1 /*
2 * Copyright (c) 1997, 2012, 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 "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/metadataFactory.hpp"
38 #include "memory/oopFactory.hpp"
39 #include "oops/fieldStreams.hpp"
40 #include "oops/instanceClassLoaderKlass.hpp"
41 #include "oops/instanceKlass.hpp"
42 #include "oops/instanceMirrorKlass.hpp"
43 #include "oops/instanceOop.hpp"
44 #include "oops/klass.inline.hpp"
45 #include "oops/method.hpp"
46 #include "oops/oop.inline.hpp"
47 #include "oops/symbol.hpp"
48 #include "prims/jvmtiExport.hpp"
49 #include "prims/jvmtiRedefineClassesTrace.hpp"
50 #include "runtime/fieldDescriptor.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "services/threadService.hpp"
55 #include "utilities/dtrace.hpp"
56 #ifdef TARGET_OS_FAMILY_linux
57 # include "thread_linux.inline.hpp"
58 #endif
59 #ifdef TARGET_OS_FAMILY_solaris
60 # include "thread_solaris.inline.hpp"
61 #endif
62 #ifdef TARGET_OS_FAMILY_windows
63 # include "thread_windows.inline.hpp"
64 #endif
65 #ifdef TARGET_OS_FAMILY_bsd
66 # include "thread_bsd.inline.hpp"
67 #endif
68 #ifndef SERIALGC
69 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
70 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
71 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
72 #include "gc_implementation/g1/g1RemSet.inline.hpp"
73 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
74 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
75 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
76 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
77 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
78 #include "oops/oop.pcgc.inline.hpp"
79 #endif
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86 #ifndef USDT2
87
88 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
89 char*, intptr_t, oop, intptr_t);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
95 char*, intptr_t, oop, intptr_t, int);
96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
97 char*, intptr_t, oop, intptr_t, int);
98 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
99 char*, intptr_t, oop, intptr_t, int);
100 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
101 char*, intptr_t, oop, intptr_t, int);
102 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
103 char*, intptr_t, oop, intptr_t, int);
104
105 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
106 { \
107 char* data = NULL; \
108 int len = 0; \
109 Symbol* name = (clss)->name(); \
110 if (name != NULL) { \
111 data = (char*)name->bytes(); \
112 len = name->utf8_length(); \
113 } \
114 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
115 data, len, (clss)->class_loader(), thread_type); \
116 }
117
118 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
119 { \
120 char* data = NULL; \
121 int len = 0; \
122 Symbol* name = (clss)->name(); \
123 if (name != NULL) { \
124 data = (char*)name->bytes(); \
125 len = name->utf8_length(); \
126 } \
127 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
128 data, len, (clss)->class_loader(), thread_type, wait); \
129 }
130 #else /* USDT2 */
131
132 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
133 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
134 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
135 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
136 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
137 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
138 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
139 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
140 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
141 { \
142 char* data = NULL; \
143 int len = 0; \
144 Symbol* name = (clss)->name(); \
145 if (name != NULL) { \
146 data = (char*)name->bytes(); \
147 len = name->utf8_length(); \
148 } \
149 HOTSPOT_CLASS_INITIALIZATION_##type( \
150 data, len, (clss)->class_loader(), thread_type); \
151 }
152
153 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
154 { \
155 char* data = NULL; \
156 int len = 0; \
157 Symbol* name = (clss)->name(); \
158 if (name != NULL) { \
159 data = (char*)name->bytes(); \
160 len = name->utf8_length(); \
161 } \
162 HOTSPOT_CLASS_INITIALIZATION_##type( \
163 data, len, (clss)->class_loader(), thread_type, wait); \
164 }
165 #endif /* USDT2 */
166
167 #else // ndef DTRACE_ENABLED
168
169 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
170 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
171
172 #endif // ndef DTRACE_ENABLED
173
174 Klass* InstanceKlass::allocate_instance_klass(ClassLoaderData* loader_data,
175 int vtable_len,
176 int itable_len,
177 int static_field_size,
178 int nonstatic_oop_map_size,
179 ReferenceType rt,
180 AccessFlags access_flags,
181 Symbol* name,
182 Klass* super_klass,
183 KlassHandle host_klass,
184 TRAPS) {
185
186 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
187 access_flags.is_interface(),
188 !host_klass.is_null());
189
190 // Allocation
191 InstanceKlass* ik;
192 if (rt == REF_NONE) {
193 if (name == vmSymbols::java_lang_Class()) {
194 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
195 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
196 access_flags, !host_klass.is_null());
197 } else if (name == vmSymbols::java_lang_ClassLoader() ||
198 (SystemDictionary::ClassLoader_klass_loaded() &&
199 super_klass != NULL &&
200 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
201 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
202 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
203 access_flags, !host_klass.is_null());
204 } else {
205 // normal class
206 ik = new (loader_data, size, THREAD) InstanceKlass(
207 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
208 access_flags, !host_klass.is_null());
209 }
210 } else {
211 // reference klass
212 ik = new (loader_data, size, THREAD) InstanceRefKlass(
213 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
214 access_flags, !host_klass.is_null());
215 }
216
217 return ik;
218 }
219
220 InstanceKlass::InstanceKlass(int vtable_len,
221 int itable_len,
222 int static_field_size,
223 int nonstatic_oop_map_size,
224 ReferenceType rt,
225 AccessFlags access_flags,
226 bool is_anonymous) {
227 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
228
229 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
230 access_flags.is_interface(), is_anonymous);
231
232 // The sizes of these these three variables are used for determining the
233 // size of the instanceKlassOop. It is critical that these are set to the right
234 // sizes before the first GC, i.e., when we allocate the mirror.
235 this->set_vtable_length(vtable_len);
236 this->set_itable_length(itable_len);
237 this->set_static_field_size(static_field_size);
238 this->set_nonstatic_oop_map_size(nonstatic_oop_map_size);
239 this->set_access_flags(access_flags);
240 this->set_is_anonymous(is_anonymous);
241 assert(this->size() == size, "wrong size for object");
242
243 this->set_array_klasses(NULL);
244 this->set_methods(NULL);
245 this->set_method_ordering(NULL);
246 this->set_local_interfaces(NULL);
247 this->set_transitive_interfaces(NULL);
248 this->init_implementor();
249 this->set_fields(NULL, 0);
250 this->set_constants(NULL);
251 this->set_class_loader_data(NULL);
252 this->set_protection_domain(NULL);
253 this->set_signers(NULL);
254 this->set_source_file_name(NULL);
255 this->set_source_debug_extension(NULL, 0);
256 this->set_array_name(NULL);
257 this->set_inner_classes(NULL);
258 this->set_static_oop_field_count(0);
259 this->set_nonstatic_field_size(0);
260 this->set_is_marked_dependent(false);
261 this->set_init_state(InstanceKlass::allocated);
262 this->set_init_thread(NULL);
263 this->set_init_lock(NULL);
264 this->set_reference_type(rt);
265 this->set_oop_map_cache(NULL);
266 this->set_jni_ids(NULL);
267 this->set_osr_nmethods_head(NULL);
268 this->set_breakpoints(NULL);
269 this->init_previous_versions();
270 this->set_generic_signature(NULL);
271 this->release_set_methods_jmethod_ids(NULL);
272 this->release_set_methods_cached_itable_indices(NULL);
273 this->set_annotations(NULL);
274 this->set_jvmti_cached_class_field_map(NULL);
275 this->set_initial_method_idnum(0);
276
277 // initialize the non-header words to zero
278 intptr_t* p = (intptr_t*)this;
279 for (int index = InstanceKlass::header_size(); index < size; index++) {
280 p[index] = NULL_WORD;
281 }
282
283 // Set temporary value until parseClassFile updates it with the real instance
284 // size.
285 this->set_layout_helper(Klass::instance_layout_helper(0, true));
286 }
287
288
289 // This function deallocates the metadata and C heap pointers that the
290 // InstanceKlass points to.
291 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
292
293 // Orphan the mirror first, CMS thinks it's still live.
294 java_lang_Class::set_klass(java_mirror(), NULL);
295
296 // Need to take this class off the class loader data list.
297 loader_data->remove_class(this);
298
299 // The array_klass for this class is created later, after error handling.
300 // For class redefinition, we keep the original class so this scratch class
301 // doesn't have an array class. Either way, assert that there is nothing
302 // to deallocate.
303 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
304
305 // Release C heap allocated data that this might point to, which includes
306 // reference counting symbol names.
307 release_C_heap_structures();
308
309 Array<Method*>* ms = methods();
310 if (ms != Universe::the_empty_method_array()) {
311 for (int i = 0; i <= methods()->length() -1 ; i++) {
312 Method* method = methods()->at(i);
313 // Only want to delete methods that are not executing for RedefineClasses.
314 // The previous version will point to them so they're not totally dangling
315 assert (!method->on_stack(), "shouldn't be called with methods on stack");
316 MetadataFactory::free_metadata(loader_data, method);
317 }
318 MetadataFactory::free_array<Method*>(loader_data, methods());
319 }
320 set_methods(NULL);
321
322 if (method_ordering() != Universe::the_empty_int_array()) {
323 MetadataFactory::free_array<int>(loader_data, method_ordering());
324 }
325 set_method_ordering(NULL);
326
327 // This array is in Klass, but remove it with the InstanceKlass since
328 // this place would be the only caller and it can share memory with transitive
329 // interfaces.
330 if (secondary_supers() != Universe::the_empty_klass_array() &&
331 secondary_supers() != transitive_interfaces()) {
332 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
333 }
334 set_secondary_supers(NULL);
335
336 // Only deallocate transitive interfaces if not empty, same as super class
337 // or same as local interfaces. See code in parseClassFile.
338 Array<Klass*>* ti = transitive_interfaces();
339 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces()) {
340 // check that the interfaces don't come from super class
341 Array<Klass*>* sti = (super() == NULL) ? NULL :
342 InstanceKlass::cast(super())->transitive_interfaces();
343 if (ti != sti) {
344 MetadataFactory::free_array<Klass*>(loader_data, ti);
345 }
346 }
347 set_transitive_interfaces(NULL);
348
349 // local interfaces can be empty
350 Array<Klass*>* li = local_interfaces();
351 if (li != Universe::the_empty_klass_array()) {
352 MetadataFactory::free_array<Klass*>(loader_data, li);
353 }
354 set_local_interfaces(NULL);
355
356 MetadataFactory::free_array<jushort>(loader_data, fields());
357 set_fields(NULL, 0);
358
359 // If a method from a redefined class is using this constant pool, don't
360 // delete it, yet. The new class's previous version will point to this.
361 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
362 MetadataFactory::free_metadata(loader_data, constants());
363 set_constants(NULL);
364
365 if (inner_classes() != Universe::the_empty_short_array()) {
366 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
367 }
368 set_inner_classes(NULL);
369
370 // Null out Java heap objects, although these won't be walked to keep
371 // alive once this InstanceKlass is deallocated.
372 set_protection_domain(NULL);
373 set_signers(NULL);
374 set_init_lock(NULL);
375 set_annotations(NULL);
376 }
377
378 volatile oop InstanceKlass::init_lock() const {
379 volatile oop lock = _init_lock; // read once
380 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
381 "only fully initialized state can have a null lock");
382 return lock;
383 }
384
385 // Set the initialization lock to null so the object can be GC'ed. Any racing
386 // threads to get this lock will see a null lock and will not lock.
387 // That's okay because they all check for initialized state after getting
388 // the lock and return.
389 void InstanceKlass::fence_and_clear_init_lock() {
390 // make sure previous stores are all done, notably the init_state.
391 OrderAccess::storestore();
392 klass_oop_store(&_init_lock, NULL);
393 assert(!is_not_initialized(), "class must be initialized now");
394 }
395
396
397 bool InstanceKlass::should_be_initialized() const {
398 return !is_initialized();
399 }
400
401 klassVtable* InstanceKlass::vtable() const {
402 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
403 }
404
405 klassItable* InstanceKlass::itable() const {
406 return new klassItable(instanceKlassHandle(this));
407 }
408
409 void InstanceKlass::eager_initialize(Thread *thread) {
410 if (!EagerInitialization) return;
411
412 if (this->is_not_initialized()) {
413 // abort if the the class has a class initializer
414 if (this->class_initializer() != NULL) return;
415
416 // abort if it is java.lang.Object (initialization is handled in genesis)
417 Klass* super = this->super();
418 if (super == NULL) return;
419
420 // abort if the super class should be initialized
421 if (!InstanceKlass::cast(super)->is_initialized()) return;
422
423 // call body to expose the this pointer
424 instanceKlassHandle this_oop(thread, this);
425 eager_initialize_impl(this_oop);
426 }
427 }
428
429
430 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
431 EXCEPTION_MARK;
432 volatile oop init_lock = this_oop->init_lock();
433 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
434
435 // abort if someone beat us to the initialization
436 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
437
438 ClassState old_state = this_oop->init_state();
439 link_class_impl(this_oop, true, THREAD);
440 if (HAS_PENDING_EXCEPTION) {
441 CLEAR_PENDING_EXCEPTION;
442 // Abort if linking the class throws an exception.
443
444 // Use a test to avoid redundantly resetting the state if there's
445 // no change. Set_init_state() asserts that state changes make
446 // progress, whereas here we might just be spinning in place.
447 if( old_state != this_oop->_init_state )
448 this_oop->set_init_state (old_state);
449 } else {
450 // linking successfull, mark class as initialized
451 this_oop->set_init_state (fully_initialized);
452 this_oop->fence_and_clear_init_lock();
453 // trace
454 if (TraceClassInitialization) {
455 ResourceMark rm(THREAD);
456 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
457 }
458 }
459 }
460
461
462 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
463 // process. The step comments refers to the procedure described in that section.
464 // Note: implementation moved to static method to expose the this pointer.
