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 if (length < 0) {
1205 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1206 }
1207 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1208 report_java_out_of_memory("Requested array size exceeds VM limit");
1209 JvmtiExport::post_array_size_exhausted();
1210 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1211 }
1212 int size = objArrayOopDesc::object_size(length);
1213 Klass* ak = array_klass(n, CHECK_NULL);
1214 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1215 /* do_zero */ true, CHECK_NULL);
1216 return o;
1217 }
1218
1219 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1220 if (TraceFinalizerRegistration) {
1221 tty->print("Registered ");
1222 i->print_value_on(tty);
1223 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1224 }
1225 instanceHandle h_i(THREAD, i);
1226 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1227 JavaValue result(T_VOID);
1228 JavaCallArguments args(h_i);
1229 methodHandle mh (THREAD, Universe::finalizer_register_method());
1230 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1231 return h_i();
1232 }
1233
1234 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1235 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1236 int size = size_helper(); // Query before forming handle.
1237
1238 instanceOop i;
1239
1240 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1241 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1242 i = register_finalizer(i, CHECK_NULL);
1243 }
1244 return i;
1245 }
1246
1247 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1248 return instanceHandle(THREAD, allocate_instance(THREAD));
1249 }
1250
1251 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1252 if (is_interface() || is_abstract()) {
1253 ResourceMark rm(THREAD);
1254 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1255 : vmSymbols::java_lang_InstantiationException(), external_name());
1256 }
1257 if (this == SystemDictionary::Class_klass()) {
1258 ResourceMark rm(THREAD);
1259 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1260 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1261 }
1262 }
1263
1264 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1265 // Need load-acquire for lock-free read
1266 if (array_klasses_acquire() == NULL) {
1267 if (or_null) return NULL;
1268
1269 ResourceMark rm;
1270 JavaThread *jt = (JavaThread *)THREAD;
1271 {
1272 // Atomic creation of array_klasses
1273 MutexLocker mc(Compile_lock, THREAD); // for vtables
1274 MutexLocker ma(MultiArray_lock, THREAD);
1275
1276 // Check if update has already taken place
1277 if (array_klasses() == NULL) {
1278 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1279 // use 'release' to pair with lock-free load
1280 release_set_array_klasses(k);
1281 }
1282 }
1283 }
1284 // _this will always be set at this point
1285 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1286 if (or_null) {
1287 return oak->array_klass_or_null(n);
1288 }
1289 return oak->array_klass(n, THREAD);
1290 }
1291
1292 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1293 return array_klass_impl(or_null, 1, THREAD);
1294 }
1295
1296 static int call_class_initializer_counter = 0; // for debugging
1297
1298 Method* InstanceKlass::class_initializer() const {
1299 Method* clinit = find_method(
1300 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1301 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1302 return clinit;
1303 }
1304 return NULL;
1305 }
1306
1307 void InstanceKlass::call_class_initializer(TRAPS) {
1308 if (ReplayCompiles &&
1309 (ReplaySuppressInitializers == 1 ||
1310 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1311 // Hide the existence of the initializer for the purpose of replaying the compile
1312 return;
1313 }
1314
1315 methodHandle h_method(THREAD, class_initializer());
1316 assert(!is_initialized(), "we cannot initialize twice");
1317 LogTarget(Info, class, init) lt;
1318 if (lt.is_enabled()) {
1319 ResourceMark rm;
1320 LogStream ls(lt);
1321 ls.print("%d Initializing ", call_class_initializer_counter++);
1322 name()->print_value_on(&ls);
1323 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1324 }
1325 if (h_method() != NULL) {
1326 JavaCallArguments args; // No arguments
1327 JavaValue result(T_VOID);
1328 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1329 }
1330 }
1331
1332
1333 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1334 InterpreterOopMap* entry_for) {
1335 // Lazily create the _oop_map_cache at first request
1336 // Lock-free access requires load_acquire.
1337 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1338 if (oop_map_cache == NULL) {
1339 MutexLocker x(OopMapCacheAlloc_lock);
1340 // Check if _oop_map_cache was allocated while we were waiting for this lock
1341 if ((oop_map_cache = _oop_map_cache) == NULL) {
1342 oop_map_cache = new OopMapCache();
1343 // Ensure _oop_map_cache is stable, since it is examined without a lock
1344 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1345 }
1346 }
1347 // _oop_map_cache is constant after init; lookup below does its own locking.
1348 oop_map_cache->lookup(method, bci, entry_for);
1349 }
1350
1351
1352 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1353 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1354 Symbol* f_name = fs.name();
1355 Symbol* f_sig = fs.signature();
1356 if (f_name == name && f_sig == sig) {
1357 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1358 return true;
1359 }
1360 }
1361 return false;
1362 }
1363
1364
1365 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1366 const int n = local_interfaces()->length();
1367 for (int i = 0; i < n; i++) {
1368 Klass* intf1 = local_interfaces()->at(i);
1369 assert(intf1->is_interface(), "just checking type");
1370 // search for field in current interface
1371 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1372 assert(fd->is_static(), "interface field must be static");
1373 return intf1;
1374 }
1375 // search for field in direct superinterfaces
1376 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1377 if (intf2 != NULL) return intf2;
1378 }
1379 // otherwise field lookup fails
1380 return NULL;
1381 }
1382
1383
1384 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1385 // search order according to newest JVM spec (5.4.3.2, p.167).
1386 // 1) search for field in current klass
1387 if (find_local_field(name, sig, fd)) {
1388 return const_cast<InstanceKlass*>(this);
1389 }
1390 // 2) search for field recursively in direct superinterfaces
1391 { Klass* intf = find_interface_field(name, sig, fd);
1392 if (intf != NULL) return intf;
1393 }
1394 // 3) apply field lookup recursively if superclass exists
1395 { Klass* supr = super();
1396 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1397 }
1398 // 4) otherwise field lookup fails
1399 return NULL;
1400 }
1401
1402
1403 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1404 // search order according to newest JVM spec (5.4.3.2, p.167).
1405 // 1) search for field in current klass
1406 if (find_local_field(name, sig, fd)) {
1407 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1408 }
1409 // 2) search for field recursively in direct superinterfaces
1410 if (is_static) {
1411 Klass* intf = find_interface_field(name, sig, fd);
1412 if (intf != NULL) return intf;
1413 }
1414 // 3) apply field lookup recursively if superclass exists
1415 { Klass* supr = super();
1416 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1417 }
1418 // 4) otherwise field lookup fails
1419 return NULL;
1420 }
1421
1422
1423 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1424 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1425 if (fs.offset() == offset) {
1426 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1427 if (fd->is_static() == is_static) return true;
1428 }
1429 }
1430 return false;
1431 }
1432
1433
1434 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1435 Klass* klass = const_cast<InstanceKlass*>(this);
1436 while (klass != NULL) {
1437 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1438 return true;
1439 }
1440 klass = klass->super();
1441 }
1442 return false;
1443 }
1444
1445
1446 void InstanceKlass::methods_do(void f(Method* method)) {
1447 // Methods aren't stable until they are loaded. This can be read outside
1448 // a lock through the ClassLoaderData for profiling
1449 if (!is_loaded()) {
1450 return;
1451 }
1452
1453 int len = methods()->length();
1454 for (int index = 0; index < len; index++) {
1455 Method* m = methods()->at(index);
1456 assert(m->is_method(), "must be method");
1457 f(m);
1458 }
1459 }
1460
1461
1462 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1463 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1464 if (fs.access_flags().is_static()) {
1465 fieldDescriptor& fd = fs.field_descriptor();
1466 cl->do_field(&fd);
1467 }
1468 }
1469 }
1470
1471
1472 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1473 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1474 if (fs.access_flags().is_static()) {
1475 fieldDescriptor& fd = fs.field_descriptor();
1476 f(&fd, mirror, CHECK);
1477 }
1478 }
1479 }
1480
1481
1482 static int compare_fields_by_offset(int* a, int* b) {
1483 return a[0] - b[0];
1484 }
1485
1486 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1487 InstanceKlass* super = superklass();
1488 if (super != NULL) {
1489 super->do_nonstatic_fields(cl);
1490 }
1491 fieldDescriptor fd;
1492 int length = java_fields_count();
1493 // In DebugInfo nonstatic fields are sorted by offset.
1494 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1495 int j = 0;
1496 for (int i = 0; i < length; i += 1) {
1497 fd.reinitialize(this, i);
1498 if (!fd.is_static()) {
1499 fields_sorted[j + 0] = fd.offset();
1500 fields_sorted[j + 1] = i;
1501 j += 2;
1502 }
1503 }
1504 if (j > 0) {
1505 length = j;
1506 // _sort_Fn is defined in growableArray.hpp.
