1 /*
2 * Copyright (c) 1997, 2020, 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/symbolTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "classfile/verifier.hpp"
38 #include "classfile/vmSymbols.hpp"
39 #include "code/dependencyContext.hpp"
40 #include "compiler/compileBroker.hpp"
41 #include "gc/shared/collectedHeap.inline.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "interpreter/rewriter.hpp"
44 #include "jvmtifiles/jvmti.h"
45 #include "logging/log.hpp"
46 #include "logging/logMessage.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.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 "memory/universe.hpp"
56 #include "oops/fieldStreams.inline.hpp"
57 #include "oops/constantPool.hpp"
58 #include "oops/instanceClassLoaderKlass.hpp"
59 #include "oops/instanceKlass.inline.hpp"
60 #include "oops/instanceMirrorKlass.hpp"
61 #include "oops/instanceOop.hpp"
62 #include "oops/klass.inline.hpp"
63 #include "oops/method.hpp"
64 #include "oops/oop.inline.hpp"
65 #include "oops/recordComponent.hpp"
66 #include "oops/symbol.hpp"
67 #include "prims/jvmtiExport.hpp"
68 #include "prims/jvmtiRedefineClasses.hpp"
69 #include "prims/jvmtiThreadState.hpp"
70 #include "prims/methodComparator.hpp"
71 #include "runtime/atomic.hpp"
72 #include "runtime/biasedLocking.hpp"
73 #include "runtime/fieldDescriptor.inline.hpp"
74 #include "runtime/handles.inline.hpp"
75 #include "runtime/javaCalls.hpp"
76 #include "runtime/mutexLocker.hpp"
77 #include "runtime/orderAccess.hpp"
78 #include "runtime/thread.inline.hpp"
79 #include "services/classLoadingService.hpp"
80 #include "services/threadService.hpp"
81 #include "utilities/dtrace.hpp"
82 #include "utilities/events.hpp"
83 #include "utilities/macros.hpp"
84 #include "utilities/stringUtils.hpp"
85 #ifdef COMPILER1
86 #include "c1/c1_Compiler.hpp"
87 #endif
88 #if INCLUDE_JFR
89 #include "jfr/jfrEvents.hpp"
90 #endif
91
92
93 #ifdef DTRACE_ENABLED
94
95
96 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
97 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
98 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
99 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
100 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
101 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
102 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
103 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
104 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
105 { \
106 char* data = NULL; \
107 int len = 0; \
108 Symbol* clss_name = name(); \
109 if (clss_name != NULL) { \
110 data = (char*)clss_name->bytes(); \
111 len = clss_name->utf8_length(); \
112 } \
113 HOTSPOT_CLASS_INITIALIZATION_##type( \
114 data, len, (void*)class_loader(), thread_type); \
115 }
116
117 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
118 { \
119 char* data = NULL; \
120 int len = 0; \
121 Symbol* clss_name = name(); \
122 if (clss_name != NULL) { \
123 data = (char*)clss_name->bytes(); \
124 len = clss_name->utf8_length(); \
125 } \
126 HOTSPOT_CLASS_INITIALIZATION_##type( \
127 data, len, (void*)class_loader(), thread_type, wait); \
128 }
129
130 #else // ndef DTRACE_ENABLED
131
132 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
133 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
134
135 #endif // ndef DTRACE_ENABLED
136
137 static inline bool is_class_loader(const Symbol* class_name,
138 const ClassFileParser& parser) {
139 assert(class_name != NULL, "invariant");
140
141 if (class_name == vmSymbols::java_lang_ClassLoader()) {
142 return true;
143 }
144
145 if (SystemDictionary::ClassLoader_klass_loaded()) {
146 const Klass* const super_klass = parser.super_klass();
147 if (super_klass != NULL) {
148 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
149 return true;
150 }
151 }
152 }
153 return false;
154 }
155
156 // called to verify that k is a member of this nest
157 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
158 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
159 if (log_is_enabled(Trace, class, nestmates)) {
160 ResourceMark rm(THREAD);
161 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
162 k->external_name(), this->external_name());
163 }
164 return false;
165 }
166
167 if (log_is_enabled(Trace, class, nestmates)) {
168 ResourceMark rm(THREAD);
169 log_trace(class, nestmates)("Checking nest membership of %s in %s",
170 k->external_name(), this->external_name());
171 }
172
173 // Check for a resolved cp entry , else fall back to a name check.
174 // We don't want to resolve any class other than the one being checked.
175 for (int i = 0; i < _nest_members->length(); i++) {
176 int cp_index = _nest_members->at(i);
177 if (_constants->tag_at(cp_index).is_klass()) {
178 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
179 if (k2 == k) {
180 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
181 return true;
182 }
183 }
184 else {
185 Symbol* name = _constants->klass_name_at(cp_index);
186 if (name == k->name()) {
187 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
188
189 // Names match so check actual klass - this may trigger class loading if
190 // it doesn't match (though that should be impossible). But to be safe we
191 // have to check for a compiler thread executing here.
192 if (!THREAD->can_call_java() && !_constants->tag_at(cp_index).is_klass()) {
193 log_trace(class, nestmates)("- validation required resolution in an unsuitable thread");
194 return false;
195 }
196
197 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
198 if (k2 == k) {
199 log_trace(class, nestmates)("- class is listed as a nest member");
200 return true;
201 }
202 else {
203 // same name but different klass!
204 log_trace(class, nestmates)(" - klass comparison failed!");
205 // can't have two names the same, so we're done
206 return false;
207 }
208 }
209 }
210 }
211 log_trace(class, nestmates)("- class is NOT a nest member!");
212 return false;
213 }
214
215 // Return nest-host class, resolving, validating and saving it if needed.
216 // In cases where this is called from a thread that can not do classloading
217 // (such as a native JIT thread) then we simply return NULL, which in turn
218 // causes the access check to return false. Such code will retry the access
219 // from a more suitable environment later.
220 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
221 InstanceKlass* nest_host_k = _nest_host;
222 if (nest_host_k == NULL) {
223 // need to resolve and save our nest-host class. This could be attempted
224 // concurrently but as the result is idempotent and we don't use the class
225 // then we do not need any synchronization beyond what is implicitly used
226 // during class loading.
227 if (_nest_host_index != 0) { // we have a real nest_host
228 // Before trying to resolve check if we're in a suitable context
229 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
230 if (log_is_enabled(Trace, class, nestmates)) {
231 ResourceMark rm(THREAD);
232 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
233 this->external_name());
234 }
235 return NULL;
236 }
237
238 if (log_is_enabled(Trace, class, nestmates)) {
239 ResourceMark rm(THREAD);
240 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
241 this->external_name(),
242 _constants->klass_name_at(_nest_host_index)->as_C_string());
243 }
244
245 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
246 if (HAS_PENDING_EXCEPTION) {
247 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
248 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
249 // throw a new CDNFE with the original as its cause, and a clear msg
250 ResourceMark rm(THREAD);
251 char buf[200];
252 CLEAR_PENDING_EXCEPTION;
253 jio_snprintf(buf, sizeof(buf),
254 "Unable to load nest-host class (%s) of %s",
255 _constants->klass_name_at(_nest_host_index)->as_C_string(),
256 this->external_name());
257 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
258 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
259 }
260 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
261 return NULL;
262 }
263
264 // A valid nest-host is an instance class in the current package that lists this
265 // class as a nest member. If any of these conditions are not met we post the
266 // requested exception type (if any) and return NULL
267
268 const char* error = NULL;
269
270 // JVMS 5.4.4 indicates package check comes first
271 if (is_same_class_package(k)) {
272
273 // Now check actual membership. We can't be a member if our "host" is
274 // not an instance class.
275 if (k->is_instance_klass()) {
276 nest_host_k = InstanceKlass::cast(k);
277
278 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
279 if (is_member) {
280 // save resolved nest-host value
281 _nest_host = nest_host_k;
282
283 if (log_is_enabled(Trace, class, nestmates)) {
284 ResourceMark rm(THREAD);
285 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
286 this->external_name(), k->external_name());
287 }
288 return nest_host_k;
289 }
290 }
291 error = "current type is not listed as a nest member";
292 } else {
293 error = "types are in different packages";
294 }
295
296 if (log_is_enabled(Trace, class, nestmates)) {
297 ResourceMark rm(THREAD);
298 log_trace(class, nestmates)
299 ("Type %s (loader: %s) is not a nest member of "
300 "resolved type %s (loader: %s): %s",
301 this->external_name(),
302 this->class_loader_data()->loader_name_and_id(),
303 k->external_name(),
304 k->class_loader_data()->loader_name_and_id(),
305 error);
306 }
307
308 if (validationException != NULL && THREAD->can_call_java()) {
309 ResourceMark rm(THREAD);
310 Exceptions::fthrow(THREAD_AND_LOCATION,
311 validationException,
312 "Type %s (loader: %s) is not a nest member of %s (loader: %s): %s",
313 this->external_name(),
314 this->class_loader_data()->loader_name_and_id(),
315 k->external_name(),
316 k->class_loader_data()->loader_name_and_id(),
317 error
318 );
319 }
320 return NULL;
321 } else {
322 if (log_is_enabled(Trace, class, nestmates)) {
323 ResourceMark rm(THREAD);
324 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
325 this->external_name());
326 }
327 // save resolved nest-host value
328 return (_nest_host = this);
329 }
330 }
331 return nest_host_k;
332 }
333
334 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
335 // or we are k's nest_host - all of which is covered by comparing the two
336 // resolved_nest_hosts
337 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
338
339 assert(this != k, "this should be handled by higher-level code");
340
341 // Per JVMS 5.4.4 we first resolve and validate the current class, then
342 // the target class k. Resolution exceptions will be passed on by upper
343 // layers. IncompatibleClassChangeErrors from membership validation failures
344 // will also be passed through.
345
346 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
347 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
348 if (cur_host == NULL) {
349 return false;
350 }
351
352 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
353 if (k_nest_host == NULL) {
354 return false;
355 }
356
357 bool access = (cur_host == k_nest_host);
358
359 if (log_is_enabled(Trace, class, nestmates)) {
360 ResourceMark rm(THREAD);
361 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
362 this->external_name(),
363 access ? "" : "NOT ",
364 k->external_name());
365 }
366
367 return access;
368 }
369
370 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
371 const int size = InstanceKlass::size(parser.vtable_size(),
372 parser.itable_size(),
373 nonstatic_oop_map_size(parser.total_oop_map_count()),
374 parser.is_interface(),
375 parser.is_unsafe_anonymous(),
376 should_store_fingerprint(parser.is_unsafe_anonymous()));
377
378 const Symbol* const class_name = parser.class_name();
379 assert(class_name != NULL, "invariant");
380 ClassLoaderData* loader_data = parser.loader_data();
381 assert(loader_data != NULL, "invariant");
382
383 InstanceKlass* ik;
384
385 // Allocation
386 if (REF_NONE == parser.reference_type()) {
387 if (class_name == vmSymbols::java_lang_Class()) {
388 // mirror
389 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
390 }
391 else if (is_class_loader(class_name, parser)) {
392 // class loader
393 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
394 } else {
395 // normal
396 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
397 }
398 } else {
399 // reference
400 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
401 }
402
403 // Check for pending exception before adding to the loader data and incrementing
404 // class count. Can get OOM here.
405 if (HAS_PENDING_EXCEPTION) {
406 return NULL;
407 }
408
409 return ik;
410 }
411
412
413 // copy method ordering from resource area to Metaspace
414 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
415 if (m != NULL) {
416 // allocate a new array and copy contents (memcpy?)
417 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
418 for (int i = 0; i < m->length(); i++) {
419 _method_ordering->at_put(i, m->at(i));
420 }
421 } else {
422 _method_ordering = Universe::the_empty_int_array();
423 }
424 }
425
426 // create a new array of vtable_indices for default methods
427 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
428 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
429 assert(default_vtable_indices() == NULL, "only create once");
430 set_default_vtable_indices(vtable_indices);
431 return vtable_indices;
432 }
433
434 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
435 Klass(id),
436 _nest_members(NULL),
437 _nest_host_index(0),
438 _nest_host(NULL),
439 _record_components(NULL),
440 _static_field_size(parser.static_field_size()),
441 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
442 _itable_len(parser.itable_size()),
443 _init_thread(NULL),
444 _init_state(allocated),
445 _reference_type(parser.reference_type())
446 {
447 set_vtable_length(parser.vtable_size());
448 set_kind(kind);
449 set_access_flags(parser.access_flags());
450 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
451 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
452 false));
453
454 assert(NULL == _methods, "underlying memory not zeroed?");
455 assert(is_instance_klass(), "is layout incorrect?");
456 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
457
458 if (Arguments::is_dumping_archive()) {
459 SystemDictionaryShared::init_dumptime_info(this);
460 }
461
462 // Set biased locking bit for all instances of this class; it will be
463 // cleared if revocation occurs too often for this type
464 if (UseBiasedLocking && BiasedLocking::enabled()) {
465 set_prototype_header(markWord::biased_locking_prototype());
466 }
467 }
468
469 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
470 Array<Method*>* methods) {
471 if (methods != NULL && methods != Universe::the_empty_method_array() &&
472 !methods->is_shared()) {
473 for (int i = 0; i < methods->length(); i++) {
474 Method* method = methods->at(i);
475 if (method == NULL) continue; // maybe null if error processing
476 // Only want to delete methods that are not executing for RedefineClasses.
477 // The previous version will point to them so they're not totally dangling
478 assert (!method->on_stack(), "shouldn't be called with methods on stack");
479 MetadataFactory::free_metadata(loader_data, method);
480 }
481 MetadataFactory::free_array<Method*>(loader_data, methods);
482 }
483 }
484
485 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
486 const Klass* super_klass,
487 Array<InstanceKlass*>* local_interfaces,
488 Array<InstanceKlass*>* transitive_interfaces) {
489 // Only deallocate transitive interfaces if not empty, same as super class
490 // or same as local interfaces. See code in parseClassFile.
491 Array<InstanceKlass*>* ti = transitive_interfaces;
492 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
493 // check that the interfaces don't come from super class
494 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
495 InstanceKlass::cast(super_klass)->transitive_interfaces();
496 if (ti != sti && ti != NULL && !ti->is_shared()) {
497 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
498 }
499 }
500
501 // local interfaces can be empty
502 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
503 local_interfaces != NULL && !local_interfaces->is_shared()) {
504 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
505 }
506 }
507
508 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
509 Array<RecordComponent*>* record_components) {
510 if (record_components != NULL && !record_components->is_shared()) {
511 for (int i = 0; i < record_components->length(); i++) {
512 RecordComponent* record_component = record_components->at(i);
513 MetadataFactory::free_metadata(loader_data, record_component);
514 }
515 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
516 }
517 }
518
519 // This function deallocates the metadata and C heap pointers that the
520 // InstanceKlass points to.
521 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
522
523 // Orphan the mirror first, CMS thinks it's still live.
524 if (java_mirror() != NULL) {
525 java_lang_Class::set_klass(java_mirror(), NULL);
526 }
527
528 // Also remove mirror from handles
529 loader_data->remove_handle(_java_mirror);
530
531 // Need to take this class off the class loader data list.
532 loader_data->remove_class(this);
533
534 // The array_klass for this class is created later, after error handling.
535 // For class redefinition, we keep the original class so this scratch class
536 // doesn't have an array class. Either way, assert that there is nothing
537 // to deallocate.
538 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
539
540 // Release C heap allocated data that this might point to, which includes
541 // reference counting symbol names.
