1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/dictionary.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "gc_implementation/shared/markSweep.inline.hpp"
31 #include "gc_interface/collectedHeap.inline.hpp"
32 #include "memory/heapInspection.hpp"
33 #include "memory/metadataFactory.hpp"
34 #include "memory/oopFactory.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "oops/instanceKlass.hpp"
37 #include "oops/klass.inline.hpp"
38 #include "oops/oop.inline2.hpp"
39 #include "runtime/atomic.hpp"
40 #include "trace/traceMacros.hpp"
41 #include "utilities/stack.hpp"
42 #include "utilities/macros.hpp"
43 #if INCLUDE_ALL_GCS
44 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
45 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
46 #include "gc_implementation/parallelScavenge/psScavenge.hpp"
47 #endif // INCLUDE_ALL_GCS
48
49 void Klass::set_name(Symbol* n) {
50 _name = n;
51 if (_name != NULL) _name->increment_refcount();
52 }
53
54 bool Klass::is_subclass_of(const Klass* k) const {
55 // Run up the super chain and check
56 if (this == k) return true;
57
58 Klass* t = const_cast<Klass*>(this)->super();
59
60 while (t != NULL) {
61 if (t == k) return true;
62 t = t->super();
63 }
64 return false;
65 }
66
67 bool Klass::search_secondary_supers(Klass* k) const {
68 // Put some extra logic here out-of-line, before the search proper.
69 // This cuts down the size of the inline method.
70
71 // This is necessary, since I am never in my own secondary_super list.
72 if (this == k)
73 return true;
74 // Scan the array-of-objects for a match
75 int cnt = secondary_supers()->length();
76 for (int i = 0; i < cnt; i++) {
77 if (secondary_supers()->at(i) == k) {
78 ((Klass*)this)->set_secondary_super_cache(k);
79 return true;
80 }
81 }
82 return false;
83 }
84
85 // Return self, except for abstract classes with exactly 1
86 // implementor. Then return the 1 concrete implementation.
87 Klass *Klass::up_cast_abstract() {
88 Klass *r = this;
89 while( r->is_abstract() ) { // Receiver is abstract?
90 Klass *s = r->subklass(); // Check for exactly 1 subklass
91 if( !s || s->next_sibling() ) // Oops; wrong count; give up
92 return this; // Return 'this' as a no-progress flag
93 r = s; // Loop till find concrete class
94 }
95 return r; // Return the 1 concrete class
96 }
97
98 // Find LCA in class hierarchy
99 Klass *Klass::LCA( Klass *k2 ) {
100 Klass *k1 = this;
101 while( 1 ) {
102 if( k1->is_subtype_of(k2) ) return k2;
103 if( k2->is_subtype_of(k1) ) return k1;
104 k1 = k1->super();
105 k2 = k2->super();
106 }
107 }
108
109
110 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
111 ResourceMark rm(THREAD);
112 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
113 : vmSymbols::java_lang_InstantiationException(), external_name());
114 }
115
116
117 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
118 THROW(vmSymbols::java_lang_ArrayStoreException());
119 }
120
121
122 void Klass::initialize(TRAPS) {
123 ShouldNotReachHere();
124 }
125
126 bool Klass::compute_is_subtype_of(Klass* k) {
127 assert(k->is_klass(), "argument must be a class");
128 return is_subclass_of(k);
129 }
130
131
132 Method* Klass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
133 #ifdef ASSERT
134 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
135 " Likely error: reflection method does not correctly"
136 " wrap return value in a mirror object.");
137 #endif
138 ShouldNotReachHere();
139 return NULL;
140 }
141
142 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) {
143 return Metaspace::allocate(loader_data, word_size, /*read_only*/false,
144 MetaspaceObj::ClassType, CHECK_NULL);
145 }
146
147 Klass::Klass() {
148 Klass* k = this;
149
150 // Preinitialize supertype information.
