src/share/vm/oops/klass.cpp

Mon, 07 Jul 2014 10:12:40 +0200

author
stefank
date
Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992
2c6ef90f030a
parent 6976
76b588255908
child 7089
6e0cb14ce59b
permissions
-rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

duke@435 1 /*
coleenp@6316 2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #include "precompiled.hpp"
coleenp@4037 26 #include "classfile/javaClasses.hpp"
coleenp@4037 27 #include "classfile/dictionary.hpp"
stefank@2314 28 #include "classfile/systemDictionary.hpp"
stefank@2314 29 #include "classfile/vmSymbols.hpp"
coleenp@4037 30 #include "gc_implementation/shared/markSweep.inline.hpp"
stefank@2314 31 #include "gc_interface/collectedHeap.inline.hpp"
acorn@4497 32 #include "memory/heapInspection.hpp"
coleenp@4037 33 #include "memory/metadataFactory.hpp"
stefank@2314 34 #include "memory/oopFactory.hpp"
stefank@2314 35 #include "memory/resourceArea.hpp"
stefank@2314 36 #include "oops/instanceKlass.hpp"
stefank@2314 37 #include "oops/klass.inline.hpp"
stefank@2314 38 #include "oops/oop.inline2.hpp"
goetz@6911 39 #include "runtime/atomic.inline.hpp"
goetz@6911 40 #include "runtime/orderAccess.inline.hpp"
sla@5237 41 #include "trace/traceMacros.hpp"
coleenp@4037 42 #include "utilities/stack.hpp"
jprovino@4542 43 #include "utilities/macros.hpp"
jprovino@4542 44 #if INCLUDE_ALL_GCS
stefank@6992 45 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
coleenp@4037 46 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
coleenp@4037 47 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
coleenp@4037 48 #include "gc_implementation/parallelScavenge/psScavenge.hpp"
jprovino@4542 49 #endif // INCLUDE_ALL_GCS
duke@435 50
coleenp@2497 51 void Klass::set_name(Symbol* n) {
coleenp@2497 52 _name = n;
coleenp@2497 53 if (_name != NULL) _name->increment_refcount();
coleenp@2497 54 }
duke@435 55
minqi@5097 56 bool Klass::is_subclass_of(const Klass* k) const {
duke@435 57 // Run up the super chain and check
coleenp@4037 58 if (this == k) return true;
duke@435 59
coleenp@4037 60 Klass* t = const_cast<Klass*>(this)->super();
duke@435 61
duke@435 62 while (t != NULL) {
duke@435 63 if (t == k) return true;
hseigel@4278 64 t = t->super();
duke@435 65 }
duke@435 66 return false;
duke@435 67 }
duke@435 68
coleenp@4037 69 bool Klass::search_secondary_supers(Klass* k) const {
duke@435 70 // Put some extra logic here out-of-line, before the search proper.
duke@435 71 // This cuts down the size of the inline method.
duke@435 72
duke@435 73 // This is necessary, since I am never in my own secondary_super list.
coleenp@4037 74 if (this == k)
duke@435 75 return true;
duke@435 76 // Scan the array-of-objects for a match
duke@435 77 int cnt = secondary_supers()->length();
duke@435 78 for (int i = 0; i < cnt; i++) {
coleenp@4037 79 if (secondary_supers()->at(i) == k) {
duke@435 80 ((Klass*)this)->set_secondary_super_cache(k);
duke@435 81 return true;
duke@435 82 }
duke@435 83 }
duke@435 84 return false;
duke@435 85 }
duke@435 86
duke@435 87 // Return self, except for abstract classes with exactly 1
duke@435 88 // implementor. Then return the 1 concrete implementation.
duke@435 89 Klass *Klass::up_cast_abstract() {
duke@435 90 Klass *r = this;
duke@435 91 while( r->is_abstract() ) { // Receiver is abstract?
