 external_name(), old_method->method_holder()->external_name());
2916 *trace_name_printed = true;
2917 }
2918 log_debug(redefine, class, update, vtables)
2919 ("default method update: %s(%s) ",
2920 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2921 }
2922 }
2923 }
2924 }
2925 #endif // INCLUDE_JVMTI
2926
2927 // On-stack replacement stuff
2928 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2929 // only one compilation can be active
2930 {
2931 // This is a short non-blocking critical region, so the no safepoint check is ok.
2932 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2933 assert(n->is_osr_method(), "wrong kind of nmethod");
2934 n->set_osr_link(osr_nmethods_head());
2935 set_osr_nmethods_head(n);
2936 // Raise the highest osr level if necessary
2937 if (TieredCompilation) {
2938 Method* m = n->method();
2939 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2940 }
2941 }
2942
2943 // Get rid of the osr methods for the same bci that have lower levels.
2944 if (TieredCompilation) {
2945 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2946 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2947 if (inv != NULL && inv->is_in_use()) {
2948 inv->make_not_entrant();
2949 }
2950 }
2951 }
2952 }
2953
2954 // Remove osr nmethod from the list. Return true if found and removed.
2955 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2956 // This is a short non-blocking critical region, so the no safepoint check is ok.
2957 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2958 assert(n->is_osr_method(), "wrong kind of nmethod");
2959 nmethod* last = NULL;
2960 nmethod* cur = osr_nmethods_head();
2961 int max_level = CompLevel_none; // Find the max comp level excluding n
2962 Method* m = n->method();
2963 // Search for match
2964 bool found = false;
2965 while(cur != NULL && cur != n) {
2966 if (TieredCompilation && m == cur->method()) {
2967 // Find max level before n
2968 max_level = MAX2(max_level, cur->comp_level());
2969 }
2970 last = cur;
2971 cur = cur->osr_link();
2972 }
2973 nmethod* next = NULL;
2974 if (cur == n) {
2975 found = true;
2976 next = cur->osr_link();
2977 if (last == NULL) {
2978 // Remove first element
2979 set_osr_nmethods_head(next);
2980 } else {
2981 last->set_osr_link(next);
2982 }
2983 }
2984 n->set_osr_link(NULL);
2985 if (TieredCompilation) {
2986 cur = next;
2987 while (cur != NULL) {
2988 // Find max level after n
2989 if (m == cur->method()) {
2990 max_level = MAX2(max_level, cur->comp_level());
2991 }
2992 cur = cur->osr_link();
2993 }
2994 m->set_highest_osr_comp_level(max_level);
2995 }
2996 return found;
2997 }
2998
2999 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3000 // This is a short non-blocking critical region, so the no safepoint check is ok.
3001 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3002 nmethod* osr = osr_nmethods_head();
3003 int found = 0;
3004 while (osr != NULL) {
3005 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3006 if (osr->method() == m) {
3007 osr->mark_for_deoptimization();
3008 found++;
3009 }
3010 osr = osr->osr_link();
3011 }
3012 return found;
3013 }
3014
3015 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3016 // This is a short non-blocking critical region, so the no safepoint check is ok.
3017 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3018 nmethod* osr = osr_nmethods_head();
3019 nmethod* best = NULL;
3020 while (osr != NULL) {
3021 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3022 // There can be a time when a c1 osr method exists but we are waiting
3023 // for a c2 version. When c2 completes its osr nmethod we will trash
3024 // the c1 version and only be able to find the c2 version. However
3025 // while we overflow in the c1 code at back branches we don't want to
3026 // try and switch to the same code as we are already running
3027
3028 if (osr->method() == m &&
3029 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3030 if (match_level) {
3031 if (osr->comp_level() == comp_level) {
3032 // Found a match - return it.
3033 return osr;
3034 }
3035 } else {
3036 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3037 if (osr->comp_level() == CompLevel_highest_tier) {
3038 // Found the best possible - return it.
