1 /* 2 * Copyright (c) 1997, 2024, 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 "cds/archiveUtils.hpp" 27 #include "cds/cdsConfig.hpp" 28 #include "cds/cdsEnumKlass.hpp" 29 #include "cds/classListWriter.hpp" 30 #include "cds/heapShared.hpp" 31 #include "cds/metaspaceShared.hpp" 32 #include "classfile/classFileParser.hpp" 33 #include "classfile/classFileStream.hpp" 34 #include "classfile/classLoader.hpp" 35 #include "classfile/classLoaderData.inline.hpp" 36 #include "classfile/javaClasses.hpp" 37 #include "classfile/moduleEntry.hpp" 38 #include "classfile/systemDictionary.hpp" 39 #include "classfile/systemDictionaryShared.hpp" 40 #include "classfile/verifier.hpp" 41 #include "classfile/vmClasses.hpp" 42 #include "classfile/vmSymbols.hpp" 43 #include "code/codeCache.hpp" 44 #include "code/dependencyContext.hpp" 45 #include "compiler/compilationPolicy.hpp" 46 #include "compiler/compileBroker.hpp" 47 #include "gc/shared/collectedHeap.inline.hpp" 48 #include "interpreter/bytecodeStream.hpp" 49 #include "interpreter/oopMapCache.hpp" 50 #include "interpreter/rewriter.hpp" 51 #include "jvm.h" 52 #include "jvmtifiles/jvmti.h" 53 #include "logging/log.hpp" 54 #include "logging/logMessage.hpp" 55 #include "logging/logStream.hpp" 56 #include "memory/allocation.inline.hpp" 57 #include "memory/iterator.inline.hpp" 58 #include "memory/metadataFactory.hpp" 59 #include "memory/metaspaceClosure.hpp" 60 #include "memory/oopFactory.hpp" 61 #include "memory/resourceArea.hpp" 62 #include "memory/universe.hpp" 63 #include "oops/fieldStreams.inline.hpp" 64 #include "oops/constantPool.hpp" 65 #include "oops/instanceClassLoaderKlass.hpp" 66 #include "oops/instanceKlass.inline.hpp" 67 #include "oops/instanceMirrorKlass.hpp" 68 #include "oops/instanceOop.hpp" 69 #include "oops/instanceStackChunkKlass.hpp" 70 #include "oops/klass.inline.hpp" 71 #include "oops/method.hpp" 72 #include "oops/oop.inline.hpp" 73 #include "oops/recordComponent.hpp" 74 #include "oops/symbol.hpp" 75 #include "oops/inlineKlass.hpp" 76 #include "prims/jvmtiExport.hpp" 77 #include "prims/jvmtiRedefineClasses.hpp" 78 #include "prims/jvmtiThreadState.hpp" 79 #include "prims/methodComparator.hpp" 80 #include "runtime/arguments.hpp" 81 #include "runtime/deoptimization.hpp" 82 #include "runtime/atomic.hpp" 83 #include "runtime/fieldDescriptor.inline.hpp" 84 #include "runtime/handles.inline.hpp" 85 #include "runtime/javaCalls.hpp" 86 #include "runtime/javaThread.inline.hpp" 87 #include "runtime/mutexLocker.hpp" 88 #include "runtime/orderAccess.hpp" 89 #include "runtime/os.inline.hpp" 90 #include "runtime/reflection.hpp" 91 #include "runtime/synchronizer.hpp" 92 #include "runtime/threads.hpp" 93 #include "services/classLoadingService.hpp" 94 #include "services/finalizerService.hpp" 95 #include "services/threadService.hpp" 96 #include "utilities/dtrace.hpp" 97 #include "utilities/events.hpp" 98 #include "utilities/macros.hpp" 99 #include "utilities/stringUtils.hpp" 100 #include "utilities/pair.hpp" 101 #ifdef COMPILER1 102 #include "c1/c1_Compiler.hpp" 103 #endif 104 #if INCLUDE_JFR 105 #include "jfr/jfrEvents.hpp" 106 #endif 107 108 #ifdef DTRACE_ENABLED 109 110 111 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 112 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 113 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 114 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 115 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 116 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 117 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 118 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 119 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 120 { \ 121 char* data = nullptr; \ 122 int len = 0; \ 123 Symbol* clss_name = name(); \ 124 if (clss_name != nullptr) { \ 125 data = (char*)clss_name->bytes(); \ 126 len = clss_name->utf8_length(); \ 127 } \ 128 HOTSPOT_CLASS_INITIALIZATION_##type( \ 129 data, len, (void*)class_loader(), thread_type); \ 130 } 131 132 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 133 { \ 134 char* data = nullptr; \ 135 int len = 0; \ 136 Symbol* clss_name = name(); \ 137 if (clss_name != nullptr) { \ 138 data = (char*)clss_name->bytes(); \ 139 len = clss_name->utf8_length(); \ 140 } \ 141 HOTSPOT_CLASS_INITIALIZATION_##type( \ 142 data, len, (void*)class_loader(), thread_type, wait); \ 143 } 144 145 #else // ndef DTRACE_ENABLED 146 147 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 148 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 149 150 #endif // ndef DTRACE_ENABLED 151 152 bool InstanceKlass::_finalization_enabled = true; 153 154 static inline bool is_class_loader(const Symbol* class_name, 155 const ClassFileParser& parser) { 156 assert(class_name != nullptr, "invariant"); 157 158 if (class_name == vmSymbols::java_lang_ClassLoader()) { 159 return true; 160 } 161 162 if (vmClasses::ClassLoader_klass_loaded()) { 163 const Klass* const super_klass = parser.super_klass(); 164 if (super_klass != nullptr) { 165 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) { 166 return true; 167 } 168 } 169 } 170 return false; 171 } 172 173 bool InstanceKlass::field_is_null_free_inline_type(int index) const { 174 return field(index).field_flags().is_null_free_inline_type(); 175 } 176 177 bool InstanceKlass::is_class_in_loadable_descriptors_attribute(Symbol* name) const { 178 if (_loadable_descriptors == nullptr) return false; 179 for (int i = 0; i < _loadable_descriptors->length(); i++) { 180 Symbol* class_name = _constants->klass_at_noresolve(_loadable_descriptors->at(i)); 181 if (class_name == name) return true; 182 } 183 return false; 184 } 185 186 static inline bool is_stack_chunk_class(const Symbol* class_name, 187 const ClassLoaderData* loader_data) { 188 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() && 189 loader_data->is_the_null_class_loader_data()); 190 } 191 192 // private: called to verify that k is a static member of this nest. 193 // We know that k is an instance class in the same package and hence the 194 // same classloader. 195 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const { 196 assert(!is_hidden(), "unexpected hidden class"); 197 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) { 198 if (log_is_enabled(Trace, class, nestmates)) { 199 ResourceMark rm(current); 200 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 201 k->external_name(), this->external_name()); 202 } 203 return false; 204 } 205 206 if (log_is_enabled(Trace, class, nestmates)) { 207 ResourceMark rm(current); 208 log_trace(class, nestmates)("Checking nest membership of %s in %s", 209 k->external_name(), this->external_name()); 210 } 211 212 // Check for the named class in _nest_members. 213 // We don't resolve, or load, any classes. 214 for (int i = 0; i < _nest_members->length(); i++) { 215 int cp_index = _nest_members->at(i); 216 Symbol* name = _constants->klass_name_at(cp_index); 217 if (name == k->name()) { 218 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index); 219 return true; 220 } 221 } 222 log_trace(class, nestmates)("- class is NOT a nest member!"); 223 return false; 224 } 225 226 // Called to verify that k is a permitted subclass of this class 227 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const { 228 Thread* current = Thread::current(); 229 assert(k != nullptr, "sanity check"); 230 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(), 231 "unexpected empty _permitted_subclasses array"); 232 233 if (log_is_enabled(Trace, class, sealed)) { 234 ResourceMark rm(current); 235 log_trace(class, sealed)("Checking for permitted subclass of %s in %s", 236 k->external_name(), this->external_name()); 237 } 238 239 // Check that the class and its super are in the same module. 240 if (k->module() != this->module()) { 241 ResourceMark rm(current); 242 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s", 243 k->external_name(), this->external_name()); 244 return false; 245 } 246 247 if (!k->is_public() && !is_same_class_package(k)) { 248 ResourceMark rm(current); 249 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s", 250 k->external_name(), this->external_name()); 251 return false; 252 } 253 254 for (int i = 0; i < _permitted_subclasses->length(); i++) { 255 int cp_index = _permitted_subclasses->at(i); 256 Symbol* name = _constants->klass_name_at(cp_index); 257 if (name == k->name()) { 258 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index); 259 return true; 260 } 261 } 262 log_trace(class, sealed)("- class is NOT a permitted subclass!"); 263 return false; 264 } 265 266 // Return nest-host class, resolving, validating and saving it if needed. 267 // In cases where this is called from a thread that cannot do classloading 268 // (such as a native JIT thread) then we simply return null, which in turn 269 // causes the access check to return false. Such code will retry the access 270 // from a more suitable environment later. Otherwise the _nest_host is always 271 // set once this method returns. 272 // Any errors from nest-host resolution must be preserved so they can be queried 273 // from higher-level access checking code, and reported as part of access checking 274 // exceptions. 275 // VirtualMachineErrors are propagated with a null return. 276 // Under any conditions where the _nest_host can be set to non-null the resulting 277 // value of it and, if applicable, the nest host resolution/validation error, 278 // are idempotent. 279 InstanceKlass* InstanceKlass::nest_host(TRAPS) { 280 InstanceKlass* nest_host_k = _nest_host; 281 if (nest_host_k != nullptr) { 282 return nest_host_k; 283 } 284 285 ResourceMark rm(THREAD); 286 287 // need to resolve and save our nest-host class. 288 if (_nest_host_index != 0) { // we have a real nest_host 289 // Before trying to resolve check if we're in a suitable context 290 bool can_resolve = THREAD->can_call_java(); 291 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) { 292 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 293 this->external_name()); 294 return nullptr; // sentinel to say "try again from a different context" 295 } 296 297 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 298 this->external_name(), 299 _constants->klass_name_at(_nest_host_index)->as_C_string()); 300 301 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 302 if (HAS_PENDING_EXCEPTION) { 303 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) { 304 return nullptr; // propagate VMEs 305 } 306 stringStream ss; 307 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string(); 308 ss.print("Nest host resolution of %s with host %s failed: ", 309 this->external_name(), target_host_class); 310 java_lang_Throwable::print(PENDING_EXCEPTION, &ss); 311 const char* msg = ss.as_string(true /* on C-heap */); 312 constantPoolHandle cph(THREAD, constants()); 313 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 314 CLEAR_PENDING_EXCEPTION; 315 316 log_trace(class, nestmates)("%s", msg); 317 } else { 318 // A valid nest-host is an instance class in the current package that lists this 319 // class as a nest member. If any of these conditions are not met the class is 320 // its own nest-host. 321 const char* error = nullptr; 322 323 // JVMS 5.4.4 indicates package check comes first 324 if (is_same_class_package(k)) { 325 // Now check actual membership. We can't be a member if our "host" is 326 // not an instance class. 327 if (k->is_instance_klass()) { 328 nest_host_k = InstanceKlass::cast(k); 329 bool is_member = nest_host_k->has_nest_member(THREAD, this); 330 if (is_member) { 331 _nest_host = nest_host_k; // save resolved nest-host value 332 333 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 334 this->external_name(), k->external_name()); 335 return nest_host_k; 336 } else { 337 error = "current type is not listed as a nest member"; 338 } 339 } else { 340 error = "host is not an instance class"; 341 } 342 } else { 343 error = "types are in different packages"; 344 } 345 346 // something went wrong, so record what and log it 347 { 348 stringStream ss; 349 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s", 350 this->external_name(), 351 this->class_loader_data()->loader_name_and_id(), 352 k->external_name(), 353 k->class_loader_data()->loader_name_and_id(), 354 error); 355 const char* msg = ss.as_string(true /* on C-heap */); 356 constantPoolHandle cph(THREAD, constants()); 357 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 358 log_trace(class, nestmates)("%s", msg); 359 } 360 } 361 } else { 362 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 363 this->external_name()); 364 } 365 366 // Either not in an explicit nest, or else an error occurred, so 367 // the nest-host is set to `this`. Any thread that sees this assignment 368 // will also see any setting of nest_host_error(), if applicable. 369 return (_nest_host = this); 370 } 371 372 // Dynamic nest member support: set this class's nest host to the given class. 373 // This occurs as part of the class definition, as soon as the instanceKlass 374 // has been created and doesn't require further resolution. The code: 375 // lookup().defineHiddenClass(bytes_for_X, NESTMATE); 376 // results in: 377 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost()) 378 // If it has an explicit _nest_host_index or _nest_members, these will be ignored. 379 // We also know the "host" is a valid nest-host in the same package so we can 380 // assert some of those facts. 381 void InstanceKlass::set_nest_host(InstanceKlass* host) { 382 assert(is_hidden(), "must be a hidden class"); 383 assert(host != nullptr, "null nest host specified"); 384 assert(_nest_host == nullptr, "current class has resolved nest-host"); 385 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s", 386 nest_host_error()); 387 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) || 388 (host->_nest_host == host), "proposed host is not a valid nest-host"); 389 // Can't assert this as package is not set yet: 390 // assert(is_same_class_package(host), "proposed host is in wrong package"); 391 392 if (log_is_enabled(Trace, class, nestmates)) { 393 ResourceMark rm; 394 const char* msg = ""; 395 // a hidden class does not expect a statically defined nest-host 396 if (_nest_host_index > 0) { 397 msg = "(the NestHost attribute in the current class is ignored)"; 398 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) { 399 msg = "(the NestMembers attribute in the current class is ignored)"; 400 } 401 log_trace(class, nestmates)("Injected type %s into the nest of %s %s", 402 this->external_name(), 403 host->external_name(), 404 msg); 405 } 406 // set dynamic nest host 407 _nest_host = host; 408 // Record dependency to keep nest host from being unloaded before this class. 409 ClassLoaderData* this_key = class_loader_data(); 410 assert(this_key != nullptr, "sanity"); 411 this_key->record_dependency(host); 412 } 413 414 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 415 // or we are k's nest_host - all of which is covered by comparing the two 416 // resolved_nest_hosts. 417 // Any exceptions (i.e. VMEs) are propagated. 418 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 419 420 assert(this != k, "this should be handled by higher-level code"); 421 422 // Per JVMS 5.4.4 we first resolve and validate the current class, then 423 // the target class k. 424 425 InstanceKlass* cur_host = nest_host(CHECK_false); 426 if (cur_host == nullptr) { 427 return false; 428 } 429 430 Klass* k_nest_host = k->nest_host(CHECK_false); 431 if (k_nest_host == nullptr) { 432 return false; 433 } 434 435 bool access = (cur_host == k_nest_host); 436 437 ResourceMark rm(THREAD); 438 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 439 this->external_name(), 440 access ? "" : "NOT ", 441 k->external_name()); 442 return access; 443 } 444 445 const char* InstanceKlass::nest_host_error() { 446 if (_nest_host_index == 0) { 447 return nullptr; 448 } else { 449 constantPoolHandle cph(Thread::current(), constants()); 450 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index); 451 } 452 } 453 454 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 455 const int size = InstanceKlass::size(parser.vtable_size(), 456 parser.itable_size(), 457 nonstatic_oop_map_size(parser.total_oop_map_count()), 458 parser.is_interface(), 459 parser.is_inline_type()); 460 461 const Symbol* const class_name = parser.class_name(); 462 assert(class_name != nullptr, "invariant"); 463 ClassLoaderData* loader_data = parser.loader_data(); 464 assert(loader_data != nullptr, "invariant"); 465 466 InstanceKlass* ik; 467 468 // Allocation 469 if (parser.is_instance_ref_klass()) { 470 // java.lang.ref.Reference 471 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 472 } else if (class_name == vmSymbols::java_lang_Class()) { 473 // mirror - java.lang.Class 474 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 475 } else if (is_stack_chunk_class(class_name, loader_data)) { 476 // stack chunk 477 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser); 478 } else if (is_class_loader(class_name, parser)) { 479 // class loader - java.lang.ClassLoader 480 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 481 } else if (parser.is_inline_type()) { 482 // inline type 483 ik = new (loader_data, size, THREAD) InlineKlass(parser); 484 } else { 485 // normal 486 ik = new (loader_data, size, THREAD) InstanceKlass(parser); 487 } 488 489 // Check for pending exception before adding to the loader data and incrementing 490 // class count. Can get OOM here. 491 if (HAS_PENDING_EXCEPTION) { 492 return nullptr; 493 } 494 495 #ifdef ASSERT 496 ik->bounds_check((address) ik->start_of_vtable(), false, size); 497 ik->bounds_check((address) ik->start_of_itable(), false, size); 498 ik->bounds_check((address) ik->end_of_itable(), true, size); 499 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size); 500 #endif //ASSERT 501 return ik; 502 } 503 504 #ifndef PRODUCT 505 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const { 506 const char* bad = nullptr; 507 address end = nullptr; 508 if (addr < (address)this) { 509 bad = "before"; 510 } else if (addr == (address)this) { 511 if (edge_ok) return true; 512 bad = "just before"; 513 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) { 514 if (edge_ok) return true; 515 bad = "just after"; 516 } else if (addr > end) { 517 bad = "after"; 518 } else { 519 return true; 520 } 521 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]", 522 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end); 523 Verbose = WizardMode = true; this->print(); //@@ 524 return false; 525 } 526 #endif //PRODUCT 527 528 // copy method ordering from resource area to Metaspace 529 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 530 if (m != nullptr) { 531 // allocate a new array and copy contents (memcpy?) 532 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 533 for (int i = 0; i < m->length(); i++) { 534 _method_ordering->at_put(i, m->at(i)); 535 } 536 } else { 537 _method_ordering = Universe::the_empty_int_array(); 538 } 539 } 540 541 // create a new array of vtable_indices for default methods 542 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 543 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 544 assert(default_vtable_indices() == nullptr, "only create once"); 545 set_default_vtable_indices(vtable_indices); 546 return vtable_indices; 547 } 548 549 550 InstanceKlass::InstanceKlass() { 551 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS"); 552 } 553 554 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) : 555 Klass(kind), 556 _nest_members(nullptr), 557 _nest_host(nullptr), 558 _permitted_subclasses(nullptr), 559 _record_components(nullptr), 560 _static_field_size(parser.static_field_size()), 561 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 562 _itable_len(parser.itable_size()), 563 _nest_host_index(0), 564 _init_state(allocated), 565 _reference_type(reference_type), 566 _init_thread(nullptr), 567 _inline_type_field_klasses(nullptr), 568 _null_marker_offsets(nullptr), 569 _loadable_descriptors(nullptr), 570 _adr_inlineklass_fixed_block(nullptr) 571 { 572 set_vtable_length(parser.vtable_size()); 573 set_access_flags(parser.access_flags()); 574 if (parser.is_hidden()) set_is_hidden(); 575 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 576 false)); 577 if (parser.has_inline_fields()) { 578 set_has_inline_type_fields(); 579 } 580 581 assert(nullptr == _methods, "underlying memory not zeroed?"); 582 assert(is_instance_klass(), "is layout incorrect?"); 583 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 584 } 585 586 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 587 Array<Method*>* methods) { 588 if (methods != nullptr && methods != Universe::the_empty_method_array() && 589 !methods->is_shared()) { 590 for (int i = 0; i < methods->length(); i++) { 591 Method* method = methods->at(i); 592 if (method == nullptr) continue; // maybe null if error processing 593 // Only want to delete methods that are not executing for RedefineClasses. 