1 /* 2 * Copyright (c) 1997, 2025, 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 "cds/aotClassInitializer.hpp" 26 #include "cds/aotMetaspace.hpp" 27 #include "cds/archiveUtils.hpp" 28 #include "cds/cdsConfig.hpp" 29 #include "cds/cdsEnumKlass.hpp" 30 #include "cds/classListWriter.hpp" 31 #include "cds/heapShared.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 "klass.inline.hpp" 54 #include "logging/log.hpp" 55 #include "logging/logMessage.hpp" 56 #include "logging/logStream.hpp" 57 #include "memory/allocation.inline.hpp" 58 #include "memory/iterator.inline.hpp" 59 #include "memory/metadataFactory.hpp" 60 #include "memory/metaspaceClosure.hpp" 61 #include "memory/oopFactory.hpp" 62 #include "memory/resourceArea.hpp" 63 #include "memory/universe.hpp" 64 #include "oops/constantPool.hpp" 65 #include "oops/fieldStreams.inline.hpp" 66 #include "oops/instanceClassLoaderKlass.hpp" 67 #include "oops/instanceKlass.inline.hpp" 68 #include "oops/instanceMirrorKlass.hpp" 69 #include "oops/instanceOop.hpp" 70 #include "oops/instanceStackChunkKlass.hpp" 71 #include "oops/klass.inline.hpp" 72 #include "oops/method.hpp" 73 #include "oops/oop.inline.hpp" 74 #include "oops/recordComponent.hpp" 75 #include "oops/symbol.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/atomicAccess.hpp" 82 #include "runtime/deoptimization.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/nativeStackPrinter.hpp" 100 #include "utilities/stringUtils.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_is_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 static inline bool is_stack_chunk_class(const Symbol* class_name, 174 const ClassLoaderData* loader_data) { 175 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() && 176 loader_data->is_the_null_class_loader_data()); 177 } 178 179 // private: called to verify that k is a static member of this nest. 180 // We know that k is an instance class in the same package and hence the 181 // same classloader. 182 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const { 183 assert(!is_hidden(), "unexpected hidden class"); 184 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) { 185 if (log_is_enabled(Trace, class, nestmates)) { 186 ResourceMark rm(current); 187 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 188 k->external_name(), this->external_name()); 189 } 190 return false; 191 } 192 193 if (log_is_enabled(Trace, class, nestmates)) { 194 ResourceMark rm(current); 195 log_trace(class, nestmates)("Checking nest membership of %s in %s", 196 k->external_name(), this->external_name()); 197 } 198 199 // Check for the named class in _nest_members. 200 // We don't resolve, or load, any classes. 201 for (int i = 0; i < _nest_members->length(); i++) { 202 int cp_index = _nest_members->at(i); 203 Symbol* name = _constants->klass_name_at(cp_index); 204 if (name == k->name()) { 205 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index); 206 return true; 207 } 208 } 209 log_trace(class, nestmates)("- class is NOT a nest member!"); 210 return false; 211 } 212 213 // Called to verify that k is a permitted subclass of this class. 214 // The incoming stringStream is used to format the messages for error logging and for the caller 215 // to use for exception throwing. 216 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const { 217 Thread* current = Thread::current(); 218 assert(k != nullptr, "sanity check"); 219 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(), 220 "unexpected empty _permitted_subclasses array"); 221 222 if (log_is_enabled(Trace, class, sealed)) { 223 ResourceMark rm(current); 224 log_trace(class, sealed)("Checking for permitted subclass %s in %s", 225 k->external_name(), this->external_name()); 226 } 227 228 // Check that the class and its super are in the same module. 229 if (k->module() != this->module()) { 230 ss.print("Failed same module check: subclass %s is in module '%s' with loader %s, " 231 "and sealed class %s is in module '%s' with loader %s", 232 k->external_name(), 233 k->module()->name_as_C_string(), 234 k->module()->loader_data()->loader_name_and_id(), 235 this->external_name(), 236 this->module()->name_as_C_string(), 237 this->module()->loader_data()->loader_name_and_id()); 238 log_trace(class, sealed)(" - %s", ss.as_string()); 239 return false; 240 } 241 242 if (!k->is_public() && !is_same_class_package(k)) { 243 ss.print("Failed same package check: non-public subclass %s is in package '%s' with classloader %s, " 244 "and sealed class %s is in package '%s' with classloader %s", 245 k->external_name(), 246 k->package() != nullptr ? k->package()->name()->as_C_string() : "unnamed", 247 k->module()->loader_data()->loader_name_and_id(), 248 this->external_name(), 249 this->package() != nullptr ? this->package()->name()->as_C_string() : "unnamed", 250 this->module()->loader_data()->loader_name_and_id()); 251 log_trace(class, sealed)(" - %s", ss.as_string()); 252 return false; 253 } 254 255 for (int i = 0; i < _permitted_subclasses->length(); i++) { 256 int cp_index = _permitted_subclasses->at(i); 257 Symbol* name = _constants->klass_name_at(cp_index); 258 if (name == k->name()) { 259 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index); 260 return true; 261 } 262 } 263 264 ss.print("Failed listed permitted subclass check: class %s is not a permitted subclass of %s", 265 k->external_name(), this->external_name()); 266 log_trace(class, sealed)(" - %s", ss.as_string()); 267 return false; 268 } 269 270 // Return nest-host class, resolving, validating and saving it if needed. 271 // In cases where this is called from a thread that cannot do classloading 272 // (such as a native JIT thread) then we simply return null, which in turn 273 // causes the access check to return false. Such code will retry the access 274 // from a more suitable environment later. Otherwise the _nest_host is always 275 // set once this method returns. 276 // Any errors from nest-host resolution must be preserved so they can be queried 277 // from higher-level access checking code, and reported as part of access checking 278 // exceptions. 279 // VirtualMachineErrors are propagated with a null return. 280 // Under any conditions where the _nest_host can be set to non-null the resulting 281 // value of it and, if applicable, the nest host resolution/validation error, 282 // are idempotent. 283 InstanceKlass* InstanceKlass::nest_host(TRAPS) { 284 InstanceKlass* nest_host_k = _nest_host; 285 if (nest_host_k != nullptr) { 286 return nest_host_k; 287 } 288 289 ResourceMark rm(THREAD); 290 291 // need to resolve and save our nest-host class. 292 if (_nest_host_index != 0) { // we have a real nest_host 293 // Before trying to resolve check if we're in a suitable context 294 bool can_resolve = THREAD->can_call_java(); 295 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) { 296 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 297 this->external_name()); 298 return nullptr; // sentinel to say "try again from a different context" 299 } 300 301 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 302 this->external_name(), 303 _constants->klass_name_at(_nest_host_index)->as_C_string()); 304 305 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 306 if (HAS_PENDING_EXCEPTION) { 307 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) { 308 return nullptr; // propagate VMEs 309 } 310 stringStream ss; 311 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string(); 312 ss.print("Nest host resolution of %s with host %s failed: ", 313 this->external_name(), target_host_class); 314 java_lang_Throwable::print(PENDING_EXCEPTION, &ss); 315 constantPoolHandle cph(THREAD, constants()); 316 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss); 317 CLEAR_PENDING_EXCEPTION; 318 319 log_trace(class, nestmates)("%s", ss.base()); 320 } else { 321 // A valid nest-host is an instance class in the current package that lists this 322 // class as a nest member. If any of these conditions are not met the class is 323 // its own nest-host. 324 const char* error = nullptr; 325 326 // JVMS 5.4.4 indicates package check comes first 327 if (is_same_class_package(k)) { 328 // Now check actual membership. We can't be a member if our "host" is 329 // not an instance class. 330 if (k->is_instance_klass()) { 331 nest_host_k = InstanceKlass::cast(k); 332 bool is_member = nest_host_k->has_nest_member(THREAD, this); 333 if (is_member) { 334 _nest_host = nest_host_k; // save resolved nest-host value 335 336 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 337 this->external_name(), k->external_name()); 338 return nest_host_k; 339 } else { 340 error = "current type is not listed as a nest member"; 341 } 342 } else { 343 error = "host is not an instance class"; 344 } 345 } else { 346 error = "types are in different packages"; 347 } 348 349 // something went wrong, so record what and log it 350 { 351 stringStream ss; 352 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s", 353 this->external_name(), 354 this->class_loader_data()->loader_name_and_id(), 355 k->external_name(), 356 k->class_loader_data()->loader_name_and_id(), 357 error); 358 constantPoolHandle cph(THREAD, constants()); 359 SystemDictionary::add_nest_host_error(cph, _nest_host_index, ss); 360 log_trace(class, nestmates)("%s", ss.base()); 361 } 362 } 363 } else { 364 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 365 this->external_name()); 366 } 367 368 // Either not in an explicit nest, or else an error occurred, so 369 // the nest-host is set to `this`. Any thread that sees this assignment 370 // will also see any setting of nest_host_error(), if applicable. 371 return (_nest_host = this); 372 } 373 374 // Dynamic nest member support: set this class's nest host to the given class. 375 // This occurs as part of the class definition, as soon as the instanceKlass 376 // has been created and doesn't require further resolution. The code: 377 // lookup().defineHiddenClass(bytes_for_X, NESTMATE); 378 // results in: 379 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost()) 380 // If it has an explicit _nest_host_index or _nest_members, these will be ignored. 381 // We also know the "host" is a valid nest-host in the same package so we can 382 // assert some of those facts. 383 void InstanceKlass::set_nest_host(InstanceKlass* host) { 384 assert(is_hidden(), "must be a hidden class"); 385 assert(host != nullptr, "null nest host specified"); 386 assert(_nest_host == nullptr, "current class has resolved nest-host"); 387 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s", 388 nest_host_error()); 389 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) || 390 (host->_nest_host == host), "proposed host is not a valid nest-host"); 391 // Can't assert this as package is not set yet: 392 // assert(is_same_class_package(host), "proposed host is in wrong package"); 393 394 if (log_is_enabled(Trace, class, nestmates)) { 395 ResourceMark rm; 396 const char* msg = ""; 397 // a hidden class does not expect a statically defined nest-host 398 if (_nest_host_index > 0) { 399 msg = "(the NestHost attribute in the current class is ignored)"; 400 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) { 401 msg = "(the NestMembers attribute in the current class is ignored)"; 402 } 403 log_trace(class, nestmates)("Injected type %s into the nest of %s %s", 404 this->external_name(), 405 host->external_name(), 406 msg); 407 } 408 // set dynamic nest host 409 _nest_host = host; 410 // Record dependency to keep nest host from being unloaded before this class. 411 ClassLoaderData* this_key = class_loader_data(); 412 assert(this_key != nullptr, "sanity"); 413 this_key->record_dependency(host); 414 } 415 416 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 417 // or we are k's nest_host - all of which is covered by comparing the two 418 // resolved_nest_hosts. 419 // Any exceptions (i.e. VMEs) are propagated. 420 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 421 422 assert(this != k, "this should be handled by higher-level code"); 423 424 // Per JVMS 5.4.4 we first resolve and validate the current class, then 425 // the target class k. 426 427 InstanceKlass* cur_host = nest_host(CHECK_false); 428 if (cur_host == nullptr) { 429 return false; 430 } 431 432 Klass* k_nest_host = k->nest_host(CHECK_false); 433 if (k_nest_host == nullptr) { 434 return false; 435 } 436 437 bool access = (cur_host == k_nest_host); 438 439 ResourceMark rm(THREAD); 440 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 441 this->external_name(), 442 access ? "" : "NOT ", 443 k->external_name()); 444 return access; 445 } 446 447 const char* InstanceKlass::nest_host_error() { 448 if (_nest_host_index == 0) { 449 return nullptr; 450 } else { 451 constantPoolHandle cph(Thread::current(), constants()); 452 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index); 453 } 454 } 455 456 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 457 const int size = InstanceKlass::size(parser.vtable_size(), 458 parser.itable_size(), 459 nonstatic_oop_map_size(parser.total_oop_map_count()), 460 parser.is_interface()); 461 462 const Symbol* const class_name = parser.class_name(); 463 assert(class_name != nullptr, "invariant"); 464 ClassLoaderData* loader_data = parser.loader_data(); 465 assert(loader_data != nullptr, "invariant"); 466 467 InstanceKlass* ik; 468 469 // Allocation 470 if (parser.is_instance_ref_klass()) { 471 // java.lang.ref.Reference 472 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 473 } else if (class_name == vmSymbols::java_lang_Class()) { 474 // mirror - java.lang.Class 475 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 476 } else if (is_stack_chunk_class(class_name, loader_data)) { 477 // stack chunk 478 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser); 479 } else if (is_class_loader(class_name, parser)) { 480 // class loader - java.lang.ClassLoader 481 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 482 } else { 483 // normal 484 ik = new (loader_data, size, THREAD) InstanceKlass(parser); 485 } 486 487 if (ik != nullptr && UseCompressedClassPointers) { 488 assert(CompressedKlassPointers::is_encodable(ik), 489 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik)); 490 } 491 492 // Check for pending exception before adding to the loader data and incrementing 493 // class count. Can get OOM here. 494 if (HAS_PENDING_EXCEPTION) { 495 return nullptr; 496 } 497 498 return ik; 499 } 500 501 502 // copy method ordering from resource area to Metaspace 503 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 504 if (m != nullptr) { 505 // allocate a new array and copy contents (memcpy?) 506 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 507 for (int i = 0; i < m->length(); i++) { 508 _method_ordering->at_put(i, m->at(i)); 509 } 510 } else { 511 _method_ordering = Universe::the_empty_int_array(); 512 } 513 } 514 515 // create a new array of vtable_indices for default methods 516 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 517 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 518 assert(default_vtable_indices() == nullptr, "only create once"); 519 set_default_vtable_indices(vtable_indices); 520 return vtable_indices; 521 } 522 523 524 InstanceKlass::InstanceKlass() { 525 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS"); 526 } 527 528 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) : 529 Klass(kind), 530 _nest_members(nullptr), 531 _nest_host(nullptr), 532 _permitted_subclasses(nullptr), 533 _record_components(nullptr), 534 _static_field_size(parser.static_field_size()), 535 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 536 _itable_len(parser.itable_size()), 537 _nest_host_index(0), 538 _init_state(allocated), 539 _reference_type(reference_type), 540 _init_thread(nullptr) 541 { 542 set_vtable_length(parser.vtable_size()); 543 set_access_flags(parser.access_flags()); 544 if (parser.is_hidden()) set_is_hidden(); 545 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 546 false)); 547 548 assert(nullptr == _methods, "underlying memory not zeroed?"); 549 assert(is_instance_klass(), "is layout incorrect?"); 550 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 551 } 552 553 void InstanceKlass::set_is_cloneable() { 554 if (name() == vmSymbols::java_lang_invoke_MemberName()) { 555 assert(is_final(), "no subclasses allowed"); 556 // MemberName cloning should not be intrinsified and always happen in JVM_Clone. 557 } else if (reference_type() != REF_NONE) { 558 // Reference cloning should not be intrinsified and always happen in JVM_Clone. 559 } else { 560 set_is_cloneable_fast(); 561 } 562 } 563 564 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 565 Array<Method*>* methods) { 566 if (methods != nullptr && methods != Universe::the_empty_method_array() && 567 !methods->in_aot_cache()) { 568 for (int i = 0; i < methods->length(); i++) { 569 Method* method = methods->at(i); 570 if (method == nullptr) continue; // maybe null if error processing 571 // Only want to delete methods that are not executing for RedefineClasses. 572 // The previous version will point to them so they're not totally dangling 573 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 574 MetadataFactory::free_metadata(loader_data, method); 575 } 576 MetadataFactory::free_array<Method*>(loader_data, methods); 577 } 578 } 579 580 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 581 const InstanceKlass* super_klass, 582 Array<InstanceKlass*>* local_interfaces, 583 Array<InstanceKlass*>* transitive_interfaces) { 584 // Only deallocate transitive interfaces if not empty, same as super class 585 // or same as local interfaces. See code in parseClassFile. 586 Array<InstanceKlass*>* ti = transitive_interfaces; 587 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 588 // check that the interfaces don't come from super class 589 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr : 590 super_klass->transitive_interfaces(); 591 if (ti != sti && ti != nullptr && !ti->in_aot_cache()) { 592 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 593 } 594 } 595 596 // local interfaces can be empty 597 if (local_interfaces != Universe::the_empty_instance_klass_array() && 598 local_interfaces != nullptr && !local_interfaces->in_aot_cache()) { 599 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 600 } 601 } 602 603 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 604 Array<RecordComponent*>* record_components) { 605 if (record_components != nullptr && !record_components->in_aot_cache()) { 606 for (int i = 0; i < record_components->length(); i++) { 607 RecordComponent* record_component = record_components->at(i); 608 MetadataFactory::free_metadata(loader_data, record_component); 609 } 610 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 611 } 612 } 613 614 // This function deallocates the metadata and C heap pointers that the 615 // InstanceKlass points to. 616 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 617 // Orphan the mirror first, CMS thinks it's still live. 618 if (java_mirror() != nullptr) { 619 java_lang_Class::set_klass(java_mirror(), nullptr); 620 } 621 622 // Also remove mirror from handles 623 loader_data->remove_handle(_java_mirror); 624 625 // Need to take this class off the class loader data list. 626 loader_data->remove_class(this); 627 628 // The array_klass for this class is created later, after error handling. 629 // For class redefinition, we keep the original class so this scratch class 630 // doesn't have an array class. Either way, assert that there is nothing 631 // to deallocate. 632 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet"); 633 634 // Release C heap allocated data that this points to, which includes 635 // reference counting symbol names. 636 // Can't release the constant pool or MethodData C heap data here because the constant 637 // pool can be deallocated separately from the InstanceKlass for default methods and 638 // redefine classes. MethodData can also be released separately. 