Fri, 20 Mar 2009 23:19:36 -0700
6814659: separable cleanups and subroutines for 6655638
Summary: preparatory but separable changes for method handles
Reviewed-by: kvn, never
1 /*
2 * Copyright 1997-2009 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 */
25 # include "incls/_precompiled.incl"
26 # include "incls/_instanceKlass.cpp.incl"
28 bool instanceKlass::should_be_initialized() const {
29 return !is_initialized();
30 }
32 klassVtable* instanceKlass::vtable() const {
33 return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
34 }
36 klassItable* instanceKlass::itable() const {
37 return new klassItable(as_klassOop());
38 }
40 void instanceKlass::eager_initialize(Thread *thread) {
41 if (!EagerInitialization) return;
43 if (this->is_not_initialized()) {
44 // abort if the the class has a class initializer
45 if (this->class_initializer() != NULL) return;
47 // abort if it is java.lang.Object (initialization is handled in genesis)
48 klassOop super = this->super();
49 if (super == NULL) return;
51 // abort if the super class should be initialized
52 if (!instanceKlass::cast(super)->is_initialized()) return;
54 // call body to expose the this pointer
55 instanceKlassHandle this_oop(thread, this->as_klassOop());
56 eager_initialize_impl(this_oop);
57 }
58 }
61 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
62 EXCEPTION_MARK;
63 ObjectLocker ol(this_oop, THREAD);
65 // abort if someone beat us to the initialization
66 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
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.
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 }
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 }
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 }
117 // Used exclusively by the shared spaces dump mechanism to prevent
118 // classes mapped into the shared regions in new VMs from appearing linked.
120 void instanceKlass::unlink_class() {
121 assert(is_linked(), "must be linked");
122 _init_state = loaded;
123 }
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 }
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 }
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 }
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());
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 }
180 link_class_impl(super, throw_verifyerror, CHECK_false);
181 }
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 }
192 // in case the class is linked in the process of linking its superclasses
193 if (this_oop->is_linked()) {
194 return true;
195 }
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 }
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 }
225 // also sets rewritten
226 this_oop->rewrite_class(CHECK_false);
227 }
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 }
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.
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 }
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);
287 // refer to the JVM book page 47 for description of steps
288 // Step 1
289 { ObjectLocker ol(this_oop, THREAD);
291 Thread *self = THREAD; // it's passed the current thread
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 }
301 // Step 3
302 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self))
303 return;
305 // Step 4
306 if (this_oop->is_initialized())
307 return;
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 }
325 // Step 6
326 this_oop->set_init_state(being_initialized);
327 this_oop->set_init_thread(self);
328 }
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);
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 }
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 }
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 }
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 }
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 }
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;
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;
415 // Update number of implementors
416 int i = _nof_implementors++;
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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.
529 KlassHandle h_k(THREAD, as_klassOop());
531 instanceOop i;
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 }
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 }
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 }
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 }
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;
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);
582 // Check if update has already taken place
583 if (this_oop->array_klasses() == NULL) {
584 objArrayKlassKlass* oakk =
585 (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
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 }
600 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
601 return array_klass_impl(or_null, 1, THREAD);
602 }
604 void instanceKlass::call_class_initializer(TRAPS) {
605 instanceKlassHandle ik (THREAD, as_klassOop());
606 call_class_initializer_impl(ik, THREAD);
607 }
609 static int call_class_initializer_impl_counter = 0; // for debugging
611 methodOop instanceKlass::class_initializer() {
612 return find_method(vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
613 }
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 }
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 }
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 }
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);
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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 }
794 static int compare_fields_by_offset(int* a, int* b) {
795 return a[0] - b[0];
796 }
798 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
799 instanceKlass* super = superklass();
800 if (super != NULL) {
801 super->do_nonstatic_fields(cl);
802 }
803 fieldDescriptor fd;
804 int length = fields()->length();
805 // In DebugInfo nonstatic fields are sorted by offset.
806 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1));
807 int j = 0;
808 for (int i = 0; i < length; i += next_offset) {
809 fd.initialize(as_klassOop(), i);
810 if (!fd.is_static()) {
811 fields_sorted[j + 0] = fd.offset();
812 fields_sorted[j + 1] = i;
813 j += 2;
814 }
815 }
816 if (j > 0) {
817 length = j;
818 // _sort_Fn is defined in growableArray.hpp.
819 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
820 for (int i = 0; i < length; i += 2) {
821 fd.initialize(as_klassOop(), fields_sorted[i + 1]);
822 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
823 cl->do_field(&fd);
824 }
825 }
826 FREE_C_HEAP_ARRAY(int, fields_sorted);
827 }
830 void instanceKlass::array_klasses_do(void f(klassOop k)) {
831 if (array_klasses() != NULL)
832 arrayKlass::cast(array_klasses())->array_klasses_do(f);
833 }
836 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
837 f(as_klassOop());
838 array_klasses_do(f);
839 }
841 #ifdef ASSERT
842 static int linear_search(objArrayOop methods, symbolOop name, symbolOop signature) {
843 int len = methods->length();
844 for (int index = 0; index < len; index++) {
845 methodOop m = (methodOop)(methods->obj_at(index));
846 assert(m->is_method(), "must be method");
847 if (m->signature() == signature && m->name() == name) {
848 return index;
849 }
850 }
851 return -1;
852 }
853 #endif
855 methodOop instanceKlass::find_method(symbolOop name, symbolOop signature) const {
856 return instanceKlass::find_method(methods(), name, signature);
857 }
859 methodOop instanceKlass::find_method(objArrayOop methods, symbolOop name, symbolOop signature) {
860 int len = methods->length();
861 // methods are sorted, so do binary search
862 int l = 0;
863 int h = len - 1;
864 while (l <= h) {
865 int mid = (l + h) >> 1;
866 methodOop m = (methodOop)methods->obj_at(mid);
867 assert(m->is_method(), "must be method");
868 int res = m->name()->fast_compare(name);
869 if (res == 0) {
870 // found matching name; do linear search to find matching signature
871 // first, quick check for common case
872 if (m->signature() == signature) return m;
873 // search downwards through overloaded methods
874 int i;
875 for (i = mid - 1; i >= l; i--) {
876 methodOop m = (methodOop)methods->obj_at(i);
877 assert(m->is_method(), "must be method");
878 if (m->name() != name) break;
879 if (m->signature() == signature) return m;
880 }
881 // search upwards
882 for (i = mid + 1; i <= h; i++) {
883 methodOop m = (methodOop)methods->obj_at(i);
884 assert(m->is_method(), "must be method");
885 if (m->name() != name) break;
886 if (m->signature() == signature) return m;
887 }
888 // not found
889 #ifdef ASSERT
890 int index = linear_search(methods, name, signature);
891 if (index != -1) fatal1("binary search bug: should have found entry %d", index);
892 #endif
893 return NULL;
894 } else if (res < 0) {
895 l = mid + 1;
896 } else {
897 h = mid - 1;
898 }
899 }
900 #ifdef ASSERT
901 int index = linear_search(methods, name, signature);
902 if (index != -1) fatal1("binary search bug: should have found entry %d", index);
903 #endif
904 return NULL;
905 }
907 methodOop instanceKlass::uncached_lookup_method(symbolOop name, symbolOop signature) const {
908 klassOop klass = as_klassOop();
909 while (klass != NULL) {
910 methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
911 if (method != NULL) return method;
912 klass = instanceKlass::cast(klass)->super();
913 }
914 return NULL;
915 }
917 // lookup a method in all the interfaces that this class implements
918 methodOop instanceKlass::lookup_method_in_all_interfaces(symbolOop name,
919 symbolOop signature) const {
920 objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
921 int num_ifs = all_ifs->length();
922 instanceKlass *ik = NULL;
923 for (int i = 0; i < num_ifs; i++) {
924 ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
925 methodOop m = ik->lookup_method(name, signature);
926 if (m != NULL) {
927 return m;
928 }
929 }
930 return NULL;
931 }
933 /* jni_id_for_impl for jfieldIds only */
934 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
935 MutexLocker ml(JfieldIdCreation_lock);
936 // Retry lookup after we got the lock
937 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
938 if (probe == NULL) {
939 // Slow case, allocate new static field identifier
940 probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
941 this_oop->set_jni_ids(probe);
942 }
943 return probe;
944 }
947 /* jni_id_for for jfieldIds only */
948 JNIid* instanceKlass::jni_id_for(int offset) {
949 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
950 if (probe == NULL) {
951 probe = jni_id_for_impl(this->as_klassOop(), offset);
952 }
953 return probe;
954 }
957 // Lookup or create a jmethodID.