465 void InstanceKlass::initialize(TRAPS) {
466 if (this->should_be_initialized()) {
467 HandleMark hm(THREAD);
468 instanceKlassHandle this_oop(THREAD, this);
469 initialize_impl(this_oop, CHECK);
470 // Note: at this point the class may be initialized
471 // OR it may be in the state of being initialized
472 // in case of recursive initialization!
473 } else {
474 assert(is_initialized(), "sanity check");
475 }
476 }
477
478
479 bool InstanceKlass::verify_code(
480 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
481 // 1) Verify the bytecodes
482 Verifier::Mode mode =
483 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
484 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
485 }
486
487
488 // Used exclusively by the shared spaces dump mechanism to prevent
489 // classes mapped into the shared regions in new VMs from appearing linked.
490
491 void InstanceKlass::unlink_class() {
492 assert(is_linked(), "must be linked");
493 _init_state = loaded;
494 }
495
496 void InstanceKlass::link_class(TRAPS) {
497 assert(is_loaded(), "must be loaded");
498 if (!is_linked()) {
499 HandleMark hm(THREAD);
500 instanceKlassHandle this_oop(THREAD, this);
501 link_class_impl(this_oop, true, CHECK);
502 }
503 }
504
505 // Called to verify that a class can link during initialization, without
506 // throwing a VerifyError.
507 bool InstanceKlass::link_class_or_fail(TRAPS) {
508 assert(is_loaded(), "must be loaded");
509 if (!is_linked()) {
510 HandleMark hm(THREAD);
511 instanceKlassHandle this_oop(THREAD, this);
512 link_class_impl(this_oop, false, CHECK_false);
513 }
514 return is_linked();
515 }
516
517 bool InstanceKlass::link_class_impl(
518 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
519 // check for error state
520 if (this_oop->is_in_error_state()) {
521 ResourceMark rm(THREAD);
522 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
523 this_oop->external_name(), false);
524 }
525 // return if already verified
526 if (this_oop->is_linked()) {
527 return true;
528 }
529
530 // Timing
531 // timer handles recursion
532 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
533 JavaThread* jt = (JavaThread*)THREAD;
534
535 // link super class before linking this class
536 instanceKlassHandle super(THREAD, this_oop->super());
537 if (super.not_null()) {
538 if (super->is_interface()) { // check if super class is an interface
539 ResourceMark rm(THREAD);
540 Exceptions::fthrow(
541 THREAD_AND_LOCATION,
542 vmSymbols::java_lang_IncompatibleClassChangeError(),
543 "class %s has interface %s as super class",
544 this_oop->external_name(),
545 super->external_name()
546 );
547 return false;
548 }
549
550 link_class_impl(super, throw_verifyerror, CHECK_false);
551 }
552
553 // link all interfaces implemented by this class before linking this class
554 Array<Klass*>* interfaces = this_oop->local_interfaces();
555 int num_interfaces = interfaces->length();
556 for (int index = 0; index < num_interfaces; index++) {
557 HandleMark hm(THREAD);
558 instanceKlassHandle ih(THREAD, interfaces->at(index));
559 link_class_impl(ih, throw_verifyerror, CHECK_false);
560 }
561
562 // in case the class is linked in the process of linking its superclasses
563 if (this_oop->is_linked()) {
564 return true;
565 }
566
567 // trace only the link time for this klass that includes
568 // the verification time
569 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
570 ClassLoader::perf_class_link_selftime(),
571 ClassLoader::perf_classes_linked(),
572 jt->get_thread_stat()->perf_recursion_counts_addr(),
573 jt->get_thread_stat()->perf_timers_addr(),
574 PerfClassTraceTime::CLASS_LINK);
575
576 // verification & rewriting
577 {
578 volatile oop init_lock = this_oop->init_lock();
579 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
580 // rewritten will have been set if loader constraint error found
581 // on an earlier link attempt
582 // don't verify or rewrite if already rewritten
583
584 if (!this_oop->is_linked()) {
585 if (!this_oop->is_rewritten()) {
586 {
587 // Timer includes any side effects of class verification (resolution,
588 // etc), but not recursive entry into verify_code().
589 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
590 ClassLoader::perf_class_verify_selftime(),
591 ClassLoader::perf_classes_verified(),
592 jt->get_thread_stat()->perf_recursion_counts_addr(),
593 jt->get_thread_stat()->perf_timers_addr(),
594 PerfClassTraceTime::CLASS_VERIFY);
595 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
596 if (!verify_ok) {
597 return false;
598 }
599 }
600
601 // Just in case a side-effect of verify linked this class already
602 // (which can sometimes happen since the verifier loads classes
603 // using custom class loaders, which are free to initialize things)
604 if (this_oop->is_linked()) {
605 return true;
606 }
607
608 // also sets rewritten
609 this_oop->rewrite_class(CHECK_false);
610 }
611
612 // relocate jsrs and link methods after they are all rewritten
613 this_oop->relocate_and_link_methods(CHECK_false);
614
615 // Initialize the vtable and interface table after
616 // methods have been rewritten since rewrite may
617 // fabricate new Method*s.
618 // also does loader constraint checking
619 if (!this_oop()->is_shared()) {
620 ResourceMark rm(THREAD);
621 this_oop->vtable()->initialize_vtable(true, CHECK_false);
622 this_oop->itable()->initialize_itable(true, CHECK_false);
623 }
624 #ifdef ASSERT
625 else {
626 ResourceMark rm(THREAD);
627 this_oop->vtable()->verify(tty, true);
628 // In case itable verification is ever added.
629 // this_oop->itable()->verify(tty, true);
630 }
631 #endif
632 this_oop->set_init_state(linked);
633 if (JvmtiExport::should_post_class_prepare()) {
634 Thread *thread = THREAD;
635 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
636 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
637 }
638 }
639 }
640 return true;
641 }
642
643
644 // Rewrite the byte codes of all of the methods of a class.
645 // The rewriter must be called exactly once. Rewriting must happen after
646 // verification but before the first method of the class is executed.
647 void InstanceKlass::rewrite_class(TRAPS) {
648 assert(is_loaded(), "must be loaded");
649 instanceKlassHandle this_oop(THREAD, this);
650 if (this_oop->is_rewritten()) {
651 assert(this_oop()->is_shared(), "rewriting an unshared class?");
652 return;
653 }
654 Rewriter::rewrite(this_oop, CHECK);
655 this_oop->set_rewritten();
656 }
657
658 // Now relocate and link method entry points after class is rewritten.
659 // This is outside is_rewritten flag. In case of an exception, it can be
660 // executed more than once.
661 void InstanceKlass::relocate_and_link_methods(TRAPS) {
662 assert(is_loaded(), "must be loaded");
663 instanceKlassHandle this_oop(THREAD, this);
664 Rewriter::relocate_and_link(this_oop, CHECK);
665 }
666
667
668 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
669 // Make sure klass is linked (verified) before initialization
670 // A class could already be verified, since it has been reflected upon.
671 this_oop->link_class(CHECK);
672
673 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
674
675 bool wait = false;
676
677 // refer to the JVM book page 47 for description of steps
678 // Step 1
679 {
680 volatile oop init_lock = this_oop->init_lock();
681 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
682
683 Thread *self = THREAD; // it's passed the current thread
684
685 // Step 2
686 // If we were to use wait() instead of waitInterruptibly() then
687 // we might end up throwing IE from link/symbol resolution sites
688 // that aren't expected to throw. This would wreak havoc. See 6320309.
689 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
690 wait = true;
691 ol.waitUninterruptibly(CHECK);
692 }
693
694 // Step 3
695 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
696 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
697 return;
698 }
699
700 // Step 4
701 if (this_oop->is_initialized()) {
702 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
703 return;
704 }
705
706 // Step 5
707 if (this_oop->is_in_error_state()) {
708 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
709 ResourceMark rm(THREAD);
710 const char* desc = "Could not initialize class ";
711 const char* className = this_oop->external_name();
712 size_t msglen = strlen(desc) + strlen(className) + 1;
713 char* message = NEW_RESOURCE_ARRAY(char, msglen);
714 if (NULL == message) {
715 // Out of memory: can't create detailed error message
716 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
717 } else {
718 jio_snprintf(message, msglen, "%s%s", desc, className);
719 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
720 }
721 }
722
723 // Step 6
724 this_oop->set_init_state(being_initialized);
725 this_oop->set_init_thread(self);
726 }
727
728 // Step 7
729 Klass* super_klass = this_oop->super();
730 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
731 super_klass->initialize(THREAD);
732
733 if (HAS_PENDING_EXCEPTION) {
734 Handle e(THREAD, PENDING_EXCEPTION);
735 CLEAR_PENDING_EXCEPTION;
736 {
737 EXCEPTION_MARK;
738 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
739 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
740 }
741 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
742 THROW_OOP(e());
743 }
744 }
745
746 if (this_oop->has_default_methods()) {
747 // Step 7.5: initialize any interfaces which have default methods
748 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
749 Klass* iface = this_oop->local_interfaces()->at(i);
750 InstanceKlass* ik = InstanceKlass::cast(iface);
751 if (ik->has_default_methods() && ik->should_be_initialized()) {
752 ik->initialize(THREAD);
753
754 if (HAS_PENDING_EXCEPTION) {
755 Handle e(THREAD, PENDING_EXCEPTION);
756 CLEAR_PENDING_EXCEPTION;
757 {
758 EXCEPTION_MARK;
759 // Locks object, set state, and notify all waiting threads
760 this_oop->set_initialization_state_and_notify(
761 initialization_error, THREAD);
762
763 // ignore any exception thrown, superclass initialization error is
764 // thrown below
765 CLEAR_PENDING_EXCEPTION;
766 }
767 DTRACE_CLASSINIT_PROBE_WAIT(
768 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
769 THROW_OOP(e());
770 }
771 }
772 }
773 }
774
775 // Step 8
776 {
777 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
778 JavaThread* jt = (JavaThread*)THREAD;
779 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
780 // Timer includes any side effects of class initialization (resolution,
781 // etc), but not recursive entry into call_class_initializer().
782 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
783 ClassLoader::perf_class_init_selftime(),
784 ClassLoader::perf_classes_inited(),
785 jt->get_thread_stat()->perf_recursion_counts_addr(),
786 jt->get_thread_stat()->perf_timers_addr(),
787 PerfClassTraceTime::CLASS_CLINIT);
788 this_oop->call_class_initializer(THREAD);
789 }
790
791 // Step 9
792 if (!HAS_PENDING_EXCEPTION) {
793 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
794 { ResourceMark rm(THREAD);
795 debug_only(this_oop->vtable()->verify(tty, true);)
796 }
797 }
798 else {
799 // Step 10 and 11
800 Handle e(THREAD, PENDING_EXCEPTION);
801 CLEAR_PENDING_EXCEPTION;
802 {
803 EXCEPTION_MARK;
804 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
805 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
806 }
807 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
808 if (e->is_a(SystemDictionary::Error_klass())) {
809 THROW_OOP(e());
810 } else {
811 JavaCallArguments args(e);
812 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
813 vmSymbols::throwable_void_signature(),
814 &args);
815 }
816 }
817 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
818 }
819
820
821 // Note: implementation moved to static method to expose the this pointer.
822 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
823 instanceKlassHandle kh(THREAD, this);
824 set_initialization_state_and_notify_impl(kh, state, CHECK);
825 }
826
827 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
828 volatile oop init_lock = this_oop->init_lock();
829 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
830 this_oop->set_init_state(state);
831 this_oop->fence_and_clear_init_lock();
832 ol.notify_all(CHECK);
833 }
834
835 // The embedded _implementor field can only record one implementor.
836 // When there are more than one implementors, the _implementor field
837 // is set to the interface Klass* itself. Following are the possible
838 // values for the _implementor field:
839 // NULL - no implementor
840 // implementor Klass* - one implementor
841 // self - more than one implementor
842 //
843 // The _implementor field only exists for interfaces.
844 void InstanceKlass::add_implementor(Klass* k) {
845 assert(Compile_lock->owned_by_self(), "");
846 assert(is_interface(), "not interface");
847 // Filter out my subinterfaces.
848 // (Note: Interfaces are never on the subklass list.)
849 if (InstanceKlass::cast(k)->is_interface()) return;
850
851 // Filter out subclasses whose supers already implement me.
852 // (Note: CHA must walk subclasses of direct implementors
853 // in order to locate indirect implementors.)
854 Klass* sk = InstanceKlass::cast(k)->super();
855 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
856 // We only need to check one immediate superclass, since the
857 // implements_interface query looks at transitive_interfaces.
858 // Any supers of the super have the same (or fewer) transitive_interfaces.
859 return;
860
861 Klass* ik = implementor();
862 if (ik == NULL) {
863 set_implementor(k);
864 } else if (ik != this) {
865 // There is already an implementor. Use itself as an indicator of
866 // more than one implementors.
867 set_implementor(this);
868 }
869
870 // The implementor also implements the transitive_interfaces
871 for (int index = 0; index < local_interfaces()->length(); index++) {
872 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
873 }
874 }
875
876 void InstanceKlass::init_implementor() {
877 if (is_interface()) {
878 set_implementor(NULL);
879 }
880 }
881
882
883 void InstanceKlass::process_interfaces(Thread *thread) {
884 // link this class into the implementors list of every interface it implements
885 Klass* this_as_klass_oop = this;
886 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
887 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
888 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
889 assert(interf->is_interface(), "expected interface");
890 interf->add_implementor(this_as_klass_oop);
891 }
892 }
893
894 bool InstanceKlass::can_be_primary_super_slow() const {
895 if (is_interface())
896 return false;
897 else
898 return Klass::can_be_primary_super_slow();
899 }
900
901 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
902 // The secondaries are the implemented interfaces.
903 InstanceKlass* ik = InstanceKlass::cast(this);
904 Array<Klass*>* interfaces = ik->transitive_interfaces();
905 int num_secondaries = num_extra_slots + interfaces->length();
906 if (num_secondaries == 0) {
907 // Must share this for correct bootstrapping!
908 set_secondary_supers(Universe::the_empty_klass_array());
909 return NULL;
910 } else if (num_extra_slots == 0) {
911 // The secondary super list is exactly the same as the transitive interfaces.
