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 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1217 int size = objArrayOopDesc::object_size(length);
1218 Klass* ak = array_klass(n, CHECK_NULL);
1219 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1220 /* do_zero */ true, CHECK_NULL);
1221 return o;
1222 }
1223
1224 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1225 if (TraceFinalizerRegistration) {
1226 tty->print("Registered ");
1227 i->print_value_on(tty);
1228 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1229 }
1230 instanceHandle h_i(THREAD, i);
1231 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1232 JavaValue result(T_VOID);
1233 JavaCallArguments args(h_i);
1234 methodHandle mh (THREAD, Universe::finalizer_register_method());
1235 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1236 return h_i();
1237 }
1238
1239 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1240 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1241 int size = size_helper(); // Query before forming handle.
1242
1243 instanceOop i;
1244
1245 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1246 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1247 i = register_finalizer(i, CHECK_NULL);
1248 }
1249 return i;
1250 }
1251
1252 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1253 return instanceHandle(THREAD, allocate_instance(THREAD));
1254 }
1255
1256 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1257 if (is_interface() || is_abstract()) {
1258 ResourceMark rm(THREAD);
1259 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1260 : vmSymbols::java_lang_InstantiationException(), external_name());
1261 }
1262 if (this == SystemDictionary::Class_klass()) {
1263 ResourceMark rm(THREAD);
1264 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1265 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1266 }
1267 }
1268
1269 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1270 // Need load-acquire for lock-free read
1271 if (array_klasses_acquire() == NULL) {
1272 if (or_null) return NULL;
1273
1274 ResourceMark rm;
1275 JavaThread *jt = (JavaThread *)THREAD;
1276 {
1277 // Atomic creation of array_klasses
1278 MutexLocker mc(Compile_lock, THREAD); // for vtables
1279 MutexLocker ma(MultiArray_lock, THREAD);
1280
1281 // Check if update has already taken place
1282 if (array_klasses() == NULL) {
1283 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1284 // use 'release' to pair with lock-free load
1285 release_set_array_klasses(k);
1286 }
1287 }
1288 }
1289 // _this will always be set at this point
1290 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1291 if (or_null) {
1292 return oak->array_klass_or_null(n);
1293 }
1294 return oak->array_klass(n, THREAD);
1295 }
1296
1297 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1298 return array_klass_impl(or_null, 1, THREAD);
1299 }
1300
1301 static int call_class_initializer_counter = 0; // for debugging
1302
1303 Method* InstanceKlass::class_initializer() const {
1304 Method* clinit = find_method(
1305 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1306 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1307 return clinit;
1308 }
1309 return NULL;
1310 }
1311
1312 void InstanceKlass::call_class_initializer(TRAPS) {
1313 if (ReplayCompiles &&
1314 (ReplaySuppressInitializers == 1 ||
1315 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1316 // Hide the existence of the initializer for the purpose of replaying the compile
1317 return;
1318 }
1319
1320 methodHandle h_method(THREAD, class_initializer());
1321 assert(!is_initialized(), "we cannot initialize twice");
1322 LogTarget(Info, class, init) lt;
1323 if (lt.is_enabled()) {
1324 ResourceMark rm;
1325 LogStream ls(lt);
1326 ls.print("%d Initializing ", call_class_initializer_counter++);
1327 name()->print_value_on(&ls);
1328 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1329 }
1330 if (h_method() != NULL) {
1331 JavaCallArguments args; // No arguments
1332 JavaValue result(T_VOID);
1333 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1334 }
1335 }
1336
1337
1338 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1339 InterpreterOopMap* entry_for) {
1340 // Lazily create the _oop_map_cache at first request
1341 // Lock-free access requires load_acquire.
1342 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1343 if (oop_map_cache == NULL) {
1344 MutexLocker x(OopMapCacheAlloc_lock);
1345 // Check if _oop_map_cache was allocated while we were waiting for this lock
1346 if ((oop_map_cache = _oop_map_cache) == NULL) {
1347 oop_map_cache = new OopMapCache();
1348 // Ensure _oop_map_cache is stable, since it is examined without a lock
1349 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1350 }
1351 }
1352 // _oop_map_cache is constant after init; lookup below does its own locking.
1353 oop_map_cache->lookup(method, bci, entry_for);
1354 }
1355
1356
1357 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1358 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1359 Symbol* f_name = fs.name();
1360 Symbol* f_sig = fs.signature();
1361 if (f_name == name && f_sig == sig) {
1362 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1363 return true;
1364 }
1365 }
1366 return false;
1367 }
1368
1369
1370 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1371 const int n = local_interfaces()->length();
1372 for (int i = 0; i < n; i++) {
1373 Klass* intf1 = local_interfaces()->at(i);
1374 assert(intf1->is_interface(), "just checking type");
1375 // search for field in current interface
1376 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1377 assert(fd->is_static(), "interface field must be static");
1378 return intf1;
1379 }
1380 // search for field in direct superinterfaces
1381 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1382 if (intf2 != NULL) return intf2;
1383 }
1384 // otherwise field lookup fails
1385 return NULL;
1386 }
1387
1388
1389 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1390 // search order according to newest JVM spec (5.4.3.2, p.167).
1391 // 1) search for field in current klass
1392 if (find_local_field(name, sig, fd)) {
1393 return const_cast<InstanceKlass*>(this);
1394 }
1395 // 2) search for field recursively in direct superinterfaces
1396 { Klass* intf = find_interface_field(name, sig, fd);
1397 if (intf != NULL) return intf;
1398 }
1399 // 3) apply field lookup recursively if superclass exists
1400 { Klass* supr = super();
1401 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1402 }
1403 // 4) otherwise field lookup fails
1404 return NULL;
1405 }
1406
1407
1408 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1409 // search order according to newest JVM spec (5.4.3.2, p.167).
1410 // 1) search for field in current klass
1411 if (find_local_field(name, sig, fd)) {
1412 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1413 }
1414 // 2) search for field recursively in direct superinterfaces
1415 if (is_static) {
1416 Klass* intf = find_interface_field(name, sig, fd);
1417 if (intf != NULL) return intf;
1418 }
1419 // 3) apply field lookup recursively if superclass exists
1420 { Klass* supr = super();
1421 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1422 }
1423 // 4) otherwise field lookup fails
1424 return NULL;
1425 }
1426
1427
1428 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1429 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1430 if (fs.offset() == offset) {
1431 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1432 if (fd->is_static() == is_static) return true;
1433 }
1434 }
1435 return false;
1436 }
1437
1438
1439 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1440 Klass* klass = const_cast<InstanceKlass*>(this);
1441 while (klass != NULL) {
1442 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1443 return true;
1444 }
1445 klass = klass->super();
1446 }
1447 return false;
1448 }
1449
1450
1451 void InstanceKlass::methods_do(void f(Method* method)) {
1452 // Methods aren't stable until they are loaded. This can be read outside
1453 // a lock through the ClassLoaderData for profiling
1454 if (!is_loaded()) {
1455 return;
1456 }
1457
1458 int len = methods()->length();
1459 for (int index = 0; index < len; index++) {
1460 Method* m = methods()->at(index);
1461 assert(m->is_method(), "must be method");
1462 f(m);
1463 }
1464 }
1465
1466
1467 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1468 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1469 if (fs.access_flags().is_static()) {
1470 fieldDescriptor& fd = fs.field_descriptor();
1471 cl->do_field(&fd);
1472 }
1473 }
1474 }
1475
1476
1477 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1478 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1479 if (fs.access_flags().is_static()) {
1480 fieldDescriptor& fd = fs.field_descriptor();
1481 f(&fd, mirror, CHECK);
1482 }
1483 }
1484 }
1485
1486
1487 static int compare_fields_by_offset(int* a, int* b) {
1488 return a[0] - b[0];
1489 }
1490
1491 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1492 InstanceKlass* super = superklass();
1493 if (super != NULL) {
1494 super->do_nonstatic_fields(cl);
1495 }
1496 fieldDescriptor fd;
1497 int length = java_fields_count();
1498 // In DebugInfo nonstatic fields are sorted by offset.
1499 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1500 int j = 0;
1501 for (int i = 0; i < length; i += 1) {
1502 fd.reinitialize(this, i);
1503 if (!fd.is_static()) {
1504 fields_sorted[j + 0] = fd.offset();
1505 fields_sorted[j + 1] = i;
1506 j += 2;
1507 }
1508 }
1509 if (j > 0) {
1510 length = j;
1511 // _sort_Fn is defined in growableArray.hpp.