594 // The previous version will point to them so they're not totally dangling 595 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 596 MetadataFactory::free_metadata(loader_data, method); 597 } 598 MetadataFactory::free_array<Method*>(loader_data, methods); 599 } 600 } 601 602 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 603 const Klass* super_klass, 604 Array<InstanceKlass*>* local_interfaces, 605 Array<InstanceKlass*>* transitive_interfaces) { 606 // Only deallocate transitive interfaces if not empty, same as super class 607 // or same as local interfaces. See code in parseClassFile. 608 Array<InstanceKlass*>* ti = transitive_interfaces; 609 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 610 // check that the interfaces don't come from super class 611 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr : 612 InstanceKlass::cast(super_klass)->transitive_interfaces(); 613 if (ti != sti && ti != nullptr && !ti->is_shared()) { 614 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 615 } 616 } 617 618 // local interfaces can be empty 619 if (local_interfaces != Universe::the_empty_instance_klass_array() && 620 local_interfaces != nullptr && !local_interfaces->is_shared()) { 621 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 622 } 623 } 624 625 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 626 Array<RecordComponent*>* record_components) { 627 if (record_components != nullptr && !record_components->is_shared()) { 628 for (int i = 0; i < record_components->length(); i++) { 629 RecordComponent* record_component = record_components->at(i); 630 MetadataFactory::free_metadata(loader_data, record_component); 631 } 632 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 633 } 634 } 635 636 // This function deallocates the metadata and C heap pointers that the 637 // InstanceKlass points to. 638 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 639 // Orphan the mirror first, CMS thinks it's still live. 640 if (java_mirror() != nullptr) { 641 java_lang_Class::set_klass(java_mirror(), nullptr); 642 } 643 644 // Also remove mirror from handles 645 loader_data->remove_handle(_java_mirror); 646 647 // Need to take this class off the class loader data list. 648 loader_data->remove_class(this); 649 650 // The array_klass for this class is created later, after error handling. 651 // For class redefinition, we keep the original class so this scratch class 652 // doesn't have an array class. Either way, assert that there is nothing 653 // to deallocate. 654 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet"); 655 656 // Release C heap allocated data that this points to, which includes 657 // reference counting symbol names. 658 // Can't release the constant pool or MethodData C heap data here because the constant 659 // pool can be deallocated separately from the InstanceKlass for default methods and 660 // redefine classes. MethodData can also be released separately. 661 release_C_heap_structures(/* release_sub_metadata */ false); 662 663 deallocate_methods(loader_data, methods()); 664 set_methods(nullptr); 665 666 deallocate_record_components(loader_data, record_components()); 667 set_record_components(nullptr); 668 669 if (method_ordering() != nullptr && 670 method_ordering() != Universe::the_empty_int_array() && 671 !method_ordering()->is_shared()) { 672 MetadataFactory::free_array<int>(loader_data, method_ordering()); 673 } 674 set_method_ordering(nullptr); 675 676 // default methods can be empty 677 if (default_methods() != nullptr && 678 default_methods() != Universe::the_empty_method_array() && 679 !default_methods()->is_shared()) { 680 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 681 } 682 // Do NOT deallocate the default methods, they are owned by superinterfaces. 683 set_default_methods(nullptr); 684 685 // default methods vtable indices can be empty 686 if (default_vtable_indices() != nullptr && 687 !default_vtable_indices()->is_shared()) { 688 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 689 } 690 set_default_vtable_indices(nullptr); 691 692 693 // This array is in Klass, but remove it with the InstanceKlass since 694 // this place would be the only caller and it can share memory with transitive 695 // interfaces. 696 if (secondary_supers() != nullptr && 697 secondary_supers() != Universe::the_empty_klass_array() && 698 // see comments in compute_secondary_supers about the following cast 699 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 700 !secondary_supers()->is_shared()) { 701 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 702 } 703 set_secondary_supers(nullptr); 704 705 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 706 set_transitive_interfaces(nullptr); 707 set_local_interfaces(nullptr); 708 709 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) { 710 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream()); 711 } 712 set_fieldinfo_stream(nullptr); 713 714 if (fields_status() != nullptr && !fields_status()->is_shared()) { 715 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status()); 716 } 717 set_fields_status(nullptr); 718 719 if (inline_type_field_klasses_array() != nullptr) { 720 MetadataFactory::free_array<InlineKlass*>(loader_data, inline_type_field_klasses_array()); 721 set_inline_type_field_klasses_array(nullptr); 722 } 723 724 if (null_marker_offsets_array() != nullptr) { 725 MetadataFactory::free_array<int>(loader_data, null_marker_offsets_array()); 726 set_null_marker_offsets_array(nullptr); 727 } 728 729 // If a method from a redefined class is using this constant pool, don't 730 // delete it, yet. The new class's previous version will point to this. 731 if (constants() != nullptr) { 732 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 733 if (!constants()->is_shared()) { 734 MetadataFactory::free_metadata(loader_data, constants()); 735 } 736 // Delete any cached resolution errors for the constant pool 737 SystemDictionary::delete_resolution_error(constants()); 738 739 set_constants(nullptr); 740 } 741 742 if (inner_classes() != nullptr && 743 inner_classes() != Universe::the_empty_short_array() && 744 !inner_classes()->is_shared()) { 745 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 746 } 747 set_inner_classes(nullptr); 748 749 if (nest_members() != nullptr && 750 nest_members() != Universe::the_empty_short_array() && 751 !nest_members()->is_shared()) { 752 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 753 } 754 set_nest_members(nullptr); 755 756 if (permitted_subclasses() != nullptr && 757 permitted_subclasses() != Universe::the_empty_short_array() && 758 !permitted_subclasses()->is_shared()) { 759 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses()); 760 } 761 set_permitted_subclasses(nullptr); 762 763 if (loadable_descriptors() != nullptr && 764 loadable_descriptors() != Universe::the_empty_short_array() && 765 !loadable_descriptors()->is_shared()) { 766 MetadataFactory::free_array<jushort>(loader_data, loadable_descriptors()); 767 } 768 set_loadable_descriptors(nullptr); 769 770 // We should deallocate the Annotations instance if it's not in shared spaces. 771 if (annotations() != nullptr && !annotations()->is_shared()) { 772 MetadataFactory::free_metadata(loader_data, annotations()); 773 } 774 set_annotations(nullptr); 775 776 SystemDictionaryShared::handle_class_unloading(this); 777 778 #if INCLUDE_CDS_JAVA_HEAP 779 if (CDSConfig::is_dumping_heap()) { 780 HeapShared::remove_scratch_objects(this); 781 } 782 #endif 783 } 784 785 bool InstanceKlass::is_record() const { 786 return _record_components != nullptr && 787 is_final() && 788 java_super() == vmClasses::Record_klass(); 789 } 790 791 bool InstanceKlass::is_sealed() const { 792 return _permitted_subclasses != nullptr && 793 _permitted_subclasses != Universe::the_empty_short_array(); 794 } 795 796 bool InstanceKlass::should_be_initialized() const { 797 return !is_initialized(); 798 } 799 800 klassItable InstanceKlass::itable() const { 801 return klassItable(const_cast<InstanceKlass*>(this)); 802 } 803 804 // JVMTI spec thinks there are signers and protection domain in the 805 // instanceKlass. These accessors pretend these fields are there. 806 // The hprof specification also thinks these fields are in InstanceKlass. 807 oop InstanceKlass::protection_domain() const { 808 // return the protection_domain from the mirror 809 return java_lang_Class::protection_domain(java_mirror()); 810 } 811 812 objArrayOop InstanceKlass::signers() const { 813 // return the signers from the mirror 814 return java_lang_Class::signers(java_mirror()); 815 } 816 817 oop InstanceKlass::init_lock() const { 818 // return the init lock from the mirror 819 oop lock = java_lang_Class::init_lock(java_mirror()); 820 // Prevent reordering with any access of initialization state 821 OrderAccess::loadload(); 822 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state 823 "only fully initialized state can have a null lock"); 824 return lock; 825 } 826 827 // Set the initialization lock to null so the object can be GC'ed. Any racing 828 // threads to get this lock will see a null lock and will not lock. 829 // That's okay because they all check for initialized state after getting 830 // the lock and return. 831 void InstanceKlass::fence_and_clear_init_lock() { 832 // make sure previous stores are all done, notably the init_state. 833 OrderAccess::storestore(); 834 java_lang_Class::clear_init_lock(java_mirror()); 835 assert(!is_not_initialized(), "class must be initialized now"); 836 } 837 838 839 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 840 // process. The step comments refers to the procedure described in that section. 841 // Note: implementation moved to static method to expose the this pointer. 842 void InstanceKlass::initialize(TRAPS) { 843 if (this->should_be_initialized()) { 844 initialize_impl(CHECK); 845 // Note: at this point the class may be initialized 846 // OR it may be in the state of being initialized 847 // in case of recursive initialization! 848 } else { 849 assert(is_initialized(), "sanity check"); 850 } 851 } 852 853 854 bool InstanceKlass::verify_code(TRAPS) { 855 // 1) Verify the bytecodes 856 return Verifier::verify(this, should_verify_class(), THREAD); 857 } 858 859 void InstanceKlass::link_class(TRAPS) { 860 assert(is_loaded(), "must be loaded"); 861 if (!is_linked()) { 862 link_class_impl(CHECK); 863 } 864 } 865 866 // Called to verify that a class can link during initialization, without 867 // throwing a VerifyError. 868 bool InstanceKlass::link_class_or_fail(TRAPS) { 869 assert(is_loaded(), "must be loaded"); 870 if (!is_linked()) { 871 link_class_impl(CHECK_false); 872 } 873 return is_linked(); 874 } 875 876 bool InstanceKlass::link_class_impl(TRAPS) { 877 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) { 878 // This is for CDS static dump only -- we use the in_error_state to indicate that 879 // the class has failed verification. Throwing the NoClassDefFoundError here is just 880 // a convenient way to stop repeat attempts to verify the same (bad) class. 881 // 882 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 883 // if we are executing Java code. This is not a problem for CDS dumping phase since 884 // it doesn't execute any Java code. 885 ResourceMark rm(THREAD); 886 Exceptions::fthrow(THREAD_AND_LOCATION, 887 vmSymbols::java_lang_NoClassDefFoundError(), 888 "Class %s, or one of its supertypes, failed class initialization", 889 external_name()); 890 return false; 891 } 892 // return if already verified 893 if (is_linked()) { 894 return true; 895 } 896 897 // Timing 898 // timer handles recursion 899 JavaThread* jt = THREAD; 900 901 // link super class before linking this class 902 Klass* super_klass = super(); 903 if (super_klass != nullptr) { 904 if (super_klass->is_interface()) { // check if super class is an interface 905 ResourceMark rm(THREAD); 906 Exceptions::fthrow( 907 THREAD_AND_LOCATION, 908 vmSymbols::java_lang_IncompatibleClassChangeError(), 909 "class %s has interface %s as super class", 910 external_name(), 911 super_klass->external_name() 912 ); 913 return false; 914 } 915 916 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 917 ik_super->link_class_impl(CHECK_false); 918 } 919 920 // link all interfaces implemented by this class before linking this class 921 Array<InstanceKlass*>* interfaces = local_interfaces(); 922 int num_interfaces = interfaces->length(); 923 for (int index = 0; index < num_interfaces; index++) { 924 InstanceKlass* interk = interfaces->at(index); 925 interk->link_class_impl(CHECK_false); 926 } 927 928 929 // If a class declares a method that uses an inline class as an argument 930 // type or return inline type, this inline class must be loaded during the 931 // linking of this class because size and properties of the inline class 932 // must be known in order to be able to perform inline type optimizations. 933 // The implementation below is an approximation of this rule, the code 934 // iterates over all methods of the current class (including overridden 935 // methods), not only the methods declared by this class. This 936 // approximation makes the code simpler, and doesn't change the semantic 937 // because classes declaring methods overridden by the current class are 938 // linked (and have performed their own pre-loading) before the linking 939 // of the current class. 940 941 942 // Note: 943 // Inline class types are loaded during 944 // the loading phase (see ClassFileParser::post_process_parsed_stream()). 945 // Inline class types used as element types for array creation 946 // are not pre-loaded. Their loading is triggered by either anewarray 947 // or multianewarray bytecodes. 948 949 // Could it be possible to do the following processing only if the 950 // class uses inline types? 951 if (EnableValhalla) { 952 ResourceMark rm(THREAD); 953 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 954 if (fs.is_null_free_inline_type() && fs.access_flags().is_static()) { 955 Symbol* sig = fs.signature(); 956 TempNewSymbol s = Signature::strip_envelope(sig); 957 if (s != name()) { 958 log_info(class, preload)("Preloading class %s during linking of class %s. Cause: a null-free static field is declared with this type", s->as_C_string(), name()->as_C_string()); 959 Klass* klass = SystemDictionary::resolve_or_fail(s, 960 Handle(THREAD, class_loader()), Handle(THREAD, protection_domain()), true, 961 CHECK_false); 962 if (HAS_PENDING_EXCEPTION) { 963 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) failed: %s", 964 s->as_C_string(), name()->as_C_string(), PENDING_EXCEPTION->klass()->name()->as_C_string()); 965 return false; // Exception is still pending 966 } 967 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: null-free static field) succeeded", 968 s->as_C_string(), name()->as_C_string()); 969 assert(klass != nullptr, "Sanity check"); 970 if (!klass->is_inline_klass()) { 971 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(), 972 err_msg("class %s expects class %s to be a value class but it is an identity class", 973 name()->as_C_string(), klass->external_name()), false); 974 } 975 if (klass->is_abstract()) { 976 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(), 977 err_msg("Class %s expects class %s to be concrete value class, but it is an abstract class", 978 name()->as_C_string(), 979 InstanceKlass::cast(klass)->external_name()), false); 980 } 981 InstanceKlass* ik = InstanceKlass::cast(klass); 982 if (!ik->is_implicitly_constructible()) { 983 THROW_MSG_(vmSymbols::java_lang_IncompatibleClassChangeError(), 984 err_msg("class %s is not implicitly constructible and it is used in a null restricted static field (not supported)", 985 klass->external_name()), false); 986 } 987 // the inline_type_field_klasses_array might have been loaded with CDS, so update only if not already set and check consistency 988 if (inline_type_field_klasses_array()->at(fs.index()) == nullptr) { 989 set_inline_type_field_klass(fs.index(), InlineKlass::cast(ik)); 990 } 991 assert(get_inline_type_field_klass(fs.index()) == ik, "Must match"); 992 } else { 993 if (inline_type_field_klasses_array()->at(fs.index()) == nullptr) { 994 set_inline_type_field_klass(fs.index(), InlineKlass::cast(this)); 995 } 996 assert(get_inline_type_field_klass(fs.index()) == this, "Must match"); 997 } 998 } 999 } 1000 1001 // Aggressively preloading all classes from the LoadableDescriptors attribute 1002 if (loadable_descriptors() != nullptr) { 1003 HandleMark hm(THREAD); 1004 for (int i = 0; i < loadable_descriptors()->length(); i++) { 1005 Symbol* sig = constants()->symbol_at(loadable_descriptors()->at(i)); 1006 if (!Signature::has_envelope(sig)) continue; 1007 TempNewSymbol class_name = Signature::strip_envelope(sig); 1008 if (class_name == name()) continue; 1009 log_info(class, preload)("Preloading class %s during linking of class %s because of the class is listed in the LoadableDescriptors attribute", sig->as_C_string(), name()->as_C_string()); 1010 oop loader = class_loader(); 1011 oop protection_domain = this->protection_domain(); 1012 Klass* klass = SystemDictionary::resolve_or_null(class_name, 1013 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD); 1014 if (HAS_PENDING_EXCEPTION) { 1015 CLEAR_PENDING_EXCEPTION; 1016 } 1017 if (klass != nullptr) { 1018 log_info(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) succeeded", class_name->as_C_string(), name()->as_C_string()); 1019 if (!klass->is_inline_klass()) { 1020 // Non value class are allowed by the current spec, but it could be an indication of an issue so let's log a warning 1021 log_warning(class, preload)("Preloading class %s during linking of class %s (cause: LoadableDescriptors attribute) but loaded class is not a value class", class_name->as_C_string(), name()->as_C_string()); 1022 } 1023 } else { 1024 log_warning(class, preload)("Preloading of class %s during linking of class %s (cause: LoadableDescriptors attribute) failed", class_name->as_C_string(), name()->as_C_string()); 1025 } 1026 } 1027 } 1028 } 1029 1030 // in case the class is linked in the process of linking its superclasses 1031 if (is_linked()) { 1032 return true; 1033 } 1034 1035 // trace only the link time for this klass that includes 1036 // the verification time 1037 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 1038 ClassLoader::perf_class_link_selftime(), 1039 ClassLoader::perf_classes_linked(), 1040 jt->get_thread_stat()->perf_recursion_counts_addr(), 1041 jt->get_thread_stat()->perf_timers_addr(), 1042 PerfClassTraceTime::CLASS_LINK); 1043 1044 // verification & rewriting 1045 { 1046 HandleMark hm(THREAD); 1047 Handle h_init_lock(THREAD, init_lock()); 1048 ObjectLocker ol(h_init_lock, jt); 1049 // rewritten will have been set if loader constraint error found 1050 // on an earlier link attempt 1051 // don't verify or rewrite if already rewritten 1052 // 1053 1054 if (!is_linked()) { 1055 if (!is_rewritten()) { 1056 if (is_shared()) { 1057 assert(!verified_at_dump_time(), "must be"); 1058 } 1059 { 1060 bool verify_ok = verify_code(THREAD); 1061 if (!verify_ok) { 1062 return false; 1063 } 1064 } 1065 1066 // Just in case a side-effect of verify linked this class already 1067 // (which can sometimes happen since the verifier loads classes 1068 // using custom class loaders, which are free to initialize things) 1069 if (is_linked()) { 1070 return true; 1071 } 1072 1073 // also sets rewritten 1074 rewrite_class(CHECK_false); 1075 } else if (is_shared()) { 1076 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 1077 } 1078 1079 // relocate jsrs and link methods after they are all rewritten 1080 link_methods(CHECK_false); 1081 1082 // Initialize the vtable and interface table after 1083 // methods have been rewritten since rewrite may 1084 // fabricate new Method*s. 1085 // also does loader constraint checking 1086 // 1087 // initialize_vtable and initialize_itable need to be rerun 1088 // for a shared class if 1089 // 1) the class is loaded by custom class loader or 1090 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or 1091 // 3) the class was not verified during dump time 1092 bool need_init_table = true; 1093 if (is_shared() && verified_at_dump_time() && 1094 SystemDictionaryShared::check_linking_constraints(THREAD, this)) { 1095 need_init_table = false; 1096 } 1097 if (need_init_table) { 1098 vtable().initialize_vtable_and_check_constraints(CHECK_false); 1099 itable().initialize_itable_and_check_constraints(CHECK_false); 1100 } 1101 #ifdef ASSERT 1102 vtable().verify(tty, true); 1103 // In case itable verification is ever added. 