1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/verifier.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/dependencyContext.hpp"
39 #include "compiler/compileBroker.hpp"
40 #include "gc/shared/collectedHeap.inline.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/heapInspection.hpp"
49 #include "memory/iterator.inline.hpp"
50 #include "memory/metadataFactory.hpp"
51 #include "memory/metaspaceClosure.hpp"
52 #include "memory/metaspaceShared.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "oops/fieldStreams.hpp"
56 #include "oops/instanceClassLoaderKlass.hpp"
57 #include "oops/instanceKlass.inline.hpp"
58 #include "oops/instanceMirrorKlass.hpp"
59 #include "oops/instanceOop.hpp"
60 #include "oops/klass.inline.hpp"
61 #include "oops/method.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.inline.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83 #if INCLUDE_JFR
84 #include "jfr/jfrEvents.hpp"
85 #endif
86
87
88 #ifdef DTRACE_ENABLED
89
90
91 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
92 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
93 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
94 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
95 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
96 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
97 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
98 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
99 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
100 { \
101 char* data = NULL; \
102 int len = 0; \
103 Symbol* clss_name = name(); \
104 if (clss_name != NULL) { \
105 data = (char*)clss_name->bytes(); \
106 len = clss_name->utf8_length(); \
107 } \
108 HOTSPOT_CLASS_INITIALIZATION_##type( \
109 data, len, (void*)class_loader(), thread_type); \
110 }
111
112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
113 { \
114 char* data = NULL; \
115 int len = 0; \
116 Symbol* clss_name = name(); \
117 if (clss_name != NULL) { \
118 data = (char*)clss_name->bytes(); \
119 len = clss_name->utf8_length(); \
120 } \
121 HOTSPOT_CLASS_INITIALIZATION_##type( \
122 data, len, (void*)class_loader(), thread_type, wait); \
123 }
124
125 #else // ndef DTRACE_ENABLED
126
127 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
128 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
129
130 #endif // ndef DTRACE_ENABLED
131
132 static inline bool is_class_loader(const Symbol* class_name,
133 const ClassFileParser& parser) {
134 assert(class_name != NULL, "invariant");
135
136 if (class_name == vmSymbols::java_lang_ClassLoader()) {
137 return true;
138 }
139
140 if (SystemDictionary::ClassLoader_klass_loaded()) {
141 const Klass* const super_klass = parser.super_klass();
142 if (super_klass != NULL) {
143 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
144 return true;
145 }
146 }
147 }
148 return false;
149 }
150
151 // called to verify that k is a member of this nest
152 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
153 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
154 if (log_is_enabled(Trace, class, nestmates)) {
155 ResourceMark rm(THREAD);
156 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
157 k->external_name(), this->external_name());
158 }
159 return false;
160 }
161
162 if (log_is_enabled(Trace, class, nestmates)) {
163 ResourceMark rm(THREAD);
164 log_trace(class, nestmates)("Checking nest membership of %s in %s",
165 k->external_name(), this->external_name());
166 }
167
168 // Check names first and if they match then check actual klass. This avoids
169 // resolving anything unnecessarily.
170 for (int i = 0; i < _nest_members->length(); i++) {
171 int cp_index = _nest_members->at(i);
172 Symbol* name = _constants->klass_name_at(cp_index);
173 if (name == k->name()) {
174 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
175
176 // names match so check actual klass - this may trigger class loading if
177 // it doesn't match (but that should be impossible)
178 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
179 if (k2 == k) {
180 log_trace(class, nestmates)("- class is listed as a nest member");
181 return true;
182 } else {
183 // same name but different klass!
184 log_trace(class, nestmates)(" - klass comparison failed!");
185 // can't have different classes for the same name, so we're done
186 return false;
187 }
188 }
189 }
190 log_trace(class, nestmates)("- class is NOT a nest member!");
191 return false;
192 }
193
194 // Return nest-host class, resolving, validating and saving it if needed.
195 // In cases where this is called from a thread that can not do classloading
196 // (such as a native JIT thread) then we simply return NULL, which in turn
197 // causes the access check to return false. Such code will retry the access
198 // from a more suitable environment later.
199 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
200 InstanceKlass* nest_host_k = _nest_host;
201 if (nest_host_k == NULL) {
202 // need to resolve and save our nest-host class. This could be attempted
203 // concurrently but as the result is idempotent and we don't use the class
204 // then we do not need any synchronization beyond what is implicitly used
205 // during class loading.
206 if (_nest_host_index != 0) { // we have a real nest_host
207 // Before trying to resolve check if we're in a suitable context
208 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
209 if (log_is_enabled(Trace, class, nestmates)) {
210 ResourceMark rm(THREAD);
211 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
212 this->external_name());
213 }
214 return NULL;
215 }
216
217 if (log_is_enabled(Trace, class, nestmates)) {
218 ResourceMark rm(THREAD);
219 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
220 this->external_name(),
221 _constants->klass_name_at(_nest_host_index)->as_C_string());
222 }
223
224 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
225 if (HAS_PENDING_EXCEPTION) {
226 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
227 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
228 // throw a new CDNFE with the original as its cause, and a clear msg
229 ResourceMark rm(THREAD);
230 char buf[200];
231 CLEAR_PENDING_EXCEPTION;
232 jio_snprintf(buf, sizeof(buf),
233 "Unable to load nest-host class (%s) of %s",
234 _constants->klass_name_at(_nest_host_index)->as_C_string(),
235 this->external_name());
236 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
237 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
238 }
239 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
240 return NULL;
241 }
242
243 // A valid nest-host is an instance class in the current package that lists this
244 // class as a nest member. If any of these conditions are not met we post the
245 // requested exception type (if any) and return NULL
246
247 const char* error = NULL;
248
249 // JVMS 5.4.4 indicates package check comes first
250 if (is_same_class_package(k)) {
251
252 // Now check actual membership. We can't be a member if our "host" is
253 // not an instance class.
254 if (k->is_instance_klass()) {
255 nest_host_k = InstanceKlass::cast(k);
256
257 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
258 if (is_member) {
259 // save resolved nest-host value
260 _nest_host = nest_host_k;
261
262 if (log_is_enabled(Trace, class, nestmates)) {
263 ResourceMark rm(THREAD);
264 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
265 this->external_name(), k->external_name());
266 }
267 return nest_host_k;
268 }
269 }
270 error = "current type is not listed as a nest member";
271 } else {
272 error = "types are in different packages";
273 }
274
275 if (log_is_enabled(Trace, class, nestmates)) {
276 ResourceMark rm(THREAD);
277 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
278 this->external_name(),
279 k->external_name(),
280 error);
281 }
282
283 if (validationException != NULL) {
284 ResourceMark rm(THREAD);
285 Exceptions::fthrow(THREAD_AND_LOCATION,
286 validationException,
287 "Type %s is not a nest member of %s: %s",
288 this->external_name(),
289 k->external_name(),
290 error
291 );
292 }
293 return NULL;
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 JVMS 5.4.4 we first resolve and validate the current class, then
315 // the target class k. Resolution exceptions will be passed on by upper
316 // layers. IncompatibleClassChangeErrors from membership validation failures
317 // will also be passed through.
318
319 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
320 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
321 if (cur_host == NULL) {
322 return false;
323 }
324
325 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
326 if (k_nest_host == NULL) {
327 return false;
328 }
329
330 bool access = (cur_host == k_nest_host);
331
332 if (log_is_enabled(Trace, class, nestmates)) {
333 ResourceMark rm(THREAD);
334 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
335 this->external_name(),
336 access ? "" : "NOT ",
337 k->external_name());
338 }
339
340 return access;
341 }
342
343 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
344 const int size = InstanceKlass::size(parser.vtable_size(),
345 parser.itable_size(),
346 nonstatic_oop_map_size(parser.total_oop_map_count()),
347 parser.is_interface(),
348 parser.is_unsafe_anonymous(),
349 should_store_fingerprint(parser.is_unsafe_anonymous()));
350
351 const Symbol* const class_name = parser.class_name();
352 assert(class_name != NULL, "invariant");
353 ClassLoaderData* loader_data = parser.loader_data();
354 assert(loader_data != NULL, "invariant");
355
356 InstanceKlass* ik;
357
358 // Allocation
359 if (REF_NONE == parser.reference_type()) {
360 if (class_name == vmSymbols::java_lang_Class()) {
361 // mirror
362 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
363 }
364 else if (is_class_loader(class_name, parser)) {
365 // class loader
366 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
367 } else {
368 // normal
369 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
370 }
371 } else {
372 // reference
373 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
374 }
375
376 // Check for pending exception before adding to the loader data and incrementing
377 // class count. Can get OOM here.
378 if (HAS_PENDING_EXCEPTION) {
379 return NULL;
380 }
381
382 return ik;
383 }
384
385
386 // copy method ordering from resource area to Metaspace
387 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
388 if (m != NULL) {
389 // allocate a new array and copy contents (memcpy?)
390 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
391 for (int i = 0; i < m->length(); i++) {
392 _method_ordering->at_put(i, m->at(i));
393 }
394 } else {
395 _method_ordering = Universe::the_empty_int_array();
396 }
397 }
398
399 // create a new array of vtable_indices for default methods
400 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
401 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
402 assert(default_vtable_indices() == NULL, "only create once");
403 set_default_vtable_indices(vtable_indices);
404 return vtable_indices;
405 }
406
407 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
408 Klass(id),
409 _nest_members(NULL),
410 _nest_host_index(0),
411 _nest_host(NULL),
412 _static_field_size(parser.static_field_size()),
413 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
414 _itable_len(parser.itable_size()),
415 _reference_type(parser.reference_type()) {
416 set_vtable_length(parser.vtable_size());
417 set_kind(kind);
418 set_access_flags(parser.access_flags());
419 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
420 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
421 false));
422
423 assert(NULL == _methods, "underlying memory not zeroed?");
424 assert(is_instance_klass(), "is layout incorrect?");
425 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
426 }
427
428 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
429 Array<Method*>* methods) {
430 if (methods != NULL && methods != Universe::the_empty_method_array() &&
431 !methods->is_shared()) {
432 for (int i = 0; i < methods->length(); i++) {
433 Method* method = methods->at(i);
434 if (method == NULL) continue; // maybe null if error processing
435 // Only want to delete methods that are not executing for RedefineClasses.
436 // The previous version will point to them so they're not totally dangling
437 assert (!method->on_stack(), "shouldn't be called with methods on stack");
438 MetadataFactory::free_metadata(loader_data, method);
439 }
440 MetadataFactory::free_array<Method*>(loader_data, methods);
441 }
442 }
443
444 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
445 const Klass* super_klass,
446 Array<InstanceKlass*>* local_interfaces,
447 Array<InstanceKlass*>* transitive_interfaces) {
448 // Only deallocate transitive interfaces if not empty, same as super class
449 // or same as local interfaces. See code in parseClassFile.
450 Array<InstanceKlass*>* ti = transitive_interfaces;
451 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
452 // check that the interfaces don't come from super class
453 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
454 InstanceKlass::cast(super_klass)->transitive_interfaces();
455 if (ti != sti && ti != NULL && !ti->is_shared()) {
456 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
457 }
458 }
459
460 // local interfaces can be empty
461 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
462 local_interfaces != NULL && !local_interfaces->is_shared()) {
463 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
464 }
465 }
466
467 // This function deallocates the metadata and C heap pointers that the
468 // InstanceKlass points to.
469 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
470
471 // Orphan the mirror first, CMS thinks it's still live.
472 if (java_mirror() != NULL) {
473 java_lang_Class::set_klass(java_mirror(), NULL);
474 }
475
476 // Also remove mirror from handles
477 loader_data->remove_handle(_java_mirror);
478
479 // Need to take this class off the class loader data list.
480 loader_data->remove_class(this);
481
482 // The array_klass for this class is created later, after error handling.
483 // For class redefinition, we keep the original class so this scratch class
484 // doesn't have an array class. Either way, assert that there is nothing
485 // to deallocate.
486 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
487
488 // Release C heap allocated data that this might point to, which includes
489 // reference counting symbol names.
490 release_C_heap_structures();
491
492 deallocate_methods(loader_data, methods());
493 set_methods(NULL);
494
495 if (method_ordering() != NULL &&
496 method_ordering() != Universe::the_empty_int_array() &&
497 !method_ordering()->is_shared()) {
498 MetadataFactory::free_array<int>(loader_data, method_ordering());
499 }
500 set_method_ordering(NULL);
501
502 // default methods can be empty
503 if (default_methods() != NULL &&
504 default_methods() != Universe::the_empty_method_array() &&
505 !default_methods()->is_shared()) {
506 MetadataFactory::free_array<Method*>(loader_data, default_methods());
507 }
508 // Do NOT deallocate the default methods, they are owned by superinterfaces.
509 set_default_methods(NULL);
510
511 // default methods vtable indices can be empty
512 if (default_vtable_indices() != NULL &&
513 !default_vtable_indices()->is_shared()) {
514 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
515 }
516 set_default_vtable_indices(NULL);
517
518
519 // This array is in Klass, but remove it with the InstanceKlass since
520 // this place would be the only caller and it can share memory with transitive
521 // interfaces.
522 if (secondary_supers() != NULL &&
523 secondary_supers() != Universe::the_empty_klass_array() &&
524 // see comments in compute_secondary_supers about the following cast
525 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
526 !secondary_supers()->is_shared()) {
527 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
528 }
529 set_secondary_supers(NULL);
530
531 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
532 set_transitive_interfaces(NULL);
533 set_local_interfaces(NULL);
534
535 if (fields() != NULL && !fields()->is_shared()) {
536 MetadataFactory::free_array<jushort>(loader_data, fields());
537 }
538 set_fields(NULL, 0);
539
540 // If a method from a redefined class is using this constant pool, don't
541 // delete it, yet. The new class's previous version will point to this.
542 if (constants() != NULL) {
543 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
544 if (!constants()->is_shared()) {
545 MetadataFactory::free_metadata(loader_data, constants());
546 }
547 // Delete any cached resolution errors for the constant pool
548 SystemDictionary::delete_resolution_error(constants());
549
550 set_constants(NULL);
551 }
552
553 if (inner_classes() != NULL &&
554 inner_classes() != Universe::the_empty_short_array() &&
555 !inner_classes()->is_shared()) {
556 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
557 }
558 set_inner_classes(NULL);
559
560 if (nest_members() != NULL &&
561 nest_members() != Universe::the_empty_short_array() &&
562 !nest_members()->is_shared()) {
563 MetadataFactory::free_array<jushort>(loader_data, nest_members());
564 }
565 set_nest_members(NULL);
566
567 // We should deallocate the Annotations instance if it's not in shared spaces.