1507 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1508 for (int i = 0; i < length; i += 2) {
1509 fd.reinitialize(this, fields_sorted[i + 1]);
1510 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1511 cl->do_field(&fd);
1512 }
1513 }
1514 FREE_C_HEAP_ARRAY(int, fields_sorted);
1515 }
1516
1517
1518 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1519 if (array_klasses() != NULL)
1520 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1521 }
1522
1523 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1524 if (array_klasses() != NULL)
1525 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1526 }
1527
1528 #ifdef ASSERT
1529 static int linear_search(const Array<Method*>* methods,
1530 const Symbol* name,
1531 const Symbol* signature) {
1532 const int len = methods->length();
1533 for (int index = 0; index < len; index++) {
1534 const Method* const m = methods->at(index);
1535 assert(m->is_method(), "must be method");
1536 if (m->signature() == signature && m->name() == name) {
1537 return index;
1538 }
1539 }
1540 return -1;
1541 }
1542 #endif
1543
1544 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1545 int len = methods->length();
1546 // methods are sorted, so do binary search
1547 int l = 0;
1548 int h = len - 1;
1549 while (l <= h) {
1550 int mid = (l + h) >> 1;
1551 Method* m = methods->at(mid);
1552 assert(m->is_method(), "must be method");
1553 int res = m->name()->fast_compare(name);
1554 if (res == 0) {
1555 return mid;
1556 } else if (res < 0) {
1557 l = mid + 1;
1558 } else {
1559 h = mid - 1;
1560 }
1561 }
1562 return -1;
1563 }
1564
1565 // find_method looks up the name/signature in the local methods array
1566 Method* InstanceKlass::find_method(const Symbol* name,
1567 const Symbol* signature) const {
1568 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1569 }
1570
1571 Method* InstanceKlass::find_method_impl(const Symbol* name,
1572 const Symbol* signature,
1573 OverpassLookupMode overpass_mode,
1574 StaticLookupMode static_mode,
1575 PrivateLookupMode private_mode) const {
1576 return InstanceKlass::find_method_impl(methods(),
1577 name,
1578 signature,
1579 overpass_mode,
1580 static_mode,
1581 private_mode);
1582 }
1583
1584 // find_instance_method looks up the name/signature in the local methods array
1585 // and skips over static methods
1586 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1587 const Symbol* name,
1588 const Symbol* signature,
1589 PrivateLookupMode private_mode) {
1590 Method* const meth = InstanceKlass::find_method_impl(methods,
1591 name,
1592 signature,
1593 find_overpass,
1594 skip_static,
1595 private_mode);
1596 assert(((meth == NULL) || !meth->is_static()),
1597 "find_instance_method should have skipped statics");
1598 return meth;
1599 }
1600
1601 // find_instance_method looks up the name/signature in the local methods array
1602 // and skips over static methods
1603 Method* InstanceKlass::find_instance_method(const Symbol* name,
1604 const Symbol* signature,
1605 PrivateLookupMode private_mode) const {
1606 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1607 }
1608
1609 // Find looks up the name/signature in the local methods array
1610 // and filters on the overpass, static and private flags
1611 // This returns the first one found
1612 // note that the local methods array can have up to one overpass, one static
1613 // and one instance (private or not) with the same name/signature
1614 Method* InstanceKlass::find_local_method(const Symbol* name,
1615 const Symbol* signature,
1616 OverpassLookupMode overpass_mode,
1617 StaticLookupMode static_mode,
1618 PrivateLookupMode private_mode) const {
1619 return InstanceKlass::find_method_impl(methods(),
1620 name,
1621 signature,
1622 overpass_mode,
1623 static_mode,
1624 private_mode);
1625 }
1626
1627 // Find looks up the name/signature in the local methods array
1628 // and filters on the overpass, static and private flags
1629 // This returns the first one found
1630 // note that the local methods array can have up to one overpass, one static
1631 // and one instance (private or not) with the same name/signature
1632 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1633 const Symbol* name,
1634 const Symbol* signature,
1635 OverpassLookupMode overpass_mode,
1636 StaticLookupMode static_mode,
1637 PrivateLookupMode private_mode) {
1638 return InstanceKlass::find_method_impl(methods,
1639 name,
1640 signature,
1641 overpass_mode,
1642 static_mode,
1643 private_mode);
1644 }
1645
1646 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1647 const Symbol* name,
1648 const Symbol* signature) {
1649 return InstanceKlass::find_method_impl(methods,
1650 name,
1651 signature,
1652 find_overpass,
1653 find_static,
1654 find_private);
1655 }
1656
1657 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1658 const Symbol* name,
1659 const Symbol* signature,
1660 OverpassLookupMode overpass_mode,
1661 StaticLookupMode static_mode,
1662 PrivateLookupMode private_mode) {
1663 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1664 return hit >= 0 ? methods->at(hit): NULL;
1665 }
1666
1667 // true if method matches signature and conforms to skipping_X conditions.
1668 static bool method_matches(const Method* m,
1669 const Symbol* signature,
1670 bool skipping_overpass,
1671 bool skipping_static,
1672 bool skipping_private) {
1673 return ((m->signature() == signature) &&
1674 (!skipping_overpass || !m->is_overpass()) &&
1675 (!skipping_static || !m->is_static()) &&
1676 (!skipping_private || !m->is_private()));
1677 }
1678
1679 // Used directly for default_methods to find the index into the
1680 // default_vtable_indices, and indirectly by find_method
1681 // find_method_index looks in the local methods array to return the index
1682 // of the matching name/signature. If, overpass methods are being ignored,
1683 // the search continues to find a potential non-overpass match. This capability
1684 // is important during method resolution to prefer a static method, for example,
1685 // over an overpass method.
1686 // There is the possibility in any _method's array to have the same name/signature
1687 // for a static method, an overpass method and a local instance method
1688 // To correctly catch a given method, the search criteria may need
1689 // to explicitly skip the other two. For local instance methods, it
1690 // is often necessary to skip private methods
1691 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1692 const Symbol* name,
1693 const Symbol* signature,
1694 OverpassLookupMode overpass_mode,
1695 StaticLookupMode static_mode,
1696 PrivateLookupMode private_mode) {
1697 const bool skipping_overpass = (overpass_mode == skip_overpass);
1698 const bool skipping_static = (static_mode == skip_static);
1699 const bool skipping_private = (private_mode == skip_private);
1700 const int hit = binary_search(methods, name);
1701 if (hit != -1) {
1702 const Method* const m = methods->at(hit);
1703
1704 // Do linear search to find matching signature. First, quick check
1705 // for common case, ignoring overpasses if requested.
1706 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1707 return hit;
1708 }
1709
1710 // search downwards through overloaded methods
1711 int i;
1712 for (i = hit - 1; i >= 0; --i) {
1713 const Method* const m = methods->at(i);
1714 assert(m->is_method(), "must be method");
1715 if (m->name() != name) {
1716 break;
1717 }
1718 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1719 return i;
1720 }
1721 }
1722 // search upwards
1723 for (i = hit + 1; i < methods->length(); ++i) {
1724 const Method* const m = methods->at(i);
1725 assert(m->is_method(), "must be method");
1726 if (m->name() != name) {
1727 break;
1728 }
1729 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1730 return i;
1731 }
1732 }
1733 // not found
1734 #ifdef ASSERT
1735 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1736 linear_search(methods, name, signature);
1737 assert(-1 == index, "binary search should have found entry %d", index);
1738 #endif
1739 }
1740 return -1;
1741 }
1742
1743 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1744 return find_method_by_name(methods(), name, end);
1745 }
1746
1747 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1748 const Symbol* name,
1749 int* end_ptr) {
1750 assert(end_ptr != NULL, "just checking");
1751 int start = binary_search(methods, name);
1752 int end = start + 1;
1753 if (start != -1) {
1754 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1755 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1756 *end_ptr = end;
1757 return start;
1758 }
1759 return -1;
1760 }
1761
1762 // uncached_lookup_method searches both the local class methods array and all
1763 // superclasses methods arrays, skipping any overpass methods in superclasses,
1764 // and possibly skipping private methods.
1765 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1766 const Symbol* signature,
1767 OverpassLookupMode overpass_mode,
1768 PrivateLookupMode private_mode) const {
1769 OverpassLookupMode overpass_local_mode = overpass_mode;
1770 const Klass* klass = this;
1771 while (klass != NULL) {
1772 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1773 signature,
1774 overpass_local_mode,
1775 find_static,
1776 private_mode);
1777 if (method != NULL) {
1778 return method;
1779 }
1780 klass = klass->super();
1781 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1782 }
1783 return NULL;
1784 }
1785
1786 #ifdef ASSERT
1787 // search through class hierarchy and return true if this class or
1788 // one of the superclasses was redefined
1789 bool InstanceKlass::has_redefined_this_or_super() const {
1790 const Klass* klass = this;
1791 while (klass != NULL) {
1792 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1793 return true;
1794 }
1795 klass = klass->super();
1796 }
1797 return false;
1798 }
1799 #endif
1800
1801 // lookup a method in the default methods list then in all transitive interfaces
1802 // Do NOT return private or static methods
1803 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1804 Symbol* signature) const {
1805 Method* m = NULL;
1806 if (default_methods() != NULL) {
1807 m = find_method(default_methods(), name, signature);
1808 }
1809 // Look up interfaces
1810 if (m == NULL) {
1811 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1812 }
1813 return m;
1814 }
1815
1816 // lookup a method in all the interfaces that this class implements
1817 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1818 // They should only be found in the initial InterfaceMethodRef
1819 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1820 Symbol* signature,
1821 DefaultsLookupMode defaults_mode) const {
1822 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1823 int num_ifs = all_ifs->length();
1824 InstanceKlass *ik = NULL;
1825 for (int i = 0; i < num_ifs; i++) {
1826 ik = all_ifs->at(i);
1827 Method* m = ik->lookup_method(name, signature);
1828 if (m != NULL && m->is_public() && !m->is_static() &&
1829 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1830 return m;
1831 }
1832 }
1833 return NULL;
1834 }
1835
1836 /* jni_id_for_impl for jfieldIds only */
1837 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1838 MutexLocker ml(JfieldIdCreation_lock);
1839 // Retry lookup after we got the lock
1840 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1841 if (probe == NULL) {
1842 // Slow case, allocate new static field identifier
1843 probe = new JNIid(this, offset, jni_ids());
1844 set_jni_ids(probe);
1845 }
1846 return probe;
1847 }
1848
1849
1850 /* jni_id_for for jfieldIds only */
1851 JNIid* InstanceKlass::jni_id_for(int offset) {
1852 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1853 if (probe == NULL) {
1854 probe = jni_id_for_impl(offset);
1855 }
1856 return probe;
1857 }
1858
1859 u2 InstanceKlass::enclosing_method_data(int offset) const {
1860 const Array<jushort>* const inner_class_list = inner_classes();
1861 if (inner_class_list == NULL) {
1862 return 0;
1863 }
1864 const int length = inner_class_list->length();
1865 if (length % inner_class_next_offset == 0) {
1866 return 0;
1867 }
1868 const int index = length - enclosing_method_attribute_size;
1869 assert(offset < enclosing_method_attribute_size, "invalid offset");
1870 return inner_class_list->at(index + offset);
1871 }
1872
1873 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1874 u2 method_index) {
1875 Array<jushort>* inner_class_list = inner_classes();
1876 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1877 int length = inner_class_list->length();
1878 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1879 int index = length - enclosing_method_attribute_size;
1880 inner_class_list->at_put(
1881 index + enclosing_method_class_index_offset, class_index);
1882 inner_class_list->at_put(
1883 index + enclosing_method_method_index_offset, method_index);
1884 }
1885 }
1886
1887 // Lookup or create a jmethodID.
1888 // This code is called by the VMThread and JavaThreads so the
1889 // locking has to be done very carefully to avoid deadlocks
1890 // and/or other cache consistency problems.
1891 //
1892 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1893 size_t idnum = (size_t)method_h->method_idnum();
1894 jmethodID* jmeths = methods_jmethod_ids_acquire();
1895 size_t length = 0;
1896 jmethodID id = NULL;
1897
1898 // We use a double-check locking idiom here because this cache is
1899 // performance sensitive. In the normal system, this cache only
1900 // transitions from NULL to non-NULL which is safe because we use
1901 // release_set_methods_jmethod_ids() to advertise the new cache.
1902 // A partially constructed cache should never be seen by a racing
1903 // thread. We also use release_store() to save a new jmethodID
1904 // in the cache so a partially constructed jmethodID should never be
1905 // seen either. Cache reads of existing jmethodIDs proceed without a
1906 // lock, but cache writes of a new jmethodID requires uniqueness and
1907 // creation of the cache itself requires no leaks so a lock is
1908 // generally acquired in those two cases.
1909 //
1910 // If the RedefineClasses() API has been used, then this cache can
1911 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1912 // Cache creation requires no leaks and we require safety between all
1913 // cache accesses and freeing of the old cache so a lock is generally
1914 // acquired when the RedefineClasses() API has been used.