1104 // itable().verify(tty, true); 1105 #endif 1106 if (Universe::is_fully_initialized()) { 1107 DeoptimizationScope deopt_scope; 1108 { 1109 // Now mark all code that assumes the class is not linked. 1110 // Set state under the Compile_lock also. 1111 MutexLocker ml(THREAD, Compile_lock); 1112 1113 set_init_state(linked); 1114 CodeCache::mark_dependents_on(&deopt_scope, this); 1115 } 1116 // Perform the deopt handshake outside Compile_lock. 1117 deopt_scope.deoptimize_marked(); 1118 } else { 1119 set_init_state(linked); 1120 } 1121 if (JvmtiExport::should_post_class_prepare()) { 1122 JvmtiExport::post_class_prepare(THREAD, this); 1123 } 1124 } 1125 } 1126 return true; 1127 } 1128 1129 // Rewrite the byte codes of all of the methods of a class. 1130 // The rewriter must be called exactly once. Rewriting must happen after 1131 // verification but before the first method of the class is executed. 1132 void InstanceKlass::rewrite_class(TRAPS) { 1133 assert(is_loaded(), "must be loaded"); 1134 if (is_rewritten()) { 1135 assert(is_shared(), "rewriting an unshared class?"); 1136 return; 1137 } 1138 Rewriter::rewrite(this, CHECK); 1139 set_rewritten(); 1140 } 1141 1142 // Now relocate and link method entry points after class is rewritten. 1143 // This is outside is_rewritten flag. In case of an exception, it can be 1144 // executed more than once. 1145 void InstanceKlass::link_methods(TRAPS) { 1146 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time()); 1147 1148 int len = methods()->length(); 1149 for (int i = len-1; i >= 0; i--) { 1150 methodHandle m(THREAD, methods()->at(i)); 1151 1152 // Set up method entry points for compiler and interpreter . 1153 m->link_method(m, CHECK); 1154 } 1155 } 1156 1157 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 1158 void InstanceKlass::initialize_super_interfaces(TRAPS) { 1159 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 1160 for (int i = 0; i < local_interfaces()->length(); ++i) { 1161 InstanceKlass* ik = local_interfaces()->at(i); 1162 1163 // Initialization is depth first search ie. we start with top of the inheritance tree 1164 // has_nonstatic_concrete_methods drives searching superinterfaces since it 1165 // means has_nonstatic_concrete_methods in its superinterface hierarchy 1166 if (ik->has_nonstatic_concrete_methods()) { 1167 ik->initialize_super_interfaces(CHECK); 1168 } 1169 1170 // Only initialize() interfaces that "declare" concrete methods. 1171 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 1172 ik->initialize(CHECK); 1173 } 1174 } 1175 } 1176 1177 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>; 1178 static InitializationErrorTable* _initialization_error_table; 1179 1180 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) { 1181 // Create the same exception with a message indicating the thread name, 1182 // and the StackTraceElements. 1183 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception); 1184 ResourceMark rm(current); 1185 if (init_error.is_null()) { 1186 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name()); 1187 1188 // We failed to create the new exception, most likely due to either out-of-memory or 1189 // a stackoverflow error. If the original exception was either of those then we save 1190 // the shared, pre-allocated, stackless, instance of that exception. 1191 if (exception->klass() == vmClasses::StackOverflowError_klass()) { 1192 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name()); 1193 init_error = Handle(current, Universe::class_init_stack_overflow_error()); 1194 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) { 1195 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name()); 1196 init_error = Handle(current, Universe::class_init_out_of_memory_error()); 1197 } else { 1198 return; 1199 } 1200 } 1201 1202 MutexLocker ml(current, ClassInitError_lock); 1203 OopHandle elem = OopHandle(Universe::vm_global(), init_error()); 1204 bool created; 1205 if (_initialization_error_table == nullptr) { 1206 _initialization_error_table = new (mtClass) InitializationErrorTable(); 1207 } 1208 _initialization_error_table->put_if_absent(this, elem, &created); 1209 assert(created, "Initialization is single threaded"); 1210 log_trace(class, init)("Initialization error added for class %s", external_name()); 1211 } 1212 1213 oop InstanceKlass::get_initialization_error(JavaThread* current) { 1214 MutexLocker ml(current, ClassInitError_lock); 1215 if (_initialization_error_table == nullptr) { 1216 return nullptr; 1217 } 1218 OopHandle* h = _initialization_error_table->get(this); 1219 return (h != nullptr) ? h->resolve() : nullptr; 1220 } 1221 1222 // Need to remove entries for unloaded classes. 1223 void InstanceKlass::clean_initialization_error_table() { 1224 struct InitErrorTableCleaner { 1225 bool do_entry(const InstanceKlass* ik, OopHandle h) { 1226 if (!ik->is_loader_alive()) { 1227 h.release(Universe::vm_global()); 1228 return true; 1229 } else { 1230 return false; 1231 } 1232 } 1233 }; 1234 1235 assert_locked_or_safepoint(ClassInitError_lock); 1236 InitErrorTableCleaner cleaner; 1237 if (_initialization_error_table != nullptr) { 1238 _initialization_error_table->unlink(&cleaner); 1239 } 1240 } 1241 1242 void InstanceKlass::initialize_impl(TRAPS) { 1243 HandleMark hm(THREAD); 1244 1245 // Make sure klass is linked (verified) before initialization 1246 // A class could already be verified, since it has been reflected upon. 1247 link_class(CHECK); 1248 1249 DTRACE_CLASSINIT_PROBE(required, -1); 1250 1251 bool wait = false; 1252 1253 JavaThread* jt = THREAD; 1254 1255 bool debug_logging_enabled = log_is_enabled(Debug, class, init); 1256 1257 // refer to the JVM book page 47 for description of steps 1258 // Step 1 1259 { 1260 Handle h_init_lock(THREAD, init_lock()); 1261 ObjectLocker ol(h_init_lock, jt); 1262 1263 // Step 2 1264 // If we were to use wait() instead of waitInterruptibly() then 1265 // we might end up throwing IE from link/symbol resolution sites 1266 // that aren't expected to throw. This would wreak havoc. See 6320309. 1267 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1268 if (debug_logging_enabled) { 1269 ResourceMark rm(jt); 1270 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"", 1271 jt->name(), external_name(), init_thread_name()); 1272 } 1273 wait = true; 1274 jt->set_class_to_be_initialized(this); 1275 ol.wait_uninterruptibly(jt); 1276 jt->set_class_to_be_initialized(nullptr); 1277 } 1278 1279 // Step 3 1280 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1281 if (debug_logging_enabled) { 1282 ResourceMark rm(jt); 1283 log_debug(class, init)("Thread \"%s\" recursively initializing %s", 1284 jt->name(), external_name()); 1285 } 1286 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1287 return; 1288 } 1289 1290 // Step 4 1291 if (is_initialized()) { 1292 if (debug_logging_enabled) { 1293 ResourceMark rm(jt); 1294 log_debug(class, init)("Thread \"%s\" found %s already initialized", 1295 jt->name(), external_name()); 1296 } 1297 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1298 return; 1299 } 1300 1301 // Step 5 1302 if (is_in_error_state()) { 1303 if (debug_logging_enabled) { 1304 ResourceMark rm(jt); 1305 log_debug(class, init)("Thread \"%s\" found %s is in error state", 1306 jt->name(), external_name()); 1307 } 1308 1309 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1310 ResourceMark rm(THREAD); 1311 Handle cause(THREAD, get_initialization_error(THREAD)); 1312 1313 stringStream ss; 1314 ss.print("Could not initialize class %s", external_name()); 1315 if (cause.is_null()) { 1316 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string()); 1317 } else { 1318 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(), 1319 ss.as_string(), cause); 1320 } 1321 } else { 1322 1323 // Step 6 1324 set_init_state(being_initialized); 1325 set_init_thread(jt); 1326 if (debug_logging_enabled) { 1327 ResourceMark rm(jt); 1328 log_debug(class, init)("Thread \"%s\" is initializing %s", 1329 jt->name(), external_name()); 1330 } 1331 } 1332 } 1333 1334 // Pre-allocating an instance of the default value 1335 if (is_inline_klass()) { 1336 InlineKlass* vk = InlineKlass::cast(this); 1337 oop val = vk->allocate_instance(THREAD); 1338 if (HAS_PENDING_EXCEPTION) { 1339 Handle e(THREAD, PENDING_EXCEPTION); 1340 CLEAR_PENDING_EXCEPTION; 1341 { 1342 EXCEPTION_MARK; 1343 add_initialization_error(THREAD, e); 1344 // Locks object, set state, and notify all waiting threads 1345 set_initialization_state_and_notify(initialization_error, THREAD); 1346 CLEAR_PENDING_EXCEPTION; 1347 } 1348 THROW_OOP(e()); 1349 } 1350 vk->set_default_value(val); 1351 } 1352 1353 // Step 7 1354 // Next, if C is a class rather than an interface, initialize it's super class and super 1355 // interfaces. 1356 if (!is_interface()) { 1357 Klass* super_klass = super(); 1358 if (super_klass != nullptr && super_klass->should_be_initialized()) { 1359 super_klass->initialize(THREAD); 1360 } 1361 // If C implements any interface that declares a non-static, concrete method, 1362 // the initialization of C triggers initialization of its super interfaces. 1363 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1364 // having a superinterface that declares, non-static, concrete methods 1365 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1366 initialize_super_interfaces(THREAD); 1367 } 1368 1369 // If any exceptions, complete abruptly, throwing the same exception as above. 1370 if (HAS_PENDING_EXCEPTION) { 1371 Handle e(THREAD, PENDING_EXCEPTION); 1372 CLEAR_PENDING_EXCEPTION; 1373 { 1374 EXCEPTION_MARK; 1375 add_initialization_error(THREAD, e); 1376 // Locks object, set state, and notify all waiting threads 1377 set_initialization_state_and_notify(initialization_error, THREAD); 1378 CLEAR_PENDING_EXCEPTION; 1379 } 1380 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1381 THROW_OOP(e()); 1382 } 1383 } 1384 1385 // Step 8 1386 // Initialize classes of inline fields 1387 if (EnableValhalla) { 1388 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1389 if (fs.is_null_free_inline_type()) { 1390 1391 // inline type field klass array entries must have alreadyt been filed at load time or link time 1392 Klass* klass = get_inline_type_field_klass(fs.index()); 1393 1394 InstanceKlass::cast(klass)->initialize(THREAD); 1395 if (fs.access_flags().is_static()) { 1396 if (java_mirror()->obj_field(fs.offset()) == nullptr) { 1397 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value()); 1398 } 1399 } 1400 1401 if (HAS_PENDING_EXCEPTION) { 1402 Handle e(THREAD, PENDING_EXCEPTION); 1403 CLEAR_PENDING_EXCEPTION; 1404 { 1405 EXCEPTION_MARK; 1406 add_initialization_error(THREAD, e); 1407 // Locks object, set state, and notify all waiting threads 1408 set_initialization_state_and_notify(initialization_error, THREAD); 1409 CLEAR_PENDING_EXCEPTION; 1410 } 1411 THROW_OOP(e()); 1412 } 1413 } 1414 } 1415 } 1416 1417 1418 // Step 9 1419 { 1420 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1421 if (class_initializer() != nullptr) { 1422 // Timer includes any side effects of class initialization (resolution, 1423 // etc), but not recursive entry into call_class_initializer(). 1424 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1425 ClassLoader::perf_class_init_selftime(), 1426 ClassLoader::perf_classes_inited(), 1427 jt->get_thread_stat()->perf_recursion_counts_addr(), 1428 jt->get_thread_stat()->perf_timers_addr(), 1429 PerfClassTraceTime::CLASS_CLINIT); 1430 call_class_initializer(THREAD); 1431 } else { 1432 // The elapsed time is so small it's not worth counting. 1433 if (UsePerfData) { 1434 ClassLoader::perf_classes_inited()->inc(); 1435 } 1436 call_class_initializer(THREAD); 1437 } 1438 } 1439 1440 // Step 10 1441 if (!HAS_PENDING_EXCEPTION) { 1442 set_initialization_state_and_notify(fully_initialized, CHECK); 1443 debug_only(vtable().verify(tty, true);) 1444 } 1445 else { 1446 // Step 11 and 12 1447 Handle e(THREAD, PENDING_EXCEPTION); 1448 CLEAR_PENDING_EXCEPTION; 1449 // JVMTI has already reported the pending exception 1450 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1451 JvmtiExport::clear_detected_exception(jt); 1452 { 1453 EXCEPTION_MARK; 1454 add_initialization_error(THREAD, e); 1455 set_initialization_state_and_notify(initialization_error, THREAD); 1456 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1457 // JVMTI has already reported the pending exception 1458 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1459 JvmtiExport::clear_detected_exception(jt); 1460 } 1461 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1462 if (e->is_a(vmClasses::Error_klass())) { 1463 THROW_OOP(e()); 1464 } else { 1465 JavaCallArguments args(e); 1466 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1467 vmSymbols::throwable_void_signature(), 1468 &args); 1469 } 1470 } 1471 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1472 } 1473 1474 1475 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1476 Handle h_init_lock(THREAD, init_lock()); 1477 if (h_init_lock() != nullptr) { 1478 ObjectLocker ol(h_init_lock, THREAD); 1479 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1480 set_init_state(state); 1481 fence_and_clear_init_lock(); 1482 ol.notify_all(CHECK); 1483 } else { 1484 assert(h_init_lock() != nullptr, "The initialization state should never be set twice"); 1485 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1486 set_init_state(state); 1487 } 1488 } 1489 1490 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock 1491 // is grabbed, to ensure that the compiler is not using the class hierarchy. 1492 void InstanceKlass::add_to_hierarchy(JavaThread* current) { 1493 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint"); 1494 1495 DeoptimizationScope deopt_scope; 1496 { 1497 MutexLocker ml(current, Compile_lock); 1498 1499 set_init_state(InstanceKlass::loaded); 1500 // make sure init_state store is already done. 1501 // The compiler reads the hierarchy outside of the Compile_lock. 1502 // Access ordering is used to add to hierarchy. 1503 1504 // Link into hierarchy. 1505 append_to_sibling_list(); // add to superklass/sibling list 1506 process_interfaces(); // handle all "implements" declarations 1507 1508 // Now mark all code that depended on old class hierarchy. 1509 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) 1510 if (Universe::is_fully_initialized()) { 1511 CodeCache::mark_dependents_on(&deopt_scope, this); 1512 } 1513 } 1514 // Perform the deopt handshake outside Compile_lock. 1515 deopt_scope.deoptimize_marked(); 1516 } 1517 1518 1519 InstanceKlass* InstanceKlass::implementor() const { 1520 InstanceKlass* volatile* ik = adr_implementor(); 1521 if (ik == nullptr) { 1522 return nullptr; 1523 } else { 1524 // This load races with inserts, and therefore needs acquire. 1525 InstanceKlass* ikls = Atomic::load_acquire(ik); 1526 if (ikls != nullptr && !ikls->is_loader_alive()) { 1527 return nullptr; // don't return unloaded class 1528 } else { 1529 return ikls; 1530 } 1531 } 1532 } 1533 1534 1535 void InstanceKlass::set_implementor(InstanceKlass* ik) { 1536 assert_locked_or_safepoint(Compile_lock); 1537 assert(is_interface(), "not interface"); 1538 InstanceKlass* volatile* addr = adr_implementor(); 1539 assert(addr != nullptr, "null addr"); 1540 if (addr != nullptr) { 1541 Atomic::release_store(addr, ik); 1542 } 1543 } 1544 1545 int InstanceKlass::nof_implementors() const { 1546 InstanceKlass* ik = implementor(); 1547 if (ik == nullptr) { 1548 return 0; 1549 } else if (ik != this) { 1550 return 1; 1551 } else { 1552 return 2; 1553 } 1554 } 1555 1556 // The embedded _implementor field can only record one implementor. 1557 // When there are more than one implementors, the _implementor field 1558 // is set to the interface Klass* itself. Following are the possible 1559 // values for the _implementor field: 1560 // null - no implementor 1561 // implementor Klass* - one implementor 1562 // self - more than one implementor 1563 // 1564 // The _implementor field only exists for interfaces. 1565 void InstanceKlass::add_implementor(InstanceKlass* ik) { 1566 if (Universe::is_fully_initialized()) { 1567 assert_lock_strong(Compile_lock); 1568 } 1569 assert(is_interface(), "not interface"); 1570 // Filter out my subinterfaces. 1571 // (Note: Interfaces are never on the subklass list.) 1572 if (ik->is_interface()) return; 1573 1574 // Filter out subclasses whose supers already implement me. 1575 // (Note: CHA must walk subclasses of direct implementors 1576 // in order to locate indirect implementors.) 1577 InstanceKlass* super_ik = ik->java_super(); 1578 if (super_ik != nullptr && super_ik->implements_interface(this)) 1579 // We only need to check one immediate superclass, since the 1580 // implements_interface query looks at transitive_interfaces. 1581 // Any supers of the super have the same (or fewer) transitive_interfaces. 1582 return; 1583 1584 InstanceKlass* iklass = implementor(); 1585 if (iklass == nullptr) { 1586 set_implementor(ik); 1587 } else if (iklass != this && iklass != ik) { 1588 // There is already an implementor. Use itself as an indicator of 1589 // more than one implementors. 1590 set_implementor(this); 1591 } 1592 1593 // The implementor also implements the transitive_interfaces 1594 for (int index = 0; index < local_interfaces()->length(); index++) { 1595 local_interfaces()->at(index)->add_implementor(ik); 1596 } 1597 } 1598 1599 void InstanceKlass::init_implementor() { 1600 if (is_interface()) { 1601 set_implementor(nullptr); 1602 } 1603 } 1604 1605 1606 void InstanceKlass::process_interfaces() { 1607 // link this class into the implementors list of every interface it implements 1608 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1609 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1610 InstanceKlass* interf = local_interfaces()->at(i); 1611 assert(interf->is_interface(), "expected interface"); 1612 interf->add_implementor(this); 1613 } 1614 } 1615 1616 bool InstanceKlass::can_be_primary_super_slow() const { 1617 if (is_interface()) 1618 return false; 1619 else 1620 return Klass::can_be_primary_super_slow(); 1621 } 1622 1623 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1624 Array<InstanceKlass*>* transitive_interfaces) { 1625 // The secondaries are the implemented interfaces. 1626 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1627 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1628 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces; 1629 int num_secondaries = num_extra_slots + interfaces->length(); 1630 if (num_secondaries == 0) { 1631 // Must share this for correct bootstrapping! 1632 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap()); 1633 return nullptr; 1634 } else if (num_extra_slots == 0) { 1635 // The secondary super list is exactly the same as the transitive interfaces, so 1636 // let's use it instead of making a copy. 1637 // Redefine classes has to be careful not to delete this! 1638 if (!UseSecondarySupersTable) { 1639 set_secondary_supers(interfaces); 1640 return nullptr; 1641 } else if (num_extra_slots == 0 && interfaces->length() <= 1) { 1642 // We will reuse the transitive interfaces list if we're certain 1643 // it's in hash order. 1644 uintx bitmap = compute_secondary_supers_bitmap(interfaces); 1645 set_secondary_supers(interfaces, bitmap); 1646 return nullptr; 1647 } 1648 // ... fall through if that didn't work. 1649 } 1650 // Copy transitive interfaces to a temporary growable array to be constructed 1651 // into the secondary super list with extra slots. 1652 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1653 for (int i = 0; i < interfaces->length(); i++) { 1654 secondaries->push(interfaces->at(i)); 1655 } 1656 return secondaries; 1657 } 1658 1659 bool InstanceKlass::implements_interface(Klass* k) const { 1660 if (this == k) return true; 1661 assert(k->is_interface(), "should be an interface class"); 1662 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1663 if (transitive_interfaces()->at(i) == k) { 1664 return true; 1665 } 1666 } 1667 return false; 1668 } 1669 1670 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1671 // Verify direct super interface 1672 if (this == k) return true; 1673 assert(k->is_interface(), "should be an interface class"); 1674 for (int i = 0; i < local_interfaces()->length(); i++) { 1675 if (local_interfaces()->at(i) == k) { 1676 return true; 1677 } 1678 } 1679 return false; 1680 } 1681 1682 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1683 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1684 size_t size = objArrayOopDesc::object_size(length); 1685 ArrayKlass* ak = array_klass(n, CHECK_NULL); 1686 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1687 /* do_zero */ true, CHECK_NULL); 1688 return o; 1689 } 1690 1691 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1692 if (TraceFinalizerRegistration) { 1693 tty->print("Registered "); 1694 i->print_value_on(tty); 1695 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i)); 1696 } 1697 instanceHandle h_i(THREAD, i); 1698 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1699 JavaValue result(T_VOID); 1700 JavaCallArguments args(h_i); 1701 methodHandle mh(THREAD, Universe::finalizer_register_method()); 1702 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1703 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);) 1704 return h_i(); 1705 } 1706 1707 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1708 assert(!is_abstract() && !is_interface(), "Should not create this object"); 1709 size_t size = size_helper(); // Query before forming handle. 