958 // This code can be called by the VM thread. For this reason it is critical that
959 // there are no blocking operations (safepoints) while the lock is held -- or a
960 // deadlock can occur.
961 jmethodID instanceKlass::jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h) {
962 size_t idnum = (size_t)method_h->method_idnum();
963 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
964 size_t length = 0;
965 jmethodID id = NULL;
966 // array length stored in first element, other elements offset by one
967 if (jmeths == NULL || // If there is no jmethodID array,
968 (length = (size_t)jmeths[0]) <= idnum || // or if it is too short,
969 (id = jmeths[idnum+1]) == NULL) { // or if this jmethodID isn't allocated
971 // Do all the safepointing things (allocations) before grabbing the lock.
972 // These allocations will have to be freed if they are unused.
974 // Allocate a new array of methods.
975 jmethodID* new_jmeths = NULL;
976 if (length <= idnum) {
977 // A new array will be needed (unless some other thread beats us to it)
978 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
979 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
980 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
981 new_jmeths[0] =(jmethodID)size; // array size held in the first element
982 }
984 // Allocate a new method ID.
985 jmethodID new_id = NULL;
986 if (method_h->is_old() && !method_h->is_obsolete()) {
987 // The method passed in is old (but not obsolete), we need to use the current version
988 methodOop current_method = ik_h->method_with_idnum((int)idnum);
989 assert(current_method != NULL, "old and but not obsolete, so should exist");
990 methodHandle current_method_h(current_method == NULL? method_h() : current_method);
991 new_id = JNIHandles::make_jmethod_id(current_method_h);
992 } else {
993 // It is the current version of the method or an obsolete method,
994 // use the version passed in
995 new_id = JNIHandles::make_jmethod_id(method_h);
996 }
998 if (Threads::number_of_threads() == 0 || SafepointSynchronize::is_at_safepoint()) {
999 // No need and unsafe to lock the JmethodIdCreation_lock at safepoint.
1000 id = get_jmethod_id(ik_h, idnum, new_id, new_jmeths);
1001 } else {
1002 MutexLocker ml(JmethodIdCreation_lock);
1003 id = get_jmethod_id(ik_h, idnum, new_id, new_jmeths);
1004 }
1005 }
1006 return id;
1007 }
1010 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, size_t idnum,
1011 jmethodID new_id, jmethodID* new_jmeths) {
1012 // Retry lookup after we got the lock or ensured we are at safepoint
1013 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1014 jmethodID id = NULL;
1015 jmethodID to_dealloc_id = NULL;
1016 jmethodID* to_dealloc_jmeths = NULL;
1017 size_t length;
1019 if (jmeths == NULL || (length = (size_t)jmeths[0]) <= idnum) {
1020 if (jmeths != NULL) {
1021 // We have grown the array: copy the existing entries, and delete the old array
1022 for (size_t index = 0; index < length; index++) {
1023 new_jmeths[index+1] = jmeths[index+1];
1024 }
1025 to_dealloc_jmeths = jmeths; // using the new jmeths, deallocate the old one
1026 }
1027 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1028 } else {
1029 id = jmeths[idnum+1];
1030 to_dealloc_jmeths = new_jmeths; // using the old jmeths, deallocate the new one
1031 }
1032 if (id == NULL) {
1033 id = new_id;
1034 jmeths[idnum+1] = id; // install the new method ID
1035 } else {
1036 to_dealloc_id = new_id; // the new id wasn't used, mark it for deallocation
1037 }
1039 // Free up unneeded or no longer needed resources
1040 FreeHeap(to_dealloc_jmeths);
1041 if (to_dealloc_id != NULL) {
1042 JNIHandles::destroy_jmethod_id(to_dealloc_id);
1043 }
1044 return id;
1045 }
1048 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1049 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
1050 size_t idnum = (size_t)method->method_idnum();
1051 jmethodID* jmeths = methods_jmethod_ids_acquire();
1052 size_t length; // length assigned as debugging crumb
1053 jmethodID id = NULL;
1054 if (jmeths != NULL && // If there is a jmethodID array,
1055 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1056 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1057 }
1058 return id;
1059 }
1062 // Cache an itable index
1063 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
1064 int* indices = methods_cached_itable_indices_acquire();
1065 if (indices == NULL || // If there is no index array,
1066 ((size_t)indices[0]) <= idnum) { // or if it is too short
1067 // Lock before we allocate the array so we don't leak
1068 MutexLocker ml(JNICachedItableIndex_lock);
1069 // Retry lookup after we got the lock
1070 indices = methods_cached_itable_indices_acquire();
1071 size_t length = 0;
1072 // array length stored in first element, other elements offset by one
1073 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1074 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1075 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
1076 // Copy the existing entries, if any
1077 size_t i;
1078 for (i = 0; i < length; i++) {
1079 new_indices[i+1] = indices[i+1];
1080 }
1081 // Set all the rest to -1
1082 for (i = length; i < size; i++) {
1083 new_indices[i+1] = -1;
1084 }
1085 if (indices != NULL) {
1086 FreeHeap(indices); // delete any old indices
1087 }
1088 release_set_methods_cached_itable_indices(indices = new_indices);
1089 }
1090 } else {
1091 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1092 }
1093 // This is a cache, if there is a race to set it, it doesn't matter
1094 indices[idnum+1] = index;
1095 }
1098 // Retrieve a cached itable index
1099 int instanceKlass::cached_itable_index(size_t idnum) {
1100 int* indices = methods_cached_itable_indices_acquire();
1101 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1102 // indices exist and are long enough, retrieve possible cached
1103 return indices[idnum+1];
1104 }
1105 return -1;
1106 }
1109 //
1110 // nmethodBucket is used to record dependent nmethods for
1111 // deoptimization. nmethod dependencies are actually <klass, method>
1112 // pairs but we really only care about the klass part for purposes of
1113 // finding nmethods which might need to be deoptimized. Instead of
1114 // recording the method, a count of how many times a particular nmethod
1115 // was recorded is kept. This ensures that any recording errors are
1116 // noticed since an nmethod should be removed as many times are it's
1117 // added.
1118 //
1119 class nmethodBucket {
1120 private:
1121 nmethod* _nmethod;
1122 int _count;
1123 nmethodBucket* _next;
1125 public:
1126 nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1127 _nmethod = nmethod;
1128 _next = next;
1129 _count = 1;
1130 }
1131 int count() { return _count; }
1132 int increment() { _count += 1; return _count; }
1133 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
1134 nmethodBucket* next() { return _next; }
1135 void set_next(nmethodBucket* b) { _next = b; }
1136 nmethod* get_nmethod() { return _nmethod; }
1137 };
1140 //
1141 // Walk the list of dependent nmethods searching for nmethods which
1142 // are dependent on the klassOop that was passed in and mark them for
1143 // deoptimization. Returns the number of nmethods found.
1144 //
1145 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
1146 assert_locked_or_safepoint(CodeCache_lock);
1147 int found = 0;
1148 nmethodBucket* b = _dependencies;
1149 while (b != NULL) {
1150 nmethod* nm = b->get_nmethod();
1151 // since dependencies aren't removed until an nmethod becomes a zombie,
1152 // the dependency list may contain nmethods which aren't alive.
1153 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1154 if (TraceDependencies) {
1155 ResourceMark rm;
1156 tty->print_cr("Marked for deoptimization");
1157 tty->print_cr(" context = %s", this->external_name());
1158 changes.print();
1159 nm->print();
1160 nm->print_dependencies();
1161 }
1162 nm->mark_for_deoptimization();
1163 found++;
1164 }
1165 b = b->next();
1166 }
1167 return found;
1168 }
1171 //
1172 // Add an nmethodBucket to the list of dependencies for this nmethod.
1173 // It's possible that an nmethod has multiple dependencies on this klass
1174 // so a count is kept for each bucket to guarantee that creation and
1175 // deletion of dependencies is consistent.