1915
1916 if (jmeths != NULL) {
1917 // the cache already exists
1918 if (!idnum_can_increment()) {
1919 // the cache can't grow so we can just get the current values
1920 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1921 } else {
1922 // cache can grow so we have to be more careful
1923 if (Threads::number_of_threads() == 0 ||
1924 SafepointSynchronize::is_at_safepoint()) {
1925 // we're single threaded or at a safepoint - no locking needed
1926 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1927 } else {
1928 MutexLocker ml(JmethodIdCreation_lock);
1929 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1930 }
1931 }
1932 }
1933 // implied else:
1934 // we need to allocate a cache so default length and id values are good
1935
1936 if (jmeths == NULL || // no cache yet
1937 length <= idnum || // cache is too short
1938 id == NULL) { // cache doesn't contain entry
1939
1940 // This function can be called by the VMThread so we have to do all
1941 // things that might block on a safepoint before grabbing the lock.
1942 // Otherwise, we can deadlock with the VMThread or have a cache
1943 // consistency issue. These vars keep track of what we might have
1944 // to free after the lock is dropped.
1945 jmethodID to_dealloc_id = NULL;
1946 jmethodID* to_dealloc_jmeths = NULL;
1947
1948 // may not allocate new_jmeths or use it if we allocate it
1949 jmethodID* new_jmeths = NULL;
1950 if (length <= idnum) {
1951 // allocate a new cache that might be used
1952 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1953 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1954 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1955 // cache size is stored in element[0], other elements offset by one
1956 new_jmeths[0] = (jmethodID)size;
1957 }
1958
1959 // allocate a new jmethodID that might be used
1960 jmethodID new_id = NULL;
1961 if (method_h->is_old() && !method_h->is_obsolete()) {
1962 // The method passed in is old (but not obsolete), we need to use the current version
1963 Method* current_method = method_with_idnum((int)idnum);
1964 assert(current_method != NULL, "old and but not obsolete, so should exist");
1965 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1966 } else {
1967 // It is the current version of the method or an obsolete method,
1968 // use the version passed in
1969 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1970 }
1971
1972 if (Threads::number_of_threads() == 0 ||
1973 SafepointSynchronize::is_at_safepoint()) {
1974 // we're single threaded or at a safepoint - no locking needed
1975 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1976 &to_dealloc_id, &to_dealloc_jmeths);
1977 } else {
1978 MutexLocker ml(JmethodIdCreation_lock);
1979 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1980 &to_dealloc_id, &to_dealloc_jmeths);
1981 }
1982
1983 // The lock has been dropped so we can free resources.
1984 // Free up either the old cache or the new cache if we allocated one.
1985 if (to_dealloc_jmeths != NULL) {
1986 FreeHeap(to_dealloc_jmeths);
1987 }
1988 // free up the new ID since it wasn't needed
1989 if (to_dealloc_id != NULL) {
1990 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1991 }
1992 }
1993 return id;
1994 }
1995
1996 // Figure out how many jmethodIDs haven't been allocated, and make
1997 // sure space for them is pre-allocated. This makes getting all
1998 // method ids much, much faster with classes with more than 8
1999 // methods, and has a *substantial* effect on performance with jvmti
2000 // code that loads all jmethodIDs for all classes.
2001 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2002 int new_jmeths = 0;
2003 int length = methods()->length();
2004 for (int index = start_offset; index < length; index++) {
2005 Method* m = methods()->at(index);
2006 jmethodID id = m->find_jmethod_id_or_null();
2007 if (id == NULL) {
2008 new_jmeths++;
2009 }
2010 }
2011 if (new_jmeths != 0) {
2012 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2013 }
2014 }
2015
2016 // Common code to fetch the jmethodID from the cache or update the
2017 // cache with the new jmethodID. This function should never do anything
2018 // that causes the caller to go to a safepoint or we can deadlock with
2019 // the VMThread or have cache consistency issues.
2020 //
2021 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2022 size_t idnum, jmethodID new_id,
2023 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2024 jmethodID** to_dealloc_jmeths_p) {
2025 assert(new_id != NULL, "sanity check");
2026 assert(to_dealloc_id_p != NULL, "sanity check");
2027 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2028 assert(Threads::number_of_threads() == 0 ||
2029 SafepointSynchronize::is_at_safepoint() ||
2030 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2031
2032 // reacquire the cache - we are locked, single threaded or at a safepoint
2033 jmethodID* jmeths = methods_jmethod_ids_acquire();
2034 jmethodID id = NULL;
2035 size_t length = 0;
2036
2037 if (jmeths == NULL || // no cache yet
2038 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2039 if (jmeths != NULL) {
2040 // copy any existing entries from the old cache
2041 for (size_t index = 0; index < length; index++) {
2042 new_jmeths[index+1] = jmeths[index+1];
2043 }
2044 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2045 }
2046 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2047 } else {
2048 // fetch jmethodID (if any) from the existing cache
2049 id = jmeths[idnum+1];
2050 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2051 }
2052 if (id == NULL) {
2053 // No matching jmethodID in the existing cache or we have a new
2054 // cache or we just grew the cache. This cache write is done here
2055 // by the first thread to win the foot race because a jmethodID
2056 // needs to be unique once it is generally available.
2057 id = new_id;
2058
2059 // The jmethodID cache can be read while unlocked so we have to
2060 // make sure the new jmethodID is complete before installing it
2061 // in the cache.
2062 OrderAccess::release_store(&jmeths[idnum+1], id);
2063 } else {
2064 *to_dealloc_id_p = new_id; // save new id for later delete
2065 }
2066 return id;
2067 }
2068
2069
2070 // Common code to get the jmethodID cache length and the jmethodID
2071 // value at index idnum if there is one.
2072 //
2073 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2074 size_t idnum, size_t *length_p, jmethodID* id_p) {
2075 assert(cache != NULL, "sanity check");
2076 assert(length_p != NULL, "sanity check");
2077 assert(id_p != NULL, "sanity check");
2078
2079 // cache size is stored in element[0], other elements offset by one
2080 *length_p = (size_t)cache[0];
2081 if (*length_p <= idnum) { // cache is too short
2082 *id_p = NULL;
2083 } else {
2084 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2085 }
2086 }
2087
2088
2089 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2090 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2091 size_t idnum = (size_t)method->method_idnum();
2092 jmethodID* jmeths = methods_jmethod_ids_acquire();
2093 size_t length; // length assigned as debugging crumb
2094 jmethodID id = NULL;
2095 if (jmeths != NULL && // If there is a cache
2096 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2097 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2098 }
2099 return id;
2100 }
2101
2102 inline DependencyContext InstanceKlass::dependencies() {
2103 DependencyContext dep_context(&_dep_context);
2104 return dep_context;
2105 }
2106
2107 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2108 return dependencies().mark_dependent_nmethods(changes);
2109 }
2110
2111 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2112 dependencies().add_dependent_nmethod(nm);
2113 }
2114
2115 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2116 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2117 }
2118
2119 #ifndef PRODUCT
2120 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2121 dependencies().print_dependent_nmethods(verbose);
2122 }
2123
2124 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2125 return dependencies().is_dependent_nmethod(nm);
2126 }
2127 #endif //PRODUCT
2128
2129 void InstanceKlass::clean_weak_instanceklass_links() {
2130 clean_implementors_list();
2131 clean_method_data();
2132
2133 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2134 DependencyContext dep_context(&_dep_context);
2135 dep_context.expunge_stale_entries();
2136 }
2137
2138 void InstanceKlass::clean_implementors_list() {
2139 assert(is_loader_alive(), "this klass should be live");
2140 if (is_interface()) {
2141 if (ClassUnloading) {
2142 Klass* impl = implementor();
2143 if (impl != NULL) {
2144 if (!impl->is_loader_alive()) {
2145 // remove this guy
2146 Klass** klass = adr_implementor();
2147 assert(klass != NULL, "null klass");
2148 if (klass != NULL) {
2149 *klass = NULL;
2150 }
2151 }
2152 }
2153 }
2154 }
2155 }
2156
2157 void InstanceKlass::clean_method_data() {
2158 for (int m = 0; m < methods()->length(); m++) {
2159 MethodData* mdo = methods()->at(m)->method_data();
2160 if (mdo != NULL) {
2161 mdo->clean_method_data(/*always_clean*/false);
2162 }
2163 }
2164 }
2165
2166 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2167 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2168 ResourceMark rm;
2169 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2170 return false;
2171 }
2172
2173 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2174 if (local_interfaces != NULL) {
2175 int length = local_interfaces->length();
2176 for (int i = 0; i < length; i++) {
2177 InstanceKlass* intf = local_interfaces->at(i);
2178 if (!intf->has_passed_fingerprint_check()) {
2179 ResourceMark rm;
2180 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2181 return false;
2182 }
2183 }
2184 }
2185
2186 return true;
2187 }
2188
2189 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2190 #if INCLUDE_AOT
2191 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2192 if (CalculateClassFingerprint) {
2193 // (1) We are running AOT to generate a shared library.
2194 return true;
2195 }
2196 if (DumpSharedSpaces) {
2197 // (2) We are running -Xshare:dump to create a shared archive
2198 return true;
2199 }
2200 if (UseAOT && is_unsafe_anonymous) {
2201 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2202 return true;
2203 }
2204 #endif
2205
2206 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2207 // but do not store the 64-bit fingerprint to save space.
2208 return false;
2209 }
2210
2211 bool InstanceKlass::has_stored_fingerprint() const {
2212 #if INCLUDE_AOT
2213 return should_store_fingerprint() || is_shared();
2214 #else
2215 return false;
2216 #endif
2217 }
2218
2219 uint64_t InstanceKlass::get_stored_fingerprint() const {
2220 address adr = adr_fingerprint();
2221 if (adr != NULL) {
2222 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2223 }
2224 return 0;
2225 }
2226
2227 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2228 address adr = adr_fingerprint();
2229 if (adr != NULL) {
2230 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2231
2232 ResourceMark rm;
2233 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2234 }
2235 }
2236
2237 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2238 Klass::metaspace_pointers_do(it);
2239
2240 if (log_is_enabled(Trace, cds)) {
2241 ResourceMark rm;
2242 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2243 }
2244
2245 it->push(&_annotations);
2246 it->push((Klass**)&_array_klasses);
2247 it->push(&_constants);
2248 it->push(&_inner_classes);
2249 it->push(&_array_name);
2250 #if INCLUDE_JVMTI
2251 it->push(&_previous_versions);
2252 #endif
2253 it->push(&_methods);
2254 it->push(&_default_methods);
2255 it->push(&_local_interfaces);
2256 it->push(&_transitive_interfaces);
2257 it->push(&_method_ordering);
2258 it->push(&_default_vtable_indices);
2259 it->push(&_fields);
2260
2261 if (itable_length() > 0) {
2262 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2263 int method_table_offset_in_words = ioe->offset()/wordSize;
2264 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2265 / itableOffsetEntry::size();
2266
2267 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2268 if (ioe->interface_klass() != NULL) {
2269 it->push(ioe->interface_klass_addr());
2270 itableMethodEntry* ime = ioe->first_method_entry(this);
2271 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2272 for (int index = 0; index < n; index ++) {
2273 it->push(ime[index].method_addr());
2274 }
2275 }
2276 }
2277 }
2278
2279 it->push(&_nest_members);
2280 }
2281
2282 void InstanceKlass::remove_unshareable_info() {
2283 Klass::remove_unshareable_info();
2284
2285 if (is_in_error_state()) {
2286 // Classes are attempted to link during dumping and may fail,
2287 // but these classes are still in the dictionary and class list in CLD.
