1 /* 2 * Copyright (c) 1997, 2023, 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/vmClasses.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, 50 Klass* k, Symbol* name, bool null_free, 51 TRAPS) { 52 assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(), 53 "array klasses must be same size as InstanceKlass"); 54 55 int size = ArrayKlass::static_size(ObjArrayKlass::header_size()); 56 57 return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name, null_free); 58 } 59 60 ObjArrayKlass* ObjArrayKlass::allocate_objArray_klass(ClassLoaderData* loader_data, 61 int n, Klass* element_klass, 62 bool null_free, bool qdesc, TRAPS) { 63 assert(!null_free || (n == 1 && element_klass->is_inline_klass() && qdesc), "null-free unsupported"); 64 65 // Eagerly allocate the direct array supertype. 66 Klass* super_klass = nullptr; 67 if (!Universe::is_bootstrapping() || vmClasses::Object_klass_loaded()) { 68 Klass* element_super = element_klass->super(); 69 if (element_super != nullptr) { 70 // The element type has a direct super. E.g., String[] has direct super of Object[]. 71 if (null_free) { 72 super_klass = element_klass->array_klass_or_null(); 73 } else { 74 super_klass = element_super->array_klass_or_null(); 75 } 76 bool supers_exist = super_klass != nullptr; 77 // Also, see if the element has secondary supertypes. 78 // We need an array type for each. 79 const Array<Klass*>* element_supers = element_klass->secondary_supers(); 80 for( int i = element_supers->length()-1; i >= 0; i-- ) { 81 Klass* elem_super = element_supers->at(i); 82 if (elem_super->array_klass_or_null() == nullptr) { 83 supers_exist = false; 84 break; 85 } 86 } 87 if (null_free) { 88 if (element_klass->array_klass_or_null() == nullptr) { 89 supers_exist = false; 90 } 91 } 92 if (!supers_exist) { 93 // Oops. Not allocated yet. Back out, allocate it, and retry. 94 Klass* ek = nullptr; 95 { 96 MutexUnlocker mu(MultiArray_lock); 97 if (null_free) { 98 element_klass->array_klass(CHECK_NULL); 99 } else { 100 element_super->array_klass(CHECK_NULL); 101 } 102 for( int i = element_supers->length()-1; i >= 0; i-- ) { 103 Klass* elem_super = element_supers->at(i); 104 elem_super->array_klass(CHECK_NULL); 105 } 106 // Now retry from the beginning 107 if (null_free) { 108 ek = InlineKlass::cast(element_klass)->value_array_klass(CHECK_NULL); 109 } else { 110 ek = element_klass->array_klass(n, CHECK_NULL); 111 } 112 } // re-lock 113 return ObjArrayKlass::cast(ek); 114 } 115 } else { 116 // The element type is already Object. Object[] has direct super of Object. 117 super_klass = vmClasses::Object_klass(); 118 } 119 } 120 121 // Create type name for klass. 122 Symbol* name = ArrayKlass::create_element_klass_array_name(element_klass, qdesc, CHECK_NULL); 123 124 // Initialize instance variables 125 ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, null_free, CHECK_NULL); 126 127 ModuleEntry* module = oak->module(); 128 assert(module != nullptr, "No module entry for array"); 129 130 // Call complete_create_array_klass after all instance variables has been initialized. 131 ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_NULL); 132 133 // Add all classes to our internal class loader list here, 134 // including classes in the bootstrap (null) class loader. 135 // Do this step after creating the mirror so that if the 136 // mirror creation fails, loaded_classes_do() doesn't find 137 // an array class without a mirror. 