1176 //
1177 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
1178 assert_locked_or_safepoint(CodeCache_lock);
1179 nmethodBucket* b = _dependencies;
1180 nmethodBucket* last = NULL;
1181 while (b != NULL) {
1182 if (nm == b->get_nmethod()) {
1183 b->increment();
1184 return;
1185 }
1186 b = b->next();
1187 }
1188 _dependencies = new nmethodBucket(nm, _dependencies);
1189 }
1192 //
1193 // Decrement count of the nmethod in the dependency list and remove
1194 // the bucket competely when the count goes to 0. This method must
1195 // find a corresponding bucket otherwise there's a bug in the
1196 // recording of dependecies.
1197 //
1198 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
1199 assert_locked_or_safepoint(CodeCache_lock);
1200 nmethodBucket* b = _dependencies;
1201 nmethodBucket* last = NULL;
1202 while (b != NULL) {
1203 if (nm == b->get_nmethod()) {
1204 if (b->decrement() == 0) {
1205 if (last == NULL) {
1206 _dependencies = b->next();
1207 } else {
1208 last->set_next(b->next());
1209 }
1210 delete b;
1211 }
1212 return;
1213 }
1214 last = b;
1215 b = b->next();
1216 }
1217 #ifdef ASSERT
1218 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1219 nm->print();
1220 #endif // ASSERT
1221 ShouldNotReachHere();
1222 }
1225 #ifndef PRODUCT
1226 void instanceKlass::print_dependent_nmethods(bool verbose) {
1227 nmethodBucket* b = _dependencies;
1228 int idx = 0;
1229 while (b != NULL) {
1230 nmethod* nm = b->get_nmethod();
1231 tty->print("[%d] count=%d { ", idx++, b->count());
1232 if (!verbose) {
1233 nm->print_on(tty, "nmethod");
1234 tty->print_cr(" } ");
1235 } else {
1236 nm->print();
1237 nm->print_dependencies();
1238 tty->print_cr("--- } ");
1239 }
1240 b = b->next();
1241 }
1242 }
1245 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
1246 nmethodBucket* b = _dependencies;
1247 while (b != NULL) {
1248 if (nm == b->get_nmethod()) {
1249 return true;
1250 }
1251 b = b->next();
1252 }
1253 return false;
1254 }
1255 #endif //PRODUCT
1258 #ifdef ASSERT
1259 template <class T> void assert_is_in(T *p) {
1260 T heap_oop = oopDesc::load_heap_oop(p);
1261 if (!oopDesc::is_null(heap_oop)) {
1262 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1263 assert(Universe::heap()->is_in(o), "should be in heap");
1264 }
1265 }
1266 template <class T> void assert_is_in_closed_subset(T *p) {
1267 T heap_oop = oopDesc::load_heap_oop(p);
1268 if (!oopDesc::is_null(heap_oop)) {
1269 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1270 assert(Universe::heap()->is_in_closed_subset(o), "should be in closed");
1271 }
1272 }
1273 template <class T> void assert_is_in_reserved(T *p) {
1274 T heap_oop = oopDesc::load_heap_oop(p);
1275 if (!oopDesc::is_null(heap_oop)) {
1276 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1277 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1278 }
1279 }
1280 template <class T> void assert_nothing(T *p) {}
1282 #else
1283 template <class T> void assert_is_in(T *p) {}
1284 template <class T> void assert_is_in_closed_subset(T *p) {}
1285 template <class T> void assert_is_in_reserved(T *p) {}
1286 template <class T> void assert_nothing(T *p) {}
1287 #endif // ASSERT
1289 //
1290 // Macros that iterate over areas of oops which are specialized on type of
1291 // oop pointer either narrow or wide, depending on UseCompressedOops
1292 //
1293 // Parameters are:
1294 // T - type of oop to point to (either oop or narrowOop)
1295 // start_p - starting pointer for region to iterate over
1296 // count - number of oops or narrowOops to iterate over
1297 // do_oop - action to perform on each oop (it's arbitrary C code which
1298 // makes it more efficient to put in a macro rather than making
1299 // it a template function)
1300 // assert_fn - assert function which is template function because performance
1301 // doesn't matter when enabled.
1302 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1303 T, start_p, count, do_oop, \
1304 assert_fn) \
1305 { \
1306 T* p = (T*)(start_p); \
1307 T* const end = p + (count); \
1308 while (p < end) { \
1309 (assert_fn)(p); \
1310 do_oop; \
1311 ++p; \
1312 } \
1313 }
1315 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1316 T, start_p, count, do_oop, \
1317 assert_fn) \
1318 { \
1319 T* const start = (T*)(start_p); \
1320 T* p = start + (count); \
1321 while (start < p) { \
1322 --p; \
1323 (assert_fn)(p); \
1324 do_oop; \
1325 } \
1326 }
1328 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1329 T, start_p, count, low, high, \
1330 do_oop, assert_fn) \
1331 { \
1332 T* const l = (T*)(low); \
1333 T* const h = (T*)(high); \
1334 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1335 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1336 "bounded region must be properly aligned"); \
1337 T* p = (T*)(start_p); \
1338 T* end = p + (count); \
1339 if (p < l) p = l; \
1340 if (end > h) end = h; \
1341 while (p < end) { \
1342 (assert_fn)(p); \
1343 do_oop; \
1344 ++p; \
1345 } \
1346 }
1349 // The following macros call specialized macros, passing either oop or
1350 // narrowOop as the specialization type. These test the UseCompressedOops
1351 // flag.
1352 #define InstanceKlass_OOP_ITERATE(start_p, count, \
1353 do_oop, assert_fn) \
1354 { \
1355 if (UseCompressedOops) { \
1356 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1357 start_p, count, \
1358 do_oop, assert_fn) \
1359 } else { \
1360 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1361 start_p, count, \
1362 do_oop, assert_fn) \
1363 } \
1364 }
1366 #define InstanceKlass_BOUNDED_OOP_ITERATE(start_p, count, low, high, \
1367 do_oop, assert_fn) \
1368 { \
1369 if (UseCompressedOops) { \
1370 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
1371 start_p, count, \
1372 low, high, \
1373 do_oop, assert_fn) \
1374 } else { \
1375 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
1376 start_p, count, \
1377 low, high, \
1378 do_oop, assert_fn) \
1379 } \
1380 }
1382 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
1383 { \
1384 /* Compute oopmap block range. The common case \
1385 is nonstatic_oop_map_size == 1. */ \
1386 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1387 OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \
1388 if (UseCompressedOops) { \
1389 while (map < end_map) { \
1390 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1391 obj->obj_field_addr<narrowOop>(map->offset()), map->length(), \
1392 do_oop, assert_fn) \
1393 ++map; \
1394 } \
1395 } else { \
1396 while (map < end_map) { \
1397 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1398 obj->obj_field_addr<oop>(map->offset()), map->length(), \
1399 do_oop, assert_fn) \
1400 ++map; \
1401 } \
1402 } \
1403 }
1405 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
1406 { \
1407 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
1408 OopMapBlock* map = start_map + nonstatic_oop_map_size(); \
1409 if (UseCompressedOops) { \
1410 while (start_map < map) { \
1411 --map; \
1412 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
1413 obj->obj_field_addr<narrowOop>(map->offset()), map->length(), \
1414 do_oop, assert_fn) \
1415 } \
1416 } else { \
1417 while (start_map < map) { \
1418 --map; \
1419 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
1420 obj->obj_field_addr<oop>(map->offset()), map->length(), \
1421 do_oop, assert_fn) \
1422 } \
1423 } \
1424 }
1426 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
1427 assert_fn) \
1428 { \
1429 /* Compute oopmap block range. The common case is \
1430 nonstatic_oop_map_size == 1, so we accept the \
1431 usually non-existent extra overhead of examining \
1432 all the maps. */ \
1433 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1434 OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \
1435 if (UseCompressedOops) { \
1436 while (map < end_map) { \
1437 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
1438 obj->obj_field_addr<narrowOop>(map->offset()), map->length(), \
1439 low, high, \
1440 do_oop, assert_fn) \
1441 ++map; \
1442 } \
1443 } else { \
1444 while (map < end_map) { \
1445 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
1446 obj->obj_field_addr<oop>(map->offset()), map->length(), \
1447 low, high, \
1448 do_oop, assert_fn) \
1449 ++map; \
1450 } \
1451 } \
1452 }
1454 void instanceKlass::follow_static_fields() {
1455 InstanceKlass_OOP_ITERATE( \
1456 start_of_static_fields(), static_oop_field_size(), \
1457 MarkSweep::mark_and_push(p), \
1458 assert_is_in_closed_subset)
1459 }
1461 #ifndef SERIALGC
1462 void instanceKlass::follow_static_fields(ParCompactionManager* cm) {
1463 InstanceKlass_OOP_ITERATE( \
1464 start_of_static_fields(), static_oop_field_size(), \
1465 PSParallelCompact::mark_and_push(cm, p), \
1466 assert_is_in)
1467 }
1468 #endif // SERIALGC
1470 void instanceKlass::adjust_static_fields() {
1471 InstanceKlass_OOP_ITERATE( \
1472 start_of_static_fields(), static_oop_field_size(), \
1473 MarkSweep::adjust_pointer(p), \
1474 assert_nothing)
1475 }
1477 #ifndef SERIALGC
1478 void instanceKlass::update_static_fields() {
1479 InstanceKlass_OOP_ITERATE( \
1480 start_of_static_fields(), static_oop_field_size(), \
1481 PSParallelCompact::adjust_pointer(p), \
1482 assert_nothing)
1483 }
1485 void instanceKlass::update_static_fields(HeapWord* beg_addr, HeapWord* end_addr) {
1486 InstanceKlass_BOUNDED_OOP_ITERATE( \
1487 start_of_static_fields(), static_oop_field_size(), \
1488 beg_addr, end_addr, \
1489 PSParallelCompact::adjust_pointer(p), \
1490 assert_nothing )
1491 }
1492 #endif // SERIALGC
1494 void instanceKlass::oop_follow_contents(oop obj) {
1495 assert(obj != NULL, "can't follow the content of NULL object");
1496 obj->follow_header();
1497 InstanceKlass_OOP_MAP_ITERATE( \
1498 obj, \
1499 MarkSweep::mark_and_push(p), \
1500 assert_is_in_closed_subset)
1501 }
1503 #ifndef SERIALGC
1504 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
1505 oop obj) {
1506 assert(obj != NULL, "can't follow the content of NULL object");
1507 obj->follow_header(cm);
1508 InstanceKlass_OOP_MAP_ITERATE( \
1509 obj, \
1510 PSParallelCompact::mark_and_push(cm, p), \
1511 assert_is_in)
1512 }
1513 #endif // SERIALGC
1515 // closure's do_header() method dicates whether the given closure should be
1516 // applied to the klass ptr in the object header.