912 // Redefine classes has to be careful not to delete this!
913 set_secondary_supers(interfaces);
914 return NULL;
915 } else {
916 // Copy transitive interfaces to a temporary growable array to be constructed
917 // into the secondary super list with extra slots.
918 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
919 for (int i = 0; i < interfaces->length(); i++) {
920 secondaries->push(interfaces->at(i));
921 }
922 return secondaries;
923 }
924 }
925
926 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
927 if (k->is_interface()) {
928 return implements_interface(k);
929 } else {
930 return Klass::compute_is_subtype_of(k);
931 }
932 }
933
934 bool InstanceKlass::implements_interface(Klass* k) const {
935 if (this == k) return true;
936 assert(k->is_interface(), "should be an interface class");
937 for (int i = 0; i < transitive_interfaces()->length(); i++) {
938 if (transitive_interfaces()->at(i) == k) {
939 return true;
940 }
941 }
942 return false;
943 }
944
945 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
946 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
947 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
948 report_java_out_of_memory("Requested array size exceeds VM limit");
949 JvmtiExport::post_array_size_exhausted();
950 THROW_OOP_0(Universe::out_of_memory_error_array_size());
951 }
952 int size = objArrayOopDesc::object_size(length);
953 Klass* ak = array_klass(n, CHECK_NULL);
954 KlassHandle h_ak (THREAD, ak);
955 objArrayOop o =
956 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
957 return o;
958 }
959
960 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
961 if (TraceFinalizerRegistration) {
962 tty->print("Registered ");
963 i->print_value_on(tty);
964 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
965 }
966 instanceHandle h_i(THREAD, i);
967 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
968 JavaValue result(T_VOID);
969 JavaCallArguments args(h_i);
970 methodHandle mh (THREAD, Universe::finalizer_register_method());
971 JavaCalls::call(&result, mh, &args, CHECK_NULL);
972 return h_i();
973 }
974
975 instanceOop InstanceKlass::allocate_instance(TRAPS) {
976 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
977 int size = size_helper(); // Query before forming handle.
978
979 KlassHandle h_k(THREAD, this);
980
981 instanceOop i;
982
983 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
984 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
985 i = register_finalizer(i, CHECK_NULL);
986 }
987 return i;
988 }
989
990 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
991 if (is_interface() || is_abstract()) {
992 ResourceMark rm(THREAD);
993 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
994 : vmSymbols::java_lang_InstantiationException(), external_name());
995 }
996 if (this == SystemDictionary::Class_klass()) {
997 ResourceMark rm(THREAD);
998 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
999 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1000 }
1001 }
1002
1003 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1004 instanceKlassHandle this_oop(THREAD, this);
1005 return array_klass_impl(this_oop, or_null, n, THREAD);
1006 }
1007
1008 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1009 if (this_oop->array_klasses() == NULL) {
1010 if (or_null) return NULL;
1011
1012 ResourceMark rm;
1013 JavaThread *jt = (JavaThread *)THREAD;
1014 {
1015 // Atomic creation of array_klasses
1016 MutexLocker mc(Compile_lock, THREAD); // for vtables
1017 MutexLocker ma(MultiArray_lock, THREAD);
1018
1019 // Check if update has already taken place
1020 if (this_oop->array_klasses() == NULL) {
1021 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1022 this_oop->set_array_klasses(k);
1023 }
1024 }
1025 }
1026 // _this will always be set at this point
1027 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1028 if (or_null) {
1029 return oak->array_klass_or_null(n);
1030 }
1031 return oak->array_klass(n, CHECK_NULL);
1032 }
1033
1034 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1035 return array_klass_impl(or_null, 1, THREAD);
1036 }
1037
1038 void InstanceKlass::call_class_initializer(TRAPS) {
1039 instanceKlassHandle ik (THREAD, this);
1040 call_class_initializer_impl(ik, THREAD);
1041 }
1042
1043 static int call_class_initializer_impl_counter = 0; // for debugging
1044
1045 Method* InstanceKlass::class_initializer() {
1046 Method* clinit = find_method(
1047 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1048 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1049 return clinit;
1050 }
1051 return NULL;
1052 }
1053
1054 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1055 if (ReplayCompiles &&
1056 (ReplaySuppressInitializers == 1 ||
1057 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1058 // Hide the existence of the initializer for the purpose of replaying the compile
1059 return;
1060 }
1061
1062 methodHandle h_method(THREAD, this_oop->class_initializer());
1063 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1064 if (TraceClassInitialization) {
1065 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1066 this_oop->name()->print_value();
1067 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1068 }
1069 if (h_method() != NULL) {
1070 JavaCallArguments args; // No arguments
1071 JavaValue result(T_VOID);
1072 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1073 }
1074 }
1075
1076
1077 void InstanceKlass::mask_for(methodHandle method, int bci,
1078 InterpreterOopMap* entry_for) {
1079 // Dirty read, then double-check under a lock.
1080 if (_oop_map_cache == NULL) {
1081 // Otherwise, allocate a new one.
1082 MutexLocker x(OopMapCacheAlloc_lock);
1083 // First time use. Allocate a cache in C heap
1084 if (_oop_map_cache == NULL) {
1085 _oop_map_cache = new OopMapCache();
1086 }
1087 }
1088 // _oop_map_cache is constant after init; lookup below does is own locking.
1089 _oop_map_cache->lookup(method, bci, entry_for);
1090 }
1091
1092
1093 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1094 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1095 Symbol* f_name = fs.name();
1096 Symbol* f_sig = fs.signature();
1097 if (f_name == name && f_sig == sig) {
1098 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1099 return true;
1100 }
1101 }
1102 return false;
1103 }
1104
1105
1106 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1107 const int n = local_interfaces()->length();
1108 for (int i = 0; i < n; i++) {
1109 Klass* intf1 = local_interfaces()->at(i);
1110 assert(intf1->is_interface(), "just checking type");
1111 // search for field in current interface
1112 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1113 assert(fd->is_static(), "interface field must be static");
1114 return intf1;
1115 }
1116 // search for field in direct superinterfaces
1117 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1118 if (intf2 != NULL) return intf2;
1119 }
1120 // otherwise field lookup fails
1121 return NULL;
1122 }
1123
1124
1125 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1126 // search order according to newest JVM spec (5.4.3.2, p.167).
1127 // 1) search for field in current klass
1128 if (find_local_field(name, sig, fd)) {
1129 return const_cast<InstanceKlass*>(this);
1130 }
1131 // 2) search for field recursively in direct superinterfaces
1132 { Klass* intf = find_interface_field(name, sig, fd);
1133 if (intf != NULL) return intf;
1134 }
1135 // 3) apply field lookup recursively if superclass exists
1136 { Klass* supr = super();
1137 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1138 }
1139 // 4) otherwise field lookup fails
1140 return NULL;
1141 }
1142
1143
1144 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1145 // search order according to newest JVM spec (5.4.3.2, p.167).
1146 // 1) search for field in current klass
1147 if (find_local_field(name, sig, fd)) {
1148 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1149 }
1150 // 2) search for field recursively in direct superinterfaces
1151 if (is_static) {
1152 Klass* intf = find_interface_field(name, sig, fd);
1153 if (intf != NULL) return intf;
1154 }
1155 // 3) apply field lookup recursively if superclass exists
1156 { Klass* supr = super();
1157 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1158 }
1159 // 4) otherwise field lookup fails
1160 return NULL;
1161 }
1162
1163
1164 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1165 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1166 if (fs.offset() == offset) {
1167 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1168 if (fd->is_static() == is_static) return true;
1169 }
1170 }
1171 return false;
1172 }
1173
1174
1175 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1176 Klass* klass = const_cast<InstanceKlass*>(this);
1177 while (klass != NULL) {
1178 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1179 return true;
1180 }
1181 klass = klass->super();
1182 }
1183 return false;
1184 }
1185
1186
1187 void InstanceKlass::methods_do(void f(Method* method)) {
1188 int len = methods()->length();
1189 for (int index = 0; index < len; index++) {
1190 Method* m = methods()->at(index);
1191 assert(m->is_method(), "must be method");
1192 f(m);
1193 }
1194 }
1195
1196
1197 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1198 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1199 if (fs.access_flags().is_static()) {
1200 fieldDescriptor fd;
1201 fd.initialize(this, fs.index());
1202 cl->do_field(&fd);
1203 }
1204 }
1205 }
1206
1207
1208 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
1209 instanceKlassHandle h_this(THREAD, this);
1210 do_local_static_fields_impl(h_this, f, CHECK);
1211 }
1212
1213
1214 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
1215 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
1216 if (fs.access_flags().is_static()) {
1217 fieldDescriptor fd;
1218 fd.initialize(this_oop(), fs.index());
1219 f(&fd, CHECK);
1220 }
1221 }
1222 }
1223
1224
1225 static int compare_fields_by_offset(int* a, int* b) {
1226 return a[0] - b[0];
1227 }
1228
1229 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1230 InstanceKlass* super = superklass();
1231 if (super != NULL) {
1232 super->do_nonstatic_fields(cl);
1233 }
1234 fieldDescriptor fd;
1235 int length = java_fields_count();
1236 // In DebugInfo nonstatic fields are sorted by offset.
1237 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1238 int j = 0;
1239 for (int i = 0; i < length; i += 1) {
1240 fd.initialize(this, i);
1241 if (!fd.is_static()) {
1242 fields_sorted[j + 0] = fd.offset();
1243 fields_sorted[j + 1] = i;
1244 j += 2;
1245 }
1246 }
1247 if (j > 0) {
1248 length = j;
1249 // _sort_Fn is defined in growableArray.hpp.
1250 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1251 for (int i = 0; i < length; i += 2) {
1252 fd.initialize(this, fields_sorted[i + 1]);
1253 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1254 cl->do_field(&fd);
1255 }
1256 }
1257 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1258 }
1259
1260
1261 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1262 if (array_klasses() != NULL)
1263 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1264 }
1265
1266 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1267 if (array_klasses() != NULL)
1268 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1269 }
1270
1271
1272 void InstanceKlass::with_array_klasses_do(void f(Klass* k)) {
1273 f(this);
1274 array_klasses_do(f);
1275 }
1276
1277 #ifdef ASSERT
1278 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1279 int len = methods->length();
1280 for (int index = 0; index < len; index++) {
1281 Method* m = methods->at(index);
1282 assert(m->is_method(), "must be method");
1283 if (m->signature() == signature && m->name() == name) {
1284 return index;
1285 }
1286 }
1287 return -1;
1288 }
1289 #endif
1290
1291 static int binary_search(Array<Method*>* methods, Symbol* name) {
1292 int len = methods->length();
1293 // methods are sorted, so do binary search
1294 int l = 0;
1295 int h = len - 1;
1296 while (l <= h) {
1297 int mid = (l + h) >> 1;
1298 Method* m = methods->at(mid);
1299 assert(m->is_method(), "must be method");
1300 int res = m->name()->fast_compare(name);
1301 if (res == 0) {
1302 return mid;
1303 } else if (res < 0) {
1304 l = mid + 1;
1305 } else {
1306 h = mid - 1;
1307 }
1308 }
1309 return -1;
1310 }
1311
1312 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1313 return InstanceKlass::find_method(methods(), name, signature);
1314 }
1315
1316 Method* InstanceKlass::find_method(
1317 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1318 int hit = binary_search(methods, name);
1319 if (hit != -1) {
1320 Method* m = methods->at(hit);
1321 // Do linear search to find matching signature. First, quick check
1322 // for common case
1323 if (m->signature() == signature) return m;
1324 // search downwards through overloaded methods
1325 int i;
1326 for (i = hit - 1; i >= 0; --i) {
1327 Method* m = methods->at(i);
1328 assert(m->is_method(), "must be method");
1329 if (m->name() != name) break;
1330 if (m->signature() == signature) return m;
1331 }
1332 // search upwards
1333 for (i = hit + 1; i < methods->length(); ++i) {
1334 Method* m = methods->at(i);
1335 assert(m->is_method(), "must be method");
1336 if (m->name() != name) break;
1337 if (m->signature() == signature) return m;
1338 }
1339 // not found
1340 #ifdef ASSERT
1341 int index = linear_search(methods, name, signature);
1342 assert(index == -1, err_msg("binary search should have found entry %d", index));
1343 #endif
1344 }
1345 return NULL;
1346 }
1347
1348 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1349 return find_method_by_name(methods(), name, end);
1350 }
1351
1352 int InstanceKlass::find_method_by_name(
1353 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1354 assert(end_ptr != NULL, "just checking");
1355 int start = binary_search(methods, name);
1356 int end = start + 1;
1357 if (start != -1) {
1358 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1359 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1360 *end_ptr = end;
1361 return start;
1362 }
1363 return -1;
1364 }
1365
1366 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1367 Klass* klass = const_cast<InstanceKlass*>(this);
1368 while (klass != NULL) {
1369 Method* method = InstanceKlass::cast(klass)->find_method(name, signature);
1370 if (method != NULL) return method;
1371 klass = InstanceKlass::cast(klass)->super();
1372 }
1373 return NULL;
1374 }
1375
1376 // lookup a method in all the interfaces that this class implements
1377 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1378 Symbol* signature) const {
1379 Array<Klass*>* all_ifs = transitive_interfaces();
1380 int num_ifs = all_ifs->length();
1381 InstanceKlass *ik = NULL;
1382 for (int i = 0; i < num_ifs; i++) {
1383 ik = InstanceKlass::cast(all_ifs->at(i));
1384 Method* m = ik->lookup_method(name, signature);
1385 if (m != NULL) {
1386 return m;
1387 }
1388 }
1389 return NULL;
1390 }
1391
1392 /* jni_id_for_impl for jfieldIds only */
1393 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1394 MutexLocker ml(JfieldIdCreation_lock);
1395 // Retry lookup after we got the lock
1396 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1397 if (probe == NULL) {
1398 // Slow case, allocate new static field identifier
1399 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1400 this_oop->set_jni_ids(probe);
1401 }
1402 return probe;
1403 }
1404
1405
1406 /* jni_id_for for jfieldIds only */
1407 JNIid* InstanceKlass::jni_id_for(int offset) {
1408 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1409 if (probe == NULL) {
1410 probe = jni_id_for_impl(this, offset);
1411 }
1412 return probe;
1413 }
1414
1415 u2 InstanceKlass::enclosing_method_data(int offset) {
1416 Array<jushort>* inner_class_list = inner_classes();
1417 if (inner_class_list == NULL) {
1418 return 0;
1419 }
1420 int length = inner_class_list->length();
1421 if (length % inner_class_next_offset == 0) {
1422 return 0;
1423 } else {
1424 int index = length - enclosing_method_attribute_size;
1425 assert(offset < enclosing_method_attribute_size, "invalid offset");
1426 return inner_class_list->at(index + offset);
1427 }
1428 }
1429
1430 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1431 u2 method_index) {
1432 Array<jushort>* inner_class_list = inner_classes();
1433 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1434 int length = inner_class_list->length();
1435 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1436 int index = length - enclosing_method_attribute_size;
1437 inner_class_list->at_put(
1438 index + enclosing_method_class_index_offset, class_index);
1439 inner_class_list->at_put(
1440 index + enclosing_method_method_index_offset, method_index);
1441 }
1442 }
1443
1444 // Lookup or create a jmethodID.