568 if (annotations() != NULL && !annotations()->is_shared()) {
569 MetadataFactory::free_metadata(loader_data, annotations());
570 }
571 set_annotations(NULL);
572 }
573
574 bool InstanceKlass::should_be_initialized() const {
575 return !is_initialized();
576 }
577
578 klassItable InstanceKlass::itable() const {
579 return klassItable(const_cast<InstanceKlass*>(this));
580 }
581
582 void InstanceKlass::eager_initialize(Thread *thread) {
583 if (!EagerInitialization) return;
584
585 if (this->is_not_initialized()) {
586 // abort if the the class has a class initializer
587 if (this->class_initializer() != NULL) return;
588
589 // abort if it is java.lang.Object (initialization is handled in genesis)
590 Klass* super_klass = super();
591 if (super_klass == NULL) return;
592
593 // abort if the super class should be initialized
594 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
595
596 // call body to expose the this pointer
597 eager_initialize_impl();
598 }
599 }
600
601 // JVMTI spec thinks there are signers and protection domain in the
602 // instanceKlass. These accessors pretend these fields are there.
603 // The hprof specification also thinks these fields are in InstanceKlass.
604 oop InstanceKlass::protection_domain() const {
605 // return the protection_domain from the mirror
606 return java_lang_Class::protection_domain(java_mirror());
607 }
608
609 // To remove these from requires an incompatible change and CCC request.
610 objArrayOop InstanceKlass::signers() const {
611 // return the signers from the mirror
612 return java_lang_Class::signers(java_mirror());
613 }
614
615 oop InstanceKlass::init_lock() const {
616 // return the init lock from the mirror
617 oop lock = java_lang_Class::init_lock(java_mirror());
618 // Prevent reordering with any access of initialization state
619 OrderAccess::loadload();
620 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
621 "only fully initialized state can have a null lock");
622 return lock;
623 }
624
625 // Set the initialization lock to null so the object can be GC'ed. Any racing
626 // threads to get this lock will see a null lock and will not lock.
627 // That's okay because they all check for initialized state after getting
628 // the lock and return.
629 void InstanceKlass::fence_and_clear_init_lock() {
630 // make sure previous stores are all done, notably the init_state.
631 OrderAccess::storestore();
632 java_lang_Class::set_init_lock(java_mirror(), NULL);
633 assert(!is_not_initialized(), "class must be initialized now");
634 }
635
636 void InstanceKlass::eager_initialize_impl() {
637 EXCEPTION_MARK;
638 HandleMark hm(THREAD);
639 Handle h_init_lock(THREAD, init_lock());
640 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
641
642 // abort if someone beat us to the initialization
643 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
644
645 ClassState old_state = init_state();
646 link_class_impl(THREAD);
647 if (HAS_PENDING_EXCEPTION) {
648 CLEAR_PENDING_EXCEPTION;
649 // Abort if linking the class throws an exception.
650
651 // Use a test to avoid redundantly resetting the state if there's
652 // no change. Set_init_state() asserts that state changes make
653 // progress, whereas here we might just be spinning in place.
654 if (old_state != _init_state)
655 set_init_state(old_state);
656 } else {
657 // linking successfull, mark class as initialized
658 set_init_state(fully_initialized);
659 fence_and_clear_init_lock();
660 // trace
661 if (log_is_enabled(Info, class, init)) {
662 ResourceMark rm(THREAD);
663 log_info(class, init)("[Initialized %s without side effects]", external_name());
664 }
665 }
666 }
667
668
669 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
670 // process. The step comments refers to the procedure described in that section.
671 // Note: implementation moved to static method to expose the this pointer.
672 void InstanceKlass::initialize(TRAPS) {
673 if (this->should_be_initialized()) {
674 initialize_impl(CHECK);
675 // Note: at this point the class may be initialized
676 // OR it may be in the state of being initialized
677 // in case of recursive initialization!
678 } else {
679 assert(is_initialized(), "sanity check");
680 }
681 }
682
683
684 bool InstanceKlass::verify_code(TRAPS) {
685 // 1) Verify the bytecodes
686 return Verifier::verify(this, should_verify_class(), THREAD);
687 }
688
689
690 // Used exclusively by the shared spaces dump mechanism to prevent
691 // classes mapped into the shared regions in new VMs from appearing linked.
692
693 void InstanceKlass::unlink_class() {
694 assert(is_linked(), "must be linked");
695 _init_state = loaded;
696 }
697
698 void InstanceKlass::link_class(TRAPS) {
699 assert(is_loaded(), "must be loaded");
700 if (!is_linked()) {
701 link_class_impl(CHECK);
702 }
703 }
704
705 // Called to verify that a class can link during initialization, without
706 // throwing a VerifyError.
707 bool InstanceKlass::link_class_or_fail(TRAPS) {
708 assert(is_loaded(), "must be loaded");
709 if (!is_linked()) {
710 link_class_impl(CHECK_false);
711 }
712 return is_linked();
713 }
714
715 bool InstanceKlass::link_class_impl(TRAPS) {
716 if (DumpSharedSpaces && is_in_error_state()) {
717 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
718 // the class has failed verification. Throwing the NoClassDefFoundError here is just
719 // a convenient way to stop repeat attempts to verify the same (bad) class.
720 //
721 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
722 // if we are executing Java code. This is not a problem for CDS dumping phase since
723 // it doesn't execute any Java code.
724 ResourceMark rm(THREAD);
725 Exceptions::fthrow(THREAD_AND_LOCATION,
726 vmSymbols::java_lang_NoClassDefFoundError(),
727 "Class %s, or one of its supertypes, failed class initialization",
728 external_name());
729 return false;
730 }
731 // return if already verified
732 if (is_linked()) {
733 return true;
734 }
735
736 // Timing
737 // timer handles recursion
738 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
739 JavaThread* jt = (JavaThread*)THREAD;
740
741 // link super class before linking this class
742 Klass* super_klass = super();
743 if (super_klass != NULL) {
744 if (super_klass->is_interface()) { // check if super class is an interface
745 ResourceMark rm(THREAD);
746 Exceptions::fthrow(
747 THREAD_AND_LOCATION,
748 vmSymbols::java_lang_IncompatibleClassChangeError(),
749 "class %s has interface %s as super class",
750 external_name(),
751 super_klass->external_name()
752 );
753 return false;
754 }
755
756 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
757 ik_super->link_class_impl(CHECK_false);
758 }
759
760 // link all interfaces implemented by this class before linking this class
761 Array<InstanceKlass*>* interfaces = local_interfaces();
762 int num_interfaces = interfaces->length();
763 for (int index = 0; index < num_interfaces; index++) {
764 InstanceKlass* interk = interfaces->at(index);
765 interk->link_class_impl(CHECK_false);
766 }
767
768 // in case the class is linked in the process of linking its superclasses
769 if (is_linked()) {
770 return true;
771 }
772
773 // trace only the link time for this klass that includes
774 // the verification time
775 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
776 ClassLoader::perf_class_link_selftime(),
777 ClassLoader::perf_classes_linked(),
778 jt->get_thread_stat()->perf_recursion_counts_addr(),
779 jt->get_thread_stat()->perf_timers_addr(),
780 PerfClassTraceTime::CLASS_LINK);
781
782 // verification & rewriting
783 {
784 HandleMark hm(THREAD);
785 Handle h_init_lock(THREAD, init_lock());
786 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
787 // rewritten will have been set if loader constraint error found
788 // on an earlier link attempt
789 // don't verify or rewrite if already rewritten
790 //
791
792 if (!is_linked()) {
793 if (!is_rewritten()) {
794 {
795 bool verify_ok = verify_code(THREAD);
796 if (!verify_ok) {
797 return false;
798 }
799 }
800
801 // Just in case a side-effect of verify linked this class already
802 // (which can sometimes happen since the verifier loads classes
803 // using custom class loaders, which are free to initialize things)
804 if (is_linked()) {
805 return true;
806 }
807
808 // also sets rewritten
809 rewrite_class(CHECK_false);
810 } else if (is_shared()) {
811 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
812 }
813
814 // relocate jsrs and link methods after they are all rewritten
815 link_methods(CHECK_false);
816
817 // Initialize the vtable and interface table after
818 // methods have been rewritten since rewrite may
819 // fabricate new Method*s.
820 // also does loader constraint checking
821 //
822 // initialize_vtable and initialize_itable need to be rerun for
823 // a shared class if the class is not loaded by the NULL classloader.
824 ClassLoaderData * loader_data = class_loader_data();
825 if (!(is_shared() &&
826 loader_data->is_the_null_class_loader_data())) {
827 vtable().initialize_vtable(true, CHECK_false);
828 itable().initialize_itable(true, CHECK_false);
829 }
830 #ifdef ASSERT
831 else {
832 vtable().verify(tty, true);
833 // In case itable verification is ever added.
834 // itable().verify(tty, true);
835 }
836 #endif
837 set_init_state(linked);
838 if (JvmtiExport::should_post_class_prepare()) {
839 Thread *thread = THREAD;
840 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
841 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
842 }
843 }
844 }
845 return true;
846 }
847
848 // Rewrite the byte codes of all of the methods of a class.
849 // The rewriter must be called exactly once. Rewriting must happen after
850 // verification but before the first method of the class is executed.
851 void InstanceKlass::rewrite_class(TRAPS) {
852 assert(is_loaded(), "must be loaded");
853 if (is_rewritten()) {
854 assert(is_shared(), "rewriting an unshared class?");
855 return;
856 }
857 Rewriter::rewrite(this, CHECK);
858 set_rewritten();
859 }
860
861 // Now relocate and link method entry points after class is rewritten.
862 // This is outside is_rewritten flag. In case of an exception, it can be
863 // executed more than once.
864 void InstanceKlass::link_methods(TRAPS) {
865 int len = methods()->length();
866 for (int i = len-1; i >= 0; i--) {
867 methodHandle m(THREAD, methods()->at(i));
868
869 // Set up method entry points for compiler and interpreter .
870 m->link_method(m, CHECK);
871 }
872 }
873
874 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
875 void InstanceKlass::initialize_super_interfaces(TRAPS) {
876 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
877 for (int i = 0; i < local_interfaces()->length(); ++i) {
878 InstanceKlass* ik = local_interfaces()->at(i);
879
880 // Initialization is depth first search ie. we start with top of the inheritance tree
881 // has_nonstatic_concrete_methods drives searching superinterfaces since it
882 // means has_nonstatic_concrete_methods in its superinterface hierarchy
883 if (ik->has_nonstatic_concrete_methods()) {
884 ik->initialize_super_interfaces(CHECK);
885 }
886
887 // Only initialize() interfaces that "declare" concrete methods.
888 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
889 ik->initialize(CHECK);
890 }
891 }
892 }
893
894 void InstanceKlass::initialize_impl(TRAPS) {
895 HandleMark hm(THREAD);
896
897 // Make sure klass is linked (verified) before initialization
898 // A class could already be verified, since it has been reflected upon.
899 link_class(CHECK);
900
901 DTRACE_CLASSINIT_PROBE(required, -1);
902
903 bool wait = false;
904
905 // refer to the JVM book page 47 for description of steps
906 // Step 1
907 {
908 Handle h_init_lock(THREAD, init_lock());
909 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
910
911 Thread *self = THREAD; // it's passed the current thread
912
913 // Step 2
914 // If we were to use wait() instead of waitInterruptibly() then
915 // we might end up throwing IE from link/symbol resolution sites
916 // that aren't expected to throw. This would wreak havoc. See 6320309.
917 while(is_being_initialized() && !is_reentrant_initialization(self)) {
918 wait = true;
919 ol.waitUninterruptibly(CHECK);
920 }
921
922 // Step 3
923 if (is_being_initialized() && is_reentrant_initialization(self)) {
924 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
925 return;
926 }
927
928 // Step 4
929 if (is_initialized()) {
930 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
931 return;
932 }
933
934 // Step 5
935 if (is_in_error_state()) {
936 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
937 ResourceMark rm(THREAD);
938 const char* desc = "Could not initialize class ";
939 const char* className = external_name();
940 size_t msglen = strlen(desc) + strlen(className) + 1;
941 char* message = NEW_RESOURCE_ARRAY(char, msglen);
942 if (NULL == message) {
943 // Out of memory: can't create detailed error message
944 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
945 } else {
946 jio_snprintf(message, msglen, "%s%s", desc, className);
947 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
948 }
949 }
950
951 // Step 6
952 set_init_state(being_initialized);
953 set_init_thread(self);
954 }
955
956 // Step 7
957 // Next, if C is a class rather than an interface, initialize it's super class and super
958 // interfaces.
959 if (!is_interface()) {
960 Klass* super_klass = super();
961 if (super_klass != NULL && super_klass->should_be_initialized()) {
962 super_klass->initialize(THREAD);
963 }
964 // If C implements any interface that declares a non-static, concrete method,
965 // the initialization of C triggers initialization of its super interfaces.
966 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
967 // having a superinterface that declares, non-static, concrete methods
968 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
969 initialize_super_interfaces(THREAD);
970 }
971
972 // If any exceptions, complete abruptly, throwing the same exception as above.
973 if (HAS_PENDING_EXCEPTION) {
974 Handle e(THREAD, PENDING_EXCEPTION);
975 CLEAR_PENDING_EXCEPTION;
976 {
977 EXCEPTION_MARK;
978 // Locks object, set state, and notify all waiting threads
979 set_initialization_state_and_notify(initialization_error, THREAD);
980 CLEAR_PENDING_EXCEPTION;
981 }
982 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
983 THROW_OOP(e());
984 }
985 }
986
987
988 // Look for aot compiled methods for this klass, including class initializer.
989 AOTLoader::load_for_klass(this, THREAD);
990
991 // Step 8
992 {
993 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
994 JavaThread* jt = (JavaThread*)THREAD;
995 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
996 // Timer includes any side effects of class initialization (resolution,
997 // etc), but not recursive entry into call_class_initializer().
998 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
999 ClassLoader::perf_class_init_selftime(),
1000 ClassLoader::perf_classes_inited(),
1001 jt->get_thread_stat()->perf_recursion_counts_addr(),
1002 jt->get_thread_stat()->perf_timers_addr(),
1003 PerfClassTraceTime::CLASS_CLINIT);
1004 call_class_initializer(THREAD);
1005 }
1006
1007 // Step 9
1008 if (!HAS_PENDING_EXCEPTION) {
1009 set_initialization_state_and_notify(fully_initialized, CHECK);
1010 {
1011 debug_only(vtable().verify(tty, true);)
1012 }
1013 }
1014 else {
1015 // Step 10 and 11
1016 Handle e(THREAD, PENDING_EXCEPTION);
1017 CLEAR_PENDING_EXCEPTION;
1018 // JVMTI has already reported the pending exception
1019 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1020 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1021 {
1022 EXCEPTION_MARK;
1023 set_initialization_state_and_notify(initialization_error, THREAD);
1024 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1025 // JVMTI has already reported the pending exception
1026 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1027 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1028 }
1029 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1030 if (e->is_a(SystemDictionary::Error_klass())) {
1031 THROW_OOP(e());
1032 } else {
1033 JavaCallArguments args(e);
1034 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1035 vmSymbols::throwable_void_signature(),
1036 &args);
1037 }
1038 }
1039 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1040 }
1041
1042
1043 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1044 Handle h_init_lock(THREAD, init_lock());
1045 if (h_init_lock() != NULL) {
1046 ObjectLocker ol(h_init_lock, THREAD);
1047 set_init_state(state);
1048 fence_and_clear_init_lock();
1049 ol.notify_all(CHECK);
1050 } else {
1051 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1052 set_init_state(state);
1053 }
1054 }
1055
1056 Klass* InstanceKlass::implementor() const {
1057 assert_locked_or_safepoint(Compile_lock);
1058 Klass** k = adr_implementor();
1059 if (k == NULL) {
1060 return NULL;
1061 } else {
1062 return *k;
1063 }
1064 }
1065
1066 void InstanceKlass::set_implementor(Klass* k) {
1067 assert_lock_strong(Compile_lock);
1068 assert(is_interface(), "not interface");
1069 Klass** addr = adr_implementor();
1070 assert(addr != NULL, "null addr");
1071 if (addr != NULL) {
1072 *addr = k;
1073 }
1074 }
1075
1076 int InstanceKlass::nof_implementors() const {
1077 assert_lock_strong(Compile_lock);
1078 Klass* k = implementor();
1079 if (k == NULL) {
1080 return 0;
1081 } else if (k != this) {
1082 return 1;
1083 } else {
1084 return 2;
1085 }
1086 }
1087
1088 // The embedded _implementor field can only record one implementor.