639 release_C_heap_structures(/* release_sub_metadata */ false); 640 641 deallocate_methods(loader_data, methods()); 642 set_methods(nullptr); 643 644 deallocate_record_components(loader_data, record_components()); 645 set_record_components(nullptr); 646 647 if (method_ordering() != nullptr && 648 method_ordering() != Universe::the_empty_int_array() && 649 !method_ordering()->in_aot_cache()) { 650 MetadataFactory::free_array<int>(loader_data, method_ordering()); 651 } 652 set_method_ordering(nullptr); 653 654 // default methods can be empty 655 if (default_methods() != nullptr && 656 default_methods() != Universe::the_empty_method_array() && 657 !default_methods()->in_aot_cache()) { 658 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 659 } 660 // Do NOT deallocate the default methods, they are owned by superinterfaces. 661 set_default_methods(nullptr); 662 663 // default methods vtable indices can be empty 664 if (default_vtable_indices() != nullptr && 665 !default_vtable_indices()->in_aot_cache()) { 666 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 667 } 668 set_default_vtable_indices(nullptr); 669 670 671 // This array is in Klass, but remove it with the InstanceKlass since 672 // this place would be the only caller and it can share memory with transitive 673 // interfaces. 674 if (secondary_supers() != nullptr && 675 secondary_supers() != Universe::the_empty_klass_array() && 676 // see comments in compute_secondary_supers about the following cast 677 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 678 !secondary_supers()->in_aot_cache()) { 679 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 680 } 681 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY); 682 683 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 684 set_transitive_interfaces(nullptr); 685 set_local_interfaces(nullptr); 686 687 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->in_aot_cache()) { 688 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream()); 689 } 690 set_fieldinfo_stream(nullptr); 691 692 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->in_aot_cache()) { 693 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table()); 694 } 695 set_fieldinfo_search_table(nullptr); 696 697 if (fields_status() != nullptr && !fields_status()->in_aot_cache()) { 698 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status()); 699 } 700 set_fields_status(nullptr); 701 702 // If a method from a redefined class is using this constant pool, don't 703 // delete it, yet. The new class's previous version will point to this. 704 if (constants() != nullptr) { 705 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 706 if (!constants()->in_aot_cache()) { 707 MetadataFactory::free_metadata(loader_data, constants()); 708 } 709 // Delete any cached resolution errors for the constant pool 710 SystemDictionary::delete_resolution_error(constants()); 711 712 set_constants(nullptr); 713 } 714 715 if (inner_classes() != nullptr && 716 inner_classes() != Universe::the_empty_short_array() && 717 !inner_classes()->in_aot_cache()) { 718 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 719 } 720 set_inner_classes(nullptr); 721 722 if (nest_members() != nullptr && 723 nest_members() != Universe::the_empty_short_array() && 724 !nest_members()->in_aot_cache()) { 725 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 726 } 727 set_nest_members(nullptr); 728 729 if (permitted_subclasses() != nullptr && 730 permitted_subclasses() != Universe::the_empty_short_array() && 731 !permitted_subclasses()->in_aot_cache()) { 732 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses()); 733 } 734 set_permitted_subclasses(nullptr); 735 736 // We should deallocate the Annotations instance if it's not in shared spaces. 737 if (annotations() != nullptr && !annotations()->in_aot_cache()) { 738 MetadataFactory::free_metadata(loader_data, annotations()); 739 } 740 set_annotations(nullptr); 741 742 SystemDictionaryShared::handle_class_unloading(this); 743 744 #if INCLUDE_CDS_JAVA_HEAP 745 if (CDSConfig::is_dumping_heap()) { 746 HeapShared::remove_scratch_objects(this); 747 } 748 #endif 749 } 750 751 bool InstanceKlass::is_record() const { 752 return _record_components != nullptr && 753 is_final() && 754 super() == vmClasses::Record_klass(); 755 } 756 757 bool InstanceKlass::is_sealed() const { 758 return _permitted_subclasses != nullptr && 759 _permitted_subclasses != Universe::the_empty_short_array(); 760 } 761 762 // JLS 8.9: An enum class is either implicitly final and derives 763 // from java.lang.Enum, or else is implicitly sealed to its 764 // anonymous subclasses. This query detects both kinds. 765 // It does not validate the finality or 766 // sealing conditions: it merely checks for a super of Enum. 767 // This is sufficient for recognizing well-formed enums. 768 bool InstanceKlass::is_enum_subclass() const { 769 InstanceKlass* s = super(); 770 return (s == vmClasses::Enum_klass() || 771 (s != nullptr && s->super() == vmClasses::Enum_klass())); 772 } 773 774 bool InstanceKlass::should_be_initialized() const { 775 return !is_initialized(); 776 } 777 778 klassItable InstanceKlass::itable() const { 779 return klassItable(const_cast<InstanceKlass*>(this)); 780 } 781 782 // JVMTI spec thinks there are signers and protection domain in the 783 // instanceKlass. These accessors pretend these fields are there. 784 // The hprof specification also thinks these fields are in InstanceKlass. 785 oop InstanceKlass::protection_domain() const { 786 // return the protection_domain from the mirror 787 return java_lang_Class::protection_domain(java_mirror()); 788 } 789 790 objArrayOop InstanceKlass::signers() const { 791 // return the signers from the mirror 792 return java_lang_Class::signers(java_mirror()); 793 } 794 795 oop InstanceKlass::init_lock() const { 796 // return the init lock from the mirror 797 oop lock = java_lang_Class::init_lock(java_mirror()); 798 // Prevent reordering with any access of initialization state 799 OrderAccess::loadload(); 800 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state 801 "only fully initialized state can have a null lock"); 802 return lock; 803 } 804 805 // Set the initialization lock to null so the object can be GC'ed. Any racing 806 // threads to get this lock will see a null lock and will not lock. 807 // That's okay because they all check for initialized state after getting 808 // the lock and return. For preempted vthreads we keep the oop protected 809 // in the ObjectMonitor (see ObjectMonitor::set_object_strong()). 810 void InstanceKlass::fence_and_clear_init_lock() { 811 // make sure previous stores are all done, notably the init_state. 812 OrderAccess::storestore(); 813 java_lang_Class::clear_init_lock(java_mirror()); 814 assert(!is_not_initialized(), "class must be initialized now"); 815 } 816 817 class PreemptableInitCall { 818 JavaThread* _thread; 819 bool _previous; 820 DEBUG_ONLY(InstanceKlass* _previous_klass;) 821 public: 822 PreemptableInitCall(JavaThread* thread, InstanceKlass* ik) : _thread(thread) { 823 _previous = thread->at_preemptable_init(); 824 _thread->set_at_preemptable_init(true); 825 DEBUG_ONLY(_previous_klass = _thread->preempt_init_klass();) 826 DEBUG_ONLY(_thread->set_preempt_init_klass(ik)); 827 } 828 ~PreemptableInitCall() { 829 _thread->set_at_preemptable_init(_previous); 830 DEBUG_ONLY(_thread->set_preempt_init_klass(_previous_klass)); 831 } 832 }; 833 834 void InstanceKlass::initialize_preemptable(TRAPS) { 835 if (this->should_be_initialized()) { 836 PreemptableInitCall pic(THREAD, this); 837 initialize_impl(THREAD); 838 } else { 839 assert(is_initialized(), "sanity check"); 840 } 841 } 842 843 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 844 // process. The step comments refers to the procedure described in that section. 845 // Note: implementation moved to static method to expose the this pointer. 846 void InstanceKlass::initialize(TRAPS) { 847 if (this->should_be_initialized()) { 848 initialize_impl(CHECK); 849 // Note: at this point the class may be initialized 850 // OR it may be in the state of being initialized 851 // in case of recursive initialization! 852 } else { 853 assert(is_initialized(), "sanity check"); 854 } 855 } 856 857 #ifdef ASSERT 858 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const { 859 assert(has_aot_initialized_mirror(), "must be"); 860 861 InstanceKlass* s = super(); 862 if (s != nullptr) { 863 DEBUG_ONLY(ResourceMark rm); 864 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized", 865 s->external_name(), external_name()); 866 s->assert_no_clinit_will_run_for_aot_initialized_class(); 867 } 868 869 Array<InstanceKlass*>* interfaces = local_interfaces(); 870 int len = interfaces->length(); 871 for (int i = 0; i < len; i++) { 872 InstanceKlass* intf = interfaces->at(i); 873 if (!intf->is_initialized()) { 874 ResourceMark rm; 875 // Note: an interface needs to be marked as is_initialized() only if 876 // - it has a <clinit> 877 // - it has declared a default method. 878 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false), 879 "uninitialized super interface %s of aot-inited class %s must not have <clinit>", 880 intf->external_name(), external_name()); 881 } 882 } 883 } 884 #endif 885 886 #if INCLUDE_CDS 887 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) { 888 assert(has_aot_initialized_mirror(), "must be"); 889 assert(CDSConfig::is_loading_heap(), "must be"); 890 assert(CDSConfig::is_using_aot_linked_classes(), "must be"); 891 assert_no_clinit_will_run_for_aot_initialized_class(); 892 893 if (is_initialized()) { 894 return; 895 } 896 897 if (is_runtime_setup_required()) { 898 // Need to take the slow path, which will call the runtimeSetup() function instead 899 // of <clinit> 900 initialize(CHECK); 901 return; 902 } 903 if (log_is_enabled(Info, aot, init)) { 904 ResourceMark rm; 905 log_info(aot, init)("%s (aot-inited)", external_name()); 906 } 907 908 link_class(CHECK); 909 910 #ifdef ASSERT 911 { 912 Handle h_init_lock(THREAD, init_lock()); 913 ObjectLocker ol(h_init_lock, THREAD); 914 assert(!is_initialized(), "sanity"); 915 assert(!is_being_initialized(), "sanity"); 916 assert(!is_in_error_state(), "sanity"); 917 } 918 #endif 919 920 set_init_thread(THREAD); 921 set_initialization_state_and_notify(fully_initialized, CHECK); 922 } 923 #endif 924 925 bool InstanceKlass::verify_code(TRAPS) { 926 // 1) Verify the bytecodes 927 return Verifier::verify(this, should_verify_class(), THREAD); 928 } 929 930 void InstanceKlass::link_class(TRAPS) { 931 assert(is_loaded(), "must be loaded"); 932 if (!is_linked()) { 933 link_class_impl(CHECK); 934 } 935 } 936 937 // Called to verify that a class can link during initialization, without 938 // throwing a VerifyError. 939 bool InstanceKlass::link_class_or_fail(TRAPS) { 940 assert(is_loaded(), "must be loaded"); 941 if (!is_linked()) { 942 link_class_impl(CHECK_false); 943 } 944 return is_linked(); 945 } 946 947 bool InstanceKlass::link_class_impl(TRAPS) { 948 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) { 949 // This is for CDS static dump only -- we use the in_error_state to indicate that 950 // the class has failed verification. Throwing the NoClassDefFoundError here is just 951 // a convenient way to stop repeat attempts to verify the same (bad) class. 952 // 953 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 954 // if we are executing Java code. This is not a problem for CDS dumping phase since 955 // it doesn't execute any Java code. 956 ResourceMark rm(THREAD); 957 // Names are all known to be < 64k so we know this formatted message is not excessively large. 958 Exceptions::fthrow(THREAD_AND_LOCATION, 959 vmSymbols::java_lang_NoClassDefFoundError(), 960 "Class %s, or one of its supertypes, failed class initialization", 961 external_name()); 962 return false; 963 } 964 // return if already verified 965 if (is_linked()) { 966 return true; 967 } 968 969 // Timing 970 // timer handles recursion 971 JavaThread* jt = THREAD; 972 973 // link super class before linking this class 974 InstanceKlass* super_klass = super(); 975 if (super_klass != nullptr) { 976 if (super_klass->is_interface()) { // check if super class is an interface 977 ResourceMark rm(THREAD); 978 // Names are all known to be < 64k so we know this formatted message is not excessively large. 979 Exceptions::fthrow( 980 THREAD_AND_LOCATION, 981 vmSymbols::java_lang_IncompatibleClassChangeError(), 982 "class %s has interface %s as super class", 983 external_name(), 984 super_klass->external_name() 985 ); 986 return false; 987 } 988 989 super_klass->link_class_impl(CHECK_false); 990 } 991 992 // link all interfaces implemented by this class before linking this class 993 Array<InstanceKlass*>* interfaces = local_interfaces(); 994 int num_interfaces = interfaces->length(); 995 for (int index = 0; index < num_interfaces; index++) { 996 InstanceKlass* interk = interfaces->at(index); 997 interk->link_class_impl(CHECK_false); 998 } 999 1000 // in case the class is linked in the process of linking its superclasses 1001 if (is_linked()) { 1002 return true; 1003 } 1004 1005 // trace only the link time for this klass that includes 1006 // the verification time 1007 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 1008 ClassLoader::perf_class_link_selftime(), 1009 ClassLoader::perf_classes_linked(), 1010 jt->get_thread_stat()->perf_recursion_counts_addr(), 1011 jt->get_thread_stat()->perf_timers_addr(), 1012 PerfClassTraceTime::CLASS_LINK); 1013 1014 // verification & rewriting 1015 { 1016 HandleMark hm(THREAD); 1017 Handle h_init_lock(THREAD, init_lock()); 1018 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false); 1019 // Don't allow preemption if we link/initialize classes below, 1020 // since that would release this monitor while we are in the 1021 // middle of linking this class. 1022 NoPreemptMark npm(THREAD); 1023 1024 // rewritten will have been set if loader constraint error found 1025 // on an earlier link attempt 1026 // don't verify or rewrite if already rewritten 1027 // 1028 1029 if (!is_linked()) { 1030 if (!is_rewritten()) { 1031 if (in_aot_cache()) { 1032 assert(!verified_at_dump_time(), "must be"); 1033 } 1034 { 1035 bool verify_ok = verify_code(THREAD); 1036 if (!verify_ok) { 1037 return false; 1038 } 1039 } 1040 1041 // Just in case a side-effect of verify linked this class already 1042 // (which can sometimes happen since the verifier loads classes 1043 // using custom class loaders, which are free to initialize things) 1044 if (is_linked()) { 1045 return true; 1046 } 1047 1048 // also sets rewritten 1049 rewrite_class(CHECK_false); 1050 } else if (in_aot_cache()) { 1051 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 1052 } 1053 1054 // relocate jsrs and link methods after they are all rewritten 1055 link_methods(CHECK_false); 1056 1057 // Initialize the vtable and interface table after 1058 // methods have been rewritten since rewrite may 1059 // fabricate new Method*s. 1060 // also does loader constraint checking 1061 // 1062 // initialize_vtable and initialize_itable need to be rerun 1063 // for a shared class if 1064 // 1) the class is loaded by custom class loader or 1065 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or 1066 // 3) the class was not verified during dump time 1067 bool need_init_table = true; 1068 if (in_aot_cache() && verified_at_dump_time() && 1069 SystemDictionaryShared::check_linking_constraints(THREAD, this)) { 1070 need_init_table = false; 1071 } 1072 if (need_init_table) { 1073 vtable().initialize_vtable_and_check_constraints(CHECK_false); 1074 itable().initialize_itable_and_check_constraints(CHECK_false); 1075 } 1076 #ifdef ASSERT 1077 vtable().verify(tty, true); 1078 // In case itable verification is ever added. 1079 // itable().verify(tty, true); 1080 #endif 1081 if (Universe::is_fully_initialized()) { 1082 DeoptimizationScope deopt_scope; 1083 { 1084 // Now mark all code that assumes the class is not linked. 1085 // Set state under the Compile_lock also. 1086 MutexLocker ml(THREAD, Compile_lock); 1087 1088 set_init_state(linked); 1089 CodeCache::mark_dependents_on(&deopt_scope, this); 1090 } 1091 // Perform the deopt handshake outside Compile_lock. 1092 deopt_scope.deoptimize_marked(); 1093 } else { 1094 set_init_state(linked); 1095 } 1096 if (JvmtiExport::should_post_class_prepare()) { 1097 JvmtiExport::post_class_prepare(THREAD, this); 1098 } 1099 } 1100 } 1101 return true; 1102 } 1103 1104 // Rewrite the byte codes of all of the methods of a class. 1105 // The rewriter must be called exactly once. Rewriting must happen after 1106 // verification but before the first method of the class is executed. 1107 void InstanceKlass::rewrite_class(TRAPS) { 1108 assert(is_loaded(), "must be loaded"); 1109 if (is_rewritten()) { 1110 assert(in_aot_cache(), "rewriting an unshared class?"); 1111 return; 1112 } 1113 Rewriter::rewrite(this, CHECK); 1114 set_rewritten(); 1115 } 1116 1117 // Now relocate and link method entry points after class is rewritten. 1118 // This is outside is_rewritten flag. In case of an exception, it can be 1119 // executed more than once. 1120 void InstanceKlass::link_methods(TRAPS) { 1121 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time()); 1122 1123 int len = methods()->length(); 1124 for (int i = len-1; i >= 0; i--) { 1125 methodHandle m(THREAD, methods()->at(i)); 1126 1127 // Set up method entry points for compiler and interpreter . 1128 m->link_method(m, CHECK); 1129 } 1130 } 1131 1132 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 1133 void InstanceKlass::initialize_super_interfaces(TRAPS) { 1134 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 1135 for (int i = 0; i < local_interfaces()->length(); ++i) { 1136 InstanceKlass* ik = local_interfaces()->at(i); 1137 1138 // Initialization is depth first search ie. we start with top of the inheritance tree 1139 // has_nonstatic_concrete_methods drives searching superinterfaces since it 1140 // means has_nonstatic_concrete_methods in its superinterface hierarchy 1141 if (ik->has_nonstatic_concrete_methods()) { 1142 ik->initialize_super_interfaces(CHECK); 1143 } 1144 1145 // Only initialize() interfaces that "declare" concrete methods. 1146 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 1147 ik->initialize(CHECK); 1148 } 1149 } 1150 } 1151 1152 using InitializationErrorTable = HashTable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>; 1153 static InitializationErrorTable* _initialization_error_table; 1154 1155 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) { 1156 // Create the same exception with a message indicating the thread name, 1157 // and the StackTraceElements. 1158 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception); 1159 ResourceMark rm(current); 1160 if (init_error.is_null()) { 1161 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name()); 1162 1163 // We failed to create the new exception, most likely due to either out-of-memory or 1164 // a stackoverflow error. If the original exception was either of those then we save 1165 // the shared, pre-allocated, stackless, instance of that exception. 1166 if (exception->klass() == vmClasses::StackOverflowError_klass()) { 1167 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name()); 1168 init_error = Handle(current, Universe::class_init_stack_overflow_error()); 1169 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) { 1170 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name()); 1171 init_error = Handle(current, Universe::class_init_out_of_memory_error()); 1172 } else { 1173 return; 1174 } 1175 } 1176 1177 MutexLocker ml(current, ClassInitError_lock); 1178 OopHandle elem = OopHandle(Universe::vm_global(), init_error()); 1179 bool created; 1180 if (_initialization_error_table == nullptr) { 1181 _initialization_error_table = new (mtClass) InitializationErrorTable(); 1182 } 1183 _initialization_error_table->put_if_absent(this, elem, &created); 1184 assert(created, "Initialization is single threaded"); 1185 log_trace(class, init)("Initialization error added for class %s", external_name()); 1186 } 1187 1188 oop InstanceKlass::get_initialization_error(JavaThread* current) { 1189 MutexLocker ml(current, ClassInitError_lock); 1190 if (_initialization_error_table == nullptr) { 1191 return nullptr; 1192 } 1193 OopHandle* h = _initialization_error_table->get(this); 1194 return (h != nullptr) ? h->resolve() : nullptr; 1195 } 1196 1197 // Need to remove entries for unloaded classes. 