1445 // This code is called by the VMThread and JavaThreads so the
1446 // locking has to be done very carefully to avoid deadlocks
1447 // and/or other cache consistency problems.
1448 //
1449 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1450 size_t idnum = (size_t)method_h->method_idnum();
1451 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1452 size_t length = 0;
1453 jmethodID id = NULL;
1454
1455 // We use a double-check locking idiom here because this cache is
1456 // performance sensitive. In the normal system, this cache only
1457 // transitions from NULL to non-NULL which is safe because we use
1458 // release_set_methods_jmethod_ids() to advertise the new cache.
1459 // A partially constructed cache should never be seen by a racing
1460 // thread. We also use release_store_ptr() to save a new jmethodID
1461 // in the cache so a partially constructed jmethodID should never be
1462 // seen either. Cache reads of existing jmethodIDs proceed without a
1463 // lock, but cache writes of a new jmethodID requires uniqueness and
1464 // creation of the cache itself requires no leaks so a lock is
1465 // generally acquired in those two cases.
1466 //
1467 // If the RedefineClasses() API has been used, then this cache can
1468 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1469 // Cache creation requires no leaks and we require safety between all
1470 // cache accesses and freeing of the old cache so a lock is generally
1471 // acquired when the RedefineClasses() API has been used.
1472
1473 if (jmeths != NULL) {
1474 // the cache already exists
1475 if (!ik_h->idnum_can_increment()) {
1476 // the cache can't grow so we can just get the current values
1477 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1478 } else {
1479 // cache can grow so we have to be more careful
1480 if (Threads::number_of_threads() == 0 ||
1481 SafepointSynchronize::is_at_safepoint()) {
1482 // we're single threaded or at a safepoint - no locking needed
1483 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1484 } else {
1485 MutexLocker ml(JmethodIdCreation_lock);
1486 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1487 }
1488 }
1489 }
1490 // implied else:
1491 // we need to allocate a cache so default length and id values are good
1492
1493 if (jmeths == NULL || // no cache yet
1494 length <= idnum || // cache is too short
1495 id == NULL) { // cache doesn't contain entry
1496
1497 // This function can be called by the VMThread so we have to do all
1498 // things that might block on a safepoint before grabbing the lock.
1499 // Otherwise, we can deadlock with the VMThread or have a cache
1500 // consistency issue. These vars keep track of what we might have
1501 // to free after the lock is dropped.
1502 jmethodID to_dealloc_id = NULL;
1503 jmethodID* to_dealloc_jmeths = NULL;
1504
1505 // may not allocate new_jmeths or use it if we allocate it
1506 jmethodID* new_jmeths = NULL;
1507 if (length <= idnum) {
1508 // allocate a new cache that might be used
1509 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1510 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1511 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1512 // cache size is stored in element[0], other elements offset by one
1513 new_jmeths[0] = (jmethodID)size;
1514 }
1515
1516 // allocate a new jmethodID that might be used
1517 jmethodID new_id = NULL;
1518 if (method_h->is_old() && !method_h->is_obsolete()) {
1519 // The method passed in is old (but not obsolete), we need to use the current version
1520 Method* current_method = ik_h->method_with_idnum((int)idnum);
1521 assert(current_method != NULL, "old and but not obsolete, so should exist");
1522 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1523 } else {
1524 // It is the current version of the method or an obsolete method,
1525 // use the version passed in
1526 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1527 }
1528
1529 if (Threads::number_of_threads() == 0 ||
1530 SafepointSynchronize::is_at_safepoint()) {
1531 // we're single threaded or at a safepoint - no locking needed
1532 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1533 &to_dealloc_id, &to_dealloc_jmeths);
1534 } else {
1535 MutexLocker ml(JmethodIdCreation_lock);
1536 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1537 &to_dealloc_id, &to_dealloc_jmeths);
1538 }
1539
1540 // The lock has been dropped so we can free resources.
1541 // Free up either the old cache or the new cache if we allocated one.
1542 if (to_dealloc_jmeths != NULL) {
1543 FreeHeap(to_dealloc_jmeths);
1544 }
1545 // free up the new ID since it wasn't needed
1546 if (to_dealloc_id != NULL) {
1547 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1548 }
1549 }
1550 return id;
1551 }
1552
1553
1554 // Common code to fetch the jmethodID from the cache or update the
1555 // cache with the new jmethodID. This function should never do anything
1556 // that causes the caller to go to a safepoint or we can deadlock with
1557 // the VMThread or have cache consistency issues.
1558 //
1559 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1560 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1561 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1562 jmethodID** to_dealloc_jmeths_p) {
1563 assert(new_id != NULL, "sanity check");
1564 assert(to_dealloc_id_p != NULL, "sanity check");
1565 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1566 assert(Threads::number_of_threads() == 0 ||
1567 SafepointSynchronize::is_at_safepoint() ||
1568 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1569
1570 // reacquire the cache - we are locked, single threaded or at a safepoint
1571 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1572 jmethodID id = NULL;
1573 size_t length = 0;
1574
1575 if (jmeths == NULL || // no cache yet
1576 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1577 if (jmeths != NULL) {
1578 // copy any existing entries from the old cache
1579 for (size_t index = 0; index < length; index++) {
1580 new_jmeths[index+1] = jmeths[index+1];
1581 }
1582 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1583 }
1584 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1585 } else {
1586 // fetch jmethodID (if any) from the existing cache
1587 id = jmeths[idnum+1];
1588 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1589 }
1590 if (id == NULL) {
1591 // No matching jmethodID in the existing cache or we have a new
1592 // cache or we just grew the cache. This cache write is done here
1593 // by the first thread to win the foot race because a jmethodID
1594 // needs to be unique once it is generally available.
1595 id = new_id;
1596
1597 // The jmethodID cache can be read while unlocked so we have to
1598 // make sure the new jmethodID is complete before installing it
1599 // in the cache.
1600 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1601 } else {
1602 *to_dealloc_id_p = new_id; // save new id for later delete
1603 }
1604 return id;
1605 }
1606
1607
1608 // Common code to get the jmethodID cache length and the jmethodID
1609 // value at index idnum if there is one.
1610 //
1611 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1612 size_t idnum, size_t *length_p, jmethodID* id_p) {
1613 assert(cache != NULL, "sanity check");
1614 assert(length_p != NULL, "sanity check");
1615 assert(id_p != NULL, "sanity check");
1616
1617 // cache size is stored in element[0], other elements offset by one
1618 *length_p = (size_t)cache[0];
1619 if (*length_p <= idnum) { // cache is too short
1620 *id_p = NULL;
1621 } else {
1622 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1623 }
1624 }
1625
1626
1627 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1628 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1629 size_t idnum = (size_t)method->method_idnum();
1630 jmethodID* jmeths = methods_jmethod_ids_acquire();
1631 size_t length; // length assigned as debugging crumb
1632 jmethodID id = NULL;
1633 if (jmeths != NULL && // If there is a cache
1634 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1635 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1636 }
1637 return id;
1638 }
1639
1640
1641 // Cache an itable index
1642 void InstanceKlass::set_cached_itable_index(size_t idnum, int index) {
1643 int* indices = methods_cached_itable_indices_acquire();
1644 int* to_dealloc_indices = NULL;
1645
1646 // We use a double-check locking idiom here because this cache is
1647 // performance sensitive. In the normal system, this cache only
1648 // transitions from NULL to non-NULL which is safe because we use
1649 // release_set_methods_cached_itable_indices() to advertise the
1650 // new cache. A partially constructed cache should never be seen
1651 // by a racing thread. Cache reads and writes proceed without a
1652 // lock, but creation of the cache itself requires no leaks so a
1653 // lock is generally acquired in that case.
1654 //
1655 // If the RedefineClasses() API has been used, then this cache can
1656 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1657 // Cache creation requires no leaks and we require safety between all
1658 // cache accesses and freeing of the old cache so a lock is generally
1659 // acquired when the RedefineClasses() API has been used.
1660
1661 if (indices == NULL || idnum_can_increment()) {
1662 // we need a cache or the cache can grow
1663 MutexLocker ml(JNICachedItableIndex_lock);
1664 // reacquire the cache to see if another thread already did the work
1665 indices = methods_cached_itable_indices_acquire();
1666 size_t length = 0;
1667 // cache size is stored in element[0], other elements offset by one
1668 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1669 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1670 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1, mtClass);
1671 new_indices[0] = (int)size;
1672 // copy any existing entries
1673 size_t i;
1674 for (i = 0; i < length; i++) {
1675 new_indices[i+1] = indices[i+1];
1676 }
1677 // Set all the rest to -1
1678 for (i = length; i < size; i++) {
1679 new_indices[i+1] = -1;
1680 }
1681 if (indices != NULL) {
1682 // We have an old cache to delete so save it for after we
1683 // drop the lock.
1684 to_dealloc_indices = indices;
1685 }
1686 release_set_methods_cached_itable_indices(indices = new_indices);
1687 }
1688
1689 if (idnum_can_increment()) {
1690 // this cache can grow so we have to write to it safely
1691 indices[idnum+1] = index;
1692 }
1693 } else {
1694 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1695 }
1696
1697 if (!idnum_can_increment()) {
1698 // The cache cannot grow and this JNI itable index value does not
1699 // have to be unique like a jmethodID. If there is a race to set it,
1700 // it doesn't matter.
1701 indices[idnum+1] = index;
1702 }
1703
1704 if (to_dealloc_indices != NULL) {
1705 // we allocated a new cache so free the old one
1706 FreeHeap(to_dealloc_indices);
1707 }
1708 }
1709
1710
1711 // Retrieve a cached itable index
1712 int InstanceKlass::cached_itable_index(size_t idnum) {
1713 int* indices = methods_cached_itable_indices_acquire();
1714 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1715 // indices exist and are long enough, retrieve possible cached
1716 return indices[idnum+1];
1717 }
1718 return -1;
1719 }
1720
1721
1722 //
1723 // Walk the list of dependent nmethods searching for nmethods which
1724 // are dependent on the changes that were passed in and mark them for
1725 // deoptimization. Returns the number of nmethods found.
1726 //
1727 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1728 assert_locked_or_safepoint(CodeCache_lock);
1729 int found = 0;
1730 nmethodBucket* b = _dependencies;
1731 while (b != NULL) {
1732 nmethod* nm = b->get_nmethod();
1733 // since dependencies aren't removed until an nmethod becomes a zombie,
1734 // the dependency list may contain nmethods which aren't alive.
1735 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1736 if (TraceDependencies) {
1737 ResourceMark rm;
1738 tty->print_cr("Marked for deoptimization");
1739 tty->print_cr(" context = %s", this->external_name());
1740 changes.print();
1741 nm->print();
1742 nm->print_dependencies();
1743 }
1744 nm->mark_for_deoptimization();
1745 found++;
1746 }
1747 b = b->next();
1748 }
1749 return found;
1750 }
1751
1752
1753 //
1754 // Add an nmethodBucket to the list of dependencies for this nmethod.
1755 // It's possible that an nmethod has multiple dependencies on this klass
1756 // so a count is kept for each bucket to guarantee that creation and
1757 // deletion of dependencies is consistent.
1758 //
1759 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1760 assert_locked_or_safepoint(CodeCache_lock);
1761 nmethodBucket* b = _dependencies;
1762 nmethodBucket* last = NULL;
1763 while (b != NULL) {
1764 if (nm == b->get_nmethod()) {
1765 b->increment();
1766 return;
1767 }
1768 b = b->next();
1769 }
1770 _dependencies = new nmethodBucket(nm, _dependencies);
1771 }
1772
1773
1774 //
1775 // Decrement count of the nmethod in the dependency list and remove
1776 // the bucket competely when the count goes to 0. This method must
1777 // find a corresponding bucket otherwise there's a bug in the
1778 // recording of dependecies.