1089 // When there are more than one implementors, the _implementor field
1090 // is set to the interface Klass* itself. Following are the possible
1091 // values for the _implementor field:
1092 // NULL - no implementor
1093 // implementor Klass* - one implementor
1094 // self - more than one implementor
1095 //
1096 // The _implementor field only exists for interfaces.
1097 void InstanceKlass::add_implementor(Klass* k) {
1098 assert_lock_strong(Compile_lock);
1099 assert(is_interface(), "not interface");
1100 // Filter out my subinterfaces.
1101 // (Note: Interfaces are never on the subklass list.)
1102 if (InstanceKlass::cast(k)->is_interface()) return;
1103
1104 // Filter out subclasses whose supers already implement me.
1105 // (Note: CHA must walk subclasses of direct implementors
1106 // in order to locate indirect implementors.)
1107 Klass* sk = k->super();
1108 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1109 // We only need to check one immediate superclass, since the
1110 // implements_interface query looks at transitive_interfaces.
1111 // Any supers of the super have the same (or fewer) transitive_interfaces.
1112 return;
1113
1114 Klass* ik = implementor();
1115 if (ik == NULL) {
1116 set_implementor(k);
1117 } else if (ik != this) {
1118 // There is already an implementor. Use itself as an indicator of
1119 // more than one implementors.
1120 set_implementor(this);
1121 }
1122
1123 // The implementor also implements the transitive_interfaces
1124 for (int index = 0; index < local_interfaces()->length(); index++) {
1125 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1126 }
1127 }
1128
1129 void InstanceKlass::init_implementor() {
1130 if (is_interface()) {
1131 set_implementor(NULL);
1132 }
1133 }
1134
1135
1136 void InstanceKlass::process_interfaces(Thread *thread) {
1137 // link this class into the implementors list of every interface it implements
1138 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1139 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1140 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1141 assert(interf->is_interface(), "expected interface");
1142 interf->add_implementor(this);
1143 }
1144 }
1145
1146 bool InstanceKlass::can_be_primary_super_slow() const {
1147 if (is_interface())
1148 return false;
1149 else
1150 return Klass::can_be_primary_super_slow();
1151 }
1152
1153 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1154 Array<InstanceKlass*>* transitive_interfaces) {
1155 // The secondaries are the implemented interfaces.
1156 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1157 int num_secondaries = num_extra_slots + interfaces->length();
1158 if (num_secondaries == 0) {
1159 // Must share this for correct bootstrapping!
1160 set_secondary_supers(Universe::the_empty_klass_array());
1161 return NULL;
1162 } else if (num_extra_slots == 0) {
1163 // The secondary super list is exactly the same as the transitive interfaces, so
1164 // let's use it instead of making a copy.
1165 // Redefine classes has to be careful not to delete this!
1166 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1167 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1168 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1169 return NULL;
1170 } else {
1171 // Copy transitive interfaces to a temporary growable array to be constructed
1172 // into the secondary super list with extra slots.
1173 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1174 for (int i = 0; i < interfaces->length(); i++) {
1175 secondaries->push(interfaces->at(i));
1176 }
1177 return secondaries;
1178 }
1179 }
1180
1181 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1182 if (k->is_interface()) {
1183 return implements_interface(k);
1184 } else {
1185 return Klass::compute_is_subtype_of(k);
1186 }
1187 }
1188
1189 bool InstanceKlass::implements_interface(Klass* k) const {
1190 if (this == k) return true;
1191 assert(k->is_interface(), "should be an interface class");
1192 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1193 if (transitive_interfaces()->at(i) == k) {
1194 return true;
1195 }
1196 }
1197 return false;
1198 }
1199
1200 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1201 // Verify direct super interface
1202 if (this == k) return true;
1203 assert(k->is_interface(), "should be an interface class");
1204 for (int i = 0; i < local_interfaces()->length(); i++) {
1205 if (local_interfaces()->at(i) == k) {
1206 return true;
1207 }
1208 }
1209 return false;
1210 }
1211
1212 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1213 if (length < 0) {
1214 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1215 }
1216 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1217 report_java_out_of_memory("Requested array size exceeds VM limit");
1218 JvmtiExport::post_array_size_exhausted();
1219 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1220 }
1221 int size = objArrayOopDesc::object_size(length);
1222 Klass* ak = array_klass(n, CHECK_NULL);
1223 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1224 /* do_zero */ true, CHECK_NULL);
1225 return o;
1226 }
1227
1228 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1229 if (TraceFinalizerRegistration) {
1230 tty->print("Registered ");
1231 i->print_value_on(tty);
1232 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1233 }
1234 instanceHandle h_i(THREAD, i);
1235 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1236 JavaValue result(T_VOID);
1237 JavaCallArguments args(h_i);
1238 methodHandle mh (THREAD, Universe::finalizer_register_method());
1239 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1240 return h_i();
1241 }
1242
1243 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1244 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1245 int size = size_helper(); // Query before forming handle.
1246
1247 instanceOop i;
1248
1249 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1250 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1251 i = register_finalizer(i, CHECK_NULL);
1252 }
1253 return i;
1254 }
1255
1256 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1257 return instanceHandle(THREAD, allocate_instance(THREAD));
1258 }
1259
1260 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1261 if (is_interface() || is_abstract()) {
1262 ResourceMark rm(THREAD);
1263 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1264 : vmSymbols::java_lang_InstantiationException(), external_name());
1265 }
1266 if (this == SystemDictionary::Class_klass()) {
1267 ResourceMark rm(THREAD);
1268 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1269 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1270 }
1271 }
1272
1273 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1274 // Need load-acquire for lock-free read
1275 if (array_klasses_acquire() == NULL) {
1276 if (or_null) return NULL;
1277
1278 ResourceMark rm;
1279 JavaThread *jt = (JavaThread *)THREAD;
1280 {
1281 // Atomic creation of array_klasses
1282 MutexLocker mc(Compile_lock, THREAD); // for vtables
1283 MutexLocker ma(MultiArray_lock, THREAD);
1284
1285 // Check if update has already taken place
1286 if (array_klasses() == NULL) {
1287 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1288 // use 'release' to pair with lock-free load
1289 release_set_array_klasses(k);
1290 }
1291 }
1292 }
1293 // _this will always be set at this point
1294 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1295 if (or_null) {
1296 return oak->array_klass_or_null(n);
1297 }
1298 return oak->array_klass(n, THREAD);
1299 }
1300
1301 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1302 return array_klass_impl(or_null, 1, THREAD);
1303 }
1304
1305 static int call_class_initializer_counter = 0; // for debugging
1306
1307 Method* InstanceKlass::class_initializer() const {
1308 Method* clinit = find_method(
1309 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1310 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1311 return clinit;
1312 }
1313 return NULL;
1314 }
1315
1316 void InstanceKlass::call_class_initializer(TRAPS) {
1317 if (ReplayCompiles &&
1318 (ReplaySuppressInitializers == 1 ||
1319 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1320 // Hide the existence of the initializer for the purpose of replaying the compile
1321 return;
1322 }
1323
1324 methodHandle h_method(THREAD, class_initializer());
1325 assert(!is_initialized(), "we cannot initialize twice");
1326 LogTarget(Info, class, init) lt;
1327 if (lt.is_enabled()) {
1328 ResourceMark rm;
1329 LogStream ls(lt);
1330 ls.print("%d Initializing ", call_class_initializer_counter++);
1331 name()->print_value_on(&ls);
1332 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1333 }
1334 if (h_method() != NULL) {
1335 JavaCallArguments args; // No arguments
1336 JavaValue result(T_VOID);
1337 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1338 }
1339 }
1340
1341
1342 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1343 InterpreterOopMap* entry_for) {
1344 // Lazily create the _oop_map_cache at first request
1345 // Lock-free access requires load_acquire.
1346 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1347 if (oop_map_cache == NULL) {
1348 MutexLocker x(OopMapCacheAlloc_lock);
1349 // Check if _oop_map_cache was allocated while we were waiting for this lock
1350 if ((oop_map_cache = _oop_map_cache) == NULL) {
1351 oop_map_cache = new OopMapCache();
1352 // Ensure _oop_map_cache is stable, since it is examined without a lock
1353 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1354 }
1355 }
1356 // _oop_map_cache is constant after init; lookup below does its own locking.
1357 oop_map_cache->lookup(method, bci, entry_for);
1358 }
1359
1360
1361 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1362 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1363 Symbol* f_name = fs.name();
1364 Symbol* f_sig = fs.signature();
1365 if (f_name == name && f_sig == sig) {
1366 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1367 return true;
1368 }
1369 }
1370 return false;
1371 }
1372
1373
1374 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1375 const int n = local_interfaces()->length();
1376 for (int i = 0; i < n; i++) {
1377 Klass* intf1 = local_interfaces()->at(i);
1378 assert(intf1->is_interface(), "just checking type");
1379 // search for field in current interface
1380 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1381 assert(fd->is_static(), "interface field must be static");
1382 return intf1;
1383 }
1384 // search for field in direct superinterfaces
1385 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1386 if (intf2 != NULL) return intf2;
1387 }
1388 // otherwise field lookup fails
1389 return NULL;
1390 }
1391
1392
1393 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1394 // search order according to newest JVM spec (5.4.3.2, p.167).
1395 // 1) search for field in current klass
1396 if (find_local_field(name, sig, fd)) {
1397 return const_cast<InstanceKlass*>(this);
1398 }
1399 // 2) search for field recursively in direct superinterfaces
1400 { Klass* intf = find_interface_field(name, sig, fd);
1401 if (intf != NULL) return intf;
1402 }
1403 // 3) apply field lookup recursively if superclass exists
1404 { Klass* supr = super();
1405 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1406 }
1407 // 4) otherwise field lookup fails
1408 return NULL;
1409 }
1410
1411
1412 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1413 // search order according to newest JVM spec (5.4.3.2, p.167).
1414 // 1) search for field in current klass
1415 if (find_local_field(name, sig, fd)) {
1416 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1417 }
1418 // 2) search for field recursively in direct superinterfaces
1419 if (is_static) {
1420 Klass* intf = find_interface_field(name, sig, fd);
1421 if (intf != NULL) return intf;
1422 }
1423 // 3) apply field lookup recursively if superclass exists
1424 { Klass* supr = super();
1425 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1426 }
1427 // 4) otherwise field lookup fails
1428 return NULL;
1429 }
1430
1431
1432 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1433 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1434 if (fs.offset() == offset) {
1435 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1436 if (fd->is_static() == is_static) return true;
1437 }
1438 }
1439 return false;
1440 }
1441
1442
1443 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1444 Klass* klass = const_cast<InstanceKlass*>(this);
1445 while (klass != NULL) {
1446 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1447 return true;
1448 }
1449 klass = klass->super();
1450 }
1451 return false;
1452 }
1453
1454
1455 void InstanceKlass::methods_do(void f(Method* method)) {
1456 // Methods aren't stable until they are loaded. This can be read outside
1457 // a lock through the ClassLoaderData for profiling
1458 if (!is_loaded()) {
1459 return;
1460 }
1461
1462 int len = methods()->length();
1463 for (int index = 0; index < len; index++) {
1464 Method* m = methods()->at(index);
1465 assert(m->is_method(), "must be method");
1466 f(m);
1467 }
1468 }
1469
1470
1471 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1472 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1473 if (fs.access_flags().is_static()) {
1474 fieldDescriptor& fd = fs.field_descriptor();
1475 cl->do_field(&fd);
1476 }
1477 }
1478 }
1479
1480
1481 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1482 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1483 if (fs.access_flags().is_static()) {
1484 fieldDescriptor& fd = fs.field_descriptor();
1485 f(&fd, mirror, CHECK);
1486 }
1487 }
1488 }
1489
1490
1491 static int compare_fields_by_offset(int* a, int* b) {
1492 return a[0] - b[0];
1493 }
1494
1495 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1496 InstanceKlass* super = superklass();
1497 if (super != NULL) {
1498 super->do_nonstatic_fields(cl);
1499 }
1500 fieldDescriptor fd;
1501 int length = java_fields_count();
1502 // In DebugInfo nonstatic fields are sorted by offset.
1503 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1504 int j = 0;
1505 for (int i = 0; i < length; i += 1) {
1506 fd.reinitialize(this, i);
1507 if (!fd.is_static()) {
1508 fields_sorted[j + 0] = fd.offset();
1509 fields_sorted[j + 1] = i;
1510 j += 2;
1511 }
1512 }
1513 if (j > 0) {
1514 length = j;
1515 // _sort_Fn is defined in growableArray.hpp.
