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 for a resolved cp entry , else fall back to a name check.
169 // We don't want to resolve any class other than the one being checked.
170 for (int i = 0; i < _nest_members->length(); i++) {
171 int cp_index = _nest_members->at(i);
172 if (_constants->tag_at(cp_index).is_klass()) {
173 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
174 if (k2 == k) {
175 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
176 return true;
177 }
178 }
179 else {
180 Symbol* name = _constants->klass_name_at(cp_index);
181 if (name == k->name()) {
182 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
183
184 // names match so check actual klass - this may trigger class loading if
185 // it doesn't match (but that should be impossible)
186 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
187 if (k2 == k) {
188 log_trace(class, nestmates)("- class is listed as a nest member");
189 return true;
190 }
191 else {
192 // same name but different klass!
193 log_trace(class, nestmates)(" - klass comparison failed!");
194 // can't have two names the same, so we're done
195 return false;
196 }
197 }
198 }
199 }
200 log_trace(class, nestmates)("- class is NOT a nest member!");
201 return false;
202 }
203
204 // Return nest-host class, resolving, validating and saving it if needed.
205 // In cases where this is called from a thread that can not do classloading
206 // (such as a native JIT thread) then we simply return NULL, which in turn
207 // causes the access check to return false. Such code will retry the access
208 // from a more suitable environment later.
209 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
210 InstanceKlass* nest_host_k = _nest_host;
211 if (nest_host_k == NULL) {
212 // need to resolve and save our nest-host class. This could be attempted
213 // concurrently but as the result is idempotent and we don't use the class
214 // then we do not need any synchronization beyond what is implicitly used
215 // during class loading.
216 if (_nest_host_index != 0) { // we have a real nest_host
217 // Before trying to resolve check if we're in a suitable context
218 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
219 if (log_is_enabled(Trace, class, nestmates)) {
220 ResourceMark rm(THREAD);
221 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
222 this->external_name());
223 }
224 return NULL;
225 }
226
227 if (log_is_enabled(Trace, class, nestmates)) {
228 ResourceMark rm(THREAD);
229 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
230 this->external_name(),
231 _constants->klass_name_at(_nest_host_index)->as_C_string());
232 }
233
234 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
235 if (HAS_PENDING_EXCEPTION) {
236 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
237 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
238 // throw a new CDNFE with the original as its cause, and a clear msg
239 ResourceMark rm(THREAD);
240 char buf[200];
241 CLEAR_PENDING_EXCEPTION;
242 jio_snprintf(buf, sizeof(buf),
243 "Unable to load nest-host class (%s) of %s",
244 _constants->klass_name_at(_nest_host_index)->as_C_string(),
245 this->external_name());
246 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
247 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
248 }
249 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
250 return NULL;
251 }
252
253 // A valid nest-host is an instance class in the current package that lists this
254 // class as a nest member. If any of these conditions are not met we post the
255 // requested exception type (if any) and return NULL
256
257 const char* error = NULL;
258
259 // JVMS 5.4.4 indicates package check comes first
260 if (is_same_class_package(k)) {
261
262 // Now check actual membership. We can't be a member if our "host" is
263 // not an instance class.
264 if (k->is_instance_klass()) {
265 nest_host_k = InstanceKlass::cast(k);
266
267 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
268 if (is_member) {
269 // save resolved nest-host value
270 _nest_host = nest_host_k;
271
272 if (log_is_enabled(Trace, class, nestmates)) {
273 ResourceMark rm(THREAD);
274 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
275 this->external_name(), k->external_name());
276 }
277 return nest_host_k;
278 }
279 }
280 error = "current type is not listed as a nest member";
281 } else {
282 error = "types are in different packages";
283 }
284
285 if (log_is_enabled(Trace, class, nestmates)) {
286 ResourceMark rm(THREAD);
287 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
288 this->external_name(),
289 k->external_name(),
290 error);
291 }
292
293 if (validationException != NULL) {
294 ResourceMark rm(THREAD);
295 Exceptions::fthrow(THREAD_AND_LOCATION,
296 validationException,
297 "Type %s is not a nest member of %s: %s",
298 this->external_name(),
299 k->external_name(),
300 error
301 );
302 }
303 return NULL;
304 } else {
305 if (log_is_enabled(Trace, class, nestmates)) {
306 ResourceMark rm(THREAD);
307 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
308 this->external_name());
309 }
310 // save resolved nest-host value
311 return (_nest_host = this);
312 }
313 }
314 return nest_host_k;
315 }
316
317 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
318 // or we are k's nest_host - all of which is covered by comparing the two
319 // resolved_nest_hosts
320 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
321
322 assert(this != k, "this should be handled by higher-level code");
323
324 // Per JVMS 5.4.4 we first resolve and validate the current class, then
325 // the target class k. Resolution exceptions will be passed on by upper
326 // layers. IncompatibleClassChangeErrors from membership validation failures
327 // will also be passed through.
328
329 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
330 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
331 if (cur_host == NULL) {
332 return false;
333 }
334
335 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
336 if (k_nest_host == NULL) {
337 return false;
338 }
339
340 bool access = (cur_host == k_nest_host);
341
342 if (log_is_enabled(Trace, class, nestmates)) {
343 ResourceMark rm(THREAD);
344 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
345 this->external_name(),
346 access ? "" : "NOT ",
347 k->external_name());
348 }
349
350 return access;
351 }
352
353 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
354 const int size = InstanceKlass::size(parser.vtable_size(),
355 parser.itable_size(),
356 nonstatic_oop_map_size(parser.total_oop_map_count()),
357 parser.is_interface(),
358 parser.is_unsafe_anonymous(),
359 should_store_fingerprint(parser.is_unsafe_anonymous()));
360
361 const Symbol* const class_name = parser.class_name();
362 assert(class_name != NULL, "invariant");
363 ClassLoaderData* loader_data = parser.loader_data();
364 assert(loader_data != NULL, "invariant");
365
366 InstanceKlass* ik;
367
368 // Allocation
369 if (REF_NONE == parser.reference_type()) {
370 if (class_name == vmSymbols::java_lang_Class()) {
371 // mirror
372 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
373 }
374 else if (is_class_loader(class_name, parser)) {
375 // class loader
376 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
377 } else {
378 // normal
379 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
380 }
381 } else {
382 // reference
383 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
384 }
385
386 // Check for pending exception before adding to the loader data and incrementing
387 // class count. Can get OOM here.
388 if (HAS_PENDING_EXCEPTION) {
389 return NULL;
390 }
391
392 return ik;
393 }
394
395
396 // copy method ordering from resource area to Metaspace
397 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
398 if (m != NULL) {
399 // allocate a new array and copy contents (memcpy?)
400 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
401 for (int i = 0; i < m->length(); i++) {
402 _method_ordering->at_put(i, m->at(i));
403 }
404 } else {
405 _method_ordering = Universe::the_empty_int_array();
406 }
407 }
408
409 // create a new array of vtable_indices for default methods
410 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
411 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
412 assert(default_vtable_indices() == NULL, "only create once");
413 set_default_vtable_indices(vtable_indices);
414 return vtable_indices;
415 }
416
417 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
418 Klass(id),
419 _nest_members(NULL),
420 _nest_host_index(0),
421 _nest_host(NULL),
422 _static_field_size(parser.static_field_size()),
423 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
424 _itable_len(parser.itable_size()),
425 _reference_type(parser.reference_type()) {
426 set_vtable_length(parser.vtable_size());
427 set_kind(kind);
428 set_access_flags(parser.access_flags());
429 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
430 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
431 false));
432
433 assert(NULL == _methods, "underlying memory not zeroed?");
434 assert(is_instance_klass(), "is layout incorrect?");
435 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
436 }
437
438 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
439 Array<Method*>* methods) {
440 if (methods != NULL && methods != Universe::the_empty_method_array() &&
441 !methods->is_shared()) {
442 for (int i = 0; i < methods->length(); i++) {
443 Method* method = methods->at(i);
444 if (method == NULL) continue; // maybe null if error processing
445 // Only want to delete methods that are not executing for RedefineClasses.
446 // The previous version will point to them so they're not totally dangling
447 assert (!method->on_stack(), "shouldn't be called with methods on stack");
448 MetadataFactory::free_metadata(loader_data, method);
449 }
450 MetadataFactory::free_array<Method*>(loader_data, methods);
451 }
452 }
453
454 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
455 const Klass* super_klass,
456 Array<InstanceKlass*>* local_interfaces,
457 Array<InstanceKlass*>* transitive_interfaces) {
458 // Only deallocate transitive interfaces if not empty, same as super class
459 // or same as local interfaces. See code in parseClassFile.
460 Array<InstanceKlass*>* ti = transitive_interfaces;
461 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
462 // check that the interfaces don't come from super class
463 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
464 InstanceKlass::cast(super_klass)->transitive_interfaces();
465 if (ti != sti && ti != NULL && !ti->is_shared()) {
466 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
467 }
468 }
469
470 // local interfaces can be empty
471 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
472 local_interfaces != NULL && !local_interfaces->is_shared()) {
473 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
474 }
475 }
476
477 // This function deallocates the metadata and C heap pointers that the
478 // InstanceKlass points to.
479 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
480
481 // Orphan the mirror first, CMS thinks it's still live.
482 if (java_mirror() != NULL) {
483 java_lang_Class::set_klass(java_mirror(), NULL);
484 }
485
486 // Also remove mirror from handles
487 loader_data->remove_handle(_java_mirror);
488
489 // Need to take this class off the class loader data list.
490 loader_data->remove_class(this);
491
492 // The array_klass for this class is created later, after error handling.
493 // For class redefinition, we keep the original class so this scratch class
494 // doesn't have an array class. Either way, assert that there is nothing
495 // to deallocate.
496 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
497
498 // Release C heap allocated data that this might point to, which includes
499 // reference counting symbol names.
500 release_C_heap_structures();
501
502 deallocate_methods(loader_data, methods());
503 set_methods(NULL);
504
505 if (method_ordering() != NULL &&
506 method_ordering() != Universe::the_empty_int_array() &&
507 !method_ordering()->is_shared()) {
508 MetadataFactory::free_array<int>(loader_data, method_ordering());
509 }
510 set_method_ordering(NULL);
511
512 // default methods can be empty
513 if (default_methods() != NULL &&
514 default_methods() != Universe::the_empty_method_array() &&
515 !default_methods()->is_shared()) {
516 MetadataFactory::free_array<Method*>(loader_data, default_methods());
517 }
518 // Do NOT deallocate the default methods, they are owned by superinterfaces.
519 set_default_methods(NULL);
520
521 // default methods vtable indices can be empty
522 if (default_vtable_indices() != NULL &&
523 !default_vtable_indices()->is_shared()) {
524 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
525 }
526 set_default_vtable_indices(NULL);
527
528
529 // This array is in Klass, but remove it with the InstanceKlass since
530 // this place would be the only caller and it can share memory with transitive
531 // interfaces.
532 if (secondary_supers() != NULL &&
533 secondary_supers() != Universe::the_empty_klass_array() &&
534 // see comments in compute_secondary_supers about the following cast
535 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
536 !secondary_supers()->is_shared()) {
537 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
538 }
539 set_secondary_supers(NULL);
540
541 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
542 set_transitive_interfaces(NULL);
543 set_local_interfaces(NULL);
544
545 if (fields() != NULL && !fields()->is_shared()) {
546 MetadataFactory::free_array<jushort>(loader_data, fields());
547 }
548 set_fields(NULL, 0);
549
550 // If a method from a redefined class is using this constant pool, don't
551 // delete it, yet. The new class's previous version will point to this.
552 if (constants() != NULL) {
553 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
554 if (!constants()->is_shared()) {
555 MetadataFactory::free_metadata(loader_data, constants());
556 }
557 // Delete any cached resolution errors for the constant pool
558 SystemDictionary::delete_resolution_error(constants());
559
560 set_constants(NULL);
561 }
562
563 if (inner_classes() != NULL &&
564 inner_classes() != Universe::the_empty_short_array() &&
565 !inner_classes()->is_shared()) {
566 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
567 }
568 set_inner_classes(NULL);
569
570 if (nest_members() != NULL &&
571 nest_members() != Universe::the_empty_short_array() &&
572 !nest_members()->is_shared()) {
573 MetadataFactory::free_array<jushort>(loader_data, nest_members());
574 }
575 set_nest_members(NULL);
576
577 // We should deallocate the Annotations instance if it's not in shared spaces.
578 if (annotations() != NULL && !annotations()->is_shared()) {
579 MetadataFactory::free_metadata(loader_data, annotations());
580 }
581 set_annotations(NULL);
582 }
583
584 bool InstanceKlass::should_be_initialized() const {
585 return !is_initialized();
586 }
587
588 klassItable InstanceKlass::itable() const {
589 return klassItable(const_cast<InstanceKlass*>(this));
590 }
591
592 void InstanceKlass::eager_initialize(Thread *thread) {
593 if (!EagerInitialization) return;
594
595 if (this->is_not_initialized()) {
596 // abort if the the class has a class initializer
597 if (this->class_initializer() != NULL) return;
598
599 // abort if it is java.lang.Object (initialization is handled in genesis)
600 Klass* super_klass = super();
601 if (super_klass == NULL) return;
602
603 // abort if the super class should be initialized
604 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
605
606 // call body to expose the this pointer
607 eager_initialize_impl();
608 }
609 }
610
611 // JVMTI spec thinks there are signers and protection domain in the
612 // instanceKlass. These accessors pretend these fields are there.
613 // The hprof specification also thinks these fields are in InstanceKlass.
614 oop InstanceKlass::protection_domain() const {
615 // return the protection_domain from the mirror
616 return java_lang_Class::protection_domain(java_mirror());
617 }
618
619 // To remove these from requires an incompatible change and CCC request.
620 objArrayOop InstanceKlass::signers() const {
621 // return the signers from the mirror
622 return java_lang_Class::signers(java_mirror());
623 }
624
625 oop InstanceKlass::init_lock() const {
626 // return the init lock from the mirror
627 oop lock = java_lang_Class::init_lock(java_mirror());
628 // Prevent reordering with any access of initialization state
629 OrderAccess::loadload();
630 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
631 "only fully initialized state can have a null lock");
632 return lock;
633 }
634
635 // Set the initialization lock to null so the object can be GC'ed. Any racing
636 // threads to get this lock will see a null lock and will not lock.
637 // That's okay because they all check for initialized state after getting
638 // the lock and return.
639 void InstanceKlass::fence_and_clear_init_lock() {
640 // make sure previous stores are all done, notably the init_state.
