1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/verifier.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/dependencyContext.hpp"
39 #include "compiler/compileBroker.hpp"
40 #include "gc/shared/collectedHeap.inline.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/heapInspection.hpp"
49 #include "memory/iterator.inline.hpp"
50 #include "memory/metadataFactory.hpp"
51 #include "memory/metaspaceClosure.hpp"
52 #include "memory/metaspaceShared.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "oops/fieldStreams.hpp"
56 #include "oops/instanceClassLoaderKlass.hpp"
57 #include "oops/instanceKlass.inline.hpp"
58 #include "oops/instanceMirrorKlass.hpp"
59 #include "oops/instanceOop.hpp"
60 #include "oops/klass.inline.hpp"
61 #include "oops/method.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.inline.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83 #if INCLUDE_JFR
84 #include "jfr/jfrEvents.hpp"
85 #endif
86
87
88 #ifdef DTRACE_ENABLED
89
90
91 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
92 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
93 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
94 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
95 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
96 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
97 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
98 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
99 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
100 { \
101 char* data = NULL; \
102 int len = 0; \
103 Symbol* clss_name = name(); \
104 if (clss_name != NULL) { \
105 data = (char*)clss_name->bytes(); \
106 len = clss_name->utf8_length(); \
107 } \
108 HOTSPOT_CLASS_INITIALIZATION_##type( \
109 data, len, (void*)class_loader(), thread_type); \
110 }
111
112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
113 { \
114 char* data = NULL; \
115 int len = 0; \
116 Symbol* clss_name = name(); \
117 if (clss_name != NULL) { \
118 data = (char*)clss_name->bytes(); \
119 len = clss_name->utf8_length(); \
120 } \
121 HOTSPOT_CLASS_INITIALIZATION_##type( \
122 data, len, (void*)class_loader(), thread_type, wait); \
123 }
124
125 #else // ndef DTRACE_ENABLED
126
127 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
128 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
129
130 #endif // ndef DTRACE_ENABLED
131
132 static inline bool is_class_loader(const Symbol* class_name,
133 const ClassFileParser& parser) {
134 assert(class_name != NULL, "invariant");
135
136 if (class_name == vmSymbols::java_lang_ClassLoader()) {
137 return true;
138 }
139
140 if (SystemDictionary::ClassLoader_klass_loaded()) {
141 const Klass* const super_klass = parser.super_klass();
142 if (super_klass != NULL) {
143 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
144 return true;
145 }
146 }
147 }
148 return false;
149 }
150
151 // called to verify that k is a member of this nest
152 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
153 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
154 if (log_is_enabled(Trace, class, nestmates)) {
155 ResourceMark rm(THREAD);
156 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
157 k->external_name(), this->external_name());
158 }
159 return false;
160 }
161
162 if (log_is_enabled(Trace, class, nestmates)) {
163 ResourceMark rm(THREAD);
164 log_trace(class, nestmates)("Checking nest membership of %s in %s",
165 k->external_name(), this->external_name());
166 }
167
168 // Check names first and if they match then check actual klass. This avoids
169 // resolving anything unnecessarily.
170 for (int i = 0; i < _nest_members->length(); i++) {
171 int cp_index = _nest_members->at(i);
172 Symbol* name = _constants->klass_name_at(cp_index);
173 if (name == k->name()) {
174 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
175
176 // names match so check actual klass - this may trigger class loading if
177 // it doesn't match (but that should be impossible)
178 Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
179 if (k2 == k) {
180 log_trace(class, nestmates)("- class is listed as a nest member");
181 return true;
182 } else {
183 // same name but different klass!
184 log_trace(class, nestmates)(" - klass comparison failed!");
185 // can't have different classes for the same name, so we're done
186 return false;
187 }
188 }
189 }
190 log_trace(class, nestmates)("- class is NOT a nest member!");
191 return false;
192 }
193
194 // Return nest-host class, resolving, validating and saving it if needed.
195 // In cases where this is called from a thread that can not do classloading
196 // (such as a native JIT thread) then we simply return NULL, which in turn
197 // causes the access check to return false. Such code will retry the access
198 // from a more suitable environment later.
199 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
200 InstanceKlass* nest_host_k = _nest_host;
201 if (nest_host_k == NULL) {
202 // need to resolve and save our nest-host class. This could be attempted
203 // concurrently but as the result is idempotent and we don't use the class
204 // then we do not need any synchronization beyond what is implicitly used
205 // during class loading.
206 if (_nest_host_index != 0) { // we have a real nest_host
207 // Before trying to resolve check if we're in a suitable context
208 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
209 if (log_is_enabled(Trace, class, nestmates)) {
210 ResourceMark rm(THREAD);
211 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
212 this->external_name());
213 }
214 return NULL;
215 }
216
217 if (log_is_enabled(Trace, class, nestmates)) {
218 ResourceMark rm(THREAD);
219 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
220 this->external_name(),
221 _constants->klass_name_at(_nest_host_index)->as_C_string());
222 }
223
224 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
225 if (HAS_PENDING_EXCEPTION) {
226 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
227 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
228 // throw a new CDNFE with the original as its cause, and a clear msg
229 ResourceMark rm(THREAD);
230 char buf[200];
231 CLEAR_PENDING_EXCEPTION;
232 jio_snprintf(buf, sizeof(buf),
233 "Unable to load nest-host class (%s) of %s",
234 _constants->klass_name_at(_nest_host_index)->as_C_string(),
235 this->external_name());
236 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
237 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
238 }
239 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
240 return NULL;
241 }
242
243 // A valid nest-host is an instance class in the current package that lists this
244 // class as a nest member. If any of these conditions are not met we post the
245 // requested exception type (if any) and return NULL
246
247 const char* error = NULL;
248
249 // JVMS 5.4.4 indicates package check comes first
250 if (is_same_class_package(k)) {
251
252 // Now check actual membership. We can't be a member if our "host" is
253 // not an instance class.
254 if (k->is_instance_klass()) {
255 nest_host_k = InstanceKlass::cast(k);
256
257 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
258 if (is_member) {
259 // save resolved nest-host value
260 _nest_host = nest_host_k;
261
262 if (log_is_enabled(Trace, class, nestmates)) {
263 ResourceMark rm(THREAD);
264 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
265 this->external_name(), k->external_name());
266 }
267 return nest_host_k;
268 }
269 }
270 error = "current type is not listed as a nest member";
271 } else {
272 error = "types are in different packages";
273 }
274
275 if (log_is_enabled(Trace, class, nestmates)) {
276 ResourceMark rm(THREAD);
277 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
278 this->external_name(),
279 k->external_name(),
280 error);
281 }
282
283 if (validationException != NULL) {
284 ResourceMark rm(THREAD);
285 Exceptions::fthrow(THREAD_AND_LOCATION,
286 validationException,
287 "Type %s is not a nest member of %s: %s",
288 this->external_name(),
289 k->external_name(),
290 error
291 );
292 }
293 return NULL;
294 } else {
295 if (log_is_enabled(Trace, class, nestmates)) {
296 ResourceMark rm(THREAD);
297 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
298 this->external_name());
299 }
300 // save resolved nest-host value
301 return (_nest_host = this);
302 }
303 }
304 return nest_host_k;
305 }
306
307 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
308 // or we are k's nest_host - all of which is covered by comparing the two
309 // resolved_nest_hosts
310 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
311
312 assert(this != k, "this should be handled by higher-level code");
313
314 // Per JVMS 5.4.4 we first resolve and validate the current class, then
315 // the target class k. Resolution exceptions will be passed on by upper
316 // layers. IncompatibleClassChangeErrors from membership validation failures
317 // will also be passed through.
318
319 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
320 InstanceKlass* cur_host = nest_host(icce, CHECK_false);
321 if (cur_host == NULL) {
322 return false;
323 }
324
325 Klass* k_nest_host = k->nest_host(icce, CHECK_false);
326 if (k_nest_host == NULL) {
327 return false;
328 }
329
330 bool access = (cur_host == k_nest_host);
331
332 if (log_is_enabled(Trace, class, nestmates)) {
333 ResourceMark rm(THREAD);
334 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
335 this->external_name(),
336 access ? "" : "NOT ",
337 k->external_name());
338 }
339
340 return access;
341 }
342
343 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
344 const int size = InstanceKlass::size(parser.vtable_size(),
345 parser.itable_size(),
346 nonstatic_oop_map_size(parser.total_oop_map_count()),
347 parser.is_interface(),
348 parser.is_unsafe_anonymous(),
349 should_store_fingerprint(parser.is_unsafe_anonymous()));
350
351 const Symbol* const class_name = parser.class_name();
352 assert(class_name != NULL, "invariant");
353 ClassLoaderData* loader_data = parser.loader_data();
354 assert(loader_data != NULL, "invariant");
355
356 InstanceKlass* ik;
357
358 // Allocation
359 if (REF_NONE == parser.reference_type()) {
360 if (class_name == vmSymbols::java_lang_Class()) {
361 // mirror
362 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
363 }
364 else if (is_class_loader(class_name, parser)) {
365 // class loader
366 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
367 } else {
368 // normal
369 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
370 }
371 } else {
372 // reference
373 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
374 }
375
376 // Check for pending exception before adding to the loader data and incrementing
377 // class count. Can get OOM here.
378 if (HAS_PENDING_EXCEPTION) {
379 return NULL;
380 }
381
382 return ik;
383 }
384
385
386 // copy method ordering from resource area to Metaspace
387 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
388 if (m != NULL) {
389 // allocate a new array and copy contents (memcpy?)
390 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
391 for (int i = 0; i < m->length(); i++) {
392 _method_ordering->at_put(i, m->at(i));
393 }
394 } else {
395 _method_ordering = Universe::the_empty_int_array();
396 }
397 }
398
399 // create a new array of vtable_indices for default methods
400 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
401 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
402 assert(default_vtable_indices() == NULL, "only create once");
403 set_default_vtable_indices(vtable_indices);
404 return vtable_indices;
405 }
406
407 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
408 Klass(id),
409 _nest_members(NULL),
410 _nest_host_index(0),
411 _nest_host(NULL),
412 _static_field_size(parser.static_field_size()),
413 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
414 _itable_len(parser.itable_size()),
415 _reference_type(parser.reference_type()) {
416 set_vtable_length(parser.vtable_size());
417 set_kind(kind);
418 set_access_flags(parser.access_flags());
419 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
420 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
421 false));
422
423 assert(NULL == _methods, "underlying memory not zeroed?");
424 assert(is_instance_klass(), "is layout incorrect?");
425 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
426 }
427
428 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
429 Array<Method*>* methods) {
430 if (methods != NULL && methods != Universe::the_empty_method_array() &&
431 !methods->is_shared()) {
432 for (int i = 0; i < methods->length(); i++) {
433 Method* method = methods->at(i);
434 if (method == NULL) continue; // maybe null if error processing
435 // Only want to delete methods that are not executing for RedefineClasses.
436 // The previous version will point to them so they're not totally dangling
437 assert (!method->on_stack(), "shouldn't be called with methods on stack");
438 MetadataFactory::free_metadata(loader_data, method);
439 }
440 MetadataFactory::free_array<Method*>(loader_data, methods);
441 }
442 }
443
444 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
445 const Klass* super_klass,
446 Array<InstanceKlass*>* local_interfaces,
447 Array<InstanceKlass*>* transitive_interfaces) {
448 // Only deallocate transitive interfaces if not empty, same as super class
449 // or same as local interfaces. See code in parseClassFile.
450 Array<InstanceKlass*>* ti = transitive_interfaces;
451 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
452 // check that the interfaces don't come from super class
453 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
454 InstanceKlass::cast(super_klass)->transitive_interfaces();
455 if (ti != sti && ti != NULL && !ti->is_shared()) {
456 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
457 }
458 }
459
460 // local interfaces can be empty
461 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
462 local_interfaces != NULL && !local_interfaces->is_shared()) {
463 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
464 }
465 }
466
467 // This function deallocates the metadata and C heap pointers that the
468 // InstanceKlass points to.
469 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
470
471 // Orphan the mirror first, CMS thinks it's still live.
472 if (java_mirror() != NULL) {
473 java_lang_Class::set_klass(java_mirror(), NULL);
474 }
475
476 // Also remove mirror from handles
477 loader_data->remove_handle(_java_mirror);
478
479 // Need to take this class off the class loader data list.
480 loader_data->remove_class(this);
481
482 // The array_klass for this class is created later, after error handling.
483 // For class redefinition, we keep the original class so this scratch class
484 // doesn't have an array class. Either way, assert that there is nothing
485 // to deallocate.
486 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
487
488 // Release C heap allocated data that this might point to, which includes
489 // reference counting symbol names.
490 release_C_heap_structures();
491
492 deallocate_methods(loader_data, methods());
493 set_methods(NULL);
494
495 if (method_ordering() != NULL &&
496 method_ordering() != Universe::the_empty_int_array() &&
497 !method_ordering()->is_shared()) {
498 MetadataFactory::free_array<int>(loader_data, method_ordering());
499 }
500 set_method_ordering(NULL);
501
502 // default methods can be empty
503 if (default_methods() != NULL &&
504 default_methods() != Universe::the_empty_method_array() &&
505 !default_methods()->is_shared()) {
506 MetadataFactory::free_array<Method*>(loader_data, default_methods());
507 }
508 // Do NOT deallocate the default methods, they are owned by superinterfaces.
509 set_default_methods(NULL);
510
511 // default methods vtable indices can be empty
512 if (default_vtable_indices() != NULL &&
513 !default_vtable_indices()->is_shared()) {
514 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
515 }
516 set_default_vtable_indices(NULL);
517
518
519 // This array is in Klass, but remove it with the InstanceKlass since
520 // this place would be the only caller and it can share memory with transitive
521 // interfaces.
522 if (secondary_supers() != NULL &&
523 secondary_supers() != Universe::the_empty_klass_array() &&
524 // see comments in compute_secondary_supers about the following cast
525 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
526 !secondary_supers()->is_shared()) {
527 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
528 }
529 set_secondary_supers(NULL);
530
531 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
532 set_transitive_interfaces(NULL);
533 set_local_interfaces(NULL);
534
535 if (fields() != NULL && !fields()->is_shared()) {
536 MetadataFactory::free_array<jushort>(loader_data, fields());
537 }
538 set_fields(NULL, 0);
539
540 // If a method from a redefined class is using this constant pool, don't
541 // delete it, yet. The new class's previous version will point to this.
542 if (constants() != NULL) {
543 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
544 if (!constants()->is_shared()) {
545 MetadataFactory::free_metadata(loader_data, constants());
546 }
547 // Delete any cached resolution errors for the constant pool
548 SystemDictionary::delete_resolution_error(constants());
549
550 set_constants(NULL);
551 }
552
553 if (inner_classes() != NULL &&
554 inner_classes() != Universe::the_empty_short_array() &&
555 !inner_classes()->is_shared()) {
556 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
557 }
558 set_inner_classes(NULL);
559
560 if (nest_members() != NULL &&
561 nest_members() != Universe::the_empty_short_array() &&
562 !nest_members()->is_shared()) {
563 MetadataFactory::free_array<jushort>(loader_data, nest_members());
564 }
565 set_nest_members(NULL);
566
567 // We should deallocate the Annotations instance if it's not in shared spaces.