1516 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1517 for (int i = 0; i < length; i += 2) {
1518 fd.reinitialize(this, fields_sorted[i + 1]);
1519 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1520 cl->do_field(&fd);
1521 }
1522 }
1523 FREE_C_HEAP_ARRAY(int, fields_sorted);
1524 }
1525
1526
1527 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1528 if (array_klasses() != NULL)
1529 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1530 }
1531
1532 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1533 if (array_klasses() != NULL)
1534 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1535 }
1536
1537 #ifdef ASSERT
1538 static int linear_search(const Array<Method*>* methods,
1539 const Symbol* name,
1540 const Symbol* signature) {
1541 const int len = methods->length();
1542 for (int index = 0; index < len; index++) {
1543 const Method* const m = methods->at(index);
1544 assert(m->is_method(), "must be method");
1545 if (m->signature() == signature && m->name() == name) {
1546 return index;
1547 }
1548 }
1549 return -1;
1550 }
1551 #endif
1552
1553 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1554 int len = methods->length();
1555 // methods are sorted, so do binary search
1556 int l = 0;
1557 int h = len - 1;
1558 while (l <= h) {
1559 int mid = (l + h) >> 1;
1560 Method* m = methods->at(mid);
1561 assert(m->is_method(), "must be method");
1562 int res = m->name()->fast_compare(name);
1563 if (res == 0) {
1564 return mid;
1565 } else if (res < 0) {
1566 l = mid + 1;
1567 } else {
1568 h = mid - 1;
1569 }
1570 }
1571 return -1;
1572 }
1573
1574 // find_method looks up the name/signature in the local methods array
1575 Method* InstanceKlass::find_method(const Symbol* name,
1576 const Symbol* signature) const {
1577 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1578 }
1579
1580 Method* InstanceKlass::find_method_impl(const Symbol* name,
1581 const Symbol* signature,
1582 OverpassLookupMode overpass_mode,
1583 StaticLookupMode static_mode,
1584 PrivateLookupMode private_mode) const {
1585 return InstanceKlass::find_method_impl(methods(),
1586 name,
1587 signature,
1588 overpass_mode,
1589 static_mode,
1590 private_mode);
1591 }
1592
1593 // find_instance_method looks up the name/signature in the local methods array
1594 // and skips over static methods
1595 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1596 const Symbol* name,
1597 const Symbol* signature,
1598 PrivateLookupMode private_mode) {
1599 Method* const meth = InstanceKlass::find_method_impl(methods,
1600 name,
1601 signature,
1602 find_overpass,
1603 skip_static,
1604 private_mode);
1605 assert(((meth == NULL) || !meth->is_static()),
1606 "find_instance_method should have skipped statics");
1607 return meth;
1608 }
1609
1610 // find_instance_method looks up the name/signature in the local methods array
1611 // and skips over static methods
1612 Method* InstanceKlass::find_instance_method(const Symbol* name,
1613 const Symbol* signature,
1614 PrivateLookupMode private_mode) const {
1615 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1616 }
1617
1618 // Find looks up the name/signature in the local methods array
1619 // and filters on the overpass, static and private flags
1620 // This returns the first one found
1621 // note that the local methods array can have up to one overpass, one static
1622 // and one instance (private or not) with the same name/signature
1623 Method* InstanceKlass::find_local_method(const Symbol* name,
1624 const Symbol* signature,
1625 OverpassLookupMode overpass_mode,
1626 StaticLookupMode static_mode,
1627 PrivateLookupMode private_mode) const {
1628 return InstanceKlass::find_method_impl(methods(),
1629 name,
1630 signature,
1631 overpass_mode,
1632 static_mode,
1633 private_mode);
1634 }
1635
1636 // Find looks up the name/signature in the local methods array
1637 // and filters on the overpass, static and private flags
1638 // This returns the first one found
1639 // note that the local methods array can have up to one overpass, one static
1640 // and one instance (private or not) with the same name/signature
1641 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1642 const Symbol* name,
1643 const Symbol* signature,
1644 OverpassLookupMode overpass_mode,
1645 StaticLookupMode static_mode,
1646 PrivateLookupMode private_mode) {
1647 return InstanceKlass::find_method_impl(methods,
1648 name,
1649 signature,
1650 overpass_mode,
1651 static_mode,
1652 private_mode);
1653 }
1654
1655 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1656 const Symbol* name,
1657 const Symbol* signature) {
1658 return InstanceKlass::find_method_impl(methods,
1659 name,
1660 signature,
1661 find_overpass,
1662 find_static,
1663 find_private);
1664 }
1665
1666 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1667 const Symbol* name,
1668 const Symbol* signature,
1669 OverpassLookupMode overpass_mode,
1670 StaticLookupMode static_mode,
1671 PrivateLookupMode private_mode) {
1672 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1673 return hit >= 0 ? methods->at(hit): NULL;
1674 }
1675
1676 // true if method matches signature and conforms to skipping_X conditions.
1677 static bool method_matches(const Method* m,
1678 const Symbol* signature,
1679 bool skipping_overpass,
1680 bool skipping_static,
1681 bool skipping_private) {
1682 return ((m->signature() == signature) &&
1683 (!skipping_overpass || !m->is_overpass()) &&
1684 (!skipping_static || !m->is_static()) &&
1685 (!skipping_private || !m->is_private()));
1686 }
1687
1688 // Used directly for default_methods to find the index into the
1689 // default_vtable_indices, and indirectly by find_method
1690 // find_method_index looks in the local methods array to return the index
1691 // of the matching name/signature. If, overpass methods are being ignored,
1692 // the search continues to find a potential non-overpass match. This capability
1693 // is important during method resolution to prefer a static method, for example,
1694 // over an overpass method.
1695 // There is the possibility in any _method's array to have the same name/signature
1696 // for a static method, an overpass method and a local instance method
1697 // To correctly catch a given method, the search criteria may need
1698 // to explicitly skip the other two. For local instance methods, it
1699 // is often necessary to skip private methods
1700 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1701 const Symbol* name,
1702 const Symbol* signature,
1703 OverpassLookupMode overpass_mode,
1704 StaticLookupMode static_mode,
1705 PrivateLookupMode private_mode) {
1706 const bool skipping_overpass = (overpass_mode == skip_overpass);
1707 const bool skipping_static = (static_mode == skip_static);
1708 const bool skipping_private = (private_mode == skip_private);
1709 const int hit = binary_search(methods, name);
1710 if (hit != -1) {
1711 const Method* const m = methods->at(hit);
1712
1713 // Do linear search to find matching signature. First, quick check
1714 // for common case, ignoring overpasses if requested.
1715 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1716 return hit;
1717 }
1718
1719 // search downwards through overloaded methods
1720 int i;
1721 for (i = hit - 1; i >= 0; --i) {
1722 const Method* const m = methods->at(i);
1723 assert(m->is_method(), "must be method");
1724 if (m->name() != name) {
1725 break;
1726 }
1727 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1728 return i;
1729 }
1730 }
1731 // search upwards
1732 for (i = hit + 1; i < methods->length(); ++i) {
1733 const Method* const m = methods->at(i);
1734 assert(m->is_method(), "must be method");
1735 if (m->name() != name) {
1736 break;
1737 }
1738 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1739 return i;
1740 }
1741 }
1742 // not found
1743 #ifdef ASSERT
1744 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1745 linear_search(methods, name, signature);
1746 assert(-1 == index, "binary search should have found entry %d", index);
1747 #endif
1748 }
1749 return -1;
1750 }
1751
1752 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1753 return find_method_by_name(methods(), name, end);
1754 }
1755
1756 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1757 const Symbol* name,
1758 int* end_ptr) {
1759 assert(end_ptr != NULL, "just checking");
1760 int start = binary_search(methods, name);
1761 int end = start + 1;
1762 if (start != -1) {
1763 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1764 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1765 *end_ptr = end;
1766 return start;
1767 }
1768 return -1;
1769 }
1770
1771 // uncached_lookup_method searches both the local class methods array and all
1772 // superclasses methods arrays, skipping any overpass methods in superclasses,
1773 // and possibly skipping private methods.
1774 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1775 const Symbol* signature,
1776 OverpassLookupMode overpass_mode,
1777 PrivateLookupMode private_mode) const {
1778 OverpassLookupMode overpass_local_mode = overpass_mode;
1779 const Klass* klass = this;
1780 while (klass != NULL) {
1781 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1782 signature,
1783 overpass_local_mode,
1784 find_static,
1785 private_mode);
1786 if (method != NULL) {
1787 return method;
1788 }
1789 klass = klass->super();
1790 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1791 }
1792 return NULL;
1793 }
1794
1795 #ifdef ASSERT
1796 // search through class hierarchy and return true if this class or
1797 // one of the superclasses was redefined
1798 bool InstanceKlass::has_redefined_this_or_super() const {
1799 const Klass* klass = this;
1800 while (klass != NULL) {
1801 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1802 return true;
1803 }
1804 klass = klass->super();
1805 }
1806 return false;
1807 }
1808 #endif
1809
1810 // lookup a method in the default methods list then in all transitive interfaces
1811 // Do NOT return private or static methods
1812 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1813 Symbol* signature) const {
1814 Method* m = NULL;
1815 if (default_methods() != NULL) {
1816 m = find_method(default_methods(), name, signature);
1817 }
1818 // Look up interfaces
1819 if (m == NULL) {
1820 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1821 }
1822 return m;
1823 }
1824
1825 // lookup a method in all the interfaces that this class implements
1826 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1827 // They should only be found in the initial InterfaceMethodRef
1828 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1829 Symbol* signature,
1830 DefaultsLookupMode defaults_mode) const {
1831 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1832 int num_ifs = all_ifs->length();
1833 InstanceKlass *ik = NULL;
1834 for (int i = 0; i < num_ifs; i++) {
1835 ik = all_ifs->at(i);
1836 Method* m = ik->lookup_method(name, signature);
1837 if (m != NULL && m->is_public() && !m->is_static() &&
1838 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1839 return m;
1840 }
1841 }
1842 return NULL;
1843 }
1844
1845 /* jni_id_for_impl for jfieldIds only */
1846 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1847 MutexLocker ml(JfieldIdCreation_lock);
1848 // Retry lookup after we got the lock
1849 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1850 if (probe == NULL) {
1851 // Slow case, allocate new static field identifier
1852 probe = new JNIid(this, offset, jni_ids());
1853 set_jni_ids(probe);
1854 }
1855 return probe;
1856 }
1857
1858
1859 /* jni_id_for for jfieldIds only */
1860 JNIid* InstanceKlass::jni_id_for(int offset) {
1861 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1862 if (probe == NULL) {
1863 probe = jni_id_for_impl(offset);
1864 }
1865 return probe;
1866 }
1867
1868 u2 InstanceKlass::enclosing_method_data(int offset) const {
1869 const Array<jushort>* const inner_class_list = inner_classes();
1870 if (inner_class_list == NULL) {
1871 return 0;
1872 }
1873 const int length = inner_class_list->length();
1874 if (length % inner_class_next_offset == 0) {
1875 return 0;
1876 }
1877 const int index = length - enclosing_method_attribute_size;
1878 assert(offset < enclosing_method_attribute_size, "invalid offset");
1879 return inner_class_list->at(index + offset);
1880 }
1881
1882 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1883 u2 method_index) {
1884 Array<jushort>* inner_class_list = inner_classes();
1885 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1886 int length = inner_class_list->length();
1887 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1888 int index = length - enclosing_method_attribute_size;
1889 inner_class_list->at_put(
1890 index + enclosing_method_class_index_offset, class_index);
1891 inner_class_list->at_put(
1892 index + enclosing_method_method_index_offset, method_index);
1893 }
1894 }
1895
1896 // Lookup or create a jmethodID.
1897 // This code is called by the VMThread and JavaThreads so the
1898 // locking has to be done very carefully to avoid deadlocks
1899 // and/or other cache consistency problems.
1900 //
1901 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1902 size_t idnum = (size_t)method_h->method_idnum();
1903 jmethodID* jmeths = methods_jmethod_ids_acquire();
1904 size_t length = 0;
1905 jmethodID id = NULL;
1906
1907 // We use a double-check locking idiom here because this cache is
1908 // performance sensitive. In the normal system, this cache only
1909 // transitions from NULL to non-NULL which is safe because we use
1910 // release_set_methods_jmethod_ids() to advertise the new cache.
1911 // A partially constructed cache should never be seen by a racing
1912 // thread. We also use release_store() to save a new jmethodID
1913 // in the cache so a partially constructed jmethodID should never be
1914 // seen either. Cache reads of existing jmethodIDs proceed without a
1915 // lock, but cache writes of a new jmethodID requires uniqueness and
1916 // creation of the cache itself requires no leaks so a lock is
1917 // generally acquired in those two cases.
1918 //
1919 // If the RedefineClasses() API has been used, then this cache can
1920 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1921 // Cache creation requires no leaks and we require safety between all
1922 // cache accesses and freeing of the old cache so a lock is generally
1923 // acquired when the RedefineClasses() API has been used.
1924
1925 if (jmeths != NULL) {
1926 // the cache already exists
1927 if (!idnum_can_increment()) {
1928 // the cache can't grow so we can just get the current values
1929 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1930 } else {
1931 // cache can grow so we have to be more careful
1932 if (Threads::number_of_threads() == 0 ||
1933 SafepointSynchronize::is_at_safepoint()) {
1934 // we're single threaded or at a safepoint - no locking needed
1935 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1936 } else {
1937 MutexLocker ml(JmethodIdCreation_lock);
1938 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1939 }
1940 }
1941 }
1942 // implied else:
1943 // we need to allocate a cache so default length and id values are good
1944
1945 if (jmeths == NULL || // no cache yet
1946 length <= idnum || // cache is too short
1947 id == NULL) { // cache doesn't contain entry
1948
1949 // This function can be called by the VMThread so we have to do all
1950 // things that might block on a safepoint before grabbing the lock.
1951 // Otherwise, we can deadlock with the VMThread or have a cache
1952 // consistency issue. These vars keep track of what we might have
1953 // to free after the lock is dropped.
1954 jmethodID to_dealloc_id = NULL;
1955 jmethodID* to_dealloc_jmeths = NULL;
1956
1957 // may not allocate new_jmeths or use it if we allocate it
1958 jmethodID* new_jmeths = NULL;
1959 if (length <= idnum) {
1960 // allocate a new cache that might be used
1961 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1962 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1963 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1964 // cache size is stored in element[0], other elements offset by one
1965 new_jmeths[0] = (jmethodID)size;
1966 }
1967
1968 // allocate a new jmethodID that might be used
1969 jmethodID new_id = NULL;
1970 if (method_h->is_old() && !method_h->is_obsolete()) {
1971 // The method passed in is old (but not obsolete), we need to use the current version
1972 Method* current_method = method_with_idnum((int)idnum);
1973 assert(current_method != NULL, "old and but not obsolete, so should exist");
1974 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1975 } else {
1976 // It is the current version of the method or an obsolete method,
1977 // use the version passed in
1978 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1979 }
1980
1981 if (Threads::number_of_threads() == 0 ||
1982 SafepointSynchronize::is_at_safepoint()) {
1983 // we're single threaded or at a safepoint - no locking needed
1984 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1985 &to_dealloc_id, &to_dealloc_jmeths);
1986 } else {
1987 MutexLocker ml(JmethodIdCreation_lock);
1988 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1989 &to_dealloc_id, &to_dealloc_jmeths);
1990 }
1991
1992 // The lock has been dropped so we can free resources.
1993 // Free up either the old cache or the new cache if we allocated one.
1994 if (to_dealloc_jmeths != NULL) {
1995 FreeHeap(to_dealloc_jmeths);
1996 }
1997 // free up the new ID since it wasn't needed
1998 if (to_dealloc_id != NULL) {
1999 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2000 }
2001 }
2002 return id;
2003 }
2004
2005 // Figure out how many jmethodIDs haven't been allocated, and make
2006 // sure space for them is pre-allocated. This makes getting all
2007 // method ids much, much faster with classes with more than 8
2008 // methods, and has a *substantial* effect on performance with jvmti
2009 // code that loads all jmethodIDs for all classes.
2010 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2011 int new_jmeths = 0;
2012 int length = methods()->length();
2013 for (int index = start_offset; index < length; index++) {
2014 Method* m = methods()->at(index);
2015 jmethodID id = m->find_jmethod_id_or_null();
2016 if (id == NULL) {
2017 new_jmeths++;
2018 }
2019 }
2020 if (new_jmeths != 0) {
2021 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2022 }
2023 }
2024
2025 // Common code to fetch the jmethodID from the cache or update the
2026 // cache with the new jmethodID. This function should never do anything
2027 // that causes the caller to go to a safepoint or we can deadlock with
2028 // the VMThread or have cache consistency issues.