1779 //
1780 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1781 assert_locked_or_safepoint(CodeCache_lock);
1782 nmethodBucket* b = _dependencies;
1783 nmethodBucket* last = NULL;
1784 while (b != NULL) {
1785 if (nm == b->get_nmethod()) {
1786 if (b->decrement() == 0) {
1787 if (last == NULL) {
1788 _dependencies = b->next();
1789 } else {
1790 last->set_next(b->next());
1791 }
1792 delete b;
1793 }
1794 return;
1795 }
1796 last = b;
1797 b = b->next();
1798 }
1799 #ifdef ASSERT
1800 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1801 nm->print();
1802 #endif // ASSERT
1803 ShouldNotReachHere();
1804 }
1805
1806
1807 #ifndef PRODUCT
1808 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1809 nmethodBucket* b = _dependencies;
1810 int idx = 0;
1811 while (b != NULL) {
1812 nmethod* nm = b->get_nmethod();
1813 tty->print("[%d] count=%d { ", idx++, b->count());
1814 if (!verbose) {
1815 nm->print_on(tty, "nmethod");
1816 tty->print_cr(" } ");
1817 } else {
1818 nm->print();
1819 nm->print_dependencies();
1820 tty->print_cr("--- } ");
1821 }
1822 b = b->next();
1823 }
1824 }
1825
1826
1827 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1828 nmethodBucket* b = _dependencies;
1829 while (b != NULL) {
1830 if (nm == b->get_nmethod()) {
1831 return true;
1832 }
1833 b = b->next();
1834 }
1835 return false;
1836 }
1837 #endif //PRODUCT
1838
1839
1840 // Garbage collection
1841
1842 void InstanceKlass::oops_do(OopClosure* cl) {
1843 Klass::oops_do(cl);
1844
1845 cl->do_oop(adr_protection_domain());
1846 cl->do_oop(adr_signers());
1847 cl->do_oop(adr_init_lock());
1848
1849 // Don't walk the arrays since they are walked from the ClassLoaderData objects.
1850 }
1851
1852 #ifdef ASSERT
1853 template <class T> void assert_is_in(T *p) {
1854 T heap_oop = oopDesc::load_heap_oop(p);
1855 if (!oopDesc::is_null(heap_oop)) {
1856 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1857 assert(Universe::heap()->is_in(o), "should be in heap");
1858 }
1859 }
1860 template <class T> void assert_is_in_closed_subset(T *p) {
1861 T heap_oop = oopDesc::load_heap_oop(p);
1862 if (!oopDesc::is_null(heap_oop)) {
1863 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1864 assert(Universe::heap()->is_in_closed_subset(o),
1865 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1866 }
1867 }
1868 template <class T> void assert_is_in_reserved(T *p) {
1869 T heap_oop = oopDesc::load_heap_oop(p);
1870 if (!oopDesc::is_null(heap_oop)) {
1871 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1872 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1873 }
1874 }
1875 template <class T> void assert_nothing(T *p) {}
1876
1877 #else
1878 template <class T> void assert_is_in(T *p) {}
1879 template <class T> void assert_is_in_closed_subset(T *p) {}
1880 template <class T> void assert_is_in_reserved(T *p) {}
1881 template <class T> void assert_nothing(T *p) {}
1882 #endif // ASSERT
1883
1884 //
1885 // Macros that iterate over areas of oops which are specialized on type of
1886 // oop pointer either narrow or wide, depending on UseCompressedOops
1887 //
1888 // Parameters are:
1889 // T - type of oop to point to (either oop or narrowOop)
1890 // start_p - starting pointer for region to iterate over
1891 // count - number of oops or narrowOops to iterate over
1892 // do_oop - action to perform on each oop (it's arbitrary C code which
1893 // makes it more efficient to put in a macro rather than making
1894 // it a template function)
1895 // assert_fn - assert function which is template function because performance
1896 // doesn't matter when enabled.
1897 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1898 T, start_p, count, do_oop, \
1899 assert_fn) \
1900 { \
1901 T* p = (T*)(start_p); \
1902 T* const end = p + (count); \
1903 while (p < end) { \
1904 (assert_fn)(p); \
1905 do_oop; \
1906 ++p; \
1907 } \
1908 }
1909
1910 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1911 T, start_p, count, do_oop, \
1912 assert_fn) \
1913 { \
1914 T* const start = (T*)(start_p); \
1915 T* p = start + (count); \
1916 while (start < p) { \
1917 --p; \
1918 (assert_fn)(p); \
1919 do_oop; \
1920 } \
1921 }
1922
1923 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1924 T, start_p, count, low, high, \
1925 do_oop, assert_fn) \
1926 { \
1927 T* const l = (T*)(low); \
1928 T* const h = (T*)(high); \
1929 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1930 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1931 "bounded region must be properly aligned"); \
1932 T* p = (T*)(start_p); \
1933 T* end = p + (count); \
1934 if (p < l) p = l; \
1935 if (end > h) end = h; \
1936 while (p < end) { \
1937 (assert_fn)(p); \
1938 do_oop; \
1939 ++p; \
1940 } \
1941 }
1942
1943
1944 // The following macros call specialized macros, passing either oop or
1945 // narrowOop as the specialization type. These test the UseCompressedOops
1946 // flag.
1947 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
1948 { \
1949 /* Compute oopmap block range. The common case \
1950 is nonstatic_oop_map_size == 1. */ \
1951 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1952 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1953 if (UseCompressedOops) { \
1954 while (map < end_map) { \
1955 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1956 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1957 do_oop, assert_fn) \
1958 ++map; \
1959 } \
1960 } else { \
1961 while (map < end_map) { \
1962 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1963 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1964 do_oop, assert_fn) \
1965 ++map; \
1966 } \
1967 } \
1968 }
1969
1970 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
1971 { \
1972 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
1973 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
1974 if (UseCompressedOops) { \
1975 while (start_map < map) { \
1976 --map; \
1977 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
1978 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1979 do_oop, assert_fn) \
1980 } \
1981 } else { \
1982 while (start_map < map) { \
1983 --map; \
1984 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
1985 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1986 do_oop, assert_fn) \
1987 } \
1988 } \
1989 }
1990
1991 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
1992 assert_fn) \
1993 { \
1994 /* Compute oopmap block range. The common case is \
1995 nonstatic_oop_map_size == 1, so we accept the \
1996 usually non-existent extra overhead of examining \
1997 all the maps. */ \
1998 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1999 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2000 if (UseCompressedOops) { \
2001 while (map < end_map) { \
2002 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2003 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2004 low, high, \
2005 do_oop, assert_fn) \
2006 ++map; \
2007 } \
2008 } else { \
2009 while (map < end_map) { \
2010 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2011 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2012 low, high, \
2013 do_oop, assert_fn) \
2014 ++map; \
2015 } \
2016 } \
2017 }
2018
2019 void InstanceKlass::oop_follow_contents(oop obj) {
2020 assert(obj != NULL, "can't follow the content of NULL object");
2021 MarkSweep::follow_klass(obj->klass());
2022 InstanceKlass_OOP_MAP_ITERATE( \
2023 obj, \
2024 MarkSweep::mark_and_push(p), \
2025 assert_is_in_closed_subset)
2026 }
2027
2028 #ifndef SERIALGC
2029 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2030 oop obj) {
2031 assert(obj != NULL, "can't follow the content of NULL object");
2032 PSParallelCompact::follow_klass(cm, obj->klass());
2033 // Only mark the header and let the scan of the meta-data mark
2034 // everything else.
2035 InstanceKlass_OOP_MAP_ITERATE( \
2036 obj, \
2037 PSParallelCompact::mark_and_push(cm, p), \
2038 assert_is_in)
2039 }
2040 #endif // SERIALGC
2041
2042 // closure's do_metadata() method dictates whether the given closure should be
2043 // applied to the klass ptr in the object header.
2044
2045 #define if_do_metadata_checked(closure, nv_suffix) \
2046 /* Make sure the non-virtual and the virtual versions match. */ \
2047 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2048 "Inconsistency in do_metadata"); \
2049 if (closure->do_metadata##nv_suffix())
2050
2051 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2052 \
2053 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2054 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2055 /* header */ \
2056 if_do_metadata_checked(closure, nv_suffix) { \
2057 closure->do_klass##nv_suffix(obj->klass()); \
2058 } \
2059 InstanceKlass_OOP_MAP_ITERATE( \
2060 obj, \
2061 SpecializationStats:: \
2062 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2063 (closure)->do_oop##nv_suffix(p), \
2064 assert_is_in_closed_subset) \
2065 return size_helper(); \
2066 }
2067
2068 #ifndef SERIALGC
2069 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2070 \
2071 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2072 OopClosureType* closure) { \
2073 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2074 /* header */ \
2075 if_do_metadata_checked(closure, nv_suffix) { \
2076 closure->do_klass##nv_suffix(obj->klass()); \
2077 } \
2078 /* instance variables */ \
2079 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2080 obj, \
2081 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2082 (closure)->do_oop##nv_suffix(p), \
2083 assert_is_in_closed_subset) \
2084 return size_helper(); \
2085 }
2086 #endif // !SERIALGC
2087
2088 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2089 \
2090 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2091 OopClosureType* closure, \
2092 MemRegion mr) { \
2093 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2094 if_do_metadata_checked(closure, nv_suffix) { \
2095 if (mr.contains(obj)) { \
2096 closure->do_klass##nv_suffix(obj->klass()); \
2097 } \
2098 } \
2099 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2100 obj, mr.start(), mr.end(), \
2101 (closure)->do_oop##nv_suffix(p), \
2102 assert_is_in_closed_subset) \
2103 return size_helper(); \
2104 }
2105
2106 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2107 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2108 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2109 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2110 #ifndef SERIALGC
2111 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2112 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2113 #endif // !SERIALGC
2114
2115 int InstanceKlass::oop_adjust_pointers(oop obj) {
2116 int size = size_helper();
2117 InstanceKlass_OOP_MAP_ITERATE( \
2118 obj, \
2119 MarkSweep::adjust_pointer(p), \
2120 assert_is_in)
2121 MarkSweep::adjust_klass(obj->klass());
2122 return size;
2123 }
2124
2125 #ifndef SERIALGC
2126 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2127 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2128 obj, \
2129 if (PSScavenge::should_scavenge(p)) { \
2130 pm->claim_or_forward_depth(p); \
2131 }, \
2132 assert_nothing )
2133 }
2134
2135 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2136 int size = size_helper();
2137 InstanceKlass_OOP_MAP_ITERATE( \
2138 obj, \
2139 PSParallelCompact::adjust_pointer(p), \
2140 assert_is_in)
2141 obj->update_header(cm);
2142 return size;
2143 }
2144
2145 #endif // SERIALGC
2146
2147 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2148 assert(is_loader_alive(is_alive), "this klass should be live");
2149 if (is_interface()) {
2150 if (ClassUnloading) {
2151 Klass* impl = implementor();
2152 if (impl != NULL) {
2153 if (!impl->is_loader_alive(is_alive)) {
2154 // remove this guy
2155 *adr_implementor() = NULL;
2156 }
2157 }
2158 }
2159 }
2160 }
2161
2162 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2163 #ifdef COMPILER2
2164 // Currently only used by C2.
2165 for (int m = 0; m < methods()->length(); m++) {
2166 MethodData* mdo = methods()->at(m)->method_data();
2167 if (mdo != NULL) {
2168 for (ProfileData* data = mdo->first_data();
2169 mdo->is_valid(data);
2170 data = mdo->next_data(data)) {
2171 data->clean_weak_klass_links(is_alive);
2172 }
2173 }
2174 }
2175 #else
2176 #ifdef ASSERT
2177 // Verify that we haven't started to use MDOs for C1.
2178 for (int m = 0; m < methods()->length(); m++) {
2179 MethodData* mdo = methods()->at(m)->method_data();
2180 assert(mdo == NULL, "Didn't expect C1 to use MDOs");
2181 }
2182 #endif // ASSERT
2183 #endif // !COMPILER2
2184 }
2185
2186
2187 static void remove_unshareable_in_class(Klass* k) {
2188 // remove klass's unshareable info
2189 k->remove_unshareable_info();
2190 }
2191
2192 void InstanceKlass::remove_unshareable_info() {
2193 Klass::remove_unshareable_info();
2194 // Unlink the class
2195 if (is_linked()) {
2196 unlink_class();
2197 }
2198 init_implementor();
2199
2200 constants()->remove_unshareable_info();
2201
2202 for (int i = 0; i < methods()->length(); i++) {
2203 Method* m = methods()->at(i);
2204 m->remove_unshareable_info();
2205 }
2206
2207 // Need to reinstate when reading back the class.
2208 set_init_lock(NULL);
2209
2210 // do array classes also.
2211 array_klasses_do(remove_unshareable_in_class);
2212 }
2213
2214 void restore_unshareable_in_class(Klass* k, TRAPS) {
2215 k->restore_unshareable_info(CHECK);
2216 }
2217
2218 void InstanceKlass::restore_unshareable_info(TRAPS) {
2219 Klass::restore_unshareable_info(CHECK);
2220 instanceKlassHandle ik(THREAD, this);
2221
2222 Array<Method*>* methods = ik->methods();
2223 int num_methods = methods->length();
2224 for (int index2 = 0; index2 < num_methods; ++index2) {
2225 methodHandle m(THREAD, methods->at(index2));
2226 m()->link_method(m, CHECK);
2227 // restore method's vtable by calling a virtual function
2228 m->restore_vtable();
2229 }
2230 if (JvmtiExport::has_redefined_a_class()) {
2231 // Reinitialize vtable because RedefineClasses may have changed some
2232 // entries in this vtable for super classes so the CDS vtable might
2233 // point to old or obsolete entries. RedefineClasses doesn't fix up
2234 // vtables in the shared system dictionary, only the main one.
2235 // It also redefines the itable too so fix that too.
2236 ResourceMark rm(THREAD);
2237 ik->vtable()->initialize_vtable(false, CHECK);
2238 ik->itable()->initialize_itable(false, CHECK);
2239 }
2240
2241 // Allocate a simple java object for a lock.
2242 // This needs to be a java object because during class initialization
2243 // it can be held across a java call.