3039 return osr;
3040 }
3041 best = osr;
3042 }
3043 }
3044 }
3045 osr = osr->osr_link();
3046 }
3047 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3048 return best;
3049 }
3050 return NULL;
3051 }
3052
3053 // -----------------------------------------------------------------------------------------------------
3054 // Printing
3055
3056 #ifndef PRODUCT
3057
3058 #define BULLET " - "
3059
3060 static const char* state_names[] = {
3061 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3062 };
3063
3064 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3065 for (int i = 0; i < len; i++) {
3066 intptr_t e = start[i];
3067 st->print("%d : " INTPTR_FORMAT, i, e);
3068 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3069 st->print(" ");
3070 ((Metadata*)e)->print_value_on(st);
3071 }
3072 st->cr();
3073 }
3074 }
3075
3076 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3077 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3078 }
3079
3080 void InstanceKlass::print_on(outputStream* st) const {
3081 assert(is_klass(), "must be klass");
3082 Klass::print_on(st);
3083
3084 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3085 st->print(BULLET"klass size: %d", size()); st->cr();
3086 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3087 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3088 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3089 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3090 st->print(BULLET"sub: ");
3091 Klass* sub = subklass();
3092 int n;
3093 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3094 if (n < MaxSubklassPrintSize) {
3095 sub->print_value_on(st);
3096 st->print(" ");
3097 }
3098 }
3099 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3100 st->cr();
3101
3102 if (is_interface()) {
3103 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3104 if (nof_implementors() == 1) {
3105 st->print_cr(BULLET"implementor: ");
3106 st->print(" ");
3107 implementor()->print_value_on(st);
3108 st->cr();
3109 }
3110 }
3111
3112 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3113 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3114 if (Verbose || WizardMode) {
3115 Array<Method*>* method_array = methods();
3116 for (int i = 0; i < method_array->length(); i++) {
3117 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3118 }
3119 }
3120 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3121 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3122 if (Verbose && default_methods() != NULL) {
3123 Array<Method*>* method_array = default_methods();
3124 for (int i = 0; i < method_array->length(); i++) {
3125 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3126 }
3127 }
3128 if (default_vtable_indices() != NULL) {
3129 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3130 }
3131 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3132 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3133 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3134 if (class_loader_data() != NULL) {
3135 st->print(BULLET"class loader data: ");
3136 class_loader_data()->print_value_on(st);
3137 st->cr();
3138 }
3139 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3140 if (source_file_name() != NULL) {
3141 st->print(BULLET"source file: ");
3142 source_file_name()->print_value_on(st);
3143 st->cr();
3144 }
3145 if (source_debug_extension() != NULL) {
3146 st->print(BULLET"source debug extension: ");
3147 st->print("%s", source_debug_extension());
3148 st->cr();
3149 }
3150 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3151 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3152 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3153 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3154 {
3155 bool have_pv = false;
3156 // previous versions are linked together through the InstanceKlass
3157 for (InstanceKlass* pv_node = previous_versions();
3158 pv_node != NULL;
3159 pv_node = pv_node->previous_versions()) {
3160 if (!have_pv)
3161 st->print(BULLET"previous version: ");
3162 have_pv = true;
3163 pv_node->constants()->print_value_on(st);
3164 }
3165 if (have_pv) st->cr();
3166 }
3167
3168 if (generic_signature() != NULL) {
3169 st->print(BULLET"generic signature: ");
3170 generic_signature()->print_value_on(st);
3171 st->cr();
3172 }
3173 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3174 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3175 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3176 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3177 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3178 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3179 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3180 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3181 FieldPrinter print_static_field(st);