2029 //
2030 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2031 size_t idnum, jmethodID new_id,
2032 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2033 jmethodID** to_dealloc_jmeths_p) {
2034 assert(new_id != NULL, "sanity check");
2035 assert(to_dealloc_id_p != NULL, "sanity check");
2036 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2037 assert(Threads::number_of_threads() == 0 ||
2038 SafepointSynchronize::is_at_safepoint() ||
2039 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2040
2041 // reacquire the cache - we are locked, single threaded or at a safepoint
2042 jmethodID* jmeths = methods_jmethod_ids_acquire();
2043 jmethodID id = NULL;
2044 size_t length = 0;
2045
2046 if (jmeths == NULL || // no cache yet
2047 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2048 if (jmeths != NULL) {
2049 // copy any existing entries from the old cache
2050 for (size_t index = 0; index < length; index++) {
2051 new_jmeths[index+1] = jmeths[index+1];
2052 }
2053 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2054 }
2055 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2056 } else {
2057 // fetch jmethodID (if any) from the existing cache
2058 id = jmeths[idnum+1];
2059 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2060 }
2061 if (id == NULL) {
2062 // No matching jmethodID in the existing cache or we have a new
2063 // cache or we just grew the cache. This cache write is done here
2064 // by the first thread to win the foot race because a jmethodID
2065 // needs to be unique once it is generally available.
2066 id = new_id;
2067
2068 // The jmethodID cache can be read while unlocked so we have to
2069 // make sure the new jmethodID is complete before installing it
2070 // in the cache.
2071 OrderAccess::release_store(&jmeths[idnum+1], id);
2072 } else {
2073 *to_dealloc_id_p = new_id; // save new id for later delete
2074 }
2075 return id;
2076 }
2077
2078
2079 // Common code to get the jmethodID cache length and the jmethodID
2080 // value at index idnum if there is one.
2081 //
2082 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2083 size_t idnum, size_t *length_p, jmethodID* id_p) {
2084 assert(cache != NULL, "sanity check");
2085 assert(length_p != NULL, "sanity check");
2086 assert(id_p != NULL, "sanity check");
2087
2088 // cache size is stored in element[0], other elements offset by one
2089 *length_p = (size_t)cache[0];
2090 if (*length_p <= idnum) { // cache is too short
2091 *id_p = NULL;
2092 } else {
2093 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2094 }
2095 }
2096
2097
2098 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2099 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2100 size_t idnum = (size_t)method->method_idnum();
2101 jmethodID* jmeths = methods_jmethod_ids_acquire();
2102 size_t length; // length assigned as debugging crumb
2103 jmethodID id = NULL;
2104 if (jmeths != NULL && // If there is a cache
2105 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2106 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2107 }
2108 return id;
2109 }
2110
2111 inline DependencyContext InstanceKlass::dependencies() {
2112 DependencyContext dep_context(&_dep_context);
2113 return dep_context;
2114 }
2115
2116 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2117 return dependencies().mark_dependent_nmethods(changes);
2118 }
2119
2120 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2121 dependencies().add_dependent_nmethod(nm);
2122 }
2123
2124 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2125 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2126 }
2127
2128 #ifndef PRODUCT
2129 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2130 dependencies().print_dependent_nmethods(verbose);
2131 }
2132
2133 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2134 return dependencies().is_dependent_nmethod(nm);
2135 }
2136 #endif //PRODUCT
2137
2138 void InstanceKlass::clean_weak_instanceklass_links() {
2139 clean_implementors_list();
2140 clean_method_data();
2141
2142 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2143 DependencyContext dep_context(&_dep_context);
2144 dep_context.expunge_stale_entries();
2145 }
2146
2147 void InstanceKlass::clean_implementors_list() {
2148 assert(is_loader_alive(), "this klass should be live");
2149 if (is_interface()) {
2150 if (ClassUnloading) {
2151 Klass* impl = implementor();
2152 if (impl != NULL) {
2153 if (!impl->is_loader_alive()) {
2154 // remove this guy
2155 Klass** klass = adr_implementor();
2156 assert(klass != NULL, "null klass");
2157 if (klass != NULL) {
2158 *klass = NULL;
2159 }
2160 }
2161 }
2162 }
2163 }
2164 }
2165
2166 void InstanceKlass::clean_method_data() {
2167 for (int m = 0; m < methods()->length(); m++) {
2168 MethodData* mdo = methods()->at(m)->method_data();
2169 if (mdo != NULL) {
2170 mdo->clean_method_data(/*always_clean*/false);
2171 }
2172 }
2173 }
2174
2175 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2176 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2177 ResourceMark rm;
2178 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2179 return false;
2180 }
2181
2182 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2183 if (local_interfaces != NULL) {
2184 int length = local_interfaces->length();
2185 for (int i = 0; i < length; i++) {
2186 InstanceKlass* intf = local_interfaces->at(i);
2187 if (!intf->has_passed_fingerprint_check()) {
2188 ResourceMark rm;
2189 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2190 return false;
2191 }
2192 }
2193 }
2194
2195 return true;
2196 }
2197
2198 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2199 #if INCLUDE_AOT
2200 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2201 if (CalculateClassFingerprint) {
2202 // (1) We are running AOT to generate a shared library.
2203 return true;
2204 }
2205 if (DumpSharedSpaces) {
2206 // (2) We are running -Xshare:dump to create a shared archive
2207 return true;
2208 }
2209 if (UseAOT && is_unsafe_anonymous) {
2210 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2211 return true;
2212 }
2213 #endif
2214
2215 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2216 // but do not store the 64-bit fingerprint to save space.
2217 return false;
2218 }
2219
2220 bool InstanceKlass::has_stored_fingerprint() const {
2221 #if INCLUDE_AOT
2222 return should_store_fingerprint() || is_shared();
2223 #else
2224 return false;
2225 #endif
2226 }
2227
2228 uint64_t InstanceKlass::get_stored_fingerprint() const {
2229 address adr = adr_fingerprint();
2230 if (adr != NULL) {
2231 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2232 }
2233 return 0;
2234 }
2235
2236 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2237 address adr = adr_fingerprint();
2238 if (adr != NULL) {
2239 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2240
2241 ResourceMark rm;
2242 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2243 }
2244 }
2245
2246 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2247 Klass::metaspace_pointers_do(it);
2248
2249 if (log_is_enabled(Trace, cds)) {
2250 ResourceMark rm;
2251 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2252 }
2253
2254 it->push(&_annotations);
2255 it->push((Klass**)&_array_klasses);
2256 it->push(&_constants);
2257 it->push(&_inner_classes);
2258 it->push(&_array_name);
2259 #if INCLUDE_JVMTI
2260 it->push(&_previous_versions);
2261 #endif
2262 it->push(&_methods);
2263 it->push(&_default_methods);
2264 it->push(&_local_interfaces);
2265 it->push(&_transitive_interfaces);
2266 it->push(&_method_ordering);
2267 it->push(&_default_vtable_indices);
2268 it->push(&_fields);
2269
2270 if (itable_length() > 0) {
2271 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2272 int method_table_offset_in_words = ioe->offset()/wordSize;
2273 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2274 / itableOffsetEntry::size();
2275
2276 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2277 if (ioe->interface_klass() != NULL) {
2278 it->push(ioe->interface_klass_addr());
2279 itableMethodEntry* ime = ioe->first_method_entry(this);
2280 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2281 for (int index = 0; index < n; index ++) {
2282 it->push(ime[index].method_addr());
2283 }
2284 }
2285 }
2286 }
2287
2288 it->push(&_nest_members);
2289 }
2290
2291 void InstanceKlass::remove_unshareable_info() {
2292 Klass::remove_unshareable_info();
2293
2294 if (is_in_error_state()) {
2295 // Classes are attempted to link during dumping and may fail,
2296 // but these classes are still in the dictionary and class list in CLD.
2297 // Check in_error state first because in_error is > linked state, so
2298 // is_linked() is true.
2299 // If there's a linking error, there is nothing else to remove.
2300 return;
2301 }
2302
2303 // Unlink the class
2304 if (is_linked()) {
2305 unlink_class();
2306 }
2307 {
2308 MutexLocker ml(Compile_lock);
2309 init_implementor();
2310 }
2311
2312 constants()->remove_unshareable_info();
2313
2314 for (int i = 0; i < methods()->length(); i++) {
2315 Method* m = methods()->at(i);
2316 m->remove_unshareable_info();
2317 }
2318
2319 // do array classes also.
2320 if (array_klasses() != NULL) {
2321 array_klasses()->remove_unshareable_info();
2322 }
2323
2324 // These are not allocated from metaspace, but they should should all be empty
2325 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2326 guarantee(_source_debug_extension == NULL, "must be");
2327 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2328 guarantee(_osr_nmethods_head == NULL, "must be");
2329
2330 #if INCLUDE_JVMTI
2331 guarantee(_breakpoints == NULL, "must be");
2332 guarantee(_previous_versions == NULL, "must be");
2333 #endif
2334
2335 _init_thread = NULL;
2336 _methods_jmethod_ids = NULL;
2337 _jni_ids = NULL;
2338 _oop_map_cache = NULL;
2339 // clear _nest_host to ensure re-load at runtime
2340 _nest_host = NULL;
2341 }
2342
2343 void InstanceKlass::remove_java_mirror() {
2344 Klass::remove_java_mirror();
2345
2346 // do array classes also.
2347 if (array_klasses() != NULL) {
2348 array_klasses()->remove_java_mirror();
2349 }
2350 }
2351
2352 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2353 set_package(loader_data, CHECK);
2354 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2355
2356 Array<Method*>* methods = this->methods();
2357 int num_methods = methods->length();
2358 for (int index2 = 0; index2 < num_methods; ++index2) {
2359 methodHandle m(THREAD, methods->at(index2));
2360 m->restore_unshareable_info(CHECK);
2361 }
2362 if (JvmtiExport::has_redefined_a_class()) {
2363 // Reinitialize vtable because RedefineClasses may have changed some
2364 // entries in this vtable for super classes so the CDS vtable might
2365 // point to old or obsolete entries. RedefineClasses doesn't fix up
2366 // vtables in the shared system dictionary, only the main one.
2367 // It also redefines the itable too so fix that too.
2368 vtable().initialize_vtable(false, CHECK);
2369 itable().initialize_itable(false, CHECK);
2370 }
2371
2372 // restore constant pool resolved references
2373 constants()->restore_unshareable_info(CHECK);
2374
2375 if (array_klasses() != NULL) {
2376 // Array classes have null protection domain.
2377 // --> see ArrayKlass::complete_create_array_klass()
2378 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2379 }
2380 }
2381
2382 // returns true IFF is_in_error_state() has been changed as a result of this call.
2383 bool InstanceKlass::check_sharing_error_state() {
2384 assert(DumpSharedSpaces, "should only be called during dumping");
2385 bool old_state = is_in_error_state();
2386
2387 if (!is_in_error_state()) {
2388 bool bad = false;
2389 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2390 if (sup->is_in_error_state()) {
2391 bad = true;
2392 break;
2393 }
2394 }
2395 if (!bad) {
2396 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2397 for (int i = 0; i < interfaces->length(); i++) {
2398 InstanceKlass* iface = interfaces->at(i);
2399 if (iface->is_in_error_state()) {
2400 bad = true;
2401 break;
2402 }
2403 }
2404 }
2405
2406 if (bad) {
2407 set_in_error_state();
2408 }
2409 }
2410
2411 return (old_state != is_in_error_state());
2412 }
2413
2414 #if INCLUDE_JVMTI
2415 static void clear_all_breakpoints(Method* m) {
2416 m->clear_all_breakpoints();
2417 }
2418 #endif
2419
2420 void InstanceKlass::unload_class(InstanceKlass* ik) {
2421 // Release dependencies.
2422 ik->dependencies().remove_all_dependents();
2423
2424 // notify the debugger
2425 if (JvmtiExport::should_post_class_unload()) {
2426 JvmtiExport::post_class_unload(ik);
2427 }
2428
2429 // notify ClassLoadingService of class unload
2430 ClassLoadingService::notify_class_unloaded(ik);
2431
2432 #if INCLUDE_JFR
2433 assert(ik != NULL, "invariant");
2434 EventClassUnload event;
2435 event.set_unloadedClass(ik);
2436 event.set_definingClassLoader(ik->class_loader_data());
2437 event.commit();
2438 #endif
2439 }
2440
2441 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2442 // Clean up C heap
2443 ik->release_C_heap_structures();
2444 ik->constants()->release_C_heap_structures();
2445 }
2446
2447 void InstanceKlass::release_C_heap_structures() {
2448 // Can't release the constant pool here because the constant pool can be
2449 // deallocated separately from the InstanceKlass for default methods and
2450 // redefine classes.
2451
2452 // Deallocate oop map cache
2453 if (_oop_map_cache != NULL) {
2454 delete _oop_map_cache;
2455 _oop_map_cache = NULL;
2456 }
2457
2458 // Deallocate JNI identifiers for jfieldIDs
2459 JNIid::deallocate(jni_ids());
2460 set_jni_ids(NULL);
2461
2462 jmethodID* jmeths = methods_jmethod_ids_acquire();
2463 if (jmeths != (jmethodID*)NULL) {
2464 release_set_methods_jmethod_ids(NULL);
2465 FreeHeap(jmeths);
2466 }
2467
2468 assert(_dep_context == DependencyContext::EMPTY,
2469 "dependencies should already be cleaned");
2470
2471 #if INCLUDE_JVMTI
2472 // Deallocate breakpoint records
2473 if (breakpoints() != 0x0) {
2474 methods_do(clear_all_breakpoints);
2475 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2476 }
2477
2478 // deallocate the cached class file
2479 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2480 os::free(_cached_class_file);
2481 _cached_class_file = NULL;
2482 }
2483 #endif
2484
2485 // Decrement symbol reference counts associated with the unloaded class.
2486 if (_name != NULL) _name->decrement_refcount();
2487 // unreference array name derived from this class name (arrays of an unloaded
2488 // class can't be referenced anymore).
2489 if (_array_name != NULL) _array_name->decrement_refcount();
2490 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2491 }
2492
2493 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2494 if (array == NULL) {
2495 _source_debug_extension = NULL;
2496 } else {
2497 // Adding one to the attribute length in order to store a null terminator
2498 // character could cause an overflow because the attribute length is
2499 // already coded with an u4 in the classfile, but in practice, it's
2500 // unlikely to happen.
2501 assert((length+1) > length, "Overflow checking");
2502 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2503 for (int i = 0; i < length; i++) {
2504 sde[i] = array[i];
2505 }
2506 sde[length] = '\0';
2507 _source_debug_extension = sde;
2508 }
2509 }
2510
2511 const char* InstanceKlass::signature_name() const {
2512 int hash_len = 0;
2513 char hash_buf[40];
2514
2515 // If this is an unsafe anonymous class, append a hash to make the name unique
2516 if (is_unsafe_anonymous()) {
2517 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2518 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2519 hash_len = (int)strlen(hash_buf);
2520 }
2521
2522 // Get the internal name as a c string
2523 const char* src = (const char*) (name()->as_C_string());
2524 const int src_length = (int)strlen(src);
2525
2526 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2527
2528 // Add L as type indicator
2529 int dest_index = 0;
2530 dest[dest_index++] = 'L';
2531
2532 // Add the actual class name
2533 for (int src_index = 0; src_index < src_length; ) {
2534 dest[dest_index++] = src[src_index++];
2535 }
2536
2537 // If we have a hash, append it
2538 for (int hash_index = 0; hash_index < hash_len; ) {
2539 dest[dest_index++] = hash_buf[hash_index++];
2540 }
2541
2542 // Add the semicolon and the NULL
2543 dest[dest_index++] = ';';
2544 dest[dest_index] = '\0';
2545 return dest;
2546 }
2547
2548 // Used to obtain the package name from a fully qualified class name.