2244 typeArrayOop r = oopFactory::new_typeArray(T_INT, 0, CHECK);
2245 Handle h(THREAD, (oop)r);
2246 ik->set_init_lock(h());
2247
2248 // restore constant pool resolved references
2249 ik->constants()->restore_unshareable_info(CHECK);
2250
2251 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2252 }
2253
2254 static void clear_all_breakpoints(Method* m) {
2255 m->clear_all_breakpoints();
2256 }
2257
2258 void InstanceKlass::release_C_heap_structures() {
2259 // Deallocate oop map cache
2260 if (_oop_map_cache != NULL) {
2261 delete _oop_map_cache;
2262 _oop_map_cache = NULL;
2263 }
2264
2265 // Deallocate JNI identifiers for jfieldIDs
2266 JNIid::deallocate(jni_ids());
2267 set_jni_ids(NULL);
2268
2269 jmethodID* jmeths = methods_jmethod_ids_acquire();
2270 if (jmeths != (jmethodID*)NULL) {
2271 release_set_methods_jmethod_ids(NULL);
2272 FreeHeap(jmeths);
2273 }
2274
2275 int* indices = methods_cached_itable_indices_acquire();
2276 if (indices != (int*)NULL) {
2277 release_set_methods_cached_itable_indices(NULL);
2278 FreeHeap(indices);
2279 }
2280
2281 // release dependencies
2282 nmethodBucket* b = _dependencies;
2283 _dependencies = NULL;
2284 while (b != NULL) {
2285 nmethodBucket* next = b->next();
2286 delete b;
2287 b = next;
2288 }
2289
2290 // Deallocate breakpoint records
2291 if (breakpoints() != 0x0) {
2292 methods_do(clear_all_breakpoints);
2293 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2294 }
2295
2296 // deallocate information about previous versions
2297 if (_previous_versions != NULL) {
2298 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2299 PreviousVersionNode * pv_node = _previous_versions->at(i);
2300 delete pv_node;
2301 }
2302 delete _previous_versions;
2303 _previous_versions = NULL;
2304 }
2305
2306 // deallocate the cached class file
2307 if (_cached_class_file_bytes != NULL) {
2308 os::free(_cached_class_file_bytes, mtClass);
2309 _cached_class_file_bytes = NULL;
2310 _cached_class_file_len = 0;
2311 }
2312
2313 // Decrement symbol reference counts associated with the unloaded class.
2314 if (_name != NULL) _name->decrement_refcount();
2315 // unreference array name derived from this class name (arrays of an unloaded
2316 // class can't be referenced anymore).
2317 if (_array_name != NULL) _array_name->decrement_refcount();
2318 if (_source_file_name != NULL) _source_file_name->decrement_refcount();
2319 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2320 }
2321
2322 void InstanceKlass::set_source_file_name(Symbol* n) {
2323 _source_file_name = n;
2324 if (_source_file_name != NULL) _source_file_name->increment_refcount();
2325 }
2326
2327 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2328 if (array == NULL) {
2329 _source_debug_extension = NULL;
2330 } else {
2331 // Adding one to the attribute length in order to store a null terminator
2332 // character could cause an overflow because the attribute length is
2333 // already coded with an u4 in the classfile, but in practice, it's
2334 // unlikely to happen.
2335 assert((length+1) > length, "Overflow checking");
2336 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2337 for (int i = 0; i < length; i++) {
2338 sde[i] = array[i];
2339 }
2340 sde[length] = '\0';
2341 _source_debug_extension = sde;
2342 }
2343 }
2344
2345 address InstanceKlass::static_field_addr(int offset) {
2346 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror());
2347 }
2348
2349
2350 const char* InstanceKlass::signature_name() const {
2351 const char* src = (const char*) (name()->as_C_string());
2352 const int src_length = (int)strlen(src);
2353 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
2354 int src_index = 0;
2355 int dest_index = 0;
2356 dest[dest_index++] = 'L';
2357 while (src_index < src_length) {
2358 dest[dest_index++] = src[src_index++];
2359 }
2360 dest[dest_index++] = ';';
2361 dest[dest_index] = '\0';
2362 return dest;
2363 }
2364
2365 // different verisons of is_same_class_package
2366 bool InstanceKlass::is_same_class_package(Klass* class2) {
2367 Klass* class1 = this;
2368 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2369 Symbol* classname1 = class1->name();
2370
2371 if (class2->oop_is_objArray()) {
2372 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2373 }
2374 oop classloader2;
2375 if (class2->oop_is_instance()) {
2376 classloader2 = InstanceKlass::cast(class2)->class_loader();
2377 } else {
2378 assert(class2->oop_is_typeArray(), "should be type array");
2379 classloader2 = NULL;
2380 }
2381 Symbol* classname2 = class2->name();
2382
2383 return InstanceKlass::is_same_class_package(classloader1, classname1,
2384 classloader2, classname2);
2385 }
2386
2387 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2388 Klass* class1 = this;
2389 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2390 Symbol* classname1 = class1->name();
2391
2392 return InstanceKlass::is_same_class_package(classloader1, classname1,
2393 classloader2, classname2);
2394 }
2395
2396 // return true if two classes are in the same package, classloader
2397 // and classname information is enough to determine a class's package
2398 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2399 oop class_loader2, Symbol* class_name2) {
2400 if (class_loader1 != class_loader2) {
2401 return false;
2402 } else if (class_name1 == class_name2) {
2403 return true; // skip painful bytewise comparison
2404 } else {
2405 ResourceMark rm;
2406
2407 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2408 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2409 // Otherwise, we just compare jbyte values between the strings.
2410 const jbyte *name1 = class_name1->base();
2411 const jbyte *name2 = class_name2->base();
2412
2413 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2414 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2415
2416 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2417 // One of the two doesn't have a package. Only return true
2418 // if the other one also doesn't have a package.
2419 return last_slash1 == last_slash2;
2420 } else {
2421 // Skip over '['s
2422 if (*name1 == '[') {
2423 do {
2424 name1++;
2425 } while (*name1 == '[');
2426 if (*name1 != 'L') {
2427 // Something is terribly wrong. Shouldn't be here.
2428 return false;
2429 }
2430 }
2431 if (*name2 == '[') {
2432 do {
2433 name2++;
2434 } while (*name2 == '[');
2435 if (*name2 != 'L') {
2436 // Something is terribly wrong. Shouldn't be here.
2437 return false;
2438 }
2439 }
2440
2441 // Check that package part is identical
2442 int length1 = last_slash1 - name1;
2443 int length2 = last_slash2 - name2;
2444
2445 return UTF8::equal(name1, length1, name2, length2);
2446 }
2447 }
2448 }
2449
2450 // Returns true iff super_method can be overridden by a method in targetclassname
2451 // See JSL 3rd edition 8.4.6.1
2452 // Assumes name-signature match
2453 // "this" is InstanceKlass of super_method which must exist
2454 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2455 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2456 // Private methods can not be overridden
2457 if (super_method->is_private()) {
2458 return false;
2459 }
2460 // If super method is accessible, then override
2461 if ((super_method->is_protected()) ||
2462 (super_method->is_public())) {
2463 return true;
2464 }
2465 // Package-private methods are not inherited outside of package
2466 assert(super_method->is_package_private(), "must be package private");
2467 return(is_same_class_package(targetclassloader(), targetclassname));
2468 }
2469
2470 /* defined for now in jvm.cpp, for historical reasons *--
2471 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2472 Symbol*& simple_name_result, TRAPS) {
2473 ...
2474 }
2475 */
2476
2477 // tell if two classes have the same enclosing class (at package level)
2478 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2479 Klass* class2_oop, TRAPS) {
2480 if (class2_oop == class1()) return true;
2481 if (!class2_oop->oop_is_instance()) return false;
2482 instanceKlassHandle class2(THREAD, class2_oop);
2483
2484 // must be in same package before we try anything else
2485 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2486 return false;
2487
2488 // As long as there is an outer1.getEnclosingClass,
2489 // shift the search outward.
2490 instanceKlassHandle outer1 = class1;
2491 for (;;) {
2492 // As we walk along, look for equalities between outer1 and class2.
2493 // Eventually, the walks will terminate as outer1 stops
2494 // at the top-level class around the original class.
2495 bool ignore_inner_is_member;
2496 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2497 CHECK_false);
2498 if (next == NULL) break;
2499 if (next == class2()) return true;
2500 outer1 = instanceKlassHandle(THREAD, next);
2501 }
2502
2503 // Now do the same for class2.
2504 instanceKlassHandle outer2 = class2;
2505 for (;;) {
2506 bool ignore_inner_is_member;
2507 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2508 CHECK_false);
2509 if (next == NULL) break;
2510 // Might as well check the new outer against all available values.
2511 if (next == class1()) return true;
2512 if (next == outer1()) return true;
2513 outer2 = instanceKlassHandle(THREAD, next);
2514 }
2515
2516 // If by this point we have not found an equality between the
2517 // two classes, we know they are in separate package members.
2518 return false;
2519 }
2520
2521
2522 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2523 jint access = access_flags().as_int();
2524
2525 // But check if it happens to be member class.
2526 instanceKlassHandle ik(THREAD, this);
2527 InnerClassesIterator iter(ik);
2528 for (; !iter.done(); iter.next()) {
2529 int ioff = iter.inner_class_info_index();
2530 // Inner class attribute can be zero, skip it.
2531 // Strange but true: JVM spec. allows null inner class refs.
2532 if (ioff == 0) continue;
2533
2534 // only look at classes that are already loaded
2535 // since we are looking for the flags for our self.
2536 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2537 if ((ik->name() == inner_name)) {
2538 // This is really a member class.
2539 access = iter.inner_access_flags();
2540 break;
2541 }
2542 }
2543 // Remember to strip ACC_SUPER bit
2544 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2545 }
2546
2547 jint InstanceKlass::jvmti_class_status() const {
2548 jint result = 0;
2549
2550 if (is_linked()) {
2551 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2552 }
2553
2554 if (is_initialized()) {
2555 assert(is_linked(), "Class status is not consistent");
2556 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2557 }
2558 if (is_in_error_state()) {
2559 result |= JVMTI_CLASS_STATUS_ERROR;
2560 }
2561 return result;
2562 }
2563
2564 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2565 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2566 int method_table_offset_in_words = ioe->offset()/wordSize;
2567 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2568 / itableOffsetEntry::size();
2569
2570 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2571 // If the interface isn't implemented by the receiver class,
2572 // the VM should throw IncompatibleClassChangeError.
2573 if (cnt >= nof_interfaces) {
2574 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2575 }
2576
2577 Klass* ik = ioe->interface_klass();
2578 if (ik == holder) break;
2579 }
2580
2581 itableMethodEntry* ime = ioe->first_method_entry(this);
2582 Method* m = ime[index].method();
2583 if (m == NULL) {
2584 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2585 }
2586 return m;
2587 }
2588
2589 // On-stack replacement stuff
2590 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2591 // only one compilation can be active
2592 NEEDS_CLEANUP
2593 // This is a short non-blocking critical region, so the no safepoint check is ok.
2594 OsrList_lock->lock_without_safepoint_check();
2595 assert(n->is_osr_method(), "wrong kind of nmethod");
2596 n->set_osr_link(osr_nmethods_head());
2597 set_osr_nmethods_head(n);
2598 // Raise the highest osr level if necessary
2599 if (TieredCompilation) {
2600 Method* m = n->method();
2601 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2602 }
2603 // Remember to unlock again
2604 OsrList_lock->unlock();
2605
2606 // Get rid of the osr methods for the same bci that have lower levels.
2607 if (TieredCompilation) {
2608 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2609 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2610 if (inv != NULL && inv->is_in_use()) {
2611 inv->make_not_entrant();
2612 }
2613 }
2614 }
2615 }
2616
2617
2618 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2619 // This is a short non-blocking critical region, so the no safepoint check is ok.
2620 OsrList_lock->lock_without_safepoint_check();
2621 assert(n->is_osr_method(), "wrong kind of nmethod");
2622 nmethod* last = NULL;
2623 nmethod* cur = osr_nmethods_head();
2624 int max_level = CompLevel_none; // Find the max comp level excluding n
2625 Method* m = n->method();
2626 // Search for match
2627 while(cur != NULL && cur != n) {
2628 if (TieredCompilation) {
2629 // Find max level before n
2630 max_level = MAX2(max_level, cur->comp_level());
2631 }
2632 last = cur;
2633 cur = cur->osr_link();
2634 }
2635 nmethod* next = NULL;
2636 if (cur == n) {
2637 next = cur->osr_link();
2638 if (last == NULL) {
2639 // Remove first element
2640 set_osr_nmethods_head(next);
2641 } else {
2642 last->set_osr_link(next);
2643 }
2644 }
2645 n->set_osr_link(NULL);
2646 if (TieredCompilation) {
2647 cur = next;
2648 while (cur != NULL) {
2649 // Find max level after n
2650 max_level = MAX2(max_level, cur->comp_level());
2651 cur = cur->osr_link();
2652 }
2653 m->set_highest_osr_comp_level(max_level);
2654 }
2655 // Remember to unlock again
2656 OsrList_lock->unlock();
2657 }
2658
2659 nmethod* InstanceKlass::lookup_osr_nmethod(Method* const m, int bci, int comp_level, bool match_level) const {
2660 // This is a short non-blocking critical region, so the no safepoint check is ok.
2661 OsrList_lock->lock_without_safepoint_check();
2662 nmethod* osr = osr_nmethods_head();
2663 nmethod* best = NULL;
2664 while (osr != NULL) {
2665 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2666 // There can be a time when a c1 osr method exists but we are waiting
2667 // for a c2 version. When c2 completes its osr nmethod we will trash
2668 // the c1 version and only be able to find the c2 version. However
2669 // while we overflow in the c1 code at back branches we don't want to
2670 // try and switch to the same code as we are already running
2671
2672 if (osr->method() == m &&
2673 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2674 if (match_level) {
2675 if (osr->comp_level() == comp_level) {
2676 // Found a match - return it.
2677 OsrList_lock->unlock();
2678 return osr;
2679 }
2680 } else {
2681 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2682 if (osr->comp_level() == CompLevel_highest_tier) {
2683 // Found the best possible - return it.
