1 /*
2 * Copyright (c) 1997, 2017, 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/dictionary.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "logging/log.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.inline.hpp"
39 #include "runtime/atomic.hpp"
40 #include "runtime/orderAccess.inline.hpp"
41 #include "trace/traceMacros.hpp"
42 #include "utilities/macros.hpp"
43 #include "utilities/stack.inline.hpp"
44 #if INCLUDE_ALL_GCS
45 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
46 #endif // INCLUDE_ALL_GCS
47
48 bool Klass::is_cloneable() const {
49 return _access_flags.is_cloneable_fast() ||
50 is_subtype_of(SystemDictionary::Cloneable_klass());
51 }
52
53 void Klass::set_is_cloneable() {
54 if (name() != vmSymbols::java_lang_invoke_MemberName()) {
55 _access_flags.set_is_cloneable_fast();
56 } else {
57 assert(is_final(), "no subclasses allowed");
58 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
59 }
60 }
61
62 void Klass::set_name(Symbol* n) {
63 _name = n;
64 if (_name != NULL) _name->increment_refcount();
65 }
66
67 bool Klass::is_subclass_of(const Klass* k) const {
68 // Run up the super chain and check
69 if (this == k) return true;
70
71 Klass* t = const_cast<Klass*>(this)->super();
72
73 while (t != NULL) {
74 if (t == k) return true;
75 t = t->super();
76 }
77 return false;
78 }
79
80 bool Klass::search_secondary_supers(Klass* k) const {
81 // Put some extra logic here out-of-line, before the search proper.
82 // This cuts down the size of the inline method.
83
84 // This is necessary, since I am never in my own secondary_super list.
85 if (this == k)
86 return true;
87 // Scan the array-of-objects for a match
88 int cnt = secondary_supers()->length();
89 for (int i = 0; i < cnt; i++) {
90 if (secondary_supers()->at(i) == k) {
91 ((Klass*)this)->set_secondary_super_cache(k);
92 return true;
93 }
94 }
95 return false;
96 }
97
98 // Return self, except for abstract classes with exactly 1
99 // implementor. Then return the 1 concrete implementation.
100 Klass *Klass::up_cast_abstract() {
101 Klass *r = this;
102 while( r->is_abstract() ) { // Receiver is abstract?
103 Klass *s = r->subklass(); // Check for exactly 1 subklass
104 if( !s || s->next_sibling() ) // Oops; wrong count; give up
105 return this; // Return 'this' as a no-progress flag
106 r = s; // Loop till find concrete class
107 }
108 return r; // Return the 1 concrete class
109 }
110
111 // Find LCA in class hierarchy
112 Klass *Klass::LCA( Klass *k2 ) {
113 Klass *k1 = this;
114 while( 1 ) {
115 if( k1->is_subtype_of(k2) ) return k2;
116 if( k2->is_subtype_of(k1) ) return k1;
117 k1 = k1->super();
118 k2 = k2->super();
119 }
120 }
121
122
123 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
124 ResourceMark rm(THREAD);
125 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
126 : vmSymbols::java_lang_InstantiationException(), external_name());
127 }
128
129
130 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
131 THROW(vmSymbols::java_lang_ArrayStoreException());
132 }
133
134
135 void Klass::initialize(TRAPS) {
136 ShouldNotReachHere();
137 }
138
139 bool Klass::compute_is_subtype_of(Klass* k) {
140 assert(k->is_klass(), "argument must be a class");
141 return is_subclass_of(k);
142 }
143
144 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
145 #ifdef ASSERT
146 tty->print_cr("Error: find_field called on a klass oop."
147 " Likely error: reflection method does not correctly"
148 " wrap return value in a mirror object.");
149 #endif
150 ShouldNotReachHere();
151 return NULL;
152 }
153
154 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const {
155 #ifdef ASSERT
156 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
157 " Likely error: reflection method does not correctly"
158 " wrap return value in a mirror object.");
159 #endif
160 ShouldNotReachHere();
161 return NULL;
162 }
163
164 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
165 return Metaspace::allocate(loader_data, word_size, /*read_only*/false,
166 MetaspaceObj::ClassType, THREAD);
167 }
168
169 // "Normal" instantiation is preceeded by a MetaspaceObj allocation
170 // which zeros out memory - calloc equivalent.
