1 /* 2 * Copyright (c) 1997, 2019, 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/moduleEntry.hpp" 27 #include "classfile/packageEntry.hpp" 28 #include "classfile/symbolTable.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "gc/shared/collectedHeap.inline.hpp" 32 #include "memory/iterator.inline.hpp" 33 #include "memory/metadataFactory.hpp" 34 #include "memory/metaspaceClosure.hpp" 35 #include "memory/oopFactory.hpp" 36 #include "memory/resourceArea.hpp" 37 #include "memory/universe.hpp" 38 #include "oops/arrayKlass.inline.hpp" 39 #include "oops/instanceKlass.hpp" 40 #include "oops/klass.inline.hpp" 41 #include "oops/objArrayKlass.inline.hpp" 42 #include "oops/objArrayOop.inline.hpp" 43 #include "oops/oop.inline.hpp" 44 #include "oops/symbol.hpp" 45 #include "runtime/handles.inline.hpp" 46 #include "runtime/mutexLocker.hpp" 47 #include "utilities/macros.hpp" 48 49 ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS) { 50 assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(), 51 "array klasses must be same size as InstanceKlass"); 52 53 int size = ArrayKlass::static_size(ObjArrayKlass::header_size()); 54 55 return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name); 56 } 57 58 Klass* ObjArrayKlass::allocate_objArray_klass(ArrayStorageProperties storage_props, 59 int n, Klass* element_klass, TRAPS) { 60 // Eagerly allocate the direct array supertype. 61 Klass* super_klass = NULL; 62 if (!Universe::is_bootstrapping() || SystemDictionary::Object_klass_loaded()) { 63 Klass* element_super = element_klass->super(); 64 if (element_super != NULL) { 65 // The element type has a direct super. E.g., String[] has direct super of Object[]. 66 super_klass = element_super->array_klass_or_null(storage_props); 67 bool supers_exist = super_klass != NULL; 68 // Also, see if the element has secondary supertypes. 69 // We need an array type for each. 70 const Array<Klass*>* element_supers = element_klass->secondary_supers(); 71 for( int i = element_supers->length()-1; i >= 0; i-- ) { 72 Klass* elem_super = element_supers->at(i); 73 if (elem_super->array_klass_or_null(ArrayStorageProperties::empty) == NULL) { 74 supers_exist = false; 75 break; 76 } 77 } 78 if (!supers_exist) { 79 // Oops. Not allocated yet. Back out, allocate it, and retry. 80 Klass* ek = NULL; 81 { 82 MutexUnlocker mu(MultiArray_lock); 83 super_klass = element_super->array_klass(CHECK_0); 84 for( int i = element_supers->length()-1; i >= 0; i-- ) { 85 Klass* elem_super = element_supers->at(i); 86 elem_super->array_klass(CHECK_0); 87 } 88 // Now retry from the beginning 89 ek = element_klass->array_klass(storage_props, n, CHECK_0); 90 } // re-lock 91 return ek; 92 } 93 } else { 94 // The element type is already Object. Object[] has direct super of Object. 95 super_klass = SystemDictionary::Object_klass(); 96 } 97 } 98 99 // Create type name for klass. 100 Symbol* name = ArrayKlass::create_element_klass_array_name(storage_props.is_null_free(), element_klass, CHECK_NULL); 101 102 // Initialize instance variables 103 ClassLoaderData* loader_data = element_klass->class_loader_data(); 104 ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, CHECK_0); 105 106 // Add all classes to our internal class loader list here, 107 // including classes in the bootstrap (NULL) class loader. 108 // GC walks these as strong roots. 109 loader_data->add_class(oak); 110 111 ModuleEntry* module = oak->module(); 112 assert(module != NULL, "No module entry for array"); 113 114 // Call complete_create_array_klass after all instance variables has been initialized. 115 ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_0); 116 117 return oak; 118 } 119 120 ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name) : ArrayKlass(name, ID) { 121 this->set_dimension(n); 122 this->set_element_klass(element_klass); 123 // decrement refcount because object arrays are not explicitly freed. The 124 // InstanceKlass array_name() keeps the name counted while the klass is 125 // loaded. 