1710 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1711 } 1712 1713 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) { 1714 Klass* k = java_lang_Class::as_Klass(java_class); 1715 if (k == nullptr) { 1716 ResourceMark rm(THREAD); 1717 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr); 1718 } 1719 InstanceKlass* ik = cast(k); 1720 ik->check_valid_for_instantiation(false, CHECK_NULL); 1721 ik->initialize(CHECK_NULL); 1722 return ik->allocate_instance(THREAD); 1723 } 1724 1725 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1726 return instanceHandle(THREAD, allocate_instance(THREAD)); 1727 } 1728 1729 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1730 if (is_interface() || is_abstract()) { 1731 ResourceMark rm(THREAD); 1732 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1733 : vmSymbols::java_lang_InstantiationException(), external_name()); 1734 } 1735 if (this == vmClasses::Class_klass()) { 1736 ResourceMark rm(THREAD); 1737 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1738 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1739 } 1740 } 1741 1742 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) { 1743 // Need load-acquire for lock-free read 1744 if (array_klasses_acquire() == nullptr) { 1745 1746 // Recursively lock array allocation 1747 RecursiveLocker rl(MultiArray_lock, THREAD); 1748 1749 // Check if another thread created the array klass while we were waiting for the lock. 1750 if (array_klasses() == nullptr) { 1751 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, false, CHECK_NULL); 1752 // use 'release' to pair with lock-free load 1753 release_set_array_klasses(k); 1754 } 1755 } 1756 1757 // array_klasses() will always be set at this point 1758 ArrayKlass* ak = array_klasses(); 1759 assert(ak != nullptr, "should be set"); 1760 return ak->array_klass(n, THREAD); 1761 } 1762 1763 ArrayKlass* InstanceKlass::array_klass_or_null(int n) { 1764 // Need load-acquire for lock-free read 1765 ArrayKlass* ak = array_klasses_acquire(); 1766 if (ak == nullptr) { 1767 return nullptr; 1768 } else { 1769 return ak->array_klass_or_null(n); 1770 } 1771 } 1772 1773 ArrayKlass* InstanceKlass::array_klass(TRAPS) { 1774 return array_klass(1, THREAD); 1775 } 1776 1777 ArrayKlass* InstanceKlass::array_klass_or_null() { 1778 return array_klass_or_null(1); 1779 } 1780 1781 static int call_class_initializer_counter = 0; // for debugging 1782 1783 Method* InstanceKlass::class_initializer() const { 1784 Method* clinit = find_method( 1785 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1786 if (clinit != nullptr && clinit->is_class_initializer()) { 1787 return clinit; 1788 } 1789 return nullptr; 1790 } 1791 1792 void InstanceKlass::call_class_initializer(TRAPS) { 1793 if (ReplayCompiles && 1794 (ReplaySuppressInitializers == 1 || 1795 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) { 1796 // Hide the existence of the initializer for the purpose of replaying the compile 1797 return; 1798 } 1799 1800 #if INCLUDE_CDS 1801 // This is needed to ensure the consistency of the archived heap objects. 1802 if (has_archived_enum_objs()) { 1803 assert(is_shared(), "must be"); 1804 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK); 1805 if (initialized) { 1806 return; 1807 } 1808 } 1809 #endif 1810 1811 methodHandle h_method(THREAD, class_initializer()); 1812 assert(!is_initialized(), "we cannot initialize twice"); 1813 LogTarget(Info, class, init) lt; 1814 if (lt.is_enabled()) { 1815 ResourceMark rm(THREAD); 1816 LogStream ls(lt); 1817 ls.print("%d Initializing ", call_class_initializer_counter++); 1818 name()->print_value_on(&ls); 1819 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"", 1820 h_method() == nullptr ? "(no method)" : "", p2i(this), 1821 THREAD->name()); 1822 } 1823 if (h_method() != nullptr) { 1824 JavaCallArguments args; // No arguments 1825 JavaValue result(T_VOID); 1826 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1827 } 1828 } 1829 1830 1831 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1832 InterpreterOopMap* entry_for) { 1833 // Lazily create the _oop_map_cache at first request. 1834 // Load_acquire is needed to safely get instance published with CAS by another thread. 1835 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1836 if (oop_map_cache == nullptr) { 1837 // Try to install new instance atomically. 1838 oop_map_cache = new OopMapCache(); 1839 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache); 1840 if (other != nullptr) { 1841 // Someone else managed to install before us, ditch local copy and use the existing one. 1842 delete oop_map_cache; 1843 oop_map_cache = other; 1844 } 1845 } 1846 // _oop_map_cache is constant after init; lookup below does its own locking. 1847 oop_map_cache->lookup(method, bci, entry_for); 1848 } 1849 1850 1851 FieldInfo InstanceKlass::field(int index) const { 1852 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1853 if (fs.index() == index) { 1854 return fs.to_FieldInfo(); 1855 } 1856 } 1857 fatal("Field not found"); 1858 return FieldInfo(); 1859 } 1860 1861 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1862 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1863 Symbol* f_name = fs.name(); 1864 Symbol* f_sig = fs.signature(); 1865 if (f_name == name && f_sig == sig) { 1866 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1867 return true; 1868 } 1869 } 1870 return false; 1871 } 1872 1873 1874 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1875 const int n = local_interfaces()->length(); 1876 for (int i = 0; i < n; i++) { 1877 Klass* intf1 = local_interfaces()->at(i); 1878 assert(intf1->is_interface(), "just checking type"); 1879 // search for field in current interface 1880 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1881 assert(fd->is_static(), "interface field must be static"); 1882 return intf1; 1883 } 1884 // search for field in direct superinterfaces 1885 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1886 if (intf2 != nullptr) return intf2; 1887 } 1888 // otherwise field lookup fails 1889 return nullptr; 1890 } 1891 1892 1893 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1894 // search order according to newest JVM spec (5.4.3.2, p.167). 1895 // 1) search for field in current klass 1896 if (find_local_field(name, sig, fd)) { 1897 return const_cast<InstanceKlass*>(this); 1898 } 1899 // 2) search for field recursively in direct superinterfaces 1900 { Klass* intf = find_interface_field(name, sig, fd); 1901 if (intf != nullptr) return intf; 1902 } 1903 // 3) apply field lookup recursively if superclass exists 1904 { Klass* supr = super(); 1905 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1906 } 1907 // 4) otherwise field lookup fails 1908 return nullptr; 1909 } 1910 1911 1912 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1913 // search order according to newest JVM spec (5.4.3.2, p.167). 1914 // 1) search for field in current klass 1915 if (find_local_field(name, sig, fd)) { 1916 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1917 } 1918 // 2) search for field recursively in direct superinterfaces 1919 if (is_static) { 1920 Klass* intf = find_interface_field(name, sig, fd); 1921 if (intf != nullptr) return intf; 1922 } 1923 // 3) apply field lookup recursively if superclass exists 1924 { Klass* supr = super(); 1925 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1926 } 1927 // 4) otherwise field lookup fails 1928 return nullptr; 1929 } 1930 1931 bool InstanceKlass::contains_field_offset(int offset) { 1932 if (this->is_inline_klass()) { 1933 InlineKlass* vk = InlineKlass::cast(this); 1934 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->get_payload_size_in_bytes()); 1935 } else { 1936 fieldDescriptor fd; 1937 return find_field_from_offset(offset, false, &fd); 1938 } 1939 } 1940 1941 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1942 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1943 if (fs.offset() == offset) { 1944 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1945 if (fd->is_static() == is_static) return true; 1946 } 1947 } 1948 return false; 1949 } 1950 1951 1952 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1953 Klass* klass = const_cast<InstanceKlass*>(this); 1954 while (klass != nullptr) { 1955 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1956 return true; 1957 } 1958 klass = klass->super(); 1959 } 1960 return false; 1961 } 1962 1963 1964 void InstanceKlass::methods_do(void f(Method* method)) { 1965 // Methods aren't stable until they are loaded. This can be read outside 1966 // a lock through the ClassLoaderData for profiling 1967 // Redefined scratch classes are on the list and need to be cleaned 1968 if (!is_loaded() && !is_scratch_class()) { 1969 return; 1970 } 1971 1972 int len = methods()->length(); 1973 for (int index = 0; index < len; index++) { 1974 Method* m = methods()->at(index); 1975 assert(m->is_method(), "must be method"); 1976 f(m); 1977 } 1978 } 1979 1980 1981 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1982 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1983 if (fs.access_flags().is_static()) { 1984 fieldDescriptor& fd = fs.field_descriptor(); 1985 cl->do_field(&fd); 1986 } 1987 } 1988 } 1989 1990 1991 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1992 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1993 if (fs.access_flags().is_static()) { 1994 fieldDescriptor& fd = fs.field_descriptor(); 1995 f(&fd, mirror, CHECK); 1996 } 1997 } 1998 } 1999 2000 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 2001 InstanceKlass* super = superklass(); 2002 if (super != nullptr) { 2003 super->do_nonstatic_fields(cl); 2004 } 2005 fieldDescriptor fd; 2006 int length = java_fields_count(); 2007 for (int i = 0; i < length; i += 1) { 2008 fd.reinitialize(this, i); 2009 if (!fd.is_static()) { 2010 cl->do_field(&fd); 2011 } 2012 } 2013 } 2014 2015 // first in Pair is offset, second is index. 2016 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) { 2017 return a->first - b->first; 2018 } 2019 2020 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) { 2021 InstanceKlass* super = superklass(); 2022 if (super != nullptr) { 2023 super->print_nonstatic_fields(cl); 2024 } 2025 ResourceMark rm; 2026 fieldDescriptor fd; 2027 // In DebugInfo nonstatic fields are sorted by offset. 2028 GrowableArray<Pair<int,int> > fields_sorted; 2029 int i = 0; 2030 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 2031 if (!fs.access_flags().is_static()) { 2032 fd = fs.field_descriptor(); 2033 Pair<int,int> f(fs.offset(), fs.index()); 2034 fields_sorted.push(f); 2035 i++; 2036 } 2037 } 2038 if (i > 0) { 2039 int length = i; 2040 assert(length == fields_sorted.length(), "duh"); 2041 fields_sorted.sort(compare_fields_by_offset); 2042 for (int i = 0; i < length; i++) { 2043 fd.reinitialize(this, fields_sorted.at(i).second); 2044 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields"); 2045 cl->do_field(&fd); 2046 } 2047 } 2048 } 2049 2050 #ifdef ASSERT 2051 static int linear_search(const Array<Method*>* methods, 2052 const Symbol* name, 2053 const Symbol* signature) { 2054 const int len = methods->length(); 2055 for (int index = 0; index < len; index++) { 2056 const Method* const m = methods->at(index); 2057 assert(m->is_method(), "must be method"); 2058 if (m->signature() == signature && m->name() == name) { 2059 return index; 2060 } 2061 } 2062 return -1; 2063 } 2064 #endif 2065 2066 bool InstanceKlass::_disable_method_binary_search = false; 2067 2068 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 2069 int len = methods->length(); 2070 int l = 0; 2071 int h = len - 1; 2072 while (l <= h) { 2073 Method* m = methods->at(l); 2074 if (m->name() == name) { 2075 return l; 2076 } 2077 l++; 2078 } 2079 return -1; 2080 } 2081 2082 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 2083 if (_disable_method_binary_search) { 2084 assert(CDSConfig::is_dumping_dynamic_archive(), "must be"); 2085 // At the final stage of dynamic dumping, the methods array may not be sorted 2086 // by ascending addresses of their names, so we can't use binary search anymore. 2087 // However, methods with the same name are still laid out consecutively inside the 2088 // methods array, so let's look for the first one that matches. 2089 return linear_search(methods, name); 2090 } 2091 2092 int len = methods->length(); 2093 int l = 0; 2094 int h = len - 1; 2095 2096 // methods are sorted by ascending addresses of their names, so do binary search 2097 while (l <= h) { 2098 int mid = (l + h) >> 1; 2099 Method* m = methods->at(mid); 2100 assert(m->is_method(), "must be method"); 2101 int res = m->name()->fast_compare(name); 2102 if (res == 0) { 2103 return mid; 2104 } else if (res < 0) { 2105 l = mid + 1; 2106 } else { 2107 h = mid - 1; 2108 } 2109 } 2110 return -1; 2111 } 2112 2113 // find_method looks up the name/signature in the local methods array 2114 Method* InstanceKlass::find_method(const Symbol* name, 2115 const Symbol* signature) const { 2116 return find_method_impl(name, signature, 2117 OverpassLookupMode::find, 2118 StaticLookupMode::find, 2119 PrivateLookupMode::find); 2120 } 2121 2122 Method* InstanceKlass::find_method_impl(const Symbol* name, 2123 const Symbol* signature, 2124 OverpassLookupMode overpass_mode, 2125 StaticLookupMode static_mode, 2126 PrivateLookupMode private_mode) const { 2127 return InstanceKlass::find_method_impl(methods(), 2128 name, 2129 signature, 2130 overpass_mode, 2131 static_mode, 2132 private_mode); 2133 } 2134 2135 // find_instance_method looks up the name/signature in the local methods array 2136 // and skips over static methods 2137 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 2138 const Symbol* name, 2139 const Symbol* signature, 2140 PrivateLookupMode private_mode) { 2141 Method* const meth = InstanceKlass::find_method_impl(methods, 2142 name, 2143 signature, 2144 OverpassLookupMode::find, 2145 StaticLookupMode::skip, 2146 private_mode); 2147 assert(((meth == nullptr) || !meth->is_static()), 2148 "find_instance_method should have skipped statics"); 2149 return meth; 2150 } 2151 2152 // find_instance_method looks up the name/signature in the local methods array 2153 // and skips over static methods 2154 Method* InstanceKlass::find_instance_method(const Symbol* name, 2155 const Symbol* signature, 2156 PrivateLookupMode private_mode) const { 2157 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 2158 } 2159 2160 // Find looks up the name/signature in the local methods array 2161 // and filters on the overpass, static and private flags 2162 // This returns the first one found 2163 // note that the local methods array can have up to one overpass, one static 2164 // and one instance (private or not) with the same name/signature 2165 Method* InstanceKlass::find_local_method(const Symbol* name, 2166 const Symbol* signature, 2167 OverpassLookupMode overpass_mode, 2168 StaticLookupMode static_mode, 2169 PrivateLookupMode private_mode) const { 2170 return InstanceKlass::find_method_impl(methods(), 2171 name, 2172 signature, 2173 overpass_mode, 2174 static_mode, 2175 private_mode); 2176 } 2177 2178 // Find looks up the name/signature in the local methods array 2179 // and filters on the overpass, static and private flags 2180 // This returns the first one found 2181 // note that the local methods array can have up to one overpass, one static 2182 // and one instance (private or not) with the same name/signature 2183 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 2184 const Symbol* name, 2185 const Symbol* signature, 2186 OverpassLookupMode overpass_mode, 2187 StaticLookupMode static_mode, 2188 PrivateLookupMode private_mode) { 2189 return InstanceKlass::find_method_impl(methods, 2190 name, 2191 signature, 2192 overpass_mode, 2193 static_mode, 2194 private_mode); 2195 } 2196 2197 Method* InstanceKlass::find_method(const Array<Method*>* methods, 2198 const Symbol* name, 2199 const Symbol* signature) { 2200 return InstanceKlass::find_method_impl(methods, 2201 name, 2202 signature, 2203 OverpassLookupMode::find, 2204 StaticLookupMode::find, 2205 PrivateLookupMode::find); 2206 } 2207 2208 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 2209 const Symbol* name, 2210 const Symbol* signature, 2211 OverpassLookupMode overpass_mode, 2212 StaticLookupMode static_mode, 2213 PrivateLookupMode private_mode) { 2214 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 2215 return hit >= 0 ? methods->at(hit): nullptr; 2216 } 2217 2218 // true if method matches signature and conforms to skipping_X conditions. 2219 static bool method_matches(const Method* m, 2220 const Symbol* signature, 2221 bool skipping_overpass, 2222 bool skipping_static, 2223 bool skipping_private) { 2224 return ((m->signature() == signature) && 2225 (!skipping_overpass || !m->is_overpass()) && 2226 (!skipping_static || !m->is_static()) && 2227 (!skipping_private || !m->is_private())); 2228 } 2229 2230 // Used directly for default_methods to find the index into the 2231 // default_vtable_indices, and indirectly by find_method 2232 // find_method_index looks in the local methods array to return the index 2233 // of the matching name/signature. If, overpass methods are being ignored, 2234 // the search continues to find a potential non-overpass match. This capability 2235 // is important during method resolution to prefer a static method, for example, 2236 // over an overpass method. 2237 // There is the possibility in any _method's array to have the same name/signature 2238 // for a static method, an overpass method and a local instance method 2239 // To correctly catch a given method, the search criteria may need 2240 // to explicitly skip the other two. For local instance methods, it 2241 // is often necessary to skip private methods 2242 int InstanceKlass::find_method_index(const Array<Method*>* methods, 2243 const Symbol* name, 2244 const Symbol* signature, 2245 OverpassLookupMode overpass_mode, 2246 StaticLookupMode static_mode, 2247 PrivateLookupMode private_mode) { 2248 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip); 2249 const bool skipping_static = (static_mode == StaticLookupMode::skip); 2250 const bool skipping_private = (private_mode == PrivateLookupMode::skip); 2251 const int hit = quick_search(methods, name); 2252 if (hit != -1) { 2253 const Method* const m = methods->at(hit); 2254 2255 // Do linear search to find matching signature. First, quick check 2256 // for common case, ignoring overpasses if requested. 2257 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2258 return hit; 2259 } 2260 2261 // search downwards through overloaded methods 2262 int i; 2263 for (i = hit - 1; i >= 0; --i) { 2264 const Method* const m = methods->at(i); 2265 assert(m->is_method(), "must be method"); 2266 if (m->name() != name) { 2267 break; 2268 } 2269 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2270 return i; 2271 } 2272 } 2273 // search upwards 2274 for (i = hit + 1; i < methods->length(); ++i) { 2275 const Method* const m = methods->at(i); 2276 assert(m->is_method(), "must be method"); 2277 if (m->name() != name) { 2278 break; 2279 } 2280 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2281 return i; 2282 } 2283 } 2284 // not found 2285 #ifdef ASSERT 2286 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 2287 linear_search(methods, name, signature); 2288 assert(-1 == index, "binary search should have found entry %d", index); 2289 #endif 2290 } 2291 return -1; 2292 } 2293 2294 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 2295 return find_method_by_name(methods(), name, end); 2296 } 2297 2298 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 2299 const Symbol* name, 2300 int* end_ptr) { 2301 assert(end_ptr != nullptr, "just checking"); 2302 int start = quick_search(methods, name); 2303 int end = start + 1; 2304 if (start != -1) { 2305 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 2306 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 2307 *end_ptr = end; 2308 return start; 2309 } 2310 return -1; 2311 } 2312 2313 // uncached_lookup_method searches both the local class methods array and all 2314 // superclasses methods arrays, skipping any overpass methods in superclasses, 2315 // and possibly skipping private methods. 