568 if (annotations() != NULL && !annotations()->is_shared()) {
569 MetadataFactory::free_metadata(loader_data, annotations());
570 }
571 set_annotations(NULL);
572 }
573
574 bool InstanceKlass::should_be_initialized() const {
575 return !is_initialized();
576 }
577
578 klassItable InstanceKlass::itable() const {
579 return klassItable(const_cast<InstanceKlass*>(this));
580 }
581
582 void InstanceKlass::eager_initialize(Thread *thread) {
583 if (!EagerInitialization) return;
584
585 if (this->is_not_initialized()) {
586 // abort if the the class has a class initializer
587 if (this->class_initializer() != NULL) return;
588
589 // abort if it is java.lang.Object (initialization is handled in genesis)
590 Klass* super_klass = super();
591 if (super_klass == NULL) return;
592
593 // abort if the super class should be initialized
594 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
595
596 // call body to expose the this pointer
597 eager_initialize_impl();
598 }
599 }
600
601 // JVMTI spec thinks there are signers and protection domain in the
602 // instanceKlass. These accessors pretend these fields are there.
603 // The hprof specification also thinks these fields are in InstanceKlass.
604 oop InstanceKlass::protection_domain() const {
605 // return the protection_domain from the mirror
606 return java_lang_Class::protection_domain(java_mirror());
607 }
608
609 // To remove these from requires an incompatible change and CCC request.
610 objArrayOop InstanceKlass::signers() const {
611 // return the signers from the mirror
612 return java_lang_Class::signers(java_mirror());
613 }
614
615 oop InstanceKlass::init_lock() const {
616 // return the init lock from the mirror
617 oop lock = java_lang_Class::init_lock(java_mirror());
618 // Prevent reordering with any access of initialization state
619 OrderAccess::loadload();
620 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
621 "only fully initialized state can have a null lock");
622 return lock;
623 }
624
625 // Set the initialization lock to null so the object can be GC'ed. Any racing
626 // threads to get this lock will see a null lock and will not lock.
627 // That's okay because they all check for initialized state after getting
628 // the lock and return.
629 void InstanceKlass::fence_and_clear_init_lock() {
630 // make sure previous stores are all done, notably the init_state.
631 OrderAccess::storestore();
632 java_lang_Class::set_init_lock(java_mirror(), NULL);
633 assert(!is_not_initialized(), "class must be initialized now");
634 }
635
636 void InstanceKlass::eager_initialize_impl() {
637 EXCEPTION_MARK;
638 HandleMark hm(THREAD);
639 Handle h_init_lock(THREAD, init_lock());
640 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
641
642 // abort if someone beat us to the initialization
643 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
644
645 ClassState old_state = init_state();
646 link_class_impl(true, THREAD);
647 if (HAS_PENDING_EXCEPTION) {
648 CLEAR_PENDING_EXCEPTION;
649 // Abort if linking the class throws an exception.
650
651 // Use a test to avoid redundantly resetting the state if there's
652 // no change. Set_init_state() asserts that state changes make
653 // progress, whereas here we might just be spinning in place.
654 if (old_state != _init_state)
655 set_init_state(old_state);
656 } else {
657 // linking successfull, mark class as initialized
658 set_init_state(fully_initialized);
659 fence_and_clear_init_lock();
660 // trace
661 if (log_is_enabled(Info, class, init)) {
662 ResourceMark rm(THREAD);
663 log_info(class, init)("[Initialized %s without side effects]", external_name());
664 }
665 }
666 }
667
668
669 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
670 // process. The step comments refers to the procedure described in that section.
671 // Note: implementation moved to static method to expose the this pointer.
672 void InstanceKlass::initialize(TRAPS) {
673 if (this->should_be_initialized()) {
674 initialize_impl(CHECK);
675 // Note: at this point the class may be initialized
676 // OR it may be in the state of being initialized
677 // in case of recursive initialization!
678 } else {
679 assert(is_initialized(), "sanity check");
680 }
681 }
682
683
684 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
685 // 1) Verify the bytecodes
686 Verifier::Mode mode =
687 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
688 return Verifier::verify(this, mode, should_verify_class(), THREAD);
689 }
690
691
692 // Used exclusively by the shared spaces dump mechanism to prevent
693 // classes mapped into the shared regions in new VMs from appearing linked.
694
695 void InstanceKlass::unlink_class() {
696 assert(is_linked(), "must be linked");
697 _init_state = loaded;
698 }
699
700 void InstanceKlass::link_class(TRAPS) {
701 assert(is_loaded(), "must be loaded");
702 if (!is_linked()) {
703 link_class_impl(true, CHECK);
704 }
705 }
706
707 // Called to verify that a class can link during initialization, without
708 // throwing a VerifyError.
709 bool InstanceKlass::link_class_or_fail(TRAPS) {
710 assert(is_loaded(), "must be loaded");
711 if (!is_linked()) {
712 link_class_impl(false, CHECK_false);
713 }
714 return is_linked();
715 }
716
717 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
718 if (DumpSharedSpaces && is_in_error_state()) {
719 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
720 // the class has failed verification. Throwing the NoClassDefFoundError here is just
721 // a convenient way to stop repeat attempts to verify the same (bad) class.
722 //
723 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
724 // if we are executing Java code. This is not a problem for CDS dumping phase since
725 // it doesn't execute any Java code.
726 ResourceMark rm(THREAD);
727 Exceptions::fthrow(THREAD_AND_LOCATION,
728 vmSymbols::java_lang_NoClassDefFoundError(),
729 "Class %s, or one of its supertypes, failed class initialization",
730 external_name());
731 return false;
732 }
733 // return if already verified
734 if (is_linked()) {
735 return true;
736 }
737
738 // Timing
739 // timer handles recursion
740 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
741 JavaThread* jt = (JavaThread*)THREAD;
742
743 // link super class before linking this class
744 Klass* super_klass = super();
745 if (super_klass != NULL) {
746 if (super_klass->is_interface()) { // check if super class is an interface
747 ResourceMark rm(THREAD);
748 Exceptions::fthrow(
749 THREAD_AND_LOCATION,
750 vmSymbols::java_lang_IncompatibleClassChangeError(),
751 "class %s has interface %s as super class",
752 external_name(),
753 super_klass->external_name()
754 );
755 return false;
756 }
757
758 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
759 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
760 }
761
762 // link all interfaces implemented by this class before linking this class
763 Array<InstanceKlass*>* interfaces = local_interfaces();
764 int num_interfaces = interfaces->length();
765 for (int index = 0; index < num_interfaces; index++) {
766 InstanceKlass* interk = interfaces->at(index);
767 interk->link_class_impl(throw_verifyerror, CHECK_false);
768 }
769
770 // in case the class is linked in the process of linking its superclasses
771 if (is_linked()) {
772 return true;
773 }
774
775 // trace only the link time for this klass that includes
776 // the verification time
777 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
778 ClassLoader::perf_class_link_selftime(),
779 ClassLoader::perf_classes_linked(),
780 jt->get_thread_stat()->perf_recursion_counts_addr(),
781 jt->get_thread_stat()->perf_timers_addr(),
782 PerfClassTraceTime::CLASS_LINK);
783
784 // verification & rewriting
785 {
786 HandleMark hm(THREAD);
787 Handle h_init_lock(THREAD, init_lock());
788 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
789 // rewritten will have been set if loader constraint error found
790 // on an earlier link attempt
791 // don't verify or rewrite if already rewritten
792 //
793
794 if (!is_linked()) {
795 if (!is_rewritten()) {
796 {
797 bool verify_ok = verify_code(throw_verifyerror, THREAD);
798 if (!verify_ok) {
799 return false;
800 }
801 }
802
803 // Just in case a side-effect of verify linked this class already
804 // (which can sometimes happen since the verifier loads classes
805 // using custom class loaders, which are free to initialize things)
806 if (is_linked()) {
807 return true;
808 }
809
810 // also sets rewritten
811 rewrite_class(CHECK_false);
812 } else if (is_shared()) {
813 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
814 }
815
816 // relocate jsrs and link methods after they are all rewritten
817 link_methods(CHECK_false);
818
819 // Initialize the vtable and interface table after
820 // methods have been rewritten since rewrite may
821 // fabricate new Method*s.
822 // also does loader constraint checking
823 //
824 // initialize_vtable and initialize_itable need to be rerun for
825 // a shared class if the class is not loaded by the NULL classloader.
826 ClassLoaderData * loader_data = class_loader_data();
827 if (!(is_shared() &&
828 loader_data->is_the_null_class_loader_data())) {
829 vtable().initialize_vtable(true, CHECK_false);
830 itable().initialize_itable(true, CHECK_false);
831 }
832 #ifdef ASSERT
833 else {
834 vtable().verify(tty, true);
835 // In case itable verification is ever added.
836 // itable().verify(tty, true);
837 }
838 #endif
839 set_init_state(linked);
840 if (JvmtiExport::should_post_class_prepare()) {
841 Thread *thread = THREAD;
842 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
843 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
844 }
845 }
846 }
847 return true;
848 }
849
850 // Rewrite the byte codes of all of the methods of a class.
851 // The rewriter must be called exactly once. Rewriting must happen after
852 // verification but before the first method of the class is executed.
853 void InstanceKlass::rewrite_class(TRAPS) {
854 assert(is_loaded(), "must be loaded");
855 if (is_rewritten()) {
856 assert(is_shared(), "rewriting an unshared class?");
857 return;
858 }
859 Rewriter::rewrite(this, CHECK);
860 set_rewritten();
861 }
862
863 // Now relocate and link method entry points after class is rewritten.
864 // This is outside is_rewritten flag. In case of an exception, it can be
865 // executed more than once.
866 void InstanceKlass::link_methods(TRAPS) {
867 int len = methods()->length();
868 for (int i = len-1; i >= 0; i--) {
869 methodHandle m(THREAD, methods()->at(i));
870
871 // Set up method entry points for compiler and interpreter .
872 m->link_method(m, CHECK);
873 }
874 }
875
876 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
877 void InstanceKlass::initialize_super_interfaces(TRAPS) {
878 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
879 for (int i = 0; i < local_interfaces()->length(); ++i) {
880 InstanceKlass* ik = local_interfaces()->at(i);
881
882 // Initialization is depth first search ie. we start with top of the inheritance tree
883 // has_nonstatic_concrete_methods drives searching superinterfaces since it
884 // means has_nonstatic_concrete_methods in its superinterface hierarchy
885 if (ik->has_nonstatic_concrete_methods()) {
886 ik->initialize_super_interfaces(CHECK);
887 }
888
889 // Only initialize() interfaces that "declare" concrete methods.
890 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
891 ik->initialize(CHECK);
892 }
893 }
894 }
895
896 void InstanceKlass::initialize_impl(TRAPS) {
897 HandleMark hm(THREAD);
898
899 // Make sure klass is linked (verified) before initialization
900 // A class could already be verified, since it has been reflected upon.
901 link_class(CHECK);
902
903 DTRACE_CLASSINIT_PROBE(required, -1);
904
905 bool wait = false;
906
907 // refer to the JVM book page 47 for description of steps
908 // Step 1
909 {
910 Handle h_init_lock(THREAD, init_lock());
911 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
912
913 Thread *self = THREAD; // it's passed the current thread
914
915 // Step 2
916 // If we were to use wait() instead of waitInterruptibly() then
917 // we might end up throwing IE from link/symbol resolution sites
918 // that aren't expected to throw. This would wreak havoc. See 6320309.
919 while(is_being_initialized() && !is_reentrant_initialization(self)) {
920 wait = true;
921 ol.waitUninterruptibly(CHECK);
922 }
923
924 // Step 3
925 if (is_being_initialized() && is_reentrant_initialization(self)) {
926 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
927 return;
928 }
929
930 // Step 4
931 if (is_initialized()) {
932 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
933 return;
934 }
935
936 // Step 5
937 if (is_in_error_state()) {
938 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
939 ResourceMark rm(THREAD);
940 const char* desc = "Could not initialize class ";
941 const char* className = external_name();
942 size_t msglen = strlen(desc) + strlen(className) + 1;
943 char* message = NEW_RESOURCE_ARRAY(char, msglen);
944 if (NULL == message) {
945 // Out of memory: can't create detailed error message
946 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
947 } else {
948 jio_snprintf(message, msglen, "%s%s", desc, className);
949 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
950 }
951 }
952
953 // Step 6
954 set_init_state(being_initialized);
955 set_init_thread(self);
956 }
957
958 // Step 7
959 // Next, if C is a class rather than an interface, initialize it's super class and super
960 // interfaces.
961 if (!is_interface()) {
962 Klass* super_klass = super();
963 if (super_klass != NULL && super_klass->should_be_initialized()) {
964 super_klass->initialize(THREAD);
965 }
966 // If C implements any interface that declares a non-static, concrete method,
967 // the initialization of C triggers initialization of its super interfaces.
968 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
969 // having a superinterface that declares, non-static, concrete methods
970 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
971 initialize_super_interfaces(THREAD);
972 }
973
974 // If any exceptions, complete abruptly, throwing the same exception as above.
975 if (HAS_PENDING_EXCEPTION) {
976 Handle e(THREAD, PENDING_EXCEPTION);
977 CLEAR_PENDING_EXCEPTION;
978 {
979 EXCEPTION_MARK;
980 // Locks object, set state, and notify all waiting threads
981 set_initialization_state_and_notify(initialization_error, THREAD);
982 CLEAR_PENDING_EXCEPTION;
983 }
984 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
985 THROW_OOP(e());
986 }
987 }
988
989
990 // Look for aot compiled methods for this klass, including class initializer.
991 AOTLoader::load_for_klass(this, THREAD);
992
993 // Step 8
994 {
995 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
996 JavaThread* jt = (JavaThread*)THREAD;
997 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
998 // Timer includes any side effects of class initialization (resolution,
999 // etc), but not recursive entry into call_class_initializer().
1000 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1001 ClassLoader::perf_class_init_selftime(),
1002 ClassLoader::perf_classes_inited(),
1003 jt->get_thread_stat()->perf_recursion_counts_addr(),
1004 jt->get_thread_stat()->perf_timers_addr(),
1005 PerfClassTraceTime::CLASS_CLINIT);
1006 call_class_initializer(THREAD);
1007 }
1008
1009 // Step 9
1010 if (!HAS_PENDING_EXCEPTION) {
1011 set_initialization_state_and_notify(fully_initialized, CHECK);
1012 {
1013 debug_only(vtable().verify(tty, true);)
1014 }
1015 }
1016 else {
1017 // Step 10 and 11
1018 Handle e(THREAD, PENDING_EXCEPTION);
1019 CLEAR_PENDING_EXCEPTION;
1020 // JVMTI has already reported the pending exception
1021 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1022 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1023 {
1024 EXCEPTION_MARK;
1025 set_initialization_state_and_notify(initialization_error, THREAD);
1026 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1027 // JVMTI has already reported the pending exception
1028 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1029 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1030 }
1031 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1032 if (e->is_a(SystemDictionary::Error_klass())) {
1033 THROW_OOP(e());
1034 } else {
1035 JavaCallArguments args(e);
1036 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1037 vmSymbols::throwable_void_signature(),
1038 &args);
1039 }
1040 }
1041 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1042 }
1043
1044
1045 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1046 Handle h_init_lock(THREAD, init_lock());
1047 if (h_init_lock() != NULL) {
1048 ObjectLocker ol(h_init_lock, THREAD);
1049 set_init_state(state);
1050 fence_and_clear_init_lock();
1051 ol.notify_all(CHECK);
1052 } else {
1053 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1054 set_init_state(state);
1055 }
1056 }
1057
1058 Klass* InstanceKlass::implementor() const {
1059 assert_locked_or_safepoint(Compile_lock);
1060 Klass** k = adr_implementor();
1061 if (k == NULL) {
1062 return NULL;
1063 } else {
1064 return *k;
1065 }
1066 }
1067
1068 void InstanceKlass::set_implementor(Klass* k) {
1069 assert_lock_strong(Compile_lock);
1070 assert(is_interface(), "not interface");
1071 Klass** addr = adr_implementor();
1072 assert(addr != NULL, "null addr");
1073 if (addr != NULL) {
1074 *addr = k;
1075 }
1076 }
1077
1078 int InstanceKlass::nof_implementors() const {
1079 assert_lock_strong(Compile_lock);
1080 Klass* k = implementor();
1081 if (k == NULL) {
1082 return 0;
1083 } else if (k != this) {
1084 return 1;
1085 } else {
1086 return 2;
1087 }
1088 }
1089
1090 // The embedded _implementor field can only record one implementor.