1512 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1513 for (int i = 0; i < length; i += 2) {
1514 fd.reinitialize(this, fields_sorted[i + 1]);
1515 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1516 cl->do_field(&fd);
1517 }
1518 }
1519 FREE_C_HEAP_ARRAY(int, fields_sorted);
1520 }
1521
1522
1523 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1524 if (array_klasses() != NULL)
1525 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1526 }
1527
1528 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1529 if (array_klasses() != NULL)
1530 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1531 }
1532
1533 #ifdef ASSERT
1534 static int linear_search(const Array<Method*>* methods,
1535 const Symbol* name,
1536 const Symbol* signature) {
1537 const int len = methods->length();
1538 for (int index = 0; index < len; index++) {
1539 const Method* const m = methods->at(index);
1540 assert(m->is_method(), "must be method");
1541 if (m->signature() == signature && m->name() == name) {
1542 return index;
1543 }
1544 }
1545 return -1;
1546 }
1547 #endif
1548
1549 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1550 int len = methods->length();
1551 // methods are sorted, so do binary search
1552 int l = 0;
1553 int h = len - 1;
1554 while (l <= h) {
1555 int mid = (l + h) >> 1;
1556 Method* m = methods->at(mid);
1557 assert(m->is_method(), "must be method");
1558 int res = m->name()->fast_compare(name);
1559 if (res == 0) {
1560 return mid;
1561 } else if (res < 0) {
1562 l = mid + 1;
1563 } else {
1564 h = mid - 1;
1565 }
1566 }
1567 return -1;
1568 }
1569
1570 // find_method looks up the name/signature in the local methods array
1571 Method* InstanceKlass::find_method(const Symbol* name,
1572 const Symbol* signature) const {
1573 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1574 }
1575
1576 Method* InstanceKlass::find_method_impl(const Symbol* name,
1577 const Symbol* signature,
1578 OverpassLookupMode overpass_mode,
1579 StaticLookupMode static_mode,
1580 PrivateLookupMode private_mode) const {
1581 return InstanceKlass::find_method_impl(methods(),
1582 name,
1583 signature,
1584 overpass_mode,
1585 static_mode,
1586 private_mode);
1587 }
1588
1589 // find_instance_method looks up the name/signature in the local methods array
1590 // and skips over static methods
1591 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1592 const Symbol* name,
1593 const Symbol* signature,
1594 PrivateLookupMode private_mode) {
1595 Method* const meth = InstanceKlass::find_method_impl(methods,
1596 name,
1597 signature,
1598 find_overpass,
1599 skip_static,
1600 private_mode);
1601 assert(((meth == NULL) || !meth->is_static()),
1602 "find_instance_method should have skipped statics");
1603 return meth;
1604 }
1605
1606 // find_instance_method looks up the name/signature in the local methods array
1607 // and skips over static methods
1608 Method* InstanceKlass::find_instance_method(const Symbol* name,
1609 const Symbol* signature,
1610 PrivateLookupMode private_mode) const {
1611 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1612 }
1613
1614 // Find looks up the name/signature in the local methods array
1615 // and filters on the overpass, static and private flags
1616 // This returns the first one found
1617 // note that the local methods array can have up to one overpass, one static
1618 // and one instance (private or not) with the same name/signature
1619 Method* InstanceKlass::find_local_method(const Symbol* name,
1620 const Symbol* signature,
1621 OverpassLookupMode overpass_mode,
1622 StaticLookupMode static_mode,
1623 PrivateLookupMode private_mode) const {
1624 return InstanceKlass::find_method_impl(methods(),
1625 name,
1626 signature,
1627 overpass_mode,
1628 static_mode,
1629 private_mode);
1630 }
1631
1632 // Find looks up the name/signature in the local methods array
1633 // and filters on the overpass, static and private flags
1634 // This returns the first one found
1635 // note that the local methods array can have up to one overpass, one static
1636 // and one instance (private or not) with the same name/signature
1637 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1638 const Symbol* name,
1639 const Symbol* signature,
1640 OverpassLookupMode overpass_mode,
1641 StaticLookupMode static_mode,
1642 PrivateLookupMode private_mode) {
1643 return InstanceKlass::find_method_impl(methods,
1644 name,
1645 signature,
1646 overpass_mode,
1647 static_mode,
1648 private_mode);
1649 }
1650
1651 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1652 const Symbol* name,
1653 const Symbol* signature) {
1654 return InstanceKlass::find_method_impl(methods,
1655 name,
1656 signature,
1657 find_overpass,
1658 find_static,
1659 find_private);
1660 }
1661
1662 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1663 const Symbol* name,
1664 const Symbol* signature,
1665 OverpassLookupMode overpass_mode,
1666 StaticLookupMode static_mode,
1667 PrivateLookupMode private_mode) {
1668 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1669 return hit >= 0 ? methods->at(hit): NULL;
1670 }
1671
1672 // true if method matches signature and conforms to skipping_X conditions.
1673 static bool method_matches(const Method* m,
1674 const Symbol* signature,
1675 bool skipping_overpass,
1676 bool skipping_static,
1677 bool skipping_private) {
1678 return ((m->signature() == signature) &&
1679 (!skipping_overpass || !m->is_overpass()) &&
1680 (!skipping_static || !m->is_static()) &&
1681 (!skipping_private || !m->is_private()));
1682 }
1683
1684 // Used directly for default_methods to find the index into the
1685 // default_vtable_indices, and indirectly by find_method
1686 // find_method_index looks in the local methods array to return the index
1687 // of the matching name/signature. If, overpass methods are being ignored,
1688 // the search continues to find a potential non-overpass match. This capability
1689 // is important during method resolution to prefer a static method, for example,
1690 // over an overpass method.
1691 // There is the possibility in any _method's array to have the same name/signature
1692 // for a static method, an overpass method and a local instance method
1693 // To correctly catch a given method, the search criteria may need
1694 // to explicitly skip the other two. For local instance methods, it
1695 // is often necessary to skip private methods
1696 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1697 const Symbol* name,
1698 const Symbol* signature,
1699 OverpassLookupMode overpass_mode,
1700 StaticLookupMode static_mode,
1701 PrivateLookupMode private_mode) {
1702 const bool skipping_overpass = (overpass_mode == skip_overpass);
1703 const bool skipping_static = (static_mode == skip_static);
1704 const bool skipping_private = (private_mode == skip_private);
1705 const int hit = binary_search(methods, name);
1706 if (hit != -1) {
1707 const Method* const m = methods->at(hit);
1708
1709 // Do linear search to find matching signature. First, quick check
1710 // for common case, ignoring overpasses if requested.
1711 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1712 return hit;
1713 }
1714
1715 // search downwards through overloaded methods
1716 int i;
1717 for (i = hit - 1; i >= 0; --i) {
1718 const Method* const m = methods->at(i);
1719 assert(m->is_method(), "must be method");
1720 if (m->name() != name) {
1721 break;
1722 }
1723 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1724 return i;
1725 }
1726 }
1727 // search upwards
1728 for (i = hit + 1; i < methods->length(); ++i) {
1729 const Method* const m = methods->at(i);
1730 assert(m->is_method(), "must be method");
1731 if (m->name() != name) {
1732 break;
1733 }
1734 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1735 return i;
1736 }
1737 }
1738 // not found
1739 #ifdef ASSERT
1740 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1741 linear_search(methods, name, signature);
1742 assert(-1 == index, "binary search should have found entry %d", index);
1743 #endif
1744 }
1745 return -1;
1746 }
1747
1748 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1749 return find_method_by_name(methods(), name, end);
1750 }
1751
1752 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1753 const Symbol* name,
1754 int* end_ptr) {
1755 assert(end_ptr != NULL, "just checking");
1756 int start = binary_search(methods, name);
1757 int end = start + 1;
1758 if (start != -1) {
1759 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1760 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1761 *end_ptr = end;
1762 return start;
1763 }
1764 return -1;
1765 }
1766
1767 // uncached_lookup_method searches both the local class methods array and all
1768 // superclasses methods arrays, skipping any overpass methods in superclasses,
1769 // and possibly skipping private methods.
1770 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1771 const Symbol* signature,
1772 OverpassLookupMode overpass_mode,
1773 PrivateLookupMode private_mode) const {
1774 OverpassLookupMode overpass_local_mode = overpass_mode;
1775 const Klass* klass = this;
1776 while (klass != NULL) {
1777 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1778 signature,
1779 overpass_local_mode,
1780 find_static,
1781 private_mode);
1782 if (method != NULL) {
1783 return method;
1784 }
1785 klass = klass->super();
1786 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1787 }
1788 return NULL;
1789 }
1790
1791 #ifdef ASSERT
1792 // search through class hierarchy and return true if this class or
1793 // one of the superclasses was redefined
1794 bool InstanceKlass::has_redefined_this_or_super() const {
1795 const Klass* klass = this;
1796 while (klass != NULL) {
1797 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1798 return true;
1799 }
1800 klass = klass->super();
1801 }
1802 return false;
1803 }
1804 #endif
1805
1806 // lookup a method in the default methods list then in all transitive interfaces
1807 // Do NOT return private or static methods
1808 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1809 Symbol* signature) const {
1810 Method* m = NULL;
1811 if (default_methods() != NULL) {
1812 m = find_method(default_methods(), name, signature);
1813 }
1814 // Look up interfaces
1815 if (m == NULL) {
1816 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1817 }
1818 return m;
1819 }
1820
1821 // lookup a method in all the interfaces that this class implements
1822 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1823 // They should only be found in the initial InterfaceMethodRef
1824 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1825 Symbol* signature,
1826 DefaultsLookupMode defaults_mode) const {
1827 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1828 int num_ifs = all_ifs->length();
1829 InstanceKlass *ik = NULL;
1830 for (int i = 0; i < num_ifs; i++) {
1831 ik = all_ifs->at(i);
1832 Method* m = ik->lookup_method(name, signature);
1833 if (m != NULL && m->is_public() && !m->is_static() &&
1834 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1835 return m;
1836 }
1837 }
1838 return NULL;
1839 }
1840
1841 /* jni_id_for_impl for jfieldIds only */
1842 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1843 MutexLocker ml(JfieldIdCreation_lock);
1844 // Retry lookup after we got the lock
1845 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1846 if (probe == NULL) {
1847 // Slow case, allocate new static field identifier
1848 probe = new JNIid(this, offset, jni_ids());
1849 set_jni_ids(probe);
1850 }
1851 return probe;
1852 }
1853
1854
1855 /* jni_id_for for jfieldIds only */
1856 JNIid* InstanceKlass::jni_id_for(int offset) {
1857 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1858 if (probe == NULL) {
1859 probe = jni_id_for_impl(offset);
1860 }
1861 return probe;
1862 }
1863
1864 u2 InstanceKlass::enclosing_method_data(int offset) const {
1865 const Array<jushort>* const inner_class_list = inner_classes();
1866 if (inner_class_list == NULL) {
1867 return 0;
1868 }
1869 const int length = inner_class_list->length();
1870 if (length % inner_class_next_offset == 0) {
1871 return 0;
1872 }
1873 const int index = length - enclosing_method_attribute_size;
1874 assert(offset < enclosing_method_attribute_size, "invalid offset");
1875 return inner_class_list->at(index + offset);
1876 }
1877
1878 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1879 u2 method_index) {
1880 Array<jushort>* inner_class_list = inner_classes();
1881 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1882 int length = inner_class_list->length();
1883 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1884 int index = length - enclosing_method_attribute_size;
1885 inner_class_list->at_put(
1886 index + enclosing_method_class_index_offset, class_index);
1887 inner_class_list->at_put(
1888 index + enclosing_method_method_index_offset, method_index);
1889 }
1890 }
1891
1892 // Lookup or create a jmethodID.
1893 // This code is called by the VMThread and JavaThreads so the
1894 // locking has to be done very carefully to avoid deadlocks
1895 // and/or other cache consistency problems.
1896 //
1897 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1898 size_t idnum = (size_t)method_h->method_idnum();
1899 jmethodID* jmeths = methods_jmethod_ids_acquire();
1900 size_t length = 0;
1901 jmethodID id = NULL;
1902
1903 // We use a double-check locking idiom here because this cache is
1904 // performance sensitive. In the normal system, this cache only
1905 // transitions from NULL to non-NULL which is safe because we use
1906 // release_set_methods_jmethod_ids() to advertise the new cache.
1907 // A partially constructed cache should never be seen by a racing
1908 // thread. We also use release_store() to save a new jmethodID
1909 // in the cache so a partially constructed jmethodID should never be
1910 // seen either. Cache reads of existing jmethodIDs proceed without a
1911 // lock, but cache writes of a new jmethodID requires uniqueness and
1912 // creation of the cache itself requires no leaks so a lock is
1913 // generally acquired in those two cases.
1914 //
1915 // If the RedefineClasses() API has been used, then this cache can
1916 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1917 // Cache creation requires no leaks and we require safety between all
1918 // cache accesses and freeing of the old cache so a lock is generally
1919 // acquired when the RedefineClasses() API has been used.