1518 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
1519 \
1520 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
1521 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1522 /* header */ \
1523 if (closure->do_header()) { \
1524 obj->oop_iterate_header(closure); \
1525 } \
1526 InstanceKlass_OOP_MAP_ITERATE( \
1527 obj, \
1528 SpecializationStats:: \
1529 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
1530 (closure)->do_oop##nv_suffix(p), \
1531 assert_is_in_closed_subset) \
1532 return size_helper(); \
1533 }
1535 #ifndef SERIALGC
1536 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
1537 \
1538 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
1539 OopClosureType* closure) { \
1540 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
1541 /* header */ \
1542 if (closure->do_header()) { \
1543 obj->oop_iterate_header(closure); \
1544 } \
1545 /* instance variables */ \
1546 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1547 obj, \
1548 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
1549 (closure)->do_oop##nv_suffix(p), \
1550 assert_is_in_closed_subset) \
1551 return size_helper(); \
1552 }
1553 #endif // !SERIALGC
1555 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
1556 \
1557 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
1558 OopClosureType* closure, \
1559 MemRegion mr) { \
1560 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1561 if (closure->do_header()) { \
1562 obj->oop_iterate_header(closure, mr); \
1563 } \
1564 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
1565 obj, mr.start(), mr.end(), \
1566 (closure)->do_oop##nv_suffix(p), \
1567 assert_is_in_closed_subset) \
1568 return size_helper(); \
1569 }
1571 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1572 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1573 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1574 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1575 #ifndef SERIALGC
1576 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1577 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1578 #endif // !SERIALGC
1580 void instanceKlass::iterate_static_fields(OopClosure* closure) {
1581 InstanceKlass_OOP_ITERATE( \
1582 start_of_static_fields(), static_oop_field_size(), \
1583 closure->do_oop(p), \
1584 assert_is_in_reserved)
1585 }
1587 void instanceKlass::iterate_static_fields(OopClosure* closure,
1588 MemRegion mr) {
1589 InstanceKlass_BOUNDED_OOP_ITERATE( \
1590 start_of_static_fields(), static_oop_field_size(), \
1591 mr.start(), mr.end(), \
1592 (closure)->do_oop_v(p), \
1593 assert_is_in_closed_subset)
1594 }
1596 int instanceKlass::oop_adjust_pointers(oop obj) {
1597 int size = size_helper();
1598 InstanceKlass_OOP_MAP_ITERATE( \
1599 obj, \
1600 MarkSweep::adjust_pointer(p), \
1601 assert_is_in)
1602 obj->adjust_header();
1603 return size;
1604 }
1606 #ifndef SERIALGC
1607 void instanceKlass::oop_copy_contents(PSPromotionManager* pm, oop obj) {
1608 assert(!pm->depth_first(), "invariant");
1609 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1610 obj, \
1611 if (PSScavenge::should_scavenge(p)) { \
1612 pm->claim_or_forward_breadth(p); \
1613 }, \
1614 assert_nothing )
1615 }
1617 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
1618 assert(pm->depth_first(), "invariant");
1619 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1620 obj, \
1621 if (PSScavenge::should_scavenge(p)) { \
1622 pm->claim_or_forward_depth(p); \
1623 }, \
1624 assert_nothing )
1625 }
1627 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
1628 InstanceKlass_OOP_MAP_ITERATE( \
1629 obj, \
1630 PSParallelCompact::adjust_pointer(p), \
1631 assert_nothing)
1632 return size_helper();
1633 }
1635 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj,
1636 HeapWord* beg_addr, HeapWord* end_addr) {
1637 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
1638 obj, beg_addr, end_addr, \
1639 PSParallelCompact::adjust_pointer(p), \
1640 assert_nothing)
1641 return size_helper();
1642 }
1644 void instanceKlass::copy_static_fields(PSPromotionManager* pm) {
1645 assert(!pm->depth_first(), "invariant");
1646 InstanceKlass_OOP_ITERATE( \
1647 start_of_static_fields(), static_oop_field_size(), \
1648 if (PSScavenge::should_scavenge(p)) { \
1649 pm->claim_or_forward_breadth(p); \
1650 }, \
1651 assert_nothing )
1652 }
1654 void instanceKlass::push_static_fields(PSPromotionManager* pm) {
1655 assert(pm->depth_first(), "invariant");
1656 InstanceKlass_OOP_ITERATE( \
1657 start_of_static_fields(), static_oop_field_size(), \
1658 if (PSScavenge::should_scavenge(p)) { \
1659 pm->claim_or_forward_depth(p); \
1660 }, \
1661 assert_nothing )
1662 }
1664 void instanceKlass::copy_static_fields(ParCompactionManager* cm) {
1665 InstanceKlass_OOP_ITERATE( \
1666 start_of_static_fields(), static_oop_field_size(), \
1667 PSParallelCompact::adjust_pointer(p), \
1668 assert_is_in)
1669 }
1670 #endif // SERIALGC
1672 // This klass is alive but the implementor link is not followed/updated.