1091 // When there are more than one implementors, the _implementor field
1092 // is set to the interface Klass* itself. Following are the possible
1093 // values for the _implementor field:
1094 // NULL - no implementor
1095 // implementor Klass* - one implementor
1096 // self - more than one implementor
1097 //
1098 // The _implementor field only exists for interfaces.
1099 void InstanceKlass::add_implementor(Klass* k) {
1100 assert_lock_strong(Compile_lock);
1101 assert(is_interface(), "not interface");
1102 // Filter out my subinterfaces.
1103 // (Note: Interfaces are never on the subklass list.)
1104 if (InstanceKlass::cast(k)->is_interface()) return;
1105
1106 // Filter out subclasses whose supers already implement me.
1107 // (Note: CHA must walk subclasses of direct implementors
1108 // in order to locate indirect implementors.)
1109 Klass* sk = k->super();
1110 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1111 // We only need to check one immediate superclass, since the
1112 // implements_interface query looks at transitive_interfaces.
1113 // Any supers of the super have the same (or fewer) transitive_interfaces.
1114 return;
1115
1116 Klass* ik = implementor();
1117 if (ik == NULL) {
1118 set_implementor(k);
1119 } else if (ik != this) {
1120 // There is already an implementor. Use itself as an indicator of
1121 // more than one implementors.
1122 set_implementor(this);
1123 }
1124
1125 // The implementor also implements the transitive_interfaces
1126 for (int index = 0; index < local_interfaces()->length(); index++) {
1127 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1128 }
1129 }
1130
1131 void InstanceKlass::init_implementor() {
1132 if (is_interface()) {
1133 set_implementor(NULL);
1134 }
1135 }
1136
1137
1138 void InstanceKlass::process_interfaces(Thread *thread) {
1139 // link this class into the implementors list of every interface it implements
1140 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1141 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1142 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1143 assert(interf->is_interface(), "expected interface");
1144 interf->add_implementor(this);
1145 }
1146 }
1147
1148 bool InstanceKlass::can_be_primary_super_slow() const {
1149 if (is_interface())
1150 return false;
1151 else
1152 return Klass::can_be_primary_super_slow();
1153 }
1154
1155 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1156 Array<InstanceKlass*>* transitive_interfaces) {
1157 // The secondaries are the implemented interfaces.
1158 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1159 int num_secondaries = num_extra_slots + interfaces->length();
1160 if (num_secondaries == 0) {
1161 // Must share this for correct bootstrapping!
1162 set_secondary_supers(Universe::the_empty_klass_array());
1163 return NULL;
1164 } else if (num_extra_slots == 0) {
1165 // The secondary super list is exactly the same as the transitive interfaces, so
1166 // let's use it instead of making a copy.
1167 // Redefine classes has to be careful not to delete this!
1168 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1169 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1170 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1171 return NULL;
1172 } else {
1173 // Copy transitive interfaces to a temporary growable array to be constructed
1174 // into the secondary super list with extra slots.
1175 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1176 for (int i = 0; i < interfaces->length(); i++) {
1177 secondaries->push(interfaces->at(i));
1178 }
1179 return secondaries;
1180 }
1181 }
1182
1183 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1184 if (k->is_interface()) {
1185 return implements_interface(k);
1186 } else {
1187 return Klass::compute_is_subtype_of(k);
1188 }
1189 }
1190
1191 bool InstanceKlass::implements_interface(Klass* k) const {
1192 if (this == k) return true;
1193 assert(k->is_interface(), "should be an interface class");
1194 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1195 if (transitive_interfaces()->at(i) == k) {
1196 return true;
1197 }
1198 }
1199 return false;
1200 }
1201
1202 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1203 // Verify direct super interface
1204 if (this == k) return true;
1205 assert(k->is_interface(), "should be an interface class");
1206 for (int i = 0; i < local_interfaces()->length(); i++) {
1207 if (local_interfaces()->at(i) == k) {
1208 return true;
1209 }
1210 }
1211 return false;
1212 }
1213
1214 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1215 if (length < 0) {
1216 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length));
1217 }
1218 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1219 report_java_out_of_memory("Requested array size exceeds VM limit");
1220 JvmtiExport::post_array_size_exhausted();
1221 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1222 }
1223 int size = objArrayOopDesc::object_size(length);
1224 Klass* ak = array_klass(n, CHECK_NULL);
1225 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1226 /* do_zero */ true, CHECK_NULL);
1227 return o;
1228 }
1229
1230 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1231 if (TraceFinalizerRegistration) {
1232 tty->print("Registered ");
1233 i->print_value_on(tty);
1234 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1235 }
1236 instanceHandle h_i(THREAD, i);
1237 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1238 JavaValue result(T_VOID);
1239 JavaCallArguments args(h_i);
1240 methodHandle mh (THREAD, Universe::finalizer_register_method());
1241 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1242 return h_i();
1243 }
1244
1245 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1246 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1247 int size = size_helper(); // Query before forming handle.
1248
1249 instanceOop i;
1250
1251 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1252 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1253 i = register_finalizer(i, CHECK_NULL);
1254 }
1255 return i;
1256 }
1257
1258 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1259 return instanceHandle(THREAD, allocate_instance(THREAD));
1260 }
1261
1262 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1263 if (is_interface() || is_abstract()) {
1264 ResourceMark rm(THREAD);
1265 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1266 : vmSymbols::java_lang_InstantiationException(), external_name());
1267 }
1268 if (this == SystemDictionary::Class_klass()) {
1269 ResourceMark rm(THREAD);
1270 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1271 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1272 }
1273 }
1274
1275 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1276 // Need load-acquire for lock-free read
1277 if (array_klasses_acquire() == NULL) {
1278 if (or_null) return NULL;
1279
1280 ResourceMark rm;
1281 JavaThread *jt = (JavaThread *)THREAD;
1282 {
1283 // Atomic creation of array_klasses
1284 MutexLocker mc(Compile_lock, THREAD); // for vtables
1285 MutexLocker ma(MultiArray_lock, THREAD);
1286
1287 // Check if update has already taken place
1288 if (array_klasses() == NULL) {
1289 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1290 // use 'release' to pair with lock-free load
1291 release_set_array_klasses(k);
1292 }
1293 }
1294 }
1295 // _this will always be set at this point
1296 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1297 if (or_null) {
1298 return oak->array_klass_or_null(n);
1299 }
1300 return oak->array_klass(n, THREAD);
1301 }
1302
1303 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1304 return array_klass_impl(or_null, 1, THREAD);
1305 }
1306
1307 static int call_class_initializer_counter = 0; // for debugging
1308
1309 Method* InstanceKlass::class_initializer() const {
1310 Method* clinit = find_method(
1311 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1312 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1313 return clinit;
1314 }
1315 return NULL;
1316 }
1317
1318 void InstanceKlass::call_class_initializer(TRAPS) {
1319 if (ReplayCompiles &&
1320 (ReplaySuppressInitializers == 1 ||
1321 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1322 // Hide the existence of the initializer for the purpose of replaying the compile
1323 return;
1324 }
1325
1326 methodHandle h_method(THREAD, class_initializer());
1327 assert(!is_initialized(), "we cannot initialize twice");
1328 LogTarget(Info, class, init) lt;
1329 if (lt.is_enabled()) {
1330 ResourceMark rm;
1331 LogStream ls(lt);
1332 ls.print("%d Initializing ", call_class_initializer_counter++);
1333 name()->print_value_on(&ls);
1334 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1335 }
1336 if (h_method() != NULL) {
1337 JavaCallArguments args; // No arguments
1338 JavaValue result(T_VOID);
1339 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1340 }
1341 }
1342
1343
1344 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1345 InterpreterOopMap* entry_for) {
1346 // Lazily create the _oop_map_cache at first request
1347 // Lock-free access requires load_acquire.
1348 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1349 if (oop_map_cache == NULL) {
1350 MutexLocker x(OopMapCacheAlloc_lock);
1351 // Check if _oop_map_cache was allocated while we were waiting for this lock
1352 if ((oop_map_cache = _oop_map_cache) == NULL) {
1353 oop_map_cache = new OopMapCache();
1354 // Ensure _oop_map_cache is stable, since it is examined without a lock
1355 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1356 }
1357 }
1358 // _oop_map_cache is constant after init; lookup below does its own locking.
1359 oop_map_cache->lookup(method, bci, entry_for);
1360 }
1361
1362
1363 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1364 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1365 Symbol* f_name = fs.name();
1366 Symbol* f_sig = fs.signature();
1367 if (f_name == name && f_sig == sig) {
1368 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1369 return true;
1370 }
1371 }
1372 return false;
1373 }
1374
1375
1376 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1377 const int n = local_interfaces()->length();
1378 for (int i = 0; i < n; i++) {
1379 Klass* intf1 = local_interfaces()->at(i);
1380 assert(intf1->is_interface(), "just checking type");
1381 // search for field in current interface
1382 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1383 assert(fd->is_static(), "interface field must be static");
1384 return intf1;
1385 }
1386 // search for field in direct superinterfaces
1387 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1388 if (intf2 != NULL) return intf2;
1389 }
1390 // otherwise field lookup fails
1391 return NULL;
1392 }
1393
1394
1395 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1396 // search order according to newest JVM spec (5.4.3.2, p.167).
1397 // 1) search for field in current klass
1398 if (find_local_field(name, sig, fd)) {
1399 return const_cast<InstanceKlass*>(this);
1400 }
1401 // 2) search for field recursively in direct superinterfaces
1402 { Klass* intf = find_interface_field(name, sig, fd);
1403 if (intf != NULL) return intf;
1404 }
1405 // 3) apply field lookup recursively if superclass exists
1406 { Klass* supr = super();
1407 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1408 }
1409 // 4) otherwise field lookup fails
1410 return NULL;
1411 }
1412
1413
1414 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1415 // search order according to newest JVM spec (5.4.3.2, p.167).
1416 // 1) search for field in current klass
1417 if (find_local_field(name, sig, fd)) {
1418 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1419 }
1420 // 2) search for field recursively in direct superinterfaces
1421 if (is_static) {
1422 Klass* intf = find_interface_field(name, sig, fd);
1423 if (intf != NULL) return intf;
1424 }
1425 // 3) apply field lookup recursively if superclass exists
1426 { Klass* supr = super();
1427 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1428 }
1429 // 4) otherwise field lookup fails
1430 return NULL;
1431 }
1432
1433
1434 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1435 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1436 if (fs.offset() == offset) {
1437 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1438 if (fd->is_static() == is_static) return true;
1439 }
1440 }
1441 return false;
1442 }
1443
1444
1445 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1446 Klass* klass = const_cast<InstanceKlass*>(this);
1447 while (klass != NULL) {
1448 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1449 return true;
1450 }
1451 klass = klass->super();
1452 }
1453 return false;
1454 }
1455
1456
1457 void InstanceKlass::methods_do(void f(Method* method)) {
1458 // Methods aren't stable until they are loaded. This can be read outside
1459 // a lock through the ClassLoaderData for profiling
1460 if (!is_loaded()) {
1461 return;
1462 }
1463
1464 int len = methods()->length();
1465 for (int index = 0; index < len; index++) {
1466 Method* m = methods()->at(index);
1467 assert(m->is_method(), "must be method");
1468 f(m);
1469 }
1470 }
1471
1472
1473 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1474 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1475 if (fs.access_flags().is_static()) {
1476 fieldDescriptor& fd = fs.field_descriptor();
1477 cl->do_field(&fd);
1478 }
1479 }
1480 }
1481
1482
1483 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1484 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1485 if (fs.access_flags().is_static()) {
1486 fieldDescriptor& fd = fs.field_descriptor();
1487 f(&fd, mirror, CHECK);
1488 }
1489 }
1490 }
1491
1492
1493 static int compare_fields_by_offset(int* a, int* b) {
1494 return a[0] - b[0];
1495 }
1496
1497 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1498 InstanceKlass* super = superklass();
1499 if (super != NULL) {
1500 super->do_nonstatic_fields(cl);
1501 }
1502 fieldDescriptor fd;
1503 int length = java_fields_count();
1504 // In DebugInfo nonstatic fields are sorted by offset.
1505 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1506 int j = 0;
1507 for (int i = 0; i < length; i += 1) {
1508 fd.reinitialize(this, i);
1509 if (!fd.is_static()) {
1510 fields_sorted[j + 0] = fd.offset();
1511 fields_sorted[j + 1] = i;
1512 j += 2;
1513 }
1514 }
1515 if (j > 0) {
1516 length = j;
1517 // _sort_Fn is defined in growableArray.hpp.
