comparison src/share/vm/oops/instanceKlass.cpp @ 0:a61af66fc99e jdk7-b24

Initial load
author duke
date Sat, 01 Dec 2007 00:00:00 +0000
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children 52fed2ec0afb 2c106685d6d0
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-1:000000000000 0:a61af66fc99e
1 /*
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 # include "incls/_precompiled.incl"
26 # include "incls/_instanceKlass.cpp.incl"
27
28 bool instanceKlass::should_be_initialized() const {
29 return !is_initialized();
30 }
31
32 klassVtable* instanceKlass::vtable() const {
33 return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
34 }
35
36 klassItable* instanceKlass::itable() const {
37 return new klassItable(as_klassOop());
38 }
39
40 void instanceKlass::eager_initialize(Thread *thread) {
41 if (!EagerInitialization) return;
42
43 if (this->is_not_initialized()) {
44 // abort if the the class has a class initializer
45 if (this->class_initializer() != NULL) return;
46
47 // abort if it is java.lang.Object (initialization is handled in genesis)
48 klassOop super = this->super();
49 if (super == NULL) return;
50
51 // abort if the super class should be initialized
52 if (!instanceKlass::cast(super)->is_initialized()) return;
53
54 // call body to expose the this pointer
55 instanceKlassHandle this_oop(thread, this->as_klassOop());
56 eager_initialize_impl(this_oop);
57 }
58 }
59
60
61 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
62 EXCEPTION_MARK;
63 ObjectLocker ol(this_oop, THREAD);
64
65 // abort if someone beat us to the initialization
66 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
67
68 ClassState old_state = this_oop->_init_state;
69 link_class_impl(this_oop, true, THREAD);
70 if (HAS_PENDING_EXCEPTION) {
71 CLEAR_PENDING_EXCEPTION;
72 // Abort if linking the class throws an exception.
73
74 // Use a test to avoid redundantly resetting the state if there's
75 // no change. Set_init_state() asserts that state changes make
76 // progress, whereas here we might just be spinning in place.
77 if( old_state != this_oop->_init_state )
78 this_oop->set_init_state (old_state);
79 } else {
80 // linking successfull, mark class as initialized
81 this_oop->set_init_state (fully_initialized);
82 // trace
83 if (TraceClassInitialization) {
84 ResourceMark rm(THREAD);
85 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
86 }
87 }
88 }
89
90
91 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
92 // process. The step comments refers to the procedure described in that section.
93 // Note: implementation moved to static method to expose the this pointer.
94 void instanceKlass::initialize(TRAPS) {
95 if (this->should_be_initialized()) {
96 HandleMark hm(THREAD);
97 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
98 initialize_impl(this_oop, CHECK);
99 // Note: at this point the class may be initialized
100 // OR it may be in the state of being initialized
101 // in case of recursive initialization!
102 } else {
103 assert(is_initialized(), "sanity check");
104 }
105 }
106
107
108 bool instanceKlass::verify_code(
109 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
110 // 1) Verify the bytecodes
111 Verifier::Mode mode =
112 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
113 return Verifier::verify(this_oop, mode, CHECK_false);
114 }
115
116
117 // Used exclusively by the shared spaces dump mechanism to prevent
118 // classes mapped into the shared regions in new VMs from appearing linked.
119
120 void instanceKlass::unlink_class() {
121 assert(is_linked(), "must be linked");
122 _init_state = loaded;
123 }
124
125 void instanceKlass::link_class(TRAPS) {
126 assert(is_loaded(), "must be loaded");
127 if (!is_linked()) {
128 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
129 link_class_impl(this_oop, true, CHECK);
130 }
131 }
132
133 // Called to verify that a class can link during initialization, without
134 // throwing a VerifyError.
135 bool instanceKlass::link_class_or_fail(TRAPS) {
136 assert(is_loaded(), "must be loaded");
137 if (!is_linked()) {
138 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
139 link_class_impl(this_oop, false, CHECK_false);
140 }
141 return is_linked();
142 }
143
144 bool instanceKlass::link_class_impl(
145 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
146 // check for error state
147 if (this_oop->is_in_error_state()) {
148 ResourceMark rm(THREAD);
149 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
150 this_oop->external_name(), false);
151 }
152 // return if already verified
153 if (this_oop->is_linked()) {
154 return true;
155 }
156
157 // Timing
158 // timer handles recursion
159 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
160 JavaThread* jt = (JavaThread*)THREAD;
161 PerfTraceTimedEvent vmtimer(ClassLoader::perf_class_link_time(),
162 ClassLoader::perf_classes_linked(),
163 jt->get_thread_stat()->class_link_recursion_count_addr());
164
165 // link super class before linking this class
166 instanceKlassHandle super(THREAD, this_oop->super());
167 if (super.not_null()) {
168 if (super->is_interface()) { // check if super class is an interface
169 ResourceMark rm(THREAD);
170 Exceptions::fthrow(
171 THREAD_AND_LOCATION,
172 vmSymbolHandles::java_lang_IncompatibleClassChangeError(),
173 "class %s has interface %s as super class",
174 this_oop->external_name(),
175 super->external_name()
176 );
177 return false;
178 }
179
180 link_class_impl(super, throw_verifyerror, CHECK_false);
181 }
182
183 // link all interfaces implemented by this class before linking this class
184 objArrayHandle interfaces (THREAD, this_oop->local_interfaces());
185 int num_interfaces = interfaces->length();
186 for (int index = 0; index < num_interfaces; index++) {
187 HandleMark hm(THREAD);
188 instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index)));
189 link_class_impl(ih, throw_verifyerror, CHECK_false);
190 }
191
192 // in case the class is linked in the process of linking its superclasses
193 if (this_oop->is_linked()) {
194 return true;
195 }
196
197 // verification & rewriting
198 {
199 ObjectLocker ol(this_oop, THREAD);
200 // rewritten will have been set if loader constraint error found
201 // on an earlier link attempt
202 // don't verify or rewrite if already rewritten
203 if (!this_oop->is_linked()) {
204 if (!this_oop->is_rewritten()) {
205 {
206 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
207 JavaThread* jt = (JavaThread*)THREAD;
208 // Timer includes any side effects of class verification (resolution,
209 // etc), but not recursive entry into verify_code().
210 PerfTraceTime timer(ClassLoader::perf_class_verify_time(),
211 jt->get_thread_stat()->class_verify_recursion_count_addr());
212 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
213 if (!verify_ok) {
214 return false;
215 }
216 }
217
218 // Just in case a side-effect of verify linked this class already
219 // (which can sometimes happen since the verifier loads classes
220 // using custom class loaders, which are free to initialize things)
221 if (this_oop->is_linked()) {
222 return true;
223 }
224
225 // also sets rewritten
226 this_oop->rewrite_class(CHECK_false);
227 }
228
229 // Initialize the vtable and interface table after
230 // methods have been rewritten since rewrite may
231 // fabricate new methodOops.
232 // also does loader constraint checking
233 if (!this_oop()->is_shared()) {
234 ResourceMark rm(THREAD);
235 this_oop->vtable()->initialize_vtable(true, CHECK_false);
236 this_oop->itable()->initialize_itable(true, CHECK_false);
237 }
238 #ifdef ASSERT
239 else {
240 ResourceMark rm(THREAD);
241 this_oop->vtable()->verify(tty, true);
242 // In case itable verification is ever added.
243 // this_oop->itable()->verify(tty, true);
244 }
245 #endif
246 this_oop->set_init_state(linked);
247 if (JvmtiExport::should_post_class_prepare()) {
248 Thread *thread = THREAD;
249 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
250 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
251 }
252 }
253 }
254 return true;
255 }
256
257
258 // Rewrite the byte codes of all of the methods of a class.
259 // Three cases:
260 // During the link of a newly loaded class.
261 // During the preloading of classes to be written to the shared spaces.
262 // - Rewrite the methods and update the method entry points.
263 //
264 // During the link of a class in the shared spaces.
265 // - The methods were already rewritten, update the metho entry points.
266 //
267 // The rewriter must be called exactly once. Rewriting must happen after
268 // verification but before the first method of the class is executed.
269
270 void instanceKlass::rewrite_class(TRAPS) {
271 assert(is_loaded(), "must be loaded");
272 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
273 if (this_oop->is_rewritten()) {
274 assert(this_oop()->is_shared(), "rewriting an unshared class?");
275 return;
276 }
277 Rewriter::rewrite(this_oop, CHECK); // No exception can happen here
278 this_oop->set_rewritten();
279 }
280
281
282 void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
283 // Make sure klass is linked (verified) before initialization
284 // A class could already be verified, since it has been reflected upon.
285 this_oop->link_class(CHECK);
286
287 // refer to the JVM book page 47 for description of steps
288 // Step 1
289 { ObjectLocker ol(this_oop, THREAD);
290
291 Thread *self = THREAD; // it's passed the current thread
292
293 // Step 2
294 // If we were to use wait() instead of waitInterruptibly() then
295 // we might end up throwing IE from link/symbol resolution sites
296 // that aren't expected to throw. This would wreak havoc. See 6320309.
297 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
298 ol.waitUninterruptibly(CHECK);
299 }
300
301 // Step 3
302 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self))
303 return;
304
305 // Step 4
306 if (this_oop->is_initialized())
307 return;
308
309 // Step 5
310 if (this_oop->is_in_error_state()) {
311 ResourceMark rm(THREAD);
312 const char* desc = "Could not initialize class ";
313 const char* className = this_oop->external_name();
314 size_t msglen = strlen(desc) + strlen(className) + 1;
315 char* message = NEW_C_HEAP_ARRAY(char, msglen);
316 if (NULL == message) {
317 // Out of memory: can't create detailed error message
318 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
319 } else {
320 jio_snprintf(message, msglen, "%s%s", desc, className);
321 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
322 }
323 }
324
325 // Step 6
326 this_oop->set_init_state(being_initialized);
327 this_oop->set_init_thread(self);
328 }
329
330 // Step 7
331 klassOop super_klass = this_oop->super();
332 if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) {
333 Klass::cast(super_klass)->initialize(THREAD);
334
335 if (HAS_PENDING_EXCEPTION) {
336 Handle e(THREAD, PENDING_EXCEPTION);
337 CLEAR_PENDING_EXCEPTION;
338 {
339 EXCEPTION_MARK;
340 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
341 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
342 }
343 THROW_OOP(e());
344 }
345 }
346
347 // Step 8
348 {
349 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
350 JavaThread* jt = (JavaThread*)THREAD;
351 // Timer includes any side effects of class initialization (resolution,
352 // etc), but not recursive entry into call_class_initializer().
