1 /*
2 * Copyright (c) 1997, 2017, 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 "aot/aotLoader.hpp"
27 #include "classfile/classFileParser.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/javaClasses.hpp"
31 #include "classfile/moduleEntry.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/systemDictionaryShared.hpp"
34 #include "classfile/verifier.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "code/dependencyContext.hpp"
37 #include "compiler/compileBroker.hpp"
38 #include "gc/shared/collectedHeap.inline.hpp"
39 #include "gc/shared/specialized_oop_closures.hpp"
40 #include "interpreter/oopMapCache.hpp"
41 #include "interpreter/rewriter.hpp"
42 #include "jvmtifiles/jvmti.h"
43 #include "logging/log.hpp"
44 #include "logging/logMessage.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/heapInspection.hpp"
47 #include "memory/iterator.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.hpp"
50 #include "memory/metaspaceShared.hpp"
51 #include "memory/oopFactory.hpp"
52 #include "memory/resourceArea.hpp"
53 #include "oops/fieldStreams.hpp"
54 #include "oops/instanceClassLoaderKlass.hpp"
55 #include "oops/instanceKlass.inline.hpp"
56 #include "oops/instanceMirrorKlass.hpp"
57 #include "oops/instanceOop.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/method.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/symbol.hpp"
62 #include "prims/jvm.h"
63 #include "prims/jvmtiExport.hpp"
64 #include "prims/jvmtiRedefineClasses.hpp"
65 #include "prims/jvmtiThreadState.hpp"
66 #include "prims/methodComparator.hpp"
67 #include "runtime/atomic.hpp"
68 #include "runtime/fieldDescriptor.hpp"
69 #include "runtime/handles.inline.hpp"
70 #include "runtime/javaCalls.hpp"
71 #include "runtime/mutexLocker.hpp"
72 #include "runtime/orderAccess.inline.hpp"
73 #include "runtime/thread.inline.hpp"
74 #include "services/classLoadingService.hpp"
75 #include "services/threadService.hpp"
76 #include "utilities/dtrace.hpp"
77 #include "utilities/macros.hpp"
78 #include "utilities/stringUtils.hpp"
79 #ifdef COMPILER1
80 #include "c1/c1_Compiler.hpp"
81 #endif
82
83 #ifdef DTRACE_ENABLED
84
85
86 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
87 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
88 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
89 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
90 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
91 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
92 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
93 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
94 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
95 { \
96 char* data = NULL; \
97 int len = 0; \
98 Symbol* clss_name = name(); \
99 if (clss_name != NULL) { \
100 data = (char*)clss_name->bytes(); \
101 len = clss_name->utf8_length(); \
102 } \
103 HOTSPOT_CLASS_INITIALIZATION_##type( \
104 data, len, (void*)class_loader(), thread_type); \
105 }
106
107 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
108 { \
109 char* data = NULL; \
110 int len = 0; \
111 Symbol* clss_name = name(); \
112 if (clss_name != NULL) { \
113 data = (char*)clss_name->bytes(); \
114 len = clss_name->utf8_length(); \
115 } \
116 HOTSPOT_CLASS_INITIALIZATION_##type( \
117 data, len, (void*)class_loader(), thread_type, wait); \
118 }
119
120 #else // ndef DTRACE_ENABLED
121
122 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
123 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
124
125 #endif // ndef DTRACE_ENABLED
126
127 volatile int InstanceKlass::_total_instanceKlass_count = 0;
128
129 static inline bool is_class_loader(const Symbol* class_name,
130 const ClassFileParser& parser) {
131 assert(class_name != NULL, "invariant");
132
133 if (class_name == vmSymbols::java_lang_ClassLoader()) {
134 return true;
135 }
136
137 if (SystemDictionary::ClassLoader_klass_loaded()) {
138 const Klass* const super_klass = parser.super_klass();
139 if (super_klass != NULL) {
140 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
141 return true;
142 }
143 }
144 }
145 return false;
146 }
147
148 // called to verify that k is a member of this nest
149 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
150 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
151 if (log_is_enabled(Trace, class, nestmates)) {
152 ResourceMark rm(THREAD);
153 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
154 k->external_name(), this->external_name());
155 }
156 return false;
157 }
158
159 if (log_is_enabled(Trace, class, nestmates)) {
160 ResourceMark rm(THREAD);
161 log_trace(class, nestmates)("Checking nest membership of %s in %s",
162 k->external_name(), this->external_name());
163 }
164
165 // Check names first and if they match then check actual klass. This avoids
166 // resolving anything unnecessarily.
167 for (int i = 0; i < _nest_members->length(); i++) {
168 int cp_index = _nest_members->at(i);
169 Symbol* name = _constants->klass_name_at(cp_index);
170 if (name == k->name()) {
171 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
172
173 // names match so check actual klass - this may trigger class loading if
174 // it doesn't match (but that should be impossible)
175 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
176 if (k2 == k) {
177 log_trace(class, nestmates)("- class is listed as a nest member");
178 return true;
179 }
180 else {
181 // same name but different klass!
182 log_trace(class, nestmates)(" - klass comparison failed!");
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(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 of %s",
230 this->external_name());
231 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
232 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
233 }
234 // other exceptions pass through (OOME, StackOverflowError etc)
235 return NULL;
236 }
237
238 // A valid nest-host is an instance class in the current package that lists this
239 // class as a nest member. If any of these conditions are not met we simply throw
240 // IllegalAccessError, with a suitable message.
241
242 const char* error = NULL;
243
244 // Need to check we have an instance class first
245 if (k->is_instance_klass()) {
246 nest_host_k = InstanceKlass::cast(k);
247
248 // FIXME: an exception from this is perhaps impossible
249 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
250 if (is_member) {
251 // Finally check we're in the same package - as there could be collusion
252 // between untrusted types.
253 if (is_same_class_package(nest_host_k)) {
254 // save resolved nest-host value
255 _nest_host = nest_host_k;
256
257 if (log_is_enabled(Trace, class, nestmates)) {
258 ResourceMark rm(THREAD);
259 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
260 this->external_name(), k->external_name());
261 }
262 return nest_host_k;
263 }
264 else {
265 error = "types are in different packages";
266 }
267 }
268 else {
269 error = "current type is not listed as a nest member";
270 }
271 }
272 else {
273 error = "nest-host is not an instance class!";
274 }
275
276 if (log_is_enabled(Trace, class, nestmates)) {
277 ResourceMark rm(THREAD);
278 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
279 this->external_name(),
280 k->external_name(),
281 error);
282 }
283
284 ResourceMark rm(THREAD);
285 Exceptions::fthrow(THREAD_AND_LOCATION,
286 vmSymbols::java_lang_IllegalAccessError(),
287 "Type %s is not a nest member of %s: %s",
288 this->external_name(),
289 k->external_name(),
290 error
291 );
292 return NULL;
293 }
294 else {
295 if (log_is_enabled(Trace, class, nestmates)) {
296 ResourceMark rm(THREAD);
297 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
298 this->external_name());
299 }
300 // save resolved nest-host value
301 return (_nest_host = this);
302 }
303 }
304 return nest_host_k;
305 }
306
307 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
308 // or we are k's nest_host - all of which is covered by comparing the two
309 // resolved_nest_hosts
310 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
311
312 assert(this != k, "this should be handled by higher-level code");
313
314 // Per the JVMS we first resolve and validate the current class, then
315 // the target class k. Resolution exceptions will be passed on by upper
316 // layers. IllegalAccessErrors from membership validation failures will
317 // also be passed through.
318
319 InstanceKlass* cur_host = nest_host(THREAD);
320 if (cur_host == NULL || HAS_PENDING_EXCEPTION) {
321 return false;
322 }
323
324 Klass* k_nest_host = k->nest_host(THREAD);
325 if (k_nest_host == NULL || HAS_PENDING_EXCEPTION) {
326 return false;
327 }
328
329 bool access = (cur_host == k_nest_host);
330
331 if (log_is_enabled(Trace, class, nestmates)) {
332 ResourceMark rm(THREAD);
333 log_trace(class, nestmates)("Class %s does %shave nestmate accesss to %s",
334 this->external_name(),
335 access ? "" : "NOT ",
336 k->external_name());
337 }
338
339 return access;
340 }
341
342 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
343 const int size = InstanceKlass::size(parser.vtable_size(),
344 parser.itable_size(),
345 nonstatic_oop_map_size(parser.total_oop_map_count()),
346 parser.is_interface(),
347 parser.is_anonymous(),
348 should_store_fingerprint());
349
350 const Symbol* const class_name = parser.class_name();
351 assert(class_name != NULL, "invariant");
352 ClassLoaderData* loader_data = parser.loader_data();
353 assert(loader_data != NULL, "invariant");
354
355 InstanceKlass* ik;
356
357 // Allocation
358 if (REF_NONE == parser.reference_type()) {
359 if (class_name == vmSymbols::java_lang_Class()) {
360 // mirror
361 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
362 }
363 else if (is_class_loader(class_name, parser)) {
364 // class loader
365 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
366 }
367 else {
368 // normal
369 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
370 }
371 }
372 else {
373 // reference
374 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
375 }
376
377 // Check for pending exception before adding to the loader data and incrementing
378 // class count. Can get OOM here.
379 if (HAS_PENDING_EXCEPTION) {
380 return NULL;
381 }
382
383 assert(ik != NULL, "invariant");
384
385 const bool publicize = !parser.is_internal();
386
387 // Add all classes to our internal class loader list here,
388 // including classes in the bootstrap (NULL) class loader.
389 loader_data->add_class(ik, publicize);
390 Atomic::inc(&_total_instanceKlass_count);
391
392 return ik;
393 }
394
395
396 // copy method ordering from resource area to Metaspace
397 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
398 if (m != NULL) {
399 // allocate a new array and copy contents (memcpy?)
400 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
401 for (int i = 0; i < m->length(); i++) {
402 _method_ordering->at_put(i, m->at(i));
403 }
404 } else {
405 _method_ordering = Universe::the_empty_int_array();
406 }
407 }
408
409 // create a new array of vtable_indices for default methods
410 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
411 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
412 assert(default_vtable_indices() == NULL, "only create once");
413 set_default_vtable_indices(vtable_indices);
414 return vtable_indices;
415 }
416
417 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
418 _static_field_size(parser.static_field_size()),
419 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
420 _itable_len(parser.itable_size()),
421 _reference_type(parser.reference_type()),
422 _nest_members(NULL),
423 _nest_host_index(0),
424 _nest_host(NULL) {
425 set_vtable_length(parser.vtable_size());
426 set_kind(kind);
427 set_access_flags(parser.access_flags());
428 set_is_anonymous(parser.is_anonymous());
429 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
430 false));
431
432 assert(NULL == _methods, "underlying memory not zeroed?");
433 assert(is_instance_klass(), "is layout incorrect?");
434 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
435 }
436
437 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
438 Array<Method*>* methods) {
439 if (methods != NULL && methods != Universe::the_empty_method_array() &&
440 !methods->is_shared()) {
441 for (int i = 0; i < methods->length(); i++) {
442 Method* method = methods->at(i);
443 if (method == NULL) continue; // maybe null if error processing
444 // Only want to delete methods that are not executing for RedefineClasses.
445 // The previous version will point to them so they're not totally dangling
446 assert (!method->on_stack(), "shouldn't be called with methods on stack");
447 MetadataFactory::free_metadata(loader_data, method);
448 }
449 MetadataFactory::free_array<Method*>(loader_data, methods);
450 }
451 }
452
453 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
454 const Klass* super_klass,
455 Array<Klass*>* local_interfaces,
456 Array<Klass*>* transitive_interfaces) {
457 // Only deallocate transitive interfaces if not empty, same as super class
458 // or same as local interfaces. See code in parseClassFile.
459 Array<Klass*>* ti = transitive_interfaces;
460 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
461 // check that the interfaces don't come from super class
462 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
463 InstanceKlass::cast(super_klass)->transitive_interfaces();
464 if (ti != sti && ti != NULL && !ti->is_shared()) {
465 MetadataFactory::free_array<Klass*>(loader_data, ti);
466 }
467 }
468
469 // local interfaces can be empty
470 if (local_interfaces != Universe::the_empty_klass_array() &&
471 local_interfaces != NULL && !local_interfaces->is_shared()) {
472 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
473 }
474 }
475
476 // This function deallocates the metadata and C heap pointers that the
477 // InstanceKlass points to.
478 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
479
480 // Orphan the mirror first, CMS thinks it's still live.
481 if (java_mirror() != NULL) {
482 java_lang_Class::set_klass(java_mirror(), NULL);
483 }
484
485 // Need to take this class off the class loader data list.
486 loader_data->remove_class(this);
487
488 // The array_klass for this class is created later, after error handling.
489 // For class redefinition, we keep the original class so this scratch class
490 // doesn't have an array class. Either way, assert that there is nothing
491 // to deallocate.
492 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
493
494 // Release C heap allocated data that this might point to, which includes
495 // reference counting symbol names.
496 release_C_heap_structures();
497
498 deallocate_methods(loader_data, methods());
499 set_methods(NULL);
500
501 if (method_ordering() != NULL &&
502 method_ordering() != Universe::the_empty_int_array() &&
503 !method_ordering()->is_shared()) {
504 MetadataFactory::free_array<int>(loader_data, method_ordering());
505 }
506 set_method_ordering(NULL);
507
508 // default methods can be empty
509 if (default_methods() != NULL &&
510 default_methods() != Universe::the_empty_method_array() &&
511 !default_methods()->is_shared()) {
512 MetadataFactory::free_array<Method*>(loader_data, default_methods());
513 }
514 // Do NOT deallocate the default methods, they are owned by superinterfaces.
515 set_default_methods(NULL);
516
517 // default methods vtable indices can be empty
518 if (default_vtable_indices() != NULL &&
519 !default_vtable_indices()->is_shared()) {
520 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
521 }
522 set_default_vtable_indices(NULL);
523
524
525 // This array is in Klass, but remove it with the InstanceKlass since
526 // this place would be the only caller and it can share memory with transitive
527 // interfaces.
528 if (secondary_supers() != NULL &&
529 secondary_supers() != Universe::the_empty_klass_array() &&
530 secondary_supers() != transitive_interfaces() &&
531 !secondary_supers()->is_shared()) {
532 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
533 }
534 set_secondary_supers(NULL);
535
536 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
537 set_transitive_interfaces(NULL);
538 set_local_interfaces(NULL);
539
540 if (fields() != NULL && !fields()->is_shared()) {
541 MetadataFactory::free_array<jushort>(loader_data, fields());
542 }
543 set_fields(NULL, 0);
544
545 // If a method from a redefined class is using this constant pool, don't
546 // delete it, yet. The new class's previous version will point to this.