duke@435 92 Klass *s = r->subklass(); // Check for exactly 1 subklass
duke@435 93 if( !s || s->next_sibling() ) // Oops; wrong count; give up
duke@435 94 return this; // Return 'this' as a no-progress flag
duke@435 95 r = s; // Loop till find concrete class
duke@435 96 }
duke@435 97 return r; // Return the 1 concrete class
duke@435 98 }
duke@435 99
twisti@1040 100 // Find LCA in class hierarchy
duke@435 101 Klass *Klass::LCA( Klass *k2 ) {
duke@435 102 Klass *k1 = this;
duke@435 103 while( 1 ) {
coleenp@4037 104 if( k1->is_subtype_of(k2) ) return k2;
coleenp@4037 105 if( k2->is_subtype_of(k1) ) return k1;
coleenp@4037 106 k1 = k1->super();
coleenp@4037 107 k2 = k2->super();
duke@435 108 }
duke@435 109 }
duke@435 110
duke@435 111
duke@435 112 void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
duke@435 113 ResourceMark rm(THREAD);
duke@435 114 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
duke@435 115 : vmSymbols::java_lang_InstantiationException(), external_name());
duke@435 116 }
duke@435 117
duke@435 118
duke@435 119 void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
duke@435 120 THROW(vmSymbols::java_lang_ArrayStoreException());
duke@435 121 }
duke@435 122
duke@435 123
duke@435 124 void Klass::initialize(TRAPS) {
duke@435 125 ShouldNotReachHere();
duke@435 126 }
duke@435 127
coleenp@4037 128 bool Klass::compute_is_subtype_of(Klass* k) {
duke@435 129 assert(k->is_klass(), "argument must be a class");
duke@435 130 return is_subclass_of(k);
duke@435 131 }
duke@435 132
duke@435 133
lfoltan@6632 134 Method* Klass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
duke@435 135 #ifdef ASSERT
duke@435 136 tty->print_cr("Error: uncached_lookup_method called on a klass oop."
duke@435 137 " Likely error: reflection method does not correctly"
duke@435 138 " wrap return value in a mirror object.");
duke@435 139 #endif
duke@435 140 ShouldNotReachHere();
duke@435 141 return NULL;
duke@435 142 }
duke@435 143
coleenp@5614 144 void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
coleenp@4037 145 return Metaspace::allocate(loader_data, word_size, /*read_only*/false,
iklam@5208 146 MetaspaceObj::ClassType, CHECK_NULL);
coleenp@4037 147 }
coleenp@4037 148
coleenp@4037 149 Klass::Klass() {
coleenp@4037 150 Klass* k = this;
duke@435 151
coleenp@4712 152 // Preinitialize supertype information.
coleenp@4712 153 // A later call to initialize_supers() may update these settings:
coleenp@4712 154 set_super(NULL);
coleenp@4712 155 for (juint i = 0; i < Klass::primary_super_limit(); i++) {
coleenp@4712 156 _primary_supers[i] = NULL;
duke@435 157 }
coleenp@4712 158 set_secondary_supers(NULL);
coleenp@4712 159 set_secondary_super_cache(NULL);
coleenp@4712 160 _primary_supers[0] = k;
coleenp@4712 161 set_super_check_offset(in_bytes(primary_supers_offset()));
duke@435 162
stefank@6992 163 // The constructor is used from init_self_patching_vtbl_list,
stefank@6992 164 // which doesn't zero out the memory before calling the constructor.
stefank@6992 165 // Need to set the field explicitly to not hit an assert that the field
stefank@6992 166 // should be NULL before setting it.
stefank@6992 167 _java_mirror = NULL;
stefank@6992 168
coleenp@4037 169 set_modifier_flags(0);
coleenp@4037 170 set_layout_helper(Klass::_lh_neutral_value);
coleenp@4037 171 set_name(NULL);
duke@435 172 AccessFlags af;
duke@435 173 af.set_flags(0);
coleenp@4037 174 set_access_flags(af);
coleenp@4037 175 set_subklass(NULL);
coleenp@4037 176 set_next_sibling(NULL);
coleenp@4037 177 set_next_link(NULL);
sla@5237 178 TRACE_INIT_ID(this);
duke@435 179
coleenp@4037 180 set_prototype_header(markOopDesc::prototype());
coleenp@4037 181 set_biased_lock_revocation_count(0);
coleenp@4037 182 set_last_biased_lock_bulk_revocation_time(0);
duke@435 183
coleenp@4037 184 // The klass doesn't have any references at this point.
coleenp@4037 185 clear_modified_oops();
coleenp@4037 186 clear_accumulated_modified_oops();
duke@435 187 }
duke@435 188
duke@435 189 jint Klass::array_layout_helper(BasicType etype) {
duke@435 190 assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
duke@435 191 // Note that T_ARRAY is not allowed here.