1920
1921 if (jmeths != NULL) {
1922 // the cache already exists
1923 if (!idnum_can_increment()) {
1924 // the cache can't grow so we can just get the current values
1925 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1926 } else {
1927 // cache can grow so we have to be more careful
1928 if (Threads::number_of_threads() == 0 ||
1929 SafepointSynchronize::is_at_safepoint()) {
1930 // we're single threaded or at a safepoint - no locking needed
1931 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1932 } else {
1933 MutexLocker ml(JmethodIdCreation_lock);
1934 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1935 }
1936 }
1937 }
1938 // implied else:
1939 // we need to allocate a cache so default length and id values are good
1940
1941 if (jmeths == NULL || // no cache yet
1942 length <= idnum || // cache is too short
1943 id == NULL) { // cache doesn't contain entry
1944
1945 // This function can be called by the VMThread so we have to do all
1946 // things that might block on a safepoint before grabbing the lock.
1947 // Otherwise, we can deadlock with the VMThread or have a cache
1948 // consistency issue. These vars keep track of what we might have
1949 // to free after the lock is dropped.
1950 jmethodID to_dealloc_id = NULL;
1951 jmethodID* to_dealloc_jmeths = NULL;
1952
1953 // may not allocate new_jmeths or use it if we allocate it
1954 jmethodID* new_jmeths = NULL;
1955 if (length <= idnum) {
1956 // allocate a new cache that might be used
1957 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1958 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1959 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1960 // cache size is stored in element[0], other elements offset by one
1961 new_jmeths[0] = (jmethodID)size;
1962 }
1963
1964 // allocate a new jmethodID that might be used
1965 jmethodID new_id = NULL;
1966 if (method_h->is_old() && !method_h->is_obsolete()) {
1967 // The method passed in is old (but not obsolete), we need to use the current version
1968 Method* current_method = method_with_idnum((int)idnum);
1969 assert(current_method != NULL, "old and but not obsolete, so should exist");
1970 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1971 } else {
1972 // It is the current version of the method or an obsolete method,
1973 // use the version passed in
1974 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1975 }
1976
1977 if (Threads::number_of_threads() == 0 ||
1978 SafepointSynchronize::is_at_safepoint()) {
1979 // we're single threaded or at a safepoint - no locking needed
1980 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1981 &to_dealloc_id, &to_dealloc_jmeths);
1982 } else {
1983 MutexLocker ml(JmethodIdCreation_lock);
1984 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1985 &to_dealloc_id, &to_dealloc_jmeths);
1986 }
1987
1988 // The lock has been dropped so we can free resources.
1989 // Free up either the old cache or the new cache if we allocated one.
1990 if (to_dealloc_jmeths != NULL) {
1991 FreeHeap(to_dealloc_jmeths);
1992 }
1993 // free up the new ID since it wasn't needed
1994 if (to_dealloc_id != NULL) {
1995 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1996 }
1997 }
1998 return id;
1999 }
2000
2001 // Figure out how many jmethodIDs haven't been allocated, and make
2002 // sure space for them is pre-allocated. This makes getting all
2003 // method ids much, much faster with classes with more than 8
2004 // methods, and has a *substantial* effect on performance with jvmti
2005 // code that loads all jmethodIDs for all classes.
2006 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2007 int new_jmeths = 0;
2008 int length = methods()->length();
2009 for (int index = start_offset; index < length; index++) {
2010 Method* m = methods()->at(index);
2011 jmethodID id = m->find_jmethod_id_or_null();
2012 if (id == NULL) {
2013 new_jmeths++;
2014 }
2015 }
2016 if (new_jmeths != 0) {
2017 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2018 }
2019 }
2020
2021 // Common code to fetch the jmethodID from the cache or update the
2022 // cache with the new jmethodID. This function should never do anything
2023 // that causes the caller to go to a safepoint or we can deadlock with
2024 // the VMThread or have cache consistency issues.
2025 //
2026 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2027 size_t idnum, jmethodID new_id,
2028 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2029 jmethodID** to_dealloc_jmeths_p) {
2030 assert(new_id != NULL, "sanity check");
2031 assert(to_dealloc_id_p != NULL, "sanity check");
2032 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2033 assert(Threads::number_of_threads() == 0 ||
2034 SafepointSynchronize::is_at_safepoint() ||
2035 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2036
2037 // reacquire the cache - we are locked, single threaded or at a safepoint
2038 jmethodID* jmeths = methods_jmethod_ids_acquire();
2039 jmethodID id = NULL;
2040 size_t length = 0;
2041
2042 if (jmeths == NULL || // no cache yet
2043 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2044 if (jmeths != NULL) {
2045 // copy any existing entries from the old cache
2046 for (size_t index = 0; index < length; index++) {
2047 new_jmeths[index+1] = jmeths[index+1];
2048 }
2049 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2050 }
2051 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2052 } else {
2053 // fetch jmethodID (if any) from the existing cache
2054 id = jmeths[idnum+1];
2055 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2056 }
2057 if (id == NULL) {
2058 // No matching jmethodID in the existing cache or we have a new
2059 // cache or we just grew the cache. This cache write is done here
2060 // by the first thread to win the foot race because a jmethodID
2061 // needs to be unique once it is generally available.
2062 id = new_id;
2063
2064 // The jmethodID cache can be read while unlocked so we have to
2065 // make sure the new jmethodID is complete before installing it
2066 // in the cache.
2067 OrderAccess::release_store(&jmeths[idnum+1], id);
2068 } else {
2069 *to_dealloc_id_p = new_id; // save new id for later delete
2070 }
2071 return id;
2072 }
2073
2074
2075 // Common code to get the jmethodID cache length and the jmethodID
2076 // value at index idnum if there is one.
2077 //
2078 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2079 size_t idnum, size_t *length_p, jmethodID* id_p) {
2080 assert(cache != NULL, "sanity check");
2081 assert(length_p != NULL, "sanity check");
2082 assert(id_p != NULL, "sanity check");
2083
2084 // cache size is stored in element[0], other elements offset by one
2085 *length_p = (size_t)cache[0];
2086 if (*length_p <= idnum) { // cache is too short
2087 *id_p = NULL;
2088 } else {
2089 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2090 }
2091 }
2092
2093
2094 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2095 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2096 size_t idnum = (size_t)method->method_idnum();
2097 jmethodID* jmeths = methods_jmethod_ids_acquire();
2098 size_t length; // length assigned as debugging crumb
2099 jmethodID id = NULL;
2100 if (jmeths != NULL && // If there is a cache
2101 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2102 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2103 }
2104 return id;
2105 }
2106
2107 inline DependencyContext InstanceKlass::dependencies() {
2108 DependencyContext dep_context(&_dep_context);
2109 return dep_context;
2110 }
2111
2112 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2113 return dependencies().mark_dependent_nmethods(changes);
2114 }
2115
2116 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2117 dependencies().add_dependent_nmethod(nm);
2118 }
2119
2120 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2121 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2122 }
2123
2124 #ifndef PRODUCT
2125 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2126 dependencies().print_dependent_nmethods(verbose);
2127 }
2128
2129 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2130 return dependencies().is_dependent_nmethod(nm);
2131 }
2132 #endif //PRODUCT
2133
2134 void InstanceKlass::clean_weak_instanceklass_links() {
2135 clean_implementors_list();
2136 clean_method_data();
2137
2138 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2139 DependencyContext dep_context(&_dep_context);
2140 dep_context.expunge_stale_entries();
2141 }
2142
2143 void InstanceKlass::clean_implementors_list() {
2144 assert(is_loader_alive(), "this klass should be live");
2145 if (is_interface()) {
2146 if (ClassUnloading) {
2147 Klass* impl = implementor();
2148 if (impl != NULL) {
2149 if (!impl->is_loader_alive()) {
2150 // remove this guy
2151 Klass** klass = adr_implementor();
2152 assert(klass != NULL, "null klass");
2153 if (klass != NULL) {
2154 *klass = NULL;
2155 }
2156 }
2157 }
2158 }
2159 }
2160 }
2161
2162 void InstanceKlass::clean_method_data() {
2163 for (int m = 0; m < methods()->length(); m++) {
2164 MethodData* mdo = methods()->at(m)->method_data();
2165 if (mdo != NULL) {
2166 mdo->clean_method_data(/*always_clean*/false);
2167 }
2168 }
2169 }
2170
2171 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2172 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2173 ResourceMark rm;
2174 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2175 return false;
2176 }
2177
2178 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2179 if (local_interfaces != NULL) {
2180 int length = local_interfaces->length();
2181 for (int i = 0; i < length; i++) {
2182 InstanceKlass* intf = local_interfaces->at(i);
2183 if (!intf->has_passed_fingerprint_check()) {
2184 ResourceMark rm;
2185 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2186 return false;
2187 }
2188 }
2189 }
2190
2191 return true;
2192 }
2193
2194 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2195 #if INCLUDE_AOT
2196 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2197 if (CalculateClassFingerprint) {
2198 // (1) We are running AOT to generate a shared library.
2199 return true;
2200 }
2201 if (DumpSharedSpaces) {
2202 // (2) We are running -Xshare:dump to create a shared archive
2203 return true;
2204 }
2205 if (UseAOT && is_unsafe_anonymous) {
2206 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2207 return true;
2208 }
2209 #endif
2210
2211 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2212 // but do not store the 64-bit fingerprint to save space.
2213 return false;
2214 }
2215
2216 bool InstanceKlass::has_stored_fingerprint() const {
2217 #if INCLUDE_AOT
2218 return should_store_fingerprint() || is_shared();
2219 #else
2220 return false;
2221 #endif
2222 }
2223
2224 uint64_t InstanceKlass::get_stored_fingerprint() const {
2225 address adr = adr_fingerprint();
2226 if (adr != NULL) {
2227 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2228 }
2229 return 0;
2230 }
2231
2232 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2233 address adr = adr_fingerprint();
2234 if (adr != NULL) {
2235 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2236
2237 ResourceMark rm;
2238 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2239 }
2240 }
2241
2242 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2243 Klass::metaspace_pointers_do(it);
2244
2245 if (log_is_enabled(Trace, cds)) {
2246 ResourceMark rm;
2247 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2248 }
2249
2250 it->push(&_annotations);
2251 it->push((Klass**)&_array_klasses);
2252 it->push(&_constants);
2253 it->push(&_inner_classes);
2254 it->push(&_array_name);
2255 #if INCLUDE_JVMTI
2256 it->push(&_previous_versions);
2257 #endif
2258 it->push(&_methods);
2259 it->push(&_default_methods);
2260 it->push(&_local_interfaces);
2261 it->push(&_transitive_interfaces);
2262 it->push(&_method_ordering);
2263 it->push(&_default_vtable_indices);
2264 it->push(&_fields);
2265
2266 if (itable_length() > 0) {
2267 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2268 int method_table_offset_in_words = ioe->offset()/wordSize;
2269 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2270 / itableOffsetEntry::size();
2271
2272 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2273 if (ioe->interface_klass() != NULL) {
2274 it->push(ioe->interface_klass_addr());
2275 itableMethodEntry* ime = ioe->first_method_entry(this);
2276 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2277 for (int index = 0; index < n; index ++) {
2278 it->push(ime[index].method_addr());
2279 }
2280 }
2281 }
2282 }
2283
2284 it->push(&_nest_members);
2285 }
2286
2287 void InstanceKlass::remove_unshareable_info() {
2288 Klass::remove_unshareable_info();
2289
2290 if (is_in_error_state()) {
2291 // Classes are attempted to link during dumping and may fail,
2292 // but these classes are still in the dictionary and class list in CLD.
