1 /*
2 * Copyright (c) 1997, 2019, 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
is_class_loader(const Symbol * class_name,const ClassFileParser & parser)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
has_nest_member(InstanceKlass * k,TRAPS) const152 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 (though that should be impossible). But to be safe we
186 // have to check for a compiler thread executing here.
187 if (!THREAD->can_call_java() && !_constants->tag_at(cp_index).is_klass()) {
188 log_trace(class, nestmates)("- validation required resolution in an unsuitable thread");
189 return false;
190 }
191
192 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
193 if (k2 == k) {
194 log_trace(class, nestmates)("- class is listed as a nest member");
195 return true;
196 }
197 else {
198 // same name but different klass!
199 log_trace(class, nestmates)(" - klass comparison failed!");
200 // can't have two names the same, so we're done
201 return false;
202 }
203 }
204 }
205 }
206 log_trace(class, nestmates)("- class is NOT a nest member!");
207 return false;
208 }
209
210 // Return nest-host class, resolving, validating and saving it if needed.
211 // In cases where this is called from a thread that can not do classloading
212 // (such as a native JIT thread) then we simply return NULL, which in turn
213 // causes the access check to return false. Such code will retry the access
214 // from a more suitable environment later.
nest_host(Symbol * validationException,TRAPS)215 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
216 InstanceKlass* nest_host_k = _nest_host;
217 if (nest_host_k == NULL) {
218 // need to resolve and save our nest-host class. This could be attempted
219 // concurrently but as the result is idempotent and we don't use the class
220 // then we do not need any synchronization beyond what is implicitly used
221 // during class loading.
222 if (_nest_host_index != 0) { // we have a real nest_host
223 // Before trying to resolve check if we're in a suitable context
224 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
225 if (log_is_enabled(Trace, class, nestmates)) {
226 ResourceMark rm(THREAD);
227 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
228 this->external_name());
229 }
230 return NULL;
231 }
232
233 if (log_is_enabled(Trace, class, nestmates)) {
234 ResourceMark rm(THREAD);
235 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
236 this->external_name(),
237 _constants->klass_name_at(_nest_host_index)->as_C_string());
238 }
239
240 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
241 if (HAS_PENDING_EXCEPTION) {
242 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
243 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
244 // throw a new CDNFE with the original as its cause, and a clear msg
245 ResourceMark rm(THREAD);
246 char buf[200];
247 CLEAR_PENDING_EXCEPTION;
248 jio_snprintf(buf, sizeof(buf),
249 "Unable to load nest-host class (%s) of %s",
250 _constants->klass_name_at(_nest_host_index)->as_C_string(),
251 this->external_name());
252 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
253 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
254 }
255 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
256 return NULL;
257 }
258
259 // A valid nest-host is an instance class in the current package that lists this
260 // class as a nest member. If any of these conditions are not met we post the
261 // requested exception type (if any) and return NULL
262
263 const char* error = NULL;
264
265 // JVMS 5.4.4 indicates package check comes first
266 if (is_same_class_package(k)) {
267
268 // Now check actual membership. We can't be a member if our "host" is
269 // not an instance class.
270 if (k->is_instance_klass()) {
271 nest_host_k = InstanceKlass::cast(k);
272
273 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
274 if (is_member) {
275 // save resolved nest-host value
276 _nest_host = nest_host_k;
277
278 if (log_is_enabled(Trace, class, nestmates)) {
279 ResourceMark rm(THREAD);
280 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
281 this->external_name(), k->external_name());
282 }
283 return nest_host_k;
284 }
285 }
286 error = "current type is not listed as a nest member";
287 } else {
288 error = "types are in different packages";
289 }
290
291 if (log_is_enabled(Trace, class, nestmates)) {
292 ResourceMark rm(THREAD);
293 log_trace(class, nestmates)
294 ("Type %s (loader: %s) is not a nest member of "
295 "resolved type %s (loader: %s): %s",
296 this->external_name(),
297 this->class_loader_data()->loader_name_and_id(),
298 k->external_name(),
299 k->class_loader_data()->loader_name_and_id(),
300 error);
301 }
302
303 if (validationException != NULL && THREAD->can_call_java()) {
304 ResourceMark rm(THREAD);
305 Exceptions::fthrow(THREAD_AND_LOCATION,
306 validationException,
307 "Type %s (loader: %s) is not a nest member of %s (loader: %s): %s",
308 this->external_name(),
309 this->class_loader_data()->loader_name_and_id(),
310 k->external_name(),
311 k->class_loader_data()->loader_name_and_id(),
312 error
313 );
314 }
315 return NULL;
316 } else {
317 if (log_is_enabled(Trace, class, nestmates)) {
318 ResourceMark rm(THREAD);
319 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
320 this->external_name());
321 }
322 // save resolved nest-host value
323 return (_nest_host = this);
324 }
325 }
326 return nest_host_k;
327 }
328
329 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
330 // or we are k's nest_host - all of which is covered by comparing the two
331 // resolved_nest_hosts
has_nestmate_access_to(InstanceKlass * k,TRAPS)332 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
333
334 assert(this != k, "this should be handled by higher-level code");
335
336 // Per JVMS 5.4.4 we first resolve and validate the current class, then
337 // the target class k. Resolution exceptions will be passed on by upper
338 // layers. IncompatibleClassChangeErrors from membership validation failures
339 // will also be passed through.
340
341 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
342 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
343 if (cur_host == NULL) {
344 return false;
345 }
346
347 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
348 if (k_nest_host == NULL) {
349 return false;
350 }
351
352 bool access = (cur_host == k_nest_host);
353
354 if (log_is_enabled(Trace, class, nestmates)) {
355 ResourceMark rm(THREAD);
356 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
357 this->external_name(),
358 access ? "" : "NOT ",
359 k->external_name());
360 }
361
362 return access;
363 }
364
allocate_instance_klass(const ClassFileParser & parser,TRAPS)365 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
366 const int size = InstanceKlass::size(parser.vtable_size(),
367 parser.itable_size(),
368 nonstatic_oop_map_size(parser.total_oop_map_count()),
369 parser.is_interface(),
370 parser.is_unsafe_anonymous(),
371 should_store_fingerprint(parser.is_unsafe_anonymous()));
372
373 const Symbol* const class_name = parser.class_name();
374 assert(class_name != NULL, "invariant");
375 ClassLoaderData* loader_data = parser.loader_data();
376 assert(loader_data != NULL, "invariant");
377
378 InstanceKlass* ik;
379
380 // Allocation
381 if (REF_NONE == parser.reference_type()) {
382 if (class_name == vmSymbols::java_lang_Class()) {
383 // mirror
384 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
385 }
386 else if (is_class_loader(class_name, parser)) {
387 // class loader
388 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
389 } else {
390 // normal
391 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
392 }
393 } else {
394 // reference
395 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
396 }
397
398 // Check for pending exception before adding to the loader data and incrementing
399 // class count. Can get OOM here.
400 if (HAS_PENDING_EXCEPTION) {
401 return NULL;
402 }
403
404 return ik;
405 }
406
407
408 // copy method ordering from resource area to Metaspace
copy_method_ordering(const intArray * m,TRAPS)409 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
410 if (m != NULL) {
411 // allocate a new array and copy contents (memcpy?)
412 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
413 for (int i = 0; i < m->length(); i++) {
414 _method_ordering->at_put(i, m->at(i));
415 }
416 } else {
417 _method_ordering = Universe::the_empty_int_array();
418 }
419 }
420
421 // create a new array of vtable_indices for default methods
create_new_default_vtable_indices(int len,TRAPS)422 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
423 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
424 assert(default_vtable_indices() == NULL, "only create once");
425 set_default_vtable_indices(vtable_indices);
426 return vtable_indices;
427 }
428
InstanceKlass(const ClassFileParser & parser,unsigned kind,KlassID id)429 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
430 Klass(id),
431 _nest_members(NULL),
432 _nest_host_index(0),
433 _nest_host(NULL),
434 _static_field_size(parser.static_field_size()),
435 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
436 _itable_len(parser.itable_size()),
437 _reference_type(parser.reference_type())
438 {
439 set_vtable_length(parser.vtable_size());
440 set_kind(kind);
441 set_access_flags(parser.access_flags());
442 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
443 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
444 false));
445
446 assert(NULL == _methods, "underlying memory not zeroed?");
447 assert(is_instance_klass(), "is layout incorrect?");
448 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
449
450 if (DumpSharedSpaces) {
451 SystemDictionaryShared::init_dumptime_info(this);
452 }
453 }
454
deallocate_methods(ClassLoaderData * loader_data,Array<Method * > * methods)455 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
456 Array<Method*>* methods) {
457 if (methods != NULL && methods != Universe::the_empty_method_array() &&
458 !methods->is_shared()) {
459 for (int i = 0; i < methods->length(); i++) {
460 Method* method = methods->at(i);
461 if (method == NULL) continue; // maybe null if error processing
462 // Only want to delete methods that are not executing for RedefineClasses.
463 // The previous version will point to them so they're not totally dangling
464 assert (!method->on_stack(), "shouldn't be called with methods on stack");
465 MetadataFactory::free_metadata(loader_data, method);
466 }
467 MetadataFactory::free_array<Method*>(loader_data, methods);
468 }
469 }
470
deallocate_interfaces(ClassLoaderData * loader_data,const Klass * super_klass,Array<InstanceKlass * > * local_interfaces,Array<InstanceKlass * > * transitive_interfaces)471 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
472 const Klass* super_klass,
473 Array<InstanceKlass*>* local_interfaces,
474 Array<InstanceKlass*>* transitive_interfaces) {
475 // Only deallocate transitive interfaces if not empty, same as super class
476 // or same as local interfaces. See code in parseClassFile.
477 Array<InstanceKlass*>* ti = transitive_interfaces;
478 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
479 // check that the interfaces don't come from super class
480 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
481 InstanceKlass::cast(super_klass)->transitive_interfaces();
482 if (ti != sti && ti != NULL && !ti->is_shared()) {
483 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
484 }
485 }
486
487 // local interfaces can be empty
488 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
489 local_interfaces != NULL && !local_interfaces->is_shared()) {
490 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
491 }
492 }
493
494 // This function deallocates the metadata and C heap pointers that the
495 // InstanceKlass points to.
deallocate_contents(ClassLoaderData * loader_data)496 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
497
498 // Orphan the mirror first, CMS thinks it's still live.
499 if (java_mirror() != NULL) {
500 java_lang_Class::set_klass(java_mirror(), NULL);
501 }
502
503 // Also remove mirror from handles
504 loader_data->remove_handle(_java_mirror);
505
506 // Need to take this class off the class loader data list.
507 loader_data->remove_class(this);
508
509 // The array_klass for this class is created later, after error handling.
510 // For class redefinition, we keep the original class so this scratch class
511 // doesn't have an array class. Either way, assert that there is nothing
512 // to deallocate.
513 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
514
515 // Release C heap allocated data that this might point to, which includes
516 // reference counting symbol names.
517 release_C_heap_structures();
518
519 deallocate_methods(loader_data, methods());
520 set_methods(NULL);
521
522 if (method_ordering() != NULL &&
523 method_ordering() != Universe::the_empty_int_array() &&
524 !method_ordering()->is_shared()) {
525 MetadataFactory::free_array<int>(loader_data, method_ordering());
526 }
527 set_method_ordering(NULL);
528
529 // default methods can be empty
530 if (default_methods() != NULL &&
531 default_methods() != Universe::the_empty_method_array() &&
532 !default_methods()->is_shared()) {
533 MetadataFactory::free_array<Method*>(loader_data, default_methods());
534 }
535 // Do NOT deallocate the default methods, they are owned by superinterfaces.
536 set_default_methods(NULL);
537
538 // default methods vtable indices can be empty
539 if (default_vtable_indices() != NULL &&
540 !default_vtable_indices()->is_shared()) {
541 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
542 }
543 set_default_vtable_indices(NULL);
544
545
546 // This array is in Klass, but remove it with the InstanceKlass since
547 // this place would be the only caller and it can share memory with transitive
548 // interfaces.
549 if (secondary_supers() != NULL &&
550 secondary_supers() != Universe::the_empty_klass_array() &&
551 // see comments in compute_secondary_supers about the following cast
552 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
553 !secondary_supers()->is_shared()) {
554 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
555 }
556 set_secondary_supers(NULL);
557
558 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
559 set_transitive_interfaces(NULL);
560 set_local_interfaces(NULL);
561
562 if (fields() != NULL && !fields()->is_shared()) {
563 MetadataFactory::free_array<jushort>(loader_data, fields());
564 }
565 set_fields(NULL, 0);
566
567 // If a method from a redefined class is using this constant pool, don't
568 // delete it, yet. The new class's previous version will point to this.
569 if (constants() != NULL) {
570 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
571 if (!constants()->is_shared()) {
572 MetadataFactory::free_metadata(loader_data, constants());
573 }
574 // Delete any cached resolution errors for the constant pool
575 SystemDictionary::delete_resolution_error(constants());
576
577 set_constants(NULL);
578 }
579
580 if (inner_classes() != NULL &&
581 inner_classes() != Universe::the_empty_short_array() &&
582 !inner_classes()->is_shared()) {
583 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
584 }
585 set_inner_classes(NULL);
586
587 if (nest_members() != NULL &&
588 nest_members() != Universe::the_empty_short_array() &&
589 !nest_members()->is_shared()) {
590 MetadataFactory::free_array<jushort>(loader_data, nest_members());
591 }
592 set_nest_members(NULL);
593
594 // We should deallocate the Annotations instance if it's not in shared spaces.
595 if (annotations() != NULL && !annotations()->is_shared()) {
596 MetadataFactory::free_metadata(loader_data, annotations());
597 }
598 set_annotations(NULL);
599
600 if (DumpSharedSpaces) {
601 SystemDictionaryShared::remove_dumptime_info(this);
602 }
603 }
604
should_be_initialized() const605 bool InstanceKlass::should_be_initialized() const {
606 return !is_initialized();
607 }
608
itable() const609 klassItable InstanceKlass::itable() const {
610 return klassItable(const_cast<InstanceKlass*>(this));
611 }
612
eager_initialize(Thread * thread)613 void InstanceKlass::eager_initialize(Thread *thread) {
614 if (!EagerInitialization) return;
615
616 if (this->is_not_initialized()) {
617 // abort if the the class has a class initializer
618 if (this->class_initializer() != NULL) return;
619
620 // abort if it is java.lang.Object (initialization is handled in genesis)
621 Klass* super_klass = super();
622 if (super_klass == NULL) return;
623
624 // abort if the super class should be initialized
625 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
626
627 // call body to expose the this pointer
628 eager_initialize_impl();
629 }
630 }
631
632 // JVMTI spec thinks there are signers and protection domain in the
633 // instanceKlass. These accessors pretend these fields are there.
634 // The hprof specification also thinks these fields are in InstanceKlass.
protection_domain() const635 oop InstanceKlass::protection_domain() const {
636 // return the protection_domain from the mirror
637 return java_lang_Class::protection_domain(java_mirror());
638 }
639
640 // To remove these from requires an incompatible change and CCC request.
signers() const641 objArrayOop InstanceKlass::signers() const {
642 // return the signers from the mirror
643 return java_lang_Class::signers(java_mirror());
644 }
645
init_lock() const646 oop InstanceKlass::init_lock() const {
647 // return the init lock from the mirror
648 oop lock = java_lang_Class::init_lock(java_mirror());
649 // Prevent reordering with any access of initialization state
650 OrderAccess::loadload();
651 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
652 "only fully initialized state can have a null lock");
653 return lock;
654 }
655
656 // Set the initialization lock to null so the object can be GC'ed. Any racing
657 // threads to get this lock will see a null lock and will not lock.
658 // That's okay because they all check for initialized state after getting
659 // the lock and return.
fence_and_clear_init_lock()660 void InstanceKlass::fence_and_clear_init_lock() {
661 // make sure previous stores are all done, notably the init_state.