542 release_C_heap_structures();
543
544 deallocate_methods(loader_data, methods());
545 set_methods(NULL);
546
547 deallocate_record_components(loader_data, record_components());
548 set_record_components(NULL);
549
550 if (method_ordering() != NULL &&
551 method_ordering() != Universe::the_empty_int_array() &&
552 !method_ordering()->is_shared()) {
553 MetadataFactory::free_array<int>(loader_data, method_ordering());
554 }
555 set_method_ordering(NULL);
556
557 // default methods can be empty
558 if (default_methods() != NULL &&
559 default_methods() != Universe::the_empty_method_array() &&
560 !default_methods()->is_shared()) {
561 MetadataFactory::free_array<Method*>(loader_data, default_methods());
562 }
563 // Do NOT deallocate the default methods, they are owned by superinterfaces.
564 set_default_methods(NULL);
565
566 // default methods vtable indices can be empty
567 if (default_vtable_indices() != NULL &&
568 !default_vtable_indices()->is_shared()) {
569 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
570 }
571 set_default_vtable_indices(NULL);
572
573
574 // This array is in Klass, but remove it with the InstanceKlass since
575 // this place would be the only caller and it can share memory with transitive
576 // interfaces.
577 if (secondary_supers() != NULL &&
578 secondary_supers() != Universe::the_empty_klass_array() &&
579 // see comments in compute_secondary_supers about the following cast
580 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
581 !secondary_supers()->is_shared()) {
582 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
583 }
584 set_secondary_supers(NULL);
585
586 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
587 set_transitive_interfaces(NULL);
588 set_local_interfaces(NULL);
589
590 if (fields() != NULL && !fields()->is_shared()) {
591 MetadataFactory::free_array<jushort>(loader_data, fields());
592 }
593 set_fields(NULL, 0);
594
595 // If a method from a redefined class is using this constant pool, don't
596 // delete it, yet. The new class's previous version will point to this.
597 if (constants() != NULL) {
598 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
599 if (!constants()->is_shared()) {
600 MetadataFactory::free_metadata(loader_data, constants());
601 }
602 // Delete any cached resolution errors for the constant pool
603 SystemDictionary::delete_resolution_error(constants());
604
605 set_constants(NULL);
606 }
607
608 if (inner_classes() != NULL &&
609 inner_classes() != Universe::the_empty_short_array() &&
610 !inner_classes()->is_shared()) {
611 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
612 }
613 set_inner_classes(NULL);
614
615 if (nest_members() != NULL &&
616 nest_members() != Universe::the_empty_short_array() &&
617 !nest_members()->is_shared()) {
618 MetadataFactory::free_array<jushort>(loader_data, nest_members());
619 }
620 set_nest_members(NULL);
621
622 // We should deallocate the Annotations instance if it's not in shared spaces.
623 if (annotations() != NULL && !annotations()->is_shared()) {
624 MetadataFactory::free_metadata(loader_data, annotations());
625 }
626 set_annotations(NULL);
627
628 if (Arguments::is_dumping_archive()) {
629 SystemDictionaryShared::remove_dumptime_info(this);
630 }
631 }
632
633 bool InstanceKlass::should_be_initialized() const {
634 return !is_initialized();
635 }
636
637 klassItable InstanceKlass::itable() const {
638 return klassItable(const_cast<InstanceKlass*>(this));
639 }
640
641 void InstanceKlass::eager_initialize(Thread *thread) {
642 if (!EagerInitialization) return;
643
644 if (this->is_not_initialized()) {
645 // abort if the the class has a class initializer
646 if (this->class_initializer() != NULL) return;
647
648 // abort if it is java.lang.Object (initialization is handled in genesis)
649 Klass* super_klass = super();
650 if (super_klass == NULL) return;
651
652 // abort if the super class should be initialized
653 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
654
655 // call body to expose the this pointer
656 eager_initialize_impl();
657 }
658 }
659
660 // JVMTI spec thinks there are signers and protection domain in the
661 // instanceKlass. These accessors pretend these fields are there.
662 // The hprof specification also thinks these fields are in InstanceKlass.
663 oop InstanceKlass::protection_domain() const {
664 // return the protection_domain from the mirror
665 return java_lang_Class::protection_domain(java_mirror());
666 }
667
668 // To remove these from requires an incompatible change and CCC request.
669 objArrayOop InstanceKlass::signers() const {
670 // return the signers from the mirror
671 return java_lang_Class::signers(java_mirror());
672 }
673
674 oop InstanceKlass::init_lock() const {
675 // return the init lock from the mirror
676 oop lock = java_lang_Class::init_lock(java_mirror());
677 // Prevent reordering with any access of initialization state
678 OrderAccess::loadload();
679 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
680 "only fully initialized state can have a null lock");
681 return lock;
682 }
683
684 // Set the initialization lock to null so the object can be GC'ed. Any racing
685 // threads to get this lock will see a null lock and will not lock.
686 // That's okay because they all check for initialized state after getting
687 // the lock and return.
688 void InstanceKlass::fence_and_clear_init_lock() {
689 // make sure previous stores are all done, notably the init_state.
690 OrderAccess::storestore();
691 java_lang_Class::set_init_lock(java_mirror(), NULL);
692 assert(!is_not_initialized(), "class must be initialized now");
693 }
694
695 void InstanceKlass::eager_initialize_impl() {
696 EXCEPTION_MARK;
697 HandleMark hm(THREAD);
698 Handle h_init_lock(THREAD, init_lock());
699 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
700
701 // abort if someone beat us to the initialization
702 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
703
704 ClassState old_state = init_state();
705 link_class_impl(THREAD);
706 if (HAS_PENDING_EXCEPTION) {
707 CLEAR_PENDING_EXCEPTION;
708 // Abort if linking the class throws an exception.
709
710 // Use a test to avoid redundantly resetting the state if there's
711 // no change. Set_init_state() asserts that state changes make
712 // progress, whereas here we might just be spinning in place.
713 if (old_state != _init_state)
714 set_init_state(old_state);
715 } else {
716 // linking successfull, mark class as initialized
717 set_init_state(fully_initialized);
718 fence_and_clear_init_lock();
719 // trace
720 if (log_is_enabled(Info, class, init)) {
721 ResourceMark rm(THREAD);
722 log_info(class, init)("[Initialized %s without side effects]", external_name());
723 }
724 }
725 }
726
727
728 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
729 // process. The step comments refers to the procedure described in that section.
730 // Note: implementation moved to static method to expose the this pointer.
731 void InstanceKlass::initialize(TRAPS) {
732 if (this->should_be_initialized()) {
733 initialize_impl(CHECK);
734 // Note: at this point the class may be initialized
735 // OR it may be in the state of being initialized
736 // in case of recursive initialization!
737 } else {
738 assert(is_initialized(), "sanity check");
739 }
740 }
741
742
743 bool InstanceKlass::verify_code(TRAPS) {
744 // 1) Verify the bytecodes
745 return Verifier::verify(this, should_verify_class(), THREAD);
746 }
747
748 void InstanceKlass::link_class(TRAPS) {
749 assert(is_loaded(), "must be loaded");
750 if (!is_linked()) {
751 link_class_impl(CHECK);
752 }
753 }
754
755 // Called to verify that a class can link during initialization, without
756 // throwing a VerifyError.
757 bool InstanceKlass::link_class_or_fail(TRAPS) {
758 assert(is_loaded(), "must be loaded");
759 if (!is_linked()) {
760 link_class_impl(CHECK_false);
761 }
762 return is_linked();
763 }
764
765 bool InstanceKlass::link_class_impl(TRAPS) {
766 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
767 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
768 // the class has failed verification. Throwing the NoClassDefFoundError here is just
769 // a convenient way to stop repeat attempts to verify the same (bad) class.
770 //
771 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
772 // if we are executing Java code. This is not a problem for CDS dumping phase since
773 // it doesn't execute any Java code.
774 ResourceMark rm(THREAD);
775 Exceptions::fthrow(THREAD_AND_LOCATION,
776 vmSymbols::java_lang_NoClassDefFoundError(),
777 "Class %s, or one of its supertypes, failed class initialization",
778 external_name());
779 return false;
780 }
781 // return if already verified
782 if (is_linked()) {
783 return true;
784 }
785
786 // Timing
787 // timer handles recursion
788 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
789 JavaThread* jt = (JavaThread*)THREAD;
790
791 // link super class before linking this class
792 Klass* super_klass = super();
793 if (super_klass != NULL) {
794 if (super_klass->is_interface()) { // check if super class is an interface
795 ResourceMark rm(THREAD);
796 Exceptions::fthrow(
797 THREAD_AND_LOCATION,
798 vmSymbols::java_lang_IncompatibleClassChangeError(),
799 "class %s has interface %s as super class",
800 external_name(),
801 super_klass->external_name()
802 );
803 return false;
804 }
805
806 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
807 ik_super->link_class_impl(CHECK_false);
808 }
809
810 // link all interfaces implemented by this class before linking this class
811 Array<InstanceKlass*>* interfaces = local_interfaces();
812 int num_interfaces = interfaces->length();
813 for (int index = 0; index < num_interfaces; index++) {
814 InstanceKlass* interk = interfaces->at(index);
815 interk->link_class_impl(CHECK_false);
816 }
817
818 // in case the class is linked in the process of linking its superclasses
819 if (is_linked()) {
820 return true;
821 }
822
823 // trace only the link time for this klass that includes
824 // the verification time
825 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
826 ClassLoader::perf_class_link_selftime(),
827 ClassLoader::perf_classes_linked(),
828 jt->get_thread_stat()->perf_recursion_counts_addr(),
829 jt->get_thread_stat()->perf_timers_addr(),
830 PerfClassTraceTime::CLASS_LINK);
831
832 // verification & rewriting
833 {
834 HandleMark hm(THREAD);
835 Handle h_init_lock(THREAD, init_lock());
836 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
837 // rewritten will have been set if loader constraint error found
838 // on an earlier link attempt
839 // don't verify or rewrite if already rewritten
840 //
841
842 if (!is_linked()) {
843 if (!is_rewritten()) {
844 {
845 bool verify_ok = verify_code(THREAD);
846 if (!verify_ok) {
847 return false;
848 }
849 }
850
851 // Just in case a side-effect of verify linked this class already
852 // (which can sometimes happen since the verifier loads classes
853 // using custom class loaders, which are free to initialize things)
854 if (is_linked()) {
855 return true;
856 }
857
858 // also sets rewritten
859 rewrite_class(CHECK_false);
860 } else if (is_shared()) {
861 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
862 }
863
864 // relocate jsrs and link methods after they are all rewritten
865 link_methods(CHECK_false);
866
867 // Initialize the vtable and interface table after
868 // methods have been rewritten since rewrite may
869 // fabricate new Method*s.
870 // also does loader constraint checking
871 //
872 // initialize_vtable and initialize_itable need to be rerun for
873 // a shared class if the class is not loaded by the NULL classloader.
874 ClassLoaderData * loader_data = class_loader_data();
875 if (!(is_shared() &&
876 loader_data->is_the_null_class_loader_data())) {
877 vtable().initialize_vtable(true, CHECK_false);
878 itable().initialize_itable(true, CHECK_false);
879 }
880 #ifdef ASSERT
881 else {
882 vtable().verify(tty, true);
883 // In case itable verification is ever added.
884 // itable().verify(tty, true);
885 }
886 #endif
887 set_init_state(linked);
888 if (JvmtiExport::should_post_class_prepare()) {
889 Thread *thread = THREAD;
890 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
891 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
892 }
893 }
894 }
895 return true;
896 }
897
898 // Rewrite the byte codes of all of the methods of a class.
899 // The rewriter must be called exactly once. Rewriting must happen after
900 // verification but before the first method of the class is executed.
901 void InstanceKlass::rewrite_class(TRAPS) {
902 assert(is_loaded(), "must be loaded");
903 if (is_rewritten()) {
904 assert(is_shared(), "rewriting an unshared class?");
905 return;
906 }
907 Rewriter::rewrite(this, CHECK);
908 set_rewritten();
909 }
910
911 // Now relocate and link method entry points after class is rewritten.
912 // This is outside is_rewritten flag. In case of an exception, it can be
913 // executed more than once.
914 void InstanceKlass::link_methods(TRAPS) {
915 int len = methods()->length();
916 for (int i = len-1; i >= 0; i--) {
917 methodHandle m(THREAD, methods()->at(i));
918
919 // Set up method entry points for compiler and interpreter .
920 m->link_method(m, CHECK);
921 }
922 }
923
924 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
925 void InstanceKlass::initialize_super_interfaces(TRAPS) {
926 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
927 for (int i = 0; i < local_interfaces()->length(); ++i) {
928 InstanceKlass* ik = local_interfaces()->at(i);
929
930 // Initialization is depth first search ie. we start with top of the inheritance tree
931 // has_nonstatic_concrete_methods drives searching superinterfaces since it
932 // means has_nonstatic_concrete_methods in its superinterface hierarchy
933 if (ik->has_nonstatic_concrete_methods()) {
934 ik->initialize_super_interfaces(CHECK);
935 }
936
937 // Only initialize() interfaces that "declare" concrete methods.
938 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
939 ik->initialize(CHECK);
940 }
941 }
942 }
943
944 void InstanceKlass::initialize_impl(TRAPS) {
945 HandleMark hm(THREAD);
946
947 // Make sure klass is linked (verified) before initialization
948 // A class could already be verified, since it has been reflected upon.
949 link_class(CHECK);
950
951 DTRACE_CLASSINIT_PROBE(required, -1);
952
953 bool wait = false;
954
955 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
956 JavaThread* jt = (JavaThread*)THREAD;
957
958 // refer to the JVM book page 47 for description of steps
959 // Step 1
960 {
961 Handle h_init_lock(THREAD, init_lock());
962 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
963
964 // Step 2
965 // If we were to use wait() instead of waitInterruptibly() then
966 // we might end up throwing IE from link/symbol resolution sites
967 // that aren't expected to throw. This would wreak havoc. See 6320309.
968 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
969 wait = true;
970 jt->set_class_to_be_initialized(this);
971 ol.wait_uninterruptibly(jt);
972 jt->set_class_to_be_initialized(NULL);
973 }
974
975 // Step 3
976 if (is_being_initialized() && is_reentrant_initialization(jt)) {
977 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
978 return;
979 }
980
981 // Step 4
982 if (is_initialized()) {
983 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
984 return;
985 }
986
987 // Step 5
988 if (is_in_error_state()) {
989 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
990 ResourceMark rm(THREAD);
991 const char* desc = "Could not initialize class ";
992 const char* className = external_name();
993 size_t msglen = strlen(desc) + strlen(className) + 1;
994 char* message = NEW_RESOURCE_ARRAY(char, msglen);
995 if (NULL == message) {
996 // Out of memory: can't create detailed error message
997 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
998 } else {
999 jio_snprintf(message, msglen, "%s%s", desc, className);
1000 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
1001 }
1002 }
1003
1004 // Step 6
1005 set_init_state(being_initialized);
1006 set_init_thread(jt);
1007 }
1008
1009 // Step 7
1010 // Next, if C is a class rather than an interface, initialize it's super class and super
1011 // interfaces.
1012 if (!is_interface()) {
1013 Klass* super_klass = super();
1014 if (super_klass != NULL && super_klass->should_be_initialized()) {
1015 super_klass->initialize(THREAD);
1016 }
1017 // If C implements any interface that declares a non-static, concrete method,
1018 // the initialization of C triggers initialization of its super interfaces.