2288 // Check in_error state first because in_error is > linked state, so
2289 // is_linked() is true.
2290 // If there's a linking error, there is nothing else to remove.
2291 return;
2292 }
2293
2294 // Reset to the 'allocated' state to prevent any premature accessing to
2295 // a shared class at runtime while the class is still being loaded and
2296 // restored. A class' init_state is set to 'loaded' at runtime when it's
2297 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2298 _init_state = allocated;
2299
2300 {
2301 MutexLocker ml(Compile_lock);
2302 init_implementor();
2303 }
2304
2305 constants()->remove_unshareable_info();
2306
2307 for (int i = 0; i < methods()->length(); i++) {
2308 Method* m = methods()->at(i);
2309 m->remove_unshareable_info();
2310 }
2311
2312 // do array classes also.
2313 if (array_klasses() != NULL) {
2314 array_klasses()->remove_unshareable_info();
2315 }
2316
2317 // These are not allocated from metaspace, but they should should all be empty
2318 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2319 guarantee(_source_debug_extension == NULL, "must be");
2320 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2321 guarantee(_osr_nmethods_head == NULL, "must be");
2322
2323 #if INCLUDE_JVMTI
2324 guarantee(_breakpoints == NULL, "must be");
2325 guarantee(_previous_versions == NULL, "must be");
2326 #endif
2327
2328 _init_thread = NULL;
2329 _methods_jmethod_ids = NULL;
2330 _jni_ids = NULL;
2331 _oop_map_cache = NULL;
2332 // clear _nest_host to ensure re-load at runtime
2333 _nest_host = NULL;
2334 }
2335
2336 void InstanceKlass::remove_java_mirror() {
2337 Klass::remove_java_mirror();
2338
2339 // do array classes also.
2340 if (array_klasses() != NULL) {
2341 array_klasses()->remove_java_mirror();
2342 }
2343 }
2344
2345 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2346 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2347 // before the InstanceKlass is added to the SystemDictionary. Make
2348 // sure the current state is <loaded.
2349 assert(!is_loaded(), "invalid init state");
2350 set_package(loader_data, CHECK);
2351 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2352
2353 Array<Method*>* methods = this->methods();
2354 int num_methods = methods->length();
2355 for (int index2 = 0; index2 < num_methods; ++index2) {
2356 methodHandle m(THREAD, methods->at(index2));
2357 m->restore_unshareable_info(CHECK);
2358 }
2359 if (JvmtiExport::has_redefined_a_class()) {
2360 // Reinitialize vtable because RedefineClasses may have changed some
2361 // entries in this vtable for super classes so the CDS vtable might
2362 // point to old or obsolete entries. RedefineClasses doesn't fix up
2363 // vtables in the shared system dictionary, only the main one.
2364 // It also redefines the itable too so fix that too.
2365 vtable().initialize_vtable(false, CHECK);
2366 itable().initialize_itable(false, CHECK);
2367 }
2368
2369 // restore constant pool resolved references
2370 constants()->restore_unshareable_info(CHECK);
2371
2372 if (array_klasses() != NULL) {
2373 // Array classes have null protection domain.
2374 // --> see ArrayKlass::complete_create_array_klass()
2375 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2376 }
2377 }
2378
2379 // returns true IFF is_in_error_state() has been changed as a result of this call.
2380 bool InstanceKlass::check_sharing_error_state() {
2381 assert(DumpSharedSpaces, "should only be called during dumping");
2382 bool old_state = is_in_error_state();
2383
2384 if (!is_in_error_state()) {
2385 bool bad = false;
2386 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2387 if (sup->is_in_error_state()) {
2388 bad = true;
2389 break;
2390 }
2391 }
2392 if (!bad) {
2393 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2394 for (int i = 0; i < interfaces->length(); i++) {
2395 InstanceKlass* iface = interfaces->at(i);
2396 if (iface->is_in_error_state()) {
2397 bad = true;
2398 break;
2399 }
2400 }
2401 }
2402
2403 if (bad) {
2404 set_in_error_state();
2405 }
2406 }
2407
2408 return (old_state != is_in_error_state());
2409 }
2410
2411 #if INCLUDE_JVMTI
2412 static void clear_all_breakpoints(Method* m) {
2413 m->clear_all_breakpoints();
2414 }
2415 #endif
2416
2417 void InstanceKlass::unload_class(InstanceKlass* ik) {
2418 // Release dependencies.
2419 ik->dependencies().remove_all_dependents();
2420
2421 // notify the debugger
2422 if (JvmtiExport::should_post_class_unload()) {
2423 JvmtiExport::post_class_unload(ik);
2424 }
2425
2426 // notify ClassLoadingService of class unload
2427 ClassLoadingService::notify_class_unloaded(ik);
2428
2429 #if INCLUDE_JFR
2430 assert(ik != NULL, "invariant");
2431 EventClassUnload event;
2432 event.set_unloadedClass(ik);
2433 event.set_definingClassLoader(ik->class_loader_data());
2434 event.commit();
2435 #endif
2436 }
2437
2438 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2439 // Clean up C heap
2440 ik->release_C_heap_structures();
2441 ik->constants()->release_C_heap_structures();
2442 }
2443
2444 void InstanceKlass::release_C_heap_structures() {
2445 // Can't release the constant pool here because the constant pool can be
2446 // deallocated separately from the InstanceKlass for default methods and
2447 // redefine classes.
2448
2449 // Deallocate oop map cache
2450 if (_oop_map_cache != NULL) {
2451 delete _oop_map_cache;
2452 _oop_map_cache = NULL;
2453 }
2454
2455 // Deallocate JNI identifiers for jfieldIDs
2456 JNIid::deallocate(jni_ids());
2457 set_jni_ids(NULL);
2458
2459 jmethodID* jmeths = methods_jmethod_ids_acquire();
2460 if (jmeths != (jmethodID*)NULL) {
2461 release_set_methods_jmethod_ids(NULL);
2462 FreeHeap(jmeths);
2463 }
2464
2465 assert(_dep_context == DependencyContext::EMPTY,
2466 "dependencies should already be cleaned");
2467
2468 #if INCLUDE_JVMTI
2469 // Deallocate breakpoint records
2470 if (breakpoints() != 0x0) {
2471 methods_do(clear_all_breakpoints);
2472 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2473 }
2474
2475 // deallocate the cached class file
2476 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2477 os::free(_cached_class_file);
2478 _cached_class_file = NULL;
2479 }
2480 #endif
2481
2482 // Decrement symbol reference counts associated with the unloaded class.
2483 if (_name != NULL) _name->decrement_refcount();
2484 // unreference array name derived from this class name (arrays of an unloaded
2485 // class can't be referenced anymore).
2486 if (_array_name != NULL) _array_name->decrement_refcount();
2487 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2488 }
2489
2490 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2491 if (array == NULL) {
2492 _source_debug_extension = NULL;
2493 } else {
2494 // Adding one to the attribute length in order to store a null terminator
2495 // character could cause an overflow because the attribute length is
2496 // already coded with an u4 in the classfile, but in practice, it's
2497 // unlikely to happen.
2498 assert((length+1) > length, "Overflow checking");
2499 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2500 for (int i = 0; i < length; i++) {
2501 sde[i] = array[i];
2502 }
2503 sde[length] = '\0';
2504 _source_debug_extension = sde;
2505 }
2506 }
2507
2508 const char* InstanceKlass::signature_name() const {
2509 int hash_len = 0;
2510 char hash_buf[40];
2511
2512 // If this is an unsafe anonymous class, append a hash to make the name unique
2513 if (is_unsafe_anonymous()) {
2514 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2515 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2516 hash_len = (int)strlen(hash_buf);
2517 }
2518
2519 // Get the internal name as a c string
2520 const char* src = (const char*) (name()->as_C_string());
2521 const int src_length = (int)strlen(src);
2522
2523 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2524
2525 // Add L as type indicator
2526 int dest_index = 0;
2527 dest[dest_index++] = 'L';
2528
2529 // Add the actual class name
2530 for (int src_index = 0; src_index < src_length; ) {
2531 dest[dest_index++] = src[src_index++];
2532 }
2533
2534 // If we have a hash, append it
2535 for (int hash_index = 0; hash_index < hash_len; ) {
2536 dest[dest_index++] = hash_buf[hash_index++];
2537 }
2538
2539 // Add the semicolon and the NULL
2540 dest[dest_index++] = ';';
2541 dest[dest_index] = '\0';
2542 return dest;
2543 }
2544
2545 // Used to obtain the package name from a fully qualified class name.
2546 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2547 if (name == NULL) {
2548 return NULL;
2549 } else {
2550 if (name->utf8_length() <= 0) {
2551 return NULL;
2552 }
2553 ResourceMark rm;
2554 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2555 if (package_name == NULL) {
2556 return NULL;
2557 }
2558 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2559 return pkg_name;
2560 }
2561 }
2562
2563 ModuleEntry* InstanceKlass::module() const {
2564 // For an unsafe anonymous class return the host class' module
2565 if (is_unsafe_anonymous()) {
2566 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2567 return unsafe_anonymous_host()->module();
2568 }
2569
2570 // Class is in a named package
2571 if (!in_unnamed_package()) {
2572 return _package_entry->module();
2573 }
2574
2575 // Class is in an unnamed package, return its loader's unnamed module
2576 return class_loader_data()->unnamed_module();
2577 }
2578
2579 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2580
2581 // ensure java/ packages only loaded by boot or platform builtin loaders
2582 check_prohibited_package(name(), loader_data, CHECK);
2583
2584 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2585
2586 if (pkg_name != NULL && loader_data != NULL) {
2587
2588 // Find in class loader's package entry table.
2589 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2590
2591 // If the package name is not found in the loader's package
2592 // entry table, it is an indication that the package has not
2593 // been defined. Consider it defined within the unnamed module.
2594 if (_package_entry == NULL) {
2595 ResourceMark rm;
2596
2597 if (!ModuleEntryTable::javabase_defined()) {
2598 // Before java.base is defined during bootstrapping, define all packages in
2599 // the java.base module. If a non-java.base package is erroneously placed
2600 // in the java.base module it will be caught later when java.base
2601 // is defined by ModuleEntryTable::verify_javabase_packages check.