2293 // Check in_error state first because in_error is > linked state, so
2294 // is_linked() is true.
2295 // If there's a linking error, there is nothing else to remove.
2296 return;
2297 }
2298
2299 // Unlink the class
2300 if (is_linked()) {
2301 unlink_class();
2302 }
2303 {
2304 MutexLocker ml(Compile_lock);
2305 init_implementor();
2306 }
2307
2308 constants()->remove_unshareable_info();
2309
2310 for (int i = 0; i < methods()->length(); i++) {
2311 Method* m = methods()->at(i);
2312 m->remove_unshareable_info();
2313 }
2314
2315 // do array classes also.
2316 if (array_klasses() != NULL) {
2317 array_klasses()->remove_unshareable_info();
2318 }
2319
2320 // These are not allocated from metaspace, but they should should all be empty
2321 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2322 guarantee(_source_debug_extension == NULL, "must be");
2323 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2324 guarantee(_osr_nmethods_head == NULL, "must be");
2325
2326 #if INCLUDE_JVMTI
2327 guarantee(_breakpoints == NULL, "must be");
2328 guarantee(_previous_versions == NULL, "must be");
2329 #endif
2330
2331 _init_thread = NULL;
2332 _methods_jmethod_ids = NULL;
2333 _jni_ids = NULL;
2334 _oop_map_cache = NULL;
2335 // clear _nest_host to ensure re-load at runtime
2336 _nest_host = NULL;
2337 }
2338
2339 void InstanceKlass::remove_java_mirror() {
2340 Klass::remove_java_mirror();
2341
2342 // do array classes also.
2343 if (array_klasses() != NULL) {
2344 array_klasses()->remove_java_mirror();
2345 }
2346 }
2347
2348 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2349 set_package(loader_data, CHECK);
2350 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2351
2352 Array<Method*>* methods = this->methods();
2353 int num_methods = methods->length();
2354 for (int index2 = 0; index2 < num_methods; ++index2) {
2355 methodHandle m(THREAD, methods->at(index2));
2356 m->restore_unshareable_info(CHECK);
2357 }
2358 if (JvmtiExport::has_redefined_a_class()) {
2359 // Reinitialize vtable because RedefineClasses may have changed some
2360 // entries in this vtable for super classes so the CDS vtable might
2361 // point to old or obsolete entries. RedefineClasses doesn't fix up
2362 // vtables in the shared system dictionary, only the main one.
2363 // It also redefines the itable too so fix that too.
2364 vtable().initialize_vtable(false, CHECK);
2365 itable().initialize_itable(false, CHECK);
2366 }
2367
2368 // restore constant pool resolved references
2369 constants()->restore_unshareable_info(CHECK);
2370
2371 if (array_klasses() != NULL) {
2372 // Array classes have null protection domain.
2373 // --> see ArrayKlass::complete_create_array_klass()
2374 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2375 }
2376 }
2377
2378 // returns true IFF is_in_error_state() has been changed as a result of this call.
2379 bool InstanceKlass::check_sharing_error_state() {
2380 assert(DumpSharedSpaces, "should only be called during dumping");
2381 bool old_state = is_in_error_state();
2382
2383 if (!is_in_error_state()) {
2384 bool bad = false;
2385 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2386 if (sup->is_in_error_state()) {
2387 bad = true;
2388 break;
2389 }
2390 }
2391 if (!bad) {
2392 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2393 for (int i = 0; i < interfaces->length(); i++) {
2394 InstanceKlass* iface = interfaces->at(i);
2395 if (iface->is_in_error_state()) {
2396 bad = true;
2397 break;
2398 }
2399 }
2400 }
2401
2402 if (bad) {
2403 set_in_error_state();
2404 }
2405 }
2406
2407 return (old_state != is_in_error_state());
2408 }
2409
2410 #if INCLUDE_JVMTI
2411 static void clear_all_breakpoints(Method* m) {
2412 m->clear_all_breakpoints();
2413 }
2414 #endif
2415
2416 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2417 // notify the debugger
2418 if (JvmtiExport::should_post_class_unload()) {
2419 JvmtiExport::post_class_unload(ik);
2420 }
2421
2422 // notify ClassLoadingService of class unload
2423 ClassLoadingService::notify_class_unloaded(ik);
2424
2425 #if INCLUDE_JFR
2426 assert(ik != NULL, "invariant");
2427 EventClassUnload event;
2428 event.set_unloadedClass(ik);
2429 event.set_definingClassLoader(ik->class_loader_data());
2430 event.commit();
2431 #endif
2432 }
2433
2434 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2435 // Clean up C heap
2436 ik->release_C_heap_structures();
2437 ik->constants()->release_C_heap_structures();
2438 }
2439
2440 void InstanceKlass::release_C_heap_structures() {
2441 // Can't release the constant pool here because the constant pool can be
2442 // deallocated separately from the InstanceKlass for default methods and
2443 // redefine classes.
2444
2445 // Deallocate oop map cache
2446 if (_oop_map_cache != NULL) {
2447 delete _oop_map_cache;
2448 _oop_map_cache = NULL;
2449 }
2450
2451 // Deallocate JNI identifiers for jfieldIDs
2452 JNIid::deallocate(jni_ids());
2453 set_jni_ids(NULL);
2454
2455 jmethodID* jmeths = methods_jmethod_ids_acquire();
2456 if (jmeths != (jmethodID*)NULL) {
2457 release_set_methods_jmethod_ids(NULL);
2458 FreeHeap(jmeths);
2459 }
2460
2461 // Release dependencies.
2462 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2463 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2464 // context can contain live dependencies, since there's a race between nmethod &
2465 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2466 // dependencies aren't removed from the context associated with the class (see
2467 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2468 // live dependencies pointing to unloaded nmethods and causes a crash in
2469 // DC::remove_all_dependents() when it touches unloaded nmethod.
2470 dependencies().wipe();
2471
2472 #if INCLUDE_JVMTI
2473 // Deallocate breakpoint records
2474 if (breakpoints() != 0x0) {
2475 methods_do(clear_all_breakpoints);
2476 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2477 }
2478
2479 // deallocate the cached class file
2480 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2481 os::free(_cached_class_file);
2482 _cached_class_file = NULL;
2483 }
2484 #endif
2485
2486 // Decrement symbol reference counts associated with the unloaded class.
2487 if (_name != NULL) _name->decrement_refcount();
2488 // unreference array name derived from this class name (arrays of an unloaded
2489 // class can't be referenced anymore).
2490 if (_array_name != NULL) _array_name->decrement_refcount();
2491 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2492 }
2493
2494 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2495 if (array == NULL) {
2496 _source_debug_extension = NULL;
2497 } else {
2498 // Adding one to the attribute length in order to store a null terminator
2499 // character could cause an overflow because the attribute length is
2500 // already coded with an u4 in the classfile, but in practice, it's
2501 // unlikely to happen.
2502 assert((length+1) > length, "Overflow checking");
2503 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2504 for (int i = 0; i < length; i++) {
2505 sde[i] = array[i];
2506 }
2507 sde[length] = '\0';
2508 _source_debug_extension = sde;
2509 }
2510 }
2511
2512 const char* InstanceKlass::signature_name() const {
2513 int hash_len = 0;
2514 char hash_buf[40];
2515
2516 // If this is an unsafe anonymous class, append a hash to make the name unique
2517 if (is_unsafe_anonymous()) {
2518 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2519 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2520 hash_len = (int)strlen(hash_buf);
2521 }
2522
2523 // Get the internal name as a c string
2524 const char* src = (const char*) (name()->as_C_string());
2525 const int src_length = (int)strlen(src);
2526
2527 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2528
2529 // Add L as type indicator
2530 int dest_index = 0;
2531 dest[dest_index++] = 'L';
2532
2533 // Add the actual class name
2534 for (int src_index = 0; src_index < src_length; ) {
2535 dest[dest_index++] = src[src_index++];
2536 }
2537
2538 // If we have a hash, append it
2539 for (int hash_index = 0; hash_index < hash_len; ) {
2540 dest[dest_index++] = hash_buf[hash_index++];
2541 }
2542
2543 // Add the semicolon and the NULL
2544 dest[dest_index++] = ';';
2545 dest[dest_index] = '\0';
2546 return dest;
2547 }
2548
2549 // Used to obtain the package name from a fully qualified class name.
2550 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2551 if (name == NULL) {
2552 return NULL;
2553 } else {
2554 if (name->utf8_length() <= 0) {
2555 return NULL;
2556 }
2557 ResourceMark rm;
2558 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2559 if (package_name == NULL) {
2560 return NULL;
2561 }
2562 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2563 return pkg_name;
2564 }
2565 }
2566
2567 ModuleEntry* InstanceKlass::module() const {
2568 // For an unsafe anonymous class return the host class' module
2569 if (is_unsafe_anonymous()) {
2570 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2571 return unsafe_anonymous_host()->module();
2572 }
2573
2574 // Class is in a named package
2575 if (!in_unnamed_package()) {
2576 return _package_entry->module();
2577 }
2578
2579 // Class is in an unnamed package, return its loader's unnamed module
2580 return class_loader_data()->unnamed_module();
2581 }
2582
2583 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2584
2585 // ensure java/ packages only loaded by boot or platform builtin loaders
2586 check_prohibited_package(name(), loader_data, CHECK);
2587
2588 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2589
2590 if (pkg_name != NULL && loader_data != NULL) {
2591
2592 // Find in class loader's package entry table.
2593 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2594
2595 // If the package name is not found in the loader's package
2596 // entry table, it is an indication that the package has not
2597 // been defined. Consider it defined within the unnamed module.
2598 if (_package_entry == NULL) {
2599 ResourceMark rm;
2600
2601 if (!ModuleEntryTable::javabase_defined()) {
2602 // Before java.base is defined during bootstrapping, define all packages in
2603 // the java.base module. If a non-java.base package is erroneously placed
2604 // in the java.base module it will be caught later when java.base
2605 // is defined by ModuleEntryTable::verify_javabase_packages check.
