1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/verifier.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/dependencyContext.hpp"
39 #include "compiler/compileBroker.hpp"
40 #include "gc/shared/collectedHeap.inline.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/heapInspection.hpp"
49 #include "memory/iterator.inline.hpp"
50 #include "memory/metadataFactory.hpp"
51 #include "memory/metaspaceClosure.hpp"
52 #include "memory/metaspaceShared.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "oops/fieldStreams.hpp"
56 #include "oops/instanceClassLoaderKlass.hpp"
57 #include "oops/instanceKlass.inline.hpp"
58 #include "oops/instanceMirrorKlass.hpp"
59 #include "oops/instanceOop.hpp"
60 #include "oops/klass.inline.hpp"
61 #include "oops/method.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.inline.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83 #if INCLUDE_JFR
84 #include "jfr/jfrEvents.hpp"
85 #endif
86
87
88 #ifdef DTRACE_ENABLED
89
90
91 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
92 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
93 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
94 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
95 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
96 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
97 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
98 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
99 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
100 { \
101 char* data = NULL; \
102 int len = 0; \
103 Symbol* clss_name = name(); \
104 if (clss_name != NULL) { \
105 data = (char*)clss_name->bytes(); \
106 len = clss_name->utf8_length(); \
107 } \
108 HOTSPOT_CLASS_INITIALIZATION_##type( \
109 data, len, (void*)class_loader(), thread_type); \
110 }
111
112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
113 { \
114 char* data = NULL; \
115 int len = 0; \
116 Symbol* clss_name = name(); \
117 if (clss_name != NULL) { \
118 data = (char*)clss_name->bytes(); \
119 len = clss_name->utf8_length(); \
120 } \
121 HOTSPOT_CLASS_INITIALIZATION_##type( \
122 data, len, (void*)class_loader(), thread_type, wait); \
123 }
124
125 #else // ndef DTRACE_ENABLED
126
127 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
128 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
129
130 #endif // ndef DTRACE_ENABLED
131
132 static inline bool is_class_loader(const Symbol* class_name,
133 const ClassFileParser& parser) {
134 assert(class_name != NULL, "invariant");
135
136 if (class_name == vmSymbols::java_lang_ClassLoader()) {
137 return true;
138 }
139
140 if (SystemDictionary::ClassLoader_klass_loaded()) {
141 const Klass* const super_klass = parser.super_klass();
142 if (super_klass != NULL) {
143 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
144 return true;
145 }
146 }
147 }
148 return false;
149 }
150
151 // called to verify that k is a member of this nest
152 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
153 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
154 if (log_is_enabled(Trace, class, nestmates)) {
155 ResourceMark rm(THREAD);
156 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
157 k->external_name(), this->external_name());
158 }
159 return false;
160 }
161
162 if (log_is_enabled(Trace, class, nestmates)) {
163 ResourceMark rm(THREAD);
164 log_trace(class, nestmates)("Checking nest membership of %s in %s",
165 k->external_name(), this->external_name());
166 }
167
168 // Check for a resolved cp entry , else fall back to a name check.
169 // We don't want to resolve any class other than the one being checked.
170 for (int i = 0; i < _nest_members->length(); i++) {
171 int cp_index = _nest_members->at(i);
172 if (_constants->tag_at(cp_index).is_klass()) {
173 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
174 if (k2 == k) {
175 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
176 return true;
177 }
178 }
179 else {
180 Symbol* name = _constants->klass_name_at(cp_index);
181 if (name == k->name()) {
182 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
183
184 // names match so check actual klass - this may trigger class loading if
185 // it doesn't match (but that should be impossible)
186 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
187 if (k2 == k) {
188 log_trace(class, nestmates)("- class is listed as a nest member");
189 return true;
190 }
191 else {
192 // same name but different klass!
193 log_trace(class, nestmates)(" - klass comparison failed!");
194 // can't have two names the same, so we're done
195 return false;
196 }
197 }
198 }
199 }
200 log_trace(class, nestmates)("- class is NOT a nest member!");
201 return false;
202 }
203
204 // Return nest-host class, resolving, validating and saving it if needed.
205 // In cases where this is called from a thread that can not do classloading
206 // (such as a native JIT thread) then we simply return NULL, which in turn
207 // causes the access check to return false. Such code will retry the access
208 // from a more suitable environment later.
209 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
210 InstanceKlass* nest_host_k = _nest_host;
211 if (nest_host_k == NULL) {
212 // need to resolve and save our nest-host class. This could be attempted
213 // concurrently but as the result is idempotent and we don't use the class
214 // then we do not need any synchronization beyond what is implicitly used
215 // during class loading.
216 if (_nest_host_index != 0) { // we have a real nest_host
217 // Before trying to resolve check if we're in a suitable context
218 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
219 if (log_is_enabled(Trace, class, nestmates)) {
220 ResourceMark rm(THREAD);
221 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
222 this->external_name());
223 }
224 return NULL;
225 }
226
227 if (log_is_enabled(Trace, class, nestmates)) {
228 ResourceMark rm(THREAD);
229 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
230 this->external_name(),
231 _constants->klass_name_at(_nest_host_index)->as_C_string());
232 }
233
234 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
235 if (HAS_PENDING_EXCEPTION) {
236 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
237 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
238 // throw a new CDNFE with the original as its cause, and a clear msg
239 ResourceMark rm(THREAD);
240 char buf[200];
241 CLEAR_PENDING_EXCEPTION;
242 jio_snprintf(buf, sizeof(buf),
243 "Unable to load nest-host class (%s) of %s",
244 _constants->klass_name_at(_nest_host_index)->as_C_string(),
245 this->external_name());
246 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
247 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
248 }
249 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
250 return NULL;
251 }
252
253 // A valid nest-host is an instance class in the current package that lists this
254 // class as a nest member. If any of these conditions are not met we post the
255 // requested exception type (if any) and return NULL
256
257 const char* error = NULL;
258
259 // JVMS 5.4.4 indicates package check comes first
260 if (is_same_class_package(k)) {
261
262 // Now check actual membership. We can't be a member if our "host" is
263 // not an instance class.
264 if (k->is_instance_klass()) {
265 nest_host_k = InstanceKlass::cast(k);
266
267 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
268 if (is_member) {
269 // save resolved nest-host value
270 _nest_host = nest_host_k;
271
272 if (log_is_enabled(Trace, class, nestmates)) {
273 ResourceMark rm(THREAD);
274 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
275 this->external_name(), k->external_name());
276 }
277 return nest_host_k;
278 }
279 }
280 error = "current type is not listed as a nest member";
281 } else {
282 error = "types are in different packages";
283 }
284
285 if (log_is_enabled(Trace, class, nestmates)) {
286 ResourceMark rm(THREAD);
287 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
288 this->external_name(),
289 k->external_name(),
290 error);
291 }
292
293 if (validationException != NULL) {
294 ResourceMark rm(THREAD);
295 Exceptions::fthrow(THREAD_AND_LOCATION,
296 validationException,
297 "Type %s is not a nest member of %s: %s",
298 this->external_name(),
299 k->external_name(),
300 error
301 );
302 }
303 return NULL;
304 } else {
305 if (log_is_enabled(Trace, class, nestmates)) {
306 ResourceMark rm(THREAD);
307 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
308 this->external_name());
309 }
310 // save resolved nest-host value
311 return (_nest_host = this);
312 }
313 }
314 return nest_host_k;
315 }
316
317 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
318 // or we are k's nest_host - all of which is covered by comparing the two
319 // resolved_nest_hosts
320 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
321
322 assert(this != k, "this should be handled by higher-level code");
323
324 // Per JVMS 5.4.4 we first resolve and validate the current class, then
325 // the target class k. Resolution exceptions will be passed on by upper
326 // layers. IncompatibleClassChangeErrors from membership validation failures
327 // will also be passed through.
328
329 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
330 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
331 if (cur_host == NULL) {
332 return false;
333 }
334
335 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
336 if (k_nest_host == NULL) {
337 return false;
338 }
339
340 bool access = (cur_host == k_nest_host);
341
342 if (log_is_enabled(Trace, class, nestmates)) {
343 ResourceMark rm(THREAD);
344 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
345 this->external_name(),
346 access ? "" : "NOT ",
347 k->external_name());
348 }
349
350 return access;
351 }
352
353 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
354 const int size = InstanceKlass::size(parser.vtable_size(),
355 parser.itable_size(),
356 nonstatic_oop_map_size(parser.total_oop_map_count()),
357 parser.is_interface(),
358 parser.is_unsafe_anonymous(),
359 should_store_fingerprint(parser.is_unsafe_anonymous()));
360
361 const Symbol* const class_name = parser.class_name();
362 assert(class_name != NULL, "invariant");
363 ClassLoaderData* loader_data = parser.loader_data();
364 assert(loader_data != NULL, "invariant");
365
366 InstanceKlass* ik;
367
368 // Allocation
369 if (REF_NONE == parser.reference_type()) {
370 if (class_name == vmSymbols::java_lang_Class()) {
371 // mirror
372 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
373 }
374 else if (is_class_loader(class_name, parser)) {
375 // class loader
376 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
377 } else {
378 // normal
379 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
380 }
381 } else {
382 // reference
383 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
384 }
385
386 // Check for pending exception before adding to the loader data and incrementing
387 // class count. Can get OOM here.
388 if (HAS_PENDING_EXCEPTION) {
389 return NULL;
390 }
391
392 return ik;
393 }
394
395
396 // copy method ordering from resource area to Metaspace
397 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
398 if (m != NULL) {
399 // allocate a new array and copy contents (memcpy?)
400 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
401 for (int i = 0; i < m->length(); i++) {
402 _method_ordering->at_put(i, m->at(i));
403 }
404 } else {
405 _method_ordering = Universe::the_empty_int_array();
406 }
407 }
408
409 // create a new array of vtable_indices for default methods
410 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
411 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
412 assert(default_vtable_indices() == NULL, "only create once");
413 set_default_vtable_indices(vtable_indices);
414 return vtable_indices;
415 }
416
417 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
418 Klass(id),
419 _nest_members(NULL),
420 _nest_host_index(0),
421 _nest_host(NULL),
422 _static_field_size(parser.static_field_size()),
423 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
424 _itable_len(parser.itable_size()),
425 _reference_type(parser.reference_type()) {
426 set_vtable_length(parser.vtable_size());
427 set_kind(kind);
428 set_access_flags(parser.access_flags());
429 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
430 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
431 false));
432
433 assert(NULL == _methods, "underlying memory not zeroed?");
434 assert(is_instance_klass(), "is layout incorrect?");
435 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
436 }
437
438 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
439 Array<Method*>* methods) {
440 if (methods != NULL && methods != Universe::the_empty_method_array() &&
441 !methods->is_shared()) {
442 for (int i = 0; i < methods->length(); i++) {
443 Method* method = methods->at(i);
444 if (method == NULL) continue; // maybe null if error processing
445 // Only want to delete methods that are not executing for RedefineClasses.
446 // The previous version will point to them so they're not totally dangling
447 assert (!method->on_stack(), "shouldn't be called with methods on stack");
448 MetadataFactory::free_metadata(loader_data, method);
449 }
450 MetadataFactory::free_array<Method*>(loader_data, methods);
451 }
452 }
453
454 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
455 const Klass* super_klass,
456 Array<InstanceKlass*>* local_interfaces,
457 Array<InstanceKlass*>* transitive_interfaces) {
458 // Only deallocate transitive interfaces if not empty, same as super class
459 // or same as local interfaces. See code in parseClassFile.
460 Array<InstanceKlass*>* ti = transitive_interfaces;
461 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
462 // check that the interfaces don't come from super class
463 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
464 InstanceKlass::cast(super_klass)->transitive_interfaces();
465 if (ti != sti && ti != NULL && !ti->is_shared()) {
466 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
467 }
468 }
469
470 // local interfaces can be empty
471 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
472 local_interfaces != NULL && !local_interfaces->is_shared()) {
473 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
474 }
475 }
476
477 // This function deallocates the metadata and C heap pointers that the
478 // InstanceKlass points to.
479 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
480
481 // Orphan the mirror first, CMS thinks it's still live.
482 if (java_mirror() != NULL) {
483 java_lang_Class::set_klass(java_mirror(), NULL);
484 }
485
486 // Also remove mirror from handles
487 loader_data->remove_handle(_java_mirror);
488
489 // Need to take this class off the class loader data list.
490 loader_data->remove_class(this);
491
492 // The array_klass for this class is created later, after error handling.
493 // For class redefinition, we keep the original class so this scratch class
494 // doesn't have an array class. Either way, assert that there is nothing
495 // to deallocate.
496 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
497
498 // Release C heap allocated data that this might point to, which includes
499 // reference counting symbol names.
500 release_C_heap_structures();
501
502 deallocate_methods(loader_data, methods());
503 set_methods(NULL);
504
505 if (method_ordering() != NULL &&
506 method_ordering() != Universe::the_empty_int_array() &&
507 !method_ordering()->is_shared()) {
508 MetadataFactory::free_array<int>(loader_data, method_ordering());
509 }
510 set_method_ordering(NULL);
511
512 // default methods can be empty
513 if (default_methods() != NULL &&
514 default_methods() != Universe::the_empty_method_array() &&
515 !default_methods()->is_shared()) {
516 MetadataFactory::free_array<Method*>(loader_data, default_methods());
517 }
518 // Do NOT deallocate the default methods, they are owned by superinterfaces.
519 set_default_methods(NULL);
520
521 // default methods vtable indices can be empty
522 if (default_vtable_indices() != NULL &&
523 !default_vtable_indices()->is_shared()) {
524 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
525 }
526 set_default_vtable_indices(NULL);
527
528
529 // This array is in Klass, but remove it with the InstanceKlass since
530 // this place would be the only caller and it can share memory with transitive
531 // interfaces.
532 if (secondary_supers() != NULL &&
533 secondary_supers() != Universe::the_empty_klass_array() &&
534 // see comments in compute_secondary_supers about the following cast
535 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
536 !secondary_supers()->is_shared()) {
537 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
538 }
539 set_secondary_supers(NULL);
540
541 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
542 set_transitive_interfaces(NULL);
543 set_local_interfaces(NULL);
544
545 if (fields() != NULL && !fields()->is_shared()) {
546 MetadataFactory::free_array<jushort>(loader_data, fields());
547 }
548 set_fields(NULL, 0);
549
550 // If a method from a redefined class is using this constant pool, don't
551 // delete it, yet. The new class's previous version will point to this.
552 if (constants() != NULL) {
553 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
554 if (!constants()->is_shared()) {
555 MetadataFactory::free_metadata(loader_data, constants());
556 }
557 // Delete any cached resolution errors for the constant pool
558 SystemDictionary::delete_resolution_error(constants());
559
560 set_constants(NULL);
561 }
562
563 if (inner_classes() != NULL &&
564 inner_classes() != Universe::the_empty_short_array() &&
565 !inner_classes()->is_shared()) {
566 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
567 }
568 set_inner_classes(NULL);
569
570 if (nest_members() != NULL &&
571 nest_members() != Universe::the_empty_short_array() &&
572 !nest_members()->is_shared()) {
573 MetadataFactory::free_array<jushort>(loader_data, nest_members());
574 }
575 set_nest_members(NULL);
576
577 // We should deallocate the Annotations instance if it's not in shared spaces.