1019 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1020 // having a superinterface that declares, non-static, concrete methods
1021 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1022 initialize_super_interfaces(THREAD);
1023 }
1024
1025 // If any exceptions, complete abruptly, throwing the same exception as above.
1026 if (HAS_PENDING_EXCEPTION) {
1027 Handle e(THREAD, PENDING_EXCEPTION);
1028 CLEAR_PENDING_EXCEPTION;
1029 {
1030 EXCEPTION_MARK;
1031 // Locks object, set state, and notify all waiting threads
1032 set_initialization_state_and_notify(initialization_error, THREAD);
1033 CLEAR_PENDING_EXCEPTION;
1034 }
1035 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1036 THROW_OOP(e());
1037 }
1038 }
1039
1040
1041 // Look for aot compiled methods for this klass, including class initializer.
1042 AOTLoader::load_for_klass(this, THREAD);
1043
1044 // Step 8
1045 {
1046 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1047 // Timer includes any side effects of class initialization (resolution,
1048 // etc), but not recursive entry into call_class_initializer().
1049 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1050 ClassLoader::perf_class_init_selftime(),
1051 ClassLoader::perf_classes_inited(),
1052 jt->get_thread_stat()->perf_recursion_counts_addr(),
1053 jt->get_thread_stat()->perf_timers_addr(),
1054 PerfClassTraceTime::CLASS_CLINIT);
1055 call_class_initializer(THREAD);
1056 }
1057
1058 // Step 9
1059 if (!HAS_PENDING_EXCEPTION) {
1060 set_initialization_state_and_notify(fully_initialized, CHECK);
1061 {
1062 debug_only(vtable().verify(tty, true);)
1063 }
1064 }
1065 else {
1066 // Step 10 and 11
1067 Handle e(THREAD, PENDING_EXCEPTION);
1068 CLEAR_PENDING_EXCEPTION;
1069 // JVMTI has already reported the pending exception
1070 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1071 JvmtiExport::clear_detected_exception(jt);
1072 {
1073 EXCEPTION_MARK;
1074 set_initialization_state_and_notify(initialization_error, THREAD);
1075 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1076 // JVMTI has already reported the pending exception
1077 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1078 JvmtiExport::clear_detected_exception(jt);
1079 }
1080 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1081 if (e->is_a(SystemDictionary::Error_klass())) {
1082 THROW_OOP(e());
1083 } else {
1084 JavaCallArguments args(e);
1085 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1086 vmSymbols::throwable_void_signature(),
1087 &args);
1088 }
1089 }
1090 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1091 }
1092
1093
1094 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1095 Handle h_init_lock(THREAD, init_lock());
1096 if (h_init_lock() != NULL) {
1097 ObjectLocker ol(h_init_lock, THREAD);
1098 set_init_thread(NULL); // reset _init_thread before changing _init_state
1099 set_init_state(state);
1100 fence_and_clear_init_lock();
1101 ol.notify_all(CHECK);
1102 } else {
1103 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1104 set_init_thread(NULL); // reset _init_thread before changing _init_state
1105 set_init_state(state);
1106 }
1107 }
1108
1109 Klass* InstanceKlass::implementor() const {
1110 Klass* volatile* k = adr_implementor();
1111 if (k == NULL) {
1112 return NULL;
1113 } else {
1114 // This load races with inserts, and therefore needs acquire.
1115 Klass* kls = Atomic::load_acquire(k);
1116 if (kls != NULL && !kls->is_loader_alive()) {
1117 return NULL; // don't return unloaded class
1118 } else {
1119 return kls;
1120 }
1121 }
1122 }
1123
1124
1125 void InstanceKlass::set_implementor(Klass* k) {
1126 assert_locked_or_safepoint(Compile_lock);
1127 assert(is_interface(), "not interface");
1128 Klass* volatile* addr = adr_implementor();
1129 assert(addr != NULL, "null addr");
1130 if (addr != NULL) {
1131 Atomic::release_store(addr, k);
1132 }
1133 }
1134
1135 int InstanceKlass::nof_implementors() const {
1136 Klass* k = implementor();
1137 if (k == NULL) {
1138 return 0;
1139 } else if (k != this) {
1140 return 1;
1141 } else {
1142 return 2;
1143 }
1144 }
1145
1146 // The embedded _implementor field can only record one implementor.
1147 // When there are more than one implementors, the _implementor field
1148 // is set to the interface Klass* itself. Following are the possible
1149 // values for the _implementor field:
1150 // NULL - no implementor
1151 // implementor Klass* - one implementor
1152 // self - more than one implementor
1153 //
1154 // The _implementor field only exists for interfaces.
1155 void InstanceKlass::add_implementor(Klass* k) {
1156 if (Universe::is_fully_initialized()) {
1157 assert_lock_strong(Compile_lock);
1158 }
1159 assert(is_interface(), "not interface");
1160 // Filter out my subinterfaces.
1161 // (Note: Interfaces are never on the subklass list.)
1162 if (InstanceKlass::cast(k)->is_interface()) return;
1163
1164 // Filter out subclasses whose supers already implement me.
1165 // (Note: CHA must walk subclasses of direct implementors
1166 // in order to locate indirect implementors.)
1167 Klass* sk = k->super();
1168 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1169 // We only need to check one immediate superclass, since the
1170 // implements_interface query looks at transitive_interfaces.
1171 // Any supers of the super have the same (or fewer) transitive_interfaces.
1172 return;
1173
1174 Klass* ik = implementor();
1175 if (ik == NULL) {
1176 set_implementor(k);
1177 } else if (ik != this && ik != k) {
1178 // There is already an implementor. Use itself as an indicator of
1179 // more than one implementors.
1180 set_implementor(this);
1181 }
1182
1183 // The implementor also implements the transitive_interfaces
1184 for (int index = 0; index < local_interfaces()->length(); index++) {
1185 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1186 }
1187 }
1188
1189 void InstanceKlass::init_implementor() {
1190 if (is_interface()) {
1191 set_implementor(NULL);
1192 }
1193 }
1194
1195
1196 void InstanceKlass::process_interfaces(Thread *thread) {
1197 // link this class into the implementors list of every interface it implements
1198 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1199 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1200 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1201 assert(interf->is_interface(), "expected interface");
1202 interf->add_implementor(this);
1203 }
1204 }
1205
1206 bool InstanceKlass::can_be_primary_super_slow() const {
1207 if (is_interface())
1208 return false;
1209 else
1210 return Klass::can_be_primary_super_slow();
1211 }
1212
1213 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1214 Array<InstanceKlass*>* transitive_interfaces) {
1215 // The secondaries are the implemented interfaces.
1216 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1217 int num_secondaries = num_extra_slots + interfaces->length();
1218 if (num_secondaries == 0) {
1219 // Must share this for correct bootstrapping!
1220 set_secondary_supers(Universe::the_empty_klass_array());
1221 return NULL;
1222 } else if (num_extra_slots == 0) {
1223 // The secondary super list is exactly the same as the transitive interfaces, so
1224 // let's use it instead of making a copy.
1225 // Redefine classes has to be careful not to delete this!
1226 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1227 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1228 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1229 return NULL;
1230 } else {
1231 // Copy transitive interfaces to a temporary growable array to be constructed
1232 // into the secondary super list with extra slots.
1233 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1234 for (int i = 0; i < interfaces->length(); i++) {
1235 secondaries->push(interfaces->at(i));
1236 }
1237 return secondaries;
1238 }
1239 }
1240
1241 bool InstanceKlass::implements_interface(Klass* k) const {
1242 if (this == k) return true;
1243 assert(k->is_interface(), "should be an interface class");
1244 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1245 if (transitive_interfaces()->at(i) == k) {
1246 return true;
1247 }
1248 }
1249 return false;
1250 }
1251
1252 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1253 // Verify direct super interface
1254 if (this == k) return true;
1255 assert(k->is_interface(), "should be an interface class");
1256 for (int i = 0; i < local_interfaces()->length(); i++) {
1257 if (local_interfaces()->at(i) == k) {
1258 return true;
1259 }
1260 }
1261 return false;
1262 }
1263
1264 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1265 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1266 int size = objArrayOopDesc::object_size(length);
1267 Klass* ak = array_klass(n, CHECK_NULL);
1268 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1269 /* do_zero */ true, CHECK_NULL);
1270 return o;
1271 }
1272
1273 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1274 if (TraceFinalizerRegistration) {
1275 tty->print("Registered ");
1276 i->print_value_on(tty);
1277 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1278 }
1279 instanceHandle h_i(THREAD, i);
1280 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1281 JavaValue result(T_VOID);
1282 JavaCallArguments args(h_i);
1283 methodHandle mh (THREAD, Universe::finalizer_register_method());
1284 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1285 return h_i();
1286 }
1287
1288 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1289 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1290 int size = size_helper(); // Query before forming handle.
1291
1292 instanceOop i;
1293
1294 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1295 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1296 i = register_finalizer(i, CHECK_NULL);
1297 }
1298 return i;
1299 }
1300
1301 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1302 return instanceHandle(THREAD, allocate_instance(THREAD));
1303 }
1304
1305 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1306 if (is_interface() || is_abstract()) {
1307 ResourceMark rm(THREAD);
1308 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1309 : vmSymbols::java_lang_InstantiationException(), external_name());
1310 }
1311 if (this == SystemDictionary::Class_klass()) {
1312 ResourceMark rm(THREAD);
1313 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1314 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1315 }
1316 }
1317
1318 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1319 // Need load-acquire for lock-free read
1320 if (array_klasses_acquire() == NULL) {
1321 if (or_null) return NULL;
1322
1323 ResourceMark rm(THREAD);
1324 JavaThread *jt = (JavaThread *)THREAD;
1325 {
1326 // Atomic creation of array_klasses
1327 MutexLocker ma(THREAD, MultiArray_lock);
1328
1329 // Check if update has already taken place
1330 if (array_klasses() == NULL) {
1331 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1332 // use 'release' to pair with lock-free load
1333 release_set_array_klasses(k);
1334 }
1335 }
1336 }
1337 // _this will always be set at this point
1338 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1339 if (or_null) {
1340 return oak->array_klass_or_null(n);
1341 }
1342 return oak->array_klass(n, THREAD);
1343 }
1344
1345 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1346 return array_klass_impl(or_null, 1, THREAD);
1347 }
1348
1349 static int call_class_initializer_counter = 0; // for debugging
1350
1351 Method* InstanceKlass::class_initializer() const {
1352 Method* clinit = find_method(
1353 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1354 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1355 return clinit;
1356 }
1357 return NULL;
1358 }
1359
1360 void InstanceKlass::call_class_initializer(TRAPS) {
1361 if (ReplayCompiles &&
1362 (ReplaySuppressInitializers == 1 ||
1363 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1364 // Hide the existence of the initializer for the purpose of replaying the compile
1365 return;
1366 }
1367
1368 methodHandle h_method(THREAD, class_initializer());
1369 assert(!is_initialized(), "we cannot initialize twice");
1370 LogTarget(Info, class, init) lt;
1371 if (lt.is_enabled()) {
1372 ResourceMark rm(THREAD);
1373 LogStream ls(lt);
1374 ls.print("%d Initializing ", call_class_initializer_counter++);
1375 name()->print_value_on(&ls);
1376 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1377 }
1378 if (h_method() != NULL) {
1379 JavaCallArguments args; // No arguments
1380 JavaValue result(T_VOID);
1381 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1382 }
1383 }
1384
1385
1386 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1387 InterpreterOopMap* entry_for) {
1388 // Lazily create the _oop_map_cache at first request
1389 // Lock-free access requires load_acquire.
1390 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1391 if (oop_map_cache == NULL) {
1392 MutexLocker x(OopMapCacheAlloc_lock);
1393 // Check if _oop_map_cache was allocated while we were waiting for this lock
1394 if ((oop_map_cache = _oop_map_cache) == NULL) {
1395 oop_map_cache = new OopMapCache();
1396 // Ensure _oop_map_cache is stable, since it is examined without a lock
1397 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1398 }
1399 }
1400 // _oop_map_cache is constant after init; lookup below does its own locking.
1401 oop_map_cache->lookup(method, bci, entry_for);
1402 }
1403
1404 bool InstanceKlass::contains_field_offset(int offset) {
1405 fieldDescriptor fd;
1406 return find_field_from_offset(offset, false, &fd);
1407 }
1408
1409 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1410 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1411 Symbol* f_name = fs.name();
1412 Symbol* f_sig = fs.signature();
1413 if (f_name == name && f_sig == sig) {
1414 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1415 return true;
1416 }
1417 }
1418 return false;
1419 }
1420
1421
1422 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1423 const int n = local_interfaces()->length();
1424 for (int i = 0; i < n; i++) {
1425 Klass* intf1 = local_interfaces()->at(i);
1426 assert(intf1->is_interface(), "just checking type");
1427 // search for field in current interface
1428 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1429 assert(fd->is_static(), "interface field must be static");
1430 return intf1;
1431 }
1432 // search for field in direct superinterfaces
1433 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1434 if (intf2 != NULL) return intf2;
1435 }
1436 // otherwise field lookup fails
1437 return NULL;
1438 }
1439
1440
1441 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1442 // search order according to newest JVM spec (5.4.3.2, p.167).
1443 // 1) search for field in current klass
1444 if (find_local_field(name, sig, fd)) {
1445 return const_cast<InstanceKlass*>(this);
1446 }
1447 // 2) search for field recursively in direct superinterfaces
1448 { Klass* intf = find_interface_field(name, sig, fd);
1449 if (intf != NULL) return intf;
1450 }
1451 // 3) apply field lookup recursively if superclass exists
1452 { Klass* supr = super();
1453 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1454 }
1455 // 4) otherwise field lookup fails
1456 return NULL;
1457 }
1458
1459
1460 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1461 // search order according to newest JVM spec (5.4.3.2, p.167).
1462 // 1) search for field in current klass
1463 if (find_local_field(name, sig, fd)) {
1464 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1465 }
1466 // 2) search for field recursively in direct superinterfaces
1467 if (is_static) {
1468 Klass* intf = find_interface_field(name, sig, fd);
1469 if (intf != NULL) return intf;
1470 }
1471 // 3) apply field lookup recursively if superclass exists
1472 { Klass* supr = super();
1473 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1474 }
1475 // 4) otherwise field lookup fails
1476 return NULL;
1477 }
1478
1479
1480 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1481 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1482 if (fs.offset() == offset) {
1483 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1484 if (fd->is_static() == is_static) return true;
1485 }
1486 }
1487 return false;
1488 }
1489
1490
1491 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1492 Klass* klass = const_cast<InstanceKlass*>(this);
1493 while (klass != NULL) {
1494 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1495 return true;
1496 }
1497 klass = klass->super();
1498 }
1499 return false;
1500 }
1501
1502
1503 void InstanceKlass::methods_do(void f(Method* method)) {
1504 // Methods aren't stable until they are loaded. This can be read outside
1505 // a lock through the ClassLoaderData for profiling
1506 if (!is_loaded()) {
1507 return;
1508 }
1509
1510 int len = methods()->length();
1511 for (int index = 0; index < len; index++) {
1512 Method* m = methods()->at(index);
1513 assert(m->is_method(), "must be method");
1514 f(m);
1515 }
1516 }
1517
1518
1519 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1520 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1521 if (fs.access_flags().is_static()) {
1522 fieldDescriptor& fd = fs.field_descriptor();
1523 cl->do_field(&fd);
1524 }
1525 }
1526 }
1527
1528
1529 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1530 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1531 if (fs.access_flags().is_static()) {
1532 fieldDescriptor& fd = fs.field_descriptor();
1533 f(&fd, mirror, CHECK);
1534 }
1535 }
1536 }
1537
1538
1539 static int compare_fields_by_offset(int* a, int* b) {
1540 return a[0] - b[0];
1541 }
1542
1543 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1544 InstanceKlass* super = superklass();
1545 if (super != NULL) {
1546 super->do_nonstatic_fields(cl);
1547 }
1548 fieldDescriptor fd;
1549 int length = java_fields_count();
1550 // In DebugInfo nonstatic fields are sorted by offset.
