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 const char* desc = "Could not initialize class ";
938 const char* className = external_name();
939 size_t msglen = strlen(desc) + strlen(className) + 1;
940 char* message = NEW_RESOURCE_ARRAY_IN_THREAD_RETURN_NULL(THREAD, char, msglen);
941 if (NULL == message) {
942 // Out of memory: can't create detailed error message
943 message = const_cast<char*>(className);
944 } else {
945 jio_snprintf(message, msglen, "%s%s", desc, className);
946 }
947 Exceptions::_throw_msg_cause(THREAD_AND_LOCATION,
948 vmSymbols::java_lang_NoClassDefFoundError(),
949 message,
950 class_loader_data()->query_init_exception(java_mirror_handle(), THREAD));
951 return;
952 }
953
954 // Step 6
955 set_init_state(being_initialized);
956 set_init_thread(self);
957 }
958
959 // Step 7
960 // Next, if C is a class rather than an interface, initialize it's super class and super
961 // interfaces.
962 if (!is_interface()) {
963 Klass* super_klass = super();
964 if (super_klass != NULL && super_klass->should_be_initialized()) {
965 super_klass->initialize(THREAD);
966 }
967 // If C implements any interface that declares a non-static, concrete method,
968 // the initialization of C triggers initialization of its super interfaces.
969 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
970 // having a superinterface that declares, non-static, concrete methods
971 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
972 initialize_super_interfaces(THREAD);
973 }
974
975 // If any exceptions, complete abruptly, throwing the same exception as above.
976 if (HAS_PENDING_EXCEPTION) {
977 Handle e(THREAD, PENDING_EXCEPTION);
978 CLEAR_PENDING_EXCEPTION;
979 {
980 EXCEPTION_MARK;
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 set_initialization_state_and_notify(initialization_error, THREAD);
1028 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1029 // JVMTI has already reported the pending exception
1030 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1031 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1032 }
1033 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1034 if (!e->is_a(SystemDictionary::Error_klass())) {
1035 // Wrap anything but errors into ExceptionInInitializerError.
1036 JavaCallArguments args(e);
1037 Handle h_loader(THREAD, NULL);
1038 Handle h_prot(THREAD, NULL);
1039 e = Exceptions::new_exception(THREAD,
1040 vmSymbols::java_lang_ExceptionInInitializerError(),
1041 vmSymbols::throwable_void_signature(),
1042 &args, h_loader, h_prot);
1043 }
1044 // Store the exception that originally caused <clinit> to fail so
1045 // it can be chained into potential later NoClassDefFoundErrors.
1046 class_loader_data()->record_init_exception(java_mirror_handle(), e, THREAD);
1047 THROW_OOP(e());
1048 }
1049 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1050 }
1051
1052
1053 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1054 Handle h_init_lock(THREAD, init_lock());
1055 if (h_init_lock() != NULL) {
1056 ObjectLocker ol(h_init_lock, THREAD);
1057 set_init_state(state);
1058 fence_and_clear_init_lock();
1059 ol.notify_all(CHECK);
1060 } else {
1061 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1062 set_init_state(state);
1063 }
1064 }
1065
1066 // The embedded _implementor field can only record one implementor.
1067 // When there are more than one implementors, the _implementor field
1068 // is set to the interface Klass* itself. Following are the possible
1069 // values for the _implementor field:
1070 // NULL - no implementor
1071 // implementor Klass* - one implementor
1072 // self - more than one implementor
1073 //
1074 // The _implementor field only exists for interfaces.
1075 void InstanceKlass::add_implementor(Klass* k) {
1076 assert(Compile_lock->owned_by_self(), "");
1077 assert(is_interface(), "not interface");
1078 // Filter out my subinterfaces.
1079 // (Note: Interfaces are never on the subklass list.)
1080 if (InstanceKlass::cast(k)->is_interface()) return;
1081
1082 // Filter out subclasses whose supers already implement me.
1083 // (Note: CHA must walk subclasses of direct implementors
1084 // in order to locate indirect implementors.)
1085 Klass* sk = k->super();
1086 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1087 // We only need to check one immediate superclass, since the
1088 // implements_interface query looks at transitive_interfaces.
1089 // Any supers of the super have the same (or fewer) transitive_interfaces.
1090 return;
1091
1092 Klass* ik = implementor();
1093 if (ik == NULL) {
1094 set_implementor(k);
1095 } else if (ik != this) {
1096 // There is already an implementor. Use itself as an indicator of
1097 // more than one implementors.
1098 set_implementor(this);
1099 }
1100
1101 // The implementor also implements the transitive_interfaces
1102 for (int index = 0; index < local_interfaces()->length(); index++) {
1103 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1104 }
1105 }
1106
1107 void InstanceKlass::init_implementor() {
1108 if (is_interface()) {
1109 set_implementor(NULL);
1110 }
1111 }
1112
1113
1114 void InstanceKlass::process_interfaces(Thread *thread) {
1115 // link this class into the implementors list of every interface it implements
1116 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1117 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1118 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1119 assert(interf->is_interface(), "expected interface");
1120 interf->add_implementor(this);
1121 }
1122 }
1123
1124 bool InstanceKlass::can_be_primary_super_slow() const {
1125 if (is_interface())
1126 return false;
1127 else
1128 return Klass::can_be_primary_super_slow();
1129 }
1130
1131 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1132 Array<Klass*>* transitive_interfaces) {
1133 // The secondaries are the implemented interfaces.
1134 Array<Klass*>* interfaces = transitive_interfaces;
1135 int num_secondaries = num_extra_slots + interfaces->length();
1136 if (num_secondaries == 0) {
1137 // Must share this for correct bootstrapping!
1138 set_secondary_supers(Universe::the_empty_klass_array());
1139 return NULL;
1140 } else if (num_extra_slots == 0) {
1141 // The secondary super list is exactly the same as the transitive interfaces.
1142 // Redefine classes has to be careful not to delete this!
1143 set_secondary_supers(interfaces);
1144 return NULL;
1145 } else {
1146 // Copy transitive interfaces to a temporary growable array to be constructed
1147 // into the secondary super list with extra slots.
1148 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1149 for (int i = 0; i < interfaces->length(); i++) {
1150 secondaries->push(interfaces->at(i));
1151 }
1152 return secondaries;
1153 }
1154 }
1155
1156 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1157 if (k->is_interface()) {
1158 return implements_interface(k);
1159 } else {
1160 return Klass::compute_is_subtype_of(k);
1161 }
1162 }
1163
1164 bool InstanceKlass::implements_interface(Klass* k) const {
1165 if (this == k) return true;
1166 assert(k->is_interface(), "should be an interface class");
1167 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1168 if (transitive_interfaces()->at(i) == k) {
1169 return true;
1170 }
1171 }
1172 return false;
1173 }
1174
1175 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1176 // Verify direct super interface
1177 if (this == k) return true;
1178 assert(k->is_interface(), "should be an interface class");
1179 for (int i = 0; i < local_interfaces()->length(); i++) {
1180 if (local_interfaces()->at(i) == k) {
1181 return true;
1182 }
1183 }
1184 return false;
1185 }
1186
1187 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1188 if (length < 0) {
1189 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1190 }
1191 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1192 report_java_out_of_memory("Requested array size exceeds VM limit");
1193 JvmtiExport::post_array_size_exhausted();
1194 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1195 }
1196 int size = objArrayOopDesc::object_size(length);
1197 Klass* ak = array_klass(n, CHECK_NULL);
1198 objArrayOop o =
1199 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1200 return o;
1201 }
1202
1203 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1204 if (TraceFinalizerRegistration) {
1205 tty->print("Registered ");
1206 i->print_value_on(tty);
1207 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1208 }
1209 instanceHandle h_i(THREAD, i);
1210 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1211 JavaValue result(T_VOID);
1212 JavaCallArguments args(h_i);
1213 methodHandle mh (THREAD, Universe::finalizer_register_method());
1214 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1215 return h_i();
1216 }
1217
1218 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1219 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1220 int size = size_helper(); // Query before forming handle.
1221
1222 instanceOop i;
1223
1224 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1225 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1226 i = register_finalizer(i, CHECK_NULL);
1227 }
1228 return i;
1229 }
1230
1231 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1232 return instanceHandle(THREAD, allocate_instance(THREAD));
1233 }
1234
1235 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1236 if (is_interface() || is_abstract()) {
1237 ResourceMark rm(THREAD);
1238 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1239 : vmSymbols::java_lang_InstantiationException(), external_name());
1240 }
1241 if (this == SystemDictionary::Class_klass()) {
1242 ResourceMark rm(THREAD);
1243 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1244 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1245 }
1246 }
1247
1248 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1249 // Need load-acquire for lock-free read
1250 if (array_klasses_acquire() == NULL) {
1251 if (or_null) return NULL;
1252
1253 ResourceMark rm;
1254 JavaThread *jt = (JavaThread *)THREAD;
1255 {
1256 // Atomic creation of array_klasses
1257 MutexLocker mc(Compile_lock, THREAD); // for vtables
1258 MutexLocker ma(MultiArray_lock, THREAD);
1259
1260 // Check if update has already taken place
1261 if (array_klasses() == NULL) {
1262 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1263 // use 'release' to pair with lock-free load
1264 release_set_array_klasses(k);
1265 }
1266 }
1267 }
1268 // _this will always be set at this point
1269 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1270 if (or_null) {
1271 return oak->array_klass_or_null(n);
1272 }
1273 return oak->array_klass(n, THREAD);
1274 }
1275
1276 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1277 return array_klass_impl(or_null, 1, THREAD);
1278 }
1279
1280 static int call_class_initializer_counter = 0; // for debugging
1281
1282 Method* InstanceKlass::class_initializer() const {
1283 Method* clinit = find_method(
1284 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1285 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1286 return clinit;
1287 }
1288 return NULL;
1289 }
1290
1291 void InstanceKlass::call_class_initializer(TRAPS) {
1292 if (ReplayCompiles &&
1293 (ReplaySuppressInitializers == 1 ||
1294 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1295 // Hide the existence of the initializer for the purpose of replaying the compile
1296 return;
1297 }
1298
1299 methodHandle h_method(THREAD, class_initializer());
1300 assert(!is_initialized(), "we cannot initialize twice");
1301 LogTarget(Info, class, init) lt;
1302 if (lt.is_enabled()) {
1303 ResourceMark rm;
1304 LogStream ls(lt);
1305 ls.print("%d Initializing ", call_class_initializer_counter++);
1306 name()->print_value_on(&ls);
1307 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1308 }
1309 if (h_method() != NULL) {
1310 JavaCallArguments args; // No arguments
1311 JavaValue result(T_VOID);
1312 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1313 }
1314 }
1315
1316
1317 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1318 InterpreterOopMap* entry_for) {
1319 // Lazily create the _oop_map_cache at first request
1320 // Lock-free access requires load_acquire.
1321 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1322 if (oop_map_cache == NULL) {
1323 MutexLocker x(OopMapCacheAlloc_lock);
1324 // Check if _oop_map_cache was allocated while we were waiting for this lock
1325 if ((oop_map_cache = _oop_map_cache) == NULL) {
1326 oop_map_cache = new OopMapCache();
1327 // Ensure _oop_map_cache is stable, since it is examined without a lock
1328 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1329 }
1330 }
1331 // _oop_map_cache is constant after init; lookup below does its own locking.