171 // The constructor is also used from CppVtableCloner,
172 // which doesn't zero out the memory before calling the constructor.
173 // Need to set the _java_mirror field explicitly to not hit an assert that the field
174 // should be NULL before setting it.
175 Klass::Klass() : _prototype_header(markOopDesc::prototype()),
176 _shared_class_path_index(-1),
177 _java_mirror(NULL) {
178
179 _primary_supers[0] = this;
180 set_super_check_offset(in_bytes(primary_supers_offset()));
181 }
182
183 jint Klass::array_layout_helper(BasicType etype) {
184 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
185 // Note that T_ARRAY is not allowed here.
186 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
187 int esize = type2aelembytes(etype);
188 bool isobj = (etype == T_OBJECT);
189 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
190 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
191
192 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
193 assert(layout_helper_is_array(lh), "correct kind");
194 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
195 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
196 assert(layout_helper_header_size(lh) == hsize, "correct decode");
197 assert(layout_helper_element_type(lh) == etype, "correct decode");
198 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
199
200 return lh;
201 }
202
203 bool Klass::can_be_primary_super_slow() const {
204 if (super() == NULL)
205 return true;
206 else if (super()->super_depth() >= primary_super_limit()-1)
207 return false;
208 else
209 return true;
210 }
211
212 void Klass::initialize_supers(Klass* k, TRAPS) {
213 if (FastSuperclassLimit == 0) {
214 // None of the other machinery matters.
215 set_super(k);
216 return;
217 }
218 if (k == NULL) {
219 set_super(NULL);
220 _primary_supers[0] = this;
221 assert(super_depth() == 0, "Object must already be initialized properly");
222 } else if (k != super() || k == SystemDictionary::Object_klass()) {
223 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
224 "initialize this only once to a non-trivial value");
225 set_super(k);
226 Klass* sup = k;
227 int sup_depth = sup->super_depth();
228 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
229 if (!can_be_primary_super_slow())
230 my_depth = primary_super_limit();
231 for (juint i = 0; i < my_depth; i++) {
232 _primary_supers[i] = sup->_primary_supers[i];
233 }
234 Klass* *super_check_cell;
235 if (my_depth < primary_super_limit()) {
236 _primary_supers[my_depth] = this;
237 super_check_cell = &_primary_supers[my_depth];
238 } else {
239 // Overflow of the primary_supers array forces me to be secondary.
240 super_check_cell = &_secondary_super_cache;
241 }
242 set_super_check_offset((address)super_check_cell - (address) this);
243
244 #ifdef ASSERT
245 {
246 juint j = super_depth();
247 assert(j == my_depth, "computed accessor gets right answer");
248 Klass* t = this;
249 while (!t->can_be_primary_super()) {
250 t = t->super();
251 j = t->super_depth();
252 }
253 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
254 assert(primary_super_of_depth(j1) == NULL, "super list padding");
255 }
256 while (t != NULL) {
257 assert(primary_super_of_depth(j) == t, "super list initialization");
258 t = t->super();
259 --j;
260 }
261 assert(j == (juint)-1, "correct depth count");
262 }
263 #endif
264 }
265
266 if (secondary_supers() == NULL) {
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 = 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 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 InstanceKlass* Klass::superklass() const {
338 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
339 return _super == NULL ? NULL : InstanceKlass::cast(_super);
340 }
341
342 void Klass::set_subklass(Klass* s) {
343 assert(s != this, "sanity check");
344 _subklass = s;
345 }
346
347 void Klass::set_next_sibling(Klass* s) {
348 assert(s != this, "sanity check");
349 _next_sibling = s;
350 }
351
352 void Klass::append_to_sibling_list() {
353 debug_only(verify();)
354 // add ourselves to superklass' subklass list
355 InstanceKlass* super = superklass();
356 if (super == NULL) return; // special case: class Object
357 assert((!super->is_interface() // interfaces cannot be supers
358 && (super->superklass() == NULL || !is_interface())),
359 "an interface can only be a subklass of Object");
360 Klass* prev_first_subklass = super->subklass();
361 if (prev_first_subklass != NULL) {
362 // set our sibling to be the superklass' previous first subklass
363 set_next_sibling(prev_first_subklass);
364 }
365 // make ourselves the superklass' first subklass
366 super->set_subklass(this);
367 debug_only(verify();)
368 }
369
370 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
371 #ifdef ASSERT
372 // The class is alive iff the class loader is alive.