353 PerfTraceTimedEvent timer(ClassLoader::perf_class_init_time(),
354 ClassLoader::perf_classes_inited(),
355 jt->get_thread_stat()->class_init_recursion_count_addr());
356 this_oop->call_class_initializer(THREAD);
357 }
358
359 // Step 9
360 if (!HAS_PENDING_EXCEPTION) {
361 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
362 { ResourceMark rm(THREAD);
363 debug_only(this_oop->vtable()->verify(tty, true);)
364 }
365 }
366 else {
367 // Step 10 and 11
368 Handle e(THREAD, PENDING_EXCEPTION);
369 CLEAR_PENDING_EXCEPTION;
370 {
371 EXCEPTION_MARK;
372 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
373 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
374 }
375 if (e->is_a(SystemDictionary::error_klass())) {
376 THROW_OOP(e());
377 } else {
378 JavaCallArguments args(e);
379 THROW_ARG(vmSymbolHandles::java_lang_ExceptionInInitializerError(),
380 vmSymbolHandles::throwable_void_signature(),
381 &args);
382 }
383 }
384 }
385
386
387 // Note: implementation moved to static method to expose the this pointer.
388 void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
389 instanceKlassHandle kh(THREAD, this->as_klassOop());
390 set_initialization_state_and_notify_impl(kh, state, CHECK);
391 }
392
393 void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
394 ObjectLocker ol(this_oop, THREAD);
395 this_oop->set_init_state(state);
396 ol.notify_all(CHECK);
397 }
398
399 void instanceKlass::add_implementor(klassOop k) {
400 assert(Compile_lock->owned_by_self(), "");
401 // Filter out my subinterfaces.
402 // (Note: Interfaces are never on the subklass list.)
403 if (instanceKlass::cast(k)->is_interface()) return;
404
405 // Filter out subclasses whose supers already implement me.
406 // (Note: CHA must walk subclasses of direct implementors
407 // in order to locate indirect implementors.)
408 klassOop sk = instanceKlass::cast(k)->super();
409 if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop()))
410 // We only need to check one immediate superclass, since the
411 // implements_interface query looks at transitive_interfaces.
412 // Any supers of the super have the same (or fewer) transitive_interfaces.
413 return;
414
415 // Update number of implementors
416 int i = _nof_implementors++;
417
418 // Record this implementor, if there are not too many already
419 if (i < implementors_limit) {
420 assert(_implementors[i] == NULL, "should be exactly one implementor");
421 oop_store_without_check((oop*)&_implementors[i], k);
422 } else if (i == implementors_limit) {
423 // clear out the list on first overflow
424 for (int i2 = 0; i2 < implementors_limit; i2++)
425 oop_store_without_check((oop*)&_implementors[i2], NULL);
426 }
427
428 // The implementor also implements the transitive_interfaces
429 for (int index = 0; index < local_interfaces()->length(); index++) {
430 instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k);
431 }
432 }
433
434 void instanceKlass::init_implementor() {
435 for (int i = 0; i < implementors_limit; i++)
436 oop_store_without_check((oop*)&_implementors[i], NULL);
437 _nof_implementors = 0;
438 }
439
440
441 void instanceKlass::process_interfaces(Thread *thread) {
442 // link this class into the implementors list of every interface it implements
443 KlassHandle this_as_oop (thread, this->as_klassOop());
444 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
445 assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass");
446 instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i)));
447 assert(interf->is_interface(), "expected interface");
448 interf->add_implementor(this_as_oop());
449 }
450 }
451
452 bool instanceKlass::can_be_primary_super_slow() const {
453 if (is_interface())
454 return false;
455 else
456 return Klass::can_be_primary_super_slow();
457 }
458
459 objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) {
460 // The secondaries are the implemented interfaces.
461 instanceKlass* ik = instanceKlass::cast(as_klassOop());
462 objArrayHandle interfaces (THREAD, ik->transitive_interfaces());
463 int num_secondaries = num_extra_slots + interfaces->length();
464 if (num_secondaries == 0) {
465 return Universe::the_empty_system_obj_array();
466 } else if (num_extra_slots == 0) {
467 return interfaces();
468 } else {
469 // a mix of both
470 objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL);
471 for (int i = 0; i < interfaces->length(); i++) {
472 secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i));
473 }
474 return secondaries;
475 }
476 }
477
478 bool instanceKlass::compute_is_subtype_of(klassOop k) {
479 if (Klass::cast(k)->is_interface()) {
480 return implements_interface(k);
481 } else {
482 return Klass::compute_is_subtype_of(k);
483 }
484 }
485
486 bool instanceKlass::implements_interface(klassOop k) const {
487 if (as_klassOop() == k) return true;
488 assert(Klass::cast(k)->is_interface(), "should be an interface class");
489 for (int i = 0; i < transitive_interfaces()->length(); i++) {
490 if (transitive_interfaces()->obj_at(i) == k) {
491 return true;
492 }
493 }
494 return false;
495 }
496
497 objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) {
498 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
499 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
500 THROW_OOP_0(Universe::out_of_memory_error_array_size());
501 }
502 int size = objArrayOopDesc::object_size(length);
503 klassOop ak = array_klass(n, CHECK_NULL);
504 KlassHandle h_ak (THREAD, ak);
505 objArrayOop o =
506 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
507 return o;
508 }
509
510 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) {
511 if (TraceFinalizerRegistration) {
512 tty->print("Registered ");
513 i->print_value_on(tty);
514 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
515 }
516 instanceHandle h_i(THREAD, i);
517 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
518 JavaValue result(T_VOID);
519 JavaCallArguments args(h_i);
520 methodHandle mh (THREAD, Universe::finalizer_register_method());
521 JavaCalls::call(&result, mh, &args, CHECK_NULL);
522 return h_i();
523 }
524
525 instanceOop instanceKlass::allocate_instance(TRAPS) {
526 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
527 int size = size_helper(); // Query before forming handle.
528
529 KlassHandle h_k(THREAD, as_klassOop());
530
531 instanceOop i;
532
533 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
534 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
535 i = register_finalizer(i, CHECK_NULL);
536 }
537 return i;
538 }
539
540 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) {
541 // Finalizer registration occurs in the Object.<init> constructor
542 // and constructors normally aren't run when allocating perm
543 // instances so simply disallow finalizable perm objects. This can
544 // be relaxed if a need for it is found.
545 assert(!has_finalizer(), "perm objects not allowed to have finalizers");
546 int size = size_helper(); // Query before forming handle.
547 KlassHandle h_k(THREAD, as_klassOop());
548 instanceOop i = (instanceOop)
549 CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
550 return i;
551 }
552
553 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
554 if (is_interface() || is_abstract()) {
555 ResourceMark rm(THREAD);
556 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
557 : vmSymbols::java_lang_InstantiationException(), external_name());
558 }
559 if (as_klassOop() == SystemDictionary::class_klass()) {
560 ResourceMark rm(THREAD);
561 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
562 : vmSymbols::java_lang_IllegalAccessException(), external_name());
563 }
564 }
565
566 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
567 instanceKlassHandle this_oop(THREAD, as_klassOop());
568 return array_klass_impl(this_oop, or_null, n, THREAD);
569 }
570
571 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
572 if (this_oop->array_klasses() == NULL) {
573 if (or_null) return NULL;
574
575 ResourceMark rm;
576 JavaThread *jt = (JavaThread *)THREAD;
577 {
578 // Atomic creation of array_klasses
579 MutexLocker mc(Compile_lock, THREAD); // for vtables
580 MutexLocker ma(MultiArray_lock, THREAD);
581
582 // Check if update has already taken place
583 if (this_oop->array_klasses() == NULL) {
584 objArrayKlassKlass* oakk =
585 (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
586
587 klassOop k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL);
588 this_oop->set_array_klasses(k);
589 }
590 }
591 }
592 // _this will always be set at this point
593 objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part();
594 if (or_null) {
595 return oak->array_klass_or_null(n);
596 }
597 return oak->array_klass(n, CHECK_NULL);
598 }
599
600 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
601 return array_klass_impl(or_null, 1, THREAD);
602 }
603
604 void instanceKlass::call_class_initializer(TRAPS) {
605 instanceKlassHandle ik (THREAD, as_klassOop());
606 call_class_initializer_impl(ik, THREAD);
607 }
608
609 static int call_class_initializer_impl_counter = 0; // for debugging
610
611 methodOop instanceKlass::class_initializer() {
612 return find_method(vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
613 }
614
615 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
616 methodHandle h_method(THREAD, this_oop->class_initializer());
617 assert(!this_oop->is_initialized(), "we cannot initialize twice");
618 if (TraceClassInitialization) {
619 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
620 this_oop->name()->print_value();
621 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
622 }
623 if (h_method() != NULL) {
624 JavaCallArguments args; // No arguments
625 JavaValue result(T_VOID);
626 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
627 }
628 }
629
630
631 void instanceKlass::mask_for(methodHandle method, int bci,
632 InterpreterOopMap* entry_for) {
633 // Dirty read, then double-check under a lock.
634 if (_oop_map_cache == NULL) {
635 // Otherwise, allocate a new one.
636 MutexLocker x(OopMapCacheAlloc_lock);
637 // First time use. Allocate a cache in C heap
638 if (_oop_map_cache == NULL) {
639 _oop_map_cache = new OopMapCache();
640 }
641 }
642 // _oop_map_cache is constant after init; lookup below does is own locking.
643 _oop_map_cache->lookup(method, bci, entry_for);
644 }
645
646
647 bool instanceKlass::find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
648 const int n = fields()->length();
649 for (int i = 0; i < n; i += next_offset ) {
650 int name_index = fields()->ushort_at(i + name_index_offset);
651 int sig_index = fields()->ushort_at(i + signature_index_offset);
652 symbolOop f_name = constants()->symbol_at(name_index);
653 symbolOop f_sig = constants()->symbol_at(sig_index);
654 if (f_name == name && f_sig == sig) {
655 fd->initialize(as_klassOop(), i);
656 return true;
657 }
658 }
659 return false;
660 }
661
662
663 void instanceKlass::field_names_and_sigs_iterate(OopClosure* closure) {
664 const int n = fields()->length();
665 for (int i = 0; i < n; i += next_offset ) {
666 int name_index = fields()->ushort_at(i + name_index_offset);
667 symbolOop name = constants()->symbol_at(name_index);
668 closure->do_oop((oop*)&name);
669
670 int sig_index = fields()->ushort_at(i + signature_index_offset);
671 symbolOop sig = constants()->symbol_at(sig_index);
672 closure->do_oop((oop*)&sig);
673 }
674 }
675
676
677 klassOop instanceKlass::find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
678 const int n = local_interfaces()->length();
679 for (int i = 0; i < n; i++) {
680 klassOop intf1 = klassOop(local_interfaces()->obj_at(i));
681 assert(Klass::cast(intf1)->is_interface(), "just checking type");
682 // search for field in current interface
683 if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
684 assert(fd->is_static(), "interface field must be static");
685 return intf1;
686 }
687 // search for field in direct superinterfaces
688 klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
689 if (intf2 != NULL) return intf2;
690 }
691 // otherwise field lookup fails
692 return NULL;
693 }
694
695
696 klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
697 // search order according to newest JVM spec (5.4.3.2, p.167).