1332 oop_map_cache->lookup(method, bci, entry_for);
1333 }
1334
1335
1336 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1337 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1338 Symbol* f_name = fs.name();
1339 Symbol* f_sig = fs.signature();
1340 if (f_name == name && f_sig == sig) {
1341 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1342 return true;
1343 }
1344 }
1345 return false;
1346 }
1347
1348
1349 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1350 const int n = local_interfaces()->length();
1351 for (int i = 0; i < n; i++) {
1352 Klass* intf1 = local_interfaces()->at(i);
1353 assert(intf1->is_interface(), "just checking type");
1354 // search for field in current interface
1355 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1356 assert(fd->is_static(), "interface field must be static");
1357 return intf1;
1358 }
1359 // search for field in direct superinterfaces
1360 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1361 if (intf2 != NULL) return intf2;
1362 }
1363 // otherwise field lookup fails
1364 return NULL;
1365 }
1366
1367
1368 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1369 // search order according to newest JVM spec (5.4.3.2, p.167).
1370 // 1) search for field in current klass
1371 if (find_local_field(name, sig, fd)) {
1372 return const_cast<InstanceKlass*>(this);
1373 }
1374 // 2) search for field recursively in direct superinterfaces
1375 { Klass* intf = find_interface_field(name, sig, fd);
1376 if (intf != NULL) return intf;
1377 }
1378 // 3) apply field lookup recursively if superclass exists
1379 { Klass* supr = super();
1380 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1381 }
1382 // 4) otherwise field lookup fails
1383 return NULL;
1384 }
1385
1386
1387 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1388 // search order according to newest JVM spec (5.4.3.2, p.167).
1389 // 1) search for field in current klass
1390 if (find_local_field(name, sig, fd)) {
1391 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1392 }
1393 // 2) search for field recursively in direct superinterfaces
1394 if (is_static) {
1395 Klass* intf = find_interface_field(name, sig, fd);
1396 if (intf != NULL) return intf;
1397 }
1398 // 3) apply field lookup recursively if superclass exists
1399 { Klass* supr = super();
1400 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1401 }
1402 // 4) otherwise field lookup fails
1403 return NULL;
1404 }
1405
1406
1407 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1408 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1409 if (fs.offset() == offset) {
1410 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1411 if (fd->is_static() == is_static) return true;
1412 }
1413 }
1414 return false;
1415 }
1416
1417
1418 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1419 Klass* klass = const_cast<InstanceKlass*>(this);
1420 while (klass != NULL) {
1421 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1422 return true;
1423 }
1424 klass = klass->super();
1425 }
1426 return false;
1427 }
1428
1429
1430 void InstanceKlass::methods_do(void f(Method* method)) {
1431 // Methods aren't stable until they are loaded. This can be read outside
1432 // a lock through the ClassLoaderData for profiling
1433 if (!is_loaded()) {
1434 return;
1435 }
1436
1437 int len = methods()->length();
1438 for (int index = 0; index < len; index++) {
1439 Method* m = methods()->at(index);
1440 assert(m->is_method(), "must be method");
1441 f(m);
1442 }
1443 }
1444
1445
1446 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1447 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1448 if (fs.access_flags().is_static()) {
1449 fieldDescriptor& fd = fs.field_descriptor();
1450 cl->do_field(&fd);
1451 }
1452 }
1453 }
1454
1455
1456 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1457 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1458 if (fs.access_flags().is_static()) {
1459 fieldDescriptor& fd = fs.field_descriptor();
1460 f(&fd, mirror, CHECK);
1461 }
1462 }
1463 }
1464
1465
1466 static int compare_fields_by_offset(int* a, int* b) {
1467 return a[0] - b[0];
1468 }
1469
1470 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1471 InstanceKlass* super = superklass();
1472 if (super != NULL) {
1473 super->do_nonstatic_fields(cl);
1474 }
1475 fieldDescriptor fd;
1476 int length = java_fields_count();
1477 // In DebugInfo nonstatic fields are sorted by offset.
1478 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1479 int j = 0;
1480 for (int i = 0; i < length; i += 1) {
1481 fd.reinitialize(this, i);
1482 if (!fd.is_static()) {
1483 fields_sorted[j + 0] = fd.offset();
1484 fields_sorted[j + 1] = i;
1485 j += 2;
1486 }
1487 }
1488 if (j > 0) {
1489 length = j;
1490 // _sort_Fn is defined in growableArray.hpp.
1491 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1492 for (int i = 0; i < length; i += 2) {
1493 fd.reinitialize(this, fields_sorted[i + 1]);
1494 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1495 cl->do_field(&fd);
1496 }
1497 }
1498 FREE_C_HEAP_ARRAY(int, fields_sorted);
1499 }
1500
1501
1502 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1503 if (array_klasses() != NULL)
1504 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1505 }
1506
1507 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1508 if (array_klasses() != NULL)
1509 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1510 }
1511
1512 #ifdef ASSERT
1513 static int linear_search(const Array<Method*>* methods,
1514 const Symbol* name,
1515 const Symbol* signature) {
1516 const int len = methods->length();
1517 for (int index = 0; index < len; index++) {
1518 const Method* const m = methods->at(index);
1519 assert(m->is_method(), "must be method");
1520 if (m->signature() == signature && m->name() == name) {
1521 return index;
1522 }
1523 }
1524 return -1;
1525 }
1526 #endif
1527
1528 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1529 int len = methods->length();
1530 // methods are sorted, so do binary search
1531 int l = 0;
1532 int h = len - 1;
1533 while (l <= h) {
1534 int mid = (l + h) >> 1;
1535 Method* m = methods->at(mid);
1536 assert(m->is_method(), "must be method");
1537 int res = m->name()->fast_compare(name);
1538 if (res == 0) {
1539 return mid;
1540 } else if (res < 0) {
1541 l = mid + 1;
1542 } else {
1543 h = mid - 1;
1544 }
1545 }
1546 return -1;
1547 }
1548
1549 // find_method looks up the name/signature in the local methods array
1550 Method* InstanceKlass::find_method(const Symbol* name,
1551 const Symbol* signature) const {
1552 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1553 }
1554
1555 Method* InstanceKlass::find_method_impl(const Symbol* name,
1556 const Symbol* signature,
1557 OverpassLookupMode overpass_mode,
1558 StaticLookupMode static_mode,
1559 PrivateLookupMode private_mode) const {
1560 return InstanceKlass::find_method_impl(methods(),
1561 name,
1562 signature,
1563 overpass_mode,
1564 static_mode,
1565 private_mode);
1566 }
1567
1568 // find_instance_method looks up the name/signature in the local methods array
1569 // and skips over static methods
1570 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1571 const Symbol* name,
1572 const Symbol* signature,
1573 PrivateLookupMode private_mode) {
1574 Method* const meth = InstanceKlass::find_method_impl(methods,
1575 name,
1576 signature,
1577 find_overpass,
1578 skip_static,
1579 private_mode);
1580 assert(((meth == NULL) || !meth->is_static()),
1581 "find_instance_method should have skipped statics");
1582 return meth;
1583 }
1584
1585 // find_instance_method looks up the name/signature in the local methods array
1586 // and skips over static methods
1587 Method* InstanceKlass::find_instance_method(const Symbol* name,
1588 const Symbol* signature,
1589 PrivateLookupMode private_mode) const {
1590 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1591 }
1592
1593 // Find looks up the name/signature in the local methods array
1594 // and filters on the overpass, static and private flags
1595 // This returns the first one found
1596 // note that the local methods array can have up to one overpass, one static
1597 // and one instance (private or not) with the same name/signature
1598 Method* InstanceKlass::find_local_method(const Symbol* name,
1599 const Symbol* signature,
1600 OverpassLookupMode overpass_mode,
1601 StaticLookupMode static_mode,
1602 PrivateLookupMode private_mode) const {
1603 return InstanceKlass::find_method_impl(methods(),
1604 name,
1605 signature,
1606 overpass_mode,
1607 static_mode,
1608 private_mode);
1609 }
1610
1611 // Find looks up the name/signature in the local methods array
1612 // and filters on the overpass, static and private flags
1613 // This returns the first one found
1614 // note that the local methods array can have up to one overpass, one static
1615 // and one instance (private or not) with the same name/signature
1616 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1617 const Symbol* name,
1618 const Symbol* signature,
1619 OverpassLookupMode overpass_mode,
1620 StaticLookupMode static_mode,
1621 PrivateLookupMode private_mode) {
1622 return InstanceKlass::find_method_impl(methods,
1623 name,
1624 signature,
1625 overpass_mode,
1626 static_mode,
1627 private_mode);
1628 }
1629
1630 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1631 const Symbol* name,
1632 const Symbol* signature) {
1633 return InstanceKlass::find_method_impl(methods,
1634 name,
1635 signature,
1636 find_overpass,
1637 find_static,
1638 find_private);
1639 }
1640
1641 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1642 const Symbol* name,
1643 const Symbol* signature,
1644 OverpassLookupMode overpass_mode,
1645 StaticLookupMode static_mode,
1646 PrivateLookupMode private_mode) {
1647 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1648 return hit >= 0 ? methods->at(hit): NULL;
1649 }
1650
1651 // true if method matches signature and conforms to skipping_X conditions.
1652 static bool method_matches(const Method* m,
1653 const Symbol* signature,
1654 bool skipping_overpass,
1655 bool skipping_static,
1656 bool skipping_private) {
1657 return ((m->signature() == signature) &&
1658 (!skipping_overpass || !m->is_overpass()) &&
1659 (!skipping_static || !m->is_static()) &&
1660 (!skipping_private || !m->is_private()));
1661 }
1662
1663 // Used directly for default_methods to find the index into the
1664 // default_vtable_indices, and indirectly by find_method
1665 // find_method_index looks in the local methods array to return the index
1666 // of the matching name/signature. If, overpass methods are being ignored,
1667 // the search continues to find a potential non-overpass match. This capability
1668 // is important during method resolution to prefer a static method, for example,
1669 // over an overpass method.
1670 // There is the possibility in any _method's array to have the same name/signature
1671 // for a static method, an overpass method and a local instance method
1672 // To correctly catch a given method, the search criteria may need
1673 // to explicitly skip the other two. For local instance methods, it
1674 // is often necessary to skip private methods
1675 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1676 const Symbol* name,
1677 const Symbol* signature,
1678 OverpassLookupMode overpass_mode,
1679 StaticLookupMode static_mode,
1680 PrivateLookupMode private_mode) {
1681 const bool skipping_overpass = (overpass_mode == skip_overpass);
1682 const bool skipping_static = (static_mode == skip_static);
1683 const bool skipping_private = (private_mode == skip_private);
1684 const int hit = binary_search(methods, name);
1685 if (hit != -1) {
1686 const Method* const m = methods->at(hit);
1687
1688 // Do linear search to find matching signature. First, quick check
1689 // for common case, ignoring overpasses if requested.
1690 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1691 return hit;
1692 }
1693
1694 // search downwards through overloaded methods
1695 int i;
1696 for (i = hit - 1; i >= 0; --i) {
1697 const Method* const m = methods->at(i);
1698 assert(m->is_method(), "must be method");
1699 if (m->name() != name) {
1700 break;
1701 }
1702 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1703 return i;
1704 }
1705 }
1706 // search upwards
1707 for (i = hit + 1; i < methods->length(); ++i) {
1708 const Method* const m = methods->at(i);
1709 assert(m->is_method(), "must be method");
1710 if (m->name() != name) {
1711 break;
1712 }
1713 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1714 return i;
1715 }
1716 }
1717 // not found
1718 #ifdef ASSERT
1719 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1720 linear_search(methods, name, signature);
1721 assert(-1 == index, "binary search should have found entry %d", index);
1722 #endif
1723 }
1724 return -1;
1725 }
1726
1727 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1728 return find_method_by_name(methods(), name, end);
1729 }
1730
1731 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1732 const Symbol* name,
1733 int* end_ptr) {
1734 assert(end_ptr != NULL, "just checking");
1735 int start = binary_search(methods, name);
1736 int end = start + 1;
1737 if (start != -1) {
1738 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1739 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1740 *end_ptr = end;
1741 return start;
1742 }
1743 return -1;
1744 }
1745
1746 // uncached_lookup_method searches both the local class methods array and all
1747 // superclasses methods arrays, skipping any overpass methods in superclasses,
1748 // and possibly skipping private methods.
