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/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 bool Klass::is_cloneable() const {
48 return _access_flags.is_cloneable_fast() ||
49 is_subtype_of(SystemDictionary::Cloneable_klass());
50 }
51
52 void Klass::set_is_cloneable() {
53 if (name() != vmSymbols::java_lang_invoke_MemberName()) {
54 _access_flags.set_is_cloneable_fast();
55 } else {
56 assert(is_final(), "no subclasses allowed");
57 // MemberName cloning should not be intrinsified and always happen in JVM_Clone.
58 }
59 }
60
61 void Klass::set_name(Symbol* n) {
62 _name = n;
63 if (_name != NULL) _name->increment_refcount();
64 }
65
66 bool Klass::is_subclass_of(const Klass* k) const {
67 // Run up the super chain and check
68 if (this == k) return true;
69
70 Klass* t = const_cast<Klass*>(this)->super();
71
72 while (t != NULL) {
73 if (t == k) return true;
74 t = t->super();
75 }
76 return false;
77 }
78
79 bool Klass::search_secondary_supers(Klass* k) const {
80 // Put some extra logic here out-of-line, before the search proper.
81 // This cuts down the size of the inline method.
82
83 // This is necessary, since I am never in my own secondary_super list.
84 if (this == k)
85 return true;
86 // Scan the array-of-objects for a match
87 int cnt = secondary_supers()->length();
88 for (int i = 0; i < cnt; i++) {
89 if (secondary_supers()->at(i) == k) {
90 ((Klass*)this)->set_secondary_super_cache(k);
91 return true;
92 }
93 }
94 return false;
95 }
96
97 // Return self, except for abstract classes with exactly 1
98 // implementor. Then return the 1 concrete implementation.
99 Klass *Klass::up_cast_abstract() {
100 Klass *r = this;
101 while( r->is_abstract() ) { // Receiver is abstract?
102 Klass *s = r->subklass(); // Check for exactly 1 subklass
103 if( !s || s->next_sibling() ) // Oops; wrong count; give up
104 return this; // Return 'this' as a no-progress flag
105 r = s; // Loop till find concrete class
106 }
107 return r; // Return the 1 concrete class
108 }
109
110 // Find LCA in class hierarchy
111 Klass *Klass::LCA( Klass *k2 ) {
112 Klass *k1 = this;
113 while( 1 ) {
114 if( k1->is_subtype_of(k2) ) return k2;
115 if( k2->is_subtype_of(k1) ) return k1;
116 k1 = k1->super();
117 k2 = k2->super();
118 }
119 }
120
121
122 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
123 ResourceMark rm(THREAD);
124 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
125 : vmSymbols::java_lang_InstantiationException(), external_name());
126 }
127
128
129 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
130 THROW(vmSymbols::java_lang_ArrayStoreException());
131 }
132
133
134 void Klass::initialize(TRAPS) {
135 ShouldNotReachHere();
136 }
137
138 bool Klass::compute_is_subtype_of(Klass* k) {
139 assert(k->is_klass(), "argument must be a class");
140 return is_subclass_of(k);
141 }
142
143 Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
144 #ifdef ASSERT
145 tty->print_cr("Error: find_field called on a klass oop."
146 " Likely error: reflection method does not correctly"
147 " wrap return value in a mirror object.");
148 #endif
149 ShouldNotReachHere();
150 return NULL;
151 }
152
153 Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature, OverpassLookupMode overpass_mode) const {
154 #ifdef ASSERT
155 tty->print_cr("Error: uncached_lookup_method 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 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
164 return Metaspace::allocate(loader_data, word_size, MetaspaceObj::ClassType, THREAD);
165 }
166
167 // "Normal" instantiation is preceeded by a MetaspaceObj allocation
168 // which zeros out memory - calloc equivalent.
169 // The constructor is also used from CppVtableCloner,
170 // which doesn't zero out the memory before calling the constructor.
171 // Need to set the _java_mirror field explicitly to not hit an assert that the field
172 // should be NULL before setting it.