578 if (annotations() != NULL && !annotations()->is_shared()) {
579 MetadataFactory::free_metadata(loader_data, annotations());
580 }
581 set_annotations(NULL);
582 }
583
584 bool InstanceKlass::should_be_initialized() const {
585 return !is_initialized();
586 }
587
588 klassItable InstanceKlass::itable() const {
589 return klassItable(const_cast<InstanceKlass*>(this));
590 }
591
592 void InstanceKlass::eager_initialize(Thread *thread) {
593 if (!EagerInitialization) return;
594
595 if (this->is_not_initialized()) {
596 // abort if the the class has a class initializer
597 if (this->class_initializer() != NULL) return;
598
599 // abort if it is java.lang.Object (initialization is handled in genesis)
600 Klass* super_klass = super();
601 if (super_klass == NULL) return;
602
603 // abort if the super class should be initialized
604 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
605
606 // call body to expose the this pointer
607 eager_initialize_impl();
608 }
609 }
610
611 // JVMTI spec thinks there are signers and protection domain in the
612 // instanceKlass. These accessors pretend these fields are there.
613 // The hprof specification also thinks these fields are in InstanceKlass.
614 oop InstanceKlass::protection_domain() const {
615 // return the protection_domain from the mirror
616 return java_lang_Class::protection_domain(java_mirror());
617 }
618
619 // To remove these from requires an incompatible change and CCC request.
620 objArrayOop InstanceKlass::signers() const {
621 // return the signers from the mirror
622 return java_lang_Class::signers(java_mirror());
623 }
624
625 oop InstanceKlass::init_lock() const {
626 // return the init lock from the mirror
627 oop lock = java_lang_Class::init_lock(java_mirror());
628 // Prevent reordering with any access of initialization state
629 OrderAccess::loadload();
630 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
631 "only fully initialized state can have a null lock");
632 return lock;
633 }
634
635 // Set the initialization lock to null so the object can be GC'ed. Any racing
636 // threads to get this lock will see a null lock and will not lock.
637 // That's okay because they all check for initialized state after getting
638 // the lock and return.
639 void InstanceKlass::fence_and_clear_init_lock() {
640 // make sure previous stores are all done, notably the init_state.
641 OrderAccess::storestore();
642 java_lang_Class::set_init_lock(java_mirror(), NULL);
643 assert(!is_not_initialized(), "class must be initialized now");
644 }
645
646 void InstanceKlass::eager_initialize_impl() {
647 EXCEPTION_MARK;
648 HandleMark hm(THREAD);
649 Handle h_init_lock(THREAD, init_lock());
650 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
651
652 // abort if someone beat us to the initialization
653 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
654
655 ClassState old_state = init_state();
656 link_class_impl(THREAD);
657 if (HAS_PENDING_EXCEPTION) {
658 CLEAR_PENDING_EXCEPTION;
659 // Abort if linking the class throws an exception.
660
661 // Use a test to avoid redundantly resetting the state if there's
662 // no change. Set_init_state() asserts that state changes make
663 // progress, whereas here we might just be spinning in place.
664 if (old_state != _init_state)
665 set_init_state(old_state);
666 } else {
667 // linking successfull, mark class as initialized
668 set_init_state(fully_initialized);
669 fence_and_clear_init_lock();
670 // trace
671 if (log_is_enabled(Info, class, init)) {
672 ResourceMark rm(THREAD);
673 log_info(class, init)("[Initialized %s without side effects]", external_name());
674 }
675 }
676 }
677
678
679 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
680 // process. The step comments refers to the procedure described in that section.
681 // Note: implementation moved to static method to expose the this pointer.
682 void InstanceKlass::initialize(TRAPS) {
683 if (this->should_be_initialized()) {
684 initialize_impl(CHECK);
685 // Note: at this point the class may be initialized
686 // OR it may be in the state of being initialized
687 // in case of recursive initialization!
688 } else {
689 assert(is_initialized(), "sanity check");
690 }
691 }
692
693
694 bool InstanceKlass::verify_code(TRAPS) {
695 // 1) Verify the bytecodes
696 return Verifier::verify(this, should_verify_class(), THREAD);
697 }
698
699 void InstanceKlass::link_class(TRAPS) {
700 assert(is_loaded(), "must be loaded");
701 if (!is_linked()) {
702 link_class_impl(CHECK);
703 }
704 }
705
706 // Called to verify that a class can link during initialization, without
707 // throwing a VerifyError.
708 bool InstanceKlass::link_class_or_fail(TRAPS) {
709 assert(is_loaded(), "must be loaded");
710 if (!is_linked()) {
711 link_class_impl(CHECK_false);
712 }
713 return is_linked();
714 }
715
716 bool InstanceKlass::link_class_impl(TRAPS) {
717 if (DumpSharedSpaces && is_in_error_state()) {
718 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
719 // the class has failed verification. Throwing the NoClassDefFoundError here is just
720 // a convenient way to stop repeat attempts to verify the same (bad) class.
721 //
722 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
723 // if we are executing Java code. This is not a problem for CDS dumping phase since
724 // it doesn't execute any Java code.
725 ResourceMark rm(THREAD);
726 Exceptions::fthrow(THREAD_AND_LOCATION,
727 vmSymbols::java_lang_NoClassDefFoundError(),
728 "Class %s, or one of its supertypes, failed class initialization",
729 external_name());
730 return false;
731 }
732 // return if already verified
733 if (is_linked()) {
734 return true;
735 }
736
737 // Timing
738 // timer handles recursion
739 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
740 JavaThread* jt = (JavaThread*)THREAD;
741
742 // link super class before linking this class
743 Klass* super_klass = super();
744 if (super_klass != NULL) {
745 if (super_klass->is_interface()) { // check if super class is an interface
746 ResourceMark rm(THREAD);
747 Exceptions::fthrow(
748 THREAD_AND_LOCATION,
749 vmSymbols::java_lang_IncompatibleClassChangeError(),
750 "class %s has interface %s as super class",
751 external_name(),
752 super_klass->external_name()
753 );
754 return false;
755 }
756
757 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
758 ik_super->link_class_impl(CHECK_false);
759 }
760
761 // link all interfaces implemented by this class before linking this class
762 Array<InstanceKlass*>* interfaces = local_interfaces();
763 int num_interfaces = interfaces->length();
764 for (int index = 0; index < num_interfaces; index++) {
765 InstanceKlass* interk = interfaces->at(index);
766 interk->link_class_impl(CHECK_false);
767 }
768
769 // in case the class is linked in the process of linking its superclasses
770 if (is_linked()) {
771 return true;
772 }
773
774 // trace only the link time for this klass that includes
775 // the verification time
776 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
777 ClassLoader::perf_class_link_selftime(),
778 ClassLoader::perf_classes_linked(),
779 jt->get_thread_stat()->perf_recursion_counts_addr(),
780 jt->get_thread_stat()->perf_timers_addr(),
781 PerfClassTraceTime::CLASS_LINK);
782
783 // verification & rewriting
784 {
785 HandleMark hm(THREAD);
786 Handle h_init_lock(THREAD, init_lock());
787 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
788 // rewritten will have been set if loader constraint error found
789 // on an earlier link attempt
790 // don't verify or rewrite if already rewritten
791 //
792
793 if (!is_linked()) {
794 if (!is_rewritten()) {
795 {
796 bool verify_ok = verify_code(THREAD);
797 if (!verify_ok) {
798 return false;
799 }
800 }
801
802 // Just in case a side-effect of verify linked this class already
803 // (which can sometimes happen since the verifier loads classes
804 // using custom class loaders, which are free to initialize things)
805 if (is_linked()) {
806 return true;
807 }
808
809 // also sets rewritten
810 rewrite_class(CHECK_false);
811 } else if (is_shared()) {
812 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
813 }
814
815 // relocate jsrs and link methods after they are all rewritten
816 link_methods(CHECK_false);
817
818 // Initialize the vtable and interface table after
819 // methods have been rewritten since rewrite may
820 // fabricate new Method*s.
821 // also does loader constraint checking
822 //
823 // initialize_vtable and initialize_itable need to be rerun for
824 // a shared class if the class is not loaded by the NULL classloader.
825 ClassLoaderData * loader_data = class_loader_data();
826 if (!(is_shared() &&
827 loader_data->is_the_null_class_loader_data())) {
828 vtable().initialize_vtable(true, CHECK_false);
829 itable().initialize_itable(true, CHECK_false);
830 }
831 #ifdef ASSERT
832 else {
833 vtable().verify(tty, true);
834 // In case itable verification is ever added.
835 // itable().verify(tty, true);
836 }
837 #endif
838 set_init_state(linked);
839 if (JvmtiExport::should_post_class_prepare()) {
840 Thread *thread = THREAD;
841 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
842 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
843 }
844 }
845 }
846 return true;
847 }
848
849 // Rewrite the byte codes of all of the methods of a class.
850 // The rewriter must be called exactly once. Rewriting must happen after
851 // verification but before the first method of the class is executed.
852 void InstanceKlass::rewrite_class(TRAPS) {
853 assert(is_loaded(), "must be loaded");
854 if (is_rewritten()) {
855 assert(is_shared(), "rewriting an unshared class?");
856 return;
857 }
858 Rewriter::rewrite(this, CHECK);
859 set_rewritten();
860 }
861
862 // Now relocate and link method entry points after class is rewritten.
863 // This is outside is_rewritten flag. In case of an exception, it can be
864 // executed more than once.
865 void InstanceKlass::link_methods(TRAPS) {
866 int len = methods()->length();
867 for (int i = len-1; i >= 0; i--) {
868 methodHandle m(THREAD, methods()->at(i));
869
870 // Set up method entry points for compiler and interpreter .
871 m->link_method(m, CHECK);
872 }
873 }
874
875 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
876 void InstanceKlass::initialize_super_interfaces(TRAPS) {
877 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
878 for (int i = 0; i < local_interfaces()->length(); ++i) {
879 InstanceKlass* ik = local_interfaces()->at(i);
880
881 // Initialization is depth first search ie. we start with top of the inheritance tree
882 // has_nonstatic_concrete_methods drives searching superinterfaces since it
883 // means has_nonstatic_concrete_methods in its superinterface hierarchy
884 if (ik->has_nonstatic_concrete_methods()) {
885 ik->initialize_super_interfaces(CHECK);
886 }
887
888 // Only initialize() interfaces that "declare" concrete methods.
889 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
890 ik->initialize(CHECK);
891 }
892 }
893 }
894
895 void InstanceKlass::initialize_impl(TRAPS) {
896 HandleMark hm(THREAD);
897
898 // Make sure klass is linked (verified) before initialization
899 // A class could already be verified, since it has been reflected upon.
900 link_class(CHECK);
901
902 DTRACE_CLASSINIT_PROBE(required, -1);
903
904 bool wait = false;
905
906 // refer to the JVM book page 47 for description of steps
907 // Step 1
908 {
909 Handle h_init_lock(THREAD, init_lock());
910 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
911
912 Thread *self = THREAD; // it's passed the current thread
913
914 // Step 2
915 // If we were to use wait() instead of waitInterruptibly() then
916 // we might end up throwing IE from link/symbol resolution sites
917 // that aren't expected to throw. This would wreak havoc. See 6320309.
918 while(is_being_initialized() && !is_reentrant_initialization(self)) {
919 wait = true;
920 ol.waitUninterruptibly(CHECK);
921 }
922
923 // Step 3
924 if (is_being_initialized() && is_reentrant_initialization(self)) {
925 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
926 return;
927 }
928
929 // Step 4
930 if (is_initialized()) {
931 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
932 return;
933 }
934
935 // Step 5
936 if (is_in_error_state()) {
937 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
938 ResourceMark rm(THREAD);
939 const char* desc = "Could not initialize class ";
940 const char* className = external_name();
941 size_t msglen = strlen(desc) + strlen(className) + 1;
942 char* message = NEW_RESOURCE_ARRAY(char, msglen);
943 if (NULL == message) {
944 // Out of memory: can't create detailed error message
945 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
946 } else {
947 jio_snprintf(message, msglen, "%s%s", desc, className);
948 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
949 }
950 }
951
952 // Step 6
953 set_init_state(being_initialized);
954 set_init_thread(self);
955 }
956
957 // Step 7
958 // Next, if C is a class rather than an interface, initialize it's super class and super
959 // interfaces.
960 if (!is_interface()) {
961 Klass* super_klass = super();
962 if (super_klass != NULL && super_klass->should_be_initialized()) {
963 super_klass->initialize(THREAD);
964 }
965 // If C implements any interface that declares a non-static, concrete method,
966 // the initialization of C triggers initialization of its super interfaces.
967 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
968 // having a superinterface that declares, non-static, concrete methods
969 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
970 initialize_super_interfaces(THREAD);
971 }
972
973 // If any exceptions, complete abruptly, throwing the same exception as above.
974 if (HAS_PENDING_EXCEPTION) {
975 Handle e(THREAD, PENDING_EXCEPTION);
976 CLEAR_PENDING_EXCEPTION;
977 {
978 EXCEPTION_MARK;
979 // Locks object, set state, and notify all waiting threads
980 set_initialization_state_and_notify(initialization_error, THREAD);
981 CLEAR_PENDING_EXCEPTION;
982 }
983 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
984 THROW_OOP(e());
985 }
986 }
987
988
989 // Look for aot compiled methods for this klass, including class initializer.
990 AOTLoader::load_for_klass(this, THREAD);
991
992 // Step 8
993 {
994 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
995 JavaThread* jt = (JavaThread*)THREAD;
996 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
997 // Timer includes any side effects of class initialization (resolution,
998 // etc), but not recursive entry into call_class_initializer().
999 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1000 ClassLoader::perf_class_init_selftime(),
1001 ClassLoader::perf_classes_inited(),
1002 jt->get_thread_stat()->perf_recursion_counts_addr(),
1003 jt->get_thread_stat()->perf_timers_addr(),
1004 PerfClassTraceTime::CLASS_CLINIT);
1005 call_class_initializer(THREAD);
1006 }
1007
1008 // Step 9
1009 if (!HAS_PENDING_EXCEPTION) {
1010 set_initialization_state_and_notify(fully_initialized, CHECK);
1011 {
1012 debug_only(vtable().verify(tty, true);)
1013 }
1014 }
1015 else {
1016 // Step 10 and 11
1017 Handle e(THREAD, PENDING_EXCEPTION);
1018 CLEAR_PENDING_EXCEPTION;
1019 // JVMTI has already reported the pending exception
1020 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1021 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1022 {
1023 EXCEPTION_MARK;
1024 set_initialization_state_and_notify(initialization_error, THREAD);
1025 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1026 // JVMTI has already reported the pending exception
1027 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1028 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1029 }
1030 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1031 if (e->is_a(SystemDictionary::Error_klass())) {
1032 THROW_OOP(e());
1033 } else {
1034 JavaCallArguments args(e);
1035 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1036 vmSymbols::throwable_void_signature(),
1037 &args);
1038 }
1039 }
1040 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1041 }
1042
1043
1044 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1045 Handle h_init_lock(THREAD, init_lock());
1046 if (h_init_lock() != NULL) {
1047 ObjectLocker ol(h_init_lock, THREAD);
1048 set_init_state(state);
1049 fence_and_clear_init_lock();
1050 ol.notify_all(CHECK);
1051 } else {
1052 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1053 set_init_state(state);
1054 }
1055 }
1056
1057 Klass* InstanceKlass::implementor() const {
1058 Klass* volatile* k = adr_implementor();
1059 if (k == NULL) {
1060 return NULL;
1061 } else {
1062 // This load races with inserts, and therefore needs acquire.