duke@435 192 int hsize = arrayOopDesc::base_offset_in_bytes(etype);
kvn@464 193 int esize = type2aelembytes(etype);
duke@435 194 bool isobj = (etype == T_OBJECT);
duke@435 195 int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
duke@435 196 int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
duke@435 197
duke@435 198 assert(lh < (int)_lh_neutral_value, "must look like an array layout");
coleenp@4037 199 assert(layout_helper_is_array(lh), "correct kind");
duke@435 200 assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
duke@435 201 assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
duke@435 202 assert(layout_helper_header_size(lh) == hsize, "correct decode");
duke@435 203 assert(layout_helper_element_type(lh) == etype, "correct decode");
duke@435 204 assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
duke@435 205
duke@435 206 return lh;
duke@435 207 }
duke@435 208
duke@435 209 bool Klass::can_be_primary_super_slow() const {
duke@435 210 if (super() == NULL)
duke@435 211 return true;
coleenp@4037 212 else if (super()->super_depth() >= primary_super_limit()-1)
duke@435 213 return false;
duke@435 214 else
duke@435 215 return true;
duke@435 216 }
duke@435 217
coleenp@4037 218 void Klass::initialize_supers(Klass* k, TRAPS) {
duke@435 219 if (FastSuperclassLimit == 0) {
duke@435 220 // None of the other machinery matters.
duke@435 221 set_super(k);
duke@435 222 return;
duke@435 223 }
duke@435 224 if (k == NULL) {
duke@435 225 set_super(NULL);
coleenp@4037 226 _primary_supers[0] = this;
duke@435 227 assert(super_depth() == 0, "Object must already be initialized properly");
never@1577 228 } else if (k != super() || k == SystemDictionary::Object_klass()) {
never@1577 229 assert(super() == NULL || super() == SystemDictionary::Object_klass(),
duke@435 230 "initialize this only once to a non-trivial value");
duke@435 231 set_super(k);
coleenp@4037 232 Klass* sup = k;
duke@435 233 int sup_depth = sup->super_depth();
duke@435 234 juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
duke@435 235 if (!can_be_primary_super_slow())
duke@435 236 my_depth = primary_super_limit();
duke@435 237 for (juint i = 0; i < my_depth; i++) {
coleenp@4037 238 _primary_supers[i] = sup->_primary_supers[i];
duke@435 239 }
coleenp@4037 240 Klass* *super_check_cell;
duke@435 241 if (my_depth < primary_super_limit()) {
coleenp@4037 242 _primary_supers[my_depth] = this;
duke@435 243 super_check_cell = &_primary_supers[my_depth];
duke@435 244 } else {
duke@435 245 // Overflow of the primary_supers array forces me to be secondary.
duke@435 246 super_check_cell = &_secondary_super_cache;
duke@435 247 }
coleenp@4037 248 set_super_check_offset((address)super_check_cell - (address) this);
duke@435 249
duke@435 250 #ifdef ASSERT
duke@435 251 {
duke@435 252 juint j = super_depth();
duke@435 253 assert(j == my_depth, "computed accessor gets right answer");
coleenp@4037 254 Klass* t = this;
hseigel@4278 255 while (!t->can_be_primary_super()) {
hseigel@4278 256 t = t->super();
hseigel@4278 257 j = t->super_depth();
duke@435 258 }
duke@435 259 for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
duke@435 260 assert(primary_super_of_depth(j1) == NULL, "super list padding");
duke@435 261 }
duke@435 262 while (t != NULL) {
duke@435 263 assert(primary_super_of_depth(j) == t, "super list initialization");
hseigel@4278 264 t = t->super();
duke@435 265 --j;
duke@435 266 }
duke@435 267 assert(j == (juint)-1, "correct depth count");
duke@435 268 }
duke@435 269 #endif
duke@435 270 }
duke@435 271
duke@435 272 if (secondary_supers() == NULL) {
duke@435 273 KlassHandle this_kh (THREAD, this);
duke@435 274
duke@435 275 // Now compute the list of secondary supertypes.
duke@435 276 // Secondaries can occasionally be on the super chain,
duke@435 277 // if the inline "_primary_supers" array overflows.
duke@435 278 int extras = 0;
coleenp@4037 279 Klass* p;
coleenp@4037 280 for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
duke@435 281 ++extras;
duke@435 282 }
duke@435 283
coleenp@4037 284 ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
coleenp@4037 285
duke@435 286 // Compute the "real" non-extra secondaries.
