1 /* 2 * Copyright (c) 1997, 2021, 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/resourceArea.hpp" 36 #include "memory/universe.hpp" 37 #include "oops/arrayKlass.inline.hpp" 38 #include "oops/instanceKlass.hpp" 39 #include "oops/klass.inline.hpp" 40 #include "oops/objArrayKlass.inline.hpp" 41 #include "oops/objArrayOop.inline.hpp" 42 #include "oops/oop.inline.hpp" 43 #include "oops/symbol.hpp" 44 #include "runtime/handles.inline.hpp" 45 #include "runtime/mutexLocker.hpp" 46 #include "utilities/macros.hpp" 47 48 ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS) { 49 assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(), 50 "array klasses must be same size as InstanceKlass"); 51 52 int size = ArrayKlass::static_size(ObjArrayKlass::header_size()); 53 54 return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name); 55 } 56 57 ObjArrayKlass* ObjArrayKlass::allocate_objArray_klass(ClassLoaderData* loader_data, 58 int n, Klass* element_klass, TRAPS) { 59 60 // Eagerly allocate the direct array supertype. 61 Klass* super_klass = NULL; 62 if (!Universe::is_bootstrapping() || vmClasses::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(); 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() == 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_NULL); 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_NULL); 87 } 88 // Now retry from the beginning 89 ek = element_klass->array_klass(n, CHECK_NULL); 90 } // re-lock 91 return ObjArrayKlass::cast(ek); 92 } 93 } else { 94 // The element type is already Object. Object[] has direct super of Object. 95 super_klass = vmClasses::Object_klass(); 96 } 97 } 98 99 // Create type name for klass. 100 Symbol* name = NULL; 101 { 102 ResourceMark rm(THREAD); 103 char *name_str = element_klass->name()->as_C_string(); 104 int len = element_klass->name()->utf8_length(); 105 char *new_str = NEW_RESOURCE_ARRAY(char, len + 4); 106 int idx = 0; 107 new_str[idx++] = JVM_SIGNATURE_ARRAY; 108 if (element_klass->is_instance_klass()) { // it could be an array or simple type 109 new_str[idx++] = JVM_SIGNATURE_CLASS; 110 } 111 memcpy(&new_str[idx], name_str, len * sizeof(char)); 112 idx += len; 113 if (element_klass->is_instance_klass()) { 114 new_str[idx++] = JVM_SIGNATURE_ENDCLASS; 115 } 116 new_str[idx++] = '\0'; 117 name = SymbolTable::new_symbol(new_str); 118 } 119 120 // Initialize instance variables 121 ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, CHECK_NULL); 122 123 ModuleEntry* module = oak->module(); 124 assert(module != NULL, "No module entry for array"); 125 126 // Call complete_create_array_klass after all instance variables has been initialized. 127 ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_NULL); 128 129 // Add all classes to our internal class loader list here, 130 // including classes in the bootstrap (NULL) class loader. 131 // Do this step after creating the mirror so that if the 132 // mirror creation fails, loaded_classes_do() doesn't find 133 // an array class without a mirror. 134 loader_data->add_class(oak); 135 136 return oak; 137 } 138 139 ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name) : ArrayKlass(name, Kind) { 140 set_dimension(n); 141 set_element_klass(element_klass); 142 143 Klass* bk; 144 if (element_klass->is_objArray_klass()) { 145 bk = ObjArrayKlass::cast(element_klass)->bottom_klass(); 146 } else { 147 bk = element_klass; 148 } 149 assert(bk != NULL && (bk->is_instance_klass() || bk->is_typeArray_klass()), "invalid bottom klass"); 150 set_bottom_klass(bk); 151 set_class_loader_data(bk->class_loader_data()); 152 153 set_layout_helper(array_layout_helper(T_OBJECT)); 154 assert(is_array_klass(), "sanity"); 155 assert(is_objArray_klass(), "sanity"); 156 } 157 158 size_t ObjArrayKlass::oop_size(oop obj) const { 159 return objArrayOop(obj)->object_size(); 160 } 161 162 objArrayOop ObjArrayKlass::allocate(int length, TRAPS) { 163 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 164 size_t size = objArrayOopDesc::object_size(length); 165 return (objArrayOop)Universe::heap()->array_allocate(this, size, length, 166 /* do_zero */ true, THREAD); 167 } 168 169 oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) { 170 int length = *sizes; 171 // Call to lower_dimension uses this pointer, so most be called before a 172 // possible GC 173 Klass* ld_klass = lower_dimension(); 174 // If length < 0 allocate will throw an exception. 