1518 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1519 for (int i = 0; i < length; i += 2) {
1520 fd.reinitialize(this, fields_sorted[i + 1]);
1521 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1522 cl->do_field(&fd);
1523 }
1524 }
1525 FREE_C_HEAP_ARRAY(int, fields_sorted);
1526 }
1527
1528
1529 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1530 if (array_klasses() != NULL)
1531 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1532 }
1533
1534 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1535 if (array_klasses() != NULL)
1536 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1537 }
1538
1539 #ifdef ASSERT
1540 static int linear_search(const Array<Method*>* methods,
1541 const Symbol* name,
1542 const Symbol* signature) {
1543 const int len = methods->length();
1544 for (int index = 0; index < len; index++) {
1545 const Method* const m = methods->at(index);
1546 assert(m->is_method(), "must be method");
1547 if (m->signature() == signature && m->name() == name) {
1548 return index;
1549 }
1550 }
1551 return -1;
1552 }
1553 #endif
1554
1555 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1556 int len = methods->length();
1557 // methods are sorted, so do binary search
1558 int l = 0;
1559 int h = len - 1;
1560 while (l <= h) {
1561 int mid = (l + h) >> 1;
1562 Method* m = methods->at(mid);
1563 assert(m->is_method(), "must be method");
1564 int res = m->name()->fast_compare(name);
1565 if (res == 0) {
1566 return mid;
1567 } else if (res < 0) {
1568 l = mid + 1;
1569 } else {
1570 h = mid - 1;
1571 }
1572 }
1573 return -1;
1574 }
1575
1576 // find_method looks up the name/signature in the local methods array
1577 Method* InstanceKlass::find_method(const Symbol* name,
1578 const Symbol* signature) const {
1579 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1580 }
1581
1582 Method* InstanceKlass::find_method_impl(const Symbol* name,
1583 const Symbol* signature,
1584 OverpassLookupMode overpass_mode,
1585 StaticLookupMode static_mode,
1586 PrivateLookupMode private_mode) const {
1587 return InstanceKlass::find_method_impl(methods(),
1588 name,
1589 signature,
1590 overpass_mode,
1591 static_mode,
1592 private_mode);
1593 }
1594
1595 // find_instance_method looks up the name/signature in the local methods array
1596 // and skips over static methods
1597 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1598 const Symbol* name,
1599 const Symbol* signature,
1600 PrivateLookupMode private_mode) {
1601 Method* const meth = InstanceKlass::find_method_impl(methods,
1602 name,
1603 signature,
1604 find_overpass,
1605 skip_static,
1606 private_mode);
1607 assert(((meth == NULL) || !meth->is_static()),
1608 "find_instance_method should have skipped statics");
1609 return meth;
1610 }
1611
1612 // find_instance_method looks up the name/signature in the local methods array
1613 // and skips over static methods
1614 Method* InstanceKlass::find_instance_method(const Symbol* name,
1615 const Symbol* signature,
1616 PrivateLookupMode private_mode) const {
1617 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1618 }
1619
1620 // Find looks up the name/signature in the local methods array
1621 // and filters on the overpass, static and private flags
1622 // This returns the first one found
1623 // note that the local methods array can have up to one overpass, one static
1624 // and one instance (private or not) with the same name/signature
1625 Method* InstanceKlass::find_local_method(const Symbol* name,
1626 const Symbol* signature,
1627 OverpassLookupMode overpass_mode,
1628 StaticLookupMode static_mode,
1629 PrivateLookupMode private_mode) const {
1630 return InstanceKlass::find_method_impl(methods(),
1631 name,
1632 signature,
1633 overpass_mode,
1634 static_mode,
1635 private_mode);
1636 }
1637
1638 // Find looks up the name/signature in the local methods array
1639 // and filters on the overpass, static and private flags
1640 // This returns the first one found
1641 // note that the local methods array can have up to one overpass, one static
1642 // and one instance (private or not) with the same name/signature
1643 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1644 const Symbol* name,
1645 const Symbol* signature,
1646 OverpassLookupMode overpass_mode,
1647 StaticLookupMode static_mode,
1648 PrivateLookupMode private_mode) {
1649 return InstanceKlass::find_method_impl(methods,
1650 name,
1651 signature,
1652 overpass_mode,
1653 static_mode,
1654 private_mode);
1655 }
1656
1657 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1658 const Symbol* name,
1659 const Symbol* signature) {
1660 return InstanceKlass::find_method_impl(methods,
1661 name,
1662 signature,
1663 find_overpass,
1664 find_static,
1665 find_private);
1666 }
1667
1668 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1669 const Symbol* name,
1670 const Symbol* signature,
1671 OverpassLookupMode overpass_mode,
1672 StaticLookupMode static_mode,
1673 PrivateLookupMode private_mode) {
1674 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1675 return hit >= 0 ? methods->at(hit): NULL;
1676 }
1677
1678 // true if method matches signature and conforms to skipping_X conditions.
1679 static bool method_matches(const Method* m,
1680 const Symbol* signature,
1681 bool skipping_overpass,
1682 bool skipping_static,
1683 bool skipping_private) {
1684 return ((m->signature() == signature) &&
1685 (!skipping_overpass || !m->is_overpass()) &&
1686 (!skipping_static || !m->is_static()) &&
1687 (!skipping_private || !m->is_private()));
1688 }
1689
1690 // Used directly for default_methods to find the index into the
1691 // default_vtable_indices, and indirectly by find_method
1692 // find_method_index looks in the local methods array to return the index
1693 // of the matching name/signature. If, overpass methods are being ignored,
1694 // the search continues to find a potential non-overpass match. This capability
1695 // is important during method resolution to prefer a static method, for example,
1696 // over an overpass method.
1697 // There is the possibility in any _method's array to have the same name/signature
1698 // for a static method, an overpass method and a local instance method
1699 // To correctly catch a given method, the search criteria may need
1700 // to explicitly skip the other two. For local instance methods, it
1701 // is often necessary to skip private methods
1702 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1703 const Symbol* name,
1704 const Symbol* signature,
1705 OverpassLookupMode overpass_mode,
1706 StaticLookupMode static_mode,
1707 PrivateLookupMode private_mode) {
1708 const bool skipping_overpass = (overpass_mode == skip_overpass);
1709 const bool skipping_static = (static_mode == skip_static);
1710 const bool skipping_private = (private_mode == skip_private);
1711 const int hit = binary_search(methods, name);
1712 if (hit != -1) {
1713 const Method* const m = methods->at(hit);
1714
1715 // Do linear search to find matching signature. First, quick check
1716 // for common case, ignoring overpasses if requested.
1717 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1718 return hit;
1719 }
1720
1721 // search downwards through overloaded methods
1722 int i;
1723 for (i = hit - 1; i >= 0; --i) {
1724 const Method* const m = methods->at(i);
1725 assert(m->is_method(), "must be method");
1726 if (m->name() != name) {
1727 break;
1728 }
1729 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1730 return i;
1731 }
1732 }
1733 // search upwards
1734 for (i = hit + 1; i < methods->length(); ++i) {
1735 const Method* const m = methods->at(i);
1736 assert(m->is_method(), "must be method");
1737 if (m->name() != name) {
1738 break;
1739 }
1740 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1741 return i;
1742 }
1743 }
1744 // not found
1745 #ifdef ASSERT
1746 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1747 linear_search(methods, name, signature);
1748 assert(-1 == index, "binary search should have found entry %d", index);
1749 #endif
1750 }
1751 return -1;
1752 }
1753
1754 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1755 return find_method_by_name(methods(), name, end);
1756 }
1757
1758 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1759 const Symbol* name,
1760 int* end_ptr) {
1761 assert(end_ptr != NULL, "just checking");
1762 int start = binary_search(methods, name);
1763 int end = start + 1;
1764 if (start != -1) {
1765 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1766 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1767 *end_ptr = end;
1768 return start;
1769 }
1770 return -1;
1771 }
1772
1773 // uncached_lookup_method searches both the local class methods array and all
1774 // superclasses methods arrays, skipping any overpass methods in superclasses,
1775 // and possibly skipping private methods.
1776 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1777 const Symbol* signature,
1778 OverpassLookupMode overpass_mode,
1779 PrivateLookupMode private_mode) const {
1780 OverpassLookupMode overpass_local_mode = overpass_mode;
1781 const Klass* klass = this;
1782 while (klass != NULL) {
1783 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1784 signature,
1785 overpass_local_mode,
1786 find_static,
1787 private_mode);
1788 if (method != NULL) {
1789 return method;
1790 }
1791 klass = klass->super();
1792 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1793 }
1794 return NULL;
1795 }
1796
1797 #ifdef ASSERT
1798 // search through class hierarchy and return true if this class or
1799 // one of the superclasses was redefined
1800 bool InstanceKlass::has_redefined_this_or_super() const {
1801 const Klass* klass = this;
1802 while (klass != NULL) {
1803 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1804 return true;
1805 }
1806 klass = klass->super();
1807 }
1808 return false;
1809 }
1810 #endif
1811
1812 // lookup a method in the default methods list then in all transitive interfaces
1813 // Do NOT return private or static methods
1814 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1815 Symbol* signature) const {
1816 Method* m = NULL;
1817 if (default_methods() != NULL) {
1818 m = find_method(default_methods(), name, signature);
1819 }
1820 // Look up interfaces
1821 if (m == NULL) {
1822 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1823 }
1824 return m;
1825 }
1826
1827 // lookup a method in all the interfaces that this class implements
1828 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1829 // They should only be found in the initial InterfaceMethodRef
1830 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1831 Symbol* signature,
1832 DefaultsLookupMode defaults_mode) const {
1833 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1834 int num_ifs = all_ifs->length();
1835 InstanceKlass *ik = NULL;
1836 for (int i = 0; i < num_ifs; i++) {
1837 ik = all_ifs->at(i);
1838 Method* m = ik->lookup_method(name, signature);
1839 if (m != NULL && m->is_public() && !m->is_static() &&
1840 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1841 return m;
1842 }
1843 }
1844 return NULL;
1845 }
1846
1847 /* jni_id_for_impl for jfieldIds only */
1848 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1849 MutexLocker ml(JfieldIdCreation_lock);
1850 // Retry lookup after we got the lock
1851 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1852 if (probe == NULL) {
1853 // Slow case, allocate new static field identifier
1854 probe = new JNIid(this, offset, jni_ids());
1855 set_jni_ids(probe);
1856 }
1857 return probe;
1858 }
1859
1860
1861 /* jni_id_for for jfieldIds only */
1862 JNIid* InstanceKlass::jni_id_for(int offset) {
1863 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1864 if (probe == NULL) {
1865 probe = jni_id_for_impl(offset);
1866 }
1867 return probe;
1868 }
1869
1870 u2 InstanceKlass::enclosing_method_data(int offset) const {
1871 const Array<jushort>* const inner_class_list = inner_classes();
1872 if (inner_class_list == NULL) {
1873 return 0;
1874 }
1875 const int length = inner_class_list->length();
1876 if (length % inner_class_next_offset == 0) {
1877 return 0;
1878 }
1879 const int index = length - enclosing_method_attribute_size;
1880 assert(offset < enclosing_method_attribute_size, "invalid offset");
1881 return inner_class_list->at(index + offset);
1882 }
1883
1884 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1885 u2 method_index) {
1886 Array<jushort>* inner_class_list = inner_classes();
1887 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1888 int length = inner_class_list->length();
1889 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1890 int index = length - enclosing_method_attribute_size;
1891 inner_class_list->at_put(
1892 index + enclosing_method_class_index_offset, class_index);
1893 inner_class_list->at_put(
1894 index + enclosing_method_method_index_offset, method_index);
1895 }
1896 }
1897
1898 // Lookup or create a jmethodID.
1899 // This code is called by the VMThread and JavaThreads so the
1900 // locking has to be done very carefully to avoid deadlocks
1901 // and/or other cache consistency problems.
1902 //
1903 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1904 size_t idnum = (size_t)method_h->method_idnum();
1905 jmethodID* jmeths = methods_jmethod_ids_acquire();
1906 size_t length = 0;
1907 jmethodID id = NULL;
1908
1909 // We use a double-check locking idiom here because this cache is
1910 // performance sensitive. In the normal system, this cache only
1911 // transitions from NULL to non-NULL which is safe because we use
1912 // release_set_methods_jmethod_ids() to advertise the new cache.
1913 // A partially constructed cache should never be seen by a racing
1914 // thread. We also use release_store() to save a new jmethodID
1915 // in the cache so a partially constructed jmethodID should never be
1916 // seen either. Cache reads of existing jmethodIDs proceed without a
1917 // lock, but cache writes of a new jmethodID requires uniqueness and
1918 // creation of the cache itself requires no leaks so a lock is
1919 // generally acquired in those two cases.
1920 //
1921 // If the RedefineClasses() API has been used, then this cache can
1922 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1923 // Cache creation requires no leaks and we require safety between all
1924 // cache accesses and freeing of the old cache so a lock is generally
1925 // acquired when the RedefineClasses() API has been used.
1926
1927 if (jmeths != NULL) {
1928 // the cache already exists
1929 if (!idnum_can_increment()) {
1930 // the cache can't grow so we can just get the current values
1931 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1932 } else {
1933 // cache can grow so we have to be more careful
1934 if (Threads::number_of_threads() == 0 ||
1935 SafepointSynchronize::is_at_safepoint()) {
1936 // we're single threaded or at a safepoint - no locking needed
1937 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1938 } else {
1939 MutexLocker ml(JmethodIdCreation_lock);
1940 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1941 }
1942 }
1943 }
1944 // implied else:
1945 // we need to allocate a cache so default length and id values are good
1946
1947 if (jmeths == NULL || // no cache yet
1948 length <= idnum || // cache is too short
1949 id == NULL) { // cache doesn't contain entry
1950
1951 // This function can be called by the VMThread so we have to do all
1952 // things that might block on a safepoint before grabbing the lock.
1953 // Otherwise, we can deadlock with the VMThread or have a cache
1954 // consistency issue. These vars keep track of what we might have
1955 // to free after the lock is dropped.
1956 jmethodID to_dealloc_id = NULL;
1957 jmethodID* to_dealloc_jmeths = NULL;
1958
1959 // may not allocate new_jmeths or use it if we allocate it
1960 jmethodID* new_jmeths = NULL;
1961 if (length <= idnum) {
1962 // allocate a new cache that might be used
1963 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1964 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1965 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1966 // cache size is stored in element[0], other elements offset by one
1967 new_jmeths[0] = (jmethodID)size;
1968 }
1969
1970 // allocate a new jmethodID that might be used
1971 jmethodID new_id = NULL;
1972 if (method_h->is_old() && !method_h->is_obsolete()) {
1973 // The method passed in is old (but not obsolete), we need to use the current version
1974 Method* current_method = method_with_idnum((int)idnum);
1975 assert(current_method != NULL, "old and but not obsolete, so should exist");
1976 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1977 } else {
1978 // It is the current version of the method or an obsolete method,
1979 // use the version passed in
1980 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1981 }
1982
1983 if (Threads::number_of_threads() == 0 ||
1984 SafepointSynchronize::is_at_safepoint()) {
1985 // we're single threaded or at a safepoint - no locking needed
1986 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1987 &to_dealloc_id, &to_dealloc_jmeths);
1988 } else {
1989 MutexLocker ml(JmethodIdCreation_lock);
1990 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1991 &to_dealloc_id, &to_dealloc_jmeths);
1992 }
1993
1994 // The lock has been dropped so we can free resources.
1995 // Free up either the old cache or the new cache if we allocated one.
1996 if (to_dealloc_jmeths != NULL) {
1997 FreeHeap(to_dealloc_jmeths);
1998 }
1999 // free up the new ID since it wasn't needed
2000 if (to_dealloc_id != NULL) {
2001 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2002 }
2003 }
2004 return id;
2005 }
2006
2007 // Figure out how many jmethodIDs haven't been allocated, and make
2008 // sure space for them is pre-allocated. This makes getting all
2009 // method ids much, much faster with classes with more than 8
2010 // methods, and has a *substantial* effect on performance with jvmti
2011 // code that loads all jmethodIDs for all classes.
2012 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2013 int new_jmeths = 0;
2014 int length = methods()->length();
2015 for (int index = start_offset; index < length; index++) {
2016 Method* m = methods()->at(index);
2017 jmethodID id = m->find_jmethod_id_or_null();
2018 if (id == NULL) {
2019 new_jmeths++;
2020 }
2021 }
2022 if (new_jmeths != 0) {
2023 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2024 }
2025 }
2026
2027 // Common code to fetch the jmethodID from the cache or update the
2028 // cache with the new jmethodID. This function should never do anything
2029 // that causes the caller to go to a safepoint or we can deadlock with
2030 // the VMThread or have cache consistency issues.