1063 Klass* kls = OrderAccess::load_acquire(k);
1064 if (kls != NULL && !kls->is_loader_alive()) {
1065 return NULL; // don't return unloaded class
1066 } else {
1067 return kls;
1068 }
1069 }
1070 }
1071
1072
1073 void InstanceKlass::set_implementor(Klass* k) {
1074 assert_lock_strong(Compile_lock);
1075 assert(is_interface(), "not interface");
1076 Klass* volatile* addr = adr_implementor();
1077 assert(addr != NULL, "null addr");
1078 if (addr != NULL) {
1079 OrderAccess::release_store(addr, k);
1080 }
1081 }
1082
1083 int InstanceKlass::nof_implementors() const {
1084 Klass* k = implementor();
1085 if (k == NULL) {
1086 return 0;
1087 } else if (k != this) {
1088 return 1;
1089 } else {
1090 return 2;
1091 }
1092 }
1093
1094 // The embedded _implementor field can only record one implementor.
1095 // When there are more than one implementors, the _implementor field
1096 // is set to the interface Klass* itself. Following are the possible
1097 // values for the _implementor field:
1098 // NULL - no implementor
1099 // implementor Klass* - one implementor
1100 // self - more than one implementor
1101 //
1102 // The _implementor field only exists for interfaces.
1103 void InstanceKlass::add_implementor(Klass* k) {
1104 assert_lock_strong(Compile_lock);
1105 assert(is_interface(), "not interface");
1106 // Filter out my subinterfaces.
1107 // (Note: Interfaces are never on the subklass list.)
1108 if (InstanceKlass::cast(k)->is_interface()) return;
1109
1110 // Filter out subclasses whose supers already implement me.
1111 // (Note: CHA must walk subclasses of direct implementors
1112 // in order to locate indirect implementors.)
1113 Klass* sk = k->super();
1114 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1115 // We only need to check one immediate superclass, since the
1116 // implements_interface query looks at transitive_interfaces.
1117 // Any supers of the super have the same (or fewer) transitive_interfaces.
1118 return;
1119
1120 Klass* ik = implementor();
1121 if (ik == NULL) {
1122 set_implementor(k);
1123 } else if (ik != this) {
1124 // There is already an implementor. Use itself as an indicator of
1125 // more than one implementors.
1126 set_implementor(this);
1127 }
1128
1129 // The implementor also implements the transitive_interfaces
1130 for (int index = 0; index < local_interfaces()->length(); index++) {
1131 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1132 }
1133 }
1134
1135 void InstanceKlass::init_implementor() {
1136 if (is_interface()) {
1137 set_implementor(NULL);
1138 }
1139 }
1140
1141
1142 void InstanceKlass::process_interfaces(Thread *thread) {
1143 // link this class into the implementors list of every interface it implements
1144 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1145 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1146 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1147 assert(interf->is_interface(), "expected interface");
1148 interf->add_implementor(this);
1149 }
1150 }
1151
1152 bool InstanceKlass::can_be_primary_super_slow() const {
1153 if (is_interface())
1154 return false;
1155 else
1156 return Klass::can_be_primary_super_slow();
1157 }
1158
1159 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1160 Array<InstanceKlass*>* transitive_interfaces) {
1161 // The secondaries are the implemented interfaces.
1162 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1163 int num_secondaries = num_extra_slots + interfaces->length();
1164 if (num_secondaries == 0) {
1165 // Must share this for correct bootstrapping!
1166 set_secondary_supers(Universe::the_empty_klass_array());
1167 return NULL;
1168 } else if (num_extra_slots == 0) {
1169 // The secondary super list is exactly the same as the transitive interfaces, so
1170 // let's use it instead of making a copy.
1171 // Redefine classes has to be careful not to delete this!
1172 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1173 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1174 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1175 return NULL;
1176 } else {
1177 // Copy transitive interfaces to a temporary growable array to be constructed
1178 // into the secondary super list with extra slots.
1179 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1180 for (int i = 0; i < interfaces->length(); i++) {
1181 secondaries->push(interfaces->at(i));
1182 }
1183 return secondaries;
1184 }
1185 }
1186
1187 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1188 if (k->is_interface()) {
1189 return implements_interface(k);
1190 } else {
1191 return Klass::compute_is_subtype_of(k);
1192 }
1193 }
1194
1195 bool InstanceKlass::implements_interface(Klass* k) const {
1196 if (this == k) return true;
1197 assert(k->is_interface(), "should be an interface class");
1198 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1199 if (transitive_interfaces()->at(i) == k) {
1200 return true;
1201 }
1202 }
1203 return false;
1204 }
1205
1206 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1207 // Verify direct super interface
1208 if (this == k) return true;
1209 assert(k->is_interface(), "should be an interface class");
1210 for (int i = 0; i < local_interfaces()->length(); i++) {
1211 if (local_interfaces()->at(i) == k) {
1212 return true;
1213 }
1214 }
1215 return false;
1216 }
1217
1218 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1219 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1220 int size = objArrayOopDesc::object_size(length);
1221 Klass* ak = array_klass(n, CHECK_NULL);
1222 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1223 /* do_zero */ true, CHECK_NULL);
1224 return o;
1225 }
1226
1227 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1228 if (TraceFinalizerRegistration) {
1229 tty->print("Registered ");
1230 i->print_value_on(tty);
1231 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1232 }
1233 instanceHandle h_i(THREAD, i);
1234 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1235 JavaValue result(T_VOID);
1236 JavaCallArguments args(h_i);
1237 methodHandle mh (THREAD, Universe::finalizer_register_method());
1238 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1239 return h_i();
1240 }
1241
1242 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1243 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1244 int size = size_helper(); // Query before forming handle.
1245
1246 instanceOop i;
1247
1248 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1249 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1250 i = register_finalizer(i, CHECK_NULL);
1251 }
1252 return i;
1253 }
1254
1255 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1256 return instanceHandle(THREAD, allocate_instance(THREAD));
1257 }
1258
1259 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1260 if (is_interface() || is_abstract()) {
1261 ResourceMark rm(THREAD);
1262 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1263 : vmSymbols::java_lang_InstantiationException(), external_name());
1264 }
1265 if (this == SystemDictionary::Class_klass()) {
1266 ResourceMark rm(THREAD);
1267 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1268 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1269 }
1270 }
1271
1272 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1273 // Need load-acquire for lock-free read
1274 if (array_klasses_acquire() == NULL) {
1275 if (or_null) return NULL;
1276
1277 ResourceMark rm;
1278 JavaThread *jt = (JavaThread *)THREAD;
1279 {
1280 // Atomic creation of array_klasses
1281 MutexLocker mc(Compile_lock, THREAD); // for vtables
1282 MutexLocker ma(MultiArray_lock, THREAD);
1283
1284 // Check if update has already taken place
1285 if (array_klasses() == NULL) {
1286 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1287 // use 'release' to pair with lock-free load
1288 release_set_array_klasses(k);
1289 }
1290 }
1291 }
1292 // _this will always be set at this point
1293 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1294 if (or_null) {
1295 return oak->array_klass_or_null(n);
1296 }
1297 return oak->array_klass(n, THREAD);
1298 }
1299
1300 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1301 return array_klass_impl(or_null, 1, THREAD);
1302 }
1303
1304 static int call_class_initializer_counter = 0; // for debugging
1305
1306 Method* InstanceKlass::class_initializer() const {
1307 Method* clinit = find_method(
1308 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1309 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1310 return clinit;
1311 }
1312 return NULL;
1313 }
1314
1315 void InstanceKlass::call_class_initializer(TRAPS) {
1316 if (ReplayCompiles &&
1317 (ReplaySuppressInitializers == 1 ||
1318 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1319 // Hide the existence of the initializer for the purpose of replaying the compile
1320 return;
1321 }
1322
1323 methodHandle h_method(THREAD, class_initializer());
1324 assert(!is_initialized(), "we cannot initialize twice");
1325 LogTarget(Info, class, init) lt;
1326 if (lt.is_enabled()) {
1327 ResourceMark rm;
1328 LogStream ls(lt);
1329 ls.print("%d Initializing ", call_class_initializer_counter++);
1330 name()->print_value_on(&ls);
1331 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1332 }
1333 if (h_method() != NULL) {
1334 JavaCallArguments args; // No arguments
1335 JavaValue result(T_VOID);
1336 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1337 }
1338 }
1339
1340
1341 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1342 InterpreterOopMap* entry_for) {
1343 // Lazily create the _oop_map_cache at first request
1344 // Lock-free access requires load_acquire.
1345 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1346 if (oop_map_cache == NULL) {
1347 MutexLocker x(OopMapCacheAlloc_lock);
1348 // Check if _oop_map_cache was allocated while we were waiting for this lock
1349 if ((oop_map_cache = _oop_map_cache) == NULL) {
1350 oop_map_cache = new OopMapCache();
1351 // Ensure _oop_map_cache is stable, since it is examined without a lock
1352 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1353 }
1354 }
1355 // _oop_map_cache is constant after init; lookup below does its own locking.
1356 oop_map_cache->lookup(method, bci, entry_for);
1357 }
1358
1359
1360 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1361 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1362 Symbol* f_name = fs.name();
1363 Symbol* f_sig = fs.signature();
1364 if (f_name == name && f_sig == sig) {
1365 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1366 return true;
1367 }
1368 }
1369 return false;
1370 }
1371
1372
1373 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1374 const int n = local_interfaces()->length();
1375 for (int i = 0; i < n; i++) {
1376 Klass* intf1 = local_interfaces()->at(i);
1377 assert(intf1->is_interface(), "just checking type");
1378 // search for field in current interface
1379 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1380 assert(fd->is_static(), "interface field must be static");
1381 return intf1;
1382 }
1383 // search for field in direct superinterfaces
1384 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1385 if (intf2 != NULL) return intf2;
1386 }
1387 // otherwise field lookup fails
1388 return NULL;
1389 }
1390
1391
1392 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1393 // search order according to newest JVM spec (5.4.3.2, p.167).
1394 // 1) search for field in current klass
1395 if (find_local_field(name, sig, fd)) {
1396 return const_cast<InstanceKlass*>(this);
1397 }
1398 // 2) search for field recursively in direct superinterfaces
1399 { Klass* intf = find_interface_field(name, sig, fd);
1400 if (intf != NULL) return intf;
1401 }
1402 // 3) apply field lookup recursively if superclass exists
1403 { Klass* supr = super();
1404 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1405 }
1406 // 4) otherwise field lookup fails
1407 return NULL;
1408 }
1409
1410
1411 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1412 // search order according to newest JVM spec (5.4.3.2, p.167).
1413 // 1) search for field in current klass
1414 if (find_local_field(name, sig, fd)) {
1415 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1416 }
1417 // 2) search for field recursively in direct superinterfaces
1418 if (is_static) {
1419 Klass* intf = find_interface_field(name, sig, fd);
1420 if (intf != NULL) return intf;
1421 }
1422 // 3) apply field lookup recursively if superclass exists
1423 { Klass* supr = super();
1424 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1425 }
1426 // 4) otherwise field lookup fails
1427 return NULL;
1428 }
1429
1430
1431 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1432 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1433 if (fs.offset() == offset) {
1434 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1435 if (fd->is_static() == is_static) return true;
1436 }
1437 }
1438 return false;
1439 }
1440
1441
1442 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1443 Klass* klass = const_cast<InstanceKlass*>(this);
1444 while (klass != NULL) {
1445 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1446 return true;
1447 }
1448 klass = klass->super();
1449 }
1450 return false;
1451 }
1452
1453
1454 void InstanceKlass::methods_do(void f(Method* method)) {
1455 // Methods aren't stable until they are loaded. This can be read outside
1456 // a lock through the ClassLoaderData for profiling
1457 if (!is_loaded()) {
1458 return;
1459 }
1460
1461 int len = methods()->length();
1462 for (int index = 0; index < len; index++) {
1463 Method* m = methods()->at(index);
1464 assert(m->is_method(), "must be method");
1465 f(m);
1466 }
1467 }
1468
1469
1470 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1471 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1472 if (fs.access_flags().is_static()) {
1473 fieldDescriptor& fd = fs.field_descriptor();
1474 cl->do_field(&fd);
1475 }
1476 }
1477 }
1478
1479
1480 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1481 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1482 if (fs.access_flags().is_static()) {
1483 fieldDescriptor& fd = fs.field_descriptor();
1484 f(&fd, mirror, CHECK);
1485 }
1486 }
1487 }
1488
1489
1490 static int compare_fields_by_offset(int* a, int* b) {
1491 return a[0] - b[0];
1492 }
1493
1494 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1495 InstanceKlass* super = superklass();
1496 if (super != NULL) {
1497 super->do_nonstatic_fields(cl);
1498 }
1499 fieldDescriptor fd;
1500 int length = java_fields_count();
1501 // In DebugInfo nonstatic fields are sorted by offset.
1502 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1503 int j = 0;
1504 for (int i = 0; i < length; i += 1) {
1505 fd.reinitialize(this, i);
1506 if (!fd.is_static()) {
1507 fields_sorted[j + 0] = fd.offset();
1508 fields_sorted[j + 1] = i;
1509 j += 2;
1510 }
1511 }
1512 if (j > 0) {
1513 length = j;
1514 // _sort_Fn is defined in growableArray.hpp.