641 OrderAccess::storestore();
642 java_lang_Class::set_init_lock(java_mirror(), NULL);
643 assert(!is_not_initialized(), "class must be initialized now");
644 }
645
646 void InstanceKlass::eager_initialize_impl() {
647 EXCEPTION_MARK;
648 HandleMark hm(THREAD);
649 Handle h_init_lock(THREAD, init_lock());
650 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
651
652 // abort if someone beat us to the initialization
653 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
654
655 ClassState old_state = init_state();
656 link_class_impl(THREAD);
657 if (HAS_PENDING_EXCEPTION) {
658 CLEAR_PENDING_EXCEPTION;
659 // Abort if linking the class throws an exception.
660
661 // Use a test to avoid redundantly resetting the state if there's
662 // no change. Set_init_state() asserts that state changes make
663 // progress, whereas here we might just be spinning in place.
664 if (old_state != _init_state)
665 set_init_state(old_state);
666 } else {
667 // linking successfull, mark class as initialized
668 set_init_state(fully_initialized);
669 fence_and_clear_init_lock();
670 // trace
671 if (log_is_enabled(Info, class, init)) {
672 ResourceMark rm(THREAD);
673 log_info(class, init)("[Initialized %s without side effects]", external_name());
674 }
675 }
676 }
677
678
679 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
680 // process. The step comments refers to the procedure described in that section.
681 // Note: implementation moved to static method to expose the this pointer.
682 void InstanceKlass::initialize(TRAPS) {
683 if (this->should_be_initialized()) {
684 initialize_impl(CHECK);
685 // Note: at this point the class may be initialized
686 // OR it may be in the state of being initialized
687 // in case of recursive initialization!
688 } else {
689 assert(is_initialized(), "sanity check");
690 }
691 }
692
693
694 bool InstanceKlass::verify_code(TRAPS) {
695 // 1) Verify the bytecodes
696 return Verifier::verify(this, should_verify_class(), THREAD);
697 }
698
699 void InstanceKlass::link_class(TRAPS) {
700 assert(is_loaded(), "must be loaded");
701 if (!is_linked()) {
702 link_class_impl(CHECK);
703 }
704 }
705
706 // Called to verify that a class can link during initialization, without
707 // throwing a VerifyError.
708 bool InstanceKlass::link_class_or_fail(TRAPS) {
709 assert(is_loaded(), "must be loaded");
710 if (!is_linked()) {
711 link_class_impl(CHECK_false);
712 }
713 return is_linked();
714 }
715
716 bool InstanceKlass::link_class_impl(TRAPS) {
717 if (DumpSharedSpaces && is_in_error_state()) {
718 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
719 // the class has failed verification. Throwing the NoClassDefFoundError here is just
720 // a convenient way to stop repeat attempts to verify the same (bad) class.
721 //
722 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
723 // if we are executing Java code. This is not a problem for CDS dumping phase since
724 // it doesn't execute any Java code.
725 ResourceMark rm(THREAD);
726 Exceptions::fthrow(THREAD_AND_LOCATION,
727 vmSymbols::java_lang_NoClassDefFoundError(),
728 "Class %s, or one of its supertypes, failed class initialization",
729 external_name());
730 return false;
731 }
732 // return if already verified
733 if (is_linked()) {
734 return true;
735 }
736
737 // Timing
738 // timer handles recursion
739 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
740 JavaThread* jt = (JavaThread*)THREAD;
741
742 // link super class before linking this class
743 Klass* super_klass = super();
744 if (super_klass != NULL) {
745 if (super_klass->is_interface()) { // check if super class is an interface
746 ResourceMark rm(THREAD);
747 Exceptions::fthrow(
748 THREAD_AND_LOCATION,
749 vmSymbols::java_lang_IncompatibleClassChangeError(),
750 "class %s has interface %s as super class",
751 external_name(),
752 super_klass->external_name()
753 );
754 return false;
755 }
756
757 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
758 ik_super->link_class_impl(CHECK_false);
759 }
760
761 // link all interfaces implemented by this class before linking this class
762 Array<InstanceKlass*>* interfaces = local_interfaces();
763 int num_interfaces = interfaces->length();
764 for (int index = 0; index < num_interfaces; index++) {
765 InstanceKlass* interk = interfaces->at(index);
766 interk->link_class_impl(CHECK_false);
767 }
768
769 // in case the class is linked in the process of linking its superclasses
770 if (is_linked()) {
771 return true;
772 }
773
774 // trace only the link time for this klass that includes
775 // the verification time
776 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
777 ClassLoader::perf_class_link_selftime(),
778 ClassLoader::perf_classes_linked(),
779 jt->get_thread_stat()->perf_recursion_counts_addr(),
780 jt->get_thread_stat()->perf_timers_addr(),
781 PerfClassTraceTime::CLASS_LINK);
782
783 // verification & rewriting
784 {
785 HandleMark hm(THREAD);
786 Handle h_init_lock(THREAD, init_lock());
787 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
788 // rewritten will have been set if loader constraint error found
789 // on an earlier link attempt
790 // don't verify or rewrite if already rewritten
791 //
792
793 if (!is_linked()) {
794 if (!is_rewritten()) {
795 {
796 bool verify_ok = verify_code(THREAD);
797 if (!verify_ok) {
798 return false;
799 }
800 }
801
802 // Just in case a side-effect of verify linked this class already
803 // (which can sometimes happen since the verifier loads classes
804 // using custom class loaders, which are free to initialize things)
805 if (is_linked()) {
806 return true;
807 }
808
809 // also sets rewritten
810 rewrite_class(CHECK_false);
811 } else if (is_shared()) {
812 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
813 }
814
815 // relocate jsrs and link methods after they are all rewritten
816 link_methods(CHECK_false);
817
818 // Initialize the vtable and interface table after
819 // methods have been rewritten since rewrite may
820 // fabricate new Method*s.
821 // also does loader constraint checking
822 //
823 // initialize_vtable and initialize_itable need to be rerun for
824 // a shared class if the class is not loaded by the NULL classloader.
825 ClassLoaderData * loader_data = class_loader_data();
826 if (!(is_shared() &&
827 loader_data->is_the_null_class_loader_data())) {
828 vtable().initialize_vtable(true, CHECK_false);
829 itable().initialize_itable(true, CHECK_false);
830 }
831 #ifdef ASSERT
832 else {
833 vtable().verify(tty, true);
834 // In case itable verification is ever added.
835 // itable().verify(tty, true);
836 }
837 #endif
838 set_init_state(linked);
839 if (JvmtiExport::should_post_class_prepare()) {
840 Thread *thread = THREAD;
841 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
842 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
843 }
844 }
845 }
846 return true;
847 }
848
849 // Rewrite the byte codes of all of the methods of a class.
850 // The rewriter must be called exactly once. Rewriting must happen after
851 // verification but before the first method of the class is executed.
852 void InstanceKlass::rewrite_class(TRAPS) {
853 assert(is_loaded(), "must be loaded");
854 if (is_rewritten()) {
855 assert(is_shared(), "rewriting an unshared class?");
856 return;
857 }
858 Rewriter::rewrite(this, CHECK);
859 set_rewritten();
860 }
861
862 // Now relocate and link method entry points after class is rewritten.
863 // This is outside is_rewritten flag. In case of an exception, it can be
864 // executed more than once.
865 void InstanceKlass::link_methods(TRAPS) {
866 int len = methods()->length();
867 for (int i = len-1; i >= 0; i--) {
868 methodHandle m(THREAD, methods()->at(i));
869
870 // Set up method entry points for compiler and interpreter .
871 m->link_method(m, CHECK);
872 }
873 }
874
875 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
876 void InstanceKlass::initialize_super_interfaces(TRAPS) {
877 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
878 for (int i = 0; i < local_interfaces()->length(); ++i) {
879 InstanceKlass* ik = local_interfaces()->at(i);
880
881 // Initialization is depth first search ie. we start with top of the inheritance tree
882 // has_nonstatic_concrete_methods drives searching superinterfaces since it
883 // means has_nonstatic_concrete_methods in its superinterface hierarchy
884 if (ik->has_nonstatic_concrete_methods()) {
885 ik->initialize_super_interfaces(CHECK);
886 }
887
888 // Only initialize() interfaces that "declare" concrete methods.
889 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
890 ik->initialize(CHECK);
891 }
892 }
893 }
894
895 void InstanceKlass::initialize_impl(TRAPS) {
896 HandleMark hm(THREAD);
897
898 // Make sure klass is linked (verified) before initialization
899 // A class could already be verified, since it has been reflected upon.
900 link_class(CHECK);
901
902 DTRACE_CLASSINIT_PROBE(required, -1);
903
904 bool wait = false;
905
906 // refer to the JVM book page 47 for description of steps
907 // Step 1
908 {
909 Handle h_init_lock(THREAD, init_lock());
910 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
911
912 Thread *self = THREAD; // it's passed the current thread
913
914 // Step 2
915 // If we were to use wait() instead of waitInterruptibly() then
916 // we might end up throwing IE from link/symbol resolution sites
917 // that aren't expected to throw. This would wreak havoc. See 6320309.
918 while(is_being_initialized() && !is_reentrant_initialization(self)) {
919 wait = true;
920 ol.waitUninterruptibly(CHECK);
921 }
922
923 // Step 3
924 if (is_being_initialized() && is_reentrant_initialization(self)) {
925 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
926 return;
927 }
928
929 // Step 4
930 if (is_initialized()) {
931 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
932 return;
933 }
934
935 // Step 5
936 if (is_in_error_state()) {
937 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
938 ResourceMark rm(THREAD);
939 const char* desc = "Could not initialize class ";
940 const char* className = external_name();
941 size_t msglen = strlen(desc) + strlen(className) + 1;
942 char* message = NEW_RESOURCE_ARRAY(char, msglen);
943 if (NULL == message) {
944 // Out of memory: can't create detailed error message
945 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
946 } else {
947 jio_snprintf(message, msglen, "%s%s", desc, className);
948 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
949 }
950 }
951
952 // Step 6
953 set_init_state(being_initialized);
954 set_init_thread(self);
955 }
956
957 // Step 7
958 // Next, if C is a class rather than an interface, initialize it's super class and super
959 // interfaces.
960 if (!is_interface()) {
961 Klass* super_klass = super();
962 if (super_klass != NULL && super_klass->should_be_initialized()) {
963 super_klass->initialize(THREAD);
964 }
965 // If C implements any interface that declares a non-static, concrete method,
966 // the initialization of C triggers initialization of its super interfaces.
967 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
968 // having a superinterface that declares, non-static, concrete methods
969 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
970 initialize_super_interfaces(THREAD);
971 }
972
973 // If any exceptions, complete abruptly, throwing the same exception as above.
974 if (HAS_PENDING_EXCEPTION) {
975 Handle e(THREAD, PENDING_EXCEPTION);
976 CLEAR_PENDING_EXCEPTION;
977 {
978 EXCEPTION_MARK;
979 // Locks object, set state, and notify all waiting threads
980 set_initialization_state_and_notify(initialization_error, THREAD);
981 CLEAR_PENDING_EXCEPTION;
982 }
983 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
984 THROW_OOP(e());
985 }
986 }
987
988
989 // Look for aot compiled methods for this klass, including class initializer.
990 AOTLoader::load_for_klass(this, THREAD);
991
992 // Step 8
993 {
994 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
995 JavaThread* jt = (JavaThread*)THREAD;
996 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
997 // Timer includes any side effects of class initialization (resolution,
998 // etc), but not recursive entry into call_class_initializer().
999 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1000 ClassLoader::perf_class_init_selftime(),
1001 ClassLoader::perf_classes_inited(),
1002 jt->get_thread_stat()->perf_recursion_counts_addr(),
1003 jt->get_thread_stat()->perf_timers_addr(),
1004 PerfClassTraceTime::CLASS_CLINIT);
1005 call_class_initializer(THREAD);
1006 }
1007
1008 // Step 9
1009 if (!HAS_PENDING_EXCEPTION) {
1010 set_initialization_state_and_notify(fully_initialized, CHECK);
1011 {
1012 debug_only(vtable().verify(tty, true);)
1013 }
1014 }
1015 else {
1016 // Step 10 and 11
1017 Handle e(THREAD, PENDING_EXCEPTION);
1018 CLEAR_PENDING_EXCEPTION;
1019 // JVMTI has already reported the pending exception
1020 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1021 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1022 {
1023 EXCEPTION_MARK;
1024 set_initialization_state_and_notify(initialization_error, THREAD);
1025 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1026 // JVMTI has already reported the pending exception
1027 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1028 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1029 }
1030 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1031 if (e->is_a(SystemDictionary::Error_klass())) {
1032 THROW_OOP(e());
1033 } else {
1034 JavaCallArguments args(e);
1035 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1036 vmSymbols::throwable_void_signature(),
1037 &args);
1038 }
1039 }
1040 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1041 }
1042
1043
1044 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1045 Handle h_init_lock(THREAD, init_lock());
1046 if (h_init_lock() != NULL) {
1047 ObjectLocker ol(h_init_lock, THREAD);
1048 set_init_state(state);
1049 fence_and_clear_init_lock();
1050 ol.notify_all(CHECK);
1051 } else {
1052 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1053 set_init_state(state);
1054 }
1055 }
1056
1057 Klass* InstanceKlass::implementor() const {
1058 Klass* volatile* k = adr_implementor();
1059 if (k == NULL) {
1060 return NULL;
1061 } else {
1062 // This load races with inserts, and therefore needs acquire.
1063 Klass* kls = OrderAccess::load_acquire(k);
1064 if (kls != NULL && !kls->is_loader_alive()) {
1065 return NULL; // don't return unloaded class
1066 } else {
1067 return kls;
1068 }
1069 }
1070 }
1071
1072
1073 void InstanceKlass::set_implementor(Klass* k) {
1074 assert_lock_strong(Compile_lock);
1075 assert(is_interface(), "not interface");
1076 Klass* volatile* addr = adr_implementor();
1077 assert(addr != NULL, "null addr");
1078 if (addr != NULL) {
1079 OrderAccess::release_store(addr, k);
1080 }
1081 }
1082
1083 int InstanceKlass::nof_implementors() const {
1084 assert_lock_strong(Compile_lock);
1085 Klass* k = implementor();
1086 if (k == NULL) {
1087 return 0;
1088 } else if (k != this) {
1089 return 1;
1090 } else {
1091 return 2;
1092 }
1093 }
1094
1095 // The embedded _implementor field can only record one implementor.
1096 // When there are more than one implementors, the _implementor field
1097 // is set to the interface Klass* itself. Following are the possible
1098 // values for the _implementor field:
1099 // NULL - no implementor
1100 // implementor Klass* - one implementor
1101 // self - more than one implementor
1102 //
1103 // The _implementor field only exists for interfaces.
1104 void InstanceKlass::add_implementor(Klass* k) {
1105 assert_lock_strong(Compile_lock);
1106 assert(is_interface(), "not interface");
1107 // Filter out my subinterfaces.