2031 //
2032 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2033 size_t idnum, jmethodID new_id,
2034 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2035 jmethodID** to_dealloc_jmeths_p) {
2036 assert(new_id != NULL, "sanity check");
2037 assert(to_dealloc_id_p != NULL, "sanity check");
2038 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2039 assert(Threads::number_of_threads() == 0 ||
2040 SafepointSynchronize::is_at_safepoint() ||
2041 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2042
2043 // reacquire the cache - we are locked, single threaded or at a safepoint
2044 jmethodID* jmeths = methods_jmethod_ids_acquire();
2045 jmethodID id = NULL;
2046 size_t length = 0;
2047
2048 if (jmeths == NULL || // no cache yet
2049 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2050 if (jmeths != NULL) {
2051 // copy any existing entries from the old cache
2052 for (size_t index = 0; index < length; index++) {
2053 new_jmeths[index+1] = jmeths[index+1];
2054 }
2055 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2056 }
2057 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2058 } else {
2059 // fetch jmethodID (if any) from the existing cache
2060 id = jmeths[idnum+1];
2061 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2062 }
2063 if (id == NULL) {
2064 // No matching jmethodID in the existing cache or we have a new
2065 // cache or we just grew the cache. This cache write is done here
2066 // by the first thread to win the foot race because a jmethodID
2067 // needs to be unique once it is generally available.
2068 id = new_id;
2069
2070 // The jmethodID cache can be read while unlocked so we have to
2071 // make sure the new jmethodID is complete before installing it
2072 // in the cache.
2073 OrderAccess::release_store(&jmeths[idnum+1], id);
2074 } else {
2075 *to_dealloc_id_p = new_id; // save new id for later delete
2076 }
2077 return id;
2078 }
2079
2080
2081 // Common code to get the jmethodID cache length and the jmethodID
2082 // value at index idnum if there is one.
2083 //
2084 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2085 size_t idnum, size_t *length_p, jmethodID* id_p) {
2086 assert(cache != NULL, "sanity check");
2087 assert(length_p != NULL, "sanity check");
2088 assert(id_p != NULL, "sanity check");
2089
2090 // cache size is stored in element[0], other elements offset by one
2091 *length_p = (size_t)cache[0];
2092 if (*length_p <= idnum) { // cache is too short
2093 *id_p = NULL;
2094 } else {
2095 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2096 }
2097 }
2098
2099
2100 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2101 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2102 size_t idnum = (size_t)method->method_idnum();
2103 jmethodID* jmeths = methods_jmethod_ids_acquire();
2104 size_t length; // length assigned as debugging crumb
2105 jmethodID id = NULL;
2106 if (jmeths != NULL && // If there is a cache
2107 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2108 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2109 }
2110 return id;
2111 }
2112
2113 inline DependencyContext InstanceKlass::dependencies() {
2114 DependencyContext dep_context(&_dep_context);
2115 return dep_context;
2116 }
2117
2118 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2119 return dependencies().mark_dependent_nmethods(changes);
2120 }
2121
2122 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2123 dependencies().add_dependent_nmethod(nm);
2124 }
2125
2126 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2127 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2128 }
2129
2130 #ifndef PRODUCT
2131 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2132 dependencies().print_dependent_nmethods(verbose);
2133 }
2134
2135 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2136 return dependencies().is_dependent_nmethod(nm);
2137 }
2138 #endif //PRODUCT
2139
2140 void InstanceKlass::clean_weak_instanceklass_links() {
2141 clean_implementors_list();
2142 clean_method_data();
2143
2144 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2145 DependencyContext dep_context(&_dep_context);
2146 dep_context.expunge_stale_entries();
2147 }
2148
2149 void InstanceKlass::clean_implementors_list() {
2150 assert(is_loader_alive(), "this klass should be live");
2151 if (is_interface()) {
2152 if (ClassUnloading) {
2153 Klass* impl = implementor();
2154 if (impl != NULL) {
2155 if (!impl->is_loader_alive()) {
2156 // remove this guy
2157 Klass** klass = adr_implementor();
2158 assert(klass != NULL, "null klass");
2159 if (klass != NULL) {
2160 *klass = NULL;
2161 }
2162 }
2163 }
2164 }
2165 }
2166 }
2167
2168 void InstanceKlass::clean_method_data() {
2169 for (int m = 0; m < methods()->length(); m++) {
2170 MethodData* mdo = methods()->at(m)->method_data();
2171 if (mdo != NULL) {
2172 mdo->clean_method_data(/*always_clean*/false);
2173 }
2174 }
2175 }
2176
2177 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2178 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2179 ResourceMark rm;
2180 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2181 return false;
2182 }
2183
2184 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2185 if (local_interfaces != NULL) {
2186 int length = local_interfaces->length();
2187 for (int i = 0; i < length; i++) {
2188 InstanceKlass* intf = local_interfaces->at(i);
2189 if (!intf->has_passed_fingerprint_check()) {
2190 ResourceMark rm;
2191 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2192 return false;
2193 }
2194 }
2195 }
2196
2197 return true;
2198 }
2199
2200 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2201 #if INCLUDE_AOT
2202 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2203 if (CalculateClassFingerprint) {
2204 // (1) We are running AOT to generate a shared library.
2205 return true;
2206 }
2207 if (DumpSharedSpaces) {
2208 // (2) We are running -Xshare:dump to create a shared archive
2209 return true;
2210 }
2211 if (UseAOT && is_unsafe_anonymous) {
2212 // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2213 return true;
2214 }
2215 #endif
2216
2217 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2218 // but do not store the 64-bit fingerprint to save space.
2219 return false;
2220 }
2221
2222 bool InstanceKlass::has_stored_fingerprint() const {
2223 #if INCLUDE_AOT
2224 return should_store_fingerprint() || is_shared();
2225 #else
2226 return false;
2227 #endif
2228 }
2229
2230 uint64_t InstanceKlass::get_stored_fingerprint() const {
2231 address adr = adr_fingerprint();
2232 if (adr != NULL) {
2233 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2234 }
2235 return 0;
2236 }
2237
2238 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2239 address adr = adr_fingerprint();
2240 if (adr != NULL) {
2241 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2242
2243 ResourceMark rm;
2244 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2245 }
2246 }
2247
2248 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2249 Klass::metaspace_pointers_do(it);
2250
2251 if (log_is_enabled(Trace, cds)) {
2252 ResourceMark rm;
2253 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2254 }
2255
2256 it->push(&_annotations);
2257 it->push((Klass**)&_array_klasses);
2258 it->push(&_constants);
2259 it->push(&_inner_classes);
2260 it->push(&_array_name);
2261 #if INCLUDE_JVMTI
2262 it->push(&_previous_versions);
2263 #endif
2264 it->push(&_methods);
2265 it->push(&_default_methods);
2266 it->push(&_local_interfaces);
2267 it->push(&_transitive_interfaces);
2268 it->push(&_method_ordering);
2269 it->push(&_default_vtable_indices);
2270 it->push(&_fields);
2271
2272 if (itable_length() > 0) {
2273 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2274 int method_table_offset_in_words = ioe->offset()/wordSize;
2275 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2276 / itableOffsetEntry::size();
2277
2278 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2279 if (ioe->interface_klass() != NULL) {
2280 it->push(ioe->interface_klass_addr());
2281 itableMethodEntry* ime = ioe->first_method_entry(this);
2282 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2283 for (int index = 0; index < n; index ++) {
2284 it->push(ime[index].method_addr());
2285 }
2286 }
2287 }
2288 }
2289
2290 it->push(&_nest_members);
2291 }
2292
2293 void InstanceKlass::remove_unshareable_info() {
2294 Klass::remove_unshareable_info();
2295
2296 if (is_in_error_state()) {
2297 // Classes are attempted to link during dumping and may fail,
2298 // but these classes are still in the dictionary and class list in CLD.
2299 // Check in_error state first because in_error is > linked state, so
2300 // is_linked() is true.
2301 // If there's a linking error, there is nothing else to remove.
2302 return;
2303 }
2304
2305 // Unlink the class
2306 if (is_linked()) {
2307 unlink_class();
2308 }
2309 {
2310 MutexLocker ml(Compile_lock);
2311 init_implementor();
2312 }
2313
2314 constants()->remove_unshareable_info();
2315
2316 for (int i = 0; i < methods()->length(); i++) {
2317 Method* m = methods()->at(i);
2318 m->remove_unshareable_info();
2319 }
2320
2321 // do array classes also.
2322 if (array_klasses() != NULL) {
2323 array_klasses()->remove_unshareable_info();
2324 }
2325
2326 // These are not allocated from metaspace, but they should should all be empty
2327 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2328 guarantee(_source_debug_extension == NULL, "must be");
2329 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2330 guarantee(_osr_nmethods_head == NULL, "must be");
2331
2332 #if INCLUDE_JVMTI
2333 guarantee(_breakpoints == NULL, "must be");
2334 guarantee(_previous_versions == NULL, "must be");
2335 #endif
2336
2337 _init_thread = NULL;
2338 _methods_jmethod_ids = NULL;
2339 _jni_ids = NULL;
2340 _oop_map_cache = NULL;
2341 // clear _nest_host to ensure re-load at runtime
2342 _nest_host = NULL;
2343 }
2344
2345 void InstanceKlass::remove_java_mirror() {
2346 Klass::remove_java_mirror();
2347
2348 // do array classes also.
2349 if (array_klasses() != NULL) {
2350 array_klasses()->remove_java_mirror();
2351 }
2352 }
2353
2354 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2355 set_package(loader_data, CHECK);
2356 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2357
2358 Array<Method*>* methods = this->methods();
2359 int num_methods = methods->length();
2360 for (int index2 = 0; index2 < num_methods; ++index2) {
2361 methodHandle m(THREAD, methods->at(index2));
2362 m->restore_unshareable_info(CHECK);
2363 }
2364 if (JvmtiExport::has_redefined_a_class()) {
2365 // Reinitialize vtable because RedefineClasses may have changed some
2366 // entries in this vtable for super classes so the CDS vtable might
2367 // point to old or obsolete entries. RedefineClasses doesn't fix up
2368 // vtables in the shared system dictionary, only the main one.
2369 // It also redefines the itable too so fix that too.
2370 vtable().initialize_vtable(false, CHECK);
2371 itable().initialize_itable(false, CHECK);
2372 }
2373
2374 // restore constant pool resolved references
2375 constants()->restore_unshareable_info(CHECK);
2376
2377 if (array_klasses() != NULL) {
2378 // Array classes have null protection domain.
2379 // --> see ArrayKlass::complete_create_array_klass()
2380 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2381 }
2382 }
2383
2384 // returns true IFF is_in_error_state() has been changed as a result of this call.
2385 bool InstanceKlass::check_sharing_error_state() {
2386 assert(DumpSharedSpaces, "should only be called during dumping");
2387 bool old_state = is_in_error_state();
2388
2389 if (!is_in_error_state()) {
2390 bool bad = false;
2391 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2392 if (sup->is_in_error_state()) {
2393 bad = true;
2394 break;
2395 }
2396 }
2397 if (!bad) {
2398 Array<InstanceKlass*>* interfaces = transitive_interfaces();
2399 for (int i = 0; i < interfaces->length(); i++) {
2400 InstanceKlass* iface = interfaces->at(i);
2401 if (iface->is_in_error_state()) {
2402 bad = true;
2403 break;
2404 }
2405 }
2406 }
2407
2408 if (bad) {
2409 set_in_error_state();
2410 }
2411 }
2412
2413 return (old_state != is_in_error_state());
2414 }
2415
2416 #if INCLUDE_JVMTI
2417 static void clear_all_breakpoints(Method* m) {
2418 m->clear_all_breakpoints();
2419 }
2420 #endif
2421
2422 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2423 // notify the debugger
2424 if (JvmtiExport::should_post_class_unload()) {
2425 JvmtiExport::post_class_unload(ik);
2426 }
2427
2428 // notify ClassLoadingService of class unload
2429 ClassLoadingService::notify_class_unloaded(ik);
2430
2431 #if INCLUDE_JFR
2432 assert(ik != NULL, "invariant");
2433 EventClassUnload event;
2434 event.set_unloadedClass(ik);
2435 event.set_definingClassLoader(ik->class_loader_data());
2436 event.commit();
2437 #endif
2438 }
2439
2440 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2441 // Clean up C heap
2442 ik->release_C_heap_structures();
2443 ik->constants()->release_C_heap_structures();
2444 }
2445
2446 void InstanceKlass::release_C_heap_structures() {
2447 // Can't release the constant pool here because the constant pool can be
2448 // deallocated separately from the InstanceKlass for default methods and
2449 // redefine classes.
2450
2451 // Deallocate oop map cache
2452 if (_oop_map_cache != NULL) {
2453 delete _oop_map_cache;
2454 _oop_map_cache = NULL;
2455 }
2456
2457 // Deallocate JNI identifiers for jfieldIDs
2458 JNIid::deallocate(jni_ids());
2459 set_jni_ids(NULL);
2460
2461 jmethodID* jmeths = methods_jmethod_ids_acquire();
2462 if (jmeths != (jmethodID*)NULL) {
2463 release_set_methods_jmethod_ids(NULL);
2464 FreeHeap(jmeths);
2465 }
2466
2467 // Release dependencies.
2468 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2469 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2470 // context can contain live dependencies, since there's a race between nmethod &
2471 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2472 // dependencies aren't removed from the context associated with the class (see
2473 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2474 // live dependencies pointing to unloaded nmethods and causes a crash in
2475 // DC::remove_all_dependents() when it touches unloaded nmethod.
2476 dependencies().wipe();
2477
2478 #if INCLUDE_JVMTI
2479 // Deallocate breakpoint records
2480 if (breakpoints() != 0x0) {
2481 methods_do(clear_all_breakpoints);
2482 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2483 }
2484
2485 // deallocate the cached class file
2486 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2487 os::free(_cached_class_file);
2488 _cached_class_file = NULL;
2489 }
2490 #endif
2491
2492 // Decrement symbol reference counts associated with the unloaded class.
2493 if (_name != NULL) _name->decrement_refcount();
2494 // unreference array name derived from this class name (arrays of an unloaded
2495 // class can't be referenced anymore).
2496 if (_array_name != NULL) _array_name->decrement_refcount();
2497 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2498 }
2499
2500 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2501 if (array == NULL) {
2502 _source_debug_extension = NULL;
2503 } else {
2504 // Adding one to the attribute length in order to store a null terminator
2505 // character could cause an overflow because the attribute length is
2506 // already coded with an u4 in the classfile, but in practice, it's
2507 // unlikely to happen.