173 Klass::Klass() : _prototype_header(markOopDesc::prototype()),
174 _shared_class_path_index(-1),
175 _java_mirror(NULL) {
176
177 _primary_supers[0] = this;
178 set_super_check_offset(in_bytes(primary_supers_offset()));
179 }
180
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));
189
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");
197
198 return lh;
199 }
200
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 }
209
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);
241
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 }
263
264 if (secondary_supers() == NULL) {
265
266 // Now compute the list of secondary supertypes.
267 // Secondaries can occasionally be on the super chain,
268 // if the inline "_primary_supers" array overflows.
269 int extras = 0;
270 Klass* p;
271 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
272 ++extras;
273 }
274
275 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
276
277 // Compute the "real" non-extra secondaries.
278 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
279 if (secondaries == NULL) {
280 // secondary_supers set by compute_secondary_supers
281 return;
282 }
283
284 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
285
286 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
287 int i; // Scan for overflow primaries being duplicates of 2nd'arys
288
289 // This happens frequently for very deeply nested arrays: the
290 // primary superclass chain overflows into the secondary. The
291 // secondary list contains the element_klass's secondaries with
292 // an extra array dimension added. If the element_klass's
293 // secondary list already contains some primary overflows, they
294 // (with the extra level of array-ness) will collide with the
295 // normal primary superclass overflows.
296 for( i = 0; i < secondaries->length(); i++ ) {
297 if( secondaries->at(i) == p )
298 break;
299 }
300 if( i < secondaries->length() )
301 continue; // It's a dup, don't put it in
302 primaries->push(p);
303 }
304 // Combine the two arrays into a metadata object to pack the array.
305 // The primaries are added in the reverse order, then the secondaries.
306 int new_length = primaries->length() + secondaries->length();
307 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
308 class_loader_data(), new_length, CHECK);
309 int fill_p = primaries->length();
310 for (int j = 0; j < fill_p; j++) {
311 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
312 }
313 for( int j = 0; j < secondaries->length(); j++ ) {
314 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
315 }
316
317 #ifdef ASSERT
318 // We must not copy any NULL placeholders left over from bootstrap.
319 for (int j = 0; j < s2->length(); j++) {
320 assert(s2->at(j) != NULL, "correct bootstrapping order");
321 }
322 #endif
323
324 set_secondary_supers(s2);
325 }
326 }
327
328 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
329 assert(num_extra_slots == 0, "override for complex klasses");
330 set_secondary_supers(Universe::the_empty_klass_array());
331 return NULL;
332 }
333
334
335 InstanceKlass* Klass::superklass() const {
336 assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
337 return _super == NULL ? NULL : InstanceKlass::cast(_super);
338 }
339
340 void Klass::set_subklass(Klass* s) {
341 assert(s != this, "sanity check");
342 _subklass = s;
343 }
344
345 void Klass::set_next_sibling(Klass* s) {
346 assert(s != this, "sanity check");
347 _next_sibling = s;
348 }
349
350 void Klass::append_to_sibling_list() {
351 debug_only(verify();)
352 // add ourselves to superklass' subklass list
353 InstanceKlass* super = superklass();
354 if (super == NULL) return; // special case: class Object
355 assert((!super->is_interface() // interfaces cannot be supers
356 && (super->superklass() == NULL || !is_interface())),
357 "an interface can only be a subklass of Object");
358 Klass* prev_first_subklass = super->subklass();
359 if (prev_first_subklass != NULL) {
360 // set our sibling to be the superklass' previous first subklass
361 set_next_sibling(prev_first_subklass);
362 }
363 // make ourselves the superklass' first subklass
364 super->set_subklass(this);
365 debug_only(verify();)
366 }
367
368 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
369 #ifdef ASSERT
370 // The class is alive iff the class loader is alive.
371 oop loader = class_loader();
372 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
373 #endif // ASSERT
374
375 // The class is alive if it's mirror is alive (which should be marked if the
376 // loader is alive) unless it's an anoymous class.