1108 // (Note: Interfaces are never on the subklass list.)
1109 if (InstanceKlass::cast(k)->is_interface()) return;
1110
1111 // Filter out subclasses whose supers already implement me.
1112 // (Note: CHA must walk subclasses of direct implementors
1113 // in order to locate indirect implementors.)
1114 Klass* sk = k->super();
1115 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1116 // We only need to check one immediate superclass, since the
1117 // implements_interface query looks at transitive_interfaces.
1118 // Any supers of the super have the same (or fewer) transitive_interfaces.
1119 return;
1120
1121 Klass* ik = implementor();
1122 if (ik == NULL) {
1123 set_implementor(k);
1124 } else if (ik != this) {
1125 // There is already an implementor. Use itself as an indicator of
1126 // more than one implementors.
1127 set_implementor(this);
1128 }
1129
1130 // The implementor also implements the transitive_interfaces
1131 for (int index = 0; index < local_interfaces()->length(); index++) {
1132 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1133 }
1134 }
1135
1136 void InstanceKlass::init_implementor() {
1137 if (is_interface()) {
1138 set_implementor(NULL);
1139 }
1140 }
1141
1142
1143 void InstanceKlass::process_interfaces(Thread *thread) {
1144 // link this class into the implementors list of every interface it implements
1145 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1146 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1147 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1148 assert(interf->is_interface(), "expected interface");
1149 interf->add_implementor(this);
1150 }
1151 }
1152
1153 bool InstanceKlass::can_be_primary_super_slow() const {
1154 if (is_interface())
1155 return false;
1156 else
1157 return Klass::can_be_primary_super_slow();
1158 }
1159
1160 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1161 Array<InstanceKlass*>* transitive_interfaces) {
1162 // The secondaries are the implemented interfaces.
1163 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1164 int num_secondaries = num_extra_slots + interfaces->length();
1165 if (num_secondaries == 0) {
1166 // Must share this for correct bootstrapping!
1167 set_secondary_supers(Universe::the_empty_klass_array());
1168 return NULL;
1169 } else if (num_extra_slots == 0) {
1170 // The secondary super list is exactly the same as the transitive interfaces, so
1171 // let's use it instead of making a copy.
1172 // Redefine classes has to be careful not to delete this!
1173 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1174 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1175 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1176 return NULL;
1177 } else {
1178 // Copy transitive interfaces to a temporary growable array to be constructed
1179 // into the secondary super list with extra slots.
1180 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1181 for (int i = 0; i < interfaces->length(); i++) {
1182 secondaries->push(interfaces->at(i));
1183 }
1184 return secondaries;
1185 }
1186 }
1187
1188 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1189 if (k->is_interface()) {
1190 return implements_interface(k);
1191 } else {
1192 return Klass::compute_is_subtype_of(k);
1193 }
1194 }
1195
1196 bool InstanceKlass::implements_interface(Klass* k) const {
1197 if (this == k) return true;
1198 assert(k->is_interface(), "should be an interface class");
1199 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1200 if (transitive_interfaces()->at(i) == k) {
1201 return true;
1202 }
1203 }
1204 return false;
1205 }
1206
1207 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1208 // Verify direct super interface
1209 if (this == k) return true;
1210 assert(k->is_interface(), "should be an interface class");
1211 for (int i = 0; i < local_interfaces()->length(); i++) {
1212 if (local_interfaces()->at(i) == k) {
1213 return true;
1214 }
1215 }
1216 return false;
1217 }
1218
1219 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1220 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1221 int size = objArrayOopDesc::object_size(length);
1222 Klass* ak = array_klass(n, CHECK_NULL);
1223 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1224 /* do_zero */ true, CHECK_NULL);
1225 return o;
1226 }
1227
1228 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1229 if (TraceFinalizerRegistration) {
1230 tty->print("Registered ");
1231 i->print_value_on(tty);
1232 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1233 }
1234 instanceHandle h_i(THREAD, i);
1235 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1236 JavaValue result(T_VOID);
1237 JavaCallArguments args(h_i);
1238 methodHandle mh (THREAD, Universe::finalizer_register_method());
1239 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1240 return h_i();
1241 }
1242
1243 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1244 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1245 int size = size_helper(); // Query before forming handle.
1246
1247 instanceOop i;
1248
1249 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1250 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1251 i = register_finalizer(i, CHECK_NULL);
1252 }
1253 return i;
1254 }
1255
1256 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1257 return instanceHandle(THREAD, allocate_instance(THREAD));
1258 }
1259
1260 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1261 if (is_interface() || is_abstract()) {
1262 ResourceMark rm(THREAD);
1263 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1264 : vmSymbols::java_lang_InstantiationException(), external_name());
1265 }
1266 if (this == SystemDictionary::Class_klass()) {
1267 ResourceMark rm(THREAD);
1268 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1269 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1270 }
1271 }
1272
1273 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1274 // Need load-acquire for lock-free read
1275 if (array_klasses_acquire() == NULL) {
1276 if (or_null) return NULL;
1277
1278 ResourceMark rm;
1279 JavaThread *jt = (JavaThread *)THREAD;
1280 {
1281 // Atomic creation of array_klasses
1282 MutexLocker mc(Compile_lock, THREAD); // for vtables
1283 MutexLocker ma(MultiArray_lock, THREAD);
1284
1285 // Check if update has already taken place
1286 if (array_klasses() == NULL) {
1287 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1288 // use 'release' to pair with lock-free load
1289 release_set_array_klasses(k);
1290 }
1291 }
1292 }
1293 // _this will always be set at this point
1294 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1295 if (or_null) {
1296 return oak->array_klass_or_null(n);
1297 }
1298 return oak->array_klass(n, THREAD);
1299 }
1300
1301 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1302 return array_klass_impl(or_null, 1, THREAD);
1303 }
1304
1305 static int call_class_initializer_counter = 0; // for debugging
1306
1307 Method* InstanceKlass::class_initializer() const {
1308 Method* clinit = find_method(
1309 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1310 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1311 return clinit;
1312 }
1313 return NULL;
1314 }
1315
1316 void InstanceKlass::call_class_initializer(TRAPS) {
1317 if (ReplayCompiles &&
1318 (ReplaySuppressInitializers == 1 ||
1319 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1320 // Hide the existence of the initializer for the purpose of replaying the compile
1321 return;
1322 }
1323
1324 methodHandle h_method(THREAD, class_initializer());
1325 assert(!is_initialized(), "we cannot initialize twice");
1326 LogTarget(Info, class, init) lt;
1327 if (lt.is_enabled()) {
1328 ResourceMark rm;
1329 LogStream ls(lt);
1330 ls.print("%d Initializing ", call_class_initializer_counter++);
1331 name()->print_value_on(&ls);
1332 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1333 }
1334 if (h_method() != NULL) {
1335 JavaCallArguments args; // No arguments
1336 JavaValue result(T_VOID);
1337 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1338 }
1339 }
1340
1341
1342 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1343 InterpreterOopMap* entry_for) {
1344 // Lazily create the _oop_map_cache at first request
1345 // Lock-free access requires load_acquire.
1346 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1347 if (oop_map_cache == NULL) {
1348 MutexLocker x(OopMapCacheAlloc_lock);
1349 // Check if _oop_map_cache was allocated while we were waiting for this lock
1350 if ((oop_map_cache = _oop_map_cache) == NULL) {
1351 oop_map_cache = new OopMapCache();
1352 // Ensure _oop_map_cache is stable, since it is examined without a lock
1353 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1354 }
1355 }
1356 // _oop_map_cache is constant after init; lookup below does its own locking.
1357 oop_map_cache->lookup(method, bci, entry_for);
1358 }
1359
1360
1361 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1362 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1363 Symbol* f_name = fs.name();
1364 Symbol* f_sig = fs.signature();
1365 if (f_name == name && f_sig == sig) {
1366 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1367 return true;
1368 }
1369 }
1370 return false;
1371 }
1372
1373
1374 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1375 const int n = local_interfaces()->length();
1376 for (int i = 0; i < n; i++) {
1377 Klass* intf1 = local_interfaces()->at(i);
1378 assert(intf1->is_interface(), "just checking type");
1379 // search for field in current interface
1380 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1381 assert(fd->is_static(), "interface field must be static");
1382 return intf1;
1383 }
1384 // search for field in direct superinterfaces
1385 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1386 if (intf2 != NULL) return intf2;
1387 }
1388 // otherwise field lookup fails
1389 return NULL;
1390 }
1391
1392
1393 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1394 // search order according to newest JVM spec (5.4.3.2, p.167).
1395 // 1) search for field in current klass
1396 if (find_local_field(name, sig, fd)) {
1397 return const_cast<InstanceKlass*>(this);
1398 }
1399 // 2) search for field recursively in direct superinterfaces
1400 { Klass* intf = find_interface_field(name, sig, fd);
1401 if (intf != NULL) return intf;
1402 }
1403 // 3) apply field lookup recursively if superclass exists
1404 { Klass* supr = super();
1405 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1406 }
1407 // 4) otherwise field lookup fails
1408 return NULL;
1409 }
1410
1411
1412 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1413 // search order according to newest JVM spec (5.4.3.2, p.167).
1414 // 1) search for field in current klass
1415 if (find_local_field(name, sig, fd)) {
1416 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1417 }
1418 // 2) search for field recursively in direct superinterfaces
1419 if (is_static) {
1420 Klass* intf = find_interface_field(name, sig, fd);
1421 if (intf != NULL) return intf;
1422 }
1423 // 3) apply field lookup recursively if superclass exists
1424 { Klass* supr = super();
1425 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1426 }
1427 // 4) otherwise field lookup fails
1428 return NULL;
1429 }
1430
1431
1432 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1433 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1434 if (fs.offset() == offset) {
1435 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1436 if (fd->is_static() == is_static) return true;
1437 }
1438 }
1439 return false;
1440 }
1441
1442
1443 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1444 Klass* klass = const_cast<InstanceKlass*>(this);
1445 while (klass != NULL) {
1446 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1447 return true;
1448 }
1449 klass = klass->super();
1450 }
1451 return false;
1452 }
1453
1454
1455 void InstanceKlass::methods_do(void f(Method* method)) {
1456 // Methods aren't stable until they are loaded. This can be read outside
1457 // a lock through the ClassLoaderData for profiling
1458 if (!is_loaded()) {
1459 return;
1460 }
1461
1462 int len = methods()->length();
1463 for (int index = 0; index < len; index++) {
1464 Method* m = methods()->at(index);
1465 assert(m->is_method(), "must be method");
1466 f(m);
1467 }
1468 }
1469
1470
1471 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1472 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1473 if (fs.access_flags().is_static()) {
1474 fieldDescriptor& fd = fs.field_descriptor();
1475 cl->do_field(&fd);
1476 }
1477 }
1478 }
1479
1480
1481 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1482 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1483 if (fs.access_flags().is_static()) {
1484 fieldDescriptor& fd = fs.field_descriptor();
1485 f(&fd, mirror, CHECK);
1486 }
1487 }
1488 }
1489
1490
1491 static int compare_fields_by_offset(int* a, int* b) {
1492 return a[0] - b[0];
1493 }
1494
1495 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1496 InstanceKlass* super = superklass();
1497 if (super != NULL) {
1498 super->do_nonstatic_fields(cl);
1499 }
1500 fieldDescriptor fd;
1501 int length = java_fields_count();
1502 // In DebugInfo nonstatic fields are sorted by offset.
1503 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1504 int j = 0;
1505 for (int i = 0; i < length; i += 1) {
1506 fd.reinitialize(this, i);
1507 if (!fd.is_static()) {
1508 fields_sorted[j + 0] = fd.offset();
1509 fields_sorted[j + 1] = i;
1510 j += 2;
1511 }
1512 }
1513 if (j > 0) {
1514 length = j;
1515 // _sort_Fn is defined in growableArray.hpp.
1516 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1517 for (int i = 0; i < length; i += 2) {
1518 fd.reinitialize(this, fields_sorted[i + 1]);
1519 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1520 cl->do_field(&fd);
1521 }
1522 }
1523 FREE_C_HEAP_ARRAY(int, fields_sorted);
1524 }
1525
1526
1527 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1528 if (array_klasses() != NULL)
1529 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1530 }
1531
1532 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1533 if (array_klasses() != NULL)
1534 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1535 }
1536
1537 #ifdef ASSERT
1538 static int linear_search(const Array<Method*>* methods,
1539 const Symbol* name,
1540 const Symbol* signature) {
1541 const int len = methods->length();
1542 for (int index = 0; index < len; index++) {
1543 const Method* const m = methods->at(index);
1544 assert(m->is_method(), "must be method");
1545 if (m->signature() == signature && m->name() == name) {
1546 return index;
1547 }
1548 }
1549 return -1;
1550 }
1551 #endif
1552
1553 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1554 int len = methods->length();
1555 // methods are sorted, so do binary search
1556 int l = 0;
1557 int h = len - 1;
1558 while (l <= h) {
1559 int mid = (l + h) >> 1;
1560 Method* m = methods->at(mid);
1561 assert(m->is_method(), "must be method");
1562 int res = m->name()->fast_compare(name);
1563 if (res == 0) {
1564 return mid;
1565 } else if (res < 0) {
1566 l = mid + 1;
1567 } else {
1568 h = mid - 1;
1569 }
1570 }
1571 return -1;
1572 }
1573
1574 // find_method looks up the name/signature in the local methods array
1575 Method* InstanceKlass::find_method(const Symbol* name,
1576 const Symbol* signature) const {
1577 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1578 }
1579
1580 Method* InstanceKlass::find_method_impl(const Symbol* name,
1581 const Symbol* signature,
1582 OverpassLookupMode overpass_mode,
1583 StaticLookupMode static_mode,
1584 PrivateLookupMode private_mode) const {
1585 return InstanceKlass::find_method_impl(methods(),
1586 name,
1587 signature,
1588 overpass_mode,
1589 static_mode,
1590 private_mode);
1591 }
1592
1593 // find_instance_method looks up the name/signature in the local methods array
1594 // and skips over static methods
1595 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1596 const Symbol* name,
1597 const Symbol* signature,
1598 PrivateLookupMode private_mode) {
1599 Method* const meth = InstanceKlass::find_method_impl(methods,
1600 name,
1601 signature,
1602 find_overpass,
1603 skip_static,
1604 private_mode);
1605 assert(((meth == NULL) || !meth->is_static()),
1606 "find_instance_method should have skipped statics");
1607 return meth;
1608 }
1609
1610 // find_instance_method looks up the name/signature in the local methods array
1611 // and skips over static methods
1612 Method* InstanceKlass::find_instance_method(const Symbol* name,
1613 const Symbol* signature,
1614 PrivateLookupMode private_mode) const {
1615 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1616 }
1617
1618 // Find looks up the name/signature in the local methods array
1619 // and filters on the overpass, static and private flags
1620 // This returns the first one found
1621 // note that the local methods array can have up to one overpass, one static
1622 // and one instance (private or not) with the same name/signature
1623 Method* InstanceKlass::find_local_method(const Symbol* name,
1624 const Symbol* signature,
1625 OverpassLookupMode overpass_mode,
1626 StaticLookupMode static_mode,
1627 PrivateLookupMode private_mode) const {
1628 return InstanceKlass::find_method_impl(methods(),
1629 name,
1630 signature,
1631 overpass_mode,
1632 static_mode,
1633 private_mode);
1634 }
1635
1636 // Find looks up the name/signature in the local methods array
1637 // and filters on the overpass, static and private flags
1638 // This returns the first one found
1639 // note that the local methods array can have up to one overpass, one static
1640 // and one instance (private or not) with the same name/signature
1641 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1642 const Symbol* name,
1643 const Symbol* signature,
1644 OverpassLookupMode overpass_mode,
1645 StaticLookupMode static_mode,
1646 PrivateLookupMode private_mode) {
1647 return InstanceKlass::find_method_impl(methods,
1648 name,
1649 signature,
1650 overpass_mode,
1651 static_mode,
1652 private_mode);
1653 }
1654
1655 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1656 const Symbol* name,
1657 const Symbol* signature) {
1658 return InstanceKlass::find_method_impl(methods,
1659 name,
1660 signature,
1661 find_overpass,
1662 find_static,
1663 find_private);
1664 }
1665
1666 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1667 const Symbol* name,
1668 const Symbol* signature,
1669 OverpassLookupMode overpass_mode,
1670 StaticLookupMode static_mode,
1671 PrivateLookupMode private_mode) {
1672 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1673 return hit >= 0 ? methods->at(hit): NULL;
1674 }
1675
1676 // true if method matches signature and conforms to skipping_X conditions.