1515 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1516 for (int i = 0; i < length; i += 2) {
1517 fd.reinitialize(this, fields_sorted[i + 1]);
1518 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1519 cl->do_field(&fd);
1520 }
1521 }
1522 FREE_C_HEAP_ARRAY(int, fields_sorted);
1523 }
1524
1525
1526 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1527 if (array_klasses() != NULL)
1528 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1529 }
1530
1531 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1532 if (array_klasses() != NULL)
1533 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1534 }
1535
1536 #ifdef ASSERT
1537 static int linear_search(const Array<Method*>* methods,
1538 const Symbol* name,
1539 const Symbol* signature) {
1540 const int len = methods->length();
1541 for (int index = 0; index < len; index++) {
1542 const Method* const m = methods->at(index);
1543 assert(m->is_method(), "must be method");
1544 if (m->signature() == signature && m->name() == name) {
1545 return index;
1546 }
1547 }
1548 return -1;
1549 }
1550 #endif
1551
1552 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1553 int len = methods->length();
1554 // methods are sorted, so do binary search
1555 int l = 0;
1556 int h = len - 1;
1557 while (l <= h) {
1558 int mid = (l + h) >> 1;
1559 Method* m = methods->at(mid);
1560 assert(m->is_method(), "must be method");
1561 int res = m->name()->fast_compare(name);
1562 if (res == 0) {
1563 return mid;
1564 } else if (res < 0) {
1565 l = mid + 1;
1566 } else {
1567 h = mid - 1;
1568 }
1569 }
1570 return -1;
1571 }
1572
1573 // find_method looks up the name/signature in the local methods array
1574 Method* InstanceKlass::find_method(const Symbol* name,
1575 const Symbol* signature) const {
1576 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1577 }
1578
1579 Method* InstanceKlass::find_method_impl(const Symbol* name,
1580 const Symbol* signature,
1581 OverpassLookupMode overpass_mode,
1582 StaticLookupMode static_mode,
1583 PrivateLookupMode private_mode) const {
1584 return InstanceKlass::find_method_impl(methods(),
1585 name,
1586 signature,
1587 overpass_mode,
1588 static_mode,
1589 private_mode);
1590 }
1591
1592 // find_instance_method looks up the name/signature in the local methods array
1593 // and skips over static methods
1594 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1595 const Symbol* name,
1596 const Symbol* signature,
1597 PrivateLookupMode private_mode) {
1598 Method* const meth = InstanceKlass::find_method_impl(methods,
1599 name,
1600 signature,
1601 find_overpass,
1602 skip_static,
1603 private_mode);
1604 assert(((meth == NULL) || !meth->is_static()),
1605 "find_instance_method should have skipped statics");
1606 return meth;
1607 }
1608
1609 // find_instance_method looks up the name/signature in the local methods array
1610 // and skips over static methods
1611 Method* InstanceKlass::find_instance_method(const Symbol* name,
1612 const Symbol* signature,
1613 PrivateLookupMode private_mode) const {
1614 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1615 }
1616
1617 // Find looks up the name/signature in the local methods array
1618 // and filters on the overpass, static and private flags
1619 // This returns the first one found
1620 // note that the local methods array can have up to one overpass, one static
1621 // and one instance (private or not) with the same name/signature
1622 Method* InstanceKlass::find_local_method(const Symbol* name,
1623 const Symbol* signature,
1624 OverpassLookupMode overpass_mode,
1625 StaticLookupMode static_mode,
1626 PrivateLookupMode private_mode) const {
1627 return InstanceKlass::find_method_impl(methods(),
1628 name,
1629 signature,
1630 overpass_mode,
1631 static_mode,
1632 private_mode);
1633 }
1634
1635 // Find looks up the name/signature in the local methods array
1636 // and filters on the overpass, static and private flags
1637 // This returns the first one found
1638 // note that the local methods array can have up to one overpass, one static
1639 // and one instance (private or not) with the same name/signature
1640 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1641 const Symbol* name,
1642 const Symbol* signature,
1643 OverpassLookupMode overpass_mode,
1644 StaticLookupMode static_mode,
1645 PrivateLookupMode private_mode) {
1646 return InstanceKlass::find_method_impl(methods,
1647 name,
1648 signature,
1649 overpass_mode,
1650 static_mode,
1651 private_mode);
1652 }
1653
1654 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1655 const Symbol* name,
1656 const Symbol* signature) {
1657 return InstanceKlass::find_method_impl(methods,
1658 name,
1659 signature,
1660 find_overpass,
1661 find_static,
1662 find_private);
1663 }
1664
1665 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1666 const Symbol* name,
1667 const Symbol* signature,
1668 OverpassLookupMode overpass_mode,
1669 StaticLookupMode static_mode,
1670 PrivateLookupMode private_mode) {
1671 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1672 return hit >= 0 ? methods->at(hit): NULL;
1673 }
1674
1675 // true if method matches signature and conforms to skipping_X conditions.
1676 static bool method_matches(const Method* m,
1677 const Symbol* signature,
1678 bool skipping_overpass,
1679 bool skipping_static,
1680 bool skipping_private) {
1681 return ((m->signature() == signature) &&
1682 (!skipping_overpass || !m->is_overpass()) &&
1683 (!skipping_static || !m->is_static()) &&
1684 (!skipping_private || !m->is_private()));
1685 }
1686
1687 // Used directly for default_methods to find the index into the
1688 // default_vtable_indices, and indirectly by find_method
1689 // find_method_index looks in the local methods array to return the index
1690 // of the matching name/signature. If, overpass methods are being ignored,
1691 // the search continues to find a potential non-overpass match. This capability
1692 // is important during method resolution to prefer a static method, for example,
1693 // over an overpass method.
1694 // There is the possibility in any _method's array to have the same name/signature
1695 // for a static method, an overpass method and a local instance method
1696 // To correctly catch a given method, the search criteria may need
1697 // to explicitly skip the other two. For local instance methods, it
1698 // is often necessary to skip private methods
1699 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1700 const Symbol* name,
1701 const Symbol* signature,
1702 OverpassLookupMode overpass_mode,
1703 StaticLookupMode static_mode,
1704 PrivateLookupMode private_mode) {
1705 const bool skipping_overpass = (overpass_mode == skip_overpass);
1706 const bool skipping_static = (static_mode == skip_static);
1707 const bool skipping_private = (private_mode == skip_private);
1708 const int hit = binary_search(methods, name);
1709 if (hit != -1) {
1710 const Method* const m = methods->at(hit);
1711
1712 // Do linear search to find matching signature. First, quick check
1713 // for common case, ignoring overpasses if requested.
1714 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1715 return hit;
1716 }
1717
1718 // search downwards through overloaded methods
1719 int i;
1720 for (i = hit - 1; i >= 0; --i) {
1721 const Method* const m = methods->at(i);
1722 assert(m->is_method(), "must be method");
1723 if (m->name() != name) {
1724 break;
1725 }
1726 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1727 return i;
1728 }
1729 }
1730 // search upwards
1731 for (i = hit + 1; i < methods->length(); ++i) {
1732 const Method* const m = methods->at(i);
1733 assert(m->is_method(), "must be method");
1734 if (m->name() != name) {
1735 break;
1736 }
1737 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1738 return i;
1739 }
1740 }
1741 // not found
1742 #ifdef ASSERT
1743 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1744 linear_search(methods, name, signature);
1745 assert(-1 == index, "binary search should have found entry %d", index);
1746 #endif
1747 }
1748 return -1;
1749 }
1750
1751 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1752 return find_method_by_name(methods(), name, end);
1753 }
1754
1755 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1756 const Symbol* name,
1757 int* end_ptr) {
1758 assert(end_ptr != NULL, "just checking");
1759 int start = binary_search(methods, name);
1760 int end = start + 1;
1761 if (start != -1) {
1762 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1763 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1764 *end_ptr = end;
1765 return start;
1766 }
1767 return -1;
1768 }
1769
1770 // uncached_lookup_method searches both the local class methods array and all
1771 // superclasses methods arrays, skipping any overpass methods in superclasses,
1772 // and possibly skipping private methods.
1773 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1774 const Symbol* signature,
1775 OverpassLookupMode overpass_mode,
1776 PrivateLookupMode private_mode) const {
1777 OverpassLookupMode overpass_local_mode = overpass_mode;
1778 const Klass* klass = this;
1779 while (klass != NULL) {
1780 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1781 signature,
1782 overpass_local_mode,
1783 find_static,
1784 private_mode);
1785 if (method != NULL) {
1786 return method;
1787 }
1788 klass = klass->super();
1789 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1790 }
1791 return NULL;
1792 }
1793
1794 #ifdef ASSERT
1795 // search through class hierarchy and return true if this class or
1796 // one of the superclasses was redefined
1797 bool InstanceKlass::has_redefined_this_or_super() const {
1798 const Klass* klass = this;
1799 while (klass != NULL) {
1800 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1801 return true;
1802 }
1803 klass = klass->super();
1804 }
1805 return false;
1806 }
1807 #endif
1808
1809 // lookup a method in the default methods list then in all transitive interfaces
1810 // Do NOT return private or static methods
1811 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1812 Symbol* signature) const {
1813 Method* m = NULL;
1814 if (default_methods() != NULL) {
1815 m = find_method(default_methods(), name, signature);
1816 }
1817 // Look up interfaces
1818 if (m == NULL) {
1819 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1820 }
1821 return m;
1822 }
1823
1824 // lookup a method in all the interfaces that this class implements
1825 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1826 // They should only be found in the initial InterfaceMethodRef
1827 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1828 Symbol* signature,
1829 DefaultsLookupMode defaults_mode) const {
1830 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1831 int num_ifs = all_ifs->length();
1832 InstanceKlass *ik = NULL;
1833 for (int i = 0; i < num_ifs; i++) {
1834 ik = all_ifs->at(i);
1835 Method* m = ik->lookup_method(name, signature);
1836 if (m != NULL && m->is_public() && !m->is_static() &&
1837 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1838 return m;
1839 }
1840 }
1841 return NULL;
1842 }
1843
1844 /* jni_id_for_impl for jfieldIds only */
1845 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1846 MutexLocker ml(JfieldIdCreation_lock);
1847 // Retry lookup after we got the lock
1848 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1849 if (probe == NULL) {
1850 // Slow case, allocate new static field identifier
1851 probe = new JNIid(this, offset, jni_ids());
1852 set_jni_ids(probe);
1853 }
1854 return probe;
1855 }
1856
1857
1858 /* jni_id_for for jfieldIds only */
1859 JNIid* InstanceKlass::jni_id_for(int offset) {
1860 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1861 if (probe == NULL) {
1862 probe = jni_id_for_impl(offset);
1863 }
1864 return probe;
1865 }
1866
1867 u2 InstanceKlass::enclosing_method_data(int offset) const {
1868 const Array<jushort>* const inner_class_list = inner_classes();
1869 if (inner_class_list == NULL) {
1870 return 0;
1871 }
1872 const int length = inner_class_list->length();
1873 if (length % inner_class_next_offset == 0) {
1874 return 0;
1875 }
1876 const int index = length - enclosing_method_attribute_size;
1877 assert(offset < enclosing_method_attribute_size, "invalid offset");
1878 return inner_class_list->at(index + offset);
1879 }
1880
1881 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1882 u2 method_index) {
1883 Array<jushort>* inner_class_list = inner_classes();
1884 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1885 int length = inner_class_list->length();
1886 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1887 int index = length - enclosing_method_attribute_size;
1888 inner_class_list->at_put(
1889 index + enclosing_method_class_index_offset, class_index);
1890 inner_class_list->at_put(
1891 index + enclosing_method_method_index_offset, method_index);
1892 }
1893 }
1894
1895 // Lookup or create a jmethodID.
1896 // This code is called by the VMThread and JavaThreads so the
1897 // locking has to be done very carefully to avoid deadlocks
1898 // and/or other cache consistency problems.
1899 //
1900 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1901 size_t idnum = (size_t)method_h->method_idnum();
1902 jmethodID* jmeths = methods_jmethod_ids_acquire();
1903 size_t length = 0;
1904 jmethodID id = NULL;
1905
1906 // We use a double-check locking idiom here because this cache is
1907 // performance sensitive. In the normal system, this cache only
1908 // transitions from NULL to non-NULL which is safe because we use
1909 // release_set_methods_jmethod_ids() to advertise the new cache.
1910 // A partially constructed cache should never be seen by a racing
1911 // thread. We also use release_store() to save a new jmethodID
1912 // in the cache so a partially constructed jmethodID should never be
1913 // seen either. Cache reads of existing jmethodIDs proceed without a
1914 // lock, but cache writes of a new jmethodID requires uniqueness and
1915 // creation of the cache itself requires no leaks so a lock is
1916 // generally acquired in those two cases.
1917 //
1918 // If the RedefineClasses() API has been used, then this cache can
1919 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1920 // Cache creation requires no leaks and we require safety between all
1921 // cache accesses and freeing of the old cache so a lock is generally
1922 // acquired when the RedefineClasses() API has been used.
1923
1924 if (jmeths != NULL) {
1925 // the cache already exists
1926 if (!idnum_can_increment()) {
1927 // the cache can't grow so we can just get the current values
1928 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1929 } else {
1930 // cache can grow so we have to be more careful
1931 if (Threads::number_of_threads() == 0 ||
1932 SafepointSynchronize::is_at_safepoint()) {
1933 // we're single threaded or at a safepoint - no locking needed
1934 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1935 } else {
1936 MutexLocker ml(JmethodIdCreation_lock);
1937 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1938 }
1939 }
1940 }
1941 // implied else:
1942 // we need to allocate a cache so default length and id values are good
1943
1944 if (jmeths == NULL || // no cache yet
1945 length <= idnum || // cache is too short
1946 id == NULL) { // cache doesn't contain entry
1947
1948 // This function can be called by the VMThread so we have to do all
1949 // things that might block on a safepoint before grabbing the lock.
1950 // Otherwise, we can deadlock with the VMThread or have a cache
1951 // consistency issue. These vars keep track of what we might have
1952 // to free after the lock is dropped.
1953 jmethodID to_dealloc_id = NULL;
1954 jmethodID* to_dealloc_jmeths = NULL;
1955
1956 // may not allocate new_jmeths or use it if we allocate it
1957 jmethodID* new_jmeths = NULL;
1958 if (length <= idnum) {
1959 // allocate a new cache that might be used
1960 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1961 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1962 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1963 // cache size is stored in element[0], other elements offset by one
1964 new_jmeths[0] = (jmethodID)size;
1965 }
1966
1967 // allocate a new jmethodID that might be used
1968 jmethodID new_id = NULL;
1969 if (method_h->is_old() && !method_h->is_obsolete()) {
1970 // The method passed in is old (but not obsolete), we need to use the current version
1971 Method* current_method = method_with_idnum((int)idnum);
1972 assert(current_method != NULL, "old and but not obsolete, so should exist");
1973 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1974 } else {
1975 // It is the current version of the method or an obsolete method,
1976 // use the version passed in
1977 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1978 }
1979
1980 if (Threads::number_of_threads() == 0 ||
1981 SafepointSynchronize::is_at_safepoint()) {
1982 // we're single threaded or at a safepoint - no locking needed
1983 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1984 &to_dealloc_id, &to_dealloc_jmeths);
1985 } else {
1986 MutexLocker ml(JmethodIdCreation_lock);
1987 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1988 &to_dealloc_id, &to_dealloc_jmeths);
1989 }
1990
1991 // The lock has been dropped so we can free resources.
1992 // Free up either the old cache or the new cache if we allocated one.
1993 if (to_dealloc_jmeths != NULL) {
1994 FreeHeap(to_dealloc_jmeths);
1995 }
1996 // free up the new ID since it wasn't needed
1997 if (to_dealloc_id != NULL) {
1998 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1999 }
2000 }
2001 return id;
2002 }
2003
2004 // Figure out how many jmethodIDs haven't been allocated, and make
2005 // sure space for them is pre-allocated. This makes getting all
2006 // method ids much, much faster with classes with more than 8
2007 // methods, and has a *substantial* effect on performance with jvmti
2008 // code that loads all jmethodIDs for all classes.