126 name->decrement_refcount(); 127 128 Klass* bk; 129 if (element_klass->is_objArray_klass()) { 130 bk = ObjArrayKlass::cast(element_klass)->bottom_klass(); 131 } else if (element_klass->is_valueArray_klass()) { 132 bk = ValueArrayKlass::cast(element_klass)->element_klass(); 133 } else { 134 bk = element_klass; 135 } 136 assert(bk != NULL && (bk->is_instance_klass() 137 || bk->is_typeArray_klass()), "invalid bottom klass"); 138 this->set_bottom_klass(bk); 139 this->set_class_loader_data(bk->class_loader_data()); 140 141 this->set_layout_helper(array_layout_helper(T_OBJECT)); 142 assert(this->is_array_klass(), "sanity"); 143 assert(this->is_objArray_klass(), "sanity"); 144 } 145 146 int ObjArrayKlass::oop_size(oop obj) const { 147 assert(obj->is_objArray(), "must be object array"); 148 return objArrayOop(obj)->object_size(); 149 } 150 151 objArrayOop ObjArrayKlass::allocate(int length, TRAPS) { 152 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_0); 153 int size = objArrayOopDesc::object_size(length); 154 bool populate_null_free = storage_properties().is_null_free() && (dimension() == 1); 155 objArrayOop array = (objArrayOop)Universe::heap()->array_allocate(this, size, length, 156 /* do_zero */ true, THREAD); 157 if (populate_null_free) { 158 assert(!element_klass()->is_array_klass(), "ArrayKlass unexpected here"); 159 // Populate default values... 160 objArrayHandle array_h(THREAD, array); 161 instanceOop value = (instanceOop) ValueKlass::cast(element_klass())->default_value(); 162 for (int i = 0; i < length; i++) { 163 array_h->obj_at_put(i, value); 164 } 165 } 166 return array; 167 } 168 169 static int multi_alloc_counter = 0; 170 171 oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) { 172 int length = *sizes; 173 if (rank == 1) { // last dim may be valueArray, check if we have any special storage requirements 174 if ((!element_klass()->is_array_klass()) && storage_properties().is_null_free()) { 175 return oopFactory::new_valueArray(element_klass(), length, CHECK_NULL); 176 } else { 177 return oopFactory::new_objArray(element_klass(), length, CHECK_NULL); 178 } 179 } 180 guarantee(rank > 1, "Rank below 1"); 181 // Call to lower_dimension uses this pointer, so most be called before a 182 // possible GC 183 Klass* ld_klass = lower_dimension(); 184 // If length < 0 allocate will throw an exception. 185 objArrayOop array = allocate(length, CHECK_NULL); 186 objArrayHandle h_array (THREAD, array); 187 if (length != 0) { 188 for (int index = 0; index < length; index++) { 189 ArrayKlass* ak = ArrayKlass::cast(ld_klass); 190 oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL); 191 h_array->obj_at_put(index, sub_array); 192 } 193 } else { 194 // Since this array dimension has zero length, nothing will be 195 // allocated, however the lower dimension values must be checked 196 // for illegal values. 197 for (int i = 0; i < rank - 1; ++i) { 198 sizes += 1; 199 if (*sizes < 0) { 200 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", *sizes)); 201 } 202 } 203 } 204 return h_array(); 205 } 206 207 ArrayStorageProperties ObjArrayKlass::storage_properties() { 208 return name()->is_Q_array_signature() ? ArrayStorageProperties::null_free : ArrayStorageProperties::empty; 209 } 210 211 // Either oop or narrowOop depending on UseCompressedOops. 212 void ObjArrayKlass::do_copy(arrayOop s, size_t src_offset, 213 arrayOop d, size_t dst_offset, int length, TRAPS) { 214 if (oopDesc::equals(s, d)) { 215 // since source and destination are equal we do not need conversion checks. 