1551 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1552 int j = 0;
1553 for (int i = 0; i < length; i += 1) {
1554 fd.reinitialize(this, i);
1555 if (!fd.is_static()) {
1556 fields_sorted[j + 0] = fd.offset();
1557 fields_sorted[j + 1] = i;
1558 j += 2;
1559 }
1560 }
1561 if (j > 0) {
1562 length = j;
1563 // _sort_Fn is defined in growableArray.hpp.
1564 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1565 for (int i = 0; i < length; i += 2) {
1566 fd.reinitialize(this, fields_sorted[i + 1]);
1567 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1568 cl->do_field(&fd);
1569 }
1570 }
1571 FREE_C_HEAP_ARRAY(int, fields_sorted);
1572 }
1573
1574
1575 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1576 if (array_klasses() != NULL)
1577 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1578 }
1579
1580 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1581 if (array_klasses() != NULL)
1582 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1583 }
1584
1585 #ifdef ASSERT
1586 static int linear_search(const Array<Method*>* methods,
1587 const Symbol* name,
1588 const Symbol* signature) {
1589 const int len = methods->length();
1590 for (int index = 0; index < len; index++) {
1591 const Method* const m = methods->at(index);
1592 assert(m->is_method(), "must be method");
1593 if (m->signature() == signature && m->name() == name) {
1594 return index;
1595 }
1596 }
1597 return -1;
1598 }
1599 #endif
1600
1601 bool InstanceKlass::_disable_method_binary_search = false;
1602
1603 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1604 int len = methods->length();
1605 int l = 0;
1606 int h = len - 1;
1607 while (l <= h) {
1608 Method* m = methods->at(l);
1609 if (m->name() == name) {
1610 return l;
1611 }
1612 l++;
1613 }
1614 return -1;
1615 }
1616
1617 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1618 if (_disable_method_binary_search) {
1619 assert(DynamicDumpSharedSpaces, "must be");
1620 // At the final stage of dynamic dumping, the methods array may not be sorted
1621 // by ascending addresses of their names, so we can't use binary search anymore.
1622 // However, methods with the same name are still laid out consecutively inside the
1623 // methods array, so let's look for the first one that matches.
1624 return linear_search(methods, name);
1625 }
1626
1627 int len = methods->length();
1628 int l = 0;
1629 int h = len - 1;
1630
1631 // methods are sorted by ascending addresses of their names, so do binary search
1632 while (l <= h) {
1633 int mid = (l + h) >> 1;
1634 Method* m = methods->at(mid);
1635 assert(m->is_method(), "must be method");
1636 int res = m->name()->fast_compare(name);
1637 if (res == 0) {
1638 return mid;
1639 } else if (res < 0) {
1640 l = mid + 1;
1641 } else {
1642 h = mid - 1;
1643 }
1644 }
1645 return -1;
1646 }
1647
1648 // find_method looks up the name/signature in the local methods array
1649 Method* InstanceKlass::find_method(const Symbol* name,
1650 const Symbol* signature) const {
1651 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1652 }
1653
1654 Method* InstanceKlass::find_method_impl(const Symbol* name,
1655 const Symbol* signature,
1656 OverpassLookupMode overpass_mode,
1657 StaticLookupMode static_mode,
1658 PrivateLookupMode private_mode) const {
1659 return InstanceKlass::find_method_impl(methods(),
1660 name,
1661 signature,
1662 overpass_mode,
1663 static_mode,
1664 private_mode);
1665 }
1666
1667 // find_instance_method looks up the name/signature in the local methods array
1668 // and skips over static methods
1669 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1670 const Symbol* name,
1671 const Symbol* signature,
1672 PrivateLookupMode private_mode) {
1673 Method* const meth = InstanceKlass::find_method_impl(methods,
1674 name,
1675 signature,
1676 find_overpass,
1677 skip_static,
1678 private_mode);
1679 assert(((meth == NULL) || !meth->is_static()),
1680 "find_instance_method should have skipped statics");
1681 return meth;
1682 }
1683
1684 // find_instance_method looks up the name/signature in the local methods array
1685 // and skips over static methods
1686 Method* InstanceKlass::find_instance_method(const Symbol* name,
1687 const Symbol* signature,
1688 PrivateLookupMode private_mode) const {
1689 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1690 }
1691
1692 // Find looks up the name/signature in the local methods array
1693 // and filters on the overpass, static and private flags
1694 // This returns the first one found
1695 // note that the local methods array can have up to one overpass, one static
1696 // and one instance (private or not) with the same name/signature
1697 Method* InstanceKlass::find_local_method(const Symbol* name,
1698 const Symbol* signature,
1699 OverpassLookupMode overpass_mode,
1700 StaticLookupMode static_mode,
1701 PrivateLookupMode private_mode) const {
1702 return InstanceKlass::find_method_impl(methods(),
1703 name,
1704 signature,
1705 overpass_mode,
1706 static_mode,
1707 private_mode);
1708 }
1709
1710 // Find looks up the name/signature in the local methods array
1711 // and filters on the overpass, static and private flags
1712 // This returns the first one found
1713 // note that the local methods array can have up to one overpass, one static
1714 // and one instance (private or not) with the same name/signature
1715 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1716 const Symbol* name,
1717 const Symbol* signature,
1718 OverpassLookupMode overpass_mode,
1719 StaticLookupMode static_mode,
1720 PrivateLookupMode private_mode) {
1721 return InstanceKlass::find_method_impl(methods,
1722 name,
1723 signature,
1724 overpass_mode,
1725 static_mode,
1726 private_mode);
1727 }
1728
1729 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1730 const Symbol* name,
1731 const Symbol* signature) {
1732 return InstanceKlass::find_method_impl(methods,
1733 name,
1734 signature,
1735 find_overpass,
1736 find_static,
1737 find_private);
1738 }
1739
1740 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1741 const Symbol* name,
1742 const Symbol* signature,
1743 OverpassLookupMode overpass_mode,
1744 StaticLookupMode static_mode,
1745 PrivateLookupMode private_mode) {
1746 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1747 return hit >= 0 ? methods->at(hit): NULL;
1748 }
1749
1750 // true if method matches signature and conforms to skipping_X conditions.
1751 static bool method_matches(const Method* m,
1752 const Symbol* signature,
1753 bool skipping_overpass,
1754 bool skipping_static,
1755 bool skipping_private) {
1756 return ((m->signature() == signature) &&
1757 (!skipping_overpass || !m->is_overpass()) &&
1758 (!skipping_static || !m->is_static()) &&
1759 (!skipping_private || !m->is_private()));
1760 }
1761
1762 // Used directly for default_methods to find the index into the
1763 // default_vtable_indices, and indirectly by find_method
1764 // find_method_index looks in the local methods array to return the index
1765 // of the matching name/signature. If, overpass methods are being ignored,
1766 // the search continues to find a potential non-overpass match. This capability
1767 // is important during method resolution to prefer a static method, for example,
1768 // over an overpass method.
1769 // There is the possibility in any _method's array to have the same name/signature
1770 // for a static method, an overpass method and a local instance method
1771 // To correctly catch a given method, the search criteria may need
1772 // to explicitly skip the other two. For local instance methods, it
1773 // is often necessary to skip private methods
1774 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1775 const Symbol* name,
1776 const Symbol* signature,
1777 OverpassLookupMode overpass_mode,
1778 StaticLookupMode static_mode,
1779 PrivateLookupMode private_mode) {
1780 const bool skipping_overpass = (overpass_mode == skip_overpass);
1781 const bool skipping_static = (static_mode == skip_static);
1782 const bool skipping_private = (private_mode == skip_private);
1783 const int hit = quick_search(methods, name);
1784 if (hit != -1) {
1785 const Method* const m = methods->at(hit);
1786
1787 // Do linear search to find matching signature. First, quick check
1788 // for common case, ignoring overpasses if requested.
1789 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1790 return hit;
1791 }
1792
1793 // search downwards through overloaded methods
1794 int i;
1795 for (i = hit - 1; i >= 0; --i) {
1796 const Method* const m = methods->at(i);
1797 assert(m->is_method(), "must be method");
1798 if (m->name() != name) {
1799 break;
1800 }
1801 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1802 return i;
1803 }
1804 }
1805 // search upwards
1806 for (i = hit + 1; i < methods->length(); ++i) {
1807 const Method* const m = methods->at(i);
1808 assert(m->is_method(), "must be method");
1809 if (m->name() != name) {
1810 break;
1811 }
1812 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1813 return i;
1814 }
1815 }
1816 // not found
1817 #ifdef ASSERT
1818 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1819 linear_search(methods, name, signature);
1820 assert(-1 == index, "binary search should have found entry %d", index);
1821 #endif
1822 }
1823 return -1;
1824 }
1825
1826 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1827 return find_method_by_name(methods(), name, end);
1828 }
1829
1830 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1831 const Symbol* name,
1832 int* end_ptr) {
1833 assert(end_ptr != NULL, "just checking");
1834 int start = quick_search(methods, name);
1835 int end = start + 1;
1836 if (start != -1) {
1837 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1838 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1839 *end_ptr = end;
1840 return start;
1841 }
1842 return -1;
1843 }
1844
1845 // uncached_lookup_method searches both the local class methods array and all
1846 // superclasses methods arrays, skipping any overpass methods in superclasses,
1847 // and possibly skipping private methods.
1848 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1849 const Symbol* signature,
1850 OverpassLookupMode overpass_mode,
1851 PrivateLookupMode private_mode) const {
1852 OverpassLookupMode overpass_local_mode = overpass_mode;
1853 const Klass* klass = this;
1854 while (klass != NULL) {
1855 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1856 signature,
1857 overpass_local_mode,
1858 find_static,
1859 private_mode);
1860 if (method != NULL) {
1861 return method;
1862 }
1863 klass = klass->super();
1864 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1865 }
1866 return NULL;
1867 }
1868
1869 #ifdef ASSERT
1870 // search through class hierarchy and return true if this class or
1871 // one of the superclasses was redefined
1872 bool InstanceKlass::has_redefined_this_or_super() const {
1873 const Klass* klass = this;
1874 while (klass != NULL) {
1875 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1876 return true;
1877 }
1878 klass = klass->super();
1879 }
1880 return false;
1881 }
1882 #endif
1883
1884 // lookup a method in the default methods list then in all transitive interfaces
1885 // Do NOT return private or static methods
1886 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1887 Symbol* signature) const {
1888 Method* m = NULL;
1889 if (default_methods() != NULL) {
1890 m = find_method(default_methods(), name, signature);
1891 }
1892 // Look up interfaces
1893 if (m == NULL) {
1894 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1895 }
1896 return m;
1897 }
1898
1899 // lookup a method in all the interfaces that this class implements
1900 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1901 // They should only be found in the initial InterfaceMethodRef
1902 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1903 Symbol* signature,
1904 DefaultsLookupMode defaults_mode) const {
1905 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1906 int num_ifs = all_ifs->length();
1907 InstanceKlass *ik = NULL;
1908 for (int i = 0; i < num_ifs; i++) {
1909 ik = all_ifs->at(i);
1910 Method* m = ik->lookup_method(name, signature);
1911 if (m != NULL && m->is_public() && !m->is_static() &&
1912 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1913 return m;
1914 }
1915 }
1916 return NULL;
1917 }
1918
1919 /* jni_id_for_impl for jfieldIds only */
1920 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1921 MutexLocker ml(JfieldIdCreation_lock);
1922 // Retry lookup after we got the lock
1923 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1924 if (probe == NULL) {
1925 // Slow case, allocate new static field identifier
1926 probe = new JNIid(this, offset, jni_ids());
1927 set_jni_ids(probe);
1928 }
1929 return probe;
1930 }
1931
1932
1933 /* jni_id_for for jfieldIds only */
1934 JNIid* InstanceKlass::jni_id_for(int offset) {
1935 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1936 if (probe == NULL) {
1937 probe = jni_id_for_impl(offset);
1938 }
1939 return probe;
1940 }
1941
1942 u2 InstanceKlass::enclosing_method_data(int offset) const {
1943 const Array<jushort>* const inner_class_list = inner_classes();
1944 if (inner_class_list == NULL) {
1945 return 0;
1946 }
1947 const int length = inner_class_list->length();
1948 if (length % inner_class_next_offset == 0) {
1949 return 0;
1950 }
1951 const int index = length - enclosing_method_attribute_size;
1952 assert(offset < enclosing_method_attribute_size, "invalid offset");
1953 return inner_class_list->at(index + offset);
1954 }
1955
1956 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1957 u2 method_index) {
1958 Array<jushort>* inner_class_list = inner_classes();
1959 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1960 int length = inner_class_list->length();
1961 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1962 int index = length - enclosing_method_attribute_size;
1963 inner_class_list->at_put(
1964 index + enclosing_method_class_index_offset, class_index);
1965 inner_class_list->at_put(
1966 index + enclosing_method_method_index_offset, method_index);
1967 }
1968 }
1969
1970 // Lookup or create a jmethodID.
1971 // This code is called by the VMThread and JavaThreads so the
1972 // locking has to be done very carefully to avoid deadlocks
1973 // and/or other cache consistency problems.
1974 //
1975 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1976 size_t idnum = (size_t)method_h->method_idnum();
1977 jmethodID* jmeths = methods_jmethod_ids_acquire();
1978 size_t length = 0;
1979 jmethodID id = NULL;
1980
1981 // We use a double-check locking idiom here because this cache is
1982 // performance sensitive. In the normal system, this cache only
1983 // transitions from NULL to non-NULL which is safe because we use
1984 // release_set_methods_jmethod_ids() to advertise the new cache.
1985 // A partially constructed cache should never be seen by a racing
1986 // thread. We also use release_store() to save a new jmethodID
1987 // in the cache so a partially constructed jmethodID should never be
1988 // seen either. Cache reads of existing jmethodIDs proceed without a
1989 // lock, but cache writes of a new jmethodID requires uniqueness and
1990 // creation of the cache itself requires no leaks so a lock is
1991 // generally acquired in those two cases.
1992 //
1993 // If the RedefineClasses() API has been used, then this cache can
1994 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1995 // Cache creation requires no leaks and we require safety between all
1996 // cache accesses and freeing of the old cache so a lock is generally
1997 // acquired when the RedefineClasses() API has been used.
1998
1999 if (jmeths != NULL) {
2000 // the cache already exists
2001 if (!idnum_can_increment()) {
2002 // the cache can't grow so we can just get the current values
2003 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2004 } else {
2005 // cache can grow so we have to be more careful
2006 if (Threads::number_of_threads() == 0 ||
2007 SafepointSynchronize::is_at_safepoint()) {
2008 // we're single threaded or at a safepoint - no locking needed
2009 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2010 } else {
2011 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2012 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2013 }
2014 }
2015 }
2016 // implied else:
2017 // we need to allocate a cache so default length and id values are good
2018
2019 if (jmeths == NULL || // no cache yet
2020 length <= idnum || // cache is too short
2021 id == NULL) { // cache doesn't contain entry
2022
2023 // This function can be called by the VMThread so we have to do all
2024 // things that might block on a safepoint before grabbing the lock.