547 if (constants() != NULL) {
548 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
549 if (!constants()->is_shared()) {
550 MetadataFactory::free_metadata(loader_data, constants());
551 }
552 // Delete any cached resolution errors for the constant pool
553 SystemDictionary::delete_resolution_error(constants());
554
555 set_constants(NULL);
556 }
557
558 if (inner_classes() != NULL &&
559 inner_classes() != Universe::the_empty_short_array() &&
560 !inner_classes()->is_shared()) {
561 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
562 }
563 set_inner_classes(NULL);
564
565 if (nest_members() != NULL &&
566 nest_members() != Universe::the_empty_short_array() &&
567 !nest_members()->is_shared()) {
568 MetadataFactory::free_array<jushort>(loader_data, nest_members());
569 }
570 set_nest_members(NULL);
571
572 // We should deallocate the Annotations instance if it's not in shared spaces.
573 if (annotations() != NULL && !annotations()->is_shared()) {
574 MetadataFactory::free_metadata(loader_data, annotations());
575 }
576 set_annotations(NULL);
577 }
578
579 bool InstanceKlass::should_be_initialized() const {
580 return !is_initialized();
581 }
582
583 klassItable InstanceKlass::itable() const {
584 return klassItable(const_cast<InstanceKlass*>(this));
585 }
586
587 void InstanceKlass::eager_initialize(Thread *thread) {
588 if (!EagerInitialization) return;
589
590 if (this->is_not_initialized()) {
591 // abort if the the class has a class initializer
592 if (this->class_initializer() != NULL) return;
593
594 // abort if it is java.lang.Object (initialization is handled in genesis)
595 Klass* super_klass = super();
596 if (super_klass == NULL) return;
597
598 // abort if the super class should be initialized
599 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
600
601 // call body to expose the this pointer
602 eager_initialize_impl();
603 }
604 }
605
606 // JVMTI spec thinks there are signers and protection domain in the
607 // instanceKlass. These accessors pretend these fields are there.
608 // The hprof specification also thinks these fields are in InstanceKlass.
609 oop InstanceKlass::protection_domain() const {
610 // return the protection_domain from the mirror
611 return java_lang_Class::protection_domain(java_mirror());
612 }
613
614 // To remove these from requires an incompatible change and CCC request.
615 objArrayOop InstanceKlass::signers() const {
616 // return the signers from the mirror
617 return java_lang_Class::signers(java_mirror());
618 }
619
620 oop InstanceKlass::init_lock() const {
621 // return the init lock from the mirror
622 oop lock = java_lang_Class::init_lock(java_mirror());
623 // Prevent reordering with any access of initialization state
624 OrderAccess::loadload();
625 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
626 "only fully initialized state can have a null lock");
627 return lock;
628 }
629
630 // Set the initialization lock to null so the object can be GC'ed. Any racing
631 // threads to get this lock will see a null lock and will not lock.
632 // That's okay because they all check for initialized state after getting
633 // the lock and return.
634 void InstanceKlass::fence_and_clear_init_lock() {
635 // make sure previous stores are all done, notably the init_state.
636 OrderAccess::storestore();
637 java_lang_Class::set_init_lock(java_mirror(), NULL);
638 assert(!is_not_initialized(), "class must be initialized now");
639 }
640
641 void InstanceKlass::eager_initialize_impl() {
642 EXCEPTION_MARK;
643 HandleMark hm(THREAD);
644 Handle h_init_lock(THREAD, init_lock());
645 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
646
647 // abort if someone beat us to the initialization
648 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
649
650 ClassState old_state = init_state();
651 link_class_impl(true, THREAD);
652 if (HAS_PENDING_EXCEPTION) {
653 CLEAR_PENDING_EXCEPTION;
654 // Abort if linking the class throws an exception.
655
656 // Use a test to avoid redundantly resetting the state if there's
657 // no change. Set_init_state() asserts that state changes make
658 // progress, whereas here we might just be spinning in place.
659 if (old_state != _init_state)
660 set_init_state(old_state);
661 } else {
662 // linking successfull, mark class as initialized
663 set_init_state(fully_initialized);
664 fence_and_clear_init_lock();
665 // trace
666 if (log_is_enabled(Info, class, init)) {
667 ResourceMark rm(THREAD);
668 log_info(class, init)("[Initialized %s without side effects]", external_name());
669 }
670 }
671 }
672
673
674 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
675 // process. The step comments refers to the procedure described in that section.
676 // Note: implementation moved to static method to expose the this pointer.
677 void InstanceKlass::initialize(TRAPS) {
678 if (this->should_be_initialized()) {
679 initialize_impl(CHECK);
680 // Note: at this point the class may be initialized
681 // OR it may be in the state of being initialized
682 // in case of recursive initialization!
683 } else {
684 assert(is_initialized(), "sanity check");
685 }
686 }
687
688
689 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
690 // 1) Verify the bytecodes
691 Verifier::Mode mode =
692 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
693 return Verifier::verify(this, mode, should_verify_class(), THREAD);
694 }
695
696
697 // Used exclusively by the shared spaces dump mechanism to prevent
698 // classes mapped into the shared regions in new VMs from appearing linked.
699
700 void InstanceKlass::unlink_class() {
701 assert(is_linked(), "must be linked");
702 _init_state = loaded;
703 }
704
705 void InstanceKlass::link_class(TRAPS) {
706 assert(is_loaded(), "must be loaded");
707 if (!is_linked()) {
708 link_class_impl(true, CHECK);
709 }
710 }
711
712 // Called to verify that a class can link during initialization, without
713 // throwing a VerifyError.
714 bool InstanceKlass::link_class_or_fail(TRAPS) {
715 assert(is_loaded(), "must be loaded");
716 if (!is_linked()) {
717 link_class_impl(false, CHECK_false);
718 }
719 return is_linked();
720 }
721
722 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
723 if (DumpSharedSpaces && is_in_error_state()) {
724 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
725 // the class has failed verification. Throwing the NoClassDefFoundError here is just
726 // a convenient way to stop repeat attempts to verify the same (bad) class.
727 //
728 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
729 // if we are executing Java code. This is not a problem for CDS dumping phase since
730 // it doesn't execute any Java code.
731 ResourceMark rm(THREAD);
732 Exceptions::fthrow(THREAD_AND_LOCATION,
733 vmSymbols::java_lang_NoClassDefFoundError(),
734 "Class %s, or one of its supertypes, failed class initialization",
735 external_name());
736 return false;
737 }
738 // return if already verified
739 if (is_linked()) {
740 return true;
741 }
742
743 // Timing
744 // timer handles recursion
745 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
746 JavaThread* jt = (JavaThread*)THREAD;
747
748 // link super class before linking this class
749 Klass* super_klass = super();
750 if (super_klass != NULL) {
751 if (super_klass->is_interface()) { // check if super class is an interface
752 ResourceMark rm(THREAD);
753 Exceptions::fthrow(
754 THREAD_AND_LOCATION,
755 vmSymbols::java_lang_IncompatibleClassChangeError(),
756 "class %s has interface %s as super class",
757 external_name(),
758 super_klass->external_name()
759 );
760 return false;
761 }
762
763 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
764 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
765 }
766
767 // link all interfaces implemented by this class before linking this class
768 Array<Klass*>* interfaces = local_interfaces();
769 int num_interfaces = interfaces->length();
770 for (int index = 0; index < num_interfaces; index++) {
771 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
772 interk->link_class_impl(throw_verifyerror, CHECK_false);
773 }
774
775 // in case the class is linked in the process of linking its superclasses
776 if (is_linked()) {
777 return true;
778 }
779
780 // trace only the link time for this klass that includes
781 // the verification time
782 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
783 ClassLoader::perf_class_link_selftime(),
784 ClassLoader::perf_classes_linked(),
785 jt->get_thread_stat()->perf_recursion_counts_addr(),
786 jt->get_thread_stat()->perf_timers_addr(),
787 PerfClassTraceTime::CLASS_LINK);
788
789 // verification & rewriting
790 {
791 HandleMark hm(THREAD);
792 Handle h_init_lock(THREAD, init_lock());
793 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
794 // rewritten will have been set if loader constraint error found
795 // on an earlier link attempt
796 // don't verify or rewrite if already rewritten
797 //
798
799 if (!is_linked()) {
800 if (!is_rewritten()) {
801 {
802 bool verify_ok = verify_code(throw_verifyerror, THREAD);
803 if (!verify_ok) {
804 return false;
805 }
806 }
807
808 // Just in case a side-effect of verify linked this class already
809 // (which can sometimes happen since the verifier loads classes
810 // using custom class loaders, which are free to initialize things)
811 if (is_linked()) {
812 return true;
813 }
814
815 // also sets rewritten
816 rewrite_class(CHECK_false);
817 } else if (is_shared()) {
818 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
819 }
820
821 // relocate jsrs and link methods after they are all rewritten
822 link_methods(CHECK_false);
823
824 // Initialize the vtable and interface table after
825 // methods have been rewritten since rewrite may
826 // fabricate new Method*s.
827 // also does loader constraint checking
828 //
829 // initialize_vtable and initialize_itable need to be rerun for
830 // a shared class if the class is not loaded by the NULL classloader.
831 ClassLoaderData * loader_data = class_loader_data();
832 if (!(is_shared() &&
833 loader_data->is_the_null_class_loader_data())) {
834 ResourceMark rm(THREAD);
835 vtable().initialize_vtable(true, CHECK_false);
836 itable().initialize_itable(true, CHECK_false);
837 }
838 #ifdef ASSERT
839 else {
840 vtable().verify(tty, true);
841 // In case itable verification is ever added.
842 // itable().verify(tty, true);
843 }
844 #endif
845 set_init_state(linked);
846 if (JvmtiExport::should_post_class_prepare()) {
847 Thread *thread = THREAD;
848 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
849 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
850 }
851 }
852 }
853 return true;
854 }
855
856 // Rewrite the byte codes of all of the methods of a class.
857 // The rewriter must be called exactly once. Rewriting must happen after
858 // verification but before the first method of the class is executed.
859 void InstanceKlass::rewrite_class(TRAPS) {
860 assert(is_loaded(), "must be loaded");
861 if (is_rewritten()) {
862 assert(is_shared(), "rewriting an unshared class?");
863 return;
864 }
865 Rewriter::rewrite(this, CHECK);
866 set_rewritten();
867 }
868
869 // Now relocate and link method entry points after class is rewritten.
870 // This is outside is_rewritten flag. In case of an exception, it can be
871 // executed more than once.
872 void InstanceKlass::link_methods(TRAPS) {
873 int len = methods()->length();
874 for (int i = len-1; i >= 0; i--) {
875 methodHandle m(THREAD, methods()->at(i));
876
877 // Set up method entry points for compiler and interpreter .
878 m->link_method(m, CHECK);
879 }
880 }
881
882 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
883 void InstanceKlass::initialize_super_interfaces(TRAPS) {
884 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
885 for (int i = 0; i < local_interfaces()->length(); ++i) {
886 Klass* iface = local_interfaces()->at(i);
887 InstanceKlass* ik = InstanceKlass::cast(iface);
888
889 // Initialization is depth first search ie. we start with top of the inheritance tree
890 // has_nonstatic_concrete_methods drives searching superinterfaces since it
891 // means has_nonstatic_concrete_methods in its superinterface hierarchy
892 if (ik->has_nonstatic_concrete_methods()) {
893 ik->initialize_super_interfaces(CHECK);
894 }
895
896 // Only initialize() interfaces that "declare" concrete methods.
897 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
898 ik->initialize(CHECK);
899 }
900 }
901 }
902
903 void InstanceKlass::initialize_impl(TRAPS) {
904 HandleMark hm(THREAD);
905
906 // Make sure klass is linked (verified) before initialization
907 // A class could already be verified, since it has been reflected upon.
908 link_class(CHECK);
909
910 DTRACE_CLASSINIT_PROBE(required, -1);
911
912 bool wait = false;
913
914 // refer to the JVM book page 47 for description of steps
915 // Step 1
916 {
917 Handle h_init_lock(THREAD, init_lock());
918 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
919
920 Thread *self = THREAD; // it's passed the current thread
921
922 // Step 2
923 // If we were to use wait() instead of waitInterruptibly() then
924 // we might end up throwing IE from link/symbol resolution sites
925 // that aren't expected to throw. This would wreak havoc. See 6320309.
926 while(is_being_initialized() && !is_reentrant_initialization(self)) {
927 wait = true;
928 ol.waitUninterruptibly(CHECK);
929 }
930
931 // Step 3
932 if (is_being_initialized() && is_reentrant_initialization(self)) {
933 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
934 return;
935 }
936
937 // Step 4
938 if (is_initialized()) {
939 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
940 return;
941 }
942
943 // Step 5
944 if (is_in_error_state()) {
945 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
946 ResourceMark rm(THREAD);
947 const char* desc = "Could not initialize class ";
948 const char* className = external_name();
949 size_t msglen = strlen(desc) + strlen(className) + 1;
950 char* message = NEW_RESOURCE_ARRAY(char, msglen);
951 if (NULL == message) {
952 // Out of memory: can't create detailed error message
953 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
954 } else {
955 jio_snprintf(message, msglen, "%s%s", desc, className);
956 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
957 }
958 }
959
960 // Step 6
961 set_init_state(being_initialized);
962 set_init_thread(self);
963 }
964
965 // Step 7
966 // Next, if C is a class rather than an interface, initialize it's super class and super
967 // interfaces.
968 if (!is_interface()) {
969 Klass* super_klass = super();
970 if (super_klass != NULL && super_klass->should_be_initialized()) {
971 super_klass->initialize(THREAD);
972 }
973 // If C implements any interface that declares a non-static, concrete method,
974 // the initialization of C triggers initialization of its super interfaces.
975 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
976 // having a superinterface that declares, non-static, concrete methods
977 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
978 initialize_super_interfaces(THREAD);
979 }
980
981 // If any exceptions, complete abruptly, throwing the same exception as above.
982 if (HAS_PENDING_EXCEPTION) {
983 Handle e(THREAD, PENDING_EXCEPTION);
984 CLEAR_PENDING_EXCEPTION;
985 {
986 EXCEPTION_MARK;
987 // Locks object, set state, and notify all waiting threads
988 set_initialization_state_and_notify(initialization_error, THREAD);
989 CLEAR_PENDING_EXCEPTION;
990 }
991 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
992 THROW_OOP(e());
993 }
994 }
995
996
997 // Look for aot compiled methods for this klass, including class initializer.
998 AOTLoader::load_for_klass(this, THREAD);
999
1000 // Step 8
1001 {
1002 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
1003 JavaThread* jt = (JavaThread*)THREAD;
1004 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1005 // Timer includes any side effects of class initialization (resolution,
1006 // etc), but not recursive entry into call_class_initializer().