1677 static bool method_matches(const Method* m,
1678 const Symbol* signature,
1679 bool skipping_overpass,
1680 bool skipping_static,
1681 bool skipping_private) {
1682 return ((m->signature() == signature) &&
1683 (!skipping_overpass || !m->is_overpass()) &&
1684 (!skipping_static || !m->is_static()) &&
1685 (!skipping_private || !m->is_private()));
1686 }
1687
1688 // Used directly for default_methods to find the index into the
1689 // default_vtable_indices, and indirectly by find_method
1690 // find_method_index looks in the local methods array to return the index
1691 // of the matching name/signature. If, overpass methods are being ignored,
1692 // the search continues to find a potential non-overpass match. This capability
1693 // is important during method resolution to prefer a static method, for example,
1694 // over an overpass method.
1695 // There is the possibility in any _method's array to have the same name/signature
1696 // for a static method, an overpass method and a local instance method
1697 // To correctly catch a given method, the search criteria may need
1698 // to explicitly skip the other two. For local instance methods, it
1699 // is often necessary to skip private methods
1700 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1701 const Symbol* name,
1702 const Symbol* signature,
1703 OverpassLookupMode overpass_mode,
1704 StaticLookupMode static_mode,
1705 PrivateLookupMode private_mode) {
1706 const bool skipping_overpass = (overpass_mode == skip_overpass);
1707 const bool skipping_static = (static_mode == skip_static);
1708 const bool skipping_private = (private_mode == skip_private);
1709 const int hit = binary_search(methods, name);
1710 if (hit != -1) {
1711 const Method* const m = methods->at(hit);
1712
1713 // Do linear search to find matching signature. First, quick check
1714 // for common case, ignoring overpasses if requested.
1715 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1716 return hit;
1717 }
1718
1719 // search downwards through overloaded methods
1720 int i;
1721 for (i = hit - 1; i >= 0; --i) {
1722 const Method* const m = methods->at(i);
1723 assert(m->is_method(), "must be method");
1724 if (m->name() != name) {
1725 break;
1726 }
1727 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1728 return i;
1729 }
1730 }
1731 // search upwards
1732 for (i = hit + 1; i < methods->length(); ++i) {
1733 const Method* const m = methods->at(i);
1734 assert(m->is_method(), "must be method");
1735 if (m->name() != name) {
1736 break;
1737 }
1738 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1739 return i;
1740 }
1741 }
1742 // not found
1743 #ifdef ASSERT
1744 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1745 linear_search(methods, name, signature);
1746 assert(-1 == index, "binary search should have found entry %d", index);
1747 #endif
1748 }
1749 return -1;
1750 }
1751
1752 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1753 return find_method_by_name(methods(), name, end);
1754 }
1755
1756 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1757 const Symbol* name,
1758 int* end_ptr) {
1759 assert(end_ptr != NULL, "just checking");
1760 int start = binary_search(methods, name);
1761 int end = start + 1;
1762 if (start != -1) {
1763 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1764 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1765 *end_ptr = end;
1766 return start;
1767 }
1768 return -1;
1769 }
1770
1771 // uncached_lookup_method searches both the local class methods array and all
1772 // superclasses methods arrays, skipping any overpass methods in superclasses,
1773 // and possibly skipping private methods.
1774 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1775 const Symbol* signature,
1776 OverpassLookupMode overpass_mode,
1777 PrivateLookupMode private_mode) const {
1778 OverpassLookupMode overpass_local_mode = overpass_mode;
1779 const Klass* klass = this;
1780 while (klass != NULL) {
1781 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1782 signature,
1783 overpass_local_mode,
1784 find_static,
1785 private_mode);
1786 if (method != NULL) {
1787 return method;
1788 }
1789 klass = klass->super();
1790 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1791 }
1792 return NULL;
1793 }
1794
1795 #ifdef ASSERT
1796 // search through class hierarchy and return true if this class or
1797 // one of the superclasses was redefined
1798 bool InstanceKlass::has_redefined_this_or_super() const {
1799 const Klass* klass = this;
1800 while (klass != NULL) {
1801 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1802 return true;
1803 }
1804 klass = klass->super();
1805 }
1806 return false;
1807 }
1808 #endif
1809
1810 // lookup a method in the default methods list then in all transitive interfaces
1811 // Do NOT return private or static methods
1812 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1813 Symbol* signature) const {
1814 Method* m = NULL;
1815 if (default_methods() != NULL) {
1816 m = find_method(default_methods(), name, signature);
1817 }
1818 // Look up interfaces
1819 if (m == NULL) {
1820 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1821 }
1822 return m;
1823 }
1824
1825 // lookup a method in all the interfaces that this class implements
1826 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1827 // They should only be found in the initial InterfaceMethodRef
1828 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1829 Symbol* signature,
1830 DefaultsLookupMode defaults_mode) const {
1831 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1832 int num_ifs = all_ifs->length();
1833 InstanceKlass *ik = NULL;
1834 for (int i = 0; i < num_ifs; i++) {
1835 ik = all_ifs->at(i);
1836 Method* m = ik->lookup_method(name, signature);
1837 if (m != NULL && m->is_public() && !m->is_static() &&
1838 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1839 return m;
1840 }
1841 }
1842 return NULL;
1843 }
1844
1845 /* jni_id_for_impl for jfieldIds only */
1846 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1847 MutexLocker ml(JfieldIdCreation_lock);
1848 // Retry lookup after we got the lock
1849 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1850 if (probe == NULL) {
1851 // Slow case, allocate new static field identifier
1852 probe = new JNIid(this, offset, jni_ids());
1853 set_jni_ids(probe);
1854 }
1855 return probe;
1856 }
1857
1858
1859 /* jni_id_for for jfieldIds only */
1860 JNIid* InstanceKlass::jni_id_for(int offset) {
1861 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1862 if (probe == NULL) {
1863 probe = jni_id_for_impl(offset);
1864 }
1865 return probe;
1866 }
1867
1868 u2 InstanceKlass::enclosing_method_data(int offset) const {
1869 const Array<jushort>* const inner_class_list = inner_classes();
1870 if (inner_class_list == NULL) {
1871 return 0;
1872 }
1873 const int length = inner_class_list->length();
1874 if (length % inner_class_next_offset == 0) {
1875 return 0;
1876 }
1877 const int index = length - enclosing_method_attribute_size;
1878 assert(offset < enclosing_method_attribute_size, "invalid offset");
1879 return inner_class_list->at(index + offset);
1880 }
1881
1882 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1883 u2 method_index) {
1884 Array<jushort>* inner_class_list = inner_classes();
1885 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1886 int length = inner_class_list->length();
1887 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1888 int index = length - enclosing_method_attribute_size;
1889 inner_class_list->at_put(
1890 index + enclosing_method_class_index_offset, class_index);
1891 inner_class_list->at_put(
1892 index + enclosing_method_method_index_offset, method_index);
1893 }
1894 }
1895
1896 // Lookup or create a jmethodID.
1897 // This code is called by the VMThread and JavaThreads so the
1898 // locking has to be done very carefully to avoid deadlocks
1899 // and/or other cache consistency problems.
1900 //
1901 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1902 size_t idnum = (size_t)method_h->method_idnum();
1903 jmethodID* jmeths = methods_jmethod_ids_acquire();
1904 size_t length = 0;
1905 jmethodID id = NULL;
1906
1907 // We use a double-check locking idiom here because this cache is
1908 // performance sensitive. In the normal system, this cache only
1909 // transitions from NULL to non-NULL which is safe because we use
1910 // release_set_methods_jmethod_ids() to advertise the new cache.
1911 // A partially constructed cache should never be seen by a racing
1912 // thread. We also use release_store() to save a new jmethodID
1913 // in the cache so a partially constructed jmethodID should never be
1914 // seen either. Cache reads of existing jmethodIDs proceed without a
1915 // lock, but cache writes of a new jmethodID requires uniqueness and
1916 // creation of the cache itself requires no leaks so a lock is
1917 // generally acquired in those two cases.
1918 //
1919 // If the RedefineClasses() API has been used, then this cache can
1920 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1921 // Cache creation requires no leaks and we require safety between all
1922 // cache accesses and freeing of the old cache so a lock is generally
1923 // acquired when the RedefineClasses() API has been used.
1924
1925 if (jmeths != NULL) {
1926 // the cache already exists
1927 if (!idnum_can_increment()) {
1928 // the cache can't grow so we can just get the current values
1929 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1930 } else {
1931 // cache can grow so we have to be more careful
1932 if (Threads::number_of_threads() == 0 ||
1933 SafepointSynchronize::is_at_safepoint()) {
1934 // we're single threaded or at a safepoint - no locking needed
1935 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1936 } else {
1937 MutexLocker ml(JmethodIdCreation_lock);
1938 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1939 }
1940 }
1941 }
1942 // implied else:
1943 // we need to allocate a cache so default length and id values are good
1944
1945 if (jmeths == NULL || // no cache yet
1946 length <= idnum || // cache is too short
1947 id == NULL) { // cache doesn't contain entry
1948
1949 // This function can be called by the VMThread so we have to do all
1950 // things that might block on a safepoint before grabbing the lock.
1951 // Otherwise, we can deadlock with the VMThread or have a cache
1952 // consistency issue. These vars keep track of what we might have
1953 // to free after the lock is dropped.
1954 jmethodID to_dealloc_id = NULL;
1955 jmethodID* to_dealloc_jmeths = NULL;
1956
1957 // may not allocate new_jmeths or use it if we allocate it
1958 jmethodID* new_jmeths = NULL;
1959 if (length <= idnum) {
1960 // allocate a new cache that might be used
1961 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1962 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1963 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1964 // cache size is stored in element[0], other elements offset by one
1965 new_jmeths[0] = (jmethodID)size;
1966 }
1967
1968 // allocate a new jmethodID that might be used
1969 jmethodID new_id = NULL;
1970 if (method_h->is_old() && !method_h->is_obsolete()) {
1971 // The method passed in is old (but not obsolete), we need to use the current version
1972 Method* current_method = method_with_idnum((int)idnum);
1973 assert(current_method != NULL, "old and but not obsolete, so should exist");
1974 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1975 } else {
1976 // It is the current version of the method or an obsolete method,
1977 // use the version passed in
1978 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1979 }
1980
1981 if (Threads::number_of_threads() == 0 ||
1982 SafepointSynchronize::is_at_safepoint()) {
1983 // we're single threaded or at a safepoint - no locking needed
1984 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1985 &to_dealloc_id, &to_dealloc_jmeths);
1986 } else {
1987 MutexLocker ml(JmethodIdCreation_lock);
1988 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1989 &to_dealloc_id, &to_dealloc_jmeths);
1990 }
1991
1992 // The lock has been dropped so we can free resources.
1993 // Free up either the old cache or the new cache if we allocated one.
1994 if (to_dealloc_jmeths != NULL) {
1995 FreeHeap(to_dealloc_jmeths);
1996 }
1997 // free up the new ID since it wasn't needed
1998 if (to_dealloc_id != NULL) {
1999 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2000 }
2001 }
2002 return id;
2003 }
2004
2005 // Figure out how many jmethodIDs haven't been allocated, and make
2006 // sure space for them is pre-allocated. This makes getting all
2007 // method ids much, much faster with classes with more than 8
2008 // methods, and has a *substantial* effect on performance with jvmti
2009 // code that loads all jmethodIDs for all classes.
2010 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2011 int new_jmeths = 0;
2012 int length = methods()->length();
2013 for (int index = start_offset; index < length; index++) {
2014 Method* m = methods()->at(index);
2015 jmethodID id = m->find_jmethod_id_or_null();
2016 if (id == NULL) {
2017 new_jmeths++;
2018 }
2019 }
2020 if (new_jmeths != 0) {
2021 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2022 }
2023 }
2024
2025 // Common code to fetch the jmethodID from the cache or update the
2026 // cache with the new jmethodID. This function should never do anything
2027 // that causes the caller to go to a safepoint or we can deadlock with
2028 // the VMThread or have cache consistency issues.
2029 //
2030 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2031 size_t idnum, jmethodID new_id,
2032 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2033 jmethodID** to_dealloc_jmeths_p) {
2034 assert(new_id != NULL, "sanity check");
2035 assert(to_dealloc_id_p != NULL, "sanity check");
2036 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2037 assert(Threads::number_of_threads() == 0 ||
2038 SafepointSynchronize::is_at_safepoint() ||
2039 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2040
2041 // reacquire the cache - we are locked, single threaded or at a safepoint
2042 jmethodID* jmeths = methods_jmethod_ids_acquire();
2043 jmethodID id = NULL;
2044 size_t length = 0;
2045
2046 if (jmeths == NULL || // no cache yet
2047 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2048 if (jmeths != NULL) {
2049 // copy any existing entries from the old cache
2050 for (size_t index = 0; index < length; index++) {
2051 new_jmeths[index+1] = jmeths[index+1];
2052 }
2053 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2054 }
2055 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2056 } else {
2057 // fetch jmethodID (if any) from the existing cache
2058 id = jmeths[idnum+1];
2059 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2060 }
2061 if (id == NULL) {
2062 // No matching jmethodID in the existing cache or we have a new
2063 // cache or we just grew the cache. This cache write is done here
2064 // by the first thread to win the foot race because a jmethodID
2065 // needs to be unique once it is generally available.