1749 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1750 const Symbol* signature,
1751 OverpassLookupMode overpass_mode,
1752 PrivateLookupMode private_mode) const {
1753 OverpassLookupMode overpass_local_mode = overpass_mode;
1754 const Klass* klass = this;
1755 while (klass != NULL) {
1756 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1757 signature,
1758 overpass_local_mode,
1759 find_static,
1760 private_mode);
1761 if (method != NULL) {
1762 return method;
1763 }
1764 klass = klass->super();
1765 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1766 }
1767 return NULL;
1768 }
1769
1770 #ifdef ASSERT
1771 // search through class hierarchy and return true if this class or
1772 // one of the superclasses was redefined
1773 bool InstanceKlass::has_redefined_this_or_super() const {
1774 const Klass* klass = this;
1775 while (klass != NULL) {
1776 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1777 return true;
1778 }
1779 klass = klass->super();
1780 }
1781 return false;
1782 }
1783 #endif
1784
1785 // lookup a method in the default methods list then in all transitive interfaces
1786 // Do NOT return private or static methods
1787 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1788 Symbol* signature) const {
1789 Method* m = NULL;
1790 if (default_methods() != NULL) {
1791 m = find_method(default_methods(), name, signature);
1792 }
1793 // Look up interfaces
1794 if (m == NULL) {
1795 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1796 }
1797 return m;
1798 }
1799
1800 // lookup a method in all the interfaces that this class implements
1801 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1802 // They should only be found in the initial InterfaceMethodRef
1803 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1804 Symbol* signature,
1805 DefaultsLookupMode defaults_mode) const {
1806 Array<Klass*>* all_ifs = transitive_interfaces();
1807 int num_ifs = all_ifs->length();
1808 InstanceKlass *ik = NULL;
1809 for (int i = 0; i < num_ifs; i++) {
1810 ik = InstanceKlass::cast(all_ifs->at(i));
1811 Method* m = ik->lookup_method(name, signature);
1812 if (m != NULL && m->is_public() && !m->is_static() &&
1813 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1814 return m;
1815 }
1816 }
1817 return NULL;
1818 }
1819
1820 /* jni_id_for_impl for jfieldIds only */
1821 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1822 MutexLocker ml(JfieldIdCreation_lock);
1823 // Retry lookup after we got the lock
1824 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1825 if (probe == NULL) {
1826 // Slow case, allocate new static field identifier
1827 probe = new JNIid(this, offset, jni_ids());
1828 set_jni_ids(probe);
1829 }
1830 return probe;
1831 }
1832
1833
1834 /* jni_id_for for jfieldIds only */
1835 JNIid* InstanceKlass::jni_id_for(int offset) {
1836 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1837 if (probe == NULL) {
1838 probe = jni_id_for_impl(offset);
1839 }
1840 return probe;
1841 }
1842
1843 u2 InstanceKlass::enclosing_method_data(int offset) const {
1844 const Array<jushort>* const inner_class_list = inner_classes();
1845 if (inner_class_list == NULL) {
1846 return 0;
1847 }
1848 const int length = inner_class_list->length();
1849 if (length % inner_class_next_offset == 0) {
1850 return 0;
1851 }
1852 const int index = length - enclosing_method_attribute_size;
1853 assert(offset < enclosing_method_attribute_size, "invalid offset");
1854 return inner_class_list->at(index + offset);
1855 }
1856
1857 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1858 u2 method_index) {
1859 Array<jushort>* inner_class_list = inner_classes();
1860 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1861 int length = inner_class_list->length();
1862 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1863 int index = length - enclosing_method_attribute_size;
1864 inner_class_list->at_put(
1865 index + enclosing_method_class_index_offset, class_index);
1866 inner_class_list->at_put(
1867 index + enclosing_method_method_index_offset, method_index);
1868 }
1869 }
1870
1871 // Lookup or create a jmethodID.
1872 // This code is called by the VMThread and JavaThreads so the
1873 // locking has to be done very carefully to avoid deadlocks
1874 // and/or other cache consistency problems.
1875 //
1876 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1877 size_t idnum = (size_t)method_h->method_idnum();
1878 jmethodID* jmeths = methods_jmethod_ids_acquire();
1879 size_t length = 0;
1880 jmethodID id = NULL;
1881
1882 // We use a double-check locking idiom here because this cache is
1883 // performance sensitive. In the normal system, this cache only
1884 // transitions from NULL to non-NULL which is safe because we use
1885 // release_set_methods_jmethod_ids() to advertise the new cache.
1886 // A partially constructed cache should never be seen by a racing
1887 // thread. We also use release_store() to save a new jmethodID
1888 // in the cache so a partially constructed jmethodID should never be
1889 // seen either. Cache reads of existing jmethodIDs proceed without a
1890 // lock, but cache writes of a new jmethodID requires uniqueness and
1891 // creation of the cache itself requires no leaks so a lock is
1892 // generally acquired in those two cases.
1893 //
1894 // If the RedefineClasses() API has been used, then this cache can
1895 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1896 // Cache creation requires no leaks and we require safety between all
1897 // cache accesses and freeing of the old cache so a lock is generally
1898 // acquired when the RedefineClasses() API has been used.
1899
1900 if (jmeths != NULL) {
1901 // the cache already exists
1902 if (!idnum_can_increment()) {
1903 // the cache can't grow so we can just get the current values
1904 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1905 } else {
1906 // cache can grow so we have to be more careful
1907 if (Threads::number_of_threads() == 0 ||
1908 SafepointSynchronize::is_at_safepoint()) {
1909 // we're single threaded or at a safepoint - no locking needed
1910 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1911 } else {
1912 MutexLocker ml(JmethodIdCreation_lock);
1913 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1914 }
1915 }
1916 }
1917 // implied else:
1918 // we need to allocate a cache so default length and id values are good
1919
1920 if (jmeths == NULL || // no cache yet
1921 length <= idnum || // cache is too short
1922 id == NULL) { // cache doesn't contain entry
1923
1924 // This function can be called by the VMThread so we have to do all
1925 // things that might block on a safepoint before grabbing the lock.
1926 // Otherwise, we can deadlock with the VMThread or have a cache
1927 // consistency issue. These vars keep track of what we might have
1928 // to free after the lock is dropped.
1929 jmethodID to_dealloc_id = NULL;
1930 jmethodID* to_dealloc_jmeths = NULL;
1931
1932 // may not allocate new_jmeths or use it if we allocate it
1933 jmethodID* new_jmeths = NULL;
1934 if (length <= idnum) {
1935 // allocate a new cache that might be used
1936 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1937 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1938 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1939 // cache size is stored in element[0], other elements offset by one
1940 new_jmeths[0] = (jmethodID)size;
1941 }
1942
1943 // allocate a new jmethodID that might be used
1944 jmethodID new_id = NULL;
1945 if (method_h->is_old() && !method_h->is_obsolete()) {
1946 // The method passed in is old (but not obsolete), we need to use the current version
1947 Method* current_method = method_with_idnum((int)idnum);
1948 assert(current_method != NULL, "old and but not obsolete, so should exist");
1949 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1950 } else {
1951 // It is the current version of the method or an obsolete method,
1952 // use the version passed in
1953 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1954 }
1955
1956 if (Threads::number_of_threads() == 0 ||
1957 SafepointSynchronize::is_at_safepoint()) {
1958 // we're single threaded or at a safepoint - no locking needed
1959 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1960 &to_dealloc_id, &to_dealloc_jmeths);
1961 } else {
1962 MutexLocker ml(JmethodIdCreation_lock);
1963 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1964 &to_dealloc_id, &to_dealloc_jmeths);
1965 }
1966
1967 // The lock has been dropped so we can free resources.
1968 // Free up either the old cache or the new cache if we allocated one.
1969 if (to_dealloc_jmeths != NULL) {
1970 FreeHeap(to_dealloc_jmeths);
1971 }
1972 // free up the new ID since it wasn't needed
1973 if (to_dealloc_id != NULL) {
1974 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1975 }
1976 }
1977 return id;
1978 }
1979
1980 // Figure out how many jmethodIDs haven't been allocated, and make
1981 // sure space for them is pre-allocated. This makes getting all
1982 // method ids much, much faster with classes with more than 8
1983 // methods, and has a *substantial* effect on performance with jvmti
1984 // code that loads all jmethodIDs for all classes.
1985 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1986 int new_jmeths = 0;
1987 int length = methods()->length();
1988 for (int index = start_offset; index < length; index++) {
1989 Method* m = methods()->at(index);
1990 jmethodID id = m->find_jmethod_id_or_null();
1991 if (id == NULL) {
1992 new_jmeths++;
1993 }
1994 }
1995 if (new_jmeths != 0) {
1996 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1997 }
1998 }
1999
2000 // Common code to fetch the jmethodID from the cache or update the
2001 // cache with the new jmethodID. This function should never do anything
2002 // that causes the caller to go to a safepoint or we can deadlock with
2003 // the VMThread or have cache consistency issues.
2004 //
2005 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2006 size_t idnum, jmethodID new_id,
2007 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2008 jmethodID** to_dealloc_jmeths_p) {
2009 assert(new_id != NULL, "sanity check");
2010 assert(to_dealloc_id_p != NULL, "sanity check");
2011 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2012 assert(Threads::number_of_threads() == 0 ||
2013 SafepointSynchronize::is_at_safepoint() ||
2014 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2015
2016 // reacquire the cache - we are locked, single threaded or at a safepoint
2017 jmethodID* jmeths = methods_jmethod_ids_acquire();
2018 jmethodID id = NULL;
2019 size_t length = 0;
2020
2021 if (jmeths == NULL || // no cache yet
2022 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2023 if (jmeths != NULL) {
2024 // copy any existing entries from the old cache
2025 for (size_t index = 0; index < length; index++) {
2026 new_jmeths[index+1] = jmeths[index+1];
2027 }
2028 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2029 }
2030 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2031 } else {
2032 // fetch jmethodID (if any) from the existing cache
2033 id = jmeths[idnum+1];
2034 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2035 }
2036 if (id == NULL) {
2037 // No matching jmethodID in the existing cache or we have a new
2038 // cache or we just grew the cache. This cache write is done here
2039 // by the first thread to win the foot race because a jmethodID
2040 // needs to be unique once it is generally available.
2041 id = new_id;
2042
2043 // The jmethodID cache can be read while unlocked so we have to
2044 // make sure the new jmethodID is complete before installing it
2045 // in the cache.
2046 OrderAccess::release_store(&jmeths[idnum+1], id);
2047 } else {
2048 *to_dealloc_id_p = new_id; // save new id for later delete
2049 }
2050 return id;
2051 }
2052
2053
2054 // Common code to get the jmethodID cache length and the jmethodID
2055 // value at index idnum if there is one.