2602 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2603 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2604 } else {
2605 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2606 _package_entry = loader_data->packages()->lookup(pkg_name,
2607 loader_data->unnamed_module());
2608 }
2609
2610 // A package should have been successfully created
2611 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2612 name()->as_C_string(), loader_data->loader_name_and_id());
2613 }
2614
2615 if (log_is_enabled(Debug, module)) {
2616 ResourceMark rm;
2617 ModuleEntry* m = _package_entry->module();
2618 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2619 external_name(),
2620 pkg_name->as_C_string(),
2621 loader_data->loader_name_and_id(),
2622 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2623 }
2624 } else {
2625 ResourceMark rm;
2626 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2627 external_name(),
2628 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2629 UNNAMED_MODULE);
2630 }
2631 }
2632
2633
2634 // different versions of is_same_class_package
2635
2636 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2637 oop classloader1 = this->class_loader();
2638 PackageEntry* classpkg1 = this->package();
2639 if (class2->is_objArray_klass()) {
2640 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2641 }
2642
2643 oop classloader2;
2644 PackageEntry* classpkg2;
2645 if (class2->is_instance_klass()) {
2646 classloader2 = class2->class_loader();
2647 classpkg2 = class2->package();
2648 } else {
2649 assert(class2->is_typeArray_klass(), "should be type array");
2650 classloader2 = NULL;
2651 classpkg2 = NULL;
2652 }
2653
2654 // Same package is determined by comparing class loader
2655 // and package entries. Both must be the same. This rule
2656 // applies even to classes that are defined in the unnamed
2657 // package, they still must have the same class loader.
2658 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2659 return true;
2660 }
2661
2662 return false;
2663 }
2664
2665 // return true if this class and other_class are in the same package. Classloader
2666 // and classname information is enough to determine a class's package
2667 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2668 const Symbol* other_class_name) const {
2669 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2670 return false;
2671 }
2672 if (name()->fast_compare(other_class_name) == 0) {
2673 return true;
2674 }
2675
2676 {
2677 ResourceMark rm;
2678
2679 bool bad_class_name = false;
2680 const char* other_pkg =
2681 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2682 if (bad_class_name) {
2683 return false;
2684 }
2685 // Check that package_from_name() returns NULL, not "", if there is no package.
2686 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2687
2688 const Symbol* const this_package_name =
2689 this->package() != NULL ? this->package()->name() : NULL;
2690
2691 if (this_package_name == NULL || other_pkg == NULL) {
2692 // One of the two doesn't have a package. Only return true if the other
2693 // one also doesn't have a package.
2694 return (const char*)this_package_name == other_pkg;
2695 }
2696
2697 // Check if package is identical
2698 return this_package_name->equals(other_pkg);
2699 }
2700 }
2701
2702 // Returns true iff super_method can be overridden by a method in targetclassname
2703 // See JLS 3rd edition 8.4.6.1
2704 // Assumes name-signature match
2705 // "this" is InstanceKlass of super_method which must exist
2706 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2707 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2708 // Private methods can not be overridden
2709 if (super_method->is_private()) {
2710 return false;
2711 }
2712 // If super method is accessible, then override
2713 if ((super_method->is_protected()) ||
2714 (super_method->is_public())) {
2715 return true;
2716 }
2717 // Package-private methods are not inherited outside of package
2718 assert(super_method->is_package_private(), "must be package private");
2719 return(is_same_class_package(targetclassloader(), targetclassname));
2720 }
2721
2722 // Only boot and platform class loaders can define classes in "java/" packages.
2723 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2724 ClassLoaderData* loader_data,
2725 TRAPS) {
2726 if (!loader_data->is_boot_class_loader_data() &&
2727 !loader_data->is_platform_class_loader_data() &&
2728 class_name != NULL) {
2729 ResourceMark rm(THREAD);
2730 char* name = class_name->as_C_string();
2731 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2732 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2733 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2734 name = pkg_name->as_C_string();
2735 const char* class_loader_name = loader_data->loader_name_and_id();
2736 StringUtils::replace_no_expand(name, "/", ".");
2737 const char* msg_text1 = "Class loader (instance of): ";
2738 const char* msg_text2 = " tried to load prohibited package name: ";
2739 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2740 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2741 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2742 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2743 }
2744 }
2745 return;
2746 }
2747
2748 // tell if two classes have the same enclosing class (at package level)
2749 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2750 if (class2 == this) return true;
2751 if (!class2->is_instance_klass()) return false;
2752
2753 // must be in same package before we try anything else
2754 if (!is_same_class_package(class2))
2755 return false;
2756
2757 // As long as there is an outer_this.getEnclosingClass,
2758 // shift the search outward.
2759 const InstanceKlass* outer_this = this;
2760 for (;;) {
2761 // As we walk along, look for equalities between outer_this and class2.
2762 // Eventually, the walks will terminate as outer_this stops
2763 // at the top-level class around the original class.
2764 bool ignore_inner_is_member;
2765 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2766 CHECK_false);
2767 if (next == NULL) break;
2768 if (next == class2) return true;
2769 outer_this = InstanceKlass::cast(next);
2770 }
2771
2772 // Now do the same for class2.
2773 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2774 for (;;) {
2775 bool ignore_inner_is_member;
2776 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2777 CHECK_false);
2778 if (next == NULL) break;
2779 // Might as well check the new outer against all available values.
2780 if (next == this) return true;
2781 if (next == outer_this) return true;
2782 outer2 = InstanceKlass::cast(next);
2783 }
2784
2785 // If by this point we have not found an equality between the
2786 // two classes, we know they are in separate package members.
2787 return false;
2788 }
2789
2790 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2791 constantPoolHandle i_cp(THREAD, constants());
2792 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2793 int ioff = iter.inner_class_info_index();
2794 if (ioff != 0) {
2795 // Check to see if the name matches the class we're looking for
2796 // before attempting to find the class.
2797 if (i_cp->klass_name_at_matches(this, ioff)) {
2798 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2799 if (this == inner_klass) {
2800 *ooff = iter.outer_class_info_index();
2801 *noff = iter.inner_name_index();
2802 return true;
2803 }
2804 }
2805 }
2806 }
2807 return false;
2808 }
2809
2810 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2811 InstanceKlass* outer_klass = NULL;
2812 *inner_is_member = false;
2813 int ooff = 0, noff = 0;
2814 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2815 if (has_inner_classes_attr) {
2816 constantPoolHandle i_cp(THREAD, constants());
2817 if (ooff != 0) {
2818 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2819 outer_klass = InstanceKlass::cast(ok);
2820 *inner_is_member = true;
2821 }
2822 if (NULL == outer_klass) {
2823 // It may be unsafe anonymous; try for that.
2824 int encl_method_class_idx = enclosing_method_class_index();
2825 if (encl_method_class_idx != 0) {
2826 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2827 outer_klass = InstanceKlass::cast(ok);
2828 *inner_is_member = false;
2829 }
2830 }
2831 }
2832
2833 // If no inner class attribute found for this class.
2834 if (NULL == outer_klass) return NULL;
2835
2836 // Throws an exception if outer klass has not declared k as an inner klass
2837 // We need evidence that each klass knows about the other, or else
2838 // the system could allow a spoof of an inner class to gain access rights.
2839 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2840 return outer_klass;
2841 }
2842
2843 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2844 jint access = access_flags().as_int();
2845
2846 // But check if it happens to be member class.
2847 InnerClassesIterator iter(this);
2848 for (; !iter.done(); iter.next()) {
2849 int ioff = iter.inner_class_info_index();
2850 // Inner class attribute can be zero, skip it.
2851 // Strange but true: JVM spec. allows null inner class refs.
2852 if (ioff == 0) continue;
2853
2854 // only look at classes that are already loaded
2855 // since we are looking for the flags for our self.
2856 Symbol* inner_name = constants()->klass_name_at(ioff);
2857 if (name() == inner_name) {
2858 // This is really a member class.
2859 access = iter.inner_access_flags();
2860 break;
2861 }
2862 }
2863 // Remember to strip ACC_SUPER bit
2864 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2865 }
2866
2867 jint InstanceKlass::jvmti_class_status() const {
2868 jint result = 0;
2869
2870 if (is_linked()) {
2871 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2872 }
2873
2874 if (is_initialized()) {
2875 assert(is_linked(), "Class status is not consistent");
2876 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2877 }
2878 if (is_in_error_state()) {
2879 result |= JVMTI_CLASS_STATUS_ERROR;
2880 }
2881 return result;
2882 }
2883
2884 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2885 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2886 int method_table_offset_in_words = ioe->offset()/wordSize;
2887 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2888 / itableOffsetEntry::size();
2889
2890 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2891 // If the interface isn't implemented by the receiver class,
2892 // the VM should throw IncompatibleClassChangeError.
2893 if (cnt >= nof_interfaces) {
2894 ResourceMark rm(THREAD);
2895 stringStream ss;
2896 bool same_module = (module() == holder->module());
2897 ss.print("Receiver class %s does not implement "
2898 "the interface %s defining the method to be called "
2899 "(%s%s%s)",
2900 external_name(), holder->external_name(),
2901 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2902 (same_module) ? "" : "; ",
2903 (same_module) ? "" : holder->class_in_module_of_loader());
2904 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2905 }
2906
2907 Klass* ik = ioe->interface_klass();
2908 if (ik == holder) break;
2909 }
2910
2911 itableMethodEntry* ime = ioe->first_method_entry(this);
2912 Method* m = ime[index].method();
2913 if (m == NULL) {
2914 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2915 }
2916 return m;
2917 }
2918
2919
2920 #if INCLUDE_JVMTI
2921 // update default_methods for redefineclasses for methods that are
2922 // not yet in the vtable due to concurrent subclass define and superinterface
2923 // redefinition
2924 // Note: those in the vtable, should have been updated via adjust_method_entries
2925 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2926 // search the default_methods for uses of either obsolete or EMCP methods
2927 if (default_methods() != NULL) {
2928 for (int index = 0; index < default_methods()->length(); index ++) {
2929 Method* old_method = default_methods()->at(index);
2930 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2931 continue; // skip uninteresting entries
2932 }
2933 assert(!old_method->is_deleted(), "default methods may not be deleted");
2934
2935 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2936
2937 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2938 assert(old_method != new_method, "sanity check");
2939
2940 default_methods()->at_put(index, new_method);
2941 if (log_is_enabled(Info, redefine, class, update)) {
2942 ResourceMark rm;
2943 if (!(*trace_name_printed)) {
2944 log_info(redefine, class, update)
2945 ("adjust: klassname=%s default methods from name=%s",
2946 external_name(), old_method->method_holder()->external_name());
2947 *trace_name_printed = true;
2948 }
2949 log_debug(redefine, class, update, vtables)
2950 ("default method update: %s(%s) ",
2951 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2952 }
2953 }
2954 }
2955 }
2956 #endif // INCLUDE_JVMTI
2957
2958 // On-stack replacement stuff
2959 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2960 // only one compilation can be active
2961 {
2962 // This is a short non-blocking critical region, so the no safepoint check is ok.
