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