216 assert(length > 0, "sanity check"); 217 ArrayAccess<>::oop_arraycopy(s, src_offset, d, dst_offset, length); 218 } else { 219 // We have to make sure all elements conform to the destination array 220 Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass(); 221 Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass(); 222 if (stype == bound || stype->is_subtype_of(bound)) { 223 // elements are guaranteed to be subtypes, so no check necessary 224 ArrayAccess<ARRAYCOPY_DISJOINT>::oop_arraycopy(s, src_offset, d, dst_offset, length); 225 } else { 226 // slow case: need individual subtype checks 227 // note: don't use obj_at_put below because it includes a redundant store check 228 if (!ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST>::oop_arraycopy(s, src_offset, d, dst_offset, length)) { 229 ResourceMark rm(THREAD); 230 stringStream ss; 231 if (!bound->is_subtype_of(stype)) { 232 ss.print("arraycopy: type mismatch: can not copy %s[] into %s[]", 233 stype->external_name(), bound->external_name()); 234 } else { 235 // oop_arraycopy should return the index in the source array that 236 // contains the problematic oop. 237 ss.print("arraycopy: element type mismatch: can not cast one of the elements" 238 " of %s[] to the type of the destination array, %s", 239 stype->external_name(), bound->external_name()); 240 } 241 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string()); 242 } 243 } 244 } 245 } 246 247 void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d, 248 int dst_pos, int length, TRAPS) { 249 assert(s->is_objArray(), "must be obj array"); 250 251 if (EnableValhalla) { 252 if (d->is_valueArray()) { 253 ValueArrayKlass::cast(d->klass())->copy_array(s, src_pos, d, dst_pos, length, THREAD); 254 return; 255 } 256 } 257 258 if (!d->is_objArray()) { 259 ResourceMark rm(THREAD); 260 stringStream ss; 261 if (d->is_typeArray()) { 262 ss.print("arraycopy: type mismatch: can not copy object array[] into %s[]", 263 type2name_tab[ArrayKlass::cast(d->klass())->element_type()]); 264 } else { 265 ss.print("arraycopy: destination type %s is not an array", d->klass()->external_name()); 266 } 267 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string()); 268 } 269 270 // Check is all offsets and lengths are non negative 271 if (src_pos < 0 || dst_pos < 0 || length < 0) { 272 // Pass specific exception reason. 273 ResourceMark rm(THREAD); 274 stringStream ss; 275 if (src_pos < 0) { 276 ss.print("arraycopy: source index %d out of bounds for object array[%d]", 277 src_pos, s->length()); 278 } else if (dst_pos < 0) { 279 ss.print("arraycopy: destination index %d out of bounds for object array[%d]", 280 dst_pos, d->length()); 281 } else { 282 ss.print("arraycopy: length %d is negative", length); 283 } 284 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 285 } 286 // Check if the ranges are valid 287 if ((((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) || 288 (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length())) { 289 // Pass specific exception reason. 290 ResourceMark rm(THREAD); 291 stringStream ss; 292 if (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) { 293 ss.print("arraycopy: last source index %u out of bounds for object array[%d]", 294 (unsigned int) length + (unsigned int) src_pos, s->length()); 295 } else { 296 ss.print("arraycopy: last destination index %u out of bounds for object array[%d]", 297 (unsigned int) length + (unsigned int) dst_pos, d->length()); 298 } 299 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 300 } 301 302 // Special case. Boundary cases must be checked first 303 // This allows the following call: copy_array(s, s.length(), d.length(), 0). 304 // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(), 305 // points to the right of the last element. 