2009 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2010 int new_jmeths = 0;
2011 int length = methods()->length();
2012 for (int index = start_offset; index < length; index++) {
2013 Method* m = methods()->at(index);
2014 jmethodID id = m->find_jmethod_id_or_null();
2015 if (id == NULL) {
2016 new_jmeths++;
2017 }
2018 }
2019 if (new_jmeths != 0) {
2020 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2021 }
2022 }
2023
2024 // Common code to fetch the jmethodID from the cache or update the
2025 // cache with the new jmethodID. This function should never do anything
2026 // that causes the caller to go to a safepoint or we can deadlock with
2027 // the VMThread or have cache consistency issues.
2028 //
2029 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2030 size_t idnum, jmethodID new_id,
2031 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2032 jmethodID** to_dealloc_jmeths_p) {
2033 assert(new_id != NULL, "sanity check");
2034 assert(to_dealloc_id_p != NULL, "sanity check");
2035 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2036 assert(Threads::number_of_threads() == 0 ||
2037 SafepointSynchronize::is_at_safepoint() ||
2038 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2039
2040 // reacquire the cache - we are locked, single threaded or at a safepoint
2041 jmethodID* jmeths = methods_jmethod_ids_acquire();
2042 jmethodID id = NULL;
2043 size_t length = 0;
2044
2045 if (jmeths == NULL || // no cache yet
2046 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2047 if (jmeths != NULL) {
2048 // copy any existing entries from the old cache
2049 for (size_t index = 0; index < length; index++) {
2050 new_jmeths[index+1] = jmeths[index+1];
2051 }
2052 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2053 }
2054 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2055 } else {
2056 // fetch jmethodID (if any) from the existing cache
2057 id = jmeths[idnum+1];
2058 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2059 }
2060 if (id == NULL) {
2061 // No matching jmethodID in the existing cache or we have a new
2062 // cache or we just grew the cache. This cache write is done here
2063 // by the first thread to win the foot race because a jmethodID
2064 // needs to be unique once it is generally available.
2065 id = new_id;
2066
2067 // The jmethodID cache can be read while unlocked so we have to
2068 // make sure the new jmethodID is complete before installing it
2069 // in the cache.
2070 OrderAccess::release_store(&jmeths[idnum+1], id);
2071 } else {
2072 *to_dealloc_id_p = new_id; // save new id for later delete
2073 }
2074 return id;
2075 }
2076
2077
2078 // Common code to get the jmethodID cache length and the jmethodID
2079 // value at index idnum if there is one.
2080 //
2081 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2082 size_t idnum, size_t *length_p, jmethodID* id_p) {
2083 assert(cache != NULL, "sanity check");
2084 assert(length_p != NULL, "sanity check");
2085 assert(id_p != NULL, "sanity check");
2086
2087 // cache size is stored in element[0], other elements offset by one
2088 *length_p = (size_t)cache[0];
2089 if (*length_p <= idnum) { // cache is too short
2090 *id_p = NULL;
2091 } else {
2092 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2093 }
2094 }
2095
2096
2097 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2098 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2099 size_t idnum = (size_t)method->method_idnum();
2100 jmethodID* jmeths = methods_jmethod_ids_acquire();
2101 size_t length; // length assigned as debugging crumb
2102 jmethodID id = NULL;
2103 if (jmeths != NULL && // If there is a cache
2104 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2105 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2106 }
2107 return id;
2108 }
2109
2110 inline DependencyContext InstanceKlass::dependencies() {
2111 DependencyContext dep_context(&_dep_context);
2112 return dep_context;
2113 }
2114
2115 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2116 return dependencies().mark_dependent_nmethods(changes);
2117 }
2118
2119 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2120 dependencies().add_dependent_nmethod(nm);
2121 }
2122
2123 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2124 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2125 }
2126
2127 #ifndef PRODUCT
2128 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2129 dependencies().print_dependent_nmethods(verbose);
2130 }
2131
2132 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2133 return dependencies().is_dependent_nmethod(nm);
2134 }
2135 #endif //PRODUCT
2136
2137 void InstanceKlass::clean_weak_instanceklass_links() {
2138 clean_implementors_list();
2139 clean_method_data();
2140
2141 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2142 DependencyContext dep_context(&_dep_context);
2143 dep_context.expunge_stale_entries();
2144 }
2145
2146 void InstanceKlass::clean_implementors_list() {
2147 assert(is_loader_alive(), "this klass should be live");
2148 if (is_interface()) {
2149 assert (ClassUnloading, "only called for ClassUnloading");
2150 for (;;) {
2151 // Use load_acquire due to competing with inserts
2152 Klass* impl = OrderAccess::load_acquire(adr_implementor());
2153 if (impl != NULL && !impl->is_loader_alive()) {
2154 // NULL this field, might be an unloaded klass or NULL
2155 Klass* volatile* klass = adr_implementor();
2156 if (Atomic::cmpxchg((Klass*)NULL, klass, impl) == impl) {
2157 // Successfully unlinking implementor.
2158 if (log_is_enabled(Trace, class, unload)) {
2159 ResourceMark rm;
2160 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2161 }
2162 return;
2163 }
2164 } else {
2165 return;
2166 }
2167 }
2168 }
2169 }
2170
2171 void InstanceKlass::clean_method_data() {
2172 for (int m = 0; m < methods()->length(); m++) {
2173 MethodData* mdo = methods()->at(m)->method_data();
2174 if (mdo != NULL) {
2175 mdo->clean_method_data(/*always_clean*/false);
2176 }
2177 }
2178 }
2179
2180 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2181 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2182 ResourceMark rm;
2183 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2184 return false;
2185 }
2186
2187 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2188 if (local_interfaces != NULL) {
2189 int length = local_interfaces->length();
2190 for (int i = 0; i < length; i++) {
2191 InstanceKlass* intf = local_interfaces->at(i);
2192 if (!intf->has_passed_fingerprint_check()) {
2193 ResourceMark rm;
2194 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2195 return false;
2196 }
2197 }
2198 }
2199
2200 return true;
2201 }
2202
2203 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2204 #if INCLUDE_AOT
2205 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2206 if (CalculateClassFingerprint) {
2207 // (1) We are running AOT to generate a shared library.
2208 return true;
2209 }
2210 if (DumpSharedSpaces) {
2211 // (2) We are running -Xshare:dump to create a shared archive
2212 return true;
2213 }
2214 if (UseAOT && is_unsafe_anonymous) {
2215 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2216 return true;
2217 }
2218 #endif
2219
2220 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2221 // but do not store the 64-bit fingerprint to save space.
2222 return false;
2223 }
2224
2225 bool InstanceKlass::has_stored_fingerprint() const {
2226 #if INCLUDE_AOT
2227 return should_store_fingerprint() || is_shared();
2228 #else
2229 return false;
2230 #endif
2231 }
2232
2233 uint64_t InstanceKlass::get_stored_fingerprint() const {
2234 address adr = adr_fingerprint();
2235 if (adr != NULL) {
2236 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2237 }
2238 return 0;
2239 }
2240
2241 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2242 address adr = adr_fingerprint();
2243 if (adr != NULL) {
2244 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2245
2246 ResourceMark rm;
2247 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2248 }
2249 }
2250
2251 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2252 Klass::metaspace_pointers_do(it);
2253
2254 if (log_is_enabled(Trace, cds)) {
2255 ResourceMark rm;
2256 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2257 }
2258
2259 it->push(&_annotations);
2260 it->push((Klass**)&_array_klasses);
2261 it->push(&_constants);
2262 it->push(&_inner_classes);
2263 it->push(&_array_name);
2264 #if INCLUDE_JVMTI
2265 it->push(&_previous_versions);
2266 #endif
2267 it->push(&_methods);
2268 it->push(&_default_methods);
2269 it->push(&_local_interfaces);
2270 it->push(&_transitive_interfaces);
2271 it->push(&_method_ordering);
2272 it->push(&_default_vtable_indices);
2273 it->push(&_fields);
2274
2275 if (itable_length() > 0) {
2276 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2277 int method_table_offset_in_words = ioe->offset()/wordSize;
2278 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2279 / itableOffsetEntry::size();
2280
2281 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2282 if (ioe->interface_klass() != NULL) {
2283 it->push(ioe->interface_klass_addr());
2284 itableMethodEntry* ime = ioe->first_method_entry(this);
2285 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2286 for (int index = 0; index < n; index ++) {
2287 it->push(ime[index].method_addr());
2288 }
2289 }
2290 }
2291 }
2292
2293 it->push(&_nest_members);
2294 }
2295
2296 void InstanceKlass::remove_unshareable_info() {
2297 Klass::remove_unshareable_info();
2298
2299 if (is_in_error_state()) {
2300 // Classes are attempted to link during dumping and may fail,
2301 // but these classes are still in the dictionary and class list in CLD.
2302 // Check in_error state first because in_error is > linked state, so
2303 // is_linked() is true.
2304 // If there's a linking error, there is nothing else to remove.
2305 return;
2306 }
2307
2308 // Reset to the 'allocated' state to prevent any premature accessing to
2309 // a shared class at runtime while the class is still being loaded and
2310 // restored. A class' init_state is set to 'loaded' at runtime when it's
2311 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2312 _init_state = allocated;
2313
2314 {
2315 MutexLocker ml(Compile_lock);
2316 init_implementor();
2317 }
2318
2319 constants()->remove_unshareable_info();
2320
2321 for (int i = 0; i < methods()->length(); i++) {
2322 Method* m = methods()->at(i);
2323 m->remove_unshareable_info();
2324 }
2325
2326 // do array classes also.
2327 if (array_klasses() != NULL) {
2328 array_klasses()->remove_unshareable_info();
2329 }
2330
2331 // These are not allocated from metaspace, but they should should all be empty
2332 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2333 guarantee(_source_debug_extension == NULL, "must be");
2334 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2335 guarantee(_osr_nmethods_head == NULL, "must be");
2336
2337 #if INCLUDE_JVMTI
2338 guarantee(_breakpoints == NULL, "must be");
2339 guarantee(_previous_versions == NULL, "must be");
2340 #endif
2341
2342 _init_thread = NULL;
2343 _methods_jmethod_ids = NULL;
2344 _jni_ids = NULL;
2345 _oop_map_cache = NULL;
2346 // clear _nest_host to ensure re-load at runtime
2347 _nest_host = NULL;
2348 }
2349
2350 void InstanceKlass::remove_java_mirror() {
2351 Klass::remove_java_mirror();
2352
2353 // do array classes also.
2354 if (array_klasses() != NULL) {
2355 array_klasses()->remove_java_mirror();
2356 }
2357 }
2358
2359 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2360 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2361 // before the InstanceKlass is added to the SystemDictionary. Make
2362 // sure the current state is <loaded.
2363 assert(!is_loaded(), "invalid init state");
2364 set_package(loader_data, CHECK);
2365 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2366
2367 Array<Method*>* methods = this->methods();
2368 int num_methods = methods->length();
2369 for (int index2 = 0; index2 < num_methods; ++index2) {
2370 methodHandle m(THREAD, methods->at(index2));
2371 m->restore_unshareable_info(CHECK);
2372 }
2373 if (JvmtiExport::has_redefined_a_class()) {
2374 // Reinitialize vtable because RedefineClasses may have changed some
2375 // entries in this vtable for super classes so the CDS vtable might
2376 // point to old or obsolete entries. RedefineClasses doesn't fix up
2377 // vtables in the shared system dictionary, only the main one.
2378 // It also redefines the itable too so fix that too.
2379 vtable().initialize_vtable(false, CHECK);
2380 itable().initialize_itable(false, CHECK);
2381 }
2382
2383 // restore constant pool resolved references
2384 constants()->restore_unshareable_info(CHECK);
2385
2386 if (array_klasses() != NULL) {
2387 // Array classes have null protection domain.
2388 // --> see ArrayKlass::complete_create_array_klass()
2389 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2390 }
2391 }
2392
2393 // returns true IFF is_in_error_state() has been changed as a result of this call.
2394 bool InstanceKlass::check_sharing_error_state() {
2395 assert(DumpSharedSpaces, "should only be called during dumping");
2396 bool old_state = is_in_error_state();
2397
2398 if (!is_in_error_state()) {
2399 bool bad = false;
2400 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2401 if (sup->is_in_error_state()) {
2402 bad = true;
2403 break;
2404 }
2405 }
2406 if (!bad) {
2407 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2408 for (int i = 0; i < interfaces->length(); i++) {
2409 InstanceKlass* iface = interfaces->at(i);
2410 if (iface->is_in_error_state()) {
2411 bad = true;
2412 break;
2413 }
2414 }
2415 }
2416
2417 if (bad) {
2418 set_in_error_state();
2419 }
2420 }
2421
2422 return (old_state != is_in_error_state());
2423 }
2424
2425 #if INCLUDE_JVMTI
2426 static void clear_all_breakpoints(Method* m) {
2427 m->clear_all_breakpoints();
2428 }
2429 #endif
2430
2431 void InstanceKlass::unload_class(InstanceKlass* ik) {
2432 // Release dependencies.
2433 ik->dependencies().remove_all_dependents();
2434
2435 // notify the debugger
2436 if (JvmtiExport::should_post_class_unload()) {
2437 JvmtiExport::post_class_unload(ik);
2438 }
2439
2440 // notify ClassLoadingService of class unload
2441 ClassLoadingService::notify_class_unloaded(ik);
2442
2443 #if INCLUDE_JFR
2444 assert(ik != NULL, "invariant");
2445 EventClassUnload event;
2446 event.set_unloadedClass(ik);
2447 event.set_definingClassLoader(ik->class_loader_data());
2448 event.commit();
2449 #endif
2450 }
2451
2452 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2453 // Clean up C heap
2454 ik->release_C_heap_structures();
2455 ik->constants()->release_C_heap_structures();
2456 }
2457
2458 void InstanceKlass::release_C_heap_structures() {
2459 // Can't release the constant pool here because the constant pool can be
2460 // deallocated separately from the InstanceKlass for default methods and
2461 // redefine classes.
2462
2463 // Deallocate oop map cache
2464 if (_oop_map_cache != NULL) {
2465 delete _oop_map_cache;
2466 _oop_map_cache = NULL;
2467 }
2468
2469 // Deallocate JNI identifiers for jfieldIDs
2470 JNIid::deallocate(jni_ids());
2471 set_jni_ids(NULL);
2472
2473 jmethodID* jmeths = methods_jmethod_ids_acquire();
2474 if (jmeths != (jmethodID*)NULL) {
2475 release_set_methods_jmethod_ids(NULL);
2476 FreeHeap(jmeths);
2477 }
2478
2479 assert(_dep_context == DependencyContext::EMPTY,
2480 "dependencies should already be cleaned");
2481
2482 #if INCLUDE_JVMTI
2483 // Deallocate breakpoint records
2484 if (breakpoints() != 0x0) {
2485 methods_do(clear_all_breakpoints);
2486 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2487 }
2488
2489 // deallocate the cached class file
2490 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2491 os::free(_cached_class_file);
2492 _cached_class_file = NULL;
2493 }
2494 #endif
2495
2496 // Decrement symbol reference counts associated with the unloaded class.