1198 void InstanceKlass::clean_initialization_error_table() { 1199 struct InitErrorTableCleaner { 1200 bool do_entry(const InstanceKlass* ik, OopHandle h) { 1201 if (!ik->is_loader_alive()) { 1202 h.release(Universe::vm_global()); 1203 return true; 1204 } else { 1205 return false; 1206 } 1207 } 1208 }; 1209 1210 assert_locked_or_safepoint(ClassInitError_lock); 1211 InitErrorTableCleaner cleaner; 1212 if (_initialization_error_table != nullptr) { 1213 _initialization_error_table->unlink(&cleaner); 1214 } 1215 } 1216 1217 class ThreadWaitingForClassInit : public StackObj { 1218 JavaThread* _thread; 1219 public: 1220 ThreadWaitingForClassInit(JavaThread* thread, InstanceKlass* ik) : _thread(thread) { 1221 _thread->set_class_to_be_initialized(ik); 1222 } 1223 ~ThreadWaitingForClassInit() { 1224 _thread->set_class_to_be_initialized(nullptr); 1225 } 1226 }; 1227 1228 void InstanceKlass::initialize_impl(TRAPS) { 1229 HandleMark hm(THREAD); 1230 1231 // Make sure klass is linked (verified) before initialization 1232 // A class could already be verified, since it has been reflected upon. 1233 link_class(CHECK); 1234 1235 DTRACE_CLASSINIT_PROBE(required, -1); 1236 1237 bool wait = false; 1238 1239 JavaThread* jt = THREAD; 1240 1241 bool debug_logging_enabled = log_is_enabled(Debug, class, init); 1242 1243 // refer to the JVM book page 47 for description of steps 1244 // Step 1 1245 { 1246 Handle h_init_lock(THREAD, init_lock()); 1247 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE); 1248 1249 // Step 2 1250 // If we were to use wait() instead of waitInterruptibly() then 1251 // we might end up throwing IE from link/symbol resolution sites 1252 // that aren't expected to throw. This would wreak havoc. See 6320309. 1253 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1254 if (debug_logging_enabled) { 1255 ResourceMark rm(jt); 1256 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"", 1257 jt->name(), external_name(), init_thread_name()); 1258 } 1259 wait = true; 1260 ThreadWaitingForClassInit twcl(THREAD, this); 1261 ol.wait_uninterruptibly(CHECK_PREEMPTABLE); 1262 } 1263 1264 // Step 3 1265 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1266 if (debug_logging_enabled) { 1267 ResourceMark rm(jt); 1268 log_debug(class, init)("Thread \"%s\" recursively initializing %s", 1269 jt->name(), external_name()); 1270 } 1271 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1272 return; 1273 } 1274 1275 // Step 4 1276 if (is_initialized()) { 1277 if (debug_logging_enabled) { 1278 ResourceMark rm(jt); 1279 log_debug(class, init)("Thread \"%s\" found %s already initialized", 1280 jt->name(), external_name()); 1281 } 1282 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1283 return; 1284 } 1285 1286 // Step 5 1287 if (is_in_error_state()) { 1288 if (debug_logging_enabled) { 1289 ResourceMark rm(jt); 1290 log_debug(class, init)("Thread \"%s\" found %s is in error state", 1291 jt->name(), external_name()); 1292 } 1293 1294 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1295 ResourceMark rm(THREAD); 1296 Handle cause(THREAD, get_initialization_error(THREAD)); 1297 1298 stringStream ss; 1299 ss.print("Could not initialize class %s", external_name()); 1300 if (cause.is_null()) { 1301 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string()); 1302 } else { 1303 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(), 1304 ss.as_string(), cause); 1305 } 1306 } else { 1307 1308 // Step 6 1309 set_init_state(being_initialized); 1310 set_init_thread(jt); 1311 if (debug_logging_enabled) { 1312 ResourceMark rm(jt); 1313 log_debug(class, init)("Thread \"%s\" is initializing %s", 1314 jt->name(), external_name()); 1315 } 1316 } 1317 } 1318 1319 // Block preemption once we are the initializer thread. Unmounting now 1320 // would complicate the reentrant case (identity is platform thread). 1321 NoPreemptMark npm(THREAD); 1322 1323 // Step 7 1324 // Next, if C is a class rather than an interface, initialize it's super class and super 1325 // interfaces. 1326 if (!is_interface()) { 1327 Klass* super_klass = super(); 1328 if (super_klass != nullptr && super_klass->should_be_initialized()) { 1329 super_klass->initialize(THREAD); 1330 } 1331 // If C implements any interface that declares a non-static, concrete method, 1332 // the initialization of C triggers initialization of its super interfaces. 1333 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1334 // having a superinterface that declares, non-static, concrete methods 1335 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1336 initialize_super_interfaces(THREAD); 1337 } 1338 1339 // If any exceptions, complete abruptly, throwing the same exception as above. 1340 if (HAS_PENDING_EXCEPTION) { 1341 Handle e(THREAD, PENDING_EXCEPTION); 1342 CLEAR_PENDING_EXCEPTION; 1343 { 1344 EXCEPTION_MARK; 1345 add_initialization_error(THREAD, e); 1346 // Locks object, set state, and notify all waiting threads 1347 set_initialization_state_and_notify(initialization_error, THREAD); 1348 CLEAR_PENDING_EXCEPTION; 1349 } 1350 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1351 THROW_OOP(e()); 1352 } 1353 } 1354 1355 1356 // Step 8 1357 { 1358 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1359 if (class_initializer() != nullptr) { 1360 // Timer includes any side effects of class initialization (resolution, 1361 // etc), but not recursive entry into call_class_initializer(). 1362 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1363 ClassLoader::perf_class_init_selftime(), 1364 ClassLoader::perf_classes_inited(), 1365 jt->get_thread_stat()->perf_recursion_counts_addr(), 1366 jt->get_thread_stat()->perf_timers_addr(), 1367 PerfClassTraceTime::CLASS_CLINIT); 1368 call_class_initializer(THREAD); 1369 } else { 1370 // The elapsed time is so small it's not worth counting. 1371 if (UsePerfData) { 1372 ClassLoader::perf_classes_inited()->inc(); 1373 } 1374 call_class_initializer(THREAD); 1375 } 1376 } 1377 1378 // Step 9 1379 if (!HAS_PENDING_EXCEPTION) { 1380 set_initialization_state_and_notify(fully_initialized, CHECK); 1381 DEBUG_ONLY(vtable().verify(tty, true);) 1382 CompilationPolicy::replay_training_at_init(this, THREAD); 1383 } 1384 else { 1385 // Step 10 and 11 1386 Handle e(THREAD, PENDING_EXCEPTION); 1387 CLEAR_PENDING_EXCEPTION; 1388 // JVMTI has already reported the pending exception 1389 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1390 JvmtiExport::clear_detected_exception(jt); 1391 { 1392 EXCEPTION_MARK; 1393 add_initialization_error(THREAD, e); 1394 set_initialization_state_and_notify(initialization_error, THREAD); 1395 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1396 // JVMTI has already reported the pending exception 1397 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1398 JvmtiExport::clear_detected_exception(jt); 1399 } 1400 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1401 if (e->is_a(vmClasses::Error_klass())) { 1402 THROW_OOP(e()); 1403 } else { 1404 JavaCallArguments args(e); 1405 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1406 vmSymbols::throwable_void_signature(), 1407 &args); 1408 } 1409 } 1410 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1411 } 1412 1413 1414 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1415 Handle h_init_lock(THREAD, init_lock()); 1416 if (h_init_lock() != nullptr) { 1417 ObjectLocker ol(h_init_lock, THREAD); 1418 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1419 set_init_state(state); 1420 fence_and_clear_init_lock(); 1421 ol.notify_all(CHECK); 1422 } else { 1423 assert(h_init_lock() != nullptr, "The initialization state should never be set twice"); 1424 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1425 set_init_state(state); 1426 } 1427 } 1428 1429 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock 1430 // is grabbed, to ensure that the compiler is not using the class hierarchy. 1431 void InstanceKlass::add_to_hierarchy(JavaThread* current) { 1432 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint"); 1433 1434 DeoptimizationScope deopt_scope; 1435 { 1436 MutexLocker ml(current, Compile_lock); 1437 1438 set_init_state(InstanceKlass::loaded); 1439 // make sure init_state store is already done. 1440 // The compiler reads the hierarchy outside of the Compile_lock. 1441 // Access ordering is used to add to hierarchy. 1442 1443 // Link into hierarchy. 1444 append_to_sibling_list(); // add to superklass/sibling list 1445 process_interfaces(); // handle all "implements" declarations 1446 1447 // Now mark all code that depended on old class hierarchy. 1448 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) 1449 if (Universe::is_fully_initialized()) { 1450 CodeCache::mark_dependents_on(&deopt_scope, this); 1451 } 1452 } 1453 // Perform the deopt handshake outside Compile_lock. 1454 deopt_scope.deoptimize_marked(); 1455 } 1456 1457 1458 InstanceKlass* InstanceKlass::implementor() const { 1459 InstanceKlass* volatile* ik = adr_implementor(); 1460 if (ik == nullptr) { 1461 return nullptr; 1462 } else { 1463 // This load races with inserts, and therefore needs acquire. 1464 InstanceKlass* ikls = AtomicAccess::load_acquire(ik); 1465 if (ikls != nullptr && !ikls->is_loader_alive()) { 1466 return nullptr; // don't return unloaded class 1467 } else { 1468 return ikls; 1469 } 1470 } 1471 } 1472 1473 1474 void InstanceKlass::set_implementor(InstanceKlass* ik) { 1475 assert_locked_or_safepoint(Compile_lock); 1476 assert(is_interface(), "not interface"); 1477 InstanceKlass* volatile* addr = adr_implementor(); 1478 assert(addr != nullptr, "null addr"); 1479 if (addr != nullptr) { 1480 AtomicAccess::release_store(addr, ik); 1481 } 1482 } 1483 1484 int InstanceKlass::nof_implementors() const { 1485 InstanceKlass* ik = implementor(); 1486 if (ik == nullptr) { 1487 return 0; 1488 } else if (ik != this) { 1489 return 1; 1490 } else { 1491 return 2; 1492 } 1493 } 1494 1495 // The embedded _implementor field can only record one implementor. 1496 // When there are more than one implementors, the _implementor field 1497 // is set to the interface Klass* itself. Following are the possible 1498 // values for the _implementor field: 1499 // null - no implementor 1500 // implementor Klass* - one implementor 1501 // self - more than one implementor 1502 // 1503 // The _implementor field only exists for interfaces. 1504 void InstanceKlass::add_implementor(InstanceKlass* ik) { 1505 if (Universe::is_fully_initialized()) { 1506 assert_lock_strong(Compile_lock); 1507 } 1508 assert(is_interface(), "not interface"); 1509 // Filter out my subinterfaces. 1510 // (Note: Interfaces are never on the subklass list.) 1511 if (ik->is_interface()) return; 1512 1513 // Filter out subclasses whose supers already implement me. 1514 // (Note: CHA must walk subclasses of direct implementors 1515 // in order to locate indirect implementors.) 1516 InstanceKlass* super_ik = ik->super(); 1517 if (super_ik != nullptr && super_ik->implements_interface(this)) 1518 // We only need to check one immediate superclass, since the 1519 // implements_interface query looks at transitive_interfaces. 1520 // Any supers of the super have the same (or fewer) transitive_interfaces. 1521 return; 1522 1523 InstanceKlass* iklass = implementor(); 1524 if (iklass == nullptr) { 1525 set_implementor(ik); 1526 } else if (iklass != this && iklass != ik) { 1527 // There is already an implementor. Use itself as an indicator of 1528 // more than one implementors. 1529 set_implementor(this); 1530 } 1531 1532 // The implementor also implements the transitive_interfaces 1533 for (int index = 0; index < local_interfaces()->length(); index++) { 1534 local_interfaces()->at(index)->add_implementor(ik); 1535 } 1536 } 1537 1538 void InstanceKlass::init_implementor() { 1539 if (is_interface()) { 1540 set_implementor(nullptr); 1541 } 1542 } 1543 1544 1545 void InstanceKlass::process_interfaces() { 1546 // link this class into the implementors list of every interface it implements 1547 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1548 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1549 InstanceKlass* interf = local_interfaces()->at(i); 1550 assert(interf->is_interface(), "expected interface"); 1551 interf->add_implementor(this); 1552 } 1553 } 1554 1555 bool InstanceKlass::can_be_primary_super_slow() const { 1556 if (is_interface()) 1557 return false; 1558 else 1559 return Klass::can_be_primary_super_slow(); 1560 } 1561 1562 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1563 Array<InstanceKlass*>* transitive_interfaces) { 1564 // The secondaries are the implemented interfaces. 1565 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1566 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1567 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces; 1568 int num_secondaries = num_extra_slots + interfaces->length(); 1569 if (num_secondaries == 0) { 1570 // Must share this for correct bootstrapping! 1571 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap()); 1572 return nullptr; 1573 } else if (num_extra_slots == 0 && interfaces->length() <= 1) { 1574 // We will reuse the transitive interfaces list if we're certain 1575 // it's in hash order. 1576 uintx bitmap = compute_secondary_supers_bitmap(interfaces); 1577 set_secondary_supers(interfaces, bitmap); 1578 return nullptr; 1579 } 1580 // Copy transitive interfaces to a temporary growable array to be constructed 1581 // into the secondary super list with extra slots. 1582 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1583 for (int i = 0; i < interfaces->length(); i++) { 1584 secondaries->push(interfaces->at(i)); 1585 } 1586 return secondaries; 1587 } 1588 1589 bool InstanceKlass::implements_interface(Klass* k) const { 1590 if (this == k) return true; 1591 assert(k->is_interface(), "should be an interface class"); 1592 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1593 if (transitive_interfaces()->at(i) == k) { 1594 return true; 1595 } 1596 } 1597 return false; 1598 } 1599 1600 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1601 // Verify direct super interface 1602 if (this == k) return true; 1603 assert(k->is_interface(), "should be an interface class"); 1604 for (int i = 0; i < local_interfaces()->length(); i++) { 1605 if (local_interfaces()->at(i) == k) { 1606 return true; 1607 } 1608 } 1609 return false; 1610 } 1611 1612 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1613 if (TraceFinalizerRegistration) { 1614 tty->print("Registered "); 1615 i->print_value_on(tty); 1616 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i)); 1617 } 1618 instanceHandle h_i(THREAD, i); 1619 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1620 JavaValue result(T_VOID); 1621 JavaCallArguments args(h_i); 1622 methodHandle mh(THREAD, Universe::finalizer_register_method()); 1623 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1624 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);) 1625 return h_i(); 1626 } 1627 1628 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1629 assert(!is_abstract() && !is_interface(), "Should not create this object"); 1630 size_t size = size_helper(); // Query before forming handle. 1631 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1632 } 1633 1634 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) { 1635 Klass* k = java_lang_Class::as_Klass(java_class); 1636 if (k == nullptr) { 1637 ResourceMark rm(THREAD); 1638 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr); 1639 } 1640 InstanceKlass* ik = cast(k); 1641 ik->check_valid_for_instantiation(false, CHECK_NULL); 1642 ik->initialize(CHECK_NULL); 1643 return ik->allocate_instance(THREAD); 1644 } 1645 1646 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1647 return instanceHandle(THREAD, allocate_instance(THREAD)); 1648 } 1649 1650 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1651 if (is_interface() || is_abstract()) { 1652 ResourceMark rm(THREAD); 1653 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1654 : vmSymbols::java_lang_InstantiationException(), external_name()); 1655 } 1656 if (this == vmClasses::Class_klass()) { 1657 ResourceMark rm(THREAD); 1658 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1659 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1660 } 1661 } 1662 1663 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) { 1664 // Need load-acquire for lock-free read 1665 if (array_klasses_acquire() == nullptr) { 1666 1667 // Recursively lock array allocation 1668 RecursiveLocker rl(MultiArray_lock, THREAD); 1669 1670 // Check if another thread created the array klass while we were waiting for the lock. 1671 if (array_klasses() == nullptr) { 1672 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1673 // use 'release' to pair with lock-free load 1674 release_set_array_klasses(k); 1675 } 1676 } 1677 1678 // array_klasses() will always be set at this point 1679 ObjArrayKlass* ak = array_klasses(); 1680 assert(ak != nullptr, "should be set"); 1681 return ak->array_klass(n, THREAD); 1682 } 1683 1684 ArrayKlass* InstanceKlass::array_klass_or_null(int n) { 1685 // Need load-acquire for lock-free read 1686 ObjArrayKlass* oak = array_klasses_acquire(); 1687 if (oak == nullptr) { 1688 return nullptr; 1689 } else { 1690 return oak->array_klass_or_null(n); 1691 } 1692 } 1693 1694 ArrayKlass* InstanceKlass::array_klass(TRAPS) { 1695 return array_klass(1, THREAD); 1696 } 1697 1698 ArrayKlass* InstanceKlass::array_klass_or_null() { 1699 return array_klass_or_null(1); 1700 } 1701 1702 static int call_class_initializer_counter = 0; // for debugging 1703 1704 Method* InstanceKlass::class_initializer() const { 1705 Method* clinit = find_method( 1706 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1707 if (clinit != nullptr && clinit->has_valid_initializer_flags()) { 1708 return clinit; 1709 } 1710 return nullptr; 1711 } 1712 1713 void InstanceKlass::call_class_initializer(TRAPS) { 1714 if (ReplayCompiles && 1715 (ReplaySuppressInitializers == 1 || 1716 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) { 1717 // Hide the existence of the initializer for the purpose of replaying the compile 1718 return; 1719 } 1720 1721 #if INCLUDE_CDS 1722 // This is needed to ensure the consistency of the archived heap objects. 1723 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) { 1724 AOTClassInitializer::call_runtime_setup(THREAD, this); 1725 return; 1726 } else if (has_archived_enum_objs()) { 1727 assert(in_aot_cache(), "must be"); 1728 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK); 1729 if (initialized) { 1730 return; 1731 } 1732 } 1733 #endif 1734 1735 methodHandle h_method(THREAD, class_initializer()); 1736 assert(!is_initialized(), "we cannot initialize twice"); 1737 LogTarget(Info, class, init) lt; 1738 if (lt.is_enabled()) { 1739 ResourceMark rm(THREAD); 1740 LogStream ls(lt); 1741 ls.print("%d Initializing ", call_class_initializer_counter++); 1742 name()->print_value_on(&ls); 1743 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"", 1744 h_method() == nullptr ? "(no method)" : "", p2i(this), 1745 THREAD->name()); 1746 } 1747 if (h_method() != nullptr) { 1748 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized 1749 JavaCallArguments args; // No arguments 1750 JavaValue result(T_VOID); 1751 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1752 } 1753 } 1754 1755 // If a class that implements this interface is initialized, is the JVM required 1756 // to first execute a <clinit> method declared in this interface, 1757 // or (if also_check_supers==true) any of the super types of this interface? 