306 if (length==0) { 307 return; 308 } 309 if (EnableValhalla && ArrayKlass::cast(d->klass())->element_klass()->is_value()) { 310 assert(d->is_objArray(), "Expected objArray"); 311 ValueKlass* d_elem_vklass = ValueKlass::cast(ArrayKlass::cast(d->klass())->element_klass()); 312 objArrayOop da = objArrayOop(d); 313 objArrayOop sa = objArrayOop(s); 314 int src_end = src_pos + length; 315 while (src_pos < src_end) { 316 oop se = sa->obj_at(src_pos); 317 if (se == NULL) { 318 THROW(vmSymbols::java_lang_NullPointerException()); 319 } 320 // Check exact type per element 321 if (se->klass() != d_elem_vklass) { 322 THROW(vmSymbols::java_lang_ArrayStoreException()); 323 } 324 da->obj_at_put(dst_pos, se); // TODO: review with ValueArrayKlass::copy_array and Access API 325 dst_pos++; 326 src_pos++; 327 } 328 } else if (UseCompressedOops) { 329 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(src_pos); 330 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(dst_pos); 331 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(s, src_offset, NULL) == 332 objArrayOop(s)->obj_at_addr_raw<narrowOop>(src_pos), "sanity"); 333 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(d, dst_offset, NULL) == 334 objArrayOop(d)->obj_at_addr_raw<narrowOop>(dst_pos), "sanity"); 335 do_copy(s, src_offset, d, dst_offset, length, CHECK); 336 } else { 337 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(src_pos); 338 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(dst_pos); 339 assert(arrayOopDesc::obj_offset_to_raw<oop>(s, src_offset, NULL) == 340 objArrayOop(s)->obj_at_addr_raw<oop>(src_pos), "sanity"); 341 assert(arrayOopDesc::obj_offset_to_raw<oop>(d, dst_offset, NULL) == 342 objArrayOop(d)->obj_at_addr_raw<oop>(dst_pos), "sanity"); 343 do_copy(s, src_offset, d, dst_offset, length, CHECK); 344 } 345 } 346 347 348 Klass* ObjArrayKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, int n, TRAPS) { 349 assert(!storage_props.is_flattened() || n > 1, "Cannot flatten"); 350 assert(dimension() <= n, "check order of chain"); 351 int dim = dimension(); 352 if (dim == n) return this; 353 354 // lock-free read needs acquire semantics 355 if (higher_dimension_acquire() == NULL) { 356 if (or_null) return NULL; 357 358 ResourceMark rm; 359 JavaThread *jt = (JavaThread *)THREAD; 360 { 361 // Ensure atomic creation of higher dimensions 362 MutexLocker mu(MultiArray_lock, THREAD); 363 364 // Check if another thread beat us 365 if (higher_dimension() == NULL) { 366 367 // Create multi-dim klass object and link them together 368 Klass* k = 369 ObjArrayKlass::allocate_objArray_klass(storage_props, dim + 1, this, CHECK_NULL); 370 ObjArrayKlass* ak = ObjArrayKlass::cast(k); 371 ak->set_lower_dimension(this); 372 // use 'release' to pair with lock-free load 373 release_set_higher_dimension(ak); 374 assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass"); 375 } 376 } 377 } else { 378 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 379 } 380 381 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); 382 if (or_null) { 383 return ak->array_klass_or_null(storage_props, n); 384 } 385 return ak->array_klass(storage_props, n, THREAD); 386 } 387 388 Klass* ObjArrayKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, TRAPS) { 389 return array_klass_impl(storage_props, or_null, dimension() + 1, THREAD); 390 } 391 392 bool ObjArrayKlass::can_be_primary_super_slow() const { 393 if (!bottom_klass()->can_be_primary_super()) 394 // array of interfaces 395 return false; 396 else 397 return Klass::can_be_primary_super_slow(); 398 } 399 400 GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots, 401 Array<InstanceKlass*>* transitive_interfaces) { 402 assert(transitive_interfaces == NULL, "sanity"); 403 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... }; 404 const Array<Klass*>* elem_supers = element_klass()->secondary_supers(); 405 int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length(); 406 int num_secondaries = num_extra_slots + 2 + num_elem_supers; 407 if (num_secondaries == 2) { 408 // Must share this for correct bootstrapping! 