2508 assert((length+1) > length, "Overflow checking");
2509 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2510 for (int i = 0; i < length; i++) {
2511 sde[i] = array[i];
2512 }
2513 sde[length] = '\0';
2514 _source_debug_extension = sde;
2515 }
2516 }
2517
2518 const char* InstanceKlass::signature_name() const {
2519 int hash_len = 0;
2520 char hash_buf[40];
2521
2522 // If this is an unsafe anonymous class, append a hash to make the name unique
2523 if (is_unsafe_anonymous()) {
2524 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2525 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2526 hash_len = (int)strlen(hash_buf);
2527 }
2528
2529 // Get the internal name as a c string
2530 const char* src = (const char*) (name()->as_C_string());
2531 const int src_length = (int)strlen(src);
2532
2533 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2534
2535 // Add L as type indicator
2536 int dest_index = 0;
2537 dest[dest_index++] = 'L';
2538
2539 // Add the actual class name
2540 for (int src_index = 0; src_index < src_length; ) {
2541 dest[dest_index++] = src[src_index++];
2542 }
2543
2544 // If we have a hash, append it
2545 for (int hash_index = 0; hash_index < hash_len; ) {
2546 dest[dest_index++] = hash_buf[hash_index++];
2547 }
2548
2549 // Add the semicolon and the NULL
2550 dest[dest_index++] = ';';
2551 dest[dest_index] = '\0';
2552 return dest;
2553 }
2554
2555 // Used to obtain the package name from a fully qualified class name.
2556 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2557 if (name == NULL) {
2558 return NULL;
2559 } else {
2560 if (name->utf8_length() <= 0) {
2561 return NULL;
2562 }
2563 ResourceMark rm;
2564 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2565 if (package_name == NULL) {
2566 return NULL;
2567 }
2568 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2569 return pkg_name;
2570 }
2571 }
2572
2573 ModuleEntry* InstanceKlass::module() const {
2574 // For an unsafe anonymous class return the host class' module
2575 if (is_unsafe_anonymous()) {
2576 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2577 return unsafe_anonymous_host()->module();
2578 }
2579
2580 // Class is in a named package
2581 if (!in_unnamed_package()) {
2582 return _package_entry->module();
2583 }
2584
2585 // Class is in an unnamed package, return its loader's unnamed module
2586 return class_loader_data()->unnamed_module();
2587 }
2588
2589 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2590
2591 // ensure java/ packages only loaded by boot or platform builtin loaders
2592 check_prohibited_package(name(), loader_data, CHECK);
2593
2594 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2595
2596 if (pkg_name != NULL && loader_data != NULL) {
2597
2598 // Find in class loader's package entry table.
2599 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2600
2601 // If the package name is not found in the loader's package
2602 // entry table, it is an indication that the package has not
2603 // been defined. Consider it defined within the unnamed module.
2604 if (_package_entry == NULL) {
2605 ResourceMark rm;
2606
2607 if (!ModuleEntryTable::javabase_defined()) {
2608 // Before java.base is defined during bootstrapping, define all packages in
2609 // the java.base module. If a non-java.base package is erroneously placed
2610 // in the java.base module it will be caught later when java.base
2611 // is defined by ModuleEntryTable::verify_javabase_packages check.
2612 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2613 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2614 } else {
2615 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2616 _package_entry = loader_data->packages()->lookup(pkg_name,
2617 loader_data->unnamed_module());
2618 }
2619
2620 // A package should have been successfully created
2621 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2622 name()->as_C_string(), loader_data->loader_name_and_id());
2623 }
2624
2625 if (log_is_enabled(Debug, module)) {
2626 ResourceMark rm;
2627 ModuleEntry* m = _package_entry->module();
2628 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2629 external_name(),
2630 pkg_name->as_C_string(),
2631 loader_data->loader_name_and_id(),
2632 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2633 }
2634 } else {
2635 ResourceMark rm;
2636 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2637 external_name(),
2638 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2639 UNNAMED_MODULE);
2640 }
2641 }
2642
2643
2644 // different versions of is_same_class_package
2645
2646 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2647 oop classloader1 = this->class_loader();
2648 PackageEntry* classpkg1 = this->package();
2649 if (class2->is_objArray_klass()) {
2650 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2651 }
2652
2653 oop classloader2;
2654 PackageEntry* classpkg2;
2655 if (class2->is_instance_klass()) {
2656 classloader2 = class2->class_loader();
2657 classpkg2 = class2->package();
2658 } else {
2659 assert(class2->is_typeArray_klass(), "should be type array");
2660 classloader2 = NULL;
2661 classpkg2 = NULL;
2662 }
2663
2664 // Same package is determined by comparing class loader
2665 // and package entries. Both must be the same. This rule
2666 // applies even to classes that are defined in the unnamed
2667 // package, they still must have the same class loader.
2668 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2669 return true;
2670 }
2671
2672 return false;
2673 }
2674
2675 // return true if this class and other_class are in the same package. Classloader
2676 // and classname information is enough to determine a class's package
2677 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2678 const Symbol* other_class_name) const {
2679 if (!oopDesc::equals(class_loader(), other_class_loader)) {
2680 return false;
2681 }
2682 if (name()->fast_compare(other_class_name) == 0) {
2683 return true;
2684 }
2685
2686 {
2687 ResourceMark rm;
2688
2689 bool bad_class_name = false;
2690 const char* other_pkg =
2691 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2692 if (bad_class_name) {
2693 return false;
2694 }
2695 // Check that package_from_name() returns NULL, not "", if there is no package.
2696 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2697
2698 const Symbol* const this_package_name =
2699 this->package() != NULL ? this->package()->name() : NULL;
2700
2701 if (this_package_name == NULL || other_pkg == NULL) {
2702 // One of the two doesn't have a package. Only return true if the other
2703 // one also doesn't have a package.
2704 return (const char*)this_package_name == other_pkg;
2705 }
2706
2707 // Check if package is identical
2708 return this_package_name->equals(other_pkg);
2709 }
2710 }
2711
2712 // Returns true iff super_method can be overridden by a method in targetclassname
2713 // See JLS 3rd edition 8.4.6.1
2714 // Assumes name-signature match
2715 // "this" is InstanceKlass of super_method which must exist
2716 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2717 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2718 // Private methods can not be overridden
2719 if (super_method->is_private()) {
2720 return false;
2721 }
2722 // If super method is accessible, then override
2723 if ((super_method->is_protected()) ||
2724 (super_method->is_public())) {
2725 return true;
2726 }
2727 // Package-private methods are not inherited outside of package
2728 assert(super_method->is_package_private(), "must be package private");
2729 return(is_same_class_package(targetclassloader(), targetclassname));
2730 }
2731
2732 // Only boot and platform class loaders can define classes in "java/" packages.
2733 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2734 ClassLoaderData* loader_data,
2735 TRAPS) {
2736 if (!loader_data->is_boot_class_loader_data() &&
2737 !loader_data->is_platform_class_loader_data() &&
2738 class_name != NULL) {
2739 ResourceMark rm(THREAD);
2740 char* name = class_name->as_C_string();
2741 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2742 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2743 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2744 name = pkg_name->as_C_string();
2745 const char* class_loader_name = loader_data->loader_name_and_id();
2746 StringUtils::replace_no_expand(name, "/", ".");
2747 const char* msg_text1 = "Class loader (instance of): ";
2748 const char* msg_text2 = " tried to load prohibited package name: ";
2749 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2750 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2751 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2752 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2753 }
2754 }
2755 return;
2756 }
2757
2758 // tell if two classes have the same enclosing class (at package level)
2759 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2760 if (class2 == this) return true;
2761 if (!class2->is_instance_klass()) return false;
2762
2763 // must be in same package before we try anything else
2764 if (!is_same_class_package(class2))
2765 return false;
2766
2767 // As long as there is an outer_this.getEnclosingClass,
2768 // shift the search outward.
2769 const InstanceKlass* outer_this = this;
2770 for (;;) {
2771 // As we walk along, look for equalities between outer_this and class2.
2772 // Eventually, the walks will terminate as outer_this stops
2773 // at the top-level class around the original class.
2774 bool ignore_inner_is_member;
2775 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2776 CHECK_false);
2777 if (next == NULL) break;
2778 if (next == class2) return true;
2779 outer_this = InstanceKlass::cast(next);
2780 }
2781
2782 // Now do the same for class2.
2783 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2784 for (;;) {
2785 bool ignore_inner_is_member;
2786 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2787 CHECK_false);
2788 if (next == NULL) break;
2789 // Might as well check the new outer against all available values.
2790 if (next == this) return true;
2791 if (next == outer_this) return true;
2792 outer2 = InstanceKlass::cast(next);
2793 }
2794
2795 // If by this point we have not found an equality between the
2796 // two classes, we know they are in separate package members.
2797 return false;
2798 }
2799
2800 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2801 constantPoolHandle i_cp(THREAD, constants());
2802 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2803 int ioff = iter.inner_class_info_index();
2804 if (ioff != 0) {
2805 // Check to see if the name matches the class we're looking for
2806 // before attempting to find the class.
2807 if (i_cp->klass_name_at_matches(this, ioff)) {
2808 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2809 if (this == inner_klass) {
2810 *ooff = iter.outer_class_info_index();
2811 *noff = iter.inner_name_index();
2812 return true;
2813 }
2814 }
2815 }
2816 }
2817 return false;
2818 }
2819
2820 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2821 InstanceKlass* outer_klass = NULL;
2822 *inner_is_member = false;
2823 int ooff = 0, noff = 0;
2824 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2825 if (has_inner_classes_attr) {
2826 constantPoolHandle i_cp(THREAD, constants());
2827 if (ooff != 0) {
2828 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2829 outer_klass = InstanceKlass::cast(ok);
2830 *inner_is_member = true;
2831 }
2832 if (NULL == outer_klass) {
2833 // It may be unsafe anonymous; try for that.
2834 int encl_method_class_idx = enclosing_method_class_index();
2835 if (encl_method_class_idx != 0) {
2836 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2837 outer_klass = InstanceKlass::cast(ok);
2838 *inner_is_member = false;
2839 }
2840 }
2841 }
2842
2843 // If no inner class attribute found for this class.
2844 if (NULL == outer_klass) return NULL;
2845
2846 // Throws an exception if outer klass has not declared k as an inner klass
2847 // We need evidence that each klass knows about the other, or else
2848 // the system could allow a spoof of an inner class to gain access rights.
2849 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2850 return outer_klass;
2851 }
2852
2853 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2854 jint access = access_flags().as_int();
2855
2856 // But check if it happens to be member class.
2857 InnerClassesIterator iter(this);
2858 for (; !iter.done(); iter.next()) {
2859 int ioff = iter.inner_class_info_index();
2860 // Inner class attribute can be zero, skip it.
2861 // Strange but true: JVM spec. allows null inner class refs.
2862 if (ioff == 0) continue;
2863
2864 // only look at classes that are already loaded
2865 // since we are looking for the flags for our self.
2866 Symbol* inner_name = constants()->klass_name_at(ioff);
2867 if (name() == inner_name) {
2868 // This is really a member class.
2869 access = iter.inner_access_flags();
2870 break;
2871 }
2872 }
2873 // Remember to strip ACC_SUPER bit
2874 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2875 }
2876
2877 jint InstanceKlass::jvmti_class_status() const {
2878 jint result = 0;
2879
2880 if (is_linked()) {
2881 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2882 }
2883
2884 if (is_initialized()) {
2885 assert(is_linked(), "Class status is not consistent");
2886 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2887 }
2888 if (is_in_error_state()) {
2889 result |= JVMTI_CLASS_STATUS_ERROR;
2890 }
2891 return result;
2892 }
2893
2894 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2895 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2896 int method_table_offset_in_words = ioe->offset()/wordSize;
2897 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2898 / itableOffsetEntry::size();
2899
2900 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2901 // If the interface isn't implemented by the receiver class,
2902 // the VM should throw IncompatibleClassChangeError.
2903 if (cnt >= nof_interfaces) {
2904 ResourceMark rm(THREAD);
2905 stringStream ss;
2906 bool same_module = (module() == holder->module());
2907 ss.print("Receiver class %s does not implement "
2908 "the interface %s defining the method to be called "
2909 "(%s%s%s)",
2910 external_name(), holder->external_name(),
2911 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2912 (same_module) ? "" : "; ",
2913 (same_module) ? "" : holder->class_in_module_of_loader());
2914 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2915 }
2916
2917 Klass* ik = ioe->interface_klass();
2918 if (ik == holder) break;
2919 }
2920
2921 itableMethodEntry* ime = ioe->first_method_entry(this);
2922 Method* m = ime[index].method();
2923 if (m == NULL) {
2924 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2925 }
2926 return m;
2927 }
2928
2929
2930 #if INCLUDE_JVMTI
2931 // update default_methods for redefineclasses for methods that are
2932 // not yet in the vtable due to concurrent subclass define and superinterface
2933 // redefinition
2934 // Note: those in the vtable, should have been updated via adjust_method_entries
2935 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2936 // search the default_methods for uses of either obsolete or EMCP methods
2937 if (default_methods() != NULL) {
2938 for (int index = 0; index < default_methods()->length(); index ++) {
2939 Method* old_method = default_methods()->at(index);
2940 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2941 continue; // skip uninteresting entries
2942 }
2943 assert(!old_method->is_deleted(), "default methods may not be deleted");
2944
2945 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2946
2947 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2948 assert(old_method != new_method, "sanity check");
2949
2950 default_methods()->at_put(index, new_method);
2951 if (log_is_enabled(Info, redefine, class, update)) {
2952 ResourceMark rm;
2953 if (!(*trace_name_printed)) {
2954 log_info(redefine, class, update)
2955 ("adjust: klassname=%s default methods from name=%s",
2956 external_name(), old_method->method_holder()->external_name());
2957 *trace_name_printed = true;
2958 }
2959 log_debug(redefine, class, update, vtables)
2960 ("default method update: %s(%s) ",
2961 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2962 }
2963 }
2964 }
2965 }
2966 #endif // INCLUDE_JVMTI
2967
2968 // On-stack replacement stuff
2969 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2970 // only one compilation can be active
2971 {
2972 // This is a short non-blocking critical region, so the no safepoint check is ok.
2973 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2974 assert(n->is_osr_method(), "wrong kind of nmethod");
2975 n->set_osr_link(osr_nmethods_head());
2976 set_osr_nmethods_head(n);
2977 // Raise the highest osr level if necessary
2978 if (TieredCompilation) {
2979 Method* m = n->method();
2980 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2981 }
2982 }
2983
2984 // Get rid of the osr methods for the same bci that have lower levels.
2985 if (TieredCompilation) {
2986 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2987 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2988 if (inv != NULL && inv->is_in_use()) {
2989 inv->make_not_entrant();
2990 }
2991 }
2992 }
2993 }
2994
2995 // Remove osr nmethod from the list. Return true if found and removed.
2996 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2997 // This is a short non-blocking critical region, so the no safepoint check is ok.
2998 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2999 assert(n->is_osr_method(), "wrong kind of nmethod");
3000 nmethod* last = NULL;
3001 nmethod* cur = osr_nmethods_head();
3002 int max_level = CompLevel_none; // Find the max comp level excluding n
3003 Method* m = n->method();
3004 // Search for match
3005 bool found = false;
3006 while(cur != NULL && cur != n) {
3007 if (TieredCompilation && m == cur->method()) {
3008 // Find max level before n
3009 max_level = MAX2(max_level, cur->comp_level());
3010 }
3011 last = cur;
3012 cur = cur->osr_link();
3013 }
3014 nmethod* next = NULL;
3015 if (cur == n) {
3016 found = true;
3017 next = cur->osr_link();
3018 if (last == NULL) {
3019 // Remove first element
3020 set_osr_nmethods_head(next);
3021 } else {
3022 last->set_osr_link(next);
3023 }
3024 }
3025 n->set_osr_link(NULL);
3026 if (TieredCompilation) {
3027 cur = next;
3028 while (cur != NULL) {
3029 // Find max level after n
3030 if (m == cur->method()) {
3031 max_level = MAX2(max_level, cur->comp_level());
3032 }
3033 cur = cur->osr_link();
3034 }
3035 m->set_highest_osr_comp_level(max_level);
3036 }
3037 return found;
3038 }
3039
3040 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3041 // This is a short non-blocking critical region, so the no safepoint check is ok.
