Fri, 25 Jan 2013 15:06:18 -0500
6479360: PrintClassHistogram improvements
Summary: jcmd <pid> GC.class_stats (UnlockDiagnosticVMOptions)
Reviewed-by: coleenp, hseigel, sla, acorn
Contributed-by: ioi.lam@oracle.com
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 */
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 "utilities/stack.hpp"
41 #ifndef SERIALGC
42 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
43 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
44 #include "gc_implementation/parallelScavenge/psScavenge.hpp"
45 #endif
47 void Klass::set_name(Symbol* n) {
48 _name = n;
49 if (_name != NULL) _name->increment_refcount();
50 }
52 bool Klass::is_subclass_of(Klass* k) const {
53 // Run up the super chain and check
54 if (this == k) return true;
56 Klass* t = const_cast<Klass*>(this)->super();
58 while (t != NULL) {
59 if (t == k) return true;
60 t = t->super();
61 }
62 return false;
63 }
65 bool Klass::search_secondary_supers(Klass* k) const {
66 // Put some extra logic here out-of-line, before the search proper.
67 // This cuts down the size of the inline method.
69 // This is necessary, since I am never in my own secondary_super list.
70 if (this == k)
71 return true;
72 // Scan the array-of-objects for a match
73 int cnt = secondary_supers()->length();
74 for (int i = 0; i < cnt; i++) {
75 if (secondary_supers()->at(i) == k) {
76 ((Klass*)this)->set_secondary_super_cache(k);
77 return true;
78 }
79 }
80 return false;
81 }
83 // Return self, except for abstract classes with exactly 1
84 // implementor. Then return the 1 concrete implementation.
85 Klass *Klass::up_cast_abstract() {
86 Klass *r = this;
87 while( r->is_abstract() ) { // Receiver is abstract?
88 Klass *s = r->subklass(); // Check for exactly 1 subklass
89 if( !s || s->next_sibling() ) // Oops; wrong count; give up
90 return this; // Return 'this' as a no-progress flag
91 r = s; // Loop till find concrete class
92 }
93 return r; // Return the 1 concrete class
94 }
96 // Find LCA in class hierarchy
97 Klass *Klass::LCA( Klass *k2 ) {
98 Klass *k1 = this;
99 while( 1 ) {
100 if( k1->is_subtype_of(k2) ) return k2;
101 if( k2->is_subtype_of(k1) ) return k1;
102 k1 = k1->super();
103 k2 = k2->super();
104 }
105 }
108 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
109 ResourceMark rm(THREAD);
110 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
111 : vmSymbols::java_lang_InstantiationException(), external_name());
112 }
115 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
116 THROW(vmSymbols::java_lang_ArrayStoreException());
117 }
120 void Klass::initialize(TRAPS) {
121 ShouldNotReachHere();
122 }
124 bool Klass::compute_is_subtype_of(Klass* k) {
125 assert(k->is_klass(), "argument must be a class");
126 return is_subclass_of(k);
127 }
130 Method* Klass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
131 #ifdef ASSERT
132 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
133 " Likely error: reflection method does not correctly"
134 " wrap return value in a mirror object.");
135 #endif
136 ShouldNotReachHere();
137 return NULL;
138 }
140 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) {
141 return Metaspace::allocate(loader_data, word_size, /*read_only*/false,
142 Metaspace::ClassType, CHECK_NULL);
143 }
145 Klass::Klass() {
146 Klass* k = this;
148 { // Preinitialize supertype information.
149 // A later call to initialize_supers() may update these settings:
150 set_super(NULL);
151 for (juint i = 0; i < Klass::primary_super_limit(); i++) {
152 _primary_supers[i] = NULL;
153 }
154 set_secondary_supers(NULL);
155 _primary_supers[0] = k;
156 set_super_check_offset(in_bytes(primary_supers_offset()));
157 }
159 set_java_mirror(NULL);
160 set_modifier_flags(0);
161 set_layout_helper(Klass::_lh_neutral_value);
162 set_name(NULL);
163 AccessFlags af;
164 af.set_flags(0);
165 set_access_flags(af);
166 set_subklass(NULL);
167 set_next_sibling(NULL);
168 set_next_link(NULL);
169 set_alloc_count(0);
170 TRACE_SET_KLASS_TRACE_ID(this, 0);
172 set_prototype_header(markOopDesc::prototype());
173 set_biased_lock_revocation_count(0);
174 set_last_biased_lock_bulk_revocation_time(0);
176 // The klass doesn't have any references at this point.
