1 /*
2 * Copyright (c) 1997, 2018, 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/metaspaceClosure.hpp"
35 #include "memory/metaspaceShared.hpp"
36 #include "memory/oopFactory.hpp"
37 #include "memory/resourceArea.hpp"
38 #include "oops/instanceKlass.hpp"
39 #include "oops/klass.inline.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "runtime/atomic.hpp"
42 #include "runtime/orderAccess.inline.hpp"
43 #include "trace/traceMacros.hpp"
44 #include "utilities/macros.hpp"
45 #include "utilities/stack.inline.hpp"
46
47 void Klass::set_java_mirror(Handle m) {
48 assert(!m.is_null(), "New mirror should never be null.");
49 assert(_java_mirror.resolve() == NULL, "should only be used to initialize mirror");
50 _java_mirror = class_loader_data()->add_handle(m);
51 }
52
53 oop Klass::java_mirror() const {
54 return _java_mirror.resolve();
55 }
56
57 bool Klass::is_cloneable() const {
58 return _access_flags.is_cloneable_fast() ||
59 is_subtype_of(SystemDictionary::Cloneable_klass());
60 }
61
62 void Klass::set_is_cloneable() {
63 if (name() != vmSymbols::java_lang_invoke_MemberName()) {
64 _access_flags.set_is_cloneable_fast();
65 } else {
66 assert(is_final(), "no subclasses allowed");
67 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
68 }
69 }
70
71 void Klass::set_name(Symbol* n) {
72 _name = n;
73 if (_name != NULL) _name->increment_refcount();
74 }
75
76 bool Klass::is_subclass_of(const Klass* k) const {
77 // Run up the super chain and check
78 if (this == k) return true;
79
80 Klass* t = const_cast<Klass*>(this)->super();
81
82 while (t != NULL) {
83 if (t == k) return true;
84 t = t->super();
85 }
86 return false;
87 }
88
89 bool Klass::search_secondary_supers(Klass* k) const {
90 // Put some extra logic here out-of-line, before the search proper.
91 // This cuts down the size of the inline method.
92
93 // This is necessary, since I am never in my own secondary_super list.
94 if (this == k)
95 return true;
96 // Scan the array-of-objects for a match
97 int cnt = secondary_supers()->length();
98 for (int i = 0; i < cnt; i++) {
99 if (secondary_supers()->at(i) == k) {
100 ((Klass*)this)->set_secondary_super_cache(k);
101 return true;
102 }
103 }
104 return false;
105 }
106
107 // Return self, except for abstract classes with exactly 1
108 // implementor. Then return the 1 concrete implementation.
109 Klass *Klass::up_cast_abstract() {
110 Klass *r = this;
111 while( r->is_abstract() ) { // Receiver is abstract?
112 Klass *s = r->subklass(); // Check for exactly 1 subklass
113 if( !s || s->next_sibling() ) // Oops; wrong count; give up
114 return this; // Return 'this' as a no-progress flag
115 r = s; // Loop till find concrete class
116 }
117 return r; // Return the 1 concrete class
118 }
119
120 // Find LCA in class hierarchy
121 Klass *Klass::LCA( Klass *k2 ) {
122 Klass *k1 = this;
123 while( 1 ) {
124 if( k1->is_subtype_of(k2) ) return k2;
125 if( k2->is_subtype_of(k1) ) return k1;
126 k1 = k1->super();
127 k2 = k2->super();
128 }
129 }
130
131
132 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
133 ResourceMark rm(THREAD);
134 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
135 : vmSymbols::java_lang_InstantiationException(), external_name());
136 }
137
138
139 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
140 THROW(vmSymbols::java_lang_ArrayStoreException());
141 }
142
143
144 void Klass::initialize(TRAPS) {
145 ShouldNotReachHere();
146 }
147
148 bool Klass::compute_is_subtype_of(Klass* k) {
149 assert(k->is_klass(), "argument must be a class");
150 return is_subclass_of(k);
151 }
152
153 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
154 #ifdef ASSERT
155 tty->print_cr("Error: find_field called on a klass oop."
156 " Likely error: reflection method does not correctly"
157 " wrap return value in a mirror object.");
158 #endif
159 ShouldNotReachHere();
160 return NULL;
161 }
162
163 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const {
164 #ifdef ASSERT
165 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
166 " Likely error: reflection method does not correctly"
167 " wrap return value in a mirror object.");
168 #endif
169 ShouldNotReachHere();
170 return NULL;
171 }
172
173 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
174 return Metaspace::allocate(loader_data, word_size, MetaspaceObj::ClassType, THREAD);
175 }
176
177 // "Normal" instantiation is preceeded by a MetaspaceObj allocation
178 // which zeros out memory - calloc equivalent.