2497 if (_name != NULL) _name->decrement_refcount();
2498 // unreference array name derived from this class name (arrays of an unloaded
2499 // class can't be referenced anymore).
2500 if (_array_name != NULL) _array_name->decrement_refcount();
2501 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2502 }
2503
2504 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2505 if (array == NULL) {
2506 _source_debug_extension = NULL;
2507 } else {
2508 // Adding one to the attribute length in order to store a null terminator
2509 // character could cause an overflow because the attribute length is
2510 // already coded with an u4 in the classfile, but in practice, it's
2511 // unlikely to happen.
2512 assert((length+1) > length, "Overflow checking");
2513 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2514 for (int i = 0; i < length; i++) {
2515 sde[i] = array[i];
2516 }
2517 sde[length] = '\0';
2518 _source_debug_extension = sde;
2519 }
2520 }
2521
2522 const char* InstanceKlass::signature_name() const {
2523 int hash_len = 0;
2524 char hash_buf[40];
2525
2526 // If this is an unsafe anonymous class, append a hash to make the name unique
2527 if (is_unsafe_anonymous()) {
2528 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2529 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2530 hash_len = (int)strlen(hash_buf);
2531 }
2532
2533 // Get the internal name as a c string
2534 const char* src = (const char*) (name()->as_C_string());
2535 const int src_length = (int)strlen(src);
2536
2537 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2538
2539 // Add L as type indicator
2540 int dest_index = 0;
2541 dest[dest_index++] = 'L';
2542
2543 // Add the actual class name
2544 for (int src_index = 0; src_index < src_length; ) {
2545 dest[dest_index++] = src[src_index++];
2546 }
2547
2548 // If we have a hash, append it
2549 for (int hash_index = 0; hash_index < hash_len; ) {
2550 dest[dest_index++] = hash_buf[hash_index++];
2551 }
2552
2553 // Add the semicolon and the NULL
2554 dest[dest_index++] = ';';
2555 dest[dest_index] = '\0';
2556 return dest;
2557 }
2558
2559 // Used to obtain the package name from a fully qualified class name.
2560 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2561 if (name == NULL) {
2562 return NULL;
2563 } else {
2564 if (name->utf8_length() <= 0) {
2565 return NULL;
2566 }
2567 ResourceMark rm;
2568 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2569 if (package_name == NULL) {
2570 return NULL;
2571 }
2572 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2573 return pkg_name;
2574 }
2575 }
2576
2577 ModuleEntry* InstanceKlass::module() const {
2578 // For an unsafe anonymous class return the host class' module
2579 if (is_unsafe_anonymous()) {
2580 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2581 return unsafe_anonymous_host()->module();
2582 }
2583
2584 // Class is in a named package
2585 if (!in_unnamed_package()) {
2586 return _package_entry->module();
2587 }
2588
2589 // Class is in an unnamed package, return its loader's unnamed module
2590 return class_loader_data()->unnamed_module();
2591 }
2592
2593 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2594
2595 // ensure java/ packages only loaded by boot or platform builtin loaders
2596 check_prohibited_package(name(), loader_data, CHECK);
2597
2598 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2599
2600 if (pkg_name != NULL && loader_data != NULL) {
2601
2602 // Find in class loader's package entry table.
2603 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2604
2605 // If the package name is not found in the loader's package
2606 // entry table, it is an indication that the package has not
2607 // been defined. Consider it defined within the unnamed module.
2608 if (_package_entry == NULL) {
2609 ResourceMark rm;
2610
2611 if (!ModuleEntryTable::javabase_defined()) {
2612 // Before java.base is defined during bootstrapping, define all packages in
2613 // the java.base module. If a non-java.base package is erroneously placed
2614 // in the java.base module it will be caught later when java.base
2615 // is defined by ModuleEntryTable::verify_javabase_packages check.
2616 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2617 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2618 } else {
2619 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2620 _package_entry = loader_data->packages()->lookup(pkg_name,
2621 loader_data->unnamed_module());
2622 }
2623
2624 // A package should have been successfully created
2625 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2626 name()->as_C_string(), loader_data->loader_name_and_id());
2627 }
2628
2629 if (log_is_enabled(Debug, module)) {
2630 ResourceMark rm;
2631 ModuleEntry* m = _package_entry->module();
2632 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2633 external_name(),
2634 pkg_name->as_C_string(),
2635 loader_data->loader_name_and_id(),
2636 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2637 }
2638 } else {
2639 ResourceMark rm;
2640 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2641 external_name(),
2642 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2643 UNNAMED_MODULE);
2644 }
2645 }
2646
2647
2648 // different versions of is_same_class_package
2649
2650 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2651 oop classloader1 = this->class_loader();
2652 PackageEntry* classpkg1 = this->package();
2653 if (class2->is_objArray_klass()) {
2654 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2655 }
2656
2657 oop classloader2;
2658 PackageEntry* classpkg2;
2659 if (class2->is_instance_klass()) {
2660 classloader2 = class2->class_loader();
2661 classpkg2 = class2->package();
2662 } else {
2663 assert(class2->is_typeArray_klass(), "should be type array");
2664 classloader2 = NULL;
2665 classpkg2 = NULL;
2666 }
2667
2668 // Same package is determined by comparing class loader
2669 // and package entries. Both must be the same. This rule
2670 // applies even to classes that are defined in the unnamed
2671 // package, they still must have the same class loader.
2672 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2673 return true;
2674 }
2675
2676 return false;
2677 }
2678
2679 // return true if this class and other_class are in the same package. Classloader
2680 // and classname information is enough to determine a class's package
2681 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2682 const Symbol* other_class_name) const {
2683 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2684 return false;
2685 }
2686 if (name()->fast_compare(other_class_name) == 0) {
2687 return true;
2688 }
2689
2690 {
2691 ResourceMark rm;
2692
2693 bool bad_class_name = false;
2694 const char* other_pkg =
2695 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2696 if (bad_class_name) {
2697 return false;
2698 }
2699 // Check that package_from_name() returns NULL, not "", if there is no package.
2700 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2701
2702 const Symbol* const this_package_name =
2703 this->package() != NULL ? this->package()->name() : NULL;
2704
2705 if (this_package_name == NULL || other_pkg == NULL) {
2706 // One of the two doesn't have a package. Only return true if the other
2707 // one also doesn't have a package.
2708 return (const char*)this_package_name == other_pkg;
2709 }
2710
2711 // Check if package is identical
2712 return this_package_name->equals(other_pkg);
2713 }
2714 }
2715
2716 // Returns true iff super_method can be overridden by a method in targetclassname
2717 // See JLS 3rd edition 8.4.6.1
2718 // Assumes name-signature match
2719 // "this" is InstanceKlass of super_method which must exist
2720 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2721 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2722 // Private methods can not be overridden
2723 if (super_method->is_private()) {
2724 return false;
2725 }
2726 // If super method is accessible, then override
2727 if ((super_method->is_protected()) ||
2728 (super_method->is_public())) {
2729 return true;
2730 }
2731 // Package-private methods are not inherited outside of package
2732 assert(super_method->is_package_private(), "must be package private");
2733 return(is_same_class_package(targetclassloader(), targetclassname));
2734 }
2735
2736 // Only boot and platform class loaders can define classes in "java/" packages.
2737 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2738 ClassLoaderData* loader_data,
2739 TRAPS) {
2740 if (!loader_data->is_boot_class_loader_data() &&
2741 !loader_data->is_platform_class_loader_data() &&
2742 class_name != NULL) {
2743 ResourceMark rm(THREAD);
2744 char* name = class_name->as_C_string();
2745 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2746 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2747 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2748 name = pkg_name->as_C_string();
2749 const char* class_loader_name = loader_data->loader_name_and_id();
2750 StringUtils::replace_no_expand(name, "/", ".");
2751 const char* msg_text1 = "Class loader (instance of): ";
2752 const char* msg_text2 = " tried to load prohibited package name: ";
2753 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2754 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2755 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2756 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2757 }
2758 }
2759 return;
2760 }
2761
2762 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2763 constantPoolHandle i_cp(THREAD, constants());
2764 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2765 int ioff = iter.inner_class_info_index();
2766 if (ioff != 0) {
2767 // Check to see if the name matches the class we're looking for
2768 // before attempting to find the class.
2769 if (i_cp->klass_name_at_matches(this, ioff)) {
2770 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2771 if (this == inner_klass) {
2772 *ooff = iter.outer_class_info_index();
2773 *noff = iter.inner_name_index();
2774 return true;
2775 }
2776 }
2777 }
2778 }
2779 return false;
2780 }
2781
2782 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2783 InstanceKlass* outer_klass = NULL;
2784 *inner_is_member = false;
2785 int ooff = 0, noff = 0;
2786 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2787 if (has_inner_classes_attr) {
2788 constantPoolHandle i_cp(THREAD, constants());
2789 if (ooff != 0) {
2790 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2791 outer_klass = InstanceKlass::cast(ok);
2792 *inner_is_member = true;
2793 }
2794 if (NULL == outer_klass) {
2795 // It may be unsafe anonymous; try for that.
2796 int encl_method_class_idx = enclosing_method_class_index();
2797 if (encl_method_class_idx != 0) {
2798 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2799 outer_klass = InstanceKlass::cast(ok);
2800 *inner_is_member = false;
2801 }
2802 }
2803 }
2804
2805 // If no inner class attribute found for this class.
2806 if (NULL == outer_klass) return NULL;
2807
2808 // Throws an exception if outer klass has not declared k as an inner klass
2809 // We need evidence that each klass knows about the other, or else
2810 // the system could allow a spoof of an inner class to gain access rights.
2811 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2812 return outer_klass;
2813 }
2814
2815 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2816 jint access = access_flags().as_int();
2817
2818 // But check if it happens to be member class.
2819 InnerClassesIterator iter(this);
2820 for (; !iter.done(); iter.next()) {
2821 int ioff = iter.inner_class_info_index();
2822 // Inner class attribute can be zero, skip it.
2823 // Strange but true: JVM spec. allows null inner class refs.
2824 if (ioff == 0) continue;
2825
2826 // only look at classes that are already loaded
2827 // since we are looking for the flags for our self.
2828 Symbol* inner_name = constants()->klass_name_at(ioff);
2829 if (name() == inner_name) {
2830 // This is really a member class.
2831 access = iter.inner_access_flags();
2832 break;
2833 }
2834 }
2835 // Remember to strip ACC_SUPER bit
2836 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2837 }
2838
2839 jint InstanceKlass::jvmti_class_status() const {
2840 jint result = 0;
2841
2842 if (is_linked()) {
2843 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2844 }
2845
2846 if (is_initialized()) {
2847 assert(is_linked(), "Class status is not consistent");
2848 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2849 }
2850 if (is_in_error_state()) {
2851 result |= JVMTI_CLASS_STATUS_ERROR;
2852 }
2853 return result;
2854 }
2855
2856 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2857 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2858 int method_table_offset_in_words = ioe->offset()/wordSize;
2859 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2860 / itableOffsetEntry::size();
2861
2862 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2863 // If the interface isn't implemented by the receiver class,
2864 // the VM should throw IncompatibleClassChangeError.
2865 if (cnt >= nof_interfaces) {
2866 ResourceMark rm(THREAD);
2867 stringStream ss;
2868 bool same_module = (module() == holder->module());
2869 ss.print("Receiver class %s does not implement "
2870 "the interface %s defining the method to be called "
2871 "(%s%s%s)",
2872 external_name(), holder->external_name(),
2873 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2874 (same_module) ? "" : "; ",
2875 (same_module) ? "" : holder->class_in_module_of_loader());
2876 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2877 }
2878
2879 Klass* ik = ioe->interface_klass();
2880 if (ik == holder) break;
2881 }
2882
2883 itableMethodEntry* ime = ioe->first_method_entry(this);
2884 Method* m = ime[index].method();
2885 if (m == NULL) {
2886 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2887 }
2888 return m;
2889 }
2890
2891
2892 #if INCLUDE_JVMTI
2893 // update default_methods for redefineclasses for methods that are
2894 // not yet in the vtable due to concurrent subclass define and superinterface
2895 // redefinition
2896 // Note: those in the vtable, should have been updated via adjust_method_entries
2897 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2898 // search the default_methods for uses of either obsolete or EMCP methods
2899 if (default_methods() != NULL) {
2900 for (int index = 0; index < default_methods()->length(); index ++) {
2901 Method* old_method = default_methods()->at(index);
2902 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2903 continue; // skip uninteresting entries
2904 }
2905 assert(!old_method->is_deleted(), "default methods may not be deleted");
2906
2907 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2908
2909 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2910 assert(old_method != new_method, "sanity check");
2911
2912 default_methods()->at_put(index, new_method);
2913 if (log_is_enabled(Info, redefine, class, update)) {
2914 ResourceMark rm;
2915 if (!(*trace_name_printed)) {
2916 log_info(redefine, class, update)
2917 ("adjust: klassname=%s default methods from name=%s",
2918 external_name(), old_method->method_holder()->external_name());
2919 *trace_name_printed = true;
2920 }
2921 log_debug(redefine, class, update, vtables)
2922 ("default method update: %s(%s) ",
2923 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2924 }
2925 }
2926 }
2927 }
2928 #endif // INCLUDE_JVMTI
2929
2930 // On-stack replacement stuff
2931 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2932 // only one compilation can be active
2933 {
2934 // This is a short non-blocking critical region, so the no safepoint check is ok.
2935 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2936 assert(n->is_osr_method(), "wrong kind of nmethod");
2937 n->set_osr_link(osr_nmethods_head());
2938 set_osr_nmethods_head(n);
2939 // Raise the highest osr level if necessary
2940 if (TieredCompilation) {
2941 Method* m = n->method();
2942 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2943 }
2944 }
2945
2946 // Get rid of the osr methods for the same bci that have lower levels.
2947 if (TieredCompilation) {
2948 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2949 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2950 if (inv != NULL && inv->is_in_use()) {
2951 inv->make_not_entrant();
2952 }
2953 }
2954 }
2955 }
2956
2957 // Remove osr nmethod from the list. Return true if found and removed.
2958 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2959 // This is a short non-blocking critical region, so the no safepoint check is ok.
2960 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2961 assert(n->is_osr_method(), "wrong kind of nmethod");
2962 nmethod* last = NULL;
2963 nmethod* cur = osr_nmethods_head();
2964 int max_level = CompLevel_none; // Find the max comp level excluding n
2965 Method* m = n->method();
2966 // Search for match
2967 bool found = false;
2968 while(cur != NULL && cur != n) {
2969 if (TieredCompilation && m == cur->method()) {
2970 // Find max level before n
2971 max_level = MAX2(max_level, cur->comp_level());
2972 }
2973 last = cur;
2974 cur = cur->osr_link();
2975 }
2976 nmethod* next = NULL;
2977 if (cur == n) {
2978 found = true;
2979 next = cur->osr_link();
2980 if (last == NULL) {
2981 // Remove first element
2982 set_osr_nmethods_head(next);
2983 } else {
2984 last->set_osr_link(next);
2985 }
2986 }
2987 n->set_osr_link(NULL);
2988 if (TieredCompilation) {
2989 cur = next;
2990 while (cur != NULL) {
2991 // Find max level after n
2992 if (m == cur->method()) {
2993 max_level = MAX2(max_level, cur->comp_level());
2994 }
2995 cur = cur->osr_link();
2996 }
2997 m->set_highest_osr_comp_level(max_level);
2998 }
2999 return found;
3000 }
3001
3002 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3003 // This is a short non-blocking critical region, so the no safepoint check is ok.