2316 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 2317 const Symbol* signature, 2318 OverpassLookupMode overpass_mode, 2319 PrivateLookupMode private_mode) const { 2320 OverpassLookupMode overpass_local_mode = overpass_mode; 2321 const Klass* klass = this; 2322 while (klass != nullptr) { 2323 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 2324 signature, 2325 overpass_local_mode, 2326 StaticLookupMode::find, 2327 private_mode); 2328 if (method != nullptr) { 2329 return method; 2330 } 2331 if (name == vmSymbols::object_initializer_name()) { 2332 break; // <init> is never inherited 2333 } 2334 klass = klass->super(); 2335 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses 2336 } 2337 return nullptr; 2338 } 2339 2340 #ifdef ASSERT 2341 // search through class hierarchy and return true if this class or 2342 // one of the superclasses was redefined 2343 bool InstanceKlass::has_redefined_this_or_super() const { 2344 const Klass* klass = this; 2345 while (klass != nullptr) { 2346 if (InstanceKlass::cast(klass)->has_been_redefined()) { 2347 return true; 2348 } 2349 klass = klass->super(); 2350 } 2351 return false; 2352 } 2353 #endif 2354 2355 // lookup a method in the default methods list then in all transitive interfaces 2356 // Do NOT return private or static methods 2357 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 2358 Symbol* signature) const { 2359 Method* m = nullptr; 2360 if (default_methods() != nullptr) { 2361 m = find_method(default_methods(), name, signature); 2362 } 2363 // Look up interfaces 2364 if (m == nullptr) { 2365 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find); 2366 } 2367 return m; 2368 } 2369 2370 // lookup a method in all the interfaces that this class implements 2371 // Do NOT return private or static methods, new in JDK8 which are not externally visible 2372 // They should only be found in the initial InterfaceMethodRef 2373 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 2374 Symbol* signature, 2375 DefaultsLookupMode defaults_mode) const { 2376 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 2377 int num_ifs = all_ifs->length(); 2378 InstanceKlass *ik = nullptr; 2379 for (int i = 0; i < num_ifs; i++) { 2380 ik = all_ifs->at(i); 2381 Method* m = ik->lookup_method(name, signature); 2382 if (m != nullptr && m->is_public() && !m->is_static() && 2383 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) { 2384 return m; 2385 } 2386 } 2387 return nullptr; 2388 } 2389 2390 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose) 2391 :_st(st), _verbose(verbose) { 2392 ResourceMark rm; 2393 _st->print("%-18s ", "KlassAddr"); 2394 _st->print("%-4s ", "Size"); 2395 _st->print("%-20s ", "State"); 2396 _st->print("%-7s ", "Flags"); 2397 _st->print("%-5s ", "ClassName"); 2398 _st->cr(); 2399 } 2400 2401 void PrintClassClosure::do_klass(Klass* k) { 2402 ResourceMark rm; 2403 // klass pointer 2404 _st->print(PTR_FORMAT " ", p2i(k)); 2405 // klass size 2406 _st->print("%4d ", k->size()); 2407 // initialization state 2408 if (k->is_instance_klass()) { 2409 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name()); 2410 } else { 2411 _st->print("%-20s ",""); 2412 } 2413 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc) 2414 char buf[10]; 2415 int i = 0; 2416 if (k->has_finalizer()) buf[i++] = 'F'; 2417 if (k->is_instance_klass()) { 2418 InstanceKlass* ik = InstanceKlass::cast(k); 2419 if (ik->has_final_method()) buf[i++] = 'f'; 2420 if (ik->is_rewritten()) buf[i++] = 'W'; 2421 if (ik->is_contended()) buf[i++] = 'C'; 2422 if (ik->has_been_redefined()) buf[i++] = 'R'; 2423 if (ik->is_shared()) buf[i++] = 'S'; 2424 } 2425 buf[i++] = '\0'; 2426 _st->print("%-7s ", buf); 2427 // klass name 2428 _st->print("%-5s ", k->external_name()); 2429 // end 2430 _st->cr(); 2431 if (_verbose) { 2432 k->print_on(_st); 2433 } 2434 } 2435 2436 /* jni_id_for for jfieldIds only */ 2437 JNIid* InstanceKlass::jni_id_for(int offset) { 2438 MutexLocker ml(JfieldIdCreation_lock); 2439 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset); 2440 if (probe == nullptr) { 2441 // Allocate new static field identifier 2442 probe = new JNIid(this, offset, jni_ids()); 2443 set_jni_ids(probe); 2444 } 2445 return probe; 2446 } 2447 2448 u2 InstanceKlass::enclosing_method_data(int offset) const { 2449 const Array<jushort>* const inner_class_list = inner_classes(); 2450 if (inner_class_list == nullptr) { 2451 return 0; 2452 } 2453 const int length = inner_class_list->length(); 2454 if (length % inner_class_next_offset == 0) { 2455 return 0; 2456 } 2457 const int index = length - enclosing_method_attribute_size; 2458 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2459 return inner_class_list->at(index + offset); 2460 } 2461 2462 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2463 u2 method_index) { 2464 Array<jushort>* inner_class_list = inner_classes(); 2465 assert (inner_class_list != nullptr, "_inner_classes list is not set up"); 2466 int length = inner_class_list->length(); 2467 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2468 int index = length - enclosing_method_attribute_size; 2469 inner_class_list->at_put( 2470 index + enclosing_method_class_index_offset, class_index); 2471 inner_class_list->at_put( 2472 index + enclosing_method_method_index_offset, method_index); 2473 } 2474 } 2475 2476 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) { 2477 if (method->is_old() && !method->is_obsolete()) { 2478 // If the method passed in is old (but not obsolete), use the current version. 2479 method = method_with_idnum((int)idnum); 2480 assert(method != nullptr, "old and but not obsolete, so should exist"); 2481 } 2482 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method); 2483 Atomic::release_store(&jmeths[idnum + 1], new_id); 2484 return new_id; 2485 } 2486 2487 // Lookup or create a jmethodID. 2488 // This code is called by the VMThread and JavaThreads so the 2489 // locking has to be done very carefully to avoid deadlocks 2490 // and/or other cache consistency problems. 2491 // 2492 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 2493 Method* method = method_h(); 2494 int idnum = method->method_idnum(); 2495 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2496 2497 // We use a double-check locking idiom here because this cache is 2498 // performance sensitive. In the normal system, this cache only 2499 // transitions from null to non-null which is safe because we use 2500 // release_set_methods_jmethod_ids() to advertise the new cache. 2501 // A partially constructed cache should never be seen by a racing 2502 // thread. We also use release_store() to save a new jmethodID 2503 // in the cache so a partially constructed jmethodID should never be 2504 // seen either. Cache reads of existing jmethodIDs proceed without a 2505 // lock, but cache writes of a new jmethodID requires uniqueness and 2506 // creation of the cache itself requires no leaks so a lock is 2507 // acquired in those two cases. 2508 // 2509 // If the RedefineClasses() API has been used, then this cache grows 2510 // in the redefinition safepoint. 2511 2512 if (jmeths == nullptr) { 2513 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2514 jmeths = methods_jmethod_ids_acquire(); 2515 // Still null? 2516 if (jmeths == nullptr) { 2517 size_t size = idnum_allocated_count(); 2518 assert(size > (size_t)idnum, "should already have space"); 2519 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2520 memset(jmeths, 0, (size + 1) * sizeof(jmethodID)); 2521 // cache size is stored in element[0], other elements offset by one 2522 jmeths[0] = (jmethodID)size; 2523 jmethodID new_id = update_jmethod_id(jmeths, method, idnum); 2524 2525 // publish jmeths 2526 release_set_methods_jmethod_ids(jmeths); 2527 return new_id; 2528 } 2529 } 2530 2531 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]); 2532 if (id == nullptr) { 2533 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2534 id = jmeths[idnum + 1]; 2535 // Still null? 2536 if (id == nullptr) { 2537 return update_jmethod_id(jmeths, method, idnum); 2538 } 2539 } 2540 return id; 2541 } 2542 2543 void InstanceKlass::update_methods_jmethod_cache() { 2544 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2545 jmethodID* cache = _methods_jmethod_ids; 2546 if (cache != nullptr) { 2547 size_t size = idnum_allocated_count(); 2548 size_t old_size = (size_t)cache[0]; 2549 if (old_size < size + 1) { 2550 // Allocate a larger one and copy entries to the new one. 2551 // They've already been updated to point to new methods where applicable (i.e., not obsolete). 2552 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2553 memset(new_cache, 0, (size + 1) * sizeof(jmethodID)); 2554 // The cache size is stored in element[0]; the other elements are offset by one. 2555 new_cache[0] = (jmethodID)size; 2556 2557 for (int i = 1; i <= (int)old_size; i++) { 2558 new_cache[i] = cache[i]; 2559 } 2560 _methods_jmethod_ids = new_cache; 2561 FREE_C_HEAP_ARRAY(jmethodID, cache); 2562 } 2563 } 2564 } 2565 2566 // Figure out how many jmethodIDs haven't been allocated, and make 2567 // sure space for them is pre-allocated. This makes getting all 2568 // method ids much, much faster with classes with more than 8 2569 // methods, and has a *substantial* effect on performance with jvmti 2570 // code that loads all jmethodIDs for all classes. 2571 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 2572 int new_jmeths = 0; 2573 int length = methods()->length(); 2574 for (int index = start_offset; index < length; index++) { 2575 Method* m = methods()->at(index); 2576 jmethodID id = m->find_jmethod_id_or_null(); 2577 if (id == nullptr) { 2578 new_jmeths++; 2579 } 2580 } 2581 if (new_jmeths != 0) { 2582 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 2583 } 2584 } 2585 2586 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles 2587 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2588 int idnum = method->method_idnum(); 2589 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2590 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr; 2591 } 2592 2593 inline DependencyContext InstanceKlass::dependencies() { 2594 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2595 return dep_context; 2596 } 2597 2598 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) { 2599 dependencies().mark_dependent_nmethods(deopt_scope, changes); 2600 } 2601 2602 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2603 dependencies().add_dependent_nmethod(nm); 2604 } 2605 2606 void InstanceKlass::clean_dependency_context() { 2607 dependencies().clean_unloading_dependents(); 2608 } 2609 2610 #ifndef PRODUCT 2611 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2612 dependencies().print_dependent_nmethods(verbose); 2613 } 2614 2615 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2616 return dependencies().is_dependent_nmethod(nm); 2617 } 2618 #endif //PRODUCT 2619 2620 void InstanceKlass::clean_weak_instanceklass_links() { 2621 clean_implementors_list(); 2622 clean_method_data(); 2623 } 2624 2625 void InstanceKlass::clean_implementors_list() { 2626 assert(is_loader_alive(), "this klass should be live"); 2627 if (is_interface()) { 2628 assert (ClassUnloading, "only called for ClassUnloading"); 2629 for (;;) { 2630 // Use load_acquire due to competing with inserts 2631 InstanceKlass* volatile* iklass = adr_implementor(); 2632 assert(iklass != nullptr, "Klass must not be null"); 2633 InstanceKlass* impl = Atomic::load_acquire(iklass); 2634 if (impl != nullptr && !impl->is_loader_alive()) { 2635 // null this field, might be an unloaded instance klass or null 2636 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) { 2637 // Successfully unlinking implementor. 2638 if (log_is_enabled(Trace, class, unload)) { 2639 ResourceMark rm; 2640 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2641 } 2642 return; 2643 } 2644 } else { 2645 return; 2646 } 2647 } 2648 } 2649 } 2650 2651 void InstanceKlass::clean_method_data() { 2652 for (int m = 0; m < methods()->length(); m++) { 2653 MethodData* mdo = methods()->at(m)->method_data(); 2654 if (mdo != nullptr) { 2655 mdo->clean_method_data(/*always_clean*/false); 2656 } 2657 } 2658 } 2659 2660 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2661 Klass::metaspace_pointers_do(it); 2662 2663 if (log_is_enabled(Trace, cds)) { 2664 ResourceMark rm; 2665 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2666 } 2667 2668 it->push(&_annotations); 2669 it->push((Klass**)&_array_klasses); 2670 if (!is_rewritten()) { 2671 it->push(&_constants, MetaspaceClosure::_writable); 2672 } else { 2673 it->push(&_constants); 2674 } 2675 it->push(&_inner_classes); 2676 #if INCLUDE_JVMTI 2677 it->push(&_previous_versions); 2678 #endif 2679 #if INCLUDE_CDS 2680 // For "old" classes with methods containing the jsr bytecode, the _methods array will 2681 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to 2682 // be writable. The length check on the _methods is necessary because classes which 2683 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region. 2684 if (_methods != nullptr && _methods->length() > 0 && 2685 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) { 2686 // To handle jsr bytecode, new Method* maybe stored into _methods 2687 it->push(&_methods, MetaspaceClosure::_writable); 2688 } else { 2689 #endif 2690 it->push(&_methods); 2691 #if INCLUDE_CDS 2692 } 2693 #endif 2694 it->push(&_default_methods); 2695 it->push(&_local_interfaces); 2696 it->push(&_transitive_interfaces); 2697 it->push(&_method_ordering); 2698 if (!is_rewritten()) { 2699 it->push(&_default_vtable_indices, MetaspaceClosure::_writable); 2700 } else { 2701 it->push(&_default_vtable_indices); 2702 } 2703 2704 it->push(&_fieldinfo_stream); 2705 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update() 2706 it->push(&_fields_status, MetaspaceClosure::_writable); 2707 2708 if (itable_length() > 0) { 2709 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2710 int method_table_offset_in_words = ioe->offset()/wordSize; 2711 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this); 2712 2713 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words) 2714 / itableOffsetEntry::size(); 2715 2716 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2717 if (ioe->interface_klass() != nullptr) { 2718 it->push(ioe->interface_klass_addr()); 2719 itableMethodEntry* ime = ioe->first_method_entry(this); 2720 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2721 for (int index = 0; index < n; index ++) { 2722 it->push(ime[index].method_addr()); 2723 } 2724 } 2725 } 2726 } 2727 2728 it->push(&_nest_members); 2729 it->push(&_permitted_subclasses); 2730 it->push(&_loadable_descriptors); 2731 it->push(&_record_components); 2732 2733 it->push(&_inline_type_field_klasses, MetaspaceClosure::_writable); 2734 it->push(&_null_marker_offsets); 2735 } 2736 2737 #if INCLUDE_CDS 2738 void InstanceKlass::remove_unshareable_info() { 2739 2740 if (is_linked()) { 2741 assert(can_be_verified_at_dumptime(), "must be"); 2742 // Remember this so we can avoid walking the hierarchy at runtime. 2743 set_verified_at_dump_time(); 2744 } 2745 2746 Klass::remove_unshareable_info(); 2747 2748 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2749 // Classes are attempted to link during dumping and may fail, 2750 // but these classes are still in the dictionary and class list in CLD. 2751 // If the class has failed verification, there is nothing else to remove. 2752 return; 2753 } 2754 2755 // Reset to the 'allocated' state to prevent any premature accessing to 2756 // a shared class at runtime while the class is still being loaded and 2757 // restored. A class' init_state is set to 'loaded' at runtime when it's 2758 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()). 2759 _init_state = allocated; 2760 2761 { // Otherwise this needs to take out the Compile_lock. 2762 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2763 init_implementor(); 2764 } 2765 2766 // Call remove_unshareable_info() on other objects that belong to this class, except 2767 // for constants()->remove_unshareable_info(), which is called in a separate pass in 2768 // ArchiveBuilder::make_klasses_shareable(), 2769 2770 for (int i = 0; i < methods()->length(); i++) { 2771 Method* m = methods()->at(i); 2772 m->remove_unshareable_info(); 2773 } 2774 2775 // do array classes also. 2776 if (array_klasses() != nullptr) { 2777 array_klasses()->remove_unshareable_info(); 2778 } 2779 2780 // These are not allocated from metaspace. They are safe to set to nullptr. 2781 _source_debug_extension = nullptr; 2782 _dep_context = nullptr; 2783 _osr_nmethods_head = nullptr; 2784 #if INCLUDE_JVMTI 2785 _breakpoints = nullptr; 2786 _previous_versions = nullptr; 2787 _cached_class_file = nullptr; 2788 _jvmti_cached_class_field_map = nullptr; 2789 #endif 2790 2791 _init_thread = nullptr; 2792 _methods_jmethod_ids = nullptr; 2793 _jni_ids = nullptr; 2794 _oop_map_cache = nullptr; 2795 // clear _nest_host to ensure re-load at runtime 2796 _nest_host = nullptr; 2797 init_shared_package_entry(); 2798 _dep_context_last_cleaned = 0; 2799 2800 remove_unshareable_flags(); 2801 } 2802 2803 void InstanceKlass::remove_unshareable_flags() { 2804 // clear all the flags/stats that shouldn't be in the archived version 2805 assert(!is_scratch_class(), "must be"); 2806 assert(!has_been_redefined(), "must be"); 2807 #if INCLUDE_JVMTI 2808 set_is_being_redefined(false); 2809 #endif 2810 set_has_resolved_methods(false); 2811 } 2812 2813 void InstanceKlass::remove_java_mirror() { 2814 Klass::remove_java_mirror(); 2815 2816 // do array classes also. 2817 if (array_klasses() != nullptr) { 2818 array_klasses()->remove_java_mirror(); 2819 } 2820 } 2821 2822 void InstanceKlass::init_shared_package_entry() { 2823 assert(CDSConfig::is_dumping_archive(), "must be"); 2824 #if !INCLUDE_CDS_JAVA_HEAP 2825 _package_entry = nullptr; 2826 #else 2827 if (CDSConfig::is_dumping_full_module_graph()) { 2828 if (is_shared_unregistered_class()) { 2829 _package_entry = nullptr; 2830 } else { 2831 _package_entry = PackageEntry::get_archived_entry(_package_entry); 2832 } 2833 } else if (CDSConfig::is_dumping_dynamic_archive() && 2834 CDSConfig::is_using_full_module_graph() && 2835 MetaspaceShared::is_in_shared_metaspace(_package_entry)) { 2836 // _package_entry is an archived package in the base archive. Leave it as is. 2837 } else { 2838 _package_entry = nullptr; 2839 } 2840 ArchivePtrMarker::mark_pointer((address**)&_package_entry); 2841 #endif 2842 } 2843 2844 void InstanceKlass::compute_has_loops_flag_for_methods() { 2845 Array<Method*>* methods = this->methods(); 2846 for (int index = 0; index < methods->length(); ++index) { 2847 Method* m = methods->at(index); 2848 if (!m->is_overpass()) { // work around JDK-8305771 2849 m->compute_has_loops_flag(); 2850 } 2851 } 2852 } 2853 2854 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2855 PackageEntry* pkg_entry, TRAPS) { 2856 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded 2857 // before the InstanceKlass is added to the SystemDictionary. Make 2858 // sure the current state is <loaded. 2859 assert(!is_loaded(), "invalid init state"); 2860 assert(!shared_loading_failed(), "Must not try to load failed class again"); 2861 set_package(loader_data, pkg_entry, CHECK); 2862 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2863 2864 if (is_inline_klass()) { 2865 InlineKlass::cast(this)->initialize_calling_convention(CHECK); 2866 } 2867 2868 Array<Method*>* methods = this->methods(); 2869 int num_methods = methods->length(); 2870 for (int index = 0; index < num_methods; ++index) { 2871 methods->at(index)->restore_unshareable_info(CHECK); 2872 } 2873 #if INCLUDE_JVMTI 2874 if (JvmtiExport::has_redefined_a_class()) { 2875 // Reinitialize vtable because RedefineClasses may have changed some 2876 // entries in this vtable for super classes so the CDS vtable might 2877 // point to old or obsolete entries. RedefineClasses doesn't fix up 2878 // vtables in the shared system dictionary, only the main one. 2879 // It also redefines the itable too so fix that too. 2880 // First fix any default methods that point to a super class that may 2881 // have been redefined. 2882 bool trace_name_printed = false; 2883 adjust_default_methods(&trace_name_printed); 2884 vtable().initialize_vtable(); 2885 itable().initialize_itable(); 2886 } 2887 #endif 2888 2889 // restore constant pool resolved references 2890 constants()->restore_unshareable_info(CHECK); 2891 2892 if (array_klasses() != nullptr) { 2893 // To get a consistent list of classes we need MultiArray_lock to ensure 2894 // array classes aren't observed while they are being restored. 