2056 //
2057 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2058 size_t idnum, size_t *length_p, jmethodID* id_p) {
2059 assert(cache != NULL, "sanity check");
2060 assert(length_p != NULL, "sanity check");
2061 assert(id_p != NULL, "sanity check");
2062
2063 // cache size is stored in element[0], other elements offset by one
2064 *length_p = (size_t)cache[0];
2065 if (*length_p <= idnum) { // cache is too short
2066 *id_p = NULL;
2067 } else {
2068 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2069 }
2070 }
2071
2072
2073 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2074 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2075 size_t idnum = (size_t)method->method_idnum();
2076 jmethodID* jmeths = methods_jmethod_ids_acquire();
2077 size_t length; // length assigned as debugging crumb
2078 jmethodID id = NULL;
2079 if (jmeths != NULL && // If there is a cache
2080 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2081 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2082 }
2083 return id;
2084 }
2085
2086 inline DependencyContext InstanceKlass::dependencies() {
2087 DependencyContext dep_context(&_dep_context);
2088 return dep_context;
2089 }
2090
2091 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2092 return dependencies().mark_dependent_nmethods(changes);
2093 }
2094
2095 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2096 dependencies().add_dependent_nmethod(nm);
2097 }
2098
2099 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2100 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2101 }
2102
2103 #ifndef PRODUCT
2104 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2105 dependencies().print_dependent_nmethods(verbose);
2106 }
2107
2108 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2109 return dependencies().is_dependent_nmethod(nm);
2110 }
2111 #endif //PRODUCT
2112
2113 void InstanceKlass::clean_weak_instanceklass_links() {
2114 clean_implementors_list();
2115 clean_method_data();
2116
2117 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2118 DependencyContext dep_context(&_dep_context);
2119 dep_context.expunge_stale_entries();
2120 }
2121
2122 void InstanceKlass::clean_implementors_list() {
2123 assert(is_loader_alive(), "this klass should be live");
2124 if (is_interface()) {
2125 if (ClassUnloading) {
2126 Klass* impl = implementor();
2127 if (impl != NULL) {
2128 if (!impl->is_loader_alive()) {
2129 // remove this guy
2130 Klass** klass = adr_implementor();
2131 assert(klass != NULL, "null klass");
2132 if (klass != NULL) {
2133 *klass = NULL;
2134 }
2135 }
2136 }
2137 }
2138 }
2139 }
2140
2141 void InstanceKlass::clean_method_data() {
2142 for (int m = 0; m < methods()->length(); m++) {
2143 MethodData* mdo = methods()->at(m)->method_data();
2144 if (mdo != NULL) {
2145 mdo->clean_method_data(/*always_clean*/false);
2146 }
2147 }
2148 }
2149
2150 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2151 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2152 ResourceMark rm;
2153 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2154 return false;
2155 }
2156
2157 Array<Klass*>* local_interfaces = this->local_interfaces();
2158 if (local_interfaces != NULL) {
2159 int length = local_interfaces->length();
2160 for (int i = 0; i < length; i++) {
2161 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2162 if (!intf->has_passed_fingerprint_check()) {
2163 ResourceMark rm;
2164 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2165 return false;
2166 }
2167 }
2168 }
2169
2170 return true;
2171 }
2172
2173 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2174 #if INCLUDE_AOT
2175 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2176 if (CalculateClassFingerprint) {
2177 // (1) We are running AOT to generate a shared library.
2178 return true;
2179 }
2180 if (DumpSharedSpaces) {
2181 // (2) We are running -Xshare:dump to create a shared archive
2182 return true;
2183 }
2184 if (UseAOT && is_anonymous) {
2185 // (3) We are using AOT code from a shared library and see an anonymous class
2186 return true;
2187 }
2188 #endif
2189
2190 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2191 // but do not store the 64-bit fingerprint to save space.
2192 return false;
2193 }
2194
2195 bool InstanceKlass::has_stored_fingerprint() const {
2196 #if INCLUDE_AOT
2197 return should_store_fingerprint() || is_shared();
2198 #else
2199 return false;
2200 #endif
2201 }
2202
2203 uint64_t InstanceKlass::get_stored_fingerprint() const {
2204 address adr = adr_fingerprint();
2205 if (adr != NULL) {
2206 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2207 }
2208 return 0;
2209 }
2210
2211 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2212 address adr = adr_fingerprint();
2213 if (adr != NULL) {
2214 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2215
2216 ResourceMark rm;
2217 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2218 }
2219 }
2220
2221 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2222 Klass::metaspace_pointers_do(it);
2223
2224 if (log_is_enabled(Trace, cds)) {
2225 ResourceMark rm;
2226 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2227 }
2228
2229 it->push(&_annotations);
2230 it->push((Klass**)&_array_klasses);
2231 it->push(&_constants);
2232 it->push(&_inner_classes);
2233 it->push(&_array_name);
2234 #if INCLUDE_JVMTI
2235 it->push(&_previous_versions);
2236 #endif
2237 it->push(&_methods);
2238 it->push(&_default_methods);
2239 it->push(&_local_interfaces);
2240 it->push(&_transitive_interfaces);
2241 it->push(&_method_ordering);
2242 it->push(&_default_vtable_indices);
2243 it->push(&_fields);
2244
2245 if (itable_length() > 0) {
2246 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2247 int method_table_offset_in_words = ioe->offset()/wordSize;
2248 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2249 / itableOffsetEntry::size();
2250
2251 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2252 if (ioe->interface_klass() != NULL) {
2253 it->push(ioe->interface_klass_addr());
2254 itableMethodEntry* ime = ioe->first_method_entry(this);
2255 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2256 for (int index = 0; index < n; index ++) {
2257 it->push(ime[index].method_addr());
2258 }
2259 }
2260 }
2261 }
2262
2263 it->push(&_nest_members);
2264 }
2265
2266 void InstanceKlass::remove_unshareable_info() {
2267 Klass::remove_unshareable_info();
2268
2269 if (is_in_error_state()) {
2270 // Classes are attempted to link during dumping and may fail,
2271 // but these classes are still in the dictionary and class list in CLD.
2272 // Check in_error state first because in_error is > linked state, so
2273 // is_linked() is true.
2274 // If there's a linking error, there is nothing else to remove.
2275 return;
2276 }
2277
2278 // Unlink the class
2279 if (is_linked()) {
2280 unlink_class();
2281 }
2282 init_implementor();
2283
2284 constants()->remove_unshareable_info();
2285
2286 for (int i = 0; i < methods()->length(); i++) {
2287 Method* m = methods()->at(i);
2288 m->remove_unshareable_info();
2289 }
2290
2291 // do array classes also.
2292 if (array_klasses() != NULL) {
2293 array_klasses()->remove_unshareable_info();
2294 }
2295
2296 // These are not allocated from metaspace, but they should should all be empty
2297 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2298 guarantee(_source_debug_extension == NULL, "must be");
2299 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2300 guarantee(_osr_nmethods_head == NULL, "must be");
2301
2302 #if INCLUDE_JVMTI
2303 guarantee(_breakpoints == NULL, "must be");
2304 guarantee(_previous_versions == NULL, "must be");
2305 #endif
2306
2307 _init_thread = NULL;
2308 _methods_jmethod_ids = NULL;
2309 _jni_ids = NULL;
2310 _oop_map_cache = NULL;
2311 // clear _nest_host to ensure re-load at runtime
2312 _nest_host = NULL;
2313 }
2314
2315 void InstanceKlass::remove_java_mirror() {
2316 Klass::remove_java_mirror();
2317
2318 // do array classes also.
2319 if (array_klasses() != NULL) {
2320 array_klasses()->remove_java_mirror();
2321 }
2322 }
2323
2324 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2325 set_package(loader_data, CHECK);
2326 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2327
2328 Array<Method*>* methods = this->methods();
2329 int num_methods = methods->length();
2330 for (int index2 = 0; index2 < num_methods; ++index2) {
2331 methodHandle m(THREAD, methods->at(index2));
2332 m->restore_unshareable_info(CHECK);
2333 }
2334 if (JvmtiExport::has_redefined_a_class()) {
2335 // Reinitialize vtable because RedefineClasses may have changed some
2336 // entries in this vtable for super classes so the CDS vtable might
2337 // point to old or obsolete entries. RedefineClasses doesn't fix up
2338 // vtables in the shared system dictionary, only the main one.
2339 // It also redefines the itable too so fix that too.
2340 ResourceMark rm(THREAD);
2341 vtable().initialize_vtable(false, CHECK);
2342 itable().initialize_itable(false, CHECK);
2343 }
2344
2345 // restore constant pool resolved references
2346 constants()->restore_unshareable_info(CHECK);
2347
2348 if (array_klasses() != NULL) {
2349 // Array classes have null protection domain.
2350 // --> see ArrayKlass::complete_create_array_klass()
2351 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2352 }
2353 }
2354
2355 // returns true IFF is_in_error_state() has been changed as a result of this call.
2356 bool InstanceKlass::check_sharing_error_state() {
2357 assert(DumpSharedSpaces, "should only be called during dumping");
2358 bool old_state = is_in_error_state();
2359
2360 if (!is_in_error_state()) {
2361 bool bad = false;
2362 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2363 if (sup->is_in_error_state()) {
2364 bad = true;
2365 break;
2366 }
2367 }
2368 if (!bad) {
2369 Array<Klass*>* interfaces = transitive_interfaces();
2370 for (int i = 0; i < interfaces->length(); i++) {
2371 Klass* iface = interfaces->at(i);
2372 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2373 bad = true;
2374 break;
2375 }
2376 }
2377 }
2378
2379 if (bad) {
2380 set_in_error_state();
2381 }
2382 }
2383
2384 return (old_state != is_in_error_state());
2385 }
2386
2387 #if INCLUDE_JVMTI
2388 static void clear_all_breakpoints(Method* m) {
2389 m->clear_all_breakpoints();
2390 }
2391 #endif
2392
2393 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2394 // notify the debugger
2395 if (JvmtiExport::should_post_class_unload()) {
2396 JvmtiExport::post_class_unload(ik);
2397 }
2398
2399 // notify ClassLoadingService of class unload
2400 ClassLoadingService::notify_class_unloaded(ik);
2401 }
2402
2403 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2404 // Clean up C heap
2405 ik->release_C_heap_structures();
2406 ik->constants()->release_C_heap_structures();
2407 }
2408
2409 void InstanceKlass::release_C_heap_structures() {
2410 // Can't release the constant pool here because the constant pool can be
2411 // deallocated separately from the InstanceKlass for default methods and
2412 // redefine classes.
2413
2414 // Deallocate oop map cache
2415 if (_oop_map_cache != NULL) {
2416 delete _oop_map_cache;
2417 _oop_map_cache = NULL;
2418 }
2419
2420 // Deallocate JNI identifiers for jfieldIDs
2421 JNIid::deallocate(jni_ids());
2422 set_jni_ids(NULL);
2423
2424 jmethodID* jmeths = methods_jmethod_ids_acquire();
2425 if (jmeths != (jmethodID*)NULL) {
2426 release_set_methods_jmethod_ids(NULL);
2427 FreeHeap(jmeths);
2428 }
2429
2430 // Release dependencies.
2431 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2432 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2433 // context can contain live dependencies, since there's a race between nmethod &
2434 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2435 // dependencies aren't removed from the context associated with the class (see
2436 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2437 // live dependencies pointing to unloaded nmethods and causes a crash in
2438 // DC::remove_all_dependents() when it touches unloaded nmethod.
2439 dependencies().wipe();
2440
2441 #if INCLUDE_JVMTI
2442 // Deallocate breakpoint records
2443 if (breakpoints() != 0x0) {
2444 methods_do(clear_all_breakpoints);
2445 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2446 }
2447
2448 // deallocate the cached class file
2449 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2450 os::free(_cached_class_file);
2451 _cached_class_file = NULL;
2452 }
2453 #endif
2454
2455 // Decrement symbol reference counts associated with the unloaded class.