2066 id = new_id;
2067
2068 // The jmethodID cache can be read while unlocked so we have to
2069 // make sure the new jmethodID is complete before installing it
2070 // in the cache.
2071 OrderAccess::release_store(&jmeths[idnum+1], id);
2072 } else {
2073 *to_dealloc_id_p = new_id; // save new id for later delete
2074 }
2075 return id;
2076 }
2077
2078
2079 // Common code to get the jmethodID cache length and the jmethodID
2080 // value at index idnum if there is one.
2081 //
2082 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2083 size_t idnum, size_t *length_p, jmethodID* id_p) {
2084 assert(cache != NULL, "sanity check");
2085 assert(length_p != NULL, "sanity check");
2086 assert(id_p != NULL, "sanity check");
2087
2088 // cache size is stored in element[0], other elements offset by one
2089 *length_p = (size_t)cache[0];
2090 if (*length_p <= idnum) { // cache is too short
2091 *id_p = NULL;
2092 } else {
2093 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2094 }
2095 }
2096
2097
2098 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2099 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2100 size_t idnum = (size_t)method->method_idnum();
2101 jmethodID* jmeths = methods_jmethod_ids_acquire();
2102 size_t length; // length assigned as debugging crumb
2103 jmethodID id = NULL;
2104 if (jmeths != NULL && // If there is a cache
2105 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2106 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2107 }
2108 return id;
2109 }
2110
2111 inline DependencyContext InstanceKlass::dependencies() {
2112 DependencyContext dep_context(&_dep_context);
2113 return dep_context;
2114 }
2115
2116 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2117 return dependencies().mark_dependent_nmethods(changes);
2118 }
2119
2120 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2121 dependencies().add_dependent_nmethod(nm);
2122 }
2123
2124 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2125 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2126 }
2127
2128 #ifndef PRODUCT
2129 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2130 dependencies().print_dependent_nmethods(verbose);
2131 }
2132
2133 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2134 return dependencies().is_dependent_nmethod(nm);
2135 }
2136 #endif //PRODUCT
2137
2138 void InstanceKlass::clean_weak_instanceklass_links() {
2139 clean_implementors_list();
2140 clean_method_data();
2141
2142 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2143 DependencyContext dep_context(&_dep_context);
2144 dep_context.expunge_stale_entries();
2145 }
2146
2147 void InstanceKlass::clean_implementors_list() {
2148 assert(is_loader_alive(), "this klass should be live");
2149 if (is_interface()) {
2150 assert (ClassUnloading, "only called for ClassUnloading");
2151 for (;;) {
2152 // Use load_acquire due to competing with inserts
2153 Klass* impl = OrderAccess::load_acquire(adr_implementor());
2154 if (impl != NULL && !impl->is_loader_alive()) {
2155 // NULL this field, might be an unloaded klass or NULL
2156 Klass* volatile* klass = adr_implementor();
2157 if (Atomic::cmpxchg((Klass*)NULL, klass, impl) == impl) {
2158 // Successfully unlinking implementor.
2159 if (log_is_enabled(Trace, class, unload)) {
2160 ResourceMark rm;
2161 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2162 }
2163 return;
2164 }
2165 } else {
2166 return;
2167 }
2168 }
2169 }
2170 }
2171
2172 void InstanceKlass::clean_method_data() {
2173 for (int m = 0; m < methods()->length(); m++) {
2174 MethodData* mdo = methods()->at(m)->method_data();
2175 if (mdo != NULL) {
2176 mdo->clean_method_data(/*always_clean*/false);
2177 }
2178 }
2179 }
2180
2181 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2182 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2183 ResourceMark rm;
2184 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2185 return false;
2186 }
2187
2188 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2189 if (local_interfaces != NULL) {
2190 int length = local_interfaces->length();
2191 for (int i = 0; i < length; i++) {
2192 InstanceKlass* intf = local_interfaces->at(i);
2193 if (!intf->has_passed_fingerprint_check()) {
2194 ResourceMark rm;
2195 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2196 return false;
2197 }
2198 }
2199 }
2200
2201 return true;
2202 }
2203
2204 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2205 #if INCLUDE_AOT
2206 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2207 if (CalculateClassFingerprint) {
2208 // (1) We are running AOT to generate a shared library.
2209 return true;
2210 }
2211 if (DumpSharedSpaces) {
2212 // (2) We are running -Xshare:dump to create a shared archive
2213 return true;
2214 }
2215 if (UseAOT && is_unsafe_anonymous) {
2216 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2217 return true;
2218 }
2219 #endif
2220
2221 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2222 // but do not store the 64-bit fingerprint to save space.
2223 return false;
2224 }
2225
2226 bool InstanceKlass::has_stored_fingerprint() const {
2227 #if INCLUDE_AOT
2228 return should_store_fingerprint() || is_shared();
2229 #else
2230 return false;
2231 #endif
2232 }
2233
2234 uint64_t InstanceKlass::get_stored_fingerprint() const {
2235 address adr = adr_fingerprint();
2236 if (adr != NULL) {
2237 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2238 }
2239 return 0;
2240 }
2241
2242 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2243 address adr = adr_fingerprint();
2244 if (adr != NULL) {
2245 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2246
2247 ResourceMark rm;
2248 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2249 }
2250 }
2251
2252 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2253 Klass::metaspace_pointers_do(it);
2254
2255 if (log_is_enabled(Trace, cds)) {
2256 ResourceMark rm;
2257 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2258 }
2259
2260 it->push(&_annotations);
2261 it->push((Klass**)&_array_klasses);
2262 it->push(&_constants);
2263 it->push(&_inner_classes);
2264 it->push(&_array_name);
2265 #if INCLUDE_JVMTI
2266 it->push(&_previous_versions);
2267 #endif
2268 it->push(&_methods);
2269 it->push(&_default_methods);
2270 it->push(&_local_interfaces);
2271 it->push(&_transitive_interfaces);
2272 it->push(&_method_ordering);
2273 it->push(&_default_vtable_indices);
2274 it->push(&_fields);
2275
2276 if (itable_length() > 0) {
2277 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2278 int method_table_offset_in_words = ioe->offset()/wordSize;
2279 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2280 / itableOffsetEntry::size();
2281
2282 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2283 if (ioe->interface_klass() != NULL) {
2284 it->push(ioe->interface_klass_addr());
2285 itableMethodEntry* ime = ioe->first_method_entry(this);
2286 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2287 for (int index = 0; index < n; index ++) {
2288 it->push(ime[index].method_addr());
2289 }
2290 }
2291 }
2292 }
2293
2294 it->push(&_nest_members);
2295 }
2296
2297 void InstanceKlass::remove_unshareable_info() {
2298 Klass::remove_unshareable_info();
2299
2300 if (is_in_error_state()) {
2301 // Classes are attempted to link during dumping and may fail,
2302 // but these classes are still in the dictionary and class list in CLD.
2303 // Check in_error state first because in_error is > linked state, so
2304 // is_linked() is true.
2305 // If there's a linking error, there is nothing else to remove.
2306 return;
2307 }
2308
2309 // Reset to the 'allocated' state to prevent any premature accessing to
2310 // a shared class at runtime while the class is still being loaded and
2311 // restored. A class' init_state is set to 'loaded' at runtime when it's
2312 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2313 _init_state = allocated;
2314
2315 {
2316 MutexLocker ml(Compile_lock);
2317 init_implementor();
2318 }
2319
2320 constants()->remove_unshareable_info();
2321
2322 for (int i = 0; i < methods()->length(); i++) {
2323 Method* m = methods()->at(i);
2324 m->remove_unshareable_info();
2325 }
2326
2327 // do array classes also.
2328 if (array_klasses() != NULL) {
2329 array_klasses()->remove_unshareable_info();
2330 }
2331
2332 // These are not allocated from metaspace, but they should should all be empty
2333 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2334 guarantee(_source_debug_extension == NULL, "must be");
2335 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2336 guarantee(_osr_nmethods_head == NULL, "must be");
2337
2338 #if INCLUDE_JVMTI
2339 guarantee(_breakpoints == NULL, "must be");
2340 guarantee(_previous_versions == NULL, "must be");
2341 #endif
2342
2343 _init_thread = NULL;
2344 _methods_jmethod_ids = NULL;
2345 _jni_ids = NULL;
2346 _oop_map_cache = NULL;
2347 // clear _nest_host to ensure re-load at runtime
2348 _nest_host = NULL;
2349 }
2350
2351 void InstanceKlass::remove_java_mirror() {
2352 Klass::remove_java_mirror();
2353
2354 // do array classes also.
2355 if (array_klasses() != NULL) {
2356 array_klasses()->remove_java_mirror();
2357 }
2358 }
2359
2360 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2361 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2362 // before the InstanceKlass is added to the SystemDictionary. Make
2363 // sure the current state is <loaded.
2364 assert(!is_loaded(), "invalid init state");
2365 set_package(loader_data, CHECK);
2366 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2367
2368 Array<Method*>* methods = this->methods();
2369 int num_methods = methods->length();
2370 for (int index2 = 0; index2 < num_methods; ++index2) {
2371 methodHandle m(THREAD, methods->at(index2));
2372 m->restore_unshareable_info(CHECK);
2373 }
2374 if (JvmtiExport::has_redefined_a_class()) {
2375 // Reinitialize vtable because RedefineClasses may have changed some
2376 // entries in this vtable for super classes so the CDS vtable might
2377 // point to old or obsolete entries. RedefineClasses doesn't fix up
2378 // vtables in the shared system dictionary, only the main one.
2379 // It also redefines the itable too so fix that too.
2380 vtable().initialize_vtable(false, CHECK);
2381 itable().initialize_itable(false, CHECK);
2382 }
2383
2384 // restore constant pool resolved references
2385 constants()->restore_unshareable_info(CHECK);
2386
2387 if (array_klasses() != NULL) {
2388 // Array classes have null protection domain.
2389 // --> see ArrayKlass::complete_create_array_klass()
2390 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2391 }
2392 }
2393
2394 // returns true IFF is_in_error_state() has been changed as a result of this call.
2395 bool InstanceKlass::check_sharing_error_state() {
2396 assert(DumpSharedSpaces, "should only be called during dumping");
2397 bool old_state = is_in_error_state();
2398
2399 if (!is_in_error_state()) {
2400 bool bad = false;
2401 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2402 if (sup->is_in_error_state()) {
2403 bad = true;
2404 break;
2405 }
2406 }
2407 if (!bad) {
2408 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2409 for (int i = 0; i < interfaces->length(); i++) {
2410 InstanceKlass* iface = interfaces->at(i);
2411 if (iface->is_in_error_state()) {
2412 bad = true;
2413 break;
2414 }
2415 }
2416 }
2417
2418 if (bad) {
2419 set_in_error_state();
2420 }
2421 }
2422
2423 return (old_state != is_in_error_state());
2424 }
2425
2426 #if INCLUDE_JVMTI
2427 static void clear_all_breakpoints(Method* m) {
2428 m->clear_all_breakpoints();
2429 }
2430 #endif
2431
2432 void InstanceKlass::unload_class(InstanceKlass* ik) {
2433 // Release dependencies.
2434 ik->dependencies().remove_all_dependents();
2435
2436 // notify the debugger
2437 if (JvmtiExport::should_post_class_unload()) {
2438 JvmtiExport::post_class_unload(ik);
2439 }
2440
2441 // notify ClassLoadingService of class unload
2442 ClassLoadingService::notify_class_unloaded(ik);
2443
2444 #if INCLUDE_JFR
2445 assert(ik != NULL, "invariant");
2446 EventClassUnload event;
2447 event.set_unloadedClass(ik);
2448 event.set_definingClassLoader(ik->class_loader_data());
2449 event.commit();
2450 #endif
2451 }
2452
2453 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2454 // Clean up C heap
2455 ik->release_C_heap_structures();
2456 ik->constants()->release_C_heap_structures();
2457 }
2458
2459 void InstanceKlass::release_C_heap_structures() {
2460 // Can't release the constant pool here because the constant pool can be
2461 // deallocated separately from the InstanceKlass for default methods and
2462 // redefine classes.
2463
2464 // Deallocate oop map cache
2465 if (_oop_map_cache != NULL) {
2466 delete _oop_map_cache;
2467 _oop_map_cache = NULL;
2468 }
2469
2470 // Deallocate JNI identifiers for jfieldIDs
2471 JNIid::deallocate(jni_ids());
2472 set_jni_ids(NULL);
2473
2474 jmethodID* jmeths = methods_jmethod_ids_acquire();
2475 if (jmeths != (jmethodID*)NULL) {
2476 release_set_methods_jmethod_ids(NULL);
2477 FreeHeap(jmeths);
2478 }
2479
2480 assert(_dep_context == DependencyContext::EMPTY,
2481 "dependencies should already be cleaned");
2482
2483 #if INCLUDE_JVMTI
2484 // Deallocate breakpoint records
2485 if (breakpoints() != 0x0) {
2486 methods_do(clear_all_breakpoints);
2487 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2488 }
2489
2490 // deallocate the cached class file
2491 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2492 os::free(_cached_class_file);
2493 _cached_class_file = NULL;
2494 }
2495 #endif
2496
2497 // Decrement symbol reference counts associated with the unloaded class.
2498 if (_name != NULL) _name->decrement_refcount();
2499 // unreference array name derived from this class name (arrays of an unloaded
2500 // class can't be referenced anymore).
2501 if (_array_name != NULL) _array_name->decrement_refcount();
2502 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2503 }
2504
2505 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2506 if (array == NULL) {
2507 _source_debug_extension = NULL;
2508 } else {
2509 // Adding one to the attribute length in order to store a null terminator
2510 // character could cause an overflow because the attribute length is
2511 // already coded with an u4 in the classfile, but in practice, it's
2512 // unlikely to happen.