662 OrderAccess::storestore();
663 java_lang_Class::set_init_lock(java_mirror(), NULL);
664 assert(!is_not_initialized(), "class must be initialized now");
665 }
666
eager_initialize_impl()667 void InstanceKlass::eager_initialize_impl() {
668 EXCEPTION_MARK;
669 HandleMark hm(THREAD);
670 Handle h_init_lock(THREAD, init_lock());
671 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
672
673 // abort if someone beat us to the initialization
674 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
675
676 ClassState old_state = init_state();
677 link_class_impl(THREAD);
678 if (HAS_PENDING_EXCEPTION) {
679 CLEAR_PENDING_EXCEPTION;
680 // Abort if linking the class throws an exception.
681
682 // Use a test to avoid redundantly resetting the state if there's
683 // no change. Set_init_state() asserts that state changes make
684 // progress, whereas here we might just be spinning in place.
685 if (old_state != _init_state)
686 set_init_state(old_state);
687 } else {
688 // linking successfull, mark class as initialized
689 set_init_state(fully_initialized);
690 fence_and_clear_init_lock();
691 // trace
692 if (log_is_enabled(Info, class, init)) {
693 ResourceMark rm(THREAD);
694 log_info(class, init)("[Initialized %s without side effects]", external_name());
695 }
696 }
697 }
698
699
700 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
701 // process. The step comments refers to the procedure described in that section.
702 // Note: implementation moved to static method to expose the this pointer.
initialize(TRAPS)703 void InstanceKlass::initialize(TRAPS) {
704 if (this->should_be_initialized()) {
705 initialize_impl(CHECK);
706 // Note: at this point the class may be initialized
707 // OR it may be in the state of being initialized
708 // in case of recursive initialization!
709 } else {
710 assert(is_initialized(), "sanity check");
711 }
712 }
713
714
verify_code(TRAPS)715 bool InstanceKlass::verify_code(TRAPS) {
716 // 1) Verify the bytecodes
717 return Verifier::verify(this, should_verify_class(), THREAD);
718 }
719
link_class(TRAPS)720 void InstanceKlass::link_class(TRAPS) {
721 assert(is_loaded(), "must be loaded");
722 if (!is_linked()) {
723 link_class_impl(CHECK);
724 }
725 }
726
727 // Called to verify that a class can link during initialization, without
728 // throwing a VerifyError.
link_class_or_fail(TRAPS)729 bool InstanceKlass::link_class_or_fail(TRAPS) {
730 assert(is_loaded(), "must be loaded");
731 if (!is_linked()) {
732 link_class_impl(CHECK_false);
733 }
734 return is_linked();
735 }
736
link_class_impl(TRAPS)737 bool InstanceKlass::link_class_impl(TRAPS) {
738 if (DumpSharedSpaces && is_in_error_state()) {
739 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
740 // the class has failed verification. Throwing the NoClassDefFoundError here is just
741 // a convenient way to stop repeat attempts to verify the same (bad) class.
742 //
743 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
744 // if we are executing Java code. This is not a problem for CDS dumping phase since
745 // it doesn't execute any Java code.
746 ResourceMark rm(THREAD);
747 Exceptions::fthrow(THREAD_AND_LOCATION,
748 vmSymbols::java_lang_NoClassDefFoundError(),
749 "Class %s, or one of its supertypes, failed class initialization",
750 external_name());
751 return false;
752 }
753 // return if already verified
754 if (is_linked()) {
755 return true;
756 }
757
758 // Timing
759 // timer handles recursion
760 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
761 JavaThread* jt = (JavaThread*)THREAD;
762
763 // link super class before linking this class
764 Klass* super_klass = super();
765 if (super_klass != NULL) {
766 if (super_klass->is_interface()) { // check if super class is an interface
767 ResourceMark rm(THREAD);
768 Exceptions::fthrow(
769 THREAD_AND_LOCATION,
770 vmSymbols::java_lang_IncompatibleClassChangeError(),
771 "class %s has interface %s as super class",
772 external_name(),
773 super_klass->external_name()
774 );
775 return false;
776 }
777
778 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
779 ik_super->link_class_impl(CHECK_false);
780 }
781
782 // link all interfaces implemented by this class before linking this class
783 Array<InstanceKlass*>* interfaces = local_interfaces();
784 int num_interfaces = interfaces->length();
785 for (int index = 0; index < num_interfaces; index++) {
786 InstanceKlass* interk = interfaces->at(index);
787 interk->link_class_impl(CHECK_false);
788 }
789
790 // in case the class is linked in the process of linking its superclasses
791 if (is_linked()) {
792 return true;
793 }
794
795 // trace only the link time for this klass that includes
796 // the verification time
797 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
798 ClassLoader::perf_class_link_selftime(),
799 ClassLoader::perf_classes_linked(),
800 jt->get_thread_stat()->perf_recursion_counts_addr(),
801 jt->get_thread_stat()->perf_timers_addr(),
802 PerfClassTraceTime::CLASS_LINK);
803
804 // verification & rewriting
805 {
806 HandleMark hm(THREAD);
807 Handle h_init_lock(THREAD, init_lock());
808 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
809 // rewritten will have been set if loader constraint error found
810 // on an earlier link attempt
811 // don't verify or rewrite if already rewritten
812 //
813
814 if (!is_linked()) {
815 if (!is_rewritten()) {
816 {
817 bool verify_ok = verify_code(THREAD);
818 if (!verify_ok) {
819 return false;
820 }
821 }
822
823 // Just in case a side-effect of verify linked this class already
824 // (which can sometimes happen since the verifier loads classes
825 // using custom class loaders, which are free to initialize things)
826 if (is_linked()) {
827 return true;
828 }
829
830 // also sets rewritten
831 rewrite_class(CHECK_false);
832 } else if (is_shared()) {
833 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
834 }
835
836 // relocate jsrs and link methods after they are all rewritten
837 link_methods(CHECK_false);
838
839 // Initialize the vtable and interface table after
840 // methods have been rewritten since rewrite may
841 // fabricate new Method*s.
842 // also does loader constraint checking
843 //
844 // initialize_vtable and initialize_itable need to be rerun for
845 // a shared class if the class is not loaded by the NULL classloader.
846 ClassLoaderData * loader_data = class_loader_data();
847 if (!(is_shared() &&
848 loader_data->is_the_null_class_loader_data())) {
849 vtable().initialize_vtable(true, CHECK_false);
850 itable().initialize_itable(true, CHECK_false);
851 }
852 #ifdef ASSERT
853 else {
854 vtable().verify(tty, true);
855 // In case itable verification is ever added.
856 // itable().verify(tty, true);
857 }
858 #endif
859 set_init_state(linked);
860 if (JvmtiExport::should_post_class_prepare()) {
861 Thread *thread = THREAD;
862 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
863 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
864 }
865 }
866 }
867 return true;
868 }
869
870 // Rewrite the byte codes of all of the methods of a class.
871 // The rewriter must be called exactly once. Rewriting must happen after
872 // verification but before the first method of the class is executed.
rewrite_class(TRAPS)873 void InstanceKlass::rewrite_class(TRAPS) {
874 assert(is_loaded(), "must be loaded");
875 if (is_rewritten()) {
876 assert(is_shared(), "rewriting an unshared class?");
877 return;
878 }
879 Rewriter::rewrite(this, CHECK);
880 set_rewritten();
881 }
882
883 // Now relocate and link method entry points after class is rewritten.
884 // This is outside is_rewritten flag. In case of an exception, it can be
885 // executed more than once.
link_methods(TRAPS)886 void InstanceKlass::link_methods(TRAPS) {
887 int len = methods()->length();
888 for (int i = len-1; i >= 0; i--) {
889 methodHandle m(THREAD, methods()->at(i));
890
891 // Set up method entry points for compiler and interpreter .
892 m->link_method(m, CHECK);
893 }
894 }
895
896 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
initialize_super_interfaces(TRAPS)897 void InstanceKlass::initialize_super_interfaces(TRAPS) {
898 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
899 for (int i = 0; i < local_interfaces()->length(); ++i) {
900 InstanceKlass* ik = local_interfaces()->at(i);
901
902 // Initialization is depth first search ie. we start with top of the inheritance tree
903 // has_nonstatic_concrete_methods drives searching superinterfaces since it
904 // means has_nonstatic_concrete_methods in its superinterface hierarchy
905 if (ik->has_nonstatic_concrete_methods()) {
906 ik->initialize_super_interfaces(CHECK);
907 }
908
909 // Only initialize() interfaces that "declare" concrete methods.
910 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
911 ik->initialize(CHECK);
912 }
913 }
914 }
915
initialize_impl(TRAPS)916 void InstanceKlass::initialize_impl(TRAPS) {
917 HandleMark hm(THREAD);
918
919 // Make sure klass is linked (verified) before initialization
920 // A class could already be verified, since it has been reflected upon.
921 link_class(CHECK);
922
923 DTRACE_CLASSINIT_PROBE(required, -1);
924
925 bool wait = false;
926
927 // refer to the JVM book page 47 for description of steps
928 // Step 1
929 {
930 Handle h_init_lock(THREAD, init_lock());
931 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
932
933 Thread *self = THREAD; // it's passed the current thread
934
935 // Step 2
936 // If we were to use wait() instead of waitInterruptibly() then
937 // we might end up throwing IE from link/symbol resolution sites
938 // that aren't expected to throw. This would wreak havoc. See 6320309.
939 while(is_being_initialized() && !is_reentrant_initialization(self)) {
940 wait = true;
941 ol.waitUninterruptibly(CHECK);
942 }
943
944 // Step 3
945 if (is_being_initialized() && is_reentrant_initialization(self)) {
946 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
947 return;
948 }
949
950 // Step 4
951 if (is_initialized()) {
952 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
953 return;
954 }
955
956 // Step 5
957 if (is_in_error_state()) {
958 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
959 ResourceMark rm(THREAD);
960 const char* desc = "Could not initialize class ";
961 const char* className = external_name();
962 size_t msglen = strlen(desc) + strlen(className) + 1;
963 char* message = NEW_RESOURCE_ARRAY(char, msglen);
964 if (NULL == message) {
965 // Out of memory: can't create detailed error message
966 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
967 } else {
968 jio_snprintf(message, msglen, "%s%s", desc, className);
969 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
970 }
971 }
972
973 // Step 6
974 set_init_state(being_initialized);
975 set_init_thread(self);
976 }
977
978 // Step 7
979 // Next, if C is a class rather than an interface, initialize it's super class and super
980 // interfaces.
981 if (!is_interface()) {
982 Klass* super_klass = super();
983 if (super_klass != NULL && super_klass->should_be_initialized()) {
984 super_klass->initialize(THREAD);
985 }
986 // If C implements any interface that declares a non-static, concrete method,
987 // the initialization of C triggers initialization of its super interfaces.
988 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
989 // having a superinterface that declares, non-static, concrete methods
990 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
991 initialize_super_interfaces(THREAD);
992 }
993
994 // If any exceptions, complete abruptly, throwing the same exception as above.
995 if (HAS_PENDING_EXCEPTION) {
996 Handle e(THREAD, PENDING_EXCEPTION);
997 CLEAR_PENDING_EXCEPTION;
998 {
999 EXCEPTION_MARK;
1000 // Locks object, set state, and notify all waiting threads
1001 set_initialization_state_and_notify(initialization_error, THREAD);
1002 CLEAR_PENDING_EXCEPTION;
1003 }
1004 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1005 THROW_OOP(e());
1006 }
1007 }
1008
1009
1010 // Look for aot compiled methods for this klass, including class initializer.
1011 AOTLoader::load_for_klass(this, THREAD);
1012
1013 // Step 8
1014 {
1015 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
1016 JavaThread* jt = (JavaThread*)THREAD;
1017 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1018 // Timer includes any side effects of class initialization (resolution,
1019 // etc), but not recursive entry into call_class_initializer().
1020 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1021 ClassLoader::perf_class_init_selftime(),
1022 ClassLoader::perf_classes_inited(),
1023 jt->get_thread_stat()->perf_recursion_counts_addr(),
1024 jt->get_thread_stat()->perf_timers_addr(),
1025 PerfClassTraceTime::CLASS_CLINIT);
1026 call_class_initializer(THREAD);
1027 }
1028
1029 // Step 9
1030 if (!HAS_PENDING_EXCEPTION) {
1031 set_initialization_state_and_notify(fully_initialized, CHECK);
1032 {
1033 debug_only(vtable().verify(tty, true);)
1034 }
1035 }
1036 else {
1037 // Step 10 and 11
1038 Handle e(THREAD, PENDING_EXCEPTION);
1039 CLEAR_PENDING_EXCEPTION;
1040 // JVMTI has already reported the pending exception
1041 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1042 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1043 {
1044 EXCEPTION_MARK;
1045 set_initialization_state_and_notify(initialization_error, THREAD);
1046 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1047 // JVMTI has already reported the pending exception
1048 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1049 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1050 }
1051 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1052 if (e->is_a(SystemDictionary::Error_klass())) {
1053 THROW_OOP(e());
1054 } else {
1055 JavaCallArguments args(e);
1056 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1057 vmSymbols::throwable_void_signature(),
1058 &args);
1059 }
1060 }
1061 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1062 }
1063
1064
set_initialization_state_and_notify(ClassState state,TRAPS)1065 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1066 Handle h_init_lock(THREAD, init_lock());
1067 if (h_init_lock() != NULL) {
1068 ObjectLocker ol(h_init_lock, THREAD);
1069 set_init_state(state);
1070 fence_and_clear_init_lock();
1071 ol.notify_all(CHECK);
1072 } else {
1073 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1074 set_init_state(state);
1075 }
1076 }
1077
implementor() const1078 Klass* InstanceKlass::implementor() const {
1079 Klass* volatile* k = adr_implementor();
1080 if (k == NULL) {
1081 return NULL;
1082 } else {
1083 // This load races with inserts, and therefore needs acquire.
1084 Klass* kls = OrderAccess::load_acquire(k);
1085 if (kls != NULL && !kls->is_loader_alive()) {
1086 return NULL; // don't return unloaded class
1087 } else {
1088 return kls;
1089 }
1090 }
1091 }
1092
1093
set_implementor(Klass * k)1094 void InstanceKlass::set_implementor(Klass* k) {
1095 assert_lock_strong(Compile_lock);
1096 assert(is_interface(), "not interface");
1097 Klass* volatile* addr = adr_implementor();
1098 assert(addr != NULL, "null addr");
1099 if (addr != NULL) {
1100 OrderAccess::release_store(addr, k);
1101 }
1102 }
1103
nof_implementors() const1104 int InstanceKlass::nof_implementors() const {
1105 Klass* k = implementor();
1106 if (k == NULL) {
1107 return 0;
1108 } else if (k != this) {
1109 return 1;
1110 } else {
1111 return 2;
1112 }
1113 }
1114
1115 // The embedded _implementor field can only record one implementor.
1116 // When there are more than one implementors, the _implementor field
1117 // is set to the interface Klass* itself. Following are the possible
1118 // values for the _implementor field:
1119 // NULL - no implementor
1120 // implementor Klass* - one implementor
1121 // self - more than one implementor
1122 //
1123 // The _implementor field only exists for interfaces.
add_implementor(Klass * k)1124 void InstanceKlass::add_implementor(Klass* k) {
1125 assert_lock_strong(Compile_lock);
1126 assert(is_interface(), "not interface");
1127 // Filter out my subinterfaces.
1128 // (Note: Interfaces are never on the subklass list.)
1129 if (InstanceKlass::cast(k)->is_interface()) return;
1130
1131 // Filter out subclasses whose supers already implement me.
1132 // (Note: CHA must walk subclasses of direct implementors
1133 // in order to locate indirect implementors.)