2606 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2607 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2608 } else {
2609 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2610 _package_entry = loader_data->packages()->lookup(pkg_name,
2611 loader_data->unnamed_module());
2612 }
2613
2614 // A package should have been successfully created
2615 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2616 name()->as_C_string(), loader_data->loader_name_and_id());
2617 }
2618
2619 if (log_is_enabled(Debug, module)) {
2620 ResourceMark rm;
2621 ModuleEntry* m = _package_entry->module();
2622 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2623 external_name(),
2624 pkg_name->as_C_string(),
2625 loader_data->loader_name_and_id(),
2626 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2627 }
2628 } else {
2629 ResourceMark rm;
2630 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2631 external_name(),
2632 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2633 UNNAMED_MODULE);
2634 }
2635 }
2636
2637
2638 // different versions of is_same_class_package
2639
2640 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2641 oop classloader1 = this->class_loader();
2642 PackageEntry* classpkg1 = this->package();
2643 if (class2->is_objArray_klass()) {
2644 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2645 }
2646
2647 oop classloader2;
2648 PackageEntry* classpkg2;
2649 if (class2->is_instance_klass()) {
2650 classloader2 = class2->class_loader();
2651 classpkg2 = class2->package();
2652 } else {
2653 assert(class2->is_typeArray_klass(), "should be type array");
2654 classloader2 = NULL;
2655 classpkg2 = NULL;
2656 }
2657
2658 // Same package is determined by comparing class loader
2659 // and package entries. Both must be the same. This rule
2660 // applies even to classes that are defined in the unnamed
2661 // package, they still must have the same class loader.
2662 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2663 return true;
2664 }
2665
2666 return false;
2667 }
2668
2669 // return true if this class and other_class are in the same package. Classloader
2670 // and classname information is enough to determine a class's package
2671 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2672 const Symbol* other_class_name) const {
2673 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2674 return false;
2675 }
2676 if (name()->fast_compare(other_class_name) == 0) {
2677 return true;
2678 }
2679
2680 {
2681 ResourceMark rm;
2682
2683 bool bad_class_name = false;
2684 const char* other_pkg =
2685 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2686 if (bad_class_name) {
2687 return false;
2688 }
2689 // Check that package_from_name() returns NULL, not "", if there is no package.
2690 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2691
2692 const Symbol* const this_package_name =
2693 this->package() != NULL ? this->package()->name() : NULL;
2694
2695 if (this_package_name == NULL || other_pkg == NULL) {
2696 // One of the two doesn't have a package. Only return true if the other
2697 // one also doesn't have a package.
2698 return (const char*)this_package_name == other_pkg;
2699 }
2700
2701 // Check if package is identical
2702 return this_package_name->equals(other_pkg);
2703 }
2704 }
2705
2706 // Returns true iff super_method can be overridden by a method in targetclassname
2707 // See JLS 3rd edition 8.4.6.1
2708 // Assumes name-signature match
2709 // "this" is InstanceKlass of super_method which must exist
2710 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2711 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2712 // Private methods can not be overridden
2713 if (super_method->is_private()) {
2714 return false;
2715 }
2716 // If super method is accessible, then override
2717 if ((super_method->is_protected()) ||
2718 (super_method->is_public())) {
2719 return true;
2720 }
2721 // Package-private methods are not inherited outside of package
2722 assert(super_method->is_package_private(), "must be package private");
2723 return(is_same_class_package(targetclassloader(), targetclassname));
2724 }
2725
2726 // Only boot and platform class loaders can define classes in "java/" packages.
2727 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2728 ClassLoaderData* loader_data,
2729 TRAPS) {
2730 if (!loader_data->is_boot_class_loader_data() &&
2731 !loader_data->is_platform_class_loader_data() &&
2732 class_name != NULL) {
2733 ResourceMark rm(THREAD);
2734 char* name = class_name->as_C_string();
2735 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2736 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2737 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2738 name = pkg_name->as_C_string();
2739 const char* class_loader_name = loader_data->loader_name_and_id();
2740 StringUtils::replace_no_expand(name, "/", ".");
2741 const char* msg_text1 = "Class loader (instance of): ";
2742 const char* msg_text2 = " tried to load prohibited package name: ";
2743 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2744 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2745 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2746 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2747 }
2748 }
2749 return;
2750 }
2751
2752 // tell if two classes have the same enclosing class (at package level)
2753 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2754 if (class2 == this) return true;
2755 if (!class2->is_instance_klass()) return false;
2756
2757 // must be in same package before we try anything else
2758 if (!is_same_class_package(class2))
2759 return false;
2760
2761 // As long as there is an outer_this.getEnclosingClass,
2762 // shift the search outward.
2763 const InstanceKlass* outer_this = this;
2764 for (;;) {
2765 // As we walk along, look for equalities between outer_this and class2.
2766 // Eventually, the walks will terminate as outer_this stops
2767 // at the top-level class around the original class.
2768 bool ignore_inner_is_member;
2769 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2770 CHECK_false);
2771 if (next == NULL) break;
2772 if (next == class2) return true;
2773 outer_this = InstanceKlass::cast(next);
2774 }
2775
2776 // Now do the same for class2.
2777 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2778 for (;;) {
2779 bool ignore_inner_is_member;
2780 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2781 CHECK_false);
2782 if (next == NULL) break;
2783 // Might as well check the new outer against all available values.
2784 if (next == this) return true;
2785 if (next == outer_this) return true;
2786 outer2 = InstanceKlass::cast(next);
2787 }
2788
2789 // If by this point we have not found an equality between the
2790 // two classes, we know they are in separate package members.
2791 return false;
2792 }
2793
2794 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2795 constantPoolHandle i_cp(THREAD, constants());
2796 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2797 int ioff = iter.inner_class_info_index();
2798 if (ioff != 0) {
2799 // Check to see if the name matches the class we're looking for
2800 // before attempting to find the class.
2801 if (i_cp->klass_name_at_matches(this, ioff)) {
2802 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2803 if (this == inner_klass) {
2804 *ooff = iter.outer_class_info_index();
2805 *noff = iter.inner_name_index();
2806 return true;
2807 }
2808 }
2809 }
2810 }
2811 return false;
2812 }
2813
2814 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2815 InstanceKlass* outer_klass = NULL;
2816 *inner_is_member = false;
2817 int ooff = 0, noff = 0;
2818 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2819 if (has_inner_classes_attr) {
2820 constantPoolHandle i_cp(THREAD, constants());
2821 if (ooff != 0) {
2822 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2823 outer_klass = InstanceKlass::cast(ok);
2824 *inner_is_member = true;
2825 }
2826 if (NULL == outer_klass) {
2827 // It may be unsafe anonymous; try for that.
2828 int encl_method_class_idx = enclosing_method_class_index();
2829 if (encl_method_class_idx != 0) {
2830 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2831 outer_klass = InstanceKlass::cast(ok);
2832 *inner_is_member = false;
2833 }
2834 }
2835 }
2836
2837 // If no inner class attribute found for this class.
2838 if (NULL == outer_klass) return NULL;
2839
2840 // Throws an exception if outer klass has not declared k as an inner klass
2841 // We need evidence that each klass knows about the other, or else
2842 // the system could allow a spoof of an inner class to gain access rights.
2843 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2844 return outer_klass;
2845 }
2846
2847 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2848 jint access = access_flags().as_int();
2849
2850 // But check if it happens to be member class.
2851 InnerClassesIterator iter(this);
2852 for (; !iter.done(); iter.next()) {
2853 int ioff = iter.inner_class_info_index();
2854 // Inner class attribute can be zero, skip it.
2855 // Strange but true: JVM spec. allows null inner class refs.
2856 if (ioff == 0) continue;
2857
2858 // only look at classes that are already loaded
2859 // since we are looking for the flags for our self.
2860 Symbol* inner_name = constants()->klass_name_at(ioff);
2861 if (name() == inner_name) {
2862 // This is really a member class.
2863 access = iter.inner_access_flags();
2864 break;
2865 }
2866 }
2867 // Remember to strip ACC_SUPER bit
2868 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2869 }
2870
2871 jint InstanceKlass::jvmti_class_status() const {
2872 jint result = 0;
2873
2874 if (is_linked()) {
2875 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2876 }
2877
2878 if (is_initialized()) {
2879 assert(is_linked(), "Class status is not consistent");
2880 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2881 }
2882 if (is_in_error_state()) {
2883 result |= JVMTI_CLASS_STATUS_ERROR;
2884 }
2885 return result;
2886 }
2887
2888 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2889 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2890 int method_table_offset_in_words = ioe->offset()/wordSize;
2891 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2892 / itableOffsetEntry::size();
2893
2894 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2895 // If the interface isn't implemented by the receiver class,
2896 // the VM should throw IncompatibleClassChangeError.
2897 if (cnt >= nof_interfaces) {
2898 ResourceMark rm(THREAD);
2899 stringStream ss;
2900 bool same_module = (module() == holder->module());
2901 ss.print("Receiver class %s does not implement "
2902 "the interface %s defining the method to be called "
2903 "(%s%s%s)",
2904 external_name(), holder->external_name(),
2905 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2906 (same_module) ? "" : "; ",
2907 (same_module) ? "" : holder->class_in_module_of_loader());
2908 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2909 }
2910
2911 Klass* ik = ioe->interface_klass();
2912 if (ik == holder) break;
2913 }
2914
2915 itableMethodEntry* ime = ioe->first_method_entry(this);
2916 Method* m = ime[index].method();
2917 if (m == NULL) {
2918 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2919 }
2920 return m;
2921 }
2922
2923
2924 #if INCLUDE_JVMTI
2925 // update default_methods for redefineclasses for methods that are
2926 // not yet in the vtable due to concurrent subclass define and superinterface
2927 // redefinition
2928 // Note: those in the vtable, should have been updated via adjust_method_entries
2929 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2930 // search the default_methods for uses of either obsolete or EMCP methods
2931 if (default_methods() != NULL) {
2932 for (int index = 0; index < default_methods()->length(); index ++) {
2933 Method* old_method = default_methods()->at(index);
2934 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2935 continue; // skip uninteresting entries
2936 }
2937 assert(!old_method->is_deleted(), "default methods may not be deleted");
2938
2939 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2940
2941 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2942 assert(old_method != new_method, "sanity check");
2943
2944 default_methods()->at_put(index, new_method);
2945 if (log_is_enabled(Info, redefine, class, update)) {
2946 ResourceMark rm;
2947 if (!(*trace_name_printed)) {
2948 log_info(redefine, class, update)
2949 ("adjust: klassname=%s default methods from name=%s",
2950 external_name(), old_method->method_holder()->external_name());
2951 *trace_name_printed = true;
2952 }
2953 log_debug(redefine, class, update, vtables)
2954 ("default method update: %s(%s) ",
2955 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2956 }
2957 }
2958 }
2959 }
2960 #endif // INCLUDE_JVMTI
2961
2962 // On-stack replacement stuff
2963 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2964 // only one compilation can be active
2965 {
2966 // This is a short non-blocking critical region, so the no safepoint check is ok.