3042 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3043 nmethod* osr = osr_nmethods_head();
3044 int found = 0;
3045 while (osr != NULL) {
3046 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3047 if (osr->method() == m) {
3048 osr->mark_for_deoptimization();
3049 found++;
3050 }
3051 osr = osr->osr_link();
3052 }
3053 return found;
3054 }
3055
3056 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3057 // This is a short non-blocking critical region, so the no safepoint check is ok.
3058 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3059 nmethod* osr = osr_nmethods_head();
3060 nmethod* best = NULL;
3061 while (osr != NULL) {
3062 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3063 // There can be a time when a c1 osr method exists but we are waiting
3064 // for a c2 version. When c2 completes its osr nmethod we will trash
3065 // the c1 version and only be able to find the c2 version. However
3066 // while we overflow in the c1 code at back branches we don't want to
3067 // try and switch to the same code as we are already running
3068
3069 if (osr->method() == m &&
3070 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3071 if (match_level) {
3072 if (osr->comp_level() == comp_level) {
3073 // Found a match - return it.
3074 return osr;
3075 }
3076 } else {
3077 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3078 if (osr->comp_level() == CompLevel_highest_tier) {
3079 // Found the best possible - return it.
3080 return osr;
3081 }
3082 best = osr;
3083 }
3084 }
3085 }
3086 osr = osr->osr_link();
3087 }
3088 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3089 return best;
3090 }
3091 return NULL;
3092 }
3093
3094 // -----------------------------------------------------------------------------------------------------
3095 // Printing
3096
3097 #ifndef PRODUCT
3098
3099 #define BULLET " - "
3100
3101 static const char* state_names[] = {
3102 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3103 };
3104
3105 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3106 for (int i = 0; i < len; i++) {
3107 intptr_t e = start[i];
3108 st->print("%d : " INTPTR_FORMAT, i, e);
3109 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3110 st->print(" ");
3111 ((Metadata*)e)->print_value_on(st);
3112 }
3113 st->cr();
3114 }
3115 }
3116
3117 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3118 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3119 }
3120
3121 void InstanceKlass::print_on(outputStream* st) const {
3122 assert(is_klass(), "must be klass");
3123 Klass::print_on(st);
3124
3125 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3126 st->print(BULLET"klass size: %d", size()); st->cr();
3127 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3128 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3129 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3130 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3131 st->print(BULLET"sub: ");
3132 Klass* sub = subklass();
3133 int n;
3134 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3135 if (n < MaxSubklassPrintSize) {
3136 sub->print_value_on(st);
3137 st->print(" ");
3138 }
3139 }
3140 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3141 st->cr();
3142
3143 if (is_interface()) {
3144 MutexLocker ml(Compile_lock);
3145 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3146 if (nof_implementors() == 1) {
3147 st->print_cr(BULLET"implementor: ");
3148 st->print(" ");
3149 implementor()->print_value_on(st);
3150 st->cr();
3151 }
3152 }
3153
3154 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3155 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3156 if (Verbose || WizardMode) {
3157 Array<Method*>* method_array = methods();
3158 for (int i = 0; i < method_array->length(); i++) {
3159 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3160 }
3161 }
3162 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3163 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3164 if (Verbose && default_methods() != NULL) {
3165 Array<Method*>* method_array = default_methods();
3166 for (int i = 0; i < method_array->length(); i++) {
3167 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3168 }
3169 }
3170 if (default_vtable_indices() != NULL) {
3171 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3172 }
3173 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3174 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3175 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3176 if (class_loader_data() != NULL) {
3177 st->print(BULLET"class loader data: ");
3178 class_loader_data()->print_value_on(st);
3179 st->cr();
3180 }
3181 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3182 if (source_file_name() != NULL) {
3183 st->print(BULLET"source file: ");
3184 source_file_name()->print_value_on(st);
3185 st->cr();
3186 }
3187 if (source_debug_extension() != NULL) {
3188 st->print(BULLET"source debug extension: ");
3189 st->print("%s", source_debug_extension());
3190 st->cr();
3191 }
3192 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3193 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3194 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3195 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3196 {
3197 bool have_pv = false;
3198 // previous versions are linked together through the InstanceKlass
3199 for (InstanceKlass* pv_node = previous_versions();
3200 pv_node != NULL;
3201 pv_node = pv_node->previous_versions()) {
3202 if (!have_pv)
3203 st->print(BULLET"previous version: ");
3204 have_pv = true;
3205 pv_node->constants()->print_value_on(st);
3206 }
3207 if (have_pv) st->cr();
3208 }
3209
3210 if (generic_signature() != NULL) {
3211 st->print(BULLET"generic signature: ");
3212 generic_signature()->print_value_on(st);
3213 st->cr();
3214 }
3215 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3216 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3217 if (java_mirror() != NULL) {
3218 st->print(BULLET"java mirror: ");
3219 java_mirror()->print_value_on(st);
3220 st->cr();
3221 } else {
3222 st->print_cr(BULLET"java mirror: NULL");
3223 }
3224 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3225 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3226 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3227 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3228 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3229 FieldPrinter print_static_field(st);
3230 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3231 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3232 FieldPrinter print_nonstatic_field(st);
3233 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3234 ik->do_nonstatic_fields(&print_nonstatic_field);
3235
3236 st->print(BULLET"non-static oop maps: ");
3237 OopMapBlock* map = start_of_nonstatic_oop_maps();
3238 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3239 while (map < end_map) {
3240 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3241 map++;
3242 }
3243 st->cr();
3244 }
3245
3246 #endif //PRODUCT
3247
3248 void InstanceKlass::print_value_on(outputStream* st) const {
3249 assert(is_klass(), "must be klass");
3250 if (Verbose || WizardMode) access_flags().print_on(st);
3251 name()->print_value_on(st);
3252 }
3253
3254 #ifndef PRODUCT
3255
3256 void FieldPrinter::do_field(fieldDescriptor* fd) {
3257 _st->print(BULLET);
3258 if (_obj == NULL) {
3259 fd->print_on(_st);
3260 _st->cr();
3261 } else {
3262 fd->print_on_for(_st, _obj);
3263 _st->cr();
3264 }
3265 }
3266
3267
3268 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3269 Klass::oop_print_on(obj, st);
3270
3271 if (this == SystemDictionary::String_klass()) {
3272 typeArrayOop value = java_lang_String::value(obj);
3273 juint length = java_lang_String::length(obj);
3274 if (value != NULL &&
3275 value->is_typeArray() &&
3276 length <= (juint) value->length()) {
3277 st->print(BULLET"string: ");
3278 java_lang_String::print(obj, st);
3279 st->cr();
3280 if (!WizardMode) return; // that is enough
3281 }
3282 }
3283
3284 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3285 FieldPrinter print_field(st, obj);
3286 do_nonstatic_fields(&print_field);
3287
3288 if (this == SystemDictionary::Class_klass()) {
3289 st->print(BULLET"signature: ");
3290 java_lang_Class::print_signature(obj, st);
3291 st->cr();
3292 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3293 st->print(BULLET"fake entry for mirror: ");
3294 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3295 st->cr();
3296 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3297 st->print(BULLET"fake entry for array: ");
3298 Metadata::print_value_on_maybe_null(st, array_klass);
3299 st->cr();
3300 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3301 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3302 Klass* real_klass = java_lang_Class::as_Klass(obj);
3303 if (real_klass != NULL && real_klass->is_instance_klass()) {
3304 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3305 }
3306 } else if (this == SystemDictionary::MethodType_klass()) {
3307 st->print(BULLET"signature: ");
3308 java_lang_invoke_MethodType::print_signature(obj, st);
3309 st->cr();
3310 }
3311 }
3312
3313 bool InstanceKlass::verify_itable_index(int i) {
3314 int method_count = klassItable::method_count_for_interface(this);
3315 assert(i >= 0 && i < method_count, "index out of bounds");
3316 return true;
3317 }
3318
3319 #endif //PRODUCT
3320
3321 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3322 st->print("a ");
3323 name()->print_value_on(st);
3324 obj->print_address_on(st);
3325 if (this == SystemDictionary::String_klass()
3326 && java_lang_String::value(obj) != NULL) {
3327 ResourceMark rm;
3328 int len = java_lang_String::length(obj);
3329 int plen = (len < 24 ? len : 12);
3330 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3331 st->print(" = \"%s\"", str);
3332 if (len > plen)
3333 st->print("...[%d]", len);
3334 } else if (this == SystemDictionary::Class_klass()) {
3335 Klass* k = java_lang_Class::as_Klass(obj);
3336 st->print(" = ");
3337 if (k != NULL) {
3338 k->print_value_on(st);
3339 } else {
3340 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3341 st->print("%s", tname ? tname : "type?");
3342 }
3343 } else if (this == SystemDictionary::MethodType_klass()) {
3344 st->print(" = ");
3345 java_lang_invoke_MethodType::print_signature(obj, st);
3346 } else if (java_lang_boxing_object::is_instance(obj)) {
3347 st->print(" = ");
3348 java_lang_boxing_object::print(obj, st);
3349 } else if (this == SystemDictionary::LambdaForm_klass()) {
3350 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3351 if (vmentry != NULL) {
3352 st->print(" => ");
3353 vmentry->print_value_on(st);
3354 }
3355 } else if (this == SystemDictionary::MemberName_klass()) {
3356 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3357 if (vmtarget != NULL) {
3358 st->print(" = ");
3359 vmtarget->print_value_on(st);
3360 } else {
3361 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3362 st->print(".");
3363 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3364 }
3365 }
3366 }
3367
3368 const char* InstanceKlass::internal_name() const {
3369 return external_name();
3370 }
3371
3372 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3373 const char* module_name,
3374 const ClassFileStream* cfs) const {
3375 if (!log_is_enabled(Info, class, load)) {
3376 return;
3377 }
3378
3379 ResourceMark rm;
3380 LogMessage(class, load) msg;
3381 stringStream info_stream;
3382
3383 // Name and class hierarchy info
3384 info_stream.print("%s", external_name());
3385
3386 // Source
3387 if (cfs != NULL) {
3388 if (cfs->source() != NULL) {
3389 if (module_name != NULL) {
3390 if (ClassLoader::is_modules_image(cfs->source())) {
3391 info_stream.print(" source: jrt:/%s", module_name);
3392 } else {
3393 info_stream.print(" source: %s", cfs->source());
3394 }
3395 } else {
3396 info_stream.print(" source: %s", cfs->source());
3397 }
3398 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3399 Thread* THREAD = Thread::current();
3400 Klass* caller =
3401 THREAD->is_Java_thread()
3402 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3403 : NULL;
3404 // caller can be NULL, for example, during a JVMTI VM_Init hook
3405 if (caller != NULL) {
3406 info_stream.print(" source: instance of %s", caller->external_name());
3407 } else {
3408 // source is unknown
3409 }
3410 } else {
3411 oop class_loader = loader_data->class_loader();
3412 info_stream.print(" source: %s", class_loader->klass()->external_name());
3413 }
3414 } else {
3415 info_stream.print(" source: shared objects file");
3416 }
3417
3418 msg.info("%s", info_stream.as_string());
3419
3420 if (log_is_enabled(Debug, class, load)) {
3421 stringStream debug_stream;
3422
3423 // Class hierarchy info
3424 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3425 p2i(this), p2i(superklass()));
3426
3427 // Interfaces
3428 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3429 debug_stream.print(" interfaces:");
3430 int length = local_interfaces()->length();
3431 for (int i = 0; i < length; i++) {
3432 debug_stream.print(" " INTPTR_FORMAT,
3433 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3434 }
3435 }
3436
3437 // Class loader
3438 debug_stream.print(" loader: [");
3439 loader_data->print_value_on(&debug_stream);
3440 debug_stream.print("]");
3441
3442 // Classfile checksum
3443 if (cfs) {
3444 debug_stream.print(" bytes: %d checksum: %08x",
3445 cfs->length(),
3446 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3447 cfs->length()));
3448 }
3449
3450 msg.debug("%s", debug_stream.as_string());
3451 }
3452 }
3453
3454 #if INCLUDE_SERVICES
3455 // Size Statistics
3456 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3457 Klass::collect_statistics(sz);
3458
3459 sz->_inst_size = wordSize * size_helper();
3460 sz->_vtab_bytes = wordSize * vtable_length();
3461 sz->_itab_bytes = wordSize * itable_length();
3462 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3463
3464 int n = 0;
3465 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3466 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3467 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3468 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3469 n += (sz->_fields_bytes = sz->count_array(fields()));
3470 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3471 n += (sz->_nest_members_bytes = sz->count_array(nest_members()));
3472 sz->_ro_bytes += n;
3473
3474 const ConstantPool* cp = constants();
3475 if (cp) {
3476 cp->collect_statistics(sz);
3477 }
3478
3479 const Annotations* anno = annotations();
3480 if (anno) {
3481 anno->collect_statistics(sz);
3482 }
3483
3484 const Array<Method*>* methods_array = methods();
3485 if (methods()) {
3486 for (int i = 0; i < methods_array->length(); i++) {
3487 Method* method = methods_array->at(i);
3488 if (method) {
3489 sz->_method_count ++;
3490 method->collect_statistics(sz);
3491 }
3492 }
3493 }
3494 }
3495 #endif // INCLUDE_SERVICES
3496
3497 // Verification
3498
3499 class VerifyFieldClosure: public BasicOopIterateClosure {
3500 protected:
3501 template <class T> void do_oop_work(T* p) {
3502 oop obj = RawAccess<>::oop_load(p);
3503 if (!oopDesc::is_oop_or_null(obj)) {
3504 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3505 Universe::print_on(tty);
3506 guarantee(false, "boom");
3507 }
3508 }
3509 public:
3510 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3511 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3512 };
3513
3514 void InstanceKlass::verify_on(outputStream* st) {
3515 #ifndef PRODUCT
3516 // Avoid redundant verifies, this really should be in product.
3517 if (_verify_count == Universe::verify_count()) return;
3518 _verify_count = Universe::verify_count();
3519 #endif
3520
3521 // Verify Klass
3522 Klass::verify_on(st);
3523
3524 // Verify that klass is present in ClassLoaderData
3525 guarantee(class_loader_data()->contains_klass(this),
3526 "this class isn't found in class loader data");
3527
3528 // Verify vtables
3529 if (is_linked()) {
3530 // $$$ This used to be done only for m/s collections. Doing it
3531 // always seemed a valid generalization. (DLD -- 6/00)
3532 vtable().verify(st);
3533 }
3534
3535 // Verify first subklass
3536 if (subklass() != NULL) {
3537 guarantee(subklass()->is_klass(), "should be klass");
3538 }
3539
3540 // Verify siblings
3541 Klass* super = this->super();
3542 Klass* sib = next_sibling();
3543 if (sib != NULL) {
3544 if (sib == this) {
3545 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3546 }
3547
3548 guarantee(sib->is_klass(), "should be klass");
3549 guarantee(sib->super() == super, "siblings should have same superklass");
3550 }
3551
3552 // Verify implementor fields requires the Compile_lock, but this is sometimes
3553 // called inside a safepoint, so don't verify.