179 // The constructor is also used from CppVtableCloner,
180 // which doesn't zero out the memory before calling the constructor.
181 // Need to set the _java_mirror field explicitly to not hit an assert that the field
182 // should be NULL before setting it.
183 Klass::Klass() : _prototype_header(markOopDesc::prototype()),
184 _shared_class_path_index(-1),
185 _java_mirror(NULL) {
186
187 _primary_supers[0] = this;
188 set_super_check_offset(in_bytes(primary_supers_offset()));
189 }
190
191 jint Klass::array_layout_helper(BasicType etype) {
192 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
193 // Note that T_ARRAY is not allowed here.
194 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
195 int esize = type2aelembytes(etype);
196 bool isobj = (etype == T_OBJECT);
197 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
198 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
199
200 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
201 assert(layout_helper_is_array(lh), "correct kind");
202 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
203 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
204 assert(layout_helper_header_size(lh) == hsize, "correct decode");
205 assert(layout_helper_element_type(lh) == etype, "correct decode");
206 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
207
208 return lh;
209 }
210
211 bool Klass::can_be_primary_super_slow() const {
212 if (super() == NULL)
213 return true;
214 else if (super()->super_depth() >= primary_super_limit()-1)
215 return false;
216 else
217 return true;
218 }
219
220 void Klass::initialize_supers(Klass* k, TRAPS) {
221 if (FastSuperclassLimit == 0) {
222 // None of the other machinery matters.
223 set_super(k);
224 return;
225 }
226 if (k == NULL) {
227 set_super(NULL);
228 _primary_supers[0] = this;
229 assert(super_depth() == 0, "Object must already be initialized properly");
230 } else if (k != super() || k == SystemDictionary::Object_klass()) {
231 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
232 "initialize this only once to a non-trivial value");
233 set_super(k);
234 Klass* sup = k;
235 int sup_depth = sup->super_depth();
236 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
237 if (!can_be_primary_super_slow())
238 my_depth = primary_super_limit();
239 for (juint i = 0; i < my_depth; i++) {
240 _primary_supers[i] = sup->_primary_supers[i];
241 }
242 Klass* *super_check_cell;
243 if (my_depth < primary_super_limit()) {
244 _primary_supers[my_depth] = this;
245 super_check_cell = &_primary_supers[my_depth];
246 } else {
247 // Overflow of the primary_supers array forces me to be secondary.
248 super_check_cell = &_secondary_super_cache;
249 }
250 set_super_check_offset((address)super_check_cell - (address) this);
251
252 #ifdef ASSERT
253 {
254 juint j = super_depth();
255 assert(j == my_depth, "computed accessor gets right answer");
256 Klass* t = this;
257 while (!t->can_be_primary_super()) {
258 t = t->super();
259 j = t->super_depth();
260 }
261 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
262 assert(primary_super_of_depth(j1) == NULL, "super list padding");
263 }
264 while (t != NULL) {
265 assert(primary_super_of_depth(j) == t, "super list initialization");
266 t = t->super();
267 --j;
268 }
269 assert(j == (juint)-1, "correct depth count");
270 }
271 #endif
272 }
273
274 if (secondary_supers() == NULL) {
275
276 // Now compute the list of secondary supertypes.
277 // Secondaries can occasionally be on the super chain,
278 // if the inline "_primary_supers" array overflows.
279 int extras = 0;
280 Klass* p;
281 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
282 ++extras;
283 }
284
285 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
286
287 // Compute the "real" non-extra secondaries.
288 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
289 if (secondaries == NULL) {
290 // secondary_supers set by compute_secondary_supers
291 return;
292 }
293
294 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
295
296 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
297 int i; // Scan for overflow primaries being duplicates of 2nd'arys
298
299 // This happens frequently for very deeply nested arrays: the
300 // primary superclass chain overflows into the secondary. The
301 // secondary list contains the element_klass's secondaries with
302 // an extra array dimension added. If the element_klass's
303 // secondary list already contains some primary overflows, they
304 // (with the extra level of array-ness) will collide with the
305 // normal primary superclass overflows.