1007 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1008 ClassLoader::perf_class_init_selftime(),
1009 ClassLoader::perf_classes_inited(),
1010 jt->get_thread_stat()->perf_recursion_counts_addr(),
1011 jt->get_thread_stat()->perf_timers_addr(),
1012 PerfClassTraceTime::CLASS_CLINIT);
1013 call_class_initializer(THREAD);
1014 }
1015
1016 // Step 9
1017 if (!HAS_PENDING_EXCEPTION) {
1018 set_initialization_state_and_notify(fully_initialized, CHECK);
1019 {
1020 debug_only(vtable().verify(tty, true);)
1021 }
1022 }
1023 else {
1024 // Step 10 and 11
1025 Handle e(THREAD, PENDING_EXCEPTION);
1026 CLEAR_PENDING_EXCEPTION;
1027 // JVMTI has already reported the pending exception
1028 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1029 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1030 {
1031 EXCEPTION_MARK;
1032 set_initialization_state_and_notify(initialization_error, THREAD);
1033 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1034 // JVMTI has already reported the pending exception
1035 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1036 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1037 }
1038 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1039 if (e->is_a(SystemDictionary::Error_klass())) {
1040 THROW_OOP(e());
1041 } else {
1042 JavaCallArguments args(e);
1043 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1044 vmSymbols::throwable_void_signature(),
1045 &args);
1046 }
1047 }
1048 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1049 }
1050
1051
1052 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1053 Handle h_init_lock(THREAD, init_lock());
1054 if (h_init_lock() != NULL) {
1055 ObjectLocker ol(h_init_lock, THREAD);
1056 set_init_state(state);
1057 fence_and_clear_init_lock();
1058 ol.notify_all(CHECK);
1059 } else {
1060 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1061 set_init_state(state);
1062 }
1063 }
1064
1065 // The embedded _implementor field can only record one implementor.
1066 // When there are more than one implementors, the _implementor field
1067 // is set to the interface Klass* itself. Following are the possible
1068 // values for the _implementor field:
1069 // NULL - no implementor
1070 // implementor Klass* - one implementor
1071 // self - more than one implementor
1072 //
1073 // The _implementor field only exists for interfaces.
1074 void InstanceKlass::add_implementor(Klass* k) {
1075 assert(Compile_lock->owned_by_self(), "");
1076 assert(is_interface(), "not interface");
1077 // Filter out my subinterfaces.
1078 // (Note: Interfaces are never on the subklass list.)
1079 if (InstanceKlass::cast(k)->is_interface()) return;
1080
1081 // Filter out subclasses whose supers already implement me.
1082 // (Note: CHA must walk subclasses of direct implementors
1083 // in order to locate indirect implementors.)
1084 Klass* sk = k->super();
1085 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1086 // We only need to check one immediate superclass, since the
1087 // implements_interface query looks at transitive_interfaces.
1088 // Any supers of the super have the same (or fewer) transitive_interfaces.
1089 return;
1090
1091 Klass* ik = implementor();
1092 if (ik == NULL) {
1093 set_implementor(k);
1094 } else if (ik != this) {
1095 // There is already an implementor. Use itself as an indicator of
1096 // more than one implementors.
1097 set_implementor(this);
1098 }
1099
1100 // The implementor also implements the transitive_interfaces
1101 for (int index = 0; index < local_interfaces()->length(); index++) {
1102 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1103 }
1104 }
1105
1106 void InstanceKlass::init_implementor() {
1107 if (is_interface()) {
1108 set_implementor(NULL);
1109 }
1110 }
1111
1112
1113 void InstanceKlass::process_interfaces(Thread *thread) {
1114 // link this class into the implementors list of every interface it implements
1115 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1116 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1117 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1118 assert(interf->is_interface(), "expected interface");
1119 interf->add_implementor(this);
1120 }
1121 }
1122
1123 bool InstanceKlass::can_be_primary_super_slow() const {
1124 if (is_interface())
1125 return false;
1126 else
1127 return Klass::can_be_primary_super_slow();
1128 }
1129
1130 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1131 // The secondaries are the implemented interfaces.
1132 Array<Klass*>* interfaces = transitive_interfaces();
1133 int num_secondaries = num_extra_slots + interfaces->length();
1134 if (num_secondaries == 0) {
1135 // Must share this for correct bootstrapping!
1136 set_secondary_supers(Universe::the_empty_klass_array());
1137 return NULL;
1138 } else if (num_extra_slots == 0) {
1139 // The secondary super list is exactly the same as the transitive interfaces.
1140 // Redefine classes has to be careful not to delete this!
1141 set_secondary_supers(interfaces);
1142 return NULL;
1143 } else {
1144 // Copy transitive interfaces to a temporary growable array to be constructed
1145 // into the secondary super list with extra slots.
1146 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1147 for (int i = 0; i < interfaces->length(); i++) {
1148 secondaries->push(interfaces->at(i));
1149 }
1150 return secondaries;
1151 }
1152 }
1153
1154 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1155 if (k->is_interface()) {
1156 return implements_interface(k);
1157 } else {
1158 return Klass::compute_is_subtype_of(k);
1159 }
1160 }
1161
1162 bool InstanceKlass::implements_interface(Klass* k) const {
1163 if (this == k) return true;
1164 assert(k->is_interface(), "should be an interface class");
1165 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1166 if (transitive_interfaces()->at(i) == k) {
1167 return true;
1168 }
1169 }
1170 return false;
1171 }
1172
1173 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1174 // Verify direct super interface
1175 if (this == k) return true;
1176 assert(k->is_interface(), "should be an interface class");
1177 for (int i = 0; i < local_interfaces()->length(); i++) {
1178 if (local_interfaces()->at(i) == k) {
1179 return true;
1180 }
1181 }
1182 return false;
1183 }
1184
1185 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1186 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1187 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1188 report_java_out_of_memory("Requested array size exceeds VM limit");
1189 JvmtiExport::post_array_size_exhausted();
1190 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1191 }
1192 int size = objArrayOopDesc::object_size(length);
1193 Klass* ak = array_klass(n, CHECK_NULL);
1194 objArrayOop o =
1195 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1196 return o;
1197 }
1198
1199 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1200 if (TraceFinalizerRegistration) {
1201 tty->print("Registered ");
1202 i->print_value_on(tty);
1203 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1204 }
1205 instanceHandle h_i(THREAD, i);
1206 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1207 JavaValue result(T_VOID);
1208 JavaCallArguments args(h_i);
1209 methodHandle mh (THREAD, Universe::finalizer_register_method());
1210 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1211 return h_i();
1212 }
1213
1214 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1215 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1216 int size = size_helper(); // Query before forming handle.
1217
1218 instanceOop i;
1219
1220 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1221 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1222 i = register_finalizer(i, CHECK_NULL);
1223 }
1224 return i;
1225 }
1226
1227 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1228 if (is_interface() || is_abstract()) {
1229 ResourceMark rm(THREAD);
1230 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1231 : vmSymbols::java_lang_InstantiationException(), external_name());
1232 }
1233 if (this == SystemDictionary::Class_klass()) {
1234 ResourceMark rm(THREAD);
1235 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1236 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1237 }
1238 }
1239
1240 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1241 // Need load-acquire for lock-free read
1242 if (array_klasses_acquire() == NULL) {
1243 if (or_null) return NULL;
1244
1245 ResourceMark rm;
1246 JavaThread *jt = (JavaThread *)THREAD;
1247 {
1248 // Atomic creation of array_klasses
1249 MutexLocker mc(Compile_lock, THREAD); // for vtables
1250 MutexLocker ma(MultiArray_lock, THREAD);
1251
1252 // Check if update has already taken place
1253 if (array_klasses() == NULL) {
1254 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1255 // use 'release' to pair with lock-free load
1256 release_set_array_klasses(k);
1257 }
1258 }
1259 }
1260 // _this will always be set at this point
1261 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1262 if (or_null) {
1263 return oak->array_klass_or_null(n);
1264 }
1265 return oak->array_klass(n, THREAD);
1266 }
1267
1268 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1269 return array_klass_impl(or_null, 1, THREAD);
1270 }
1271
1272 static int call_class_initializer_counter = 0; // for debugging
1273
1274 Method* InstanceKlass::class_initializer() const {
1275 Method* clinit = find_method(
1276 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1277 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1278 return clinit;
1279 }
1280 return NULL;
1281 }
1282
1283 void InstanceKlass::call_class_initializer(TRAPS) {
1284 if (ReplayCompiles &&
1285 (ReplaySuppressInitializers == 1 ||
1286 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1287 // Hide the existence of the initializer for the purpose of replaying the compile
1288 return;
1289 }
1290
1291 methodHandle h_method(THREAD, class_initializer());
1292 assert(!is_initialized(), "we cannot initialize twice");
1293 LogTarget(Info, class, init) lt;
1294 if (lt.is_enabled()) {
1295 ResourceMark rm;
1296 LogStream ls(lt);
1297 ls.print("%d Initializing ", call_class_initializer_counter++);
1298 name()->print_value_on(&ls);
1299 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1300 }
1301 if (h_method() != NULL) {
1302 JavaCallArguments args; // No arguments
1303 JavaValue result(T_VOID);
1304 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1305 }
1306 }
1307
1308
1309 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1310 InterpreterOopMap* entry_for) {
1311 // Lazily create the _oop_map_cache at first request
1312 // Lock-free access requires load_ptr_acquire.
1313 OopMapCache* oop_map_cache =
1314 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache));
1315 if (oop_map_cache == NULL) {
1316 MutexLocker x(OopMapCacheAlloc_lock);
1317 // Check if _oop_map_cache was allocated while we were waiting for this lock
1318 if ((oop_map_cache = _oop_map_cache) == NULL) {
1319 oop_map_cache = new OopMapCache();
1320 // Ensure _oop_map_cache is stable, since it is examined without a lock
1321 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache);
1322 }
1323 }
1324 // _oop_map_cache is constant after init; lookup below does its own locking.
1325 oop_map_cache->lookup(method, bci, entry_for);
1326 }
1327
1328
1329 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1330 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1331 Symbol* f_name = fs.name();
1332 Symbol* f_sig = fs.signature();
1333 if (f_name == name && f_sig == sig) {
1334 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1335 return true;
1336 }
1337 }
1338 return false;
1339 }
1340
1341
1342 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1343 const int n = local_interfaces()->length();
1344 for (int i = 0; i < n; i++) {
1345 Klass* intf1 = local_interfaces()->at(i);
1346 assert(intf1->is_interface(), "just checking type");
1347 // search for field in current interface
1348 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1349 assert(fd->is_static(), "interface field must be static");
1350 return intf1;
1351 }
1352 // search for field in direct superinterfaces
1353 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1354 if (intf2 != NULL) return intf2;
1355 }
1356 // otherwise field lookup fails
1357 return NULL;
1358 }
1359
1360
1361 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1362 // search order according to newest JVM spec (5.4.3.2, p.167).
1363 // 1) search for field in current klass
1364 if (find_local_field(name, sig, fd)) {
1365 return const_cast<InstanceKlass*>(this);
1366 }
1367 // 2) search for field recursively in direct superinterfaces
1368 { Klass* intf = find_interface_field(name, sig, fd);
1369 if (intf != NULL) return intf;
1370 }
1371 // 3) apply field lookup recursively if superclass exists
1372 { Klass* supr = super();
1373 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1374 }
1375 // 4) otherwise field lookup fails
1376 return NULL;
1377 }
1378
1379
1380 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1381 // search order according to newest JVM spec (5.4.3.2, p.167).
1382 // 1) search for field in current klass
1383 if (find_local_field(name, sig, fd)) {
1384 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1385 }
1386 // 2) search for field recursively in direct superinterfaces
1387 if (is_static) {
1388 Klass* intf = find_interface_field(name, sig, fd);
1389 if (intf != NULL) return intf;
1390 }
1391 // 3) apply field lookup recursively if superclass exists
1392 { Klass* supr = super();
1393 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1394 }
1395 // 4) otherwise field lookup fails
1396 return NULL;
1397 }
1398
1399
1400 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1401 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1402 if (fs.offset() == offset) {
1403 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1404 if (fd->is_static() == is_static) return true;
1405 }
1406 }
1407 return false;
1408 }
1409
1410
1411 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1412 Klass* klass = const_cast<InstanceKlass*>(this);
1413 while (klass != NULL) {
1414 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1415 return true;
1416 }
1417 klass = klass->super();
1418 }
1419 return false;
1420 }
1421
1422
1423 void InstanceKlass::methods_do(void f(Method* method)) {
1424 // Methods aren't stable until they are loaded. This can be read outside
1425 // a lock through the ClassLoaderData for profiling
1426 if (!is_loaded()) {
1427 return;
1428 }
1429
1430 int len = methods()->length();
1431 for (int index = 0; index < len; index++) {
1432 Method* m = methods()->at(index);
1433 assert(m->is_method(), "must be method");
1434 f(m);
1435 }
1436 }
1437
1438
1439 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1440 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1441 if (fs.access_flags().is_static()) {
1442 fieldDescriptor& fd = fs.field_descriptor();
1443 cl->do_field(&fd);
1444 }
1445 }
1446 }
1447
1448
1449 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1450 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1451 if (fs.access_flags().is_static()) {
1452 fieldDescriptor& fd = fs.field_descriptor();
1453 f(&fd, mirror, CHECK);
1454 }
1455 }
1456 }
1457
1458
1459 static int compare_fields_by_offset(int* a, int* b) {
1460 return a[0] - b[0];
1461 }
1462
1463 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1464 InstanceKlass* super = superklass();
1465 if (super != NULL) {
1466 super->do_nonstatic_fields(cl);
1467 }
1468 fieldDescriptor fd;
1469 int length = java_fields_count();
1470 // In DebugInfo nonstatic fields are sorted by offset.
1471 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1472 int j = 0;
1473 for (int i = 0; i < length; i += 1) {
1474 fd.reinitialize(this, i);
1475 if (!fd.is_static()) {
1476 fields_sorted[j + 0] = fd.offset();
1477 fields_sorted[j + 1] = i;
1478 j += 2;
1479 }
1480 }
1481 if (j > 0) {
1482 length = j;
1483 // _sort_Fn is defined in growableArray.hpp.