177 clear_modified_oops();
178 clear_accumulated_modified_oops();
179 }
181 jint Klass::array_layout_helper(BasicType etype) {
182 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
183 // Note that T_ARRAY is not allowed here.
184 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
185 int esize = type2aelembytes(etype);
186 bool isobj = (etype == T_OBJECT);
187 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
188 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
190 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
191 assert(layout_helper_is_array(lh), "correct kind");
192 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
193 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
194 assert(layout_helper_header_size(lh) == hsize, "correct decode");
195 assert(layout_helper_element_type(lh) == etype, "correct decode");
196 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
198 return lh;
199 }
201 bool Klass::can_be_primary_super_slow() const {
202 if (super() == NULL)
203 return true;
204 else if (super()->super_depth() >= primary_super_limit()-1)
205 return false;
206 else
207 return true;
208 }
210 void Klass::initialize_supers(Klass* k, TRAPS) {
211 if (FastSuperclassLimit == 0) {
212 // None of the other machinery matters.
213 set_super(k);
214 return;
215 }
216 if (k == NULL) {
217 set_super(NULL);
218 _primary_supers[0] = this;
219 assert(super_depth() == 0, "Object must already be initialized properly");
220 } else if (k != super() || k == SystemDictionary::Object_klass()) {
221 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
222 "initialize this only once to a non-trivial value");
223 set_super(k);
224 Klass* sup = k;
225 int sup_depth = sup->super_depth();
226 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
227 if (!can_be_primary_super_slow())
228 my_depth = primary_super_limit();
229 for (juint i = 0; i < my_depth; i++) {
230 _primary_supers[i] = sup->_primary_supers[i];
231 }
232 Klass* *super_check_cell;
233 if (my_depth < primary_super_limit()) {
234 _primary_supers[my_depth] = this;
235 super_check_cell = &_primary_supers[my_depth];
236 } else {
237 // Overflow of the primary_supers array forces me to be secondary.
238 super_check_cell = &_secondary_super_cache;
239 }
240 set_super_check_offset((address)super_check_cell - (address) this);
242 #ifdef ASSERT
243 {
244 juint j = super_depth();
245 assert(j == my_depth, "computed accessor gets right answer");
246 Klass* t = this;
247 while (!t->can_be_primary_super()) {
248 t = t->super();
249 j = t->super_depth();
250 }
251 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
252 assert(primary_super_of_depth(j1) == NULL, "super list padding");
253 }
254 while (t != NULL) {
255 assert(primary_super_of_depth(j) == t, "super list initialization");
256 t = t->super();
257 --j;
258 }
259 assert(j == (juint)-1, "correct depth count");
260 }
261 #endif
262 }
264 if (secondary_supers() == NULL) {
265 KlassHandle this_kh (THREAD, this);
267 // Now compute the list of secondary supertypes.
268 // Secondaries can occasionally be on the super chain,
269 // if the inline "_primary_supers" array overflows.
270 int extras = 0;
271 Klass* p;
272 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
273 ++extras;
274 }
276 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
278 // Compute the "real" non-extra secondaries.
279 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
280 if (secondaries == NULL) {
281 // secondary_supers set by compute_secondary_supers
282 return;
283 }
285 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
287 for (p = this_kh->super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
288 int i; // Scan for overflow primaries being duplicates of 2nd'arys
290 // This happens frequently for very deeply nested arrays: the
291 // primary superclass chain overflows into the secondary. The
292 // secondary list contains the element_klass's secondaries with
293 // an extra array dimension added. If the element_klass's
294 // secondary list already contains some primary overflows, they
295 // (with the extra level of array-ness) will collide with the
296 // normal primary superclass overflows.
297 for( i = 0; i < secondaries->length(); i++ ) {
298 if( secondaries->at(i) == p )
299 break;
300 }
301 if( i < secondaries->length() )
302 continue; // It's a dup, don't put it in
303 primaries->push(p);
304 }
305 // Combine the two arrays into a metadata object to pack the array.
306 // The primaries are added in the reverse order, then the secondaries.
307 int new_length = primaries->length() + secondaries->length();
308 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
309 class_loader_data(), new_length, CHECK);
310 int fill_p = primaries->length();
311 for (int j = 0; j < fill_p; j++) {
312 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
313 }
314 for( int j = 0; j < secondaries->length(); j++ ) {
315 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
316 }
318 #ifdef ASSERT
319 // We must not copy any NULL placeholders left over from bootstrap.