1134 Klass* sk = k->super();
1135 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1136 // We only need to check one immediate superclass, since the
1137 // implements_interface query looks at transitive_interfaces.
1138 // Any supers of the super have the same (or fewer) transitive_interfaces.
1139 return;
1140
1141 Klass* ik = implementor();
1142 if (ik == NULL) {
1143 set_implementor(k);
1144 } else if (ik != this) {
1145 // There is already an implementor. Use itself as an indicator of
1146 // more than one implementors.
1147 set_implementor(this);
1148 }
1149
1150 // The implementor also implements the transitive_interfaces
1151 for (int index = 0; index < local_interfaces()->length(); index++) {
1152 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1153 }
1154 }
1155
init_implementor()1156 void InstanceKlass::init_implementor() {
1157 if (is_interface()) {
1158 set_implementor(NULL);
1159 }
1160 }
1161
1162
process_interfaces(Thread * thread)1163 void InstanceKlass::process_interfaces(Thread *thread) {
1164 // link this class into the implementors list of every interface it implements
1165 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1166 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1167 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1168 assert(interf->is_interface(), "expected interface");
1169 interf->add_implementor(this);
1170 }
1171 }
1172
can_be_primary_super_slow() const1173 bool InstanceKlass::can_be_primary_super_slow() const {
1174 if (is_interface())
1175 return false;
1176 else
1177 return Klass::can_be_primary_super_slow();
1178 }
1179
compute_secondary_supers(int num_extra_slots,Array<InstanceKlass * > * transitive_interfaces)1180 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1181 Array<InstanceKlass*>* transitive_interfaces) {
1182 // The secondaries are the implemented interfaces.
1183 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1184 int num_secondaries = num_extra_slots + interfaces->length();
1185 if (num_secondaries == 0) {
1186 // Must share this for correct bootstrapping!
1187 set_secondary_supers(Universe::the_empty_klass_array());
1188 return NULL;
1189 } else if (num_extra_slots == 0) {
1190 // The secondary super list is exactly the same as the transitive interfaces, so
1191 // let's use it instead of making a copy.
1192 // Redefine classes has to be careful not to delete this!
1193 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1194 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1195 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1196 return NULL;
1197 } else {
1198 // Copy transitive interfaces to a temporary growable array to be constructed
1199 // into the secondary super list with extra slots.
1200 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1201 for (int i = 0; i < interfaces->length(); i++) {
1202 secondaries->push(interfaces->at(i));
1203 }
1204 return secondaries;
1205 }
1206 }
1207
compute_is_subtype_of(Klass * k)1208 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1209 if (k->is_interface()) {
1210 return implements_interface(k);
1211 } else {
1212 return Klass::compute_is_subtype_of(k);
1213 }
1214 }
1215
implements_interface(Klass * k) const1216 bool InstanceKlass::implements_interface(Klass* k) const {
1217 if (this == k) return true;
1218 assert(k->is_interface(), "should be an interface class");
1219 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1220 if (transitive_interfaces()->at(i) == k) {
1221 return true;
1222 }
1223 }
1224 return false;
1225 }
1226
is_same_or_direct_interface(Klass * k) const1227 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1228 // Verify direct super interface
1229 if (this == k) return true;
1230 assert(k->is_interface(), "should be an interface class");
1231 for (int i = 0; i < local_interfaces()->length(); i++) {
1232 if (local_interfaces()->at(i) == k) {
1233 return true;
1234 }
1235 }
1236 return false;
1237 }
1238
allocate_objArray(int n,int length,TRAPS)1239 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1240 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1241 int size = objArrayOopDesc::object_size(length);
1242 Klass* ak = array_klass(n, CHECK_NULL);
1243 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1244 /* do_zero */ true, CHECK_NULL);
1245 return o;
1246 }
1247
register_finalizer(instanceOop i,TRAPS)1248 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1249 if (TraceFinalizerRegistration) {
1250 tty->print("Registered ");
1251 i->print_value_on(tty);
1252 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1253 }
1254 instanceHandle h_i(THREAD, i);
1255 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1256 JavaValue result(T_VOID);
1257 JavaCallArguments args(h_i);
1258 methodHandle mh (THREAD, Universe::finalizer_register_method());
1259 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1260 return h_i();
1261 }
1262
allocate_instance(TRAPS)1263 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1264 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1265 int size = size_helper(); // Query before forming handle.
1266
1267 instanceOop i;
1268
1269 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1270 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1271 i = register_finalizer(i, CHECK_NULL);
1272 }
1273 return i;
1274 }
1275
allocate_instance_handle(TRAPS)1276 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1277 return instanceHandle(THREAD, allocate_instance(THREAD));
1278 }
1279
check_valid_for_instantiation(bool throwError,TRAPS)1280 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1281 if (is_interface() || is_abstract()) {
1282 ResourceMark rm(THREAD);
1283 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1284 : vmSymbols::java_lang_InstantiationException(), external_name());
1285 }
1286 if (this == SystemDictionary::Class_klass()) {
1287 ResourceMark rm(THREAD);
1288 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1289 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1290 }
1291 }
1292
array_klass_impl(bool or_null,int n,TRAPS)1293 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1294 // Need load-acquire for lock-free read
1295 if (array_klasses_acquire() == NULL) {
1296 if (or_null) return NULL;
1297
1298 ResourceMark rm;
1299 JavaThread *jt = (JavaThread *)THREAD;
1300 {
1301 // Atomic creation of array_klasses
1302 MutexLocker ma(MultiArray_lock, THREAD);
1303
1304 // Check if update has already taken place
1305 if (array_klasses() == NULL) {
1306 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1307 // use 'release' to pair with lock-free load
1308 release_set_array_klasses(k);
1309 }
1310 }
1311 }
1312 // _this will always be set at this point
1313 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1314 if (or_null) {
1315 return oak->array_klass_or_null(n);
1316 }
1317 return oak->array_klass(n, THREAD);
1318 }
1319
array_klass_impl(bool or_null,TRAPS)1320 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1321 return array_klass_impl(or_null, 1, THREAD);
1322 }
1323
1324 static int call_class_initializer_counter = 0; // for debugging
1325
class_initializer() const1326 Method* InstanceKlass::class_initializer() const {
1327 Method* clinit = find_method(
1328 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1329 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1330 return clinit;
1331 }
1332 return NULL;
1333 }
1334
call_class_initializer(TRAPS)1335 void InstanceKlass::call_class_initializer(TRAPS) {
1336 if (ReplayCompiles &&
1337 (ReplaySuppressInitializers == 1 ||
1338 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1339 // Hide the existence of the initializer for the purpose of replaying the compile
1340 return;
1341 }
1342
1343 methodHandle h_method(THREAD, class_initializer());
1344 assert(!is_initialized(), "we cannot initialize twice");
1345 LogTarget(Info, class, init) lt;
1346 if (lt.is_enabled()) {
1347 ResourceMark rm;
1348 LogStream ls(lt);
1349 ls.print("%d Initializing ", call_class_initializer_counter++);
1350 name()->print_value_on(&ls);
1351 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1352 }
1353 if (h_method() != NULL) {
1354 JavaCallArguments args; // No arguments
1355 JavaValue result(T_VOID);
1356 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1357 }
1358 }
1359
1360
mask_for(const methodHandle & method,int bci,InterpreterOopMap * entry_for)1361 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1362 InterpreterOopMap* entry_for) {
1363 // Lazily create the _oop_map_cache at first request
1364 // Lock-free access requires load_acquire.
1365 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1366 if (oop_map_cache == NULL) {
1367 MutexLocker x(OopMapCacheAlloc_lock);
1368 // Check if _oop_map_cache was allocated while we were waiting for this lock
1369 if ((oop_map_cache = _oop_map_cache) == NULL) {
1370 oop_map_cache = new OopMapCache();
1371 // Ensure _oop_map_cache is stable, since it is examined without a lock
1372 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1373 }
1374 }
1375 // _oop_map_cache is constant after init; lookup below does its own locking.
1376 oop_map_cache->lookup(method, bci, entry_for);
1377 }
1378
1379
find_local_field(Symbol * name,Symbol * sig,fieldDescriptor * fd) const1380 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1381 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1382 Symbol* f_name = fs.name();
1383 Symbol* f_sig = fs.signature();
1384 if (f_name == name && f_sig == sig) {
1385 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1386 return true;
1387 }
1388 }
1389 return false;
1390 }
1391
1392
find_interface_field(Symbol * name,Symbol * sig,fieldDescriptor * fd) const1393 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1394 const int n = local_interfaces()->length();
1395 for (int i = 0; i < n; i++) {
1396 Klass* intf1 = local_interfaces()->at(i);
1397 assert(intf1->is_interface(), "just checking type");
1398 // search for field in current interface
1399 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1400 assert(fd->is_static(), "interface field must be static");
1401 return intf1;
1402 }
1403 // search for field in direct superinterfaces
1404 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1405 if (intf2 != NULL) return intf2;
1406 }
1407 // otherwise field lookup fails
1408 return NULL;
1409 }
1410
1411
find_field(Symbol * name,Symbol * sig,fieldDescriptor * fd) const1412 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, 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 return const_cast<InstanceKlass*>(this);
1417 }
1418 // 2) search for field recursively in direct superinterfaces
1419 { Klass* intf = find_interface_field(name, sig, fd);
1420 if (intf != NULL) return intf;
1421 }
1422 // 3) apply field lookup recursively if superclass exists
1423 { Klass* supr = super();
1424 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1425 }
1426 // 4) otherwise field lookup fails
1427 return NULL;
1428 }
1429
1430
find_field(Symbol * name,Symbol * sig,bool is_static,fieldDescriptor * fd) const1431 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1432 // search order according to newest JVM spec (5.4.3.2, p.167).
1433 // 1) search for field in current klass
1434 if (find_local_field(name, sig, fd)) {
1435 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1436 }
1437 // 2) search for field recursively in direct superinterfaces
1438 if (is_static) {
1439 Klass* intf = find_interface_field(name, sig, fd);
1440 if (intf != NULL) return intf;
1441 }
1442 // 3) apply field lookup recursively if superclass exists
1443 { Klass* supr = super();
1444 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1445 }
1446 // 4) otherwise field lookup fails
1447 return NULL;
1448 }
1449
1450
find_local_field_from_offset(int offset,bool is_static,fieldDescriptor * fd) const1451 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1452 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1453 if (fs.offset() == offset) {
1454 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1455 if (fd->is_static() == is_static) return true;
1456 }
1457 }
1458 return false;
1459 }
1460
1461
find_field_from_offset(int offset,bool is_static,fieldDescriptor * fd) const1462 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1463 Klass* klass = const_cast<InstanceKlass*>(this);
1464 while (klass != NULL) {
1465 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1466 return true;
1467 }
1468 klass = klass->super();
1469 }
1470 return false;
1471 }
1472
1473
methods_do(void f (Method * method))1474 void InstanceKlass::methods_do(void f(Method* method)) {
1475 // Methods aren't stable until they are loaded. This can be read outside
1476 // a lock through the ClassLoaderData for profiling
1477 if (!is_loaded()) {
1478 return;
1479 }
1480
1481 int len = methods()->length();
1482 for (int index = 0; index < len; index++) {
1483 Method* m = methods()->at(index);
1484 assert(m->is_method(), "must be method");
1485 f(m);
1486 }
1487 }
1488
1489
do_local_static_fields(FieldClosure * cl)1490 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1491 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1492 if (fs.access_flags().is_static()) {
1493 fieldDescriptor& fd = fs.field_descriptor();
1494 cl->do_field(&fd);
1495 }
1496 }
1497 }
1498
1499
do_local_static_fields(void f (fieldDescriptor *,Handle,TRAPS),Handle mirror,TRAPS)1500 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1501 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1502 if (fs.access_flags().is_static()) {
1503 fieldDescriptor& fd = fs.field_descriptor();
1504 f(&fd, mirror, CHECK);
1505 }
1506 }
1507 }
1508
1509
compare_fields_by_offset(int * a,int * b)1510 static int compare_fields_by_offset(int* a, int* b) {
1511 return a[0] - b[0];
1512 }
1513
do_nonstatic_fields(FieldClosure * cl)1514 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1515 InstanceKlass* super = superklass();
1516 if (super != NULL) {
1517 super->do_nonstatic_fields(cl);
1518 }
1519 fieldDescriptor fd;
1520 int length = java_fields_count();
1521 // In DebugInfo nonstatic fields are sorted by offset.
1522 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1523 int j = 0;
1524 for (int i = 0; i < length; i += 1) {
1525 fd.reinitialize(this, i);
1526 if (!fd.is_static()) {
1527 fields_sorted[j + 0] = fd.offset();
1528 fields_sorted[j + 1] = i;
1529 j += 2;
1530 }
1531 }
1532 if (j > 0) {
1533 length = j;
1534 // _sort_Fn is defined in growableArray.hpp.
1535 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1536 for (int i = 0; i < length; i += 2) {
1537 fd.reinitialize(this, fields_sorted[i + 1]);
1538 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1539 cl->do_field(&fd);
1540 }
1541 }
1542 FREE_C_HEAP_ARRAY(int, fields_sorted);
1543 }
1544
1545
array_klasses_do(void f (Klass * k,TRAPS),TRAPS)1546 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1547 if (array_klasses() != NULL)
1548 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1549 }
1550
array_klasses_do(void f (Klass * k))1551 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1552 if (array_klasses() != NULL)
1553 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1554 }
1555
1556 #ifdef ASSERT
linear_search(const Array<Method * > * methods,const Symbol * name,const Symbol * signature)1557 static int linear_search(const Array<Method*>* methods,
1558 const Symbol* name,
1559 const Symbol* signature) {
1560 const int len = methods->length();
1561 for (int index = 0; index < len; index++) {
1562 const Method* const m = methods->at(index);
1563 assert(m->is_method(), "must be method");
1564 if (m->signature() == signature && m->name() == name) {
1565 return index;
1566 }
1567 }
1568 return -1;
1569 }
1570 #endif
1571
binary_search(const Array<Method * > * methods,const Symbol * name)1572 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1573 int len = methods->length();
1574 // methods are sorted, so do binary search
1575 int l = 0;
1576 int h = len - 1;
1577 while (l <= h) {
1578 int mid = (l + h) >> 1;
1579 Method* m = methods->at(mid);
1580 assert(m->is_method(), "must be method");
1581 int res = m->name()->fast_compare(name);
1582 if (res == 0) {
1583 return mid;
1584 } else if (res < 0) {
1585 l = mid + 1;
1586 } else {
1587 h = mid - 1;
1588 }
1589 }
1590 return -1;
1591 }
1592
1593 // find_method looks up the name/signature in the local methods array
find_method(const Symbol * name,const Symbol * signature) const1594 Method* InstanceKlass::find_method(const Symbol* name,
1595 const Symbol* signature) const {
1596 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1597 }
1598
find_method_impl(const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,StaticLookupMode static_mode,PrivateLookupMode private_mode) const1599 Method* InstanceKlass::find_method_impl(const Symbol* name,
1600 const Symbol* signature,
1601 OverpassLookupMode overpass_mode,
1602 StaticLookupMode static_mode,
1603 PrivateLookupMode private_mode) const {
1604 return InstanceKlass::find_method_impl(methods(),
1605 name,
1606 signature,
1607 overpass_mode,
1608 static_mode,
1609 private_mode);
1610 }
1611
1612 // find_instance_method looks up the name/signature in the local methods array
1613 // and skips over static methods
find_instance_method(const Array<Method * > * methods,const Symbol * name,const Symbol * signature,PrivateLookupMode private_mode)1614 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1615 const Symbol* name,
1616 const Symbol* signature,
1617 PrivateLookupMode private_mode) {
1618 Method* const meth = InstanceKlass::find_method_impl(methods,
1619 name,
1620 signature,
1621 find_overpass,
1622 skip_static,
1623 private_mode);
1624 assert(((meth == NULL) || !meth->is_static()),
1625 "find_instance_method should have skipped statics");
1626 return meth;
1627 }
1628
1629 // find_instance_method looks up the name/signature in the local methods array
1630 // and skips over static methods
find_instance_method(const Symbol * name,const Symbol * signature,PrivateLookupMode private_mode) const1631 Method* InstanceKlass::find_instance_method(const Symbol* name,
1632 const Symbol* signature,
1633 PrivateLookupMode private_mode) const {
1634 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1635 }
1636
1637 // Find looks up the name/signature in the local methods array
1638 // and filters on the overpass, static and private flags
1639 // This returns the first one found
1640 // note that the local methods array can have up to one overpass, one static
1641 // and one instance (private or not) with the same name/signature
find_local_method(const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,StaticLookupMode static_mode,PrivateLookupMode private_mode) const1642 Method* InstanceKlass::find_local_method(const Symbol* name,
1643 const Symbol* signature,
1644 OverpassLookupMode overpass_mode,
1645 StaticLookupMode static_mode,
1646 PrivateLookupMode private_mode) const {
1647 return InstanceKlass::find_method_impl(methods(),
1648 name,
1649 signature,
1650 overpass_mode,
1651 static_mode,
1652 private_mode);
1653 }
1654
1655 // Find looks up the name/signature in the local methods array
1656 // and filters on the overpass, static and private flags
1657 // This returns the first one found
1658 // note that the local methods array can have up to one overpass, one static
1659 // and one instance (private or not) with the same name/signature
find_local_method(const Array<Method * > * methods,const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,StaticLookupMode static_mode,PrivateLookupMode private_mode)1660 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1661 const Symbol* name,
1662 const Symbol* signature,
1663 OverpassLookupMode overpass_mode,
1664 StaticLookupMode static_mode,
1665 PrivateLookupMode private_mode) {
1666 return InstanceKlass::find_method_impl(methods,
1667 name,
1668 signature,
1669 overpass_mode,
1670 static_mode,
1671 private_mode);
1672 }
1673
find_method(const Array<Method * > * methods,const Symbol * name,const Symbol * signature)1674 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1675 const Symbol* name,
1676 const Symbol* signature) {
1677 return InstanceKlass::find_method_impl(methods,
1678 name,
1679 signature,
1680 find_overpass,
1681 find_static,
1682 find_private);
1683 }
1684
find_method_impl(const Array<Method * > * methods,const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,StaticLookupMode static_mode,PrivateLookupMode private_mode)1685 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1686 const Symbol* name,
1687 const Symbol* signature,
1688 OverpassLookupMode overpass_mode,
1689 StaticLookupMode static_mode,
1690 PrivateLookupMode private_mode) {
1691 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1692 return hit >= 0 ? methods->at(hit): NULL;
1693 }
1694
1695 // true if method matches signature and conforms to skipping_X conditions.