1673 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
1675 void instanceKlass::follow_weak_klass_links(
1676 BoolObjectClosure* is_alive, OopClosure* keep_alive) {
1677 assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
1678 if (ClassUnloading) {
1679 for (int i = 0; i < implementors_limit; i++) {
1680 klassOop impl = _implementors[i];
1681 if (impl == NULL) break; // no more in the list
1682 if (!is_alive->do_object_b(impl)) {
1683 // remove this guy from the list by overwriting him with the tail
1684 int lasti = --_nof_implementors;
1685 assert(lasti >= i && lasti < implementors_limit, "just checking");
1686 _implementors[i] = _implementors[lasti];
1687 _implementors[lasti] = NULL;
1688 --i; // rerun the loop at this index
1689 }
1690 }
1691 } else {
1692 for (int i = 0; i < implementors_limit; i++) {
1693 keep_alive->do_oop(&adr_implementors()[i]);
1694 }
1695 }
1696 Klass::follow_weak_klass_links(is_alive, keep_alive);
1697 }
1699 void instanceKlass::remove_unshareable_info() {
1700 Klass::remove_unshareable_info();
1701 init_implementor();
1702 }
1704 static void clear_all_breakpoints(methodOop m) {
1705 m->clear_all_breakpoints();
1706 }
1708 void instanceKlass::release_C_heap_structures() {
1709 // Deallocate oop map cache
1710 if (_oop_map_cache != NULL) {
1711 delete _oop_map_cache;
1712 _oop_map_cache = NULL;
1713 }
1715 // Deallocate JNI identifiers for jfieldIDs
1716 JNIid::deallocate(jni_ids());
1717 set_jni_ids(NULL);
1719 jmethodID* jmeths = methods_jmethod_ids_acquire();
1720 if (jmeths != (jmethodID*)NULL) {
1721 release_set_methods_jmethod_ids(NULL);
1722 FreeHeap(jmeths);
1723 }
1725 int* indices = methods_cached_itable_indices_acquire();
1726 if (indices != (int*)NULL) {
1727 release_set_methods_cached_itable_indices(NULL);
1728 FreeHeap(indices);
1729 }
1731 // release dependencies
1732 nmethodBucket* b = _dependencies;
1733 _dependencies = NULL;
1734 while (b != NULL) {
1735 nmethodBucket* next = b->next();
1736 delete b;
1737 b = next;
1738 }
1740 // Deallocate breakpoint records
1741 if (breakpoints() != 0x0) {
1742 methods_do(clear_all_breakpoints);
1743 assert(breakpoints() == 0x0, "should have cleared breakpoints");
1744 }
1746 // deallocate information about previous versions
1747 if (_previous_versions != NULL) {
1748 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
1749 PreviousVersionNode * pv_node = _previous_versions->at(i);
1750 delete pv_node;
1751 }
1752 delete _previous_versions;
1753 _previous_versions = NULL;
1754 }
1756 // deallocate the cached class file
1757 if (_cached_class_file_bytes != NULL) {
1758 os::free(_cached_class_file_bytes);
1759 _cached_class_file_bytes = NULL;
1760 _cached_class_file_len = 0;
1761 }
1762 }
1764 char* instanceKlass::signature_name() const {
1765 const char* src = (const char*) (name()->as_C_string());
1766 const int src_length = (int)strlen(src);
1767 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
1768 int src_index = 0;
1769 int dest_index = 0;
1770 dest[dest_index++] = 'L';
1771 while (src_index < src_length) {
1772 dest[dest_index++] = src[src_index++];
1773 }
1774 dest[dest_index++] = ';';
1775 dest[dest_index] = '\0';
1776 return dest;
1777 }
1779 // different verisons of is_same_class_package
1780 bool instanceKlass::is_same_class_package(klassOop class2) {
1781 klassOop class1 = as_klassOop();
1782 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1783 symbolOop classname1 = Klass::cast(class1)->name();
1785 if (Klass::cast(class2)->oop_is_objArray()) {
1786 class2 = objArrayKlass::cast(class2)->bottom_klass();
1787 }
1788 oop classloader2;
1789 if (Klass::cast(class2)->oop_is_instance()) {
1790 classloader2 = instanceKlass::cast(class2)->class_loader();
1791 } else {
1792 assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
1793 classloader2 = NULL;
1794 }
1795 symbolOop classname2 = Klass::cast(class2)->name();
1797 return instanceKlass::is_same_class_package(classloader1, classname1,
1798 classloader2, classname2);
1799 }
1801 bool instanceKlass::is_same_class_package(oop classloader2, symbolOop classname2) {
1802 klassOop class1 = as_klassOop();
1803 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1804 symbolOop classname1 = Klass::cast(class1)->name();
1806 return instanceKlass::is_same_class_package(classloader1, classname1,
1807 classloader2, classname2);
1808 }
1810 // return true if two classes are in the same package, classloader
1811 // and classname information is enough to determine a class's package
1812 bool instanceKlass::is_same_class_package(oop class_loader1, symbolOop class_name1,
1813 oop class_loader2, symbolOop class_name2) {
1814 if (class_loader1 != class_loader2) {
1815 return false;
1816 } else if (class_name1 == class_name2) {
1817 return true; // skip painful bytewise comparison
1818 } else {
1819 ResourceMark rm;
1821 // The symbolOop's are in UTF8 encoding. Since we only need to check explicitly
1822 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
1823 // Otherwise, we just compare jbyte values between the strings.
1824 jbyte *name1 = class_name1->base();
1825 jbyte *name2 = class_name2->base();
1827 jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
1828 jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
1830 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
1831 // One of the two doesn't have a package. Only return true
1832 // if the other one also doesn't have a package.
1833 return last_slash1 == last_slash2;
1834 } else {
1835 // Skip over '['s
1836 if (*name1 == '[') {
1837 do {
1838 name1++;
1839 } while (*name1 == '[');
1840 if (*name1 != 'L') {
1841 // Something is terribly wrong. Shouldn't be here.
1842 return false;
1843 }
1844 }
1845 if (*name2 == '[') {
1846 do {
1847 name2++;
1848 } while (*name2 == '[');
1849 if (*name2 != 'L') {
1850 // Something is terribly wrong. Shouldn't be here.
1851 return false;
1852 }
1853 }
1855 // Check that package part is identical
1856 int length1 = last_slash1 - name1;
1857 int length2 = last_slash2 - name2;
1859 return UTF8::equal(name1, length1, name2, length2);
1860 }
1861 }
1862 }
1864 /* defined for now in jvm.cpp, for historical reasons *--
1865 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
1866 symbolOop& simple_name_result, TRAPS) {
1867 ...
1868 }
1869 */
1871 // tell if two classes have the same enclosing class (at package level)
1872 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
1873 klassOop class2_oop, TRAPS) {
1874 if (class2_oop == class1->as_klassOop()) return true;
1875 if (!Klass::cast(class2_oop)->oop_is_instance()) return false;
1876 instanceKlassHandle class2(THREAD, class2_oop);
1878 // must be in same package before we try anything else
1879 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
1880 return false;
1882 // As long as there is an outer1.getEnclosingClass,
1883 // shift the search outward.
1884 instanceKlassHandle outer1 = class1;
1885 for (;;) {
1886 // As we walk along, look for equalities between outer1 and class2.
1887 // Eventually, the walks will terminate as outer1 stops
1888 // at the top-level class around the original class.
1889 symbolOop ignore_name;
1890 klassOop next = outer1->compute_enclosing_class(ignore_name, CHECK_false);
1891 if (next == NULL) break;
1892 if (next == class2()) return true;
1893 outer1 = instanceKlassHandle(THREAD, next);
1894 }
1896 // Now do the same for class2.
1897 instanceKlassHandle outer2 = class2;
1898 for (;;) {
1899 symbolOop ignore_name;
1900 klassOop next = outer2->compute_enclosing_class(ignore_name, CHECK_false);
1901 if (next == NULL) break;
1902 // Might as well check the new outer against all available values.
1903 if (next == class1()) return true;
1904 if (next == outer1()) return true;
1905 outer2 = instanceKlassHandle(THREAD, next);
1906 }
1908 // If by this point we have not found an equality between the
1909 // two classes, we know they are in separate package members.
1910 return false;
1911 }
1914 jint instanceKlass::compute_modifier_flags(TRAPS) const {
1915 klassOop k = as_klassOop();
1916 jint access = access_flags().as_int();
1918 // But check if it happens to be member class.
1919 typeArrayOop inner_class_list = inner_classes();
1920 int length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
1921 assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
1922 if (length > 0) {
1923 typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
1924 instanceKlassHandle ik(THREAD, k);
1925 for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
1926 int ioff = inner_class_list_h->ushort_at(
1927 i + instanceKlass::inner_class_inner_class_info_offset);
1929 // Inner class attribute can be zero, skip it.
1930 // Strange but true: JVM spec. allows null inner class refs.
1931 if (ioff == 0) continue;
1933 // only look at classes that are already loaded
1934 // since we are looking for the flags for our self.
1935 symbolOop inner_name = ik->constants()->klass_name_at(ioff);
1936 if ((ik->name() == inner_name)) {
1937 // This is really a member class.