698 // 1) search for field in current klass
699 if (find_local_field(name, sig, fd)) {
700 return as_klassOop();
701 }
702 // 2) search for field recursively in direct superinterfaces
703 { klassOop intf = find_interface_field(name, sig, fd);
704 if (intf != NULL) return intf;
705 }
706 // 3) apply field lookup recursively if superclass exists
707 { klassOop supr = super();
708 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd);
709 }
710 // 4) otherwise field lookup fails
711 return NULL;
712 }
713
714
715 klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const {
716 // search order according to newest JVM spec (5.4.3.2, p.167).
717 // 1) search for field in current klass
718 if (find_local_field(name, sig, fd)) {
719 if (fd->is_static() == is_static) return as_klassOop();
720 }
721 // 2) search for field recursively in direct superinterfaces
722 if (is_static) {
723 klassOop intf = find_interface_field(name, sig, fd);
724 if (intf != NULL) return intf;
725 }
726 // 3) apply field lookup recursively if superclass exists
727 { klassOop supr = super();
728 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
729 }
730 // 4) otherwise field lookup fails
731 return NULL;
732 }
733
734
735 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
736 int length = fields()->length();
737 for (int i = 0; i < length; i += next_offset) {
738 if (offset_from_fields( i ) == offset) {
739 fd->initialize(as_klassOop(), i);
740 if (fd->is_static() == is_static) return true;
741 }
742 }
743 return false;
744 }
745
746
747 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
748 klassOop klass = as_klassOop();
749 while (klass != NULL) {
750 if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
751 return true;
752 }
753 klass = Klass::cast(klass)->super();
754 }
755 return false;
756 }
757
758
759 void instanceKlass::methods_do(void f(methodOop method)) {
760 int len = methods()->length();
761 for (int index = 0; index < len; index++) {
762 methodOop m = methodOop(methods()->obj_at(index));
763 assert(m->is_method(), "must be method");
764 f(m);
765 }
766 }
767
768 void instanceKlass::do_local_static_fields(FieldClosure* cl) {
769 fieldDescriptor fd;
770 int length = fields()->length();
771 for (int i = 0; i < length; i += next_offset) {
772 fd.initialize(as_klassOop(), i);
773 if (fd.is_static()) cl->do_field(&fd);
774 }
775 }
776
777
778 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
779 instanceKlassHandle h_this(THREAD, as_klassOop());
780 do_local_static_fields_impl(h_this, f, CHECK);
781 }
782
783
784 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
785 fieldDescriptor fd;
786 int length = this_oop->fields()->length();
787 for (int i = 0; i < length; i += next_offset) {
788 fd.initialize(this_oop(), i);
789 if (fd.is_static()) { f(&fd, CHECK); } // Do NOT remove {}! (CHECK macro expands into several statements)
790 }
791 }
792
793
794 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
795 fieldDescriptor fd;
796 instanceKlass* super = superklass();
797 if (super != NULL) {
798 super->do_nonstatic_fields(cl);
799 }
800 int length = fields()->length();
801 for (int i = 0; i < length; i += next_offset) {
802 fd.initialize(as_klassOop(), i);
803 if (!(fd.is_static())) cl->do_field(&fd);
804 }
805 }
806
807
808 void instanceKlass::array_klasses_do(void f(klassOop k)) {
809 if (array_klasses() != NULL)
810 arrayKlass::cast(array_klasses())->array_klasses_do(f);
811 }
812
813
814 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
815 f(as_klassOop());
816 array_klasses_do(f);
817 }
818
819 #ifdef ASSERT
820 static int linear_search(objArrayOop methods, symbolOop name, symbolOop signature) {
821 int len = methods->length();
822 for (int index = 0; index < len; index++) {
823 methodOop m = (methodOop)(methods->obj_at(index));
824 assert(m->is_method(), "must be method");
825 if (m->signature() == signature && m->name() == name) {
826 return index;
827 }
828 }
829 return -1;
830 }
831 #endif
832
833 methodOop instanceKlass::find_method(symbolOop name, symbolOop signature) const {
834 return instanceKlass::find_method(methods(), name, signature);
835 }
836
837 methodOop instanceKlass::find_method(objArrayOop methods, symbolOop name, symbolOop signature) {
838 int len = methods->length();
839 // methods are sorted, so do binary search
840 int l = 0;
841 int h = len - 1;
842 while (l <= h) {
843 int mid = (l + h) >> 1;
844 methodOop m = (methodOop)methods->obj_at(mid);
845 assert(m->is_method(), "must be method");
846 int res = m->name()->fast_compare(name);
847 if (res == 0) {
848 // found matching name; do linear search to find matching signature
849 // first, quick check for common case
850 if (m->signature() == signature) return m;
851 // search downwards through overloaded methods
852 int i;
853 for (i = mid - 1; i >= l; i--) {
854 methodOop m = (methodOop)methods->obj_at(i);
855 assert(m->is_method(), "must be method");
856 if (m->name() != name) break;
857 if (m->signature() == signature) return m;
858 }
859 // search upwards
860 for (i = mid + 1; i <= h; i++) {
861 methodOop m = (methodOop)methods->obj_at(i);
862 assert(m->is_method(), "must be method");
863 if (m->name() != name) break;
864 if (m->signature() == signature) return m;
865 }
866 // not found
867 #ifdef ASSERT
868 int index = linear_search(methods, name, signature);
869 if (index != -1) fatal1("binary search bug: should have found entry %d", index);
870 #endif
871 return NULL;
872 } else if (res < 0) {
873 l = mid + 1;
874 } else {
875 h = mid - 1;
876 }
877 }
878 #ifdef ASSERT
879 int index = linear_search(methods, name, signature);
880 if (index != -1) fatal1("binary search bug: should have found entry %d", index);
881 #endif
882 return NULL;
883 }
884
885 methodOop instanceKlass::uncached_lookup_method(symbolOop name, symbolOop signature) const {
886 klassOop klass = as_klassOop();
887 while (klass != NULL) {
888 methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
889 if (method != NULL) return method;
890 klass = instanceKlass::cast(klass)->super();
891 }
892 return NULL;
893 }
894
895 // lookup a method in all the interfaces that this class implements
896 methodOop instanceKlass::lookup_method_in_all_interfaces(symbolOop name,
897 symbolOop signature) const {
898 objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
899 int num_ifs = all_ifs->length();
900 instanceKlass *ik = NULL;
901 for (int i = 0; i < num_ifs; i++) {
902 ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
903 methodOop m = ik->lookup_method(name, signature);
904 if (m != NULL) {
905 return m;
906 }
907 }
908 return NULL;
909 }
910
911 /* jni_id_for_impl for jfieldIds only */
912 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
913 MutexLocker ml(JfieldIdCreation_lock);
914 // Retry lookup after we got the lock
915 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
916 if (probe == NULL) {
917 // Slow case, allocate new static field identifier
918 probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
919 this_oop->set_jni_ids(probe);
920 }
921 return probe;
922 }
923
924
925 /* jni_id_for for jfieldIds only */
926 JNIid* instanceKlass::jni_id_for(int offset) {
927 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
928 if (probe == NULL) {
929 probe = jni_id_for_impl(this->as_klassOop(), offset);
930 }
931 return probe;
932 }
933
934
935 // Lookup or create a jmethodID.
936 // This code can be called by the VM thread. For this reason it is critical that
937 // there are no blocking operations (safepoints) while the lock is held -- or a
938 // deadlock can occur.
939 jmethodID instanceKlass::jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h) {
940 size_t idnum = (size_t)method_h->method_idnum();
941 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
942 size_t length = 0;
943 jmethodID id = NULL;
944 // array length stored in first element, other elements offset by one
945 if (jmeths == NULL || // If there is no jmethodID array,
946 (length = (size_t)jmeths[0]) <= idnum || // or if it is too short,
947 (id = jmeths[idnum+1]) == NULL) { // or if this jmethodID isn't allocated
948
949 // Do all the safepointing things (allocations) before grabbing the lock.
950 // These allocations will have to be freed if they are unused.
951
952 // Allocate a new array of methods.
953 jmethodID* to_dealloc_jmeths = NULL;
954 jmethodID* new_jmeths = NULL;
955 if (length <= idnum) {
956 // A new array will be needed (unless some other thread beats us to it)
957 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
958 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
959 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
960 new_jmeths[0] =(jmethodID)size; // array size held in the first element
961 }
962
963 // Allocate a new method ID.
964 jmethodID to_dealloc_id = NULL;
965 jmethodID new_id = NULL;
966 if (method_h->is_old() && !method_h->is_obsolete()) {
967 // The method passed in is old (but not obsolete), we need to use the current version
968 methodOop current_method = ik_h->method_with_idnum((int)idnum);
969 assert(current_method != NULL, "old and but not obsolete, so should exist");
970 methodHandle current_method_h(current_method == NULL? method_h() : current_method);
971 new_id = JNIHandles::make_jmethod_id(current_method_h);
972 } else {
973 // It is the current version of the method or an obsolete method,
974 // use the version passed in
975 new_id = JNIHandles::make_jmethod_id(method_h);
976 }
977
978 {
979 MutexLocker ml(JmethodIdCreation_lock);
980
981 // We must not go to a safepoint while holding this lock.