409 set_secondary_supers(Universe::the_array_interfaces_array()); 410 return NULL; 411 } else { 412 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2); 413 secondaries->push(SystemDictionary::Cloneable_klass()); 414 secondaries->push(SystemDictionary::Serializable_klass()); 415 for (int i = 0; i < num_elem_supers; i++) { 416 Klass* elem_super = elem_supers->at(i); 417 Klass* array_super = elem_super->array_klass_or_null(ArrayStorageProperties::empty); 418 assert(array_super != NULL, "must already have been created"); 419 secondaries->push(array_super); 420 } 421 return secondaries; 422 } 423 } 424 425 void ObjArrayKlass::initialize(TRAPS) { 426 bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass 427 } 428 429 void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) { 430 ArrayKlass::metaspace_pointers_do(it); 431 it->push(&_element_klass); 432 it->push(&_bottom_klass); 433 } 434 435 // JVM support 436 437 jint ObjArrayKlass::compute_modifier_flags(TRAPS) const { 438 // The modifier for an objectArray is the same as its element 439 if (element_klass() == NULL) { 440 assert(Universe::is_bootstrapping(), "partial objArray only at startup"); 441 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC; 442 } 443 // Return the flags of the bottom element type. 444 jint element_flags = bottom_klass()->compute_modifier_flags(CHECK_0); 445 446 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) 447 | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL); 448 } 449 450 ModuleEntry* ObjArrayKlass::module() const { 451 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); 452 // The array is defined in the module of its bottom class 453 return bottom_klass()->module(); 454 } 455 456 PackageEntry* ObjArrayKlass::package() const { 457 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); 458 return bottom_klass()->package(); 459 } 460 461 // Printing 462 463 void ObjArrayKlass::print_on(outputStream* st) const { 464 #ifndef PRODUCT 465 Klass::print_on(st); 466 st->print(" - element klass: "); 467 element_klass()->print_value_on(st); 468 st->cr(); 469 #endif //PRODUCT 470 } 471 472 void ObjArrayKlass::print_value_on(outputStream* st) const { 473 assert(is_klass(), "must be klass"); 474 475 element_klass()->print_value_on(st); 476 st->print("[]"); 477 } 478 479 #ifndef PRODUCT 480 481 void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) { 482 ArrayKlass::oop_print_on(obj, st); 483 assert(obj->is_objArray(), "must be objArray"); 484 objArrayOop oa = objArrayOop(obj); 485 int print_len = MIN2((intx) oa->length(), MaxElementPrintSize); 486 for(int index = 0; index < print_len; index++) { 487 st->print(" - %3d : ", index); 488 if (oa->obj_at(index) != NULL) { 489 oa->obj_at(index)->print_value_on(st); 490 st->cr(); 491 } else { 492 st->print_cr("NULL"); 493 } 494 } 495 int remaining = oa->length() - print_len; 496 if (remaining > 0) { 497 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining); 498 } 499 } 500 501 #endif //PRODUCT 502 503 void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) { 504 assert(obj->is_objArray(), "must be objArray"); 505 st->print("a "); 506 element_klass()->print_value_on(st); 507 int len = objArrayOop(obj)->length(); 508 st->print("[%d] ", len); 509 if (obj != NULL) { 510 obj->print_address_on(st); 511 } else { 512 st->print_cr("NULL"); 513 } 514 } 515 516 const char* ObjArrayKlass::internal_name() const { 517 return external_name(); 518 } 519 520 521 // Verification 522 523 void ObjArrayKlass::verify_on(outputStream* st) { 524 ArrayKlass::verify_on(st); 525 guarantee(element_klass()->is_klass(), "should be klass"); 526 guarantee(bottom_klass()->is_klass(), "should be klass"); 527 Klass* bk = bottom_klass(); 528 guarantee(bk->is_instance_klass() || bk->is_typeArray_klass() || bk->is_valueArray_klass(), 529 "invalid bottom klass"); 530 } 531 532 void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) { 533 ArrayKlass::oop_verify_on(obj, st); 534 guarantee(obj->is_objArray(), "must be objArray"); 535 objArrayOop oa = objArrayOop(obj); 536 for(int index = 0; index < oa->length(); index++) { 537 guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop"); 538 } 539 }