3182 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3183 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3184 FieldPrinter print_nonstatic_field(st);
3185 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3186 ik->do_nonstatic_fields(&print_nonstatic_field);
3187
3188 st->print(BULLET"non-static oop maps: ");
3189 OopMapBlock* map = start_of_nonstatic_oop_maps();
3190 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3191 while (map < end_map) {
3192 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3193 map++;
3194 }
3195 st->cr();
3196 }
3197
3198 #endif //PRODUCT
3199
3200 void InstanceKlass::print_value_on(outputStream* st) const {
3201 assert(is_klass(), "must be klass");
3202 if (Verbose || WizardMode) access_flags().print_on(st);
3203 name()->print_value_on(st);
3204 }
3205
3206 #ifndef PRODUCT
3207
3208 void FieldPrinter::do_field(fieldDescriptor* fd) {
3209 _st->print(BULLET);
3210 if (_obj == NULL) {
3211 fd->print_on(_st);
3212 _st->cr();
3213 } else {
3214 fd->print_on_for(_st, _obj);
3215 _st->cr();
3216 }
3217 }
3218
3219
3220 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3221 Klass::oop_print_on(obj, st);
3222
3223 if (this == SystemDictionary::String_klass()) {
3224 typeArrayOop value = java_lang_String::value(obj);
3225 juint length = java_lang_String::length(obj);
3226 if (value != NULL &&
3227 value->is_typeArray() &&
3228 length <= (juint) value->length()) {
3229 st->print(BULLET"string: ");
3230 java_lang_String::print(obj, st);
3231 st->cr();
3232 if (!WizardMode) return; // that is enough
3233 }
3234 }
3235
3236 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3237 FieldPrinter print_field(st, obj);
3238 do_nonstatic_fields(&print_field);
3239
3240 if (this == SystemDictionary::Class_klass()) {
3241 st->print(BULLET"signature: ");
3242 java_lang_Class::print_signature(obj, st);
3243 st->cr();
3244 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3245 st->print(BULLET"fake entry for mirror: ");
3246 mirrored_klass->print_value_on_maybe_null(st);
3247 st->cr();
3248 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3249 st->print(BULLET"fake entry for array: ");
3250 array_klass->print_value_on_maybe_null(st);
3251 st->cr();
3252 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3253 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3254 Klass* real_klass = java_lang_Class::as_Klass(obj);
3255 if (real_klass != NULL && real_klass->is_instance_klass()) {
3256 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3257 }
3258 } else if (this == SystemDictionary::MethodType_klass()) {
3259 st->print(BULLET"signature: ");
3260 java_lang_invoke_MethodType::print_signature(obj, st);
3261 st->cr();
3262 }
3263 }
3264
3265 #endif //PRODUCT
3266
3267 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3268 st->print("a ");
3269 name()->print_value_on(st);
3270 obj->print_address_on(st);
3271 if (this == SystemDictionary::String_klass()
3272 && java_lang_String::value(obj) != NULL) {
3273 ResourceMark rm;
3274 int len = java_lang_String::length(obj);
3275 int plen = (len < 24 ? len : 12);
3276 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3277 st->print(" = \"%s\"", str);
3278 if (len > plen)
3279 st->print("...[%d]", len);
3280 } else if (this == SystemDictionary::Class_klass()) {
3281 Klass* k = java_lang_Class::as_Klass(obj);
3282 st->print(" = ");
3283 if (k != NULL) {
3284 k->print_value_on(st);
3285 } else {
3286 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3287 st->print("%s", tname ? tname : "type?");
3288 }
3289 } else if (this == SystemDictionary::MethodType_klass()) {
3290 st->print(" = ");
3291 java_lang_invoke_MethodType::print_signature(obj, st);
3292 } else if (java_lang_boxing_object::is_instance(obj)) {
3293 st->print(" = ");
3294 java_lang_boxing_object::print(obj, st);
3295 } else if (this == SystemDictionary::LambdaForm_klass()) {
3296 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3297 if (vmentry != NULL) {
3298 st->print(" => ");
3299 vmentry->print_value_on(st);
3300 }
3301 } else if (this == SystemDictionary::MemberName_klass()) {
3302 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3303 if (vmtarget != NULL) {
3304 st->print(" = ");
3305 vmtarget->print_value_on(st);
3306 } else {
3307 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3308 st->print(".");
3309 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3310 }