175 objArrayOop array = allocate(length, CHECK_NULL); 176 objArrayHandle h_array (THREAD, array); 177 if (rank > 1) { 178 if (length != 0) { 179 for (int index = 0; index < length; index++) { 180 ArrayKlass* ak = ArrayKlass::cast(ld_klass); 181 oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL); 182 h_array->obj_at_put(index, sub_array); 183 } 184 } else { 185 // Since this array dimension has zero length, nothing will be 186 // allocated, however the lower dimension values must be checked 187 // for illegal values. 188 for (int i = 0; i < rank - 1; ++i) { 189 sizes += 1; 190 if (*sizes < 0) { 191 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", *sizes)); 192 } 193 } 194 } 195 } 196 return h_array(); 197 } 198 199 // Either oop or narrowOop depending on UseCompressedOops. 200 void ObjArrayKlass::do_copy(arrayOop s, size_t src_offset, 201 arrayOop d, size_t dst_offset, int length, TRAPS) { 202 if (s == d) { 203 // since source and destination are equal we do not need conversion checks. 204 assert(length > 0, "sanity check"); 205 ArrayAccess<>::oop_arraycopy(s, src_offset, d, dst_offset, length); 206 } else { 207 // We have to make sure all elements conform to the destination array 208 Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass(); 209 Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass(); 210 if (stype == bound || stype->is_subtype_of(bound)) { 211 // elements are guaranteed to be subtypes, so no check necessary 212 ArrayAccess<ARRAYCOPY_DISJOINT>::oop_arraycopy(s, src_offset, d, dst_offset, length); 213 } else { 214 // slow case: need individual subtype checks 215 // note: don't use obj_at_put below because it includes a redundant store check 216 if (!ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST>::oop_arraycopy(s, src_offset, d, dst_offset, length)) { 217 ResourceMark rm(THREAD); 218 stringStream ss; 219 if (!bound->is_subtype_of(stype)) { 220 ss.print("arraycopy: type mismatch: can not copy %s[] into %s[]", 221 stype->external_name(), bound->external_name()); 222 } else { 223 // oop_arraycopy should return the index in the source array that 224 // contains the problematic oop. 225 ss.print("arraycopy: element type mismatch: can not cast one of the elements" 226 " of %s[] to the type of the destination array, %s", 227 stype->external_name(), bound->external_name()); 228 } 229 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string()); 230 } 231 } 232 } 233 } 234 235 void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d, 236 int dst_pos, int length, TRAPS) { 237 assert(s->is_objArray(), "must be obj array"); 238 239 if (!d->is_objArray()) { 240 ResourceMark rm(THREAD); 241 stringStream ss; 242 if (d->is_typeArray()) { 243 ss.print("arraycopy: type mismatch: can not copy object array[] into %s[]", 244 type2name_tab[ArrayKlass::cast(d->klass())->element_type()]); 245 } else { 246 ss.print("arraycopy: destination type %s is not an array", d->klass()->external_name()); 247 } 248 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string()); 249 } 250 251 // Check is all offsets and lengths are non negative 252 if (src_pos < 0 || dst_pos < 0 || length < 0) { 253 // Pass specific exception reason. 254 ResourceMark rm(THREAD); 255 stringStream ss; 256 if (src_pos < 0) { 257 ss.print("arraycopy: source index %d out of bounds for object array[%d]", 258 src_pos, s->length()); 259 } else if (dst_pos < 0) { 260 ss.print("arraycopy: destination index %d out of bounds for object array[%d]", 261 dst_pos, d->length()); 262 } else { 263 ss.print("arraycopy: length %d is negative", length); 264 } 265 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 266 } 267 // Check if the ranges are valid 268 if ((((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) || 269 (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length())) { 270 // Pass specific exception reason. 