2549 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2550 if (name == NULL) {
2551 return NULL;
2552 } else {
2553 if (name->utf8_length() <= 0) {
2554 return NULL;
2555 }
2556 ResourceMark rm;
2557 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2558 if (package_name == NULL) {
2559 return NULL;
2560 }
2561 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2562 return pkg_name;
2563 }
2564 }
2565
2566 ModuleEntry* InstanceKlass::module() const {
2567 // For an unsafe anonymous class return the host class' module
2568 if (is_unsafe_anonymous()) {
2569 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2570 return unsafe_anonymous_host()->module();
2571 }
2572
2573 // Class is in a named package
2574 if (!in_unnamed_package()) {
2575 return _package_entry->module();
2576 }
2577
2578 // Class is in an unnamed package, return its loader's unnamed module
2579 return class_loader_data()->unnamed_module();
2580 }
2581
2582 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2583
2584 // ensure java/ packages only loaded by boot or platform builtin loaders
2585 check_prohibited_package(name(), loader_data, CHECK);
2586
2587 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2588
2589 if (pkg_name != NULL && loader_data != NULL) {
2590
2591 // Find in class loader's package entry table.
2592 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2593
2594 // If the package name is not found in the loader's package
2595 // entry table, it is an indication that the package has not
2596 // been defined. Consider it defined within the unnamed module.
2597 if (_package_entry == NULL) {
2598 ResourceMark rm;
2599
2600 if (!ModuleEntryTable::javabase_defined()) {
2601 // Before java.base is defined during bootstrapping, define all packages in
2602 // the java.base module. If a non-java.base package is erroneously placed
2603 // in the java.base module it will be caught later when java.base
2604 // is defined by ModuleEntryTable::verify_javabase_packages check.
2605 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2606 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2607 } else {
2608 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2609 _package_entry = loader_data->packages()->lookup(pkg_name,
2610 loader_data->unnamed_module());
2611 }
2612
2613 // A package should have been successfully created
2614 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2615 name()->as_C_string(), loader_data->loader_name_and_id());
2616 }
2617
2618 if (log_is_enabled(Debug, module)) {
2619 ResourceMark rm;
2620 ModuleEntry* m = _package_entry->module();
2621 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2622 external_name(),
2623 pkg_name->as_C_string(),
2624 loader_data->loader_name_and_id(),
2625 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2626 }
2627 } else {
2628 ResourceMark rm;
2629 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2630 external_name(),
2631 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2632 UNNAMED_MODULE);
2633 }
2634 }
2635
2636
2637 // different versions of is_same_class_package
2638
2639 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2640 oop classloader1 = this->class_loader();
2641 PackageEntry* classpkg1 = this->package();
2642 if (class2->is_objArray_klass()) {
2643 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2644 }
2645
2646 oop classloader2;
2647 PackageEntry* classpkg2;
2648 if (class2->is_instance_klass()) {
2649 classloader2 = class2->class_loader();
2650 classpkg2 = class2->package();
2651 } else {
2652 assert(class2->is_typeArray_klass(), "should be type array");
2653 classloader2 = NULL;
2654 classpkg2 = NULL;
2655 }
2656
2657 // Same package is determined by comparing class loader
2658 // and package entries. Both must be the same. This rule
2659 // applies even to classes that are defined in the unnamed
2660 // package, they still must have the same class loader.
2661 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2662 return true;
2663 }
2664
2665 return false;
2666 }
2667
2668 // return true if this class and other_class are in the same package. Classloader
2669 // and classname information is enough to determine a class's package
2670 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2671 const Symbol* other_class_name) const {
2672 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2673 return false;
2674 }
2675 if (name()->fast_compare(other_class_name) == 0) {
2676 return true;
2677 }
2678
2679 {
2680 ResourceMark rm;
2681
2682 bool bad_class_name = false;
2683 const char* other_pkg =
2684 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2685 if (bad_class_name) {
2686 return false;
2687 }
2688 // Check that package_from_name() returns NULL, not "", if there is no package.
2689 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2690
2691 const Symbol* const this_package_name =
2692 this->package() != NULL ? this->package()->name() : NULL;
2693
2694 if (this_package_name == NULL || other_pkg == NULL) {
2695 // One of the two doesn't have a package. Only return true if the other
2696 // one also doesn't have a package.
2697 return (const char*)this_package_name == other_pkg;
2698 }
2699
2700 // Check if package is identical
2701 return this_package_name->equals(other_pkg);
2702 }
2703 }
2704
2705 // Returns true iff super_method can be overridden by a method in targetclassname
2706 // See JLS 3rd edition 8.4.6.1
2707 // Assumes name-signature match
2708 // "this" is InstanceKlass of super_method which must exist
2709 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2710 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2711 // Private methods can not be overridden
2712 if (super_method->is_private()) {
2713 return false;
2714 }
2715 // If super method is accessible, then override
2716 if ((super_method->is_protected()) ||
2717 (super_method->is_public())) {
2718 return true;
2719 }
2720 // Package-private methods are not inherited outside of package
2721 assert(super_method->is_package_private(), "must be package private");
2722 return(is_same_class_package(targetclassloader(), targetclassname));
2723 }
2724
2725 // Only boot and platform class loaders can define classes in "java/" packages.
2726 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2727 ClassLoaderData* loader_data,
2728 TRAPS) {
2729 if (!loader_data->is_boot_class_loader_data() &&
2730 !loader_data->is_platform_class_loader_data() &&
2731 class_name != NULL) {
2732 ResourceMark rm(THREAD);
2733 char* name = class_name->as_C_string();
2734 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2735 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2736 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2737 name = pkg_name->as_C_string();
2738 const char* class_loader_name = loader_data->loader_name_and_id();
2739 StringUtils::replace_no_expand(name, "/", ".");
2740 const char* msg_text1 = "Class loader (instance of): ";
2741 const char* msg_text2 = " tried to load prohibited package name: ";
2742 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2743 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2744 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2745 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2746 }
2747 }
2748 return;
2749 }
2750
2751 // tell if two classes have the same enclosing class (at package level)
2752 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2753 if (class2 == this) return true;
2754 if (!class2->is_instance_klass()) return false;
2755
2756 // must be in same package before we try anything else
2757 if (!is_same_class_package(class2))
2758 return false;
2759
2760 // As long as there is an outer_this.getEnclosingClass,
2761 // shift the search outward.
2762 const InstanceKlass* outer_this = this;
2763 for (;;) {
2764 // As we walk along, look for equalities between outer_this and class2.
2765 // Eventually, the walks will terminate as outer_this stops
2766 // at the top-level class around the original class.
2767 bool ignore_inner_is_member;
2768 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2769 CHECK_false);
2770 if (next == NULL) break;
2771 if (next == class2) return true;
2772 outer_this = InstanceKlass::cast(next);
2773 }
2774
2775 // Now do the same for class2.
2776 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2777 for (;;) {
2778 bool ignore_inner_is_member;
2779 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2780 CHECK_false);
2781 if (next == NULL) break;
2782 // Might as well check the new outer against all available values.
2783 if (next == this) return true;
2784 if (next == outer_this) return true;
2785 outer2 = InstanceKlass::cast(next);
2786 }
2787
2788 // If by this point we have not found an equality between the
2789 // two classes, we know they are in separate package members.
2790 return false;
2791 }
2792
2793 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2794 constantPoolHandle i_cp(THREAD, constants());
2795 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2796 int ioff = iter.inner_class_info_index();
2797 if (ioff != 0) {
2798 // Check to see if the name matches the class we're looking for
2799 // before attempting to find the class.
2800 if (i_cp->klass_name_at_matches(this, ioff)) {
2801 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2802 if (this == inner_klass) {
2803 *ooff = iter.outer_class_info_index();
2804 *noff = iter.inner_name_index();
2805 return true;
2806 }
2807 }
2808 }
2809 }
2810 return false;
2811 }
2812
2813 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2814 InstanceKlass* outer_klass = NULL;
2815 *inner_is_member = false;
2816 int ooff = 0, noff = 0;
2817 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2818 if (has_inner_classes_attr) {
2819 constantPoolHandle i_cp(THREAD, constants());
2820 if (ooff != 0) {
2821 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2822 outer_klass = InstanceKlass::cast(ok);
2823 *inner_is_member = true;
2824 }
2825 if (NULL == outer_klass) {
2826 // It may be unsafe anonymous; try for that.
2827 int encl_method_class_idx = enclosing_method_class_index();
2828 if (encl_method_class_idx != 0) {
2829 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2830 outer_klass = InstanceKlass::cast(ok);
2831 *inner_is_member = false;
2832 }
2833 }
2834 }
2835
2836 // If no inner class attribute found for this class.
2837 if (NULL == outer_klass) return NULL;
2838
2839 // Throws an exception if outer klass has not declared k as an inner klass
2840 // We need evidence that each klass knows about the other, or else
2841 // the system could allow a spoof of an inner class to gain access rights.
2842 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2843 return outer_klass;
2844 }
2845
2846 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2847 jint access = access_flags().as_int();
2848
2849 // But check if it happens to be member class.
2850 InnerClassesIterator iter(this);
2851 for (; !iter.done(); iter.next()) {
2852 int ioff = iter.inner_class_info_index();
2853 // Inner class attribute can be zero, skip it.
2854 // Strange but true: JVM spec. allows null inner class refs.
2855 if (ioff == 0) continue;
2856
2857 // only look at classes that are already loaded
2858 // since we are looking for the flags for our self.
2859 Symbol* inner_name = constants()->klass_name_at(ioff);
2860 if (name() == inner_name) {
2861 // This is really a member class.
2862 access = iter.inner_access_flags();
2863 break;
2864 }
2865 }
2866 // Remember to strip ACC_SUPER bit
2867 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2868 }
2869
2870 jint InstanceKlass::jvmti_class_status() const {
2871 jint result = 0;
2872
2873 if (is_linked()) {
2874 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2875 }
2876
2877 if (is_initialized()) {
2878 assert(is_linked(), "Class status is not consistent");
2879 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2880 }
2881 if (is_in_error_state()) {
2882 result |= JVMTI_CLASS_STATUS_ERROR;
2883 }
2884 return result;
2885 }
2886
2887 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2888 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2889 int method_table_offset_in_words = ioe->offset()/wordSize;
2890 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2891 / itableOffsetEntry::size();
2892
2893 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2894 // If the interface isn't implemented by the receiver class,
2895 // the VM should throw IncompatibleClassChangeError.
2896 if (cnt >= nof_interfaces) {
2897 ResourceMark rm(THREAD);
2898 stringStream ss;
2899 bool same_module = (module() == holder->module());
2900 ss.print("Receiver class %s does not implement "
2901 "the interface %s defining the method to be called "
2902 "(%s%s%s)",
2903 external_name(), holder->external_name(),
2904 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2905 (same_module) ? "" : "; ",
2906 (same_module) ? "" : holder->class_in_module_of_loader());
2907 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2908 }
2909
2910 Klass* ik = ioe->interface_klass();
2911 if (ik == holder) break;
2912 }
2913
2914 itableMethodEntry* ime = ioe->first_method_entry(this);
2915 Method* m = ime[index].method();
2916 if (m == NULL) {
2917 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2918 }
2919 return m;
2920 }
2921
2922
2923 #if INCLUDE_JVMTI
2924 // update default_methods for redefineclasses for methods that are
2925 // not yet in the vtable due to concurrent subclass define and superinterface
2926 // redefinition
2927 // Note: those in the vtable, should have been updated via adjust_method_entries
2928 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2929 // search the default_methods for uses of either obsolete or EMCP methods
2930 if (default_methods() != NULL) {
2931 for (int index = 0; index < default_methods()->length(); index ++) {
2932 Method* old_method = default_methods()->at(index);
2933 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2934 continue; // skip uninteresting entries
2935 }
2936 assert(!old_method->is_deleted(), "default methods may not be deleted");
2937
2938 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2939
2940 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2941 assert(old_method != new_method, "sanity check");
2942
2943 default_methods()->at_put(index, new_method);
2944 if (log_is_enabled(Info, redefine, class, update)) {
2945 ResourceMark rm;
2946 if (!(*trace_name_printed)) {
2947 log_info(redefine, class, update)
2948 ("adjust: klassname=%s default methods from name=%s",
2949 external_name(), old_method->method_holder()->external_name());
2950 *trace_name_printed = true;
2951 }
2952 log_debug(redefine, class, update, vtables)
2953 ("default method update: %s(%s) ",
2954 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2955 }
2956 }
2957 }
2958 }
2959 #endif // INCLUDE_JVMTI
2960
2961 // On-stack replacement stuff
2962 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2963 // only one compilation can be active
2964 {
2965 // This is a short non-blocking critical region, so the no safepoint check is ok.
2966 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2967 assert(n->is_osr_method(), "wrong kind of nmethod");
2968 n->set_osr_link(osr_nmethods_head());
2969 set_osr_nmethods_head(n);
2970 // Raise the highest osr level if necessary
2971 if (TieredCompilation) {
2972 Method* m = n->method();
2973 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2974 }
2975 }
2976
2977 // Get rid of the osr methods for the same bci that have lower levels.
2978 if (TieredCompilation) {
2979 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2980 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2981 if (inv != NULL && inv->is_in_use()) {
2982 inv->make_not_entrant();
2983 }
2984 }
2985 }
2986 }
2987
2988 // Remove osr nmethod from the list. Return true if found and removed.
2989 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2990 // This is a short non-blocking critical region, so the no safepoint check is ok.
2991 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2992 assert(n->is_osr_method(), "wrong kind of nmethod");
2993 nmethod* last = NULL;
2994 nmethod* cur = osr_nmethods_head();
2995 int max_level = CompLevel_none; // Find the max comp level excluding n
2996 Method* m = n->method();
2997 // Search for match
2998 bool found = false;
2999 while(cur != NULL && cur != n) {
3000 if (TieredCompilation && m == cur->method()) {
3001 // Find max level before n
3002 max_level = MAX2(max_level, cur->comp_level());
3003 }
3004 last = cur;
3005 cur = cur->osr_link();
3006 }
3007 nmethod* next = NULL;
3008 if (cur == n) {
3009 found = true;
3010 next = cur->osr_link();
3011 if (last == NULL) {
3012 // Remove first element
3013 set_osr_nmethods_head(next);
3014 } else {
3015 last->set_osr_link(next);
3016 }
3017 }
3018 n->set_osr_link(NULL);
3019 if (TieredCompilation) {
3020 cur = next;
3021 while (cur != NULL) {
3022 // Find max level after n
3023 if (m == cur->method()) {
3024 max_level = MAX2(max_level, cur->comp_level());
3025 }
3026 cur = cur->osr_link();
3027 }
3028 m->set_highest_osr_comp_level(max_level);
3029 }
3030 return found;
3031 }
3032
3033 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3034 // This is a short non-blocking critical region, so the no safepoint check is ok.