2456 if (_name != NULL) _name->decrement_refcount();
2457 // unreference array name derived from this class name (arrays of an unloaded
2458 // class can't be referenced anymore).
2459 if (_array_name != NULL) _array_name->decrement_refcount();
2460 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2461 }
2462
2463 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2464 if (array == NULL) {
2465 _source_debug_extension = NULL;
2466 } else {
2467 // Adding one to the attribute length in order to store a null terminator
2468 // character could cause an overflow because the attribute length is
2469 // already coded with an u4 in the classfile, but in practice, it's
2470 // unlikely to happen.
2471 assert((length+1) > length, "Overflow checking");
2472 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2473 for (int i = 0; i < length; i++) {
2474 sde[i] = array[i];
2475 }
2476 sde[length] = '\0';
2477 _source_debug_extension = sde;
2478 }
2479 }
2480
2481 const char* InstanceKlass::signature_name() const {
2482 int hash_len = 0;
2483 char hash_buf[40];
2484
2485 // If this is an anonymous class, append a hash to make the name unique
2486 if (is_anonymous()) {
2487 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2488 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2489 hash_len = (int)strlen(hash_buf);
2490 }
2491
2492 // Get the internal name as a c string
2493 const char* src = (const char*) (name()->as_C_string());
2494 const int src_length = (int)strlen(src);
2495
2496 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2497
2498 // Add L as type indicator
2499 int dest_index = 0;
2500 dest[dest_index++] = 'L';
2501
2502 // Add the actual class name
2503 for (int src_index = 0; src_index < src_length; ) {
2504 dest[dest_index++] = src[src_index++];
2505 }
2506
2507 // If we have a hash, append it
2508 for (int hash_index = 0; hash_index < hash_len; ) {
2509 dest[dest_index++] = hash_buf[hash_index++];
2510 }
2511
2512 // Add the semicolon and the NULL
2513 dest[dest_index++] = ';';
2514 dest[dest_index] = '\0';
2515 return dest;
2516 }
2517
2518 // Used to obtain the package name from a fully qualified class name.
2519 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2520 if (name == NULL) {
2521 return NULL;
2522 } else {
2523 if (name->utf8_length() <= 0) {
2524 return NULL;
2525 }
2526 ResourceMark rm;
2527 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2528 if (package_name == NULL) {
2529 return NULL;
2530 }
2531 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2532 return pkg_name;
2533 }
2534 }
2535
2536 ModuleEntry* InstanceKlass::module() const {
2537 if (!in_unnamed_package()) {
2538 return _package_entry->module();
2539 }
2540 const Klass* host = host_klass();
2541 if (host == NULL) {
2542 return class_loader_data()->unnamed_module();
2543 }
2544 return host->class_loader_data()->unnamed_module();
2545 }
2546
2547 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2548
2549 // ensure java/ packages only loaded by boot or platform builtin loaders
2550 check_prohibited_package(name(), loader_data, CHECK);
2551
2552 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2553
2554 if (pkg_name != NULL && loader_data != NULL) {
2555
2556 // Find in class loader's package entry table.
2557 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2558
2559 // If the package name is not found in the loader's package
2560 // entry table, it is an indication that the package has not
2561 // been defined. Consider it defined within the unnamed module.
2562 if (_package_entry == NULL) {
2563 ResourceMark rm;
2564
2565 if (!ModuleEntryTable::javabase_defined()) {
2566 // Before java.base is defined during bootstrapping, define all packages in
2567 // the java.base module. If a non-java.base package is erroneously placed
2568 // in the java.base module it will be caught later when java.base
2569 // is defined by ModuleEntryTable::verify_javabase_packages check.
2570 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2571 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2572 } else {
2573 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2574 _package_entry = loader_data->packages()->lookup(pkg_name,
2575 loader_data->unnamed_module());
2576 }
2577
2578 // A package should have been successfully created
2579 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2580 name()->as_C_string(), loader_data->loader_name_and_id());
2581 }
2582
2583 if (log_is_enabled(Debug, module)) {
2584 ResourceMark rm;
2585 ModuleEntry* m = _package_entry->module();
2586 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2587 external_name(),
2588 pkg_name->as_C_string(),
2589 loader_data->loader_name_and_id(),
2590 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2591 }
2592 } else {
2593 ResourceMark rm;
2594 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2595 external_name(),
2596 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2597 UNNAMED_MODULE);
2598 }
2599 }
2600
2601
2602 // different versions of is_same_class_package
2603
2604 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2605 oop classloader1 = this->class_loader();
2606 PackageEntry* classpkg1 = this->package();
2607 if (class2->is_objArray_klass()) {
2608 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2609 }
2610
2611 oop classloader2;
2612 PackageEntry* classpkg2;
2613 if (class2->is_instance_klass()) {
2614 classloader2 = class2->class_loader();
2615 classpkg2 = class2->package();
2616 } else {
2617 assert(class2->is_typeArray_klass(), "should be type array");
2618 classloader2 = NULL;
2619 classpkg2 = NULL;
2620 }
2621
2622 // Same package is determined by comparing class loader
2623 // and package entries. Both must be the same. This rule
2624 // applies even to classes that are defined in the unnamed
2625 // package, they still must have the same class loader.
2626 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2627 return true;
2628 }
2629
2630 return false;
2631 }
2632
2633 // return true if this class and other_class are in the same package. Classloader
2634 // and classname information is enough to determine a class's package
2635 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2636 const Symbol* other_class_name) const {
2637 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2638 return false;
2639 }
2640 if (name()->fast_compare(other_class_name) == 0) {
2641 return true;
2642 }
2643
2644 {
2645 ResourceMark rm;
2646
2647 bool bad_class_name = false;
2648 const char* other_pkg =
2649 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2650 if (bad_class_name) {
2651 return false;
2652 }
2653 // Check that package_from_name() returns NULL, not "", if there is no package.
2654 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2655
2656 const Symbol* const this_package_name =
2657 this->package() != NULL ? this->package()->name() : NULL;
2658
2659 if (this_package_name == NULL || other_pkg == NULL) {
2660 // One of the two doesn't have a package. Only return true if the other
2661 // one also doesn't have a package.
2662 return (const char*)this_package_name == other_pkg;
2663 }
2664
2665 // Check if package is identical
2666 return this_package_name->equals(other_pkg);
2667 }
2668 }
2669
2670 // Returns true iff super_method can be overridden by a method in targetclassname
2671 // See JLS 3rd edition 8.4.6.1
2672 // Assumes name-signature match
2673 // "this" is InstanceKlass of super_method which must exist
2674 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2675 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2676 // Private methods can not be overridden
2677 if (super_method->is_private()) {
2678 return false;
2679 }
2680 // If super method is accessible, then override
2681 if ((super_method->is_protected()) ||
2682 (super_method->is_public())) {
2683 return true;
2684 }
2685 // Package-private methods are not inherited outside of package
2686 assert(super_method->is_package_private(), "must be package private");
2687 return(is_same_class_package(targetclassloader(), targetclassname));
2688 }
2689
2690 // Only boot and platform class loaders can define classes in "java/" packages.
2691 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2692 ClassLoaderData* loader_data,
2693 TRAPS) {
2694 if (!loader_data->is_boot_class_loader_data() &&
2695 !loader_data->is_platform_class_loader_data() &&
2696 class_name != NULL) {
2697 ResourceMark rm(THREAD);
2698 char* name = class_name->as_C_string();
2699 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2700 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2701 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2702 name = pkg_name->as_C_string();
2703 const char* class_loader_name = loader_data->loader_name_and_id();
2704 StringUtils::replace_no_expand(name, "/", ".");
2705 const char* msg_text1 = "Class loader (instance of): ";
2706 const char* msg_text2 = " tried to load prohibited package name: ";
2707 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2708 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2709 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2710 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2711 }
2712 }
2713 return;
2714 }
2715
2716 // tell if two classes have the same enclosing class (at package level)
2717 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2718 if (class2 == this) return true;
2719 if (!class2->is_instance_klass()) return false;
2720
2721 // must be in same package before we try anything else
2722 if (!is_same_class_package(class2))
2723 return false;
2724
2725 // As long as there is an outer_this.getEnclosingClass,
2726 // shift the search outward.
2727 const InstanceKlass* outer_this = this;
2728 for (;;) {
2729 // As we walk along, look for equalities between outer_this and class2.
2730 // Eventually, the walks will terminate as outer_this stops
2731 // at the top-level class around the original class.
2732 bool ignore_inner_is_member;
2733 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2734 CHECK_false);
2735 if (next == NULL) break;
2736 if (next == class2) return true;
2737 outer_this = InstanceKlass::cast(next);
2738 }
2739
2740 // Now do the same for class2.
2741 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2742 for (;;) {
2743 bool ignore_inner_is_member;
2744 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2745 CHECK_false);
2746 if (next == NULL) break;
2747 // Might as well check the new outer against all available values.
2748 if (next == this) return true;
2749 if (next == outer_this) return true;
2750 outer2 = InstanceKlass::cast(next);
2751 }
2752
2753 // If by this point we have not found an equality between the
2754 // two classes, we know they are in separate package members.
2755 return false;
2756 }
2757
2758 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2759 constantPoolHandle i_cp(THREAD, constants());
2760 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2761 int ioff = iter.inner_class_info_index();
2762 if (ioff != 0) {
2763 // Check to see if the name matches the class we're looking for
2764 // before attempting to find the class.
2765 if (i_cp->klass_name_at_matches(this, ioff)) {
2766 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2767 if (this == inner_klass) {
2768 *ooff = iter.outer_class_info_index();
2769 *noff = iter.inner_name_index();
2770 return true;
2771 }
2772 }
2773 }
2774 }
2775 return false;
2776 }
2777
2778 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2779 InstanceKlass* outer_klass = NULL;
2780 *inner_is_member = false;
2781 int ooff = 0, noff = 0;
2782 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2783 if (has_inner_classes_attr) {
2784 constantPoolHandle i_cp(THREAD, constants());
2785 if (ooff != 0) {
2786 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2787 outer_klass = InstanceKlass::cast(ok);
2788 *inner_is_member = true;
2789 }
2790 if (NULL == outer_klass) {
2791 // It may be anonymous; try for that.
2792 int encl_method_class_idx = enclosing_method_class_index();
2793 if (encl_method_class_idx != 0) {
2794 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2795 outer_klass = InstanceKlass::cast(ok);
2796 *inner_is_member = false;
2797 }
2798 }
2799 }
2800
2801 // If no inner class attribute found for this class.
2802 if (NULL == outer_klass) return NULL;
2803
2804 // Throws an exception if outer klass has not declared k as an inner klass
2805 // We need evidence that each klass knows about the other, or else
2806 // the system could allow a spoof of an inner class to gain access rights.
2807 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2808 return outer_klass;
2809 }
2810
2811 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2812 jint access = access_flags().as_int();
2813
2814 // But check if it happens to be member class.
2815 InnerClassesIterator iter(this);
2816 for (; !iter.done(); iter.next()) {
2817 int ioff = iter.inner_class_info_index();
2818 // Inner class attribute can be zero, skip it.
2819 // Strange but true: JVM spec. allows null inner class refs.
2820 if (ioff == 0) continue;
2821
2822 // only look at classes that are already loaded
2823 // since we are looking for the flags for our self.
2824 Symbol* inner_name = constants()->klass_name_at(ioff);
2825 if (name() == inner_name) {
2826 // This is really a member class.