151 // A later call to initialize_supers() may update these settings:
152 set_super(NULL);
153 for (juint i = 0; i < Klass::primary_super_limit(); i++) {
154 _primary_supers[i] = NULL;
155 }
156 set_secondary_supers(NULL);
157 set_secondary_super_cache(NULL);
158 _primary_supers[0] = k;
159 set_super_check_offset(in_bytes(primary_supers_offset()));
160
161 set_java_mirror(NULL);
162 set_modifier_flags(0);
163 set_layout_helper(Klass::_lh_neutral_value);
164 set_name(NULL);
165 AccessFlags af;
166 af.set_flags(0);
167 set_access_flags(af);
168 set_subklass(NULL);
169 set_next_sibling(NULL);
170 set_next_link(NULL);
171 TRACE_INIT_ID(this);
172
173 set_prototype_header(markOopDesc::prototype());
174 set_biased_lock_revocation_count(0);
175 set_last_biased_lock_bulk_revocation_time(0);
176
177 // The klass doesn't have any references at this point.
178 clear_modified_oops();
179 clear_accumulated_modified_oops();
180 }
181
182 jint Klass::array_layout_helper(BasicType etype) {
183 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
184 // Note that T_ARRAY is not allowed here.
185 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
186 int esize = type2aelembytes(etype);
187 bool isobj = (etype == T_OBJECT);
188 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
189 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
190
191 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
192 assert(layout_helper_is_array(lh), "correct kind");
193 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
194 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
195 assert(layout_helper_header_size(lh) == hsize, "correct decode");
196 assert(layout_helper_element_type(lh) == etype, "correct decode");
197 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
198
199 return lh;
200 }
201
202 bool Klass::can_be_primary_super_slow() const {
203 if (super() == NULL)
204 return true;
205 else if (super()->super_depth() >= primary_super_limit()-1)
206 return false;
207 else
208 return true;
209 }
210
211 void Klass::initialize_supers(Klass* k, TRAPS) {
212 if (FastSuperclassLimit == 0) {
213 // None of the other machinery matters.
214 set_super(k);
215 return;
216 }
217 if (k == NULL) {
218 set_super(NULL);
219 _primary_supers[0] = this;
220 assert(super_depth() == 0, "Object must already be initialized properly");
221 } else if (k != super() || k == SystemDictionary::Object_klass()) {
222 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
223 "initialize this only once to a non-trivial value");
224 set_super(k);
225 Klass* sup = k;
226 int sup_depth = sup->super_depth();
227 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
228 if (!can_be_primary_super_slow())
229 my_depth = primary_super_limit();
230 for (juint i = 0; i < my_depth; i++) {
231 _primary_supers[i] = sup->_primary_supers[i];
232 }
233 Klass* *super_check_cell;
234 if (my_depth < primary_super_limit()) {
235 _primary_supers[my_depth] = this;
236 super_check_cell = &_primary_supers[my_depth];
237 } else {
238 // Overflow of the primary_supers array forces me to be secondary.
239 super_check_cell = &_secondary_super_cache;
240 }
241 set_super_check_offset((address)super_check_cell - (address) this);
242
243 #ifdef ASSERT
244 {
245 juint j = super_depth();
246 assert(j == my_depth, "computed accessor gets right answer");
247 Klass* t = this;
248 while (!t->can_be_primary_super()) {
249 t = t->super();
250 j = t->super_depth();
251 }
252 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
253 assert(primary_super_of_depth(j1) == NULL, "super list padding");
254 }
255 while (t != NULL) {
256 assert(primary_super_of_depth(j) == t, "super list initialization");
257 t = t->super();
258 --j;
259 }
260 assert(j == (juint)-1, "correct depth count");
261 }
262 #endif
263 }
264
265 if (secondary_supers() == NULL) {
266 KlassHandle this_kh (THREAD, this);
267
268 // Now compute the list of secondary supertypes.
269 // Secondaries can occasionally be on the super chain,
270 // if the inline "_primary_supers" array overflows.
271 int extras = 0;
272 Klass* p;
273 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
274 ++extras;
275 }
276
277 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
278
279 // Compute the "real" non-extra secondaries.
280 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
281 if (secondaries == NULL) {
282 // secondary_supers set by compute_secondary_supers
283 return;
284 }
285
286 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
287
288 for (p = this_kh->super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
289 int i; // Scan for overflow primaries being duplicates of 2nd'arys
290
291 // This happens frequently for very deeply nested arrays: the
292 // primary superclass chain overflows into the secondary. The
293 // secondary list contains the element_klass's secondaries with
294 // an extra array dimension added. If the element_klass's
295 // secondary list already contains some primary overflows, they
296 // (with the extra level of array-ness) will collide with the
297 // normal primary superclass overflows.