138 loader_data->add_class(oak); 139 140 return oak; 141 } 142 143 ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name, bool null_free) : ArrayKlass(name, Kind) { 144 set_dimension(n); 145 set_element_klass(element_klass); 146 147 assert(!null_free || name->is_Q_array_signature(), "sanity check"); 148 149 Klass* bk; 150 if (element_klass->is_objArray_klass()) { 151 bk = ObjArrayKlass::cast(element_klass)->bottom_klass(); 152 } else if (element_klass->is_flatArray_klass()) { 153 bk = FlatArrayKlass::cast(element_klass)->element_klass(); 154 } else { 155 bk = element_klass; 156 } 157 assert(bk != nullptr && (bk->is_instance_klass() || bk->is_typeArray_klass()), "invalid bottom klass"); 158 set_bottom_klass(bk); 159 set_class_loader_data(bk->class_loader_data()); 160 161 int lh = array_layout_helper(T_OBJECT); 162 if (null_free) { 163 assert(n == 1, "Bytecode does not support null-free multi-dim"); 164 lh = layout_helper_set_null_free(lh); 165 #ifdef _LP64 166 set_prototype_header(markWord::null_free_array_prototype()); 167 assert(prototype_header().is_null_free_array(), "sanity"); 168 #else 169 set_prototype_header(markWord::inline_type_prototype()); 170 #endif 171 } 172 set_layout_helper(lh); 173 assert(is_array_klass(), "sanity"); 174 assert(is_objArray_klass(), "sanity"); 175 } 176 177 size_t ObjArrayKlass::oop_size(oop obj) const { 178 assert(obj->is_objArray(), "must be object array"); 179 return objArrayOop(obj)->object_size(); 180 } 181 182 objArrayOop ObjArrayKlass::allocate(int length, TRAPS) { 183 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 184 size_t size = objArrayOopDesc::object_size(length); 185 bool populate_null_free = is_null_free_array_klass(); 186 objArrayOop array = (objArrayOop)Universe::heap()->array_allocate(this, size, length, 187 /* do_zero */ true, CHECK_NULL); 188 objArrayHandle array_h(THREAD, array); 189 if (populate_null_free) { 190 assert(dimension() == 1, "Can only populate the final dimension"); 191 assert(element_klass()->is_inline_klass(), "Unexpected"); 192 assert(!element_klass()->is_array_klass(), "ArrayKlass unexpected here"); 193 assert(!InlineKlass::cast(element_klass())->flatten_array(), "Expected flatArrayOop allocation"); 194 element_klass()->initialize(CHECK_NULL); 195 // Populate default values... 196 instanceOop value = (instanceOop) InlineKlass::cast(element_klass())->default_value(); 197 for (int i = 0; i < length; i++) { 198 array_h->obj_at_put(i, value); 199 } 200 } 201 return array_h(); 202 } 203 204 oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) { 205 int length = *sizes; 206 if (rank == 1) { // last dim may be flatArray, check if we have any special storage requirements 207 if (name()->char_at(1) != JVM_SIGNATURE_ARRAY && name()->is_Q_array_signature()) { 208 return oopFactory::new_valueArray(element_klass(), length, CHECK_NULL); 209 } else { 210 return oopFactory::new_objArray(element_klass(), length, CHECK_NULL); 211 } 212 } 213 guarantee(rank > 1, "Rank below 1"); 214 // Call to lower_dimension uses this pointer, so most be called before a 215 // possible GC 216 Klass* ld_klass = lower_dimension(); 217 // If length < 0 allocate will throw an exception. 218 objArrayOop array = allocate(length, CHECK_NULL); 219 objArrayHandle h_array (THREAD, array); 220 if (length != 0) { 221 for (int index = 0; index < length; index++) { 222 ArrayKlass* ak = ArrayKlass::cast(ld_klass); 223 oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL); 224 h_array->obj_at_put(index, sub_array); 225 } 226 } else { 227 // Since this array dimension has zero length, nothing will be 228 // allocated, however the lower dimension values must be checked 229 // for illegal values. 230 for (int i = 0; i < rank - 1; ++i) { 231 sizes += 1; 232 if (*sizes < 0) { 233 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", *sizes)); 234 } 235 } 236 } 237 return h_array(); 238 } 239 240 // Either oop or narrowOop depending on UseCompressedOops. 241 void ObjArrayKlass::do_copy(arrayOop s, size_t src_offset, 242 arrayOop d, size_t dst_offset, int length, TRAPS) { 243 if (s == d) { 244 // since source and destination are equal we do not need conversion checks. 