2963 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2964 assert(n->is_osr_method(), "wrong kind of nmethod");
2965 n->set_osr_link(osr_nmethods_head());
2966 set_osr_nmethods_head(n);
2967 // Raise the highest osr level if necessary
2968 if (TieredCompilation) {
2969 Method* m = n->method();
2970 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2971 }
2972 }
2973
2974 // Get rid of the osr methods for the same bci that have lower levels.
2975 if (TieredCompilation) {
2976 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2977 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2978 if (inv != NULL && inv->is_in_use()) {
2979 inv->make_not_entrant();
2980 }
2981 }
2982 }
2983 }
2984
2985 // Remove osr nmethod from the list. Return true if found and removed.
2986 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2987 // This is a short non-blocking critical region, so the no safepoint check is ok.
2988 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2989 assert(n->is_osr_method(), "wrong kind of nmethod");
2990 nmethod* last = NULL;
2991 nmethod* cur = osr_nmethods_head();
2992 int max_level = CompLevel_none; // Find the max comp level excluding n
2993 Method* m = n->method();
2994 // Search for match
2995 bool found = false;
2996 while(cur != NULL && cur != n) {
2997 if (TieredCompilation && m == cur->method()) {
2998 // Find max level before n
2999 max_level = MAX2(max_level, cur->comp_level());
3000 }
3001 last = cur;
3002 cur = cur->osr_link();
3003 }
3004 nmethod* next = NULL;
3005 if (cur == n) {
3006 found = true;
3007 next = cur->osr_link();
3008 if (last == NULL) {
3009 // Remove first element
3010 set_osr_nmethods_head(next);
3011 } else {
3012 last->set_osr_link(next);
3013 }
3014 }
3015 n->set_osr_link(NULL);
3016 if (TieredCompilation) {
3017 cur = next;
3018 while (cur != NULL) {
3019 // Find max level after n
3020 if (m == cur->method()) {
3021 max_level = MAX2(max_level, cur->comp_level());
3022 }
3023 cur = cur->osr_link();
3024 }
3025 m->set_highest_osr_comp_level(max_level);
3026 }
3027 return found;
3028 }
3029
3030 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3031 // This is a short non-blocking critical region, so the no safepoint check is ok.
3032 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3033 nmethod* osr = osr_nmethods_head();
3034 int found = 0;
3035 while (osr != NULL) {
3036 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3037 if (osr->method() == m) {
3038 osr->mark_for_deoptimization();
3039 found++;
3040 }
3041 osr = osr->osr_link();
3042 }
3043 return found;
3044 }
3045
3046 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3047 // This is a short non-blocking critical region, so the no safepoint check is ok.
3048 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3049 nmethod* osr = osr_nmethods_head();
3050 nmethod* best = NULL;
3051 while (osr != NULL) {
3052 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3053 // There can be a time when a c1 osr method exists but we are waiting
3054 // for a c2 version. When c2 completes its osr nmethod we will trash
3055 // the c1 version and only be able to find the c2 version. However
3056 // while we overflow in the c1 code at back branches we don't want to
3057 // try and switch to the same code as we are already running
3058
3059 if (osr->method() == m &&
3060 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3061 if (match_level) {
3062 if (osr->comp_level() == comp_level) {
3063 // Found a match - return it.
3064 return osr;
3065 }
3066 } else {
3067 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3068 if (osr->comp_level() == CompLevel_highest_tier) {
3069 // Found the best possible - return it.
3070 return osr;
3071 }
3072 best = osr;
3073 }
3074 }
3075 }
3076 osr = osr->osr_link();
3077 }
3078 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3079 return best;
3080 }
3081 return NULL;
3082 }
3083
3084 // -----------------------------------------------------------------------------------------------------
3085 // Printing
3086
3087 #ifndef PRODUCT
3088
3089 #define BULLET " - "
3090
3091 static const char* state_names[] = {
3092 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3093 };
3094
3095 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3096 for (int i = 0; i < len; i++) {
3097 intptr_t e = start[i];
3098 st->print("%d : " INTPTR_FORMAT, i, e);
3099 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3100 st->print(" ");
3101 ((Metadata*)e)->print_value_on(st);
3102 }
3103 st->cr();
3104 }
3105 }
3106
3107 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3108 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3109 }
3110
3111 void InstanceKlass::print_on(outputStream* st) const {
3112 assert(is_klass(), "must be klass");
3113 Klass::print_on(st);
3114
3115 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3116 st->print(BULLET"klass size: %d", size()); st->cr();
3117 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3118 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3119 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3120 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3121 st->print(BULLET"sub: ");
3122 Klass* sub = subklass();
3123 int n;
3124 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3125 if (n < MaxSubklassPrintSize) {
3126 sub->print_value_on(st);
3127 st->print(" ");
3128 }
3129 }
3130 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3131 st->cr();
3132
3133 if (is_interface()) {
3134 MutexLocker ml(Compile_lock);
3135 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3136 if (nof_implementors() == 1) {
3137 st->print_cr(BULLET"implementor: ");
3138 st->print(" ");
3139 implementor()->print_value_on(st);
3140 st->cr();
3141 }
3142 }
3143
3144 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3145 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3146 if (Verbose || WizardMode) {
3147 Array<Method*>* method_array = methods();
3148 for (int i = 0; i < method_array->length(); i++) {
3149 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3150 }
3151 }
3152 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3153 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3154 if (Verbose && default_methods() != NULL) {
3155 Array<Method*>* method_array = default_methods();
3156 for (int i = 0; i < method_array->length(); i++) {
3157 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3158 }
3159 }
3160 if (default_vtable_indices() != NULL) {
3161 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3162 }
3163 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3164 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3165 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3166 if (class_loader_data() != NULL) {
3167 st->print(BULLET"class loader data: ");
3168 class_loader_data()->print_value_on(st);
3169 st->cr();
3170 }
3171 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3172 if (source_file_name() != NULL) {
3173 st->print(BULLET"source file: ");
3174 source_file_name()->print_value_on(st);
3175 st->cr();
3176 }
3177 if (source_debug_extension() != NULL) {
3178 st->print(BULLET"source debug extension: ");
3179 st->print("%s", source_debug_extension());
3180 st->cr();
3181 }
3182 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3183 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3184 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3185 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3186 {
3187 bool have_pv = false;
3188 // previous versions are linked together through the InstanceKlass
3189 for (InstanceKlass* pv_node = previous_versions();
3190 pv_node != NULL;
3191 pv_node = pv_node->previous_versions()) {
3192 if (!have_pv)
3193 st->print(BULLET"previous version: ");
3194 have_pv = true;
3195 pv_node->constants()->print_value_on(st);
3196 }
3197 if (have_pv) st->cr();
3198 }
3199
3200 if (generic_signature() != NULL) {
3201 st->print(BULLET"generic signature: ");
3202 generic_signature()->print_value_on(st);
3203 st->cr();
3204 }
3205 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3206 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3207 if (java_mirror() != NULL) {
3208 st->print(BULLET"java mirror: ");
3209 java_mirror()->print_value_on(st);
3210 st->cr();
3211 } else {
3212 st->print_cr(BULLET"java mirror: NULL");
3213 }
3214 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3215 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3216 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3217 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3218 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3219 FieldPrinter print_static_field(st);
3220 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3221 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3222 FieldPrinter print_nonstatic_field(st);
3223 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3224 ik->do_nonstatic_fields(&print_nonstatic_field);
3225
3226 st->print(BULLET"non-static oop maps: ");
3227 OopMapBlock* map = start_of_nonstatic_oop_maps();
3228 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3229 while (map < end_map) {
3230 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3231 map++;
3232 }
3233 st->cr();
3234 }
3235
3236 #endif //PRODUCT
3237
3238 void InstanceKlass::print_value_on(outputStream* st) const {
3239 assert(is_klass(), "must be klass");
3240 if (Verbose || WizardMode) access_flags().print_on(st);
3241 name()->print_value_on(st);
3242 }
3243
3244 #ifndef PRODUCT
3245
3246 void FieldPrinter::do_field(fieldDescriptor* fd) {
3247 _st->print(BULLET);
3248 if (_obj == NULL) {
3249 fd->print_on(_st);
3250 _st->cr();
3251 } else {
3252 fd->print_on_for(_st, _obj);
3253 _st->cr();
3254 }
3255 }
3256
3257
3258 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3259 Klass::oop_print_on(obj, st);
3260
3261 if (this == SystemDictionary::String_klass()) {
3262 typeArrayOop value = java_lang_String::value(obj);
3263 juint length = java_lang_String::length(obj);
3264 if (value != NULL &&
3265 value->is_typeArray() &&
3266 length <= (juint) value->length()) {
3267 st->print(BULLET"string: ");
3268 java_lang_String::print(obj, st);
3269 st->cr();
3270 if (!WizardMode) return; // that is enough
3271 }
3272 }
3273
3274 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3275 FieldPrinter print_field(st, obj);
3276 do_nonstatic_fields(&print_field);
3277
3278 if (this == SystemDictionary::Class_klass()) {
3279 st->print(BULLET"signature: ");
3280 java_lang_Class::print_signature(obj, st);
3281 st->cr();
3282 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3283 st->print(BULLET"fake entry for mirror: ");
3284 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3285 st->cr();
3286 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3287 st->print(BULLET"fake entry for array: ");
3288 Metadata::print_value_on_maybe_null(st, array_klass);
3289 st->cr();
3290 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3291 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3292 Klass* real_klass = java_lang_Class::as_Klass(obj);
3293 if (real_klass != NULL && real_klass->is_instance_klass()) {
3294 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3295 }
3296 } else if (this == SystemDictionary::MethodType_klass()) {
3297 st->print(BULLET"signature: ");
3298 java_lang_invoke_MethodType::print_signature(obj, st);
3299 st->cr();
3300 }
3301 }
3302
3303 bool InstanceKlass::verify_itable_index(int i) {
3304 int method_count = klassItable::method_count_for_interface(this);
3305 assert(i >= 0 && i < method_count, "index out of bounds");
3306 return true;
3307 }
3308
3309 #endif //PRODUCT
3310
3311 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3312 st->print("a ");
3313 name()->print_value_on(st);
3314 obj->print_address_on(st);
3315 if (this == SystemDictionary::String_klass()
3316 && java_lang_String::value(obj) != NULL) {
3317 ResourceMark rm;
3318 int len = java_lang_String::length(obj);
3319 int plen = (len < 24 ? len : 12);