306 for( i = 0; i < secondaries->length(); i++ ) {
307 if( secondaries->at(i) == p )
308 break;
309 }
310 if( i < secondaries->length() )
311 continue; // It's a dup, don't put it in
312 primaries->push(p);
313 }
314 // Combine the two arrays into a metadata object to pack the array.
315 // The primaries are added in the reverse order, then the secondaries.
316 int new_length = primaries->length() + secondaries->length();
317 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
318 class_loader_data(), new_length, CHECK);
319 int fill_p = primaries->length();
320 for (int j = 0; j < fill_p; j++) {
321 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
322 }
323 for( int j = 0; j < secondaries->length(); j++ ) {
324 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
325 }
326
327 #ifdef ASSERT
328 // We must not copy any NULL placeholders left over from bootstrap.
329 for (int j = 0; j < s2->length(); j++) {
330 assert(s2->at(j) != NULL, "correct bootstrapping order");
331 }
332 #endif
333
334 set_secondary_supers(s2);
335 }
336 }
337
338 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
339 assert(num_extra_slots == 0, "override for complex klasses");
340 set_secondary_supers(Universe::the_empty_klass_array());
341 return NULL;
342 }
343
344
345 InstanceKlass* Klass::superklass() const {
346 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
347 return _super == NULL ? NULL : InstanceKlass::cast(_super);
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();
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 #ifdef ASSERT
380 // The class is alive iff the class loader is alive.
381 oop loader = class_loader();
382 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
383 #endif // ASSERT
384
385 // The class is alive if it's mirror is alive (which should be marked if the
386 // loader is alive) unless it's an anoymous class.
387 bool mirror_alive = is_alive->do_object_b(java_mirror());
388 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
389 " but not the other way around with anonymous classes");
390 return mirror_alive;
391 }
392
393 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
394 if (!ClassUnloading) {
395 return;
396 }
397
398 Klass* root = SystemDictionary::Object_klass();
399 Stack<Klass*, mtGC> stack;
400
401 stack.push(root);
402 while (!stack.is_empty()) {
403 Klass* current = stack.pop();
404
405 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
406
407 // Find and set the first alive subklass
408 Klass* sub = current->subklass();
409 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
410 #ifndef PRODUCT
411 if (log_is_enabled(Trace, class, unload)) {
412 ResourceMark rm;
413 log_trace(class, unload)("unlinking class (subclass): %s", sub->external_name());
414 }
415 #endif
416 sub = sub->next_sibling();
417 }
418 current->set_subklass(sub);
419 if (sub != NULL) {
420 stack.push(sub);
421 }
422
423 // Find and set the first alive sibling
424 Klass* sibling = current->next_sibling();
425 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
426 if (log_is_enabled(Trace, class, unload)) {
427 ResourceMark rm;
428 log_trace(class, unload)("[Unlinking class (sibling) %s]", sibling->external_name());
429 }
430 sibling = sibling->next_sibling();
431 }
432 current->set_next_sibling(sibling);
433 if (sibling != NULL) {
434 stack.push(sibling);
435 }
436
437 // Clean the implementors list and method data.
438 if (clean_alive_klasses && current->is_instance_klass()) {
439 InstanceKlass* ik = InstanceKlass::cast(current);
440 ik->clean_weak_instanceklass_links(is_alive);
441
442 // JVMTI RedefineClasses creates previous versions that are not in
443 // the class hierarchy, so process them here.
444 while ((ik = ik->previous_versions()) != NULL) {
445 ik->clean_weak_instanceklass_links(is_alive);
446 }
447 }
448 }
449 }
450
451 void Klass::metaspace_pointers_do(MetaspaceClosure* it) {
452 if (log_is_enabled(Trace, cds)) {
453 ResourceMark rm;
454 log_trace(cds)("Iter(Klass): %p (%s)", this, external_name());
455 }
456
457 it->push(&_name);
458 it->push(&_secondary_super_cache);
459 it->push(&_secondary_supers);
460 for (int i = 0; i < _primary_super_limit; i++) {
461 it->push(&_primary_supers[i]);
462 }
463 it->push(&_super);
464 it->push(&_subklass);
465 it->push(&_next_sibling);
466 it->push(&_next_link);
467
468 vtableEntry* vt = start_of_vtable();
469 for (int i=0; i<vtable_length(); i++) {
470 it->push(vt[i].method_addr());
471 }
472 }
473
474 void Klass::remove_unshareable_info() {
475 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
476 TRACE_REMOVE_ID(this);
477 if (log_is_enabled(Trace, cds, unshareable)) {
478 ResourceMark rm;
479 log_trace(cds, unshareable)("remove: %s", external_name());
480 }
481
482 set_subklass(NULL);
483 set_next_sibling(NULL);
484 set_next_link(NULL);
485
486 // Null out class_loader_data because we don't share that yet.