3311 }
3312 }
3313
3314 const char* InstanceKlass::internal_name() const {
3315 return external_name();
3316 }
3317
3318 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3319 const char* module_name,
3320 const ClassFileStream* cfs) const {
3321 if (!log_is_enabled(Info, class, load)) {
3322 return;
3323 }
3324
3325 ResourceMark rm;
3326 LogMessage(class, load) msg;
3327 stringStream info_stream;
3328
3329 // Name and class hierarchy info
3330 info_stream.print("%s", external_name());
3331
3332 // Source
3333 if (cfs != NULL) {
3334 if (cfs->source() != NULL) {
3335 if (module_name != NULL) {
3336 if (ClassLoader::is_modules_image(cfs->source())) {
3337 info_stream.print(" source: jrt:/%s", module_name);
3338 } else {
3339 info_stream.print(" source: %s", cfs->source());
3340 }
3341 } else {
3342 info_stream.print(" source: %s", cfs->source());
3343 }
3344 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3345 Thread* THREAD = Thread::current();
3346 Klass* caller =
3347 THREAD->is_Java_thread()
3348 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3349 : NULL;
3350 // caller can be NULL, for example, during a JVMTI VM_Init hook
3351 if (caller != NULL) {
3352 info_stream.print(" source: instance of %s", caller->external_name());
3353 } else {
3354 // source is unknown
3355 }
3356 } else {
3357 oop class_loader = loader_data->class_loader();
3358 info_stream.print(" source: %s", class_loader->klass()->external_name());
3359 }
3360 } else {
3361 info_stream.print(" source: shared objects file");
3362 }
3363
3364 msg.info("%s", info_stream.as_string());
3365
3366 if (log_is_enabled(Debug, class, load)) {
3367 stringStream debug_stream;
3368
3369 // Class hierarchy info
3370 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3371 p2i(this), p2i(superklass()));
3372
3373 // Interfaces
3374 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3375 debug_stream.print(" interfaces:");
3376 int length = local_interfaces()->length();
3377 for (int i = 0; i < length; i++) {
3378 debug_stream.print(" " INTPTR_FORMAT,
3379 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3380 }
3381 }
3382
3383 // Class loader
3384 debug_stream.print(" loader: [");
3385 loader_data->print_value_on(&debug_stream);
3386 debug_stream.print("]");
3387
3388 // Classfile checksum
3389 if (cfs) {
3390 debug_stream.print(" bytes: %d checksum: %08x",
3391 cfs->length(),
3392 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3393 cfs->length()));
3394 }
3395
3396 msg.debug("%s", debug_stream.as_string());
3397 }
3398 }
3399
3400 #if INCLUDE_SERVICES
3401 // Size Statistics
3402 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3403 Klass::collect_statistics(sz);
3404
3405 sz->_inst_size = wordSize * size_helper();
3406 sz->_vtab_bytes = wordSize * vtable_length();
3407 sz->_itab_bytes = wordSize * itable_length();
3408 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3409
3410 int n = 0;
3411 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3412 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3413 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3414 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3415 n += (sz->_fields_bytes = sz->count_array(fields()));
3416 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3417 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3418 sz->_ro_bytes += n;
3419
3420 const ConstantPool* cp = constants();
3421 if (cp) {
3422 cp->collect_statistics(sz);
3423 }
3424
3425 const Annotations* anno = annotations();
3426 if (anno) {
3427 anno->collect_statistics(sz);
3428 }
3429
3430 const Array<Method*>* methods_array = methods();
3431 if (methods()) {
3432 for (int i = 0; i < methods_array->length(); i++) {
3433 Method* method = methods_array->at(i);
3434 if (method) {
3435 sz->_method_count ++;
3436 method->collect_statistics(sz);
3437 }
3438 }
3439 }
3440 }
3441 #endif // INCLUDE_SERVICES
3442
3443 // Verification
3444
3445 class VerifyFieldClosure: public BasicOopIterateClosure {
3446 protected:
3447 template <class T> void do_oop_work(T* p) {
3448 oop obj = RawAccess<>::oop_load(p);
3449 if (!oopDesc::is_oop_or_null(obj)) {
3450 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3451 Universe::print_on(tty);
3452 guarantee(false, "boom");
3453 }
3454 }
3455 public:
3456 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3457 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3458 };
3459
3460 void InstanceKlass::verify_on(outputStream* st) {
3461 #ifndef PRODUCT
3462 // Avoid redundant verifies, this really should be in product.