method_matches(const Method * m,const Symbol * signature,bool skipping_overpass,bool skipping_static,bool skipping_private)1696 static bool method_matches(const Method* m,
1697 const Symbol* signature,
1698 bool skipping_overpass,
1699 bool skipping_static,
1700 bool skipping_private) {
1701 return ((m->signature() == signature) &&
1702 (!skipping_overpass || !m->is_overpass()) &&
1703 (!skipping_static || !m->is_static()) &&
1704 (!skipping_private || !m->is_private()));
1705 }
1706
1707 // Used directly for default_methods to find the index into the
1708 // default_vtable_indices, and indirectly by find_method
1709 // find_method_index looks in the local methods array to return the index
1710 // of the matching name/signature. If, overpass methods are being ignored,
1711 // the search continues to find a potential non-overpass match. This capability
1712 // is important during method resolution to prefer a static method, for example,
1713 // over an overpass method.
1714 // There is the possibility in any _method's array to have the same name/signature
1715 // for a static method, an overpass method and a local instance method
1716 // To correctly catch a given method, the search criteria may need
1717 // to explicitly skip the other two. For local instance methods, it
1718 // is often necessary to skip private methods
find_method_index(const Array<Method * > * methods,const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,StaticLookupMode static_mode,PrivateLookupMode private_mode)1719 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1720 const Symbol* name,
1721 const Symbol* signature,
1722 OverpassLookupMode overpass_mode,
1723 StaticLookupMode static_mode,
1724 PrivateLookupMode private_mode) {
1725 const bool skipping_overpass = (overpass_mode == skip_overpass);
1726 const bool skipping_static = (static_mode == skip_static);
1727 const bool skipping_private = (private_mode == skip_private);
1728 const int hit = binary_search(methods, name);
1729 if (hit != -1) {
1730 const Method* const m = methods->at(hit);
1731
1732 // Do linear search to find matching signature. First, quick check
1733 // for common case, ignoring overpasses if requested.
1734 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1735 return hit;
1736 }
1737
1738 // search downwards through overloaded methods
1739 int i;
1740 for (i = hit - 1; i >= 0; --i) {
1741 const Method* const m = methods->at(i);
1742 assert(m->is_method(), "must be method");
1743 if (m->name() != name) {
1744 break;
1745 }
1746 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1747 return i;
1748 }
1749 }
1750 // search upwards
1751 for (i = hit + 1; i < methods->length(); ++i) {
1752 const Method* const m = methods->at(i);
1753 assert(m->is_method(), "must be method");
1754 if (m->name() != name) {
1755 break;
1756 }
1757 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1758 return i;
1759 }
1760 }
1761 // not found
1762 #ifdef ASSERT
1763 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1764 linear_search(methods, name, signature);
1765 assert(-1 == index, "binary search should have found entry %d", index);
1766 #endif
1767 }
1768 return -1;
1769 }
1770
find_method_by_name(const Symbol * name,int * end) const1771 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1772 return find_method_by_name(methods(), name, end);
1773 }
1774
find_method_by_name(const Array<Method * > * methods,const Symbol * name,int * end_ptr)1775 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1776 const Symbol* name,
1777 int* end_ptr) {
1778 assert(end_ptr != NULL, "just checking");
1779 int start = binary_search(methods, name);
1780 int end = start + 1;
1781 if (start != -1) {
1782 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1783 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1784 *end_ptr = end;
1785 return start;
1786 }
1787 return -1;
1788 }
1789
1790 // uncached_lookup_method searches both the local class methods array and all
1791 // superclasses methods arrays, skipping any overpass methods in superclasses,
1792 // and possibly skipping private methods.
uncached_lookup_method(const Symbol * name,const Symbol * signature,OverpassLookupMode overpass_mode,PrivateLookupMode private_mode) const1793 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1794 const Symbol* signature,
1795 OverpassLookupMode overpass_mode,
1796 PrivateLookupMode private_mode) const {
1797 OverpassLookupMode overpass_local_mode = overpass_mode;
1798 const Klass* klass = this;
1799 while (klass != NULL) {
1800 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1801 signature,
1802 overpass_local_mode,
1803 find_static,
1804 private_mode);
1805 if (method != NULL) {
1806 return method;
1807 }
1808 klass = klass->super();
1809 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1810 }
1811 return NULL;
1812 }
1813
1814 #ifdef ASSERT
1815 // search through class hierarchy and return true if this class or
1816 // one of the superclasses was redefined
has_redefined_this_or_super() const1817 bool InstanceKlass::has_redefined_this_or_super() const {
1818 const Klass* klass = this;
1819 while (klass != NULL) {
1820 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1821 return true;
1822 }
1823 klass = klass->super();
1824 }
1825 return false;
1826 }
1827 #endif
1828
1829 // lookup a method in the default methods list then in all transitive interfaces
1830 // Do NOT return private or static methods
lookup_method_in_ordered_interfaces(Symbol * name,Symbol * signature) const1831 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1832 Symbol* signature) const {
1833 Method* m = NULL;
1834 if (default_methods() != NULL) {
1835 m = find_method(default_methods(), name, signature);
1836 }
1837 // Look up interfaces
1838 if (m == NULL) {
1839 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1840 }
1841 return m;
1842 }
1843
1844 // lookup a method in all the interfaces that this class implements
1845 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1846 // They should only be found in the initial InterfaceMethodRef
lookup_method_in_all_interfaces(Symbol * name,Symbol * signature,DefaultsLookupMode defaults_mode) const1847 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1848 Symbol* signature,
1849 DefaultsLookupMode defaults_mode) const {
1850 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1851 int num_ifs = all_ifs->length();
1852 InstanceKlass *ik = NULL;
1853 for (int i = 0; i < num_ifs; i++) {
1854 ik = all_ifs->at(i);
1855 Method* m = ik->lookup_method(name, signature);
1856 if (m != NULL && m->is_public() && !m->is_static() &&
1857 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1858 return m;
1859 }
1860 }
1861 return NULL;
1862 }
1863
1864 /* jni_id_for_impl for jfieldIds only */
jni_id_for_impl(int offset)1865 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1866 MutexLocker ml(JfieldIdCreation_lock);
1867 // Retry lookup after we got the lock
1868 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1869 if (probe == NULL) {
1870 // Slow case, allocate new static field identifier
1871 probe = new JNIid(this, offset, jni_ids());
1872 set_jni_ids(probe);
1873 }
1874 return probe;
1875 }
1876
1877
1878 /* jni_id_for for jfieldIds only */
jni_id_for(int offset)1879 JNIid* InstanceKlass::jni_id_for(int offset) {
1880 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1881 if (probe == NULL) {
1882 probe = jni_id_for_impl(offset);
1883 }
1884 return probe;
1885 }
1886
enclosing_method_data(int offset) const1887 u2 InstanceKlass::enclosing_method_data(int offset) const {
1888 const Array<jushort>* const inner_class_list = inner_classes();
1889 if (inner_class_list == NULL) {
1890 return 0;
1891 }
1892 const int length = inner_class_list->length();
1893 if (length % inner_class_next_offset == 0) {
1894 return 0;
1895 }
1896 const int index = length - enclosing_method_attribute_size;
1897 assert(offset < enclosing_method_attribute_size, "invalid offset");
1898 return inner_class_list->at(index + offset);
1899 }
1900
set_enclosing_method_indices(u2 class_index,u2 method_index)1901 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1902 u2 method_index) {
1903 Array<jushort>* inner_class_list = inner_classes();
1904 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1905 int length = inner_class_list->length();
1906 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1907 int index = length - enclosing_method_attribute_size;
1908 inner_class_list->at_put(
1909 index + enclosing_method_class_index_offset, class_index);
1910 inner_class_list->at_put(
1911 index + enclosing_method_method_index_offset, method_index);
1912 }
1913 }
1914
1915 // Lookup or create a jmethodID.
1916 // This code is called by the VMThread and JavaThreads so the
1917 // locking has to be done very carefully to avoid deadlocks
1918 // and/or other cache consistency problems.
1919 //
get_jmethod_id(const methodHandle & method_h)1920 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1921 size_t idnum = (size_t)method_h->method_idnum();
1922 jmethodID* jmeths = methods_jmethod_ids_acquire();
1923 size_t length = 0;
1924 jmethodID id = NULL;
1925
1926 // We use a double-check locking idiom here because this cache is
1927 // performance sensitive. In the normal system, this cache only
1928 // transitions from NULL to non-NULL which is safe because we use
1929 // release_set_methods_jmethod_ids() to advertise the new cache.
1930 // A partially constructed cache should never be seen by a racing
1931 // thread. We also use release_store() to save a new jmethodID
1932 // in the cache so a partially constructed jmethodID should never be
1933 // seen either. Cache reads of existing jmethodIDs proceed without a
1934 // lock, but cache writes of a new jmethodID requires uniqueness and
1935 // creation of the cache itself requires no leaks so a lock is
1936 // generally acquired in those two cases.
1937 //
1938 // If the RedefineClasses() API has been used, then this cache can
1939 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1940 // Cache creation requires no leaks and we require safety between all
1941 // cache accesses and freeing of the old cache so a lock is generally
1942 // acquired when the RedefineClasses() API has been used.
1943
1944 if (jmeths != NULL) {
1945 // the cache already exists
1946 if (!idnum_can_increment()) {
1947 // the cache can't grow so we can just get the current values
1948 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1949 } else {
1950 // cache can grow so we have to be more careful
1951 if (Threads::number_of_threads() == 0 ||
1952 SafepointSynchronize::is_at_safepoint()) {
1953 // we're single threaded or at a safepoint - no locking needed
1954 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1955 } else {
1956 MutexLocker ml(JmethodIdCreation_lock);
1957 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1958 }
1959 }
1960 }
1961 // implied else:
1962 // we need to allocate a cache so default length and id values are good
1963
1964 if (jmeths == NULL || // no cache yet
1965 length <= idnum || // cache is too short
1966 id == NULL) { // cache doesn't contain entry
1967
1968 // This function can be called by the VMThread so we have to do all
1969 // things that might block on a safepoint before grabbing the lock.
1970 // Otherwise, we can deadlock with the VMThread or have a cache
1971 // consistency issue. These vars keep track of what we might have
1972 // to free after the lock is dropped.
1973 jmethodID to_dealloc_id = NULL;
1974 jmethodID* to_dealloc_jmeths = NULL;
1975
1976 // may not allocate new_jmeths or use it if we allocate it
1977 jmethodID* new_jmeths = NULL;
1978 if (length <= idnum) {
1979 // allocate a new cache that might be used
1980 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1981 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1982 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1983 // cache size is stored in element[0], other elements offset by one
1984 new_jmeths[0] = (jmethodID)size;
1985 }
1986
1987 // allocate a new jmethodID that might be used
1988 jmethodID new_id = NULL;
1989 if (method_h->is_old() && !method_h->is_obsolete()) {
1990 // The method passed in is old (but not obsolete), we need to use the current version
1991 Method* current_method = method_with_idnum((int)idnum);
1992 assert(current_method != NULL, "old and but not obsolete, so should exist");
1993 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1994 } else {
1995 // It is the current version of the method or an obsolete method,
1996 // use the version passed in
1997 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1998 }
1999
2000 if (Threads::number_of_threads() == 0 ||
2001 SafepointSynchronize::is_at_safepoint()) {
2002 // we're single threaded or at a safepoint - no locking needed
2003 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2004 &to_dealloc_id, &to_dealloc_jmeths);
2005 } else {
2006 MutexLocker ml(JmethodIdCreation_lock);
2007 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2008 &to_dealloc_id, &to_dealloc_jmeths);
2009 }
2010
2011 // The lock has been dropped so we can free resources.
2012 // Free up either the old cache or the new cache if we allocated one.
2013 if (to_dealloc_jmeths != NULL) {
2014 FreeHeap(to_dealloc_jmeths);
2015 }
2016 // free up the new ID since it wasn't needed
2017 if (to_dealloc_id != NULL) {
2018 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2019 }
2020 }
2021 return id;
2022 }
2023
2024 // Figure out how many jmethodIDs haven't been allocated, and make
2025 // sure space for them is pre-allocated. This makes getting all
2026 // method ids much, much faster with classes with more than 8
2027 // methods, and has a *substantial* effect on performance with jvmti
2028 // code that loads all jmethodIDs for all classes.
ensure_space_for_methodids(int start_offset)2029 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2030 int new_jmeths = 0;
2031 int length = methods()->length();
2032 for (int index = start_offset; index < length; index++) {
2033 Method* m = methods()->at(index);
2034 jmethodID id = m->find_jmethod_id_or_null();
2035 if (id == NULL) {
2036 new_jmeths++;
2037 }
2038 }
2039 if (new_jmeths != 0) {
2040 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2041 }
2042 }
2043
2044 // Common code to fetch the jmethodID from the cache or update the
2045 // cache with the new jmethodID. This function should never do anything
2046 // that causes the caller to go to a safepoint or we can deadlock with
2047 // the VMThread or have cache consistency issues.