3320 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3321 st->print(" = \"%s\"", str);
3322 if (len > plen)
3323 st->print("...[%d]", len);
3324 } else if (this == SystemDictionary::Class_klass()) {
3325 Klass* k = java_lang_Class::as_Klass(obj);
3326 st->print(" = ");
3327 if (k != NULL) {
3328 k->print_value_on(st);
3329 } else {
3330 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3331 st->print("%s", tname ? tname : "type?");
3332 }
3333 } else if (this == SystemDictionary::MethodType_klass()) {
3334 st->print(" = ");
3335 java_lang_invoke_MethodType::print_signature(obj, st);
3336 } else if (java_lang_boxing_object::is_instance(obj)) {
3337 st->print(" = ");
3338 java_lang_boxing_object::print(obj, st);
3339 } else if (this == SystemDictionary::LambdaForm_klass()) {
3340 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3341 if (vmentry != NULL) {
3342 st->print(" => ");
3343 vmentry->print_value_on(st);
3344 }
3345 } else if (this == SystemDictionary::MemberName_klass()) {
3346 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3347 if (vmtarget != NULL) {
3348 st->print(" = ");
3349 vmtarget->print_value_on(st);
3350 } else {
3351 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3352 st->print(".");
3353 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3354 }
3355 }
3356 }
3357
3358 const char* InstanceKlass::internal_name() const {
3359 return external_name();
3360 }
3361
3362 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3363 const char* module_name,
3364 const ClassFileStream* cfs) const {
3365 if (!log_is_enabled(Info, class, load)) {
3366 return;
3367 }
3368
3369 ResourceMark rm;
3370 LogMessage(class, load) msg;
3371 stringStream info_stream;
3372
3373 // Name and class hierarchy info
3374 info_stream.print("%s", external_name());
3375
3376 // Source
3377 if (cfs != NULL) {
3378 if (cfs->source() != NULL) {
3379 if (module_name != NULL) {
3380 if (ClassLoader::is_modules_image(cfs->source())) {
3381 info_stream.print(" source: jrt:/%s", module_name);
3382 } else {
3383 info_stream.print(" source: %s", cfs->source());
3384 }
3385 } else {
3386 info_stream.print(" source: %s", cfs->source());
3387 }
3388 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3389 Thread* THREAD = Thread::current();
3390 Klass* caller =
3391 THREAD->is_Java_thread()
3392 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3393 : NULL;
3394 // caller can be NULL, for example, during a JVMTI VM_Init hook
3395 if (caller != NULL) {
3396 info_stream.print(" source: instance of %s", caller->external_name());
3397 } else {
3398 // source is unknown
3399 }
3400 } else {
3401 oop class_loader = loader_data->class_loader();
3402 info_stream.print(" source: %s", class_loader->klass()->external_name());
3403 }
3404 } else {
3405 info_stream.print(" source: shared objects file");
3406 }
3407
3408 msg.info("%s", info_stream.as_string());
3409
3410 if (log_is_enabled(Debug, class, load)) {
3411 stringStream debug_stream;
3412
3413 // Class hierarchy info
3414 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3415 p2i(this), p2i(superklass()));
3416
3417 // Interfaces
3418 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3419 debug_stream.print(" interfaces:");
3420 int length = local_interfaces()->length();
3421 for (int i = 0; i < length; i++) {
3422 debug_stream.print(" " INTPTR_FORMAT,
3423 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3424 }
3425 }
3426
3427 // Class loader
3428 debug_stream.print(" loader: [");
3429 loader_data->print_value_on(&debug_stream);
3430 debug_stream.print("]");
3431
3432 // Classfile checksum
3433 if (cfs) {
3434 debug_stream.print(" bytes: %d checksum: %08x",
3435 cfs->length(),
3436 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3437 cfs->length()));
3438 }
3439
3440 msg.debug("%s", debug_stream.as_string());
3441 }
3442 }
3443
3444 #if INCLUDE_SERVICES
3445 // Size Statistics
3446 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3447 Klass::collect_statistics(sz);
3448
3449 sz->_inst_size = wordSize * size_helper();
3450 sz->_vtab_bytes = wordSize * vtable_length();
3451 sz->_itab_bytes = wordSize * itable_length();
3452 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3453
3454 int n = 0;
3455 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3456 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3457 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3458 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3459 n += (sz->_fields_bytes = sz->count_array(fields()));
3460 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3461 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3462 sz->_ro_bytes += n;
3463
3464 const ConstantPool* cp = constants();
3465 if (cp) {
3466 cp->collect_statistics(sz);
3467 }
3468
3469 const Annotations* anno = annotations();
3470 if (anno) {
3471 anno->collect_statistics(sz);
3472 }
3473
3474 const Array<Method*>* methods_array = methods();
3475 if (methods()) {
3476 for (int i = 0; i < methods_array->length(); i++) {
3477 Method* method = methods_array->at(i);
3478 if (method) {
3479 sz->_method_count ++;
3480 method->collect_statistics(sz);
3481 }
3482 }
3483 }
3484 }
3485 #endif // INCLUDE_SERVICES
3486
3487 // Verification
3488
3489 class VerifyFieldClosure: public BasicOopIterateClosure {
3490 protected:
3491 template <class T> void do_oop_work(T* p) {
3492 oop obj = RawAccess<>::oop_load(p);
3493 if (!oopDesc::is_oop_or_null(obj)) {
3494 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3495 Universe::print_on(tty);
3496 guarantee(false, "boom");
3497 }
3498 }
3499 public:
3500 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3501 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3502 };
3503
3504 void InstanceKlass::verify_on(outputStream* st) {
3505 #ifndef PRODUCT
3506 // Avoid redundant verifies, this really should be in product.
3507 if (_verify_count == Universe::verify_count()) return;
3508 _verify_count = Universe::verify_count();
3509 #endif
3510
3511 // Verify Klass
3512 Klass::verify_on(st);
3513
3514 // Verify that klass is present in ClassLoaderData
3515 guarantee(class_loader_data()->contains_klass(this),
3516 "this class isn't found in class loader data");
3517
3518 // Verify vtables
3519 if (is_linked()) {
3520 // $$$ This used to be done only for m/s collections. Doing it
3521 // always seemed a valid generalization. (DLD -- 6/00)
3522 vtable().verify(st);
3523 }
3524
3525 // Verify first subklass
3526 if (subklass() != NULL) {
3527 guarantee(subklass()->is_klass(), "should be klass");
3528 }
3529
3530 // Verify siblings
3531 Klass* super = this->super();
3532 Klass* sib = next_sibling();
3533 if (sib != NULL) {
3534 if (sib == this) {
3535 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3536 }
3537
3538 guarantee(sib->is_klass(), "should be klass");
3539 guarantee(sib->super() == super, "siblings should have same superklass");
3540 }
3541
3542 // Verify implementor fields requires the Compile_lock, but this is sometimes
3543 // called inside a safepoint, so don't verify.
3544
3545 // Verify local interfaces
3546 if (local_interfaces()) {
3547 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3548 for (int j = 0; j < local_interfaces->length(); j++) {
3549 InstanceKlass* e = local_interfaces->at(j);
3550 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3551 }
3552 }
3553
3554 // Verify transitive interfaces
3555 if (transitive_interfaces() != NULL) {
3556 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3557 for (int j = 0; j < transitive_interfaces->length(); j++) {
3558 InstanceKlass* e = transitive_interfaces->at(j);
3559 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3560 }
3561 }
3562
3563 // Verify methods
3564 if (methods() != NULL) {
3565 Array<Method*>* methods = this->methods();
3566 for (int j = 0; j < methods->length(); j++) {
3567 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3568 }
3569 for (int j = 0; j < methods->length() - 1; j++) {
3570 Method* m1 = methods->at(j);
3571 Method* m2 = methods->at(j + 1);
3572 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3573 }
3574 }
3575
3576 // Verify method ordering
3577 if (method_ordering() != NULL) {
3578 Array<int>* method_ordering = this->method_ordering();
3579 int length = method_ordering->length();
3580 if (JvmtiExport::can_maintain_original_method_order() ||
3581 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3582 guarantee(length == methods()->length(), "invalid method ordering length");
3583 jlong sum = 0;
3584 for (int j = 0; j < length; j++) {
3585 int original_index = method_ordering->at(j);
3586 guarantee(original_index >= 0, "invalid method ordering index");
3587 guarantee(original_index < length, "invalid method ordering index");
3588 sum += original_index;
3589 }
3590 // Verify sum of indices 0,1,...,length-1
3591 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3592 } else {
3593 guarantee(length == 0, "invalid method ordering length");
3594 }
3595 }
3596
3597 // Verify default methods
3598 if (default_methods() != NULL) {
3599 Array<Method*>* methods = this->default_methods();
3600 for (int j = 0; j < methods->length(); j++) {
3601 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3602 }
3603 for (int j = 0; j < methods->length() - 1; j++) {
3604 Method* m1 = methods->at(j);
3605 Method* m2 = methods->at(j + 1);
3606 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3607 }
3608 }
3609
3610 // Verify JNI static field identifiers
3611 if (jni_ids() != NULL) {
3612 jni_ids()->verify(this);
3613 }
3614
3615 // Verify other fields
3616 if (array_klasses() != NULL) {
3617 guarantee(array_klasses()->is_klass(), "should be klass");
3618 }
3619 if (constants() != NULL) {
3620 guarantee(constants()->is_constantPool(), "should be constant pool");
3621 }
3622 const Klass* anonymous_host = unsafe_anonymous_host();
3623 if (anonymous_host != NULL) {
3624 guarantee(anonymous_host->is_klass(), "should be klass");
3625 }
3626 }
3627
3628 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3629 Klass::oop_verify_on(obj, st);
3630 VerifyFieldClosure blk;
3631 obj->oop_iterate(&blk);
3632 }
3633
3634
3635 // JNIid class for jfieldIDs only
3636 // Note to reviewers:
3637 // These JNI functions are just moved over to column 1 and not changed
3638 // in the compressed oops workspace.
3639 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3640 _holder = holder;
3641 _offset = offset;
3642 _next = next;
3643 debug_only(_is_static_field_id = false;)
3644 }
3645
3646
3647 JNIid* JNIid::find(int offset) {
3648 JNIid* current = this;
3649 while (current != NULL) {
3650 if (current->offset() == offset) return current;
3651 current = current->next();
3652 }
3653 return NULL;
3654 }
3655
3656 void JNIid::deallocate(JNIid* current) {
3657 while (current != NULL) {
3658 JNIid* next = current->next();
3659 delete current;
3660 current = next;
3661 }
3662 }
3663
3664
3665 void JNIid::verify(Klass* holder) {
3666 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3667 int end_field_offset;
3668 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3669
3670 JNIid* current = this;
3671 while (current != NULL) {
3672 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3673 #ifdef ASSERT
3674 int o = current->offset();
3675 if (current->is_static_field_id()) {
3676 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3677 }
3678 #endif
3679 current = current->next();
3680 }
3681 }
3682
3683 #ifdef ASSERT
3684 void InstanceKlass::set_init_state(ClassState state) {
3685 bool good_state = is_shared() ? (_init_state <= state)
3686 : (_init_state < state);
3687 assert(good_state || state == allocated, "illegal state transition");
3688 _init_state = (u1)state;
3689 }
3690 #endif
3691
3692 #if INCLUDE_JVMTI
3693
3694 // RedefineClasses() support for previous versions
3695
3696 // Globally, there is at least one previous version of a class to walk
3697 // during class unloading, which is saved because old methods in the class
3698 // are still running. Otherwise the previous version list is cleaned up.