982 debug_only(No_Safepoint_Verifier nosafepoints;)
983
984 // Retry lookup after we got the lock
985 jmeths = ik_h->methods_jmethod_ids_acquire();
986 if (jmeths == NULL || (length = (size_t)jmeths[0]) <= idnum) {
987 if (jmeths != NULL) {
988 // We have grown the array: copy the existing entries, and delete the old array
989 for (size_t index = 0; index < length; index++) {
990 new_jmeths[index+1] = jmeths[index+1];
991 }
992 to_dealloc_jmeths = jmeths; // using the new jmeths, deallocate the old one
993 }
994 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
995 } else {
996 id = jmeths[idnum+1];
997 to_dealloc_jmeths = new_jmeths; // using the old jmeths, deallocate the new one
998 }
999 if (id == NULL) {
1000 id = new_id;
1001 jmeths[idnum+1] = id; // install the new method ID
1002 } else {
1003 to_dealloc_id = new_id; // the new id wasn't used, mark it for deallocation
1004 }
1005 }
1006
1007 // Free up unneeded or no longer needed resources
1008 FreeHeap(to_dealloc_jmeths);
1009 if (to_dealloc_id != NULL) {
1010 JNIHandles::destroy_jmethod_id(to_dealloc_id);
1011 }
1012 }
1013 return id;
1014 }
1015
1016
1017 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1018 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
1019 size_t idnum = (size_t)method->method_idnum();
1020 jmethodID* jmeths = methods_jmethod_ids_acquire();
1021 size_t length; // length assigned as debugging crumb
1022 jmethodID id = NULL;
1023 if (jmeths != NULL && // If there is a jmethodID array,
1024 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1025 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1026 }
1027 return id;
1028 }
1029
1030
1031 // Cache an itable index
1032 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
1033 int* indices = methods_cached_itable_indices_acquire();
1034 if (indices == NULL || // If there is no index array,
1035 ((size_t)indices[0]) <= idnum) { // or if it is too short
1036 // Lock before we allocate the array so we don't leak
1037 MutexLocker ml(JNICachedItableIndex_lock);
1038 // Retry lookup after we got the lock
1039 indices = methods_cached_itable_indices_acquire();
1040 size_t length = 0;
1041 // array length stored in first element, other elements offset by one
1042 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1043 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1044 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
1045 // Copy the existing entries, if any
1046 size_t i;
1047 for (i = 0; i < length; i++) {
1048 new_indices[i+1] = indices[i+1];
1049 }
1050 // Set all the rest to -1
1051 for (i = length; i < size; i++) {
1052 new_indices[i+1] = -1;
1053 }
1054 if (indices != NULL) {
1055 FreeHeap(indices); // delete any old indices
1056 }
1057 release_set_methods_cached_itable_indices(indices = new_indices);
1058 }
1059 } else {
1060 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1061 }
1062 // This is a cache, if there is a race to set it, it doesn't matter
1063 indices[idnum+1] = index;
1064 }
1065
1066
1067 // Retrieve a cached itable index
1068 int instanceKlass::cached_itable_index(size_t idnum) {
1069 int* indices = methods_cached_itable_indices_acquire();
1070 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1071 // indices exist and are long enough, retrieve possible cached
1072 return indices[idnum+1];
1073 }
1074 return -1;
1075 }
1076
1077
1078 //
1079 // nmethodBucket is used to record dependent nmethods for
1080 // deoptimization. nmethod dependencies are actually <klass, method>
1081 // pairs but we really only care about the klass part for purposes of
1082 // finding nmethods which might need to be deoptimized. Instead of
1083 // recording the method, a count of how many times a particular nmethod
1084 // was recorded is kept. This ensures that any recording errors are
1085 // noticed since an nmethod should be removed as many times are it's
1086 // added.
1087 //
1088 class nmethodBucket {
1089 private:
1090 nmethod* _nmethod;
1091 int _count;
1092 nmethodBucket* _next;
1093
1094 public:
1095 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1096 _nmethod = nmethod;
1097 _next = next;
1098 _count = 1;
1099 }
1100 int count() { return _count; }
1101 int increment() { _count += 1; return _count; }
1102 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1103 nmethodBucket* next() { return _next; }
1104 void set_next(nmethodBucket* b) { _next = b; }
1105 nmethod* get_nmethod() { return _nmethod; }
1106 };
1107
1108
1109 //
1110 // Walk the list of dependent nmethods searching for nmethods which
1111 // are dependent on the klassOop that was passed in and mark them for
1112 // deoptimization. Returns the number of nmethods found.
1113 //
1114 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
1115 assert_locked_or_safepoint(CodeCache_lock);
1116 int found = 0;
1117 nmethodBucket* b = _dependencies;
1118 while (b != NULL) {
1119 nmethod* nm = b->get_nmethod();
1120 // since dependencies aren't removed until an nmethod becomes a zombie,
1121 // the dependency list may contain nmethods which aren't alive.
1122 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1123 if (TraceDependencies) {
1124 ResourceMark rm;
1125 tty->print_cr("Marked for deoptimization");
1126 tty->print_cr(" context = %s", this->external_name());
1127 changes.print();
1128 nm->print();
1129 nm->print_dependencies();
1130 }
1131 nm->mark_for_deoptimization();
1132 found++;
1133 }
1134 b = b->next();
1135 }
1136 return found;
1137 }
1138
1139
1140 //
1141 // Add an nmethodBucket to the list of dependencies for this nmethod.
1142 // It's possible that an nmethod has multiple dependencies on this klass
1143 // so a count is kept for each bucket to guarantee that creation and
1144 // deletion of dependencies is consistent.
1145 //
1146 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
1147 assert_locked_or_safepoint(CodeCache_lock);
1148 nmethodBucket* b = _dependencies;
1149 nmethodBucket* last = NULL;
1150 while (b != NULL) {
1151 if (nm == b->get_nmethod()) {
1152 b->increment();
1153 return;
1154 }
1155 b = b->next();
1156 }
1157 _dependencies = new nmethodBucket(nm, _dependencies);
1158 }
1159
1160
1161 //
1162 // Decrement count of the nmethod in the dependency list and remove
1163 // the bucket competely when the count goes to 0. This method must
1164 // find a corresponding bucket otherwise there's a bug in the
1165 // recording of dependecies.
1166 //
1167 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
1168 assert_locked_or_safepoint(CodeCache_lock);
1169 nmethodBucket* b = _dependencies;
1170 nmethodBucket* last = NULL;
1171 while (b != NULL) {
1172 if (nm == b->get_nmethod()) {
1173 if (b->decrement() == 0) {
1174 if (last == NULL) {
1175 _dependencies = b->next();
1176 } else {
1177 last->set_next(b->next());
1178 }
1179 delete b;
1180 }
1181 return;
1182 }
1183 last = b;
1184 b = b->next();
1185 }
1186 #ifdef ASSERT
1187 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1188 nm->print();
1189 #endif // ASSERT
1190 ShouldNotReachHere();
1191 }
1192
1193
1194 #ifndef PRODUCT
1195 void instanceKlass::print_dependent_nmethods(bool verbose) {
1196 nmethodBucket* b = _dependencies;
1197 int idx = 0;
1198 while (b != NULL) {
1199 nmethod* nm = b->get_nmethod();
1200 tty->print("[%d] count=%d { ", idx++, b->count());
1201 if (!verbose) {
1202 nm->print_on(tty, "nmethod");
1203 tty->print_cr(" } ");
1204 } else {
1205 nm->print();
1206 nm->print_dependencies();
1207 tty->print_cr("--- } ");
1208 }
1209 b = b->next();
1210 }
1211 }
1212
1213
1214 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
1215 nmethodBucket* b = _dependencies;
1216 while (b != NULL) {
1217 if (nm == b->get_nmethod()) {
1218 return true;
1219 }
1220 b = b->next();
1221 }
1222 return false;
1223 }
1224 #endif //PRODUCT
1225
1226
1227 void instanceKlass::follow_static_fields() {
1228 oop* start = start_of_static_fields();
1229 oop* end = start + static_oop_field_size();
1230 while (start < end) {
1231 if (*start != NULL) {
1232 assert(Universe::heap()->is_in_closed_subset(*start),
1233 "should be in heap");
1234 MarkSweep::mark_and_push(start);
1235 }
1236 start++;
1237 }
1238 }
1239
1240 #ifndef SERIALGC
1241 void instanceKlass::follow_static_fields(ParCompactionManager* cm) {
1242 oop* start = start_of_static_fields();
1243 oop* end = start + static_oop_field_size();
1244 while (start < end) {
1245 if (*start != NULL) {
1246 assert(Universe::heap()->is_in(*start), "should be in heap");
1247 PSParallelCompact::mark_and_push(cm, start);
1248 }
1249 start++;
1250 }
1251 }
1252 #endif // SERIALGC
1253
1254
1255 void instanceKlass::adjust_static_fields() {
1256 oop* start = start_of_static_fields();
1257 oop* end = start + static_oop_field_size();
1258 while (start < end) {
1259 MarkSweep::adjust_pointer(start);
1260 start++;
1261 }
1262 }
1263
1264 #ifndef SERIALGC
1265 void instanceKlass::update_static_fields() {
1266 oop* const start = start_of_static_fields();
1267 oop* const beg_oop = start;
1268 oop* const end_oop = start + static_oop_field_size();
1269 for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) {
1270 PSParallelCompact::adjust_pointer(cur_oop);
1271 }
1272 }
1273
1274 void
1275 instanceKlass::update_static_fields(HeapWord* beg_addr, HeapWord* end_addr) {
1276 oop* const start = start_of_static_fields();
1277 oop* const beg_oop = MAX2((oop*)beg_addr, start);
1278 oop* const end_oop = MIN2((oop*)end_addr, start + static_oop_field_size());
1279 for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) {
1280 PSParallelCompact::adjust_pointer(cur_oop);
1281 }
1282 }
1283 #endif // SERIALGC
1284
1285 void instanceKlass::oop_follow_contents(oop obj) {
1286 assert (obj!=NULL, "can't follow the content of NULL object");
1287 obj->follow_header();
1288 OopMapBlock* map = start_of_nonstatic_oop_maps();
1289 OopMapBlock* end_map = map + nonstatic_oop_map_size();
1290 while (map < end_map) {
1291 oop* start = obj->obj_field_addr(map->offset());
1292 oop* end = start + map->length();
1293 while (start < end) {
1294 if (*start != NULL) {
1295 assert(Universe::heap()->is_in_closed_subset(*start),
1296 "should be in heap");
1297 MarkSweep::mark_and_push(start);
1298 }
1299 start++;
1300 }
1301 map++;
1302 }
1303 }
1304
1305 #ifndef SERIALGC
1306 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
1307 oop obj) {
1308 assert (obj!=NULL, "can't follow the content of NULL object");
1309 obj->follow_header(cm);
1310 OopMapBlock* map = start_of_nonstatic_oop_maps();
1311 OopMapBlock* end_map = map + nonstatic_oop_map_size();
1312 while (map < end_map) {
1313 oop* start = obj->obj_field_addr(map->offset());
1314 oop* end = start + map->length();
1315 while (start < end) {
1316 if (*start != NULL) {
1317 assert(Universe::heap()->is_in(*start), "should be in heap");
1318 PSParallelCompact::mark_and_push(cm, start);
1319 }
1320 start++;
1321 }
1322 map++;
1323 }
1324 }
1325 #endif // SERIALGC
1326
1327 #define invoke_closure_on(start, closure, nv_suffix) { \
1328 oop obj = *(start); \
1329 if (obj != NULL) { \
1330 assert(Universe::heap()->is_in_closed_subset(obj), "should be in heap"); \
1331 (closure)->do_oop##nv_suffix(start); \
1332 } \
1333 }
1334
1335 // closure's do_header() method dicates whether the given closure should be
1336 // applied to the klass ptr in the object header.