298 for( i = 0; i < secondaries->length(); i++ ) {
299 if( secondaries->at(i) == p )
300 break;
301 }
302 if( i < secondaries->length() )
303 continue; // It's a dup, don't put it in
304 primaries->push(p);
305 }
306 // Combine the two arrays into a metadata object to pack the array.
307 // The primaries are added in the reverse order, then the secondaries.
308 int new_length = primaries->length() + secondaries->length();
309 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
310 class_loader_data(), new_length, CHECK);
311 int fill_p = primaries->length();
312 for (int j = 0; j < fill_p; j++) {
313 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
314 }
315 for( int j = 0; j < secondaries->length(); j++ ) {
316 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
317 }
318
319 #ifdef ASSERT
320 // We must not copy any NULL placeholders left over from bootstrap.
321 for (int j = 0; j < s2->length(); j++) {
322 assert(s2->at(j) != NULL, "correct bootstrapping order");
323 }
324 #endif
325
326 this_kh->set_secondary_supers(s2);
327 }
328 }
329
330 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
331 assert(num_extra_slots == 0, "override for complex klasses");
332 set_secondary_supers(Universe::the_empty_klass_array());
333 return NULL;
334 }
335
336
337 Klass* Klass::subklass() const {
338 return _subklass == NULL ? NULL : _subklass;
339 }
340
341 InstanceKlass* Klass::superklass() const {
342 assert(super() == NULL || super()->oop_is_instance(), "must be instance klass");
343 return _super == NULL ? NULL : InstanceKlass::cast(_super);
344 }
345
346 Klass* Klass::next_sibling() const {
347 return _next_sibling == NULL ? NULL : _next_sibling;
348 }
349
350 void Klass::set_subklass(Klass* s) {
351 assert(s != this, "sanity check");
352 _subklass = s;
353 }
354
355 void Klass::set_next_sibling(Klass* s) {
356 assert(s != this, "sanity check");
357 _next_sibling = s;
358 }
359
360 void Klass::append_to_sibling_list() {
361 debug_only(verify();)
362 // add ourselves to superklass' subklass list
363 InstanceKlass* super = superklass();
364 if (super == NULL) return; // special case: class Object
365 assert((!super->is_interface() // interfaces cannot be supers
366 && (super->superklass() == NULL || !is_interface())),
367 "an interface can only be a subklass of Object");
368 Klass* prev_first_subklass = super->subklass_oop();
369 if (prev_first_subklass != NULL) {
370 // set our sibling to be the superklass' previous first subklass
371 set_next_sibling(prev_first_subklass);
372 }
373 // make ourselves the superklass' first subklass
374 super->set_subklass(this);
375 debug_only(verify();)
376 }
377
378 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
379 assert(ClassLoaderDataGraph::contains((address)this), "is in the metaspace");
380
381 #ifdef ASSERT
382 // The class is alive iff the class loader is alive.
383 oop loader = class_loader();
384 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
385 #endif // ASSERT
386
387 // The class is alive if it's mirror is alive (which should be marked if the
388 // loader is alive) unless it's an anoymous class.
389 bool mirror_alive = is_alive->do_object_b(java_mirror());
390 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
391 " but not the other way around with anonymous classes");
392 return mirror_alive;
393 }
394
395 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive) {
396 if (!ClassUnloading) {
397 return;
398 }
399
400 Klass* root = SystemDictionary::Object_klass();
401 Stack<Klass*, mtGC> stack;
402
403 stack.push(root);
404 while (!stack.is_empty()) {
405 Klass* current = stack.pop();
406
407 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
408
409 // Find and set the first alive subklass
410 Klass* sub = current->subklass_oop();
411 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
412 #ifndef PRODUCT
413 if (TraceClassUnloading && WizardMode) {
414 ResourceMark rm;
415 tty->print_cr("[Unlinking class (subclass) %s]", sub->external_name());
416 }
417 #endif
418 sub = sub->next_sibling_oop();
419 }
420 current->set_subklass(sub);
421 if (sub != NULL) {
422 stack.push(sub);
423 }
424
425 // Find and set the first alive sibling
426 Klass* sibling = current->next_sibling_oop();
427 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
428 if (TraceClassUnloading && WizardMode) {
429 ResourceMark rm;
430 tty->print_cr("[Unlinking class (sibling) %s]", sibling->external_name());
431 }
432 sibling = sibling->next_sibling_oop();
433 }
434 current->set_next_sibling(sibling);
435 if (sibling != NULL) {
436 stack.push(sibling);
437 }
438
439 // Clean the implementors list and method data.