3463 if (_verify_count == Universe::verify_count()) return;
3464 _verify_count = Universe::verify_count();
3465 #endif
3466
3467 // Verify Klass
3468 Klass::verify_on(st);
3469
3470 // Verify that klass is present in ClassLoaderData
3471 guarantee(class_loader_data()->contains_klass(this),
3472 "this class isn't found in class loader data");
3473
3474 // Verify vtables
3475 if (is_linked()) {
3476 // $$$ This used to be done only for m/s collections. Doing it
3477 // always seemed a valid generalization. (DLD -- 6/00)
3478 vtable().verify(st);
3479 }
3480
3481 // Verify first subklass
3482 if (subklass() != NULL) {
3483 guarantee(subklass()->is_klass(), "should be klass");
3484 }
3485
3486 // Verify siblings
3487 Klass* super = this->super();
3488 Klass* sib = next_sibling();
3489 if (sib != NULL) {
3490 if (sib == this) {
3491 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3492 }
3493
3494 guarantee(sib->is_klass(), "should be klass");
3495 guarantee(sib->super() == super, "siblings should have same superklass");
3496 }
3497
3498 // Verify implementor fields
3499 Klass* im = implementor();
3500 if (im != NULL) {
3501 guarantee(is_interface(), "only interfaces should have implementor set");
3502 guarantee(im->is_klass(), "should be klass");
3503 guarantee(!im->is_interface() || im == this,
3504 "implementors cannot be interfaces");
3505 }
3506
3507 // Verify local interfaces
3508 if (local_interfaces()) {
3509 Array<Klass*>* local_interfaces = this->local_interfaces();
3510 for (int j = 0; j < local_interfaces->length(); j++) {
3511 Klass* e = local_interfaces->at(j);
3512 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3513 }
3514 }
3515
3516 // Verify transitive interfaces
3517 if (transitive_interfaces() != NULL) {
3518 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3519 for (int j = 0; j < transitive_interfaces->length(); j++) {
3520 Klass* e = transitive_interfaces->at(j);
3521 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3522 }
3523 }
3524
3525 // Verify methods
3526 if (methods() != NULL) {
3527 Array<Method*>* methods = this->methods();
3528 for (int j = 0; j < methods->length(); j++) {
3529 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3530 }
3531 for (int j = 0; j < methods->length() - 1; j++) {
3532 Method* m1 = methods->at(j);
3533 Method* m2 = methods->at(j + 1);
3534 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3535 }
3536 }
3537
3538 // Verify method ordering
3539 if (method_ordering() != NULL) {
3540 Array<int>* method_ordering = this->method_ordering();
3541 int length = method_ordering->length();
3542 if (JvmtiExport::can_maintain_original_method_order() ||
3543 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3544 guarantee(length == methods()->length(), "invalid method ordering length");
3545 jlong sum = 0;
3546 for (int j = 0; j < length; j++) {
3547 int original_index = method_ordering->at(j);
3548 guarantee(original_index >= 0, "invalid method ordering index");
3549 guarantee(original_index < length, "invalid method ordering index");
3550 sum += original_index;
3551 }
3552 // Verify sum of indices 0,1,...,length-1
3553 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3554 } else {
3555 guarantee(length == 0, "invalid method ordering length");
3556 }
3557 }
3558
3559 // Verify default methods
3560 if (default_methods() != NULL) {
3561 Array<Method*>* methods = this->default_methods();
3562 for (int j = 0; j < methods->length(); j++) {
3563 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3564 }
3565 for (int j = 0; j < methods->length() - 1; j++) {
3566 Method* m1 = methods->at(j);
3567 Method* m2 = methods->at(j + 1);
3568 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3569 }
3570 }
3571
3572 // Verify JNI static field identifiers
3573 if (jni_ids() != NULL) {
3574 jni_ids()->verify(this);
3575 }
3576
3577 // Verify other fields
3578 if (array_klasses() != NULL) {
3579 guarantee(array_klasses()->is_klass(), "should be klass");
3580 }
3581 if (constants() != NULL) {
3582 guarantee(constants()->is_constantPool(), "should be constant pool");
3583 }
3584 const Klass* host = host_klass();
3585 if (host != NULL) {
3586 guarantee(host->is_klass(), "should be klass");
3587 }
3588 }
3589
3590 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3591 Klass::oop_verify_on(obj, st);
3592 VerifyFieldClosure blk;
3593 obj->oop_iterate(&blk);
3594 }
3595
3596
3597 // JNIid class for jfieldIDs only
3598 // Note to reviewers:
3599 // These JNI functions are just moved over to column 1 and not changed
3600 // in the compressed oops workspace.