2048 //
get_jmethod_id_fetch_or_update(size_t idnum,jmethodID new_id,jmethodID * new_jmeths,jmethodID * to_dealloc_id_p,jmethodID ** to_dealloc_jmeths_p)2049 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2050 size_t idnum, jmethodID new_id,
2051 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2052 jmethodID** to_dealloc_jmeths_p) {
2053 assert(new_id != NULL, "sanity check");
2054 assert(to_dealloc_id_p != NULL, "sanity check");
2055 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2056 assert(Threads::number_of_threads() == 0 ||
2057 SafepointSynchronize::is_at_safepoint() ||
2058 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2059
2060 // reacquire the cache - we are locked, single threaded or at a safepoint
2061 jmethodID* jmeths = methods_jmethod_ids_acquire();
2062 jmethodID id = NULL;
2063 size_t length = 0;
2064
2065 if (jmeths == NULL || // no cache yet
2066 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2067 if (jmeths != NULL) {
2068 // copy any existing entries from the old cache
2069 for (size_t index = 0; index < length; index++) {
2070 new_jmeths[index+1] = jmeths[index+1];
2071 }
2072 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2073 }
2074 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2075 } else {
2076 // fetch jmethodID (if any) from the existing cache
2077 id = jmeths[idnum+1];
2078 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2079 }
2080 if (id == NULL) {
2081 // No matching jmethodID in the existing cache or we have a new
2082 // cache or we just grew the cache. This cache write is done here
2083 // by the first thread to win the foot race because a jmethodID
2084 // needs to be unique once it is generally available.
2085 id = new_id;
2086
2087 // The jmethodID cache can be read while unlocked so we have to
2088 // make sure the new jmethodID is complete before installing it
2089 // in the cache.
2090 OrderAccess::release_store(&jmeths[idnum+1], id);
2091 } else {
2092 *to_dealloc_id_p = new_id; // save new id for later delete
2093 }
2094 return id;
2095 }
2096
2097
2098 // Common code to get the jmethodID cache length and the jmethodID
2099 // value at index idnum if there is one.
2100 //
get_jmethod_id_length_value(jmethodID * cache,size_t idnum,size_t * length_p,jmethodID * id_p)2101 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2102 size_t idnum, size_t *length_p, jmethodID* id_p) {
2103 assert(cache != NULL, "sanity check");
2104 assert(length_p != NULL, "sanity check");
2105 assert(id_p != NULL, "sanity check");
2106
2107 // cache size is stored in element[0], other elements offset by one
2108 *length_p = (size_t)cache[0];
2109 if (*length_p <= idnum) { // cache is too short
2110 *id_p = NULL;
2111 } else {
2112 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2113 }
2114 }
2115
2116
2117 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
jmethod_id_or_null(Method * method)2118 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2119 size_t idnum = (size_t)method->method_idnum();
2120 jmethodID* jmeths = methods_jmethod_ids_acquire();
2121 size_t length; // length assigned as debugging crumb
2122 jmethodID id = NULL;
2123 if (jmeths != NULL && // If there is a cache
2124 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2125 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2126 }
2127 return id;
2128 }
2129
dependencies()2130 inline DependencyContext InstanceKlass::dependencies() {
2131 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2132 return dep_context;
2133 }
2134
mark_dependent_nmethods(KlassDepChange & changes)2135 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2136 return dependencies().mark_dependent_nmethods(changes);
2137 }
2138
add_dependent_nmethod(nmethod * nm)2139 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2140 dependencies().add_dependent_nmethod(nm);
2141 }
2142
remove_dependent_nmethod(nmethod * nm)2143 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2144 dependencies().remove_dependent_nmethod(nm);
2145 }
2146
clean_dependency_context()2147 void InstanceKlass::clean_dependency_context() {
2148 dependencies().clean_unloading_dependents();
2149 }
2150
2151 #ifndef PRODUCT
print_dependent_nmethods(bool verbose)2152 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2153 dependencies().print_dependent_nmethods(verbose);
2154 }
2155
is_dependent_nmethod(nmethod * nm)2156 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2157 return dependencies().is_dependent_nmethod(nm);
2158 }
2159 #endif //PRODUCT
2160
clean_weak_instanceklass_links()2161 void InstanceKlass::clean_weak_instanceklass_links() {
2162 clean_implementors_list();
2163 clean_method_data();
2164 }
2165
clean_implementors_list()2166 void InstanceKlass::clean_implementors_list() {
2167 assert(is_loader_alive(), "this klass should be live");
2168 if (is_interface()) {
2169 assert (ClassUnloading, "only called for ClassUnloading");
2170 for (;;) {
2171 // Use load_acquire due to competing with inserts
2172 Klass* impl = OrderAccess::load_acquire(adr_implementor());
2173 if (impl != NULL && !impl->is_loader_alive()) {
2174 // NULL this field, might be an unloaded klass or NULL
2175 Klass* volatile* klass = adr_implementor();
2176 if (Atomic::cmpxchg((Klass*)NULL, klass, impl) == impl) {
2177 // Successfully unlinking implementor.
2178 if (log_is_enabled(Trace, class, unload)) {
2179 ResourceMark rm;
2180 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2181 }
2182 return;
2183 }
2184 } else {
2185 return;
2186 }
2187 }
2188 }
2189 }
2190
clean_method_data()2191 void InstanceKlass::clean_method_data() {
2192 for (int m = 0; m < methods()->length(); m++) {
2193 MethodData* mdo = methods()->at(m)->method_data();
2194 if (mdo != NULL) {
2195 MutexLockerEx ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock());
2196 mdo->clean_method_data(/*always_clean*/false);
2197 }
2198 }
2199 }
2200
supers_have_passed_fingerprint_checks()2201 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2202 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2203 ResourceMark rm;
2204 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2205 return false;
2206 }
2207
2208 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2209 if (local_interfaces != NULL) {
2210 int length = local_interfaces->length();
2211 for (int i = 0; i < length; i++) {
2212 InstanceKlass* intf = local_interfaces->at(i);
2213 if (!intf->has_passed_fingerprint_check()) {
2214 ResourceMark rm;
2215 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2216 return false;
2217 }
2218 }
2219 }
2220
2221 return true;
2222 }
2223
should_store_fingerprint(bool is_unsafe_anonymous)2224 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2225 #if INCLUDE_AOT
2226 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2227 if (CalculateClassFingerprint) {
2228 // (1) We are running AOT to generate a shared library.
2229 return true;
2230 }
2231 if (DumpSharedSpaces) {
2232 // (2) We are running -Xshare:dump to create a shared archive
2233 return true;
2234 }
2235 if (UseAOT && is_unsafe_anonymous) {
2236 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2237 return true;
2238 }
2239 #endif
2240
2241 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2242 // but do not store the 64-bit fingerprint to save space.
2243 return false;
2244 }
2245
has_stored_fingerprint() const2246 bool InstanceKlass::has_stored_fingerprint() const {
2247 #if INCLUDE_AOT
2248 return should_store_fingerprint() || is_shared();
2249 #else
2250 return false;
2251 #endif
2252 }
2253
get_stored_fingerprint() const2254 uint64_t InstanceKlass::get_stored_fingerprint() const {
2255 address adr = adr_fingerprint();
2256 if (adr != NULL) {
2257 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2258 }
2259 return 0;
2260 }
2261
store_fingerprint(uint64_t fingerprint)2262 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2263 address adr = adr_fingerprint();
2264 if (adr != NULL) {
2265 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2266
2267 ResourceMark rm;
2268 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2269 }
2270 }
2271
metaspace_pointers_do(MetaspaceClosure * it)2272 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2273 Klass::metaspace_pointers_do(it);
2274
2275 if (log_is_enabled(Trace, cds)) {
2276 ResourceMark rm;
2277 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2278 }
2279
2280 it->push(&_annotations);
2281 it->push((Klass**)&_array_klasses);
2282 it->push(&_constants);
2283 it->push(&_inner_classes);
2284 it->push(&_array_name);
2285 #if INCLUDE_JVMTI
2286 it->push(&_previous_versions);
2287 #endif
2288 it->push(&_methods);
2289 it->push(&_default_methods);
2290 it->push(&_local_interfaces);
2291 it->push(&_transitive_interfaces);
2292 it->push(&_method_ordering);
2293 it->push(&_default_vtable_indices);
2294 it->push(&_fields);
2295
2296 if (itable_length() > 0) {
2297 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2298 int method_table_offset_in_words = ioe->offset()/wordSize;
2299 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2300 / itableOffsetEntry::size();
2301
2302 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2303 if (ioe->interface_klass() != NULL) {
2304 it->push(ioe->interface_klass_addr());
2305 itableMethodEntry* ime = ioe->first_method_entry(this);
2306 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2307 for (int index = 0; index < n; index ++) {
2308 it->push(ime[index].method_addr());
2309 }
2310 }
2311 }
2312 }
2313
2314 it->push(&_nest_members);
2315 }
2316
remove_unshareable_info()2317 void InstanceKlass::remove_unshareable_info() {
2318 Klass::remove_unshareable_info();
2319
2320 if (is_in_error_state()) {
2321 // Classes are attempted to link during dumping and may fail,
2322 // but these classes are still in the dictionary and class list in CLD.
2323 // Check in_error state first because in_error is > linked state, so
2324 // is_linked() is true.
2325 // If there's a linking error, there is nothing else to remove.
2326 return;
2327 }
2328
2329 // Reset to the 'allocated' state to prevent any premature accessing to
2330 // a shared class at runtime while the class is still being loaded and
2331 // restored. A class' init_state is set to 'loaded' at runtime when it's
2332 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2333 _init_state = allocated;
2334
2335 {
2336 MutexLocker ml(Compile_lock);
2337 init_implementor();
2338 }
2339
2340 constants()->remove_unshareable_info();
2341
2342 for (int i = 0; i < methods()->length(); i++) {
2343 Method* m = methods()->at(i);
2344 m->remove_unshareable_info();
2345 }
2346
2347 // do array classes also.
2348 if (array_klasses() != NULL) {
2349 array_klasses()->remove_unshareable_info();
2350 }
2351
2352 // These are not allocated from metaspace, but they should should all be empty
2353 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2354 guarantee(_source_debug_extension == NULL, "must be");
2355 guarantee(_dep_context == NULL, "must be");
2356 guarantee(_osr_nmethods_head == NULL, "must be");
2357
2358 #if INCLUDE_JVMTI
2359 guarantee(_breakpoints == NULL, "must be");
2360 guarantee(_previous_versions == NULL, "must be");
2361 #endif
2362
2363 _init_thread = NULL;
2364 _methods_jmethod_ids = NULL;
2365 _jni_ids = NULL;
2366 _oop_map_cache = NULL;
2367 // clear _nest_host to ensure re-load at runtime
2368 _nest_host = NULL;
2369 }
2370
remove_java_mirror()2371 void InstanceKlass::remove_java_mirror() {
2372 Klass::remove_java_mirror();
2373
2374 // do array classes also.
2375 if (array_klasses() != NULL) {
2376 array_klasses()->remove_java_mirror();
2377 }
2378 }
2379
restore_unshareable_info(ClassLoaderData * loader_data,Handle protection_domain,TRAPS)2380 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2381 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2382 // before the InstanceKlass is added to the SystemDictionary. Make
2383 // sure the current state is <loaded.
2384 assert(!is_loaded(), "invalid init state");
2385 set_package(loader_data, CHECK);
2386 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2387
2388 Array<Method*>* methods = this->methods();
2389 int num_methods = methods->length();
2390 for (int index2 = 0; index2 < num_methods; ++index2) {
2391 methodHandle m(THREAD, methods->at(index2));
2392 m->restore_unshareable_info(CHECK);
2393 }
2394 if (JvmtiExport::has_redefined_a_class()) {
2395 // Reinitialize vtable because RedefineClasses may have changed some
2396 // entries in this vtable for super classes so the CDS vtable might
2397 // point to old or obsolete entries. RedefineClasses doesn't fix up
2398 // vtables in the shared system dictionary, only the main one.
2399 // It also redefines the itable too so fix that too.
2400 vtable().initialize_vtable(false, CHECK);
2401 itable().initialize_itable(false, CHECK);
2402 }
2403
2404 // restore constant pool resolved references
2405 constants()->restore_unshareable_info(CHECK);
2406
2407 if (array_klasses() != NULL) {
2408 // Array classes have null protection domain.
2409 // --> see ArrayKlass::complete_create_array_klass()
2410 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2411 }
2412 }
2413
2414 // returns true IFF is_in_error_state() has been changed as a result of this call.
check_sharing_error_state()2415 bool InstanceKlass::check_sharing_error_state() {
2416 assert(DumpSharedSpaces, "should only be called during dumping");
2417 bool old_state = is_in_error_state();
2418
2419 if (!is_in_error_state()) {
2420 bool bad = false;
2421 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2422 if (sup->is_in_error_state()) {
2423 bad = true;
2424 break;
2425 }
2426 }
2427 if (!bad) {
2428 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2429 for (int i = 0; i < interfaces->length(); i++) {
2430 InstanceKlass* iface = interfaces->at(i);
2431 if (iface->is_in_error_state()) {
2432 bad = true;
2433 break;
2434 }
2435 }
2436 }
2437
2438 if (bad) {
2439 set_in_error_state();
2440 }
2441 }
2442
2443 return (old_state != is_in_error_state());
2444 }
2445
2446 #if INCLUDE_JVMTI
clear_all_breakpoints(Method * m)2447 static void clear_all_breakpoints(Method* m) {
2448 m->clear_all_breakpoints();
2449 }
2450 #endif
2451
unload_class(InstanceKlass * ik)2452 void InstanceKlass::unload_class(InstanceKlass* ik) {
2453 // Release dependencies.
2454 ik->dependencies().remove_all_dependents();
2455
2456 // notify the debugger
2457 if (JvmtiExport::should_post_class_unload()) {
2458 JvmtiExport::post_class_unload(ik);
2459 }
2460
2461 // notify ClassLoadingService of class unload
2462 ClassLoadingService::notify_class_unloaded(ik);
2463
2464 #if INCLUDE_JFR
2465 assert(ik != NULL, "invariant");
2466 EventClassUnload event;
2467 event.set_unloadedClass(ik);
2468 event.set_definingClassLoader(ik->class_loader_data());
2469 event.commit();
2470 #endif
2471 }
2472
release_C_heap_structures(InstanceKlass * ik)2473 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2474 // Clean up C heap
2475 ik->release_C_heap_structures();
2476 ik->constants()->release_C_heap_structures();
2477 }
2478
release_C_heap_structures()2479 void InstanceKlass::release_C_heap_structures() {
2480 // Can't release the constant pool here because the constant pool can be
2481 // deallocated separately from the InstanceKlass for default methods and
2482 // redefine classes.
2483
2484 // Deallocate oop map cache
2485 if (_oop_map_cache != NULL) {
2486 delete _oop_map_cache;
2487 _oop_map_cache = NULL;
2488 }
2489
2490 // Deallocate JNI identifiers for jfieldIDs
2491 JNIid::deallocate(jni_ids());
2492 set_jni_ids(NULL);
2493
2494 jmethodID* jmeths = methods_jmethod_ids_acquire();
2495 if (jmeths != (jmethodID*)NULL) {
2496 release_set_methods_jmethod_ids(NULL);
2497 FreeHeap(jmeths);
2498 }
2499
2500 assert(_dep_context == NULL,
2501 "dependencies should already be cleaned");
2502
2503 #if INCLUDE_JVMTI
2504 // Deallocate breakpoint records
2505 if (breakpoints() != 0x0) {
2506 methods_do(clear_all_breakpoints);
2507 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2508 }
2509
2510 // deallocate the cached class file
2511 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2512 os::free(_cached_class_file);
2513 _cached_class_file = NULL;
2514 }
2515 #endif
2516
2517 // Decrement symbol reference counts associated with the unloaded class.
2518 if (_name != NULL) _name->decrement_refcount();
2519 // unreference array name derived from this class name (arrays of an unloaded
2520 // class can't be referenced anymore).