271 ResourceMark rm(THREAD); 272 stringStream ss; 273 if (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) { 274 ss.print("arraycopy: last source index %u out of bounds for object array[%d]", 275 (unsigned int) length + (unsigned int) src_pos, s->length()); 276 } else { 277 ss.print("arraycopy: last destination index %u out of bounds for object array[%d]", 278 (unsigned int) length + (unsigned int) dst_pos, d->length()); 279 } 280 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string()); 281 } 282 283 // Special case. Boundary cases must be checked first 284 // This allows the following call: copy_array(s, s.length(), d.length(), 0). 285 // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(), 286 // points to the right of the last element. 287 if (length==0) { 288 return; 289 } 290 if (UseCompressedOops) { 291 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(src_pos); 292 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(dst_pos); 293 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(s, src_offset, NULL) == 294 objArrayOop(s)->obj_at_addr<narrowOop>(src_pos), "sanity"); 295 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(d, dst_offset, NULL) == 296 objArrayOop(d)->obj_at_addr<narrowOop>(dst_pos), "sanity"); 297 do_copy(s, src_offset, d, dst_offset, length, CHECK); 298 } else { 299 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(src_pos); 300 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(dst_pos); 301 assert(arrayOopDesc::obj_offset_to_raw<oop>(s, src_offset, NULL) == 302 objArrayOop(s)->obj_at_addr<oop>(src_pos), "sanity"); 303 assert(arrayOopDesc::obj_offset_to_raw<oop>(d, dst_offset, NULL) == 304 objArrayOop(d)->obj_at_addr<oop>(dst_pos), "sanity"); 305 do_copy(s, src_offset, d, dst_offset, length, CHECK); 306 } 307 } 308 309 310 Klass* ObjArrayKlass::array_klass(int n, TRAPS) { 311 312 assert(dimension() <= n, "check order of chain"); 313 int dim = dimension(); 314 if (dim == n) return this; 315 316 // lock-free read needs acquire semantics 317 if (higher_dimension_acquire() == NULL) { 318 319 ResourceMark rm(THREAD); 320 { 321 // Ensure atomic creation of higher dimensions 322 MutexLocker mu(THREAD, MultiArray_lock); 323 324 // Check if another thread beat us 325 if (higher_dimension() == NULL) { 326 327 // Create multi-dim klass object and link them together 328 Klass* k = 329 ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, CHECK_NULL); 330 ObjArrayKlass* ak = ObjArrayKlass::cast(k); 331 ak->set_lower_dimension(this); 332 // use 'release' to pair with lock-free load 333 release_set_higher_dimension(ak); 334 assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass"); 335 } 336 } 337 } 338 339 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); 340 THREAD->check_possible_safepoint(); 341 return ak->array_klass(n, THREAD); 342 } 343 344 Klass* ObjArrayKlass::array_klass_or_null(int n) { 345 346 assert(dimension() <= n, "check order of chain"); 347 int dim = dimension(); 348 if (dim == n) return this; 349 350 // lock-free read needs acquire semantics 351 if (higher_dimension_acquire() == NULL) { 352 return NULL; 353 } 354 355 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); 356 return ak->array_klass_or_null(n); 357 } 358 359 Klass* ObjArrayKlass::array_klass(TRAPS) { 360 return array_klass(dimension() + 1, THREAD); 361 } 362 363 Klass* ObjArrayKlass::array_klass_or_null() { 364 return array_klass_or_null(dimension() + 1); 365 } 366 367 bool ObjArrayKlass::can_be_primary_super_slow() const { 368 if (!bottom_klass()->can_be_primary_super()) 369 // array of interfaces 370 return false; 371 else 372 return Klass::can_be_primary_super_slow(); 373 } 374 375 GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots, 376 Array<InstanceKlass*>* transitive_interfaces) { 377 assert(transitive_interfaces == NULL, "sanity"); 378 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... }; 379 const Array<Klass*>* elem_supers = element_klass()->secondary_supers(); 380 int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length(); 381 int num_secondaries = num_extra_slots + 2 + num_elem_supers; 382 if (num_secondaries == 2) { 383 // Must share this for correct bootstrapping! 