3004 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3005 nmethod* osr = osr_nmethods_head();
3006 int found = 0;
3007 while (osr != NULL) {
3008 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3009 if (osr->method() == m) {
3010 osr->mark_for_deoptimization();
3011 found++;
3012 }
3013 osr = osr->osr_link();
3014 }
3015 return found;
3016 }
3017
3018 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3019 // This is a short non-blocking critical region, so the no safepoint check is ok.
3020 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3021 nmethod* osr = osr_nmethods_head();
3022 nmethod* best = NULL;
3023 while (osr != NULL) {
3024 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3025 // There can be a time when a c1 osr method exists but we are waiting
3026 // for a c2 version. When c2 completes its osr nmethod we will trash
3027 // the c1 version and only be able to find the c2 version. However
3028 // while we overflow in the c1 code at back branches we don't want to
3029 // try and switch to the same code as we are already running
3030
3031 if (osr->method() == m &&
3032 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3033 if (match_level) {
3034 if (osr->comp_level() == comp_level) {
3035 // Found a match - return it.
3036 return osr;
3037 }
3038 } else {
3039 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3040 if (osr->comp_level() == CompLevel_highest_tier) {
3041 // Found the best possible - return it.
3042 return osr;
3043 }
3044 best = osr;
3045 }
3046 }
3047 }
3048 osr = osr->osr_link();
3049 }
3050 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3051 return best;
3052 }
3053 return NULL;
3054 }
3055
3056 // -----------------------------------------------------------------------------------------------------
3057 // Printing
3058
3059 #ifndef PRODUCT
3060
3061 #define BULLET " - "
3062
3063 static const char* state_names[] = {
3064 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3065 };
3066
3067 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3068 for (int i = 0; i < len; i++) {
3069 intptr_t e = start[i];
3070 st->print("%d : " INTPTR_FORMAT, i, e);
3071 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3072 st->print(" ");
3073 ((Metadata*)e)->print_value_on(st);
3074 }
3075 st->cr();
3076 }
3077 }
3078
3079 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3080 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3081 }
3082
3083 void InstanceKlass::print_on(outputStream* st) const {
3084 assert(is_klass(), "must be klass");
3085 Klass::print_on(st);
3086
3087 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3088 st->print(BULLET"klass size: %d", size()); st->cr();
3089 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3090 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3091 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3092 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3093 st->print(BULLET"sub: ");
3094 Klass* sub = subklass();
3095 int n;
3096 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3097 if (n < MaxSubklassPrintSize) {
3098 sub->print_value_on(st);
3099 st->print(" ");
3100 }
3101 }
3102 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3103 st->cr();
3104
3105 if (is_interface()) {
3106 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3107 if (nof_implementors() == 1) {
3108 st->print_cr(BULLET"implementor: ");
3109 st->print(" ");
3110 implementor()->print_value_on(st);
3111 st->cr();
3112 }
3113 }
3114
3115 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3116 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3117 if (Verbose || WizardMode) {
3118 Array<Method*>* method_array = methods();
3119 for (int i = 0; i < method_array->length(); i++) {
3120 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3121 }
3122 }
3123 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3124 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3125 if (Verbose && default_methods() != NULL) {
3126 Array<Method*>* method_array = default_methods();
3127 for (int i = 0; i < method_array->length(); i++) {
3128 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3129 }
3130 }
3131 if (default_vtable_indices() != NULL) {
3132 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3133 }
3134 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3135 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3136 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3137 if (class_loader_data() != NULL) {
3138 st->print(BULLET"class loader data: ");
3139 class_loader_data()->print_value_on(st);
3140 st->cr();
3141 }
3142 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3143 if (source_file_name() != NULL) {
3144 st->print(BULLET"source file: ");
3145 source_file_name()->print_value_on(st);
3146 st->cr();
3147 }
3148 if (source_debug_extension() != NULL) {
3149 st->print(BULLET"source debug extension: ");
3150 st->print("%s", source_debug_extension());
3151 st->cr();
3152 }
3153 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3154 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3155 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3156 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3157 {
3158 bool have_pv = false;
3159 // previous versions are linked together through the InstanceKlass
3160 for (InstanceKlass* pv_node = previous_versions();
3161 pv_node != NULL;
3162 pv_node = pv_node->previous_versions()) {
3163 if (!have_pv)
3164 st->print(BULLET"previous version: ");
3165 have_pv = true;
3166 pv_node->constants()->print_value_on(st);
3167 }
3168 if (have_pv) st->cr();
3169 }
3170
3171 if (generic_signature() != NULL) {
3172 st->print(BULLET"generic signature: ");
3173 generic_signature()->print_value_on(st);
3174 st->cr();
3175 }
3176 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3177 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3178 if (java_mirror() != NULL) {
3179 st->print(BULLET"java mirror: ");
3180 java_mirror()->print_value_on(st);
3181 st->cr();
3182 } else {
3183 st->print_cr(BULLET"java mirror: NULL");
3184 }
3185 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3186 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3187 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3188 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3189 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3190 FieldPrinter print_static_field(st);
3191 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3192 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3193 FieldPrinter print_nonstatic_field(st);
3194 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3195 ik->do_nonstatic_fields(&print_nonstatic_field);
3196
3197 st->print(BULLET"non-static oop maps: ");
3198 OopMapBlock* map = start_of_nonstatic_oop_maps();
3199 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3200 while (map < end_map) {
3201 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3202 map++;
3203 }
3204 st->cr();
3205 }
3206
3207 #endif //PRODUCT
3208
3209 void InstanceKlass::print_value_on(outputStream* st) const {
3210 assert(is_klass(), "must be klass");
3211 if (Verbose || WizardMode) access_flags().print_on(st);
3212 name()->print_value_on(st);
3213 }
3214
3215 #ifndef PRODUCT
3216
3217 void FieldPrinter::do_field(fieldDescriptor* fd) {
3218 _st->print(BULLET);
3219 if (_obj == NULL) {
3220 fd->print_on(_st);
3221 _st->cr();
3222 } else {
3223 fd->print_on_for(_st, _obj);
3224 _st->cr();
3225 }
3226 }
3227
3228
3229 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3230 Klass::oop_print_on(obj, st);
3231
3232 if (this == SystemDictionary::String_klass()) {
3233 typeArrayOop value = java_lang_String::value(obj);
3234 juint length = java_lang_String::length(obj);
3235 if (value != NULL &&
3236 value->is_typeArray() &&
3237 length <= (juint) value->length()) {
3238 st->print(BULLET"string: ");
3239 java_lang_String::print(obj, st);
3240 st->cr();
3241 if (!WizardMode) return; // that is enough
3242 }
3243 }
3244
3245 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3246 FieldPrinter print_field(st, obj);
3247 do_nonstatic_fields(&print_field);
3248
3249 if (this == SystemDictionary::Class_klass()) {
3250 st->print(BULLET"signature: ");
3251 java_lang_Class::print_signature(obj, st);
3252 st->cr();
3253 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3254 st->print(BULLET"fake entry for mirror: ");
3255 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3256 st->cr();
3257 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3258 st->print(BULLET"fake entry for array: ");
3259 Metadata::print_value_on_maybe_null(st, array_klass);
3260 st->cr();
3261 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3262 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3263 Klass* real_klass = java_lang_Class::as_Klass(obj);
3264 if (real_klass != NULL && real_klass->is_instance_klass()) {
3265 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3266 }
3267 } else if (this == SystemDictionary::MethodType_klass()) {
3268 st->print(BULLET"signature: ");
3269 java_lang_invoke_MethodType::print_signature(obj, st);
3270 st->cr();
3271 }
3272 }
3273
3274 bool InstanceKlass::verify_itable_index(int i) {
3275 int method_count = klassItable::method_count_for_interface(this);
3276 assert(i >= 0 && i < method_count, "index out of bounds");
3277 return true;
3278 }
3279
3280 #endif //PRODUCT
3281
3282 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3283 st->print("a ");
3284 name()->print_value_on(st);
3285 obj->print_address_on(st);
3286 if (this == SystemDictionary::String_klass()
3287 && java_lang_String::value(obj) != NULL) {
3288 ResourceMark rm;
3289 int len = java_lang_String::length(obj);
3290 int plen = (len < 24 ? len : 12);
3291 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3292 st->print(" = \"%s\"", str);
3293 if (len > plen)
3294 st->print("...[%d]", len);
3295 } else if (this == SystemDictionary::Class_klass()) {
3296 Klass* k = java_lang_Class::as_Klass(obj);
3297 st->print(" = ");
3298 if (k != NULL) {
3299 k->print_value_on(st);
3300 } else {
3301 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3302 st->print("%s", tname ? tname : "type?");
3303 }
3304 } else if (this == SystemDictionary::MethodType_klass()) {
3305 st->print(" = ");
3306 java_lang_invoke_MethodType::print_signature(obj, st);
3307 } else if (java_lang_boxing_object::is_instance(obj)) {
3308 st->print(" = ");
3309 java_lang_boxing_object::print(obj, st);
3310 } else if (this == SystemDictionary::LambdaForm_klass()) {
3311 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3312 if (vmentry != NULL) {
3313 st->print(" => ");
3314 vmentry->print_value_on(st);
3315 }
3316 } else if (this == SystemDictionary::MemberName_klass()) {
3317 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3318 if (vmtarget != NULL) {
3319 st->print(" = ");
3320 vmtarget->print_value_on(st);
3321 } else {
3322 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3323 st->print(".");
3324 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3325 }
3326 }
3327 }
3328
3329 const char* InstanceKlass::internal_name() const {
3330 return external_name();
3331 }
3332
3333 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3334 const char* module_name,
3335 const ClassFileStream* cfs) const {
3336 if (!log_is_enabled(Info, class, load)) {
3337 return;
3338 }
3339
3340 ResourceMark rm;
3341 LogMessage(class, load) msg;
3342 stringStream info_stream;
3343
3344 // Name and class hierarchy info
3345 info_stream.print("%s", external_name());
3346
3347 // Source
3348 if (cfs != NULL) {
3349 if (cfs->source() != NULL) {
3350 if (module_name != NULL) {
3351 if (ClassLoader::is_modules_image(cfs->source())) {
3352 info_stream.print(" source: jrt:/%s", module_name);
3353 } else {
3354 info_stream.print(" source: %s", cfs->source());
3355 }
3356 } else {
3357 info_stream.print(" source: %s", cfs->source());
3358 }
3359 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3360 Thread* THREAD = Thread::current();
3361 Klass* caller =
3362 THREAD->is_Java_thread()
3363 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3364 : NULL;
3365 // caller can be NULL, for example, during a JVMTI VM_Init hook
3366 if (caller != NULL) {
3367 info_stream.print(" source: instance of %s", caller->external_name());
3368 } else {
3369 // source is unknown
3370 }
3371 } else {
3372 oop class_loader = loader_data->class_loader();
3373 info_stream.print(" source: %s", class_loader->klass()->external_name());
3374 }
3375 } else {
3376 info_stream.print(" source: shared objects file");
3377 }
3378
3379 msg.info("%s", info_stream.as_string());
3380
3381 if (log_is_enabled(Debug, class, load)) {
3382 stringStream debug_stream;
3383
3384 // Class hierarchy info
3385 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3386 p2i(this), p2i(superklass()));
3387
3388 // Interfaces
3389 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3390 debug_stream.print(" interfaces:");
3391 int length = local_interfaces()->length();
3392 for (int i = 0; i < length; i++) {
3393 debug_stream.print(" " INTPTR_FORMAT,
3394 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3395 }
3396 }
3397
3398 // Class loader
3399 debug_stream.print(" loader: [");
3400 loader_data->print_value_on(&debug_stream);
3401 debug_stream.print("]");
3402
3403 // Classfile checksum
3404 if (cfs) {
3405 debug_stream.print(" bytes: %d checksum: %08x",
3406 cfs->length(),
3407 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3408 cfs->length()));
3409 }
3410
3411 msg.debug("%s", debug_stream.as_string());
3412 }
3413 }
3414
3415 #if INCLUDE_SERVICES
3416 // Size Statistics
3417 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3418 Klass::collect_statistics(sz);
3419
3420 sz->_inst_size = wordSize * size_helper();
3421 sz->_vtab_bytes = wordSize * vtable_length();
3422 sz->_itab_bytes = wordSize * itable_length();
3423 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3424
3425 int n = 0;
3426 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3427 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3428 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3429 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3430 n += (sz->_fields_bytes = sz->count_array(fields()));
3431 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3432 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3433 sz->_ro_bytes += n;
3434
3435 const ConstantPool* cp = constants();
3436 if (cp) {
3437 cp->collect_statistics(sz);
3438 }
3439
3440 const Annotations* anno = annotations();
3441 if (anno) {
3442 anno->collect_statistics(sz);
3443 }
3444
3445 const Array<Method*>* methods_array = methods();
3446 if (methods()) {
3447 for (int i = 0; i < methods_array->length(); i++) {
3448 Method* method = methods_array->at(i);
3449 if (method) {
3450 sz->_method_count ++;
3451 method->collect_statistics(sz);
3452 }
3453 }
3454 }
3455 }
3456 #endif // INCLUDE_SERVICES
3457
3458 // Verification
3459
3460 class VerifyFieldClosure: public BasicOopIterateClosure {
3461 protected:
3462 template <class T> void do_oop_work(T* p) {
3463 oop obj = RawAccess<>::oop_load(p);
3464 if (!oopDesc::is_oop_or_null(obj)) {
3465 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3466 Universe::print_on(tty);
3467 guarantee(false, "boom");
3468 }
3469 }
3470 public:
3471 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3472 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3473 };
3474
3475 void InstanceKlass::verify_on(outputStream* st) {
3476 #ifndef PRODUCT
3477 // Avoid redundant verifies, this really should be in product.