2513 assert((length+1) > length, "Overflow checking");
2514 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2515 for (int i = 0; i < length; i++) {
2516 sde[i] = array[i];
2517 }
2518 sde[length] = '\0';
2519 _source_debug_extension = sde;
2520 }
2521 }
2522
2523 const char* InstanceKlass::signature_name() const {
2524 int hash_len = 0;
2525 char hash_buf[40];
2526
2527 // If this is an unsafe anonymous class, append a hash to make the name unique
2528 if (is_unsafe_anonymous()) {
2529 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2530 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2531 hash_len = (int)strlen(hash_buf);
2532 }
2533
2534 // Get the internal name as a c string
2535 const char* src = (const char*) (name()->as_C_string());
2536 const int src_length = (int)strlen(src);
2537
2538 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2539
2540 // Add L as type indicator
2541 int dest_index = 0;
2542 dest[dest_index++] = 'L';
2543
2544 // Add the actual class name
2545 for (int src_index = 0; src_index < src_length; ) {
2546 dest[dest_index++] = src[src_index++];
2547 }
2548
2549 // If we have a hash, append it
2550 for (int hash_index = 0; hash_index < hash_len; ) {
2551 dest[dest_index++] = hash_buf[hash_index++];
2552 }
2553
2554 // Add the semicolon and the NULL
2555 dest[dest_index++] = ';';
2556 dest[dest_index] = '\0';
2557 return dest;
2558 }
2559
2560 // Used to obtain the package name from a fully qualified class name.
2561 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2562 if (name == NULL) {
2563 return NULL;
2564 } else {
2565 if (name->utf8_length() <= 0) {
2566 return NULL;
2567 }
2568 ResourceMark rm;
2569 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2570 if (package_name == NULL) {
2571 return NULL;
2572 }
2573 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2574 return pkg_name;
2575 }
2576 }
2577
2578 ModuleEntry* InstanceKlass::module() const {
2579 // For an unsafe anonymous class return the host class' module
2580 if (is_unsafe_anonymous()) {
2581 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2582 return unsafe_anonymous_host()->module();
2583 }
2584
2585 // Class is in a named package
2586 if (!in_unnamed_package()) {
2587 return _package_entry->module();
2588 }
2589
2590 // Class is in an unnamed package, return its loader's unnamed module
2591 return class_loader_data()->unnamed_module();
2592 }
2593
2594 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2595
2596 // ensure java/ packages only loaded by boot or platform builtin loaders
2597 check_prohibited_package(name(), loader_data, CHECK);
2598
2599 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2600
2601 if (pkg_name != NULL && loader_data != NULL) {
2602
2603 // Find in class loader's package entry table.
2604 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2605
2606 // If the package name is not found in the loader's package
2607 // entry table, it is an indication that the package has not
2608 // been defined. Consider it defined within the unnamed module.
2609 if (_package_entry == NULL) {
2610 ResourceMark rm;
2611
2612 if (!ModuleEntryTable::javabase_defined()) {
2613 // Before java.base is defined during bootstrapping, define all packages in
2614 // the java.base module. If a non-java.base package is erroneously placed
2615 // in the java.base module it will be caught later when java.base
2616 // is defined by ModuleEntryTable::verify_javabase_packages check.
2617 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2618 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2619 } else {
2620 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2621 _package_entry = loader_data->packages()->lookup(pkg_name,
2622 loader_data->unnamed_module());
2623 }
2624
2625 // A package should have been successfully created
2626 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2627 name()->as_C_string(), loader_data->loader_name_and_id());
2628 }
2629
2630 if (log_is_enabled(Debug, module)) {
2631 ResourceMark rm;
2632 ModuleEntry* m = _package_entry->module();
2633 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2634 external_name(),
2635 pkg_name->as_C_string(),
2636 loader_data->loader_name_and_id(),
2637 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2638 }
2639 } else {
2640 ResourceMark rm;
2641 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2642 external_name(),
2643 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2644 UNNAMED_MODULE);
2645 }
2646 }
2647
2648
2649 // different versions of is_same_class_package
2650
2651 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2652 oop classloader1 = this->class_loader();
2653 PackageEntry* classpkg1 = this->package();
2654 if (class2->is_objArray_klass()) {
2655 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2656 }
2657
2658 oop classloader2;
2659 PackageEntry* classpkg2;
2660 if (class2->is_instance_klass()) {
2661 classloader2 = class2->class_loader();
2662 classpkg2 = class2->package();
2663 } else {
2664 assert(class2->is_typeArray_klass(), "should be type array");
2665 classloader2 = NULL;
2666 classpkg2 = NULL;
2667 }
2668
2669 // Same package is determined by comparing class loader
2670 // and package entries. Both must be the same. This rule
2671 // applies even to classes that are defined in the unnamed
2672 // package, they still must have the same class loader.
2673 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2674 return true;
2675 }
2676
2677 return false;
2678 }
2679
2680 // return true if this class and other_class are in the same package. Classloader
2681 // and classname information is enough to determine a class's package
2682 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2683 const Symbol* other_class_name) const {
2684 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2685 return false;
2686 }
2687 if (name()->fast_compare(other_class_name) == 0) {
2688 return true;
2689 }
2690
2691 {
2692 ResourceMark rm;
2693
2694 bool bad_class_name = false;
2695 const char* other_pkg =
2696 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2697 if (bad_class_name) {
2698 return false;
2699 }
2700 // Check that package_from_name() returns NULL, not "", if there is no package.
2701 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2702
2703 const Symbol* const this_package_name =
2704 this->package() != NULL ? this->package()->name() : NULL;
2705
2706 if (this_package_name == NULL || other_pkg == NULL) {
2707 // One of the two doesn't have a package. Only return true if the other
2708 // one also doesn't have a package.
2709 return (const char*)this_package_name == other_pkg;
2710 }
2711
2712 // Check if package is identical
2713 return this_package_name->equals(other_pkg);
2714 }
2715 }
2716
2717 // Returns true iff super_method can be overridden by a method in targetclassname
2718 // See JLS 3rd edition 8.4.6.1
2719 // Assumes name-signature match
2720 // "this" is InstanceKlass of super_method which must exist
2721 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2722 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2723 // Private methods can not be overridden
2724 if (super_method->is_private()) {
2725 return false;
2726 }
2727 // If super method is accessible, then override
2728 if ((super_method->is_protected()) ||
2729 (super_method->is_public())) {
2730 return true;
2731 }
2732 // Package-private methods are not inherited outside of package
2733 assert(super_method->is_package_private(), "must be package private");
2734 return(is_same_class_package(targetclassloader(), targetclassname));
2735 }
2736
2737 // Only boot and platform class loaders can define classes in "java/" packages.
2738 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2739 ClassLoaderData* loader_data,
2740 TRAPS) {
2741 if (!loader_data->is_boot_class_loader_data() &&
2742 !loader_data->is_platform_class_loader_data() &&
2743 class_name != NULL) {
2744 ResourceMark rm(THREAD);
2745 char* name = class_name->as_C_string();
2746 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2747 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2748 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2749 name = pkg_name->as_C_string();
2750 const char* class_loader_name = loader_data->loader_name_and_id();
2751 StringUtils::replace_no_expand(name, "/", ".");
2752 const char* msg_text1 = "Class loader (instance of): ";
2753 const char* msg_text2 = " tried to load prohibited package name: ";
2754 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2755 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2756 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2757 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2758 }
2759 }
2760 return;
2761 }
2762
2763 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2764 constantPoolHandle i_cp(THREAD, constants());
2765 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2766 int ioff = iter.inner_class_info_index();
2767 if (ioff != 0) {
2768 // Check to see if the name matches the class we're looking for
2769 // before attempting to find the class.
2770 if (i_cp->klass_name_at_matches(this, ioff)) {
2771 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2772 if (this == inner_klass) {
2773 *ooff = iter.outer_class_info_index();
2774 *noff = iter.inner_name_index();
2775 return true;
2776 }
2777 }
2778 }
2779 }
2780 return false;
2781 }
2782
2783 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2784 InstanceKlass* outer_klass = NULL;
2785 *inner_is_member = false;
2786 int ooff = 0, noff = 0;
2787 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2788 if (has_inner_classes_attr) {
2789 constantPoolHandle i_cp(THREAD, constants());
2790 if (ooff != 0) {
2791 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2792 outer_klass = InstanceKlass::cast(ok);
2793 *inner_is_member = true;
2794 }
2795 if (NULL == outer_klass) {
2796 // It may be unsafe anonymous; try for that.
2797 int encl_method_class_idx = enclosing_method_class_index();
2798 if (encl_method_class_idx != 0) {
2799 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2800 outer_klass = InstanceKlass::cast(ok);
2801 *inner_is_member = false;
2802 }
2803 }
2804 }
2805
2806 // If no inner class attribute found for this class.
2807 if (NULL == outer_klass) return NULL;
2808
2809 // Throws an exception if outer klass has not declared k as an inner klass
2810 // We need evidence that each klass knows about the other, or else
2811 // the system could allow a spoof of an inner class to gain access rights.
2812 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2813 return outer_klass;
2814 }
2815
2816 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2817 jint access = access_flags().as_int();
2818
2819 // But check if it happens to be member class.
2820 InnerClassesIterator iter(this);
2821 for (; !iter.done(); iter.next()) {
2822 int ioff = iter.inner_class_info_index();
2823 // Inner class attribute can be zero, skip it.
2824 // Strange but true: JVM spec. allows null inner class refs.
2825 if (ioff == 0) continue;
2826
2827 // only look at classes that are already loaded
2828 // since we are looking for the flags for our self.
2829 Symbol* inner_name = constants()->klass_name_at(ioff);
2830 if (name() == inner_name) {
2831 // This is really a member class.
2832 access = iter.inner_access_flags();
2833 break;
2834 }
2835 }
2836 // Remember to strip ACC_SUPER bit
2837 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2838 }
2839
2840 jint InstanceKlass::jvmti_class_status() const {
2841 jint result = 0;
2842
2843 if (is_linked()) {
2844 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2845 }
2846
2847 if (is_initialized()) {
2848 assert(is_linked(), "Class status is not consistent");
2849 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2850 }
2851 if (is_in_error_state()) {
2852 result |= JVMTI_CLASS_STATUS_ERROR;
2853 }
2854 return result;
2855 }
2856
2857 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2858 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2859 int method_table_offset_in_words = ioe->offset()/wordSize;
2860 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2861 / itableOffsetEntry::size();
2862
2863 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2864 // If the interface isn't implemented by the receiver class,
2865 // the VM should throw IncompatibleClassChangeError.
2866 if (cnt >= nof_interfaces) {
2867 ResourceMark rm(THREAD);
2868 stringStream ss;
2869 bool same_module = (module() == holder->module());
2870 ss.print("Receiver class %s does not implement "
2871 "the interface %s defining the method to be called "
2872 "(%s%s%s)",
2873 external_name(), holder->external_name(),
2874 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2875 (same_module) ? "" : "; ",
2876 (same_module) ? "" : holder->class_in_module_of_loader());
2877 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2878 }
2879
2880 Klass* ik = ioe->interface_klass();
2881 if (ik == holder) break;
2882 }
2883
2884 itableMethodEntry* ime = ioe->first_method_entry(this);
2885 Method* m = ime[index].method();
2886 if (m == NULL) {
2887 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2888 }
2889 return m;
2890 }
2891
2892
2893 #if INCLUDE_JVMTI
2894 // update default_methods for redefineclasses for methods that are
2895 // not yet in the vtable due to concurrent subclass define and superinterface
2896 // redefinition
2897 // Note: those in the vtable, should have been updated via adjust_method_entries
2898 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2899 // search the default_methods for uses of either obsolete or EMCP methods
2900 if (default_methods() != NULL) {
2901 for (int index = 0; index < default_methods()->length(); index ++) {
2902 Method* old_method = default_methods()->at(index);
2903 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2904 continue; // skip uninteresting entries
2905 }
2906 assert(!old_method->is_deleted(), "default methods may not be deleted");
2907
2908 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2909
2910 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2911 assert(old_method != new_method, "sanity check");
2912
2913 default_methods()->at_put(index, new_method);
2914 if (log_is_enabled(Info, redefine, class, update)) {
2915 ResourceMark rm;
2916 if (!(*trace_name_printed)) {
2917 log_info(redefine, class, update)
2918 ("adjust: klassname=%s default methods from name=%s",
2919 external_name(), old_method->method_holder()->external_name());
2920 *trace_name_printed = true;
2921 }
2922 log_debug(redefine, class, update, vtables)
2923 ("default method update: %s(%s) ",
2924 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2925 }
2926 }
2927 }
2928 }
2929 #endif // INCLUDE_JVMTI
2930
2931 // On-stack replacement stuff
2932 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2933 // only one compilation can be active
2934 {
2935 // This is a short non-blocking critical region, so the no safepoint check is ok.
2936 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2937 assert(n->is_osr_method(), "wrong kind of nmethod");
2938 n->set_osr_link(osr_nmethods_head());
2939 set_osr_nmethods_head(n);
2940 // Raise the highest osr level if necessary
2941 if (TieredCompilation) {
2942 Method* m = n->method();
2943 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2944 }
2945 }
2946
2947 // Get rid of the osr methods for the same bci that have lower levels.
2948 if (TieredCompilation) {
2949 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2950 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2951 if (inv != NULL && inv->is_in_use()) {
2952 inv->make_not_entrant();
2953 }
2954 }
2955 }
2956 }
2957
2958 // Remove osr nmethod from the list. Return true if found and removed.
2959 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2960 // This is a short non-blocking critical region, so the no safepoint check is ok.
2961 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2962 assert(n->is_osr_method(), "wrong kind of nmethod");
2963 nmethod* last = NULL;
2964 nmethod* cur = osr_nmethods_head();
2965 int max_level = CompLevel_none; // Find the max comp level excluding n
2966 Method* m = n->method();
2967 // Search for match
2968 bool found = false;
2969 while(cur != NULL && cur != n) {
2970 if (TieredCompilation && m == cur->method()) {
2971 // Find max level before n
2972 max_level = MAX2(max_level, cur->comp_level());
2973 }
2974 last = cur;
2975 cur = cur->osr_link();
2976 }
2977 nmethod* next = NULL;
2978 if (cur == n) {
2979 found = true;
2980 next = cur->osr_link();
2981 if (last == NULL) {
2982 // Remove first element
2983 set_osr_nmethods_head(next);
2984 } else {
2985 last->set_osr_link(next);
2986 }
2987 }
2988 n->set_osr_link(NULL);
2989 if (TieredCompilation) {
2990 cur = next;
2991 while (cur != NULL) {
2992 // Find max level after n
2993 if (m == cur->method()) {
2994 max_level = MAX2(max_level, cur->comp_level());
2995 }
2996 cur = cur->osr_link();
2997 }
2998 m->set_highest_osr_comp_level(max_level);
2999 }
3000 return found;
3001 }
3002
3003 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3004 // This is a short non-blocking critical region, so the no safepoint check is ok.
3005 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3006 nmethod* osr = osr_nmethods_head();
3007 int found = 0;
3008 while (osr != NULL) {
3009 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3010 if (osr->method() == m) {
3011 osr->mark_for_deoptimization();
3012 found++;
3013 }
3014 osr = osr->osr_link();
3015 }
3016 return found;
3017 }
3018
3019 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3020 // This is a short non-blocking critical region, so the no safepoint check is ok.