2025 // Otherwise, we can deadlock with the VMThread or have a cache
2026 // consistency issue. These vars keep track of what we might have
2027 // to free after the lock is dropped.
2028 jmethodID to_dealloc_id = NULL;
2029 jmethodID* to_dealloc_jmeths = NULL;
2030
2031 // may not allocate new_jmeths or use it if we allocate it
2032 jmethodID* new_jmeths = NULL;
2033 if (length <= idnum) {
2034 // allocate a new cache that might be used
2035 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2036 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2037 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2038 // cache size is stored in element[0], other elements offset by one
2039 new_jmeths[0] = (jmethodID)size;
2040 }
2041
2042 // allocate a new jmethodID that might be used
2043 jmethodID new_id = NULL;
2044 if (method_h->is_old() && !method_h->is_obsolete()) {
2045 // The method passed in is old (but not obsolete), we need to use the current version
2046 Method* current_method = method_with_idnum((int)idnum);
2047 assert(current_method != NULL, "old and but not obsolete, so should exist");
2048 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2049 } else {
2050 // It is the current version of the method or an obsolete method,
2051 // use the version passed in
2052 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2053 }
2054
2055 if (Threads::number_of_threads() == 0 ||
2056 SafepointSynchronize::is_at_safepoint()) {
2057 // we're single threaded or at a safepoint - no locking needed
2058 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2059 &to_dealloc_id, &to_dealloc_jmeths);
2060 } else {
2061 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2062 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2063 &to_dealloc_id, &to_dealloc_jmeths);
2064 }
2065
2066 // The lock has been dropped so we can free resources.
2067 // Free up either the old cache or the new cache if we allocated one.
2068 if (to_dealloc_jmeths != NULL) {
2069 FreeHeap(to_dealloc_jmeths);
2070 }
2071 // free up the new ID since it wasn't needed
2072 if (to_dealloc_id != NULL) {
2073 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2074 }
2075 }
2076 return id;
2077 }
2078
2079 // Figure out how many jmethodIDs haven't been allocated, and make
2080 // sure space for them is pre-allocated. This makes getting all
2081 // method ids much, much faster with classes with more than 8
2082 // methods, and has a *substantial* effect on performance with jvmti
2083 // code that loads all jmethodIDs for all classes.
2084 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2085 int new_jmeths = 0;
2086 int length = methods()->length();
2087 for (int index = start_offset; index < length; index++) {
2088 Method* m = methods()->at(index);
2089 jmethodID id = m->find_jmethod_id_or_null();
2090 if (id == NULL) {
2091 new_jmeths++;
2092 }
2093 }
2094 if (new_jmeths != 0) {
2095 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2096 }
2097 }
2098
2099 // Common code to fetch the jmethodID from the cache or update the
2100 // cache with the new jmethodID. This function should never do anything
2101 // that causes the caller to go to a safepoint or we can deadlock with
2102 // the VMThread or have cache consistency issues.
2103 //
2104 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2105 size_t idnum, jmethodID new_id,
2106 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2107 jmethodID** to_dealloc_jmeths_p) {
2108 assert(new_id != NULL, "sanity check");
2109 assert(to_dealloc_id_p != NULL, "sanity check");
2110 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2111 assert(Threads::number_of_threads() == 0 ||
2112 SafepointSynchronize::is_at_safepoint() ||
2113 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2114
2115 // reacquire the cache - we are locked, single threaded or at a safepoint
2116 jmethodID* jmeths = methods_jmethod_ids_acquire();
2117 jmethodID id = NULL;
2118 size_t length = 0;
2119
2120 if (jmeths == NULL || // no cache yet
2121 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2122 if (jmeths != NULL) {
2123 // copy any existing entries from the old cache
2124 for (size_t index = 0; index < length; index++) {
2125 new_jmeths[index+1] = jmeths[index+1];
2126 }
2127 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2128 }
2129 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2130 } else {
2131 // fetch jmethodID (if any) from the existing cache
2132 id = jmeths[idnum+1];
2133 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2134 }
2135 if (id == NULL) {
2136 // No matching jmethodID in the existing cache or we have a new
2137 // cache or we just grew the cache. This cache write is done here
2138 // by the first thread to win the foot race because a jmethodID
2139 // needs to be unique once it is generally available.
2140 id = new_id;
2141
2142 // The jmethodID cache can be read while unlocked so we have to
2143 // make sure the new jmethodID is complete before installing it
2144 // in the cache.
2145 Atomic::release_store(&jmeths[idnum+1], id);
2146 } else {
2147 *to_dealloc_id_p = new_id; // save new id for later delete
2148 }
2149 return id;
2150 }
2151
2152
2153 // Common code to get the jmethodID cache length and the jmethodID
2154 // value at index idnum if there is one.
2155 //
2156 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2157 size_t idnum, size_t *length_p, jmethodID* id_p) {
2158 assert(cache != NULL, "sanity check");
2159 assert(length_p != NULL, "sanity check");
2160 assert(id_p != NULL, "sanity check");
2161
2162 // cache size is stored in element[0], other elements offset by one
2163 *length_p = (size_t)cache[0];
2164 if (*length_p <= idnum) { // cache is too short
2165 *id_p = NULL;
2166 } else {
2167 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2168 }
2169 }
2170
2171
2172 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2173 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2174 size_t idnum = (size_t)method->method_idnum();
2175 jmethodID* jmeths = methods_jmethod_ids_acquire();
2176 size_t length; // length assigned as debugging crumb
2177 jmethodID id = NULL;
2178 if (jmeths != NULL && // If there is a cache
2179 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2180 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2181 }
2182 return id;
2183 }
2184
2185 inline DependencyContext InstanceKlass::dependencies() {
2186 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2187 return dep_context;
2188 }
2189
2190 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2191 return dependencies().mark_dependent_nmethods(changes);
2192 }
2193
2194 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2195 dependencies().add_dependent_nmethod(nm);
2196 }
2197
2198 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2199 dependencies().remove_dependent_nmethod(nm);
2200 }
2201
2202 void InstanceKlass::clean_dependency_context() {
2203 dependencies().clean_unloading_dependents();
2204 }
2205
2206 #ifndef PRODUCT
2207 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2208 dependencies().print_dependent_nmethods(verbose);
2209 }
2210
2211 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2212 return dependencies().is_dependent_nmethod(nm);
2213 }
2214 #endif //PRODUCT
2215
2216 void InstanceKlass::clean_weak_instanceklass_links() {
2217 clean_implementors_list();
2218 clean_method_data();
2219 }
2220
2221 void InstanceKlass::clean_implementors_list() {
2222 assert(is_loader_alive(), "this klass should be live");
2223 if (is_interface()) {
2224 assert (ClassUnloading, "only called for ClassUnloading");
2225 for (;;) {
2226 // Use load_acquire due to competing with inserts
2227 Klass* impl = Atomic::load_acquire(adr_implementor());
2228 if (impl != NULL && !impl->is_loader_alive()) {
2229 // NULL this field, might be an unloaded klass or NULL
2230 Klass* volatile* klass = adr_implementor();
2231 if (Atomic::cmpxchg(klass, impl, (Klass*)NULL) == impl) {
2232 // Successfully unlinking implementor.
2233 if (log_is_enabled(Trace, class, unload)) {
2234 ResourceMark rm;
2235 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2236 }
2237 return;
2238 }
2239 } else {
2240 return;
2241 }
2242 }
2243 }
2244 }
2245
2246 void InstanceKlass::clean_method_data() {
2247 for (int m = 0; m < methods()->length(); m++) {
2248 MethodData* mdo = methods()->at(m)->method_data();
2249 if (mdo != NULL) {
2250 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock());
2251 mdo->clean_method_data(/*always_clean*/false);
2252 }
2253 }
2254 }
2255
2256 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2257 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2258 ResourceMark rm;
2259 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2260 return false;
2261 }
2262
2263 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2264 if (local_interfaces != NULL) {
2265 int length = local_interfaces->length();
2266 for (int i = 0; i < length; i++) {
2267 InstanceKlass* intf = local_interfaces->at(i);
2268 if (!intf->has_passed_fingerprint_check()) {
2269 ResourceMark rm;
2270 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2271 return false;
2272 }
2273 }
2274 }
2275
2276 return true;
2277 }
2278
2279 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2280 #if INCLUDE_AOT
2281 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2282 if (CalculateClassFingerprint) {
2283 // (1) We are running AOT to generate a shared library.
2284 return true;
2285 }
2286 if (Arguments::is_dumping_archive()) {
2287 // (2) We are running -Xshare:dump or -XX:ArchiveClassesAtExit to create a shared archive
2288 return true;
2289 }
2290 if (UseAOT && is_unsafe_anonymous) {
2291 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2292 return true;
2293 }
2294 #endif
2295
2296 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2297 // but do not store the 64-bit fingerprint to save space.
2298 return false;
2299 }
2300
2301 bool InstanceKlass::has_stored_fingerprint() const {
2302 #if INCLUDE_AOT
2303 return should_store_fingerprint() || is_shared();
2304 #else
2305 return false;
2306 #endif
2307 }
2308
2309 uint64_t InstanceKlass::get_stored_fingerprint() const {
2310 address adr = adr_fingerprint();
2311 if (adr != NULL) {
2312 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2313 }
2314 return 0;
2315 }
2316
2317 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2318 address adr = adr_fingerprint();
2319 if (adr != NULL) {
2320 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2321
2322 ResourceMark rm;
2323 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2324 }
2325 }
2326
2327 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2328 Klass::metaspace_pointers_do(it);
2329
2330 if (log_is_enabled(Trace, cds)) {
2331 ResourceMark rm;
2332 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2333 }
2334
2335 it->push(&_annotations);
2336 it->push((Klass**)&_array_klasses);
2337 it->push(&_constants);
2338 it->push(&_inner_classes);
2339 it->push(&_array_name);
2340 #if INCLUDE_JVMTI
2341 it->push(&_previous_versions);
2342 #endif
2343 it->push(&_methods);
2344 it->push(&_default_methods);
2345 it->push(&_local_interfaces);
2346 it->push(&_transitive_interfaces);
2347 it->push(&_method_ordering);
2348 it->push(&_default_vtable_indices);
2349 it->push(&_fields);
2350
2351 if (itable_length() > 0) {
2352 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2353 int method_table_offset_in_words = ioe->offset()/wordSize;
2354 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2355 / itableOffsetEntry::size();
2356
2357 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2358 if (ioe->interface_klass() != NULL) {
2359 it->push(ioe->interface_klass_addr());
2360 itableMethodEntry* ime = ioe->first_method_entry(this);
2361 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2362 for (int index = 0; index < n; index ++) {
2363 it->push(ime[index].method_addr());
2364 }
2365 }
2366 }
2367 }
2368
2369 it->push(&_nest_members);
2370 it->push(&_record_components);
2371 }
2372
2373 void InstanceKlass::remove_unshareable_info() {
2374 Klass::remove_unshareable_info();
2375
2376 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2377 // Classes are attempted to link during dumping and may fail,
2378 // but these classes are still in the dictionary and class list in CLD.
2379 // If the class has failed verification, there is nothing else to remove.
2380 return;
2381 }
2382
2383 // Reset to the 'allocated' state to prevent any premature accessing to
2384 // a shared class at runtime while the class is still being loaded and
2385 // restored. A class' init_state is set to 'loaded' at runtime when it's
2386 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2387 _init_state = allocated;
2388
2389 { // Otherwise this needs to take out the Compile_lock.
2390 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2391 init_implementor();
2392 }
2393
2394 constants()->remove_unshareable_info();
2395
2396 for (int i = 0; i < methods()->length(); i++) {
2397 Method* m = methods()->at(i);
2398 m->remove_unshareable_info();
2399 }
2400
2401 // do array classes also.
2402 if (array_klasses() != NULL) {
2403 array_klasses()->remove_unshareable_info();
2404 }
2405
2406 // These are not allocated from metaspace. They are safe to set to NULL.
2407 _source_debug_extension = NULL;
2408 _dep_context = NULL;
2409 _osr_nmethods_head = NULL;
2410 #if INCLUDE_JVMTI
2411 _breakpoints = NULL;
2412 _previous_versions = NULL;
2413 _cached_class_file = NULL;
2414 _jvmti_cached_class_field_map = NULL;
2415 #endif
2416
2417 _init_thread = NULL;
2418 _methods_jmethod_ids = NULL;
2419 _jni_ids = NULL;
2420 _oop_map_cache = NULL;
2421 // clear _nest_host to ensure re-load at runtime
2422 _nest_host = NULL;
2423 _package_entry = NULL;
2424 _dep_context_last_cleaned = 0;
2425 }
2426
2427 void InstanceKlass::remove_java_mirror() {
2428 Klass::remove_java_mirror();
2429
2430 // do array classes also.
2431 if (array_klasses() != NULL) {
2432 array_klasses()->remove_java_mirror();
2433 }
2434 }
2435
2436 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2437 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2438 // before the InstanceKlass is added to the SystemDictionary. Make
2439 // sure the current state is <loaded.
2440 assert(!is_loaded(), "invalid init state");
2441 set_package(loader_data, CHECK);
2442 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2443
2444 Array<Method*>* methods = this->methods();
2445 int num_methods = methods->length();
2446 for (int index = 0; index < num_methods; ++index) {
2447 methods->at(index)->restore_unshareable_info(CHECK);
2448 }
2449 if (JvmtiExport::has_redefined_a_class()) {
2450 // Reinitialize vtable because RedefineClasses may have changed some
2451 // entries in this vtable for super classes so the CDS vtable might
2452 // point to old or obsolete entries. RedefineClasses doesn't fix up
2453 // vtables in the shared system dictionary, only the main one.
2454 // It also redefines the itable too so fix that too.
2455 vtable().initialize_vtable(false, CHECK);
2456 itable().initialize_itable(false, CHECK);
2457 }
2458
2459 // restore constant pool resolved references
2460 constants()->restore_unshareable_info(CHECK);
2461
2462 if (array_klasses() != NULL) {
2463 // Array classes have null protection domain.
2464 // --> see ArrayKlass::complete_create_array_klass()
2465 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2466 }
2467
2468 // Initialize current biased locking state.
2469 if (UseBiasedLocking && BiasedLocking::enabled()) {
2470 set_prototype_header(markWord::biased_locking_prototype());
2471 }
2472 }
2473
2474 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) {
2475 switch (loader_type) {
2476 case ClassLoader::BOOT_LOADER:
2477 _misc_flags |= _misc_is_shared_boot_class;
2478 break;
2479 case ClassLoader::PLATFORM_LOADER:
2480 _misc_flags |= _misc_is_shared_platform_class;
2481 break;
2482 case ClassLoader::APP_LOADER:
2483 _misc_flags |= _misc_is_shared_app_class;
2484 break;
2485 default:
2486 ShouldNotReachHere();
2487 break;
2488 }
2489 }
2490
2491 #if INCLUDE_JVMTI
2492 static void clear_all_breakpoints(Method* m) {
2493 m->clear_all_breakpoints();
2494 }
2495 #endif
2496
2497 void InstanceKlass::unload_class(InstanceKlass* ik) {
2498 // Release dependencies.