440 if (current->oop_is_instance()) {
441 InstanceKlass* ik = InstanceKlass::cast(current);
442 ik->clean_implementors_list(is_alive);
443 ik->clean_method_data(is_alive);
444 }
445 }
446 }
447
448 void Klass::klass_update_barrier_set(oop v) {
449 record_modified_oops();
450 }
451
452 void Klass::klass_update_barrier_set_pre(void* p, oop v) {
453 // This barrier used by G1, where it's used remember the old oop values,
454 // so that we don't forget any objects that were live at the snapshot at
455 // the beginning. This function is only used when we write oops into
456 // Klasses. Since the Klasses are used as roots in G1, we don't have to
457 // do anything here.
458 }
459
460 void Klass::klass_oop_store(oop* p, oop v) {
461 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
462 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
463
464 // do the store
465 if (always_do_update_barrier) {
466 klass_oop_store((volatile oop*)p, v);
467 } else {
468 klass_update_barrier_set_pre((void*)p, v);
469 *p = v;
470 klass_update_barrier_set(v);
471 }
472 }
473
474 void Klass::klass_oop_store(volatile oop* p, oop v) {
475 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
476 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
477
478 klass_update_barrier_set_pre((void*)p, v);
479 OrderAccess::release_store_ptr(p, v);
480 klass_update_barrier_set(v);
481 }
482
483 void Klass::oops_do(OopClosure* cl) {
484 cl->do_oop(&_java_mirror);
485 }
486
487 void Klass::remove_unshareable_info() {
488 if (!DumpSharedSpaces) {
489 // Clean up after OOM during class loading
490 if (class_loader_data() != NULL) {
491 class_loader_data()->remove_class(this);
492 }
493 }
494 set_subklass(NULL);
495 set_next_sibling(NULL);
496 // Clear the java mirror
497 set_java_mirror(NULL);
498 set_next_link(NULL);
499
500 // Null out class_loader_data because we don't share that yet.
501 set_class_loader_data(NULL);
502 }
503
504 void Klass::restore_unshareable_info(TRAPS) {
505 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
506 // Restore class_loader_data to the null class loader data
507 set_class_loader_data(loader_data);
508
509 // Add to null class loader list first before creating the mirror
510 // (same order as class file parsing)
511 loader_data->add_class(this);
512
513 // Recreate the class mirror. The protection_domain is always null for
514 // boot loader, for now.
515 java_lang_Class::create_mirror(this, Handle(NULL), CHECK);
516 }
517
518 Klass* Klass::array_klass_or_null(int rank) {
519 EXCEPTION_MARK;
520 // No exception can be thrown by array_klass_impl when called with or_null == true.
521 // (In anycase, the execption mark will fail if it do so)
522 return array_klass_impl(true, rank, THREAD);
523 }
524
525
526 Klass* Klass::array_klass_or_null() {
527 EXCEPTION_MARK;
528 // No exception can be thrown by array_klass_impl when called with or_null == true.
529 // (In anycase, the execption mark will fail if it do so)
530 return array_klass_impl(true, THREAD);
531 }
532
533
534 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
535 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
536 return NULL;
537 }
538
539
540 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
541 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
542 return NULL;
543 }
544
545 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
546
547 const char* Klass::external_name() const {
548 if (oop_is_instance()) {
549 InstanceKlass* ik = (InstanceKlass*) this;
550 if (ik->is_anonymous()) {
551 assert(EnableInvokeDynamic, "");
552 intptr_t hash = 0;
553 if (ik->java_mirror() != NULL) {
554 // java_mirror might not be created yet, return 0 as hash.