1337
1338 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
1339 \
1340 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, \
1341 OopClosureType* closure) { \
1342 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
1343 /* header */ \
1344 if (closure->do_header()) { \
1345 obj->oop_iterate_header(closure); \
1346 } \
1347 /* instance variables */ \
1348 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1349 OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \
1350 const intx field_offset = PrefetchFieldsAhead; \
1351 if (field_offset > 0) { \
1352 while (map < end_map) { \
1353 oop* start = obj->obj_field_addr(map->offset()); \
1354 oop* const end = start + map->length(); \
1355 while (start < end) { \
1356 prefetch_beyond(start, (oop*)end, field_offset, \
1357 closure->prefetch_style()); \
1358 SpecializationStats:: \
1359 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
1360 invoke_closure_on(start, closure, nv_suffix); \
1361 start++; \
1362 } \
1363 map++; \
1364 } \
1365 } else { \
1366 while (map < end_map) { \
1367 oop* start = obj->obj_field_addr(map->offset()); \
1368 oop* const end = start + map->length(); \
1369 while (start < end) { \
1370 SpecializationStats:: \
1371 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
1372 invoke_closure_on(start, closure, nv_suffix); \
1373 start++; \
1374 } \
1375 map++; \
1376 } \
1377 } \
1378 return size_helper(); \
1379 }
1380
1381 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
1382 \
1383 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
1384 OopClosureType* closure, \
1385 MemRegion mr) { \
1386 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
1387 /* header */ \
1388 if (closure->do_header()) { \
1389 obj->oop_iterate_header(closure, mr); \
1390 } \
1391 /* instance variables */ \
1392 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1393 OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \
1394 HeapWord* bot = mr.start(); \
1395 HeapWord* top = mr.end(); \
1396 oop* start = obj->obj_field_addr(map->offset()); \
1397 HeapWord* end = MIN2((HeapWord*)(start + map->length()), top); \
1398 /* Find the first map entry that extends onto mr. */ \
1399 while (map < end_map && end <= bot) { \
1400 map++; \
1401 start = obj->obj_field_addr(map->offset()); \
1402 end = MIN2((HeapWord*)(start + map->length()), top); \
1403 } \
1404 if (map != end_map) { \
1405 /* The current map's end is past the start of "mr". Skip up to the first \
1406 entry on "mr". */ \
1407 while ((HeapWord*)start < bot) { \
1408 start++; \
1409 } \
1410 const intx field_offset = PrefetchFieldsAhead; \
1411 for (;;) { \
1412 if (field_offset > 0) { \
1413 while ((HeapWord*)start < end) { \
1414 prefetch_beyond(start, (oop*)end, field_offset, \
1415 closure->prefetch_style()); \
1416 invoke_closure_on(start, closure, nv_suffix); \
1417 start++; \
1418 } \
1419 } else { \
1420 while ((HeapWord*)start < end) { \
1421 invoke_closure_on(start, closure, nv_suffix); \
1422 start++; \
1423 } \
1424 } \
1425 /* Go to the next map. */ \
1426 map++; \
1427 if (map == end_map) { \
1428 break; \
1429 } \
1430 /* Otherwise, */ \
1431 start = obj->obj_field_addr(map->offset()); \
1432 if ((HeapWord*)start >= top) { \
1433 break; \
1434 } \
1435 end = MIN2((HeapWord*)(start + map->length()), top); \
1436 } \
1437 } \
1438 return size_helper(); \
1439 }
1440
1441 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1442 ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1443 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1444 ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1445
1446
1447 void instanceKlass::iterate_static_fields(OopClosure* closure) {
1448 oop* start = start_of_static_fields();
1449 oop* end = start + static_oop_field_size();
1450 while (start < end) {
1451 assert(Universe::heap()->is_in_reserved_or_null(*start), "should be in heap");
1452 closure->do_oop(start);
1453 start++;
1454 }
1455 }
1456
1457 void instanceKlass::iterate_static_fields(OopClosure* closure,
1458 MemRegion mr) {
1459 oop* start = start_of_static_fields();
1460 oop* end = start + static_oop_field_size();
1461 // I gather that the the static fields of reference types come first,
1462 // hence the name of "oop_field_size", and that is what makes this safe.
1463 assert((intptr_t)mr.start() ==
1464 align_size_up((intptr_t)mr.start(), sizeof(oop)) &&
1465 (intptr_t)mr.end() == align_size_up((intptr_t)mr.end(), sizeof(oop)),
1466 "Memregion must be oop-aligned.");
1467 if ((HeapWord*)start < mr.start()) start = (oop*)mr.start();
1468 if ((HeapWord*)end > mr.end()) end = (oop*)mr.end();
1469 while (start < end) {
1470 invoke_closure_on(start, closure,_v);
1471 start++;
1472 }
1473 }
1474
1475
1476 int instanceKlass::oop_adjust_pointers(oop obj) {
1477 int size = size_helper();
1478
1479 // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1.
1480 OopMapBlock* map = start_of_nonstatic_oop_maps();
1481 OopMapBlock* const end_map = map + nonstatic_oop_map_size();
1482 // Iterate over oopmap blocks
1483 while (map < end_map) {
1484 // Compute oop range for this block
1485 oop* start = obj->obj_field_addr(map->offset());
1486 oop* end = start + map->length();
1487 // Iterate over oops
1488 while (start < end) {
1489 assert(Universe::heap()->is_in_or_null(*start), "should be in heap");
1490 MarkSweep::adjust_pointer(start);
1491 start++;
1492 }
1493 map++;
1494 }
1495
1496 obj->adjust_header();
1497 return size;
1498 }
1499
1500 #ifndef SERIALGC
1501 void instanceKlass::oop_copy_contents(PSPromotionManager* pm, oop obj) {
1502 assert(!pm->depth_first(), "invariant");
1503 // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1.
1504 OopMapBlock* start_map = start_of_nonstatic_oop_maps();
1505 OopMapBlock* map = start_map + nonstatic_oop_map_size();
1506
1507 // Iterate over oopmap blocks
1508 while (start_map < map) {
1509 --map;
1510 // Compute oop range for this block
1511 oop* start = obj->obj_field_addr(map->offset());
1512 oop* curr = start + map->length();
1513 // Iterate over oops
1514 while (start < curr) {
1515 --curr;
1516 if (PSScavenge::should_scavenge(*curr)) {
1517 assert(Universe::heap()->is_in(*curr), "should be in heap");
1518 pm->claim_or_forward_breadth(curr);
1519 }
1520 }
1521 }
1522 }
1523
1524 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
1525 assert(pm->depth_first(), "invariant");
1526 // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1.
1527 OopMapBlock* start_map = start_of_nonstatic_oop_maps();
1528 OopMapBlock* map = start_map + nonstatic_oop_map_size();
1529
1530 // Iterate over oopmap blocks
1531 while (start_map < map) {
1532 --map;
1533 // Compute oop range for this block
1534 oop* start = obj->obj_field_addr(map->offset());
1535 oop* curr = start + map->length();
1536 // Iterate over oops
1537 while (start < curr) {
1538 --curr;
1539 if (PSScavenge::should_scavenge(*curr)) {
1540 assert(Universe::heap()->is_in(*curr), "should be in heap");
1541 pm->claim_or_forward_depth(curr);
1542 }
1543 }
1544 }
1545 }
1546
1547 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
1548 // Compute oopmap block range. The common case is nonstatic_oop_map_size==1.
1549 OopMapBlock* map = start_of_nonstatic_oop_maps();
1550 OopMapBlock* const end_map = map + nonstatic_oop_map_size();
1551 // Iterate over oopmap blocks
1552 while (map < end_map) {
1553 // Compute oop range for this oopmap block.
1554 oop* const map_start = obj->obj_field_addr(map->offset());
1555 oop* const beg_oop = map_start;
1556 oop* const end_oop = map_start + map->length();
1557 for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) {
1558 PSParallelCompact::adjust_pointer(cur_oop);
1559 }
1560 ++map;
1561 }
1562
1563 return size_helper();
1564 }
1565
1566 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj,
1567 HeapWord* beg_addr, HeapWord* end_addr) {
1568 // Compute oopmap block range. The common case is nonstatic_oop_map_size==1.
1569 OopMapBlock* map = start_of_nonstatic_oop_maps();
1570 OopMapBlock* const end_map = map + nonstatic_oop_map_size();
1571 // Iterate over oopmap blocks
1572 while (map < end_map) {
1573 // Compute oop range for this oopmap block.
1574 oop* const map_start = obj->obj_field_addr(map->offset());
1575 oop* const beg_oop = MAX2((oop*)beg_addr, map_start);
1576 oop* const end_oop = MIN2((oop*)end_addr, map_start + map->length());
1577 for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) {
1578 PSParallelCompact::adjust_pointer(cur_oop);
1579 }
1580 ++map;
1581 }
1582
1583 return size_helper();
1584 }
1585
1586 void instanceKlass::copy_static_fields(PSPromotionManager* pm) {
1587 assert(!pm->depth_first(), "invariant");
1588 // Compute oop range
1589 oop* start = start_of_static_fields();
1590 oop* end = start + static_oop_field_size();
1591 // Iterate over oops
1592 while (start < end) {
1593 if (PSScavenge::should_scavenge(*start)) {
1594 assert(Universe::heap()->is_in(*start), "should be in heap");
1595 pm->claim_or_forward_breadth(start);
1596 }
1597 start++;
1598 }
1599 }
1600
1601 void instanceKlass::push_static_fields(PSPromotionManager* pm) {
1602 assert(pm->depth_first(), "invariant");
1603 // Compute oop range
1604 oop* start = start_of_static_fields();
1605 oop* end = start + static_oop_field_size();
1606 // Iterate over oops
1607 while (start < end) {
1608 if (PSScavenge::should_scavenge(*start)) {
1609 assert(Universe::heap()->is_in(*start), "should be in heap");
1610 pm->claim_or_forward_depth(start);
1611 }
1612 start++;
1613 }
1614 }
1615
1616 void instanceKlass::copy_static_fields(ParCompactionManager* cm) {
1617 // Compute oop range
1618 oop* start = start_of_static_fields();
1619 oop* end = start + static_oop_field_size();
1620 // Iterate over oops
1621 while (start < end) {
1622 if (*start != NULL) {
1623 assert(Universe::heap()->is_in(*start), "should be in heap");
1624 // *start = (oop) cm->summary_data()->calc_new_pointer(*start);
1625 PSParallelCompact::adjust_pointer(start);
1626 }
1627 start++;
1628 }
1629 }
1630 #endif // SERIALGC
1631
1632 // This klass is alive but the implementor link is not followed/updated.