2895 RecursiveLocker rl(MultiArray_lock, THREAD); 2896 assert(this == ObjArrayKlass::cast(array_klasses())->bottom_klass(), "sanity"); 2897 // Array classes have null protection domain. 2898 // --> see ArrayKlass::complete_create_array_klass() 2899 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK); 2900 } 2901 2902 // Initialize @ValueBased class annotation if not already set in the archived klass. 2903 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) { 2904 set_is_value_based(); 2905 } 2906 } 2907 2908 // Check if a class or any of its supertypes has a version older than 50. 2909 // CDS will not perform verification of old classes during dump time because 2910 // without changing the old verifier, the verification constraint cannot be 2911 // retrieved during dump time. 2912 // Verification of archived old classes will be performed during run time. 2913 bool InstanceKlass::can_be_verified_at_dumptime() const { 2914 if (MetaspaceShared::is_in_shared_metaspace(this)) { 2915 // This is a class that was dumped into the base archive, so we know 2916 // it was verified at dump time. 2917 return true; 2918 } 2919 if (major_version() < 50 /*JAVA_6_VERSION*/) { 2920 return false; 2921 } 2922 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) { 2923 return false; 2924 } 2925 Array<InstanceKlass*>* interfaces = local_interfaces(); 2926 int len = interfaces->length(); 2927 for (int i = 0; i < len; i++) { 2928 if (!interfaces->at(i)->can_be_verified_at_dumptime()) { 2929 return false; 2930 } 2931 } 2932 return true; 2933 } 2934 2935 bool InstanceKlass::methods_contain_jsr_bytecode() const { 2936 Thread* thread = Thread::current(); 2937 for (int i = 0; i < _methods->length(); i++) { 2938 methodHandle m(thread, _methods->at(i)); 2939 BytecodeStream bcs(m); 2940 while (!bcs.is_last_bytecode()) { 2941 Bytecodes::Code opcode = bcs.next(); 2942 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) { 2943 return true; 2944 } 2945 } 2946 } 2947 return false; 2948 } 2949 #endif // INCLUDE_CDS 2950 2951 #if INCLUDE_JVMTI 2952 static void clear_all_breakpoints(Method* m) { 2953 m->clear_all_breakpoints(); 2954 } 2955 #endif 2956 2957 void InstanceKlass::unload_class(InstanceKlass* ik) { 2958 // Release dependencies. 2959 ik->dependencies().remove_all_dependents(); 2960 2961 // notify the debugger 2962 if (JvmtiExport::should_post_class_unload()) { 2963 JvmtiExport::post_class_unload(ik); 2964 } 2965 2966 // notify ClassLoadingService of class unload 2967 ClassLoadingService::notify_class_unloaded(ik); 2968 2969 SystemDictionaryShared::handle_class_unloading(ik); 2970 2971 if (log_is_enabled(Info, class, unload)) { 2972 ResourceMark rm; 2973 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik)); 2974 } 2975 2976 Events::log_class_unloading(Thread::current(), ik); 2977 2978 #if INCLUDE_JFR 2979 assert(ik != nullptr, "invariant"); 2980 EventClassUnload event; 2981 event.set_unloadedClass(ik); 2982 event.set_definingClassLoader(ik->class_loader_data()); 2983 event.commit(); 2984 #endif 2985 } 2986 2987 static void method_release_C_heap_structures(Method* m) { 2988 m->release_C_heap_structures(); 2989 } 2990 2991 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata. 2992 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) { 2993 // Clean up C heap 2994 Klass::release_C_heap_structures(); 2995 2996 // Deallocate and call destructors for MDO mutexes 2997 if (release_sub_metadata) { 2998 methods_do(method_release_C_heap_structures); 2999 } 3000 3001 // Deallocate oop map cache 3002 if (_oop_map_cache != nullptr) { 3003 delete _oop_map_cache; 3004 _oop_map_cache = nullptr; 3005 } 3006 3007 // Deallocate JNI identifiers for jfieldIDs 3008 JNIid::deallocate(jni_ids()); 3009 set_jni_ids(nullptr); 3010 3011 jmethodID* jmeths = methods_jmethod_ids_acquire(); 3012 if (jmeths != nullptr) { 3013 release_set_methods_jmethod_ids(nullptr); 3014 FreeHeap(jmeths); 3015 } 3016 3017 assert(_dep_context == nullptr, 3018 "dependencies should already be cleaned"); 3019 3020 #if INCLUDE_JVMTI 3021 // Deallocate breakpoint records 3022 if (breakpoints() != nullptr) { 3023 methods_do(clear_all_breakpoints); 3024 assert(breakpoints() == nullptr, "should have cleared breakpoints"); 3025 } 3026 3027 // deallocate the cached class file 3028 if (_cached_class_file != nullptr) { 3029 os::free(_cached_class_file); 3030 _cached_class_file = nullptr; 3031 } 3032 #endif 3033 3034 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 3035 3036 if (release_sub_metadata) { 3037 constants()->release_C_heap_structures(); 3038 } 3039 } 3040 3041 // The constant pool is on stack if any of the methods are executing or 3042 // referenced by handles. 3043 bool InstanceKlass::on_stack() const { 3044 return _constants->on_stack(); 3045 } 3046 3047 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); } 3048 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); } 3049 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); } 3050 3051 // minor and major version numbers of class file 3052 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); } 3053 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); } 3054 u2 InstanceKlass::major_version() const { return _constants->major_version(); } 3055 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); } 3056 3057 InstanceKlass* InstanceKlass::get_klass_version(int version) { 3058 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) { 3059 if (ik->constants()->version() == version) { 3060 return ik; 3061 } 3062 } 3063 return nullptr; 3064 } 3065 3066 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 3067 if (array == nullptr) { 3068 _source_debug_extension = nullptr; 3069 } else { 3070 // Adding one to the attribute length in order to store a null terminator 3071 // character could cause an overflow because the attribute length is 3072 // already coded with an u4 in the classfile, but in practice, it's 3073 // unlikely to happen. 3074 assert((length+1) > length, "Overflow checking"); 3075 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 3076 for (int i = 0; i < length; i++) { 3077 sde[i] = array[i]; 3078 } 3079 sde[length] = '\0'; 3080 _source_debug_extension = sde; 3081 } 3082 } 3083 3084 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); } 3085 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); } 3086 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); } 3087 3088 const char* InstanceKlass::signature_name() const { 3089 return signature_name_of_carrier(JVM_SIGNATURE_CLASS); 3090 } 3091 3092 const char* InstanceKlass::signature_name_of_carrier(char c) const { 3093 // Get the internal name as a c string 3094 const char* src = (const char*) (name()->as_C_string()); 3095 const int src_length = (int)strlen(src); 3096 3097 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 3098 3099 // Add L or Q as type indicator 3100 int dest_index = 0; 3101 dest[dest_index++] = c; 3102 3103 // Add the actual class name 3104 for (int src_index = 0; src_index < src_length; ) { 3105 dest[dest_index++] = src[src_index++]; 3106 } 3107 3108 if (is_hidden()) { // Replace the last '+' with a '.'. 3109 for (int index = (int)src_length; index > 0; index--) { 3110 if (dest[index] == '+') { 3111 dest[index] = JVM_SIGNATURE_DOT; 3112 break; 3113 } 3114 } 3115 } 3116 3117 // Add the semicolon and the null 3118 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 3119 dest[dest_index] = '\0'; 3120 return dest; 3121 } 3122 3123 ModuleEntry* InstanceKlass::module() const { 3124 if (is_hidden() && 3125 in_unnamed_package() && 3126 class_loader_data()->has_class_mirror_holder()) { 3127 // For a non-strong hidden class defined to an unnamed package, 3128 // its (class held) CLD will not have an unnamed module created for it. 3129 // Two choices to find the correct ModuleEntry: 3130 // 1. If hidden class is within a nest, use nest host's module 3131 // 2. Find the unnamed module off from the class loader 3132 // For now option #2 is used since a nest host is not set until 3133 // after the instance class is created in jvm_lookup_define_class(). 3134 if (class_loader_data()->is_boot_class_loader_data()) { 3135 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 3136 } else { 3137 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 3138 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 3139 return java_lang_Module::module_entry(module); 3140 } 3141 } 3142 3143 // Class is in a named package 3144 if (!in_unnamed_package()) { 3145 return _package_entry->module(); 3146 } 3147 3148 // Class is in an unnamed package, return its loader's unnamed module 3149 return class_loader_data()->unnamed_module(); 3150 } 3151 3152 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 3153 3154 // ensure java/ packages only loaded by boot or platform builtin loaders 3155 // not needed for shared class since CDS does not archive prohibited classes. 3156 if (!is_shared()) { 3157 check_prohibited_package(name(), loader_data, CHECK); 3158 } 3159 3160 if (is_shared() && _package_entry != nullptr) { 3161 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) { 3162 // we can use the saved package 3163 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be"); 3164 return; 3165 } else { 3166 _package_entry = nullptr; 3167 } 3168 } 3169 3170 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol 3171 // it returns, so we need to decrement it when the current function exits. 3172 TempNewSymbol from_class_name = 3173 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name()); 3174 3175 Symbol* pkg_name; 3176 if (pkg_entry != nullptr) { 3177 pkg_name = pkg_entry->name(); 3178 } else { 3179 pkg_name = from_class_name; 3180 } 3181 3182 if (pkg_name != nullptr && loader_data != nullptr) { 3183 3184 // Find in class loader's package entry table. 3185 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 3186 3187 // If the package name is not found in the loader's package 3188 // entry table, it is an indication that the package has not 3189 // been defined. Consider it defined within the unnamed module. 3190 if (_package_entry == nullptr) { 3191 3192 if (!ModuleEntryTable::javabase_defined()) { 3193 // Before java.base is defined during bootstrapping, define all packages in 3194 // the java.base module. If a non-java.base package is erroneously placed 3195 // in the java.base module it will be caught later when java.base 3196 // is defined by ModuleEntryTable::verify_javabase_packages check. 3197 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null"); 3198 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 3199 } else { 3200 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null"); 3201 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module()); 3202 } 3203 3204 // A package should have been successfully created 3205 DEBUG_ONLY(ResourceMark rm(THREAD)); 3206 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s", 3207 name()->as_C_string(), loader_data->loader_name_and_id()); 3208 } 3209 3210 if (log_is_enabled(Debug, module)) { 3211 ResourceMark rm(THREAD); 3212 ModuleEntry* m = _package_entry->module(); 3213 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 3214 external_name(), 3215 pkg_name->as_C_string(), 3216 loader_data->loader_name_and_id(), 3217 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 3218 } 3219 } else { 3220 ResourceMark rm(THREAD); 3221 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 3222 external_name(), 3223 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null", 3224 UNNAMED_MODULE); 3225 } 3226 } 3227 3228 // Function set_classpath_index ensures that for a non-null _package_entry 3229 // of the InstanceKlass, the entry is in the boot loader's package entry table. 3230 // It then sets the classpath_index in the package entry record. 3231 // 3232 // The classpath_index field is used to find the entry on the boot loader class 3233 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 3234 // in an unnamed module. It is also used to indicate (for all packages whose 3235 // classes are loaded by the boot loader) that at least one of the package's 3236 // classes has been loaded. 3237 void InstanceKlass::set_classpath_index(s2 path_index) { 3238 if (_package_entry != nullptr) { 3239 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 3240 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 3241 assert(path_index != -1, "Unexpected classpath_index"); 3242 _package_entry->set_classpath_index(path_index); 3243 } 3244 } 3245 3246 // different versions of is_same_class_package 3247 3248 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 3249 oop classloader1 = this->class_loader(); 3250 PackageEntry* classpkg1 = this->package(); 3251 if (class2->is_objArray_klass()) { 3252 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 3253 } 3254 3255 oop classloader2; 3256 PackageEntry* classpkg2; 3257 if (class2->is_instance_klass()) { 3258 classloader2 = class2->class_loader(); 3259 classpkg2 = class2->package(); 3260 } else { 3261 assert(class2->is_typeArray_klass(), "should be type array"); 3262 classloader2 = nullptr; 3263 classpkg2 = nullptr; 3264 } 3265 3266 // Same package is determined by comparing class loader 3267 // and package entries. Both must be the same. This rule 3268 // applies even to classes that are defined in the unnamed 3269 // package, they still must have the same class loader. 3270 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 3271 return true; 3272 } 3273 3274 return false; 3275 } 3276 3277 // return true if this class and other_class are in the same package. Classloader 3278 // and classname information is enough to determine a class's package 3279 bool InstanceKlass::is_same_class_package(oop other_class_loader, 3280 const Symbol* other_class_name) const { 3281 if (class_loader() != other_class_loader) { 3282 return false; 3283 } 3284 if (name()->fast_compare(other_class_name) == 0) { 3285 return true; 3286 } 3287 3288 { 3289 ResourceMark rm; 3290 3291 bool bad_class_name = false; 3292 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 3293 if (bad_class_name) { 3294 return false; 3295 } 3296 // Check that package_from_class_name() returns null, not "", if there is no package. 3297 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string"); 3298 3299 const Symbol* const this_package_name = 3300 this->package() != nullptr ? this->package()->name() : nullptr; 3301 3302 if (this_package_name == nullptr || other_pkg == nullptr) { 3303 // One of the two doesn't have a package. Only return true if the other 3304 // one also doesn't have a package. 3305 return this_package_name == other_pkg; 3306 } 3307 3308 // Check if package is identical 3309 return this_package_name->fast_compare(other_pkg) == 0; 3310 } 3311 } 3312 3313 static bool is_prohibited_package_slow(Symbol* class_name) { 3314 // Caller has ResourceMark 3315 int length; 3316 jchar* unicode = class_name->as_unicode(length); 3317 return (length >= 5 && 3318 unicode[0] == 'j' && 3319 unicode[1] == 'a' && 3320 unicode[2] == 'v' && 3321 unicode[3] == 'a' && 3322 unicode[4] == '/'); 3323 } 3324 3325 // Only boot and platform class loaders can define classes in "java/" packages. 3326 void InstanceKlass::check_prohibited_package(Symbol* class_name, 3327 ClassLoaderData* loader_data, 3328 TRAPS) { 3329 if (!loader_data->is_boot_class_loader_data() && 3330 !loader_data->is_platform_class_loader_data() && 3331 class_name != nullptr && class_name->utf8_length() >= 5) { 3332 ResourceMark rm(THREAD); 3333 bool prohibited; 3334 const u1* base = class_name->base(); 3335 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) { 3336 prohibited = is_prohibited_package_slow(class_name); 3337 } else { 3338 char* name = class_name->as_C_string(); 3339 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/'); 3340 } 3341 if (prohibited) { 3342 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 3343 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'"); 3344 char* name = pkg_name->as_C_string(); 3345 const char* class_loader_name = loader_data->loader_name_and_id(); 3346 StringUtils::replace_no_expand(name, "/", "."); 3347 const char* msg_text1 = "Class loader (instance of): "; 3348 const char* msg_text2 = " tried to load prohibited package name: "; 3349 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 3350 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 3351 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 3352 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 3353 } 3354 } 3355 return; 3356 } 3357 3358 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 3359 constantPoolHandle i_cp(THREAD, constants()); 3360 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 3361 int ioff = iter.inner_class_info_index(); 3362 if (ioff != 0) { 3363 // Check to see if the name matches the class we're looking for 3364 // before attempting to find the class. 3365 if (i_cp->klass_name_at_matches(this, ioff)) { 3366 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 3367 if (this == inner_klass) { 3368 *ooff = iter.outer_class_info_index(); 3369 *noff = iter.inner_name_index(); 3370 return true; 3371 } 3372 } 3373 } 3374 } 3375 return false; 3376 } 3377 3378 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 3379 InstanceKlass* outer_klass = nullptr; 3380 *inner_is_member = false; 3381 int ooff = 0, noff = 0; 3382 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 3383 if (has_inner_classes_attr) { 3384 constantPoolHandle i_cp(THREAD, constants()); 3385 if (ooff != 0) { 3386 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 3387 if (!ok->is_instance_klass()) { 3388 // If the outer class is not an instance klass then it cannot have 3389 // declared any inner classes. 3390 ResourceMark rm(THREAD); 3391 Exceptions::fthrow( 3392 THREAD_AND_LOCATION, 3393 vmSymbols::java_lang_IncompatibleClassChangeError(), 3394 "%s and %s disagree on InnerClasses attribute", 3395 ok->external_name(), 3396 external_name()); 3397 return nullptr; 3398 } 3399 outer_klass = InstanceKlass::cast(ok); 3400 *inner_is_member = true; 3401 } 3402 if (nullptr == outer_klass) { 3403 // It may be a local class; try for that. 3404 int encl_method_class_idx = enclosing_method_class_index(); 3405 if (encl_method_class_idx != 0) { 3406 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 3407 outer_klass = InstanceKlass::cast(ok); 3408 *inner_is_member = false; 3409 } 3410 } 3411 } 3412 3413 // If no inner class attribute found for this class. 3414 if (nullptr == outer_klass) return nullptr; 3415 3416 // Throws an exception if outer klass has not declared k as an inner klass 3417 // We need evidence that each klass knows about the other, or else 3418 // the system could allow a spoof of an inner class to gain access rights. 3419 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 3420 return outer_klass; 3421 } 3422 3423 jint InstanceKlass::compute_modifier_flags() const { 3424 jint access = access_flags().as_int(); 3425 3426 // But check if it happens to be member class. 3427 InnerClassesIterator iter(this); 3428 for (; !iter.done(); iter.next()) { 3429 int ioff = iter.inner_class_info_index(); 3430 // Inner class attribute can be zero, skip it. 3431 // Strange but true: JVM spec. allows null inner class refs. 3432 if (ioff == 0) continue; 3433 3434 // only look at classes that are already loaded 3435 // since we are looking for the flags for our self. 3436 Symbol* inner_name = constants()->klass_name_at(ioff); 3437 if (name() == inner_name) { 3438 // This is really a member class. 3439 access = iter.inner_access_flags(); 3440 break; 3441 } 3442 } 3443 return (access & JVM_ACC_WRITTEN_FLAGS); 3444 } 3445 3446 jint InstanceKlass::jvmti_class_status() const { 3447 jint result = 0; 3448 3449 if (is_linked()) { 3450 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3451 } 3452 3453 if (is_initialized()) { 3454 assert(is_linked(), "Class status is not consistent"); 3455 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3456 } 3457 if (is_in_error_state()) { 3458 result |= JVMTI_CLASS_STATUS_ERROR; 3459 } 3460 return result; 3461 } 3462 3463 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) { 3464 bool implements_interface; // initialized by method_at_itable_or_null 3465 Method* m = method_at_itable_or_null(holder, index, 3466 implements_interface); // out parameter 3467 if (m != nullptr) { 3468 assert(implements_interface, "sanity"); 3469 return m; 3470 } else if (implements_interface) { 3471 // Throw AbstractMethodError since corresponding itable slot is empty. 3472 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3473 } else { 3474 // If the interface isn't implemented by the receiver class, 3475 // the VM should throw IncompatibleClassChangeError. 