373 oop loader = class_loader();
374 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
375 #endif // ASSERT
376
377 // The class is alive if it's mirror is alive (which should be marked if the
378 // loader is alive) unless it's an anoymous class.
379 bool mirror_alive = is_alive->do_object_b(java_mirror());
380 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
381 " but not the other way around with anonymous classes");
382 return mirror_alive;
383 }
384
385 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
386 if (!ClassUnloading) {
387 return;
388 }
389
390 Klass* root = SystemDictionary::Object_klass();
391 Stack<Klass*, mtGC> stack;
392
393 stack.push(root);
394 while (!stack.is_empty()) {
395 Klass* current = stack.pop();
396
397 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
398
399 // Find and set the first alive subklass
400 Klass* sub = current->subklass();
401 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
402 #ifndef PRODUCT
403 if (log_is_enabled(Trace, class, unload)) {
404 ResourceMark rm;
405 log_trace(class, unload)("unlinking class (subclass): %s", sub->external_name());
406 }
407 #endif
408 sub = sub->next_sibling();
409 }
410 current->set_subklass(sub);
411 if (sub != NULL) {
412 stack.push(sub);
413 }
414
415 // Find and set the first alive sibling
416 Klass* sibling = current->next_sibling();
417 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
418 if (log_is_enabled(Trace, class, unload)) {
419 ResourceMark rm;
420 log_trace(class, unload)("[Unlinking class (sibling) %s]", sibling->external_name());
421 }
422 sibling = sibling->next_sibling();
423 }
424 current->set_next_sibling(sibling);
425 if (sibling != NULL) {
426 stack.push(sibling);
427 }
428
429 // Clean the implementors list and method data.
430 if (clean_alive_klasses && current->is_instance_klass()) {
431 InstanceKlass* ik = InstanceKlass::cast(current);
432 ik->clean_weak_instanceklass_links(is_alive);
433
434 // JVMTI RedefineClasses creates previous versions that are not in
435 // the class hierarchy, so process them here.
436 while ((ik = ik->previous_versions()) != NULL) {
437 ik->clean_weak_instanceklass_links(is_alive);
438 }
439 }
440 }
441 }
442
443 void Klass::klass_oop_store(oop* p, oop v) {
444 assert(!GC::gc()->heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
445 assert(v == NULL || GC::gc()->heap()->is_in_reserved((void*)v), "Should store pointer to an object");
446
447 // do the store
448 oopDesc::bs()->klass_oop_store(p, v);
449 record_modified_oops();
450 }
451
452 void Klass::klass_oop_store(volatile oop* p, oop v) {
453 assert(!GC::gc()->heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
454 assert(v == NULL || GC::gc()->heap()->is_in_reserved((void*)v), "Should store pointer to an object");
455
456 oopDesc::bs()->klass_oop_store(p, v);
457 record_modified_oops();
458 }
459
460 void Klass::oops_do(OopClosure* cl) {
461 cl->do_oop(&_java_mirror);
462 }
463
464 void Klass::remove_unshareable_info() {
465 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
466 TRACE_REMOVE_ID(this);
467
468 set_subklass(NULL);
469 set_next_sibling(NULL);
470 // Clear the java mirror
471 set_java_mirror(NULL);
472 set_next_link(NULL);
473
474 // Null out class_loader_data because we don't share that yet.