1633 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
1634
1635 void instanceKlass::follow_weak_klass_links(
1636 BoolObjectClosure* is_alive, OopClosure* keep_alive) {
1637 assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
1638 if (ClassUnloading) {
1639 for (int i = 0; i < implementors_limit; i++) {
1640 klassOop impl = _implementors[i];
1641 if (impl == NULL) break; // no more in the list
1642 if (!is_alive->do_object_b(impl)) {
1643 // remove this guy from the list by overwriting him with the tail
1644 int lasti = --_nof_implementors;
1645 assert(lasti >= i && lasti < implementors_limit, "just checking");
1646 _implementors[i] = _implementors[lasti];
1647 _implementors[lasti] = NULL;
1648 --i; // rerun the loop at this index
1649 }
1650 }
1651 } else {
1652 for (int i = 0; i < implementors_limit; i++) {
1653 keep_alive->do_oop(&adr_implementors()[i]);
1654 }
1655 }
1656 Klass::follow_weak_klass_links(is_alive, keep_alive);
1657 }
1658
1659
1660 void instanceKlass::remove_unshareable_info() {
1661 Klass::remove_unshareable_info();
1662 init_implementor();
1663 }
1664
1665
1666 static void clear_all_breakpoints(methodOop m) {
1667 m->clear_all_breakpoints();
1668 }
1669
1670
1671 void instanceKlass::release_C_heap_structures() {
1672 // Deallocate oop map cache
1673 if (_oop_map_cache != NULL) {
1674 delete _oop_map_cache;
1675 _oop_map_cache = NULL;
1676 }
1677
1678 // Deallocate JNI identifiers for jfieldIDs
1679 JNIid::deallocate(jni_ids());
1680 set_jni_ids(NULL);
1681
1682 jmethodID* jmeths = methods_jmethod_ids_acquire();
1683 if (jmeths != (jmethodID*)NULL) {
1684 release_set_methods_jmethod_ids(NULL);
1685 FreeHeap(jmeths);
1686 }
1687
1688 int* indices = methods_cached_itable_indices_acquire();
1689 if (indices != (int*)NULL) {
1690 release_set_methods_cached_itable_indices(NULL);
1691 FreeHeap(indices);
1692 }
1693
1694 // release dependencies
1695 nmethodBucket* b = _dependencies;
1696 _dependencies = NULL;
1697 while (b != NULL) {
1698 nmethodBucket* next = b->next();
1699 delete b;
1700 b = next;
1701 }
1702
1703 // Deallocate breakpoint records
1704 if (breakpoints() != 0x0) {
1705 methods_do(clear_all_breakpoints);
1706 assert(breakpoints() == 0x0, "should have cleared breakpoints");
1707 }
1708
1709 // deallocate information about previous versions
1710 if (_previous_versions != NULL) {
1711 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
1712 PreviousVersionNode * pv_node = _previous_versions->at(i);
1713 delete pv_node;
1714 }
1715 delete _previous_versions;
1716 _previous_versions = NULL;
1717 }
1718
1719 // deallocate the cached class file
1720 if (_cached_class_file_bytes != NULL) {
1721 os::free(_cached_class_file_bytes);
1722 _cached_class_file_bytes = NULL;
1723 _cached_class_file_len = 0;
1724 }
1725 }
1726
1727 char* instanceKlass::signature_name() const {
1728 const char* src = (const char*) (name()->as_C_string());
1729 const int src_length = (int)strlen(src);
1730 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
1731 int src_index = 0;
1732 int dest_index = 0;
1733 dest[dest_index++] = 'L';
1734 while (src_index < src_length) {
1735 dest[dest_index++] = src[src_index++];
1736 }
1737 dest[dest_index++] = ';';
1738 dest[dest_index] = '\0';
1739 return dest;
1740 }
1741
1742 // different verisons of is_same_class_package
1743 bool instanceKlass::is_same_class_package(klassOop class2) {
1744 klassOop class1 = as_klassOop();
1745 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1746 symbolOop classname1 = Klass::cast(class1)->name();
1747
1748 if (Klass::cast(class2)->oop_is_objArray()) {
1749 class2 = objArrayKlass::cast(class2)->bottom_klass();
1750 }
1751 oop classloader2;
1752 if (Klass::cast(class2)->oop_is_instance()) {
1753 classloader2 = instanceKlass::cast(class2)->class_loader();
1754 } else {
1755 assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
1756 classloader2 = NULL;
1757 }
1758 symbolOop classname2 = Klass::cast(class2)->name();
1759
1760 return instanceKlass::is_same_class_package(classloader1, classname1,
1761 classloader2, classname2);
1762 }
1763
1764 bool instanceKlass::is_same_class_package(oop classloader2, symbolOop classname2) {
1765 klassOop class1 = as_klassOop();
1766 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1767 symbolOop classname1 = Klass::cast(class1)->name();
1768
1769 return instanceKlass::is_same_class_package(classloader1, classname1,
1770 classloader2, classname2);
1771 }
1772
1773 // return true if two classes are in the same package, classloader
1774 // and classname information is enough to determine a class's package
1775 bool instanceKlass::is_same_class_package(oop class_loader1, symbolOop class_name1,
1776 oop class_loader2, symbolOop class_name2) {
1777 if (class_loader1 != class_loader2) {
1778 return false;
1779 } else {
1780 ResourceMark rm;
1781
1782 // The symbolOop's are in UTF8 encoding. Since we only need to check explicitly
1783 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
1784 // Otherwise, we just compare jbyte values between the strings.
1785 jbyte *name1 = class_name1->base();
1786 jbyte *name2 = class_name2->base();
1787
1788 jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
1789 jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
1790
1791 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
1792 // One of the two doesn't have a package. Only return true
1793 // if the other one also doesn't have a package.
1794 return last_slash1 == last_slash2;
1795 } else {
1796 // Skip over '['s
1797 if (*name1 == '[') {
1798 do {
1799 name1++;
1800 } while (*name1 == '[');
1801 if (*name1 != 'L') {
1802 // Something is terribly wrong. Shouldn't be here.
1803 return false;
1804 }
1805 }
1806 if (*name2 == '[') {
1807 do {
1808 name2++;
1809 } while (*name2 == '[');
1810 if (*name2 != 'L') {
1811 // Something is terribly wrong. Shouldn't be here.
1812 return false;
1813 }
1814 }
1815
1816 // Check that package part is identical
1817 int length1 = last_slash1 - name1;
1818 int length2 = last_slash2 - name2;
1819
1820 return UTF8::equal(name1, length1, name2, length2);
1821 }
1822 }
1823 }
1824
1825
1826 jint instanceKlass::compute_modifier_flags(TRAPS) const {
1827 klassOop k = as_klassOop();
1828 jint access = access_flags().as_int();
1829
1830 // But check if it happens to be member class.
1831 typeArrayOop inner_class_list = inner_classes();
1832 int length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
1833 assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
1834 if (length > 0) {
1835 typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
1836 instanceKlassHandle ik(THREAD, k);
1837 for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
1838 int ioff = inner_class_list_h->ushort_at(
1839 i + instanceKlass::inner_class_inner_class_info_offset);
1840
1841 // Inner class attribute can be zero, skip it.
1842 // Strange but true: JVM spec. allows null inner class refs.
1843 if (ioff == 0) continue;
1844
1845 // only look at classes that are already loaded
1846 // since we are looking for the flags for our self.
1847 symbolOop inner_name = ik->constants()->klass_name_at(ioff);
1848 if ((ik->name() == inner_name)) {
1849 // This is really a member class.
1850 access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset);
1851 break;
1852 }
1853 }
1854 }
1855 // Remember to strip ACC_SUPER bit
1856 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
1857 }
1858
1859 jint instanceKlass::jvmti_class_status() const {
1860 jint result = 0;
1861
1862 if (is_linked()) {
1863 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
1864 }
1865
1866 if (is_initialized()) {
1867 assert(is_linked(), "Class status is not consistent");
1868 result |= JVMTI_CLASS_STATUS_INITIALIZED;
1869 }
1870 if (is_in_error_state()) {
1871 result |= JVMTI_CLASS_STATUS_ERROR;
1872 }
1873 return result;
1874 }
1875
1876 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
1877 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
1878 int method_table_offset_in_words = ioe->offset()/wordSize;
1879 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
1880 / itableOffsetEntry::size();
1881
1882 for (int cnt = 0 ; ; cnt ++, ioe ++) {
1883 // If the interface isn't implemented by the reciever class,
1884 // the VM should throw IncompatibleClassChangeError.
1885 if (cnt >= nof_interfaces) {
1886 THROW_OOP_0(vmSymbols::java_lang_IncompatibleClassChangeError());
1887 }
1888
1889 klassOop ik = ioe->interface_klass();
1890 if (ik == holder) break;
1891 }
1892
1893 itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
1894 methodOop m = ime[index].method();
1895 if (m == NULL) {
1896 THROW_OOP_0(vmSymbols::java_lang_AbstractMethodError());
1897 }
1898 return m;
1899 }
1900
1901 // On-stack replacement stuff
1902 void instanceKlass::add_osr_nmethod(nmethod* n) {
1903 // only one compilation can be active
1904 NEEDS_CLEANUP
1905 // This is a short non-blocking critical region, so the no safepoint check is ok.
1906 OsrList_lock->lock_without_safepoint_check();
1907 assert(n->is_osr_method(), "wrong kind of nmethod");
1908 n->set_link(osr_nmethods_head());
1909 set_osr_nmethods_head(n);
1910 // Remember to unlock again
1911 OsrList_lock->unlock();
1912 }
1913
1914
1915 void instanceKlass::remove_osr_nmethod(nmethod* n) {
1916 // This is a short non-blocking critical region, so the no safepoint check is ok.
1917 OsrList_lock->lock_without_safepoint_check();
1918 assert(n->is_osr_method(), "wrong kind of nmethod");
1919 nmethod* last = NULL;
1920 nmethod* cur = osr_nmethods_head();
1921 // Search for match
1922 while(cur != NULL && cur != n) {
1923 last = cur;
1924 cur = cur->link();
1925 }
1926 if (cur == n) {
1927 if (last == NULL) {
1928 // Remove first element
1929 set_osr_nmethods_head(osr_nmethods_head()->link());
1930 } else {
1931 last->set_link(cur->link());
1932 }
1933 }
1934 n->set_link(NULL);
1935 // Remember to unlock again
1936 OsrList_lock->unlock();
1937 }
1938
1939 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci) const {
1940 // This is a short non-blocking critical region, so the no safepoint check is ok.
1941 OsrList_lock->lock_without_safepoint_check();
1942 nmethod* osr = osr_nmethods_head();
1943 while (osr != NULL) {
1944 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
1945 if (osr->method() == m &&
1946 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
1947 // Found a match - return it.