2684 OsrList_lock->unlock();
2685 return osr;
2686 }
2687 best = osr;
2688 }
2689 }
2690 }
2691 osr = osr->osr_link();
2692 }
2693 OsrList_lock->unlock();
2694 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2695 return best;
2696 }
2697 return NULL;
2698 }
2699
2700 // -----------------------------------------------------------------------------------------------------
2701 // Printing
2702
2703 #ifndef PRODUCT
2704
2705 #define BULLET " - "
2706
2707 static const char* state_names[] = {
2708 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2709 };
2710
2711 void InstanceKlass::print_on(outputStream* st) const {
2712 assert(is_klass(), "must be klass");
2713 Klass::print_on(st);
2714
2715 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2716 st->print(BULLET"klass size: %d", size()); st->cr();
2717 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2718 st->print(BULLET"state: "); st->print_cr(state_names[_init_state]);
2719 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2720 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2721 st->print(BULLET"sub: ");
2722 Klass* sub = subklass();
2723 int n;
2724 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2725 if (n < MaxSubklassPrintSize) {
2726 sub->print_value_on(st);
2727 st->print(" ");
2728 }
2729 }
2730 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2731 st->cr();
2732
2733 if (is_interface()) {
2734 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2735 if (nof_implementors() == 1) {
2736 st->print_cr(BULLET"implementor: ");
2737 st->print(" ");
2738 implementor()->print_value_on(st);
2739 st->cr();
2740 }
2741 }
2742
2743 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2744 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2745 if (Verbose) {
2746 Array<Method*>* method_array = methods();
2747 for(int i = 0; i < method_array->length(); i++) {
2748 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2749 }
2750 }
2751 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2752 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2753 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2754 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2755 if (class_loader_data() != NULL) {
2756 st->print(BULLET"class loader data: ");
2757 class_loader_data()->print_value_on(st);
2758 st->cr();
2759 }
2760 st->print(BULLET"protection domain: "); ((InstanceKlass*)this)->protection_domain()->print_value_on(st); st->cr();
2761 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2762 st->print(BULLET"signers: "); signers()->print_value_on(st); st->cr();
2763 st->print(BULLET"init_lock: "); ((oop)init_lock())->print_value_on(st); st->cr();
2764 if (source_file_name() != NULL) {
2765 st->print(BULLET"source file: ");
2766 source_file_name()->print_value_on(st);
2767 st->cr();
2768 }
2769 if (source_debug_extension() != NULL) {
2770 st->print(BULLET"source debug extension: ");
2771 st->print("%s", source_debug_extension());
2772 st->cr();
2773 }
2774 st->print(BULLET"annotations: "); annotations()->print_value_on(st); st->cr();
2775 {
2776 ResourceMark rm;
2777 // PreviousVersionInfo objects returned via PreviousVersionWalker
2778 // contain a GrowableArray of handles. We have to clean up the
2779 // GrowableArray _after_ the PreviousVersionWalker destructor
2780 // has destroyed the handles.
2781 {
2782 bool have_pv = false;
2783 PreviousVersionWalker pvw((InstanceKlass*)this);
2784 for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
2785 pv_info != NULL; pv_info = pvw.next_previous_version()) {
2786 if (!have_pv)
2787 st->print(BULLET"previous version: ");
2788 have_pv = true;
2789 pv_info->prev_constant_pool_handle()()->print_value_on(st);
2790 }
2791 if (have_pv) st->cr();
2792 } // pvw is cleaned up
2793 } // rm is cleaned up
2794
2795 if (generic_signature() != NULL) {
2796 st->print(BULLET"generic signature: ");
2797 generic_signature()->print_value_on(st);
2798 st->cr();
2799 }
2800 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2801 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2802 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2803 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2804 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2805 FieldPrinter print_static_field(st);
2806 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2807 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2808 FieldPrinter print_nonstatic_field(st);
2809 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2810
2811 st->print(BULLET"non-static oop maps: ");
2812 OopMapBlock* map = start_of_nonstatic_oop_maps();
2813 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2814 while (map < end_map) {
2815 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2816 map++;
2817 }
2818 st->cr();
2819 }
2820
2821 #endif //PRODUCT
2822
2823 void InstanceKlass::print_value_on(outputStream* st) const {
2824 assert(is_klass(), "must be klass");
2825 name()->print_value_on(st);
2826 }
2827
2828 #ifndef PRODUCT
2829
2830 void FieldPrinter::do_field(fieldDescriptor* fd) {
2831 _st->print(BULLET);
2832 if (_obj == NULL) {
2833 fd->print_on(_st);
2834 _st->cr();
2835 } else {
2836 fd->print_on_for(_st, _obj);
2837 _st->cr();
2838 }
2839 }
2840
2841
2842 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2843 Klass::oop_print_on(obj, st);
2844
2845 if (this == SystemDictionary::String_klass()) {
2846 typeArrayOop value = java_lang_String::value(obj);
2847 juint offset = java_lang_String::offset(obj);
2848 juint length = java_lang_String::length(obj);
2849 if (value != NULL &&
2850 value->is_typeArray() &&
2851 offset <= (juint) value->length() &&
2852 offset + length <= (juint) value->length()) {
2853 st->print(BULLET"string: ");
2854 Handle h_obj(obj);
2855 java_lang_String::print(h_obj, st);
2856 st->cr();
2857 if (!WizardMode) return; // that is enough
2858 }
2859 }
2860
2861 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2862 FieldPrinter print_field(st, obj);
2863 do_nonstatic_fields(&print_field);
2864
2865 if (this == SystemDictionary::Class_klass()) {
2866 st->print(BULLET"signature: ");
2867 java_lang_Class::print_signature(obj, st);
2868 st->cr();
2869 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2870 st->print(BULLET"fake entry for mirror: ");
2871 mirrored_klass->print_value_on_maybe_null(st);
2872 st->cr();
2873 st->print(BULLET"fake entry resolved_constructor: ");
2874 Method* ctor = java_lang_Class::resolved_constructor(obj);
2875 ctor->print_value_on_maybe_null(st);
2876 Klass* array_klass = java_lang_Class::array_klass(obj);
2877 st->cr();
2878 st->print(BULLET"fake entry for array: ");
2879 array_klass->print_value_on_maybe_null(st);
2880 st->cr();
2881 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2882 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2883 Klass* real_klass = java_lang_Class::as_Klass(obj);
2884 if (real_klass != NULL && real_klass->oop_is_instance()) {
2885 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2886 }
2887 } else if (this == SystemDictionary::MethodType_klass()) {
2888 st->print(BULLET"signature: ");
2889 java_lang_invoke_MethodType::print_signature(obj, st);
2890 st->cr();
2891 }
2892 }
2893
2894 #endif //PRODUCT
2895
2896 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2897 st->print("a ");
2898 name()->print_value_on(st);
2899 obj->print_address_on(st);
2900 if (this == SystemDictionary::String_klass()
2901 && java_lang_String::value(obj) != NULL) {
2902 ResourceMark rm;
2903 int len = java_lang_String::length(obj);
2904 int plen = (len < 24 ? len : 12);
2905 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2906 st->print(" = \"%s\"", str);
2907 if (len > plen)
2908 st->print("...[%d]", len);
2909 } else if (this == SystemDictionary::Class_klass()) {
2910 Klass* k = java_lang_Class::as_Klass(obj);
2911 st->print(" = ");
2912 if (k != NULL) {
2913 k->print_value_on(st);
2914 } else {
2915 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2916 st->print("%s", tname ? tname : "type?");
2917 }
2918 } else if (this == SystemDictionary::MethodType_klass()) {
2919 st->print(" = ");
2920 java_lang_invoke_MethodType::print_signature(obj, st);
2921 } else if (java_lang_boxing_object::is_instance(obj)) {
2922 st->print(" = ");
2923 java_lang_boxing_object::print(obj, st);
2924 } else if (this == SystemDictionary::LambdaForm_klass()) {
2925 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2926 if (vmentry != NULL) {
2927 st->print(" => ");
2928 vmentry->print_value_on(st);
2929 }
2930 } else if (this == SystemDictionary::MemberName_klass()) {
2931 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2932 if (vmtarget != NULL) {
2933 st->print(" = ");
2934 vmtarget->print_value_on(st);
2935 } else {
2936 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2937 st->print(".");
2938 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2939 }
2940 }
2941 }
2942
2943 const char* InstanceKlass::internal_name() const {
2944 return external_name();
2945 }
2946
2947 // Verification
2948
2949 class VerifyFieldClosure: public OopClosure {
2950 protected:
2951 template <class T> void do_oop_work(T* p) {
2952 oop obj = oopDesc::load_decode_heap_oop(p);
2953 if (!obj->is_oop_or_null()) {
2954 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2955 Universe::print();
2956 guarantee(false, "boom");
2957 }
2958 }
2959 public:
2960 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2961 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2962 };
2963
2964 void InstanceKlass::verify_on(outputStream* st) {
2965 Klass::verify_on(st);
2966 Thread *thread = Thread::current();
2967
2968 #ifndef PRODUCT
2969 // Avoid redundant verifies
2970 if (_verify_count == Universe::verify_count()) return;
2971 _verify_count = Universe::verify_count();
2972 #endif
2973 // Verify that klass is present in SystemDictionary
2974 if (is_loaded() && !is_anonymous()) {
2975 Symbol* h_name = name();
2976 SystemDictionary::verify_obj_klass_present(h_name, class_loader_data());
2977 }
2978
2979 // Verify static fields
2980 VerifyFieldClosure blk;
2981
2982 // Verify vtables
2983 if (is_linked()) {
2984 ResourceMark rm(thread);
2985 // $$$ This used to be done only for m/s collections. Doing it
2986 // always seemed a valid generalization. (DLD -- 6/00)
2987 vtable()->verify(st);
2988 }
2989
2990 // Verify first subklass
2991 if (subklass_oop() != NULL) {
2992 guarantee(subklass_oop()->is_metadata(), "should be in metaspace");
2993 guarantee(subklass_oop()->is_klass(), "should be klass");
2994 }
2995
2996 // Verify siblings
2997 Klass* super = this->super();
2998 Klass* sib = next_sibling();
2999 if (sib != NULL) {
3000 if (sib == this) {
3001 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3002 }
3003
3004 guarantee(sib->is_metadata(), "should be in metaspace");
3005 guarantee(sib->is_klass(), "should be klass");
3006 guarantee(sib->super() == super, "siblings should have same superklass");
3007 }
3008
3009 // Verify implementor fields
3010 Klass* im = implementor();
3011 if (im != NULL) {
3012 guarantee(is_interface(), "only interfaces should have implementor set");
3013 guarantee(im->is_klass(), "should be klass");
3014 guarantee(!im->is_interface() || im == this,
3015 "implementors cannot be interfaces");
3016 }
3017
3018 // Verify local interfaces
3019 if (local_interfaces()) {
3020 Array<Klass*>* local_interfaces = this->local_interfaces();
3021 for (int j = 0; j < local_interfaces->length(); j++) {
3022 Klass* e = local_interfaces->at(j);
3023 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3024 }
3025 }
3026
3027 // Verify transitive interfaces
3028 if (transitive_interfaces() != NULL) {
3029 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3030 for (int j = 0; j < transitive_interfaces->length(); j++) {
3031 Klass* e = transitive_interfaces->at(j);
3032 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3033 }
3034 }
3035
3036 // Verify methods
3037 if (methods() != NULL) {
3038 Array<Method*>* methods = this->methods();
3039 for (int j = 0; j < methods->length(); j++) {
3040 guarantee(methods->at(j)->is_metadata(), "should be in metaspace");
3041 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3042 }
3043 for (int j = 0; j < methods->length() - 1; j++) {
3044 Method* m1 = methods->at(j);
3045 Method* m2 = methods->at(j + 1);
3046 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3047 }
3048 }
3049
3050 // Verify method ordering
3051 if (method_ordering() != NULL) {
3052 Array<int>* method_ordering = this->method_ordering();
3053 int length = method_ordering->length();
3054 if (JvmtiExport::can_maintain_original_method_order() ||
3055 (UseSharedSpaces && length != 0)) {
3056 guarantee(length == methods()->length(), "invalid method ordering length");
3057 jlong sum = 0;
3058 for (int j = 0; j < length; j++) {
3059 int original_index = method_ordering->at(j);
3060 guarantee(original_index >= 0, "invalid method ordering index");
3061 guarantee(original_index < length, "invalid method ordering index");
3062 sum += original_index;
3063 }
3064 // Verify sum of indices 0,1,...,length-1
3065 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3066 } else {
3067 guarantee(length == 0, "invalid method ordering length");
3068 }
3069 }
3070
3071 // Verify JNI static field identifiers
3072 if (jni_ids() != NULL) {
3073 jni_ids()->verify(this);
3074 }
3075
3076 // Verify other fields
3077 if (array_klasses() != NULL) {
3078 guarantee(array_klasses()->is_metadata(), "should be in metaspace");
3079 guarantee(array_klasses()->is_klass(), "should be klass");
3080 }
3081 if (constants() != NULL) {
3082 guarantee(constants()->is_metadata(), "should be in metaspace");
3083 guarantee(constants()->is_constantPool(), "should be constant pool");
3084 }
3085 if (protection_domain() != NULL) {
3086 guarantee(protection_domain()->is_oop(), "should be oop");
3087 }
3088 if (host_klass() != NULL) {
3089 guarantee(host_klass()->is_metadata(), "should be in metaspace");
3090 guarantee(host_klass()->is_klass(), "should be klass");
3091 }
3092 if (signers() != NULL) {
3093 guarantee(signers()->is_objArray(), "should be obj array");
3094 }
3095 }
3096
3097 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3098 Klass::oop_verify_on(obj, st);
3099 VerifyFieldClosure blk;
3100 obj->oop_iterate_no_header(&blk);
3101 }
3102
3103
3104 // JNIid class for jfieldIDs only
3105 // Note to reviewers:
3106 // These JNI functions are just moved over to column 1 and not changed
3107 // in the compressed oops workspace.