2499 ik->dependencies().remove_all_dependents();
2500
2501 // notify the debugger
2502 if (JvmtiExport::should_post_class_unload()) {
2503 JvmtiExport::post_class_unload(ik);
2504 }
2505
2506 // notify ClassLoadingService of class unload
2507 ClassLoadingService::notify_class_unloaded(ik);
2508
2509 if (Arguments::is_dumping_archive()) {
2510 SystemDictionaryShared::remove_dumptime_info(ik);
2511 }
2512
2513 if (log_is_enabled(Info, class, unload)) {
2514 ResourceMark rm;
2515 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik));
2516 }
2517
2518 Events::log_class_unloading(Thread::current(), ik);
2519
2520 #if INCLUDE_JFR
2521 assert(ik != NULL, "invariant");
2522 EventClassUnload event;
2523 event.set_unloadedClass(ik);
2524 event.set_definingClassLoader(ik->class_loader_data());
2525 event.commit();
2526 #endif
2527 }
2528
2529 static void method_release_C_heap_structures(Method* m) {
2530 m->release_C_heap_structures();
2531 }
2532
2533 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2534 // Clean up C heap
2535 ik->release_C_heap_structures();
2536 ik->constants()->release_C_heap_structures();
2537
2538 // Deallocate and call destructors for MDO mutexes
2539 ik->methods_do(method_release_C_heap_structures);
2540
2541 }
2542
2543 void InstanceKlass::release_C_heap_structures() {
2544 // Can't release the constant pool here because the constant pool can be
2545 // deallocated separately from the InstanceKlass for default methods and
2546 // redefine classes.
2547
2548 // Deallocate oop map cache
2549 if (_oop_map_cache != NULL) {
2550 delete _oop_map_cache;
2551 _oop_map_cache = NULL;
2552 }
2553
2554 // Deallocate JNI identifiers for jfieldIDs
2555 JNIid::deallocate(jni_ids());
2556 set_jni_ids(NULL);
2557
2558 jmethodID* jmeths = methods_jmethod_ids_acquire();
2559 if (jmeths != (jmethodID*)NULL) {
2560 release_set_methods_jmethod_ids(NULL);
2561 FreeHeap(jmeths);
2562 }
2563
2564 assert(_dep_context == NULL,
2565 "dependencies should already be cleaned");
2566
2567 #if INCLUDE_JVMTI
2568 // Deallocate breakpoint records
2569 if (breakpoints() != 0x0) {
2570 methods_do(clear_all_breakpoints);
2571 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2572 }
2573
2574 // deallocate the cached class file
2575 if (_cached_class_file != NULL) {
2576 os::free(_cached_class_file);
2577 _cached_class_file = NULL;
2578 }
2579 #endif
2580
2581 // Decrement symbol reference counts associated with the unloaded class.
2582 if (_name != NULL) _name->decrement_refcount();
2583 // unreference array name derived from this class name (arrays of an unloaded
2584 // class can't be referenced anymore).
2585 if (_array_name != NULL) _array_name->decrement_refcount();
2586 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2587 }
2588
2589 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2590 if (array == NULL) {
2591 _source_debug_extension = NULL;
2592 } else {
2593 // Adding one to the attribute length in order to store a null terminator
2594 // character could cause an overflow because the attribute length is
2595 // already coded with an u4 in the classfile, but in practice, it's
2596 // unlikely to happen.
2597 assert((length+1) > length, "Overflow checking");
2598 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2599 for (int i = 0; i < length; i++) {
2600 sde[i] = array[i];
2601 }
2602 sde[length] = '\0';
2603 _source_debug_extension = sde;
2604 }
2605 }
2606
2607 const char* InstanceKlass::signature_name() const {
2608 int hash_len = 0;
2609 char hash_buf[40];
2610
2611 // If this is an unsafe anonymous class, append a hash to make the name unique
2612 if (is_unsafe_anonymous()) {
2613 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2614 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2615 hash_len = (int)strlen(hash_buf);
2616 }
2617
2618 // Get the internal name as a c string
2619 const char* src = (const char*) (name()->as_C_string());
2620 const int src_length = (int)strlen(src);
2621
2622 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2623
2624 // Add L as type indicator
2625 int dest_index = 0;
2626 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2627
2628 // Add the actual class name
2629 for (int src_index = 0; src_index < src_length; ) {
2630 dest[dest_index++] = src[src_index++];
2631 }
2632
2633 // If we have a hash, append it
2634 for (int hash_index = 0; hash_index < hash_len; ) {
2635 dest[dest_index++] = hash_buf[hash_index++];
2636 }
2637
2638 // Add the semicolon and the NULL
2639 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
2640 dest[dest_index] = '\0';
2641 return dest;
2642 }
2643
2644 ModuleEntry* InstanceKlass::module() const {
2645 // For an unsafe anonymous class return the host class' module
2646 if (is_unsafe_anonymous()) {
2647 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2648 return unsafe_anonymous_host()->module();
2649 }
2650
2651 // Class is in a named package
2652 if (!in_unnamed_package()) {
2653 return _package_entry->module();
2654 }
2655
2656 // Class is in an unnamed package, return its loader's unnamed module
2657 return class_loader_data()->unnamed_module();
2658 }
2659
2660 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2661
2662 // ensure java/ packages only loaded by boot or platform builtin loaders
2663 check_prohibited_package(name(), loader_data, CHECK);
2664
2665 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(name());
2666
2667 if (pkg_name != NULL && loader_data != NULL) {
2668
2669 // Find in class loader's package entry table.
2670 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2671
2672 // If the package name is not found in the loader's package
2673 // entry table, it is an indication that the package has not
2674 // been defined. Consider it defined within the unnamed module.
2675 if (_package_entry == NULL) {
2676 ResourceMark rm(THREAD);
2677
2678 if (!ModuleEntryTable::javabase_defined()) {
2679 // Before java.base is defined during bootstrapping, define all packages in
2680 // the java.base module. If a non-java.base package is erroneously placed
2681 // in the java.base module it will be caught later when java.base
2682 // is defined by ModuleEntryTable::verify_javabase_packages check.
2683 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2684 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2685 } else {
2686 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2687 _package_entry = loader_data->packages()->lookup(pkg_name,
2688 loader_data->unnamed_module());
2689 }
2690
2691 // A package should have been successfully created
2692 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2693 name()->as_C_string(), loader_data->loader_name_and_id());
2694 }
2695
2696 if (log_is_enabled(Debug, module)) {
2697 ResourceMark rm(THREAD);
2698 ModuleEntry* m = _package_entry->module();
2699 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2700 external_name(),
2701 pkg_name->as_C_string(),
2702 loader_data->loader_name_and_id(),
2703 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2704 }
2705 } else {
2706 ResourceMark rm(THREAD);
2707 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2708 external_name(),
2709 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2710 UNNAMED_MODULE);
2711 }
2712 }
2713
2714
2715 // different versions of is_same_class_package
2716
2717 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2718 oop classloader1 = this->class_loader();
2719 PackageEntry* classpkg1 = this->package();
2720 if (class2->is_objArray_klass()) {
2721 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2722 }
2723
2724 oop classloader2;
2725 PackageEntry* classpkg2;
2726 if (class2->is_instance_klass()) {
2727 classloader2 = class2->class_loader();
2728 classpkg2 = class2->package();
2729 } else {
2730 assert(class2->is_typeArray_klass(), "should be type array");
2731 classloader2 = NULL;
2732 classpkg2 = NULL;
2733 }
2734
2735 // Same package is determined by comparing class loader
2736 // and package entries. Both must be the same. This rule
2737 // applies even to classes that are defined in the unnamed
2738 // package, they still must have the same class loader.
2739 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2740 return true;
2741 }
2742
2743 return false;
2744 }
2745
2746 // return true if this class and other_class are in the same package. Classloader
2747 // and classname information is enough to determine a class's package
2748 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2749 const Symbol* other_class_name) const {
2750 if (class_loader() != other_class_loader) {
2751 return false;
2752 }
2753 if (name()->fast_compare(other_class_name) == 0) {
2754 return true;
2755 }
2756
2757 {
2758 ResourceMark rm;
2759
2760 bool bad_class_name = false;
2761 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
2762 if (bad_class_name) {
2763 return false;
2764 }
2765 // Check that package_from_class_name() returns NULL, not "", if there is no package.
2766 assert(other_pkg == NULL || other_pkg->utf8_length() > 0, "package name is empty string");
2767
2768 const Symbol* const this_package_name =
2769 this->package() != NULL ? this->package()->name() : NULL;
2770
2771 if (this_package_name == NULL || other_pkg == NULL) {
2772 // One of the two doesn't have a package. Only return true if the other
2773 // one also doesn't have a package.
2774 return this_package_name == other_pkg;
2775 }
2776
2777 // Check if package is identical
2778 return this_package_name->fast_compare(other_pkg) == 0;
2779 }
2780 }
2781
2782 // Returns true iff super_method can be overridden by a method in targetclassname
2783 // See JLS 3rd edition 8.4.6.1
2784 // Assumes name-signature match
2785 // "this" is InstanceKlass of super_method which must exist
2786 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2787 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2788 // Private methods can not be overridden
2789 if (super_method->is_private()) {
2790 return false;
2791 }
2792 // If super method is accessible, then override
2793 if ((super_method->is_protected()) ||
2794 (super_method->is_public())) {
2795 return true;
2796 }
2797 // Package-private methods are not inherited outside of package
2798 assert(super_method->is_package_private(), "must be package private");
2799 return(is_same_class_package(targetclassloader(), targetclassname));
2800 }
2801
2802 // Only boot and platform class loaders can define classes in "java/" packages.
2803 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2804 ClassLoaderData* loader_data,
2805 TRAPS) {
2806 if (!loader_data->is_boot_class_loader_data() &&
2807 !loader_data->is_platform_class_loader_data() &&
2808 class_name != NULL) {
2809 ResourceMark rm(THREAD);
2810 char* name = class_name->as_C_string();
2811 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2812 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
2813 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2814 name = pkg_name->as_C_string();
2815 const char* class_loader_name = loader_data->loader_name_and_id();
2816 StringUtils::replace_no_expand(name, "/", ".");
2817 const char* msg_text1 = "Class loader (instance of): ";
2818 const char* msg_text2 = " tried to load prohibited package name: ";
2819 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2820 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2821 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2822 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2823 }
2824 }
2825 return;
2826 }
2827
2828 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2829 constantPoolHandle i_cp(THREAD, constants());
2830 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2831 int ioff = iter.inner_class_info_index();
2832 if (ioff != 0) {
2833 // Check to see if the name matches the class we're looking for
2834 // before attempting to find the class.
2835 if (i_cp->klass_name_at_matches(this, ioff)) {
2836 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2837 if (this == inner_klass) {
2838 *ooff = iter.outer_class_info_index();
2839 *noff = iter.inner_name_index();
2840 return true;
2841 }
2842 }
2843 }
2844 }
2845 return false;
2846 }
2847
2848 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2849 InstanceKlass* outer_klass = NULL;
2850 *inner_is_member = false;
2851 int ooff = 0, noff = 0;
2852 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2853 if (has_inner_classes_attr) {
2854 constantPoolHandle i_cp(THREAD, constants());
2855 if (ooff != 0) {
2856 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2857 outer_klass = InstanceKlass::cast(ok);
2858 *inner_is_member = true;
2859 }
2860 if (NULL == outer_klass) {
2861 // It may be unsafe anonymous; try for that.
2862 int encl_method_class_idx = enclosing_method_class_index();
2863 if (encl_method_class_idx != 0) {
2864 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2865 outer_klass = InstanceKlass::cast(ok);
2866 *inner_is_member = false;
2867 }
2868 }
2869 }
2870
2871 // If no inner class attribute found for this class.
2872 if (NULL == outer_klass) return NULL;
2873
2874 // Throws an exception if outer klass has not declared k as an inner klass
2875 // We need evidence that each klass knows about the other, or else
2876 // the system could allow a spoof of an inner class to gain access rights.
2877 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2878 return outer_klass;
2879 }
2880
2881 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2882 jint access = access_flags().as_int();
2883
2884 // But check if it happens to be member class.
2885 InnerClassesIterator iter(this);
2886 for (; !iter.done(); iter.next()) {
2887 int ioff = iter.inner_class_info_index();
2888 // Inner class attribute can be zero, skip it.
2889 // Strange but true: JVM spec. allows null inner class refs.
2890 if (ioff == 0) continue;
2891
2892 // only look at classes that are already loaded
2893 // since we are looking for the flags for our self.
2894 Symbol* inner_name = constants()->klass_name_at(ioff);
2895 if (name() == inner_name) {
2896 // This is really a member class.
2897 access = iter.inner_access_flags();
2898 break;
2899 }
2900 }
2901 // Remember to strip ACC_SUPER bit
2902 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2903 }
2904
2905 jint InstanceKlass::jvmti_class_status() const {
2906 jint result = 0;
2907
2908 if (is_linked()) {
2909 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2910 }
2911
2912 if (is_initialized()) {
2913 assert(is_linked(), "Class status is not consistent");
2914 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2915 }
2916 if (is_in_error_state()) {
2917 result |= JVMTI_CLASS_STATUS_ERROR;
2918 }
2919 return result;
2920 }
2921
2922 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2923 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2924 int method_table_offset_in_words = ioe->offset()/wordSize;
2925 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2926 / itableOffsetEntry::size();
2927
2928 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2929 // If the interface isn't implemented by the receiver class,
2930 // the VM should throw IncompatibleClassChangeError.
2931 if (cnt >= nof_interfaces) {
2932 ResourceMark rm(THREAD);
2933 stringStream ss;
2934 bool same_module = (module() == holder->module());
2935 ss.print("Receiver class %s does not implement "
2936 "the interface %s defining the method to be called "
2937 "(%s%s%s)",
2938 external_name(), holder->external_name(),
2939 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2940 (same_module) ? "" : "; ",
2941 (same_module) ? "" : holder->class_in_module_of_loader());
2942 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2943 }
2944
2945 Klass* ik = ioe->interface_klass();
2946 if (ik == holder) break;
2947 }
2948
2949 itableMethodEntry* ime = ioe->first_method_entry(this);
2950 Method* m = ime[index].method();
2951 if (m == NULL) {
2952 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2953 }
2954 return m;
2955 }
2956
2957
2958 #if INCLUDE_JVMTI
2959 // update default_methods for redefineclasses for methods that are
2960 // not yet in the vtable due to concurrent subclass define and superinterface
2961 // redefinition
2962 // Note: those in the vtable, should have been updated via adjust_method_entries
2963 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
2964 // search the default_methods for uses of either obsolete or EMCP methods
2965 if (default_methods() != NULL) {
2966 for (int index = 0; index < default_methods()->length(); index ++) {
2967 Method* old_method = default_methods()->at(index);
2968 if (old_method == NULL || !old_method->is_old()) {
2969 continue; // skip uninteresting entries
2970 }
2971 assert(!old_method->is_deleted(), "default methods may not be deleted");
2972 Method* new_method = old_method->get_new_method();
2973 default_methods()->at_put(index, new_method);
2974
2975 if (log_is_enabled(Info, redefine, class, update)) {
2976 ResourceMark rm;
2977 if (!(*trace_name_printed)) {
2978 log_info(redefine, class, update)
2979 ("adjust: klassname=%s default methods from name=%s",
2980 external_name(), old_method->method_holder()->external_name());
2981 *trace_name_printed = true;
2982 }
2983 log_debug(redefine, class, update, vtables)
2984 ("default method update: %s(%s) ",
2985 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2986 }
2987 }
2988 }
2989 }
2990 #endif // INCLUDE_JVMTI
2991
2992 // On-stack replacement stuff
2993 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2994 assert_lock_strong(CompiledMethod_lock);
2995 #ifndef PRODUCT
2996 if (TieredCompilation) {
2997 nmethod * prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
2998 assert(prev == NULL || !prev->is_in_use(),
2999 "redundunt OSR recompilation detected. memory leak in CodeCache!");
3000 }
3001 #endif
3002 // only one compilation can be active
3003 {
3004 assert(n->is_osr_method(), "wrong kind of nmethod");
3005 n->set_osr_link(osr_nmethods_head());
3006 set_osr_nmethods_head(n);
3007 // Raise the highest osr level if necessary
3008 if (TieredCompilation) {
3009 Method* m = n->method();
3010 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
3011 }
3012 }
3013
3014 // Get rid of the osr methods for the same bci that have lower levels.
