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