3601 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3602 _holder = holder;
3603 _offset = offset;
3604 _next = next;
3605 debug_only(_is_static_field_id = false;)
3606 }
3607
3608
3609 JNIid* JNIid::find(int offset) {
3610 JNIid* current = this;
3611 while (current != NULL) {
3612 if (current->offset() == offset) return current;
3613 current = current->next();
3614 }
3615 return NULL;
3616 }
3617
3618 void JNIid::deallocate(JNIid* current) {
3619 while (current != NULL) {
3620 JNIid* next = current->next();
3621 delete current;
3622 current = next;
3623 }
3624 }
3625
3626
3627 void JNIid::verify(Klass* holder) {
3628 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3629 int end_field_offset;
3630 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3631
3632 JNIid* current = this;
3633 while (current != NULL) {
3634 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3635 #ifdef ASSERT
3636 int o = current->offset();
3637 if (current->is_static_field_id()) {
3638 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3639 }
3640 #endif
3641 current = current->next();
3642 }
3643 }
3644
3645 #ifdef ASSERT
3646 void InstanceKlass::set_init_state(ClassState state) {
3647 bool good_state = is_shared() ? (_init_state <= state)
3648 : (_init_state < state);
3649 assert(good_state || state == allocated, "illegal state transition");
3650 _init_state = (u1)state;
3651 }
3652 #endif
3653
3654 #if INCLUDE_JVMTI
3655
3656 // RedefineClasses() support for previous versions
3657
3658 // Globally, there is at least one previous version of a class to walk
3659 // during class unloading, which is saved because old methods in the class
3660 // are still running. Otherwise the previous version list is cleaned up.
3661 bool InstanceKlass::_has_previous_versions = false;
3662
3663 // Returns true if there are previous versions of a class for class
3664 // unloading only. Also resets the flag to false. purge_previous_version
3665 // will set the flag to true if there are any left, i.e., if there's any
3666 // work to do for next time. This is to avoid the expensive code cache
3667 // walk in CLDG::do_unloading().
3668 bool InstanceKlass::has_previous_versions_and_reset() {
3669 bool ret = _has_previous_versions;
3670 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3671 ret ? "true" : "false");
3672 _has_previous_versions = false;
3673 return ret;
3674 }
3675
3676 // Purge previous versions before adding new previous versions of the class and
3677 // during class unloading.
3678 void InstanceKlass::purge_previous_version_list() {
3679 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3680 assert(has_been_redefined(), "Should only be called for main class");
3681
3682 // Quick exit.
3683 if (previous_versions() == NULL) {
3684 return;
3685 }
3686
3687 // This klass has previous versions so see what we can cleanup
3688 // while it is safe to do so.
3689
3690 int deleted_count = 0; // leave debugging breadcrumbs
3691 int live_count = 0;
3692 ClassLoaderData* loader_data = class_loader_data();
3693 assert(loader_data != NULL, "should never be null");
3694
3695 ResourceMark rm;
3696 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3697
3698 // previous versions are linked together through the InstanceKlass
3699 InstanceKlass* pv_node = previous_versions();
3700 InstanceKlass* last = this;
3701 int version = 0;
3702
3703 // check the previous versions list
3704 for (; pv_node != NULL; ) {
3705
3706 ConstantPool* pvcp = pv_node->constants();
3707 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3708
3709 if (!pvcp->on_stack()) {
3710 // If the constant pool isn't on stack, none of the methods
3711 // are executing. Unlink this previous_version.
3712 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3713 // so will be deallocated during the next phase of class unloading.
3714 log_trace(redefine, class, iklass, purge)
3715 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3716 // For debugging purposes.
3717 pv_node->set_is_scratch_class();
3718 // Unlink from previous version list.