487 set_class_loader_data(NULL);
488 set_is_shared();
489 }
490
491 void Klass::remove_java_mirror() {
492 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
493 if (log_is_enabled(Trace, cds, unshareable)) {
494 ResourceMark rm;
495 log_trace(cds, unshareable)("remove java_mirror: %s", external_name());
496 }
497 // Just null out the mirror. The class_loader_data() no longer exists.
498 _java_mirror = NULL;
499 }
500
501 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
502 assert(is_klass(), "ensure C++ vtable is restored");
503 assert(is_shared(), "must be set");
504 TRACE_RESTORE_ID(this);
505 if (log_is_enabled(Trace, cds, unshareable)) {
506 ResourceMark rm;
507 log_trace(cds, unshareable)("restore: %s", external_name());
508 }
509
510 // If an exception happened during CDS restore, some of these fields may already be
511 // set. We leave the class on the CLD list, even if incomplete so that we don't
512 // modify the CLD list outside a safepoint.
513 if (class_loader_data() == NULL) {
514 // Restore class_loader_data to the null class loader data
515 set_class_loader_data(loader_data);
516
517 // Add to null class loader list first before creating the mirror
518 // (same order as class file parsing)
519 loader_data->add_class(this);
520 }
521
522 // Recreate the class mirror.
523 // Only recreate it if not present. A previous attempt to restore may have
524 // gotten an OOM later but keep the mirror if it was created.
525 if (java_mirror() == NULL) {
526 Handle loader(THREAD, loader_data->class_loader());
527 ModuleEntry* module_entry = NULL;
528 Klass* k = this;
529 if (k->is_objArray_klass()) {
530 k = ObjArrayKlass::cast(k)->bottom_klass();
531 }
532 // Obtain klass' module.
533 if (k->is_instance_klass()) {
534 InstanceKlass* ik = (InstanceKlass*) k;
535 module_entry = ik->module();
536 } else {
537 module_entry = ModuleEntryTable::javabase_moduleEntry();
538 }
539 // Obtain java.lang.Module, if available
540 Handle module_handle(THREAD, ((module_entry != NULL) ? module_entry->module() : (oop)NULL));
541 java_lang_Class::create_mirror(this, loader, module_handle, protection_domain, CHECK);
542 }
543 }
544
545 Klass* Klass::array_klass_or_null(int rank) {
546 EXCEPTION_MARK;
547 // No exception can be thrown by array_klass_impl when called with or_null == true.
548 // (In anycase, the execption mark will fail if it do so)
549 return array_klass_impl(true, rank, THREAD);
550 }
551
552
553 Klass* Klass::array_klass_or_null() {
554 EXCEPTION_MARK;
555 // No exception can be thrown by array_klass_impl when called with or_null == true.
556 // (In anycase, the execption mark will fail if it do so)
557 return array_klass_impl(true, THREAD);
558 }
559
560
561 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
562 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
563 return NULL;
564 }
565
566
567 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
568 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
569 return NULL;
570 }
571
572 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
573
574 // In product mode, this function doesn't have virtual function calls so
575 // there might be some performance advantage to handling InstanceKlass here.
576 const char* Klass::external_name() const {
577 if (is_instance_klass()) {
578 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
579 if (ik->is_anonymous()) {
580 intptr_t hash = 0;
581 if (ik->java_mirror() != NULL) {
582 // java_mirror might not be created yet, return 0 as hash.
583 hash = ik->java_mirror()->identity_hash();
584 }
585 char hash_buf[40];
586 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
587 size_t hash_len = strlen(hash_buf);
588
589 size_t result_len = name()->utf8_length();
590 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
591 name()->as_klass_external_name(result, (int) result_len + 1);
592 assert(strlen(result) == result_len, "");
593 strcpy(result + result_len, hash_buf);
594 assert(strlen(result) == result_len + hash_len, "");
595 return result;
596 }
597 }
598 if (name() == NULL) return "<unknown>";
599 return name()->as_klass_external_name();
600 }
601
602
603 const char* Klass::signature_name() const {
604 if (name() == NULL) return "<unknown>";
605 return name()->as_C_string();
606 }
607
608 // Unless overridden, modifier_flags is 0.