377 bool mirror_alive = is_alive->do_object_b(java_mirror());
378 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
379 " but not the other way around with anonymous classes");
380 return mirror_alive;
381 }
382
383 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
384 if (!ClassUnloading) {
385 return;
386 }
387
388 Klass* root = SystemDictionary::Object_klass();
389 Stack<Klass*, mtGC> stack;
390
391 stack.push(root);
392 while (!stack.is_empty()) {
393 Klass* current = stack.pop();
394
395 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
396
397 // Find and set the first alive subklass
398 Klass* sub = current->subklass();
399 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
400 #ifndef PRODUCT
401 if (log_is_enabled(Trace, class, unload)) {
402 ResourceMark rm;
403 log_trace(class, unload)("unlinking class (subclass): %s", sub->external_name());
404 }
405 #endif
406 sub = sub->next_sibling();
407 }
408 current->set_subklass(sub);
409 if (sub != NULL) {
410 stack.push(sub);
411 }
412
413 // Find and set the first alive sibling
414 Klass* sibling = current->next_sibling();
415 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
416 if (log_is_enabled(Trace, class, unload)) {
417 ResourceMark rm;
418 log_trace(class, unload)("[Unlinking class (sibling) %s]", sibling->external_name());
419 }
420 sibling = sibling->next_sibling();
421 }
422 current->set_next_sibling(sibling);
423 if (sibling != NULL) {
424 stack.push(sibling);
425 }
426
427 // Clean the implementors list and method data.
428 if (clean_alive_klasses && current->is_instance_klass()) {
429 InstanceKlass* ik = InstanceKlass::cast(current);
430 ik->clean_weak_instanceklass_links(is_alive);
431
432 // JVMTI RedefineClasses creates previous versions that are not in
433 // the class hierarchy, so process them here.
434 while ((ik = ik->previous_versions()) != NULL) {
435 ik->clean_weak_instanceklass_links(is_alive);
436 }
437 }
438 }
439 }
440
441 void Klass::klass_update_barrier_set(oop v) {
442 record_modified_oops();
443 }
444
445 // This barrier is used by G1 to remember the old oop values, so
446 // that we don't forget any objects that were live at the snapshot at
447 // the beginning. This function is only used when we write oops into Klasses.
448 void Klass::klass_update_barrier_set_pre(oop* p, oop v) {
449 #if INCLUDE_ALL_GCS
450 oop obj = oopDesc::load_heap_oop(p);
451 if (! oopDesc::is_null(obj)) {
452 oopDesc::bs()->keep_alive_barrier(obj);
453 }
454 #endif
455 }
456
457 void Klass::klass_oop_store(oop* p, oop v) {
458 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
459 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
460
461 // do the store
462 if (always_do_update_barrier) {
463 klass_oop_store((volatile oop*)p, v);
464 } else {
465 klass_update_barrier_set_pre(p, v);
466 *p = v;
467 klass_update_barrier_set(v);
468 }
469 }
470
471 void Klass::klass_oop_store(volatile oop* p, oop v) {
472 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
473 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
474
475 klass_update_barrier_set_pre((oop*)p, v); // Cast away volatile.
476 OrderAccess::release_store_ptr(p, v);
477 klass_update_barrier_set(v);
478 }
479
480 void Klass::oops_do(OopClosure* cl) {
481 cl->do_oop(&_java_mirror);
482 }
483
484 void Klass::metaspace_pointers_do(MetaspaceClosure* it) {
485 if (log_is_enabled(Trace, cds)) {
486 ResourceMark rm;
487 log_trace(cds)("Iter(Klass): %p (%s)", this, external_name());
488 }
489
490 it->push(&_name);
491 it->push(&_secondary_super_cache);
492 it->push(&_secondary_supers);
493 for (int i = 0; i < _primary_super_limit; i++) {
494 it->push(&_primary_supers[i]);
495 }
496 it->push(&_super);
497 it->push(&_subklass);
498 it->push(&_next_sibling);
499 it->push(&_next_link);
500
501 vtableEntry* vt = start_of_vtable();
502 for (int i=0; i<vtable_length(); i++) {
503 it->push(vt[i].method_addr());
504 }
505 }
506
507 void Klass::remove_unshareable_info() {
508 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
509 TRACE_REMOVE_ID(this);
510
511 set_subklass(NULL);
512 set_next_sibling(NULL);
513 // Clear the java mirror
514 set_java_mirror(NULL);
515 set_next_link(NULL);
516
517 // Null out class_loader_data because we don't share that yet.