3035 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3036 nmethod* osr = osr_nmethods_head();
3037 int found = 0;
3038 while (osr != NULL) {
3039 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3040 if (osr->method() == m) {
3041 osr->mark_for_deoptimization();
3042 found++;
3043 }
3044 osr = osr->osr_link();
3045 }
3046 return found;
3047 }
3048
3049 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3050 // This is a short non-blocking critical region, so the no safepoint check is ok.
3051 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3052 nmethod* osr = osr_nmethods_head();
3053 nmethod* best = NULL;
3054 while (osr != NULL) {
3055 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3056 // There can be a time when a c1 osr method exists but we are waiting
3057 // for a c2 version. When c2 completes its osr nmethod we will trash
3058 // the c1 version and only be able to find the c2 version. However
3059 // while we overflow in the c1 code at back branches we don't want to
3060 // try and switch to the same code as we are already running
3061
3062 if (osr->method() == m &&
3063 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3064 if (match_level) {
3065 if (osr->comp_level() == comp_level) {
3066 // Found a match - return it.
3067 return osr;
3068 }
3069 } else {
3070 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3071 if (osr->comp_level() == CompLevel_highest_tier) {
3072 // Found the best possible - return it.
3073 return osr;
3074 }
3075 best = osr;
3076 }
3077 }
3078 }
3079 osr = osr->osr_link();
3080 }
3081 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3082 return best;
3083 }
3084 return NULL;
3085 }
3086
3087 // -----------------------------------------------------------------------------------------------------
3088 // Printing
3089
3090 #ifndef PRODUCT
3091
3092 #define BULLET " - "
3093
3094 static const char* state_names[] = {
3095 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3096 };
3097
3098 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3099 for (int i = 0; i < len; i++) {
3100 intptr_t e = start[i];
3101 st->print("%d : " INTPTR_FORMAT, i, e);
3102 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3103 st->print(" ");
3104 ((Metadata*)e)->print_value_on(st);
3105 }
3106 st->cr();
3107 }
3108 }
3109
3110 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3111 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3112 }
3113
3114 void InstanceKlass::print_on(outputStream* st) const {
3115 assert(is_klass(), "must be klass");
3116 Klass::print_on(st);
3117
3118 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3119 st->print(BULLET"klass size: %d", size()); st->cr();
3120 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3121 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3122 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3123 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3124 st->print(BULLET"sub: ");
3125 Klass* sub = subklass();
3126 int n;
3127 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3128 if (n < MaxSubklassPrintSize) {
3129 sub->print_value_on(st);
3130 st->print(" ");
3131 }
3132 }
3133 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3134 st->cr();
3135
3136 if (is_interface()) {
3137 MutexLocker ml(Compile_lock);
3138 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3139 if (nof_implementors() == 1) {
3140 st->print_cr(BULLET"implementor: ");
3141 st->print(" ");
3142 implementor()->print_value_on(st);
3143 st->cr();
3144 }
3145 }
3146
3147 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3148 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3149 if (Verbose || WizardMode) {
3150 Array<Method*>* method_array = methods();
3151 for (int i = 0; i < method_array->length(); i++) {
3152 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3153 }
3154 }
3155 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3156 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3157 if (Verbose && default_methods() != NULL) {
3158 Array<Method*>* method_array = default_methods();
3159 for (int i = 0; i < method_array->length(); i++) {
3160 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3161 }
3162 }
3163 if (default_vtable_indices() != NULL) {
3164 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3165 }
3166 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3167 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3168 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3169 if (class_loader_data() != NULL) {
3170 st->print(BULLET"class loader data: ");
3171 class_loader_data()->print_value_on(st);
3172 st->cr();
3173 }
3174 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3175 if (source_file_name() != NULL) {
3176 st->print(BULLET"source file: ");
3177 source_file_name()->print_value_on(st);
3178 st->cr();
3179 }
3180 if (source_debug_extension() != NULL) {
3181 st->print(BULLET"source debug extension: ");
3182 st->print("%s", source_debug_extension());
3183 st->cr();
3184 }
3185 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3186 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3187 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3188 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3189 {
3190 bool have_pv = false;
3191 // previous versions are linked together through the InstanceKlass
3192 for (InstanceKlass* pv_node = previous_versions();
3193 pv_node != NULL;
3194 pv_node = pv_node->previous_versions()) {
3195 if (!have_pv)
3196 st->print(BULLET"previous version: ");
3197 have_pv = true;
3198 pv_node->constants()->print_value_on(st);
3199 }
3200 if (have_pv) st->cr();
3201 }
3202
3203 if (generic_signature() != NULL) {
3204 st->print(BULLET"generic signature: ");
3205 generic_signature()->print_value_on(st);
3206 st->cr();
3207 }
3208 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3209 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3210 if (java_mirror() != NULL) {
3211 st->print(BULLET"java mirror: ");
3212 java_mirror()->print_value_on(st);
3213 st->cr();
3214 } else {
3215 st->print_cr(BULLET"java mirror: NULL");
3216 }
3217 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3218 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3219 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3220 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3221 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3222 FieldPrinter print_static_field(st);
3223 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3224 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3225 FieldPrinter print_nonstatic_field(st);
3226 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3227 ik->do_nonstatic_fields(&print_nonstatic_field);
3228
3229 st->print(BULLET"non-static oop maps: ");
3230 OopMapBlock* map = start_of_nonstatic_oop_maps();
3231 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3232 while (map < end_map) {
3233 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3234 map++;
3235 }
3236 st->cr();
3237 }
3238
3239 #endif //PRODUCT
3240
3241 void InstanceKlass::print_value_on(outputStream* st) const {
3242 assert(is_klass(), "must be klass");
3243 if (Verbose || WizardMode) access_flags().print_on(st);
3244 name()->print_value_on(st);
3245 }
3246
3247 #ifndef PRODUCT
3248
3249 void FieldPrinter::do_field(fieldDescriptor* fd) {
3250 _st->print(BULLET);
3251 if (_obj == NULL) {
3252 fd->print_on(_st);
3253 _st->cr();
3254 } else {
3255 fd->print_on_for(_st, _obj);
3256 _st->cr();
3257 }
3258 }
3259
3260
3261 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3262 Klass::oop_print_on(obj, st);
3263
3264 if (this == SystemDictionary::String_klass()) {
3265 typeArrayOop value = java_lang_String::value(obj);
3266 juint length = java_lang_String::length(obj);
3267 if (value != NULL &&
3268 value->is_typeArray() &&
3269 length <= (juint) value->length()) {
3270 st->print(BULLET"string: ");
3271 java_lang_String::print(obj, st);
3272 st->cr();
3273 if (!WizardMode) return; // that is enough
3274 }
3275 }
3276
3277 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3278 FieldPrinter print_field(st, obj);
3279 do_nonstatic_fields(&print_field);
3280
3281 if (this == SystemDictionary::Class_klass()) {
3282 st->print(BULLET"signature: ");
3283 java_lang_Class::print_signature(obj, st);
3284 st->cr();
3285 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3286 st->print(BULLET"fake entry for mirror: ");
3287 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3288 st->cr();
3289 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3290 st->print(BULLET"fake entry for array: ");
3291 Metadata::print_value_on_maybe_null(st, array_klass);
3292 st->cr();
3293 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3294 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3295 Klass* real_klass = java_lang_Class::as_Klass(obj);
3296 if (real_klass != NULL && real_klass->is_instance_klass()) {
3297 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3298 }
3299 } else if (this == SystemDictionary::MethodType_klass()) {
3300 st->print(BULLET"signature: ");
3301 java_lang_invoke_MethodType::print_signature(obj, st);
3302 st->cr();
3303 }
3304 }
3305
3306 bool InstanceKlass::verify_itable_index(int i) {
3307 int method_count = klassItable::method_count_for_interface(this);
3308 assert(i >= 0 && i < method_count, "index out of bounds");
3309 return true;
3310 }
3311
3312 #endif //PRODUCT
3313
3314 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3315 st->print("a ");
3316 name()->print_value_on(st);
3317 obj->print_address_on(st);
3318 if (this == SystemDictionary::String_klass()
3319 && java_lang_String::value(obj) != NULL) {
3320 ResourceMark rm;
3321 int len = java_lang_String::length(obj);
3322 int plen = (len < 24 ? len : 12);
3323 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3324 st->print(" = \"%s\"", str);
3325 if (len > plen)
3326 st->print("...[%d]", len);
3327 } else if (this == SystemDictionary::Class_klass()) {
3328 Klass* k = java_lang_Class::as_Klass(obj);
3329 st->print(" = ");
3330 if (k != NULL) {
3331 k->print_value_on(st);
3332 } else {
3333 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3334 st->print("%s", tname ? tname : "type?");
3335 }
3336 } else if (this == SystemDictionary::MethodType_klass()) {
3337 st->print(" = ");
3338 java_lang_invoke_MethodType::print_signature(obj, st);
3339 } else if (java_lang_boxing_object::is_instance(obj)) {
3340 st->print(" = ");
3341 java_lang_boxing_object::print(obj, st);
3342 } else if (this == SystemDictionary::LambdaForm_klass()) {
3343 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3344 if (vmentry != NULL) {
3345 st->print(" => ");
3346 vmentry->print_value_on(st);
3347 }
3348 } else if (this == SystemDictionary::MemberName_klass()) {
3349 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3350 if (vmtarget != NULL) {
3351 st->print(" = ");
3352 vmtarget->print_value_on(st);
3353 } else {
3354 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3355 st->print(".");
3356 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3357 }
3358 }
3359 }
3360
3361 const char* InstanceKlass::internal_name() const {
3362 return external_name();
3363 }
3364
3365 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3366 const char* module_name,
3367 const ClassFileStream* cfs) const {
3368 if (!log_is_enabled(Info, class, load)) {
3369 return;
3370 }
3371
3372 ResourceMark rm;
3373 LogMessage(class, load) msg;
3374 stringStream info_stream;
3375
3376 // Name and class hierarchy info
3377 info_stream.print("%s", external_name());
3378
3379 // Source
3380 if (cfs != NULL) {
3381 if (cfs->source() != NULL) {
3382 if (module_name != NULL) {
3383 if (ClassLoader::is_modules_image(cfs->source())) {
3384 info_stream.print(" source: jrt:/%s", module_name);
3385 } else {
3386 info_stream.print(" source: %s", cfs->source());
3387 }
3388 } else {
3389 info_stream.print(" source: %s", cfs->source());
3390 }
3391 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3392 Thread* THREAD = Thread::current();
3393 Klass* caller =
3394 THREAD->is_Java_thread()
3395 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3396 : NULL;
3397 // caller can be NULL, for example, during a JVMTI VM_Init hook
3398 if (caller != NULL) {
3399 info_stream.print(" source: instance of %s", caller->external_name());
3400 } else {
3401 // source is unknown
3402 }
3403 } else {
3404 oop class_loader = loader_data->class_loader();
3405 info_stream.print(" source: %s", class_loader->klass()->external_name());
3406 }
3407 } else {
3408 info_stream.print(" source: shared objects file");
3409 }
3410
3411 msg.info("%s", info_stream.as_string());
3412
3413 if (log_is_enabled(Debug, class, load)) {
3414 stringStream debug_stream;
3415
3416 // Class hierarchy info
3417 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3418 p2i(this), p2i(superklass()));
3419
3420 // Interfaces
3421 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3422 debug_stream.print(" interfaces:");
3423 int length = local_interfaces()->length();
3424 for (int i = 0; i < length; i++) {
3425 debug_stream.print(" " INTPTR_FORMAT,
3426 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3427 }
3428 }
3429
3430 // Class loader
3431 debug_stream.print(" loader: [");
3432 loader_data->print_value_on(&debug_stream);
3433 debug_stream.print("]");
3434
3435 // Classfile checksum
3436 if (cfs) {
3437 debug_stream.print(" bytes: %d checksum: %08x",
3438 cfs->length(),
3439 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3440 cfs->length()));
3441 }
3442
3443 msg.debug("%s", debug_stream.as_string());
3444 }
3445 }
3446
3447 #if INCLUDE_SERVICES
3448 // Size Statistics
3449 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3450 Klass::collect_statistics(sz);
3451
3452 sz->_inst_size = wordSize * size_helper();
3453 sz->_vtab_bytes = wordSize * vtable_length();
3454 sz->_itab_bytes = wordSize * itable_length();
3455 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3456
3457 int n = 0;
3458 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3459 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3460 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3461 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3462 n += (sz->_fields_bytes = sz->count_array(fields()));
3463 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3464 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3465 sz->_ro_bytes += n;
3466
3467 const ConstantPool* cp = constants();
3468 if (cp) {
3469 cp->collect_statistics(sz);
3470 }
3471
3472 const Annotations* anno = annotations();
3473 if (anno) {
3474 anno->collect_statistics(sz);
3475 }
3476
3477 const Array<Method*>* methods_array = methods();
3478 if (methods()) {
3479 for (int i = 0; i < methods_array->length(); i++) {
3480 Method* method = methods_array->at(i);
3481 if (method) {
3482 sz->_method_count ++;
3483 method->collect_statistics(sz);
3484 }
3485 }
3486 }
3487 }
3488 #endif // INCLUDE_SERVICES
3489
3490 // Verification
3491
3492 class VerifyFieldClosure: public BasicOopIterateClosure {
3493 protected:
3494 template <class T> void do_oop_work(T* p) {
3495 oop obj = RawAccess<>::oop_load(p);
3496 if (!oopDesc::is_oop_or_null(obj)) {
3497 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3498 Universe::print_on(tty);
3499 guarantee(false, "boom");
3500 }
3501 }
3502 public:
3503 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3504 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3505 };
3506
3507 void InstanceKlass::verify_on(outputStream* st) {
3508 #ifndef PRODUCT
3509 // Avoid redundant verifies, this really should be in product.
3510 if (_verify_count == Universe::verify_count()) return;
3511 _verify_count = Universe::verify_count();
3512 #endif
3513
3514 // Verify Klass
3515 Klass::verify_on(st);
3516
3517 // Verify that klass is present in ClassLoaderData
3518 guarantee(class_loader_data()->contains_klass(this),
3519 "this class isn't found in class loader data");
3520
3521 // Verify vtables
3522 if (is_linked()) {
3523 // $$$ This used to be done only for m/s collections. Doing it
3524 // always seemed a valid generalization. (DLD -- 6/00)
3525 vtable().verify(st);
3526 }
3527
3528 // Verify first subklass
3529 if (subklass() != NULL) {
3530 guarantee(subklass()->is_klass(), "should be klass");
3531 }
3532
3533 // Verify siblings
3534 Klass* super = this->super();
3535 Klass* sib = next_sibling();
3536 if (sib != NULL) {
3537 if (sib == this) {
3538 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3539 }
3540
3541 guarantee(sib->is_klass(), "should be klass");
3542 guarantee(sib->super() == super, "siblings should have same superklass");
3543 }
3544
3545 // Verify implementor fields requires the Compile_lock, but this is sometimes
3546 // called inside a safepoint, so don't verify.