1758 // 1759 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than 1760 // an interface, then let SC be its superclass and let SI1, ..., SIn 1761 // be all superinterfaces of C (whether direct or indirect) that 1762 // declare at least one non-abstract, non-static method. 1763 // 1764 // So when an interface is initialized, it does not look at its 1765 // supers. But a proper class will ensure that all of its supers have 1766 // run their <clinit> methods, except that it disregards interfaces 1767 // that lack a non-static concrete method (i.e., a default method). 1768 // Therefore, you should probably call this method only when the 1769 // current class is a super of some proper class, not an interface. 1770 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const { 1771 assert(is_interface(), "must be"); 1772 1773 if (!has_nonstatic_concrete_methods()) { 1774 // quick check: no nonstatic concrete methods are declared by this or any super interfaces 1775 return false; 1776 } 1777 1778 // JVMS 5.5. Initialization 1779 // ...If C is an interface that declares a non-abstract, 1780 // non-static method, the initialization of a class that 1781 // implements C directly or indirectly. 1782 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) { 1783 return true; 1784 } 1785 if (also_check_supers) { 1786 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 1787 for (int i = 0; i < all_ifs->length(); ++i) { 1788 InstanceKlass* super_intf = all_ifs->at(i); 1789 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) { 1790 return true; 1791 } 1792 } 1793 } 1794 return false; 1795 } 1796 1797 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1798 InterpreterOopMap* entry_for) { 1799 // Lazily create the _oop_map_cache at first request. 1800 // Load_acquire is needed to safely get instance published with CAS by another thread. 1801 OopMapCache* oop_map_cache = AtomicAccess::load_acquire(&_oop_map_cache); 1802 if (oop_map_cache == nullptr) { 1803 // Try to install new instance atomically. 1804 oop_map_cache = new OopMapCache(); 1805 OopMapCache* other = AtomicAccess::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache); 1806 if (other != nullptr) { 1807 // Someone else managed to install before us, ditch local copy and use the existing one. 1808 delete oop_map_cache; 1809 oop_map_cache = other; 1810 } 1811 } 1812 // _oop_map_cache is constant after init; lookup below does its own locking. 1813 oop_map_cache->lookup(method, bci, entry_for); 1814 } 1815 1816 bool InstanceKlass::contains_field_offset(int offset) { 1817 fieldDescriptor fd; 1818 return find_field_from_offset(offset, false, &fd); 1819 } 1820 1821 FieldInfo InstanceKlass::field(int index) const { 1822 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1823 if (fs.index() == index) { 1824 return fs.to_FieldInfo(); 1825 } 1826 } 1827 fatal("Field not found"); 1828 return FieldInfo(); 1829 } 1830 1831 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1832 JavaFieldStream fs(this); 1833 if (fs.lookup(name, sig)) { 1834 assert(fs.name() == name, "name must match"); 1835 assert(fs.signature() == sig, "signature must match"); 1836 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1837 return true; 1838 } 1839 return false; 1840 } 1841 1842 1843 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1844 const int n = local_interfaces()->length(); 1845 for (int i = 0; i < n; i++) { 1846 InstanceKlass* intf1 = local_interfaces()->at(i); 1847 assert(intf1->is_interface(), "just checking type"); 1848 // search for field in current interface 1849 if (intf1->find_local_field(name, sig, fd)) { 1850 assert(fd->is_static(), "interface field must be static"); 1851 return intf1; 1852 } 1853 // search for field in direct superinterfaces 1854 Klass* intf2 = intf1->find_interface_field(name, sig, fd); 1855 if (intf2 != nullptr) return intf2; 1856 } 1857 // otherwise field lookup fails 1858 return nullptr; 1859 } 1860 1861 1862 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1863 // search order according to newest JVM spec (5.4.3.2, p.167). 1864 // 1) search for field in current klass 1865 if (find_local_field(name, sig, fd)) { 1866 return const_cast<InstanceKlass*>(this); 1867 } 1868 // 2) search for field recursively in direct superinterfaces 1869 { Klass* intf = find_interface_field(name, sig, fd); 1870 if (intf != nullptr) return intf; 1871 } 1872 // 3) apply field lookup recursively if superclass exists 1873 { InstanceKlass* supr = super(); 1874 if (supr != nullptr) return supr->find_field(name, sig, fd); 1875 } 1876 // 4) otherwise field lookup fails 1877 return nullptr; 1878 } 1879 1880 1881 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1882 // search order according to newest JVM spec (5.4.3.2, p.167). 1883 // 1) search for field in current klass 1884 if (find_local_field(name, sig, fd)) { 1885 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1886 } 1887 // 2) search for field recursively in direct superinterfaces 1888 if (is_static) { 1889 Klass* intf = find_interface_field(name, sig, fd); 1890 if (intf != nullptr) return intf; 1891 } 1892 // 3) apply field lookup recursively if superclass exists 1893 { InstanceKlass* supr = super(); 1894 if (supr != nullptr) return supr->find_field(name, sig, is_static, fd); 1895 } 1896 // 4) otherwise field lookup fails 1897 return nullptr; 1898 } 1899 1900 1901 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1902 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1903 if (fs.offset() == offset) { 1904 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1905 if (fd->is_static() == is_static) return true; 1906 } 1907 } 1908 return false; 1909 } 1910 1911 1912 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1913 const InstanceKlass* klass = this; 1914 while (klass != nullptr) { 1915 if (klass->find_local_field_from_offset(offset, is_static, fd)) { 1916 return true; 1917 } 1918 klass = klass->super(); 1919 } 1920 return false; 1921 } 1922 1923 1924 void InstanceKlass::methods_do(void f(Method* method)) { 1925 // Methods aren't stable until they are loaded. This can be read outside 1926 // a lock through the ClassLoaderData for profiling 1927 // Redefined scratch classes are on the list and need to be cleaned 1928 if (!is_loaded() && !is_scratch_class()) { 1929 return; 1930 } 1931 1932 int len = methods()->length(); 1933 for (int index = 0; index < len; index++) { 1934 Method* m = methods()->at(index); 1935 assert(m->is_method(), "must be method"); 1936 f(m); 1937 } 1938 } 1939 1940 1941 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1942 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1943 if (fs.access_flags().is_static()) { 1944 fieldDescriptor& fd = fs.field_descriptor(); 1945 cl->do_field(&fd); 1946 } 1947 } 1948 } 1949 1950 1951 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1952 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1953 if (fs.access_flags().is_static()) { 1954 fieldDescriptor& fd = fs.field_descriptor(); 1955 f(&fd, mirror, CHECK); 1956 } 1957 } 1958 } 1959 1960 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1961 InstanceKlass* super = this->super(); 1962 if (super != nullptr) { 1963 super->do_nonstatic_fields(cl); 1964 } 1965 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1966 fieldDescriptor& fd = fs.field_descriptor(); 1967 if (!fd.is_static()) { 1968 cl->do_field(&fd); 1969 } 1970 } 1971 } 1972 1973 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) { 1974 return a->offset() - b->offset(); 1975 } 1976 1977 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) { 1978 InstanceKlass* super = this->super(); 1979 if (super != nullptr) { 1980 super->print_nonstatic_fields(cl); 1981 } 1982 ResourceMark rm; 1983 // In DebugInfo nonstatic fields are sorted by offset. 1984 GrowableArray<FieldInfo> fields_sorted; 1985 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1986 if (!fs.access_flags().is_static()) { 1987 fields_sorted.push(fs.to_FieldInfo()); 1988 } 1989 } 1990 int length = fields_sorted.length(); 1991 if (length > 0) { 1992 fields_sorted.sort(compare_fields_by_offset); 1993 fieldDescriptor fd; 1994 for (int i = 0; i < length; i++) { 1995 fd.reinitialize(this, fields_sorted.at(i)); 1996 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields"); 1997 cl->do_field(&fd); 1998 } 1999 } 2000 } 2001 2002 #ifdef ASSERT 2003 static int linear_search(const Array<Method*>* methods, 2004 const Symbol* name, 2005 const Symbol* signature) { 2006 const int len = methods->length(); 2007 for (int index = 0; index < len; index++) { 2008 const Method* const m = methods->at(index); 2009 assert(m->is_method(), "must be method"); 2010 if (m->signature() == signature && m->name() == name) { 2011 return index; 2012 } 2013 } 2014 return -1; 2015 } 2016 #endif 2017 2018 bool InstanceKlass::_disable_method_binary_search = false; 2019 2020 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 2021 int len = methods->length(); 2022 int l = 0; 2023 int h = len - 1; 2024 while (l <= h) { 2025 Method* m = methods->at(l); 2026 if (m->name() == name) { 2027 return l; 2028 } 2029 l++; 2030 } 2031 return -1; 2032 } 2033 2034 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 2035 if (_disable_method_binary_search) { 2036 assert(CDSConfig::is_dumping_dynamic_archive(), "must be"); 2037 // At the final stage of dynamic dumping, the methods array may not be sorted 2038 // by ascending addresses of their names, so we can't use binary search anymore. 2039 // However, methods with the same name are still laid out consecutively inside the 2040 // methods array, so let's look for the first one that matches. 2041 return linear_search(methods, name); 2042 } 2043 2044 int len = methods->length(); 2045 int l = 0; 2046 int h = len - 1; 2047 2048 // methods are sorted by ascending addresses of their names, so do binary search 2049 while (l <= h) { 2050 int mid = (l + h) >> 1; 2051 Method* m = methods->at(mid); 2052 assert(m->is_method(), "must be method"); 2053 int res = m->name()->fast_compare(name); 2054 if (res == 0) { 2055 return mid; 2056 } else if (res < 0) { 2057 l = mid + 1; 2058 } else { 2059 h = mid - 1; 2060 } 2061 } 2062 return -1; 2063 } 2064 2065 // find_method looks up the name/signature in the local methods array 2066 Method* InstanceKlass::find_method(const Symbol* name, 2067 const Symbol* signature) const { 2068 return find_method_impl(name, signature, 2069 OverpassLookupMode::find, 2070 StaticLookupMode::find, 2071 PrivateLookupMode::find); 2072 } 2073 2074 Method* InstanceKlass::find_method_impl(const Symbol* name, 2075 const Symbol* signature, 2076 OverpassLookupMode overpass_mode, 2077 StaticLookupMode static_mode, 2078 PrivateLookupMode private_mode) const { 2079 return InstanceKlass::find_method_impl(methods(), 2080 name, 2081 signature, 2082 overpass_mode, 2083 static_mode, 2084 private_mode); 2085 } 2086 2087 // find_instance_method looks up the name/signature in the local methods array 2088 // and skips over static methods 2089 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 2090 const Symbol* name, 2091 const Symbol* signature, 2092 PrivateLookupMode private_mode) { 2093 Method* const meth = InstanceKlass::find_method_impl(methods, 2094 name, 2095 signature, 2096 OverpassLookupMode::find, 2097 StaticLookupMode::skip, 2098 private_mode); 2099 assert(((meth == nullptr) || !meth->is_static()), 2100 "find_instance_method should have skipped statics"); 2101 return meth; 2102 } 2103 2104 // find_instance_method looks up the name/signature in the local methods array 2105 // and skips over static methods 2106 Method* InstanceKlass::find_instance_method(const Symbol* name, 2107 const Symbol* signature, 2108 PrivateLookupMode private_mode) const { 2109 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 2110 } 2111 2112 // Find looks up the name/signature in the local methods array 2113 // and filters on the overpass, static and private flags 2114 // This returns the first one found 2115 // note that the local methods array can have up to one overpass, one static 2116 // and one instance (private or not) with the same name/signature 2117 Method* InstanceKlass::find_local_method(const Symbol* name, 2118 const Symbol* signature, 2119 OverpassLookupMode overpass_mode, 2120 StaticLookupMode static_mode, 2121 PrivateLookupMode private_mode) const { 2122 return InstanceKlass::find_method_impl(methods(), 2123 name, 2124 signature, 2125 overpass_mode, 2126 static_mode, 2127 private_mode); 2128 } 2129 2130 // Find looks up the name/signature in the local methods array 2131 // and filters on the overpass, static and private flags 2132 // This returns the first one found 2133 // note that the local methods array can have up to one overpass, one static 2134 // and one instance (private or not) with the same name/signature 2135 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 2136 const Symbol* name, 2137 const Symbol* signature, 2138 OverpassLookupMode overpass_mode, 2139 StaticLookupMode static_mode, 2140 PrivateLookupMode private_mode) { 2141 return InstanceKlass::find_method_impl(methods, 2142 name, 2143 signature, 2144 overpass_mode, 2145 static_mode, 2146 private_mode); 2147 } 2148 2149 Method* InstanceKlass::find_method(const Array<Method*>* methods, 2150 const Symbol* name, 2151 const Symbol* signature) { 2152 return InstanceKlass::find_method_impl(methods, 2153 name, 2154 signature, 2155 OverpassLookupMode::find, 2156 StaticLookupMode::find, 2157 PrivateLookupMode::find); 2158 } 2159 2160 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 2161 const Symbol* name, 2162 const Symbol* signature, 2163 OverpassLookupMode overpass_mode, 2164 StaticLookupMode static_mode, 2165 PrivateLookupMode private_mode) { 2166 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 2167 return hit >= 0 ? methods->at(hit): nullptr; 2168 } 2169 2170 // true if method matches signature and conforms to skipping_X conditions. 2171 static bool method_matches(const Method* m, 2172 const Symbol* signature, 2173 bool skipping_overpass, 2174 bool skipping_static, 2175 bool skipping_private) { 2176 return ((m->signature() == signature) && 2177 (!skipping_overpass || !m->is_overpass()) && 2178 (!skipping_static || !m->is_static()) && 2179 (!skipping_private || !m->is_private())); 2180 } 2181 2182 // Used directly for default_methods to find the index into the 2183 // default_vtable_indices, and indirectly by find_method 2184 // find_method_index looks in the local methods array to return the index 2185 // of the matching name/signature. If, overpass methods are being ignored, 2186 // the search continues to find a potential non-overpass match. This capability 2187 // is important during method resolution to prefer a static method, for example, 2188 // over an overpass method. 2189 // There is the possibility in any _method's array to have the same name/signature 2190 // for a static method, an overpass method and a local instance method 2191 // To correctly catch a given method, the search criteria may need 2192 // to explicitly skip the other two. For local instance methods, it 2193 // is often necessary to skip private methods 2194 int InstanceKlass::find_method_index(const Array<Method*>* methods, 2195 const Symbol* name, 2196 const Symbol* signature, 2197 OverpassLookupMode overpass_mode, 2198 StaticLookupMode static_mode, 2199 PrivateLookupMode private_mode) { 2200 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip); 2201 const bool skipping_static = (static_mode == StaticLookupMode::skip); 2202 const bool skipping_private = (private_mode == PrivateLookupMode::skip); 2203 const int hit = quick_search(methods, name); 2204 if (hit != -1) { 2205 const Method* const m = methods->at(hit); 2206 2207 // Do linear search to find matching signature. First, quick check 2208 // for common case, ignoring overpasses if requested. 2209 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2210 return hit; 2211 } 2212 2213 // search downwards through overloaded methods 2214 int i; 2215 for (i = hit - 1; i >= 0; --i) { 2216 const Method* const m = methods->at(i); 2217 assert(m->is_method(), "must be method"); 2218 if (m->name() != name) { 2219 break; 2220 } 2221 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2222 return i; 2223 } 2224 } 2225 // search upwards 2226 for (i = hit + 1; i < methods->length(); ++i) { 2227 const Method* const m = methods->at(i); 2228 assert(m->is_method(), "must be method"); 2229 if (m->name() != name) { 2230 break; 2231 } 2232 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2233 return i; 2234 } 2235 } 2236 // not found 2237 #ifdef ASSERT 2238 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 2239 linear_search(methods, name, signature); 2240 assert(-1 == index, "binary search should have found entry %d", index); 2241 #endif 2242 } 2243 return -1; 2244 } 2245 2246 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 2247 return find_method_by_name(methods(), name, end); 2248 } 2249 2250 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 2251 const Symbol* name, 2252 int* end_ptr) { 2253 assert(end_ptr != nullptr, "just checking"); 2254 int start = quick_search(methods, name); 2255 int end = start + 1; 2256 if (start != -1) { 2257 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 2258 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 2259 *end_ptr = end; 2260 return start; 2261 } 2262 return -1; 2263 } 2264 2265 // uncached_lookup_method searches both the local class methods array and all 2266 // superclasses methods arrays, skipping any overpass methods in superclasses, 2267 // and possibly skipping private methods. 