1484 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1485 for (int i = 0; i < length; i += 2) {
1486 fd.reinitialize(this, fields_sorted[i + 1]);
1487 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1488 cl->do_field(&fd);
1489 }
1490 }
1491 FREE_C_HEAP_ARRAY(int, fields_sorted);
1492 }
1493
1494
1495 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1496 if (array_klasses() != NULL)
1497 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1498 }
1499
1500 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1501 if (array_klasses() != NULL)
1502 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1503 }
1504
1505 #ifdef ASSERT
1506 static int linear_search(const Array<Method*>* methods,
1507 const Symbol* name,
1508 const Symbol* signature) {
1509 const int len = methods->length();
1510 for (int index = 0; index < len; index++) {
1511 const Method* const m = methods->at(index);
1512 assert(m->is_method(), "must be method");
1513 if (m->signature() == signature && m->name() == name) {
1514 return index;
1515 }
1516 }
1517 return -1;
1518 }
1519 #endif
1520
1521 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1522 int len = methods->length();
1523 // methods are sorted, so do binary search
1524 int l = 0;
1525 int h = len - 1;
1526 while (l <= h) {
1527 int mid = (l + h) >> 1;
1528 Method* m = methods->at(mid);
1529 assert(m->is_method(), "must be method");
1530 int res = m->name()->fast_compare(name);
1531 if (res == 0) {
1532 return mid;
1533 } else if (res < 0) {
1534 l = mid + 1;
1535 } else {
1536 h = mid - 1;
1537 }
1538 }
1539 return -1;
1540 }
1541
1542 // find_method looks up the name/signature in the local methods array
1543 Method* InstanceKlass::find_method(const Symbol* name,
1544 const Symbol* signature) const {
1545 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1546 }
1547
1548 Method* InstanceKlass::find_method_impl(const Symbol* name,
1549 const Symbol* signature,
1550 OverpassLookupMode overpass_mode,
1551 StaticLookupMode static_mode,
1552 PrivateLookupMode private_mode) const {
1553 return InstanceKlass::find_method_impl(methods(),
1554 name,
1555 signature,
1556 overpass_mode,
1557 static_mode,
1558 private_mode);
1559 }
1560
1561 // find_instance_method looks up the name/signature in the local methods array
1562 // and skips over static methods
1563 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1564 const Symbol* name,
1565 const Symbol* signature) {
1566 Method* const meth = InstanceKlass::find_method_impl(methods,
1567 name,
1568 signature,
1569 find_overpass,
1570 skip_static,
1571 find_private);
1572 assert(((meth == NULL) || !meth->is_static()),
1573 "find_instance_method should have skipped statics");
1574 return meth;
1575 }
1576
1577 // find_instance_method looks up the name/signature in the local methods array
1578 // and skips over static methods
1579 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1580 return InstanceKlass::find_instance_method(methods(), name, signature);
1581 }
1582
1583 // Find looks up the name/signature in the local methods array
1584 // and filters on the overpass, static and private flags
1585 // This returns the first one found
1586 // note that the local methods array can have up to one overpass, one static
1587 // and one instance (private or not) with the same name/signature
1588 Method* InstanceKlass::find_local_method(const Symbol* name,
1589 const Symbol* signature,
1590 OverpassLookupMode overpass_mode,
1591 StaticLookupMode static_mode,
1592 PrivateLookupMode private_mode) const {
1593 return InstanceKlass::find_method_impl(methods(),
1594 name,
1595 signature,
1596 overpass_mode,
1597 static_mode,
1598 private_mode);
1599 }
1600
1601 // Find looks up the name/signature in the local methods array
1602 // and filters on the overpass, static and private flags
1603 // This returns the first one found
1604 // note that the local methods array can have up to one overpass, one static
1605 // and one instance (private or not) with the same name/signature
1606 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1607 const Symbol* name,
1608 const Symbol* signature,
1609 OverpassLookupMode overpass_mode,
1610 StaticLookupMode static_mode,
1611 PrivateLookupMode private_mode) {
1612 return InstanceKlass::find_method_impl(methods,
1613 name,
1614 signature,
1615 overpass_mode,
1616 static_mode,
1617 private_mode);
1618 }
1619
1620 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1621 const Symbol* name,
1622 const Symbol* signature) {
1623 return InstanceKlass::find_method_impl(methods,
1624 name,
1625 signature,
1626 find_overpass,
1627 find_static,
1628 find_private);
1629 }
1630
1631 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1632 const Symbol* name,
1633 const Symbol* signature,
1634 OverpassLookupMode overpass_mode,
1635 StaticLookupMode static_mode,
1636 PrivateLookupMode private_mode) {
1637 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1638 return hit >= 0 ? methods->at(hit): NULL;
1639 }
1640
1641 // true if method matches signature and conforms to skipping_X conditions.
1642 static bool method_matches(const Method* m,
1643 const Symbol* signature,
1644 bool skipping_overpass,
1645 bool skipping_static,
1646 bool skipping_private) {
1647 return ((m->signature() == signature) &&
1648 (!skipping_overpass || !m->is_overpass()) &&
1649 (!skipping_static || !m->is_static()) &&
1650 (!skipping_private || !m->is_private()));
1651 }
1652
1653 // Used directly for default_methods to find the index into the
1654 // default_vtable_indices, and indirectly by find_method
1655 // find_method_index looks in the local methods array to return the index
1656 // of the matching name/signature. If, overpass methods are being ignored,
1657 // the search continues to find a potential non-overpass match. This capability
1658 // is important during method resolution to prefer a static method, for example,
1659 // over an overpass method.
1660 // There is the possibility in any _method's array to have the same name/signature
1661 // for a static method, an overpass method and a local instance method
1662 // To correctly catch a given method, the search criteria may need
1663 // to explicitly skip the other two. For local instance methods, it
1664 // is often necessary to skip private methods
1665 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1666 const Symbol* name,
1667 const Symbol* signature,
1668 OverpassLookupMode overpass_mode,
1669 StaticLookupMode static_mode,
1670 PrivateLookupMode private_mode) {
1671 const bool skipping_overpass = (overpass_mode == skip_overpass);
1672 const bool skipping_static = (static_mode == skip_static);
1673 const bool skipping_private = (private_mode == skip_private);
1674 const int hit = binary_search(methods, name);
1675 if (hit != -1) {
1676 const Method* const m = methods->at(hit);
1677
1678 // Do linear search to find matching signature. First, quick check
1679 // for common case, ignoring overpasses if requested.
1680 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1681 return hit;
1682 }
1683
1684 // search downwards through overloaded methods
1685 int i;
1686 for (i = hit - 1; i >= 0; --i) {
1687 const Method* const m = methods->at(i);
1688 assert(m->is_method(), "must be method");
1689 if (m->name() != name) {
1690 break;
1691 }
1692 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1693 return i;
1694 }
1695 }
1696 // search upwards
1697 for (i = hit + 1; i < methods->length(); ++i) {
1698 const Method* const m = methods->at(i);
1699 assert(m->is_method(), "must be method");
1700 if (m->name() != name) {
1701 break;
1702 }
1703 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1704 return i;
1705 }
1706 }
1707 // not found
1708 #ifdef ASSERT
1709 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1710 linear_search(methods, name, signature);
1711 assert(-1 == index, "binary search should have found entry %d", index);
1712 #endif
1713 }
1714 return -1;
1715 }
1716
1717 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1718 return find_method_by_name(methods(), name, end);
1719 }
1720
1721 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1722 const Symbol* name,
1723 int* end_ptr) {
1724 assert(end_ptr != NULL, "just checking");
1725 int start = binary_search(methods, name);
1726 int end = start + 1;
1727 if (start != -1) {
1728 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1729 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1730 *end_ptr = end;
1731 return start;
1732 }
1733 return -1;
1734 }
1735
1736 // uncached_lookup_method searches both the local class methods array and all
1737 // superclasses methods arrays, skipping any overpass methods in superclasses.
1738 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1739 const Symbol* signature,
1740 OverpassLookupMode overpass_mode) const {
1741 OverpassLookupMode overpass_local_mode = overpass_mode;
1742 const Klass* klass = this;
1743 while (klass != NULL) {
1744 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1745 signature,
1746 overpass_local_mode,
1747 find_static,
1748 find_private);
1749 if (method != NULL) {
1750 return method;
1751 }
1752 klass = klass->super();
1753 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1754 }
1755 return NULL;
1756 }
1757
1758 #ifdef ASSERT
1759 // search through class hierarchy and return true if this class or
1760 // one of the superclasses was redefined
1761 bool InstanceKlass::has_redefined_this_or_super() const {
1762 const Klass* klass = this;
1763 while (klass != NULL) {
1764 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1765 return true;
1766 }
1767 klass = klass->super();
1768 }
1769 return false;
1770 }
1771 #endif
1772
1773 // lookup a method in the default methods list then in all transitive interfaces
1774 // Do NOT return private or static methods
1775 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1776 Symbol* signature) const {
1777 Method* m = NULL;
1778 if (default_methods() != NULL) {
1779 m = find_method(default_methods(), name, signature);
1780 }
1781 // Look up interfaces
1782 if (m == NULL) {
1783 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1784 }
1785 return m;
1786 }
1787
1788 // lookup a method in all the interfaces that this class implements
1789 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1790 // They should only be found in the initial InterfaceMethodRef
1791 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1792 Symbol* signature,
1793 DefaultsLookupMode defaults_mode) const {
1794 Array<Klass*>* all_ifs = transitive_interfaces();
1795 int num_ifs = all_ifs->length();
1796 InstanceKlass *ik = NULL;
1797 for (int i = 0; i < num_ifs; i++) {
1798 ik = InstanceKlass::cast(all_ifs->at(i));
1799 Method* m = ik->lookup_method(name, signature);
1800 if (m != NULL && m->is_public() && !m->is_static() &&
1801 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1802 return m;
1803 }
1804 }
1805 return NULL;
1806 }
1807
1808 /* jni_id_for_impl for jfieldIds only */
1809 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1810 MutexLocker ml(JfieldIdCreation_lock);
1811 // Retry lookup after we got the lock
1812 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1813 if (probe == NULL) {
1814 // Slow case, allocate new static field identifier
1815 probe = new JNIid(this, offset, jni_ids());
1816 set_jni_ids(probe);
1817 }
1818 return probe;
1819 }
1820
1821
1822 /* jni_id_for for jfieldIds only */
1823 JNIid* InstanceKlass::jni_id_for(int offset) {
1824 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1825 if (probe == NULL) {
1826 probe = jni_id_for_impl(offset);
1827 }
1828 return probe;
1829 }
1830
1831 u2 InstanceKlass::enclosing_method_data(int offset) const {
1832 const Array<jushort>* const inner_class_list = inner_classes();
1833 if (inner_class_list == NULL) {
1834 return 0;
1835 }
1836 const int length = inner_class_list->length();
1837 if (length % inner_class_next_offset == 0) {
1838 return 0;
1839 }
1840 const int index = length - enclosing_method_attribute_size;
1841 assert(offset < enclosing_method_attribute_size, "invalid offset");
1842 return inner_class_list->at(index + offset);
1843 }
1844
1845 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1846 u2 method_index) {
1847 Array<jushort>* inner_class_list = inner_classes();
1848 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1849 int length = inner_class_list->length();
1850 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1851 int index = length - enclosing_method_attribute_size;
1852 inner_class_list->at_put(
1853 index + enclosing_method_class_index_offset, class_index);
1854 inner_class_list->at_put(
1855 index + enclosing_method_method_index_offset, method_index);
1856 }
1857 }
1858
1859 // Lookup or create a jmethodID.
1860 // This code is called by the VMThread and JavaThreads so the
1861 // locking has to be done very carefully to avoid deadlocks
1862 // and/or other cache consistency problems.
1863 //
1864 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1865 size_t idnum = (size_t)method_h->method_idnum();
1866 jmethodID* jmeths = methods_jmethod_ids_acquire();
1867 size_t length = 0;
1868 jmethodID id = NULL;
1869
1870 // We use a double-check locking idiom here because this cache is
1871 // performance sensitive. In the normal system, this cache only
1872 // transitions from NULL to non-NULL which is safe because we use
1873 // release_set_methods_jmethod_ids() to advertise the new cache.
1874 // A partially constructed cache should never be seen by a racing
1875 // thread. We also use release_store_ptr() to save a new jmethodID
1876 // in the cache so a partially constructed jmethodID should never be
1877 // seen either. Cache reads of existing jmethodIDs proceed without a
1878 // lock, but cache writes of a new jmethodID requires uniqueness and
1879 // creation of the cache itself requires no leaks so a lock is
1880 // generally acquired in those two cases.
1881 //
1882 // If the RedefineClasses() API has been used, then this cache can
1883 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1884 // Cache creation requires no leaks and we require safety between all
1885 // cache accesses and freeing of the old cache so a lock is generally
1886 // acquired when the RedefineClasses() API has been used.
1887
1888 if (jmeths != NULL) {
1889 // the cache already exists
1890 if (!idnum_can_increment()) {
1891 // the cache can't grow so we can just get the current values
1892 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1893 } else {
1894 // cache can grow so we have to be more careful
1895 if (Threads::number_of_threads() == 0 ||
1896 SafepointSynchronize::is_at_safepoint()) {
1897 // we're single threaded or at a safepoint - no locking needed
1898 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1899 } else {
1900 MutexLocker ml(JmethodIdCreation_lock);
1901 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1902 }
1903 }
1904 }
1905 // implied else:
1906 // we need to allocate a cache so default length and id values are good
1907
1908 if (jmeths == NULL || // no cache yet
1909 length <= idnum || // cache is too short
1910 id == NULL) { // cache doesn't contain entry
1911
1912 // This function can be called by the VMThread so we have to do all
1913 // things that might block on a safepoint before grabbing the lock.
1914 // Otherwise, we can deadlock with the VMThread or have a cache
1915 // consistency issue. These vars keep track of what we might have
1916 // to free after the lock is dropped.
1917 jmethodID to_dealloc_id = NULL;
1918 jmethodID* to_dealloc_jmeths = NULL;
1919
1920 // may not allocate new_jmeths or use it if we allocate it
1921 jmethodID* new_jmeths = NULL;
1922 if (length <= idnum) {
1923 // allocate a new cache that might be used
1924 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1925 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1926 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1927 // cache size is stored in element[0], other elements offset by one
1928 new_jmeths[0] = (jmethodID)size;
1929 }
1930
1931 // allocate a new jmethodID that might be used
1932 jmethodID new_id = NULL;
1933 if (method_h->is_old() && !method_h->is_obsolete()) {
1934 // The method passed in is old (but not obsolete), we need to use the current version
1935 Method* current_method = method_with_idnum((int)idnum);
1936 assert(current_method != NULL, "old and but not obsolete, so should exist");
1937 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1938 } else {
1939 // It is the current version of the method or an obsolete method,
1940 // use the version passed in
1941 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1942 }
1943
1944 if (Threads::number_of_threads() == 0 ||
1945 SafepointSynchronize::is_at_safepoint()) {
1946 // we're single threaded or at a safepoint - no locking needed
1947 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1948 &to_dealloc_id, &to_dealloc_jmeths);
1949 } else {
1950 MutexLocker ml(JmethodIdCreation_lock);
1951 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1952 &to_dealloc_id, &to_dealloc_jmeths);
1953 }
1954
1955 // The lock has been dropped so we can free resources.
1956 // Free up either the old cache or the new cache if we allocated one.
1957 if (to_dealloc_jmeths != NULL) {
1958 FreeHeap(to_dealloc_jmeths);
1959 }
1960 // free up the new ID since it wasn't needed
1961 if (to_dealloc_id != NULL) {
1962 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1963 }
1964 }
1965 return id;
1966 }
1967
1968 // Figure out how many jmethodIDs haven't been allocated, and make
1969 // sure space for them is pre-allocated. This makes getting all
1970 // method ids much, much faster with classes with more than 8
1971 // methods, and has a *substantial* effect on performance with jvmti
1972 // code that loads all jmethodIDs for all classes.