245 assert(length > 0, "sanity check"); 246 ArrayAccess<>::oop_arraycopy(s, src_offset, d, dst_offset, length); 247 } else { 248 // We have to make sure all elements conform to the destination array 249 Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass(); 250 Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass(); 251 // Perform null check if dst is null-free but src has no such guarantee 252 bool null_check = ((!s->klass()->is_null_free_array_klass()) && 253 d->klass()->is_null_free_array_klass()); 254 if (stype == bound || stype->is_subtype_of(bound)) { 255 if (null_check) { 256 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_NOTNULL>::oop_arraycopy(s, src_offset, d, dst_offset, length); 257 } else { 258 ArrayAccess<ARRAYCOPY_DISJOINT>::oop_arraycopy(s, src_offset, d, dst_offset, length); 259 } 260 } else { 261 if (null_check) { 262 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST | ARRAYCOPY_NOTNULL>::oop_arraycopy(s, src_offset, d, dst_offset, length); 263 } else { 264 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST>::oop_arraycopy(s, src_offset, d, dst_offset, length); 265 } 266 } 267 } 268 } 269 270 void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d, 271 int dst_pos, int length, TRAPS) { 272 assert(s->is_objArray(), "must be obj array"); 273 274 if (UseFlatArray) { 275 if (d->is_flatArray()) { 276 FlatArrayKlass::cast(d->klass())->copy_array(s, src_pos, d, dst_pos, length, THREAD); 277 return; 278 } 279 } 280 281 if (!d->is_objArray()) { 282 ResourceMark rm(THREAD); 283 stringStream ss; 284 if (d->is_typeArray()) { 285 ss.print("arraycopy: type mismatch: can not copy object array[] into %s[]", 286 type2name_tab[ArrayKlass::cast(d->klass())->element_type()]); 287 } else { 288 ss.print("arraycopy: destination type %s is not an array", d->klass()->external_name()); 289 } 290 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string()); 291 } 292 293 // Check is all offsets and lengths are non negative 294 if (src_pos < 0 || dst_pos < 0 || length < 0) { 295 // Pass specific exception reason. 296 ResourceMark rm(THREAD); 297 stringStream ss; 298 if (src_pos < 0) { 299 ss.print("arraycopy: source index %d out of bounds for object array[%d]", 300 src_pos, s->length()); 301 } else if (dst_pos < 0) { 302 ss.print("arraycopy: destination index %d out of bounds for object array[%d]", 303 dst_pos, d->length()); 304 } else { 305 ss.print("arraycopy: length %d is negative", length); 306 } 307 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 308 } 309 // Check if the ranges are valid 310 if ((((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) || 311 (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length())) { 312 // Pass specific exception reason. 313 ResourceMark rm(THREAD); 314 stringStream ss; 315 if (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) { 316 ss.print("arraycopy: last source index %u out of bounds for object array[%d]", 317 (unsigned int) length + (unsigned int) src_pos, s->length()); 318 } else { 319 ss.print("arraycopy: last destination index %u out of bounds for object array[%d]", 320 (unsigned int) length + (unsigned int) dst_pos, d->length()); 321 } 322 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 323 } 324 325 // Special case. Boundary cases must be checked first 326 // This allows the following call: copy_array(s, s.length(), d.length(), 0). 327 // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(), 328 // points to the right of the last element. 