518 set_class_loader_data(NULL);
519 set_is_shared();
520 }
521
522 void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
523 assert(is_klass(), "ensure C++ vtable is restored");
524 assert(is_shared(), "must be set");
525 TRACE_RESTORE_ID(this);
526
527 // If an exception happened during CDS restore, some of these fields may already be
528 // set. We leave the class on the CLD list, even if incomplete so that we don't
529 // modify the CLD list outside a safepoint.
530 if (class_loader_data() == NULL) {
531 // Restore class_loader_data to the null class loader data
532 set_class_loader_data(loader_data);
533
534 // Add to null class loader list first before creating the mirror
535 // (same order as class file parsing)
536 loader_data->add_class(this);
537 }
538
539 // Recreate the class mirror.
540 // Only recreate it if not present. A previous attempt to restore may have
541 // gotten an OOM later but keep the mirror if it was created.
542 if (java_mirror() == NULL) {
543 Handle loader(THREAD, loader_data->class_loader());
544 ModuleEntry* module_entry = NULL;
545 Klass* k = this;
546 if (k->is_objArray_klass()) {
547 k = ObjArrayKlass::cast(k)->bottom_klass();
548 }
549 // Obtain klass' module.
550 if (k->is_instance_klass()) {
551 InstanceKlass* ik = (InstanceKlass*) k;
552 module_entry = ik->module();
553 } else {
554 module_entry = ModuleEntryTable::javabase_moduleEntry();
555 }
556 // Obtain java.lang.Module, if available
557 Handle module_handle(THREAD, ((module_entry != NULL) ? module_entry->module() : (oop)NULL));
558 java_lang_Class::create_mirror(this, loader, module_handle, protection_domain, CHECK);
559 }
560 }
561
562 Klass* Klass::array_klass_or_null(int rank) {
563 EXCEPTION_MARK;
564 // No exception can be thrown by array_klass_impl when called with or_null == true.
565 // (In anycase, the execption mark will fail if it do so)
566 return array_klass_impl(true, rank, THREAD);
567 }
568
569
570 Klass* Klass::array_klass_or_null() {
571 EXCEPTION_MARK;
572 // No exception can be thrown by array_klass_impl when called with or_null == true.
573 // (In anycase, the execption mark will fail if it do so)
574 return array_klass_impl(true, THREAD);
575 }
576
577
578 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
579 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
580 return NULL;
581 }
582
583
584 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
585 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
586 return NULL;
587 }
588
589 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
590
591 // In product mode, this function doesn't have virtual function calls so
592 // there might be some performance advantage to handling InstanceKlass here.
593 const char* Klass::external_name() const {
594 if (is_instance_klass()) {
595 const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
596 if (ik->is_anonymous()) {
597 intptr_t hash = 0;
598 if (ik->java_mirror() != NULL) {
599 // java_mirror might not be created yet, return 0 as hash.
600 hash = ik->java_mirror()->identity_hash();
601 }
602 char hash_buf[40];
603 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
604 size_t hash_len = strlen(hash_buf);
605
606 size_t result_len = name()->utf8_length();
607 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
608 name()->as_klass_external_name(result, (int) result_len + 1);
609 assert(strlen(result) == result_len, "");
610 strcpy(result + result_len, hash_buf);
611 assert(strlen(result) == result_len + hash_len, "");
612 return result;
613 }
614 }
615 if (name() == NULL) return "<unknown>";
616 return name()->as_klass_external_name();
617 }
618
619
620 const char* Klass::signature_name() const {
621 if (name() == NULL) return "<unknown>";
622 return name()->as_C_string();
623 }
624
625 // Unless overridden, modifier_flags is 0.