2521 if (_array_name != NULL) _array_name->decrement_refcount();
2522 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2523 }
2524
set_source_debug_extension(const char * array,int length)2525 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2526 if (array == NULL) {
2527 _source_debug_extension = NULL;
2528 } else {
2529 // Adding one to the attribute length in order to store a null terminator
2530 // character could cause an overflow because the attribute length is
2531 // already coded with an u4 in the classfile, but in practice, it's
2532 // unlikely to happen.
2533 assert((length+1) > length, "Overflow checking");
2534 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2535 for (int i = 0; i < length; i++) {
2536 sde[i] = array[i];
2537 }
2538 sde[length] = '\0';
2539 _source_debug_extension = sde;
2540 }
2541 }
2542
signature_name() const2543 const char* InstanceKlass::signature_name() const {
2544 int hash_len = 0;
2545 char hash_buf[40];
2546
2547 // If this is an unsafe anonymous class, append a hash to make the name unique
2548 if (is_unsafe_anonymous()) {
2549 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2550 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2551 hash_len = (int)strlen(hash_buf);
2552 }
2553
2554 // Get the internal name as a c string
2555 const char* src = (const char*) (name()->as_C_string());
2556 const int src_length = (int)strlen(src);
2557
2558 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2559
2560 // Add L as type indicator
2561 int dest_index = 0;
2562 dest[dest_index++] = 'L';
2563
2564 // Add the actual class name
2565 for (int src_index = 0; src_index < src_length; ) {
2566 dest[dest_index++] = src[src_index++];
2567 }
2568
2569 // If we have a hash, append it
2570 for (int hash_index = 0; hash_index < hash_len; ) {
2571 dest[dest_index++] = hash_buf[hash_index++];
2572 }
2573
2574 // Add the semicolon and the NULL
2575 dest[dest_index++] = ';';
2576 dest[dest_index] = '\0';
2577 return dest;
2578 }
2579
2580 // Used to obtain the package name from a fully qualified class name.
package_from_name(const Symbol * name,TRAPS)2581 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2582 if (name == NULL) {
2583 return NULL;
2584 } else {
2585 if (name->utf8_length() <= 0) {
2586 return NULL;
2587 }
2588 ResourceMark rm;
2589 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2590 if (package_name == NULL) {
2591 return NULL;
2592 }
2593 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2594 return pkg_name;
2595 }
2596 }
2597
module() const2598 ModuleEntry* InstanceKlass::module() const {
2599 // For an unsafe anonymous class return the host class' module
2600 if (is_unsafe_anonymous()) {
2601 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2602 return unsafe_anonymous_host()->module();
2603 }
2604
2605 // Class is in a named package
2606 if (!in_unnamed_package()) {
2607 return _package_entry->module();
2608 }
2609
2610 // Class is in an unnamed package, return its loader's unnamed module
2611 return class_loader_data()->unnamed_module();
2612 }
2613
set_package(ClassLoaderData * loader_data,TRAPS)2614 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2615
2616 // ensure java/ packages only loaded by boot or platform builtin loaders
2617 check_prohibited_package(name(), loader_data, CHECK);
2618
2619 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2620
2621 if (pkg_name != NULL && loader_data != NULL) {
2622
2623 // Find in class loader's package entry table.
2624 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2625
2626 // If the package name is not found in the loader's package
2627 // entry table, it is an indication that the package has not
2628 // been defined. Consider it defined within the unnamed module.
2629 if (_package_entry == NULL) {
2630 ResourceMark rm;
2631
2632 if (!ModuleEntryTable::javabase_defined()) {
2633 // Before java.base is defined during bootstrapping, define all packages in
2634 // the java.base module. If a non-java.base package is erroneously placed
2635 // in the java.base module it will be caught later when java.base
2636 // is defined by ModuleEntryTable::verify_javabase_packages check.
2637 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2638 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2639 } else {
2640 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2641 _package_entry = loader_data->packages()->lookup(pkg_name,
2642 loader_data->unnamed_module());
2643 }
2644
2645 // A package should have been successfully created
2646 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2647 name()->as_C_string(), loader_data->loader_name_and_id());
2648 }
2649
2650 if (log_is_enabled(Debug, module)) {
2651 ResourceMark rm;
2652 ModuleEntry* m = _package_entry->module();
2653 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2654 external_name(),
2655 pkg_name->as_C_string(),
2656 loader_data->loader_name_and_id(),
2657 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2658 }
2659 } else {
2660 ResourceMark rm;
2661 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2662 external_name(),
2663 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2664 UNNAMED_MODULE);
2665 }
2666 }
2667
2668
2669 // different versions of is_same_class_package
2670
is_same_class_package(const Klass * class2) const2671 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2672 oop classloader1 = this->class_loader();
2673 PackageEntry* classpkg1 = this->package();
2674 if (class2->is_objArray_klass()) {
2675 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2676 }
2677
2678 oop classloader2;
2679 PackageEntry* classpkg2;
2680 if (class2->is_instance_klass()) {
2681 classloader2 = class2->class_loader();
2682 classpkg2 = class2->package();
2683 } else {
2684 assert(class2->is_typeArray_klass(), "should be type array");
2685 classloader2 = NULL;
2686 classpkg2 = NULL;
2687 }
2688
2689 // Same package is determined by comparing class loader
2690 // and package entries. Both must be the same. This rule
2691 // applies even to classes that are defined in the unnamed
2692 // package, they still must have the same class loader.
2693 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2694 return true;
2695 }
2696
2697 return false;
2698 }
2699
2700 // return true if this class and other_class are in the same package. Classloader
2701 // and classname information is enough to determine a class's package
is_same_class_package(oop other_class_loader,const Symbol * other_class_name) const2702 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2703 const Symbol* other_class_name) const {
2704 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2705 return false;
2706 }
2707 if (name()->fast_compare(other_class_name) == 0) {
2708 return true;
2709 }
2710
2711 {
2712 ResourceMark rm;
2713
2714 bool bad_class_name = false;
2715 const char* other_pkg =
2716 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2717 if (bad_class_name) {
2718 return false;
2719 }
2720 // Check that package_from_name() returns NULL, not "", if there is no package.
2721 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2722
2723 const Symbol* const this_package_name =
2724 this->package() != NULL ? this->package()->name() : NULL;
2725
2726 if (this_package_name == NULL || other_pkg == NULL) {
2727 // One of the two doesn't have a package. Only return true if the other
2728 // one also doesn't have a package.
2729 return (const char*)this_package_name == other_pkg;
2730 }
2731
2732 // Check if package is identical
2733 return this_package_name->equals(other_pkg);
2734 }
2735 }
2736
2737 // Returns true iff super_method can be overridden by a method in targetclassname
2738 // See JLS 3rd edition 8.4.6.1
2739 // Assumes name-signature match
2740 // "this" is InstanceKlass of super_method which must exist
2741 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
is_override(const methodHandle & super_method,Handle targetclassloader,Symbol * targetclassname,TRAPS)2742 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2743 // Private methods can not be overridden
2744 if (super_method->is_private()) {
2745 return false;
2746 }
2747 // If super method is accessible, then override
2748 if ((super_method->is_protected()) ||
2749 (super_method->is_public())) {
2750 return true;
2751 }
2752 // Package-private methods are not inherited outside of package
2753 assert(super_method->is_package_private(), "must be package private");
2754 return(is_same_class_package(targetclassloader(), targetclassname));
2755 }
2756
2757 // Only boot and platform class loaders can define classes in "java/" packages.
check_prohibited_package(Symbol * class_name,ClassLoaderData * loader_data,TRAPS)2758 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2759 ClassLoaderData* loader_data,
2760 TRAPS) {
2761 if (!loader_data->is_boot_class_loader_data() &&
2762 !loader_data->is_platform_class_loader_data() &&
2763 class_name != NULL) {
2764 ResourceMark rm(THREAD);
2765 char* name = class_name->as_C_string();
2766 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2767 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2768 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2769 name = pkg_name->as_C_string();
2770 const char* class_loader_name = loader_data->loader_name_and_id();
2771 StringUtils::replace_no_expand(name, "/", ".");
2772 const char* msg_text1 = "Class loader (instance of): ";
2773 const char* msg_text2 = " tried to load prohibited package name: ";
2774 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2775 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2776 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2777 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2778 }
2779 }
2780 return;
2781 }
2782
find_inner_classes_attr(int * ooff,int * noff,TRAPS) const2783 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2784 constantPoolHandle i_cp(THREAD, constants());
2785 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2786 int ioff = iter.inner_class_info_index();
2787 if (ioff != 0) {
2788 // Check to see if the name matches the class we're looking for
2789 // before attempting to find the class.
2790 if (i_cp->klass_name_at_matches(this, ioff)) {
2791 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2792 if (this == inner_klass) {
2793 *ooff = iter.outer_class_info_index();
2794 *noff = iter.inner_name_index();
2795 return true;
2796 }
2797 }
2798 }
2799 }
2800 return false;
2801 }
2802
compute_enclosing_class(bool * inner_is_member,TRAPS) const2803 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2804 InstanceKlass* outer_klass = NULL;
2805 *inner_is_member = false;
2806 int ooff = 0, noff = 0;
2807 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2808 if (has_inner_classes_attr) {
2809 constantPoolHandle i_cp(THREAD, constants());
2810 if (ooff != 0) {
2811 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2812 outer_klass = InstanceKlass::cast(ok);
2813 *inner_is_member = true;
2814 }
2815 if (NULL == outer_klass) {
2816 // It may be unsafe anonymous; try for that.
2817 int encl_method_class_idx = enclosing_method_class_index();
2818 if (encl_method_class_idx != 0) {
2819 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2820 outer_klass = InstanceKlass::cast(ok);
2821 *inner_is_member = false;
2822 }
2823 }
2824 }
2825
2826 // If no inner class attribute found for this class.
2827 if (NULL == outer_klass) return NULL;
2828
2829 // Throws an exception if outer klass has not declared k as an inner klass
2830 // We need evidence that each klass knows about the other, or else
2831 // the system could allow a spoof of an inner class to gain access rights.
2832 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2833 return outer_klass;
2834 }
2835
compute_modifier_flags(TRAPS) const2836 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2837 jint access = access_flags().as_int();
2838
2839 // But check if it happens to be member class.
2840 InnerClassesIterator iter(this);
2841 for (; !iter.done(); iter.next()) {
2842 int ioff = iter.inner_class_info_index();
2843 // Inner class attribute can be zero, skip it.
2844 // Strange but true: JVM spec. allows null inner class refs.
2845 if (ioff == 0) continue;
2846
2847 // only look at classes that are already loaded
2848 // since we are looking for the flags for our self.
2849 Symbol* inner_name = constants()->klass_name_at(ioff);
2850 if (name() == inner_name) {
2851 // This is really a member class.
2852 access = iter.inner_access_flags();
2853 break;
2854 }
2855 }
2856 // Remember to strip ACC_SUPER bit
2857 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2858 }
2859
jvmti_class_status() const2860 jint InstanceKlass::jvmti_class_status() const {
2861 jint result = 0;
2862
2863 if (is_linked()) {
2864 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2865 }
2866
2867 if (is_initialized()) {
2868 assert(is_linked(), "Class status is not consistent");
2869 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2870 }
2871 if (is_in_error_state()) {
2872 result |= JVMTI_CLASS_STATUS_ERROR;
2873 }
2874 return result;
2875 }
2876
method_at_itable(Klass * holder,int index,TRAPS)2877 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2878 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2879 int method_table_offset_in_words = ioe->offset()/wordSize;
2880 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2881 / itableOffsetEntry::size();
2882
2883 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2884 // If the interface isn't implemented by the receiver class,
2885 // the VM should throw IncompatibleClassChangeError.
2886 if (cnt >= nof_interfaces) {
2887 ResourceMark rm(THREAD);
2888 stringStream ss;
2889 bool same_module = (module() == holder->module());
2890 ss.print("Receiver class %s does not implement "
2891 "the interface %s defining the method to be called "
2892 "(%s%s%s)",
2893 external_name(), holder->external_name(),
2894 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2895 (same_module) ? "" : "; ",
2896 (same_module) ? "" : holder->class_in_module_of_loader());
2897 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2898 }
2899
2900 Klass* ik = ioe->interface_klass();
2901 if (ik == holder) break;
2902 }
2903
2904 itableMethodEntry* ime = ioe->first_method_entry(this);
2905 Method* m = ime[index].method();
2906 if (m == NULL) {
2907 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2908 }
2909 return m;
2910 }
2911
2912
2913 #if INCLUDE_JVMTI
2914 // update default_methods for redefineclasses for methods that are
2915 // not yet in the vtable due to concurrent subclass define and superinterface
2916 // redefinition
2917 // Note: those in the vtable, should have been updated via adjust_method_entries
adjust_default_methods(InstanceKlass * holder,bool * trace_name_printed)2918 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2919 // search the default_methods for uses of either obsolete or EMCP methods
2920 if (default_methods() != NULL) {
2921 for (int index = 0; index < default_methods()->length(); index ++) {
2922 Method* old_method = default_methods()->at(index);
2923 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2924 continue; // skip uninteresting entries
2925 }
2926 assert(!old_method->is_deleted(), "default methods may not be deleted");
2927
2928 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2929
2930 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2931 assert(old_method != new_method, "sanity check");
2932
2933 default_methods()->at_put(index, new_method);
2934 if (log_is_enabled(Info, redefine, class, update)) {
2935 ResourceMark rm;
2936 if (!(*trace_name_printed)) {
2937 log_info(redefine, class, update)
2938 ("adjust: klassname=%s default methods from name=%s",
2939 external_name(), old_method->method_holder()->external_name());
2940 *trace_name_printed = true;
2941 }
2942 log_debug(redefine, class, update, vtables)
2943 ("default method update: %s(%s) ",
2944 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2945 }
2946 }
2947 }
2948 }
2949 #endif // INCLUDE_JVMTI
2950
2951 // On-stack replacement stuff
add_osr_nmethod(nmethod * n)2952 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2953 // only one compilation can be active
2954 {
2955 // This is a short non-blocking critical region, so the no safepoint check is ok.
2956 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2957 assert(n->is_osr_method(), "wrong kind of nmethod");
2958 n->set_osr_link(osr_nmethods_head());
2959 set_osr_nmethods_head(n);
2960 // Raise the highest osr level if necessary
2961 if (TieredCompilation) {
2962 Method* m = n->method();
2963 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2964 }
2965 }
2966
2967 // Get rid of the osr methods for the same bci that have lower levels.
2968 if (TieredCompilation) {
2969 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2970 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2971 if (inv != NULL && inv->is_in_use()) {
2972 inv->make_not_entrant();
2973 }
2974 }
2975 }
2976 }
2977
2978 // Remove osr nmethod from the list. Return true if found and removed.
remove_osr_nmethod(nmethod * n)2979 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2980 // This is a short non-blocking critical region, so the no safepoint check is ok.
2981 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2982 assert(n->is_osr_method(), "wrong kind of nmethod");
2983 nmethod* last = NULL;
2984 nmethod* cur = osr_nmethods_head();
2985 int max_level = CompLevel_none; // Find the max comp level excluding n
2986 Method* m = n->method();
2987 // Search for match
2988 bool found = false;
2989 while(cur != NULL && cur != n) {
2990 if (TieredCompilation && m == cur->method()) {
2991 // Find max level before n
2992 max_level = MAX2(max_level, cur->comp_level());
2993 }
2994 last = cur;
2995 cur = cur->osr_link();
2996 }
2997 nmethod* next = NULL;
2998 if (cur == n) {
2999 found = true;
3000 next = cur->osr_link();
3001 if (last == NULL) {
3002 // Remove first element
3003 set_osr_nmethods_head(next);
3004 } else {
3005 last->set_osr_link(next);
3006 }
3007 }
3008 n->set_osr_link(NULL);
3009 if (TieredCompilation) {
3010 cur = next;
3011 while (cur != NULL) {
3012 // Find max level after n
3013 if (m == cur->method()) {
3014 max_level = MAX2(max_level, cur->comp_level());
3015 }
3016 cur = cur->osr_link();
3017 }
3018 m->set_highest_osr_comp_level(max_level);
3019 }
3020 return found;
3021 }
3022
mark_osr_nmethods(const Method * m)3023 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3024 // This is a short non-blocking critical region, so the no safepoint check is ok.