1973 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1974 int new_jmeths = 0;
1975 int length = methods()->length();
1976 for (int index = start_offset; index < length; index++) {
1977 Method* m = methods()->at(index);
1978 jmethodID id = m->find_jmethod_id_or_null();
1979 if (id == NULL) {
1980 new_jmeths++;
1981 }
1982 }
1983 if (new_jmeths != 0) {
1984 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1985 }
1986 }
1987
1988 // Common code to fetch the jmethodID from the cache or update the
1989 // cache with the new jmethodID. This function should never do anything
1990 // that causes the caller to go to a safepoint or we can deadlock with
1991 // the VMThread or have cache consistency issues.
1992 //
1993 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1994 size_t idnum, jmethodID new_id,
1995 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1996 jmethodID** to_dealloc_jmeths_p) {
1997 assert(new_id != NULL, "sanity check");
1998 assert(to_dealloc_id_p != NULL, "sanity check");
1999 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2000 assert(Threads::number_of_threads() == 0 ||
2001 SafepointSynchronize::is_at_safepoint() ||
2002 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2003
2004 // reacquire the cache - we are locked, single threaded or at a safepoint
2005 jmethodID* jmeths = methods_jmethod_ids_acquire();
2006 jmethodID id = NULL;
2007 size_t length = 0;
2008
2009 if (jmeths == NULL || // no cache yet
2010 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2011 if (jmeths != NULL) {
2012 // copy any existing entries from the old cache
2013 for (size_t index = 0; index < length; index++) {
2014 new_jmeths[index+1] = jmeths[index+1];
2015 }
2016 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2017 }
2018 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2019 } else {
2020 // fetch jmethodID (if any) from the existing cache
2021 id = jmeths[idnum+1];
2022 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2023 }
2024 if (id == NULL) {
2025 // No matching jmethodID in the existing cache or we have a new
2026 // cache or we just grew the cache. This cache write is done here
2027 // by the first thread to win the foot race because a jmethodID
2028 // needs to be unique once it is generally available.
2029 id = new_id;
2030
2031 // The jmethodID cache can be read while unlocked so we have to
2032 // make sure the new jmethodID is complete before installing it
2033 // in the cache.
2034 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
2035 } else {
2036 *to_dealloc_id_p = new_id; // save new id for later delete
2037 }
2038 return id;
2039 }
2040
2041
2042 // Common code to get the jmethodID cache length and the jmethodID
2043 // value at index idnum if there is one.
2044 //
2045 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2046 size_t idnum, size_t *length_p, jmethodID* id_p) {
2047 assert(cache != NULL, "sanity check");
2048 assert(length_p != NULL, "sanity check");
2049 assert(id_p != NULL, "sanity check");
2050
2051 // cache size is stored in element[0], other elements offset by one
2052 *length_p = (size_t)cache[0];
2053 if (*length_p <= idnum) { // cache is too short
2054 *id_p = NULL;
2055 } else {
2056 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2057 }
2058 }
2059
2060
2061 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2062 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2063 size_t idnum = (size_t)method->method_idnum();
2064 jmethodID* jmeths = methods_jmethod_ids_acquire();
2065 size_t length; // length assigned as debugging crumb
2066 jmethodID id = NULL;
2067 if (jmeths != NULL && // If there is a cache
2068 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2069 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2070 }
2071 return id;
2072 }
2073
2074 inline DependencyContext InstanceKlass::dependencies() {
2075 DependencyContext dep_context(&_dep_context);
2076 return dep_context;
2077 }
2078
2079 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2080 return dependencies().mark_dependent_nmethods(changes);
2081 }
2082
2083 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2084 dependencies().add_dependent_nmethod(nm);
2085 }
2086
2087 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2088 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2089 }
2090
2091 #ifndef PRODUCT
2092 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2093 dependencies().print_dependent_nmethods(verbose);
2094 }
2095
2096 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2097 return dependencies().is_dependent_nmethod(nm);
2098 }
2099 #endif //PRODUCT
2100
2101 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2102 clean_implementors_list(is_alive);
2103 clean_method_data(is_alive);
2104
2105 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2106 DependencyContext dep_context(&_dep_context);
2107 dep_context.expunge_stale_entries();
2108 }
2109
2110 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2111 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2112 if (is_interface()) {
2113 if (ClassUnloading) {
2114 Klass* impl = implementor();
2115 if (impl != NULL) {
2116 if (!impl->is_loader_alive(is_alive)) {
2117 // remove this guy
2118 Klass** klass = adr_implementor();
2119 assert(klass != NULL, "null klass");
2120 if (klass != NULL) {
2121 *klass = NULL;
2122 }
2123 }
2124 }
2125 }
2126 }
2127 }
2128
2129 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2130 for (int m = 0; m < methods()->length(); m++) {
2131 MethodData* mdo = methods()->at(m)->method_data();
2132 if (mdo != NULL) {
2133 mdo->clean_method_data(is_alive);
2134 }
2135 }
2136 }
2137
2138 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2139 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2140 ResourceMark rm;
2141 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2142 return false;
2143 }
2144
2145 Array<Klass*>* local_interfaces = this->local_interfaces();
2146 if (local_interfaces != NULL) {
2147 int length = local_interfaces->length();
2148 for (int i = 0; i < length; i++) {
2149 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2150 if (!intf->has_passed_fingerprint_check()) {
2151 ResourceMark rm;
2152 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2153 return false;
2154 }
2155 }
2156 }
2157
2158 return true;
2159 }
2160
2161 bool InstanceKlass::should_store_fingerprint() {
2162 #if INCLUDE_AOT
2163 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2164 if (CalculateClassFingerprint) {
2165 // (1) We are running AOT to generate a shared library.
2166 return true;
2167 }
2168 if (DumpSharedSpaces) {
2169 // (2) We are running -Xshare:dump to create a shared archive
2170 return true;
2171 }
2172 #endif
2173
2174 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2175 // but do not store the 64-bit fingerprint to save space.
2176 return false;
2177 }
2178
2179 bool InstanceKlass::has_stored_fingerprint() const {
2180 #if INCLUDE_AOT
2181 return should_store_fingerprint() || is_shared();
2182 #else
2183 return false;
2184 #endif
2185 }
2186
2187 uint64_t InstanceKlass::get_stored_fingerprint() const {
2188 address adr = adr_fingerprint();
2189 if (adr != NULL) {
2190 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2191 }
2192 return 0;
2193 }
2194
2195 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2196 address adr = adr_fingerprint();
2197 if (adr != NULL) {
2198 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2199
2200 ResourceMark rm;
2201 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2202 }
2203 }
2204
2205 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2206 Klass::metaspace_pointers_do(it);
2207
2208 if (log_is_enabled(Trace, cds)) {
2209 ResourceMark rm;
2210 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2211 }
2212
2213 it->push(&_annotations);
2214 it->push((Klass**)&_array_klasses);
2215 it->push(&_constants);
2216 it->push(&_inner_classes);
2217 it->push(&_array_name);
2218 #if INCLUDE_JVMTI
2219 it->push(&_previous_versions);
2220 #endif
2221 it->push(&_methods);
2222 it->push(&_default_methods);
2223 it->push(&_local_interfaces);
2224 it->push(&_transitive_interfaces);
2225 it->push(&_method_ordering);
2226 it->push(&_default_vtable_indices);
2227 it->push(&_fields);
2228
2229 if (itable_length() > 0) {
2230 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2231 int method_table_offset_in_words = ioe->offset()/wordSize;
2232 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2233 / itableOffsetEntry::size();
2234
2235 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2236 if (ioe->interface_klass() != NULL) {
2237 it->push(ioe->interface_klass_addr());
2238 itableMethodEntry* ime = ioe->first_method_entry(this);
2239 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2240 for (int index = 0; index < n; index ++) {
2241 it->push(ime[index].method_addr());
2242 }
2243 }
2244 }
2245 }
2246
2247 it->push(&_nest_members);
2248 }
2249
2250 void InstanceKlass::remove_unshareable_info() {
2251 Klass::remove_unshareable_info();
2252
2253 if (is_in_error_state()) {
2254 // Classes are attempted to link during dumping and may fail,
2255 // but these classes are still in the dictionary and class list in CLD.
2256 // Check in_error state first because in_error is > linked state, so
2257 // is_linked() is true.
2258 // If there's a linking error, there is nothing else to remove.
2259 return;
2260 }
2261
2262 // Unlink the class
2263 if (is_linked()) {
2264 unlink_class();
2265 }
2266 init_implementor();
2267
2268 constants()->remove_unshareable_info();
2269
2270 for (int i = 0; i < methods()->length(); i++) {
2271 Method* m = methods()->at(i);
2272 m->remove_unshareable_info();
2273 }
2274
2275 // do array classes also.
2276 if (array_klasses() != NULL) {
2277 array_klasses()->remove_unshareable_info();
2278 }
2279
2280 // These are not allocated from metaspace, but they should should all be empty
2281 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2282 guarantee(_source_debug_extension == NULL, "must be");
2283 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2284 guarantee(_osr_nmethods_head == NULL, "must be");
2285
2286 #if INCLUDE_JVMTI
2287 guarantee(_breakpoints == NULL, "must be");
2288 guarantee(_previous_versions == NULL, "must be");
2289 #endif
2290
2291 _init_thread = NULL;
2292 _methods_jmethod_ids = NULL;
2293 _jni_ids = NULL;
2294 _oop_map_cache = NULL;
2295 // clear _nest_host to ensure re-load at runtime
2296 _nest_host = NULL;
2297 }
2298
2299 void InstanceKlass::remove_java_mirror() {
2300 Klass::remove_java_mirror();
2301
2302 // do array classes also.
2303 if (array_klasses() != NULL) {
2304 array_klasses()->remove_java_mirror();
2305 }
2306 }
2307
2308 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2309 set_package(loader_data, CHECK);
2310 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2311
2312 Array<Method*>* methods = this->methods();
2313 int num_methods = methods->length();
2314 for (int index2 = 0; index2 < num_methods; ++index2) {
2315 methodHandle m(THREAD, methods->at(index2));
2316 m->restore_unshareable_info(CHECK);
2317 }
2318 if (JvmtiExport::has_redefined_a_class()) {
2319 // Reinitialize vtable because RedefineClasses may have changed some
2320 // entries in this vtable for super classes so the CDS vtable might
2321 // point to old or obsolete entries. RedefineClasses doesn't fix up
2322 // vtables in the shared system dictionary, only the main one.
2323 // It also redefines the itable too so fix that too.
2324 ResourceMark rm(THREAD);
2325 vtable().initialize_vtable(false, CHECK);
2326 itable().initialize_itable(false, CHECK);
2327 }
2328
2329 // restore constant pool resolved references
2330 constants()->restore_unshareable_info(CHECK);
2331
2332 if (array_klasses() != NULL) {
2333 // Array classes have null protection domain.
2334 // --> see ArrayKlass::complete_create_array_klass()
2335 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2336 }
2337 }
2338
2339 // returns true IFF is_in_error_state() has been changed as a result of this call.
2340 bool InstanceKlass::check_sharing_error_state() {
2341 assert(DumpSharedSpaces, "should only be called during dumping");
2342 bool old_state = is_in_error_state();
2343
2344 if (!is_in_error_state()) {
2345 bool bad = false;
2346 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2347 if (sup->is_in_error_state()) {
2348 bad = true;
2349 break;
2350 }
2351 }
2352 if (!bad) {
2353 Array<Klass*>* interfaces = transitive_interfaces();
2354 for (int i = 0; i < interfaces->length(); i++) {
2355 Klass* iface = interfaces->at(i);
2356 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2357 bad = true;
2358 break;
2359 }
2360 }
2361 }
2362
2363 if (bad) {
2364 set_in_error_state();
2365 }
2366 }
2367
2368 return (old_state != is_in_error_state());
2369 }
2370
2371 #if INCLUDE_JVMTI
2372 static void clear_all_breakpoints(Method* m) {
2373 m->clear_all_breakpoints();
2374 }
2375 #endif
2376
2377 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2378 // notify the debugger
2379 if (JvmtiExport::should_post_class_unload()) {
2380 JvmtiExport::post_class_unload(ik);
2381 }
2382
2383 // notify ClassLoadingService of class unload
2384 ClassLoadingService::notify_class_unloaded(ik);
2385 }
2386
2387 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2388 // Clean up C heap
2389 ik->release_C_heap_structures();
2390 ik->constants()->release_C_heap_structures();
2391 }
2392
2393 void InstanceKlass::release_C_heap_structures() {
2394 // Can't release the constant pool here because the constant pool can be
2395 // deallocated separately from the InstanceKlass for default methods and
2396 // redefine classes.
2397
2398 // Deallocate oop map cache
2399 if (_oop_map_cache != NULL) {
2400 delete _oop_map_cache;
2401 _oop_map_cache = NULL;
2402 }
2403
2404 // Deallocate JNI identifiers for jfieldIDs
2405 JNIid::deallocate(jni_ids());
2406 set_jni_ids(NULL);
2407
2408 jmethodID* jmeths = methods_jmethod_ids_acquire();
2409 if (jmeths != (jmethodID*)NULL) {
2410 release_set_methods_jmethod_ids(NULL);
2411 FreeHeap(jmeths);
2412 }
2413
2414 // Release dependencies.
2415 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2416 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2417 // context can contain live dependencies, since there's a race between nmethod &
2418 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2419 // dependencies aren't removed from the context associated with the class (see
2420 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2421 // live dependencies pointing to unloaded nmethods and causes a crash in
2422 // DC::remove_all_dependents() when it touches unloaded nmethod.
2423 dependencies().wipe();
2424
2425 #if INCLUDE_JVMTI
2426 // Deallocate breakpoint records
2427 if (breakpoints() != 0x0) {
2428 methods_do(clear_all_breakpoints);
2429 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2430 }
2431
2432 // deallocate the cached class file
2433 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) {
2434 os::free(_cached_class_file);
2435 _cached_class_file = NULL;
2436 }
2437 #endif
2438
2439 // Decrement symbol reference counts associated with the unloaded class.
2440 if (_name != NULL) _name->decrement_refcount();
2441 // unreference array name derived from this class name (arrays of an unloaded
2442 // class can't be referenced anymore).
2443 if (_array_name != NULL) _array_name->decrement_refcount();
2444 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2445
2446 assert(_total_instanceKlass_count >= 1, "Sanity check");
2447 Atomic::dec(&_total_instanceKlass_count);
2448 }
2449
2450 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2451 if (array == NULL) {
2452 _source_debug_extension = NULL;
2453 } else {
2454 // Adding one to the attribute length in order to store a null terminator
2455 // character could cause an overflow because the attribute length is
2456 // already coded with an u4 in the classfile, but in practice, it's
2457 // unlikely to happen.