2268 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 2269 const Symbol* signature, 2270 OverpassLookupMode overpass_mode, 2271 PrivateLookupMode private_mode) const { 2272 OverpassLookupMode overpass_local_mode = overpass_mode; 2273 const InstanceKlass* klass = this; 2274 while (klass != nullptr) { 2275 Method* const method = klass->find_method_impl(name, 2276 signature, 2277 overpass_local_mode, 2278 StaticLookupMode::find, 2279 private_mode); 2280 if (method != nullptr) { 2281 return method; 2282 } 2283 klass = klass->super(); 2284 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses 2285 } 2286 return nullptr; 2287 } 2288 2289 #ifdef ASSERT 2290 // search through class hierarchy and return true if this class or 2291 // one of the superclasses was redefined 2292 bool InstanceKlass::has_redefined_this_or_super() const { 2293 const InstanceKlass* klass = this; 2294 while (klass != nullptr) { 2295 if (klass->has_been_redefined()) { 2296 return true; 2297 } 2298 klass = klass->super(); 2299 } 2300 return false; 2301 } 2302 #endif 2303 2304 // lookup a method in the default methods list then in all transitive interfaces 2305 // Do NOT return private or static methods 2306 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 2307 Symbol* signature) const { 2308 Method* m = nullptr; 2309 if (default_methods() != nullptr) { 2310 m = find_method(default_methods(), name, signature); 2311 } 2312 // Look up interfaces 2313 if (m == nullptr) { 2314 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find); 2315 } 2316 return m; 2317 } 2318 2319 // lookup a method in all the interfaces that this class implements 2320 // Do NOT return private or static methods, new in JDK8 which are not externally visible 2321 // They should only be found in the initial InterfaceMethodRef 2322 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 2323 Symbol* signature, 2324 DefaultsLookupMode defaults_mode) const { 2325 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 2326 int num_ifs = all_ifs->length(); 2327 InstanceKlass *ik = nullptr; 2328 for (int i = 0; i < num_ifs; i++) { 2329 ik = all_ifs->at(i); 2330 Method* m = ik->lookup_method(name, signature); 2331 if (m != nullptr && m->is_public() && !m->is_static() && 2332 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) { 2333 return m; 2334 } 2335 } 2336 return nullptr; 2337 } 2338 2339 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose) 2340 :_st(st), _verbose(verbose) { 2341 ResourceMark rm; 2342 _st->print("%-18s ", "KlassAddr"); 2343 _st->print("%-4s ", "Size"); 2344 _st->print("%-20s ", "State"); 2345 _st->print("%-7s ", "Flags"); 2346 _st->print("%-5s ", "ClassName"); 2347 _st->cr(); 2348 } 2349 2350 void PrintClassClosure::do_klass(Klass* k) { 2351 ResourceMark rm; 2352 // klass pointer 2353 _st->print(PTR_FORMAT " ", p2i(k)); 2354 // klass size 2355 _st->print("%4d ", k->size()); 2356 // initialization state 2357 if (k->is_instance_klass()) { 2358 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name()); 2359 } else { 2360 _st->print("%-20s ",""); 2361 } 2362 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc) 2363 char buf[10]; 2364 int i = 0; 2365 if (k->has_finalizer()) buf[i++] = 'F'; 2366 if (k->is_instance_klass()) { 2367 InstanceKlass* ik = InstanceKlass::cast(k); 2368 if (ik->has_final_method()) buf[i++] = 'f'; 2369 if (ik->is_rewritten()) buf[i++] = 'W'; 2370 if (ik->is_contended()) buf[i++] = 'C'; 2371 if (ik->has_been_redefined()) buf[i++] = 'R'; 2372 if (ik->in_aot_cache()) buf[i++] = 'S'; 2373 } 2374 buf[i++] = '\0'; 2375 _st->print("%-7s ", buf); 2376 // klass name 2377 _st->print("%-5s ", k->external_name()); 2378 // end 2379 _st->cr(); 2380 if (_verbose) { 2381 k->print_on(_st); 2382 } 2383 } 2384 2385 /* jni_id_for for jfieldIds only */ 2386 JNIid* InstanceKlass::jni_id_for(int offset) { 2387 MutexLocker ml(JfieldIdCreation_lock); 2388 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset); 2389 if (probe == nullptr) { 2390 // Allocate new static field identifier 2391 probe = new JNIid(this, offset, jni_ids()); 2392 set_jni_ids(probe); 2393 } 2394 return probe; 2395 } 2396 2397 u2 InstanceKlass::enclosing_method_data(int offset) const { 2398 const Array<jushort>* const inner_class_list = inner_classes(); 2399 if (inner_class_list == nullptr) { 2400 return 0; 2401 } 2402 const int length = inner_class_list->length(); 2403 if (length % inner_class_next_offset == 0) { 2404 return 0; 2405 } 2406 const int index = length - enclosing_method_attribute_size; 2407 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2408 return inner_class_list->at(index + offset); 2409 } 2410 2411 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2412 u2 method_index) { 2413 Array<jushort>* inner_class_list = inner_classes(); 2414 assert (inner_class_list != nullptr, "_inner_classes list is not set up"); 2415 int length = inner_class_list->length(); 2416 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2417 int index = length - enclosing_method_attribute_size; 2418 inner_class_list->at_put( 2419 index + enclosing_method_class_index_offset, class_index); 2420 inner_class_list->at_put( 2421 index + enclosing_method_method_index_offset, method_index); 2422 } 2423 } 2424 2425 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) { 2426 if (method->is_old() && !method->is_obsolete()) { 2427 // If the method passed in is old (but not obsolete), use the current version. 2428 method = method_with_idnum((int)idnum); 2429 assert(method != nullptr, "old and but not obsolete, so should exist"); 2430 } 2431 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method); 2432 AtomicAccess::release_store(&jmeths[idnum + 1], new_id); 2433 return new_id; 2434 } 2435 2436 // Allocate the jmethodID cache. 2437 static jmethodID* create_jmethod_id_cache(size_t size) { 2438 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2439 memset(jmeths, 0, (size + 1) * sizeof(jmethodID)); 2440 // cache size is stored in element[0], other elements offset by one 2441 jmeths[0] = (jmethodID)size; 2442 return jmeths; 2443 } 2444 2445 // When reading outside a lock, use this. 2446 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const { 2447 return AtomicAccess::load_acquire(&_methods_jmethod_ids); 2448 } 2449 2450 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) { 2451 AtomicAccess::release_store(&_methods_jmethod_ids, jmeths); 2452 } 2453 2454 // Lookup or create a jmethodID. 2455 jmethodID InstanceKlass::get_jmethod_id(Method* method) { 2456 int idnum = method->method_idnum(); 2457 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2458 2459 // We use a double-check locking idiom here because this cache is 2460 // performance sensitive. In the normal system, this cache only 2461 // transitions from null to non-null which is safe because we use 2462 // release_set_methods_jmethod_ids() to advertise the new cache. 2463 // A partially constructed cache should never be seen by a racing 2464 // thread. We also use release_store() to save a new jmethodID 2465 // in the cache so a partially constructed jmethodID should never be 2466 // seen either. Cache reads of existing jmethodIDs proceed without a 2467 // lock, but cache writes of a new jmethodID requires uniqueness and 2468 // creation of the cache itself requires no leaks so a lock is 2469 // acquired in those two cases. 2470 // 2471 // If the RedefineClasses() API has been used, then this cache grows 2472 // in the redefinition safepoint. 2473 2474 if (jmeths == nullptr) { 2475 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2476 jmeths = _methods_jmethod_ids; 2477 // Still null? 2478 if (jmeths == nullptr) { 2479 size_t size = idnum_allocated_count(); 2480 assert(size > (size_t)idnum, "should already have space"); 2481 jmeths = create_jmethod_id_cache(size); 2482 jmethodID new_id = update_jmethod_id(jmeths, method, idnum); 2483 2484 // publish jmeths 2485 release_set_methods_jmethod_ids(jmeths); 2486 return new_id; 2487 } 2488 } 2489 2490 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]); 2491 if (id == nullptr) { 2492 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2493 id = jmeths[idnum + 1]; 2494 // Still null? 2495 if (id == nullptr) { 2496 return update_jmethod_id(jmeths, method, idnum); 2497 } 2498 } 2499 return id; 2500 } 2501 2502 void InstanceKlass::update_methods_jmethod_cache() { 2503 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2504 jmethodID* cache = _methods_jmethod_ids; 2505 if (cache != nullptr) { 2506 size_t size = idnum_allocated_count(); 2507 size_t old_size = (size_t)cache[0]; 2508 if (old_size < size + 1) { 2509 // Allocate a larger one and copy entries to the new one. 2510 // They've already been updated to point to new methods where applicable (i.e., not obsolete). 2511 jmethodID* new_cache = create_jmethod_id_cache(size); 2512 2513 for (int i = 1; i <= (int)old_size; i++) { 2514 new_cache[i] = cache[i]; 2515 } 2516 _methods_jmethod_ids = new_cache; 2517 FREE_C_HEAP_ARRAY(jmethodID, cache); 2518 } 2519 } 2520 } 2521 2522 // Make a jmethodID for all methods in this class. This makes getting all method 2523 // ids much, much faster with classes with more than 8 2524 // methods, and has a *substantial* effect on performance with jvmti 2525 // code that loads all jmethodIDs for all classes. 2526 void InstanceKlass::make_methods_jmethod_ids() { 2527 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2528 jmethodID* jmeths = _methods_jmethod_ids; 2529 if (jmeths == nullptr) { 2530 jmeths = create_jmethod_id_cache(idnum_allocated_count()); 2531 release_set_methods_jmethod_ids(jmeths); 2532 } 2533 2534 int length = methods()->length(); 2535 for (int index = 0; index < length; index++) { 2536 Method* m = methods()->at(index); 2537 int idnum = m->method_idnum(); 2538 assert(!m->is_old(), "should not have old methods or I'm confused"); 2539 jmethodID id = AtomicAccess::load_acquire(&jmeths[idnum + 1]); 2540 if (!m->is_overpass() && // skip overpasses 2541 id == nullptr) { 2542 id = Method::make_jmethod_id(class_loader_data(), m); 2543 AtomicAccess::release_store(&jmeths[idnum + 1], id); 2544 } 2545 } 2546 } 2547 2548 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles 2549 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2550 int idnum = method->method_idnum(); 2551 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2552 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr; 2553 } 2554 2555 inline DependencyContext InstanceKlass::dependencies() { 2556 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2557 return dep_context; 2558 } 2559 2560 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) { 2561 dependencies().mark_dependent_nmethods(deopt_scope, changes); 2562 } 2563 2564 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2565 assert_lock_strong(CodeCache_lock); 2566 dependencies().add_dependent_nmethod(nm); 2567 } 2568 2569 void InstanceKlass::clean_dependency_context() { 2570 dependencies().clean_unloading_dependents(); 2571 } 2572 2573 #ifndef PRODUCT 2574 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2575 dependencies().print_dependent_nmethods(verbose); 2576 } 2577 2578 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2579 return dependencies().is_dependent_nmethod(nm); 2580 } 2581 #endif //PRODUCT 2582 2583 void InstanceKlass::clean_weak_instanceklass_links() { 2584 clean_implementors_list(); 2585 clean_method_data(); 2586 } 2587 2588 void InstanceKlass::clean_implementors_list() { 2589 assert(is_loader_alive(), "this klass should be live"); 2590 if (is_interface()) { 2591 assert (ClassUnloading, "only called for ClassUnloading"); 2592 for (;;) { 2593 // Use load_acquire due to competing with inserts 2594 InstanceKlass* volatile* iklass = adr_implementor(); 2595 assert(iklass != nullptr, "Klass must not be null"); 2596 InstanceKlass* impl = AtomicAccess::load_acquire(iklass); 2597 if (impl != nullptr && !impl->is_loader_alive()) { 2598 // null this field, might be an unloaded instance klass or null 2599 if (AtomicAccess::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) { 2600 // Successfully unlinking implementor. 2601 if (log_is_enabled(Trace, class, unload)) { 2602 ResourceMark rm; 2603 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2604 } 2605 return; 2606 } 2607 } else { 2608 return; 2609 } 2610 } 2611 } 2612 } 2613 2614 void InstanceKlass::clean_method_data() { 2615 for (int m = 0; m < methods()->length(); m++) { 2616 MethodData* mdo = methods()->at(m)->method_data(); 2617 if (mdo != nullptr) { 2618 mdo->clean_method_data(/*always_clean*/false); 2619 } 2620 } 2621 } 2622 2623 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2624 Klass::metaspace_pointers_do(it); 2625 2626 if (log_is_enabled(Trace, aot)) { 2627 ResourceMark rm; 2628 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2629 } 2630 2631 it->push(&_annotations); 2632 it->push((Klass**)&_array_klasses); 2633 if (!is_rewritten()) { 2634 it->push(&_constants, MetaspaceClosure::_writable); 2635 } else { 2636 it->push(&_constants); 2637 } 2638 it->push(&_inner_classes); 2639 #if INCLUDE_JVMTI 2640 it->push(&_previous_versions); 2641 #endif 2642 #if INCLUDE_CDS 2643 // For "old" classes with methods containing the jsr bytecode, the _methods array will 2644 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely 2645 // checked here with ByteCodeStream. All methods that can't be verified are made writable. 2646 // The length check on the _methods is necessary because classes which don't have any 2647 // methods share the Universe::_the_empty_method_array which is in the RO region. 2648 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) { 2649 // To handle jsr bytecode, new Method* maybe stored into _methods 2650 it->push(&_methods, MetaspaceClosure::_writable); 2651 } else { 2652 #endif 2653 it->push(&_methods); 2654 #if INCLUDE_CDS 2655 } 2656 #endif 2657 it->push(&_default_methods); 2658 it->push(&_local_interfaces); 2659 it->push(&_transitive_interfaces); 2660 it->push(&_method_ordering); 2661 if (!is_rewritten()) { 2662 it->push(&_default_vtable_indices, MetaspaceClosure::_writable); 2663 } else { 2664 it->push(&_default_vtable_indices); 2665 } 2666 2667 it->push(&_fieldinfo_stream); 2668 it->push(&_fieldinfo_search_table); 2669 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update() 2670 it->push(&_fields_status, MetaspaceClosure::_writable); 2671 2672 if (itable_length() > 0) { 2673 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2674 int method_table_offset_in_words = ioe->offset()/wordSize; 2675 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this); 2676 2677 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words) 2678 / itableOffsetEntry::size(); 2679 2680 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2681 if (ioe->interface_klass() != nullptr) { 2682 it->push(ioe->interface_klass_addr()); 2683 itableMethodEntry* ime = ioe->first_method_entry(this); 2684 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2685 for (int index = 0; index < n; index ++) { 2686 it->push(ime[index].method_addr()); 2687 } 2688 } 2689 } 2690 } 2691 2692 it->push(&_nest_host); 2693 it->push(&_nest_members); 2694 it->push(&_permitted_subclasses); 2695 it->push(&_record_components); 2696 } 2697 2698 #if INCLUDE_CDS 2699 void InstanceKlass::remove_unshareable_info() { 2700 2701 if (is_linked()) { 2702 assert(can_be_verified_at_dumptime(), "must be"); 2703 // Remember this so we can avoid walking the hierarchy at runtime. 2704 set_verified_at_dump_time(); 2705 } 2706 2707 _misc_flags.set_has_init_deps_processed(false); 2708 2709 Klass::remove_unshareable_info(); 2710 2711 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2712 // Classes are attempted to link during dumping and may fail, 2713 // but these classes are still in the dictionary and class list in CLD. 2714 // If the class has failed verification, there is nothing else to remove. 2715 return; 2716 } 2717 2718 // Reset to the 'allocated' state to prevent any premature accessing to 2719 // a shared class at runtime while the class is still being loaded and 2720 // restored. A class' init_state is set to 'loaded' at runtime when it's 2721 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()). 2722 _init_state = allocated; 2723 2724 { // Otherwise this needs to take out the Compile_lock. 2725 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2726 init_implementor(); 2727 } 2728 2729 // Call remove_unshareable_info() on other objects that belong to this class, except 2730 // for constants()->remove_unshareable_info(), which is called in a separate pass in 2731 // ArchiveBuilder::make_klasses_shareable(), 2732 2733 for (int i = 0; i < methods()->length(); i++) { 2734 Method* m = methods()->at(i); 2735 m->remove_unshareable_info(); 2736 } 2737 2738 // do array classes also. 2739 if (array_klasses() != nullptr) { 2740 array_klasses()->remove_unshareable_info(); 2741 } 2742 2743 // These are not allocated from metaspace. They are safe to set to null. 2744 _source_debug_extension = nullptr; 2745 _dep_context = nullptr; 2746 _osr_nmethods_head = nullptr; 2747 #if INCLUDE_JVMTI 2748 _breakpoints = nullptr; 2749 _previous_versions = nullptr; 2750 _cached_class_file = nullptr; 2751 _jvmti_cached_class_field_map = nullptr; 2752 #endif 2753 2754 _init_thread = nullptr; 2755 _methods_jmethod_ids = nullptr; 2756 _jni_ids = nullptr; 2757 _oop_map_cache = nullptr; 2758 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) { 2759 // keep _nest_host 2760 } else { 2761 // clear _nest_host to ensure re-load at runtime 2762 _nest_host = nullptr; 2763 } 2764 init_shared_package_entry(); 2765 _dep_context_last_cleaned = 0; 2766 DEBUG_ONLY(_shared_class_load_count = 0); 2767 2768 remove_unshareable_flags(); 2769 2770 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table)); 2771 } 2772 2773 void InstanceKlass::remove_unshareable_flags() { 2774 // clear all the flags/stats that shouldn't be in the archived version 2775 assert(!is_scratch_class(), "must be"); 2776 assert(!has_been_redefined(), "must be"); 2777 #if INCLUDE_JVMTI 2778 set_is_being_redefined(false); 2779 #endif 2780 set_has_resolved_methods(false); 2781 } 2782 2783 void InstanceKlass::remove_java_mirror() { 2784 Klass::remove_java_mirror(); 2785 2786 // do array classes also. 2787 if (array_klasses() != nullptr) { 2788 array_klasses()->remove_java_mirror(); 2789 } 2790 } 2791 2792 void InstanceKlass::init_shared_package_entry() { 2793 assert(CDSConfig::is_dumping_archive(), "must be"); 2794 #if !INCLUDE_CDS_JAVA_HEAP 2795 _package_entry = nullptr; 2796 #else 2797 if (CDSConfig::is_dumping_full_module_graph()) { 2798 if (defined_by_other_loaders()) { 2799 _package_entry = nullptr; 2800 } else { 2801 _package_entry = PackageEntry::get_archived_entry(_package_entry); 2802 } 2803 } else if (CDSConfig::is_dumping_dynamic_archive() && 2804 CDSConfig::is_using_full_module_graph() && 2805 AOTMetaspace::in_aot_cache(_package_entry)) { 2806 // _package_entry is an archived package in the base archive. Leave it as is. 2807 } else { 2808 _package_entry = nullptr; 2809 } 2810 ArchivePtrMarker::mark_pointer((address**)&_package_entry); 2811 #endif 2812 } 2813 2814 void InstanceKlass::compute_has_loops_flag_for_methods() { 2815 Array<Method*>* methods = this->methods(); 2816 for (int index = 0; index < methods->length(); ++index) { 2817 Method* m = methods->at(index); 2818 if (!m->is_overpass()) { // work around JDK-8305771 2819 m->compute_has_loops_flag(); 2820 } 2821 } 2822 } 2823 2824 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2825 PackageEntry* pkg_entry, TRAPS) { 2826 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded 2827 // before the InstanceKlass is added to the SystemDictionary. Make 2828 // sure the current state is <loaded. 2829 assert(!is_loaded(), "invalid init state"); 2830 assert(!shared_loading_failed(), "Must not try to load failed class again"); 2831 set_package(loader_data, pkg_entry, CHECK); 2832 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2833 2834 Array<Method*>* methods = this->methods(); 2835 int num_methods = methods->length(); 2836 for (int index = 0; index < num_methods; ++index) { 2837 methods->at(index)->restore_unshareable_info(CHECK); 2838 } 2839 #if INCLUDE_JVMTI 2840 if (JvmtiExport::has_redefined_a_class()) { 2841 // Reinitialize vtable because RedefineClasses may have changed some 2842 // entries in this vtable for super classes so the CDS vtable might 2843 // point to old or obsolete entries. RedefineClasses doesn't fix up 2844 // vtables in the shared system dictionary, only the main one. 2845 // It also redefines the itable too so fix that too. 2846 // First fix any default methods that point to a super class that may 2847 // have been redefined. 2848 bool trace_name_printed = false; 2849 adjust_default_methods(&trace_name_printed); 2850 if (verified_at_dump_time()) { 2851 // Initialize vtable and itable for classes which can be verified at dump time. 2852 // Unlinked classes such as old classes with major version < 50 cannot be verified 2853 // at dump time. 2854 vtable().initialize_vtable(); 2855 itable().initialize_itable(); 2856 } 2857 } 2858 #endif // INCLUDE_JVMTI 2859 2860 // restore constant pool resolved references 2861 constants()->restore_unshareable_info(CHECK); 2862 2863 if (array_klasses() != nullptr) { 2864 // To get a consistent list of classes we need MultiArray_lock to ensure 2865 // array classes aren't observed while they are being restored. 2866 RecursiveLocker rl(MultiArray_lock, THREAD); 2867 assert(this == array_klasses()->bottom_klass(), "sanity"); 2868 // Array classes have null protection domain. 2869 // --> see ArrayKlass::complete_create_array_klass() 2870 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK); 2871 } 2872 2873 // Initialize @ValueBased class annotation if not already set in the archived klass. 2874 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) { 2875 set_is_value_based(); 2876 } 2877 2878 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table)); 2879 } 2880 2881 bool InstanceKlass::can_be_verified_at_dumptime() const { 2882 if (CDSConfig::is_dumping_dynamic_archive() && AOTMetaspace::in_aot_cache(this)) { 2883 // This is a class that was dumped into the base archive, so we know 2884 // it was verified at dump time. 2885 return true; 2886 } 2887 2888 if (CDSConfig::is_preserving_verification_constraints()) { 2889 return true; 2890 } 2891 2892 if (CDSConfig::is_old_class_for_verifier(this)) { 2893 // The old verifier does not save verification constraints, so at run time 2894 // SystemDictionaryShared::check_verification_constraints() will not work for this class. 