3025 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3026 nmethod* osr = osr_nmethods_head();
3027 int found = 0;
3028 while (osr != NULL) {
3029 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3030 if (osr->method() == m) {
3031 osr->mark_for_deoptimization();
3032 found++;
3033 }
3034 osr = osr->osr_link();
3035 }
3036 return found;
3037 }
3038
lookup_osr_nmethod(const Method * m,int bci,int comp_level,bool match_level) const3039 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3040 // This is a short non-blocking critical region, so the no safepoint check is ok.
3041 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3042 nmethod* osr = osr_nmethods_head();
3043 nmethod* best = NULL;
3044 while (osr != NULL) {
3045 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3046 // There can be a time when a c1 osr method exists but we are waiting
3047 // for a c2 version. When c2 completes its osr nmethod we will trash
3048 // the c1 version and only be able to find the c2 version. However
3049 // while we overflow in the c1 code at back branches we don't want to
3050 // try and switch to the same code as we are already running
3051
3052 if (osr->method() == m &&
3053 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3054 if (match_level) {
3055 if (osr->comp_level() == comp_level) {
3056 // Found a match - return it.
3057 return osr;
3058 }
3059 } else {
3060 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3061 if (osr->comp_level() == CompLevel_highest_tier) {
3062 // Found the best possible - return it.
3063 return osr;
3064 }
3065 best = osr;
3066 }
3067 }
3068 }
3069 osr = osr->osr_link();
3070 }
3071 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3072 return best;
3073 }
3074 return NULL;
3075 }
3076
3077 // -----------------------------------------------------------------------------------------------------
3078 // Printing
3079
3080 #ifndef PRODUCT
3081
3082 #define BULLET " - "
3083
3084 static const char* state_names[] = {
3085 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3086 };
3087
print_vtable(intptr_t * start,int len,outputStream * st)3088 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3089 for (int i = 0; i < len; i++) {
3090 intptr_t e = start[i];
3091 st->print("%d : " INTPTR_FORMAT, i, e);
3092 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3093 st->print(" ");
3094 ((Metadata*)e)->print_value_on(st);
3095 }
3096 st->cr();
3097 }
3098 }
3099
print_vtable(vtableEntry * start,int len,outputStream * st)3100 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3101 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3102 }
3103
print_on(outputStream * st) const3104 void InstanceKlass::print_on(outputStream* st) const {
3105 assert(is_klass(), "must be klass");
3106 Klass::print_on(st);
3107
3108 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3109 st->print(BULLET"klass size: %d", size()); st->cr();
3110 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3111 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3112 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3113 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3114 st->print(BULLET"sub: ");
3115 Klass* sub = subklass();
3116 int n;
3117 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3118 if (n < MaxSubklassPrintSize) {
3119 sub->print_value_on(st);
3120 st->print(" ");
3121 }
3122 }
3123 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3124 st->cr();
3125
3126 if (is_interface()) {
3127 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3128 if (nof_implementors() == 1) {
3129 st->print_cr(BULLET"implementor: ");
3130 st->print(" ");
3131 implementor()->print_value_on(st);
3132 st->cr();
3133 }
3134 }
3135
3136 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3137 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3138 if (Verbose || WizardMode) {
3139 Array<Method*>* method_array = methods();
3140 for (int i = 0; i < method_array->length(); i++) {
3141 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3142 }
3143 }
3144 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3145 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3146 if (Verbose && default_methods() != NULL) {
3147 Array<Method*>* method_array = default_methods();
3148 for (int i = 0; i < method_array->length(); i++) {
3149 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3150 }
3151 }
3152 if (default_vtable_indices() != NULL) {
3153 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3154 }
3155 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3156 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3157 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3158 if (class_loader_data() != NULL) {
3159 st->print(BULLET"class loader data: ");
3160 class_loader_data()->print_value_on(st);
3161 st->cr();
3162 }
3163 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3164 if (source_file_name() != NULL) {
3165 st->print(BULLET"source file: ");
3166 source_file_name()->print_value_on(st);
3167 st->cr();
3168 }
3169 if (source_debug_extension() != NULL) {
3170 st->print(BULLET"source debug extension: ");
3171 st->print("%s", source_debug_extension());
3172 st->cr();
3173 }
3174 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3175 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3176 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3177 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3178 {
3179 bool have_pv = false;
3180 // previous versions are linked together through the InstanceKlass
3181 for (InstanceKlass* pv_node = previous_versions();
3182 pv_node != NULL;
3183 pv_node = pv_node->previous_versions()) {
3184 if (!have_pv)
3185 st->print(BULLET"previous version: ");
3186 have_pv = true;
3187 pv_node->constants()->print_value_on(st);
3188 }
3189 if (have_pv) st->cr();
3190 }
3191
3192 if (generic_signature() != NULL) {
3193 st->print(BULLET"generic signature: ");
3194 generic_signature()->print_value_on(st);
3195 st->cr();
3196 }
3197 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3198 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3199 if (java_mirror() != NULL) {
3200 st->print(BULLET"java mirror: ");
3201 java_mirror()->print_value_on(st);
3202 st->cr();
3203 } else {
3204 st->print_cr(BULLET"java mirror: NULL");
3205 }
3206 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3207 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3208 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3209 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3210 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3211 FieldPrinter print_static_field(st);
3212 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3213 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3214 FieldPrinter print_nonstatic_field(st);
3215 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3216 ik->do_nonstatic_fields(&print_nonstatic_field);
3217
3218 st->print(BULLET"non-static oop maps: ");
3219 OopMapBlock* map = start_of_nonstatic_oop_maps();
3220 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3221 while (map < end_map) {
3222 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3223 map++;
3224 }
3225 st->cr();
3226 }
3227
3228 #endif //PRODUCT
3229
print_value_on(outputStream * st) const3230 void InstanceKlass::print_value_on(outputStream* st) const {
3231 assert(is_klass(), "must be klass");
3232 if (Verbose || WizardMode) access_flags().print_on(st);
3233 name()->print_value_on(st);
3234 }
3235
3236 #ifndef PRODUCT
3237
do_field(fieldDescriptor * fd)3238 void FieldPrinter::do_field(fieldDescriptor* fd) {
3239 _st->print(BULLET);
3240 if (_obj == NULL) {
3241 fd->print_on(_st);
3242 _st->cr();
3243 } else {
3244 fd->print_on_for(_st, _obj);
3245 _st->cr();
3246 }
3247 }
3248
3249
oop_print_on(oop obj,outputStream * st)3250 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3251 Klass::oop_print_on(obj, st);
3252
3253 if (this == SystemDictionary::String_klass()) {
3254 typeArrayOop value = java_lang_String::value(obj);
3255 juint length = java_lang_String::length(obj);
3256 if (value != NULL &&
3257 value->is_typeArray() &&
3258 length <= (juint) value->length()) {
3259 st->print(BULLET"string: ");
3260 java_lang_String::print(obj, st);
3261 st->cr();
3262 if (!WizardMode) return; // that is enough
3263 }
3264 }
3265
3266 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3267 FieldPrinter print_field(st, obj);
3268 do_nonstatic_fields(&print_field);
3269
3270 if (this == SystemDictionary::Class_klass()) {
3271 st->print(BULLET"signature: ");
3272 java_lang_Class::print_signature(obj, st);
3273 st->cr();
3274 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3275 st->print(BULLET"fake entry for mirror: ");
3276 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3277 st->cr();
3278 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3279 st->print(BULLET"fake entry for array: ");
3280 Metadata::print_value_on_maybe_null(st, array_klass);
3281 st->cr();
3282 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3283 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3284 Klass* real_klass = java_lang_Class::as_Klass(obj);
3285 if (real_klass != NULL && real_klass->is_instance_klass()) {
3286 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3287 }
3288 } else if (this == SystemDictionary::MethodType_klass()) {
3289 st->print(BULLET"signature: ");
3290 java_lang_invoke_MethodType::print_signature(obj, st);
3291 st->cr();
3292 }
3293 }
3294
verify_itable_index(int i)3295 bool InstanceKlass::verify_itable_index(int i) {
3296 int method_count = klassItable::method_count_for_interface(this);
3297 assert(i >= 0 && i < method_count, "index out of bounds");
3298 return true;
3299 }
3300
3301 #endif //PRODUCT
3302
oop_print_value_on(oop obj,outputStream * st)3303 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3304 st->print("a ");
3305 name()->print_value_on(st);
3306 obj->print_address_on(st);
3307 if (this == SystemDictionary::String_klass()
3308 && java_lang_String::value(obj) != NULL) {
3309 ResourceMark rm;
3310 int len = java_lang_String::length(obj);
3311 int plen = (len < 24 ? len : 12);
3312 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3313 st->print(" = \"%s\"", str);
3314 if (len > plen)
3315 st->print("...[%d]", len);
3316 } else if (this == SystemDictionary::Class_klass()) {
3317 Klass* k = java_lang_Class::as_Klass(obj);
3318 st->print(" = ");
3319 if (k != NULL) {
3320 k->print_value_on(st);
3321 } else {
3322 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3323 st->print("%s", tname ? tname : "type?");
3324 }
3325 } else if (this == SystemDictionary::MethodType_klass()) {
3326 st->print(" = ");
3327 java_lang_invoke_MethodType::print_signature(obj, st);
3328 } else if (java_lang_boxing_object::is_instance(obj)) {
3329 st->print(" = ");
3330 java_lang_boxing_object::print(obj, st);
3331 } else if (this == SystemDictionary::LambdaForm_klass()) {
3332 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3333 if (vmentry != NULL) {
3334 st->print(" => ");
3335 vmentry->print_value_on(st);
3336 }
3337 } else if (this == SystemDictionary::MemberName_klass()) {
3338 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3339 if (vmtarget != NULL) {
3340 st->print(" = ");
3341 vmtarget->print_value_on(st);
3342 } else {
3343 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3344 st->print(".");
3345 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3346 }
3347 }
3348 }
3349
internal_name() const3350 const char* InstanceKlass::internal_name() const {
3351 return external_name();
3352 }
3353
print_class_load_logging(ClassLoaderData * loader_data,const char * module_name,const ClassFileStream * cfs) const3354 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3355 const char* module_name,
3356 const ClassFileStream* cfs) const {
3357 if (!log_is_enabled(Info, class, load)) {
3358 return;
3359 }
3360
3361 ResourceMark rm;
3362 LogMessage(class, load) msg;
3363 stringStream info_stream;
3364
3365 // Name and class hierarchy info
3366 info_stream.print("%s", external_name());
3367
3368 // Source
3369 if (cfs != NULL) {
3370 if (cfs->source() != NULL) {
3371 if (module_name != NULL) {
3372 if (ClassLoader::is_modules_image(cfs->source())) {
3373 info_stream.print(" source: jrt:/%s", module_name);
3374 } else {
3375 info_stream.print(" source: %s", cfs->source());
3376 }
3377 } else {
3378 info_stream.print(" source: %s", cfs->source());
3379 }
3380 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3381 Thread* THREAD = Thread::current();
3382 Klass* caller =
3383 THREAD->is_Java_thread()
3384 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3385 : NULL;
3386 // caller can be NULL, for example, during a JVMTI VM_Init hook
3387 if (caller != NULL) {
3388 info_stream.print(" source: instance of %s", caller->external_name());
3389 } else {
3390 // source is unknown
3391 }
3392 } else {
3393 oop class_loader = loader_data->class_loader();
3394 info_stream.print(" source: %s", class_loader->klass()->external_name());
3395 }
3396 } else {
3397 info_stream.print(" source: shared objects file");
3398 }
3399
3400 msg.info("%s", info_stream.as_string());
3401
3402 if (log_is_enabled(Debug, class, load)) {
3403 stringStream debug_stream;
3404
3405 // Class hierarchy info
3406 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3407 p2i(this), p2i(superklass()));
3408
3409 // Interfaces
3410 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3411 debug_stream.print(" interfaces:");
3412 int length = local_interfaces()->length();
3413 for (int i = 0; i < length; i++) {
3414 debug_stream.print(" " INTPTR_FORMAT,
3415 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3416 }
3417 }
3418
3419 // Class loader
3420 debug_stream.print(" loader: [");
3421 loader_data->print_value_on(&debug_stream);
3422 debug_stream.print("]");
3423
3424 // Classfile checksum
3425 if (cfs) {
3426 debug_stream.print(" bytes: %d checksum: %08x",
3427 cfs->length(),
3428 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3429 cfs->length()));
3430 }
3431
3432 msg.debug("%s", debug_stream.as_string());
3433 }
3434 }
3435
3436 #if INCLUDE_SERVICES
3437 // Size Statistics
collect_statistics(KlassSizeStats * sz) const3438 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3439 Klass::collect_statistics(sz);
3440
3441 sz->_inst_size = wordSize * size_helper();
3442 sz->_vtab_bytes = wordSize * vtable_length();
3443 sz->_itab_bytes = wordSize * itable_length();
3444 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3445
3446 int n = 0;
3447 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3448 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3449 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3450 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3451 n += (sz->_fields_bytes = sz->count_array(fields()));
3452 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3453 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3454 sz->_ro_bytes += n;
3455
3456 const ConstantPool* cp = constants();
3457 if (cp) {
3458 cp->collect_statistics(sz);
3459 }
3460
3461 const Annotations* anno = annotations();
3462 if (anno) {
3463 anno->collect_statistics(sz);
3464 }
3465
3466 const Array<Method*>* methods_array = methods();
3467 if (methods()) {
3468 for (int i = 0; i < methods_array->length(); i++) {
3469 Method* method = methods_array->at(i);
3470 if (method) {
3471 sz->_method_count ++;
3472 method->collect_statistics(sz);
3473 }
3474 }
3475 }
3476 }
3477 #endif // INCLUDE_SERVICES
3478
3479 // Verification
3480
3481 class VerifyFieldClosure: public BasicOopIterateClosure {
3482 protected:
do_oop_work(T * p)3483 template <class T> void do_oop_work(T* p) {
3484 oop obj = RawAccess<>::oop_load(p);
3485 if (!oopDesc::is_oop_or_null(obj)) {
3486 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3487 Universe::print_on(tty);
3488 guarantee(false, "boom");
3489 }
3490 }
3491 public:
do_oop(oop * p)3492 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
do_oop(narrowOop * p)3493 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3494 };
3495
verify_on(outputStream * st)3496 void InstanceKlass::verify_on(outputStream* st) {
3497 #ifndef PRODUCT
3498 // Avoid redundant verifies, this really should be in product.