2967 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2968 assert(n->is_osr_method(), "wrong kind of nmethod");
2969 n->set_osr_link(osr_nmethods_head());
2970 set_osr_nmethods_head(n);
2971 // Raise the highest osr level if necessary
2972 if (TieredCompilation) {
2973 Method* m = n->method();
2974 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2975 }
2976 }
2977
2978 // Get rid of the osr methods for the same bci that have lower levels.
2979 if (TieredCompilation) {
2980 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2981 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2982 if (inv != NULL && inv->is_in_use()) {
2983 inv->make_not_entrant();
2984 }
2985 }
2986 }
2987 }
2988
2989 // Remove osr nmethod from the list. Return true if found and removed.
2990 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2991 // This is a short non-blocking critical region, so the no safepoint check is ok.
2992 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2993 assert(n->is_osr_method(), "wrong kind of nmethod");
2994 nmethod* last = NULL;
2995 nmethod* cur = osr_nmethods_head();
2996 int max_level = CompLevel_none; // Find the max comp level excluding n
2997 Method* m = n->method();
2998 // Search for match
2999 bool found = false;
3000 while(cur != NULL && cur != n) {
3001 if (TieredCompilation && m == cur->method()) {
3002 // Find max level before n
3003 max_level = MAX2(max_level, cur->comp_level());
3004 }
3005 last = cur;
3006 cur = cur->osr_link();
3007 }
3008 nmethod* next = NULL;
3009 if (cur == n) {
3010 found = true;
3011 next = cur->osr_link();
3012 if (last == NULL) {
3013 // Remove first element
3014 set_osr_nmethods_head(next);
3015 } else {
3016 last->set_osr_link(next);
3017 }
3018 }
3019 n->set_osr_link(NULL);
3020 if (TieredCompilation) {
3021 cur = next;
3022 while (cur != NULL) {
3023 // Find max level after n
3024 if (m == cur->method()) {
3025 max_level = MAX2(max_level, cur->comp_level());
3026 }
3027 cur = cur->osr_link();
3028 }
3029 m->set_highest_osr_comp_level(max_level);
3030 }
3031 return found;
3032 }
3033
3034 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3035 // This is a short non-blocking critical region, so the no safepoint check is ok.
3036 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3037 nmethod* osr = osr_nmethods_head();
3038 int found = 0;
3039 while (osr != NULL) {
3040 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3041 if (osr->method() == m) {
3042 osr->mark_for_deoptimization();
3043 found++;
3044 }
3045 osr = osr->osr_link();
3046 }
3047 return found;
3048 }
3049
3050 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3051 // This is a short non-blocking critical region, so the no safepoint check is ok.
3052 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3053 nmethod* osr = osr_nmethods_head();
3054 nmethod* best = NULL;
3055 while (osr != NULL) {
3056 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3057 // There can be a time when a c1 osr method exists but we are waiting
3058 // for a c2 version. When c2 completes its osr nmethod we will trash
3059 // the c1 version and only be able to find the c2 version. However
3060 // while we overflow in the c1 code at back branches we don't want to
3061 // try and switch to the same code as we are already running
3062
3063 if (osr->method() == m &&
3064 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3065 if (match_level) {
3066 if (osr->comp_level() == comp_level) {
3067 // Found a match - return it.
3068 return osr;
3069 }
3070 } else {
3071 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3072 if (osr->comp_level() == CompLevel_highest_tier) {
3073 // Found the best possible - return it.
3074 return osr;
3075 }
3076 best = osr;
3077 }
3078 }
3079 }
3080 osr = osr->osr_link();
3081 }
3082 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3083 return best;
3084 }
3085 return NULL;
3086 }
3087
3088 // -----------------------------------------------------------------------------------------------------
3089 // Printing
3090
3091 #ifndef PRODUCT
3092
3093 #define BULLET " - "
3094
3095 static const char* state_names[] = {
3096 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3097 };
3098
3099 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3100 for (int i = 0; i < len; i++) {
3101 intptr_t e = start[i];
3102 st->print("%d : " INTPTR_FORMAT, i, e);
3103 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3104 st->print(" ");
3105 ((Metadata*)e)->print_value_on(st);
3106 }
3107 st->cr();
3108 }
3109 }
3110
3111 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3112 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3113 }
3114
3115 void InstanceKlass::print_on(outputStream* st) const {
3116 assert(is_klass(), "must be klass");
3117 Klass::print_on(st);
3118
3119 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3120 st->print(BULLET"klass size: %d", size()); st->cr();
3121 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3122 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3123 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3124 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3125 st->print(BULLET"sub: ");
3126 Klass* sub = subklass();
3127 int n;
3128 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3129 if (n < MaxSubklassPrintSize) {
3130 sub->print_value_on(st);
3131 st->print(" ");
3132 }
3133 }
3134 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3135 st->cr();
3136
3137 if (is_interface()) {
3138 MutexLocker ml(Compile_lock);
3139 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3140 if (nof_implementors() == 1) {
3141 st->print_cr(BULLET"implementor: ");
3142 st->print(" ");
3143 implementor()->print_value_on(st);
3144 st->cr();
3145 }
3146 }
3147
3148 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3149 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3150 if (Verbose || WizardMode) {
3151 Array<Method*>* method_array = methods();
3152 for (int i = 0; i < method_array->length(); i++) {
3153 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3154 }
3155 }
3156 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3157 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3158 if (Verbose && default_methods() != NULL) {
3159 Array<Method*>* method_array = default_methods();
3160 for (int i = 0; i < method_array->length(); i++) {
3161 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3162 }
3163 }
3164 if (default_vtable_indices() != NULL) {
3165 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3166 }
3167 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3168 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3169 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3170 if (class_loader_data() != NULL) {
3171 st->print(BULLET"class loader data: ");
3172 class_loader_data()->print_value_on(st);
3173 st->cr();
3174 }
3175 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3176 if (source_file_name() != NULL) {
3177 st->print(BULLET"source file: ");
3178 source_file_name()->print_value_on(st);
3179 st->cr();
3180 }
3181 if (source_debug_extension() != NULL) {
3182 st->print(BULLET"source debug extension: ");
3183 st->print("%s", source_debug_extension());
3184 st->cr();
3185 }
3186 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3187 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3188 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3189 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3190 {
3191 bool have_pv = false;
3192 // previous versions are linked together through the InstanceKlass
3193 for (InstanceKlass* pv_node = previous_versions();
3194 pv_node != NULL;
3195 pv_node = pv_node->previous_versions()) {
3196 if (!have_pv)
3197 st->print(BULLET"previous version: ");
3198 have_pv = true;
3199 pv_node->constants()->print_value_on(st);
3200 }
3201 if (have_pv) st->cr();
3202 }
3203
3204 if (generic_signature() != NULL) {
3205 st->print(BULLET"generic signature: ");
3206 generic_signature()->print_value_on(st);
3207 st->cr();
3208 }
3209 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3210 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3211 if (java_mirror() != NULL) {
3212 st->print(BULLET"java mirror: ");
3213 java_mirror()->print_value_on(st);
3214 st->cr();
3215 } else {
3216 st->print_cr(BULLET"java mirror: NULL");
3217 }
3218 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3219 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3220 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3221 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3222 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3223 FieldPrinter print_static_field(st);
3224 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3225 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3226 FieldPrinter print_nonstatic_field(st);
3227 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3228 ik->do_nonstatic_fields(&print_nonstatic_field);
3229
3230 st->print(BULLET"non-static oop maps: ");
3231 OopMapBlock* map = start_of_nonstatic_oop_maps();
3232 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3233 while (map < end_map) {
3234 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3235 map++;
3236 }
3237 st->cr();
3238 }
3239
3240 #endif //PRODUCT
3241
3242 void InstanceKlass::print_value_on(outputStream* st) const {
3243 assert(is_klass(), "must be klass");
3244 if (Verbose || WizardMode) access_flags().print_on(st);
3245 name()->print_value_on(st);
3246 }
3247
3248 #ifndef PRODUCT
3249
3250 void FieldPrinter::do_field(fieldDescriptor* fd) {
3251 _st->print(BULLET);
3252 if (_obj == NULL) {
3253 fd->print_on(_st);
3254 _st->cr();
3255 } else {
3256 fd->print_on_for(_st, _obj);
3257 _st->cr();
3258 }
3259 }
3260
3261
3262 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3263 Klass::oop_print_on(obj, st);
3264
3265 if (this == SystemDictionary::String_klass()) {
3266 typeArrayOop value = java_lang_String::value(obj);
3267 juint length = java_lang_String::length(obj);
3268 if (value != NULL &&
3269 value->is_typeArray() &&
3270 length <= (juint) value->length()) {
3271 st->print(BULLET"string: ");
3272 java_lang_String::print(obj, st);
3273 st->cr();
3274 if (!WizardMode) return; // that is enough
3275 }
3276 }
3277
3278 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3279 FieldPrinter print_field(st, obj);
3280 do_nonstatic_fields(&print_field);
3281
3282 if (this == SystemDictionary::Class_klass()) {
3283 st->print(BULLET"signature: ");
3284 java_lang_Class::print_signature(obj, st);
3285 st->cr();
3286 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3287 st->print(BULLET"fake entry for mirror: ");
3288 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3289 st->cr();
3290 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3291 st->print(BULLET"fake entry for array: ");
3292 Metadata::print_value_on_maybe_null(st, array_klass);
3293 st->cr();
3294 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3295 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3296 Klass* real_klass = java_lang_Class::as_Klass(obj);
3297 if (real_klass != NULL && real_klass->is_instance_klass()) {
3298 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3299 }
3300 } else if (this == SystemDictionary::MethodType_klass()) {
3301 st->print(BULLET"signature: ");
3302 java_lang_invoke_MethodType::print_signature(obj, st);
3303 st->cr();
3304 }
3305 }
3306
3307 bool InstanceKlass::verify_itable_index(int i) {
3308 int method_count = klassItable::method_count_for_interface(this);
3309 assert(i >= 0 && i < method_count, "index out of bounds");
3310 return true;
3311 }
3312
3313 #endif //PRODUCT
3314
3315 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3316 st->print("a ");
3317 name()->print_value_on(st);
3318 obj->print_address_on(st);
3319 if (this == SystemDictionary::String_klass()
3320 && java_lang_String::value(obj) != NULL) {
3321 ResourceMark rm;
3322 int len = java_lang_String::length(obj);
3323 int plen = (len < 24 ? len : 12);