2827 access = iter.inner_access_flags();
2828 break;
2829 }
2830 }
2831 // Remember to strip ACC_SUPER bit
2832 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2833 }
2834
2835 jint InstanceKlass::jvmti_class_status() const {
2836 jint result = 0;
2837
2838 if (is_linked()) {
2839 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2840 }
2841
2842 if (is_initialized()) {
2843 assert(is_linked(), "Class status is not consistent");
2844 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2845 }
2846 if (is_in_error_state()) {
2847 result |= JVMTI_CLASS_STATUS_ERROR;
2848 }
2849 return result;
2850 }
2851
2852 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2853 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2854 int method_table_offset_in_words = ioe->offset()/wordSize;
2855 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2856 / itableOffsetEntry::size();
2857
2858 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2859 // If the interface isn't implemented by the receiver class,
2860 // the VM should throw IncompatibleClassChangeError.
2861 if (cnt >= nof_interfaces) {
2862 ResourceMark rm(THREAD);
2863 stringStream ss;
2864 bool same_module = (module() == holder->module());
2865 ss.print("Receiver class %s does not implement "
2866 "the interface %s defining the method to be called "
2867 "(%s%s%s)",
2868 external_name(), holder->external_name(),
2869 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2870 (same_module) ? "" : "; ",
2871 (same_module) ? "" : holder->class_in_module_of_loader());
2872 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2873 }
2874
2875 Klass* ik = ioe->interface_klass();
2876 if (ik == holder) break;
2877 }
2878
2879 itableMethodEntry* ime = ioe->first_method_entry(this);
2880 Method* m = ime[index].method();
2881 if (m == NULL) {
2882 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2883 }
2884 return m;
2885 }
2886
2887
2888 #if INCLUDE_JVMTI
2889 // update default_methods for redefineclasses for methods that are
2890 // not yet in the vtable due to concurrent subclass define and superinterface
2891 // redefinition
2892 // Note: those in the vtable, should have been updated via adjust_method_entries
2893 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2894 // search the default_methods for uses of either obsolete or EMCP methods
2895 if (default_methods() != NULL) {
2896 for (int index = 0; index < default_methods()->length(); index ++) {
2897 Method* old_method = default_methods()->at(index);
2898 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2899 continue; // skip uninteresting entries
2900 }
2901 assert(!old_method->is_deleted(), "default methods may not be deleted");
2902
2903 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2904
2905 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2906 assert(old_method != new_method, "sanity check");
2907
2908 default_methods()->at_put(index, new_method);
2909 if (log_is_enabled(Info, redefine, class, update)) {
2910 ResourceMark rm;
2911 if (!(*trace_name_printed)) {
2912 log_info(redefine, class, update)
2913 ("adjust: klassname=%s default methods from name=%s",
2914 external_name(), old_method->method_holder()->external_name());
2915 *trace_name_printed = true;
2916 }
2917 log_debug(redefine, class, update, vtables)
2918 ("default method update: %s(%s) ",
2919 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2920 }
2921 }
2922 }
2923 }
2924 #endif // INCLUDE_JVMTI
2925
2926 // On-stack replacement stuff
2927 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2928 // only one compilation can be active
2929 {
2930 // This is a short non-blocking critical region, so the no safepoint check is ok.
2931 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2932 assert(n->is_osr_method(), "wrong kind of nmethod");
2933 n->set_osr_link(osr_nmethods_head());
2934 set_osr_nmethods_head(n);
2935 // Raise the highest osr level if necessary
2936 if (TieredCompilation) {
2937 Method* m = n->method();
2938 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2939 }
2940 }
2941
2942 // Get rid of the osr methods for the same bci that have lower levels.
2943 if (TieredCompilation) {
2944 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2945 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2946 if (inv != NULL && inv->is_in_use()) {
2947 inv->make_not_entrant();
2948 }
2949 }
2950 }
2951 }
2952
2953 // Remove osr nmethod from the list. Return true if found and removed.
2954 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2955 // This is a short non-blocking critical region, so the no safepoint check is ok.
2956 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2957 assert(n->is_osr_method(), "wrong kind of nmethod");
2958 nmethod* last = NULL;
2959 nmethod* cur = osr_nmethods_head();
2960 int max_level = CompLevel_none; // Find the max comp level excluding n
2961 Method* m = n->method();
2962 // Search for match
2963 bool found = false;
2964 while(cur != NULL && cur != n) {
2965 if (TieredCompilation && m == cur->method()) {
2966 // Find max level before n
2967 max_level = MAX2(max_level, cur->comp_level());
2968 }
2969 last = cur;
2970 cur = cur->osr_link();
2971 }
2972 nmethod* next = NULL;
2973 if (cur == n) {
2974 found = true;
2975 next = cur->osr_link();
2976 if (last == NULL) {
2977 // Remove first element
2978 set_osr_nmethods_head(next);
2979 } else {
2980 last->set_osr_link(next);
2981 }
2982 }
2983 n->set_osr_link(NULL);
2984 if (TieredCompilation) {
2985 cur = next;
2986 while (cur != NULL) {
2987 // Find max level after n
2988 if (m == cur->method()) {
2989 max_level = MAX2(max_level, cur->comp_level());
2990 }
2991 cur = cur->osr_link();
2992 }
2993 m->set_highest_osr_comp_level(max_level);
2994 }
2995 return found;
2996 }
2997
2998 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2999 // This is a short non-blocking critical region, so the no safepoint check is ok.
3000 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3001 nmethod* osr = osr_nmethods_head();
3002 int found = 0;
3003 while (osr != NULL) {
3004 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3005 if (osr->method() == m) {
3006 osr->mark_for_deoptimization();
3007 found++;
3008 }
3009 osr = osr->osr_link();
3010 }
3011 return found;
3012 }
3013
3014 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3015 // This is a short non-blocking critical region, so the no safepoint check is ok.
3016 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3017 nmethod* osr = osr_nmethods_head();
3018 nmethod* best = NULL;
3019 while (osr != NULL) {
3020 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3021 // There can be a time when a c1 osr method exists but we are waiting
3022 // for a c2 version. When c2 completes its osr nmethod we will trash
3023 // the c1 version and only be able to find the c2 version. However
3024 // while we overflow in the c1 code at back branches we don't want to
3025 // try and switch to the same code as we are already running
3026
3027 if (osr->method() == m &&
3028 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3029 if (match_level) {
3030 if (osr->comp_level() == comp_level) {
3031 // Found a match - return it.
3032 return osr;
3033 }
3034 } else {
3035 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3036 if (osr->comp_level() == CompLevel_highest_tier) {
3037 // Found the best possible - return it.
3038 return osr;
3039 }
3040 best = osr;
3041 }
3042 }
3043 }
3044 osr = osr->osr_link();
3045 }
3046 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3047 return best;
3048 }
3049 return NULL;
3050 }
3051
3052 // -----------------------------------------------------------------------------------------------------
3053 // Printing
3054
3055 #ifndef PRODUCT
3056
3057 #define BULLET " - "
3058
3059 static const char* state_names[] = {
3060 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3061 };
3062
3063 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3064 for (int i = 0; i < len; i++) {
3065 intptr_t e = start[i];
3066 st->print("%d : " INTPTR_FORMAT, i, e);
3067 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3068 st->print(" ");
3069 ((Metadata*)e)->print_value_on(st);
3070 }
3071 st->cr();
3072 }
3073 }
3074
3075 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3076 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3077 }
3078
3079 void InstanceKlass::print_on(outputStream* st) const {
3080 assert(is_klass(), "must be klass");
3081 Klass::print_on(st);
3082
3083 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3084 st->print(BULLET"klass size: %d", size()); st->cr();
3085 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3086 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3087 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3088 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3089 st->print(BULLET"sub: ");
3090 Klass* sub = subklass();
3091 int n;
3092 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3093 if (n < MaxSubklassPrintSize) {
3094 sub->print_value_on(st);
3095 st->print(" ");
3096 }
3097 }
3098 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3099 st->cr();
3100
3101 if (is_interface()) {
3102 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3103 if (nof_implementors() == 1) {
3104 st->print_cr(BULLET"implementor: ");
3105 st->print(" ");
3106 implementor()->print_value_on(st);
3107 st->cr();
3108 }
3109 }
3110
3111 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3112 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3113 if (Verbose || WizardMode) {
3114 Array<Method*>* method_array = methods();
3115 for (int i = 0; i < method_array->length(); i++) {
3116 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3117 }
3118 }
3119 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3120 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3121 if (Verbose && default_methods() != NULL) {
3122 Array<Method*>* method_array = default_methods();
3123 for (int i = 0; i < method_array->length(); i++) {
3124 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3125 }
3126 }
3127 if (default_vtable_indices() != NULL) {
3128 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3129 }
3130 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3131 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3132 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3133 if (class_loader_data() != NULL) {
3134 st->print(BULLET"class loader data: ");
3135 class_loader_data()->print_value_on(st);
3136 st->cr();
3137 }
3138 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3139 if (source_file_name() != NULL) {
3140 st->print(BULLET"source file: ");
3141 source_file_name()->print_value_on(st);
3142 st->cr();
3143 }
3144 if (source_debug_extension() != NULL) {
3145 st->print(BULLET"source debug extension: ");
3146 st->print("%s", source_debug_extension());
3147 st->cr();
3148 }
3149 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3150 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3151 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3152 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3153 {
3154 bool have_pv = false;
3155 // previous versions are linked together through the InstanceKlass
3156 for (InstanceKlass* pv_node = previous_versions();
3157 pv_node != NULL;
3158 pv_node = pv_node->previous_versions()) {
3159 if (!have_pv)
3160 st->print(BULLET"previous version: ");
3161 have_pv = true;
3162 pv_node->constants()->print_value_on(st);
3163 }
3164 if (have_pv) st->cr();
3165 }
3166
3167 if (generic_signature() != NULL) {
3168 st->print(BULLET"generic signature: ");
3169 generic_signature()->print_value_on(st);
3170 st->cr();
3171 }
3172 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3173 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3174 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3175 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3176 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3177 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3178 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3179 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3180 FieldPrinter print_static_field(st);
3181 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3182 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3183 FieldPrinter print_nonstatic_field(st);
3184 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3185 ik->do_nonstatic_fields(&print_nonstatic_field);
3186
3187 st->print(BULLET"non-static oop maps: ");
3188 OopMapBlock* map = start_of_nonstatic_oop_maps();
3189 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3190 while (map < end_map) {
3191 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3192 map++;
3193 }
3194 st->cr();
3195 }
3196
3197 #endif //PRODUCT
3198
3199 void InstanceKlass::print_value_on(outputStream* st) const {