3499 if (_verify_count == Universe::verify_count()) return;
3500 _verify_count = Universe::verify_count();
3501 #endif
3502
3503 // Verify Klass
3504 Klass::verify_on(st);
3505
3506 // Verify that klass is present in ClassLoaderData
3507 guarantee(class_loader_data()->contains_klass(this),
3508 "this class isn't found in class loader data");
3509
3510 // Verify vtables
3511 if (is_linked()) {
3512 // $$$ This used to be done only for m/s collections. Doing it
3513 // always seemed a valid generalization. (DLD -- 6/00)
3514 vtable().verify(st);
3515 }
3516
3517 // Verify first subklass
3518 if (subklass() != NULL) {
3519 guarantee(subklass()->is_klass(), "should be klass");
3520 }
3521
3522 // Verify siblings
3523 Klass* super = this->super();
3524 Klass* sib = next_sibling();
3525 if (sib != NULL) {
3526 if (sib == this) {
3527 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3528 }
3529
3530 guarantee(sib->is_klass(), "should be klass");
3531 guarantee(sib->super() == super, "siblings should have same superklass");
3532 }
3533
3534 // Verify local interfaces
3535 if (local_interfaces()) {
3536 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3537 for (int j = 0; j < local_interfaces->length(); j++) {
3538 InstanceKlass* e = local_interfaces->at(j);
3539 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3540 }
3541 }
3542
3543 // Verify transitive interfaces
3544 if (transitive_interfaces() != NULL) {
3545 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3546 for (int j = 0; j < transitive_interfaces->length(); j++) {
3547 InstanceKlass* e = transitive_interfaces->at(j);
3548 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3549 }
3550 }
3551
3552 // Verify methods
3553 if (methods() != NULL) {
3554 Array<Method*>* methods = this->methods();
3555 for (int j = 0; j < methods->length(); j++) {
3556 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3557 }
3558 for (int j = 0; j < methods->length() - 1; j++) {
3559 Method* m1 = methods->at(j);
3560 Method* m2 = methods->at(j + 1);
3561 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3562 }
3563 }
3564
3565 // Verify method ordering
3566 if (method_ordering() != NULL) {
3567 Array<int>* method_ordering = this->method_ordering();
3568 int length = method_ordering->length();
3569 if (JvmtiExport::can_maintain_original_method_order() ||
3570 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3571 guarantee(length == methods()->length(), "invalid method ordering length");
3572 jlong sum = 0;
3573 for (int j = 0; j < length; j++) {
3574 int original_index = method_ordering->at(j);
3575 guarantee(original_index >= 0, "invalid method ordering index");
3576 guarantee(original_index < length, "invalid method ordering index");
3577 sum += original_index;
3578 }
3579 // Verify sum of indices 0,1,...,length-1
3580 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3581 } else {
3582 guarantee(length == 0, "invalid method ordering length");
3583 }
3584 }
3585
3586 // Verify default methods
3587 if (default_methods() != NULL) {
3588 Array<Method*>* methods = this->default_methods();
3589 for (int j = 0; j < methods->length(); j++) {
3590 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3591 }
3592 for (int j = 0; j < methods->length() - 1; j++) {
3593 Method* m1 = methods->at(j);
3594 Method* m2 = methods->at(j + 1);
3595 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3596 }
3597 }
3598
3599 // Verify JNI static field identifiers
3600 if (jni_ids() != NULL) {
3601 jni_ids()->verify(this);
3602 }
3603
3604 // Verify other fields
3605 if (array_klasses() != NULL) {
3606 guarantee(array_klasses()->is_klass(), "should be klass");
3607 }
3608 if (constants() != NULL) {
3609 guarantee(constants()->is_constantPool(), "should be constant pool");
3610 }
3611 const Klass* anonymous_host = unsafe_anonymous_host();
3612 if (anonymous_host != NULL) {
3613 guarantee(anonymous_host->is_klass(), "should be klass");
3614 }
3615 }
3616
oop_verify_on(oop obj,outputStream * st)3617 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3618 Klass::oop_verify_on(obj, st);
3619 VerifyFieldClosure blk;
3620 obj->oop_iterate(&blk);
3621 }
3622
3623
3624 // JNIid class for jfieldIDs only
3625 // Note to reviewers:
3626 // These JNI functions are just moved over to column 1 and not changed
3627 // in the compressed oops workspace.
JNIid(Klass * holder,int offset,JNIid * next)3628 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3629 _holder = holder;
3630 _offset = offset;
3631 _next = next;
3632 debug_only(_is_static_field_id = false;)
3633 }
3634
3635
find(int offset)3636 JNIid* JNIid::find(int offset) {
3637 JNIid* current = this;
3638 while (current != NULL) {
3639 if (current->offset() == offset) return current;
3640 current = current->next();
3641 }
3642 return NULL;
3643 }
3644
deallocate(JNIid * current)3645 void JNIid::deallocate(JNIid* current) {
3646 while (current != NULL) {
3647 JNIid* next = current->next();
3648 delete current;
3649 current = next;
3650 }
3651 }
3652
3653
verify(Klass * holder)3654 void JNIid::verify(Klass* holder) {
3655 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3656 int end_field_offset;
3657 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3658
3659 JNIid* current = this;
3660 while (current != NULL) {
3661 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3662 #ifdef ASSERT
3663 int o = current->offset();
3664 if (current->is_static_field_id()) {
3665 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3666 }
3667 #endif
3668 current = current->next();
3669 }
3670 }
3671
set_init_state(ClassState state)3672 void InstanceKlass::set_init_state(ClassState state) {
3673 #ifdef ASSERT
3674 bool good_state = is_shared() ? (_init_state <= state)
3675 : (_init_state < state);
3676 assert(good_state || state == allocated, "illegal state transition");
3677 #endif
3678 _init_state = (u1)state;
3679 }
3680
3681 #if INCLUDE_JVMTI
3682
3683 // RedefineClasses() support for previous versions
3684
3685 // Globally, there is at least one previous version of a class to walk
3686 // during class unloading, which is saved because old methods in the class
3687 // are still running. Otherwise the previous version list is cleaned up.
3688 bool InstanceKlass::_has_previous_versions = false;
3689
3690 // Returns true if there are previous versions of a class for class
3691 // unloading only. Also resets the flag to false. purge_previous_version
3692 // will set the flag to true if there are any left, i.e., if there's any
3693 // work to do for next time. This is to avoid the expensive code cache
3694 // walk in CLDG::clean_deallocate_lists().
has_previous_versions_and_reset()3695 bool InstanceKlass::has_previous_versions_and_reset() {
3696 bool ret = _has_previous_versions;
3697 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3698 ret ? "true" : "false");
3699 _has_previous_versions = false;
3700 return ret;
3701 }
3702
3703 // Purge previous versions before adding new previous versions of the class and
3704 // during class unloading.
purge_previous_version_list()3705 void InstanceKlass::purge_previous_version_list() {
3706 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3707 assert(has_been_redefined(), "Should only be called for main class");
3708
3709 // Quick exit.
3710 if (previous_versions() == NULL) {
3711 return;
3712 }
3713
3714 // This klass has previous versions so see what we can cleanup
3715 // while it is safe to do so.
3716
3717 int deleted_count = 0; // leave debugging breadcrumbs
3718 int live_count = 0;
3719 ClassLoaderData* loader_data = class_loader_data();
3720 assert(loader_data != NULL, "should never be null");
3721
3722 ResourceMark rm;
3723 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3724
3725 // previous versions are linked together through the InstanceKlass
3726 InstanceKlass* pv_node = previous_versions();
3727 InstanceKlass* last = this;
3728 int version = 0;
3729
3730 // check the previous versions list
3731 for (; pv_node != NULL; ) {
3732
3733 ConstantPool* pvcp = pv_node->constants();
3734 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3735
3736 if (!pvcp->on_stack()) {
3737 // If the constant pool isn't on stack, none of the methods
3738 // are executing. Unlink this previous_version.
3739 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3740 // so will be deallocated during the next phase of class unloading.
3741 log_trace(redefine, class, iklass, purge)
3742 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3743 // For debugging purposes.
3744 pv_node->set_is_scratch_class();
3745 // Unlink from previous version list.
3746 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3747 InstanceKlass* next = pv_node->previous_versions();
3748 pv_node->link_previous_versions(NULL); // point next to NULL
3749 last->link_previous_versions(next);
3750 // Add to the deallocate list after unlinking
3751 loader_data->add_to_deallocate_list(pv_node);
3752 pv_node = next;
3753 deleted_count++;
3754 version++;
3755 continue;
3756 } else {
3757 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3758 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3759 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3760 live_count++;
3761 // found a previous version for next time we do class unloading
3762 _has_previous_versions = true;
3763 }
3764
3765 // At least one method is live in this previous version.
3766 // Reset dead EMCP methods not to get breakpoints.
3767 // All methods are deallocated when all of the methods for this class are no
3768 // longer running.
3769 Array<Method*>* method_refs = pv_node->methods();
3770 if (method_refs != NULL) {
3771 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3772 for (int j = 0; j < method_refs->length(); j++) {
3773 Method* method = method_refs->at(j);
3774
3775 if (!method->on_stack()) {
3776 // no breakpoints for non-running methods
3777 if (method->is_running_emcp()) {
3778 method->set_running_emcp(false);
3779 }
3780 } else {
3781 assert (method->is_obsolete() || method->is_running_emcp(),
3782 "emcp method cannot run after emcp bit is cleared");
3783 log_trace(redefine, class, iklass, purge)
3784 ("purge: %s(%s): prev method @%d in version @%d is alive",
3785 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3786 }
3787 }
3788 }
3789 // next previous version
3790 last = pv_node;
3791 pv_node = pv_node->previous_versions();
3792 version++;
3793 }
3794 log_trace(redefine, class, iklass, purge)
3795 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3796 }
3797
mark_newly_obsolete_methods(Array<Method * > * old_methods,int emcp_method_count)3798 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3799 int emcp_method_count) {
3800 int obsolete_method_count = old_methods->length() - emcp_method_count;
3801
3802 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3803 _previous_versions != NULL) {
3804 // We have a mix of obsolete and EMCP methods so we have to
3805 // clear out any matching EMCP method entries the hard way.
3806 int local_count = 0;
3807 for (int i = 0; i < old_methods->length(); i++) {
3808 Method* old_method = old_methods->at(i);
3809 if (old_method->is_obsolete()) {
3810 // only obsolete methods are interesting
3811 Symbol* m_name = old_method->name();
3812 Symbol* m_signature = old_method->signature();
3813
3814 // previous versions are linked together through the InstanceKlass
3815 int j = 0;
3816 for (InstanceKlass* prev_version = _previous_versions;
3817 prev_version != NULL;
3818 prev_version = prev_version->previous_versions(), j++) {
3819
3820 Array<Method*>* method_refs = prev_version->methods();
3821 for (int k = 0; k < method_refs->length(); k++) {
3822 Method* method = method_refs->at(k);
3823
3824 if (!method->is_obsolete() &&
3825 method->name() == m_name &&
3826 method->signature() == m_signature) {
3827 // The current RedefineClasses() call has made all EMCP
3828 // versions of this method obsolete so mark it as obsolete
3829 log_trace(redefine, class, iklass, add)
3830 ("%s(%s): flush obsolete method @%d in version @%d",
3831 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3832
3833 method->set_is_obsolete();
3834 break;
3835 }
3836 }
3837
3838 // The previous loop may not find a matching EMCP method, but
3839 // that doesn't mean that we can optimize and not go any
3840 // further back in the PreviousVersion generations. The EMCP
3841 // method for this generation could have already been made obsolete,
3842 // but there still may be an older EMCP method that has not
3843 // been made obsolete.
3844 }
3845
3846 if (++local_count >= obsolete_method_count) {
3847 // no more obsolete methods so bail out now
3848 break;
3849 }
3850 }
3851 }
3852 }
3853 }
3854
3855 // Save the scratch_class as the previous version if any of the methods are running.
3856 // The previous_versions are used to set breakpoints in EMCP methods and they are
3857 // also used to clean MethodData links to redefined methods that are no longer running.
add_previous_version(InstanceKlass * scratch_class,int emcp_method_count)3858 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3859 int emcp_method_count) {
3860 assert(Thread::current()->is_VM_thread(),
3861 "only VMThread can add previous versions");
3862
3863 ResourceMark rm;
3864 log_trace(redefine, class, iklass, add)
3865 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3866
3867 // Clean out old previous versions for this class
3868 purge_previous_version_list();
3869
3870 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3871 // a previous redefinition may be made obsolete by this redefinition.
3872 Array<Method*>* old_methods = scratch_class->methods();
3873 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3874
3875 // If the constant pool for this previous version of the class
3876 // is not marked as being on the stack, then none of the methods
3877 // in this previous version of the class are on the stack so
3878 // we don't need to add this as a previous version.
3879 ConstantPool* cp_ref = scratch_class->constants();
3880 if (!cp_ref->on_stack()) {
3881 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3882 // For debugging purposes.
3883 scratch_class->set_is_scratch_class();
3884 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3885 return;
3886 }
3887
3888 if (emcp_method_count != 0) {
3889 // At least one method is still running, check for EMCP methods
3890 for (int i = 0; i < old_methods->length(); i++) {
3891 Method* old_method = old_methods->at(i);
3892 if (!old_method->is_obsolete() && old_method->on_stack()) {
3893 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3894 // we can add breakpoints for it.
3895
3896 // We set the method->on_stack bit during safepoints for class redefinition
3897 // and use this bit to set the is_running_emcp bit.
3898 // After the safepoint, the on_stack bit is cleared and the running emcp
3899 // method may exit. If so, we would set a breakpoint in a method that
3900 // is never reached, but this won't be noticeable to the programmer.
3901 old_method->set_running_emcp(true);
3902 log_trace(redefine, class, iklass, add)
3903 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3904 } else if (!old_method->is_obsolete()) {
3905 log_trace(redefine, class, iklass, add)
3906 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3907 }
3908 }
3909 }
3910
3911 // Add previous version if any methods are still running.
3912 // Set has_previous_version flag for processing during class unloading.
3913 _has_previous_versions = true;
3914 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3915 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3916 scratch_class->link_previous_versions(previous_versions());
3917 link_previous_versions(scratch_class);
3918 } // end add_previous_version()
3919
3920 #endif // INCLUDE_JVMTI
3921
method_with_idnum(int idnum)3922 Method* InstanceKlass::method_with_idnum(int idnum) {
3923 Method* m = NULL;
3924 if (idnum < methods()->length()) {
3925 m = methods()->at(idnum);
3926 }
3927 if (m == NULL || m->method_idnum() != idnum) {
3928 for (int index = 0; index < methods()->length(); ++index) {
3929 m = methods()->at(index);
3930 if (m->method_idnum() == idnum) {
3931 return m;
3932 }
3933 }
3934 // None found, return null for the caller to handle.
3935 return NULL;
3936 }
3937 return m;
3938 }
3939
3940
method_with_orig_idnum(int idnum)3941 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3942 if (idnum >= methods()->length()) {
3943 return NULL;
3944 }
3945 Method* m = methods()->at(idnum);
3946 if (m != NULL && m->orig_method_idnum() == idnum) {
3947 return m;
3948 }
3949 // Obsolete method idnum does not match the original idnum
3950 for (int index = 0; index < methods()->length(); ++index) {
3951 m = methods()->at(index);
3952 if (m->orig_method_idnum() == idnum) {
3953 return m;
3954 }
3955 }
3956 // None found, return null for the caller to handle.
3957 return NULL;
3958 }
3959
3960
method_with_orig_idnum(int idnum,int version)3961 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3962 InstanceKlass* holder = get_klass_version(version);
3963 if (holder == NULL) {
3964 return NULL; // The version of klass is gone, no method is found
3965 }
3966 Method* method = holder->method_with_orig_idnum(idnum);
3967 return method;
3968 }
3969
3970 #if INCLUDE_JVMTI
get_cached_class_file()3971 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3972 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3973 // Ignore the archived class stream data
3974 return NULL;
3975 } else {
3976 return _cached_class_file;
3977 }
3978 }
3979
get_cached_class_file_len()3980 jint InstanceKlass::get_cached_class_file_len() {
3981 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3982 }
3983
get_cached_class_file_bytes()3984 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3985 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3986 }
3987
3988 #if INCLUDE_CDS
get_archived_class_data()3989 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3990 if (DumpSharedSpaces) {
3991 return _cached_class_file;
3992 } else {
3993 assert(this->is_shared(), "class should be shared");
3994 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3995 return _cached_class_file;
3996 } else {
3997 return NULL;
3998 }
3999 }
4000 }
4001 #endif
4002 #endif
4003