3476 ResourceMark rm(THREAD); 3477 stringStream ss; 3478 bool same_module = (module() == holder->module()); 3479 ss.print("Receiver class %s does not implement " 3480 "the interface %s defining the method to be called " 3481 "(%s%s%s)", 3482 external_name(), holder->external_name(), 3483 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3484 (same_module) ? "" : "; ", 3485 (same_module) ? "" : holder->class_in_module_of_loader()); 3486 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3487 } 3488 } 3489 3490 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) { 3491 klassItable itable(this); 3492 for (int i = 0; i < itable.size_offset_table(); i++) { 3493 itableOffsetEntry* offset_entry = itable.offset_entry(i); 3494 if (offset_entry->interface_klass() == holder) { 3495 implements_interface = true; 3496 itableMethodEntry* ime = offset_entry->first_method_entry(this); 3497 Method* m = ime[index].method(); 3498 return m; 3499 } 3500 } 3501 implements_interface = false; 3502 return nullptr; // offset entry not found 3503 } 3504 3505 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) { 3506 assert(is_linked(), "required"); 3507 assert(intf_method->method_holder()->is_interface(), "not an interface method"); 3508 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented"); 3509 3510 int vtable_index = Method::invalid_vtable_index; 3511 Symbol* name = intf_method->name(); 3512 Symbol* signature = intf_method->signature(); 3513 3514 // First check in default method array 3515 if (!intf_method->is_abstract() && default_methods() != nullptr) { 3516 int index = find_method_index(default_methods(), 3517 name, signature, 3518 Klass::OverpassLookupMode::find, 3519 Klass::StaticLookupMode::find, 3520 Klass::PrivateLookupMode::find); 3521 if (index >= 0) { 3522 vtable_index = default_vtable_indices()->at(index); 3523 } 3524 } 3525 if (vtable_index == Method::invalid_vtable_index) { 3526 // get vtable_index for miranda methods 3527 klassVtable vt = vtable(); 3528 vtable_index = vt.index_of_miranda(name, signature); 3529 } 3530 return vtable_index; 3531 } 3532 3533 #if INCLUDE_JVMTI 3534 // update default_methods for redefineclasses for methods that are 3535 // not yet in the vtable due to concurrent subclass define and superinterface 3536 // redefinition 3537 // Note: those in the vtable, should have been updated via adjust_method_entries 3538 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3539 // search the default_methods for uses of either obsolete or EMCP methods 3540 if (default_methods() != nullptr) { 3541 for (int index = 0; index < default_methods()->length(); index ++) { 3542 Method* old_method = default_methods()->at(index); 3543 if (old_method == nullptr || !old_method->is_old()) { 3544 continue; // skip uninteresting entries 3545 } 3546 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3547 Method* new_method = old_method->get_new_method(); 3548 default_methods()->at_put(index, new_method); 3549 3550 if (log_is_enabled(Info, redefine, class, update)) { 3551 ResourceMark rm; 3552 if (!(*trace_name_printed)) { 3553 log_info(redefine, class, update) 3554 ("adjust: klassname=%s default methods from name=%s", 3555 external_name(), old_method->method_holder()->external_name()); 3556 *trace_name_printed = true; 3557 } 3558 log_debug(redefine, class, update, vtables) 3559 ("default method update: %s(%s) ", 3560 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3561 } 3562 } 3563 } 3564 } 3565 #endif // INCLUDE_JVMTI 3566 3567 // On-stack replacement stuff 3568 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3569 assert_lock_strong(NMethodState_lock); 3570 #ifndef PRODUCT 3571 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3572 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3573 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3574 #endif 3575 // only one compilation can be active 3576 assert(n->is_osr_method(), "wrong kind of nmethod"); 3577 n->set_osr_link(osr_nmethods_head()); 3578 set_osr_nmethods_head(n); 3579 // Raise the highest osr level if necessary 3580 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level())); 3581 3582 // Get rid of the osr methods for the same bci that have lower levels. 3583 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3584 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3585 if (inv != nullptr && inv->is_in_use()) { 3586 inv->make_not_entrant(); 3587 } 3588 } 3589 } 3590 3591 // Remove osr nmethod from the list. Return true if found and removed. 3592 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3593 // This is a short non-blocking critical region, so the no safepoint check is ok. 3594 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3595 assert(n->is_osr_method(), "wrong kind of nmethod"); 3596 nmethod* last = nullptr; 3597 nmethod* cur = osr_nmethods_head(); 3598 int max_level = CompLevel_none; // Find the max comp level excluding n 3599 Method* m = n->method(); 3600 // Search for match 3601 bool found = false; 3602 while(cur != nullptr && cur != n) { 3603 if (m == cur->method()) { 3604 // Find max level before n 3605 max_level = MAX2(max_level, cur->comp_level()); 3606 } 3607 last = cur; 3608 cur = cur->osr_link(); 3609 } 3610 nmethod* next = nullptr; 3611 if (cur == n) { 3612 found = true; 3613 next = cur->osr_link(); 3614 if (last == nullptr) { 3615 // Remove first element 3616 set_osr_nmethods_head(next); 3617 } else { 3618 last->set_osr_link(next); 3619 } 3620 } 3621 n->set_osr_link(nullptr); 3622 cur = next; 3623 while (cur != nullptr) { 3624 // Find max level after n 3625 if (m == cur->method()) { 3626 max_level = MAX2(max_level, cur->comp_level()); 3627 } 3628 cur = cur->osr_link(); 3629 } 3630 m->set_highest_osr_comp_level(max_level); 3631 return found; 3632 } 3633 3634 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) { 3635 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3636 nmethod* osr = osr_nmethods_head(); 3637 int found = 0; 3638 while (osr != nullptr) { 3639 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3640 if (osr->method() == m) { 3641 deopt_scope->mark(osr); 3642 found++; 3643 } 3644 osr = osr->osr_link(); 3645 } 3646 return found; 3647 } 3648 3649 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3650 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3651 nmethod* osr = osr_nmethods_head(); 3652 nmethod* best = nullptr; 3653 while (osr != nullptr) { 3654 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3655 // There can be a time when a c1 osr method exists but we are waiting 3656 // for a c2 version. When c2 completes its osr nmethod we will trash 3657 // the c1 version and only be able to find the c2 version. However 3658 // while we overflow in the c1 code at back branches we don't want to 3659 // try and switch to the same code as we are already running 3660 3661 if (osr->method() == m && 3662 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3663 if (match_level) { 3664 if (osr->comp_level() == comp_level) { 3665 // Found a match - return it. 3666 return osr; 3667 } 3668 } else { 3669 if (best == nullptr || (osr->comp_level() > best->comp_level())) { 3670 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) { 3671 // Found the best possible - return it. 3672 return osr; 3673 } 3674 best = osr; 3675 } 3676 } 3677 } 3678 osr = osr->osr_link(); 3679 } 3680 3681 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set"); 3682 if (best != nullptr && best->comp_level() >= comp_level) { 3683 return best; 3684 } 3685 return nullptr; 3686 } 3687 3688 // ----------------------------------------------------------------------------------------------------- 3689 // Printing 3690 3691 #define BULLET " - " 3692 3693 static const char* state_names[] = { 3694 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3695 }; 3696 3697 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) { 3698 ResourceMark rm; 3699 int* forward_refs = NEW_RESOURCE_ARRAY(int, len); 3700 for (int i = 0; i < len; i++) forward_refs[i] = 0; 3701 for (int i = 0; i < len; i++) { 3702 intptr_t e = start[i]; 3703 st->print("%d : " INTPTR_FORMAT, i, e); 3704 if (forward_refs[i] != 0) { 3705 int from = forward_refs[i]; 3706 int off = (int) start[from]; 3707 st->print(" (offset %d <= [%d])", off, from); 3708 } 3709 if (MetaspaceObj::is_valid((Metadata*)e)) { 3710 st->print(" "); 3711 ((Metadata*)e)->print_value_on(st); 3712 } else if (self != nullptr && e > 0 && e < 0x10000) { 3713 address location = self + e; 3714 int index = (int)((intptr_t*)location - start); 3715 st->print(" (offset %d => [%d])", (int)e, index); 3716 if (index >= 0 && index < len) 3717 forward_refs[index] = i; 3718 } 3719 st->cr(); 3720 } 3721 } 3722 3723 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3724 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st); 3725 } 3726 3727 template<typename T> 3728 static void print_array_on(outputStream* st, Array<T>* array) { 3729 if (array == nullptr) { st->print_cr("nullptr"); return; } 3730 array->print_value_on(st); st->cr(); 3731 if (Verbose || WizardMode) { 3732 for (int i = 0; i < array->length(); i++) { 3733 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr(); 3734 } 3735 } 3736 } 3737 3738 static void print_array_on(outputStream* st, Array<int>* array) { 3739 if (array == nullptr) { st->print_cr("nullptr"); return; } 3740 array->print_value_on(st); st->cr(); 3741 if (Verbose || WizardMode) { 3742 for (int i = 0; i < array->length(); i++) { 3743 st->print("%d : %d", i, array->at(i)); st->cr(); 3744 } 3745 } 3746 } 3747 3748 const char* InstanceKlass::init_state_name() const { 3749 return state_names[init_state()]; 3750 } 3751 3752 void InstanceKlass::print_on(outputStream* st) const { 3753 assert(is_klass(), "must be klass"); 3754 Klass::print_on(st); 3755 3756 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3757 st->print(BULLET"klass size: %d", size()); st->cr(); 3758 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3759 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr(); 3760 st->print(BULLET"state: "); st->print_cr("%s", init_state_name()); 3761 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3762 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3763 st->print(BULLET"sub: "); 3764 Klass* sub = subklass(); 3765 int n; 3766 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) { 3767 if (n < MaxSubklassPrintSize) { 3768 sub->print_value_on(st); 3769 st->print(" "); 3770 } 3771 } 3772 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3773 st->cr(); 3774 3775 if (is_interface()) { 3776 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3777 if (nof_implementors() == 1) { 3778 st->print_cr(BULLET"implementor: "); 3779 st->print(" "); 3780 implementor()->print_value_on(st); 3781 st->cr(); 3782 } 3783 } 3784 3785 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3786 st->print(BULLET"methods: "); print_array_on(st, methods()); 3787 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering()); 3788 if (default_methods() != nullptr) { 3789 st->print(BULLET"default_methods: "); print_array_on(st, default_methods()); 3790 } 3791 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices()); 3792 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3793 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3794 3795 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr(); 3796 if (UseSecondarySupersTable) { 3797 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr(); 3798 st->print(BULLET"bitmap: " UINTX_FORMAT_X_0, _bitmap); st->cr(); 3799 } 3800 if (secondary_supers() != nullptr) { 3801 if (Verbose) { 3802 bool is_hashed = UseSecondarySupersTable && (_bitmap != SECONDARY_SUPERS_BITMAP_FULL); 3803 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length()); 3804 for (int i = 0; i < _secondary_supers->length(); i++) { 3805 ResourceMark rm; // for external_name() 3806 Klass* secondary_super = _secondary_supers->at(i); 3807 st->print(BULLET"%2d:", i); 3808 if (is_hashed) { 3809 int home_slot = compute_home_slot(secondary_super, _bitmap); 3810 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK; 3811 st->print(" dist:%02d:", distance); 3812 } 3813 st->print_cr(" %p %s", secondary_super, secondary_super->external_name()); 3814 } 3815 } 3816 } 3817 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3818 3819 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data()); 3820 print_on_maybe_null(st, BULLET"source file: ", source_file_name()); 3821 if (source_debug_extension() != nullptr) { 3822 st->print(BULLET"source debug extension: "); 3823 st->print("%s", source_debug_extension()); 3824 st->cr(); 3825 } 3826 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations()); 3827 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations()); 3828 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations()); 3829 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations()); 3830 { 3831 bool have_pv = false; 3832 // previous versions are linked together through the InstanceKlass 3833 for (InstanceKlass* pv_node = previous_versions(); 3834 pv_node != nullptr; 3835 pv_node = pv_node->previous_versions()) { 3836 if (!have_pv) 3837 st->print(BULLET"previous version: "); 3838 have_pv = true; 3839 pv_node->constants()->print_value_on(st); 3840 } 3841 if (have_pv) st->cr(); 3842 } 3843 3844 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature()); 3845 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3846 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3847 print_on_maybe_null(st, BULLET"record components: ", record_components()); 3848 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr(); 3849 st->print(BULLET"loadable descriptors: "); loadable_descriptors()->print_value_on(st); st->cr(); 3850 if (java_mirror() != nullptr) { 3851 st->print(BULLET"java mirror: "); 3852 java_mirror()->print_value_on(st); 3853 st->cr(); 3854 } else { 3855 st->print_cr(BULLET"java mirror: null"); 3856 } 3857 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3858 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3859 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3860 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st); 3861 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3862 3863 FieldPrinter print_static_field(st); 3864 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3865 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3866 FieldPrinter print_nonstatic_field(st); 3867 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3868 ik->print_nonstatic_fields(&print_nonstatic_field); 3869 3870 st->print(BULLET"non-static oop maps: "); 3871 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3872 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3873 while (map < end_map) { 3874 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3875 map++; 3876 } 3877 st->cr(); 3878 } 3879 3880 void InstanceKlass::print_value_on(outputStream* st) const { 3881 assert(is_klass(), "must be klass"); 3882 if (Verbose || WizardMode) access_flags().print_on(st); 3883 name()->print_value_on(st); 3884 } 3885 3886 void FieldPrinter::do_field(fieldDescriptor* fd) { 3887 _st->print(BULLET); 3888 if (_obj == nullptr) { 3889 fd->print_on(_st); 3890 _st->cr(); 3891 } else { 3892 fd->print_on_for(_st, _obj); 3893 _st->cr(); 3894 } 3895 } 3896 3897 3898 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3899 Klass::oop_print_on(obj, st); 3900 3901 if (this == vmClasses::String_klass()) { 3902 typeArrayOop value = java_lang_String::value(obj); 3903 juint length = java_lang_String::length(obj); 3904 if (value != nullptr && 3905 value->is_typeArray() && 3906 length <= (juint) value->length()) { 3907 st->print(BULLET"string: "); 3908 java_lang_String::print(obj, st); 3909 st->cr(); 3910 } 3911 } 3912 3913 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj)); 3914 FieldPrinter print_field(st, obj); 3915 print_nonstatic_fields(&print_field); 3916 3917 if (this == vmClasses::Class_klass()) { 3918 st->print(BULLET"signature: "); 3919 java_lang_Class::print_signature(obj, st); 3920 st->cr(); 3921 Klass* real_klass = java_lang_Class::as_Klass(obj); 3922 if (real_klass != nullptr && real_klass->is_instance_klass()) { 3923 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj)); 3924 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3925 } 3926 } else if (this == vmClasses::MethodType_klass()) { 3927 st->print(BULLET"signature: "); 3928 java_lang_invoke_MethodType::print_signature(obj, st); 3929 st->cr(); 3930 } 3931 } 3932 3933 #ifndef PRODUCT 3934 3935 bool InstanceKlass::verify_itable_index(int i) { 3936 int method_count = klassItable::method_count_for_interface(this); 3937 assert(i >= 0 && i < method_count, "index out of bounds"); 3938 return true; 3939 } 3940 3941 #endif //PRODUCT 3942 3943 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3944 st->print("a "); 3945 name()->print_value_on(st); 3946 obj->print_address_on(st); 3947 if (this == vmClasses::String_klass() 3948 && java_lang_String::value(obj) != nullptr) { 3949 ResourceMark rm; 3950 int len = java_lang_String::length(obj); 3951 int plen = (len < 24 ? len : 12); 3952 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3953 st->print(" = \"%s\"", str); 3954 if (len > plen) 3955 st->print("...[%d]", len); 3956 } else if (this == vmClasses::Class_klass()) { 3957 Klass* k = java_lang_Class::as_Klass(obj); 3958 st->print(" = "); 3959 if (k != nullptr) { 3960 k->print_value_on(st); 3961 } else { 3962 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3963 st->print("%s", tname ? tname : "type?"); 3964 } 3965 } else if (this == vmClasses::MethodType_klass()) { 3966 st->print(" = "); 3967 java_lang_invoke_MethodType::print_signature(obj, st); 3968 } else if (java_lang_boxing_object::is_instance(obj)) { 3969 st->print(" = "); 3970 java_lang_boxing_object::print(obj, st); 3971 } else if (this == vmClasses::LambdaForm_klass()) { 3972 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3973 if (vmentry != nullptr) { 3974 st->print(" => "); 3975 vmentry->print_value_on(st); 3976 } 3977 } else if (this == vmClasses::MemberName_klass()) { 3978 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3979 if (vmtarget != nullptr) { 3980 st->print(" = "); 3981 vmtarget->print_value_on(st); 3982 } else { 3983 oop clazz = java_lang_invoke_MemberName::clazz(obj); 3984 oop name = java_lang_invoke_MemberName::name(obj); 3985 if (clazz != nullptr) { 3986 clazz->print_value_on(st); 3987 } else { 3988 st->print("null"); 3989 } 3990 st->print("."); 3991 if (name != nullptr) { 3992 name->print_value_on(st); 3993 } else { 3994 st->print("null"); 3995 } 3996 } 3997 } 3998 } 3999 4000 const char* InstanceKlass::internal_name() const { 4001 return external_name(); 4002 } 4003 4004 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 4005 const ModuleEntry* module_entry, 4006 const ClassFileStream* cfs) const { 4007 4008 if (ClassListWriter::is_enabled()) { 4009 ClassListWriter::write(this, cfs); 4010 } 4011 4012 print_class_load_helper(loader_data, module_entry, cfs); 4013 print_class_load_cause_logging(); 4014 } 4015 4016 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data, 4017 const ModuleEntry* module_entry, 4018 const ClassFileStream* cfs) const { 4019 4020 if (!log_is_enabled(Info, class, load)) { 4021 return; 4022 } 4023 4024 ResourceMark rm; 4025 LogMessage(class, load) msg; 4026 stringStream info_stream; 4027 4028 // Name and class hierarchy info 4029 info_stream.print("%s", external_name()); 4030 4031 // Source 4032 if (cfs != nullptr) { 4033 if (cfs->source() != nullptr) { 4034 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string(); 4035 if (module_name != nullptr) { 4036 // When the boot loader created the stream, it didn't know the module name 4037 // yet. Let's format it now. 4038 if (cfs->from_boot_loader_modules_image()) { 4039 info_stream.print(" source: jrt:/%s", module_name); 4040 } else { 4041 info_stream.print(" source: %s", cfs->source()); 4042 } 4043 } else { 4044 info_stream.print(" source: %s", cfs->source()); 4045 } 4046 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 4047 Thread* current = Thread::current(); 4048 Klass* caller = current->is_Java_thread() ? 