3200 assert(is_klass(), "must be klass");
3201 if (Verbose || WizardMode) access_flags().print_on(st);
3202 name()->print_value_on(st);
3203 }
3204
3205 #ifndef PRODUCT
3206
3207 void FieldPrinter::do_field(fieldDescriptor* fd) {
3208 _st->print(BULLET);
3209 if (_obj == NULL) {
3210 fd->print_on(_st);
3211 _st->cr();
3212 } else {
3213 fd->print_on_for(_st, _obj);
3214 _st->cr();
3215 }
3216 }
3217
3218
3219 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3220 Klass::oop_print_on(obj, st);
3221
3222 if (this == SystemDictionary::String_klass()) {
3223 typeArrayOop value = java_lang_String::value(obj);
3224 juint length = java_lang_String::length(obj);
3225 if (value != NULL &&
3226 value->is_typeArray() &&
3227 length <= (juint) value->length()) {
3228 st->print(BULLET"string: ");
3229 java_lang_String::print(obj, st);
3230 st->cr();
3231 if (!WizardMode) return; // that is enough
3232 }
3233 }
3234
3235 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3236 FieldPrinter print_field(st, obj);
3237 do_nonstatic_fields(&print_field);
3238
3239 if (this == SystemDictionary::Class_klass()) {
3240 st->print(BULLET"signature: ");
3241 java_lang_Class::print_signature(obj, st);
3242 st->cr();
3243 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3244 st->print(BULLET"fake entry for mirror: ");
3245 mirrored_klass->print_value_on_maybe_null(st);
3246 st->cr();
3247 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3248 st->print(BULLET"fake entry for array: ");
3249 array_klass->print_value_on_maybe_null(st);
3250 st->cr();
3251 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3252 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3253 Klass* real_klass = java_lang_Class::as_Klass(obj);
3254 if (real_klass != NULL && real_klass->is_instance_klass()) {
3255 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3256 }
3257 } else if (this == SystemDictionary::MethodType_klass()) {
3258 st->print(BULLET"signature: ");
3259 java_lang_invoke_MethodType::print_signature(obj, st);
3260 st->cr();
3261 }
3262 }
3263
3264 #endif //PRODUCT
3265
3266 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3267 st->print("a ");
3268 name()->print_value_on(st);
3269 obj->print_address_on(st);
3270 if (this == SystemDictionary::String_klass()
3271 && java_lang_String::value(obj) != NULL) {
3272 ResourceMark rm;
3273 int len = java_lang_String::length(obj);
3274 int plen = (len < 24 ? len : 12);
3275 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3276 st->print(" = \"%s\"", str);
3277 if (len > plen)
3278 st->print("...[%d]", len);
3279 } else if (this == SystemDictionary::Class_klass()) {
3280 Klass* k = java_lang_Class::as_Klass(obj);
3281 st->print(" = ");
3282 if (k != NULL) {
3283 k->print_value_on(st);
3284 } else {
3285 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3286 st->print("%s", tname ? tname : "type?");
3287 }
3288 } else if (this == SystemDictionary::MethodType_klass()) {
3289 st->print(" = ");
3290 java_lang_invoke_MethodType::print_signature(obj, st);
3291 } else if (java_lang_boxing_object::is_instance(obj)) {
3292 st->print(" = ");
3293 java_lang_boxing_object::print(obj, st);
3294 } else if (this == SystemDictionary::LambdaForm_klass()) {
3295 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3296 if (vmentry != NULL) {
3297 st->print(" => ");
3298 vmentry->print_value_on(st);
3299 }
3300 } else if (this == SystemDictionary::MemberName_klass()) {
3301 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3302 if (vmtarget != NULL) {
3303 st->print(" = ");
3304 vmtarget->print_value_on(st);
3305 } else {
3306 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3307 st->print(".");
3308 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3309 }
3310 }
3311 }
3312
3313 const char* InstanceKlass::internal_name() const {
3314 return external_name();
3315 }
3316
3317 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3318 const char* module_name,
3319 const ClassFileStream* cfs) const {
3320 if (!log_is_enabled(Info, class, load)) {
3321 return;
3322 }
3323
3324 ResourceMark rm;
3325 LogMessage(class, load) msg;
3326 stringStream info_stream;
3327
3328 // Name and class hierarchy info
3329 info_stream.print("%s", external_name());
3330
3331 // Source
3332 if (cfs != NULL) {
3333 if (cfs->source() != NULL) {
3334 if (module_name != NULL) {
3335 if (ClassLoader::is_modules_image(cfs->source())) {
3336 info_stream.print(" source: jrt:/%s", module_name);
3337 } else {
3338 info_stream.print(" source: %s", cfs->source());
3339 }
3340 } else {
3341 info_stream.print(" source: %s", cfs->source());
3342 }
3343 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3344 Thread* THREAD = Thread::current();
3345 Klass* caller =
3346 THREAD->is_Java_thread()
3347 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3348 : NULL;
3349 // caller can be NULL, for example, during a JVMTI VM_Init hook
3350 if (caller != NULL) {
3351 info_stream.print(" source: instance of %s", caller->external_name());
3352 } else {
3353 // source is unknown
3354 }
3355 } else {
3356 oop class_loader = loader_data->class_loader();
3357 info_stream.print(" source: %s", class_loader->klass()->external_name());
3358 }
3359 } else {
3360 info_stream.print(" source: shared objects file");
3361 }
3362
3363 msg.info("%s", info_stream.as_string());
3364
3365 if (log_is_enabled(Debug, class, load)) {
3366 stringStream debug_stream;
3367
3368 // Class hierarchy info
3369 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3370 p2i(this), p2i(superklass()));
3371
3372 // Interfaces
3373 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3374 debug_stream.print(" interfaces:");
3375 int length = local_interfaces()->length();
3376 for (int i = 0; i < length; i++) {
3377 debug_stream.print(" " INTPTR_FORMAT,
3378 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3379 }
3380 }
3381
3382 // Class loader
3383 debug_stream.print(" loader: [");
3384 loader_data->print_value_on(&debug_stream);
3385 debug_stream.print("]");
3386
3387 // Classfile checksum
3388 if (cfs) {
3389 debug_stream.print(" bytes: %d checksum: %08x",
3390 cfs->length(),
3391 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3392 cfs->length()));
3393 }
3394
3395 msg.debug("%s", debug_stream.as_string());
3396 }
3397 }
3398
3399 #if INCLUDE_SERVICES
3400 // Size Statistics
3401 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3402 Klass::collect_statistics(sz);
3403
3404 sz->_inst_size = wordSize * size_helper();
3405 sz->_vtab_bytes = wordSize * vtable_length();
3406 sz->_itab_bytes = wordSize * itable_length();
3407 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3408
3409 int n = 0;
3410 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3411 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3412 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3413 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3414 n += (sz->_fields_bytes = sz->count_array(fields()));
3415 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3416 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3417 sz->_ro_bytes += n;
3418
3419 const ConstantPool* cp = constants();
3420 if (cp) {
3421 cp->collect_statistics(sz);
3422 }
3423
3424 const Annotations* anno = annotations();
3425 if (anno) {
3426 anno->collect_statistics(sz);
3427 }
3428
3429 const Array<Method*>* methods_array = methods();
3430 if (methods()) {
3431 for (int i = 0; i < methods_array->length(); i++) {
3432 Method* method = methods_array->at(i);
3433 if (method) {
3434 sz->_method_count ++;
3435 method->collect_statistics(sz);
3436 }
3437 }
3438 }
3439 }
3440 #endif // INCLUDE_SERVICES
3441
3442 // Verification
3443
3444 class VerifyFieldClosure: public BasicOopIterateClosure {
3445 protected:
3446 template <class T> void do_oop_work(T* p) {
3447 oop obj = RawAccess<>::oop_load(p);
3448 if (!oopDesc::is_oop_or_null(obj)) {
3449 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3450 Universe::print_on(tty);
3451 guarantee(false, "boom");
3452 }
3453 }
3454 public:
3455 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3456 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3457 };
3458
3459 void InstanceKlass::verify_on(outputStream* st) {
3460 #ifndef PRODUCT
3461 // Avoid redundant verifies, this really should be in product.
3462 if (_verify_count == Universe::verify_count()) return;
3463 _verify_count = Universe::verify_count();
3464 #endif
3465
3466 // Verify Klass
3467 Klass::verify_on(st);
3468
3469 // Verify that klass is present in ClassLoaderData
3470 guarantee(class_loader_data()->contains_klass(this),
3471 "this class isn't found in class loader data");
3472
3473 // Verify vtables
3474 if (is_linked()) {
3475 // $$$ This used to be done only for m/s collections. Doing it
3476 // always seemed a valid generalization. (DLD -- 6/00)
3477 vtable().verify(st);
3478 }
3479
3480 // Verify first subklass
3481 if (subklass() != NULL) {
3482 guarantee(subklass()->is_klass(), "should be klass");
3483 }
3484
3485 // Verify siblings
3486 Klass* super = this->super();
3487 Klass* sib = next_sibling();
3488 if (sib != NULL) {
3489 if (sib == this) {
3490 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3491 }
3492
3493 guarantee(sib->is_klass(), "should be klass");
3494 guarantee(sib->super() == super, "siblings should have same superklass");
3495 }
3496
3497 // Verify implementor fields
3498 Klass* im = implementor();
3499 if (im != NULL) {
3500 guarantee(is_interface(), "only interfaces should have implementor set");
3501 guarantee(im->is_klass(), "should be klass");
3502 guarantee(!im->is_interface() || im == this,
3503 "implementors cannot be interfaces");
3504 }
3505
3506 // Verify local interfaces
3507 if (local_interfaces()) {
3508 Array<Klass*>* local_interfaces = this->local_interfaces();
3509 for (int j = 0; j < local_interfaces->length(); j++) {
3510 Klass* e = local_interfaces->at(j);
3511 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3512 }
3513 }
3514
3515 // Verify transitive interfaces
3516 if (transitive_interfaces() != NULL) {
3517 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3518 for (int j = 0; j < transitive_interfaces->length(); j++) {
3519 Klass* e = transitive_interfaces->at(j);
3520 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3521 }
3522 }
3523
3524 // Verify methods
3525 if (methods() != NULL) {
3526 Array<Method*>* methods = this->methods();
3527 for (int j = 0; j < methods->length(); j++) {
3528 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3529 }
3530 for (int j = 0; j < methods->length() - 1; j++) {
3531 Method* m1 = methods->at(j);
3532 Method* m2 = methods->at(j + 1);
3533 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3534 }
3535 }
3536
3537 // Verify method ordering
3538 if (method_ordering() != NULL) {
3539 Array<int>* method_ordering = this->method_ordering();
3540 int length = method_ordering->length();
3541 if (JvmtiExport::can_maintain_original_method_order() ||
3542 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3543 guarantee(length == methods()->length(), "invalid method ordering length");
3544 jlong sum = 0;
3545 for (int j = 0; j < length; j++) {
3546 int original_index = method_ordering->at(j);
3547 guarantee(original_index >= 0, "invalid method ordering index");
3548 guarantee(original_index < length, "invalid method ordering index");
3549 sum += original_index;
3550 }
3551 // Verify sum of indices 0,1,...,length-1
3552 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3553 } else {
3554 guarantee(length == 0, "invalid method ordering length");
3555 }
3556 }
3557
3558 // Verify default methods
3559 if (default_methods() != NULL) {
3560 Array<Method*>* methods = this->default_methods();
3561 for (int j = 0; j < methods->length(); j++) {
3562 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3563 }
3564 for (int j = 0; j < methods->length() - 1; j++) {
3565 Method* m1 = methods->at(j);
3566 Method* m2 = methods->at(j + 1);
3567 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3568 }
3569 }
3570
3571 // Verify JNI static field identifiers
3572 if (jni_ids() != NULL) {
3573 jni_ids()->verify(this);
3574 }
3575
3576 // Verify other fields
3577 if (array_klasses() != NULL) {
3578 guarantee(array_klasses()->is_klass(), "should be klass");
3579 }
3580 if (constants() != NULL) {
3581 guarantee(constants()->is_constantPool(), "should be constant pool");
3582 }
3583 const Klass* host = host_klass();
3584 if (host != NULL) {
3585 guarantee(host->is_klass(), "should be klass");
3586 }
3587 }
3588
3589 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3590 Klass::oop_verify_on(obj, st);
3591 VerifyFieldClosure blk;
3592 obj->oop_iterate(&blk);
3593 }
3594
3595
3596 // JNIid class for jfieldIDs only
3597 // Note to reviewers:
3598 // These JNI functions are just moved over to column 1 and not changed
3599 // in the compressed oops workspace.