3699 bool InstanceKlass::_has_previous_versions = false;
3700
3701 // Returns true if there are previous versions of a class for class
3702 // unloading only. Also resets the flag to false. purge_previous_version
3703 // will set the flag to true if there are any left, i.e., if there's any
3704 // work to do for next time. This is to avoid the expensive code cache
3705 // walk in CLDG::clean_deallocate_lists().
3706 bool InstanceKlass::has_previous_versions_and_reset() {
3707 bool ret = _has_previous_versions;
3708 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3709 ret ? "true" : "false");
3710 _has_previous_versions = false;
3711 return ret;
3712 }
3713
3714 // Purge previous versions before adding new previous versions of the class and
3715 // during class unloading.
3716 void InstanceKlass::purge_previous_version_list() {
3717 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3718 assert(has_been_redefined(), "Should only be called for main class");
3719
3720 // Quick exit.
3721 if (previous_versions() == NULL) {
3722 return;
3723 }
3724
3725 // This klass has previous versions so see what we can cleanup
3726 // while it is safe to do so.
3727
3728 int deleted_count = 0; // leave debugging breadcrumbs
3729 int live_count = 0;
3730 ClassLoaderData* loader_data = class_loader_data();
3731 assert(loader_data != NULL, "should never be null");
3732
3733 ResourceMark rm;
3734 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3735
3736 // previous versions are linked together through the InstanceKlass
3737 InstanceKlass* pv_node = previous_versions();
3738 InstanceKlass* last = this;
3739 int version = 0;
3740
3741 // check the previous versions list
3742 for (; pv_node != NULL; ) {
3743
3744 ConstantPool* pvcp = pv_node->constants();
3745 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3746
3747 if (!pvcp->on_stack()) {
3748 // If the constant pool isn't on stack, none of the methods
3749 // are executing. Unlink this previous_version.
3750 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3751 // so will be deallocated during the next phase of class unloading.
3752 log_trace(redefine, class, iklass, purge)
3753 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3754 // For debugging purposes.
3755 pv_node->set_is_scratch_class();
3756 // Unlink from previous version list.
3757 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3758 InstanceKlass* next = pv_node->previous_versions();
3759 pv_node->link_previous_versions(NULL); // point next to NULL
3760 last->link_previous_versions(next);
3761 // Add to the deallocate list after unlinking
3762 loader_data->add_to_deallocate_list(pv_node);
3763 pv_node = next;
3764 deleted_count++;
3765 version++;
3766 continue;
3767 } else {
3768 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3769 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3770 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3771 live_count++;
3772 // found a previous version for next time we do class unloading
3773 _has_previous_versions = true;
3774 }
3775
3776 // At least one method is live in this previous version.
3777 // Reset dead EMCP methods not to get breakpoints.
3778 // All methods are deallocated when all of the methods for this class are no
3779 // longer running.
3780 Array<Method*>* method_refs = pv_node->methods();
3781 if (method_refs != NULL) {
3782 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3783 for (int j = 0; j < method_refs->length(); j++) {
3784 Method* method = method_refs->at(j);
3785
3786 if (!method->on_stack()) {
3787 // no breakpoints for non-running methods
3788 if (method->is_running_emcp()) {
3789 method->set_running_emcp(false);
3790 }
3791 } else {
3792 assert (method->is_obsolete() || method->is_running_emcp(),
3793 "emcp method cannot run after emcp bit is cleared");
3794 log_trace(redefine, class, iklass, purge)
3795 ("purge: %s(%s): prev method @%d in version @%d is alive",
3796 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3797 }
3798 }
3799 }
3800 // next previous version
3801 last = pv_node;
3802 pv_node = pv_node->previous_versions();
3803 version++;
3804 }
3805 log_trace(redefine, class, iklass, purge)
3806 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3807 }
3808
3809 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3810 int emcp_method_count) {
3811 int obsolete_method_count = old_methods->length() - emcp_method_count;
3812
3813 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3814 _previous_versions != NULL) {
3815 // We have a mix of obsolete and EMCP methods so we have to
3816 // clear out any matching EMCP method entries the hard way.
3817 int local_count = 0;
3818 for (int i = 0; i < old_methods->length(); i++) {
3819 Method* old_method = old_methods->at(i);
3820 if (old_method->is_obsolete()) {
3821 // only obsolete methods are interesting
3822 Symbol* m_name = old_method->name();
3823 Symbol* m_signature = old_method->signature();
3824
3825 // previous versions are linked together through the InstanceKlass
3826 int j = 0;
3827 for (InstanceKlass* prev_version = _previous_versions;
3828 prev_version != NULL;
3829 prev_version = prev_version->previous_versions(), j++) {
3830
3831 Array<Method*>* method_refs = prev_version->methods();
3832 for (int k = 0; k < method_refs->length(); k++) {
3833 Method* method = method_refs->at(k);
3834
3835 if (!method->is_obsolete() &&
3836 method->name() == m_name &&
3837 method->signature() == m_signature) {
3838 // The current RedefineClasses() call has made all EMCP
3839 // versions of this method obsolete so mark it as obsolete
3840 log_trace(redefine, class, iklass, add)
3841 ("%s(%s): flush obsolete method @%d in version @%d",
3842 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3843
3844 method->set_is_obsolete();
3845 break;
3846 }
3847 }
3848
3849 // The previous loop may not find a matching EMCP method, but
3850 // that doesn't mean that we can optimize and not go any
3851 // further back in the PreviousVersion generations. The EMCP
3852 // method for this generation could have already been made obsolete,
3853 // but there still may be an older EMCP method that has not
3854 // been made obsolete.
3855 }
3856
3857 if (++local_count >= obsolete_method_count) {
3858 // no more obsolete methods so bail out now
3859 break;
3860 }
3861 }
3862 }
3863 }
3864 }
3865
3866 // Save the scratch_class as the previous version if any of the methods are running.
3867 // The previous_versions are used to set breakpoints in EMCP methods and they are
3868 // also used to clean MethodData links to redefined methods that are no longer running.
3869 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3870 int emcp_method_count) {
3871 assert(Thread::current()->is_VM_thread(),
3872 "only VMThread can add previous versions");
3873
3874 ResourceMark rm;
3875 log_trace(redefine, class, iklass, add)
3876 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3877
3878 // Clean out old previous versions for this class
3879 purge_previous_version_list();
3880
3881 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3882 // a previous redefinition may be made obsolete by this redefinition.
3883 Array<Method*>* old_methods = scratch_class->methods();
3884 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3885
3886 // If the constant pool for this previous version of the class
3887 // is not marked as being on the stack, then none of the methods
3888 // in this previous version of the class are on the stack so
3889 // we don't need to add this as a previous version.
3890 ConstantPool* cp_ref = scratch_class->constants();
3891 if (!cp_ref->on_stack()) {
3892 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3893 // For debugging purposes.
3894 scratch_class->set_is_scratch_class();
3895 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3896 return;
3897 }
3898
3899 if (emcp_method_count != 0) {
3900 // At least one method is still running, check for EMCP methods
3901 for (int i = 0; i < old_methods->length(); i++) {
3902 Method* old_method = old_methods->at(i);
3903 if (!old_method->is_obsolete() && old_method->on_stack()) {
3904 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3905 // we can add breakpoints for it.
3906
3907 // We set the method->on_stack bit during safepoints for class redefinition
3908 // and use this bit to set the is_running_emcp bit.
3909 // After the safepoint, the on_stack bit is cleared and the running emcp
3910 // method may exit. If so, we would set a breakpoint in a method that
3911 // is never reached, but this won't be noticeable to the programmer.
3912 old_method->set_running_emcp(true);
3913 log_trace(redefine, class, iklass, add)
3914 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3915 } else if (!old_method->is_obsolete()) {
3916 log_trace(redefine, class, iklass, add)
3917 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3918 }
3919 }
3920 }
3921
3922 // Add previous version if any methods are still running.
3923 // Set has_previous_version flag for processing during class unloading.
3924 _has_previous_versions = true;
3925 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3926 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3927 scratch_class->link_previous_versions(previous_versions());
3928 link_previous_versions(scratch_class);
3929 } // end add_previous_version()
3930
3931 #endif // INCLUDE_JVMTI
3932
3933 Method* InstanceKlass::method_with_idnum(int idnum) {
3934 Method* m = NULL;
3935 if (idnum < methods()->length()) {
3936 m = methods()->at(idnum);
3937 }
3938 if (m == NULL || m->method_idnum() != idnum) {
3939 for (int index = 0; index < methods()->length(); ++index) {
3940 m = methods()->at(index);
3941 if (m->method_idnum() == idnum) {
3942 return m;
3943 }
3944 }
3945 // None found, return null for the caller to handle.
3946 return NULL;
3947 }
3948 return m;
3949 }
3950
3951
3952 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3953 if (idnum >= methods()->length()) {
3954 return NULL;
3955 }
3956 Method* m = methods()->at(idnum);
3957 if (m != NULL && m->orig_method_idnum() == idnum) {
3958 return m;
3959 }
3960 // Obsolete method idnum does not match the original idnum
3961 for (int index = 0; index < methods()->length(); ++index) {
3962 m = methods()->at(index);
3963 if (m->orig_method_idnum() == idnum) {
3964 return m;
3965 }
3966 }
3967 // None found, return null for the caller to handle.
3968 return NULL;
3969 }
3970
3971
3972 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3973 InstanceKlass* holder = get_klass_version(version);
3974 if (holder == NULL) {
3975 return NULL; // The version of klass is gone, no method is found
3976 }
3977 Method* method = holder->method_with_orig_idnum(idnum);
3978 return method;
3979 }
3980
3981 #if INCLUDE_JVMTI
3982 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3983 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3984 // Ignore the archived class stream data
3985 return NULL;
3986 } else {
3987 return _cached_class_file;
3988 }
3989 }
3990
3991 jint InstanceKlass::get_cached_class_file_len() {
3992 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3993 }
3994
3995 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3996 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3997 }
3998
3999 #if INCLUDE_CDS
4000 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
4001 if (DumpSharedSpaces) {
4002 return _cached_class_file;
4003 } else {
4004 assert(this->is_shared(), "class should be shared");
4005 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
4006 return _cached_class_file;
4007 } else {
4008 return NULL;
4009 }
4010 }
4011 }
4012 #endif
4013 #endif