555 hash = ik->java_mirror()->identity_hash();
556 }
557 char hash_buf[40];
558 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
559 size_t hash_len = strlen(hash_buf);
560
561 size_t result_len = name()->utf8_length();
562 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
563 name()->as_klass_external_name(result, (int) result_len + 1);
564 assert(strlen(result) == result_len, "");
565 strcpy(result + result_len, hash_buf);
566 assert(strlen(result) == result_len + hash_len, "");
567 return result;
568 }
569 }
570 if (name() == NULL) return "<unknown>";
571 return name()->as_klass_external_name();
572 }
573
574
575 const char* Klass::signature_name() const {
576 if (name() == NULL) return "<unknown>";
577 return name()->as_C_string();
578 }
579
580 // Unless overridden, modifier_flags is 0.
581 jint Klass::compute_modifier_flags(TRAPS) const {
582 return 0;
583 }
584
585 int Klass::atomic_incr_biased_lock_revocation_count() {
586 return (int) Atomic::add(1, &_biased_lock_revocation_count);
587 }
588
589 // Unless overridden, jvmti_class_status has no flags set.
590 jint Klass::jvmti_class_status() const {
591 return 0;
592 }
593
594
595 // Printing
596
597 void Klass::print_on(outputStream* st) const {
598 ResourceMark rm;
599 // print title
600 st->print("%s", internal_name());
601 print_address_on(st);
602 st->cr();
603 }
604
605 void Klass::oop_print_on(oop obj, outputStream* st) {
606 ResourceMark rm;
607 // print title
608 st->print_cr("%s ", internal_name());
609 obj->print_address_on(st);
610
611 if (WizardMode) {
612 // print header
613 obj->mark()->print_on(st);
614 }
615
616 // print class
617 st->print(" - klass: ");
618 obj->klass()->print_value_on(st);
619 st->cr();
620 }
621
622 void Klass::oop_print_value_on(oop obj, outputStream* st) {
623 // print title
624 ResourceMark rm; // Cannot print in debug mode without this
625 st->print("%s", internal_name());
626 obj->print_address_on(st);
627 }
628
629 #if INCLUDE_SERVICES
630 // Size Statistics
631 void Klass::collect_statistics(KlassSizeStats *sz) const {
632 sz->_klass_bytes = sz->count(this);
633 sz->_mirror_bytes = sz->count(java_mirror());
634 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
635
636 sz->_ro_bytes += sz->_secondary_supers_bytes;
637 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
638 }
639 #endif // INCLUDE_SERVICES
640
641 // Verification
642
643 void Klass::verify_on(outputStream* st, bool check_dictionary) {
644
645 // This can be expensive, but it is worth checking that this klass is actually
646 // in the CLD graph but not in production.
647 assert(ClassLoaderDataGraph::contains((address)this), "Should be");
648
649 guarantee(this->is_klass(),"should be klass");
650
651 if (super() != NULL) {
652 guarantee(super()->is_klass(), "should be klass");
653 }
654 if (secondary_super_cache() != NULL) {
655 Klass* ko = secondary_super_cache();
656 guarantee(ko->is_klass(), "should be klass");
657 }
658 for ( uint i = 0; i < primary_super_limit(); i++ ) {
659 Klass* ko = _primary_supers[i];
660 if (ko != NULL) {
661 guarantee(ko->is_klass(), "should be klass");
662 }
663 }
664
665 if (java_mirror() != NULL) {
666 guarantee(java_mirror()->is_oop(), "should be instance");
667 }
668 }
669
670 void Klass::oop_verify_on(oop obj, outputStream* st) {
671 guarantee(obj->is_oop(), "should be oop");
672 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
673 }
674
675 #ifndef PRODUCT
676
677 bool Klass::verify_vtable_index(int i) {
678 if (oop_is_instance()) {
679 int limit = ((InstanceKlass*)this)->vtable_length()/vtableEntry::size();
680 assert(i >= 0 && i < limit, err_msg("index %d out of bounds %d", i, limit));
681 } else {
682 assert(oop_is_array(), "Must be");
683 int limit = ((ArrayKlass*)this)->vtable_length()/vtableEntry::size();
684 assert(i >= 0 && i < limit, err_msg("index %d out of bounds %d", i, limit));
685 }
686 return true;
687 }
688
689 bool Klass::verify_itable_index(int i) {
690 assert(oop_is_instance(), "");
691 int method_count = klassItable::method_count_for_interface(this);
692 assert(i >= 0 && i < method_count, "index out of bounds");
693 return true;
694 }
695
696 #endif