1938 access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset);
1939 break;
1940 }
1941 }
1942 }
1943 // Remember to strip ACC_SUPER bit
1944 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
1945 }
1947 jint instanceKlass::jvmti_class_status() const {
1948 jint result = 0;
1950 if (is_linked()) {
1951 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
1952 }
1954 if (is_initialized()) {
1955 assert(is_linked(), "Class status is not consistent");
1956 result |= JVMTI_CLASS_STATUS_INITIALIZED;
1957 }
1958 if (is_in_error_state()) {
1959 result |= JVMTI_CLASS_STATUS_ERROR;
1960 }
1961 return result;
1962 }
1964 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
1965 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
1966 int method_table_offset_in_words = ioe->offset()/wordSize;
1967 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
1968 / itableOffsetEntry::size();
1970 for (int cnt = 0 ; ; cnt ++, ioe ++) {
1971 // If the interface isn't implemented by the receiver class,
1972 // the VM should throw IncompatibleClassChangeError.
1973 if (cnt >= nof_interfaces) {
1974 THROW_OOP_0(vmSymbols::java_lang_IncompatibleClassChangeError());
1975 }
1977 klassOop ik = ioe->interface_klass();
1978 if (ik == holder) break;
1979 }
1981 itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
1982 methodOop m = ime[index].method();
1983 if (m == NULL) {
1984 THROW_OOP_0(vmSymbols::java_lang_AbstractMethodError());
1985 }
1986 return m;
1987 }
1989 // On-stack replacement stuff
1990 void instanceKlass::add_osr_nmethod(nmethod* n) {
1991 // only one compilation can be active
1992 NEEDS_CLEANUP
1993 // This is a short non-blocking critical region, so the no safepoint check is ok.
1994 OsrList_lock->lock_without_safepoint_check();
1995 assert(n->is_osr_method(), "wrong kind of nmethod");
1996 n->set_link(osr_nmethods_head());
1997 set_osr_nmethods_head(n);
1998 // Remember to unlock again
1999 OsrList_lock->unlock();
2000 }
2003 void instanceKlass::remove_osr_nmethod(nmethod* n) {
2004 // This is a short non-blocking critical region, so the no safepoint check is ok.
2005 OsrList_lock->lock_without_safepoint_check();
2006 assert(n->is_osr_method(), "wrong kind of nmethod");
2007 nmethod* last = NULL;
2008 nmethod* cur = osr_nmethods_head();
2009 // Search for match
2010 while(cur != NULL && cur != n) {
2011 last = cur;
2012 cur = cur->link();
2013 }
2014 if (cur == n) {
2015 if (last == NULL) {
2016 // Remove first element
2017 set_osr_nmethods_head(osr_nmethods_head()->link());
2018 } else {
2019 last->set_link(cur->link());
2020 }
2021 }
2022 n->set_link(NULL);
2023 // Remember to unlock again
2024 OsrList_lock->unlock();
2025 }
2027 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci) const {
2028 // This is a short non-blocking critical region, so the no safepoint check is ok.
2029 OsrList_lock->lock_without_safepoint_check();
2030 nmethod* osr = osr_nmethods_head();
2031 while (osr != NULL) {
2032 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2033 if (osr->method() == m &&
2034 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2035 // Found a match - return it.
2036 OsrList_lock->unlock();
2037 return osr;
2038 }
2039 osr = osr->link();
2040 }
2041 OsrList_lock->unlock();
2042 return NULL;
2043 }
2045 // -----------------------------------------------------------------------------------------------------
2046 #ifndef PRODUCT
2048 // Printing
2050 #define BULLET " - "
2052 void FieldPrinter::do_field(fieldDescriptor* fd) {
2053 _st->print(BULLET);
2054 if (fd->is_static() || (_obj == NULL)) {
2055 fd->print_on(_st);
2056 _st->cr();
2057 } else {
2058 fd->print_on_for(_st, _obj);
2059 _st->cr();
2060 }
2061 }
2064 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
2065 Klass::oop_print_on(obj, st);
2067 if (as_klassOop() == SystemDictionary::string_klass()) {
2068 typeArrayOop value = java_lang_String::value(obj);
2069 juint offset = java_lang_String::offset(obj);
2070 juint length = java_lang_String::length(obj);
2071 if (value != NULL &&
2072 value->is_typeArray() &&
2073 offset <= (juint) value->length() &&
2074 offset + length <= (juint) value->length()) {
2075 st->print(BULLET"string: ");
2076 Handle h_obj(obj);
2077 java_lang_String::print(h_obj, st);
2078 st->cr();
2079 if (!WizardMode) return; // that is enough
2080 }
2081 }
2083 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2084 FieldPrinter print_nonstatic_field(st, obj);
2085 do_nonstatic_fields(&print_nonstatic_field);
2087 if (as_klassOop() == SystemDictionary::class_klass()) {
2088 st->print(BULLET"signature: ");
2089 java_lang_Class::print_signature(obj, st);
2090 st->cr();
2091 klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
2092 st->print(BULLET"fake entry for mirror: ");
2093 mirrored_klass->print_value_on(st);
2094 st->cr();
2095 st->print(BULLET"fake entry resolved_constructor: ");
2096 methodOop ctor = java_lang_Class::resolved_constructor(obj);
2097 ctor->print_value_on(st);
2098 klassOop array_klass = java_lang_Class::array_klass(obj);
2099 st->cr();
2100 st->print(BULLET"fake entry for array: ");
2101 array_klass->print_value_on(st);
2102 st->cr();
2103 }
2104 }
2106 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2107 st->print("a ");
2108 name()->print_value_on(st);
2109 obj->print_address_on(st);
2110 if (as_klassOop() == SystemDictionary::string_klass()
2111 && java_lang_String::value(obj) != NULL) {
2112 ResourceMark rm;
2113 int len = java_lang_String::length(obj);
2114 int plen = (len < 24 ? len : 12);
2115 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2116 st->print(" = \"%s\"", str);
2117 if (len > plen)
2118 st->print("...[%d]", len);
2119 } else if (as_klassOop() == SystemDictionary::class_klass()) {
2120 klassOop k = java_lang_Class::as_klassOop(obj);
2121 st->print(" = ");
2122 if (k != NULL) {
2123 k->print_value_on(st);
2124 } else {
2125 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2126 st->print("%s", tname ? tname : "type?");
2127 }
2128 } else if (java_lang_boxing_object::is_instance(obj)) {
2129 st->print(" = ");
2130 java_lang_boxing_object::print(obj, st);
2131 }
2132 }
2134 #endif // ndef PRODUCT
2136 const char* instanceKlass::internal_name() const {
2137 return external_name();
2138 }
2140 // Verification
2142 class VerifyFieldClosure: public OopClosure {
2143 protected:
2144 template <class T> void do_oop_work(T* p) {
2145 guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
2146 oop obj = oopDesc::load_decode_heap_oop(p);
2147 if (!obj->is_oop_or_null()) {
2148 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2149 Universe::print();
2150 guarantee(false, "boom");
2151 }
2152 }
2153 public:
2154 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2155 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2156 };
2158 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
2159 Klass::oop_verify_on(obj, st);
2160 VerifyFieldClosure blk;
2161 oop_oop_iterate(obj, &blk);
2162 }
2164 #ifndef PRODUCT
2166 void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) {
2167 // This verification code is disabled. JDK_Version::is_gte_jdk14x_version()
2168 // cannot be called since this function is called before the VM is
2169 // able to determine what JDK version is running with.
2170 // The check below always is false since 1.4.
2171 return;
2173 // This verification code temporarily disabled for the 1.4
2174 // reflection implementation since java.lang.Class now has
2175 // Java-level instance fields. Should rewrite this to handle this
2176 // case.
2177 if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) {
2178 // Verify that java.lang.Class instances have a fake oop field added.
2179 instanceKlass* ik = instanceKlass::cast(k);
2181 // Check that we have the right class
2182 static bool first_time = true;
2183 guarantee(k == SystemDictionary::class_klass() && first_time, "Invalid verify of maps");
2184 first_time = false;
2185 const int extra = java_lang_Class::number_of_fake_oop_fields;
2186 guarantee(ik->nonstatic_field_size() == extra, "just checking");
2187 guarantee(ik->nonstatic_oop_map_size() == 1, "just checking");
2188 guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking");
2190 // Check that the map is (2,extra)
2191 int offset = java_lang_Class::klass_offset;
2193 OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
2194 guarantee(map->offset() == offset && map->length() == extra, "just checking");
2195 }
2196 }
2198 #endif // ndef PRODUCT
2200 // JNIid class for jfieldIDs only
2201 // Note to reviewers:
2202 // These JNI functions are just moved over to column 1 and not changed
2203 // in the compressed oops workspace.