3600 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3601 _holder = holder;
3602 _offset = offset;
3603 _next = next;
3604 debug_only(_is_static_field_id = false;)
3605 }
3606
3607
3608 JNIid* JNIid::find(int offset) {
3609 JNIid* current = this;
3610 while (current != NULL) {
3611 if (current->offset() == offset) return current;
3612 current = current->next();
3613 }
3614 return NULL;
3615 }
3616
3617 void JNIid::deallocate(JNIid* current) {
3618 while (current != NULL) {
3619 JNIid* next = current->next();
3620 delete current;
3621 current = next;
3622 }
3623 }
3624
3625
3626 void JNIid::verify(Klass* holder) {
3627 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3628 int end_field_offset;
3629 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3630
3631 JNIid* current = this;
3632 while (current != NULL) {
3633 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3634 #ifdef ASSERT
3635 int o = current->offset();
3636 if (current->is_static_field_id()) {
3637 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3638 }
3639 #endif
3640 current = current->next();
3641 }
3642 }
3643
3644 #ifdef ASSERT
3645 void InstanceKlass::set_init_state(ClassState state) {
3646 bool good_state = is_shared() ? (_init_state <= state)
3647 : (_init_state < state);
3648 assert(good_state || state == allocated, "illegal state transition");
3649 _init_state = (u1)state;
3650 }
3651 #endif
3652
3653 #if INCLUDE_JVMTI
3654
3655 // RedefineClasses() support for previous versions
3656
3657 // Globally, there is at least one previous version of a class to walk
3658 // during class unloading, which is saved because old methods in the class
3659 // are still running. Otherwise the previous version list is cleaned up.
3660 bool InstanceKlass::_has_previous_versions = false;
3661
3662 // Returns true if there are previous versions of a class for class
3663 // unloading only. Also resets the flag to false. purge_previous_version
3664 // will set the flag to true if there are any left, i.e., if there's any
3665 // work to do for next time. This is to avoid the expensive code cache
3666 // walk in CLDG::do_unloading().
3667 bool InstanceKlass::has_previous_versions_and_reset() {
3668 bool ret = _has_previous_versions;
3669 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3670 ret ? "true" : "false");
3671 _has_previous_versions = false;
3672 return ret;
3673 }
3674
3675 // Purge previous versions before adding new previous versions of the class and
3676 // during class unloading.
3677 void InstanceKlass::purge_previous_version_list() {
3678 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3679 assert(has_been_redefined(), "Should only be called for main class");
3680
3681 // Quick exit.
3682 if (previous_versions() == NULL) {
3683 return;
3684 }
3685
3686 // This klass has previous versions so see what we can cleanup
3687 // while it is safe to do so.
3688
3689 int deleted_count = 0; // leave debugging breadcrumbs
3690 int live_count = 0;
3691 ClassLoaderData* loader_data = class_loader_data();
3692 assert(loader_data != NULL, "should never be null");
3693
3694 ResourceMark rm;
3695 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3696
3697 // previous versions are linked together through the InstanceKlass
3698 InstanceKlass* pv_node = previous_versions();
3699 InstanceKlass* last = this;
3700 int version = 0;
3701
3702 // check the previous versions list
3703 for (; pv_node != NULL; ) {
3704
3705 ConstantPool* pvcp = pv_node->constants();
3706 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3707
3708 if (!pvcp->on_stack()) {
3709 // If the constant pool isn't on stack, none of the methods
3710 // are executing. Unlink this previous_version.
3711 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3712 // so will be deallocated during the next phase of class unloading.
3713 log_trace(redefine, class, iklass, purge)
3714 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3715 // For debugging purposes.
3716 pv_node->set_is_scratch_class();
3717 // Unlink from previous version list.
3718 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3719 InstanceKlass* next = pv_node->previous_versions();
3720 pv_node->link_previous_versions(NULL); // point next to NULL
3721 last->link_previous_versions(next);
3722 // Add to the deallocate list after unlinking
3723 loader_data->add_to_deallocate_list(pv_node);
3724 pv_node = next;
3725 deleted_count++;
3726 version++;
3727 continue;
3728 } else {
3729 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3730 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3731 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3732 live_count++;
3733 // found a previous version for next time we do class unloading
3734 _has_previous_versions = true;
3735 }
3736
3737 // At least one method is live in this previous version.
3738 // Reset dead EMCP methods not to get breakpoints.
3739 // All methods are deallocated when all of the methods for this class are no
3740 // longer running.
3741 Array<Method*>* method_refs = pv_node->methods();
3742 if (method_refs != NULL) {
3743 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3744 for (int j = 0; j < method_refs->length(); j++) {
3745 Method* method = method_refs->at(j);
3746
3747 if (!method->on_stack()) {
3748 // no breakpoints for non-running methods
3749 if (method->is_running_emcp()) {
3750 method->set_running_emcp(false);
3751 }
3752 } else {
3753 assert (method->is_obsolete() || method->is_running_emcp(),
3754 "emcp method cannot run after emcp bit is cleared");
3755 log_trace(redefine, class, iklass, purge)
3756 ("purge: %s(%s): prev method @%d in version @%d is alive",
3757 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3758 }
3759 }
3760 }
3761 // next previous version
3762 last = pv_node;
3763 pv_node = pv_node->previous_versions();
3764 version++;
3765 }
3766 log_trace(redefine, class, iklass, purge)
3767 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3768 }
3769
3770 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3771 int emcp_method_count) {
3772 int obsolete_method_count = old_methods->length() - emcp_method_count;
3773
3774 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3775 _previous_versions != NULL) {
3776 // We have a mix of obsolete and EMCP methods so we have to
3777 // clear out any matching EMCP method entries the hard way.
3778 int local_count = 0;
3779 for (int i = 0; i < old_methods->length(); i++) {
3780 Method* old_method = old_methods->at(i);
3781 if (old_method->is_obsolete()) {
3782 // only obsolete methods are interesting
3783 Symbol* m_name = old_method->name();
3784 Symbol* m_signature = old_method->signature();
3785
3786 // previous versions are linked together through the InstanceKlass
3787 int j = 0;
3788 for (InstanceKlass* prev_version = _previous_versions;
3789 prev_version != NULL;
3790 prev_version = prev_version->previous_versions(), j++) {
3791
3792 Array<Method*>* method_refs = prev_version->methods();
3793 for (int k = 0; k < method_refs->length(); k++) {
3794 Method* method = method_refs->at(k);
3795
3796 if (!method->is_obsolete() &&
3797 method->name() == m_name &&
3798 method->signature() == m_signature) {
3799 // The current RedefineClasses() call has made all EMCP
3800 // versions of this method obsolete so mark it as obsolete
3801 log_trace(redefine, class, iklass, add)
3802 ("%s(%s): flush obsolete method @%d in version @%d",
3803 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3804
3805 method->set_is_obsolete();
3806 break;
3807 }
3808 }
3809
3810 // The previous loop may not find a matching EMCP method, but
3811 // that doesn't mean that we can optimize and not go any
3812 // further back in the PreviousVersion generations. The EMCP
3813 // method for this generation could have already been made obsolete,
3814 // but there still may be an older EMCP method that has not
3815 // been made obsolete.
3816 }
3817
3818 if (++local_count >= obsolete_method_count) {
3819 // no more obsolete methods so bail out now
3820 break;
3821 }
3822 }
3823 }
3824 }
3825 }
3826
3827 // Save the scratch_class as the previous version if any of the methods are running.
3828 // The previous_versions are used to set breakpoints in EMCP methods and they are
3829 // also used to clean MethodData links to redefined methods that are no longer running.
3830 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3831 int emcp_method_count) {
3832 assert(Thread::current()->is_VM_thread(),
3833 "only VMThread can add previous versions");
3834
3835 ResourceMark rm;
3836 log_trace(redefine, class, iklass, add)
3837 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3838
3839 // Clean out old previous versions for this class
3840 purge_previous_version_list();
3841
3842 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3843 // a previous redefinition may be made obsolete by this redefinition.
3844 Array<Method*>* old_methods = scratch_class->methods();
3845 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3846
3847 // If the constant pool for this previous version of the class
3848 // is not marked as being on the stack, then none of the methods
3849 // in this previous version of the class are on the stack so
3850 // we don't need to add this as a previous version.
3851 ConstantPool* cp_ref = scratch_class->constants();
3852 if (!cp_ref->on_stack()) {
3853 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3854 // For debugging purposes.
3855 scratch_class->set_is_scratch_class();
3856 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3857 return;
3858 }
3859
3860 if (emcp_method_count != 0) {
3861 // At least one method is still running, check for EMCP methods
3862 for (int i = 0; i < old_methods->length(); i++) {
3863 Method* old_method = old_methods->at(i);
3864 if (!old_method->is_obsolete() && old_method->on_stack()) {
3865 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3866 // we can add breakpoints for it.
3867
3868 // We set the method->on_stack bit during safepoints for class redefinition
3869 // and use this bit to set the is_running_emcp bit.
3870 // After the safepoint, the on_stack bit is cleared and the running emcp
3871 // method may exit. If so, we would set a breakpoint in a method that
3872 // is never reached, but this won't be noticeable to the programmer.
3873 old_method->set_running_emcp(true);
3874 log_trace(redefine, class, iklass, add)
3875 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3876 } else if (!old_method->is_obsolete()) {
3877 log_trace(redefine, class, iklass, add)
3878 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3879 }
3880 }
3881 }
3882
3883 // Add previous version if any methods are still running.
3884 // Set has_previous_version flag for processing during class unloading.
3885 _has_previous_versions = true;
3886 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3887 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3888 scratch_class->link_previous_versions(previous_versions());
3889 link_previous_versions(scratch_class);
3890 } // end add_previous_version()
3891
3892 #endif // INCLUDE_JVMTI
3893
3894 Method* InstanceKlass::method_with_idnum(int idnum) {
3895 Method* m = NULL;
3896 if (idnum < methods()->length()) {
3897 m = methods()->at(idnum);
3898 }
3899 if (m == NULL || m->method_idnum() != idnum) {
3900 for (int index = 0; index < methods()->length(); ++index) {
3901 m = methods()->at(index);
3902 if (m->method_idnum() == idnum) {
3903 return m;
3904 }
3905 }
3906 // None found, return null for the caller to handle.
3907 return NULL;
3908 }
3909 return m;
3910 }
3911
3912
3913 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3914 if (idnum >= methods()->length()) {
3915 return NULL;
3916 }
3917 Method* m = methods()->at(idnum);
3918 if (m != NULL && m->orig_method_idnum() == idnum) {
3919 return m;
3920 }
3921 // Obsolete method idnum does not match the original idnum
3922 for (int index = 0; index < methods()->length(); ++index) {
3923 m = methods()->at(index);
3924 if (m->orig_method_idnum() == idnum) {
3925 return m;
3926 }
3927 }
3928 // None found, return null for the caller to handle.
3929 return NULL;
3930 }
3931
3932
3933 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3934 InstanceKlass* holder = get_klass_version(version);
3935 if (holder == NULL) {
3936 return NULL; // The version of klass is gone, no method is found
3937 }
3938 Method* method = holder->method_with_orig_idnum(idnum);
3939 return method;
3940 }
3941
3942 #if INCLUDE_JVMTI
3943 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3944 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3945 // Ignore the archived class stream data
3946 return NULL;
3947 } else {
3948 return _cached_class_file;
3949 }
3950 }
3951
3952 jint InstanceKlass::get_cached_class_file_len() {
3953 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3954 }
3955
3956 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3957 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3958 }
3959
3960 #if INCLUDE_CDS
3961 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3962 if (DumpSharedSpaces) {
3963 return _cached_class_file;
3964 } else {
3965 assert(this->is_shared(), "class should be shared");
3966 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3967 return _cached_class_file;
3968 } else {
3969 return NULL;
3970 }
3971 }
3972 }
3973 #endif
3974 #endif