3324 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3325 st->print(" = \"%s\"", str);
3326 if (len > plen)
3327 st->print("...[%d]", len);
3328 } else if (this == SystemDictionary::Class_klass()) {
3329 Klass* k = java_lang_Class::as_Klass(obj);
3330 st->print(" = ");
3331 if (k != NULL) {
3332 k->print_value_on(st);
3333 } else {
3334 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3335 st->print("%s", tname ? tname : "type?");
3336 }
3337 } else if (this == SystemDictionary::MethodType_klass()) {
3338 st->print(" = ");
3339 java_lang_invoke_MethodType::print_signature(obj, st);
3340 } else if (java_lang_boxing_object::is_instance(obj)) {
3341 st->print(" = ");
3342 java_lang_boxing_object::print(obj, st);
3343 } else if (this == SystemDictionary::LambdaForm_klass()) {
3344 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3345 if (vmentry != NULL) {
3346 st->print(" => ");
3347 vmentry->print_value_on(st);
3348 }
3349 } else if (this == SystemDictionary::MemberName_klass()) {
3350 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3351 if (vmtarget != NULL) {
3352 st->print(" = ");
3353 vmtarget->print_value_on(st);
3354 } else {
3355 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3356 st->print(".");
3357 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3358 }
3359 }
3360 }
3361
3362 const char* InstanceKlass::internal_name() const {
3363 return external_name();
3364 }
3365
3366 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3367 const char* module_name,
3368 const ClassFileStream* cfs) const {
3369 if (!log_is_enabled(Info, class, load)) {
3370 return;
3371 }
3372
3373 ResourceMark rm;
3374 LogMessage(class, load) msg;
3375 stringStream info_stream;
3376
3377 // Name and class hierarchy info
3378 info_stream.print("%s", external_name());
3379
3380 // Source
3381 if (cfs != NULL) {
3382 if (cfs->source() != NULL) {
3383 if (module_name != NULL) {
3384 if (ClassLoader::is_modules_image(cfs->source())) {
3385 info_stream.print(" source: jrt:/%s", module_name);
3386 } else {
3387 info_stream.print(" source: %s", cfs->source());
3388 }
3389 } else {
3390 info_stream.print(" source: %s", cfs->source());
3391 }
3392 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3393 Thread* THREAD = Thread::current();
3394 Klass* caller =
3395 THREAD->is_Java_thread()
3396 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3397 : NULL;
3398 // caller can be NULL, for example, during a JVMTI VM_Init hook
3399 if (caller != NULL) {
3400 info_stream.print(" source: instance of %s", caller->external_name());
3401 } else {
3402 // source is unknown
3403 }
3404 } else {
3405 oop class_loader = loader_data->class_loader();
3406 info_stream.print(" source: %s", class_loader->klass()->external_name());
3407 }
3408 } else {
3409 info_stream.print(" source: shared objects file");
3410 }
3411
3412 msg.info("%s", info_stream.as_string());
3413
3414 if (log_is_enabled(Debug, class, load)) {
3415 stringStream debug_stream;
3416
3417 // Class hierarchy info
3418 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3419 p2i(this), p2i(superklass()));
3420
3421 // Interfaces
3422 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3423 debug_stream.print(" interfaces:");
3424 int length = local_interfaces()->length();
3425 for (int i = 0; i < length; i++) {
3426 debug_stream.print(" " INTPTR_FORMAT,
3427 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3428 }
3429 }
3430
3431 // Class loader
3432 debug_stream.print(" loader: [");
3433 loader_data->print_value_on(&debug_stream);
3434 debug_stream.print("]");
3435
3436 // Classfile checksum
3437 if (cfs) {
3438 debug_stream.print(" bytes: %d checksum: %08x",
3439 cfs->length(),
3440 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3441 cfs->length()));
3442 }
3443
3444 msg.debug("%s", debug_stream.as_string());
3445 }
3446 }
3447
3448 #if INCLUDE_SERVICES
3449 // Size Statistics
3450 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3451 Klass::collect_statistics(sz);
3452
3453 sz->_inst_size = wordSize * size_helper();
3454 sz->_vtab_bytes = wordSize * vtable_length();
3455 sz->_itab_bytes = wordSize * itable_length();
3456 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3457
3458 int n = 0;
3459 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3460 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3461 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3462 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3463 n += (sz->_fields_bytes = sz->count_array(fields()));
3464 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3465 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3466 sz->_ro_bytes += n;
3467
3468 const ConstantPool* cp = constants();
3469 if (cp) {
3470 cp->collect_statistics(sz);
3471 }
3472
3473 const Annotations* anno = annotations();
3474 if (anno) {
3475 anno->collect_statistics(sz);
3476 }
3477
3478 const Array<Method*>* methods_array = methods();
3479 if (methods()) {
3480 for (int i = 0; i < methods_array->length(); i++) {
3481 Method* method = methods_array->at(i);
3482 if (method) {
3483 sz->_method_count ++;
3484 method->collect_statistics(sz);
3485 }
3486 }
3487 }
3488 }
3489 #endif // INCLUDE_SERVICES
3490
3491 // Verification
3492
3493 class VerifyFieldClosure: public BasicOopIterateClosure {
3494 protected:
3495 template <class T> void do_oop_work(T* p) {
3496 oop obj = RawAccess<>::oop_load(p);
3497 if (!oopDesc::is_oop_or_null(obj)) {
3498 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3499 Universe::print_on(tty);
3500 guarantee(false, "boom");
3501 }
3502 }
3503 public:
3504 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3505 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3506 };
3507
3508 void InstanceKlass::verify_on(outputStream* st) {
3509 #ifndef PRODUCT
3510 // Avoid redundant verifies, this really should be in product.
3511 if (_verify_count == Universe::verify_count()) return;
3512 _verify_count = Universe::verify_count();
3513 #endif
3514
3515 // Verify Klass
3516 Klass::verify_on(st);
3517
3518 // Verify that klass is present in ClassLoaderData
3519 guarantee(class_loader_data()->contains_klass(this),
3520 "this class isn't found in class loader data");
3521
3522 // Verify vtables
3523 if (is_linked()) {
3524 // $$$ This used to be done only for m/s collections. Doing it
3525 // always seemed a valid generalization. (DLD -- 6/00)
3526 vtable().verify(st);
3527 }
3528
3529 // Verify first subklass
3530 if (subklass() != NULL) {
3531 guarantee(subklass()->is_klass(), "should be klass");
3532 }
3533
3534 // Verify siblings
3535 Klass* super = this->super();
3536 Klass* sib = next_sibling();
3537 if (sib != NULL) {
3538 if (sib == this) {
3539 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3540 }
3541
3542 guarantee(sib->is_klass(), "should be klass");
3543 guarantee(sib->super() == super, "siblings should have same superklass");
3544 }
3545
3546 // Verify implementor fields requires the Compile_lock, but this is sometimes
3547 // called inside a safepoint, so don't verify.
3548
3549 // Verify local interfaces
3550 if (local_interfaces()) {
3551 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3552 for (int j = 0; j < local_interfaces->length(); j++) {
3553 InstanceKlass* e = local_interfaces->at(j);
3554 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3555 }
3556 }
3557
3558 // Verify transitive interfaces
3559 if (transitive_interfaces() != NULL) {
3560 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3561 for (int j = 0; j < transitive_interfaces->length(); j++) {
3562 InstanceKlass* e = transitive_interfaces->at(j);
3563 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3564 }
3565 }
3566
3567 // Verify methods
3568 if (methods() != NULL) {
3569 Array<Method*>* methods = this->methods();
3570 for (int j = 0; j < methods->length(); j++) {
3571 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3572 }
3573 for (int j = 0; j < methods->length() - 1; j++) {
3574 Method* m1 = methods->at(j);
3575 Method* m2 = methods->at(j + 1);
3576 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3577 }
3578 }
3579
3580 // Verify method ordering
3581 if (method_ordering() != NULL) {
3582 Array<int>* method_ordering = this->method_ordering();
3583 int length = method_ordering->length();
3584 if (JvmtiExport::can_maintain_original_method_order() ||
3585 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3586 guarantee(length == methods()->length(), "invalid method ordering length");
3587 jlong sum = 0;
3588 for (int j = 0; j < length; j++) {
3589 int original_index = method_ordering->at(j);
3590 guarantee(original_index >= 0, "invalid method ordering index");
3591 guarantee(original_index < length, "invalid method ordering index");
3592 sum += original_index;
3593 }
3594 // Verify sum of indices 0,1,...,length-1
3595 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3596 } else {
3597 guarantee(length == 0, "invalid method ordering length");
3598 }
3599 }
3600
3601 // Verify default methods
3602 if (default_methods() != NULL) {
3603 Array<Method*>* methods = this->default_methods();
3604 for (int j = 0; j < methods->length(); j++) {
3605 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3606 }
3607 for (int j = 0; j < methods->length() - 1; j++) {
3608 Method* m1 = methods->at(j);
3609 Method* m2 = methods->at(j + 1);
3610 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3611 }
3612 }
3613
3614 // Verify JNI static field identifiers
3615 if (jni_ids() != NULL) {
3616 jni_ids()->verify(this);
3617 }
3618
3619 // Verify other fields
3620 if (array_klasses() != NULL) {
3621 guarantee(array_klasses()->is_klass(), "should be klass");
3622 }
3623 if (constants() != NULL) {
3624 guarantee(constants()->is_constantPool(), "should be constant pool");
3625 }
3626 const Klass* anonymous_host = unsafe_anonymous_host();
3627 if (anonymous_host != NULL) {
3628 guarantee(anonymous_host->is_klass(), "should be klass");
3629 }
3630 }
3631
3632 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3633 Klass::oop_verify_on(obj, st);
3634 VerifyFieldClosure blk;
3635 obj->oop_iterate(&blk);
3636 }
3637
3638
3639 // JNIid class for jfieldIDs only
3640 // Note to reviewers:
3641 // These JNI functions are just moved over to column 1 and not changed
3642 // in the compressed oops workspace.
3643 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3644 _holder = holder;
3645 _offset = offset;
3646 _next = next;
3647 debug_only(_is_static_field_id = false;)
3648 }
3649
3650
3651 JNIid* JNIid::find(int offset) {
3652 JNIid* current = this;
3653 while (current != NULL) {
3654 if (current->offset() == offset) return current;
3655 current = current->next();
3656 }
3657 return NULL;
3658 }
3659
3660 void JNIid::deallocate(JNIid* current) {
3661 while (current != NULL) {
3662 JNIid* next = current->next();
3663 delete current;
3664 current = next;
3665 }
3666 }
3667
3668
3669 void JNIid::verify(Klass* holder) {
3670 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3671 int end_field_offset;
3672 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3673
3674 JNIid* current = this;
3675 while (current != NULL) {
3676 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3677 #ifdef ASSERT
3678 int o = current->offset();
3679 if (current->is_static_field_id()) {
3680 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3681 }
3682 #endif
3683 current = current->next();
3684 }
3685 }
3686
3687 #ifdef ASSERT
3688 void InstanceKlass::set_init_state(ClassState state) {
3689 bool good_state = is_shared() ? (_init_state <= state)
3690 : (_init_state < state);
3691 assert(good_state || state == allocated, "illegal state transition");
3692 _init_state = (u1)state;
3693 }
3694 #endif
3695
3696 #if INCLUDE_JVMTI
3697
3698 // RedefineClasses() support for previous versions
3699
3700 // Globally, there is at least one previous version of a class to walk
3701 // during class unloading, which is saved because old methods in the class
3702 // are still running. Otherwise the previous version list is cleaned up.