2895 return false; 2896 } 2897 if (super() != nullptr && !super()->can_be_verified_at_dumptime()) { 2898 return false; 2899 } 2900 Array<InstanceKlass*>* interfaces = local_interfaces(); 2901 int len = interfaces->length(); 2902 for (int i = 0; i < len; i++) { 2903 if (!interfaces->at(i)->can_be_verified_at_dumptime()) { 2904 return false; 2905 } 2906 } 2907 return true; 2908 } 2909 2910 #endif // INCLUDE_CDS 2911 2912 #if INCLUDE_JVMTI 2913 static void clear_all_breakpoints(Method* m) { 2914 m->clear_all_breakpoints(); 2915 } 2916 #endif 2917 2918 void InstanceKlass::unload_class(InstanceKlass* ik) { 2919 2920 if (ik->is_scratch_class()) { 2921 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes"); 2922 return; 2923 } 2924 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik)); 2925 2926 // Release dependencies. 2927 ik->dependencies().remove_all_dependents(); 2928 2929 // notify the debugger 2930 if (JvmtiExport::should_post_class_unload()) { 2931 JvmtiExport::post_class_unload(ik); 2932 } 2933 2934 // notify ClassLoadingService of class unload 2935 ClassLoadingService::notify_class_unloaded(ik); 2936 2937 SystemDictionaryShared::handle_class_unloading(ik); 2938 2939 if (log_is_enabled(Info, class, unload)) { 2940 ResourceMark rm; 2941 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik)); 2942 } 2943 2944 Events::log_class_unloading(Thread::current(), ik); 2945 2946 #if INCLUDE_JFR 2947 assert(ik != nullptr, "invariant"); 2948 EventClassUnload event; 2949 event.set_unloadedClass(ik); 2950 event.set_definingClassLoader(ik->class_loader_data()); 2951 event.commit(); 2952 #endif 2953 } 2954 2955 static void method_release_C_heap_structures(Method* m) { 2956 m->release_C_heap_structures(); 2957 } 2958 2959 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata. 2960 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) { 2961 // Clean up C heap 2962 Klass::release_C_heap_structures(); 2963 2964 // Deallocate and call destructors for MDO mutexes 2965 if (release_sub_metadata) { 2966 methods_do(method_release_C_heap_structures); 2967 } 2968 2969 // Deallocate oop map cache 2970 if (_oop_map_cache != nullptr) { 2971 delete _oop_map_cache; 2972 _oop_map_cache = nullptr; 2973 } 2974 2975 // Deallocate JNI identifiers for jfieldIDs 2976 JNIid::deallocate(jni_ids()); 2977 set_jni_ids(nullptr); 2978 2979 jmethodID* jmeths = _methods_jmethod_ids; 2980 if (jmeths != nullptr) { 2981 release_set_methods_jmethod_ids(nullptr); 2982 FreeHeap(jmeths); 2983 } 2984 2985 assert(_dep_context == nullptr, 2986 "dependencies should already be cleaned"); 2987 2988 #if INCLUDE_JVMTI 2989 // Deallocate breakpoint records 2990 if (breakpoints() != nullptr) { 2991 methods_do(clear_all_breakpoints); 2992 assert(breakpoints() == nullptr, "should have cleared breakpoints"); 2993 } 2994 2995 // deallocate the cached class file 2996 if (_cached_class_file != nullptr) { 2997 os::free(_cached_class_file); 2998 _cached_class_file = nullptr; 2999 } 3000 #endif 3001 3002 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 3003 3004 if (release_sub_metadata) { 3005 constants()->release_C_heap_structures(); 3006 } 3007 } 3008 3009 // The constant pool is on stack if any of the methods are executing or 3010 // referenced by handles. 3011 bool InstanceKlass::on_stack() const { 3012 return _constants->on_stack(); 3013 } 3014 3015 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); } 3016 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); } 3017 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); } 3018 3019 // minor and major version numbers of class file 3020 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); } 3021 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); } 3022 u2 InstanceKlass::major_version() const { return _constants->major_version(); } 3023 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); } 3024 3025 const InstanceKlass* InstanceKlass::get_klass_version(int version) const { 3026 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) { 3027 if (ik->constants()->version() == version) { 3028 return ik; 3029 } 3030 } 3031 return nullptr; 3032 } 3033 3034 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 3035 if (array == nullptr) { 3036 _source_debug_extension = nullptr; 3037 } else { 3038 // Adding one to the attribute length in order to store a null terminator 3039 // character could cause an overflow because the attribute length is 3040 // already coded with an u4 in the classfile, but in practice, it's 3041 // unlikely to happen. 3042 assert((length+1) > length, "Overflow checking"); 3043 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 3044 for (int i = 0; i < length; i++) { 3045 sde[i] = array[i]; 3046 } 3047 sde[length] = '\0'; 3048 _source_debug_extension = sde; 3049 } 3050 } 3051 3052 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); } 3053 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); } 3054 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); } 3055 3056 const char* InstanceKlass::signature_name() const { 3057 3058 // Get the internal name as a c string 3059 const char* src = (const char*) (name()->as_C_string()); 3060 const int src_length = (int)strlen(src); 3061 3062 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 3063 3064 // Add L as type indicator 3065 int dest_index = 0; 3066 dest[dest_index++] = JVM_SIGNATURE_CLASS; 3067 3068 // Add the actual class name 3069 for (int src_index = 0; src_index < src_length; ) { 3070 dest[dest_index++] = src[src_index++]; 3071 } 3072 3073 if (is_hidden()) { // Replace the last '+' with a '.'. 3074 for (int index = (int)src_length; index > 0; index--) { 3075 if (dest[index] == '+') { 3076 dest[index] = JVM_SIGNATURE_DOT; 3077 break; 3078 } 3079 } 3080 } 3081 3082 // Add the semicolon and the null 3083 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 3084 dest[dest_index] = '\0'; 3085 return dest; 3086 } 3087 3088 ModuleEntry* InstanceKlass::module() const { 3089 if (is_hidden() && 3090 in_unnamed_package() && 3091 class_loader_data()->has_class_mirror_holder()) { 3092 // For a non-strong hidden class defined to an unnamed package, 3093 // its (class held) CLD will not have an unnamed module created for it. 3094 // Two choices to find the correct ModuleEntry: 3095 // 1. If hidden class is within a nest, use nest host's module 3096 // 2. Find the unnamed module off from the class loader 3097 // For now option #2 is used since a nest host is not set until 3098 // after the instance class is created in jvm_lookup_define_class(). 3099 if (class_loader_data()->is_boot_class_loader_data()) { 3100 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 3101 } else { 3102 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 3103 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 3104 return java_lang_Module::module_entry(module); 3105 } 3106 } 3107 3108 // Class is in a named package 3109 if (!in_unnamed_package()) { 3110 return _package_entry->module(); 3111 } 3112 3113 // Class is in an unnamed package, return its loader's unnamed module 3114 return class_loader_data()->unnamed_module(); 3115 } 3116 3117 bool InstanceKlass::in_javabase_module() const { 3118 return module()->name() == vmSymbols::java_base(); 3119 } 3120 3121 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 3122 3123 // ensure java/ packages only loaded by boot or platform builtin loaders 3124 // not needed for shared class since CDS does not archive prohibited classes. 3125 if (!in_aot_cache()) { 3126 check_prohibited_package(name(), loader_data, CHECK); 3127 } 3128 3129 if (in_aot_cache() && _package_entry != nullptr) { 3130 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) { 3131 // we can use the saved package 3132 assert(AOTMetaspace::in_aot_cache(_package_entry), "must be"); 3133 return; 3134 } else { 3135 _package_entry = nullptr; 3136 } 3137 } 3138 3139 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol 3140 // it returns, so we need to decrement it when the current function exits. 3141 TempNewSymbol from_class_name = 3142 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name()); 3143 3144 Symbol* pkg_name; 3145 if (pkg_entry != nullptr) { 3146 pkg_name = pkg_entry->name(); 3147 } else { 3148 pkg_name = from_class_name; 3149 } 3150 3151 if (pkg_name != nullptr && loader_data != nullptr) { 3152 3153 // Find in class loader's package entry table. 3154 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 3155 3156 // If the package name is not found in the loader's package 3157 // entry table, it is an indication that the package has not 3158 // been defined. Consider it defined within the unnamed module. 3159 if (_package_entry == nullptr) { 3160 3161 if (!ModuleEntryTable::javabase_defined()) { 3162 // Before java.base is defined during bootstrapping, define all packages in 3163 // the java.base module. If a non-java.base package is erroneously placed 3164 // in the java.base module it will be caught later when java.base 3165 // is defined by ModuleEntryTable::verify_javabase_packages check. 3166 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null"); 3167 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 3168 } else { 3169 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null"); 3170 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module()); 3171 } 3172 3173 // A package should have been successfully created 3174 DEBUG_ONLY(ResourceMark rm(THREAD)); 3175 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s", 3176 name()->as_C_string(), loader_data->loader_name_and_id()); 3177 } 3178 3179 if (log_is_enabled(Debug, module)) { 3180 ResourceMark rm(THREAD); 3181 ModuleEntry* m = _package_entry->module(); 3182 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 3183 external_name(), 3184 pkg_name->as_C_string(), 3185 loader_data->loader_name_and_id(), 3186 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 3187 } 3188 } else { 3189 ResourceMark rm(THREAD); 3190 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 3191 external_name(), 3192 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null", 3193 UNNAMED_MODULE); 3194 } 3195 } 3196 3197 // Function set_classpath_index ensures that for a non-null _package_entry 3198 // of the InstanceKlass, the entry is in the boot loader's package entry table. 3199 // It then sets the classpath_index in the package entry record. 3200 // 3201 // The classpath_index field is used to find the entry on the boot loader class 3202 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 3203 // in an unnamed module. It is also used to indicate (for all packages whose 3204 // classes are loaded by the boot loader) that at least one of the package's 3205 // classes has been loaded. 3206 void InstanceKlass::set_classpath_index(s2 path_index) { 3207 if (_package_entry != nullptr) { 3208 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 3209 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 3210 assert(path_index != -1, "Unexpected classpath_index"); 3211 _package_entry->set_classpath_index(path_index); 3212 } 3213 } 3214 3215 // different versions of is_same_class_package 3216 3217 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 3218 oop classloader1 = this->class_loader(); 3219 PackageEntry* classpkg1 = this->package(); 3220 if (class2->is_objArray_klass()) { 3221 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 3222 } 3223 3224 oop classloader2; 3225 PackageEntry* classpkg2; 3226 if (class2->is_instance_klass()) { 3227 classloader2 = class2->class_loader(); 3228 classpkg2 = class2->package(); 3229 } else { 3230 assert(class2->is_typeArray_klass(), "should be type array"); 3231 classloader2 = nullptr; 3232 classpkg2 = nullptr; 3233 } 3234 3235 // Same package is determined by comparing class loader 3236 // and package entries. Both must be the same. This rule 3237 // applies even to classes that are defined in the unnamed 3238 // package, they still must have the same class loader. 3239 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 3240 return true; 3241 } 3242 3243 return false; 3244 } 3245 3246 // return true if this class and other_class are in the same package. Classloader 3247 // and classname information is enough to determine a class's package 3248 bool InstanceKlass::is_same_class_package(oop other_class_loader, 3249 const Symbol* other_class_name) const { 3250 if (class_loader() != other_class_loader) { 3251 return false; 3252 } 3253 if (name()->fast_compare(other_class_name) == 0) { 3254 return true; 3255 } 3256 3257 { 3258 ResourceMark rm; 3259 3260 bool bad_class_name = false; 3261 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 3262 if (bad_class_name) { 3263 return false; 3264 } 3265 // Check that package_from_class_name() returns null, not "", if there is no package. 3266 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string"); 3267 3268 const Symbol* const this_package_name = 3269 this->package() != nullptr ? this->package()->name() : nullptr; 3270 3271 if (this_package_name == nullptr || other_pkg == nullptr) { 3272 // One of the two doesn't have a package. Only return true if the other 3273 // one also doesn't have a package. 3274 return this_package_name == other_pkg; 3275 } 3276 3277 // Check if package is identical 3278 return this_package_name->fast_compare(other_pkg) == 0; 3279 } 3280 } 3281 3282 static bool is_prohibited_package_slow(Symbol* class_name) { 3283 // Caller has ResourceMark 3284 int length; 3285 jchar* unicode = class_name->as_unicode(length); 3286 return (length >= 5 && 3287 unicode[0] == 'j' && 3288 unicode[1] == 'a' && 3289 unicode[2] == 'v' && 3290 unicode[3] == 'a' && 3291 unicode[4] == '/'); 3292 } 3293 3294 // Only boot and platform class loaders can define classes in "java/" packages. 3295 void InstanceKlass::check_prohibited_package(Symbol* class_name, 3296 ClassLoaderData* loader_data, 3297 TRAPS) { 3298 if (!loader_data->is_boot_class_loader_data() && 3299 !loader_data->is_platform_class_loader_data() && 3300 class_name != nullptr && class_name->utf8_length() >= 5) { 3301 ResourceMark rm(THREAD); 3302 bool prohibited; 3303 const u1* base = class_name->base(); 3304 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) { 3305 prohibited = is_prohibited_package_slow(class_name); 3306 } else { 3307 char* name = class_name->as_C_string(); 3308 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/'); 3309 } 3310 if (prohibited) { 3311 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 3312 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'"); 3313 char* name = pkg_name->as_C_string(); 3314 const char* class_loader_name = loader_data->loader_name_and_id(); 3315 StringUtils::replace_no_expand(name, "/", "."); 3316 const char* msg_text1 = "Class loader (instance of): "; 3317 const char* msg_text2 = " tried to load prohibited package name: "; 3318 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 3319 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 3320 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 3321 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 3322 } 3323 } 3324 return; 3325 } 3326 3327 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 3328 constantPoolHandle i_cp(THREAD, constants()); 3329 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 3330 int ioff = iter.inner_class_info_index(); 3331 if (ioff != 0) { 3332 // Check to see if the name matches the class we're looking for 3333 // before attempting to find the class. 3334 if (i_cp->klass_name_at_matches(this, ioff)) { 3335 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 3336 if (this == inner_klass) { 3337 *ooff = iter.outer_class_info_index(); 3338 *noff = iter.inner_name_index(); 3339 return true; 3340 } 3341 } 3342 } 3343 } 3344 return false; 3345 } 3346 3347 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 3348 InstanceKlass* outer_klass = nullptr; 3349 *inner_is_member = false; 3350 int ooff = 0, noff = 0; 3351 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 3352 if (has_inner_classes_attr) { 3353 constantPoolHandle i_cp(THREAD, constants()); 3354 if (ooff != 0) { 3355 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 3356 if (!ok->is_instance_klass()) { 3357 // If the outer class is not an instance klass then it cannot have 3358 // declared any inner classes. 3359 ResourceMark rm(THREAD); 3360 // Names are all known to be < 64k so we know this formatted message is not excessively large. 3361 Exceptions::fthrow( 3362 THREAD_AND_LOCATION, 3363 vmSymbols::java_lang_IncompatibleClassChangeError(), 3364 "%s and %s disagree on InnerClasses attribute", 3365 ok->external_name(), 3366 external_name()); 3367 return nullptr; 3368 } 3369 outer_klass = InstanceKlass::cast(ok); 3370 *inner_is_member = true; 3371 } 3372 if (nullptr == outer_klass) { 3373 // It may be a local class; try for that. 3374 int encl_method_class_idx = enclosing_method_class_index(); 3375 if (encl_method_class_idx != 0) { 3376 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 3377 outer_klass = InstanceKlass::cast(ok); 3378 *inner_is_member = false; 3379 } 3380 } 3381 } 3382 3383 // If no inner class attribute found for this class. 3384 if (nullptr == outer_klass) return nullptr; 3385 3386 // Throws an exception if outer klass has not declared k as an inner klass 3387 // We need evidence that each klass knows about the other, or else 3388 // the system could allow a spoof of an inner class to gain access rights. 3389 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 3390 return outer_klass; 3391 } 3392 3393 u2 InstanceKlass::compute_modifier_flags() const { 3394 u2 access = access_flags().as_unsigned_short(); 3395 3396 // But check if it happens to be member class. 3397 InnerClassesIterator iter(this); 3398 for (; !iter.done(); iter.next()) { 3399 int ioff = iter.inner_class_info_index(); 3400 // Inner class attribute can be zero, skip it. 3401 // Strange but true: JVM spec. allows null inner class refs. 3402 if (ioff == 0) continue; 3403 3404 // only look at classes that are already loaded 3405 // since we are looking for the flags for our self. 3406 Symbol* inner_name = constants()->klass_name_at(ioff); 3407 if (name() == inner_name) { 3408 // This is really a member class. 3409 access = iter.inner_access_flags(); 3410 break; 3411 } 3412 } 3413 // Remember to strip ACC_SUPER bit 3414 return (access & (~JVM_ACC_SUPER)); 3415 } 3416 3417 jint InstanceKlass::jvmti_class_status() const { 3418 jint result = 0; 3419 3420 if (is_linked()) { 3421 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3422 } 3423 3424 if (is_initialized()) { 3425 assert(is_linked(), "Class status is not consistent"); 3426 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3427 } 3428 if (is_in_error_state()) { 3429 result |= JVMTI_CLASS_STATUS_ERROR; 3430 } 3431 return result; 3432 } 3433 3434 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) { 3435 bool implements_interface; // initialized by method_at_itable_or_null 3436 Method* m = method_at_itable_or_null(holder, index, 3437 implements_interface); // out parameter 3438 if (m != nullptr) { 3439 assert(implements_interface, "sanity"); 3440 return m; 3441 } else if (implements_interface) { 3442 // Throw AbstractMethodError since corresponding itable slot is empty. 3443 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3444 } else { 3445 // If the interface isn't implemented by the receiver class, 3446 // the VM should throw IncompatibleClassChangeError. 