3021 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3022 nmethod* osr = osr_nmethods_head();
3023 nmethod* best = NULL;
3024 while (osr != NULL) {
3025 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3026 // There can be a time when a c1 osr method exists but we are waiting
3027 // for a c2 version. When c2 completes its osr nmethod we will trash
3028 // the c1 version and only be able to find the c2 version. However
3029 // while we overflow in the c1 code at back branches we don't want to
3030 // try and switch to the same code as we are already running
3031
3032 if (osr->method() == m &&
3033 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3034 if (match_level) {
3035 if (osr->comp_level() == comp_level) {
3036 // Found a match - return it.
3037 return osr;
3038 }
3039 } else {
3040 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3041 if (osr->comp_level() == CompLevel_highest_tier) {
3042 // Found the best possible - return it.
3043 return osr;
3044 }
3045 best = osr;
3046 }
3047 }
3048 }
3049 osr = osr->osr_link();
3050 }
3051 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3052 return best;
3053 }
3054 return NULL;
3055 }
3056
3057 // -----------------------------------------------------------------------------------------------------
3058 // Printing
3059
3060 #ifndef PRODUCT
3061
3062 #define BULLET " - "
3063
3064 static const char* state_names[] = {
3065 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3066 };
3067
3068 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3069 for (int i = 0; i < len; i++) {
3070 intptr_t e = start[i];
3071 st->print("%d : " INTPTR_FORMAT, i, e);
3072 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3073 st->print(" ");
3074 ((Metadata*)e)->print_value_on(st);
3075 }
3076 st->cr();
3077 }
3078 }
3079
3080 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3081 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3082 }
3083
3084 void InstanceKlass::print_on(outputStream* st) const {
3085 assert(is_klass(), "must be klass");
3086 Klass::print_on(st);
3087
3088 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3089 st->print(BULLET"klass size: %d", size()); st->cr();
3090 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3091 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3092 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3093 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3094 st->print(BULLET"sub: ");
3095 Klass* sub = subklass();
3096 int n;
3097 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3098 if (n < MaxSubklassPrintSize) {
3099 sub->print_value_on(st);
3100 st->print(" ");
3101 }
3102 }
3103 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3104 st->cr();
3105
3106 if (is_interface()) {
3107 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3108 if (nof_implementors() == 1) {
3109 st->print_cr(BULLET"implementor: ");
3110 st->print(" ");
3111 implementor()->print_value_on(st);
3112 st->cr();
3113 }
3114 }
3115
3116 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3117 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3118 if (Verbose || WizardMode) {
3119 Array<Method*>* method_array = methods();
3120 for (int i = 0; i < method_array->length(); i++) {
3121 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3122 }
3123 }
3124 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3125 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3126 if (Verbose && default_methods() != NULL) {
3127 Array<Method*>* method_array = default_methods();
3128 for (int i = 0; i < method_array->length(); i++) {
3129 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3130 }
3131 }
3132 if (default_vtable_indices() != NULL) {
3133 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3134 }
3135 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3136 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3137 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3138 if (class_loader_data() != NULL) {
3139 st->print(BULLET"class loader data: ");
3140 class_loader_data()->print_value_on(st);
3141 st->cr();
3142 }
3143 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3144 if (source_file_name() != NULL) {
3145 st->print(BULLET"source file: ");
3146 source_file_name()->print_value_on(st);
3147 st->cr();
3148 }
3149 if (source_debug_extension() != NULL) {
3150 st->print(BULLET"source debug extension: ");
3151 st->print("%s", source_debug_extension());
3152 st->cr();
3153 }
3154 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3155 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3156 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3157 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3158 {
3159 bool have_pv = false;
3160 // previous versions are linked together through the InstanceKlass
3161 for (InstanceKlass* pv_node = previous_versions();
3162 pv_node != NULL;
3163 pv_node = pv_node->previous_versions()) {
3164 if (!have_pv)
3165 st->print(BULLET"previous version: ");
3166 have_pv = true;
3167 pv_node->constants()->print_value_on(st);
3168 }
3169 if (have_pv) st->cr();
3170 }
3171
3172 if (generic_signature() != NULL) {
3173 st->print(BULLET"generic signature: ");
3174 generic_signature()->print_value_on(st);
3175 st->cr();
3176 }
3177 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3178 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3179 if (java_mirror() != NULL) {
3180 st->print(BULLET"java mirror: ");
3181 java_mirror()->print_value_on(st);
3182 st->cr();
3183 } else {
3184 st->print_cr(BULLET"java mirror: NULL");
3185 }
3186 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3187 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3188 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3189 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3190 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3191 FieldPrinter print_static_field(st);
3192 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3193 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3194 FieldPrinter print_nonstatic_field(st);
3195 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3196 ik->do_nonstatic_fields(&print_nonstatic_field);
3197
3198 st->print(BULLET"non-static oop maps: ");
3199 OopMapBlock* map = start_of_nonstatic_oop_maps();
3200 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3201 while (map < end_map) {
3202 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3203 map++;
3204 }
3205 st->cr();
3206 }
3207
3208 #endif //PRODUCT
3209
3210 void InstanceKlass::print_value_on(outputStream* st) const {
3211 assert(is_klass(), "must be klass");
3212 if (Verbose || WizardMode) access_flags().print_on(st);
3213 name()->print_value_on(st);
3214 }
3215
3216 #ifndef PRODUCT
3217
3218 void FieldPrinter::do_field(fieldDescriptor* fd) {
3219 _st->print(BULLET);
3220 if (_obj == NULL) {
3221 fd->print_on(_st);
3222 _st->cr();
3223 } else {
3224 fd->print_on_for(_st, _obj);
3225 _st->cr();
3226 }
3227 }
3228
3229
3230 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3231 Klass::oop_print_on(obj, st);
3232
3233 if (this == SystemDictionary::String_klass()) {
3234 typeArrayOop value = java_lang_String::value(obj);
3235 juint length = java_lang_String::length(obj);
3236 if (value != NULL &&
3237 value->is_typeArray() &&
3238 length <= (juint) value->length()) {
3239 st->print(BULLET"string: ");
3240 java_lang_String::print(obj, st);
3241 st->cr();
3242 if (!WizardMode) return; // that is enough
3243 }
3244 }
3245
3246 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3247 FieldPrinter print_field(st, obj);
3248 do_nonstatic_fields(&print_field);
3249
3250 if (this == SystemDictionary::Class_klass()) {
3251 st->print(BULLET"signature: ");
3252 java_lang_Class::print_signature(obj, st);
3253 st->cr();
3254 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3255 st->print(BULLET"fake entry for mirror: ");
3256 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3257 st->cr();
3258 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3259 st->print(BULLET"fake entry for array: ");
3260 Metadata::print_value_on_maybe_null(st, array_klass);
3261 st->cr();
3262 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3263 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3264 Klass* real_klass = java_lang_Class::as_Klass(obj);
3265 if (real_klass != NULL && real_klass->is_instance_klass()) {
3266 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3267 }
3268 } else if (this == SystemDictionary::MethodType_klass()) {
3269 st->print(BULLET"signature: ");
3270 java_lang_invoke_MethodType::print_signature(obj, st);
3271 st->cr();
3272 }
3273 }
3274
3275 bool InstanceKlass::verify_itable_index(int i) {
3276 int method_count = klassItable::method_count_for_interface(this);
3277 assert(i >= 0 && i < method_count, "index out of bounds");
3278 return true;
3279 }
3280
3281 #endif //PRODUCT
3282
3283 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3284 st->print("a ");
3285 name()->print_value_on(st);
3286 obj->print_address_on(st);
3287 if (this == SystemDictionary::String_klass()
3288 && java_lang_String::value(obj) != NULL) {
3289 ResourceMark rm;
3290 int len = java_lang_String::length(obj);
3291 int plen = (len < 24 ? len : 12);
3292 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3293 st->print(" = \"%s\"", str);
3294 if (len > plen)
3295 st->print("...[%d]", len);
3296 } else if (this == SystemDictionary::Class_klass()) {
3297 Klass* k = java_lang_Class::as_Klass(obj);
3298 st->print(" = ");
3299 if (k != NULL) {
3300 k->print_value_on(st);
3301 } else {
3302 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3303 st->print("%s", tname ? tname : "type?");
3304 }
3305 } else if (this == SystemDictionary::MethodType_klass()) {
3306 st->print(" = ");
3307 java_lang_invoke_MethodType::print_signature(obj, st);
3308 } else if (java_lang_boxing_object::is_instance(obj)) {
3309 st->print(" = ");
3310 java_lang_boxing_object::print(obj, st);
3311 } else if (this == SystemDictionary::LambdaForm_klass()) {
3312 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3313 if (vmentry != NULL) {
3314 st->print(" => ");
3315 vmentry->print_value_on(st);
3316 }
3317 } else if (this == SystemDictionary::MemberName_klass()) {
3318 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3319 if (vmtarget != NULL) {
3320 st->print(" = ");
3321 vmtarget->print_value_on(st);
3322 } else {
3323 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3324 st->print(".");
3325 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3326 }
3327 }
3328 }
3329
3330 const char* InstanceKlass::internal_name() const {
3331 return external_name();
3332 }
3333
3334 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3335 const char* module_name,
3336 const ClassFileStream* cfs) const {
3337 if (!log_is_enabled(Info, class, load)) {
3338 return;
3339 }
3340
3341 ResourceMark rm;
3342 LogMessage(class, load) msg;
3343 stringStream info_stream;
3344
3345 // Name and class hierarchy info
3346 info_stream.print("%s", external_name());
3347
3348 // Source
3349 if (cfs != NULL) {
3350 if (cfs->source() != NULL) {
3351 if (module_name != NULL) {
3352 if (ClassLoader::is_modules_image(cfs->source())) {
3353 info_stream.print(" source: jrt:/%s", module_name);
3354 } else {
3355 info_stream.print(" source: %s", cfs->source());
3356 }
3357 } else {
3358 info_stream.print(" source: %s", cfs->source());
3359 }
3360 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3361 Thread* THREAD = Thread::current();
3362 Klass* caller =
3363 THREAD->is_Java_thread()
3364 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3365 : NULL;
3366 // caller can be NULL, for example, during a JVMTI VM_Init hook
3367 if (caller != NULL) {
3368 info_stream.print(" source: instance of %s", caller->external_name());
3369 } else {
3370 // source is unknown
3371 }
3372 } else {
3373 oop class_loader = loader_data->class_loader();
3374 info_stream.print(" source: %s", class_loader->klass()->external_name());
3375 }
3376 } else {
3377 info_stream.print(" source: shared objects file");
3378 }
3379
3380 msg.info("%s", info_stream.as_string());
3381
3382 if (log_is_enabled(Debug, class, load)) {
3383 stringStream debug_stream;
3384
3385 // Class hierarchy info
3386 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3387 p2i(this), p2i(superklass()));
3388
3389 // Interfaces
3390 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3391 debug_stream.print(" interfaces:");
3392 int length = local_interfaces()->length();
3393 for (int i = 0; i < length; i++) {
3394 debug_stream.print(" " INTPTR_FORMAT,
3395 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3396 }
3397 }
3398
3399 // Class loader
3400 debug_stream.print(" loader: [");
3401 loader_data->print_value_on(&debug_stream);
3402 debug_stream.print("]");
3403
3404 // Classfile checksum
3405 if (cfs) {
3406 debug_stream.print(" bytes: %d checksum: %08x",
3407 cfs->length(),
3408 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3409 cfs->length()));
3410 }
3411
3412 msg.debug("%s", debug_stream.as_string());
3413 }
3414 }
3415
3416 #if INCLUDE_SERVICES
3417 // Size Statistics
3418 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3419 Klass::collect_statistics(sz);
3420
3421 sz->_inst_size = wordSize * size_helper();
3422 sz->_vtab_bytes = wordSize * vtable_length();
3423 sz->_itab_bytes = wordSize * itable_length();
3424 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3425
3426 int n = 0;
3427 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3428 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3429 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3430 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3431 n += (sz->_fields_bytes = sz->count_array(fields()));
3432 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3433 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3434 sz->_ro_bytes += n;
3435
3436 const ConstantPool* cp = constants();
3437 if (cp) {
3438 cp->collect_statistics(sz);
3439 }
3440
3441 const Annotations* anno = annotations();
3442 if (anno) {
3443 anno->collect_statistics(sz);
3444 }
3445
3446 const Array<Method*>* methods_array = methods();
3447 if (methods()) {
3448 for (int i = 0; i < methods_array->length(); i++) {
3449 Method* method = methods_array->at(i);
3450 if (method) {
3451 sz->_method_count ++;
3452 method->collect_statistics(sz);
3453 }
3454 }
3455 }
3456 }
3457 #endif // INCLUDE_SERVICES
3458
3459 // Verification
3460
3461 class VerifyFieldClosure: public BasicOopIterateClosure {
3462 protected:
3463 template <class T> void do_oop_work(T* p) {
3464 oop obj = RawAccess<>::oop_load(p);
3465 if (!oopDesc::is_oop_or_null(obj)) {
3466 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3467 Universe::print_on(tty);
3468 guarantee(false, "boom");
3469 }
3470 }
3471 public:
3472 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3473 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3474 };
3475
3476 void InstanceKlass::verify_on(outputStream* st) {
3477 #ifndef PRODUCT
3478 // Avoid redundant verifies, this really should be in product.