384 set_secondary_supers(Universe::the_array_interfaces_array()); 385 return NULL; 386 } else { 387 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2); 388 secondaries->push(vmClasses::Cloneable_klass()); 389 secondaries->push(vmClasses::Serializable_klass()); 390 for (int i = 0; i < num_elem_supers; i++) { 391 Klass* elem_super = elem_supers->at(i); 392 Klass* array_super = elem_super->array_klass_or_null(); 393 assert(array_super != NULL, "must already have been created"); 394 secondaries->push(array_super); 395 } 396 return secondaries; 397 } 398 } 399 400 void ObjArrayKlass::initialize(TRAPS) { 401 bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass 402 } 403 404 void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) { 405 ArrayKlass::metaspace_pointers_do(it); 406 it->push(&_element_klass); 407 it->push(&_bottom_klass); 408 } 409 410 jint ObjArrayKlass::compute_modifier_flags() const { 411 // The modifier for an objectArray is the same as its element 412 if (element_klass() == NULL) { 413 assert(Universe::is_bootstrapping(), "partial objArray only at startup"); 414 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC; 415 } 416 // Return the flags of the bottom element type. 417 jint element_flags = bottom_klass()->compute_modifier_flags(); 418 419 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) 420 | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL); 421 } 422 423 ModuleEntry* ObjArrayKlass::module() const { 424 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); 425 // The array is defined in the module of its bottom class 426 return bottom_klass()->module(); 427 } 428 429 PackageEntry* ObjArrayKlass::package() const { 430 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); 431 return bottom_klass()->package(); 432 } 433 434 // Printing 435 436 void ObjArrayKlass::print_on(outputStream* st) const { 437 #ifndef PRODUCT 438 Klass::print_on(st); 439 st->print(" - instance klass: "); 440 element_klass()->print_value_on(st); 441 st->cr(); 442 #endif //PRODUCT 443 } 444 445 void ObjArrayKlass::print_value_on(outputStream* st) const { 446 assert(is_klass(), "must be klass"); 447 448 element_klass()->print_value_on(st); 449 st->print("[]"); 450 } 451 452 #ifndef PRODUCT 453 454 void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) { 455 ArrayKlass::oop_print_on(obj, st); 456 assert(obj->is_objArray(), "must be objArray"); 457 objArrayOop oa = objArrayOop(obj); 458 int print_len = MIN2((intx) oa->length(), MaxElementPrintSize); 459 for(int index = 0; index < print_len; index++) { 460 st->print(" - %3d : ", index); 461 if (oa->obj_at(index) != NULL) { 462 oa->obj_at(index)->print_value_on(st); 463 st->cr(); 464 } else { 465 st->print_cr("NULL"); 466 } 467 } 468 int remaining = oa->length() - print_len; 469 if (remaining > 0) { 470 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining); 471 } 472 } 473 474 #endif //PRODUCT 475 476 void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) { 477 assert(obj->is_objArray(), "must be objArray"); 478 st->print("a "); 479 element_klass()->print_value_on(st); 480 int len = objArrayOop(obj)->length(); 481 st->print("[%d] ", len); 482 if (obj != NULL) { 483 obj->print_address_on(st); 484 } else { 485 st->print_cr("NULL"); 486 } 487 } 488 489 const char* ObjArrayKlass::internal_name() const { 490 return external_name(); 491 } 492 493 494 // Verification 495 496 void ObjArrayKlass::verify_on(outputStream* st) { 497 ArrayKlass::verify_on(st); 498 guarantee(element_klass()->is_klass(), "should be klass"); 499 guarantee(bottom_klass()->is_klass(), "should be klass"); 500 Klass* bk = bottom_klass(); 501 guarantee(bk->is_instance_klass() || bk->is_typeArray_klass(), "invalid bottom klass"); 502 } 503 504 void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) { 505 ArrayKlass::oop_verify_on(obj, st); 506 guarantee(obj->is_objArray(), "must be objArray"); 507 objArrayOop oa = objArrayOop(obj); 508 for(int index = 0; index < oa->length(); index++) { 509 guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop"); 510 } 511 }