3015 if (TieredCompilation) {
3016 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3017 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3018 if (inv != NULL && inv->is_in_use()) {
3019 inv->make_not_entrant();
3020 }
3021 }
3022 }
3023 }
3024
3025 // Remove osr nmethod from the list. Return true if found and removed.
3026 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3027 // This is a short non-blocking critical region, so the no safepoint check is ok.
3028 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock
3029 , Mutex::_no_safepoint_check_flag);
3030 assert(n->is_osr_method(), "wrong kind of nmethod");
3031 nmethod* last = NULL;
3032 nmethod* cur = osr_nmethods_head();
3033 int max_level = CompLevel_none; // Find the max comp level excluding n
3034 Method* m = n->method();
3035 // Search for match
3036 bool found = false;
3037 while(cur != NULL && cur != n) {
3038 if (TieredCompilation && m == cur->method()) {
3039 // Find max level before n
3040 max_level = MAX2(max_level, cur->comp_level());
3041 }
3042 last = cur;
3043 cur = cur->osr_link();
3044 }
3045 nmethod* next = NULL;
3046 if (cur == n) {
3047 found = true;
3048 next = cur->osr_link();
3049 if (last == NULL) {
3050 // Remove first element
3051 set_osr_nmethods_head(next);
3052 } else {
3053 last->set_osr_link(next);
3054 }
3055 }
3056 n->set_osr_link(NULL);
3057 if (TieredCompilation) {
3058 cur = next;
3059 while (cur != NULL) {
3060 // Find max level after n
3061 if (m == cur->method()) {
3062 max_level = MAX2(max_level, cur->comp_level());
3063 }
3064 cur = cur->osr_link();
3065 }
3066 m->set_highest_osr_comp_level(max_level);
3067 }
3068 return found;
3069 }
3070
3071 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3072 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3073 Mutex::_no_safepoint_check_flag);
3074 nmethod* osr = osr_nmethods_head();
3075 int found = 0;
3076 while (osr != NULL) {
3077 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3078 if (osr->method() == m) {
3079 osr->mark_for_deoptimization();
3080 found++;
3081 }
3082 osr = osr->osr_link();
3083 }
3084 return found;
3085 }
3086
3087 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3088 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3089 Mutex::_no_safepoint_check_flag);
3090 nmethod* osr = osr_nmethods_head();
3091 nmethod* best = NULL;
3092 while (osr != NULL) {
3093 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3094 // There can be a time when a c1 osr method exists but we are waiting
3095 // for a c2 version. When c2 completes its osr nmethod we will trash
3096 // the c1 version and only be able to find the c2 version. However
3097 // while we overflow in the c1 code at back branches we don't want to
3098 // try and switch to the same code as we are already running
3099
3100 if (osr->method() == m &&
3101 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3102 if (match_level) {
3103 if (osr->comp_level() == comp_level) {
3104 // Found a match - return it.
3105 return osr;
3106 }
3107 } else {
3108 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3109 if (osr->comp_level() == CompLevel_highest_tier) {
3110 // Found the best possible - return it.
3111 return osr;
3112 }
3113 best = osr;
3114 }
3115 }
3116 }
3117 osr = osr->osr_link();
3118 }
3119
3120 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set");
3121 if (best != NULL && best->comp_level() >= comp_level) {
3122 return best;
3123 }
3124 return NULL;
3125 }
3126
3127 // -----------------------------------------------------------------------------------------------------
3128 // Printing
3129
3130 #ifndef PRODUCT
3131
3132 #define BULLET " - "
3133
3134 static const char* state_names[] = {
3135 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3136 };
3137
3138 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3139 for (int i = 0; i < len; i++) {
3140 intptr_t e = start[i];
3141 st->print("%d : " INTPTR_FORMAT, i, e);
3142 if (MetaspaceObj::is_valid((Metadata*)e)) {
3143 st->print(" ");
3144 ((Metadata*)e)->print_value_on(st);
3145 }
3146 st->cr();
3147 }
3148 }
3149
3150 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3151 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3152 }
3153
3154 void InstanceKlass::print_on(outputStream* st) const {
3155 assert(is_klass(), "must be klass");
3156 Klass::print_on(st);
3157
3158 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3159 st->print(BULLET"klass size: %d", size()); st->cr();
3160 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3161 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3162 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3163 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3164 st->print(BULLET"sub: ");
3165 Klass* sub = subklass();
3166 int n;
3167 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3168 if (n < MaxSubklassPrintSize) {
3169 sub->print_value_on(st);
3170 st->print(" ");
3171 }
3172 }
3173 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3174 st->cr();
3175
3176 if (is_interface()) {
3177 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3178 if (nof_implementors() == 1) {
3179 st->print_cr(BULLET"implementor: ");
3180 st->print(" ");
3181 implementor()->print_value_on(st);
3182 st->cr();
3183 }
3184 }
3185
3186 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3187 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3188 if (Verbose || WizardMode) {
3189 Array<Method*>* method_array = methods();
3190 for (int i = 0; i < method_array->length(); i++) {
3191 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3192 }
3193 }
3194 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3195 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3196 if (Verbose && default_methods() != NULL) {
3197 Array<Method*>* method_array = default_methods();
3198 for (int i = 0; i < method_array->length(); i++) {
3199 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3200 }
3201 }
3202 if (default_vtable_indices() != NULL) {
3203 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3204 }
3205 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3206 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3207 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3208 if (class_loader_data() != NULL) {
3209 st->print(BULLET"class loader data: ");
3210 class_loader_data()->print_value_on(st);
3211 st->cr();
3212 }
3213 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3214 if (source_file_name() != NULL) {
3215 st->print(BULLET"source file: ");
3216 source_file_name()->print_value_on(st);
3217 st->cr();
3218 }
3219 if (source_debug_extension() != NULL) {
3220 st->print(BULLET"source debug extension: ");
3221 st->print("%s", source_debug_extension());
3222 st->cr();
3223 }
3224 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3225 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3226 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3227 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3228 {
3229 bool have_pv = false;
3230 // previous versions are linked together through the InstanceKlass
3231 for (InstanceKlass* pv_node = previous_versions();
3232 pv_node != NULL;
3233 pv_node = pv_node->previous_versions()) {
3234 if (!have_pv)
3235 st->print(BULLET"previous version: ");
3236 have_pv = true;
3237 pv_node->constants()->print_value_on(st);
3238 }
3239 if (have_pv) st->cr();
3240 }
3241
3242 if (generic_signature() != NULL) {
3243 st->print(BULLET"generic signature: ");
3244 generic_signature()->print_value_on(st);
3245 st->cr();
3246 }
3247 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3248 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3249 if (record_components() != NULL) {
3250 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3251 }
3252 if (java_mirror() != NULL) {
3253 st->print(BULLET"java mirror: ");
3254 java_mirror()->print_value_on(st);
3255 st->cr();
3256 } else {
3257 st->print_cr(BULLET"java mirror: NULL");
3258 }
3259 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3260 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3261 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3262 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3263 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3264 FieldPrinter print_static_field(st);
3265 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3266 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3267 FieldPrinter print_nonstatic_field(st);
3268 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3269 ik->do_nonstatic_fields(&print_nonstatic_field);
3270
3271 st->print(BULLET"non-static oop maps: ");
3272 OopMapBlock* map = start_of_nonstatic_oop_maps();
3273 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3274 while (map < end_map) {
3275 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3276 map++;
3277 }
3278 st->cr();
3279 }
3280
3281 #endif //PRODUCT
3282
3283 void InstanceKlass::print_value_on(outputStream* st) const {
3284 assert(is_klass(), "must be klass");
3285 if (Verbose || WizardMode) access_flags().print_on(st);
3286 name()->print_value_on(st);
3287 }
3288
3289 #ifndef PRODUCT
3290
3291 void FieldPrinter::do_field(fieldDescriptor* fd) {
3292 _st->print(BULLET);
3293 if (_obj == NULL) {
3294 fd->print_on(_st);
3295 _st->cr();
3296 } else {
3297 fd->print_on_for(_st, _obj);
3298 _st->cr();
3299 }
3300 }
3301
3302
3303 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3304 Klass::oop_print_on(obj, st);
3305
3306 if (this == SystemDictionary::String_klass()) {
3307 typeArrayOop value = java_lang_String::value(obj);
3308 juint length = java_lang_String::length(obj);
3309 if (value != NULL &&
3310 value->is_typeArray() &&
3311 length <= (juint) value->length()) {
3312 st->print(BULLET"string: ");
3313 java_lang_String::print(obj, st);
3314 st->cr();
3315 if (!WizardMode) return; // that is enough
3316 }
3317 }
3318
3319 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3320 FieldPrinter print_field(st, obj);
3321 do_nonstatic_fields(&print_field);
3322
3323 if (this == SystemDictionary::Class_klass()) {
3324 st->print(BULLET"signature: ");
3325 java_lang_Class::print_signature(obj, st);
3326 st->cr();
3327 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3328 st->print(BULLET"fake entry for mirror: ");
3329 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3330 st->cr();
3331 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3332 st->print(BULLET"fake entry for array: ");
3333 Metadata::print_value_on_maybe_null(st, array_klass);
3334 st->cr();
3335 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3336 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3337 Klass* real_klass = java_lang_Class::as_Klass(obj);
3338 if (real_klass != NULL && real_klass->is_instance_klass()) {
3339 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3340 }
3341 } else if (this == SystemDictionary::MethodType_klass()) {
3342 st->print(BULLET"signature: ");
3343 java_lang_invoke_MethodType::print_signature(obj, st);
3344 st->cr();
3345 }
3346 }
3347
3348 bool InstanceKlass::verify_itable_index(int i) {
3349 int method_count = klassItable::method_count_for_interface(this);
3350 assert(i >= 0 && i < method_count, "index out of bounds");
3351 return true;
3352 }
3353
3354 #endif //PRODUCT
3355
3356 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3357 st->print("a ");
3358 name()->print_value_on(st);
3359 obj->print_address_on(st);
3360 if (this == SystemDictionary::String_klass()
3361 && java_lang_String::value(obj) != NULL) {
3362 ResourceMark rm;
3363 int len = java_lang_String::length(obj);
3364 int plen = (len < 24 ? len : 12);
3365 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3366 st->print(" = \"%s\"", str);
3367 if (len > plen)
3368 st->print("...[%d]", len);
3369 } else if (this == SystemDictionary::Class_klass()) {
3370 Klass* k = java_lang_Class::as_Klass(obj);
3371 st->print(" = ");
3372 if (k != NULL) {
3373 k->print_value_on(st);
3374 } else {
3375 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3376 st->print("%s", tname ? tname : "type?");
3377 }
3378 } else if (this == SystemDictionary::MethodType_klass()) {
3379 st->print(" = ");
3380 java_lang_invoke_MethodType::print_signature(obj, st);
3381 } else if (java_lang_boxing_object::is_instance(obj)) {
3382 st->print(" = ");
3383 java_lang_boxing_object::print(obj, st);
3384 } else if (this == SystemDictionary::LambdaForm_klass()) {
3385 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3386 if (vmentry != NULL) {
3387 st->print(" => ");
3388 vmentry->print_value_on(st);
3389 }
3390 } else if (this == SystemDictionary::MemberName_klass()) {
3391 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3392 if (vmtarget != NULL) {
3393 st->print(" = ");
3394 vmtarget->print_value_on(st);
3395 } else {
3396 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3397 st->print(".");
3398 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3399 }
3400 }
3401 }
3402
3403 const char* InstanceKlass::internal_name() const {
3404 return external_name();
3405 }
3406
3407 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3408 const char* module_name,
3409 const ClassFileStream* cfs) const {
3410 if (!log_is_enabled(Info, class, load)) {
3411 return;
3412 }
3413
3414 ResourceMark rm;
3415 LogMessage(class, load) msg;
3416 stringStream info_stream;
3417
3418 // Name and class hierarchy info
3419 info_stream.print("%s", external_name());
3420
3421 // Source
3422 if (cfs != NULL) {
3423 if (cfs->source() != NULL) {
3424 if (module_name != NULL) {
3425 // When the boot loader created the stream, it didn't know the module name
3426 // yet. Let's format it now.
3427 if (cfs->from_boot_loader_modules_image()) {
3428 info_stream.print(" source: jrt:/%s", module_name);
3429 } else {
3430 info_stream.print(" source: %s", cfs->source());
3431 }
3432 } else {
3433 info_stream.print(" source: %s", cfs->source());
3434 }
3435 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3436 Thread* THREAD = Thread::current();
3437 Klass* caller =
3438 THREAD->is_Java_thread()
3439 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3440 : NULL;
3441 // caller can be NULL, for example, during a JVMTI VM_Init hook
3442 if (caller != NULL) {
3443 info_stream.print(" source: instance of %s", caller->external_name());
3444 } else {
3445 // source is unknown
3446 }
3447 } else {
3448 oop class_loader = loader_data->class_loader();
3449 info_stream.print(" source: %s", class_loader->klass()->external_name());
3450 }
3451 } else {
3452 assert(this->is_shared(), "must be");
3453 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3454 info_stream.print(" source: shared objects file (top)");
3455 } else {
3456 info_stream.print(" source: shared objects file");
3457 }
3458 }
3459
3460 msg.info("%s", info_stream.as_string());
3461
3462 if (log_is_enabled(Debug, class, load)) {
3463 stringStream debug_stream;
3464
3465 // Class hierarchy info
3466 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3467 p2i(this), p2i(superklass()));
3468
3469 // Interfaces
3470 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3471 debug_stream.print(" interfaces:");
3472 int length = local_interfaces()->length();
3473 for (int i = 0; i < length; i++) {
3474 debug_stream.print(" " INTPTR_FORMAT,
3475 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3476 }
3477 }
3478
3479 // Class loader
3480 debug_stream.print(" loader: [");
3481 loader_data->print_value_on(&debug_stream);
3482 debug_stream.print("]");
3483
3484 // Classfile checksum
3485 if (cfs) {
3486 debug_stream.print(" bytes: %d checksum: %08x",
3487 cfs->length(),
3488 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3489 cfs->length()));
3490 }
3491
3492 msg.debug("%s", debug_stream.as_string());
3493 }
3494 }
3495
3496 // Verification
3497
3498 class VerifyFieldClosure: public BasicOopIterateClosure {
3499 protected:
3500 template <class T> void do_oop_work(T* p) {
3501 oop obj = RawAccess<>::oop_load(p);
3502 if (!oopDesc::is_oop_or_null(obj)) {
3503 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3504 Universe::print_on(tty);
3505 guarantee(false, "boom");
3506 }
3507 }
3508 public:
3509 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3510 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3511 };
3512
3513 void InstanceKlass::verify_on(outputStream* st) {
3514 #ifndef PRODUCT
3515 // Avoid redundant verifies, this really should be in product.