329 if (length==0) { 330 return; 331 } 332 if (UseCompressedOops) { 333 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(src_pos); 334 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(dst_pos); 335 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(s, src_offset, nullptr) == 336 objArrayOop(s)->obj_at_addr<narrowOop>(src_pos), "sanity"); 337 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(d, dst_offset, nullptr) == 338 objArrayOop(d)->obj_at_addr<narrowOop>(dst_pos), "sanity"); 339 do_copy(s, src_offset, d, dst_offset, length, CHECK); 340 } else { 341 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(src_pos); 342 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(dst_pos); 343 assert(arrayOopDesc::obj_offset_to_raw<oop>(s, src_offset, nullptr) == 344 objArrayOop(s)->obj_at_addr<oop>(src_pos), "sanity"); 345 assert(arrayOopDesc::obj_offset_to_raw<oop>(d, dst_offset, nullptr) == 346 objArrayOop(d)->obj_at_addr<oop>(dst_pos), "sanity"); 347 do_copy(s, src_offset, d, dst_offset, length, CHECK); 348 } 349 } 350 351 352 Klass* ObjArrayKlass::array_klass(int n, TRAPS) { 353 assert(dimension() <= n, "check order of chain"); 354 int dim = dimension(); 355 if (dim == n) return this; 356 357 // lock-free read needs acquire semantics 358 if (higher_dimension_acquire() == nullptr) { 359 360 ResourceMark rm(THREAD); 361 { 362 // Ensure atomic creation of higher dimensions 363 MutexLocker mu(THREAD, MultiArray_lock); 364 365 // Check if another thread beat us 366 if (higher_dimension() == nullptr) { 367 368 // Create multi-dim klass object and link them together 369 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, 370 false, this->name()->is_Q_array_signature(), CHECK_NULL); 371 ObjArrayKlass* ak = ObjArrayKlass::cast(k); 372 ak->set_lower_dimension(this); 373 // use 'release' to pair with lock-free load 374 release_set_higher_dimension(ak); 375 assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass"); 376 } 377 } 378 } 379 380 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); 381 THREAD->check_possible_safepoint(); 382 return ak->array_klass(n, THREAD); 383 } 384 385 Klass* ObjArrayKlass::array_klass_or_null(int n) { 386 387 assert(dimension() <= n, "check order of chain"); 388 int dim = dimension(); 389 if (dim == n) return this; 390 391 // lock-free read needs acquire semantics 392 if (higher_dimension_acquire() == nullptr) { 393 return nullptr; 394 } 395 396 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); 397 return ak->array_klass_or_null(n); 398 } 399 400 Klass* ObjArrayKlass::array_klass(TRAPS) { 401 return array_klass(dimension() + 1, THREAD); 402 } 403 404 Klass* ObjArrayKlass::array_klass_or_null() { 405 return array_klass_or_null(dimension() + 1); 406 } 407 408 bool ObjArrayKlass::can_be_primary_super_slow() const { 409 if (!bottom_klass()->can_be_primary_super()) 410 // array of interfaces 411 return false; 412 else 413 return Klass::can_be_primary_super_slow(); 414 } 415 416 GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots, 417 Array<InstanceKlass*>* transitive_interfaces) { 418 assert(transitive_interfaces == nullptr, "sanity"); 419 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... }; 420 const Array<Klass*>* elem_supers = element_klass()->secondary_supers(); 421 int num_elem_supers = elem_supers == nullptr ? 0 : elem_supers->length(); 422 int num_secondaries = num_extra_slots + 2 + num_elem_supers; 423 if (num_secondaries == 2) { 424 // Must share this for correct bootstrapping! 