3447 ResourceMark rm(THREAD); 3448 stringStream ss; 3449 bool same_module = (module() == holder->module()); 3450 ss.print("Receiver class %s does not implement " 3451 "the interface %s defining the method to be called " 3452 "(%s%s%s)", 3453 external_name(), holder->external_name(), 3454 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3455 (same_module) ? "" : "; ", 3456 (same_module) ? "" : holder->class_in_module_of_loader()); 3457 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3458 } 3459 } 3460 3461 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) { 3462 klassItable itable(this); 3463 for (int i = 0; i < itable.size_offset_table(); i++) { 3464 itableOffsetEntry* offset_entry = itable.offset_entry(i); 3465 if (offset_entry->interface_klass() == holder) { 3466 implements_interface = true; 3467 itableMethodEntry* ime = offset_entry->first_method_entry(this); 3468 Method* m = ime[index].method(); 3469 return m; 3470 } 3471 } 3472 implements_interface = false; 3473 return nullptr; // offset entry not found 3474 } 3475 3476 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) { 3477 assert(is_linked(), "required"); 3478 assert(intf_method->method_holder()->is_interface(), "not an interface method"); 3479 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented"); 3480 3481 int vtable_index = Method::invalid_vtable_index; 3482 Symbol* name = intf_method->name(); 3483 Symbol* signature = intf_method->signature(); 3484 3485 // First check in default method array 3486 if (!intf_method->is_abstract() && default_methods() != nullptr) { 3487 int index = find_method_index(default_methods(), 3488 name, signature, 3489 Klass::OverpassLookupMode::find, 3490 Klass::StaticLookupMode::find, 3491 Klass::PrivateLookupMode::find); 3492 if (index >= 0) { 3493 vtable_index = default_vtable_indices()->at(index); 3494 } 3495 } 3496 if (vtable_index == Method::invalid_vtable_index) { 3497 // get vtable_index for miranda methods 3498 klassVtable vt = vtable(); 3499 vtable_index = vt.index_of_miranda(name, signature); 3500 } 3501 return vtable_index; 3502 } 3503 3504 #if INCLUDE_JVMTI 3505 // update default_methods for redefineclasses for methods that are 3506 // not yet in the vtable due to concurrent subclass define and superinterface 3507 // redefinition 3508 // Note: those in the vtable, should have been updated via adjust_method_entries 3509 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3510 // search the default_methods for uses of either obsolete or EMCP methods 3511 if (default_methods() != nullptr) { 3512 for (int index = 0; index < default_methods()->length(); index ++) { 3513 Method* old_method = default_methods()->at(index); 3514 if (old_method == nullptr || !old_method->is_old()) { 3515 continue; // skip uninteresting entries 3516 } 3517 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3518 Method* new_method = old_method->get_new_method(); 3519 default_methods()->at_put(index, new_method); 3520 3521 if (log_is_enabled(Info, redefine, class, update)) { 3522 ResourceMark rm; 3523 if (!(*trace_name_printed)) { 3524 log_info(redefine, class, update) 3525 ("adjust: klassname=%s default methods from name=%s", 3526 external_name(), old_method->method_holder()->external_name()); 3527 *trace_name_printed = true; 3528 } 3529 log_debug(redefine, class, update, vtables) 3530 ("default method update: %s(%s) ", 3531 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3532 } 3533 } 3534 } 3535 } 3536 #endif // INCLUDE_JVMTI 3537 3538 // On-stack replacement stuff 3539 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3540 assert_lock_strong(NMethodState_lock); 3541 #ifndef PRODUCT 3542 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3543 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3544 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3545 #endif 3546 // only one compilation can be active 3547 assert(n->is_osr_method(), "wrong kind of nmethod"); 3548 n->set_osr_link(osr_nmethods_head()); 3549 set_osr_nmethods_head(n); 3550 // Raise the highest osr level if necessary 3551 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level())); 3552 3553 // Get rid of the osr methods for the same bci that have lower levels. 3554 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3555 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3556 if (inv != nullptr && inv->is_in_use()) { 3557 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL); 3558 } 3559 } 3560 } 3561 3562 // Remove osr nmethod from the list. Return true if found and removed. 3563 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3564 // This is a short non-blocking critical region, so the no safepoint check is ok. 3565 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3566 assert(n->is_osr_method(), "wrong kind of nmethod"); 3567 nmethod* last = nullptr; 3568 nmethod* cur = osr_nmethods_head(); 3569 int max_level = CompLevel_none; // Find the max comp level excluding n 3570 Method* m = n->method(); 3571 // Search for match 3572 bool found = false; 3573 while(cur != nullptr && cur != n) { 3574 if (m == cur->method()) { 3575 // Find max level before n 3576 max_level = MAX2(max_level, cur->comp_level()); 3577 } 3578 last = cur; 3579 cur = cur->osr_link(); 3580 } 3581 nmethod* next = nullptr; 3582 if (cur == n) { 3583 found = true; 3584 next = cur->osr_link(); 3585 if (last == nullptr) { 3586 // Remove first element 3587 set_osr_nmethods_head(next); 3588 } else { 3589 last->set_osr_link(next); 3590 } 3591 } 3592 n->set_osr_link(nullptr); 3593 cur = next; 3594 while (cur != nullptr) { 3595 // Find max level after n 3596 if (m == cur->method()) { 3597 max_level = MAX2(max_level, cur->comp_level()); 3598 } 3599 cur = cur->osr_link(); 3600 } 3601 m->set_highest_osr_comp_level(max_level); 3602 return found; 3603 } 3604 3605 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) { 3606 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3607 nmethod* osr = osr_nmethods_head(); 3608 int found = 0; 3609 while (osr != nullptr) { 3610 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3611 if (osr->method() == m) { 3612 deopt_scope->mark(osr); 3613 found++; 3614 } 3615 osr = osr->osr_link(); 3616 } 3617 return found; 3618 } 3619 3620 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3621 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3622 nmethod* osr = osr_nmethods_head(); 3623 nmethod* best = nullptr; 3624 while (osr != nullptr) { 3625 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3626 // There can be a time when a c1 osr method exists but we are waiting 3627 // for a c2 version. When c2 completes its osr nmethod we will trash 3628 // the c1 version and only be able to find the c2 version. However 3629 // while we overflow in the c1 code at back branches we don't want to 3630 // try and switch to the same code as we are already running 3631 3632 if (osr->method() == m && 3633 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3634 if (match_level) { 3635 if (osr->comp_level() == comp_level) { 3636 // Found a match - return it. 3637 return osr; 3638 } 3639 } else { 3640 if (best == nullptr || (osr->comp_level() > best->comp_level())) { 3641 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) { 3642 // Found the best possible - return it. 3643 return osr; 3644 } 3645 best = osr; 3646 } 3647 } 3648 } 3649 osr = osr->osr_link(); 3650 } 3651 3652 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set"); 3653 if (best != nullptr && best->comp_level() >= comp_level) { 3654 return best; 3655 } 3656 return nullptr; 3657 } 3658 3659 // ----------------------------------------------------------------------------------------------------- 3660 // Printing 3661 3662 #define BULLET " - " 3663 3664 static const char* state_names[] = { 3665 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3666 }; 3667 3668 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3669 for (int i = 0; i < len; i++) { 3670 intptr_t e = start[i]; 3671 st->print("%d : " INTPTR_FORMAT, i, e); 3672 if (MetaspaceObj::is_valid((Metadata*)e)) { 3673 st->print(" "); 3674 ((Metadata*)e)->print_value_on(st); 3675 } 3676 st->cr(); 3677 } 3678 } 3679 3680 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3681 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3682 } 3683 3684 const char* InstanceKlass::init_state_name() const { 3685 return state_names[init_state()]; 3686 } 3687 3688 void InstanceKlass::print_on(outputStream* st) const { 3689 assert(is_klass(), "must be klass"); 3690 Klass::print_on(st); 3691 3692 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3693 st->print(BULLET"klass size: %d", size()); st->cr(); 3694 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3695 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr(); 3696 st->print(BULLET"state: "); st->print_cr("%s", init_state_name()); 3697 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3698 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3699 st->print(BULLET"sub: "); 3700 Klass* sub = subklass(); 3701 int n; 3702 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) { 3703 if (n < MaxSubklassPrintSize) { 3704 sub->print_value_on(st); 3705 st->print(" "); 3706 } 3707 } 3708 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize); 3709 st->cr(); 3710 3711 if (is_interface()) { 3712 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3713 if (nof_implementors() == 1) { 3714 st->print_cr(BULLET"implementor: "); 3715 st->print(" "); 3716 implementor()->print_value_on(st); 3717 st->cr(); 3718 } 3719 } 3720 3721 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3722 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3723 if (Verbose || WizardMode) { 3724 Array<Method*>* method_array = methods(); 3725 for (int i = 0; i < method_array->length(); i++) { 3726 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3727 } 3728 } 3729 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3730 if (default_methods() != nullptr) { 3731 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3732 if (Verbose) { 3733 Array<Method*>* method_array = default_methods(); 3734 for (int i = 0; i < method_array->length(); i++) { 3735 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3736 } 3737 } 3738 } 3739 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices()); 3740 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3741 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3742 3743 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr(); 3744 3745 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr(); 3746 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr(); 3747 3748 if (secondary_supers() != nullptr) { 3749 if (Verbose) { 3750 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL); 3751 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length()); 3752 for (int i = 0; i < _secondary_supers->length(); i++) { 3753 ResourceMark rm; // for external_name() 3754 Klass* secondary_super = _secondary_supers->at(i); 3755 st->print(BULLET"%2d:", i); 3756 if (is_hashed) { 3757 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap); 3758 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK; 3759 st->print(" dist:%02d:", distance); 3760 } 3761 st->print_cr(" %p %s", secondary_super, secondary_super->external_name()); 3762 } 3763 } 3764 } 3765 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3766 3767 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data()); 3768 print_on_maybe_null(st, BULLET"source file: ", source_file_name()); 3769 if (source_debug_extension() != nullptr) { 3770 st->print(BULLET"source debug extension: "); 3771 st->print("%s", source_debug_extension()); 3772 st->cr(); 3773 } 3774 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations()); 3775 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations()); 3776 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations()); 3777 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations()); 3778 { 3779 bool have_pv = false; 3780 // previous versions are linked together through the InstanceKlass 3781 for (InstanceKlass* pv_node = previous_versions(); 3782 pv_node != nullptr; 3783 pv_node = pv_node->previous_versions()) { 3784 if (!have_pv) 3785 st->print(BULLET"previous version: "); 3786 have_pv = true; 3787 pv_node->constants()->print_value_on(st); 3788 } 3789 if (have_pv) st->cr(); 3790 } 3791 3792 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature()); 3793 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3794 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3795 print_on_maybe_null(st, BULLET"record components: ", record_components()); 3796 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr(); 3797 if (java_mirror() != nullptr) { 3798 st->print(BULLET"java mirror: "); 3799 java_mirror()->print_value_on(st); 3800 st->cr(); 3801 } else { 3802 st->print_cr(BULLET"java mirror: null"); 3803 } 3804 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3805 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3806 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3807 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3808 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3809 3810 FieldPrinter print_static_field(st); 3811 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3812 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3813 FieldPrinter print_nonstatic_field(st); 3814 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3815 ik->print_nonstatic_fields(&print_nonstatic_field); 3816 3817 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count()); 3818 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3819 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3820 while (map < end_map) { 3821 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3822 map++; 3823 } 3824 st->cr(); 3825 3826 if (fieldinfo_search_table() != nullptr) { 3827 st->print_cr(BULLET"---- field info search table:"); 3828 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table); 3829 } 3830 } 3831 3832 void InstanceKlass::print_value_on(outputStream* st) const { 3833 assert(is_klass(), "must be klass"); 3834 if (Verbose || WizardMode) access_flags().print_on(st); 3835 name()->print_value_on(st); 3836 } 3837 3838 void FieldPrinter::do_field(fieldDescriptor* fd) { 3839 _st->print(BULLET); 3840 if (_obj == nullptr) { 3841 fd->print_on(_st); 3842 _st->cr(); 3843 } else { 3844 fd->print_on_for(_st, _obj); 3845 _st->cr(); 3846 } 3847 } 3848 3849 3850 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3851 Klass::oop_print_on(obj, st); 3852 3853 if (this == vmClasses::String_klass()) { 3854 typeArrayOop value = java_lang_String::value(obj); 3855 juint length = java_lang_String::length(obj); 3856 if (value != nullptr && 3857 value->is_typeArray() && 3858 length <= (juint) value->length()) { 3859 st->print(BULLET"string: "); 3860 java_lang_String::print(obj, st); 3861 st->cr(); 3862 } 3863 } 3864 3865 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj)); 3866 FieldPrinter print_field(st, obj); 3867 print_nonstatic_fields(&print_field); 3868 3869 if (this == vmClasses::Class_klass()) { 3870 st->print(BULLET"signature: "); 3871 java_lang_Class::print_signature(obj, st); 3872 st->cr(); 3873 Klass* real_klass = java_lang_Class::as_Klass(obj); 3874 if (real_klass != nullptr && real_klass->is_instance_klass()) { 3875 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj)); 3876 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3877 } 3878 } else if (this == vmClasses::MethodType_klass()) { 3879 st->print(BULLET"signature: "); 3880 java_lang_invoke_MethodType::print_signature(obj, st); 3881 st->cr(); 3882 } 3883 } 3884 3885 #ifndef PRODUCT 3886 3887 bool InstanceKlass::verify_itable_index(int i) { 3888 int method_count = klassItable::method_count_for_interface(this); 3889 assert(i >= 0 && i < method_count, "index out of bounds"); 3890 return true; 3891 } 3892 3893 #endif //PRODUCT 3894 3895 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3896 st->print("a "); 3897 name()->print_value_on(st); 3898 obj->print_address_on(st); 3899 if (this == vmClasses::String_klass() 3900 && java_lang_String::value(obj) != nullptr) { 3901 ResourceMark rm; 3902 int len = java_lang_String::length(obj); 3903 int plen = (len < 24 ? len : 12); 3904 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3905 st->print(" = \"%s\"", str); 3906 if (len > plen) 3907 st->print("...[%d]", len); 3908 } else if (this == vmClasses::Class_klass()) { 3909 Klass* k = java_lang_Class::as_Klass(obj); 3910 st->print(" = "); 3911 if (k != nullptr) { 3912 k->print_value_on(st); 3913 } else { 3914 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3915 st->print("%s", tname ? tname : "type?"); 3916 } 3917 } else if (this == vmClasses::MethodType_klass()) { 3918 st->print(" = "); 3919 java_lang_invoke_MethodType::print_signature(obj, st); 3920 } else if (java_lang_boxing_object::is_instance(obj)) { 3921 st->print(" = "); 3922 java_lang_boxing_object::print(obj, st); 3923 } else if (this == vmClasses::LambdaForm_klass()) { 3924 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3925 if (vmentry != nullptr) { 3926 st->print(" => "); 3927 vmentry->print_value_on(st); 3928 } 3929 } else if (this == vmClasses::MemberName_klass()) { 3930 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3931 if (vmtarget != nullptr) { 3932 st->print(" = "); 3933 vmtarget->print_value_on(st); 3934 } else { 3935 oop clazz = java_lang_invoke_MemberName::clazz(obj); 3936 oop name = java_lang_invoke_MemberName::name(obj); 3937 if (clazz != nullptr) { 3938 clazz->print_value_on(st); 3939 } else { 3940 st->print("null"); 3941 } 3942 st->print("."); 3943 if (name != nullptr) { 3944 name->print_value_on(st); 3945 } else { 3946 st->print("null"); 3947 } 3948 } 3949 } 3950 } 3951 3952 const char* InstanceKlass::internal_name() const { 3953 return external_name(); 3954 } 3955 3956 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3957 const ModuleEntry* module_entry, 3958 const ClassFileStream* cfs) const { 3959 3960 if (ClassListWriter::is_enabled()) { 3961 ClassListWriter::write(this, cfs); 3962 } 3963 3964 print_class_load_helper(loader_data, module_entry, cfs); 3965 print_class_load_cause_logging(); 3966 } 3967 3968 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data, 3969 const ModuleEntry* module_entry, 3970 const ClassFileStream* cfs) const { 3971 3972 if (!log_is_enabled(Info, class, load)) { 3973 return; 3974 } 3975 3976 ResourceMark rm; 3977 LogMessage(class, load) msg; 3978 stringStream info_stream; 3979 3980 // Name and class hierarchy info 3981 info_stream.print("%s", external_name()); 3982 3983 // Source 3984 if (cfs != nullptr) { 3985 if (cfs->source() != nullptr) { 3986 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string(); 3987 if (module_name != nullptr) { 3988 // When the boot loader created the stream, it didn't know the module name 3989 // yet. Let's format it now. 3990 if (cfs->from_boot_loader_modules_image()) { 3991 info_stream.print(" source: jrt:/%s", module_name); 3992 } else { 3993 info_stream.print(" source: %s", cfs->source()); 3994 } 3995 } else { 3996 info_stream.print(" source: %s", cfs->source()); 3997 } 3998 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3999 Thread* current = Thread::current(); 4000 Klass* caller = current->is_Java_thread() ? 