coleenp@4037 287 GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras);
coleenp@4037 288 if (secondaries == NULL) {
coleenp@4037 289 // secondary_supers set by compute_secondary_supers
coleenp@4037 290 return;
coleenp@4037 291 }
duke@435 292
coleenp@4037 293 GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
coleenp@4037 294
coleenp@4037 295 for (p = this_kh->super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
duke@435 296 int i; // Scan for overflow primaries being duplicates of 2nd'arys
duke@435 297
duke@435 298 // This happens frequently for very deeply nested arrays: the
duke@435 299 // primary superclass chain overflows into the secondary. The
duke@435 300 // secondary list contains the element_klass's secondaries with
duke@435 301 // an extra array dimension added. If the element_klass's
duke@435 302 // secondary list already contains some primary overflows, they
duke@435 303 // (with the extra level of array-ness) will collide with the
duke@435 304 // normal primary superclass overflows.
coleenp@4037 305 for( i = 0; i < secondaries->length(); i++ ) {
coleenp@4037 306 if( secondaries->at(i) == p )
duke@435 307 break;
coleenp@4037 308 }
duke@435 309 if( i < secondaries->length() )
duke@435 310 continue; // It's a dup, don't put it in
coleenp@4037 311 primaries->push(p);
duke@435 312 }
coleenp@4037 313 // Combine the two arrays into a metadata object to pack the array.
coleenp@4037 314 // The primaries are added in the reverse order, then the secondaries.
coleenp@4037 315 int new_length = primaries->length() + secondaries->length();
coleenp@4037 316 Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
coleenp@4037 317 class_loader_data(), new_length, CHECK);
coleenp@4037 318 int fill_p = primaries->length();
coleenp@4037 319 for (int j = 0; j < fill_p; j++) {
coleenp@4037 320 s2->at_put(j, primaries->pop()); // add primaries in reverse order.
coleenp@4037 321 }
coleenp@4037 322 for( int j = 0; j < secondaries->length(); j++ ) {
coleenp@4037 323 s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
duke@435 324 }
duke@435 325
duke@435 326 #ifdef ASSERT
duke@435 327 // We must not copy any NULL placeholders left over from bootstrap.
coleenp@4037 328 for (int j = 0; j < s2->length(); j++) {
coleenp@4037 329 assert(s2->at(j) != NULL, "correct bootstrapping order");
duke@435 330 }
duke@435 331 #endif
duke@435 332
coleenp@4037 333 this_kh->set_secondary_supers(s2);
duke@435 334 }
duke@435 335 }
duke@435 336
coleenp@4037 337 GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots) {
duke@435 338 assert(num_extra_slots == 0, "override for complex klasses");
coleenp@4037 339 set_secondary_supers(Universe::the_empty_klass_array());
coleenp@4037 340 return NULL;
duke@435 341 }
duke@435 342
duke@435 343
duke@435 344 Klass* Klass::subklass() const {
hseigel@4278 345 return _subklass == NULL ? NULL : _subklass;
duke@435 346 }
duke@435 347
coleenp@4037 348 InstanceKlass* Klass::superklass() const {
coleenp@4037 349 assert(super() == NULL || super()->oop_is_instance(), "must be instance klass");
coleenp@4037 350 return _super == NULL ? NULL : InstanceKlass::cast(_super);
duke@435 351 }
duke@435 352
duke@435 353 Klass* Klass::next_sibling() const {
hseigel@4278 354 return _next_sibling == NULL ? NULL : _next_sibling;
duke@435 355 }
duke@435 356
coleenp@4037 357 void Klass::set_subklass(Klass* s) {
coleenp@4037 358 assert(s != this, "sanity check");
coleenp@4037 359 _subklass = s;
duke@435 360 }
duke@435 361
coleenp@4037 362 void Klass::set_next_sibling(Klass* s) {
coleenp@4037 363 assert(s != this, "sanity check");
coleenp@4037 364 _next_sibling = s;
duke@435 365 }
duke@435 366
duke@435 367 void Klass::append_to_sibling_list() {
coleenp@4178 368 debug_only(verify();)
duke@435 369 // add ourselves to superklass' subklass list
coleenp@4037 370 InstanceKlass* super = superklass();
duke@435 371 if (super == NULL) return; // special case: class Object
coleenp@4178 372 assert((!super->is_interface() // interfaces cannot be supers
duke@435 373 && (super->superklass() == NULL || !is_interface())),
duke@435 374 "an interface can only be a subklass of Object");
coleenp@4037 375 Klass* prev_first_subklass = super->subklass_oop();
duke@435 376 if (prev_first_subklass != NULL) {
duke@435 377 // set our sibling to be the superklass' previous first subklass
duke@435 378 set_next_sibling(prev_first_subklass);
duke@435 379 }
duke@435 380 // make ourselves the superklass' first subklass
coleenp@4037 381 super->set_subklass(this);
coleenp@4178 382 debug_only(verify();)
duke@435 383 }
duke@435 384
coleenp@4037 385 bool Klass::is_loader_alive(BoolObjectClosure* is_alive) {
coleenp@4304 386 #ifdef ASSERT
coleenp@4037 387 // The class is alive iff the class loader is alive.