425 set_secondary_supers(Universe::the_array_interfaces_array()); 426 return nullptr; 427 } else { 428 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2); 429 secondaries->push(vmClasses::Cloneable_klass()); 430 secondaries->push(vmClasses::Serializable_klass()); 431 for (int i = 0; i < num_elem_supers; i++) { 432 Klass* elem_super = elem_supers->at(i); 433 Klass* array_super = elem_super->array_klass_or_null(); 434 assert(array_super != nullptr, "must already have been created"); 435 secondaries->push(array_super); 436 } 437 return secondaries; 438 } 439 } 440 441 void ObjArrayKlass::initialize(TRAPS) { 442 bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass 443 } 444 445 void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) { 446 ArrayKlass::metaspace_pointers_do(it); 447 it->push(&_element_klass); 448 it->push(&_bottom_klass); 449 } 450 451 jint ObjArrayKlass::compute_modifier_flags() const { 452 // The modifier for an objectArray is the same as its element 453 if (element_klass() == nullptr) { 454 assert(Universe::is_bootstrapping(), "partial objArray only at startup"); 455 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC; 456 } 457 // Return the flags of the bottom element type. 458 jint element_flags = bottom_klass()->compute_modifier_flags(); 459 460 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) 461 | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL); 462 } 463 464 ModuleEntry* ObjArrayKlass::module() const { 465 assert(bottom_klass() != nullptr, "ObjArrayKlass returned unexpected null bottom_klass"); 466 // The array is defined in the module of its bottom class 467 return bottom_klass()->module(); 468 } 469 470 PackageEntry* ObjArrayKlass::package() const { 471 assert(bottom_klass() != nullptr, "ObjArrayKlass returned unexpected null bottom_klass"); 472 return bottom_klass()->package(); 473 } 474 475 // Printing 476 477 void ObjArrayKlass::print_on(outputStream* st) const { 478 #ifndef PRODUCT 479 Klass::print_on(st); 480 st->print(" - element klass: "); 481 element_klass()->print_value_on(st); 482 st->cr(); 483 #endif //PRODUCT 484 } 485 486 void ObjArrayKlass::print_value_on(outputStream* st) const { 487 assert(is_klass(), "must be klass"); 488 489 element_klass()->print_value_on(st); 490 st->print("[]"); 491 } 492 493 #ifndef PRODUCT 494 495 void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) { 496 ArrayKlass::oop_print_on(obj, st); 497 assert(obj->is_objArray(), "must be objArray"); 498 objArrayOop oa = objArrayOop(obj); 499 int print_len = MIN2((intx) oa->length(), MaxElementPrintSize); 500 for(int index = 0; index < print_len; index++) { 501 st->print(" - %3d : ", index); 502 if (oa->obj_at(index) != nullptr) { 503 oa->obj_at(index)->print_value_on(st); 504 st->cr(); 505 } else { 506 st->print_cr("null"); 507 } 508 } 509 int remaining = oa->length() - print_len; 510 if (remaining > 0) { 511 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining); 512 } 513 } 514 515 #endif //PRODUCT 516 517 void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) { 518 assert(obj->is_objArray(), "must be objArray"); 519 st->print("a "); 520 element_klass()->print_value_on(st); 521 int len = objArrayOop(obj)->length(); 522 st->print("[%d] ", len); 523 if (obj != nullptr) { 524 obj->print_address_on(st); 525 } else { 526 st->print_cr("null"); 527 } 528 } 529 530 const char* ObjArrayKlass::internal_name() const { 531 return external_name(); 532 } 533 534 535 // Verification 536 537 void ObjArrayKlass::verify_on(outputStream* st) { 538 ArrayKlass::verify_on(st); 539 guarantee(element_klass()->is_klass(), "should be klass"); 540 guarantee(bottom_klass()->is_klass(), "should be klass"); 541 Klass* bk = bottom_klass(); 542 guarantee(bk->is_instance_klass() || bk->is_typeArray_klass() || bk->is_flatArray_klass(), 543 "invalid bottom klass"); 544 } 545 546 void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) { 547 ArrayKlass::oop_verify_on(obj, st); 548 guarantee(obj->is_objArray(), "must be objArray"); 549 guarantee(obj->is_null_free_array() || (!is_null_free_array_klass()), "null-free klass but not object"); 550 objArrayOop oa = objArrayOop(obj); 551 for(int index = 0; index < oa->length(); index++) { 552 guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop"); 553 } 554 }