2204 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
2205 _holder = holder;
2206 _offset = offset;
2207 _next = next;
2208 debug_only(_is_static_field_id = false;)
2209 }
2212 JNIid* JNIid::find(int offset) {
2213 JNIid* current = this;
2214 while (current != NULL) {
2215 if (current->offset() == offset) return current;
2216 current = current->next();
2217 }
2218 return NULL;
2219 }
2221 void JNIid::oops_do(OopClosure* f) {
2222 for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
2223 f->do_oop(cur->holder_addr());
2224 }
2225 }
2227 void JNIid::deallocate(JNIid* current) {
2228 while (current != NULL) {
2229 JNIid* next = current->next();
2230 delete current;
2231 current = next;
2232 }
2233 }
2236 void JNIid::verify(klassOop holder) {
2237 int first_field_offset = instanceKlass::cast(holder)->offset_of_static_fields();
2238 int end_field_offset;
2239 end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
2241 JNIid* current = this;
2242 while (current != NULL) {
2243 guarantee(current->holder() == holder, "Invalid klass in JNIid");
2244 #ifdef ASSERT
2245 int o = current->offset();
2246 if (current->is_static_field_id()) {
2247 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
2248 }
2249 #endif
2250 current = current->next();
2251 }
2252 }
2255 #ifdef ASSERT
2256 void instanceKlass::set_init_state(ClassState state) {
2257 bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
2258 : (_init_state < state);
2259 assert(good_state || state == allocated, "illegal state transition");
2260 _init_state = state;
2261 }
2262 #endif
2265 // RedefineClasses() support for previous versions:
2267 // Add an information node that contains weak references to the
2268 // interesting parts of the previous version of the_class.
2269 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
2270 BitMap* emcp_methods, int emcp_method_count) {
2271 assert(Thread::current()->is_VM_thread(),
2272 "only VMThread can add previous versions");
2274 if (_previous_versions == NULL) {
2275 // This is the first previous version so make some space.
2276 // Start with 2 elements under the assumption that the class
2277 // won't be redefined much.
2278 _previous_versions = new (ResourceObj::C_HEAP)
2279 GrowableArray<PreviousVersionNode *>(2, true);
2280 }
2282 // RC_TRACE macro has an embedded ResourceMark
2283 RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
2284 ikh->external_name(), _previous_versions->length(), emcp_method_count));
2285 constantPoolHandle cp_h(ikh->constants());
2286 jobject cp_ref;
2287 if (cp_h->is_shared()) {
2288 // a shared ConstantPool requires a regular reference; a weak
2289 // reference would be collectible
2290 cp_ref = JNIHandles::make_global(cp_h);
2291 } else {
2292 cp_ref = JNIHandles::make_weak_global(cp_h);
2293 }
2294 PreviousVersionNode * pv_node = NULL;
2295 objArrayOop old_methods = ikh->methods();
2297 if (emcp_method_count == 0) {
2298 // non-shared ConstantPool gets a weak reference
2299 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL);
2300 RC_TRACE(0x00000400,
2301 ("add: all methods are obsolete; flushing any EMCP weak refs"));
2302 } else {
2303 int local_count = 0;
2304 GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
2305 GrowableArray<jweak>(emcp_method_count, true);
2306 for (int i = 0; i < old_methods->length(); i++) {
2307 if (emcp_methods->at(i)) {
2308 // this old method is EMCP so save a weak ref
2309 methodOop old_method = (methodOop) old_methods->obj_at(i);
2310 methodHandle old_method_h(old_method);
2311 jweak method_ref = JNIHandles::make_weak_global(old_method_h);
2312 method_refs->append(method_ref);
2313 if (++local_count >= emcp_method_count) {
2314 // no more EMCP methods so bail out now
2315 break;
2316 }
2317 }
2318 }
2319 // non-shared ConstantPool gets a weak reference
2320 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs);
2321 }
2323 _previous_versions->append(pv_node);
2325 // Using weak references allows the interesting parts of previous
2326 // classes to be GC'ed when they are no longer needed. Since the
2327 // caller is the VMThread and we are at a safepoint, this is a good
2328 // time to clear out unused weak references.
2330 RC_TRACE(0x00000400, ("add: previous version length=%d",
2331 _previous_versions->length()));
2333 // skip the last entry since we just added it
2334 for (int i = _previous_versions->length() - 2; i >= 0; i--) {
2335 // check the previous versions array for a GC'ed weak refs
2336 pv_node = _previous_versions->at(i);
2337 cp_ref = pv_node->prev_constant_pool();
2338 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2339 if (cp_ref == NULL) {
2340 delete pv_node;
2341 _previous_versions->remove_at(i);
2342 // Since we are traversing the array backwards, we don't have to
2343 // do anything special with the index.
2344 continue; // robustness
2345 }
2347 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2348 if (cp == NULL) {
2349 // this entry has been GC'ed so remove it
2350 delete pv_node;
2351 _previous_versions->remove_at(i);
2352 // Since we are traversing the array backwards, we don't have to
2353 // do anything special with the index.
2354 continue;
2355 } else {
2356 RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
2357 }
2359 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2360 if (method_refs != NULL) {
2361 RC_TRACE(0x00000400, ("add: previous methods length=%d",
2362 method_refs->length()));
2363 for (int j = method_refs->length() - 1; j >= 0; j--) {
2364 jweak method_ref = method_refs->at(j);
2365 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2366 if (method_ref == NULL) {
2367 method_refs->remove_at(j);
2368 // Since we are traversing the array backwards, we don't have to
2369 // do anything special with the index.
2370 continue; // robustness
2371 }
2373 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2374 if (method == NULL || emcp_method_count == 0) {
2375 // This method entry has been GC'ed or the current
2376 // RedefineClasses() call has made all methods obsolete
2377 // so remove it.
2378 JNIHandles::destroy_weak_global(method_ref);
2379 method_refs->remove_at(j);
2380 } else {
2381 // RC_TRACE macro has an embedded ResourceMark
2382 RC_TRACE(0x00000400,
2383 ("add: %s(%s): previous method @%d in version @%d is alive",
2384 method->name()->as_C_string(), method->signature()->as_C_string(),
2385 j, i));
2386 }
2387 }
2388 }
2389 }
2391 int obsolete_method_count = old_methods->length() - emcp_method_count;
2393 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
2394 _previous_versions->length() > 1) {
2395 // We have a mix of obsolete and EMCP methods. If there is more
2396 // than the previous version that we just added, then we have to
2397 // clear out any matching EMCP method entries the hard way.
2398 int local_count = 0;
2399 for (int i = 0; i < old_methods->length(); i++) {
2400 if (!emcp_methods->at(i)) {
2401 // only obsolete methods are interesting
2402 methodOop old_method = (methodOop) old_methods->obj_at(i);
2403 symbolOop m_name = old_method->name();
2404 symbolOop m_signature = old_method->signature();
2406 // skip the last entry since we just added it
2407 for (int j = _previous_versions->length() - 2; j >= 0; j--) {
2408 // check the previous versions array for a GC'ed weak refs
2409 pv_node = _previous_versions->at(j);
2410 cp_ref = pv_node->prev_constant_pool();
2411 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2412 if (cp_ref == NULL) {
2413 delete pv_node;
2414 _previous_versions->remove_at(j);
2415 // Since we are traversing the array backwards, we don't have to
2416 // do anything special with the index.
2417 continue; // robustness
2418 }
2420 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2421 if (cp == NULL) {
2422 // this entry has been GC'ed so remove it
2423 delete pv_node;
2424 _previous_versions->remove_at(j);
2425 // Since we are traversing the array backwards, we don't have to
2426 // do anything special with the index.
2427 continue;
2428 }
2430 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2431 if (method_refs == NULL) {
2432 // We have run into a PreviousVersion generation where
2433 // all methods were made obsolete during that generation's
2434 // RedefineClasses() operation. At the time of that
2435 // operation, all EMCP methods were flushed so we don't
2436 // have to go back any further.
2437 //
2438 // A NULL method_refs is different than an empty method_refs.
2439 // We cannot infer any optimizations about older generations
2440 // from an empty method_refs for the current generation.
2441 break;
2442 }
2444 for (int k = method_refs->length() - 1; k >= 0; k--) {
2445 jweak method_ref = method_refs->at(k);
2446 assert(method_ref != NULL,
2447 "weak method ref was unexpectedly cleared");
2448 if (method_ref == NULL) {
2449 method_refs->remove_at(k);
2450 // Since we are traversing the array backwards, we don't
2451 // have to do anything special with the index.