3108 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3109 _holder = holder;
3110 _offset = offset;
3111 _next = next;
3112 debug_only(_is_static_field_id = false;)
3113 }
3114
3115
3116 JNIid* JNIid::find(int offset) {
3117 JNIid* current = this;
3118 while (current != NULL) {
3119 if (current->offset() == offset) return current;
3120 current = current->next();
3121 }
3122 return NULL;
3123 }
3124
3125 void JNIid::deallocate(JNIid* current) {
3126 while (current != NULL) {
3127 JNIid* next = current->next();
3128 delete current;
3129 current = next;
3130 }
3131 }
3132
3133
3134 void JNIid::verify(Klass* holder) {
3135 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3136 int end_field_offset;
3137 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3138
3139 JNIid* current = this;
3140 while (current != NULL) {
3141 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3142 #ifdef ASSERT
3143 int o = current->offset();
3144 if (current->is_static_field_id()) {
3145 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3146 }
3147 #endif
3148 current = current->next();
3149 }
3150 }
3151
3152
3153 #ifdef ASSERT
3154 void InstanceKlass::set_init_state(ClassState state) {
3155 bool good_state = is_shared() ? (_init_state <= state)
3156 : (_init_state < state);
3157 assert(good_state || state == allocated, "illegal state transition");
3158 _init_state = (u1)state;
3159 }
3160 #endif
3161
3162
3163 // RedefineClasses() support for previous versions:
3164
3165 // Purge previous versions
3166 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3167 if (ik->previous_versions() != NULL) {
3168 // This klass has previous versions so see what we can cleanup
3169 // while it is safe to do so.
3170
3171 int deleted_count = 0; // leave debugging breadcrumbs
3172 int live_count = 0;
3173 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3174 ClassLoaderData::the_null_class_loader_data() :
3175 ik->class_loader_data();
3176
3177 // RC_TRACE macro has an embedded ResourceMark
3178 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3179 ik->external_name(), ik->previous_versions()->length()));
3180
3181 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3182 // check the previous versions array
3183 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3184 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3185 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3186
3187 ConstantPool* pvcp = cp_ref;
3188 if (!pvcp->on_stack()) {
3189 // If the constant pool isn't on stack, none of the methods
3190 // are executing. Delete all the methods, the constant pool and
3191 // and this previous version node.
3192 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3193 if (method_refs != NULL) {
3194 for (int j = method_refs->length() - 1; j >= 0; j--) {
3195 Method* method = method_refs->at(j);
3196 assert(method != NULL, "method ref was unexpectedly cleared");
3197 method_refs->remove_at(j);
3198 // method will be freed with associated class.
3199 }
3200 }
3201 // Remove the constant pool
3202 delete pv_node;
3203 // Since we are traversing the array backwards, we don't have to
3204 // do anything special with the index.
3205 ik->previous_versions()->remove_at(i);
3206 deleted_count++;
3207 continue;
3208 } else {
3209 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3210 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3211 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3212 live_count++;
3213 }
3214
3215 // At least one method is live in this previous version, clean out
3216 // the others or mark them as obsolete.
3217 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3218 if (method_refs != NULL) {
3219 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3220 method_refs->length()));
3221 for (int j = method_refs->length() - 1; j >= 0; j--) {
3222 Method* method = method_refs->at(j);
3223 assert(method != NULL, "method ref was unexpectedly cleared");
3224
3225 // Remove the emcp method if it's not executing
3226 // If it's been made obsolete by a redefinition of a non-emcp
3227 // method, mark it as obsolete but leave it to clean up later.
3228 if (!method->on_stack()) {
3229 method_refs->remove_at(j);
3230 } else if (emcp_method_count == 0) {
3231 method->set_is_obsolete();
3232 } else {
3233 // RC_TRACE macro has an embedded ResourceMark
3234 RC_TRACE(0x00000200,
3235 ("purge: %s(%s): prev method @%d in version @%d is alive",
3236 method->name()->as_C_string(),
3237 method->signature()->as_C_string(), j, i));
3238 }
3239 }
3240 }
3241 }
3242 assert(ik->previous_versions()->length() == live_count, "sanity check");
3243 RC_TRACE(0x00000200,
3244 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3245 deleted_count));
3246 }
3247 }
3248
3249 // External interface for use during class unloading.
3250 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3251 // Call with >0 emcp methods since they are not currently being redefined.
3252 purge_previous_versions_internal(ik, 1);
3253 }
3254
3255
3256 // Potentially add an information node that contains pointers to the
3257 // interesting parts of the previous version of the_class.
3258 // This is also where we clean out any unused references.
3259 // Note that while we delete nodes from the _previous_versions
3260 // array, we never delete the array itself until the klass is
3261 // unloaded. The has_been_redefined() query depends on that fact.
3262 //
3263 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3264 BitMap* emcp_methods, int emcp_method_count) {
3265 assert(Thread::current()->is_VM_thread(),
3266 "only VMThread can add previous versions");
3267
3268 if (_previous_versions == NULL) {
3269 // This is the first previous version so make some space.
3270 // Start with 2 elements under the assumption that the class
3271 // won't be redefined much.
3272 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3273 GrowableArray<PreviousVersionNode *>(2, true);
3274 }
3275
3276 ConstantPool* cp_ref = ikh->constants();
3277
3278 // RC_TRACE macro has an embedded ResourceMark
3279 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3280 "on_stack=%d",
3281 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3282 cp_ref->on_stack()));
3283
3284 // If the constant pool for this previous version of the class
3285 // is not marked as being on the stack, then none of the methods
3286 // in this previous version of the class are on the stack so
3287 // we don't need to create a new PreviousVersionNode. However,
3288 // we still need to examine older previous versions below.
3289 Array<Method*>* old_methods = ikh->methods();
3290
3291 if (cp_ref->on_stack()) {
3292 PreviousVersionNode * pv_node = NULL;
3293 if (emcp_method_count == 0) {
3294 // non-shared ConstantPool gets a reference
3295 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), NULL);
3296 RC_TRACE(0x00000400,
3297 ("add: all methods are obsolete; flushing any EMCP refs"));
3298 } else {
3299 int local_count = 0;
3300 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3301 GrowableArray<Method*>(emcp_method_count, true);
3302 for (int i = 0; i < old_methods->length(); i++) {
3303 if (emcp_methods->at(i)) {
3304 // this old method is EMCP. Save it only if it's on the stack
3305 Method* old_method = old_methods->at(i);
3306 if (old_method->on_stack()) {
3307 method_refs->append(old_method);
3308 }
3309 if (++local_count >= emcp_method_count) {
3310 // no more EMCP methods so bail out now
3311 break;
3312 }
3313 }
3314 }
3315 // non-shared ConstantPool gets a reference
3316 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), method_refs);
3317 }
3318 // append new previous version.
3319 _previous_versions->append(pv_node);
3320 }
3321
3322 // Since the caller is the VMThread and we are at a safepoint, this
3323 // is a good time to clear out unused references.
3324
3325 RC_TRACE(0x00000400, ("add: previous version length=%d",
3326 _previous_versions->length()));
3327
3328 // Purge previous versions not executing on the stack
3329 purge_previous_versions_internal(this, emcp_method_count);
3330
3331 int obsolete_method_count = old_methods->length() - emcp_method_count;
3332
3333 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3334 _previous_versions->length() > 0) {
3335 // We have a mix of obsolete and EMCP methods so we have to
3336 // clear out any matching EMCP method entries the hard way.
3337 int local_count = 0;
3338 for (int i = 0; i < old_methods->length(); i++) {
3339 if (!emcp_methods->at(i)) {
3340 // only obsolete methods are interesting
3341 Method* old_method = old_methods->at(i);
3342 Symbol* m_name = old_method->name();
3343 Symbol* m_signature = old_method->signature();
3344
3345 // we might not have added the last entry
3346 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3347 // check the previous versions array for non executing obsolete methods
3348 PreviousVersionNode * pv_node = _previous_versions->at(j);
3349
3350 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3351 if (method_refs == NULL) {
3352 // We have run into a PreviousVersion generation where
3353 // all methods were made obsolete during that generation's
3354 // RedefineClasses() operation. At the time of that
3355 // operation, all EMCP methods were flushed so we don't
3356 // have to go back any further.
3357 //
3358 // A NULL method_refs is different than an empty method_refs.
3359 // We cannot infer any optimizations about older generations
3360 // from an empty method_refs for the current generation.
3361 break;
3362 }
3363
3364 for (int k = method_refs->length() - 1; k >= 0; k--) {
3365 Method* method = method_refs->at(k);
3366
3367 if (!method->is_obsolete() &&
3368 method->name() == m_name &&
3369 method->signature() == m_signature) {
3370 // The current RedefineClasses() call has made all EMCP
3371 // versions of this method obsolete so mark it as obsolete
3372 // and remove the reference.
3373 RC_TRACE(0x00000400,
3374 ("add: %s(%s): flush obsolete method @%d in version @%d",
3375 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3376
3377 method->set_is_obsolete();
3378 // Leave obsolete methods on the previous version list to
3379 // clean up later.
3380 break;
3381 }
3382 }
3383
3384 // The previous loop may not find a matching EMCP method, but
3385 // that doesn't mean that we can optimize and not go any
3386 // further back in the PreviousVersion generations. The EMCP
3387 // method for this generation could have already been deleted,
3388 // but there still may be an older EMCP method that has not
3389 // been deleted.
3390 }
3391
3392 if (++local_count >= obsolete_method_count) {
3393 // no more obsolete methods so bail out now
3394 break;
3395 }
3396 }
3397 }
3398 }
3399 } // end add_previous_version()
3400
3401
3402 // Determine if InstanceKlass has a previous version.
3403 bool InstanceKlass::has_previous_version() const {
3404 return (_previous_versions != NULL && _previous_versions->length() > 0);
3405 } // end has_previous_version()
3406
3407
3408 Method* InstanceKlass::method_with_idnum(int idnum) {
3409 Method* m = NULL;
3410 if (idnum < methods()->length()) {
3411 m = methods()->at(idnum);
3412 }
3413 if (m == NULL || m->method_idnum() != idnum) {
3414 for (int index = 0; index < methods()->length(); ++index) {
3415 m = methods()->at(index);
3416 if (m->method_idnum() == idnum) {
3417 return m;
3418 }
3419 }
3420 }
3421 return m;
3422 }
3423
3424
3425 // Construct a PreviousVersionNode entry for the array hung off
3426 // the InstanceKlass.
3427 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3428 bool prev_cp_is_weak, GrowableArray<Method*>* prev_EMCP_methods) {
3429
3430 _prev_constant_pool = prev_constant_pool;
3431 _prev_cp_is_weak = prev_cp_is_weak;
3432 _prev_EMCP_methods = prev_EMCP_methods;
3433 }
3434
3435
3436 // Destroy a PreviousVersionNode
3437 PreviousVersionNode::~PreviousVersionNode() {
3438 if (_prev_constant_pool != NULL) {
3439 _prev_constant_pool = NULL;
3440 }
3441
3442 if (_prev_EMCP_methods != NULL) {
3443 delete _prev_EMCP_methods;
3444 }
3445 }
3446
3447
3448 // Construct a PreviousVersionInfo entry
3449 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
3450 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
3451 _prev_EMCP_method_handles = NULL;
3452
3453 ConstantPool* cp = pv_node->prev_constant_pool();
3454 assert(cp != NULL, "constant pool ref was unexpectedly cleared");
3455 if (cp == NULL) {
3456 return; // robustness
3457 }
3458
3459 // make the ConstantPool* safe to return
3460 _prev_constant_pool_handle = constantPoolHandle(cp);
3461
3462 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3463 if (method_refs == NULL) {
3464 // the InstanceKlass did not have any EMCP methods
3465 return;
3466 }
3467
3468 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
3469
3470 int n_methods = method_refs->length();
3471 for (int i = 0; i < n_methods; i++) {
3472 Method* method = method_refs->at(i);
3473 assert (method != NULL, "method has been cleared");
3474 if (method == NULL) {
3475 continue; // robustness
3476 }
3477 // make the Method* safe to return
3478 _prev_EMCP_method_handles->append(methodHandle(method));
3479 }
3480 }
3481
3482
3483 // Destroy a PreviousVersionInfo
3484 PreviousVersionInfo::~PreviousVersionInfo() {
3485 // Since _prev_EMCP_method_handles is not C-heap allocated, we
3486 // don't have to delete it.
3487 }
3488
3489
3490 // Construct a helper for walking the previous versions array
3491 PreviousVersionWalker::PreviousVersionWalker(InstanceKlass *ik) {
3492 _previous_versions = ik->previous_versions();
3493 _current_index = 0;
3494 // _hm needs no initialization
3495 _current_p = NULL;
3496 }
3497
3498
3499 // Destroy a PreviousVersionWalker
3500 PreviousVersionWalker::~PreviousVersionWalker() {
3501 // Delete the current info just in case the caller didn't walk to
3502 // the end of the previous versions list. No harm if _current_p is
3503 // already NULL.
3504 delete _current_p;
3505
3506 // When _hm is destroyed, all the Handles returned in
3507 // PreviousVersionInfo objects will be destroyed.
3508 // Also, after this destructor is finished it will be
3509 // safe to delete the GrowableArray allocated in the
3510 // PreviousVersionInfo objects.
3511 }
3512
3513
3514 // Return the interesting information for the next previous version
3515 // of the klass. Returns NULL if there are no more previous versions.
3516 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
3517 if (_previous_versions == NULL) {
3518 // no previous versions so nothing to return
3519 return NULL;
3520 }
3521
3522 delete _current_p; // cleanup the previous info for the caller
3523 _current_p = NULL; // reset to NULL so we don't delete same object twice
3524
3525 int length = _previous_versions->length();
3526
3527 while (_current_index < length) {
3528 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3529 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP, mtClass)
3530 PreviousVersionInfo(pv_node);
3531
3532 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
3533 assert (!cp_h.is_null(), "null cp found in previous version");
3534
3535 // The caller will need to delete pv_info when they are done with it.
3536 _current_p = pv_info;
3537 return pv_info;
3538 }
3539
3540 // all of the underlying nodes' info has been deleted
3541 return NULL;
3542 } // end next_previous_version()