475 set_class_loader_data(NULL);
476 }
477
478 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
479 assert(is_klass(), "ensure C++ vtable is restored");
480 TRACE_RESTORE_ID(this);
481
482 // If an exception happened during CDS restore, some of these fields may already be
483 // set. We leave the class on the CLD list, even if incomplete so that we don't
484 // modify the CLD list outside a safepoint.
485 if (class_loader_data() == NULL) {
486 // Restore class_loader_data to the null class loader data
487 set_class_loader_data(loader_data);
488
489 // Add to null class loader list first before creating the mirror
490 // (same order as class file parsing)
491 loader_data->add_class(this);
492 }
493
494 // Recreate the class mirror.
495 // Only recreate it if not present. A previous attempt to restore may have
496 // gotten an OOM later but keep the mirror if it was created.
497 if (java_mirror() == NULL) {
498 Handle loader(THREAD, loader_data->class_loader());
499 ModuleEntry* module_entry = NULL;
500 Klass* k = this;
501 if (k->is_objArray_klass()) {
502 k = ObjArrayKlass::cast(k)->bottom_klass();
503 }
504 // Obtain klass' module.
505 if (k->is_instance_klass()) {
506 InstanceKlass* ik = (InstanceKlass*) k;
507 module_entry = ik->module();
508 } else {
509 module_entry = ModuleEntryTable::javabase_moduleEntry();
510 }
511 // Obtain java.lang.reflect.Module, if available
512 Handle module_handle(THREAD, ((module_entry != NULL) ? JNIHandles::resolve(module_entry->module()) : (oop)NULL));
513 java_lang_Class::create_mirror(this, loader, module_handle, protection_domain, CHECK);
514 }
515 }
516
517 Klass* Klass::array_klass_or_null(int rank) {
518 EXCEPTION_MARK;
519 // No exception can be thrown by array_klass_impl when called with or_null == true.
520 // (In anycase, the execption mark will fail if it do so)
521 return array_klass_impl(true, rank, THREAD);
522 }
523
524
525 Klass* Klass::array_klass_or_null() {
526 EXCEPTION_MARK;
527 // No exception can be thrown by array_klass_impl when called with or_null == true.
528 // (In anycase, the execption mark will fail if it do so)
529 return array_klass_impl(true, THREAD);
530 }
531
532
533 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
534 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
535 return NULL;
536 }
537
538
539 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
540 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
541 return NULL;
542 }
543
544 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
545
546 // In product mode, this function doesn't have virtual function calls so
547 // there might be some performance advantage to handling InstanceKlass here.
548 const char* Klass::external_name() const {
549 if (is_instance_klass()) {
550 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
551 if (ik->is_anonymous()) {
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) {
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(Metaspace::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 klassVtable* Klass::vtable() const {
676 return new klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
677 }
678
679 vtableEntry* Klass::start_of_vtable() const {
680 return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
681 }
682
683 Method* Klass::method_at_vtable(int index) {
684 #ifndef PRODUCT
685 assert(index >= 0, "valid vtable index");
686 if (DebugVtables) {
687 verify_vtable_index(index);
688 }
689 #endif
690 return start_of_vtable()[index].method();
691 }
692
693 ByteSize Klass::vtable_start_offset() {
694 return in_ByteSize(InstanceKlass::header_size() * wordSize);
695 }
696
697 #ifndef PRODUCT
698
699 bool Klass::verify_vtable_index(int i) {
700 int limit = vtable_length()/vtableEntry::size();
701 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
702 return true;
703 }
704
705 bool Klass::verify_itable_index(int i) {
706 assert(is_instance_klass(), "");
707 int method_count = klassItable::method_count_for_interface(this);
708 assert(i >= 0 && i < method_count, "index out of bounds");
709 return true;
710 }
711
712 #endif