609 jint Klass::compute_modifier_flags(TRAPS) const {
610 return 0;
611 }
612
613 int Klass::atomic_incr_biased_lock_revocation_count() {
614 return (int) Atomic::add(1, &_biased_lock_revocation_count);
615 }
616
617 // Unless overridden, jvmti_class_status has no flags set.
618 jint Klass::jvmti_class_status() const {
619 return 0;
620 }
621
622 // Tell the GC to keep this klass alive
623 void Klass::ensure_klass_alive(oop o) {
624 // A klass that was previously considered dead can be looked up in the
625 // CLD/SD, and its _java_mirror or _class_loader can be stored in a root
626 // or a reachable object making it alive again.
627 // The SATB part of G1 needs to get notified about this
628 // potential resurrection, otherwise the marking might not find the object.
629 #if INCLUDE_ALL_GCS
630 if (UseG1GC && o != NULL) {
631 G1SATBCardTableModRefBS::enqueue(o);
632 }
633 #endif
634 }
635
636 // Printing
637
638 void Klass::print_on(outputStream* st) const {
639 ResourceMark rm;
640 // print title
641 st->print("%s", internal_name());
642 print_address_on(st);
643 st->cr();
644 }
645
646 void Klass::oop_print_on(oop obj, outputStream* st) {
647 ResourceMark rm;
648 // print title
649 st->print_cr("%s ", internal_name());
650 obj->print_address_on(st);
651
652 if (WizardMode) {
653 // print header
654 obj->mark()->print_on(st);
655 }
656
657 // print class
658 st->print(" - klass: ");
659 obj->klass()->print_value_on(st);
660 st->cr();
661 }
662
663 void Klass::oop_print_value_on(oop obj, outputStream* st) {
664 // print title
665 ResourceMark rm; // Cannot print in debug mode without this
666 st->print("%s", internal_name());
667 obj->print_address_on(st);
668 }
669
670 #if INCLUDE_SERVICES
671 // Size Statistics
672 void Klass::collect_statistics(KlassSizeStats *sz) const {
673 sz->_klass_bytes = sz->count(this);
674 sz->_mirror_bytes = sz->count(java_mirror());
675 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
676
677 sz->_ro_bytes += sz->_secondary_supers_bytes;
678 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
679 }
680 #endif // INCLUDE_SERVICES
681
682 // Verification
683
684 void Klass::verify_on(outputStream* st) {
685
686 // This can be expensive, but it is worth checking that this klass is actually
687 // in the CLD graph but not in production.
688 assert(Metaspace::contains((address)this), "Should be");
689
690 guarantee(this->is_klass(),"should be klass");
691
692 if (super() != NULL) {
693 guarantee(super()->is_klass(), "should be klass");
694 }
695 if (secondary_super_cache() != NULL) {
696 Klass* ko = secondary_super_cache();
697 guarantee(ko->is_klass(), "should be klass");
698 }
699 for ( uint i = 0; i < primary_super_limit(); i++ ) {
700 Klass* ko = _primary_supers[i];
701 if (ko != NULL) {
702 guarantee(ko->is_klass(), "should be klass");
703 }
704 }
705
706 if (java_mirror() != NULL) {
707 guarantee(oopDesc::is_oop(java_mirror()), "should be instance");
708 }
709 }
710
711 void Klass::oop_verify_on(oop obj, outputStream* st) {
712 guarantee(oopDesc::is_oop(obj), "should be oop");
713 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
714 }
715
716 klassVtable Klass::vtable() const {
717 return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
718 }
719
720 vtableEntry* Klass::start_of_vtable() const {
721 return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
722 }
723
724 Method* Klass::method_at_vtable(int index) {
725 #ifndef PRODUCT
726 assert(index >= 0, "valid vtable index");
727 if (DebugVtables) {
728 verify_vtable_index(index);
729 }
730 #endif
731 return start_of_vtable()[index].method();
732 }
733
734 ByteSize Klass::vtable_start_offset() {
735 return in_ByteSize(InstanceKlass::header_size() * wordSize);
736 }
737
738 #ifndef PRODUCT
739
740 bool Klass::verify_vtable_index(int i) {
741 int limit = vtable_length()/vtableEntry::size();
742 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
743 return true;
744 }
745
746 bool Klass::verify_itable_index(int i) {
747 assert(is_instance_klass(), "");
748 int method_count = klassItable::method_count_for_interface(this);
749 assert(i >= 0 && i < method_count, "index out of bounds");
750 return true;
751 }
752
753 #endif