3516 if (_verify_count == Universe::verify_count()) return;
3517 _verify_count = Universe::verify_count();
3518 #endif
3519
3520 // Verify Klass
3521 Klass::verify_on(st);
3522
3523 // Verify that klass is present in ClassLoaderData
3524 guarantee(class_loader_data()->contains_klass(this),
3525 "this class isn't found in class loader data");
3526
3527 // Verify vtables
3528 if (is_linked()) {
3529 // $$$ This used to be done only for m/s collections. Doing it
3530 // always seemed a valid generalization. (DLD -- 6/00)
3531 vtable().verify(st);
3532 }
3533
3534 // Verify first subklass
3535 if (subklass() != NULL) {
3536 guarantee(subklass()->is_klass(), "should be klass");
3537 }
3538
3539 // Verify siblings
3540 Klass* super = this->super();
3541 Klass* sib = next_sibling();
3542 if (sib != NULL) {
3543 if (sib == this) {
3544 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3545 }
3546
3547 guarantee(sib->is_klass(), "should be klass");
3548 guarantee(sib->super() == super, "siblings should have same superklass");
3549 }
3550
3551 // Verify local interfaces
3552 if (local_interfaces()) {
3553 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3554 for (int j = 0; j < local_interfaces->length(); j++) {
3555 InstanceKlass* e = local_interfaces->at(j);
3556 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3557 }
3558 }
3559
3560 // Verify transitive interfaces
3561 if (transitive_interfaces() != NULL) {
3562 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3563 for (int j = 0; j < transitive_interfaces->length(); j++) {
3564 InstanceKlass* e = transitive_interfaces->at(j);
3565 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3566 }
3567 }
3568
3569 // Verify methods
3570 if (methods() != NULL) {
3571 Array<Method*>* methods = this->methods();
3572 for (int j = 0; j < methods->length(); j++) {
3573 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3574 }
3575 for (int j = 0; j < methods->length() - 1; j++) {
3576 Method* m1 = methods->at(j);
3577 Method* m2 = methods->at(j + 1);
3578 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3579 }
3580 }
3581
3582 // Verify method ordering
3583 if (method_ordering() != NULL) {
3584 Array<int>* method_ordering = this->method_ordering();
3585 int length = method_ordering->length();
3586 if (JvmtiExport::can_maintain_original_method_order() ||
3587 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
3588 guarantee(length == methods()->length(), "invalid method ordering length");
3589 jlong sum = 0;
3590 for (int j = 0; j < length; j++) {
3591 int original_index = method_ordering->at(j);
3592 guarantee(original_index >= 0, "invalid method ordering index");
3593 guarantee(original_index < length, "invalid method ordering index");
3594 sum += original_index;
3595 }
3596 // Verify sum of indices 0,1,...,length-1
3597 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3598 } else {
3599 guarantee(length == 0, "invalid method ordering length");
3600 }
3601 }
3602
3603 // Verify default methods
3604 if (default_methods() != NULL) {
3605 Array<Method*>* methods = this->default_methods();
3606 for (int j = 0; j < methods->length(); j++) {
3607 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3608 }
3609 for (int j = 0; j < methods->length() - 1; j++) {
3610 Method* m1 = methods->at(j);
3611 Method* m2 = methods->at(j + 1);
3612 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3613 }
3614 }
3615
3616 // Verify JNI static field identifiers
3617 if (jni_ids() != NULL) {
3618 jni_ids()->verify(this);
3619 }
3620
3621 // Verify other fields
3622 if (array_klasses() != NULL) {
3623 guarantee(array_klasses()->is_klass(), "should be klass");
3624 }
3625 if (constants() != NULL) {
3626 guarantee(constants()->is_constantPool(), "should be constant pool");
3627 }
3628 const Klass* anonymous_host = unsafe_anonymous_host();
3629 if (anonymous_host != NULL) {
3630 guarantee(anonymous_host->is_klass(), "should be klass");
3631 }
3632 }
3633
3634 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3635 Klass::oop_verify_on(obj, st);
3636 VerifyFieldClosure blk;
3637 obj->oop_iterate(&blk);
3638 }
3639
3640
3641 // JNIid class for jfieldIDs only
3642 // Note to reviewers:
3643 // These JNI functions are just moved over to column 1 and not changed
3644 // in the compressed oops workspace.
3645 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3646 _holder = holder;
3647 _offset = offset;
3648 _next = next;
3649 debug_only(_is_static_field_id = false;)
3650 }
3651
3652
3653 JNIid* JNIid::find(int offset) {
3654 JNIid* current = this;
3655 while (current != NULL) {
3656 if (current->offset() == offset) return current;
3657 current = current->next();
3658 }
3659 return NULL;
3660 }
3661
3662 void JNIid::deallocate(JNIid* current) {
3663 while (current != NULL) {
3664 JNIid* next = current->next();
3665 delete current;
3666 current = next;
3667 }
3668 }
3669
3670
3671 void JNIid::verify(Klass* holder) {
3672 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3673 int end_field_offset;
3674 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3675
3676 JNIid* current = this;
3677 while (current != NULL) {
3678 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3679 #ifdef ASSERT
3680 int o = current->offset();
3681 if (current->is_static_field_id()) {
3682 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3683 }
3684 #endif
3685 current = current->next();
3686 }
3687 }
3688
3689 void InstanceKlass::set_init_state(ClassState state) {
3690 #ifdef ASSERT
3691 bool good_state = is_shared() ? (_init_state <= state)
3692 : (_init_state < state);
3693 assert(good_state || state == allocated, "illegal state transition");
3694 #endif
3695 assert(_init_thread == NULL, "should be cleared before state change");
3696 _init_state = (u1)state;
3697 }
3698
3699 #if INCLUDE_JVMTI
3700
3701 // RedefineClasses() support for previous versions
3702
3703 // Globally, there is at least one previous version of a class to walk
3704 // during class unloading, which is saved because old methods in the class
3705 // are still running. Otherwise the previous version list is cleaned up.
3706 bool InstanceKlass::_has_previous_versions = false;
3707
3708 // Returns true if there are previous versions of a class for class
3709 // unloading only. Also resets the flag to false. purge_previous_version
3710 // will set the flag to true if there are any left, i.e., if there's any
3711 // work to do for next time. This is to avoid the expensive code cache
3712 // walk in CLDG::clean_deallocate_lists().
3713 bool InstanceKlass::has_previous_versions_and_reset() {
3714 bool ret = _has_previous_versions;
3715 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3716 ret ? "true" : "false");
3717 _has_previous_versions = false;
3718 return ret;
3719 }
3720
3721 // Purge previous versions before adding new previous versions of the class and
3722 // during class unloading.
3723 void InstanceKlass::purge_previous_version_list() {
3724 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3725 assert(has_been_redefined(), "Should only be called for main class");
3726
3727 // Quick exit.
3728 if (previous_versions() == NULL) {
3729 return;
3730 }
3731
3732 // This klass has previous versions so see what we can cleanup
3733 // while it is safe to do so.
3734
3735 int deleted_count = 0; // leave debugging breadcrumbs
3736 int live_count = 0;
3737 ClassLoaderData* loader_data = class_loader_data();
3738 assert(loader_data != NULL, "should never be null");
3739
3740 ResourceMark rm;
3741 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3742
3743 // previous versions are linked together through the InstanceKlass
3744 InstanceKlass* pv_node = previous_versions();
3745 InstanceKlass* last = this;
3746 int version = 0;
3747
3748 // check the previous versions list
3749 for (; pv_node != NULL; ) {
3750
3751 ConstantPool* pvcp = pv_node->constants();
3752 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3753
3754 if (!pvcp->on_stack()) {
3755 // If the constant pool isn't on stack, none of the methods
3756 // are executing. Unlink this previous_version.
3757 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3758 // so will be deallocated during the next phase of class unloading.
3759 log_trace(redefine, class, iklass, purge)
3760 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3761 // For debugging purposes.
3762 pv_node->set_is_scratch_class();
3763 // Unlink from previous version list.
3764 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3765 InstanceKlass* next = pv_node->previous_versions();
3766 pv_node->link_previous_versions(NULL); // point next to NULL
3767 last->link_previous_versions(next);
3768 // Add to the deallocate list after unlinking
3769 loader_data->add_to_deallocate_list(pv_node);
3770 pv_node = next;
3771 deleted_count++;
3772 version++;
3773 continue;
3774 } else {
3775 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3776 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3777 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3778 live_count++;
3779 // found a previous version for next time we do class unloading
3780 _has_previous_versions = true;
3781 }
3782
3783 // At least one method is live in this previous version.
3784 // Reset dead EMCP methods not to get breakpoints.
3785 // All methods are deallocated when all of the methods for this class are no
3786 // longer running.
3787 Array<Method*>* method_refs = pv_node->methods();
3788 if (method_refs != NULL) {
3789 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3790 for (int j = 0; j < method_refs->length(); j++) {
3791 Method* method = method_refs->at(j);
3792
3793 if (!method->on_stack()) {
3794 // no breakpoints for non-running methods
3795 if (method->is_running_emcp()) {
3796 method->set_running_emcp(false);
3797 }
3798 } else {
3799 assert (method->is_obsolete() || method->is_running_emcp(),
3800 "emcp method cannot run after emcp bit is cleared");
3801 log_trace(redefine, class, iklass, purge)
3802 ("purge: %s(%s): prev method @%d in version @%d is alive",
3803 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3804 }
3805 }
3806 }
3807 // next previous version
3808 last = pv_node;
3809 pv_node = pv_node->previous_versions();
3810 version++;
3811 }
3812 log_trace(redefine, class, iklass, purge)
3813 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3814 }
3815
3816 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3817 int emcp_method_count) {
3818 int obsolete_method_count = old_methods->length() - emcp_method_count;
3819
3820 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3821 _previous_versions != NULL) {
3822 // We have a mix of obsolete and EMCP methods so we have to
3823 // clear out any matching EMCP method entries the hard way.
3824 int local_count = 0;
3825 for (int i = 0; i < old_methods->length(); i++) {
3826 Method* old_method = old_methods->at(i);
3827 if (old_method->is_obsolete()) {
3828 // only obsolete methods are interesting
3829 Symbol* m_name = old_method->name();
3830 Symbol* m_signature = old_method->signature();
3831
3832 // previous versions are linked together through the InstanceKlass
3833 int j = 0;
3834 for (InstanceKlass* prev_version = _previous_versions;
3835 prev_version != NULL;
3836 prev_version = prev_version->previous_versions(), j++) {
3837
3838 Array<Method*>* method_refs = prev_version->methods();
3839 for (int k = 0; k < method_refs->length(); k++) {
3840 Method* method = method_refs->at(k);
3841
3842 if (!method->is_obsolete() &&
3843 method->name() == m_name &&
3844 method->signature() == m_signature) {
3845 // The current RedefineClasses() call has made all EMCP
3846 // versions of this method obsolete so mark it as obsolete
3847 log_trace(redefine, class, iklass, add)
3848 ("%s(%s): flush obsolete method @%d in version @%d",
3849 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3850
3851 method->set_is_obsolete();
3852 break;
3853 }
3854 }
3855
3856 // The previous loop may not find a matching EMCP method, but
3857 // that doesn't mean that we can optimize and not go any
3858 // further back in the PreviousVersion generations. The EMCP
3859 // method for this generation could have already been made obsolete,
3860 // but there still may be an older EMCP method that has not
3861 // been made obsolete.
3862 }
3863
3864 if (++local_count >= obsolete_method_count) {
3865 // no more obsolete methods so bail out now
3866 break;
3867 }
3868 }
3869 }
3870 }
3871 }
3872
3873 // Save the scratch_class as the previous version if any of the methods are running.
3874 // The previous_versions are used to set breakpoints in EMCP methods and they are
3875 // also used to clean MethodData links to redefined methods that are no longer running.
3876 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3877 int emcp_method_count) {
3878 assert(Thread::current()->is_VM_thread(),
3879 "only VMThread can add previous versions");
3880
3881 ResourceMark rm;
3882 log_trace(redefine, class, iklass, add)
3883 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3884
3885 // Clean out old previous versions for this class
3886 purge_previous_version_list();
3887
3888 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3889 // a previous redefinition may be made obsolete by this redefinition.
3890 Array<Method*>* old_methods = scratch_class->methods();
3891 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3892
3893 // If the constant pool for this previous version of the class
3894 // is not marked as being on the stack, then none of the methods
3895 // in this previous version of the class are on the stack so
3896 // we don't need to add this as a previous version.
3897 ConstantPool* cp_ref = scratch_class->constants();
3898 if (!cp_ref->on_stack()) {
3899 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3900 // For debugging purposes.
3901 scratch_class->set_is_scratch_class();
3902 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3903 return;
3904 }
3905
3906 if (emcp_method_count != 0) {
3907 // At least one method is still running, check for EMCP methods
3908 for (int i = 0; i < old_methods->length(); i++) {
3909 Method* old_method = old_methods->at(i);
3910 if (!old_method->is_obsolete() && old_method->on_stack()) {
3911 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3912 // we can add breakpoints for it.
3913
3914 // We set the method->on_stack bit during safepoints for class redefinition
3915 // and use this bit to set the is_running_emcp bit.
3916 // After the safepoint, the on_stack bit is cleared and the running emcp
3917 // method may exit. If so, we would set a breakpoint in a method that
3918 // is never reached, but this won't be noticeable to the programmer.
3919 old_method->set_running_emcp(true);
3920 log_trace(redefine, class, iklass, add)
3921 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3922 } else if (!old_method->is_obsolete()) {
3923 log_trace(redefine, class, iklass, add)
3924 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3925 }
3926 }
3927 }
3928
3929 // Add previous version if any methods are still running.
3930 // Set has_previous_version flag for processing during class unloading.
3931 _has_previous_versions = true;
3932 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3933 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3934 scratch_class->link_previous_versions(previous_versions());
3935 link_previous_versions(scratch_class);
3936 } // end add_previous_version()
3937
3938 #endif // INCLUDE_JVMTI
3939
3940 Method* InstanceKlass::method_with_idnum(int idnum) {
3941 Method* m = NULL;
3942 if (idnum < methods()->length()) {
3943 m = methods()->at(idnum);
3944 }
3945 if (m == NULL || m->method_idnum() != idnum) {
3946 for (int index = 0; index < methods()->length(); ++index) {
3947 m = methods()->at(index);
3948 if (m->method_idnum() == idnum) {
3949 return m;
3950 }
3951 }
3952 // None found, return null for the caller to handle.
3953 return NULL;
3954 }
3955 return m;
3956 }
3957
3958
3959 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3960 if (idnum >= methods()->length()) {
3961 return NULL;
3962 }
3963 Method* m = methods()->at(idnum);
3964 if (m != NULL && m->orig_method_idnum() == idnum) {
3965 return m;
3966 }
3967 // Obsolete method idnum does not match the original idnum
3968 for (int index = 0; index < methods()->length(); ++index) {
3969 m = methods()->at(index);
3970 if (m->orig_method_idnum() == idnum) {
3971 return m;
3972 }
3973 }
3974 // None found, return null for the caller to handle.
3975 return NULL;
3976 }
3977
3978
3979 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3980 InstanceKlass* holder = get_klass_version(version);
3981 if (holder == NULL) {
3982 return NULL; // The version of klass is gone, no method is found
3983 }
3984 Method* method = holder->method_with_orig_idnum(idnum);
3985 return method;
3986 }
3987
3988 #if INCLUDE_JVMTI
3989 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3990 return _cached_class_file;
3991 }
3992
3993 jint InstanceKlass::get_cached_class_file_len() {
3994 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3995 }
3996
3997 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3998 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3999 }
4000 #endif