3478 if (_verify_count == Universe::verify_count()) return;
3479 _verify_count = Universe::verify_count();
3480 #endif
3481
3482 // Verify Klass
3483 Klass::verify_on(st);
3484
3485 // Verify that klass is present in ClassLoaderData
3486 guarantee(class_loader_data()->contains_klass(this),
3487 "this class isn't found in class loader data");
3488
3489 // Verify vtables
3490 if (is_linked()) {
3491 // $$$ This used to be done only for m/s collections. Doing it
3492 // always seemed a valid generalization. (DLD -- 6/00)
3493 vtable().verify(st);
3494 }
3495
3496 // Verify first subklass
3497 if (subklass() != NULL) {
3498 guarantee(subklass()->is_klass(), "should be klass");
3499 }
3500
3501 // Verify siblings
3502 Klass* super = this->super();
3503 Klass* sib = next_sibling();
3504 if (sib != NULL) {
3505 if (sib == this) {
3506 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3507 }
3508
3509 guarantee(sib->is_klass(), "should be klass");
3510 guarantee(sib->super() == super, "siblings should have same superklass");
3511 }
3512
3513 // Verify local interfaces
3514 if (local_interfaces()) {
3515 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3516 for (int j = 0; j < local_interfaces->length(); j++) {
3517 InstanceKlass* e = local_interfaces->at(j);
3518 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3519 }
3520 }
3521
3522 // Verify transitive interfaces
3523 if (transitive_interfaces() != NULL) {
3524 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3525 for (int j = 0; j < transitive_interfaces->length(); j++) {
3526 InstanceKlass* e = transitive_interfaces->at(j);
3527 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3528 }
3529 }
3530
3531 // Verify methods
3532 if (methods() != NULL) {
3533 Array<Method*>* methods = this->methods();
3534 for (int j = 0; j < methods->length(); j++) {
3535 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3536 }
3537 for (int j = 0; j < methods->length() - 1; j++) {
3538 Method* m1 = methods->at(j);
3539 Method* m2 = methods->at(j + 1);
3540 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3541 }
3542 }
3543
3544 // Verify method ordering
3545 if (method_ordering() != NULL) {
3546 Array<int>* method_ordering = this->method_ordering();
3547 int length = method_ordering->length();
3548 if (JvmtiExport::can_maintain_original_method_order() ||
3549 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3550 guarantee(length == methods()->length(), "invalid method ordering length");
3551 jlong sum = 0;
3552 for (int j = 0; j < length; j++) {
3553 int original_index = method_ordering->at(j);
3554 guarantee(original_index >= 0, "invalid method ordering index");
3555 guarantee(original_index < length, "invalid method ordering index");
3556 sum += original_index;
3557 }
3558 // Verify sum of indices 0,1,...,length-1
3559 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3560 } else {
3561 guarantee(length == 0, "invalid method ordering length");
3562 }
3563 }
3564
3565 // Verify default methods
3566 if (default_methods() != NULL) {
3567 Array<Method*>* methods = this->default_methods();
3568 for (int j = 0; j < methods->length(); j++) {
3569 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3570 }
3571 for (int j = 0; j < methods->length() - 1; j++) {
3572 Method* m1 = methods->at(j);
3573 Method* m2 = methods->at(j + 1);
3574 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3575 }
3576 }
3577
3578 // Verify JNI static field identifiers
3579 if (jni_ids() != NULL) {
3580 jni_ids()->verify(this);
3581 }
3582
3583 // Verify other fields
3584 if (array_klasses() != NULL) {
3585 guarantee(array_klasses()->is_klass(), "should be klass");
3586 }
3587 if (constants() != NULL) {
3588 guarantee(constants()->is_constantPool(), "should be constant pool");
3589 }
3590 const Klass* anonymous_host = unsafe_anonymous_host();
3591 if (anonymous_host != NULL) {
3592 guarantee(anonymous_host->is_klass(), "should be klass");
3593 }
3594 }
3595
3596 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3597 Klass::oop_verify_on(obj, st);
3598 VerifyFieldClosure blk;
3599 obj->oop_iterate(&blk);
3600 }
3601
3602
3603 // JNIid class for jfieldIDs only
3604 // Note to reviewers:
3605 // These JNI functions are just moved over to column 1 and not changed
3606 // in the compressed oops workspace.
3607 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3608 _holder = holder;
3609 _offset = offset;
3610 _next = next;
3611 debug_only(_is_static_field_id = false;)
3612 }
3613
3614
3615 JNIid* JNIid::find(int offset) {
3616 JNIid* current = this;
3617 while (current != NULL) {
3618 if (current->offset() == offset) return current;
3619 current = current->next();
3620 }
3621 return NULL;
3622 }
3623
3624 void JNIid::deallocate(JNIid* current) {
3625 while (current != NULL) {
3626 JNIid* next = current->next();
3627 delete current;
3628 current = next;
3629 }
3630 }
3631
3632
3633 void JNIid::verify(Klass* holder) {
3634 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3635 int end_field_offset;
3636 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3637
3638 JNIid* current = this;
3639 while (current != NULL) {
3640 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3641 #ifdef ASSERT
3642 int o = current->offset();
3643 if (current->is_static_field_id()) {
3644 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3645 }
3646 #endif
3647 current = current->next();
3648 }
3649 }
3650
3651 #ifdef ASSERT
3652 void InstanceKlass::set_init_state(ClassState state) {
3653 bool good_state = is_shared() ? (_init_state <= state)
3654 : (_init_state < state);
3655 assert(good_state || state == allocated, "illegal state transition");
3656 _init_state = (u1)state;
3657 }
3658 #endif
3659
3660 #if INCLUDE_JVMTI
3661
3662 // RedefineClasses() support for previous versions
3663
3664 // Globally, there is at least one previous version of a class to walk
3665 // during class unloading, which is saved because old methods in the class
3666 // are still running. Otherwise the previous version list is cleaned up.
3667 bool InstanceKlass::_has_previous_versions = false;
3668
3669 // Returns true if there are previous versions of a class for class
3670 // unloading only. Also resets the flag to false. purge_previous_version
3671 // will set the flag to true if there are any left, i.e., if there's any
3672 // work to do for next time. This is to avoid the expensive code cache
3673 // walk in CLDG::clean_deallocate_lists().
3674 bool InstanceKlass::has_previous_versions_and_reset() {
3675 bool ret = _has_previous_versions;
3676 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3677 ret ? "true" : "false");
3678 _has_previous_versions = false;
3679 return ret;
3680 }
3681
3682 // Purge previous versions before adding new previous versions of the class and
3683 // during class unloading.
3684 void InstanceKlass::purge_previous_version_list() {
3685 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3686 assert(has_been_redefined(), "Should only be called for main class");
3687
3688 // Quick exit.
3689 if (previous_versions() == NULL) {
3690 return;
3691 }
3692
3693 // This klass has previous versions so see what we can cleanup
3694 // while it is safe to do so.
3695
3696 int deleted_count = 0; // leave debugging breadcrumbs
3697 int live_count = 0;
3698 ClassLoaderData* loader_data = class_loader_data();
3699 assert(loader_data != NULL, "should never be null");
3700
3701 ResourceMark rm;
3702 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3703
3704 // previous versions are linked together through the InstanceKlass
3705 InstanceKlass* pv_node = previous_versions();
3706 InstanceKlass* last = this;
3707 int version = 0;
3708
3709 // check the previous versions list
3710 for (; pv_node != NULL; ) {
3711
3712 ConstantPool* pvcp = pv_node->constants();
3713 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3714
3715 if (!pvcp->on_stack()) {
3716 // If the constant pool isn't on stack, none of the methods
3717 // are executing. Unlink this previous_version.
3718 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3719 // so will be deallocated during the next phase of class unloading.
3720 log_trace(redefine, class, iklass, purge)
3721 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3722 // For debugging purposes.
3723 pv_node->set_is_scratch_class();
3724 // Unlink from previous version list.
3725 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3726 InstanceKlass* next = pv_node->previous_versions();
3727 pv_node->link_previous_versions(NULL); // point next to NULL
3728 last->link_previous_versions(next);
3729 // Add to the deallocate list after unlinking
3730 loader_data->add_to_deallocate_list(pv_node);
3731 pv_node = next;
3732 deleted_count++;
3733 version++;
3734 continue;
3735 } else {
3736 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3737 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3738 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3739 live_count++;
3740 // found a previous version for next time we do class unloading
3741 _has_previous_versions = true;
3742 }
3743
3744 // At least one method is live in this previous version.
3745 // Reset dead EMCP methods not to get breakpoints.
3746 // All methods are deallocated when all of the methods for this class are no
3747 // longer running.
3748 Array<Method*>* method_refs = pv_node->methods();
3749 if (method_refs != NULL) {
3750 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3751 for (int j = 0; j < method_refs->length(); j++) {
3752 Method* method = method_refs->at(j);
3753
3754 if (!method->on_stack()) {
3755 // no breakpoints for non-running methods
3756 if (method->is_running_emcp()) {
3757 method->set_running_emcp(false);
3758 }
3759 } else {
3760 assert (method->is_obsolete() || method->is_running_emcp(),
3761 "emcp method cannot run after emcp bit is cleared");
3762 log_trace(redefine, class, iklass, purge)
3763 ("purge: %s(%s): prev method @%d in version @%d is alive",
3764 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3765 }
3766 }
3767 }
3768 // next previous version
3769 last = pv_node;
3770 pv_node = pv_node->previous_versions();
3771 version++;
3772 }
3773 log_trace(redefine, class, iklass, purge)
3774 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3775 }
3776
3777 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3778 int emcp_method_count) {
3779 int obsolete_method_count = old_methods->length() - emcp_method_count;
3780
3781 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3782 _previous_versions != NULL) {
3783 // We have a mix of obsolete and EMCP methods so we have to
3784 // clear out any matching EMCP method entries the hard way.
3785 int local_count = 0;
3786 for (int i = 0; i < old_methods->length(); i++) {
3787 Method* old_method = old_methods->at(i);
3788 if (old_method->is_obsolete()) {
3789 // only obsolete methods are interesting
3790 Symbol* m_name = old_method->name();
3791 Symbol* m_signature = old_method->signature();
3792
3793 // previous versions are linked together through the InstanceKlass
3794 int j = 0;
3795 for (InstanceKlass* prev_version = _previous_versions;
3796 prev_version != NULL;
3797 prev_version = prev_version->previous_versions(), j++) {
3798
3799 Array<Method*>* method_refs = prev_version->methods();
3800 for (int k = 0; k < method_refs->length(); k++) {
3801 Method* method = method_refs->at(k);
3802
3803 if (!method->is_obsolete() &&
3804 method->name() == m_name &&
3805 method->signature() == m_signature) {
3806 // The current RedefineClasses() call has made all EMCP
3807 // versions of this method obsolete so mark it as obsolete
3808 log_trace(redefine, class, iklass, add)
3809 ("%s(%s): flush obsolete method @%d in version @%d",
3810 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3811
3812 method->set_is_obsolete();
3813 break;
3814 }
3815 }
3816
3817 // The previous loop may not find a matching EMCP method, but
3818 // that doesn't mean that we can optimize and not go any
3819 // further back in the PreviousVersion generations. The EMCP
3820 // method for this generation could have already been made obsolete,
3821 // but there still may be an older EMCP method that has not
3822 // been made obsolete.
3823 }
3824
3825 if (++local_count >= obsolete_method_count) {
3826 // no more obsolete methods so bail out now
3827 break;
3828 }
3829 }
3830 }
3831 }
3832 }
3833
3834 // Save the scratch_class as the previous version if any of the methods are running.
3835 // The previous_versions are used to set breakpoints in EMCP methods and they are
3836 // also used to clean MethodData links to redefined methods that are no longer running.
3837 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3838 int emcp_method_count) {
3839 assert(Thread::current()->is_VM_thread(),
3840 "only VMThread can add previous versions");
3841
3842 ResourceMark rm;
3843 log_trace(redefine, class, iklass, add)
3844 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3845
3846 // Clean out old previous versions for this class
3847 purge_previous_version_list();
3848
3849 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3850 // a previous redefinition may be made obsolete by this redefinition.
3851 Array<Method*>* old_methods = scratch_class->methods();
3852 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3853
3854 // If the constant pool for this previous version of the class
3855 // is not marked as being on the stack, then none of the methods
3856 // in this previous version of the class are on the stack so
3857 // we don't need to add this as a previous version.
3858 ConstantPool* cp_ref = scratch_class->constants();
3859 if (!cp_ref->on_stack()) {
3860 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3861 // For debugging purposes.
3862 scratch_class->set_is_scratch_class();
3863 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3864 return;
3865 }
3866
3867 if (emcp_method_count != 0) {
3868 // At least one method is still running, check for EMCP methods
3869 for (int i = 0; i < old_methods->length(); i++) {
3870 Method* old_method = old_methods->at(i);
3871 if (!old_method->is_obsolete() && old_method->on_stack()) {
3872 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3873 // we can add breakpoints for it.
3874
3875 // We set the method->on_stack bit during safepoints for class redefinition
3876 // and use this bit to set the is_running_emcp bit.
3877 // After the safepoint, the on_stack bit is cleared and the running emcp
3878 // method may exit. If so, we would set a breakpoint in a method that
3879 // is never reached, but this won't be noticeable to the programmer.
3880 old_method->set_running_emcp(true);
3881 log_trace(redefine, class, iklass, add)
3882 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3883 } else if (!old_method->is_obsolete()) {
3884 log_trace(redefine, class, iklass, add)
3885 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3886 }
3887 }
3888 }
3889
3890 // Add previous version if any methods are still running.
3891 // Set has_previous_version flag for processing during class unloading.
3892 _has_previous_versions = true;
3893 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3894 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3895 scratch_class->link_previous_versions(previous_versions());
3896 link_previous_versions(scratch_class);
3897 } // end add_previous_version()
3898
3899 #endif // INCLUDE_JVMTI
3900
3901 Method* InstanceKlass::method_with_idnum(int idnum) {
3902 Method* m = NULL;
3903 if (idnum < methods()->length()) {
3904 m = methods()->at(idnum);
3905 }
3906 if (m == NULL || m->method_idnum() != idnum) {
3907 for (int index = 0; index < methods()->length(); ++index) {
3908 m = methods()->at(index);
3909 if (m->method_idnum() == idnum) {
3910 return m;
3911 }
3912 }
3913 // None found, return null for the caller to handle.
3914 return NULL;
3915 }
3916 return m;
3917 }
3918
3919
3920 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3921 if (idnum >= methods()->length()) {
3922 return NULL;
3923 }
3924 Method* m = methods()->at(idnum);
3925 if (m != NULL && m->orig_method_idnum() == idnum) {
3926 return m;
3927 }
3928 // Obsolete method idnum does not match the original idnum
3929 for (int index = 0; index < methods()->length(); ++index) {
3930 m = methods()->at(index);
3931 if (m->orig_method_idnum() == idnum) {
3932 return m;
3933 }
3934 }
3935 // None found, return null for the caller to handle.
3936 return NULL;
3937 }
3938
3939
3940 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3941 InstanceKlass* holder = get_klass_version(version);
3942 if (holder == NULL) {
3943 return NULL; // The version of klass is gone, no method is found
3944 }
3945 Method* method = holder->method_with_orig_idnum(idnum);
3946 return method;
3947 }
3948
3949 #if INCLUDE_JVMTI
3950 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3951 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3952 // Ignore the archived class stream data
3953 return NULL;
3954 } else {
3955 return _cached_class_file;
3956 }
3957 }
3958
3959 jint InstanceKlass::get_cached_class_file_len() {
3960 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3961 }
3962
3963 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3964 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3965 }
3966
3967 #if INCLUDE_CDS
3968 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3969 if (DumpSharedSpaces) {
3970 return _cached_class_file;
3971 } else {
3972 assert(this->is_shared(), "class should be shared");
3973 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3974 return _cached_class_file;
3975 } else {
3976 return NULL;
3977 }
3978 }
3979 }
3980 #endif
3981 #endif