320 for (int j = 0; j < s2->length(); j++) {
321 assert(s2->at(j) != NULL, "correct bootstrapping order");
322 }
323 #endif
325 this_kh->set_secondary_supers(s2);
326 }
327 }
329 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
330 assert(num_extra_slots == 0, "override for complex klasses");
331 set_secondary_supers(Universe::the_empty_klass_array());
332 return NULL;
333 }
336 Klass* Klass::subklass() const {
337 return _subklass == NULL ? NULL : _subklass;
338 }
340 InstanceKlass* Klass::superklass() const {
341 assert(super() == NULL || super()->oop_is_instance(), "must be instance klass");
342 return _super == NULL ? NULL : InstanceKlass::cast(_super);
343 }
345 Klass* Klass::next_sibling() const {
346 return _next_sibling == NULL ? NULL : _next_sibling;
347 }
349 void Klass::set_subklass(Klass* s) {
350 assert(s != this, "sanity check");
351 _subklass = s;
352 }
354 void Klass::set_next_sibling(Klass* s) {
355 assert(s != this, "sanity check");
356 _next_sibling = s;
357 }
359 void Klass::append_to_sibling_list() {
360 debug_only(verify();)
361 // add ourselves to superklass' subklass list
362 InstanceKlass* super = superklass();
363 if (super == NULL) return; // special case: class Object
364 assert((!super->is_interface() // interfaces cannot be supers
365 && (super->superklass() == NULL || !is_interface())),
366 "an interface can only be a subklass of Object");
367 Klass* prev_first_subklass = super->subklass_oop();
368 if (prev_first_subklass != NULL) {
369 // set our sibling to be the superklass' previous first subklass
370 set_next_sibling(prev_first_subklass);
371 }
372 // make ourselves the superklass' first subklass
373 super->set_subklass(this);
374 debug_only(verify();)
375 }
377 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
378 assert(is_metadata(), "p is not meta-data");
379 assert(ClassLoaderDataGraph::contains((address)this), "is in the metaspace");
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
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 }
395 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive) {
396 if (!ClassUnloading) {
397 return;
398 }
400 Klass* root = SystemDictionary::Object_klass();
401 Stack<Klass*, mtGC> stack;
403 stack.push(root);
404 while (!stack.is_empty()) {
405 Klass* current = stack.pop();
407 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
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 }
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 }
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 }
448 void Klass::klass_update_barrier_set(oop v) {
449 record_modified_oops();
450 }
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 }
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");
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 }
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");
478 klass_update_barrier_set_pre((void*)p, v);
479 OrderAccess::release_store_ptr(p, v);
480 klass_update_barrier_set(v);
481 }
483 void Klass::oops_do(OopClosure* cl) {
484 cl->do_oop(&_java_mirror);
485 }
487 void Klass::remove_unshareable_info() {
488 set_subklass(NULL);
489 set_next_sibling(NULL);
490 // Clear the java mirror
491 set_java_mirror(NULL);
492 set_next_link(NULL);
494 // Null out class_loader_data because we don't share that yet.
495 set_class_loader_data(NULL);
496 }
498 void Klass::restore_unshareable_info(TRAPS) {
499 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
500 // Restore class_loader_data to the null class loader data
501 set_class_loader_data(loader_data);
503 // Add to null class loader list first before creating the mirror
504 // (same order as class file parsing)
505 loader_data->add_class(this);
507 // Recreate the class mirror
508 java_lang_Class::create_mirror(this, CHECK);
509 }
511 Klass* Klass::array_klass_or_null(int rank) {
512 EXCEPTION_MARK;
513 // No exception can be thrown by array_klass_impl when called with or_null == true.
514 // (In anycase, the execption mark will fail if it do so)
515 return array_klass_impl(true, rank, THREAD);
516 }
519 Klass* Klass::array_klass_or_null() {
520 EXCEPTION_MARK;
521 // No exception can be thrown by array_klass_impl when called with or_null == true.
522 // (In anycase, the execption mark will fail if it do so)
523 return array_klass_impl(true, THREAD);
524 }
527 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
528 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
529 return NULL;
530 }
533 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
534 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
535 return NULL;
536 }
539 void Klass::with_array_klasses_do(void f(Klass* k)) {
540 f(this);
541 }
544 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
546 const char* Klass::external_name() const {
547 if (oop_is_instance()) {
548 InstanceKlass* ik = (InstanceKlass*) this;
549 if (ik->is_anonymous()) {
550 assert(EnableInvokeDynamic, "");
551 intptr_t hash = 0;
552 if (ik->java_mirror() != NULL) {
553 // java_mirror might not be created yet, return 0 as hash.