coleenp@4037 388 oop loader = class_loader();
coleenp@4304 389 bool loader_alive = (loader == NULL) || is_alive->do_object_b(loader);
coleenp@4304 390 #endif // ASSERT
coleenp@4304 391
coleenp@4304 392 // The class is alive if it's mirror is alive (which should be marked if the
coleenp@4304 393 // loader is alive) unless it's an anoymous class.
coleenp@4304 394 bool mirror_alive = is_alive->do_object_b(java_mirror());
coleenp@4304 395 assert(!mirror_alive || loader_alive, "loader must be alive if the mirror is"
coleenp@4304 396 " but not the other way around with anonymous classes");
coleenp@4304 397 return mirror_alive;
coleenp@4037 398 }
coleenp@4037 399
stefank@6992 400 void Klass::clean_weak_klass_links(BoolObjectClosure* is_alive, bool clean_alive_klasses) {
coleenp@4037 401 if (!ClassUnloading) {
coleenp@4037 402 return;
coleenp@4037 403 }
coleenp@4037 404
coleenp@4037 405 Klass* root = SystemDictionary::Object_klass();
coleenp@4037 406 Stack<Klass*, mtGC> stack;
coleenp@4037 407
coleenp@4037 408 stack.push(root);
coleenp@4037 409 while (!stack.is_empty()) {
coleenp@4037 410 Klass* current = stack.pop();
coleenp@4037 411
coleenp@4037 412 assert(current->is_loader_alive(is_alive), "just checking, this should be live");
coleenp@4037 413
coleenp@4037 414 // Find and set the first alive subklass
coleenp@4037 415 Klass* sub = current->subklass_oop();
coleenp@4037 416 while (sub != NULL && !sub->is_loader_alive(is_alive)) {
duke@435 417 #ifndef PRODUCT
coleenp@4304 418 if (TraceClassUnloading && WizardMode) {
coleenp@4304 419 ResourceMark rm;
coleenp@4037 420 tty->print_cr("[Unlinking class (subclass) %s]", sub->external_name());
coleenp@4304 421 }
duke@435 422 #endif
coleenp@4037 423 sub = sub->next_sibling_oop();
duke@435 424 }
coleenp@4037 425 current->set_subklass(sub);
coleenp@4037 426 if (sub != NULL) {
coleenp@4037 427 stack.push(sub);
coleenp@4037 428 }
coleenp@4037 429
coleenp@4037 430 // Find and set the first alive sibling
coleenp@4037 431 Klass* sibling = current->next_sibling_oop();
coleenp@4037 432 while (sibling != NULL && !sibling->is_loader_alive(is_alive)) {
coleenp@4304 433 if (TraceClassUnloading && WizardMode) {
coleenp@4304 434 ResourceMark rm;
coleenp@4037 435 tty->print_cr("[Unlinking class (sibling) %s]", sibling->external_name());
coleenp@4304 436 }
coleenp@4037 437 sibling = sibling->next_sibling_oop();
coleenp@4304 438 }
coleenp@4037 439 current->set_next_sibling(sibling);
coleenp@4037 440 if (sibling != NULL) {
coleenp@4037 441 stack.push(sibling);
coleenp@4304 442 }
coleenp@4037 443
coleenp@4037 444 // Clean the implementors list and method data.
stefank@6992 445 if (clean_alive_klasses && current->oop_is_instance()) {
coleenp@4037 446 InstanceKlass* ik = InstanceKlass::cast(current);
coleenp@4037 447 ik->clean_implementors_list(is_alive);
coleenp@4037 448 ik->clean_method_data(is_alive);
duke@435 449 }
duke@435 450 }
duke@435 451 }
duke@435 452
coleenp@4037 453 void Klass::klass_update_barrier_set(oop v) {
coleenp@4037 454 record_modified_oops();
coleenp@4037 455 }
coleenp@4037 456
stefank@6992 457 // This barrier is used by G1 to remember the old oop values, so
stefank@6992 458 // that we don't forget any objects that were live at the snapshot at
stefank@6992 459 // the beginning. This function is only used when we write oops into Klasses.