1948 OsrList_lock->unlock();
1949 return osr;
1950 }
1951 osr = osr->link();
1952 }
1953 OsrList_lock->unlock();
1954 return NULL;
1955 }
1956
1957 // -----------------------------------------------------------------------------------------------------
1958 #ifndef PRODUCT
1959
1960 // Printing
1961
1962 void FieldPrinter::do_field(fieldDescriptor* fd) {
1963 if (fd->is_static() == (_obj == NULL)) {
1964 _st->print(" - ");
1965 fd->print_on(_st);
1966 _st->cr();
1967 } else {
1968 fd->print_on_for(_st, _obj);
1969 _st->cr();
1970 }
1971 }
1972
1973
1974 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
1975 Klass::oop_print_on(obj, st);
1976
1977 if (as_klassOop() == SystemDictionary::string_klass()) {
1978 typeArrayOop value = java_lang_String::value(obj);
1979 juint offset = java_lang_String::offset(obj);
1980 juint length = java_lang_String::length(obj);
1981 if (value != NULL &&
1982 value->is_typeArray() &&
1983 offset <= (juint) value->length() &&
1984 offset + length <= (juint) value->length()) {
1985 st->print("string: ");
1986 Handle h_obj(obj);
1987 java_lang_String::print(h_obj, st);
1988 st->cr();
1989 if (!WizardMode) return; // that is enough
1990 }
1991 }
1992
1993 st->print_cr("fields:");
1994 FieldPrinter print_nonstatic_field(st, obj);
1995 do_nonstatic_fields(&print_nonstatic_field);
1996
1997 if (as_klassOop() == SystemDictionary::class_klass()) {
1998 klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
1999 st->print(" - fake entry for mirror: ");
2000 mirrored_klass->print_value_on(st);
2001 st->cr();
2002 st->print(" - fake entry resolved_constructor: ");
2003 methodOop ctor = java_lang_Class::resolved_constructor(obj);
2004 ctor->print_value_on(st);
2005 klassOop array_klass = java_lang_Class::array_klass(obj);
2006 st->print(" - fake entry for array: ");
2007 array_klass->print_value_on(st);
2008 st->cr();
2009 st->cr();
2010 }
2011 }
2012
2013 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2014 st->print("a ");
2015 name()->print_value_on(st);
2016 obj->print_address_on(st);
2017 }
2018
2019 #endif
2020
2021 const char* instanceKlass::internal_name() const {
2022 return external_name();
2023 }
2024
2025
2026
2027 // Verification
2028
2029 class VerifyFieldClosure: public OopClosure {
2030 public:
2031 void do_oop(oop* p) {
2032 guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
2033 if (!(*p)->is_oop_or_null()) {
2034 tty->print_cr("Failed: %p -> %p",p,(address)*p);
2035 Universe::print();
2036 guarantee(false, "boom");
2037 }
2038 }
2039 };
2040
2041
2042 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
2043 Klass::oop_verify_on(obj, st);
2044 VerifyFieldClosure blk;
2045 oop_oop_iterate(obj, &blk);
2046 }
2047
2048 #ifndef PRODUCT
2049
2050 void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) {
2051 // This verification code is disabled. JDK_Version::is_gte_jdk14x_version()
2052 // cannot be called since this function is called before the VM is
2053 // able to determine what JDK version is running with.
2054 // The check below always is false since 1.4.
2055 return;
2056
2057 // This verification code temporarily disabled for the 1.4
2058 // reflection implementation since java.lang.Class now has
2059 // Java-level instance fields. Should rewrite this to handle this
2060 // case.
2061 if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) {
2062 // Verify that java.lang.Class instances have a fake oop field added.
2063 instanceKlass* ik = instanceKlass::cast(k);
2064
2065 // Check that we have the right class
2066 static bool first_time = true;
2067 guarantee(k == SystemDictionary::class_klass() && first_time, "Invalid verify of maps");
2068 first_time = false;
2069 const int extra = java_lang_Class::number_of_fake_oop_fields;
2070 guarantee(ik->nonstatic_field_size() == extra, "just checking");
2071 guarantee(ik->nonstatic_oop_map_size() == 1, "just checking");
2072 guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking");
2073
2074 // Check that the map is (2,extra)
2075 int offset = java_lang_Class::klass_offset;
2076
2077 OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
2078 guarantee(map->offset() == offset && map->length() == extra, "just checking");
2079 }
2080 }
2081
2082 #endif
2083
2084
2085 /* JNIid class for jfieldIDs only */
2086 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
2087 _holder = holder;
2088 _offset = offset;
2089 _next = next;
2090 debug_only(_is_static_field_id = false;)
2091 }
2092
2093
2094 JNIid* JNIid::find(int offset) {
2095 JNIid* current = this;
2096 while (current != NULL) {
2097 if (current->offset() == offset) return current;
2098 current = current->next();
2099 }
2100 return NULL;
2101 }
2102
2103 void JNIid::oops_do(OopClosure* f) {
2104 for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
2105 f->do_oop(cur->holder_addr());
2106 }
2107 }
2108
2109 void JNIid::deallocate(JNIid* current) {
2110 while (current != NULL) {
2111 JNIid* next = current->next();
2112 delete current;
2113 current = next;
2114 }
2115 }
2116
2117
2118 void JNIid::verify(klassOop holder) {
2119 int first_field_offset = instanceKlass::cast(holder)->offset_of_static_fields();
2120 int end_field_offset;
2121 end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
2122
2123 JNIid* current = this;
2124 while (current != NULL) {
2125 guarantee(current->holder() == holder, "Invalid klass in JNIid");
2126 #ifdef ASSERT
2127 int o = current->offset();
2128 if (current->is_static_field_id()) {
2129 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
2130 }
2131 #endif
2132 current = current->next();
2133 }
2134 }
2135
2136
2137 #ifdef ASSERT
2138 void instanceKlass::set_init_state(ClassState state) {
2139 bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
2140 : (_init_state < state);
2141 assert(good_state || state == allocated, "illegal state transition");
2142 _init_state = state;
2143 }
2144 #endif
2145
2146
2147 // RedefineClasses() support for previous versions:
2148
2149 // Add an information node that contains weak references to the
2150 // interesting parts of the previous version of the_class.
2151 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
2152 BitMap * emcp_methods, int emcp_method_count) {
2153 assert(Thread::current()->is_VM_thread(),
2154 "only VMThread can add previous versions");
2155
2156 if (_previous_versions == NULL) {
2157 // This is the first previous version so make some space.
2158 // Start with 2 elements under the assumption that the class
2159 // won't be redefined much.
2160 _previous_versions = new (ResourceObj::C_HEAP)
2161 GrowableArray<PreviousVersionNode *>(2, true);
2162 }
2163
2164 // RC_TRACE macro has an embedded ResourceMark
2165 RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
2166 ikh->external_name(), _previous_versions->length(), emcp_method_count));
2167 constantPoolHandle cp_h(ikh->constants());
2168 jweak cp_ref = JNIHandles::make_weak_global(cp_h);
2169 PreviousVersionNode * pv_node = NULL;
2170 objArrayOop old_methods = ikh->methods();
2171
2172 if (emcp_method_count == 0) {
2173 pv_node = new PreviousVersionNode(cp_ref, NULL);
2174 RC_TRACE(0x00000400,
2175 ("add: all methods are obsolete; flushing any EMCP weak refs"));
2176 } else {
2177 int local_count = 0;
2178 GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
2179 GrowableArray<jweak>(emcp_method_count, true);
2180 for (int i = 0; i < old_methods->length(); i++) {
2181 if (emcp_methods->at(i)) {
2182 // this old method is EMCP so save a weak ref
2183 methodOop old_method = (methodOop) old_methods->obj_at(i);
2184 methodHandle old_method_h(old_method);
2185 jweak method_ref = JNIHandles::make_weak_global(old_method_h);
2186 method_refs->append(method_ref);
2187 if (++local_count >= emcp_method_count) {
2188 // no more EMCP methods so bail out now
2189 break;
2190 }
2191 }
2192 }
2193 pv_node = new PreviousVersionNode(cp_ref, method_refs);
2194 }
2195
2196 _previous_versions->append(pv_node);
2197
2198 // Using weak references allows the interesting parts of previous
2199 // classes to be GC'ed when they are no longer needed. Since the
2200 // caller is the VMThread and we are at a safepoint, this is a good
2201 // time to clear out unused weak references.
2202
2203 RC_TRACE(0x00000400, ("add: previous version length=%d",
2204 _previous_versions->length()));
2205
2206 // skip the last entry since we just added it
2207 for (int i = _previous_versions->length() - 2; i >= 0; i--) {
2208 // check the previous versions array for a GC'ed weak refs
2209 pv_node = _previous_versions->at(i);
2210 cp_ref = pv_node->prev_constant_pool();
2211 assert(cp_ref != NULL, "weak cp ref was unexpectedly cleared");
2212 if (cp_ref == NULL) {
2213 delete pv_node;
2214 _previous_versions->remove_at(i);
2215 // Since we are traversing the array backwards, we don't have to
2216 // do anything special with the index.
2217 continue; // robustness
2218 }
2219
2220 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2221 if (cp == NULL) {
2222 // this entry has been GC'ed so remove it
2223 delete pv_node;
2224 _previous_versions->remove_at(i);
2225 // Since we are traversing the array backwards, we don't have to
2226 // do anything special with the index.
2227 continue;
2228 } else {
2229 RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
2230 }
2231
2232 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2233 if (method_refs != NULL) {
2234 RC_TRACE(0x00000400, ("add: previous methods length=%d",
2235 method_refs->length()));
2236 for (int j = method_refs->length() - 1; j >= 0; j--) {
2237 jweak method_ref = method_refs->at(j);
2238 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2239 if (method_ref == NULL) {
2240 method_refs->remove_at(j);
2241 // Since we are traversing the array backwards, we don't have to
2242 // do anything special with the index.
2243 continue; // robustness
2244 }
2245
2246 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2247 if (method == NULL || emcp_method_count == 0) {
2248 // This method entry has been GC'ed or the current
2249 // RedefineClasses() call has made all methods obsolete
2250 // so remove it.
2251 JNIHandles::destroy_weak_global(method_ref);
2252 method_refs->remove_at(j);
2253 } else {
2254 // RC_TRACE macro has an embedded ResourceMark
2255 RC_TRACE(0x00000400,
2256 ("add: %s(%s): previous method @%d in version @%d is alive",
2257 method->name()->as_C_string(), method->signature()->as_C_string(),
2258 j, i));
2259 }
2260 }
2261 }
2262 }
2263
2264 int obsolete_method_count = old_methods->length() - emcp_method_count;
2265
2266 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
2267 _previous_versions->length() > 1) {
2268 // We have a mix of obsolete and EMCP methods. If there is more
2269 // than the previous version that we just added, then we have to
2270 // clear out any matching EMCP method entries the hard way.