2458 assert((length+1) > length, "Overflow checking");
2459 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2460 for (int i = 0; i < length; i++) {
2461 sde[i] = array[i];
2462 }
2463 sde[length] = '\0';
2464 _source_debug_extension = sde;
2465 }
2466 }
2467
2468 address InstanceKlass::static_field_addr(int offset) {
2469 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2470 }
2471
2472
2473 const char* InstanceKlass::signature_name() const {
2474 int hash_len = 0;
2475 char hash_buf[40];
2476
2477 // If this is an anonymous class, append a hash to make the name unique
2478 if (is_anonymous()) {
2479 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2480 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2481 hash_len = (int)strlen(hash_buf);
2482 }
2483
2484 // Get the internal name as a c string
2485 const char* src = (const char*) (name()->as_C_string());
2486 const int src_length = (int)strlen(src);
2487
2488 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2489
2490 // Add L as type indicator
2491 int dest_index = 0;
2492 dest[dest_index++] = 'L';
2493
2494 // Add the actual class name
2495 for (int src_index = 0; src_index < src_length; ) {
2496 dest[dest_index++] = src[src_index++];
2497 }
2498
2499 // If we have a hash, append it
2500 for (int hash_index = 0; hash_index < hash_len; ) {
2501 dest[dest_index++] = hash_buf[hash_index++];
2502 }
2503
2504 // Add the semicolon and the NULL
2505 dest[dest_index++] = ';';
2506 dest[dest_index] = '\0';
2507 return dest;
2508 }
2509
2510 // Used to obtain the package name from a fully qualified class name.
2511 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2512 if (name == NULL) {
2513 return NULL;
2514 } else {
2515 if (name->utf8_length() <= 0) {
2516 return NULL;
2517 }
2518 ResourceMark rm;
2519 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2520 if (package_name == NULL) {
2521 return NULL;
2522 }
2523 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2524 return pkg_name;
2525 }
2526 }
2527
2528 ModuleEntry* InstanceKlass::module() const {
2529 if (!in_unnamed_package()) {
2530 return _package_entry->module();
2531 }
2532 const Klass* host = host_klass();
2533 if (host == NULL) {
2534 return class_loader_data()->unnamed_module();
2535 }
2536 return host->class_loader_data()->unnamed_module();
2537 }
2538
2539 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2540
2541 // ensure java/ packages only loaded by boot or platform builtin loaders
2542 Handle class_loader(THREAD, loader_data->class_loader());
2543 check_prohibited_package(name(), class_loader, CHECK);
2544
2545 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2546
2547 if (pkg_name != NULL && loader_data != NULL) {
2548
2549 // Find in class loader's package entry table.
2550 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2551
2552 // If the package name is not found in the loader's package
2553 // entry table, it is an indication that the package has not
2554 // been defined. Consider it defined within the unnamed module.
2555 if (_package_entry == NULL) {
2556 ResourceMark rm;
2557
2558 if (!ModuleEntryTable::javabase_defined()) {
2559 // Before java.base is defined during bootstrapping, define all packages in
2560 // the java.base module. If a non-java.base package is erroneously placed
2561 // in the java.base module it will be caught later when java.base
2562 // is defined by ModuleEntryTable::verify_javabase_packages check.
2563 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2564 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2565 } else {
2566 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2567 _package_entry = loader_data->packages()->lookup(pkg_name,
2568 loader_data->unnamed_module());
2569 }
2570
2571 // A package should have been successfully created
2572 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2573 name()->as_C_string(), loader_data->loader_name());
2574 }
2575
2576 if (log_is_enabled(Debug, module)) {
2577 ResourceMark rm;
2578 ModuleEntry* m = _package_entry->module();
2579 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2580 external_name(),
2581 pkg_name->as_C_string(),
2582 loader_data->loader_name(),
2583 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2584 }
2585 } else {
2586 ResourceMark rm;
2587 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2588 external_name(),
2589 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2590 UNNAMED_MODULE);
2591 }
2592 }
2593
2594
2595 // different versions of is_same_class_package
2596
2597 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2598 oop classloader1 = this->class_loader();
2599 PackageEntry* classpkg1 = this->package();
2600 if (class2->is_objArray_klass()) {
2601 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2602 }
2603
2604 oop classloader2;
2605 PackageEntry* classpkg2;
2606 if (class2->is_instance_klass()) {
2607 classloader2 = class2->class_loader();
2608 classpkg2 = class2->package();
2609 } else {
2610 assert(class2->is_typeArray_klass(), "should be type array");
2611 classloader2 = NULL;
2612 classpkg2 = NULL;
2613 }
2614
2615 // Same package is determined by comparing class loader
2616 // and package entries. Both must be the same. This rule
2617 // applies even to classes that are defined in the unnamed
2618 // package, they still must have the same class loader.
2619 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2620 return true;
2621 }
2622
2623 return false;
2624 }
2625
2626 // return true if this class and other_class are in the same package. Classloader
2627 // and classname information is enough to determine a class's package
2628 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2629 const Symbol* other_class_name) const {
2630 if (class_loader() != other_class_loader) {
2631 return false;
2632 }
2633 if (name()->fast_compare(other_class_name) == 0) {
2634 return true;
2635 }
2636
2637 {
2638 ResourceMark rm;
2639
2640 bool bad_class_name = false;
2641 const char* other_pkg =
2642 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2643 if (bad_class_name) {
2644 return false;
2645 }
2646 // Check that package_from_name() returns NULL, not "", if there is no package.
2647 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2648
2649 const Symbol* const this_package_name =
2650 this->package() != NULL ? this->package()->name() : NULL;
2651
2652 if (this_package_name == NULL || other_pkg == NULL) {
2653 // One of the two doesn't have a package. Only return true if the other
2654 // one also doesn't have a package.
2655 return (const char*)this_package_name == other_pkg;
2656 }
2657
2658 // Check if package is identical
2659 return this_package_name->equals(other_pkg);
2660 }
2661 }
2662
2663 // Returns true iff super_method can be overridden by a method in targetclassname
2664 // See JLS 3rd edition 8.4.6.1
2665 // Assumes name-signature match
2666 // "this" is InstanceKlass of super_method which must exist
2667 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2668 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2669 // Private methods can not be overridden
2670 if (super_method->is_private()) {
2671 return false;
2672 }
2673 // If super method is accessible, then override
2674 if ((super_method->is_protected()) ||
2675 (super_method->is_public())) {
2676 return true;
2677 }
2678 // Package-private methods are not inherited outside of package
2679 assert(super_method->is_package_private(), "must be package private");
2680 return(is_same_class_package(targetclassloader(), targetclassname));
2681 }
2682
2683 // Only boot and platform class loaders can define classes in "java/" packages.
2684 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2685 Handle class_loader,
2686 TRAPS) {
2687 if (!class_loader.is_null() &&
2688 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2689 class_name != NULL) {
2690 ResourceMark rm(THREAD);
2691 char* name = class_name->as_C_string();
2692 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2693 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2694 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2695 name = pkg_name->as_C_string();
2696 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2697 StringUtils::replace_no_expand(name, "/", ".");
2698 const char* msg_text1 = "Class loader (instance of): ";
2699 const char* msg_text2 = " tried to load prohibited package name: ";
2700 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2701 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2702 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2703 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2704 }
2705 }
2706 return;
2707 }
2708
2709 // tell if two classes have the same enclosing class (at package level)
2710 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2711 if (class2 == this) return true;
2712 if (!class2->is_instance_klass()) return false;
2713
2714 // must be in same package before we try anything else
2715 if (!is_same_class_package(class2))
2716 return false;
2717
2718 // As long as there is an outer_this.getEnclosingClass,
2719 // shift the search outward.
2720 const InstanceKlass* outer_this = this;
2721 for (;;) {
2722 // As we walk along, look for equalities between outer_this and class2.
2723 // Eventually, the walks will terminate as outer_this stops
2724 // at the top-level class around the original class.
2725 bool ignore_inner_is_member;
2726 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2727 CHECK_false);
2728 if (next == NULL) break;
2729 if (next == class2) return true;
2730 outer_this = InstanceKlass::cast(next);
2731 }
2732
2733 // Now do the same for class2.
2734 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2735 for (;;) {
2736 bool ignore_inner_is_member;
2737 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2738 CHECK_false);
2739 if (next == NULL) break;
2740 // Might as well check the new outer against all available values.
2741 if (next == this) return true;
2742 if (next == outer_this) return true;
2743 outer2 = InstanceKlass::cast(next);
2744 }
2745
2746 // If by this point we have not found an equality between the
2747 // two classes, we know they are in separate package members.
2748 return false;
2749 }
2750
2751 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2752 constantPoolHandle i_cp(THREAD, constants());
2753 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2754 int ioff = iter.inner_class_info_index();
2755 if (ioff != 0) {
2756 // Check to see if the name matches the class we're looking for
2757 // before attempting to find the class.
2758 if (i_cp->klass_name_at_matches(this, ioff)) {
2759 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2760 if (this == inner_klass) {
2761 *ooff = iter.outer_class_info_index();
2762 *noff = iter.inner_name_index();
2763 return true;
2764 }
2765 }
2766 }
2767 }
2768 return false;
2769 }
2770
2771 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2772 InstanceKlass* outer_klass = NULL;
2773 *inner_is_member = false;
2774 int ooff = 0, noff = 0;
2775 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2776 if (has_inner_classes_attr) {
2777 constantPoolHandle i_cp(THREAD, constants());
2778 if (ooff != 0) {
2779 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2780 outer_klass = InstanceKlass::cast(ok);
2781 *inner_is_member = true;
2782 }
2783 if (NULL == outer_klass) {
2784 // It may be anonymous; try for that.
2785 int encl_method_class_idx = enclosing_method_class_index();
2786 if (encl_method_class_idx != 0) {
2787 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2788 outer_klass = InstanceKlass::cast(ok);
2789 *inner_is_member = false;
2790 }
2791 }
2792 }
2793
2794 // If no inner class attribute found for this class.
2795 if (NULL == outer_klass) return NULL;
2796
2797 // Throws an exception if outer klass has not declared k as an inner klass
2798 // We need evidence that each klass knows about the other, or else
2799 // the system could allow a spoof of an inner class to gain access rights.
2800 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2801 return outer_klass;
2802 }
2803
2804 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2805 jint access = access_flags().as_int();
2806
2807 // But check if it happens to be member class.
2808 InnerClassesIterator iter(this);
2809 for (; !iter.done(); iter.next()) {
2810 int ioff = iter.inner_class_info_index();
2811 // Inner class attribute can be zero, skip it.
2812 // Strange but true: JVM spec. allows null inner class refs.
2813 if (ioff == 0) continue;
2814
2815 // only look at classes that are already loaded
2816 // since we are looking for the flags for our self.
2817 Symbol* inner_name = constants()->klass_name_at(ioff);
2818 if (name() == inner_name) {
2819 // This is really a member class.
2820 access = iter.inner_access_flags();
2821 break;
2822 }
2823 }
2824 // Remember to strip ACC_SUPER bit
2825 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2826 }
2827
2828 jint InstanceKlass::jvmti_class_status() const {
2829 jint result = 0;
2830
2831 if (is_linked()) {
2832 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2833 }
2834
2835 if (is_initialized()) {
2836 assert(is_linked(), "Class status is not consistent");
2837 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2838 }
2839 if (is_in_error_state()) {
2840 result |= JVMTI_CLASS_STATUS_ERROR;
2841 }
2842 return result;
2843 }
2844
2845 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2846 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2847 int method_table_offset_in_words = ioe->offset()/wordSize;
2848 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2849 / itableOffsetEntry::size();
2850
2851 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2852 // If the interface isn't implemented by the receiver class,
2853 // the VM should throw IncompatibleClassChangeError.
2854 if (cnt >= nof_interfaces) {
2855 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2856 }
2857
2858 Klass* ik = ioe->interface_klass();
2859 if (ik == holder) break;
2860 }
2861
2862 itableMethodEntry* ime = ioe->first_method_entry(this);
2863 Method* m = ime[index].method();
2864 if (m == NULL) {
2865 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2866 }
2867 return m;
2868 }
2869
2870
2871 #if INCLUDE_JVMTI
2872 // update default_methods for redefineclasses for methods that are
2873 // not yet in the vtable due to concurrent subclass define and superinterface
2874 // redefinition
2875 // Note: those in the vtable, should have been updated via adjust_method_entries
2876 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2877 // search the default_methods for uses of either obsolete or EMCP methods
2878 if (default_methods() != NULL) {
2879 for (int index = 0; index < default_methods()->length(); index ++) {
2880 Method* old_method = default_methods()->at(index);
2881 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2882 continue; // skip uninteresting entries
2883 }
2884 assert(!old_method->is_deleted(), "default methods may not be deleted");
2885
2886 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2887
2888 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2889 assert(old_method != new_method, "sanity check");
2890
2891 default_methods()->at_put(index, new_method);
2892 if (log_is_enabled(Info, redefine, class, update)) {
2893 ResourceMark rm;
2894 if (!(*trace_name_printed)) {
2895 log_info(redefine, class, update)
2896 ("adjust: klassname=%s default methods from name=%s",
2897 external_name(), old_method->method_holder()->external_name());
2898 *trace_name_printed = true;
2899 }
2900 log_debug(redefine, class, update, vtables)
2901 ("default method update: %s(%s) ",
2902 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2903 }
2904 }
2905 }
2906 }
2907 #endif // INCLUDE_JVMTI
2908
2909 // On-stack replacement stuff
2910 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2911 // only one compilation can be active
2912 {
2913 // This is a short non-blocking critical region, so the no safepoint check is ok.
2914 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2915 assert(n->is_osr_method(), "wrong kind of nmethod");
2916 n->set_osr_link(osr_nmethods_head());
2917 set_osr_nmethods_head(n);
2918 // Raise the highest osr level if necessary
2919 if (TieredCompilation) {
2920 Method* m = n->method();
2921 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2922 }
2923 }
2924
2925 // Get rid of the osr methods for the same bci that have lower levels.
2926 if (TieredCompilation) {
2927 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2928 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2929 if (inv != NULL && inv->is_in_use()) {
2930 inv->make_not_entrant();
2931 }
2932 }
2933 }
2934 }
2935
2936 // Remove osr nmethod from the list. Return true if found and removed.
2937 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2938 // This is a short non-blocking critical region, so the no safepoint check is ok.
2939 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2940 assert(n->is_osr_method(), "wrong kind of nmethod");
2941 nmethod* last = NULL;
2942 nmethod* cur = osr_nmethods_head();
2943 int max_level = CompLevel_none; // Find the max comp level excluding n
2944 Method* m = n->method();
2945 // Search for match
2946 bool found = false;
2947 while(cur != NULL && cur != n) {
2948 if (TieredCompilation && m == cur->method()) {
2949 // Find max level before n
2950 max_level = MAX2(max_level, cur->comp_level());
2951 }
2952 last = cur;
2953 cur = cur->osr_link();
2954 }
2955 nmethod* next = NULL;
2956 if (cur == n) {
2957 found = true;
2958 next = cur->osr_link();
2959 if (last == NULL) {
2960 // Remove first element
2961 set_osr_nmethods_head(next);
2962 } else {
2963 last->set_osr_link(next);
2964 }
2965 }
2966 n->set_osr_link(NULL);
2967 if (TieredCompilation) {
2968 cur = next;
2969 while (cur != NULL) {
2970 // Find max level after n
2971 if (m == cur->method()) {
2972 max_level = MAX2(max_level, cur->comp_level());
2973 }
2974 cur = cur->osr_link();
2975 }
2976 m->set_highest_osr_comp_level(max_level);
2977 }
2978 return found;
2979 }
2980
2981 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2982 // This is a short non-blocking critical region, so the no safepoint check is ok.