554 hash = ik->java_mirror()->identity_hash();
555 }
556 char hash_buf[40];
557 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
558 size_t hash_len = strlen(hash_buf);
560 size_t result_len = name()->utf8_length();
561 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
562 name()->as_klass_external_name(result, (int) result_len + 1);
563 assert(strlen(result) == result_len, "");
564 strcpy(result + result_len, hash_buf);
565 assert(strlen(result) == result_len + hash_len, "");
566 return result;
567 }
568 }
569 if (name() == NULL) return "<unknown>";
570 return name()->as_klass_external_name();
571 }
574 const char* Klass::signature_name() const {
575 if (name() == NULL) return "<unknown>";
576 return name()->as_C_string();
577 }
579 // Unless overridden, modifier_flags is 0.
580 jint Klass::compute_modifier_flags(TRAPS) const {
581 return 0;
582 }
584 int Klass::atomic_incr_biased_lock_revocation_count() {
585 return (int) Atomic::add(1, &_biased_lock_revocation_count);
586 }
588 // Unless overridden, jvmti_class_status has no flags set.
589 jint Klass::jvmti_class_status() const {
590 return 0;
591 }
594 // Printing
596 void Klass::print_on(outputStream* st) const {
597 ResourceMark rm;
598 // print title
599 st->print("%s", internal_name());
600 print_address_on(st);
601 st->cr();
602 }
604 void Klass::oop_print_on(oop obj, outputStream* st) {
605 ResourceMark rm;
606 // print title
607 st->print_cr("%s ", internal_name());
608 obj->print_address_on(st);
610 if (WizardMode) {
611 // print header
612 obj->mark()->print_on(st);
613 }
615 // print class
616 st->print(" - klass: ");
617 obj->klass()->print_value_on(st);
618 st->cr();
619 }
621 void Klass::oop_print_value_on(oop obj, outputStream* st) {
622 // print title
623 ResourceMark rm; // Cannot print in debug mode without this
624 st->print("%s", internal_name());
625 obj->print_address_on(st);
626 }
628 #if INCLUDE_SERVICES
629 // Size Statistics
630 void Klass::collect_statistics(KlassSizeStats *sz) const {
631 sz->_klass_bytes = sz->count(this);
632 sz->_mirror_bytes = sz->count(java_mirror());
633 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
635 sz->_ro_bytes += sz->_secondary_supers_bytes;
636 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
637 }
638 #endif // INCLUDE_SERVICES
640 // Verification
642 void Klass::verify_on(outputStream* st) {
643 guarantee(!Universe::heap()->is_in_reserved(this), "Shouldn't be");
644 guarantee(this->is_metadata(), "should be in metaspace");
646 assert(ClassLoaderDataGraph::contains((address)this), "Should be");
648 guarantee(this->is_klass(),"should be klass");
650 if (super() != NULL) {
651 guarantee(super()->is_metadata(), "should be in metaspace");
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_metadata(), "should be in metaspace");
657 guarantee(ko->is_klass(), "should be klass");
658 }
659 for ( uint i = 0; i < primary_super_limit(); i++ ) {
660 Klass* ko = _primary_supers[i];
661 if (ko != NULL) {
662 guarantee(ko->is_metadata(), "should be in metaspace");
663 guarantee(ko->is_klass(), "should be klass");
664 }
665 }
667 if (java_mirror() != NULL) {
668 guarantee(java_mirror()->is_oop(), "should be instance");
669 }
670 }
672 void Klass::oop_verify_on(oop obj, outputStream* st) {
673 guarantee(obj->is_oop(), "should be oop");
674 guarantee(obj->klass()->is_metadata(), "should not be in Java heap");
675 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
676 }
678 #ifndef PRODUCT
680 void Klass::verify_vtable_index(int i) {
681 if (oop_is_instance()) {
682 assert(i>=0 && i<((InstanceKlass*)this)->vtable_length()/vtableEntry::size(), "index out of bounds");
683 } else {
684 assert(oop_is_array(), "Must be");
685 assert(i>=0 && i<((ArrayKlass*)this)->vtable_length()/vtableEntry::size(), "index out of bounds");
686 }
687 }
689 #endif