3547
3548 // Verify local interfaces
3549 if (local_interfaces()) {
3550 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3551 for (int j = 0; j < local_interfaces->length(); j++) {
3552 InstanceKlass* e = local_interfaces->at(j);
3553 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3554 }
3555 }
3556
3557 // Verify transitive interfaces
3558 if (transitive_interfaces() != NULL) {
3559 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3560 for (int j = 0; j < transitive_interfaces->length(); j++) {
3561 InstanceKlass* e = transitive_interfaces->at(j);
3562 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3563 }
3564 }
3565
3566 // Verify methods
3567 if (methods() != NULL) {
3568 Array<Method*>* methods = this->methods();
3569 for (int j = 0; j < methods->length(); j++) {
3570 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3571 }
3572 for (int j = 0; j < methods->length() - 1; j++) {
3573 Method* m1 = methods->at(j);
3574 Method* m2 = methods->at(j + 1);
3575 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3576 }
3577 }
3578
3579 // Verify method ordering
3580 if (method_ordering() != NULL) {
3581 Array<int>* method_ordering = this->method_ordering();
3582 int length = method_ordering->length();
3583 if (JvmtiExport::can_maintain_original_method_order() ||
3584 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3585 guarantee(length == methods()->length(), "invalid method ordering length");
3586 jlong sum = 0;
3587 for (int j = 0; j < length; j++) {
3588 int original_index = method_ordering->at(j);
3589 guarantee(original_index >= 0, "invalid method ordering index");
3590 guarantee(original_index < length, "invalid method ordering index");
3591 sum += original_index;
3592 }
3593 // Verify sum of indices 0,1,...,length-1
3594 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3595 } else {
3596 guarantee(length == 0, "invalid method ordering length");
3597 }
3598 }
3599
3600 // Verify default methods
3601 if (default_methods() != NULL) {
3602 Array<Method*>* methods = this->default_methods();
3603 for (int j = 0; j < methods->length(); j++) {
3604 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3605 }
3606 for (int j = 0; j < methods->length() - 1; j++) {
3607 Method* m1 = methods->at(j);
3608 Method* m2 = methods->at(j + 1);
3609 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3610 }
3611 }
3612
3613 // Verify JNI static field identifiers
3614 if (jni_ids() != NULL) {
3615 jni_ids()->verify(this);
3616 }
3617
3618 // Verify other fields
3619 if (array_klasses() != NULL) {
3620 guarantee(array_klasses()->is_klass(), "should be klass");
3621 }
3622 if (constants() != NULL) {
3623 guarantee(constants()->is_constantPool(), "should be constant pool");
3624 }
3625 const Klass* anonymous_host = unsafe_anonymous_host();
3626 if (anonymous_host != NULL) {
3627 guarantee(anonymous_host->is_klass(), "should be klass");
3628 }
3629 }
3630
3631 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3632 Klass::oop_verify_on(obj, st);
3633 VerifyFieldClosure blk;
3634 obj->oop_iterate(&blk);
3635 }
3636
3637
3638 // JNIid class for jfieldIDs only
3639 // Note to reviewers:
3640 // These JNI functions are just moved over to column 1 and not changed
3641 // in the compressed oops workspace.
3642 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3643 _holder = holder;
3644 _offset = offset;
3645 _next = next;
3646 debug_only(_is_static_field_id = false;)
3647 }
3648
3649
3650 JNIid* JNIid::find(int offset) {
3651 JNIid* current = this;
3652 while (current != NULL) {
3653 if (current->offset() == offset) return current;
3654 current = current->next();
3655 }
3656 return NULL;
3657 }
3658
3659 void JNIid::deallocate(JNIid* current) {
3660 while (current != NULL) {
3661 JNIid* next = current->next();
3662 delete current;
3663 current = next;
3664 }
3665 }
3666
3667
3668 void JNIid::verify(Klass* holder) {
3669 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3670 int end_field_offset;
3671 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3672
3673 JNIid* current = this;
3674 while (current != NULL) {
3675 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3676 #ifdef ASSERT
3677 int o = current->offset();
3678 if (current->is_static_field_id()) {
3679 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3680 }
3681 #endif
3682 current = current->next();
3683 }
3684 }
3685
3686 #ifdef ASSERT
3687 void InstanceKlass::set_init_state(ClassState state) {
3688 bool good_state = is_shared() ? (_init_state <= state)
3689 : (_init_state < state);
3690 assert(good_state || state == allocated, "illegal state transition");
3691 _init_state = (u1)state;
3692 }
3693 #endif
3694
3695 #if INCLUDE_JVMTI
3696
3697 // RedefineClasses() support for previous versions
3698
3699 // Globally, there is at least one previous version of a class to walk
3700 // during class unloading, which is saved because old methods in the class
3701 // are still running. Otherwise the previous version list is cleaned up.
3702 bool InstanceKlass::_has_previous_versions = false;
3703
3704 // Returns true if there are previous versions of a class for class
3705 // unloading only. Also resets the flag to false. purge_previous_version
3706 // will set the flag to true if there are any left, i.e., if there's any
3707 // work to do for next time. This is to avoid the expensive code cache
3708 // walk in CLDG::clean_deallocate_lists().
3709 bool InstanceKlass::has_previous_versions_and_reset() {
3710 bool ret = _has_previous_versions;
3711 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3712 ret ? "true" : "false");
3713 _has_previous_versions = false;
3714 return ret;
3715 }
3716
3717 // Purge previous versions before adding new previous versions of the class and
3718 // during class unloading.
3719 void InstanceKlass::purge_previous_version_list() {
3720 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3721 assert(has_been_redefined(), "Should only be called for main class");
3722
3723 // Quick exit.
3724 if (previous_versions() == NULL) {
3725 return;
3726 }
3727
3728 // This klass has previous versions so see what we can cleanup
3729 // while it is safe to do so.
3730
3731 int deleted_count = 0; // leave debugging breadcrumbs
3732 int live_count = 0;
3733 ClassLoaderData* loader_data = class_loader_data();
3734 assert(loader_data != NULL, "should never be null");
3735
3736 ResourceMark rm;
3737 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3738
3739 // previous versions are linked together through the InstanceKlass
3740 InstanceKlass* pv_node = previous_versions();
3741 InstanceKlass* last = this;
3742 int version = 0;
3743
3744 // check the previous versions list
3745 for (; pv_node != NULL; ) {
3746
3747 ConstantPool* pvcp = pv_node->constants();
3748 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3749
3750 if (!pvcp->on_stack()) {
3751 // If the constant pool isn't on stack, none of the methods
3752 // are executing. Unlink this previous_version.
3753 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3754 // so will be deallocated during the next phase of class unloading.
3755 log_trace(redefine, class, iklass, purge)
3756 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3757 // For debugging purposes.
3758 pv_node->set_is_scratch_class();
3759 // Unlink from previous version list.
3760 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3761 InstanceKlass* next = pv_node->previous_versions();
3762 pv_node->link_previous_versions(NULL); // point next to NULL
3763 last->link_previous_versions(next);
3764 // Add to the deallocate list after unlinking
3765 loader_data->add_to_deallocate_list(pv_node);
3766 pv_node = next;
3767 deleted_count++;
3768 version++;
3769 continue;
3770 } else {
3771 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3772 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3773 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3774 live_count++;
3775 // found a previous version for next time we do class unloading
3776 _has_previous_versions = true;
3777 }
3778
3779 // At least one method is live in this previous version.
3780 // Reset dead EMCP methods not to get breakpoints.
3781 // All methods are deallocated when all of the methods for this class are no
3782 // longer running.
3783 Array<Method*>* method_refs = pv_node->methods();
3784 if (method_refs != NULL) {
3785 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3786 for (int j = 0; j < method_refs->length(); j++) {
3787 Method* method = method_refs->at(j);
3788
3789 if (!method->on_stack()) {
3790 // no breakpoints for non-running methods
3791 if (method->is_running_emcp()) {
3792 method->set_running_emcp(false);
3793 }
3794 } else {
3795 assert (method->is_obsolete() || method->is_running_emcp(),
3796 "emcp method cannot run after emcp bit is cleared");
3797 log_trace(redefine, class, iklass, purge)
3798 ("purge: %s(%s): prev method @%d in version @%d is alive",
3799 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3800 }
3801 }
3802 }
3803 // next previous version
3804 last = pv_node;
3805 pv_node = pv_node->previous_versions();
3806 version++;
3807 }
3808 log_trace(redefine, class, iklass, purge)
3809 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3810 }
3811
3812 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3813 int emcp_method_count) {
3814 int obsolete_method_count = old_methods->length() - emcp_method_count;
3815
3816 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3817 _previous_versions != NULL) {
3818 // We have a mix of obsolete and EMCP methods so we have to
3819 // clear out any matching EMCP method entries the hard way.
3820 int local_count = 0;
3821 for (int i = 0; i < old_methods->length(); i++) {
3822 Method* old_method = old_methods->at(i);
3823 if (old_method->is_obsolete()) {
3824 // only obsolete methods are interesting
3825 Symbol* m_name = old_method->name();
3826 Symbol* m_signature = old_method->signature();
3827
3828 // previous versions are linked together through the InstanceKlass
3829 int j = 0;
3830 for (InstanceKlass* prev_version = _previous_versions;
3831 prev_version != NULL;
3832 prev_version = prev_version->previous_versions(), j++) {
3833
3834 Array<Method*>* method_refs = prev_version->methods();
3835 for (int k = 0; k < method_refs->length(); k++) {
3836 Method* method = method_refs->at(k);
3837
3838 if (!method->is_obsolete() &&
3839 method->name() == m_name &&
3840 method->signature() == m_signature) {
3841 // The current RedefineClasses() call has made all EMCP
3842 // versions of this method obsolete so mark it as obsolete
3843 log_trace(redefine, class, iklass, add)
3844 ("%s(%s): flush obsolete method @%d in version @%d",
3845 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3846
3847 method->set_is_obsolete();
3848 break;
3849 }
3850 }
3851
3852 // The previous loop may not find a matching EMCP method, but
3853 // that doesn't mean that we can optimize and not go any
3854 // further back in the PreviousVersion generations. The EMCP
3855 // method for this generation could have already been made obsolete,
3856 // but there still may be an older EMCP method that has not
3857 // been made obsolete.
3858 }
3859
3860 if (++local_count >= obsolete_method_count) {
3861 // no more obsolete methods so bail out now
3862 break;
3863 }
3864 }
3865 }
3866 }
3867 }
3868
3869 // Save the scratch_class as the previous version if any of the methods are running.
3870 // The previous_versions are used to set breakpoints in EMCP methods and they are
3871 // also used to clean MethodData links to redefined methods that are no longer running.
3872 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3873 int emcp_method_count) {
3874 assert(Thread::current()->is_VM_thread(),
3875 "only VMThread can add previous versions");
3876
3877 ResourceMark rm;
3878 log_trace(redefine, class, iklass, add)
3879 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3880
3881 // Clean out old previous versions for this class
3882 purge_previous_version_list();
3883
3884 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3885 // a previous redefinition may be made obsolete by this redefinition.
3886 Array<Method*>* old_methods = scratch_class->methods();
3887 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3888
3889 // If the constant pool for this previous version of the class
3890 // is not marked as being on the stack, then none of the methods
3891 // in this previous version of the class are on the stack so
3892 // we don't need to add this as a previous version.
3893 ConstantPool* cp_ref = scratch_class->constants();
3894 if (!cp_ref->on_stack()) {
3895 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3896 // For debugging purposes.
3897 scratch_class->set_is_scratch_class();
3898 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3899 return;
3900 }
3901
3902 if (emcp_method_count != 0) {
3903 // At least one method is still running, check for EMCP methods
3904 for (int i = 0; i < old_methods->length(); i++) {
3905 Method* old_method = old_methods->at(i);
3906 if (!old_method->is_obsolete() && old_method->on_stack()) {
3907 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3908 // we can add breakpoints for it.
3909
3910 // We set the method->on_stack bit during safepoints for class redefinition
3911 // and use this bit to set the is_running_emcp bit.
3912 // After the safepoint, the on_stack bit is cleared and the running emcp
3913 // method may exit. If so, we would set a breakpoint in a method that
3914 // is never reached, but this won't be noticeable to the programmer.
3915 old_method->set_running_emcp(true);
3916 log_trace(redefine, class, iklass, add)
3917 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3918 } else if (!old_method->is_obsolete()) {
3919 log_trace(redefine, class, iklass, add)
3920 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3921 }
3922 }
3923 }
3924
3925 // Add previous version if any methods are still running.
3926 // Set has_previous_version flag for processing during class unloading.
3927 _has_previous_versions = true;
3928 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3929 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3930 scratch_class->link_previous_versions(previous_versions());
3931 link_previous_versions(scratch_class);
3932 } // end add_previous_version()
3933
3934 #endif // INCLUDE_JVMTI
3935
3936 Method* InstanceKlass::method_with_idnum(int idnum) {
3937 Method* m = NULL;
3938 if (idnum < methods()->length()) {
3939 m = methods()->at(idnum);
3940 }
3941 if (m == NULL || m->method_idnum() != idnum) {
3942 for (int index = 0; index < methods()->length(); ++index) {
3943 m = methods()->at(index);
3944 if (m->method_idnum() == idnum) {
3945 return m;
3946 }
3947 }
3948 // None found, return null for the caller to handle.
3949 return NULL;
3950 }
3951 return m;
3952 }
3953
3954
3955 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3956 if (idnum >= methods()->length()) {
3957 return NULL;
3958 }
3959 Method* m = methods()->at(idnum);
3960 if (m != NULL && m->orig_method_idnum() == idnum) {
3961 return m;
3962 }
3963 // Obsolete method idnum does not match the original idnum
3964 for (int index = 0; index < methods()->length(); ++index) {
3965 m = methods()->at(index);
3966 if (m->orig_method_idnum() == idnum) {
3967 return m;
3968 }
3969 }
3970 // None found, return null for the caller to handle.
3971 return NULL;
3972 }
3973
3974
3975 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3976 InstanceKlass* holder = get_klass_version(version);
3977 if (holder == NULL) {
3978 return NULL; // The version of klass is gone, no method is found
3979 }
3980 Method* method = holder->method_with_orig_idnum(idnum);
3981 return method;
3982 }
3983
3984 #if INCLUDE_JVMTI
3985 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3986 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3987 // Ignore the archived class stream data
3988 return NULL;
3989 } else {
3990 return _cached_class_file;
3991 }
3992 }
3993
3994 jint InstanceKlass::get_cached_class_file_len() {
3995 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3996 }
3997
3998 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3999 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4000 }
4001
4002 #if INCLUDE_CDS
4003 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
4004 if (DumpSharedSpaces) {
4005 return _cached_class_file;
4006 } else {
4007 assert(this->is_shared(), "class should be shared");
4008 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
4009 return _cached_class_file;
4010 } else {
4011 return NULL;
4012 }
4013 }
4014 }
4015 #endif
4016 #endif