2983 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2984 nmethod* osr = osr_nmethods_head();
2985 int found = 0;
2986 while (osr != NULL) {
2987 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2988 if (osr->method() == m) {
2989 osr->mark_for_deoptimization();
2990 found++;
2991 }
2992 osr = osr->osr_link();
2993 }
2994 return found;
2995 }
2996
2997 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2998 // This is a short non-blocking critical region, so the no safepoint check is ok.
2999 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3000 nmethod* osr = osr_nmethods_head();
3001 nmethod* best = NULL;
3002 while (osr != NULL) {
3003 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3004 // There can be a time when a c1 osr method exists but we are waiting
3005 // for a c2 version. When c2 completes its osr nmethod we will trash
3006 // the c1 version and only be able to find the c2 version. However
3007 // while we overflow in the c1 code at back branches we don't want to
3008 // try and switch to the same code as we are already running
3009
3010 if (osr->method() == m &&
3011 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3012 if (match_level) {
3013 if (osr->comp_level() == comp_level) {
3014 // Found a match - return it.
3015 return osr;
3016 }
3017 } else {
3018 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3019 if (osr->comp_level() == CompLevel_highest_tier) {
3020 // Found the best possible - return it.
3021 return osr;
3022 }
3023 best = osr;
3024 }
3025 }
3026 }
3027 osr = osr->osr_link();
3028 }
3029 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3030 return best;
3031 }
3032 return NULL;
3033 }
3034
3035 // -----------------------------------------------------------------------------------------------------
3036 // Printing
3037
3038 #ifndef PRODUCT
3039
3040 #define BULLET " - "
3041
3042 static const char* state_names[] = {
3043 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3044 };
3045
3046 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3047 for (int i = 0; i < len; i++) {
3048 intptr_t e = start[i];
3049 st->print("%d : " INTPTR_FORMAT, i, e);
3050 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3051 st->print(" ");
3052 ((Metadata*)e)->print_value_on(st);
3053 }
3054 st->cr();
3055 }
3056 }
3057
3058 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3059 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3060 }
3061
3062 void InstanceKlass::print_on(outputStream* st) const {
3063 assert(is_klass(), "must be klass");
3064 Klass::print_on(st);
3065
3066 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3067 st->print(BULLET"klass size: %d", size()); st->cr();
3068 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3069 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3070 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3071 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3072 st->print(BULLET"sub: ");
3073 Klass* sub = subklass();
3074 int n;
3075 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3076 if (n < MaxSubklassPrintSize) {
3077 sub->print_value_on(st);
3078 st->print(" ");
3079 }
3080 }
3081 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3082 st->cr();
3083
3084 if (is_interface()) {
3085 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3086 if (nof_implementors() == 1) {
3087 st->print_cr(BULLET"implementor: ");
3088 st->print(" ");
3089 implementor()->print_value_on(st);
3090 st->cr();
3091 }
3092 }
3093
3094 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3095 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3096 if (Verbose || WizardMode) {
3097 Array<Method*>* method_array = methods();
3098 for (int i = 0; i < method_array->length(); i++) {
3099 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3100 }
3101 }
3102 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3103 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3104 if (Verbose && default_methods() != NULL) {
3105 Array<Method*>* method_array = default_methods();
3106 for (int i = 0; i < method_array->length(); i++) {
3107 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3108 }
3109 }
3110 if (default_vtable_indices() != NULL) {
3111 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3112 }
3113 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3114 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3115 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3116 if (class_loader_data() != NULL) {
3117 st->print(BULLET"class loader data: ");
3118 class_loader_data()->print_value_on(st);
3119 st->cr();
3120 }
3121 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3122 if (source_file_name() != NULL) {
3123 st->print(BULLET"source file: ");
3124 source_file_name()->print_value_on(st);
3125 st->cr();
3126 }
3127 if (source_debug_extension() != NULL) {
3128 st->print(BULLET"source debug extension: ");
3129 st->print("%s", source_debug_extension());
3130 st->cr();
3131 }
3132 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3133 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3134 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3135 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3136 {
3137 bool have_pv = false;
3138 // previous versions are linked together through the InstanceKlass
3139 for (InstanceKlass* pv_node = previous_versions();
3140 pv_node != NULL;
3141 pv_node = pv_node->previous_versions()) {
3142 if (!have_pv)
3143 st->print(BULLET"previous version: ");
3144 have_pv = true;
3145 pv_node->constants()->print_value_on(st);
3146 }
3147 if (have_pv) st->cr();
3148 }
3149
3150 if (generic_signature() != NULL) {
3151 st->print(BULLET"generic signature: ");
3152 generic_signature()->print_value_on(st);
3153 st->cr();
3154 }
3155 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3156 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3157 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3158 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3159 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3160 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3161 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3162 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3163 FieldPrinter print_static_field(st);
3164 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3165 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3166 FieldPrinter print_nonstatic_field(st);
3167 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3168 ik->do_nonstatic_fields(&print_nonstatic_field);
3169
3170 st->print(BULLET"non-static oop maps: ");
3171 OopMapBlock* map = start_of_nonstatic_oop_maps();
3172 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3173 while (map < end_map) {
3174 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3175 map++;
3176 }
3177 st->cr();
3178 }
3179
3180 #endif //PRODUCT
3181
3182 void InstanceKlass::print_value_on(outputStream* st) const {
3183 assert(is_klass(), "must be klass");
3184 if (Verbose || WizardMode) access_flags().print_on(st);
3185 name()->print_value_on(st);
3186 }
3187
3188 #ifndef PRODUCT
3189
3190 void FieldPrinter::do_field(fieldDescriptor* fd) {
3191 _st->print(BULLET);
3192 if (_obj == NULL) {
3193 fd->print_on(_st);
3194 _st->cr();
3195 } else {
3196 fd->print_on_for(_st, _obj);
3197 _st->cr();
3198 }
3199 }
3200
3201
3202 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3203 Klass::oop_print_on(obj, st);
3204
3205 if (this == SystemDictionary::String_klass()) {
3206 typeArrayOop value = java_lang_String::value(obj);
3207 juint length = java_lang_String::length(obj);
3208 if (value != NULL &&
3209 value->is_typeArray() &&
3210 length <= (juint) value->length()) {
3211 st->print(BULLET"string: ");
3212 java_lang_String::print(obj, st);
3213 st->cr();
3214 if (!WizardMode) return; // that is enough
3215 }
3216 }
3217
3218 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3219 FieldPrinter print_field(st, obj);
3220 do_nonstatic_fields(&print_field);
3221
3222 if (this == SystemDictionary::Class_klass()) {
3223 st->print(BULLET"signature: ");
3224 java_lang_Class::print_signature(obj, st);
3225 st->cr();
3226 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3227 st->print(BULLET"fake entry for mirror: ");
3228 mirrored_klass->print_value_on_maybe_null(st);
3229 st->cr();
3230 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3231 st->print(BULLET"fake entry for array: ");
3232 array_klass->print_value_on_maybe_null(st);
3233 st->cr();
3234 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3235 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3236 Klass* real_klass = java_lang_Class::as_Klass(obj);
3237 if (real_klass != NULL && real_klass->is_instance_klass()) {
3238 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3239 }
3240 } else if (this == SystemDictionary::MethodType_klass()) {
3241 st->print(BULLET"signature: ");
3242 java_lang_invoke_MethodType::print_signature(obj, st);
3243 st->cr();
3244 }
3245 }
3246
3247 #endif //PRODUCT
3248
3249 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3250 st->print("a ");
3251 name()->print_value_on(st);
3252 obj->print_address_on(st);
3253 if (this == SystemDictionary::String_klass()
3254 && java_lang_String::value(obj) != NULL) {
3255 ResourceMark rm;
3256 int len = java_lang_String::length(obj);
3257 int plen = (len < 24 ? len : 12);
3258 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3259 st->print(" = \"%s\"", str);
3260 if (len > plen)
3261 st->print("...[%d]", len);
3262 } else if (this == SystemDictionary::Class_klass()) {
3263 Klass* k = java_lang_Class::as_Klass(obj);
3264 st->print(" = ");
3265 if (k != NULL) {
3266 k->print_value_on(st);
3267 } else {
3268 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3269 st->print("%s", tname ? tname : "type?");
3270 }
3271 } else if (this == SystemDictionary::MethodType_klass()) {
3272 st->print(" = ");
3273 java_lang_invoke_MethodType::print_signature(obj, st);
3274 } else if (java_lang_boxing_object::is_instance(obj)) {
3275 st->print(" = ");
3276 java_lang_boxing_object::print(obj, st);
3277 } else if (this == SystemDictionary::LambdaForm_klass()) {
3278 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3279 if (vmentry != NULL) {
3280 st->print(" => ");
3281 vmentry->print_value_on(st);
3282 }
3283 } else if (this == SystemDictionary::MemberName_klass()) {
3284 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3285 if (vmtarget != NULL) {
3286 st->print(" = ");
3287 vmtarget->print_value_on(st);
3288 } else {
3289 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3290 st->print(".");
3291 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3292 }
3293 }
3294 }
3295
3296 const char* InstanceKlass::internal_name() const {
3297 return external_name();
3298 }
3299
3300 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3301 const char* module_name,
3302 const ClassFileStream* cfs) const {
3303 if (!log_is_enabled(Info, class, load)) {
3304 return;
3305 }
3306
3307 ResourceMark rm;
3308 LogMessage(class, load) msg;
3309 stringStream info_stream;
3310
3311 // Name and class hierarchy info
3312 info_stream.print("%s", external_name());
3313
3314 // Source
3315 if (cfs != NULL) {
3316 if (cfs->source() != NULL) {
3317 if (module_name != NULL) {
3318 if (ClassLoader::is_jrt(cfs->source())) {
3319 info_stream.print(" source: jrt:/%s", module_name);
3320 } else {
3321 info_stream.print(" source: %s", cfs->source());
3322 }
3323 } else {
3324 info_stream.print(" source: %s", cfs->source());
3325 }
3326 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3327 Thread* THREAD = Thread::current();
3328 Klass* caller =
3329 THREAD->is_Java_thread()
3330 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3331 : NULL;
3332 // caller can be NULL, for example, during a JVMTI VM_Init hook
3333 if (caller != NULL) {
3334 info_stream.print(" source: instance of %s", caller->external_name());
3335 } else {
3336 // source is unknown
3337 }
3338 } else {
3339 oop class_loader = loader_data->class_loader();
3340 info_stream.print(" source: %s", class_loader->klass()->external_name());
3341 }
3342 } else {
3343 info_stream.print(" source: shared objects file");
3344 }
3345
3346 msg.info("%s", info_stream.as_string());
3347
3348 if (log_is_enabled(Debug, class, load)) {
3349 stringStream debug_stream;
3350
3351 // Class hierarchy info
3352 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3353 p2i(this), p2i(superklass()));
3354
3355 // Interfaces
3356 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3357 debug_stream.print(" interfaces:");
3358 int length = local_interfaces()->length();
3359 for (int i = 0; i < length; i++) {
3360 debug_stream.print(" " INTPTR_FORMAT,
3361 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3362 }
3363 }
3364
3365 // Class loader
3366 debug_stream.print(" loader: [");
3367 loader_data->print_value_on(&debug_stream);
3368 debug_stream.print("]");
3369
3370 // Classfile checksum
3371 if (cfs) {
3372 debug_stream.print(" bytes: %d checksum: %08x",
3373 cfs->length(),
3374 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3375 cfs->length()));
3376 }
3377
3378 msg.debug("%s", debug_stream.as_string());
3379 }
3380 }
3381
3382 #if INCLUDE_SERVICES
3383 // Size Statistics
3384 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3385 Klass::collect_statistics(sz);
3386
3387 sz->_inst_size = wordSize * size_helper();
3388 sz->_vtab_bytes = wordSize * vtable_length();
3389 sz->_itab_bytes = wordSize * itable_length();
3390 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3391
3392 int n = 0;
3393 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3394 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3395 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3396 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3397 n += (sz->_fields_bytes = sz->count_array(fields()));
3398 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3399 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3400 sz->_ro_bytes += n;
3401
3402 const ConstantPool* cp = constants();
3403 if (cp) {
3404 cp->collect_statistics(sz);
3405 }
3406
3407 const Annotations* anno = annotations();
3408 if (anno) {
3409 anno->collect_statistics(sz);
3410 }
3411
3412 const Array<Method*>* methods_array = methods();
3413 if (methods()) {
3414 for (int i = 0; i < methods_array->length(); i++) {
3415 Method* method = methods_array->at(i);
3416 if (method) {
3417 sz->_method_count ++;
3418 method->collect_statistics(sz);
3419 }
3420 }
3421 }
3422 }
3423 #endif // INCLUDE_SERVICES
3424
3425 // Verification
3426
3427 class VerifyFieldClosure: public OopClosure {
3428 protected:
3429 template <class T> void do_oop_work(T* p) {
3430 oop obj = oopDesc::load_decode_heap_oop(p);
3431 if (!oopDesc::is_oop_or_null(obj)) {
3432 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3433 Universe::print_on(tty);
3434 guarantee(false, "boom");
3435 }
3436 }
3437 public:
3438 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3439 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3440 };
3441
3442 void InstanceKlass::verify_on(outputStream* st) {
3443 #ifndef PRODUCT
3444 // Avoid redundant verifies, this really should be in product.