stefank@6992 460 void Klass::klass_update_barrier_set_pre(oop* p, oop v) {
stefank@6992 461 #if INCLUDE_ALL_GCS
stefank@6992 462 if (UseG1GC) {
stefank@6992 463 oop obj = *p;
stefank@6992 464 if (obj != NULL) {
stefank@6992 465 G1SATBCardTableModRefBS::enqueue(obj);
stefank@6992 466 }
stefank@6992 467 }
stefank@6992 468 #endif
coleenp@4037 469 }
coleenp@4037 470
coleenp@4037 471 void Klass::klass_oop_store(oop* p, oop v) {
coleenp@4037 472 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
coleenp@4037 473 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
coleenp@4037 474
coleenp@4037 475 // do the store
coleenp@4037 476 if (always_do_update_barrier) {
coleenp@4037 477 klass_oop_store((volatile oop*)p, v);
coleenp@4037 478 } else {
stefank@6992 479 klass_update_barrier_set_pre(p, v);
coleenp@4037 480 *p = v;
coleenp@4037 481 klass_update_barrier_set(v);
coleenp@4037 482 }
coleenp@4037 483 }
coleenp@4037 484
coleenp@4037 485 void Klass::klass_oop_store(volatile oop* p, oop v) {
coleenp@4037 486 assert(!Universe::heap()->is_in_reserved((void*)p), "Should store pointer into metadata");
coleenp@4037 487 assert(v == NULL || Universe::heap()->is_in_reserved((void*)v), "Should store pointer to an object");
coleenp@4037 488
stefank@6992 489 klass_update_barrier_set_pre((oop*)p, v); // Cast away volatile.
coleenp@4037 490 OrderAccess::release_store_ptr(p, v);
coleenp@4037 491 klass_update_barrier_set(v);
coleenp@4037 492 }
coleenp@4037 493
coleenp@4037 494 void Klass::oops_do(OopClosure* cl) {
coleenp@4037 495 cl->do_oop(&_java_mirror);
coleenp@4037 496 }
duke@435 497
duke@435 498 void Klass::remove_unshareable_info() {
coleenp@6626 499 assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
coleenp@6626 500
duke@435 501 set_subklass(NULL);
duke@435 502 set_next_sibling(NULL);
coleenp@4037 503 // Clear the java mirror
coleenp@4037 504 set_java_mirror(NULL);
coleenp@4037 505 set_next_link(NULL);
coleenp@4037 506
coleenp@4037 507 // Null out class_loader_data because we don't share that yet.
coleenp@4037 508 set_class_loader_data(NULL);
duke@435 509 }
duke@435 510
coleenp@4037 511 void Klass::restore_unshareable_info(TRAPS) {
mgronlun@6659 512 TRACE_INIT_ID(this);
coleenp@6626 513 // If an exception happened during CDS restore, some of these fields may already be
coleenp@6626 514 // set. We leave the class on the CLD list, even if incomplete so that we don't
coleenp@6626 515 // modify the CLD list outside a safepoint.
coleenp@6626 516 if (class_loader_data() == NULL) {
coleenp@6626 517 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
coleenp@6626 518 // Restore class_loader_data to the null class loader data
coleenp@6626 519 set_class_loader_data(loader_data);
duke@435 520
coleenp@6626 521 // Add to null class loader list first before creating the mirror
coleenp@6626 522 // (same order as class file parsing)
coleenp@6626 523 loader_data->add_class(this);
coleenp@6626 524 }
coleenp@4037 525
coleenp@5176 526 // Recreate the class mirror. The protection_domain is always null for
coleenp@5176 527 // boot loader, for now.
coleenp@6626 528 // Only recreate it if not present. A previous attempt to restore may have
coleenp@6626 529 // gotten an OOM later but keep the mirror if it was created.
coleenp@6626 530 if (java_mirror() == NULL) {
coleenp@6626 531 java_lang_Class::create_mirror(this, Handle(NULL), CHECK);
coleenp@6626 532 }
coleenp@2497 533 }
coleenp@2497 534
coleenp@4037 535 Klass* Klass::array_klass_or_null(int rank) {
duke@435 536 EXCEPTION_MARK;
duke@435 537 // No exception can be thrown by array_klass_impl when called with or_null == true.
duke@435 538 // (In anycase, the execption mark will fail if it do so)
duke@435 539 return array_klass_impl(true, rank, THREAD);
duke@435 540 }
duke@435 541
duke@435 542
coleenp@4037 543 Klass* Klass::array_klass_or_null() {
duke@435 544 EXCEPTION_MARK;
duke@435 545 // No exception can be thrown by array_klass_impl when called with or_null == true.