3554
3555 // Verify local interfaces
3556 if (local_interfaces()) {
3557 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3558 for (int j = 0; j < local_interfaces->length(); j++) {
3559 InstanceKlass* e = local_interfaces->at(j);
3560 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3561 }
3562 }
3563
3564 // Verify transitive interfaces
3565 if (transitive_interfaces() != NULL) {
3566 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3567 for (int j = 0; j < transitive_interfaces->length(); j++) {
3568 InstanceKlass* e = transitive_interfaces->at(j);
3569 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3570 }
3571 }
3572
3573 // Verify methods
3574 if (methods() != NULL) {
3575 Array<Method*>* methods = this->methods();
3576 for (int j = 0; j < methods->length(); j++) {
3577 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3578 }
3579 for (int j = 0; j < methods->length() - 1; j++) {
3580 Method* m1 = methods->at(j);
3581 Method* m2 = methods->at(j + 1);
3582 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3583 }
3584 }
3585
3586 // Verify method ordering
3587 if (method_ordering() != NULL) {
3588 Array<int>* method_ordering = this->method_ordering();
3589 int length = method_ordering->length();
3590 if (JvmtiExport::can_maintain_original_method_order() ||
3591 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3592 guarantee(length == methods()->length(), "invalid method ordering length");
3593 jlong sum = 0;
3594 for (int j = 0; j < length; j++) {
3595 int original_index = method_ordering->at(j);
3596 guarantee(original_index >= 0, "invalid method ordering index");
3597 guarantee(original_index < length, "invalid method ordering index");
3598 sum += original_index;
3599 }
3600 // Verify sum of indices 0,1,...,length-1
3601 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3602 } else {
3603 guarantee(length == 0, "invalid method ordering length");
3604 }
3605 }
3606
3607 // Verify default methods
3608 if (default_methods() != NULL) {
3609 Array<Method*>* methods = this->default_methods();
3610 for (int j = 0; j < methods->length(); j++) {
3611 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3612 }
3613 for (int j = 0; j < methods->length() - 1; j++) {
3614 Method* m1 = methods->at(j);
3615 Method* m2 = methods->at(j + 1);
3616 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3617 }
3618 }
3619
3620 // Verify JNI static field identifiers
3621 if (jni_ids() != NULL) {
3622 jni_ids()->verify(this);
3623 }
3624
3625 // Verify other fields
3626 if (array_klasses() != NULL) {
3627 guarantee(array_klasses()->is_klass(), "should be klass");
3628 }
3629 if (constants() != NULL) {
3630 guarantee(constants()->is_constantPool(), "should be constant pool");
3631 }
3632 const Klass* anonymous_host = unsafe_anonymous_host();
3633 if (anonymous_host != NULL) {
3634 guarantee(anonymous_host->is_klass(), "should be klass");
3635 }
3636 }
3637
3638 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3639 Klass::oop_verify_on(obj, st);
3640 VerifyFieldClosure blk;
3641 obj->oop_iterate(&blk);
3642 }
3643
3644
3645 // JNIid class for jfieldIDs only
3646 // Note to reviewers:
3647 // These JNI functions are just moved over to column 1 and not changed
3648 // in the compressed oops workspace.
3649 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3650 _holder = holder;
3651 _offset = offset;
3652 _next = next;
3653 debug_only(_is_static_field_id = false;)
3654 }
3655
3656
3657 JNIid* JNIid::find(int offset) {
3658 JNIid* current = this;
3659 while (current != NULL) {
3660 if (current->offset() == offset) return current;
3661 current = current->next();
3662 }
3663 return NULL;
3664 }
3665
3666 void JNIid::deallocate(JNIid* current) {
3667 while (current != NULL) {
3668 JNIid* next = current->next();
3669 delete current;
3670 current = next;
3671 }
3672 }
3673
3674
3675 void JNIid::verify(Klass* holder) {
3676 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3677 int end_field_offset;
3678 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3679
3680 JNIid* current = this;
3681 while (current != NULL) {
3682 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3683 #ifdef ASSERT
3684 int o = current->offset();
3685 if (current->is_static_field_id()) {
3686 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3687 }
3688 #endif
3689 current = current->next();
3690 }
3691 }
3692
3693 #ifdef ASSERT
3694 void InstanceKlass::set_init_state(ClassState state) {
3695 bool good_state = is_shared() ? (_init_state <= state)
3696 : (_init_state < state);
3697 assert(good_state || state == allocated, "illegal state transition");
3698 _init_state = (u1)state;
3699 }
3700 #endif
3701
3702 #if INCLUDE_JVMTI
3703
3704 // RedefineClasses() support for previous versions
3705
3706 // Globally, there is at least one previous version of a class to walk
3707 // during class unloading, which is saved because old methods in the class
3708 // are still running. Otherwise the previous version list is cleaned up.
3709 bool InstanceKlass::_has_previous_versions = false;
3710
3711 // Returns true if there are previous versions of a class for class
3712 // unloading only. Also resets the flag to false. purge_previous_version
3713 // will set the flag to true if there are any left, i.e., if there's any
3714 // work to do for next time. This is to avoid the expensive code cache
3715 // walk in CLDG::clean_deallocate_lists().
3716 bool InstanceKlass::has_previous_versions_and_reset() {
3717 bool ret = _has_previous_versions;
3718 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3719 ret ? "true" : "false");
3720 _has_previous_versions = false;
3721 return ret;
3722 }
3723
3724 // Purge previous versions before adding new previous versions of the class and
3725 // during class unloading.
3726 void InstanceKlass::purge_previous_version_list() {
3727 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3728 assert(has_been_redefined(), "Should only be called for main class");
3729
3730 // Quick exit.
3731 if (previous_versions() == NULL) {
3732 return;
3733 }
3734
3735 // This klass has previous versions so see what we can cleanup
3736 // while it is safe to do so.
3737
3738 int deleted_count = 0; // leave debugging breadcrumbs
3739 int live_count = 0;
3740 ClassLoaderData* loader_data = class_loader_data();
3741 assert(loader_data != NULL, "should never be null");
3742
3743 ResourceMark rm;
3744 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3745
3746 // previous versions are linked together through the InstanceKlass
3747 InstanceKlass* pv_node = previous_versions();
3748 InstanceKlass* last = this;
3749 int version = 0;
3750
3751 // check the previous versions list
3752 for (; pv_node != NULL; ) {
3753
3754 ConstantPool* pvcp = pv_node->constants();
3755 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3756
3757 if (!pvcp->on_stack()) {
3758 // If the constant pool isn't on stack, none of the methods
3759 // are executing. Unlink this previous_version.
3760 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3761 // so will be deallocated during the next phase of class unloading.
3762 log_trace(redefine, class, iklass, purge)
3763 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3764 // For debugging purposes.
3765 pv_node->set_is_scratch_class();
3766 // Unlink from previous version list.
3767 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3768 InstanceKlass* next = pv_node->previous_versions();
3769 pv_node->link_previous_versions(NULL); // point next to NULL
3770 last->link_previous_versions(next);
3771 // Add to the deallocate list after unlinking
3772 loader_data->add_to_deallocate_list(pv_node);
3773 pv_node = next;
3774 deleted_count++;
3775 version++;
3776 continue;
3777 } else {
3778 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3779 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3780 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3781 live_count++;
3782 // found a previous version for next time we do class unloading
3783 _has_previous_versions = true;
3784 }
3785
3786 // At least one method is live in this previous version.
3787 // Reset dead EMCP methods not to get breakpoints.
3788 // All methods are deallocated when all of the methods for this class are no
3789 // longer running.
3790 Array<Method*>* method_refs = pv_node->methods();
3791 if (method_refs != NULL) {
3792 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3793 for (int j = 0; j < method_refs->length(); j++) {
3794 Method* method = method_refs->at(j);
3795
3796 if (!method->on_stack()) {
3797 // no breakpoints for non-running methods
3798 if (method->is_running_emcp()) {
3799 method->set_running_emcp(false);
3800 }
3801 } else {
3802 assert (method->is_obsolete() || method->is_running_emcp(),
3803 "emcp method cannot run after emcp bit is cleared");
3804 log_trace(redefine, class, iklass, purge)
3805 ("purge: %s(%s): prev method @%d in version @%d is alive",
3806 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3807 }
3808 }
3809 }
3810 // next previous version
3811 last = pv_node;
3812 pv_node = pv_node->previous_versions();
3813 version++;
3814 }
3815 log_trace(redefine, class, iklass, purge)
3816 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3817 }
3818
3819 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3820 int emcp_method_count) {
3821 int obsolete_method_count = old_methods->length() - emcp_method_count;
3822
3823 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3824 _previous_versions != NULL) {
3825 // We have a mix of obsolete and EMCP methods so we have to
3826 // clear out any matching EMCP method entries the hard way.
3827 int local_count = 0;
3828 for (int i = 0; i < old_methods->length(); i++) {
3829 Method* old_method = old_methods->at(i);
3830 if (old_method->is_obsolete()) {
3831 // only obsolete methods are interesting
3832 Symbol* m_name = old_method->name();
3833 Symbol* m_signature = old_method->signature();
3834
3835 // previous versions are linked together through the InstanceKlass
3836 int j = 0;
3837 for (InstanceKlass* prev_version = _previous_versions;
3838 prev_version != NULL;
3839 prev_version = prev_version->previous_versions(), j++) {
3840
3841 Array<Method*>* method_refs = prev_version->methods();
3842 for (int k = 0; k < method_refs->length(); k++) {
3843 Method* method = method_refs->at(k);
3844
3845 if (!method->is_obsolete() &&
3846 method->name() == m_name &&
3847 method->signature() == m_signature) {
3848 // The current RedefineClasses() call has made all EMCP
3849 // versions of this method obsolete so mark it as obsolete
3850 log_trace(redefine, class, iklass, add)
3851 ("%s(%s): flush obsolete method @%d in version @%d",
3852 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3853
3854 method->set_is_obsolete();
3855 break;
3856 }
3857 }
3858
3859 // The previous loop may not find a matching EMCP method, but
3860 // that doesn't mean that we can optimize and not go any
3861 // further back in the PreviousVersion generations. The EMCP
3862 // method for this generation could have already been made obsolete,
3863 // but there still may be an older EMCP method that has not
3864 // been made obsolete.
3865 }
3866
3867 if (++local_count >= obsolete_method_count) {
3868 // no more obsolete methods so bail out now
3869 break;
3870 }
3871 }
3872 }
3873 }
3874 }
3875
3876 // Save the scratch_class as the previous version if any of the methods are running.
3877 // The previous_versions are used to set breakpoints in EMCP methods and they are
3878 // also used to clean MethodData links to redefined methods that are no longer running.
3879 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3880 int emcp_method_count) {
3881 assert(Thread::current()->is_VM_thread(),
3882 "only VMThread can add previous versions");
3883
3884 ResourceMark rm;
3885 log_trace(redefine, class, iklass, add)
3886 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3887
3888 // Clean out old previous versions for this class
3889 purge_previous_version_list();
3890
3891 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3892 // a previous redefinition may be made obsolete by this redefinition.
3893 Array<Method*>* old_methods = scratch_class->methods();
3894 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3895
3896 // If the constant pool for this previous version of the class
3897 // is not marked as being on the stack, then none of the methods
3898 // in this previous version of the class are on the stack so
3899 // we don't need to add this as a previous version.
3900 ConstantPool* cp_ref = scratch_class->constants();
3901 if (!cp_ref->on_stack()) {
3902 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3903 // For debugging purposes.
3904 scratch_class->set_is_scratch_class();
3905 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3906 return;
3907 }
3908
3909 if (emcp_method_count != 0) {
3910 // At least one method is still running, check for EMCP methods
3911 for (int i = 0; i < old_methods->length(); i++) {
3912 Method* old_method = old_methods->at(i);
3913 if (!old_method->is_obsolete() && old_method->on_stack()) {
3914 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3915 // we can add breakpoints for it.
3916
3917 // We set the method->on_stack bit during safepoints for class redefinition
3918 // and use this bit to set the is_running_emcp bit.
3919 // After the safepoint, the on_stack bit is cleared and the running emcp
3920 // method may exit. If so, we would set a breakpoint in a method that
3921 // is never reached, but this won't be noticeable to the programmer.
3922 old_method->set_running_emcp(true);
3923 log_trace(redefine, class, iklass, add)
3924 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3925 } else if (!old_method->is_obsolete()) {
3926 log_trace(redefine, class, iklass, add)
3927 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3928 }
3929 }
3930 }
3931
3932 // Add previous version if any methods are still running.
3933 // Set has_previous_version flag for processing during class unloading.
3934 _has_previous_versions = true;
3935 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3936 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3937 scratch_class->link_previous_versions(previous_versions());
3938 link_previous_versions(scratch_class);
3939 } // end add_previous_version()
3940
3941 #endif // INCLUDE_JVMTI
3942
3943 Method* InstanceKlass::method_with_idnum(int idnum) {
3944 Method* m = NULL;
3945 if (idnum < methods()->length()) {
3946 m = methods()->at(idnum);
3947 }
3948 if (m == NULL || m->method_idnum() != idnum) {
3949 for (int index = 0; index < methods()->length(); ++index) {
3950 m = methods()->at(index);
3951 if (m->method_idnum() == idnum) {
3952 return m;
3953 }
3954 }
3955 // None found, return null for the caller to handle.
3956 return NULL;
3957 }
3958 return m;
3959 }
3960
3961
3962 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3963 if (idnum >= methods()->length()) {
3964 return NULL;
3965 }
3966 Method* m = methods()->at(idnum);
3967 if (m != NULL && m->orig_method_idnum() == idnum) {
3968 return m;
3969 }
3970 // Obsolete method idnum does not match the original idnum
3971 for (int index = 0; index < methods()->length(); ++index) {
3972 m = methods()->at(index);
3973 if (m->orig_method_idnum() == idnum) {
3974 return m;
3975 }
3976 }
3977 // None found, return null for the caller to handle.
3978 return NULL;
3979 }
3980
3981
3982 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3983 InstanceKlass* holder = get_klass_version(version);
3984 if (holder == NULL) {
3985 return NULL; // The version of klass is gone, no method is found
3986 }
3987 Method* method = holder->method_with_orig_idnum(idnum);
3988 return method;
3989 }
3990
3991 #if INCLUDE_JVMTI
3992 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3993 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3994 // Ignore the archived class stream data
3995 return NULL;
3996 } else {
3997 return _cached_class_file;
3998 }
3999 }
4000
4001 jint InstanceKlass::get_cached_class_file_len() {
4002 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4003 }
4004
4005 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4006 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4007 }
4008
4009 #if INCLUDE_CDS
4010 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
4011 if (DumpSharedSpaces) {
4012 return _cached_class_file;
4013 } else {
4014 assert(this->is_shared(), "class should be shared");
4015 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
4016 return _cached_class_file;
4017 } else {
4018 return NULL;
4019 }
4020 }
4021 }
4022 #endif
4023 #endif