3445 if (_verify_count == Universe::verify_count()) return;
3446 _verify_count = Universe::verify_count();
3447 #endif
3448
3449 // Verify Klass
3450 Klass::verify_on(st);
3451
3452 // Verify that klass is present in ClassLoaderData
3453 guarantee(class_loader_data()->contains_klass(this),
3454 "this class isn't found in class loader data");
3455
3456 // Verify vtables
3457 if (is_linked()) {
3458 // $$$ This used to be done only for m/s collections. Doing it
3459 // always seemed a valid generalization. (DLD -- 6/00)
3460 vtable().verify(st);
3461 }
3462
3463 // Verify first subklass
3464 if (subklass() != NULL) {
3465 guarantee(subklass()->is_klass(), "should be klass");
3466 }
3467
3468 // Verify siblings
3469 Klass* super = this->super();
3470 Klass* sib = next_sibling();
3471 if (sib != NULL) {
3472 if (sib == this) {
3473 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3474 }
3475
3476 guarantee(sib->is_klass(), "should be klass");
3477 guarantee(sib->super() == super, "siblings should have same superklass");
3478 }
3479
3480 // Verify implementor fields
3481 Klass* im = implementor();
3482 if (im != NULL) {
3483 guarantee(is_interface(), "only interfaces should have implementor set");
3484 guarantee(im->is_klass(), "should be klass");
3485 guarantee(!im->is_interface() || im == this,
3486 "implementors cannot be interfaces");
3487 }
3488
3489 // Verify local interfaces
3490 if (local_interfaces()) {
3491 Array<Klass*>* local_interfaces = this->local_interfaces();
3492 for (int j = 0; j < local_interfaces->length(); j++) {
3493 Klass* e = local_interfaces->at(j);
3494 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3495 }
3496 }
3497
3498 // Verify transitive interfaces
3499 if (transitive_interfaces() != NULL) {
3500 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3501 for (int j = 0; j < transitive_interfaces->length(); j++) {
3502 Klass* e = transitive_interfaces->at(j);
3503 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3504 }
3505 }
3506
3507 // Verify methods
3508 if (methods() != NULL) {
3509 Array<Method*>* methods = this->methods();
3510 for (int j = 0; j < methods->length(); j++) {
3511 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3512 }
3513 for (int j = 0; j < methods->length() - 1; j++) {
3514 Method* m1 = methods->at(j);
3515 Method* m2 = methods->at(j + 1);
3516 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3517 }
3518 }
3519
3520 // Verify method ordering
3521 if (method_ordering() != NULL) {
3522 Array<int>* method_ordering = this->method_ordering();
3523 int length = method_ordering->length();
3524 if (JvmtiExport::can_maintain_original_method_order() ||
3525 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3526 guarantee(length == methods()->length(), "invalid method ordering length");
3527 jlong sum = 0;
3528 for (int j = 0; j < length; j++) {
3529 int original_index = method_ordering->at(j);
3530 guarantee(original_index >= 0, "invalid method ordering index");
3531 guarantee(original_index < length, "invalid method ordering index");
3532 sum += original_index;
3533 }
3534 // Verify sum of indices 0,1,...,length-1
3535 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3536 } else {
3537 guarantee(length == 0, "invalid method ordering length");
3538 }
3539 }
3540
3541 // Verify default methods
3542 if (default_methods() != NULL) {
3543 Array<Method*>* methods = this->default_methods();
3544 for (int j = 0; j < methods->length(); j++) {
3545 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3546 }
3547 for (int j = 0; j < methods->length() - 1; j++) {
3548 Method* m1 = methods->at(j);
3549 Method* m2 = methods->at(j + 1);
3550 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3551 }
3552 }
3553
3554 // Verify JNI static field identifiers
3555 if (jni_ids() != NULL) {
3556 jni_ids()->verify(this);
3557 }
3558
3559 // Verify other fields
3560 if (array_klasses() != NULL) {
3561 guarantee(array_klasses()->is_klass(), "should be klass");
3562 }
3563 if (constants() != NULL) {
3564 guarantee(constants()->is_constantPool(), "should be constant pool");
3565 }
3566 const Klass* host = host_klass();
3567 if (host != NULL) {
3568 guarantee(host->is_klass(), "should be klass");
3569 }
3570 }
3571
3572 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3573 Klass::oop_verify_on(obj, st);
3574 VerifyFieldClosure blk;
3575 obj->oop_iterate_no_header(&blk);
3576 }
3577
3578
3579 // JNIid class for jfieldIDs only
3580 // Note to reviewers:
3581 // These JNI functions are just moved over to column 1 and not changed
3582 // in the compressed oops workspace.
3583 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3584 _holder = holder;
3585 _offset = offset;
3586 _next = next;
3587 debug_only(_is_static_field_id = false;)
3588 }
3589
3590
3591 JNIid* JNIid::find(int offset) {
3592 JNIid* current = this;
3593 while (current != NULL) {
3594 if (current->offset() == offset) return current;
3595 current = current->next();
3596 }
3597 return NULL;
3598 }
3599
3600 void JNIid::deallocate(JNIid* current) {
3601 while (current != NULL) {
3602 JNIid* next = current->next();
3603 delete current;
3604 current = next;
3605 }
3606 }
3607
3608
3609 void JNIid::verify(Klass* holder) {
3610 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3611 int end_field_offset;
3612 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3613
3614 JNIid* current = this;
3615 while (current != NULL) {
3616 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3617 #ifdef ASSERT
3618 int o = current->offset();
3619 if (current->is_static_field_id()) {
3620 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3621 }
3622 #endif
3623 current = current->next();
3624 }
3625 }
3626
3627
3628 #ifdef ASSERT
3629 void InstanceKlass::set_init_state(ClassState state) {
3630 bool good_state = is_shared() ? (_init_state <= state)
3631 : (_init_state < state);
3632 assert(good_state || state == allocated, "illegal state transition");
3633 _init_state = (u1)state;
3634 }
3635 #endif
3636
3637 #if INCLUDE_JVMTI
3638
3639 // RedefineClasses() support for previous versions
3640
3641 // Globally, there is at least one previous version of a class to walk
3642 // during class unloading, which is saved because old methods in the class
3643 // are still running. Otherwise the previous version list is cleaned up.
3644 bool InstanceKlass::_has_previous_versions = false;
3645
3646 // Returns true if there are previous versions of a class for class
3647 // unloading only. Also resets the flag to false. purge_previous_version
3648 // will set the flag to true if there are any left, i.e., if there's any
3649 // work to do for next time. This is to avoid the expensive code cache
3650 // walk in CLDG::do_unloading().
3651 bool InstanceKlass::has_previous_versions_and_reset() {
3652 bool ret = _has_previous_versions;
3653 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3654 ret ? "true" : "false");
3655 _has_previous_versions = false;
3656 return ret;
3657 }
3658
3659 // Purge previous versions before adding new previous versions of the class and
3660 // during class unloading.
3661 void InstanceKlass::purge_previous_version_list() {
3662 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3663 assert(has_been_redefined(), "Should only be called for main class");
3664
3665 // Quick exit.
3666 if (previous_versions() == NULL) {
3667 return;
3668 }
3669
3670 // This klass has previous versions so see what we can cleanup
3671 // while it is safe to do so.
3672
3673 int deleted_count = 0; // leave debugging breadcrumbs
3674 int live_count = 0;
3675 ClassLoaderData* loader_data = class_loader_data();
3676 assert(loader_data != NULL, "should never be null");
3677
3678 ResourceMark rm;
3679 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3680
3681 // previous versions are linked together through the InstanceKlass
3682 InstanceKlass* pv_node = previous_versions();
3683 InstanceKlass* last = this;
3684 int version = 0;
3685
3686 // check the previous versions list
3687 for (; pv_node != NULL; ) {
3688
3689 ConstantPool* pvcp = pv_node->constants();
3690 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3691
3692 if (!pvcp->on_stack()) {
3693 // If the constant pool isn't on stack, none of the methods
3694 // are executing. Unlink this previous_version.
3695 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3696 // so will be deallocated during the next phase of class unloading.
3697 log_trace(redefine, class, iklass, purge)
3698 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3699 // For debugging purposes.
3700 pv_node->set_is_scratch_class();
3701 // Unlink from previous version list.
3702 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3703 InstanceKlass* next = pv_node->previous_versions();
3704 pv_node->link_previous_versions(NULL); // point next to NULL
3705 last->link_previous_versions(next);
3706 // Add to the deallocate list after unlinking
3707 loader_data->add_to_deallocate_list(pv_node);
3708 pv_node = next;
3709 deleted_count++;
3710 version++;
3711 continue;
3712 } else {
3713 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3714 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3715 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3716 live_count++;
3717 // found a previous version for next time we do class unloading
3718 _has_previous_versions = true;
3719 }
3720
3721 // At least one method is live in this previous version.
3722 // Reset dead EMCP methods not to get breakpoints.
3723 // All methods are deallocated when all of the methods for this class are no
3724 // longer running.
3725 Array<Method*>* method_refs = pv_node->methods();
3726 if (method_refs != NULL) {
3727 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3728 for (int j = 0; j < method_refs->length(); j++) {
3729 Method* method = method_refs->at(j);
3730
3731 if (!method->on_stack()) {
3732 // no breakpoints for non-running methods
3733 if (method->is_running_emcp()) {
3734 method->set_running_emcp(false);
3735 }
3736 } else {
3737 assert (method->is_obsolete() || method->is_running_emcp(),
3738 "emcp method cannot run after emcp bit is cleared");
3739 log_trace(redefine, class, iklass, purge)
3740 ("purge: %s(%s): prev method @%d in version @%d is alive",
3741 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3742 }
3743 }
3744 }
3745 // next previous version
3746 last = pv_node;
3747 pv_node = pv_node->previous_versions();
3748 version++;
3749 }
3750 log_trace(redefine, class, iklass, purge)
3751 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3752 }
3753
3754 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3755 int emcp_method_count) {
3756 int obsolete_method_count = old_methods->length() - emcp_method_count;
3757
3758 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3759 _previous_versions != NULL) {
3760 // We have a mix of obsolete and EMCP methods so we have to
3761 // clear out any matching EMCP method entries the hard way.
3762 int local_count = 0;
3763 for (int i = 0; i < old_methods->length(); i++) {
3764 Method* old_method = old_methods->at(i);
3765 if (old_method->is_obsolete()) {
3766 // only obsolete methods are interesting
3767 Symbol* m_name = old_method->name();
3768 Symbol* m_signature = old_method->signature();
3769
3770 // previous versions are linked together through the InstanceKlass
3771 int j = 0;
3772 for (InstanceKlass* prev_version = _previous_versions;
3773 prev_version != NULL;
3774 prev_version = prev_version->previous_versions(), j++) {
3775
3776 Array<Method*>* method_refs = prev_version->methods();
3777 for (int k = 0; k < method_refs->length(); k++) {
3778 Method* method = method_refs->at(k);
3779
3780 if (!method->is_obsolete() &&
3781 method->name() == m_name &&
3782 method->signature() == m_signature) {
3783 // The current RedefineClasses() call has made all EMCP
3784 // versions of this method obsolete so mark it as obsolete
3785 log_trace(redefine, class, iklass, add)
3786 ("%s(%s): flush obsolete method @%d in version @%d",
3787 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3788
3789 method->set_is_obsolete();
3790 break;
3791 }
3792 }
3793
3794 // The previous loop may not find a matching EMCP method, but
3795 // that doesn't mean that we can optimize and not go any
3796 // further back in the PreviousVersion generations. The EMCP
3797 // method for this generation could have already been made obsolete,
3798 // but there still may be an older EMCP method that has not
3799 // been made obsolete.
3800 }
3801
3802 if (++local_count >= obsolete_method_count) {
3803 // no more obsolete methods so bail out now
3804 break;
3805 }
3806 }
3807 }
3808 }
3809 }
3810
3811 // Save the scratch_class as the previous version if any of the methods are running.
3812 // The previous_versions are used to set breakpoints in EMCP methods and they are
3813 // also used to clean MethodData links to redefined methods that are no longer running.
3814 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3815 int emcp_method_count) {
3816 assert(Thread::current()->is_VM_thread(),
3817 "only VMThread can add previous versions");
3818
3819 ResourceMark rm;
3820 log_trace(redefine, class, iklass, add)
3821 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3822
3823 // Clean out old previous versions for this class
3824 purge_previous_version_list();
3825
3826 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3827 // a previous redefinition may be made obsolete by this redefinition.
3828 Array<Method*>* old_methods = scratch_class->methods();
3829 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3830
3831 // If the constant pool for this previous version of the class
3832 // is not marked as being on the stack, then none of the methods
3833 // in this previous version of the class are on the stack so
3834 // we don't need to add this as a previous version.
3835 ConstantPool* cp_ref = scratch_class->constants();
3836 if (!cp_ref->on_stack()) {
3837 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3838 // For debugging purposes.
3839 scratch_class->set_is_scratch_class();
3840 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3841 return;
3842 }
3843
3844 if (emcp_method_count != 0) {
3845 // At least one method is still running, check for EMCP methods
3846 for (int i = 0; i < old_methods->length(); i++) {
3847 Method* old_method = old_methods->at(i);
3848 if (!old_method->is_obsolete() && old_method->on_stack()) {
3849 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3850 // we can add breakpoints for it.
3851
3852 // We set the method->on_stack bit during safepoints for class redefinition
3853 // and use this bit to set the is_running_emcp bit.
3854 // After the safepoint, the on_stack bit is cleared and the running emcp
3855 // method may exit. If so, we would set a breakpoint in a method that
3856 // is never reached, but this won't be noticeable to the programmer.
3857 old_method->set_running_emcp(true);
3858 log_trace(redefine, class, iklass, add)
3859 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3860 } else if (!old_method->is_obsolete()) {
3861 log_trace(redefine, class, iklass, add)
3862 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3863 }
3864 }
3865 }
3866
3867 // Add previous version if any methods are still running.
3868 // Set has_previous_version flag for processing during class unloading.
3869 _has_previous_versions = true;
3870 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3871 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3872 scratch_class->link_previous_versions(previous_versions());
3873 link_previous_versions(scratch_class);
3874 } // end add_previous_version()
3875
3876 #endif // INCLUDE_JVMTI
3877
3878 Method* InstanceKlass::method_with_idnum(int idnum) {
3879 Method* m = NULL;
3880 if (idnum < methods()->length()) {
3881 m = methods()->at(idnum);
3882 }
3883 if (m == NULL || m->method_idnum() != idnum) {
3884 for (int index = 0; index < methods()->length(); ++index) {
3885 m = methods()->at(index);
3886 if (m->method_idnum() == idnum) {
3887 return m;
3888 }
3889 }
3890 // None found, return null for the caller to handle.
3891 return NULL;
3892 }
3893 return m;
3894 }
3895
3896
3897 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3898 if (idnum >= methods()->length()) {
3899 return NULL;
3900 }
3901 Method* m = methods()->at(idnum);
3902 if (m != NULL && m->orig_method_idnum() == idnum) {
3903 return m;
3904 }
3905 // Obsolete method idnum does not match the original idnum
3906 for (int index = 0; index < methods()->length(); ++index) {
3907 m = methods()->at(index);
3908 if (m->orig_method_idnum() == idnum) {
3909 return m;
3910 }
3911 }
3912 // None found, return null for the caller to handle.
3913 return NULL;
3914 }
3915
3916
3917 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3918 InstanceKlass* holder = get_klass_version(version);
3919 if (holder == NULL) {
3920 return NULL; // The version of klass is gone, no method is found
3921 }
3922 Method* method = holder->method_with_orig_idnum(idnum);
3923 return method;
3924 }
3925
3926 #if INCLUDE_JVMTI
3927 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3928 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3929 // Ignore the archived class stream data
3930 return NULL;
3931 } else {
3932 return _cached_class_file;
3933 }
3934 }
3935
3936 jint InstanceKlass::get_cached_class_file_len() {
3937 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3938 }
3939
3940 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3941 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3942 }
3943
3944 #if INCLUDE_CDS
3945 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3946 if (DumpSharedSpaces) {
3947 return _cached_class_file;
3948 } else {
3949 assert(this->is_shared(), "class should be shared");
3950 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3951 return _cached_class_file;
3952 } else {
3953 return NULL;
3954 }
3955 }
3956 }
3957 #endif
3958 #endif