2452 continue; // robustness
2453 }
2455 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2456 if (method == NULL) {
2457 // this method entry has been GC'ed so skip it
2458 JNIHandles::destroy_weak_global(method_ref);
2459 method_refs->remove_at(k);
2460 continue;
2461 }
2463 if (method->name() == m_name &&
2464 method->signature() == m_signature) {
2465 // The current RedefineClasses() call has made all EMCP
2466 // versions of this method obsolete so mark it as obsolete
2467 // and remove the weak ref.
2468 RC_TRACE(0x00000400,
2469 ("add: %s(%s): flush obsolete method @%d in version @%d",
2470 m_name->as_C_string(), m_signature->as_C_string(), k, j));
2472 method->set_is_obsolete();
2473 JNIHandles::destroy_weak_global(method_ref);
2474 method_refs->remove_at(k);
2475 break;
2476 }
2477 }
2479 // The previous loop may not find a matching EMCP method, but
2480 // that doesn't mean that we can optimize and not go any
2481 // further back in the PreviousVersion generations. The EMCP
2482 // method for this generation could have already been GC'ed,
2483 // but there still may be an older EMCP method that has not
2484 // been GC'ed.
2485 }
2487 if (++local_count >= obsolete_method_count) {
2488 // no more obsolete methods so bail out now
2489 break;
2490 }
2491 }
2492 }
2493 }
2494 } // end add_previous_version()
2497 // Determine if instanceKlass has a previous version.
2498 bool instanceKlass::has_previous_version() const {
2499 if (_previous_versions == NULL) {
2500 // no previous versions array so answer is easy
2501 return false;
2502 }
2504 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2505 // Check the previous versions array for an info node that hasn't
2506 // been GC'ed
2507 PreviousVersionNode * pv_node = _previous_versions->at(i);
2509 jobject cp_ref = pv_node->prev_constant_pool();
2510 assert(cp_ref != NULL, "cp reference was unexpectedly cleared");
2511 if (cp_ref == NULL) {
2512 continue; // robustness
2513 }
2515 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2516 if (cp != NULL) {
2517 // we have at least one previous version
2518 return true;
2519 }
2521 // We don't have to check the method refs. If the constant pool has
2522 // been GC'ed then so have the methods.
2523 }
2525 // all of the underlying nodes' info has been GC'ed
2526 return false;
2527 } // end has_previous_version()
2529 methodOop instanceKlass::method_with_idnum(int idnum) {
2530 methodOop m = NULL;
2531 if (idnum < methods()->length()) {
2532 m = (methodOop) methods()->obj_at(idnum);
2533 }
2534 if (m == NULL || m->method_idnum() != idnum) {
2535 for (int index = 0; index < methods()->length(); ++index) {
2536 m = (methodOop) methods()->obj_at(index);
2537 if (m->method_idnum() == idnum) {
2538 return m;
2539 }
2540 }
2541 }
2542 return m;
2543 }
2546 // Set the annotation at 'idnum' to 'anno'.
2547 // We don't want to create or extend the array if 'anno' is NULL, since that is the
2548 // default value. However, if the array exists and is long enough, we must set NULL values.
2549 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
2550 objArrayOop md = *md_p;
2551 if (md != NULL && md->length() > idnum) {
2552 md->obj_at_put(idnum, anno);
2553 } else if (anno != NULL) {
2554 // create the array
2555 int length = MAX2(idnum+1, (int)_idnum_allocated_count);
2556 md = oopFactory::new_system_objArray(length, Thread::current());
2557 if (*md_p != NULL) {
2558 // copy the existing entries
2559 for (int index = 0; index < (*md_p)->length(); index++) {
2560 md->obj_at_put(index, (*md_p)->obj_at(index));
2561 }
2562 }
2563 set_annotations(md, md_p);
2564 md->obj_at_put(idnum, anno);
2565 } // if no array and idnum isn't included there is nothing to do
2566 }
2568 // Construct a PreviousVersionNode entry for the array hung off
2569 // the instanceKlass.
2570 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool,
2571 bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) {
2573 _prev_constant_pool = prev_constant_pool;
2574 _prev_cp_is_weak = prev_cp_is_weak;
2575 _prev_EMCP_methods = prev_EMCP_methods;
2576 }
2579 // Destroy a PreviousVersionNode
2580 PreviousVersionNode::~PreviousVersionNode() {
2581 if (_prev_constant_pool != NULL) {
2582 if (_prev_cp_is_weak) {
2583 JNIHandles::destroy_weak_global(_prev_constant_pool);
2584 } else {
2585 JNIHandles::destroy_global(_prev_constant_pool);
2586 }
2587 }
2589 if (_prev_EMCP_methods != NULL) {
2590 for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
2591 jweak method_ref = _prev_EMCP_methods->at(i);
2592 if (method_ref != NULL) {
2593 JNIHandles::destroy_weak_global(method_ref);
2594 }
2595 }
2596 delete _prev_EMCP_methods;
2597 }
2598 }
2601 // Construct a PreviousVersionInfo entry
2602 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
2603 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
2604 _prev_EMCP_method_handles = NULL;
2606 jobject cp_ref = pv_node->prev_constant_pool();
2607 assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared");
2608 if (cp_ref == NULL) {
2609 return; // robustness
2610 }
2612 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2613 if (cp == NULL) {
2614 // Weak reference has been GC'ed. Since the constant pool has been
2615 // GC'ed, the methods have also been GC'ed.
2616 return;
2617 }
2619 // make the constantPoolOop safe to return
2620 _prev_constant_pool_handle = constantPoolHandle(cp);
2622 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2623 if (method_refs == NULL) {
2624 // the instanceKlass did not have any EMCP methods
2625 return;
2626 }
2628 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
2630 int n_methods = method_refs->length();
2631 for (int i = 0; i < n_methods; i++) {
2632 jweak method_ref = method_refs->at(i);
2633 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2634 if (method_ref == NULL) {
2635 continue; // robustness
2636 }
2638 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2639 if (method == NULL) {
2640 // this entry has been GC'ed so skip it
2641 continue;
2642 }
2644 // make the methodOop safe to return
2645 _prev_EMCP_method_handles->append(methodHandle(method));
2646 }
2647 }
2650 // Destroy a PreviousVersionInfo
2651 PreviousVersionInfo::~PreviousVersionInfo() {
2652 // Since _prev_EMCP_method_handles is not C-heap allocated, we
2653 // don't have to delete it.
2654 }
2657 // Construct a helper for walking the previous versions array
2658 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
2659 _previous_versions = ik->previous_versions();
2660 _current_index = 0;
2661 // _hm needs no initialization
2662 _current_p = NULL;
2663 }
2666 // Destroy a PreviousVersionWalker
2667 PreviousVersionWalker::~PreviousVersionWalker() {
2668 // Delete the current info just in case the caller didn't walk to
2669 // the end of the previous versions list. No harm if _current_p is
2670 // already NULL.
2671 delete _current_p;
2673 // When _hm is destroyed, all the Handles returned in
2674 // PreviousVersionInfo objects will be destroyed.
2675 // Also, after this destructor is finished it will be
2676 // safe to delete the GrowableArray allocated in the
2677 // PreviousVersionInfo objects.
2678 }
2681 // Return the interesting information for the next previous version
2682 // of the klass. Returns NULL if there are no more previous versions.
2683 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
2684 if (_previous_versions == NULL) {
2685 // no previous versions so nothing to return
2686 return NULL;
2687 }
2689 delete _current_p; // cleanup the previous info for the caller
2690 _current_p = NULL; // reset to NULL so we don't delete same object twice
2692 int length = _previous_versions->length();
2694 while (_current_index < length) {
2695 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
2696 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
2697 PreviousVersionInfo(pv_node);
2699 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
2700 if (cp_h.is_null()) {
2701 delete pv_info;
2703 // The underlying node's info has been GC'ed so try the next one.
2704 // We don't have to check the methods. If the constant pool has
2705 // GC'ed then so have the methods.
2706 continue;
2707 }
2709 // Found a node with non GC'ed info so return it. The caller will
2710 // need to delete pv_info when they are done with it.
2711 _current_p = pv_info;
2712 return pv_info;
2713 }
2715 // all of the underlying nodes' info has been GC'ed
2716 return NULL;
2717 } // end next_previous_version()