3719 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3720 InstanceKlass* next = pv_node->previous_versions();
3721 pv_node->link_previous_versions(NULL); // point next to NULL
3722 last->link_previous_versions(next);
3723 // Add to the deallocate list after unlinking
3724 loader_data->add_to_deallocate_list(pv_node);
3725 pv_node = next;
3726 deleted_count++;
3727 version++;
3728 continue;
3729 } else {
3730 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3731 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3732 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3733 live_count++;
3734 // found a previous version for next time we do class unloading
3735 _has_previous_versions = true;
3736 }
3737
3738 // At least one method is live in this previous version.
3739 // Reset dead EMCP methods not to get breakpoints.
3740 // All methods are deallocated when all of the methods for this class are no
3741 // longer running.
3742 Array<Method*>* method_refs = pv_node->methods();
3743 if (method_refs != NULL) {
3744 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3745 for (int j = 0; j < method_refs->length(); j++) {
3746 Method* method = method_refs->at(j);
3747
3748 if (!method->on_stack()) {
3749 // no breakpoints for non-running methods
3750 if (method->is_running_emcp()) {
3751 method->set_running_emcp(false);
3752 }
3753 } else {
3754 assert (method->is_obsolete() || method->is_running_emcp(),
3755 "emcp method cannot run after emcp bit is cleared");
3756 log_trace(redefine, class, iklass, purge)
3757 ("purge: %s(%s): prev method @%d in version @%d is alive",
3758 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3759 }
3760 }
3761 }
3762 // next previous version
3763 last = pv_node;
3764 pv_node = pv_node->previous_versions();
3765 version++;
3766 }
3767 log_trace(redefine, class, iklass, purge)
3768 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3769 }
3770
3771 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3772 int emcp_method_count) {
3773 int obsolete_method_count = old_methods->length() - emcp_method_count;
3774
3775 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3776 _previous_versions != NULL) {
3777 // We have a mix of obsolete and EMCP methods so we have to
3778 // clear out any matching EMCP method entries the hard way.
3779 int local_count = 0;
3780 for (int i = 0; i < old_methods->length(); i++) {
3781 Method* old_method = old_methods->at(i);
3782 if (old_method->is_obsolete()) {
3783 // only obsolete methods are interesting
3784 Symbol* m_name = old_method->name();
3785 Symbol* m_signature = old_method->signature();
3786
3787 // previous versions are linked together through the InstanceKlass
3788 int j = 0;
3789 for (InstanceKlass* prev_version = _previous_versions;
3790 prev_version != NULL;
3791 prev_version = prev_version->previous_versions(), j++) {
3792
3793 Array<Method*>* method_refs = prev_version->methods();
3794 for (int k = 0; k < method_refs->length(); k++) {
3795 Method* method = method_refs->at(k);
3796
3797 if (!method->is_obsolete() &&
3798 method->name() == m_name &&
3799 method->signature() == m_signature) {
3800 // The current RedefineClasses() call has made all EMCP
3801 // versions of this method obsolete so mark it as obsolete
3802 log_trace(redefine, class, iklass, add)
3803 ("%s(%s): flush obsolete method @%d in version @%d",
3804 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3805
3806 method->set_is_obsolete();
3807 break;
3808 }
3809 }
3810
3811 // The previous loop may not find a matching EMCP method, but
3812 // that doesn't mean that we can optimize and not go any
3813 // further back in the PreviousVersion generations. The EMCP
3814 // method for this generation could have already been made obsolete,
3815 // but there still may be an older EMCP method that has not
3816 // been made obsolete.
3817 }
3818
3819 if (++local_count >= obsolete_method_count) {
3820 // no more obsolete methods so bail out now
3821 break;
3822 }
3823 }
3824 }
3825 }
3826 }
3827
3828 // Save the scratch_class as the previous version if any of the methods are running.
3829 // The previous_versions are used to set breakpoints in EMCP methods and they are
3830 // also used to clean MethodData links to redefined methods that are no longer running.
3831 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3832 int emcp_method_count) {
3833 assert(Thread::current()->is_VM_thread(),
3834 "only VMThread can add previous versions");
3835
3836 ResourceMark rm;
3837 log_trace(redefine, class, iklass, add)
3838 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3839
3840 // Clean out old previous versions for this class
3841 purge_previous_version_list();
3842
3843 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3844 // a previous redefinition may be made obsolete by this redefinition.