3479 if (_verify_count == Universe::verify_count()) return;
3480 _verify_count = Universe::verify_count();
3481 #endif
3482
3483 // Verify Klass
3484 Klass::verify_on(st);
3485
3486 // Verify that klass is present in ClassLoaderData
3487 guarantee(class_loader_data()->contains_klass(this),
3488 "this class isn't found in class loader data");
3489
3490 // Verify vtables
3491 if (is_linked()) {
3492 // $$$ This used to be done only for m/s collections. Doing it
3493 // always seemed a valid generalization. (DLD -- 6/00)
3494 vtable().verify(st);
3495 }
3496
3497 // Verify first subklass
3498 if (subklass() != NULL) {
3499 guarantee(subklass()->is_klass(), "should be klass");
3500 }
3501
3502 // Verify siblings
3503 Klass* super = this->super();
3504 Klass* sib = next_sibling();
3505 if (sib != NULL) {
3506 if (sib == this) {
3507 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3508 }
3509
3510 guarantee(sib->is_klass(), "should be klass");
3511 guarantee(sib->super() == super, "siblings should have same superklass");
3512 }
3513
3514 // Verify local interfaces
3515 if (local_interfaces()) {
3516 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3517 for (int j = 0; j < local_interfaces->length(); j++) {
3518 InstanceKlass* e = local_interfaces->at(j);
3519 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3520 }
3521 }
3522
3523 // Verify transitive interfaces
3524 if (transitive_interfaces() != NULL) {
3525 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3526 for (int j = 0; j < transitive_interfaces->length(); j++) {
3527 InstanceKlass* e = transitive_interfaces->at(j);
3528 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3529 }
3530 }
3531
3532 // Verify methods
3533 if (methods() != NULL) {
3534 Array<Method*>* methods = this->methods();
3535 for (int j = 0; j < methods->length(); j++) {
3536 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3537 }
3538 for (int j = 0; j < methods->length() - 1; j++) {
3539 Method* m1 = methods->at(j);
3540 Method* m2 = methods->at(j + 1);
3541 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3542 }
3543 }
3544
3545 // Verify method ordering
3546 if (method_ordering() != NULL) {
3547 Array<int>* method_ordering = this->method_ordering();
3548 int length = method_ordering->length();
3549 if (JvmtiExport::can_maintain_original_method_order() ||
3550 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3551 guarantee(length == methods()->length(), "invalid method ordering length");
3552 jlong sum = 0;
3553 for (int j = 0; j < length; j++) {
3554 int original_index = method_ordering->at(j);
3555 guarantee(original_index >= 0, "invalid method ordering index");
3556 guarantee(original_index < length, "invalid method ordering index");
3557 sum += original_index;
3558 }
3559 // Verify sum of indices 0,1,...,length-1
3560 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3561 } else {
3562 guarantee(length == 0, "invalid method ordering length");
3563 }
3564 }
3565
3566 // Verify default methods
3567 if (default_methods() != NULL) {
3568 Array<Method*>* methods = this->default_methods();
3569 for (int j = 0; j < methods->length(); j++) {
3570 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3571 }
3572 for (int j = 0; j < methods->length() - 1; j++) {
3573 Method* m1 = methods->at(j);
3574 Method* m2 = methods->at(j + 1);
3575 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3576 }
3577 }
3578
3579 // Verify JNI static field identifiers
3580 if (jni_ids() != NULL) {
3581 jni_ids()->verify(this);
3582 }
3583
3584 // Verify other fields
3585 if (array_klasses() != NULL) {
3586 guarantee(array_klasses()->is_klass(), "should be klass");
3587 }
3588 if (constants() != NULL) {
3589 guarantee(constants()->is_constantPool(), "should be constant pool");
3590 }
3591 const Klass* anonymous_host = unsafe_anonymous_host();
3592 if (anonymous_host != NULL) {
3593 guarantee(anonymous_host->is_klass(), "should be klass");
3594 }
3595 }
3596
3597 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3598 Klass::oop_verify_on(obj, st);
3599 VerifyFieldClosure blk;
3600 obj->oop_iterate(&blk);
3601 }
3602
3603
3604 // JNIid class for jfieldIDs only
3605 // Note to reviewers:
3606 // These JNI functions are just moved over to column 1 and not changed
3607 // in the compressed oops workspace.
3608 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3609 _holder = holder;
3610 _offset = offset;
3611 _next = next;
3612 debug_only(_is_static_field_id = false;)
3613 }
3614
3615
3616 JNIid* JNIid::find(int offset) {
3617 JNIid* current = this;
3618 while (current != NULL) {
3619 if (current->offset() == offset) return current;
3620 current = current->next();
3621 }
3622 return NULL;
3623 }
3624
3625 void JNIid::deallocate(JNIid* current) {
3626 while (current != NULL) {
3627 JNIid* next = current->next();
3628 delete current;
3629 current = next;
3630 }
3631 }
3632
3633
3634 void JNIid::verify(Klass* holder) {
3635 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3636 int end_field_offset;
3637 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3638
3639 JNIid* current = this;
3640 while (current != NULL) {
3641 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3642 #ifdef ASSERT
3643 int o = current->offset();
3644 if (current->is_static_field_id()) {
3645 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3646 }
3647 #endif
3648 current = current->next();
3649 }
3650 }
3651
3652 #ifdef ASSERT
3653 void InstanceKlass::set_init_state(ClassState state) {
3654 bool good_state = is_shared() ? (_init_state <= state)
3655 : (_init_state < state);
3656 assert(good_state || state == allocated, "illegal state transition");
3657 _init_state = (u1)state;
3658 }
3659 #endif
3660
3661 #if INCLUDE_JVMTI
3662
3663 // RedefineClasses() support for previous versions
3664
3665 // Globally, there is at least one previous version of a class to walk
3666 // during class unloading, which is saved because old methods in the class
3667 // are still running. Otherwise the previous version list is cleaned up.
3668 bool InstanceKlass::_has_previous_versions = false;
3669
3670 // Returns true if there are previous versions of a class for class
3671 // unloading only. Also resets the flag to false. purge_previous_version
3672 // will set the flag to true if there are any left, i.e., if there's any
3673 // work to do for next time. This is to avoid the expensive code cache
3674 // walk in CLDG::clean_deallocate_lists().
3675 bool InstanceKlass::has_previous_versions_and_reset() {
3676 bool ret = _has_previous_versions;
3677 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3678 ret ? "true" : "false");
3679 _has_previous_versions = false;
3680 return ret;
3681 }
3682
3683 // Purge previous versions before adding new previous versions of the class and
3684 // during class unloading.
3685 void InstanceKlass::purge_previous_version_list() {
3686 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3687 assert(has_been_redefined(), "Should only be called for main class");
3688
3689 // Quick exit.
3690 if (previous_versions() == NULL) {
3691 return;
3692 }
3693
3694 // This klass has previous versions so see what we can cleanup
3695 // while it is safe to do so.
3696
3697 int deleted_count = 0; // leave debugging breadcrumbs
3698 int live_count = 0;
3699 ClassLoaderData* loader_data = class_loader_data();
3700 assert(loader_data != NULL, "should never be null");
3701
3702 ResourceMark rm;
3703 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3704
3705 // previous versions are linked together through the InstanceKlass
3706 InstanceKlass* pv_node = previous_versions();
3707 InstanceKlass* last = this;
3708 int version = 0;
3709
3710 // check the previous versions list
3711 for (; pv_node != NULL; ) {
3712
3713 ConstantPool* pvcp = pv_node->constants();
3714 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3715
3716 if (!pvcp->on_stack()) {
3717 // If the constant pool isn't on stack, none of the methods
3718 // are executing. Unlink this previous_version.
3719 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3720 // so will be deallocated during the next phase of class unloading.
3721 log_trace(redefine, class, iklass, purge)
3722 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3723 // For debugging purposes.
3724 pv_node->set_is_scratch_class();
3725 // Unlink from previous version list.
3726 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3727 InstanceKlass* next = pv_node->previous_versions();
3728 pv_node->link_previous_versions(NULL); // point next to NULL
3729 last->link_previous_versions(next);
3730 // Add to the deallocate list after unlinking
3731 loader_data->add_to_deallocate_list(pv_node);
3732 pv_node = next;
3733 deleted_count++;
3734 version++;
3735 continue;
3736 } else {
3737 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3738 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3739 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3740 live_count++;
3741 // found a previous version for next time we do class unloading
3742 _has_previous_versions = true;
3743 }
3744
3745 // At least one method is live in this previous version.
3746 // Reset dead EMCP methods not to get breakpoints.
3747 // All methods are deallocated when all of the methods for this class are no
3748 // longer running.
3749 Array<Method*>* method_refs = pv_node->methods();
3750 if (method_refs != NULL) {
3751 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3752 for (int j = 0; j < method_refs->length(); j++) {
3753 Method* method = method_refs->at(j);
3754
3755 if (!method->on_stack()) {
3756 // no breakpoints for non-running methods
3757 if (method->is_running_emcp()) {
3758 method->set_running_emcp(false);
3759 }
3760 } else {
3761 assert (method->is_obsolete() || method->is_running_emcp(),
3762 "emcp method cannot run after emcp bit is cleared");
3763 log_trace(redefine, class, iklass, purge)
3764 ("purge: %s(%s): prev method @%d in version @%d is alive",
3765 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3766 }
3767 }
3768 }
3769 // next previous version
3770 last = pv_node;
3771 pv_node = pv_node->previous_versions();
3772 version++;
3773 }
3774 log_trace(redefine, class, iklass, purge)
3775 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3776 }
3777
3778 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3779 int emcp_method_count) {
3780 int obsolete_method_count = old_methods->length() - emcp_method_count;
3781
3782 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3783 _previous_versions != NULL) {
3784 // We have a mix of obsolete and EMCP methods so we have to
3785 // clear out any matching EMCP method entries the hard way.
3786 int local_count = 0;
3787 for (int i = 0; i < old_methods->length(); i++) {
3788 Method* old_method = old_methods->at(i);
3789 if (old_method->is_obsolete()) {
3790 // only obsolete methods are interesting
3791 Symbol* m_name = old_method->name();
3792 Symbol* m_signature = old_method->signature();
3793
3794 // previous versions are linked together through the InstanceKlass
3795 int j = 0;
3796 for (InstanceKlass* prev_version = _previous_versions;
3797 prev_version != NULL;
3798 prev_version = prev_version->previous_versions(), j++) {
3799
3800 Array<Method*>* method_refs = prev_version->methods();
3801 for (int k = 0; k < method_refs->length(); k++) {
3802 Method* method = method_refs->at(k);
3803
3804 if (!method->is_obsolete() &&
3805 method->name() == m_name &&
3806 method->signature() == m_signature) {
3807 // The current RedefineClasses() call has made all EMCP
3808 // versions of this method obsolete so mark it as obsolete
3809 log_trace(redefine, class, iklass, add)
3810 ("%s(%s): flush obsolete method @%d in version @%d",
3811 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3812
3813 method->set_is_obsolete();
3814 break;
3815 }
3816 }
3817
3818 // The previous loop may not find a matching EMCP method, but
3819 // that doesn't mean that we can optimize and not go any
3820 // further back in the PreviousVersion generations. The EMCP
3821 // method for this generation could have already been made obsolete,
3822 // but there still may be an older EMCP method that has not
3823 // been made obsolete.
3824 }
3825
3826 if (++local_count >= obsolete_method_count) {
3827 // no more obsolete methods so bail out now
3828 break;
3829 }
3830 }
3831 }
3832 }
3833 }
3834
3835 // Save the scratch_class as the previous version if any of the methods are running.
3836 // The previous_versions are used to set breakpoints in EMCP methods and they are
3837 // also used to clean MethodData links to redefined methods that are no longer running.
3838 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3839 int emcp_method_count) {
3840 assert(Thread::current()->is_VM_thread(),
3841 "only VMThread can add previous versions");
3842
3843 ResourceMark rm;
3844 log_trace(redefine, class, iklass, add)
3845 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3846
3847 // Clean out old previous versions for this class
3848 purge_previous_version_list();
3849
3850 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3851 // a previous redefinition may be made obsolete by this redefinition.
3852 Array<Method*>* old_methods = scratch_class->methods();
3853 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3854
3855 // If the constant pool for this previous version of the class
3856 // is not marked as being on the stack, then none of the methods
3857 // in this previous version of the class are on the stack so
3858 // we don't need to add this as a previous version.
3859 ConstantPool* cp_ref = scratch_class->constants();
3860 if (!cp_ref->on_stack()) {
3861 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3862 // For debugging purposes.
3863 scratch_class->set_is_scratch_class();
3864 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3865 return;
3866 }
3867
3868 if (emcp_method_count != 0) {
3869 // At least one method is still running, check for EMCP methods
3870 for (int i = 0; i < old_methods->length(); i++) {
3871 Method* old_method = old_methods->at(i);
3872 if (!old_method->is_obsolete() && old_method->on_stack()) {
3873 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3874 // we can add breakpoints for it.
3875
3876 // We set the method->on_stack bit during safepoints for class redefinition
3877 // and use this bit to set the is_running_emcp bit.
3878 // After the safepoint, the on_stack bit is cleared and the running emcp
3879 // method may exit. If so, we would set a breakpoint in a method that
3880 // is never reached, but this won't be noticeable to the programmer.
3881 old_method->set_running_emcp(true);
3882 log_trace(redefine, class, iklass, add)
3883 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3884 } else if (!old_method->is_obsolete()) {
3885 log_trace(redefine, class, iklass, add)
3886 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3887 }
3888 }
3889 }
3890
3891 // Add previous version if any methods are still running.
3892 // Set has_previous_version flag for processing during class unloading.
3893 _has_previous_versions = true;
3894 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3895 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3896 scratch_class->link_previous_versions(previous_versions());
3897 link_previous_versions(scratch_class);
3898 } // end add_previous_version()
3899
3900 #endif // INCLUDE_JVMTI
3901
3902 Method* InstanceKlass::method_with_idnum(int idnum) {
3903 Method* m = NULL;
3904 if (idnum < methods()->length()) {
3905 m = methods()->at(idnum);
3906 }
3907 if (m == NULL || m->method_idnum() != idnum) {
3908 for (int index = 0; index < methods()->length(); ++index) {
3909 m = methods()->at(index);
3910 if (m->method_idnum() == idnum) {
3911 return m;
3912 }
3913 }
3914 // None found, return null for the caller to handle.
3915 return NULL;
3916 }
3917 return m;
3918 }
3919
3920
3921 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3922 if (idnum >= methods()->length()) {
3923 return NULL;
3924 }
3925 Method* m = methods()->at(idnum);
3926 if (m != NULL && m->orig_method_idnum() == idnum) {
3927 return m;
3928 }
3929 // Obsolete method idnum does not match the original idnum
3930 for (int index = 0; index < methods()->length(); ++index) {
3931 m = methods()->at(index);
3932 if (m->orig_method_idnum() == idnum) {
3933 return m;
3934 }
3935 }
3936 // None found, return null for the caller to handle.
3937 return NULL;
3938 }
3939
3940
3941 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3942 InstanceKlass* holder = get_klass_version(version);
3943 if (holder == NULL) {
3944 return NULL; // The version of klass is gone, no method is found
3945 }
3946 Method* method = holder->method_with_orig_idnum(idnum);
3947 return method;
3948 }
3949
3950 #if INCLUDE_JVMTI
3951 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3952 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3953 // Ignore the archived class stream data
3954 return NULL;
3955 } else {
3956 return _cached_class_file;
3957 }
3958 }
3959
3960 jint InstanceKlass::get_cached_class_file_len() {
3961 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3962 }
3963
3964 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3965 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3966 }
3967
3968 #if INCLUDE_CDS
3969 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3970 if (DumpSharedSpaces) {
3971 return _cached_class_file;
3972 } else {
3973 assert(this->is_shared(), "class should be shared");
3974 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3975 return _cached_class_file;
3976 } else {
3977 return NULL;
3978 }
3979 }
3980 }
3981 #endif
3982 #endif