626 jint Klass::compute_modifier_flags(TRAPS) const {
627 return 0;
628 }
629
630 int Klass::atomic_incr_biased_lock_revocation_count() {
631 return (int) Atomic::add(1, &_biased_lock_revocation_count);
632 }
633
634 // Unless overridden, jvmti_class_status has no flags set.
635 jint Klass::jvmti_class_status() const {
636 return 0;
637 }
638
639
640 // Printing
641
642 void Klass::print_on(outputStream* st) const {
643 ResourceMark rm;
644 // print title
645 st->print("%s", internal_name());
646 print_address_on(st);
647 st->cr();
648 }
649
650 void Klass::oop_print_on(oop obj, outputStream* st) {
651 ResourceMark rm;
652 // print title
653 st->print_cr("%s ", internal_name());
654 obj->print_address_on(st);
655
656 if (WizardMode) {
657 // print header
658 obj->mark()->print_on(st);
659 }
660
661 // print class
662 st->print(" - klass: ");
663 obj->klass()->print_value_on(st);
664 st->cr();
665 }
666
667 void Klass::oop_print_value_on(oop obj, outputStream* st) {
668 // print title
669 ResourceMark rm; // Cannot print in debug mode without this
670 st->print("%s", internal_name());
671 obj->print_address_on(st);
672 }
673
674 #if INCLUDE_SERVICES
675 // Size Statistics
676 void Klass::collect_statistics(KlassSizeStats *sz) const {
677 sz->_klass_bytes = sz->count(this);
678 sz->_mirror_bytes = sz->count(java_mirror());
679 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
680
681 sz->_ro_bytes += sz->_secondary_supers_bytes;
682 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
683 }
684 #endif // INCLUDE_SERVICES
685
686 // Verification
687
688 void Klass::verify_on(outputStream* st) {
689
690 // This can be expensive, but it is worth checking that this klass is actually
691 // in the CLD graph but not in production.
692 assert(Metaspace::contains((address)this), "Should be");
693
694 guarantee(this->is_klass(),"should be klass");
695
696 if (super() != NULL) {
697 guarantee(super()->is_klass(), "should be klass");
698 }
699 if (secondary_super_cache() != NULL) {
700 Klass* ko = secondary_super_cache();
701 guarantee(ko->is_klass(), "should be klass");
702 }
703 for ( uint i = 0; i < primary_super_limit(); i++ ) {
704 Klass* ko = _primary_supers[i];
705 if (ko != NULL) {
706 guarantee(ko->is_klass(), "should be klass");
707 }
708 }
709
710 if (java_mirror() != NULL) {
711 guarantee(java_mirror()->is_oop(), "should be instance");
712 }
713 }
714
715 void Klass::oop_verify_on(oop obj, outputStream* st) {
716 guarantee(obj->is_oop(), "should be oop");
717 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
718 }
719
720 klassVtable Klass::vtable() const {
721 return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
722 }
723
724 vtableEntry* Klass::start_of_vtable() const {
725 return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
726 }
727
728 Method* Klass::method_at_vtable(int index) {
729 #ifndef PRODUCT
730 assert(index >= 0, "valid vtable index");
731 if (DebugVtables) {
732 verify_vtable_index(index);
733 }
734 #endif
735 return start_of_vtable()[index].method();
736 }
737
738 ByteSize Klass::vtable_start_offset() {
739 return in_ByteSize(InstanceKlass::header_size() * wordSize);
740 }
741
742 #ifndef PRODUCT
743
744 bool Klass::verify_vtable_index(int i) {
745 int limit = vtable_length()/vtableEntry::size();
746 assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
747 return true;
748 }
749
750 bool Klass::verify_itable_index(int i) {
751 assert(is_instance_klass(), "");
752 int method_count = klassItable::method_count_for_interface(this);
753 assert(i >= 0 && i < method_count, "index out of bounds");
754 return true;
755 }
756
757 #endif