2271 int local_count = 0;
2272 for (int i = 0; i < old_methods->length(); i++) {
2273 if (!emcp_methods->at(i)) {
2274 // only obsolete methods are interesting
2275 methodOop old_method = (methodOop) old_methods->obj_at(i);
2276 symbolOop m_name = old_method->name();
2277 symbolOop m_signature = old_method->signature();
2278
2279 // skip the last entry since we just added it
2280 for (int j = _previous_versions->length() - 2; j >= 0; j--) {
2281 // check the previous versions array for a GC'ed weak refs
2282 pv_node = _previous_versions->at(j);
2283 cp_ref = pv_node->prev_constant_pool();
2284 assert(cp_ref != NULL, "weak cp ref was unexpectedly cleared");
2285 if (cp_ref == NULL) {
2286 delete pv_node;
2287 _previous_versions->remove_at(j);
2288 // Since we are traversing the array backwards, we don't have to
2289 // do anything special with the index.
2290 continue; // robustness
2291 }
2292
2293 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2294 if (cp == NULL) {
2295 // this entry has been GC'ed so remove it
2296 delete pv_node;
2297 _previous_versions->remove_at(j);
2298 // Since we are traversing the array backwards, we don't have to
2299 // do anything special with the index.
2300 continue;
2301 }
2302
2303 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2304 if (method_refs == NULL) {
2305 // We have run into a PreviousVersion generation where
2306 // all methods were made obsolete during that generation's
2307 // RedefineClasses() operation. At the time of that
2308 // operation, all EMCP methods were flushed so we don't
2309 // have to go back any further.
2310 //
2311 // A NULL method_refs is different than an empty method_refs.
2312 // We cannot infer any optimizations about older generations
2313 // from an empty method_refs for the current generation.
2314 break;
2315 }
2316
2317 for (int k = method_refs->length() - 1; k >= 0; k--) {
2318 jweak method_ref = method_refs->at(k);
2319 assert(method_ref != NULL,
2320 "weak method ref was unexpectedly cleared");
2321 if (method_ref == NULL) {
2322 method_refs->remove_at(k);
2323 // Since we are traversing the array backwards, we don't
2324 // have to do anything special with the index.
2325 continue; // robustness
2326 }
2327
2328 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2329 if (method == NULL) {
2330 // this method entry has been GC'ed so skip it
2331 JNIHandles::destroy_weak_global(method_ref);
2332 method_refs->remove_at(k);
2333 continue;
2334 }
2335
2336 if (method->name() == m_name &&
2337 method->signature() == m_signature) {
2338 // The current RedefineClasses() call has made all EMCP
2339 // versions of this method obsolete so mark it as obsolete
2340 // and remove the weak ref.
2341 RC_TRACE(0x00000400,
2342 ("add: %s(%s): flush obsolete method @%d in version @%d",
2343 m_name->as_C_string(), m_signature->as_C_string(), k, j));
2344
2345 method->set_is_obsolete();
2346 JNIHandles::destroy_weak_global(method_ref);
2347 method_refs->remove_at(k);
2348 break;
2349 }
2350 }
2351
2352 // The previous loop may not find a matching EMCP method, but
2353 // that doesn't mean that we can optimize and not go any
2354 // further back in the PreviousVersion generations. The EMCP
2355 // method for this generation could have already been GC'ed,
2356 // but there still may be an older EMCP method that has not
2357 // been GC'ed.
2358 }
2359
2360 if (++local_count >= obsolete_method_count) {
2361 // no more obsolete methods so bail out now
2362 break;
2363 }
2364 }
2365 }
2366 }
2367 } // end add_previous_version()
2368
2369
2370 // Determine if instanceKlass has a previous version.
2371 bool instanceKlass::has_previous_version() const {
2372 if (_previous_versions == NULL) {
2373 // no previous versions array so answer is easy
2374 return false;
2375 }
2376
2377 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2378 // Check the previous versions array for an info node that hasn't
2379 // been GC'ed
2380 PreviousVersionNode * pv_node = _previous_versions->at(i);
2381
2382 jweak cp_ref = pv_node->prev_constant_pool();
2383 assert(cp_ref != NULL, "weak reference was unexpectedly cleared");
2384 if (cp_ref == NULL) {
2385 continue; // robustness
2386 }
2387
2388 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2389 if (cp != NULL) {
2390 // we have at least one previous version
2391 return true;
2392 }
2393
2394 // We don't have to check the method refs. If the constant pool has
2395 // been GC'ed then so have the methods.
2396 }
2397
2398 // all of the underlying nodes' info has been GC'ed
2399 return false;
2400 } // end has_previous_version()
2401
2402 methodOop instanceKlass::method_with_idnum(int idnum) {
2403 methodOop m = NULL;
2404 if (idnum < methods()->length()) {
2405 m = (methodOop) methods()->obj_at(idnum);
2406 }
2407 if (m == NULL || m->method_idnum() != idnum) {
2408 for (int index = 0; index < methods()->length(); ++index) {
2409 m = (methodOop) methods()->obj_at(index);
2410 if (m->method_idnum() == idnum) {
2411 return m;
2412 }
2413 }
2414 }
2415 return m;
2416 }
2417
2418
2419 // Set the annotation at 'idnum' to 'anno'.
2420 // We don't want to create or extend the array if 'anno' is NULL, since that is the
2421 // default value. However, if the array exists and is long enough, we must set NULL values.
2422 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
2423 objArrayOop md = *md_p;
2424 if (md != NULL && md->length() > idnum) {
2425 md->obj_at_put(idnum, anno);
2426 } else if (anno != NULL) {
2427 // create the array
2428 int length = MAX2(idnum+1, (int)_idnum_allocated_count);
2429 md = oopFactory::new_system_objArray(length, Thread::current());
2430 if (*md_p != NULL) {
2431 // copy the existing entries
2432 for (int index = 0; index < (*md_p)->length(); index++) {
2433 md->obj_at_put(index, (*md_p)->obj_at(index));
2434 }
2435 }
2436 set_annotations(md, md_p);
2437 md->obj_at_put(idnum, anno);
2438 } // if no array and idnum isn't included there is nothing to do
2439 }
2440
2441 // Construct a PreviousVersionNode entry for the array hung off
2442 // the instanceKlass.
2443 PreviousVersionNode::PreviousVersionNode(jweak prev_constant_pool,
2444 GrowableArray<jweak>* prev_EMCP_methods) {
2445
2446 _prev_constant_pool = prev_constant_pool;
2447 _prev_EMCP_methods = prev_EMCP_methods;
2448 }
2449
2450
2451 // Destroy a PreviousVersionNode
2452 PreviousVersionNode::~PreviousVersionNode() {
2453 if (_prev_constant_pool != NULL) {
2454 JNIHandles::destroy_weak_global(_prev_constant_pool);
2455 }
2456
2457 if (_prev_EMCP_methods != NULL) {
2458 for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
2459 jweak method_ref = _prev_EMCP_methods->at(i);
2460 if (method_ref != NULL) {
2461 JNIHandles::destroy_weak_global(method_ref);
2462 }
2463 }
2464 delete _prev_EMCP_methods;
2465 }
2466 }
2467
2468
2469 // Construct a PreviousVersionInfo entry
2470 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
2471 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
2472 _prev_EMCP_method_handles = NULL;
2473
2474 jweak cp_ref = pv_node->prev_constant_pool();
2475 assert(cp_ref != NULL, "weak constant pool ref was unexpectedly cleared");
2476 if (cp_ref == NULL) {
2477 return; // robustness
2478 }
2479
2480 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2481 if (cp == NULL) {
2482 // Weak reference has been GC'ed. Since the constant pool has been
2483 // GC'ed, the methods have also been GC'ed.
2484 return;
2485 }
2486
2487 // make the constantPoolOop safe to return
2488 _prev_constant_pool_handle = constantPoolHandle(cp);
2489
2490 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2491 if (method_refs == NULL) {
2492 // the instanceKlass did not have any EMCP methods
2493 return;
2494 }
2495
2496 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
2497
2498 int n_methods = method_refs->length();
2499 for (int i = 0; i < n_methods; i++) {
2500 jweak method_ref = method_refs->at(i);
2501 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2502 if (method_ref == NULL) {
2503 continue; // robustness
2504 }
2505
2506 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2507 if (method == NULL) {
2508 // this entry has been GC'ed so skip it
2509 continue;
2510 }
2511
2512 // make the methodOop safe to return
2513 _prev_EMCP_method_handles->append(methodHandle(method));
2514 }
2515 }
2516
2517
2518 // Destroy a PreviousVersionInfo
2519 PreviousVersionInfo::~PreviousVersionInfo() {
2520 // Since _prev_EMCP_method_handles is not C-heap allocated, we
2521 // don't have to delete it.
2522 }
2523
2524
2525 // Construct a helper for walking the previous versions array
2526 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
2527 _previous_versions = ik->previous_versions();
2528 _current_index = 0;
2529 // _hm needs no initialization
2530 _current_p = NULL;
2531 }
2532
2533
2534 // Destroy a PreviousVersionWalker
2535 PreviousVersionWalker::~PreviousVersionWalker() {
2536 // Delete the current info just in case the caller didn't walk to
2537 // the end of the previous versions list. No harm if _current_p is
2538 // already NULL.
2539 delete _current_p;
2540
2541 // When _hm is destroyed, all the Handles returned in
2542 // PreviousVersionInfo objects will be destroyed.
2543 // Also, after this destructor is finished it will be
2544 // safe to delete the GrowableArray allocated in the
2545 // PreviousVersionInfo objects.
2546 }
2547
2548
2549 // Return the interesting information for the next previous version
2550 // of the klass. Returns NULL if there are no more previous versions.
2551 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
2552 if (_previous_versions == NULL) {
2553 // no previous versions so nothing to return
2554 return NULL;
2555 }
2556
2557 delete _current_p; // cleanup the previous info for the caller
2558 _current_p = NULL; // reset to NULL so we don't delete same object twice
2559
2560 int length = _previous_versions->length();
2561
2562 while (_current_index < length) {
2563 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
2564 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
2565 PreviousVersionInfo(pv_node);
2566
2567 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
2568 if (cp_h.is_null()) {
2569 delete pv_info;
2570
2571 // The underlying node's info has been GC'ed so try the next one.
2572 // We don't have to check the methods. If the constant pool has
2573 // GC'ed then so have the methods.
2574 continue;
2575 }
2576
2577 // Found a node with non GC'ed info so return it. The caller will
2578 // need to delete pv_info when they are done with it.
2579 _current_p = pv_info;
2580 return pv_info;
2581 }
2582
2583 // all of the underlying nodes' info has been GC'ed
2584 return NULL;
2585 } // end next_previous_version()