duke@435 546 // (In anycase, the execption mark will fail if it do so)
duke@435 547 return array_klass_impl(true, THREAD);
duke@435 548 }
duke@435 549
duke@435 550
coleenp@4037 551 Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
coleenp@4142 552 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
duke@435 553 return NULL;
duke@435 554 }
duke@435 555
duke@435 556
coleenp@4037 557 Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
coleenp@4142 558 fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
duke@435 559 return NULL;
duke@435 560 }
duke@435 561
coleenp@4037 562 oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
coleenp@4037 563
duke@435 564 const char* Klass::external_name() const {
jrose@866 565 if (oop_is_instance()) {
coleenp@4037 566 InstanceKlass* ik = (InstanceKlass*) this;
jrose@866 567 if (ik->is_anonymous()) {
twisti@2698 568 assert(EnableInvokeDynamic, "");
coleenp@4304 569 intptr_t hash = 0;
coleenp@4304 570 if (ik->java_mirror() != NULL) {
coleenp@4304 571 // java_mirror might not be created yet, return 0 as hash.
coleenp@4304 572 hash = ik->java_mirror()->identity_hash();
coleenp@4304 573 }
jrose@866 574 char hash_buf[40];
jrose@866 575 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
jrose@866 576 size_t hash_len = strlen(hash_buf);
jrose@866 577
jrose@866 578 size_t result_len = name()->utf8_length();
jrose@866 579 char* result = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
jrose@866 580 name()->as_klass_external_name(result, (int) result_len + 1);
jrose@866 581 assert(strlen(result) == result_len, "");
jrose@866 582 strcpy(result + result_len, hash_buf);
jrose@866 583 assert(strlen(result) == result_len + hash_len, "");
jrose@866 584 return result;
jrose@866 585 }
jrose@866 586 }
jrose@1474 587 if (name() == NULL) return "<unknown>";
duke@435 588 return name()->as_klass_external_name();
duke@435 589 }
duke@435 590
duke@435 591
jrose@1474 592 const char* Klass::signature_name() const {
jrose@1474 593 if (name() == NULL) return "<unknown>";
duke@435 594 return name()->as_C_string();
duke@435 595 }
duke@435 596
duke@435 597 // Unless overridden, modifier_flags is 0.
duke@435 598 jint Klass::compute_modifier_flags(TRAPS) const {
duke@435 599 return 0;
duke@435 600 }
duke@435 601
duke@435 602 int Klass::atomic_incr_biased_lock_revocation_count() {
duke@435 603 return (int) Atomic::add(1, &_biased_lock_revocation_count);
duke@435 604 }
duke@435 605
duke@435 606 // Unless overridden, jvmti_class_status has no flags set.
duke@435 607 jint Klass::jvmti_class_status() const {
duke@435 608 return 0;
duke@435 609 }
duke@435 610
coleenp@4037 611
duke@435 612 // Printing
duke@435 613
coleenp@4037 614 void Klass::print_on(outputStream* st) const {
coleenp@4037 615 ResourceMark rm;
coleenp@4037 616 // print title
coleenp@4037 617 st->print("%s", internal_name());
coleenp@4037 618 print_address_on(st);
coleenp@4037 619 st->cr();
coleenp@4037 620 }
coleenp@4037 621
duke@435 622 void Klass::oop_print_on(oop obj, outputStream* st) {
duke@435 623 ResourceMark rm;
duke@435 624 // print title
duke@435 625 st->print_cr("%s ", internal_name());
duke@435 626 obj->print_address_on(st);
duke@435 627
duke@435 628 if (WizardMode) {
duke@435 629 // print header
duke@435 630 obj->mark()->print_on(st);
duke@435 631 }
duke@435 632
duke@435 633 // print class
duke@435 634 st->print(" - klass: ");
duke@435 635 obj->klass()->print_value_on(st);
duke@435 636 st->cr();
duke@435 637 }
duke@435 638
duke@435 639 void Klass::oop_print_value_on(oop obj, outputStream* st) {
duke@435 640 // print title
duke@435 641 ResourceMark rm; // Cannot print in debug mode without this
duke@435 642 st->print("%s", internal_name());
duke@435 643 obj->print_address_on(st);
duke@435 644 }
duke@435 645
acorn@4497 646 #if INCLUDE_SERVICES
acorn@4497 647 // Size Statistics
acorn@4497 648 void Klass::collect_statistics(KlassSizeStats *sz) const {
acorn@4497 649 sz->_klass_bytes = sz->count(this);
acorn@4497 650 sz->_mirror_bytes = sz->count(java_mirror());
acorn@4497 651 sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
acorn@4497 652
acorn@4497 653 sz->_ro_bytes += sz->_secondary_supers_bytes;
acorn@4497 654 sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
acorn@4497 655 }
acorn@4497 656 #endif // INCLUDE_SERVICES
coleenp@4037 657
duke@435 658 // Verification
duke@435 659
coleenp@6316 660 void Klass::verify_on(outputStream* st) {
coleenp@4037 661
coleenp@5307 662 // This can be expensive, but it is worth checking that this klass is actually
coleenp@5307 663 // in the CLD graph but not in production.