4049 JavaThread::cast(current)->security_get_caller_class(1): 4050 nullptr; 4051 // caller can be null, for example, during a JVMTI VM_Init hook 4052 if (caller != nullptr) { 4053 info_stream.print(" source: instance of %s", caller->external_name()); 4054 } else { 4055 // source is unknown 4056 } 4057 } else { 4058 oop class_loader = loader_data->class_loader(); 4059 info_stream.print(" source: %s", class_loader->klass()->external_name()); 4060 } 4061 } else { 4062 assert(this->is_shared(), "must be"); 4063 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 4064 info_stream.print(" source: shared objects file (top)"); 4065 } else { 4066 info_stream.print(" source: shared objects file"); 4067 } 4068 } 4069 4070 msg.info("%s", info_stream.as_string()); 4071 4072 if (log_is_enabled(Debug, class, load)) { 4073 stringStream debug_stream; 4074 4075 // Class hierarchy info 4076 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT, 4077 p2i(this), p2i(superklass())); 4078 4079 // Interfaces 4080 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) { 4081 debug_stream.print(" interfaces:"); 4082 int length = local_interfaces()->length(); 4083 for (int i = 0; i < length; i++) { 4084 debug_stream.print(" " PTR_FORMAT, 4085 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 4086 } 4087 } 4088 4089 // Class loader 4090 debug_stream.print(" loader: ["); 4091 loader_data->print_value_on(&debug_stream); 4092 debug_stream.print("]"); 4093 4094 // Classfile checksum 4095 if (cfs) { 4096 debug_stream.print(" bytes: %d checksum: %08x", 4097 cfs->length(), 4098 ClassLoader::crc32(0, (const char*)cfs->buffer(), 4099 cfs->length())); 4100 } 4101 4102 msg.debug("%s", debug_stream.as_string()); 4103 } 4104 } 4105 4106 void InstanceKlass::print_class_load_cause_logging() const { 4107 bool log_cause_native = log_is_enabled(Info, class, load, cause, native); 4108 if (log_cause_native || log_is_enabled(Info, class, load, cause)) { 4109 JavaThread* current = JavaThread::current(); 4110 ResourceMark rm(current); 4111 const char* name = external_name(); 4112 4113 if (LogClassLoadingCauseFor == nullptr || 4114 (strcmp("*", LogClassLoadingCauseFor) != 0 && 4115 strstr(name, LogClassLoadingCauseFor) == nullptr)) { 4116 return; 4117 } 4118 4119 // Log Java stack first 4120 { 4121 LogMessage(class, load, cause) msg; 4122 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4123 4124 info_stream.print_cr("Java stack when loading %s:", name); 4125 current->print_stack_on(&info_stream); 4126 } 4127 4128 // Log native stack second 4129 if (log_cause_native) { 4130 // Log to string first so that lines can be indented 4131 stringStream stack_stream; 4132 char buf[O_BUFLEN]; 4133 address lastpc = nullptr; 4134 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) { 4135 // We have printed the native stack in platform-specific code, 4136 // so nothing else to do in this case. 4137 } else { 4138 frame f = os::current_frame(); 4139 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */, 4140 -1 /* max stack_stream */, buf, O_BUFLEN); 4141 } 4142 4143 LogMessage(class, load, cause, native) msg; 4144 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4145 info_stream.print_cr("Native stack when loading %s:", name); 4146 4147 // Print each native stack line to the log 4148 int size = (int) stack_stream.size(); 4149 char* stack = stack_stream.as_string(); 4150 char* stack_end = stack + size; 4151 char* line_start = stack; 4152 for (char* p = stack; p < stack_end; p++) { 4153 if (*p == '\n') { 4154 *p = '\0'; 4155 info_stream.print_cr("\t%s", line_start); 4156 line_start = p + 1; 4157 } 4158 } 4159 if (line_start < stack_end) { 4160 info_stream.print_cr("\t%s", line_start); 4161 } 4162 } 4163 } 4164 } 4165 4166 // Verification 4167 4168 class VerifyFieldClosure: public BasicOopIterateClosure { 4169 protected: 4170 template <class T> void do_oop_work(T* p) { 4171 oop obj = RawAccess<>::oop_load(p); 4172 if (!oopDesc::is_oop_or_null(obj)) { 4173 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 4174 Universe::print_on(tty); 4175 guarantee(false, "boom"); 4176 } 4177 } 4178 public: 4179 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 4180 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 4181 }; 4182 4183 void InstanceKlass::verify_on(outputStream* st) { 4184 #ifndef PRODUCT 4185 // Avoid redundant verifies, this really should be in product. 4186 if (_verify_count == Universe::verify_count()) return; 4187 _verify_count = Universe::verify_count(); 4188 #endif 4189 4190 // Verify Klass 4191 Klass::verify_on(st); 4192 4193 // Verify that klass is present in ClassLoaderData 4194 guarantee(class_loader_data()->contains_klass(this), 4195 "this class isn't found in class loader data"); 4196 4197 // Verify vtables 4198 if (is_linked()) { 4199 // $$$ This used to be done only for m/s collections. Doing it 4200 // always seemed a valid generalization. (DLD -- 6/00) 4201 vtable().verify(st); 4202 } 4203 4204 // Verify first subklass 4205 if (subklass() != nullptr) { 4206 guarantee(subklass()->is_klass(), "should be klass"); 4207 } 4208 4209 // Verify siblings 4210 Klass* super = this->super(); 4211 Klass* sib = next_sibling(); 4212 if (sib != nullptr) { 4213 if (sib == this) { 4214 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 4215 } 4216 4217 guarantee(sib->is_klass(), "should be klass"); 4218 guarantee(sib->super() == super, "siblings should have same superklass"); 4219 } 4220 4221 // Verify local interfaces 4222 if (local_interfaces()) { 4223 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 4224 for (int j = 0; j < local_interfaces->length(); j++) { 4225 InstanceKlass* e = local_interfaces->at(j); 4226 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 4227 } 4228 } 4229 4230 // Verify transitive interfaces 4231 if (transitive_interfaces() != nullptr) { 4232 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 4233 for (int j = 0; j < transitive_interfaces->length(); j++) { 4234 InstanceKlass* e = transitive_interfaces->at(j); 4235 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 4236 } 4237 } 4238 4239 // Verify methods 4240 if (methods() != nullptr) { 4241 Array<Method*>* methods = this->methods(); 4242 for (int j = 0; j < methods->length(); j++) { 4243 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4244 } 4245 for (int j = 0; j < methods->length() - 1; j++) { 4246 Method* m1 = methods->at(j); 4247 Method* m2 = methods->at(j + 1); 4248 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4249 } 4250 } 4251 4252 // Verify method ordering 4253 if (method_ordering() != nullptr) { 4254 Array<int>* method_ordering = this->method_ordering(); 4255 int length = method_ordering->length(); 4256 if (JvmtiExport::can_maintain_original_method_order() || 4257 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) { 4258 guarantee(length == methods()->length(), "invalid method ordering length"); 4259 jlong sum = 0; 4260 for (int j = 0; j < length; j++) { 4261 int original_index = method_ordering->at(j); 4262 guarantee(original_index >= 0, "invalid method ordering index"); 4263 guarantee(original_index < length, "invalid method ordering index"); 4264 sum += original_index; 4265 } 4266 // Verify sum of indices 0,1,...,length-1 4267 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 4268 } else { 4269 guarantee(length == 0, "invalid method ordering length"); 4270 } 4271 } 4272 4273 // Verify default methods 4274 if (default_methods() != nullptr) { 4275 Array<Method*>* methods = this->default_methods(); 4276 for (int j = 0; j < methods->length(); j++) { 4277 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4278 } 4279 for (int j = 0; j < methods->length() - 1; j++) { 4280 Method* m1 = methods->at(j); 4281 Method* m2 = methods->at(j + 1); 4282 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4283 } 4284 } 4285 4286 // Verify JNI static field identifiers 4287 if (jni_ids() != nullptr) { 4288 jni_ids()->verify(this); 4289 } 4290 4291 // Verify other fields 4292 if (constants() != nullptr) { 4293 guarantee(constants()->is_constantPool(), "should be constant pool"); 4294 } 4295 } 4296 4297 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 4298 Klass::oop_verify_on(obj, st); 4299 VerifyFieldClosure blk; 4300 obj->oop_iterate(&blk); 4301 } 4302 4303 4304 // JNIid class for jfieldIDs only 4305 // Note to reviewers: 4306 // These JNI functions are just moved over to column 1 and not changed 4307 // in the compressed oops workspace. 4308 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 4309 _holder = holder; 4310 _offset = offset; 4311 _next = next; 4312 debug_only(_is_static_field_id = false;) 4313 } 4314 4315 4316 JNIid* JNIid::find(int offset) { 4317 JNIid* current = this; 4318 while (current != nullptr) { 4319 if (current->offset() == offset) return current; 4320 current = current->next(); 4321 } 4322 return nullptr; 4323 } 4324 4325 void JNIid::deallocate(JNIid* current) { 4326 while (current != nullptr) { 4327 JNIid* next = current->next(); 4328 delete current; 4329 current = next; 4330 } 4331 } 4332 4333 4334 void JNIid::verify(Klass* holder) { 4335 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 4336 int end_field_offset; 4337 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 4338 4339 JNIid* current = this; 4340 while (current != nullptr) { 4341 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 4342 #ifdef ASSERT 4343 int o = current->offset(); 4344 if (current->is_static_field_id()) { 4345 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 4346 } 4347 #endif 4348 current = current->next(); 4349 } 4350 } 4351 4352 void InstanceKlass::set_init_state(ClassState state) { 4353 #ifdef ASSERT 4354 bool good_state = is_shared() ? (_init_state <= state) 4355 : (_init_state < state); 4356 assert(good_state || state == allocated, "illegal state transition"); 4357 #endif 4358 assert(_init_thread == nullptr, "should be cleared before state change"); 4359 _init_state = state; 4360 } 4361 4362 #if INCLUDE_JVMTI 4363 4364 // RedefineClasses() support for previous versions 4365 4366 // Globally, there is at least one previous version of a class to walk 4367 // during class unloading, which is saved because old methods in the class 4368 // are still running. Otherwise the previous version list is cleaned up. 4369 bool InstanceKlass::_should_clean_previous_versions = false; 4370 4371 // Returns true if there are previous versions of a class for class 4372 // unloading only. Also resets the flag to false. purge_previous_version 4373 // will set the flag to true if there are any left, i.e., if there's any 4374 // work to do for next time. This is to avoid the expensive code cache 4375 // walk in CLDG::clean_deallocate_lists(). 4376 bool InstanceKlass::should_clean_previous_versions_and_reset() { 4377 bool ret = _should_clean_previous_versions; 4378 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s", 4379 ret ? "true" : "false"); 4380 _should_clean_previous_versions = false; 4381 return ret; 4382 } 4383 4384 // This nulls out jmethodIDs for all methods in 'klass' 4385 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up 4386 // during class unloading. 4387 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions 4388 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this 4389 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2). 4390 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID. 4391 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) { 4392 Array<Method*>* method_refs = klass->methods(); 4393 for (int k = 0; k < method_refs->length(); k++) { 4394 Method* method = method_refs->at(k); 4395 if (method != nullptr && method->is_obsolete()) { 4396 method->clear_jmethod_id(); 4397 } 4398 } 4399 } 4400 4401 // Purge previous versions before adding new previous versions of the class and 4402 // during class unloading. 4403 void InstanceKlass::purge_previous_version_list() { 4404 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 4405 assert(has_been_redefined(), "Should only be called for main class"); 4406 4407 // Quick exit. 4408 if (previous_versions() == nullptr) { 4409 return; 4410 } 4411 4412 // This klass has previous versions so see what we can cleanup 4413 // while it is safe to do so. 4414 4415 int deleted_count = 0; // leave debugging breadcrumbs 4416 int live_count = 0; 4417 ClassLoaderData* loader_data = class_loader_data(); 4418 assert(loader_data != nullptr, "should never be null"); 4419 4420 ResourceMark rm; 4421 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 4422 4423 // previous versions are linked together through the InstanceKlass 4424 InstanceKlass* pv_node = previous_versions(); 4425 InstanceKlass* last = this; 4426 int version = 0; 4427 4428 // check the previous versions list 4429 for (; pv_node != nullptr; ) { 4430 4431 ConstantPool* pvcp = pv_node->constants(); 4432 assert(pvcp != nullptr, "cp ref was unexpectedly cleared"); 4433 4434 if (!pvcp->on_stack()) { 4435 // If the constant pool isn't on stack, none of the methods 4436 // are executing. Unlink this previous_version. 4437 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 4438 // so will be deallocated during the next phase of class unloading. 4439 log_trace(redefine, class, iklass, purge) 4440 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node)); 4441 // Unlink from previous version list. 4442 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 4443 InstanceKlass* next = pv_node->previous_versions(); 4444 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class 4445 pv_node->link_previous_versions(nullptr); // point next to null 4446 last->link_previous_versions(next); 4447 // Delete this node directly. Nothing is referring to it and we don't 4448 // want it to increase the counter for metadata to delete in CLDG. 4449 MetadataFactory::free_metadata(loader_data, pv_node); 4450 pv_node = next; 4451 deleted_count++; 4452 version++; 4453 continue; 4454 } else { 4455 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder"); 4456 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 4457 live_count++; 4458 if (pvcp->is_shared()) { 4459 // Shared previous versions can never be removed so no cleaning is needed. 4460 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node)); 4461 } else { 4462 // Previous version alive, set that clean is needed for next time. 4463 _should_clean_previous_versions = true; 4464 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node)); 4465 } 4466 } 4467 4468 // next previous version 4469 last = pv_node; 4470 pv_node = pv_node->previous_versions(); 4471 version++; 4472 } 4473 log_trace(redefine, class, iklass, purge) 4474 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 4475 } 4476 4477 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 4478 int emcp_method_count) { 4479 int obsolete_method_count = old_methods->length() - emcp_method_count; 4480 4481 if (emcp_method_count != 0 && obsolete_method_count != 0 && 4482 _previous_versions != nullptr) { 4483 // We have a mix of obsolete and EMCP methods so we have to 4484 // clear out any matching EMCP method entries the hard way. 4485 int local_count = 0; 4486 for (int i = 0; i < old_methods->length(); i++) { 4487 Method* old_method = old_methods->at(i); 4488 if (old_method->is_obsolete()) { 4489 // only obsolete methods are interesting 4490 Symbol* m_name = old_method->name(); 4491 Symbol* m_signature = old_method->signature(); 4492 4493 // previous versions are linked together through the InstanceKlass 4494 int j = 0; 4495 for (InstanceKlass* prev_version = _previous_versions; 4496 prev_version != nullptr; 4497 prev_version = prev_version->previous_versions(), j++) { 4498 4499 Array<Method*>* method_refs = prev_version->methods(); 4500 for (int k = 0; k < method_refs->length(); k++) { 4501 Method* method = method_refs->at(k); 4502 4503 if (!method->is_obsolete() && 4504 method->name() == m_name && 4505 method->signature() == m_signature) { 4506 // The current RedefineClasses() call has made all EMCP 4507 // versions of this method obsolete so mark it as obsolete 4508 log_trace(redefine, class, iklass, add) 4509 ("%s(%s): flush obsolete method @%d in version @%d", 4510 m_name->as_C_string(), m_signature->as_C_string(), k, j); 4511 4512 method->set_is_obsolete(); 4513 break; 4514 } 4515 } 4516 4517 // The previous loop may not find a matching EMCP method, but 4518 // that doesn't mean that we can optimize and not go any 4519 // further back in the PreviousVersion generations. The EMCP 4520 // method for this generation could have already been made obsolete, 4521 // but there still may be an older EMCP method that has not 4522 // been made obsolete. 4523 } 4524 4525 if (++local_count >= obsolete_method_count) { 4526 // no more obsolete methods so bail out now 4527 break; 4528 } 4529 } 4530 } 4531 } 4532 } 4533 4534 // Save the scratch_class as the previous version if any of the methods are running. 4535 // The previous_versions are used to set breakpoints in EMCP methods and they are 4536 // also used to clean MethodData links to redefined methods that are no longer running. 4537 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 4538 int emcp_method_count) { 4539 assert(Thread::current()->is_VM_thread(), 4540 "only VMThread can add previous versions"); 4541 4542 ResourceMark rm; 4543 log_trace(redefine, class, iklass, add) 4544 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 4545 4546 // Clean out old previous versions for this class 4547 purge_previous_version_list(); 4548 4549 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 4550 // a previous redefinition may be made obsolete by this redefinition. 4551 Array<Method*>* old_methods = scratch_class->methods(); 4552 mark_newly_obsolete_methods(old_methods, emcp_method_count); 4553 4554 // If the constant pool for this previous version of the class 4555 // is not marked as being on the stack, then none of the methods 4556 // in this previous version of the class are on the stack so 4557 // we don't need to add this as a previous version. 4558 ConstantPool* cp_ref = scratch_class->constants(); 4559 if (!cp_ref->on_stack()) { 4560 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 4561 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 4562 return; 4563 } 4564 4565 // Add previous version if any methods are still running or if this is 4566 // a shared class which should never be removed. 4567 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version"); 4568 scratch_class->link_previous_versions(previous_versions()); 4569 link_previous_versions(scratch_class); 4570 if (cp_ref->is_shared()) { 4571 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared"); 4572 } else { 4573 // We only set clean_previous_versions flag for processing during class 4574 // unloading for non-shared classes. 4575 _should_clean_previous_versions = true; 4576 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4577 } 4578 } // end add_previous_version() 4579 4580 #endif // INCLUDE_JVMTI 4581 4582 Method* InstanceKlass::method_with_idnum(int idnum) { 4583 Method* m = nullptr; 4584 if (idnum < methods()->length()) { 4585 m = methods()->at(idnum); 4586 } 4587 if (m == nullptr || m->method_idnum() != idnum) { 4588 for (int index = 0; index < methods()->length(); ++index) { 4589 m = methods()->at(index); 4590 if (m->method_idnum() == idnum) { 4591 return m; 4592 } 4593 } 4594 // None found, return null for the caller to handle. 4595 return nullptr; 4596 } 4597 return m; 4598 } 4599 4600 4601 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 4602 if (idnum >= methods()->length()) { 4603 return nullptr; 4604 } 4605 Method* m = methods()->at(idnum); 4606 if (m != nullptr && m->orig_method_idnum() == idnum) { 4607 return m; 4608 } 4609 // Obsolete method idnum does not match the original idnum 4610 for (int index = 0; index < methods()->length(); ++index) { 4611 m = methods()->at(index); 4612 if (m->orig_method_idnum() == idnum) { 4613 return m; 4614 } 4615 } 4616 // None found, return null for the caller to handle. 4617 return nullptr; 4618 } 4619 4620 4621 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 4622 InstanceKlass* holder = get_klass_version(version); 4623 if (holder == nullptr) { 4624 return nullptr; // The version of klass is gone, no method is found 4625 } 4626 Method* method = holder->method_with_orig_idnum(idnum); 4627 return method; 4628 } 4629 4630 #if INCLUDE_JVMTI 4631 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4632 return _cached_class_file; 4633 } 4634 4635 jint InstanceKlass::get_cached_class_file_len() { 4636 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4637 } 4638 4639 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4640 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4641 } 4642 #endif 4643 4644 // Make a step iterating over the class hierarchy under the root class. 4645 // Skips subclasses if requested. 4646 void ClassHierarchyIterator::next() { 4647 assert(_current != nullptr, "required"); 4648 if (_visit_subclasses && _current->subklass() != nullptr) { 4649 _current = _current->subklass(); 4650 return; // visit next subclass 4651 } 4652 _visit_subclasses = true; // reset 4653 while (_current->next_sibling() == nullptr && _current != _root) { 4654 _current = _current->superklass(); // backtrack; no more sibling subclasses left 4655 } 4656 if (_current == _root) { 4657 // Iteration is over (back at root after backtracking). Invalidate the iterator. 4658 _current = nullptr; 4659 return; 4660 } 4661 _current = _current->next_sibling(); 4662 return; // visit next sibling subclass 4663 }