3845 Array<Method*>* old_methods = scratch_class->methods();
3846 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3847
3848 // If the constant pool for this previous version of the class
3849 // is not marked as being on the stack, then none of the methods
3850 // in this previous version of the class are on the stack so
3851 // we don't need to add this as a previous version.
3852 ConstantPool* cp_ref = scratch_class->constants();
3853 if (!cp_ref->on_stack()) {
3854 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3855 // For debugging purposes.
3856 scratch_class->set_is_scratch_class();
3857 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3858 return;
3859 }
3860
3861 if (emcp_method_count != 0) {
3862 // At least one method is still running, check for EMCP methods
3863 for (int i = 0; i < old_methods->length(); i++) {
3864 Method* old_method = old_methods->at(i);
3865 if (!old_method->is_obsolete() && old_method->on_stack()) {
3866 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3867 // we can add breakpoints for it.
3868
3869 // We set the method->on_stack bit during safepoints for class redefinition
3870 // and use this bit to set the is_running_emcp bit.
3871 // After the safepoint, the on_stack bit is cleared and the running emcp
3872 // method may exit. If so, we would set a breakpoint in a method that
3873 // is never reached, but this won't be noticeable to the programmer.
3874 old_method->set_running_emcp(true);
3875 log_trace(redefine, class, iklass, add)
3876 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3877 } else if (!old_method->is_obsolete()) {
3878 log_trace(redefine, class, iklass, add)
3879 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3880 }
3881 }
3882 }
3883
3884 // Add previous version if any methods are still running.
3885 // Set has_previous_version flag for processing during class unloading.
3886 _has_previous_versions = true;
3887 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3888 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3889 scratch_class->link_previous_versions(previous_versions());
3890 link_previous_versions(scratch_class);
3891 } // end add_previous_version()
3892
3893 #endif // INCLUDE_JVMTI
3894
3895 Method* InstanceKlass::method_with_idnum(int idnum) {
3896 Method* m = NULL;
3897 if (idnum < methods()->length()) {
3898 m = methods()->at(idnum);
3899 }
3900 if (m == NULL || m->method_idnum() != idnum) {
3901 for (int index = 0; index < methods()->length(); ++index) {
3902 m = methods()->at(index);
3903 if (m->method_idnum() == idnum) {
3904 return m;
3905 }
3906 }
3907 // None found, return null for the caller to handle.
3908 return NULL;
3909 }
3910 return m;
3911 }
3912
3913
3914 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3915 if (idnum >= methods()->length()) {
3916 return NULL;
3917 }
3918 Method* m = methods()->at(idnum);
3919 if (m != NULL && m->orig_method_idnum() == idnum) {
3920 return m;
3921 }
3922 // Obsolete method idnum does not match the original idnum
3923 for (int index = 0; index < methods()->length(); ++index) {
3924 m = methods()->at(index);
3925 if (m->orig_method_idnum() == idnum) {
3926 return m;
3927 }
3928 }
3929 // None found, return null for the caller to handle.
3930 return NULL;
3931 }
3932
3933
3934 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3935 InstanceKlass* holder = get_klass_version(version);
3936 if (holder == NULL) {
3937 return NULL; // The version of klass is gone, no method is found
3938 }
3939 Method* method = holder->method_with_orig_idnum(idnum);
3940 return method;
3941 }
3942
3943 #if INCLUDE_JVMTI
3944 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3945 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3946 // Ignore the archived class stream data
3947 return NULL;
3948 } else {
3949 return _cached_class_file;
3950 }
3951 }
3952
3953 jint InstanceKlass::get_cached_class_file_len() {
3954 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3955 }
3956
3957 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3958 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3959 }
3960
3961 #if INCLUDE_CDS
3962 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3963 if (DumpSharedSpaces) {
3964 return _cached_class_file;
3965 } else {
3966 assert(this->is_shared(), "class should be shared");
3967 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3968 return _cached_class_file;
3969 } else {
3970 return NULL;
3971 }
3972 }
3973 }
3974 #endif
3975 #endif