coleenp@6678 664 assert(Metaspace::contains((address)this), "Should be");
coleenp@4037 665
coleenp@4037 666 guarantee(this->is_klass(),"should be klass");
coleenp@4037 667
coleenp@4037 668 if (super() != NULL) {
coleenp@4037 669 guarantee(super()->is_klass(), "should be klass");
coleenp@4037 670 }
coleenp@4037 671 if (secondary_super_cache() != NULL) {
coleenp@4037 672 Klass* ko = secondary_super_cache();
coleenp@4037 673 guarantee(ko->is_klass(), "should be klass");
coleenp@4037 674 }
coleenp@4037 675 for ( uint i = 0; i < primary_super_limit(); i++ ) {
coleenp@4037 676 Klass* ko = _primary_supers[i];
coleenp@4037 677 if (ko != NULL) {
coleenp@4037 678 guarantee(ko->is_klass(), "should be klass");
coleenp@4037 679 }
coleenp@4037 680 }
coleenp@4037 681
coleenp@4037 682 if (java_mirror() != NULL) {
coleenp@4037 683 guarantee(java_mirror()->is_oop(), "should be instance");
coleenp@4037 684 }
coleenp@4037 685 }
coleenp@4037 686
duke@435 687 void Klass::oop_verify_on(oop obj, outputStream* st) {
duke@435 688 guarantee(obj->is_oop(), "should be oop");
duke@435 689 guarantee(obj->klass()->is_klass(), "klass field is not a klass");
duke@435 690 }
duke@435 691
duke@435 692 #ifndef PRODUCT
duke@435 693
drchase@5732 694 bool Klass::verify_vtable_index(int i) {
duke@435 695 if (oop_is_instance()) {
drchase@5732 696 int limit = ((InstanceKlass*)this)->vtable_length()/vtableEntry::size();
drchase@5732 697 assert(i >= 0 && i < limit, err_msg("index %d out of bounds %d", i, limit));
duke@435 698 } else {
coleenp@4037 699 assert(oop_is_array(), "Must be");
drchase@5732 700 int limit = ((ArrayKlass*)this)->vtable_length()/vtableEntry::size();
drchase@5732 701 assert(i >= 0 && i < limit, err_msg("index %d out of bounds %d", i, limit));
duke@435 702 }
drchase@5732 703 return true;
drchase@5732 704 }
drchase@5732 705
drchase@5732 706 bool Klass::verify_itable_index(int i) {
drchase@5732 707 assert(oop_is_instance(), "");
drchase@5732 708 int method_count = klassItable::method_count_for_interface(this);
drchase@5732 709 assert(i >= 0 && i < method_count, "index out of bounds");
drchase@5732 710 return true;
duke@435 711 }
duke@435 712
duke@435 713 #endif
stefank@6976 714
stefank@6976 715 /////////////// Unit tests ///////////////
stefank@6976 716
stefank@6976 717 #ifndef PRODUCT
stefank@6976 718
stefank@6976 719 class TestKlass {
stefank@6976 720 public:
stefank@6976 721 static void test_oop_is_instanceClassLoader() {
stefank@6976 722 assert(SystemDictionary::ClassLoader_klass()->oop_is_instanceClassLoader(), "assert");
stefank@6976 723 assert(!SystemDictionary::String_klass()->oop_is_instanceClassLoader(), "assert");
stefank@6976 724 }
stefank@6976 725 };
stefank@6976 726
stefank@6976 727 void TestKlass_test() {
stefank@6976 728 TestKlass::test_oop_is_instanceClassLoader();
stefank@6976 729 }
stefank@6976 730
stefank@6976 731 #endif

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