4001 JavaThread::cast(current)->security_get_caller_class(1): 4002 nullptr; 4003 // caller can be null, for example, during a JVMTI VM_Init hook 4004 if (caller != nullptr) { 4005 info_stream.print(" source: instance of %s", caller->external_name()); 4006 } else { 4007 // source is unknown 4008 } 4009 } else { 4010 oop class_loader = loader_data->class_loader(); 4011 info_stream.print(" source: %s", class_loader->klass()->external_name()); 4012 } 4013 } else { 4014 assert(this->in_aot_cache(), "must be"); 4015 if (AOTMetaspace::in_aot_cache_dynamic_region((void*)this)) { 4016 info_stream.print(" source: shared objects file (top)"); 4017 } else { 4018 info_stream.print(" source: shared objects file"); 4019 } 4020 } 4021 4022 msg.info("%s", info_stream.as_string()); 4023 4024 if (log_is_enabled(Debug, class, load)) { 4025 stringStream debug_stream; 4026 4027 // Class hierarchy info 4028 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT, 4029 p2i(this), p2i(super())); 4030 4031 // Interfaces 4032 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) { 4033 debug_stream.print(" interfaces:"); 4034 int length = local_interfaces()->length(); 4035 for (int i = 0; i < length; i++) { 4036 debug_stream.print(" " PTR_FORMAT, 4037 p2i(local_interfaces()->at(i))); 4038 } 4039 } 4040 4041 // Class loader 4042 debug_stream.print(" loader: ["); 4043 loader_data->print_value_on(&debug_stream); 4044 debug_stream.print("]"); 4045 4046 // Classfile checksum 4047 if (cfs) { 4048 debug_stream.print(" bytes: %d checksum: %08x", 4049 cfs->length(), 4050 ClassLoader::crc32(0, (const char*)cfs->buffer(), 4051 cfs->length())); 4052 } 4053 4054 msg.debug("%s", debug_stream.as_string()); 4055 } 4056 } 4057 4058 void InstanceKlass::print_class_load_cause_logging() const { 4059 bool log_cause_native = log_is_enabled(Info, class, load, cause, native); 4060 if (log_cause_native || log_is_enabled(Info, class, load, cause)) { 4061 JavaThread* current = JavaThread::current(); 4062 ResourceMark rm(current); 4063 const char* name = external_name(); 4064 4065 if (LogClassLoadingCauseFor == nullptr || 4066 (strcmp("*", LogClassLoadingCauseFor) != 0 && 4067 strstr(name, LogClassLoadingCauseFor) == nullptr)) { 4068 return; 4069 } 4070 4071 // Log Java stack first 4072 { 4073 LogMessage(class, load, cause) msg; 4074 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4075 4076 info_stream.print_cr("Java stack when loading %s:", name); 4077 current->print_stack_on(&info_stream); 4078 } 4079 4080 // Log native stack second 4081 if (log_cause_native) { 4082 // Log to string first so that lines can be indented 4083 stringStream stack_stream; 4084 char buf[O_BUFLEN]; 4085 address lastpc = nullptr; 4086 NativeStackPrinter nsp(current); 4087 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc, 4088 true /* print_source_info */, -1 /* max stack */); 4089 4090 LogMessage(class, load, cause, native) msg; 4091 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4092 info_stream.print_cr("Native stack when loading %s:", name); 4093 4094 // Print each native stack line to the log 4095 int size = (int) stack_stream.size(); 4096 char* stack = stack_stream.as_string(); 4097 char* stack_end = stack + size; 4098 char* line_start = stack; 4099 for (char* p = stack; p < stack_end; p++) { 4100 if (*p == '\n') { 4101 *p = '\0'; 4102 info_stream.print_cr("\t%s", line_start); 4103 line_start = p + 1; 4104 } 4105 } 4106 if (line_start < stack_end) { 4107 info_stream.print_cr("\t%s", line_start); 4108 } 4109 } 4110 } 4111 } 4112 4113 // Verification 4114 4115 class VerifyFieldClosure: public BasicOopIterateClosure { 4116 protected: 4117 template <class T> void do_oop_work(T* p) { 4118 oop obj = RawAccess<>::oop_load(p); 4119 if (!oopDesc::is_oop_or_null(obj)) { 4120 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 4121 Universe::print_on(tty); 4122 guarantee(false, "boom"); 4123 } 4124 } 4125 public: 4126 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 4127 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 4128 }; 4129 4130 void InstanceKlass::verify_on(outputStream* st) { 4131 #ifndef PRODUCT 4132 // Avoid redundant verifies, this really should be in product. 4133 if (_verify_count == Universe::verify_count()) return; 4134 _verify_count = Universe::verify_count(); 4135 #endif 4136 4137 // Verify Klass 4138 Klass::verify_on(st); 4139 4140 // Verify that klass is present in ClassLoaderData 4141 guarantee(class_loader_data()->contains_klass(this), 4142 "this class isn't found in class loader data"); 4143 4144 // Verify vtables 4145 if (is_linked()) { 4146 // $$$ This used to be done only for m/s collections. Doing it 4147 // always seemed a valid generalization. (DLD -- 6/00) 4148 vtable().verify(st); 4149 } 4150 4151 // Verify first subklass 4152 if (subklass() != nullptr) { 4153 guarantee(subklass()->is_klass(), "should be klass"); 4154 } 4155 4156 // Verify siblings 4157 Klass* super = this->super(); 4158 Klass* sib = next_sibling(); 4159 if (sib != nullptr) { 4160 if (sib == this) { 4161 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 4162 } 4163 4164 guarantee(sib->is_klass(), "should be klass"); 4165 guarantee(sib->super() == super, "siblings should have same superklass"); 4166 } 4167 4168 // Verify local interfaces 4169 if (local_interfaces()) { 4170 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 4171 for (int j = 0; j < local_interfaces->length(); j++) { 4172 InstanceKlass* e = local_interfaces->at(j); 4173 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 4174 } 4175 } 4176 4177 // Verify transitive interfaces 4178 if (transitive_interfaces() != nullptr) { 4179 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 4180 for (int j = 0; j < transitive_interfaces->length(); j++) { 4181 InstanceKlass* e = transitive_interfaces->at(j); 4182 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 4183 } 4184 } 4185 4186 // Verify methods 4187 if (methods() != nullptr) { 4188 Array<Method*>* methods = this->methods(); 4189 for (int j = 0; j < methods->length(); j++) { 4190 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4191 } 4192 for (int j = 0; j < methods->length() - 1; j++) { 4193 Method* m1 = methods->at(j); 4194 Method* m2 = methods->at(j + 1); 4195 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4196 } 4197 } 4198 4199 // Verify method ordering 4200 if (method_ordering() != nullptr) { 4201 Array<int>* method_ordering = this->method_ordering(); 4202 int length = method_ordering->length(); 4203 if (JvmtiExport::can_maintain_original_method_order() || 4204 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) { 4205 guarantee(length == methods()->length(), "invalid method ordering length"); 4206 jlong sum = 0; 4207 for (int j = 0; j < length; j++) { 4208 int original_index = method_ordering->at(j); 4209 guarantee(original_index >= 0, "invalid method ordering index"); 4210 guarantee(original_index < length, "invalid method ordering index"); 4211 sum += original_index; 4212 } 4213 // Verify sum of indices 0,1,...,length-1 4214 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 4215 } else { 4216 guarantee(length == 0, "invalid method ordering length"); 4217 } 4218 } 4219 4220 // Verify default methods 4221 if (default_methods() != nullptr) { 4222 Array<Method*>* methods = this->default_methods(); 4223 for (int j = 0; j < methods->length(); j++) { 4224 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4225 } 4226 for (int j = 0; j < methods->length() - 1; j++) { 4227 Method* m1 = methods->at(j); 4228 Method* m2 = methods->at(j + 1); 4229 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4230 } 4231 } 4232 4233 // Verify JNI static field identifiers 4234 if (jni_ids() != nullptr) { 4235 jni_ids()->verify(this); 4236 } 4237 4238 // Verify other fields 4239 if (constants() != nullptr) { 4240 guarantee(constants()->is_constantPool(), "should be constant pool"); 4241 } 4242 } 4243 4244 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 4245 Klass::oop_verify_on(obj, st); 4246 VerifyFieldClosure blk; 4247 obj->oop_iterate(&blk); 4248 } 4249 4250 // JNIid class for jfieldIDs only 4251 // Note to reviewers: 4252 // These JNI functions are just moved over to column 1 and not changed 4253 // in the compressed oops workspace. 4254 JNIid::JNIid(InstanceKlass* holder, int offset, JNIid* next) { 4255 _holder = holder; 4256 _offset = offset; 4257 _next = next; 4258 DEBUG_ONLY(_is_static_field_id = false;) 4259 } 4260 4261 JNIid* JNIid::find(int offset) { 4262 JNIid* current = this; 4263 while (current != nullptr) { 4264 if (current->offset() == offset) return current; 4265 current = current->next(); 4266 } 4267 return nullptr; 4268 } 4269 4270 void JNIid::deallocate(JNIid* current) { 4271 while (current != nullptr) { 4272 JNIid* next = current->next(); 4273 delete current; 4274 current = next; 4275 } 4276 } 4277 4278 void JNIid::verify(InstanceKlass* holder) { 4279 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 4280 int end_field_offset; 4281 end_field_offset = first_field_offset + (holder->static_field_size() * wordSize); 4282 4283 JNIid* current = this; 4284 while (current != nullptr) { 4285 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 4286 #ifdef ASSERT 4287 int o = current->offset(); 4288 if (current->is_static_field_id()) { 4289 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 4290 } 4291 #endif 4292 current = current->next(); 4293 } 4294 } 4295 4296 void InstanceKlass::set_init_state(ClassState state) { 4297 #ifdef ASSERT 4298 bool good_state = in_aot_cache() ? (_init_state <= state) 4299 : (_init_state < state); 4300 assert(good_state || state == allocated, "illegal state transition"); 4301 #endif 4302 assert(_init_thread == nullptr, "should be cleared before state change"); 4303 AtomicAccess::release_store(&_init_state, state); 4304 } 4305 4306 #if INCLUDE_JVMTI 4307 4308 // RedefineClasses() support for previous versions 4309 4310 // Globally, there is at least one previous version of a class to walk 4311 // during class unloading, which is saved because old methods in the class 4312 // are still running. Otherwise the previous version list is cleaned up. 4313 bool InstanceKlass::_should_clean_previous_versions = false; 4314 4315 // Returns true if there are previous versions of a class for class 4316 // unloading only. Also resets the flag to false. purge_previous_version 4317 // will set the flag to true if there are any left, i.e., if there's any 4318 // work to do for next time. This is to avoid the expensive code cache 4319 // walk in CLDG::clean_deallocate_lists(). 4320 bool InstanceKlass::should_clean_previous_versions_and_reset() { 4321 bool ret = _should_clean_previous_versions; 4322 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s", 4323 ret ? "true" : "false"); 4324 _should_clean_previous_versions = false; 4325 return ret; 4326 } 4327 4328 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'. 4329 // These obsolete methods only exist in the previous version and we're about to delete the memory for them. 4330 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table. 4331 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) { 4332 Array<Method*>* method_refs = klass->methods(); 4333 for (int k = 0; k < method_refs->length(); k++) { 4334 Method* method = method_refs->at(k); 4335 // Only need to clear obsolete methods. 4336 if (method != nullptr && method->is_obsolete()) { 4337 method->clear_jmethod_id(); 4338 } 4339 } 4340 } 4341 4342 // Purge previous versions before adding new previous versions of the class and 4343 // during class unloading. 4344 void InstanceKlass::purge_previous_version_list() { 4345 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 4346 assert(has_been_redefined(), "Should only be called for main class"); 4347 4348 // Quick exit. 4349 if (previous_versions() == nullptr) { 4350 return; 4351 } 4352 4353 // This klass has previous versions so see what we can cleanup 4354 // while it is safe to do so. 4355 4356 int deleted_count = 0; // leave debugging breadcrumbs 4357 int live_count = 0; 4358 ClassLoaderData* loader_data = class_loader_data(); 4359 assert(loader_data != nullptr, "should never be null"); 4360 4361 ResourceMark rm; 4362 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 4363 4364 // previous versions are linked together through the InstanceKlass 4365 InstanceKlass* pv_node = previous_versions(); 4366 InstanceKlass* last = this; 4367 int version = 0; 4368 4369 // check the previous versions list 4370 for (; pv_node != nullptr; ) { 4371 4372 ConstantPool* pvcp = pv_node->constants(); 4373 assert(pvcp != nullptr, "cp ref was unexpectedly cleared"); 4374 4375 if (!pvcp->on_stack()) { 4376 // If the constant pool isn't on stack, none of the methods 4377 // are executing. Unlink this previous_version. 4378 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 4379 // so will be deallocated during the next phase of class unloading. 4380 log_trace(redefine, class, iklass, purge) 4381 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node)); 4382 // Unlink from previous version list. 4383 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 4384 InstanceKlass* next = pv_node->previous_versions(); 4385 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class 4386 pv_node->link_previous_versions(nullptr); // point next to null 4387 last->link_previous_versions(next); 4388 // Delete this node directly. Nothing is referring to it and we don't 4389 // want it to increase the counter for metadata to delete in CLDG. 4390 MetadataFactory::free_metadata(loader_data, pv_node); 4391 pv_node = next; 4392 deleted_count++; 4393 version++; 4394 continue; 4395 } else { 4396 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder"); 4397 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 4398 live_count++; 4399 if (pvcp->in_aot_cache()) { 4400 // Shared previous versions can never be removed so no cleaning is needed. 4401 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node)); 4402 } else { 4403 // Previous version alive, set that clean is needed for next time. 4404 _should_clean_previous_versions = true; 4405 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node)); 4406 } 4407 } 4408 4409 // next previous version 4410 last = pv_node; 4411 pv_node = pv_node->previous_versions(); 4412 version++; 4413 } 4414 log_trace(redefine, class, iklass, purge) 4415 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 4416 } 4417 4418 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 4419 int emcp_method_count) { 4420 int obsolete_method_count = old_methods->length() - emcp_method_count; 4421 4422 if (emcp_method_count != 0 && obsolete_method_count != 0 && 4423 _previous_versions != nullptr) { 4424 // We have a mix of obsolete and EMCP methods so we have to 4425 // clear out any matching EMCP method entries the hard way. 4426 int local_count = 0; 4427 for (int i = 0; i < old_methods->length(); i++) { 4428 Method* old_method = old_methods->at(i); 4429 if (old_method->is_obsolete()) { 4430 // only obsolete methods are interesting 4431 Symbol* m_name = old_method->name(); 4432 Symbol* m_signature = old_method->signature(); 4433 4434 // previous versions are linked together through the InstanceKlass 4435 int j = 0; 4436 for (InstanceKlass* prev_version = _previous_versions; 4437 prev_version != nullptr; 4438 prev_version = prev_version->previous_versions(), j++) { 4439 4440 Array<Method*>* method_refs = prev_version->methods(); 4441 for (int k = 0; k < method_refs->length(); k++) { 4442 Method* method = method_refs->at(k); 4443 4444 if (!method->is_obsolete() && 4445 method->name() == m_name && 4446 method->signature() == m_signature) { 4447 // The current RedefineClasses() call has made all EMCP 4448 // versions of this method obsolete so mark it as obsolete 4449 log_trace(redefine, class, iklass, add) 4450 ("%s(%s): flush obsolete method @%d in version @%d", 4451 m_name->as_C_string(), m_signature->as_C_string(), k, j); 4452 4453 method->set_is_obsolete(); 4454 break; 4455 } 4456 } 4457 4458 // The previous loop may not find a matching EMCP method, but 4459 // that doesn't mean that we can optimize and not go any 4460 // further back in the PreviousVersion generations. The EMCP 4461 // method for this generation could have already been made obsolete, 4462 // but there still may be an older EMCP method that has not 4463 // been made obsolete. 4464 } 4465 4466 if (++local_count >= obsolete_method_count) { 4467 // no more obsolete methods so bail out now 4468 break; 4469 } 4470 } 4471 } 4472 } 4473 } 4474 4475 // Save the scratch_class as the previous version if any of the methods are running. 4476 // The previous_versions are used to set breakpoints in EMCP methods and they are 4477 // also used to clean MethodData links to redefined methods that are no longer running. 4478 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 4479 int emcp_method_count) { 4480 assert(Thread::current()->is_VM_thread(), 4481 "only VMThread can add previous versions"); 4482 4483 ResourceMark rm; 4484 log_trace(redefine, class, iklass, add) 4485 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 4486 4487 // Clean out old previous versions for this class 4488 purge_previous_version_list(); 4489 4490 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 4491 // a previous redefinition may be made obsolete by this redefinition. 4492 Array<Method*>* old_methods = scratch_class->methods(); 4493 mark_newly_obsolete_methods(old_methods, emcp_method_count); 4494 4495 // If the constant pool for this previous version of the class 4496 // is not marked as being on the stack, then none of the methods 4497 // in this previous version of the class are on the stack so 4498 // we don't need to add this as a previous version. 4499 ConstantPool* cp_ref = scratch_class->constants(); 4500 if (!cp_ref->on_stack()) { 4501 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 4502 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 4503 return; 4504 } 4505 4506 // Add previous version if any methods are still running or if this is 4507 // a shared class which should never be removed. 4508 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version"); 4509 scratch_class->link_previous_versions(previous_versions()); 4510 link_previous_versions(scratch_class); 4511 if (cp_ref->in_aot_cache()) { 4512 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared"); 4513 } else { 4514 // We only set clean_previous_versions flag for processing during class 4515 // unloading for non-shared classes. 4516 _should_clean_previous_versions = true; 4517 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4518 } 4519 } // end add_previous_version() 4520 4521 #endif // INCLUDE_JVMTI 4522 4523 Method* InstanceKlass::method_with_idnum(int idnum) const { 4524 Method* m = nullptr; 4525 if (idnum < methods()->length()) { 4526 m = methods()->at(idnum); 4527 } 4528 if (m == nullptr || m->method_idnum() != idnum) { 4529 for (int index = 0; index < methods()->length(); ++index) { 4530 m = methods()->at(index); 4531 if (m->method_idnum() == idnum) { 4532 return m; 4533 } 4534 } 4535 // None found, return null for the caller to handle. 4536 return nullptr; 4537 } 4538 return m; 4539 } 4540 4541 4542 Method* InstanceKlass::method_with_orig_idnum(int idnum) const { 4543 if (idnum >= methods()->length()) { 4544 return nullptr; 4545 } 4546 Method* m = methods()->at(idnum); 4547 if (m != nullptr && m->orig_method_idnum() == idnum) { 4548 return m; 4549 } 4550 // Obsolete method idnum does not match the original idnum 4551 for (int index = 0; index < methods()->length(); ++index) { 4552 m = methods()->at(index); 4553 if (m->orig_method_idnum() == idnum) { 4554 return m; 4555 } 4556 } 4557 // None found, return null for the caller to handle. 4558 return nullptr; 4559 } 4560 4561 4562 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const { 4563 const InstanceKlass* holder = get_klass_version(version); 4564 if (holder == nullptr) { 4565 return nullptr; // The version of klass is gone, no method is found 4566 } 4567 return holder->method_with_orig_idnum(idnum); 4568 } 4569 4570 #if INCLUDE_JVMTI 4571 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4572 return _cached_class_file; 4573 } 4574 4575 jint InstanceKlass::get_cached_class_file_len() { 4576 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4577 } 4578 4579 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4580 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4581 } 4582 #endif 4583 4584 // Make a step iterating over the class hierarchy under the root class. 4585 // Skips subclasses if requested. 4586 void ClassHierarchyIterator::next() { 4587 assert(_current != nullptr, "required"); 4588 if (_visit_subclasses && _current->subklass() != nullptr) { 4589 _current = _current->subklass(); 4590 return; // visit next subclass 4591 } 4592 _visit_subclasses = true; // reset 4593 while (_current->next_sibling() == nullptr && _current != _root) { 4594 _current = _current->java_super(); // backtrack; no more sibling subclasses left 4595 } 4596 if (_current == _root) { 4597 // Iteration is over (back at root after backtracking). Invalidate the iterator. 4598 _current = nullptr; 4599 return; 4600 } 4601 _current = _current->next_sibling(); 4602 return; // visit next sibling subclass 4603 } --- EOF ---