3703 bool InstanceKlass::_has_previous_versions = false;
3704
3705 // Returns true if there are previous versions of a class for class
3706 // unloading only. Also resets the flag to false. purge_previous_version
3707 // will set the flag to true if there are any left, i.e., if there's any
3708 // work to do for next time. This is to avoid the expensive code cache
3709 // walk in CLDG::clean_deallocate_lists().
3710 bool InstanceKlass::has_previous_versions_and_reset() {
3711 bool ret = _has_previous_versions;
3712 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3713 ret ? "true" : "false");
3714 _has_previous_versions = false;
3715 return ret;
3716 }
3717
3718 // Purge previous versions before adding new previous versions of the class and
3719 // during class unloading.
3720 void InstanceKlass::purge_previous_version_list() {
3721 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3722 assert(has_been_redefined(), "Should only be called for main class");
3723
3724 // Quick exit.
3725 if (previous_versions() == NULL) {
3726 return;
3727 }
3728
3729 // This klass has previous versions so see what we can cleanup
3730 // while it is safe to do so.
3731
3732 int deleted_count = 0; // leave debugging breadcrumbs
3733 int live_count = 0;
3734 ClassLoaderData* loader_data = class_loader_data();
3735 assert(loader_data != NULL, "should never be null");
3736
3737 ResourceMark rm;
3738 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3739
3740 // previous versions are linked together through the InstanceKlass
3741 InstanceKlass* pv_node = previous_versions();
3742 InstanceKlass* last = this;
3743 int version = 0;
3744
3745 // check the previous versions list
3746 for (; pv_node != NULL; ) {
3747
3748 ConstantPool* pvcp = pv_node->constants();
3749 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3750
3751 if (!pvcp->on_stack()) {
3752 // If the constant pool isn't on stack, none of the methods
3753 // are executing. Unlink this previous_version.
3754 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3755 // so will be deallocated during the next phase of class unloading.
3756 log_trace(redefine, class, iklass, purge)
3757 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3758 // For debugging purposes.
3759 pv_node->set_is_scratch_class();
3760 // Unlink from previous version list.
3761 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3762 InstanceKlass* next = pv_node->previous_versions();
3763 pv_node->link_previous_versions(NULL); // point next to NULL
3764 last->link_previous_versions(next);
3765 // Add to the deallocate list after unlinking
3766 loader_data->add_to_deallocate_list(pv_node);
3767 pv_node = next;
3768 deleted_count++;
3769 version++;
3770 continue;
3771 } else {
3772 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3773 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3774 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3775 live_count++;
3776 // found a previous version for next time we do class unloading
3777 _has_previous_versions = true;
3778 }
3779
3780 // At least one method is live in this previous version.
3781 // Reset dead EMCP methods not to get breakpoints.
3782 // All methods are deallocated when all of the methods for this class are no
3783 // longer running.
3784 Array<Method*>* method_refs = pv_node->methods();
3785 if (method_refs != NULL) {
3786 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3787 for (int j = 0; j < method_refs->length(); j++) {
3788 Method* method = method_refs->at(j);
3789
3790 if (!method->on_stack()) {
3791 // no breakpoints for non-running methods
3792 if (method->is_running_emcp()) {
3793 method->set_running_emcp(false);
3794 }
3795 } else {
3796 assert (method->is_obsolete() || method->is_running_emcp(),
3797 "emcp method cannot run after emcp bit is cleared");
3798 log_trace(redefine, class, iklass, purge)
3799 ("purge: %s(%s): prev method @%d in version @%d is alive",
3800 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3801 }
3802 }
3803 }
3804 // next previous version
3805 last = pv_node;
3806 pv_node = pv_node->previous_versions();
3807 version++;
3808 }
3809 log_trace(redefine, class, iklass, purge)
3810 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3811 }
3812
3813 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3814 int emcp_method_count) {
3815 int obsolete_method_count = old_methods->length() - emcp_method_count;
3816
3817 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3818 _previous_versions != NULL) {
3819 // We have a mix of obsolete and EMCP methods so we have to
3820 // clear out any matching EMCP method entries the hard way.
3821 int local_count = 0;
3822 for (int i = 0; i < old_methods->length(); i++) {
3823 Method* old_method = old_methods->at(i);
3824 if (old_method->is_obsolete()) {
3825 // only obsolete methods are interesting
3826 Symbol* m_name = old_method->name();
3827 Symbol* m_signature = old_method->signature();
3828
3829 // previous versions are linked together through the InstanceKlass
3830 int j = 0;
3831 for (InstanceKlass* prev_version = _previous_versions;
3832 prev_version != NULL;
3833 prev_version = prev_version->previous_versions(), j++) {
3834
3835 Array<Method*>* method_refs = prev_version->methods();
3836 for (int k = 0; k < method_refs->length(); k++) {
3837 Method* method = method_refs->at(k);
3838
3839 if (!method->is_obsolete() &&
3840 method->name() == m_name &&
3841 method->signature() == m_signature) {
3842 // The current RedefineClasses() call has made all EMCP
3843 // versions of this method obsolete so mark it as obsolete
3844 log_trace(redefine, class, iklass, add)
3845 ("%s(%s): flush obsolete method @%d in version @%d",
3846 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3847
3848 method->set_is_obsolete();
3849 break;
3850 }
3851 }
3852
3853 // The previous loop may not find a matching EMCP method, but
3854 // that doesn't mean that we can optimize and not go any
3855 // further back in the PreviousVersion generations. The EMCP
3856 // method for this generation could have already been made obsolete,
3857 // but there still may be an older EMCP method that has not
3858 // been made obsolete.
3859 }
3860
3861 if (++local_count >= obsolete_method_count) {
3862 // no more obsolete methods so bail out now
3863 break;
3864 }
3865 }
3866 }
3867 }
3868 }
3869
3870 // Save the scratch_class as the previous version if any of the methods are running.
3871 // The previous_versions are used to set breakpoints in EMCP methods and they are
3872 // also used to clean MethodData links to redefined methods that are no longer running.
3873 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3874 int emcp_method_count) {
3875 assert(Thread::current()->is_VM_thread(),
3876 "only VMThread can add previous versions");
3877
3878 ResourceMark rm;
3879 log_trace(redefine, class, iklass, add)
3880 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3881
3882 // Clean out old previous versions for this class
3883 purge_previous_version_list();
3884
3885 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3886 // a previous redefinition may be made obsolete by this redefinition.
3887 Array<Method*>* old_methods = scratch_class->methods();
3888 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3889
3890 // If the constant pool for this previous version of the class
3891 // is not marked as being on the stack, then none of the methods
3892 // in this previous version of the class are on the stack so
3893 // we don't need to add this as a previous version.
3894 ConstantPool* cp_ref = scratch_class->constants();
3895 if (!cp_ref->on_stack()) {
3896 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3897 // For debugging purposes.
3898 scratch_class->set_is_scratch_class();
3899 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3900 return;
3901 }
3902
3903 if (emcp_method_count != 0) {
3904 // At least one method is still running, check for EMCP methods
3905 for (int i = 0; i < old_methods->length(); i++) {
3906 Method* old_method = old_methods->at(i);
3907 if (!old_method->is_obsolete() && old_method->on_stack()) {
3908 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3909 // we can add breakpoints for it.
3910
3911 // We set the method->on_stack bit during safepoints for class redefinition
3912 // and use this bit to set the is_running_emcp bit.
3913 // After the safepoint, the on_stack bit is cleared and the running emcp
3914 // method may exit. If so, we would set a breakpoint in a method that
3915 // is never reached, but this won't be noticeable to the programmer.
3916 old_method->set_running_emcp(true);
3917 log_trace(redefine, class, iklass, add)
3918 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3919 } else if (!old_method->is_obsolete()) {
3920 log_trace(redefine, class, iklass, add)
3921 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3922 }
3923 }
3924 }
3925
3926 // Add previous version if any methods are still running.
3927 // Set has_previous_version flag for processing during class unloading.
3928 _has_previous_versions = true;
3929 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3930 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3931 scratch_class->link_previous_versions(previous_versions());
3932 link_previous_versions(scratch_class);
3933 } // end add_previous_version()
3934
3935 #endif // INCLUDE_JVMTI
3936
3937 Method* InstanceKlass::method_with_idnum(int idnum) {
3938 Method* m = NULL;
3939 if (idnum < methods()->length()) {
3940 m = methods()->at(idnum);
3941 }
3942 if (m == NULL || m->method_idnum() != idnum) {
3943 for (int index = 0; index < methods()->length(); ++index) {
3944 m = methods()->at(index);
3945 if (m->method_idnum() == idnum) {
3946 return m;
3947 }
3948 }
3949 // None found, return null for the caller to handle.
3950 return NULL;
3951 }
3952 return m;
3953 }
3954
3955
3956 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3957 if (idnum >= methods()->length()) {
3958 return NULL;
3959 }
3960 Method* m = methods()->at(idnum);
3961 if (m != NULL && m->orig_method_idnum() == idnum) {
3962 return m;
3963 }
3964 // Obsolete method idnum does not match the original idnum
3965 for (int index = 0; index < methods()->length(); ++index) {
3966 m = methods()->at(index);
3967 if (m->orig_method_idnum() == idnum) {
3968 return m;
3969 }
3970 }
3971 // None found, return null for the caller to handle.
3972 return NULL;
3973 }
3974
3975
3976 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3977 InstanceKlass* holder = get_klass_version(version);
3978 if (holder == NULL) {
3979 return NULL; // The version of klass is gone, no method is found
3980 }
3981 Method* method = holder->method_with_orig_idnum(idnum);
3982 return method;
3983 }
3984
3985 #if INCLUDE_JVMTI
3986 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3987 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3988 // Ignore the archived class stream data
3989 return NULL;
3990 } else {
3991 return _cached_class_file;
3992 }
3993 }
3994
3995 jint InstanceKlass::get_cached_class_file_len() {
3996 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3997 }
3998
3999 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4000 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4001 }
4002
4003 #if INCLUDE_CDS
4004 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
4005 if (DumpSharedSpaces) {
4006 return _cached_class_file;
4007 } else {
4008 assert(this->is_shared(), "class should be shared");
4009 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
4010 return _cached_class_file;
4011 } else {
4012 return NULL;
4013 }
4014 }
4015 }
4016 #endif
4017 #endif